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ReaxFF molecular dynamics simulation of the cracking of the paraffin, naphthene, and aromatic components of vacuum gasoil with and without a Ni468 nanoparticle is performed. It is found that the observed routes of destruction of hydrocarbons under thermal action do not contradict the real mechanisms of thermal cracking; the enthalpies of the thermal destruction reactions of the model components obtained in ReaxFF with the CHO and NiCH force fields correlate with those determined via quantum chemistry in the ub3lyp/6-31g(d,p) DFT approximation. The mechanisms of adsorption and destruction of the paraffin, naphthene, and aromatic components of vacuum gasoil on the surface of a Ni468 nanoparticle are studied, based on the results from ReaxFF molecular dynamics simulation. Their enthalpies of adsorption and dehydrogenation are calculated, along with the activation energies of dehydrogenation on the surface of a nickel nanoparticle. Cracking in a multicomponent system consisting of 93 hydrocarbon molecules and a Ni468 nanocluster is simulated, and all routes of the destruction of the initial hydrocarbons are determined.

The quest to understand why life exhibits chirality has been far from successful. In the terrestrial theory of chirality emergence in living matter, one of the main possible mechanisms is the chiral recognition of organic molecules by enantiomorphic crystals. In this work, we studied the ability of enantiomorphic cytosine crystals, obtained by Viedma ripening, for chiral recognition by enantiomers adsorption. For this, we used MD calculations, inverse gas chromatography, and adsorption from solutions. The difference between the isotherms of enantiomers was determined using a t-test. We found that cytosine crystals were capable of chiral recognition only when the adsorbate concentration on the surface was sufficient for lateral interactions leading to layer formation. In order to approximate adsorption isotherms, Langmuir, Freundlich, BET, and Fowler–Guggenheim equations were used. The difference in lateral interactions between menthol enantiomers during their adsorption from a solution in n-heptane was established. A mechanism of chiral recognition of the adsorbed substance by cytosine crystals was proposed. The conditions under which chiral recognition could proceed were determined. We observed that, upon adsorption from a solution, chiral recognition manifested itself at higher coverages than in MD simulations. This was caused by the competitive adsorption of the solvent. The results obtained show that adsorption on enantiomorphic crystals could be the source of the first minute enantiomeric excess, providing an opportunity to understand the origin of chiral imbalance.

One of the features of the Kazakh language is the maximum differentiation of the lexical meaning, when any phenomenon is recorded, classified; a clear, precise name is given to each object, element of the system. Therefore, in the Kazakh language there are more than a dozen lexemes denoting time periods of the day, dairy products, domestic animals, a person from birth to 60 years, etc. In this paper, using the example of Russian-language journalistic texts of the Kazakh writer, publicist, translator Herold Belger, methods of semantization of the lexical meaning of Kazakh lexemes, which are actively used by the author in all of his essays, are considered. To clarify the meaning of the Kazakh lexeme, H. Belger uses translation, insertion and explanatory constructions, stringing of synonyms, etc., which contributes, according to H. Belger, to a deeper understanding of the Kazakh culture and the characteristics of the Kazakh language., Особенностью казахского языка является максимальная дифференцированность лексического значения, когда фиксируется, классифицируется любое явление, дается четкое, точное наименование каждому предмету, элементу системы. Поэтому в казахском языке имеется более десятка лексем, обозначающих временные отрезки суток, молочную продукцию, домашних животных, человека от рождения до 60 лет и т. д. Многим словам казахского языка не всегда возможно подобрать соответствие в других языках (в данном случае в русском). В данной статье на примере русскоязычных публицистических текстов казахстанского писателя, публициста, переводчика Герольда Бельгера рассматриваются способы семантизации лексического значения казахских лексем, которые активно используются автором во всех эссе. Для разъяснения значения казахской лексемы Г. Бельгер применяет перевод, вставные и пояснительные конструкции, нанизывание синонимов и др., что способствует, по мнению Г. Бельгера, более глубокому пониманию казахской культуры и особенностей казахского языка.

The article is devoted to studying the peculiarities of the worldview of the Kazakh polylingual, writer, publicist and translator Herold Belger. German was his native language, but for objective reasons, it was rarely used, and the main languages in his work and everyday life were the acquired Kazakh and Russian. Based on the material of H.Belger’s Russian-language journalism, the article reveals the initial perception of the peculiarities of the life of the Kazakh people, the gradual comprehension and complete immersion for 74 years in the Kazakh culture, the Kazakh language and literature, a peculiar perception of Kazakh reality through the eyes of a Russian German. All this is confirmed by examples of the use of Kazakh inclusions, phraseological units, comparative phrases by H.Belger in his speech, which are always accompanied for the Russian-speaking reader by translations / explanations into Russian., Статья посвящена особенностям мировосприятия казахстанского полилингва, писателя, публициста и переводчика Герольда Карловича Бельгера. Родным для него, но по объективным причинам, редко используемым был немецкий язык, а основными в работе и быту языками были приобретенные казахский и русский языки. В статье на материале русскоязычной публицистики Г.Бельгера раскрывается первоначальное восприятие особенностей быта казахского народа, постепенное постижение и полное погружение на протяжении 74-х лет в казахскую культуру, казахский язык и литературу, своеобразное восприятие казахстанской действительности глазами российского немца. Все это подтверждается примерами использования Г. Бельгером в своей речи казахских вкраплений, фразеологизмов, сравнительных оборотов, которые всегда сопровождаются для русскоязычного читателя переводами/ пояснениями на русский язык.

The sites of reactions in 5-hydroxy-6-methyluracil (HMU) and its dimeric and tetrameric associates are studied theoretically in terms of the electrostatic potential (ESP). The ESP approach allows us to construct the most stable combinations of HMU associates and to study HMU self-assembly without simulating all possible associates. A self-assembly scheme is proposed for HMU. N1–H···O1 bonds initially form between the molecules. If the first recognition center (RC) is occupied, N3–H···O2 bonds form with the participation of the third RC. The resulting ribbons with alternating contacts 1–1 and 3–3 are cross-linked through the electrostatic attraction of hydroxyl groups and the forces of dispersion between methyl groups.

The adsorption properties of UVIS-AK carbon fibers and BAU-A and SPDK-27MD carbons used for extracting phenols from water under static conditions were investigated. The adsorption equilibrium constants, monolayer capacity, characteristic adsorption energy, and change in the Gibbs energy were calculated from the adsorption isotherms.

To reveal the nature of the interaction of the optical isomers of propranolol with the surface of carbon paste electrodes modified by uracil, we performed a combined computational and experimental study. Our study comprised the different modes of complexation between propranolol and uracil molecules covering the carbon paste electrode within two approaches: molecular dynamics simulation (MD) and quantum mechanics (QM) modeling. A graphene layer was used as a model of the carbon paste electrode. The computations showed that uracil modification of the carbon paste electrode surface enhanced the selectivity toward the D-isomer of propranolol as compared to the unmodified case. These theoretical results agree with our voltammetric measurements.

Studying the self-assembly of uracil derivatives has great importance for biochemistry and nanotechnology. For example, modification of the sorbent surfaces by 5-hydroxy-6-methyluracil (HMU) enhances their adsorption activity. It is assumed that these changes are caused by the self-assembly of the network-like supramolecular associates of the uracil derivative on the sorbent surface. In the present work, the relative stabilities of 15 hydrogen-bonded dimers HMU have been studied by the TPSSh/TZVP density functional theory method and the strengths of the noncovalent interactions analyzed in terms of the reduced density gradient and natural bond orbital approaches. It was found that the symmetric dimer stabilized by two intermolecular hydrogen bonds N1–H∙∙∙O–C2 (dimer 1-1) is the most stable. This suggests that the self-assembly of HMU should occur through the intermediate formation of the dimer 1-1. The results may be useful for understanding the processes of self-assembly of the uracil derivatives and the rationalized design of the uracil-based supramolecular structures with specific properties.

Formation of new asymmetric centers with primarily the (S)-configuration was induced by the optically active center of (R)-octadec-9Z-en-7-ol upon Prilezhaev dihydroxylation. This was proved by cyclization of a 1,3-glycol system (de 26%) into the corresponding 1,3-dioxane stereoisomers.

The regioselectivity in the hydroboration-oxidation of ricinoleic acid derivatives only slightly depends on the configuration of the optically active center: the fraction of the resulting 1,3-diol is larger by 6–10% than that of the 1,4-isomer. The new asymmetric center has preferentially S configuration, as follows from the formation of the corresponding stereoisomeric 1,3-dioxane from the 1,3-diol and of 2,5-dialkyltetrahydrofuran from the 1,4-diol.

Hydroxylamine hydrochloride efficiently reduces peroxide products of olefins ozonolysis into carbonyl compounds. Depending on the substrate character, solvent, and the treatment conditions the arising aldehydes transformed along the route aldehyde→aldoxime→nitrile→ester into individual compounds or their mixtures, or give the corresponding acetals.

Ozonolysis and reduction of olefinic derivatives of ricinolic acid and L-menthol were studied using hydroxylamine hydrochloride and sodium trisacetoxyborohydride to reduce the peroxide products.

The possibility of functionalizing the alkyl part of ricinolic acid using the Barton reaction was investigated.

The synthesis of 1-palmitoyl-2,3-dioleoylglycerine, the racemic analog of a honeybee breeding pheromone component, from 1,2-O-isopropylideneglycerine was proposed.