A New Look at Calcium Digermanide CaGe2_2: A High-Performing Semimetal Transparent Conducting Material for Ge Optoelectronics

Following a recently manifested guide of how to team up infrared transparency and high electrical conductivity within semimetal materials [C. Cui $et$ $al.$ Prog. Mater. Sci. 2023, 136, 101112], we evaluate an applicability of the calcium digermanide (CaGe$_2$) thin film electrodes for the advanced Ge-based optical devices. Rigorous growth experiments were conducted to define the optimal annealing treatment and thickness of the Ca-Ge mixture for producing stable CaGe$_2$ layers with high figure of merit (FOM) as transparent conducting material. Ab-initio electronic band structure calculations and optical modeling confirmed CaGe$_2$ semimetal nature, which is responsible for a demonstrated high FOM. To test CaGe$_2$ electrodes under actual conditions, a planar Ge photodetector (PD) with metal-semiconductor-metal structure was fabricated, where CaGe$_2$/Ge interface acts as Schottky barrier. The resulting Ge PD with semimetal electrodes outperformed commercially available Ge devices in terms of both photoresponse magnitude and operated spectral range. Moreover, by using femtosecond-laser projection lithography, a mesh CaGe$_2$ electrode with the relative broadband transmittance of 90\% and sheet resistance of 20 $\Omega$/sq. was demonstrated, which further enhanced Ge PD photoresponse. Thus, obtained results suggest that CaGe$_2$ thin films have a great potential in numerous applications promoting the era of advanced Ge optoelectronics.Comment: 12 pages, 4 figure

Historical and pedagogical experience of the formation of the educational system of the Primorsky special school

The article presents the results of historical and pedagogical analysis of the educational system of the Primorsky special school. The purpose of this work is to analyze the experience of the formation and development of the adaptation system of juvenile delinquents in a special school. In the late 1960s and the first half of the 1970s, this experience was completely new in the educational system, since there were no such types of educational institutions in Soviet practice, so there was a need to find new methods to achieve educational, educational and rehabilitation tasks in work with difficult teens. This article analyzes the emerging techniques and methods of educational and social and adaptation activities of adolescents in a special school in the 70s of the twentieth century. Results. The experience of the formation of the educational system of the Primorsky special school is described, the mechanisms of the successful functioning of special schools are shown, the specifics of the relationship between teachers, educators and pupils are highlighted

Cost-effectiveness analysis of tank and base foundation diagnostics without paintwork removal

The article describes the particular qualities of application of a cylindrical steel tanks' and base foundation technical inspection method without removal of a protective covering. The model is formed and the basic parameters of an estimation of economic efficiency of carrying out of diagnostics are determined. The economic efficiency of application of the modern method of vertical steel tank examination is estimated. The high economic efficiency of the new technological method is substantiated in comparison with the traditional method. It is established that the advantage of using the innovative diagnostic method in comparison with the traditional method is fully manifested when it is necessary to maintain a large fleet of tanks. It is calculated that, given the design parameters, the savings in the use of the method proposed by the authors in the long term are 1773.2 million rubles compared with traditional. The use of a new technological method - the technology of diagnosing vertical steel tanks without removing the protective coating, allows to reduce the total cost of conducting diagnostics with a discount of 8.7 times. Dependences were obtained of the discounted volume of expenses on acquisition of the equipment and the subsequent diagnostics of vertical steel tanks on the operation time of the vertical steel tanks

Мотивация, заинтересованность, удовлетворенность – движущие силы на занятиях студентов по лыжной подготовке

The study addresses the issue of how to attract the students of non-physical specialties to ski training – a physical, health and socially significant type of activity; there is also an explanation of how such arguments in favor of such activities, increasing interest and motivation. The work contains the survey results, obtained from the second-year students (n=150): the first stage includes motivational factors in ski training – increasing a cold-resistance capacity of body (4.78±0.27), free move following the rules of safe social distance (4.65 ± 0.58), opportunity spend time in the nature, to get aesthetic pleasure (4.44 ± 0.90), opportunity to increase the aerobic capacity of the cardiovascular system through skiing (3.60 ± 1.23), when more than 90 % of the muscles are involved. Further, the main trends in improving the features and technique of ski training, which turned to be the most interesting for students, are identified: skiing at a steady pace by classical style (4.24 ± 1.23) accompanying with the desire to eliminate the technical errors – double-support sliding (143 people = 95.3 %); lack of slide (141 people = 94.0 %); poor sticks work (138 people = 92.0 %). The respondents have shown a real interest in mastering and improving the up-and-down move with different degrees (4.16 ± 0.45). The result of the study lies in defining a simple and easy-to-learn methods for improving the technique of skiing, focusing on the health improvement and dealing with the ski slopesРассмотрена проблема привлечения студентов нефизкультурных специальностей вузов к лыжной подготовке как физкультурно-оздоровительному и социально значимому виду физической нагрузки. Обоснована необходимость поиска аргументов в пользу таких занятий, повышения интереса и усиления мотивации. Приведены результаты социологического исследования среди студентов второго курса (n=150), где на первом этапе были определены факторы мотивации к лыжной подготовке: усиление степени закаливания организма и устойчивость к простудным заболеваниям (4,78±0,27), возможность свободного перемещения с необходимостью соблюдения санитарных норм (4,65±0,58), возможность побывать на природе в лесном массиве, получить эстетическое удовольствие от ее созерцания (4,44±0,90), возможность без ограничения пространства повышать аэробные возможности сердечно-сосудистой системы организма посредством ходьбы на лыжах (3,60±1,23), когда в работу вовлекается более 90 % мышц организма. Далее были определены актуальные направления совершенствования специфических качеств и технических элементов лыжной подготовки, наиболее значимые и интересные для студентов: ходьба на лыжах в равномерном темпе традиционным классическим стилем (4,24±1,23) с желанием устранить грубые ошибки в технике лыжного хода – двухопорное скольжение, отмеченное у 143 чел.– 95,3 %; практически отсутствие проката на скользящей лыже у 141 чел.– 94,0 %; очень слабое отталкивание палками у 138 чел.– 92,0 %. Очевидную заинтересованность студенты проявили в освоении и совершенствовании техники передвижения на спусках и подъемах разной крутизны (4,16±0,45). Итогом исследования стало определение простых и доступных в освоении методов совершенствования техники ходьбы на лыжах оздоровительной направленности, преодоление подъемов и спусков на лыжных трасса

Лыжная подготовка и спортивное ориентирование в блоковой программе учебной дисциплины «Физическая культура и спорт»

Together with the general health care, the training classes in Physical Culture and Sports for non-majors should focus on personal self-fulfillment thorough various forms of physical culture and sports. This has always been in the universities’ academic plans, and the current State Educational Standard (3++), which provides with 400 academic hours for Physical Culture and Sports, is not an exception. These days, the outdoor classes for students are more relevant than ever against the background of the ongoing COVID‑19 and restrictive social and sanitary measures (social distance). This work presents a module-base program and methodological support of teaching within the framework of Physical Culture and Sports discipline, including ski training, orienteering and general physical training. Each training module, which includes 8–13 comprehensive classes, is designed to implement an independent part of educational material following specific natural and climatic conditions. Its usefulness is tested through a pedagogical experiment on the students of Polytechnic School, Siberian Federal UniversityЦель учебных занятий по дисциплине «Физическая культура и спорт» для студентов нефизкультурных специальностей наряду с общим оздоровительным эффектом должна учитывать направленость на личностную самореализацию в разных формах физкультурно-спортивной практики. Это всегда находило отражение в программах обучения вузов, включая и ныне действующий Государственный образовательный стандарт третьего поколения, предусматривающий 400 академических часов для освоения программы учебной дисциплины «Физическая культура и спорт». Сегодня как никогда актуальны занятия для студентов на открытых пространствах на фоне продолжающейся эпидемии и ограничительных мер, вводимых для обеспечения безопасного расстояния между занимающимися по санитарным нормам. В данном исследовании представлено блоковое программно-методическое обеспечение учебного процесса в рамках общего курса дисциплины «Физическая культура и спорт», включающее лыжную подготовку, спортивное ориентирование и общую физическую подготовку. Каждый учебный блок, включающий 8–13 однонаправленных занятий, предназначен для реализации автономной доли учебного материала в соответствии с конкретными природно-климатическими условиями. Его эффективность подтверждена проведенным педагогическим экспериментом в учебном процессе студентов политехнического института СФ

Analysis of the stress-strain state of the process pipeline to tank junction in case of subsidence

The article presents the developed finite element model of the emergency oil discharge system pipelines with a junction to the tank. Numerical modeling was carried out in the ANSYS software complex, with the help of which the model of the junction under consideration was created, considering the geometric and physical nonlinearity of the structure. A design model for the structure deformation is proposed in case the base subsidence develops. With the help of the tabulated function, it was possible to determine the value of subsidence at which critical stresses arise in the metal. Dependences of the maximum effective stresses in the metal structures of the wall to emergency discharge system pipeline junction on the RVS-20000 subsidence values are obtained. When the tank subsidence value is 144 mm, the limiting state in the wall and the junction to the pipeline occurs and the metal passes into the state of developing plastic deformations

Modeling of storage tank settlement based on the United States standards

Up to 60% of storage tanks in operation have uneven settlement of the outer bottom contour, which often leads to accidents. Russian and foreign regulatory documents have different requirements for strain limits of metal structures. There is an increasing need for harmonizing regulatory documents. The aim of this study is to theoretically justify and to assess the possibility of applying the U.S. standards for specifying the allowable settlement of storage tanks used in Russia. The allowable uneven settlement was calculated for a vertical steel tank (VST-20000) according to API-653, a standard of the American Petroleum Institute. The calculated allowable settlement levels were compared with those established by Russian standards. Based on the finite element method, the uneven settlement development process of a storage tank was modeled. Stress-strain state parameters of tank structures were obtained at the critical levels established in API-653. Relationships of maximum equivalent stresses in VST metal structures to the vertical settlement component for settlement zones of 6 to 72 m in length were determined. When the uneven settlement zone is 6 m in length, the limit state is found to be caused by 30-mm vertical settlement, while stresses in the wall exceed 330 MPa. When the uneven settlement zone is 36 m in length, stresses reach the yield point only at 100-mm vertical settlement

Modeling of storage tank settlement based on the United States standards

Up to 60% of storage tanks in operation have uneven settlement of the outer bottom contour, which often leads to accidents. Russian and foreign regulatory documents have different requirements for strain limits of metal structures. There is an increasing need for harmonizing regulatory documents. The aim of this study is to theoretically justify and to assess the possibility of applying the U.S. standards for specifying the allowable settlement of storage tanks used in Russia. The allowable uneven settlement was calculated for a vertical steel tank (VST-20000) according to API-653, a standard of the American Petroleum Institute. The calculated allowable settlement levels were compared with those established by Russian standards. Based on the finite element method, the uneven settlement development process of a storage tank was modeled. Stress-strain state parameters of tank structures were obtained at the critical levels established in API-653. Relationships of maximum equivalent stresses in VST metal structures to the vertical settlement component for settlement zones of 6 to 72 m in length were determined. When the uneven settlement zone is 6 m in length, the limit state is found to be caused by 30-mm vertical settlement, while stresses in the wall exceed 330 MPa. When the uneven settlement zone is 36 m in length, stresses reach the yield point only at 100-mm vertical settlement

Modeling of storage tank settlement based on the United States standards

Up to 60% of storage tanks in operation have uneven settlement of the outer bottom contour, which often leads to accidents. Russian and foreign regulatory documents have different requirements for strain limits of metal structures. There is an increasing need for harmonizing regulatory documents. The aim of this study is to theoretically justify and to assess the possibility of applying the U.S. standards for specifying the allowable settlement of storage tanks used in Russia. The allowable uneven settlement was calculated for a vertical steel tank (VST-20000) according to API-653, a standard of the American Petroleum Institute. The calculated allowable settlement levels were compared with those established by Russian standards. Based on the finite element method, the uneven settlement development process of a storage tank was modeled. Stress-strain state parameters of tank structures were obtained at the critical levels established in API-653. Relationships of maximum equivalent stresses in VST metal structures to the vertical settlement component for settlement zones of 6 to 72 m in length were determined. When the uneven settlement zone is 6 m in length, the limit state is found to be caused by 30-mm vertical settlement, while stresses in the wall exceed 330 MPa. When the uneven settlement zone is 36 m in length, stresses reach the yield point only at 100-mm vertical settlement

Analysis of the stress-strain state of the process pipeline to tank junction in case of subsidence

The article presents the developed finite element model of the emergency oil discharge system pipelines with a junction to the tank. Numerical modeling was carried out in the ANSYS software complex, with the help of which the model of the junction under consideration was created, considering the geometric and physical nonlinearity of the structure. A design model for the structure deformation is proposed in case the base subsidence develops. With the help of the tabulated function, it was possible to determine the value of subsidence at which critical stresses arise in the metal. Dependences of the maximum effective stresses in the metal structures of the wall to emergency discharge system pipeline junction on the RVS-20000 subsidence values are obtained. When the tank subsidence value is 144 mm, the limiting state in the wall and the junction to the pipeline occurs and the metal passes into the state of developing plastic deformations