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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 {3.,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,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

Improvement of the SLP simulation in the coupled AGCM-ocean surface wave model

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chinese science Bulletin 2005年第20期50卷 2397-2400页

作者： YU Weidong1, 2, 3. LI Zhaoxin4 & YUAN Yeli3.1. Institute of Oceanology, chinese academy of sciences, Qingdao 266071, china 2. Graduate School of chinese academy of sciences, Beijing 100049, china 3. Laboratory of Marine science and Numerical Modeling, First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, china 4. LMD/CNRS, Univ. Paris 6, Paris, France Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School of chinese academy of sciences Beijing 100049 China Laboratory of Marine science and Numerical Modeling First Institute of Oceanography State Oceanic Administration Qingdao 266061 China LMD/CNRS Univ. Paris 6 Paris France

The coupled atmosphere-ocean general circulation models (CGCM) are now becoming the indispensable tools for the climate study. However, most models still suffer from unrealistic simulations. One problem is the troublesome climate drift. It may come from some unresolved aspects. One possibility is the poor air-sea surface flux description now adopted in CGCM. The commonly used solution for this problem is the so-called flux correction[1].

关键词：大气海洋循环模式气象学 SLP模拟

Synthesis,crystal structure and thermal behavior of Rb(NTO)·H_2O

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chinese science Bulletin 2001年第1期46卷 45-49页

作者： HU Mancheng, GAO Shiyang, LIU Zhihong, SONG Jirong, XIA Shuping & YU Kaibei1. Institute of Applied Chemistry, Shaanxi Normal University, Xi’an 710062, china 2. Department of Chemical Engineering, Northwest University, Xi’an 710069, china 3. Chengdu Branch of chinese academy of sciences, Chengdu 610041, china Institute of Applied Chemistry Shaanxi Normal University Xi’an China Department of Chemical Engineering Northwest University Xi’an China Chengdu Branch of chinese academy of sciences Chengdu China

The Rb(NTO) .H2O crystal has been synthesized by reaction of 3.nitro-l,2,4-triazole-5-one (NTO) with Rb2CO3.in aqueous solution. Its crystal structure has been determined. The crystal belongs to monoclinic system. Crystal structure data: space group P21/ n; a = 0.63. 0(1), b = 0.824 1(2), c =1.296 4(3. nm; β = 97.90(1)°; V = 0.669 9 (2) nm3. Z = 4, Dc= 2.3.6 g/cm3.μ = 7.3.5 nm-1, F(000) = 448. An eight coordinated compound is formed between Rb+ with oxygen atoms and nitrogen atoms. A layer structure is formed by coordination bonds and hydrogen bonds. The thermal decomposition mechanism of this coordination compound is discussed.

关键词： Rb-NTO coordination compound crystal structrue thermal decomposition.

An SGS Model and Its application

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Communications in Nonlinear science and Numerical Simulation 1999年第2期4卷 87-90页

作者： Zhengtong XIE Jiachun LI (Institute of Mechanics, chinese academy of sciences, Beijing 100080, china) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Based on the turbulent energy and structure function model, a subgridstress model named transitional structure function (TSF) is proposed, which exhibitsmore satisfactory performance than the previous one when applied in turbulent flow withinand above forest *** time and horizontal averaged statistics such as mean verticalprofiles of wind velocity, Reynolds stress, turbulent kinetic energy etc., and instantaneousfields as well are in general agreement with earlier observations, at least in a qualitativesense.

关键词： Large-Eddy simulation SGS model turbulent flow canopy

Birthrates and delay times of Type Ia supernovae

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science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 586-590页

作者： WANG Bo1,2,3. LIU ZhengWei1,2,3. HAN YunKun1,2,3. LEI ZhenXin1,2,3. LUO YangPing1,2,3.& HAN ZhanWen1,2 1National Astronomical Observatories/Yunnan Observatory, chinese academy of sciences, Kunming 650011, china 2Key Laboratory for the Structure and Evolution of Celestial Objects, chinese academy of sciences, Kunming 650011, china 3.raduate University of chinese academy of sciences, Beijing 100049, china National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming China Graduate University of chinese academy of sciences Beijing China

Type Ia supernovae (SNe Ia) play an important role in diverse areas of astrophysics, from the chemical evolution of galaxies to observational cosmology. However, the nature of the progenitors of SNe Ia is still unclear. In this paper, according to a detailed binary population synthesis study, we obtained SN Ia birthrates and delay times from different progenitor models, and compared them with observations. We find that the Galactic SN Ia birthrate from the double-degenerate (DD) model is close to those inferred from observations, while the birthrate from the single-degenerate (SD) model accounts for only about 1/2-2/3.of the observations. If a single starburst is assumed, the distribution of the delay times of SNe Ia from the SD model is a weak bimodality, where the WD + He channel contributes to the SNe Ia with delay times shorter than 100 Myr, and the WD + MS and WD + RG channels to those with age longer than 1 Gyr.

关键词： binaries: close stars: evolution supernovae: general white dwarfs

The gravitational gradient tensor’s invariants and the related boundary conditions

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science china Earth sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2,3.& ZHAO DongMing4 1 College of Earth science, Graduate University of chinese academy of sciences, Beijing 100049, china 2 Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 43.077, china 3.State Key Laboratory of Astronautic Dynamics, Xi’an 710043. china 4 Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052, china College of Earth science Graduate University of Chinese Academy of Sciences Beijing China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China State Key Laboratory of Astronautic Dynamics Xi’an China Zhengzhou Institute of Surveying and Mapping Zhengzhou China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2-term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2/2 T), which is approximately equivalent to O(T2). Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 200, and the models with regard to effect of J2-term have accuracies of 10-8 and the order can reach up to 280.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

Asymptotic behavior of the divergence on loop spaces over a compact Riemannian manifold

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chinese science Bulletin 1998年第4期43卷 272-274页

作者： LI Xiangdong Probability Laboratory, Institute of Applied Mathematics, chinese academy of sciences, Beijing 100080, china Probability Laboratory Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

The asymptotic behavior of the divergence on loop space is studied over a compact Riemannian manifold via quasi_sure analysis. A Sobolev estimate plays a crucial role.

关键词： divergence exponential integrability Sobolev estimate.

A template of rat brain based on fMRI T2* imaging

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Progress in Natural science:Materials International 2005年第6期15卷 502-506页

作者： HU Zhenghui1, WU Yigen2, WANG Xiaochuan3. WANG Jianzhi3. CHEN Feiyan1 and TANG Xiaowei1*(1. Department of Physics and Bio-X Laboratory, Zhejiang University, Hangzhou 3.0027, china 2. Institute of High Energy Physics and Key Laboratory of Nuclear Analysis Techniques, chinese academy of sciences,Beijing 10003., china 3. Department of Pathophysiology, Tongji Medical College, Huazhong University of {3. and Technology, Wuhan 43.03., china) Department of Physics and Bio-X Laboratory Zhejiang University Hangzhou 310027 China Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China Department of Pathophysiology Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

The development of functional magnetic resonance imaging (fMRI) technology has made it possible to carry out functional brain imaging experiments in small animals. Usually, group data is required to form the assessment of population, which can not only increase the sensitivity of the overall experiment, but also allow the generalization of the conclusion to the whole population. In order to average the signals of functional brain images from different subjects, it is necessary to put all the mapping images into the same standard space (template image). However, up to now, most animal brain templates remain unavailable and it must be done by ourselves. In this study, a template image based on the brains of eight male Wistar rats is obtained, and it is successfully used in our present Alzheimer disease (AD)-like rat model studies as template for spatially normalizing images to the same stereotaxical space. The fMRI results processed with statistical parametric mapping (SPM99) software are in agreement with the results from immunohistochemical experiment, which proves that this method is universally applicable to the pathologic models of other small animals and to human brain lesion studies.

关键词： fMRI animal model atlas template normalization T*2.

Finding Signals for Plant Promoters

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Genomics, Proteomics & Bioinformatics 2003年第1期1卷 68-73页

作者： Weimou ZhengInstitute of Theoretical Physics, chinese academy of sciences, Beijing 100080, china Beijing GenomicsInstitute, chinese academy of sciences, Beijing 1013.0, china Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China Beijing Genomics Institute Chinese Academy of Sciences Beijing 101300 China

The strongest signal of plant promoter is searched with the model of single motif with two types. It turns out that the dominant type is the TATA-box. The other type may be called TATA-less signal, and may be used in gene finders for promoter recognition. While the TATA signals are very close for the monocot and the dicot, their TATA-less signals are significantly different. A general and flexible multi-motif model is also proposed for promoter analysis based on dynamic programming. By extending the Gibbs sampler to the dynamic programming and introducing temperature, an efficient algorithm is developed for searching signals in plant promoters.

关键词： for on is as et Pro Finding Signals for Plant Promoters been of into