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Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2,3. ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2 & ZHENG Du1 1. Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china 2. Graduate school of the chinese academy of sciences, Beijing 10003., china 3. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716, china 4. The Ministry of Science and Technology, P. C. china, Beijing 100862, china 5. Chengdu Institute of Biology, chinese academy of sciences, Chengdu 610041, china 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate school of the chinese academy of {3. 100039 Beijing China 3. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and Technology P. C. China 100862 Beijing China 5. Chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2000 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2000, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43.. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2000, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

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Preparation of Pt/K_2La_2Ti_3._(10) and its photo-catalytic activity for hydrogen evolution from methanol water solution

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Science china Chemistry 2006年第2期49卷 162-168页

作者： CUI Wenquan1,3. LIU Li2, FENG Liangrong1, XU Chenghua1, LI Zijian1, Lü Shaojie1 & QIU Fali1 1. Chengdu Institute of Organic Chemistry, chinese academy of sciences, Chengdu 610041,{3. 2. Chemistry Department, Sichuan University of Science & Engineering, Zigong 643.3.,{3. 3. Graduate school of the chinese academy of sciences, Beijing 10003.,{3. Correspondence should be addressed to Qiu Fali 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China 3. Graduate school of the chinese academy of {3. Beijing 100039 China 2. Chemistry Department Sichuan University of Science & Engineering Zigong 643033 China

A layered perovskite-type oxide K2La2Ti3.10 was prepared with high-temperature solid-state reaction, and characterized with X-ray diffraction (XRD) and ultraviolet-visible diffuse re-flectance spectroscopy (UV-Vis DRS). Platinum was loaded onto K2La2Ti3.10 as a co-catalyst with different methods. The dispersion of platinum on K2La2Ti3.10 was determined with HOT method. The photocatalytic activity of Pt/K2La2Ti3.10 was studied. This catalyst showed much higher activity in hydrogen evolution reaction than Ni/K2La2Ti3.10. The effects of different amounts of loaded platinum and several preparation methods were evaluated. The best achieved hydrogen evolution rate was 23..88 μmol·h?1 by Pt(2%)/K2La2Ti3.10. A possible band structure and mechanism were discussed based on the results.

关键词： photocatalysis hydrogen platinum K_2La_2Ti_3._(10) support

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A new DNA algorithm to solve graph coloring problem

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Progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2, Meng Ya3.and Meng Dazhi2(1. National Laboratory of Pattern Recognition,Institute of Automation, chinese academy of sciences, Beijing 100080,{3. 2. College of Applied sciences, Beijing University of Technology, Beijing 100022,{3. 3. school of Science, Beijing Institute of Technology, Beijing 100081,{3.) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China College of Applied sciences Beijing University of Technology Beijing 100022 China school of Science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

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Investigation into the rotational bands of ^(185)Pt with the particle-rotor model

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 114-118页

作者： LI GuangShun1,2, ZHOU XiaoHong1,2, ZHANG ShuangQuan3. ZHANG YuHu1 & MENG Jie3.1 Institute of Modern Physics, chinese academy of sciences, Lanzhou 73.000,{3. 2 Graduate University of chinese academy of sciences, Beijing 100049,{3. 3.school of Physics and SK Laboratory of Nuclear Physics & Technology, Peking University, Beijing 100871,{3. 1. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. Graduate University of chinese academy of sciences Beijing 100049 China 3. school of Physics and SK Laboratory of Nuclear Physics & Technology Peking University Beijing 100871 China

Theoretical calculations have been performed for the ν9/2+[624](i13.2) and ν7/2-[503.(f7/2) bands of 185Pt in the framework of particle-rotor model. The band properties of signature splitting and configuration mixing have been analyzed. The level energy and signature splitting before the band crossing can be well interpreted by introducing triaxiality. The positive-parity yrast band is pro posed to be dominated by the ν9/2+[624](i13.2) component, while the negative-parity band shows strong mixing of ν7/2-[503.(f7/2) and ν9/2-[505](h9/2) configurations.

关键词： High-spin states particle-rotor model signature splitting configuration mixing

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Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System

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Wuhan University Journal of Natural sciences 2005年第4期10卷 779-784页

作者： ZHANG Ren-jun 1,2 1. Institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, Sichuan,{3. 2. Graduated school of the chinese academy of sciences, Beijing 10003.,{3. chinese academy of sciences Institute of Mountain Hazards and Environment Chengdu Sichuan China (GRID:grid.9227.e) (ISNI:***) Graduated school of the chinese academy of {3. Beijing China (GRID:grid.9227.e) (ISNI:***)

Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts.

关键词： tourist resort carrying capacity TSBS GIS Multi-Agent simulator

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The effects of shock wave and quasi-traveling wave in the mechanical impact test

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Science china(Technological sciences) 2010年第9期53卷 2535-2541页

作者： WU Mei1,5,SUN ZhongFeng2,ZHANG LuMei3.CHEN Yong1 & JI LinHong4 1 Institute of High Energy Physics,chinese academy of sciences,Beijing {3.,china 2 school of Mathematical sciences,Peking University,Beijing 100871,china 3.High school of Central University for Nationalities,Beijing 100081,china 4 Institute of Mechanical Design,Department of Precision Instruments and Mechanology,Tsinghua University,Beijing 100084,china 5 academy of Opto-electronics,chinese academy of sciences,Beijing 100190,china 1. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China5. Academy of Opto-electronics Chinese Academy of Sciences Beijing 100190 China2. School of Mathematical Sciences Peking University Beijing 100871 China3. High School of Central University for Nationalities Beijing 100081 China4. Institute of Mechanical Design Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

It is well-known that the numerical value is always larger than the measured value,amounting to many times,if we calculate the stress of the specimen in the impulse test using the NASTRAN and ANSYS (N-A) *** believe that the impact induces shock wave or quasi-traveling wave in the specimen,which can qualitatively explain the discrepancy of the two *** order to verify it,the Lax-Friedrichs (L-F) scheme is taken to simulate the transmission of shock wave and quasi-traveling wave in *** results show that the action area of the stress wave is small and the action time is very short,so the resulting stress and actual work are not *** addition,the distribution of the impact values obtained by the numerical simulation is in accordance with the trend of the measured impact values.

关键词： aerospace environment test shock wave quasi-traveling wave

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Parentage determination of an isolated Yangtze finless porpoise population Neophocaena phocaenoides asiaeorientalis in the Yangtze Tian-e-Zhou Baiji National Natural Reserve based on molecular data

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Progress in Natural Science:Materials International 2005年第2期15卷 54-61页

作者： XIA Junhong 1,2, ZHENG Jinsong 1,2, XU Limei 1,2 and WANG Ding1*(1. Institute of Hydrobiology, chinese academy of sciences, Wuhan 43.072,{3. 2. Graduate school of the chinese academy of sciences, Beijing 10003.,{3.) Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. Graduate school of the chinese academy of {3. Beijing 100039 China

Reproductive behaviors are poorly known for the Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. In this study, the parentage of an isolated Yangtze finless porpoise population inhabiting the Yangtze Tian-e-Zhou Baiji National Natural Reserve is determined by analysis of microsatellite loci and mitochondrial DNA (mtDNA) control region sequences, and the porpoise's reproductive behaviors are studied. Overall 4 full parentage assignments and additional 3.single parentage assignments were determined for the population of 23.individuals. The analysis shows that their estimated reproductive cycle is shorter than that reported previously and there probably exists an overlapping between gestation and lactation period. The study also shows that the female does not show fidelity to a particular male for breeding and vice versa, the oldest males did not monopolize mating and the dominance rank could not be so strict for the porpoise society. Moreover, the porpoise's mating pattern and relatedness among candidate parents are discussed here. These results provide important information for making guidelines of management and conservation for this protected population.

关键词： Yangtze finless porpoise isolated population reproductive behavior parentage

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Experimental and discrete element numerical analysis of side slope instability induced by fissure water underlying impervious bed

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Science china(Technological sciences) 2005年第z1期48卷 65-80页

作者： LIU Bingshan1, LI Shihai1, ZHANG Lei1,2 & WANG Jianguo3.. Institute of Mechanics, chinese academy of sciences, Beijing 100080,{3. 2. Graduate school, chinese academy of sciences, Beijing 100060,{3. 3. Tropical Marine Science Institute, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260 chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ Singapore Trop Marine Sci Inst Singapore 119260 Singapore

When the sliding mass contains impervious bed, rainfall can infiltrate into mountain via crevices and form higher artesian aquifer at impervious bed inferior. This will decrease slip resistance and increase sliding forces of the sliding mass, thus lowering the safety factor, and inducing landslide disasters. In this paper, a landslide experimental apparatus is designed for experimental studies on the mechanism of this type of landslides. Meanwhile, the non-dimensional parameters in the model experiment are taken into account using dimensional analysis. The experimental results show that (1) the ratio of the cleft water pressure to the overlying pressure is a crucial parameter affecting the stability of the slope; (2) when the shut-in pressure reaches 80% of the normal component of the pressure on the slip surface made up of rock and soil, landslide will occur; (3. the whole slope will start to slide when the shut-in pressure is equal to the normal component of the pressure formed by the overlying rock and soil on the upper 3.% area. In this article, a discrete element method simulation is used to investigate the influence of cleft water pressure and shearing strength on the landslide stability. It can be concluded that the critical value of Ccr, ?cr, which determines the slide mass stability, increases with the increase of the water pressure; if the water pressure reaches a high level, the stability of the slide mass depends mainly on C, while the influence of ? becomes smaller than C.

关键词： impervious bed, rainfall infiltration, pore water pressure, landslide experiment, displacement monitor, discrete element method.

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Association between Alcohol, Smoking and HLA-DQA1*0201 Genotype in Psoriasis

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 597-602页

作者： Guang-Yong ZHENG1,2#, Sheng-Cai WEI3., Tie-Liu SHI1, and Yi-Xue LI1* 1Bioinformatics Center, Shanghai Institutes for Biological sciences, chinese academy of sciences, Graduate school of the chinese academy of sciences, Shanghai 20003., china Research Center for Proteome Analysis, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, chinese academy of sciences, Graduate school of the chinese academy of sciences, Shanghai 20003., china 3.uangzhou Institute of Dermatology, Guangzhou 510095, china Bioinformatics Center Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences

Psoriasis is a chronic skin disease triggered by genetic, environment or other risk factors such as infection, drugs, stress, moisture, alcohol, and smoking. A major psoriasis susceptibility locus at 6p21.3. has been identified. Further studies found that HLA-DQA1*0201 allele was associated with psoriasis. However, there were few data exploring an association between the environmental factors and susceptibility genes. In this study, the samples of 189 patients with psoriasis and 3.3.healthy controls were collected with their consent and were carried on analysis through polymerase chain reaction sequence-specific primer (PCR- SSP) method. The proportion of male psoriasis patients engaging in the smoking and alcohol was much higher than that of the control group (P201 allele was present at significantly higher frequency in the patients with psoriasis (OR=4.25, P201 in male patients with psoriasis (OR>6.91, P<1.0×10–4).

关键词： psoriasis HLA-DQA1*0201 allele smoking alcohol association

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Leakproof secret sharing protocols with applications to group identification scheme

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Science china(Information sciences) 2012年第5期55卷 1172-1185页

作者： TANG ChunMing 1,2 & GAO ShuHong 3.1 school of Mathematics and Information Science,Guangzhou University,Guangzhou 510006,china 2 State Key Laboratory of Information Security,Institute of Software Science,chinese {3. of sciences,Beijing 100049,china 3.Department of Mathematical sciences,Clemson University,SC 2963.,USA 1. school of Mathematics and Information Science Guangzhou University Guangzhou 510006 China2. State Key Laboratory of Information Security Institute of Software Science Chinese Academy of Sciences Beijing 100049 China3. Department of Mathematical Sciences Clemson University Clemson SC 29634 USA

In a traditional (t,n)-threshold secret sharing scheme,t or more honest participants can reconstruct the secret *** the reconstruction process,the individual shares and the secret key K are revealed,hence K is shared once *** this paper,we firstly give the definition of leakproof secret sharing scheme which is composed of a distribution protocol and a proof protocol,then propose two leakproof secret sharing protocols,a computationally secure protocol and an information-theoretically secure *** our protocols,t or more participants can jointly prove that they hold the secret K by using a multi-prover zero-knowledge argument of *** a result,the secret K will be shared for as many times as ***,each participant can detect the dealer in the distribution protocol from cheating,and any verifier can prevent non-qualified set of participants in proof protocol from *** an example of the practical impact of our work we use our techniques to construct group identification schemes with zero-knowledge.

关键词： secret sharing leakproof secret sharing multi-prover zero-knowledge argument proof of knowl-edge group identification scheme

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