Abstract:In light of the drawbacks of the 2-D wing, with the reference of traditional adjustments on the blower, a new hydraulic design method for the inlet guide vane was proposed. It was supposed that the fluid at the outlet of the inlet guide vane satisfied the conditions at the moment of uniform velocity. The spatial shape of the blade was controlled by the distributed rule of the blades, which were at staggered angles along the meridional streamline; this could be determined with a quarternary polynomial. A point-by-point integration method was adopted to draw the bone line of the blade. The blade was thickened on two sides on an unwrapped cylinder surface. Once complete, the spatial guide vane was used for a centrifugal pump, and the experiment was performed with the inlet guide vane fixed at various axial positions and pre-whirl angles. The results indicated that the designed guide vane enlarged the high efficiency scope and improved the hydraulic performance of the centrifugal pump. When compared with the performance of the centrifugal pump without inlet guide vane, the peak value of efficiency was enhanced by 2.0% after the 3-D guide vane was installed. This method improved efficiency and saved energy for the centrifugal pump.

Abstract:In order to analyze the effects of turbulence models on the numerical solution of double suction centrifugal pump through the use of Fluent software, a pump applied in domestic projects was chosen as a study object. 3-D steady numerical simulations were conducted by four different turbulence models, namely, the standard k-ε model, RNG k-ε model, realizable k-ε model and Reynolds stress equation. The results of steady numerical simulations were then used as initial values, and 3-D unsteady numerical simulations were conducted by the large eddy simulation（LES) method. Comparison of the numerical results with the experimental ones showed that in the situation of steady numerical simulations, four turbulence models could all be used in numerical simulation of double suction centrifugal pump, but the precisions of results were different. From this perspective, LES method will obtain much more accurate results.

Abstract:Cavitation performance curves of the model axial-flow pump were established on the basis of the hydraulic characteristic test with a numerical simulation of steady cavitating flow. Under the designed working conditions, the whole flow passage of the model axial-flow pump was carried out using a full cavitation model and a mixed two-phase flow model. The cavitation flow of the impeller was analyzed by comparing the primary cavitation, critical cavitation, and serious cavitation. The distribution of static pressure and vapor volume fraction of the blade’s suction surface were observed and the vapor volume fraction of the axial section was obtained. The simulation results showed that cavitation first occurred on the local low-pressure area on the back of the blade’s leading edge, which was close to the tip. When the pump ran at its critical cavitation point, the chord length of the cavitation region was 2/3 of the length from the back of blade’s leading edge to its trailing edge, approximately 50% of the back of the blade. After further increasing cavitation, the cavitation region extended towards the trailing edge and the fraction of its volume became larger. When local cavitation occurred in the impeller, it did not affect the power of the pump; however, when cavitation was serious, the over-current cross section close to the leading edge was obstructed, and the pump’s power declined seriously. The results of the simulation agreed with basis of the hydraulic characteristic test, revealed the axial flow impeller cavitation within the static characteristics. 

Abstract:The relationship between system efficiency and pump efficiency in low-head pumping stations depends on the hydraulic losses of its suction box and discharge passage. Based on the summary of the existing main methodologies for the relationship, the conventional basic hypothesis was verified and the antithesis discovered. The system efficiency was equal to the product of the passage efficiency and the pump efficiency; the passage losses occurred when there was no pump. Using CFD technology, the passage losses at different specific speeds modeled impellers with different types of suction boxes. Discharge passages were calculated and the relationship between the loss and flow rate in different systems was analyzed. When the passage loss was one with the pump, the product of the passage efficiency and the pump efficiency expressed the system efficiency. Near the optimal efficiency of the pump, the system efficiency expressed by the passage efficiency without the pump was nearly equal to the test results. The whole system, including the pump, must be considered for the optimal hydraulic design of the system.

Abstract:Using the shear stress transport turbulent model （SST), the 3-D unsteady numerical method was applied to simulate the flow of the centrifugal pump with the common-tongue and step-tongue. Various pressure fluctuations, radial hydraulic force on the impeller, and volute were obtained for the rotor-stator interaction. The analysis results indicated that the blade-passing frequency dominated the pressure fluctuation, the radial hydraulic force on the impeller and volute, which had periodic fluctuations. The amplitudes of the pressure fluctuation on the inlet and outlet detecting points of the pump were smaller with step-tongue than with common-tongue; the high-frequency components were also fewer. The radial hydraulic force on the volute of the pump with the step-tongue and its amplitude were also smaller than with the common-tongue. The distribution of radial hydraulic force on the impeller vector coordinates were almost circular using common-tongue and step-tongue.

Abstract:The life prediction of the pump and the counting method of stress were the subjects of this investigation. Aiming at the defect of the previous consideration that failed in attempts to count stress cycles, the concept of critical net stress was proposed to modify the counting principle. The improvements were made based on the concept of critical net stress. The improved counting method for predicting the fatigue life of an axial flow pump impeller was implemented. In addition, the key steps of the fatigue life prediction method were introduced based on 2-D probabilistic Miner-rule. 

Abstract:Numerical calculation was performed with 16 different conditions from 50%~120% of the design flow in shaft front-positioned and shaft rear-positioned tubular pump systems by using software Fluent 6.2. The Reynolds-averaged Navier-Stokes equations were discretized and solved with Spalart-Allmaras turbulence model and SIMPLEC algorithm. The results of numerical simulation were compared with model test data which was converted into the prototype size, and the result of the comparison showed that the tendency of performance change is in good agreement, the efficiency error between calculation data and model data is ±5% under the condition of the same flow. The basic flow pattern of inlet conduit, pump chamber and outlet conduit was analyzed and compared, and the reason for hydraulic loss was investigated. The results indicated that the flow pattern in the inlet and outlet conduit of the shaft front-positioned tubular pump system was good, and that the flow pattern in the inlet conduit of the shaft rear-positioned tubular pump was uniform and smooth. However, the flow pattern in the outlet conduit was in disorder. The hydraulic loss was relatively large, and the efficiency was lower; guide vane and shaft are the critical factors to affect the flow pattern of outlet conduit and arrangement efficiency, stall and vortexes are easily appeared under the influence of guide vane circulation and shaft.

Abstract:The surplus water head at industrial cooling towers is generally 4 to 15 meters. Using the surplus water head, a Francis turbine with super-low specific speed was designed to replace the fan motor in the cooling tower for energy saving. Based on the features of the surrounding environment, the runner blade airfoil was designed and optimized with 3-D numerical simulation through the whole flow passage of the turbine. Metal elliptical volutes and single-row ring guide vanes were applied in the structural design. After analyzing the numerical simulation results, an optimal model of 86% efficiency was selected for the physical model. The model test showed that the super-low specific speed Francis turbine met the dimensional requirement and had a high efficiency of 85.3%. Its stable performance can be popularized and applied in the capable local facilities.

Abstract:Computational fluid dynamics software Fluent 6.3 was adopted to simulate the flow of triangle circulation drip irrigation emitters, the models were built by 3-D software Pro/E. By analyzing the flow hydraulic performance and the turbulence characteristics of emitters, the mechanism of internal turbulent flow was revealed, the flow structure was optimized. Based on the simulation results, by changing the shape and position of the external and the small internal triangular, a new type of triangle circulation drip irrigation emitter with flow index of less than 0.5 was got, velocity distribution was uniform, within the allowable flow range and excellent anti-clogging performance. A theoretical basis for the triangle circulation emitters structure design and quantitative analysis was provided. 

Abstract:In order to study the effect of work pressure and soil physical properties on the flow rate of the subsurface drip irrigation (SDI) emitter, the soil fractal feature under different gradations was analyzed using fractal theory. Uniform design method was applied and the following four factors were considered in the experiment: the fractal dimension of the soil particle-weight, work pressure of the emitter, soil bulk density, and initial soil water content. The results showed that the fractal dimension was significantly influenced by the soil clay content; the fractal dimension increased as the soil clay content increased. When the PLASSIM SDI emitter discharge was increased, the soil fractal dimension decreased; the finer the soil texture was, the smaller the emitter discharge became. By taking soil fractal dimension factor into account, the experimental empirical formula for estimating the SDI emitter discharge has preferable universality.

Abstract:The effect of the infiltration process with initial moisture contents of 2.25%, 8.18%, 13.12% and 16.40% was examined by indoor uniformity earth pillar experiments. The infiltration water mineralization degree was 3g/L. Both cumulative infiltration and wetting front vs. time with different initial moisture contents infiltrated by saline water were analyzed. Fitting the relationship between cumulative infiltration and time with Kostiakov model, the results showed that the initial moisture content and soil infiltration capacity were negatively correlated. The relationship between wetting front advancing depth and time was fitted by power function. It proved that power function was obvious between them, the lower the initial moisture content was, the slower wetting front advancing rate would be. A 1D algebraic model was used to analyze soil moisture profiles; it was found that theoretical values were more accurate as the initial moisture contents increased. In brief, there was an intimate connection between soil infiltration capacity and initial moisture contents infiltrated by saline water. As the infiltration process was carried out, the influence of initial moisture contents on infiltration capacity gradually decreased.

Abstract:A technical method of increasing water resources and reducing water consumption was presented. The work of water-saving irrigation should be regarded as a system of engineering integrated with several technologies including planning and designing, product manufacturing, agronomic knowledge, service management and so on. New technologies relevant to water supply, water delivery and water distribution were introduced, and their development trend in the 21st century was described. The problems that need to be observed, analyzed and solved were also proposed from the systems engineering viewpoint of water-saving irrigation. 

Abstract:Performance during the seed-filling process directly impacted the seed quality of the metering device. The improved BP neural network prediction model was a metering device that filled at a single-grain rate η1 and the miss rates η2 was established using the Matlab neural network toolbox. The speed n, seed equivalent diameter d, seed-filling angle β and type hole diameter D were selected as the test factors, the test was carried out on 64 groups to determine the single-particle and miss rate. 55 groups were selected from the test as training samples. The Levenberg-Marquardt training method was used to train the establishment of a network. The remaining 9 groups were selected to simulate and predict the trained and improved BP neural network. n, d, β and D were set as the network’s input layers, η1 and η2 were set as the network’s output layers, the network structure was the 4-15-2 type three-layer network containing a single hidden layer. Predicted results showed that predicted values and experimental values were almost same, the predicted performance of seed-filling with the improved BP neural network method was feasible, the method can be used to optimize metering device design and provide a basis for the selection of working parameters, in addition to reducing test time and cost. 

Abstract:Traditional micro-cultivator field tests were restricted by many factors, and reliable tests in liner soil bins indoors could not be conducted; however, a new type of micro-cultivator testing platform was developed which could be performed continuously. The lengthy cyclic operations of the test platform were realized by adopting annular soil bins and closed-ended tracks. Functional trolleys were arranged individually so that they could walk steadily and swivel on six-wheeled walking mechanisms in the upper and lower trolleys, as well as the rotatable side wheel shaft. The platform merged upper and lower computer automatic controls, multi-sensors technology, wireless communication, gardens irrigation technology etc. Field conditions were simulated repeatedly. Performance and reliability experiments could both be carried out. More than ten parameters such as soil firmness, soil moisture, oscillation and forces of micro-cultivator handling etc. were collected, displayed and analyzed conveniently by the micro-cultivator testing platform. 

Abstract:A plastic film collector which could recycle plastic film for cotton fields during seedling period was designed, and the parameters of key components were analyzed and confirmed for film-loosening shovel, combined soil-dithering roller etc. The results of film separating from seedlings and soil were achieved very well by using claw type film-loosening shovel combined with flat spindle soil-dithering roller. The problem of breaking or blocking film was resolved by using a floating curl-up film roller which was synchronous with driving roller. Experimental results showed that the best working speed of the collector was 2~3km/h, and the recovery rate was higher than 95.7% and the injury rate to cotton seedlings was less than 2.37% when the height of cotton seedlings was lower than 30cm. The collector could pick up plastic film during seedling period for cotton fields which were used the planting pattern of one film two row seedlings.

Abstract:In order to counter the problem of reduced health promotion ability in typical grass with compacted roots, a root-cutting machine was designed for pasture. The machine used cam-driven of direct cutter to cut root vertically, greatly reducing resistance and perturbations of soil surface while cutting the root, which reached easy work in varies of forage. The machine destroyed solid soil, improved grassland, and increased grass yield. As proven by analyzing the velocity, acceleration and force of the machine was able to meet the needs of designing. It is a more ideal agricultural machine for forage grass. 

Abstract:30%。The results of the recent separating-lanting mechanism were first taken into consideration. This mechanism increased its rotational speed to improve its operational efficiency; yet by increasing the velocity of the needle of the separating-lanting bar, it increased the seeding injury rates at the same time. As a result, a newly designed mechanism, as well as studies on its affect on the survival and growth of rice, was introduced. The new type of separating-lanting mechanism had three separating planting bars with an elliptic plant gear system of high-erformance rice transplanters. Adding an additional separating planting bar kept the high operational efficiency of the rice transplanter while slowing the rotational speed to decrease seeding injury rate. Its kinematic model was established on the basis of transmission analyses of planetary elliptic gears systems; 3-D models were established by SolidWorks and the kinematics simulation was analyzed by ADAMS. Under the condition of the same operating efficiency, the speed decreased by 30%.

Abstract:The main technical factors and structure of the 3WDZ-6 type cotton top cutter was introduced. The characteristics of the mechanical system were presented, the research on automatic and closed-loop control system, which adjusted according to cotton height were also done. The cotton height experiment was tested using laser and ultrasonic sensors; the experimental results showed that the measuring error rate of the laser sensor was smaller than that of the ultrasonic sensor. The control and mechanical systems would meet the cotton top cutting agricultural requirements. 

Abstract:In order to lift sugarcane in harvesting, the whole stalk sugarcane harvester was designed. Virtual prototyping and key parts of the sugarcane harvester were simulated in PRO/E and ADAMS. The virtual experiment was conducted in order to study the lifting device, cutting device, gripping conveyor, laying transmission device and cleaning device, and to analyze the flow in various parts of the sugarcane harvester. A high-speed photography experiment was carried out to analyze lifter and gripping conveyor. The field experiment was validated. Virtual results showed that the virtual prototype could smoothly lift, cut, clamp, lay and clean. Reference value was provided for physical prototype in manufacture. 

Abstract:，生产率3 t/h。Aiming at some problems of shrub in western region, such as difficult to harvest, heavy labor intensity and low productivity and so on, moreover, in order to provide technical support for combating desertification, a self-propelled shrub harvester with special articulated carbody was developed. It can work in twist-waist manner and sway along the sector surface. Simultaneously, one new shrub harvesting method of vertical and horizontal profile modeling for shrub combined manual operation with adaptive profile modeling was proposed. Also experiments on caragana microphylla and sand willow harvest were carried out. The tested results were listed as follows: caragana microphylla missing cutting rate was equal or less than 0.8%, percent of broken stubble was 2.9%；sand willow missing cutting rate was equal or less than 0.8%, percent of broken stubble was 2.5%, the height of stubble was equal or less than 7 cm, reliability coefficient was 98.5%, the turnout was 3 t/h. 

Abstract:In view of the present situation regarding cotton-stalk harvest in the Yangtze valley and the Huanghe valley, a collecting and adaptive spring holding feed mechanism for interweave cotton-stalks was developed. This combine harvester integrated pick-up, cutting, collection loading and unloading. The results indicated that a feed quantity of 1.52kg/s, average cut length of cotton-stalk of 92.11%, and average throughput of 0.94hm2/h could be achieved by the experiment, which satisfied the automatic request of cotton-stalk combine harvester. 

Abstract:A round baler with revolute steel roller was designed. Based on the structure of the machine, the operating process and structural design of the key components of the machine were described simply. The baler was composed of driven system, drafting device, pickup, feeder, bale chamber, tying mechanism, hydraulic system and bale discharger, and so on. The movement parameters for the round baler were designed and computed. The motion trajectory of the feeder was described and the characteristics of the spiral-type bale chamber were analyzed simultaneously. In order to test the reliability and adaptability of the round baler, performance experiments and production evaluation were carried out under different operation conditions. 

Abstract:1%。The breadth of square baler pickup and roller rotating speed were designed. Simultaneously, contrast analysis on movement parameters of three sets of spring-tooth and four sets of spring tooth and the leakage ratio was carried out in the paper. The results indicated that leakage ratio of three sets of spring-tooth was less than 2% while pasture could avoid being piled up at ground and missed pick-up, and leakage ratio of four sets of spring-tooth was less than 1% .

Abstract:30%左右。In the course of the study, the radial feeding device of 9R-40 straw rubber was designed and installed. The experimental study on performance of straw rubber was carried out by going through alterring the rotational speed of spindle, the rotational speed of feeding roll and the shape of hammer in feeding mouth. By means of orthogonal experimental analysis, the best parameters of production rate were obtained. The rotational speed of spindle was 2980r/min, the rotational speed of feeding roll was267r/min and the shape of hammer was channel type. Based on the achievement, the production rate of 9R-40 straw rubber equipped with radial feeding device was improved by 30% comparied with original machine. 

Abstract:7MJ/Nm3。Energy balance analysis and calculations were made for two common kinds of biomass. It was proved that the heat of fixed carbon combustion was sufficient for volatile pyrolysis. The pressure distribution for cold cases in the dual fluidized bed was obtained by cold experiments. Finally, during the experiments of pellet gasification in dual fluidized bed, combustion conditions were able to be smoothly switched to gasification conditions with stable operation, and the calorific value of gas was able to reach 7MJ/Nm3.

Abstract:In the experiment, a fluidized bed was heated using Ar plasma and electricity. The temperature was tested at different levels of the reactor in the preheating, reacting period and finishing reacting with the content electricity heating rate. The results showed that the duration of time required to preheat the reactor to the experimental temperature by using electricity was longer than that required by using Ar plasma, which was usually 60min. When electricity was used, the peak difference in temperature between the beds was measured at about 200℃, while the difference attributed to Ar plasma heating was about 50℃. Further, Ar plasma heating resulted in even distribution of heat and steady operation of the fluidized bed. 

Abstract:A transparent simulating device was designed for investigating resident time of pyrolysis product of biomass in laminar entrained flow reactor. Resident time for char replacing pyrolysis product was measured using PIV (particle image velocimetry) at different gas flow rates and collection distances. Main gas flow rate, which measured at 1.0, 1.5, 2.0 and 2.5m3/h respectively, was determined by the similarity criteria that Reynolds number should be equal both in cold and hot flow field. Collection distances were 200, 250, 300 and 350mm. The results showed that the ratio of actual resident time of char and theoretical resident time of gas was proportional to Reynolds number, which meant the ratio of time and Reynolds number had one order functional relationship. Functional relation was different for different collection distances. It can therefore be concluded that when flow field is laminar, resident time of char can be calculated by functional relationship between ratio of time and Reynolds number. 

Abstract:The heat transfer mechanism between biomass particles and ceramic ball heat carriers was the subject of this study. The convective experiments between the ceramic balls and air, as opposed to heat transfer experiments involving the solid carriers and biomass particles and pyrolytic gaseous product, were conducted using the particles-separating apparatus. The convective heat transfer principle between one solid carrier and air as well as between biomass and solid carriers were discussed. According to the experimental data, the convective heat transfer coefficient of one ceramic ball was analyzed based on the theoretical and non-dimensional analytical methods, which were 291.3W/(m2?℃) and 200.3W/(m2?℃) respectively. The non-dimensional equations of biomass particles and ceramic balls were also determined via the heat balance analysis method and the non-dimensional equation, which were Nuc=176+0.079Rec and Nub=22.97+0.2251Reb respectively.

Abstract:In order to study the volatilization characteristics of biomass, a downward-flow tube reactor with a temperature control and measurement system was designed and fabricated. Corn stalk powder pyrolysis experiments were conducted and the experimental results showed that the reaction temperature could be controlled and measured precisely; the volatilized fraction of corn stalk powder increased nonlinearly with increased reaction temperature and residence time. 

Abstract:Micro-column, cortex and epidermis of corn stover were used to produce cellulases. The effects of solid-liquid rate (SL), fermentation time (FT), concentration of alkali oxide (AO) and pretreatment time (PT) on reducing sugar contents and filter paper activity (FPA) of the solution in the broth were investigated. Orthogonal tests were performed to optimize the saccharification conditions further. The results showed that the highest contents of reducing sugars were determined for the micro-column, cortex and epidermis of corn stover under the conditions of SL 1∶20/FT 5d/AO 1%/PT 3d, SL 1∶15/FT 5.5d/AO 1%/PT 3.5d and SL 1∶15/FT 5d/ AO 1%/PT 3d, respectively. The contents of reducing sugar reached 15.92%, 12.43% and 5.93%, and the highest saccharification percentages of the lignocelluloses reached 31.84%, 18.65% and 8.9%, respectively under the above conditions. The developing trend of filter paper activity was similar to the concentration of reducing sugar under lower concentrations of reducing sugar. 

Abstract:54.19mg/g。. According to the theory of microbial ecology, with sweet sorghum straw as the raw material, cellulose-decomposing fungi, which had high enzyme activity, were isolated from their natural habitat and screened. Meanwhile, the production conditions of cellulose enzyme were optimized based on the factors of temperature, initial pH value, and inoculation quantity, and the influence of these factors on enzyme activity was discussed. Taking Z15 as a test strain, optimization of production capacity of crude enzyme test was carried out, according to three factors, five-level orthogonal rotational regression test design, to investigate the effects on fermentation temperature, initial pH value and inoculation quantity. The yield of reducing sugar was taken as the indicators, and the impact on the target size about the three factors was analyzed. By calculating the analysis, the following results of the impact on the target was obtained: temperature was the first one, inoculation quantity was the last one and initial pH value was the middle. The optimum conditions for enzymatic hydrolysis were obtained: optimum temperature was 26.64℃, optimum initial pH value was 4.96, and optimum inoculation quantity was 5%, at this time reducing sugar content was 54.19mg/g. 

Abstract:Emulsified fuel was produced by mixing bio-oil pyrolyzed corn stalk with commercial No.0 diesel oil as well as surfactants using a homogenizer. The performances of bio-oil/diesel oil emulsified fuels with two different bio-oil/diesel oil ratios were tested on a ZS1110 diesel engine. The load characteristic curves of the diesel engine were determined. The experimental results showed that the effective thermal efficiency of two kinds of emulsified fuel was higher than that of the pure No.0 diesel oil. For emulsified fuel at bio-oil concentration of 15%, the specific fuel consumption was lower than that of No.0 diesel oil. However, there was often carbon deposition surrounding the diesel injector nozzle when using emulsified fuel.

Abstract:The preparation of biodiesel using microwave has received wide attention recently, and is summarized in terms of heterogeneous acid and basic catalysis transesterification. The heterogeneous catalyst process of biodiesel promoted by microwave has the advantages of rapid reaction, energy saving and environmental amity, and the resulting product is easy to separate from byproduct. Solid acid and base were selected as catalysts in the research. The transesterification reaction was finished in 10~30 min when promoted by microwave, and the conversion of transesterification reaction was comparable to or higher than that by traditional heating method. These catalysts can be reused several times.

Abstract:An automatic edge trim cutter machine of plant fiber tableware was studied based on designing parameters, technology route and key structure design calculation. The machine was designed with five forming stations driven by air cylinder, planetary gear structure, flexible profile modeling blade edge devices. The edge removing process was done during the turntable revolution and the product’s self-rotation. Pro/E software was used to simulate the 3-D entities of trim cutter machine. The working cycle was automatic closed-loop feedback controlled and validated in order to verify the accuracy of the machine. The results show that the trim cutter can be used in plant fiber tableware industry.

Abstract:The development of microalgae bioenergy industry could realize the combination of bioenergy production, environmental protection and CO2 emission reduction, which had important potential for achieving the sustainable development of human society. The advantages of microalgae bioenergy and the key technologies of microalgae bioenergy industrialization (including the screening of microalgae strain, large-scale cultivation and harvest, conversion and utilization of microalgae energy, and bio-refining of microalgae biomass) were introduced, and the appropriate model of microalgae bioenergy industry based on the current situation was explored. 

Abstract:1.7 d。The temperature distribution and variation of the ligule-shape petal, tubular petal and stem of individual and bunches of cut gerbera during vacuum cooling was measured by thermal infrared imaging. Relative fresh weight, stomatal conductivity and transpiration were analyzed during vase period. The results showed that the temperatures and three indexes were marked differently (P<0.05). The average pre-cooling end-temperature and vase life of individual flowers were 11.2℃ lower and 1.7 days longer than bunches of flowers respectively. This research has important value in the determination of pre-cooling end-temperature, the optimization of cooling processes and the evaluation of pre-cooling effect of different amounts of cut flowers. 

Abstract:Rehmanniae was chosen as the experimental material. The extraction method of catalpol in Rehmanniae was achieved via supersonic treatment followed by methanol extraction, and extraction time was decided thereafter. The results showed that degradation kinetics of catalpol in Rehmanniae during vacuum infrared radiation drying did not follow zero order or first order kinetics regulations. The degradation kinetics model of catalpol in Rehmanniae was established through introducing a parameter gT related to the radiation heater’s temperature, assuming that the parameters of degradation rate k agreed with Arrhenius equation. The test result showed that the model was a good fit for the experimental data.

Abstract:The effect of combining hot air with microwave vacuum to dry semi-dried lyeium, the effect of natural sun-drying, and the effect of microwave vacuum on fresh lyeium with different color-protecting methods were analyzed. Different drying methods, including a combination of hot-air and microwave vacuum, microwave vacuum, hot-air and natural sun drying were studied. The results proved that the quality of lyeium drying was improved by color protection. Drying in a microwave vacuum was better during the late drying phase rather than the early drying phase. The time to dry lyeium when combining the hot-air and microwave vacuum methods was 13.1h, which decreased from hot-air drying (34.9h) and natural sun drying (94.9h). The combination drying method produced better quality than the microwave vacuum, but the result was similar to the method of hot-air drying. The reservation rate of lyeium barbarum polysaccharide was very close to that of hot-air drying and natural solar drying.

Abstract:A simple method for online measurement of drying process of fruits and vegetables was explored. Relative permittivities of an apple sample and a mixed sample composed of air and apple were measured by LCR meter and matching electrode during a hot air drying process. Then, relation equations between permittivity and relative water content, as well as between permittivity and drying rate, were respectively established. It was found that relative permittivities and drying characteristics were significantly correlated, and correlations between the dielectric constant and the drying characteristics of the mixture were stronger than that of only the apple sample. Conclusions indicated that detecting the moisture content of fruits and vegetables could be more readily achieved with measuring mixed samples instead of only the material itself.

Abstract:2阶段降到0.116%/min，第3阶段为0.039%/min。In order to improve solar drying efficiency, forage drying characteristics using low temperature were studied. In the condition of low temperature, lucerne was dried using a dryness test-bed. Through testing and analysis, changes in lucerne moisture content, weight, and surface temperature during the course of lucerne drying were determined. The results showed that the surface temperature of heating during the first stage of drying had the fastest decline to 0.43%/min water content. When the surface temperature was moderate, water drop speed gradually slowed to 0.116%/min; and the water content decline in the third stage was 0.039%/min.

Abstract:During potato starch processing, a large volume of high-content organic acid wastewater was produced. This could result in serious environmental pollution if the wastewater was directly discharged. As a result, the treatment of potato starch wastewater has become a subject of increasing scrutiny. Various domestic and international methods for treating potato starch wastewater were introduced.

Abstract:0.2%，废水pH值为9.0时，COD去除率达56.24%。Polymerization aluminum chloride (PAC) and cationic polyacrylamide (CPAM) were used to treat potato starch wastewater. The cleaning efficiency of the chemical oxygen demand (COD) in the wastewater was also studied by changing the experimental conditions. In the orthogonal test, the optimal conditions were as follows: PAC addition 0.2%, CPAM addition 0.1%, and reaction pH value 9.0. The removal rate of COD was 56.24%. 

Abstract:DPPH自由基的EC50值为0.155g/（100mL）。Protease screening was studied to prepare potato antioxidant peptide using the enzymolysis method. With potato dregs as the raw material and the scavenging rate of hydrolysate to the DPPH radical as an index, neutral protease was screened out from the following six kinds of protease: papain, flavor protease, neutral protease, alkaline protease, trypsin and pepsin. The optimum hydrolysis conditions obtained by the experiments were substrate concentration 4 g/(100mL), 7% enzyme-substrate ratio, pH value 8.0, 50°C and 90min reaction time. After being diluted 20 times, the scavenging rate of hydrolysate liquid to the DPPH radical reached 72%. The EC50 value of hydrolysate scavenging the DPPH radical was 0.155 g/(100mL).

Abstract:790.71 g?mm，弹性为38.18g。The effects of noodle improvers, composed of guar gum, starch phosphate ester, and trimeric sodium phosphate, on the toughness and springiness of the noodle were investigated with response surface methodology. The mathematical model was obtained and the optimum ratio of noodle improvers was: guar gum 0.7%, starch phosphate ester 5.50%, trimeric sodium phosphate 0.15%. Under these conditions, the toughness and springiness of the noodle were 790.71g?mm and 38.18g, respectively.

Abstract:The effects of pretreatment process on the micro-structure of rapeseed and the presence state of rapeseed oil in cells were researched. The cell ultra-structures of rapeseed after flaking, cooking, expanding and pressing were analyzed by transmission electron microscope (TEM). Rapeseed cell was extruded obviously by flaking process and it turned from circle shape to ellipse shape. After flaking the cell wall was partly broken and a few lipid droplets were gathered together. A few cell wall was destroyed and some lipid droplets came closely and agglomerated into larger particles by cooking. Cell wall was destroyed totally and the cytoplasm was extruded out by expanding. Most lipid droplets came close enough to agglomerate into larger particles and fully leaked out by expanding. The shape and structure of rapeseed cell were devastated by pressing. It was showed that expanding was more suitable for broking the structure of the cell than cooking and it would be the best way for oil making.

Abstract:Natural microflora, yeast and mold, E.coli, and Salmonella in fresh raspberry juice were taken as the research objects for discussing the sterilizing effect of UHP. It showed that the higher the pressure was, the better the sterilization effect would be; with increased holding pressure time，the lethal effect on these microorganisms became stronger. At room temperature (25℃) and with the pressure of 200MPa, E. coli was totally killed when the holding pressure time was 5min. At the pressure of 300MPa and holding pressure time of 15min, Salmonella was totally killed. At pressure of 400MPa and holding pressure time of 15min, mold and yeast were totally killed. When the pressure was 600MPa and the holding pressure time was 25min, the micro-organisms in the juice were not completely killed; however, the total number of colonies could be reduced below 10cfu/mL, which met the national food hygienic standard of China (NFHSC) criterion.

Abstract:In order to raise the mechanical properties of vegetable paper used for packaging, the entire or sectioned leaf cut-off celery was macerated to different degrees and two samples of leaf cut-off celery paper were prepared under the condition of middle scale production. Fiber analyses were given by Swedish L&W fiber tester. The microstructure characteristics of leaf cut-off celery paper were presented through photographs from the Olympus microscope and micro-photograph analyzer. Mechanical properties were tested under standard conditions and their variation was analyzed. Results show the differences in tensile strength is 1.323 times between two samples. Compared with leafed celery paper, the tensile strength of leaf cut-off celery paper is generally 2.326 times greater and leaf cut-off celery paper also has better break percentage elongation.

Abstract:8.3。This automatic poultry eviscerator was designed based on imported advanced poultry-eviscerating technology. The machine can eviscerate all poultry entrails at once, with the exception of the lung and kidney. The main parts of this prototype were introduced, including chain wheel system, eviscerating manipulator, cam mechanism and height adjustment mechanism etc. Processing tests were done to measure the main performance indexes of the prototype. The results showed that the optimum distance between the shackle bottom and the manipulator extremity was 310~320mm for a duck size range of 2.5～3.5kg (live weight). The percent of remaining entrails was 5.6%. The liver was easy to damage and the entrails damage mark was 8.3. 

Abstract:The velocity and pressure fields of the fluid in the twin-screw extruder were studied using FEM. The specific energy consumption of various operations was obtained by post-processing. The experiment was designed using the rotatable and central composite method. The reason for the existing differences between the simulation and experimental results was analyzed, and the simulation results were corrected. The BP algorithm was trained based on the simulation and experimental results. The extruding system model of twin-screw extruder was built, and could be used to quantitatively predict the specific energy consumption of the extruder.

Abstract:Based on the analysis of feed grinder working principles and the influence of hammer form changing on the working efficiency during the hammer wear passivating process, the hammer self-sharpening enhanced process was put forward. The gas carburizing process was used to strengthen the two sides of the hammer, and the seepage treatment was used to strengthen the side surface and axle hole of the hammer. With the appropriate heat treatment, the metallographic structures of the two edges and the middle part were different. As a result, the hardness of the hammer edges was much greater than that of the middle part. And the production test confirmed that the section corner could not be formed during the hammer’s working process. The frontal attack on materials and edges cutting of the hammer were maintained.

Abstract:A bivariable control system that combined GPS and GPRS was designed as the variable rate fertilizer embedded solutions, and the information platform based on ARM and DSP dual-CPU architecture was developed. Based on ARM9 and WinCE support the graphical user interface and touch operation, the host system was able to achieve information input and reflect the real-time operating status of the fertilization and seed production process. Based on DSP/BIOS real-time operating system, the slave system could implement the opening and revolution motor servo control of fertilizing and seeding. The system hardware and software structure, which has good scalability and real-time flexibility, was depicted in detail. The test results showed that the system could achieve fast and accurate fertilizing and seeding precision delivery.

Abstract:0.18m以内。A velocity adaptive navigation controller was designed. On the harvester vision navigation experimental platform, a double closed-loop control structure, which used PD control mode, was put forward and the navigational deviation was set up according to the deviation of the heading angle and lateral position of the structure. The relationships between the control parameters of the control gain K and the control period T, and the harvester speed v were experimentally obtained. The computing method of inner closed loop control was given based on the method of one dynamic calibration for the rear wheel at mid-position-voltage. The test results on road and in wheat field showed that the combine harvester could trace the navigation line at different speeds, and on the road, the maximal tracing error was 0.05m. In wheat fields, the change of harvesting width was in 0.18m during the working speed.

Abstract:As the cucumber harvesting robot works in the non-structure condition, the structure and movement of the manipulator directly determines operating space and picking success. According to the specific cucumber cultivation, the manipulator was designed and its structure parameters were optimized based on the method of the parameters optimization. With the D-H kinematic model, the coordinate transformation was achieved between the Articulation and the Cartesian space, and the Jacobian matrix of velocity was derived. Besides, the model was built in the Articulation space for planning path by means of cubic polynomial interpolation. All the parameters optimized was simulated with Matlab, and the simulation results showed that the harvesting manipulator could reach the positions of 90.5% of the cucumbers in the workspace, moreover, it could move smoothly. 

Abstract:500粒/min。A sorting system for maize haploid kernels marked with the Navajo label was designed. It consisted of a seed transmission unit, an image acquisition and processing unit, a sorting-unloading unit and a system control unit. The image acquisition and processing unit identified the haploid kernels according to the color features on maize embryo and the top of maize endosperm. Then it sent the identification information results to the system control unit. The system control unit, which controlled the motion of the seeds transmission unit and the mechanical arm of the sorting-unloading unit, opened the solenoid valves which connected to the mechanical arm. The system separated the heterozygote kernels from the haploid kernels using air-suction and achieved a sorting speed of 500 kernels per minute.

Abstract:Field parcel images consist of multiple target regions where different field objects are always interfered each other. As a result, segmentation and feature extraction of the field parcel image are very difficult. Aiming at that, two algorithms based on edge and region were used to process field parcel images photographed by an aerial camera. The results showed that the algorithm of image edge segmentation based on differential operators could effectively detect the edge of the field parcel, but enlarged the noise of image; the algorithm of image region segmentation based on threshold could effectively remove the noise from field parcel image.

Abstract:There are disadvantages in agricultural equipment testing systems, such as difficulties with wiring, limited transmission and the problematic expansion. Yet with embedded technology and virtual instruments, the development of various wireless transmission modes for agricultural equipment, which related to parameters measurement and control systems, improved the overall reliability. Embedded technology and virtual instruments addressed testing in the field, the single function of traditional testing instruments, the lack intelligent data processing, and so on. The core technology integrated intelligent agricultural equipment by using similarity parameters acquisition, and wireless transmission platform development, in addition to computer software platforms for receiving and handling wireless data transmission. The quality of agricultural equipment and automation level was effectively improved. 

Abstract:Acoustic frequency technology can promote the growth of plants in horticulture, but the promotion mechanism is not clear. Therefore, the method of spontaneous acoustic frequency (SAF) measurement was explored, and the spontaneous spectrum of cucumber seedlings was examined. Using a laser PDV-100 vibrometer, the SAF of cucumber seedlings in different locations (main vein, mesophyll and stem) and different environments (light intensity changes and drought stress) was measured in a semi-anechoic room by non-contact measurement. The power spectrum and autocorrelation of SAF were analyzed and the spontaneous spectral characteristics of cucumber seedlings were obtained. The results showed that the basic frequency of cucumber seedlings’ SAF was in 4.98~5.86 Hz and the spontaneous acoustic signal variations under different environments in the three parts of the cucumber were consistent.

Abstract:3g/L。Automatic, quality-grading equipment was designed for grain purchasing, which could detect and grade grain impurities and moisture using the capacitance measurement method, and bulk density using the vacuum negative pressure method. Experimental results showed that after the separation of impurities, the grain purity was 99.5%，the repeatability error of impurity separation was less than 0.3%, moisture error was within ±0.5%, the repeatability error of moisture was less than 0.2%, and the repeatability error of bulk density was less than 3g/L.

Abstract:At present, the standard system of agricultural mechanization in China faces some problems such as loose-standard, inadequate integrity, unbalanced development and so on. Based on the investigation and analysis of the existing agricultural mechanization standard system, this paper mainly considered the necessity of the agricultural mechanization standard system development. The 3-D framework consisting of field, product, type of standard of agricultural mechanization was designed by using analytic hierarchy process and 3-D structural method. 