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Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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science china(Technological sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2, HUANG GuanHua1,2 & QU ZhongYi3 1 Center for agriculture Water Research, china Agricultural university, Beijing 100083, china 2 Chinese-Israeli International Center for Research and Training in agriculture, china Agricultural university, Beijing 100083, china 3 Water Conservancy and Civil Engineering college, Inner Mongolia Agricultural university, Hohhot 010018, china 1. Center for agriculture Water Research China Agricultural University Beijing 100083 China 2. Chinese-Israeli International Center for Research and Training in agriculture China Agricultural University Beijing 100083 China 3. Water Conservancy and Civil Engineering college Inner Mongolia Agricultural University Hohhot 010018 China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

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Analysis of synonymous codon usage and evolution of begomoviruses

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Journal of Zhejiang university-science B(Biomedicine & Biotechnology) 2008年第9期9卷 667-674页

作者： Xiao-zhong XU1, Qing-po LIU2, Long-jiang FAN1, Xiao-feng CUI1, Xue-ping ZHOU1 (1college of agriculture and Biotechnology, Zhejiang university, Hangzhou 310029, china) (2School of agriculture and Food science, Zhejiang Forestry university, Lin’an 311300, china) college of agriculture and Biotechnology Zhejiang University Hangzhou 310029 China.

Begomoviruses are single-stranded DNA viruses and cause severe diseases in major crop plants worldwide. Based on current genome sequence analyses, we found that synonymous codon usage variations in the protein-coding genes of begomoviruses are mainly influenced by mutation bias. Base composition analysis suggested that the codon usage bias of AV1 and BV1 genes is significant and their expressions are high. Fourteen codons were determined as translational optimal ones according to the comparison of codon usage patterns between highly and lowly expressed genes. Interestingly the codon usages between begomoviruses from the Old and the New Worlds are apparently different, which supports the idea that the bipartite begomoviruses of the New World might originate from bipartite ones of the Old World, whereas the latter evolve from the Old World monopartite begomoviruses.

关键词： Begomovirus Synonymous codon usage Evolution Bioinformatics

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Phylogenetic analysis of aerobic anoxygenic phototrophic bacteria and their relatives based on farnesyl pyrophosphate synthase gene

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Acta Oceanologica Sinica 2010年第5期29卷 82-89页

作者： FENG Fuying JIAO Nianzhi DU Hailian ZENG Yonghui State Key Laboratory of Marine Environmental science Xiamen University Xiamen 361005 China college of life sciences Innermongolia Agriculture University Huhhot 010018 China

The study aims to reveal phylogenetic and evolutionary relationship between aerobic anoxygenic phototrophic bacteria（AAnPB） and their relatives,anaerobic anoxygenic phototrophic bacteria（AnAnPB） and nonphototrophic bacteria（NPB,which had high homology of 16S rDNA gene with AAnPB and fell into the same genus）,and validate reliability and usefulness of farnesyl pyrophosphate synthase（FPPS） gene for the phylogenetic *** genes with our modified primers and 16S rDNA genes with general primers,were amplified and sequenced or retrieved from GenBank *** contrast to 16S rDNA gene phylogenetic tree,AAnPB were grouped into two clusters and one branch alone with no intermingling with NPB and AnAnPB in the tree constructed on *** branch of AAnPB,in both trees,was located closer to outgroup species than AnAnPB,which implicated that some AAnPB would be diverged earlier in FPPS evolutionary history than AnAnPB and *** AAnPB and NPB were closer located in both trees and this suggested that they were the closer relatives than *** codon usage in FPPS with phylogenetic analysis,the results indicates that FPPS gene and 16S rRNA gene have similar evolutionary pattern but the former seems to be more reliable and useful in determining the phylogenic and evolutionary relationship between AAnPB and their *** is the first attempt to use a molecular marker beside 16S rRNA gene for studying the phylogeny of AAnPB,and the study may also be helpful in understanding the evolutionary relationship among phototrophic microbes and the trends of photosynthetic genes transfer.

关键词： aerobic anoxygenic phototrophic bacteria farnesyl pyrophosphate synthase phylogeny anaerobic anoxygenic phototrophic bacteria nonphototrophic bacteria

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THE VOID FRACTION DISTRIBUTION IN TWO-DIMENSIONAL GAS-LIQUID TWO PHASE FLOW USING IMAGE PROCESS METHOD

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Journal of Hydrodynamics 2006年第2期18卷 127-134页

作者： ZHAO Ke-yu CHENG Wen LIAO Wei-li ZHOU Xiao-de college of Water Resource and Architectural Engineering Northwest Agriculture and Forestry University Xi＇an 712100 China Environment Research Institute Xi＇ an University of Technology Xi＇an 710048 China

An image processing method for measuring the instantaneous two-dimensional （2D） local void fraction at high bubble number density was proposed. It was based on computing a correlation between the locally averaged brightness of the bubble plume images and the real void fraction. The method was tested using the 2D distribution of local void fraction from visualized image, where a correlation between the locally averaged brightness and the projection void fraction was derived by introducing an ideal of overlapping probability of the bubble-images under various conditions. This research was used to study the behavior of the bubbly flows with aspect ratio of 1.0,1.5, and 2.0. The present method was applied to the instantaneous measurement. The void fraction for bubble plumes of three different aspect ratios with three different bubble generating flow rates were measured for the clarification of the effect of the bubble on the behavior of the bubbly flows. Dependency of the void fraction on the gas flow rate was measured and compared to other results from the literature. In the range of our experiments, it was observed that not only does an aspect ratio of the tank affect the structure of the plume, but also the gas flow rate in the tank affects the structure of the plume.

关键词： local void fraction gas-liquid two-phase flow,brightness aspect ratio the projection void fraction

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VC及柠檬酸对南五味子提取物抑制鸡蛋腐败菌的增效作用

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中国食品学报 2012年第9期12卷 152-157页

作者：赵美美于新仲恺农业工程学院轻工食品学院广州510225

以腐败鸡蛋分离的4种腐败细菌为目标菌,研究南五味子提取物中添加VC、柠檬酸对抑制鸡蛋腐败菌的增效作用。体外抑菌单因素试验证实,在南五味子70%乙醇提取物中单独添加VC、柠檬酸可以增强对部分目标菌的抑制作用。采用Box-Behnken设计... 详细信息

以腐败鸡蛋分离的4种腐败细菌为目标菌,研究南五味子提取物中添加VC、柠檬酸对抑制鸡蛋腐败菌的增效作用。体外抑菌单因素试验证实,在南五味子70%乙醇提取物中单独添加VC、柠檬酸可以增强对部分目标菌的抑制作用。采用Box-Behnken设计及响应面分析法优化提取物配方。试验结果表明,生药量66.7g/L的南五味子提取物水溶液中加入4.0%VC、2.8%柠檬酸,抑菌效果佳,抑菌圈直径达到32.73mm。与空白对照相比,抑菌增效作用显著。

关键词：南五味子提取物响应面优化鸡蛋腐败菌抑菌作用

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Globally Exponential Stability of a Class of Impulsive Neural Networks with Variable Delays

Globally Exponential Stability of a Class of Impulsive Neura...

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2009中国控制与决策会议

作者： Jianfu Yang,Fengjian Yang,Chaolong Zhang,Dongqing Wu,Chuanxiang Gao Department of Computation science,zhongkai university of agriculture and Engineering guangzhou,510225,P.R china

The main purpose of this paper is to study the globally exponential stability of the equilibrium point for a class of impulsive neural networks with time-varying *** assuming global Lipschitz conditions on the activation functions,applying idea of vector Lyapunov function,combining Young inequality and Halanay differential inequality with delay,the sufficient conditions for globally exponential stability of neural networks are obtained.

关键词： Impulse Neural networks Time-varying delays Globally exponential stability Lyapunov function

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Comparsion of the Effects of Succinate and NADH on Postmortem Metmyoglobin Redcutase Activity and Beef Colour Stability

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Journal of Integrative agriculture 2014年第8期13卷 1817-1826页

作者： GAO Xiao-guang WANG Zhen-yu TANG Meng-tian MA Chang-wei DAI Rui-tong college of Food science and Nutritional Engineering China Agricultural University college of Biological science and Engineering Hebei University of Science and Technology Institute of Agro-Products Processing science and technology Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products ProcessingMinistry of Agriculture

In two experiments, the effects of succinate and NADH（reduced nicotinamide adenine dinucleotide） on metmyoglobin reductase activity and electron transport chain-linked metmyoglobin reduction were investigated and compared. In experiment 1, metmyoglobin（MetMb）, substrate and inhibitors were incubated with mitochondria. Comparsion of the effects of succinate and NADH on MetMb reduction was investigated. The MetMb percentage in sample treated with 8 mol L-1 succinate decreased by about 69% after 3 h incubation, and the effect was inhibited by the addition of 10 mol L-1 electron transfer chain complex II inhibitor malonic acid; the MetMb percentage in samples treated with 2 mol L-1 NADH decreased by 56% and the effect was inhibited by the addition of 0.02 mol L-1 electron transport chain complex I inhibitor rotenone. These results indicated that electron transport chain played an important role in MetMb reduction. Both complex II and complex I take part in the MetMb reduction in mitochondria through different pathways. NADH-MetMb reduction system was less stable than succinateMetMb system. In experiment 2, the beef longissimus dorsi muscle was blended with different concentrations of succinate or NADH. Enhancing patties with higher concentration of succinate or NADH improved colour stability in vacuum packaged samples（P〈0.05）. These results verified that mitochondria electron transport chain is related to the MetMb reduction in meat system.

关键词： succinate NADH malonic acid rotenone metmyoglobin electron transport chain

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Cadmium and Zinc Accumulation in Maize Grain as Affected by Cultivars and Chemical Fixation Amendments

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Pedosphere 2011年第5期21卷 650-656页

作者： GUO Xiao-Fang WEI Ze-Bin WU Qi-Tang QIU Jin-Rong ZHOU Jian-Li Key Laboratory of Ecological agriculture of Ministry of agriculture of china College of Natural Resources and Environ- ment South China Agricultural University Guangzhou 510642 (China) South china Institute of Environmental sciences Ministry of Environmental Protection Guangzhou 510655 (China) college of agriculture Yangtze University Jingzhou 434025(China)

A field experiment was conducted to investigate the effects of soil amendments(lime,nano-Si foliar solution and used diatomite) on the growth and metal uptake of three maize(Zea mays L.) cultivars grown in a Cd and Zn-contaminated acidic *** addition of lime significantly increased the maize grain yields and decreased the concentrations of Zn and Cd in the grains and shoots of maize when compared with the *** the three maize cultivars,Yunshi-5 accumulated the lowest amounts of Cd and Zn in the *** concentrations of Zn and Cd in the grain of Yunshi-5 conformed to the Chinese feed *** data revealed that a combination of low metal-accumulating maize and chemical fixation could effectively provide a barrier to prevent metals from entering the human food chain.

关键词： grain yield heavy metal low metal-accumulating cultivar Zea mays L.

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Identification of Prorocentrum minimum and Takayama pulchella by fluorescence in situ hybridization through epifluorescence microscopy and flow cytometry

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Acta Oceanologica Sinica 2009年第2期28卷 103-114页

作者： HOU Jianjun LAI Hongyan HUANG Bangqin CHEN Jixin college of Fisheries Huazhong Agricultural University Wuhan 430070 China college of life sciences Hubei Normal University Huangshi 435002 China State Key Laboratory of Marine Environmental science Environmental Science Research Center Xiamen University Xiamen 361005 China Key Laboratory of Freshwater Fish Germplasm Resources and Biotechnology Yangtse River Fisheries Research Institute Jinzhou 434000 China State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

Partial rDNA sequences of Prorocentrum minimum and Takayama pulchella were amplified, cloned and sequenced, and these sequence data were deposited in the GenBank. Eight oligonucleotide probes （DNA probes） were designed based on the sequence analysis. The probes were employed to detect and identify P. minimum and T. pulchella in unialgal and mixed algal samples with a fluorescence in situ hybridization method using flow cytometry. Epifluorescence micrographs showed that these specific probes labeled with fluorescein isothiocyanate entered the algal cells and bound to target sequences, and the fluorescence signal resulting from whole-cell hybridization varied from probe to probe. These DNA probes and the hybridization protocol we developed were specific and effective for P. minimum and T. pulchella, without any specific binding to other algal species. The hybridization efficiency of different probes specific to P. minimum was in the order： PM18S02 PM28S02 〉 PM28S01 〉PM18S01, and that of the probes specific to T. pulcheUa was TP18S02 TP28S01 〉 TP28S02 〉TP18S01. The different hybridization efficiency of the DNA probes could also be shown in the fluorescent signals between the labeled and unlabeled cells demonstrated using flow cytometry. The DNA probes PM18S02, PM28S02, TP18S02 and TP28S01, and the protocol, were also useful for the detection of Mgae in natural samples.

关键词： oligonucleotide DNA probes Prorocentrum minimum Takayama pulcheUa fluorescence in situ hybridization flow cytometry

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Response of Tomato Plants to a New Application Method of Polyolefin-Coated Fertilizer

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Pedosphere 2005年第4期15卷 491-498页

作者： TIAN Xiao-Hong M. SAIGUSA Laboratory of Environmental Crop science Field Science Centre Tohoku University Kawatabi Naruko Miyagi Prefecture 989-6711 （Japan）. college of Natural Resources and Environmental sciences Northwest Science and Technology University of Agriculture and Forestry Yangling Shaanxi 712100 （China）

The response of tomato （Lycopersicon esculentum） plants basically fertilized with 0.3 g N per plant of compound fertilizer with a N：P2O5：K2O ratio of 20：10：20 to sticks of polyolefin-coated fertilizer （POCF）（LongT0 with a N：P2Os：K2O ratio of 14：12：14） applied 23 d after transplanting was investigated using rooting boxes in the greenhouse. The results at 26 and 40 d after stick fertilizer treatment showed that the use of the stick fertilizer greatly increased the production of many new fine roots from the tomato plants. Compared to the unfertilized control, root length and root length density in the stick fertilizer treatment increased by 3.6-6.7 fold. In the soil zones near the stick fertilizer, root weight and root mass density were also significantly higher for the stick fertilizer treatment. Additionally, the use of the stick fertilizer increased the N, P and K concentrations in the leaves and stems of the tomato plants. The new fine roots growing near the stick fertilizer not only absorbed more nutrients and translocated them to the shoots, but also contained more nutrients within themselves. The soil ammonium and nitrate N data showed that N released from the stick fertilizer played a major role in inducing the production of new fine roots. These results indicated that stick fertilizer could be used as an alternative to the co-situs application technique to change and control the root distribution of crops as well as to increase the potential capacity of roots for water and nutrient absorption.

关键词： application method controlled release fertilizer tomato (Lycopersicon esculentum)

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