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A pressure-driven electrolytic membrane system of drum type is proposed. Solutions may be effectively separated by combining the pressure-driven electrolytic membrane technique with water cooling of the electrode. The drainage channels from the anode and cathode regions are independent. A method is proposed for calculating the strength of the system’s housing. The required thickness of the outer wall and the fiberglass flanges is determined.

We perform X-ray diffractometry, electron-microscopic, and kinetic studies of the surface layers of UAM-50 and UAM-100 ultrafiltration membranes. The crystallinity of the membranes is studied by X-Ray diffraction in the region of large angles 2θ from 2° to 40°, using a DRON-3 diffractometer with modern methods of the computer processing of experimental data. Comparative analysis of the X-ray diffraction patterns reveal the coincidence of the diffraction angles for the working and air-dry samples of ultrafiltration membranes, while the membrane samples have three pronounced maxima located approximately in the angular range from 17.50° to 25.60°. The crystallinity for the air-dry samples is 68% for UAM-50 and 74% for UAM-100, and for the working samples, it is 32 and 41% for UAM-50 and UAM-100, respectively. Investigations of the surface of drainage layers of the UAM-50 and UAM-100 ultrafiltration membranes are carried out by scanning electron microscopy. The thickness of the active layer is 27 nm for the UAM-50 membrane and 15 nm for the UAM-100 membrane. Pores of different sizes are visible on the surface of the active layer of the membrane; the pore sizes range from 2.5 to 40 nm for UAM-50 and from 10 to 40 nm for UAM-100. Kinetic studies of the ultrafiltration membranes confirm that they have an asymmetric pore structure. Small pores in the membrane trap contaminant molecules, while large pores allow the permeate to pass quickly to a more open permeate carrier, that is, a purified solution. The water permeability of the working membrane increases with an increase in the transmembrane pressure due to an increase in the driving force of the process and rearrangement of the crystal structure (a decrease in the size of crystals in the working sample of the membrane) and a decrease in the crystallinity of the membranes.

The influence of the structure of the surface cellulose acetate layer on the transport characteristics of ultrafiltration composite membranes is considered using the methods of IR spectroscopy and of scanning electron microscopy. The amorphous phase of ultrafiltration cellulose acetate composite membranes is formed at a certain stage of the technological cycle of obtaining a composite membrane. IR spectra are presented where the forms of the absorption bands of valence vibrations of hydroxylic groups at ν = 3339.14–3366.2 cm–1 alter the asymmetry parameter from ~1 for an air-dry sample and to 0.79 for a water-saturated one, which allows the assertion of formation of volumetric supermolecular structure of a cellulose acetate layer of an air-dry sample by two types of hydrogen bonds and dipole–dipole interactions of carbonyl groups. The decrease of the asymmetry parameter to 0.79 of the absorption bands of hydroxylic groups and of the intensity of absorption bands of methyl groups by 2.56, 3.3, and 3.8 times in water saturated samples of membranes occurs because of the destruction of supermolecular structure and reorganization of hydrogen bonds between the active groups of cellulose acetate and molecules of water. The data obtained by the method of scanning electron microscopy allow one to note that the surface layer of ultrafiltration membranes has an asymmetric pore structure. The surface layer of a membrane can be divided into two components: a selectively permeable layer with pores of small size and a pore substrate, in which the pores increase in their diameter as they approach the substrate.

This paper presents an analytical overview of the study of the kinetic and physicochemical characteristics of composite membrane films. UAM-100, UAM-150, and MGA-95 composite films have been studied using thermogravimetry in the temperature range from 30 to 300°C. A kinetic analysis of experimental data by the Freeman–Carroll method is carried out. It was found that hydrated water for all the studied semi-permeable films evaporates in the temperature range from ~95 to ~180°C. Comparison of the ratios of the amount of removed water in the film samples correlates with the geometric parameters of the pores. The values of the activation energy and the pre-exponential factor (E = 26.9 kJ/mol and ln(A ≈ 6.3 (min–1)) in the range 0.2 < α < 0.7 of the degree of dehydration indicate the same regularity in the distribution of water molecules in the polymolecular layer for all composite films. The high dehydration values, e.g., for a sample of a composite semipermeable film MGA-95 at the temperature of the maximum on the thermogravimetry curve (Tmax = 169.6°C) indicate that water molecules form hydrogen bonds both with ionogenic groups of cellulose acetate and with each other.

A comparative study of the application of membrane, electromembrane and electrobaromembrane technologies for various industries in the field of wastewater treatment and technological solutions is presented. The principle of classification of membrane separation processes is formulated. The characteristic periods of the solvent transfer stimulation were determined. Based on the experimental data obtained on the permeability of the solvent through the MGA-80P and MGA-95 membranes, empirical dependences are proposed that describe the kinetic characteristics of the dependence from transmembrane pressure and temperature effects.

The article presents the results of a study of mass transfer in the process of electrochemical extraction of iron, magnesium and manganese ions from technological solutions. Mathematical expressions are obtained, and numerical values of empirical coefficients are determined for theoretical calculation of specific outflow, retention coefficient, and average mass transfer coefficients of the electrochemical membrane process of separation of technological solutions. The dependence of concentration polarization on solution flow rate, pressure gradient, and concentration is analyzed.

Experimental data have been obtained, and the characteristics of the moisture content and permeability of cellulose acetate porous materials were analyzed via thermal action. Dynamic thermogravimetric analysis found that the destruction process in an air-dry sample of the membrane begins at 21°C. It is accompanied by a 2% weight loss and an endothermic effect. The destruction ends at 50°C. With a subsequent increase in temperature, the manifestation of endothermic effect continues a temperature of 120–175°C with the maximum rate of mass loss at 146°C. The weight loss ends at about 190°C and is 6.5%. The study of MGA-80 and MGA-95 porous cellulose acetate films at transmembrane pressure upon temperature exposure showed that the permeability and specific output flow to water increase as the temperature rises to 50°C. Analysis of dependences of the specific output flow on temperature revealed that the specific output flow to water increases by ~18% upon an initial temperature rise of 10°C. This is due to structural changes in the cellulose acetate layer. A further increase in temperature by 15°C leads to an increase in permeability by ~10%. These phenomena are associated with the process of structural transformation in the active layer and the polymer substrate of the MGA-95 and MGA-80P membranes, respectively.

The paper presents the structural organization of the surface (selective) layer. The amorphous phase of the cellulose acetate composite membrane is formed at a certain stage of the technological cycle of producing the cellulose acetate membrane. It presents a mass of broken, entangled, and twisted macromolecular chains connected by a network of hydrogen bonds of various strengths. Analysis of the IR spectra, where the shapes of the absorption bands of the valence vibrations of hydroxyl groups at ν = 3339.14–3366.2 cm–1 with the asymmetry coefficient varying from ~1 for a dry sample to 0.79 for a wet sample, suggests that the bulk supramolecular structure of the cellulose acetate layer of the air-dry sample is formed by two types of hydrogen bonds and the dipole–dipole interactions of the carbonyl groups. The interactions of macromolecules in the equatorial plane are formed by a network of hydrogen bonds of the OH…O type with the participation of a single hydroxyl group of the pyranose ring in cellulose acetate. In the axial direction, the supramolecular structure is organized through the hydrogen bonds of the CH…O=C type between the methane and carbonyl groups, as well as possibly the dipole–dipole interactions between the coplanar ordered dipoles of the C=O groups. The coefficient of asymmetry of the absorption bands of hydroxyl groups is reduced to 0.81–0.79 and the intensity of the absorption band of methyl groups is reduced by factors of 2.56, 3.3, and 3.8 in water-saturated samples due to the destruction of the supramolecular structure and the reorganization of the hydrogen bonds between the active groups of cellulose acetate and water molecules. The absence of an absorption band of ν = 873.53–851.9 cm–1 in the water-saturated samples indicates a conformational rearrangement of the macromolecules into a linear form with the formation of narrow mesopores of cellulose acetate between the macromolecules.

Results are presented from investigating active and drainage layers of composite films (membranes) UPM-50 and UPM-100 before and after exposure to transmembrane pressure by means of IR spectra of reflection, X-ray scattering, and raster electron microscopy. It is found that changes in the IR spectrum of the working sample are caused by the destruction of weak bonds of C=O···H–N amide fragments of the polysulfonamide film. A drop in (C=O) vibration frequency ν by Δν = 20 cm−1 indicates redistribution of the electron density between C=O-groups and benzene rings as a result of the inductive effect of coupling, which results in the formation of charged functional groups CO−. The presence of CO– groups fragments a new supramolecular structure whose stability due to the dipole–dipole interaction of carbonyl anions. X-ray scattering of the initial and working samples in the 10°–35° range of angles 2θ is determined by three intense reflections at angles 2θ ~ 17.23°, 22.24°, 25.41° from crystallographic planes ((010), (100), and (110)) corresponding to the crystalline structure of lavsan (polyethylene terephthalate). A comparative analysis of the reduced intensities of reflections from crystallographic planes (010), (100) and the sizes of lamellas indicates that transmembrane pressure initiates conformational rearrangement of crystallites with crystallographic axis b oriented parallel to the film plane.

To clarify the organizing effect of Semax and HLDF-6 peptides on the kinetics of protein synthesis in hepatocytes, in addition to an in vitro study (Brodsky et al., 2019), the effects of these peptides in vivo have been studied. The circahoralian (ultradian) rhythm of protein synthesis, that is, a marker of the direct cell-to-cell communication, was investigated in rats of different ages. Peptides were injected intraperitoneally into young (2–3-month-old) or old (1.5–2-year-old) rats at a 50–100-µg/kg dose. Hepatocytes were isolated and sparse or dense cultures were established. In sparse cultures from young rats that received one or another peptide, the rhythm of protein synthesis was observed; in the cultures from rats of the same age that were injected with saline, no rhythm was found. In dense cultures of old rats after the action of the peptide, the amplitudes of the rhythm of protein synthesis did not differ from the rhythms observed in young rats; after saline injection, the rhythm amplitudes were twice as low. Injection of the peptide into adult rats that had previously received dopamine caused a protein synthesis rhythm characteristic for rats of this age; the administration of dopamine abolished the rhythm. The synchronizing effect of the peptides was maintained for at least 2 days after their single administration to the rat. The use of Semax or HLDF-6 is recommended to compensate for the disturbances of the kinetics of protein synthesis in humans in aging and pathology.

We studied the effect of bovine brain gangliosides, individual ganglioside GM1, and melatonin on the rate of wound closure under in vitro conditions and the effect of melatonin on the rate of wound healing under in vivo conditions. It was shown that bovine brain gangliosides and melatonin reliably increased cell migration in the experimental wound model. This effect was detected when the cell cultures were treated with the test preparations after wound infliction and when the cultures of human keratinocytes were pretreated before wounding. Analysis of the effect of melatonin on the rate of wound healing in vivo showed that melatonin accelerated this process, especially at the middle stages corresponding to the proliferation phase (days 3-6 after surgery). Histological analysis revealed intensification of epidermal cell proliferation at the edges of the wound starting from day 4 after surgery.

The effect of temperature on the conformation changes of the structural and the thermophysical characteristics in the UAM-50, UAM-100, and MGA-95 composite films of cellulose acetate are studied. An interphase layer appears at the phase interface in the UAM-50 and the UAM-100 samples according to the data of differential scanning calorimetry. An exothermic effect appears in the calorimetry data curves for water-saturated samples in the temperature range of ΔT = 125–226°C with ΔH = 20.7 kJ/kg for the UAM-50 and 27.95 kJ/kg for the UAM-100; this indicates hydration of the polar groups of cellulose acetate and polyamide in the interphase layer of the composite films. When composite films in the air-dried and the water-saturated samples were studied with differential scanning, there was a redistribution of the ratio between the quantities of perfect crystalline structures in crystallites with different melting enthalpies. The melting enthalpy decreases from 6.06 to 0.99 kJ/kg for the MGA-95 low-temperature phase, from 1.99 to 1.72 kJ/kg for the high-temperature phase; from 3.04 to 1.38 kJ/kg for the UAM-50 low-temperature phase, from 8.12 to 1.76 kJ/kg for the high-temperature phase; from 4.99 to 1.5 kJ/kg for the UAM-100 low-temperature phase, and from 2.33 to 0.77 kJ/kg for the high-temperature phase. The total melting enthalpy of the endothermic peaks also decreases for all three samples; this is an indication of decreased crystallinity in the water-saturated samples of the composite films.

In the search for stable factors regulating direct cell–cell interactions and effects on the properties of cells in aging organisms, the regulatory peptides Semax and HLDF-6 were studied. The circahoralian rhythm of protein synthesis in cells in vitro served as a marker of cell–cell interactions. The peptides normalized the cell–cell interactions, which are greatly weakened during aging. It is shown that the peptides organize the protein-synthesis rhythm in primary rat hepatocyte cultures. The effect of the HLDF-6 peptide was realized via metabotropic glutamate receptors; the blockade of these receptors by the antagonist MCPG abolished the effect of the peptide. The protein kinase inhibitor H7 prevented the effect of the peptides on the protein-synthesis kinetics. Just as for other signaling factors, the activation of protein kinases in the case of the peptides regulates the key process of direct cell–cell interactions. The effect of a single signal of each of the peptides was retained for at least 1 day. Our data allow the peptides to be recommended for improving elderly people’s condition and block the factors that disorganize the protein-synthesis kinetics.

A flat-chamber electrobaromembrane apparatus with improved design and technological characteristics for wastewater treatment and differentiated ion extraction from industrial water systems was developed. A method allowing the total working area of the anodic and cathodic membranes, the sizes of the anodic and cathodic outlet flows, and other parameters of the membrane process to be calculated was presented. The design and technological parameters of the chamber and electrobaromembrane apparatus as a whole were calculated.

The pore space structure of MGA-95 and ESPA membranes has been investigated by the smallangle X-ray scattering (SAXS). The pore radii as the parameters forming the skeleton of the pore space of the reverse-osmosis composite membranes have been established. Three types of scattering pores (sphere, disc, and cylinder) are found in the region of the X-ray scattering vector of 0.171 < s < 0.538 nm−1, and their average radii of gyration have been determined. The pore structure of the MGA-95 and ESPA membranes, which can be described in terms of the self-affine fractal concept, has been revealed. In the region of the scattering vector of 0.245 < s < 0.342 nm−1 (the average pores with 9.2 < r

The kinetics of protein synthesis was investigated in primary cultures of hepatocytes from old rats in serum-free medium. The rats were fed mixed fodder supplemented with glutamic acid and then transferred to a regular mixed fodder. The amplitude of protein synthesis rhythm in hepatocytes isolated from these rats increased on average 2-fold in comparison with the rats not receiving glutamic acid supplement. Based on this indicator reflecting the degree of cell-cell interactions, the cells from old rats were not different from those of young rats. The effect was preserved for 3-4 days. These results are discussed in connection with our previous data on preservation of the effect of single administration of gangliosides, noradrenaline, serotonin, and other synchronizers on various cell populations. In contrast to the other investigated factors, glutamic acid is capable of penetrating the blood-brain barrier, which makes its effect possible not only in the case of hepatocytes and other non-brain cells, but also in neurons.

The state of water in the MGA-95 composite cellulose acetate membrane has been investigated using the techniques of IR spectroscopy and thermogravimetry. It has been concluded that water, acting a plasticizer, structures macromolecules of the amorphous phase of the cellulose acetate membrane and promotes its transition to a liquid crystal phase forming additional capillary spaces.

Dense cultures of hepatocytes from old rats (~2 years old, body weight 530-610 g) are different from similar cultures of hepatocytes from young rats by the low amplitude of protein synthesis rhythm. Addition of glutamic acid (0.2, 0.4, or 0.6 mg/ml) into the culture medium with hepatocytes of old rats resulted in increase in the oscillation amplitudes of the protein synthesis rhythm to the level of young rats. A similar action of glutamic acid on the protein synthesis kinetics was observed in vivo after feeding old rats with glutamic acid. Inhibition of metabotropic receptors of glutamic acid with α-methyl-4-carboxyphenylglycine (0.01 mg/ml) abolished the effect of glutamic acid. The amplitude of oscillation of the protein synthesis rhythm in a cell population characterizes synchronization of individual oscillations caused by direct cell-cell communications. Hence, glutamic acid, acting as a receptor-dependent transmitter, enhanced direct cell-cell communications of hepatocytes that were decreased with aging. As differentiated from other known membrane signaling factors (gangliosides, norepinephrine, serotonin, dopamine), glutamic acid can penetrate into the brain and thus influence the communications and protein synthesis kinetics that are disturbed with aging not only in hepatocytes, but also in neurons.

The paper presents experimental study of physical water condition and mass transfer in cellulose acetate and dynamic semipermeable membranes by infrared spectrometric and hydrodynamic methods. The authors found that OH-groups of cellulose acetate form a nonequilibrium grid of hydrogen bonds between molecules and their fragments in the amorphous phase of the semipermeable membrane in the air-dried sample. The water molecules adsorbed on active —OH and —C = O groups, particularly in the amorphous phase, create additional negative charge on the molecules of cellulose acetate resulting from the orientation of the water dipoles, which leads to electrostatic repulsion of broken, stranded molecule fragments and straightening of polymer molecule while breaking intermolecular hydrogen bonds. Thermogravimetric studies to find out the structural organization of hydrogen bonds and water condition in the samples of the semipermeable polymeric MGA-95 membrane showed that at temperatures in the air-dry and water-saturated samples the membrane degradation process starts and ends with mass loss and endothermic effect. The research proves the fact of dynamic membranes formation on the ultrafilters from water starch solutions. Due to the changes in condition and volume of water in the dynamic layer of the membrane, it is possible to change kinetic coefficients, i.e. to regulate the process of baromembrane separation of industrial water solutions. Electro-kinetic characteristics of reverse osmosis semipermeable membranes were studied. The experimental curves of the potential depending on sorption of sodium bicarbonate by MGA-95 and LSA-100 membranes were obtained. The discrepancy between the calculated and experimental data did not exceed 10 %. The method devised for determining the membrane potential in the process of sorption of sodium bicarbonate can be used as a testing methodology of polymeric semipermeable membranes.