检索结果-南通市图书馆

维普期刊数据库

A controllable soft-templating approach to synthesize mesoporous carbon microspheres derived from d-xylose via hydrothermal method

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2020年第3期38卷 183-188页

作者： Jian Su Changqing Fang Mannan Yang Youliang Cheng Zhen Wang Zhigang Huang Caiyin You School of Materials Science and Engineering Xi’an University of TechnologyXi’an710048China Faculty of Printing Packaging Engineering and Digital Media TechnologyXi’an University of TechnologyXi’an710048China School of Mechanical and Precision Instrument Engineering Xi’an University of TechnologyXi’an710048China Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics Beijing Technology and Business UniversityBeijing100048China

Highly dispersed carbon microspheres(CMSs)derived from d-xylose were successfully synthesized under hydrothermal conditions and followed by further carbonization,in which F127 was used as a soft ***-synthesized products were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),flourier transform infrared spectroscopy(FT-IR),thermal gravimetric(TG)and X-ray diffraction(XRd).The results showed that the morphology and structure of the CMSs prominently depended on the stirring speed during hydrothermal *** resultant CMSs principally had non-porous structure without stirring and had a very smooth *** the stirring speed increased to 200 rpm,the synthesized mesoporous carbon microspheres at 220?C for 24 h(CMSs-5)had a uniform size distribution of 1–1.4μm and a specific surface area of 452 m^2/***,with further increasing to 400 rpm,as-fabricated carbon products were mostly amorphous with a low degree of *** demonstrated that the diameter of the products decreased with the increase of stirring ***,the sphericity product yield of CMSs reduced with the increase of stirring *** result showed that all the obtained samples contained partial graphite *** addition,a formation mechanism was proposed that involved polymerization product as the precursors for microsphere *** controllable and green strategy may provide a great convenience to study properties and applications of carbon microspheres.

关键词： d-xylose Mesoporous carbon microsphere Soft template Hydrothermal method Stirring

维普期刊数据库

Synthesis of New Thiazine and Thiosemicarbazone derivatives from d-xylose

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第12期17卷 1563-1565页

作者： Xiao Ming JI He Ping SUN Hai Wei XU Hong Min LIU New drug Research ＆ development Center Zhenzhou University Zhengzhou 450052

1,2-O-Isopropylidene-5-O-p-toluenesulfonyl-α-d-erythro-pentofuranos-3-ulose 1 was treated with thiourea and aminothiourea to give a d-ribose derivative 2 bearing a 2-amino 1,3-thiazine ring and a thiosemicarbazone derivative 5, respectively. 2 was acylated with Ac20 and propandioic acid to afford two acylation derivatives 3 and 4, respectively. Reduction of 5 with NaBH4 in methanol produced a hydrothiosemicarbazone derivative 6. The absolute configuration of 2 was confirmed by X-ray crystallographic analysis. The structures of all products were elucidated by IR, NMR and HRMS spectra.

关键词： Thiourea aminothiourea thiazine d-xylose synthesis.

维普期刊数据库

脾虚证小鼠血清d-xylose及GAS含量的分析

在线全文

学校读者我要写书评

暂无评论

世界最新医学信息文摘 2017年第83期 10-11页

作者：贺志有侯养彪杨涛李雪芳李浩渭南职业技术学院

目的分析小鼠脾虚证建模前后血清d-xylose及GAS含量的变化。方法通过利血平法建立小鼠的脾虚证动物模型。ELISA法及比色分析法分别测定各组小鼠血清GAS及d-xylose的含量。结果模型组与正常组比较,模型组血清GAS及d-xylose含量显著降低... 详细信息

目的分析小鼠脾虚证建模前后血清d-xylose及GAS含量的变化。方法通过利血平法建立小鼠的脾虚证动物模型。ELISA法及比色分析法分别测定各组小鼠血清GAS及d-xylose的含量。结果模型组与正常组比较,模型组血清GAS及d-xylose含量显著降低。结论脾虚模型证小鼠造模前后血清GAS及d-xylose含量有明显改变,并为该证型提供实验数据。

关键词：血清 GAS d-xylose 脾虚证

Effect of external electric field upon charge distribution, energy and dipole moment of selected monosaccharide molecules

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Natural Science 2012年第5期4卷 276-285页

作者： Jozef Mazurkiewicz Piotr Tomasik Cracow College of the Health Promotion Cracow Poland department of Chemistry and Physics University of Agriculture Cracow Poland

External electric field of 0.001, 0.01 and 0.05 a.u. changes distribution of the electron density in α- and β-d-glucose, α- and β-d-galactose, α- and β-fructopyranoses and α- and β-fructofuranoses, α- and β-d-ribofuranoses and α and β-d-xylo- furanoses. Hyper-Chem 8.0 software was used together with the AM1 method for optimization of the conformation of the molecules of monosaccharides under study. Then polarizability, charge distribution, potential and dipole moment for molecules placed in the external electric field of 0.000, 0.001, 0.01 and 0.05 a.u. were calculated involving dFT 3-21G method. Application of the external field induced polarizability of electrons, atoms and dipoles, the latter resulting in eventual reorientation of the molecules along the applied field of the molecules and the electron density redistribution at particular atoms. Increase in the field strength generated mostly irregular changes of the electron densities at particular atoms of the molecules as well as polarizabilities. Energy of these molecules and their dipole moments also varied with the strength of the field applied. Results of computations imply that saccharides present in the living organisms may participate in the response of the living organisms to the external electric field affecting metabolism of the molecules in the body fluids by fitting molecules to the enzymes. Structural changes of saccharide components of the membranes can influence the membrane permeability.

关键词： d-Fructose dipole Moments d-Galactose d-Glucose Polarizabilty d-Ribose d-xylose