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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.
111

Aplicação da espectroscopia de correlação angular perturbada na investigação de interações hiperfinas em compostos de háfnio, indio e cádmio com os ligantes Fsup(1-), OHsup(1-) e EDTA / Application of the perturbed angular correlation in the investigation of hyperfine interactions in compounds of hafnium, indium and cadmium with Fsup(1-), OHsup(1-) and EDTA ligands

AMARAL, ANTONIO A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:45Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:00Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
112

Estudo espectroscopico nuclear no Sn-117 pela tecnica da correlacao angular

BORGES, JOAO B. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:00Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:43Z (GMT). No. of bitstreams: 1 11261.pdf: 1447800 bytes, checksum: f0826edbe9dea480c0e4f236affa2502 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
113

Correlacoes angulares gama-gama no nucleo Rh-105

ESTEVES, VANICE A.P. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:30:15Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:28Z (GMT). No. of bitstreams: 1 00486.pdf: 1035700 bytes, checksum: 1673cd5fd2c3650224ca9a6df2b4fcdb (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
114

Availapp : Availapp och andra semesterplanerare

Försth, Sebastian January 2017 (has links)
The aim of this study has been to create and compare different holiday planners. The comparison takes place between availapp, Excel spreadsheets and absence. Availapp is a tailor-made vacation planning application for CGI Sundsvall / Härnösand that is fully scalable with mobile and desktops devices. The applikation automatically retrieves personal information from windowsAD at first login. The web application also takes into account social ethical aspects where we use encryption to ensure that information does not reach the wrong people. Also taking into account with PUL and GDPR for storing user information. Excel spreadsheets is CGI's current vacation planner consisting of an excel sheet with macron to ease the vacation planning. Absence is a commercial holiday planner aimed at companies to replace excel vacation planners. The comparison between availapp, excel spreadsheets and absence is evaluated according to a few key criteria, which is access, readability, navigation, functionality and startup of applications. The result is then compiled in a table to get an easy overview of the criteria for each application. After the compilation, it is found that availapp is the most suitable holiday planner according to the chosen criteria. / Målet med denna undersökning har varit att skapa och jämföra olika semesterplanerare. Jämförelsen sker mellan availapp, excelark och absence. Availapp är en skräddarsydd semesterplaneringsapplikation för CGI sundsvall/härnösand som är helt skalbar med mobil och skrivbord samt automatiskt hämtar personinformation från windowsAD vid första inloggning. Webbapplikationen tar även hänsyn till samhällsetiska aspekter där vi använder oss av kryptering för att säkerställa att information inte kommer till fel personer. Vi håller oss även till PUL och GDPR för lagring av användarinformation. Excelarket är CGI’s nuvarande semesterplanerare som består av ett excelark med macron för att underlätta semesterplaneringen. Absence är en kommersiell semesterplanerare som riktar sig till företag för att ersätta excel semesterplanerare. Jämförelsen mellan availapp, excelarket och absence utvärderas efter ett par nyckelkriterier vilket är åtkomst, läsbarhet, navigering, funktionalitet och uppstart av applikationerna. Resultatet är sedan sammanställt i en tabell för att få en lätt översikt över vilka kriterier varje applikation klara. Efter sammanställningen konstateras det att availapp är den mest lämpade semesterplaneraren efter dom valda kriterierna.
115

Calibration of the island effect: Experimental validation of closed-loop focal plane wavefront control on Subaru/SCExAO

N’Diaye, M., Martinache, F., Jovanovic, N., Lozi, J., Guyon, O., Norris, B., Ceau, A., Mary, D. 13 February 2018 (has links)
Context. Island effect (IE) aberrations are induced by differential pistons, tips, and tilts between neighboring pupil segments on ground-based telescopes, which severely limit the observations of circumstellar environments on the recently deployed exoplanet imagers (e.g., VLT/SPHERE, Gemini/GPI, Subaru/SCExAO) during the best observing conditions. Caused by air temperature gradients at the level of the telescope spiders, these aberrations were recently diagnosed with success on VLT/SPHERE, but so far no complete calibration has been performed to overcome this issue. Aims. We propose closed-loop focal plane wavefront control based on the asymmetric Fourier pupil wavefront sensor (APF-WFS) to calibrate these aberrations and improve the image quality of exoplanet high-contrast instruments in the presence of the IE. Methods. Assuming the archetypal four-quadrant aperture geometry in 8 m class telescopes, we describe these aberrations as a sum of the independent modes of piston, tip, and tilt that are distributed in each quadrant of the telescope pupil. We calibrate these modes with the APF-WFS before introducing our wavefront control for closed-loop operation. We perform numerical simulations and then experimental tests on a real system using Subaru/SCExAO to validate our control loop in the laboratory and on-sky. Results. Closed-loop operation with the APF-WFS enables the compensation for the IE in simulations and in the laboratory for the small aberration regime. Based on a calibration in the near infrared, we observe an improvement of the image quality in the visible range on the SCExAO/VAMPIRES module with a relative increase in the image Strehl ratio of 37%. Conclusions. Our first IE calibration paves the way for maximizing the science operations of the current exoplanet imagers. Such an approach and its results prove also very promising in light of the Extremely Large Telescopes (ELTs) and the presence of similar artifacts with their complex aperture geometry.
116

Determinação e análise da influência angular e eletrônica nas constantes de acoplamento nJCH em 2-X-4-t-butilcicloexanonas e 2-X-4-t-butilcicloexanóis (X=H, Me, F, Cl, Br) / Determination of NMR nJCH spin-spin coupling constants and analysis of their angular and electronic dependence in 2-X-4-t-butylcycloexanonas and 2-X-4-t-butylcycloexanols (X=H, Me, F, Cl, Br)

Favaro, Denize Cristina, 1987- 17 August 2018 (has links)
Orientador: Claudio Francisco Tormena / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-17T19:41:15Z (GMT). No. of bitstreams: 1 Favaro_DenizeCristina_M.pdf: 2968237 bytes, checksum: 07a91d8f375b71e3ddc4d4c9b7818162 (MD5) Previous issue date: 2011 / Resumo: A dissertação consiste de uma parte introdutória que versa sobre constantes de acoplamento JXH que seguem ou não uma relação de estrita dependência com o ângulo diedro, proposta por Karplus para JHH e por Aydin e Günther para JCH; apresentando como as interações hiperconjugativas afetam os valores das mesmas. Seguindo a estrutura da dissertação temos os resultados e discussão. Primeiro apresentamos a metodologia de HSQC-TOCSY-IPAP utilizada para determinação das constantes de acoplamento JCH. Posteriormente apresentamos uma racionalização para a diferença entre os acoplamentos JC2H6e para as cetonas cis/trans-2-X-4-t-butilcicloexanonas (X = H, Me, F, Cl e Br) e entre os alcoóis derivados. Mostramos, também, qual a influência do ângulo de ligação C2-C1-C6 na constante de acoplamento JC2H6e onde observamos que para a maioria dos compostos o valor de JC2H6e possui uma relação inversa com esse ângulo interno. Além disso, analisou-se o efeito das interações hiperconjugativas sC1-C6s*C2-Br, LP2(O)s*C1-C2 e LP3(X)s*C1-C2, onde as duas primeiras interações tornam mais efetiva a transmissão do acoplamento e a última retira densidade eletrônica do caminho a três ligações. Por fim, observamos a aplicabilidade das regras propostas por Marshall, Contreras e col. na racionalização da diferença dos valores de JC2H3a quando o heteroátomo ligado ao C2 se encontra na orientação axial ou equatorial / Abstract: It is presented an overview about heteronuclear coupling constants JXH and their strict dependence with the dihedral angle, as proposed by Karplus for JHH and by Aydin and Günther for JCH. It is also presented descriptions about the effects of hyperconjugative interactions on coupling constants and also on the HSQC-TOCSY-IPAP methodology for the measurements of long range heteronuclear coupling constants (JCH). The experimental values for JCH couplings obtained from HSQC-TOCSY-IPAP and rationalization of the difference between the JC2H6e for cis/trans-2-X-4-t-butylcyclohexanones and 2-X-4-t-butylcyclohexanols (X = H, Me, F, Cl and Br) based on the effects of bond angle C2-C1-C6 and hyperconjugative interactions involving the sC1-C6, LP2(O) and LP3(X) has been presented and discussed. The hyperconjugative interactions were studied with the Natural Bond Orbital (NBO) analyses. It was observed that interactions such as, sC1-C6s*C2-Br and LP2(O)s*C1-C2 increase the JC2H6e values and LP3(X)s*C1-C2 decreases this coupling constant values. Furthermore, we observed the applicability of the rules proposed by Marshall and Contreras in the rationalization of the difference between values of JC2H3a when heteroatom on carbon C2 is in the axial or equatorial orientation / Mestrado / Quimica Organica / Mestre em Química
117

Correlacao angular gama-gama para transicoes nos nucleos Br-81 e Br-83

MATHEUS, RENATO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:31:49Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:08Z (GMT). No. of bitstreams: 1 02290.pdf: 2034499 bytes, checksum: 345786d5696bbd6a7ec8457a8fa60c1d (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
118

Correlacoes angulares gama-gama no nucleo sup(84) Kr

JAHNEL, LUCIA C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:11Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:41Z (GMT). No. of bitstreams: 1 00973.pdf: 3680396 bytes, checksum: 62f3f85a25ae91726723f130884f9345 (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
119

Aplicação da espectroscopia de correlação angular perturbada na investigação de interações hiperfinas em compostos de háfnio, indio e cádmio com os ligantes Fsup(1-), OHsup(1-) e EDTA / Application of the perturbed angular correlation in the investigation of hyperfine interactions in compounds of hafnium, indium and cadmium with Fsup(1-), OHsup(1-) and EDTA ligands

AMARAL, ANTONIO A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:45Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:00Z (GMT). No. of bitstreams: 0 / O presente trabalho realiza a investigação dos parâmetros hiperfinos, incluindo a sua natureza dinâmica, em compostos ligantes em solução a temperatura ambiente (295 K) e resfriada (77K) através da espectroscopia de Correlação Angular γγ Perturbada (CAP). Para a realização das medidas experimentais, utilizou-se núcleos de prova radioativos de 111In111Cd, 181Hf181Ta e 111mCd111Cd, que decaem através de cascata gama. As amostras foram preparadas diluindo-se soluções com os núcleos radioativos em água, quando se investigou a interação do núcleo de prova com o ligante água; adicionando-se soluções com os núcleos radioativos em solução tampão, quando se investigou a interação do núcleo de prova com os íons ligantes provenientes do próprio tampão (CO32- e HCO31-) e com o OH1-; e adicionando-se soluções com os núcleos radioativos em soluções do ligante ácido etilenodiaminotetracético (EDTA), este em pH entre 4,0 e 5,0, (que corresponde ao pH da própria solução saturada do EDTA) e em solução tampão de pH entre 9 e 10. Assim foi possível investigar os efeitos gerados por cada um desses métodos de preparação de amostras nas medidas CAP. Finalmente foi feita uma análise comparativa para os vários métodos de inserção dos núcleos de prova na amostra, considerando-se aspectos químicos e nucleares. A inexistência de medidas para esse tipo de amostra, justifica a importância dos resultados obtidos. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
120

Estudo espectroscopico nuclear no Sn-117 pela tecnica da correlacao angular

BORGES, JOAO B. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:00Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:43Z (GMT). No. of bitstreams: 1 11261.pdf: 1447800 bytes, checksum: f0826edbe9dea480c0e4f236affa2502 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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