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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.
11

Direct mass measurements on exotic nuclei with SHIPTRAP and ISOLTRAP

Dilling, Jens. Unknown Date (has links) (PDF)
University, Diss., 2001--Heidelberg. / Parallelt.: Direkte Massenmessungen an exotischen Kernen mit SHIPTRAP und ISOLTRAP.
12

Doppelresonanzmessungen an in einer Penningfalle gespeicherten Europium-Ionen zur Bestimmung des Kern-g-Faktors

Trapp, Sascha. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2001--Mainz.
13

Konzeption eines kryogenen Penningfallenaufbaus für SHIPTRAP und Massenbestimmungen von Radionukliden um den Z=82-Schalenabschluss an ISOLTRAP

Weber, Christine. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2004--Heidelberg.
14

Examining the Effects of Penning on Juvenile Eastern Box Turtles (Terrapene carolina carolina)

Frederick, Nicolas 02 December 2009 (has links)
Box turtle (Terrapene carolina) populations have been declining over the last several decades, and one major cause is increasing urbanization. As a result of habitat fragmentation, wildlife managers are frequently turning to new and alternative management strategies. Traditional box turtle management has included relocation, which has been met with limited success. This study aims to combine these strategies with another less-studied one: forcing turtles to overwinter on site by penning them in an outdoor enclosure. Two sets of juvenile box turtles were released at the Virginia Commonwealth University Rice Center: one penned on site in a pen for one year, the other allowed to move freely. Our objective was to compare a variety of factors between these two groups to see if penning was as effective as traditional approaches. Movement and location patterns were tracked using radio transmitters for two years and analyzed using GPS technology. Body condition and health status of all turtles were measured and compared over time as well. Finally, a life history model was developed to determine the effectiveness of management programs. While the penning treatment significantly reduced activity areas, it appears that all juvenile turtles had high site fidelity (87.5%) regardless of treatment. The eastern box turtle seems to be a prime candidate for penning used in conjunction with other management options.
15

Investigating the astrophysical rp-process through atomic mass measurements

Clark, Jason A 13 October 2005 (has links)
The Canadian Penning Trap (CPT) mass spectrometer at the Argonne National Laboratory makes precise mass measurements of both stable and unstable nuclides. To date, more than 60 radioactive isotopes having half-lives as short as one second have been measured with the CPT with a mass precision approaching 10 ppb. This thesis will present measurements made of nuclides along the rp-process path, which describes a process resulting from a series of rapid proton-capture reactions in an astrophysical environment. One possible site for the rp-process mechanism is an x-ray burst which results from the rapid accretion of hydrogen and helium from one star onto the surface of its neutron star binary companion. Mass measurements are required as key inputs to network calculations used to describe the rp-process in terms of the abundances of the nuclides produced, the light-curve profile of the x-ray bursts, and the energy produced. This thesis will describe the CPT apparatus, explain the method used to make precise mass measurements, and present the masses of the "waiting-point" nuclides <sup>68</sup>Se and <sup>64</sup>Ge. The mass measurement results, when used in x-ray burst models, confirm both <sup>68</sup>Se and <sup>64</sup>Ge as waiting-point nuclides which delay the rp-process by approximately 30 s and 7 s respectively. / October 2005
16

Investigating the astrophysical rp-process through atomic mass measurements

Clark, Jason A 13 October 2005 (has links)
The Canadian Penning Trap (CPT) mass spectrometer at the Argonne National Laboratory makes precise mass measurements of both stable and unstable nuclides. To date, more than 60 radioactive isotopes having half-lives as short as one second have been measured with the CPT with a mass precision approaching 10 ppb. This thesis will present measurements made of nuclides along the rp-process path, which describes a process resulting from a series of rapid proton-capture reactions in an astrophysical environment. One possible site for the rp-process mechanism is an x-ray burst which results from the rapid accretion of hydrogen and helium from one star onto the surface of its neutron star binary companion. Mass measurements are required as key inputs to network calculations used to describe the rp-process in terms of the abundances of the nuclides produced, the light-curve profile of the x-ray bursts, and the energy produced. This thesis will describe the CPT apparatus, explain the method used to make precise mass measurements, and present the masses of the "waiting-point" nuclides <sup>68</sup>Se and <sup>64</sup>Ge. The mass measurement results, when used in x-ray burst models, confirm both <sup>68</sup>Se and <sup>64</sup>Ge as waiting-point nuclides which delay the rp-process by approximately 30 s and 7 s respectively.
17

Investigating the astrophysical rp-process through atomic mass measurements

Clark, Jason A 13 October 2005 (has links)
The Canadian Penning Trap (CPT) mass spectrometer at the Argonne National Laboratory makes precise mass measurements of both stable and unstable nuclides. To date, more than 60 radioactive isotopes having half-lives as short as one second have been measured with the CPT with a mass precision approaching 10 ppb. This thesis will present measurements made of nuclides along the rp-process path, which describes a process resulting from a series of rapid proton-capture reactions in an astrophysical environment. One possible site for the rp-process mechanism is an x-ray burst which results from the rapid accretion of hydrogen and helium from one star onto the surface of its neutron star binary companion. Mass measurements are required as key inputs to network calculations used to describe the rp-process in terms of the abundances of the nuclides produced, the light-curve profile of the x-ray bursts, and the energy produced. This thesis will describe the CPT apparatus, explain the method used to make precise mass measurements, and present the masses of the "waiting-point" nuclides <sup>68</sup>Se and <sup>64</sup>Ge. The mass measurement results, when used in x-ray burst models, confirm both <sup>68</sup>Se and <sup>64</sup>Ge as waiting-point nuclides which delay the rp-process by approximately 30 s and 7 s respectively.
18

Tools for a precise tritium to helium-3 mass comparison /

Pinegar, David Brian, January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (p. 210-216).
19

Avaliação da tensão residual em alumínio 7050 conformado pelo processo PEEN forming / Residual stress evaluation and curvature behaviour of aluminium 7050 PEEN forming processed

OLIVEIRA, RENE R. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:22Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:31Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
20

Avaliação da tensão residual em alumínio 7050 conformado pelo processo PEEN forming / Residual stress evaluation and curvature behaviour of aluminium 7050 PEEN forming processed

OLIVEIRA, RENE R. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:22Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:31Z (GMT). No. of bitstreams: 0 / O tratamento superficial de shot peening tem por objetivo aumentar a resistência à fadiga sendo comparada pelas medidas de tensão residual. O processo peen forming é uma variante do processo shot peening onde se obtém uma curvatura na placa produzida pelo jateamento das esferas através da compressão dos grãos localizados próximos à superfície. Foi estudado neste trabalho a influência dos parâmetros pressão e tamanho de granalha, utilizado no processo de peen forming, no perfil de tensão residual e no raio de curvatura em amostras de alumínio 7050. A avaliação do perfil de tensão de residual foi efetuada por difração de raios-x utilizando o método de sen2 . Os resultados mostram que a formação da altura do arco de curvatura é proporcional a pressão de jateamento e ao tamanho das esferas e inversamente proporcional a espessura da amostra, e que o fator de concentração de tensões é maior para amostras jateadas com menores esferas. Na seção final deste trabalho apresenta um estudo complementar sobre microdeformação e tamanho médio de cristalito, podendo avaliar o perfil das amostras após jateamento. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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