Darmstadt, Techn. Universiẗat, Diss., 1999. / Dateiformat: tar.gz, Dateien im PDF-Format.

Techn. Universiẗat, Diss., 1999--Darmstadt.

Duisburg, Essen, Univ., Diss., 2003. / Computerdatei im Fernzugriff.

Duisburg, Essen, Univ., Diss., 2003. / Computerdatei im Fernzugriff.

Duisburg, Essen, Universiẗat, Diss., 2003.

Ce travail de thèse porte sur la réalisation de deux instruments adaptés à l’étude de couches minces par spectrométrie Mössbauer du 57Fe par électrons de conversion (CEMS) et à leur utilisation pour la caractérisation de films épitaxiés de ferrite de bismuth BiFeO3 (BFO). Le premier dispositif est constitué d’un compteur proportionnel couplé à un module thermoélectrique. Il permet l’acquisition de manière simple et économique de spectres Mössbauer sur une gamme de température variant de 245 à 375K et sous une induction magnétique externe allant jusqu’à 1,4 T. Un second dispositif a été développé sur la base d’un channeltron™et d’un cryostat à circulation d’hélium pour des acquisitions allant jusqu’à 4 K. Les analyses CEMS ont été réalisées sur des couches minces de différentes épaisseurs de BFO (110) et (001) épitaxiées sur LaAlO3 et SrTiO3. Au-delà d’une épaisseur critique, les couches de BFO (110) présentent un mélange de phases magnétiques colinéaire et cycloïdale. La phase colinéaire présente un axe d’anisotropie suivant [001] dans le plan de la couche et lamodulation cycloïdale se propage dans un plan perpendiculaire à celui-ci. Des effets combinés de contraintes et dimensionnalité ont été avancés pour expliquer la déstabilisation de la cycloïde pour les couches les plus fines. Dans les couches minces de BFO (001) présentant une phase tétragonale de BFO, les mesures CEMS ont montré que la température de mise en ordre magnétique se rapproche de l’ambiante lorsque l’épaisseur des couches diminue. / This work is devoted to the development of two Mössbauer detectors dedicated to thin films studies by conversion electron Mössbauer spectrometry (CEMS), and to their use for the characterization of bismuth ferrite BiFeO3 (BFO) epitaxials thin films. The first designed instrument is composed of a proportional counter and a thermoelectric module. It allows CEMS acquisitions of Mössbauer spectra from 245 to 375K with an external magnetic field upto 1.4 T. The second device is based on a commercial channeltron™ and a continuous flow cryostat allowing measurements downto 4 K. The CEMS measurements have been performed on (110) and (001) oriented BFO layers with various thickness deposited on LaAlO3 et SrTiO3 substrates. Beyond a critical thickness, the (110) BFO exhibits a mixing of collinear and cycloidal magnetic phases. The collinear phase shows an anisotropy axis [001] direction which is located in the sample plane. The cycloid propagation plane have been found to be perpendicular to the sample plane. Both epitaxial strain and size effects have been proposed to explain the cycloid destabilization in the thinner films. In (001) BFO thin films, exhibiting a BFO tetragonal phase, the CEMS measurements have shown that the magnetic ordering temperature tends to decrease with the layer thickness.

The thesis aims at exploring what the role of career guidance services for CEMS students in their job search is, and at proposing a number of recommendations for further development of CEMS career services. First part of this thesis will provide us with a necessary theoretical background on career choice, career management and development, and career guidance. Then, CEMS and its current career services offer will be presented in brief. Finally, an analysis of a research that we have conducted within CEMS graduates community will enable us to formulate a number of recommendations for CEMS career services improvement.

Submitted by Henrique Alves Buriti (henrique.buriti@gmail.com) on 2015-01-09T10:43:10Z No. of bitstreams: 1 Henrique Buriti MPGI CEMS Thesis.pdf: 927867 bytes, checksum: f6c4884c00b16fe6e2841a4cd2aef012 (MD5) / Rejected by Luana Rodrigues (luana.rodrigues@fgv.br), reason: Bom dia Henrique, Por gentileza, faça as seguintes alterações na dissertação e poste novamente: 1 - O ano escrito ao final da capa e contracapa deve ser o ano de apresentação do trabalho (2014) e não de publicação. 2 - O texto da contracapa e da folha de apresentação deve ser em português, conforme exemplo enviado por e-mail. 3 - O abstract e o resumo devem ficar em páginas distintas. Qualquer dúvida, estou a disposição. Att, Luana de Assis Rodrigues Cursos de Pós-Graduação – Post Graduate Program (55 11) 3799-3492 SRA - Secretaria de Registros Acadêmicos on 2015-01-09T12:44:14Z (GMT) / Submitted by Henrique Alves Buriti (henrique.buriti@gmail.com) on 2015-01-09T14:34:08Z No. of bitstreams: 1 Henrique Buriti MPGI CEMS Thesis.pdf: 927867 bytes, checksum: f6c4884c00b16fe6e2841a4cd2aef012 (MD5) / Rejected by Luana Rodrigues (luana.rodrigues@fgv.br), reason: Olá Henrique, Por gentileza, antes de postar certifique-se de que as alterações solicitadas foram feitas e poste novamente: 1 - O ano escrito ao final da capa e contracapa deve ser o ano de apresentação do trabalho (2014) e não de publicação. 2 - O texto da contracapa e da folha de apresentação deve ser em português, conforme exemplo enviado por e-mail. 3 - O abstract e o resumo devem ficar em páginas distintas. Importante: o campo de conhecimento é a área do seu orientador, no caso é GESTÃO E COMPETITIVIDADE EM EMPRESAS GLOBAIS. Por favor, não se esqueça de alterar este item Qualquer dúvida, estou a disposição. Att, Luana de Assis Rodrigues Cursos de Pós-Graduação – Post Graduate Program (55 11) 3799-3492 SRA - Secretaria de Registros Acadêmicos on 2015-01-09T14:44:40Z (GMT) / Submitted by Henrique Alves Buriti (henrique.buriti@gmail.com) on 2015-01-09T14:57:51Z No. of bitstreams: 1 Henrique Buriti Thesis MPGI CEMS.pdf: 929802 bytes, checksum: 822846183f073d95729fb08c2dcbfd7a (MD5) / Approved for entry into archive by Luana Rodrigues (luana.rodrigues@fgv.br) on 2015-01-09T15:22:59Z (GMT) No. of bitstreams: 1 Henrique Buriti Thesis MPGI CEMS.pdf: 929802 bytes, checksum: 822846183f073d95729fb08c2dcbfd7a (MD5) / Made available in DSpace on 2015-01-09T16:59:50Z (GMT). No. of bitstreams: 1 Henrique Buriti Thesis MPGI CEMS.pdf: 929802 bytes, checksum: 822846183f073d95729fb08c2dcbfd7a (MD5) Previous issue date: 2014 / This thesis is mainly focused on the intrapreneurial level of CEMS students around the world. Organizations are seeking to hire people with an entrepreneurial personality. This means that companies are looking for someone with similar psychological traits as entrepreneurs who are capable of influence positively in firm’s innovation. Therefore, the research question is 'What is the CEMS intrapreneurial level?' The contribution of this thesis is to check whether CEMS students have high intrapreneurship level or not. In order to find out, the General measure Enterprising Tendency (GET) test was sent to these students. The main finding is that CEMS students have score which can located them in the Medium range, meaning they have an average level of intrapreneurship. Thus, it is possible to raise awareness on the intrapreneurial potential that they can achieve. Furthermore, this thesis hopes to grow a concern on this topic so that universities give more emphasis on it.

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