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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 chemical 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 engineering 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

Modification of LiCo_(1/3)Ni_(1/3)Mn_(1/3)O_2 cathode material by CeO_2-coating

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Science china(Technological Sciences) 2009年第9期52卷 2737-2741页

作者： WANG Meng,WU Feng,SU YueFeng & CHEN Shi beijing Key Laboratory of environment,school of chemical engineering and environment,beijing institute of technology National Development Center of High technology Green Materials,beijing 100081,china beijing Key Laboratory of environment School of Chemical Engineering and Environment Beijing Institute of Technology Beijing China National Development Center of High technology Green Materials Beijing China

LiCo1/3Ni1/3Mn1/3O2 was coated by a layer of 1.0 wt% CeO2 via sol-gel method. The bared and coated LiMn1/3Co1/3Ni1/3O2 was characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),cyclic voltammogram (CV) and galvanotactic charge-discharge test. The results show that the coating layer has no effect on the crystal structure,only coating on the surface; the 1.0 wt% CeO2-coated LiCo1/3Ni1/3Mn1/3O2 exhibits better discharge capacity and cycling performance than the bared LiCo1/3Ni1/3Mn1/3O2. The discharge capacity of 1.0 wt% CeO2-coated cathode is 182.5 mAh.g-1 at a current density of 20 mA.g-1,in contrast to 165.8 mAh.g-1of the bared sample. The discharge capacity retention of 1.0 wt% CeO2-coated sample after 12 cycles reaches 93.2%,in comparison with 86.6% of the bared sample. CV results show that the CeO2 coating could suppress phase transitions and prevent the surface of cathode material from direct contact with the electrolyte,thus enhance the electro-chemical performance of the coated material.

关键词： LiCo1/3Ni1/3Mn1/3O2 CeO2 coating Lithium-ion battery

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,beijing institute of technology,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 engineering, beijing institute of Petro-chemical technology, beijing 102617, 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

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, beijing institute of technology, 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

Oxidative Debenzylation and Acetylation of Hexabenzylhexaazaisowutzitane

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含能材料 2002年第2期10卷 66-68页

作者： PANG Si-ping, Yü Yong-zhong, ZHAO Xin-qi (school of chemical engineering and Material Science, beijing institute of technology, beijing 100081, china) school of chemical engineering and Material Science Beijing Institute of Technology 北京 100081

The oxidative reactivity of hexabenzylhexaazaisowutzitane(HBIW)under different conditions was studied. It was found that the N-benzyl groups were found to form benzoyl group after oxidation. They might also be first d... 详细信息

关键词：氧化乙酰化炸药 HBIW 苯甲基

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 engineering & 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

DESIGN AND EXPERIMENT OF ELECTRIC BUS

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Chinese Journal of Mechanical engineering 2002年第1期15卷 57-61页

作者： Sun Fengchun Chen Yong Zhang Chengning Sun Liqing school of Vehicle and Transportation engineering，beijing institute of technology， beijing 100081，china school of Vehicle and Transportation engineering Beijing Institute of Technology 北京 100081

Performance and reliability experiments on BJD-6100EV electric buses, jointlydeveloped by beijing institute of technology and beijing Public Transport Company, are *** power model of battery pack is established and maximum output power is analyzed. A permanentmagnetic direct current (PMDC) motor with enhanced windings is developed for the bus. Torque-speedcharacteristics of the motor are modeled and performance of electric bus is analyzed. Computationalmethod of the range of electric bus is proposed and discussed. Experiments show that electric buscan realize design requirements. Computational methods are verified with the help of field test. Itis expected that design and computation method will provide helpful reference to development ofelectric vehicles.

关键词： Electric bus Storage battery Electric motor Range Performancecharacteristics

Study on the Miscibility and Phase Behavior of Polyoxymethylene with Novolak

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Journal of Materials Science & technology 2000年第4期16卷 427-430页

作者： Xiaodong WANG, Hangquan LI and Riguang JIN (school of Materials Science and engineering, beijing University of chemical technology, beijing 100029, china) school of Materials Science and engineering Beijing University of Chemical Technology Beijing 100029 China

The miscibility and phase behavior of the blends of polyoxymethylene (POM)/Novolak were investigated by the cloud point method, which showed that the POM/Novolak blends exhibited a lower critical solution temperature. The melting point of POM decreased when diluted with Novolak. From the melting temperature depression of POM, a negative interaction parameter (x) between POM and Novolak was obtained. The IR spectrum revealed that the miscibility between POM and Novolak was caused by the specific interaction between the OH groups of Novolak and the ether oxygen atoms of POM. The morphology of the blends investigated by polarized light microscopy showed that the size of spherulites of POM was sharply decreased by its mixing with Novolak. This suggests that Novolak be used as a compatibilizer for POM.

关键词： POM Study on the Miscibility and Phase Behavior of Polyoxymethylene with Novolak

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, beijing 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 Beijing China school of chemical engineering and environment Beijing Institute of Technology Beijing China

LiNi0.33Mn0.33-xCo0.33CrxO2 (x=0, 0.01, 0.025, 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= 0.025 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