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901.
YAO LinRan WANG Dong PENG Wen HU WeiWei YUAN HongMing & FENG ShouHua State key Laboratory of Inorganic Synthesis Preparative Chemistry College of Chemistry Jilin University Changchun China 《中国科学B辑(英文版)》2011,(6)
A series of pyrochlore oxides, R2Ru2O7 (R=Pr3+, Sm3+–Ho3+) were synthesized under mild hydrothermal conditions. All the samples crystallize in uniform octahedron characteristically. The products were characterized by powder X-ray diffraction, scanning electron microscopy, energy-disperse X-ray spectroscopy, and dc susceptibility, and the factors that affected the crystallization were discussed. It was found that the purity of products depends strongly on the raw materials and the amount of alkalinity in the... 相似文献
902.
LV YongJun XU Jian GUO Yong & SHAO ShiJun Key Laboratory of Chemistry of Northwestern Plant Resources Key Laboratory for Natural Medicine of Gansu Province Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou China State Key Laboratory for Oxo Synthesis Selective Oxidation China Graduate University of the Chinese Academy of Sciences Beijing China 《中国科学B辑(英文版)》2011,(5)
A boradiazaindacenes (BODIPY)-phenol conjugate,1,can act as a colorimetric and fluorometric sensor for sensitive and se-lective measurement of F-over AcO-and H2PO-4 in CH3CN. Sensor 1 gives response to F-in a 1:1 ratio via the deprotonation of the phenolic OH proton,which results in color change from pale yellow to light green and quenching of bright green fluo-rescence. 相似文献
903.
904.
DING Dan WANG Jing CHEN Ying WU Wei & JIANG XiQun Laboratory of Mesoscopic Chemistry 《中国科学B辑(英文版)》2011,(2)
In this work,gelatin-poly(acrylic acid) (GEL-PAA) nanospheres with diameter of around 35 nm were prepared using a polymermonomer (gelatin-AA) pair reaction system.These nanospheres can self-assemble into nanorods in aqueous solution at 4 °C.Based on the observation that the intermediate state of the formation of the nanorods and the facts that the self-assembly can only occur at relatively low temperature and the gelatin molecules on the outermost layer of the GEL-PAA nanospheres can be renatured to triple ... 相似文献
905.
WANG Lei LUO Yan-ling WEN Yong-hong LI Guang-hua FENG Shou-hua . Key Laboratory of Eco-chemical Engineering Ministry of Education College of Chemistry Molecular Engineering Qingdao University of Science Technology Qingdao P. R. China . State Key Laboratory of Inorganic Synthesis Preparative Chemistry College of Chemistry Jilin University Changchun 《高等学校化学研究》2011,(1)
With dimethylamine as a template, a new one-dimensional zincophosphite (C2H8N)·[Zn(HPO3)(H2PO3)] was prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction, FTIR spectrametry, elemental analysis, powder X-ray diffraction, and thermogravimetric analysis. The compound crystallized in the Monoclinic space group P2(1)/c, with cell parameters, a=0.78410(9) nm, b=1.54744(2) nm, c=0.81418(1) nm, β=105.8150(1)°, V=0.95049(2) nm3 and Z=4. The connectivity of the ZnO4 tetrahedron... 相似文献
906.
HUANG Chong ZHANG WenHan &LIU Bo Key Laboratory of Green Chemistry&Technology Ministry of Education College of Chemistry Sichuan University Chengdu China Key Laboratory of Synthetic Chemistry of Natural Substances 《中国科学B辑(英文版)》2011,(1)
An account of the total synthesis of(±)-,(+)-heliespirone A and(±)-,(-)-heliespirone C is presented.In the first-generation total synthesis,we found rac-24a could be easily transformed to rac-heliespirones A&C in a biomimic way.Taking the disappointing diastereoselectivity of prenylation from 3 to 4,the nonselective dihydroxylation from 4 to 5 and the lenthy route in strategy A into account,we designed a different synthetic plan targeting a highly enantioselective,concise and protective-group free synthesis... 相似文献
907.
LIN Feng ZHAO NanRong & LUO JiuLi Institute of Chemical Physics College of Chemistry Sichuan University Chengdu China 《中国科学B辑(英文版)》2011,(5)
A stochastic model of chemical reaction-heat conduction-diffusion for a one-dimensional gaseous system under Dirichlet or zero-fluxes boundary conditions is proposed in this paper. Based on this model,we extend the theory of the broadening exponent of critical fluctuations to cover the chemical reaction-heat conduction coupling systems as an asymptotic property of the corresponding Markovian master equation (ME),and establish a valid stochastic thermodynamics for such systems. As an illustration,the non-iso... 相似文献
908.
WU Nan-nan OUYANG Shun-li LI Zuo-wei LIU Jing-yao GAO Shu-qin .State Key Laboratory of Theoretical Computational Chemistry 《高等学校化学研究》2011,(4)
We analyzed the properties and structures of the hydrogen-bonded complexes of tetrahydrofuran(THF) and water by means of experimental Raman spectra and ab initio calculations.The optimized geometries and vibrational frequencies of the neat THF molecule and its hydrogen-bonded complexes with water(THF/H2O) were calculated at the MP2/6-311+G(d,p) level of theory.We found that the intermolecular hydrogen bonds which are formed from the binary mixtures of the neat THF and water with different molar ratios could... 相似文献
909.
LI HongBo LI Jing YANG ZhanJun XU Qin & HU XiaoYa College of Chemistry Engineering Yangzhou University Yangzhou China Chemistry Biology Engineering School Yancheng Institute of Technology Yancheng China 《中国科学B辑(英文版)》2011,(1)
A sub-picomole level topotecan hydrochloride determination method was first proposed using sodium dodecyl sulfate (SDS) as a sensitized reagent at a novel disposable electrode (an improved wax-impregnated graphite electrode).The effects of different kinds of surfactants on the electrochemical response to topotecan hydrochloride were examined.The results indicate the electrochemical signal was apparently improved by SDS.At optimal conditions,the oxidative peak current increased linearly with the logarithm of... 相似文献
910.
LI Hong-xin CHEN Xiao-tao XU Liang-zhong College of Chemistry Molecular Engineering Qingdao University of Science Technology Qingdao P. R. China 《高等学校化学研究》2011,(3):431-434
A series of novel neonicotinoids derivatives 4a―4p was designed and synthesized by introducing the ethylbenzene group into the thiazole ring, their structures were confirmed by IR, 1H NMR and elemental analysis. The crystal structure of compound 4j has been determined by X-ray diffraction analysis. 相似文献