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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 chemical Physics, Beijing Institute of Technology, Beijing 100081, china 2. chemical Industry Press, Beijing 100029, 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 (2002—2004) 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.

Study on the Inert Coordination Compound in the System of“Molybdenum(Ⅵ)—TAE—Hydroxylamine”and its Analytical Application

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Rare Metals 1989年第2期9卷 58-63页

作者： Chen Huaxu Shao Guangdi department of Chemistry,University of Science and Technology BeijingBai Linshan department of chemical Engineering,East china Institute of Metallurgy

In the presence of ethyl alcohol or emulsifier OP,molybdenum(Ⅵ) forms 1∶1∶1'water soluble colored coordination com- pound with both of 2-(2-thiazolylazo)-5-diethylaminophenol (abbreviation TAE) and *** deep blue coordination compound is inert characteristically and remains stable in 1.7 mol/L sulfuric acid,2.4 mol/L hydrochloric or ni- tric *** will not be decomposed by masking agents even on boiled,while in that case,almost all the colored coordination com- pounds formed by other metal ions will be decomposed *** inert character of the coordination compound of molybdenum(Ⅵ) and its utilization in improving the analytical selectivity have been *** the coexistence of various for- eign ions,especially in the presence of a great quantity of tungsten,which always interferes with the determination of molybdenum,the direct determination of molybdenum in the aqueous solution by applying this system has shown an acceptable sensitivity and *** the results of determination in some synthetic and standard samples,it seems feasible to use this system in the determination of molybdenum in nonferrous alloys.

关键词： and its Analytical Application Molybdenum Hydroxylamine Study on the Inert Coordination Compound in the System of TAE

Concise synthesis of two advanced intermediates for the asymmetric synthesis of polyhydroxylated indolizidine alkaloids

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Science china Chemistry 2010年第9期53卷 1914-1920页

作者： ZHENG Xiao1,2,ZHU WenFang1 & HUANG PeiQiang1 1department of Chemistry,College of Chemistry and chemical Engineering,Xiamen University,Xiamen 361005,china 2Key Laboratory of synthetic Chemistry of Natural Substances Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,Shanghai 200032,china 1. department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. Key Laboratory of Synthetic Chemistry of Natural Substances Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

A concise five-step approach to indolizidinones 10 and 11,two advanced intermediates for the asymmetric synthesis of polyhydroxylated indolizidine alkaloids,has been developed by using N-Cbz pyrrolidin-2-yl pyridin-2-yl sulfide 13 as the chiral building *** method features a SmI2-mediated coupling of sulfide 13 with functionalized aldehyde 14 and a tandem N-deprotection-lactamization,which constitutes a stepwise "2 + 4" annulation method for the construction of the indolizidinone ring system of 12a.

关键词： indolizidinone samarium diiodide α-amidohydroxyalkylation tandem reaction chiral building block

Molecular architecture and engineering of spider dragline silk protein

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Progress in Natural Science:Materials International 2005年第9期15卷 769-776页

作者： ZHANG Hengmu and LIU Jinyuan(department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, china) department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

Spider dragline silk, which is produced in spider major ampullate gland, is a composite proteinacious fiber with highly repetitive Ala-Gly-rich domain. The unique combination of both high tensile strength and high elasticity makes spider dragline silk superior to almost any other natural or synthetic fibers. Cloning of the genes reveals that the silk is composed of at least two major proteins. Each protein component contains multiple repeats of modular structures that alternate between Ala-rich domains and Gly-rich domains. Molecular engineering not only opens a door to the production of spidroins but also provides a valuable experimental system to test and further establish the relationship between modular structures and mechanical properties. Here, based on our own studies, we review the latest progress of the modular structure and genetic engineering and outline the future prospects.

关键词： spider dragline silk protein modular structure molecular engineering.

physically based simulation of Buddha Glory

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Progress in Natural Science:Materials International 2006年第6期16卷 656-662页

作者： LIU Shiguang, WANG Zhangye, GONG Zheng, WANG Changbo and PENG Qunsheng (State Key Laboratory of CAD&CG, Zhejiang University, Hangzhou 310027, china department of Mathematics, Zhejiang University, Hangzhou 310027, china department of Structure Engineering, Tongji University, Shanghai 200092, china) [a]State Key Laboratory of CAD&CG Zhejiang University Hangzhou China [b]department of Mathematics Zhejiang University Hangzhou China [c]department of Structure Engineering Tongji University Shanghai China

This paper proposes a novel method of photorealistic simulation of Buddha Glory, a natural phenomenon of great visual beauty which can be observed in the area of famous Buddhism Holy Lands in china. This phenomenon is mainly caused by back-scattering of water droplets in fog or cloud. To simulate the glory, we first calculate the spectral scatter intensity of glory rings using Mie scattering theory. We then present a new shadow model to determine the deformed shape of the head and body of "Buddha" within the glory ring. The affect of atmospheric parameters such as the solar elevation angles, the density and size of water droplet in fog or cloud on the shape and color of Buddha Glory is also calculated. For rendering, we adopt the method of path scattering integral to generate the whole attenuated scene of Buddha Glory. Compared with the photographs of real Buddha Glory displays, our synthetic results are quite satisfactory.

关键词： natural phenomenon Buddha Glory back-scattering physically based simulation.

Approach to synthesis of novel chiral 3-chloro-2(5H)- furanone and its application in asymmetric reactions

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Chinese Science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. department of Chemistry, Tonghua Teacher’s College, Tonghua 134002, china 2. department of Chemistry, Beijing Normal University, Beijing 100875, china department of Chemistry Tonghua Teacher’s College Tonghua China department of Chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2,3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3-chloro-2-(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.

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

Cytotoxic T lymphocyte response induced by an improved synthetic lipopeptide vaccine against cervical cancer

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Acta Pharmacologica Sinica 2007年第5期28卷 695-702页

作者： Dao-hua XU~(1,5),Chen-hui ZHOU~2,Yong-peng XIA~3,Zong-ying QIU~3,Yu-zhang WU~4,Zheng-cai JIA~4,Wei ZHOU~4~1 department of Pharmacology and ~2 School of Nursing,Guangdong Medical College,Zhanjiang 524023,china ~3 department of PharmacyChongqing University of Medical Science,Chongqing 400016,china,~4 Institute of Immunology PLA,Third Military Medical University,Chongqing 400038,china departmentofPharmacology SchoolofNursing GuangdongMedicalCollegeZhanjiang524023China departmentofPharmacy ChongqingUniversityofMedicalScienceChongqing400016 InstituteofImmunology PLAThirdMilitaryMedicalUniv

Aim:To explore cytotoxic T lymphocyte （CTL） response induced by the lipopeptidevaccine against cervical ***:The immunological effect inducingCDS+ T cell-mediated cytotoxicity was investigated in human leukocyte antigen（HLA）-A2 transgenic mice and peripheral blood mononuclear cells （PBMC） ofhealthy HLA-A2.1+blood *** activity of specific CTL was measured byusing a standard 4 h51Cr release *** content of major histocompatibilitycomplex （MHC） I on T2 cells and the expression of immune molecules on dendriticcells （DC） were detected by flow cytometry,and the concentrations of interleukin（IL）-12 and interferon-γ were determined by ***:The lipopeptideinduced a strong epitope-specific CTL response both in vivo （transgenic mice）and in vitro （human PBMC）.This CTL induction was critically dependent on thepresence of the helper T lymphocyte epitope in transgenic mice,and the presenceof a lipid tail bypassed the need for an *** stability and persistence ofthe antigenic complex formed with the lipopeptide increased in comparison withthe CTL parental *** lipopeptide could induce the production of IL-12 inDC,but not the maturation of DC ***:The combination of CTLand the T helper epitope and lipid molecule can remarkably improve the immuno-genicity of the CTL peptide,the mechanism of which is associated with an in-crease in the stability and persistence of the antigenic complex formed with thelipopeptide and in the production of IL-12 in DC induced by the *** can be considered a more effective vaccine type for human being.

关键词： epitope cervical cancer lipopeptide vaccine

Estimating fisheye camera parameters from homography

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Science china(Information Sciences) 2012年第9期55卷 2119-2127页

作者： ZHU HaiJiang 1,YANG Ping 2 & LI ShiGang 3 1 School of Information Science and Technology,Beijing University of chemical Technology,Beijing,100029,china 2 National Institute of Metrology,100013,Beijing,china 3 department of Electrical and Electronic Engineering,Tottori University,680-8552,Koyama,Tottori,Japan 1. School of Information Science and Technology Beijing University of Chemical Technology Beijing 100029 China2. National Institute of Metrology 100013 Beijing China3. Department of Electrical and Electronic Engineering Tottori University 680-8552 Koyama Tottori Japan

This paper presents a method to linearly estimate fisheye camera model parameters from the homography induced by the space plane between two fisheye *** homography is firstly calculated by using four feature points,instead of three points on the same line,in the fisheye *** the constraint on the model parameters of fisheye camera can be derived from the homography under the assumption that fisheye camera model is a polynomial *** the model parameters for different order polynomials are *** proposed technique requires only multiple fisheye images to include a planar scene and need not a priori knowledge of 3D coordinate of the planar *** results with synthetic data and real fisheye images demonstrate the validity of our *** method can also be extended to fisheye image of other planar scene excluding the planar calibration object.

关键词： homography parameter estimation fisheye camera