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The problems of energy supply in isolated villages of theRepublic of Sakha (Yakutia) are considered. Mapping of the resourcepotential of wind energy in the Republic of Sakha was performed. Based onthe performance modeling data of the Komai Haltec KWT300 wind turbine,the territory was zoned according to the level of wind potential. The analysisof the possibilities of energy substitution by the use of wind energy in thenorthern region of Yakutia in zones of decentralized energy supply wascarried out. Using GIS tools, a multifactorial analysis of the territory basedon the level of accessibility of power lines, transport routes and the presenceof environmental restrictions, especially nesting and bird habitats (ImportantBird Area in Republic of Sakha) was fulfilled.

One of the main tasks in designing heat accumulators for renewable energy installations is accurately calculating the temperature and energy intensity of the heat accumulator. In recent years, based on the use of modern technologies, it has become possible to obtain building materials with high characteristics of the heat-accumulating medium. In order to increase the efficiency and reliability of heat accumulators, as well as the optimal choice of elements for building structures, there is a need to improve methods for calculating their operating modes based on the creation of numerical models. The article considers the principles of creating heat accumulators based on various heat storage media. Based on the system of differential equations of motion of the coolant and thermal conductivity, a mathematical model of the solar heat accumulator is constructed and a program for its numerical solution is developed. The fields of temperature distributions inside an underground heat accumulator with different warm-up times were obtained and the average daily temperature of the working fluid of the heat accumulator based on gravel and zeolite was determined. It is shown that in comparison with a gravel accumulator, the energy efficiency of a zeolite is twice as high, and the volume of the chamber of a zeolite accumulator can be twice as small as a gravel one with the same efficiency of its operation. Recommendations are given on the selection of various heat storage materials, with an assessment of their applicability and availability. The subject of research: methods for calculating the temperature and energy consumption of elements of building structures of heat accumulators. Objectives: improvement of methods for calculating the temperature and energy consumption of building elements of heat accumulators. Materials and methods: the proposed method is based on the possibility of creating a numerical model of a heat accumulator heated by solar radiation to simulate the dynamics of changes in the average temperature of the heat accumulating material over time. Results: A theoretical calculation of the temperature and energy consumption of the heat accumulator is proposed. Conclusions: the approach proposed in this article can be applied to energy construction.

We present multi-sensor measurements from satellites, unmanned aerial vehicle, marine radar, thermal profilers, and repeated conductivity–temperature–depth casts made in the Kara Gates strait connecting the Barents and the Kara Seas during spring tide in August 2021. Analysis of the field data during an 18-h period from four stations provides evidence that a complex sill in the Kara Gates is the site of regular production of intense large-amplitude nonlinear internal waves. Satellite data show a presence of a relatively warm northeastward surface current from the Barents Sea toward the Kara Sea attaining 0.8–0.9 m/s. Triangle-shaped measurements using three thermal profilers revealed pronounced vertical thermocline oscillations up to 40 m associated with propagation of short-period nonlinear internal waves of depression generated by stratified flow passing a system of shallow sills in the strait. The most intense waves were recorded during the ebb tide slackening and reversal when the background flow was predominantly supercritical. Observed internal waves had wavelengths of ~100 m and traveled northeastward with phase speeds of 0.8–0.9 m/s. The total internal wave energy per unit crest length for the largest waves was estimated to be equal to 1.0–1.8 MJ/m. [ABSTRACT FROM AUTHOR]

The article offers an information about the work carried out on technical monitoring of the city sewerage system tunnel in the framework of the actual problem of recreating the objects of cultural heritage of St. Petersburg, which fall into the protected zone of underground engineering networks. The purpose of the study is to identify values of the stress-strain state of the tunnel lining at various stages of construction of a cultural heritage object located on the earth’s surface in the immediate nearness. For formation of a base of the analyzed values was undertaken geolocation of ground massive, conducted geodetic measurements, defined the deformation of the soil by inclinometer boreholes, was obtained graphs of precipitation the soil massive, developed by setup technology for strain gauge sensors linear displacement inside the tunnel, worked out the mathematical model in the specialized software. Analysis of the obtained results allowed us to associate values of the stress-strain state of the collector tunnel effect from the buildings under construction and structures, as well as to identify the actual task for further research to develop methods of rapid diagnosis of the stress-strain state of tunnel lining structures in terms of their special mode of operation.

Purpose: (S)-4-(3-[18F]Fluoropropyl)-L-glutamic acid ([18F]FSPG) is an L-glutamate derivative used as a PET biomarker to assess intracellular redox status in vivo through targeting of the cystine/glutamate antiporter protein, xc− transporter. In this report, we describe a radiosynthesis of [18F]FSPG for use in PET studies that address specific challenges in relation to the radiotracer purity, molar activity, and quality control testing methods. Procedures: The radiosynthesis of [18F]FSPG was performed using a customised RNPlus Research automated radiosynthesis system (Synthra GmbH, Hamburg, Germany). [18F]FSPG was labelled in the 3-fluoropropylmoiety at the 4-position of the glutamic acid backbone with fluorine-18 via substitution of nucleophilic [18F]fluoride with a protected naphthylsulfonyloxy-propyl-L-glutamate derivative. Radiochemical purity of the final product was determined by radio HPLC using a new method of direct analysis using a Hypercarb C18 column. Results: The average radioactivity yield of [18F]FSPG was 4.2 GBq (range, 3.4–4.8 GBq) at the end of synthesis, starting from 16 GBq of [18F]fluoride at the end of bombardment (n = 10) in a synthesis time of 50 min. The average molar activity and radioactivity volumetric concentration at the end of synthesis were 66 GBq µmol−1 (range, 48–73 GBq µmol−1) and 343–400 MBq mL−1, respectively. Conclusion: Stability tests using a 4.6 GBq dose with a radioactivity volumetric concentration of 369 MBq mL−1 at the end of synthesis showed no observable radiolysis 3 h after production. The formulated product is of high radiochemical purity (> 95%) and higher molar activity compared to previous methods and is safe to inject into mice up to 3 h after production. [ABSTRACT FROM AUTHOR]