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Journal of University of Science and Technology Beijing 2007年第3期14卷 266-270页

作者： Hongyu Liu Xueming Ma dongmei jiang Wangzhou Shi College of Science Wuhan University of Science and Technology Wuhan 430081 China Department of Physics East China Normal University Shanghai 200062 China

Y2O3-doped ZnO-based varistor ceramics were prepared using high-energy ball milling （HEBM） and low-temperature sin- tering technique, with voltage-gradient of 1934-2197 V/mm, non-linear coefficients of 20.8-21.8, leakage currents of 0.59-1.04 μA, and densities of 5.46-5.57 g/cm3. With increasing Y2O3 content, the voltage-gradient increases because of the decrease of ZnO grain size; the non-linear coefficient and the leakage current improve but the density decreases because of more porosity; the donor con- centration and density of interface states decrease, whereas the barrier height and width increase because of the acceptor effect of Y2O3 in varistor ceramics.

关键词： inorganic materials electrical properties high-energy ball milling varistor microstructure low-temperature sintering zinc oxide yttrium oxide

Fabrication of ZnO-based thick film varistors with high potential gradient

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Rare Metals 2010年第4期29卷 390-395页

作者： KE Lei jiang dongmei MA Xueming State Key Laboratory of Precision Spectroscopy Department of Physics East China Normal University Shanghai 200062 China

ZnO-based thick film varistors have been fabricated by Y203 doping and low-temperature sintering, of which the sample with the best electrical properties has a high potential gradient value of 3159.4 V/mm. The effects of Y2O3 doping concentration and sintering temperature on the potential gradient of the samples were systematically investigated. The results show that the sample with the best electrical properties can be obtained by doping 0.08 mol% Y2O3 and sintering at 725℃. Under these optimum preparation conditions, the leakage current and the nonlinear coefficient are found to be 36.4 gA and 13.1. The sample with the best electrical properties has a grain size of 1.290um, a single grain boundary voltage of 4.08 V, a barrier height of 0.81 eV, and a depletion layer width of 10.2 nm, which are determined by thermionic emission. Small grain size with good grain boundary characteristics is beneficial to improve the electrical properties of varistors and promote the potential gradient.

关键词： condensed matter physics thick film varistors low-temperature sintering doping potential gradient

Integrated benefits of power generation by straw biomass--A case study on the Sheyang Straw Power Plants in jiangsu Province,China

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Frontiers of Environmental Science & Engineering 2009年第3期3卷 348-353页

作者： Xiaoshun LI Futian QU dongmei jiang Peixin ZHU China Centre for Land Policy Research Nanjing Agriculture UniversityNanjing 210095China

Power generation using straw biomass has quantifiable benefits from an economic,ecological,and sociological perspective in *** methods used to construct the assessment models of these integrated benefits were the revenue capitalization approach and the discounted-cash-flow *** results indicated that a straw power plant with the capacity of 2.50×10^(7)W and burning 1.23×10^(5)tons of cotton straw could annually supply 1.40×10^(8)kWh of ***,it would not be until six years later that these results could be *** the long term,the gross benefits could reach up to 4.63×10^(8)***,the total benefits are expected to be 1.18×10^(12)Yuan if all available straw resources are used to generate *** policy implication showed that the long-term integrated benefits of power generation by straw biomass outweighed the short-term *** is the main incentive to use straw biomass for power generation in the future.

关键词： straw biomass resources power generation renewable energy Sheyang county

Numerical simulation of the factors influencing dust in drilling tunnels:Its application

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Mining Science and Technology 2011年第1期21卷 11-15页

作者： Niu Wei jiang Zhongan Tian dongmei Key Laboratory of Ministry of Education for High Efficiency Exploitation and Safety of Metal Mine. Beijing University of Sdence and Technology Beijing 100083 China

Gas-solid two-phase flow theory was used to predict dust distribution and movement at the working face of a *** software package FLUENT was used to numerically simulate dust motion and the results were compared to observed *** simulation agrees with the data taken from an actual working face,which confirms the choice of mathematical model and numerical simulation method. Using the model we predict a set of conditions optimum for reducing dust concentrations at the mine working face.

关键词： Drivage working faceDust concentrationThe gas-solid two-phase flowVentilation method

The Roles of Countrywomen in Controlling Non-point Source Pollution

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Chinese Journal of Population,Resources and Environment 2006年第2期4卷 28-32页

作者： jiang dongmei Zhou Yuanfang Lu Genfa School of Environment Nanjing University Nanjing 210093 China Philosophy and Religion Department Nanjing University Nanjing 210093 China

The main causes of non-point source pollution in Taihu Lake are the improper ways of crop production, animal husbandry, and daily runoff. The paper discusses the relationship between countrywomen and non-point source pollution control by 731 questionnaires in Weidu village and 466 questionnaires in Dapu Town. The roles of countrywomen have changed in families and they have close relationship with non-point source pollution. Furthermore, we discuss the possibility and methods of organizing countrywomen in non-point source pollution control.

关键词： countrywomen non-point source pollution control role

Roles of State Strategy of Adaptation to Climate Change in China

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Chinese Journal of Population,Resources and Environment 2007年第4期5卷 74-80页

作者： jiang dongmei Wang Can Huang Shanfeng Zhang Mengheng Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Pollution Control and Resource Reuse College of Environment Nanjing University Nanjing Jiangsu 210093 China Department of International Cooperation State Envi＇ronmental Protection Administration of China Beijing 100035 China

For the adverse impacts of climate change, China gov- ernment should place the problem of adaptation to climate change on the agenda. It is time to institute and implement a state adap- tive strategy to reduce the adverse impacts on economy, commu- nity and people's health and life by international cooperation and our own endeavor. A state strategy of adaptation to climate change should be closely linked with other current interrelated national strategies, and they should be supplemented and improved by each other. This paper discusses the roles of the state strategy of adaptation to climate change in the state climate change integra- tive strategy, the environmental protection strategy, and the sus- tainable development strategy in China. Furthermore, it proposes the main aims of the state adaptive strategy of China.

关键词： adaptation to climate change state strategy roles

Study on agricultural structure and non-point source pollution: a case in Dapu Town of Yixing City

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Ecological Economy 2006年第3期2卷 270-280页

作者： jiang dongmei Wang Xiyuan Liu Minghui Lu Genfa School of the Environment Nanjing University Nanjing 210093 P. R. China Nankai University Tianjin 300071 P. R. China

The water body of Taihu Lake has been eutrophicated because of area-source pollution. 83% of the total nitrogen and 84% of the total phosphorus of the pollutant that have washed into Taihu Lake originated from the fertilizer of crop land, rural animal husbandry and living sewage and rubbish in rural area. The goal of adjusting agricultural structure is to improve agricultural development, and to increase the peasants＇ income by planting non-grain crop, centralizing animal husbandry, and intensifying aquaculture, etc. It is necessary to research on the influences of agriculture industrial structure on area-source pollution. This paper studies a case of Dapu Town in Yixing City, which is a typical drainage place beside Taihu Lake. On the basis of the analysis on the status quo of area-source pollution and agriculture industrial structure in Dapu Town, the conflicts between them are discussed. Non-grain crop production with a great deal of fertilizer and developing aquaculture with a great deal of organic pollutant, which are directly discharged, make area-source pollution more serious and accelerate the eutrophication in Taihu Lake. This paper suggests taking corresponding technological measures and policies, which have been tested in Dapu Town and demonstrated in Taih, Lake area.

关键词： Taihu Lake Area-source pollution Agricultural industrial structure Countermeasures

Driving mechanism and boundary control of urban sprawl

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Frontiers of Environmental Science & Engineering 2015年第2期9卷 298-309页

作者： dongmei jiang Xiaoshun LI Futian QU Mingyan LI Shaoliang ZHANG Yunlong GONG Xiaoping SHI Xin CHEN School of Environment and Spatial Informatics China University of Mining & Technology Xuzhou 221116 China College of Public Administration Nanjing Agricultural University Nanjing 210095 China Institute of Economics Zhejiang Academy of Social Sciences Hangzhou 310025 China

Since the reform and opening-up, China＇s economy has achieved remarkable development and so does the urbanization. However, there is an unavoidable contradiction between urban sprawl and the protection of arable land and the environment. By redefining the urban sprawl boundary, this paper is to provide a solution for the conflict above on the China＇s urbanization context. The ideal boundary, moderate boundary and limit boundary are defined for urban sprawl in space. Taking Nanjing city as a case, the three urban sprawl boundaries are estimated in this paper based on the calculation of agricultural land resources value in Nanjing. The results show that 1） the integrated value of agricultural （cultivated） land resources in Nanjing is 1.55× 10^7 CNg·hm^-2, the economic value accounts for only 8.74% of the integrated value, while 91.26% of the integrated value has not revealed itself due to the existing institutional arrangements, policy distortions, and imperfect land market; 2） it is difficult to define the ideal and moderate boundaries due to the relatively low price of North Nanjing. In South Nanjing the land price is expensive and the ideal, moderate and limit boundaries are expanded to jiangning, Qixia, and Yuhuatai; 3） the city scale of South Nanjing should be limited within 5.82 × 10^4 hm^2, which is roughly the same as the designated size of 5.81 × 10^4 hm^2 in the urban planning. It is suggested that the rational scope of urban expansion should be controlled within the moderate boundary.

关键词： urban sprawl rational expansion drivingforces boundary control Nanjing

Countermeasures of adaptation to climate change:establishment and application for implementation matrix

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Ecological Economy 2009年第2期5卷 102-111页

作者： jiang dongmei Liu Bin Institute of Energy Environment and Economy Tsinghua University Beijing 100084 P. R. China

In the conceptual framework of adaptation policy assessment to climate change, adaptation measures can be categorized as two groups：facilitation and implementation. Facilitation measures refers to activities that enhance adaptive capacity, while implementation refers to activities that actually avoid adverse climate impacts on a system by reducing its exposure or sensitivity to climatic hazards, or by moderating relevant non-climatic factors. This paper aims to establish a matrix of implementation measures of adaptation to climate change, through four different ways how adaptation can influencc the relevant elements of climate change. reducing the exposure, reducing the sensitivity, alleviating the adverse impacts and reducing the negative non-climatic factors, and then further discuss the particular implementation measures of adaptation to climate change, through application studies on the selected sub-systems, intend to organize the disordered implementation measures in existent, and put forward some new measures under the guidance of this matrix, which could enrich and promote the system and content of implementation measures of adaptation.

关键词： Adaptation to climate change hnplementation of adaptation, Matrix of implementation

Experimental Evidence of Radiation Amplification Without Population Inversion in Sodium Atoms

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Chinese Physics Letters 1992年第11期9卷 589-592页

作者： GAO Jinyue GUO Chuan JIN Guangxu GUO Xinzhen WANG Qingwen ZHANG Hanzhuang ZHAO Jian jiang Yun WANG Dezhong jiang dongmei Department of Physics Jilin UniversityChangchun 130023 Changchun Institute of Applied Chemistry Academia SinicaChangchun 130022

We have demonstrated a radiation amplification without population inversion in sodium according to a four-level model,which was recentlyproposed by Nor-ducci et *** amplified radiation signal at 589.0nm has been observed when an intense coherent driving field at 589.6nm was on and an incoherent pumping process from the ground state 3S_(1/2) to 3P_(3/2) excited state was operating.

关键词： pumping driving intense