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Journal

Materials Science and Engineering

2003

Articles 1 - 6 of 6

Full-Text Articles in Nanoscience and Nanotechnology

The Current Fluctuations Of Carbon Steel In Nano_2-Nacl Solutions, Yu-Ming Tang, Yu Zuo Nov 2003

The Current Fluctuations Of Carbon Steel In Nano_2-Nacl Solutions, Yu-Ming Tang, Yu Zuo

Journal of Electrochemistry

The characteristics of current fluctuations of A3 carbon steel in NaNO2_NaCl solutions were studied with potentiostatic and potentiodynamic polarization methods. The steel remained stable passivation in 0.1 mol/L NaNO2 solution without Cl-. After NaCl was added in to the solution, current fluctuations with a characteristic of quick increase and slow decrease occurred, indicating quick dissolution and slow re_passivation of the metastable pits. The metastable pitting may cause accumulated corrosion damage around certain area and result in observable pits. With the increase of chloride concentration, the occurring potential for metastable pits Em rised, and peak values and frequency of current fluctuations …


The Study On Carbon Nanotube-Loaded Pt Catalysts For Proton Exchange Membrane Fuel Cells, Hong Zhu, Feng-Juan Ge, Xiao-Hong Kang, Yu-Guo Yang, Yun-Hua Xu Nov 2003

The Study On Carbon Nanotube-Loaded Pt Catalysts For Proton Exchange Membrane Fuel Cells, Hong Zhu, Feng-Juan Ge, Xiao-Hong Kang, Yu-Guo Yang, Yun-Hua Xu

Journal of Electrochemistry

Carbon nanotube_supported_platinum (Pt/CNTs) and carbon_supported_platinum (Pt/C) catalysts were synthesized by in_situ chemical reduction. They were analyzed using TEM and XRD, then made into electrodes to be part of assemable PEMFC for the performence tests. The resulted show that Pt clusters in both catalysts are of small particle size (about 4nm), and Pt/CNTs exhibits a higher catalytic activity than Pt/C.


Preparation And Characterization Of Y-Type Carbon Nanotubes By Using Anodized Alumina Oxide (Aao) Template, Jing Zhang, Quan-Yong Gao, Yong Yang Nov 2003

Preparation And Characterization Of Y-Type Carbon Nanotubes By Using Anodized Alumina Oxide (Aao) Template, Jing Zhang, Quan-Yong Gao, Yong Yang

Journal of Electrochemistry

In this work, potential_modulation method was used in two_step anodization process to make an AAO template with Y_type nanochannels. Then Y_type carbon nanotubes with controlled length and branch angle were prepared in the template based on chemical vapor decomposion (CVD) method with Co particles as catalyst and C2H2 as carbon source. The Y_type nanotube branches exhibit the angle distribution ranging from 20° to 120°. The results demonstrated that the oxidation potential should be responsible for the angles and length of the branches. Short pulse and high oxidation potential will result in the short and dense nanotube branches.


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 …


Pure Iron Electrolyzed From Scrap Iron Chips And Its Corrosion Characteristics, Wei-Min Cao, Ren-He Yin, Hui-Ceng Yan, Zhi-Qiang Ye Feb 2003

Pure Iron Electrolyzed From Scrap Iron Chips And Its Corrosion Characteristics, Wei-Min Cao, Ren-He Yin, Hui-Ceng Yan, Zhi-Qiang Ye

Journal of Electrochemistry

The high purity electrolytic iron was made from scrap iron chips. Electrolytic conditions of pure iron were determined in chloride baths and the highest purity was 99.983% by chemical analysis. Pure iron had very compact texture and high mechanical strength by SEM figures of cross section. In deaerated 0.5 kmol·m-3H2SO4 and 0.5 kmol·m-3NaCl solutions, the corrosion rate of iron decreased with increasing purity.


Study For The Cathodic Behavior Of Active Chlorine On 316l Ss Electrode Surface, Hui Yu, Ming-Xian Sun, Yan Ma, Xiao-Bin Wang Feb 2003

Study For The Cathodic Behavior Of Active Chlorine On 316l Ss Electrode Surface, Hui Yu, Ming-Xian Sun, Yan Ma, Xiao-Bin Wang

Journal of Electrochemistry

The cathodic reducing reactions of active chlorine on 316L SS electrode surface have been investigated by electrochemical techniques. The open circuit potential shifted positively and the limited diffusion current density increased significantly with the increasing content of active chlorine in the 3.5%sodium chloride solution. The two cathodic reduction processes of HClO and ClO- exhibited on the surface of electrode with the active chlorine added to the 3.5%sodium chloride solution and the corresponding potentials of the two reducing reactions were confirmed. The linear relationship of the mass transport_limited Faradaic current, Id vs. the square root of the angular velocity of the …