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Study on Electrodeposition of Ho-Co Alloy in Dimethylsulfoxide

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Journal of Rare Earths 2002年第2期20卷 124-127页

作者：王宇刘冠昆童叶翔 sch. of chem. and chem. eng. Zhongshan Univ. Guangzhou 510275 China

Co deposition of Ho with Co was studied in dimethylsulfoxide (DMSO) by cyclic voltammetry and potentiostatic deposition at room temperature. The cyclic voltammogram shows that the codeposition of Ho with Co can be attributed to induced codeposition mechanism, for the codeposition potential is more negative than the deposition potential of Co but positive than that of Ho. For the potentiostatic deposition used in Ho Co alloys preparation, the results indicate that in the range of selected concentration the potential is the main factor determining the content of Ho in Ho Co alloys, while the composition of Ho 3+ and Co 2+ in electrolyte solution has less influence. According to the analysis of X ray diffraction, EDAX, and scanning electron microscopy, uniform, compact and amorphous films on Cu can be obtained at -1 8 V (***) in 0 165 mol·L -1 Ho(NO 3) -0 135 mol·L -1 CoCl 2 DMSO solution.

关键词： rare earths induced codeposition potentiostatic deposition DMSO Ho-Co alloy

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

Progress on Study of Luminescence of Rare Earth Organic Chelates

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Journal of Rare Earths 2002年第3期20卷 161-166页

作者：杨燕生安保礼龚孟濂史华红雷衡毅孟建新 sch. of chem. and chem. eng. Sun Yat-Sen Univ. Guangzhou 510275 China

Based on the investigation of the luminescence of a series of rare earth organic chelates, some relationships between luminescence and the structure of the chelates were proposed: the intensity of sensitized luminescence of central lanthanide ions(Ln 3+ ) in a rare earth organic chelate depends on (1)the suitability of the energy gap between the excited triplet energy level of the ligands and the lowest excited energy level of Ln 3+ ions; (2)the rigidity and planarity of the structure of the chelate molecule; (3)the existence of a suitable secondary ligand which may increase rigidity and the stability of the chelate molecule; and (4) the existence of a suitable π conjugated system in the chelate molecule. According to the above relationships, 25 novel organic ligands were designed and synthesized, and their lanthanide chelates were prepared. Investigation of the photoluminescence for the new chelates shows that some of the chelates are strongly luminescent, and are applied to fluoroimmunoassay for determination of human immunoglobulin(IgG), to preparation of fluorescent plastics, and to determination of growth hormone for plants. Two novel spectroscopy probe techniques for structure of coordination compounds and biological molecules were proposed and developed based on vibronic spectroscopy of Tb 3+ complexes and fluorescence of Ce 3+ .

关键词： rare earths chelate luminescence spectroscopy probes fluorescent plastics fluoroimmunoassay growth hormone

XPS Study of the Oxygen on A_2BO_4-type Compounds-A New Discovery of O_(1S) Peaks

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Chinese chem.cal Letters 1999年第12期10卷 0-0页

作者： Zhi MA Yong Ning QIN Xiao Zhou QI Fei HE(sch.ol of chem.cal eng.neering and technology, Tianjin University, Tianjin 300072) sch. of chem. eng. and technology Tianjin University Tianjin 300072 China

By means of XPS, a new O1s peak which reflects the lattice oxygen on A_2BO_4-typecompounds is discovered, suggesting that the lattice oxygen might have two energy states on thistype of material.

关键词： XPS lattice oxygen A_2BO_4-type compound.

STUDY ON CO-ELECTRODEPOSITION OF Bi-Fe ALLOY FILMS IN ORGANIC BATH

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Acta Metallurgica Sinica(eng.ish Letters) 2003年第6期16卷 507-512页

作者： G.R. Li, Y.X. Tong and G.K. Liusch.ol of chem.stry and chem.cal eng.neering, Zhongshan University, Guangzhou 510275, China sch. of chem. and chem. eng. Zhongshan Univ. Guangzhou 510275 China

The cyclic voltametry and potentiostatic electrolysis was used to investigate the preparation of Bi-Fe alloy films in LiClO4-DMSO (dimethylsulfoxide) system. The effects of several factors including the potential of deposition, current density and concentration of iron and bismuth in the solution on the Fe content in the alloy deposits were studied. Experimental results indicated that the amorphous alloy films of Bi-Fe containing Fe 4.40wt%-33.67wt% could be prepared by controlling the system composition and deposition conditions. They were gray, uniform, metallic luster and adhered firmly to the copper substrates analyzed by EDS, SEM and XRD. After heat treatment of crystallization at 270℃ for 1h, the crystal phase of Bi-Fe can be found in XRD patterns.

关键词： bismuth Bi-Fe alloy film electrodeposition DMSO (dimethyl-sulfoxide)

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

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.

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