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In this study, corrosion control of mild steel in acidic media was conducted in the presence of polyvinyl alcohol (PVA)‐chitosan and PVA‐chitosan‐dopamine composite coatings. Weight loss, polarization, and electrochemical impedance spectroscopy (EIS) studies were conducted to study the protective mechanisms and performance of PVA‐chitosan coatings. The results showed a substantial reduction in weight loss, corrosion rates, and corrosion current densities for coated specimens indicating the effectiveness of the composite coatings. PVA‐chitosan and PVA‐chitosan‐dopamine coatings showed high inhibition efficiencies (IE) up to 90.65 % and 96.01 % respectively. The electrochemical findings were supported using surface characterization techniques such as SEM to obtain a complete understanding of the coatings' morphology and composition. The topographical analysis confirmed that dopamine significantly influenced the surface morphology and behavior of the nanocomposite. The FTIR spectrum of composite B, which combined PVA and chitosan, exhibited notable changes, including a decrease in both the intensity and frequency of the OH band. The potential of PVA‐chitosan‐dopamine coatings as effective corrosion inhibitors for mild steel in acidic environments offered practical solutions for diverse industrial applications. [ABSTRACT FROM AUTHOR]

The conventional solar still (CSS) unit faces challenges such as low productivity (Pd) and thermal efficiency (ηth) due to the limited temperature difference between the hot water and the cold interior glass cover surfaces (ΔTw-gi). This study addresses these issues by introducing enhancements in the CSS unit, incorporating a v-corrugated-type basin, internal reflecting mirror, flat-plate solar collector (FPSC) still, and FPSC nanofluids. A v-corrugated-type basin, internal reflecting mirror, FPSC still, and FPSC nanofluids elicited a significant improvement in the distillate productivity (Pd) up to approximately 22.39%, 41.72%, 70.10%, and 104.13% compared to the CSS unit. This increase in the Pd is attributed mainly to a notable raise in the ΔTw-gi, showing increments of around 34.33%, 52.32%, 77.37%, and 112.87% compared to the CSS unit. Moreover, a v-corrugated basin, internal reflecting mirror, FPSC still, and FPSC nanofluids substantially increased the average daily thermal efficiency (ηth), around 22.01%, 26.71%, 39.57%, and 56.21%, respectively. The results confirmed that integrating the v-corrugated basin, internal reflecting mirror, FPSC still, and FPSC nanofluids within a combined seawater distillation system can significantly enhance the performance of the CSS unit. These different combinations effectively raised the basin water temperature (Tw) and ΔTw-gi, consequently improving the overall performance of the solar still unit. [ABSTRACT FROM AUTHOR]

Nanoparticles have attracted substantial attention for their diverse range of applications, particularly in biomedicine applications and drug delivery, owing to their unique properties. However, their tiny size facilitates easy cellular entry, which can also lead to interactions with cellular components, potentially resulting in toxicity and undesirable effects. In this study, a novel nanocomposite formulation was developed using biopolymers, specifically ethylcellulose and collagen, as capping and stabilizing agents to create bimetallic nanoparticles including TiO2@Cr2O3 nanoparticles. Physicochemical and morphological analyses were carried out to validate the formulation's structure. The obtained characteristics emphasized the presence of a nanostructure involving bimetallic nanoparticles. This formulation exhibited excellent biological activity, including high biocompatibility with Vero and WI38 cells at concentrations of 40.4 and 52 µg/mL, respectively, as well as effective anticancer activity with significant selectivity. The IC50 values were determined to be 19 and 22 µg/mL for MCF7 and A549 cells, respectively. The antimicrobial assessment revealed the highest MIC value for A. niger at 50 µg/mL, while the lowest MIC value was observed for Gram-positive bacteria at 3.12 µg/mL. Additionally, the nanocomposite demonstrated antioxidant activity at a low concentration of 1.5 µg/mL. [ABSTRACT FROM AUTHOR]

Remote arid and coastal areas have dry climates, limited freshwater supplies, and intense solar radiation. Solar still (SS) and photovoltaic (PV) technologies are preferred for small-scale water and power demands. However, these techniques have low thermal efficiency and thus limited water productivity. A compact hybrid system with a novel design combines a solar still air gap membrane distillation process with a photovoltaic panel. Outdoor experiments revealed daily average yields of produced water and power of 5.9 kg/m2 and 0.68 kWh/m2, respectively, when solar radiation intensity was 6.4 kWh/m² . Throughout the day, the specific productivity (permeate flow) of potable water, electric power, and thermal efficiency coefficient is evaluated. The results indicate that as solar radiation increases, productivity increases. The daily yield of the hybrid system increased 1.6-fold when compared to a single-stage AGMD system and cascade solar still arrangement system, and 72% of solar energy was efficiently utilized. [ABSTRACT FROM AUTHOR]

Background Severe acute respiratory syndrome coronavirus 2 infection may be associated with a prothrombotic state, predisposing patients for a progressive disease course. We investigated whether rivaroxaban, a direct oral anticoagulant factor Xa inhibitor, would reduce coronavirus disease 2019 (COVID-19) progression. Methods Adults (N = 497) with mild COVID-19 symptoms and at high risk for COVID-19 progression based on age, body mass index, or comorbidity were randomized 1:1 to either daily oral rivaroxaban 10 mg (N = 246) or placebo equivalent (N = 251) for 21 days and followed to day 35. Primary end points were safety and progression. Absolute difference in progression risk was assessed using a stratified Miettinen and Nurminen method. Results The study was terminated after 497 of the target 600 participants were enrolled due to a prespecified interim analysis of the first 200 participants that crossed the futility boundary for the primary efficacy end point in the intent-to-treat population. Enrollees were 85% aged <65 years; 60% female; 27% Hispanic, Black, or other minorities; and 69% with ≥2 comorbidities. Rivaroxaban was well tolerated. Disease progression rates were 46 of 222 (20.7%) in rivaroxaban vs 44 of 222 (19.8%) in placebo groups, with a risk difference of –1.0 (95% confidence interval, −6.4 to 8.4; P  = .78). Conclusions We did not demonstrate an impact of rivaroxaban on disease progression in high-risk adults with mild COVID-19. There remains a critical public health gap in identifying scalable effective therapies for high-risk people in the outpatient setting to prevent COVID-19 progression. [ABSTRACT FROM AUTHOR]

The absorption efficiency of a solar collector using different types of nanofluids was improved. Experimental work was carried out to investigate the flat‐plate and evacuated‐tube collectors under outdoor conditions to produce distilled water. A pilot plant was designed and installed. The yield of distilled water at different seawater flow rates and the physical properties of nanofluids were determined. Solar intensity, water mass flow rate, and temperature were measured. The performance of the desalination unit was evaluated in the presence of carbon nanotubes in paraffin wax and ethylene glycol nanofluids. The evaporation efficiency of the flat‐plate collector was improved up to 36 % in the presence of ethylene glycol nanofluid at 80–100 °C. [ABSTRACT FROM AUTHOR]