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Age-Associated Changes In The Kinetics Of Ventilation And Pulmonary Gas Exchange, Mark Anthony Babcock
Age-Associated Changes In The Kinetics Of Ventilation And Pulmonary Gas Exchange, Mark Anthony Babcock
Digitized Theses
The purpose of these studies was to examine ageing effects on the dynamics of pulmonary gas exchange and ventilation during the transition from light to moderate work. In the first study maximal oxygen uptake (VO{dollar}\sb2{dollar}max), ventilation threshold (VeT), the time constant for VO{dollar}\sb2{dollar} ({dollar}\tau\sp\prime{dollar}VO{dollar}\sb2{dollar}), and efficiency were determined from a ramp forcing test in eighty-three males aged 30 to 84y. The results showed a decline in VO{dollar}\sb2{dollar}max with age of {dollar}-{dollar}0.037 1{dollar}\cdot{dollar}min{dollar}\sp{lcub}-1{rcub}{dollar} per year. The VeT also declined with age but at one-third the rate of loss of the VO{dollar}\sb2{dollar}max. The {dollar}\tau\sp\prime{dollar}VO{dollar}\sb2{dollar} increased with age; the older group (60+y) had …
Laser-Molecule Interactions And The Effects Of Permanent Dipoles, Anne E. Kondo
Laser-Molecule Interactions And The Effects Of Permanent Dipoles, Anne E. Kondo
Digitized Theses
The spectral and dynamic effects associated with a non-zero difference, d, between the permanent dipole moments of two molecular states involved in a transition, are investigated for a variety of electromagnetic field-molecule interactions. Both analytical and exact numerical techniques are used to solve the time-dependent Schrodinger equation and to obtain the temporal populations of the molecular states and the associated absorption spectra, for molecular interactions with a Gaussian pulsed, or one or two continuous wave (CW), laser(s).;Analytical rotating wave approximation results are derived for a single CW laser interacting with a two-level d {dollar}\ne{dollar} 0 molecule with an excited state …
The Photophysics Of Polycyclic Aromatic Hydrocarbons Adsorbed On Silica Gel Surfaces: A Lifetime Distribution Analysis Approach, Yuan-Sheng Liu
The Photophysics Of Polycyclic Aromatic Hydrocarbons Adsorbed On Silica Gel Surfaces: A Lifetime Distribution Analysis Approach, Yuan-Sheng Liu
Digitized Theses
The relaxation process of excited molecules, in homogeneous systems, is routinely studied through the measurements of fluorescence lifetimes and fluorescence quantum yields. From these data, the radiative decay rate, and hence the non-radiative decay rate, can be easily derived. Effort has been made, in the present work, to conduct such a fundamental study with molecules adsorbed on silica gel surfaces.;The photophysics of six polycyclic aromatic hydrocarbons (PAH), comprising phenanthrene, chrysene, pyrene, perylene, benzoperylene and coronene, adsorbed on variously dehydroxylated silica gel surfaces, has been investigated in this work. It has been observed that the fluorescence lifetimes of these adsorbed PAHs …
Fundamental Studies Of Interactions Of Water With The Nickel(110) Surface, Brian William Callen
Fundamental Studies Of Interactions Of Water With The Nickel(110) Surface, Brian William Callen
Digitized Theses
The adsorption of water on Ni(110) has been studied by electron stimulated desorption ion angular distributions (ESDIAD), Fourier transform infrared-reflection absorption spectroscopy (FTIR-RAS), low energy electron diffraction (LEED), nuclear reaction analysis (NRA), and work function measurements ({dollar}\Delta\Phi{dollar}). The major findings in this study are: The saturation coverage of the first chemisorbed layer of water is 0.5 water molecules per surface Ni atom or 0.5 ML (1 ML = monolayer = 1.14 {dollar}\times{dollar} 10{dollar}\sp{lcub}15{rcub}{dollar} molecules cm{dollar}\sp{lcub}-2{rcub}{dollar}). The first chemisorbed layer exhibits c(2 x 2) symmetry, and is bonded to the surface monomerically (no evidence of intermolecular hydrogen bonding) with the plane …
Investigation Of Naphthacene Mobility On Silica, David Wayne Bjarneson
Investigation Of Naphthacene Mobility On Silica, David Wayne Bjarneson
Digitized Theses
Photophysical and photochemical examinations of polycyclic aromatic hydrocarbons adsorbed on metal oxide surfaces provide indirect evidence for the mobility of these species. We employ Fluorescence Photobleaching Recovery (FPR) to directly measure the mobility of naphthacene on various silica gel surfaces at low coverages. On normal phase silica, the rate of diffusion is found to be invariant of the surface treatment. The diffusion coefficient is constant at 2.5 {dollar}\times{dollar} 10{dollar}\sp{lcub}-10{rcub}{dollar} cm{dollar}\sp2{dollar} s{dollar}\sp{lcub}-1{rcub}{dollar}, but the mobile fraction shows a pronounced dependence on surface treatment. These results indicate that the mobility of the same population of naphthacene is being measured in each case, …
Solvent Dependence Of Photoinduced Intramolecular Electron Transfer, Jing-Yao Liu
Solvent Dependence Of Photoinduced Intramolecular Electron Transfer, Jing-Yao Liu
Digitized Theses
This work is a study of the solvent and temperature dependence of photoinduced intramolecular electron transfer (ET). The molecule containing a porphyrin and a quinone linked by a phenylalanine amino acid residue was synthesized. Excitation of this molecule (PPAQ) causes electrons to be transferred from the porphyrin to the quinone entity. The ET rate constants were measured by comparing the porphyrin fluorescence lifetime with or without the possibility of ET.;The ET rate constants of PPAQ were measured for several solvents and compared with data of other similar porphyrin-quinone linked molecules. A temperature dependence of ET rate constants study was also …