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Properties of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin liquid crystal Co and Ni complexes

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Science china Chemistry 2007年第4期50卷 488-493页

作者： LIU Wei1,2.& SHI TongShun2.1 College of Materials Science and Engineering, Shandong university of Technology, Zibo 2.5049, china 2.Department of Chemistry, {2. university, changchun 13002., china College of Materials Science and Engineering Shandong University of Technology Zibo China Department of Chemistry Jilin University Changchun China

Six series of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin Co and Ni complexes (12.kinds) were reported. Nine of the compounds were found to exhibit liquid crystal properties and display a hexagonal columnar discotic columnar (Colh) phase. Molecular structure of all synthesized compounds was confirmed by IR, UV, MS, 1H NIVR, and elemental analysis. These liquid crystalline compounds have been studied by cyclic voltammetry, luminescence, and surface photovoltage spectroscopy.

关键词： porphyrin liquid crystal cyclic voltammetry luminescence surface photovoltage spectroscopy

Kernel model-based diagnosis

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Progress in Natural Science:Materials International 2002年第2期12卷 63-67页

作者： OUYANG Dantong(Department of Computer Science, jilin university, {2. 130012. china) jilin Univ Dept Comp Sci Changchun 130012 Peoples R China

The methods for computing the kernel consistency-based diagnoses and the kernel abductive diagnoses are only suited for the situation where part of the fault behavioral modes of the components are known. The characterization of the kernel model-based diagnosis based on the general causal theory is proposed, which can break through the limitation of the above methods when all behavioral modes of each component are known. Using this method, when observation subsets deduced logically are respectively assigned to the empty or the whole observation set, the kernel consistency-based diagnoses and the kernel abductive diagnoses can deal with all situations. The direct relationship between this diagnostic procedure and the prime implicants/implicates is proved, thus linking theoretical result with implementation.

关键词： model-based diagnosis general causal theory prime implicant/implicate diagnostic space.

THE STABILITY AND CONVERGENCE OF COMPUTINGLONG-TIME BEHAVIOUR

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Journal of Computational Mathematics 1999年第4期17卷 397-418页

作者： HaI-jun Wu Rong-hua Li(Institute of Mathematics, jilin university, {2. 13002., china) 吉林大学数学系吉林长春 130023 吉林大学数学系吉林长春

The object of this paper is to establish the relation between stability and convergence of the numerical methods for the evolution equation u(t) - Au - f(u) = g(t) on Banach space V, and to prove the long-time error estimates for the approximation solutions. At first, we give the definition of long-time stability, and then prove the fact that stability and compatibility imply the uniform convergence on the infinite time region. Thus, we establish a general frame in order to prove the long-time convergence. This frame includes finite element methods and finite difference methods of the evolution equations, especially the semilinear parabolic and hyperbolic partial differential equations. As applications of these results we prove the estimates obtained by Larsson [5] and Sanz-serna and Stuart [6].

关键词： stability compatibility covergence reaction-diffusion equation long-time error estimates

A scheme for the RCP pattern of the nano-structure

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Communications in Nonlinear Science and Numerical Simulation 2001年第4期6卷 201-204页

作者： Guangwu YAN, Hongxue QU and Bing YAN Department of Mathematics, jilin university, {2. 130012. china Institute of Atomic and Molecular Physics, jilin university. {2. 13002., china Department of Mathematics Juin University Changchun 130012 China Inst. of Atom. and Molecular Physics Jilin University Changchun 130023 China

A new scheme for the Random-Continuous-Pile (RCP) pattern is proposed to simulate a two-dimensional structure The RCP pattern is plotted.

关键词： RCP pattern. Maxwell distribution balls-filling

COMPARISON　THEOREMS　TO　BOUNDARY　VALUE　PROBLEMS　FOR　ORDINARY　DIFFERENTIAL　EQUATIONS

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Chinese Annals of Mathematics,Series B 1994年第2期15卷 165-172页

作者： LI YONG WANG HUAIZHONG(Department of Matehematics,jilin university, {2. 13002., jilin, china) jilin UNIV DEPT MATHCHANGCHUN 130023PEOPLES R CHINA

A unified approach is given to several classes of nonlinear boundary value problems, and some previous existence theorems are extended.

关键词： Boundary value problem Existence theorem Brouwer degree,Schauder's fixed point theorem.

Investigation on Vibrational Spectra and Structures of 4-Mercaptopyridine Monomer and Its Dihydrate

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Chemical Research in Chinese Universities 2006年第1期22卷 90-93页

作者： CHENG Jian-bo 1,2., XUE Wei-qing 1 , ZHAO Bing 1** , ZHANG Gang 3 and GONG Bao-an 2.1. Key Laboratory for Supramolecular Structure and Material of Ministry of Education, jilin university, {2. 130012. P. R. china 2. Science and Engineering College of Chemistry and Biology, Yantai university, Yantai 2.4005, P. R. china 3. State Key Laboratory of Theoretical and Computational Chemistry, jilin university, {2. 13002., P. R. china Key Laboratory for Supramolecular Structure and Material of Ministry of Education Jiln University Changchun 130012 P. R. China Science and Engineering College of Chemistry and Biology Yantai University Yantai 264005 P. R. China State Key Laboratory of Theoretical and Computational Chemistry Jiln University Changchun 130023 P. R. China

The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory(DFT), viz. B3LYP method with the 6-311++G(d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the dihydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be consi- derably affected by the water molecules.

关键词： 4MPY Dihydrate Vibrational spectra DFT Molecular structure

A Study of Mechanical Properties of the Iron-base Sintered Steel Adding Fine Cr-Fe Powder

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稀有金属材料与工程 2011年第S3期40卷 5-8页

作者： Chen Hua 1 , Liu Yongbing 2., Li Yueying 2., Cao Zhanyi 2., Chai Zhilong 3 1 Key Laboratory of Advanced Structural Materials, Ministry of Education, changchun university of Technology, changchun 130012. china 2.Key Laboratory of Automobile Materials, Ministry of Education, jilin university, changchun 13002.,china 3 Research Institute of First Automobile Factory of china, changchun 130011, china changchun Univ Technol Sch Mat Sci & Engn Key Lab Adv Struct Mat Minist Educ Changchun 130012 Peoples R China jilin Univ Key Lab Automobile Mat Minist Educ Changchun 130022 Peoples R China Res Inst First Automobile Factory china Changchun 130011 Peoples R China

This paper reports an investigation of the mechanical properties and the fracture mechanism of iron-based sintered alloy containing fine Cr-Fe powder particles 300 nm in size and in contents raging from 0.2.1.5 wt%. The iron-base alloy were sintered at 112. ℃ for 40min. The results of the study revealed improvement in mechanical properties such as tensile strength, elongation and hardness of the sintered alloy. The fracture behaviors of the alloy were influenced significantly by the presence of Cr-Fe powder particles. The mechanical properties increased with increasing Cr content. Micrographs of fracture appeared dimple and quasi-cleavage.

关键词： sintered steel fine Cr-Fe powder mechanical properties

DFT evaluation of the electronic structures and spectroscopic properties of the self-assembled [Pt_2._4(C≡CH)_8](M=Cu,Ag) clusters

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Science china Chemistry 2009年第11期52卷 1954-1960页

作者： BAI FuQuan1,XIA BaoHui1,2.ZHANG HongXing1,YANG BaoZhu1,WANG Jian1 & SUN Lei1 1 State Key Laboratory of Theoretical and Computational Chemistry,Institute of Theoretical Chemistry,jilin university,{2. 13002.,china 2.College of Chemistry,jilin university,{2. 13002.,china State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun China College of Chemistry Jilin University Changchun China

Electronic structures and spectroscopic properties of self-assembled [Pt2.4(C≡CH)8](M=Cu,Ag) clusters have been studied by the TD-DFT(time-dependent density functional theory) calculations with the polarizable continuum model(PCM).The ground-and excited-state structures were optimized by the DFT(density functional theory) *** calculated structures and spectroscopic properties are in agreement with the corresponding experimental *** [Pt2.g4(C≡CH)8] clusters have two stable ground state geometries(D4 and D4h symmetry).The calculated Pt-M distances suggest only very weak *** Cu-Cu distances are larger than the van der Waals radii of two Cu atoms and the Ag-Ag distances are analogous with the sum of van der Waals radii of two Ag *** excitation,the interaction of Pt…M,Ag…Ag is strengthened,while the Cu…Cu distances are shortened but they are still larger than the sum of van der Waals radii of two Cu *** lowest-energy absorptions are at 450,365 and 375 nm and the emissions are at 611,431 and 435 nm for [Pt2.u4(C≡CH)8],[Pt2.g4(C≡CH)8](A) and(B),*** transitions are all perturbed by the Cu or Ag composition through the UV-Vis spectra region;therefore,there are not pure ILCT or MPtLCT characteristics(ILCT:intraligand charge transfer;MLCT:metal-to-ligand charge transfer) in absorptions of heteropolynuclear [Pt2.4(C≡CH)8] *** the emissions and the lowest-absorptions have different transition characteristics for each complex,the emissions should not come from the lowest-energy *** the M…M interactions in the excited state of [Pt2.g4(C≡CH)8] are augmented,the emissions of [Pt2.g4(C≡CH)8] clusters bear prominent ILCT character,which is the reason why the emission wavelengths of [Pt2.g4(C≡CH)8] have a small hypsochromic shift relative to the emission wavelength of homoleptic [Pt(C≡CH)4]2.precursor.

关键词： electronic structures luminescence behavior heteropolynuclear complexes TDDFT

Effect of solution concentration on the structured order and optical properties of short-chain polyene biomolecules

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1646-1650页

作者： OUYANG ShunLi1,2.SUN ChengLin1,2.ZHOU Mi1,2.LI DongFei2.WANG WeiWei1,2.QU GuanNan1,LI ZuoWei1,2.GAO ShuQin1 & YANG JianGe3 1 State Key Laboratory of Superhard Materials,jilin university,{2. 130012.china 2.College of Physics,jilin university,{2. 13002.,china 3 The ordnance Engineering Department,Air Force Aviation university,{2. 13002.,china State Key Laboratory of Superhard Materials Jilin University Changchun China College of Physics Jilin University Changchun China The ordnance Engineering Department Air Force Aviation University Changchun China

We have measured the Raman spectra and UV-Vis absorption spectra of linear polyene biomolecules(β-carotene and lycopene) in CS2.at low concentrations(10-6-10-10 mol/L).With decreasing concentration,all the carbon-carbon vibrations form a coherent mode in ordered β-carotene and lycopene due to extended π-conjugation that gives strong electron-phonon coupling,which leads to an anomalous experimental *** observed an extremely high Raman scattering cross section(RSCS) and the Raman activities in β-carotene and lycopene are characterized by intensive overtones and ***,the UV-Vis absorption bands become narrower.

关键词： molecular structured order Raman spectroscopy Raman scattering cross section