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To evaluate the occurrence and clinical features of interstitial lung disease (ILD) in a cohort of Russian patients with primary biliary cholangitis (PBC).

To evaluate the impact of previous vaccination with Gam-COVID-Vac on all-cause mortality in hospitalized adult patients with breakthrough COVID-19.

A computational and analytical method for determining the allowances on the lateral surface of the teeth of cylindrical wheels is developed. Experimental studies carried out on a modern gear grinding machine using a highly porous abrasive wheel made it possible to give recommendations on determining the optimal values of allowances depending on the modulus and pitch circle diameter of cylindrical gear wheels. Keywords: gear grinding, grinding wheel, allowance, dressing, balancing, teeth accuracy alexandr_kalashnikov45@rambler.ru

The isomerization of n-heptane on BEA supported platinum catalysts with the addition of chlorine and fluorine as promoters was studied. The use of the halides decreased the operating temperature of the n-heptane conversion. The samples prepared at the stage of peptization showed an increase in the total conversion accompanied by a decrease in the yield of heptane isomers of 6 for chlorine and 27 wt.% for fluorine. Promotion by the halides at the stage of platinum application led to an increase in the catalyst activity without decrease in the selectivity values.

Effect of cyclohexane and benzene on the isomerization of n-heptane on Pt/BEA-Al2O3 and Pt/MORAl2O3 catalysts was studied. In the presence of catalysts with platinum deposited from a [Pt(NH3)4]Cl2 solution, cyclohexane and benzene inhibit the conversion of n-heptane. At the same time, the presence of cycloalkanes and aromatic hydrocarbons leads to an increase in the isomerization selectivity due to the suppression of side reactions of hydrocracking. Samples based on the BEA zeolite were found to be more active as compared with similar samples based on mordenite.

The effect of the water operating pressure on the external heat losses value of the shell-and-tube heat exchanger by using the heat loss recovery systems based on the Rankine steam cycle has been analyzed in the present paper. A comparative analysis of the effectiveness of insulating various sections of the outer surface of the heat exchanger casing was also carried out. The choice of the heat exchanger was determined by the design simplicity, the ability to withstand high pressures and temperatures, as well as by the fact that its design makes it easier to carry out thermal insulation.The analysis of the heat transfer processes in regenerative HE was conducted on the basis of the equations contained in the ANSYS Fluent package. When modeling heat exchange processes, the following boundary conditions have been adopted: the hot air temperature at the inlet Th is equal to 600 °C (the first option) and 800 °C (the second option); the water temperature at the inlet Tw is 16 °C; the ambient temperature Ta is 20 °C. The heat transfer coefficient α between the environment and outer surface of the HE is considered as constant.The obtained results revealed that heat losses significantly decrease only when the first section is insulated in 25% of the casing surface. After isolating 50% of the casing surface, the heat losses amount remained largely unchanged. It can also be concluded that with an increase in excess water pressure, the heat losses value decreases from ∼40% to ∼8% (at the inlet gas temperature of 800 °C) and from ∼34% to ∼7% (at the inlet gas temperature of 600 °C), when the casing surface insulating degree changes from 0% to 100% and water pressure varies from 1 to 150 atmospheres, correspondingly. This is due to the fact that the water pressure increase results in increasing the boiling point and the liquid water heating area with a high heat capacity. The latter increases the heat flux perceived by the water from the hot gas, and therefore leads to the external heat loss decrease.

The paper shows the possibility of processing benzene and toluene containing a gasoline fraction obtained under conditions of fuzzy rectification of the reforming product in the process of hydroisomerization. The octane loss caused by the presence of toluene in the feed can be made up by saturating the product with butane. The Pt/Al2O3-BEA catalyst showed steady and stable operation in the resource tests on this fraction.

We present the results of a study of mesophilic anoxygenic phototrophic Chloroflexota bacteria from Mechigmen hot spring (the Chukotka Peninsula) and Siberia. According to 16S rRNA phylogenetic analysis, these bacteria belong to Oscillochloris trichoides. However, sequencing the draft genome of the bacterium from the Chukotka and analysis of the average nucleotide identity, as well as in silico DNA-DNA hybridization, reveal that this bacterium belongs to a novel species within the Oscillochloris genus. We, therefore, propose ‘Candidatus Oscillochloris fontis’ as a novel taxon to represent this mesophilic alkaliphilic anaerobic anoxygenic phototrophic bacterium. Spectrophotometry and high-performance liquid chromatography analysis show that the bacterium possesses bacteriochlorophylls c and a, as well as lycopene, β-carotene and γ-carotene. In addition, transmission electron microscopy shows the presence of chlorosomes, polyhydroxyalkanoate- and polyphosphate-like granules. The genome of ‘Ca. Oscillochloris fontis’ and the Siberian strains of Oscillochloris sp. possess the key genes for nitrogenase complex (nifH) and ribulose-1,5-bisphosphate carboxylase/oxygenase (cbbL), as previously described for O. trichoides DG-6. The results presented here, and previously published data, show that Oscillochloris bacteria from different aquatic environments have the potential for CO2 and N2 fixation. Additionally, we describe a new primer system for the detection of RuBisCo form I.

Pt/BEA–Al2O3 catalysts for the hydroisomerization of benzene-containing gasoline fractions are studied using a model feedstock (20% benzene and 80% n-heptane). The catalysts are prepared by varying the zeolite content from 5 to 70 wt % at a constant Pt loading of 0.3 wt % in all samples, with an aqueous H2PtCl6 solution being used as the Pt precursor. The acid properties of the samples are studied by means of temperature-programmed desorption (TPD). The effect of the support’s zeolite/binder ratio on the activity of the catalysts is determined: an increase in the zeolite content raises the system’s acidity and shifts the range of the reaction toward lower temperatures. The optimum zeolite/binder ratio is found to be 30% BEA/70% Al2O3. Changing the SiO2/Al2O3 ratio of the zeolite from 25 to 40 is shown to have no noticeable effect on catalyst activity. The use of the catalysts supported on 30% BEA/70% Al2O3 in the hydroisomerization of benzenecontaining gasoline fractions can be recommended for improving environmental performance.

In this work, the developed methodology for the numerical analysis of the working process in the flow part of the recuperative shell-and-tube heat exchanger was tested and a comparative analysis of heat losses was carried out for different variants of external thermal insulation of the shell. According to the results of previous studies, solid insulation materials (mineral wool, basalt super fine fiber, polyethylene foam, foamed rubber, polyurethane foam) and vacuum and screen vacuum insulation were selected for the analysis.The analysis of working processes in the considered heat exchanger was carried out using a calculation technique based on the equations of thermal conductivity, convective heat exchange and heat exchange by radiation, as well as equations describing the motion of gas and liquid and their phase changes, contained in the ANSYS Fluent package. When modeling heat exchange processes, the following boundary conditions were are specified: the hot air inlet temperature Th is equal to 550 °C; water temperature at the inlet of the Tw is 10 °C; external ambient temperature Tex is 0 °C. The heat transfer coefficient α between the environment and the outer surface of the heat exchanger was assumed to be constant.According to the results of computational studies, we can draw the following conclusions: with regard to the object under consideration, thermal insulation allows reducing the amount of heat losses from 23% to ∼4%; The smallest losses from the investigated range of insulation are achieved using screen-vacuum insulation and its modification using screens of various degrees of blackness and quantity; for each type of insulation, as its thickness increases, losses are stabilized at a certain level, which leads to the absence of the need to increase the insulation thickness over 15 mm; even a 2 mm thermal insulation layer can significantly reduce heat loss; screening efficiency decreases with increasing number of screens (with a thermal insulation thickness of 20 mm, the efficiency of screen-vacuum insulation is approximately comparable to the efficiency of vacuum insulation with the same depth of vacuum).

Isomerization of n-heptane and its mixture with methylcyclohexane (MCH) taken in a ratio of 2/1, 1/1 and 1/2 on the Pt/WO3/ZrO2 catalyst was studied. It was found that octane number of the catalyzate increases with the MCH content in the initial feed over the temperature range of 170-270 °C. The isomerization selectivity of n-heptane and the yield of isomers do not depend on the composition of the initial feed. The yield of C5+ catalyzate with a fixed octane number also increases with the MCH content in the feed.Isomerization of n-heptane and its mixture with methylcyclohexane (MCH) taken in a ratio of 2/1, 1/1 and 1/2 on the Pt/WO3/ZrO2 catalyst was studied. It was found that octane number of the catalyzate increases with the MCH content in the initial feed over the temperature range of 170-270 °C. The isomerization selectivity of n-heptane and the yield of isomers do not depend on the composition of the initial feed. The yield of C5+ catalyzate with a fixed octane number also increases with the MCH content in the feed.

Hydroisomerization of a benzene/heptane mixture over platinum catalysts supported on BEA zeolite with alumina addition was studied. The catalyst activation conditions – temperatures of its oxidative calcination and reduction with hydrogen as well as the conditions of hydroisomerization reaction were examined. It was shown that the catalyst should be reduced in flowing hydrogen at 350°C without precalcination in an air flow. The operating temperature of the process and the catalyst selectivity to target products can be controlled by varying the liquid hourly space velocity. A decrease in the H2/feed ratio to 1/1 mol/mol leads to a substantial drop in the yield of heptanes with isomeric structure and methylcyclopentane.

Alkaline hydrotherms of the Baikal rift zone are unique systems to study the diversity of thermophilic bacteria. In this study, we present data on the phototrophic bacterial community of cyanobacterial mats from the alkaline Alla hot spring. Using a clonal analysis approach, this study evaluated the species diversity, the proportion of oxygenic and anoxygenic phototrophs and their distribution between various areas of the spring. Novel group-specific PCR primers were designed and applied to detect representatives of the Chloroflexus and Roseiflexus genera in mat samples. For the first time, the presence of Roseiflexus-like bacteria was detected in the Baikal rift zone.

The efficiency impact analysis of the heat exchangers included in the mobile compressor unit (MCU) heat losses recovery system (HLRS) on the overall system operation efficiency on the basis of the refrigeration unit applying was conducted in the paper. The study subject is the mobile compressor unit (MCU) driven by the internal combustion engine and heat losses recovery system based on the cooling loop. The research scope is the unit energy efficiency.The efficiency impact analysis of the heat exchangers included in the mobile compressor unit (MCU) heat losses recovery system (HLRS) on the overall system operation efficiency on the basis of the refrigeration unit applying was conducted in the paper. The study subject is the mobile compressor unit (MCU) driven by the internal combustion engine and heat losses recovery system based on the cooling loop. The research scope is the unit energy efficiency.

The paper provides the reducing method efficiency assessment of the heat losses into the environment due to the heat losses supply to the heat carrier flow, previously flowing through the additional water jacket including the subsequent heated heat carrier flow direction into the heat-exchanging unit main flow part. Accordingly, the main heat carrier is notionally considered as the «active» insulation. The theoretical comparative analysis of this type of insulation efficiency with regard to the modes typical for the MCU recovery systems was conducted. The study was carried out by means of the numerical method through the heat transfer processes modelling of the system «heat carrier – wall – hot gas – wall – heat carrier - environment», i.e. in the recuperative heat exchanger possible design simplified version. Thus, the comparative study and analysis subject is the design consisting in the first case of two coaxial tubes, between which the hot gas flows (internal combustion engine exhaust gases) and water flows through the axial channel, while in the second case – of three coaxial tubes with the main heat carrier (water) flowing through the axial and external circular channels. In the second case, the water mass flow rate of the external circular and internal cylindrical channels is the same. The heat transfer processes calculation analysis was conducted on the basis of the convective heat transfer, thermal conductivity and radiation heat transfer known equations implemented in the ANSYS software.

Isomerization of n-heptane over platinum catalysts supported on Y, BEA, MOR and ZSM-5 zeolites with different SiO2/Al2O3 ratio in a mixture with alumina was studied. A platinum precursor was represented by aqueous solutions of H2PtCl6 and [Pt(NH3)4]Cl2. The use of hexachloroplatinic acid was shown to increase selectivity of the reaction. Samples containing Y and BEA zeolites demonstrated the highest selectivity and yields of the target products – di- and trimethyl- substituted heptane isomers.

The thermal insulation known types efficiency and applicability theoretical comparative analysis taking into account the mobile compressor units recovery systems typical modes was conducted in the paper. The study was carried out by means of the numerical method through the heat transfer processes modelling of the system «heat carrier – wall – hot gas – wall – insulation - environment», i.e. in the recuperative heat exchanger simplified version. The three most common types of insulation: foamed and fiber thermal insulation materials and vacuum insulation were applied as the heat exchanger external insulation.

The conceptual design and proof of principle experimental results of a polarization rotator based on mirrors are presented. The device is suitable for any-angle, online rotation of the plane of polarization of high peak intensity ultrashort laser pulses. Controllable rotation of the polarization vector of short laser pulses with a broad bandwidth requires achromatic retarding plates which have a limited scalability and the substantial plate thickness can lead to pulse broadening and inaccurate polarization rotation. Polarization rotators based on reflective optical elements are preferable alternatives to wave plates especially when used in high average power or high peak intensity ultra-short laser systems. The control of the polarization state is desirable in many laser-matter interaction experiments e.g., high harmonic and attosecond pulse generation, electron, proton and ion acceleration, electron-positron pair creating, vacuum nonlinear polarization effect. The device can also serve as a beam attenuator, in combination with a linear polarizer.

Five phylogenetically similar monocultures of mesophilic filamentous anoxygenic phototrophic bacteria (FAPB) were isolated from microbial mats of low-mineral (5–28 g/L) alkaline lakes in Buryat Republic, Transbaikalia and Mongolia, as well as from biofilms of an alkaline sulfide spring (3 g/L) of the Umhei hydrothermal system (Buryat Republic). New isolates were characterized by short trichomes (15–30 μm long and ∼1 μm in diameter), straight, curved, or wavy, surrounded by a thin iron-sorbing mucous sheath. Gliding motion of the trichomes was not observed. The trichomes formed bunches consisting of several filaments. Trichomes multiply by the separation of short fragments or single cells from the parental trichome. The cells in the filaments were elongated; they contained chlorosomes, gas vesicles, poly-β-hydroxybutyrate granules, and small polyphosphate inclusions. Bacteria contained bacteriochlorophylls c and a and γ-carotene. Absorption maxima of the pigments in the cells were observed at 462, (shoulder at 515), 742, 805, and 863 nm. The organisms were strict anaerobes capable of photoautotrophic growth with sulfide as an electron donor. Elemental sulfur emerged into the medium as a result of sulfide photooxidation. The organisms were tolerant to sulfide (up to 8 mM). Best growth occurred at pH 8.0, 3–15 g/L NaCl, and 1–5 g/L sodium bicarbonate. According to phylogenetic analysis, the 16S rRNA gene sequences of the FAPB isolates formed a separate cluster most closely related to the species cluster of the family Oscillochloridaceae, suborder Chloroflexinae, order Chloroflexales, class Chloroflexi. The differences with the closest 16S rRNA gene sequences of the known FAPB were 9–10%. The formal description of a new taxon, Candidatus’ Chloroploca asiatica’ gen. nov., sp. nov., is provided.

A new budding purple nonsulfur bacterium of the genus Rhodobacter (strain Ku-2) was isolated from a mat of a moderately thermal spring (Baikal rift zone, Buryatia, Russia). The bacterium had lamellar photosynthetic membranes, which are typical of only one Rhodobacter species, Rba. blasticus. The cells contained spheroidene carotenoids and bacteriochlorophyll a (Bchl a). In vivo absorption spectrum of the cells, with the major maximum at 863 nm and an additional peak at 887 nm, is characteristic of the pigment-protein complexes of Bchl a-containing membranes. The previously described Rba. blasticus strains do not exhibit the 887-nm maximum. The new isolate was photoheterotrophic, with optimal growth occurring at 35°C, 3 g/L NaCl, and pH 7–8. The DNA G+C content was 64.4 mol %. The similarity between the 16S rRNA gene sequences of strain Ku-2 and the Rba. blasticus type strain was 98.7%. The PufM amino acid sequences of strain Ku-2 and the earlier studied Rba. blasticus type strain were 89.5 % identical. Thus, strain Ku-2 belongs to the genus Rhodobacter and is phylogenetically close to Rba. blasticus.

A novel, thermophilic filamentous anoxygenic phototrophic bacterium, strain isl-2T, was isolated from the Strokkur Geyser, Iceland. Strain isl-2T formed unbranched multicellular filaments with gliding motility. The cells formed no spores and stained Gram-negative. The existence of pili was described in a species of the genus Chloroflexus for the first time, to our knowledge. Optimal growth occurred at a pH range of 7.5–7.7 and at a temperature of 55 °C. Strain isl-2T grew photoheterotrophically under anaerobic conditions in the light and chemoheterotrophically under aerobic conditions in the dark. The major cellular fatty acids were C18 : 1ω9, C16 : 0, C18 : 0 and C18 : 0-OH. The major quinone was menaquinone-10. The photosynthetic pigments were bacteriochlorophylls c and a as well as β- and γ-carotenes. The results of phylogenetic analysis of the 16S rRNA gene sequences placed strain isl-2T into the genus Chloroflexus of the phylum Chloroflexi with Chloroflexus aggregans DSM 9485T as the closest relative (97.0 % identity). The whole-genome sequence of isl-2T was determined. Average nucleotide identity values obtained for isl-2T in comparison to available genomic sequences of other strains of members of the genus Chloroflexus were 81.4 % or less and digital DNA–DNA hybridisation values 22.8 % or less. The results of additional phylogenetic analysis of the PufLM and BchG amino acid sequences supported the separate position of the isl-2T phylotype from the phylotypes of other members of the genus Chloroflexus . On the basis of physiological and phylogenetic data as well as genomic data, it was suggested that isl-2T represents a novel species within the genus Chloroflexus , with the proposed name Chloroflexus islandicus sp. nov. The type strain of the species is isl-2T (=VKM B-2978T,=DSM 29225T,=JCM 30533T).

The paper examines the mobile compressor unit (MCU) heat losses recovery system waste heat exchanger prototype external thermal insulation types influence on the operational efficiency. The study is conducted by means of the numerical method through the modellingof the heat exchange processes carried out in the waste heat exchanger in ANSUS. Thermaflex, mineral wool, penofol, water and air were applied as the heat exchanger external insulation. The study results showed the waste heat exchanger external thermal insulationexistence or absence to have a significant impact on the heat exchanger operational efficiency.The paper examines the mobile compressor unit (MCU) heat losses recovery system waste heat exchanger prototype external thermal insulation types influence on the operational efficiency. The study is conducted by means of the numerical method through the modellingof the heat exchange processes carried out in the waste heat exchanger in ANSUS. Thermaflex, mineral wool, penofol, water and air were applied as the heat exchanger external insulation. The study results showed the waste heat exchanger external thermal insulationexistence or absence to have a significant impact on the heat exchanger operational efficiency.

This paper considers various experimental designs on the Atlas facility to study the physics of liners and determine the optimum conditions of their stable motion. In one of the versions, in comparison with the Liner Demonstration series of experiments, in which unstable liner motion was observed, it is proposed to reduce the initial liner radius without changing its mass, which, according to two-dimensional calculations, should to lead to more stable motion of the liner with unchanged velocity. It is also proposed to perform an experiment in which periodic perturbations at a certain wavelength are created on the outer surface of the liner with a simultaneous increase in its thickness. According to calculations, the growth of chaotic perturbations is stabilized in this case with the preservation of the liner velocity.

Variation of physicochemical characteristics of VP-1AP anion-exchange resin in HNO3 solutions on heating and under the action of external γ-radiation up to the absorbed dose of 5 MGy was studied. It was shown that at thermal treatment of anion exchanger with increasing HNO3 concentration and temperature and under the action of ionizing radiation the total exchange capacity (TEC) and capacity with respect to strongly basic groups (C s b g) decrease. The swelling coefficients K s w noticeably vary only in treatment in 12 M HNO3 solutions and reach a maximum of 1.4. In this case, the specific surface area of the sorbent decreases from 15.7 to 1.2 m2 g- 1. Under the action of ionizing radiation the specific surface area of the irradiated anion exchanger somewhat increases and reaches 18 m2 g- 1.

Using 50 fs ( ∼ 2×1018 W/cm2) and 2 ps ( ∼ 5×1016 W/cm2) pulses from a Ti:Sa multi-TW laser at 800 nm wavelength large Xe-clusters ( 105...106 atoms per cluster) have been excited. Absolute yield measurements of EUV-emission in a wavelength range between 10 nm and 15 nm in combination with cluster target variation were carried out. The ps-laser pulse has resulted in about 30% enhanced and spatially more uniform EUV-emission compared to fs-laser excitation. Circularly polarized laser light instead of linear polarization results in enhanced emission which is probably caused by electrons gaining higher energies by the polarization dependent optical field ionization process. An absolute emission efficiency at 13.4 nm of up to 0.8% in 2π sr and 2.2% bandwidth has been obtained.

Photoinduced intermolecular electron transfer between Rhodamine 3B and N,N-dimethylaniline has been studied in a series of seven liquids: acetonitrile, ethanol, propylene glycol, and mixtures of ethanol, 2-butanol, ethylene glycol, propylene glycol, and glycerol. In each liquid, the donor and acceptors have different diffusion constants and experience distinct dielectric properties. Ps time-dependent fluorescence measurements and steady-state fluorescence yield measurements were made and analyzed using a detailed statistical mechanical theory that includes a distance-dependent Marcus rate constant, diffusion with the hydrodynamic effect, and solvent structure. All solvent-dependent parameters necessary for calculations were measured, including dielectric constants, diffusion constants, and redox potentials, leaving the electronic coupling unknown. Taking the distance-dependence of the coupling to be β=1 A−1, data were fit to a single parameter, the coupling matrix element at contact, J0. The theory is abl...

The isotherms of excess adsorption of CH4 (atP=0.001–160 MPa), SF6 (atP=0.001–2.4 MPa), and C6H6 (atP=0.0001–0.1 MPa) on carbon adsorbents—microporous carbons CMS and FAS with developed mesoporosity and graphitized soot—were measured in the 298–408 K temperature region. Calculation of the isotherms of absolute adsorption of the total content of these substances requires knowledge of the adsorption volume, which was determined by different methods: by the Dubinin—Radushkevich equation; by the experimental isotherm of excess adsorption and the equation of absolute adsorption; by the method using the intersection of nonlinear isosteres of excess adsorption and isosteres of absolute adsorption; by the comparative plot of values of the excess C6H6 adsorption ΓFAS—Γsoor; by the method using the difference of molecular radii of adsorptives and the surface of the specific adsorbent; and by the calculation of the adsorption layer thickness using the FHH equation for mesoporous systems. The results of determination of the adsorption volume for microporous systems of these carbons agree well with each other and with the passport data for the adsorbents. Analysis of the results revealed the peculiarity of the sulfur hexafluoride adsorption related to the formation of associates on the surface of the carbon adsorbents.

Isosteres, isosteric heats, and heat capacities of methane and sulfur hexafluoride on carbons with different porosities were calculated to characterize the excess adsorption and absolute adsorption. The nonlinear character of isosteres of excess adsorption and absolute adsorption of sulfur hexafluoride on FAS carbon with developed mesoporosity was shown.