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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.
31

Single-photon multiple ionization processes studied by electron coincidence spectroscopy

Linusson, Per January 2013 (has links)
This thesis is based on studies of multiple ionization of atoms and molecules induced by the absorption of a single photon. For the experimental investigations a time-of-flight magnetic bottle spectrometer has been used to detect the emitted electrons in coincidence. The method of coincidence time-of-flight spectroscopy and the experimental setup used is described. Experimental and theoretical results on molecular double core holes (DCHs) and multiple ionization of atoms are presented. Molecular DCHs are of considerable interest, as their chemical shifts are predicted to be more sensitive than their single core hole counterparts. Using CH4 and NH3 as examples, it is shown that molecules with two vacancies in the innermost shell can be studied using synchrotron light in combination with our coincidence technique. The chemical shifts of S 2p DCHs are investigated for the molecules CS2, H2S and SO2 and the influence of relaxation effects on the shifts are estimated. In the studies of atoms, the main focus is on the processes leading to double and higher degrees of ionization, and the final state populations. In cadmium double photoionization in the photon energy region 40-200 eV occurs mainly by indirect ionization via valence ionized satellite states and through Coster-Kronig decay of inner shell hole states. In valence-valence ionization of krypton by 88 eV photons both direct and indirect ionization processes are found to be important. For the indirect pathways strong final state selectivity in the autoionization decays of the intermediate states is observed. Triple ionization of krypton via intermediate core-valence doubly ionized states is investigated. The intermediate states are observed in the energy region 120-125 eV, and their decay to states of the triply charged ion is mapped. Experimental and theoretical results on the formation of 2p double hole states in argon are presented. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>
32

An Empirical Approach to Understanding the Relationship Between Recombination and Fitness

Tedman-Aucoin, Katherine 26 February 2009 (has links)
The persistence of sex is a recurrent conundrum in evolutionary biology because sex is costly. These costs may be accounted for by looking at the outcome of sex, namely that sex causes genetic mixing. Recombination is one of the processes by which sex causes genetic mixing; determining when recombination is advantageous may alleviate some of the costs of sex. The advantages of recombination are in the effects of recombination and the influences thereupon. The first experiment focuses on the effects of recombination on the mean fitness and variance in fitness. A second experiment examines the influences on recombination by addressing whether recombination is a general response to poor condition. Specifically, the impact on recombination rate of genotypes with variable fitness is investigated. Differing fitness effects are not correlated to recombination rates. Conversely, coincidence, a recombination related trait, is positively correlated with fitness.
33

An Empirical Approach to Understanding the Relationship Between Recombination and Fitness

Tedman-Aucoin, Katherine 26 February 2009 (has links)
The persistence of sex is a recurrent conundrum in evolutionary biology because sex is costly. These costs may be accounted for by looking at the outcome of sex, namely that sex causes genetic mixing. Recombination is one of the processes by which sex causes genetic mixing; determining when recombination is advantageous may alleviate some of the costs of sex. The advantages of recombination are in the effects of recombination and the influences thereupon. The first experiment focuses on the effects of recombination on the mean fitness and variance in fitness. A second experiment examines the influences on recombination by addressing whether recombination is a general response to poor condition. Specifically, the impact on recombination rate of genotypes with variable fitness is investigated. Differing fitness effects are not correlated to recombination rates. Conversely, coincidence, a recombination related trait, is positively correlated with fitness.
34

LEGAL ANALYSIS OF NATIONAL ADMINISTRATION FOR MEDICAL PROFESSIONS

Lin, Syuan-You 10 August 2004 (has links)
Illness is the painful and uncomfortable body state. It would endanger the healthy and even determine the life. People who were attack by disease could not perform in the role of socialization, and they would become the encumbrance of the healthy people. Therefore people develop the strategy which is research the medical therapy for counteract disease. After time the medical therapy get progress and become the medical system. The arrangement of medical resources, organization of medical supply and service, and efficiently medical management are the important fundamental elements of the medical system. According to protect public interest and constitutional right of people, the nation should administrate the medical system because of it is related to maintenance of social order, improvement of people health and life. The nation administrate medical matters by authorize medical self-administration, legislative administration, Executive administration and justice administration, in consideration of the medical professional self control deficiency. When there is coincidence between the administrative methods or means that is dealt with the principles as fallow: ¡§neb is in idem¡¨ , ¡§give a heavier punishment¡¨ or the criminal penalty is superior. The methods of remedy include the amendment, the referendum, administrative appeal, administrative produce, asking for state liability, the inner approach of medical autonomy. This study focus on nation administrate the medical system and the research scope involve: the medical worker; the medical institute (the hospital), the publish health (the control of infectious diseases, e.g. SARS ) , the medical advertisement and the medical waste material. The purpose of this study is which clarify and find out the advantage and disadvantage of the national administration of medical system through analysis overall the administration of medical system at present.
35

Medida absoluta da taxa de desintegracao e da probabilidade de emissao gama do sup[42]K

MOREIRA, DENISE S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:15Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:24Z (GMT). No. of bitstreams: 1 06884.pdf: 3958157 bytes, checksum: d230858464baf1ab2ee2867cf97407e4 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
36

Sistema de coincidencia para medida absoluta de atividade de radionuclideos empregando cintilador liquido

PUGLIESI, REYNALDO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:30:07Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:23Z (GMT). No. of bitstreams: 1 00384.pdf: 931217 bytes, checksum: 170cd2f3408ad5e430165e620436b412 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
37

Niveis do sup72Ge populados pelo decaimento beta sup(-) do sup72Ga

MEDEIROS, JOSE A.G. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:38:36Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:09Z (GMT). No. of bitstreams: 1 05834.pdf: 6637746 bytes, checksum: eac3b2442d4b06b5a8e3a4c9f46f1f9e (MD5) / Dissertacao (Mestrado) - IPEN / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
38

Medida absoluta da taxa de desintegracao e da probabilidade de emissao gama do sup[42]K

MOREIRA, DENISE S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:15Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:24Z (GMT). No. of bitstreams: 1 06884.pdf: 3958157 bytes, checksum: d230858464baf1ab2ee2867cf97407e4 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
39

Sistema de coincidencia para medida absoluta de atividade de radionuclideos empregando cintilador liquido

PUGLIESI, REYNALDO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:30:07Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:23Z (GMT). No. of bitstreams: 1 00384.pdf: 931217 bytes, checksum: 170cd2f3408ad5e430165e620436b412 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
40

Niveis do sup72Ge populados pelo decaimento beta sup(-) do sup72Ga

MEDEIROS, JOSE A.G. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:38:36Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:09Z (GMT). No. of bitstreams: 1 05834.pdf: 6637746 bytes, checksum: eac3b2442d4b06b5a8e3a4c9f46f1f9e (MD5) / Dissertacao (Mestrado) - IPEN / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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