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多孔钛的制备及磷灰石涂层的仿生沉积

四川大学学报（自然科学版） 2003年第4期40卷 700-703页

作者：张其翼陈继镛张兴栋四川大学生物材料工程研究中心

作者提出了制备多孔金属材料的有效方法:利用混和金属粉末和有机粘稠剂,经双氧水发泡和烧结,可得到多孔材料,其材料的孔隙率和孔径大小能在制备过程中进行控制;采用钛珠在真空中烧结形成多孔钛结构亦可制备了多孔钛.制成多钛孔材料后,... 详细信息

作者提出了制备多孔金属材料的有效方法:利用混和金属粉末和有机粘稠剂,经双氧水发泡和烧结,可得到多孔材料,其材料的孔隙率和孔径大小能在制备过程中进行控制;采用钛珠在真空中烧结形成多孔钛结构亦可制备了多孔钛.制成多钛孔材料后,采用一种简单的沉积方法在上述两种多孔钛表面沉积磷灰石涂层,试验表明,沉积的涂层在不同的基体表面上呈现出不同的特征形貌,在光滑的活性表面,可形成晶种均匀.晶体呈片状生长的网状结构;在基体的粗糙、尖锐处,其基体表面能高,可形成更多的晶种,而晶体生长受限,仅能形成亚微米级的团聚微晶.

关键词：多孔钛仿生沉积磷灰石涂层

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 {2., sichuan university, chengdu 610065, china 2. college of Physics, sichuan university, chengdu 610065, china college of chemical {2. 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

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 {2.,sichuan university,chengdu 610065,china 1. college of chemical {2. 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

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(Physics,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 Physics, college of chemical {2., sichuan university, chengdu 610065, china 2. Institute of Theoretical Physics, Xihua Normal university, Nanchong 637002. china 3. Department of Physics, china Oceanography university, Qingdao 2.6003, china 4. college of Physics, sichuan university, chengdu 610065, china 1. Institute of Physics College of Chemical Engineering Sichuan University 610065 Chengdu China 2. Institute of Theoretical Physics Xihua Normal University 637002 Nanchong China 3. Department of Physics China Oceanography University 266003 Qingdao China 4. college of Physics 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.

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,{2., sichuan, china 2. college of Mechanical engineering, sichuan university of Science and engineering, Zigong 643000, sichuan, china) [a] college of Architecture and Environment. sichuan university Chengdu 610065 Sichuan China [b] college of Mechanical engineering.{2. 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

A new grid-associated algorithm in the distributed hydrological model simulations

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Science china(Technological Sciences) 2010年第1期53卷 235-241页

作者： XU Rui1,2.HUANG XiaoXue1,LUO Lin1 & LI ShaoCai3 1 State Key Laboratory of Hydraulics and Mountain River engineering college of Architecture and Environment,{2. university,chengdu 610065,china 2.college of Electronic engineering,Guilin university of Electronic Technology,Guilin 541004,china 3 college of Life Sciences,{2. university,chengdu 610065,china 1. State Key Laboratory of Hydraulics and Mountain River engineering college of Architecture and Environment Sichuan University Chengdu 610065 China2. College of Electronic Engineering Guilin University of Electronic Technology Guilin 541004 China3. College of Life Sciences Sichuan University Chengdu 610065 China

This paper presents a new grid-associated algorithm to improve the performance of a D8 algorithm based distributed hydrological model *** algorithm is based on the well known single-flow D8 algorithm of grid *** algorithm allocates calculation priorities according to the distance between the units and the outlet,then carries out the ergodic computations of the hydrological units according to the priority *** the parallelized algorithm,a standard thread-level shared memory system for parallel programming(OpenMP-Open specifications for Multi Processing) was introduced,and the parallel coding was implemented in C lan-guage.A case study showed that the absolute speed-up ratio of the grid-associated algorithm is 1.64 over the original D8 algorithm,and the linear speed-up ratio of the parallel associated algorithm is 2.42.under 4 *** parallel grid-associated algorithm can be applied to a variety of research fields that use the grid method.

关键词： distributed hydrological model grid-association algorithm OpenMP parallel computing

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

Encapsulation of inorganic particles by dispersion polymerization through ultrasonic irradiation

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Science china Chemistry 2005年第6期48卷 545-552页

作者： ZHANG Kai1,2. FU Qiang1, HUANG Yuhong2.& ZHOU Dehui2.1. college of Polymer Science and engineering,{2., chengdu 610065, china 2. Institute of Structure Mechanics, china Academy of engineering Physics, Mianyang 62.900, china 1. college of Polymer Science and engineering Sichuan University 610065 Chengdu China 2. Institute of Structure Mechanics China Academy of Engineering Physics 621900 Mianyang China

The nano-silica/polystyrene composite particles were prepared and characterized according to the following steps. First, the nano-silica particles were pretreated with surfactants under ultrasonic field. Second, the dispersion polymerization of styrene in a water/ethanol (1/6, weight ratio) medium, with poly(N-vinyl pyrrolidone) (PVP) as stabilizer and 2.2.-azobisizobu- tyronitrile (AIBN) as initiator in the presence of nano-silica particles was initiated with N2.purging through ultrasonic irradiation by taking its advantages of multieffect, i.e. dispersion, crushing, activation, and initiation. Finally, the polymerization kinetics characteristics were studied, and the encapsulation of composite particles was investigated with optical microscope, SEM, TEM, FTIR, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).

关键词： composite particle, dispersion polymerization, ultrasonic irradiation.

One approach to calculating the solvent reorganization energy of intramolecular electron transfer

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Chinese Science Bulletin 2003年第1期48卷 35-38页

作者： FU Kexiang1,2. LI Xiangyuan1, ZHU Quan1 & LU Shenzhuang1 1. college of chemical {2., sichuan university, chengdu 610065, china 2. college of Physics, sichuan university, chengdu 610064, china Correspondence should be addressed to Li Xiangyuan (e-mail: xyli@***) college of chemical {2. Sichuan University Chengdu 610065 China college of Physics Sichuan University Chengdu 610064 China

On the basis of the electromagnetic field theory and the spherical cavity approximation, the expressions ofGibbs free energies under equilibrium and non-equilibrium solvation conditions are obtained by solving the electrostatic potential equations with boundary conditions. The surface charges produced by the orientational polarization of equi-librium solvation are taken fixed in the case of non-equilibrium situation, for the slow-response of the orientational polarization to electron transfer of the solvent molecules. Anew expression of solvent reorganization energy has beenobtained and this method is applied to the electron transfer systems, NO+/NO, NO2./NO2. and NO2./NO. The solvent reorganization energies have been evaluated.

关键词：分子内电子传递溶剂重排能定向极化自由能电子极化计算方法