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science china Chemistry 2007年第5期50卷 599-606页

作者： ZHOU Xin1, PAN QingJiang2. LI MingXia1,2. ZHANG HongXing1 & Tang AuChin1 1 State Key laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin university, Changchun 13002.,{2. 2.school of Chemistry and materials science, heilongjiang university, harbin 150080,{2. State Key laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun China school of Chemistry and materials {2. Heilongjiang University Harbin China

We have studied the ground and excited states of the three dendriticpolynuclear Pt(ll) complexes 1-[Cl(PH3)2.tC ident to C]-3,5-[HC ident to C]C6H3 (1),1,3-[CI(PH3)2.tCident to C]2.5-[HC ident to C]C6H3 (2.,and 1,3,5-[CI(PH3)2.PtC ident to C]3C6H3 (3),by using theB3LYP and UB3LYP methods,*** approach with the PCM model was performed to predict theemission spectra properties of 1-3 in CH2.l2.*** first predicted the excited-stategeometries for the three *** the change of the number of Pt(ll) atom,1-3 show thedifferent geometry structures in both the ground and excited states;furthermore,the increase of themetal density from 1 to 3 results in the red shift of the lowest-energy emissions along *** luminescent properties of 1 are somewhat different from those of 2.and *** emissionproperties of 2.and 3 are richer than *** conclusion can give a good support for designing thehigh efficient luminescent materials.

关键词： excited state luminescence dendritic platinum(ll) complexes DFT TDDFT

Theoretical studies on Ru(fppz)_2.CO)L (L=N-heterocyclic ligand):Electronic structure,absorption,phosphorescence,and solvatochromism

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science china Chemistry 2008年第12期51卷 1211-1220页

作者： LIU Tao1, ZHOU Xin1, BAI FuQuan1, ZHANG JianPo1, XIA BaoHui1,2. PAN QingJiang3 & ZHANG HongXing1 1 State Key laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin university, Changchun 13002.,{2. 2.College of Chemistry, Jilin university, Changchun 13002.,{2. 3 laboratory of physical Chemistry, school of Chemistry and materials science, heilongjiang university, harbin 150080,{2. State Key laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun China College of Chemistry Jilin University Changchun China laboratory of physical Chemistry School of Chemistry and Materials Science Heilongjiang University Harbin China

A series of ruthenium(II) complexes Ru(fppz)2.CO)L [fppz = 3-trifluoromethyl-5(2.pyridyl)pyrazole; L = pyridine (1), 4-dimethylaminopyridine (2., 4-cyanopyridine (3)] were designed and investigated theo-retically to explore their electronic structures, absorption, and emissions as well as the solvatochrom-ism. The singlet ground state and triplet excited state geometries were fully optimized at the B3LYP/LANL2.Z and CIS/LANL2.Z level, respectively. The HOMO of 1-3 is composed of dyz(Ru) atom and π(fppz). The LUMO of 1 and 2.is dominantly contributed by π*(fppz) orbital, but that of 3 is con-tributed by π*(L). Absorption and phosphorescence in vacuo, C6H12. and CH3CN media were calculated using the TD-DFT level of theory with the PCM model based on the optimized ground and excited state geometries, respectively. The lowest-lying absorption of 1 and 2.at 387 and 391 nm is attributed to {[dyz(Ru) + π(fppz)] → [π*(fppz)]} transition, but that of 3 at 479 nm is assigned to {[dyz(Ru) + π(fppz)] → [π*(L)]} transition. The phosphorescence of 1 and 2.at 436 and 438 nm originates from 3{[dyz(Ru) + π(fppz)] [π*(fppz)]} excited state, while that of 3 at 606 nm is from 3{[dyz(Ru) + π(fppz)] [π*(L)]} excited state. The calculation results showed that the absorption and emission transition character can be changed from MLCT/ILCT to MLCT/LLCT transition by altering the substituent on the L ligand. The phosphorescence of 1 and 2.does not have solvatochromism, but that of 3 at 606 nm (vacuo), 584 nm (C6H12., and 541 nm (CH3CN) is strongly dependent on the solvent polarity, so introducing elec-tron-withdrawing group on ligand L will induce remarkable solvatochromism.

关键词： ruthenium complex DFT phosphorescence solvatochromism

Interaction of cellular-localized signature modules in response to prostate cancer

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Progress in Natural science:materials International 2007年第11期17卷 1368-1375页

作者： Zhu Jing1, Guo Zheng1,2. Zhang Min2. Yang Da2. Wang Jing2.and Wang Chenguang2.1. school of Life science and Bioinformatics Centre, {2. of Electronic science and Technology of china, Chengdu 610054, china 2. Department of Bioinformatics, Bio-Pharmaceutical Key laboratory of heilongjiang Province, harbin Medical {2., harbin 150081, china) school of Life science and Bioinformatics Centre University of Electronic Science and Technology of China Chengdu 610054 China

Rapid progress in high-throughput biotechnologies (e.g. microarrays) and exponential accumulation of gene functional knowledge makes it promising for systematic understanding of complex human diseases at the functional modules level. Current modular categorizations can be defined and selected more specifically and precisely in terms of both biological processes and cellular locations, aiming at uncovering the modular molecular networks highly relevant to cancers. Based on Gene Ontology, we identifed the functional modules enriched with differentially expressed genes and characterized by biological processes and specific cellular locations. Then, according to the ranking of the disease discriminating abilities of the pre-selected functional modules, we further defined and filtered signature modules which have higher relevance to the cancer under study. Applications of the proposed method to the analysis of a prostate cancer dataset revealed insightful biological modules.

关键词： microarray analysis Gene Ontology classification analysis cellular location functional module

Structures and stability of isomers of[C,N,N,P]system

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science china Chemistry 2005年第5期48卷 415-423页

作者： KAN Wei1,2. ZHONG Hua1, YU Haitao1, FU Honggang1,3 & SUN Jiazhong1,3 1. school of Chemistry and materials {2., heilongjiang university, harbin 150080, china 2. school of Chemistry and Chemical Engineering, Qiqihar university, Qiqihar 161006, china 3. State Key laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin university, Changchun 13002., china school of Chemistry and materials {2. Heilongjiang University Harbin China school of Chemistry and Chemical Engineering Qiqihar University Qiqihar China Jilin university Changchun China

Nine isomers, twenty transition states, and some relative dissociation fragments of [C,N,N,P] system were located at the B3LYP/6-311G(d) and QCISD(t)/6-311+G(2.f) (single-point) levels of theory, and the isomerization, structures, and stability of these obtained isomers were suggested. The results indicate that four nonlinear chainlike isomers NCNP, NCPN, CNPN, and CNNP with 2.′ electronic state are kinetically stable. Other isomers are kinetically unstable to-wards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, calculated vibrational frequencies, rotational constants, dipole moments, the first adiabatic ionization energies, and adiabatic electron affinities of the four isomers may provide some theoretical information that is helpful for identifying their existence in future laboratory and interstellar investigations. The results are also compared with [Si,N,N,P] system.

关键词： potential energy surface, [C,N,N,P] system, isomerization, kinetic stability.

Ln_2.O_4 cathode materials for solid oxide fuel cells

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science china Chemistry 2011年第6期54卷 898-910页

作者： ZHAO Hui, LI Qiang & SUN LiPing Key laboratory of Functional Inorganic Material Chemistry, Ministry of Education school of Chemistry and {2. science, heilongjiang university, harbin 150080, china Key laboratory of Functional Inorganic Material Chemistry Ministry of Education school of Chemistry and materials {2. Heilongjiang University Harbin China

One of the major challenges to develop "intermediate temperature" solid oxide fuel cells is finding a novel cathode material, which can meet the following requirements: (1) high electronic conductivity; (2. chemical compatibility with the electrolyte; (3) a matched thermal expansion coefficient (TEC); (4) stability in a wide range of oxygen partial pressure; and (5) high catalytic activity for the oxygen reduction reaction (ORR). In this short review, a survey of these requirements for K2.iF4-type material with the formula Ln2.O4, Ln = La, Pr, Nd, Sm; M = Ni, Cu, Fe, Co, Mn, is presented. The composition-dependent TEC, electrical conductivity and oxygen transport property are considered. The Ln2.O4 materials exhibit improved chemical stability and compatibility with most of the traditional electrolytes. The complete fuel cells integrated with Ln2.O4 materials as cathodes show promising results. Furthermore, these materials are considered as cathodes of protonic ceramic fuel cell (PCFC), and/or anodes of high temperature steam electrolysis (HTSE). First results show excellent performances. The versatility of these Ln2.O4 materials is explained on the basis of structural features and the ability to accommodate oxygen non-stoichiometry.

关键词： intermediate temperature solid oxide fuel cells (ITSOFCs) cathode K2.iF4-type structure oxygen non-stoichiometry

A computer simulation of nucleation and growth of thin films

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science china(Physics,Mechanics & Astronomy) 2004年第4期47卷 442-451页

作者： ZHENG Xiaoping1,ZHANG Peifeng2.HE Deyan2.LIU Jun2. MA Jiantai3 1. Key laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong university, Lanzhou 730070,{2. 2. school of physical science and Technology, Lanzhou university, Lanzhou 730000,{2. 3. school of Chemistry and Chemistry Engineering, Lanzhou university, Lanzhou 730000,{2. Key laboratory of Opto-Electronic Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou China school of physical {2. and Technology Lanzhou University Lanzhou China school of Chemistry and Chemistry Engineering Lanzhou University Lanzhou China

A three-dimensional kinetic Monte Carlo technique has been developed for simulating the nucleation and growth of thin films. This model involves incident atom attachment, surface diffusion of the atoms on the growing surface and atom detachment from the growing surface. It takes some new effects into account, such as a significant improvement in calculation of activation energy for the atom diffusion, which renders the model more reasonable. In addition three optimum temperatures and the consistency of their dependence on deposition rate have been found out; the dependence of the surface roughness and relative density on the deposition rate has been discussed; and the approximation of freezing neighbour atoms and periodic boundary conditions has been applied.

关键词： Monte Carlo, thin film, nucleation, surface roughness, relative density.

Surface Nanocrystallization of Magnesium Alloy AZ91D by High-Energy Shot Peening

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Journal of Wuhan university of Technology(materials {2.) 2009年第4期24卷 515-519页

作者：张津 school of materials {2. & Engineering University of Science and Technology Beijing College of materials science & Engineering Chongqing University of Technology

High-energy shot peening （HESP）, a method to produce severe plastic deformation by high velocity flying balls, was applied on die cast magnesium alloy AZ91D. Effects of surface nanocrystallization by HESP and heat treatment at different temperatures were investigated. The mi- crostructure evolution was conducted using X-ray diffraction （XRD） and field emission scanning electronic microscopy （FESEM）. The hardness was measured by microhardness tester. The experimental results show that surface nanocrystrallization of AZ91D obtained by HESP would lead to the increase of microhardness. Low temperature heated at 100℃ for 1 h do not change the property obviously. However, both the microstructure and microhardness vary greatly after heat treatment at 400℃ for 1 h.

关键词： AZ91 D surface nanocrystallization HESP microhardnss corrosion resistance

Phase transition in the Zr_(60)Al_(15)Ni_(2.) bulk metallic glass subjected to rolling at room temperature

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science china(Technological sciences) 2006年第6期49卷 655-662页

作者： YAN Zhijie1, 2. LI Jinfu1, ZHOU Yaohe1 & WU Yanqing3 1. State Key laboratory of Metal Matrix Composites, school of {2. science and Engineering, Shanghai Jiao Tong university, Shanghai 2.0030, china 2. school of {2. science and Engineering, Taiyuan university of science and Technology, Taiyuan 03002., china 3. school of Environmental science and Engineering, Shanghai Jiao Tong university, Shanghai 2.0030, china State Key laboratory of Metal Matrix Composites School of Materials Science and Engineering school of materials {2. and Engineering Taiyuan University of Science and Technology

The microstructure evolution of the Zr60Al15Ni2. metallic glass during rolling at room temperature is investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC); high-resolution transmission electron microscopy (HREM). The results show that the values of full width at half maximum (FWHM) of the XRD patterns; exothermic enthalpy ΔH of DSC plots do not monotonically change with the variation of deformation degrees . As is not large than 2.%, the values of FWHM; ΔH are lower than that of the as-cast state. When reaches 30%, the values of FWHM; ΔH become larger than that of the as-cast state, while their values begin to decrease again as reaches about 85%. These results indicate that the reversible transitions between ordered; disordered atomic configurations occur during rolling, which is further verified by the HREM images. The reversible phase transition can be explained by the competition between the diffusion controlled reordering; shear-induced disordering during rolling.

关键词： metallic glasses, plastic deformation, phase transformations, shear bands.

Magnetron sputtering synthesis of large area well-ordered boron nanowire arrays

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science china(Physics,Mechanics & Astronomy) 2004年第4期47卷 403-415页

作者： CAO Limin1,2. ZHANG Ze2.& WANG Wenkui1,2.1. Key laboratory of Metastable materials {2. and Technology and College of materials {2. and Engineering, Yanshan university, Qinhuangdao 066004, china 2. Institute of Physics, Chinese Academy of {2.s, Beijing 100080, china Key laboratory of Metastable materials {2. and Technology and College of materials {2. and Engineering Yanshan University Qinhuangdao China Institute of Physics Chinese Academy of Sciences Beijing China

One-dimensionally nanostructured materials, such as nanowires and nanotubes, are the smallest dimensional structures for efficient transport of electrons and excitons, and are therefore critical building blocks for nanoscale electronic and mechanical devices. In this paper, boron nanowires with uniform diameters from 2. to 80 nm were synthesized by radio-frequency magnetron sputtering of pure boron powder and B2.3 powder mixtures in argon atmosphere. The boron nanowires produced stand vertically on the substrate surface to form well-ordered arrays over large areas with self- organized arrangements without involvement of any template and patterned catalyst. The high-density boron nanowires are parallel to each other and well distributed, forming highly ordered and uniform arrays. A more interesting and unique feature of the boron nanowires is that most of their tips are flat rather than hemispherical in morphologies. Detailed studies on its structure and composition indicate that boron nanowires are amorphous. Boron nanowire appears as a new member in the family of one-dimensional nanostructures. Considering the unique properties of boron-rich solids and other nanostructures, it is reasonable to expect that the boron nanowires will display some exceptional and interesting properties. A vapor-cluster-solid (VCS) mechanism was proposed to explain the growth of boron nanowires based on our experimental observations.

关键词： boron nanowires, magnetron sputtering, arrays, self-assembly.

Thermodynamic Analysis of the Preparation Process of EB-PVD SiC Coating

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Journal of Wuhan university of Technology(materials {2.) 2009年第3期24卷 363-366页

作者：易剑 school of Mechatronics Engineering Taizhou University Laser Processing Center Tianjin Polytechnic University Center for Composite materials Harbin Institute of Technology

The process of preparing SiC coating by electron beam-physical vapor deposition （EB-PVD） was discussed from viewpoint of thermodynamis. Results show that within the temperature range of 2.700-3 300 K, the ratio of SiC in the SiC coating doesn＇t change much and keeps around 0.7. Purity of the as-deposited SiC coating is not high. To improve the purity of the SiC coating, the SiC ingot is required to not be, necessary in full density but be fine-grained.

关键词： thermodynamics SiC coating EB-PVD ratio of SiC purity