The elastic scattering of~particles near 180' was mea8»red in the vicinity of the Coulomb blrrjer for 110 112 & 114, 118Cd 112~114~118~118~120~122~124Sn 122~14, 128~128~1 30Te 144~148~iw, 152S and 204~2 08Pb. An optical-model analysis using Moods-Saxon potentials shows that the usual parameters -of the real part of the potential V R p& and a must obey the relationship V exp[pppf R0 2)/a] =0.2 MeV in order to fit the data. The~-nuc1eus distance R0 2 at which the nuclear potential depth is -0.2 MeV can then be determined for each nucleus within + 0.03 fm. An analysis in terms of a folding model was performed for 0 Pb and 4Te. For the class of potentials thus obtained, it is the o -nucleus distance at 0.5 MeV depth rather than at 0.2 MeV that appears to be best determined. The same. analysis determines the radius RFD-0 002 at which the nucleon density is 2x10 nucleon/fm . The value of RFD is found to depend mostly on the m-nucleon effective interaction used, and very little on the functional form of the density distribution. Further evidence is presented in favor of the Gaussian interaction -U0 exp(-E~2) with U0= 127 MeV and%=0. 6 fm, which has been proposed by Sumner and which leads to the probable value RFD=R0 2 -{3. 06+ 0.03) fm. Other interactions are not excluded, however, and considering those proposed so far in the literature leads to RFD=R0 2 -(3.11+0.14) fm. The average variation of R Fp with mass number is found to be (R&D) =(1. 355A +0.87) fm for spherical nuclei. The rate of variation. of |'RFD) with mass number is found to be in good agreement with the droplet model predictions, which is taken as an evidence that the surface thickness of spherical nuclei is practically constant from Sn to Pb.

One of the main protective measures against COVID-19's spread is the use of face masks. It is therefore of the utmost importance for face masks to be high functioning in terms of their filtration ability and comfort. Notwithstanding the prevalence of the commercial polypropylene face masks, its effectiveness is under contention, leaving vast room for improvement. During the pandemic, the use of at least one mask per day for each individual results in a massive number of masks that need to be safely disposed of. Fabricating biodegradable filters of high efficiency not only can protect individuals and save the environment but also can be sewed on reusable/washable cloth masks to reduce expenses. Wearing surgical masks for long periods of time, especially in hot regions, causes discomfort by irritating sensitive facial skin and warmed inhaled air. Herein, we demonstrate the fabrication of novel electrospun composites layers as face mask filters for protection against pathogens and tiny particulates. The combinatorial filter layers are made by integrating TiO 2 nanotubes as fillers into chitosan/poly(vinyl alcohol) polymeric electrospun nanofibers as the outer layer. The other two fillerfree layers, chitosan/poly(vinyl alcohol) and silk/poly(vinyl alcohol) as the middle and inner composite layers, respectively, were used for controlled protection, contamination prevention, and comfort for prolonged usage. The ASTM standards evaluation tests were adopted to evaluate the efficacy of the assembled filter, revealing high filtration efficiency compared to that of commercial surgical masks. The TiO 2 /Cs/PVA outer layer significantly reduced Staphylococcus aureus bacteria by 44.8% compared to the control, revealing the dual effect of TiO 2 and chitosan toward the infectious bacterial colonies. Additionally, molecular dynamics calculations were used to assess the mechanical properties of the filter layers.

The electrocatalytic reduction of carbon dioxide (CO2RR) into value-added fuels is a promising initiative to overcome the adverse effects of CO2 on climate change. Most electrocatalysts studied, however, overlook the harmful mining practices used to extract these catalysts in pursuit of achieving high-performance. Repurposing scrap metals to use as alternative electrocatalysts would thus hold high privilege even at the compromise of high performance. In this work, we demonstrated the repurposing of scrap brass alloys with different Zn content for the conversion of CO2 into carbon monoxide and formate. The scrap alloys were activated towards CO2RR via simple annealing in air and made more selective towards CO production through galvanic replacement with Ag. Upon galvanic replacement with Ag, the scrap brass-based electrocatalysts showed enhanced current density for CO production with better selectivity towards the formation of CO. The density functional theory (DFT) calculations were used to elucidate the potential mechanism and selectivity of the scrap brass catalysts towards CO2RR. The d-band center in the different brass samples with different Zn content was elucidated.

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