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Charge Transfer and Support Effects in Heterogeneous Catalysis

Description: The kinetic, electronic and spectroscopic properties of two‐dimensional oxide‐supported catalysts were investigated in order to understand the role of charge transfer in catalysis. Pt/TiO{sub 2} nanodiodes were fabricated and used as catalysts for hydrogen oxidation. During the reaction, the current through the diode, as well as its I‐V curve, were monitored, while gas chromatography was used to measure the reaction rate. The current and the turnover rate were found to have the same temperature… more
Date: December 21, 2011
Creator: Hervier, Antoine
Partner: UNT Libraries Government Documents Department
open access

GaAs Blocked-Impurity-Band Detectors for Far-Infrared Astronomy

Description: High-purity and doped GaAs films have been grown by Liquid-phase epitaxy (LPE) for development of a blocked impurity band (BIB) detector for far-infrared radiation. The film growth process developed has resulted in the capability to grow GaAs with a net active impurity concentration below 1 x 10{sup 13} cm{sup -3}, ideal for the blocking layer of the BIB detector. The growth of n-type LPE GaAs films with donor concentrations below the metal-insulator transition, as required for the absorbing la… more
Date: December 21, 2004
Creator: Cardozo, Benjamin Lewin
Partner: UNT Libraries Government Documents Department
open access

Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects

Description: Experimental and theoretical research conducted in two areas in the field of nuclear magnetic resonance (NMR) spectroscopy is presented: (1) studies of the coherent quantum-mechanical control of the angular momentum dynamics of quadrupolar (spin I > 1/2) nuclei and its application to the determination of molecular structure; and (2) applications of the long-range nuclear dipolar field to novel NMR detection methodologies.The dissertation is organized into six chapters. The first two chapters… more
Date: December 21, 2004
Creator: Urban, Jeffry Todd
Partner: UNT Libraries Government Documents Department
open access

Sum-frequency spectroscopic studies: I. Surface melting of ice, II. Surface alignment of polymers

Description: Surface vibrational spectroscopy via infrared-visible sum-frequency generation (SFG) has been established as a useful tool to study the structures of different kinds of surfaces and interfaces. This technique was used to study the (0001) face of hexagonal ice (Ih). SFG spectra in the O-H stretch frequency range were obtained at various sample temperatures. For the vapor(air)/ice interface, the degree of orientational order of the dangling OH bonds at the surface was measured as a function of te… more
Date: December 21, 2000
Creator: Wei, Xing
Partner: UNT Libraries Government Documents Department
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