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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 {2.,beijing 100080,China 2.College of Chemistry and Chemical Engineering,{3. University of chinese Academy of {2.,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,13. 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

Conceptual design,data model and key techniques of“3. Assistant”

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中国有色金属学会会刊：英文版 2011年第S3期21卷 692-698页

作者： LI Qing-yuan1, ZHANG Xuan2. JIN Yang2. ZHOU Hui3. WANG Qian-jin3.WEI Zhan-yin1 1. Key Laboratory of Geo-Informatics, {2. Academy of Surveying and Mapping, beijing 10083., China 2. school of Geo-Science and Surveying Engineering, China University of Mining and Technology, beijing 100083. China 3. school of Geomatics, Liaoning Technical University, Fuxin 12.0}00, China [a] Key Laboratory of Geo-Informatics Chinese Academy of Surveying and Mapping Beijing 100830 China [b] school of Geo-Science and Surveying Engineering China University of Mining and Technology Beijing 100083 China [c] school of Geomatics Liaoning Technical University Fuxin 123000 China

Conceptual design, data model and key techniques of "Geo-engineer 3. assistant", an underground 3. GIS oriented to geology and mine application, were discussed. In particular, the importance of high-order smoothing triangular pieces to surface's fine expression in geological modeling was emphasized. The contour mode is the most favorite mode of the three modes about surface expression: DEM, TIN and contour. Topology in underground 3. modeling with CAGD was compared. From the view of boundary and coboundary, which is soul of IS 19107 (Geographic information spatial schema), 3. underground topology was re-examined.

关键词： 3. assistant true 3. GIS fine expression of surface contour mode 3. topology

Synthetic aperture radar tomography sampling criteria and three-dimensional range migration algorithm with elevation digital spotlighting

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Science in China(Series F) 2009年第1期52卷 100-114页

作者： TAN WeiXian1,2.3., HONG Wen1,2. WANG YanPing1,2. LIN Yun1,2.3.& WU YiRong1,2.1 State Key Laboratory of Microwave Imaging Technology, {2. 100190, China 2.Institute of Electronics, chinese Academy of sciences, {2. 100190, China 3.graduate school, chinese Academy of sciences, {2. 100190, China State Key Laboratory of Microwave Imaging Technology Beijing 100190 China Institute of Electronics Chinese Academy of Sciences Beijing 100190 China graduate school Chinese Academy of Sciences Beijing 100190 China

Based on the general geometric model of multi-baseline Synthetic Aperture Radar Tomography （TomoSAR）, the three-dimensional （3.D） sampling criteria, the analytic expression of the 3.D Point Spread Function （PSF） and the 3.D resolution are derived in the 3.D wavenumber domain in this paper. Considering the relationship between the observation geometry and the size of illuminated scenario, a 3.D Range Migration Algorithm with Elevation Digital Spotlighting （RMA-EDS） is proposed. With this algorithm 3.D images of the area of interest can be directly and accurately reconstructed in the 3.D space avoiding the complex operations of 3.D geometric correction. Finally, theoretical analyses and simulation results are presented to demonstrate the shift-varying property of the 3.D PSF and the spatialvarying property of the 3.D resolution and to demonstrate the validity of the 3.D RMA-EDS.

关键词： synthetic aperture radar tomography (TomoSAR) three-dimensional (3.D) SAR imaging 3.D sampling criteria 3.D resolution,3.D range migration algorithm with elevation digital spotlighting (RMA-EDS)

Review on the study of entanglement in quantum computation speedup

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chinese Science Bulletin 2007年第16期52卷 2161-2166页

作者： DING ShengChao1,3.& JIN Zhi1,2.1 Institute of Computing Technology,chinese Academy of {2.,beijing 100080,China 2.Academy of Mathematics and Systems Science,chinese Academy of {2.,beijing 100080,China 3.graduate University of chinese Academy of {2.,beijing 100080,China Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China

The role the quantum entanglement plays in quantum computation speedup has been widely disputed. Some believe that quantum computation's speedup over classical computation is impossible if entan-glement is absent,while others claim that the presence of entanglement is not a necessary condition for some quantum algorithms. This paper discusses this problem systematically. Simulating quantum computation with classical resources is analyzed and entanglement in known algorithms is reviewed. It is concluded that the presence of entanglement is a necessary but not sufficient condition in the pure state or pseudo-pure state quantum computation speedup. The case with the mixed state remains open. Further work on quantum computation will benefit from the presented results.

关键词：量子论量子纠缠量子计算加速模拟

Study on the coating of nano-scale SiO_2.film on the surface of nanocrystalline Mg-Al layered double hydroxides

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Science China Chemistry 2005年第2期48卷 107-114页

作者： ZHANG Zejiang1,2.3. MEI Xiujuan2. XU Chenghua1 & QIU Fali1 1. Chengdu Institute of Organic Chemistry, chinese Academy of {2., Chengdu 610041, China 2. Sichuan Fire Research Institute of Public Security Ministry, Chengdu 61183., China 3. graduate {3. of the chinese Academy of {2., beijing 100039, China Correspondence should be addressed to Zhang Zejiang (email: zzjzzjzz@***) 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. Sichuan Fire Research Institute of Public Security Ministry 611830 Chengdu China 3. graduate {2. of the chinese Academy of {3. 100039 Beijing China

The coating process of a nano-scale SiO2.film on the nanocrystalline Mg-Al layered double hydroxides via a sol-gel process was investigated. The uniform and dense SiO2.ilm with a thickness of about 5 nm on the nano-LDHs particles was characterized by the solubility test in the dilute HNO3.or HCl acid, TEM and FT-IR, XRD, TG and DSC. The chemical shifts of binding en- ergies of Al 2., Mg 2., Si 2. and O 1s on the coated particles indicate that the coating of the SiO2.nano-film on the surface of the nano-LDHs proceeds through the formation of Mg-O-Si and Al-O-Si bonds. The thermal analysis shows that both the SiO2.coated nano-LDHs and the nano-LDHs have a similar mass loss process, in which there are three obvious stages of mass loss in the temperature range of 40—700℃. Furthermore, the more the coatedamount of SiO2.n the surface of the nano-LDHs is, the less the mass loss of the samples is at 700℃.The nano- LDHs have two obvious endothermic peaks at 2.4.67℃ and 43..13., whose corresponding heat absorption capacities are 412.2. J/g and 3.6.3. J/g, respectively. In contrast, the coated nano-LDHs have only one endothermic peak at 2.3.60℃ with a heat absorption capacity of 2.1.2. J/g.

关键词： layered double hydroxides, nanocrystalline, silica, coating.

Infrared Galaxies in the Nearby Universe

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chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 643-652页

作者： Jian-Ling Wang 1 National Astronomical Observatories,chinese Academy of sciences,{2. 100012.China 2.{3. school of chinese Academy of sciences,{2. 100049,China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China graduate school of {2. Academy of {3. Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5 （DR5） to study the morphological properties of 113. nearby infrared （IR） galaxies, most of which are brighter than 15.9 mag in r-band. This sample was drawn from a cross-correlation of the Infra-Red Astronomical Satellite （IRAS） point source catalog redshift survey with DR5 at z ≤ 0.08. Based on this IR galaxy sample, we constructed five volume-limited sub-samples with IR luminosity ranging from 10^9.5 L⊙ to 10^12.⊙. By deriving the IR luminosity functions （LF） for different morphological types, we found that normal spiral galaxies are the dominant population below LIR ~ 8 ~ 10^10 L⊙; while the fraction of barred spiral galaxies increases with increasing IR luminosity and becomes dominant in spiral galaxies beyond LIR ≈ 5 × 10^10L⊙. As the IR luminosity decreases, the IR galaxies become more compact and have lower stellar masses. The analysis also shows that normal spiral galaxies give the dominant contribution to the total comoving IR energy density in the nearby universe, while, in contrast, the contribution from peculiar galaxies is only 3.%.

关键词： galaxies evolution galaxies interactions galaxies starburst infrared galaxies galaxies luminosity function

Synthesis of well-defined functional PE graft copoly-mers via ATRP process

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Science Bulletin 2005年第10期50卷 1048-1051页

作者： CAO Chengang1, 2. DONG Jinyong1 & HU Youliang1 1. CAS Key Laboratory of Engineering Plastics, Joint Laboratory of Polymer Science and Materials, Institute of Chemistry, chinese Academy of sciences, {2. 100080, China 2. {3. school, chinese Academy of sciences, beijing 100039, China CAS Key Laboratory of Engineering Plastics Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China graduate school Chinese Academy of Sciences Beijing 100039 China

In summary, we have demonstrated a convenient yet highly efficient method forthe preparation of PE-based graft copolymers via ATRP.. By introducing a small amount of styrenegroups into PE chains via the selective copolymerization of ethylene with 1,4-divinylbenzenecatalyzed by Et(Ind)_2.rCl_2.MAO, the multifunctional ATRP initiator of1-chloroethylbenzene-containing PE was readily achieved by a quantitative hydrochlorination reactionand was shown to be very effective for the initiation of graft polymerization of MMA and styrene toprepare structurally well-defined PE-based graft copolymers.

关键词： ATRP Synthesis of well-defined functional PE graft copoly-mers via ATRP process PE well

Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1 & GOU Chenhua1,2.1. Institute of Engineering Thermophysics, chinese Academy of sciences, {2. 100080, China 2. {3. school, chinese Academy of sciences, {2. 100080, China 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China 2. graduate school Chinese Academy of Sciences Beijing 100080 China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System

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Wuhan University Journal of Natural sciences 2005年第4期10卷 779-784页

作者： ZHANG Ren-jun 1,2.1. Institute of Mountain Hazards and Environment, chinese Academy of sciences, Chengdu 610041, Sichuan, China 2. {2.d {3. of the chinese Academy of sciences, beijing 100039, China chinese Academy of sciences Institute of Mountain Hazards and Environment Chengdu Sichuan China (GRID:grid.9227.e) (ISNI:***) graduated school of the {2. Academy of {3. Beijing China (GRID:grid.9227.e) (ISNI:***)

Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts.

关键词： tourist resort carrying capacity TSBS GIS Multi-Agent simulator