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Objectives. Since the end of the 20th century, liquid crystals have taken a leading position as a working material for the display industry. In particular, this is due to the advances in the control of surface orientation in thin layers of liquid crystals, which is necessary for setting the initial orientation of the layer structure in the absence of an electric field. The operation of most liquid crystal displays is based on electro-optical effects, arising from the changes in the initial orientation of the layers when the electric field is turned on, and the relaxation of the orientation structure under the action of surfaces after the electric field is turned off. In this regard, the high quality of surface orientation directly affects the technical characteristics of liquid crystal displays. The traditional technology of rubbing substrates, currently used in the display industry, has several disadvantages associated with the formation of a static charge on the substrates and surface contamination with microparticles. This review discusses an alternative photoalignment technology for liquid crystals on the surface, using materials sensitive to polarization of electromagnetic irradiation. Also, this review describes various applications of photosensitive azo dyes as photo-oriented materials. Results. The alternative photoalignment technology, which employs materials sensitive to electromagnetic polarization, allows to create the orientation of liquid crystals on the surface without mechanical impact and to control the surface anchoring force of a liquid crystal. This provides the benefits of using the photoalignment technology in the display industry and photonics—where the use of the rubbing technology is extremely difficult. The optical image rewriting mechanism is discussed, using electronic paper with photo-inert and photoaligned surfaces as an example. Further, different ways of using the photoalignment technology in liquid crystal photonics devices that control light beams are described. In particular, we consider switches, controllers and polarization rotators, optical attenuators, switchable diffraction gratings, polarization image analyzers, liquid crystal lenses, and ferroelectric liquid crystal displays with increased operation speed. Conclusions. The liquid crystal photoalignment and photopatterning technology is a promising tool for new display and photonics applications. It can be used for light polarization rotation; voltage controllable diffraction; fast switching of the liquid crystal refractive index; alignment of liquid crystals in super-thin photonic holes, curved and 3D surfaces; and many more applications.

Polychloroprene is widely used as a special-purpose rubber in such industries as automotive, construction, textile industry. Chloroprene rubber takes a significant share in the market of elastomers due to its properties. In recent years, a gradual increase in demand for chloroprene rubbers is expected. This trend is most clearly seen in regions with a developed automotive industry. World leaders in the production of chloroprene rubbers and latex demonstrate their interest in increasing production capacity. In Russia, chloroprene rubber is not produced, the demand is completely met by import. In this paper, the main industrial methods for the production of chloroprene monomer, based on various feedstocks: acetylene and butadiene-1,3, exist in the world practice. Advantages and disadvantages of each of the above methods for producing chloroprene monomer are given. Technical solutions for the improvement of the chloroprene-monomer preparation technology for the steps of chlorination of butadiene-1,3 and dehydrochlorination of 3,4-dichlorobutene-1 in a column apparatus are proposed. An improved process for the preparation of chloroprene rubber from butadiene-1,3 is described. The development of a modern technology for the production of chloroprene rubber based on domestic raw materials will make it possible to obtain a high-quality target product, which will lead to the exclusion of its imports.

Kinetics of catalytic esterification of glycerol with butanoic acid on model systems was studied. Reaction orders for the reactants (butanoic acid and glycerol) were determined. They are close to 1.It was shown that the reaction order with respect to the catalyst - orthophosphoric acid - in regions where its concentration is above 0.1 mol/l is equal to zero. The estimated value of activation energy is 51.9± 8.0 kJ/mol. The results of the experiment can be used to create an industrial technological process for the synthesis of glycerol tributyrate. This compound can be used as an alternative non-phthalate plasticizer for articles made of PVC. The obtained kinetic model was validated on glycerol-containing waste of the biodiesel synthesis from renewable raw materials. The recycling of the by-product in the biofuel production with obtaining plasticizing compositions for the polymer industry can be developed on the basis of the studies.

Objectives. This paper presents research results on the encapsulation of a fluidized bed of liquid and solid toxic waste containing chemicals with a hazard class of 1–3.Methods. Soils contaminated with hexachlorobenzene and hexachlorocyclohexane were used as the seed material. Ceresin was selected as the encapsulant, which was sprayed onto the fluidized bed through a pneumatic nozzle at a temperature of 135°C. Before the spraying of the ceresin, binders were introduced into the fluidized bed of the seed material through pneumatic nozzles in the form of a melt of high-temperature coal-tar pitch and wastewater containing sodium and arsenic salts as well as heavy metal oxides. The experiments were carried out using a modified GLATT AGT-150 laboratory unit.Results. The results demonstrate that the mechanism for granule formation is a mixed mechanism. The binding of the seed material is carried out by both the pitch and salting out. In this case, the cavities in the agglomerates are partially filled with salt deposits, which increases the strength and integrity of the final product’s structure. Ranges for the process parameter values were established at the point at which there was no unwanted agglomeration in the fluidized bed, and dust formation did not exceed 5%. When the ratio of the bed mass to the mass of ceresin is equal to unity, a moisture-resistant free-flowing product of hazard class 5 is obtained, which is suitable for transportation and long-term storage. The average diameters of the initial particles and encapsulated granules were 0.5 and 1.5 mm, respectively.Conclusions. The present study demonstrates a potential process for the granulation– encapsulation of toxic waste and hazardous substances with a hazard class of 1–3 in a single fluid-bed apparatus, resulting in the formation of a moisture-resistant hazard class-5 granular product suitable for transportation and long-term storage. The results obtained can be used in the development of an industrial large-scale process for encapsulating waste of hazard classes 1–3.

Objectives.Over the last few years, medicinal chemistry research has been focusing on the creation of molecules that can target particular body systems, organs and tissues, thus abating systemic toxicity and side effects, and, most of all, boosting therapeutic potential. This goal can be achieved through the specific interaction of such drugs with active sites of cellular receptors. For example, glycoprotein receptors that can be found on cellular surfaces in neural tissues and liver parenchyma, selectively bind various glycoproteins and glycosides, facilitating their penetration into cells. This review describes how certain parameters of ligand structure (the nature and length of the spacer between carbohydrate and non-carbohydrate fragments of the molecule, number of carbohydrate residues per molecule, etc.) influence the penetration efficiency of synthetic glycoconjugates into liver cells.Methods.This review article summarizes 75 research papers and discusses data from in vitro and in vivo experiments showing which structures of synthetic carbohydrate derivatives are optimal for targeted drug delivery into liver cells.Results.The surface of liver cells (hepatocytes) contains a significant number of asialoglycoprotein receptors (ASGP-R) that are almost never found elsewhere. This makes ASGP-R an ideal target for the directed treatment of liver diseases, including such difficult, socially important conditions as hepatocellular carcinoma and Hepatitis C. A number of various ligands and targeted (to ASGP-R) delivery systems have been designed. Such molecules always contain derivatives of mono- and disaccharides, most commonly D-glucose, D-galactose, D-lactose and N-acetylglucosamines. This review contains the chemical structures of carbohydrate-based ligands.Conclusions.Glycolipids based on D-carbohydrates, when in liposomes, facilitate penetration into liver cells by a receptor-mediated, clathrin-dependent endocytosis mechanism that is activated upon contact of the carbohydrate-containing ligand fragment with the active site of ASGP-R. It can be addressed by the use of monovalent derivatives of carbohydrates as well as polyvalent glycoconjugates. Alterations in the ligand structure and the number of liposomal modifications can boost the therapeutic effect. The distance between the liposomal surface and the carbohydrate residue (spacer length), as well as the hydrophilic-lipophilic balance of the ligand molecule, have a great effect on the affinity and cellular response.

In this paper, extractive distillation flowsheets for water–formic acid–acetic acid mixtures were designed. Flowsheets not involving preliminary dehydration were considered, and the relative volatilities of the components in the presence of sulfolane were analyzed. The result of extractive distillation depends on the amount of sulfolane. The structure of the flowsheet is determined by the results of the basic ternary mixture extractive distillation. In three-column flowsheets (schemes I, II), water is isolated in the distillate of the extractive distillation column. In the second column, distillation of the formic acid–acetic acid–sulfolane mixture is carried out, yielding formic acid (90 wt %) and acetic acid (80 wt %). The recycled flow is returned to the first column. Dilution of the formic acid–acetic acid–sulfolane mixture with sulfolane (second column of flowsheet II) allows for acids of higher quality (main substance content equal to or more than 98.5 wt %) to be obtained. Flowsheet III includes four columns and two recycling stages. First, the water–formic acid mixture is isolated in the distillate of the extractive distillation column. Then, water and formic acid are separated in a two-column complex by extractive distillation, also with sulfolane. We were carrying out calculations for column working pressure 101.32 and 13.33 kPa. To prevent thermal decomposition of sulfolane, working pressure for regeneration columns was always 13.33 kPa. The extractive distillation column of the basic three-component mixture is the main factor contributing to the total energy consumption for separation (in all schemes).

A generalized algorithm for the verification of functional models and the rules for the verification of diagrams related by levels of detail were developed in this paper. The algorithm is based on the analysis of a tree which describes the decompose relations in functional diagrams. At each step of the algorithm, a pair consisting of a parent diagram and a functional diagram is selected, and the correlation of the arrows and their roles is checked for both. The formalization of the verification rules was based on the set-theoretic representation of functional diagrams in the form of labeled oriented graphs. The rules make it possible to map the position and roles of the arrows associated with the detailed function block of the parent diagram to the arrows of the child diagram. The following rules for each of the possible arrow roles were established: “input”, “output”, “control”, “mechanism”. The use of the logic programming language PROLOG was proposed for the implementation of the algorithm. A knowledge base structure comprised of 3 interrelated predicates to describe the tree of diagrams, nodes and edges of the graphs was suggested. A query to check the verification rules was formed, and methods of binding variables and fixing roles were considered. The analysis and verification of a fragment of a functional model for the production of vinyl acetate from ethylene was conducted as an example. The functional diagrams for the processes “Condensate separation” and “Vinyl acetate isolation” connected by a decompose relation were developed, their set-theoretic models were constructed, and the use of rules for the verification of each type of arrow were considered.

Trivalent gallium compounds are structural analogs of the elements with variable valency in (+3) oxidation state that can be used as cathode materials for electrochemical power devices (iron, vanadium, chromium). Literature data about gallium(III) sulfate are quite scarce. So, we developed a preparation technique for synthesizing Ga2(SO4)3 from Ga(CH3COO)2OH as a starting material. The latter was dissolved in sulfuric acid. Then gallium(III) sulfate hydrate was precipitated under cooling. The obtained precipitate is extremely hygroscopic, and it deliquesces quickly under aerobic ambient conditions. The synthesized gallium(III) sulfate hydrate was dried on the filter and then kept in vacuum at 10-2 torr for two hours to remove traces of water and acetic acid. Gallium(III) sulfate, its intermediates and products of its thermal treatment were studied by differential thermal analysis (DTA) and X-ray diffraction phase analysis. The content of crystallization water in gallium(III) sulfate hydrate was determined, and the composition of the crystallohydrate was established as Ga2(SO4)3·18H2O. (The original X-ray diffraction pattern of the latter is disclosed below in this paper.) The mentioned crystallohydrate lost its water in six steps within 40-350 °С temperature range and formed anhydrous Ga2(SO4)3, which, in turn, decomposed at 700 °С and produced nanocrystalline gallium oxide, Ga2O3. Anhydrous gallium(III) sulfate is slightly hygroscopic, so it should be stored in a desiccator. It was found that propanol-2 (isopropanol) can be used to precipitate gallium(III) sulfate from aqueous sulfuric acid: isopropanol extracts acetic acid and, thus, exhibits salting-out activity. The formed amorphous precipitate partially loses its mass when heated up to 400 °С. However, a single phase Ga2(SO4)3 specimen could not be synthesized by this method. Considering similarities between gallium and indium, it can be assumed that Ga2(SO4)3 precipitate is contaminated by gallium oxosulfate.

Nonahydro-closo-nonaborate anion possess the property of structural nonrigidity because of presence of three low-coordinated boron atoms. So it’s able to come into the reactions of polyhedral extension. This paper is devoted to the reactions of homoatomic polyhedral extension in nonahydrocloso-nonaborate anion [B9H9]2- in presence of triethylaminborane complex BH3·(C2H5)3N. It was shown that mixes of [B10H10]2- and [B12H12]2- salts in various molar ratios had been formed as products. These ratios depend on proportion of reagents. In presence of excess of triethylamin borane complex the molar ratio of products is 1:1. When equimolar amount of triethyamminborane complex used, the selectivity of process shifted to formation of [B10H10]2- anion. However the formation of [B12H12]2- still occurs in this conditions but the molar ratio of [B10H10]2-:[B12H12]2- is 5:1.