Analytical Chemistry Commons^™

Intra-Skeletal Variation In Stable Isotopes Through Non-Destructive Approaches: Applications Of The Patterns Of Skeletal Remodeling To Biological Anthropology, Armando Anzellini

Doctoral Dissertations

Stable isotope analysis is a well-established method in biological anthropology used to deliver data on residence, diet, and life history. Samples for these analyses are often collected from the diaphyses of long bones with an assumption of an expected rate of turnover between five and ten years, depending on the skeletal element. However, the biological foundations of this assumption are still uncertain, especially concerning the intra-skeletal and intra-element variation of isotopic signatures that may relate to patterns of remodeling. Exploring these gaps in intra-element isotopic variation requires fine-grained work using multiple bones from multiple individuals, but such work is limited …

Development Of Raman Spectroscopic Methods For Detection Of Molecules Indicating Life In Extraterrestrial Environments, Grace Sarabia

Doctoral Dissertations

Mineral analysis is of great importance to the understanding of the world around us and worlds beyond. Geology, chemistry, and environmental studies all benefit from characterization of the structure and properties of minerals. While various techniques have been applied towards the study of minerals, we propose that Raman spectroscopy is specifically suited for the detection and study of minerals under various conditions, including for terrestrial and space applications.

In our terrestrial studies, we explored the polymorphs of calcium carbonate within freshwater mollusk shell matrices with Raman spectroscopy. We found that aragonite was the main calcium carbonate polymorph present in the …

Analysis Of Primary Stripper Foils At The Spallation Neutron Source By An Electron Beam Foil Test Stand, Eric Paul Barrowclough

Doctoral Dissertations

Diamond films are used at the Spallation Neutron Source (SNS) as the primary charge exchange foils (i.e., stripper foils) of the accelerated 1 GeV (Gigaelectron volts) hydride ions. The most common type of film used is a nanocrystalline diamond film, typically 17 mm x 45 mm (millimeter) with an aerial density of 350 μg/cm² (microgram per square centimeter). The diamond film is deposited on a corrugated silicon substrate using plasma-assisted chemical vapor deposition. After the growth of the diamond film, 30 mm of the silicon substrate is etched away, leaving a freestanding diamond foil with a silicon handle that …