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In this article, the composition and technology of combined eye drops were developed, including taurine as an anti-cataract agent and betaxolol hydrochloride as an anti-glaucoma agent. Butanol, toluene, isopropyl ether, chloroform, ammonia 25%, ethyl alcohol in various ratios were used as the mobile phase. However, these solutions and their combinations did not allow us to determine a system that makes it possible to register both active components simultaneously. Therefore, it was decided to select two thin layer chromatography systems, one of which made it possible to determine taurine, and the other betaxolol hydrochloride

Some technologies of uranium recovery from minerals involve hydrochloric acid where cationic forms of uranyl ions dominate. The work is devoted to development and testing of sorbents for removal of uranium(VI) from liquid wastes containing also an excess of Fe(III) ions. Organic-inorganic ion-exchangers based on gel-like strongly acidic resin containing zirconium hydrophosphate have been proposed for this purpose. The theoretical approach, which allows us to control a size of incorporated particles, has been applied to modification of the resin with the inorganic constituent. The results of TEM show that the samples contain mainly aggregates of nanoparticles (300 nm) or simultaneously aggregates (200 nm) and agglomerates (several microns). The synthesized organic-inorganic ion-exchangers contain from 10 to 50 mass. % of zirconium hydrophosphate. Composition and structure of the ion-exchangers affect their sorption properties. Sorption of U(VI) from modeling solutions containing also HCl and Fe(III) ions was researched under batch conditions. The initial pH of the solution was within the interval of 2–4, the sorbent dosage was 2–10 g/dm 3 . Simultaneous sorption of U(VI) and Fe(III) species was shown to occur, the removal of Fe(III) species is faster and more complete. Increasing of the sorbent dosage and the solution pH results in improvement of the efficiency of uranium (VI) removal and increase of the exchange rate. Sorption degree of uranyl cations reaches about 90 % after 3 h at pH 2 and the sorbent dosage of 10 g/dm 3 . When the sorbent dosage is 5 g/dm 3 and the solution pH is 4 the sorption degree reaches 100 % for the composite containing 10 % of the inorganic constituent. The sorption degree is lower for the materials containing higher amount of zirconium hydrophosphate. The rate of sorption has been found to obey mainly particle diffusion model. The models of chemical reaction of pseudo-first or pseudo-second order can be also applied. The composites show mainly higher sorption capacity towards U(VI) at pH 2, the pristine resin demonstrates higher capacity towards Fe(III) under these conditions. The organic-inorganic ion-exchangers can be recommended for polishing of liquid wastes which are formed during monazite processing.

In order to obtain organic-inorganic ion-exchanger, a method has been proposed involving reorganization of n gel-like cation exchange matrix in non-aqueous media followed by zirconium hydrophosphate precipitation. Reorganization, which is confirmed with methods of standard contact porosimetry and NMR 23 Na spectroscopy, means a narrowing of transport pores of the polymer. As a result of precipitation in the reorganized matrix, aggregates of zirconium hydrophosphate nanoparticles are formed. Scanning electron microscopy has shown the size of these formations to be of 200 nm in diameter. It has been found with a method of X-ray fluorescence analysis, a molar ratio of Zr:P in the inorganic constituent is 1:0.31. The regularities of precipitation are considered from the point of view of Ostwald-Freundlich and Volfkovich equations. inorganic method with a low content of phosphorus. Small size of the incorporated particles provides high rate of removal of U(VI) cationic compounds from individual aqueous solution containing also HCl (pH 2.5). The regime of sorption is mixed-diffusion, the coefficients of U(VI) → H + exchange for particle diffusion are 5.45∙10 –12 (composite), 3.86∙10 –12 (unmodified resin), 4.75∙10 –14 (individual zirconium hydrophosphate) m 2 s –1 . In the case of sorption from the solution containing also Fe(III), U(VI) sorption is complicated with a chemical reaction of the pseudo-second order. In opposite to unmodified resin, the composite removes U(VI) compounds in a wide range of the solution pH (2–10).

The kinetics of sorption of uranium(VI) compounds from sulfate and carbonate solutions using four samples of mesoporous zirconium-silica nanosorbents obtained by bitemplate (solubilization) synthesis was studied. The sorption equilibrium set-in time and the kinetic characteristics of sorption were shown to depend on the sorbent (its composition, specific surface area, dispersity, and pore size), the temperature, and the composition and pH of the solution from which uranium compounds are sorbed. The sorption kinetics was described by a first-order equation. The limiting stage of the process was found to be the external diffusion of uranium-containing particles to the sorbent surface.

The structure of a titanium iodide single crystal obtained by zone melting has been studied by metallography, X-ray diffraction, and electron microscopy. It has been shown that the initial bcc titanium single crystal becomes a pseudosingle crystal upon cooling below the temperature of the β → α polymorphic transition. The pseudosingle crystal consists of macroscopic packets, i.e., crystals of lath morphology with a size of 0.1–0.5 cm2 in different crystal sections. Each packet consists of α-phase laths of the same orientation, which are separated by dislocation boundaries. A total of six different types of packets in the pseudosingle crystal volume is realized in accordance with the Burgers orientation relationships. The structural heredity in the titanium pseudosingle crystal after the cycle of the α → β → α transformations is confirmed.

The processes of the formation of deformation and recrystallization textures in nickel alloys containing W, Mo, and Re are studied. The problems of optimizing the annealing regimes for recrystallization are considered taking into account the increase in the starting temperature of primary recrystallization in nickel alloys that contain refractory metals after rolling to large strains. The mechanical and magnetic properties of all the alloys are analyzed. The tendency of Ni95.3Mo4.7, Ni95.2W4.8, Ni95.9Re4.1, and Ni95.2Re4.8 to oxidize is studied by the thermogravimetry technique. It has been found that, of all the studied alloys, the Ni95.3Mo4.7 alloy has the best corrosion-resistant properties at high temperatures (600–700°C) and the lowest specific magnetization at working temperatures of a high-temperature superconductor.

Bitemplate (solubilization) synthesis was used to obtain new mesoporous zirconium-silica nanosorbents that can be successfully used to recover uranium compounds from sulfate and carbonate solutions.

Development of the deformation texture and recrystallization processes have been studied in some ternary nickel-based alloys of the Ni-Cr-W, Ni-Cr-Mo, and Ni-Cr-V systems. An optimum relationship between the amounts of the alloying elements upon the combined alloying of nickel has been found. Problems of the optimization of the regimes of recrystallization annealing have been considered, which are related to an increase in the temperature of the onset of primary recrystallization in ternary nickel alloys after deformation by rolling to large reductions. An analysis of mechanical and magnetic properties of all the alloys has been performed.

The structure of a zirconium iodide single crystal obtained by zone melting is studied by metallography, X-ray diffraction, and electron microscopy. It is shown that the initial pseudo single crystal consists of macroscopic hcp packets having the size of 0.3–0.8 cm2 in different crystal sections. The structural heredity in a zirconium pseudo single crystal after the cycle of the α → β → α transformations at heating and cooling rates of approximately 4–5°C/s is confirmed.

Based on the data of X-ray diffraction, electron-backscatter diffraction, dilatometry, thermal analysis, and scanning electron microscopy, we determined the optimum regimes of heat treatment of cold-rolled tape substrates of an alloy Ni88.4Cr9.2W2.4 that permit obtaining a perfect cube texture. It has been shown that the use of two-stage annealings makes it possible to obtain in this ternary nickel alloy a cube texture in which the scatter about the rolling direction (RD) and the transverse direction (TD) of the substrates varied within 6.75°–7.20° and 4.8°–5.4°, respectively.

Data on the texture, structure, and magnetic and mechanical properties of thin tape substrates made of nickel-based ternary alloys with chromium and tungsten are presented. It is established that, in Ni89.1Cr9.1W1.8 and Ni89.1Cr8.3W2.6 alloys, a sharp cube texture can be formed as a result of the primary recrystallization, which is stable up to high annealing temperatures. Using the method based on an analysis of the orientation distribution function, the ratio of main texture components that ensures the formation of the sharp cube texture in a cold-rolled tape upon the subsequent annealing has been determined. The Ni-Cr-W alloys studied have Curie temperatures below 77 K.

A comparative study of the structure and mechanical properties of single-crystal samples 〈001〉 of VKNA-1V and VKNA-4U alloys (cast and after heat treatment) has been performed using tensile tests in a temperature range of 1100–1250°C. In the case of the VKNA-4U alloy, samples of different crystallographic orientations have also been tested. At 1100°C, recrystallization was observed near the zone of fracture. The basic mechanism of relaxation at 1200–1250°C was found to be dynamic recovery. At 1250°C, the strength properties of the VKNA-4U alloy are higher than those of the VKNA-1V alloy.

Structure of an iodide zirconium single crystal prepared by zone melting has been studied by X-ray diffraction and optical and electron microscopy. It has been shown that the initial single crystal consists of macroscopic hcp packets, which are revealed by etching in crystal sections and differ in shape and dimensions (0.3–0.8 cm2). The orientation of each packet obeys the Burgers orientational relationships. Five different orientations of hcp packets of six possible variants have been found. The microstructure of each of such regions consists of a set of laths of the α phase of identical orientation separated by low-angle dislocation boundaries. The existence of structural heredity in the zirconium single crystal after a cycle of α→β→α transformations at the rate of heating and cooling on the order of 4–5 K/s has been confirmed. After quenching of a pseudo-single crystal of zirconium from a temperature of 960°C in a 10% NaCl solution, the packet structure of the α phase is retained, but the dimensions of the laths decrease severalfold.

Optical microscopy, scanning and transmission electron microscopy, X-ray diffraction, and dilatometry have been used to investigate structure formation upon the β→α (fcc-hcp) transformation in a Co-29.7% Ni alloy. During cooling of an fcc single crystal of the Co-29.7% Ni alloy to the temperature of the β→α phase transformation, the single crystal, because of the polymorphic fcc-hcp transformation, is converted into a two-phase (β + α) pseudo-single crystal. The growth direction of the crystal coincides with the crystallographic direction [112]β. It is shown that four variants of orientations of the α-martensite crystals are realized during the β→α transformation in a single crystal; the entire volume of the initial crystal is divided into packets, which contain plates of the α phase of predominantly one orientation. The thickness of the α-martensite plates determined by the method of electron microscopy is from 0.1 to 1.0 μm. After a cycle of the α→β→α transformations, in the pseudo-single crystal investigated there is observed a restoration of the initial macro- and microstructure; i.e., the fact of structural heredity is confirmed. The calculated value of the volume changes (ΔV/V) in the Co-29.7% Ni alloy upon the fcc-hcp transformation is close to that experimentally determined from dilatometric data. The hysteresis in the temperature of the onset of the β→α transformation in this alloy is 195 K.

The crystallographic parameters of the β → α transformation in oriented cobalt single crystals quenched from 1000°C have been studied by X-ray structure analysis and light microscopy. It is shown that the orientation of martensite crystals of the α phase correspond to the Wasserman orientation relationship.

The metallographic, X-ray diffraction, and electron microscopy studies of the structure of iodide zirconium single crystal obtained by the floating-zone method are carried out. It is shown that a parent single crystal consists of macroscopic hcp-packets of six different versions governed by the Burgers orientation relationships. The microstructure of each of these regions is an ensemble of laths of the α phase of identical orientation, separated by small-angle dislocation boundaries. After quenching of zirconium pseudo-single crystal from the temperature of 960°C in a 10% NaCl solution, the packet structure of the α phase survives; however, the lath sizes decrease several times.

Peculiarities of the formation of the dendritic structure and the development of alloying-component sedimentation in the Al-4% Cu alloy during its directional solidification under conditions of the earth gravitational field under pressure have been studied. It has been found that pressure substantially affects the development of alloy-component sedimentation in the two-phase zone in the case of the dendritic growth of a solid as well. The increase in the copper concentration near the lateral surface of the single crystal along the gravitational-field component, which was revealed when analyzing the nonuniformity of the solute distribution in transverse sections of a eutectic-phase sample, as well as the changes in the lattice parameter of the α solid solution, were found to be maximum during the solidification of the melt under a pressure of 0.25 and minimum under a pressure of 0.15 MPa.

We have studied regularities of floatation extraction of fine-emulsion tributyl phosphate stabilized by silicic acid. Most completely the floatation process occurs at pH 5–6. At the concentration of silicic acid 500–550 mg/dm3 the degree of floatation extraction of tributyl phosphate (α) reaches 70% (floatation time of tributyl phosphate is 10 min). In the presence of HNO3 (1–5 mol/dm3) the value α passes through the maximum at \( C_{HNO_3 } \)= 3 mol/dm3. A conclusion was made about an important role in the studied floatation process of not only electrical, but also structural-mechanical properties of the surface of the air drops and bubbles.

The texture, structure, and magnetic and mechanical properties of thin tape substrates fabricated of nickel alloys with chromium and tungsten have been investigated. It has been shown that in Ni89.6Cr8.6W1.8 and Ni89.6Cr7.8W2.6 alloys a sharp cube texture can be formed, which is stable up to high annealing temperatures. In the Ni89.2Cr7.2W3.6 alloy, other orientations are present along with a cube component. The possibility of obtaining a sharp cube texture after primary recrystallization is connected with the quantitative relationship between the texture components in a cold-rolled tape, which is determined by the method of orientation-distribution functions. The alloys studied are paramagnetic at 77 K.

X-ray diffraction analysis and atomic force microscopy were used to study the effect of the state of a substrate (an Ni-11 at % Cr ribbon) and deposition conditions on the texture and roughness of an yttrium-stabilized zirconia (YSZ) buffer layer deposited by electron-beam sputtering. The presence of a sharp cube texture in the nickel-alloy ribbon was shown to be insufficient condition for obtaining a biaxial texture in the YSZ film. A two-dimensional (2 × 2) sulfur superstructure should be formed on the nickel-ribbon surface. In this case, the YSZ film with a sharp {100} 〈100〉 cube texture and surface roughness of ∼10–15 nm can be prepared at a low deposition rate of 0.005–0.008 nm/s and a substrate temperature of 700–800°C.

The hydrogen storage capacity of titanium aluminides Ti(Al,Nb) (β0) and Ti3 (Al,Nb) (α2) subjected to mechanoactivation has been investigated. It has been found that the mechanoactivation in a hydrogen atmosphere makes it possible to obtain hydrides of titanium aluminides with a hydrogen concentration of up to 1.8 wt % at room temperature without enhanced requirements for purity and pressure of the supplied hydrogen. The release of hydrogen from such samples in a vacuum begins at a temperature of about 175°C.

Two series of samples of a Heusler alloy Ni2MnGa have been studied. The samples alloyed with iron (to 1.6 at %) and with tungsten (0.5 at %) are single-phase (L21). Alloying leads to a strengthening of the samples; during the compression tests, values of σ0.2 and σu have been found to grow. The deformation of the samples during compression increases from 2 to 5.5% in the alloy with 1.6 at % Fe and to 6.0% in the alloy with 0.5 at % W. At the concentration of 0.5 at %, the alloying with tungsten strengthens the alloy to a larger degree than alloying with iron. At the concentration 0.8 at %, no complete dissolution of tungsten in Ni2MnGa occurs. Pileups of particles of the second phase are observed, which represents a solid solution on the basis of tungsten. Temperatures of the magnetic and martensitic transformation have been determined.

Investigation has been performed of changes in the degree of long-range order (LRO) upon annealing in a temperature range of 1000–1150°C for 1 h in the cubic B2 phase of the Ti-28.2% Al-13.2% Nb-1.2% Zr-0.86% Mo alloy. The calculation carried out using X-ray diffraction data showed that the degree of LRO in the B2 phase in the three-phase field (O + α2 + B 2, T = 1000°C) is 0.36. Structure of the B2-phase regions with a low degree of LRO was studied using transmission electron microscopy. Temperature ranges suitable for thermomechanical treatment of the alloy have been determined.

The reactions of Ba2YCu3O7and Bi2Sr2CaCu2O8 + δwith salt melts were studied in the range 300–600°C with the aim of substituting alkali metals and Ag for Ba and Sr via low-temperature ion exchange. It is found that Na and K can be partially substituted on the Ba site in 123, and Ag substitutes for Sr in 2212. The incorporation of Ag has an adverse effect on the superconducting properties of 2212.

An efficient method of direct numerical simulation is proposed. The steady-state flow field generated by the impingement of a gas jet on a wall is studied as an example. The numerical results obtained during this study are in good agreement with the numerical solutions of other authors.

Pretumoral changes in the epithelium of the cervix uteri include cervical intraepithelial neoplasia (CIN). CIN III should be differentiated with regenerative changes during epidermization of endocervicoses. Epidermization is proliferation of undifferentiated reserve cells that differentiate towards the squamous epithelium, by superseding the ectopic endocervical glandular epithelium. This process was called immature squamous metaplasia (ISM). The objective of the investigation was to define the significance of different morphological signs in the differential diagnosis of CIN III and ISM. One hundred and twelve cervical, CIN III, and immature squamous metaplasia biopsies were selected for examination. The selected cervical specimens were divided into 2 groups according to the presence or absence of p16 and CK17 expression. The p16+, CK17- cases were taken as true CIN III and the pl 6-, CK17+ as a regenerative process. The basis for this investigation is the signs included by O.K. Khmelnitsky into an algorithm for the differential diagnosis of epidermizing pseudoerosion and intraepithelial cancer of the cervix uteri. The algorithm was reconsidered to objectify. The investigation established great differences in the number of significant mitoses in the study groups. A clear trend was found for differences in the number of acanthotic strands. A new differential diagnostic algorithm for CIN III and ISM, which included the number of significant mitoses and acanthotic strands and p16 and CK17 expression, was proposed.

We consider the magnetohydrodynamic (MHD) interactions of solar coronal fast shock waves of flare and/or nonflare origin with the boundaries of coronal streamers and coronal holes. Boundaries are treated as MHD tangential discontinuities (TD). Different parameters of the observed corona are used in the investigation. The general case of the oblique interaction is studied.

The self-similar problem of the oblique interaction between a fast shock wave and a tangential discontinuity is solved within the framework of the ideal magnetohydrodynamic model. The constraints on the initial parameters necessary for the existence of a regular solution are found. Various feasible wave flow patterns are found. In the space of the governing parameters boundaries between the solutions of various types are constructed. The basic features of the developing flows and their dependence on the initial data are clarified.

The adsorption behaviour of tributyl phosphate (TBP) on silica gel was studied. It was found that the adsorption isotherm shapes were complicated, being considered as S- and L-type isotherms according to the Giles classification. Adsorption itself was polymolecular and of a physical nature, the first adsorptive layer involving hydrogen bonding between the protons of surface silanol groups and the electron-donating oxygen atom of the adsorbate molecule. Subsequent adsorption layers were formed via van der Waals interaction. The free energy of adsorption of the system lay between −22.1 kJ/mol and −23.8 kJ/mol. The enthalpy change was negative and very small, i.e. −6.3 kJ/mol, while the entropy change was positive and in the range 53.9 J/(mol K) to 55.4 J/(mol K). The increase in entropy was explained in terms of the mobility of the TBP molecules in the adsorptive layer arising from their replacement on the silica gel surface by water molecules derived from the aqueous medium.

An unusual cyclodimerization reaction of the 1-methyl-1,3-diferrocenylallyl cation into 1,3,5-triferrocenyl-4-(1-ferrocenylethenyl)cyclohexene has been studied. Two isomeric compounds were isolated and their structures were established as 1,r3,c5-triferrocenyl-4-t-(1-ferrocenylethenyl)cyclohexene and 1,r3, t5-triferrocenyl-4-c-(1-ferrocenylethenyl)cyclohexene on the basis of 1H NMR and 13C NMR spectral data.