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An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science China Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3 1 Technical institute of Physics and Chemistry,Chinese Academy of Sciences,beijing 100080,China 2.College of Chemistry and {2. engineering,Graduate University of Chinese Academy of Sciences,beijing 100049,China 3 school of chemical engineering and environment,beijing institute of technology,beijing 100081,China Technical institute of Physics and Chemistry Chinese Academy of Sciences Beijing China College of Chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing China school of chemical {2. and environment Beijing Institute of Technology Beijing China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Research progress in synthesis and catalysis of polyoxometalates

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Progress in Natural Science:Materials International 2005年第5期15卷 385-394页

作者： GONG Yun1, HU Changwen1* and LIANG Hong2.1. Department of Chemistry, school of Science, the institute for {2. Physics, beijing institute of technology, beijing 100081, China 2. {2. Industry Press, beijing 10002., China) Department of Chemistry School of Science the Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China chemical Industry Press Beijing 100029 China

Recent progress in the synthetic chemistry and catalysis of polyoxometalates (POMs) is reviewed. The novel POMs and their derivatives emerging in nearly three years (2.02.2.04) are introduced, including POMs with novel structure, POMs-organic hybrid compounds and host-guest complexes. Our review is focused on the elaboration of POMs' supramolecular chemistry.

关键词： polyoxometalates hybrid host-guest structure supramolecule catalysis.

A Good GC Stationary Phase for Separation of Xylene Isomers

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Chinese chemical Letters 1999年第1期10卷 45-46页

作者： Ting ZHANG Jiang Hua HAN Ruo Nong FU Jian ZHANG(school of chemical {2. & Materials, beijing institute of technology, beijing 100081) Sch. of Chem. Eng. and Materials Beijing Institute of Technology Beijing 100081 China

An excellent separation of xylene isomers is reported using 2. 6-O-di-pentyl-3-O-acetyl-beta-CD as capillary stationary phase. The optimum conditions for the separation are also discussed.

关键词： xylene isomers separation capillary stationary phase optimum conditions for separation

The mathematical model of wetting angle of heterogeneous nucleation

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Science China(Technological Sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2.& ZHAO Pei3 1. school of Metallurgical and Ecological engineering, University of Science and {2. beijing, beijing 100083, China 2. school of Material Science, University of Science and {2. beijing, beijing 100083, China 3. Central Iron and Steel Research institute, beijing 100081, China school of Metallurgical and Ecological engineering University of Science and Technology Beijing school of Material Science University of Science and Technology Beijing

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2.3 are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

Investigation of Phase Excitation Effect on Mixing Control in Coaxial Jets

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Journal of Thermal Science 2009年第4期18卷 364-369页

作者： Yanming LIU,Baoguo WANG and Shuyan LIUschool of Aerospace engineering,{2.,beijing,100081,China school of Aerospace engineering Beijing Institute of Technology Beijing China

Detailed unsteady numerical simulation has been carried out to investigate the mechanism of adjacent syntheticjets and the influence of different phases on the mixing of coaxial jets. The results show the combined jet, formedby coupling the vortex pairs at the orifice of two adjacent actuators, can exhibit better controlling effect. Spanwisepressure difference appears because of the existence of phase difference between the left jet and right jet, whichresults in the variation of the combined jet. When the phase difference is greater than zero, mixing enhancementof coaxial jets can be achieved, but there are maximum phase difference and optimal phase difference. On thecontrary, application of adjacent synthetic jets always leads to the mixing reduction when phase difference is lessthan zero.

关键词： adjacent synthetic jets phase difference mixing controlling ability

Preparation of a Novel Micro/nano Tubes via Electrospun Fiber as a Template

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Journal of Materials Science & technology 2004年第5期20卷 613-616页

作者： Taiqi LIUschool of Materials and chemical {2., beijing institute of Petro-chemical technology, beijing 102.17, China Sch. of Mat. and Chem. Eng. Beijing Inst. of Petrochem. Technol. Beijing 102617 China

Poly (para-xylylene) hollow fibers with inner diameters can be prepared via template fibers electrospun from solutions. The PPX is deposited from the vapor phase and the template fiber is selectively removed by heat treatment or solvent extraction. The PPX is partially crystalline and the crystal modification depending on the route is used to extract the template fiber. The thermal stability of the hollow fibers is only slightly reduced relative to the bulk material and the same holds for the UV-stability.

关键词： Electrospinning Fiber chemical vapor deposition Physical vapor deposition Crystal Conductivity

Different Aggregation Behaviors of Tetra-(4-hydroxyphenyl) Porphyrin (THPPH_2. in the Inner Core and on the Surface of CTAB Micelles

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Chinese chemical Letters 2000年第10期11卷 929-930页

作者： Chen MA, Yun Hong ZHANG, Chang Song FU, Qian Shu LI (school of chemical {2. and Materials Science, beijing institute of technology, beijing 100081) school of chemical {2. and Materials Science Beijing Institute of Technology

The UV-Vis spectra of THPPH2.in CTAB micelles at pH7.2.and pH11.0 were analyzed to study the effect of micellar environments on the aggregation behaviors of this porphyrin.

关键词： THPPH_2 CTAB micelles aggregation UV-Vis spectra.

Improvement of the electrochemical performance of LiNi_(0.33)Mn_(0.33)Co_(0.33)O_2.cathode material by chromium doping

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Science China(Technological Sciences) 2010年第12期53卷 3214-3220页

作者： WANG Meng1, CHEN YunBo1, WU Feng2. SU YueFeng2.& CHEN Lin1 1 Advanced Manufacture technology Center, China Academy of Machinery Sicence and technology, {2. 100083, China 2.school of chemical engineering and environment, beijing institute of technology, beijing 100081, China Advanced Manufacture technology Center China Academy of Machinery Sicence and Technology school of chemical {2. and environment Beijing Institute of Technology

LiNi0.33Mn0.33-xCo0.33CrxO2.(x=0, 0.01, 0.02., 0.05) materials were synthesized by Cr3+ substitute of Mn4+ to enhance their electrochemical properties. The structure and electrochemical properties were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and charge/dis charge tests. The materials maintained the α-NaFeO2.type layered structure and the discharge capacities were also increase by doping appropriate amount of Cr3+. The sample with x= 0.02. exhibited the highest discharge capability of 181.6 mAh g?1 and the best cycle performance. EIS measurement showed that the Cr-doped electrode had the lower resistance impedance increase during cycling. The chemical diffusion coefficient of Li+ ion (DLi) was measured by potentiostatic intermittent titration technique (PITT). The result showed that DLi in Cr-doped electrode was faster than that of the un-doped one.

关键词： cathode material Cr-doped Li-ion battery electrochemical properties

The influence of synthetic jet excitation on secondary flow in compressor cascade

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Journal of Thermal Science 2010年第6期19卷 500-504页

作者： Yanming LIU, Tuo SUN, Chaobin GUAN and Baoguo WANG school of Aerospace engineering, {2., beijing, 100081, China Assistant Professor school of Aerospace engineering Beijing Institute of Technology Beijing China

The detailed numerical simulation has been carried out to investigate the effect of synthetic jet excitation on the secondary flow at 5° incidence in a compressor cascade, in which the synthetic jet actuation is equipped on the suction surface. The influence of excitation position, one fixed near the trailing edge and the other fixed a little far from the trailing edge, has also been studied. The results show that unsteady disturbance of desirable synthetic jet effectively enhances the mixing of the fluid inside the separation region, which reduces the vortex intensity and the energy loss, improves the flow status in the cascade, and also suppresses velocity fluctuation near the trailing edge. Additionally, the actuation fixed near the separation region proves to be more effective and exit load distribution is more uniform due to the employment of the synthetic jet.

关键词： synthetic jet actuator compressor cascade loss velocity fluctuation