Uranium Tetrafluoride production using the dropping mercury electrode

The behaviour of electrochemically reducible single-strand polynucleotides (poly(adenylic acid)) and poly(cytidylic acid)) was studied by the differential (derivative) pulse polarography (DPP) and by other methods. Measurements were performed with the help of the dropping mercury electrode under various conditions specified by the pulse width, pulse amplitude, drop time etc. For the faradaic and tensammetric DPP peaks the diagnostic criteria were proposed which make it possible to classify even very small DPP peaks of double helical polynucleotides.

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Determination of platinum in biological material by differential pulse polarography: Analysis in urine, plasma and tissue following sample combustion

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19832903 ◽

1983 ◽

Vol 48 (10) ◽

pp. 2903-2908 ◽

Cited By ~ 16

Author(s):

Viktor Vrabec ◽

Oldřich Vrána ◽

Vladimír Kleinwächter

Keyword(s):

Biological Material ◽

Biological Fluid ◽

Mercury Electrode ◽

Differential Pulse ◽

Differential Pulse Polarography ◽

Linear Calibration ◽

Catalytic Current ◽

Pulse Polarography ◽

Dropping Mercury Electrode

A method is described for determining total platinum content in urine, blood plasma and tissues of patients or experimental animals receiving cis-dichlorodiamineplatinum(II). The method is based on drying and combustion of the biological material in a muffle furnace. The product of the combustion is dissolved successively in aqua regia, hydrochloric acid and ethylenediamine. The resulting platinum-ethylenediamine complex yields a catalytic current at a dropping mercury electrode allowing to determine platinum by differential pulse polarography. Platinum levels of c. 50-1 000 ng per ml of the biological fluid or per 0.5 g of a tissue can readily be analyzed with a linear calibration.

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The reduction of cobalt (II) ion in thiocyanate media by pulse polarography

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19830544 ◽

1983 ◽

Vol 48 (2) ◽

pp. 544-549 ◽

Cited By ~ 2

Author(s):

Jorge Alfredo Bolzan ◽

Robert Tokoro

Keyword(s):

Mercury Electrode ◽

Thiocyanate Complex ◽

Catalytic Wave ◽

Pulse Polarography ◽

Dropping Mercury Electrode ◽

Thiocyanate Concentration

The electroreduction of cobalt(II) in aqueous thiocyanate solutions at the dropping mercury electrode depends on the thiocyanate concentration. At [SCN-] = 0.3 mol/l the intermediate cobalt(I)-thiocyanate complex does exist electrokinetically and may be responsible for the appearance of a peaked catalytic wave. The predecessor species of this intermediate may be CoSCN+ and Co(SCN)2 in similarity to the behaviour of cobalt(II) with cyanide and azide ions.

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Oxidation of hydrogen peroxide at the dropping mercury electrode

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19842320 ◽

1984 ◽

Vol 49 (10) ◽

pp. 2320-2331 ◽

Cited By ~ 4

Author(s):

Miroslav Březina ◽

Martin Wedell

Keyword(s):

Hydrogen Peroxide ◽

Superoxide Anion ◽

Ph Value ◽

Mercury Electrode ◽

Electrode Process ◽

Electrochemical Processes ◽

Dropping Mercury Electrode ◽

Oxidation Of Hydrogen ◽

Decreasing Ph ◽

Rate Controlling Step

Reduction of oxygen and oxidation of hydrogen peroxide at the dropping mercury electrode are electrochemical processes strongly influenced both by the pH value and the anions in solution. With decreasing pH, both processes become irreversible, especially in the presence of anions with a negative φ2 potential of the diffusion part of the double layer. In the case of irreversible oxygen reduction, the concept that the rate-controlling step of the electrode process is the acceptance of the first electron with the formation of the superoxide anion, O2-, was substantiated. Oxidation of hydrogen peroxide becomes irreversible at a lower pH value than the reduction of oxygen. The slowest, i.e. rate-controlling step of the electrode process in borate buffers at pH 9-10 is the transfer of the second electron, i.e. oxidation of superoxide to oxygen.

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Study of the EE mechanism with adsorption of the intermediate at spherical and planar electrodes following a Langmuir’s isotherm

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19910060 ◽

1991 ◽

Vol 56 (1) ◽

pp. 60-67 ◽

Cited By ~ 3

Author(s):

María-Luisa Alcaraz ◽

Jesús Gálvez

Keyword(s):

Power Law ◽

Mercury Electrode ◽

Plane Electrode ◽

Dropping Mercury Electrode ◽

Planar Electrodes ◽

Current Potential

The theory for the EE mechanism with adsorption of the intermediate following Langmuir’s isotherm has been developed for the expanding sphere with any power law electrode model. The equations obtained with this model are general and can be applied, for example, to a stationary plane electrode, to a stationary sphere electrode, and to the two models of dropping mercury electrode (DME), expanding plane and expanding sphere. The influence exerted by the sphericity of the electrode on the current-potential (I/E) curves and the characteristics of these curves are discussed.

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Polarographic and voltammetric determination of N,N’-dinitrosopiperazine

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19911434 ◽

1991 ◽

Vol 56 (7) ◽

pp. 1434-1445 ◽

Cited By ~ 1

Author(s):

Jiří Barek ◽

Ivana Švagrová ◽

Jiří Zima

Keyword(s):

Mercury Electrode ◽

Linear Sweep Voltammetry ◽

Differential Pulse ◽

Differential Pulse Polarography ◽

Polarographic Reduction ◽

Concentration Region ◽

Pulse Polarography ◽

Chemical Efficiency ◽

Dropping Mercury Electrode

Polarographic reduction of the genotoxic N,N’-dinitrosopiperazine was studied and its mechanism was suggested. Optimum conditions were established for the determination of this substance by tast polarography over the concentration region of 1 . 10-3 to 1 . 10-6 mol l-1 and by differential pulse polarography on the conventional dropping mercury electrode or by fast scan differential pulse voltammetry and linear sweep voltammetry on a hanging mercury drop electrode over the concentration region of 1 . 10-3 to 1 . 10-7 mol l-1. Attempts at increasing further the sensitivity via adsorptive accumulation of the analyte on the surface of the hanging mercury drop failed. The methods are applicable to the testing of the chemical efficiency of destruction of the title chemical carcinogen based on its oxidation with potassium permanganate in acid solution.

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Polarographic Determination of 6-β-D-Glucopyranosyloxy-7-hydroxycoumarin

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19960333 ◽

1996 ◽

Vol 61 (3) ◽

pp. 333-341

Author(s):

Jiří Barek ◽

Roman Hrnčíř ◽

Josino C. Moreira ◽

Jiří Zima

Keyword(s):

Natural Compound ◽

Mercury Electrode ◽

Direct Determination ◽

Differential Pulse ◽

Differential Pulse Polarography ◽

Whitening Agent ◽

Polarographic Behaviour ◽

Pulse Polarography ◽

Dropping Mercury Electrode

The polarographic behaviour was studied for 6-β-D-glucopyranosyloxy-7-hydroxycoumarin, a natural compound serving as an optical whitening agent. The substance can be quantitated by tast polarography, differential pulse polarography using a conventional dropping mercury electrode, and differential pulse polarography using a static mercury drop electrode over the regions of 20-1 000, 2-1 000, and 0.2-1 000 μmol l-1, respectively. The methods developed for the quantitation of the compound were applied to its direct determination in a raw product.

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