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Evapotranspiration, Yield and Crop Coefficient of Irrigated Maize Under Straw Mulch

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Pedosphere 2005年第5期15卷 576-584页

作者： ZHANG Xi-ying CHEN su-ying PEI Dong LIU Meng-Yu suN Hong-Yong Shijiazhuang Institute of Agricultural Modernization Chinese Academy of Sciences Shijiazhuang 050021 （China）

Maize (Zea mays L.), a staple crop grown from June to September during the rainy season on the North China Plain,is usually inter-planted in winter wheat (Triticum aestivum L.) fields about one week before harvesting of the winterwheat. In order to improve irrigation efficiency in this region of serious water shortage, field studies in 1999 and 2001, twodry seasons with less than average seasonal rainfall, were conducted with up to five irrigation applications to determineevapotranspiration, calculate the crop coefficient, and optimize the irrigation schedule with maize under mulch, as well asto establish the effects of irrigation timing and the number of applications on grain yield and water use efficiency (WUE)of maize. Results showed that with grain production at about 8 000 kg ha-1 the total evapotranspiration and WUE ofirrigated maize under mulch were about 380-400 mm and 2.0-2.2 kg m-3, respectively. Also in 2001 WUE of maizewith mulch for the treatment with three irrigations was 11.8% better than that without mulch. In the 1999 and 2001seasons, maize yield significantly improved (P = 0.05) with four irrigation applications, however, further increases werenot significant. At the same time there were no significant differences for WUE with two to four irrigation *** the 2001 season mulch lead to a decrease of 50 mm in the total soil evaporation, and the maize crop coefficient undermulch varied between 0.3-1.3 with a seasonal average of 1.0.

关键词： crop coefficient maize mulch water use efficiency

The Prevalence of HIV Drug Resistance among Treatment-failure Individuals and Treatment-nave Individuals in China:A Meta-analysis

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Biomedical and Environmental Sciences 2014年第11期27卷 858-871页

作者： WU Jing NORRIS Jessie LIU Hui Xin LI Zheng su ying ying ZHU Lin WANG Ning National Center for AIDS/STD Control and Prevention China Center for Disease and Prevention School of Agroforestry & Medicine the Open University of China

Objective To understand drug resistance prevalence among treatment-failure and treatment-nave HIV-positive individuals in *** We searched five electronic databases（Wanfang,CNKI,CQVIP,SinoMed,and Pubmed） for studies of HIV drug ***-effects models were carried out to estimate the prevalence of drug resistance among treatment-failure and treatment-nave individuals,*** The estimated nationwide rates of HIV drug resistance to any-class drugs among treatment-failure and treatment-nave individuals were 57%（95% CI：49%-65%） and 3.23%（95% CI：2.47%-4.07%）,*** the drug classes,the prevalence of resistance to PIs was low（1.45%;95% CI：0.73%-2.33%） in treatment-failure individuals,although high rates of resistance to NNRTIs（54%;95% CI：45%-63%） and NRTIs（40%;95% CI：32%-49%） were *** to any-class drugs,NNRTIs and NRTIs manifested regional differences,but resistance to PIs did *** correlations were observed between resistance to NNRTIs and NRTIs among treatment-failure and treatment-nave individuals,*** The prevalence of HIV drug resistance to NNRTIs and NRTIs among treatment-failure individuals was *** contrast,the prevalence of drug resistance among treatment-nave individuals was *** epidemics of drug resistance matched current treatment strategies and interventions in *** for HIV drug resistance is necessary to assess the sustainability and durability of current treatment regimens.

关键词： HIV Drug resistance Meta-analysis China

Dielectric Spectroscopy Study on Vesicles of CTAB/SDBS System

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Chinese Chemical Letters 2001年第1期12卷 91-94页

作者： su Xiang WEI ying LI Kong Shuang ZHAO Department of Chemistry South China Normal UniversityGuangzhou 510631

Amphiphilic molecules can form into different structures, such as micelle, microemulsion, vesicle, liposome, liquid crystals, and so on by self-associating. The Dielectric Spectroscopy (DS) method has been applied to the systems of micelle and microemulsion successfully. For the first time the author put the method to the system of vesicle of CTAB/SDBS. The experiments show clear dielectric relaxation and the results were discussed primarily.

关键词： Dielectric spectroscopy vesicle macroscopic relaxation time

sustainable Lignin-Derived Carbon as Capacity-Kinetics Matched Cathode and Anode towards 4.5 V High-Performance Lithium-Ion Capacitors

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Energy & Environmental Materials 2023年第4期6卷 98-105页

作者： Fangyan Liu Pengfei Lu ying Zhang Feng su Liangzhu Zhang Shuanghao Zheng Xiong Zhang Fangyuan su Yanwei Ma Zhongshuai Wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023China Anhui Key Laboratory of Spin Electron and Nanomaterials School of Chemistry and Chemical EngineeringSuzhou UniversitySuzhou 234000China University of Chinese Academy of Sciences Beijing 100049China CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China Institute of Electrical Engineering and Advanced Electromagnetic Drive Technology Qilu ZhongkeJinan 250013China

The Li-ion capacitors(LICs)develop rapidly due to their double-high features of high-energy density and high-power ***,the relative low capacity of cathode and sluggish kinetics of anode seriously impede the development of ***,the precisely pore-engineered and heteroatomtailored defective hierarchical porous carbons(DHPCs)as large-capacity cathode and high-rate anode to construct high-performance dual-carbon LICs have been *** DHPCs are prepared based on triple-activation mechanisms by direct pyrolysis of sustainable lignin with urea to generate the interconnected hierarchical porous structure and plentiful heteroatominduced *** from these advanced merits,DHPCs show the well-matched high capacity and fast kinetics of both cathode and anode,exhibiting large capacities,superior rate capability and long-term *** experimental and computational results demonstrate the strong synergistic effect of pore and dopants for Li ***,the assembled dual-carbon LIC exhibits high voltage of 4.5 V,high-energy density of 208 Wh kg^(−1),ultrahigh power density of 53.4 kW kg^(−1)and almost zerodecrement cycling ***,the full device with high mass loading of 9.4 mg cm^(−2)on cathode still outputs high-energy density of 187 Wh kg^(−1),demonstrative of their potential as electrode materials for high-performance electrochemical devices.

关键词： capacity-kinetics matching defective hierarchical porous carbons high mass loading high power density Li-ion capacitors

Development and Application of On-line Wind Power Risk Assessment System

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电力系统自动化 2012年第8期36卷 161-165页

作者： su, Feng Zhou, Xiaoxin Yu, Haiguo Xian, Wenjun Lü, ying Ren, Lingyu Power System Department China Electric Power Research Institute Beijing 100192 China Qinghai Electric Power Dispatch Center Xining 810008 China

Because of the large-scale integration of wind power,the dynamic characteristics of power system have many uncertain *** on deterministic analysis methods,traditional on-line security assessment system cannot quantitatively estimate the actual operating conditions of the power system for only considering the most serious and credible ***,the risk theory is introduced into an on-line security assessment system and then an on-line risk assessment system for wind power is designed and implemented by combining with the dynamic security assessment *** on multiple data integration,the wind power disturbance probability is available and the security assessment of the power grid can obtain security indices in different *** operating risk index is an expectation of severity,computed by summing up all the products of the result probability and its *** results are reported to the dispatchers in on-line environment,while the comprehensive weak links are automatically provided to the power dispatching *** risk assessment system in operation can verify the reasonableness of the system.

关键词：安全评估系统风力发电系统风险理论应用开发定性分析方法动态安全评估电力调度中心

Bedform development and its effect on bed stabilization and sediment transport based on a flume experiment with non-uniform sediment

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International Journal of Sediment Research 2017年第3期32卷 305-312页

作者： su-Chin Chen Chia-Ning Yang Ching-ying Tsou Department of Soil and Water Conservation National Chung Hsing University Sinotech Engineering Consultants LTD. Department of Agricultural and Environmental Engineering Faculty of Agriculture and Life Science Hirosaki University

Non-uniform sediment deposited in a confined, steep mountain channel can alter the bed surface composition. This study evaluates the contribution of geometric and resistance parameters to bed stabilization and the reduction in sediment transport. Flume experiments were done under various hydraulic conditions with non-uniform bed material and no sediment supply from upstream. Results indicate that flume channels respond in a sequence of coarsening and with the formation of bedformroughness features such as rapids, cascades, and steps. A bedform development coefficient is introduced and is shown to increase(i.e. vertical sinuosity develops) in response to increasing shear stress during the organization process. The bedform development coefficient also is positively correlated with the critical Shields number and Manning’s roughness coefficient, suggesting the evolution of flow resistance with increasing bedform development. The sediment transport rate decreases with increasing bed shear stress and bedform development, further illustrating the effect of bed stabilization. An empirical sediment transport model for an equilibrium condition is proposed that uses the bedform development coefficient, relative particle submergence(i.e. the ratio of mean water depth and maximum sediment diameter), modified bed slope, and discharge. The model suggests bedform development can play a primary role in reducing sediment transport(increasing bed stabilization). The model is an extension of Lane’s(1955) relation specifically adapted for mountain streams. These results explain the significance of bedform development in heightening flow resistance, stabilizing the bed, and reducing sediment transport in coarse, steep channels.

关键词： Bedform development Bed stabilization Sediment transport Non-uniform bed

Storage and transfer of optical excitation energy in GaInP epilayer:Photoluminescence signatures

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Journal of Materials Science & Technology 2019年第7期35卷 1364-1367页

作者： Shijie Xu ying Huang Zhicheng su Rongxin Wang Jianrong Dong Deliang Zhu Department of Physics and Shenzhen Institute of Research and Innovation (HKU-SIRI)The University o f Hong KongPokfulam RoadHong KongChina Vacuum Interconnected Nanotech Workstation Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of SciencesSuzhou215123China Guangdong Research Center for Interfacial Engineering of Functional Materials and College of Materials Science and EngineeringShenzhen UniversityShenzhen518060China

GaInP alloy could be the most trusted key material for fabricating super-high-efficiency single-and multijunction solar cells, especially for space applications. The storage and transfer of optical excitation energy in this key alloy is thus a key subject of the energy conversion from optical to electrical. In this article we present a study of the subject through investigating photoluminescence(PL) degradation in the GaInP epilayer at 4 K under the continuous optical excitations of ultraviolet(UV) 325 nm, visible 488.0 and 514.5 nm lasers. It is found that the decline of PL intensity with the irradiation time may be represented by I(t)/I0=(1 + tτ-1)-1+C, where I0 is the luminescence intensity at the beginning of irradiation, a time constant, and C a background. Moreover, the PL degradation degree reduces with increasing the excitation wavelength. In addition, some red shift of the PL peak is observed accompanying with the intensity decline under the UV laser excitation. These PL signatures indicate that the localized carriers within the local atomic ordering domains play a major role in the storage and transfer of the excitation energy via photon recycling processes.

关键词： GaInP alloy Photoluminescence Energy transfer Photon recycling

Ultrasensitive Electrochemical Aptasensor Based on surface-Initiated Enzymatic Polymerization

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Chinese Journal of Chemistry 2016年第3期34卷 337-341页

作者： Pengjuan Wang ying Wan Yan su Shengyuan Deng Shulin Yang Sehool of Mechanical Engineering Nanjing University of Science and Technology Nanjing Jiangsu 210094 China School of Environmental and Biological Engineering Nanjing University of Science and Technology Nanjing Jiangsu 210094 China

Coupled with the ability of fast and quantitative response, electrochemical aptasensors （EA） have great potential in the application of early diagnosis of cancer biomarker. In order to determine the rare hiomarkers in the compli- cate clinical samples, scientists are making unremitting efforts towards improving the sensitivity and selectivity of EA. Herein, a ＂sandwich＂-strucmre electrochemical aptasensor （SEA） is developed for analysis of cancer biomarker carcino-embryonic antigen （CEA）. Two DNA aptamers are employed, one of which is thiolated at Y-terminal and immobilized onto the gold electrode as a capture probe, while the other one is served as signal probe. The two ap- tamers could ＂sandwich＂ the target and signal probe is then subjected to the terminal deoxynucleotidyl transferase （TdT）-catalyzed incorporation of biotin labeled dNTPs into its 3＇-terminal. Thus the as-generated long DNA oligo tails allow specific binding of numerous avidin modified horseradish peroxidase （Av-HRP）, resulting in enhanced peroxidase catalyzed electrochemical signals. This signal amplification strategy is termed as surface initiated enzy- matic polymerization （SIEP）. This SIEP amplified SEA has a detection limit of 10 pg·mL^-1, indicating the out- standing amplification efficiency.

关键词： electrochemical aptasensor terminal deoxynucleotidyl transferase surface initiated enzymaticpolymerization "sandwich"-structure sensitive

Effect of different molecular weight organic components on the increase of microbial growth potential of secondary effluent by ozonation

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Journal of Environmental Sciences 2014年第11期26卷 2190-2197页

作者： Xin Zhao Hong-ying Hu Tong Yu Chang su Haochi Jiang Shuming Liu Environmental Simulation and Pollution Control State Key Joint Laboratory School of Environment Tsinghua University State Environmental Protection Key Laboratory of Microorganism Application and Risk Control Graduate School at Shenzhen Tsinghua University College of Environment and Resources Inner Mongolia University

Ozonation has been widely applied in advanced wastewater treatment. In this study, the effect of ozonation on assimilable organic carbon （AOC） levels in secondary effluents was investigated, and AOC variation of different molecular weight （MW） organic components was analyzed. Although the removal efflciencies were 47%-76% and 94%-100% for UV2s4 and color at ozone dosage of 10 mg/L, dissolved organic carbon （DOC） in secondary effluents was hardly removed by ozonation. The AOC levels increased by 70%-780% at an ozone dosage range of 1-10 mg/L. AOC increased significantly in the instantaneous ozone demand phase, and the increase in AOC was correlated to the decrease in UV254 during ozonation. The results of MW distribution showed that, ozonation led to the transformation of larger molecules into smaller ones, but the increase in low MW （〈1 kDa） fraction did not contribute much to AOC production. The change of high MW （〉100 kDa and 10-100 kDa） fractions itself during ozonation was the main reason for the increase of AOC levels. Furthermore, the oxidation of organic matters with high MWs （〉 100 kDa and 10-100 kDa） resulted in more AOC production than those with low MWs （1-10 kDa and 〈1 kDa）. The results indicated that removing large molecules in secondary effluents could limit the increase of AOC during ozonation.

关键词： Wastewater reclamation and reuse Ozonation Assimilable organic carbon (AOC)Molecular weight distribution Biological stability