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SYNTHESIS AND CHARACTERIZATION OF A NOVEL BLUE LIGHT EMITTING ROD-COIL DIBLOCK OLIGOMER

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Chinese Journal of Polymer science 2002年第5期20卷 401-407页

作者： Lifang Yang Haifeng He Hongqing Cao Xinhua Wan Qi-feng Zhou Department of Polymer science & engineering college of Chemistry & Molecular engineering Peking university beijing 100871, china Peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China

Four new rod-coil diblock molecules, which had well-defined para-phenylene oligomers (PPP, from biphenyl to quinquephenyl) as rigid segments and poly(ethylene oxide) (PEO, M-w ca. 750) as flexible segments, were synthesized. The chemical structure and the number of repeating unit in PEO coil and PPP rod were characterized by H-1-NMR and MALDI-TOF mass spectrometry. The diblock oligomers showed good solubility in common organic solvents and aggregated in water as characterized by a blue shift in UV-vis absorption spectra, a red shift in emission spectra, quenching of the fluorescence and formation of the microfibrilla and fractal-like structures. The formation of different supramolecular structures meant that this effort might lead to commercial important highly organized functional materials.

关键词： rod-coil diblock oligomer MALDI-TOF mass spectrometry microfibrilla aggregate fractal-like pattern

General regularity of dynamic responses of slopes under dynamic input

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science china(Technological sciences) 2003年第z1期46卷 120-132页

作者： QI Shengwen, WU Faquan & SUN Jinzhong Institute of Geology and Geophysics, Chinese Academy of sciences, beijing 100029, china college of engineering Technique, china university of Geosciences, beijing 100083, china Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China china Univ Geosci Coll Engn Techn Beijing 100083 Peoples R China

Through lots of numerical simulations with FLAC3D, dynamic responses of slopes are comprehensively studied in this paper and the general regularities of the isoline of the coefficient of the displacement, velocity and acceleration of the slope section are reached. Given a certain material slope, if the height of the slope is less than a certain value, the displacement, velocity and acceleration linearly enlarge with elevation in the vertical direction; if the height of the slope surpasses the certain value, the displacement,velocity and acceleration do not linearly enlarge with elevation any more, on the other hand, they fluctuate with a certain rhythm. At the same time, the rhythm appears in the horizontal direction, and the displacement, velocity and acceleration of the slope surface enlarge near the slope surface. The distribution form of the isoline of the coefficient of displacement, velocity and acceleration in the section of the slope is remarkably affected by the slope angle. In the certain area near the slope surface, the isoline of displacement,velocity and acceleration is parallel to the surface of the slope; in the mean time the strike direction of the extremum area is parallel to the surface of the slope, too. The charts of the slope dynamic responses can be depicted with two indexes, one is the strike direction of the isoline, and the other is the number of the rhythm extremum area of the direction parallel to the surface of the slope.

关键词： slope, dynamic response, regularity, rhythm.

Controlling the Molecular Weight and Molecular Weight Distribution using Compressed CO_2 Antisolvent

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Chinese chemical Letters 2000年第10期11卷 933-934页

作者： Jun LIU, Zhi Min LIU, Bu Xing HAN, Jian WANG, Qing HUO, Fang Fang LIU (Center For Molecular sciences, Institute of Chemistry, Chinese Academy of sciences, beijing 100080 (chemical engineering college of beijing United university, beijing 100023) (Department of chemical engineering, university of science and technology of Hebei, Shijiazhuang 050018) Chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China beijing United Univ Chem Engn Coll Beijing 100023 Peoples R China Univ Sci & Technol Hebei Dept Chem Engn Shijiazhuang 050018 Peoples R China

Effect of CO2 dissolved in tetrahydrofuran (THF) on the polymerization of styrene in THF was studied at 333.2 K and different pressures. It was found that the molecular weight (MW) and MW distribution of the polystyre... 详细信息

关键词： CO_2 antisolvent styrene polymerization

The Compatibility of Polycarboxylate-Type Superplasticizers with Cement

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Journal of Wuhan university of technology(materials science) 2005年第3期20卷 95-98页

作者：李崇智 Department of Civil engineering Beijing Institute of Civil Engineering and Architecture

Four polycarboxylate- type （ PC ） superplasticizers of different functional groups were used ; their dispersing and retaining behaviors were analyzed through ZETA potential measurement, mini-slump test of cement paste and performance test of concrete. The experimental results show that the dispersing and flow-retaining ability of PC was determined by two factors of anionic groups and nonionic groups ： the density of anionic groups - COO^- or - SO3^- acted on the electronic repulsive force. and the length and proportion of nonionic graft groups of PEO in PC chemical stracture affected the steric effect. The compatibility between PC superplasticizers and cement mainly depended on the type of PEO groups ; furtlwrmore, adding mineral powders is good to the compatibility for high performance concretes （ HPCs ）.

关键词： PC superplasticizers cement compatibility

chemical Extraction Preparation of Delithiated Cathode materials of Li-ion Battery

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Journal of Wuhan university of technology(materials science) 2009年第6期24卷 863-866页

作者：闫时建 School of materials science and engineering Taiyuan University of Science and Technology

A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2S2O8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents.

关键词： chemical extraction delithiated cathode material Li-ion battery

Effects of combined substitution of Dy and Mo or Si on the crystal structures and magnetic properties of Nd_(1-y)Dy_yFe_(11-x)TiM_x(M=Mo,Si) compounds

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science china Chemistry 2009年第8期52卷 1097-1103页

作者： LI XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin college of Chemistry and chemical engineering,Graduate university of Chinese Academy of sciences,beijing 100049,china 1. college of Chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12-type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

Complex variable method for plane elasticity of icosahedral quasicrystals and elliptic notch problem

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science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 773-780页

作者： LI LianHe1,2 & FAN TianYou1 1 Department of Physics, beijing Institute of technology, beijing 100081, china 2 college of Mathematics science, Inner Mongolia Normal university, Hohhot 010022, china Department of Physics Beijing Institute of Technology Beijing 100081 China college of Mathematics science Inner Mongolia Normal University Hohhot 010022 China

The complex variable method for the plane elasticity theory of icosahedral quasicrystals is developed. Based on the general solution obtained previously, complex representations of stress and displacement components of phonon and phason fields in the quasicrystals are given. With the help of conformal transformation, an analytic solution for the elliptic notch problem of the material is presented. The solution of the Griffith crack problem can be observed as a special case of the results. The stress intensity factor and energy release rate of the crack are also obtained.

关键词： icosahedral quasicrystals plane elasticity elliptic notch complex variable method

PRECIPITATION AND MICROSTRUCTURE OF Cr MODIFIED Al_3Ti

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Acta Metallurgica Sinica(English Letters) 2001年第1期14卷 13-20页

作者： W.H. Tian and M. Nemoto (Department of materials Physics and Chemistry, university of science and technology beijing, beijing 100083, china Sasebo National college of technology, Okishin 1-1, Sasebo 857-1193, Japan) Dept. of Mat. Phys. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The microstructures of Cr modified Al3Ti containing Al2Ti and L10-AlTi precipitates have been investigated in terms of transmission electron microscopy(TEM). Fine precipitation of Al2Ti (Ga2Hf type structure) and Ll0-AlTi(Cr) occurs in Ll2-Al3Ti(Cr) by aging around 973K. The aging behavior was investigated by microhardness measurements. TEM observations reveal that plate-like Al2Ti precipitates lie on{100} planes of the Ll2-Al3Ti(Cr) matrix with the c axis of the tetragonal phase perpendicular to the thin plate. As contrast with Al2Ti precipitates, Ll0-AlTi(Cr) precipitates form thin plate and lie on {100} planes of Ll2-Al3Ti(Cr) matrix at the initial aging time and for long time aging the habit plane of the thin plate deviates from {100} plane and finally forms a kinked plate. The coherency stresses across the precipitate/matrix interface are considered to be the main factors controlling the precipitate morphology.

关键词： Age hardening Aluminum compounds Microstructure Precipitation (chemical) Titanium compounds

Applications of functionalized ionic liquids

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science china Chemistry 2006年第5期49卷 385-401页

作者： LI Xuehui1, ZHAO Dongbin2,3, FEI Zhaofu2 & WANG Lefu1 1. Department of chemical engineering, Guangdong Provincial Laboratory of Green chemical technology, South china Uni-versity of technology, Guangzhou 510641, china 2. Swiss Federal Institute of technology, Lausanne, EPFL, CH-1015 Lausanne, Switzerland 3. PKU Green Chemistry Center, beijing National Laboratory for Molecular sciences, college of Chemistry and Molecular engineering, Peking university, beijing 100871, china 1. Department of chemical engineering Guangdong Provincial Laboratory of Green Chemical Technology South China University of Technology Guangzhou 510641 China 2. Lausanne EPFL Swiss Federal Institute of Technology CH-1015 Lausanne Switzerland 3. PKU Green Chemistry Center Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Recent developments of the synthesis and applications of functionalized ionic liquids (including dual-functionalized ionic liquids) have been highlighted in this review. Ionic liquids are at-tracting attention as alternative solvents in green chemistry, but as more functionalized ILs are pre-pared, a greater number of applications in increasingly diverse fields are found.

关键词： ionic liquids functionalized ionic liquids dual-functionallzed ionicliquids reaction media asymmetric synthesis nano-materials porous materials lubricants flue-gas desulfurization oil desul-furization