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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. {1. of Mathematics, sichuan university,{2., china 2. {1. of Mathematics, Shaanxi Normal university, 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.

Characteristic analysis for a polynomial-like iterative equation

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Chinese Science Bulletin 1998年第3期43卷 192-196页

作者： Janusz Matkowski 1.and ZHANG Weinian 2.1. {1. of Mathematics, Technical university, 43_300 Bielsko_Biala, Poland 2. {1. of Mathematics, sichuan Union university, chengdu 61.064, china department of Mathematics Technical University Bielsko-Biala Poland department of Mathematics Sichuan Union University Chengdu China

In the light of Euler’s idea for differential equations,a polynomial_like n _order iterative equation is discussed through analyzing its characteristic polynomial. An unproved result is verified rigorously for the fi... 详细信息

关键词： iterative dynamics functional equation characteristic.

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 {1., Shanghai 2.0433, china 2. {2. of Mathematics,sichuan Union {1., chengdu 61.064, china 3. {2. of Mathematics, Nanchang {1., 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.

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., chengdu 61.065,{2. 2. College of Physics,{1., chengdu 61.065,{2. 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

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.

Numerical simulation of air-water two-phase flow over stepped spillways

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Science china(Technological Sciences) 2006年第6期49卷 674-684页

作者： CHENG Xiangju1. CHEN Yongcan1.& LUO Lin2.1. {1. of Hydraulic Engineering, Tsinghua university, Beijing 1.0084,{2. 2. State Key Laboratory of Hydraulics and Mountain River Engineering, sichuan university, chengdu 61.065,{2. department of Hydraulic Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Hydraulics Mountain River Engineering Sichuan University Chengdu 610065 China

Stepped spillways for significant energy dissipation along the chute have gained interest; popularity among researchers; dam engineers. Due to the complexity of air-water two-phase flow over stepped spillways, the finite volume computational fluid dynamics module of the FLUENT software was used to simulate the main characteristics of the flow. Adopting the RNG k- turbulence model, the mixture flow model for air-water two-phase flow was used to simulate the flow field over stepped spillway with the PISO arithmetic technique. The numerical result successfully reproduced the complex flow over a stepped spillway of an experiment case, including the interaction between entrained air bubbles; cavity recirculation in the skimming flow regime, velocity distribution; the pressure profiles on the step surface as well. The result is helpful for understanding the detailed information about energy dissipation over stepped spillways.

关键词： stepped spillway, mixture model, RNG k-εmodel, air-water two-phase flow.

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, {2. 61.065, china 2. Center for Analysis and Test, sichuan Union university, {2. 61.065, china 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.

Energy-Based Prediction of Low Cycle Fatigue Life of High-Strength Structural Steel

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Journal of Iron and Steel Research International 2012年第10期19卷 47-53页

作者： LUO Yun-rong1.2. HUANG Chong-xiang1. GUO Yi2. WANG Qing-yuan1.(1. College of Architecture and Environment, sichuan university, chengdu 61.065, {2., china 2. College of Mechanical Engineering, sichuan university of Science and Engineering, Zigong 643000, {2., china) [a] College of Architecture and Environment. sichuan university Chengdu 610065 Sichuan China [b] College of Mechanical Engineering. sichuan university of Science and Engineering Zigong 643000 Sichuan China

Energy-based models for predicting the low-cycle fatigue life of high-strength structural steels are presented. The models are based on energy dissipation during average of cycles, cycles to crack propagation and total cycles to failure. Plastic strain energy per cycle was determined and found as an important characteristic for initiation and propagation of fatigue cracks for high-strength structural steels. Fatigue strain-life curves were generated using plastic energy dissipation per cycle (loop area) and compared with the Coffin-Manson relation. Low cycle fatigue life was found similar from both methods. The material showed Masing-type behavior. The cyclic hysterisis energy per cycle was calculated from cyclic stress-strain parameters. The fracture surfaces of the fatigue samples were characterized by scanning electron microscope and the fracture mechanisms were discussed.

关键词： low cycle fatigue high-strength steel energy-based model fatigue life

Studies on the analytical potential energy function of diatomic molecular ion XY^+ using variational method

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Science china(Physics,Mechanics & Astronomy) 2004年第2期47卷 154-164页

作者： LIU Guoyue1.3, SUN Weiguo1.2.& FENG Hao1.1. Institute of Physics,{1., chengdu 61.065,{2. 2. College of Chemical Engineering,{1., chengdu 61.065,{2. 3. Mianyang Teacher抯 College, Mianyang 62.000,{2. Correspondence should be addressed to Sun Weiguo (e-mail: weiguosun@*** or guoyueliu@ ***) 1. Institute of Physics Sichuan University 610065 Chengdu China 2. Mianyang Teacher's College 621000 Mianyang China 3. College of Chemical Engineering Sichuan University 610065 Chengdu China

A new analytical potential energy function for diatomic molecular ion XY+ is proposed based on the energy consistent method (ECM). The Coulomb potential included in the new ionic potential contains multipole corrections, converges quickly and is variationally, changeable. The new potential and the ECM are applied to variationally studying the potential energies of eight electronic states of several diatomic molecular ions: the A2. state of CO+, the X2. g + state of Li 2.+ , the X2. g + state of He 2.+ , the 1.0}u state of Na 2.+ , the A2.u state of N 2.+ , the X1.+ state of KrH+, the X2.+ state of SiO+ and the A2. state of SO+ ion. The present results agree excellently with the experiment-based Rydberg-Klein-Rees (RKR) potentials, and are superior to the commonly used Huxley-Murrell-Sorbie (HMS) analytical potentials, and are better in some cases than some quantum mechanicalab initio potentials in the ionic asymptotic and dissociation regions.

关键词： potential energy, diatomic ion, electronic state, variational method.