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There is strong evidence that thrombotic and inflammatory mechanisms play a role in COVID-19 severity. COVID-19 morality may be reduced by common drugs that block these pathways, such as Aspirin. New Aspirin derivatives were suggested by functionalizing the benzene ring with acetate, amine, amide, and ribose at 2, 3, 4, and 5 positions. Through density functional theory (DFT) B3LYP / (6–31G), their energetic characteristics and chemical reactivity were estimated. The band gap of Aspirin is 0.199 eV, while 3-acetate Aspirin, 3-amine Aspirin, 4-amide Aspirin, and 5-ribose Aspirin have the least band gap equal to 0.187, 0.144, 0.177, and 0.162 eV, respectively. Electronegativity (χ), chemical potential (µ), hardness (η), electrophilicity index (ω), ionization potential (I), and electron affinity (A) of Aspirin are -0.166, 0.166, 0.098, -0.14, 0.265, and 0.068 eV, while for 3-amine Aspirin they are -0.130, 0.130, 0.072, -0.117, 0.202, and 0.058, respectively. On the other hand, the energy barriers of Aspirin and 3-amine Aspirin reactions with Serine are -39.286 and -152.559 Hartree, respectively. These results indicate that 3-amine Aspirin is more active than Aspirin. However, these results open the way for the development of new effective drugs for anti-inflammatory and cardiovascular diseases.

In this study, ZnO-Red Ochre nanocomposite was green synthesized by Rosa Damascena (RD) extract (RDZRONCs). Proton Induced X-ray Emission microanalysis (Micro-PIXE) and X-ray diffraction (XRD) pattern confirmed the presence of hematite (Fe2O3), and quartz (SiO2) mineral phases in the Red Ochre (RO) nanoclay. In addition, the XRD pattern shows the ZnO, ZnFe2O4, SiO2, Fe2O3, and Si phases in the RDZRONCs that were green synthesized with natural RD extract and RO. The RDZRONCs were used to modify the carbon paste electrode (CPE) for the electrochemical determination of the anticancer drug 5-fluorouracil (5-FU). Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques were employed to investigate the surface behavior of modified CPE (RDZRONCs/CPE). The electrochemical behavior of 5-FU at the RDZRONCs/CPE was exanimated by CV, differential pulse voltammetry (DPV), chronoamperometry (CA), and chronocoulometry (CC). Based on the DPV technique, a linear relationship between peak current and concentration of 5-FU was obtained in the dynamic range of 0.05–140.0 μM and with a detection limit equal to 0.0016 μM. The selectivity of RDZRONCs/CPE for 5-FU was studied in the presence of different inorganic and organic species. Also, the content of 5-FU was measured in real samples by RDZRONCs/CPE.

One of the methods of industrial dimethyl ether production is the catalytic dehydration of methanol. In this research work, methanol dehydration reactor has been modeled using continuous model and its results have been compared with experimental works and Voronoi pore network model. A 1D heterogeneous dispersed plug flow model was utilized to model an adiabatic fixed-bed reactor for the catalytic dehydration of methanol to dimethyl ether. The mass and heat transfer equations are numerically solved for the reactor. The concentration of the reactant and products and also the temperature varies along the reactor, therefore the effectiveness factor would also change in the reactor. We used the the effectiveness factor that was simulated according to the diffusion and reaction in the catalyst pellet as a Voronoi pore network model. Sensitivity analysis was performed to determine the influence of T, P and weight hourly space velocity on performance of the chemical reactor. Acceptable agreement was reached between the measured and the model data. The results showed that the maximum reaction conversion was obtained about 90 % at WHSV = 10 h−1 and T = 560 K, while the inlet temperature (Tinlet) had a greater effect on methanol conversion. In addition, the effect of water in the feed on methanol conversion was quantitatively studied. Also, the deactivation kinetics of γ-Al2O3 heterogeneous-acidic catalyst in methanol to dimethyl ether dehydration process was studied using integral analysis method. Based on independent deactivation kinetics, a second order was found that accurately fitted the experimental conversion time data. The main reaction activation energies and catalyst deactivation energies were 143.1 and −102.1 kJ/mol, respectively.