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Recently, Egypt had seismic activity. These seismic events have affected the stability of minarets, especially historical ones. Weight is one of the minaret's main stability factors. The main objective of the current research is to perform a three-dimensional (3D) assessment of an existing minaret, determine its accurate spatial model, document its current condition, examine its stability in the event of earthquakes, and identify the requisite measures to safeguard the minaret from any potential damage. The masonry to construct the minaret was used by extracting and examining specimens of this substance to determine its physical characteristics. The current work created three-dimensional models of the Abou-Ghanam El-Bialy minaret using a terrestrial laser scanner (TLS) to document its current condition, as well as minaret was subjected to a free vibration analysis using 3D finite element modeling. Finally, the minaret's seismic behavior was assessed utilizing mode forms, base responses, and normal stresses. The surveying method effectively documented the Minarets' existing case. The 3D seismic analysis showed that the minaret responded dynamically to earthquake loading, with mode shapes, base reactions, and normal stresses being crucial characteristics. Based on these data, we may suggest procedures to protect the minaret during seismic events. [ABSTRACT FROM AUTHOR]

Context: Egypt has a high prevalence of the hepatitis C virus (HCV) genotype 4a (GT-4a). Unfortunately, the high resistance it exhibited still was not given the deserved attention in the scientific community. There is currently no consensus on the NS5A binding site because the crystal structure of HCV NS5A has not been resolved. The prediction of the binding modes of direct-acting antivirals (DAA) with the NS5A is a point of controversy due to the fact that several research groups presented different interaction models to elucidate the NS5A binding site. Consequently, a 3D model of HCV NS5A GT-4a was constructed and evaluated using molecular dynamics (MD) simulations. The generated model implies an intriguing new orientation of the AH relative to domain I. Additionally, the probable binding modes of marketed NS5A inhibitors were explored. MD simulations validated the stability of the predicted protein–ligand complexes. The suggested model predicts that daclatasvir and similar drugs bind symmetrically to HCV NS5A GT-4a. This will allow for the development of new NS5A-directed drugs, which may result in reduced resistance and/or a wider range of effectiveness against HCV. Methods: The 3D model of HCV NS5A GT-4a was constructed using the comparative modeling approach of the web-based application Robetta. Its stability was tested with 200-ns MD simulations using the Desmond package of Schrodinger. The OPLS2005 force field was assigned for minimization, and the RMSD, RMSF, and rGyr were tracked throughout the MD simulations. Fpocket was used to identify druggable protein pockets (cavities) over the simulation trajectories. The binding modes of marketed NS5A inhibitors were then generated and refined with the aid of docking predictions made by FRED and AutoDock Vina. The stability of these drugs in complex with GT-4a was investigated by using energetic and structural analyses over MD simulations. The Prime MM-GBSA (molecular mechanics/generalized Born surface area) method was used as a validation tool after the docking stage and for the averaged clusters after the MD simulation stage. We utilized PyMOL and VMD to visualize the data. [ABSTRACT FROM AUTHOR]

• Solar distiller performance is investigated using novel detailed dynamic model. • Performance of wood side walls solar distiller is higher than that of glass ones. • Largest portion of energy loss from the solar distiller is from glass cover. • Useful portion of the distiller energy represents 39.6% of the incident energy/ • Daily energy reflected, storage, and loss represent 22, 2.9, and 35.5%, respectively. A novel transient detailed mathematical model is constructed and presented for simulation of the single slope solar still performance. The model considers all the still walls and regions including the humid air zone. Moreover, the still walls' dimensions, areas, and material properties besides the energy rate and heat exchange by convection, radiation, conduction, and condensation inside and outside the still are considered. This model estimates the temperatures, detailed energy losses and gains, and energy exchange of the still zones and walls beside still productivity and efficiency. The impact of side walls' materials; glass or wood on its performance is considered. The model is programmed and solved using MATLAB software and validated via experimental work. The results are presented under climate conditions of Assiut city, Egypt. The outcomes show that the present still model results accurately accord with the experimental results. The daily productivity per square meter of the basin area of the wooden side walls and the glass side walls stills are about 4.12 and 2.22 kg/m2, respectively. The glass cover energy loss represents the largest portion loss from the still. Besides, the convection heat loss from the humid air to the still walls is greater than that of the radiation loss and the latter from still walls to the ambient is greater than that of the convection. The daily useful portion of the incident solar energy is 39.6%, while the daily energy reflected, stored, and lost outside the still represent 22%, 2.9%, and 35.5%, respectively. [ABSTRACT FROM AUTHOR]

• Models for a natural gas power plant and a CCC plant were validated. • Controllers gain and integral time were tuned and optimized. • Four dynamic transient operations between three loads were realized. • Possibility of capturing up to 99% of carbon emissions was investigated. Cryogenic carbon capture (CCC) is one of the most recent and promising technologies for reducing carbon dioxide emissions, hence mitigating the global warming. The present research aims at exploring the feasibility of integrating it into existing thermal power plants in Egypt that are commonly operated by natural gas. A simulation model is developed using Aspen Plus Dynamics software to accurately predict the behavior of the thermal power plant after applying such integration. The model incorporates the CCC cycle established by Sustainable Energy Solutions into a natural gas power plant of Abu Qir, Egypt. The integral plant is benchmarked at various part loads scenarios. The study investigates the ability of capturing up to 99% of the emitted CO 2 and determines the consequent penalties in the generated power and the overall thermal efficiency. The results demonstrated successful integration of the thermal power plant and the CCC revealing smooth operation and safe transition between different part loads. By capturing 99% of the emitted CO 2 , both the generated power and the overall efficiency dropped maximally by 10.73%. The integration led to a maximum energy penalty of 0.840 MJe/kgCO 2 which is much smaller than other conventional carbon capture techniques. Applying this technology to all thermal power plants in Egypt, about 89 M tonnes of CO 2 emissions will be captured annually. Further integrations of CCC-ECL into other chemical and industrial facilities would significantly lead to a cleaner environment. [ABSTRACT FROM AUTHOR]

This study provides a decision support approach for selecting the best size of the main components of a small scale solar assisted, silica gel-water, adsorption cooling system in arid areas located in Assiut, Egypt. To achieve the objective of this work, an optimization based on a computer simulation has been performed on the design variables, which are: solar collector area, the volume of the hot storage tank, the volume of the cold storage tank, and thermostat set point of the auxiliary heating element. Economic and environmental evaluations of the proposed systems have been performed as well. A validation of the model results is performed with the experimental results of solar driven silica gel-water adsorption cooling system at Assiut University Campus which has worked since 2012. The results show that the tilt angle of 5 ° for the surface of the solar collectors achieved the best absorbed solar radiation by the collector filed. For all proposed systems, the solar fraction did not affect the volume of the cold water storage tank while it has a significant effect on the area of the solar collector field and as well as the volume of the hot water storage tank. The initial cost of the proposed systems ranges from 2897 €/kWc to 4808 €/kWc and this can be considered as a hindrance to spreading at the commercial level. Meanwhile, the running cost over a year achieves low values, and it ranges from 13.9 €/kWc to 99.11 €/kWc.The proposed systems of lower solar fraction give lower carbon dioxide emissions. The carbon dioxide emissions range from193 kg of CO 2eq. /kWc per year for the fully solar driven cooling system to 1062 kg of CO 2eq. /kWc per year for the cooling system fully driven by natural gas. Based on the solar saving approach the proposed system of 24 m 2 solar collector area, 0.6 m 3 hot storage tank, and 1 m 3 cold storage tank with 94 °C auxiliary heater set-point temperature can be considered as the most economically feasible solution. [ABSTRACT FROM AUTHOR]

The combined cycle power plants are the most recognized thermal power plants for their high efficiency, fast start-up capability, and relatively low environmental impact. Moreover, their flexible unit dispatch supports the share of renewable energy, which contributes to carbon mitigation. The operational flexibility of Integrated Solar Combined Cycle (ISCC) power plants is a crucial factor for reliable grid stability. To evaluate the limitations and capabilities of ISCC power plants and their control structures, dynamic simulation is a feasible method. In this study, a sophisticated dynamic process model of the ISCC power plant in Kuraymat, Egypt, has been developed using APROS software. The model describes the plant with a high level of detail including the solar field, the heat recovery steam generator, and the control structures. The model was implemented structurally identical to the reference plant and tuned using the operational design data. Actual measurements were used as the basis for the initialization and validation of the dynamic simulation environment. Dynamic analysis of four different days was performed, then the simulation results were presented and compared with actual measurements. The comparison showed that the course of the actual measurements could be predicted with high accuracy. The solar field influences and the system's overall power curves are reliably simulated. Consequently, the validated model can simulate the dynamic behavior of the ISCC power plant with a high degree of accuracy, and can be considered in future planning decisions. [ABSTRACT FROM AUTHOR]