Kinetics of buccal absorption of some carboxylic acids and the correlation of the rate constants and n-heptane:aqueous phase partition coefficients

A two step operation is proposed for the biodegradation of low concentrations (< 10 mg/L) of BETX substances in an up flow submerged biotower configuration. Step 1 involves growth of a lush biofilm using benzoic acid in a batch mode. Step 2 involves a longer term biological transformation of BETX. Kinetics of biotransformations are modeled using first order assumptions, with rate constants being a function of benzoic acid dosages used in Step 1. A calibrated computer model is developed and presented to predict the degree of transformation and biomass level throughout the tower under a variety of inlet and design operational conditions.

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A general treatment for the kinetics of two consecutive irreversible first-order reactions. Determination of rate constants for the tin(II)-ion catalysed esterification of alkali metal carboxybenzenesulphonates with ethylene glycol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19781907 ◽

1978 ◽

Vol 43 (7) ◽

pp. 1907-1916 ◽

Cited By ~ 4

Author(s):

Lubomír Nondek ◽

Jaroslav Málek

Keyword(s):

Alkali Metal ◽

Ethylene Glycol ◽

Rate Constants ◽

General Treatment ◽

First Order ◽

Kinetics Of

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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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Interphase distribution of 2-furylethylenes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19851642 ◽

1985 ◽

Vol 50 (8) ◽

pp. 1642-1647 ◽

Cited By ~ 2

Author(s):

Štefan Baláž ◽

Anton Kuchár ◽

Ernest Šturdík ◽

Michal Rosenberg ◽

Ladislav Štibrányi ◽

...

Keyword(s):

Partition Coefficient ◽

Partition Coefficients ◽

Transport Rate ◽

Phase System ◽

Two Phase ◽

Interphase Distribution ◽

Distribution Kinetics ◽

System 1 ◽

Kinetics Of

The distribution kinetics of 35 2-furylethylene derivatives in two-phase system 1-octanol-water was investigated. The transport rate parameters in direction water-1-octanol (l1) and backwards (l2) are partition coefficient P = l1/l2 dependent according to equations l1 = logP - log(βP + 1) + const., l2 = -log(βP + 1) + const., const. = -5.600, β = 0.261. Importance of this finding for assesment of distribution of compounds under investigation in biosystems and also the suitability of the presented method for determination of partition coefficients are discussed.

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Kinetics of the reaction between hexamethylenediisocyanate and 1-pentanol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19833279 ◽

1983 ◽

Vol 48 (11) ◽

pp. 3279-3286

Author(s):

Slavko Hudeček ◽

Miloslav Bohdanecký ◽

Ivana Hudečková ◽

Pavel Špaček ◽

Pavel Čefelín

Keyword(s):

Liquid Chromatography ◽

Rate Constants ◽

Reversed Phase ◽

Order Reaction ◽

Second Order ◽

Second Order Reaction ◽

Reversed Phase Liquid Chromatography ◽

Consecutive Reactions ◽

Phase Liquid ◽

Kinetics Of

The reaction between hexamethylenediisocyanate and 1-pentanol in toluene was studied by means of reversed-phase liquid chromatography. By employing this method, it was possible to determine all components of the reaction mixture including both products, i.e. N-(6-isocyanate hexyl)pentylcarbamate and N,N'-bis(pentyloxycarbonyl)hexamethylenediamine. Relations for the calculation of kinetic constants were derived assuming a competitive consecutive second-order reaction. It was demonstrated that the reaction involved in this case is indeed a second-order reaction, and the rate constants of the first and second consecutive reactions were determined.

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Kinetics of esterification of monoisopropylphenols with phosphoryl trichloride

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19891311 ◽

1989 ◽

Vol 54 (5) ◽

pp. 1311-1317

Author(s):

Miroslav Magura ◽

Ján Vojtko ◽

Ján Ilavský

Keyword(s):

Liquid Phase ◽

Rate Constants ◽

Reaction Rates ◽

Activation Energies ◽

The Individual ◽

Kinetics Of

The kinetics of liquid-phase isothermal esterification of POCl3 with 2-isopropylphenol and 4-isopropylphenol have been studied within the temperature intervals of 110 to 130 and 90 to 110 °C, respectively. The rate constants and activation energies of the individual steps of this three-step reaction have been calculated from the values measured. The reaction rates of the two isomers markedly differ: at 110 °C 4-isopropylphenol reacts faster by the factors of about 7 and 20 for k1 and k3, respectively. This finding can be utilized in preparation of mixed triaryl phosphates, since the alkylation mixture after reaction of phenol with propene contains an excess of 2-isopropylphenol over 4-isopropylphenol.

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Determination of the Nucleophilicity of Tricarbonyliron Coordinated Cyclohepta-1,3,5-triene

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19991770 ◽

1999 ◽

Vol 64 (11) ◽

pp. 1770-1779 ◽

Cited By ~ 6

Author(s):

Herbert Mayr ◽

Karl-Heinz Müller

Keyword(s):

Gibbs Energy ◽

Ambient Temperature ◽

Rate Constants ◽

Second Order ◽

Order Rate ◽

Electrophilic Additions ◽

Kinetics Of

The kinetics of the electrophilic additions of four diarylcarbenium ions (4a-4d) to tricarbonyl(η4-cyclohepta-1,3,5-triene)iron (1) have been studied photometrically. The second-order rate constants match the linear Gibbs energy relationship log k20 °C = s(E + N) and yield the nucleophilicity parameter N(1) = 3.69. It is concluded that electrophiles with E ≥ -9 will react with complex 1 at ambient temperature.

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