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Numerical modeling for the purpose of receiving the temperature field of cooled rotor blades and its improvement is an integral process of modern design of gas turbine engines since the issue of cooling at gas temperature at the combustion chamber outlet over 1800-2000 K is becoming one of the key ones. To ensure the specified parameters of turbine operation during its design, it is necessary to obtain reliable calculation data. The article presents an algorithm for forming a calculation model to determine the thermal state of the working blade of a high-temperature high-pressure gas turbine in the Ansys program. The process of preparation of geometric and grid models is described, the boundary conditions used to set up the project in Ansys CFX Pre are given. A method for determining the cooling efficiency factor using Ansys CFX Post is also presented. The distributions of the temperature field and the coefficient of cooling efficiency over the surfaces of the blade to be cooled are obtained. Integral values of the coefficient of cooling efficiency for the designed blade at various cooling air flow rates were compared with statistical data. On the basis of the comparison a conclusion was made that the working blade considered in the work corresponds to the modern level of cooling efficiency.

A new method of electroprometry has been proposed that allows continuous investigation of extended sections of a hollow fiber membrane. Samples of polysulfone hollow fiber membranes with different porous structures were obtained: finger-shaped and spongy. These membranes were examined on a laboratory electroprometric apparatus with continuous scanning along the length of the hollow fiber membrane sample at a high voltage of 15 kV. Defects were detected in these hollow fiber membranes by the proposed method of electroporometry, the nature of which was then investigated using scanning electron microscopy. A correlation was found between the size of the detected defect and the magnitude of the corona discharge current signal: the larger the defect, the greater the absolute value of the current. It is shown that the proposed method can be effectively used as an express method to study the homogeneity of the porous structure of hollow fiber membranes in extended areas with geometrical localization of possible defects.

The article presents the results of the development of proposals to increase the safety margin of the blades and the efficiency of a single-stage axial flow turbine compressor of a small-sized turbo-shaft engine being modernized with the use of multidiscipline optimization methods. Analysis of the initial version of the turbine showed that the margin of safety of the working blades is significantly lower than that required by the strength standards. To eliminate the problem encountered the task of blade development was initially solved only according to strength characteristics, without taking into account gas dynamic processes. As a result, the geometry of the working blades that met the strength requirements was obtained. It was used as a starting point for solving the joint task of optimizing the blading, taking into account gas dynamic and deformation processes. As a result of joint optimization, a turbine version meeting the strength standards was obtained, although we had to slightly reduce the efficiency of the turbine by 0,2%.

Background: At present, the diagnosis of lymphoproliferative disorders is based on the combination of blood or bone marrow smear morphology and immunophenotyping by flow cytometry. Immunophenotypic testing by flow cytometry technique is available only in big medical centers, which is not always convenient for a patient. Therefore, development of an available method for preliminary diagnosis of lymphoproliferative diseases not requiring special equipment seems relevant.Materials and methods: Peripheral blood mononuclear cells from 17 patients admitted to the hospital with suspicion of a lymphoproliferative disorder, and 17 healthy donors were studied on a cell biochip for determination of proportions of cells positive for various surface CD antigens. The diagnosis was verified by flow cytometry.Results: Compared to healthy controls and patients with T-cell lymphoproliferative disorders (TCLPD), the patients with B-cell lymphoproliferative disorders (BCLPD) had significantly lower proportion of CD7+ cells (medians, 7% and 73% respectively, p=2×10-6 for comparison with healthy controls; median 7% and 93% for comparison with TCLPD, p=0.032). In addition, the patients with BCLPD had higher proportion of peripheral СD19+ mononuclear cells, compared to that in the patients with TCLPD and healthy donors (medians 84% and 13% for comparison between BCLPD and healthy control, p=2×10-5; 84% and 3% for comparison of BCLPD and TCLPD, p=0.033). The patients with B-cell chronic lymphocytic leukemia had significantly higher CD5+ cells in the cell biochip compared to the patients with other BCLPD (medians 72% and 9%, p=0.024). The patients with TCLPD had significantly lower proportion of CD19+ cells than the healthy controls (medians, 3% and 13%, respectively, р=0.042).Conclusion: The study has demonstrated the potential to use the previously developed cell biochip for diagnosis of lymphoproliferative diseases. The biochip makes it possible to sort out white blood cells according to their surface differentiation antigen for their further morphological analysis. The cell biochip allows for the differential diagnosis between BCLPD and TCLPD and determination the lymphocyte clones based on the expression of immunoglobulin light chains.

The most important information for the practical use of flexible-chain polymers is the change in structure in the presence of external influences. A conformational model for calculating the mean square of the dipole moment of a macromolecule is constructed in this work, provided that there is no correlation between the conformations of monomer units in a heterogeneous temperature field.

The design and dimensional characteristics of the spinneret affect not only the geometry of the hollow fiber, but also the transport properties of the hollow fiber membranes. In the literature available today, there is a limited number of works in which the influence of the design and dimensional characteristics of the spinneret is studied. In this work, using the example of polysulfone hollow fiber membranes, it was shown that the use of a spinneret with smaller annular diameters leads to an increase in the gas permeability of the hollow fiber membrane with a decrease in the value of the ideal selectivity for the He/CO2 gas pair. It was found that using the spinneret with large annular diameters, the hollow fiber membrane is obtained with a smaller value of the average pore size of the flow, which is in agreement with the obtained data on gas permeability.

An important practical and fundamental problem in the production of porous polymer membranes is the study of the porous structure and the detection of "defects" or large pores in the area of ​​the membrane. Known porosimetry methods cannot solve this problem. This work proposes a new non-destructive express method for studying the porous structure of asymmetric polymer membranes in high-intensity electric fields. This method can be successfully implemented on both flat sheet and hollow fiber membranes with a known porous structure. On the example of hollow fiber membranes made of polyacrylonitrile and polysulfone an assessment of the chemical structure effect of the membrane material on the high-voltage discharge currents in a highly inhomogeneous electric field through hollow fiber membranes with a given pore size was made. Under normal conditions and an average intensity of an inhomogeneous electric field E = 5 kV/cm, the results obtained allow us to conclude about a certain practical potential of the developed express method.

In the article, within the framework of the conformational approach, the problem of averaging the square of vector quantities of complex polymers is presented. This approach is based on determining the average values of the square of the dipole moment for the µ-th monomeric unit of the chain, which is a unique parameter of the supramolecular structure of the polymer, depending on the product of the rotation matrices. A generalization of the matrix method of averaging the product of several tensor quantities over possible conformations within the entire macromolecule is considered.

In the work, the methods of formalized modeling assessed the profitability of a possible Internet resource. The model makes it possible to carry out by public means (using spreadsheets) a comprehensive analysis of profits, taking into account possible competitors and their production volumes, demand for products, and to form a plan for the sale of products. The model clearly demonstrates the possibilities of a systematic approach in solving problems of financing Internet resources.

The paper analyzes the change in the entropy production of an open thermodynamic forest ecosystem, in which processes associated with the entry of a negative entropy flow into it can be realized. Using the example of computer modeling of the dynamics of effective specific entropy production for a single-pedigree stand, it is shown for the first time that the specific entropy production as a function of time corresponds to the Prigogine-Glensdorf principle, and the time to reach a stationary state coincides with experimental values from forestry tables.

The paper considers the "observer effect" on the example of an analysis of the results of an experiment to determine the power of emission bands by hydrogen, helium and argon atoms by different experimenters using the same equipment. To obtain atomic spectra, a gas discharge tube and a universal UM-2 monochromator have used. The results of the work performed showed that, in accordance with the chosen estimation technique, the magnitude of the radiation power is largely determined by the accuracy of measuring the bandwidth, which varies greatly among observers.

In Lake Amut (the Verkhnyaya Angara drainage basin) the third population of Arctic charr Salvelinus alpinus (L.) in Baikal basin was found, a presumed invader from the Lena basin; besides, one more representative of Lena ichthyofauna was recorded—sculpin Cottus cf. poecilopus Heckel. This lake is situated close to the divide with the Pravaya Mama River (the Vitim basin), not far from its main channel. The relief structure of the watershed area, in which Lake Amut is located, indicates high probability of the invasion of Lena species into Baikal basin at this place. Data on morphology, age, growth and diet of Arctic charr from Lake Amut are presented and compared with the data on other charr from Baikal basin. New records are discussed in the context of Pleistocene paleogeography of the Baikal region relevant to the history of its fish fauna formation.

The analysis of the current practice of financial monitoring in Russia is given. A study of the main directions, methods and forms of its implementation in the budgetary sphere and commercial organizations was carried out. The procedure for its implementation, participants, methods and techniques of verification are considered. On the basis of the comparison, common features and differences of external financial monitoring in commercial organizations and the budgetary sphere were identified, conclusions were formulated.

The draw ratio (DR) is an important parameter in the process of spinning hollow fiber membranes, by which their separation and performance characteristics can be controlled over a wide range of values. For the first time, a method for determining the DR using a roller movable in the vertical direction is described, which makes it possible to establish the ratio of the dope extrusion linear flow rate to the take-up speed. In the course of the work, polysulfone hollow-fiber membranes were obtained at various DR values. The influence of the draw ratio on the morphology and geometric and gas transport properties of the resulting polysulfone hollow fiber membranes has been examined.

The spinning solution properties (viscosity, chemical composition) can be varied depending on the method of its preparation. These variations might cause changes in the thermodynamics and kinetics of the phase separation process during the membrane formation. In this work, the influence of various modes of spinning solution preparation on the morphology, geometric and gas transport properties of the resulting polysulfone (PSf) hollow fiber membranes was investigated. The differences in methods of solution preparation were the temperature and time of stirring. It was found that with the transition to the lower-temperature stirring of the spinning solution the outer diameter and wall thickness of the fiber increase, and the thickness of the selective layer decreases. The highest ideal selectivity values are observed with the solution stirring for 5 hours at temperature 120 °С (3.1 for pair He/CO2). The maximum values of the gas permeability are achieved in the mode of the solution stirring for 24 hours at temperature 50 °C (P/l (He) = 201 m3/( m2∙h∙atm); P/l (CO2) = 83 m3/( m2∙h∙atm)).

The article discusses the concept of “regulatory guillotine” and how its realization in the Russian Federation will affect on the field of assurance of measurement uniformity. According to the principles of the “guillotine”, regulatory requirements that negatively affect the existence and development of entrepreneurial activity should be identified and either completely eliminated or maximally simplified. The Government of the Russian Federation has developed an action plan (“roadmap”) for the realization of the “regulatory guillotine” mechanism, according to which all obsolete regulations will be repealed or no longer valid in the territory of the Russian Federation, and new ones will be developed in their place, corresponding to actual trends and realities . In addition, new systems of legal regulation will be built in the relevant areas of activity, based on the principles of openness, scientific and technical soundness, risk-based orientation, proportionality and feasibility. Since field of assurance of measurement uniformity is inextricably linked with most fields: from production and labor productivity, to ensuring defense capabilities and national security, any reforms will affect on the country's social and economic development.

This article deals with the initial data coming from the Ivolga Fortress archaeological site located in the Trans-Baikal area. Multidisciplinary investigations were performed, including palynological and archaeozoological studies. Palynological data reflects the palaeovegetation of the region and shows the abundance of forested landscapes in the past. The fauna was made of molluscs (7 taxa), fishes (14 taxa), amphibians (3 taxa), reptiles (1 taxon), and wild mammals (18 taxa). The species composition and environmental data show the mosaic character of landscapes surrounding the ancient settlement: taiga and forest, steppe and forest-steppe biotopes, as well as meadows in the Selenga valley with the prevalence of open steppe spaces. In the era of the Xiongnu Empire 209 BC – 48 AD (Kradin, 2001) the climate was less arid than it is now.

The influence of parameters of the dry-jet wet spinning process was studied on properties of porous polysulfone hollow fiber membranes. The air gap distance, the dope extrusion pressure, bore fluid pressure and temperature were chosen as the studied parameters. Their effect on the geometric and morphological properties of membranes was investigated. The optimal parameters were revealed for the formation of polysulfone hollow fiber membranes, promising for use as porous supports of composite membranes. High gas permeability were achieved with pore sizes providing the Knudsen flow regime: carbon dioxide permeability P/l(CO2) = 48.3 m3 m–2 h–1 atm–1, and values of ideal selectivity α = 2.63 and 0.87 for He/CO2 and CO2/N2 gas pairs, respectively.

The paper considers the option to reduce power consumption in the operation of the underloaded trunk pipeline by engaging additional pump units with lower rotor r.p.m. control using variable frequency drive. Under these conditions, the operating point of the pumps (delivery rate, head) approaches to the rated output, thus increasing the efficiency of the pumps and decreasing the electricity power consumption for pumping operations. The paper presents comparative calculations of operating conditions for a section of the trunk pipeline with a specified pumping capacity of 35 million t/year (60 % of the design load) when one, two and three main line pumps with variable frequency drives are engaged. The power consumption for pumping is calculated using the dependence of the variable frequency drive and motor efficiencies on the electric motor load and rotational speed. Based on the results of calculations, the electric energy saving is determined when additional pumping units are engaged. The experience has shown that when the second main line pump was engaged, the electric energy saving for pumping was 3.7% compared to the condition with one pump running. However, if the third pump is engaged, the saving is only 1.9 % – the decrease is due to lower motor and variable frequency drive efficiencies in the underloaded condition.

The purpose of this study was a historiographic analysis of scientific works on the history of zemstvos of the Middle Volga region, which contained assessments of the organization and activities of zemstvos of the provinces of the Middle Volga region, which, along with city councils, performed the functions of local governments in the second half of the XIX and early XX centuries. The focus is on regional studies. To reveal this topic, the authors set the following tasks: 1) to distinguish periods of historiography; 2) to find out the reasons for the insufficient attention of historians to the Zemstvo in Russian and Soviet historiography; 3) to show the most studied topics and problems raised in the research of Soviet and post-Soviet, as well as foreign historians in the field of Russian local government (including Samara); 4) to characterize the approaches of modern historiography of the Samara zemstvo; 5) to determine the objectives of future research. When studying the conceptual representations of scientists, the methods of historiographic analysis were used, including comparative-historical, chronological, and also the method of periodization. In the historiography of the problem, two periods are distinguished: Soviet and modern. Historiographic facts were used as a source base: the works of Soviet, Russian and foreign historians monographs, scientific articles, scientific reviews and critical reviews, which contain valuable information about the ideas of scientists on Zemstvos, depending on the socio-political situation in the country and the degree of development of the topic under study. The authors found that until the 60-ies of the XX century the history of zemstvos did not cause much interest, and assessments of their activities were in line with the Marxist-Leninist ideology; 19902000-ies the most active and fruitful period of research on the history of the zemstvo. In the 10 of the XXI century enthusiasm for this problem began to decline. After 2010, against the background of the process of integrating local self-government in the state vertical of power that is gaining momentum in Russia and reducing its political significance, the development of history of local self-government and the zemstvo direction in research have lost their popularity, although there are still unaffected aspects and the need to create generalized works has remained, so as a problem of the place of the self-government system in Russia the past, the present and the future has been and remains relevant for our country. The authors also attempted to identify a new vector of problems on the history of the Zemstvo movement in the Russian Empire.

Production of steel rolled products by using traditional metallurgical technologies are rather material- and energyintensive and its concentration at gigantic steel plants resulted in the increased expenses for transportation of raw materials and finished products. To solve the problems, a practice of comparatively small metallurgical plants (mini-mills) construction is becoming widespread in the world steel industry. The mini-mills include modern electric arc furnaces, ladle steel treatment facilities and steel continuous casters combined with continuous rolling mills. The review complied from materials of international conferences, taken place in 2015–2019. In the review achievements in equipment and technology of metal products at mini-mills development considered, as well as analysis of modern economical methods of steel coils presented. It was shown, that the methods of strips endless rolling, widely used already at industrial scale in several countries, enable producing rather thin hot-rolled strips from liquid steel. Universal casting-rolling aggregates (CRA) developed, by which high quality strips of rather wide assortment can be produced. For a mass production of rather thin (down to 0.8 mm) hot-rolled strips, which can in many applications substitute more expensive coldrolled ones, compact aggregates of endless casting-rolling are recommended, which provide the yield of up to 98%. Concepts of the CRA elaborated for production of steel strips of wide assortment, from ultrathin strips to thick (25 mm) ones. The concepts include application of thermomechanical treatment to increase the mechanical properties of the rolled products from various steels, including low-alloyed ones.

In this Letter, we studied the photoresponse in multilayer graphene on a lithium niobate (LiNbO3) crystal under the conditions of an electric potential applied to graphene and transmission of a surface acoustic wave. The acoustoelectric current in graphene when irradiated with light is shown to either increase or decrease depending on the polarity of the potential applied to graphene. A surface acoustic wave causes the appearance of a periodic charge lattice in graphene that enhances the interaction with incident light, which leads to an increase in the photoresponse.

For W2-3 incisional hernias of the midline, a component separation is often needed to achieve closure of the fascia during repair with a mesh. Posterior component separation has been initially performed via open surgical approach, but more recently interest in minimally invasive reconstruction has grown. The aim of this work is to describe the technical aspects of endoscopic hernia repair with posterior component separation and to assess its feasibility in midline incisional hernias, based on the analysis of the results.We prospectively evaluated and analyzed patients with midline incisional hernias who underwent endoscopic posterior component separation by transversus abdominis release (TAR).A group of 100 patients was operated between April 2017 and September 2021. The median follow-up was 27 ± 13.5 months, mean age 59 ± 10.2 years, ASA 2.5 ± 0.7; 94% of patients had comorbidity. There were 7 (7%) complications observed in the early postoperative period-retromuscular hematoma (1), infection of the retromuscular space (4), and thrombophlebitis of superficial veins (2). In 4 (4%) patients, late complications were observed-persistent seroma (3) and chronic pain (1). There were no hernia recurrences in the follow-up period.The use of TAR endoscopic separation can reduce the number of unfavorable surgical site events, compared to the published data on a similar open surgery, while maintaining a low recurrence rate.

The paper presents the problem of averaging the squared vector quantities of complex polymers, based on the determination of the average values of the dipole moment squared for the μ-th monomer unit of the chain and the subsequent averaging over possible conformations within the whole macromolecule within the framework of the conformational approach.

Results are presented from experimental studies of the change in the polarization of polydimethylsiloxane upon adding 0.5% methyl and vinyl groups (grade СKТВ-1 synthetic rubber) according to currents of polarization measured upon crystallization in an inhomogeneous temperature field. A ratio that includes the polarization of flexible polymers and parameters of crystallization in an inhomogeneous temperature field is proposed, based on an analysis of experimental results.

For the first time for the Baikal Lake basin, evidence of the existence of populations of sculpin Cottus cf. poecilopus Heckel (alpine bullhead) characteristic of the adjacent Lena River basin in large northern Baikal tributaries, the Verkhnaya (Upper) Angara and the Kichera is provided. In June 2009 during the study of the lower reaches of the Kholodnaya River (Kichera-Baikal system), 8 individuals of sculpin aged from 3 to 5 years and in August 2009 5 more specimens aged from 4 to 6 were caught. All fish were fertile with the gonads in maturity stage III. In August 2010 33 individuals aged from 4 to 6 were collected in the main channel of the Upper Angara near Novy Uoyan settl.. At about the same time C.poecilopus was registered in stomachs of Arctic charr from Lake Amut (Churo-Upper Angara-Baikal system) near the divide with the Pravaya (Right) Mama (Mama-Vitim-Lena system). In August 2010 17 specimens aged from 1 to 4 were caught in the Upper Angara near the mouth of its large left tributary the Yanchui River. Sculpins from the rivers Kholodnaya, Upper Angara and Yanchui have higher growth rate as compared to the ones from mountain lakes of the upper Lena basin. About 90 % of males and females matured at the age of 3 years. Absolute fecundity of two females from the Upper Angara River was 149 and 556 (with a mean of 352,5) eggs and of two females from the Kholodnaya River, 223 and 305 (with a mean of 264) eggs. This exceeds the fecundity of sculpins from mountain lakes in the Lena part of Baikal rift zone, which averages less than 150 eggs. Sculpins spawn in the Kholodnaya River in the 1st half of June. The diet of C. cf. poecilopus all over the Baikal basin as well as in adjacent sites in the Lena basin was basically composed of larvae of amphibious insects (trichopterans, ephemeropterans, chironomids and plecopterans). The discovery of the third species from the Lena basin in the Baikal basin following the findings of Arctic charr Salvelinus alpinus and grayling Thymallus baicalolenensis evidences the absence of differences in the structure of ichthyofaunas of the upper parts of both neighboring basins. Sculpins permeate along the streams to mountain lakes more easily than other species and colonize the most elevated ones in lake cascades within the northern part of Baikal rift zone. Their dispersal across the divide could proceed in two ways: via headwater captures or via flattened passes between converging upper reaches of adjacent streams.

The fish fauna of Lake Frolikha comprises 12 species confirmed by our recent studies: roach Rutilus rutilus (L.), minnow Phoxinus phonixus (L.), stone loach Barbatula toni (Dyb.), spine loach Cobitis melanoleuca Nichols, pike Esox lucius L. lenok Brachymystax lenok (Pallas), Arctic charr Salvelinus alpinus (L.), Baikal black grayling Thymallus baicalensis (Dyb.), burbot Lota lota (L.), sand sculpin Leocottus kesslerii (Dyb.), stone sculpin Paracottus knerii (Dyb.) and perch Perca fluviatilis L. Biological peculiarities of these fishes are determined by unique geographical position and limnic characteristics of Lake Frolikha. Being a typical glacial lake it is located at rather low altitude a.s.l. and is adjacent to the unparalleled ecosystem of Lake Baikal. An underdeveloped shallow coastal zone with sparse aquatic vegetation, which is characteristic of glacial lakes, determines some biological traits of Lake Frolikha cyprinids. As compared with other mountain lakes of Baikal Rift Zone (BRZ), roach and minnow have lower rates of linear and weight growth as well as unusual population sex ratios. Male to female ratio in roach is 2:1 and in minnow it is 1:1 whereas in other lakes it reaches 1:4 and 1:10 respectively. The presence of native Baikal species in Lake Frolikha provided abundant food for piscivores: sand sculpins are the dominant food item of lenok, Arctic charr and perch. Lenok and perch demonstrate prominent linear and weight growth rate in the lake. In other lakes of BRZ with less abundant prey fish species Arctic charr typically diverge into several trophic forms, but in Lake Frolikha they established a monomorphic mostly piscivorous population. Charr from Lake Frolikha are relatively small and short-lived representatives of the large form of Transbaikalian charr. Their unique feature is river spawning, which is not observed in any other charr population within BRZ. Due to special protection regime of the territory, which minimizes catch losses, several fish species maintain natural unaffected structure of their populations evidenced by the abundance of old fish. The population of lenok is represented by 19 age groups, the population of roach – by 15 groups and that of burbot – by 12 groups. Alternatively, populations of small-sized prey species such as minnow and sand sculpin, which are heavily influenced by numerous predators include fewer age groups than in other mountain lakes of BRZ.

We study the causes complicating the application of the tone-burst method for the calibration of underwater vector sound receivers. We describe an experiment performed to confirm the correctness of the procedure of calibration of a vector receiver by the method of moving complex weighted averaging when the sensitivity measured in the reverberating sound field cannot be compared with the results of other independent methods. As a criterion, we use the correctness of measurements of the parameters of distortions introduced by the sound waves reflected from the water–air interface in the direct wave of the emitter. The proposed technique makes it possible to experimentally establish the possibility of selection of the vector quantity of the direct wave from the emitter in the reverberating sound field formed in the water tank within the frequency range overlapping the range of the tone-burst method and extended to the frequencies of the chamber of standing sound waves.

The structure and properties of ultrafiltration membranes synthesized from bicomponent solutions in N,N-dimethylformamide using five commercial acrylonitrile copolymers of various compositions and molecular masses have been studied. The molecular mass characteristics of the copolymers (Mw, Mw/Mn) have been determined; the viscosity properties of dilute and concentrated solutions have been studied. It has been shown that depending on the chemical composition and molecular mass of the copolymer, the concentration dependence of the water flux is different: for copolymers with a molecular mass of Mw of 76 000–81 000 g/mol, with an increase in the copolymer concentration in solution from 12 to 16%, the water flux of the membranes decreases from 300–500 to 40–150 L/(m2 h) depending on the copolymer composition. For samples with a higher molecular mass (Mw = 99 000 and 107 000 g/mol), the water flux of the membranes hardly depends on the copolymer concentration in the casting solution; it is 150 and 75 L/(m2 h), respectively. The rejection factor of the membranes with a molecular mass of 40 000 g/mol for polyvinylpyrrolidone increases with increasing copolymer concentration in the casting solution regardless of the chemical composition and molecular mass of the copolymer. Scanning electron microscopy studies of the membrane structure have shown that membranes synthesized from copolymers with a higher molecular mass have a denser structure and a thicker selective layer than the respective parameters of membranes synthesized from acrylonitrile copolymers with a lower molecular mass, which are characterized by the presence of large macrovoids in the membrane matrix. These differences in the membrane structure are attributed to different viscosities of the casting solutions at identical copolymer concentrations.

BACKGROUND: Fermentation broth is a complex mixture which contains target and other organic compounds which must be continuously recovered to maintain microorganism activity. To overcome this problem, a sorption‐assisted thermopervaporation (SA‐TPV) method has been proposed, which enables the removal of volatile organics by means of evaporation, and low and nonvolatile compounds by membrane adsorption. RESULTS: A dense membrane made of polymer of intrinsic microporosity in the SA‐TPV process demonstrated stable performance (butanol flux 57.7 g m⁻² h⁻¹; separation factor butanol/water 30.4) within five months of operation with cell‐free ABE fermentation broth. Scanning electron microscopy/energy dispersive X‐ray spectroscopy analysis revealed that the proposed SA‐TPV method reduced ‘external’ membrane fouling by a factor of three. Fourier transform infrared and gas chromatography/ mass spectrometry analysis confirmed that it was possible to extract ‘external’ and ‘internal’ foulants by membrane adsorption followed by in situ regeneration. CONCLUSION: The SA‐TPV approach can be effective for recovery of both volatile and nonvolatile compounds from fermentation broth, whilst maintaining stable long‐term membrane performance. © 2019 Society of Chemical Industry

We present the results of comparison of national standards of the units of sound oscillation velocity of water particles within the range from 5 Hz to 10 kHz performed by the Hangzhou Applied Acoustics Research Institute (Pilot Laboratory) and the All-Russia Research Institute of Physicotechnical and Radio Measurements (VNIIFTRI) (COOMET 646/RU/14 Pilot Comparisons). The calibration capabilities of the participants were evaluated according to the results of measurements of the sensitivity of oscillation-velocity receivers: KGP-10, VHS56, and VHS90. At frequencies varying from 5 Hz to 500 Hz, inclusively, the calibrations were performed in a chamber as a result of comparison with a reference hydrophone performed by the method of oscillating water column. At frequencies higher than 500 Hz, we used the measuring procedure of the reciprocity method in the free field of traveling spherical sound waves. No significant inconsistencies in the calibration results were discovered at any frequency used for comparisons. The maximal discrepancies between the values of sensitivity obtained by the participants did not exceed 1.2 dB.

Graphene films were grown by the low-pressure chemical vapor deposition with a single injection of acetylene on an iron film catalyst deposited on oxidized silicon substrate. After treatment of the graphene on the iron film with aqueous solution of iron nitrate the structures consisting of quasi-suspended graphene on reaction products of the iron film with iron nitrate were obtained. The electron transport and magnetotransport properties of the films were investigated. The films have a low resistance of 80 Ohm sq−1 and a high sheet carrier density (8 × 1013 cm−2 at room temperature). At temperatures less than 200 K, the dependence of the Hall resistance on the magnetic field is like the abnormal Hall effect. Large positive linear magnetoresistance at a room temperature (60–100%) was observed in the films in a field of 0.6 T, which is attractive for creating magnetoresistive sensors. It was found that the critical magnetic field at which the MR becomes linear is very small (116–650 Oe) and linearly dependent on a temperature. The MR is proportional to the average mobility 〈µ〉. At low temperatures, the magnetoresistance increases with increasing temperature. At higher temperatures the MR decreases with increasing temperature.

In the system of lakes Bol’shoe Leprindo and Maloe Leprindo (Lena basin, Transbaikalia), spawning of two isolated populations of the dwarf form of Arctic charr Salvelinus alpinus was studied. The results supplemented with the data about the exterminated large form from these lakes, demonstrate a unique combination of sympatric and parapatric charr forms with autumn (large form), summer (dwarf form, Bol’shoe Leprindo) and first recorded in Russia winter-spring (dwarf form, Maloe Leprindo) spawning peaks. In both lakes, the dwarf form spawns in the profundal zone at silty bottom at the depth 25–58 m: in Bol’shoe Leprindo, from late June to October with peak in July-August when water temperature is 5–6°С, in Maloe Leprindo from January to July, with peak in January–March when temperature is 2.5–3.0°С. Eggs laid in July–August in Bol’shoe Leprindo develop for 3.0–3.5 months, eggs laid in January–March in Maloe Leprindo, for about 4.0–4.5 month; in both lakes they are actively consumed by burbot Lota lota. Due to smaller egg size the dwarf form has twice as high individual relative fecundity as the large form, which compensates for high egg mortality. It is supposed that the differences in spawning strategies were formed as the result of outcompeting of the dwarf form by the large form from the littoral to the profundal zone, where perennial low temperature favoured the prolongation and displacement of their spawning time. These differences determined reproductive isolation and genetic divergence between three charr populations.

A study of the parasitic fauna of the common ruff from Tsipo-Tsipikanskiye lakes (Baunt and Large Kapylushi) has made it possible to identify 19 species, including 12 in the first Lake Baunt and 15 in the second Lake Large Kapylushi. A study of the parasitic fauna of the common ruff in Lake Baunt has been carried out for the first time. Ten species of parasites (ciliates Apiosoma campanulatum and Trichodina sp., monogeneans Dactylogyrus hemiamphibothrium and Gyrodactylus sp., cestodes Cyathocephalus truncatus and Proteocephalus cernuae, trematodes Diplostomum volvens and Tylodelphys clavata, the nematode Raphidascaris acus, and acantocephalan Pseudoechinorynchus borealis) have been recorded in the common ruff from Tsipo-Tsipikanskiye lakes for the first time.

A macroscopic object equipped with synchronized clocks is examined. General physical relations are directly derived from Lorentz transformations for the case of one-dimensional motion (along the X axis) – the uncertainty relation of the object's x coordinate and the projection of its impulse along the X axis, px, and the uncertainty relation of the object's observation time, t, and its energy, E. The relations take the form: \(\Delta\)px\(\Delta\)x \(\ge\) H and \(\Delta\)E\(\Delta\)t \(\ge\) H. The H value in the relation has action dimensions and is dependent upon the precision of the rod's clocks and its mass. It is shown that if the macroscopic object in and of itself performs the function of an ideal physical clock, the relations derived in the limiting case then take the form of \(\Delta\)px\(\Delta\)x \(\ge\) h and \(\Delta\)E\(\Delta\)t \(\ge\) h, where h is the Planck constant.

The increase in the incidence of adolescents in Russia is confirmed by many special studies. An analysis of the statistic data for 2000-2015 years, showed that in Russia there was an increase in the number of adolescents (15-17 years) require for medical supervision from 410 to 486 cases per 1000 of the corresponding population (18.5%), however over the last 5 years, it declines (an average annual growth of -1.1%). The highest growth in 15 years was found in the following classes: neoplasms (126.7%), congenital anomalies (malformations) (57.6%), diseases of the musculoskeletal system and connective tissue (58.2%), diseases of the cardiovascular system (55.0%). The decrease in the number of adolescents (15-17 years) require for medical supervision for the indicated period was in three classes: some infectious and parasitic diseases (-68.2%), mental and behavioral disorders (-46.2%), injuries and poisonings (-20.8%). The balance of the number of the studied group of adolescents in 2015 was negative and amounted to -9.1% due to the excess of the number of people taken out of the register (39.0%) over the number of registered persons (48.1%), what indicates a decrease in the number of adolescents require for medical supervision. At the same time, a positive balance was observed only in two classes: injuries and poisonings (42.1%), pregnancy, deliver and puerperium (9.1%). Negative balance of the studied contingent was observed for all other classes of diseases, the highest ones: congenital anomalies (malformations) (-17.9%), mental and behavioral disorders (14.9%), respiratory diseases (-14, 2). Since the health of children and adolescents determines the health of the future nation, its preservation is an important task, the implementation of which requires the development of prophylaxis for the prevention of diseases with the definition of their targeted introduction (school, home, healthcare institutions), as well as treatment of diseases of children and adolescents, including, the format of special medical observation.

The divergence of reproductive strategies is an important development toward intraspecific diversification. We describe contrasting spawning patterns of parapatric and sympatric Arctic charr forms in two interconnected lakes Kiryalta-3 and Kiryalta-4 in Transbaikalia for comparison to charr reproduction in nine more lakes of this region. In each Kiryalta lake, two charr forms (small and large) differing in growth and diet are present, in Kiryalta-3 they are morphologically more distinct than in Kiryalta-4. In Kiryalta-3, the spawning of the small form was recorded in autumn and spring suggesting two subpopulations; spawning time of the large form is unknown. In Kiryalta-4, both forms spawn in autumn. Overall, reproductive patterns of Transbaikalian charr vary greatly in spawning time, duration, location, depth, and bottom substrate. Different populations and sympatric forms spawn in early or late autumn, spring, summer, or during more than one season, including the littoral or profundal zone, over rocks or silt, and from 1–2 weeks to at least 7 months. Peak spawning time difference between sympatric forms can reach up to 5 months, and is correlated with morphological and genetic differences. Diversification of reproductive strategies largely contributed to the emergence of exceptionally high diversity of Transbaikalian charr.

The aim of this report is to analyze the relief tiles from Halich in the wide context of applied art and architecture decor, to find the possible provenance of the craftsmen who produced them. All the relief tiles can be divided into two types, which differ in morphology (dimensions, peculiaritiesof clay mass) and style of images. Tiles of the first type are smaller, the draft is schematic, consists of outercounter line and a few inner lines. They were typical of Old Rus’ architecture by their size and shape, were produced by local craftsmen, who worked according to the local art tradition and used the motifs which they could see on the kolts. Tiles of the second type were bigger, they had not a counter but a real relief image on them, so that the picture distinctly stands out from the tile. The drawing was made carefully, with many peculiar details. Generally, the motives represented on these tiles are definitely connected with the Romanesque architectural reliefs.Tiles of the second type are a part of the European art tradition, especially their morphology is typical of European building ceramic. They were made by the foreign craftsmen, but in this case they were made in a special manner, which isn’t the same as the west analogues. The peculiarities of images of the Halich tiles confirm the conclusions drawn from the analysis of morphology.The tiles of the first type are related to the local tradition of Old Rus, the tiles of the second type belong to the imported, West European, Romanesque tradition.