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郑有飞, Longhui Li a, b, Qiang Yu a, *, Youfei Zheng c, Jing Wang a, Quanxiao Fang a
Field Crops Research 96(2006)133-141,-0001,():
-1年11月30日
Currently available models of photosynthate partitioning in crops are poorly developed compared to carbon and water balance models. This paper presents a dynamic photosynthate partitioning model (PPModel) that simulates the partitioning of crop biomass to leaf, stem and root through the interaction between carbon gain (assimilation less respiration) and transpiration, in relation to environmental factors. The central concept is the theory of plant functional equilibrium, in which transpirational loss and water uptake are balanced, within acceptable limits, by a dynamic partitioning of assimilates between shoot and root growth. The model was shown to perform effectively against experimental data for growth and partitioning of biomass in winter wheat (collected over a 2-year period), when environmental factors varied daily and water supply was controlled over a wide range.
Photosynthate partitioning, Transpiration, Water absorption, Winter wheat, Mathematic model
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郑有飞, Wei Gao *, Youfei Zheng , James R. Slusser , Gordon M. Heisler , Richard H. Grant , Jianqiang Xu and Douliang He
Photochemistry and Photobiology 80(2004)127-131,-0001,():
-1年11月30日
Stratospheric ozone depletion has caused an increase in the amount of ultraviolet-B (UV-B) radiation reaching the earth's surface. Numerous investigations have demonstrated that the effect of UV-B enhancements on plants includes reduction in grain yield, alteration in species competition, susceptibility to disease and changes in plant structure and pigmentation. Many experiments examining UV-B radiation effects on plants have been conducted in growth chambers or greenhouses. It has been questioned whether the effect of UV-B radiation on plants can be extrapolated to field responses from indoor studies because of the unnaturally high ratios of UV-Bultraviolet-A radiation (320-400nm) and UV-Bphotosynthetically active radiation (PAR) in many indoor studies. Field studies on UV-B radiation effect on plants have been recommended to use the UV and PAR irradiance provided by natural light. This study reports the growth and yield responses of a maize crop exposed to enhanced UV-B radiation and the UV-B effects on maize seed qualities under field conditions. Enhanced UV-B radiation caused a significant reduction in the dry matter accumulation and the maize yield in turn was affected. With increased UV-B radiation the flavonoid accumulation in maize leaves increased and the contents of chlorophyll a, b and (a+b) of maize leaves were reduced. The levels of protein, sugar and starch of maize seed decreased with enhanced UV-B radiation, whereas the level of lysine increased with enhanced UV-B radiation.
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郑有飞, 马玉霞, 文秀萍, 桑建人
南京气象学院学报:2003,26(2):252~257,-0001,():
-1年11月30日
通过统计分析,选取影响银川地区高血压病发病率的主要气象因素,将其作为输入变量经多层前馈型神经网络的BP(Back Propagation)算法进行学习训练,建立了疾病发病率的人工神经网络(ANN,Artifical Neural Net)预报模型。结果表明:该方法计算简便、误差较小,为疾病发病率预报提供了一种新的预报方法。
高血压病发病率, 人工神经网络, BP网络, 预报模型
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郑有飞, 张荣刚, 何雨红, 肖薇
南京气象学院学报:2003,26(2):258~262,-0001,():
-1年11月30日
观测分析了大田条件下UV-B 辐射增强对麦田中麦蚜的影响,结果表明UV-B 辐射增强,蚜虫发生总量、小麦植株发生的百分率显著降低,蚜虫在穗部和植株上部叶片的发生概率下降,但蚜虫在叶片背光面发生数量增多,小麦植株的虫害发生概率降低。
UV-B 辐射, 麦蚜, 小麦
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【期刊论文】Environmental impacts and benefits ofregional power grid interconnections for China
郑有飞, Fahua Zhu a, Youfei Zheng b, Xulin Guo c, *, Sheng Wang b
Energy Policy 33(2005)1797-1805,-0001,():
-1年11月30日
This paper describes the development ofChina's power industry, present situation, environmental influences and potential benefits of regional power grid interconnections in China. Power plants in China are mainly thermal, burning fossil fuels especially coal which emit a great deal ofpollutants and greenhouse gases such as SO2, NOx and CO2. China leads all other countries in emissions of SO2, CO2, and the power industry is the largest contributor to these emissions. There are a number ofenvironmental benefits through regional power grid interconnection. That is, the construction ofsmall electricity generation capacity would be avoided; natural resources would be used to generate electricity on a regional scale; and generating sources can be separated from centers ofelectricity use, which will decrease emission of pollutants and greenhouse gases and help to reduce human exposure to elevated air pollutant concentrations. Therefore, gradually enlarged power grids, and power grid interconnection, should be part of the general pattern ofpower system development in China.
Power, Environment, China
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