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Zamotaeva, Valeriya. "High-resolution FTIR spectra analysis of sulfur dioxide isotopologues." Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCK053.
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Dans cette thèse, nous avons examiné les propriétés spectrales de l’anhydride sulfureux. Les spectres FTIR expérimentaux de nombreux isotopologues du dioxyde de soufre, 32S16O2, 34S16O2, 32S18O2 et 32S16O18O, ont été enregistrés pour la première fois dans les régions des bandes fondamentales, «chaudes», harmoniques et de combinaison. La grande variabilité des conditions expérimentales a permis d’observer et d’identifier pour la première fois des transitions appartenant aux ban¬des ro-vibrationnelles suivantes : 3v2, 3v2 - v2, 2v2 - v2 bandes de 32S16O2 ; 2v2 - v2 bande de 34S16O2 ; v1 + v2, v2 + v3, v1 + v3, 2v1, 2v3 bandes de 32S18O2 ; v1, v3, 2v1, v1 + v3, 2v3 bandes de 32S16O18O. Les problèmes spectroscopiques inverses ont été résolus pour les états étudiés avec une déviation «rms» comparable à l’incertitude expérimentale. Suite à cette analyse, environ 38 000 transitions ro-vibrationnelles appartenant à 17 états vibratoires excités ont été identifiées pour la première fois. Les données très précises obtenues sur tous les isotopologues du dioxyde de soufre ont été utilisées pour corriger les paramètres de la IPF<br>In this thesis we considered the spectral properties of the sulfur dioxide. The experimental FTIR spectra of numerous sulfur dioxide isotopologues, 32S16O2, 34S16O2, 32S18O2 and 32S16O18O, were first recorded in the regions of fundamental, «hot», combination and overtone bands. The wide variability of the experimental conditions gave possibility to observe and identify for the first time transitions be¬ longing to the following of ro-vibrational bands: 3v2, 3v2 - v2, 2v2 - v2 bands of 32S16O2; 2v2 - v2 band of 34S16O2; v1 + v2, v2 + v3, v1 + v3, 2v1, 2v3 bands of 32S18O2; v1, v3, 2v1, v1 + v3, 2v3 bands of 32S16O18O. The inverse spectroscopic problems were solved for the studied states with the «rms»-deviation comparable to the experimental uncertainty of the spectral line position. As a result of the analysis about 38 000 ro-vibrational transitions belonging to 17 excited vibrational states were identified for the first time. The obtained highly accurate data on all sulfur dioxide isotopologues were used to correct the parameters of the IPF
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Nawrath, Pavel. "Forenzní analýza půdy metodami FTIR a NIR s multivariační analýzou." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-413556.
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This diploma thesis is about forensic multivariate soil analysis in the localities Ostrava and Třinec. A total of 52 samples were taken in the areas near metallurgical companies. These samples were measured for concentrations of chromium, manganese, copper, nickel, lead, mercury and zinc. Mercury concentration was analysed using AMA 254 device. The remaining metals were determined by flame atomic absorption spectrometry (F–AAS). Additionally, IR spectra were acquired by Fourier transform infrared spectroscopy (FTIR) using diffusion reflectance technique (DRIFT). In the end the results were used to create correlation models and statistical models of PCA (principal component analysis) methods with CA (correlation analysis).
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Wilcox, Kieaibi. "Using regression analyses for the determination of protein structure from FTIR spectra." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/using-regression-analyses-for-the-determination-of-protein-structure-from-ftir-spectra(1ad037eb-f237-4efe-867a-597239bd913e).html.
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One of the challenges in the structural biological community is processing the wealth of protein data being produced today; therefore, the use of computational tools has been incorporated to speed up and help understand the structures of proteins, hence the functions of proteins. In this thesis, protein structure investigations were made through the use of Multivariate Analysis (MVA), and Fourier Transformed Infrared (FTIR), a form of vibrational spectroscopy. FTIR has been shown to identify the chemical bonds in a protein in solution and it is rapid and easy to use; the spectra produced from FTIR are then analysed qualitatively and quantitatively by using MVA methods, and this produces non-redundant but important information from the FTIR spectra. High resolution techniques such as X-ray crystallography and NMR are not always applicable and Fourier Transform Infrared (FTIR) spectroscopy, a widely applicable analytical technique, has great potential to assist structure analysis for a wide range of proteins. FTIR spectral shape and band positions in the Amide I (which contains the most intense absorption region), Amide II, and Amide III regions, can be analysed computationally, using multivariate regression, to extract structural information. In this thesis Partial least squares (PLS), a form of MVA, was used to correlate a matrix of FTIR spectra and their known secondary structure motifs, in order to determine their structures (in terms of "helix", "sheet", “310-helix”, “turns” and "other" contents) for a selection of 84 non-redundant proteins. Analysis of the spectral wavelength range between 1480 and 1900 cm-1 (Amide I and Amide II regions) results in high accuracies of prediction, as high as R2 = 0.96 for α-helix, 0.95 for β-sheet, 0.92 for 310-helix, 0.94 for turns and 0.90 for other; their Root Mean Square Error for Calibration (RMSEC) values are between 0.01 to 0.05, and their Root Mean Square Error for Prediction (RMSEP) values are between 0.02 to 0.12. The Amide II region also gave results comparable to that of Amide I, especially for predictions of helix content. We also used Principal Component Analysis (PCA) to classify FTIR protein spectra into their natural groupings as proteins of mainly α-helical structure, or protein of mainly β-sheet structure or proteins of some mixed variations of α-helix and β-sheet. We have also been able to differentiate between parallel and anti-parallel β-sheet. The developed methods were applied to characterize the secondary structure conformational changes of an unfolding protein as a function of pH and also to determine the limit of Quantitation (LoQ).Our structural analyses compare highly favourably to those in the literature using machine learning techniques. Our work proves that FTIR spectra in combination with multivariate regression analysis like PCA and PLS, can accurately identify and quantify protein secondary structure. The developed models in this research are especially important in the pharmaceutical industry where the therapeutic effect of drugs strongly depends on the stability of the physical or chemical structure of their proteins targets; therefore, understanding the structure of proteins is very important in the biopharmaceutical world for drugs production and formulation. There is a new class of drugs that are proteins themselves used to treat infectious and autoimmune diseases. The use of spectroscopy and multivariate regression analysis in the medical industry to identify biomarkers in diseases has also brought new challenges to the bioinformatics field. These methods may be applicable in food science and academia in general, for the investigation and elucidation of protein structure.
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Rejaei, Ali Reza. "Correlation of FTIR spectra of protein gels to rheological measurements of gel strength." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23292.
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Globular proteins are important ingredients in many food formulations because of their nutritional value and their various functional properties such as gel formation. Proteins form gels by polymerization into a three-dimensional matrix. The rheological properties of the resulting viscoelastic solids can be obtained by Instron measurements. In the present work, gels were obtained by heating solutions of bovine serum albumin (BSA) in D$ sb2$O and egg albumin in H$ sb2$O under different conditions (i.e., pH, salt concentration, protein concentration, time of heating and temperature), and their gel strengths were measured by a compression test (Universal Testing Machine LRX). The Fourier transform infrared (FTIR) spectra of the same gel samples were recorded in order to investigate the changes in protein structure at the molecular level accompanying gel formation. Intermolecular $ beta$-sheet formation was found to increase as gel formation progresses at the expense of intramolecular $ beta$-sheet and $ alpha$-helix structures. For BSA, maximum gel strength was obtained around pH 7. The addition of salt had little effect on the gel strength while increase in protein concentration, time of heating and temperature increased the gel strength. The rate of denaturation of BSA and ovalbumin and of mixtures of these proteins in the ratios 9:1, 1:1, and 1:9 was also investigated by measuring the peak height of an aggregation band at 1618 cm$ sp{-1}$; some inhibitory effects of BSA on ovalbumin aggregation were observed. Correlations between the measured gel strengths and the amide I band profile in the FTIR spectra were examined using partial-least-squares (PLS) regression. These studies reveal that gel strengths of a particular protein gel could be adequately predicted from their infrared spectra without the need to carry out the rheological compression measurements.
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Morrell, Claire. "FTIR emission studies of chemical processes." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326026.
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Link, Jade Varaschim. "Estudo dos genótipos de café arábica utilizando FTIR e redes neurais artificiais." Universidade Tecnológica Federal do Paraná, 2013. http://repositorio.utfpr.edu.br/jspui/handle/1/504.
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CNPq; CAPES<br>As condições climáticas específicas de cada região de cultivo do café fornecem atributos especiais para a bebida e podem assim aumentar seu valor agregado. No entanto, é essencial provar a origem geográfica e genotípica do cultivar por meio de métodos confiáveis. Vários métodos matemáticos e estatísticos foram desenvolvidos na tentativa de reproduzir a capacidade humana de reconhecimento de padrões. As redes neurais artificiais (RNAs) são um conjunto de técnicas baseadas em princípios matemáticos e estatísticos, que vem atualmente ganhando espaço para realizar tarefas de regressão e reconhecimento de padrões. As RNAs são técnicas capazes de realizar o mapeamento de relações complexas e não lineares entre múltiplas variáveis de entrada e saída. Neste trabalho foram utilizados três tipos de rede neural artificial, o mapa auto-organizável (aprendizagem não-supervisionada), o perceptron de múltiplas camadas (aprendizagem supervisionada) e a rede de base radial (processo de aprendizagem híbrido), para o reconhecimento e classificação geográfica e genotípica de café arábica. Para esse fim a composição química e os espectros obtidos no equipamento de espectroscopia no infravermelho com transformada de Fourier (FTIR) foram analisados através do emprego de diferentes RNAs. No desenvolvimento das redes, foram aplicadas metodologias para: melhor generalização das redes (média de ensemble) e escolha dos parâmetros de rede (otimização simplex sequencial). O mapa auto-organizável apresentou foi capaz de reconhecer os genótipos de café e a sua origem geográfica, utilizando os dados do perfil químico das amostras. Após os resultados obtidos foi possível concluir que os perceptrons de múltiplas camadas otimizados foram capazes de classificar as amostras de café arábica geograficamente. Entretanto, para a classificação genotípica o desempenho não foi totalmente satisfatório. As redes de função de base radial otimizadas apresentaram resultados mais satisfatórios pois foram capazes de classificar as amostras de café arábica geograficamente e genotipicamente. Além dos melhores resultados obtidos para a classificação genotípica, as redes de função de base radial apresentam um número menor de parâmetros livres quando comparada com os perceptrons de múltiplas camadas, que apresentam um número muito elevado de pesos sinápticos, não proporcionando número suficiente de graus de liberdade para que a rede neural possa aprender de maneira confiável.<br>The climatic conditions of the coffee crop give special attributes to the beverage and could improve its value. However, it is essential to prove the geographical and genotype origin of the cultivar using reliable methods. Several mathematical methods have been developed in an attempt to reproduce the human capability of pattern recognition. The artificial neural networks (ANNs) are a set of techniques based on statistical principles, which is currently growing in the food science to perform tasks of regression and pattern recognition. ANNs are techniques that can represent complex and nonlinear input-output relationships. In this study three types of artificial neural network were used, namely the self-organizing maps (unsupervised learning), the multilayer perceptron (supervised learning) and the radial-basis function network (hybrid learning process), for the recognition and geographic and genotypic classification of arabic coffee. For this purpose, spectra obtained in the Fourier transform infrared (FTIR) were analyzed using different ANNs. Other techniques were also applied during neural network development: ensemble averaging to improve the network generalization and sequential simplex optimization to select parameters. It was concluded that the SOM were able to recognize the coffee genotypes and geographical origin using the chemical profile data. After the results it was concluded that the optimized multilayer perceptrons were able to classify the samples of arabica coffee geographically. However, for genotypic classification the performance was not satisfactory. The optimized radial-basis function networks showed more satisfactory results since these networks were able to classify the samples of arabica coffe geographically and genotypically. The radial-basis function networks presents the best results to genotypic classification and in addition a smaller number of free parameters compared with multilayer perceptrons, which has a high number of synaptic weights, thus a large degrees of freedom database is necessary to produce a network with generalization capability.
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Derenne, Allison. "FTIR spectra of cancer cells exposed to anticancer drugs reflect their cellular mode of action." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209494.
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There is an urgent need to develop reliable and cost-saving methods to select pre-clinically new drug candidates with original mechanism for cancer therapy. Previous results have shown that IR spectra of cancer cells exposed to various drugs provided a global signature of all the metabolic changes induced by the treatments. In this thesis, we attempted to develop a selection criterion – based on FTIR spectroscopy – for potential antitumor compounds according to their mechanism of action. <p>In chapter III, it was demonstrated that spectral variations in IR spectra of cancer cells induced by a treatment can be correlated to the mechanism of the drug. Human prostate cancer PC-3 cells were exposed to 7 well-described anticancer drugs belonging to 3 distinct classes. Each class is characterized by a unique mode of action. Drugs known to induce similar types of metabolic disturbances appear to cluster when spectrum shapes are analyzed. Chapter IV generalized the results obtained on PC-3 cells with six other cell lines. We showed that the spectral signatures of drug effects are mainly independent of the cell line. Chapter V indicated that, while the cell cycle phase influence IR spectra of cells, the drug spectral signature was dominated by global metabolic modifications and not much by the cell cycle perturbations due to this drug. <p>Chapter VI and VII focused on lipids. While the precise identification of particular molecules is particularly complex with IR spectroscopy, we attempted to extract more precise information and to assign spectral variations to specific changes in lipids. IR spectra of lipids contain very interesting details on their nature and structure. We achieved to build a tool which quantifies five major lipid classes in complex mixtures such as total lipid cell extracts. However, based on this tool, the treatments used do not induce any variation in the lipid cell composition (for five classes).<p>Finally, in chapter VIII, we applied the method developed previously on a new potential class of anticancer molecules: the polyphenols. A global method was particularly interesting as the development of therapy using these compounds is hampered by the complexity of the multiple anticarcinogenic mechanisms of these molecules. We have noticed the similarities and discrepancies among 3 very close synthetic molecules and the observations were coherent with previous biological data. We also compared them with 3 natural molecules already in clinical phase for treatment of various cancers.<p>In conclusion, we developed an objective classifier for potential anticancer drugs based on their global effects on cancer cells. Applied to a larger scale, this method could constitute a first step in the screening method to select drugs with original mode of action.<p>There is an urgent need to develop reliable and cost-saving methods to select pre-clinically new drug candidates with original mechanism for cancer therapy. Previous results have shown that IR spectra of cancer cells exposed to various drugs provided a global signature of all the metabolic changes induced by the treatments. In this thesis, we attempted to develop a selection criterion – based on FTIR spectroscopy – for potential antitumor compounds according to their mechanism of action. <p>In chapter III, it was demonstrated that spectral variations in IR spectra of cancer cells induced by a treatment can be correlated to the mechanism of the drug. Human prostate cancer PC-3 cells were exposed to 7 well-described anticancer drugs belonging to 3 distinct classes. Each class is characterized by a unique mode of action. Drugs known to induce similar types of metabolic disturbances appear to cluster when spectrum shapes are analyzed. Chapter IV generalized the results obtained on PC-3 cells with six other cell lines. We showed that the spectral signatures of drug effects are mainly independent of the cell line. Chapter V indicated that, while the cell cycle phase influence IR spectra of cells, the drug spectral signature was dominated by global metabolic modifications and not much by the cell cycle perturbations due to this drug. <p>Chapter VI and VII focused on lipids. While the precise identification of particular molecules is particularly complex with IR spectroscopy, we attempted to extract more precise information and to assign spectral variations to specific changes in lipids. IR spectra of lipids contain very interesting details on their nature and structure. We achieved to build a tool which quantifies five major lipid classes in complex mixtures such as total lipid cell extracts. However, based on this tool, the treatments used do not induce any variation in the lipid cell composition (for five classes).<p>Finally, in chapter VIII, we applied the method developed previously on a new potential class of anticancer molecules: the polyphenols. A global method was particularly interesting as the development of therapy using these compounds is hampered by the complexity of the multiple anticarcinogenic mechanisms of these molecules. We have noticed the similarities and discrepancies among 3 very close synthetic molecules and the observations were coherent with previous biological data. We also compared them with 3 natural molecules already in clinical phase for treatment of various cancers.<p>In conclusion, we developed an objective classifier for potential anticancer drugs based on their global effects on cancer cells. Applied to a larger scale, this method could constitute a first step in the screening method to select drugs with original mode of action.<p><p>Afin d’améliorer les thérapies contre le cancer, il devient actuellement cruciale de développer une méthode pour améliorer la sélection préclinique de nouvelles molécules, potentiellement anticancéreuses. Des publications précédentes ont mis en évidence que les spectres infrarouges de cellules cancéreuses exposées à différents agents thérapeutiques fournissent une empreinte globale de l’ensemble des changements métaboliques induit par ce médicament. Dans cette thèse, nous proposons d’utiliser la spectroscopie infrarouge pour mettre au point un critère de sélection basé sur le mode d’action des agents anticancéreux. Plusieurs aspects de la technique ont été investigués. Nous avons d’abord démontré la possibilité d’utiliser les spectres infrarouges de cellules cancéreuses de prostate PC-3 traitées avec 7 drogues pour classer ces molécules selon leur mode d’action. Nous avons ensuite reproduit les résultats obtenus sur PC-3 avec 6 autres lignées cellulaires et montré que la signature spectrale obtenue était largement indépendante de la lignée. Par la suite, nous avons étudié si l’effet sur le cycle cellulaire induit par de nombreuses molécules anticancéreuses, pouvait expliquer certains changements spectraux observés suite au traitement. Nous avons pu montrer que la majorité des variations spectrales n’étaient pas liées à une perturbation du cycle cellulaire. Nous nous sommes ensuite concentrés sur une classe de molécules en particulier: les lipides. Après avoir mis en évidence l’ensemble des informations contenues dans un spectre infrarouge de lipides, nous avons mis au point un modèle permettant de quantifier 5 classes de lipides dans des mélanges complexes tels que des extraits lipidiques provenant de cellules. Néanmoins, aucune variation du contenu en ces 5 classes de lipides n’a été observée pour les traitements utilisés dans cette étude. Enfin, nous avons appliqué la méthode mise au point dans cette thèse à une classe de molécules prometteuses :les polyphénols. Une approche globale s’avère particulièrement intéressante pour ces composés étant donné qu’ils présentent des mécanismes anticancéreux multiples et complexes. Nous avons comparé 3 molécules naturelles en phase clinique pour le traitement de certains cancers et 3 molécules synthétiques présentant une structure très proche. Par notre méthode, nous avons mis en évidence certaines similarités et différences de ces 6 molécules en termes d’effets globaux sur les cellules. En conclusions, nous avons développé un outil objectif de classification pour les molécules anticancéreuses potentielles, basée sur le mécanisme global des composés. Appliquée à plus large échelle, cette méthode pourrait constituer une première étape permettant de sélectionner les molécules avec un mode d’action original.<br>Doctorat en Sciences agronomiques et ingénierie biologique<br>info:eu-repo/semantics/nonPublished
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Dohe, Susanne [Verfasser], and M. [Akademischer Betreuer] Olzmann. "Measurements of atmospheric CO2 columns using ground-based FTIR spectra / Susanne Dohe. Betreuer: M. Olzmann." Karlsruhe : KIT-Bibliothek, 2013. http://d-nb.info/1047383500/34.
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Arshad, Khubaib, and Muhammad Mujahid. "Biodegradation of Textile Materials." Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20862.
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In this research work different textile materials were buried in soil and their biodegrading pattern will be studied after different specific period of times.<br>Program: Master Programme in Textile Technology
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Ibrahim, Amr, and University of Lethbridge Faculty of Arts and Science. "Spectroscopic study of channel spectra phenomena in the synchrotron-based FTIR spectrometer at the Canadian Light Source." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Physics and Astronomy, c2010, 2010. http://hdl.handle.net/10133/2638.
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Recently, the high radiance of synchrotron sources was used to enhance FTIR
spectrometer performance. However, excessive channel spectra when synchrotron
sources are used degrade the quality of retrieved spectral parameters. In the
research reported in this thesis, seven different techniques for handling channel
spectra were investigated. These techniques were used to reduce channel spectra
for a test group of seven samples of CO2 mixed with air recorded using the
synchrotron source at the Canadian Light Source. The increases in signal to noise
ratio (SNR) of spectra handled with each technique were calculated. SNR results
showed that transmission spectra, produced using synthetic background spectra
with simulated channel spectra, achieved the highest SNR improvement. However,
when the spectra groups were fitted using nonlinear least square fit algorithm, the
technique using channel spectra fitting produced the smallest fitting residual.
Moreover, the retrieved intensities and air broadening coefficients of 21 spectral
lines showed that the spectral fitting technique produced the most accurate values
as compared to the HITRAN 2008 database. Although the spectral fitting technique
was accurate in retrieving spectral line parameters, applying the technique at wider
spectral ranges was less accurate.
A modification to the channel spectra fitting technique by performing
iterations of channel fitting was introduced to process wider spectral ranges.
Carbon dioxide laser band I centred at 961 wavenumber was analyzed using 24
spectra recorded under different experimental conditions. The intensity and air-and self-broadening coefficients were retrieved for 48 spectral lines with average
deviations from HITRAN database values of 2.11%, 1.25% and 4.14%, respectively,
using the Voigt profile. These average deviations lie within the uncertainty limits
listed by the database. The deviation between our results and other results reported
in the literature were also examined and it is found to be also within the range of
HITRAN uncertainties. The effect of errors in fitting channel spectra parameters was
examined and found to be mitigated by the inclusion of channel-free spectra in the
multispectral fit.<br>xiv, 134 leaves : ill. ; 29 cm
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PEREIRA, THIAGO M. "Análise das diferenças bioquímicas nos tecidos e lesões tireoidianas por imageamento espectral no infravermelho (FTIR)." reponame:Repositório Institucional do IPEN, 2013. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10567.
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Made available in DSpace on 2014-10-09T12:42:03Z (GMT). No. of bitstreams: 0<br>Made available in DSpace on 2014-10-09T14:04:44Z (GMT). No. of bitstreams: 0<br>Tese (Doutoramento)<br>IPEN/T<br>Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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BENETTI, CAROLINA. "Estudo in-vitro dos efeitos do laser de Er,Cr:YSGG em tecido osseo por espectroscopia ATR-FTIR." reponame:Repositório Institucional do IPEN, 2010. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9509.
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Made available in DSpace on 2014-10-09T12:27:27Z (GMT). No. of bitstreams: 0<br>Made available in DSpace on 2014-10-09T14:06:47Z (GMT). No. of bitstreams: 0<br>Dissertacao (Mestrado)<br>IPEN/D<br>Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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BENETTI, CAROLINA. "Estudo da reparação óssea por espectroscopia ATR-FTIR após remoção de fragmento da região mandibular com laser de Er, Cr:YSGG ou broca multilaminada." reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11807.
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No. of bitstreams: 0<br>Made available in DSpace on 2014-11-10T12:16:48Z (GMT). No. of bitstreams: 0<br>Tese (Doutorado em Tecnologia Nuclear)<br>IPEN/T<br>Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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VELOSO, MARCELO N. "Avaliação in vitro dos efeitos da radiação ionizante em tecido ósseo bovino por espectroscopia ATR-FTIR e análise dinâmico-mecânica." reponame:Repositório Institucional do IPEN, 2013. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10573.
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Toledo, Alvarado Hugo Oswaldo. "Relationships between fertility of cows and their milk yield, composition and infrared spectra." Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3426318.
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Milk production has a strong effect on fertility and at the same time reproduction affects the milk composition. In the last decade, special interest has arisen in studying milk composition and its relation with health, efficiency, and fertility. Therefore the principal objective of this thesis was to assess the relationships between the fertility of dairy cows and their milk yield, composition, and infrared spectra.
Data used were collected by the Breeders Federation of Alto Adige/Südtirol from the northeastern Italian province of Bolzano/Bozen. The milk’s data comprises production, composition and physical properties. For fertility, all the insemination dates were available as well as the calving date. The milk samples collected were analyzed using a MilkoScanTM FT+ 6000 (Foss Electric, Hillerød, Denmark), the spectrum covered 1,060 wavenumbers (wn) from 5,010 to 925 cm-1. Four breeds were studied: the specialized dairy breeds Holstein and Brown Swiss and the double purpose breeds Simmental and Alpine Grey.
The effects of breed and its interaction with milk productivity at the herd level (Herd-L) and at cow-within-herd level (Cow-L) on fertility traits in dairy cattle were studied in the second chapter. A mixed model was fitted to establish milk production levels of the various herds and individual cows according to milk yield. The interval calving-first service (iCF), interval first service-conception (iFC) and days open (DO) traits were analyzed using a Cox’s proportional hazards model. The non-return rate at 56d after first service (NRR), pregnancy rate at first service (PRF) and the number of inseminations (INS) traits were analyzed using a logistic regression. It was observed a strong interaction between breed and productivity class at both Herd-L and Cow-L on all traits. The dual-purpose Simmental and Alpine Grey breeds had better fertility than the specialized Holstein and Brown Swiss dairy cows, also at the same daily milk yield, and the effects of herd and cow productivity differed from each other and differed among breeds. In conclusion, greater herd productivity can result in higher fertility in cows, while a higher milk yield of individual cows within a herd results in lower fertility. These effects at both Herd-L and Cow-L are curvilinear and stronger in the dual-purpose breeds, being more evident from the low to the intermediate levels than moving from the intermediate to the high productivity classes.
The relationships between the estrous cycle phases in dairy cattle to milk composition, milk physical indicators and milk fatty acids were assessed in the third chapter. The test days around the first insemination after calving in the range from -10 to +10 days were selected and classified in 5 phases: Diestrus high-progesterone (Diestrus-HP) from -10 to -4 d; Proestrus from -3 to -1 d; Estrus day 0 (insemination day); Metestrus from 1 to 2 d; and Diestrus increasing-progesterone (Diestrus-IP) from 3 to 10 d. A mixed model was fitted to analyze the milk components and the milk physical indicator properties, including the effect of the estrous phases and we estimated the contrasts among them. The milk composition showed high variability among the estrous phases, affecting principally the fat, protein and lactose. The fatty acid profile and the physical indicators were also highly affected indicating important differences occasioned by the hormonal and behavioral changes of cows in estrus.
The predictive abilities of fat, protein, lactose, casein, and FTIR spectral data to predict cow’s pregnancy status (PS) were assessed in the fourth chapter. We used generalized linear models to predict PS using fat, protein, lactose, casein and single FTIR spectral bands. We also fitted a Bayesian variable selection model to predict PS using the complete FTIR spectrum. Prediction accuracy was evaluated using a 10 fold cross-validation study and calculating the area under a receiver operating characteristic curve (CV-AUC) based on phenotypic predictions and observations. Overall, the most prediction accuracies were obtained for a model that included the complete FTIR spectral data. Alpine Grey cows had the highest CV-AUC (0.645), while Brown Swiss and Simmental had similar results (0.630 and 0.628 respectively) and Holsteins had the lowest value for FTIR Spectra (0.607). For the single wavelength analyses, important peaks were detected at: from wn 2,973 to wn 2,872 cm-1 where Fat-B is usually filtered; wn 1,773 cm-1 where Fat-A is filtered; wn 1,546 cm-1 where protein is filtered; wn 1468 cm-1 associated with urea and fat; wn 1,399 cm-1 and wn 1,245 cm-1 associated with acetone; from wn 1,025 cm-1 to wn 1,013 x cm-1 where lactose is filtered. This research provides new insights to alternative strategies for pregnancy status screening on dairy cattle.<br>La produzione di latte ha un forte effetto sulla fertilità delle bovine e allo stesso tempo la riproduzione influisce sulla composizione del latte. Negli ultimi decenni, si è sviluppato un particolare interesse riguardo lo studio della composizione del latte e del suo rapporto con la salute, l'efficienza e la fertilità. Pertanto l'obiettivo principale di questa tesi è stato quello di valutare i rapporti tra la fertilità delle bovine da latte e la loro produzione di latte, la composizione e gli spettri a infrarossi del latte prodotto.
I dati utilizzati sono stati raccolti dalla Federazione Allevatori dell’ Alto Adige / Südtirol di Bolzano / Bozen in Italia. I dati relativi al latte comprendono la produzione, la composizione e le proprietà fisiche. Per la fertilità, sono state considerate tutte le date di fecondazione e il giorno di parto. I campioni di latte raccolti sono stati analizzati utilizzando un MilkoScanTM FT + 6000 (Foss Electric, Hillerød, Danimarca), e lo spettro ricopriva 1,060 lunghezze d’onda, da 5,010 a 925 cm-1. Sono state utilizzate quattro razze: le razze specializzate Frisona e Bruna, e le razze a duplice attitudine Pezzata Rossa e Grigio Alpina.
Nel secondo capitolo sono stati studiati gli effetti della razza e la sua interazione con la produzione di latte a livello di allevamento (Herd-L) e a livello individuale (di vacca entro allevamento) (Cow-L) sui caratteri di fertilità nelle bovine da latte. Per stabilire i livelli di produttività delle varie aziende e delle singole vacche, in base alla produzione di latte, è stato utilizzato un modello misto. L’intervallo dal parto alla prima inseminazione (iCF), l'intervallo dalla prima inseminazione al concepimento (iFC) e l’intervallo parto concepimento (DO) sono stati analizzati utilizzando un modello di rischio proporzionale di Cox. Il tasso di non ritorno a 56 giorni dopo il primo servizio (NRR), il tasso di gravidanza al primo servizio (PRF) e il numero di inseminazioni (INS) sono stati analizzati utilizzando una regressione logistica. Per tutti i caratteri è stata osservata una forte interazione tra la razza e la classe di produttività, sia a livello di allevamento che a livello individuale. Le razze a duplice attitudine Pezzata Rossa e Grigio Alpina hanno una migliore fertilità rispetto alle vacche da latte specializzate di razza Frisona e Bruna, anche a parità di produzione, e gli effetti della produttività aziendale e individuale differivano tra loro e tra le razze. In conclusione, una maggiore produttività dell’ azienda può determinare una maggiore fertilità nelle vacche, mentre una maggiore produzione di latte delle singole vacche all'interno di una azienda può risultare in una minore fertilità. Questi effetti, sia livello di allevamento che a livello individuale, hanno un andamento curvilineo e sono più forti nelle razze a duplice attitudine, essendo più evidenti passando da una produttività bassa a una intermedia, piuttosto che passando dal livello intermedio alle classi di produttività elevata.
Nel terzo capitolo sono state valutate le relazioni tra le fasi dell’estro nei bovini da latte e la composizione, gli indicatori fisici e gli acidi grassi del latte. I giorni di campionamento attorno alla prima inseminazione dopo il parto, nell'intervallo da -10 a +10 giorni, sono stati selezionati e classificati in 5 fasi: diestro-alto progesterone (Diestrus-HP) da -10 a -4 giorni; proestro da -3 a -1 giorni; giorno di estro 0 (giorno di inseminazione); metestro da 1 a 2 giorni; e diestro-progesterone in aumento (Diestrus-IP) da 3 a 10 giorni. Per analizzare i componenti del latte e gli indicatori fisici delle proprietà del latte è stato usato un modello misto, includendo l'effetto dell’a fase estrale, e abbiamo stimato i contrasti tra di essi. La composizione del latte ha mostrato un'elevata variabilità tra le fasi diverse dell’estro, e i caratteri maggiormente influenzati sono stati il grasso, la proteina e il lattosio. Anche il profilo acidico e gli indicatori fisici sono stati notevolmente influenzati, indicando importanti differenze causate dalle modifiche ormonali e comportamentali delle bovine in estro.
Nel quarto capitolo è stata valutata l’abilità di predizione dello stato di gravidanza delle vacche (PS) utilizzando grasso, proteina, caseina, lattosio e gli spettri FTIR . Per predire lo stato di gravidanza sono stati utilizzati modelli lineari generalizzati utilizzando grasso, proteina, lattosio, caseina e le singole lunghezze d’onda FTIR. È stato inoltre fittato un modello Bayesiano di selezione di variabile per predire lo stato di gravidanza utilizzando lo spettro FTIR completo . L’accuratezza di predizione è stata valutata utilizzando uno studio di validazione incrociata ripetuto 10 volte e calcolando l'area sotto a la curva del -receiver operating characteristic- (CV-AUC) basata sulle predizioni fenotipiche e sulle osservazioni. Nel complesso, le migliori accuratezze di predizione sono state ottenute per un modello che includeva i dati spettrali FTIR completi. Le vacche Grigio alpine hanno ottenuto il più alto CV-AUC (0.645), Brune e Pezzate Rosse hanno ottenuto risultati simili (0.630 e 0.628 rispettivamente), mentre le Frisone hanno ottenuto il valore più basso per gli spettri FTIR (0.607) completi. Per le singole analisi di lunghezza d'onda, picchi importanti sono stati rilevati: da wn 2,973 a wn 2,882 cm-1 corrispondente al filtro Fat-B delle analisi con monocromatore; wn 1,773 cm-1 dove è posizionato il filtro grasso-A; wn 1,546 cm-1 dove è posizionato il filtro della proteina; wn 1,468 cm-1 che è associato a urea e grasso; wn 1,399 cm-1 e wn 1,245 cm-1 associati con l’acetone; da wn 1,025 cm-1 fino a 1,013 x cm-1 dove è posizionato il filtro del lattosio. Questa ricerca fornisce nuove conoscenze riguardo a strategie alternative per lo screening dello stato di gravidanza dei bovini da latte.
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Noreen, Razia. "FTIR imaging of collagens in gliomas." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14316/document.
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Le gliome est le type le plus agressif et mortel de tumeur cérébrale. Ces tumeurs se caractérisent par la présence conjointe de phénotypes solides (de bas grade, moins invasif, hautement vascularisé) et diffus (haut grade, très envahissant et diffus) des glioblastomes multiformes. Les collagènes sont des composants majeurs de la MEC des cellules tumorales des gliomes, et sont également présents dans la membrane basale des vaisseaux sanguins, mais avec une composition différente entre vasculatures saine et tumorale. L'abondance et la typologie des collagènes dans la MEC des cellules tumorales et la vasculature représentent donc un marqueur potentiel de diagnostic pour la gradation des tumeurs gliales. Nous avons développé la spectro-imagerie infrarouge à transformée de Fourier pour déterminer les modifications morphologiques et moléculaires apparaissant dans les formes solides et diffuses de gliomes, ainsi que dans les vasculatures saine et tumorale. Nous avons d'abord mis en évidence les vasculatures saine et tumorale en utilisant des nanoparticules injectées dans le système sanguin. Ensuite, nous avons appliqué des méthodes de reconstruction spectrale pour distinguer les tissus sains vs. ceux des formes solide et diffuse de tumeurs sur la base de leurs contenus en collagène de la MEC. Enfin, nous avons déterminé les changements de types du collagène au cours de la progression tumorale, validant ainsi la notion que l’analyse de ces contenus est potentiellement un marqueur diagnostic pour la gradation des gliomes<br>The glioma is the most aggressive and lethal type of brain tumor. Such tumor is characterized both by solid (low grade, less invasive, highly vascularized) and diffuse (high grade, very invasive and diffuse) phenotypes in high-grades. Collagens are major components of ECM in glioma tumor cells, and are also present in basement membrane of blood vessels in vasculature, but with different composition between healthy and tumor capillaries. The abundance and typology of collagens in tumor cell ECM and vasculature is thus a potential diagnostic marker for grading glioma tumors. We developed Fourier transform infrared (FTIR) spectro-imaging as a functional technique to determine the morphological and molecular changes occurring in solid and diffuse form of tumor tissues as well as in healthy and tumor vasculatures. We first highlighted healthy and tumor vasculatures using nanoparticles injected in blood system. Then, we applied curve-fitting methods to distinguish between healthy tissue vs. solid and diffuse tumor tissues on the basis of the collagen contents found in ECM. Finally, we determined collagen typology changes during tumor progression, thus validating that collagen contents analysis is potentially a diagnostic marker for glioma grading
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Inberg, R. Brandon. "Enhanced step mode FTIR position control." Thesis, Montana State University, 2005. http://etd.lib.montana.edu/etd/2005/inberg/InbergR1205.pdf.
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Sonnendecker, Paul Walter. "Quantitative analysis of time-resolved FTIR specta : steps towards full automation." Diss., University of Pretoria, 2015. http://hdl.handle.net/2263/56109.
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Inline, time-resolved FTIR spectra are commonly recorded after completion of the experiments. The abilities and versatility of FTIR spectroscopy can, however, also be utilised in the in situ quantification of absorbing mixtures. Recent developments, in the laboratory where this investigation was conducted, demands the inline quantification of PTFE pyrolysis products for process control purposes. This investigation is primarily focused on the development of a procedure and software capable of processing, fitting and quantifying real-time, time-resolved spectra. Processing methods were evaluated with respect or improvement in SNR, smoothing and baseline tracking of infrared spectra. Execution speed was also considered due the need for real-time analysis. The asymmetric least squares method proved to be the optimal choice with respect to the mentioned criteria. An asymmetric lineshape fitting function together with a Levenberg-Marquardt nonlinear solving function was introduced to represent pure component spectra mathematically. A method for quantitative analysis by means of solving a linear set of equations was developed. The software was implemented on the batch pyrolysis of PTFE pyrolysis as test case. Experiments were conducted to obtain sufficient samples of the components such that FTIR spectra could be captured. Infrared spectra of the perfluorobutenes were experimentally determined. These spectra could not be found in the available literature and are deemed to be novel. The ability of the software to perform real-time quantification of the PTFE pyrolysis stream was demonstrated over a range of experimental conditions spanning the temperature range 650 ºC to 850 ºC, and pressures from <1kPa to 70 kPa.<br>Dissertation (MEng)--University of Pretoria, 2015.<br>tm2016<br>Chemical Engineering<br>MEng<br>Unrestricted
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Hung, Wing Wa. "FTIR and XPS of congruent and stoichiometric LiNbO3." HKBU Institutional Repository, 2003. http://repository.hkbu.edu.hk/etd_ra/442.
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Chatterton, Logan. "Spectral analysis of petroleum reservoir rock using fourier transform infrared (FTIR) spectroscopy." Thesis, Oklahoma State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10140532.
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<p> Compositional analysis of reservoir rock is a vital aspect of oil exploration and production activities. In a broad sense, knowing the mineral composition of a reservoir can help with characterization and interpretation of depositional environments. On a smaller scale, identifying mineralogy helps calibrate well logs, identify formations, design drilling and completion programs, and screen for intervals with potential problem minerals, such as swelling clays. The petroleum industry utilizes two main methods to find compositional mineralogy, x-ray diffraction (XRD) and thin section analysis. Both methods are time consuming, expensive, and destructive. An alternative method for compositional analysis that includes quantitative mineralogy is a valuable prospect, especially if it had the potential to characterize the total organic content (TOC). </p><p> The remote sensing community has been using infrared spectroscopy to analyze mineralogy for years. Within the last ten years, the advancement of infrared spectrometers and processing programs have allowed infrared spectra to be taken and analyzed faster and easier than before. The objective of this study is to apply techniques used in remote sensing for quantitatively finding mineralogy to the petroleum industry. While developing a new methodology to compositionally analyze reservoir rock, a database of infrared spectra of relevant minerals has been compiled. This database was used to unmix spectra using a constrained linear least-squares algorithm that is used in the remote sensing community. A core has been scanned using a hand-held infrared spectrometer. Results of the best method show RMS error from mineral abundance to be under five percent.</p>
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Ellis, Daniel Jared. "Temperature Measurement Using Infrared Spectral Band Emissions From H2O." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5488.
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Currently there is no known method for accurately measuring the temperature of the gas phase of combustion products within a solid fuel flame. The industry standard is a suction pyrometer and thermocouple which is intrusive, both spatially and temporally averaging, and difficult to use. In this work a new method utilizing the spectral emission from water vapor is investigated through modeling and experimental measurements. This method was demonstrated along a 0.75m line of sight, averaged over 1 minute in the products of a natural gas flame but has the potential to produce a spatial resolution on the order of 5 cm and a temporal resolution of less than 1 millisecond. The method employs the collection of infrared emission from water vapor over discrete wavelength bands and then uses the ratio of those emissions to infer temperature. A 12.5 mm lens has been positioned within a water cooled probe to focus flame product gas emission into an optical fiber where the light is transmitted to a Fourier Transform Infrared Spectrometer (FTIR). The same optical setup was also used to collect light from a black body cavity at a known temperature in order to calibrate the spectral sensitivity of the optical system and FTIR detector. Experiments were conducted in the product gas of a 150 kWth methane flame comparing the optical emission results to a suction pyrometer with type K thermocouple. The optical measurement produced gas temperatures approximately 1 - 4% higher than the suction pyrometer. Broadband background emission was also seen by the optical measurement and was removed assuming grey body radiation. This background emission can be used to determine particle emission temperature and intensity. Additional work will be needed to demonstrate the method under conditions with significant particle emission. Additional work is also needed to demonstrate the work over a smaller path length and shorter time scale.
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Egbert, Scott Cutler. "Pressurized Combustion Product Temperature Measurement Using Integrated Spectral Band Ratios." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7535.
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With increasing global power demands, there is a growing need for the clean and efficient use of fossil fuel resources. Gas turbine engines are a commonly used means for generating power; from the propulsion of aircraft to electricity on municipal grids. Measuring the temperature within a turbine combustor or at a turbine inlet could provide numerous advantages related to engine control, durability, efficiency, and emissions and yet this relatively straightforward task has eluded turbine engine manufacturers, primarily because of the high temperatures and pressures, harsh environment, and limited access. Optical emissions measurements are of particular interest for this task as they only require one optical access point and can be accomplished using thin optical fibers that can be fit within existing turbine geometries.This work extends an optical emission method known as the integrated spectral band ratio (ISBR) method beyond previously obtained temperature measurements on atmospheric combustion products to temperature measurements in a pressurized turbine combustor. The ISBR correlates modeled integrated spectral band ratios of spectral water emission to gas temperature, comparable to two-color pyrometry. When the integrated spectral bands are measured, the temperature can be inferred from this correlation. This technique has previously been successfully applied at atmospheric conditions over pathlengths as short at 25 cm but in this case has been applied at pressures of 0.7 and 1.2 MPa and a pathlength of 15 cm.Optical measurements were taken in a pressurized combustion test rig at Solar Turbines Inc. in San Diego California. Two temperature sweeps at high load and low load (pressures of 1.2 and 0.7 MPa, respectively) were measured. The average ISBR optical temperature measurements were approximately 200 K higher than the downstream thermocouple measurements. Thermocouple radiative losses were predicted to yield a bias of -175 K. The slope of a change in optical temperature to change in thermocouple temperature was 1.03 over the 87 K variation seen. Repeatability of the optical measurement at a given operating condition was on the order of ± 15 K and the absolute uncertainty of a single measurement was estimated to be ± 70 K over a temperature range of 1350 to 1500 K. The spectra, measured with a Fourier Transform Infrared Spectrometer (FTIR), was in very good agreement with spectral emission models produced using a derivative of the HITEMP database. All of the measured peak locations matched the model, and the measured data matched changes in spectral wings with changing pressure. A linear correlation was also found between raw optical signal and thermocouple measurements.
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Kiel, Matthäus [Verfasser], and J. [Akademischer Betreuer] Orphal. "Trace gas measurements from different spectral regions using FTIR spectroscopy / Matthäus Kiel. Betreuer: J. Orphal." Karlsruhe : KIT-Bibliothek, 2016. http://d-nb.info/1108451950/34.
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Naqvi, Shabbar. "Modelling FTIR spectral sata with Type-I and Type-II fuzzy sets for breast cancer grading." Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/14321/.
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Breast cancer is one of the most frequently occurring cancers amongst women throughout the world. After the diagnosis of the disease, monitoring its progression is important in predicting the chances of long term survival of patients. The Nottingham Prognostic Index (NPI) is one of the most common indices used to categorise the patients into different groups depending upon the severity of the disease. One of the key factors of this index is cancer grade which is determined by pathologists who examine cell samples under a microscope. This manual method has a higher chance of false classification and may lead to incorrect treatment of patients. There is a need to develop automated methods that employ advanced computational methods to help pathologists in making a decision regarding the classification of breast cancer grade. Fourier transform infra-red spectroscopy (FTIR) is one of the relatively new techniques that has been used for diagnosis of various cancer types with advanced computational methods in the literature. In this thesis we examine the use of advanced fuzzy methods with the FTIR spectral data sets to develop a model prototype that can help clinicians with breast cancer grading. Initial work is focussed on using the commonly used clustering algorithms k-means and fuzzy c-means with principal component analysis on different cancer spectral data sets to explore the complexities within them. After that, a novel model based on Type-II fuzzy logic is developed for use on a complex breast cancer FTIR spectral data set that can help clinicians classify breast cancer grades. The data set used for the purpose consists of multiple cases of each grade. We consider two types of uncertainty, one within the spectra of a single case of a grade (intra -case) and other when comparing it with other cases of same grade (inter-case). Features have been extracted in terms of interval data from various peaks and troughs. The interval data from the features has been used to create Type-I fuzzy sets for each case. After that the Type-I fuzzy sets are combined to create zSlices based General Type-II fuzzy sets for each feature for each grade. The created benchmark fuzzy sets are then used as prototypes for classification of unseen spectral data. Type-I fuzzy sets are created for unseen spectral data and then compared against the benchmark prototype Type-II fuzzy sets for each grade using a similarity measure. The best match based on the calculated similarity scores is assigned as the resultant grade. The novel model is tested on an independent spectral data set of oral cancer patients. Results indicate that the model was able to successfully construct prototype fuzzy sets for the data set, and provide in-depth information regarding the complexities of the data set as well as helping in classification of the data.
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Wehbe, Katia. "Usage of FTIR spectro-imaging for the development of a molecular anatomo-pathology of cerebral tumors." Thesis, Bordeaux 1, 2008. http://www.theses.fr/2008BOR13677/document.
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Les gliomes sont des tumeurs agressives de mauvais pronostic, très angiogéniques et infiltrantes ce qui rend leur exérèse particulièrement difficile. Vu les limites des techniques actuelles d’imagerie, nous avons proposé la spectro-imagerie Infrarouge à Transformée de Fourier (IRTF), d’une résolution spatiale de 6 µm, pour apporter une information moléculaire à l’examen histologique actuel des gliomes. Nos travaux ont été fondés sur la recherche de paramètres moléculaires des vaisseaux sanguins, notamment sur la base des contenus de leur membrane basale. Celle-ci subit des altérations dûes au stress angiogénique tumoral. Nous avons mis en évidence des altérations de la structure secondaire des protéines (tels les collagènes) des vaisseaux sanguins au cours de la croissance de la tumeur. Nous avons aussi évalué les modifications des chaines d’acides gras des phospholipides membranaires, qui révélent un degré d’insaturation plus important pour les vaisseaux tumoraux. Ensuite, sur un modèle de gliome murin, nous avons établi une méthode efficace de classification des capillaires sanguins sur la base d’absorptions de leurs contenus glucidiques et lipidiques, permettant de discriminer totalement les capillaires sains et tumoraux. La combinaison de ces paramètres a été mise à profit pour assurer une histopathologie moléculaire des gliomes humains. Nos résultats ont démontré qu’il est possible de différencier entre la vasculature saine et tumorale sur ces gliomes humains, ce qui permet une bonne délimitation des zones tissulaires correspondantes. Cette technique pourrait devenir un outil analytique fiable, rapide d’une durée compatible avec la chirurgie et donc très utile pour les neurochirurgiens<br>Malignant gliomas are very aggressive tumors with poor prognosis, highly angiogenic and invasive into the surrounding brain parenchyma, making their resection very difficult. Regarding the limits of current imaging techniques, we have proposed Fourier Transform Infrared (FTIR) spectro-imaging, with a spatial resolution of 6 µm, to provide molecular information for the histological examination of gliomas. Our work was based on the research of molecular parameters of blood vessels, notably on the basis of the contents of their basement membrane, which undergoes changes due to tumor angiogenic stress. We have identified alterations of the secondary structure of proteins (such as collagen) in blood vessels during tumor growth. We have also assessed the changes in fatty acyl chains of membrane phospholipids, which revealed a higher unsaturation level in tumor vessels. Then, on a murine glioma model, we have established an efficient method of blood vessels classification based on their carbohydrates and fats contents, allowing the differentiation between healthy and tumor blood vessels. The combination of these parameters was used to provide a molecular histopathology for the study of human gliomas. Our results have demonstrated the feasibility of differentiating between healthy and tumor vasculature in these human gliomas, which help delimitating areas of corresponding tissue. This technique could become a reliable and fast analytical tool, with duration compatible with the surgery and thus very useful for neurosurgeons
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Mondaca, Fernandez Iram. "Spectroscopy Techniques for quantification of Microorganisms in Environmental Samples." Diss., The University of Arizona, 2005. http://hdl.handle.net/10150/194103.
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Microbiological monitoring of water is of primary importance for preservation of human health, particularly in an arid zone like the U.S. southwest. In this work, infrared spectroscopic methods were developed to identify and quantify microorganisms present in water and water-related environmental samples. Focus of the work was primarily on evaluating the impact of various sterilization methods on microorganism physiology as gauged by the non-invasive approach of infrared spectroscopy. This work demonstrates that FTIR techniques can be used to identify changes in the physiology of microorganisms and that for heat treatment, a correlation between spectral changes and the viability of microorganisms can be made.
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de, Ghellinck d'Elseghem Vaernewijck Xavier. "Instrumental contribution to FTIR spectroscopy using a femto-OPO laser source and cavity enhanced absorption." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209629.
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L'expérience nommée femto-FT-CEAS a été mise en place durant ce travail. Elle<p>combine une source d'absorption laser femto-opo, une cavité optique haute finesse<p>et un interféromètre à transformée de Fourier. Ce montage instrumental a permis<p>d'enregistrer des spectres sur un domaine de 100 cm−1 avec un coefficient d'absorption<p>minimal détectable de 5 10−10cm−1 pour des paramètres de résolution spectrale de<p>2 10−2cm−1 et un temps d'enregistrement d'une heure. Le coefficient d'absorption<p>equivalent par moyenne quadratique par élément spectral correspondant est de 1.2<p>10−12cm−1 Hz−1/2. Un chemin optique équivalent de 13 km a été obtenu dans une<p>cellule de 77 cm de long. La gamme spectrale accessible est de 6000 − 6700 cm−1 et<p>7800 − 8300 cm−1.<p>Les spectres enregistrés à l'aide du montage femto-FT-CEAS ont permis d'attribuer<p>plus de 1000 transitions rovibrationelles d'échantillons de CO2 enrichis en 17O,<p>d'OCS, CS2, H12C13CD, et CH3CCH. Les bandes suivantes ont été enrégistrées :<p>pour 12C17O2, les bandes 30013e, 30012e, 30011e, 31113e, 31113f, 31112e, 31112f,<p>et 31111e; pour 17O12C18O, les bandes 30013e, 30012e, et 30011e; pour 16O12C32S,<p>les bandes 540, 0, 501, 0, 511, 1e, 511, 1f, 601, 0, 460, 0, 421, 0, 431, 1e, 431, 1f,<p>521, 0, 341, 0, 351, 1e, 351, 1f, 302, 0, 312, 1e, 312, 1f, 402, 0, 322, 2e, et 322, 2f;<p>pour 16O12C34S, les bandes 501, 0 et 302, 0; pour 16O13C32S, la bande 302, 0 ;pour<p>16O12C33S, la bande 302, 0; pour 12C32S2, les bandes 0403, 0114, 3003 et 2203; pour<p>32S12C34S, la bande 3003. Les conventions de notation vibrationelles utilisées ici sont<p>pour CO2, ν1 ν2 l ν3 n où les bandes vibrationelles perturbées par la résonance de<p>Fermi ν1 2ν2 sont ordonnées selon n par ordre décroissant d'énergie. Pour l'OCS,<p>les conventions de notation sont ν1 ν2 ν3, l et pour le CS2, ν1 νl2 ν3. Leur analyse<p>spectrale a été réalisée, aboutissant à de nouvelles constantes rovibrationelles ou des<p>constantes améliorées par rapport à celles de la littérature. Les raies rovibrationnelles<p>attribuées sont données. L'analyse des spectres de H12C13CD et de CH3CCH a étéréalisée par l'équipe du Pr. L. Fusina (Université de Bologne, Italie).<p>L'expérience a aussi été installée autour d'un jet supersonique, enregistrant les<p>structures rotationnelles des bandes vibrationelles ν5 + ν9 de C2H4, 3ν3 de N2O et<p>ν1 + ν3 de H12C13CH en abondance naturelle, toutes avec une température rotationelle<p>inférieure à 35 K.<p>Finalement, un programme de simulation de ligne de base a été écrit.<br>Doctorat en Sciences de l'ingénieur<br>info:eu-repo/semantics/nonPublished
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Ibrahim, Mohamad. "Étude de la réactivité du dimère hétéronucléaire PdTi avec le monoxyde de carbone et du titane atomique avec CO et H2O en matrice d’argon et par spectroscopie vibrationnelle FTIR Spectra and structures of the Pdm-CO complexes: An infrared matrix isolation and density functional study Infrared Spectroscopy and Density Functional Theory Investigations of PdTi Heterodimer Reactivity with Carbon Monoxide Isolated in Solid Argon." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS643.
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Le sujet de cette thèse est l'étude de la réactivité de métaux de transition avec les ligands CO et H2O en utilisant la technique d’isolation en matrices d’argon à 12 K et la spectroscopie infrarouge à transformée de Fourier. Nous avons étudié la réaction du dimère hétéronucléaire PdTi avec le CO et nous avons pu identifier les molécules PdTi-CO, TiPd-CO, PdTi(CO)2 et PdTi(CO)3. L’irradiation dans le visible permet de convertir la molécule PdTi-CO avec un CO lié au Ti à la molécule TiPd-CO avec un CO lié au Pd. Dans la deuxième partie de cette thèse nous avons étudié la réaction du titane atomique avec deux ligands différents, le CO et H2O. Cette réaction est spontanée et nous avons ainsi caractérisé les molécules HTiOH-CO et HTiOH-(CO)2, essentiellement à l’aide des molécules isotopiques du CO et de H2O.Des calculs ont été effectués avec la théorie de la fonctionnelle de la densité (DFT). La comparaison entre les données théoriques et expérimentales nous a permis de déterminer les paramètres géométriques et électroniques des espèces étudiées<br>The purpose of this thesis is the study of transition metal atoms reactivity with the CO and H2O ligands using argon matrix isolation at 12 K and the Fourier Transform Infrared Spectroscopy. We have studied the reaction between the heteronuclear PdTi dimer with CO and we have identified the PdTi-CO, TiPd-CO, PdTi(CO)2, and PdTi(CO)3 molecules. Irradiation in the visible leads to the conversion from PdTi-CO with a Ti-CO bond to TiPd-CO with a Pd-CO bond. In the second part of this thesis, we have studied the reaction between the atomic titanium and the CO and H2O ligands. This is a spontaneous reaction and we have characterized the HTiOH-CO and HTiOH-(CO)2 molecules essentially with the help of the isotopic CO and H2O molecules. Calculations have been made with the density functional theory (DFT). The comparison between theoretical and experimental data allowed us to determine the geometric and electronic parameters of the studied species
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Öhman, Maria. "An in situ spectro-electrochemical study of aluminium/polymer interfaces : development of ATR-FTIR and its integration with EIS for corrosion studies." Licentiate thesis, KTH, Fibre and Polymer Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4237.
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<p>In order to extend the applications of aluminium, organic coatings may be applied on sheet materials, for instance for corrosion protection or aesthetic surface finish purposes in the automotive and construction industries, or on foil materials in the flexible packaging industry.</p><p>The most common mechanisms for deterioration and structural failure of organically coated aluminium structures are triggered by exposures to the surrounding environment. Despite the great importance to elucidate the influence of exposure parameters on a buried aluminium/polymer interface, there is still a lack of knowledge regarding the mechanisms that destabilise the structure. It is generally believed that a detailed <i>in situ</i> analysis of the transport of corroding species to the buried interface, or of surface processes occurring therein, is most difficult to perform at relevant climatic and real-time conditions.</p><p>In this work, Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR) in the Kretschmann-ATR configuration was successfully applied to <i>in situ</i> studies of the transport of water and ionic species through polymer films to the aluminium/polymer interface upon exposure to ultra pure deionised water and to a 1 M sodium thiocyanate (NaSCN) model electrolyte. Other main processes distinguished were the formation of corrosion products on the aluminium surface and swelling of the surface-near polymer network. Hence, <i>in situ</i> ATR-FTIR was capable to separate deterioration-related processes from each other.</p><p>To perform more unambiguous interpretations, a spectro-electrochemical method was also developed for<i> in situ</i> studies of the buried aluminium/polymer interface by integrating the ATR-FTIR technique with a complementary acting technique, Electrical Impedance Spectroscopy (EIS). While transport of water and electrolyte through the polymer film to the aluminium/polymer interface and subsequent oxidation/corrosion of aluminium could be followed by ATR-FTIR, the protective properties of the polymer as well as of processes at the aluminium surface were simultaneously studied by EIS. The integrated set-up provided complementary information of the aluminium/polymer sample investigated, with ATR-FTIR being sensitive to the surface-near region and EIS being sensitive to the whole system. While oxidation/corrosion and delamination are difficult to distinguish by EIS, oxide formation could be confirmed by ATR-FTIR. Additionally, while delamination and polymer swelling may be difficult to separate with ATR-FTIR, EIS distinguished swelling of the polymer network and also identified ultimate failure as a result of delamination.</p><p>The capability of the integrated ATR-FTIR / EIS <i>in situ</i> technique was explored by studying aluminium/polymer systems of varying characteristics. Differences in water and electrolyte ingress could be monitored, as well as metal corrosion, polymer swelling and delamination.</p>
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Siepka, Damian. "Development of multidimensional spectral data processing procedures for analysis of composition and mixing state of aerosol particles by Raman and FTIR spectroscopy." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10188/document.
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Les méthodologies de traitement de données multidimensionnelles peuvent considérablement améliorer la connaissance des échantillons. Les techniques spectroscopiques permettent l’analyse moléculaire avancée d’échantillons variés et complexes. La combinaison des techniques spectroscopiques aux méthodes de chimiométrie trouve des applications dans de nombreux domaines. Les particules atmosphériques affectent la qualité de l’air, la santé humaine, les écosystèmes et jouent un rôle important dans le processus de changement climatique. L’objectif de cette thèse a été de développer des outils de chimiométrie, simples d’utilisation, permettant de traiter un grand nombre de données spectrales provenant de l’analyse d’échantillons complexes par microspectrométrie Raman (RMS) et spectroscopie d’absorption IRTF. Dans un premier temps, nous avons développé une méthodologie combinant les méthodes de résolution de courbes et d’analyse multivariée afin de déterminer la composition chimique d’échantillons de particules analysées par RMS. Cette méthode appliquée à l’analyse de particules collectées dans les mines en Bolivie, a ouvert une nouvelle voie de description des échantillons. Dans un second temps, nous avons conçu un logiciel facilement accessible pour le traitement des données IRTF et Raman. Ce logiciel inclue plusieurs algorithmes de prétraitement ainsi que les méthodes d’analyse multivariées adaptées à la spectroscopie vibrationnelle. Il a été appliqué avec succès pour le traitement de données spectrales enregistrées pour divers échantillons (particules de mines de charbon, particules biogéniques, pigments organiques)<br>Sufficiently adjusted, multivariate data processing methods and procedures can significantly improve the process for obtaining knowledge of a sample composition. Spectroscopic techniques have capabilities for fast analysis of various samples and were developed for research and industrial purposes. It creates a great possibility for advanced molecular analysis of complex samples, such as atmospheric aerosols. Airborne particles affect air quality, human health, ecosystem condition and play an important role in the Earth’s climate system. The purpose of this thesis is twofold. On an analytical level, the functional algorithm for evaluation of quantitative composition of atmospheric particles from measurements of individual particles by Raman microspectrocopy (RMS) was established. On a constructive level, the readily accessible analytical system for Raman and FTIR data processing was developed. A potential of a single particle analysis by RMS has been exploited by an application of the designed analytical algorithm based on a combination between a multicurve resolution and a multivariate data treatment for an efficient description of chemical mixing of aerosol particles. The algorithm was applied to the particles collected in a copper mine in Bolivia and provides a new way of a sample description. The new user-friendly software, which includes pre-treatment algorithms and several easy-to access, common multivariate data treatments, is equipped with a graphical interface. The created software was applied to some challenging aspects of a pattern recognition in the scope of Raman and FTIR spectroscopy for coal mine particles, biogenic particles and organic pigments
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Öhman, Maria. "An in situ spectro-electrochemical study of aluminium/polymer interfaces : development of ATR-FTIR and its integration with EIS for corrosion studies /." Stockholm : Fibre and Polymer Technology (Fiber- och polymerteknologi), Kungliga tekniska högskolan, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4237.
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Luneau, Jean-Charles. "Mise au point d'une méthode spectrale non intrusive (FTIR) pour l'étude de la cinétique de décomposition thermique des explosifs : Application à l'octogène." Orléans, 1999. http://www.theses.fr/1999ORLE2049.
Full textAbstract:
Ce travail avait pour premier objectif de doter le laboratoire d'un dispositif experimental d'analyse in situ des produits de decomposition des explosifs soumis a une sollicitation thermique. Ces materiaux, de part leur caractere hautement energetique, peuvent etre a l'origine d'accidents pyrotechnique majeurs. Pour cette raison, la securite qui leur est lie est toute particuliere et demande le developpement de code de calculs qui permettront de definir la reponse de l'explosif lors d'une sollicitation accidentelle donnee. La technique de spectrophotometrie infrarouge a transformee de fourier a ete choisie pour cette etude. Elle est couplee a une cellule experimentale permettant l'application de la sollicitation sur l'echantillon, ainsi qu'un diagnostic in situ portant sur les gaz de decomposition du materiau. Une application de ce dispositif experimental est proposee sur la decomposition thermique d'un explosif secondaire, de la famille des nitramines : l'octogene. Apres identification des produits de decomposition de cette molecule, une calibration des gaz suivants est effectuee : n 2o, no 2, no, ch 2o, hcn, co, co 2 et h 2o. L'etalonnage est realise pour des pressions totales de 80 et 200 kpa. L'etude quantitative des produits de decomposition de l'octogene permet de valider le dispositif experimental, via le bilan massique. Nous sommes donc susceptibles de suivre les profils des produits de decomposition en fonction du temps mais egalement de remonter a l'evolution de la masse de l'echantillon au cours de la sollicitation. Le programme experimental porte sur l'influence de la matrice de gaz. L'argon, l'azote et l'air sont ainsi etudies dans un domaine de temperature compris entre 463 k et 553 k, pour une pression de 80 kpa. Une etude de l'influence de la pression de la matrice de gaz est egalement menee, entre 80 et 200 kpa. Des constantes de vitesse de decomposition sont proposees en fonction des conditions experimentales. Ces constantes sont de deux types : pseudo-ordre un et prout-tompkins modifie. Cette derniere fait appel a un modele de cinetique heterogene de germination en chaines branchees. Dans le cas des constantes de vitesse de pseudo-ordre un, une expression de la periode d'induction a la decomposition est indispensable pour rendre compte du comportement global lors de la sollicitation. Ce travail constitue une premiere approche de l'etude de la decomposition thermique des explosifs. Il apparait necessaire de mener des etudes plus precises concernant le processus de decomposition, ceci passant par une evolution du dispositif experimental.
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Didriche, Keevin. "High resolution infrared spectroscopy: setting up an experiment to investigate small clusters." Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210437.
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The role of clusters in planetary atmospheres and the interstellar medium is potentially important. Investigating such a role requires basic experimental information, however lacking. The goal of this thesis was to develop an efficient experimental set-up to produce clusters in the laboratory in concentrations large enough to allow their high resolution spectra to be recorded, thus providing the necessary data allowing the physico-chemical properties of the clusters to be studied.<p>The study of this subject however suffers from the lack of basic experimental data. The goal is therefore to produce clusters in the laboratory in concentration large enough to record their high resolution spectrum. This is the initial aim of the present thesis.<p>During this work, we have built and extensively tested a new experimental set-up called FANTASIO (``Fourier trANsform, Tunable diode and quadrupole mAss spectrometers interfaced to a Supersonic expansIOn'). With the help of this new device, various experiments on jet-cooled species have been performed.<p>The cartography of the supersonic expansion was established, using the mass spectrometer as a moving pressure probe. This enabled us to characterize the geometrical properties of the supersonic jet produced by circular and slit nozzles and to determine the position of the virtual nozzle. The effect of the axisymmetric expansion geometry on the R(0) lineshape in the nu_3 band of N_2O, recorded by FTIR, was also investigated.<p>The rotational temperature of the jet-cooled molecules was determined to be a few K by measuring the intensity of lines in spectra recorded by FTIR spectroscopy.<p>Vibrational energy transfer occuring in the expansion between N_2O molecules and different collision partners was investigated on the nu_2+nu_3-nu_2 band of N_2O, again using FTIR spectroscopy. The trend of these transfers was found to be related to the energy difference between the v_2=1 level of N_2O and the closest vibrational state in the collision partner, with the largest population.<p>The sensitivity of the set-up was enhanced by a factor of 5 by increasing the absorption path length, using a multipass system. A procedure to remove the residual gas contribution from the IR spectra was developped, based on the mass spectrometer. Thanks to this sensitivity increase, broadband absorption features of clusters were observed for a C_2H_2-Ar mixture in circular and slit expansions.<p>The optical sensitivity of FANTASIO was again increased by the implementation of the CW-CRDS system. The enhancement over FTIR was calculated to be over a factor 750. Thanks to this drastic improvement, spectral signatures of various clusters were recorded, such as C_2H_2-Ar, C_2H_2 multimers, C_2H_2-N_2O and C_2H_2-CO_2, at high resolution.<p>The role of clustering in generating unusual line shapes of acetylene in an axisymmetric expansion was investigated. We demonstrated that C_2H_2 aggregates produced in the expansion are responsible for central dips observed in the monomer absorption. These acetylene clusters thus appear to be formed in the centre of the expansion, while, unexpectedly, acetylene-Ar complexes are formed at the edge of the conical expansion.<p>Various research prospects were explored during this thesis thanks to the FANTASIO device, opening new research directions. FANTASIO is today operational and defines a useful tool to achieve the study of small clusters by infrared spectroscopy./<p><p>Le rôle des agrégats dans les atmosphères planétaires et dans le milieu interstellaire est potentiellement important. Cependant, les études sur ce sujet souffrent du manque de données expérimentales. Le but de cette thèse était de développer un dispositif expérimental efficace pour produire au laboratoire des agrégats en quantité suffisante pour permettre l'enregistrement de leur spectre infrarouge à haute résolution et donc l'étude de leurs propriétés physico-chimiques.<p>Durant ce travail, nous avons construit et testé un nouveau dispositif expérimental appelé FANTASIO, basé sur un jet supersonique couplé à un spectromètre de masse, un spectromètre à transformée de Fourier et un système CRDS. Grâce à cet appareillage, différentes expériences sur des molécules à basse température ont été menées.<p>L'expansion supersonique a été cartographiée en utilisant le spectromètre de masse comme une sonde de pression mobile. Cette cartographie nous a permis d'établir les propriétés géométriques des jets supersoniques produits par les orifices circulaire et de type fente, et de déterminer la position de l'orifice virtuel. L'effet de la géométrie de l'expansion sphérique sur le profil de la raie R(0) de la bande nu_3 de N_2O, enregistré par FTIR, a aussi été étudié.<p>Une température rotationnelle de quelques K a été déterminée pour les molécules refroidies en jet supersonique par mesure de la distribution d'intensité de raies dans les spectres enregistrés par FTIR.<p>Le transfert d'énergie vibrationnelle entre des molécules de N_2O et différents partenaires collisionnels a été étudié en analysant l'intensité de la bande nu_2+nu_3-nu_2 de N_2O, enregistré également par spectroscopie FTIR. Il a été trouvé que la tendance de ces transferts est liée à la différence d'énergie entre le niveau v_2=1 de N_2O et l'état vibrationnel le plus proche et le plus peuplé du partenaire collisionnel.<p>La sensibilité du dispositif a été augmentée d'un facteur 5 dû à l'allongement du chemin d'absorption, grâce à l'utilisation d'un système multipassage. Une procédure basée sur l'utilisation du spectromètre de masse et visant à enlever la contribution du gaz chaud résiduel dans les spectres infrarouges a été mise au point. Grâce à cette augmentation de sensibilité, des structures d'absorption non résolues d'agrégats ont été observées dans des expansions en trou et en fente d'un mélange de C_2H_2-Ar.<p>La sensibilité optique de FANTASIO a encore été augmentée par l'ajout au dispositif d'un système CW-CRDS. L'amélioration par rapport au spectromètre à transformée de Fourier a été calculée comme étant supérieure à un facteur 750. Grâce à cette importante amélioration, les signatures spectrales de divers agrégats, tels que C_2H_2-Ar, des multimères de C_2H_2, C_2H_2-N_2O et C_2H_2-CO_2, ont été enregistrées à haute résolution.<p>Le rôle de l'agrégation dans la génération de profils de raie inhabituels dans une expansion en trou de l'acétylène a été étudié. Nous avons démontré que les agrégats de C_2H_2 produits dans le jet supersonique sont responsables des creux observés dans le profil d'absorption du monomère. Ces agrégats apparaissent donc comme étant formés au centre de l'expansion, tandis que, de manière inattendue, les agrégats de C_2H_2-Ar sont formés aux bords de l'expansion conique.<p>Plusieurs idées de recherche ont été explorées durant cette thèse grâce au dispositif FANTASIO, ouvrant de nouvelles directions de recherche. FANTASIO est aujourd'hui opérationnel et se présente comme un outil utile dans l'étude des petits agrégats par spectroscopie infrarouge.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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Yurdakul, Yorulmaz Sema. "Investigation Of Emissions And Combustion Kinetics Of Waste Wood Samples With Thermal And Spectral Methods." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607570/index.pdf.
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The mechanisms and kinetics of combustion of waste wood as well as the phases during combustion processes are important to eliminate these wastes without any possible damage to environment. In the present study, combustion mechanisms, activation energy and pre-exponential constants, and phases of combustion were investigated for untreated natural pine and treated Medium Density Fiberboard (MDF), plywood and particleboard samples that involve some chemicals and additives. Waste wood samples were heated in air at 10, 20 and 30oC/min heating rates in a Thermo Gravimetric Analyzer (TGA) from room temperature to 900oC. Thermogravimetry (TG) and Derivative Thermogravimetry (DTG) curves for all samples were obtained. The gases formed during combustion reactions were directly fed to a Fourier Transform Infrared Spectroscopy (FTIR) instrument coupled to TGA. Emission characteristics of the samples were determined in-situ by using the FTIR spectrums.
As a result of TG analysis, thermal decomposition of treated samples was observed at lower temperatures as compared to the untreated pine sample because of the catalyzing effects of the chemicals in the treated samples.
Therefore, there were less flammable products, lower weight losses in the main oxidation region, decrease in the max. weight loss temperatures and formation of more char for treated samples as compared to untreated pine sample. In other words, chemicals used during production of these samples lead to decrease in the combustibility of the treated samples.
Thermal kinetic constants for the samples were calculated by using Coats Redfern and Broido Methods. In order to find out the mechanisms responsible for the oxidation of the waste wood samples in different regions, six solid state mechanisms of Coats Redfern Method were tested.
As a result of FTIR analysis of the emitted gases from TG analysis, several chemical groups were detected from pine and treated samples. Combustion of all samples revealed some gases containing aromatics, C-H groups, CO2 and CO. However, there were some toxic and carcinogenic gases like formaldehyde, isocyanate group, ammonia, phenyl group and benzoylbromide among the emissions of treated samples which need utmost attention when recovering energy from treated waste woods.
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NOTARSTEFANO, VALENTINA. "Development of new molecular tools for the characterization of human Granulosa cells: new implications for the research on human infertility." Doctoral thesis, Università Politecnica delle Marche, 2018. http://hdl.handle.net/11566/252927.
Full textAbstract:
Nella routine della riproduzione assistita, la selezione degli ovociti si basa sulle loro caratteristiche
morfologiche, nonostante la scarsa correlazione tra tali parametri e la competenza dell’ovocita. Pertanto,
la ricerca si sta concentrando sull’identificazione di marker che possano supportare l’attuale metodica di
valutazione, in particolare studiando le cellule della Granulosa (GCs), che svolgono compiti fondamentali
all’interno del microambiente del follicolo: produzione di estradiolo e progesterone, regolazione
dell’avanzamento della meiosi e dell’attività trascrizionale dell’ovocita, produzione di nutrienti essenziali
per l’ovocita, e accumulo di metaboliti secreti. Pertanto, la progressione degli step della follicologenesi
dipende strettamente dalla comunicazione bidirezionale tra ovocita e le cellule somatiche che lo
circondano.
Lo studio delle GCs ha messo in luce molti aspetti circa le funzionalità ovariche, la follicologenesi, e i
meccanismi con cui fattori endogeni ed esogeni possono alterare questi delicati processi.
In questo senso, lo scopo principale del presente PhD è stato quello di caratterizzare le GCs, applicando
per la prima volta la tecnica Fourier Transform Infrared Microspectroscopy (FTIRM), in modo da
sviluppare un nuovo metodo per valutare la qualità degli ovociti umani. Questo potrebbe rappresentare
uno strumento nuovo, affidabile e oggettivo per la valutazione della qualità degli ovociti nella routine
della riproduzione assistita.
Oltre al tema principale, sono state applicate le tecniche FTIRM, Raman Microspectroscopy e qPCR per
studiare i meccanismi di intaccamento del metabolismo, della composizione biochimica e dell’attività
cellulare causati da fattori endogeni ed esogeni, in particolare l’invecchiamento riproduttivo,
l’endometriosi ovarica e inquinanti plastici.
Le informazioni ottenute su queste cellule contribuiscono alla comprensione dei meccanismi di
danneggiamento della follicologenesi, tramite un approccio multidisciplinare che ha visto l’accoppiamento
di analisi spettroscopiche e qPCR. Grazie ai risultati ottenuti, è stato proposto un approccio innovativo
per l’analisi della qualità degli ovociti tramite caratteristiche spettrali delle GCs, suggerendo la possibilità
di un’applicazione dell’FTIRM come strumento diagnostico di facile utilizzo nella routine di riproduzione
assistita.<br>In assisted reproductive routine, oocyte selection is based on its morphological features, which seem not
to be related to its intrinsic competence. Hence, several efforts have been made to identify markers to be
added to the actual evaluation, in particular focusing on the crucial roles of Granulosa cells (GCs) in the
follicular microenvironment: production of estradiol and progesterone, regulation of the meiosis steps and
the transcriptional activity in the oocyte, production of essential nutrients for the oocyte, and
accumulation of secreted metabolites. Hence, the progression through the steps of folliculogenesis heavily
relies upon bi-directional interactions between germ cells and the surrounding somatic cells.
The study of GCs has shown to be determining to highlight particular features of ovarian mechanisms
and folliculogenesis, and also to identify the endogenous and exogenous factors that can impair these
delicate processes.
In this sense, the main aim of the PhD project was to characterize GCs, applying for the first time Fourier
Transform Infrared Microspectroscopy (FTIRM) to develop a method for evaluating the quality of human
oocytes. This could represent a new, reliable and objective tool for oocyte quality assessment in assisted
reproduction routine.
Besides this main topic, the impairment induced by endogenous and exogenous factors on the biochemical
composition, metabolism and cellular activity of GCs was also investigated by FTIRM, Raman
Microspectroscopy and qPCR, shedding new light on the mechanisms governing folliculogenesis. In
particular, the research was focused on the impairment determined by reproductive aging, ovarian
endometriosis, and plastic pollutants.
The information obtained on GCs contribute to the understanding of the mechanisms of impairment of
folliculogenesis, by a multidisciplinary approach made of spectroscopic analysis and qPCR. Thanks to the
results, an innovative approach to evaluate oocyte quality by spectral features of GCs was proposed,
suggesting the possibility to apply FTIRM as a clinical feasible diagnostic tool in assisted reproduction
routine.
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Sanii, Laurie Shireen. "Application of Spectroscopy to Protein Characterization." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7641.
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There are two contributions of this thesis. The first contribution, described in chapters one through six, involves studing the relationship between the protein packing structure of bacteriorhodopsin (bR) and its function as a proton pump. In 2002, a novel crystallization method published by Bowie and Farham resulted in an unusual antiparallel monomeric packing structure of bicelle bacteriorhodopsin (bcbR) crystals, the spectroscopic properties of which had not been studied. In this thesis, these bicelle bR crystals are investigated to better understand how the changes in the protein tertiary structure affect the function. Specifically: Does the retinal Schiff base retain its ability to isomerize in this unusual protein packing structure of bR? How is the hydration of its binding pocket affected? Does the protein retain the ability to undergo the photocycle and pump protons? If so, how are the rates of the deprotonation/reprotonation of the Schiff base affected by the antiparallel monomer packing structure of the protein? Is Asp85 still the proton acceptor during the deprotonation process of the photocycle? The second contribution of the thesis, described in chapter seven, describes the surface attachment and growth of the biofilm formed by the pathogenic bacterium Streptococcus pneumoniae using attenuated total reflection/Fourier transform infrared spectroscopy (ATR/FTIR). This organism was chosen for its clinical significance; it is one of the organisms suspected in forming biofilms in individuals who develop otitis media, one of the most common causes of ear infections of childhood. In contrast to previous ATR/FTIR experiments examining the formation of biofilms on surfaces, this method is unique in that it combines two techniques - ATR/FTIR and Epifluorescence microscopy which when used together allow for the simultaneous monitoring of the IR spectrum of the S. pneumoniae biofilm as it develops and as provides a method for quantifying total and viable cell counts at various stages during the development.
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Goodall, Rosemary Anne. "Spectroscopic studies of Maya pigments." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16958/1/Rosemary_Goodall_Thesis.pdf.
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The Maya of Central America developed a complex society: among their many achievements they developed a writing system, complex calendar and were prolific builders. The buildings of their large urban centres, such as Copan in Honduras, were decorated with painted stucco, moulded masks, carving and elaborate murals, using a range of coloured pigments. In this study the paints used on the buildings of Copan and some ceramic sherds have been investigated, non-destructively, using micro-Raman spectroscopy, micro-ATR infrared spectroscopy, environmental scanning electron microscopy with energy dispersive X-ray analysis (ESEM-EDX) and FTIR-ATR imaging spectroscopy. The paint samples come from four buildings and one tomb covering three time periods in the four hundred year history of Copan. The main pigment used in the red paint on these samples was identified as haematite, and the stucco as a mixture of calcite particles dispersed throughout a calcite-based lime wash stucco. The composition and physical nature of the stucco changed through time, indicating a refining of production techniques over this period. A range of minor mineral components have been identified in each of the samples including rutile, quartz, clay and carbon. The presence and proportion of these and other minerals differed in each sample, leading to unique mineral signatures for the paint from each time period.
Green and grey paints have also been identified on one of the buildings, the Rosalila Temple. The green pigment was identified as a celadonite-based green earth, and the grey pigment as a mixture of carbon and muscovite. The combination of carbon and mica to create a reflective paint is a novel finding in Maya archaeology. The high spatial resolution of the micro-FTIR-ATR spectral imaging system has been used to resolve individual particles in tomb wall paint and to identify their mineralogy from their spectra. This system has been used in combination with micro-Raman spectroscopy and ESEM-EDX mapping to characterize the paint, which was found to be a mixture of haematite and silicate particles, with minor amounts of calcite, carbon and magnetite particles, in a sub-micron haematite and calcite matrix. The blending of a high percentage of silicate particles into the haematite pigment is unique the tomb sample. The stucco in this tomb wall paint has finely ground carbon dispersed throughout the top layer providing a dark base for the paint layer. Changing paint mixtures and stucco composition were found to correlate with changes in paint processing techniques and building construction methods over the four hundred years of site occupation.
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Goodall, Rosemary Anne. "Spectroscopic studies of Maya pigments." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16958/.
Full textAbstract:
The Maya of Central America developed a complex society: among their many achievements they developed a writing system, complex calendar and were prolific builders. The buildings of their large urban centres, such as Copan in Honduras, were decorated with painted stucco, moulded masks, carving and elaborate murals, using a range of coloured pigments. In this study the paints used on the buildings of Copan and some ceramic sherds have been investigated, non-destructively, using micro-Raman spectroscopy, micro-ATR infrared spectroscopy, environmental scanning electron microscopy with energy dispersive X-ray analysis (ESEM-EDX) and FTIR-ATR imaging spectroscopy. The paint samples come from four buildings and one tomb covering three time periods in the four hundred year history of Copan. The main pigment used in the red paint on these samples was identified as haematite, and the stucco as a mixture of calcite particles dispersed throughout a calcite-based lime wash stucco. The composition and physical nature of the stucco changed through time, indicating a refining of production techniques over this period. A range of minor mineral components have been identified in each of the samples including rutile, quartz, clay and carbon. The presence and proportion of these and other minerals differed in each sample, leading to unique mineral signatures for the paint from each time period.
Green and grey paints have also been identified on one of the buildings, the Rosalila Temple. The green pigment was identified as a celadonite-based green earth, and the grey pigment as a mixture of carbon and muscovite. The combination of carbon and mica to create a reflective paint is a novel finding in Maya archaeology. The high spatial resolution of the micro-FTIR-ATR spectral imaging system has been used to resolve individual particles in tomb wall paint and to identify their mineralogy from their spectra. This system has been used in combination with micro-Raman spectroscopy and ESEM-EDX mapping to characterize the paint, which was found to be a mixture of haematite and silicate particles, with minor amounts of calcite, carbon and magnetite particles, in a sub-micron haematite and calcite matrix. The blending of a high percentage of silicate particles into the haematite pigment is unique the tomb sample. The stucco in this tomb wall paint has finely ground carbon dispersed throughout the top layer providing a dark base for the paint layer. Changing paint mixtures and stucco composition were found to correlate with changes in paint processing techniques and building construction methods over the four hundred years of site occupation.
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Champion, Patrick D. "An analysis of Fourier transform infrared spectroscopy data to predict herpes simplex virus 1 infection." Atlanta, Ga. : Georgia State University, 2008. http://digitalarchive.gsu.edu/math_theses/62/.
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Thesis (M.S.)--Georgia State University, 2008.<br>Title from title page (Digital Archive@GSU, viewed July 29, 2010) Yu-Sheng Hsu, committee chair; Gary Hastings, Jun Han, committee members. Includes bibliographical references (p. 41).
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Sheh, Jhi-Ming, and 謝智明. "FTIR spectra of EUV Photo-desorbed H2O+CO2+NH3 Mixed Ice System at." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/83568485270639130761.
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碩士<br>國立中央大學<br>物理研究所<br>91<br>Abstract
Experimental results on the spectral identification of new infrared absorption features and the changes of their absorbances produced through vacuum ultraviolet-extreme ultraviolet(VUV-EUV) photon-induced chemical reactions in the H2O-NH3-CO2 mixed ices at 16K are obtained. The compositions, i.e., H2O:NH3:CO2= 6:1:1 were chosen in this work. Zeroth order white light from the SEYA beamline at Synchrotron Radiation Research Center (SRRC) in Hsinchu was used to provide required VUV-EUV photons. A FTIR spectrometer was employed to obtain the in-situ IR spectra produced through VUV or EVU photolysis of a given ice sample. Ultraviolet photolysis of these ices produces a variety of photoproducts including XCN, CO, CH3OH, C2H6, CH3, H2CO, H2CO3, and possibly HCOOH, CH4 and CO3. However, despite of so many photoproducts were produced by the feeding of strong white light photon energies C2H5OH and C3H8 were still not been found in these experiments.
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Chen-Ning, Chiu, and 邱振寧. "The FTIR spectra analysis of CO & CH chemical compound production of 15keV H3+ ion bombard on CO & CO2 & CH3OH ice mixed with H2O." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/78405595651824168186.
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碩士<br>國立中央大學<br>物理研究所<br>99<br>There are many interstellar ices in the galaxy, and its main composition includes H2O, NH3, CH3OH, CH4, CO, CO2, etc. Under the low temperature (10K -100K), these molecules tend to attach to the surfaces of the interstellar particles or the meteorites, and then become interstellar ice. Meanwhile, there are also many particles (with energy to some degree) that ejected by other stars in the universe, like the solar wind of the solar system. When bombarded with these energetic particles, the molecule structure of the interstellar ice could be changed and produce organic matters. Those interstellar ices on the surfaces of the meteorite, which had turned into organic matters, may fall on a planet with the meteorite, and bring the organic matters to that planet. This could make a significant change to the evolution of the planet, especially for the planet where the organic matters never exist before.
The mechanism of the reaction that produces organic matter out of ice crystal is the main topic that we wanted to probe into in this essay. In our experiment, we utilized the cryogenic technique (24 K) and the ultra-high vacuum (6×10-10 torr) to simulate the environment of outer space. And we used H3+ ions (15keV) to bombard the chemical compounds (the ice crystal) with CH-bonds or CO-bonds. The chemical compounds, including CH4 and CO2, mixed with H2O in various proposition are the controlled variables in the experiment. Finally, we used FTIR to scan the ice crystal, both before and after the bombardment, and then analyze the quantity of the CO、 CO2 and CH3OH bonds produced under the different conditions.
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Liao, Yi-Cyuan, and 廖鐿全. "The FTIR spectra analysis of OH & CH chemical compound production of 15keV H3+ ion bombard on H2O & D2O ice mixed with CH-bond or CO-bond." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/fff37v.
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碩士<br>國立中央大學<br>機械工程研究所<br>96<br>Our planetary system is composed of the collapse of dense molecular cloud,and it is attracted each other by gravity. The collapse of dense molecular cloud are composed of gases and sub-micrometer sized grains. The main composition of the interstellar solid material include H2O, CO, CO2, CH3OH and CH4 etc,.These interstellar ice after the energetic particle bombarded that are being come from the solar wind and how evolves its interstellar ice is the main place where we probe into.
In our experiment is to utilize ultra high vacuum ( 1×10-9 Torr) and cryogenic technique ( 18K) to simulate the environment of outer space, it use H3+ ion to bombard the ice that include CH or CO bond chemical compound and H2O or D2O mixed ,and the energy as 15keV. It used FTIR to scan the frozen and infrared spectrum of the ice crystal.
And then analyze the quantity of the chemical compound OH(D) and CH(D) bond that produced or consumed ,and analyze the influence of the mixing and proportions of H2O and D2O isotope with OH(D) and CH (D) bond. Finally, to do the discussion of OH(D) (3200~3000 cm-1) that is owned in common.
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Lin, Chih-Lung, and 林志龍. "The FTIR spectra analysis of CO & CO2 production of 15keV H3+ ion bombard on H2O & D2O ice mixed with CH-bond or CO-bond chemical compound." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/yqw864.
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碩士<br>國立中央大學<br>機械工程研究所<br>96<br>ABSTRACT
It has about 15% visible matter in the galaxy, and this visible matter is composed of 99% gas and 1% sub-micrometersized grains. In outer space environment, the temperature range is between 10K and 100K.In the low temperature environment, gases form into ice on the grains. The interstellar ice is composed primarily of H2O、NH3、CH3OH、CH4、CO and CO2, etc. The complex organic compounds can be created in the ice via irradiation process.
We use 15keV H3+ bombard CO- or CH- compounds with H2O and D2O ice mixtures. After H3+ bombard CO- or CH- compounds with H2O and D2O ice mixtures. We observe CO(2136 cm-1)and CO2 (2339 cm-1) on all FTIR spectra. In order to compare CO(2136 cm-1)and CO2 (2339 cm-1) production yield, we use different mixture proportion (1:1、1:3),mixture solution (H2O、D2O) and ice sample. Therefore, this thesis does analysis.
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Zhang, Jun. "Analysis and characterization of consumer products by FTIR, Raman, chemometrics, and two dimensional ATR-FTIR correlation spectroscopy." 2009. http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.000051431.
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Der, Wu Yi, and 吳奕德. "The Study on Polymer Crystallization Behavior and Polymer Interaction with Lithium Salt Using FTIR Spectrum." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/90772093150588945304.
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博士<br>國立交通大學<br>應用化學系所<br>95<br>The morphology and specific interaction within polymer micro-structure have been a topic of intense interest in polymer science due to their fine application. However, there are many polymer physical properties cannot study from the general instrument, such as intrinsic crystallinity, molecular interaction in quantity so far. It would be a choke point for polymer science to study the molecular structure of polymer in detail.
The Fourier transfer infrared spectroscopy is a powerful tool used to identify the functional group, morphology, and interaction… etc. The FTIR has been widely described in terms of many scientists for a long time. Therefore, in this study, we will choose two systems to study the polymer intrinsic crystallization behavior of syndiotactic-polystyrene and intrinsic interaction within polymer electrolyte by using Fourier transfer infrared spectroscopy. The results in this research have demonstrated it is more in detail that the Fourier transfer infrared spectroscopy could observe the crystallinization behavior and interaction with Lithium of polymer matrix.
The experiment work in this dissertation was divided into two areas:
(1) The first, the crystallinity and crystallization behavior of syndiotactic polystyrene ��- and ��-crystals have been thoroughly examined using the Fourier Transform Infrared. It is shown that absorptivity ratio of respective absorbances of “α-crystal/amorphous, a�恁� and “β-crystal/amorphous, a�牷� can be quantitatively determined using FTIR spectra ranging from 865 to 820 cm-1. Results from curve fitting show that both absorptivity ratios of a�� and a�� are 0.178�b0.005 and 0.272�b0.005 for ��- and ��-crystal absorbances, respectively. The crystallization rate and crystallinity of ��-crystal calculated from the absorptivity ratios are higher than that of ��-crystal crystallized at 240 ℃ for the same isothermal duration in thin film sample. The formation of ��-crystal is thermodynamically more favorable while of ��-crystal is kinetically more favorable from FTIR spectra.
Crystallization of �� and ��-form crystals of syndiotactic polystyrene can be achieved from cold- and melt-crystallization at 264 ℃ in thin film samples (less than 10�慆), respectively. The normal crystal transformation of ��- to ��-form is not found in the cold-crystallization in s-PS thin film samples, result in exclusively ��-form crystals. This allows to the individual lamellae of a-form crystal to extend continuously with further crystallization time at 264℃ in s-PS thin film samples. On the contrary, only ��-form crystals are formed in melt-crystallization at 264 ℃, in either thin film or bulk s-PS samples.
(2) The second, the interaction behavior of polymer electrolytes composed of poly (vinyl pyrrolidone) (PVP) and Lithium Perchlorate (LiClO4) has been investigated in details by solid state NMR and Fourier transfer infrared spectroscopy. It is found that the N atom of the PVP polymer is able to donate its lone pair electrons toward the C=O group and results in higher basicity of the C=O group. The complex bond of Li+—C=O is comparted into two types: the tight primary complex bond of Li+—C=O; and the secondary complex where Li+ loosely complexed with several C=O groups simultaneously. The secondary complex is dominant when the [Li : O] ratio is greater than 0.281. The ClO4- anion is free in the diluted PVP/LiClO4 electrolyte. When the LiClO4 concentration is increased, the ClO4- anion will interacts with both N quasi-cation and/or Li+ cation. Solvated Li+ and “free” ClO4- ions are more favorable in diluted electrolyte; whereas neutral solvation—shared ion pair formation increases the incremental addition the LiClO4.
Take polyester electrolyte system as further study. Characterization and interaction behavior between Li+ ion and C=O groups of a series polyester electrolyte have been thoroughly examined using Fourier Transform Infrared (FTIR). The “free/Li+ bonded” C=O absorptivity coefficient of the LiClO4/Polyester can be determined quantitatively using FTIR spectroscopy ranging from 1800 to 1650 cm-1 at 80oC. Results from curve fitting show that the “free/Li+ bonded” C=O absorptivity coefficient is 0.144 ± 0.005. The ion shows a strong interaction with the C=O group of polymer electrolyte; and a limit value of 95% “Li+ bonded” C=O is approached in the polymer electrolyte system when the Li+ ion equivalent fraction is about 0.28. The molecular structure of polyester electrolyte does not affect significantly the efficiency of interaction between Li+ ion and C=O.
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Chen, Chien-Chung, and 陳建中. "Using Carbon-Fluorine polymer as wet etching mask to fabricate Si sawtooth grating and measuring with FTIR and Raman Spectrum." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/26269818935940169994.
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碩士<br>國立臺灣大學<br>電子工程學研究所<br>98<br>In this work, we fabricate Si sawtooth and triangle grating by wet etching .Then study the transmittance of infrared light and the intensity of Raman spectrum.
By electron beam lithography and anisotropic wet etching principle, we fabricate one-dimensional grating structure on the Si substrate, then observed by SEM. By Changing length of mask and etching time, we successfully fabricate sawtooth grating. During the experiment we also found that the residue after RIE process can be used as wet etching mask which was a kind of Carbon-Fluorine polymer, and then analyze it by XPS .
Then measuring the samples by FTIR and Raman spectrum. Comparing the infrared transmittances with different depths and angles of silicon grating.. We use light momentum conservation and dispersion relation to find out some wavelength position of extraordinary transmission phenomenon. there are some extraordinary transmission wavelength which can’t be explained by the theory. By Raman spectrum, we found that the sharp grating has stronger signal of Raman spectrum.
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Guedes, Daniela dos Santos. "How old are you? An attempt of estimating age at death through FTIR-ATR analysis of human bones and teeth." Master's thesis, 2019. http://hdl.handle.net/10316/87907.
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Dissertação de Mestrado em Química Forense apresentada à Faculdade de Ciências e Tecnologia<br>Em contextos forenses, a estimativa do perfil biológico em restos humanos esqueletizados é de extrema importância numa perspetiva ética, legal e criminal. A previsão da idade cronológica à morte em adultos é considerada uma das maiores lacunas em Antropologia Forense, tendo em conta que os métodos antropológicos macroscópicos costumam apresentar grandes intervalos nas suas estimativas. Os esqueletos humanos de indivíduos distintos apresentam idiossincrasias a nível atómico-molecular, induzidas por fatores intrínsecos e extrínsecos, tais como a composição e organização dos tecidos, a taxa de remodelação, a degradação do colagénio e processos diagenéticos. Estes fatores promovem diferentes características e, consequentemente, afetam o esqueleto de maneira diferente. Recorrendo à espetroscopia de Infravermelho em Refletância Total Atenuada foram analisadas amostras humanas de fémur, úmero, metatarso, costela, parietal e dentes. Foi levada a cabo uma exploração quimiométrica para avaliar o seu potencial como indicador da idade cronológica em adultos. Tal foi realizado através da caracterização estrutural dos esqueletos e pela procura de padrões, com o objetivo de determinar as regiões mais representativas do espetro e as potenciais diferenças estatísticas entre índices para tipos de osso, sexo, classes etárias e idade. Deste modo, uma análise estatística exploratória e inferencial foi implementada. Os índices quimiométricos investigados neste estudo foram os seguintes: CI, C/P, API, BPI, C/P, v4PO4/Amida I e v1PO4/Amida I. A combinação destas análises exploratória e inferencial permitiu obter informações espetrais distintas. Através da análise estatística exploratória, realizada através da análise de componentes principais, foram observadas diferenças entre tipos de osso relativamente a variações espetrais – nomeadamente na intensidade das bandas v3(CO3)B, amida I e amida II. Apenas para as amostras de dentes foram encontradas discriminações entre faixas etárias, através da banda v1,v3(PO43-). A análise estatística inferencial, por seu lado,para além da diferenciação por tipos de osso foram detetadas diferenças estatisticamente significativas para as classes etárias e idade cronológica, tanto para ossos como para dentes, de acordo com os índices espetrais IC e C/C. Os valores dos erros médios absolutos foram elevados tanto para as faixas etárias (0.25-1.84 para os ossos longos; 0.26-1.85 para as costelas; e 0.93-10.6 para os dentes) como para a idade cronológica (4.45-25.86 para ossos longos e 23.57-24.45 para os dentes).<br>In forensic contexts, the estimation of the biological profile of skeletal humanremains is of extreme importance from the ethical, legal and criminal perspective. The prediction of chronological age at death in adults is considered one of the biggest struggles of Forensic Anthropology, since anthropological macroscopic methods usually have large estimation intervals. The human skeleton from distinct individuals presents idiosyncrasies at the atomic and molecular level, induced by intrinsic and extrinsic factors, such as the tissue composition and organization, remodelling rate, collagen degradation and diagenetic pathways, which promote different features affecting the skeleton differently. Femur, humerus, metatarsal, ribs, parietal and teeth samples were analyzed through Fourier Transform Infrared spectroscopy in Attenuated Total Reflectance mode. Anexploration of chemometrics as a potential indicator of chronological age in adults wascarried out. This was performed by skeletal structural characterization and searching for patterns in order to determine the most representative regions of the spectra and the potential statistical differences among indices per bone types, sex, age cohorts and age.To achieve this, an exploratory and inferential statistical analysis was implemented. The chemometric indices investigated in this study were the CI, C/P, API, BPI, C/P, v4PO4/AmideI and v1PO4/Amide I. The combination of this exploratory and inferential analysis enabled to obtain distinct spectral information. Through the exploratory statistical analysis, achieved through principal components analysis, differences among bone types were observed relative to spectral variations – namely in the intensity of the v3(CO3)B, amide I and amide II bands. Only for teeth discrimination among age cohorts was revealed, through the v1,v3(PO43-) domain.Whereas via inferential statistical analysis, poor ability was found for age determination. Reasonable results regarding the prediction of age cohorts or chronological age from both bones and teeth were only obtained by using the CI and C/C spectral indices. High mean absolute errors were obtained for age cohorts (0.25-1.84 for long bones; 0.26-1.85 for ribs; and 0.93-1.06 for teeth) and for chronological age (4.45-25.86 for long bones and 23.57-24.45 for teeth).
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Huang, Chia Sheng, and 黃家聖. "Interpenetrating network membranes of poly (2-hydroxylethyl meth-acrylate) (poly HEMA) and poly (vinyl alcohol) (PVA) in various ratios were prepared by UV radiation and treated with glutaraldehyde (GA). From the spectral change of FTIR, the hydroxyl grou." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/33056050865582555044.
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碩士<br>長庚大學<br>化工與材料工程研究所<br>93<br>Interpenetrating network membranes of poly (2-hydroxylethyl meth- acrylate) (poly HEMA) and poly (vinyl alcohol) (PVA) in various ratios were prepared by UV radiation and treated with glutaraldehyde (GA). From the spectral change of FTIR, the hydroxyl groups disappeared and an acetal ring and ether linkage were formed for the reaction between the hydroxyl groups of PVA and GA. From the stress-strain curve, it was found that the tensile strength and elongation increased with PVA content on the PVA / poly (HEMA) membranes. After crosslinking with GA, the membranes became brittle, whereas the thermal stability increased about 20-100℃. Two glass transition temperature were found for the PVA / poly (HEMA) membranes. It means that PVA and poly (HEMA) are incompatible in this study. Due to the hydrophilicity of poly (HEMA), the water content in the membranes increased with increasing the content of poly (HEMA) in the membranes. After treatment with GA, the contact angle on the PVA / poly (HEMA) membranes decreased. The permeation of creatinine, 5-fluorouracil (5-FU) and vitamin B12 through at 37℃ were conducted. The permeability increased with increasing poly (HEMA) content in the membranes.