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This work is devoted to the preparation of microfiltration ceramic tubular membranes based on α-Al2O3 with deposited catalytically active layers for use in wastewater treatment processes. Cobalt and manganese oxides were used as the material of the catalytically active layer; deposition was carried out using a mixture of aggregative stable aqueous dispersions of Co3O4 and MnO2 nanoparticles. According to the data of scanning electron microscopy, the thickness of the obtained deposited layers does not exceed 3 μm. X-ray fluorescence analysis confirmed the presence of Mn and Co on the surface of the samples. The resulting membranes with a mass of 10 mg of the deposited layer of the oxide mixture were tested in the methylene blue decomposition reaction in dilute aqueous solutions (1,2 mg/L). The reaction was carried out in a batch reactor at room temperature, complete discoloration of the solution was observed after 180-240 minutes.

The paper deals with the issues of natural water purification from iron compounds. A comparison of polymeric and ceramic membranes is given. During the experiments, ceramic membranes modified with titanium and completed in a filtering element were used. Experiments on filtration of simulated solutions of ferric iron have been carried out. The dependence of the permeate flux on time for various initial concentrations of ferric iron and the dependence of the working pressure on the volume of the filtrate for various initial concentrations of ferric iron, at a constant filtration rate is shown. It was found that the residual concentrations of iron (III) compounds, regardless of the experimental conditions, met the regulatory requirements and did not exceed 0.3 mg/l. Based on the results obtained, flow diagrams of ultrafiltration units based on ceramic membranes were proposed.

The possibility of preparing and properties (surface morphology, microhardness, corrosion resistance) of nickel–zirconia composite coatings electrodeposited from nickel acetate solutions containing a dispersed phase in the form of a conventional polydisperse crystalline micropowder and a sol with nanoscale particles have been discussed. The effect of the particle size and concentration and the electrolysis conditions on the properties of the coatings has been determined.

Aspects of a technology for producing tubular corundum-based substrates for membranes are examined. The ratios of the components and the rheological properties of slip are determined. Experiments on the deposition of a selective layer on a substrate are performed. The composition and technology developed for fabricating blanks make it possible to create substrates with open channel porosity of the order of 42%, pore size no more than 1 μm, and ultimate strength in bending 20 MPa.

Flat membrane contactors comprising ceramic disk microfiltration membranes with a deposited layer of Co3O4 are obtained. The characteristics, such as the thickness of the layer and the pore-size distribution, are determined and the specific surface of the substrate and the deposited layer of Co3O4 are determined. It is shown that the membrane contactors obtained are suitable for liquid-phase catalytic oxidation of phenols under soft conditions, including in waste waters.

A procedure is developed for the synthesis of hydrosols of oxygen-containing cobalt compounds. The hydrosols are stable to aggregation for several weeks in the absence of additional stabilizers. It is established that the synthesized hydrosols contain crystalline particles formed from a mixture of CoO(OH) and Co3O4. According to transmission electron microscopy data, the most probable diameter of the particles is about 30 nm. The hydrosols are stable to aggregation at pH 6.2–8.0. In this pH range, the particles are positively charged and the values of their electrokinetic potential are no higher than 10 mV.

The effect of the synthesis conditions of aqueous dispersions of oxygen-containing lanthanum compounds on the size, shape, and phase composition of nanoparticles is studied. It is established that the hydrolysis of lanthanum nitrate at the boiling point of a solution affords sols with a narrower particle size distribution and a higher degree of particle crystallinity. The ranges of [OH−]/[La3+] concentration ratios are determined within which aggregatively stable aqueous dispersions of oxygen-containing lanthanum compounds can be synthesized.

A procedure is developed for the synthesis of copper(II) oxide hydrosols. It is shown that the main parameters that govern the reproducibility of the synthesis results and the aggregation stability of synthesized hydrosols are the temperature of copper(II) nitrate hydrolysis and the concentration of a peptizing agent. Dispersed phase particles are shown to have a cylindrical shape with a prevailing length-to-diameter ratio of approximately 2.7.

It is shown that cerium dioxide hydrosols can be stabilized by polycationic compounds of zirconium, and the optimum conditions of the stabilization are determined. Stable CeO2 hydrosols with concentrations of higher than 20 wt % are prepared; the sizes and electrophoretic mobility of their particles, as well as sol stability in the presence of some electrolytes, are investigated. The nature of the aggregation stability of the stabilized cerium dioxide sols is discussed.

The formation of aggregatively stable copper dispersions by the reduction of copper salts with thiourea dioxide or sodium hydroxymethane sulfinate in a water-organic solvent is studied. X-ray electron spectroscopy and photon correlation spectroscopy showed that the chemically formed copper exists as nano-sized particles.

The phenomenon of association of transcribed genes into so-called transcription factories and also the role of these associations in spatial organization of the eukaryotic genome are actively discussed in the modern literature. Some authors think that the association of transcribed genes into transcription factories constitutes a major factor supporting the function-dependent three-dimensional organization of the interphase genome. In spite of the obvious interest in the prob- lem of spatial organization of transcription in the eukaryotic cell nucleus, the number of experimental studies of transcrip- tional factories remains rather limited and the results of these studies are often contradictory. In the current review we have tried to critically re-evaluate the published experimental results that constitute the basis for current models and also the models themselves. We have especially analyzed the existing contradictions and attempted to explain them whenever possi- ble. We also discuss new models that can explain the biological significance of clustering of transcribed genes and show pos- sible mechanisms of the origin of transcription factories in the course of evolution.

It is shown that silver metal nanodispersions can be produced through the silver mirror reaction using the Tollens reagent in Aerosol OT-stabilized water-in-oil microemulsions using glucose as a reducing agent. The ranges of the formation of microemulsions and their droplet sizes, as well as component ratios and reaction conditions that yield stable nanodispersions, are determined.

We have studied how the conditions in which the nuclear matrix is isolated influence the association of transcribing DNA with the nuclear matrix. Extraction of nuclease-treated nuclei with a low ionic strength solution before a high salt nuclei with a low ionic strength solution before a high salt extraction completely abolishes this association. However, RNA removal by RNAase treatment does not affect the binding of transcribing DNA to the nuclear matrix. The nature of the association of active genes with the nuclear matrix is discussed.

Several preparations of nuclear matrices containing varying amounts of DNA were obtained from mouse plasmocytoma P3-X63-Ag8.653 cells and tested for the presence of RNA polymerase II activity. It has been demonstrated that about 25% of RNA polymerase II activity detected in the original nuclei can be recovered in isolated nuclear matrices. Only DNA-bound RNA polymerase II was found in the isolated matrices, while both free and DNA-bound RNA polymerase II activities were detected in the original nuclei. RNA polymerase II activity found in the isolated matrices did not depend on the portion of DNA recovered in the nuclear matrices in a large interval between 91 and 1.5% of DNA content in the original nuclei. The conclusion has been drawn that initiated RNA polymerase II molecules are non-randomly distributed along DNA loops. They are concentrated near the points of DNA attachment to the nuclear skeleton.

The synthesis of hydrosols of copper(II) basic salts by the hydrolysis of copper(II) nitrate in the presence of ammonia was developed. A pH range and an optimal molar ratio [Cu2+] : [OH–] = 1.1 : 1.0, at which hydrosols stable with respect to sedimentation were formed, were determined. The average hydrodynamic radius of dispersed phase particles ranging from 220 to 280 nm was measured by the photon correlation spectroscopy. It was shown that the hydrosols can be stabilized by poly(vinyl alcohol), and its optimal concentration providing their aggregation stability was determined. The thresholds of fast coagulation of the initial and stabilized hydrosols in the presence of potassium chloride and ammonium sulfate were found.