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Adsorbents used to analyze air for concentrations of various organic compounds with their subsequent determination by thermal desorption gas chromatography–mass spectrometry (GC–MS) are considered. Tenax-TA is the most commonly used material for such tasks, but it has drawbacks. The characteristics of adsorbents of Tenax, Carbosieve, Carboxen, Carbotrap, Capbopack, Porapak, Chromosorb families, XAD polymer resins, activated carbons, and some monolithic carbon materials are given. Their advantages and disadvantages for the adsorption/thermal desorption of hydrocarbons are discussed. The advantages of monolithic carbon materials and the need in the development of a new domestic material for analytical gas chromatography–thermal desorption mass spectrometry in solving oil-prospecting problems are substantiated.

—Experimental data are presented on the dynamics of quasi-adiabatic expansion of the foam formed from carbon-dioxide-plasticized polylactide in the course of fast depressurization. It is shown that, in the range of initial pressure, which corresponds to the region of transition between the subcritical and supercritical states of plasticizing agent, a substantial increase takes place in the resulting volume of the formed porous matrices. Study of the structure of synthesized matrices at the mesoscopic level provided using low-coherence reflectometry showed a dramatic difference from synthesis conditions far from the transition region. The observed features are interpreted in the framework of a qualitative model using an equation proposed by Ross to represent the foam state. The considered model takes into account the sign of increment of the internal energy of a plasticizing and foaming agent in the course of transition between the initial and final thermodynamics states of the foamed polymer.

In terms of sulfide copper–molybdenum ore of Sorsk stockwork deposit (Republic of Khakasia), the authors discuss the option of selective dissociation of minerals. The scope of the discussion embraces the effect of pulsed-discharge treatment on particle-size indexes, structural and chemical properties and floatability of objects of the study. It is shown that the pulse-discharge treatment in a greater degree influences copper sulfides and levels their floatability while surface of molybdenite undergoes minor alteration. The pulse-discharge treatment allows enhancing flotation selectivity in separation of copper sulfides and molybdenite, and promotes removal of hydrophobic molybdenite film from quartz surface, which results in production of high-quality molybdenite concentrates.

Resistance to high cycle fatigue (HCF) at room temperature and operating temperatures of the VKS-180 high-resistance steel was studied. It was found that at room temperature the test results should be schematized by a fatigue curve with inclined left and horizontal right linear segments; and at 400°C, with one linear segment. A method of determination was proposed for each case and the HCF characteristics were calculated. The related character of the fatigue failure was observed at 20 and 400°C.

Comparative evaluation of the physicochemical properties of samples of antioxidant 2,4,6-tri-tert-butylphenol, produced by different plants and used as a vulcanization inhibitor for butyl rubber-based composite material, has been carried out. An IR-spectroscopic examination of the antioxidant and its aqueous extracts and a chromatographic examination have shown that the antioxidant lots currently produced by Lipetskkhimprodukt, Limited Liability Company, differ from those previously produced by Novocherkassk Synthetic Products Plant, Open Joint-Stock Company, by the presence of amine type impurities and content of some nonidentified compounds. These impurities are specifically responsible for a decrease in the inhibiting activity of the antioxidant, revealed by an electron paramagnetic resonance examination, and for a decrease in the compound viability observed while using the verified lots of 2,4,6-tri-tert-butylphenol for direct purpose.

Glasses in the (100 − x)(0.5PbO · 0.5P2O5) · xTeO2 section of the PbO-P2O5-TeO2 system have been synthesized over the entire composition range for the first time and their properties (Raman spectra, refractive index n, density d, glass transition temperature Tg, and light scattering losses) have been investigated. It has been demonstrated that the Raman spectra can be represented as a superposition of constant spectral forms corresponding to constant stoichiometry groupings PbO · P2O5, TeO2 · 2PbO · 2P2O5, TeO2 · PbO · P2O5, 2TeO2 · PbO · P2O5, and TeO2. The existence of crystals of the corresponding stoichiometry has been predicted using the constant stoichiometry grouping concept. The diagram of the constant stoichiometry grouping contents (determined from the Raman spectra) in glasses of the system under investigation has made it possible to determine the partial properties of constant stoichiometry groupings, to calculate the dependences of the refractive index and density on the composition, and to refine the values of n and d for vitreous tellurium dioxide and lead metaphosphate. The practical importance of glasses in the system under consideration for the use in photonic devices has been discussed.

Solutions of cobalt(II) bromide in trimethyl phosphate were studied by electronic spectroscopy at 20 and 60°C.

Due to a technical error volume 53, issue 4, 2017 has been published online with an incorrect cover data. The issue has erroneously been distributed with the cover date July 2018. The correct caver date for volume 53, issue 4 should be July 2017.