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Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

Science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2, CUI Yuezhi3. HUANG Zhenli4, XUE Gang1 & YU Wentao1 1. State Key Laboratory of Crystal Materials, shandong University, jinan 2.01.0, china 2. School of Information Science and {3., shandong University, jinan 2.01.0, china 3. department of chemical engineering, light industry college of shandong, jinan 2.01.0, china 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong University of Science and Technology, Wuhan 43.074, china 1. State Key Laboratory of Crystal Materials Shandong University 250100 Jinan China 2. School of Information Science and engineering Shandong University 250100 Jinan China 3. department of chemical engineering Light Industry College of Shandong 250100 Jinan China 4. Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4-dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2,4-dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2-methyl-4,6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064 nm fundamental laser, NEt-1 powder crystals radiate a 2-order harmonic light with an intensity 46.8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21 space group. Its powder crystals exhibit a 2-order harmonic intensity 46.2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

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The Isomeric Structures of H_2GeLiF, the Prototype Germylenoid

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Chinese chemical Letters 1999年第6期10卷 511-514页

作者： Hua Yu QIU Wan Yong MA Guan Bin LI Cong Hao DENG (department of chemical engineering. {3. Institute of light industry. jinan 2.01.0 Institute of Theoretical Chemistry. {3. University, jinan 2.01.0) shandong Inst light Ind Dept Chem Engn Jinan 250100 Peoples R China shandong Univ Inst Theoret Chem Jinan 250100 Peoples R China

The structures of four isomeric forms of the model germylenoid, H2GeLiF. have been examined by ah initio MO theory. The most stable structure is suggested to be the p-complex *** other three species. three-membered ring 2, δ-complex 3.and tetrahedron 4. are also local minima on the potential energy surface. but are higher in energy.

关键词： Germylenoid p-complex ab initio

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Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2, ZHANG Jiao qiang 3. (1. department of Chemistry,Northwest University, Xi′an 710065, china 2. department of Chemistry and {3. engineering, Baoji college of Arts and Science, Baoji 721007, china 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

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Investigation on the Surface Coating of Grinding Balls

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Rare Metals 2001年第4期20卷 259-264页

作者： Chengguo Wang1 Yujun Bai1.2 1) college of Materials Science and engineering, shandong University, {3. 250061, china 2) Mechanical department. shandong University of Science and Technology. {3. 25003., china shandong Univ Coll Mat Sci & Engn Jinan 250061 Peoples R China Shanghai Univ Sci & Technol Dept Mech Jinan 250031 Peoples R China

The surface coating of grinding balls was investigated experimentally. The results show that a coating may form on the surface of grinding balls when Cr or Al powders are subjected to ball grinding. The plastic deformation of the ball surface plays an important role during the coating formation, and the strong binding force between the powders and the balls is a necessary pre-condition. The thickness of coating increases with the plasticity of the powders and the balls. Annealing the balls with coating will result in an obvious diffusion of the elements in the bonding zone of interface.

关键词： coating ball grinding plastic deformation

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OSCILLATION　FREQUENCY　THEORY　OF　A　PIEZOELECTRIC　SENSOR　INLIQUID　PHASE　WITH　TWO　SEPARATED－ELECTRODES

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Chinese chemical Letters 1996年第2期7卷 169-172页

作者： Da Zhong SHEN Ze Chang LIU Qing KANG Jind Tian HU(Chemistry college, shandong University, jinan, {3.)(chemical engineering department, jinan Branch of shandong Institute of Mining and Technology, jinan, 28003.) shandong UNIV CHEM COLLJINAN 250100PEOPLES R CHINA SHANGHAI INST MIN & TECHNOL DEPT CHEM ENGNJINAN 250031PEOPLES R CHINA

In this paper, an oscillation frequency equation for a pizoelectric sensor with two separated-electrodes is theoretically derived and experimentally verified. The correlatione of the oscillation frequency and the liqu... 详细信息

关键词： SENSOR FREQUENCY INLIQUID OF OSCILLATION PHASE PIEZOELECTRIC ELECTRODES SEPARATED THEORY

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The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 667-675页

作者： GE Meihua1, ZHANG Yanhui1, WANG Dehua2, DU Mengli3.& LIN Shenglu1 1. college of Physics and Electronics, shandong Normal University, jinan 250014,{3. 2. department of Mathematics and Physics, shandong Institute of Architecture and engineering, jinan 250014,{3. 3. Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080,{3. 1. college of Physics and Electronics Shandong Normal University 250014 Jinan China 2. department of Mathematics and Physics Shandong Institute of Architecture and Engineering 250014 Jinan China 3. Institute of Theoretical Physics Chinese Academy of Sciences 100080 Beijing China

The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 20. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface.

关键词： Rydberg hydrogen atom, van der Waals interaction, Poincaré surface of section, closed orbit theory, chaos.

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The extension of the first main theorem for π-blocks

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Science china Mathematics 2006年第5期49卷 620-625页

作者： HAI Jinke department of Mathematics, Qingdao University, Qingdao 266071, china college of mathematics ,{3. University, jinan 2.01.0, china department of Mathematics Qingdao University Qingdao 266071 China college of mathematics Shandong University Jian 250100 China

Let π be a set of primes and G a π-separable group. Isaacs defines the Bπ characters, which can be viewed as the "π-modular" characters in G, such that the Bp′ characters form a set of canonical lifts for the p-modular characters. By using Isaacs' work, Slattery has developed some Brauer's ideals of p-blocks to the π-blocks of a finite π-separable group, generalizing Brauer's three main theorems to the π-blocks. In this paper, depending on Isaacs' and Slattery's work, we will extend the first main theorem for π-blocks.

关键词： π-block, π-separable group, π-regular classes, defect group.

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Sensitized Luminescence of Rare Earths

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chemical Research in Chinese Universities 1996年第1期12卷 10-15页

作者： SI Zhi-kun HU Jing-tian JIANG Wei and ZHU Gui-yun(department of Chemistry, shandong University, jinan, {3.)LI Shu-hua(department of Basic Courses, shandong Institute of light industry, jinan, {3.) shandong UNIV DEPT CHEMJINAN 250100PEOPLES R CHINA shandong INST light IND DEPT BASIC COURSESJINAN 250100PEOPLES R CHINA

The enhancement effect on the fluorescence intensities of an Eu3. (or/and Sm3. )-thenoyltrifluoroacetone (TTA )-dibenzo-18-crown-6 (18-C-6 ) system and Eu 3. (or /and Sm3. ) -benzoyltrifluoroacetone (BTA )-cetyltrimethylammonium bromide (CTMAB) system by dysprosium has been studied. In the presence of enhancing ions, the fluorescence intensities of the above systems were enhanced by a factor of about 40-150, respectively. The above systems were used for the determination of europlum or/and samarium in rare earths oxides and gave satisfactory results.

关键词： Sensitized luminescence Rare earths Fluorescence

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Comparison of Structure and Properties among Various PAN Fibers for Carbon Fibers

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Journal of Materials Science & Technology 2005年第3期21卷 376-380页

作者： Dongxin HE, Chengguo WANG, Yujun BAI and Bo ZHU college of Materials Science and engineering, shandong University, {3. 250061, china college of Materials Science and engineering Shandong University Jinan 250061 China

To find out the high-quality polyacrylonitrile (PAN) fibers, some differences are sought by comparing domestic PAN fibers with the foreign ones. X-ray diffractometer (XRD), transmission electron microscope (TEM), Fourier transform infrared (FT-IR) spectrometer, elemental analyzer, tensile-testing machine and high-temperature differential scanning calorimeter (DSC) are used to characterize the individual microstructure, chemical structure, elemental content, mechanical properties and thermal properties. It is found that high-quality PAN fibers have high density, lower titre, higher or adequate tensile strength, and they also have better conglomeration structure, smaller crystal dimension with dispersive distribution, less microvoids and flaws.

关键词： Polyacrylonitrile (PAN) fiber Carbon fiber Structure Properties

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Lattice dynamical simulation of methane hydrate

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Journal of Natural Gas Chemistry 2010年第1期19卷 43-46页

作者： Lin Wang, Shunle Dong Physics department, college of Information Science and engineering, Ocean University of{3., Qingdao 266100, shandong,{3. [a] Physics department College of Information Science and Engineering Ocean University of China Qingdao 266100 Shandong China

INS （Inelastic Neutron Scattering） spectrum of methane hydrate was measured on MARI （a direct-geometry chopper spectrometer） at Ruther-ford Appleton Laboratory, UK. Compared with ice Ih, it is found that the whole spectrum of methane hydrate moves toward high-energy by about 1.5 meV. Using lattice dynamical （LD） technique, computer simulations of methane hydrate were carried out. In the simulations, four potential models （BE TIP3., TIP4P, MCY） were employed to calculate the phonon density of states （PDOS）. Comparing the calculated PDOS spectrum with the experimental spectrum, it is found that BF, TIP4P, and TIP3. potential lattices give out well-separated translational and librational bands while MCY potential lattice is unstable to do so and this model is not suitable to describe hydrate system.

关键词： methane hydrate inelastic neutron scattering lattice dynamical simulation

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