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The physical limitations of the amount of data stored on optical media are pushing researchers to create new materials and methods for recording and reading data. One of the promising areas is the use of fluorescent compounds. Within the framework of this work, polymer structures of optical fluorescent memory with a recording medium based on 3-(thiophene-2-carbonyl) -2- (furan-2-yl) -4n-chromen-4-one in polymethylmethacrylate have been fabricated and investigated. The concentration of chromone was 5% (wt.), Which during recording made it possible to achieve optical density values at λ = 442 nm in the range of 0.01 - 0.02 with a central layer thickness of 1-3 µm. In the structures developed, the process of two-photon information recording and fluorescent parallel reading is realized. The threshold recording power density for providing a two-photon process was (5.1 ± 0.4) 105 W/cm2.

The approaches to the synthesis of new derivatives of 2-7-dibromofluorene and benzocyclobutene have been investigated. For this purpose 9-bicyclo [4.2.0] octa-1 (6), 2,4- trien-3-yl-2,7-dibromo-9H-fluoren-9-ol was synthesized by reaction of 2,7-dibromo-fluoren -9- one with 3-benzocyclobutene magnesium bromide. The possibility of reduction and substitution of the hydroxyl group at position 9 of the obtained compound with aromatic substituents under conditions of acid catalysis is demonstrated. Target compounds were obtained in yields from 75 to 90%.

New cross-linking monomer based on 1,3-diallyl-1,3-di[bicyclo[4.2.0]octa-1,3,5-trien-3-yl]-1,3-dimethyl-siloxane (BCB-All) was synthesized and its physical properties were studied. BCB-All was incorporated into copolymer with TGM-3 and PFHDA by two stage thermal polymerization. The cross-linking of the copolymers occurs by thermo-initiated ring-opening reaction of BCB at 120-200°C. Resulting BCB-All homopolymer, BCB-All-TGM-3 (50:50), and BCB-All-PFHDA (50:50) copolymers have high thermal stability (Td5%,=464°C, 322°C, 435°C respectively) and good dielectric properties (ε=2.34-2.48 at 10HHz).

The COMET experiment focuses on searching for the direct conversion of a muon into an electron on an aluminum nucleus without emitting a neutrino (so-called \\(\\mu\\rightarrow e\\) conversion). This conversion violates the lepton flavor conservation law, a fundamental principle in the Standard Model. The COMET experiment aims to achieve the muon-to-electron conversion sensitivity on a level of \\(10^{-17}\\). The Straw Tracker System (STS) based on straw tubes could provide the necessary spatial resolution of 150 \\(\\mu\\)m to achieve an momentum resolution for 105 MeV/c electrons better than 200 keV/c. The COMET experiment will be separated into two phases. Phase-I will operate with the 3.2-kW 8-GeV-proton beam, and Phase-II will operate with the beam intensity increased to 56 kW. The STS must operate in a vacuum with the inner pressure of 1 bar applied to straws. The initial design of 10-mm-diameter straws developed for Phase-I will not be as efficient with the 20 times higher beam intensity of Phase II, but the new STS design based on 5-mm-diameter 12-\\(\\mu\\)m-thick straws could fully satisfy the required efficiency. The mechanical properties of these straws, such as sagging, displacement, and dependence of the diameter on overpressure, are discussed in this article.

Photo- and electroluminescence in p – i – n structures with compensated GaAs/AlGaAs quantum wells have been studied. Two structures with different doping profiles were studied: with spatial separation of donors and acceptors (donors are localized in quantum wells, while acceptors are localized in barriers) and without it (both donors and acceptors are localized in quantum wells). The studies were carried out in the near-IR range at helium temperatures. Luminescence lines due to electron transitions from donor states to the first heavy-hole subband ( D – hh 1) and from the first electron subband to acceptor states ( e 1– A ) have been identified. At large electric currents, the near-IR lasing due to these transitions was observed in the electroluminescence spectra. It has been found that the integrated lasing intensity related to the D – hh 1 transitions in the structure without a spatial separation of donors and acceptors was three times higher than in the structure with the spatial separation. It is these transitions that ensure effective depletion of donor levels, which is important for the donor-assisted terahertz emission at e 1– D electron transitions. The results of the work can be used in the development of electrically pumped terahertz emitters.

The paper presents the results of a study done to find the optimal shapes of matrix element partitioning on three abstract heterogeneous processors when performing multiplication operations. An abstract processor model allows applying the research results in systems with different heterogeneous architectures. To determine the optimal partitioning shape, the work uses non-rectangular candidate shapes identified by Ashley DeFlumere in her work as a result of applying the technology of redistribution of matrix elements between the processors «push»: Square Corner, Rectangle Corner, Square Rectangle, Block Rectangle, L-Rectangle, Traditional 1D Rectangular. The optimality of shapes is determined for four classes of matrix multiplication algorithms: Serial Communication with Barrier (SCB), Parallel Communication with Barrier (PCB), Serial Communication with Bulk Overlap (SCO) and Parallel Communication with Overlap (PCO). The Hockney model was used to evaluate the communication complexity of algorithms. Mathematical models of the algorithm execution time were introduced in the paper for each considered candidate shape in all algorithms. Based on the developed mathematical models, software was developed that allows to select the form of elements partitioning between processors, depending on the ratio of their speeds and latency of the transmission medium.

The development of agricultural technologies, the mechanization of the cultivation of ordinary crops for a long time has gone differently in different ways. The working bodies of agricultural machines process various materials, the number of which is increasing. In addition, the way the same material is processed often changes when trying to improve agricultural technologies. All this forces us to create new mechanisms of agriculture that were previously known. The use of replaceable gear bodies on flat cutting cultivators helps to reduce the energy intensity the process and improve the quality of non-falling soil. To protect against it, various agricultural techniques are recommended: plowing along the entire slope, deepening the arable layer, the formation of irregularities on the surface of arable land in the form of holes, intermittent furrows. The article describes the mechanized protection of the soil of the technological process and technical means for growing crops on erosive lands on the slope. Methodology for improving agricultural machinery for working on the slope of erosive dangerous lands. Ways to increase the stability of the movement of agricultural machines on slopes to improve the quality of technological operations are justified. The operating mode of the active disk needle is described.

Currently, economic growth remains the main criterion of development. However, it does come along with threats to the environment, due to its link to the increased energy consumption and carbon dioxide emissions. Decoupling can be used to break this link and stop jeopardizing the environment in the favor of economic progress. This paper focuses on the decoupling between economic growth and energy consumption in each of five Central Asian countries – Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan – from 1990 to 2014. The Tapio decoupling model was implemented in order to determine the decoupling states for each country. Gross domestic product (GDP) was used to represent the economic growth, and the total primary energy supply (TPES) described the environmental pressure. These data were obtained from the IKE World Energy Balances. Both the GDP and the TPES of most of the Central Asian countries had a parabolic trend of initial drop and further increase during the timespan analyzed. This observation can be explained by the collapse of USSR and the transition to market economy. The results of the decoupling analysis can be divided into two stages for Kazakhstan, Turkmenistan, and Uzbekistan, and into three stages for Kyrgyzstan and Tajikistan, with several different decoupling states observed during each stage. According to the results, the main decoupling states in Central Asia were expansive negative decoupling, expansive coupling, weak decoupling, and strong decoupling. The analysis showed that there is a serious environmental pressure on the economic development in Central Asia.

The RBMK design-stage service life was assumed to be 30 years. Ten power-generating units have now exceeded this limit. Service life extension of nuclear power plants is a common practice in countries using nuclear energy. This approach was also applied to power-generating units with RBMK-1000 with servicelife extension to 45 years or more. To maintain electricity production in NPPs with RBMK, a technology for restoring the service-life characteristics was developed and implemented in the No. 1 unit of the Leningradskaya NPP. The results of the adoption of this technology in combination with experimental and computational validation of safety made it possible to extend the operation of the No. 1 unit of the Leningradskaya NPP in the power-generation mode since December 2013. Similar work was subsequently successfully completed in other power-generating units with RBMK.

The conceptual principles of a long-term strategy for the development of large-scale nuclear power in Russia based on fast reactors with natural safety and a closed NFC, conservation of the natural radioactivity balance for buried wastes, prevention of proliferation of weapons-grade materials, drawing uranium resources fully into energy production and ensuring that the nuclear method of electricity production is competitive are examined. The principal problems of nuclear power are characterized and ways to solve them are proposed. Mathematical models are used to examine scenarios for the development of nuclear power and the transition to a closed NFC.