Mechanism and Kinetics of Fluorescence Quenching of Fluorene-Endcapped Butatriene: A Microspectroscopic Study of the Discrete State Constructed in Microcrystals

For the purpose of using three different types of painting materials for the inner protection of the transformer vats, their behavior was studied under actual conditions of operation in the transformer (thermal stress in electro-insulating fluid based on the natural ester in contact with copper for electro-technical use and electro-insulating paper). By comparing determination of the content in furans products (HPLC technique) and gases formed (by gas-chromatography) in the electro-insulating fluid (natural ester with high oleic content) thermally aged at 130 �C to 1000 hours in closed glass vessels, it have been found that the presence the investigated painting materials lead to a change in the mechanism and kinetics of the thermo-oxidation processes. These changes are supported by oxygen dissolved in oil, what leads to decrease both to gases formation CO2, CO, H2, CH4, C2H4 and C2H6) and furans products (5-HMF, 2-FOL, 2 -FAL and 2-ACF). The painting materials investigated during the heat treatment applied did not suffer any remarkable structural changes affecting their functionality in the electro-insulating fluid based on vegetable esters.

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Mechanism and Kinetics of the Hydrogen Failure of Thermoelectric Materials during Water Electrolysis

Russian Metallurgy (Metally) ◽

10.1134/s0036029520100146 ◽

2020 ◽

Vol 2020 (10) ◽

pp. 1102-1115

Author(s):

M. A. Korzhuev ◽

I. V. Katin ◽

M. A. Kretova ◽

E. S. Avilov

Keyword(s):

Thermoelectric Materials ◽

Water Electrolysis ◽

Mechanism And Kinetics ◽

Kinetics Of

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Spectrocoulometry – a new spectro-electrochemical technique

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19871386 ◽

1987 ◽

Vol 52 (6) ◽

pp. 1386-1396 ◽

Cited By ~ 3

Author(s):

Ján Mocák ◽

Michal Németh ◽

Mieczyslaw Lapkowski ◽

Jerzy W. Strojek

Keyword(s):

Optical Probe ◽

Optical Signal ◽

Open Circuit ◽

Electrochemical Technique ◽

Kinetics Of Oxidation ◽

Hydrolytic Reaction ◽

Experimental Errors ◽

Mechanism And Kinetics ◽

Kinetics Of

A spectrocoulometric macrocell with a direct-view optical probe was designed and constructed, where the optical signal is transferred by light-conducting glass or quartz fibres permitting to work at wavelengths above 410 or 300 nm. The method of measurement on the proposed equipment is described; it was tested in the study of the mechanism and kinetics of oxidation of Fe(bipy)32+ ions (bipy = 2,2'-bipyridyl) with the use of potentiostatic coulometric electrolysis with open-circuit relaxation at a suitable time. The primary product of electrolysis, Fe(bipy)33+, undergoes a follow-up hydrolytic reaction with the formation of a binuclear complex. The rate constant of the reaction of the first order involves the contributions, kBi, from all bases present in solution; the corresponding values for H2O, OH-, bipy, and CH3COO- ions at a ionic strength 0·5 mol dm-3 and 25 °C were determined as kOH = (5·0 ± 0·6) . 105 mol-1 dm3 s-1, kbipy = (1·3 ± 0·2) . 10-1 mol-1 dm3 s-1, kAc = (5·8 ± 1·0) . 10-2 mol-1 dm3 s-1, and kH2O is not significant with respect to experimental errors.

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New highly efficient coulometric cell with homogenous potential distribution on the working electrode

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19860636 ◽

1986 ◽

Vol 51 (3) ◽

pp. 636-642

Author(s):

Michal Németh ◽

Ján Mocák

Keyword(s):

Chemical Reactions ◽

Potential Distribution ◽

Anaerobic Conditions ◽

Highly Efficient ◽

Working Electrode ◽

Constant Potential ◽

Quantitative Analyses ◽

Mechanism And Kinetics ◽

Kinetics Of

A highly efficient coulometric cell was designed and constructed, ensuring a constant potential over the whole surface of the working electrode and suitable for very rapid electrolysis. It consists of concentric cylindrical Teflon parts; also the working and auxiliary electrodes are cylindrical and concentric. Electrolysis can be carried out under anaerobic conditions. Functioning of the cell was tested on the oxidation of hexacyanoferrate(II) and chlorpromazine and reduction of hexacyanoferrate(III). The new cell is suitable for routine quantitative analyses and in studying the mechanism and kinetics of moderately rapid chemical reactions.

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