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Patil, Raj. "Deep UV Raman Spectroscopy." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/613378.
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This thesis examines the performance of a custom built deep UV laser (257.5nm) for Raman spectroscopy and the advantages of Raman spectroscopy with a laser in the deep UV over a laser in the visible range (532 nm). It describes the theory of resonance Raman scattering, the experimental setup for Raman spectroscopy and a few Raman spectroscopy measurements. The measurements were performed on biological samples oak tree leaf and lactobacillus acidophilus and bifidobacteria from probotioc medicinal capsules. Fluorescence free Raman spectra were acquired for the two samples with 257.5 nm laser. The Raman spectra for the two samples with a 532nm laser was masked with fluorescence. Raman measurements for an inorganic salt sodium nitrate showed a resonance Raman effect with 257.5 nm laser which led to enhancement in the Raman intensity as compared to that with 532 nm laser. Therefore we were able to demonstrate two advantages of deep UV Raman spectroscopy. First one is the possibility of acquiring fluorescence free spectra for biological samples. Second is the possibility of gaining enhancement in Raman intensity due to resonance Raman effect. It was observed that 257.5 nm laser requires optimization to reduce the bandwidth of the laser to get better resolution. The 257.5 nm laser also needs to be optimized to obtain higher power to get better signal to noise ratio. The experimental setup can also be further improved to obtain better resolution. If the improvements required in the setup are implemented, the deep UV Raman setup will become an important tool for spectroscopy.
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Waldron, Daniel E. "Instrument design in UV polarised spectroscopy." Thesis, University of Warwick, 2011. http://wrap.warwick.ac.uk/51549/.
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Biological macromolecules are becoming increasingly important as a target for pharmaceutical research. Structural examination of this class of compounds is vital, both in terms of understanding the three-dimensional structures these molecules form as well as for quality control of bio-pharmaceutical products. UV polarised spectroscopy, such as circular dichroism (CD) is a powerful tool for this form of analysis, rapidly providing the user with structural information on the sample. The ease of data analysis combined with its non-destructive nature make UV polarised spectroscopy an ideal tool for this purpose. However, limitations in the current instrumentation, especially in terms of sample handling have placed significant barriers in the way of fully realising the potential of these techniques. To address the weaknesses of the currently available UV polarised spectroscopy accessories, new devices have been designed and tested to increase the utility of such techniques. A low volume capillary sample holder has been developed which significantly reduces the sample requirements for circular dichroism without loss of signal quality. This advance has been coupled with an HPLC auto-sampler to create a device that can process 96-well and in some cases 384- well plates. This device opens up a host of new applications for polarised UV spectroscopy, including refolding screening as well as freeing up user time. Additionally, a high precision demountable micro scale cuvette has been developed that reproducibly assembles to the same path length every time. The percentage error of path-length for this new cuvette is of the same order as currently commercially available 1 mm cuvettes. This new accessory should prove highly advantageous for the bio-pharmaceutical industry, as it allows accurate path-length CD analysis for high concentration samples. Additionally, the first confirmed linear dichroism (LD) spectrum of a bacterium and flagella are reported, opening up the potential for real time UV spectroscopic analysis of living bacteria. By using the work contained within this thesis, it should be possible to construct a new form of high path-length accuracy, low volume, multiple-sample UV polarised spectroscopy accessory that could be used for both CD and LD analysis.
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McCarthy, Richard Ivor. "GUSTO : a differential UV absorption spectroscopy instrument." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430743.
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O'Keeffe, Patrick. "Photodissociation dynamics and UV spectroscopy of ozone." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/12716.
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The UV adsorption and photodissociation dynamics have been extensively studied by spectroscopic analysis of both the atomic and diatomic photofragments. Central to the study is the UV absorption which consists of the extremely intense Hartley band (200 - 310nm) and the less intense structured tail to lower energy called the Huggins bands (310 - 360 nm). The dissociation channels along with their thermodynamic thresholds for the dissociation of vibrationally relaxed ground state ozone are as follows: (A) O3 + hn (r) O(3PJ) + O2 (X 3 S-g) (1178 nm) (B) (r) O(3PJ) + O2 (a 1 Dg) (612 nm) (C) (r) O(3PJ) + O2 (b 1 S+g) (463 nm) (D) (r) O(1D) + O2 (X 3 S-g) (411 nm) (E) (r) O(1D) + O2 (a 1 Dg) (310 nm) The contribution of the spin-forbidden channels to Huggins band photodissociation was quantified using Resonance Enhanced Multiphoton Ionisation (REMPI) detection of the O (3P0) fragments combined with a delayed pulsed field extraction technique. The translational angular properties of the photofragments were measured as part of this technique. The observed trimodal velocity distribution of the O (3 P0) fragments was suggested to be a result of the different amounts of internal energy taken from the dissociation event by the diatomic co-fragments of channels (A), (B) and (C). However, a bimodal vibrational distribution of one of the channels could not be excluded at this stage as the slowest velocity peak of the O (3P0) fragments may be due to formation of high vibrational levels of the diatomic fragments of channels (A) or (B). REMPI spectroscopy was used to detect the diatomic photofragments in a rotationally and vibrationally selective manner. In these experiments ozone was photolysed with tunable UV radiation and the fragments were state selectivity ionised using (2 + 1) REMPI via the O2 (d 3ssg 1IIg) state using a second probe laser. This Rydberg state was found to be heavily perturbed by nearby valence state, yet it was possible to identify O2 (b 1 S+g, v = 0) fragments produced via spin-forbidden dissociation from a singlet state of ozone excited by absorption in the Huggins band region.
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Vuong, Phuong. "Optical spectroscopy of boron nitride heterostructures." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS075/document.
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Le nitrure de bore hexagonal (h-BN) est un semi-conducteur à large bande interdite (~ 6 eV) avec une stabilité thermique et chimique très élevées lui offrant la possibilité d'être utilisé dans des dispositifs fonctionnant dans des conditions de fonctionnements extrêmes. La nature indirecte de la bande interdite dans h-BN a été étudiée à la fois par des calculs théoriques et par des expériences. Un exciton indirect et des recombinaisons assistées par phonons dans h-BN ont été observées par photoluminescence.Durant cette thèse, nous avons étudié les propriétés optiques de cristaux massifs et de couches hétéro-épitaxiales de nitrure de bore hexagonal. Nous avons étudié des échantillons provenant de différentes sources et des cristaux qui ont été fabriqués en utilisant différentes méthodes de croissance pour nous permettre de mesurer les propriétés optiques intrinsèques de h-BN. Nous rapportons l'impact des symétries des phonons sur la réponse optique du h-BN en effectuant des mesures photoluminescence résolues par polarisation. L’analyse des données en polarisation, nous permet de mesurer la contribution du phonon manquant, celui qui n'a pas été détectée avant cette thèse. En suite, nous démontrons que l'origine de la structure fine du spectre de PL provient pour chaque réplique phonon d’une diffusion complémentaire de type Raman faisant intervenir le mode de phonon E2g à basse énergie (mode de cisaillement inter-feuillets). Les spectroscopies de photoluminescence et de diffusion inélastique Raman ont été combinées pour quantifier l'influence des effets isotopiques sur les propriétés optiques de h-BN ainsi pour révéler que les modifications des interactions de van de Waals liées à l'utilisation de 10B et 11B ou du bore naturel pour la croissance de cristaux h-BN massifs.Enfin, nous étudions des epitaxis de h-BN crues par Épitaxie sous Jets Moléculaires. L'utilisation conjointe de l’imagerie par microscopie à force atomique (AFM) et de la spectroscopie de photoluminescence permet de comprendre la première observation de recombinaison assistée par phonons dans des épitaxies de h-BN sur le saphir et le graphite. Ce résultat indique que la croissance de h-BN à large échelle par méthode épitaxiales est en voie d'acquérir la maturité nécessaire au développement technologique de h-BNHexagonal boron nitride (h-BN) is a wide bandgap (~ 6 eV) semiconductor with a very high thermal and chemical stability often used in devices operating under extreme conditions. The indirect nature of the bandgap in h-BN is investigated by both theoretical calculations and experiments. An indirect excion and phonon-assisted reombinations in h-BN are observed in photoluminescene spectroscopy.This thesis focus on the optical properties of bulk and epilayers of h-BN. We investigated samples from different sources grown different methods in order to confirm the intrinsic optical properties of h-BN. We report the impact of the phonon symmetry on the optical response of h-BN by performing polarization-resolved PL measurements. From them, we will measure the contribution of all the phonon-assisted recombination which was not detected before this thesis. We follow by addressing the origin of the fine structure of the phonon-assisted recombinations in h-BN. It arises from overtones involving up to six low-energy interlayer shear phonon modes, with a characteristic energy of about 6.8 meV.Raman and photoluminescence measurements are recorded to quantify the influence of isotope effects on optical properties of h-BN as well as the modifications of van de Waals interactions linked to utilization of 10B and 11B or natural Boron for the growth of bulk h-BN crystals.Finally, we study h-BN thin epilayers grown by Molecular Beam Epitaxy at Nottingham University, atomic force microscopy (AFM) images and photoluminescence features are combined to confirm the first observation of phonon-assisted recombination in high quality thin h-BN epilayers grown on c-plane sapphire and Highly Ordered Pyrolitic Graphite. This demontrates that large scale growth of h-BN by epitaxy is getting a technologically required maturity
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Pertenais, Martin. "Spectropolarimétrie stellaire UV et visible depuis l'espace." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30252/document.
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Ces dernières décennies, des champs magnétiques ont été détectés dans quasiment tous les types d'étoiles. Ces découvertes ont donné lieu à des études innovantes sur la cartographie des champs magnétiques et leur impact sur l'environnement stellaire. Pour aller encore plus loin il est nécessaire d'allier la spectroscopie à la polarimétrie, dans l'UV et le visible. L'UV permet d'étudier les vents stellaires et l'environnement circumstellaire, tandis que le visible permet d'étudier la surface de l'étoile. La spectropolarimétrie UV+visible permet ainsi d'étudier les magnétosphères dans leur globalité. Ceci doit être fait sur au moins une période complète de rotation de l'étoile. Pour cela, il faut aller dans l'espace, à la fois pour atteindre le domaine UV et pour obtenir des observations ininterrompues sur une période de rotation stellaire complète. Le consortium international UVMag a été créé en 2010 pour discuter, étudier et promouvoir une mission spatiale pour l'étude des magnétosphères stellaires via de la spectropolarimétrie spatiale dans les domaines UV et visible simultanés. D'un point de vue technique, la spectroscopie spatiale pure, y compris dans l'UV, a déjà été utilisée avec succès, par exemple sur IUE, et serait très performante avec les détecteurs et les technologies disponibles aujourd'hui. Par contre, le spectropolarimètre UV+visible est la partie instrumentale la plus ambitieuse pour une future mission spatiale. En effet, alors que les français (en particulier le LESIA et l'IRAP) sont les spécialistes de ce type de spectropolarimètres dans le visible pour des télescopes au sol (comme ESPaDOnS au CFHT ou Narval au TBL), aucun instrument de ce type n'a encore été embarqué sur une mission spatiale, encore moins en UV. La première partie de ma thèse consistait à concevoir le design optique du module polarimétrique pour le spectropolarimètre de la mission Arago, dans le cadre du consortium UVMag. J'ai donc étudié et recherché différents concepts innovants qui pourraient s'adapter aux contraintes très particulières de cet instrument. En effet, les spécifications imposent l'utilisation d'un unique polarimètre pour tout le domaine spectral [119-888] nm. Les contraintes du spatial s'ajoutent à cela avec un besoin de compacité, légèreté et robustesse. Je me suis concentré sur 2 concepts de polarimètre différents, un premier basé sur le module de polarisation de l'instrument X-Shooter avec une modulation temporelle de la polarisation et une achromatisation des efficacités d'extraction des paramètres de Stokes et un second basé sur une modulation spatiale de la polarisation, permettant d'obtenir un polarimètre statique. J'ai adapté ces 2 concepts aux spécificités d'Arago et intégré ces 2 systèmes au design optique global de l'instrument. Le premier concept de modulation temporelle a été choisi pour l'instrument d'Arago qui a été soumis à l'ESA dans le cadre des appels Cosmic Vision M4 et M5. Dans un deuxième temps, l'objectif de ma thèse était de prouver la faisabilité des concepts évoqués plus hautOver the last few decades, magnetic fields have been detected in almost all kinds of stars. This led to innovative studies on the mapping of magnetic fields and their impact on the circumstellar environment. To go further, we need to use spectroscopy and polarimetry together, in the UV and visible range. The UV domain is used to study the stellar wind and stellar environment, whereas the visible range allows to study the surface of the star. UV+visible spectropolarimetry enables the global study of magnetospheres. This has to be done over at least one rotation period of the star. Therefore, we need to go to space in order to see the UV range and to obtain uninterrupted observations on a complete stellar rotation period. The international consortium UVMag has been created in 2010 to discuss, study and promote a space mission for the study of stellar magnetospheres using simultaneous UV and visible space spectropolarimetry. From the technical point of view, pure spectroscopy in space, both in the UV and visible ranges, has already been successfully used, for example on IUE, and would be very efficient with current detectors and technologies. On the other hand, the UV+visible spectropolarimeter is the most ambitious instrumental challenge for a future space mission. Indeed, until now, no such optical spectropolarimeter has flown on a space mission, despite the fact that the French (particularly the LESIA and IRAP laboratories) are the specialists for such instruments (such as ESPaDOnS at CFHT or Narval at TBL). The first part of my thesis consisted in elaborating the optical design of the polarimetric module for the spectropolarimeter of the space mission Arago, in the framework of the UVMag consortium. I studied various innovative concepts that could be adapted to the specific constraints of this instrument. The specifications indeed show the need for a unique polarimeter covering the complete spectral range [119-888] nm. Moreover, the usual compacity, lightness and robustness constraints of a space instrument are added to these specifications. I focused my work on 2 different polarimeter concepts, a first one based on the polarimetric module of the X-shooter instrument using a temporal modulation and an achromatization of the extraction efficiencies of the Stokes parameters, and a second one based on spatial modulation of the polarization, offering a static polarimeter. I adapted these 2 concepts to the specific constraints of Arago and integrated them to the complete optical design of the instrument. The first concept, using temporal modulation, has been chosen as the baseline for the instrument proposed to ESA for the Cosmic Vision calls M4 and M5. The goal was then to demonstrate the feasibility of the two concepts
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Beeching, Levi James. "Photoelectron spectroscopy of some atmospherically important species and heavy metal compounds." Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250077.
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Li, Jianping. "High-resolution UV-Vis-NIR fourier transform imaging spectroscopy and its applications in biology and chemistry." HKBU Institutional Repository, 2010. http://repository.hkbu.edu.hk/etd_ra/1151.
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Coleman, Martin. "Analysis of fluvial dissolved organic carbon using high resolution UV-visible spectroscopy and Raman spectroscopy." Thesis, University of Glasgow, 2017. http://theses.gla.ac.uk/8539/.
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This dissertation focusses on some advancements in methodology for measuring and analysing dissolved organic carbon (DOC): analysing data from a high resolution sensor generating DOC concentrations, [DOC] and secondly the use of Raman spectroscopy to analyse the composition of DOC. Recent advances in sensor technology have enabled the collection of DOC data with greater frequency over extended time periods than was previously possible through manually collecting water samples. In this research a time series of 30 minute [DOC] data for 2.5 years from Drumtee water, a peaty catchment in Scotland, was generated and analysed using a Spectro::lyserTM from S::CanTM, with a customised algorithm for calculating [DOC]. The time series revealed details of events and strong seasonal variation in the [DOC], with a range of 8.0 mg/l to 55.7 mg/l. During the same time period measurements made using manual sampling of river water were very similar, ranging from 10.2 mg/l to 81.1 mg/l (with the second largest value at 64.1 mg/l). Similar DOC export budgets were calculated from Spectro::lyserTM measurements and from the laboratory-analysed samples for both the hydrological year 2012/13 (HY 2012/13) and hydrological year 2013/14 (HY 2013/14). For the HY 2012/13 year the DOC budgets using the field collected data and the laboratory collected data were 16.6 gCm2.yr-1 and 19.8 gCm2.yr-1 respectively. For the HY 2013/14 year the DOC budgets using the field collected data and the laboratory collected data were 18.1 gCm2.yr-1 and 19.5 gCm2.yr-1 respectively. The similarity between the budgets calculated using the high-resolution [DOC] sensor and the budget calculated using laboratory measured [DOC] samples indicated that seasonal variation had a greater influence on export budgets than short term events had. GAMs were used to model the high resolution [DOC] data, and the model generated an R2 value of 0.75 and a p-value of < 2.2 x 10-16. It was also identified statistically that there were regular [DOC] dilutions during events and that these dilutions tended to coincide with the time period when discharge was increasing most rapidly. To identify relationships and periodicities in the high resolution [DOC] time series that would otherwise be challenging to identify three forms of wavelet analysis were used. These were continuous wavelet transforms (CWTs), maximal overlap discrete wavelet transforms (MODWTs) and wavelet coherence transforms (WTCs). Using the WTCs, it was determined that there were short term correlations between the [DOC] and pH between 25 June 2013 and 17 July 2013, between [DOC] and SC during 7 August 2013 and 7 October 2013 and between [DOC] and water temperature during 19 June 2013 and 30 June 2013. Although the although the relationship between [DOC] and temperature is strong over a full year it was over these shorter time periods the weakest of the three relationships established. Identifying this coherence was not possible using bivariate analysis and the long periods of no coherence obscured these responses when analysing the data on scatter plots. Although wavelet analysis has been used in other applications this is one of the first instances in which this technique has been applied to [DOC] time series. Raman spectroscopy, conducted using a 785 nm laser, was explored as an analytical tool that could enable a better understanding of DOC composition, as an alternative to the use of fluorescence spectroscopy. Tests were conducted using both Stokes and anti-Stokes Raman spectroscopy measurements with the best results obtained using anti-Stokes Raman spectroscopy. Solid phase measurements were made of glucose, fructose, sucrose, glycine, tyrosine, tryptophan and phenylalanine, but only the glucose produced a measurable spectrum of these substances. Measurements (powders and solutions) were made of humic and fulvic acids and these produced spectra that were measurably different from the background signals. The limit of detection was measured to be approximately 500 mg/l for both the humic acid and fulvic acid. It was identified that comparing the sections of the measured spectra between wavenumbers -1100 cm-1 to -1400 cm-1 to -1800 cm-1 to -2000 cm-1 could be used to differentiate between humic and fulvic acids. In summary, this research has focussed on the use of use high resolution sensor technology to generate and then analyse a long time series in a fluvial system with a particularly high [DOC], and made advances in being able to model the [DOC] using a GAM model, despite the complex relationship measured between discharge and [DOC]. Additionally, wavelet analysis has been applied to a [DOC] data set to identify trends in the [DOC] time series that would otherwise be hard to identify. Wavelet analysis has been applied to other geophysical time series such as those found in atmospheric research, but this appears to be the first time it has been applied to [DOC]. Additionally, the use of the anti-Stokes region of the Raman spectra has allowed identification of humic and fulvic acids, and established a limit of detection. Furthermore, an absorbance ratio was identified that can be used to determine whether a solution of humic substances is dominated primarily by humic acid or fulvic acid. This research appears to be the first study to explore this.
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Kabagambe, Benjamin. "Spectroscopic investigation of proteins : UV resonance Raman studies of apomyoglobin /." Saarbrücken, Germany : VDM Verlag Dr. Müller, 2008. http://etd.library.pitt.edu/ETD/available/etd-10232007-094038.
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Thesis (M.S.)--University of Pittsburgh, Department of Chemistry, 2007.Thesis advisor: Sanford A. Asher. Also available as an electronic book in PDF on the University of Pittsburgh Library Web site. Bibliography: p. 37-41.
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Addison, Christopher James. "Investigating biomolecular structure using fiber-optic UV resonance Raman spectroscopy." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37016.
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The observation of biomolecular structure is critical for the fundamental understanding of biological function. In this work, Fiber-optic UV Resonance Raman Spectroscopy (FO-UVRRS) was employed to study a number of structure-function relationships.
A suite of metal-containing dioxygenase enzymes were studied in order to determine the substrate protonation state in the enzyme-substrate complex. Two enzymes with a high degree of sequence identity were studied, where one naturally incorporates a Fe²⁺ metal and the other uses Mn²⁺. Both enzymes react with the same substrate to form an equivalent muconic semialdehyde product. The enzymes are capable of incorporating the non-native metal into the enzymes with no effect on the kinetic properties. The Raman results show that the nature of the metal has no effect on the substrate protonation state.
The degradation of 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA) by BphD in the biphenyl catabolic pathway was studied using FO-UVRRS. Previous reports suggest that enol-keto tautomerization was a critical step in the mechanism of the carbon-carbon bond hydrolase. Hydrolytically impaired variants of BphD were used to study the binding mode of HOPDA. The results show that HOPDA binds to these variants in a strained-enolate geometry and does not undergo an enol-keto tautomerization upon enzyme binding.
A fundamental FO-UVRRS study of locked nucleic acid (LNA) olgiomers was performed. LNA bases contain a C4’ to O2’ methylene bridge within the furanose ring of the nucleotide. The research results show that incorporation of a LNA induces a conformational change in the glycosyl bond between the backbone and the base. The results also show that incorporation of an LNA base induces changes in the secondary structure of the nucleic acid.
In another study, chemical contamination of synthetic DNA oligomers was observed using FO-UVRRS. The data showed that commercially-available oligomers purified using standard desalting conditions are contaminated with residual benzamide. The results show that a previously assigned –NH₂ scissors vibration in the Raman study of oligomers overlaps with a prominent benzamide vibrational band, calling into question these previous assignments. The results also demonstrate that the extent of benzamide contamination varies from sample-to-sample and between different commercial sources.
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Dogra, Jody A. Busch Kenneth W. Busch Marianna A. "Multivariate analyses of near-infrared and UV spectral data." Waco, Tex. : Baylor University, 2009. http://hdl.handle.net/2104/5347.
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Anisur, Rahman. "PREDICTION OF FISH FRESHNESS USING UV-VISIBLE SPECTROSCOPY OF EYE FLUID." Kyoto University, 2015. http://hdl.handle.net/2433/202812.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第19378号
農博第2148号
新制||農||1037(附属図書館)
学位論文||H28||N4958(農学部図書室)
32392
新制||農||1037
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 近藤 直, 教授 飯田 訓久, 准教授 小川 雄一
学位規則第4条第1項該当
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Qin, Wenhua. "Application of a CuBr laser to the UV spectroscopy of NaI /." Title page, contents and summary only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phq113.pdf.
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Mier, Lynetta M. "Monitoring Electron Transfer Reactions using Ultrafast UV-Visible and Infrared Spectroscopy." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1339440446.
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Moreno, Ivan Daniel. "Towards the Investigation of Ultrafast Directed Excite-State Isomerization in BBR3 and PBR3 with sub-50 fs Deep-UV/UV laser pulses." Bowling Green State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1404740168.
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Quiret, Samuel. "Circum galactic medium emission : from modeling to detection by a dedicated UV space mission." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4735/document.
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L’évolution des galaxies est un sujet relativement débattu en astronomie extra-galactique, étant donné que la plupart des mécanismes responsables des propriétés observées dans les galaxies (masse, taux de formation d’étoiles, contenu en métaux, moment angulaire) sont encore peu contraints et certains ne sont probablement même pas encore observés. Ma thèse porte sur une analyse de la région entourant les galaxies, connue sous le nom de Milieu Circum Galactique (MCG). Le MCG est à l’interface entreles galaxies et le Milieu Inter Galactique (MIG) et est considéré comme le lieu de prédilection pour les échanges gazeux et énergétiques entre les galaxies et le MIG, ce qui en fait la clé pour une meilleure compréhension de l’évolution des galaxies et du destin des baryons. Je présenterai dans un premier temps l’analyse d’un échantillon de systèmes à forte absorption issuent de la spectroscopie de quasars en absorption qui tracent les régions denses en hydrogène généralement associées au MCG des galaxies.Dans un deuxième temps, je présenterai ma contribution au développement d’une mission ballon embarquant un spectrographe UV, FIREBall-2, spécialement conçu pour observer l’émission faible et diffuse du MCG des galaxies à décalage vers le rouge inférieur à 1. D’un point de vue technique, je présenterai l’étude du composant optique clé de l’instrument: le réseau. D’un point de vue modélisation, je décrirai une simulation complète des observations, qui servira à la préparation du vol prévu pour l’Automne 2017notamment en ce qui concerne la sélection des cibles, la stratégie observationelle et le traitement des donnéesThe evolution of galaxies is a rather hot topic in extra galactic astronomy, as many of the main mechanisms underlying the observed properties of galaxies (mass, star formation rate, metal content, angular momentum) are still poorly constraints and many of them are probably undiscovered yet. My thesis focuses on an analysis of the region surrounding galaxies, known as the Circum Galactic Medium (CGM). The CGMinterfaces the galaxy with the Inter Galactic Medium (IGM) and is thought to be the most active location for gas and energy exchanges (in and out), which makes it a key ingredient towards a better understanding of galaxy evolution and the fate of all baryons. I will present in a first part, the analysis of a sample of strong absorption features based on quasar absorption spectroscopy, that probe the dense neutral hydrogen usually associated with galaxies’ CGM. In a second part, I will present my contribution to the development of a balloon-borne UV spectrograph, FIREBall-2, specifically designed to observe the faint and diffuse emissions from the CGM of galaxies at redshifts below 1. On the technical side, I will present the characterization of the key optical component ofthe instrument: the grating. On the modeling side, I will focus on an end-to-end pixel simulation of the observations to prepare for the upcoming flight, planned for Autumn 2017, in terms of target selection, observational strategy and data analysis
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Howie, Wendy Helen. "Molecular structure and predissociation dynamics studied using absorption spectroscopy and ion imaging." Thesis, University of Bristol, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364886.
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Kurtz, Joe. "UV-visible and infrared spectroscopy of carbon cluster molecules in solid argon." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184922.
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The UV-visible absorption spectrum of carbon vapor trapped in solid argon at low temperature contains many intense features, but only those of C₂ and C₃ have been identified. For this work, graphite vapor was produced under high vacuum conditions and condensed with argon onto a cold (∼10K) substrate. The resulting matrix-isolated carbon molecules were analyzed with both UV-visible and infrared absorption spectroscopy. Slight warming of the sample allowed formation of larger molecules and subsequent spectra traced the growth of their absorption features. The experiment associated infrared features to particular UV-visible features via their growth curves. The most reliable correlations are listed below. Theoretical calculations of equilibrium geometries and IR vibrational frequencies were performed on linear and nearly linear carbon chain molecules from C₃ to C₉ at the HF/SCF level of theory and from C₃ to C₇ at the MP2 level of theory, both using the 6-31G* basis set. Tentative assignment of the UV-visible features to molecules was made based on these considerations and on the following: the experimental IR/UV-visible correlations, previous experimental IR work, and modeling of the growth of the UV-visible features during matrix annealing. (UNFORMATTED TABLE FOLLOWS:) Molecule, UV-visible Feature (Å), IR Feature (cm⁻¹), Correlation Coefficient. C₃ (linear), 4100, 2040, .98. C₈ (linear), 3075, 1998, .97. C₈ (cyclic), 3900, 1804, .90. C₆ (linear), 2465, 1952, .86. C₇, 3480. C₉, 4480.
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Kuriger, Daniel W. "Absolute calibration techniques for UV spectroscopy based upon platinum emission line spectra." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA401450.
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Thesis (M.S. in Applied Physics) Naval Postgraduate School, Dec. 2001.Thesis advisors: D. Scott Davis, Richard Harkins. "December 2001." Includes bibliographical references (p. 65). Also available online.
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Mavadat, Maryam. "Characterization of biomedical used plasmas by IR and UV-VIS emission spectroscopy." Thesis, Université Laval, 2014. http://www.theses.ulaval.ca/2014/30780/30780.pdf.
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La modification de surface par plasma est une technique largement utilisée pour améliorer les propriétés de surface de polymères par le greffage de différents groupes fonctionnels. Dans ce projet de recherche, différentes méthodes pour améliorer les techniques de caractérisation de décharge micro-ondes de N2 et N2-H2 ont été étudiées dans le but d’optimiser le procédé de traitement de surface par plasma. Tout d'abord, un certain nombre de paramètres du plasma ont été mesurés à différentes conditions de traitement. Pour déterminer les paramètres du plasma, la spectroscopie d'émission optique a été utilisée dans la région l’ultraviolet, du visible et l’infrarouge (rarement utilisée dans la littérature scientifique). L’utilisation de la spectroscopie d'émission dans cette dernière région spectrale est avantageuse car elle permet d'éliminer les forts chevauchements entre les transitions atomiques et moléculaires et de pallier la faible intensité du signal observée dans la région de l’ultraviolet et du visible. Par la suite, la composition chimique de surface du PTFE a été analysée par XPS pour déterminer les concentrations en carbone, fluor, azote et des groupements amine suite à un traitement par plasma. Les résultats mentionnés ci-dessus ont été utilisés pour corréler les conditions de traitement et les paramètres de décharge micro-ondes à la composition chimique du PTFE modifié, dans l’objectif de mettre en évidence les paramètres expérimentaux du plasma et les espèces présentes dans le plasma qui jouent un rôle clé pour maximiser la fonctionnalisation de surface du polymère avec des groupements amine. En outre, un modèle mathématique a été développé en utilisant la technique de régression PLS. Pour construire ce modèle, un ensemble de données de variables d'entrée contenant les conditions de traitement et les paramètres spectroscopiques du plasma et une matrice de réponse contenant les propriétés de surface du polymère ont été générées. La base de données obtenue a été utilisée pour établir la relation entre les paramètres du plasma, les conditions de traitement et la chimie de surface du film. Cela a finalement permis de prédire la composition chimique de la surface à partir d’informations relatives au plasma, sans avoir à effectuer des analyses de surface après le traitement.Plasma surface modification is a widely used technique for improving the surface properties of polymers through the introduction of different functional groups. In the current research project, different methods to improve the characterization techniques of N2 and N2-H2 microwave discharge were investigated with the aim of optimizing the plasma surface process. First of all, a number of plasma parameters were measured at different process conditions. To determine the plasma parameters, optical emission spectroscopy was used not only within the well-documented UV-Visible region but also within the rarely studied infrared zone. Using infrared optical emission spectroscopy is advantageous as it eliminates the strong overlap between atomic and molecular transitions as well as the low intensity UV-Visible emission spectroscopy limitations. In the next step, the PTFE surface chemical composition was analyzed via XPS to quantify the concentrations of carbon, fluorine, and nitrogen after a plasma treatment in a N2-H2 gaseous environment. The XPS analyses were also performed after chemical derivatization to quantify the surface concentration of amino groups (%NH2) at different process conditions. The above-mentioned results were used to correlate process conditions and microwave N2-H2 discharge parameters to the chemical composition of the modified PTFE. The purpose was to determine the external plasma parameters and species present within the plasma which play a key role in the introduction of amino groups to the polymer surface. Furthermore, a mathematical model was developed using the Partial Least Squares Regression, (PLSR) using custom scripts written in MATLAB. A data set of input variables including the process conditions and plasma parameters for each experiment were generated along with the corresponding response matrix which in turn contained the surface properties of the film. The resulting database was used to build the relationship between the plasma parameters, process condition and the resulting film surface chemistry. This ultimately enabled to predict the PTFE surface chemistry from data originating from the plasma, without having to proceed to post-plasma surface characterization.
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Bernard, David. "Etude des émissions thermosphériques des planètes telluriques pour la caractérisation d'exoplanètes." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENY020/document.
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Depuis la découverte de la première exoplanète en 1995 par Mayor et Queloz, le nombre de planètes extrasolaires découvertes n'a cessé d'augmenter, pour dépasser les 1000 planètes à la fin de l'année 2013. Depuis le début des années 2000, la détection s'est accompagnée d'une volonté de caractérisation de l'atmosphère des exoplanètes. Les méthodes utilisées jusqu'ici sont la spectroscopie de transit primaire et l'étude des émissions thermiques en transit secondaire ou via l'étude des courbes de phase. L'objet de cette thèse s'inscrit dans cette recherche de caractérisation des atmosphères exoplanétaires, en s'intéressant à une méthode jusqu'ici inexplorée : l'analyse des émissions thermosphériques, i.e. les émissions de la haute atmosphère induites par les entrées énergétiques, flux extrême UV de l'étoile hôte et précipitations électroniques principalement. La première partie de cette thèse s'intéresse aux émissions thermosphériques de la Terre primitive avec une approche basée sur la modélisation. Le but étant la détermination des différentes émissions de la Terre à travers son histoire, afin de disposer de proxies pour la recherche et la caractérisation d'exoplanètes telluriques. Dans un premier temps nous avons calculé l'émission de l'atmosphère primordiale de la Terre irradiée par le Soleil jeune dans la raie Lyman Alpha. Nous avons montré que la raie planétaire, principalement formée par diffusion cohérente, montre un rapport d'émission avec le Soleil de l'ordre de 10-8, inaccessible aux observations, avec les instruments actuels ou de prochaine génération. Ce premier résultat nous à conduit à étudier la faisabilité d'une méthode indirecte de détection d'une couronne dense d'hydrogène autour d'une planète tellurique possédant une atmosphère de CO2 par les émissions des sous-produits de dissociation et d'ionisation de CO2. Les calculs menés sur la raie verte de l'oxygène (état O1S) et le doublet UV de CO2+ (état B2Σu+) ont montré que ces émissions présentaient des contrastes de l'ordre de 10^-12 avec le Soleil dans le cas d'une Terre primitive, et de l'ordre de 10^-6-10^-8 pour une planète tellurique proche d'une naine M. La conclusion générale des ces investigations est que les raies fines (atomiques ou moléculaires) des émissions thermosphériques sont trop faibles pour être détectées par les instruments actuels. Une voie possible serait l'étude des bandes d'émission moléculaires, qui nécessite une meilleure compréhension de la distribution en intensité des différentes bandes à travers le spectre, compréhension qui passe par l'étude expérimentale de ces émissions. C'est dans ce cadre que se situe la deuxième partie de cette thèse, qui s'intéresse à l'analyse spectroscopique de la Planeterrella, simulateur d'aurores boréales initialement développé à des fins pédagogiques. Nous avons réalisé une étude spectroscopique à basse et haute résolution de l'air, afin de caractériser les émissions présentes dans l'expérience d'une part, et aussi de disposer d'un spectre de référence qui servira à terme de test pour un code Monte Carlo développé pour étudier le dispositif expérimental, la caractérisation du dispositif constituant une étape nécessaire pour faire de la Planeterrella un objet d'étude scientifique. Enfin, la spectroscopie basse résolution du CO2 a été réalisée, avec des applications potentielles à MarsSince the discovery of the first exoplanet in 1995 by Mayor and Queloz, the number of extrasolar planets discovered has continuously grown up, to overtake 1000 planets at the end of 2013. Since the beginning of the 2000's, came with the detection the will to characterize the atmospheres of these exoplanets. Until now, the methods used are the primary transit spectroscopy and the study of the thermal emissions in secondary transit or using phase curves. The purpose of this thesis belongs to that search for characterizing exoplanetary atmospheres, by looking at a method unexplored until now: the study of the thermospheric emissions, i.e. emissions from the upper atmosphere induced by the energetic entries, mainly the extreme UV flux and the electronic precipitations. The first part of this thesis concerns the thermospheric emissions of the primitive Earth with an approach based on modeling. The goal is the determination of the several emissions of the Earth through its history in order to have proxies for the search and the characterization of telluric exoplanets. Initially we calculated the emission of the primary atmosphere of the early Earth under the young Sun in the Lyman Alpha line. We showed that the planetary line in mainly due to coherent diffusion and that the emission ratio between the planet and the Sun in this line is of about 10-8, far from the capabilities of current or next generation instruments. This first result lead us to study the feasibility of an indirect method to infer the presence of dense hydrogen corona surrounding a telluric planet with a CO2-dominated atmosphere, by studying its influence on the emissions of two CO2 by-products. The calculations carried out on the oxygen green line (O1S state) and the UV doublet of CO2+ (B2Σu+ state) showed that theses emissions present contrasts of about 10^-12 with the young Sun in the case of a primitive Earth, and of about 10^-6-10^-8 for a close-in telluric planet around a M dwarf. The general conclusion of the investigations is that the thermospheric emissions of thin (atomic or molecular) lines are too weak to be detected. A possible way could be the study of the molecular bands, of which emissions need to be better understood, especially concerning the intensity distribution of the several bands through the spectrum. This comprehension implies experimental studies of these emissions. The second part of this thesis lies in this scope and concerns the spectroscopic analysis of the Planeterrella, an aurora borealis simulator initially designed for outreach purpose. We made a spectroscopic study at low and high resolution with air, in order to characterize the emissions existing in the experiment, and also to have a reference spectrum which will be a final test for a Monte Carlo code developed to study the experimental device, the characterization of this device being a necessary step for the Planeterrella to become suitable for scientific purpose. Finally, we made a low resolution spectroscopic study of carbon dioxide, with potential applications to Mars
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Yazdi, Youseph. "Application of fluorescence and UV resonance Raman spectroscopy to the diagnosis of neoplastic changes in cytological specimens /." Digital version accessible at:, 1997. http://wwwlib.umi.com/cr/utexas/main.
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Toh, Shin Yi. "Conformational and UV photochemistry studies of amino acids in matrix-isolation FTIR spectroscopy." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58582.
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Rüger, Robert, Thomas Niehaus, Lenthe Erik van, Thomas Heine, and Lucas Visscher. "Vibrationally resolved UV/Vis spectroscopy with time-dependent density functional based tight binding." AIP Publishing, 2016. https://ul.qucosa.de/id/qucosa%3A21502.
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We report a time-dependent density functional based tight-binding (TD-DFTB) scheme for the calculation of UV/Vis spectra, explicitly taking into account the excitation of nuclear vibrations via the adiabatic Hessian Franck-Condon method with a harmonic approximation for the nuclear wavefunction. The theory of vibrationally resolved UV/Vis spectroscopy is first summarized from the viewpoint of TD-DFTB. The method is benchmarked against time-dependent density functional theory (TD-DFT) calculations for strongly dipole allowed excitations in various aromatic and polar molecules. Using the recent 3ob:freq parameter set of Elstner’s group, very good agreement with TD-DFT calculations using local functionals was achieved.
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Lai, Sin Pin. "Furan measurement in transformer oil by UV-Vis spectroscopy using fuzzy logic approach." Thesis, Curtin University, 2009. http://hdl.handle.net/20.500.11937/2342.
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An Ultraviolet to Visible (UV-Vis) spectroscopic analysis based on fuzzy logic approach has been developed for furan content measurement in transformer oil. Following the successful identification and quantification of furan derivatives in transformer oil by ASTM D5837 standard, the new approach is able to approximate the furan content more conveniently and economically. As furan concentration level would determine the absorption intensity in UV-Vis spectral range, the fuzzy logic software model developed would exploit this characteristic to aggregate the furans content level in transformer oil. The UV-Vis spectral response at other ambient temperature is also studied. The proposed technique provides a convenient alternative to conventional method of furan measurement by High Performance Liquid Chromatography (HPLC) or Gas Chromatography Mass Spectrometry (GC/MS) in ASTM D5837 Standard.
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Lai, Sin Pin. "Furan measurement in transformer oil by UV-Vis spectroscopy using fuzzy logic approach." Curtin University of Technology, Department of Electrical and Computer Engineering, 2009. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=128452.
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An Ultraviolet to Visible (UV-Vis) spectroscopic analysis based on fuzzy logic approach has been developed for furan content measurement in transformer oil. Following the successful identification and quantification of furan derivatives in transformer oil by ASTM D5837 standard, the new approach is able to approximate the furan content more conveniently and economically. As furan concentration level would determine the absorption intensity in UV-Vis spectral range, the fuzzy logic software model developed would exploit this characteristic to aggregate the furans content level in transformer oil. The UV-Vis spectral response at other ambient temperature is also studied. The proposed technique provides a convenient alternative to conventional method of furan measurement by High Performance Liquid Chromatography (HPLC) or Gas Chromatography Mass Spectrometry (GC/MS) in ASTM D5837 Standard.
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Carroll, Joshua Adam. "Eye-safe UV stand-off Raman spectroscopy for explosive detection in the field." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/80879/1/Joshua_Carroll_Thesis.pdf.
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This project focused on maximising the detection range of an eye-safe stand-off Raman system for use in detecting explosives. Investigation of the effect on detection range through differing laser parameters in this thesis provided optimal laser settings to achieve the largest possible detection range of explosives, while still remaining under the eye-safe limit.
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Sommer-Marquez, Alicia Estela. "Retención de clorofila en Hidrotalcitas." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2013. http://www.theses.fr/2013ENCM0002/document.
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Dans les expériences modélisant la photosynthèse, une bonne dispersion des molécules de chlorophylle est requise. Afin d'obtenir cette bonne dispersion, une solution consiste à les ancrer à un hôte. Dans cette étude, des nouveaux matériaux hybrides sont synthétisés en utilisant des hydrotalcites et un dérivé de la chlorophylle : la chlorophylline. La chlorophylline est incorporée et dispersée dans les hydrotalcites par co-précipitation ou pendant la reconstruction des hydrotalcites. Dans cette thèse est également discuté l'effet d'une irradiation par micro-onde. Dans tous les cas sont obtenus des matériaux stables, où les molécules de chlorophylline sont isolées et liées aux hydrotaltices par des liaisons avec les groupes hydroxy OH. Dans ce travail, de nouveaux matériaux sont synthétisés en utilisant les hydrotalcites et la chlorophylle a. Dans ce cas là, il est mis en valeur que la stabilisation de la chlorophylle a peut dépendre du support, à la fois par la nature et le rapport des métaux constituants les hydrotalcites. Ces matériaux hybrides obtenus (chlorophylle a/hydrotalcites) sont également stables. Ces matériaux ont été testés par lixiviation à l'acétone. Dans tous les cas, les composés lixiviés sont de la chlorophylle a, montrant ainsi que la nature et la composition des molécules sont préservées même après trente jours, bien qu'il soit à noter que dans le cas des hydrotalcites Ni/Al une faible fraction de la chlorophylle est décomposée en phéophytine. Finalement, bien que les hydrotalcites soient des composés relativement simples, ils s'avèrent tout à fait adaptés pour empêcher la dégradation des molécules de chlorophylleIn experiments modeling photosynthesis, well dispersed chlorophyll molecules are required. A solution could be to anchor them on some host. In this work, new hybrid materials are synthesized using hydrotalcite and a chlorophyll derivative : chlorophyllin. Chlorophyllin is incorporated and dispersed in hydrotalcite through simultaneous precipitation or during hydrotalcite reconstruction. The effect of microwave irradiation on the crystallization step is discussed. In all cases stable materials are obtained, chlorophyllin molecules are isolated and bonded through hydrotalcite OH groups. Also new hybrid materials are synthesized using hydrotalcites and chlorophyll a. The effect of the support composition on chlorophyll a stabilization is discussed. The stability of the adsorbed chlorophyll a is affected by the support nature and the metal ratio of the hydrotalcite. The obtained hybrid compounds (chlorophyll a on hydrotalcite) are stable. Those hybrids were tested in lixiviation with acetone. In all cases, the lixiviated compound was chlorophyll a showing that the composition and nature of the molecule was preserved even after thirty days, although Ni/Al hydrotalcites decomposed a small fraction of the chlorophyll to pheophytin. Hydrotalcites being basic compounds turn out to be an adequate material to avoid degradation of chlorophyll molecules
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Boutry, Céline. "Échanges de matière et d'énergie dans la couronne solaire : des régions actives aux nanoflares." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112017.
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Le chauffage de la couronne et la formation du vent solaire sont plus que jamais d'actualité en astrophysique stellaire. En ce qui concerne le vent solaire, nous avons cherché à vérifier l'hypothèse selon laquelle il est issu des frontières de régions actives. En combinant l'imagerie en rayons X et Extrême Ultra Violet (EUV), la spectroscopie EUV et les mesures de champ magnétique longitudinal au niveau de la photosphère, nous avons développé une technique d’estimation quantitative des échanges de masse entre deux régions actives. Nous avons ainsi montré que cet échange n'est pas négligeable devant le flux de matière participant au vent solaire. Une attention particulière a été apportée aux traitements des données spectroscopiques notamment en ce qui concerne la référence en longueur d'onde. En effet, celle-ci est cruciale pour déterminer les vitesses y compris leurs signes dans les échanges. Sur la thématique des micro-événements de chauffage, nous avons développé une méthode de détection à partir d'images prises à haute cadence en rayons X. A l'aide de données spectroscopiques, nous avons pu estimer les vitesses Doppler et l’élargissement Doppler des raies dans les événements et les comparer au reste du champ de vue. Nous en avons déduit l’énergie contenue dans les vitesses non résolues, susceptible de contribuer au chauffage, qui s’avère être comparable aux pertes radiatives observées dans les régions activesThe coronal heating and the formation of the solar wind are one of the core issues in stellar astrophysics.Concerning the solar wind, we have undertaken to verify the hypothesis that its origin is located at the borders of active regions. By combining X-ray and Extreme Ultra Violet (EUV) images, EUV spectroscopy and measurements of the longitudinal magnetic field at the photosphere, we have developed a technique for quantitatively estimating the mass exchange between two active regions. We have shown that this mass exchange is significant compared to the flow of material involved in the solar wind. Particular attention was paid to the analysis of spectroscopic data and more specifically the issue of reference wavelength. Indeed, it is crucial to determine the speeds including their signs in the exchange. On the topic of heating micro-events, we have developed a method for detecting micro-events from high-cadence X-ray images. With the help of spectroscopic data, we have been able to estimate the Doppler velocities and Doppler broadening of the lines in the events and compare them to the rest of the field of view. We derived the energy in the unresolved velocities, which can contribute to the heating, which turns out to be comparable to the radiative losses observed in active regions
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Holen, Henrik Waldal. "Structural and biochemical insights into mammalian cobalt-substituted methionine sulfoxide reductase B1 using UV-visible spectroscopy and high-resolution NMR spectroscopy." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bioteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16825.
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Prior to this study it was discovered that MsrB1 from Mus musculus expressed in Escherichia Coli binds cobalt(II) (hereafter cobalt) in cobalt-supplemented growth media, and it had further been demonstrated that the His-tag was not responsible for this metal uptake. The aim of this study was to investigate the effects of cobalt on the growth of E. Coli in culture, characterize the metal-uptake and metal-binding site of cobalt-substituted MsrB1 by UV-visible spectroscopy and to gain structural information about the protein by high resolution NMR spectroscopy.The effects of cobalt on growth of E. Coli were studied by growing cultures in Lysogeny broth (LB) and minimal (M9)-media supplemented with different concentrations of cobaltdichloride (CoCl2) and monitoring culture growth by optical density (OD) measurements. Growth rates were found to decrease with increasing concentrations of CoCl2. To study the cobalt-uptake of MsrB1, the protein was recombinantly expressed in E. Coli in different cobalt-supplemented growth media, and the purified protein analyzed by UV-vis spectroscopy. Cobalt-uptake was demonstrated in all cases by characteristic absorption peaks owing to the cobalt-ligand complex, and the wavelengths of these peaks matched those of a tetrahedral four-coordinated cobalt-Cys complex. It was argued that these four Cys residues should be the same that constitute the zinc(II)-binding site of MsrB1, indicating that cobalt simply replaces zinc as a structural metal ion in cobalt-substituted MsrB1 (Co-MsrB1). It was argued that the intracellular concentration of cobalt in E. Coli should be significantly higher than zinc, and that this together with similar ionic radii for cobalt and zinc leads to the formation of Co-MsrB1. MsrB1 expressed in nickel(II)-supplemented LB did not lead to formation of Ni-MsrB1, which was argued to result from nickel not being released directly into the cytosol in E. Coli. Co-MsrB1 was produced by zinc-starvation of E. Coli followed by expressing the protein in zinc-free minimal medium supplemented with CoCl2. To investigate if pH-titratable groups could be detected, the protein was dialyzed against buffers with pH 4.9-11.5 and the molar extinction coefficient was found from UV-vis absorption spectra in the different pH. Two titration curves were observed, but assignment of the titrations to specific residues could not be made. Further, Co- and Zn-MsrB1 was dialyzed against buffers with metal chelating agents to remove the metal ions from the two proteins. Cobalt was successfully removed at pH 5.0 and 5.5, while removal of zinc from Zn-MsrB1 was not detected, demonstrating that zinc is more tightly bound to the Cys-ligands than cobalt.To study the ratio of formation of Co-MsrB1 and the native zinc-form Zn-MsrB1 in CoCl2-supplemented growth media, the molar extinction coefficient of Co-MsrB1 was determined, and the concentration of Co-MsrB1 in purified protein samples from protein expression in different growth media was determined. The Co-MsrB1:Zn-MsrB1 ratio was found to be 0.2 in M9 medium supplemented with 10 µM CoCl2, 0.1 in LB supplemented with 50 µM CoCl2 and 0.03 in LB supplemented with 10 µM CoCl2. From 2D- and 3D-NMR experiments on 13C- and 15N-enriched Co-MsrB1, a 70 % backbone assignment and 50 % side chain-assignment was accomplished using Computer Aided Resonance Assignment (CARA). The four structural Cys-residues of the native protein was not found, while the other three Cys-residues of MsrB1 were assigned, confirming that the same Cys-residues are responsible for coordination of cobalt and zinc in MsrB1. Many strongly shifted signals were observed in 1D 1H spectra of Co-MsrB1, some as far upfield as 350 ppm and downfield as -80 ppm, and it was argued that most of the unassigned residues should be found outside the spectral width of the 2D and 3D-NMR spectra.To gain further structural information about Co-MsrB1, pseudocontact shifts (PCSs) were determined for the assigned HN-atoms of Co-MsrB1 by using the published chemical shifts of for Zn-MsrB1. The PCSs were analyzed by AnisoFit using three conformers and the mean conformer of the published Zn-MsrB1 structure, and the best correlations between observed and calculated PCSs were found for conformer 3. The PCSs were plotted against their hypothetical distance to cobalt using the structure of Zn-MsrB1, and a very good PCS-distance proportionality was found, indicating that Co-MsrB1 and Zn-MsrB1 have the same overall fold and structure. The AnisoFit calculations and PCSs of the N-terminus suggested that the N-terminus spends significant time in the proximity of the metal-binding site, and it was argued that this proximity ensures high catalytic efficiency due to the short distance between the catalytic and resolving Cys-residues.
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Caló, A. (Antonio). "Electron spectroscopy of atoms and molecules using synchrotron radiation, UV radiation and electron impact." Doctoral thesis, University of Oulu, 2007. http://urn.fi/urn:isbn:9789514286650.
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Abstract
The present thesis investigates the electronic structure of selected atoms and molecules in vapor phase. Electron spectroscopy is applied for studying the electronic transitions following excitation and ionization with electron and photon bombardment. The work focuses on the photoionization and Auger decay of selected noble gasses, and on the photoionization and Auger decay of core ionized or resonant excited alkali halide molecules. The experimental results are compared with theoretical predictions.
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Kranert, Christian. "Investigation of wide-bandgap semiconductors by UV Raman spectroscopy: resonance effects and material characterization." Doctoral thesis, Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-160062.
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Die vorliegende Arbeit befasst sich mit der Untersuchung von weitbandlückigen Halbleitern mittels Raman-Spektroskopie. Diese wurde vorwiegend unter Verwendung von Licht einer Wellenlänge von 325 nm im ultravioletten Spektralbereich angeregt. Damit konnten zum einen aufgrund eines erhöhten Streuquerschnittes Messungen zur Probencharakterisierung durchgeführt werden, die mit Anregung im sichtbaren Spektralbereich nicht möglich gewesen wären. Zum anderen wurden bei dieser Anregungswellenlänge auftretende Resonanzeffekte untersucht. Dabei werden zwei verschiedene Materialsysteme behandelt: zum einen Kristalle mit Wurtzitstruktur und zum anderen binäre und ternäre Sesquioxide mit Metallionen der III. Hauptgruppe.
An den Kristallen mit Wurtzitstruktur wurde die Streuung des Anregungslichts mit Energie oberhalb der Bandlücke an longitudinal-optischen (LO) Phononen untersucht. Die Streuung an einzelnen LO-Phononen wird unter diesen Anregungsbedingungen von einem Prozess dominiert, der eine elastische Streuung beinhaltet, durch die die Impulserhaltung verletzt wird. Es wurde ein Modell aufgestellt, dass zwischen einer elastischen Streuung an der Oberfläche und an Punktdefekten unterscheidet, und mit Hilfe von Experimenten verifiziert. Weiterhin wurde der Einfluss von Ladungsträgern auf die Energie der LO-Phononen untersucht und es wird eine Anwendung dieser Erkenntnisse zur Charakterisierung der Oberfläche von Zinkoxid vorgestellt.
An den binären Oxiden des Galliums und Indiums wurden die Energien der Phononenmoden ermittelt und die resonante Verstärkung bei der verwendeten Anregungswellenlänge untersucht. Für das Galliumoxid wurde dabei insbesondere die Anisotropie des Materials berücksichtigt. Für das Indiumoxid wird dargestellt, dass durch die resonante Anregung alle Phononenmoden beobachtet werden können, was insbesondere auch die Bestimmung der Phononenmoden von Dünnschichtproben ermöglicht. Weiterhin waren Mischkristalle des Galliumoxids Untersuchungsgegenstand, in denen das Gallium teilweise durch Indium oder Aluminium ersetzt wurde. Die Phononenenergien wurden in Abhängigkeit der Zusammensetzung ermittelt und der Einfluss von strukturellen Eigenschaften darauf sowie das Auftreten von Phasenübergängen untersucht.
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Miller, Jeff. "On the possibility of detecting low barrier hydrogen bonds with UV spectroscopy and kinetic measurements /." Electronic version (PDF), 2004. http://dl.uncw.edu/etd/2003/millerj/jeffmiller.pdf.
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Holland, Torrey. "VIBRATIONAL SPECTROSCOPY ANALYSES OF THE DEGRADATION AND CONTAMINATION OF ENGINE OIL LUBRICANTS COUPLED WITH MULTIPLE SPECTROSCOPIC TECHNIQUES." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2399.
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The spectral analysis techniques afforded us from the field of physics has enabled us to explore the spectral signatures of trace contaminants and degradation products in used or in service engine oil through atomic and molecular spectroscopy. Here we have examined the need to address proper preparation of calibrating samples for infrared spectroscopy analysis by inducing emulsification and have evaluated multiple procedures for proper emulsification of samples with the intent to help establish the protocols that are not explicitly set forth in the ASTM International standard. We have also explored the use of Fourier-transform infrared spectroscopy techniques to examine the suppression of the O–H stretching mode of water due to the influence of ethylene glycol, which may help in the quantification of water when both are present in oil. This was done in conjunction with exploring alternative methods for direct and indirect measurement of the glycol contamination by use of UV/Vis spectroscopy, Raman, and laser-induced breakdown spectroscopy. An exploration of FT-IR and UV/Vis data on the oxidation of oil by means of ANOVA calculations has led to the reporting of highly significant differences in the data of differing oxidation times and in regions of the spectrum not known to have been previously reported.
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Bradshaw, John Thomas. "BROADBAND COUPLING INTO SINGLE MODE, PLANAR INTEGRATED OPTICAL WAVEGUIDE STRUCTURES FOR SPECTRAL ANALYSIS OF THIN FILM ANALYTES AND INTERFACIAL CHEMICAL ENVIRONMENTS." Diss., Tucson, Arizona : University of Arizona, 2005. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1144%5F1%5Fm.pdf&type=application/pdf.
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Hande, Aniket A. "Nano-graphènes paramagnétiques - dérivés des radicaux de Blatter." Thesis, Pau, 2021. http://www.theses.fr/2021PAUU3001.
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Cette thèse décrit la synthèse et la caractérisation de la structure électronique du 2-phényl-3H- [1,2,4] triazino [5,6,1-kl] phénoxazin-3-yle (radical Blatter planaire) et de ses dérivés par Ultra-Violet spectroscopie photoélectronique (UV-PES). La première partie décrit la synthèse et la structure électronique du radical Blatter et une série de dérivés substitués en C (10) de radicaux Blatter planaires contenant des substituants H, F, Cl, Br, CN, CF3 et OMe a été étudiée par spectroscopie UV photoélectronique en phase gazeuse. Les radicaux ont également été analysés par résonance paramagnétique électronique, UV vis et méthodes électrochimiques. L'interprétation des spectres de photoélectrons a été soutenue par des calculs quantiques utilisant la méthode DFT CAM-B3LYP / 6-311G (d, p). L'analyse comparative des énergies d'ionisation théorique et expérimentale est présentée. La deuxième partie du manuscrit traite de l'effet de l'expansion du système et de délocalisation de la délocalisation de spin sur les radicaux Blatter planaires contenant des anneaux de naphtalène, de phénanthrène et de pyrène. La structure électronique de ces radicaux a été étudiée par spectroscopie UV-photoélectronique et comparée aux résultats de calcul DFT obtenus au niveau de théorie CAM-B3LYP / 6-311G (d, p). La dernière partie présente quelques transformations de groupes fonctionnels pour les dérivés substitués en C (10) des radicaux Blatter planaires et leurs caractérisations spectroscopiques et électrochimiques, ainsi qu'une description de chimie physique étudiée par ordinateurThis thesis describes the synthesis and electronic structure characterization of 2-phenyl-3H-[1,2,4]triazino[5,6,1-kl]phenoxazin-3-yl (planar Blatter radical) and its derivatives by Ultra-Violet photoelectron spectroscopy (UV-PES). First part discribes synthesis and electronic structure of Blatter radical and a series of C(10)-substituted derivatives of planar Blatter radicals containing H, F, Cl, Br, CN, CF3 and OMe substituents was investigated by gas phase UV-photoelectron spectroscopy. The radicals were also analyzed by electron paramagnetic resonance, UV vis and electrochemical methods. The interpretation of photoelectron spectra was supported by quantum calculations using DFT CAM-B3LYP/6-311G(d,p) method. The comparative analysis of theoretical and the experimental ionization energies are presented. The second part of the manuscript deals with the effect of expansion of the -system and increased spin delocalization on the planar Blatter radicals containing naphthalene, phenanthrene and pyrene rings. The electronic structure of these radicals ware investigated by UV-photoelectron spectroscopy and compared to DFT computational results obtained at the CAM-B3LYP/6-311G(d,p) level of theory. The final part presentes some functional group transformations for C(10)-substituted derivatives of planar Blatter radicals and their spectroscopic and electrochemical characterizations, as well as computationally studied physical chemistry description
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Krebs, Nils [Verfasser], and Eberhard [Akademischer Betreuer] Riedle. "New insights for femtosecond spectroscopy : from transient absorption to 2-dimensional spectroscopy in the UV spectral domain / Nils Krebs. Betreuer: Eberhard Riedle." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2013. http://d-nb.info/1045152978/34.
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Kyriaki, Kosma. "UV-pump IR-probe Spectroscopy of Molecules with Time-Resolution reaching the 10-fs Range." Diss., lmu, 2008. http://nbn-resolving.de/urn:nbn:de:bvb:19-92803.
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Gong, Donglai 1977. "Quasar spectroscopy in UV and X-ray- probing the intergalactic medium using helium and oxygen." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/30116.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Physics, 2004.Includes bibliographical references (p. 89-97).
We employ ultraviolet (UV) and X-ray quasar spectroscopy to study the physical state of the Intergalactic Medium (IGM). First, we quantify the possibility of measuring the temperature of moderately over-dense regions of the IGM at high redshift (z [approx.] 2) using the strongest resonant absorption lines of neutral hydrogen ([lambda]HI = 1215.67 A[ngstroms]) and neutral helium ([lambda]HeI = 584.33 A[ngstroms]). We calculate the fraction of neutral helium in the IGM at z [approx.] 2 by solving a set of photoionization equilibrium equations. Using known distributions of the redshift, column density and Dopper [beta]-parameter of Lyman-[alpha] ac lines, we perform Monte Carlo simulation to create a line list, from which we calculate the number of observable HeI lines. We expect that 4.5% of the HI lines have observable HeI counterparts. Future ultraviolet (UV) telescope with wavelength coverage from 1400 A[ngstroms] to 2400 A[ngstroms] should be able to observe [approx.] 16 HelI lines per line of sight observation. Second, we analyze a combined 171 ksec. spectroscopic observation of the low redshift quasar 3C 273 by the Chandra X-ray Observatory. We search for the high ionization state lines of OVII and OVIII at redshifts of known intervening OVI absorbers. Detection of associated OVII or OVIII absorptions in the X-ray would suggest the existence of a warm hot component of the Intergalactic Medium at temperature T [approx.] 106 - 107 K. We observe an unresolved OVII line at z [approx.]0 with a maximum Doppler [beta] parameter of 190 km/s. We do not see any associated OVII absorption for a z [approx.] 0.12 OVI absorber at the -3.5[sigma] level. We provide most stringent to date (Chandra resolution limited) upper limit on the temperature of the z [approx.] 0.12 absorber and discuss the possibilities of photoionization and collisional ionization.
by Donglai Gong.
S.M.
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De, Brito Milena. "Investigation of interpenetrating polymer networks and recent UV curable chemistries." Thesis, Mulhouse, 2011. http://www.theses.fr/2011MULH5772/document.
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Le sujet de cette thèse concerne le développement et la caractérisation de résines photosensibles pour le prototypage rapide. L'étude a tout d'abord consisté à optimiser des systèmes photoréticulables commerciaux : systèmes hybrides acrylates/époxydes. La réactivité des différentes formulations préparées ainsi que leurs propriétés thermomécaniques ont pu être évaluées grâce à la spectroscopie infrarouge à transformée de Fourier résolue dans le temps (RT-FTIR) et par analyse mécanique dynamique (DMA). En parallèle, une étude plus fondamentale visant à mieux comprendre et à contrôler la formation de réseaux polymères interpénétrés simultanés méthacrylate/époxyde a été menée. L'influence de paramètres physico-chimiques tels que l'intensité lumineuse, la concentration en photoamorceur sur les propriétés finales du matériau a notamment été abordée. Ensuite, des résines dont la chimie est moins conventionnelle ont été considérées. Comme très peu de ces monomères sont disponibles commercialement, certains d'entre eux ont dû être synthétisés. Certaines formulations ont démontré non seulement une bonne réactivité mais aussi d'intéressantes propriétés thermomécaniques et une limitation du retrait de polymérisation. Finalement, une méthode de mesure du retrait linéaire simple et facile à mettre en œuvre a été mise en place afin de comparer les différents systèmes chimiques proposés au cours de la thèse. L'utilisation de cet outil est très appréciable car il pourrait permettre de choisir le type de formulations induisant le moins de retrait possible lors de la réalisation d'un objet couche par coucheThe aim of this thesis is to develop and characterize UV curable resins for rapid prototyping application. The study started with the optimization of commercially available hybrid acrylate/epoxide systems (IPNs) commonly used in this industrial field. The reactivity of the different tested formulations in conjunction with their thermomechanical properties have been assessed by means of Real time Fourier transform infrared spectroscopy (RT FTIR) and Dynamic mechanical analysis (DMA). In the meantime, a more academic study has been performed on an epoxide/methacrylate mixture in order to get a better understanding and a control of the IPN formation. The influence of the light intensity and the photoinitiator concentration on the final properties has been examined. Then, UV curable resins whose chemistry is less conventional have been considered. Owing to the lack of commercial availability of some monomers, time has been spent to synthesize them. Some formulations display promising features especially in terms of reactivity, thermomechanical properties and linear shrinkage. Finally, a simple method to measure linear shrinkage has been set up to compare the different systems proposed during the thesis and thus evidences the less shrinkable UV curable system
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Bajorek, Tom Werstiuk Nick H. "The UV photoelectron spectroscopy of transients : An experimental and computational investigation of electronic structure and reaction mechanisms /." *McMaster only, 2003.
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Kokkonen, E. (Esko). "Fragmentation of small molecules by UV and X-ray irradiation." Doctoral thesis, University of Oulu, 2017. http://urn.fi/urn:isbn:9789526216317.
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Abstract
Electron-ion coincidence spectroscopy has been used to study the fragmentation behaviour of small molecules in two distinct cases: to resolve the state specific fragmentation patterns of HgBr₂ and HgCl₂ subsequent to UV ionization, and to distinguish the dissociation behaviour of various chlorinated methanes (CH₃Cl, CH₂Cl₂, CHCl₃ and CCl₄) subsequent to X-ray irradiation. The mercury-compound work has revealed details on the electronic structure and dissociation dynamics of the valence states which were previously unknown. The study on the chlorinated methanes has found new details on the exact pathways of the appearance of a specific fragment and also investigates the speed of the dissociation in the four different chlorinated methane molecules. The results from the electron-ion coincidence spectroscopic experiments are presented and analysed together with theoretical and computational support.
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Adamov, Minja Gemisic. "Measurements of local electric fields by doppler-free laser spectroscopy of hydrogen resonance lines." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2007. http://dx.doi.org/10.18452/15576.
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In dieser Arbeit wurde eine einfache laserspektroskopische Messmethode für lokale elektrische Feldstärken im Hinblick auf ihre Messmöglichkeiten und -grenzen untersucht. Als empfindliche optische Feldsensoren dienen dabei Wasserstoffatome, für die die Stark-Aufspaltung der Spektrallinien im elektrischen Feld wohl bekannt und exakt berechenbar ist. Die experimentellen Untersuchungen wurden an einer Niederdruck-Gaszelle durchgeführt, in der ein elektrisch geheizter Wolframdraht für thermische Dissoziation von Wasserstoffmolekülen sorgte. Die Wasserstoffatome wurden durch zwei gegenläufige Laserstrahlen Doppler-frei angeregt. Die Durchstimmung der schmalbandigen Laserstrahlung über den Wellenlängenbereich der Zwei-Photonen-Resonanz lieferte direkt das vom elektrischen Feld hervorgerufene Stark-Spektrum des angeregten Zustands. Weil die Methode im Gegensatz zu ähnlichen, erheblich aufwendigeren Verfahren nur die niedrigsten Wasserstoff-Energieniveaus benutzt, die mit Zwei-Photonen-Anregung direkt aus dem Grundzustand erreichbar sind, kommt sie mit einem einzigen Laser aus. Für das erste angeregte Niveau mit n = 2 wird Strahlung bei 243 nm benötigt, das nächsthöhere Niveau mit n = 3 erfordert 205 nm. Für n = 2 wurden Untersuchungen an Wasserstoff und Deuterium durchgeführt und Stark-Spektren mittels optogalvanischer Detektion gemessen. Schwerpunkt der Arbeit waren aber die Messungen an Wasserstoff für n = 3, bei denen zusätzlich Balmer-alpha-Fluoreszenz im Sichtbaren zur Detektion eingesetzt werden konnte. Bei elektrischen Feldern bis 200 V/cm wurden Stark-Spektren für drei verschiedene Polarisationszustände der Laserstrahlung aufgenommen. Als Ergebnis konnte jeweils ein Paar isolierter Stark-Komponenten in den Spektren identifiziert werden, dessen gut messbarer Frequenzabstand durch Vergleich mit theoretischen Werten die Bestimmung der elektrischen Feldstärke ermöglicht.A method for electric field measurements that observes the Stark spectra of the low excited levels n = 2 and n = 3 of atomic hydrogen has been explored in this work. As advantage these levels can be excited Doppler-free from the ground state by a single laser and the highly resolved Stark spectra are easy to understand and to be calculated. Good sensitivity of electric field measurements is achieved with specially designed solid state laser systems, which provide tuneable pulsed UV radiation with a high pulse peak-power and a narrow bandwidth needed for Doppler-free two-photon excitation. Using hydrogen and deuterium the Stark spectra of the n = 2 level are detected as optogalvanic signal. For three different cases of laser polarization the n = 3 spectra of hydrogen are measured simultaneously with optogalvanic and laser induced Balmer alpha fluorescence detection. Electric fields down to 200 V/cm can be determined from the Stark spectra of n = 2 level, while the spectra of n = 3 level enable measurements of electric fields as small as 50 V/cm in each of the three cases of laser polarization.
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Rivas, Gildardo. "Ab initio calculations of optical constants from UV to X-rays /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/9629.
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Cagnin, Flavia [UNESP]. "Complexos heterobilantanídicos luminescentes sob excitação UV e raios X." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/126306.
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000774381.pdf: 5960727 bytes, checksum: 0ebf015f50f4bdcf797b4b89b7c40b61 (MD5)Neste trabalho, foram obtidos e caracterizados complexos luminescentes com íons Ln3+ (Ln = Eu, Gd, Tb, Dy) homo e/ou heterobilantanídicos com o ligante ácido tiofeno-2- carboxílico, que atua eficientemente como antena, absorvendo energia e transferindo-a para o íon emissor. A presença do anel tiofênico nos ligantes confere características interessantes, como por exemplo, maior polarizabilidade por conter em sua estrutura um átomo de enxofre. Os complexos foram caracterizados por análise elementar, análise de Ln3+ por análise titulométrica com uso de edta, análise térmica, espectroscopia vibracional na região do infravermelho e DRX, que permitiram propor as estequiometrias [Ln(α-tpc)3(α-Htpc)2]n e [Ln(α-tpc)3(α-Htpc)] e que a coordenação se dá pelo modo bidentado. Pelas espectroscopias eletrônica UV-vis, fotoluminescência e de excitação por raios X, foram observadas as transições características dos íons Ln3+ envolvidos neste trabalho. São propostos mecanismos de transferência de energia em compostos puros e nos complexos heterobilantanídicos, à partir da elaboração de diagramas de energia, baseados nos resultados de fotoluminescência. Os complexos também tiveram suas propriedades magnéticas investigadas, em alguns casos, pela utilização da técnica de EPR, PPMS e VSM, sendo observado um comportamento predominantemente paramagnético para os complexos. Os complexos foram expostos à radiação ionizante por um tempo prolongado, a fim de verificar o comportamento e estabilidade química desses complexos homo e heterolantanídicos sob radiação ionizante e os resultados mostraram que os complexos são estáveis frente à excitação com raios-X.
Monometallic and/or heterobimetallic Ln3+ (Ln = Eu, Gd, Tb, Dy) luminescent complex with thiophen-2-carboxylic acid was investigated. The ligand employed in this work, acts efficiently as antenna, absorbing and transfer energy to the emitter ion. The thiophen ring provides interesting features to the system, like higher polarizability due the sulphur atom. The complex were characterized by elemental analysis, complexometric titrimetry with edta, in order to quantify Ln3+, thermal analysis, FTIR and XRD which allowed propose two different stoichiometries [Ln(α-tpc)3(α-Htpc)2]n and [Ln(α-tpc)3(α-Htpc)] and the coordination of the ligand to the Ln3+ occurs through the bidentate coordination mode. By the UV-vis, photoluminescence and X rays spectroscopies, were observed the Ln3+ transitions. Energy transfer mechanism were proposed in monometallic and heterobimetallic complexes, from the drafting of the energy diagram, based on results of fotoluminescence. The complex also have the magnetic properties investigated, by the EPR, PPMS and VSM techniques and the results shows a predominantly paramagnetic behavior to the complexes. The complexes were exposure to ionizing radiation during a extended time, in order to verify the chemical stability of the homo and hetero-lanthanide complex forward to ionizing radiation and is observed high stability over X-ray excitation.
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Martin, Philip Nathaniel. "Measurements of atmospheric trace gases using open path differential UV absorption spectroscopy for urban pollution monitoring." Thesis, Imperial College London, 2003. http://hdl.handle.net/10044/1/11299.
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Schwalb, Nina K. [Verfasser]. "Ultrafast electronic deactivation dynamics in DNA model systems by femtosecond UV fluorescence spectroscopy / Nina K. Schwalb." Kiel : Universitätsbibliothek Kiel, 2009. http://d-nb.info/1019867485/34.
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Ash, Andrew David. "Experimental astrophysics with magnetised laser-produced plasma : UV/X-ray spectroscopy, interferometry and pulsed magnetic fields." Thesis, University of York, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428050.
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de, La Harpe Kimberly Desneiges. "Femtosecond UV and Infrared Time-Resolved Spectroscopy of DNA: From Well-ordered Sequences to Genomic DNA." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1299527926.
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