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Potential energy surfaces for low-lying electronic states of SO_2

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Science china Chemistry 2006年第4期49卷 289-295页

作者： LI Anyang1, SUO Bing2. WEN Zhenyi2.& WANG Yubin2.1. Shanxi Key Laboratory of Physico-inorganic Chemistry, department of Chemistry, northwest university,{2., china 2. Institute of Modern Physics, northwest university,{2., china 1. Shanxi Key Laboratory of Physico-inorganic Chemistry Department of Chemistry Northwest University Xi’an 710069 China 2. Institute of Modern Physics Northwest University Xi’an 710069 China

The potential energy surfaces for the nine low-lying electronic states of SO2.have been constructed by using the multi-reference second order perturbation theory (MRPT2. with the basis set cc-pVTZ. The optimized geometries and the adiabatic excitation energies of these states are in good agreement with experiments and previous calculations. The crossings and avoided crossings dis- played in the potential energy surfaces are expounded.

关键词： cross of PES, MRPT2. SO2 (sulfur dioxide).

Invariant sets and solutions to the generalized thin film equation

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Science china Mathematics 2007年第6期50卷 875-886页

作者： Chang-zheng QU & Chun-rong ZHU Center for Nonlinear Studies, northwest university, xi’an 710069,{2. department of Mathematics, northwest university, xi’an 710069,{2. department of Mathematics, Anhui Normal university, Wuhu 2.1000,{2. 1. Center for Nonlinear Studies Northwest University Xi’an 710069 China 2. department of Mathematics Northwest University Xi’an 710069 China 3. department of Mathematics Anhui Normal University Wuhu 241000 China

The invariant sets and the solutions of the 1+2.dimensional generalized thin film equation are discussed. It is shown that there exists a class of solutions to the equations, which are invariant with respect to the set $$E_0 = \{ u:u_x = v_x F(u),u_y = v_y F(u)\} ,$$ where v is a smooth function of variables x, y and F is a smooth function of u. This extends the results of Galaktionov (2.01) and for the 1+1-dimensional nonlinear evolution equations.

关键词： thin film equation invariant set invariant solution rotation group scaling group 35K55 35K40 82.2.

On the Mean Value Formula of Dedekind Sums

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Acta Mathematica Sinica,English Series 1999年第2期15卷 245-254页

作者： xiali He Wenpeng Zhang, department of Mathematics, northwest university,{2., P. R. china department of Mathematics Northwest University Xi’an P. R. China

The main purpose of this paper is to use the mean value theorem of the Dirichlet L-function to study the distribution property of Dedekind sums, and to give a sharper mean value formula.

关键词： Dedekind sums Distribution of the mean value Asymptotic formula

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. ZHANG Jiao qiang 3 (1. department of Chemistry,northwest {2., xi′an 710065, china 2. department of Chemistry and chemical engineering, Baoji College of Arts and Science, Baoji 72.007, china 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

Vermiform trace fossils from the Precambrian Ruyang Group, western Henan

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Chinese Science Bulletin 1997年第3期42卷 251-254页

作者： HU Jianmin, MENG Qingren and LI Wenhou1 xi’ an College of Geology, xi’an 710054, china 2. Institute of Geophysics, Chinese Academy of Sciences, Beijing 100101, china 3 {2. of Geology, northwest university, xi’an 710069, china xi’an College of Geology Xi’an China Institute of Geophysics Chinese Academy of Sciences Beijing China department of Geology Northwest University Xi’an China

THE origin and evolution of Precambrian lives has been a long-standing controversial problem. It is now generally accepted by most paleontologists that the origin of metazoa can be traced back to more than 1000 Ma, because the Ediacara and latest pre-Ediacara fauna, such as the Huainan fauna, are featured by their diversification of forms, complicated structures

关键词： Precambrian trace fossil Ruyang Group.

PRELIMINARY GROUP CLASSIFICATION OF EQUATION v_t=f(x, v_x)v_(xx)+g(x, v_x)

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Acta Mathematica Scientia 1997年第3期17卷 255-261页

作者：屈长征 department of Mathematics Northwest University Xi'an 710069 China

Using the method of preliminary group classification introduced by Ibragimov et al[***.32.2.88(1991)], we give a classification of equations vt= f(x, vx)vxx+g(x, vx) which admitting an extension by one of the principal Lie algebra of the equation. The result of this paper is a table of nonequivalent equations possessing an additional symmetry.

关键词： SYMMETRY CLASSES COEFFICIENT

Northernmost paleo-tethyan oceanic basin in Tibet:Geo-chronological evidence from ^(40)Ar/^(39)Ar age dating of Dur'ngoi ophiolite

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Chinese Science Bulletin 2001年第14期46卷 1203-1205页

作者： CHEN Liang, SUN Yong, PEI xianzhi, GAO Ming, FENG Tao, ZHANG Zhongqing & CHEN Wen1. Laboratory of Continental Dynamics, northwest university, xi’an 710069,{2. 2. department of Geology, northwest university, xi’an, 710069,{2. 3. Institute of Geology, Chinese Academy of Geological Sciences, Beijing, 100037,{2. Laboratory of Continental Dynamics Northwest University Xi’an China department of Geology Northwest University Xi’an China Institute of Geology Chinese Academy of Geological Sciences Beijing China

Whole rock 40Ar/39Ar age dating has been conducted on a basalt sample from Dur’ngoi ophiolite, Qinghai Province, which was reported to be the northernmost pa-leo-tethyan oceanic basin in Tibet. A high temperature pla-teau age (345.3±7.9 Ma) with an isochorn age (336.6±7.1 Ma) has been obtained, representing the eruption time of oceanic crust Considering related geological settings, the new age provides constraints on the northernmost pa-leo-tethyan suture zone in Tibet and the tectonic evolution of Paleo-tethys in Northeast Tibet and adjacent areas.

关键词： Dur’ngoi ophlolite 40Ar -39Ar age Paleo-tethys.

Liquid-solid adsorption from binary component mixture

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Chinese Journal of Chemistry 1993年第5期11卷 385-394页

作者： GENG,xin-Peng department of Textile chemical {2.,northwest Textile {2. Institute,xi’an 710048GENG,xin-Du department of Chemistry,northwest university,xi’an 710069 department of Textile chemical {2. Northwest Textile Engineering Institute Xi'an 710048 department of Chemistry Northwest University Xi'an 710069

Based on five thermodynamic equilibria among the components Ⅰ,Ⅱ,and adsorbent,a stoichiometric displacement model of adsorption(SDM-A)from binary liquid mixture with complete range of concentration in liquid-solid system is proposed and tested by using data published in litera- *** two expressions of this model show the quantitative relationships between the activity of the component Ⅰ on the surface and that in the bulk solution and between its partition coefficient in two phases and its equilibrium activity in bulk solution,*** some cases,the two expressions may become two linear equations,from which the correspondingly linear slopes(*** adsorption parameters)are obtained with which the stoichiometric displacement relation and relative adsorption ability between components Ⅰ and Ⅱ can be *** effectiveness of these two expressions for different adsorption systems and the similarity and difference between SDM-A and the Freundlich Em- pirical Equation are also investigated.A rule illustrating a parallel relationship between 2./Z and the property of bulk solution is also ***,having studied the quantitative relation of the adsorption from either ideal or non-ideal liquid mixture and compaired their linear adsorption parameters,we find that SDM-A is much better than the Langmuir's.

关键词： adsorbent thermodynamic similarity partition adsorbed equilibria elucidated naked stoichiometric absolute

Discovery of bipinnatifid fronds of Protoblechnum contractum(Gu et Zhi)

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Chinese Science Bulletin 1999年第4期44卷 381-383页

作者： SUN Bainian and SHEN Guanglong department of Geology, Lanzhou university, Lanzhou 730000,{2. department of Geology, northwest university, xi’an 710069,{2. department of Geology Lanzhou University Lanzhou China department of Geology Northwest University Xi’an China

IN Permian floras of china, a dispute over the relationship among the Protoblechnum and other similar plants such as Compsopteris, Glenopteris and Supaia has been existing for a long time, and moreover it has not been completely solved up to now. Halle placed a few simple pinnate fronds from the Shihhotze Formation in the genus Protoblechnum and named them Protoblechnum Wongii Halle 70 years ago when he was studying the fossil plants from the Late Palaeozoic strata in Shanxi, china. He did not think forked or unforked fronds as an important dividing genus condition in discussing the distinction among Protoblechnum and other relative fossils. Zalessky alSO found some specimens similar to Chinese Protoblechnum while he studied the Permian fossil plants from Russia. However, he did not approve of

关键词： very over Discovery of bipinnatifid fronds of Protoblechnum contractum Gu et Zhi