Multiple tolerance of Rhodotorula glutinis R-1 to acid, aluminum ion and manganese ion, and its unusual ability of neutralizing acidic medium

Hydrogenation of nitrogen oxide in acid solutions on Pt-C catalysts proceeds in dependence on experimental conditions either in purely diffusion region or in the diffusion and kinetically controlled region. The boundary between these two processes shifts to the higher ratio of NO to H2 partial pressures with increasing platinum content and decreasing intensity of agitation.

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Kinetics of hydrolysis of peroxodisulphate ions in acidic medium to peroxomonosulphuric acid

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811229 ◽

1981 ◽

Vol 46 (5) ◽

pp. 1229-1236 ◽

Cited By ~ 7

Author(s):

Jan Balej ◽

Milada Thumová

Keyword(s):

Ionic Strength ◽

Rate Constants ◽

Acidic Medium ◽

Measured Data ◽

Molar Ratios ◽

Starting Solution ◽

Kinetics Of Hydrolysis ◽

Rate Of Hydrolysis ◽

Kinetics Of ◽

Hydrolysis Of

The rate of hydrolysis of S2O82- ions in acidic medium to peroxomonosulphuric acid was measured at 20 and 30 °C. The composition of the starting solution corresponded to the anolyte flowing out from an electrolyser for production of this acid or its ammonium salt at various degrees of conversion and starting molar ratios of sulphuric acid to ammonium sulphate. The measured data served to calculate the rate constants at both temperatures on the basis of the earlier proposed mechanism of the hydrolysis, and their dependence on the ionic strength was studied.

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Electrolytic reduction of o-nitrobenzyl thiocyanate in buffered solutions on mercury

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19850033 ◽

1985 ◽

Vol 50 (1) ◽

pp. 33-41 ◽

Cited By ~ 4

Author(s):

Jaromír Hlavatý

Keyword(s):

Acidic Medium ◽

Reaction Path ◽

Electrolytic Reduction ◽

Buffer System ◽

Height Ratio ◽

Preparative Electrolysis ◽

Clear Explanation ◽

Ec Mechanism ◽

Controlled Potential

The o-nitrobenzyl thiocyanate (I) behaves differently on the DME and on a large mercury pool electrode. Polarography did not give a sufficiently clear explanation of the reaction mechanism, only the preparative experiments yielded useful results. Whereas polarographic curves in solutions of Britton-Robinson buffer system with 50% by vol. ethanol exhibit two cathodic waves within the pH region 1-12, corresponding according to their height ratio to an uptake of 4 e and 2 e respectively, the controlled potential preparation electrolysis (CPE) and coulometry results indicate a more complicated reaction path. In the CPE carried out at the concentration of I 1 . 10 -2 mol/l the electroreductive splitting of CH2-SCN occurs as the first step. Nitrobenzyl radicals so formed react in the follow-up dimerization resulting in dibenzyl or toluene structures. Simultaneously or at a later stage the completion of the electrolytic reduction of the nitro group proceeds to the hydroxylamino group. In solution of 9 > pH > 1 the CPE of nitro compound I takes place by an ECEC mechanism yielding dibenzodiazocine III, its N-oxide IV and 2,2'-dimethylazoxybenzene (V). In course of preparative electrolysis in strongly acidic medium 2-amino-benzo(l,3)-thiazine-l-oxide (II) is formed by an EC mechanism.

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Racemization rates of 3,4-didehydro-2-amino acids

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19893381 ◽

1989 ◽

Vol 54 (12) ◽

pp. 3381-3386 ◽

Cited By ~ 1

Author(s):

Libor Havlíček ◽

Jan Hanuš ◽

Jan Němeček

Keyword(s):

Amino Acids ◽

Acetic Acid ◽

Acidic Medium

The racemization rates of amino acids in acidic medium (acetic acid) were studied. The sensitivity to racemization decreases in the order (E)-3,4-didehydroornithine > (E)-Nδ-Z-3,4-didehydroornithine >> (Z)-3,4-didehydronorvaline > ornithine, norvaline. (E)-3,4-Didehydroornithine is also relatively rapidly racemized on heating with 5 M or 0.05 M-HCl (100 °C).

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