Design of oscillations across the artificial liquid membrane between water and oil phases

Nine amino acids, aspartic acid, glycine, serine, tyrosine, alanine, glutamic acid, threonine, cystine, phenylalanine, and two peptides, and two peptides, glycine-glycine peptide, glutamic acid-cystine-glycine peptide, give rise to damped oscillations of the Belousov–Zhabotinskii(BZ) type in a batch reactor. Both Mn2+ and Fe(phen)32 are essential for most of those oscillations; and the oscillations in [Mn3+] and [Fe(phen)33+] are also observed. The role of two metallic ions played in the oscillations are analyzed, showing that Mn2+ catalyzes the oxidation of the amino acids or peptides by BrO3− to produce some intermediates which effectively reduce Br2 to Br− catalyzed by Fe(phen)32+. © 1998 John Wiley & Sons, Inc. Int. J. Chem Kinet 30: 243–247, 1998.

Belousov–Zhabotinskii type oscillations with amino acids or peptides as organic substrates in the presence of Mn2+ and Fe(phen)32+ as coupled catalysts

Chapter 4 offers an extensive description of the citric acid chemistry. It includes presentation of total syntheses of citric acid, preparations of labeled citric acid, typical reactions – neutralization, degradation, oxidation, esterification, formation of anhydrides, amides, citrate-based siderophores and other compounds.

Citric Acid Chemistry

A lot of potential oscillations across oil-water interface ahve been designed by using various surfactants and biolagical surfactants in the aqueous phase and various amino acids or even polypeptides in the oil phase (nitrobenzene solution). Effects of the reactant’s concentration and the reaction temperature on the oscillating parameters have been studied. The oscillating mechanism has been discussed, and a model to the oscillating mechanism has been proposed which is proved qualitatively reasonable according to the simulation.

Potential oscillations across oil-water interface in the presence of the biological surfactant and amino acids or polypeptides

A study has been made of the influence of an electromagnetic field (EMGF) with a frequency in the 40–60 GHz range and intensity up to 4–8 mW on autowaves of concentration in the reaction of sodium bromate (0.3 M), malonic acid (0.2 M), sulfuric acid (0.45 M), and Ferroin (0.003 M). It has been found that the action of the EMGF leads to decreases in the wavelength by amounts up to 26%. The experimentally measured temperature gradient created by the EMGF in a thin layer of the reaction mixture is no greater than 0.4°K. The value calculated for the solution temperature rise that is required to create the experimentally observed decrease in wavelength is 5–6° K. It is concluded, therefore, that the observed effect cannot be explained solely by thermal action of the EMGF through heating the reaction mixture.

J.Masełko T. Tłaczala

Papers

Oscillation reactions in the system: Metabolites of krebs cycle-Mn2+-KBrO3-H2SO4