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Contemporary International Relations 2002年第12期12卷 41-56页

作者： zhang Yanyu wang Wenfeng the Division for American Studies in China Institute of Contemporary International Relations.

The first mid-term election of the U. S. in the new century took place on November 5, 2002. One third of the senators from the 107th Congress (34 out of 100), all representatives (435), 36 state governors, and numerous local officials and legislators were to be elected or reelected. The resounding victory of the GOP in the congressional elections and the fact that the Democrats only got three more.

关键词： Mid-Term Election zhang Yanyu and wang Wenfeng are both assistant research professors at the Division for American Studies in China Institute of Contemporary International Relations On the 2002 U zhang wang

The largest known odonate in China: Hsiufua chaoi zhang et wang, gen. et sp. nov. from the Middle Jurassic of Inner Mongolia

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Chinese Science Bulletin 2013年第14期58卷 1579-1584页

作者： zhang HaiChun ZHENG DaRan wang Bo FANG Yan JARZEMBOWSKI Edmund A State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of Sciences Graduate University of the Chinese Academy of Sciences

A new genus and species, Hsiufua chaoi zhang et wang, is established based on a forewing from the Middle Jurassic Haifanggou Formation in Inner Mongolia, China and attributed to Campterophlebiidae, Isophlebioidea, Odonata. It is the largest odonate known in China and the fourth in the world in terms of forewing length. The maximum size (based on forewing length) of Odonata is smaller in the Permian than in the Mesozoic which is probably due to competition for prey between Odonata and Protodonata in the Permian. The reason that the maximum size of Jurassic odonates is larger than that of their extant relatives is most probably less competition and lower predation pressure from contemporary aerial vertebrates.

关键词：内蒙古中国中侏罗世 SP 中侏罗统脊椎动物最大尺寸二叠纪

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建设健康社会的催化剂:健康社会工作者与全科医生在基层的合作

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中国全科医学 2025年第4期28卷 516-520页

作者：李奕桦赵艾杨曾飞方雪张旺王欣武汉大学中南医院创伤与显微骨科湖北省武汉市430071 巴东县人民医院骨科湖北省恩施土家族苗族自治州444300

以“健康中国”战略为导向,从优势互补专业知识、共同连接医院社区、拓展研究社会健康三个方面去探讨健康社会工作者与全科医生在基层卫生环境中的合作价值,尤其在完善公共卫生应急体系和构建医联体上,健康社会工作者与全科医生的合作... 详细信息

以“健康中国”战略为导向,从优势互补专业知识、共同连接医院社区、拓展研究社会健康三个方面去探讨健康社会工作者与全科医生在基层卫生环境中的合作价值,尤其在完善公共卫生应急体系和构建医联体上,健康社会工作者与全科医生的合作可以发挥必不可少的作用,能有效推动健康社会的建设进程。同时文章也指明了目前健康社会工作面临的主要挑战,并提出相应的对策。

关键词：健康社会健康社会工作者全科医生基层卫生公共卫生应急医联体

A POSTERIORI ESTIMATOR OF NONCONFORMING FINITE ELEMENT METHOD FOR FOURTH ORDER ELLIPTIC PERTURBATION PROBLEMS

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Journal of Computational Mathematics 2008年第4期26卷 554-577页

作者： Shuo zhang Ming wang LMAM and School of Mathematical Sciences Peking University Beijing 100871 China

In this paper, we consider the nonconforming finite element approximations of fourth order elliptic perturbation problems in two dimensions. We present an a posteriori error estimator under certain conditions, and give an h-version adaptive algorithm based on the error estimation. The local behavior of the estimator is analyzed as well. This estimator works for several nonconforming methods, such as the modified Morley method and the modified Zienkiewicz method, and under some assumptions, it is an optimal one. Numerical examples are reported, with a linear stationary Cahn-HiUiard-type equation as a model problem.

关键词： Fourth order elliptic perturbation problems Nonconforming finite elementmethod A posteriori error estimator Adaptive algorithm Local behavior.

Investigation of MXenes as oxygen reduction electrocatalyst for selective H_(2)O_(2) generation

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Nano Research 2022年第5期15卷 3927-3932页

作者： Xiao Huang Min Song Jian zhang Jingjing zhang Wei Liu Chang zhang wang zhang Deli wang Key Laboratory of Material Chemistry for Energy Conversion and Storage(Huazhong University of Science and Technology) Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518055China

Two-electron oxygen reduction reaction(ORR)catalysts are essential for the electrosynthesis of hydrogen peroxide(H_(2)O_(2)).MXenes,a rising family of two-dimensional(2D)transition metal carbides,have been extensively studied for energy storage and(photo)electrocatalysis due to their rich chemical compositions and tunable electronic *** this work,three representative MXenes of Ti_(3)C_(2)T_(x),V_(2)CTX,and Nb_(2)CTX were selected for H_(2)O_(2)electrosynthesis and we found that MXenes are inherent two-electron ORR catalysts with high H_(2)O_(2)*** addition,this work critically evaluates their electrocatalytic activity and ***,Nb_(2)CT_(x)catalyst maintains better electrocatalytic activity and higher stability for a long time test,although the stability of Ti_(3)C_(2)T_(x)and V_(2)CT_(x)catalysts is poor owing to the metal dissolution property of Ti and V in alkaline ***,the assembled device based on Nb2CTx catalyst presents a high H2O2 production and a rapid organic dye decoloration ability.

关键词： electrosynthesis hydrogen peroxide oxygen reduction reaction MXenes

High‑Efciency g‑C_(3)N_(4) Based Photocatalysts for CO_(2) Reduction:Modifcation Methods

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Advanced Fiber Materials 2022年第3期4卷 342-360页

作者： Qingtong wang Zixi Fang wang zhang Di zhang State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong University800#Dongchuan Rd.Shanghai 200240People’s Republic of China

Photocatalysis is an efective means to solve the greenhouse efect caused by the large amount of carbon dioxide(CO_(2))emissions from fossil fuel *** carbon nitride(g-C_(3)N_(4))has the advantages of suitable band gap,easy preparation,low price,and good stability,making it a promising semiconductor ***,bulk g-C3N4 also has disadvantages such as low gas adsorption,low photocatalytic efciency,narrow spectral response,and easy recombination of electron–hole *** modifcation method based on g-C_(3)N_(4) photocatalyst helps to improve the above-mentioned *** review summarizes the research progress in recent years from four aspects:morphology adjustment,co-catalysts,heterostructures and *** aspect includes the pros and cons of diferent improvement methods,the comparison of theoretical calculations and experimental results,the application of diferent characterization methods,and the detailed listing of product yield and *** to this,there was an explanation of the basic theory of semiconductor photocatalytic CO_(2) ***,the future challenges and development prospects are also briefy prospected.

关键词： g-C_(3)N_(4) Photocatalytic CO_(2)reduction Morphology adjustment Co-catalysts Heterostructures Doping

A Large-update Interior-point Algorithm for Convex Quadratic Semi-definite Optimization Based on a New Kernel Function

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Acta Mathematica Sinica,English Series 2012年第11期28卷 2313-2328页

作者： Ming wang zhang College of Science China Three Gorges University

In this paper, we present a large-update interior-point algorithm for convex quadratic semi-definite optimization based on a new kernel function. The proposed function is strongly convex. It is not self-regular function and also the usual logarithmic function. The goal of this paper is to investigate such a kernel function and show that the algorithm has favorable complexity bound in terms of the elegant analytic properties of the kernel function. The complexity bound is shown to be O（√n（logn）2 log e/n）. This bound is better than that by the classical primal-dual interior-point methods based on logarithmic barrier function and in optimization fields. Some computational results recent kernel functions introduced by some authors have been provided.

关键词： Convex quadratic semi-definite optimization kernel function interior-point algorithm^large-update method complexity

Effect of nano-oxide layers on the magnetoresistance of ultrathin permalloy films

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Rare Metals 2009年第6期28卷 624-628页

作者： wang Le zhang Jinzhong wang Lijin Department of Materials Physics and Chemistry University of Science and Technology Beijing Beijing 100083 China

Ta/NiFe/Ta ultrathin films with and without nano-oxide layers （NOLs） were prepared by magnetron sputtering followed by a vacuum annealing process. The influence of NOLs on the magnetoresistance （MR） ratio of ultrathin permalloy films was studied. The results show that the influence of grain size and textures on the MR ratio becomes weak when the thickness of the NiFe layer is below 15 nm. A higher MR ratio was observed for the thinner （〈 15 nm） NiFe film with NOLs. The MR ratio of a 10 nm NiFe film can be remarkably enhanced by NOLs. The enhanced MR ratio for these ultrathin films can be attributed to the enhanced specular reflection of conduction electrons.

关键词： material surface and interface anisotropic magnetoresistance magnetron sputtering nano oxide layer NiFe

Solvent extraction of vanadium from sulfuric acid solution

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Rare Metals 2009年第3期28卷 209-211页

作者： wang Mingyu zhang Guiqing wang Xuewen zhang Jialiang School of Metallurgical Science and Engineering Central South University Changsha 410083 China

The behaviour of vanadium（V） extracted from sulfuric acid solution was investigated using Cyanex 923 as an extractant. The effects of the concentration of Cyanex 923 and the pH of the solution were studied. The extraction of vanadium（V） increases with the increase of Cyanex 923 concentration and shaking time. Cyanex 923 can extract vanadium（V） from sulfuric acid solution at low pH conditions, and the best pH conditions for extraction of vanadium（V） are at pH 1.0-2.0. The species extracted into the organic phase is VO2HSO4 with one molecule of Cyanex 923. Equilibrium studies were used to assess the extraction efficiency of vanadium（V） recovery from the sulfuric acid solution.

关键词： solvent extraction vanadium(V) Cyanex 923 sulfuric acid solution

Research on physical layer traffic management schemes in serial RapidIO interconnect

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 64-69页

作者： zhang Yong wang Yong zhang Ping Wireless Technology Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications 13eijing 100876 China

A traffic management scheme in serial RapidlO （SR10） interconnect is proposed to deal with the performance degradation caused by noise and electromagnetic interference （EMI）, which is generated by hardly avoidable errors of hardware implementation and tough working environment. The main idea of this scheme includes adaptive speed transition and freeze-acknowledgement （freeze-ACK）. Adaptive speed transition can improve throughput and reduce delay in high bit error rate （BER） environment. Simultaneously, freeze-ACK is adopted to conquer frequent usage of feedback channel. Simulation shows that the scheme of combining adaptive speed transition with freeze-ACK offers great performance improvement in SRIO network.

关键词： serial RapidIO traffc management physical layer traffic management adaptive speed transition frecze-ACK