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Aspects Of Sims Matrix Effects In Aluminum-Gallium - Arsenide, William Harvey Robinson
Aspects Of Sims Matrix Effects In Aluminum-Gallium - Arsenide, William Harvey Robinson
Digitized Theses
In secondary ion mass spectrometry (SIMS) the detected ion count rate must be corrected for differences in matrix when depth profiling semiconductor samples with layered structures of different composition. Few published studies of the matrix effect exist and those that have studied the matrices give widely differing factors. The situation is further complicated by secondary ion molecular interferences which can completely mask the ion signal of interest. These problems are examined in this thesis.;The depth distribution of ion implanted samples of {dollar}\sp{lcub}28{rcub}{dollar}Si and {dollar}\sp{lcub}52{rcub}{dollar}Cr in Al{dollar}\sb{lcub}\rm X{rcub}{dollar}Ga{dollar}\sb{lcub}\rm 1-X{rcub}{dollar}As and X equal to 0, 0.066, 0.21 and 0.40 for energies of …
Diffusion In Strong And Weak Mixed Electrolyte Solutions, Robert Alexander Noulty
Diffusion In Strong And Weak Mixed Electrolyte Solutions, Robert Alexander Noulty
Digitized Theses
Binary diffusion coefficients of dilute aqueous lithium, sodium and potassium hydroxides have been determined at 25{dollar}\sp\circ{dollar}C by a simplified verison of Harned's conductimetric technique. The large difference in mobility between OH{dollar}\sp-{dollar} and the cations leads to an electrophoretic effect which reduces the rate of diffusion. Measured and predicted diffusion coefficients are in excellent agreement. Diffusion-derived activity coefficients are compared with activity data obtained from emf methods.;A matrix diagonalization procedure has been developed to determine multicomponent diffusion coefficients. If linear combinations of data from multicomponent diffusion experiments with different initial concentration gradients are analyzed as simple binary data, certain combinations can …
Characterization Of The Integrative Precursor Protein-Dna Complex Of Bacteriophage Mu, Gregory Brian Gloor
Characterization Of The Integrative Precursor Protein-Dna Complex Of Bacteriophage Mu, Gregory Brian Gloor
Digitized Theses
Bacteriophage Mu integrates and replicates its genome via DNA transposition. Mu transposition during integration is non-replicative (conservative) and generates simple insertions. Transposition during the lytic cycle is replicative and amplifies the Mu genome by cointegrate production. Mu therefore, must choose between these two pathways. Infecting Mu-DNA is found associated with a coinjected, 64-kDa virion protein bound noncovalently to its ends. Characterization of the protein-DNA complex is reported here.;Antiserum was prepared against the virion 64-kDa protein and used to probe an expression library of cloned Mu DNA sequences. The Mu {dollar}N{dollar} gene was mapped to the overproducing clones by physical and …
Defect Energies And Entropies From Computer Simulation And Ionic Conductivity Measurements, Irene Elizabeth Hooton
Defect Energies And Entropies From Computer Simulation And Ionic Conductivity Measurements, Irene Elizabeth Hooton
Digitized Theses
Ionic conductivity measurements have been made on pure and strontium- and sulphide-doped sodium chloride and the data analysed by means of a non-linear least squares fitting routine. The purpose of this investigation was two-fold. First, the question as to what types of defects occur in NaCl needed to be resolved. Recent work on KCl indicated that a small concentration of Frenkel defects was present on both sub-lattices in addition to Schottky defects, which have been assumed to predominate in alkali halides. Secondly, a wide variety of values for the anion vacancy migration energy have been given in the literature and …
Ligand Effects In Binuclear And Trinuclear Platinum Diphosphine Complexes, Ian Ronald Jobe
Ligand Effects In Binuclear And Trinuclear Platinum Diphosphine Complexes, Ian Ronald Jobe
Digitized Theses
This is a study into the steric and electronic factors governing the synthesis and reactivity of some platinum diphosphine complexes. We report the preparation of a number of new diphosphine ligands: The ethyl and methyl derivatives of (RO){dollar}\sb2{dollar}PCH{dollar}\sb2{dollar}P(OR){dollar}\sb2{dollar} and (Me{dollar}\sb{lcub}\rm n{rcub}{dollar}C{dollar}\sb5{dollar}H{dollar}\sb{lcub}\rm 5-n{rcub})\sb2{dollar}PCH{dollar}\sb2{dollar}P(C{dollar}\sb6{dollar}H{dollar}\sb{lcub}\rm 5-n{rcub}{dollar}Me{dollar}\sb{lcub}\rm n{rcub})\sb2{dollar}, where n = 1 ({dollar}p, m{dollar} and {dollar}o{dollar}-tolyl), 2 ({dollar}m{dollar}-xylyl) and 3 (mesityl).;The preparation and characterization of some platinum(II) complexes, (PtX{dollar}\sb2{dollar}(R{dollar}\sb2{dollar}PCH{dollar}\sb2{dollar}PR{dollar}\sb2)\rbrack\sb{lcub}\rm n{rcub}{dollar}, where X = halide or methyl, have shown how the bulk of the ligand, R{dollar}\sb2{dollar}PCH{dollar}\sb2{dollar}PR{dollar}\sb2{dollar}, can have dramatic effects upon the nuclearity, n, and upon the conformations adopted by the Pt{dollar}\sb2{dollar}P{dollar}\sb4{dollar}C{dollar}\sb2{dollar} rings in binuclear …
Metabolic Modulation Of Mammalian Dna Excision Repair, Timothy John Schrader
Metabolic Modulation Of Mammalian Dna Excision Repair, Timothy John Schrader
Digitized Theses
The influence of a variety of metabolic factors on DNA excision repair was examined in studies involving measurements of damaged base removal, repair replication, and size of the resulting resynthesized regions or repair patches.;First, ultraviolet light (UVL)- and dimethylsulfate (DMS)-induced excision repair was examined in quiescent and lectin-stimulated bovine lymphocytes. Upon mitogenic stimulation, UVL-induced repair increased by a factor of 2 to 3, and reached this maximum 2 days before the onset of DNA replication. However, DMS-induced repair increased sevenfold in parallel with DNA replication. Repair patch sizes were smaller for DMS-induced damage reflecting patches of 7 nucleotides in quiescent …
Complexes Of Platinum Containing Sulphide And Diphosphine Ligands, Nasim Hadj-Bagheri
Complexes Of Platinum Containing Sulphide And Diphosphine Ligands, Nasim Hadj-Bagheri
Digitized Theses
This thesis describes the chemistry of some homonuclear and mixed-metal complexes of platinum with sulphide and diphosphine ligands.; (PtPh{dollar}\sb2{dollar}({dollar}\eta\sp1{dollar}-dmpm){dollar}\sb2{dollar}); dmpm = bis(dimethylphosphino)methane, is formed by the facile reaction of a diaryl platinum species with excess ligand. Synthesis of symmetric and asymmetric binuclear platinum complexes is achieved through the bonding of the uncoordinated phosphines to a second platinum centre. Oxidative addition reactions of these dimers are studied.; (Pt{dollar}\sb2{dollar}({dollar}\mu{dollar}-dppm){dollar}\sb3{dollar}); dppm = bis(diphenylphosphine)methane, reacts with carbonyl sulphide to yield (Pt{dollar}\sb2{dollar}({dollar}\mu{dollar}-S)({dollar}\mu{dollar}-dppm)({dollar}\eta\sp1{dollar}-dppm){dollar}\sb2{dollar}). This complex is used as a precursor in construction of trinuclear clusters. Coordination to a third centre can be achieved through the mono-coordinated …
Photophysical And Photoelectrochemical Studies Of A Langmuir-Blodgett Film Of A Porphyrin Dye, Harold Alfred Dick
Photophysical And Photoelectrochemical Studies Of A Langmuir-Blodgett Film Of A Porphyrin Dye, Harold Alfred Dick
Digitized Theses
Time-resolved fluorescence lifetime measurements of 5-(4-carboxyphenyl)-10,15,20-tritolylporphyrin (TTPa) with dioleoylphosphatidylcholine (DOPC) in mixed Langmuir-Blodgett (LB) films on quartz slides were performed at two different laboratories in an attempt to create a standard system for future monolayer fluorescence work. TTPa in the mixed LB film exhibited a simpler and longer decay profile than for a pure TTPa monolayer. At a DOPC/TTPa molar ratio of 50:1, the decay consisted primarily of one lifetime of 10.7 {dollar}\pm{dollar} 0.2 ns. Simplification of the decay and lengthening of the lifetime was attributed to reduction of TTPa aggregate formation in the film. This effect is also seen …
Effects Of Permanent Dipoles And Static Fields On Molecular Spectra, Mary Ann Kmetic
Effects Of Permanent Dipoles And Static Fields On Molecular Spectra, Mary Ann Kmetic
Digitized Theses
An analytic expression for the absorption spectra of a two-level molecule or atom is derived, within the rotating wave approximation (RWA), which includes the effects of permanent dipole moments and static electric fields. The derivation is for the interaction of the system with a plane-polarized sinusoidal electromagnetic field (EMF) in the semi-classical electric dipole approximation. The RWA resonance profile, and a series of exactly calculated two-level model spectra, are used to investigate some single- and multi-photon spectral effects due to permanent dipoles and static fields, relative to the atomic problem (no permanent dipoles). These effects include the occurrence of even …