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THE (ｕ＋κ)-ORBIT OF ESSENTIALLY NORMAL OPERATORS AND COMPACT PERTURBATIONS OF STRONGLY IRREDUCIBLE OPERATORS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 237-248页

作者： JIYOUQING JIANGCHUNLAN WANGZONGYAO departmentofMathematics JilinUniversityChangchun130023China. departmentofMathematics JilinUniversityChangchun130023China. departmentofMathematics EastChinaUniversityofScienceandTechnologyShanghai200237＂China.

Let н be a complex, separable, infinite dimensional Hilbert space, T　ε（Ｈ）. （ｕ＋Ｋ）（T） denotes the （ｕ＋ｋ）-orbit of T, i.e., （ｕ＋ｋ）（T） = {R-1TR: R is invertible and of the form unitary plus compact}. Let be an analytic and simply connected Cauchy domain in C and n ε N. A（, n） denotes the class of operators, each of which satisfies （i） T is essentially normal; （ii） σ（T） =,　ρF（T）　∩ σ（T） = ; （iii） ind （λ-T） = -n, nul （λ-T） = 0 （λ∈Ω ）. It is proved that given T1, T2.ε A（, n） and ε > 0, there exists a compact operator K with K 2.. This result generalizes a result of P. S. Guinand and L. Marcoux [6,15]. Furthermore, the authors give a character of the norm closure of （ｕ＋Ｋ）（T）, and prove that for each T ε A（, n）, there exists a compact （SI） perturbation of T whose norm can be arbitrarily small.

关键词： Essentially normal (u+k)-orbit Compact perturbation Spectrum Strongly irreducible operator

Effect of pressure on thermostability of Fe_3B

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Chinese Science Bulletin 1997年第21期42卷 1796-1798页

作者： YAO Bin, LIN Xiaomin, LI Fushan, SU Wenhui, DING Bingzhe and HU Zhuangqi1. department of Physics, jilin University,{2., china 2. State Key Laboratory of Rapidly Solidified Non-equilibrium Alloys, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, china department of Physics Jilin University Changchun 130023 China

EFFECT of pressure on thermostability of metastable materials has been one of the importantsubjects in high-pressure research field. In the past ten odd years, much work has been donefor amorphous materials but a little for metastable crystalline materials, which indicates thatthe effect of pressure on the amorphous materials is closely related to their properties and crys-tallization mode, and is determined by two opposite influences of pressure on diffusion andnucleation, which make the thermostability of amorphous materials either increase or de-

关键词： pressure phase transition thermostability.

Synthesis and Characterization of One-dimensional and Two-Dimensional Porphyrin Polymers (Ⅰ)

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Chemical Research in Chinese Universities 2001年第2期17卷 226-227页

作者： LI Xiang-qing, WANG Xing-qiao, GUO Jing-fu, MENG He and LJU Guo-fa (department of chemistry, {2. University, changchun 13002., P. R. china) jilin Univ Dept Chem Changchun 130023 Peoples R China

A procedure for the synthesis of one-dimensional tetraaminophenylporphyrin (TAPP) was described. Quantitative infrared (IR) spectrum analysis of the monomer showed that it exhibited strong absorption at 1,62. cm-1. Results also indicated that the interaction between porphyrin macrocycles was enhanced after the metalloporphyrin linked up with the axial ligand. The degree of polymerization in [Mn(TPP)(pyz)]n was assessed using the ligand absorption rate.

关键词： Synthesis Porphyrin polymer Bipyridine Imidazole

Selection of Trypsin Inhibitors in Phage Peptide Library Using Model Pepeide Mimicking the Active Site of Trypsin

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Chemical Research in Chinese Universities 1996年第1期12卷 111-113页

作者： QI Jie FANG Rui LU Zhi-bin ZHou Hui LI Wei and SHEN Jia-cong(department of Molecular Biology, jilin University,{2., china)(department of chemistry, jilin University) jilin UNIV DEPT BIOL MOLECCHANGCHUN 130023PEOPLES R CHINA

Efficient computation for dynamic responses of systems with time-varying characteristics

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Acta Mechanica Sinica 2009年第5期25卷 699-705页

作者： Liang Ma Yudong Chen Suhuan Chen Guangwei Meng department of Mechanics, Nanling Campus,jilin University, {2. changchun, china department of Mechanics Nanling Campus Jilin University 130025 Changchun China

Based on Neumman series and epsilon-algorithm, an efficient computation for dynamic responses of systems with arbitrary time-varying characteristics is investigated. Avoiding the calculation for the inverses of the equivalent stiffness matrices in each time step, the computation effort of the proposed method is reduced compared with the full analysis of Newmark method. The validity and applications of the proposed method are illustrated by a 4-DOF spring-mass system with periodical time-varying stiffness properties and a truss structure with arbitrary time-varying lumped mass. It shows that good approximate results can be obtained by the proposed method compared with the responses obtained by the full analysis of Newmark method.

关键词： Dynamic responses Efficient computation Epsilon-algorithm Time-varying characteristics

Effect of Substituting Group on the Calculated Nonlinear Second－Order Optical Susceptibilities of Substituted Thiophene Derivatives with Quinoidlike Conformation

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Chemical Research in Chinese Universities 1995年第4期11卷 336-341页

作者： LI Zhi-ru WANG Xiao-peng PENG Ji-kang andSUN Chia-chun(department of chemistry and Institute of Theoretical chemistry,jilin University,changchun,13002.) jilin UNIV DEPT CHEMCHANGCHUN 130023PEOPLES R CHINA jilin UNIV INST THEORET CHEMCHANGCHUN 130023PEOPLES R CHINA

alculations of the nonlinear second-order optical susceptlbilities(β_(ijk))for sub- stituted tl1iophene derivative;with quinoidlike conformation are *** systetems possess small dipole moment;and large differences between dipole mo- ments of ground and first-excited *** optimizations of the molecules investigated were carried out using AM 1 *** calculations were performed using INDO/CI method comboned with a sum-over-states expression for β_(jik). The calculated results sbw that the second-order susceptibility is a function of the na- ture and location of substituents and is larger for disubstituted molecules than monosubstituted molecules. Bipolymeric thiophenemetmne with NH_2.NO_2.groups was calctilated to have a β_μof 79. 92. × 10￣(-30) esu. It was found that the NH_2.and NO_2.groups in above disubstituted molecules are pull-pull groups in ground states,but are usual push-pull groups in the first excited states.

关键词： Nonlinear second-order optical susceptibility INDO/CI,Substituted thiophene derivatives

DYNAMIC OPTIMIZATION FOR UNCERTAIN STRUCTURES USING INTERVAL METHOD

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Acta Mechanica Solida Sinica 2003年第2期16卷 141-146页

作者： Chen Suhuan Wu Jie Liu Chun (department of Mechanics,jilin University,{2. 13002.,china) departmentofMechanics JilinUniversityChangchun130025China

An interval optimization method for the dynamic response of structures with inter- val parameters is *** matrices of structures with interval parameters are ***- bining the interval extension with the perturbation,the method for interval dynamic response analysis is *** interval optimization problem is transformed into a corresponding de- terministic *** the mean values and the uncertainties of the interval parameters can be elected design variables,more information of the optimization results can be obtained by the present method than that obtained by the deterministic *** present method is implemented for a truss *** numerical results show that the method is effective.

关键词： interval optimization interval parameter structure interval extension of function dynamic interval response

The Synthesis of Single Crystals of Manganese Aluminophosphate Molecular Sieve and Studies on Their Properties

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Chemical Research in Chinese Universities 1989年第1期5卷 1-7页

作者： Han Shuyun and Zhou Jianrong(department of chemistry, {2. University, changchun)

Single crystals of the molecular sieve, MnAPO-5, were synthesized by hydrothermal synthesis in the presence of fluoride ions. It was shown by X-ray diffraction, infrared spectroscopy, electron paramagnetic resonance spectroscopy, electron probe analysis and chemical composition analysis that the structure of MnAPO-5 is of the A1PO-5 type, and manganese(Ⅱ) is incorporated into the framework. Adsorption properties, thermal stability and surface acidity were also investigated.

关键词： Single crystal Synthesis Molecular sieve

Nanostructured Columns from Self-assemblyof Complementary Molecular Components

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Chemical Research in Chinese Universities 2001年第2期17卷 193-197页

作者： YANG Wen-sheng ,YANG Bai-quan, JIANG Yue-shun and LI Tie-jin (department of chemistry, {2. University, changchun, 13002., P. R. china) LIU Ya-Juan (Institute of Information Technology, {2. Agriculture University, changchun, 130118, P. R. china) jilin Univ Dept Chem Changchun 130023 Peoples R China jilin Agr Univ Inst Informat Technol Changchun 130118 Peoples R China

Nanostructured columns with a length about several tens of micrometer and a diameter of about 80 nm were obtained by molecular recognition directed self-assembly of a pair of comple- mentary molecular components, 4-amino-2., 6-didodecylamino-1 , 3, 5-triazine(M) and 5- (4-dode- cyloxybenzylidene )-(1H, 3H)-2. 4, 6-pyrimidinetrione (B) in chloroform. In this system, with positive cooperativity, π-aromatic stacking and van der Waals interactions as well as hydrogen bonds cause the formation of the nanocolumns.

关键词： Nanocolumn Self-assembly π-aromatic stacking Molecular recognition