2015年第6期
2015年第46卷第6期共收錄53篇
<RECORD 1>
Accession number:20152801011239
Title:Influence of balance hole diameter on performance and balance chamber pressure of centrifugal pump
Authors:Dong, Wei (1); Chu, Wuli (1)
Author affiliation:(1) School of Power and Energy, Northwestern Ploytechnical University, Xi'an, China; (2) Collaborative Innovation Center of Advanced Aero-Engine, Beijing, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:73-77
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Numerical simulations based on CFD had been performed by the IS150-125-315 single-stage single-suction centrifugal pump. The numerical results showed a good agreement with the experimental measurements. The performance, i.e., head, efficiency and shaft power of pump were studied under five balance hole diameters. For each of the diameter, the spatial distribution law of balance cavity pressure was researched. The influence of holes diameter on shroud force was analyzed and the relation curve p¯=f(k¯) was further drew. The results showed that the head had no relation with balance hole diameter when the flow rate was larger than design flow condition. After balance hole diameter increased to a certain value, shaft power was obviously increased and the efficiency was reduced at the same flow condition. The differential pressure of centrifugal pump without balance holes is larger than that with balance holes at the same massflow. Balance cavity pressure of the holes with the same diameter increased along radial direction from pump shaft to seal ring, while the change of its value was negligible along axial and tangential directions. In the region where the radius was less than the vertical distance between balance holes center and pump shaft center, a smaller diameter of balance cavity made the pressure approach zero. Out of this radius, the pressure increased as the balance hole diameter increased. When k¯≥2.645, the shroud force on the balance cavity almost achieved balance. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:15
Main heading:Seals
Controlled terms:Centrifugal pumps - Computational fluid dynamics - Computer simulation - Numerical models - Pumps
Uncontrolled terms:Balance holes - Chamber pressure - Differential pressures - Numerical results - Performance prediction - Radial direction - Spatial distribution laws - Tangential directions
Classification code:618.2 Pumps - 619.1.1 Pipe Accessories - 723.5 Computer Applications - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2015.06.011
Database:Compendex
<RECORD 2>
Accession number:20152801011236
Title:Researches and developments of axial-flow pump system
Authors:Liu, Chao (1)
Author affiliation:(1) School of Hydraulic, Energy and Power Engineering, Yangzhou University, Yangzhou, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:49-59
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The low head pump system, mainly axial-flow pump system research and technological innovation in China are introduced. The research and development trend on hydraulic performance of the axial flow pump system are discussed. The applications of high speed axial-flow pump hydraulic model and development progress are presented. Through inductive characteristics of axial-flow pump system, the classification of the system is put forward according to the installation position of the motor, namely the shaft extension type axial-flow pump system and the tubular axial-flow pump system. The innovation applying of the different types of axial-flow pump systems in a quantity pumping station projects is introduced respectively. From the perspective of technological development, the development trends and application prospects of axial-flow pump system are analyzed. The limitations of the traditional pump selection method are discussed, and the applicable rationality of a new method of pump selection for the axial-flow pump system is introduced. The variable angle adjustment formula and applicability based on the test data of axial-flow pump system are introduced. The harmfulness to the pump units from the intake vortex and the safety policies are analyzed. The research results of the vortices in the pump sump and the measures of vortices prevention and elimination are described. As regarding the real and potential problems in research development on axial-flow pump system, the suggestions for further deepen researches are presented. Although the hydraulic performance of axial flow pump system research has reached a higher level, but possibility of partial breakthroughs still exists. The future research direction of pump system should be more to the structural optimization, the pump system reliability and adaptability, vibration and noise, and run quality promotion. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:55
Main heading:Pumps
Controlled terms:Axial flow - Hydraulic models - Structural optimization - Vortex flow
Uncontrolled terms:Axial flow pump - Future research directions - Hydraulic performance - Pump selection - Pump system - Research and development - Technological development - Technological innovation
Classification code:618.2 Pumps - 631.1 Fluid Flow, General - 632.1 Hydraulics - 921.5 Optimization Techniques
DOI:10.6041/j.issn.1000-1298.2015.06.008
Database:Compendex
<RECORD 3>
Accession number:20152801011238
Title:Experimental investigation on pressure fluctuation and vibration in axial-flow pump model
Authors:Zhang, Desheng (1); Geng, Linlin (1); Shi, Weidong (1); Pan, Dazhi (1); Wang, Haiyu (1)
Author affiliation:(1) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:66-72
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A series of pressure fluctuation and vibration acceleration were measured at the key monitoring points under the speeds of 1450, 1200, 1000 r/min, and their correlations were discussed. The experimental results showed that the peak to peak values of the pressure fluctuation didn't obey the pump similarity law. The pressure fluctuation patterns were different under different rotating speeds. The maximum peak-to-peak value moved from the impeller inlet to the guide vane outlet with the rotating speed increased. The main frequency at impeller inlet was the blade passing frequency (BPF) under different rotating speeds, and the main frequency in impeller outlet and guide vane outlet were slightly lower than the blade passing frequency with rotating speed increased. The amplitude at the impeller outlet was increased firstly, and then decreased, while it was always increased at the guide vane outlet with rotating speed increased. The vibrations at different positions in the model pump mainly included shaft frequency which was induced by mass unbalance of rotor system and the low frequency induced by the unsteady fluid in pump. In the frequency ranged from about 0 to 2 times, the pressure pulsation and vibration tendency was substantially the same, and the speed variations had a similar effect on both of them. There were main 1~4 times rotation frequencies in pressure fluctuation frequency domain at different monitoring points, which were changed under different rotating speeds, while only 1 and 2 times of shaft rotation frequency played the main role in the vibration frequency domain at different monitoring locations. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:18
Main heading:Speed
Controlled terms:Axial flow - Experiments - Flow measurement - Frequency domain analysis - Impellers - Rotating machinery
Uncontrolled terms:Axial flow pump - Axial-flow pump models - Blade passing frequency - Experimental investigations - Frequency spectra - Pressure fluctuation - Vibration - Vibration acceleration
Classification code:601.1 Mechanical Devices - 601.2 Machine Components - 631.1 Fluid Flow, General - 731.1 Control Systems - 901.3 Engineering Research - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2015.06.010
Database:Compendex
<RECORD 4>
Accession number:20152801011241
Title:Impeller design with alternate loading technique for double-suction centrifugal pumps
Authors:Wang, Fujun (1); Yao, Zhifeng (1); Yang, Wei (1); Xiao, Ruofu (1); Leng, Hongfei (1)
Author affiliation:(1) Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System, China Agricultural University, Beijing, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:84-91
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The pressure pulsation in double-suction centrifugal pump is one of the key factors affecting the stability of pump unit operation. In order to reduce the pressure pulsation, the main causes of pressure pulsations in double-suction centrifugal pump were analyzed. The effects of blade loading curves on flow patterns in pumps were investigated. The relations between blade loading, blade outlet obliquity, staggered angle and the flow features including secondary flow and pressure pulsation were established. A new impeller design method with alternate loading was proposed. In the new design method, the main loading point on shroud located at the front of blade loading curve, and the main loading point on hub located at the rear of its curve. The impeller designed by this method was in the type of staggered arrangement in circumferential direction. The blade outlet edge was tilted forward, and the wrap angle difference between shroud and hub was very small. The field test on a large irrigation pumping station showed that the dominant frequency of pressure pulsations in the double-suction centrifugal pump designed by using this method was reduced significantly. The optimum efficiency and high-efficiency-range of the pump were also improved. This method could be used as a new approach to design/redesign double-suction centrifugal pumps with large power. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:20
Main heading:Pumps
Controlled terms:Centrifugal pumps - Design - Gears - Impellers
Uncontrolled terms:Circumferential direction - Dominant frequency - Double-suction centrifugal pumps - Hydraulic designs - Loading technique - Optimum efficiency - Pressure pulsation - Staggered arrangement
Classification code:408 Structural Design - 601.2 Machine Components - 618.2 Pumps
DOI:10.6041/j.issn.1000-1298.2015.06.013
Database:Compendex
<RECORD 5>
Accession number:20152801011278
Title:Dither compensation technology for hysteresis of bi-direction thrust torsion coupling
Authors:Liu, Guowen (1); Li, Sheng (1); Ruan, Jian (1); Jiang, Haibing (1); Shentu, Shengnan (1); Kong, Chenjing (1)
Author affiliation:(1) Key Laboratory of E&M, Ministry of Education, Zhejiang University of Technology, Hangzhou, China; (2) College of Mechanical Engineering, Quzhou University, Quzhou, China
Corresponding author:Ruan, Jian
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:349-354
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A novel design project of bi-direction thrust torsion coupling was put forward for 2D electro-hydraulic proportional directional valve by using spherical roller, the wedge's linear motion could be translated into spool's rotary motion, and the output torque and 2D spool's torsion angle could be amplified. On the basis of the mathematical model, the dynamic characteristic of thrust torsion coupling and the hysteresis characteristics due to backlash were analyzed by using phase-plane analysis method. The backlash was overcome by using dither compensation technology and the effect for eliminating the backlash was achieved. Based on the mathematical model and the prototype, the relationship between linear motion of the wedge and rotation angular displacement of the spool was researched and simulated. Simulation and experimental results were consistent. Experimental results showed that the hysteresis of backlash could be reduced efficiently by using dither compensation technology, the hysteresis was about 3.7% as dither amplitude was half of backlash, and it could be controlled below 2%, as dither amplitude was beyond the backlash. Bi-direction thrust torsion coupling could be used in the 2D electro-hydraulic proportional directional valve and the amplification of the displacement could be realized. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:14
Main heading:Torsional stress
Controlled terms:Hysteresis - Reels
Uncontrolled terms:Angular displacement - Compensation technology - Dynamic characteristics - Electro-hydraulics - Hysteresis characteristics - Phase-plane analysis - Spherical rollers - Torsion coupling
Classification code:421 Strength of Building Materials; Mechanical Properties - 742.2 Photographic Equipment - 961 Systems Science
DOI:10.6041/j.issn.1000-1298.2015.06.050
Database:Compendex
<RECORD 6>
Accession number:20152801011274
Title:Dynamic analysis of decoupled spherical parallel mechanism for vectored thruster
Authors:Zhang, Rongmin (1); Chen, Yuan (1); Gao, Jun (1)
Author affiliation:(1) School of Mechanical, Electrical & Information Engineering, Shandong University, Weihai, China
Corresponding author:Gao, Jun
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:319-326
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The thrust vectoring technology is becoming a research hotspot for underwater vehicle. Combination of spherical parallel mechanism with propeller makes an approach to the above technology. A new type of decoupled 2-DOF spherical parallel mechanism was proposed for vectored thruster of underwater vehicle. Based on the screw theory, the degree of freedom was calculated, and the direct and inverse kinematics solutions were obtained by using analytic geometry. The first-order kinematic influence coefficient was employed to deduce the Jacobian matrix. The detailed dynamic model was got by the Newton-Euler equation and hydrodynamic of ship propulsors. Corresponding numerical examples were finally given to verify the effectiveness of all above methods. The proposed spherical parallel mechanism is simple in construction, convenient to control and has good decoupling performance. In conclusion, it shows superiority for vectored thruster in engineering application. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:19
Main heading:Mechanisms
Controlled terms:Airships - Degrees of freedom (mechanics) - Inverse kinematics - Inverse problems - Jacobian matrices - Kinematics - Numerical methods - Research aircraft - Screws - Ship propulsion - Spheres
Uncontrolled terms:Analytic geometries - Engineering applications - Inverse kinematics solutions - Kinematic influence coefficient - Newton Euler equation - Screw theory - Spherical parallel mechanism - Thrust vectoring
Classification code:601.3 Mechanisms - 605 Small Tools and Hardware - 631 Fluid Flow - 652.1 Aircraft, General - 652.5 Balloons and Gliders - 675.1 Ship Propulsion (Before 1993, use code 671) - 921 Mathematics - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2015.06.046
Database:Compendex
<RECORD 7>
Accession number:20152801011234
Title:Design and experiment of 2-DOF clamp-type manipulator for transplanting of rice potted-seedlings
Authors:Ma, Ruijun (1); Fan, Yuanjun (1); Huang, Qian (1); Huang, Mushui (1); Zhang, Yali (1)
Author affiliation:(1) College of Engineering, South China Agricultural University, Guangzhou, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:35-43
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A new kind of 2-DOF clamp-type manipulator was developed relying on the feature and principle of 2-DOF manipulator for automatically pulling up and transplanting multiple cell-tray potted-seedlings. The characteristics of operating targets, main structure and control circuit of the manipulator were described. The key component of seedling clamp mechanism was designed, and 3D structure model was established and virtually assembled by using Pro/E. Dynamics simulation to the seedling clamp mechanism ensured the reliability of its opening and closing process. Preliminary performance experiment was conducted on a program controlled prototype platform. Four related factors were considered, including the type of cell-tray, moisture of soil ball, extending force of clip's spring and feeding mode of cell-tray. And the effect of above factors on the evaluate index of successful pulling up rate of the manipulator was analyzed. Results showed that type of cell-tray and moisture of soil ball both had very significant effects on successful pulling up rate (P<0.01), while no significant difference for both extending force of clip's spring (15, 22 N) and feeding mode of cell-tray (P>0.05). When the extending force of clip's spring and feeding mode of cell-tray were unchanged, cultivating the potted-seedlings by using red tray or maintaining moisture of soil ball of potted-seedling above 30% can increase successful pulling up rate. And the performance of seedlings automatic transporting and feeding mechanism can meet the requirements of transporting and feeding cell-tray potted-seedlings row-by-row. The results provide a useful reference for subsequent optimization on manipulator's performance. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:21
Main heading:Manipulators
Controlled terms:Cells - Cytology - Design - Experiments - Feeding - Moisture - Soil moisture - Soils
Uncontrolled terms:Control circuits - Dynamics simulation - Evaluate indices - Feeding mechanism - Main structure - Performance experiment - Related factors - Rice potted seedling
Classification code:408 Structural Design - 461.2 Biological Materials and Tissue Engineering - 483.1 Soils and Soil Mechanics - 691.1 Materials Handling Equipment - 691.2 Materials Handling Methods - 801.4 Physical Chemistry - 901.3 Engineering Research
DOI:10.6041/j.issn.1000-1298.2015.06.006
Database:Compendex
<RECORD 8>
Accession number:20152801010860
Title:Ultrasonic testing method for localized void defect identification in thick section composites
Authors:Chen, Yuechao (1); Zhou, Xiaojun (1); Yang, Chenlong (1); Li, Zhao (1); Zheng, Huifeng (2)
Author affiliation:(1) The State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou, China; (2) College of Metrology & Measurement Engineering, China Jiliang University, Hangzhou, China
Corresponding author:Zhou, Xiaojun
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:372-378
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The ultrasonic pulse echo method was adopted to test the localized void defects in thick section composites and the extracted ultrasonic backscattered signal was analyzed. The results showed that the resonance structure noise may appear in the near surface region of the material. The voids can result in frequency reduction and amplitude decrease of the structure noise. The backscattered signal was back to normal state in the far surface region and the voids can lead to the appearance of low amplitude echo. The localized void identification method based on the backscattered signal processing was proposed. The near surface signal was processed by a modified S-transform to generate time-frequency coefficient matrix. The minimum and gain of the signal main frequency can be calculated to identify the voids. For the far surface signal, the wavelet transform modulus maximum denoising method was applied firstly, and then the denoised signal was processed by the modified S-transform to generate time-frequency coefficient matrix. Finally, the maximum and gain of the signal main frequency could be calculated to identify the voids. The experiments were implemented for the thick section composite plate specimen and curved surface specimen, respectively. The results showed that the localized void defects in thick section composites could be effectively identified by this signal process method. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:18
Main heading:Ultrasonic testing
Controlled terms:Electromagnetic wave backscattering - Mathematical transformations - Signal processing - Testing - Wavelet transforms
Uncontrolled terms:Backscattered signal - Identification method - Modified s transforms - Near surface regions - Ultrasonic pulse-echo method - Ultrasonic testing method - Wavelet modulus maxima - Wavelet transform modulus maxima
Classification code:423.2 Non Mechanical Properties of Building Materials: Test Methods - 711 Electromagnetic Waves - 716.1 Information Theory and Signal Processing - 921.3 Mathematical Transformations
DOI:10.6041/j.issn.1000-1298.2015.06.053
Database:Compendex
<RECORD 9>
Accession number:20152801011246
Title:Transport characteristics of water and nitrogen under bubbled-root irrigation with fertilizer solution
Authors:Fei, Liangjun (1); Fu, Yuliang (1); He, Zhenjia (1); Nie, Weibo (1); Wang, Bo (1); Wang, Longfei (1)
Author affiliation:(1) Institute of Water Resources, Xi'an University of Technology, Xi'an, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:121-129
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to improve the utilization rates of water and fertilizer and reduce the loss of nitrogen fertilizer and deep seepage under bubbled-root irrigation, the change features of soil wetted body as well as the water and nitrogen movement characteristics with different fertilizer solution concentrations were studied. The relation between the cumulative infiltration volume and transportation distance of wetting front with the change of solution concentration was presented. Besides, the empirical models for cumulative infiltration volume and wetting front transportation distance were established under bubbled-root irrigation; the impact of fertilizer solution concentration on the distribution laws of NO<inf>3</inf><sup>-</sup>-N and NH<inf>4</inf><sup>+</sup>-N content within the scope of infiltration depth was analyzed. The results of the experiment showed that when the liquid concentration was increased, the cumulative infiltration in unit area was increased with time, and both infiltration amount and wetting front transportation distance showed remarkable power function relationship with infiltration time. The determination coefficients were up to 0.98 and 0.96, respectively, which were greater than the critical correlation index (0.605 5); in the redistribution of infiltration, the liquid concentration of 41.7 g/L could guarantee better water absorption of jujube root, the influences of different concentrations of nitrogen on conversion rate of soil were different, the conversion rate of nitrate nitrogen was not significant, and the conversion rate of ammonium nitrogen of 33.3 g/L was the highest. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:23
Main heading:Infiltration
Controlled terms:Fertilizers - Irrigation - Nitrogen - Nitrogen fertilizers - Water absorption - Wetting
Uncontrolled terms:Bubbled-root irrigations - Cumulative infiltrations - Determination coefficients - Nitrogen transport - Solution infiltration - Transport characteristics - Transportation distance - Wetted body
Classification code:802.3 Chemical Operations - 804 Chemical Products Generally - 821.3 Agricultural Methods
DOI:10.6041/j.issn.1000-1298.2015.06.018
Database:Compendex
<RECORD 10>
Accession number:20152801011257
Title:Research of oil uptake and distribution of fried lotus root slices based on confocal laser scanning microscopy
Authors:Zhu, Yaodi (1); Zou, Xiaobo (1); Zhao, Jiewen (1); Shi, Jiyong (1); Guo, Yaning (1)
Author affiliation:(1) School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:207-211 and 232
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Recent consumer trends towards healthier and low fat products have had a significant impact on the snack industry. Vacuum and atmospheric frying of lotus root slices were compared, in terms of oil uptake under same pretreatment conditions. The objective of this study was to examine the most important quality parameters of vacuum frying and atmospheric frying lotus root slices in order to identify the specific advantages of vacuum technology and to understand the relationship between key microstructural changes and oil absorption. Confocal laser scanning microscopy is a new technology that can be used to observe the microstructure of fried lotus root slices after vacuum frying and atmospheric frying. Vacuum frying was shown to be a promising technique that can be used to reduce oil content. when using a driving force of ΔT=60, vacuum frying slices absorbed less than 30% of the oil absorbed by atmospheric frying ones. In addition, the results showed that after frying, the cellular structures were well conserved in terms of shape and size. Oil was shown to be mainly located in the surface of the crust occupying. Oil remained in the cut cells emptied during the washing or the frying operation or in the damaged cells partially filled with starch. Cell detachment, because of starch swelling and dehydration, seemed to be the preferential connection between cell layers. The positive effect of vacuum frying toward oil uptake reduction could be the restriction of these connections. Overall, this study has an important significance for decreasing oil uptake in terms of microstructural changes. Besides, it provides reliable data and effective study means for the future. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:19
Main heading:Cytology
Controlled terms:Cells - Confocal microscopy - Laser applications - Mobile security - Scanning - Starch - Surface analysis - Vacuum technology
Uncontrolled terms:Confocal laser scanning microscopy - Lotus root slices - Oil absorption - Oil distributions - Vacuum frying
Classification code:423 Non Mechanical Properties and Tests of Building Materials - 461.2 Biological Materials and Tissue Engineering - 633 Vacuum Technology - 741.3 Optical Devices and Systems - 744.9 Laser Applications - 804.1 Organic Compounds - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2015.06.029
Database:Compendex
<RECORD 11>
Accession number:20152801011260
Title:Factors influencing gelling properties of low acyl gellan/sodium caseinate mixtures
Authors:Chen, Qing (1); Wang, Lei (1); Xiang, Qirui (1)
Author affiliation:(1) School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:226-232
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The effect of low acyl gellan (LA)/sodium caseinate (SC) weight ratio, total polymer concentration, ion valence and cation concentration on the gelling properties of low acyl gellan-sodium caseinate mixtures were investigated by using compression tests. The results showed that ion valence and cation concentrations had a pronounced effect on the gel strength of low acyl gellan-sodium caseinate mixed gels. The failure strain of mixed gels decreased with the increase of cation concentrations. Moreover, the failure strain was less sensitive to LA/SC weight ratios and total polymer concentrations. The failure stress and Young's modulus of mixed gels increased with the increase of total polymer concentrations and the proportion of low acyl gellan. Moreover, at each LA/SC weight ratio and total polymer concentration, the failure stress and Young's modulus increased with the increase of cation until cation concentration reached a critical level, after which further increases in cation resulted in a reduction of failure stress and Young's modulus. At optimum cation levels, mixed gels with Mg<sup>2+</sup> were stronger than that with Na<sup>+</sup>. Water holding capacity of mixed gels decreased as cation concentrations increased. The higher the total polymer concentration and LA/SC weight ratio, the better the water holding capacity. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:23
Main heading:Positive ions
Controlled terms:Compression testing - Copolymers - Elastic moduli - Gelation - Gels - Mixtures - Polymers
Uncontrolled terms:Gelling properties - Influence factors - Low acyl gellan - Sodium caseinate - Water holding capacity
Classification code:421 Strength of Building Materials; Mechanical Properties - 801 Chemistry - 802.3 Chemical Operations - 804 Chemical Products Generally - 815.1 Polymeric Materials - 943 Mechanical and Miscellaneous Measuring Instruments - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2015.06.032
Database:Compendex
<RECORD 12>
Accession number:20152801011265
Title:Weed reverse positioning method and experiment based on multi-feature
Authors:Chen, Yajun (1); Zhao, Bo (2); Li, Shujun (2); Liu, Lei (2); Yuan, Yanwei (2); Zhang, Yanli (2)
Author affiliation:(1) Department of Information and Science, Xi'an University of Technology, Xi'an, China; (2) State Key Laboratory of Soil-Plant-Machine System, Chinese Academy of Agricultural Mechanization Sciences, Beijing, China
Corresponding author:Zhao, Bo
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:257-262
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Field weed is the big enemy of agricultural production, and also is one of the key problems that blocked the crop growth in Chinese agriculture. Accurate positioning weeds and realizing the variable precision applying pesticide or herbicide are particularly important. To solve various field weeds positioning difficult problems, a multi-feature based weed reverse positioning method was proposed. By taking the field crops as the research object, the multi-objective weed positioning issue was transformed into single objective crop recognition problem. Firstly, seven moment invariants and eight shape feature parameters were extracted from many of the individual soybean crop leaves, and the mean value of moment invariants and shape features were taken as standard soybean leave feature value. Secondly, after a series of image preprocessing such as image segmentation, regional feature match and connected component analysis, multi-feature recognition method with HU invariant moments and shape features of crops were utilized to accurately locate each crop plant. Finally, based on color feature, the green plants outside of the crops region were treated as weeds. Furthermore, a small weed positioning device was designed based on this method, which was applied to wide pesticide spraying machine. Field experiment results showed that weed recognition accuracy of this system for weed in soybean field was more than 90% when the spraying machine working speed was 5 km/h, hence weed positioning and pesticide accurate spraying problems could be well settled. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:24
Main heading:Crops
Controlled terms:Agricultural machinery - Agriculture - Image segmentation - Pesticides - Plants (botany)
Uncontrolled terms:Invariant moment - Multi features - Reverse positioning - Shape features - Weed
Classification code:461.9 Biology - 741.1 Light/Optics - 803 Chemical Agents and Basic Industrial Chemicals - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
DOI:10.6041/j.issn.1000-1298.2015.06.037
Database:Compendex
<RECORD 13>
Accession number:20152801011273
Title:Dynamic modeling based on POE and non-singular terminal sliding mode control
Authors:Chen, Qingcheng (1); Zhu, Shiqiang (1); Mittal, Rajat (2); Zhang, Xuequn (1)
Author affiliation:(1) State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou, China; (2) Manipal Institute of Technology, Manipal University, Karnataka, India
Corresponding author:Zhu, Shiqiang
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:310-318
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:To compact the dynamic analysis and improve the computation efficiency, the advantages of Kane's equations and the product of exponential (POE) formulas were combined based on screw theory to propose a new effective dynamic modeling of robot manipulator with explicit geometric significance, and based on this dynamic model, a non-singular terminal sliding mode control was presented to achieve better performance. The velocity Jacobian matrix was addressed in the product of exponential form by introducing the screw theory, and the partial velocity of Kane's equations was selected specifically from the suitable velocity Jacobian matrix. Then a dynamic modeling example based on Kane's equations and screw theory was established, which led to be less complicated compared with other typically dynamic methods. With the proposed dynamic equations of serial robot manipulator, a fast non-singular terminal sliding mode (FNTSM) control was presented by introducing an improved fast non-singular terminal sliding mode surface, which was designed to ensure the fast convergence in global system state whether it was near to equilibrium or far away from the equilibrium. Then the stability analysis of the proposed method was performed by using Lyapunov stability theory. Finally, comparative experiments were implemented to demonstrate the effectiveness and robustness of the proposed approach. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:20
Main heading:Sliding mode control
Controlled terms:Computation theory - Dynamic models - Flexible manipulators - Industrial robots - Jacobian matrices - Manipulators - Matrix algebra - Modular robots - Robot applications - Screws
Uncontrolled terms:Comparative experiments - Computation efficiency - Kane's equation - Lyapunov stability theory - Non-singular terminal sliding mode controls - Non-singular terminal sliding modes - Product of exponential - Stability analysis
Classification code:605 Small Tools and Hardware - 731 Automatic Control Principles and Applications - 921 Mathematics - 921.1 Algebra
DOI:10.6041/j.issn.1000-1298.2015.06.045
Database:Compendex
<RECORD 14>
Accession number:20152801011269
Title:Urea decomposition efficiency of diesel engine SCR system
Authors:Ma, Junyan (1); Li, Jun (1); Qu, Dawei (1); Sa, Zhancai (1); Liu, Shaohua (1)
Author affiliation:(1) State Key Laboratory of Automotive Simulation and Control, Jilin University, Changchun, China
Corresponding author:Qu, Dawei
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:282-286 and 309
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to perfect the work efficiency evaluation system of diesel SCR system and improve the work efficiency of SCR system, the theoretical urea decomposition efficiency calculation method of diesel engine SCR system was proposed. The urea decomposition efficiency, amount of leakage of NH<inf>3</inf> and NO<inf>x</inf> conversion efficiency of SCR system for diesel engine were investigated on an engine test bench, the influence of space velocity, NH<inf>3</inf>/NO ratio and SCR temperatures were analyzed. Experiment results showed that the changing trend of NO<inf>x</inf> conversion efficiency and urea decomposition efficiency was basically the same. In the catalyst activation temperature range, the urea decomposition efficiency was above 90%; with the increase of space velocity, the urea decomposition efficiency was increased first and then decreased. NH<inf>3</inf>/NO ratio was 1 with high NO<inf>x</inf> conversion efficiency, but the amount of leakage of NH<inf>3</inf> was exceeded the limit value. NH<inf>3</inf>/NO ratio had little effect on the urea decomposition efficiency, and it was increased with the amount of leakage of NH<inf>3</inf> increasing. When the exhaust gas temperature was raised, the urea decomposition efficiency increased. The space velocity and exhaust gas temperature were the most important factors influencing the urea decomposition efficiency, the level of urea decomposition efficiency was the comprehensive effect of both. Through the study on the factors affecting the decomposition efficiency of urea, to reduce the deposition of urea in the exhaust pipe and improve the removal efficiency of NO<inf>x</inf>. The proposed calculation method can exhibit a trend of urea decomposition efficiency and provide a basis for improving the work efficiency of SCR system. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:13
Main heading:Efficiency
Controlled terms:Conversion efficiency - Diesel engines - Engines - Gases - Metabolism - Selective catalytic reduction - Urea
Uncontrolled terms:Catalyst activation - Comprehensive effect - Decomposition efficiency - Engine test benches - Exhaust gas temperatures - Influencing factors - Removal efficiencies - Urea decomposition
Classification code:451.2 Air Pollution Control - 461.9 Biology - 525.5 Energy Conversion Issues - 612 Engines - 612.2 Diesel Engines - 804.1 Organic Compounds - 913.1 Production Engineering - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.6041/j.issn.1000-1298.2015.06.041
Database:Compendex
<RECORD 15>
Accession number:20152801010859
Title:Interface tracking simulation of immiscible two-phase flow in liquid-liquid dispersion atomization system
Authors:Liang, Kunfeng (1); Jia, Xueying (1); Gao, Chunyan (1); Yuan, Zhulin (2)
Author affiliation:(1) Henan Engineering Laboratory of High Efficiency Heat Exchange and Thermal System Energy Saving Technology, Henan University of Science and Technology, Luoyang, China; (2) College of Energy and Environment, Southeast University, Nanjing, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:363-371
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Simulating the movement, deformation and break-up of immiscible two-phase flow interface was complex and difficult in the liquid-liquid dispersion atomization system. Based on the volume of fraction (VOF) with role of surface tension and interface reconstruction, a model of tracking the immiscible liquid-liquid interface was built with two modes of large and small jet flow rates. The change of oil-water interface was tracked in the process of liquid-liquid dispersion atomization, the micro characteristics of jet break-up and drop formation and growth were simulated, and the mechanism of influence of Re, Ca and Bo criterion numbers on jet break-up and drop formation was also discussed. The results showed that the process of liquid-liquid dispersion atomization can be simulated by the interface tracking model set-up under different jet flow rates, but the simulation capability was short of tracking the process of small scale vortex break-up. Under different modes of drop formation, jet break-up was characterized by randomness, and enhanced with increase of jet flow rate; small droplets were formatted by the volatility and instability of two phases' interface. Under the modes of drop formation of trickling and laminar jet, the shape of drop, jet surface and the section of jet break-up were mainly affected by the variation of Re, Ca and Bo criterion numbers, however, for the mode of drop formation of turbulent motion jet, these criterion numbers mainly influenced the extent of jet break-up and drop size. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:22
Main heading:Two phase flow
Controlled terms:Atomization - Calcium - Computer simulation - Dispersions - Drop formation - Drops - Flow rate - Jets - Liquids - Phase interfaces
Uncontrolled terms:Immiscible two-phase flows - Interface reconstruction - Interface tracking - Liquid-liquid dispersions - Liquid-liquids - Micro characteristics - Oil water interfaces - Small-scale vortices
Classification code:549.2 Alkaline Earth Metals - 631 Fluid Flow - 631.1 Fluid Flow, General - 723.5 Computer Applications - 802.3 Chemical Operations - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2015.06.052
Database:Compendex
<RECORD 16>
Accession number:20152801011233
Title:Design and experiment of profiling elastic press roller
Authors:Jia, Honglei (1); Wang, Wenjun (1); Zhuang, Jian (1); Luo, Xiaofeng (1); Yao, Pengfei (1); Li, Yang (1)
Author affiliation:(1) Key Laboratory of Bionics Engineering, Ministry of Education, Jilin University, Changchun, China; (2) College of Biological and Agricultural Engineering, Jilin University, Changchun, China
Corresponding author:Zhuang, Jian
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:28-34 and 83
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Considering the deficiencies in uneven soil compaction and the too long vertical size that exists in the soybean tillage sowing machine during conservation tillage, the profiling elastic press roller which adopts the elastic spoke structure was designed. The main structure parameters of the press roller were determined through theoretical analysis, which means diameter D of 450 mm, breadth B of 210 mm and number of spokes n of 12. The work process of the roller was simulated by using the ADAMS software, at the same time, orthogonal tests of L<inf>9</inf>(3<sup>4</sup>) were performed in an indoor soil bin with moisture content (dry basis) of 20%. The effects of spring stiffness coefficient (k), total loads (F), operation speed (v) and soil compactness (P) on pressure fluctuation were determined. The optimum ranges of each factor were determined through the ADAMS motion simulation. The results of orthogonal tests showed the primacy sequence of the experiment factors were total loads, spring stiffness coefficient, soil compactness, the operation speed, and optimal levels of the experiment factors were F of 800 N, k of 5 N/mm, P of 15 kPa and v of 0.5 m/s. The simulation results are in good agreement with the experimental results in the pressure fluctuations. Under the condition of a certain inclination angle on the ridge surface, the profiling elastic press roller can better ensure uniformity of soil compaction than that of conventional roller. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:14
Main heading:Presses (machine tools)
Controlled terms:Agricultural machinery - Agriculture - Compaction - Design - Experiments - Rollers (machine components) - Software testing - Soil conservation - Soil mechanics - Soils - Stiffness - Structure (composition)
Uncontrolled terms:Conservation tillage - Inclination angles - Motion simulations - Press rollers - Pressure fluctuation - Simulation - Soil compactness - Spring stiffness
Classification code:408 Structural Design - 483.1 Soils and Soil Mechanics - 536.1 Powder Metallurgy Operations - 601.2 Machine Components - 603.1 Machine Tools, General - 723.5 Computer Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment - 901.3 Engineering Research - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2015.06.005
Database:Compendex
<RECORD 17>
Accession number:20152801011235
Title:Design of steering mechanism with adjustable wheel track
Authors:Liu, Pingyi (1); Wang, Zhenjie (1); Li, Haitao (1); Song, Yingjie (1); Wei, Wenjun (1); Zhang, Shaoying (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:44-48 and 120
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The mechanical work such as weeding, spraying and fertilization requires the chassis should move along the crops' row spacing. Since the row spacing of different crops is various and the row spacing of the same crop in different regions or by different planted methods are also not uniform, there are some problems such as poor flexibility, difficult passing ability, and tendency to destroy the crops when the existing agricultural vehicles running. So the agricultural chassis' wheel track should be adjustable basing on the different crop spacings, during which the steering must be difficult. At present, steering has been solved by hydraulic drive, servo control the turning wheel, or servo motor control the turning wheel, which are more complicated. According to the demand for the chassis' adjustable wheel track varying with different row spacings, the linkage principle of wheel track and steering was researched. Based on the Ackerman steering and parallelogram mechanism, the steering mechanism with adjustable wheel track was proposed in which the wheel track adjustment and steering can be completed independently and simultaneously, and the calculation method of key parameters and steering error were ascertained. A kind of agricultural chassis with adjustable wheel track was designed which included steering mechanism with adjustable wheel track on front bridge, adjustable wheel track mechanism and driving system on rear bridge. Basing on the characteristic of mechanism movement and the criterion of mechanical design, considering the present related chassis and the crop planting mode of China, the key parameters of the chassis has been determined. And the key parameters of steering mechanism with adjustable wheel track on front bridge were determined and optimized by taking minimum wheel track as basic wheel track. The steering error calculation results in different wheel tracks showed that the chassis' adjustable wheel track and steering performance could meet the agricultural needs. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:15
Main heading:Wheels
Controlled terms:Agriculture - Automobile steering equipment - Bridges - Chassis - Crops - Hydraulic drives - Mechanisms
Uncontrolled terms:Agricultural vehicles - Mechanical design - Mechanical work - Parallelogram mechanisms - Servo motor control - Steering mechanisms - Steering performance - Wheel track
Classification code:401.1 Bridges - 601.2 Machine Components - 601.3 Mechanisms - 632.2 Hydraulic Equipment and Machinery - 663.2 Heavy Duty Motor Vehicle Components - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products
DOI:10.6041/j.issn.1000-1298.2015.06.007
Database:Compendex
<RECORD 18>
Accession number:20152801011276
Title:Transverse separation of d-type binary dispersed granular materials with rolling regime in cylinder drum
Authors:Chen, Hui (1); Zhao, Xianqiong (1); Liu, Yilun (1); Xiao, Yougang (2); Liu, Ying (3)
Author affiliation:(1) State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha, China; (2) College of Traffic and Transportation Engineering, Central South University, Changsha, China; (3) School of Architecture and Art, Central South University, Changsha, China
Corresponding author:Liu, Yilun
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:334-340
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Taking granular materials composed of wood particles and clay particles as sample, the rolling motion and separation of density-type binary dispersed granular materials within a cylinder were simulated by using discrete element method. Mixing index of materials was defined by using contact-number between particles, and then transverse separation process was quantitatively investigated by using Hong's theory-the mechanism of competition between percolation and condensation. The results showed that material bed was composed of active layer and passive layer in radial section, where separation between particles was occurred in the active layer. Condensation mechanism, which was caused by density differences between wood particles and clay particles, made the material bed form a moon-pattern separation form. Then wood particles dispersed to the drum wall and clay particles gathered to the center of bed. Percolation mechanism can be introduced by configuring the radios of wood particle and clay particle. The separation could be avoided when percolation effect and condensation effect were balanced each other. The addition of percolation mechanism was not affected by the size of cylinder drum. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:22
Main heading:Particles (particulate matter)
Controlled terms:Bins - Condensation - Cylinders (shapes) - Finite difference method - Granular materials - Percolation (solid state) - Rolling - Separation - Solvents - Wood
Uncontrolled terms:Clay particles - Condensation effects - Density difference - Passive layer - Percolation effects - Rolling motion - Separation process - Wood particles
Classification code:408.2 Structural Members and Shapes - 535.1 Metal Rolling - 694.4 Storage - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 811.2 Wood and Wood Products - 921.6 Numerical Methods - 933 Solid State Physics - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2015.06.048
Database:Compendex
<RECORD 19>
Accession number:20152801011266
Title:Calculation of light distribution of apple tree canopy based on color characteristics of 3D point cloud
Authors:Ma, Xiaodan (1); Guo, Cailing (1); Zhang, Xue (1); Ma, Li (1); Zhang, Lijiao (1); Liu, Gang (1)
Author affiliation:(1) Key Laboratory for Modern Precision Agriculture System Integration Research, Ministry of Education, China Agricultural University, Beijing, China; (2) College of Information Technology, Heilongjiang Bayi Agricultural University, Daqing, China
Corresponding author:Liu, Gang
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:263-268
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Study on light distribution of apple tree canopy is one of the important ways to optimize type of fruit trees and improve potential production. The reasonable and effective use of light energy and optimization of light distribution within fruit tree canopy have vital significance for the formation of fruit tree growth and fruit quality. Calculation method of light distribution of free spindle apple canopy was carried out. In recent years, there were several researches on light distribution of plant canopy on the basis of three dimensional morphology of plant canopy by using mathematical simulation methods which could not express the real light distribution. In order to reveal real light distribution rule of canopy intelligently and efficiently, apple trees of spindle shape were selected as research objects, and based on the correlation that the target image color changed with the light intensity. Firstly, 3D point cloud of apple tree canopy in leaf curtain stability period was captured by Trimble TX5 laser scanner; secondly, according to the actual canopy division method, color information of different areas in 3D canopy space was extracted; thirdly, aiming at the shortcomings of complexity, fuzziness and indescribability by precise and quantitative symbols under natural environment, the fuzzy neural network was constructed to predict light distribution with color characteristic as input and relative light intensity as output. The experimental results showed that the precision of the proposed method had good feasibility, the prediction accuracy was 80.57%. The result of this study will provide theoretical basis for scientific pruning to get the best light distribution. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:17
Main heading:Light
Controlled terms:Color - Complex networks - Distributed computer systems - Forestry - Fruits - Fuzzy inference - Fuzzy logic - Fuzzy neural networks - Mathematical morphology - Orchards
Uncontrolled terms:3D point cloud - Apple tree canopies - Color characteristics - Light distribution - Mathematical simulations - Natural environments - Potential production - Three dimensional morphology
Classification code:721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 722 Computer Systems and Equipment - 722.4 Digital Computers and Systems - 723.4 Artificial Intelligence - 741.1 Light/Optics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2015.06.038
Database:Compendex
<RECORD 20>
Accession number:20152801011256
Title:Effects of enzymatic pretreatment straw wastes on its characteristics of anaerobic digestion for biogas production
Authors:Deng, Yuanfang (1); Qiu, Ling (2); Huang, Hui (1); Dai, Benlin (1); Wang, Yixian (4); Xu, Jiming (1)
Author affiliation:(1) Jiangsu Key Laboratory for Biomass-Based Energy and Enzyme Technology, Huaiyin Normal University, Huaian, China; (2) College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling; Shaanxi, China; (3) Jiangsu Collaborative Innovation Center of Regional Modern Agriculture & Environmental Protection, Huaiyin Normal University, Huaian, China; (4) Commission of Agriculture of Huaian, Huaian, China
Corresponding author:Qiu, Ling
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:201-206
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A biological pretreatment with Trichoderma reesei culture was used to pretreat straw wastes (i.e. rice straw, wheat stalk and their mixture) at ambient temperature (30±1) to improve their biodegradability and anaerobic biogas production. The initial Trichoderma reesei spores dose was 200 μL, it had twice expanding training, and the pretreatment time of 72 h was appropriate for biological pretreatment. These treatment conditions resulted in more total biogas yield, methane yield and shorter technical digestion time compared with the untreated sample. The total gas production from pretreated straw wastes reached the maximum of 14 555, 15 103 and 17 130 mL for rice straw, wheat straw and their mixture, respectively. The average methane concentration levels were at 48.2%, 45.4% and 47.8%, respectively. The highest methane concentrations were at 60.5%, 66.1% and 66.8%, respectively. The average methane concentrations were increased by 205.1%, 213.1% and 214.5% compared with the untreated sample. The values of pH, VFA were located in normal range. The average daily degradation values of COD reached 522.23, 542.50 and 668.72 g/d and TS degradative rates were 172.84, 183.12 and 205.54 mL/g, respectively. The digestion time DT<inf>90</inf> for pretreated straw waste which contained a mixture of rice straw and wheat stalk was calculated. The significant reduction of digestion time indicated that the straw had become more accessible and readily biodegradable after biological pretreatment. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:21
Main heading:Anaerobic digestion
Controlled terms:Biodegradation - Biogas - Methanation - Methane - Mixtures - Straw
Uncontrolled terms:Biogas production - Biological pre-treatment - Enzymatic pretreatment - Enzyme pretreatment - Gas productions - Methane concentrations - Treatment conditions - Trichoderma reesei
Classification code:522 Gas Fuels - 801.2 Biochemistry - 802.2 Chemical Reactions - 802.3 Chemical Operations - 821.5 Agricultural Wastes
DOI:10.6041/j.issn.1000-1298.2015.06.028
Database:Compendex
<RECORD 21>
Accession number:20152801011272
Title:Gearshift control of direct-drive AMT gearshift system based on inverse system method
Authors:Lin, Shusen (1); Jiao, Weidong (1); Cao, Zhenxin (1); Wu, Jiangmiao (1); Zhang, Lanchun (2)
Author affiliation:(1) College of Engineering, Zhejiang Normal University, Jinhua, China; (2) School of Automobile and Traffic Engineering, Jiangsu University of Technology, Changzhou, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:303-309
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:To improve the shift performance stability of the direct-drive automated manual transmission (AMT) gearshift system, inverse system method (ISM) was introduced according to the characteristics of 2-DOF electromagnetic actuator. The structure and working principle of the actuator were described, and the analysis of the mathematical model indicated that the parameters of the actuator affected each other. Static characteristics experiments proved that the output characteristics were nonlinear. The reversibility of the system was analyzed and ISM was adopted to build the pseudo-linear system, and the state feedback controller was designed according to the linear system theory. Extended state observer (ESO) was added to weaken the influence of time varying friction force to the stability of the output characteristics. The simulation and experiment results indicate that controlled by the ISM-ESO controller, the gearshift performance is robust to variable parameters. The precision of displacement control is better. The stability of the output characteristics is improved. Based on the inverse system method, the gearshift performance of the direct-drive automated manual transmission is relatively excellent, and it is conducive to improve the competitiveness of AMT. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:16
Main heading:Inverse problems
Controlled terms:Actuators - Automation - Controllers - Feedback - Friction - Gears - Linear systems - Speed control - State estimation - State feedback - Transmissions
Uncontrolled terms:Automated manual transmission - Direct drive - Extended state observer - Gearshift control - Inverse system
Classification code:601.2 Machine Components - 602.2 Mechanical Transmissions - 731 Automatic Control Principles and Applications - 732 Control Devices - 732.1 Control Equipment - 921 Mathematics - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2015.06.044
Database:Compendex
<RECORD 22>
Accession number:20152801011262
Title:Evaluation of steviol glycosides sweetness taste by electronic tongue
Authors:Yang, Yang (1); Shen, Cheng (2); Sang, Yue (2); Li, Xianzhi (2); Wu, Jihong (2); Ni, Yuanying (2)
Author affiliation:(1) Cloud Live Technology Group Co., Ltd., Beijing, China; (2) National Engineering Research Center for Fruits and Vegetables Processing, China Agricultural University, Beijing, China
Corresponding author:Ni, Yuanying
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:239-243 and 281
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:There is an urgent need in the food and beverages industry for evaluation of the sweetness taste by using a rapid and objective method. An electronic tongue was used to evaluate sweetness taste and compare different steviol glycosides (different compositions of rebaudioside A: RA95, RA97, RA99, RA/RB(90/10), RA/RD(90/7)). Five RA samples and sucrose used as a reference were analyzed by the electronic tongue and sensory panels. Sensory analysis demonstrated that the RA samples (0.2~0.8 g/L) were 90~220 times sweeter than that of sucrose (0.03~0.09 g/mL). The data obtained by electronic tongue was analyzed by principal component analysis (PCA). The extinction time of all RA samples ranged from 10 s to more than 60 s, and RA at 1.2 g/L exhibited intense bitter taste. Five RA samples were successfully discriminated on the PCA score plot. Compared with sucrose at different concentrations, the intensity of sweetness taste of RA samples was ranked as: RA/RD(90/7)>RA95>RA/RB(90/10) and RA99>RA97>RA95. Based on euclidean distance on the PCA score plot, RA99 was revealed more similar taste than that of RA95 and RA97. The results showed that the electronic tongue analysis might be a useful method to complement sensory panels in evaluation of sweetness. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:25
Main heading:Electronic tongues
Controlled terms:Glycosides - Principal component analysis - Sensory analysis - Sugar (sucrose) - Sugars
Uncontrolled terms:Euclidean distance - Extinction time - Objective methods - Rebaudioside-A - Sensory evaluation - Sensory panels - Steviol glycosides - Sweetness
Classification code:801 Chemistry - 804.1 Organic Compounds - 822.3 Food Products - 922.2 Mathematical Statistics
DOI:10.6041/j.issn.1000-1298.2015.06.034
Database:Compendex
<RECORD 23>
Accession number:20152801011240
Title:Optimization of impeller meridional shape based on radial basis neural network
Authors:Wang, Wenjie (1); Pei, Ji (1); Yuan, Shouqi (1); Zhang, Jinfeng (1); Xu, Changzheng (2); Zhang, Fan (1)
Author affiliation:(1) National Research Center of Pumps, Jiangsu University, Zhenjiang, China; (2) Yixing Unite Machinery Co., Ltd., Wuxi, China
Corresponding author:Yuan, Shouqi
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:78-83
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:To improve the efficiency of residual heat removal pump, 35 impellers, whose design variables are the radius of shroud arc, radius of hub arc, angle of shroud and angle of hub, were designed by Latin hypercube sampling method. 3D steady simulation was conducted to get the efficiency under designed flow rate by ANSYS CFX 14.5 software. A radial basis neural network was used to build the approximation model between efficiency and design variables. Finally, the best combination of the design variables was obtained by solving the approximation model with genetic algorithm. The results showed that performance curve simulated by CFD had a good agreement with that of experiment. The deviations of efficiency and head between numerical result and experimental result were -2.1% and -3.7%, respectively. Compared the efficiency predicted by CFD with that predicted by radial basis neural network, the deviation was only 0.02%, thus the radial basis neural network can predict the efficiency under design condition accurately. The efficiency of the optimal pump was 76.75% and the optimization made an increase in efficiency by a percentage of 6.18. The optimization improved the velocity and turbulence kinetic energy distributions in the impeller. The vortexes disappeared and the velocity became uniform at the shroud. Thus, the optimization process for the impeller meridional shape was practical. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:18
Main heading:Impellers
Controlled terms:Approximation algorithms - Computational fluid dynamics - Computer software - Design - Genetic algorithms - Kinetic energy - Kinetics - Optimization - Pumps
Uncontrolled terms:Approximation model - Latin hypercube sampling methods - Meridional shape - Numerical results - Performance curve - Radial basis neural networks - Residual heat removal pumps - Turbulence kinetic energy
Classification code:408 Structural Design - 601.2 Machine Components - 618.2 Pumps - 723 Computer Software, Data Handling and Applications - 921 Mathematics - 921.5 Optimization Techniques - 931 Classical Physics; Quantum Theory; Relativity - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2015.06.012
Database:Compendex
<RECORD 24>
Accession number:20152801011237
Title:Numerical investigation of internal flow mechanisms of siphon outlet passage in pumping system
Authors:Yang, Fan (1); Liu, Chao (1); Sun, Dandan (2); Xie, Rongsheng (1); Zhang, Liping (2)
Author affiliation:(1) School of Hydraulic, Energy and Power Engineering, Yangzhou University, Yangzhou, China; (2) Institute of Water Conservancy Works Design of Xuzhou, Xuzhou, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:60-65 and 91
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to analyze the flow influence mechanism of axial-flow pump on the siphon outlet passage, the three-dimensional internal flow of an axial-flow pumping system with siphon outlet passage was simulated based on CFD method under different running conditions. The relationship between guide vane outlet velocity circulation and flow rate had obvious influence on hydraulic loss and internal flow field of siphon outlet passage. The flow field characteristics of siphon outlet passage were analyzed qualitatively, and the mathematical relationship between them was analyzed quantitatively. The research results indicated that there was great difference between internal flow field of siphon outlet passage under different running conditions, and the hydraulic loss of siphon outlet passage was mainly concentrated on flow passage before hump section. The average value of velocity-weighted average swirl angle was 52.34°, and it had small fluctuation in the flow coefficient range of 0.35~0.70 for hump section. With the increase of flow coefficient, the axial velocity distribution uniformity of hump section increased gradually, while the guide vane outlet velocity circulation decreased firstly and then increased, and the minimum velocity circulation was in the high efficiency area. Guide vane outlet velocity circulation made the relationship of hydraulic loss of siphon outlet passage and flow rate more complicated, and there was no quadratic regression relationship between hydraulic loss and flow rate. These study results were available reference for design optimization of siphon outlet passage. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:12
Main heading:Computational fluid dynamics
Controlled terms:Axial flow - Computer simulation - Flow fields - Flow rate - Pumping plants - Pumps - Siphons - Velocity - Velocity distribution
Uncontrolled terms:Axial flow pump - Axial-velocity distribution - Flow field characteristics - Hydraulic performance - Mathematical relationship - Numerical investigations - Quadratic regression - Three dimensional internal flow
Classification code:446 Waterworks - 618.2 Pumps - 631 Fluid Flow - 631.1 Fluid Flow, General - 723.5 Computer Applications - 931.1 Mechanics - 931.3 Atomic and Molecular Physics
DOI:10.6041/j.issn.1000-1298.2015.06.009
Database:Compendex
<RECORD 25>
Accession number:20152801011264
Title:Identification of pesticide residues on mulberry leaves based on hyperspectral imaging
Authors:Sun, Jun (1); Zhang, Meixia (2); Mao, Hanping (1); Li, Zhengming (2); Yang, Ning (1); Wu, Xiaohong (2)
Author affiliation:(1) Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education, Jiangsu University, Zhenjiang, China; (2) School of Electrical and Information Engineering, Jiangsu University, Zhenjiang, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:251-256
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A non-destructive testing method was studied to rapidly and accurately detect pesticide residues on mulberry leaves. Six groups of mulberry leaves were chosen as experimental samples, which contained pesticide residues of dichlorvos, chlorpyrifos, acephate, dimethoate and phoxim as the first to fifth groups, respectively, and the sixth group without pesticide residues was taken as control. Hyperspectral images of samples in 390~1050 nm were acquired by hyperspectral imaging devices. The region of interest from hyperspectral image was selected, and ten characteristic wavelengths, which were 452.51, 469.88, 517.28, 539.85, 578.92, 643.72, 727.24, 758.34, 785.67 and 819.67 nm, were selected by the successive projections algorithm (SPA). Based on RBF kernel function of SVM and 10 fold cross-validation methods, the detection models of pesticide residues on mulberry leaves were established. The impacts of three parameter optimization algorithms (grid search, genetic algorithm and particle swarm optimization) on the model performance were discussed. The results showed that performance of SVM model by using grid search was the optimal one, and its cross-validation accuracy was 63.89% and forecast accuracy was 78.33%. In order to further enhance the classification performance of the model, the adaptive algorithm (Adaboost) was introduced into the SVM model, and Ada-SVM algorithm was used to build classification model, which can detect pesticide residues on mulberry leaves and identify the kinds of pesticide residues. The results showed that the prediction accuracy of Ada-SVM model reached 97.78%, which was increased by 19.45% compared with the original SVM model. Therefore, hyperspectral imaging technology combined with Ada-SVM algorithm can accurately identify the pesticide residues on mulberry leaves. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:25
Main heading:Pesticides
Controlled terms:Adaptive algorithms - Adaptive boosting - Algorithms - Genetic algorithms - Image segmentation - Imaging techniques - Independent component analysis - Nondestructive examination - Optimization - Particle swarm optimization (PSO) - Plants (botany) - Spectroscopy - Support vector machines - Testing
Uncontrolled terms:Classification performance - Genetic algorithm and particle swarm optimizations - Hyperspectral Imaging - Hyperspectral imaging technologies - Mulberry leaves - Nondestructive testing method - Pesticide residue - Successive projections algorithms (SPA)
Classification code:421 Strength of Building Materials; Mechanical Properties - 423.2 Non Mechanical Properties of Building Materials: Test Methods - 461.9 Biology - 723 Computer Software, Data Handling and Applications - 741 Light, Optics and Optical Devices - 741.1 Light/Optics - 746 Imaging Techniques - 801 Chemistry - 803 Chemical Agents and Basic Industrial Chemicals - 921.5 Optimization Techniques
DOI:10.6041/j.issn.1000-1298.2015.06.036
Database:Compendex
<RECORD 26>
Accession number:20152801011275
Title:High-pressure bi-directional oval gear tiny-flow meter
Authors:Ding, Fan (1); Deng, Minsheng (1); Liu, Shuo (1); Ding, Chuan (1); Man, Zaipeng (1); Li, Qipeng (1)
Author affiliation:(1) State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:327-333
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:With the popularity of high pressure hydraulic system and the increasing requirements for the efficient and automatic control, the measure of tiny flow under the high pressure condition is more and more important. And the relevant research also has great importance for the development of domestic flow meters industry. A bi-directional oval gear flowmeter used for the measurement of tiny flow under high pressure condition was presented, which used a pair of low eccentricity oval gears as the core components and used hall sensors for the non-contact signal-detection. The designed flowmeter was with a lower displacement in order to measure tiny flow. A fully closed measurement volume was built so that the flowmeter can endure high pressure. A complete CAD model was established for the CNC machining of oval gear in order to ensure the high accuracy, including the pitch curve equation of oval gear and the solution of tooth profile based on the converted method. In order to validate the design and research the flowmeter's metrological characteristics, experiments on a prototype fabricated were performed. And a modification method of flow coefficient was proposed on the basis of least square method. The experiments results showed that the maximal pressure loss was 0.46 MPa at flow rate of 3 L/min, and the flowmeter was with a relative error less than 1% over a flow rate range of 0.03~3 L/min, and 0.5% over a flow rate range of 0.05~3 L/min. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:13
Main heading:Flowmeters
Controlled terms:Automation - Computer aided design - Flow measurement - Flow rate - Gears - Hall effect transducers - Hydraulic equipment - Least squares approximations
Uncontrolled terms:High pressure - High-accuracy - Low eccentricity - Oval gears - Tiny flow
Classification code:601.2 Machine Components - 631 Fluid Flow - 631.1 Fluid Flow, General - 632.2 Hydraulic Equipment and Machinery - 714 Electronic Components and Tubes - 723.5 Computer Applications - 731 Automatic Control Principles and Applications - 732 Control Devices - 921.6 Numerical Methods - 943.1 Mechanical Instruments - 943.2 Mechanical Variables Measurements
DOI:10.6041/j.issn.1000-1298.2015.06.047
Database:Compendex
<RECORD 27>
Accession number:20152801011263
Title:Estimation model of nitrogen content for citrus leaves by spectral technology based on manifold learning algorithm
Authors:Yue, Xuejun (1); Quan, Dongping (1); Hong, Tiansheng (2); Liu, Yongxin (1); Wu, Muchun (2); Duan, Jieli (2)
Author affiliation:(1) College of Electronic Engineering, South China Agricultural University, Guangzhou, China; (2) College of Engineering, South China Agricultural University, Guangzhou, China
Corresponding author:Hong, Tiansheng
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:244-250
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Traditional methods of obtaining nitrogen content of citrus leaves are time-consuming, and the process is cumbersome and harmful to citrus leaves, which need proficient experiment techniques and amounts of instruments, equipment and chemical reagents. According to the high dimensionality and redundancy of origin spectral reflectance, a nitrogen content obtaining method of citrus leaves was provided based on manifold learning algorithm which was applied to the high-dimensional spectral vectors for dimension reduction and feature extraction. During four different growth stages, corresponding to germination, stability, bloom and picking stages, spectral reflectance of citrus leaves were measured by the ASD FieldSpec 3 spectrometer, respectively, and at the same time, nitrogen content of citrus leaves was obtained by using Kjeldahl method. For data processing, firstly the parameter combination of wavelet denoising which was used to the high-frequency noise removal was optimized through orthogonal test, and then the principal component analysis (PCA), multidimensional scaling (MDS), locally-linear embedding (LLE), isometric mapping (Isomap) and laplacian eigenmaps (LE) manifold learning algorithms were applied to extract features of original spectrum and denoised spectrum. Finally, the five corresponding support vector regression (SVR) prediction models of nitrogen content for citrus leaves were established based on their features. Experiment results reveal that the five manifold learning algorithms can be effectively used to predict nitrogen content of citrus leaves, which provides theoretical basis for obtaining nitrogen content of citrus leaves rapidly and non-destructively, as well as in growth monitoring and variable-rate fertilization. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:18
Main heading:Learning algorithms
Controlled terms:Algorithms - Chemical equipment - Data handling - Feature extraction - Nitrogen - Principal component analysis - Reflection
Uncontrolled terms:Citrus leaves - Manifold learning - Manifold learning algorithm - Multi-dimensional scaling - Nitrogen content - Spectrum - Support vector regression (SVR) - Variable rate fertilization
Classification code:711 Electromagnetic Waves - 716 Telecommunication; Radar, Radio and Television - 723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 802.1 Chemical Plants and Equipment - 804 Chemical Products Generally - 922.2 Mathematical Statistics
DOI:10.6041/j.issn.1000-1298.2015.06.035
Database:Compendex
<RECORD 28>
Accession number:20152801011277
Title:Fast identification of machine tool spindle temperature rise characteristics based on nonlinear prediction
Authors:Feng, Gang (1); Xia, Chenhui (2); Sun, Lei (2); Fu, Jianzhong (2)
Author affiliation:(1) School of Mechanical Engineering, Zhejiang Industry Polytechnic College, Shaoxing, China; (2) School of Mechanical Engineering, Zhejiang University, Hangzhou, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:341-348
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A new method of fast identifying temperature rise characteristics for machine tool spindle was developed. The nonlinear prediction technology based on support vector machine regression can predict the spindle temperature rise curve for a long time by only using a short period of measurement time. The steady-state temperature and thermal equilibrium time can be easily obtained from temperature prediction. The thermal balance test in the vertical machining center was done, and the method was applied under different working conditions. When spindle was running at 5000 r/min with room temperature of 18, the temperature rise of the selected point was identified in 48 min while the time for obtaining the temperature rise curve from start-up of machine tool to temperature steady-state machine tool in practice can reach 400 min. The root mean square error (RMSE) between estimated and measured temperature was 0.1848, and the error between estimated and measured steady-state temperature was 0.0392. The method can greatly shorten thermal balance test duration. The experimental research illustrated that the method of identifying spindle temperature rise characteristics was fit for thermal balance test. It proved that the novel method was effective and feasible. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:20
Main heading:Machine tools
Controlled terms:Forecasting - Mean square error - Support vector machines
Uncontrolled terms:Machine tool spindles - Non-linear predictions - Root mean square errors - Steady-state temperature - Support vector machine regressions - Temperature prediction - Temperature rise - Vertical machining centers
Classification code:603.1 Machine Tools, General - 723 Computer Software, Data Handling and Applications - 731.1 Control Systems - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2015.06.049
Database:Compendex
<RECORD 29>
Accession number:20152801011251
Title:Effects of soil amendments on soil air permeability in film mulched drip irrigation field
Authors:Wang, Weihua (1); Li, Jianbo (1); Zhang, Zhipeng (1); Wang, Quanjiu (2)
Author affiliation:(1) Faculty of Modern Agricultural Engineering, Kunming University of Science and Technology, Kunming, China; (2) Institute of Water Resources and Hydroelectric Engineering, Xi'an University of Technology, Xi'an, China; (3) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling; Shaanxi, China
Corresponding author:Wang, Quanjiu
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:160-167
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A field experiment was conducted in order to evaluate the effects of soil amendments on soil air permeability under plastic mulching condition. The results showed that soil texture kept slight changes after applying soil amendments; however, it resulted in significant decrease of soil bulk density and increase of saturated water content and field capacity. Although plastic sheet mulch was helpful for soil water storage and heat preservation, it prevented air exchange at soil-atmosphere interface which led to decrease of soil air permeability. Meanwhile, soil structure and physical properties were improved through the application of soil amendments, resulting in clear air flow in soil pores, which led to increase of soil air permeability. Furthermore, the improvement of three types of soil amendment on soil air permeability were ranked in the order of phosphogypsum (PG) > polyacrylamide (PAM) > Handilong. As for PAM and Handilong treatments, high application rate had better effect on soil air permeability than that of low application rate. As for PG treatment, the value of soil air permeability under high application rate was 1.12 times as high as that under low application rate, and moderate and low application rates had similar effects on soil air permeability. The results indicated that soil amendments could obviously improve soil air permeability, which certainly provided new methods for improving soil air permeability during field crops growth. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:16
Main heading:Soils
Controlled terms:Air - Air permeability - Associative storage - Crops - Gypsum - Irrigation - Phase interfaces - Plastic sheets - Polyacrylates - Soil moisture
Uncontrolled terms:Film mulching - Heat preservation - Mulched drip irrigations - Phosphogypsum - Polyacrylamide(PAM) - Soil air permeabilities - Soil amendment - Soil water storage
Classification code:412 Concrete - 414 Masonry Materials - 483.1 Soils and Soil Mechanics - 722.1 Data Storage, Equipment and Techniques - 801.4 Physical Chemistry - 804 Chemical Products Generally - 813 Coatings and Finishes - 815.1.1 Organic Polymers - 817.1 Polymer Products - 819.5 Textile Products and Processing - 821.3 Agricultural Methods - 821.4 Agricultural Products
DOI:10.6041/j.issn.1000-1298.2015.06.023
Database:Compendex
<RECORD 30>
Accession number:20152801011255
Title:Effects of combined hydrogen peroxide and liquid ammonia treatment on enzymatic hydrolysis of corn cob
Authors:Zhao, Chao (1); Shao, Qianjun (2); Cao, Yan (1); Ding, Weimin (4); Peng, Hehuan (1)
Author affiliation:(1) School of Engineering, Zhejiang A&F University, Hangzhou, China; (2) National Engineering Research Center for Wood-Based Resource Utilization, Hangzhou, China; (3) Faculty of Mechanical Engineering & Mechanics, Ningbo University, Ningbo, China; (4) College of Engineering, Nanjing Agricultural University, Nanjing, China
Corresponding author:Shao, Qianjun
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:193-200
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:To effectively improve the enzymatic digestibility of carbohydrates in lignocelluloses, the combined hydrogen peroxide and liquid ammonia treatment (H-LAT) was employed as pretreatment for corn cob. The effects of temperature and H<inf>2</inf>O<inf>2</inf> loading on solid recovery, enzymatic digestibility and lignocellulosic structure of corn cob were investigated. The results showed that the H-LAT pretreatment could effectively remove lignin and retain the most of carbohydrate in the corn cob. Enzymatic hydrolysis using cocktail enzymes including cellulase, β-glucosidase and xylanase for 72 h after pretreatment under optimal conditions, the H-LAT pretreatment achieved 85.0% of theoretical sugar yield, and it could produce 593.1 g fermentable monosaccharide per kilogram of dry biomass. Compared with untreated substrates, it was about 3.53-fold in sugars yields for H-LAT treated substrates. X-ray diffraction analysis showed that the crystalline region and amorphous region of corn cob were synchronously decreased; the crystallinity changes were depended on the interaction of the two effects. Infrared spectrum analysis showed that the H-LAT pretreatment effectively broke down cellulose hydrogen bonds, and disrupted ester linkage in lignin-carbohydrate complexes. Meanwhile, lignin molecular structure was partly destructed, and the distribution of lignin produced certain changes. As a result, these changes effectively reduced the biomass recalcitrance of corn cob. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:27
Main heading:Enzymatic hydrolysis
Controlled terms:Ammonia - Carbohydrates - Cellulose - Hydrogen bonds - Hydrogen peroxide - Hydrolysis - Lignin - Liquids - Oxidation - Peroxides - Spectrum analysis - X ray diffraction analysis
Uncontrolled terms:Biomass recalcitrances - Cellulose hydrogen bonds - Corn cob - Effects of temperature - Enzymatic digestibility - Lignin-carbohydrate complex - Liquid ammonia - Pre-Treatment
Classification code:801 Chemistry - 801.4 Physical Chemistry - 802.2 Chemical Reactions - 804.1 Organic Compounds - 804.2 Inorganic Compounds - 815.1.1 Organic Polymers - 921 Mathematics - 931.2 Physical Properties of Gases, Liquids and Solids - 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:10.6041/j.issn.1000-1298.2015.06.027
Database:Compendex
<RECORD 31>
Accession number:20152801011249
Title:Drip irrigation uniformity calculation considering distribution location of clogged emitters
Authors:Niu, Wenquan (1); Zhang, Ruochan (1); Luo, Chunyan (3)
Author affiliation:(1) College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling; Shaanxi, China; (2) Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling; Shaanxi, China; (3) College of Energy and Water Resources, Shenyang Institute of Technology, Shenyang, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:147-152 and 174
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Irrigation uniformity is one of the most important indicators of drip irrigation system, and clogging is perhaps the most common factor which affects the uniformity. In order to evaluate the influence of clogged emitters on the irrigation uniformity and the growth of crops during the operational process of drip irrigation system, the concept and computational method of location distribution uniformity of clogged emitters were set up based on the Christiansen uniformity, and then a new computational method of drip irrigation uniformity was proposed by using the arithmetic mean of the location distribution uniformity of clogged emitters and the flux uniformity of emitters, finally a comparison between several types of computational method of uniformity in a lateral and a subunit was made. The results showed that both the drip irrigation uniformity which considered the location distribution of clogged emitters and the Christiansen uniformity can reflect the influence of the amount of clogged emitter and the level of clogging on irrigation uniformity. In the meanwhile, the proposed method can also reflect the influence of location distribution of clogged emitters on the irrigation uniformity and overcome the weakness of Christiansen uniformity which only considered the influence of flow deviation. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:15
Main heading:Irrigation
Controlled terms:Computational methods - Location
Uncontrolled terms:Arithmetic mean - Clogged emitter - Common factors - Distribution uniformity - Drip irrigation - Drip irrigation systems - Irrigation uniformity - Operational process
Classification code:821.3 Agricultural Methods - 911 Cost and Value Engineering; Industrial Economics - 912 Industrial Engineering and Management - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2015.06.021
Database:Compendex
<RECORD 32>
Accession number:20152801011268
Title:Spray characteristics of an outward-opening gasoline piezoelectric injector
Authors:He, Bangquan (1); Ye, Fei (1)
Author affiliation:(1) State Key Laboratory of Engines, Tianjin University, Tianjin, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:275-281
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The spray characteristics of gasoline, n-butanol and ethanol injected from an outward-opening gasoline piezoelectric injector were investigated with Schlieren and laser Mie scattering techniques in a constant volume vessel. Experimental results showed that the hollow conical spray was composed of numerous tiny jets. The macrostructures of spray were affected by the magnitude of back pressure. With the increase of back pressure, the gap between two adjacent jets was decreased and finally disappeared. In the meantime, the penetration and projected area of spray were sharply reduced. However, the spray cone angel was nearly unchanged with time regardless of the magnitude of back pressure and fuel types. Furthermore, the decline of spray penetration was always larger in horizontal direction than that in vertical direction. But the penetration in horizontal direction was longer than that in vertical direction. The spray penetration in vertical direction for ethanol and n-butanol with relatively higher viscosity was longer than that for gasoline, which was contributed to the vortex formed during injection. The larger the scale of the vortex, the longer the penetration in horizontal direction was. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:19
Main heading:Gasoline
Controlled terms:Alcohols - Brillouin scattering - Direct injection - Ethanol - Light scattering - Piezoelectricity - Vortex flow
Uncontrolled terms:Back pressures - Constant-volume vessel - Macrostructures - Mie scattering - Schlieren method - Spray characteristics - Spray penetration - Vertical direction
Classification code:521 Fuel Combustion and Flame Research - 523 Liquid Fuels - 631.1 Fluid Flow, General - 701.1 Electricity: Basic Concepts and Phenomena - 741.1 Light/Optics - 804.1 Organic Compounds
DOI:10.6041/j.issn.1000-1298.2015.06.040
Database:Compendex
<RECORD 33>
Accession number:20152801011252
Title:Real-time soil moisture measurement method on line scale
Authors:Zhao, Yandong (1); Dong, Xiaochen (1); Li, Ning (1)
Author affiliation:(1) School of Technology, Beijing Forestry University, Beijing, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:168-174
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A real-time soil moisture measurement method on line scale was proposed and a real-time detection of plant root zone soil moisture information sensing system based on frequency domain oscillometry was designed. The system consisted of soil moisture sensor, PVC casing, electric traction system and controller. The sensor was reciprocated in the casing which was dragged by motors, and it can obtain 240 cm real-time soil volumetric water content information. The dynamic response time of sensor was 32 ms, standard deviation of stability test was 0.0061 V, determination coefficient between measured results and TDR was 0.989, and the requirement of the soil moisture measurement was satisfied. The results of field tests showed that the mean squared error compared with that of BD-III soil moisture sensors based on SWR (accuracy of ±2%) which were buried 10 cm apart and paralleled to the sensing system was less than 0.5% when the sensing system was buried under the ground of 30 cm. The measured data can reflect the volumetric water content of plant root zone under different rainfall conditions and verify the effectiveness of the system. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:29
Main heading:Soil moisture
Controlled terms:Dynamic response - Electric traction - Frequency domain analysis - Mean square error - Moisture - Moisture control - Moisture determination - Moisture meters - Social networking (online) - Soil surveys - Soils - Traction control
Uncontrolled terms:Determination coefficients - Electric traction system - Line scale - Measuring - Oscillometry - Soil moisture measurement - Soil volumetric water contents - Volumetric water content
Classification code:408.1 Structural Design, General - 483.1 Soils and Soil Mechanics - 705 Electric Generators and Motors - 723 Computer Software, Data Handling and Applications - 731.1 Control Systems - 731.2 Control System Applications - 801.4 Physical Chemistry - 944.1 Moisture Measuring Instruments - 944.2 Moisture Measurements
DOI:10.6041/j.issn.1000-1298.2015.06.024
Database:Compendex
<RECORD 34>
Accession number:20152801011245
Title:Evaluation of nitrogen and water management in winter wheat-summer maize cropping system in north china plain using RZWQM
Authors:Li, Yan (1); Liu, Haijun (2); Huang, Guanhua (1)
Author affiliation:(1) College of Water Resources & Civil Engineering, China Agricultural University, Beijing, China; (2) College of Water Sciences, Beijing Normal University, Beijing, China
Corresponding author:Huang, Guanhua
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:111-120
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The long-time excessive application of N fertilizer caused detrimental effects on soil and groundwater environment in North China Plain (NCP). Therefore, the reasonable water and N managements are essential for the sustainable agricultural production in this region. A two-year field experiment (2010-2011) was carried out in the wheat-maize rotation cropping field at Tongzhou Experimental Base for Water-saving Irrigation Research (TEB), Chinese Academy of Sciences, Tongzhou District, Beijing, China. The collected data in the experiment was used to calibrate and validate the hydrologic, nitrogen and crop growth components of the root zone water quality model (RZWQM). And the validated RZWQM was used to evaluate N fertilizer and water management practices in wheat-maize rotation cropping system under sprinkler irrigation system in NCP. The validation results showed that the R<inf>MSE</inf> (root mean square errors) and M<inf>RE</inf> (mean relative error) for soil water content ranged from 0.015 cm<sup>3</sup>/cm<sup>3</sup> to 0.026 cm<sup>3</sup>/cm<sup>3</sup> and from -6.66% to 5.83%, respectively. The simulated soil water storage was close to the measured ones. The relative errors (R<inf>E</inf>) of measured and predicted crops yields and N uptakes of winter wheat and maize were generally less than 25%. The RZWQM was used to simulate the dynamics of soil water and nitrogen in the wheat-maize rotation cropping system under different irrigation interval when N application was the same to local N management (330 kg/hm<sup>2</sup>). Results showed that the crop yields were higher, however, NO<inf>3</inf>-N leaching and mean N losses were less at irrigation interval with accumulated pan evaporation of 30~70 mm than those at irrigation interval with pan evaporation of 90~110 mm. Therefore, sprinkler irrigation interval with pan evaporation of 30~70 mm was recommended in wheat-maize rotation system in NCP. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:27
Main heading:Sprinkler systems (irrigation)
Controlled terms:Agriculture - Crops - Digital storage - Errors - Evaporation - Fertilizers - Groundwater - Irrigation - Leaching - Mean square error - Nitrogen - Rotation - Soil moisture - Soils - Water conservation - Water content - Water management - Water quality
Uncontrolled terms:Crop yield - Irrigation frequency - N-leaching - RZWQM - Summer maize
Classification code:444 Water Resources - 444.2 Groundwater - 453.2 Water Pollution Control - 483.1 Soils and Soil Mechanics - 601.1 Mechanical Devices - 722.1 Data Storage, Equipment and Techniques - 731 Automatic Control Principles and Applications - 731.1 Control Systems - 802.3 Chemical Operations - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2015.06.017
Database:Compendex
<RECORD 35>
Accession number:20152801011267
Title:Realizing national phase IV emission standard of heavy-duty diesel engine by using premixed methanol/diesel dual fuel
Authors:Wei, Lijiang (1); Ma, Yan (2); Han, Guopeng (1); Jiang, Shujun (2); Li, Yunqiang (2); Yao, Chunde (1)
Author affiliation:(1) State Key Laboratory of Engines, Tianjin University, Tianjin, China; (2) Weichai Power Co., Ltd., Weifang, China
Corresponding author:Yao, Chunde
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:269-274
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Premixed methanol diesel dual fuel (PMDDF) is a combustion mode in which methanol is injected from the intake port and then ignited by the direct injected diesel in the cylinder. Many studies have shown that PMDDF mode has the potential to reduce NO<inf>x</inf> and PM emissions simultaneously. In this study, investigation on realizing national phase IV emission standard by using PMDDF combustion mode coupling with diesel oxidation catalyst (DOC) and particulate oxidation catalyst (POC) was carried out on a 6-cylinder heavy-duty diesel engine. The effects of premixed methanol on engine combustion process and fuel economy were also investigated. The experimental results showed that with the engine power keeping unchanged, the emission level of the engine was improved from national phase III to IV by using PMDDF combustion mode and the simple aftertreatment DOC+POC. And the specific fuel consumption almost remained unchanged. This technology provided a new route for the realization of national phase IV emission standard. In addition, it was also found that the ignition delay of PMDDF combustion mode was prolonged and the combustion duration was shortened with the increase of premixed methanol ratio. At high engine load, the brake specific fuel consumption of PMDDF combustion mode was lower than that of baseline engine, but it was slightly higher at low engine load. Therefore, the premixed methanol ratio can be a little higher at high engine load but can not be very high at low engine load. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:20
Main heading:Dual fuel engines
Controlled terms:Catalysts - Combustion - Diesel engines - Direct injection - Engines - Fuel consumption - Fuel economy - Fuels - Ignition - Methanol - Particulate emissions
Uncontrolled terms:Brake specific fuel consumption - Diesel oxidation catalyst - Dual-fuels - Emission characteristics - Engine combustion process - Heavy-duty diesel engine - Particulate oxidation catalysts - Specific fuel consumption
Classification code:451.1 Air Pollution Sources - 521 Fuel Combustion and Flame Research - 521.1 Fuel Combustion - 522 Gas Fuels - 523 Liquid Fuels - 524 Solid Fuels - 612 Engines - 612.2 Diesel Engines - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 804.1 Organic Compounds
DOI:10.6041/j.issn.1000-1298.2015.06.039
Database:Compendex
<RECORD 36>
Accession number:20152801011261
Title:Mathematical model for predicting core temperature of commercial mutton chops during grilling
Authors:Pan, Teng (1); Meng, Jing (1); Cui, Jianyun (1); Guo, Huiyuan (1); Luo, Hailing (2); Ge, Keshan (1)
Author affiliation:(1) College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; (2) College of Animal Science and Technology, China Agricultural University, Beijing, China
Corresponding author:Ge, Keshan
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:234-238
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Grilled mutton chops are traditional meat products, and the quality is greatly influenced by the final core temperature. However, the core temperature of mutton chops during grilling is difficult to monitor. To predict the core temperature of mutton chops during grilling accurately and conveniently, a mathematical model based on grilling time and shapes of mutton chops was established. Mutton chops with different cross-sectional areas of lean meat from 7 cm<sup>2</sup> to 15 cm<sup>2</sup> were grilled in an electric heat oven at 120 or 220. Fifteen samples were grilled independently at each temperature until the core temperature reached 75 and the temperature-time curves were recorded. Seven thermal probes were inserted into the different points of the mutton chops during grilling and the lowest temperature was taken as the core temperature. The model for predicting core temperature with grilling time and cross-sectional areas of lean meat was built with regression method, which was used to evaluate the quality of grilled mutton chops. The results showed that the established model could well predict the temperature changes of grilled mutton chops and the relative errors between simulated and measured results were lower than 6%. Different quality characteristics of mutton chops were formed under different grilling temperature based on the application of the model. The mathematical model could provide a convenient and timely method for predicting the core temperature of mutton chops during grilling. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:21
Main heading:Meats
Controlled terms:Forecasting - Image quality - Mathematical models - Regression analysis - Thermal processing (foods)
Uncontrolled terms:Core temperature - Cross sectional area - Grilled mutton chops - Grilling time - Quality characteristic - Regression method - Temperature changes - Temperature-time curves
Classification code:741 Light, Optics and Optical Devices - 822.2 Food Processing Operations - 822.3 Food Products - 921 Mathematics - 922.2 Mathematical Statistics
DOI:10.6041/j.issn.1000-1298.2015.06.033
Database:Compendex
<RECORD 37>
Accession number:20152801011250
Title:Spatial variability of soil shrinkage characteristics in profile of slope disintegration body
Authors:Wei, Yujie (1); Wu, Xinliang (1); Cai, Chongfa (1)
Author affiliation:(1) College of Resource and Environment, Huazhong Agricultural University, Wuhan, China
Corresponding author:Cai, Chongfa
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:153-159
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Soil shrinkage curves of different depths in slope disintegration profiles were measured using soil shrinkage tester (SS-1 type) to investigate the spatial variability of soil shrinkage characteristics. Results showed that in the process of dehydration, soil linear shrinkage ratio displayed increase firstly and then attained to steady level. The relationship between linear shrinkage ratio and water content can be fitted well by the Logistic model. Soil shrinkage curves of red soil layer and speckle soil layer could be apparently divided into three stages. The variation rate in soil linear shrinkage ratio showed an unimodal trend with the decreasing of soil water content, which was not suited to that of sandy soil layer. Linear shrinkage ratio increased when soil texture changed to heavy. Significant difference was found in shrinkage characteristic between different layers of slope disintegration body. Radial shrinkage strain was larger than axial shrinkage strain for red soil layer and speckle soil layer but it was opposite for sandy soil layer, which indicated that horizontal cracks mainly occurred in surface layer during the soil dryness dynamic process. Correlation analysis showed that radial shrinkage strain was negatively correlated with sand content (r=-0.933); volume shrinkage strain and shrinkage limit were significantly correlated with clay content positively (r=0.891) and sand content negatively (r=-0.838), which indicated that soil shrinkage process was influenced by both soil texture and soil water state. Measures could be taken to reduce drastic variation of soil water content to prevent damage from shrinkage behavior in slope stability. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:25
Main heading:Soils
Controlled terms:Sand - Shrinkage - Slope stability - Soil moisture - Speckle - Textures
Uncontrolled terms:Correlation analysis - Granite soil - Linear shrinkage ratio - Shrinkage behavior - Shrinkage characteristic - Soil shrinkage curves - Soil water content - Spatial variability
Classification code:483.1 Soils and Soil Mechanics - 741.1 Light/Optics - 933 Solid State Physics - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2015.06.022
Database:Compendex
<RECORD 38>
Accession number:20152801011271
Title:Modeling and economy performance simulation of hybrid electric bulldozer under whole operation cycles
Authors:Zhang, Baodi (1); Zhang, Xin (1); Xi, Lihe (1); Jin, Biao (1)
Author affiliation:(1) School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing, China
Corresponding author:Zhang, Xin
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:294-302
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to simulate and analyze the economy performance of the tracked hybrid electric bulldozer under whole operation cycles, a secondary development of ADVISOR was applied and straight and steering dynamics model, track model, oil pump model and transfer case model, etc., were established in Matlab/Simulink, then the models of hybrid electric bulldozer and its compared bulldozer were built. The real two compared bulldozers' tests were conducted under straight cycles and steering cycles, respectively. And then the key operating parameters of powertrain source and powertrain terminal in simulations and tests, such as speed of engine, power of genset, voltage of super capacitors and traction and velocity of bulldozer, were compared to validate the accuracy of the models. The results showed that the established models had relatively high simulation accuracy. The economy performance was simulated under whole operation cycles by using the established models, which showed that the hybrid electric bulldozer had significant energy savings under both straight dozing and steering cycles, furthermore, the adoption of the engine-generator set optimal efficiency curve control strategy can further enhance the energy saving effect. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:16
Main heading:Electric machine theory
Controlled terms:Earthmoving machinery - Electric generators - Electric machine control - Energy conservation - Engines - MATLAB - Models - Powertrains - Transfer cases (vehicles)
Uncontrolled terms:Economy performance - Energy-saving effect - Engine generator set - Hybrid electric bulldozer - Operating parameters - Operation cycles - Secondary development - Simulation
Classification code:405.1 Construction Equipment - 525.2 Energy Conservation - 612 Engines - 663.2 Heavy Duty Motor Vehicle Components - 691.1 Materials Handling Equipment - 705.1 Electric Machinery, General - 705.2 Electric Generators - 902.1 Engineering Graphics - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2015.06.043
Database:Compendex
<RECORD 39>
Accession number:20152801011270
Title:Optimized design of internal engine piston skirt with bionic structure
Authors:Wu, Bo (1); Cong, Qian (1); Xi, Peng (1)
Author affiliation:(1) Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun, China; (2) Engineering Training Center, Changchun Institute of Technology, Changchun, China
Corresponding author:Cong, Qian
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:287-293 and 318
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Research of existing automobiles of energy-saving and emission reduction is very important in the interim period before popularization of new energy automobiles. Some research results showed that about 50% frictional loss of engine was generated from friction pair of piston-cylinder liner system. Based on great usage amount of engines, frictional loss of engine was reduced within a narrow range; it could exert a large influence on energy consumption and environmental enhancement. The 1.6 L engine of Jetta car was used as testing subject. The pits on the Cybister bengalensis' surface, which could reduce drag and increase wearability, were applied to the main friction pair of engine-piston skirt for the first time. Firstly, the ranges of bionic apertures and separation distances were designated according to the configuration sizes of pits of cybister surface. Then the optimal bionic apertures and separation distances were determined by relative speed drag reduction rate on the basis of relative speed of bionic piston under the three calibration conditions. The ultimate speed of bionic piston was increased as drag reduction rate increased, and the anti-drag and wear-resisting were improved with smaller friction of bionic piston. Secondly, the stress arrangement of thermal-structure coupling analysis of standard piston skirt showed that the maximum stress was at the top and the maximum deformation was at the bottom. Variable aperture and variable line spacing of bionic holes was innovatively designed. Larger aperture and greater line spacing were located near the piston top. Three levels and three factors orthogonal test was made. Level one was holes distribution, which included uniform form, stagger form, line by line to increase; level two was bionic hole, including through-hole, pit, pit and through-hole alternating; level three was bionic aperture, including three bionic aperture sizes. Under the worst conditions, standard and nine bionic pistons were done by finite element thermal-structure coupling analysis. Three typical target variables were selected as test indexes, which were maximum stress of the top of piston, maximum deformation of piston skirt and maximum stress of spill port. The test indexes of nine kinds of bionic pistons were optimized by range analysis. Primary and secondary factors were bionic hole, holes distribution and bionic aperture, and optimal combination were stagger form, pit and through-hole alternating, and bionic aperture as 2.5, 2, 1.5, 1 mm. Finally, three pistons as standard piston, the best optimal performance bionic piston and optimal combination piston were selected, and the durability tests were done on test bench of engine. The temperature of the top of piston in every air cylinder, gas pressure gradient, piston wear extent and piston skirt's surface roughness were got, which could verify the superiorities of anti-drag and wear-resisting of bionic pistons. Results of simulation and bench test indicated that the former was better in deformation and its skirt bottom had less wear and better lubrication when comparing the variable aperture, variable line spacing and uniform distribution bionic holes; through-hole unloaded concentrated stress best; the best aperture range was 1~3.5 mm; stagger form could avoid blind angle in oil gathering, configuration oil and storage chip; bionic piston abrasion loss was reduced by 90%, power of work gas was increased by 50% in the air cylinder and heat dissipation efficiency was increased by 0.5% compared with standard piston. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:18
Main heading:Engine pistons
Controlled terms:Air lubrication - Automobile engines - Bionics - Cylinder configurations - Deformation - Drag - Drag reduction - Durability - Emission control - Energy conservation - Energy utilization - Engine cylinders - Engines - Finite element method - Friction - Internal combustion engines - Pistons - Surface roughness - Testing - Tribology - Wear resistance
Uncontrolled terms:Bionic design - Cybister bengalensis - Energy saving and emission reductions - Environmental enhancements - Gas pressure gradient - Separation distances - Test optimization - Uniform distribution
Classification code:421 Strength of Building Materials; Mechanical Properties - 423.2 Non Mechanical Properties of Building Materials: Test Methods - 451.2 Air Pollution Control - 525.2 Energy Conservation - 525.3 Energy Utilization - 607.2 Lubrication - 612 Engines - 661.1 Automotive Engines - 731.1 Control Systems - 921.6 Numerical Methods - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.6041/j.issn.1000-1298.2015.06.042
Database:Compendex
<RECORD 40>
Accession number:20152801010858
Title:Analysis of factors influencing power density for axial-piston pump
Authors:Chen, Shumei (1); Yan, Binqu (1); Chen, Chuanming (1)
Author affiliation:(1) School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:355-362
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to further increase the power density for axial-piston pump, the quantitative formulas were derived and the most important factors were studied. One factor was the amount of volumetric displacement of pump per revolution divided by the spatial volume of pump, and the analysis indicated that it was determined by swash-plate angle and piston pitch-radius, and 60% increase of it could be obtained by using an inverted piston-slipper design. The other factor was the maximal speed which was determined by the self-priming ability (SPA) of pump. The analysis result showed that the SPA was affected by resistance caused by viscous resistance and forced vortex, and the ability dropped with the rotating speed increasing, which was the defect of current structure of cylinder block. In order to overcome the defect, a new structure of cylinder block with bidirectional inclined cylinder block hole was presented, and the results of simulation demonstrated that SPA of axial-piston pump was increased by 45.4%. Finally, to meet the requirement of large displacement pump, a symmetrical X shape axial-piston pump was proposed and its power density was verified theoretically. The analysis result showed that the power density was increased by 43% compared with a double-pump. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:12
Main heading:Pumps
Controlled terms:Cylinder blocks - Cylinders (shapes) - Defects - Factor analysis - Pistons - Reciprocating pumps
Uncontrolled terms:Axial piston pump - Inclined cylinders - Large displacements - Power densities - Quantitative formula - Self-priming - Slipper pairs - Viscous resistance
Classification code:408.2 Structural Members and Shapes - 423 Non Mechanical Properties and Tests of Building Materials - 612.1.1 Internal Combustion Engine Components - 618.2 Pumps - 922.2 Mathematical Statistics - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2015.06.051
Database:Compendex
<RECORD 41>
Accession number:20152801011248
Title:Influence of straw mulching on soil moisture characteristics during seasonal freeze-thaw period
Authors:Fu, Qiang (1); Li, Tienan (1); Li, Tianxiao (1); Cui, Song (1)
Author affiliation:(1) School of Water Conservancy & Civil Engineering, Northeast Agricultural University, Harbin, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:141-146
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to analyze the effect of straw mulching on changing characteristics of soil moisture during seasonal freeze-thaw period, Harbin City was selected as the objective study area, and soil liquid volumetric moisture content at different soil depths (i.e. 20, 40, 60, 100, 140, 180 cm) was measured in the field under straw mulching thicknesses of 5, 10 and 15 cm in winter, and bare soil was taken as control. Meanwhile, the meteorological data was obtained from automatic meteorological station in the study area. The results showed that straw mulching thickness can retard the temporal inflection point of increasing or decreasing of soil volumetric moisture content between 0 cm and 60 cm soil depth, the retard effectiveness was more obvious with thicker straw mulching, and the retard effectiveness was more obvious in freezing period than that in thawing period. The snowmelt infiltration was prevented by the straw mulching at the beginning of thawing period, thus the liquid volumetric moisture content appeared temporary peak value at soil depth of 20, 40 and 60 cm under the condition of bare soil. However, the liquid volumetric moisture content was lower in bare soil treatment than that in other three treatments due to straw mulching at the end of thawing period. The straw mulching could effectively adjust and remain the liquid volumetric moisture content at soil depth of 0~60 cm during freeze-thaw period, meanwhile, the adjustment effectiveness was weakened with the increase of soil depth. Both snowmelt and straw mulching can effectively increase soil moisture, but the increasing capability of soil moisture decreased with increasing soil depth. The order of the increasing capability of soil moisture at soil depth of 0~60 cm was 15, 10 and 5 cm thickness of mulching straw. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:17
Main heading:Soils
Controlled terms:Freezing - Liquids - Meteorology - Moisture - Moisture determination - Snow melting systems - Soil moisture - Thawing
Uncontrolled terms:Alpine regions - Different soils - Freeze-thaw - Inflection points - Meteorological data - Meteorological station - Straw mulching - Volumetric moisture content
Classification code:443 Meteorology - 483.1 Soils and Soil Mechanics - 822.2 Food Processing Operations - 931.2 Physical Properties of Gases, Liquids and Solids - 944.2 Moisture Measurements
DOI:10.6041/j.issn.1000-1298.2015.06.020
Database:Compendex
<RECORD 42>
Accession number:20152801011231
Title:Self-adaptive sliding mode control based on input fuzzy for agricultural tracked robot
Authors:Jiao, Jun (1); Kong, Wen (1); Wang, Qiang (1); Chen, Liqing (2); Gu, Lichuan (1); Gao, Ya (1)
Author affiliation:(1) School of Information and Computer, Anhui Agricultural University, Hefei, China; (2) School of Engineering, Anhui Agricultural University, Hefei, China
Corresponding author:Gu, Lichuan
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:14-19 and 13
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Aiming at the characteristics of parameter perturbations and the effect of disturbance outside in agricultural tracked robot control system, a self-adaptive fuzzy sliding mode control was proposed based on fuzzy logic theory to improve the control precision and stability, which combined sliding mode control with fuzzy theory. Firstly, the motion equation of agricultural tracked robot was derived and analyzed. Secondly, an integral sliding mode surface was proposed, and an adaptive fuzzy sliding mode control was designed based on equivalent efficiency control and switching control, which held the celerity and robustness of sliding mode control and also weakened the buffeting very well. The simulation and test results showed that compared with conventional sliding mode control method, the proposed control possessed the advantages of good adaptability and robustness to outside disturbances and parameter uncertainty, and also had fast dynamic response and well tracking performance, which was feasible for agricultural tracked robot controlling system. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:17
Main heading:Adaptive control systems
Controlled terms:Agriculture - Dynamic response - Equations of motion - Fuzzy logic - Fuzzy systems - Robots - Robustness (control systems) - Sliding mode control
Uncontrolled terms:Adaptive fuzzy sliding mode controls (AFSMC) - Adaptive sliding mode control - Conventional sliding mode controls - Fuzzy sliding mode control - Integral sliding mode - Parameter perturbation - Sliding modes - Tracked robot
Classification code:408.1 Structural Design, General - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 731 Automatic Control Principles and Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.2 Calculus
DOI:10.6041/j.issn.1000-1298.2015.06.003
Database:Compendex
<RECORD 43>
Accession number:20152801011242
Title:Pressure fluctuations around volute tongue of centrifugal pump
Authors:Cai, Jiancheng (1); Pan, Jie (2); Andrew, Guzzomi (2)
Author affiliation:(1) College of Engineering, Zhejiang Normal University, Jinhua, China; (2) School of Mechanical and Chemical Engineering, The University of Western Australia, Perth, Australia
Corresponding author:Pan, Jie
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:92-96 and 72
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Pressure fluctuations inside centrifugal pump, especially those near the volute tongue, are the primary excitations to pump vibration and noise. The performance and pressure fluctuations of a centrifugal pump running at different flow rates and variable speeds were experimentally studied. The pump performance measurement showed that the pump worked at low flow rate condition, and the pump hydraulic performance varied with the rotational speed according to one-dimensional design theory. The pressure fluctuation measurement showed that discrete components were the main contributions in the pressure fluctuation spectra, especially the blade passing frequency (BPF) and its second harmonic. The overall strength of pressure fluctuation was approximately 1% of the reference dynamic pressure, and it varied in a quadratic function form with rotary speed. At a constant rotation speed, the pressure fluctuation magnitude at the outlet side of volute tongue had no obvious change with the decrease of flow rate, but places at the inner side and tongue tip experienced noticeable increase at sufficiently low flow rates owing to the pressure fluctuations below BPF. The study provided a basis for future study of flow-induced pump vibration and noise. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:17
Main heading:Flow rate
Controlled terms:Centrifugal pumps - Pumps - Speed
Uncontrolled terms:Blade passing frequency - Discrete components - Off design condition - Pressure fluctuation - Pressure fluctuation measurements - Primary excitations - Rotational speed - Spectrum
Classification code:618.2 Pumps - 631 Fluid Flow - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2015.06.014
Database:Compendex
<RECORD 44>
Accession number:20152801011244
Title:Review on irrigation technology applying sewage effluent-advances and prospects
Authors:Li, Yanfeng (1); Li, Jiusheng (1); Zhao, Weixia (1); Wang, Zhen (1)
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
Corresponding author:Li, Jiusheng
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:102-110
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The use of sewage effluent subjected to proper treatment for agricultural irrigation has been increasingly considered as a supplemental source of freshwater in many countries where a shortage of potable water is current reality. However, concern exists over the pollution risk due to the toxic accumulation from sewage effluent, which is the main restraint on the application of sewage effluent irrigation. Extensive researches on system stability, environmental sustainability, and efficient control are highly necessary to ensure the efficient and safe use of sewage effluent for agricultural irrigation. The effects of sewage effluent application on drip emitters, irrigation system, environments and agricultural products were reviewed. The behaviors and interaction between nutrients, salts, microorganisms and typical pollutants were summarized. Several theoretical and technical issues that need to be further studied, including the micro mechanism and macro behaviors of the influences of sewage application on irrigation system performance, the dynamics process of environmental changes imposed by sewage irrigation, the effects of sewage application on nutrient uptake and utilization, and efficiently safe control mechanisms of sewage irrigation, were prospected. Expected researches on these issues can add new knowledge to the regulation theory of water, nutrients and salts for irrigation and it will be a contribution to enhancing the efficiency and safety of use of sewage effluent for agricultural irrigation. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:68
Main heading:Irrigation
Controlled terms:Agricultural products - Agriculture - Effluent treatment - Effluents - Environmental regulations - Fertilizers - Nutrients - Pollution - Potable water - Safety engineering - Salts - Sewage - Sustainable development - System stability
Uncontrolled terms:Environmental safety - Irrigation systems - Nutrient uptake - Safety regulations - Sewage irrigation
Classification code:444 Water Resources - 452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 454.2 Environmental Impact and Protection - 454.3 Ecology and Ecosystems - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 911.2 Industrial Economics - 914 Safety Engineering - 961 Systems Science
DOI:10.6041/j.issn.1000-1298.2015.06.016
Database:Compendex
<RECORD 45>
Accession number:20152801011247
Title:Soil moisture characteristics and its influence on jujube tree transpiration in loess hilly region
Authors:Wei, Xinguang (1); Nie, Zhenyi (2); Liu, Shouyang (4); She, Tan (1); Ma, Jianpeng (2); Wang, Youke (1)
Author affiliation:(1) College of Water Resources and Architecture Engineering, Northwest A&F University, Yangling; Shaanxi, China; (2) National Engineering Research Center for Water Saving Irrigation at Yangling, Yangling; Shaanxi, China; (3) Institute of Soil and Water Conservation, Northwest A&F University, Yangling; Shaanxi, China; (4) Laboratory of Modeling Agricultural and Hydrological Systems in the Mediterranean Environment, French National Institute of Agronomic Research, Avignon, France; (5) Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling; Shaanxi, China
Corresponding author:Wang, Youke
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:130-140
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to explore the relationships between jujube tree transpiration and soil moisture in semi-arid loess hilly area, soil moisture and jujube tree sap flow were monitored for three consecutive years. Results showed that temporal and spatial variability of soil moisture were significant. Soil moisture increased with the increase of soil depth but its coefficient of variation decreased gradually in the vertical direction. According to the variation of soil moisture, soil depth was divided into three layers from top to bottom: soil moisture changing layer (0~2.6 m), dried soil layer (2.6~6.0 m) and soil moisture recovery layer (6.0~10.0 m). Parameters of jujube tree sap flow were significantly different between growth period and dormant period, therefore, the growth period of jujube tree could be demarcated more accurately. The growth period divided based on sap flow characteristics lasted about 160 d, which was similar to that determined by sprout and defoliation observation method, but it started and ended nearly 5 d in advance. The increase of soil moisture led to forward of minimum values and delay of maximum values of jujube tree sap flow, the "lunch break" time was shortened, but the transpiration time was strongly prolonged, and vice versa. Jujube tree sap flow increased at the early growth stage, and the positive correlation between transpiration and soil moisture were significant at the middle and late growth stages. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:29
Main heading:Soil moisture
Controlled terms:Forestry - Moisture - Sediments - Soil surveys - Soils - Transpiration
Uncontrolled terms:Coefficient of variation - Dried soil layers - Loess hilly regions - Observation method - Positive correlations - Sap flow - Temporal and spatial variability - Vertical direction
Classification code:483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 643 Space Heating, Ventilation and Air Conditioning - 801.4 Physical Chemistry - 821.0 Woodlands and Forestry
DOI:10.6041/j.issn.1000-1298.2015.06.019
Database:Compendex
<RECORD 46>
Accession number:20152801011259
Title:Impact of frozen storage on protein, lipid oxidation and water holding capacity of yak meat
Authors:Li, Ruren (1); Han, Ling (1); Yu, Qunli (1); Rong, Liangyan (2); Li, Hongbo (3)
Author affiliation:(1) College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China; (2) Station of Grassland Technology Extension, Lanzhou, China; (3) Longxi Zhongtian Halal Food Company Limited, Longxi, China
Corresponding author:Han, Ling
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:218-225
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The aim of this paper was to investigate the changes of protein, lipid oxidation and its impact on water holding capacity of Psoas major, Quadriceps femoris and Longissimus dorsi from yak during 140 d of frozen storage (-18). Samples were analyzed at sampling times upon thawing (0, 28, 56, 84 and 140 d) for lipid (TBARS, hexanal) and protein oxidation products (α-aminoadipic and γ-glutamic semialdehydes, α-aminoadipic acid, Schiff bases). During the frozen storage, heme-iron and superoxide dismutase played an important role in the lipid oxidation process of Longissimus dorsi. Owing to a lower content of heme-iron and a relatively higher content of superoxide dismutase, Longissimus dorsi had a lower content of TBARS and hexanal. Frozen storage significantly influenced the oxidative stability of proteins in Psoas major and Quadriceps femoris. The protein oxidation process of PM and QF was co-regulated by heme-iron, superoxide dismutase and catalase. Because of the promoting oxidation of heme-iron, the content of α-aminoadipic and γ-glutamic semialdehydes were also significantly improved. However, the content of heme-iron in Psoas major was significantly higher than Quadriceps femoris, the content of α-aminoadipic and γ-glutamic semialdehydes in Psoas major and Quadriceps femoris had no significant differences due to the higher content of superoxide dismutase and catalase. The content of α-aminoadipic acid was relatively higher because of the higher content of heme-iron in Psoas major, but the content of α-aminoadipic acid in Psoas major was significantly lower than Quadriceps femoris (P<0.05). Furthermore, the water holding capacity of yak meat was significantly affected by protein carbonylation reaction during the frozen storage. Owing to the lowest antioxidant enzyme activity and the highest heme-iron, the water holding capacity of Quadriceps femoris was the worst in three kinds of yak meat. The purge of Quadriceps femoris was higher than Longissimus dorsi for 3.55 times. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:29
Main heading:Porphyrins
Controlled terms:Antioxidants - Carbonylation - Enzyme activity - Enzymes - Functional groups - Iron - Meats - Oxidation - Oxidation resistance - Oxygen - Proteins
Uncontrolled terms:Antioxidant enzyme - Antioxidant enzyme activity - Frozen storage - Heme iron - Oxidative stability - Protein carbonylation - Super oxide dismutase - Water holding capacity
Classification code:461.9 Biology - 545.1 Iron - 802.2 Chemical Reactions - 804 Chemical Products Generally - 804.1 Organic Compounds - 822.3 Food Products
DOI:10.6041/j.issn.1000-1298.2015.06.031
Database:Compendex
<RECORD 47>
Accession number:20152801011243
Title:Experiment and calculation method of fluid leakage in flow passage of pump chamber on centrifugal pump
Authors:Liu, Zailun (1); Sun, Yu (1); Wang, Dongwei (1); Hou, Yihua (1); Ma, Xijin (1)
Author affiliation:(1) College of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, China; (2) Engineering Institute of Wenzhou Pump and Valve, Lanzhou University of Technology, Wenzhou, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:97-101
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A special testing apparatus was designed for measure and calculation of fluid leakage in flow passage of pump chamber. Gap-diameter ratio was changed by changing axial position of the impeller, i.e., changing the axial clearance of the pump chamber, when gap of wear-ring was 0.2 mm and 0.3 mm, respectively, and length of wear-ring was 15 mm, the import and export liquid pressure and fluid leakage in flow passage of pump chamber (gap-diameter ratio was 0.127, 0.101, 0.076, 0.051, 0.025 and 0.006, respectively) were tested and analyzed. The curves of leakage coefficient and pressure coefficient were obtained under different gap-diameter ratios conditions. In addition, the curves of velocity coefficient and gap-diameter ratio with different pressure coefficients were provided by calculating the experimental data. Results showed that under different gap-diameter ratios, fluid leakage coefficient and pressure coefficient in flow passage of pump chamber varied regularly, their relation curves were almost oblique lines, but gap-diameter ratio and gap of wear-ring can significantly affect curves. When the structure of pump was constant, decrease of axial clearance of pump chamber can effectively reduce fluid leakage, thus the volume efficiency of pump can be increased, and the optimum value range of axial clearance of pump chamber was 1~5 mm. Computational formula of fluid leakage in flow passage of pump chamber and determination method of velocity coefficient were presented. This study is of great significance to the volume efficiency of pump, wheel resistance loss, liquid pressure distribution in pump chamber and the calculation of axial thrust. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:14
Main heading:Pumps
Controlled terms:Centrifugal pumps - Flow of fluids - Leakage (fluid)
Uncontrolled terms:Computational formula - Determination methods - Diameter ratio - Different pressures - Leakage coefficient - Pressure coefficients - Pump chambers - Velocity coefficients
Classification code:452.3 Industrial Wastes - 618.2 Pumps - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2015.06.015
Database:Compendex
<RECORD 48>
Accession number:20152801011230
Title:Transmission performance of two-wheel drive electric tractor
Authors:Xie, Bin (1); Zhang, Chao (1); Chen, Shuo (1); Mao, Enrong (1); Du, Yuefeng (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing, China
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:8-13
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Two-wheel drive electric tractor has several advantages, including simple structure and electrically differential and flexible manipulation in narrowly closed working environment, and it enables us to make full use of adhesion and improve adhesion utilization and dynamic performance. The overall structure program of two-wheel drive electric tractor was proposed which adopted two 5 kW drive motors. Electric drag traction performance was analyzed from both electric tractor load stress and traction efficiency aspects. Matching analysis of transmission components was also put forward based on force balance equation of electric tractor cultivation operation. Tests on traction performance, load startup and transportation conditions were done in the built electric tractor driving test platform. According to the result, the proposed electric tractor torque reached 1800 N·m, which can meet the need of deeper tillage operations. With load started, driving torque value was increased from 700 N·m to 1600 N·m and speed was increased from 0 to 7 km/h, which spent about 1.1 s. As for transport experiments, when transported goods were weighed 1710 kg, the speed reached 6.5 km/h. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:9
Main heading:Electric traction
Controlled terms:Adhesion - Automobile testing - Electric drives - Traction (friction) - Tractors (agricultural) - Tractors (truck) - Transmissions - Wheels
Uncontrolled terms:Dual-motors - Electric tractors - Flexible manipulations - Force balance equation - Traction efficiency - Transmission components - Transmission performance - Transport experiments
Classification code:601.2 Machine Components - 602.2 Mechanical Transmissions - 662 Automobiles and Smaller Vehicles - 663 Buses, Tractors and Trucks - 663.1 Heavy Duty Motor Vehicles - 682.1.1 Railroad Cars - 705 Electric Generators and Motors - 801 Chemistry - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2015.06.002
Database:Compendex
<RECORD 49>
Accession number:20152801011229
Title:Control and Interaction System for Tractor Hydro-mechanical CVT
Authors:Wang, Guangming (1); Zhu, Sihong (1); Shi, Lixin (1); Wang, Shenghong (1); Zhang, Haijun (1); Vanthinh, Nguyen (1)
Author affiliation:(1) College of Engineering, Nanjing Agricultural University, Nanjing, China; (2) College of Automotive Technology, Hung Yen University of Technology and Education, Hung Yen, Viet Nam
Corresponding author:Zhu, Sihong
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:1-7
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to satisfy the tractor speed and power requirements under various operation conditions, the control and interaction system of tractor hydro-mechanical CVT was studied. The principle of power split mechanism and infinite speed variation of a new kind of hydro-mechanical CVT were introduced. And the control method of infinite speed variation and load adaptive adjustment were analyzed. On the one hand, a point-to-point control method was studied through dividing the range of speed ratio into 96 work points, and building the mapping between work point and the actuators such as the exciting voltage of pump, the electromagnetic valve for pump flow direction control, and the electromagnetic valve for clutch control, the controller described the mapping as a control table to realize the infinite speed variation and power shift. On the other hand, based on the target of engine power control, an automatic speed ratio control strategy was proposed to follow the change of load and the corresponding fuzzy control table was acquired. The interaction system and control unit of tractor hydro-mechanical CVT were designed for further research. Finally, based on the presented control system, some key experiments such as tractor acceleration and load adaptive speed ratio adjustment were made. The test of acceleration showed that there was a stationary process for speed ratio adjustment with algorithm of point-to-point control under different work conditions due to the open loop control method. The test of load adaptive speed ratio adjustment showed that the speed ratio was quickly changed under different load levels to maintain the constant of engine power because of the closed loop control method. Results showed that the designed control system was reliable and the proposed algorithm was correct. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:18
Main heading:Adaptive control systems
Controlled terms:Acceleration - Control systems - Engines - Fuzzy control - Mapping - Speed - Tractors (agricultural) - Tractors (truck) - Variable speed transmissions
Uncontrolled terms:Closed-loop control - Continuously variable transmission - Electromagnetic valves - Fuzzy reasoning - Hydro-mechanical CVT - Operation conditions - Point to point control - Speed ratio control
Classification code:602.2 Mechanical Transmissions - 612 Engines - 663.1 Heavy Duty Motor Vehicles - 731 Automatic Control Principles and Applications - 731.1 Control Systems - 902.1 Engineering Graphics - 921 Mathematics - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2015.06.001
Database:Compendex
<RECORD 50>
Accession number:20152801011253
Title:Simulation of soil cohesion by state-space approach in ephemeral gully of hilly Loess Plateau
Authors:Li, Zhenwei (1); Zhang, Guanghui (1); Geng, Ren (3); Wang, Hao (3)
Author affiliation:(1) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling; Shaanxi, China; (2) University of Chinese Academy of Sciences, Beijing, China; (3) School of Geography, Beijing Normal University, Beijing, China
Corresponding author:Zhang, Guanghui
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:175-182
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Ephemeral gully is widespread on the hilly Loess Plateau of China. A better understanding of the spatial variability in soil cohesion across the ephemeral gully will improve understanding of ephemeral gully erosion. However, quantitative research about the spatial heterogeneity of soil cohesion is quite few. The study was conducted to investigate and predict the spatial variation of soil cohesion in an ephemeral gully of hilly Loess Plateau by using classical linear regression and state-space methodologies. The results showed that soil cohesion had a moderate variation, and it was considerably influenced by elevation, clay content, sand content and bulk density. The autocorrelation functions for above-mentioned five variables were sufficient to identify their spatial representatives. The cross-correlation functions showed a strong spatial dependence between soil cohesion and elevation, clay content, sand content and bulk density. All the derived state-space models described the spatial variation of soil cohesion better than that of the equivalent linear regression models. The best state-space models based on clay content can explain 97.2% of the soil cohesion variation. Thus, state-space model was recommended as a useful tool to predict soil cohesion in ephemeral gullies of the hilly Loess Plateau. Furthermore, the result can provide valuable data base for setting up soil erosion model. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:24
Main heading:Landforms
Controlled terms:Adhesion - Erosion - Linear regression - Regression analysis - Sediments - Soils - State space methods
Uncontrolled terms:Autocorrelation functions - Cross-correlation function - Ephemeral gullies - Ephemeral gully erosions - Loess Plateau - Loess plateau of chinas - Soil cohesion - State - space models
Classification code:481.1 Geology - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 801 Chemistry - 921 Mathematics - 922.2 Mathematical Statistics - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2015.06.025
Database:Compendex
<RECORD 51>
Accession number:20152801011232
Title:Design and experiment on reducing soil adhesion and anti-slip structure of profiling elastic press roller
Authors:Jia, Honglei (1); Wang, Wenjun (1); Zhuang, Jian (1); Luo, Xiaofeng (1); Yao, Pengfei (1); Li, Yang (1)
Author affiliation:(1) College of Biological and Agricultural Engineering, Jilin University, Changchun, China; (2) Key Laboratory of Bionics Engineering, Ministry of Education, Jilin University, Changchun, China
Corresponding author:Zhuang, Jian
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:20-27
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:During the working process of press roller, the deficiencies in the soil adhesion and the large slip rate on the profiling elastic press roller are existed. Based on the flexible geometry features of the typical soil animal body surface, the reducing soil adhesion and anti-slip structure were designed to solve the problem. The structure consists of rubber bulges, which are fixed by the existing bionic rib structure. This structure has the advantages of less soil adhesion, lower slip rate, more uniform pressure distribution and better soil crushing effect. The movement process of the reducing soil adhesion and anti-slip structure was researched by using theoretical calculation and kinematics analysis, the characteristic equation of rubber bulges and the value ranges of bulge height and rib height were obtained. The orthogonal combination experiments of three factors and three levels were designed and performed. The results showed that the primacy sequence of the experiment factors influencing soil adhesion was: rubber bulge height (H), rib height (L), total loads (F) and the primacy sequence of the experiment factors influencing slip rate was: rib height, rubber bulge height and total loads. Optimal levels of the experiment factors influencing soil adhesion and slip rate were F of 450.0 N, H of 13.9 mm, L of 15.1 mm. At the same time, verification tests and comparison tests were conducted in the field. The results showed the soil adhesion quality was 39.2 g, the slip rate was 3.89%, compared with the roller without the reducing soil adhesion and anti-slip structure, the soil adhesion quality was reduced by 60.1% and the slip rate was reduced by 54.3%. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:11
Main heading:Structural design
Controlled terms:Adhesion - Presses (machine tools) - Rollers (machine components) - Rubber - Soils
Uncontrolled terms:Characteristic equation - Geometry features - Kinematics analysis - Press rollers - Profiling - Slip structures - Theoretical calculations - Verification tests
Classification code:408.1 Structural Design, General - 483.1 Soils and Soil Mechanics - 601.2 Machine Components - 603.1 Machine Tools, General - 801 Chemistry - 818.1 Natural Rubber - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2015.06.004
Database:Compendex
<RECORD 52>
Accession number:20152801011258
Title:Effect of Lactoferrin-polyphenol conjugates on stability of β-carotene emulsions
Authors:Liu, Fuguo (1); Wang, Di (2); Yang, Wei (1); Yuan, Fang (1); Gao, Yanxiang (1)
Author affiliation:(1) College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; (2) College of Science, China Agricultural University, Beijing, China
Corresponding author:Gao, Yanxiang
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:212-217 and 225
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The objective of the study was to investigate the effect of lactoferrin-polyphenol conjugates on the stability of β-carotene emulsions. Conjugates of lactoferrin with polyphenol ((-)-epigallocatechin-3-gallate (EGCG), chlorogenic acid and gallic acid) were achieved by a free radical grafting procedure. The hydrophilic/hydrophobic characteristics of latoferrin and lactoferrin-polyphenol conjugates were studied by reverse-phase HPLC. Lactoferrin-polyphenol conjugates were used as emulsifiers to prepare β-carotene emulsions, and the stability of β-carotene emulsions was characterized by transmission profiles through using novel centrifugal sedimentation and β-carotene degradation in the emulsion during storage. The results implied that hydrophilicity of lactoferrin was increased after modified by polyphenol; compared with those stabilized by lactoferrin alone, the emulsions stabilized by lactoferrin-polyphenol conjugates were able to improve the stability of β-carotene emulsions and inhibit the deterioration of β-carotene in oil-in-water emulsions, and lactoferrin-chlorogenic acid conjugate was the best emulsifier among the lactoferrin-EGCG, lactoferrin-chlorogenic acid and lactoferrin-gallic acid conjugates. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:18
Main heading:Stability
Controlled terms:Convergence of numerical methods - Emulsification - Emulsions - Free radicals - High performance liquid chromatography - Hydrophilicity
Uncontrolled terms:Covalent conjugates - Epigallocatechin-3-gallate - Free radical grafting - Hydrophilic/hydrophobic - Lactoferrin - Oil-in-water emulsions - Polyphenols - Transmission profiles
Classification code:801 Chemistry - 802.3 Chemical Operations - 804 Chemical Products Generally - 921.6 Numerical Methods - 931 Classical Physics; Quantum Theory; Relativity - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science - 961 Systems Science
DOI:10.6041/j.issn.1000-1298.2015.06.030
Database:Compendex
<RECORD 53>
Accession number:20152801011254
Title:Characteristics and mineralization in soil of apple-derived biochar producecd at different temperatures
Authors:Zhao, Shixiang (1); Ji, Qiang (1); Li, Zhonghui (1); Wang, Xudong (1)
Author affiliation:(1) College of Natural Resources and Environment, Northwest A&F University, Yangling; Shaanxi, China; (2) Key Laboratory of Plant Nutrition and Agri-Environment in Northwest China, Ministry of Agriculture, Yangling; Shaanxi, China
Corresponding author:Wang, Xudong
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:46
Issue:6
Issue date:June 25, 2015
Publication year:2015
Pages:183-192 and 200
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The aim of this study was to investigate the influence of pyrolysis temperature on the physico-chemical properties of biochar, and the effect of biochar addition on carbon contents of soil organic matter fractions and carbon mineralization characteristics. Biochars were produced by fast pyrolysis of apple tree twigs at 300, 400, 500 and 600, respectively. Characterizations of biochars were determined by elemental analysis, Brunauer-Emmett-Teller (BET) for surface area, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy. Four kinds of biochar were added to soils at five application rates as soil only (control), soil+0.5% biochar, soil+1% biochar, soil+2% biochar and soil+3% biochar, which were incubated at 25 in lab. Carbon mineralization was analyzed by alkali absorption of CO<inf>2</inf> released periodically over 180 d. Soil samples were analyzed for microbial biomass carbon (MBC) and soil dissolved organic carbon (DOC). The results showed that the generated biochars contained 62.20%~80.01% of carbon (C), 2.72%~5.18% of hydrogen (H) and 15.99%~30.94% of oxygen (O). The BET surface area was 2.35~107.76 m<sup>2</sup>/g, basic functional groups were 0.11~0.40 mmol/g and acidic functional groups were 0.44~1.16 mmol/g. The increasing temperature (from 300 to 600) increased biochar C content, BET surface area and basic functional groups, while decreased the content of O and H, H/C and O/C ratio, acidic functional groups and total functional groups. Soil respiration, MBC and DOC were increased by biochar application. As pyrolysis temperature increased and biochar application rate decreased, soil respiration, MBC and DOC decreased in all soils. The mineralization of biochar C decreased significantly (P<0.05) from 7.86% to 0.60% when pyrolysis temperature increased from 300 to 600. A double-exponential equation was used to describe C mineralization kinetics and curve fitting was performed to mathematically define the size and turnover rate of two C source pools (labile and stable). The size of labile pool (A<inf>1</inf>) varied from 0.31 g/kg to 0.94 g/kg, while the size of stable pool (A<inf>2</inf>) varied from 6.88 g/kg to 30.82 g/kg. The decreased mineralization rates of the labile and stable pools (k<inf>1</inf> and k<inf>2</inf>) were resulted from the increased pyrolysis temperature and the decreased biochar application rates. Half-life of C in soil varied between 24.09 a and 44.76 a and increased with the increase of pyrolysis temperature and biochar application rates. Conclusively, pyrolysis temperature had important effect on the physico-chemical properties of biochar and therefore resulting in different stabilities of soil organic matter. Considering the carbon loss in the process of preparing biochar, 500 would be the optimal temperature for preparing apple-derived biochar due to the most significant promotion of soil organic carbon. ©, 2015, Chinese Society of Agricultural Machinery. All right reserved.
Number of references:43
Main heading:Soils
Controlled terms:Biogeochemistry - Biological materials - Chemical properties - Cracking (chemical) - Curve fitting - Fourier transform infrared spectroscopy - Fruits - Functional groups - Lakes - Mineralogy - Organic carbon - Organic compounds - Scanning electron microscopy
Uncontrolled terms:Bio chars - Half lives - Microbial biomass carbon - Pyrolysis temperature - Respiration rate
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 423 Non Mechanical Properties and Tests of Building Materials - 461.2 Biological Materials and Tissue Engineering - 482 Mineralogy - 483.1 Soils and Soil Mechanics - 741.1 Light/Optics - 801 Chemistry - 801.2 Biochemistry - 802.2 Chemical Reactions - 804.1 Organic Compounds - 821.4 Agricultural Products - 921.6 Numerical Methods
DOI:10.6041/j.issn.1000-1298.2015.06.026
Database:Compendex
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