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Results are presented from pendant and sessile drop measurements of the dependence of surface tension σ of aqueous suspensions of bentonites on the period of surface formation. It is established that the sedimentation of particles is the most important factor affecting the accuracy and reproducibility of measurements of σ in suspensions of bentonites. A procedure is proposed that neutralizes the effect this factor has on the value of σ. Ways of measuring σ in which sedimentation is directed differently relative to the surface are used. Sedimentation is thus directed to the surface in the pendant drop approach, and away from the surface in the sessile drop technique. Measuring σ in these ways and averaging the results considerably reduces the error caused by sedimentation. Analysis of the concentration dependence of σ on the suspensions of bentonite shows that the sedimentation factor is almost completely eliminated when using this procedure.

A study is performed of the advantages and disadvantages of different ways of determining adsorption that differ only in how the position of a dividing surface is fixed. Formulas are obtained and the concentration dependence of the distance between different positions of a Gibbs dividing surface (V and M in Gibbs’ version; N in those of Guggenheim–Adam variants) is calculated for indium–tin, gallium–bismuth, and thallium–bismuth binary systems. The results from calculations show that the concentration dependence of this distance is complex (there are extrema in the form of a maximum and minimum). Contrary to existing opinion, however, the considered positions of a Gibbs dividing surface do not move apart much upon a change in the composition of the solution. The maximum distance between different positions of a dividing surface in the studied systems thus does not exceed the size of atoms (i.e., it remains within the thickness of the monolayer). This distance in the studied systems therefore does not exceed the dimensions of the effective thickness of the surface layer.

Fabrication of composites based on micro- and nanostructured hybrid polymers have been studied. A new technology for nanoparticle immobilization in the polymer matrix of the composite has been suggested. Its essence is to produce functional electronegative polymer segments in the polymer matrix, which are the main agents preventing nanoparticle mobilization in the polymer phase of a composite.

The results of the experimental and theoretical studies of the concentration dependence of surface tension of aqueous solutions of the 1,4-dioxane–acetone–water and glycerol–ethanol–water ternary systems were given. The studies were performed by the hanging-drop method on a DSA100 tensiometer. The maximum error of surface tension was 1%. The theoretical models for calculating the surface tension of the ternary systems of organic solutions were analyzed.

The influence of the electronegativity of phases, which is controlled by composite crystallization under the conditions of the effect of the electric discharge and covalence of piezophase cations, on the formation mechanism of the stable electret effect is determined. The specific features of the formation of the electret effect in composites based on polyolefins (HDPE, PP), fluorine-containing polymers (F42), and ferroelectric piezoelectric ceramics of the family of lead zirconate–titanate (Pb(Zr,Ti)O3) crystallized under conditions of the effect of electric discharge plasma, are revealed. A physical model of electret composites taking into account the role of homocharges and heterocharges formed in a composite by its dispersion with piezoceramic particles of various structures—rhombohedral, tetragonal, and heterogeneous—is proposed.

Concentration dependences of the surface tension and density of solutions of three-component acetone–ethanol–water systems and the bounding binary systems at 273 K are studied. The molar volume, adsorption, and composition of surface layers are calculated. Experimental data and calculations show that three-component solutions are close to ideal ones. The surface tensions of these solutions are calculated using semi-empirical and theoretical equations. Theoretical equations qualitatively convey the concentration dependence of surface tension. A semi-empirical method based on the Kohler equation allows us to predict the concentration dependence of surface tension within the experimental error.

The concentration dependence of the surface tension of water suspensions of bentonites is studied experimentally. Possible reasons for the emergence of the minima on isotherms of the surface tensions of dispersed systems are analyzed.

Meiotic and mitotic chromosomes have a complex of differences. (1) At the early prophase I of meiosis, chromosomes acquire protein axial elements (AEs) that were absent in mitosis; in addition to somatic cohesins, AEs contain the meiosis-specific cohesins REC8, SMC1β, and STAG3. (2) At the middle prophase I, protein lateral elements (LEs) of synaptonemal complexes (SCs) are formed on the basis of AEs. The LE proteins are not conserved, but in Saccharomyces cerevisiae and Arabidopsis thaliana they contain functional domains with conserved secondary structures. Among the almost 679 thousand proteins of primitive eukaryotes that we studied by bioinformatics methods, in green and brown algae, some lower fungi, and Coelenterata, we revealed proteins or functional domains similar to SC proteins. (3) During the pachytene and diplotene stages of meiosis, chromosomes of spermatocytes and mother pollen cells acquire a general structure resembling the structure of amphibian and avian lampbrush chromosomes in miniature. Lateral chromatin loops with sizes of 90, 160, and even over 480 Kb were observed in human spermatocytes during the diplotene stage. In combination, all these observations confirm the considerable conservation of the scheme of molecular and ultrastructural organization of meiotic chromosomes in a large variety of eukaryotic organisms.

Original data on the temperature dependence of the surface tension of indium, obtained using two independent approaches (a large sessile drop and the maximum pressure in a drop) are presented. The focus is on analyzing possible methodological shortcomings of experimental studies in which the surface tension values of a number of pure metals are obtained that are considerably higher than the results from measuring surface tension by traditional means. It is found that cleaning the investigated metal surfaces through bombardment with heavy ions of inert gases can lead to violations of the thermodynamic equilibrium conditions of a surface with its own saturated vapor, and to the ensuing consequences.

DNA attachment to the lateral elements of the synaptonemal complex (SC) in human spermatocytes was studied by the FISH technique using a commercial probe. The probe is a 160-kbp fragment from the 17p11.2 region containing the RAII gene and D17S620 marker (the probe for the deletion in human chromosome 17 causing Smith-Magenis syndrome). It was found that the DNA probe produced lateral chromatin protrusions in contact with SC stained with antibodies to SYCP3 protein. The morphological configuration of lateral chromatin protrusions depended on the substages of meiotic prophase I. At the zygotene, FISH probe forms two sticks with lengths about 6 μm perpendicular to the SC longitudinal axis, one stick at each SC side. At the early pachytene, each stick transforms into a globule, again one globule at each SC side. At the late pachytene, each globule transforms into two crumbly globules composed of short threads and clumps. At the diplotene, globules finally transform into thin DNA (chromatin) loops up to 10 μm from the base to the top with periodic thickenings (beads) along their length. As a result of this dynamic transformation, two chromatin loops with beads have been formed on each side of the SC of chromosome 17. These loops are most probably the loops of sister chromatides. Thereby, four loops of the full set of four chromatides were observed in the particular site of chromosome 17 bivalent, i.e., representing two pairs of chromatides. Thus, we are the first to have visualized true “open” lateral chromatin loops in human male meiotic prophase I rather than the usually postulated “loops” in reports on condensed road- or brushlike chromatin protrusions attached to the lateral elements of synaptonemal complexes. The open configuration of chromatin loops presumably depends on activation of transcription during the late pachytene-early diplotene. They resemble mini lateral loops of lampbrush chromosomes.

Covalent bonding of polyhexamethyleneguanidine amides of maleic and o-phthalic acids to the aminated silica surface was performed. The complexing properties of the obtained composite adsorbents with respect to Zn(II), Cu(II), Fe(III), Co(II), Pb(II), Ni(II), Mn(II), Mo(VI), and Cr(VI) ions were studied. The Mo(VI) and Cr(VI) reduction was detected on the modified silica surface bearing polyhexamethyleneguanidine amide with o-phthalic acid. The formation of different-ligand complexes with transition metal cations adsorbed on the synthesized composite surface was studied.

Synaptonemal complexes (SCs) are intranuclear structures that facilitate the reversible lateral synapsis of homologous chromosomes in the course of meiosis. It is still unclear which DNA nucleotide sequences are responsible for the attachment of chromatin to SC lateral elements. Considering the features of the dispersed repeated sequences (RSs), it is possible to assume that they participate in the structure and functional organization of the meiotic chromosomes. Using numerical analysis, we have investigated the relationship between the RS and the distribution of meiotic recombination events in mouse chromosome 1. Using in situ hybridization on spread mouse spermatocytes, we have examined the arrangement of different types of RSs relative to SCs. Hybridization signals of B1(Alu), B2, and minisatellite probes were localized predominantly in SCs regions. Based on the results, we proposed a model of meiotic chromosome organization. According to the model, RSs participate in the attachment of chromatin loops to SCs.

The possibility was determined for covalent binding of amide of maleic acid and polyhexamethyleneguanidine to a silica gel surface previously activated with cyanur chloride. Adsorption of Zn(II), Cd(II), Pb(II), Cu(II), Mn(II), Ni(II), Fe(III), and Co(II) cations from aqueous solution with a modified silica obtained was studied. The possibility of subsequent formation on the surface of mixed ligand complexes

Using high-performance catalysts prepared from zeolites Y, M, and ZSM-5, the dependence on the acid and micropore characteristics of modified zeolites was studied for the yields of products of dehydrocycloaromatization of C2+ alkanes, the isomerization of n-pentane, and the disproportionation of toluene. On the basis of the obtained experimental results and published data, it was shown that the initial activation of reactant molecules occurs on acid sites regardless of their acid strength and that the formation and rearrangement of C-C bonds are controlled by the molecular-sieve parameters of a zeolite and can be varied via the modification of the virgin zeolites used to prepare the catalysts.

The thermodynamic parameters of the surface layer of the indium-tin-gallium system were studied experimentally.

Aromatization of light hydrocarbons (propane, butane, propane-propene mixture, and cat-cracker off-gases) on ZnO-zeolite and lanthanide-zeolite catalysts based on zeolite TsVM (SiO2/Al2O3 = 62) and industrial catalyst SGK-1 was studied. It was shown that the modification of catalysts with lanthanides leads to an increase in both the total yield of xylenes and the p-xylene selectivity, a change that is explained by the formation of branched intermediates and steric specifics of their further conversion.

Fluorochrome-labeled oligonucleotides (n = 44) corresponding to mouse genome repetitive sequences were hybridized in situ with pachytene nuclei of mouse spermatocytes. Signals of the repetitive sequences MaLR, MER, and (GT)22 were found to be dispersed through chromatin, and signals of B1 repeats and minisatellites were mostly attached to synaptonemal complexes immunostained with anti-SYCP3 antibodies. These results suggest that B1 repeats and minisatellites are candidates for sequences anchoring chromatin to synaptonemal complexes.

A surface tension isotherm equation for ternary systems was derived based on general thermodynamic expressions with consideration for the concentration dependence of the molar surface area. Within the experimental errors, the equation describes the properties of ternary systems with smooth surface tension isotherms.