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Synthesis and Characterization of a Novel pH-sensitive Complex for Drug Release

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Journal of wuhan university of Technology(materials {3.) 2010年第1期25卷 24-27页

作者：许东颖李光吉 Department of Polymer science and engineering South China University of Technology

A novel pH-sensitive complex was prepared by using oxidized konjac glucomannan and 4-aminosalicylic acid （4-ASA） through glutaraldehyde as a cross-linking agent. The product was characterized by FTIR and 13. NMR spectra, and the thermogravimetric analysis was also studied. The drug release studies in vitro showed that the amount of 4-ASA released from the complex was about 4%, 56% and 17% after 12 h at pH 1.2, 6.8 and 7.4, respectively. The data demonstrate that the rate of the drug release of the complex can be more effectively controlled by pH value. The results showed that the novel pH-sensitive complex could be potentially useful for colon-targeting drug delivery system.

关键词： konjac glucomannan pH-sensitivity drug release

Interface-directed sol-gel:direct fabrication of the covalently attached ultraflat inorganic oxide pattern on functionalized plastics

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science china Chemistry 2010年第1期53卷 173-182,287-288页

作者： GAN ShengHua,YANG Peng & YANG WanTai State Key Laboratory of chemical Resource engineering College of materials {3. and engineering,Beijing university of chemical Technology,Beijing 100029,china State Key Laboratory of chemical Resource engineering College of materials science and engineering Beijing University of Chemical Technology Beijing China

For plastic electronics and optics,the fabrication of smooth,transparent and stable crack-free inorganic oxide films(and patterning) on flexible polymeric substrates with strong bonding strength and controllable thickness from nanometers to micrometers is a key but still remains a *** versatile inorganic oxides,silica oxide film as SiOx is especially important because this semiconductor material could provide crucial properties in devices or serve as a base layer for further multilayer *** this paper,we describe a new interface-directed sol-gel method to fabricate flexible high quality silicon oxide film onto commodity *** resulting crack-free silica film has strong covalent bonding with polymer substrates,homogeneous morphology with ultralow roughness,highly optical transparency,tunable thickness from nm to μm,and easy patterning *** fabrication strategy relies on a novel photocatalytic oxidation reaction by photosensitive ammonium persulfate(APS),which is able to fabricate highly reactive hydroxyl monolayer surface on inert polymeric *** kind of hydroxylated surface could serve as nucleation and growth sites to initiate surface sol-gel *** a result,well-defined SiOx film deposition(gelation) occurs,and patterned hydroxylation regions could be easily utilized to induce the formation of patterned oxide film *** strategy also excludes the requirements of clean room and vacuum devices so as to fulfill low-cost and fast fabrication *** application examples from such high quality SiOx layer onto plastics are given but should not be limited within *** is that oxygen permeation rate of SiOx deposited polymer film decreases 25 times than pristine polymer substrate,which is good for the potential packaging *** other one is that silanization monolayer,for example,3.aminopropyltriethoxysilane(APTES),could be successfully constructed onto silica layer through classical silanization reac

关键词： surface patterning silicon oxide sol-gel polymer surface modification functional coatings

Preparation and Kinetics of the Thermal Decomposition of Nanosized CuC_2O_4-ZnC_2O_452H_2O

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wuhan university Journal of Natural sciences 2006年第3期11卷 667-671页

作者： CHEN Donghua HUANG Lianrong TANG Wanjun Hubei Key Laboratory for Catalysis and material science/College of chemical and Materal science South-Central University for Nationalities Wuhan 430074 Hubei China

The physical mixture of nanosized CuC2O4-ZnC2O4·2H2O, as precursors of CuO-ZnO, have been prepared by the one-step solid state reaction method at room temperature. The thermal decomposition processes taking place in the solid state oxalate mixture of nanometer CuC2O4-ZnC2O4·2H2O have been studied in static air using TG, DSC, XRD and TEM techniques. TEM showed that the grain size of the decomposition product is 5-15 nm. The values of the activation energy Eα were determined using the isoconversional procedure of KAS method and the Ozawa method. The most possible mechanism function f（α） of the thermal decompositions of nanosized CuC2O4-ZnC2O4·2H2O are defined using the comparative method, function models of tbe decomposition of CuC2O4 and ZnC2O4, follow tbe same mechanism function ＂Avrami-Erofeev equalion＂. The pre-exponential factor A is obtained on the basis of Eα and f（α）, thus the thermal analysis kinetic triplet of the decompositions of nanosized CuC2O4-ZnC2O4·2H2O are determined.

关键词： nanoparticle copper oxalate zinc oxalate kinetics characterization

Effect of Cooling Rate on Morphology and Oxygen Permeability of Polypropylene

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International Journal of Minerals,Metallurgy and materials 1999年第3期13卷 219-223页

作者： Wei Tian Raymond T. Whodhams(material science and engineering School, {3. of science and Technology Beijing, Beijing 100083. china)(Department of chemical engineering and Applied Chemistry {3. of Toronto, Toronto M5S IA4, Canada) material science and engineering School University of Science and Technology Beijing Beijing 100083 China Department of chemical engineering and Applied Chemistry University of Toronto Toronto Ont. M5S IA4 Canada

The influence of different cooling rates on the morphology and oxygen permeabilityr of polypropylene containing ferrocene has been investigated. The spherulitic crystalline size and structure, which can affect the oxygen permeability are dependent upon the heating temperature, annealing time and cooling rate. The modulus of the composite was measured b}' dynamic mechanical analysis.

关键词： polypropylene oxygen permeability cooling rate

Application of Flow Injection to the Analysis of Geochemical samples

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Application of Flow Injection to the Analysis of Geochemical...

Investigation on Vibrational Spectra and Structures of 4-Mercaptopyridine Monomer and Its Dihydrate

全国地球化学分析学术报告会与X射线光谱分析研讨会

作者： JIN Zexiang TANG Zhiyong (faculty of materials science and {3. engineering, china university of geosciences, wuhan 430074, P.R.china)

＜正＞ An integrated multi-functional device and a special functional valve for solution handling with flow injection are developed and they are applied to the analysis of geochemical samples in combination with the atomic spectrometry. The integrated multi-functional device is made up of polytetrafluoroethylene and it is a PTFE column of 100 mm in height and 80 mm in diameter,integrated with various functional components of flow injection analysis such as micro-column,gravity separator,displacement

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chemical Research in Chinese Universities 2006年第1期22卷 90-93页

作者： CHENG Jian-bo 1,2 , XUE Wei-qing 1 , ZHAO Bing 1** , ZHANG Gang 3.and GONG Bao-an 2 1. Key Laboratory for Supramolecular Structure and material of Ministry of Education, Jilin university, Changchun 13.012, P. R. china 2. {3. and engineering College of Chemistry and Biology, Yantai university, Yantai 264005, P. R. china 3. State Key Laboratory of Theoretical and Computational Chemistry, Jilin university, Changchun 13.023. P. R. china Key Laboratory for Supramolecular Structure and material of Ministry of Education Jiln University Changchun 130012 P. R. China science and engineering College of Chemistry and Biology Yantai University Yantai 264005 P. R. China State Key Laboratory of Theoretical and Computational Chemistry Jiln University Changchun 130023 P. R. China

The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory(DFT), viz. B3.YP method with the 6-3.1++G(d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the dihydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be consi- derably affected by the water molecules.

关键词： 4MPY Dihydrate Vibrational spectra DFT Molecular structure

Oxygen Permeability of Polypropylene Containing Polyisobutene with Magnesium Acetate

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International Journal of Minerals,Metallurgy and materials 2000年第2期14卷 118-121页

作者： Wei Tian Raymond T. Woodhams(material science and engineering School, {3. of science and Technology Beijing, Beijing 100083. china)(Dept. of chemical engineering and Applied Chemistry, {3. of Toronto, Torono M5S IA4, Canada) material science and engineering School University of Science and Technology Beijing Beijing 100083 China Dept. of chemical engineering and Applied Chemistry University of Toronto Toronto Ont. M5S IA4 Canada

The oxygen permeabilities of polypropylene films are reduced by adding a minor percentage of a polyisobutene ionomer. The polyisobutene ionomers were prepared by in situ salt exchange of magnesium acetate with maleated polyisobutenes of commercially available low relative molecular mass. The more polar magnesiurn salts aided phase separaion during crystallization from the molten polypropylene mixtusre. Scanning electron microscope photographs revealed that the polyisobotene ionomer is largely concentratd in the amorphous regions between the polypropylene spherulites, where the ionomer tends to concentrate during crystallization. The influence of the polyisobutene ionomer on the oxygen permeability of polypropylene was found to be slightly dependent upon the relative molecular mass of the polyisobutene precursor. Under optimum conditions, the oxygen permeability of polypropylene is reduced by 20%with only 1% additive.

关键词： oxygen permeability polypropylene polyisobutene

chemical Extraction Preparation of Delithiated Cathode materials of Li-ion Battery

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Journal of wuhan university of Technology(materials {3.) 2009年第6期24卷 863-866页

作者：闫时建 School of materials science and engineering Taiyuan University of Science and Technology

A method of conventional chemical reaction to prepare delithiated cathode materials of Li-ion battery was introduced. The cathode material of Li-ion battery was mixed with oxidizing agent Na2S2O8 in water solution, and the solution was stirred continuously to make the chemical reaction proceed sufficiently, then the reaction product was filtered and finally the insoluble delithiated cathode material was obtained. A series of tests were conducted to verify the composition, crystal structure and electrochemical property of the delithiated cathode materials were all desirable. This method overcomes the shortcomings of battery charging preparation and chemical extraction preparation employing other oxidizing agents.

关键词： chemical extraction delithiated cathode material Li-ion battery

Online diagnosis of electron excitation temperature in CH_4+H_2 discharge plasma at atmospheric pressure by optical emission spectra

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science china(Physics,Mechanics & Astronomy) 2008年第12期51卷 1892-1896页

作者： CUI JinHua1, XU ZhenFeng2, ZHANG JiaLiang3., NIE QiuYue3. XU GenHui4 & REN LongLiang5 1 faculty of Chemistry and chemical engineering, Liaoning Normal {3., Dalian 116021, china 2 Technique Center for Modern Education, Liaodong College, Dandong 126709, china 3.State Key Laboratory for materials Modification by Laser, Ion and Electron Beams, Dalian {3. of Technology, Dalian 116023. china 4 College of chemical engineering, Tianjin {3., Tianjin 3.0072, china 5 Department of Physics, {13. College, Tianjin {3., Tianjin 3.0072, china faculty of Chemistry and chemical engineering Liaoning Normal University Dalian China Technique Center for Modern Education Liaodong College Dandong China State Key Laboratory for materials Modification by Laser Ion and Electron Beams Dalian University of Technology Dalian China College of chemical engineering Tianjin University Tianjin China Department of Physics Science College Tianjin University Tianjin China

Methane coupling under low temperature plasmas at atmospheric pressure is a green process by use of renewable sources of energy. In this study, CH4+H2 dis- charge plasma was on-line diagnosed by optical emission spectra so as to char- acterize the discharge system and to do spade work for the optimization of the technical parameters for future commercial production of methane coupling under plasmas. The study was focused on a calculation method for the online diagnosis of the electron excitation temperature in CH4+H2 discharge plasma at atmospheric pressure. The diagnostic method is easy, efficient and fairly precise. A serious er- ror in a literature was corrected during the reasoning of its series of equations formerly used to calculate electron temperatures in plasmas.

关键词： low temperature plasma electron excitation temperature optical emission spectrum online diagnosis