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On the studies of the vibrational spectra of cluster [Mo2O2S2（S2）2]2-

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Chinese Journal of Chemistry 1986年第1期4卷 42-47页

作者： liang Ying-Qiu ZHAO Wen-Yun XU Wei-Qing ZHANG Zhi-Gui Institute of Theoretical Chemistry, jilin University, Changchun, China Department of Chemistry, jilin University, Changchun, China Institute of Theoretical Chemistry Jilin University Changchun China Department of Chemistry Jilin University Changchun China

IR and Raman spectra of [Mo2O2S2（S2）2]2-were reported. The resonance Ramanspectra and the depolarization ratios in CH3CN solution were measured. By using the data of crystalstructure, the simplified normal coordinate calculation of the stretching vibrations for anion[Mo2O2S2（S2）2]2-was performed. The results obtained are useful to assign the vibrational bands ofsome Mo-Fe-S clusters.

关键词： Mo2O2S2 On the studies of the vibrational spectra of cluster

The pH Effect on Resonance Raman Spectra of Brilliant Yellow in Aqueous and CTAB Micella Solutions

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Chemical Research in Chinese Universities 1990年第3期6卷 233-235页

作者： Zhang Yunhong, Tian Yongchi and liang Yingqiu (Institute of Theoretical Chemistry, jilin University, Changchun)

Recently, we have developed an application of molecular spectrometric method to the exploration of the interracial properties of black soap films, using an azobenzene dye as a probe. In order to further study the problems of surface potential and microenvfronment, an effort should be made to clarify the pH controlled behavior of the structural change of azobenzene compounds in aqueous solution and on the surface of surfactant mlcella. Here, we examine the resonance Raman spectra of brilliant yellow(BY), an azobenzene derivative, in aqueous and cetyltrimethylammonium bromide(CTAB) micella

关键词： Brilliant yellow Raman Spectra Micella surface

Fourier Transform Infrared Study on the Melting Phase Transition of Octadecanoic Acid

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Chemical Research in Chinese Universities 1991年第1期7卷 42-46页

作者： Jiang Yutao, Tian Yongchi liang Yingqiu (Institute of Theoretical Chemistry, jilin University, Changchun)

Fourier transform Infrared (FT-IR) spectroscopy was used to study the melting phase transition of anhydrous octadecanoic acid. The phase transition occurs at 69℃(Tc). In solid phase, the alkyl chains take the all-trans zigzag conformation and the C(?)-C(?)= 0 group adopts trans configuration in the dimers. In liquid state, the alkyl chains convert to gauche conformation and the C(?)C(?)= 0 to cis configuration.

关键词： FT-IR Phase transition Octadecanoic acid

Canonical Huffman code based full-text index

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Progress in Natural Science:Materials International 2008年第3期18卷 325-330页

作者： Yi Zhang a,b, Zhili Pei a, Jinhui Yanga, Yanchun liang a, a College of Computer Science and Technology, jilin University, Key Laboratory of Symbol Computation and Knowledge Engineering of the Ministry of Education, Changchun 130012, China b Department of Computer Science, jilin Technology and Business College, Changchun 130062, China College of Computer Science and Technology Jilin University Key Laboratory of Symbol Computation and Knowledge Engineering of the Ministry of Education Changchun 130012 China Department of Computer Science Jilin Technology and Business College Changchun 130062 China

Full-text indices are data structures that can be used to find any substring of a given string. Many full-text indices require space larger than the original string. In this paper, we introduce the canonical Huffman code to the wavelet tree of a string T[1. . .n]. Compared with Huffman code based wavelet tree, the memory space used to represent the shape of wavelet tree is not needed. In case of large alphabet, this part of memory is not negligible. The operations of wavelet tree are also simpler and more efficient due to the canonical Huffman code. Based on the resulting structure, the multi-key rank and select functions can be performed using at most nH0 + jRj(lglgn + lgn lgjRj)+O(nH0) bits and in O(H0) time for average cases, where H0 is the zeroth order empirical entropy of T. In the end, we present an efficient construction algorithm for this index, which is on-line and linear.

关键词： Full-text index Su?x automaton Canonical Hu?man code

The quantum chemistry study on the electronic properties of conductive polymers of polypyridinopyridine series

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Chinese Journal of Chemistry 1994年第3期12卷 206-212页

作者： XIE, De-Min SU, Zhong-Min SHI, Zhong-liang WANG, Rong-ShunDepartment of Chemistry, Northeastern Normal University, Changchun, jilin 130024, China Department of Chemistry Northeastern Normal University Changchun Jilin 130024 China

The molecular structures of thermally structurized polyacrylonitrile (PAN), that is, polypyridinopyridine (PPyPy) series have been investigated by using quantum chemistry semiem-pirical MNDO, CNDO/2-CO methods. The changing regularities of structural stability and electronic properties are pointed out. The analyses of the energy band structures indicate that the energy gaps will become smaller, intrinsical conductivities will increase when the quasi-one-dimentional (1D) series of PPyPy molecule widen toward two-dimention (2D), which is consistent with the experimental results of polymerization degree (PD) and electrical conductivity increase with the increasing of pyrolyzed temperature.

关键词： Polypyridinopyridine conductivity electronic property.

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麦味地黄口服液防腐剂及溶剂残留量研究

药品评价 2024年第8期21卷 930-935页

作者：梅赞段玮于潜梁基琳吉安市食品药品检验检测中心江西吉安343000

目的建立麦味地黄口服液中防腐剂(苯甲酸、山梨酸)及溶剂残留量(甲醇、乙醇)的检查和评价方法,为麦味地黄口服液质量安全评价提供技术支持。方法甲醇和乙醇残留量的检查采用6%(V/V)氰丙基苯基-94%(V/V)二甲基聚硅氧烷(DB-624)为固定液... 详细信息

目的建立麦味地黄口服液中防腐剂(苯甲酸、山梨酸)及溶剂残留量(甲醇、乙醇)的检查和评价方法,为麦味地黄口服液质量安全评价提供技术支持。方法甲醇和乙醇残留量的检查采用6%(V/V)氰丙基苯基-94%(V/V)二甲基聚硅氧烷(DB-624)为固定液的毛细管柱(30 m×0.32 mm×1.8μm);程序升温;进样口温度为200℃;FID检测器温度为250℃;载气氮气流速为2.0 mL/min;顶空分流进样,分流比20∶1。苯甲酸和山梨酸的检测采用Agilent Eclipse XDB-C18色谱柱(250 mm×4.6 mm,5μm);以乙腈-0.1%磷酸溶液为流动相,梯度洗脱;流速1.0 mL/min;苯甲酸和山梨酸检测波长分别为230 nm、260 nm;柱温30℃。结果建立的方法线性、专属性、稳定性、重复性良好。对6家企业生产的15批次麦味地黄口服液进行检测,结果有1家企业的3批次样品乙醇残留量超标。结论所建立的方法准确、专属性强,此方法可用于麦味地黄口服液的质量安全评价。

关键词：麦味地黄口服液顶空-气相色谱溶剂残留液相色谱苯甲酸山梨酸

Photoluminescence Studies on Ferric Oxide Ultrafine Particles

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Chemical Research in Chinese Universities 1994年第2期10卷 146-148页

作者： ZHANG Yan AI Xi-cheng XIAO liang-zhip FEI Hao-sheng and LI Tie-jin (Department of Chemistry , Department of Physics, jilin University,Changchun, 130023 )

ＰｈｏｔｏｌｕｍｉｎｅｓｃｅｎｃｅＳｔｕｄｉｅｓｏｎＦｅｒｒｉｃＯｘｉｄｅＵｌｔｒａｆｉｎｅＰａｒｔｉｃｌｅｓＺＨＡＮＧＹａｎ；ＡＩＸｉ－ｃｈｅｎｇ；ＸＩＡＯＬｉａｎｇ－ｚｈｉｐ；ＦＥＩＨａｏ－ｓｈｅｎｇ；ａｎｄＬＩ... 详细信息

ＰｈｏｔｏｌｕｍｉｎｅｓｃｅｎｃｅＳｔｕｄｉｅｓｏｎＦｅｒｒｉｃＯｘｉｄｅＵｌｔｒａｆｉｎｅＰａｒｔｉｃｌｅｓＺＨＡＮＧＹａｎ；ＡＩＸｉ－ｃｈｅｎｇ；ＸＩＡＯＬｉａｎｇ－ｚｈｉｐ；ＦＥＩＨａｏ－ｓｈｅｎｇ；ａｎｄＬＩＴｉｅ－ｊｉｎ（Ｄｅｐａｒｔｍｅｎ...

关键词： Ultrafine particles Quantum size effect Surface modification Photo-luminescence

Configuration Reversion of the Metal Chelates of N-hydroxyethyl Ethylenediaminetriacetic Acid——Dynamic NMR Study

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Chemical Research in Chinese Universities 1992年第2期8卷 129-131页

作者： LI Fei, SONG Rui-fang and LI liang (Institute of Theoretical Chemistry, jilin University, Changchun, 130023)

The intramolecular acetate rearrangement of the aminocarboxylate metal chelates with the hexdentate-coordinate has been investigated by dynamic NMR in recent years. However, the intramolecular processes of the metal q... 详细信息

关键词： Intramolecular rearrangement Mechanism Dynamic NMR Metal che-late Quinquedentate HEDTA ligand

Synthesis and Structure Study of Molybdenum Complex Mo[o-NHCOCH_3-m-NO_2C_6H_3COOH]_2_O2Cl_2·PhCl

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Chemical Research in Chinese Universities 1990年第2期6卷 124-129页

作者： Wu Lixin and Fan Yuguo(The Institute of Theoretical Chemistry, jilin University, Changchun)Guo Chunxiao, Sun Chunting, Huang Qijun, liang Tianfei and Zhang Jingwen(Department of Chemistry, jilin University, Changchun)

The crystal and molecular structures of molybdenum complex, Mo [ o- NHCOCH3- m-NO2C6H3COOH]*** are reported. The crystal belongs to space group Cc of monoclinic system with unit cell parameters:α= 11. 214 (3) A .b= 19. 544 (4 ) A . c = 14. 091 (6) A .β=94.06(3)°,V'=3080.3 A3 and Z=4. The structure was refined to R=0. *** coordination number for the Mo atom Is six. The coordination polyhedron formed by four O atoms and two Cl atoms around the Mo atom is a distorted octahedron. Four O atoms and one Mo atom construct a plane. Two benzyl planes in coordinate groups and the benzyl plane of solvent are almost parallel. The quantum-chemical calculations were carried out. There are hydrogen bonds in the Complex. The EHMO calculations and the existence of hydrogen bonds prove that the O atoms are stronger coordinated atoms in the carbonyls than in the carboxyls.

关键词： Molybdenum complex Synthesis Structure Coordination