A field experiment was conducted for two consecutive years in a farmer's field at Haji Mora Village, Dera Ismail Khan (D.I. Khan) in the Northwest Frontier Province (NWPP) of Pakistan to compare various management...A field experiment was conducted for two consecutive years in a farmer's field at Haji Mora Village, Dera Ismail Khan (D.I. Khan) in the Northwest Frontier Province (NWPP) of Pakistan to compare various management practices, such as the effect of various organic manures and gypsum in a rice-wheat cropping system on a saline-sodic Entisol (Zindani soil series). The treatments consisted of 1) a control (rice-wheat), 2) gypsum, 3) farmyard manure (FYM), 4) berseem (Trifolium alexzndrinum L.) as green manure (GM), and 5) dhancha (Sesbania sp.) as GM. All treatments increased yields of both rice and wheat significantly (P < 0.01) over the control, with the green manure treatments proving more economical than the others; while they decreased pH, electrical conductivity (EC), and sodium adsorption ratio (SAR) of the soil. Saturation percentage and available water of the soil were raised for all treatments due to an increase in organic matter content of the soil.展开更多
The effects of three nitrogen sources （ammonium, nitrate and ammonium＋nitrate） and three salt treatments （0, 100 and 200 mM NaCl） on nitrate reductase activity, proline, soluble protein and carbohydrate contents ...The effects of three nitrogen sources （ammonium, nitrate and ammonium＋nitrate） and three salt treatments （0, 100 and 200 mM NaCl） on nitrate reductase activity, proline, soluble protein and carbohydrate contents in psylliom （Plantago ovata） plants were Studied. The nitrate reductase activity tended to increase when NO3- was included in the root-zone solution, but decrease as salinity increased. All N sources stimulated plant growth and nutrient uptake. Shoot and root dry matter tended to decrease as salinity increased, but less so when both NH4＋ and NO3- were present. Shoot biomass accumulated to significantly greater quantities under the mixed-N treatments than when produced using either NH4＋ or NO3- N-form alone. Although not statistically significant, the root biomasses showed a similar tendency. Generally, leaf proline and soluble shoot carbohydrate contents increased with increasing salinity in contrast to soluble protein which decreased regardless of the N source. Under salinity conditions, the concentration of Na＋ in shoot and root tissues was highest in ammonium-N treatment, while that of K＋ was highest in the mixed-N treatment.展开更多
Forecasters predict that by 2020 there will be 4.5 or 5 million tons per annum maize supply deficiency in Vietnam. As a result of this projection, the government responded by shifting 80,000 ha of low-efficiency rice ...Forecasters predict that by 2020 there will be 4.5 or 5 million tons per annum maize supply deficiency in Vietnam. As a result of this projection, the government responded by shifting 80,000 ha of low-efficiency rice production areas into maize production （2014-2015） and this area of production for maize is expected to increase to 150,000 ha by 2016-2020. Nevertheless, not all commercial maize hybrids could be suitable for rice-growing land in the Mekong Delta and a national project of hybrid maize development for Mekong Delta has been conducted since early 2014. In the project, yield trials of 20 maize hybrids, sourced from Vietnamese institutions and the private sector including Syngenta （NK67） and Dekalb （DK9901）, were sown in Dong Thap, Hau Giang and Long An provinces situated in the Mekong Delta, in minor acid sulphate soils with a pH of 5.0-5.5. The trial included three replications in an Alpha lattice design conducted during spring-summer in 2014. The hybrids flowered at 50-52 d after planting and physiologically matured between 93-97 d after planting. This suggested they would be suitable for cropping systems, which was comprised of three seasons per year. To determine which hybrid is best suited for the region, researchers evaluated yield and ear characteristics. The average yield of the genotypes across locations was 52.03, 54.92 and 57.60 quintals/ha, respectively, and the heritability of genotypes in each location was 0.51, 0.81 and 0.61, respectively. The mean yield of DK9901 was 58.19 quintals/ha, ranking the 7th among 20 hybrids, and NK67 was 47.58 quintals/ha, ranking the 19th. The grand mean was 54.92 quintals/ha and heritability for all genotypes was 0.79. The highest yield was produced by the Southern seed company hybrid SSC474 （69.39 quintals/ha）, which yielded significantly more maize than DK9901 （58.19 quintals/ha） at P 〈 0.05, followed by VS71 from National Maize Research Institute （NMRI） at 63.52 quintals/ha, and LCH9A from NMRI at 63.39 quintals/ha. Although the yield of the VS71 hybrid was greater than the DK9901 hybrid, the ear characteristics were less desirable. Therefore, after comparing these hybrids, it was concluded that SSC474 and LCH9A were the two most suitable hybrids to produce in the Mekong Delta.展开更多
In this paper,an efficient model structure composed of a second-order resistance-capacitance network and a simply analytical open circuit voltage versus state of charge(SOC) map is applied to characterize the voltage ...In this paper,an efficient model structure composed of a second-order resistance-capacitance network and a simply analytical open circuit voltage versus state of charge(SOC) map is applied to characterize the voltage behavior of a lithium iron phosphate battery for electric vehicles(EVs).As a result,the overpotentials of the battery can be depicted using a second-order circuit network and the model parameterization can be realized under any battery loading profile,without a special characterization experiment.In order to ensure good robustness,extended Kalman filtering is adopted to recursively implement the calibration process.The linearization involved in the calibration algorithm is realized through recurrent derivatives in a recursive form.Validation results show that the recursively calibrated battery model can accurately delineate the battery voltage behavior under two different transient power operating conditions.A comparison with a first-order model indicates that the recursively calibrated second-order model has a comparable accuracy in a major part of the battery SOC range and a better performance when the SOC is relatively low.展开更多
文摘A field experiment was conducted for two consecutive years in a farmer's field at Haji Mora Village, Dera Ismail Khan (D.I. Khan) in the Northwest Frontier Province (NWPP) of Pakistan to compare various management practices, such as the effect of various organic manures and gypsum in a rice-wheat cropping system on a saline-sodic Entisol (Zindani soil series). The treatments consisted of 1) a control (rice-wheat), 2) gypsum, 3) farmyard manure (FYM), 4) berseem (Trifolium alexzndrinum L.) as green manure (GM), and 5) dhancha (Sesbania sp.) as GM. All treatments increased yields of both rice and wheat significantly (P < 0.01) over the control, with the green manure treatments proving more economical than the others; while they decreased pH, electrical conductivity (EC), and sodium adsorption ratio (SAR) of the soil. Saturation percentage and available water of the soil were raised for all treatments due to an increase in organic matter content of the soil.
文摘The effects of three nitrogen sources （ammonium, nitrate and ammonium＋nitrate） and three salt treatments （0, 100 and 200 mM NaCl） on nitrate reductase activity, proline, soluble protein and carbohydrate contents in psylliom （Plantago ovata） plants were Studied. The nitrate reductase activity tended to increase when NO3- was included in the root-zone solution, but decrease as salinity increased. All N sources stimulated plant growth and nutrient uptake. Shoot and root dry matter tended to decrease as salinity increased, but less so when both NH4＋ and NO3- were present. Shoot biomass accumulated to significantly greater quantities under the mixed-N treatments than when produced using either NH4＋ or NO3- N-form alone. Although not statistically significant, the root biomasses showed a similar tendency. Generally, leaf proline and soluble shoot carbohydrate contents increased with increasing salinity in contrast to soluble protein which decreased regardless of the N source. Under salinity conditions, the concentration of Na＋ in shoot and root tissues was highest in ammonium-N treatment, while that of K＋ was highest in the mixed-N treatment.
文摘Forecasters predict that by 2020 there will be 4.5 or 5 million tons per annum maize supply deficiency in Vietnam. As a result of this projection, the government responded by shifting 80,000 ha of low-efficiency rice production areas into maize production （2014-2015） and this area of production for maize is expected to increase to 150,000 ha by 2016-2020. Nevertheless, not all commercial maize hybrids could be suitable for rice-growing land in the Mekong Delta and a national project of hybrid maize development for Mekong Delta has been conducted since early 2014. In the project, yield trials of 20 maize hybrids, sourced from Vietnamese institutions and the private sector including Syngenta （NK67） and Dekalb （DK9901）, were sown in Dong Thap, Hau Giang and Long An provinces situated in the Mekong Delta, in minor acid sulphate soils with a pH of 5.0-5.5. The trial included three replications in an Alpha lattice design conducted during spring-summer in 2014. The hybrids flowered at 50-52 d after planting and physiologically matured between 93-97 d after planting. This suggested they would be suitable for cropping systems, which was comprised of three seasons per year. To determine which hybrid is best suited for the region, researchers evaluated yield and ear characteristics. The average yield of the genotypes across locations was 52.03, 54.92 and 57.60 quintals/ha, respectively, and the heritability of genotypes in each location was 0.51, 0.81 and 0.61, respectively. The mean yield of DK9901 was 58.19 quintals/ha, ranking the 7th among 20 hybrids, and NK67 was 47.58 quintals/ha, ranking the 19th. The grand mean was 54.92 quintals/ha and heritability for all genotypes was 0.79. The highest yield was produced by the Southern seed company hybrid SSC474 （69.39 quintals/ha）, which yielded significantly more maize than DK9901 （58.19 quintals/ha） at P 〈 0.05, followed by VS71 from National Maize Research Institute （NMRI） at 63.52 quintals/ha, and LCH9A from NMRI at 63.39 quintals/ha. Although the yield of the VS71 hybrid was greater than the DK9901 hybrid, the ear characteristics were less desirable. Therefore, after comparing these hybrids, it was concluded that SSC474 and LCH9A were the two most suitable hybrids to produce in the Mekong Delta.
基金Project (No. 61004092) supported by the National Natural ScienceFoundation of China
文摘In this paper,an efficient model structure composed of a second-order resistance-capacitance network and a simply analytical open circuit voltage versus state of charge(SOC) map is applied to characterize the voltage behavior of a lithium iron phosphate battery for electric vehicles(EVs).As a result,the overpotentials of the battery can be depicted using a second-order circuit network and the model parameterization can be realized under any battery loading profile,without a special characterization experiment.In order to ensure good robustness,extended Kalman filtering is adopted to recursively implement the calibration process.The linearization involved in the calibration algorithm is realized through recurrent derivatives in a recursive form.Validation results show that the recursively calibrated battery model can accurately delineate the battery voltage behavior under two different transient power operating conditions.A comparison with a first-order model indicates that the recursively calibrated second-order model has a comparable accuracy in a major part of the battery SOC range and a better performance when the SOC is relatively low.
