Analysis of products of the industrial synthesis of ethylene oxide by two-dimensional gas chromatography using packed capillary columns

Procedures for separating products of the synthesis of ethylene oxide by two-column gas chromatography using both conventional capillary PLOT columns and packed capillary columns of a new type bearing microparticulated adsorbents are proposed. A combination of packed capillary columns with a microthermostat reduces both separation time and the size of the chromatographic system, which becomes compatible with microreactors. The short time of analysis enables the control over the work of a series of microreactors in a cyclic mode using one chromatographic system.     

Copper precipitation from sulfate solutions with calcium carbonates

Mechanism of interaction of copper sulfate with natural calcium carbonates, responsible for low residual copper concentrations in solutions and for the behavior of open and closed systems in storage is considered.     

Effect of hydrothermal treatment on catalytic properties of superhigh-silica zeolites

The effect of hydrothermal treatment of decationized superhigh-silica zeolite on the mechanism of n-hexane conversion has been studied. It has been established that thermosteam modification sharply decreases the cracking activity and increases the selectivity to aromatization reactions. Zeolite acidity markedly decreases, but its crystal structure does not become amorphous.

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Effect of Additions of Silica Gel and Certain Salts of Inorganic Acids on Corrosion Resistance of Cement Stone

Effect of additions of silica gel, certain salts on the rheological parameters of cement mortarand corrosion resistance of cement stone was considered.     

Structure of the products of the cyclization in acetic anhydride of β-(2-carboxy-5-chlorophenylamino) propionic acid and its nitrile

-(2-Carboxy-5-chlorophenylamino)propionic acid cyclizes in acetic anhydride to form 4-chloro-2-(2,4-dioxopiperidino)benzoic acid, which subsequently undergoes conversion into its lactone. Under the same conditions, -[acetyl(2-carboxy-5-chlorophenyl)amino]-propionitrile forms 7-chloro-1--cyanoethyl-1,2,3,4-tetrahydroquinoline-2,4-dione. The structures of the compounds obtained were confirmed by their IR, UV, and PMR spectra. An evaluation of the stability of the ketonic and enolic forms of the compounds obtained on the basis of calculations by Hückel's method has been made.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 7, pp. 879–884, July, 1970.     

Liquid-phase oxidation of bromovinyl compounds with molecular oxygen

Liquid-phase oxidation of bromovinyl compounds with the aim to obtain the corresponding α-bromo acids was studied. Original Russian Text R.B. Bayatyan, B.E. Bayatyan, L.A. Saakyan, 2006, published in Zhurnal Prikladnoi Khimii, 2006, Vol. 79, No. 11, pp. 1870–1873.