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Science china chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2 & TANG XinLiang1,3 1 Technical Institute of Physics and chemistry,chinese academy of sciences,beijing 100080,china 2 college of chemistry and chemical engineering,graduate university of chinese academy of sciences,beijing 100049,china 3 School of chemical engineering and Environment,beijing Institute of Technology,beijing 100081,china Technical Institute of Physics and chemistry Chinese Academy of Sciences Beijing China college of chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing China School of chemical engineering and Environment Beijing Institute of Technology Beijing China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2-hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Thermal expansion properties and hygro-scopicity of Y_(2-x)Sm_xW_3O_(12) (x=0.0-0.4) compounds

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Science china(Technological sciences) 2008年第1期51卷 25-32页

作者： YU ZhouXiang1, PENG Jie2, WANG Hui2, WU MeiMei2, CHENG YingZhi2, HU ZhongBo2 & CHEN DongFeng1 1 china Institute of Atomic Energy, P.O. Box 275 (30), beijing 102413, china 2 college of chemistry and chemical engineering, graduate university of chinese academy of sciences, beijing 100049, china china Institute of Atomic Energy Beijing China college of chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing China

A novel class of solid solutions of Y2-xSmxW3O12 (x = 0.0–0.4) were synthesized and studied by means of powder X-ray diffraction. All samples crystallize in an ortho- rhombic space group Pnca. The lattice parameters a, b and c of Y2-xSmxW3O12 in- crease with increasing Sm content. Since the compounds of this series hydrate at room temperature, thermogravimetric (TG) analysis was carried out. The result shows that the compound stores less water with increasing Sm content. The thermal expansion properties of Y2-xSmxW3O12 (x = 0.1, 0.3 and 0.4) were investi- gated with high temperature X-ray diffraction. Negative thermal expansion coeffi- cient αl becomes less negative from -6.644×10-6 to -6.211×10-6℃-1 when x changes from 0.1 to 0.4.

关键词： rare earth tungstates negative thermal expansion hygroscopic XRD

Highly sensitive and selective chemosensor for Cu～(2+) detection based on a N-propargyl rhodamine 6G-hydrazide derivative

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Science china chemistry 2012年第4期55卷 626-631页

作者： MA Xing1,2,LIU Jun1,DU YuGuo1,2,WEI GuoHua1 & WEI DongBin1 1State Key Laboratory of Environmental chemistry and Ecotoxicology Research Center for Eco-Environmental sciences,chinese academy of sciences,beijing 100085,china 2college of chemistry and chemical engineering,graduate university of chinese academy of sciences,beijing 100049,china State Key Laboratory of Environmental chemistry and Ecotoxicology Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing China college of chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing China

A novel fluorescence ＂turnon＂ probe for CH^2＋ detection has been designed based on a Cu^2＋ triggered spirolactam ringopening reaction. The synthetic probe is a doubleresponsive fluorescent and colorimetric Cu^2＋specific sensor. In aqueous solution, it exhibits high selectivity and excellent sensitivity. With a significant color change visible to the naked eye at the concentration of 3 *** （ca. 0.19 mg/L）, about one magnitude lower than the WHO （World Health Organization） recommended level （2.0 mg/L） for Cu^2＋ions in drinking water, the probe could be used to monitor Cu^2＋ ions in drinking water.

关键词： copper – fluorescent chemosensor – chromogenic probe – rhodamine

A Facile Method to Prepared Poly（vinylidene fluoride） Thin Films with High Content of Beta-phase

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A Facile Method to Prepared Poly（vinylidene fluoride） Thin...

Effects of combined substitution of Dy and Mo or Si on the crystal structures and magnetic properties of Nd_(1-y)Dy_yFe_(11-x)TiM_x(M=Mo,Si) compounds

氟化学与美好生活——中国化学会第十一届全国氟化学会议

作者： Rui Song~1,Linghao He~1,Lu Yao~1,Jie Yang~2,Jing Sun~1,Chuandao Wang~1,Wei Huang~3 1.Key Lab of Surface and Interface sciences of Henan Provincial,Zhengzhou university of Light Industry,Zhengzhou,450005,china 2.college of chemistry and chemical engineering,graduate university of chinese academy of sciences,beijing,100049,china 3.Laboratory of Advanced Polymer Materials,Institute of chemistry,chinese academy of sciences,beijing,100080,china

＜正＞Poly（vinylidene fluoride）（PVDF）has attracted much attention due to its chemical resistance,abrasion resistance,radiation resistance,mechanical strength and piezoelectric properties,and has been widely used in diverse *** most important applications for PVDF is in piezoelectric,pyroelectric and ferroelectric fields due to theβ-phase,which has an all-trans conformation（TTTT）and is the strongest polar phase among all other ***

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来源： cnki会议评论

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Science china chemistry 2009年第8期52卷 1097-1103页

作者： LI XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin college of chemistry and chemical engineering,graduate university of chinese academy of sciences,beijing 100049,china college of chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12-type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

Meet Our New Editorial Board Members of Spotlights

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chinese Journal of chemistry 2024年第16期42卷 1932-1936页

作者： Editorial Office of chinese Journal of chemistry 不详

Editorial Board Member of *** ***,college of Materials Science and engineering beijing university of chemical ***:2006-2010,B.S.,Materials Science and engineering,beijing university of chemical Technology.2010-2015,Ph... 详细信息

关键词： Spotlight Editorial Board

Changes of decay rates of radioactive ^(111)In and ^(32)P induced by mechanic motion

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Science china chemistry 2007年第2期50卷 170-174页

作者： HE YuJian1,QI Fei2 & QI ShengChu3 1 college of chemistry and chemical engineering,graduate university of chinese academy of sciences,beijing 100049,china 2 No. 1,Gravenhurst Court,Gaithersburg,Md 20878,USA 3 Department of Applied chemistry,Peking university,beijing 100871,china college of chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing China No. 1 Gravenhurst Court Gaithersburg USA Department of Applied chemistry Peking University Beijing China

The changes of decay rates of radionuclide 111In(electron capture) and 32P(β decay) induced by exter-nal mechanic motion are studied. The results indicate that,in the external circular rotation in clockwise and anticlockwise centrifuge on Northern Hemisphere(radius 8 cm,2000 r/min) ,the half life of 111In compared with the referred(2.83 d) is decreased at 2.83% and increased at 1.77%,respectively;the half life of 32P compared with the referred(14.29 d) is decreased at 3.78% and increased at 1.75%,respec-tively. When the clockwise and anticlockwise rotations increase to 4000 r/min,the half life of 111In is decreased at 11.31% and increased at 6.36%,respectively;the half life of 32P is decreased at 10.08% and increased at 4.34%,respectively. When the circular rotation is removed,the decay rates of 111In and 32P return back to the referred,respectively. It is found that the external circular rotations in clockwise and anticlockwise centrifuge selectively increased and decreased the decay rates of 111In and 32P,respec-tively,and the effects are strongly dependent on the strength of circular rotation. It is suggested that these effects may be caused by the chiral interaction.

关键词： circular rotation helical motion 111In 32P decay rate chirality

Size-dependent hydroxyl radicals generation induced by SiO_2 ultra-fine particles: The role of surface iron

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Science china chemistry 2009年第7期52卷 1033-1041页

作者： SHANG Yu1, ZHU Tong1, LI Yi1,2 & ZHAO JinCai3 1 college of Environmental sciences and engineering, Peking university, beijing 100871, china 2 chinese academy of Meteorological sciences, beijing 100871, china 3 Institute of chemistry, chinese academy of sciences, beijing 100871, china college of Environmental sciences and engineering Peking University Beijing China chinese academy of Meteorological sciences Beijing China Institute of chemistry Chinese Academy of Sciences Beijing China

Oxidative stress and hydroxyl radicals (·OH) play important roles in adverse health effects caused by inhalable ambient air particles (PM10). The ultra-fine fraction of PM10 has been hypothesized as one of the critical contributors to ·OH generation. Both in vivo and in vitro studies have shown that ultra-fine particles (UFPs) or nano-particles generate more ·OH than larger particles with identical mass and composition. Both the surface area and surface-adsorbed redox-active metals have been suggested as factors to determine the oxidative capacity of UFPs. In this study, the ·OH-generating capability of dif-ferent sizes of SiO2 particles was investigated in order to determine which factor influences particle-induced ·OH generation. The amount of ·OH generated in both acellular and cellular systems was quantified using a capillary electrophoresis method following exposure to SiO2 particles with diameters of 14, 100, and 500 nm. The amount of ·OH was strongly dependent on particle size, and a significant enhancement was observed only with 14 nm particles. Further studies indicated a close association between ·OH and iron ion concentration (R2 = 0.812, p2 particles is presented as a possible mechanism of UPFs-induced ·OH generation. The SiO2 acted as an inert substrate, and the surface of ultra-fine SiO2 particles acted as a carrier for iron.

关键词： ultra-fine particles nano-particles ·OH oxidative stress size-effect

SiO/CNTs:A new anode composition for lithium-ion battery

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Science china chemistry 2009年第12期52卷 2047-2050页

作者： REN YuRong1,2,3?,QU MeiZhen1 & YU ZuoLong1 1 Chengdu Institute of Organic chemistry,chinese academy of sciences,Chengdu 610041,china 2 college of chemistry,Jilin Normal university,Siping 136000,china 3 graduate university of chinese academy of sciences,beijing 100039,china Chengdu Institute of Organic chemistry Chinese Academy of Sciences Chengdu China college of chemistry Jilin Normal University Siping China graduate university of chinese academy of sciences Beijing China

A new anode composition SiO/CNTs (carbon nanotubes) has been prepared by chemical vapor deposition (CVD) method. The results of scanning electron microscopy (SEM) confirm that CNTs deposit on small SiO particles,form a cage,and enwrap SiO particles tightly. SiO/CNTs anode composition exhibits an initial discharge and charge capacity of 1171 and 789 mAh/g,and maintains a reversible capacity of 500 mAh/g after 80 cycles. The improvement of the cyclic performance for SiO/CNTs composition is related to the maintaining of the electric network during cycling,which benefits from a tight contact between CNTs and SiO particles.

关键词： SiO/CNTs CVD composition anode Li-ion battery

Phase relationship of complex multi-component system in chromate cleaner production

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Progress in Natural Science:Materials International 2007年第7期17卷 845-850页

作者： Ge Xinlei~1 Wang Xidong~(1,3**) Zheng Shili~2 Zhang Mei~1 Zhang Yi~2 (1.Department of Physical chemistry,university of Science and Technology beijing,beijing 100083,china 2.Institute of Process engineering,chinese academy of sciences,beijing 100080,china 3.college of engineering,Peking university,beijing 100871,china) Department of Physical chemistry University of Science and Technology Beijing Beijing 100083 China college of engineering Peking University Beijing 100871 China Institute of Process engineering Chinese Academy of Sciences Beijing 100080 China

The phase relationships of the complex multi-component systems in the liquid-phase oxidization and separation process related with the chromate cleaner production are investigated theoretically and *** phase diagram of main system Fe- Cr2O4-KOH-O2of oxidization process and the relationship of its standard Gibbs free energy change with temperature are calculated.A se- ries of phase diagrams of the separation process at different temperatures,such as K（Na）OH-K（Na）2CrO4-H2O,KOH-KAlO2-H2O, K（Na）OH-K（Na）2CO3-H2O,K（Na）OH-K（Na）HCO3-H2O and K（Na）HCO3-K（Na）2CrO4-H2O have also been *** ex- periments are carried out to verify the calculated *** results showed that the sub-molten salt media are suitable for the oxidization and separation processes;FeCr2O4can be oxidized across a wide range of temperature;K（Na）2CrO4can be separated from K（Na）AlO2system at appropriate temperature and proper concentration;the crystallization of carbonate is easier than that of K（Na）2CrO4.

关键词： chromite chromate system thermodynamics calculation phase diagram