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The daily increasing demand for high-quality motor fuels requires constant improvement and modernization of existing technologies for oil refining. One of the main secondary processes of recycling hydrocarbon raw materials in industry, which allows to obtain high-octane components of automobile gasoline, valuable liquefied gases and raw materials for petrochemical industries is catalytic cracking of various types of distillate and residual raw materials. Nowadays, most catalysts of an industrial catalytic cracking contain expensive rare earth elements and platinum in its composition.

The principles of creating ion-selective electrodes for a-amino acids in a historical retrospective are considered. It is shown that until recently, when the creation of potentiometric membrane sensors, the main emphasis was made on the formation of more selective sensors able to selectively determine the concentration of some analyte in multi-component systems. The material for such sensors were ionselective membranes, which were created specific to a particular analite, but were not specific to the entire class of such analyzers.

Phase equilibria and critical phenomena in component mixtures of the cut 2 of the composition tetrahedrone of the quaternary system potassium nitrate + water + pyridine + butyric acid whose constituent ternary liquid system had a closed binodal curve were studied by means of the visual-polythermal method within 5– 60°C. We first proposed a method to find the coordinates of the end point of the critical tie line of monotectic state in quaternary systems salt + three solvents.

The formation process of quantum dots stabilized by the trioctylphosphine oxide and arachidic acid molecules mixed monolayers was studied. An equation that determines a dependence of numbers of organic matrix molecules that separates quantum dots on e from each other in the close-packing Langmuir monolayer from quantum dots size was proposed. An existence of minimal numbers of organic matrix molecules for changing and tuning a distance between quantu m dots in the Langmuir monolayer was shown.

Dipropylamine is one of the promising antisolvents for extractive salt crystallization, but its solubility in water and phase equilibria in its aqueous solutions over a wide temperature range has not been studied in detail until now. The review of the literature shows that the water-dipropylamine system is classified as a self-separating system with a lower critical solution temperature (LCST). We used the visual-polythermal method in a –25–90°C range to study phase equilibria in the binary system water-dipropylamine and to plot the phase diagram of the system.

A method is proposed for obtaining a promising cellulosecontaining oil sorbent based on the buckwheat shell and millet shell, suggesting its modification by compounds structuring the polymer followed by heat treatment. These modification methods contribute to the creation of carbon structures with controlled porosity, as well as an increase in the yield of carbonized structures after heat treatment. Sorption properties of materials based on modified plant raw materials are investigated.

The unmodified and modified by polyaniline and nanoparticles planar potentiometric sensors on the basis of tetradecylammonium associates with a complex silver (I) – cefazolin are created. Optimum ratios of components in carbon-containing ink are established: 30–32% carbon powder, 16–18% polyvinylchloride, 48–50% dibutylphthalate and 1–3% of electrode active compound (EAC). Planar sensors of two types are examined: electrode active compounds, electrode active compound and modifiers were added into in carbon-сontaining ink.

Iminodisuccinates of several rare earth metals (REM) have been synthesized as a result of reaction between freshly prepared ammonia iminodisuccinate and REM chloride soltuions at pH 3. According to element analysis data, the chemical composition of synthesized salts is MeHC8H7O8N · nH2O, where Ме = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, n = 1–5. Synthesized compounds were further analyzed via X-ray diffraction and thermogravimetric analysis. According to X-ray data, REM iminodissucinates form well-defined crystals in two distinct isostructural groups.

Higher fungi – basidiomycetes play significant role as food and biological subjects for establishing the regularities of the living systems’ operation, development and response to the different-nature effectors impact. Insufficient activity of the living organisms’ antioxidant system interfering the ability of overcoming the negative consequences of oxidative stress (excessive level of free radicals in cells) is believed to be a reason for the organisms aging and death.