Linear Disposal of Wheatstone Bridge in Strain Measurement     

WEN Cheng  QIN Shu-ren 《保鲜与加工》2004,(1):28-31

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Soft-switching Analysis Phase-Shifted-FB-ZVS-PWM DC-DC Converter With Saturable Inductor     

DU Jun~  ZHOU Luo-wei~  LU Zhi-guo~ 《保鲜与加工》2004,(1):53-57

Compared with the traditional full-bridge(FB)zero-voltage-switched(ZVS) pulsewidth-modulated(PWM) converter, the FB-ZVS-PWM converter with a saturable inductor has a wider load range with ZVS and smaller circulating energy as well as smaller duty cycle loss. By analyzing the operation principle of the converter, this paper studies design considerations of the parameter bringing about ZVS and dead time of the switch, and gives out the design method, finally simulation testing has been carried out.  相似文献   

The Biological Effects of Low Frequency Electromagnetic Fields on Cells     

LIU Xin~  ZHU Jian~  ZHONG Ji-kang~ 《保鲜与加工》2004,(1):112-115

The biological effects of ELFMES including proliferation and apoptosis of cells as well as the damage of DNA are initially evaluated with the treatment of plant cells and human pulmonary fibroblasts in low frequency magnetic fields with certain intensity and different time intervals in vitro. Cell culture, counting in vitro, fluorescent dyeing analysis and single cell gel electrophoresis are adopted. The results demonstrate that the electromagnetic field with the intensity of 3mT can affect the proliferation and apoptosis of cells significantly.  相似文献   

Analysis of Cleanroom Technology Through Angle of Design     

YANG Tao~  WANG Zheng~  TAN Xin~  LI Bin~ 《保鲜与加工》2004,(1):88-91

During the implementation of Cleanroom Model, there are a lot of particular problems need to be resolved, which make it indispensable to grasp the essence and the principles of CRM. The article is on the essential research work in the design procedure of the Cleanroom technology. Through the analysis, it proposes a general architecture, based on which the entry point of the solving process and the distribution of the reducing procedure are introduced.  相似文献   

Nash Equilibrium Mechanic of Environmental and Human Capital     

LI Jia-ming  JING Xi-ling 《保鲜与加工》2004,(1):135-138

The externality of surrounding is introduced into the 2-capital of economical increasing models, which includes human factors, to explore the influences of circumstances contradiction on the human capital formation. The normal and special nash equilibrium of environmental and human capital is presented through a limited boundary model of overlapping generations. The character of equilibrium trail and its economical meaning are examined. The study on the model shows that laissez faire economy will be either stagnant,growing,or collapsing in the long-run,depending on the returns of the learning technology with respect to the two kinds of capital,the initial state of economy,and the relative price of the environmental and consumption goods.  相似文献   

Customer Service Satisfaction Evaluation System and Method Viewed From Supply Chain Management     

LIU Jing-nan  MENG Wei-dong  WU Jun 《保鲜与加工》2004,(1):146-151

Based on experience in customer service evaluation,through the analysis of many factors affecting customer satisfaction calculation estimate, customer service evaluation rules as well as customer-oriented and supply chain partner-oriented methods are developed and discussed from the view of supply chain, besides, we construct two sets of customer satisfaction evaluation systems, in which we perform non-dimensional analysis on evaluation system to form single factor evaluation matrix after using improved AHP to determine each factor item's weighting ,utilizing fuzzy decision theory to construct evaluation model for integrated estimate. This evaluation method is scientific, round and objective with more stability and convienience in practical use.  相似文献   

桃铁离子吸收动力学研究   总被引：3，自引：0，他引：3  

方从兵  孙俊 《中国农学通报》2001,17(1):4-6

以毛桃幼苗为试材，对不同铁形态、pH值和盐胁迫条件下铁离子吸收动力学特性进行了研究。结果表明，pH是影响铁吸收的主要因素，不同铁形态的有效性随pH的变化而变化；pH和铁形态影响桃铁离子吸收动力学参数Km和Imax；NaCI胁迫对盐敏感性植物（桃）铁吸收特性的影响，可能与质膜透性、载体系统活性以及介质中有效铁含量有关。  相似文献   

美国杏李不同栽培模式适应性评价   总被引：1，自引：0，他引：1  

斯琴格日乐  德永军  王兵  白秀兰  吴慧  张彦廷  高秀丽 《干旱区资源与环境》2007,21(11):141-145

本文通过对不同品种不同栽培模式美国杏李生长和林地土壤含水量动态变化分析表明:栽培模式3抗旱性好,在研究地可广泛应用;栽培模式2在研究地比较适合在有一定灌溉条件的地区应用;栽培模式1抗旱性适中,可在研究地土壤水分条件尚好的地区应用;栽培模式5可在研究地土壤水分条件尚好的地区控制应用;栽培模式4在研究地不宜采用。  相似文献   

水资源联合调度模型在额济纳绿洲生态环境建设中的应用   总被引：1，自引：0，他引：1  

邰生霞  陈彬  何桥  毕佳 《干旱区资源与环境》2007,21(4):76-79

对日趋缺水的额济纳绿洲,进行河水与地下水进行联合运用的目的是:减少水资源浪费,恢复生态水位,保护绿洲。按照国家水利部(1997)496号文件:《现状工程条件下黑河干流水量分配方案》(简称“97甘蒙分水方案),不同保证率下分配给内蒙古的水量。根据狼心山水文断面入境水量丰枯变化的分析结果,建立水资源联合调度模型,对四种不同来水方案进行计算。结果表明,执行“甘蒙分水”,采用内蒙长衬砌渠道输水,当保证率P=50%时,入境狼心山水量为7.527×108m3,到2020年地下水位埋深回升到2.35m,相应绿洲面积将扩大到5005.01km2,绿洲植被总盖度可达到58%。基本满足天然非灌溉林草的需水,逐步回补到生态要求的限定水位,使绿洲逐步得到恢复。  相似文献   

Rice-residue biochar influences phosphorus availability in soil with contrasting P status     

Subham Mukherjee  Jagdeep Singh  Bhupinder Pal Singh 《Archives of Agronomy and Soil Science》2020,66(6):778-791

ABSTRACT

Thermo-chemical conversion of crop residues to produce biochar is an emerging strategy in the context of sustainable phosphorous (P) use and residue management. An incubation study for 90 d was conducted to investigate the effects of rice-residue biochar (0, 10, 20 and 40 g kg^?1) in combination with inorganic-P (KH₂PO₄) (0, 25 and 50 mg kg^?1) on phosphorous availability in medium- and high-P status soils. Increasing biochar addition rates alone or in combination with inorganic-P resulted in a significant increase in P pools, i.e. plant available P or Olsen-P (from 8 to 132 mg kg^?1 in medium-P and 15 to 160 mg kg^?1 in high-P soils), microbial biomass P and various mineral-bound inorganic-P fractions in the order (Ca-P > organic-P > Al-P > loosely held/soluble-P > Fe-P > reductant soluble-P). Further, lower phosphatase activity (19–50%) with increasing rates of biochar addition in both soils elucidates the ability of biochar to act as a long-term source of available P in the experimental soils. The results demonstrate that rice-residue biochar can directly or indirectly enhance the status of available P in soils and hence can be used as a beneficial amendment to meet the crop P demand.  相似文献