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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2)molecule

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Science China(phys.cs,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2, SUN Weiguo1, HOU Shilin3 & FENG Hao4.1. Institute of phys.cs, college of Chemical Engineering, sichuan university, chengdu 610065, China 2. Institute of Theoretical phys.cs, Xihua Normal university, Nanchong 637002, China 3. Department of phys.cs, China Oceanography university, Qingdao 266003, China 4. college of phys.cs, sichuan university, chengdu 610065, China 1. Institute of phys.cs College of Chemical Engineering Sichuan University 610065 Chengdu China 2. Institute of Theoretical phys.cs Xihua Normal University 637002 Nanchong China 3. Department of phys.cs China Oceanography University 266003 Qingdao China 4. college of phys.cs Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2 molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

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EFFECT OF PAN-MILLING ON RHEOLOGICAL PROPERTIES OF HIGH DENSITY POLYETHYLENE

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Chinese Journal of Polymer Science 2000年第5期18卷 397-403页

作者： Hua Huang Polymer Research Institute, sichuan university, chengdu 610065, China sichuan Univ Polymer Res Inst Chengdu 610065 Peoples R China Shanghai Jiao Tong Univ Sch Chem & Chem Technol Shanghai 200240 Peoples R China

The effect of pan-milling on the rheological properties of high density polyethylene (HDPE) was studied. An innovative milling apparatus, viz. an inlaid pan-mill, was used. Melt indexer, capillary rheometer, Haake Rheocord 90 single-screw extruder and Brabender rheometer were used to evaluate the rheological properties of HDPE. HDPE with higher initial molecular weight and larger particle size was easier to degrade under pan-milling stress, as indicated by the melt index. Pressure oscillation in capillary flow occurred at significantly higher shear stress and shear rate for milled HDPE than for unmilled HDPE. The apparent shear viscosity of HDPE decreased with increasing times of milling. After milling, the flow activation energy decreased and thus the sensitivity of viscosity to temperature was reduced. Die pressure and torque during single screw extrusion were reduced significantly after milling. Plasticizing time as measured in a Brabander mixer decreased markedly with increasing milling times.

关键词： high density polyethylene rheological properties pan-milling

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Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2,3 , ZHOU Wancun 1 ,ZHOU Jieming 4., ZHU Mingcang 3,5 1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences , chengdu 61004., sichuan, China 2. Graduate university of Chinese Academy of Sciences, Beijing 10004., China 3. sichuan Institute of Land Resource Management, chengdu 61004., sichuan , China 4. Department of Resources and Environment Science, sichuan Normal university , chengdu 610061, sichuan, China 5. college of Information Engineering, chengdu university of Technology, chengdu 610059, sichuan, China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate university of Chinese Academy of Sciences Beijing China sichuan Institute of Land Resource Management Chengdu Sichuan China Department of Resources and Environment Science Sichuan Normal University Chengdu Sichuan China college of Information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3 ,HUANG Zhiqin 2, 3, 4.1. The Faculty of Geography and Resources Science, sichuan Normal university, chengdu 610066, sichuan, China 2. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, chengdu 61004., sichuan, China 3. Graduate university of the Chinese Academy of Sciences, Beijing 10004., China 4. Information Center of Land and Resources Department of sichuan Province, chengdu 61004., sichuan, China The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate university of the Chinese Academy of Sciences 100049 Beijing China Information Center of Land Resources Department of sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

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CHARACTERISTIC ANALYSIS OF THE PLUNGING OF TURBIDITY CURRENTS

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Journal of Hydrodynamics 2010年第2期22卷 274-282页

作者： AN Rui-dong LI Jia State key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China college of Water Recourse and Hydropower Sichuan University Chengdu 610065 China

Turbidity currents are flows driven by suspended sediment of flood-induced turbid river water with excess *** currents are often the governing factor in reservoir sedimentation by transporting fine materials over long distances and delivering the majority of deposition,which thus reduces the storage ***,the design and operation of a reservoir requires an accurate prediction of its occurrence condition and plunging position,which is the objective of the present *** article presents a verified algebraic slip mixture model including momentum,continuity and algebraic velocity expressions to simulate 2-D turbidity *** experiments in a multiphase flume were carried *** number,sediment concentration and densimetric Froude number were used as parameters in the occurrence condition *** plunging of turbidity currents may produce reflux and backflow due to the diving flow at the surface of the clear *** similar experimental results were also obtained by PIV measurements

关键词： turbidity current plunge suspend sediment algebraic slip mixture model densimetric Froude number

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A Study on the Effects of the Surrounding Faults on Water Loss in the Zoige Wetland,China

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Journal of Mountain Science 2011年第4期8卷 518-524页

作者： LI Mei XU Rui HUANG Wendian SUN Hailong LUO Lin State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China. college of Life and Environmental Science Guilin University of Electronic Technology Guilin 541004 China. college of Arehiteeture and Environment Sichuan University Chengdu 610065 China college of live Science Sichuan University Chengdu 610065 China

The Zoige wetland is the biggest alpine wetland in the world,and an important water resource of the Yellow *** to natural and human factors,the Zoige wetland has been seriously *** studies on the Zoige wetland mainly focus on the macro features of the wetland,while the influence of the surrounding faults on the Zoige wetland degradation is rarely *** study uses terrain data to analyze the cover change and the water loss caused by the Wqie-Seji fault based on the distributed hydrological *** simulated water loss demonstrates that the Normalized Difference Vegetation Index(NDVI) is the most important factor for inducing water *** fault is also a factor that cannot be neglected,which has caused 33% of the wetland water ***,it is of importance to study the influence of the fault on the wetland degradation.

关键词： Hydrological model Fault Degradation Water loss Zoige Wetland

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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, sichuan university, chengdu 610065, China 2. college of {4., sichuan university, chengdu 610065, China college of Chemical Engineering Sichuan University Chengdu China college of phys.cs 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

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Theoretical Studies of Energy Spectra and g Factors of Cr3+-Doped YAl3(BO3)4

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Communications in Theoretical phys.cs 2006年第6期45卷 1121-1125页

作者： ZHANG Ji-Ping CHEN Gang ZHOU Hua-Bin college of physical Science and Technology,sichuan university,{4. 610065,China college of physical Science and Technology Sichuan University

Abstract With the strong-field scheme and trigonal bases,by diagonalizing the complete d~3 energy matrix in atrigonally distorted cubic-field,the energy spectra and wavefunctions of YAl(BO):Crhave been *** of change of levels with respect to various parameters and the contributions to levels from various parametersare calculated,and the physical origins of various levels or splittings have been clearly and quantitatively *** the wavefunctions obtained from diagonalizing the complete energy matrix,the g factors of the ground state ofYAl(BO):Crhave been *** calculated results are in good agreement with the optical-spectral and EPRexperimental *** is demonstrated that the bonding between Cand ligands(O)is ionic.

关键词： :crystal fields energy spectrum g factor electronic paramagnetic resonance

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Vertical ionization energies of halogen anions in solution

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Science China Chemistry 2010年第6期53卷 1316-1321页

作者： CHENG XueMin,ZHU Quan,WANG XingJian,LI YunKui & LI XiangYuan college of Chemical Engineering,sichuan university,chengdu {4.,China 1. college of Chemical Engineering Sichuan University Chengdu 610065 China

Based on the constrained equilibrium state theory,the nonequilibrium solvation energy is derived in the framework of the continuum *** formula for spectral shift and vertical ionization energy are deduced for a single sphere cavity with the point charge *** new model is adopted to investigate the vertical ionization for halogen atomic and molecular anions X(X = Cl,Br,I,Cl2,Br2,I2) in aqueous *** to the calculation using the CcsD-t/aug-cc-pVQZ method in vacuum,our final estimated vertical ionization energies in solution are very close to the experimental observations,while the traditional nonequilibrium solvation theory overestimates these vertical ionization energies.

关键词： vertical ionization energy spectral shift constrained equilibrium state

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AN INVESTIGATION OF FLOW CHARACTERISTIC OF AERATED DRAG REDUCTION IN TUBE

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Journal of Hydrodynamics 2002年第3期14卷 102-105页

作者： Dai Guang qing, Yang Qing State Key Hydraulics Laboratory of High Speed Flows, sichuan university, chengdu 610065, ChinaZhang Rong Net Education Institute, sichuan university, chengdu 610065, China Hydraulics Lab. of High Speed Flows Sichuan Univ. Chengdu 610065 China

Under the aerated conditions of wall and top in tube, the turbulent flow in the tube was measured by using LDA. The turbulent structure of the flow field and the mechanism of aerating drag reduction in the tube were discussed. It is shown that the energy dissipations of turbulence flow and mean flow will reduce and the flow velocity (or flow rate) will increase by injecting mini bubbles to the wall or top of tube, namely the effect of aerating drag reduction is attained.

关键词： tube turbulent flow aeration drag reduction

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