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SYNTHESIS OF NOVEL LIQUID CRYSTALLINE POLY(METH)ACRYLATES CONTAINING SILOXANE SPACER AND TERPHENYLENE MESOGENIC UNIT

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Chinese Journal of Polymer Science 2000年第2期18卷 101-107页

作者： Zhi-qian Zang Yu-fei Luo Dong Zhang Xin-hua Wan Qi-feng Zhou Department of Polymer Science & Engineering, College of Chemistry, Peking University, Beijing 100871, China 北京大学北京

Novel side-chain liquid-crystalline poly(meth)acrylates were synthesized using 1-(3-hydroxyl-propyl)-3-[(4 '-cyano-p-terphenyloxycarbonyl)alkyl]-1,1,3,3-tetramethyldisiloxane as the key intermediate. The polymers used a disiloxane moiety as decoupling spacer with cyano-p-terphenyl as mesogenic unit. The products were characterized by NMR, GPC, DSC and polarizing optical microscopy. All the polymers with cyano-p-terphenyl mesogens formed a stable mesophase. However, if the mesogenic unit is replaced by cyano-p-biphenyl, the liquid crystalline character will be lost. The results also showed that the decoupling is incomplete even if a complex and very flexible decoupling spacer is deliberately incorporated to obtain the highest possible decoupling effect.

关键词： liquid crystalline polymers polyacrylates 4 ''-cyano-p-terphenyl

FULLY COUPLED FORWARD-BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS WITH GENERAL MARTINGALE

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Acta Mathematica Scientia 2006年第3期26卷 443-450页

作者：李娟 School of Mathematical Sciences Fudan University Shanghai 200433China Department of MathematicsShandong University at WeihaiWeihai 264200China

The article first studies the fully coupled Forward-Backward Stochastic Differential Equations （FBSDEs） with the continuous local martingale. The article is mainly divided into two parts. In the first part, it considers Backward Stochastic Differential Equations （BSDEs） with the continuous local martingale. Then, on the basis of it, in the second part it considers the fully coupled FBSDEs with the continuous local martingale. It is proved that their solutions exist and are unique under the monotonicity conditions.

关键词： Backward stochastic differential equations local martingale predictable representation property of martingale

Synthesis and Crystal Structure of N-(5-Phenylseleno)pentyl Succinimide

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Chinese Journal of Structural Chemistry 2002年第5期21卷 517-519页

作者：张万轩于海涛等 DepartmentofChemistry NankaiUniversityTianjin300071China

N-(5-phenylseleno)pentyl succinimide 1, C15H19NO2Se (Mr = 324.27), was prepared by treating Br(CH2)5SePh with potassium succinimide. Its crystal structure has been determined by X-ray single-crystal diffraction. The crystal of 1 belongs to monoclinic system, space group P21/c with the crystal cell parameters: a = 18.018(6), b = 5.980(2), c = 14.682(5) ? = 109.977(6)? V = 1486.7(9) 3, Z = 4, Dc = 1.449 g/cm3, (MoK? = 2.523 mm-1, F(000) = 664,the final R = 0.0302 and wR = 0.0666 for 2623 independent observed reflections with I > 2(I). Structure analyses revealed that there exist strong nonclassical hydrogen bonds (CH…O).

关键词： N-(5-苯基硒基)戊烷基琥珀酰亚胺合成晶体结构 C15H19NO2Se

Synthesis and Crystal Structure of an Ion-pair Supramolecular Associate 2,9-Diformyl-1,10-phenanthrolinebis-(2,6-dimethylanil)cobalt(Ⅱ) Perchlorate

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Chinese Journal of Structural Chemistry 2006年第7期25卷 861-865页

作者： LI Gang JIE Su-Yun TANG Ning SUN Wen-Hua State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China Key Laboratory of Engineering Plastics Institute of Chemistry The Chinese Academy of Sciences Beijing 100080 China

2,9-Diformyl-l, 10-phenanthrolinebis（2,6-dimethylanil）cobalt（Ⅱ） perchlorate was synthesized and demonstrated to be [COL2][ClO4]2 by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group C2/c with a = 22.294（4）, b = 15.122（3）, c = 20.640（4） A, β = 119.618（4）°, V = 6048.9（19） A^3, C63H52Cl2CoN9O9, Mr= 1208.97, F（000） = 2504, De= 1.328g/cm^3, Z = 4, μ= 0.436, the final R = 0.0712 and wR = 0.1718 for 1734 observed reflections （I 〉 2σ（I））. In its solid state the helical polymeric chains are supramolecularly associated through intermolecular and interionic hydrogen bonding interactions.

关键词： 1,10-phenanthroline cobalt complex crystal structure hydrogen bond

Synthesis and Crystal Structure of 7α-[(R)-1-Hydroxyl-1-methyl-3-(thien-2-yl)- propyl]-6,14-endoethanotetrahydrothebaine

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Chinese Journal of Structural Chemistry 2005年第9期24卷 1021-1024页

作者：刘河刘春河吴波陈兰福仲伯华 No. 7 Department Beijing Institute of Pharmacology and Toxicology Beijing 100850 China

The crystal structure of 7α-[（R）-1-hydroxyl-1-methyl-3-（thien-2-yl）propyl]-6,14-endoethanotetrahydrothebaine （C29H37NO4S, Mr=495.66） has been determined by single-crystal X-ray diffraction analysis. The crystal belongs orthorhombic, space group P212121 with α=10.063（4）, b=12.571（5）, c=19.626（8）A°, V=2482.9（17）A°^3, Z=4, Dc=1.326 g/cm^3,μ=0.167 mm^-1, F（000）=1064, the final R=0.0537 and wR=0.0888. The C（7） substituent is l-hy-droxyl-1-methyl-3-（thienyl-2-）propyl group adopting R-configuration. The N-methyl group is located at the equatorial position as expected. The crystal structure shows the presence of intra- molecular hydrogen bonds, O（1）-H（1）…O（2）.

关键词： thebaine crystal structure grignard reaction

A Series of Lanthanide-organic Frameworks Constructed by Ln_4(OH)_4 Clusters and Mixed Ligands

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Chinese Journal of Structural Chemistry 2019年第1期38卷 103-108,4页

作者：顾翔宇金聪聪程建文 Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical Chemistry Zhejiang Normal University

Three new lanthanide-organic compounds, namely, [Ln_2(OH)_2(oba)(2-pc)_2]n(Ln =Er(1), Ho(2), and Dy(3))(oba = 4,4?-oxybis(benzoate), 2-pc = 2-pyrazinecarboxylic acid) have been obtained under hydrothermal conditions. These compounds are isostructural and exhibit 2 D layered structures by incorporating [Ln_4(μ_3-OH)_4]^(8+) clusters and the mixed linkers of oba and 2-pc. It is interesting that decarboxylation occurred in the ortho position and 2,3-pyrazinedicarboxylic acid was partially transformed into 2-pc under hydrothermal conditions. Compound 3 emits a typical Dy^(3+) emission spectrum. Furthermore, the PXRD, TGA and IR spectra were also studied.

关键词： lanthanide cluster mixed ligands luminescence

Synthesis of α-Arylated Esters from Aryl Halides

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Chinese Chemical Letters 2006年第5期17卷 595-598页

作者： Wei DENG Ye Feng WANG Lei LIU Qing Xiang GUO Department of Chemistry University of Science and Technology of China Hefei 230026

An operationally simple and inexpensive catalyst system was developed for the cross coupling of aryl iodides and bromides with ethyl acetoacetate by using CuI as catalyst and Nmethyl glycine as ligand. The reaction represents a novel Cu-catalyzed C-C cross coupling reaction. This procedure is applicable to the preparation of pharmaceutically important α- arylalkanoic acids.

关键词： Cross coupling reaction CuI ethyl acetoacetate aryl halide α-arylalkanoic acids.

Kinetic Study on Horseradish Peroxidase Interacting with Cyclodextrin

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Chinese Chemical Letters 2000年第8期11卷 721-724页

作者： Chen, JB Xia, CG Ben Li, S Chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Oxo Synth & Select Oxidat Lanzhou 730000 Peoples R China

The catalyst reactivity of Horseradish peroxidase was enhanced in the presence of beta-cyclodextrin. During this course, beta- cyclodextrin played a role of stabilizing the intermediates of HRP. The results have been ... 详细信息

关键词： horseradish peroxidase beta- cyclodextrin compound kinetics

TESTING OF CORRELATION AND HETEROSCEDASTICITY IN NONLINEAR REGRESSION MODELS WITH DBL(p,q,1) RANDOM ERRORS

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Acta Mathematica Scientia 2008年第3期28卷 613-632页

作者：刘应安韦博成 College of Information Science and Technology Nanjing Forestry University Department of Mathematics SoutheastUniversity

Chaos theory has taught us that a system which has both nonlinearity and random input will most likely produce irregular data. If random errors are irregular data, then random error process will raise nonlinearity （Kantz and Schreiber （1997））. Tsai （1986） introduced a composite test for autocorrelation and heteroscedasticity in linear models with AR（1） errors. Liu （2003） introduced a composite test for correlation and heteroscedasticity in nonlinear models with DBL（p, 0, 1） errors. Therefore, the important problems in regression model axe detections of bilinearity, correlation and heteroscedasticity. In this article, the authors discuss more general case of nonlinear models with DBL（p, q, 1） random errors by score test. Several statistics for the test of bilinearity, correlation, and heteroscedasticity are obtained, and expressed in simple matrix formulas. The results of regression models with linear errors are extended to those with bilinear errors. The simulation study is carried out to investigate the powers of the test statistics. All results of this article extend and develop results of Tsai （1986）, Wei, et al （1995）, and Liu, et al （2003）.

关键词： DBL(p q 1) random errors nonlinear regression models score test heteroscedasticity correlation