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Synthesis and Crystal Structure of Tetraaquacopper(II) Bis(5-fluorouracil-1-acetate) Tetrahydrate

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Chinese Journal of Structural Chemistry 2006年第5期25卷 562-566页

作者： wang wei-dong HU Mao-Lin Hubei Key Laboratory of Bioanalytical Technique Hubei Normal University Huangshi Hubei 435002 China Department of Chemistry and Environmental Engineering Hubei Normal University Huangshi Hubei 435002 China School of Chemistry and Materials Science Wenzhou University Wenzhou 325027 China

The title compound, [Cu（C6H4N2O4F）2（H2O）4].4（H2O） I, has been hydrothermally synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in monoclinic, space group P21/c with a = 8.3041（17）, b = 12.045（2）, c = 11.077（2） A, β = 92.567（3）°, V= 1106.8（4） A^3, Mr = 581.89, Z= 2, Dc = 1.746 g/cm^3, F（000） = 598,μ（MoKa） = 1.090 mm^-1, the final R = 0.0296 and wR = 0.0806 for 3195 observed reflections with Ⅰ 〉 2σ（Ⅰ）. In the centrosymmetric compound I, each Cu（Ⅱ） ion is coordinated by six O atoms from two 5-fluorouracil-1-acetate anions and four water molecules, forming a six-coordinated octahedral environment. N-H…O and O-H…O hydrogen-bonding interactions are observed in the structure, leading to the formation of a three-dimensional network.

关键词： copper crystal structure 5-fluorouracil-1-acetate

Compromises of Bali Roadmap

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Chinese Journal of Population,Resources and Environment 2008年第3期6卷 27-32页

作者： wang Jingmin wei dong School of Business Administration Shandong University of Finance Jinan Shandong 250002 China

The Bali Roadmap, as the breakthrough on intergovernmental negotiation of climate change mitigation, having brought United States on track, is still a result of compromises. The major compromises of the Bali Roadmap are centered around three issues of quantifying emission reduction targets, developing countries’ obligations as well as quantifying devel- oped countries’ financial assistance in developing countries' capacity building on climate change. It is found that the rationalities behind these compromises are the national interests. Due to the fact, achieving cohesion among all nations in climate change actions is very difficult. Therefore, the Bali Roadmap may lead to a tough way with distant hope. However, technology innovation and well-designed economic instruments would be helpful and supportive for further international negotiation and cooperation.

关键词： Bali Roadmap climate change international agreement carbon market capacity building

Research on the novel asymmetric frequency division duplex technique

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 13-18页

作者： ZHANG Ying-hai wang wei-dong dong Yu ZHOU Kai-Jie Information and Electronics Technology Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

This article introduces a novel duplex transmission technique-asymmetric frequency division duplex （AFDD）. One of the characteristics in future mobile systems is asymmetric characteristic caused by service requirement and electromagnetic radiation, AFDD is designed to adapt to the new asymmetric characteristics. The AFDD puts forward a novel adaptive frequency-allocation scheme in downlink and uplink. Combining AFDD with code division multiple access （CDMA） communication system, it is proven that AFDD improves the capacity and coverage of the system compare with FDD CDMA system.

关键词： asymmetric characteristics AFDD Duplex Mobile communications

The power of informal institutions:The impact of clan culture on the depression of the elderly in rural China

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Journal of Integrative Agriculture 2021年第4期20卷 1107-1118页

作者： LIU Xiao-hong wang wei-dong ZHANG Lin-xiu China Center for Agricultural Policy School of Advanced Agricultural SciencesPeking UniversityBeijing 100871P.R.China School of Economics and Management Beijing Forestry UniversityBeijing 100083P.R.China UN Environment-International Ecosystem Management Partnership(UNEP-IEMP) Beijing 100101P.R.China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China

Exploration of ways to improve the subjective welfare of residents is an important area of current academic *** data from the China Family Panel Studies survey conducted in 2010,this paper investigated the impact of clan culture on the mental health of elderly people in rural *** results demonstrated that clan culture can significantly decrease the depression score of the rural ***,there was no gender difference with respect to the impact of clan culture on the depression score of the *** the same time,the positive effects of clan culture on the depression score of the elderly have gradually weakened with economic *** of the mechanisms involved indicated that in areas with stronger clan culture,older people receive more social *** study enriches our understanding of the impact of informal institutions on the welfare of rural *** the same time,it can also provide a certain decisionmaking reference for the government to formulate relative poverty relief strategies in a new stage of poverty alleviation.

关键词： clan culture the elderly depression rural China social support

A channel estimation algorithm for optical orthogonal frequency division multiplexing systems

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Optoelectronics Letters 2013年第3期9卷 217-220页

作者： wang dong YOU Nian-yu wang wei-dong ZHANG Ying-hai Laboratory of Information and Electronics Technology Beijing University of Posts and Telecommunications Bei-jing 100876 China Research Institute of Photonics Dalian Polytechnic University Dalian 116034 China

A simple channel estimation (CE) scheme, which is pilot-aided with just a little number of pilots inserted in the first half part of the subcarriers, is proposed and simulated for resisting the fiber dispersion in optical orthogonal frequency division multiplexing (OFDM) systems. The simulation results verify that the receiver sensitivity is improved by 2-3 dBm for bit error rate (BER) of 10~(-3) with the proposed CE algorithm than that with other kinds of CE algorithms based on linear square principle. The good constellation performance for a 40 Gbit/s transmission system can be also obtained by the proposed scheme.

关键词：正交频分复用系统信道估计算法接收灵敏度 OFDM 仿真结果传输系统子载波飞行员

Impact pressure of debris flow on beam dam

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Journal of Mountain Science 2023年第10期20卷 2822-2834页

作者： wang dong-wei YOU Yong LIU Jin-feng SUN Hao wang Zhuang Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of SciencesChengdu 610041 China Institute of Mountain Hazards and Environment CASChengdu 610041China University of Chinese Academy of Science Beijing 100049China

The use of open-type check dams in mountainous areas has become common practice in order to mitigate the effects of debris flow and extend the service life of engineering *** beam dam,a common debris flow control system,has received less attention in research on the impact process of debris flow and check dams compared to solid check ***,the estimation of impact pressure in debris flow primarily considers debris flow characteristics,without taking into account the influence of geometric characteristics of the transmission *** better understand the impact process of debris flow on beam dams,a series of small-scale debris flow impact tests were conducted in a model *** parameters,including velocity,depth,and impact pressure,were *** results show that the maximum impact pressure of debris flow is affected by both the characteristics of the debris flow and the relative opening size of the beam *** to flow and edge occlusion in the middle of the beam dam,the discharge of debris flow is enhanced,resulting in a longer impact process and higher maximum impact *** on these findings,a calculation model of the maximum impact pressure of debris flow at the midpoint of the middle beam is proposed,which can be used to estimate the impact of debris flow on the discharge part of the beam dam.

关键词： Debris flow Beam dam Impact pressure Relative opening size Calculation model

Improving Breakdown Behavior by Substrate Bias in a Novel Double Epi-layer Lateral Double Diffused MOS Transistor

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Chinese Physics Letters 2012年第2期29卷 190-192页

作者： LI Qi wang wei-dong LIU Yun wei Xue-Ming Guangxi Key Laboratory of Wireless Wideband Communication&Signal Processing Guilin University of Electronic TechnologyGuilin 541004

A new lateral double diffused MOS (LDMOS) transistor with a double epitaxial layer formed by an n-type substrate and a p-type epitaxial layer is reported (DEL LDMOS).The mechanism of the improved breakdown characteristic is that the high electric field around the drain is reduced by substrate reverse bias,which causes the redistribution of the bulk electric field in the drift region,and the vertical blocking voltage is shared by the drain side and the source *** numerical results indicate that the trade-off between breakdown voltage and on-resistance of the proposed device is improved greatly in comparison to that of the conventional LDMOS.

关键词： breakdown drain LDMOS

Study on Applying Optimal Path to Land Valuation

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Geo-Spatial Information Science 2006年第1期9卷 49-54页

作者： wang wei dong Fei SHI Lite CAO Fang State Key Laboratory of Information Engeering in Surveying. Mapping and Remote Sensing. Wuhan University 129 Luoyu Road Wuhan 430079 China

As an important role in the urban land price system, the basic land price appraisal directs and refleets all kinds of land price in the real estate market. Using geographic information systems （GIS） with algo rithms and powerful analysis functions to valuate land will improve the rationality and convenience of land valu- ation. The objective of the study on basic land price using the optimal path algorithm is to decrease the man made error, enhance automatization, avoid make inconvenience by roadblock object.

关键词： GIS optimal path shortest path land price appraisal land valuation basic land price

Effects of cultivation conditions on the diversity of microbes involved in the conversion of rice straw to fodder

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Journal of Environmental Sciences 2007年第1期19卷 67-73页

作者： YANG Hong-yan GAO Li-juan wang Xiao-fen wang wei-dong CUI Zong-jun College of Agronomy and Biotechnology China Agricultural University Beijing 100094 China

To confirm the optimum cultivation conditions for analyzing lactic acid bacterial communities and to provide the cultivation foundation for lactic acid bacterial communities that were used to convert straw into fodder, fermented rice straw was inoculated into 13 different broths. After 48 h of cultivation, pH values, volatile products, and microbial diversity were analyzed. Except for LAB broth, the pH values of the other broths could decrease to approximately 4.5. GC/MS analysis showed that lactic acid in Tomato MRS broth, MRS broth, LAB broth, and Tomato juice broth was higher than that in the other broths. DNA concentration analysis showed that the counts of microbes in Tomato MRS broth were 2.5 times of those in other broths and that tomato juice favored the reproduction of the microbes. Denaturing gradient gel electrophoresis （DGGE） analysis showed that the number of lactic acid bacterial species in HYA broth, Tomato juice broth, and Tomato MRS broth were higher than those in the other broths.

关键词： straw cultivation condition microbial diversity DGGE