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Development and application of chemical probes for vibrational imaging by stimulated Raman scatteringHu, Fanghao January 2017 (has links)
During the last decade, Raman microscopy is experiencing rapid development and increasingly applied in biological and medical systems. Especially, stimulated Raman scattering (SRS) microscopy, which significantly improves the sensitivity of Raman scattering through stimulated emission, has allowed direct visualization of many species that are previously challenging with conventional fluorescence imaging. Compared to fluorescence, SRS imaging requires no label or small label on the target molecule, thus with minimal perturbation to the molecule of interest. Moreover, Raman scattering is free from complicated photophysical and photochemical processes such as photobleaching, and has intrinsically narrower linewidth than fluorescence emission. This allows multiplexed Raman imaging with minimal spectral crosstalk and excellent photo-stability.
To achieve the full potential of Raman microscopy, vibrational probes have been developed for Raman imaging. Multiple Raman probes with a few atoms in size are applied in Raman imaging with high sensitivity and specificity. An overview of both fluorescence and Raman microscopy and their imaging probes is given in Chapter 1 with a brief discussion on the SRS theory.
Built on the current progress of Raman microscopy and vibrational probes, I write on my research in the development of carbon-deuterium, alkyne and nitrile probes for visualizing choline metabolism (Chapter 2), glucose uptake activity (Chapter 3), complex brain metabolism (Chapter 4) and polymeric nanoparticles (Chapter 5) in live cells and tissues, as well as the development of polyyne-based vibrational probes for super-multiplexed imaging, barcoding and analysis (Chapter 6).
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O efeito raman ressonante e sua relação com transições eletrônicas em alguns complexos de metais de transição / The Raman resonance effect and its relation to electronic transitions in some complexes of transition metalsSantos, Paulo Sergio 30 June 1978 (has links)
O efeito Raman ressonante do complexo (NH4)4Mo2Cl8.NH4Cl.H2O, contendo o íon Mo2Cl84-, foi estudado tanto na temperatura ambiente como na de nitrogênio líquido. Com base nos resultados obtidos mostra-se que a explicação previamente oferecida por outros autores para o aparecimento de ressonância com excitação em 568,2 nm não é correta. É sugerida uma explicação diferente para este comportamento baseada nos espectros Raman e de absorção. A transferência de elétron fotoestimulada no íon complexo (NH3)5RuII-pz-CuII foi comprovada através do estudo do efeito Raman ressonante. Com base nos espectros Raman obtidos em condições de ressonância e também nas medidas de polarização, o estado eletrônico excitado envolvido foi caraterizado. Os perfis de excitação para v1 e 2vl do íon RuO42- em solução aquosa foram obtidos usando diversas radiações excitantes. Os perfis mostraram uma desintensificação das intensidades Raman pré-ressonantes na região da transição interna do íon. O efeito foi interpretado usando o tratamento proposto por Stein e col. para o efeito Raman anti-ressonante. / The Raman resonance effect of the complex (NH4)4Mo2Cl8.NH4Cl.H2O, containing the Mo2Cl84- ion, was investigated at both room and liquid nitrogen temperatures. On basis of the obtained results it is shown that the previous explanation given by others authors for the resonance observed with 568.2 nm excitation is not a correct one. A different explanation for this behaviour is suggested, based on the Raman and absorption spectra. The photostimulated electron transfer in the complex ion (NH3)5RuII-pz-CuII was confirmed trough the investigation of its Raman ressonance effect. The Raman ressonance spectra and the polarization measurements had enabled the characterization of the electronic excited state involved in the transition. The excitation profiles of v1 and 2v1 of the RuO42- ion in aqueous solution were obtained using several exciting radiations. The profiles present a de-enhancement of the pre-resonant Raman intensities in the region of the ion internal transition. This effect was interpreted using the treatment proposed by Stein et al. for the anti-resonance Raman effect.
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Pressure dependence of the luminescence and Raman modes in polyfluoreneMartin, Christopher M., January 2005 (has links)
Thesis (Ph.D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 28, 2007) Vita. Includes bibliographical references.
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Linear and nonlinear effects in Raman fiber amplifiers and lasersRavet, Gautier 11 June 2007 (has links)
RESUME
Parmi les divers processus permettant l'amplification optique indispensable aux systèmes de télécommunications par fibre, l'effet Raman, basé sur l'échange de puissance entre un signal et un laser de pompe de fréquence supérieure à travers un couplage avec les vibrations moléculaires de la silice, permet d'amplifier à n'importe quelle longueur d'onde avec une grande bande passante.
Un des inconvénients majeurs de cette technique est la forte puissance optique nécessaire à sa réalisation qui génère l'apparition de nombreux effets non linéaires potentiellement dommageables pour la bonne transmission du signal.
L'interaction des effets Kerr ou de la diffusion Brillouin avec les autres caractéristiques de la propagation dans les fibres peut entraîner une diminution des performances.
Dans la première partie de cette thèse, nous décrivons un nouveau processus d'élargissement spectral induit par l'effet Kerr dans les amplificateurs Raman fibrés.
Nous avons également mis à jour ce même processus dans les lasers Raman. L'application de ce phénomène à la suppression de la diffusion Brillouin est ensuite démontrée avec succès.
La deuxième partie de ce travail démontre comment tirer avantage des effets non linéaires afin de générer des impulsions optiques de haute puissance dans un laser Raman fibré.
Enfin, dans la troisième partie, nous proposons et démontrons l'application de deux nouvelles méthodes de caractérisation à la mesure de la distribution des effets Raman et Kerr le long des fibres optiques grâce à une technique de réflectométrie optique cohérente.
SUMMARY
Among the various processes that allow optical amplification that is required for fiber telecommunication systems, the Raman effect, based on the power exchange between a signal and a pump laser with higher frequency through a coupling with molecular vibrations of silica, enables to amplify at any wavelength with a large bandwidth.
One of the major drawbacks of this technique is the high power required to realize it, generating the appearance of numerous nonlinear effects, potentially harmful for the quality transmission.
The interplay between Kerr effects or Brillouin scattering and other propagation characteristics of optical fibers can lead to a decrease of the performances.
In the first part of this thesis we describe a new broadening mechanism induced by the Kerr effect in Raman fiber amplifiers. This effect was also discovered in Raman fiber lasers.
An application of this phenomenon as an efficient way to suppress Brillouin scattering is then successfully demonstrated.
The second part of this work demonstrated how to take advantage of optical nonlinearities to generate high peak power pulses with a Raman fiber laser.
Finally, in the third part, we propose and demonstrate the application of two new methods to measure the spatial distribution of Raman and Kerr effects along optical fibers thanks to a coherent optical reflectometry technique.
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The importance of the structure of alkali metal hydroxide solutions in decrystallizing cellulose IDimick, Bruce E. 01 January 1976 (has links)
No description available.
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Bazı amonyum türevi bileşiklerin kuramsal ve deneysel kırmızıaltı ve raman spektroskopileri ile incelenmesi /Gökce, Halil. Bahçeli, Semiha. January 2009 (has links) (PDF)
Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Fizik Anabilim Dalı, 2009. / Kaynakça var.
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Exciton spectroscopy using non-resonant x-ray Raman scattering /Feng, Yejun, January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 107-119).
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The development of Raman imaging microscopy to visualize drug actions in living cellsLing, Jian 28 August 2008 (has links)
Not available / text
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Vibrational reorganization energies of the LMCT transition of PdCI2(PPh3)2 and the MLCT transition of several Pt-acetylide complexesdetermined by resonance Raman intensity analysis蔡子良, Choi, Chi-leung, Dickson. January 1998 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
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MULTIPHOTON SPECTROSCOPY OF THIN FILMS AND SURFACES (NONLINEAR, WAVEGUIDES, INTERFACES)Van Wyck, Neal Edward January 1985 (has links)
No description available.
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