<RECORD 1>

Accession number:20145100353427
Title:Effect of HZSM-5 catalyst with different Si/Al ratios on characterization of pyrolysis bio-oil
Authors:Li, Pan (1); Wang, Xianhua (1); Shao, Jing'ai (1); Yang, Haiping (1); Chen, Hanping (1)
Author affiliation:(1) State Key Laboratory of Coal Combustion Huazhong University of Science and Technology, Wuhan , China
Corresponding author:Shao, Jing'ai
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:252-258
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to investigate the effect on biomass liquefaction of HZSM-5 zeolite under different silica to alumina ratio and adding amounts. The HZSM-5 (hydrogen zeolite) catalysts obtained by ion-exchange method were characterized using laser particle size analyzer, specific surface area and pore size analyzer with Brunauer-Emmett-Teller (BET) method and X-ray diffraction (XRD), and applied for the catalytic pyrolysis of wood at the optimum temperature of best oil yield. The bio-oils obtained from direct liquefaction with and without catalysts were characterized by GC-MS (Gas Chromatograph-Mass Spectrometer) analyses. The results indicated that: Compared with ZSM-5 zeolite, the crystal grain size of HZSM-5 zeolite prepared through ion exchange increased, and the particle size distribution was more concentrated, andthe catalyst had a preferable crystalline tacticity and a increased crystallinity, meanwhile, the surface area and the pore volume of HZSM-5 catalyst decreased, while pore size did not change significantly. When the HZSM-5 zeolite of different silica to alumina ratio were applied to pyrolysis, the yield of bio-oil decreased significantly (the maximum was up to 8%), the moisture content of the bio-oil increased. However, the composition of bio-oil and the relative content of the product changed a lot, it indicated that there was obvious catalytic effects during the direct liquefaction of biomass under HZSM-5 zeolite. Compared with non-catalyst pyrolysis, the contents of aldehydes, esters, ketones, furans and acid (oxygenated compounds) were reduced. It showed that HZSM-5 zeolite promoted a series of decarboxylation, decarbonylation reaction during the pyrolysis process, resulted to the reduction of the oxygen content of bio-oil and helped to improve the stability of bio-oil. With the increasing of silica to alumina ratio, the catalytic activity weakened a little. When the adding amounts of HZSM-5 zeolite were increased, a small variation of the yield of bio-oil occured, the moisture content of the bio-oil continued to go up, while the content of oxygen-containing compounds and acid aldehydes, esters, ketones, furans further reduced, promoting the formation of hydrocarbons, phenols, alcohols, the maximum percentage of the peak area could be up to 12.57% and 39.36%. Because HZSM-5 zeolite help to provide rich aperture on the surface, which was conducive to the formation of positive carbon ions, then the products of the first thermal decomposition carried on isomerization, cracking formation to convert as small molecules alkanes and alkenes, then go through polymerization reaction, cyclization reaction and a series of reactions to generate aromatic substances and so on. Owing to the above reaction procedure, there was a greater overall increasing in hydrocarbon substances. After the addition ratio was greater than 10%, the changing rate of various components decreased. Comprehensive analysis results of the type and amount of added catalyst showed that HZSM-5 (25) zeolite with the addition ratio of 10% played a more significant role on the catalytic liquefaction control of wood dust.
Number of references:25
Main heading:Catalyst activity
Controlled terms:Aldehydes - Alumina - Aromatic compounds - Biofuels - Biomass - Carboxylation - Catalysts - Cyclization - Esterification - Esters  - Gas oils - Grain size and shape - Hydrocarbons - Ion exchange - Ions - Ketones - Liquefaction - Moisture - Moisture determination - Oil shale  - Organic pollutants - Oxygen - Particle size - Particle size analysis - Pore size - Pyrolysis - Silica - X ray diffraction
Uncontrolled terms:Brunauer-Emmett-Teller method - Catalytic liquefaction - Comprehensive analysis - Different Si/Al ratio - Laser particle size analyzer - Oxygen-containing compounds - Polymerization reaction - Product property
Classification code:512.1 Petroleum Deposits - 523 Liquid Fuels - 525.1 Energy Resources and Renewable Energy Issues - 801 Chemistry - 801.4 Physical Chemistry - 802.2 Chemical Reactions - 802.3 Chemical Operations - 804 Chemical Products Generally - 812 Ceramics, Refractories and Glass - 812.1 Ceramics - 931.3 Atomic and Molecular Physics - 943.2 Mechanical Variables Measurements - 944.2 Moisture Measurements - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.20.031
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 2>

Accession number:20145100353421
Title:Peak-fitting based prediction of soil temperature according to soil moisture content in solar greenhouse
Authors:Ta, Na (1); Wu, Shiliu (1); Ma, Wenjuan (1); Chen, Bin (1); Zhu, Yingkai (1)
Author affiliation:(1) College of Electromechanical Engineering, Inner Mongolia Agricultural University, Hohhot, China
Corresponding author:Ta, Na
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:204-210
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil temperature and moisture directly impact on the root growth and seed germination of crops in greenhouse in cold area. Decreasing of soil moisture content would be beneficial for increasing soil temperature in greenhouse during cold situations. Considering low soil temperature that restricts activities of microorganisms in soil, optimizing of soil moisture content is essential to keep balance between soil temperature and activity of soil microorganisms. The objective of this research was to determine the authentic relationship between soil temperature and moisture content in greenhouse by establishing and validating of a soil temperature variation with soil moisture content equation using peak fitting analysis. All the works were carried out in a typical solar greenhouse from Dec 20, 2013 to Feb 20, 2014. We designed four test zones (2 m&times;2 m each) in the central part of the greenhouse, namely zone I (irrigated 10 h ago), zone II (irrigated 8 d ago), zone III (irrigated 33 d ago), and zone IV (control). To monitor the soil temperature, three soil moisture/temperature sensors were placed in soil of each test zone with 0, 15 and 30cm depth, respectively. For control zone, a soil moisture/temperature sensor was placed on the soil surface (0 cm). We tested the moisture content and temperature variations of different soil depth. According to a Single Peak Fitting Module (PEM), we obtained the Extreme Fitting Function of the diurnal change of soil temperature. The relationship between temperature-variation equation and the moisture content was determined by calculating the area under temperature-variation curve and analyzing coefficients of the equation. The extreme function which has specific physical meaning of parameters was named as Estimated Extreme function. The reliability and validity of Peak Fitting Method were confirmed by error analysis of certain moisture content in different weather condition on the surface of the control plot. We investigated the change of soil temperature under different moisture content in greenhouse by using Peak Fitting Method. The results showed that the condition of strong evaporation can increase soil temperature and resulted in enhancing of unsaturated hydraulic conductivity of soil and the suction on wet evaporate face, leading to increase of liquid water level to the dry-wet surface. Using this method to simulate the temperature variation curve, the minimum matching degree was 0.9590. Based on the calculation of enveloping area of temperature curve, we obtained the average soil temperature and found out that decrease of soil moisture content caused an increase of average temperature of soil in both day and night. According to the coefficients of fitting equation established by the data from sunny day, we found that amplitude, center and width factors decreased while offset substantially increased along with the decrease of soil moisture content on the soil surface. However, offset, center and width factors increased while amplitude decreased in soil at 15 cm depth, and all four factors increased in the soil at 30 cm depth when the soil moisture content decreased. These results indicated that drop of soil moisture content can result in decrease of the regenerative capacity of soil and content of liquid water, and down shift of dry-wet surface. Validation results showed that the minimal discrepancy of temperature was 0.71, implying that the four factors of Estimated Extreme function were good enough to calculate the change of soil temperature. The method developed in this work is able to improve the efficiency by decreasing the measurement of soil temperature and convert the discrete data points into a continuous function.
Number of references:18
Main heading:Soil surveys
Controlled terms:Data handling - Error analysis - Greenhouses - Liquids - Microorganisms - Moisture - Moisture control - Moisture determination - Reliability analysis - Seed  - Soil moisture - Soils - Solar heating - Temperature distribution - Water levels
Uncontrolled terms:Different moisture contents - Discrete data points - Regenerative capacity - Reliability and validity - Soil temperature variations - Temperature peaks - Temperature variation - Unsaturated hydraulic conductivity
Classification code:461.9 Biology - 483.1 Soils and Soil Mechanics - 614.2 Steam Power Plant Equipment and Operation - 641.1 Thermodynamics - 643.1 Space Heating - 723.2 Data Processing and Image Processing - 801.4 Physical Chemistry - 821.4 Agricultural Products - 821.6 Farm Buildings and Other Structures - 913 Production Planning and Control; Manufacturing - 921.6 Numerical Methods - 931.2 Physical Properties of Gases, Liquids and Solids - 944.2 Moisture Measurements
DOI:10.3969/j.issn.1002-6819.2014.20.025
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 3>

Accession number:20145100353406
Title:Simulation of water-salt transport by SWAP model under deficit irrigation with saline water
Authors:Yuan, Chengfu (1); Feng, Shaoyuan (1); Jiang, Jing (2); Huo, Zailin (3); Ji, Quanyi (1); Qi, Yanbing (3)
Author affiliation:(1) College of Hydraulic, Energy and Power Engineering, Yangzhou University, Yangzhou, China; (2) College of Water Resources Science and Engineering, Taiyuan University of Technology, Taiyuan, China; (3) Centre for Agricultural Water Research in China, China Agricultural University, Beijing, China
Corresponding author:Feng, Shaoyuan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:72-82
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The Shiyang River Basin is an interior river basin that faces excessive water explore and utilization, outstanding contradiction between water demand and water resources and environmental deterioration in arid Northwest China. The groundwater is an important resource for social and economic development, maintaining the ecological environment and agricultural irrigation. Due to excessive exploration, the groundwater salinity increases year by year. In order to make up the shortage of fresh water resources and ensure the steady development of agriculture in arid district, saline water and deficit irrigation has been widely used in agricultural production. In order to understand the soil water and salt transport under the condition of deficit irrigation with saline water, the agro-hydrological Soil-Water-Atmosphere-Plant (SWAP) model was calibrated and validated to simulate water-salt transport and grain yield of maize based on the field experiments and observed data in in 2013. At the same time, the soil water flux and salt flux were simulated by SWAP model under the condition of deficit irrigation with saline water. The results showed that SWAP model better reflected the change tendency of the measured values at the process of soil water calibration and validation. The RMSE values of every soil profile were less than 0.04 cm³/cm³ and the MRE values were less than 10%. Therefore, the calibrated and validated SWAP model described water transport effectively. At the process of soil salt calibration and validation, the simulation values reflected the change tendency of the measured values perfectly. The RMSE values at variable dates were less than 2.0 mg/cm² and the MRE values were less than 23%. Therefore, the calibrated and validated SWAP model reflected the effect on soil salt distribution by different irrigation conditions under the deficit irrigation with saline water effectively. At the process of grain maize yield calibration and validation, the simulation yield reflected the change tendency of the measured yield. Therefore, the calibrated and validated SWAP model reflected grain yield of maize under the deficit irrigation with saline water effectively. The simulation result of soil water flux showed that at the seedling stage of maize, the soil water flux above 40 cm was mainly upward and the flux mainly downward at the irrigation and rainfall stage. As the result of soil water flux of 60 cm under the deficit irrigation, it produced the deep leakage under the experimental conditions. The simulation result of soil salinity flux showed that it was similar between the soil water and soil salt transport. In seedling stage of maize, the soil salinity flux above 40 cm soil layer was given priority to upward because of the soil evaporation. In the stage of rainfall and irrigation, the soil salinity flux in all soil profile was mainly downward. The result of soil salinity flux at 60 cm showed that the salt brought by saline water irrigation could migrate to deep soil with the rain and leaching and it did not produce salt accumulation at the surface soil. The research results of this paper can provide valuable information for formulating deficit irrigation schedule with saline water.
Number of references:33
Main heading:Saline water
Controlled terms:Calibration - Computer simulation - Grain (agricultural product) - Groundwater - Groundwater resources - Irrigation - Plants (botany) - Rain - Salts - Soil moisture  - Soil surveys - Water management - Watersheds
Uncontrolled terms:Agricultural productions - Calibration and validations - Environmental deterioration - Saline water irrigations - Social and economic development - Soil salinity - Soil water fluxes - SWAP model
Classification code:443.3 Precipitation - 444 Water Resources - 461.9 Biology - 483.1 Soils and Soil Mechanics - 723.5 Computer Applications - 804.1 Organic Compounds - 821.3 Agricultural Methods - 821.4 Agricultural Products - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.20.010
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 4>

Accession number:20145100353432
Title:Analysis on changes of land use inputs and their willingness of land use for farmers
Authors:Liu, Chengwu (1); Huang, Limin (1)
Author affiliation:(1) School of Public Management, South-Central University for Nationalities, Wuhan, China
Corresponding author:Huang, Limin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:297-305
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Understanding the variation characteristics of farmers' behavior in land use investment and comprehending the current farmers' willingness of land use and food production are very useful and necessary for the formulation of relevant policies to ensure the security of China's food. With a stratified random sample method, 23 villages of 4 counties, 1 city and 1 region in Xianning city were surveyed and 1252 farmers' behavior data in land use was collected. From the perspective of the main factors of food production such as labor forces, land resources, agricultural machinery, fertilizers and pesticides, the farmers' behavior changes in land use investment from 1981 to 2011 and their current willingness of food production were analyzed in this paper. The results showed: 1) In aspect of labor investment, rural labors substantially shift to non-agricultural areas outside the region, the current main agricultural labors were characterized by female, middle-aged and low educational degree labor force. The labor investment per unit of land area reduced two-thirds significantly from 1981 to 2011. 2) In aspect of land resources input, because of the influence of land circulation, the actual operation of farm household farming land scale had significantly increased trend. However, farmers had not enlarged the main food crops' area. The double cropping paddy such as early paddy and late paddy transferred to middle-season paddy as well as paddy field shifted to dry land. As a result, the area of three kind food crops had shrunk by one seventh during the past 30 years. 3) As for the other factors of production inputs, farmyard manures were reduced, NPK chemical fertilizers were gradually replaced by compound fertilizers. The consumption of pesticides increased quickly. More and more families used agricultural machinery service in cultivation; the level of agricultural mechanization was improved significantly. 4) Agricultural technological progress and economic reason are two most important driving factors to effect farmers' behavior change in land use, the preferential agricultural policies such as "three make up one free" had limited impact on farmers' investment behavior. 5) The target of farmers' land use was divided into differentiation. The two thirds farmers just produce grain for his family, to some extent, it may will affect the safety of the food market. There farmers producing grain for market will become more and more important to regional food safety. The traditional model of "every family producing food" was replaced by the new model of "more specialized and large-scale peasant household production". Government land and agricultural policies, such as land consolidation and preferential agricultural policy, should focus on these farmers and support large-scale professional management farmers, and encourage small farmers out of agriculture to non-agricultural industries. 6) How to effectively stabilize the production area of main food crops is a severe problem. It needs more positive strategies to guide regulation of farmer's behavior in land use. With the conversion of marginal cultivated land to ecological land, the ecological land increased and the rural region has a precious opportunity to improve the ecosystem quality and enhance regional ecosystem services.
Number of references:20
Main heading:Land use
Controlled terms:Agricultural machinery - Chemical contamination - Commerce - Crops - Cultivation - Economics - Ecosystems - Fertilizers - Grain (agricultural product) - Investments  - Natural resources - Pesticides - Rural areas
Uncontrolled terms:Agricultural industries - Agricultural mechanization - Food production - Household behavior - Professional management - Stratified random sample - Technological progress - Variation characteristics
Classification code:403 Urban and Regional Planning and Development - 444 Water Resources - 454.3 Ecology and Ecosystems - 501 Exploration and Prospecting - 512 Petroleum and Related Deposits - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 822.3 Food Products - 911.2 Industrial Economics
DOI:10.3969/j.issn.1002-6819.2014.20.036
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 5>

Accession number:20145100353397
Title:Design and experiment of corn stripping monomer mechanism
Authors:Zhang, Zhilong (1); Zhang, Dongxing (1); Cui, Tao (1); Yang, Li (1); Li, Kehong (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing, China
Corresponding author:Zhang, Dongxing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:1-9
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Aiming at the row width of corn head was fixed and could not be adjusted by the corn row spacing. The corn stripping monomer mechanism was designed. The mechanism mainly consisted of a stripping roller, a stripping bar, a stripping bar mounting seat, and a transmission axis etc. The space between the adjacent stripping bars was less than the diameter of the ear big end and bigger than the diameter of the corn stalks. The machine moved forward while the stripping roller rotated. When the stripping bars touched the big end of the ear, the ear was picked off from the plant by the force of the impact. The space between the stripping bars, the rows of the stripping bars, the diameter of the stripping mechanism, and the height from the axis to the ear big end were determined. Mechanical analysis was done to explore the best space between the stripping bars. Theoretical calculation was conducted to obtain the best rows, the diameter of the stripping mechanism, and the height. After the ear was picked off from the plant, the ear was thrown backwards and collected. The shape of stripping bars was important to reducing the ear loss rate. In order to obtain the best diameter of the stripping bars, the motion analysis was done in the corn picking-off process. If the ear was thrown backwards, the coordinate of the ear should be less than the coordinate of the stripping bar's outer edge point. The diameter of the stripping bar was determined by the calculation. The preliminary results showed that the corn stripping mechanism could reliably finish the ear picking-off process. The plants were installed on the walking trolley by the fixture and fed into the corn stripping mechanism. Single factor tests of rotational speed were done. The tests took the grain broken rate, grain loss rate, and ear loss rate as index. The tests were done when the grain moisture content was 35.5%. The single factor test of rotational speed was done in five levels such as 80, 110, 140, 170, and 200 r/min. The corn stripping mechanism worked well when the rotational speed was 110-170 r/min. The grain broken rate was 0.08%-0.48%, and the grain loss rate was 0.03%-0.17%. It was comprehensively considered that the best speed range was 110-170 r/min. The orthogonal test was done to explore the best working conditions in the field. Three factors were considered in the orthogonal test including rotational speed, bars shape, and the distance from the axis to the ear. The rotational speed selected three levels including 110, 140, and 170 r/min. The diameter of the stripping bar selected three levels including 240, 370, and 500 mm. The distance from the axis to the ear selected three levels including 100, 120, and 140 mm. The orthogonal test showed that the stripping mechanism worked best when the rotational speed was 110 r/min, the diameter of the stripping bars was 240 mm, and the distance was 100 mm from the axis to the ear. The grain broken rate was then 0.09%, the grain loss rate was 0.04% and the ear loss rate was 1.96%.
Number of references:19
Main heading:Grain (agricultural product)
Controlled terms:Agricultural machinery - Harvesting - Monomers - Speed - Testing
Uncontrolled terms:Corn - Grain moisture content - Mechanical analysis - Motion analysis - Orthogonal test - Rotational speed - Stripping mechanisms - Theoretical calculations
Classification code:423.2 Non Mechanical Properties of Building Materials: Test Methods - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.20.001
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 6>

Accession number:20145100353413
Title:Effect of drip irrigation and fertilizer application on water use efficiency and cotton yield in North of Xinjiang
Authors:Wu, Lifeng (1); Zhang, Fucang (1); Zhou, Hanmi (1); Suo, Yansong (1); Xue, Fengding (1); Zhou, Jianwei (2); Liang, Fei (2)
Author affiliation:(1) Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Area, Institute of Water-saving Agriculture in Arid Areas of China, Northwest A and F University, Yangling, China; (2) Institute of Water and Soil Fertilizer, Xinjiang Academy of Agricultural Reclamation Sciences, Shihezi, China
Corresponding author:Zhang, Fucang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:137-146
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Water and fertilizer affect a range of physiological processes in the cotton crop and are key factors controlling cotton productivity and yield. Two-year experiments(2012 and 2013) were conducted to evaluate the effects of different fertigation regimes on cotton growth, yield, water use efficiency and partial factor productivity of fertilizers in Shihezi areas of Xinjiang. The fertilization treatment was based on different ratios of N - P<inf>2</inf>O<inf>5</inf> -K<inf>2</inf>O and the irrigation treatment was based on the crop evapotranspiration (ET<inf>C</inf>). Five fertilizer treatments were designed including 60% (F<inf>0.6</inf>), 80 (F<inf>0.8</inf>), 100% (F<inf>1.0</inf>), 120% (F<inf>1.2</inf>) and 140% (F<inf>1.4</inf>) of recommended rates with N (250)-P<inf>2</inf>O<inf>5</inf> (100) -K<inf>2</inf>O (50) kg/hm², and three irrigation treatments included 60% ET<inf>C</inf> (W<inf>1</inf>), 80% ET<inf>C</inf> (W<inf>2</inf>) and 100% ET<inf>C</inf> (W<inf>3</inf>). Irrigation amount was decided by a 20-cm inner diameter evaporation pan. Evaporation pan-crop coefficient in seedling, budding period and flowering period, boll opening period were 0.2, 0.4, 0.7 and 0.25, respectively. During the experiment, plant height, leaf area index and dry mass accumulation, and yield components were measured. Harvest index (HI), water use efficiency (ratio between yield/irrigation amounts, WUE) and partial factor productivity of fertilizer (PFP) were calculated. The results showed that compared to W<inf>3</inf>F<inf>1.0</inf>, plant height, LAI, effective bolls number per plant, seed cotton yield and quality of dry matter and WUE of W<inf>1</inf>F<inf>0.6</inf>, W<inf>1</inf>F<inf>0.8</inf>, W<inf>1</inf>F<inf>1.0</inf>, W<inf>1</inf>F<inf>1.2</inf> and W<inf>1</inf>F<inf>1.4</inf> treatments have dropped significantly. Besides W<inf>2</inf>F<inf>0.6</inf> in 2013, W<inf>2</inf> and W<inf>3</inf> irrigation level under various fertilizer treatments, plant height were between 60 and 71 and LAI were between 3.4 and 4.2. The effective bolls number per plant of W<inf>3</inf>F<inf>1.0</inf>, W<inf>3</inf>F<inf>1.2</inf> and W<inf>3</inf>F<inf>1.4</inf> treatments were above 6.8 per plant. Cotton effective bolls number per plant was more sensitive than the 100-boll weight. In 2012 and 2013, the irrigation amount ranged from 291 to 445 mm and from 267 to 392 mm, cotton ET ranged from 277 to 419 mm and from 316 to 438 mm, WUE ranged from 1.27 to 1.65 kg/m³ and from 1.27 to 1.52 kg/m³ in 2012 and 2013, respectively. The highest seed cotton yield was obtained in the combination treatments of W<inf>3</inf>F<inf>1.2</inf> and W<inf>3</inf>F<inf>1.0</inf> with the value of 5 896 and 5 888 kg/hm² in 2012 and 2013, respectively. W<inf>2</inf>F<inf>1.0</inf> combination treatment had the highest WUE. PFP decreased with the increase of fertilization rate but increased with the increased irrigation amount and W<inf>3</inf>F<inf>0.6</inf> combination treatment had the highest PFP. Considering the water shortage condition in the northern Xinjiang Uygur Autonomous Region, the treatment of 80% ET<inf>C</inf> combined with 250-100-50 kg/hm² (N-P<inf>2</inf>O<inf>5</inf>-K<inf>2</inf>O) was suggested to be optimal for cotton production since the treatment could save 63 to 77 mm irrigation amount while keeping 95% seed cotton yields compared with the treatment of 100% ET<inf>C</inf> combined with 250-100-50 kg/hm² (N-P<inf>2</inf>O<inf>5</inf>-K<inf>2</inf>O). The saved water accounted for more than half amount of the averaged precipitation in this area. The study can provide valuable information for improving management of cotton crop in North of Xinjiang.
Number of references:29
Main heading:Cotton
Controlled terms:Crops - Efficiency - Evaporation - Evapotranspiration - Experiments - Fertilizers - Irrigation - Productivity - Seed - Subirrigation  - Water supply
Uncontrolled terms:Combination treatments - Crop evapotranspiration - Dry mass - Partial factor productivity - Physiological process - Water use efficiency - Xinjiang Uygur autonomous region - Yield
Classification code:446.1 Water Supply Systems - 802.3 Chemical Operations - 804 Chemical Products Generally - 821.3 Agricultural Methods - 821.4 Agricultural Products - 901.3 Engineering Research - 913.1 Production Engineering
DOI:10.3969/j.issn.1002-6819.2014.20.017
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 7>

Accession number:20145100353426
Title:Characteristics of biogas producing by anaerobic co-digestion of agricultural straw and swine wastewater based on improved straw-bed bioreactor
Authors:Chen, Guangyin (1); Du, Jing (1); Chang, Zhizhou (1); Ye, Xiaomei (1); Xu, Yueding (1); Zhang, Jianying (1)
Author affiliation:(1) East China Scientific Observing and Experimental Station of Development and Utilization of Rural Renewable Energy, Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, China
Corresponding author:Chang, Zhizhou
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:244-251
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Agricultural straw and livestock wastewater were the main source of agricultural contaminant, how to reduce, reuse and recycle these wastes has become more and more important. Anaerobic digestion is an attractive technique for bio-waste treatment which can produce biogas and bio-fertilizer. Co-digested two and more wastes is beneficial for anaerobic digestion. By this way, we can not only get more biogas, but also reduce the investment of biogas plant. Two or more agricultural wastes were converted to biogas in one anaerobic bioreactor. Although much work has been done on anaerobic co-digestion of two or more bio-wastes, but most work was done with batch model and there was no report on anaerobic co-digestion of agricultural straw and livestock wastewater. In pig farming, swine wastewater is the main contaminant and is generated every day, so swine wastewater must be added to the anaerobic digester daily, which means that we must use semi-continuous feeding bioreactor in a pig farm biogas plant. In this study, the feasibility of straw-bed anaerobic bioreactor (SAB) was investigated. In the straw-bed bioreactor, baling straw was used as the stationary phase and swine wastewater was used as the mobile phase, and a wastewater advanced anaerobic bioreactor (USR) was connected to the posterior of the straw-bed bioreactor. The results showed that the straw-bed anaerobic digestion system (SADS) was feasible and there was no significant difference between co-digestion and mono-digestion of straw and swine wastewater. The total solid biogas yield of straw of SAB and mono-digestion were 394.96 and 382.11 mL/g, respectively. Compared to mono-digestion, the stability of daily biogas yield and average methane content of co-digestion was improved significantly. The average methane content of SADS, baling straw and swine wastewater digested alone were 57.40%, 47.32% and 60.37%, respectively. The volumetric biogas production was also improved significantly and the volumetric biogas production of treatment of baling straw and swine wastewater digested alone were 69.42% and 66.94% to that of SADS. After 35 days reaction, air permeability of baling straw was decreased which leading to more serious floating of baling straw and short flow of influent. After that, COD content of effluent increased sharply and then maintained at higher level. Meanwhile daily biogas yield of wastewater advanced anaerobic bioreactor increased sharply. Therefore, it is necessary to connect a wastewater advanced anaerobic bioreactor to the posterior of straw-bed bioreactor in order to deep purification of effluent of SAB. The above results indicated that co-digested baling straw and swine wastewater in straw-bed anaerobic digestion system is feasible and is beneficial for biogas production.
Number of references:19
Main heading:Anaerobic digestion
Controlled terms:Agricultural wastes - Agriculture - Bioconversion - Biogas - Bioreactors - Digestive system - Effluents - Fermentation - Loading - Methanation  - Methane - Straw - Wastewater reclamation - Wastewater treatment
Uncontrolled terms:Agricultural contaminants - Anaerobic bioreactors - Anaerobic co-digestion - Biogas production rates - Livestock wastewater - Organic loading rates - Semi-continuous feeding - Swine wastewater
Classification code:452.3 Industrial Wastes - 452.4 Industrial Wastes Treatment and Disposal - 461.2 Biological Materials and Tissue Engineering - 461.8 Biotechnology - 522 Gas Fuels - 672 Naval Vessels - 802.1 Chemical Plants and Equipment - 802.2 Chemical Reactions - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.5 Agricultural Wastes
DOI:10.3969/j.issn.1002-6819.2014.20.030
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 8>

Accession number:20145100353428
Title:Comparation on cost and energy consumption with different straw's collection-store-transportation modes
Authors:Xu, Yayun (1); Tian, Yishui (1); Zhao, Lixin (1); Yao, Zonglu (1); Hou, Shulin (3); Meng, Haibo (1)
Author affiliation:(1) Rural Energy and Environmental Research Institute of Chinese Academy of Agricultural Engineering, Beijing , China; (2) Key Laboratory of Energy Resource Utilization from Agricultural Residues, Ministry of Agriculture, Beijing , China; (3) College of Engineering of China Agricultural University, Beijing, China
Corresponding author:Tian, Yishui
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:259-267
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to select appropriate mode of crop straw's collection-storage-transportation, and promote the large-scale use of straw resources, the mathematical model about straw's collection, storage and transportation was established, which was based on the equipment, manpower, and cost on the North China Plain. By analyzing different modes about straw's collection-storage-transportation (which was divided into centralized model, decentralized mode; collected by manpower, collected by machinery), the effect of cost and energy consumption were different. Because of the different amounts of straw collection, manpower and equipments were demanded in mathematical models. The results showed that the cost of straw's collection-storage-transportation was 120- 260 Yuan/t, the fuel consumption of straw's collection-storage-transportation was 1.2&times;10⁵ - 5.5&times;10⁵ kJ/t. While using machinery to collected straw in filed, the cost was lower than that by manpower; but the required equipment number was significantly more than thatneeded by manpower. Meanwhile, the energy consumption of equipment was significantly increased. On the contrary, collecting straw in filed by manpower needs a lot of manpower. The calculated results showed that the cost and energy consumption of centralized mode about equipment-manpower- cost was lower than decentralized mode when collecting by the same manner. Compared to the manpower collection, collection by machinery can reduce the total cost, but the initial investment was higher and the capacity in solving employment problem was lower. When the amount of crop straw collection increased from 5&times;10⁴ to 50&times;10⁴ t, the unit cost of mode A and B was monotonically increasing. As to mode C and D, it declined quickly from 5&times;10⁴ to 25&times;10⁴ t, then rose gradually from 25&times;10⁴ to 50&times;10⁴ t. Therefore, it can be concluded that the collection methods affected cost extremely. Collecting straw by manpower, the mode of A and C curved intersect at 250 000 t; Or else, the mode of B and D curved intersect at 500 000 t. When the collected amount of crop straw increased from 5&times;10⁴ to 50&times;10⁴ t, the unit energy consumptions of mode A and B increased, with slow upward trend rate; On the contrary, from 5&times;10⁴ to 25&times;10⁴ t straw collection, the unit energy consumption of mode C and D was decreasing, when the collected amount of crop straw was 18&times;10⁴ and 12&times;10⁴ t, the unit energy consumption curves of mode B and C2 could intersect; Similarly, the unit energy consumption curves of mode A2 and C1 also could intersect. In this circumstance, when the collected amount was less than the intersection, the energy consumption of mode B and A2 was lower than mode C2 and C1. Therefore, the energy consumption of centralized mode is lower when the crop straw amount collected is less, it is recommended to choose centralized mode; Otherwise, decentralized mode is the better choice.
Number of references:23
Main heading:Energy utilization
Controlled terms:Costs - Crops - Energy storage - Equipment - Fuel storage - Investments - Machinery - Mathematical models - Models - Refuse collection  - Straw - Transportation
Uncontrolled terms:Centralized models - Collection methods - Crop straws - Employment problems - North China Plain - Storage and transportations - Transportation mode - Upward trend
Classification code:431 Air Transportation - 432 Highway Transportation - 433 Railroad Transportation - 434 Waterway Transportation - 452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 522 Gas Fuels - 523 Liquid Fuels - 524 Solid Fuels - 525.3 Energy Utilization - 601 Mechanical Design - 702 Electric Batteries and Fuel Cells - 821.4 Agricultural Products - 821.5 Agricultural Wastes - 901 Engineering Profession - 902.1 Engineering Graphics - 911 Cost and Value Engineering; Industrial Economics - 911.2 Industrial Economics - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2014.20.032
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 9>

Accession number:20145100353433
Title:Dynamic modeling and parameters optimization of degrading ethylene by positive corona coupled with Ag-TiO<inf>2</inf>
Authors:Li, Liqin (1); Liang, Jialiang (1); Ye, Shengying (1); Chen, Xuemei (1); Song, Xianliang (1)
Author affiliation:(1) College of Food Science, South China Agricultural University, Guangzhou , China
Corresponding author:Ye, Shengying
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:306-312
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The quality of horticultural products in cold-storage environment rapidly declines due to its perishability. Ethylene is one of important factors to facilitate the perishing process, because it enhances the respiration intensity and enzymatic activities of horticultural products. We introduce the non-thermal plasma which were produced by positive corona into the horticultural cold-storage, it can remove the volatile organic gases effectively, safely, and stably. However, the corona generates much ozone that may poison fruits and vegetables. A more effectual method to use the non-thermal plasma is coupling it with heterogeneous catalysis technology. To explore the mechanism and kinetics of ethylene degradation and ozone regulation in the photoelectric catalyzed coupling reaction system of direct current positive corona-elemental silver deposit nanometer TiO<inf>2</inf>. In this paper, the cylinder wall was used as corona discharge reactor, with needle-array-versus- inner-cylinder-wall corona electrode, and with nano-TiO<inf>2</inf> as catalysis deposited with nanometer silver. The impacts of silver doping amount, discharge power and gas flow rate and other factors on ethylene degradation and ozone control effect were carried out in the simulation of the horticultural products cold storage environment, verified the intrinsic kinetics of the reaction process by surveying the changes of concentration of ethylene as well as ozone. The results showed that ethylene degradation dynamics model of positive corona discharge coupling activated carbon fiber (ACF) supported Ag doped nano-TiO<inf>2</inf> (Ag-TiO<inf>2</inf>/ACF) was established. Corona discharge coupling Ag-TiO<inf>2</inf>^*/ACF catalytic membrane on degradation of ethylene and control of the ozone concentration has a superior performance by comparing the reaction constant of Runge Kutta method for solving differential equations and least square method for dynamics model. By means of quadratic rotary combination experiment and regression fitting, quadratic multinomial model of reaction constant of corona discharge coupling Ag-TiO<inf>2</inf>^*/ACF catalytic membrane on the degradation of ethylene and the limits of predicted values of ozone concentration was established. The validity of the model was verified, and parameters of reaction system were optimized at the same time. The optimal conditions for storage of apple was that silver doping amount of 0.5%, discharge power of 0.47 W and gas flow rate of 400 L/h. The research can provide a reference for the technology of direct current positive corona discharge coupling nano-TiO<inf>2</inf> in the application of storage and transportation equipment of horticultural products.
Number of references:22
Main heading:Ethylene
Controlled terms:Activated carbon - Carbon fibers - Catalysis - Cold storage - Cylinders (shapes) - Differential equations - Electric corona - Electric discharges - Energy storage - Enzyme kinetics  - Flow of gases - Flow rate - Kinetics - Least squares approximations - Ozone - Reaction kinetics - Runge Kutta methods - Silver - Silver deposits - Titanium dioxide
Uncontrolled terms:Corona discharge reactors - Degradation dynamics - Fruits and vegetables - Horticultural products - Mechanism and kinetics - Parameters optimization - Positive corona - Storage and transportations
Classification code:408.2 Structural Members and Shapes - 547.1 Precious Metals - 631 Fluid Flow - 631.1.2 Gas Dynamics - 694.4 Storage - 701.1 Electricity: Basic Concepts and Phenomena - 702 Electric Batteries and Fuel Cells - 802.2 Chemical Reactions - 804 Chemical Products Generally - 921.2 Calculus - 921.6 Numerical Methods - 931 Classical Physics; Quantum Theory; Relativity
DOI:10.3969/j.issn.1002-6819.2014.20.037
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 10>

Accession number:20145100353407
Title:Effects of roots and salinity on law of development for farmland soil desiccation crack
Authors:Zhang, Zhanyu (1); Zhu, Wenyuan (1); Zhu, Lei (2); Wang, Ce (1); Sheng, Liting (1); Chen, Yu (1)
Author affiliation:(1) College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, China; (2) School of Civil Engineering, Ningxia University, Yinchuan, China
Corresponding author:Zhang, Zhanyu
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:83-89
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil shrinkage cracks which come into being with consumption and evaporation of water, cause changes in soil infiltration capacity and lead to the preferential migration of soil water and solute. To investigate the development law of desiccation cracks on the soil surface under the condition of different roots and salt contents, a set of method, based on digital image processing, was proposed to extract the crack geometry parameter, which greatly improved the efficiency and accuracy of image processing, and then researched the crack morphology variation with water content. In this paper, a laboratory dry test was carried out in the view of root content and soil content of soil samples. It was concluded that when the mass water content &gt;30%, there was little difference among the crack area density of the soil samples with different root length densities. As the mass water content continued to reduce, the crack area density increased gradually, and reached the maximum and kept stable when the mass water content reduced to 10% or so. The influences of different root length densities on the crack area density were quite different (P&lt;0.05), the greater the root length density was, the more obvious the role of root to anchor the soil was, and the smaller the soil crack area density was. When the mass water content &gt;30%, the crack length densities of soil samples with different root length densities all grew fast with the reduction of mass water content, but with little difference. As the moisture content continued to reduce, the greater the root length density was, the greater the crack length density was, and significantly different (P&lt;0.05). And the crack network connectivity index gradually dwindled with the root length density increased. The soil crack area density of the soil sample with a salt content of 2.0% was obviously greater than the soil crack density of the soil samples with other salt content in the whole drying process. When the moisture content was between 27% and 34%, there were little difference among the crack area density with a salt content of 0.5%, 1.0%, 1.5%, respectively, but were all greater than the crack area density of the control group, namely the soil sample with a salt content of 0. As the moisture content continued to reduce, the influences of different salt contents on the soil crack area density became more and more obvious. Soil crack area density and length densities of different salt contents were all significantly different (P&lt;0.05), and it indicated that the greater the salt content was, the larger the soil crack area density was, when the crack network got stable, and the smaller the length density was. Also, the greater the salt content was, the greater the network connectivity index was, and when the salt content got 2.0%, the network connectivity index was 1, which is the maximum value in theory, namely, there was no single-linkage crack. The research results have important practical significance for guiding cracked soil irrigation.
Number of references:18
Main heading:Cracks
Controlled terms:Driers (materials) - Image processing - Moisture determination - Soil moisture - Soil surveys - Soils
Uncontrolled terms:Desiccation cracks - Mass water contents - Network connectivity - Research results - Root content - Root length density - Salinity measure - Soil infiltration
Classification code:421 Strength of Building Materials; Mechanical Properties - 483.1 Soils and Soil Mechanics - 741 Light, Optics and Optical Devices - 803 Chemical Agents and Basic Industrial Chemicals - 944.2 Moisture Measurements
DOI:10.3969/j.issn.1002-6819.2014.20.011
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 11>

Accession number:20145100353429
Title:Comprehensive index model building of cultivated land yield and productivity based on improved agro-ecological zoning method
Authors:Chen, Li (1); Hao, Jinmin (1); Ai, Dong (1); Zhu, Chuanmin (1); Zhou, Ning (1); Hong, Shuman (1)
Author affiliation:(1) College of Resources Environmental Sciences, China Agricultural University, Beijing, China; (2) Key Laboratory for Agricultural Land Quality Monitoring and Control, The Ministry of Land and Resources, Beijing, China; (3) College of Geosciences, East China Institute of Technology, Nanchang, China
Corresponding author:Hao, Jinmin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:268-276
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Study on the relationships between grain production and cultivated land productivity and its regional difference is of great significance for food security. Besides, it is also important for finding regional potential yields of grain, improving the utilization efficiency of cultivated land resources and achieving the regional increase of grain yield. In this paper, on the basis of agro-ecological zoning (AEZ) model, a new method was proposed to calculate the cultivated land productivity under cultivated land quality modification. Furthermore, the modification of cultivated land quality was based on a new concept that the quality of cultivated land was not only affected by natural factors but also by artificial factors such as irrigation canals, greenhouse, nursery factory, mechanical facilities and its supporting service station. By discussing the conceptual system of cultivated land integrated productivity which took the potential quantity of cultivated land and the quality index of cultivated land into the consideration, we proposed that comprehensive productivity of cultivated land was the maximum sustainable production capacity for food under the certain economic and technological conditions, and it was strongly affected by the quality and quantity of cultivated land. Additionally, according to the concept, we built a model which can reveal the relationship between grain production and cultivated land productivity. This model was made up of comprehensive yield and productivity index of cultivated land (CLYPCI), cultivated land quality productivity index (CLQLPI), and cultivated land quantity productivity index (CLQNPI). The CLYPCI was used to measure the efficiency of cultivated land grain production and to reveal the relationship between actual output of grain and cultivated land productivity in a particular area. The CLQLPI was used to describe the average output efficiency of a regional cultivated land. The CLQNPI was used to measure the degree of exploitation and utilization of cultivated land in terms of quantity. This model was constructed based on the improved AEZ model, so it was only suitable for researching the relationship between grain production and cultivated land productivity at large or medium scales. At last, in this paper Quzhou county was used as a case study for model validation. The value of CLYPCI, CLQLPI and CLQNPI was 0.16, 0.31, 0.99, respectively in Quzhou. The results showed that the output efficiency and the average development level of cultivated land were not high in general. The potential of increased quantity of cultivated land was low, but the potential of increased yield of cultivated land was high. Compared with the cultivated land comprehensive productivity (CLCP), the CLYPCI value of different towns was reduced with CLCP which was sorted from the largest to smallest except Disituan town. The output of cultivated land was proportional to its productive capacity by comparing CLCP and CLYPCI of various towns. In addition, the value of CLQLPI and CLQNPI of different towns were very similar. The CLQLPI of 10 towns fluctuated around 0.31 which was the average value of CLQLPI of Quzhou. The CLQLPI in Yizhuang was the highest. The CLQNPI of 10 towns fluctuated around 0.99 and there were six towns whose CLQNPI value was 0.99. The CLQNPI of Yizhuang was also the highest. There was little chance to increase the quantity of cultivated land for Yizhuang.
Number of references:31
Main heading:Land use
Controlled terms:Agriculture - Ecology - Efficiency - Food supply - Grain (agricultural product) - Irrigation canals - Models - Productivity - Zoning
Uncontrolled terms:Comprehensive indices - Cultivated land qualities - Cultivated lands - Productive capacity - Regional differences - Sustainable production - Technological conditions - Utilization efficiency
Classification code:403 Urban and Regional Planning and Development - 404.2 Civil Defense - 454.3 Ecology and Ecosystems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 902.1 Engineering Graphics - 913.1 Production Engineering
DOI:10.3969/j.issn.1002-6819.2014.20.033
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 12>

Accession number:20145100353403
Title:Test and analysis on flow separation in centrifugal pump impeller based on particle image velocimetry
Authors:Wu, Xianfang (1); Liu, Houlin (2); Yang, Hongbin (2); Tan, Minggao (2); Wang, Kai (2)
Author affiliation:(1) School of Energy and Power Engineering, Jiangsu University, Zhenjiang, China; (2) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, China
Corresponding author:Wu, Xianfang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:51-57
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:When centrifugal pumps work under small flow rate conditions, the flow separation usually occurs inside. The flow separation often leads to the instability of inner flow, which can make the pump performance worse and maybe cause huge damage to centrifugal pumps. To disclose the development of flow separation, the technique of Particle Image Velocimetry (PIV) was applied to measure the inner flow field in a centrifugal pump. A centrifugal pump, whose specific speed was 73, was selected as the research model. The designed flow rate was 27 m³/h, and the designed head was 11 m. The blade number of the impeller was 6 and the outlet diameter of the impeller was 198 mm. The inlet diameter of the volute was 220 mm and its inlet height was 33 mm. To meet the requirements of the PIV test, the impeller and the volute were all made of plexiglass. The flow fields in the pump under seven different flow conditions were tested and the unsteady PIV test, including 12 different times, was done at 0.2Q<inf>d</inf>. All the experiments were conducted in an open loop, which consisted of a reservoir open to air, a suction valve, a test pump, a discharge pipe, and a discharge valve. The inner flow test results were analyzed carefully. To quantify the analysis of the test, the angle of flow separation and the circulation intensity were introduced as two analysis parameters in the paper. The definitions of the two analysis parameters were also presented in detail. The test results at different flow rate conditions showed that there was no flow separation in the pump at the design condition. When the flow rate was smaller than 0.6Q<inf>d</inf>, the flow separation began to occur and the flow separation developed fully under 0.2Q<inf>d</inf>. With the decrease of flow rate, the separation bubble moved toward the middle position and the outlet of the impeller channel. The test results at different impeller positions indicated that a separation bubble will appear in the impeller channel when the impeller channel gets close to the cut-water of the volute. When the impeller channel gets through the cut-water, the separation bubble develops rapidly. The separation bubble will disappear gradually when the impeller channel is far away from the cut-water. The variation gradient of angle of flow separation near pressure side of the blade is larger than that near suction side. With the decrease of flow rate, the variation gradient of angle of flow separation in the channel increases gradually. The number of separation bubbles can be obtained exactly by quantitative analysis of the angle of flow separation. The quantitative analysis of circulation intensity displays that the effect of rotor-stator interaction on flow separation gets obviously weak after the impeller rotates 135 degrees. The circulation intensities of the three channels near the cut-water of the volute are bigger than that in other channels. The study in this paper shows that the angle of flow separation and the circulation intensity are very appropriate to analyze the flow separation in centrifugal pumps. The research results are useful for the design and optimization of centrifugal pumps, especially for pumps with low specific speed.
Number of references:20
Main heading:Flow separation
Controlled terms:Centrifugal pumps - Flow fields - Flow rate - Flow visualization - Image processing - Impellers - Pumps - Reservoirs (water) - Testing - Velocimeters  - Velocity - Velocity measurement
Uncontrolled terms:Centrifugal pump impellers - Design and optimization - Flow rate conditions - Impeller positions - Low specific speed - Particle image velocimetries - Rotor-stator interactions - Test and analysis
Classification code:423.2 Non Mechanical Properties of Building Materials: Test Methods - 441.2 Reservoirs - 601.2 Machine Components - 617 Turbines and Steam Turbines - 618.2 Pumps - 631 Fluid Flow - 631.1 Fluid Flow, General - 741 Light, Optics and Optical Devices - 931.1 Mechanics - 943.3 Special Purpose Instruments
DOI:10.3969/j.issn.1002-6819.2014.20.007
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 13>

Accession number:20145100353415
Title:GIS spatial interpolation compared with soil type method for estimating soil carbon storage
Authors:Zhao, Guangshuai (1); Li, Fadong (1); Li, Yunsheng (1); Li, Jing (2); Ouyang, Zhu (1)
Author affiliation:(1) Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing, China; (2) University of Chinese Academy of Sciences, Beijing, China
Corresponding author:Li, Fadong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:155-162
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil carbon (C), especially the soil organic carbon (SOC) plays an important role in maintaining food production and reducing greenhouse gas emissions, and thus a better understanding of the spatial variability of SOC stocks is of great significance for the regional ecological environment and development of sustainable agriculture. Previous studies on SOC estimates were more conducted in larger scale, and the results often appeared quite different due to the amount of sampling, calculation methods and the complexity of the regional variation in environmental factors. Simulation with spatial interpolation of geographic information system (GIS) method and soil type method were frequently applied to calculate the SOC stocks, but whether the calculation results of both methods were consistent was inconclusive. In this paper, three typical counties of Shandong Province (Pingyi county, Yucheng county and Laiyang county) were selected as an example. We collected 208 soil profiles from three typical counties, including 71 profile points in Pingyi county, 69 profile points in Laiyang county and 68 profile points inYucheng county, and each soil sampling was collected with 3 duplicates. Through field sampling and analysis, SOC stocks were calculated with spatial interpolation simulation of GIS and soil type method respectively, and spatial distribution of soil organic carbon density (SCD) was analyzed, and further the results of county scale C stocks calculated by the GIS simulation method and soil type calculation method were compared to verify the applicability of GIS spatial interpolation simulation, and then to provide the basis for calculation of the C stocks in soil type classification missing areas or land change high frequency regions. The results indicated that: 1) The calculation results of SOC stocks in 0-20 cm soil layer with the two methods in the three typical counties were 3.88, 3.93, 3.54, 3.57, 2.78, 2.86 Tg respectively, while SCD in 0-20 cm soil layer are 2.2, 2.23; 2.08, 2.1, 2.74², 2.82 kg/m². Pingyi county ranked first in SOC stocks, and then was Laiyang county, Yucheng county. However, the SCD of Yucheng county was larger than the other two counties. The SCD value in plains was significantly higher than that in hills or plain-hills transition region, caused by differences of terrain and agricultural management. 2) The calculation results of C storage in the county scale with two methods were almost consistent (the maximum relative error did not exceed 3%, and the mean relative error was 1.7%) on condition that the sample met a certain amount but the simulation with spatial interpolation based on GIS method highlighted the SCD spatial distribution characteristics and spatial gradients law, and was more conducive to analyze the impact of different factors on spatial distribution of the SCD. 3) In calculating the county scale distribution of C storage, soil type method ignores a large diversity of soil types and soil details, while GIS spatial interpolation not only considered the spatial variability of soil inside, but also has a advantage of simplicity, easy to operate, and good visibility. The SCD value of the same soil subclasses in the counties makes a great difference, so the weight of main affecting factors should be defined when clustered to a larger area with soil type method.
Number of references:30
Main heading:Soil surveys
Controlled terms:Agriculture - Carbon - Gas emissions - Geographic information systems - Greenhouse gases - Information systems - Interpolation - Landforms - Organic carbon - Soils  - Spatial distribution
Uncontrolled terms:Agricultural management - Distribution characteristics - Ecological environments - Environmental factors - Maximum relative errors - Soil organic carbon densities - Soil types - Sustainable agriculture
Classification code:451.1 Air Pollution Sources - 481.1 Geology - 483.1 Soils and Soil Mechanics - 723.3 Database Systems - 804 Chemical Products Generally - 804.1 Organic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 903.2 Information Dissemination - 921 Mathematics - 921.6 Numerical Methods
DOI:10.3969/j.issn.1002-6819.2014.20.019
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 14>

Accession number:20145100353435
Title:Mathematical model and numerical simulation of biological porous medium during hot air drying
Authors:Wang, Huilin (1); Lu, Tao (1); Jiang, Peixue (2)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Beijing University of Chemical Technology, Beijing, China; (2) Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing , China
Corresponding author:Lu, Tao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:325-333
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Drying is a very important unit operation in many industries such as food, pharmaceuticals, chemicals and ceramics. In most cases, wet materials are dried by forced convection using hot air flow. Heat and mass transfer processes during drying have been studied by both experimental and numerical simulation methods. For the purpose of studying the mechanism of heat and mass transfer and stress-strain distribution during the hot air drying of biological porous medium, two-way coupled thermo-hydro-mechanical mathematical model has been developed to simulate the hot air convective drying process of biological porous media on basis of Fickian diffusion theory, Fourier's law of heat conduction and thermoelasticity mechanics. The following assumptions were made in order to find a solution to the hot air drying model: the biological porous medium was homogeneous and isotropic; the deformation during drying was elastic. The transient model, composed of a system of partial differential equations, was solved by finite difference methods. The computational procedure was programmed using C language. Some physical and mechanical properties of carrot changing with dry basis moisture content and temperature were considered. The numerical results were compared with available experimental data obtained during the drying of potatoes and carrots. The relative errors between numerical results and experimental data were both less than 5%, which showed the numerical results obtained using the mathematical model were in good agreement with the experimental data. Numerical simulations of the drying curve variations and the spatio-temporal distributions of moisture, temperature and drying stresses and strains of carrot were also evaluated. The temperature and moisture content showed a gradient inside carrot slice during drying. As the drying process proceeded, the temperature inside the carrot slice initially increased to reach the wet bulb temperature of the environment and eventually leveled off. The dry basis moisture content inside the carrot slice decreased, with the fastest decreased at the heat and mass transfer interface, eventually reached the equilibrium moisture content of the potato and leveling off. Both the moisture content gradient and the temperature gradient decreased gradually in the thickness direction. The normal stress was negative in all parts of the carrot slice, and the larger the closer to the evaporation interface. The shear stress was positive in all parts of the carrot slice, and the maximum shear stress occurred in the middle of the carrot slice. As in the case of the normal stress, the values of the normal strain were negative. The change trend of normal strain with time was consistent with that of moisture content. These results indicated that the observed physical deformations were caused by the dehydration of carrot slice during drying. The influence of drying conditions, such as air temperature, air velocity and the thickness of porous media on drying process was analyzed. Analysis showed that under certain drying conditions, the higher air temperature, the greater air velocity and the thinner slice thickness, the shorter drying time. This work should help in developing an understanding of the relationship between mass and heat transfer, shrinkage, stress, strains and physical degradation.
Number of references:21
Main heading:Computer simulation
Controlled terms:Air - Atmospheric temperature - Bioinformatics - C (programming language) - Chemical contamination - Computation theory - Couplings - Deformation - Differential equations - Drying  - Elasticity - Finite difference method - Food technology - Heat conduction - Heat convection - Mass transfer - Mathematical models - Moisture - Moisture determination - Numerical methods  - Numerical models - Porous materials - Shear stress - Solar dryers - Strain - Structural design
Uncontrolled terms:Equilibrium moisture contents - Heat and mass transfer - Heat and mass transfer process - Numerical simulation method - Physical and mechanical properties - Spatiotemporal distributions - Stress-strain - System of partial differential equations
Classification code:408.1 Structural Design, General - 421 Strength of Building Materials; Mechanical Properties - 443.1 Atmospheric Properties - 602 Mechanical Drives and Transmissions - 641.2 Heat Transfer - 641.3 Mass Transfer - 642.1 Process Heating - 723.1.1 Computer Programming Languages - 723.5 Computer Applications - 802.1 Chemical Plants and Equipment - 804 Chemical Products Generally - 822 Food Technology - 822.3 Food Products - 903 Information Science - 921 Mathematics - 944.2 Moisture Measurements - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.20.039
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 15>

Accession number:20145100353412
Title:Modeling soil water-salt dynamics and maize yield responses to groundwater depths and irrigations
Authors:Hao, Yuanyuan (1); Xu, Xu (1); Huang, Quanzhong (1); Huang, Guanhua (1)
Author affiliation:(1) Center for Agricultural Water Research in China, China Agricultural University, Beijing, China; (2) Chinese-Israeli International Center for Research and Training in Agriculture, Beijing, China
Corresponding author:Huang, Guanhua
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:128-136
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Reduction of water diversion from the Yellow River will intensify water shortage problems in the Yinbei Irrigation District (YID). Reasonable use of groundwater for irrigation is helpful to maintain the agricultural production. Groundwater exploitation may cause groundwater level declines in local areas. This helps to reduce the salinity accumulation in the root zone but decreases the capillary rise. Thus, it is important to figure out the responses of soil water-salt dynamics and crop yields to groundwater table fluctuations for salinity control and stable yields. In this study, HYDRUS-1D model was modified by coupling with the EPIC (erosion-productivity impact calculator) crop growth module for simulating agro-hydrological processes. The new crop module could simulate crop height, leaf area index (LAI), above-ground biomass and crop yield. The information between HYDRUS-1D and EPIC was exchanged by daily step. Root water uptake under water and salt stress was calculated with HYDRUS-1D and imported to EPIC to limit crop growth. EPIC module estimated crop height, LAI and root depth for HYDRUS-1D to calculate soil water-solute dynamics. HYDRUS-1D assumed that soil evaporation remained at the potential rate unless pressure head of the soil surface decreased to a prescribed value. After then this prescribed value was set as a constant head to renew the top boundary condition. However, it cannot reasonably reflect the decrease stage of soil evaporation when using the constant head boundary. This may overestimate soil evaporation. Therefore, a new soil evaporation module, estimating soil evaporation reduction coefficient using soil water content of the top layer (0-10 cm), was added for better describing the soil evaporation under shallow water tables. With the experimental data collected from the maize field in 2008, the model was calibrated by the data of groundwater irrigation treatment and validated by the data of canal irrigation treatment. Simulated soil water content and solute concentration in the root zone (0-90 cm) showed good agreement with the measured values. Root mean square error (RMSE), mean relative error (MRE) and coefficient of determination for soil moisture were 0.03 cm³/cm³, 3.4% and 0.78, respectively. For solute concentration, RMSE, MRE, coefficient of determination were 1.6 g/L, 1.3% and 0.29, respectively. LAI and above-ground biomass values were fitted well with the observations. MRE values for estimated and measured LAI and above-ground biomass were 5.9% and 10.6%, and R² were both larger than 0.95 for these two items. The model was then used to assess the impacts of groundwater table and irrigation changes on soil water-salt dynamics and maize yields. Nine groundwater depth (GWD) scenarios (100, 110, 125, 140, 155, 170, 185, 200 and 250 cm) and 6 irrigation treatments (0.6, 0.8, 1.0, 1.2, 1.4 and 1.6 times of the present irrigation) were considered. The results showed that soil water content and salt storage in the root zone declined with the reduction of groundwater level and irrigation amount. Due to the decrease of groundwater contribution and soil moisture, lowering groundwater depth resulted in a gradual increase of the average solute concentration in the root zone. Maize yields increased first and then decreased as the groundwater table declined. Generally, the maximum yields were achieved when GWD was between 140 and 155 cm. The maize yields may decrease with reducing the irrigation amount, therefore water-saving strategies were not recommended for local farmers with low incomes. Finally, the optimum groundwater depth of 140-155 cm was suggested, and three irrigations with an amount of 900 m³/hm² for each will be applied during maize growing period.
Number of references:23
Main heading:Water treatment
Controlled terms:Biomass - Crops - Digital storage - Dynamics - Ecology - Evaporation - Flood control - Groundwater - Groundwater resources - Growth (materials)  - Irrigation - Mean square error - Moisture determination - Plants (botany) - River diversion - Soil moisture - Soils - Water conservation - Water supply
Uncontrolled terms:Capillary rising - Crop growth - Groundwater irrigation - HYDRUS-1D - Irrigation districts
Classification code:441 Dams and Reservoirs; Hydro Development - 444 Water Resources - 444.2 Groundwater - 445.1 Water Treatment Techniques - 446.1 Water Supply Systems - 454.1 Environmental Engineering, General - 454.3 Ecology and Ecosystems - 461.9 Biology - 483.1 Soils and Soil Mechanics - 722.1 Data Storage, Equipment and Techniques - 731.1 Control Systems - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 931.1 Mechanics - 944.2 Moisture Measurements
DOI:10.3969/j.issn.1002-6819.2014.20.016
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 16>

Accession number:20145100353404
Title:Aerodynamic performance of discrete trailing edge flaps of wind turbine airfoil
Authors:Han, Zhonghe (1); Jia, Yalei (1); Li, Hengfan (1); Li, Qiuju (1); Liu, Huaxin (1); Zhu, Xiaoxun (1)
Author affiliation:(1) Key Lab of Condition Monitoring and Control for Power Plant Equipment Ministry of Education, North China Electric Power University, Baoding , China; (2) Hebei Software Institute, Baoding, China
Corresponding author:Han, Zhonghe
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:58-64
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to increase the wind capture ability of the wind turbine, many research studies on the lift enhancement method of the wind turbine airfoil have been conducted by scholars at home and abroad. An airfoil with tailing edge flaps has a much higher lift-to-drag ratio than an airfoil without trailing edge flaps. Among all the lift enhancement methods of trailing edge flaps, the structure of the wind turbine airfoil with discrete trailing edge flaps is simple, the cost of production is low, and it can easily achieve variable angle control. But the aerodynamic performance of the wind turbine airfoil with traditional discrete trailing edge flaps has not been comprehensively studied, and gaps between the flaps and the airfoil main body has an influence on the aerodynamic performance of the airfoil. So it is necessary to optimize the gap structure and study the aerodynamic performance of the discrete trailing edge flaps with different deflection angles. Taking a wind turbine airfoil S809 as the research object, the structure of the discrete trailing edge flaps was designed, the chord length was set as 1 000 mm, and the gap between the flap and the main body of airfoil was optimized to make the width of gap an even 1 mm. Then the trailing edge flaps model was established. The flap rotates around the rotate center to form a different flap model at different deflect angles, the deflect angles of the flap varied from 0-16&deg;, and the step size was 2. Mesh generation software Gambit s used to generate a model mesh, and the grids near the trailing edge were refined. After comparing the three kinds of grid number models, the grid independence was verified, and the number of a 148000 grid model for a calculating model was determined. The k-&omega; two equation turbulence model of Commercial software FLUENT was used here to calculate the aerodynamic performance of the airfoil S809 without flaps, and the result was compared with the experimental data. The result showed that when the attack angle is small, the error of lift coefficient is less than 0.9%, the error of drag coefficient is less than 4.86%, and the pressure coefficient distributions of calculated model is in good agreement with the experimental data. All these data verified that the calculated method was right and reliable. And then the aerodynamic performance of the 10% chord length flaps with different deflection angle under the attack angle of 0&deg; was studied with the same method. The pressure contours, streamline and pressure coefficient distribution around the model with discrete trailing edge flaps were calculated and analyzed theoretically. The result showed that the gaps between the flap and the main body of airfoil were reasonably designed, and that the gaps had little influence on the aerodynamic performance of the airfoil. So the influence of the gaps can be ignored here. The deflect angle of the discrete trailing edge flaps had much influence on the aerodynamic performance of the model. With the increase of the deflect angle, the camber of airfoil was increased, this made the airflow near trailing edge of airfoil deflected downward, the velocity of airflow near the upper surface of airfoil increased, this result in the pressure of the upper surface of airfoil decreased, and the pressure of the lower surface of airfoil decreased, then the pressure difference between the upper and lower surface was also increased, eventually leading to enhancement of the lift coefficient and the lift-to-drag ratio of the airfoil with discrete trailing edge flaps. When the deflection angle was 14&deg;, the lift-to-drag ratio of the airfoil reached the highest. The drag of the airfoil decreased with the increase of attack angle at first and then increased with the increase of attack angle. When the attack angle was 4&deg;, the drag was the smallest.
Number of references:21
Main heading:Turbine components
Controlled terms:Air - Airfoils - Computational fluid dynamics - Drag - Electric power transmission networks - Flaps - Lift - Lift drag ratio - Turbulence models - Wind turbines
Uncontrolled terms:Aero-dynamic performance - Commercial software - Lift-to-drag ratio - Pressure coefficient distribution - Pressure differences - Trailing edge flaps - Two-equation turbulence models - Wind turbine airfoils
Classification code:443.1 Atmospheric Properties - 615.8 Wind Power (Before 1993, use code 611 ) - 617 Turbines and Steam Turbines - 651.1 Aerodynamics, General - 652.1 Aircraft, General - 703.1 Electric Networks - 804 Chemical Products Generally - 921.6 Numerical Methods
DOI:10.3969/j.issn.1002-6819.2014.20.008
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 17>

Accession number:20145100353420
Title:Vertical movement characteristics of tuna (Thunnus albacares) in Pacific Ocean determined using pop-up satellite archival tags
Authors:Zhang, Heng (1); Dai, Yang (1); Yang, Shenglong (1); Wang, Xiaoxuan (1); Liu, Guangming (2); Chen, Xuezhong (1)
Author affiliation:(1) Key Laboratory of Fisheries Resources Remote Sensing and Information Technology Resources, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China; (2) Research Institute of Marine Affairs and Resource Management, Taiwan Ocean University, Taiwan
Corresponding author:Chen, Xuezhong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:196-203
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Pacific yellowfin tuna (Thunnus albacares) is widely distribute in subtropical and tropical waters, extending to 40&deg;N in the North Pacific Ocean. Understanding the biology of tunas requires the knowledge of where it lives and its various movements between different habitats. But, the movement and habitat of yellowfin tuna in the Northwest Pacific Ocean have been poor understood in the world. A total of 36 yellowfin tunas Thunnus albacares were tagged using Pop-up Satellite Archival Tags (PSATs) and released in 2010-2012 to examine their vertical movement patterns. The results showed that the return rate of 8 tunas deployed from purse seine fishery was 100%, but the recorded period of tags was only 0.5-5 days. The return rate of those tunas deployed from handline fishery was 75%, while the recorded period of tags was 0.5-91 days and the tag of 2 tunas were normally popped up. In this study, the recorded period was lower than 10 days for 18 tags, was 10-20 days for 3 tags and was longer than 20 days for 8 tags. The longest recorded time of fish ID 33339 was 91 days and its straight-line distance was 822 km from the deployed site. The second longest recorded time of fish ID 33869 was 89 days because of the 3 months set time, while its straight-line distance was only 10 km. The tunas deployed from handline fishery provided loner-time information. About 85.9% of time for yellowfin tunas lived in the 0-150 m depths, 13% of time in &ge;150-250 m and only 1.1% of time lived in the &ge;250 m depths. As for as water temperature, 81.7% of time yellowfin tunas lived in &ge;24, 16.2% of time in 16-24 and only 2.1% of time lived in &le;16. In 0-50 m depth, the occurrence frequency of yellowfin tunas in night was 2 times higher than that in day, while the occurrence frequency of them in day was larger than that in night in 50-500 m depths. From the most tags data, we found that the yellowfin tuna can go up to surface water layer (&lt;10 m) and the maximum habitat depth of 53.3% individuals both above 300 m. For example, the fish (tag 33869) have reach to 1 100 m water depth and the corresponding temperature only was 4.9. In the activity layer of yellowfin tunas, the minimum temperature of 80% of tuna were above 10, while the maximum temperature of tuna were more than 26. As a whole, the daily depth of yellowfin tuna was obviously deeper than the nightly depth at 23.5 m. About 87.5% individuals have the phenomenon of obvious diurnal vertical migration. In the whole, about 68% of individuals begun to move the shallow waters at dusk (18:00), and then they dived to relative deepwater at dawn (06:00). For example, the data of tag 33869 and 33882 showed that these two tunas have similar movement patterns in 24 hours. They both begun to dive deeper water layers from 5 to 6 clocks in the early morning, then maintain at the 60-160 m layer, and begun to rise to 20-50 m layer to habitat at dusk (17:00-18:00). In general, this preliminary study on the tag and release of yellowfin tuna has proved to be successful and can be used as a protocol for tagging study of tunas in the future.
Number of references:19
Main heading:Vitamins
Controlled terms:Ecosystems - Fish - Fisheries - Oceanography - Satellites - Surface waters - Temperature
Uncontrolled terms:Maximum temperature - Minimum temperatures - North Pacific Ocean - Pop-up satellite archival tags - Surface water layer - Vertical migration - Vertical movemen - Water temperatures
Classification code:444.1 Surface Water - 454.3 Ecology and Ecosystems - 461 Bioengineering and Biology - 461.7 Health Care - 471 Marine Science and Oceanography - 641.1 Thermodynamics - 655.2 Satellites - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 822 Food Technology
DOI:10.3969/j.issn.1002-6819.2014.20.024
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 18>

Accession number:20145100353402
Title:Optimal design of parallel-spool high-pressure solenoid valve
Authors:Dong, Dai (1); Li, Xiaoning (1); Guo, Zhonghua (1)
Author affiliation:(1) School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, China
Corresponding author:Li, Xiaoning
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:43-50
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:An underwater driving system requires a high-pressure solenoid valve with a high flow rate and high speed. A novel solenoid valve with parallel spools was proposed to meet the demand. The opening response time of the solenoid valve had a great influence on the performance of the underwater driving system. In order to reduce the opening response time of the novel parallel-spool pneumatic pilot operated high-pressure solenoid valve, an optimal design method was proposed. First, a mathematical model of the opening process of the valve was built up. A prediction model of the opening response time of the valve was deduced from the mathematical model established. In the prediction model, the opening response time was subdivided into four parts including the armature preparation time, the armature movement time, the exhaust time of the control chamber, and the movement time of the main valve spool. The corresponding formulas to solve the response time were derived. Secondly, based on the prediction model, an optimization program of the parameters of the pilot valve was designed by using a Multi-population Genetic Algorithm which was developed from a Standard Genetic Algorithm. The optimization program was written in MATLAB programming language using the Sheffield Genetic Algorithm Toolbox. To reduce the opening response time, four key parameters including the nominal diameter of the pilot valve, the radius of the armature, the width of the coil, and the length of the coil needed to be optimized. After optimization, the opening response time of the valve was 47.6 ms which was reduced by 14%. The impact of the key parameters on the opening response time of the valve was discussed respectively by using the optimization program. With the increase of the nominal diameter of the pilot valve and the length of the coil, the opening response time of the valve first decreases and then increases. Namely, there are optimal values for those two parameters. The opening response time fluctuated with the increase of the diameter of the armature, but the amplitude was small. Along with the rising of the width of the coil, response time was slightly decreased at first, then increased rapidly. On the basis of the analysis, multiple local extremums were found. That will result in many difficulties to the algorithm in converging to the global extremum. The optimization of the solenoid valve was an optimization with multiple local extremums. The optimization algorithm should possess a good capability to search for a global optimum. The optimization results obtained by using the Multi-population Genetic Algorithm showed that the optimization program designed was effective. Compared with the Standard Genetic Algorithm, the Multi-population Genetic Algorithm performed much better than the Standard Genetic Algorithm in avoiding the premature phenomenon, and its convergence speed was faster. At last, a test prototype of the novel valve was processed based on the optimized parameters and an opening response test of the valve was carried out. The experimental results showed that the opening response time tested was 48.3 ms at the pressure of 10 MPa, that was 1.5% larger than optimization result. The error between the experiment and the optimization was small. After optimization, the solenoid valve can meet the demands of the underwater driving system well.
Number of references:23
Main heading:Solenoid valves
Controlled terms:Algorithms - Design - Forecasting - Genetic algorithms - Mathematical models - MATLAB - Optimal systems - Optimization - Pneumatics - Reels  - Response time (computer systems) - Solenoids - Valves (mechanical)
Uncontrolled terms:Multi-population genetic algorithm - Optimal design - Optimal design methods - Optimization algorithms - Optimization programs - Optimized parameter - Standard genetic algorithm - Underwater driving
Classification code:408 Structural Design - 619 Pipes, Tanks and Accessories; Plant Engineering Generally - 632.3 Pneumatics - 704.1 Electric Components - 722.1 Data Storage, Equipment and Techniques - 722.4 Digital Computers and Systems - 921 Mathematics - 921.5 Optimization Techniques
DOI:10.3969/j.issn.1002-6819.2014.20.006
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 19>

Accession number:20145100353422
Title:Development of waste collection and water treatment system of cage culture in open waters
Authors:Jiang, Tao (1); Xu, Mingchang (1); Zeng, Zhi (3); Xu, Zhongwei (2)
Author affiliation:(1) Key Laboratory of Fishery Equipment and Engineering, Ministry of Agriculture, Shanghai, China; (2) Fishery Machinery and Instrument Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China; (3) Shanghai Hongcheng Industrial Development Co., Ltd., Shanghai, China
Corresponding author:Jiang, Tao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:211-218
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:At present, tail water generated by the cage culture contains a large quantity of residual feed, feces and other solid waste. If completely discharged, it will cause serious water eutrophication and severe damage for the ecological environment of culture waters. In view of the above question, the waste collection and waste treatment system of cage culture in open waters was developed for the cage culture reducing the tail water discharge and pollution into waters. This system is composed of the waste collecting device for collecting feed bait and fish feces, water supply and drainage system for water circulation into the closable cage, waste collection system for the scale of the cages and closable cages, filter for filtration to feed bait and fish feces and tail water processing system devices five parts. Compared with traditional net cage culture on water pollution, the waste collection and water treatment system of cage culture has four improvements: 1) Adding a dirt collecting bucket in each cage at the bottom, the solid waste together into the bucket, to facilitate the rapid promotion of waste collection. 2) In view of the traditional net cage waste collection, design sewage collection central gathering side lifting bucket apparatus; For a closable cage except with waste collection function, also has a deep water net cage will ascend to, bottom discharge function, with supreme and carry out the way water exchange, pneumatic recoil function, prevent the filter mesh is waste particles blocking. Water door with one-way flow function, prevent the back flow of sewage. 3) For solid waste water after filtration, using an ecological floating bed water pot of economic plants (such as Canna indica L., Acorus calamus L.) and microbial biofilm formation methods, nutrient rich water to fully absorb the water reach the discharge requirements. 4) The whole system adopts compressed air as the power source, centralized collection by using the method of pneumatic lifting implementation of waste water, centralized pneumatic depths can be a closed cage of ascension, as well as an aerated ecological floating bed. Waste collection in the running process of the system, collecting cage precipitation of tail water lifting and the air consumption, pressure has a very close relationship. The system of the waste collection tube with an inner diameter of PVC steel wire spiral reinforced hose 80 mm. 4.5 m under the water and gas water mixing chamber, namely air injection depth of 4.5 m. Through the test, in improving the sludge hopper in tail water, can be found through observation proposed by turbidity of tail water gradually becomes transparent, in this process, the 18 dirt collecting bucket of water statistics, the average sewage collection bucket lifting water is 0.34 m³. The results elaborated through professional transformation of large water cage facilities, constructed from the waste collection, solid-liquid separation, and the breeding of tail water after separation by ecological floating bed hanging membrane technology to physics and a set of ecological treatment system. The system collects the water discharged after treatment, the total phosphorus (TP), ammonia nitrogen (NH<inf>3</inf>-N), chemical oxygen demand (COD) were 0.305, 0.095, 16.2 mg/L, reached a `freshwater ponds water discharge requirements of ST9101-2007' II class standard. On the ammonia nitrogen and other indicators, the system realizes the standard exhaust culture of the tail water, greatly reducing the concentration of cage aquaculture wastewater to the water discharge.
Number of references:19
Main heading:Water pollution
Controlled terms:Ammonia - Aquaculture - Chemical oxygen demand - Compressed air - Emission control - Eutrophication - Fish - Membrane technology - Nitrogen - Oxygen  - Pneumatics - Sewage - Solid wastes - Waste treatment - Wastes - Water filtration - Water injection - Water supply - Water treatment - Wire
Uncontrolled terms:Cage - Ecological environments - Ecological floating beds - Emission reduction - Lifting implementation - Solid-liquid separation - Water supply and drainages - Water treatment systems
Classification code:445.1 Water Treatment Techniques - 446.1 Water Supply Systems - 451.2 Air Pollution Control - 452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 453 Water Pollution - 453.1 Water Pollution Sources - 461 Bioengineering and Biology - 471 Marine Science and Oceanography - 471.5 Sea as Source of Minerals and Food - 535.2 Metal Forming - 612.1 Internal Combustion Engines, General - 632.3 Pneumatics - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.3 Agricultural Methods - 822 Food Technology - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.20.026
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 20>

Accession number:20145100353405
Title:Numerical simulation of hydraulic performance on bidirectional flow channel of drip irrigation emitter using Fluent
Authors:Tian, Jiyang (1); Bai, Dan (2); Yu, Fuliang (1); Wang, Xinduan (2); Guo, Lin (2)
Author affiliation:(1) State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, China; (2) Institute of Water Resources and Hydroelectric Engineering of Xi'an University of Technology, Xi'an, China
Corresponding author:Bai, Dan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:65-71
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The hydraulic performance of bidirectional flow channel is better than the hydraulic performance of labyrinth-channel, especially in 0.05-0.10 MPa. So bidirectional flow emitter can save more energy and the drip irrigation tube can be thinner, it can reduce investment cost and has good application in irrigation. In this study, numerical simulation method was used to accurately and efficiently design various kinds of channels of drip irrigation emitters. In order to improve the efficiency of research and reduce the cost of development, Fluent was used to simulate the bidirectional flow channel and analyze the mechanism of energy dissipation. A channel was designed within a reasonable range of structural parameters to study the grid partition and model selection. The results showed that unstructured grid was suitable for numerical simulation of bidirectional flow channel. Mesh cell sizes of 0.1 mm, 0.2 mm and 0.5 mm were chosen to calculate the flux of the channel under different pressures. Mesh cell size 0.2 mm under the numerical simulation was more accurate and efficient than the ones of 0.1 mm and 0.5 mm. In this paper, five turbulence models including standard k-&Epsilon;, RNG k-&Epsilon;, realizable k-&Epsilon;, standard k-&omega; and SST k-&omega; were compared. The simulating results of realizable k-&Epsilon; and standard k-&omega; were better than that from other models. The correlation coefficients between the test results and the simulation values of these two models were 0.998 and 0.998, respectively, in 0.05-0.30 MPa. In 0.10-0.25 MPa, the simulation values were much closer to the test results. So Fluent can be used to simulate the water flow of the bidirectional flow channel and the simulation results had high precision. In addition, by orthogonal design method, we chose three key factors from the structural parameters and arranged nine experimental schemes to study the hydraulic performance and mechanism of energy dissipation. According to the main principle of the bidirectional flow channel, the flux of the backward flow to the flux of the forward flow ratio has important influence on hydraulic performance. For the different kind of channels, when the field angles of V-shape walls were the same, the higher the ratio, the better the hydraulic performance. For the same kind of channel, the higher the pressure was, the higher the ratio and the better the hydraulic performance. The flow index of the third experimental scheme was the smallest among the nine experimental schemes. The velocity vector distribution of the third experimental scheme showed flow conditions in bidirectional flow channel including high velocity area, low velocity area and mixing area of the forward flow and the backward flow. The pressure profile of the third experimental scheme showed the change of pressure in bidirectional flow channel, which further validated the mechanism of energy dissipation and the effect of energy dissipation. When the inlet pressure was 0.05 MPa, the pressure changed from about 0.042 MPa to 0.026 MPa at the mixing area of the forward flow and the backward flow, pressure drop was quite obvious. These conclusions can be directly used to improve the structure of bidirectional flow channel and promote the effect of energy dissipation.
Number of references:24
Main heading:Computer simulation
Controlled terms:Channel flow - Cost reduction - Energy dissipation - Flow of water - Inlet flow - Investments - Irrigation - Mixing - Numerical methods - Numerical models  - Turbulence - Turbulence models
Uncontrolled terms:Bi-directional flows - Correlation coefficient - Emitter - Hydraulic performance - Numerical simulation method - Orthogonal design method - Structural parameter - Velocity vector distribution
Classification code:525.4 Energy Losses (industrial and residential) - 631.1 Fluid Flow, General - 631.1.1 Liquid Dynamics - 723.5 Computer Applications - 802.3 Chemical Operations - 821.3 Agricultural Methods - 911.2 Industrial Economics - 921 Mathematics - 921.6 Numerical Methods
DOI:10.3969/j.issn.1002-6819.2014.20.009
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 21>

Accession number:20145100353424
Title:Performance analysis and experiment of solar hot water and pure water co-production system
Authors:Zhou, Xizheng (1); Ma, Chunyuan (1); Zhang, Liqiang (1); Wang, Peng (1)
Author affiliation:(1) National Engineering Laboratory for Coal-Fired Pollutants Emission Reduction, College of Energy and Power Engineering, Shandong University, Ji'nan, China
Corresponding author:Ma, Chunyuan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:228-235
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In this paper, the solar hot water and pure water co-production system was built and the mathematical model of energy conversion and transmission was established based on the system's operation, which aimed to improve the thermal performance and water productivity of the system experimentally and theoretically. The double evacuated tube solar collector was integrated into the desalination stills to ensure the continuity production of distillate. The evaporation-condensation tank and the heat storage water tank were designed and built with a &phi;58 mm&times;1.8 m&times;24 double evacuated heat pipe, a hot water tank capacity of 109.2 L, an evaporation area of 0.6235 m², a condensation water tank capacity of 124.8 L, a condensation area of 0.7092 m^2, and a heat storage water tank of 200 L. The governing energy balance equations were solved analytically with Matlab software and compared with the experimental results. The results indicated that water productivity and performance coefficient increased first and then decreased with the increase of temperature at a certain temperature range (50-70). It was found that the productivity of water and the coefficient of performance increased to a maximum at 60. The constant temperature (60) heat storage had a significant advantage in terms of superior performance as compared to quantitative heat storage at 60. The increments of the distilled water productivity, the total coefficient of performance, and the gained output ratio were 950 mL, 0.102 and 0.056 respectively. Furthermore, the system performance was conducted without heat storage. The distilled water productivity, the overall system coefficient of performance, and the gained output ratio were 5 978.4 mL, 1.2498 and 0.468, respectively. The decrease of the coefficient of performance and the gained output ratio were 0.1979 and 0.219, compared with constant temperature heat storage at 60. Finally, the water quality of the distilled water was also tested It was found that each parameter test result of water quality reached the standard of drinking water, including the sensory index, chemical index, bacteriological index, and toxicology index. The pH of distilled water was increased from 6.98 to 7.6, and its weakly alkaline properties excellently accorded with human body physiological needs. The chromaticity of the distilled water was reduced from 12 to 4.2, and chloride content and fluoride content were reduced from 360.3 to 2.5 mg/L and from 1.38 to 0.08 mg/L, respectively. The total hardness and total soluble solids were reduced from 275.62 to 4 mg/L and from 639.6 to 12 mg/L, oxygen consumption was decreased from 2.8 to 0.54 mg/L, the iron and manganese content had been reduced from 0.29 to 0.2 mg/L and from 0.16 to 0.04 mg/L as well, and total coliforms and toxicity index in water were not detected. The percent of pass of the system was obtained as 100%. The proposed method could be used to provide living hot water and drinking water for brackish water areas, coastal areas, and overseas islands, and has very good social and economic value.
Number of references:31
Main heading:Potable water
Controlled terms:Alkalinity - Chlorine compounds - Condensation - Cooling systems - Desalination - Economics - Evaporation - Heat pipes - Heat storage - Mathematical models  - MATLAB - Productivity - Solar energy - Temperature - Toxicity - Water quality - Water resources - Water tanks
Uncontrolled terms:Coefficient of Performance - Energy balance equations - Evacuated tube solar collector - Evaporation-condensation - Heat storage water tanks - Performance coefficients - System coefficient of performance - Total soluble solids
Classification code:444 Water Resources - 446.1 Water Supply Systems - 453.2 Water Pollution Control - 615.2 Solar Power - 641.1 Thermodynamics - 641.2 Heat Transfer - 801.1 Chemistry, General - 802.3 Chemical Operations - 804 Chemical Products Generally - 913.1 Production Engineering - 921 Mathematics - 971 Social Sciences
DOI:10.3969/j.issn.1002-6819.2014.20.028
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 22>

Accession number:20145100353398
Title:Mechanical dry direct-sowing modes improving growth, development and yield of rice
Authors:Sun, Yongjian (1); Zheng, Hongzhen (1); Xu, Hui (1); Yang, Zhiyuan (1); Jia, Xianwen (1); Cheng, Hongbiao (1); Ma, Jun (1)
Author affiliation:(1) Rice Research Institute of Sichuan Agricultural University / Key Laboratory of Crop Physiology, Ecology, and Cultivation in Southwest, Ministry of Agriculture, Chengdu , China
Corresponding author:Ma, Jun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:10-18
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to clarify yield formation mechanism of mechanical dry direct-sowing rice, the objective of this experiment was to study the effects of different mechanical dry direct-sowing modes on growth and development characteristics and yield of rice. Two different rice cultivars of indica hybrid rice F you 498 (143 days growth duration) and conventional japonica rice Xudao 4 (145 days growth duration) were planted with two mechanical dry direct-sowing modes, including a shallow rotary tillage land and mechanic drilling simultaneously (B<inf>1</inf>), regulating soil moisture and two rotary tillage before mechanic drilling (B<inf>2</inf>). Manual broad-cast sowing (B<inf>3</inf>) was set as control at the same time. We investigated and performed growth analysis during different growth periods, and determined yield formation and physiological characteristics under different direct-sowing treatments. The dry direct-sowing machine in this study was modified by Nanjing Agricultural University and was re-modified by Sichuan Agricultural University. This machine has six drills and sowed depth 2.0 cm, drill spacing 28.0 cm, working area 1.50 m. Motive power of this machine was the Shanghai New Holland tractor (SNH504). This test adopted row spacing 20 m &times; 1.5 m, each plot covered 30 m² of seeding amount was 30.0 kg/hm² of indica hybrid rice F you 498, 37.5 kg/hm² of conventional japonica rice Xudao 4 respectively. The nitrogen fertilizer amount was 180 kg/hm², and the amount of potash and phosphate were 90 and 180 kg/hm², respectively. The N application ratios was applied on 4 splits: 50% basal, 30% tillering fertilizer at the third leaf stage, 10% panicle N-fertilizer at the 4th leaves emerged from the top, 10% ear granular fertilizer at the full heading stage. The phosphate fertilizer was applied as base fertilizer. The potash fertilizer application ratio of basic fertilizer, tillering fertilizer and ear granular fertilizer was 2:1:1. The other management measures were at a uniform with high-yield cultivation. The results showed that the variety difference and direct-sowing modes significantly affected dry matter accumulation and leaf area index (LAI) at the mainly growth periods, net photosynthetic rate (Pn) and protective enzyme activities of flag leaves, root bleeding intensity, culm lodging resistance during the grain filling stage and the grain yield. Under different direct-sowing modes, the various indicators on yield and growth characteristics of F you 498 were significantly higher than those of Xudao 4. Compared with B<inf>3</inf> treatment, rice under mechanical direct-seeding modes could optimize the number of rice tillering, improve the percentage of earbearing tiller, maintain an appropriate LAI and increase efficient leaf area ratio at the full-heading stage. Besides mechanical direct-seeding could improve photosynthetic capacity at the grain filling stage and therefore increase the accumulation of photosynthetic products. In addition, Pn and protective enzyme activities in flag leaves, root bleeding intensity, culm lodging resistance during the grain filling stage under mechanical direct-seeding modes were superior, and rice could gain higher seed-setting rate and 1000-grain weight with a number of effective panicles. These outstanding traits should be the important reason for mechanical direct-sowing rice further to increase yield. Under different mechanical direct-sowing modes, compared with B<inf>3</inf>, B<inf>2</inf> treatment was the best model in this study referred as the mechanical direct-sowing treatments, which could further promote the dry matter accumulation, alleviate LAI decay, increase root vigor and the ability of culm lodging resistance during grain filling stage, consequently, promoting the seed-setting rate and 1000-grain weight as well as the grain yield.
Number of references:17
Main heading:Grain (agricultural product)
Controlled terms:Agricultural machinery - Crops - Cultivation - Drills - Enzymes - Filling - Grain growth - Growth (materials) - Nitrogen fertilizers - Phosphate fertilizers  - Plants (botany) - Potash - Potassium fertilizers - Soil moisture
Uncontrolled terms:Direct-seeding - Dry matter accumulation - Grain yield - Growth and development - Net photosynthetic rate - Photosynthetic capacity - Physiological characteristics - Rice
Classification code:461.2 Biological Materials and Tissue Engineering - 461.9 Biology - 483.1 Soils and Soil Mechanics - 603.2 Machine Tool Accessories - 691.2 Materials Handling Methods - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 933.1.2 Crystal Growth - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.20.002
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 23>

Accession number:20145100353411
Title:Effect of precipitation intensities on preferential flow and its numerical modeling
Authors:Wu, Qinghua (1); Zhu, Guosheng (1); Cui, Haodong (1); Zhang, Jiafa (1); Zhang, Fawang (2)
Author affiliation:(1) Changjiang River Scientific Research Institute, Wuhan , China; (2) Institute of Karst Geology, CAGS, Guilin, China
Corresponding author:Zhang, Fawang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:118-127
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The preferential flow is common in the soil with preferential paths, which affects soil water infiltration greatly. Although previous studies have made a great progress in preferential flow, the effect of preferential paths on preferential flow has not been reported, and a great effort is necessary to understand how precipitation intensities affect preferential flow. Therefore, in this paper, five undisturbed soil columns were sampled at the depth of 0-100 cm with different distribution of preferential paths from the Experimental Station of the Institute of Hydrogeology and Environmental Engineer, Chinese Academy of Geological Science (Hebei, China) and from Luancheng Experimental Station of Chinese Academy of Science (Hebei, China). Tests of different precipitation intensities, i.e., 0.23-0.24, 0.07-0.11, and 0.008-0.042 cm/min, were done to investigate preferential flow of the five soil columns. And the Hydrus-1D software coupling a dual-permeability model was applied to simulate the preferential flow of the soil columns under differential rainfall intensities. The results showed that the preferential paths played a vital role in development of the preferential flow since the levels of preferential flow were higher with more preferential paths in the soils. The relative transport abilities of preferential paths, which were defined by the ratio of velocity of preferential flow to rainfall intensity, increased with heavier rainfall. When the rainfall intensities were larger than the maximal coefficients of hydraulic conductivity of the intact soil columns, the velocities of preferential flow increased remarkably with increase of rainfall intensities. However, when the rainfall intensities were smaller than the maximal coefficients of hydraulic conductivity, the velocities of preferential flow increased little or no change. The effect of rainfall intensities on the &nu; and increased ranges of &nu; was related to the development of preferential paths in the intact soil columns, i.e., the effect can be stronger with the higher degree of preferential paths. In the soil columns with better development of preferential paths, the initial times of soil water flowing out at the bottom of the soil columns were shorter when rainfall intensities were larger, while in the soil columns with well developed preferential paths, the initial times of soil water flowing out at the bottom of the soil columns decreased firstly with a higher rainfall intensity, and then increased. The dual-permeability model described preferential flow well but couldn't simulate the process that soil water in the soil matrix flowed out horizontally to preferential paths after the rainfalls. As such the model was not suitable for the soils with plenty of soil fissures. The percentage of preferential flow obtained from the results of modeling was 93.6%-99.9%, which was in agreement with the tested results in undisturbed to disturbed soil. It suggested the model could simulate the preferential flow well. However, the results may be affected by size of columns since the characteristics of preferential flow varied with study scales. Therefore, further studies were needed to improve the understanding of preferential flow in larger scales. The results here will be useful to evaluate the groundwater recharge, water saving methods and movement of soil pollutants in arable land.
Number of references:31
Main heading:Soil testing
Controlled terms:Flowing wells - Groundwater flow - Groundwater pollution - Hydraulic conductivity - Hydrogeology - Pore structure - Rain - Recharging (underground waters) - Soil moisture - Soils  - Water - Water conservation
Uncontrolled terms:Dual-permeability models - HYDRUS-1D - Precipitation intensity - Preferential flows - Preferential path
Classification code:443.3 Precipitation - 444 Water Resources - 444.2 Groundwater - 481.1 Geology - 483.1 Soils and Soil Mechanics - 512.2.2 Natural Gas Deposits: Development Operations - 632.1 Hydraulics - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.3969/j.issn.1002-6819.2014.20.015
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 24>

Accession number:20145100353430
Title:Method of quantitative compensation for cultivated land conversion based on spatial characteristics of cultivated land protection value
Authors:Ren, Ping (1); Wu, Tao (1); Zhou, Jieming (1)
Author affiliation:(1) Key Lab of Land Resources Evaluation and Monitoring in Southwest, Ministry of Education, Sichuan Normal University, Chengdu , China; (2) Collaborative Innovation Center for Land Resource Development and Protection of Sichuan Province, Chengdu , China
Corresponding author:Zhou, Jieming
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:277-287
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Cultivated land is a type of fundamental and strategic resources for China. Therefore, cultivated land protection has become China's national strategy. Along with the economic development and the population increase, the occupation of cultivated land for urban construction purpose has been an inevitable tendency. The understanding about the value loss associated with the continuous diminution of cultivated land resource, and the corresponding compensation mechanism, has become critical for land conservation. This paper constructed a land-value-evaluation model, which was based on cultivated land value classification, integrating income capitalization method, equivalent substitution approach, and market value method. By using of this model, we estimated cultivated land protection values for 31 provinces/municipalities in mainland China. Further, by use of GIS techniques, the spatial characteristics for the cultivated lands' protection values over the entire country were quantitatively described. Then, the simulated compensation mechanism for cultivated land conversion was established. Such work offered innovative approaches for structuring the cultivated land protection policies and regional compensation mechanisms for cultivated land conversion. The results indicated that there was a significant regional difference associated with the cultivated land protection values. The highest value, 185.21&times;10⁴ Yuan RMB/hm², was at the Beijing city; while the lowest value, 44.61&times;10⁴ Yuan RMB/hm², was at Qinghai province. The former was 4.2 times of the latter. Second, there were certain spatial characteristics associated with the distribution of cultivated land protection values over the 31 provinces/municipalities in China. In detail, the economic values showed a tendency that the higher values were at Northeast/East regions while the West regions had the lower values. Such tendency was related with the different levels of economic development and conditions for agricultural production in different regions. But the social values showed a different tendency that higher values were at Middle/West regions. This tendency was resulted from the influences by the population, the natural conditions of cultivated land recourses, and the levels of socioeconomic development in different regions. Specifically, the pattern for the areas with high basic guarantee value, which was a specific type of social values, was relatively scattered. It was majorly related with the level of the area per capita of cultivated land resource in different regions. The employment security value, which was another specific type of social values, showed a tendency that was higher at the West while lower at the East. This was significantly influenced by the levels of socioeconomic development and the difference in resource endowment. The areas with high social stability value, which was the third type of social values, showed a scatter pattern as well. This was majorly resulted from the total amount of cultivated land and the levels of grain production in different regions. The ecologic service value presented a different spatial tendency that the higher values emerged at the Southeast regions while the North and Northwest regions possessed lower values. This tendency can be explained by the regions' natural ecological environments. Third, according to the regional compensation mechanism for cultivated land conversion established in this research, the central government, as one of the cultivated land protection agents, shall pay 26764.068&times;10⁸ Yuan RMB to all the provinces/municipalities in the year of 2012. Such payment shall be used for protecting the cultivated land for holding its functions such as social stability and ecological service. This approximately takes 5.15% of national GDP in that year. In detail, the sum of the benefits loss for cultivated land protection and the costs for the compensation of cultivated land conversion was 10.907&times;10⁸ Yuan RMB, 10.283&times;10⁸ Yuan RMB, 74.680&times;10⁸ Yuan RMB, 66.495&times;10⁸ Yuan RMB, and 8.529&times;10⁸ Yuan RMB for Shanghai city, Anhui province, Guangdong province, Guangxi province, and Ningxia province, respectively. Based on this theoretical model constructed in this paper, the benefits/costs of cultivated land conversion become a critical factor in the process between the central and local governments. The research also provides the theoretical and practical reference for a conversion of cultivated land protection mechanism, which will be good for land management in China.
Number of references:24
Main heading:Land use
Controlled terms:Agriculture - Compensation (personnel) - Conservation - Economic and social effects - Economics - Ecosystems - Geographic information systems - Models - Natural resources
Uncontrolled terms:Agricultural productions - Compensation mechanism - Cultivated lands - Ecological environments - Innovative approaches - Protection fund - Socio-economic development - Spatial characteristics
Classification code:403 Urban and Regional Planning and Development - 444 Water Resources - 454 Environmental Engineering - 454.3 Ecology and Ecosystems - 501 Exploration and Prospecting - 512 Petroleum and Related Deposits - 723.3 Database Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 902.1 Engineering Graphics - 912.4 Personnel - 971 Social Sciences
DOI:10.3969/j.issn.1002-6819.2014.20.034
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 25>

Accession number:20145100353399
Title:Multi-rotor aircraft attitude detection system based on fuzzy-proportion integration deviation correction
Authors:Liao, Yihua (1); Zhang, Tiemin (1); Liao, Yiyong (1)
Author affiliation:(1) Key Laboratory of Key Technology on Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou, China
Corresponding author:Zhang, Tiemin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:19-27
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Multi-rotor is an aircraft that can vertically takeoff, land and freely hover. It can be used as a platform to monitor field information near ground with remote sensing technology. It is a beneficial supplement to satellite remote sensing monitoring. Flight control is the core of the whole flight system and attitude detection is an important part of flight control. Therefore, real-time acquire accurate attitude information is the basis for its flight controlling. In this paper, taking multi-rotor as object, a multi-sensor attitude detection system was established. The system included STM32F103 as microprocessor, MPU6050 as three-axis gyroscope and accelerometer, HMC5883 as electronic compass. However, when vehicle accelerated horizontally, deviations among sensors would be produced because attitude angular could be measured by gyroscope timely, but accelerometer and electronic compass would lag due to the averaging. Moreover, accelerometer cannot distinguish any horizontal acceleration from gravity. In order to eliminate the measure deviations among above sensors, multi-sensor information fusion method with fuzzy-proportion integration (fuzzy-PI) deviation correction based on quaternion and its coordinate conversion was proposed. Fuzzy-proportion integration (fuzzy-PI) deviation correction method integrated precise performance of PI regulator and fast feature of fuzzy regulator. According to the vehicle at low or high speed motion, the deviations would be bigger or smaller. When the deviations and its integrations were less than the predetermined threshold value, it switched to PI regulator to obtain accurate measure. When they were greater than the predetermined threshold value, the algorithm switched to fuzzy regulator to correct the deviation as soon as possible. Attitude angle detected by fuzzy-PI deviation correction method, complementary filter algorithm and DMP program were validated by SGT320E multi-functional three-axis rotary platform. The measurement results were monitored and acquired through serial port. When roll angle ranged from -40&deg; to 40&deg;, static angle measurements were made. Experiment result showed that the average measure error of roll angle and pitch angle with the proposed method was 1.213&deg; and 1.072&deg;, less than complementary filter algorithm. It could satisfy the accuracy requirement in aircraft attitude detection. Furthermore, time consumption per attitude angle solution with above 3 methods running on the proposed multi-sensor attitude detection hardware system was recorded through timer in STM32 and their solution time consumptions were less than 1ms, which proved that the hardware system can satisfy the quick response requirement of angle measure. Solution time of fuzzy-PI deviation correction method was 2 134 &mu;s, less than the other tow methods because the hardware system with fuzzy-PI deviation correction method had a good real-time performance and was suitable for fast calculation measure. In addition, in long static measurement, the proposed method did not generate static drift or divergence and in dynamic measurement, roll angle and pitch angle tracking maximum error was 1.969&deg; and 3.581&deg; with measurement accuracy reaching 1&deg;, which results were closed to DMP solver within MPU6050. The dynamic measure experiment demonstrated that dynamic correcting deviation among multi-sensor in the fuzzy-PI deviation correction method can effectively modify the deviation among sensors, fast and accurately measure vehicle movement. Our study showed that the multi-sensor hardware system based on fuzzy-PI deviation correction method with characteristics of higher solution frequency, higher accuracy, lower cost, can implement for detecting attitude angles of wide range types of vehicles.
Number of references:15
Main heading:Fuzzy filters
Controlled terms:Accelerometers - Aircraft - Aircraft control - Aircraft detection - Algorithms - Electromagnetic wave attenuation - Experiments - Fuzzy rules - Gyroscopes - Hardware  - Integration - Remote sensing - Sensors - Water craft
Uncontrolled terms:Complementary filters - Coordinate conversion - Deviation corrections - Horizontal acceleration - Multi-sensor information fusion - Quaternion - Remote sensing technology - Satellite remote sensing
Classification code:605 Small Tools and Hardware - 652 Aircraft and Avionics - 652.1 Aircraft, General - 674.1 Small Marine Craft - 711 Electromagnetic Waves - 716.2 Radar Systems and Equipment - 723 Computer Software, Data Handling and Applications - 731.1 Control Systems - 801 Chemistry - 901.3 Engineering Research - 921.2 Calculus - 943.1 Mechanical Instruments
DOI:10.3969/j.issn.1002-6819.2014.20.003
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 26>

Accession number:20145100353417
Title:Monitoring and classification of wheat take-all in field based on imaging spectrometer
Authors:Qiao, Hongbo (1); Shi, Yue (1); Si, Haiping (1); Wu, Xu (1); Guo, Wei (1); Shi, Lei (1); Ma, Xinming (1); Zhou, Yilin (2)
Author affiliation:(1) Collaborative Innovation Center of Henan Grain Crops / College of Information and Management Science, Henan Agriculture University, Zhengzhou , China; (2) State Key Laboratory for Biology of Plant Diseases and Insect Pests, Beijing, China
Corresponding author:Qiao, Hongbo
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:172-178
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Wheat take-all is a quarantine disease, which will lead to a disaster in wheat production without timely monitoring and management. Remote sensing technique, especially the field-based imaging spectrum technique, can achieve real-time monitoring of the disease development. For rapid extraction of take-all disease information, we try to monitor wheat take-all disease using imaging spectrometer. The experiment was carried out in Baisha village, Yuanyang County of China. We designed test of three concentration gradients and repeated three times, the experimental field was 30 m². The wheat take-all white head rate was surveyed two weeks before harvest. The wheat's canopy spectrum was collected by two kinds of spectrometer, ASD Handheld non-imaging spectrometer (ASD Handheld, ASD Inc.) and Headwall imaging spectrometer (HyperSpec&reg; VNIR, Headwall Photonics, Inc.). All data were collected between 10:00 to 13:00 in sunny days. In this study, based on gray association analysis (GAA) and support vector machine (SVM) classifier, a spectral feature extraction and classification method was proposed to separate the spectral features of the different take-all levels from spectral images. The field-based spectral images were acquired by Headwall imaging sensor. Meanwhile, the spectral data about different white head rate were collected by ASD HandHeld non-imaging sensor. Because of better accuracy and resolution, ASD spectral data had a better capacity to express the spectral features of take-all levels. These spectral features were extracted using kernel principle component analysis (K-PCA). Characteristic bands of the first four of principal component was mainly green band, red band and near infrared band, indicated in the spectrum curve, peak and valley phenomenon was the main distinguishing feature of white head rate and take-all disease grade. Then Jeffries-Matusita distances between feature bands were calculated, if Jeffries-Matusita distances between feature bands were greater than 1.8, the selected characteristic bands can distinguish different damage degree of wheat take-all disease. The spectral separability of take-all levels was tested and assessed by grey association analysis. Based on these significant features, some of Headwall imaging spectral data with different take-all levels were selected as the training data for the field-based spectral images. Through the SVM classifier based on RBF kernel function, a hyperspectral classification image of take-all was calculated. Results showed that the wheat take-all widely existed in the experimental zone, but its distribution had own specific characteristic with different disease levels. The slight disease wheat and the heavy disease wheat were mixture in the experimental zone. The distribution characteristics of serious take-all wheat disease (white head rate greater than 60%) were intensive and block. Slight wheat disease (white head rate between 10%-30%) were widely distributed in the middle of heavy wheat disease(white ear rate between 30%-60%), the proportion of slight wheat disease and heavy heat disease was 29.53% and 26.06%, respectively, very serious wheat take-all disease (white head rate between 60%-90%) and death of wheat disease showed regional distribution in the image, accounted for 10.73% and 19.91%.The overall accuracy of the classification was greater than 94% (Kappa&gt;0.8). To further validate the classification accuracy, field experiment survey data was compared with the spectral classification, misclassification existed mainly in white head rate 30%~40%.These results proves the field-based imaging spectrum has the capacity to achieve the real-time monitoring and classification of wheat take-all condition, and to support the guidance on wheat production.
Number of references:34
Main heading:Image classification
Controlled terms:Classification (of information) - Diseases - Experiments - Extraction - Feature extraction - Image processing - Infrared devices - Principal component analysis - Remote sensing - Spectrometers  - Spectroscopy - Spectrum analysis - Support vector machines - Surveys
Uncontrolled terms:Association analysis - Distribution characteristics - Hyper-spectral classification - Kernel principle component analysis - Remote sensing monitoring - Spectral feature extraction - Spectral images - Take-all
Classification code:405.3 Surveying - 461.7 Health Care - 716 Telecommunication; Radar, Radio and Television - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 731.1 Control Systems - 741 Light, Optics and Optical Devices - 741.3 Optical Devices and Systems - 801 Chemistry - 802.3 Chemical Operations - 901.3 Engineering Research - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2014.20.021
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 27>

Accession number:20145100353425
Title:Heat transfer characteristics of SiO<inf>2</inf> nanofluid flow inside solar-collector vacuum tubes
Authors:Zhao, Congying (1); Yan, Suying (1); Tian, Rui (1); Shi, Zhiguo (1); Zhong, Weihao (1)
Author affiliation:(1) School of Energy and Power Engineering, Inner Mongolia University of Technology, Hohhot, China; (2) Key Laboratory of Wind and Solar Power Energy Utilization Technology Ministry of Education and Inner Mongolia Construction, Hohhot , China
Corresponding author:Yan, Suying
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:236-243
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Nanofluid is an innovative heat transfer fluid with superior potential for developing the heat transfer performance of fluids. Recent developments in nanotechnology showed that the nanofluid was an efficient working fluid and coolant in the solar thermal application. In this paper, the heat transfer characteristics of SiO<inf>2</inf>-water nanofluids were investigated both numerically and experimentally. Stable SiO<inf>2</inf>-water nanofluids were produced by the M-110P Microfluidizer Processor using two-step method in the experiment. The suspension stability was characterized through particle size analysis; Meanwhile, the thermal conductivity was measured by the Hot Disk Thermal Constant Analyzer, the results showed that the thermal conductivity was increased with the increase of mass fraction and temperature. The thermal conductivity of nanofluid with mass fraction 5% placed for 20 d was the least compared with other fresh nanofluids (mass fraction 5%, 3%, 1%) at the same temperatures. What's more, the transmittance of SiO<inf>2</inf>-water nanofluids with the mass fraction from 1% to 5% were tested and analyzed by the spectrophotometer. The results indicated that the transmittance of SiO<inf>2</inf>-water nanofluids was increase as the mass fraction decrease. Also, the results showed that the transmittance of SiO<inf>2</inf>-water nanofluid changed with the retention time. The transmittance of 5% nanofluid was 0.76, which is 0.09 higher than that of the nanofluid (5%) placed for 20 days at the same wavelength. Mainly for the heat transfer characteristics of SiO<inf>2</inf>-water nanofluid flowing inside the collector tube, the temperature field and velocity field distribution of distilled water and nanofluid were simulated by the finite element software ANSYS. The velocity of 5%, 3% and 1% nanofluids were 1.25, 1.14 and 1.02 mm/s after heated for 60 min, respectively. The velocity of 5% nanofluid was 1.61 mm/s after heated for 142 min, which was 0.86 mm/s faster than that of distilled water at the same position. For the experimental study, the distilled water and nanofluid with 5% SiO<inf>2</inf> were chosen as working fluid of solar-collector vacuum tubes in the insolation experiment, respectively. The solar-collector consisted of 80 mm diameter circular tube with a length of 470 mm and was tested in Hohhot, Inner Mongolia, which was divided into richer region of the solar energy resources in China. The experiment was carried out to test temperature of working fluid by thermocouples at the same positions in the solar collectors. The experimental errors of thermocouples were less than &plusmn;0.2 after demarcated and the measurement accuracy of the data logger was &plusmn;0.3%, which made assurance to the high accuracy of the experiment. Experimental results showed that the heat transfer characteristics of SiO<inf>2</inf>-water nanofluid was higher than distilled water's and increased as its mass fraction increasing. The temperature of 5% SiO<inf>2</inf>-water nanofluid was increased by 3.0% at 8:30a.m, while it increased by 6.6% at 10:15a.m when compared with the distilled water at the same position (upper part). The results of simulation and experiments were agreed on the whole. Also, the influence of the retention time of nanofluids to its heat transfer characteristics was analyzed in the experiment. Results showed that, the longer time of nanofluid was placed, the more obvious nanofluid reunited, the lower of its heat transfer characteristics become. This work provided a reference for the nanofluids applied in the solar thermal and photovoltaic cooling application.
Number of references:21
Main heading:Nanofluidics
Controlled terms:Electron tubes - Energy resources - Experiments - Finite element method - Fluids - Heat transfer - Measurement errors - Particle size - Particle size analysis - Solar collectors  - Solar energy - Solar heating - Solar power generation - Suspensions (fluids) - Thermal conductivity of liquids - Thermocouples - Tubes (components) - Velocity
Uncontrolled terms:Finite element software - Heat transfer characteristics - Heat transfer performance - Innovative heat transfer - Measurement accuracy - Nanofluids - Solar thermal applications - Thermal constant
Classification code:525.1 Energy Resources and Renewable Energy Issues - 615.2 Solar Power - 616.1 Heat Exchange Equipment and Components - 641.2 Heat Transfer - 643.1 Space Heating - 702.3 Solar Cells - 714.1 Electron Tubes - 761 Nanotechnology - 804 Chemical Products Generally - 901.3 Engineering Research - 921.6 Numerical Methods - 922 Statistical Methods - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids - 933 Solid State Physics - 944.5 Temperature Measuring Instruments - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.20.029
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 28>

Accession number:20145100353401
Title:Measurement comparison and fitted distribution equation of droplet size for agricultural nozzles
Authors:Wang, Shuangshuang (1); He, Xiongkui (2); Song, Jianli (2); Zhang, Luda (2); Dorr, Gary J. (3); Herbst, Andreas (4)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing, China; (2) College of Science, China Agricultural University, Beijing , China; (3) The University of Queensland, School Agricultural and Food Sciences, Gatton; QLD, Australia; (4) Institute for Application Techniques in Plant Protection, JKI, Messeweg 11/12, Braunschweig, Germany
Corresponding author:He, Xiongkui
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:34-42
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to investigate the function expression of droplet size distribution in the spray sheet for agricultural nozzles to improve the pesticide efficacy, some common nozzle types were tested in this study. At present many methods and equipment were used for measuring droplet size. Droplet size is a main parameter influencing the deposition rate and distribution uniformity of pesticide on the target. However, different test results may be caused by different methods or equipment. For selecting a suitable analyzer to test droplet size distribution, three common droplet size analyzers were applied to measure droplet sizes of ST110-03 and ST110-02 nozzles which were standard flat-fan nozzles manufactured by Lechler GmbH. The three analyzers were Particle/Droplet image analysis system, Sympatec HELOS Vario particle size analyzer and Spraytec laser diffraction system and were referred to as PDIA, Sympatec and Spraytec, respectively. Their respective locations were the Institute for Application Techniques in Plant Protection of JKI (Julius K&uuml;hn-Institut), Germany, the Centre for Pesticide Application and Safety of the University of Queensland, Australia, and the Centre for Chemicals Application Technology of China Agricultural University, China. For all the sprays in this study, tap water was sprayed at an operating pressure of 0.3 MPa, and each apparatus was operated complying with its corresponding experimental procedure. For each nozzle type, 3 nozzles were tested with three replications. Results showed that absolute results differed between different tests depending on measuring protocol and type of measuring apparatus, but the nozzle classifications were the same, comparing the results with limits of BCPC nozzle classification obtained by PDIA in JKI. Spraytec was more accessible to authors than other analyzers; therefore, it was selected to study the distribution of droplet size. The volume median diameters (VMDs) of air-induction compact nozzles (IDK), standard flat-fan nozzles (ST) and hollow-cone nozzles (TR), with the orifice sizes of 02 and 03 for each type, were measured at different positions in the spray sheet. The nozzles were all produced by Lechler GmbH in Germany. It was found that the VMD distributions were symmetric for all tested nozzles and the axis of symmetry was the centerline of spray sheet. The VMDs of IDK nozzles were significantly larger than other two types'. The coefficient of variation (CV) of droplet sizes, which were tested at different spray heights but the same horizontal position, indicated that the VMDs of IDK nozzles varied with spray height obviously. Meanwhile, at a fixed spray height, the VMD distribution of IDK along the horizontal direction appeared to be W-shaped; the distributions of ST and TR were parabolas. The parabola opening of ST was larger than that of TR. The tested VMD was then fitted with program code using Matlab software based on least square method. In the fitted VMD distribution equation, independent variables were spray height and horizontal position and dependent variable was VMD. The significant relationship between distribution position and VMD was found, the significance threshold &alpha; was set at 0.05. Results also showed that the F-statistic calculated from the data of each nozzle was greater than the critical value of the F-distribution for the desired false-rejection probability of 0.05. The coefficient of determination was greater than 0.8 for all fitted equations. All of these pointed that the obtained equations could describe the droplet size distribution correctly and predicate the size at any position in the spray sheet with precision. The fitted function research involved in this paper will provide the valuable basis to study the VMD distribution of overlapped spray sheet for boom sprayer; the study will improve the uniformity of deposition rate and biological efficacy. Meanwhile, the fine droplet zone in the spray sheet is the target of drift control. Therefore, the VMD distribution is also conducive to the development of novel anti-drift sprayer to reduce the risk of pesticide.
Number of references:34
Main heading:Spray nozzles
Controlled terms:Agriculture - Atomization - Deposition - Deposition rates - Drop formation - Least squares approximations - MATLAB - Nozzles - Particle size - Particle size analysis  - Pesticides - Size distribution - Software testing
Uncontrolled terms:Application technologies - Coefficient of determination - Coefficient of variation - Droplet size distributions - Least square methods - Measurement comparison - Regression - University of Queensland
Classification code:617 Turbines and Steam Turbines - 631.1 Fluid Flow, General - 723.5 Computer Applications - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.6 Numerical Methods - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.20.005
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 29>

Accession number:20145100353416
Title:Monitoring method of micro-grid based on DPWS network middleware and Petri nets
Authors:Zhang, Libin (1); He, Yuzhu (1); Xu, Fang (1); Tan, Dapeng (1)
Author affiliation:(1) Key Laboratory of Special Purpose Equipment and Advanced Processing Technology, Zhejiang University of Technology/College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, China; (2) School of New Energy Science and Engineering, Xinyu University, Xinyu, China
Corresponding author:Xu, Fang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:163-171
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Current micro-grid systems have problems of poor cooperation abilities and feeble dynamic configuration supports for network structure, and don't cope well with the issues of coexistence caused by the continuous dynamic systems (CDS) and discrete event dynamic systems (DEDS). In order to resolve the matter, a novel micro-grid monitoring network architecture based on the device profile for web service (DPWS) and interpreted Petri nets (IPN) was put forward to analyze the multiple states and the transform relations of different distributed micro sources during the running process of the micro-grid system. Referring to the function requirements and working characteristics of a micro-grid monitoring network system, an intelligent network architecture model for the mixed actions of distributed micro sources was set up. Based on the above model, according to the self-discovering/networking mechanism of DPWS for the target device, the dynamical configuration and automatic discovery for micro-grid system would be realized to improve the adaptive performance and intelligent level of micro-grid system. By the DPWS event subscribing interfaces and dynamical service methods, the distributed real-time monitoring was reached for the distributed micro sources in the micro-grid system. Based on the above research, the DPWS customized encryption mechanism and data transmission methods were combined to address the information security and working stability issues of the micro-grid system, and the simulated models for the monitoring system of the micro-grid were built up by using the IPN. Therefore, the automatic and intelligent level of the device terminal of the micro system were improved, and the running stableness and safety performance were enhanced. Based on the proposed methods, the corresponding numerical experiments were accomplished, and the results showed that the model could describe the concurrency and hybrid phenomena of a micro-grid system. The proposed control strategies can provide adequate self-adapting monitoring services (automatic networking, dynamical configuration, automatic delete, inter-help service, intelligent linking, on-line remote access, large quantity stream data transmission, and automatic data storage) for the micro-grid system, meet the requirements of the micro-grid operations, and provide the technical references to guarantee safe and stable system running. As indicated in the paper, the modeling and analysis for the micro-grid system had high technical difficulties, and the paper performed the corresponding attempts for the area. The research results of the paper provides theoretical references and technical supports for the researcher and engineering in the regions of intelligent network, smart grid, condition based monitoring, and real-time data transmission. Further studies should be carried out on the facets of architecture model optimization, real-time data transmission protocols, IPN model improvement, and industrial field experiments.
Number of references:20
Main heading:Monitoring
Controlled terms:Computer simulation - Data communication systems - Data transfer - Digital storage - Dynamics - Electric power distribution - Experiments - Intelligent networks - Middleware - Models  - Network architecture - Numerical methods - Petri nets - Security of data - Social networking (online) - Web services
Uncontrolled terms:Condition-based monitoring - Continuous dynamic systems - Device profile - Discrete event dynamic systems - Micro grid - Real time data transmission - Real-time data transmission protocols - Technical difficulties
Classification code:706.1.2 Electric Power Distribution - 716 Telecommunication; Radar, Radio and Television - 717 Optical Communication - 718 Telephone Systems and Related Technologies; Line Communications - 722.1 Data Storage, Equipment and Techniques - 723 Computer Software, Data Handling and Applications - 901.3 Engineering Research - 902.1 Engineering Graphics - 921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory - 921.6 Numerical Methods - 931.1 Mechanics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.20.020
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 30>

Accession number:20145100353400
Title:Optimal design and test of electromechanical control system of automatic feeder for nursing sow
Authors:Xiong, Benhai (1); Yang, Liang (1); Cao, Pei (2); Pan, Xiaohua (1); Wang, Mingli (2)
Author affiliation:(1) State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing , China; (2) Henan NanShang Sci. and Tech. Co., LTD, Zhengzhou , China
Corresponding author:Xiong, Benhai
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:28-33
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the rapid development of large-scale and intensive breeding pig farms in China, the demand for digital intelligent feeding equipment has been increased. In order to realize precise feeding, and to meet the requirements of small intake with more times and dynamically adjusting feed intake based on lactation days, one automatic electro-mechanical feeding control systems of lactating sows was designed in this study. In the system, the electro-mechanical systems, wireless network technology, mobile Structured Query Language Lite network database, and electronic data interchange were integrated with feed intake prediction models of lactating sow nutrient requirements. This intelligent feeding system included main parts of feed supply line, buffer feed bin, feed level control tube, feed level control hand shank, feed level viewing port, feeding control line tube, screw conveyer, center control integrated box, laying-off trigger, feed containing groove and feed flowing tube. The system integrated predetermined ration intake prediction models of nursing sows into microprocessor memory, and combined wiper motor's precise electronic control technology to realize the precise control of diet feeding. Results showed that the total residual of daily feed for each sow was less than 50 g. In the system, the level indicator and artificial observation hole in storage silo were used to keep feed fresh and to reduce arch, and the advised feed storage was 10 times as much as the predicted daily feed intake for sows in early lactation; Besides, the predefined dynamic feeding system could meet the requirement of feed intake by the 28 days lactating sows, and the feed intake curve was converged to the logarithm curve. A 28-d feeding experiment was conducted with a total of 531 piglets divided into 1 test group and 3 control groups. Each group had farrowing parities of 30, 36, 12, and 20 respectively. The pigelets were fed with the pre-set feed amount calculated by the feed intake prediction models in system for 4 times per day with ratio in feed of 30%, 25%, 25% and 20%, The results demonstrated that the piglets in test group had more feed intake (P&lt;0.05) and higher average daily gain (P&lt;0.01) compared with other 3 control groups. Taking the convenience of installation, trough clearing and feed ingestion into consideration, the install height of the laying-off trigger was suggested to be about 10 cm beyond the bottom of feed trough. This height is very convenient to install the feeding equipment and to connect with the related software systems. In conclusion, the designed electronic automatic feeding system of lactation sows adopts electro-mechanical integrate system and can work without sensors and electronic identification system such as Radio Frequency Identification Device. It is easy to operate and maintain, and feasible for use in common breeding sow farms. Additonally, it takes lower cost compared with expensive import devices as USA Osborne, France Elistar and the Netherlands Velos sow feeding devices, and thus is suitable for small and medium sow breeding farms. However, more studies are needed to verify the sows' feed intake characteristic and weaning piglets' performances, and to evaluate the performance of the proposed intelligent feeding system based on indicators such as estrus returning rate and survival rate of commercial pigs in life cycle of pigs.
Number of references:17
Main heading:Search engines
Controlled terms:Control systems - Digital storage - Electronic data interchange - Feeding - Forecasting - Intelligent systems - Level control - Life cycle - Mammals - Materials handling equipment  - Mathematical models - Nursing - Physiology - Query languages - Query processing - Radio frequency identification (RFID) - Tubes (components)
Uncontrolled terms:Automatic feeding systems - Electro-mechanical control - Electromechanical systems - Lactation sow - Laying-off trigger - Radio frequency identification devices - Storage silos - Wireless network technologies
Classification code:461.7 Health Care - 461.9 Biology - 616.1 Heat Exchange Equipment and Components - 691.1 Materials Handling Equipment - 691.2 Materials Handling Methods - 722.1 Data Storage, Equipment and Techniques - 723 Computer Software, Data Handling and Applications - 731.1 Control Systems - 731.3 Specific Variables Control - 913.1 Production Engineering - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2014.20.004
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 31>

Accession number:20145100353419
Title:Inversion method of flora growth parameters based on machine vision
Authors:Sun, Guoxiang (1); Wang, Xiaochan (1); Yan, Tingting (1); Li, Xue (1); Chen, Man (1); Shi, Yinyan (1); Chen, Jingbo (1)
Author affiliation:(1) College of Engineering, Nanjing Agricultural University, Nanjing, China; (2) Jiangsu Province Engineering Lab for Modern Facility Agriculture Technology and Equipment, Nanjing, China
Corresponding author:Wang, Xiaochan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:187-195
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to perform online and nondestructive measurements of the parameters of flora, the use of machine vision technology was investigated. This technology was used to capture the image of a flora canopy, and then three segmentation algorithms: Excess Green (ExG) minus Excess Red (ExR), ExG, and normalized difference indices (NDI) were used to extract the canopy area of the flora. The ExG and NDI used an Otsu threshold value to obtain a binary image, and the ExG-ExR used a fixed threshold value to obtain a binary image. Flora canopy characteristic parameters (covering ratio, canopy length, and canopy width) were extracted based on the projection profile of the canopy leaves extracted by the flora canopy segmentation methods. These were combined with the parameters of the flora obtained by artificial measurement: stem height, stem diameter, leaf number, fruit number, and LAI (fitting value), to form five types of inversion models for the five growth parameters of the flora. The inversion models were based on the covering ratio, canopy width, and canopy length, and a regression equation established by three parameters of the flora and an average inversion model were established. The results showed that the contact ratio and recognition rate of extraction of the flora canopy region, using the segmentation method ExG-ExR, were more than 99.5% and 98.2%, respectively. Furthermore, identification of the flora canopy was accurate, and there were very few mistakenly identified areas. No matter when the image was captured, the recognition performance of the flora canopy image was stable, and the performance was superior to the methods ExG Otsu and NDI Otsu. The contact ratio of the ExG Otsu segmentation method ranged from 72.7% to 93.5% and recognition rate was 71.1%-90.2%, and showed a small amount of leakage and error used to partition the flora canopy figures. The contact ratio of the NDI Otsu segmentation method ranged from 99.9% to 100%, however, the scope of the recognition rate was 13.1%-89.2%, and showed a high incidence of false recognition and unstable performance. Inversion models were validated using 120 new images. The inversion results showed that the regression coefficient between the inversion value and the measured value was greater than 0.958 when using the inversion model of the flora canopy covering ratio. The performance of the flora canopy covering ratio was superior to the inversion models of canopy width and canopy length. The inversion model using the regression equation and the average model were the only two parameters that were better than the inversion model of the covering ratio. Between the inversion values of stem height, stem diameter, leaf number, fruit number, LAI, and the measured values of each, the regression coefficient were 0.979, 0.976, 0.979, 0.965, and 0.973, respectively, and the SE were 10.55 cm, 1.37, 0.213 mm, 0.672, and 0.055, respectively. The inversion method, based on machine vision technology, can achieve online and nondestructive measurements of the parameters of flora, which can provide significant advances in controlling the greenhouse environment and precise fertigation.
Number of references:23
Main heading:Image segmentation
Controlled terms:Algorithms - Binary images - Computer vision - Forestry - Fruits - Image processing - Mathematical models - Nondestructive examination - Parameter estimation - Regression analysis  - Social networking (online)
Uncontrolled terms:Flora - Growth parameters - Inversion - Machine vision technologies - Non-destructive measurement - Normalized difference indices - Regression coefficient - Segmentation algorithms
Classification code:421 Strength of Building Materials; Mechanical Properties - 723 Computer Software, Data Handling and Applications - 731.1 Control Systems - 731.6 Robot Applications - 821.0 Woodlands and Forestry - 821.4 Agricultural Products - 921 Mathematics - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2014.20.023
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 32>

Accession number:20145100353434
Title:Preserved effect of nano-Fe³/TiO<inf>2</inf> modified PVA-based composite preservation coating for eggs
Authors:Long, Men (1); Ma, Lei (1); Song, Ye (1); Gu, Fenglan (1); Huang, Mingming (1); Zhang, Jianhao (1)
Author affiliation:(1) Food Safety and Nutrition Collaborative Innovation Center, College of Food Science and Technology, Nanjing Agricultural University, Nanjing , China; (2) College of Biological and Food Engineering, Chuzhou College, Chuzhou , China
Corresponding author:Zhang, Jianhao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:313-324
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Eggs are highly nutritional food, and contain a variety of amino acids, proteins, minerals, lecithin, sterols, and other essential nutrients that can be fully absorbed by human body. However, the quality of unsterilized and unwashed eggs will deteriorate rapidly during storage, including such conditions as water evaporation, weight loss, and yolk coefficient decrease. In such cases, cleaned and sterilized eggs can effectively suppress harmful pathogens and extend the shelf life of egg products. But cleansing and sterilization could possibly destroy the outer shell membrane of eggs, which causes the eggs to be vulnerable to microbial contamination, as the outer shell membrane has been destroyed. The outer shell membrane can prevent microbial invasion of eggs, so the destruction of the outer shell membrane makes water evaporate through the pores of the shell membrane, and finally causes the spoilage of fresh eggs. Therefore, one of the most effective ways of keeping eggs fresh is to coat eggs with an antimicrobial film. In this paper, polyvinyl alcohol/shellac/ nano-Fe³/TiO<inf>2</inf> composite film prepared by the author is used to preserve eggs by fully covering them. The composite film materials include nano-Fe³/TiO<inf>2</inf> which is fabricated by blending nano-Fe³ with nano-TiO<inf>2</inf> in a solution and then calcining them at 400 for 3 hours, PVA (polyvinyl alcohol), and shellac. For antimicrobial film preparation, the first step is preparing the coating film solution by slowly dissolving 5 g/mL PVA in distilled water while stirring and then heating the coating film solutions up to 85&deg;C. The second step is incorporating nano-Fe³/TiO<inf>2</inf>, which is dissolved in anhydrous ethanol, into the coating film solution and then shocking composite film solutions with ultrasonic at 65 W/L for 15 min in an ultrasonic bath. The third step is incorporating succinylated monoglycerides and shellac, which are dissolved in anhydrous ethanol into PVA/nano-Fe³/TiO<inf>2</inf> composite film solutions, while stirring and then cooling the solution to 60&deg;C. After preparing the composite film solutions, fresh eggs were used as experimental material and were cleaned and disinfected, and then were coated with composite film. Sensory quality, weight loss, Haugh units (HU), egg yolk coefficient, chromatic aberration, pH, and total number of colonies of different groups were measured, and quality changes of different treatment groups were compared during their storage period. The result shows that quality indicators of fresh eggs in different groups significantly changed (P&lt;0.05). The total number of colonies of fresh eggs during the storage period had a significant upward trend. The shelf life of fresh and cleaned eggs was 20-30 d depend on the change of quality indicators. The shelf life of fresh eggs coated by PVA single film was up to 50-60 d, and the shelf life of fresh eggs coated by PVA/shellac/nano-Fe³/TiO<inf>2</inf> composite film was up to 70-80 d. In addition, the preservation properties of fresh eggs coated by PVA/shellac/nano-Fe³/TiO<inf>2</inf> composite film were significantly better than fresh eggs coated by PVA single film, and PVA/shellac/nano-Fe³/TiO<inf>2</inf> composite film significantly reduced the rate of change of weight loss, Haugh unit, and yolk coefficient of fresh eggs during storage period (P&lt;0.05) compared to other groups. Therefore, PVA/shellac/nano-Fe³/TiO<inf>2</inf> composite film achieved the purpose of extending the shelf life of eggs and it can be applied to package fresh eggs. This paper provides reference for the application of nano-modified composite film materials in the preservation of fresh eggs.
Number of references:48
Main heading:Nanocomposite films
Controlled terms:Aberrations - Amino acids - Blending - Coatings - Composite materials - Dissolution - Energy storage - Ethanol - Film preparation - Membranes  - Microorganisms - Polyvinyl alcohols - Quality control - Sensory perception - Shells (structures) - Storage (materials)
Uncontrolled terms:Antimicrobial films - Chromatic aberration - Different treatments - Experimental materials - Microbial contamination - Nano-Fe - Shellac - Storage periods
Classification code:408.2 Structural Members and Shapes - 461 Bioengineering and Biology - 523 Liquid Fuels - 539 Metals Corrosion and Protection; Metal Plating - 694.4 Storage - 702 Electric Batteries and Fuel Cells - 712.1 Semiconducting Materials - 741 Light, Optics and Optical Devices - 802.3 Chemical Operations - 815.1.1 Organic Polymers - 913.3 Quality Assurance and Control - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.20.038
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 33>

Accession number:20145100353423
Title:Planting structure optimization based on agricultural non-point source pollution control in Three Gorges Reservoir Region
Authors:Xiao, Xincheng (1); Xie, Deti (1); He, Binghui (1); Wei, Chaofu (1); Ni, Jiupai (1)
Author affiliation:(1) College of Environment Resources, Southwest University, Chongqing, China; (2) School of Economics and Management, Yichun University, Yichun , China
Corresponding author:Xie, Deti
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:219-227
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Agricultural non-point source pollution has gradually become a major pollution source of lake eutrophication and deterioration of water quality in recent years. The Three Gorges Reservoir Region is both an important sensitive eco-economy area and a typical poverty-stricken mountain area. However, its unique geographical location, its irrational agricultural structure and its increasing serious agricultural non-point source pollution problems challenge the environment in this region. Hence, it is a necessity to take controlling agricultural non-point source pollution from the source as one of the most effective approaches. In current research, agricultural non-point source pollution control excessively depends on engineering and technology. Anyhow, the roles of agricultural planting structure adjustment and agricultural cleaner production which can reduce non-point source pollution should not be ignored. Promoting the adjustment of planting structure, reducing the use of chemical fertilizers and pesticides, and adopting agricultural cleaner production technologies not only help improve the land production capacity and agricultural products quality, but also effectively reduce the agricultural non-point source pollution. By these important measures for energy saving and emission reduction can be realized in Three Gorges Reservoir Region. Based on the dual goals of the optimal agricultural economic benefits and non-point source pollution emission reduction, the linear programming model was used to optimize the planting structure and clean agricultural production in the Three Gorges Reservoir Region. The optimization results showed that the optimal paths to maximize the crop net income were as follows: The land area for grain production should cover 119.16&times;10⁴ hm² but cleaner production area of rice-wheat, corn, soybean and tuber crops needs 31.91&times;10⁴, 18.69&times;10⁴, 6.79&times;10⁴ and 19.55&times;10⁴ hm²; the land area for vegetables planting should be 33.25&times;10⁴ hm² and its cleaner production area was 18.26&times;10⁴ hm²; the total land area for tobacco, fruits and tea planting should be 17.05&times;10⁴ hm² and the cleaner production area was 2.65&times;10⁴, 10.28&times;10⁴ and 0.95&times;10⁴ hm². In the premise of stable grain production, the conventionally grown grain, corn and soybean planting area can be gradually reduced. Otherwise, the planting areas of tobacco, vegetables, fruits and tea can be appropriately increased. In the process of crops production, according to the present ecological agriculture construction, the clean production can be vigorously promoted. The soil testing and formulated fertilization areas for food production in rice, wheat, oil crops, corn and soybean must be expanded. The organic vegetable planting can be increased positively. If the construction of the vegetable greenhouse is strengthened, the farmers' household farming pattern will be affected, regulated, or transferred. Therefore, the losses of nitrogen and phosphorus in agricultural non-point source runoff can be decreased. The local government should encourage farmers to develop the sustainable agriculture and make them realize that if the agriculture nonpoint pollution can be mitigated, the greatest social welfare will be got in the Three Gorges Reservoir Region, which are the bilateral-won benefits. By this means, both the non-point source pollution can be controlled and the sustainable development of agricultural economy can be realized. Therefore, the optimization of various crops is important to control agricultural non-point source pollution. Space layout has played a decisive role in the process of the entire agricultural land system optimization. The economic and environmental comparative advantage of agricultural land can be achieved. The goal of total emission control of agricultural non-point can be achieved by reasonable structure adjustment and regional distribution of planting industry. Further research will be required to achieve the targets of controlling the total pollution emission.
Number of references:30
Main heading:Pollution control
Controlled terms:Agricultural products - Agricultural runoff - Crops - Economic and social effects - Economics - Emission control - Energy conservation - Eutrophication - Fertilizers - Fruits  - Grain (agricultural product) - Lake pollution - Linear programming - Oils and fats - Pollution induced corrosion - Shape optimization - Soil testing - Soybean oil - Structural optimization - Sustainable development  - Tobacco - Vegetables - Water quality
Uncontrolled terms:Agricultural non-point source pollutions - Agricultural productions - Energy saving and emission reductions - Engineering and technology - Linear programming models - Non-point source pollution - Sustainable agriculture - Three Gorges Reservoir region
Classification code:451.2 Air Pollution Control - 453 Water Pollution - 454.2 Environmental Impact and Protection - 483.1 Soils and Soil Mechanics - 525.2 Energy Conservation - 804 Chemical Products Generally - 804.1 Organic Compounds - 821.4 Agricultural Products - 821.5 Agricultural Wastes - 911.2 Industrial Economics - 921.5 Optimization Techniques - 971 Social Sciences
DOI:10.3969/j.issn.1002-6819.2014.20.027
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 34>

Accession number:20145100353409
Title:Development and evaluation of pedo-transfer functions of soil water characteristic curves in Horqin sandy land
Authors:Yao, Jiaozhuan (1); Liu, Tingxi (1); Wang, Tianshuai (1); Tong, Xin (1)
Author affiliation:(1) Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot, China
Corresponding author:Liu, Tingxi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:98-108
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In the regional basin water system or ground-water soil-plant-atmosphere continuum system, soil moisture migration simulation and water-heat-solute coupled modeling often require values of soil hydraulic properties such as soil water retention and permeability. In order to quickly and easily obtain accurate soil water characteristic curves (SWCC), the typical dune-meadow areas in Horqin sandy land was selected as the study area. The pedo-transfer functions (PTFs) between the soil water characteristic curves and the basic soil properties was established by the nonlinear programming method in term of bulk density, soil particle size distribution, soil organic matter (SOM), electricity conductivity and pH. Nonlinear optimal programming method, which is based on the minimum absolute deviation as the objective function, was used for minimizing residuals, especially diminishing the effect of extremes. PTFs at the soil depth of 20 cm were evaluated based on parameters such as residual mean square error, and correlation coefficient between the fitted and predicted values. Results showed that: 1) Soil texture in the Horqin was mainly sand, partially sandy loam or loamy sand, most of the volume content of the sand particle was higher than 83%, even up to 100%; Soil water constant was correlated with sand content and bulk density, but weakly associated with clay and silt content. SWCC in different landscapes and land use was different under the same suction, and the soil water holding capacity increased following the order of sand dune, semi-fixed dune, fixed dune, farmland and meadow; The soil water capacity decreased in an order of sand dunes, semi-fixed dune, fixed dune, meadow, and farmland. With the increase of suction, soil moisture changed in a stage from rapid decline and slow decline to stable stage; Specific water capacity of sand dune, semi-fixed dune, fixed dune was reduced after the first growth with the increase of soil suction; However, specific water capacity of farmland and meadow was gradually decreased with the increase of soil suction; 2) Bulk density and sand content were the main variables that could be used for predicting the model parameters of the SWCC; The accuracy of the PTFs could be improved when the model included the soil physical and chemical properties; However, soil organic matter, pH value and electricity conductivity had a more important impact on logarithm of water retention curve parameters than soil moisture in this region; and 3) Most of the SWCC had high prediction accuracy, and the shapes of all the predict curves of SWCC were similar to that of the measured curves; The sampling sites with low precision were mostly meadow and farmland since plant roots were extremely developed, microbial activity was frequent, and soil structure was relatively loose, thereby causing the soil water content higher than sand dunes under the same suction. In addition, the number of the sampling sites of farmland and meadow was too small, which may lower the weight of such land when simulation analysis of the parameters was conducted. Through verifying and evaluating the accuracy of the PTFs, it was found that the PTFs had enough accuracy to simulate the soil moisture migration in this region. This function was preferable for estimating the SWCC. The results can provide important information for studying the soil moisture migration and soil water-heat-salt transports in the arid and semi-arid areas like Horqin sandy land.
Number of references:24
Main heading:Soil moisture
Controlled terms:Arid regions - Biogeochemistry - Biological materials - Chemical properties - Farms - Forecasting - Function evaluation - Groundwater - Importance sampling - Land use  - Landforms - Mean square error - Nonlinear programming - Organic compounds - Particle size - Particle size analysis - pH - Physical properties - Plants (botany) - Sand  - Soils - Transfer functions - Water content
Uncontrolled terms:Arid and semi-arid areas - Horqin sandy lands - Nonlinear programming methods - Pedo-transfer functions - Soil hydraulic properties - Soil physical and chemical properties - Soil-water characteristic curve - Water characteristics
Classification code:403 Urban and Regional Planning and Development - 423 Non Mechanical Properties and Tests of Building Materials - 444 Water Resources - 444.2 Groundwater - 461.2 Biological Materials and Tissue Engineering - 461.9 Biology - 481.1 Geology - 481.2 Geochemistry - 483.1 Soils and Soil Mechanics - 801 Chemistry - 804.1 Organic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics - 921.6 Numerical Methods - 922 Statistical Methods - 922.2 Mathematical Statistics - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.20.013
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 35>

Accession number:20145100353418
Title:Error assessment of extracting morphological parameters of bank gullies by manual visual interpretation based on QuickBird imagery
Authors:Li, Zhen (1); Zhang, Yan (1); Yang, Song (1); Zhu, Qingke (1); Wu, Jianhui (1); Ma, Huan (1); He, Yuanmei (1)
Author affiliation:(1) Key Laboratory of Soil and Water Conservation and Desertification Combating, Ministry of Education, Beijing Forestry University, Beijing , China
Corresponding author:Zhang, Yan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:179-186
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:High-resolution satellite images such as those from Ikonos and QuickBird are increasingly available and are considered a valuable tool for extracting the consequences of gully erosion, and QuickBird imagery has been used to map gully features. To evaluate the accuracy of extracting morphological parameters of bank gullies including area, perimeter, and length from QuickBird imagery by manual visual interpretation, and to analyze the causes of errors, 20 bank gullies were selected in Hegou catchment and Qiaogou catchment located in the Loess Plateau of northern Shaanxi province, respectively. 3D laser scanner was used to measure the topography of bank gullies within two weeks after the QuickBird images were taken. The interval among measurement points of 3D laser scanner was set as 0.15 m. 3D laser scanner had been increasingly used to measure the topography as it can provide a high accuracy, non-contacted, penetrating and rapid method that enables the rapid production of accurate, high-resolution digital elevation model (DEM). Based on Delaunay triangulated irregular networks (TIN), then DEM with the pixel size of 0.15 m &times; 0.15 m was created using the 3D Analyst extension of ArcGIS 9.3. On this basis, the values of morphological parameters extracted from DEM were taken as actual values and errors of morphological parameters of bank gullies extracted from QuickBird imagery were determined. The average absolute error, maximum absolute error, average relative error, maximum relative error, and maximum relative error among different interpretation persons were used to assess the accuracy of manual visual interpretation of QuickBird imagery. The results showed that maximum relative error of area and perimeter ranged from 4.1% to 22.2% and 1.4% to 22.2% in Hegou catchment, respectively, while maximum relative error ranged from 2.4% to 22.6% for area and 4.5% to 29.7% for perimeter in Qiaogou catchment, respectively. Although maximum relative error appeared to be large for some gullies, average relative error of area and perimeter were both about 5% in two study areas. In addition, by overlaying the two valley regions extracted from QuickBird imagery and DEM, the area that the distance offsets was larger than 0.6 m (QuickBird image one pixel value) remained below 4%. Average relative error of gully length in Hegou catchment and Qiaogou catchment were about 2% and 5%, respectively, with corresponding average of the average absolute error of 0.5 m and 0.75 m. Correlation analysis showed that average relative error, maximum relative error and maximum relative error among different interpretation persons were negatively correlated with the area and length of bank gully (P&lt;0.05), which meant that the larger the area and length of bank gully were, the smaller the errors were. This suggested that choosing large gullies would reduce the errors when the morphological parameters were extracted manually from QuickBird imagery. The accuracy of manual visual interpretation was also influenced by the vegetation types near the gully boundary. Catchments which land was covered with native grassland had higher precision than those were covered with shrub and grass. Overall, QuickBird imagery can provide reliable data source for extracting morphological parameters of bank gullies. The results can provide the references for assessing gully erosion using QuickBird imagery at larger spatial scales rather than direct field measurements.
Number of references:27
Main heading:Landforms
Controlled terms:Catchments - Erosion - Errors - Forestry - Laser applications - Pixels - Remote sensing - Runoff - Satellite imagery - Scanning  - Sediments - Surveying
Uncontrolled terms:Bank gullies - Loess area - QuickBird imageries - Three dimensional - Visual interpretation
Classification code:405.3 Surveying - 443 Meteorology - 444 Water Resources - 444.1 Surface Water - 481.1 Geology - 483 Soil Mechanics and Foundations - 723.5 Computer Applications - 731 Automatic Control Principles and Applications - 731.1 Control Systems - 741.3 Optical Devices and Systems - 744.9 Laser Applications - 821.0 Woodlands and Forestry - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2014.20.022
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 36>

Accession number:20145100353414
Title:Determination of soil depth and its water threshold for diagnosing water deficit of winter wheat based on grain yield
Authors:Zhao, Yemeng (1); Liu, Xiaoying (1); Zhong, Xiuli (1); Cao, Jinfeng (1); Ren, Tusheng (2); Feng, Danhong (1)
Author affiliation:(1) Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences/Key Laboratory of Dry Land Agriculture, Ministry of Agriculture, Beijing , China; (2) College of Resources and Environmental Sciences, China Agricultural University, Beijing, China
Corresponding author:Liu, Xiaoying
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:147-154
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Clarifying response of crop yield to water deficit is important for deficit irrigation. Field experiment of winter wheat with seven treatments, irrigated at different growth stages and supplied with varying irrigation schedules to maintain their variation in soil water, was conducted at a site in Hengshui, Hebei Province in North China Plain. The well-watered control was given four irrigations, and the most stressed treatment was rainfed. Each treatment had three replicates with plot size of 12 m &times; 8 m and was arranged in a completely randomized block design. Soil water was measured by TDR within 1.6 m soil depth at 0.2 m interval. Grain yield was measured on three 8-m² area for each treatment. Meteorological data were collected through a weather station at the test site. By examining soil water dynamics, its average over growing season and its variability over soil profile, and by exploring the relations of grain yield of winter wheat with soil moisture of different depth at various growth stages, we determined suitable soil depth for detecting water deficit and its corresponding soil water threshold. We found that the largest difference in soil water between the deficit treated and well-watered control occurred at shallow soil layer, and the magnitude in difference decreased as soil depth increased, which was 19.7%-36.5%, 9.3%-21.7% and 2.9%-9.7% at the depth of 0-0.4, 0-0.8 and 0-1.2 m, respectively. Variability in soil water also reduced with increase of soil depth, shown by the average variation coefficient of all the treatments as 0.149, 0.129, 0.116, 0.108, 0.100 and 0.090 respectively for 0-0.4, 0-0.6, 0-0.8, 0-1.0, 0-1.2 and 0-1.6 m soil layer. Relationship between grain yield of winter wheat and soil water of various depths at different growth stages was described by downward-opening parabolic function, but the correlation significance changed with both growth stage and soil depth, being most significant during grain filling (coefficient of determination was 0.953-0.981, P&lt; 0.01) and at the soil layer of 0-0.4 m. Soil water threshold that affected grain yield decreased with progression of growing season. From jointing-booting to milk maturing, they reduced from 95.0%, 91.1%, 83.1%, 86.9% and 94.1% to 75.7%, 73.7%, 72.3%, 74.3% and 90.0% of the field water capacity for the soil layer of 0-0.4, 0-0.6, 0-1.0, 0-1.2 and 0-1.6 m, respectively, indicating a diminished sensitivity of winter wheat growth to water supply. These results, the largest difference and variability in soil water at shallow layer, as well as the most close correlation between yield and shallow-layer soil water, all pointed to the fact that 0-0.4 m was the most suitable soil depth for detecting water deficit since large variability can give a stronger signal to be detected. The corresponding water threshold at jointing-booting, heading, flowering, beginning-, middle-, late-grain filling and milk maturing was respectively 95.0%, 98.4%, 79.9%, 73.7%, 88.6%, 79.6% and 75.7%. Since the detection depth of soil water deficit has never been studied as an important variable for deficit irrigation and that most previous studies concern threshold affecting plant physiological process, our results are of practical value for guiding deficit irrigation practice in wheat production and for ease monitoring of soil water in Northern China agricultural production areas.
Number of references:23
Main heading:Grain (agricultural product)
Controlled terms:Crops - Grain growth - Irrigation - Meteorology - Plants (botany) - Soil moisture - Soils - Water resources - Water supply
Uncontrolled terms:Soil depth - Soil water - Soil water deficit - Winter wheat - Yield
Classification code:443 Meteorology - 444 Water Resources - 446.1 Water Supply Systems - 461.9 Biology - 483.1 Soils and Soil Mechanics - 821.3 Agricultural Methods - 821.4 Agricultural Products - 933.1.2 Crystal Growth
DOI:10.3969/j.issn.1002-6819.2014.20.018
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 37>

Accession number:20145100353408
Title:Coupled allocation model for optimizing water in canal-pond-field based on artificial bee colony and particle swarm algorithm
Authors:Chen, Shu (1); Shao, Dongguo (1); Li, Haoxin (1); Xu, Baoli (1)
Author affiliation:(1) State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China
Corresponding author:Shao, Dongguo
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:90-97
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the development of Chinese society and economy, contradiction between water supply and demand has become increasingly prominent. Consequently, the problem of agricultural water shortage becomes more serious. What's more, seasonal droughts have frequently taken place in the south of China in recent years, resulting in a serious impact on agricultural production. In order to alleviate the contradiction between water supply and demand of agricultural, to reduce losses caused by seasonal droughts, we proposed a model to optimize the allocation of water resources. Based on the consideration of the complex relationship of water conversion between the canals, ponds and fields in the southern irrigation area and the regulatory role of ponds which is less taken into consideration in the models built before, canal-pond optimal regulation has been proposed. Water flowed into ponds from canals in lower-intensity periods, which were used to irrigate crops in peak periods in the mode of canal-pond optimal regulation. Then an optimal operation model for coupling canal-pond regulation and water allocation between crops has been set up, with the goal of maximizing the economic benefits in the whole irrigated region. Channel water diversion and crop irrigation water at each period were treated as decision variables in the model. The responses of different crops to water deficit during the same period, the responses of the same crop to water deficit in different periods and the regulatory role of ponds were all taken into consideration in the model. Problems solved by the model were high-dimensional, complex, non-linear optimization problems. And the PSO-ABC hybrid algorithm was used to solve the model according to the characteristics of the model. Artificial bee colony algorithm is one of the current best evolutionary algorithms with advantages of simple principle, easy implementation, less parameters and quick convergence speed. But it still suffered from the problems of premature convergence when it came to the high-dimensional complex optimization problem. However, the particle swarm optimization algorithm has a strong ability to jump out of the local extremum. Then the PSO-ABC hybrid algorithm was proposed and used to solve these problems. The coupled model was applied to Zhanghe irrigation region, and compared with the following two models. In model 1, ponds supplied water first and then canals and water distribution between crops accorded to the proportion of crop water demand, which meant that neither canal-pond optimal regulation nor water allocation optimization between crops was considered. In model 2, ponds also supplied water first and only water allocation optimization between crops was considered. The results showed that the proposed model was remarkable in optimizing aspect. In three typical years, the number of water shortage periods decreased significantly. And the total water shortage periods were 91.4% lower than that of the model 1. In special dry years (rainfall for rate 95%), agricultural benefits were 20.7% and 6.9% higher than that of the other two models, respectively. In dry years (rainfall for rate 75%), agricultural benefits were 10.3% and 3.2% higher than that of the other two models, respectively. PSO-ABC hybrid algorithm is less time consuming, and it has advantages to solve the optimal model in consideration of multiple water sources, long distance water transmission and reservoir -pond co-regulation.
Number of references:29
Main heading:Reservoirs (water)
Controlled terms:Crops - Drought - Economics - Flood control - Irrigation - Irrigation canals - Lakes - Models - Nonlinear programming - Optimization  - Particle swarm optimization (PSO) - Ponds - Problem solving - Rain - Water - Water management - Water supply - Water supply systems
Uncontrolled terms:Artificial bee colony algorithms - Complex optimization problems - Coupled modeling - Hybrid algorithms - Non-linear optimization problems - Optimal allocation - Particle swarm algorithm - Particle swarm optimization algorithm
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 441.2 Reservoirs - 443.3 Precipitation - 444 Water Resources - 446 Waterworks - 446.1 Water Supply Systems - 454.1 Environmental Engineering, General - 454.3 Ecology and Ecosystems - 821.3 Agricultural Methods - 821.4 Agricultural Products - 902.1 Engineering Graphics - 921 Mathematics - 921.5 Optimization Techniques - 971 Social Sciences
DOI:10.3969/j.issn.1002-6819.2014.20.012
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 38>

Accession number:20145100353410
Title:Effect of thermokarst lake on soil saturated hydraulic conductivity and analysis of its influenced factors
Authors:Gao, Zeyong (1); Wang, Yibo (1); Liu, Guohua (1)
Author affiliation:(1) College of Earth and Environment Sciences, Lanzhou University, Lanzhou, China; (2) State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences (CAS), Lanzhou , China
Corresponding author:Wang, Yibo
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:109-117
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Thermkarst lakes as a typical landform unit are widely distributed in permafrost areas of the source region of the Yangtze River. The thermokarst lakes can have huge impact on soil properties, permafrost distribution, eco-hydrological processes, etc. on the lakeshore area with its development process. In this study, we analyzed the influence factors on physical and chemical properties of soil and made comparative analysis of the spatial difference of soil saturated hydraulic conductivity in the undisturbed lakeshore area, the dead root area of lakeshore, saline soil area of lakeshore and different slope areas around a typical thermokarst lake in permafrost areas of the source region of Yangtze River. Our results showed that soil saturated hydraulic conductivity differed among soils from different areas. The soil saturated hydraulic conductivity was in an order of dead root area of lakeshore &gt; undisturbed lakeshore area &gt; saline soil area of lakeshore. Compared with the soil of undisturbed lakeshore area, the soil saturated hydraulic conductivity of the dead root area of lakeshore increased by 70.1%, while the saline soil area decreased by 33.8%. The results showed soil environment had a great change with the formation of thermkarst lakes. The results suggested that the formation of the dead root area of lakeshore led to an increase in soil saturated hydraulic conductivity and a decrease of runoff capacity. Opposite results were found with the saline soil. At different slope areas of lakeshore, the greater the slope was, the greater the soil saturated hydraulic conductivity. Furthermore the maximum difference appeared at the middle position of the slope while soil saturated hydraulic conductivity of slope bottom did not obviously changed. The results also showed that with the different effects of thermkarst lakes, the cause of the variation of soil saturated hydraulic conductivity at the different areas was coupled with the influences of vegetation coverage, soil organic matter content, and particle size distribution. When soil Pedo-transfer functions (PTFs) were used to predict soil saturated hydraulic conductivity, above factors must be considered. We used three models, ROSETTA, CAMPBELL and VAUCLIN to evaluate their predictive ability by comparing the simulated results with the measured values and found that VAUCLIN model was the most reliable one to predict soil saturated hydraulic conductivity of the alpine meadow in permafrost areas of the source region of Yangtze River. The study of soil hydraulic parameters in different affected area of thermokarst lakes can provide valuable information for the study of regional soil erosion, runoff models and hydrologic processes.
Number of references:44
Main heading:Soils
Controlled terms:Chemical analysis - Computer simulation - Erosion - Factor analysis - Hydraulic conductivity - Lakes - Particle size - Particle size analysis - Permafrost - Rivers  - Runoff - Transfer functions - Transport properties - Water content
Uncontrolled terms:Influence factor - Pedo-transfer functions - Physical and chemical properties - Saturated hydraulic conductivity - Soil hydraulic parameters - Soil organic matter contents - Source region of the yangtze rivers - Thermokarst lakes
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 407.2 Waterways - 444 Water Resources - 444.1 Surface Water - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 632.1 Hydraulics - 723.5 Computer Applications - 801 Chemistry - 804 Chemical Products Generally - 921 Mathematics - 922.2 Mathematical Statistics - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.20.014
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 39>

Accession number:20145100353431
Title:Influence of soil erosion thickness on soil productivity of black soil and its evaluation
Authors:Liu, Hui (1); Wei, Yongxia (1)
Author affiliation:(1) College of Water Conservancy and Architecture, Northeast Agricultural University, Harbin, China; (2) Collaborative Innovation Center of Grain Production Capacity Improvement in Heilongjiang Province, Harbin , China; (3) Key Laboratory of High Efficiency Utilization of Agricultural Water Resources of the Ministry of Agriculture, Harbin , China; (4) Key Laboratory of Water-saving Agriculture of Ordinary University in Heilongjiang Province, Harbin , China
Corresponding author:Wei, Yongxia
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:288-296
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil erosion is one of the most widespread ecological problems in the world. It accelerates the process of land desertification, causes soil degradation and soil productivity reduction; affects the agricultural development and food security; and seriously restricts the sustainable development of society, economy, and ecology in the world. In the black soil region of Northeast China, where is the most important grain production area and one of six soil erosion regions in China, serious soil erosion causes a decrease in the black soil thickness, leading to a steep decline in soil productivity. In this study, the influence of soil erosion thickness on the indexes of soil physicochemical properties, soybean biological traits and water use efficiency in the black soil region were studied in a pot experiment in 2012 and 2013. The tested soil was obtained from 0, 5, 10, 15, 20, 25, and 30 cm below the surface layer to simulate the plough layer soil with soil erosion thickness of 0, 5, 10, 15, 20, 25, and 30 cm. A quantitative model of soybean yield in the black soil region on the soil erosion thickness was established to explore the response of soybean yield to soil erosion thickness. Combining the physical and chemical properties of the soil in the experimental zone, the TOPSIS model is improved, by which the soil productivity under different soil erosion thickness was evaluated. The results showed that soil erosion thickness had a significant influence on many important indicators of soil quality. Total N, alkaline hydrolysis N, total P, available P, organic matter content, and field moisture capacity decreased, whereas soil bulk density increased. With the increase in erosion thickness; total K and available K contents had no remarkable changes. Soil erosion thickness also had a significant influence on soybean growth, which was mainly reflected by the reduction in plant height, decreased in the number of pods and grains per plant, resulting in decrease of soybean yield. With the increase of the soil erosion thickness, soybean yield reduction rate increased in a S-shaped curve, soybean yield and water consumption decreased in a Z-shaped curve, while water use efficiency decreased in the form of exponential function. The TOPSIS and improved TOPSIS models were used to calculate the soil productivity indexes under different soil erosion thicknesses, and a comparative analysis was carried out between the results of the two models and the commonly used fuzzy matter-element model. The three models had a high consistency in the soil productivity evaluation, and among which the improved TOPSIS model was the most adequate one. The soil productivity indexes calculated by the fuzzy matter-element and TOPSIS models showed a good linear relationship with soil erosion thickness, while the indexes calculated by the improved TOPSIS model showed a Z-shaped curve, which was consistent with the change of soybean yield. To further analyze the evaluation results of the three models, regression analysis was conducted on the soil productivity indexes and the soybean yield. The result showed that, soybean yield had a linear relationship with the soil productivity indexes calculated by the fuzzy matter-element and TOPSIS models but an exponential relationship with that calculated by the improved TOPSIS model. The soil productivity indexes calculated by the improved TOPSIS model developed from this study can properly reflect the soil productivity levels under different soil erosion thicknesses and can be used for the evaluation of soil productivity. The results will provide a more reasonable and reliable evaluation method and valuable information for further study on soil erosion prevention and control in the black soil region.
Number of references:23
Main heading:Soil conservation
Controlled terms:Alkalinity - Crops - Ecology - Erosion - Exponential functions - Food supply - Grain (agricultural product) - Productivity - Regression analysis - Soils  - Water supply
Uncontrolled terms:Black soil region of northeast chinas - Black soil regions - Evaluation - Fuzzy matter-element models - Physical and chemical properties - Soil physico-chemical properties - Soil productivity - TOPSIS models
Classification code:404.2 Civil Defense - 407 Maritime and Port Structures; Rivers and Other Waterways - 446.1 Water Supply Systems - 454.3 Ecology and Ecosystems - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 801.1 Chemistry, General - 821.4 Agricultural Products - 913.1 Production Engineering - 921 Mathematics - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2014.20.035
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

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Accession number:20145100353436
Title:Longevity analysis of biosensor for Salmonella typhimurium detection in food
Authors:Ye, Xuemei (1); Hu, Jiajia (1); Hu, Jing (1)
Author affiliation:(1) Jiangsu Key Laboratory of Materials Surface Technology, Changzhou University, Changzhou, China; (2) Center of Food Detection and Safety, Auburn University, Auburn; AL, United States
Corresponding author:Hu, Jing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:20
Issue date:October 15, 2014
Publication year:2014
Pages:334-338
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:A biosensor essentially consists of two main components, a physical transducer and a biorecognition element. In this study, antibody-based magnetoelastic (ME) biosensor specific to Salmonella typhimurium has been developed by immobilizing biorecognition element onto the physical transducer. Rabbit polyclonal antibody, which was an immune system-related protein called immunoglobulins, was used as the biorecognition. A magnetostrictive platform was served as the transducer, since it offered wireless or remote detecting, which was a unique advantage over conventional sensor platforms. Amorphous magnetostrictive alloy was used as the sensor platform, which was mechanically polished using fine grit paper to reduce the thickness to 15 &micro;m to decrease the initial mass, and magnetostrictive strips were made with the size of 5 mm&times;1 mm using an auto controlled, microdicing saw. Then the diced sensors were ultrasonically cleaned in methanol solution to remove grease and debris left by the dicing process. And antibody was immobilized on the magnetostrictive platform using Langmuir-Blodgett (LB) technique, in which seven monolayers containing antibody were transferred onto the magnetostrictive sensor surface using a LB film balance KSV 2200 LB. After antibody immobilization, the biosensors were divided into 3 sets and maintained in 3 constant temperature humidity chambers with temperature of 25, 45 and 65, respectively. Before testing, the biosensors were allowed to attain room temperature and then immersed in S. typhimurium solution with the concentration of 1&times;10⁹ cfu/mL for 30 minutes to bind bacterial cells. Due to the magnetoelastic nature of the amorphous magnetostrictive alloy, the sensor exhibited a physical resonance when it underwent a time-varying magnetic field, and a shift in resonance frequency of the magnetostrictive sensor depended only on the mass change when testing environmental parameters were invariable. In this study, the environment was kept constant, and the changes in the resonance frequency of biosensors attributting to the binding of Salmonella typhimurium were recorded by HP network analyzer 8751A over the testing period, and the binding was also confirmed by scanning electron microscopy (SEM) micrographs. According to the shift in resonance frequency due to the binding of Salmonella typhimurium, the binding density bound on the biosensor was calculated. In order to confirm the binding, different regions of each sensor surface were examined and photographed using SEM, the number of cells bound to the sensor surface was directly counted from SEM images and statistically converted to an area density of bacteria attached to the sensor surface, and then compared with that calculated from the shift in resonance frequency. The longevity of the sensors at different temperatures was investigated according to the binding density of Salmonella typhimurium. Meanwhile, the activation energy was calculated using Arrhenius Equation. The results showed that at each temperature, the binding ability of antibody to S. typhimurium decreased gradually over the testing period, and the higher the temperature, the lower the longevity of the biosensor. The longevity of polyclonal antibody-based magnetostrictive sensor was about 30, 8 and 5 days at 25 (room temperature), 45 and 65, respectively. And its activation energy calculated by Arrhenius Equation was about 13.024 kJ/mol.
Number of references:26
Main heading:Biosensors
Controlled terms:Ability testing - Activation energy - Antibodies - Binding energy - Food microbiology - Food safety - Langmuir Blodgett films - Magnetostrictive devices - Natural frequencies - Salmonella  - Scanning electron microscopy - Temperature - Transducers
Uncontrolled terms:Biorecognition elements - Environmental parameter - Langmuir Blodgett techniques - Longevity - Magnetostrictive sensors - Magnetostrictive strips - Salmonella typhimurium - Time-varying magnetic fields
Classification code:461 Bioengineering and Biology - 641.1 Thermodynamics - 704 Electric Components and Equipment - 711.1 Electromagnetic Waves in Different Media - 714 Electronic Components and Tubes - 715 Electronic Equipment, General Purpose and Industrial - 732 Control Devices - 741.1 Light/Optics - 801.4 Physical Chemistry - 912.4 Personnel
DOI:10.3969/j.issn.1002-6819.2014.20.040
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.