The Complex of Experimental Facilities for the Cosmic Ray Investigation at the Tien Shan Mountain Station

The study describes the experimental complex of the station located in the Tien Shan mountains at an elevation of 3340 m above sea level. The complex consists of detectors of different types scattered across the station area, such as scintillation particles detectors, Cherenkov detectors, radio emission detectors for the measurement of the electron component of extensive air showers (EAS) created by the (1–1000) PeV cosmic ray particles, an ionization calorimeter and neutron detectors for the study of the nuclear-active component of EAS cores, and the underground particle detectors for the detection of cosmic ray muons. The data acquisition system allows the simultaneous recording of parameters from various stand-alone detectors registering an EAS, and storage of the acquired data in the database. As an illustration of research capability, the results of the EAS study are presented here which were obtained during the last few years at the different experimental set-ups constituting the Tien Shan complex.

Determination of thermophysical properties of prototypes of tin-lithium alloy by differential scanning calorimetry

This paper presents a description of research works to determine the thermophysical properties of a tin-lithium alloy with a different percentage of lithium and tin atoms in the alloy. The method of differential scanning calorimetry (DSC) was used for the studies, by which the thermophysical properties of the alloy (temperature of phase transition and enthalpy) were determined. The work was carried out at the TiGrA experimental complex. Studies to determine the enthalpy and temperature of phase transition of prototypes of tin-lithium alloy were carried out in the temperature range from 150°C to 500°C at a heating rate of 10°C/min. The experiments were carried out with a pristine sample of tin (reference) and prototypes of a tin-lithium alloy, the percentage of lithium in which was 20, 25 and 27 at. %. As a result of the work performed, the melting point of the prototypes was determined, which was 224°C and 218°C. The values of the specific heat of fusion (enthalpy) of the investigated alloys were determined, which amounted to 76.5 J/g, 80.7 J/g and 86.3 J/g, respectively.

Experimental investigation of steel 45 along some smooth curvilinear strain trajectory

В работе представлены экспериментальные результаты деформирования тонкостенного трубчатого образца по гладкой криволинейной траектории деформирования постоянной кривизны, в которой на каждом участке изменяется знак кривизны и смещается ее центр. Экспериментальное исследование выполнено на автоматизированном расчетноэкспериментальном комплексе СН-ЭВМ в девиаторном пространстве деформаций А.А. Ильюшина (жесткое нагружение) при одновременном комбинированном действии на тонкостенный трубчатый образец растяжения-сжатия и кручения. Исследованы скалярные и векторные свойства материала стать 45. Показано, что экспериментальные диаграммы, характеризующие скалярные и векторные свойства материала носят колебательный характер. The paper presents experimental results of deformation of a thin-walled tubular specimen along a smooth curvilinear strain trajectory of constant curvature, in which the sign of curvature changes at each section and its center shifts. Experimental data were obtained on the automated calculation-experimental complex SN-Computer in the deviator space of deformations A.A. Ilyushin (rigid loading) with a simultaneous combined action on the specimen of tensioncompression and torsion. Scalar and vector material properties of steel 45 are investigated. It is shown that experimental diagrams characterizing scalar and vector properties of the material have oscillatory character.

Scattering of laser radiation from condensed phase of heterogeneous smoky plasma

A technique for research the spatial structures of the condensed phase grains in heterogeneous smoky plasma by determining the laser scattering indicatrix modulated with a frequency of 60 kHz in three spectral intervals was developed. An experimental stand was created to register the laser scattering indicatrix on the wavelengths of 808 nm, 630 nm and 532 nm in the scattering angles range from 0 to 170º with a measurement time of 3 seconds. A program of registration and processing of measurement results on a computer has been developed. Tests of the experimental complex on the flame of metalized fuel compositions were carried out.

Geant4 simulation of the Tunka-Grande experiment

The Tunka-Grande array is part of a single experimental complex, which also includes the Tunka-133 and TAIGA-HiScORE (High Sensitivity COsmic Rays and gamma Explorer) wide-angle Cherenkov arrays, TAIGA-IACT array (Imaging Atmospheric Cherenkov Telescope) and TAGA-MUON scintillation array. This complex is located in the Tunka Valley (Buryatia Republic, Russia), 50 km from Lake Baikal. It is designed to study the energy spectrum and the mass composition of charged cosmic rays in the energy range 100 TeV - 1000 PeV, to search for diffuse gamma rays above 100 TeV and to study local sources of gamma rays with energies above 30 TeV. This report outlines 3 key points. The first is the description of the Tunka-Grande scintillation array. The second one presents the computer simulation strategy of the Tunka Grande array based on the Geant4 software. The third one is devoted to the prospects for future research in the field of cosmic ray physics and gamma-ray astronomy using simulation results.

On the Issue of Safe Use of Fiber Cement Materials in the Buildings and Structures

Fiber cement finishing materials are widely used in the construction of industrial buildings and structures due to the complex of valuable operational properties. In the Russian market there are fiber-cement panels with a variety of design solutions for their coloring and application of protective coatings. Fiber cement board is a strong and moisture-resistant composite material made from a cement-sand mixture, reinforcing cellulose fibers and special additives. Not being a non-combustible material, the fiber cement boards in accordance with the current mandatory requirements, as a decorative, finishing and facing material for walls and ceilings have restrictions on their use. Existing domestic requirements regarding the methodology for assessing the combustibility of fiber cement products largely narrow the field of using these materials. Therefore, it is advisable to develop the proposals for amending the test methods and the regulatory framework governing their fire-safe extended scope. In the course of this work execution, the main provisions of the regulatory and methodological framework that establish the requirements for the fire-safe use of fiber cement materials are analyzed. Experimental complex studies of fire hazard properties of various types of samples of the fiber cement finishing panels and slabs were carried out. It is established that fiber-cement materials belong to the class of the least fire-hazardous materials. Advisability is determined concerning the introduction to the national regulatory practice of GOST R «Building materials. Test method for fire hazard under thermal exposure with a single burner (SBI)». Classification parameters of the group of non-combustible materials NG2 were established to amend GOST R 57270—2016 (method 1). Classification parameters of the group of non-combustible materials NG2 for making changes in GOST R 57270—2016 (method 1) are established. Proposals were developed to expand the scope of application of the materials and products made of fiber cement as enclosing structures, partitions, and decorative finishes (cladding) in the buildings and structures.

Study of the electric field variation based on preliminary observations at the ENU cosmophysical complex in 2020

The atmospheric electric field Ez is the most urgent problem of study of the physics of the atmosphere and the processes occurring in it. The conducted studies show the relationship of the electric field with atmospheric processes. Monitoring its changes is necessary to solve practical problems. This article presents brief characteristics of the installation of the EFM-100 electrostatic fluxmeter of the scientific cosmophysical experimental complex at the L.N. Gumilyov Eurasian National University (ENU) and its experimental data obtained in 2020. The article presents the results of observation of atmospheric-electrical characteristics near the Earth's surface and monitoring of the electric field of the atmosphere of the city of Nur-Sultan, in particular, estimates of the variation of the electric field of the surface layer of the atmosphere during sunrise and sunset based on data obtained by the EFM-100 fluxmeter. The comparison of meteorological data with the data of the electric field strength of the atmosphere is given. The analysis of the days and months in September and October 2020, when the conditions of “good weather” were manifested, was carried out. The series of electric field data obtained at other measuring stations show the characteristic periodicity of the electric field behavior. It is established that the value of the atmospheric electric field increases during sunrise with the manifestation of the solar terminator effect. It is interesting to study the relationship between the magnitude of the electric field of the atmosphere and the intensity of the cosmic ray flux, especially in the case of Forbush effects. The data of the ENU ground-based experimental complex allows us to conduct research on the study of atmospheric physics, including atomic electricity, as well as their interaction with cosmic rays and meto-conditions.