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Theoretical studies of rovibrational spectrum and potential energy function for Ar-N_2 complex

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Chinese Science Bulletin 1997年第1期42卷 43-46页

作者： YAN Guosen, XIE Junkai and XIE DaiqianDepartment of Chemistry, sichuan University, chengdu 610064, china Department of Chemistry Sichuan University Chengdu China

THE Ar-N2 complex plays an important role in atmosphere chemistry. Recently, the potential energy functions （PEF） CPV, BTT, MMSV, M3.V, MMSV’ have been determined by comparing the relevant experimental information, such as the molecular beam scattering measurements, virial coefficient data, bulk transport and relaxation phenomena, pressure-broadening and shift of spectroscopic infrared and Raman lines. The pure rotational spectrum of the Ar-14N2, Ar-15N2, and Ar-14N 15N isotopomers have been measured by Jager

关键词： potential energy function van der Waals vibrational states intensity and isotope effects.

Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 13.Cs technique

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Chinese Science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of Environmental Change and Natural Disaster, the Ministry of Education of china, Beijing Normal University, Beijing 100875, china 2. Institute of Desert Research, Chinese Academy of Sciences, Lanzhou 73.000, china 3. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, {3. 610041, china 4. Department of Physics, sichuan Union University, {3. 610041, china Key Laboratory of Environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China Institute of Desert Research Chinese Academy of Sciences Lanzhou China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-13. (13.Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 13.Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 13.Cs reference inventories of 982.11 and 2 3.6.04 Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 13.Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3. experienced the alternation of erosion and deposition,while the grasslands (S4, S6 and S7) and dry farmlands (S5) suffered erosion only. By using 13.Csmodel, the average wind erosion rates for shrub coppice

关键词： 13.Cs technique Qinghai-Tibetan Plateau wind erosion.

SOLUTION CRYSTALLIZATION OF METALLOCENE SHORT CHAIN BRANCHED POLYETHYLENE:MORPHOLOGY AND MECHANISM

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Chinese Journal of Polymer Science 2000年第1期18卷 45-49页

作者： Qiang Fu Rong-ni Du Fang-Chyou Chiu Department of Polymer Science & Materials, sichuan University, chengdu, sichuan 610065, {3. Department of Chemical Engineering, Chang Gong University, Taoyun, Taiwan, {3. sichuan Univ Dept Polymer Sci & Mat Chengdu 610065 Sichuan Peoples R China Chang Gong Univ Dept Chem Engn Tao Yuan Taiwan

Solution crystallization of metallocene short chain branched polyethylene (SCBPE) was carried out and very nice single crystals were obtained. Compared with single crystals grown from linear polyethylene, SCBPE single crystals are dirty due to intermolecular heterogeneity The crystal morphology changes with crystallization temperatures. Lozenge, truncated lozenge, hexagonal, rounded and elongated crystal morphologies have been found at much lower crystallization temperature than in linear polyethylene. The electron diffraction shows there is a possibility that the single crystals may have hexagonal packing in a crystallization temperature range. The lateral habits of single crystal are discussed based on roughening theories.

关键词： metallocene SCBPE single crystal roughening face growth mechanism

The Relationship Among Bedrock Seismic Ground Motion Parameters with Different Exceedance Probabilities in the Panxi Area

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Earthquake Research in china 2003年第1期17卷 63-72页

作者： Lei JianchengSeismological bureau of sichuan Province, chengdu 610041, {3. Seismological bureau of sichuan Province Chengdu 610041 China

Based on the calculation of the bedrock effective peak acceleration (EPA) zoning map in the Panxi area, the ratios of EPA with exceedance probabilities of 63., 5%, 3., 2% and 1% over 50 years to that of 10% in 50 years are 0.3.2, 1.3., 1.55, 1.76 and 2.14, respectively. The seismic effect will be conservative and safe if taking this zoning map as the earthquake resistant fortification level and following the relevant rules of the Code for Seismic Design of Buildings (GBJ11 89) to calculate the seismic effect. Furthermore, the main factors that influence the A10/A63.ratios have been found to be the attenuation relationship of seismic ground motion, the division of seismic potential source regions and the seismicity parameters. These achievements are helpful to the spreading and applying of the zoning map.

关键词： Exceedance probability Bedrock seismic ground motion parameter Ratio

Study on the Reliability Evaluation of Qualitative Indices in Multi-Objective Decision

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Journal of Systems Engineering and Electronics 2002年第2期13卷 60-63页

作者： Zhang Mingshan , Tang Xiaowo & He Dequan( School of Economics and management, Southwest University for Nationalities, chengdu 610041, P.R.china School of management, University of Electronics Science and Technology, chengdu 610054, P.R.china School of School of Economics and management Southwest University for Nationalities Chengdu 610041 P. R. China School of management University of Electronics Science and Technology Chengdu 610054 P. R. China School of Economics and management Huadong Polytechnic University Shanghai 200237 P. R. China

Qualitative indices in multi-objective decision can usually be evaluated and measured by mathematical methods or models, but the obtained results are sometimes inaccurate because of fuzziness of indices. To improve the accuracy and reliability of the evaluation results, set-value statistic principle is applied, and accordingly four evaluation methods are obtained. Meanwhile, these methods are compared briefly.

关键词： Evaluation Fuzzy sets Mathematical models Reliability

Factors Affecting Transformation Temperatures in Fe-Mn-Si-Cr-Ni Shape Memory Alloy

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Journal of Materials Science & Technology 2000年第5期16卷 537-539页

作者： Yuhua WEN+, ding LI and Mingjing TU (Department of Materials Shaping and Controlling Engineering, sichuan University, chengdu 610065, china) Department of Materials Shaping and Controlling Engineering Sichuan University Chengdu 610065 China

The effects of prestrain and annealing temperature on phase transformation temperatures in Fel4Mn5Si8Cr4Ni shape memory alloy have been studied. The results showed that when the annealing temperature was 673.K, both the At and the Ms temperatures increased appreciably as the prestrain increased, the As temperature increased slightly with increasing prestrain; the resistivity difference at 3.3.K between the heating and cooling curve also increased with increasing prestrain, which agreed with the recovery strain. The shape memory effect in Fe-Mn-Si-Cr-Ni shape memory alloy is caused by the stress-induced γ→ε martensite transformation and its reverse transformation. When the prestrain was 10%, the Ms temperature decreased remarkably as the annealing temperature increased.

关键词： Factors Affecting Transformation Temperatures in Fe-Mn-Si-Cr-Ni Shape Memory Alloy Fe Mn Cr Ni Si

EFFECT OF PAN-MILLING STRESS ON CRYSTAL STRUCTURES OF HIGH DENSITY POLYETHYLENE

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Chinese Journal of Polymer Science 2000年第4期18卷 363-367页

作者： Hua Huang Polymer Research Institute, sichuan University, chengdu 610065, china School of chemistry and Chemical Technology,Shanghai Jiao Tong University ,Shanghai 200240,china sichuan Univ Polymer Res Inst Chengdu 610065 Peoples R China Shanghai Jiao Tong Univ Sch Chem & Chem Technol Shanghai 200240 Peoples R China

A detailed study was performed on the crystal structures of pan-milled high-density polyethylene (HDPE) using differential scanning calorimetry (DSC) and X-ray diffraction. The crystallinity of HDPE first decreased slightly, followed by a gradual increase with increasing milling times. Monoclinic crystals appeared after 4 cycles of milling. With increasing times of milling, the proportion of monoclinic crystals increased significantly while the proportion of orthorhombic crystals decreased gradually. With increasing times of milling, the crystallite size of orthorhombic form decreased greatly, while the size of monoclinic crystallites kept almost constant during milling.

关键词： high-density polyethylene pan-milling crystal structure

Completely regular paracompact reflection of locales

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Science china Mathematics 2006年第6期49卷 820-826页

作者： HE Wei & LUO Maokang Department of Mathematics, Nanjing Normal University, Nanjing 210097, china Department of Mathematics, sichuan University, chengdu 610064, china Department of Mathematics Nanjing Normal University Nanjing 210097 China Department of Mathematics Sichuan University Chengdu 610064 China

We give an explicit construction of the completely regular paracompact reflection pL of a completely regular locale L described as a sublocale of the Stone-tech compactification βL of L.

关键词： completely regular paracompact locale, nucleus.

A novel evolving model for power grids

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Science china(Technological Sciences) 2010年第10期53卷 2862-2866页

作者： LIU Xuan, LIU TianQi & LI XingYuan School of Electrical Engineering and Automation, sichuan University, chengdu 610065, china 1. School of Electrical Engineering and Automation Sichuan University Chengdu 610065 China

In this paper,a novel power grid evolving model,which can well describe the evolving property of power grids,is presented. Based on the BA model,motivated by the fact that in real power grids,connectivity of node not only depends on its degree,but also is influenced by many uncertain factors,so we introduce the subconnection factor K for each node. Using the mean-field theory,we get the analytical expression of power-law degree distribution with the exponent γ∈ (3.∞ ). Finally,simulation results show that the new model can provide a satisfactory description for empirical characteristics of power network,and power network falls somewhere in between scale-free network and uncertain network.

关键词： power grid evolving model scale-free