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Even before the efficacy trial results of the first coronavirus disease 2019 (COVID-19) vaccine candidates were released, many governments had already made legally binding deals with vaccine manufacturers. (1) At [...]

One of the most prominent issues in the transition to net zero emissions without carbon-based fuels today and in forthcoming years is the effective use of sustainable energy sources. In this current research, the pine sawdust biomass sourced innovative multigeneration plant is proposed and planned for the production of beneficial products. The newly arranged system comprises a Brayton cycle, a supercritical CO 2 Brayton cycle, a multi-stages flash desalination part, a PEM component, and a hot water preparation unit that aims the generate power, hydrogen, freshwater, and hot water. The study also deals with performing thermodynamic performance modeling, sustainability index assessment, and environmental impact evaluation to determine the developed system performance. Additionally, the energetic and exergetic performance approaches are operated to separate components and the entire configuration. After that, the comparison of the different energy conversion scenarios is examined on the basis of the energetic efficiency and CO 2 emission rate. The main findings specify that the developed plant can be capable of 2674 kW net power, 0.003679 kg/s of clean hydrogen, and 2.115 kg/s of distilled water. To conclude, it can be stated that the newly developed combined plant has satisfactory performance, with 44.50% energetic performance and 30.01% exergetic performance. • A novel biomass-based combined plant is proposed and examined. • The production of clean power, hydrogen, freshwater, and hot water is analyzed. • Combination and evaluation of the supercritical Brayton cycle is suggested. • A thermodynamic simulation is performed to determine system' performance. • The developed plant has 44.50% of energy efficiency. [ABSTRACT FROM AUTHOR]

Expanding energy demands and to tackle with greenhouse gas emissions require new research on the carbon-free energy conversion system, which are renewable energy sources and also hydrogen. Especially, in the coming years, green hydrogen, which is produced using renewable energy sources, will become increasingly significant. This current study presents the design and evaluation of compressed hydrogen generation and beneficial outputs, which are electricity, freshwater, heating, and cooling, with a solar-driven integrated plant. Comprehensive thermodynamic performance evaluation is conducted on the multigeneration plant through energetic and exergetic efficiency methodologies. The proposed study comprises a solar heliostat field, a supercritical Brayton plant, a transcritical Rankine plant, an ejector refrigeration cycle, a desalination process, and a hydrogen generation-compression plant. Furthermore, the innovation and importance of this work are that carbon dioxide fluid is used in the Brayton and Rankine cycle. After conducting the analysis, the findings show that the net power production capacity of the developed system is 653.4 kW. Also, net hydrogen and freshwater production capacities are determined as 2.821 k g h − 1 and 2.951 k g s − 1 . The energetic and exergetic performances of the examined research are determined as 43.77% and 19.61%, respectively. In conclusion, the maximum exergy destruction rate between the plant's sub-units is computed in the solar heliostat field with 4044 k W. • A novel solar energy-based multigeneration plant is designed. • A comprehensive thermodynamic investigation of the multigeneration plant is performed. • Supercritical and transcritical C O 2 -based power plants are used for electricity generation. • The examined plant generated 2.951 kg/s freshwater and 2.821 kg/h hydrogen. • The overall energy and exergy efficiencies are 43.77% and 19.61%, respectively. [ABSTRACT FROM AUTHOR]

Adhesive anchors are widely used in seismic strengthening applications to add new structural members or sections to existing concrete members due to their high tensile and compressive strengths, low cost, and easy and fast installation. To safely design such anchors, it is very important to know their pullout capacity under axial tensile forces. This paper explores the pullout capacity of both single and groups of adhesive anchors loaded in tension in uncracked concrete. Quadruple anchor groups were considered for group effect. To this end, 142 single anchor tests including edge effect (located near a concrete edge) and 175 quadruple group anchor tests (totally 317 tests) were obtained from literature. The formulated three-layered artificial neural network method (ANN) was trained using 75% of the data set by using different learning algorithms. The methods were tested with the remaining 25%. The variables taken into account in this study are anchor diameter, embedment length, concrete compressive strength, concrete body height, edge distance (for single anchors), and anchor spacing (for group anchors). It was determined that experimental data can be estimated to a notably close extent via the ANN model.