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CMC surfaces in the hyperbolic 3-space

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Chinese Science Bulletin 1998年第7期43卷 547-550页

作者： YU Zuhuan 1, 2.and LI Zhenqi 1, 3 1. Institute of mathematics, Fudan university, Shanghai 2.0433,{2. 2. Department of mathematics,sichuan union university, chengdu 61.064,{2. 3. Department of mathematics, Nanchang university, Nanchang 33 nstitute of Mathemalics Fudan University Shanghai China Department of mathematics Sichuan Union University Chengdu China Department of mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1.are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

Cartesian closedness of categories of completely distributive lattices

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Chinese Science Bulletin 1998年第24期43卷 2059-2063页

作者： ZHANG Dexue 1.and YANG Zhongqiang 2.1. Department of {1., sichuan {2., chengdu 61.064, china 2. Department of {1., Shaanxi Normal {2., Xi’an 71.062. china Department of mathematics Sichuan University Chengdu China Department of mathematics Shaanxi Normal University Xi’an China

The category of completely distributive lattices with Scott continuous functions is cartesian closed. Neither the category of completely distributive lattices with arbitrary union preserving mappings nor the category ... 详细信息

关键词： completely distributive lattice continuous lattice cartesian closedness.

APPLICATIONS OF THE THEORY OF CAMINA GROUPS

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Chinese Annals of mathematics,Series B 1999年第1期20卷 39-50页

作者： REN YONGCAI(Department of mathematics,{1. {2. university,chengdu 61.064,china) sichuan {1. Univ Dept Math Chengdu 610064 Peoples R China

In this papert the author first gives a conjugacy-class version of Camina hypotheses andthen applys the Camina group theory to discussing two classes of finite groups.

关键词： Camina groups Applications Characters

Diamond synthesis from a system of chromium-carbide andNi_(70)Mn_(2.)Co_5 alloy

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Chinese Science Bulletin 1998年第24期43卷 2063-2066页

作者： LI Liangbin 1. JIANG Jinchun 1. HONG Shiming 1. ZHONG Yumao 2.and ZHANG Xinyuan 2.1. Institute of Applied Physics, sichuan union university, chengdu 61.065,{2. 2. Center for Analysis and Test, sichuan union university, chengdu 61.065,{2. Institute of Applied Physics Sichuan Union University Chengdu China Center for Analysis and Test Sichuan Union University Chengdu China

In order to ascertain the mechanism of interaction between carbide and metallic catalyst and formation of diamond under high pressure and high temperature, and find a new method to synthesize diamond with special properties, it is necessary to investigate the reaction behavior of different carbides and metallic solvent_catalysts under high pressure and high temperature. A system of Cr-3C-2.powder and Ni 70Mn 2.Co 5 alloy in weight ratio of 1.6 was treated under 6 0 GPa and 1.500℃ for 2., 30 or 60 min respectively. X_ray diffraction of the samples indicated the Cr 3C 2.decomposed partially after high pressure and temperature treatment, and Cr 7C 3, Cr and diamond formed respectively. There was not any trace of graphite in the samples. The result suggested that the separated carbon atoms could form diamond directly without conversion process of graphite into diamond. The observation of SEI, WDX and EDX also showed that diamond crystals were synthesized in the system, which have perfect surfaces and shapes, with the average grain size of about 40 μm. The properties of the crystals are being investigated.

关键词： chromium_carbide high pressure synthesis diamond.

Nonequilibrium solvation theory:Comparison,modification and application

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Chinese Science Bulletin 2003年第10期48卷 965-970页

作者： FU Kexiang1.2. LI Xiangyuan1.& ZHU Quan1.1. College of Chemical Engineering, {1. university, {2. 61.065, china 2. College of Physics, {1. university, {2. 61.065, china College of Chemical Engineering Sichuan University Chengdu China College of Physics Sichuan University Chengdu China

Faults existing in the current theories of non- equilibrium solvation have been clarified in this report. Based on a novel expression of solvation free energy for nonequilibrium, generalized formulations of solvent reor- ganization energy for electron transfer and of solvation shift for spectrum have been established. Furthermore, a new form of solvent reorganization energy for electron transfer in two-sphere case, which greatly differs from the one by Mar- cus, has been deduced. A single-sphere model for solvation shift of spectrum has been put forward both by deducing the generalized formulations and by showing the correct forms of self-energy of reaction field. It has been concluded that the current theories overestimate the solvent reorganization energy and the solvation shift by a factor of about 2. By apply- ing the models established, the discrepancies between the theory and experiments before have been perfectly explained.

关键词：非平衡溶剂理论修正应用电子转移溶剂重构能量反应场溶剂交换

Population-size-dependent branching processes in Markovian random environments

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Chinese Science Bulletin 1998年第8期43卷 635-638页

作者： WANG Hanxing 1.and DAI Yonglong 2.1. Department of {1., Shanghai university, Shanghai 2.1.00,{2. 2. Department of {1., Zhongshan university, Guangzhou 51.2.5,{2. Department of mathematics Shanghai University Shanghai China Department of mathematics Zhongshan University Gunngzhou China

A branching model {Z n} n≥0is considered where the offspring distribution of the population’s evolution is not only dependent on the population size, but also controlled by a Markovian environmental process {ξ n} n≥0. For this model, asymptotic behaviour is studied such as limn→∞Z n and limn→∞Z n/m n in the case that the mean m k, θof the offspring distribution converges to m>1.as the population size k grows to ∞. In the case that {ξ n} n≥0is an irreducible positive recurrent Markov chain, certain extinction (i.e. P(Z n=0 for some n)=1. and noncertain extinction (i.e. P(Z n=0 for some n)1. are studied.

关键词： Markov chains in random environments stochastic population models branching processes.

Density functional study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine

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Science china Chemistry 2006年第4期49卷 296-307页

作者： LI Ming1. ZHENG Wenxu2.& TIAN Anmin2.1. Department of Chemistry, Southwest-china Normal university, Chongqing 40071.,{2. 2. Department of Chemistry, sichuan university, chengdu 61.064,{2. 1. Department of Chemistry Southwest-China Normal University Chongqing 400715 China 2. Department of Chemistry Sichuan University Chengdu 610064 China

The enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine is discussed by the density functional theory (DFT) method. The main intermediates and transition states for this reaction are optimized completely at the B3LYP/6-31.(d) level, and the transition states are verified by vibrational modes. As shown, the chirality-controlled steps for this re- action are the hydride transfer from borane to carbonyl carbon and oxime carbon of keto oxime ether, and the chirality for the reduced products is determined in these two reaction steps. In all examined reaction paths, the first hydride is transferred via a six-membered ring and the second hydride via a five-membered ring or a four-membered ring.

关键词： keto oxime ether, oxazaborolidine, enantioselective reduction, DFT.

Perturbations of the radical of nest algebras

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Chinese Science Bulletin 1998年第7期43卷 556-560页

作者： LU Fangyan 1.and LU Shijie 2.1. Department of {1., Suzhou university, Suzhou 2.5006,{2. 2. Department of {1., Zhejiang university, Hangzhou 31.02.,{2. Department of mathematics Suzhou University Suzhou China Department of mathematics Zhejiang University Hangzhou China

Let R N and K-N be the radical ideal and the compact operator ideal of nest algebra T(N) respectively. It is proved thatR-N+K-N=span{T∈T(N)∶TT(N)NCT}=span{T∈T(N): #σ′(ST)≤1. S∈T(N)}.

关键词： nest algebras radical perturbation.

Discovery of seismites in Upper Sinian stratiform lead-zinc deposits in Dadu River valley, sichuan,{1.: Implication for ore genesis

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Science china Earth Sciences 2006年第11期49卷 1135-1146页

作者： LIN Fangcheng1.2.& PAN Guitang2.1. Geoscience College, chengdu university of Technology, chengdu 61.059, china 2. chengdu Institute of Geology and Mineral Resources, chengdu 61.082. china 1. Geoscience College Chengdu University of Technology Chengdu 610059 China 2. {1. Institute of Geology and Mineral Resources Chengdu 610082 China

A number of lead-zinc sulphide deposits have been discovered in recent years in dolo- mitic rocks of the Upper Sinian Dengying Formation in the Dadu River valley region, sichuan Province,{1.. The lead-zinc mineralization is closely associated with a black siliceous exhalite that has been traced over 50 km of strike. This makes Dadu River valley the most extensive stratiform non-ferrous sulphide horizon having been discovered to date in{1.. In a previous study by the first author (LIN), these deposits were recognised as belonging to the broad spectrum of lead-zinc sedimentary exhala- tive (SEDEX) deposits. In this paper, seismites and seismogenetic structures occurring in close association with the Dadu River valley mineralized zone are described. The close spatial and temporal relationship between the seismites and mineralization provides strong evidence for the hypothesis that the lead-zinc SEDEX deposits formed in direct response to earthquake activities around the Sinian-Cambrian boundary. The earthquakes are postulated to be an effective dynamic mechanism for triggering the upward migration of deep circulating ore fluids along synsedimentary growth faults and their exhalation onto the sea-floor to form the extensive deposits of stratiform lead-zinc sulphide ore.

关键词： seismites, earthquake, lead-zinc deposit, hydrothermal exhalation, Upper Sinian Dengying Age.