Novel Effectively Carbonaceous and Sulfurated Hydrogen Corrosion Inhibitors on the Basis of Organosulfurphosphorus Compounds

Abstract

Novel ammonium salts of O,O-dialkyl dithiophosphoric acids were obtained by one-pot synthesis from white phosphorus, elemental sulfur, industrial alcohols or phenols, and amines. Long-chain S-alkyl O,O-dialkyldithiophosphonates were prepared by the reaction of red phosphorus with elemental sulfur, alcohols, and the cheap industrial fractions of С₁₆–С₁₈ and С₂₀–С₂₆ of higher α-olefins in the presence of Lewis acid catalyst. The dithiophosphates obtained possess the high anticorrosion activities toward mild steel.     

Complex formation between neodymium(III) and 2,2′-dipyridyl in solvents of various polarities

The interaction of neodymium(III) with 2,2′-dipyridyl (2,2′-Dipy) in solvents with permittivities of from 5 to 78 units was studied spectrophotometrically. The Nd(III): 2,2′-Dipy ratios and complex stability constants were determined. Suggestions concerning the influence of solvents on complex formation in the systems were advanced.     

Complex formation of rare-earth elements with 1,10-phenanthroline

Complex formation in a Ln(III)-1,10-phenanthroline-ethyl acetate system, where Ln = La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, or Lu, is studied by spectrophotometric methods. The stability of the complexes is estimated. The changes in the thermodynamic parameters of complex formation and the bonding character in the lanthanide complexes with 1,10-phenanthroline and 2,2′-dipyridyl are ascertained and compared.     

Spatial structure of 2,2-dimethyl-5-alkyl-1,3,2,5-dioxasilaphosphorinanes

Conclusions A study was made of the IR spectra and dipole moments of some heterocycles that simultaneously contain phosphorus and silicon atoms. The preferential conformation of the dioxasilaphosphorinanes is discussed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2129–2131, September, 1978.The authors are indebted to A. B. Remizov for the IR spectral study of 2,2,5-trimethyl-1,3,2,5-dioxasilaphosphorinane.     

Electrophoretic and gas-chromatographic analysis of an Afobazol pharmaceutical preparation

Procedures for determining 5-ethoxy-2-[2-(morpholino)ethylthio]benzimidazole dihydrochloride, an active component of the Afobazol medicinal preparation, and its potential impurities, 5-ethoxybenzimidazol-2-thione and N-(2-chloroethyl)morpholine hydrochloride by capillary zone electrophoresis in the range 2.0 × 10^?5 to 2.0 × 10^?3 M and ligand-exchange capillary electrophoresis in the range 1.0 × 10^?5 to 5.0 × 10^?3 M are developed. The optimum conditions for the separation and determination of these analytes using a quartz capillary tube are found. The reliability of the results obtained by capillary electrophoresis was confirmed by gas chromatography with a mass-selective detector.     

Sorbitol-Based Demulsifying Agents and Their Surfactant Properties

Sorbitol-based block copolymers of ethylene and propylene oxides were synthesized and characterized as surfactants and demulsifiers.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 6, 2005, pp. 966–971.Original Russian Text Copyright © 2005 by Solodov, Varnavskaya, Khvatova, Fakhrutdinov, Lebedev, Diyarov.     

Activity of Nonionic Surfactants

The surface activity of block copolymers of ethylene and propylene oxides, based on ethylenediamine, mono(ethylene glycol), and triethanolamine, was studied. Adsorption characteristics of the investigated compounds at the water-air interface are estimated.     

Complexation of europium(III) with 2,2′-dipyridyl in Eu(An)<Subscript>3</Subscript>-2,2′-dipyridyl ethyl acetate systems

Complexation of europium(III) with 2,2′-dipyridyl in Eu(An)₃-2,2′-dipyridyl-ethyl acetate systems, where An is acetylacetonate, trichloroacetate, or trifluoroacetate ions, was studied by spectrophotometric methods. The stability constants of the complexes at different temperatures were determined, and Gibbs energy, enthalpy, and entropy changes in complexation were calculated. The influence of the initial organic ligands on complexation was elucidated.