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Renewable energy has become more popular since it is cost-effective and more efficient than conventional energy sources. Biomass-based renewable energy is primarily used in emerging economies to ensure environmental sustainability. This study examines the asymmetric correlation between biomass energy consumption and CO2 emissions in the top-10 biomass energy consumer countries (Brazil, Canada, Thailand, China, Italy, India, Germany, USA, UK, and Japan). A new approach "Quantile-onQuantile (QQ)" is employed by utilizing the data from 1991 to 2018. Biomass energy consumption, with the exception of Thailand, significantly mitigates CO2 emissions at various quantiles in selected countries. As a robustness check, we used the quantile regression test, whose findings are consistent with the outcomes from the quantile-on-quantile method. However, the degree of asymmetry in the biomass energy-CO2 nexus varies by country, necessitating extra attention and government vigilance when developing biomass energy and environmental policies.

This article considers the technology of fabricating clusters of nickel atoms in a silicon crystalline lattice with controlled parameters. Silicon solar cells with clusters of nickel atoms have been fabricated and their parameters determined. It has been established that the content of nickel atoms in the lattice makes it possible to considerably expand the spectral sensitivity region of silicon photovoltaic cells to the IR range up to 4 μm.

Abstract In order to improve the energy characteristics for low-power ozone generators, it is proposed to use a continuous discharge burning mode. It is due to a significant phase shift between the currents and voltages on the ozone generator. Conditions for conducting the continuous discharge mode were identified.

This article deals with the worked out specialized railway carriage for grain for the transportation process throughout the Republic of Uzbekistan railway network, with the unconditional provision of train traffic safety, which is one of the most important components of the rolling stock of railway transport. The features of the load-bearing structure of the railway carriage for grain are that it is made based on a four-axle platform and a universal container. Evaluation of the strength of the metal structure of the grain car was carried out following the requirements of the “Standards for the calculation and design of new and modernized cars of the railways of the Ministry of Railways with a gauge of 1520 mm (non-self-propelled)”. Based on theoretical studies, it was justified that the design of a railway carriage for grain with a capacity of 83.6 m3 and a carrying capacity of 65 tons. For the first test of a railway carriage for grain, the number 43925684 was assigned. The proposed new grain carriage will reduce operating costs and reduce rolling stock downtime during reloading operations. It will create the possibility of fulfilling contractual agreements drawn up for small volumes of traffic within the country.

This article discusses the loss of bioindicator characteristics in oribatid mites found in the Kashkadarya region due to various anthropogenic and environmental factors. The study, conducted during the spring and summer of 2023, focused on pine and spruce gardens surrounding the Shortan gas-chemical industrial area. The results of our research identified 23 species, including Ornithonyssus bursa, Geratoppia quadridentate, Furcoribula furcillata, Perlohmannia altaica, Liochthonius kirghisicus, Asiacarius elongatus, Liochthonius hystricinus, Cultroribula dentata, Epilohmannia cylindrica and Michelia paradoxa with bioindicator properties. Changes in these indicators of species primarily occurred in the A soil layer, up to 10 cm deep. The study found that the primary factor influencing these changes was not the chemical waste from the industrial plant but rather acid gases resulting from burning companion gases, leading to acid rain formation when mixed with precipitation.

Abstract Methods of calculating the shell structures from composite materials and studying the concentration of strains near the holes are devoted to a rather large number of works. However, most of the research was carried out within the framework of the classical Kirchhoff-Love hypothesis, which does not take into account the interlayer and lateral shifts characteristic of composite materials. Application of finite elements method to solve the problems on orthotropic shells of composites, weakened by several holes is reported within the improved theory of Timoshenko type. A numerical algorithm has been developed using the finite element method and a software package has been implemented on a computer that makes it possible to solve problems of stress concentration near two apertures in shells of composite materials. Shearing parameter has been studied for its influence on stress concentration near two circular holes internal pressure for orthotropic spherical shells. Specific results are presented for the cases of large and small holes, taking into account the rigidity of the reinforcing elements. Thus, this software package can be applied to the calculation of the elements of shell structures from orthotropic composite materials weakened by several holes.

In this article, the optimal design of a novel multi-generation system for the production of electricity, cooling, heat and freshwater is discussed. In this system, a Proton exchange membrane fuel cell (PEM FC) is used to generate electricity, and the heat produced by it is absorbed by the Ejector Refrigeration Cycle (ERC) and used to provide cooling and heating capacity. A reverse osmosis (RO) desalination system is also used to supply freshwater. The esign variables in this research are operating temperature and pressure and current density of FC, as well as the operating pressure of the HRVG, evaporator, and condenser of the ERC system. In order to optimize the considered system, the exergy efficiency and total cost rate (TCR) of the system are considered as optimization objective functions. To this end, the genetic algorithm (GA) is used and the Pareto front is extracted. Also, three refrigerants R134a, R600 and R123 areused as ERC system refrigerant and their performance are evaluated. Finally, the optimal design point is selected. At the mentioned point, the exergy efficiency is 70.2% and the TCR of the system is 1.78 S/h.