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Effect of alloying elements on valence electron structure (VES) of Fe-3Al intermetallic compounds

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Chinese Science Bulletin 1998年第2期43卷 169-170页

作者： Sun, KN Zhang, JD Yin, YS Shandong Univ Technol Jinan 250061 Peoples R China

The hybridized state of each atom changes with various changes of alloying elements and different alloying degrees. It is shown that during the course of alloying, the changes in the microsolid_state reflection such as atomic hybridized state make the corresponding VES parameters change, and that affects the mechanical properties of Fe-3Al alloys.

关键词： alloy valence electron structure.

Synthesis, Characterization and Crystal Structure of Chlorodibenzyltin(IV) Complex with Dithiomorpholinocarba-mate Ligand

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Chinese Journal of Chemistry 2002年第9期20卷 913-916页

作者：尹汉东王传华马春林王勇 Department of Chemistry Liaocheng Teachers University Liaocheng 252059

Chlorodibenzyltin(IV) complex with dithiomorpholinocarba mate ligand was synthesized by the reaction of dibenzyltin dichloride with dithiomorpholinocarbamate in 1∶1 stoichiometry. The complex was characterized by elementary analysis, UV, IR and 1H NMR spectra. The crystal structure was determined by X ray single crystal diffraction study. The crystallographic data are as follows: triclinic, space group P 1, a =0 8723(2) nm, b =1 099(2) nm, c =1 1036(3) nm, α =86 498(4)°, β =89 697(5)°, γ =82 807(5)°, Z =2, V =1 0479(4) nm 3, D c=1 580 g/cm -3 , μ =1 553 mm -1 , F (000)=500, R 1=0 0442, wR 2=0 0974. The crystal consists of discrete molecules containing five coordinate tin atoms in a distorted tigonal bipyramidal configuration. The molecules are packed in the unit cell in one dimensional chain structure through a weak interaction between the chlorine atom and sulfur atom, the sulfur atom and one of the sulfurs of an adjacent molecule.

关键词： chlorodibenzyltin(IV) complex dithiomorpholino carbamate crystal structure S...S and S...Cl interactions

Synthesis and Molecular Structure of Binuclear Tin(IV) Complex Bridged by Terephthalate Anion

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Chinese Journal of Chemistry 2002年第6期20卷 614-616页

作者：尹汉东王传华马春林王勇 Department of Chemistry Liaocheng Teachers University Liaocheng 252059 China

The title complex [Ph 3Sn(CH 3OH)(terephthalate)(CH 3OH)SnPh 3]·2CH 3OH was synthesized by the reaction of Ph 3SnCl with terephthalate in the molar ratio of 2∶1 in methanol solution and characterized by elemental analysis, IR and 1H NMR spectra, and the crystal structure was determined by X ray single crystal diffraction study. The crystal belongs to monoclinic with space group P 2 1/ n , a =1.5199(5) nm, b =0.9000(3) nm, c =1.8206(6) nm, β=113.970(5)°, Z =2, V =2.2755 (13) nm 3, D c=1.413 g/cm 3, μ =1.146 mm -1 , F (000)=980, R =0.0353, wR =0.0606. In the crystals of complex, the tin atoms rendered five coordinate in a distorted tirgonal bipyramidal structure.

关键词： binuclear triphenyltin(IV) terephthalate synthesis molecular structure

Synthesis, Properties and Crystal Structure of Seven-coordinated Organotin Complex [~nBu_2Sn(OOCC_5H_4N-2)_2(H_2O)]

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Chinese Journal of Chemistry 2002年第12期20卷 1608-1611,1464页

作者：尹汉东王传华马春林王勇 Department of Chemistry Liaocheng University Liaocheng Shandong 252059 China

A novel seven-coordinated organotin complex [ nBu 2Sn-(OOCC 5H 4N-2) 2(H 2O)] was unexpectedly synthesized by reaction of nBu 3SnCl with 2-pyridinecarboxylic acid in 1∶1 molar ratio in the presence of organic base Et 3N. The crystal structure was determined by single crystal X-ray diffraction analysis. The crystal belongs to rhombohedral with space group R-3c, a=1.5807(3) nm, b=1.5807(3) nm, c=1.5807(3) nm, α=105.717(2)°, β=105.717(2)°, γ=105.717(2)°, Z=6, V=3.397(8) nm 3, D c=1.452 g/cm 3, μ=1.158 mm -1, F(000)=1512, R 1=0.0447, wR 2=0.1038. In crystal, the tin atoms rendered seven-coordinate in a distorted pentagonal bipyramidal geometry. The two-dimensional network structure was formed by H-bonding interaction between the free oxygen atoms of carboxyl groups and the coordinated water molecules.

关键词： organotin complex 2-pyridinecarboxylic acid synthesis crystal structure

Structures of N-(2,3,4,6-Tetra-O-acetyl-β-D-glycosyl)thiocarbamic Benzoyl Hydrazine

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Chinese Journal of Chemistry 2002年第2期20卷 183-186页

作者：张书圣林洁华建方方焦奎 Department of Applied Chemistry Qingdao Institute of Chemical Technology Qingdao Shandong 266042 China

The crystal structure ofN-(2,3,4,6-tetra-O-acetyl-β-D-glycosyl)-thiocarbamic benzoyl hydrazine ( C_(22)H_(27)N_3O_9S) wasdetermined by X-ray diffraction method. The hexopyranosyl ring adopts a chair conformation. All thering suhstituents are in the equatorial positions. The acetoxyl-methyl group is in synclinalconformation. The S atom is in synperiplanar conformation while the benzoyl hydrazine moiety isanti-periplanar. The thiocarbamic moiety is almost coplanar with the benzoyl hydrazine group. Thereare two intramolecular hydrogen bonds and one intermolecular hydrogen bond for each molecule in thecrystal structure. The molecules form a network structure through intermolecular hydrogen bonds.

关键词： crystal structure hydrogen bonds conformation

Structure and Interconnected Stabilization of the Multi-groups Multi-delays Neutral Linear Time- Invariant Interconnected Control Systems with theTime-Delay Input Control

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生物数学学报 1997年第4期12卷 289-298页

作者： GaoCunchen ZhangXinzheng LiuYongqing,DepartmentofAutomaticControlEnineering,SouthChinaUniversityofTechnology，Guangzhou510641 烟台教师进修大学计算机科学和数学系山东烟台 264025 中南工业大学自动控制工程系湖南长沙

Abstract:Somenewconceptsofthestructureandinterconnectedstabilizationareestablishedforthemulti-groupmulti-delaysneutrallineartime-invariantinterconnectedcont***-tivedefinitequadraticformV-functionviachoosingthesymmetricpositivedefinitesolu-tionmatrixofRiccatimatrixalgebraicequationismadeup,theinterconnectedstabiliza-tionofthelineartime-invariantcontrolsystemwithoutdelaysandPerturbationParame-tersimplytheinterconnectedstabilizationofthemulti-groupmulti-delaysneutrallineartime-invariantinterconnectedcontrolsystemwiththetime-delayinputcontrolandper-turbation***,someestimateformulaeoftheboundedforbothtime-delaysandper-turbationparametersaregiven．

关键词： Keywords:Interconnectdstabilization,multi-groupmulti-delays,controlsys-tem,neutraltime-invariant,Lyapunovfuncti

Derivatization Reaction of Carbohydrates with Urea as the Reagent and Fluorimetric Determination of Carbohydrates

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Chinese Journal of Chemistry 2002年第1期20卷 51-56页

作者：杨景和曹西慧王敏吴霞孙长侠 Key Laboratory of Colloid & Interface Chemistry for Education Ministry Department of Chemistry Shandong University Jinan Shandong 250100 China

It is found that in the presence of sulfuric acid carbohydrates condense withurea to afford the condensation products, which emit fluorescence. Under optimum conditions, thefluorescence intensities of system are proportional to the concentrations of carbohydrates. Based onthis linear relationship, quantitative determination of kinds of carbohydrates has been made. Amongall the carbohydrates tested, the sensitivity of α-rhamnose is the highest and its limits ofdetection reaches 3. 5 * 10^(-8) mol/L. So α-rhamnose can be selectively determined in the presenceof other carbohydrates. A interaction mechanism is also discussed.

关键词： carbohydrate urea derivatization reaction fluorimetric determination

Theoretical Study on the Kinetics of Electron Transfer for Bond-breaking Reaction

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Chinese Journal of Chemistry 2002年第6期20卷 539-544页

作者：邢玉梅周正宇高洪伟 DepartmentofChemistry QufuNormalUniversityQufuShandong273165China

To test the theory of dissociative electron transfer, a simple model describing the kinetics of electron transfer bond breaking reactions was used. The Hamiltonian of the system was given. The homogeneous and heterogeneous kinetic data fit reasonably well with an activation driving force relationship derived from the Marcus quadratic theory. In the heterogeneous case, there is a good agreement between the theoretical calculation and the experimental result, while in the homogeneous case, a good agreement is only observed for the tertiary halides. This is due to the stability of tertiary radical resulting from the sterical effect.

关键词： electron transfer bond breaking reaction butyl halide

Cutting tool materials for high speed machining

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Progress in Natural Science:Materials International 2005年第9期15卷 777-783页

作者： LIU Zhanqiang** and AI Xing(School of Mechanical Engineering, Shandong University, Jinan 250061, China) School of Mechanical Engineering Shandong University Jinan 250061 China

High speed machining (HSM) is one of the emerging cutting processes, which is machining at a speed significantly higher than the speed commonly in use on the shop floor. In the last twenty years, high speed machining has received great attentions as a technological solution for high productivity in manufacturing. This article reviews the developments of tool materials in high speed machining operations, and the properties, applications and prospective developments of tool materials in HSM are also presented.

关键词： tool materials high speed machining.