Thesis--Yale. / Includes bibliographical references.

Thesis--Yale. / Includes bibliographical references.

Orientador: Celio Pasquini / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-21T20:32:18Z (GMT). No. of bitstreams: 1 Ribeiro_LiviaPauliaDias_D.pdf: 4837120 bytes, checksum: 765fabab75a97dbaab34799ef8208379 (MD5) Previous issue date: 2012 / Resumo: Dois novos instrumentos analíticos, sem o uso de partes móveis, para obtenção de medidas polarimétricas nas regiões do visível (VIS) e infravermelho próximo (NIR) são descritos. Esses equipamentos consistem de um Polarímetro VIS/NIR com fonte de radiação tipo laser de diodo (532 nm, 650 nm e 1064 nm) e um Espectropolarímentro VIS dedicado à obtenção de curva de Dispersão Óptica Rotatória (ORD) e de espectro de absorção, simultaneamente. O método de determinação da rotação óptica empregado nos instrumentos utiliza a equação a = (45 - b)°, onde b é determinado pela função arco tangente da razão dos campos elétricos dos dois feixes produzidos pelo analisador, o qual é constituído por um cristal birrefringente. No desenvolvimento do polarímetro foram avaliados dois analisadores, Glan Laser e Cristal de Wollaston. O instrumento apresentou precisão de 0,003°, e o uso do Cristal de Wollaston permitiu torná-lo mais robusto e compacto, possibilitando que o equipamento possa, eventualmente, ser empregado em controle de qualidade de processos industriais. O espectropolarímetro utiliza um Filtro Óptico Acústico Sintonizável (AOTF), que opera na região do visível (450 nm a 800 nm), como monocromador e analisador simultaneamente, e com características inéditas para esse tipo de equipamento. A melhor precisão, de 0,009°, foi verificada para a media de 20 varreduras. Quando o instrumento é empregado para medida de rotação óptica na presença de uma espécie absorvente, a curva de ORD é imune a absorbância de até 0,3. Estes equipamentos contribuem para o avanço da área da polarimetria, uma vez que apresentam configurações inovadoras que as diferenciam dos equipamentos comercialmente disponíveis, pois nestes, os analisadores são girados mecanicamente para a determinação do ângulo de rotação do plano da radiação polarizada / Abstract: Two new analytical instruments, which preclude of any moving parts, are described to obtain polarimetric measurements in the visible (VIS) and near-infrared (NIR) spectral regions. These instruments consist of a VIS/NIR polarimeter with diode lasers as radiation source (532, 650 and 1064 nm) and a VIS spectropolarimeter aimed at simultaneously obtaining the optical rotatory dispersion (ORD) curve and absorption spectrum of samples. The method employed to determine the optical rotation in both instruments uses the equation a = (45 - b)°, where b given by arc tangent function ratio between the electrical fields of the beams produced by the polarization analyzer element, made of a birefringent crystal. The polarimeter design was evaluated using two analyzers, a Glan Laser and a Wollaston crystal. The instrument is capable of attaining a repeatability of 0.003°, and, when it uses a Wollaston crystal, to become an instrument more compact and robust, which could be used for in-line measurements of industrial processes. The spectropolarimeter employs an Acousto-Optical Tunable Filter (AOTF) operating as a wavelength selector in visible region (450-800 nm) and polarization analyzer element. This instrument is capable of generating absorption and optical rotation spectra of samples simultaneously, a new characteristic, considering this type of equipment. The repeatability of 0.009° was obtained for the average of 20 scans. When the optical rotation is measured in the presence of absorbent substance the ORD curve is immune to a maximum absorbance of 0.3. The instruments contribute to an important advance in polarimetry, as they show innovative designs, distinct from commercially available instruments, where the analyzers are rotated mechanically, aiming at the determination of the angle of the polarization plane / Doutorado / Quimica Analitica / Doutora em Ciências

This work presents the design, development, and testing of a field portable imaging spectropolarimeter that operates over the short-wavelength and middle-wavelength portion of the infrared spectrum. The sensor includes a pair of sapphire Wollaston prisms and several high order retarders to produce the first infrared implementation of an imaging Fourier transform spectropolarimeter, providing for the measurement of the complete spectropolarimetric datacube over the passband. The Wollaston prisms serve as a birefringent interferometer with reduced sensitivity to vibration when compared to an unequal path interferometer, such as a Michelson. Polarimetric data are acquired through the use of channeled spectropolarimetry to modulate the spectrum with the Stokes parameter information. The collected interferogram is Fourier filtered and reconstructed to recover the spatially and spectrally varying Stokes vector data across the image.The intent of this dissertation is to provide the reader with a detailed understanding of the steps involved in the development of this infrared hyperspectral imaging polarimeter (IHIP) instrument. First, Chapter 1 provides an overview of the fundamental concepts relevant to this research. These include imaging spectrometers, polarimeters, and spectropolarimeters. A detailed discussion of channeled spectropolarimetry, including a historical study of previous implementations, is also presented. Next a few of the design alternatives that are possible for this work are outlined and discussed in Chapter 2. The configuration that was selected for the IHIP is then presented in detail, including the optical layout, design, and operation. Chapter 3 then presents an artifact reduction technique (ART) that was developed to improve the IHIP's spectropolarimetric reconstructions by reducing errors associated with non-band-limited spectral features. ART is experimentally verified in the infrared using a commercial Fourier transform spectrometer in combination with Yttrium Vanadate as well as Cadmium Sulfide retarders.The remainder of this dissertation then details the testing and analysis of the IHIP instrument. Implementation of ART with the IHIP as well as the employed calibration techniques are described in Chapter 4. Complete calibration of the IHIP includes three distinct processes to provide radiometric, spectral, and polarimetric calibration. With the instrument assembled and calibrated, results and error analyses are presented in Chapter 5. Spectropolarimetric results are obtained in the laboratory as well as outdoors to test the IHIP's real world functionality. The performance of the instrument is also assessed, including experimental measurement of signal-to-noise ratio (SNR), and an analysis of the potential sources of systematic error (such as retarder misalignment and finite polarizer extinction ratio). Chapter 6 presents the design and experimental results for a variable Wollaston prism that can be added to the IHIP to vary the fringe contrast across the field of view. Finally, Chapter 7 includes brief closing remarks summarizing this work and a few observations which may be useful for future infrared imaging Fourier transform channeled spectropolarimeter instruments.

No description available.

Cette thèse aborde la problématique des transferts de chaleur dans les micro et nanoystèmes. La première partie concerne la conduction thermique dans l'air. La microscopie à force atomique thermique dite SThM est présentée, et la sonde résistive Wollaston est analysée afin de pouvoir être utilisée à haute température. Les pertes thermiques de la sonde dans l'air environnant sont mesurées en fonction de la pression. L'échange thermique entre la sonde chaude et un échantillon froid est déterminé en fonction de la distance pointe-échantillon. Une modélisation simple de l'expérience, avec des lignes de flux parallèles, tend à démontrer un comportement qui dévie de la diffusion thermique de Fourier. Une étude numérique mettant en jeu une pointe pyramidale nanométrique est ensuite effectuée à l'aide d'une méthode de Monte-Carlo dans le but d'analyser le transport thermique balistique.<br />La seconde partie aborde le rayonnement thermique de champ proche entre les corps métalliques. Il apparaît que le transfert radiatif est différent de celui des matériaux polaires lorsque les distances entre deux corps sont nanométriques. Ceci n'est pas dû à un phénomène modélisable avec l'optique non-locale. Le flux est en fait essentiellement d'origine magnétique et met en jeu des courants de Foucault stochastiques, pris en compte par la contribution dipolaire magnétique dans le cas d'une nanoparticule. Une longueur caractéristique du transfert est l'épaisseur de peau. Elle permet notamment d'expliquer une expérience récente.<br />La possibilité de mesurer le rayonnement de champ proche avec le microscope SThM est également évaluée.

Doctor of Philosophy / This thesis examines the transmission of Protestantism to Australia by the early British colonists and its consequences for their engagement with the land between 1788 and 1850. It explores the ways in which colonists gave religious meaning to their surrounds, particularly their use of exile and exodus narratives to describe journeying to the colony and their sense of their destination as a site of banishment, a wilderness or a Promised Land. The potency of these scriptural images for colonising Europeans has been recognised in North America and elsewhere: this study establishes and details their significance in early colonial Australia. This thesis also considers the ways in which colonists’ Protestant values mediated their engagement with their surrounds and informed their behaviour towards the land and its indigenous inhabitants. It demonstrates that leading Protestants asserted and acted upon their particular values for industry, order, mission and biblicism in ways that contributed to the transformation of Aboriginal land. From the physical changes wrought by industrious agricultural labour through to the spiritual transformations achieved by rites of consecration, their specifically Protestant values enabled Britons to inhabit the land on familiar material and cultural terms. The structural basis for this study is provided by thematic biographies of five prominent colonial Protestants: Richard Johnson, Samuel Marsden, William Grant Broughton, John Wollaston and John Dunmore Lang. The private and public writings of these men are examined in light of the wider literature on religion and colonialism and environmental history. By delineating the significance of Protestantism to individual colonists’ responses to the land, this thesis confirms the trend of much recent British and Australian historiography towards a more religious understanding of the eighteenth and early nineteenth centuries. Its overarching argument is that Protestantism helped lay the foundation for colonial society by encouraging the transformation of the environment according to the colonists’ values and needs, and by providing ideological support for the British use and occupation of the territory. Prominent Protestants applied their religious ideas to Australia in ways that tended to assist, legitimate or even necessitate the colonisation of the land.

Doctor of Philosophy / This thesis examines the transmission of Protestantism to Australia by the early British colonists and its consequences for their engagement with the land between 1788 and 1850. It explores the ways in which colonists gave religious meaning to their surrounds, particularly their use of exile and exodus narratives to describe journeying to the colony and their sense of their destination as a site of banishment, a wilderness or a Promised Land. The potency of these scriptural images for colonising Europeans has been recognised in North America and elsewhere: this study establishes and details their significance in early colonial Australia. This thesis also considers the ways in which colonists’ Protestant values mediated their engagement with their surrounds and informed their behaviour towards the land and its indigenous inhabitants. It demonstrates that leading Protestants asserted and acted upon their particular values for industry, order, mission and biblicism in ways that contributed to the transformation of Aboriginal land. From the physical changes wrought by industrious agricultural labour through to the spiritual transformations achieved by rites of consecration, their specifically Protestant values enabled Britons to inhabit the land on familiar material and cultural terms. The structural basis for this study is provided by thematic biographies of five prominent colonial Protestants: Richard Johnson, Samuel Marsden, William Grant Broughton, John Wollaston and John Dunmore Lang. The private and public writings of these men are examined in light of the wider literature on religion and colonialism and environmental history. By delineating the significance of Protestantism to individual colonists’ responses to the land, this thesis confirms the trend of much recent British and Australian historiography towards a more religious understanding of the eighteenth and early nineteenth centuries. Its overarching argument is that Protestantism helped lay the foundation for colonial society by encouraging the transformation of the environment according to the colonists’ values and needs, and by providing ideological support for the British use and occupation of the territory. Prominent Protestants applied their religious ideas to Australia in ways that tended to assist, legitimate or even necessitate the colonisation of the land.