Evolutionary Development and Structural Diversity of Natural Antimicrobial Peptides,Peptidometics, and Cationic Amphiphiles Based on Amino Acids

Russian Journal of General Chemistry - The review article traces the main trends of the synthetic approach to the solution of the problem of overcoming the resistance of pathogenic bacterial...     

Interferences and Methods for Their Elimination in the Determination of Lanthanum as LaO by Laser-Enhanced Molecular Flame Ionization Spectrometry

Interfering effects of some elements on the determination of lanthanum as LaO in a natural gas–air flame by laser-enhanced molecular ionization spectrometry were studied. It was demonstrated that easily ionized elements (Li, K, Na, Mg) exert an ionization effect; in addition, sodium introduces spectral interference. Techniques were proposed for the elimination of these interfering effects.     

Photolysis of a methanolic solution of benzyl acetate in low acoustic fields

The influence of low acoustic fields on the photolysis of benzyl acetate in solution was investigated. A change in the contributions of alternative photolysis mechanisms is caused by destruction of solvate shells.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 180–181, January, 1995.This study was financially supported by the Russian Foundation for Basic Research (Project No. 93-02-18102).     

Identification of raw materials for the production of vodkas based on the results of gas-liquid chromatographic analysis with the use of fuzzy logic

The concepts of fuzzy logic were applied to the analysis of gas-chromatographic data for 12 samples of Russian vodka products. It was found that, with the use of the truth degrees of fuzzy logic propositions on the composition of analytical samples based on a simulation of expert’s reasoning, the grade of raw materials used for the production of the analytical samples can be supposed and the conformity with standards can be established.     

Electrochemical reduction of phenylethynyl halides and related compounds

Reduction of phenylethynyl halides PhCCHal (Hal = I (1), Br (2), Cl (3)), diiodoacetylene (4), (phenylethynyl)triphenylphosphonium bromide (5), and related compounds in THF was studied by means of cyclic voltammetry using a glassy-carbon electrode. Compounds1–5 are reduced with cleavage of the C-Hal bond, and the reduction potentials increase in the order3 <2 <1 <4 <5.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2055–2057, October, 1995.     

Free-Radical Gossypol Derivatives for Cotton Verticillium Wilt

The ability to bind reversibly molecular oxygen was established for a free-radical product of gossypol oxidation. Conversion of dianhydrogossypol into the stable biradical dioxodianhydrogossypol was viewed as the reason for interruption of the gossypol redox conversion cycle in the extracellular milieu of cotton steles.     

Cellulose conversion to polyols in subcritical water

Subcritical water is shown to be an efficient medium for the cellulose conversion process to produce polyols. A novel type of Ru-containing hyper-crosslinked polystyrene (HPS)-immobilized catalyst is suggested. Application of the catalyst containing 1% Ru can achieve a total yield of sorbitol and mannitol of about 50%; that is comparable with the results obtained in the presence of more complex and, therefore, more expensive catalytic systems. The influence of both the process conditions and the catalyst properties on the target product yield is studied. The hydrolytic hydrogenation of cellulose in subcritical water using Ru-containing HPS-immobilized catalysts can become a base for novel technologies of cellulose biomass conversion and production of raw materials for chemical synthesis and industrial production of second generation biofuels.     

Analysis of functionality-type distributions as a method for studying the kinetics of chemical reactions involving reactive oligomers

Critical chromatography is used to study the kinetics of reactions between polypropylene glycols and phenyl butyl isocyanate that simulate the production of polyester urethanes. The use of a two-detector version of chromatography makes it possible to monitor the concentration of the original, intermediate, and final oligomers and reveal the effect of one end group on the reactivity of the other separated by a long chain. The processing of the kinetic data makes it possible to determine the reaction-rate constants for macromolecules of different functionalities and to quantitatively describe the process behavior.