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Relationship Between Vegetation Restoration and Soil Microbial Characteristics in Degraded Karst Regions: A Case Study

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Pedosphere 2011年第1期21卷 132-138页

作者： WEI Yuan YU Li-Fei ZHANG Jin-Chi YU Yuan-Chun D. L. DEANGELIS School of Resources and Environmental Management Guizhou College of Finance and Economics Guiyang 550004 (China) College of Forestry Guizhou University Guiyang 550025 (China) College of Forest and Environment Nanjing Forestry University Nanjing 210037 (China) Department of Biology University of Maimi P. O. Box 249118 Coral Gables FL 33124 (USA)

The mechanism of vegetation restoration on degraded karst regions has been a research focus of soil science and ecology for the last *** an attempt to preferably interpret the soil microbiological characteristic variation associated with vegetation restoration and further to explore the role of soil microbiology in vegetation restoration mechanism of degraded karst regions,we measured microbial biomass C and basal respiration in soils during vegetation restoration in Zhenfeng County of southwestern Guizhou Province,*** community level physiological profiles(CLPP) of the soil microbial community to were estimated determine if vegetation changes were accompanied by changes in functioning of soil microbial *** results showed that soil microbial biomass C and microbial quotient(microbial biomass C/organic C) tended to increase with vegetation restoration,being in the order arboreal community stage > shrubby community stage > herbaceous community stage > bare land *** trend was found in the change of basal respiration(BR).The metabolic quotient(the ratio of basal respiration to microbial biomass,qCO 2) decreased with vegetation restoration,and remained at a constantly low level in the arboreal community *** of the CLPP data indicated that vegetation restoration tended to result in higher average well color development,substrate richness,and functional *** utilization of specific substrate guilds was highest in the arboreal community *** component analysis of the CLPP data further indicated that the arboreal community stage was distinctly different from the other three *** conclusion,vegetation restoration improved soil microbial biomass C,respiration,and utilization of carbon sources,and decreased qCO 2,thus creating better soil conditions,which in turn could promote the restoration of vegetation on degraded karst regions.

关键词： basal respiratory community level physiological profile functional diversity metabolic quotient microbial biomass C

Finite element simulation of stretch forging using a mesh condensation method

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science china(Technological sciences) 2010年第1期53卷 227-234页

作者： CHEN Wen & CUI ZhenShan National Die & Mold CAD Engineering Research center,Shanghai Jiao Tong university,Shanghai 20003.,china National Die & Mold CAD Engineering Research center Shanghai Jiao Tong University Shanghai China

In order to reduce the computation time of finite element simulations of stretch forging process,a mesh condensation method is presented and applied to a three-dimensional rigid-viscoplastic finite element *** this method,a conventional mesh for the whole zone of a workpiece is condensed to a computational mesh for the active deformation *** vital problems are solved,which are automatic construction of the computational mesh and treatment of interfaces between the deformation zone and the rigid *** mesh condensation method is compared with conventional finite element method by simulations of a six-bite stretch forging *** simulation results including forging load,temperature distribution and effective strain distribution are *** efficiency and accuracy of this method are verified.

关键词： mesh condensation method finite element method stretch forging incremental forging

Towards a Methodology for Formal Design and Analysis of Agent Interaction Protocols ——An Investigation in Electronic Commerce

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Wuhan university Journal of Natural sciences 2001年第Z1期6卷 126-139页

作者： Wei Jun 1,2 , Cheung Shing Chi 1, Wang Xu 1 1. Department of Computer science, Hong Kong university of science and {3., Clear Water Bay, Kowloon, Hong Kong, china 2. Institute of Software, Chinese Academy of science, Beijing 100080, Ch Department of Computer science Hong Kong University of Science and Technology Kowloon Hong Kong China Institute of Software Chinese Academy of Science Beijing China

Various extensions of UML have been developed to meet the challenges of designing modern software systems, such as agent based electronic commerce applications. Recent advances in model checking technology have led it to be introduced into the development of approaches and tools to check the correctness of electronic commerce protocols. This paper focuses on the research of a method that connects an extension of AUML to model checker SPIN/Promela for the specification and verification of agent interaction protocols (AIP) in electronic commerce. The method presented here allows us to combine the benefits of visual specification with the power of some static analysis and model checking. Some algorithms and rules are developed to permit all visual modeling constructs translated mechanically into some Promela models of AIP, as supported by the model checker SPIN. Moreover, a process is illustrated to guide the specification and verification of AIP. The method is demonstrated thoroughly using the e commerce protocol NetBill as an example.

关键词： agent UML interaction protocol software agent model checking formal specification electronic commerce protocol

REAL PIECEWISE ALGEBRAIC VARIETY

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Journal of Computational Mathematics 2003年第4期21卷 473-480页

作者： Ren-hong Wang Yi-sheng Lai (Institute of Mathematical sciences, Dalian university of technology, Dalian 116024, {3.) Institute of Mathematical sciences Dalian University of Technology Dalian 116024

We give definitions of real piecewise algebraic variety and its dimension. By using the techniques of real radical ideal, P-radical ideal, affine Hilbert polynomial, Bernstein-net form of polynomials on simplex, and decomposition of semi-algebraic set, etc., we deal with the dimension of the real piecewise algebraic variety and real Nullstellensatz in Cμ spline ring.

关键词： Dimension Real piecewise algebraic variety Cμ spline ring.

Tuning emission color of phosphor for white light-emitting diodes by tailoring Ce3. and Eu2+ concentrations in Li2MSiO4(M =Ca,Sr,Ba) host utilized with combinatorial chemistry approach

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Tuning emission color of phosphor for white light-emitting d...

Preparation of nanoparticles with an environment-friendly approach

第七届全国稀土发光材料学术研讨会

作者： Lei Chen~* Yao Zhang Anqi Luo Yang Jiang~* (School of Materials science and Engineering,hefei university of {3.,hefei 23.009,china)

Recently,the photoluminescence of Ce or Eu activated LiSrSiO phosphor has attracted much more attentions for their potential application in white light-emitting diodes(LED).The mixture of the blue emission of Ce and the yellow-green emission of Eu both from LiSrSiO host is promising to produce white light directly without by adding other ***,the luminescence of Ceand Eu strongly depend on crystal field strength for the spin-allowed and parity-allowed f-d transition. Different luminescence may be tuned up by tailoring Ce and Eu concentrations in the multi-component host of LiMSiO(M= Ca,Sr,Ba).More importantly,the phosphor of a single-phase host activated by multi-activators that were used to produce white light,either matching for near ultraviolet or blue diode chips,could simplify the process of white LEDs manufacture *** properties of emission color, luminescence efficiency,color rendering index,and thermal stability of luminescence are crucial for phosphors to be used in ***,it is very difficulty to provide a dynamic prospect between luminescence properties and multi-compositions variation by using conventional one-by-one synthesis and characterization ***,only a limited number of samples are selected to study,as can found the published ***,combinatorial chemistry approach,which utilizes parallel synthesis and high-throughput screening strategies,is facile to accomplish these full factorial *** on these considerations,the photoluminescence of LiMSiO:Ce,Eu was studied with combinatorial chemistry approach for the application of *** following figure presents the composition map and 3.5 nm excited luminescence photograph of the combinatorial library which integrates 3. *** emission spectra of samples corresponding to the second row in combinatorial library are also presented.

关键词： Light-emitting diodes(LED) Phosphor Luminescence Combinatorial chemistry approach Li2MSiO4:Ce3.,Eu2+(M=Ca,Sr,Ba)

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Journal of Environmental sciences 2009年第6期21卷 727-730页

作者： YAO Kefu,PENG Zhen,FAN Xiaolin Key Laboratory of Advanced Materials Processing technology,Ministry of Education of china,Department of Mechanical Engineering,Tsinghua university,Beijing 100084,china. Key Laboratory of Advanced Materials Processing technology Ministry of Education of China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Developing various approaches for preparing high performance materials has long been topics and tasks both for scientists and for engineers. Despite that many methods have been developed for preparing nanomaterials, developing simple and environment-friendly ways for preparing nanomaterials is very attractive. Here a simple approach of synthesizing Fe3.4 nanoparticles by arc-discharge submerging in water was reported. The results showed that by this method Fe3.4 nanoparticles can be synthesized at large scale. The as-prepared Fe3.4 nanoparticles exhibited uniform spherical shape and their diameters varied with arc-discharging parameters. The experimental results showed that the size of the synthesized Fe3.4 nanoparticles can be controlled through adjusting the processing parameters. Since no vacuum system has been used, the synthesizing process is greatly simplified. In addition, only cheap deionized water and industrial iron bar are used and no pollution or harmful byproducts are found in the synthesis process. It indicated that the present approach is a simple, low-cost and environment-friendly one for preparing nanoparticles.

关键词： nanoparticles preparation approach Fe3.4

Influence of DCM dye doping on the magnetic field dependent electroluminescence in organic light emitting diodes

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science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 24-29页

作者： CHEN Ping, LEI YanLian, LIU Rong, ZHANG QiaoMing, ZHANG Yong & XIONG ZuHong School of Physical science and technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest university, Chongqing 400715, {3. School of Physical science and technology MOE Key Laboratory on Luminescence and Real-Time Analysis Southwest University Chongqing China

The DCM dye doped organic electroluminescence devices with structure of ITO/NPB/Alq 3.: DCM/Alq 3./LiF/Al were fabricated. From 15 K to room temperature, the magnetic field dependent of electroluminescence (MEL) of devices was investigated. Our observations indicated that the MEL is composed of two effects in different regimes: a low field (0≤B≤40 mT) effect and a high field (B > 40 mT) effect. For undoped devices, the low field effect exhibits a rapid rising with the increasing field, and the high field effect shows a slow increase and gradually saturates at room temperature. For doped devices, the low field rapid increase is also present, whereas the high field effect displays a decrease with the increasing field. The larger the injection current is, the more apparent the high field decrease is. In addition, the doped device demonstrates less temperature dependence of the high field effect than undoped device, although the undoped devices also present high field decrease of electroluminescence at low temperatures (T≤150 K). Based on the energy level trapping effect due to dye doping and magnetic field modulated triplet exciton annihilation, the experimental results are carefully explained.

关键词： dye doping magnetic field dependent of electroluminescence energy level traps triplet exciton annihilation

Anisodamine Inhibits Endotoxin-induced Tissue Factor Expression in Human Endothelial Cells

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Journal of Huazhong university of science and technology(Medical sciences) 2002年第4期22卷 273-275页

作者：阮秋蓉宋建新邓仲端 DepartmentofPathology DepartmentofInfectiousDisease

By study on the effect of anisodamine on lipopolysaccharide- induced expression of tissue factor(TF) in vascular endothelial cells(EC) ,the mechanism of anisodam ine antithrom bosis,as well as in the treatm ent of bacteraemic shock was *** umbilical vein endothelial cells (HUVECs) were cultured by trypsin digestion m *** activity was measured in the lysates of HUVEC by using a single step clotting *** m RNA expression was detected by Northern *** order to evaluate a possible contribution of the nuclear factor (NF) -κB pathway on the effects observed,electrophoretic mobility shift assays(EMSA) were performed using nuclear extracts from HU VECs and NF- κB- binding *** results showed that treatment of HUVEC with L PS resulted in a significant increase in TF *** dose- dependently inhibited L PS- induced upregulation of *** effects was also confirm ed on the level of specific TF m RNA expression by Northern *** ore,EMSA showed that anisodamine com pletely abolished L PS- induced NF-κB DNA binding activity in nuclear ex- tracts from HUVECs treated with L PS together with *** results suggest thataniso- damine counteracts endothelial cell activation by inhibiting L PS- induced TF expression in these *** interference with the NF- κB pathway might- at least in part- contribute to this effect. The ability of anisodamine to counteract L PS effect on endothelial cells m ight be one underlying m echanism explaining its antithrombosis and efficacy in the treatment of bacteraemic shock.

关键词： Anisodamine endothelial cell tissue factor lipopolysaccharide shock nuclear fac- tor-κB

The Signless Laplacian Spectral Radius of Tricyclic Graphs with k Pendant Vertices

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Journal of Mathematical Research with Applications 2012年第3期32卷 281-287页

作者： Jingming ZHANG1,2,Jiming GUO 2 1.School of Mathematical sciences,university of Electronic science and {3. of china, Sichuan 61173.,P.R.china 2.College of Mathematics and Computational science,china university of Petroleum, Shandong 257061,P.R.china School of Mathematical sciences University of Electronic Science and Technology of China Sichuan 611731 College of Mathematics and Computational science China University of Petroleum Shandong 257061

In this paper,we determine the unique graph with the largest signless Laplacian spectral radius among all the tricyclic graphs with n vertices and k pendant vertices.

关键词： signless Laplacian spectral radius tricyclic graph pendant vertex.