Submicron and nanosized powders have gained significant attention in recent decades due to their broad applicability in various fields. This work focuses on ultrasonic spray pyrolysis, an efficient and flexible method that employs an aerosol process to synthesize titanium-based nanoparticles by transforming titanium oxy-sulfate. Various parameters are monitored to better optimize the process and obtain better results. Taking that into account, the influence of temperature on the transformation of titanium oxy-sulfate was monitored between 700 and 1000 °C. In addition to the temperature, the concentration of the starting solution was also changed, and the flow of hydrogen and argon was studied. The obtained titanium-based powders had spherical morphology with different particle sizes, from nanometer to submicron, depending on the influence of reaction parameters. The control of the oxygen content during synthesis is significant in determining the structure of the final powder.

For the COVID-19 pandemic caused by SARS-CoV-2, there are currently no effective drugs or vaccines to treat this coronavirus infection. In this study, we focus on the main protease enzyme of SARS-CoV-2, 3CL pro , which is critical for viral replication. We employ explicit solvent molecular dynamics simulations of about 150 compounds docked into 3CL pro ’s binding site and that had emerged as good main protease ligands from our previous in silico screening of over 1.2 million compounds. By incoporating protein dynamics and applying a range of structural descriptors, such as the ability to form specific contacts with the catalytic dyad residues of 3CL pro and the structural fluctuations of the ligands in the binding site, we are able to further refine our compound selection. Fourteen compounds including estradiol shown to be the most promising based on our calculations were procured and screened against recombinant 3CL pro in a fluorescence assay. Eight of these compounds have significant activity in inhibiting the SARS-CoV-2 main protease. Among these are corilagin, a gallotannin, and lurasidone, an antipsychotic drug, which emerged as the most promising natural product and drug, respectively, and might thus be candidates for drug repurposing for the treatment of COVID-19. In addition, we also tested the inhibitory activity of testosterone, and our results reveal testosterone as possessing moderate inhibitory potency against the 3CL pro enzyme, which may thus provide an explanation why older men are more severely affected by COVID-19.

This study investigated how acid concentration affects leaching from pyrolyzed LIBs’ (lithium-ion batteries’) black mass (BM) by stepwise acidification with eight acids at 70 °C under identical starting conditions. A citric-acid control without BM matched the calculated pH, whereas BM buffered solutions to ∼pH 9.5 and increased the measured pH. Stabilized pH provided a consistent reference within each experiment, but similar pH values across acids produced very different leaching efficiencies. At pH ≈ 3, lithium leaching was ∼pH 85% for formic acid and ∼pH 60% for citric acid. The maximum lithium leaching ranged from 49% (ascorbic acid) to 92% (sulfuric acid), while organic acids often showed limited cobalt and nickel dissolution. For formic acid, speciation and metal-formate solubility calculations showed that higher acid concentration does not necessarily increase transition-metal leaching and may suppress cobalt and nickel. Thus, pH is stable within each acid system but not transferable across acids, and high solid loading (250 g L⁻¹) further requires acid-specific evaluation. The results indicate that acid-dependent speciation and complexation, rather than proton concentration alone, control extraction and can decouple acid dosage from leaching performance.