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Analytical Chemistry

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Chinese Chemical Society | Xiamen University

Journal

2003

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

Determination Of Cystine By Second Order Differential Simple Oscillographic Voltammetry, Fu-Fang Tao, Jian-Bin Zheng Nov 2003

Determination Of Cystine By Second Order Differential Simple Oscillographic Voltammetry, Fu-Fang Tao, Jian-Bin Zheng

Journal of Electrochemistry

In 0.2 mol/L NaOH, cystine can cause an sensitive incision at -0.5 V (vs.SCE) of cathodic branch of dE/dt_E curve or second order differential simple oscillogram. Based on the oscillographic charateristic, second order differential simple oscillographic voltammetry was applied to the determination of cystine in tablet. The linear range and the detection limit for determination of cystine were 2.5×10-6~3.5×10-5 mol/L and 1.0×10-6 mol/L, respectively. The relative standard deviation for 2.000×10-5 mol/L cystine was 1.8% (n=5).


Fabrication Of Scanning Micro Cl~- Probe And In Situ Imaging Of Cl~- At The Interface Of 2024 Al Aloy/Solution, Yu-Hua Lin, Min-Hua Shao, Rong-Gang Hu, Yan Li, Rong-Gui Du, Chang-Jian Lin Aug 2003

Fabrication Of Scanning Micro Cl~- Probe And In Situ Imaging Of Cl~- At The Interface Of 2024 Al Aloy/Solution, Yu-Hua Lin, Min-Hua Shao, Rong-Gang Hu, Yan Li, Rong-Gui Du, Chang-Jian Lin

Journal of Electrochemistry

Micro combination Ag/AgCl electrode with a tip measuring tens micron in diameter was fabricated. The probe satisfied in situ imaging of Cl - distribution at metal surface in chloride solution because of its excellent linearity between potential and Cl - concentration, rapid response, good stability and selectivity. With the aid of the home made Micro Electrode Scanning system and scanning Cl - probe, the effect of the [Cl - ] at 2024_Al/solution interface on localized corrosion process was investigated. It was demonstated directly that Cl - ion in solution immigrated toward, then adsorbed preferentially and accumulated at the junction between …


Perfluorinated Sulfonic Acid Lithium Conductivity Humidity Sensor, Hong-Feng Xu, Jing Liu, Li Wan May 2003

Perfluorinated Sulfonic Acid Lithium Conductivity Humidity Sensor, Hong-Feng Xu, Jing Liu, Li Wan

Journal of Electrochemistry

Treat carbon paper with 3% PTFE solution and dried in 340 ℃ for 40 minutes to enhance its intension, and level off the surface of the carbon paper with a mixture of XC_72 carbon black and PTFE solution. With those treated carbon paper as electrodes,recast Nafion thin film from 5% Nafion solution as humidity sensitive material, a solid polymer electrolyte humidity sensor was prepared on a thin PET film.Take the relative humidity data from several saturated salt solutions, the relationship between conductivity response and relative humidity was studied at different relative humidies.The results showed: when the polymer electrolyte was H+ …


Study Of Marine Biocorrosion Using Afm And Molecular Techniques, Herbert H.P.Fang, Lichong Xu, Tong Zhang May 2003

Study Of Marine Biocorrosion Using Afm And Molecular Techniques, Herbert H.P.Fang, Lichong Xu, Tong Zhang

Journal of Electrochemistry

Biofilm is ubiquitous in nature.However,corrosin caused by biofilm is still by and large overlooked.This presentation is to demonstrate the applications of several newly developed analytical techniques in chemisrty and microbiology for the study of marine biocorrosion on steel.AFM(atomic force microscopy) was applied to investigate the initial formation mechanism of biofilm and the degree of corrosion of steel in polluted seawater.DNA/RNA_related molecular techniques were used to analyze the microbial composition corrosive biofilm. Results showed that microbial corrosion began within six days, and the corroded volume in the increased as a power function of time with an index 2.83. Most of the …


In Situ Measurements Of Solution Conductivity In Microwave Field, Yong-Qing Su, Chun-Peng Liu Feb 2003

In Situ Measurements Of Solution Conductivity In Microwave Field, Yong-Qing Su, Chun-Peng Liu

Journal of Electrochemistry

The curves of the conductivity as a function of temperature for 24 kinds of solutions have been in situ measured both in the microwave field and in absence of microwave field. The results indicated that the relationship between the conductivity in microwave field (Lw) and temperature (T) can be expressed by an equation Lw=a′+b′T+c′T2 , similar to the one that is valid in absence of the microwave field Ln=a+bT+cT2. Conductivity in the absence and presence of microwave field can be linked by the equation ln Lw=A+BLn+CL2n.