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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 250100, china 2. School of Information Science and {3., shandong University, jinan 250100, china 3. Department of chemical {3., light industry college of shandong, jinan 250100, china 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong University of Science and Technology, Wuhan 4.0}074. china State Key Laboratory of Crystal Materials Shandong University Jinan China School of Information Science and engineering Shandong University Jinan China Department of chemical engineering Light Industry College of Shandong Jinan China Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 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 4..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 4..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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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.)({4. engineering Department, jinan Branch of shandong Institute of Mining and Technology, jinan, 28003.) Chemistry college Shandong University Jinan 250100 chemical engineering Department Jinan Branch Shandong Institute of Mining and Technology Jinan 250031

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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Theoretical Studies on the Structures and Reactions of Halocarbenoids(Ⅰ)Structures and Stability of Chlorocarbenoid CHCl_2

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chemical Research in Chinese Universities 1997年第3期13卷 256-261页

作者： Li LI Ji-hai, FENG Sheng-yu,Liu Wei (chemical college,shandong University,{3., {4.) shandong UNIV CHEM COLLJINAN 250100PEOPLES R CHINA

The chlorocarbenoid , CHCl2Li , was studied by means of ab initio molecular or- bital theory. Three equilibrium structures and two isomerization transition states were located. The calculations showed that the three-membered ring structure is the most stable. The 'classical tetrahedral' structure is not the local minimum on the potential energy surface.

关键词： Chlorocarbenoid isomeric structure Ab initio molecular orbital calcu- lation

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Preparation and microstructure of CuO-CoO-MnO/SiO2 nanocomposite aerogels and xerogels as catalyst carriers

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Progress in Natural Science:Materials International 2011年第4期21卷 330-335页

作者： Yue-qing ZHAO~1,Ying-hua LIANG~2,Xi-zhe ZHAO~3.Qian-yi JIA~4.Hong-sheng LI~4.1.college of light industry,Hebei United University,Tangshan 063.00,{3. 2.college of chemical engineering,Hebei United University,Tangshan 063.09,{3. 3.college of Printing and Packaging engineering,Beijing Institute of Graphic Communication,Beijing 102600,{3. 4.college of Materials Science and engineering,Hebei United University,Tangshan 063.09,{3. college of light industry Hebei United University Tangshan 063000 China college of chemical engineering Hebei United University Tangshan 063009 China college of Printing and Packaging engineering Beijing Institute of Graphic Communication Beijing 102600 China college of Materials Science and engineering Hebei United University Tangshan 063009 China

CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were prepared using tetraethyl orthosilicate（TEOS） as Si source,and aqueous solution of Cu,Co and Mn acetates as the precursor via sol-gel process,CO2supercritical drying（SCD） technique or ambient pressure drying *** microstructure of the CuO-CoO-MnO/SiO2nanocomposite aerogels and xerogels were characterized by field emission scanning electron microscopy（FE-SEM）,transmission electron microscopy（TEM） and X-ray diffraction（XRD）.The specific surface area,pore size and pore size distribution of the nanocomposite aerogels and xerogels were determined by the Brunauer-Emmett-Teller（BET） *** results showed that CuO-CoO-MnO/SiO2nanocomposite aerogels are porous,with a pore size distribution of 2-50 nm,an average pore size of 19.4.nm,a specific surface area of 3.4.9 m2/g and a particle size distribution of 10-150 nm,whereas the pore size distribution of CuO-CoO-MnO/SiO2composite xerogels is 1.7-128.6 nm,the average pore size is only 9.9 nm,the specific surface area is only 99.1 m2/g,and the particle size distribution is 100-500 *** structure of CuO-CoO-MnO/SiO2nanocomposite aerogels is favorable to increase the loading of catalysts.

关键词： composite aerogel composite xerogel catalyst carrier preparation microstructure

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Oscillation Conditions for An Electrode-separated Piezoelectric Sensor in Electrolyte Solution

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chemical Research in Chinese Universities 1996年第1期12卷 22-31页

作者： SHEN Da-zhong(Chemistry college, shandong University, jinan, {3.)KANG Qi({4. engineering Department, jinan Branch of shandong Institute of Mining and Technology, jinan, 25003. )YAO Shou-zhuo(New Material Institute, Hunan University, Changsha, 4.00 shandong UNIV COLL CHEMJINAN 250100PEOPLES R CHINA INST MIN & TECHNOL DEPT CHEM ENGNJINAN 250031PEOPLES R CHINA HUNAN UNIV NEW MAT INSTCHANGSHA 410082PEOPLES R CHINA

Based on the needs of the oscillation equation and frequency stability, three oscillation conditions are proposed and have been experimentally verified for an electrode-separated piezoelectric sensor (ESPS ) in electrolyte solutions. The present paper covers the dependence of the minimum cell constant needed for the ESPS on solution conductivity. The oscillation conditions of the classical liquid piezoelectric sensor are discussed. The 'cease-to-oscillate' frequencies of the ESPS were measured.

关键词： Piezoelectric sensor Quartz crystal Cell constant Conductivity

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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2)molecule

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2, SUN Weiguo1, HOU Shilin3.& FENG Hao4.1. Institute of Physics, college of chemical engineering, Sichuan University, Chengdu 610065,{3. 2. Institute of Theoretical Physics, Xihua Normal University, Nanchong 63.002,{3. 3. Department of Physics,{3. Oceanography University, Qingdao 266003.{3. 4. college of Physics, Sichuan University, Chengdu 610065,{3. Institute of Physics College of Chemical Engineering Sichuan University Chengdu China Institute of Theoretical Physics Xihua Normal University Nanchong China Department of Physics China Oceanography University Qingdao China college of Physics Sichuan University Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2 molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

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Investigation on the Thermostability of Germanium and Elimination of Chloride and *** on Germanium in Graphite Furnace Atomic Absorption Spectrometry

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Chinese chemical Letters 1999年第4期10卷 333-334页

作者： Su Ping FENG Bo ZHOU Li Rong ZENG Rong Li CHEN (Experimental Center, shandong University, jinan 250100)(college of Chemistry, shandong University, jinan 250100) Experimental Center Shandong University Jinan 250100 China college of Chemistry Shandong University Jinan 250100 China

The thermostability and the interference-resisting property of germanium (Ge) in graphite furnace atomic absorption spectrometry (***) were increased remarkably when palladium and lithium nitrates were used as complex... 详细信息

关键词： GF.AAS germanium eliminate interference

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STUDY ON POLYMERIZATION OF OILLESS ALKYD RESIN WITH PHENYLTRIETHOXYSILANE

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Chinese chemical Letters 1992年第8期3卷 615-618页

作者： Shi Tai WANG Qing Si ZHANG Wan Yong MA shandong college of light {3.,{4.,250100

Oilless alkyd resin modified with the silicoorganic compounds has been obtained successfully by *** appropriate proportion of silicoorganic compounds,the polymerized product has higher hardness and lustre than that of... 详细信息

关键词： high STUDY ON POLYMERIZATION OF OILLESS ALKYD RESIN WITH PHENYLTRIETHOXYSILANE than

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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,{4. 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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Performance of Hyperspherical Harmonic Expansionon the Low-lying P and D States of Helium Atom

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chemical Research in Chinese Universities 2000年第4期16卷 351-355页

作者： WANG Yi-xuan, ZHUANG Bing-you and LIU Cheng-bu (School of Chemistry, shandong University, jinan 250100, china) (Department of Chemistry, Weifang {3., Weifang 26104.3} china) 山东大学山东济南 250100 潍坊高等专科学校山东潍坊 2610043

The wave functions of the n1,3. (n=2, 3. 4. and the n 1,3. (n=3. 4. 5 ) low-lying states of the helium atom are expanded into the complete sets of the symmetrically adapted basis functions from hyperspherical harmonic functions in the angle part and of generalized Laguerre functions in the radial part respectively, and are then augmented by the simplest type of Jastrow correlation factor to incorporate electron-nucleus cusp only. The excellent agreement between the present nonrelativistic eigen-energies and those from the sophisticated configuration interaction (CI) method for the examined states indicates that the hyperspherical harmonic method can also be applied to the P and the D excited states of the helium atom.

关键词： Hyperspherical coordinate Helium atom Excited state

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