https://dspace.ncfu.ru/handle/20.500.12258/48 Sun, 24 May 2026 22:14:20 GMT 2026-05-24T22:14:20Z https://dspace.ncfu.ru/handle/123456789/33007 Title: Этнические aспекты урбанизации в России Authors: Черкасов, А. А. Abstract: Данная работа посвящена изучению пространственно-временных изменений этнической структуры населения в городской местности России в период с 1959 по 2010 год. В исследовании анализируются географические особенности изменения этнической структуры городского населения страны, отдельная глава посвящена региональным особенностям этнических аспектов урбанизации, миграционным процессам полиэтничных регионов России. Fri, 01 Jan 2016 00:00:00 GMT https://dspace.ncfu.ru/handle/123456789/33007 2016-01-01T00:00:00Z https://dspace.ncfu.ru/handle/123456789/33006 Title: Coupled Electro-Thermal Modeling of the Temperature Field in an Aluminum Reduction Cell Using the Finite Difference Method Authors: Martirosyan, K. V.; Мартиросян, К. В. Abstract: The energy-intensive nature of primary aluminum production necessitates advanced computational tools for process optimization. This study presents a coupled electro-thermal model of an aluminum reduction cell, developed within the framework of smart manufacturing. Using the finite difference method (FDM) implemented in MATLAB R2025b, the model resolves the three-dimensional configuration of a cell with eight prebaked anodes across four distinct physical domains (electrolyte, anodes, cathode, and gas phase). The computational grid comprises approximately 45,000 nodes with refined vertical resolution (Δz = 0.025 m) in the interelectrode gap. The electrostatic solution converges within 150–200 iterations using successive over-relaxation (SOR, ω = 1.5), with a total runtime under 15 min for 30,000 s of simulated physical time on a standard desktop workstation. Simulation results reveal characteristic temperature profiles with maxima reaching 1150 °C and a thermal uniformity index of approximately 130 °C across the central cross-section. The predicted specific energy consumption of 14.0 MWh/t Al aligns with industrial benchmarks. This computationally accessible virtual testbed enables rapid assessment of design modifications and process parameters, supporting the goals of energy efficiency and enhanced operational stability in primary aluminum production. Thu, 01 Jan 2026 00:00:00 GMT https://dspace.ncfu.ru/handle/123456789/33006 2026-01-01T00:00:00Z https://dspace.ncfu.ru/handle/123456789/33005 Title: Skeletal Photochemical Rearrangement of 7,9-Di-tert-butyl-1-oxaspiro[4.5]deca-6,9-dien-2,8-dione Authors: Demidov, O. P.; Демидов, О. П. Abstract: Abstract: An unusual skeletal photochemical transformation of 7,9-di-tert-butyl-1-oxaspiro[4.5]deca-6,9-dien-2,8-dione (2) into 5,7-di-tert-butylspiro[2.5]octa-4,7-dien-6-one (3) and 7,10-di-tert-butyl-1-oxaspiro[4.5]deca-7,9-dien-2,6-dione (4) was observed upon irradiation of a dilute hexane solution of 2 with high-pressure UV light for 1 h. The products were isolated by column chromatography on silica gel in yields of 74% for compound 4 and 14% for compound 3. Both products were reliably characterized by NMR and HRMS. The structure of 4 was further confirmed by X-ray diffraction analysis. According to the proposed mechanism, formation of compound 3 is presumably homolytic and involves homolysis of the lactone C–O bond in the starting compound 2, release of CO2, and intramolecular recombination of the resulting biradical to form a cyclopropyl ring. The proposed pathway for the formation of oxaspiro dienone 4 from 2 may be either radical or ionic in nature. It is assumed that the initial stage of the reaction partially resembles an ionic Nazarov cyclization and proceeds through electrocyclization with the formation of cyclopentenyl-type oxyallyl cations, which, through a sequence of transformations accompanied by charge or radical transfer and extensive bond rearrangement, lead to the final product 4. The initial oxaspiro compound 2 is a known oxidative transformation product of 3,5-di-tert-butyl-4-hydroxyphenylpropionic acid (1) and its esters, which are widely used industrial antioxidants for plastics and rubbers. Compound 1, also known as phenosanoic acid or dibufelone, is used as a neuroprotective and antiepileptic drug, making this study relevant from both environmental and pharmaceutical quality control perspectives. Thu, 01 Jan 2026 00:00:00 GMT https://dspace.ncfu.ru/handle/123456789/33005 2026-01-01T00:00:00Z https://dspace.ncfu.ru/handle/123456789/33004 Title: Geological Determinism as a Conceptual Model for Solving Environmental and Engineering Problems Authors: Lauta, O. N.; Лаута, О. Н. Abstract: The article examines geological processes and phenomena that have a significant impact on the life and activities of human society. In the course of research using a number of methods, it was established that geological processes were fundamental in relation to processes occurring on the Earth’s surface and in its atmosphere. It is also substantiated that geographical determinism is a derivative of geological determinism. The leading role of geological determinism is determined by the dynamics of geological processes from ancient times to the present day and modern changes in the Earth’s geology. The article analyzes in detail tectonic faults in East Africa, northeastern Turkey, and the southwestern United States, the shift of the Earth’s magnetic poles, the magnetic anomaly in the South Atlantic Ocean, as well as the impact of human technical and technological activity on our planet. Particular attention is paid to three tectonic faults-African, Turkish, and Californian. The study showed that the African and Turkish faults are interconnected. The article emphasizes that geological processes have great importance for the formation of chemical substances and compounds in the bowels of the Earth. It is noted that the climate on Earth is largely determined by barocenters-the centers of cyclone formation. In order to minimize destructive natural and man-made consequences, humanity needs to solve engineering problems during the construction of technical facilities, taking into account current and potential geological processes and phenomena. Thu, 01 Jan 2026 00:00:00 GMT https://dspace.ncfu.ru/handle/123456789/33004 2026-01-01T00:00:00Z