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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Determinacao de funcoes de distribuicao de energia para microdosimetria de fotons e neutrons

TODO, ALBERTO S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:15Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:20Z (GMT). No. of bitstreams: 1 03762.pdf: 3113511 bytes, checksum: 2b2dbeb97f197c8a26fd6f461c266461 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
2

Determinacao de funcoes de distribuicao de energia para microdosimetria de fotons e neutrons

TODO, ALBERTO S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:36:15Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:20Z (GMT). No. of bitstreams: 1 03762.pdf: 3113511 bytes, checksum: 2b2dbeb97f197c8a26fd6f461c266461 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
3

Decomposing kinetic energy along Line P in the Pacific Ocean

Wang, Manman 18 August 2016 (has links)
The upper ocean is host to overlapping vortical and internal waves dynamics over the submesoscales (10-100km), both of which are poorly represented in eddy-resolving ocean models. We analyze upper-ocean (0-200 m) horizontal-wavenumber spectra along Line P in the North Pacific subpolar gyre from shipboard ADCP measurements in February and June (2013-2015), and compare them to spectra from a 1/36th degree numerical simulation output. At scales between 10 and 100 km, the ADCP along-track (Cv) and across-track (Cv) kinetic energy spectra approximately follow power laws of k-2 and have a ratio R = Cv/Cu - 1. For purely non-divergent motions, the order of the power law and R should be the same, so divergent motions are evident. A Helmholtz decomposition estimates the fraction total kinetic energy that is contributed by internal-wave and vortex components. Vortex components follow a power law of k-2 with ratio R-2, consistent with predictions for a non-divergent flow, while internal waves are mostly consistent with the Garrett and Munk internal wave model. There are modest seasonal changes; vortical motions are slightly stronger in February than in June, whereas the amplitudes of the internal wave component increases in June. Depth variability of non-divergent vortical flows shows that at low wave-numbers energy decreases and that the kinetic energy spectra are bluer with depth, inconsistent with predictions from surface quasi-geostrophic theory of redder spectra with depth. Conversely, in the simulation the depth variability of the decomposed vortex components is in agreement with predictions of surface quasi-geostrophic theory. The simulations had very weak internal waves fields. / Graduate / 0415 / manmanw@uvic.ca
4

The Vibrational and Electronic Spectra of Cyanoacetylene

Job, Variamparambil Anthony 10 1900 (has links)
<p> The infrared and Raman spectra of cyanoacetylene and deuterocyanoacetylene have been measured and ground state vibrational energy levels have been obtained from the analysis of these spectra.</p> <p> Two band systems have been identified in the absorption spectrum of cyanoacetylene in the region 2700 - 2000 Å. Vibrational and rotational analyses have shown that the lower energy transition involves a non-linear planar upper state having A" symmetry. Approximate geometry of the molecule in the A" state has been determined.</p> <p> In the second electronic transition the upper state has been found to be linear. A vibrational analysis has been obtained on the basis of an electronically forbidden 1Δ<--- 1 Σ+ or 1 Σ- <--- 1 Σ+ transition, which is made allowed by vibronic interactions.</p> / Thesis / Doctor of Philosophy (PhD)
5

A study of plasma-related ion-surface interactions

Gillen, David R. January 1999 (has links)
No description available.
6

Hadronic fragmentation studies in ep scattering at HERA

Donovan, Keith Thomas January 1998 (has links)
No description available.
7

Structure of free radicals

Critchley, Andrew Duncan James January 2001 (has links)
No description available.
8

Microanalysis for Oxygen Fugacity by Secondary Ion Mass Spectrometry

January 2019 (has links)
abstract: Oxygen fugacity (ƒO2) is a thermodynamic variable used to represent the redox state of a material or a system. It is equivalent to the partial pressure of oxygen in a particular environment corrected for the non-ideal behavior of the gas. ƒO2 is often used to indicate the potential for iron to occur in a more oxidized or reduced state at a particular temperature and pressure in a natural system. Secondary ion mass spectrometry (SIMS) is a powerful analytical instrument that can be used to analyze elemental and isotopic compositional information about microscopic features within solid materials. SIMS analyses of the secondary ion energy distribution of semi-pure metals demonstrate that the energy spectrum of individual mass lines can provide information about alterations in its surface environment. The application of high-resolution (see Appendix C) energy spectrum calibrations to natural ilmenite led to the investigation of zirconium (90Zr+) and niobium (93Nb+) as potential indicators of sample ƒO2. Energy spectrum measurements were performed on an array of ilmenite crystals from the earth’s upper mantle retrieved from kimberlites and from a reduced meteorite. In all studied materials, variability in the peak shape and width of the energy spectra has been correlated with inferred sample ƒO2. The best descriptor of this relationship is the full-width at half-maximum (FWHM; see Appendix C) of the energy spectra for each sample. It has been estimated that a 1eV change in the FWHM of 93Nb+ energy spectra is roughly equivalent to 1 log unit ƒO2. Simple estimates of precision suggest the FWHM values can be trusted to  1eV and sample ƒO2 can be predicted to ±1 log unit, assuming the temperature of formation is known. The work of this thesis also explores the applicability of this technique beyond analysis of semi-pure metals and ilmenite crystals from kimberlites. This technique was applied to titanium oxides experimentally formed at known ƒO2 as well as an ilmenite crystal that showed compositional variations across the grain (i.e., core to rim chemical variations). Analyses of titanium oxides formed at known ƒO2 agree with the estimation that 1 eV change in the FWHM of 93Nb+ is equivalent to ~1 log unit ƒO2 (in all cases but one); this is also true for analyses of a natural ilmenite crystal with compositional variations across the grain. / Dissertation/Thesis / Masters Thesis Geological Sciences 2019
9

Characterisation of intermixed quantum well material by measurements of spontaneous emission

Blay, Claire January 2000 (has links)
No description available.
10

Investigations of electropositive and electronegative RF discharges

Bryant, Paul M. January 2000 (has links)
No description available.

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