|
71.
Interrelation between Partial Reactions during Alternating-Current Polarization of Copper in Chloride Environments O. Yu. Kuksina, V. Yu. Kondrashin, and I. K. Marshakov Voronezh State University, Universitetskaya pl. 1, Voronezh, 394006 Russia e-mail:
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Received October 1, 2004 Abstract — Infralow-frequency alternating-current polarization of a copper electrode in chloride environments causes an increase in the pH of a near-electrode layer, as well as the concentration of hydroxide ions adsorbed at the electrode, during the cathodic half-period. This facilitates the oxidation of copper during the subsequent anodic half-period and changes the character of the oxidation products, that is, instead of soluble, insoluble compounds form. During the anodic half-period, consumption of hydroxide ions restores the initial pH in a near-electrode layer. The oxidation products of copper may become soluble again.
18/09/2008 | 1234 Hits | Print
|
|
72.
Kinetics of the Cu2O Chemical Decomposition during the Copper Electrochemical Oxidation in the Sulfuric-Acid-Based Electrolyte Systems A. V. Noskov, E. P. Grishina, and A. M. Pimenova Institute of Solutions Chemistry, Russian Academy of Sciences,
ul. Akademicheskaya 1, Ivanovo, 153045 Russia e-mail:
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Received May 23, 2005 Abstract — Electrochemical copper oxidation in sulfuric acid aqueous solutions and sulfate electrolytes thickened with the silicon-dioxide powder is studied potentiodynamically. Based on the current theoretical concepts, the polarization-rate dependences of the anodic current density maximum is analyzed. It is shown that these dependences can be adequately described using a porous-layer resistance model that takes into account chemical decomposition of the passivating Cu2O film formed via electrochemical mechanism. The film decomposi-tion rate constants are calculated for the studied electrolytic systems at different temperatures.
18/09/2008 | 1266 Hits | Print
|
|
73.
Electroplating Kinetics of a Nickel Tungsten Alloy V. L. Kotov and M. V. Shmukler Ivanovo State Chemical-Technological University, pr. Engelsa 7, Ivanovo, 153460 Russia e-mail:
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Received March 17, 2004 Abstract — Electroplating a nickel–tungsten alloy under various electrolysis conditions (direct and alternating current) is studied. A radical–film mechanism of the alloy formation by the cathodic deposition is experimentally proved. The effect of sorption processes at the film–electrolyte boundary on the alloy formation, as well as the possibility of controlling the film composition and structure by changing the electric field intensity, is studied. Deposits with a content of the high-melting component of up to 61% are obtained.
18/09/2008 | 1173 Hits | Print
|
|
74.
Model Concepts on the Mechanism of Microarc Oxidation of Metal Materials and the Control over This Process A. G. Rakoch, V. V. Khokhlov, V. A. Bautin, N. A. Lebedeva, Yu. V. Magurova, and I. V. Bardin Moscow State Institute of Steel and Alloys (Technological University), Leninskii pr. 4, Moscow, 119991 Russia e-mail:
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
,
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Received July 16, 2005 Abstract — Based on a critical analysis of literature data, new model concepts on the mechanism of microarc oxidation (MAO) are developed. The correctness of these model concepts is confirmed by experimental results on the average growth rate of oxide-ceramic coatings for different duration of the MAO process on   31,   2 1, and    5 alloys, the morphology of the surface structure of coatings of different thickness, the comparative electrical strength of dielectric coatings, which is assessed during self-quenching of the MAO process and in air. Equivalent electric circuits developed describe this process and are experimentally shown to be the “tool” which allows controlling MAO of aluminum and magnesium alloys.
18/09/2008 | 1185 Hits | Print
|
|
75.
Tungsten Galvanic Coatings Deposited from Salt Melts V. A. Pavlovskii Baikov Institute of Metallurgy, Russian Academy of Sciences,
Leninskii pr. 49, Moscow, 117334 Russia Received April 26, 2005
18/09/2008 | 1059 Hits | Print
|
|
76.
Dynamics of the Stress-Strained State of a Reservoir during the Corrosion of Its Shell R. K. Galimov Mel’nikov Central Research–Design Institute of Building Steel Structures,
ul. Arkhitektora Vlasova 49, Moscow, 117393 Russia e-mail:
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Received June 17, 2005 Abstract — The results of mathematical modeling of the evolution of the stress-strained state of a reservoir filled with corrosive liquid are presented.
18/09/2008 | 1030 Hits | Print
|
|
77.
The Effect of Corrosion Products on the Toxicity of Industrial Sewage K. R. Tarantseva and N. V. Firsova Penza State Technological Academy, pr. Baidukova 1-a, Penza, 440605 Russia e-mail:
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Received January 19, 2005
18/09/2008 | 989 Hits | Print
|
|
78.
Analysis of the Corrosion and Inhibitive Protection of the Lukoil Komi Oil-Fields Equipment A. P. Efremov* and S. K. Kim** * Gubkin Russian State University of Oil and Gas, Leninskii pr. 65, Moscow, 119991 Russia e-mail:
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
** Subsidiary PECHORNIPINEFT’, OOO Lukoil Komi, Russia Received May 14, 2005 Abstract — Monitoring data on the contamination by sulfate-reducing bacteria (SRB) of the pay beds of the Usinsk, Vozei, and Khar’yaga oil fields (OOO Lukoil Komi) and the corrosion state of oil-field equipment are presented. It was experimentally found that SRB affect the rate and character of the corrosion of carbon and low-allowed steels. The formulations Olazol T2P and T2PM were tested as corrosion inhibitors and bactericides in H2S-containing mineralized aqueous and two-phase media. The experience of their commercial application was generalized.
18/09/2008 | 1011 Hits | Print
|
|
79.
A Nondestructive Evaluation of the Stress Involved by the Shot Preening of Main Pipelines V. I. Bochenin and V. P. Kuznetsov Kurgan State University, Kurgan, Russia e-mail:
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Received September 29, 2004
18/09/2008 | 1065 Hits | Print
|
|
80.
The Structure of the Chromium Coatings Modified by the Dispersed Particles E. G. Vinokurov*, A. M. Arsenkin**, K. V. Grigorovich** , and V. V. Bondar’*** * Mendeleev University of Chemical Technology, Miusskaya pl. 9, Moscow, 115478 Russia ** Baikov Institute of Metallurgy and Material Sciences, Russian Academy of Sciences,
Leninskii pr. 49, Moscow, 117334 Russia *** All-Russia Institute of Scientific and Technical Information, Russian Academy of Sciences,
Baltiiskaya ul. 14, Moscow, Russia e-mail:
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
Received July 12, 2004 Abstract—The microhardness and structure of composite chromium coatings modified by dispersed CeO2 and ultradispersed diamond (UDD), as well as the granulometric UDD distribution (both in the coatings and the bath) were investigated. The presence of the particles in the coatings reduced the number of microcracks and enhanced the microhardness. Passing from the chromium to the composite coatings makes the microhardness measured on the microsections and the specimen surface converge. Despite the uniform distribution of the particles in the coatings, nonuniform distribution of their sizes is satisfactorily described by a lognormal distribu-tion function. A selective deposition of nano-size particles (with the most probable radius of UDD particles of 204 nm) was found out, although dynamic aggregates found in the solution have the most probable radius of 4530 nm. This is possibly associated with their disaggregation near the electrode and the inclusion of the finer particles into the coating.
18/09/2008 | 1113 Hits | Print
|
|
