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Topological chirality and achirality of the closed circular DNAs

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Chinese science Bulletin 1997年第20期42卷 1705-1708页

作者： QIU Wenyuan and XIN Houwen1. Department of Chemical Physics, University of science and technology of{2.,{3.,{2. 2. Department of Chemistry, Lanzhou University, Lanzhou 73.000,{2. Depaitment of Chemical Physics University of Science and Technology of China Hefei 230026 China

THE study of the relations between the topological structure and its function is one of the focus-es in modern chemistry and life science. In this note we set up a topological model to de-scribe the ccDNAs on the basis of Seifert construction in knot theory. Our model for theccDNAs helps to determine whether a structure is topologically chiral or achiral. This is one ofthe fundamental biological problems.

关键词： DNA topology knot theory topologiesl chirality topological achirality.

Electron surfing acceleration in a current sheet of flares

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science china(Physics,Mechanics & Astronomy) 2009年第11期52卷 1810-1812页

作者： WANG DeYu1 & LU QuanMing2.1 Purple Mountain Observatory, Nanjing 2.0008, china 2.School of Earth and {4. {2.s, University of {2. and technology of china, hefei 2.002., china Purple Mountain Observatory Nanjing 210008 China School of Earth and space sciences University of Science and Technology of China Hefei 230026 China

A model of electron acceleration in a current sheet of flares is studied by the analytical approximation solution and the test particle simulation. The electron can be trapped in a potential of propagating electrostatic wave. The trapped electron moving with the phase velocity v p of wave may be effectively accelerated by ev p/c × B z force along the outflow direction in the current sheet, if a criterion condition K > 0 for electron surfing acceleration is satisfied. The electron will be accelerated continuously until the electron de-trap from the wave potential at the turning point S.

关键词： electron acceleration electrostatic wave current sheet

Exotic structure of the third excited state in^(2.)Na

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Chinese science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2.3. LIANG Yujie1,2.3. DENG Fuguo1,2.3. LIU Zuhua1,4.& ZHOU Hongyu1,2.3.1. Key Laboratory of Beam technology and Material Modification of Minister of Education, Beijing Normal University, Beijing 100875, china 2. Institute of Low Energy Nuclear Physics, and Department of Material science and Engineering, Beijing Normal University, Beijing 100875, china 3. Beijing Radiation Center, Beijing 100875, china 4. china Institute of Atomic Energy, Beijing 102.13. china Key Laboratory of Beam technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China Institute of Low Energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing 100875 China Beijing Radiation Center Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficie... 详细信息

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (2.1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73. and 2.1/2.5.2. fm respectively. The P value and the contribution of the asymptotic part to the 2.1/2.are compared with those of several other low energy states in 2.Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 2.Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 2.Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

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 {2. and Engineering, University of {2. and technology of{3., hefei 2.002.,{3. 2.Department of Physics Electronic and Engineering, Chizhou University, Chizhou 2.7000,{3. 3.Department of Physics, Shanghai Jiao Tong University, Shanghai 2.003.,{3. 4.College of Optoelectronic Engineering, Changzhou Institute of technology, Changzhou 2.3.02.{3. 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

Ca^(2.) signals induced from calcium stores in pancreatic islet β cells

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Chinese science Bulletin 2000年第1期45卷 51-56页

作者： ZENG Xuhui, QU Anlian, LOU Xuelin, XU Jianhua, WANG Junjian, WU Hongxiu & ZHOU Zhuan1. Institute of Biochemistry and Biophysics, Huazhong University of science and technology, Wuhan 4.2.074. china 2. Pharmacology, Huazhong University of science and technology, Wuhan 4.2.074. china {2. School of Life sciences, University of science and technology of china,{14., china Correspondence should be addressed to Zhou Zhuan. Institute of Biochemistry and Biophysics Huazhong University of Science and Technology Wuhan China Pharmacology Huazhong University of Science and Technology Wuhan China School of Life sciences University of Science and Technology of China Hefei China

In single rat pancreatic βcells, using fura-2.microfluorometry to measure [Ca2.] response upon different stimuli, the ways of calcium regulation have been studied. When the extracellular calcium concentration was 2.5 mmol/L, either 60 mmol/L KCI, 2. mmol/L D-glucose or 0.1 mmol/L tolbutamide induced increase in [Ca2.]. Such increase in [Ca2.] was absent when the same stimuli were applied under zero extracellular calcium. These results indicate that the increase of [Ca2.] is induced by the activation of voltage-dependent calcium channels in p celis. The manifold forms of [Ca2.] change induced by glucose imply that the effects of glucose are complex. 5 mmol/L caffeine or 5 mmol/L MCh increase the [Ca2.], which is independent of the external calcium, suggesting that [Ca2.] can be regulated by Ca2. release from not only the IP3.sensitive but also the ryanodine sensitive calcium stores in p celis. The latency of Ca responses for IP3.pathway (5 s) is faster than that for ryanodine pathway (3. s), it is

关键词： pancreatic β cell [Ca2.]i calcium stores glucose fura-2.

Interfacial Microstructure and Properties of Ti(C, N)/Ni Bonded by Transient Liquid-phase Diffusion

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Journal of Wuhan University of technology(Materials science) 2009年第3期24卷 432-439页

作者：周世权熊惟皓 School of Mechanical science and Engineering Huazhong University of Science and Technology Department of Mechanical Engineering University of Waterloo School of Materials science and Engineering Huazhong University of Science and Technology

Effects of the main process parameters（temperature and time） on microstructure and properties of Ti（C, N）/Ni interface bonded by （Cu＋Nb） interlayer in a vacuum diffusion bonding device were investigated. The interfacial microstructures consisted initially of Ni3.b metallic compound and eutectic of Ni3.b ＋ CuNiss, and finally transformed to （Ti, Nb）（C, N）＋Ni3.b near Ti （C, N） and NiCuss ＋ Ni3.b near Ni when diffusion bonding temperature was 1 52.0}1 573.K. It was clear that Cu was a constituent in the transient liquid phase （TLP） into which Ni was dissolved by forming Cu-Ni transition liquid. Nb was dissolved in Cu-Ni transition liquid rapidly. Ti （C, N） conld be wetted by resultant Ni-Nb-Cu transient liquid phase which was followed by a little （Ti, Nb）（C, N） solid solution formed at interface. This increased the interface combining capability. Ultimately the interface shear strength was able to reach 140 MPa. The theoretle analysis and experimental results show that the growth of interfacial reaction layer Ni3.b accords with parabola law, and the activation energy of diffusion reaction is 115.0±0.5 kJ/mol, while the diffusion reaction speed constant is 12.53.mm/s^1/2.

关键词： vacuum diffusion bonding transient liquid phase (TLP) diffusion bonding interlayer activation energy

Modeling and verifying Web services driven by requirements:An ontology-based approach

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science in china(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3.JIN ZHi1,2.& WU Budan1,4.1. Academy of Mathematics and Systems science, Chinese Academy of sciences, Beijing 100080,{4. 2. Institute of Computing {3., Chinese Academy of sciences, Beijing 100080,{4. 3. Institute of Software, Chinese Academy of sciences, Beijing 100080,{4. 4. Graduate University of Chinese Academy of sciences, Beijing 10004.,{4. 1. Academy of Mathematics and Systems science Chinese Academy of Sciences Beijing 100080 China 3. Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. Institute of Computing technology Chinese Academy of Sciences Bejing 100080 China 4. Graduate University of Chinese Academy of sciences Beijing 100049 China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

Electrical property of 8-mol% yttria-stabilized zirconia electrolyte by spark-plasma sintering

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science china(Technological sciences) 2004年第5期47卷 569-576页

作者： JIAN Jiawen1,2. CHANG Aimin3. YANG Bangchao2.& ZHANG Yikang4.1. The School of Information science Engineering, Ningbo University, Ningbo 3.52.1, china 2. The School of Microelectronics and Solid-state Electronics, University of Electronic science and Tech-nology of china, Chengdu 610054. china 3. The Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of sciences, Urumqi 83.02., china 4. Hongtak (Chengdu) Electronic Co., Ltd, Chengdu 61004., china Correspondence should be addressed to Jian Jiawen 1. The School of Information science Engineering Ningbo University 315211 Ningbo China 2. The School of Microelectronics and Solid-state Electronics University of Electronic Science and Technology of China 610054 Chengdu China 3. The Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of Sciences 830022 Urumqi China 4. Hongtak (Chengdu) Electronic Co. Ltd 610041 Chengdu China

Spark-plasma sintering (SPS) process was used to sinter ZrO2.(8Y) powders, and a relative density of 99% has been reached at a low temperature (13.0°C) and short dwelling time (10 min) compared to the conventional sintered identical samples (14.0°C 4.h)(CS). By the X-ray diffraction (XRD) patterns, the microstructure of the SPS pellet and CS pellet are both indexed by the cubic unit cell (Fm3.). The finer crystallite size (D111) of the SPS pellet is 154.nm and D111 of the CS pellet is more than 1 μm. The AC impedance spectroscopy shows that the ionic conductivity of SPS pellet is different from that of CS pellet. The activation energy for the SPS ceramics, estimated from the slope in the range of 4.0–800°C, was 91 kJ mol?1, which is in good agreement with CS pellet (96 kJ mol?1), indicating that the conduction mechanism in SPS ceramics is similar to that in CS ceramics.

关键词： yttria-stabilized zirconia electrolyte, spark-plasma sintering, AC impedance.

Regulation of eight avr genes by hrpG and hrpX in Xanthomonas campestris pv. campestris and their role in pathogenicity

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Progress in Natural science:Materials International 2006年第12期16卷 1288-1294页

作者： XU Rongqi~ 1,3., LI Xianzhen~3. WEI Hongyu~3. JIANG Bole~2. LI Kai~3. HE Yongqiang~ 2.3., FENG Jiaxun~ 1,3.and TANG Jiliang~ 1,2.**(1. Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization 2. The Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering 3. College of Life science and technology, Guangxi University, Nanning 53.004.{14.) Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization Guangxi University Nanning 530004 China College of Life science and technology Guangxi University Nanning 530004 China The Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering Guangxi University Nanning 530004 China

Eight putative avirulence genes in Xanthomonas campestris pv. campestris (Xcc) strain 8004.were characterized by Tn5gusA5 mutagenesis and gene expression analysis. The virulence test of mutants on Chinese radish showed that all mutants in individual avr genes except avrBs2.mutant were not significantly different from the wild type in virulence. The avrBs2.mutant showed reduced virulence and bacterial growth in planta. Gene expression analysis using β-glucuronidase as reporter indicated that avrBs1.1,avrBs1,avrXccB,avrXccC,avrXccE1 were regulated by hrpG, whereas avrXccA1, avrXccA2.and avrBs2.were not. RT-PCR analysis showed that all hrpG-regulated genes except avrBs1 were also regulated by hrpX. In addition, it was demonstrated that avrBs1 was responsible for elicitation of a type III dependent hypersensitive reaction (HR) on nonhost plant pepper ECW-10R, and wild type Xcc 8004.was unable to cause HR on pepper ECW-2.R.

关键词： Xanthomonas campestris pv. campestris avirulence gene virulence expression analysis.