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The influence of the parameters of a copper substrate on wettability at different temperatures was studied experimentally and theoretically. It is known that water condensation on graphene leads to a change in the electrical properties and affects graphene sensor sensitivity. To date, there are no data on the effect of temperature on the surface properties of graphene synthesized on copper. It is shown for the first time that a change in the (111), (110) and (100) crystal orientations of copper leads to different structuring of water on copper and on the graphene layer. An increase in temperature alters the density of water distribution and the pattern of water structuring. The analysis of the influence of grain boundaries on graphene synthesis is given. A change in the size of defects is shown to alter the qualitative nature of roughness for copper and graphene. Various methods of roughness processing allow explanation of the inconsistency of existing works comparing the roughness of the metal and graphene coating. The roughness measurement serves to prove the authors’ previously proposed hypothesis about the local stratification of graphene and copper due to large surface defects. The results obtained are important for the development of graphene-based sensor technologies.

The reliable and economical operation of equipment for thermal power plants, heat supply systems and boiler houses has been a relevant problem in the field of thermal power engineering for many years. In many industries, industrial steam is often used, for which steam boilers are used at thermal power plants. The water consumed by the boilers undergoes pre-treatment, which, in addition to its softening, includes thermal deaeration — the removal of aggressive gases that lead to equipment corrosion. Atmospheric deaerators are often used for this purpose. They are easy to use, quite effective, but have a disadvantage — a considerable amount of heat is lost with the removed flash steam. The article is dedicated to evaluating the cost-effectiveness of the technology for additional heating of return system water using deaerator steam and considering a method for improving the efficiency of atmospheric deaeration by partial closure of flash steam output in boiler plants. The paper presents a calculation of the scheme of operation of a deaeration plant, which makes it possible to increase the efficiency and effectiveness of the boiler house of the AB InBev Efes brewery in Ulyanovsk due to additional heating of return system water with atmospheric deaerator flash steam. The article also discusses the scheme of operation of an atmospheric deaerator, in which the flash steam will be discharged into the atmosphere only if it is necessary to remove aggressive gases. Thanks to the developed scheme, when the deaerator operates with a closed flash steam removal pipeline and without being fed with chemically purified water, the consumption of industrial steam is reduced, especially with a significant return of condensate, which increases the efficiency of the entire boiler room as a whole. According to preliminary calculations, assuming the average return of condensate from production per day of about 300 m3, the production steam savings will be 0.8 tons.

Until now, to suppress the image channel, radio receivers use a frequency preselector consisting of oscillatory circuits of the input device and a radio frequency amplifier. But the frequency preselector does not suppress strongly enough the image frequency. Therefore, two frequency conversions are often used in railway radio communication systems. For example, for station radio communications at frequencies f = 151‒156 MHz, two frequency converters with fpr1 = 24 MHz and fpr2 =1,596 MHz are used, which greatly complicates the design of the receiver.The article proposes to use a phase preselector, which is the second parallel quadrature frequency converter, the signal of which, after passing additional elements, is summed with the signal of the first frequency converter with high suppression of the image frequency. With this method of organising communication, the bandpass phase shifter will be a problematic block in the phase preselector, since it must have a small error Δφ.A bandpass phase shifter made on RC circuits with a minimum phase shift error Δφ = 0,1˚ within a frequency band of 25 kHz is described. In case of increasing the frequency band, the phase shift error remains minimal, but it is necessary to use limiting amplifiers to equalise the amplitudes of the signals at its output. The use of a phase preselector instead of a frequency preselector will help to reduce the intermediate frequency, which will lead to high selectivity, both in the adjacent and image channels with single-sideband modulation, and will also simplify and reduce the cost of the signal receiver.

Reliable and economical operation of the equipment of thermal heat supply systems and boiler installations is an important and challenging task. High-quality water treatment directly affects the efficiency of boiler installations. The main stages of water treatment at thermal power plants are pretreatment, desalination and thermal deaeration — removal of aggressive gases that lead to corrosion of equipment. Currently, there are a significant number of manufacturing enterprises that are equipped with their own boiler plants. In boiler houses used for steam generation, as well as heating boilers serving heating system, water deaeration is a mandatory process. The article is dedicated to the development of a technology to make the boiler installations more economical and efficient due to additional heating of the return system water with deaerator flash steam. In this paper, the process of water deaeration is considered on the example of the boiler room of the AB InBev Efes brewery in Ulyanovsk, where the heating station is equipped with automation systems, and the regulation of steam supply for heating is carried out automatically depending on the temperature of the return system water. Due to the designed arrangement and depending on the amount of flash steam of the atmospheric deaerator, the return water of the heating system can be heated by 3 - 10°C. Besides, during periods of warm winters at the Ulyanovsk-based brewery of AB InBev Efes, with minimal loads of the boiler plant, heating of the return system water in the heat exchanger with the flash steam of the atmospheric deaerator may be used as the main or additional stage of heating.

Aim. To clarify the spring aspect of the faunistic composition of Lepidoptera insects in the Republic of Dagestan as one of the most poorly studied regions of the European part of Russia.Materials and Methods. The collection of material was carried out in six localities of the Republic of Dagestan at light sources and with a butterfly net. The material was determined using modern guides.Results. We have determined 210 species of the families: Coleophoridae, Pterophoridae, Pyralidae, Crambidae, Drepanidae, Geometridae, Sphingidae, Saturniidae, Notodontidae, Erebidae and Noctuidae. Thirteen species are indicated for the fauna of Eastern Caucasus for the first time: Trypostela machinopis (Meyrick, 1936), Multicoloria vibicigerella (Zeller, 1839), Casignetella ancistron (Falkovitsh, 1976) (Coleophoridae), Gymnancyla gilvella (Ragonot, 1887) (Pyralidae), Hypena obesalis (Treitschke, 1829) (Erebidae), Clostera pigra (Hüfnagel, 1766) (Notodontidae), Cleora cinctaria ([Denis & Schiffermüller], 1775), Chlorissa pretiosaria (Staudinger, 1887), Acasis viretata (Hübner, [1799]), Earophila badiata ([Denis & Schiffermüller], 1775), Pareulype berberata ([Denis & Schiffermüller], 1775), Eupithecia assimilata (Doubleday, 1856) and Eupithecia intricata (Zetterstedt, 1839) (Geometridae).Conclusion. It seems very perspective to study the entomofauna of the Republic of Dagestan, especially in non‐standard periods: in spring and autumn.

The production of $$K^{0}_{S}$$ K S 0 mesons in inelastic p+p collisions at beam momentum 158 $$\text{ GeV }/c$$ GeV / c ( $$\sqrt{s_{NN}}=17.3$$ s NN = 17.3 $$\text{ GeV }$$ GeV ) was measured with the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron. Double-differential distributions were obtained in transverse momentum and rapidity. The mean multiplicity of $$K^{0}_{S}$$ K S 0 was determined to be $$0.162 \pm 0.001 (stat.) \pm 0.011 (sys.)$$ 0.162 ± 0.001 ( s t a t . ) ± 0.011 ( s y s . ) . The results on $$K^{0}_{S}$$ K S 0 production are compared with model predictions (EPOS 1.99, SMASH 2.0, PHSD and UrQMD 3.4 models) as well as with published world data.

Introduction (statement of the problem): Every year, about one and a half thousand convicts and persons in custody who are potential subjects of criminal liability under Article 210.1 of the Criminal Code of the Russian Federation are registered as leaders and active participants in groups of a negative orientation every year. Occupation of the highest position in the criminal hierarchy. The hypothesis of the study is that the presence of signs of a person that characterizes him as a leader or an active participant in groups of a negative orientation is a sufficient basis not only for putting on a preventive register, but also for initiating a criminal case against such a person under Article 210.1 of the Criminal Code of the Russian Federation. Moreover, preventive registration seems to be an insignificant measure to prevent the activities of a person who commits a crime. The problem of the lack of a legal definition of the concept of “a group of a negative orientation”, “a person occupying a higher position in the criminal hierarchy” is indicated. The subject of the study was Article 210.1 of the Criminal Code of the Russian Federation and the Order of the Ministry of Justice of the Russian Federation dated May 20, 2013 no. 72 “On Approval of the Instruction for the Prevention of Offenses among Persons Detained in the Institutions of the Penitentiary System”. As part of the proof of the hypothesis, the goal was to conduct a comparative analysis of the characteristics of a person who is a leader or an active participant in a negative grouping and a person occupying a higher position in the criminal hierarchy. The tasks of the study were based on its purpose, namely, they consisted in comparing the signs of “leader” and “highest position”; “grouping of negative orientation” and “criminal hierarchy”. The main research methods were the formal-legal method, which made it possible to use concepts in their legal meaning, comparative analysis, which was used when comparing the categories under study and identifying common and distinctive features, as well as the method of legal forecasting, which made it possible to assume what kind of consequences would occur if or not making changes to the legal regulation of the relations in question. The main scientific results of the study were the confirmation of the scientific hypothesis set at the beginning of the study, namely: confirmation of the fact of the identity of the categories “leader and active participant in a negative grouping” and “person occupying the highest position in the criminal hierarchy”, which will allow law enforcement agencies to initiate criminal cases on article 210.1 of the Criminal Code of the Russian Federation in relation to persons put on preventive records as leaders and active participants in groups of a negative orientation.

Abstract The effect of structure of 25 aromatic compounds on the morphology of carbon formed from them during heating to a temperature of 970°C in an inert atmosphere is studied. The specific surface area is determined for a number of products via nitrogen adsorption (28–48 m2/g). Several aromatic compounds are shown to form carbon without melting stage. X-ray phase analysis nevertheless confirms the formation of just amorphous carbon in all cases, and a negligible amount of graphite in amorphous carbon in only two cases. The thermolysis of a number of compounds is studied via synchronous thermal analysis. It is shown that slow heating during thermolysis can reduce the temperatures of transformation by tens of degrees and even alter the nature of thermolysis.

Two versions of a forward hodoscope have been developed and manufactured based on scintillation and radiation-resistant quartz plates. The hodoscopes are designed to register ions in the BM @ N experiment at the NICA accelerator complex. The light outputs and their inhomogeneity were measured as a function of the coordinates of the passage of particles through the hodoscope plates on the calibration beam of the secondary electrons of the “Pakhra” synchrotron of the Lebedev Physical Institute.

Designs of hodoscopes of nuclear fragments based on quartz and scintillation plates with light pickup by silicon avalanche photodiodes are described. Hodoscopes are planned for use in the BM@N experiment for registration of heavy nuclear fragments near the axis of the heavy ion beam. The results of measurements of light yields in detector elements based on quartz and scintillation plates on the electron beam of the synchrotron "Pakhra" (LPI) are presented. The measured nonuniformity of the light collection shows that readout from both sides of hodoscope detector elements is needed.

The physics goal of the strong interaction program of the NA61/SHINE experiment at the CERN Super Proton Synchrotron (SPS) is to study the phase diagram of hadronic matter by a scan of particle production in collisions of nuclei with various sizes at a set of energies covering the SPS energy range. This paper presents differential inclusive spectra of transverse momentum, transverse mass and rapidity of $$\pi ^{-}$$ π - mesons produced in central $${}^{40}$$ 40 Ar+ $${}^{45}$$ 45 Sc collisions at beam momenta of 13A, 19A, 30A, 40A, 75A and 150 $$A\,\text{ Ge }\text{ V }\!/\!\textit{c}$$ A Ge V / c . Energy and system size dependence of parameters of these distributions – mean transverse mass, the inverse slope parameter of transverse mass spectra, width of the rapidity distribution and mean multiplicity – are presented and discussed. Furthermore, the dependence of the ratio of the mean number of produced pions to the mean number of wounded nucleons on the collision energy was derived. The results are compared to predictions of several models.

The use of an integrated approach to the analysis of the construction of existing information systems, including not only mathematical and algorithmic, but also ontological, epistemological components, makes it possible to consider many familiar issues from a slightly different point of view. If the main criterion for the construction of a network-type information system is the time spent by radar information in the information system, and the goal is to minimize it, then the limitations introduced in the development of the traditional algorithm for tertiary processing of radar information become clear. Attempts to apply the algorithm developed for different from modern conditions and requirements lead to contradictions in the construction of information systems. The list of requirements for promising information systems obtained on the basis of the analysis of traditional tertiary processing allows us to consider the main problems of information processing and delivery from a slightly different point of view and, thus, prepare the basis for building promising information systems of a network structure.

Every year, hundreds of forest fires occur on the territory of the Siberia. It is established that in recent decades there has been an increase in the number and area of forest fires, respectively, the volume of pyrogenic emissions increases too. During fires gas-aerosol emissions are released the volume of which is determined by the intensity of the fire and the burnt forest combustible materials. The paper presents calculations of greenhouse gas emissions from fires in light coniferous forests of the Lower Angara region for 2014–2019. Using data on the amount of forest combustible materials burned in a fire, the mass of greenhouse gases released during fires is calculated, depending on the type of fire, the type of forest and weather conditions that affect the drying of combustible materials., The estimated greenhouse gas emission from fires in light coniferous forests ranges from 5.9 to 37.5 ton/ha, depending on the type of fire and the type of forest. Each year, in the light coniferous forests of the Lower Angara region, greenhouse gas emissions from fires vary from 160 to 5649 thousand tons, on average more than 2300 thousand ton/ha per year. In total, during the period under review, according to the calculated data, more than 16 million tons of greenhouse gases were released during forest fires, with a predominance of CO–CO2. It is revealed that unfavorable conditions of dispersion of emissions from forest fires are formed in the summer months, characterized by a high frequency of calm, surface inversions and radiation fogs. Relatively favorable weather conditions in the presence of pollution factors for self-cleaning the atmosphere from fire emissions are observed in spring and autumn, when the greatest number of windy days is recorded.

This review focuses on the processes involved in producing heat-resistant matrices for fiber reinforced plastics (FRP) by polymerization of the resins consisting of phthalonitrile monomers and comonomers, and the specifics of fiber reinforced plastics fabrication technologies. Polymerization behaviors observed in the presence of various types of initiators and in different temperature modes are reviewed. Fabrication methods and mechanical properties of FRPs based on phthalonitrile resins with various reinforcing materials are discussed. Properties of glass fiber reinforced plastics (GFRP) and carbon fiber reinforced plastics (CFRP) obtained through curing of different phthalonitriles are compared.

The NA61/SHINE experiment at the CERN Super Proton Synchrotron (SPS) studies the onset of deconfinement in hadron matter by a scan of particle production in collisions of nuclei with various sizes at a set of energies covering the SPS energy range. This paper presents results on inclusive double-differential spectra, transverse momentum and rapidity distributions and mean multiplicities of $$\pi ^\pm $$ π ± , $$K^\pm $$ K ± , p and $$\bar{p}$$ p ¯ produced in the 20% most central $$^7$$ 7 Be+ $$^9$$ 9 Be collisions at beam momenta of 19A, 30A, 40A, 75A and 150A $${\mathrm{Ge} \mathrm{V}}\!/\!c$$ Ge V / c . The energy dependence of the $$K^\pm $$ K ± / $$\pi ^\pm $$ π ± ratios as well as of inverse slope parameters of the $$K^\pm $$ K ± transverse mass distributions are close to those found in inelastic p+p reactions. The new results are compared to the world data on p+p and Pb+Pb collisions as well as to predictions of the Epos, Urqmd, Ampt, Phsd and Smash models.

We examine whether some well-known properties of partial recursive functions are valid for ITBM-computable functions, i.e., functions which can be computed with infinite time Blum–Shub–Smale machines. It is shown that properties of graphs of ITBM-computable functions differ from the usual properties of graphs of partial recursive functions. All possible ranges of ITBM-computable functions are described, and we consider the existence problem for ITBM-computable bijections between ITBM-computable sets of the same cardinality.

A novel strategy to design "turn-on" fluorescent receptors for G-quadruplexes of DNA is presented, which relies on the connection of phosphate binding macrocycles (PBM) with naphthalimide dyes. A new PBM-dye family was synthesized and evaluated in terms of binding and detection of nucleotides and DNA G-quadruplexes of different topologies.

Based on the results of triaxial tests for sands of various particle-size distribution, a statistical assessment of the dependence of Reynolds dilatancy on the parameters of density and stress state was carried out. An improved model, which takes into account the dependence of the dilatancy angle on the current and residual void ratios and the effective stress level, is proposed. Recommendations are given on the use of research results in the practice of geotechnical calculations.

A measurement of charged hadron pair correlations in two-dimensional $$\Delta \eta \Delta \phi $$ Δ η Δ ϕ space is presented. The analysis is based on total 30 million central Be + Be collisions observed in the NA61/SHINE detector at the CERN SPS for incident beam momenta of 19A, 30A, 40A, 75A, and 150A $$\text {Ge} \text {V}/c$$ Ge / c . Measurements were carried out for unlike-sign and like-sign charge hadron pairs independently. The $$C(\Delta \eta ,\Delta \phi )$$ C ( Δ η , Δ ϕ ) correlation functions were compared with results from a similar analysis on p + p interactions at similar beam momenta per nucleon. General trends of the back-to-back correlations are similar in central Be + Be collisions and p + p interactions, but are suppressed in magnitude due to the increased combinatorial background. Predictions from the Epos and UrQMD models are compared to the measurements. Evolution of an enhancement around $$(\Delta \eta ,\Delta \phi ) = (0,0)$$ ( Δ η , Δ ϕ ) = ( 0 , 0 ) with incident energy is observed in central Be + Be collisions. It is not predicted by both models and almost non-existing in proton–proton collisions at the same momentum per nucleon.

An experimental setup for studying the Compton scattering of annihilation photons in various (entangled and decoherent) quantum states is presented. Two entangled $\gamma$-quanta with an energy of 511 keV and mutually orthogonal polarizations are produced by positron-electron annihilation in a thin aluminum plate and are emitted in opposite directions. To measure both photons, the setup provides two equivalent arms of Compton polarimeters. A Compton polarimeter consists of a plastic scintillation scatterer and an array of NaI(Tl) detectors for measuring photons deflected at an angle of 90$^\circ$. The intermediate scatterer of the GAGG scintillator with SiPM readout is inserted into one of the arms to create a tagged decoherence process prior to the measurement of annihilation photons in polarimeters. The performance of Compton scatterers and NaI(Tl) counters is discussed. The polarization modulation factor and the analyzing power of Compton polarimeters are evaluated from the angular distributions of scattered gammas. The Compton scattering of photons in entangled and decoherent states is compared reliably for the first time., Comment: 11 pages with 7 PDF figures