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Chinese Chemical Letters 2014年第6期25卷 967-972页

作者： Li-Zhuang Chen Deng-Deng Huang Qi-Jian Pan Fang-Ming Wang School of Biology and Chemical Engineering Jiangsu University of Science and Technology State Key Laboratory of coordination Chemistry School of Chemistry and Chemical EngineeringNanjing University

Reacting homochiral （R）-2-methylpiperazine with cobalt sulfate heptahydrate by the solution method in the presence of concentrated sulfuric acid （H2SO4） yielded two coordination compounds （C5H14N2） [CO（H2O）6]（SO4）2 （1 and 2）. They are polymorphs, but their hydrogen bonds structure differ significantly. Both 1 and 2 crystallize in chiral space group P21 which is related with point group C2, and experimental results suggest that 1 displays ferroelectric behaviors.

关键词： Co(Ⅱ) compound Homochiral Ferroelectric Dielectric

Hydrothermal Preparation, Crystal Structure and Properties of {[ZnTCPP（EtOH）][Zn（en）]2}n（EtOH）2n with a Novel Two-Dimensional （2-D） Motif

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Chinese Journal of Chemistry 2012年第2期30卷 273-276页

作者： Chen,Wentong School of Chemistry and Chemical Engineering Institute of Applied ChemistryJiangxi Province Key Laboratory of Coordination ChemistryJinggangshan UniversityJi'anJiangxi343009China

A novel zinc porphyrin, {[ZnTCPP（EtOH）][Zn（en）]2},（EtOH）2, （1）（TCPP=meso-tetra（4-carboxyphenyl）- porphyrin; EtOH=ethanol; en=ethylenediamine） was obtained via a hydrothermal reaction and characterized by single-crystal X-ray diffraction. Complex 1 crystallizes in the space group C2/c of the monoclinie system with eight formula units in a cell： a=32.465（4） A, b=10.527（3） A, c=31.845（3） A,β=95.524（6）°, V=10832（4） A3, C58H57NsOaIZn3, Mr= 1238.23, Dc= 1.518 g/cm3, S=1.005, μ（Mo Kα）= 1.388 mm-1, F（000）=5112, R=0.0650 and wR=0.1574. Complex 1 features a novel 2-D layered motif. The spectral data of UV-vis, FT-IR and fluorescence are reported.

关键词： crystal fluorescence hydrothermal porphyrin meso-tetra(4-carboxyphenyl)-porphyrin (TCPP)

PLF Optimization for Target Language Detection

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Chinese Journal of Electronics 2017年第1期26卷 118-121页

作者： ZHANG Jian YUAN Qingsheng BAO Xiuguo ZHOU Ruohua YAN Yonghong Institute of Information Engineering Chinese Academy of Sciences Institute of Acoustics Chinese Academy of Sciences National Computer Network Emergency Response Technical Team/coordination Center of China

The objective of traditional feature studies in Spoken language recognition(SLR) is extracting the linguistic discrimination between each language. However,applications of security area always interested in a particular language, which requires the features should be the best reflection of the differences between target language and the other languages. To address this problems, the frame level Phone log-posteriors feature(PLF), which has been recently introduced as a novel and effective feature in SLR, is optimized to get a better performance on Target language detection(TLD) task. The F-Ratio analysis method is used to analyze the contribution of each dimension in feature vector for TLD. In this work, frame level phone posterior probabilities are estimated by a phone recognizer, and processed through taking logarithm. Then the feature is optimized through weighting each dimension according to the F-Ratio values. Finally, Principal component analysis(PCA) is used to decorrelate the feature and reduce vector size. Experiments carried out on the NIST LRE 2007 dataset show that the effectiveness of the optimized feature, which yields significant relative improvements in term of Equal error rate(EER) with regard to the Gaussian mixture models-Support vector machines(GMM-SVM) system based on the original feature.

关键词： Spoken language recognition Target language detection Weighted phone log-posteriors F-Ratio

Structure and Photophysical Properties of a Chiral 4-Fold Interpenetrated Zn(Ⅱ) coordination Polymer Tuned by 4,4'-(Hexafluoroisopropylidene)bis(benzoic acid)and 1,3-Di(pyridineyl)benzene

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Chinese Journal of Structural Chemistry 2017年第2期36卷 258-265页

作者：黄新华张雷周春辉 School of Materials Science and Engineering Anhui University of Science and Technology State Key Laboratory of coordination Chemistry School of Chemistry and Chemical Engineering Nanjing University

A new three-dimensional（3D） chiral metal-organic coordination polymer, [Zn（dpb）（hfipbb）]n, was obtained under hydrothermal conditions by 1,3-di（pyridineyl）benzene（dpb） and 4,4-（Hexafluoroisopropylidene）bis（benzoic acid）（H2hfipbb）. The as-prepared sample was characterized by single-crystal X-ray diffraction, PXRD, elemental analysis, IR spectroscopy and TGA analysis. The title coordination polymer crystallizes in orthorhombic, space group P21212, with a=21.923（4）, b=23.594（4）, c=7.3042（13） , V=3778.1（12） 3, Dc=1.209 g/cm3, Mr=687.90, F（000）=1328, μ=0.713 mm（-1） and Z=4. The compound contains two types of helical chains [Zn（hfipbb）]n and [Zn（dpb）]n which are linked with each other to generate a 3D framework by sharing the same Zn（Ⅱ） cations. It displays a 4-fold interpenetrated 3D framework. In addition, the luminescence, fluorescence lifetime and the second harmonic generation（SHG） efficiency properties in the solid state have been studied.

关键词： benzoic acid benzene and 1 3-Di chains hydrothermal helical orthorhombic chiral luminescence lifetime

Synthesis and Structure of a Novel Macrocyclic Complex [Cd_2(phen)_4(phth)_2]·4H_2O

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1298-1301页

作者： SUN Ya-Guang GAO En-Jun WEI De-Zhou LIU Yi-Nan Laboratory of coordination Chemistry Shenyang Instituteof Chemical Technology Shenyang Liaoning 110142 China School of Resource ＆ Civil Engineering Northeastern University Shenyang Liaoning 110004 China

A novel complex [Cd2（phen）4（phth）2]·4H2O has been synthesized by the reaction of Hzphth（phthalic acid） and phen（1,10-phenanthroline） with Cd（Ⅱ） in ethanol-water solution. X-ray crystal structure analysis shows it crystallizes in triclinic, space group PI- with a = 10.619（3）, b = 12.560（4）, c = 12.651（4） A, a = 98.775（5）, β = 109.035（5）,γ = 113-576（5）°, C32H24CdN4O6, Mr= 672.95, V = 1381.7（7）A^3, Rint = 0.0358, Z = 2, Dc= 1.618 g/cm^3,μ = 0.845 mm^-1, -6 ≤h≤13, -15 ≤k ≤13, -15 ≤l≤14, F（000） = 680, S = 1.038, R = 0.0480 and wR = 0.0849 for 3992 observed reflections （1 〉 2σ（Ⅰ））. Phth bridges Cd（Ⅱ） to form a macrocyclic compound, and a 2D supramolecular motif is formed through hydrogen bonds and π-π interaction.

关键词： cadmium complex crystal structure hydrogen bonding π-π interaction

Predictable site-selective radical fluorination of tertiary ethers

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Science China Chemistry 2020年第2期63卷 187-191页

作者： Junyang Ma Wentao Xu Jin Xie State Key Laboratory of coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation CenterSchool of Chemistry and Chemical EngineeringNanjing University

In this communication,we disclose the first example of metal-free and site-selective radical fluorination of readily available tertiary alkyl ethers,enabled by synergistic photocatalysis and *** catalytic combination allows for exclusive fluorination of tertiary C–O bonds under mild conditions even in the presence of competing reaction *** excellent functional group tolerance affords valuable access to sterically hindered alkyl fluorides through late-stage modification of complex *** successful use of tertiary alkyl ethers in radical fluorination enhances the structural diversity of aliphatic fluorides that can be derived from naturally abundant alcohols.

关键词： cooperative catalysis C–O bond activation radical fluorination polarity-matching effect umpolung

As-Rigid-As-Possible Surface Morphing

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Journal of Computer Science & Technology 2011年第3期26卷 548-557页

作者：刘亚姝严寒冰 Ralph R.Martin Department of Computer Science Beijing University of Civil Engineering and Architecture National Computer Network Emergency Response Technical Team/coordination Center of China School of Computer Science Cardiff University

This paper presents a new morphing method based on the ＂as-rigid-as-possible＂ approach. Unlike the original as-rigid-as-possible method, we avoid the need to construct a consistent tetrahedral mesh, but instead require a consistent triangle surface mesh and from it create a tetrahedron for each surface triangle. Our new approach has several significant advantages. It is much easier to create a consistent triangle mesh than to create a consistent tetrahedral mesh. Secondly, the equations arising from our approach can be solved much more efficiently than the corresponding equations for a tetrahedral mesh. Finally, by incorporating the translation vector in the energy functional controlling interpolation, our new method does not need the user to arbitrarily fix any vertex to obtain a solution, allowing artists automatic control of interpolated mesh positions.

关键词： morphing simplex transformation interpolation

Synthesis, Crystal Structure and Properties of a New Zn(II) coordination Polymer Constructed from 2,3-Pyridine Dicarboxylic Acid and 1,1′-(1,4-Butanediyl)bis(imidazole)

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Chinese Journal of Structural Chemistry 2014年第2期33卷 193-198页

作者：李书静李可曲波涛郑玮 Department of Chemistry Zhoukou Normal University State Key Laboratory of coordination Chemistry School of Chemistry and Chemical EngineeringNanjing National Laboratory of Microstructures Nanjing University

A new coordination polymer, namely [Zn（pdc）（bbi）]n {H2 pdc = 2,3-pyridine dicar- boxylic acid, bbi = 1,1-（1,4-butanediyl）bis（imidazole）}, has been prepared under hydrothermal conditions and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group P21 /n with a = 8.436（3）, b = 16.988（5）, c = 12.106（4）, β = 92.204（5）°, V = 1733.6（9）3, Z = 4, C17 H17 N5 O4 Zn, Mr = 420.73, Dc = 1.612 g/cm3, F（000） = 864, μ（MoKa） = 0.452 mm-1, the R = 0.0672 and wR = 0.1645. In the mononuclear complex, each Zn（II） is five-coordinated by one carboxylate O and one pyridyl N atoms from one pdc anion, one carboxylate O atom from another pdc anion, and two N atoms from two bib ligands. The Zn（II） ions are connected by pdc ligands to form skeleton chains, and bbi ligands further link them to construct a 2D framework. The thermal and luminescence properties of the complex were also investigated.

关键词： 2,3-pyridine dicarboxylic acid 1,1'-(1,4-butanediyi)bis(imidazole),zinc complex crystal structure thermal analysis luminescence

A colorimetric and ratiometric fluorescent chemosensor based on furan-pyrene for selective and sensitive sensing Al^(3+)

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Chinese Chemical Letters 2016年第11期27卷 1673-1678页

作者： Yuan Zhang Yuan Fang Nai-Zhang Xu Ming-Qun Zhang Guan-Zhi Wu Cheng Yao College of Chemistry and Molecular Engineering Nanjing Tech University College of Overseas Education Nanjing Tech University State Key Laboratory of coordination Chemistry Nanjing University

A new pyrene derivative BF bearing a furan group was synthesized via a one-step reaction as a colorimetric and ratiometric chemosensor for Al3＋ in ethanol-H20 （9：1, v/v, pH 7.2, HEPES buffer） solution. This chemosensor could selectively recognize Al3＋ in the presence of other competing ions. Low limit of detection （LOD） and high association constant revealed its superior sensitivity and binding affinity toward Al3＋, Besides, the probe BF performed perfectly in a reversibility test using EDTA. The mechanism of the interaction has been confirmed by 1H NMR titration. Importantly, chemosensor BF has also been utilized to detect Al3＋ on test paper strips, which showed its ootential for practical applications.

关键词： Pyrene Al3+ Colorimetric Ratiometric Chemosensor Application

One and Two-dimensional Structures of a New Oxamido Copper(II) Complex with Phthalato Bridged

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Chinese Journal of Structural Chemistry 2005年第9期24卷 1017-1020页

作者：陈静姜宗慧廖代正闫世平 Department of Chemistry Nankai University Tianjing 300071 China Department of Chemistry Nankai University Tianjing 300071 China State Key Laboratory of Coordination Chemistry Nanjing 210093 China

A new o-phthalato-bridged oxamide copper（Ⅱ） complex 1, {[Cu2（oxap）]（pht）. 4H2O}n （oxap=N, N＇-bis（2-aminopropyl）oxamide, pht= phthalate dianion）, has been prepared and structurally characterized. It crystallizes in monoclinic, space group C2/c with a=23.424（4）, h=7.9696（14）, c=15.727（3）A°,β=129.617（2）°, C16H28Cu2N4O10, Mr=563.50, V=2261.6（7） A°, Z=4, Dc=1.655 g/cm^3, μ（MoKα）=1.939 mm^-1, F（000） = 1160, the final R=0.0393 and wR=0.0928 for 1707 observed reflections with I〉2σ（1）. Single-crystal X-ray analysis reveals that 1 displays a one-dimensional zigzag chain structure, in which each Cu（oxap） moiety adopting trans-conformation is connected by ,μ1,6-phthalate anion bridges, and these zigzag chains are further linked by another ,μ1,6-phthalate anion bridge to form a 2D sheet structure. The polar guest water molecules reside in the inter-and intrasheets to stabilize the whole crystal structure.

关键词： phthalate oxamide bridged copper(Ⅱ) complex crystal structure host-guest