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Mechanistic studies of the oxidations of hydrocarbons by manganese and ruthenium transition metal complexes
(2002)
The oxidation of hydrocarbon C-H and O-H bonds can occur by a variety of mechanisms. These include stepwise processes such as initial electron or proton transfer, or concerted mechanisms such as hydride transfer or hydrogen-atom abstraction. Hydrocarbons containing weak C-H and O-H bonds are oxidized by Mn(hfacac)3 (hfacac = ...
Regenerating the sampling interface of modular chemical sensing systems
(2002)
This dissertation describes modular chemical sensing systems (MCSS) and how the sampling interfaces of these systems can be regenerated. By regenerating the sampling interface, the reproducibility of the sensing system's measurements can be improved over traditional stationary sampling interfaces. The first modular chemical ...
Comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry with chemometric analysis
(2004)
Multidimensional separations, in particular Comprehensive Two-Dimensional Gas Chromatography (GC x GC), have proven to be powerful techniques that have found a niche in complex mixture analysis. Instruments of this type produce second-order data that is applicable to chemometric analysis. This combination of multidimensional ...
Analysis of CW-EPR spectra and the internal dynamics of DNA
(1996)
A new lineshape analysis program is developed to accurately extract the relaxation rate R$\sb2$ from CW-EPR spectra in the fast motion limit, taking into account instrumental broadening, saturation from R$\sb{\rm 1e}$, and $\sp$C isotope effects. The broadening effects of spin label concentration and oxygen concentration on ...
Dynamics and structures of linear and supercoiled DNAs
(1989)
A normal mode theory is developed for the Brownian dynamics of weakly bending rods with preaveraged hydrodynamic interactions. An expression is given for the mean squared angular displacement $$ of the $m\sp{th}$ bond-vector around the instantaneous x-axis (perpendicular to the end-to-end vector z). The normal mode theory is ...
The stable hydrogen isotopic composition of methane emitted from biomass burning and removed by oxic soils: application to the atmospheric methane budget
(1998)
The stable hydrogen isotopic composition (deltaD) of CH4 was developed for use as a constraint for the atmospheric CH4 budget by characterizing the deltaD of CH4 emitted from biomass burning and removed by oxic soils and the deltaD of atmospheric CH4 in tropospheric background air. These measurements were combined with ...
Theory guided design and molecular engineering of organic materials for enhanced second-order nonlinear optical properties
(2006)
The last two decades of research in the field of organic 2nd-order nonlinear optical (electro-optic) materials has led to a deeper understanding of salient fundamental processes. Detailed definitions of critical structure-property relationships have led to the realization of new materials displaying dramatically enhanced ...
Structural analysis of amylin and its analogs by NMR spectroscopy
(1999)
Amylin is a 37 residue peptide hormone, which is believed to be involved in metabolic diseases, such as diabetes. The studies presented in this dissertation were initially carried out on rat and human amylin, and later concentrated on pramlintide, an agonist of human amylin. The conformational preferences of these peptides ...
Reactive and soft landing of polyatomic gas-phase ions on plasma-treated metal surfaces
(2006)
Non-destructive physical isolation of ions from the gas phase with preservation of their structure is referred to as ion soft landing. The presented dissertation describes in-situ plasma oxidized dry metal surfaces as novel and advantageous collection targets (plates) for soft landing experiments. A new term, reactive landing, ...