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Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in Beijing, China

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Science China Earth Sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1. LIANG Tao1.& TAO shu2 1. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 1.01.1. China 2. Laboratory for Earth Surface Processes, Peking University, Beijing 1.0871. China 1. Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking Beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1.52―2003 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1.52―1.83, the average input and output amount of HCHs through agricultural application and degradation are 1.0 t and 1.0 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1. 1. t?a?1.and 1. t?a?1. which account for 92% of total transfer fluxes of HCHs isomers. There were approximately 253t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1.84 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1.83, and this percentage may descend to 0.5% after 20 years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

The Optimum Model and Its Decision Support System of Coal Quality Balance

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Systems Science and Systems Engineering 2000年第1期10卷 87-92页

作者： MENG Xiang\|rui\+1.\ shu Hang\+2 1. Huainan Institute of Technology, Huainan 232001. China 2. State Plan Council, Beijing 1.0824, China

The meaningfulness and significance of coal quality balance have been summarized in this paper and practical steps concerning constructing the synthetic tech\|economic model and its decision support system of coal quality balance using the optimization technique of inverse recurrence of established initializing parameters have also been introduced. The principles and methods as applied in the model system development and procedure construction have been discussed accordingly.

关键词： coal quality balance tech\|economic model decision support system

TEUPERNIN D: A CHLORINE-CONTAINING NEO-CLERODANE DITERPENE FROM TEUCRIUM PERNYI

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Chinese Chemical Letters 1991年第11期2卷 845-846页

作者： Ning XIE~1. Zhi Da MIN~1. Shou Xun ZHAO~1. Yang LU~2 Qi Tai ZHENG~2 and Chun shu WANG~2 1. Department of Phytochemistry, China Pharmaceutical University, Nanjing, 21.009 2. Institute of Materia Medica, Chinese Academy of Medicinal Sciences, Beijing. 1.0050

A new chlorine-containing neo-clerodane diterpene, teupernin D, was isolated from the aerial parts of Teucrium pernyi. The structure for teupernin D was established as (1.S) -1., 1.-epoxy-8β-hydroxy-1.-chloro-1.-nor1.α-neo-cleroda-4, 1.(1.), 1.-triene-1.,6β;20,1.-diolide on the basis of spectral evidence. The absolute configuration was established by CD spectrum and confirmed by X-ray crystallographic analysis.

关键词： NEO TEUPERNIN D A CHLORINE-CONTAINING NEO-CLERODANE DITERPENE FROM TEUCRIUM PERNYI

DYNAMIC CHANGES OF THE WETLAND AND ITS DRIVING FORCES IN FUJIN REGION IN SANJIANG PLAIN,CHINA

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湿地科学 2005年第3期3卷 176-182页

作者： WANG Zhi-Qiang~1.2, CHEN Ming~1.2,WANG Dan-Dan~1.2 , ZHANG Bai~1.ZHANG shu-Qing~1.1. Northeast Institute of Geography and Agricultural Ecology, the Chinese Academy of Sciences,Changchun Jilin 1.001., China 2. Graduate School of Chinese Academy of Sciences, Beijing 1.0039, China ) Northeast Institute of Geography and Agricultural Ecology the Chinese Academy of SciencesChangchun Jilin 130012China Graduate School of Chinese Academy of Sciences Beijing 100039China Northeast Institute of Geography and Agricultural Ecology the Chinese Academy of SciencesChangchun Jilin 130012China

Wetland is a kind of key natural resources. However, the wetlands have been shrinking rapidly in Sangjiang Plain and its functions have been degrading. These all hold back the sustainable development of human communities, and lead to great change in the land use /cover (LUCC), consequently caused global changes in climate, water cycling, etc.. Taken Fujin region as a case study, spatial and temporal dynamic processes of wetland and its driving forces were analyzed from 1.54 to 2000 in this paper. It showed that the wetlands had been reduced from 52×1.4 ha to 1.×1.4 ha in areas during the nearly 50 years . The percentage of wetland areas reduced from 61.27% to 1..39%. On the other hand, cultivated land increased from 22×1.4 ha to 60×1.4 ha in areas. The percentage of the areas increased from 25.31. to 70.45%. Further quantitative analysis of the wetland landscape conversion characteristics and the correlation analysis between the change of wetland areas and population increase were made. The results showed that 40×1.4 ha wetlands had been converted to cultivated land within half of a century; the correlation between the rate of wetland loss and that of population increased is nearly -0.922. So it was concluded that the main driving force of wetland shrinkage in Fujin region was the colonization of human being.

关键词：湿地动态变化三江平原生态系统生态环境

Gold Distribution in Tellurium-Rich Pyrite and Tellurides from the Xiaoqinling Gold District,Southern Margin of the North China Craton

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矿物学报 2009年第S1期29卷 113-114页

作者： BI Shi-jian1.2,LI Jian-wei1.2,LI Zhan-ke1.2,ZHANG Su-xin1.ZHENG shu1.1. State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,430074 Wuhan,China 2. Faculty of Earth Resources,China University of Geosciences,430074 Wuhan,China)

Gold is commonly associated with arsenic in As-rich pyrite or arsenopyrite in a variety types of gold deposit,such as sediment-hosted gold deposits,epithermal Au-Ag deposits,Au-rich VMS deposits,and mesothermal lode g... 详细信息

关键词： Gold Distribution in Tellurium-Rich Pyrite and Tellurides from the Xiaoqinling Gold District,Southern Margin of the North China

Unification of national surveying vertical datum

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中国有色金属学会会刊：英文版 2005年第S1期15卷 9-12页

作者： YIN Xiao-dong~(1. 2), HU Jia-sheng~1. ZHANG Li-hua~2, LI shu-jun~2 (1. School of Telecommunication, Dalian University of Technology, Dalian 1.6024, China 2. Department of Ocean Surveying, Dalian Naval Academy, Dalian 1.601., China) Dalian Univ Technol Sch Telecommun Dalian 116024 Peoples R China Dalian Naval Acad Dept Ocean Surveying Dalian 116018 Peoples R China

The vertical datum of China is composed of leveling datum for heights and chart datum for depths. The determination of national leveling datum and its disadvantages were discussed firstly. The local mean sea level and chart datum with its guarantee rate of navigation safety were studied secondly. The models of unification of national surveying vertical datum, such as optimization model of mean sea level, adoption of New Chinese quasi-geoid of 2000(CQG2000) and time-invariant global geoid were suggested finally.

关键词： vertical datum leveling datum chart datum geoid quasi-geoid

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支持动态企业模型的MAS模型及其获取方法

系统工程理论与实践 2001年第5期21卷 44-49,97页

作者：龚报钧王树青浙江大学工业控制技术国家重点实验室

为了提高企业信息系统的柔性 ,本文首先提出了一种支持动态企业模型的多 Agent系统( MAS)模型 ,该模型包括两层 :组织结构层和业务处理层 .由于充分利用了 MAS所具有的自主能力、社交能力、反应能力和行为理性等特点 ,该模型能根据企业... 详细信息

为了提高企业信息系统的柔性 ,本文首先提出了一种支持动态企业模型的多 Agent系统( MAS)模型 ,该模型包括两层 :组织结构层和业务处理层 .由于充分利用了 MAS所具有的自主能力、社交能力、反应能力和行为理性等特点 ,该模型能根据企业的动态组织结构、业务流程进行动态调整 ,从而有效提高了基于此模型建立的信息系统对动态企业模型的适应能力并延长其生命期 ;然后结合信息工程论和面向对象方法提出了基于主题的 MAS模型获取方法 ,它从企业行为的功能主题出发进行分析 ,获取相应的 MAS模型 .

关键词：动态企业模型多Agent系统面向对象信息工程论 MAS模型企业行为

GPS卫星定位系统在轨道测试仪中应用的研究

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铁道学报 2004年第2期26卷 120-123页

作者：陈海大张海军朱虎何闻贾叔仕浙江大学机械与能源工程学院浙江杭州310027 浙大网新科技股份有限公司浙江杭州310012

便携式轨道测试仪是检测铁路轨道平顺性的有效手段,测速模块是其重要组成部分。现有轨道测试仪的测速方法在使用中存在定位不准等缺陷,为此研究了利用GPS全球卫星定位系统的新型轨道测试仪。本文论述了系统软硬件的总体设计及应用GPS的... 详细信息

便携式轨道测试仪是检测铁路轨道平顺性的有效手段,测速模块是其重要组成部分。现有轨道测试仪的测速方法在使用中存在定位不准等缺陷,为此研究了利用GPS全球卫星定位系统的新型轨道测试仪。本文论述了系统软硬件的总体设计及应用GPS的关键技术和实验分析。新系统可以提高轨道测试仪的故障点定位精度,更快、更准地找到故障点,提高了维修效率。

关键词： GPS 轨道测试故障点定位

Electronic structure of edge dislocation of core-doped Ti in Fe

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Progress in Natural Science:Materials International 2004年第6期 15-20页

作者： DANG Hongli 1.*,WANG Chongyu 1.2,3 and shu Xiaolin 1.1. Central Iron and Steel Research Institute,Beijing 1.0081.China 2. Department of Physics,Tsinghua University,Beijing 1.0084,China 3. International Center for Materials Physics,Academica,Shenyang 1.001.,China) Central Iron and Steel Research Institute，Beijing 1.0081.China Central Iron and Steel Research Institute，Beijing 1.0081.China Department of Physics，Tsinghua University，Beijing 1.0084 China International Center for Materials Physics，Academica，Shenyang 1.001.，China

The electronic structure of an edge dislocation doped Ti lying in the (001. plane with Burgers Vector along [1.0] direction in body-centered cubic iron is investigated using the first principles discrete variational method (DVM) based on the density-functional theory. The binding energy,impurity formation energy,interatomic energy,Mulliken orbital populations and charge density difference are presented in this paper. By calculating the binding energy of the clean dislocation system and the Ti-doped system,it is found that the binding energy of Ti-doped dislocation system is lower than that of the clean dislocation system,which implies that the Ti-doped dislocation system is more stable than the clean dislocation system. The calculated result of the impurity formation energy predicts the trapping effect of dislocation core for Ti,which shows that Ti atom prefers to occupy the place at the dislocation core. The calculated results of the interatomic energy and the difference charge density of dislocation doped Ti system indicate that the stronger bonding formed between the Ti impurity and its neighbor Fe atoms will affect the mechanical property of edge dislocation. Considering the influence of Ti on the electronic structure and the energies,we can predict that the trace Ti in transition metal Fe with dislocation defect can give a significant contribution to the solid solution hardening effects and will influence the mechanical property of materials.

关键词： edge dislocation doping effect electronic structure.