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Mineralization episode of porphyry copper deposits in the Jinshajiang-Red River mineralization belt: Re-Os dating

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Science china Earth Sciences 2005年第2期48卷 192-198页

作者： WANG Denghong, QU Wenjun, LI Zhiwei, YIN Hanlong4 & CHEN Yuchuan institute of Mineral resources, chinese academy of Geological Sciences, beijing 100037, china National Center of Rock and Mineral Analysis, chinese academy of Geological Sciences, beijing 100037, china resource Assessment Center of Yunnan, Kunming 650011, china institute of Geology and Geophysics, chinese academy of Sciences, beijing 100101, china chinese academy of Geological Sciences, beijing 100037, china 1. institute of Mineral resources Chinese Academy of Geological Sciences 100037 Beijing China 2. National Center of Rock and Mineral Analysis Chinese Academy of Geological Sciences 100037 Beijing China 3. resource Assessment Center of Yunnan 650011 Kunming China 4. institute of Geology and Geophysics Chinese Academy of Sciences 100101 Beijing China 5. chinese academy of Geological Sciences 100037 Beijing China

Re-Os isotopic dating for the molybdenites from the porphyry copper deposits of the Jinshajiang-Red River mineralization belt in Yunnan Province yields isochron ages of 33.9±1.1 Ma for the Machangqing deposit and 34.4±0.5 Ma for the Tongchang deposit. This result shows that both the Machangqing and the Tongchang porphyry Cu-Mo deposits from two different ore-fields formed simultaneously. This new data and the published Re-Os model ages of molybdenite (35.4 Ma, 35.9 Ma, 36.2 Ma) of the Yulong porphyry copper deposit in Tibet, which is located in the same Jinshajiang-Red River mineralization belt as the Machangqing deposit and the Tongchang deposit, suggest that these three Cenozoic porphyry copper deposits in the Jinshajiang-Red River mineralization belt were contemporary for their mineralization episode. That is to say, even their present locality is far away and nearly iso-distantly distributed, these three porphyry Cu(Mo) deposits belong to the same mineralization episode at the end of Eocene.

关键词： Re-Os isotopic dating, porphyry Cu deposits, Cenozoic, mineralization episode.

Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2,3 , LI Xiao-wei 2,31. School of information Engineering, Zhejiang forestry College, Hangzhou 311300, Zhejiang, china 2. institute of Computing Technology, chinese academy of Sciences, beijing 100080, china 3. Graduate School of the chinese academy of Sciences, beijing 100039, china School of information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

Formal analysis and design of multi-party fair exchange protocols

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Science in china(Series F) 2006年第2期49卷 155-174页

作者： QING Sihan1,2,3 & LI Gaicheng1,3 1. Engineering Research Center for information Security Technology, institute of Software, chinese academy of Sciences, beijing 100080, china 2. beijing Zhongke Ansheng Corporation of information Technology, beijing 100080, china 3. Graduate School of the chinese academy of Sciences, beijing 100039, china 1. Engineering Research Center for information Security Technology Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. beijing Zhongke Ansheng Corporation of information Technology Beijing 100080 China 3. Graduate School of the chinese academy of Sciences Beijing 100039 China

Based on the origin of message items and channel combination between transacting parties, and events and relations among events, this paper presents a concise, precise, and hierarchical model for general fair exchange protocols, formally specifies various security requirements which are able to reflect inherent requirements for fair exchange protocols more rigorously, and partition these security requirements with fine granularity. This work helps analyze, debug, and design multi-party fair exchange protocols more effectively and elaborately,

关键词： fair exchange logical protocol formal model security requirement.

A mixed finite element method for the unilateral contact problem in elasticity

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Science china Mathematics 2006年第4期49卷 513-524页

作者： HUA Dongying & WANG Lieheng The First Fundamental Department, beijing information Technology institute, beijing 100101, china institute of Computational Mathematics and Scientific/Engineering Computing, academy of Mathematics and System Sciences, chinese academy of Sciences, beijing 100080, china 1. The First Fundamental Department Beijing Information Technology Institute Beijing 100101 China 2. institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China

In this paper, we provide a new mixed finite element approximation of the variational inequality resulting from the unilateral contact problem in elasticity. We use the continuous piecewise P2-P1 finite element to approximate the displacement field and the normal stress component on the contact region. Optimal convergence rates are obtained under the reasonable regularity hypotheses. Numerical example verifies our results.

关键词： unilateral contact problem, mixed finite element method.

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1,2 , XIANG Jianhai 1*, WANG Bing 1,2 , LI Fuhua 1 and TONG Wei 3(1. Experimental Marine Biology Laboratory, institute of Oceanology, chinese academy of Sciences, Qingdao 266071,china 2. Graduate School of the chinese academy of Sciences, beijing 100039, china 3. Genomics & Bioinformatics institute, chinese academy of Sciences, beijing 101300, china) chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 10446 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4% of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors

Light A physics in the lepton-specific two-Higgs doublet model

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 1981-1987页

作者： CAO JunJie 1,HENG ZhaoXia 2,3 & WAN PeiHua 1 1 College of Physics & information Engineering,Henan Normal University,Xinxiang 453007,china 2 Key Laboratory of Frontiers in Theoretical Physics,institute of Theoretical Physics,chinese academy of Sciences,beijing 100190,china 3 Kavli institute for Theoretical Physics china,chinese academy of Sciences,beijing 100190,china 1. College of Physics & information Engineering Henan Normal University Xinxiang 453007 China2. Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China3. Kavli Institute for Theoretical Physics China Chinese Academy of Sciences Beijing 100190 China

We examine various direct and indirect constraints on the lepton-specific two-Higgs doublet model and discuss its phenomenology at colliders in the allowed parameter *** constraints we consider come from the precision electroweak data,the direct search for Higgs boson,the muon anomalous magnetic moment,as well as some theoretical consistency *** find that in the allowed parameter space the CP-odd Higgs boson A is rather light (m A 30 GeV with 95% possibility),which is composed dominantly by the leptonic Higgs and decays dominantly into τ + τ;while the SM-like Higgs boson h (responsible largely for electroweak symmetry breaking) decays dominantly in the mode h → AA → 4τ with a large decay width,which will make the Higgs discovery more difficult at the ***,this scenario predicts rare Z decays Z → AAA and Z →τ + τA with their branching ratios ranging from 10-8 to 10-and 10-5 to 10-4 respectively,which may be accessible at the GigaZ option of the ILC.

关键词： Lepton-specific two-Higgs doublt model light Higgs boson A Z decays

Control of atmospheric CO_2 concentrations by 2050: A calculation on the emission rights of different countries

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Science china Earth Sciences 2009年第10期52卷 1447-1469页

作者： DING ZhongLi1, DUAN XiaoNan2, GE QuanSheng3 & ZHANG ZhiQiang4 1 institute of Geology and Geophysics, chinese academy of Sciences, beijing 100029, china 2 The General Office of chinese academy of Sciences, beijing 100864, china 3.institute of Geographic Sciences and Natural resources Research, chinese academy of Sciences, beijing 100101, china 4 The Lanzhou Branch of the National Science Library, the Scientific information Center for resources and Environment, Lanzhou 730000, china institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China The General Office of chinese academy of Sciences Beijing 100864 China institute of Geographic Sciences and Natural resources Research Chinese Academy

This paper is to provide quantitative data on some critical issues in anticipation of the forthcoming international negotiations in Denmark on the control of atmospheric CO2 concentrations. Instead of letting only a small number of countries dominate a few controversial dialogues about emissions reductions, a comprehensive global system must be established based on emissions allowances for different countries, to realize the long-term goal of controlling global atmospheric CO2 concentrations. That a system rooted in "cumulative emissions per capita," the best conception of the "common but differentiated responsibilities" principle affirmed by the Kyoto Protocol according to fundamental standards of fairness and justice, was demonstrated. Based on calculations of various countries' cumulative emissions per capita, estimates of their cumulative emissions from 1900 to 2005, and their annual emissions allowances into the future (2006―2050), a 470 ppmv atmospheric CO2 concentration target was set. According to the following four objective indicators―total emissions allowance from 1900 to 2050, actual emissions from 1900 to 2005, emissions levels in 2005, and the average growth rate of emissions from 1996 to 2005―all countries and regions whose population was more than 300000 in 2005 were divided into four main groups: countries with emissions deficits, countries and regions needing to reduce their gross emissions, countries and regions needing to reduce their emissions growth rates, and countries that can maintain the current emissions growth rates. Based on this proposal, most G8 countries by 2005 had already expended their 2050 emissions allowances. The accu-mulated financial value based on emissions has reached more than 5.5 trillion US dollars (20 dollars per ton of CO2). Even if these countries could achieve their ambitious emissions reduction targets in the future, their per capita emissions from 2006 to 2050 would still be much higher than those of developing coun

关键词： international negotiations on climate change cumulative emissions per capita emission allowance

A formal model of fair exchange protocols

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Science in china(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2,3 & LI Gaicheng1,2,3 1. Engineering Research Center for information Security Technology, institute of Software, chinese Aca- demy of Sciences, beijing 100080, china 2. beijing Zhongke Ansheng Corporation of information Technology, beijing 100080, china 3. Graduate School of the chinese academy of Sciences, beijing 100039, china 1. Engineering Research Center for information Security Technology Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. beijing Zhongke Ansheng Corporation of information Technology 100080 Beijing China 3. Graduate School of the chinese academy of Sciences 100039 Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

GIS-based analysis of forest degradations in Baihe forestry Bureau,northeast china

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Science china(Technological Sciences) 2006年第z1期49卷 167-176页

作者： ZHOU Li, DAI Limin , Guofan Shao, XU Dong, WANG Hui & BAI Jianwei institute of Applied Ecology, chinese academy of Sciences, Shenyang 110016, china Graduate University of chinese academy of Sciences, beijing 100101, china Department of forestry and Natural resources, Purdue University, West Lafayette, IN 47907, USA Department of City Development, Jinan University, Jinan 250002, china academy of forest Inventory and Planning, State forestry Administration, beijing 100714, china 1. institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. Graduate University of chinese academy of Sciences Beijing 100101 China 3. Department of forestry and Natural resources Purdue University West Lafayette IN 47907 USA 4. Department of City Development Jinan University Jinan 250002 China 5. academy of forest Inventory and Planning State Forestry Administration Beijing 100714 China

forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast china. In order to strengthen forest resource management, this paper analyzed management-induced changes in forest structure, tree species composition and forest landscape pattern from 1987 to 2000 for Baihe forestry Bureau in Jilin Province based on digitized forest parcel maps and forest survey data. The results suggested that the area of Mature, High-Stocking, and Close-Canopy forests decreased by 31.4%, 55.9% and 10.7% respectively; volume of Mixed forest, the native forest vegetation type, decreased by 17.8%;the number of patches increased tremendously but the mean patch density decreased sharply for Mature, High-Stocking, Close-Canopy, and Mixed forests. All the changes in forest structure, species composition, and landscape pattern indicated severe degradations going on with the forests in Baihe forestry Bureau. Because of the effect of degradation to forest services, restoring forest resources and protecting biodiversity has become urgently important. The strategies of sustainable forest management need to be worked out and implemented.

关键词： geographic information system, forest management, Changbai Mountains, forest change, forest decline.