This dissertation examines growth of platinum nanoparticles from vapor deposition on SrTiO 3 using a characterization approach that combines imaging techniques and X-ray methods. The primary suite of characterization probes includes atomic force microscopy (AFM), grazing-incidence small-angle X-ray scattering (GISAXS), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and X-ray abso...

Cavity ring down absorption spectroscopy with a continuous light souree is used to measure the transition frequencies and absolute absorption coefficient of the weak b ItCv' = 2) +--X I;-Cv" = 0) transition of 02. The absorption spectrum is extracted from a measurement of the magnitude of the phase shift that an intensity modulated continuous light beam experiences upon passing through an unsta...

This study is focused on the evaluation of zinc oxide properties and behavior at commercially available cosmetic ingredients by in vitro methods of dermal absorption of zinc oxide and its subsequent chemical determinations. Two methods for determination of ZnO were used and the results were compared. The spectrophotometric method (SPM) was selected for its sensitivity and atomic absorption spec...

Mercury (Hg) is a toxicant of global concern that accumulates in organisms as methyl Hg. The production of methyl Hg by anaerobic bacteria may be limited in anoxic sediments by the sequestration of divalent Hg [Hg(II)] into a solid phase or by the formation of elemental Hg [Hg(0)]. We tested the hypothesis that nanocrystalline mackinawite (tetragonal FeS), which is abundant in sediments where H...

Presented in this paper is result of the study of the bioconcentration potential of mercury (Hg) by Suillus luteus mushroom collected from regions within Central, Eastern, and Northern regions of Europe. As determined by cold-vapor atomic absorption spectroscopy, the Hg content varied from 0.13 ± 0.05 to 0.33 ± 0.13 mg kg(-1) dry matter for caps and from 0.038 ± 0.014 to 0.095 ± 0.038 mg kg(-1)...