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Chinese Journal of Chemistry 2006年第2期24卷 219-223页

作者：任莹辉宋纪蓉黄洁马海霞王花丽胡怀明文振翼 Shaanxi Key Laboratory of Physico-inorganic Chemistry Department of Chemical Engineering Northwest University Xi'an Shaanxi 710069 China Department of Chemistry Northwest University Xi'an Shaanxi 710069 China Modern Physics Institute Northwest University Xi'an Shaanxi 710069 China

4-（4,6-Dimethylpyrimidin-2-yl）-3-thio-allophanic acid methyl ester was synthesized with mixing 2-amino-4,6- dimethylpyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray diffraction measurement were obtained by recrystallization from dimethylformamide at room temperature. The crystal belongs to monoclinic symmetry with space group C2/m, and crystal parameters of a= 1.7537（5） nm, b= 0.6759（2） nm, c=1.1148（3） nm, β=118.557（4）°, V=1.1605（6） nm^3, Z=4, De= 1.375 g/cm^3,μ=0.271 mm^-1, F（000）=504, and 1519 [1〉2σ（I）] observable independent reflections were used for the determination and refmement of the crystal structures with final R1 of 0.0372 and wR2 of 0.0992. The theoretical investigation of the title compound was carried out with DRT-B3LYP/6-311G, HF/6-311G and MP2/6-311G methods, and the atomic net charges and the population were discussed.

关键词： 2-amino-4,6-dimethylpyrimidine thiourea preparation crystal structure theoretical calculation

preparation and Crystal Structure of 3-(2-Hydroxyphenyl)-6-(4-nitrophenyl)-7H- 1,2,4-triazolo[3,4-b][1,3,4 ]thiadiazine

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Chemical Research in Chinese Universities 2005年第1期21卷 69-72页

作者： ZOUKai-huang ZHANGLi-xue ZHANGAn-jiang LEIXin-xiang HUANGHui-hua ZHANGZi-yi SchoolofChemistryandMaterialsScience WenzhouNormalCollegeWenzhou325027P.R.China／／DepartmentofBiologyandChemistryFujianEducationalCollegeFuzhou350001P.R.China SchoolofChemistryandMaterialsScience WenzhouNormalCollegeWenzhou325027P.R.China CollegeofChemistryandChemicalEngineering LanzhouUniversityLanzhou730000P.R.China

3-(2-Hydroxyphenyl)-6-(4-nitrophenyl)-7H-1,2,4-triazolo[3,4-b][1,3,4] thiadiazine, C 16H 11N 5O 3S, was prepared by the cyclization of 3-(2-hydroxyphenyl)-4-amino-5-mercapto-1,2,4-triazole with 2-bromo-4-nitroacetophenone. The compound was characterized by means of elemental analysis, IR, 1H NMR, 13C NMR, mass spectrometry, and X-ray diffraction. The compound crystallizes in a monoclinic system with space group C c, a=2.1853(4) nm, b=2.1192(5) nm, c=1.3526(3) nm, β=95.21(2)°, V=6.238(2) nm3 , D calcd.=1.505 Mg/m3, Z=16, F(000)=2916, R 1=0.0501, wR 2=0.0427. A comparison between the crystal structures of 1,2,4-triazolo[3,4-b] [1,3,4] thiadiazine and 1,2,4-triazolo[3,4-b][1,3,4] thiadiazole was made in the structural view. A two-dimensional network is formed by hydrogen bonds and π-π stacking interactions.

关键词： Triazolothiadiazine preparation Spectral characterization Crystal structure π-π stacking interaction

preparation of Nd_2O_3 nanorods in SDBS micelle system

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Journal of Rare Earths 2014年第11期32卷 1027-1031页

作者：吴萍萍张之魁宋根萍 School of Chemistry and Chemical Engineering Yangzhou University Far East International Plaza

Well-crystallized Nd2O3 nanorods were prepared in the aqueous solution containing neodymium nitrate, sodium hydroxide（dissolved in ethanol） and sodium dodecyl benzene sulfonate（SDBS）. One dimensional nanorods of neodymium hydroxide were synthesized first, which was then placed at different temperatures（600 and 800 ℃） in a calcar for 10 h to form Nd2O3 nanorods. The morphology and crystal structure of the products were investigated by X-ray diffraction, transmission electron microscopy, field emission transmission electron microscopy, Fourier transform infrared spectroscopy and fluorescence spectrometry. By using SDBS micelles as a template, this method manufactured uniform morphology of hexagonal one-dimensional neodymium oxide nanorods with a diameter ranging from 20 to 70 nm. The length of the nanorods increased with prolonged reaction time.

关键词： Nd2O3 nanorods preparation rare earth elements SDBS micelle

preparation AND MECHANICAL PROPERTIES OF T-ZnOw/PS COMPOSITES

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Chinese Journal of Polymer Science 2009年第2期27卷 173-181页

作者：王勇 Key Laboratory of Advanced Technologies of Materials (Ministry of Education) School of Materials Science and EngineeringSouthwest Jiaotong University State Key Laboratory of Polymer Materials Engineering (Sichuan University)

The main subject of this work is about the preparation of T-ZnOw/PS composites through different methods and the evaluation of mechanical properties of the composites.Different surface modification methods of T-ZnOw whiskers,the so called wet-type modification and dry-type modification,and different molding processing methods of T-ZnOw/PS composites,namely compression molding and injection molding,have been employed.Two different coupling agents, titanate coupling agent (NDZ105) and silane coupling agent (KH560),have been used to treat T-ZnOw.Both the interface structure between T-ZnOw whiskers and PS and the distribution of integrated T-ZnOw whiskers in composites have been studied by SEM.The mechanical properties of T-ZnOw/PS composites obtained through the above different methods have been studied comparatively.Although the tensile strength of the composites decreases slightly,the impact strength and tensile modulus increase with increasing the content of T-ZnOw in the composites.Both coupling agents and molding methods have great influence on the mechanical properties of the composites.The study of the impact-fractured surface shows that craze formation in PS matrix during the impact process is the main reason for the improvement of the composite toughness.

关键词： T-ZnOw/PS preparation Mechanical properties.

preparation of Anhydrous LnCl_3(Ln=Eu, Er, Lu) by Chemical Vapor Transport

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Journal of Rare Earths 2000年第2期18卷 152-154页

作者： WANG Lin shan, LI Ying, WANG Yu hong (Department of Chemistry, Northeastern University, Shenyang 110006, China) Department of Chemistry Northeastern University Shenyang 110006 China

Anhydrous lanthanide chlorides LnCl 3(Ln=Eu, Er, Lu) which are not easy to prepare in other ways were prepared by chemical vapor transport(CVT) method. Ln 2O 3 reacted with an excess of Al 2Cl 6 at 300 ℃ to produce LnCl 3. LnCl 3 reacted with Al 2Cl 6 at high temperature to form the gaseous complexes which decomposed at low temperature. LnCl 3 was then separated from other solids by controlling a proper temperature gradient. Residual Al 2Cl 6(g) was removed by the carrier of dry Cl 2 N 2 gases at 200 ℃. The yield rates are >90%, and the purity of products is >99 5%. The high purity of anhydrous lanthanide chlorides can be obtained by CVT method.

关键词： rare earths preparation chemical vapor transport

preparation,Characterization,and Catalytical Application of MgCoAl-Hydrotalcite-Like Compounds

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Journal of Natural Gas Chemistry 2007年第4期16卷 371-376页

作者： Kai Yan Xianmei Xie Jinping Li Xiulan Wang Zhizhong Wang College of Chemistry and Chemical Engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China

MgCoAl-hydrotalcite-like compounds （MgCoAI-HTLcs） were synthesized using the coprecipitation method of variable pH values. The effect of each factor on the preparation of HTLcs was discussed systematically, which included pH values, mole ratios of Mg2＋ to Co2＋, the concentrations of the solution, and the temperature and time of the hydrothermal treatment. Besides, the thermal decomposition of MgCoAI-HTLcs was discussed. X-ray diffraction, thermogravimetric analysis, and FT-IR spectroscopy were performed to characterize the MgCoAI-HTLcs samples. The results showed that when the pH = 7.6-8.5 or 5.5-6.2, atomic ratios of （Mg^2＋＋Co2＋）/Al^3＋ 2 and Mg^2＋/Co^2＋ ranging from 1.00 to 2.00, temperature and time of hydrothermal treatment being 110℃ and 6 h, unique MgCoAI-HTLcs with high crystallinity could be obtained. When the calcination temperature was up to 250℃, the MgO phase was detected coexisting with Al2O3 and MgAl2O4 was highly spreaded on the derived mixed oxides. The synthesis reaction of benzoin methyl ether with methanol and benzaldehyde was chosen to study the catalytic activity of MgCoAI-HTLcs. The catalyst showed high activity and high stability in the synthesis of benzoin methyl ether in the feasible condition.

关键词： MgCoAl-hydrotalcite-like compounds preparation benzoin methyl ether methanol benzaldehyde

preparation and Antioxidative Effects of Soybean Peptides

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Chemical Research in Chinese Universities 1999年第2期15卷 48-53页

作者： MENG Xianju ZHANG Xuezhong WANG Huaiyu Laboratory of Enzyme Engineering Jilin UniversityChangchun130012 College of Food Engineering Jilin Agriculture UniversityChangchun130118

ＩｎｔｒｏｄｕｃｔｉｏｎＦｒｅｅｒａｄｉｃａｌｓｐｒｏｄｕｃｅｄｂｙｌｉｐｉｄｐｅｒｏｘｉｄａｔｉｏｎｃａｎｃａｕｓｅｃｅｌｄａｍａｇｅａｎｄａｖａｒｉｅｔｙｏｆｄｉｓｅａｓｅｓ．Ｉｔｈａｓｂｅｅｎｒｅｐｏｒｔｅｄｔ... 详细信息

ＩｎｔｒｏｄｕｃｔｉｏｎＦｒｅｅｒａｄｉｃａｌｓｐｒｏｄｕｃｅｄｂｙｌｉｐｉｄｐｅｒｏｘｉｄａｔｉｏｎｃａｎｃａｕｓｅｃｅｌｄａｍａｇｅａｎｄａｖａｒｉｅｔｙｏｆｄｉｓｅａｓｅｓ．Ｉｔｈａｓｂｅｅｎｒｅｐｏｒｔｅｄｔｈａｔｓｏｍｅｎｏｎ－ｅｎｚｙｍａ...

关键词： Soybean peptides preparation Antioxidative effect

preparation and photoelectrochemical performance of TiO_2/Ag_2Se interface composite film

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Science China Chemistry 2009年第12期52卷 2213-2218页

作者： ZHAO JuanJuan,JIANG BangTong,ZHANG ShengYi,NIU HeLin,JIN BaoKang & TIAN YuPeng Department of Chemistry,Anhui University,Hefei 230039,China Department of Chemistry Anhui University Hefei China

Coupling TiO2 with a narrow band gap semiconductor acting as the photosensitizer has attracted much attention in solar energy exploitation. In this work,the porous TiO2 film was first formed on the conducting glass plate (CGP) substrate by the decomposition of polyethylene glycol (PEG) mixing in titanium hydroxide sol at 450℃. Then,the TiO2/Ag2Se interface composite film was fabricated by interface reaction of AgNO3 with NaSeSO3 on the activated surface of porous TiO2 film. The results of SEM and XRD analyses indicated that the porous TiO2 layer was made up of the anatase crystal,and the Ag2Se layer was made up of congregative small particles that have low-temperature α-phase structure. Due to its efficient charge separation for the photo-induced electron-hole pairs,the TiO2/Ag2Se interface composite film as-prepared has good photovoltaic property and high photocurrent response for visible light,which have been confirmed by the photoelectrochemical measurements.

关键词： TiO2/Ag2Se interface composite film preparation measurement photoelectrochemistry

Advancements in the preparation of high-performance liquid chromatographic organic polymer monoliths for the separation of small-molecule drugs

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Journal of Pharmaceutical Analysis 2018年第2期8卷 75-85页

作者： Xiali Ding Jing Yang Yuming Dong Institute of Pharmaceutical Analysis School of PharmacyLanzhou UniversityLanzhouGansu 730000PR China Lanzhou Universty-Techcomp(China)Ltd.Joint Laboratory of Pharmaceutical Analysis LanzhouGansu 730000PR China

The various advantages of organic polymer monoliths, including relatively simple preparation processes,abundant monomer availability, and a wide application range of pH, have attracted the attention of chromatographers. Organic polymer monoliths prepared by traditional methods only have macropores and mesopores, and micropores of less than 50 nm are not commonly available. These typical monoliths are suitable for the separation of biological macromolecules such as proteins and nucleic acids, but their ability to separate small molecular compounds is poor. In recent years, researchers have successfully modified polymer monoliths to achieve uniform compact pore structures. In particular, microporous materials with pores of 50 nm or less that can provide a large enough surface area are the key to the separation of small molecules. In this review, preparation methods of polymer monoliths for high-performance liquid chromatography, including ultra-high cross-linking technology, post-surface modification, and the addition of nanomaterials, are discussed. Modified monolithic columns have been used successfully to separate small molecules with obvious improvements in column efficiency.

关键词： High-performance liquid chromatography Polymer monolith preparation methods Small molecules

preparation and evaluation of tamsulosin hydrochloride sustained-release pellets modified by two-layered membrane techniques

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Asian Journal of Pharmaceutical Sciences 2015年第1期10卷 31-39页

作者： Jingmin Wang Yinghua Sun Bo Li Rui Fan Bing Li Tengrui Yin Ling Rong Jin Sun Shenyang Pharmaceutical University No.103Wenhua RoadShenyang 110016China

The aim of the present study was to develop tamsulosin hydrochloride sustained-release pellets using two-layered membrane techniques.Centrifugal granulator and fluidizedbed coater were employed to prepare drug-loaded pellets and to employ two-layered membrane coating respectively.The prepared pellets were evaluated for physicochemical characterization,subjected to differential scanning calorimetry(DSC)and in vitro release of different pH.Different release models and scanning electron microscopy(SEM)were utilized to analyze the release mechanism of Harnual■ and home-made pellets.By comparing the dissolution profiles,the ratio and coating weight gain of Eudragit■ NE30D and Eudragit■ L30D55 which constitute the inside membrane were identified as 18:1 and 10%-11%.The coating amount of outside membrane containing Eudragit■ L30D55 was determined to be 0.8%.The similarity factors(f_(2))of home-made capsule and commercially available product(Harnual■)were above 50 in different dissolution media.DSC studies confirmed that drug and excipients had good compatibility and SEM photographs showed the similarities and differences of coating surface between Harnual■ and self-made pellets before and after dissolution.According to Ritger-Peppas model,the two dosage form had different release mechanism.

关键词： preparation In vitro evaluation Tamsulosin hydrochloride Sustained-release pellets Drug release mechanism Stability study