The optimized nitrogen fertilization location differs in different rice-growing regions. We optimized nitrogen deep-point application in root-growing zone(NARZ) for transplanted rice in subtropical China. Field plot...The optimized nitrogen fertilization location differs in different rice-growing regions. We optimized nitrogen deep-point application in root-growing zone(NARZ) for transplanted rice in subtropical China. Field plot experiments were conducted over two years(2014–2015) in a double-rice cropping system to evaluate the effects of nitrogen(N) fertilizer location on grain yield and N use efficiency(NUE). Four different nitrogen deep-point application methods(DN) were compared with traditional broadcast application(BN) using granular urea. The results showed that grain yield, recovery efficiency of N(REN), agronomic efficiency of N(AEN), and partial factor productivity of N(PFP_N) significantly increased 10.3–63.4, 13.7–56.7, 24.7–201.9 and 10.2–63.4%, respectively, in DN treatment compared to BN, respectively. We also find that DN treatments increased grain yield as well as grain N content, and thus grain quality, in comparison with conventional BN treatment. Correlation analysis indicated that significant improvement in grain yield and NUE mainly resulted from increases in productive panicle number and grain N content. In our proposed NARZ method, granular urea should be placed 0 to 5 cm around the rice seeding at a 12-cm depth druing rice transplanting. In NARZ, balanced application of N, P and K further improved grain yield and NUE over treatments with a single N deep-point application. High N uptake by the rice plant did not cause significant soil fertility depletion, demonstrating that this method could guarantee sustainable rice production.展开更多
The sensor system is one of the modern and important methods of irrigation management in arid and semi-arid areas, which is water as the limiting factor for crop production. The study was applied for 2016 and 2017 sea...The sensor system is one of the modern and important methods of irrigation management in arid and semi-arid areas, which is water as the limiting factor for crop production. The study was applied for 2016 and 2017 seasons out in Al-Yousifya, 15 km Southwest of Baghdad. A study was conducted to evaluate coefficient uniformity, uniformity distribution and application efficiency for furrow, surface drip and subsurface drip irrigation methods and it was (98, 97 and 89)% and (97, 96 and 88)% for 2016 and 2017 seasons;respectively. And control the volumetric moisture content according to the rhizosphere depth for depths of 10, 20 and 30 cm by means of the sensor system. The results indicated that the height consumptive water use of furrow 707.91 and 689.69 mm<span style="white-space:nowrap;">·</span>season<sup>-1</sup> and the lowest for subsurface drip with emitter deep at 20 cm 313.93 and 293.50 mm<span style="white-space:nowrap;">·</span>season<sup>-1</sup> for 2016 and 2017 seasons;respectively. As well, the highest value of water use efficiency for subsurface in drip irrigation at a depth of 20 cm, was 2.71 and 2.99 kg<span style="white-space:nowrap;">·</span>m<sup>-3</sup> and the lowest value for furrow irrigation was 1.12 and 1.20 kg<span style="white-space:nowrap;">·</span>m<sup>-3</sup> for the 2016 and 2017 seasons;respectively.展开更多
Metamorphic In0.55Ga0.45P/In0.06Ga0.94As/Ge triple-junction (3J-MM) solar cells are grown on Ge (100) sub- strates via metal organic chemical vapor deposition. Epi-structural analyses such as high resolution x-ray...Metamorphic In0.55Ga0.45P/In0.06Ga0.94As/Ge triple-junction (3J-MM) solar cells are grown on Ge (100) sub- strates via metal organic chemical vapor deposition. Epi-structural analyses such as high resolution x-ray diffrac- tion, photoluminence, cathodoluminescence and HRTEM are employed and the results show that the high crystal quality of 3J-MM solar cells is obtained with low threading dislocation density of graded buffer (an average value of 6.8× 10^4/cm2). Benefitting from the optimized bandgap combination, under one sun, AM0 spectrum, 25℃ conditions, the conversion efficiency is achieved about 32%, 5% higher compared with the lattice-matched In0.49Ga0.51P/In0.01Ga0.99As/Ge triple junction (3J-LM) solar cell. Under 1-MeV electron irradiation test, the degradation of the EQE and I-V characteristics of 3J-MM solar cells is at the same level as the 33-LM solar cell. The end-of-life efficiency is -27.1%. Therefore, the metamorphic triple-junction solar cell may be a promising candidate for next-generation space multi-junction solar cells.展开更多
[Objective] Application of P and K was not reasonable in southwest rice producing area, with no effective method for guiding application of P and K. This study aimed to conduct experiments with the same N application ...[Objective] Application of P and K was not reasonable in southwest rice producing area, with no effective method for guiding application of P and K. This study aimed to conduct experiments with the same N application and different P and K application in different ecological points, to explore a scientific and efficient management method of P and K nutrients and provide guidance for application of P and K in rice production. [Method] Hybrid rice Chuanxiang9838 was used as experimental material to study the relationship among application amount of P and K, utilization rates of P and K, rice yield and rice quality in seven ecological points of four provinces (municipalities) including Sichuan, Chongqing, Yunnan and Guizhou. The application amount per hectare of P was 37.5, 75, 112.5 and 150 kg, respectively; the application amount per hectare of K was 45, 135 and 180 kg, respectively. A total of 10 treatments were set for split-plot design with three replications. [Result] Yield of Chuanxiang9838 significantly varied in different experimental locations and under different levels of P and K, interaction of ecological point and different P and K treatments varied significantly. Yield had reached the maximum in ecological point of Yunnan Binchuan and in treatment with application of N 150 kg P 75 kg K 90 kg. Efficient utilization rates of P and K varied in each ecological point, efficient application amount of P and K in Sichuan Dongpo, Sichuan Luxian, Guizhou Xiaohe and Chongqing Yongchuan was the same, while that in Sichuan Guanghan, Sichuan Zhongjiang and Yunnan Binchuan was different. The main objective of high-yield rice production was to increase the number of effective panicles per hectare and seed setting rate. Rice quality was clustered into 2 categories by locations and 6 categories by treatments. [Conclusion] Prediction models of efficient application of P and K in rice production were established, which provided guidance for high-yield rice production and rational and efficient utilization of P and K in southwest rice area.展开更多
A macro scale survey was performed to investigate the content of soil available nitrogen (N) and its spatial distribution in the main vegetable production areas of the Pearl River Delta.Preliminary enrichment-deficien...A macro scale survey was performed to investigate the content of soil available nitrogen (N) and its spatial distribution in the main vegetable production areas of the Pearl River Delta.Preliminary enrichment-deficient index of available N was then developed,which was a base for increasing fertilizer application efficiency and vegetable yield as well as for constructing soil testing and fertilizing formula.In general,most of the vegetable growth areas in Pearl River Delta were N-deficient or medium-N-deficient.There was 30%-62% increase in yield of Chinese cabbage on the N-deficient soil after application of N; when soil available N content was less than 145 mg/kg,the yield increased with application of N fertilizer at a rate of 60-70 kg/hm2.展开更多
With increasing water shortage resources and extravagant nitrogen application, there is an urgent need to optimize irrigation regimes and nitrogen management for winter wheat(Triticum aestivum L.) in the North China...With increasing water shortage resources and extravagant nitrogen application, there is an urgent need to optimize irrigation regimes and nitrogen management for winter wheat(Triticum aestivum L.) in the North China Plain(NCP). A 4-year field experiment was conducted to evaluate the effect of three irrigation levels(W1, irrigation once at jointing stage; W2, irrigation once at jointing and once at heading stage; W3, irrigation once at jointing, once at heading, and once at filling stage; 60 mm each irrigation) and four N fertilizer rates(N0, 0; N1, 100 kg N ha-(-1); N2, 200 kg N ha-(-1); N3, 300 kg N ha-(-1)) on wheat yield, water use efficiency, fertilizer agronomic efficiency, and economic benefits. The results showed that wheat yield under W2 condition was similar to that under W3, and greater than that under W1 at the same nitrogen level. Yield with the N1 treatment was higher than that with the N0 treatment, but not significantly different from that obtained with the N2 and N3 treatments. The W2 N1 treatment resulted in the highest water use and fertilizer agronomic efficiencies. Compared with local traditional practice(W3 N3), the net income and output-input ratio of W2 N1 were greater by 12.3 and 19.5%, respectively. These findings suggest that two irrigation events of 60 mm each coupled with application of 100 kg N ha-(–1) is sufficient to provide a high wheat yield during drought growing seasons in the NCP.展开更多
[Objective]The paper was to screen a new ideal sustained-release,long-lasting and low-toxic pesticide and convenient and efficient pesticide application technology for controlling Ceratovacuna lanigera and Baliathrips...[Objective]The paper was to screen a new ideal sustained-release,long-lasting and low-toxic pesticide and convenient and efficient pesticide application technology for controlling Ceratovacuna lanigera and Baliathrips serratus. [Method]2% Imidacloprid GR were selected and applied in the soil for field efficacy trial. [Result] The optimum dosage of 2% imidacloprid GR was 30 kg/hm^2( active ingredient 600 g),which can be mixed with fertilizer( 30 kg pesticide and 40-80 kg fertilizer per hm^2) once combined with sugarcane planting management or big ridging during February and June. The control effects against C. lanigera and B. serratus could be more than 98. 2% and 81. 1%,respectively. The actual yield and sugar content in various pesticide treatments were increased by 33 390 kg/hm^2 and 6. 6% respectively compared to blank control. [Conclusion]2% imidacloprid GR has good control effects on C. lanigera and B. serratus. It is a new pesticide with ideal sustained-release,long-lasting and low-toxin effects against C. lanigera and B. serratus. Therefore,it could be used alternatively with other pesticides,to delay production and development of drug resistance.展开更多
We present an efficient three-dimensional coupled-mode model based on the Fourier synthesis technique. In principle, this model is a one-way model, and hence provides satisfactory accuracy for problems where the forwa...We present an efficient three-dimensional coupled-mode model based on the Fourier synthesis technique. In principle, this model is a one-way model, and hence provides satisfactory accuracy for problems where the forward scattering dominates. At the same time, this model provides an efficiency gain of an order of magnitude or more over two-way coupled-mode models. This model can be applied to three-dimensional range-dependent problems with a slowly varying bathymetry or internal waves. A numerical example of the latter is demonstrated in this work. Comparisons of both accuracy and efficiency between the present model and a benchmark model are also provided.展开更多
[Objective] The paper was to provide scientific basis for popularization and application of 70% Thiamethoxam ZF. [Method] 70% Thiamethoxam ZF was selected and applied in the soil for controlling Ceratovacuna lanigera ...[Objective] The paper was to provide scientific basis for popularization and application of 70% Thiamethoxam ZF. [Method] 70% Thiamethoxam ZF was selected and applied in the soil for controlling Ceratovacuna lanigera Zehntner and Baliathrips serratus Kobus. [ Result ] 70% Thiamethoxam ZF had good con-rol effect against C. lanigera and B. serratus. The optimum dosage of 70% Thiamethoxam ZF was 450 g/hm^2 (effective ingredients 315 g). 70% Thiamethoxam ZF ( dosage per hm^2 ) mixed with the regular fertilizer ( dosage per hm^2 ) should be applied together in sugarcane planting and management from February to June. The control effects against C. lanigera and B. serratus were above 98.4% and 82.9% respectively. The actual yield and sugar content were increased by more than 34 290 kg/hm^2 and 6.8% respectively compared to blank control. [ Conclusion] 70% Thiamethoxam ZF was a new ideal pesticide with characteristics of sustained- release, long-lasting and low-toxic for controlling C. lanigera and B. serratus, and should be applied widely in the sugarcane planting area.展开更多
The number of therapeutic monoclonal antibodies used in clinical trials has recently increased dramatically, leading to the development of optimized downstream purification processes[1]. Staphylococcal protein A (SPA...The number of therapeutic monoclonal antibodies used in clinical trials has recently increased dramatically, leading to the development of optimized downstream purification processes[1]. Staphylococcal protein A (SPA), a cell-wall protein of Staphylococcus aureus, has been developed as a universal ligand for immunoglobulin G (IgG) purification because it binds specifically to the Fc portion of the IgG molecule of many mammals[2]. However, certain characteristics of SPA severely restrict the advancement of the antibody industry.展开更多
Considering the high-quality requirements related to agricultural crop production,the collaborative operation and application influence of sprinkler drip irrigation is an important issue in precision agriculture.The o...Considering the high-quality requirements related to agricultural crop production,the collaborative operation and application influence of sprinkler drip irrigation is an important issue in precision agriculture.The objective of this review is to give a comprehensive demonstration focusing on the subject of collaborative operation and application influence of sprinkler drip irrigation,by using a set of comparative analysis and literature bibliometric maps,therefore the sprinkler drip irrigation quality considering actual influential factors could be determined and analyzed.This review establishes on a broad spectrum of agricultural drip irrigation performance,throughout its whole procedure of collaborative monitoring,irrigation scheduling,application efficiency,and environmental influence,covering such aspects as soil physicochemical quality,irrigation scheduling,water resource redistribution,crop productivity,tillage management,climate adaptation,and environmental monitoring,etc.This review indicates that,the irrigation efficiency and drip infiltration quality of soil field can be planned precisely and allocated reasonably by sprinkler drip irrigation,which has extraordinary infiltration capability and enables much better performance,than that of other ordinary irrigation approaches in accuracy,stability,regularity,and efficiency.Thereafter,the investigation on the collaborative operation and application influence of sprinkler drip irrigation can be used to ensure the infiltration uniformity of moisture distribution,and then the high-quality requirements of practical irrigation performance can be met,too.This systematic review facilitates the productive soil-moisture-environment management for precision irrigation and agricultural production.展开更多
Improving pesticide application efficiency is increasingly important in orchard spraying.In this study,a laser-scanning system was designed to acquire gridding volumes of a tree to quantify the geometry characteristic...Improving pesticide application efficiency is increasingly important in orchard spraying.In this study,a laser-scanning system was designed to acquire gridding volumes of a tree to quantify the geometry characteristics of the tree canopy in real-time.A laser-scanning sensor mounted on a linear guide was utilized to measure the structure of a target tree canopy.A computer was used to receive measurement data from the laser scanner and obtain the movement distance of the laser-scanning sensor from a controller.An algorithm written with VC#program was designed to calculate gridding volumes of trees by recognizing valid measurement data from the laser scanner.Laboratory evaluations were conducted on three kinds of regular objects,and the maximum relative errors of section volumes of the cuboid,triangular prism and cylinder objects were 3.3%,7.9%and 9.4%,respectively,which illustrated that the algorithm could calculate the section volumes in different parts of the objects with high accuracy.A conifer tree and an apple tree were chosen to verify detecting accuracy of the laser-scanning system at variable speeds and grid sizes.The variation coefficients of total volumes for each kind of the tree were 0.078 and 0.041,respectively,which indicated that the laser-scanning system could be applied to provide the gridding volumes of different canopy densities in real-time with good reliability for guiding a variable-rate sprayer.展开更多
To improve the precision spraying strategy and reduce excessive pesticide application in orchards,an air-assisted sprayer integrated with a laser-scanning system was developed to realize the toward-target variable-rat...To improve the precision spraying strategy and reduce excessive pesticide application in orchards,an air-assisted sprayer integrated with a laser-scanning system was developed to realize the toward-target variable-rate spraying.In the spray control system,a method of calculating canopy gridding volumes was designed to ensure that the canopy was divided into a uniform grid size,a variable-rate spray model was used in the flow rate decision software to control the spray output according to the canopy gridding volumes and travel speed,and a method of saving and accessing spray data was used to control the spray delay.The effects of different grid sizes and travel speeds on the spray performance were evaluated by quantifying spray coverage uniformity inside tree canopies.The results showed that spray coverage uniformity declined with increasing grid width from 0.14 to 0.28 m although the mean spray coverage on each target location showed no significant differences.Additionally,there were no significant variations in mean spray coverage at speeds of 1.0,1.2 and 1.4 m/s for a tested tree of 1.6 m width and at any experimental speeds for a tested tree of 1.3 m width,which indicated that the variable-rate sprayer could provide good spray coverage uniformity under various travel speeds with a canopy size limitation.Compared with the same sprayer without the variable-rate spray function,the intelligent sprayer prototype realized effective toward-target spraying and avoided overspraying while providing sufficient spray coverage.展开更多
Carbon nanotube field effect transistor(CNFET) shows lower threshold voltage and smaller leakage current in comparison to its CMOS counterpart. In this paper, two kinds of CNFET-based rectifiers, full-wave rectifier...Carbon nanotube field effect transistor(CNFET) shows lower threshold voltage and smaller leakage current in comparison to its CMOS counterpart. In this paper, two kinds of CNFET-based rectifiers, full-wave rectifiers and voltage doubler rectifiers are presented for biomedical implantable applications. Based on the standard 32 nm CNFET model, the electrical performance of CNFET rectifiers is analyzed and compared. Simulation results show the voltage conversion efficiency(VCE) and power conversion efficiency(PCE) achieve 70.82% and 72.49% for CNFET full-wave rectifiers and 56.60% and 61.17% for CNFET voltage double rectifiers at typical 1.0 V input voltage excitation, which are higher than that of CMOS design. Moreover, considering the controllable property of CNFET threshold voltage, the effect of various design parameters on the electrical performance is investigated.It is observed that the VCE and PCE of CNFET rectifier increase with increasing CNT diameter and number of tubes. The proposed results would provide some guidelines for design and optimization of CNFET-based rectifier circuits.展开更多
基金financially supported by the National Basic Research Program of China(2013CB127401)the National Natural Science Foundation of China(41401258)+1 种基金the Natural Science Foundation of Jiangsu Province,China(BK20131044)the Natural Science Foundation of Jiangxi Province,China(20142BAB214005)
文摘The optimized nitrogen fertilization location differs in different rice-growing regions. We optimized nitrogen deep-point application in root-growing zone(NARZ) for transplanted rice in subtropical China. Field plot experiments were conducted over two years(2014–2015) in a double-rice cropping system to evaluate the effects of nitrogen(N) fertilizer location on grain yield and N use efficiency(NUE). Four different nitrogen deep-point application methods(DN) were compared with traditional broadcast application(BN) using granular urea. The results showed that grain yield, recovery efficiency of N(REN), agronomic efficiency of N(AEN), and partial factor productivity of N(PFP_N) significantly increased 10.3–63.4, 13.7–56.7, 24.7–201.9 and 10.2–63.4%, respectively, in DN treatment compared to BN, respectively. We also find that DN treatments increased grain yield as well as grain N content, and thus grain quality, in comparison with conventional BN treatment. Correlation analysis indicated that significant improvement in grain yield and NUE mainly resulted from increases in productive panicle number and grain N content. In our proposed NARZ method, granular urea should be placed 0 to 5 cm around the rice seeding at a 12-cm depth druing rice transplanting. In NARZ, balanced application of N, P and K further improved grain yield and NUE over treatments with a single N deep-point application. High N uptake by the rice plant did not cause significant soil fertility depletion, demonstrating that this method could guarantee sustainable rice production.
文摘The sensor system is one of the modern and important methods of irrigation management in arid and semi-arid areas, which is water as the limiting factor for crop production. The study was applied for 2016 and 2017 seasons out in Al-Yousifya, 15 km Southwest of Baghdad. A study was conducted to evaluate coefficient uniformity, uniformity distribution and application efficiency for furrow, surface drip and subsurface drip irrigation methods and it was (98, 97 and 89)% and (97, 96 and 88)% for 2016 and 2017 seasons;respectively. And control the volumetric moisture content according to the rhizosphere depth for depths of 10, 20 and 30 cm by means of the sensor system. The results indicated that the height consumptive water use of furrow 707.91 and 689.69 mm<span style="white-space:nowrap;">·</span>season<sup>-1</sup> and the lowest for subsurface drip with emitter deep at 20 cm 313.93 and 293.50 mm<span style="white-space:nowrap;">·</span>season<sup>-1</sup> for 2016 and 2017 seasons;respectively. As well, the highest value of water use efficiency for subsurface in drip irrigation at a depth of 20 cm, was 2.71 and 2.99 kg<span style="white-space:nowrap;">·</span>m<sup>-3</sup> and the lowest value for furrow irrigation was 1.12 and 1.20 kg<span style="white-space:nowrap;">·</span>m<sup>-3</sup> for the 2016 and 2017 seasons;respectively.
基金Supported by the Grand from Tianjin Little Giant Fund under Grant No 14ZXLJGX00400the Tianjin Science and Technology Support Plan under Grant No 16YFZCGX00030
文摘Metamorphic In0.55Ga0.45P/In0.06Ga0.94As/Ge triple-junction (3J-MM) solar cells are grown on Ge (100) sub- strates via metal organic chemical vapor deposition. Epi-structural analyses such as high resolution x-ray diffrac- tion, photoluminence, cathodoluminescence and HRTEM are employed and the results show that the high crystal quality of 3J-MM solar cells is obtained with low threading dislocation density of graded buffer (an average value of 6.8× 10^4/cm2). Benefitting from the optimized bandgap combination, under one sun, AM0 spectrum, 25℃ conditions, the conversion efficiency is achieved about 32%, 5% higher compared with the lattice-matched In0.49Ga0.51P/In0.01Ga0.99As/Ge triple junction (3J-LM) solar cell. Under 1-MeV electron irradiation test, the degradation of the EQE and I-V characteristics of 3J-MM solar cells is at the same level as the 33-LM solar cell. The end-of-life efficiency is -27.1%. Therefore, the metamorphic triple-junction solar cell may be a promising candidate for next-generation space multi-junction solar cells.
基金Supported by Project of Rice Industry Technology System ConstructionGrain Production Technology Engineering Project200903002 Project~~
文摘[Objective] Application of P and K was not reasonable in southwest rice producing area, with no effective method for guiding application of P and K. This study aimed to conduct experiments with the same N application and different P and K application in different ecological points, to explore a scientific and efficient management method of P and K nutrients and provide guidance for application of P and K in rice production. [Method] Hybrid rice Chuanxiang9838 was used as experimental material to study the relationship among application amount of P and K, utilization rates of P and K, rice yield and rice quality in seven ecological points of four provinces (municipalities) including Sichuan, Chongqing, Yunnan and Guizhou. The application amount per hectare of P was 37.5, 75, 112.5 and 150 kg, respectively; the application amount per hectare of K was 45, 135 and 180 kg, respectively. A total of 10 treatments were set for split-plot design with three replications. [Result] Yield of Chuanxiang9838 significantly varied in different experimental locations and under different levels of P and K, interaction of ecological point and different P and K treatments varied significantly. Yield had reached the maximum in ecological point of Yunnan Binchuan and in treatment with application of N 150 kg P 75 kg K 90 kg. Efficient utilization rates of P and K varied in each ecological point, efficient application amount of P and K in Sichuan Dongpo, Sichuan Luxian, Guizhou Xiaohe and Chongqing Yongchuan was the same, while that in Sichuan Guanghan, Sichuan Zhongjiang and Yunnan Binchuan was different. The main objective of high-yield rice production was to increase the number of effective panicles per hectare and seed setting rate. Rice quality was clustered into 2 categories by locations and 6 categories by treatments. [Conclusion] Prediction models of efficient application of P and K in rice production were established, which provided guidance for high-yield rice production and rational and efficient utilization of P and K in southwest rice area.
基金supported by the Special Financial Support Program on Agriculture Research of Public Welfare Industry (Grant No. nyhyzx07-007-6)Special Fund for the Guangdong Modern Agriculture Industrial System Construction(Guangdong Agriculture 2009-380)+2 种基金Guangdong Agriculture Brainstorm Project ( Grant No. 2008B021000045, 2009B 020202003)the National Science and Technology Support Program (Grant No.2007BAD89B14)Agriculture Brainstorm Project of Panyu District, Guangzhou, Guangdong province(Grant No.2010-Z-82-1)
文摘A macro scale survey was performed to investigate the content of soil available nitrogen (N) and its spatial distribution in the main vegetable production areas of the Pearl River Delta.Preliminary enrichment-deficient index of available N was then developed,which was a base for increasing fertilizer application efficiency and vegetable yield as well as for constructing soil testing and fertilizing formula.In general,most of the vegetable growth areas in Pearl River Delta were N-deficient or medium-N-deficient.There was 30%-62% increase in yield of Chinese cabbage on the N-deficient soil after application of N; when soil available N content was less than 145 mg/kg,the yield increased with application of N fertilizer at a rate of 60-70 kg/hm2.
基金supported by the National Key Research and Development Program of China (2016YFD0300808)the National Key Technologies R&D Program of China during the 12th Five-Year Plan period (2013BAD05B02)+2 种基金the National Natural Science Foundation of China (31571612 and 31100191)the Science and Technology Service Network Initiative of Chinese Academy of Sciences (KFJ-STSZDTP-001)the Hebei Key Research and Development Program, China (15226407D and 17227006D)
文摘With increasing water shortage resources and extravagant nitrogen application, there is an urgent need to optimize irrigation regimes and nitrogen management for winter wheat(Triticum aestivum L.) in the North China Plain(NCP). A 4-year field experiment was conducted to evaluate the effect of three irrigation levels(W1, irrigation once at jointing stage; W2, irrigation once at jointing and once at heading stage; W3, irrigation once at jointing, once at heading, and once at filling stage; 60 mm each irrigation) and four N fertilizer rates(N0, 0; N1, 100 kg N ha-(-1); N2, 200 kg N ha-(-1); N3, 300 kg N ha-(-1)) on wheat yield, water use efficiency, fertilizer agronomic efficiency, and economic benefits. The results showed that wheat yield under W2 condition was similar to that under W3, and greater than that under W1 at the same nitrogen level. Yield with the N1 treatment was higher than that with the N0 treatment, but not significantly different from that obtained with the N2 and N3 treatments. The W2 N1 treatment resulted in the highest water use and fertilizer agronomic efficiencies. Compared with local traditional practice(W3 N3), the net income and output-input ratio of W2 N1 were greater by 12.3 and 19.5%, respectively. These findings suggest that two irrigation events of 60 mm each coupled with application of 100 kg N ha-(–1) is sufficient to provide a high wheat yield during drought growing seasons in the NCP.
基金Supported by Special Fund for China Agricultural Industry Research System(CARS-20-2-2)Special Fund for Agricultural Industry Research System of Yunnan Province(YNGZTX-4-92)
文摘[Objective]The paper was to screen a new ideal sustained-release,long-lasting and low-toxic pesticide and convenient and efficient pesticide application technology for controlling Ceratovacuna lanigera and Baliathrips serratus. [Method]2% Imidacloprid GR were selected and applied in the soil for field efficacy trial. [Result] The optimum dosage of 2% imidacloprid GR was 30 kg/hm^2( active ingredient 600 g),which can be mixed with fertilizer( 30 kg pesticide and 40-80 kg fertilizer per hm^2) once combined with sugarcane planting management or big ridging during February and June. The control effects against C. lanigera and B. serratus could be more than 98. 2% and 81. 1%,respectively. The actual yield and sugar content in various pesticide treatments were increased by 33 390 kg/hm^2 and 6. 6% respectively compared to blank control. [Conclusion]2% imidacloprid GR has good control effects on C. lanigera and B. serratus. It is a new pesticide with ideal sustained-release,long-lasting and low-toxin effects against C. lanigera and B. serratus. Therefore,it could be used alternatively with other pesticides,to delay production and development of drug resistance.
基金Supported by the National Natural Science Foundation of China under Grant No 11774374the Natural Science Foundation of Shandong Province of China under Grant No ZR2016AL10
文摘We present an efficient three-dimensional coupled-mode model based on the Fourier synthesis technique. In principle, this model is a one-way model, and hence provides satisfactory accuracy for problems where the forward scattering dominates. At the same time, this model provides an efficiency gain of an order of magnitude or more over two-way coupled-mode models. This model can be applied to three-dimensional range-dependent problems with a slowly varying bathymetry or internal waves. A numerical example of the latter is demonstrated in this work. Comparisons of both accuracy and efficiency between the present model and a benchmark model are also provided.
基金Supported by Special Fund for China Agricultural Industry Research System(CARS-20-2-2)Special Fund for Agricultural Industry Research System of Yunnan Province(YNGZTX-4-92)
文摘[Objective] The paper was to provide scientific basis for popularization and application of 70% Thiamethoxam ZF. [Method] 70% Thiamethoxam ZF was selected and applied in the soil for controlling Ceratovacuna lanigera Zehntner and Baliathrips serratus Kobus. [ Result ] 70% Thiamethoxam ZF had good con-rol effect against C. lanigera and B. serratus. The optimum dosage of 70% Thiamethoxam ZF was 450 g/hm^2 (effective ingredients 315 g). 70% Thiamethoxam ZF ( dosage per hm^2 ) mixed with the regular fertilizer ( dosage per hm^2 ) should be applied together in sugarcane planting and management from February to June. The control effects against C. lanigera and B. serratus were above 98.4% and 82.9% respectively. The actual yield and sugar content were increased by more than 34 290 kg/hm^2 and 6.8% respectively compared to blank control. [ Conclusion] 70% Thiamethoxam ZF was a new ideal pesticide with characteristics of sustained- release, long-lasting and low-toxic for controlling C. lanigera and B. serratus, and should be applied widely in the sugarcane planting area.
基金supported by grants from the National High Technology Research and Development Program of China(863 Program)(No.2012AA020304)the National Natural Science Foundation of China(Grant No.31300643)the Innovation Fund for Postgraduate Students from the Simcere Pharmaceutical Company(No.02704051)
文摘The number of therapeutic monoclonal antibodies used in clinical trials has recently increased dramatically, leading to the development of optimized downstream purification processes[1]. Staphylococcal protein A (SPA), a cell-wall protein of Staphylococcus aureus, has been developed as a universal ligand for immunoglobulin G (IgG) purification because it binds specifically to the Fc portion of the IgG molecule of many mammals[2]. However, certain characteristics of SPA severely restrict the advancement of the antibody industry.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFB100140)National Natural Science Foundation of China(Grant No.51975136)+4 种基金Natural Science Foundation of Guangdong Province(Grant No.2023A1515011723)Industry-University-research Collaborative Innovation Base of Ministry of Education(Grant No.230703950183536,220903950010408)Special Research Projects in the Key Fields of Guangdong Higher Educational Universities(Grant No.2023ZDZX3016,2019KZDZX1009)Tertiary Education Scientific research project of Guangzhou Municipal Education Bureau(Grant No.202235139)Guangzhou University Research Project(Grant No.YJ2023034,YJ2021002).
文摘Considering the high-quality requirements related to agricultural crop production,the collaborative operation and application influence of sprinkler drip irrigation is an important issue in precision agriculture.The objective of this review is to give a comprehensive demonstration focusing on the subject of collaborative operation and application influence of sprinkler drip irrigation,by using a set of comparative analysis and literature bibliometric maps,therefore the sprinkler drip irrigation quality considering actual influential factors could be determined and analyzed.This review establishes on a broad spectrum of agricultural drip irrigation performance,throughout its whole procedure of collaborative monitoring,irrigation scheduling,application efficiency,and environmental influence,covering such aspects as soil physicochemical quality,irrigation scheduling,water resource redistribution,crop productivity,tillage management,climate adaptation,and environmental monitoring,etc.This review indicates that,the irrigation efficiency and drip infiltration quality of soil field can be planned precisely and allocated reasonably by sprinkler drip irrigation,which has extraordinary infiltration capability and enables much better performance,than that of other ordinary irrigation approaches in accuracy,stability,regularity,and efficiency.Thereafter,the investigation on the collaborative operation and application influence of sprinkler drip irrigation can be used to ensure the infiltration uniformity of moisture distribution,and then the high-quality requirements of practical irrigation performance can be met,too.This systematic review facilitates the productive soil-moisture-environment management for precision irrigation and agricultural production.
基金This study was financially supported by the National Key Research and Development Program(No.2016YFD0200700).
文摘Improving pesticide application efficiency is increasingly important in orchard spraying.In this study,a laser-scanning system was designed to acquire gridding volumes of a tree to quantify the geometry characteristics of the tree canopy in real-time.A laser-scanning sensor mounted on a linear guide was utilized to measure the structure of a target tree canopy.A computer was used to receive measurement data from the laser scanner and obtain the movement distance of the laser-scanning sensor from a controller.An algorithm written with VC#program was designed to calculate gridding volumes of trees by recognizing valid measurement data from the laser scanner.Laboratory evaluations were conducted on three kinds of regular objects,and the maximum relative errors of section volumes of the cuboid,triangular prism and cylinder objects were 3.3%,7.9%and 9.4%,respectively,which illustrated that the algorithm could calculate the section volumes in different parts of the objects with high accuracy.A conifer tree and an apple tree were chosen to verify detecting accuracy of the laser-scanning system at variable speeds and grid sizes.The variation coefficients of total volumes for each kind of the tree were 0.078 and 0.041,respectively,which indicated that the laser-scanning system could be applied to provide the gridding volumes of different canopy densities in real-time with good reliability for guiding a variable-rate sprayer.
基金This study was financially supported by the National KeyResearch and Development Program(2016YFD0200700).
文摘To improve the precision spraying strategy and reduce excessive pesticide application in orchards,an air-assisted sprayer integrated with a laser-scanning system was developed to realize the toward-target variable-rate spraying.In the spray control system,a method of calculating canopy gridding volumes was designed to ensure that the canopy was divided into a uniform grid size,a variable-rate spray model was used in the flow rate decision software to control the spray output according to the canopy gridding volumes and travel speed,and a method of saving and accessing spray data was used to control the spray delay.The effects of different grid sizes and travel speeds on the spray performance were evaluated by quantifying spray coverage uniformity inside tree canopies.The results showed that spray coverage uniformity declined with increasing grid width from 0.14 to 0.28 m although the mean spray coverage on each target location showed no significant differences.Additionally,there were no significant variations in mean spray coverage at speeds of 1.0,1.2 and 1.4 m/s for a tested tree of 1.6 m width and at any experimental speeds for a tested tree of 1.3 m width,which indicated that the variable-rate sprayer could provide good spray coverage uniformity under various travel speeds with a canopy size limitation.Compared with the same sprayer without the variable-rate spray function,the intelligent sprayer prototype realized effective toward-target spraying and avoided overspraying while providing sufficient spray coverage.
基金Project supported by the National Natural Science Foundation of China(Nos.61131001,61404077,61571248)the Science and Technology Fund of Zhejiang Province(No.2015C31090)+2 种基金the Natural Science Foundation of Ningbo(No.2014A610147)State Key Laboratory of ASIC&System(No.2015KF006)the K.C.Wong Magna Fund in Ningbo University
文摘Carbon nanotube field effect transistor(CNFET) shows lower threshold voltage and smaller leakage current in comparison to its CMOS counterpart. In this paper, two kinds of CNFET-based rectifiers, full-wave rectifiers and voltage doubler rectifiers are presented for biomedical implantable applications. Based on the standard 32 nm CNFET model, the electrical performance of CNFET rectifiers is analyzed and compared. Simulation results show the voltage conversion efficiency(VCE) and power conversion efficiency(PCE) achieve 70.82% and 72.49% for CNFET full-wave rectifiers and 56.60% and 61.17% for CNFET voltage double rectifiers at typical 1.0 V input voltage excitation, which are higher than that of CMOS design. Moreover, considering the controllable property of CNFET threshold voltage, the effect of various design parameters on the electrical performance is investigated.It is observed that the VCE and PCE of CNFET rectifier increase with increasing CNT diameter and number of tubes. The proposed results would provide some guidelines for design and optimization of CNFET-based rectifier circuits.