A comprehensive computational study on the oxygen molecule (O) adsorption and activation on bimetallic Au-Ir subnanometer clusters supported on TiO(101)- up to five atoms in size-is performed. A global optimization density functional theory-based basin-hopping algorithm is used to determine putative global minima configurations of both mono- and bimetallic clusters supported on the metal oxide surface for all sizes and compositions. Our results indicate a strong cluster-oxide interaction for monometallic Ir clusters with calculated adsorption energy (E) values ranging from -3.
View Article and Find Full Text PDFCysteine-protected metal nanoparticles (NPs) have shown interesting physicochemical properties of potential utility in biomedical applications and in the understanding of protein folding. Herein, cysteine interaction with gold, silver, and copper NPs is characterized by Raman spectroscopy and density functional theory calculations to elucidate the molecular conformation and adsorption sites for each metal. The experimental analysis of Raman spectra upon adsorption with respect to free cysteine indicates that while the C-S bond and carboxyl group are similarly affected by adsorption on the three metal NPs, the amino group is sterically influenced by the electronegativity of each metal, causing a greater modification in the case of gold NPs.
View Article and Find Full Text PDFAn unusual case of obstruction of the iliac veins by a markedly distended urinary bladder (UB) is presented. Initial radionuclide venography (RNV) was positive, revealing obstruction of the iliac veins associated with marked dilatation of the UB. After the UB was emptied, RNV was negative.
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