Gallium-selenide films grown by heteroepitaxy on silicon substrates exhibit two primary growth structures: layered GaSe and defected zinc-blende Ga2Se3. The latter is seen when growing on the (100) surface of silicon, and an emergent structure of nanowires is observed. My project for the ten week summer program at the University of Washington physics department was to investigate the nanowire s...

Chromium is an essential nutrient involved in the metabolism of glucose, insulin and blood lipids. Suboptimal dietary intake of chromium is associated with increased risk factors associated with diabetes and cardiovascular diseases. Within the past five years, chromium has been shown to improve glucose and related variables in subjects with glucose intolerance and type 1, type 2, gestational an...

There are no two main-group elements that exhibit more similar physical and chemical properties than sulfur and selenium. Nonetheless, Nature has deemed both essential for life and has found a way to exploit the subtle unique properties of selenium to include it in biochemistry despite its congener sulfur being 10,000 times more abundant. Selenium is more easily oxidized and it is kinetically m...

A novel radio frequency magnetron sputtering method for the deposition of composite films which consist of chromium oxide and chromium ~Cr2O3/Cr-cermet! is presented. As an extension to conventional reactive sputtering of a Cr target in an argon and oxygen atmosphere the oxygen flow into the process chamber is switched periodically on and off. This leads to an oscillating oxygen partial pressur...

It has been proposed that 90% of American's diets are deficient in the trace essential mineral chromium. Several chromium(III) dietary supplements are currently available to alleviate this deficiency. We show here that the same pharmacokinetic models that have been used to quantitate absorption of chromium(III) in humans predict that ingested chromium(III) will accumulate and be retained in hum...

Lead chalcogenide nanostructures are good potential candidates for applications in multiexciton solar cells, infrared photodetectors, and electroluminescence devices. Here we report the synthesis and electrical measurements of hyperbranched PbSe nanowire networks. Hyperbranched PbSe nanowire networks are synthesized via a vapor-liquid-solid (VLS) mechanism. The branching is induced by continuou...

In this paper we make some general comments on the methods used for modelling glasses and use glassy GeSe2 as an example. We then emphasize recent work on As–Se glasses, including glassy As2Se3 and amorphous AsSe. The topology and electronic and vibrational properties of the models are discussed and with their use we infer the microscopic nature of the valence band x-ray photoemission (XPS) sig...

Toxic heavy metal pollution of water and soil is a major environmental concern for which conventional remediation approaches do not provide an appropriate solution. Phytoremediation, which involves removal of pollutants from water and soil through plants, is of low cost and environmentally friendly. In this study, the phytoremediation potential of Lemna minor for the uptake of Cr(VI) at the opt...