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Spin Trapping of the Phosphorus-centered Radicals Generated from Hydrogen Abstraction Reaction by 2,2-Diphenyl-1-picrylhydrazyl

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Chemical Research in Chinese Universities 2000年第4期16卷 313-319页

作者： Yoshimi Sueishi and Yuko Nishihara (department of Chemistry, Faculty of science, Okayama university, 3-1-1 Tsushima Naka, Okayama 700-8530, Japan) Okayama Univ Fac Sci Dept Chem Okayama 7008530 Japan

Two kinds of the phosphorus-centered radicals produced from hydrogen atomion by 2, 2-diphenyl-1-picrylhydrazyl(DPPH were trapped by N-tert-butyl-α-phenylnitrone(PBN) and 5, 5-dimethyl-1-pyrroline N-oxide (DMPO), and investigated by means of EPR spectroscopy. The spin adducts with a characteristic hyperfine coupling constant(hfcc) caused by a phosphorus atom were observed. Based on the hfcc values caused by the phosphorus and hydrogen atoms, the con formational positions of the adducts trapped by PBN and DMPO are discussed.

关键词： EPR Spin trap Phosphorus-centered radical

s-ordering operator expansions of quantum-mechanical fundamental representations and their applications

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science China(Physics,Mechanics & Astronomy) 2011年第12期54卷 2150-2154页

作者： FAN HongYi 1,3 , XU YeJun 2 & YUAN HongChun 3,4 1 department of Materials science and Engineering, university of science and Technology of China, Hefei 230026, China 2 department of Physics Electronic and Engineering, Chizhou university, Chizhou 247000, China 3.department of Physics, Shanghai Jiao Tong university, Shanghai 200030, China 4 College of Optoelectronic Engineering, Changzhou Institute of Technology, Changzhou 213.02, China 1. department of Materials science and Engineering University of Science and Technology of China Hefei 230026 China3. Department of Physics Shanghai Jiao Tong University Shanghai 200030 China2. Department of Physics Electronic and Engineering Chizhou University Chizhou 247000 China4. College of Optoelectronic Engineering Changzhou Institute of Technology Changzhou 213002 China

We show that the quantum-mechanical fundamental representations, say, the coordinate representation, the coherent state representation, the Fan-Klauder entangled state representation can be recast into s-ordering operator expansion, which is elegant in form and has many applications in deriving new operator identities. This demonstrates that Dirac's symbolic method can be merged into Newton-Leibniz integration theory in a broad way.

关键词： s-ordering operator expansion operator identities quantum mechanical representation

Polyphyly of the fern family Tectariaceae sensu Ching:Insights from cpDNA sequence data

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science China(Life sciences) 2007年第6期50卷 789-798页

作者： LIU HongMei1,2, ZHANG XianChun1, CHEN ZhiDuan1, DONG ShiYong3 & QIU YinLong4 1 State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of sciences, Beijing 100093, China 2 Graduate university of Chinese Academy of sciences, Beijing 100039, China 3 South China Botanical Garden, Chinese Academy of sciences, Guangzhou 510650, China 4 department of Ecology and Evolutionary Biology, university of michigan, Ann Arbor, MI 48109-1048, usa State Key Laboratory of Systematic Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China Graduate university of Chinese Academy of sciences Beijing 100039 China South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China department of Ecology Evolutionary Biology University of Michigan Ann Arbor MI 48109-1048 USA

Tectariaceae are a pantropical fern family of about 20 genera, among which 8 are distributed in China. The morphological distinctiveness of the family is widely recognized, yet relatively little systematic research has been conducted on members of Tectariaceae. Phylogenetic analyses of chloroplast DNA sequence data (rbcL; atpB) from 15 species representing all 8 genera in China were carried out under parsimony criteria; Bayesian inference. The phylogenetic reconstructions indicated that the fern family Tectariaceae as traditionally circumscribed are polyphyletic. Ctenitis, Dryopsis, Lastreopsis clustered with; should be included within the newly-defined Dryopteridaceae,; Pleocnemia is also tentatively assigned to it. A narrowly monophyletic Tectariaceae is identified, which includes Ctenitopsis, Hemigramma, Pteridrys, Quercifilix,; Tectaria. In the single rbcL analysis, Arthropteris clustered with the above-mentioned monophyletic Tectariaceae. Although further investigations are still needed to identify infrafamilial relationships within the monophyletic Tectariaceae; to redefine several problematic genera, we propose a working concept here that better reflects the inferred evolutionary history of this group.

关键词： Tectariaceae, polyphyly, rbcL, atpB

Global existence of smooth solutions to two-dimensional compressible isentropic Euler equations for Chaplygin gases

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science China Mathematics 2010年第3期53卷 719-738页

作者： KONG DeXing 1 , LIU KeFeng 2 & WANG YuZhu 3, 1 department of Mathematics, Zhejiang university, Hangzhou 310027, China 2 department of Mathematics, university of California at Los Angeles, CA 90095, usa 3.department of Mathematics, Shanghai Jiao Tong university, Shanghai 200248, China 1. department of Mathematics Zhejiang University Hangzhou 310027 China2. Department of Mathematics University of California at Los Angeles Los Angeles CA 90095 USA3. Department of Mathematics Shanghai Jiao Tong University Shanghai 200248 China

In this paper we investigate the two-dimensional compressible isentropic Euler equations for Chaplygin gases. Under the assumption that the initial data is close to a constant state and the vorticity of the initial velocity vanishes, we prove the global existence of the smooth solution to the Cauchy problem for twodimensional flow of Chaplygin gases.

关键词： Chaplygin gases compressible Euler equations irrotational flow null condition Cauchy problem smooth solution

Robust observer-based control for uncertain discrete-time piecewise affine systems

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控制理论与应用（英文版） 2012年第2期10卷 236-243页

作者： Yahui GAO 1 , Zhiyuan LIU 2 , Hong CHEN 3 1.AVIC (Aviation Industry Corporation of China) China Aviation Motor Control System Institute, Wuxi Jiangsu 214063, China 2.department of Control science and Engineering, Harbin Institute of Technology, Harbin Heilongjiang 150001, China 3.department of Control science and Engineering, Jilin university, Changchun Jilin 13.025, China AVIC (Aviation Industry Corporation of China) China Aviation Motor Control System Institute Wuxi Jiangsu China department of Control science and Engineering Harbin Institute of Technology Harbin Heilongjiang China department of Control science and Engineering Jilin University Changchun Jilin China

The main contribution of this paper is to present a novel robust observer-based controller design method for discrete-time piecewise affine systems with norm-bounded uncertainties. The key ideas are to construct a piecewise quadratic Lyapunov function to guarantee the stability of the closed-loop systems, approximate polytopic operating regions by ellipsoids, and use the singular value decomposition technique to treat the constraint of matrix equality. It is shown that the suggested control method can be formulated as linear matrix inequalities that are numerically feasible with commer- cially available software. A numerical example is also given to verify the proposed approach.

关键词： Piecewise affine systems Robust control Observer Linear matrix inequality

A HYPERBOLIC SYSTEM OF CONSERVATION LAWS FOR FLUID FLOWS THROUGH COMPLIANT AXISYMMETRIC VESSELS

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Acta Mathematica Scientia 2010年第2期30卷 391-427页

作者： Gui-Qiang G.Chen School of Mathematical sciences,Fudan university,Shanghai 200433,China Mathematical Institute,university of Oxford,24-29 St Giles,Oxford,OX1 3LB,UK department of Mathematics,Northwestern university,Evanston,IL 60208-2730,usa Weihua Ruan department of Mathematics,Computer science and Statistics,Purdue university Calumet,Hammond,IN 46323-2094,usa [a] School of Mathematical sciences Fudan University Shanghai 200433 China [b] Mathematical Institute University of Oxford 24-29 St Giles Oxford OX1 3LB UK [c] Department of Mathematics Northwestern University Evanston IL 60208-2730 USA [d] Department of Mathematics Computer Science Statistics Purdue University Calumet Hammond IN 46323-2094 USA

We are concerned with the derivation and analysis of one-dimensional hyperbolic systems of conservation laws modelling fluid flows such as the blood flow through compliant axisyminetric vessels. Early models derived are nonconservative and/or nonho- mogeneous with measure source terms, which are endowed with infinitely many Riemann solutions for some Riemann data. In this paper, we derive a one-dimensional hyperbolic system that is conservative and homogeneous. Moreover, there exists a unique global Riemann solution for the Riemann problem for two vessels with arbitrarily large Riemann data, under a natural stability entropy criterion. The Riemann solutions may consist of four waves for some cases. The system can also be written as a 3 × 3 system for which strict hyperbolicity fails and the standing waves can be regarded as the contact discontinuities corresponding to the second family with zero eigenvalue.

关键词： conservation laws hyperbolic system fluid flow blood flow vessel hyper-bolicity Riemann problem Riemann solution wave curve shock wave rarefaction wave standing wave stability

Observations on the Efficacy of Various Forms of Selenium for Livestock: A Review

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Biomedical and Environmental sciences 1997年第2期10卷 280-291页

作者： J. E. OLDFIELD (department or Animal science, Oregon State university,Corvallis, OR 97331, usa) department of Animal science Oregon State University Corvallis 97331 USA.

Since 1957, selenium has found extensive use in livestock production to maintain an adequate selenium status in animals in areas of soil and feed/forage deficiency. Selenium may be given directly to livestock, or applied as a fertilizer amendment to increase selenium content of their feeds. This paper addresses the area of direct supplementation, which includes oral and parenteral supplementation, and with ruminant animals the use of slow-release boluses. Various chemical forms of selenium have been examined as supplemental sources, with sodium selenite being the earliest compound of choice. Comnbination of selenium supplementation with other livestock managernent practices led to use of selenium dioxide, which avoided solubility problems with selenite but produced effective responses. Barium salts have been used with some success as supplemental selenium sources. Experience with ruminal boluses has shown that high pressure pelleting of increased grain size selenium, in hollow pellets, has prolonged their useful life. Attention has been paid recently to residual selenium returned to the soil from livestock supplementation practices and the resulting opinion is that currently approved practices are acceptable from the point of view of environmental quality

关键词： A Review Observations on the Efficacy of Various Forms of Selenium for Livestock

Some Physical Properties of CuTlSe Alloy

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Journal of Materials science & Technology 2001年第2期17卷 229-232页

作者： A.Abdel All Physics department, Faculty of science , Helwan university, Cairo, Egypt K.A.Sharaf Physics department, Faculty of science, Al-Azhar university for Girls, Cairo, Egypt A.Elshafie Physics department, Faculty of science, Menoufia university, She Helwan Univ Fac Sci Dept Phys Cairo Egypt Al Azhar Univ Girls Dept Phys Fac Sci Cairo Egypt Menoufia Univ Fac Sci Dept Phys Shibin Al Kawm Egypt

The structure and optical properties of Cu0.1Tl2Se3 alloy was studied. X-ray analysis showed that the polycrystalline powder consists of a mixture of two phases Cu3jTlSe2 (monoclinic) and TISe (tetragonal). Chalcopyrite phase CuTISe2 can be obtained by annealing the powder at 250'C for 1 h. Thin film with a monoclinic phase of Cu3TlSe2 was obtained for the thick film (0.7 um). The optical parameters a, n, k, e' and e' and the energy gap were calculated. The thermoelectric power measurements showed that S has a positive polarity over the whole range of temperature.

关键词： Cu Some Physical Properties of CuTlSe Alloy

Effect of Fe metal on the growth of silicon oxide nanowires

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 317-321页

作者： Wei-long Liu1), Shu-huei Hsieh1), Ching He Chen2), and Wen-jauh Chen3) 1) department of Materials science and Engineering, Formosa university, Yunlin 632, China Taipei 2) department of Materials Engineering, Pingtung university of science and Technology, Pingtung 912, China Taipei 3) Graduate School of Materials science, Yunlin university of science and Technology, Yunlin 632, China Taipei [a]department of Materials science and Engineering Formosa University Yunlin 632 China Taipei [b]Department of Materials Engineering Pingtung University of Science and Technology Pingtung 912 China Taipei [c]Graduate School of Materials Science Yunlin University of Science and Technology Yunlin 632 China Taipei

Silicon oxide (SiOx) nanowires are generally grown on Si substrate under the catalysis of Au in N2 atmosphere at elevated temperatures. Because the price of Au metal is quite high, Fe metal is then used to replace a part of Au for catalyzing the growth of SiOx nanowires. The results show that the Fe film can be used as the diffusion barrier of Au. SiOx nanowires are grown on Au/Fe/Si substrate at 1030°C. Under the catalysis of Fe/Au, the efficiency for the growth of SiOx nanowires is promoted.

关键词： silicon oxide nanowires Au catalyst Fe substitution Si substrate