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The interaction between furosemide-palladium (Ⅱ) chelate and basic triphenylmethane dyes by resonance Rayleigh scattering spectra and resonance non-linear scattering spectra and their analytical applications

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Science china chemistry 2010年第8期53卷 1767-1777页

作者： li CuiXia,liU ShaoPu,liU ZhongFang & HU Xiaoli Key Laboratory on Luminescence and Real-Time Analysis,Ministry of Education school of chemistry and chemical engineering,southwest university,chongqing 400715,china Key Laboratory on Luminescence and Real-Time Analysis Ministry of Education school of chemistry and chemical engineering Southwest University Chongqing China

In pH 4.5-7.0 Britton-Robinson buffer solution,furosemide (FUR) reacted with Pd (II) to form a 1:1 anionic *** chelate could further react with such basic triphenylmethane dyes (BTPMD) as ethyl violet (EV),crystal violet (CV),methyl violet (MV),methyl green (MeG) and brilliant green (BG) to form 1:1 ion-association *** not only resulted in the change of absorption spectra,but also led to the significant enhancement of resonance Rayleigh scattering (RRS),second-order scattering (SOS) and frequency doubling scattering (FDS).The maximum RRS wavelengths were located at 324 nm for the EV,CV and MV system,and 340 nm for the BG and MeG *** maximum SOS wavelengths were located at 550 nm for the EV,CV,BG and MeG system,and 530 nm for the MV *** maximum scattering peaks of all the systems were at 392 nm for *** enhanced RRS,SOS and FDS intensities were directly proportional to the concentration of *** detection limits for the different dye systems were 0.3-4.9 ng mL-1 for the RRS method,3.2-33.1 ng mL-1 for the SOS method and 9.0-85.7 ng mL-1 for the FDS *** methods could be used for the determination of trace amounts of *** effects of the formation of ternary ion-association complexes on the spectral characteristics and intensities of absorption,RRS,SOS and FDS have been *** optimum conditions of these reactions,the influencing factors and the analytical properties have been *** influences of coexisting substances were tested by RRS method and the results showed that this method exhibited a high *** on the aforementioned research,the highly sensitive,simple and rapid methods for the determination of trace amounts of FUR by resonance light scattering technique have been established,which could be applied to the determination of FUR in tablet,injection,human serum and urine *** composition and structure of the ternary ion-association complex and the reaction mechanism were discusse

关键词： furosemide basic triphenylmethane dyes palladium (Ⅱ) resonance Rayleigh scattering resonance non-linear scattering

A contribution to the study of the modified Marschalk reaction:Hydroxymethylation of 6,8-O-dimethyl emodin

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Chinese chemical Letters 2010年第5期21卷 568-571页

作者： Hai Shan Jin,li Ming Zhao school of chemistry and chemical engineering,Xuzhou Normal university,Xuzhou 221116,china school of chemistry and chemical engineering Xuzhou Normal University Xuzhou 221116 China

Hydroxymethylation of 6,8-O-dimethyl emodin was easily achieved in good yields by the modified Marschalk *** influence of the amount of solvent,base and formaldehyde toward the hydroxymethylation was *** results showed that a relatively dilute reaction solution facilitated the generation of the desired 2-hydromethyl product,while the thick reaction solution benefited the generation of the methylated quinizarins.

关键词： Marschalk reaction Hydroxymethylation Emodin Antitumor activity

Preparation of new sunscreen materials Ce_(1-x)Zn_xO_(2-x) via solid-state reaction at room temperature and study on their properties

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Rare Metals 2010年第2期29卷 149-153页

作者： WU Wenwei, li Shushu, liAO Sen, XIANG Feng, and WU Xuehang school of chemistry and chemical engineering, Guangxi university, Nanning 530004, china school of chemistry and chemical engineering Guangxi University Nanning China

Superfine cerium-zinc oxides Ce1-xZnxO2-x with x = 0, 0.1, 0.3, 0.5, and 1.0 were obtained by grinding Ce（SO4）2·4H2O, ZnSO4·7H2O and NH4HCO3 under the condition of surfactant PEG-400 being present at room temperature, washing the mixture with water to remove soluble inorganic salts, drying at 80°C, and *** precursor and its calcined samples were characterized using thermogravimetry and differential thermal analyses（TG/DTA）, UV-vis absorption spectroscopy, X-ray powder diffraction（XRD）, and scanning electron microscopy（SEM）.The results showed that superfine Ce1-xZnxO2-x behaved as an excellent UV-shielding *** ZnO-doped CeO2 can facilitate the formation of crystalline state *** catalytic ability of products used in air oxidation of castor oil was *** results showed that the catalytic abilities of products decreased with increasing zinc amount.

关键词： cerium oxide zinc oxide solid-state reaction UV absorbency catalytic properties

Novel nanoporous binary Ag-Ni electrocatalysts for hydrazine oxidation

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Rare Metals 2010年第1期29卷 26-31页

作者： YI Qingfeng, li Lei, YU Wenqiang, liU Xiaoping, ZHOU Zhihua, and NIE Huidong school of chemistry and chemical engineering, Hunan university of Science and Technology, Xiangtan 411201, china school of chemistry and chemical engineering Hunan University of Science and Technology Xiangtan China

From an aqueous mixture of Ag（I）-EDTA complex and Ni（II） nitrate, silver and nickel particles were co-deposited on the surface of titanium substrates by the hydrothermal method using hydrazine hydrate as a reduction agent. The prepared titanium-supported nano-scale Ag and Ag-Ni particles （nano Ag/Ti, nano Ag86Ni14/Ti, nano Ag77Ni23/Ti, and nano Ag74Ni26/Ti） exhibit nanoporous 3D network textures. Their electrocatalytic activity towards hydrazine oxidation in alkaline solutions was evaluated by cyclic voltammetry and chronoamperometry. The results show that the four samples present a low onset potential of ca. -0.60 V vs. SCE and considerably high and stable anodic current densities for hydrazine oxidation. Among them, the nano Ag86Ni14/Ti electrode exhibits the highest anodic current density towards hydrazine oxidation, showing an increment of electro-active sites on the nano Ag86Ni14/Ti due to the addition of Ni to Ag particles.

关键词： electrocatalyst silver hydrazine oxidation fuel cell

Synthesis of a novel centipede-like copolymer of styrene and methyl methacrylate

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Science china chemistry 2007年第2期50卷 253-257页

作者： li AiXiang1 & LU ZaiJun2 1 school of Material Science and engineering,Shandong university of Technology,Zibo 255049,china 2 school of chemistry and chemical engineering,Shandong university,Jinan 250100,china school of Material Science and engineering Shandong University of Technology Zibo China school of chemistry and chemical engineering Shandong University Jinan China

A well-defined,A2B-type,centipede-like copolymer of styrene and methyl methacrylate(PS-PS-PMMA) was synthesized by the combination of living anionic polymerization and atom transfer radical polym-erization(ATRP) . The synthetic approach involves the coupling reaction of polystyrene(PS) backbone bearing 1,1-diphenylethene(DPE) pendant groups,produced by ATRP and Wittig reaction,with living polystyryllithium(PSli) ,and subsequent polymerization of the resulting 1,1-diphenylmethyl anions with methy methacrylate. The centipede-like copolymer was characterized by 1H NMR,IR,SEC,SLS,and DSC measurements.

关键词： architecture atom transfer radical polymerization centipede-like copolymer coupling reaction living anionic polymerization

Role of doping and oxygen content in superconductivity of La2 CuO4+δ

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人工智能科学与工程 1996年第5期 461-468页

作者： li Ming Huang Yuming(school of chemistry and chemical engineering, southwest china Normal university,chongqing 630715)

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关键词： superconductors La214 effect of doping and oxygen content band structure

Electrochemical behaviors of Bi (Ⅲ) in dimethylsulfoxide

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Rare Metals 2003年第2期22卷 121-124页

作者： li Gaoren, TONG Yexiang, and liU Guankunschool of chemistry and chemical engineering, Zhongshan university, Guangzhou 510275, china (Received 2002-02-28) school of chemistry and chemical engineering Zhongshands University Guangzhou 510275

Cyclic voltammetry, chronoamperometry and chronopotentiometry were used toinvestigate the electrochemical behaviors of Bi(III) in Bi(NO_3)_3-liClO_4-DMSO (dimethylsulfoxide)system on Pt and Cu electrodes. Experimental results indicated that the electroreducation of Bi(III)to Bi(0) was irreversible on Pt and Cu electrodes. The diffusion coefficient and electron transfercoefficient of Bi(III) in 0.01 mol.L^(-1) Bi(NO_3)_3-0.l mol.L^(-1) liClO_4-DMSO system at 303 Kwere 1.75 X 10^(-6) cm^2.s^1 and 0.147 respectively.

关键词： electrochemistry diffusion coefficient electrochemical behaviors DMSO(dimethylsulfoxide)

Fluorescence determination of platinum with dibromohydroxyphenyl-fluorone in microemulsion after separation and enrichment by sulfhydryl dextrose gel

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Rare Metals 2008年第1期27卷 101-105页

作者： li Huizhi ZHAI Yubo ZHAI Diantang school of chemistry and chemical engineering Jinan University Jinan 250022 China school of life Science Nanjing University Nanjing 210093 China

A new fluorescence quenching method has been developed for the determination of platinum in nonionic microemulsion *** method is based on the fact that platinum can form a stable chelate with dibromohydroxyphenyl-fluorine（DBHPF） when they are in the molar ratio of 1：2 in the nonionic microemulsion *** optimum conditions,the system,having the maximum excitation and emission wavelengths at 468 nm and 532 nm,respectively,shows constant fluorescence intensity in the pH range of 3.5-4.0 and high selectivity and sensitivity as well as low interference from foreign ***,this fluorescence intensity is a linear function of Pt（IV） concentration in the range of 0.002-1.00 μg·mL^-1 and the limit of detection is 2.90 ng·mL^-1.

关键词： analytical chemistry separation and enrichment fluorescence determination microemulsion platinum(IV)

Propane Dehydrogenation over PtSnNa Catalyst Supported on La-ZSM-5 Zeolite

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china Petroleum Processing & Petrochemical Technology 2010年第3期12卷 18-24页

作者： Huang li Zhou Yuming Zhang Yiwei li Qingning Tian Xiaoming (school of chemistry and chemical engineering,Southeast university,Nanjing 211189) school of chemistry and chemical engineering Southeast University Nanjing 211189 China

The La-ZSM-5 zeolite with different contents of La was synthesized by the hydrothermal method. The physico-chemical properties of the materials were studied. The results of FT-IR analyses indicated that La might be incorporated into the framework of ZSM-5 zeolite. The NH3-TPD analyses showed that the amount of weak acid sites of the zeolite decreased with a continuously increasing La content. Afterwards, the La-ZSM-5 zeolite was used as the support of PtSnNa catalyst for propane dehydrogenation. The test results revealed that the utilization of La- ZSM-5 zeolite could achieve a high propene conversion, and effectively inhibit the coke formation on the catalyst surface. When the content of La was 0.16%, the catalytic activity and stability of the catalyst got the best of its performance. Besides, the PtSnNa/La （0.16%）-ZSM-5 catalyst is more stable than the conventional PtSnNaLal ZSM-5 catalysts.

关键词： La-ZSM-5 propane dehydrogenation propene.