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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 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 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

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

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 100081 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

Raman Scattering and t-Phase Lattice Vibration of 3% (mole fraction) Y_2O_3-ZrO_2

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Journal of Materials Science & technology 2004年第5期20卷 485-489页

作者： Xinglun TANG and Xinhua ZHENGschool of Materials Science and engineering, beijing institute of technology, beijing 100081, china Sch. of Mat. Sci. and Eng. Beijing Inst. of Technol. Beijing 100081 China

The Raman spectra of 3% (mole fraction) Y2O3-ZrO2 (3Y) are obtained at different temperature from 77 K to 853 K. The results show that 260 cm-1 Eg and 460 cm-1 Eg modes on the spectra shift toward lower wave number with the increase of temperature; meanwhile, the continuity of the Half Width at Half Maximum (HWHM) and wave number (frequency) of Raman bands are broken and t-phase only partially transforms to m-phase at 523 K. Based on the experimental results, this paper discusses the t-phase lattice vibration of 3Y and presents the images of vibration displacement of six Raman-active modes for t-phase of ZrO2. The analysis indicates that there are diversities existing in the displacement of the atomic vibration of Raman-active modes because of their different symmetries at various temperature, which leads to the different change tendencies of Raman bands. Furthermore, the abrupt changes of some Raman-active modes indicating the atomic displacement are assumed to be the condensations of phonon modes in the t→m phase transition.

关键词： Raman scattering Zirconia Phase transition Condensation of phonon

Structures and aromaticity of the planar Al_2P_2^(n-) (n=1―4) clusters

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Science china Chemistry 2009年第12期52卷 2237-2242页

作者： XU WenGuo,ZHANG YuanChun & ZHAI Lei institute of chemical Physics,beijing institute of technology,beijing 100081,china 1. institute of chemical Physics Beijing Institute of Technology Beijing 100081 China

Clusters Al2P2n-(n = 1―4) were theoretically investigated using density functional theory (DFT) methods at the B3LYP/6-311+G* and B3PW91/6-311+G* levels of theory. The calculated results showed that the planar structure (D2h symmetry) of Al2P2n-(n = 1―4) species was the global minimum. And the negative nucleus-independent chemical shift (NICS) value of Al2P2n-(n = 1―4) species indicated the existence of a ring current in the planar structure (D2h symmetry). A detailed molecular orbital (MO) analysis revealed that the planar structures (D2h symmetry) had π aromaticity,which further exhibited the strongly aromatic character for Al2P2n-(n = 1―4) species.

关键词： DFT calculation geometric structure nucleus-independent chemical shift molecular orbital

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) beijing Inst Technol Sch Chem Engn & Mat Beijing 100081 Peoples R 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