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Synthesis and Crystal Structure of [Cis-1,10phenanthroline-palladium(Ⅱ)(THF)_2]dinitrate (THF = Tetrahydrofuran)

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Chinese Journal of Structural Chemistry 2003年第5期22卷 547-549页

作者： HUANG Hui YU Shu-Yan② (State key laboratory of polymer Physics and Chemistry, Joint laboratory of polymer Science and materials, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100080, China) Institute of Chemistry The Chinese Academy of Sciences State Key Laborator6y of Polymer Physics and Chemistry Joint Laboratory of Polymer Science and Materials CAS 北京 100080

A mononuclear complex, cis-1,10-phenanthroline-palladium(Ⅱ)(THF)2]dinitrate (THF = tetrahydrofuran) [Pd(C10H8N2)(C4H8O)2](NO3)2 1, has been prepared and structurally characterized by single-crystal X-ray diffraction. The crystal belongs to monoclinic system, space group P21/c with a = 7.881(1), b = 27.371(3), c = 10.178(1) ? ?= 103.313(3)? V = 2136.5(4) 3, Mr = 554.83, Dc = 1.725 g/cm3, Z = 4, F(000) = 1128 and (MoK) = 0.926 mm-1. The structure was refined to R = 0.0678 and wR = 0.1651 for 1687 observed reflections with I > 2(I). It is revealed that the central Pd(Ⅱ) ion in the title complex is bonded to two THF and two phenanthroline molecules in a cis-configuration to form the coordination geometry, deviating slightly from the square plane.

关键词： crystal structure Pd(Ⅱ) complex 1,10-phenanthroline

Synthesis of a novel benzoxazine containing benzoxazole structure

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Chinese Chemical Letters 2010年第5期21卷 558-562页

作者： Po Yang,Yi Gu State key laboratory of polymer materials Engineering,College of polymer Science and Engineering, Sichuan University,Chengdu 610065,China State key laboratory of polymer materials Engineering College of Polymer Science and Engineering Sichuan University Chengdu 610065 China

A high-purity benzoxazine（Boz-BOA） containing benzoxazole structure was successfully synthesized by three-step synthetic method using 2-（4-aminophenyl）-1H-benzoxazole-5-amine（BOA） and *** structure of Boz-BOA was confirmed by FTIR and;H NMR *** DSC was utilized to probe the curing behavior of Boz-BOA and exhibited a narrow melting peak and curing exothermic peak.

关键词： Benzoxazine Benzoxazole Synthesis Characterization

Advances in Thermionic Cathode of Tungsten and Molybdenum

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Rare Metals 2001年第3期20卷 137-141页

作者： Jinshu Wang,Meiling Zhou, Tieyong Zuo, Juan Liu, Jiuxing zhang, Zuoren Nie The key laboratory of Advanced functional materials, Ministry of Education, School of materials Scence and Engineering, Beijing Polytechnic University, Beijing 100022, China 北京工业大学教育部新型功能材料重点实验室北京 100022.

Several kinds of tungsten thermonic cathodes have been introduced. As a promising alternative for thoriated tungsten, rare earth doped molybdenum cathode has been studied. Compared with the traditional thoriated tungsten, La-Mo cathode has higher emission current density at lower temperature, but it has poor emission stability. In order to improve the emission stability, systematical study on the emission mechanism of La-Mo cathode has been carried out. The life of La-Mo cathode has been improved and has achieved 1400 It, which exceeds the minimum life for practical uses (1000 h). As another alternative for thoriated tungsten cathode, Y-Mo cathode has shown better performance. The thermionic emission capability of Y-Mo cathode is between that of La-Mo cathode and Th-W cathode.

关键词： tungsten molybdenum thermonic cathode emission

Thermodynamic Functions and Phase Transformation of Metal Nanocrystals

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Journal of materials Science & Technology 2005年第5期21卷 705-709页

作者： Jinping GAO, Xiaoyan SONG , Jiuxing zhang, keyong YANG and Xuemei LIUCollege of materials Science and Engineering, the key laboratory of Advanced functional materials of the Education Ministry,Beijing University of Technology, Beijing 100022, China key laboratory of Advanced functional materials College of Materials Science and Engineering Beijing University of Technology Beijing 100022 China

A model to calculate the thermodynamic functions of the pure metal nanocrystals has been developed, with the consideration of the effects of both the interfaces and the crystal in the nano-grain interior. As an example, the enthalpy, entropy and Gibbs free energy, as functions of the excess free volume at interfaces, temperature and grain size, are calculated for the Co nanocrystals. Furthermore, the characteristics of β-Co→α-Co phase transformation are studied, and the transformation temperatures at different levels of grain size, as well as the critical grain sizes at different temperatures, are predicted. The calculation results show that, the nano-grained β-Co （fcc） is thermodynamically stable at temperatures much lower than that for the conventional coarse-grained materials, and may also stably exist at room temperature when the grain size is reduced to be small enough. The present model is verified by comparisons between the experimental findings and the theoretical predictions.

关键词： Thermodynamic function Nanocrystal Phase transformation

Electrospinning of ultrafine core/shell fibers for biomedical applications

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Science China Chemistry 2010年第6期53卷 1246-1254页

作者： zhang Hong,ZHAO ChenGuang,ZHAO YunHui,TANG GongWen & YUAN XiaoYan School of materials Science and Engineering,and Tianjin key laboratory of Composite and functional materials,Tianjin University,Tianjin 300072,China School of materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin University Tianjin China

Because of the inherent appearance similar to the natural extracellular matrix,ultrafine fibrous membranes prepared via electrospinning exhibit widespread applications,especially in the biomedical *** modifications of coaxial and emulsion electrospinning have drawn much attention in preparation of core/shell fibers for applications as tissue engineering scaffolds and controlled delivery systems for bioactive *** to incorporation of multi-components in the electrospun core/ shell fibers,the process of coaxial and emulsion electrospinning became more *** theories have not been fully understood.A series of investigations were carried out evaluating the systematic and processing *** paper reviews advantages and potentials of electrospun core/shell fibers as well as factors influencing their formation on the basis of our research and new progress.

关键词： core/shell fibers coaxial electrospinning emulsion electrospinning controlled delivery tissue engineering

THE COORDINATION ADSORPTION OF AMINES ON CARBOXYL RESIN IN Cu^(2+) FORM FROM NON-AQUEOUS MEDIUM AND DESORPTION WITH ANHYDROUS ELUANT

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Chinese Journal of polymer Science 2002年第5期20卷 439-444页

作者： Jia-zheng Li Zuo-qing Shi Yun-ge Fan The State key laboratory of functional polymer materials for Adsorption and Separation, Institute of polymer Chemistry Nankai University, Tianjin 300071, China College of Chemical Engineering Hebei University of Technology Tianjin 300130 China polymer materials for Adsorption and Separation Institute of Polymer Chemistry Nankai University 天津 300071

The adsorption of aniline, N-methylaniline and N,N-dimethylaniline onto carboxyl resin in Cu2+ form from water, ethanol and n-hexane have been studied. The results show that the adsorption affinities from n-hexane are higher than that from water, and nearly zero from ethanol. The separation factors for the adsorption of these three amines from mixed solution were also examined. The results of continuous column operations show that the breakthrough capacity of aniline from n-hexane reaches 90 mg/g dry resin in Cu2+ form, and the amines adsorbed can be stripped with anhydrous ethanol effectively. Adsorption onto carboxyl resin in Cu2+ form from non-aqueous medium and desorption with anhydrous eluant can overcome the run-off of Cu2+ from the resin, and would show potential advantages in the separation of some water-insoluble natural products.

关键词： coordination adsorption adsorption selectivity amine ligand

Preparation, Properties and Characterization of Modified CeO_2/La_2Zr_2O_7 Buffer Layers

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稀有金属材料与工程 2011年第S3期40卷 350-353页

作者： Cheng Yanling, Suo Hongli, Liu Min, Ma Lin, zhang Teng key laboratory of Advanced functional materials, Ministry of Education, Beijing University of Technology, Beijing 100124, China Beijing Univ Technol Coll Mat Sci & Engn Minist Educ Key Lab Adv Funct Mat Beijing 100124 Peoples R China

The metal organic deposition (MOD) method was used for the epitaxial growth of the CeO2/La2Zr2O7(LZO)/LZO seed layer structure on a cube-textured Ni5W substrate layer by layer. The material phase and the macro-orientations were analyzed by XRD. The surface morphology and the blocking performance of the buffer layer were investigated by SEM and AES. The grain orientation and the crystallographic growth mode of the CeO2 layer were first characterized by electron backscattering diffraction (EBSD). The uniformly distributed islanded LZO seed layer optimized both the in-plan and the out-plan orientation of the CeO2/LZO buffer layers, and the CeO2/LZO buffer layers with a thickness of 175 nm acted as an efficient Ni,W barrier. The EBSD analysis indicated that the crystallographic orientation of each layer can be obtained at various accelerating voltages for the multilayer sample, the percentage of {001} rotated cube texture of CeO2 layer reaching 97.4% at the accelerating voltage of 15 kV, thus showing epitaxial deposition with a high texture.

关键词： coated conductor buffer layer La2Zr2O7 seed layer CeO2 rotated cube texture accelerating voltage

Preparation and Selectivity of Molecularly Imprinted polymer Coating on the Micro Pore Membrane of Polytetrafluoroethylene

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Chinese Chemical Letters 2003年第9期14卷 979-982页

作者： Hong Sheng GUO, Yu Mei JIA, Xi Wen HEState key laboratory of functional polymer materials for Adsorption and Separation,Department of Chemistry, Nankai University, Tianjin 300071 The College of Pharmaceuticals and Biotechnology, Tianjin University, Tianjin 300072 State key Lab. Funct. Poly. Mat. A. Department of Chemistry Nankai University Tianjin 300071 China Coll. of Pharmaceut./Biotechnology Tianjin University Tianjin 300072 China

In order to obtain mechanically stable membrane for practical application, the imprinted polymer was synthesized in the pores of polyfluoromembrane, the binding and transport ability of the membrane were studied.

关键词： Molecular imprinting trimethoprim membrane of polytetrafluoroethylene.

Blue light emission from pulsed laser ablated polyethylene

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Optoelectronics Letters 2008年第1期4卷 23-25页

作者： QIN Chuan-li, BAI Xu-duo, ZHAO Shu-fang, LI Chen-ming, JIANG Hai-jian, and TAN Qiang key laboratory of functional polymer materials, School of Chemistry and materials Science, Heilongjiang University, Harbin 150080, China key laboratory of functional polymer materials School of Chemistry and Materials Science Heilongjiang University Harbin China

The 1064 nm pulsed laser was used to ablate polyethylene (PE) at different power. Compared with unmodified PE, the ablated polyethylene (PE) gave off obvious blue light under UV lamp irradiation. The morphology and tre structure of ablated and unmodified PE were studied by scanning electron microscope, fluorescence spectroscopy and raman spectroscopy. the results showed that double bonds existed in the ablated PE which resulted in obvious blue emission of ablated PE and the intensity of the laser had great influence on the physical properties and chemical structure of the PE surface.

关键词：脉冲激光器蓝光发射聚乙烯融化