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A spectral study of the interaction between chelerythrine chloride and cytidine

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Chinese Chemical Letters 2007年第6期18卷 722-725页

作者： Xiao Yan Zhang Quan Ling Suo xiong hui wei Department of Applied Chemistry College of Chemistry & Molecular Engineering Peking University Beijing 100871 China Department of Chemical Engineering Inner Mongolia University of Technology Huhhot 010042 China

To study the possible anticancer mechanisms of chelerythrine (CHE), and its interactions with cytidine were investigated by UV–vis spectrophotometric and spectrofluorimetric measurements and by thermodynamic calculations. The binding of CHE to cytidine could be characterized by the hypochromic and bathochromic effects in the absorption bands, and the quenching of fluorescence intensity. The spectral data were fit by linear analysis, yielding a binding constant of 2.49 × 10(4) L mol(?1)at 25 °C of CHE and cytidine, and a van’t Hoff enthalpy of ?20.02 kJ/mol for the exothermic interaction in the standard state. In addition, with and , the interactions should be entropy-driven.

关键词： Chelerythrine Cytidine Fluorescence quenching UV Thermodynamic

Spectral studies of the interaction between sanguinarine and guanosine

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Chinese Chemical Letters 2008年第12期19卷 1465-1469页

作者： Zuo Peng Du Quan Ling Suo Xiao Yan Zhang Ling wei Zhang xiong hui wei Chemical Engineering College Inner Mongolia University of Technology Hohhot 010051 China Department of Applied Chemistry Peking University Beifing 100190 China Beifing Boyuan-Hengsheng High-Technology Co. Ltd. Beijing 100190 China

The interaction between sanguinarine and guanosine was investigated by using UV-vis and fluorescence spectra at pH 7.2. The binding of sanguinarine to guanosine was substantiated by the hypochromism and bathochromism in the absorption spectra and the emission quenching in fluorescence spectra. The fluorescence lifetime results, the varieties of the fluorophore absorption spectra and the decrease of the binding constant with the increasing temperature all indicate that the fluorescence quenching is static. The ratio and constant of the binding cytidine to sanguinarine are 2 and 6.44 × 10^7, respectively. The result shows that the binding of sanguinarine to guanosine is not only exothermic but also entropy-driven with △H=-8.53kJ/mol, AS = 0.12 kJ/（molK）, and AG =-44.57 kJ/mol at 298.15 K.

关键词： Sanguinarine Guanosine Spectroscopy Interaction

Synthesis and Characterization of Cerium Tetraphenylporphyrin Nitrate and Molecular Recognition for NO

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Chinese Journal of Chemical Physics 2014年第3期27卷 302-306页

作者： Qiu-xia Xua Jian-bin Zhang Tian-xiang Zhao Gong-jia Lan xiong-hui wei College of Chemical Engineering Inner Mongolia University of Technology Huhhot 010051 China Department of Applied Chemistry College of Chemistry and Molecular Engineering PekinE University Beijing 100871 China

Cerium （III） tetraphenylporphyrin nitrate Ce（TPP）NO3 was synthesized by using meso- tetraphenylporphyrin （TPP） and Ce（NO3）.6H20 in mixture solution of CHC13 and C2HsOH （V：V=1：1）. The complex was characterized by UV-Vis, FT-IR, conventional fluorescence, MALDI-TOF-MS, and ^1H NMR spectral techniques. The structure of complex was proposed viaSpectral analyses, in which tetraphenylporphyrin was coordinated to a cerium ion in a tetradentate fashion, while one nitrate was coordinated to the same cerium ion. After bubbling NO to the solution of Ce（TPP）NO3 in CH2Cl2, spectral analyses suggested that Ce（TPP）NO3 could interact with NO to form a novel complex of Ce（TPP）（NO）NO3, and NO was coordinated to the center cerium ion. When nitrogen was poured into the Ce（TPP）（NO）（NO3） solution, the complex could be reduced to Ce（TPP）NO3.

关键词： Cerium (III) tetraphenylporphyrin nitrate NO Molecular recognition

Photochemical reaction between magnesium tetraphenyl porphyrin and oxygen

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Chinese Chemical Letters 2008年第10期19卷 1190-1192页

作者： Jian Bin Zhang Peng Yan Zhang Guo Hua Chen Fang Han xiong hui wei Department of Applied Chemistry College of Chemistry ＆ Molecular Engineering Peking University Beijing 100190 China College of Chemical Engine＇ering Inner Mongolia University of Technology Huhhot 010051 China

The photochemical reaction of magnesium tetraphenyl porphyrin （MgTPP） with O2 was studied in CH2Cl2 by steady-state fluorescence, UV-vis absorption, FTIR and MALDI-TOF MS measurements. These spectra indicate that O2 can react with MgTPP excited by irradiation, forming the stable 1：1 coordinated adduct of MgTPP-O2. In the adduct, the oxygen atoms of O2 may insert in the Mg-N bonds in MgTPP and bind with the nitrogen atoms of MgTPP to form N-O-Mg bonds.

关键词： Magnesium tetraphenyl porphyrin Photochemical reaction Linking oxygen

Supramolecular binding of amines with functional magnesium tetraphenylporphyrin for CO_2 capture

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Chinese Chemical Letters 2013年第3期24卷 249-252页

作者： Fei Gao Jian-Bin Zhang Chun-Ping Li Tian-Rui Huo xiong-hui wei College of Chemical Engineering Inner Mongolia University of Technology Department of Applied Chemistry College of Chemistry & Molecular EngineeringPeking University

In this work, magnesium tetraphenylporphyrin （MgTPP） was used as a new supramolecular amine-fixing agent. Once introduced, C02 easily competes with MgTPP for amines, leading to the release of MgTPP. The processes can be explained by the fact that the association constant （Kassoc） values of MgTPP with amines were in the range of 0.6 （ethanolamine） to 3.9 （ethylenediamine）, which are lower than the Kassoc values of C02 with these amines. MgTPP interacted with aniline, ethanolamine, pyrrolidine, or ethylenediamine to form 1：1 adducts. Ethylenediamine presents a stronger Kassoc value for MgTPP, so it was considered an optimal agent for C02 capture.

关键词： Supramolecular bindingFixationAmineMagnesium tetraphenylporphyrinC02 capture

Preparation of ultrafine Ti (C, N)-based cermet using oxygen-rich powders

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Journal of Central South University of Technology 2005年第z1期12卷 39-43页

作者： FENG Ping HE Yue-hui xiong wei-hao XIAO Yi-feng State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China State Key Laboratory of Die & Mould Technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China State Key Laboratory of Die & Mould Technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

The availability using oxygen-rich powders to prepare ultrafine Ti(C,N)-based cermets was investigated. The deoxidation process, denitrification phenomenon and the effect of deoxidation on microstructure and mechanical properties of sintered samples were discussed, respectively. The results show that oxygen in the samples prepared even with high oxygen contained in starting powders can be almost completely cleaned away through suitable sintering process. The ultrafine oxygen-rich powders have a significant effect on microstructure, which promotes the formation of white core phase. A ultrafine Ti(C,N)-based cermet with mean particle size of 0. 30 μm, uniform microstructure and excellent mechanical properties is successfully prepared. It is also found that there exists severe denitrification phenomenon in the preparation process of ultrafine Ti(C,N)-based cermet.

关键词： Ti(C,N)-based cermet ultrafine structured grain solid-state sintering deoxidation microstructure mechanical property

Chelerythrine chloride binding of guanosine in aqueous solution

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Chinese Chemical Letters 2009年第1期20卷 66-70页

作者： Fan Liu Jian Bin Zhang Zheng Fu Zhang Xiao Yan Zhang Zuo Peng Du xiong hui wei College of Chemical Engineering Inner Mongolia University of Technology Huhhot 010051 China Department of Applied Chemistry College of Chemistry & Molecular Engineering Peking University Beijing 100190 China

In this work, the interaction between chelerythrine （CHE） and guanosine is studied using UV-vis and fluorescence measurements at various temperatures. The UV-vis spectra show that the increasing guanosine concentrations result in the decreasing absorption intensity and red shift of CHE E absorption band （267 nm）. The fluorescence spectra are fitted to linear analysis, yielding a binding constant of 1.04×10^4 L/tool at 298.15 K of CHE with guanosine. Besides, with △rHm^θ = - 8.26 kJ/mol, △rGm^θ = -22.90 kJ/mol, and △rSm^θ = 49.38 J/（mol K） the interaction should be entropy-driven and exterothermic.

关键词： Chelerythrine (CHE) Guanosine UV-vis spectra Fluorescence spectra

Photochemical reaction of magnesium tetraphenyl porphyrin with sulfur dioxide

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Chinese Chemical Letters 2010年第7期21卷 787-789页

作者： Jian Bin Zhang Chun Ping Li Tian Rui Huo Zhan Ying Liu Li Hua Liu Tong Zhang Dong Yan Zhang xiong hui wei College of Chemical Engineering Inner Mongolia University of TechnologyHuhhot 010051China Department of Applied Chemistry College of Chemistry & Molecular EngineeringPeking UniversityBeijing 100871China

The photochemical reaction of magnesium tetraphenyl porphyrin（MgTPP） with sulfur dioxide（SO_2） was investigated in dichloromethane（CH_2Cl_2） by steady-state fluorescence,UV-vis absorption,MS,and XRD spectroscopic *** spectra showed that under irradiation MgTPP reacted with SO_2 to form 1：1 molecular adduct at first *** the process of keeping irradiation and maintaining the flow of SO_2,SO_2 was reduced into S^（2-） by MgTPP and the results were detected using MS and XRD *** the photochemical reaction of MgTPP with SO_2 is of key interest in elucidating fundamental photochemical reaction mechanisms associated with this class of chlorophyll in the presence of SO_2.

关键词： Photochemical reaction Sulfur dioxide Magnesium tetraphenyl porphyrin(MgTPP)

A Multi-objective Optimal Approach to Automated Construction of Sacrificial Multi-piece Molds

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Journal of Shanghai Jiaotong university(Science) 2008年第5期13卷 542-546页

作者：王会凤周雄辉陈巍 National Die and Mold CAD Engineering Research Center Shanghai Jiaotong University

Sacrificial multi-piece molds can be used for producing complex parts. To obtain the optimal design of molds automatically, a multi-objective optimal approach is proposed. Mold pieces number, material utilization and partitioning area are taken as the objective functions, and the machinability of each mold piece is taken as constraint condition. Genetic algorithm (GA) is adopted to realize global optimization of partitioning process. Each mold piece in optimal scheme can be manufactured by milling and drilling operations, which reduce the tooling cost and shorten product cycle obviously. Using the proposed approach, mold design can be significantly automated for making complex parts.

关键词： sacrificial multi-piece molds multi-objective optimization machinability genetic algorithm (GA)