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Chinese Journal of Polymer Science 2005年第1期23卷 75-82页

作者： BoMenga Nai-taoYang Xiao-yaoTan Bao-yanZhang CollegeofChemicalEngineeringandTechnology ShandongUniversityofTechnologyZibo255049China SchoolofScience NortheasternUniversityShenyang110004China SchoolofScience NortheasternUniversityShenyang110004China／／CollegeofChemicalEngineeringandTechnologyShandongUniversityofTechnologyZibo255049China

Microporous polyvinylidene fluoride(PVDF)hollow fibre membranes were spun using the dry-wet phaseinversion *** means of dip-coating technique,a uniform coating with thickness of around 5-12 μm of polyvinyldimethylsiloxane(PVDMS)was formed on the surface of porous PVDF hollow *** structural parameters of PVDFsubstrate membrane were estimated by gas permeation *** N_2/O_2 as the medium,the separation properties ofPVDMS-PVDF composite hollow fiber membranes were also evaluated *** experimental data of bothpermeability and selectivity are in good agreement with the theoretical results predicted by the presented *** order to obtain the compact composite membrane free of defects by the dip-coating technique,the thickness ofPVDMS skin must be higher than 5 μm.

关键词： Hollow fiber composite membrane Gas separation Dip-coating method

A DFT Study on Intramolecular Hydrogen Bond in Substituted Catechols and Their Radicals

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Chinese Chemical Letters 2003年第2期14卷 209-212页

作者： Hong Yu ZHANG You Min SUN 等 LaboratoryforComputationalBiology ShandongProvincialResearchCenterforBioinformaticEngineeringandTechniqueShandongUniversityofTechnologyZibo255049 InstituteofTheoreticalChemistry S

Density functional theory (DFT) at B3LYP/6-31G(d,p) level was employed to calculate intramolecular hydrogen bond enthalpies (HIHB), O-H charge differences, O-H bond lengths and bond orders for various substituted catechols and their radicals generated after H-abstraction. It was found that although the charge difference between hydrogen-bonded H and O played a role in determining HIHB, HIHB was mainly governed by the hydrogen bond length. As the oxygen-centered radical has great tendency to form a chemical bond with the H atom, hydrogen bond lengths in catecholic radicals are systematically shorter than those in catechols. Hence, the HIHB for the former are higher than those for the latter.

关键词： Catechol catecholic radical density functional theory intramolecular hydrogen bond.

1, 4-Pyrone Effects on O-H Bond Dissociation Energies of Catechols in Flavonoids: A Density Functional Theory Study

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Chinese Chemical Letters 2002年第6期13卷 531-534页

作者： HongYuZHANG YouMinSUN 等 LaboratoryofComputationalBiology ShandongProvincialResearchCenterforBioinformaticEngineeringandTechniqueShandongUniversityofTechnologyZibo255091 InstituteofTheoreticalChemistry Sh

Through B3LYP/6-31G** calculations, the 1, 4-pyrone effects on O-H bond dissociation energies (BDEs) of catechols in rings A or B of flavonoids were investigated. For the catechol in ring A, although 1, 4-pyrone enlarged the conjugation system, its electron-withdrawing property increased the O-H BDE ∼ 3 × 4.184 kJ/mol compared with that of catechol. However, for the catechol in ring B, 1,4-pyrone was poorly conjugated with the moiety, and therefore, had little effect on the O-H BDE.

关键词： Antioxidant density functional theory flavonoid O-H bond dissociation energy structure-activity relationships.

Thermodynamic and Kinetic Studies on the SiH + XH_3 (X=N, P) Reactions

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Chinese Chemical Letters 2004年第5期15卷 627-630,F003页

作者： WeiJiangSI ShuPingZHUO GuanZhiJU SchoolofChemicalEngineering ShandongUniversityofTechnologyZibo255049 StateKeyLaboratoryofcoordinationChemistry NanjingUniversityNanjing210093

Based on the quantum chemical study of the silylidyne insertion reaction with NH3 or PH3, the general statistical thermodynamics and Eyring transition state theory with Wigner correction are used to compute the changes of thermodynamic functions, equilibrium constants, A factors and rate constants of the two reactions in the temperature range 200-2000K. The results show that both of these reactions are thermodynamically dominant at low temperatures and kinetically favored at higher temperatures. The comparison between these two reactions shows that the SiH reaction with NH3 is more exothermic than SiH with PH3, while the rate constant of SiH reaction with NH3 is lower than that of SiH with PH3 at the same temperature.

关键词： Silylidyne insertion reaction thermodynamic and kinetic studies.

Theoretical Investigation on Radical-Coupling Reactivity of Indolinonic Aminoxyls

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Chinese Chemical Letters 2003年第4期14卷 437-440页

作者： HongYuZHANG LanFenWANG DepartmentofChemistry ShandongTeachers‘UniversityJinan250014 LaboratoryforComputationalBiology ShandongProvincialResearchCenterforBioinformaticEngineeringandTechniqueShandongUniversityofTechnologyZ

Indolinonic aminoxyls can effectively scavenge various radicals by directly coupling with them or by imitating superoxide dismutase. To better understand the radical-coupling reactions, DFT method B3LYP/6-31G(d,p) was employed to calculate variations of free energy for the coupling reactions and other physico-chemical parameters. The radical-coupling activity difference between aminoxyls was elucidated to a large extent in terms of electronic properties of substituents.

关键词： Density functional theory indolinonic aminoxyl radical-coupling reaction.

Changing Rules of Bonding Electron Pair Correlation Energies of CH_3X (X=F,OH,NH_2) Systems

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Chinese Journal of Structural Chemistry 2004年第5期23卷 525-531页

作者： ZHUOShu-Ping SIWei-Jiang JUGuan-Zhi SchoolofChemicalEngineering ShandongUniversityofTechnologyZiboShandong255049China StateKeyLaboratoryofCoordinationChemistry DepartmentofChemistryNanjingUniversityNanjingJiangsu210093China

The pair correlation energy of bonding electrons is used and analyzed in the cal- culation of CH and CY (Y = F, O, N) bonding electron pairs in CH3X (X = F, OH, NH2) isoelec- tronic systems based on intra- and interpair correlation energy results at both MP2-OPT2/6- 311++G(d) and MP2-OPT2/cc-pVtz levels with MELD program. Comparison of two set results shows that cc-pVtz and 6-311++G(d) give more correlation energy of valence electrons and innermost core electron pairs, respectively in these systems, resulting that the total correlation energy with cc-pVtz basis of each system is larger than that with 6-311++G(d). Investigations of pair correlation energy show that with the decrease of electronegativity of X atom and the increase of H atoms in these CH3X (X = F, OH, NH2) systems, the pair correlation energy of 1sC2 of the C atoms is transferable, and the correlation energy of CH bonding electron pair with little changes is of approximate transferability, while those of CY (CF, CO, CN) bonding electron pair decrease in a large extent from CH3F through CH3OH to CH3NH2 molecules. It is suggested that the study of pair correlation energy of bonding electrons will further deepen the understanding of electron corre- lation effect from traditional chemical bonding concept.

关键词： pair correlation energy bonding electron pair CH3X systems

Short-range structural change in indium melt by Gaussian peaks decomposing of RDF

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Journal of University of Science and Technology Beijing 2002年第2期9卷 85-89页

作者： SujuanCheng ZhonghuaWang 等 TheKeyLaboratoryofLiquid＼StructureandHeredityofMaterials ShandongUniversityJinan250061China MechanicalEngineeringDepartment ShandongUniversityofTechnologyZibo255000China Shandon

Liquid indium's structure was studied at 280, 390, 550, 650, and 750 deg Crespectively by using an elevated temperature X-ray diffractometer, and its radial distributionfunction (RDF) at different temperatures was decomposed into 4 Gaussian peaks in the range of0.2-0.6nm. Positions of the decomposed Gaussian peaks were compared with the nearest and the secondnearest neighbor atomic distances, respectively. It is shown that the position of the firstdecomposed Gaussian peak is similar to the nearest neighbor atomic distance in liquid In at thecorresponding temperature, and that of the third decomposed Gaussian peak is similar to the secondnearest neighbor atomic distance. Moreover, the first and the third Gaussian peaks correspond to thefirst and the second atom shells of liquid In at the corresponding temperatures, ***, the position and the area of Gaussian peaks can represent the position and atom number ofcorresponding shells. Based on this result, short-range structural changes in liquid In wasstudied. It was found that the first and the second shells are close to the referred atom, and theatom number at the shells decreases with the increasing temperature from 280 to 750 deg C. Indifferent ranges of temperature, structural changes in the first and the second shells showdifferent features.

关键词： radial distribution function Gaussian peaks decomposing short-rangestructure atom shell

APPLICATION OF SUB-ELEMENT AND MICRO-ELEMENT IN BEM WITH ROLLER BEARING LOAD

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Chinese Journal of Mechanical Engineering 2004年第3期17卷 423-426页

作者： ShuXuedao XingXidong DepartmentofMechanicalEngineering UniversityofScienceandTechnologyBeijingBeijing100083China DepartmentofMechanicalEngineering ShandongUniversityofTechnologyZibo255049China

Aiming at the discontinuous traction on contact elements of roller bearing,new concepts of sub- and micro-element are put forward. In the sub-element and micro-element,traction influence coefficient has been modified, which is calculated by the former boundary elementmethod (BEM) with roller bearing load. Hence, three-dimensional distribution of load on rollerbearing is calculated accurately. In practice, it has been proved that this method has highercalculation accuracy. An effective numerical method is offered for analyzing load characteristics ofroller bearing to improve service longevity of roller bearing and operation efficiency of rollingmill.

关键词： Sub-element Micro-element BEM

MEDIUM-RANGE ORDER CLUSTERS IN Fe-2.0%C ALLOY MELT

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Acta Metallurgica Sinica(English Letters) 2003年第6期16卷 513-518页

作者： X.B.Qin S.J.Cheng X.F.Bian KeyLaboratoryofLiquidStructureandHeredityofMaterials MinistryofEducationShandongUniversityJi‘nan250061China MechanicalEngineeringDepartment ShandongUniversityofTechnologyZibo255000China

The structure of Fe-2.0%C alloy melt was investigated at 1580, 1560, 1540 and 1450℃ by using an X-ray diffractometer respectively. The results showed that with decreasing temperature, the average atoms of cluster, the coordination numbers, the correlation radius and the atom density increased, whereas the pre-peak of the structure factors curve remained almost at the same position. The appearance of the pre-peak indicated that the liquid structure and the solid structure of the Fe-2.0%C alloy were correlated.

关键词： liquid structure X-ray diffraction micro-inhomogeneous model,pre-peak structure factor

Viscosity of In and In-Sballoys

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Rare Metals 2003年第1期22卷 64-68页

作者： ZHANGJunyan WANGZhonghua CHENGSujuan BIANXiufang QINXubo ShandongDachengPesticideCo.Ltd Zibo255000China shandonguniversityoftechnology Zibo255000China TheKeyLaboratoryofLiquidStructureandHeredityofMaterials MinistryofEducationShandongUniversityJinan2500

The dynamic viscosity of pure In, In-1%Sb (mass fraction, so as the follows) alloy, In-55%Sb hypoeutectic alloy and In-69.5%Sb eutectic alloy was measured by using a torsional oscillation viscometer at different temperatures above liq-uidus. The experimental results show that the viscosity of these melts decreases with increasing temperature. The anomalous change of viscosity occurs at about 430 and 470℃in pure In melt. The variation of viscosity with temperature well meets exponential correlation and no anomalous change occurs in measured temperature range in the In-1%Sb alloy melt. A transition occurs at about 800℃ in both of In-55%Sb and In-69.5%Sb alloy melts. The sudden change of viscosity suggests the structure change of melts. DSC (differential scanning calorimetry) curves of In-1%Sb alloy during heating and cooling were measured, and the results show that no structural variation in In-1%Sb alloy melt was testified further. In addition, the viscosity of In melt decreases with the addition of1%Sb.

关键词： melt viscosity differential scanning calorimetry (DSC) In In-Sb alloy