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Chinese Chemical Letters 1999年第12期10卷 995-998页

作者： Zhen MA Ru Dong YANG Lan YAN(Department of chemistry, lanzhou university, lanzhou, Gansu {3.) lanzhou Univ Dept Chem Lanzhou 730000 Peoples R China

The Schiff base cryptand and its cryptates were synthesized with the methods of [1+1] condensation of trialdehyde and tris(2-aminoethyl)amine and obtained in 60-65%, 5-25% and 70-80% yields respectively with or without some rare earth elements as templates. The polyoxa-aza cryptand was produced in 72% and 60-70% yields with reduction of Schiff base and its cryptates respectively.

关键词： Schiff base polyoxa-aza cryptand rare earth condensation

Solid-liquid solvent extraction of metal ions

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Journal of university of Science and Technology Beijing 2003年第3期10卷 1-7页

作者： Bo Peng, Haiyan Fan, and Jinzhang GaoDepartment of chemistry, Northwest Normal university, lanzhou 73.070,{3. Department of chemistry Northwest Normal University Lanzhou 730070 China

An overview of extraction of some trace metal ions using molten solvent (lowmelting substance) during last two decades is presented. The development of this technique since itsinception is briefly traced. The comparison of extraction efficiency, thermodynamics and kineticsmainly involving extraction of rare earth ions between molten solvent extraction at high temperatureand usual liquid-liquid extraction at room temperature are discussed in detail. The variousparameters obtained from the previous and present studies such as equilibrium extraction constantK_(ex), pH_(1/2), thermodynamic and kinetic data are displayed in tabular form. Finally, the currentdemands, disadvantages and future prospects are also evaluated.

关键词： solid-liquid solvent extraction metal ions thermodynamics kinetics determination

Determination of Trace Amount of Yttrium with Bromopyrogallol Red by solid-phase Spectrophotometry

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Rare Metals 2001年第3期20卷 202-204页

作者： Jinzhang Gao,Gang Ni, Li Yuan, Jingwan Kang Department of chemistry, Northwest Normal university, lanzhou 73.070,{3. NW Normal Univ Dept Chem Lanzhou 730070 Peoples R China

A simple and sensitive method for the determination of trace amount of yttrium by solid-phase spectrophotometry has been studied. Yttrium can form a 1 : 1 complex with bromopyrogallol red (BPR) on resin, which was determined directly at 605 nm, pH=6.5. It has a highly sensitivity (epsilon = 6.3.x 10(6)) which is 3.0-fold higher than the corresponding spectrophotometry in solution. The method was applied to the determination of yttrium in churchite.

关键词： solid-phase spectrophotometry bromopyrogallol red (BPR) yttrium

Preparation and characterization of Ni/Co bimetallic nano-clusters

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Journal of university of Science and Technology Beijing 2003年第4期10卷 46-49页

作者： Jinzhang Gao, Fei Guan, Yongjun Ma, and Jingwan KangInstitute of chemistry, Northwest Normal university, lanzhou 73.070,{3.. Inst. of Chem. Northwest Normal Univ. Lanzhou 730070 China

Ni/Co bimetallic nano-cluters have been prepared from the aqueous solution byreducing their corresponding metal salts under suitable conditions. The experimental conditionsincluding the type and concentration of protective agent, feeding order and the pH of the solutionthat influence the average particle size have been studied in detail. Transmission electronmicroscopy (TEM) indicates that the shape of those bimetallic nano-cluster particles is *** alloy structure has been shown by X-ray powder diffraction (XRD). The X-ray photoelectronspectroscopic (XPS) data have confirmed that the nickel and cobalt in the bimetallic nano-clustersare in the zero-valence state.

关键词： Ni/Co alloy chemical synthesis nano-cluster characterization

Fluorescence Enhancing Effect of OP on Ga(Ⅲ)-ECBBR system and its Analytical Application

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Rare Metals 2001年第2期20卷 130-132页

作者： Jinzhang Gao, Jianniao Tian, Yanchun Zhao, the Yang, Jingguo Hou, Jingwan Kang (chemistry and Chemical engineering College, Northwest Normal university, {3. 73.070, china) 西北师范大学甘肃兰州 730070

The fluorophotometric determination of gallium(Ⅲ) With eriochrome blue black R (ECBBR) was investigated in the presence of OP at pH 2.0n.5. The calibration graph has a good linear relationship in the rabid of 1.6×10-7-1.2× 10-5 mol/L Ga(Ⅲ). The effect of foreign ions was studied and the proposed method was applied to the determination of gallium in aluminum alloy.

关键词： gallium, eriochrome blue black R OP aluminum alloy

Two Quinones from the Aerial Parts of Sphallerocarpus gracillis

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Chinese Chemical Letters 1999年第11期10卷 919-920页

作者： Neng Yu CHEN Jun SHI Tao CHEN(Institute of Organic chemistry, State Key Laboratory of Applied Organic chemistry,lanzhou {3., lanzhou 73.000) lanzhou Univ Inst Organ Chem State Key Lab Appl Organ Chem Lanzhou 730000 Peoples R China

Two new quinones were isolated from the aerial parts of Sphallerocarpus gracillis. Their structure were determined by spectroscopic methods (HRMS.2D NMR) and finally confirmed by X-ray crystallography.

关键词： quinones Sphallerocarpus gracillis

Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science china chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2 & YIN Yingwu2,3.1. College of chemistry & Environment Protection engineering, Southwest university for Nationalities, Chengdu 610041,{3. 2. TH-UNIS Insight Co., Ltd., Beijing 100085,{3. 3. Key Laboratory of Bioorganic Phosphorus chemistry & Chemical Biology, Ministry of Education, Department of chemistry, Tsinghua university, Beijing 100084,{3. 1. College of chemistry & Environment Protection engineering Southwest University for Nationalities Chengdu 610041 China 2. TH-UNIS Insight Co. Ltd. Beijing 100085 China 3. Key Laboratory of Bioorganic Phosphorus chemistry & Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 3.%) after 2 h at 200℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

Regioselective Addition of Silyl Enolates to α, β-Unsaturated Aldehyde and its Acetal Catalyzed by MgI2 Etherate

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Chinese Chemical Letters 2003年第8期14卷 800-803页

作者： Xing Xian ZHANG, Wei Dong Z. LI* National Laboratory of Applied Organic chemistry & Institute of Organic chemistry, lanzhou university,{3. National Laboatory of Applied Organic chemistry & Institute of Organic chemistry Lanzhou University Lanzhou 730000

Regioselective addition reactions of silyl enolates to a, b-unsaturated aldehyde and its acetal catalyzed by MgI2 etherate give aldol adducts (1, 2-addition) preferentially over Michael adducts (1, 4-addition). This unique regioselectivity is distinctly different with other Lewis acidic promoters and may be attributed to the high oxyphilicity of IMg+.

关键词： MgI2 etherate silyl enolate addition regioselective.

A Study on the Driving Force for Binding of Benzene Derivatives by α-and β-Cyclodextrin

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Chinese Chemical Letters 1998年第5期9卷 463-464页

作者： Shuang Hui LUO Hui Ming JMNG You Cheng LIU(National Laboratory of Applied organic chemistry, lanzhou university, lanzhou 73.000)Qing Xiang GUO (Department of chemistry, university of Science and Technology of china, Hefei 23.026) lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China Univ Sci & Technol china Dept Chem Hefei 230026 Peoples R China

A three-dimensional diagram shows that the association constants (Ka) for the inclusionof a- and 6-CD with substitUted benzene are mainly correIated with the molar refraction (R.) andhydrophobic constant (%) of the substitUents of guest compounds. It reveals that the inclusion ofcyclodextrin with the substitUted benzene is dondnantly driYen by van der Waals forces andhydrophobic interactions.

关键词： benzene derivatives cyclodextrin driving force inclusion complexation

Simultaneously inducing synthesis of semiconductor selenium multi-armed nanorods and nanobars through bio-membrane bi-templates

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Science china chemistry 2004年第6期47卷 507-511页

作者： LI Li1, WU Qingsheng1 DING Yaping2 & LI Ping3.1. Department of chemistry, Tongji university, Shanghai 200092, china 2. Department of chemistry, Shanghai university, Shanghai 20043., china 3. Department of Food, Anhui Agricultural university, Hefei 23.03., china 1. Department of chemistry Tongji University 200092 Shanghai China 2. Department of chemistry Shanghai University 200436 Shanghai China 3. Department of Food Anhui Agricultural University 230036 Hefei China

Multi-armed nanorods and nanobars of semiconductor selenium were simultane- ously synthesized in the light of biomineralization process through bio-membrane bi-templates of rush at room temperature. The multi-armed nanorods are 60 nm in diameter and 1.5 μm in length; the nanobars are 150 nm in diameter and 1000—1100 nm in length. The XRD pattern indicates that these nanocrystals were crystallized in the hexagonal structure with lattice constants a = 0.43. nm, c = 0.495 nm. The possible formation mechanism was investigated.

关键词： selenium, multi-armed nanorods, nanobars, bio-membrane, bi-templates.