检索结果-南通市图书馆

Kinetic Studies on Forming Iso-nuclear β-type Chelates of Rare Earths with p-Sulphoaminobromophosphonazo

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2000年第12期11卷 1101-1102页

作者： Fei ZHA Li YUAN jin zhang gao Hui CHEN Chemistry&Chemical Engineering College Northwest Normal UniversityLanzhou 730070

The kinetic behavior of forming the iso-nuclear β-type chelates of rare earth ions (RE~3+) with p-sulphoaminobromophosphonazo (BPA-pSN) in ClCH2COOH-CH3COONa buffer solutions were studied by a spectrophotometric method.

关键词： β-Type chelates rare earths p-sulphoaminobromophosphonazo.\

A Novel Oscillating Chemical Reaction Using Ninhydrin as Single Organic Substrate

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第1期17卷 77-80页

作者： Fu Wei YANG jin zhang gao Wu YANG Kan Jun SUN Institute of Chemistry Northwest Normal University Lanzhou 730070

A novel oscillating chemical reaction using ninhydrin as a single organic substrate was represented in this paper. It distinguished from the classically catalyzed BZ oscillating chemical reaction due to there was no active methene （CH2=） and/or enol structure in the ninhydrin molecule, which served as single organic substrate. This suggested that the substrates used in catalyzed BZ reaction were not always the organic compounds containing active methene （CH2=） and/or enol structure and bromination process in this kind of catalyzed chemical oscillating reaction was not also necessary.

关键词： Single organic substrate active methene enol structure oscillating chemical reaction.

Study on the oscillating phenomena of electrical potential across a liquid membrane

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2007年第3期18卷 309-312页

作者： jin zhang gao Hong Xia Dai Hua Chen Jie Ren Wu Yang Chemistry ＆ Chemical Engineering College Northwest Normal University Lanzhou 730070 China

The electrical oscillations across a liquid membrane in water/oil/water system was studied with octanol as oil phase by introducing two opposite charged surfactants in oil and aqueous phase, respectively. The sustained and rhythmic oscillation was observed. To a certain extent, the features of the oscillation （e.g. induction time, frequency, life time and orientation of the pulse pikes） strongly depend on the property of surfactant, dissolved in octanol. The mechanism may be explained by the formation and destruction of dual-ion surfactant membrane accompanying with emulsification at the interface and considering the coupling effect of diffusion and associated reaction in the vicinity of the interface.

关键词： Liquid membrane Chemical oscillation Electrical potential Surfactant

Determination of Some Heavy-metal-ions Using a Sulfur Ion Modified BZ Oscillating System

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第9期17卷 1221-1224页

作者： Hua CHEN Wu YANG Hong Xia DAI Xiao Xia WEI Jie QU jin zhang gao College of Chemistry ＆ Chemical Engineering Northwest Normal University Lanzhou 730070

A highly sensitive method is developed for the determination of trace amounts of some heavy metal ions in aqueous solution based on the classical Belousov-Zhabotinskii （BZ） oscillating chemical system. Introducing of S^2- ion makes the new oscillating system Ce（SO4）2 - KBrO3 - CH2（COOH）2 - Na2S - H2SO4 have to a high sensitivity for some heavy metal ions such as Ag^＋, Pb^2＋, Hg^2＋, Cd^2＋, Cu^2＋and Bi^3＋ with detection limits down to 10^-12 mol·L^- 1

关键词： BZ oscillating system kinetic determination heavy-metal-ion sulfur ion.

A Novel Chemical Oscillator with Tyrosine as the Substrate

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2003年第12期14卷 1281-1284页

作者： Wu YANG Jie REN jin zhang gao Hua YANG Dong Yu Lv Xiu Hui LIU Institute of Chemistry Northwest Normal UniversityLanzhou 730070

A new chemical oscillating reaction system involving the manganese(II)-catalyzed reaction among potassium bromate, acetone and tyrosine in acidic medium was described in this paper. The apparent activation energy of the induction period (Ein) and that of oscillation period (Ep) were calculated, Ein=110.61KJ/mol, Ep=159.41KJ/mol. The optimum concentration of each reactant was investigated and a steady chemical oscillating system was obtained.

关键词： Chemical oscillator tyrosine substrate mechanism.

Nonlinear Behavior and Domain Feature at Oil/Water Interface

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2003年第10期14卷 1062-1065页

作者： jin zhang gao, Kan Jun SUN, Wu YANGChemistry and Chemical Engineering College, Northwest Normal University, Lanzhou 730070 Chem. and Chem. Engineering College Northwest Normal University Lanzhou 730070 China

Studies on nonlinear behavior at oil/water interface membrane were performed. This system showed rhythmic oscillations and chaos of electrical potential in a given concentration domain. The nonlinear behavior response at the liquid membrane apparently resembled that of biological chemoreceptive membrane. The possibility of developing a new type of chemical sensor with the ability to simulate substance equilibrium in living organisms was suggested in the paper.

关键词： Nonlinear behavior oscillations oil/water interface domain.

Trace determination of cobalt ion by using malic acid-malonic acid double substrate oscillating chemical system

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2008年第9期19卷 1103-1107页

作者： Jie Wang Wu Yang Jie Ren Miao Guo Xiao Dong Chen Wen Bin Wang jin zhang gao College of Chemistry ＆ Chemical Engineering Northwest Normal University Lanzhou 730070 China

A novel kinetic method for determination of trace amounts of cobalt ion was proposed and validated. The method is based on adding malic acid into classical Belousov-Zhabotinskii （B-Z） oscillating chemical system to form a double substrate one. The results showed that when the concentration of cobalt ion was in the range of 5.27× 10^-8 to 5.37 × 10^-12 mol L^-1, the change of the oscillating period was directly proportional to the negative logarithm of cobalt ion concentration. The sensitivity and precision of the developed method were quite satisfactory. The limit of detection was down to 5.20 × 10^-13 mol L^-1 which was a highest sensitivity found for determination of metal ions using oscillating chemical reaction so far. Some factors influencing the determination were also examined. The method has been successfully used to determine cobalt ion in vitamin B12 injection.

关键词： Two substrate oscillating chemical system Malic acid Cobalt Determination

Enantioseparation of some Racemic Compounds on Cellulose Tris (3,5-dimethylphenylcarbamate) Chiral Stationary Phase

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2000年第8期11卷 731-734页

作者： Xiao Qian HAN Hui Tao LIU jin zhang gao jing Guo HOU Chong Yang LI Guo Hu ZHAO Institute of Chemistry Northwest Normal UniversityLanzhou 730070 Institute of Chemistry Lanzhou UniversityLanzhou 730000

Seven chiral compounds were resolved on cellulose tris (3,5-dimethylphenylcarbamate) chiral stationary phase (CDMPC-CSP) using n-hexane/alcohol as mobile phase. Solvent strength and structural characteristics of the c... 详细信息

关键词： enantioseparation cellulose-based chiral stationary phase racemic compounds HPLC

Field test of HTS receivers on CDMA demonstration cluster in China

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2009年第4期54卷 612-615页

作者： WEI Bin GUO XuBo PIAO YunLong jin ShiChao zhang XiaoPing gao LongMa PENG HuiLi YIN ZheSheng CAO BiSong Department of Physics Tsinghua University Beijing 100084 China

This paper presents the field test of our first demonstration cluster with five base stations (BTS) on code division multiple access (CDMA) wireless communication in China, while each BTS was installed with a high temperature superconductor (HTS) receiver. The HTS receivers have the same centre frequency of 830 MHz, a bandwidth of 13 MHz, and a noise figure (NF) of 0.9 dB. After the conventional receivers in the BTSs were replaced by the HTS receivers, a consequent drive test was carried out. A 2.35 dB decrease of the mean mobile transmit power was observed in the demonstration cluster.

关键词：码分多址无线通信高温超导体 HTS滤波器 HTS接收器实地试验 CDMA