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Electrochem.cal Behaviors of Fe^(2+) and Sm^(3+)in Urea-NaBr Low Temperature Melt and Their Inductive Codeposition

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Journal of Rare Earths 2001年第4期19卷 275-279页

作者：童叶翔刘鹏刘莉治杨绮琴 sch. of chem. and chem. eng. Zhongshan Univ. Guangzhou 510275 China

The cyclic voltammetry, chronopotentiometry and chronoamperometry were used to study the behaviors of Fe 2+ on Pt, Cu, Ag and Ti electrodes in urea NaBr melt at 373 K. Electroreduction of Fe 2+ to metallic Fe is irreversible in one step. The exchange current density determined on Ti electrode is 2 68×10 -5 A·cm -2 . Sm 3+ does not reduce to Sm alone, but can be inductively codeposited with Fe 2+ . Sm Fe alloy film contained over 90% Sm (mass fraction) can be obtained by potentiostatic electrolysis and galvanostatic electrolysis on Cu substrate. The Sm content in the alloy is related to the cathode potential, current density and the Sm 3+ /Fe 2+ molar ratio. The surface state of the Sm Fe deposit was studied by scanning electron microscopy.

关键词： rare earths Sm 3+ Fe 2+ SmFe alloy inductive codeposition diffusion coefficient exchange current density urea NaBr melt

A Good GC Stationary Phase for Separation of Xylene Isomers

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Chinese chem.cal Letters 1999年第1期10卷 45-46页

作者： Ting ZHANG Jiang Hua HAN Ruo Nong FU Jian ZHANG(sch.ol of chem.cal eng.neering & materials, Beijing institute of Technology, Beijing 100081) sch. of chem. eng. and materials Beijing Institute of Technology Beijing 100081 China

An excellent separation of xylene isomers is reported using 2, 6-O-di-pentyl-3-O-acetyl-beta-CD as capillary stationary phase. The optimum conditions for the separation are also discussed.

关键词： xylene isomers separation capillary stationary phase optimum conditions for separation

Ce^(4+)-Induced Apoptosis of Taxus cuspidata Cells in Suspension Culture

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Journal of Rare Earths 2002年第2期20卷 139-144页

作者：葛志强元英进王艳东马振毅胡宗定 Dept. of Biochem. eng. Sch. of Chem. Eng. and Technol. Tianjin Univ. Tianjin 300072 China

The standard detection hallmarks of apoptosis of Taxus cuspidata cells in suspension culture with Ce 4+ were studied. The condensation and margination of chromatin were observed under the electron microscopy. DNA fragmentation ranged 'DNA ladder' on agarose gel electrophoresis. TdT mediated dUTP nick end labeling (TUNEL) analysis of the cells reveals that the nuclear DNA strand breaks can be identified by labeling free 3′ OH termini. These results suggest that Ce 4+ can induce apoptosis of Taxus cuspidata cells and also indicate that there is a certain relationship between apoptosis and secondary metabolite product Taxol.

关键词： rare earths cerium apoptosis Taxus cuspidata cell suspension culture

Investigation of Surfactant-Stain-Metal Interaction: Naphthochrome Green/Cetyltrimethylammonium Bromide/Rare Earths Ternary Complexation

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过程工程学报 2003年第5期3卷 401-408页

作者：郑立新沈荣郜洪文 sch. chem. chem. eng. Anhui University Hefei State Key Lab. Poll. Contr. Res. Reuse. Sch. Envir. Sci. Eng. Tongji Univ.

The ternary interaction of naphthochrome green (NCG) with cetyltrimethylammonium bromide (CTAB) and rare earths (REs: Yb, Dy, Er and Eu) has been investigated with the microsurface adsorptionspectral correction technique (MSASC). The aggregation of NCG on CTAB obeys the Langmuir isothermal adsorption. The enrichment of NCG on CTAB and the presence of NaCl sensitize the complexation between REs and NCG. Both the binary aggregate and the ternary complex were characterized in the presence and absence of NaCl at pH 8.30 at 20 and 40C.

关键词：十六烷基三甲铵离子溴化物稀土配合物表面活性剂吸附 NCG

Thermocapillary motion of deformable fluid particles in tubes

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Science China Mathematics 2002年第10期45卷 1335-1350页

作者：陈晋南 sch. of chem. eng. and Mat. Science Beijing Institute of Technology Beijing 100081 China

The boundary integral technique is used to study the effect of deformation on the steady,creeping, thermocapillary migration of a fluid particle under conditions of axisymmetry, negligiblethermal convection and an insulated tube wall. The spherical radius of the fluid particle (i.e. theradius as if the particle were a sphere, a '= (3Vp'/4π)1/3, Vp'is the particle volume) and that ofthe tube are denoted, respectively, by a'and b'. For small capillary number Ca = 0.05, only for alarge fluid particle (a'/b'= 0.8) is deformation significant. For a'/b'= 0.8, hydrodynamic stressessqueeze the particle, reduce the interaction of the particle with the wall and thereby increase theterminal velocity. For small particles a'/b'＜ 0.8 and Ca = 0.05 the fluid particles translate asspheres, due to the fact that the fluid particleis too far away from the wall to be subject to distend-ing hydrodynamic stresses. The deformable particle moves faster than a spherical one in thethermocapillary migration. The increase in velocity with capillary number is larger for thermocapil-lary motion than for buoyancy.

关键词： two phase flow, fluid particle, deformable, thermocapillary migration.

An Excellent Gas Chromatographic Stationary Phase for Separation of Phenol and Cresol Isomers--Heptakis(2,6-di-O-pentyl-3-O-allyl)-β-Cyclodextrin

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Chinese chem.cal Letters 2000年第3期11卷 265-266页

作者： Yue Qin ZHANG, Xue Yan SHI, Ruo Nong FU (sch.ol of chem.cal eng.neering and materials Science. Beijing Institute of Technology, Beijing 10008) sch. of chem. eng. and Mat. Science Beijing Institute of Technology Beijing 100081 China

Heptakis(2.6-di-O-pentyl-3-O-ally)-β-cyclodextrin as an excellent gas chromatographic stationary phase separating phenol and cresol isomers is described.

关键词： Gas chromatographic stationary phase phenol and cresol isomers heptakis(2.6-di-Opentyl-3-O-allyl)-β-cyclodextrin.

Preparation of a Novel Micro/nano Tubes via Electrospun Fiber as a Template

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Journal of materials Science & Technology 2004年第5期20卷 613-616页

作者： Taiqi LIUsch.ol of materials and chem.cal eng.neering, Beijing Institute of Petro-chem.cal Technology, Beijing 102617, China sch. of Mat. and chem. eng. Beijing Inst. of Petrochem. Technol. Beijing 102617 China

Poly (para-xylylene) hollow fibers with inner diameters can be prepared via template fibers electrospun from solutions. The PPX is deposited from the vapor phase and the template fiber is selectively removed by heat treatment or solvent extraction. The PPX is partially crystalline and the crystal modification depending on the route is used to extract the template fiber. The thermal stability of the hollow fibers is only slightly reduced relative to the bulk material and the same holds for the UV-stability.

关键词： Electrospinning Fiber chem.cal vapor deposition Physical vapor deposition Crystal Conductivity

Investigation of Phosphate Cement-based Binder with Super High Early Streng.h for Repair of Concrete

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Journal of Wuhan University of Technology(materials Science) 2001年第3期16卷 46-48页

作者：姜洪义 sch. of materials Sci. and eng. Wuhan University of Technology Wuhan 430070 China

Magnesium phosphate cement-based binder(MPB)for repair of concretewas prepared by prop- ortionally mixing over burned MgO powder(M)withNHH_2PO_4 powder(P)and set modifying admixtures. It is characteristicby excellent properties such as rapid setting, high streng.h and highbond streng.h to old con- crete. The study is focused on the keyfactors influencing the setting time and streng.h of MPB, the bondproperty of MPB to old concrete and the kinetic feature of thehydration of MPB.

关键词： Repair of concrete Influencing factor property

ENVIRONMENTAL IMPACT ASSESSMENT OF CEMENT—CONCRETE SYSTEM

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Journal of Wuhan University of Technology(materials Science) 2000年第4期15卷 7-11页

作者：刘顺妮 sch. of materials Sci. and eng. Wuhan University of Technology Wuhan 430070 China

In this paper. a lije-cycle assessment methodology is used to evaluate the environmental cffects of cement-concrete system. The production factors notably affecting environment are obtained and the way in proving envi... 详细信息

关键词： lije-cycle assessment environmental effect cement-concrete system