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Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

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Science china chemistry 2007年第6期50卷 764-769页

作者： TANG KeWen1,2, ZHANG GuoLi2, HUANG KeLong2, LI Yuanjian3.& YI JianMin1,2 1 Department of chemistry and chemical engineering, Hunan Institute of Science and Technology, Yueyang 414000,{3. 2 college of chemistry and chemical engineering, Central South University, changsha 410083.{3. 3.college of Pharmaceutical Science, Central South University, changsha 410078,{3. Department of chemistry and chemical engineering Hunan Institute of Science and TechnologyYueyang 414000China college of chemistry and chemical {3.ing Central South UniversityChangsha 410083China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2-dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for S-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of S-CHMA in aqueous phase reached 27.6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for S-CHMA(k_S)and separation factor(alpha)are 2.44,0.89 and 2.49,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

Synthesis and purification of trialkyl compounds of gallium and indium

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Rare Metals 2002年第1期21卷 1-6页

作者： SHU Wangen, ZHOU Zhongcheng and LI Xiong chemistry and chemical engineering {3., Central South University, changsha 410083. china chemistry and chemistry engineering {3. Central South University Changsha 410083 chemistry and chemical engineering {3. Central South University Changsha 410083

The The research progress in trialkyl compounds of gallium andindium was discussed from two aspect, one was the chemical synthesisof the compounds and the other was the purification of them. Thereare three synthesis routes be- ing reported in the first aspect, *** route staring form pure metal, the route starting from the puremetal trihalides, and the electrochemical route. In the secondaspect, the purifying methods of decomposition-distillation and zonerefining were reviewed.

关键词： trialkyl compounds gallium nd indium synthesis purification

Quantitative detection of ING1 mRNA under different gene regulation based on molecular beacon

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Chinese Science Bulletin 2006年第17期51卷 2059-2064页

作者： LIU Bin1,2,3.4, WANG Kemin1,2,3.4, XIAO Zhiqiang5,6, WANG Wei1,3.4, TAN Weihong1,2,3.4, SUN Yi5,6, TANG Hongxing1,3.4 & YANG Xiaohai1,3.41. State Key Laboratory of Chemo/Biosensing and Chemometrics, Hu- nan University, changsha 4.0082, china 2. Life Science and Biotechnology Institute, Hunan University, Chang- sha 4.0082, china 3. chemistry and chemical engineer college, Hunan University, changsha 4.0082, china 4. Hunan engineering Research Center for Bio-Nanotechnology, Hunan University, changsha 4.0082, china 5. Medical Experiment Research Center, Xiangya Hospital, Central South University, changsha 410008, china 6. Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, changsha 410008, china State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha China Life Science and Biotechnology Institute Hunan University Changsha China chemistry and chemical engineer {3. Hunan University Changsha China Hunan engineering Research Center for Bio-Nanotechnology Hunan University Changsha China Medical Experiment Research Center Xiangya Hospital Central South University Changsha China Key Laboratory of Cancer Proteomics of Chinese Ministry of Health Changsha China

The effects of drug treatment, gene transfection, and p53.RNA interference (RNAi) on level of ING1 mRNA in tumor cells were quantitatively detected with the help of ING1 molecular beacon (MB)/cRNA standard curve based on MB detection technology. Results showed that the level of ING1 mRNA could be upregulated by 5-FU treatment or ING1 transfection in low expression cell line of MCF-7 and be inhibited by silencing p53.with RNAi technology in normal expression cell line of CNE2. The level of ING1 varied from 7.7×10?16 to 53.4× 10?16 mol/μg total RNA of tumor cells. The results not only provided evidence for the regulation effects of gene expression but also were applied to investigat- ing the interaction of multigenes on signal transduc- tion pathway.

关键词： ING1 RT-PCR 定量分析分子信号 mRNA

Electrochemical characteristics of amorphous MgTi_xNi(x = 0,0.1,and 0.2) hydrogen storage alloys

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Rare Metals 2010年第5期29卷 486-490页

作者： LIU Suqin,ZHAO Wenjuan,HUANG Kelong,and HUANG Hongxia college of chemistry and chemical {3.ing,Central South University,changsha 410083.china college of chemistry and chemical {3.ing Central South University Changsha China

MgTixNi （x = 0, 0.1, and 0.2） alloys were successfully prepared by mechanical alloying （MA）, and the influence of milling time on the electrochemical characteristics of the electrodes was discussed. MgTixNi alloys after 90 h milling displayed the best electrochemical performance The X-ray diffraction patterns showed that the alloy ball-milled for 90 h was amorphous with a widened diffraction peak. The charge-discharge tests indicated that these alloys had good electrochemical activation properties, and the MgTi0.2Ni alloy electrode exhibited the best cycle performance. The initial discharge capacity of the MgTi0.2Ni alloy reached up to 401.1 mAh·g^-1, and the retention rate of capacity was 3..0% after 3. cycles, much higher than that of MgNi （17.3.）. The Tafel polarization curves revealed that Ti addition could enhance the anticorrosion performance of these alloys in alkali solution, which was responsible for the ameliorated cyclic stability of these alloy electrodes.

关键词： hydrogen storage alloys titanium electrochemical properties mechanical alloying

Effects of Oxalic Acid Addition on the Hydrothermal Synthesis of Kaolinite

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Journal of Central South University 2000年第1期12卷 34-36页

作者： LIU Su qin,HUANG Ke long (college of chemistry and chemical {3.ing, Central South University of Technology, changsha 410083. china) 1. college of chemistry and chemical {3.ing Central South University of Technology 410083 Changsha China

Kaolinite was hydrothermally synthesized from alumina gel and silicate by dissolving alumina gel in oxalic acid before it was mixed with silicate, effects of the amount of addition on the species of synthetic products were discussed. The reaction product was characterized by X ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that analcite is the only phase of the reaction solution without oxalic acid, the proportion of kaolinite in product increases with the amount of addition, and kaolinite is the main species when the molar ratio of oxalic acid to alumina reaches 0.6∶1.0. This is because oxalic acid addition is beneficial to the formation of kaolinite through changing the coordination number of aluminium from four to six, while the mixture of alumina gel, before it was dissolved in oxalic acid with silicate interfered with the crystallization of kaolinite.

关键词： kaolinite hydrothermal synthesis oxalic acid

Preparation and electrochemical performance of spherical Fe_3._4 as anode materials for Li-ion batteries

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Science china(Technological Sciences) 2009年第11期52卷 3219-3223页

作者： WANG FangBin, CHEN Jie, HUANG KeLong & LIU SuQin college of chemistry & chemical {3.ing, Central South University, changsha 410083. china 1. college of chemistry & chemical {3.ing Central South University Changsha 410083 China

Fe3.4 nano-powder was prepared by the hydrothermal method. The structure and morphology of the product were characterized by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). The as-prepared powder has regularly spherical morphology, and the average size of product is about 25 nm. The possible application use of this material as the active mass of anode for rechargeable Li batteries was examined by cyclic voltammeter (CV), galvanostatic charge/*** experimental results showed that this material exhibited large specific capacity at the first cycle, and the discharge and charge capacity retention of this electrode are 3..04% and 48.76%, respectively. Furthermore, the impedance change of Fe3.4 electrode under different cycle number and potential was examined.

关键词： Fe3.4 lithium battery anode electrochemical performance

Characteristic atom arranging crystallogphy of alloy phases for Au-Cu system

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Science china(Technological Sciences) 2011年第6期54卷 1560-1567页

作者： XIE YouQing1,2,3.LIU XinBi1,2,3.PENG HongJian4,NIE YaoZhuang5,LI XiaoBo6 & LI YanFen1,2,3.1 School of Materials Science and engineering,Central South University,changsha 410083.china 2 Powder Metallurgy Research Institute,Central South University,changsha 410083.china 3.State Key Laboratory of Powder Metallurgy,Central South University,changsha 410083.china 4 School of chemistry and chemical engineering,Central South University,changsha 410083.china 5 School of Physical Science and Technique,Central South University,changsha,410083.china 6 college of Mechanical engineering,Xiangtan University,Xiangtan 411105,china 1. School of Materials Science and engineering Central South University Changsha 410083 China2. Powder Metallurgy Research Institute Central South University Changsha 410083 China3. State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China4. School of Chemistry and Chemical Engineering Central South University Changsha 410083 China5. School of Physical Science and Technique Central South University Changsha 410083 China6. College of Mechanical Engineering Xiangtan University Xiangtan 411105 China

In this paper,it is pointed out that the descriptions of alloy phase structures are dependent on structural unit *** the systematic science of alloys(SSA),the alloy phase structures are described by means of the symmetry element sequence combining with characteristic atom *** is named the characteristic atom arranging structure,which can display the characteristic atoms at the lattice sites and the micro-inhomogeneity,besides the *** characteristic atom has its own characters:neighboring configuration,potential energy,volume and electronic *** micro-inhomogeneity of alloy phases can be described by concentrations and short-range ordered parameters of characteristic *** differences between the electronic structures of alloy phases and electronic structures of characteristic atoms in the alloy phases are also discussed.

关键词： systematic science of alloys Au-Cu system alloy phase structure micro-inhomogeneity

Formation and evolution mechanisms of large-clusters during rapid solidification process of liquid metal Al

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Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 101-112页

作者： LIU Rangsu, DONG Kejun, LIU Fengxiang, ZHENG Caixing, LIU Hairong & LI Jiyong Department of Applied Physics, Hunan University, changsha 4.0082, china college of Materials Science and {3.ing, Hunan University, changsha 4.0082, china college of chemistry and chemical {3.ing, Hunan University, changsha 4.0082, china 1. Department of Applied Physics Human University 410082 Changsha China 2. college of Materials Science and engineering Hunan University 410082 Changsha China 3. college of chemistry and chemical {3.ing Hunan University 410082 Changsha China

A molecular dynamics simulation study has been performed for the formation and evolution characteristics of nano-clusters in a large-scale system consisting of 400000 atoms of liquid metal Al. The center-atom method combined with pair-bond analysis technique and cluster-type index method (CTIM) has been applied here to describe the structural configurations of various basic clusters. It is demonstrated that both the 1551 bond-type and the icosahedral cluster (12 0 12 0) constructed by 1551 bond-types are dominant among all the bond-types and cluster-types, respectively, in the system and play a critical role in the microstructure transitions of liquid metal Al. The nano-clusters (containing up to 150 atoms) are formed by the combination of some middle and small clusters with distinctly different sizes, through mutual competition by unceasing annex and evolution in a seesaw manner (in turn of obtaining and losing),which do not occur as the multi-shell structures accumulated with an atom as the center and the surrounding atoms are arranged according to a certain rule. This is the essential distinction of nano-cluster in liquid metal from those obtained by gaseous deposition, ionic spray methods, and so on. Though the nano-clusters differ from each other in shape and size, all of them possess protruding corners that could become the starting points of various dendrite structures in the solidification processes of liquid metals.

关键词： liquid metal, solidification process, large-cluster configuration, evolution mechanism, computer simulation.

Study on the Separation of Co^(2+) from Zn^(2+) , Cd^(2+) by Anion-exchange Chromatography

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Journal of Central South University 2000年第2期12卷 88-91页

作者： WANG Xin yan,ZHOU Chun shan,WANG Yan (college of chemistry and chemical {3.ing, Central South University of Technology, changsha 410083. china) 1. college of chemistry and chemical {3.ing Central South University of Technology 410083 Changsha China

The separation of Co 2+ from Zn 2+ , Cd 2+ by anion exchange chromatography was discussed. The chromatographic column containing anion resin 201×7 which was saturated with a solution of ammonium chloride. The effects of the eluant acidity and eluant composition on the separation were investigated. The results indicate that this anion exchange chromatography is suitable to the separation of Co 2+ from Zn 2+ , Cd 2+ , and the condition of separation is simple and convenient. When the column is saturated with NH 4Cl solution (2.0 mol/L, pH=4.0), the separation can be completed effectively. Zn 2+ and Cd 2+ can also be separa ted when different eluants are used and the pure solution with high concentration of Zn 2+ , Cd 2+ respectively can be obtained ea sily.

关键词： anion exchange chromatography Zn 2+ Cd 2+ Co 2+ separation