Native point defects, defect complexes, and oxygen impurities in BaCuChF were studied using density
functional theory calculations, self-consistent thermodynamic simulations, and various experimental techniques.
Unintentional p-type conductivity in BaCuChF is explained by the presence of copper vacancies with
transition levels in the valence band. These acceptor-like defects are partially compensated...
Climate models predict a gradual weakening of the North Atlantic meridional overturning circulation (MOC) during the twenty-first century due to increasing levels of greenhouse gas concentrations in the atmosphere. Using an ensemble of 16 different coupled climate models performed for the Fourth Assessment Report (AR4) of the Intergovernmental Panel on...
Environmental concerns about seafood consumption generally are associated with the status of target stocks as well as bycatch and/or habitat issues. The more recent concept of "food miles" hails from terrestrial food production, and focuses on "consuming locally" in an effort to reduce the carbon footprint of a consumer's diet....
The main contributions of this thesis are the development and
application of four computationally efficient solutions for
least-squares-based (LS-based) minimum variance spectral estimation
(MVSE). They are: (1) fast computational solution for the 1-D
covariance LS-based MVSE, (2) fast computational solution for the
1-D modified covariance LS-based MVSE, (3) fast computational...
BaCuChF (Ch = S, Se, Te) materials are chalcogen-based transparent conductors with wide optical band gaps (2.9 – 3.5 eV) and a high concentration of free holes (10¹⁸ – 10²⁰ cm⁻³) caused by the presence of copper vacancies. Chalcogen vacancies compensate copper vacancies in these materials, setting the Fermi level...
In this dissertation we develop mathematical treatment for two important applications: (i) evolution of methane in coalbeds with the associated phenomena of adsorption, and (ii) formation of methane hydrates in seabed. We use simplified models for (i) and (ii) since we are more interested in qualitative properties of the solutions...
Total electronic energies are calculated numerically for
free and singly-ionized He, Li, C, and Ne atoms using density
functional theory. Immersion energies are calculated for a single
C impurity atom embedded or absorbed into a charge-neutral system
composed of a free-electron gas with uniform positive background,
also called 'jellium'. Nonspherical...
Anthropogenic releases of trace gases into the
atmosphere are causing a decrease in stratospheric ozone
concentrations and a subsequent increase in solar
ultraviolet-B (UV-B)(280-320 nm) radiation reaching the
earth's surface. The objective of this study was to
determine the acute effects of enhanced UV-B radiation on
the primary production of...
Greater sage-grouse (Centrocercus urophasianus: hereafter sage-grouse) abundance and distribution in North America has declined over the last century. Many factors have contributed to this decline, including habitat loss and fragmentation from human development with an associated potential for increased predation. While human development has been connected to lower sage-grouse demographic...
The effect of pyridoxine (PN) supplementation on lymphocyte
responsiveness was investigated in 15 elderly volunteers (aged
65-81 years) by measuring lymphocyte proliferation to T and B cell
mitogens, lymphocyte subpopulations with monoclonal antibodies
(T3, T4, T8) and plasma pyridoxal 5'-phosphate (PLP) concentration
at pre-supplementation and after 1 and 2 months...