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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Využití NIR spektroskopie při kontrole jakosti pomazánkových másel.

Žákovská, Adéla January 2010 (has links)
No description available.
62

Využití NIR spektroskopie ke kontrole jakosti sýrů typu mozzarella

Musilová, Lenka January 2011 (has links)
No description available.
63

Viabilidade do uso da técnica de espectroscopia de reflexão com radiações visíveis e infravermelhas como método auxiliar para o diagnóstico pulpar

Provasi, Camila January 2016 (has links)
Orientador: Prof. Dr. Emery Cleiton Cabral Correia Lins / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Engenharia Biomédica, 2016. / A polpa dental, considerada um tecido mole, é o tecido mais interno do dente. Sua função principal é garantir a formação de dentina (dentinogênese) durante toda a vida do indivíduo. Sendo assim,a informação sobre sua saúde é de extrema relevância no ambiente clínico odontológico. Uma vez que a polpa do dente é diagnosticada não saudável por consequência de infecções e/ou traumas, o procedimento clínico sugere a realização de tratamento com remoção total do tecido degradado. Dessa maneira, a proposta do presente projeto de pesquisa foi a proposição de um novo método diagnóstico utilizando-se da espectroscopia de reflexão com radiações no visível e no infravermelho próximo (VIS/NIR e NIR de 350nm a 1700nm) para discriminação de polpas humanas sadias e polpas patológicas indicadas para procedimento endodôntico. Para isso, fez-se uso do modelo estatístico da Análise de Componentes Principais (PCA) nas bandas espectrais VIS/NIR e NIR para proposições de modelos matemáticos que diferenciasse os dois grupos de amostras. Os modelos apresentaram que a distinção destes dois grupos é possível com uma taxa de acertos de 94,7% no NIR e 95% no VIS/NIR. Além disso, no VIS/NIR a diferenciação dos grupos também se dava ao analisar o comprimento de onda onde ocorria o pico da emissão: observou-se que os picos do grupo sadio patológico estavam sempre acima de 700nm enquanto que os picos do grupo patológico mantinham abaixo de 700nm. Com tudo, o objetivo do presente projeto de pesquisa foi alcançado: os grupos de polpas sadias e patológicas puderam ser separados ao utilizar radiações VIS/NIR e NIR pela técnica de espectroscopia de reflexão, seja pela análise estatística da PCA por parte dos espectros no NIR ou pela análise colorimétrica do pico de emissão por parte dos espectros no VIS/NIR. / The dental pulp, a soft tissue, is the innermost tissue of the tooth. Its main function is to ensure the formation of dentin (dentinogenesis) throughout the life of the individual. Therefore, the information about their health is extremely relevant in the clinical dental environment. Since the pulp of the tooth is diagnosed unhealthy as a result of infections and/or trauma, the clinical procedure suggests performing treatment with total removal of the degraded tissue. In this way, the proposal of the present research project was the proposal of a new diagnostic method using reflection spectroscopy with visible and near infrared (VIS/NIR and NIR from 350nm to 1700nm) for discrimination of healthy human pulps and pathological pulps indicated for endodontic procedure. For this, we used the statistical model of Principal Component Analysis (PCA) in the spectral bands VIS/NIR and NIR for propositions of mathematical models that differed between the two groups of samples. The models showed that the distinction between these two groups is possible with a success rate of 94.7% in NIR and 95% in VIS/NIR. In addition, in the VIS/NIR group differentiation also occurred when analyzing the wavelength where the emission peak occurred: it was observed that the peaks of the pathological healthy group were always above 700nm whereas the peaks of the pathological group maintained Below 700nm. However, the objective of the present research project was reached: the groups of healthy and pathological pulps could be separated by using VIS/NIR and NIR radiation by the reflection spectroscopy technique, or by the statistical analysis of PCA by the NIR spectra or by the colorimetric analysis of the emission peak by the VIS/NIR spectra.
64

Utilização de métodos quimiométricos para análise quantitativa de glibenclamida comprimido utilizando as espectroscopias de infravermelho próximo e raman– desenvolvimento e validação de uma estratégia de pat

OLIVEIRA, Antonio Diógenes Pereira de 28 February 2014 (has links)
Submitted by Ramon Santana (ramon.souza@ufpe.br) on 2015-03-10T18:52:55Z No. of bitstreams: 2 DISSERTAÇÃO Antônio Diogenes Pereira de Oliveira.pdf: 2346315 bytes, checksum: d08a9632e55bd4d72db587264a53fc92 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-10T18:52:55Z (GMT). No. of bitstreams: 2 DISSERTAÇÃO Antônio Diogenes Pereira de Oliveira.pdf: 2346315 bytes, checksum: d08a9632e55bd4d72db587264a53fc92 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2014-02-28 / A glibenclamida é uma sulfoniluréia de segunda geração usada no tratamento do diabetes mellitus tipo 2. É um medicamento que é administrado em baixa dose terapêutica (5mg) na forma de comprimidos, condição em que pequenas variações na concentração do ativo farmacêutico podem influenciar a qualidade do produto. O monitoramento da produção deste produto requer um maior número de amostras analisadas em menor tempo possível, de forma a garantir maior uniformidade em todo o lote produzido ao longo da linha de produção. Este requerimento é possível através da implantação das Tecnologias Analíticas de Processo – PAT, com o uso de metodologias rápidas, exatas e precisas, como a utilização das espectroscopias no infravermelho próximo (NIR) e Raman, associadas à quimiometria. O objetivo do presente estudo foi desenvolver e validar métodos analíticos com uso das espectroscopias NIR e Raman associadas com a calibração multivariada para utilização no monitoramento de processos em uma estratégia de implantação de PAT na indústria farmacêutica. Foram produzidos dois modelos multivariados, PLS e PLS/JK para cada uma das técnicas NIR e Raman, em seguida os modelos foram validados, através de uma proposta que atende a legislação farmacêutica e a aplicação multivariada do método. Os espectro foram pré-processados com 1ª derivada, com filtro Savitzky-Golay, polinômio de segunda ordem e janela de 13 e 7 pontos para NIR e Raman, respectivamente, considerando parte do espectro original. Os valores obtidos para RMSEP dos modelos estiveram compreendidos entre 0,07 a 0,11 para ambas as técnicas, demonstrando exatidão adequada a sua aplicação no PAT. Parâmetros como sensibilidade, seletividade, precisão, linearidade demonstraram atendimento aos requerimentos da validação, com exceção da robustez para o tempo de exposição da amostra no Raman foi um parâmetro crítico e não pôde ser alterado. Os modelos de calibração obtidos atendem aos requisitos da tecnologia analítica de processo, e encontram-se validados para uso nas rotinas de controle de qualidade.
65

Monitoring of multicomponent pharmaceutical powders in a compression process : development of a robust real time monitoring tools / Suivi du procédé de compression d'un mélange de poudres pharmaceutiques : développement d'outils robustes pour un suivi en temps réel

Marchao Palmeiro Durao, Pedro Filipe January 2017 (has links)
La façon dont l'industrie pharmaceutique développe et manufacture ses produits a évolué au cours de ces dernières années. L'environnement réglementaire auquel elle est contrainte a provoqué ce changement dans le but de doter de technologies de pointe dans ses différentes activités. L’encouragement pour utiliser les technologies d’analyse de procédé (PAT) afin d’implémenter le concept de « Quality By Design » (QbD) est l’exemple le plus significatif de ce nouveau paradigme. Lentement, les industries implémentent ces technologies pour de nouveaux produits, mais également pour certains produits déjà existants, bénéficiant ainsi de leurs avantages. Pour implémenter des PAT dans un procédé, plusieurs étapes doivent être franchies, de l’étude de faisabilité des instruments jusqu’à l’approbation règlementaire. Cette thèse décrit l’étude initiale (faisabilité et développement de modèles) avant toute demande d’autorisation d’utilisation d’outils PAT (proche infra-rouge (NIR), caméra RGB et fluorescence induite par laser (LIF)) pour suivre le procédé de compression d’un mélange commercial comprenant plusieurs ingrédients. Après avoir établi le potentiel de ces différents outils, des modèles quantitatifs calculés par régression par moindres carrés partiels (PLS) ont été développés pour suivre les composants ayant une concentration aussi faible que 0,1 w/w%, avec un coefficient de détermination (R2) de 0,95. Il a également été démontré que l’utilisation conjointe de données de plus d’un outil améliorait la précision du modèle. La spécificité de chacun des outils a également été évaluée à l’aide de plan d’expériences factoriels complets pour lesquels les modèles ont été construits en faisant varier simultanément la concentration de différents éléments. Même dans ces conditions, les modèles construits ont montré une précision acceptable, en considérant les critères d’acceptation utilisés pour les produits alimentaires comme les multivitamines. Le travail présenté dans cette thèse a contribué à la publication de trois articles et de trois présentations orales. En plus de l’établissement de la preuve de concept, ce qui augmente les opportunités pour tester d’autres sondes, la possibilité de suivre en ligne la composition quantitative dans la ligne d’alimentation de la presse a également été établi. Dans ce dernier cas, tous les outils sont suffisamment précis pour suivre au moins un des composants, même si celui-ci est présent en faible concentration et fait partie d’un mélange de plusieurs composants. Conséquemment, l’industrie peut utiliser ses connaissances pour suivre le procédé de compression de façon plus adéquate en augmentant l’éventail des outils utilisés à cet effet. Une recherche fondamentale pourrait également investiguer les phénomènes tels que la ségrégation afin mieux les comprendre. / Abstract : The way pharmaceutical industry develops and manufactures their products has been changing in recent years. The regulatory environment that they are obligated to comply has been pushing this change in order to endow this activity with state of art technology. The encouragement of the use of process analytical technology (PAT) to build the quality right from the design (QbD) is perhaps the most significant example of the new paradigm. The manufacturers are implementing this technology in new and existing products and benefiting from their advantages. To implement PAT in a process, many steps must be taken (from the study of feasibility of the instruments until regulatory approval). This thesis describes the initial study (feasibility and model developments), prior to any submission of authorization, of the use of PAT tools (Near-Infrared (NIR), Red Green Blue (RGB) camera and Light Induced Fluorescence (LIF)) to monitor the compression process of a commercial multi-component blend. After the potential of these tools was assessed, quantitative Partial Least Squares (PLS) models were able to be developed to monitor components with a concentration as low as 0.1 w/w % with a R2 of 0.95. It was also proved that combining data from more than one tool was benefit for the accuracy of the model. The tools were also evaluated to their specificity by using a full factorial design where the models were built with simultaneous variations of concentration of some of the components. Even in this challenging case, the models built remained with an acceptable accuracy, considering the acceptance criteria used for dietary products such as multi-vitamins. The work developed in this thesis contributed to the publication of 3 articles and 3 communications. Along with the proof of concept that it provided - which enlarged the opportunities for testing other probes - it also proved that is possible to monitor in-line the components in the feed frame. In this latter case, all the tools were accurate enough to monitor at least one component even if they are present in low concentration and part of multi-component blends. Therefore, the industry can use this knowledge to monitor the compression process more adequately, increasing the range of tools used for the effect. Fundamental research can also be investigated as phenomena like segregation can be more accurately identified.
66

Forenzn­ analza pdy metodami FTIR a NIR s multivariaÄn­ analzou / The forensic analysis of soil by FTIR and NIR with multivariate analysis

Nawrath, Pavel January 2020 (has links)
This diploma thesis is about forensic multivariate soil analysis in the localities Ostrava and Tinec. 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 (FâAAS). 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).
67

Hodnocení změn při dozrávání a skladování ovoce s využitím metod NIR spektroskopie

Šnurkovič, Petr January 2016 (has links)
The dissertation thesis is focused on investigation of possibilities of usage NIR spectroscopy for nutritional composition of fruit and vegetables evaluation. The basic nutritional components of fruit and vegetables, methods of apples, peaches and tomatoes storage are characterized in the literary section. The history of infrared spectroscopy, present, principles and types of NIR spectroscopy analyses are described in detail. The possibilities of usage of NIR spectroscopy in food industry aimed on fruit and vegetables quality evaluation are also described in the literary section. Changes of fruit and vegetables nutritional composition during ripening are evaluated in the experimental part. Evaluated fruit and vegetables were apples (variety Rubinola), tomatoes (variety Dagmar) and peaches (variety Redhaven). Changes in the total polyphenols content, titratable acids, soluble dry matter, malic acid, ascorbic acid, citric acid, peel firmness and apple flesh firmness were evaluated. Calibration models were prepared from the gained data using the NIR spectroscopy method. The changes of stored fruits nutritional composition were evaluated using the created calibration models. Soluble dry matter, titratable acids, ascorbic acid and flesh firmness of different apple, peach and tomato varieties can be determined fast and exactly according to the data. The accuracy of models for total polyphenols and peel firmness is significantly influenced by the number of calibration standards. The accuracy of models for malic and citric acids is influenced by the concentration of these components in fruits.
68

Synthese, Eigenschaften und funktionale Anwendungen von NIR absorbierenden Squarainen / Synthesis, Properties and Functional Applications of NIR Absorbing Squaraines

Mayerhöffer, Ulrich January 2012 (has links) (PDF)
Zusammenfassend lässt sich festhalten, dass die in dieser Abreit vorgestellten Squaraine herausragend gute NIR-Absorptions- und NIR-Emissionseigenschaften aufweisen, die sie für zahlreiche Anwendungen interessant machen. Darüber hinaus konnte gezeigt werden, dass ihre besondere cis-Konfiguration und ihr daraus resultierendes Dipolmoment zu vorteilhaften Anordnungen in dünnen Filmen und in Blends mit PCBM führen. Diese Strukturen zeigen für dipolare Moleküle beeindruckende Exzitonen- und Ladungstransporteigenschaften, die vielversprechende Anwendungen in der organischen Elektronik wie in hier untersuchten lösungsprozessierten BHJ-Solarzellen oder auch in OFETs erwarten lassen. / Concluding the results of the present work, the here descript acceptor-substituted squaraines exhibit extremely favourable NIR absorption and emission properties which make them to ideal candidates for a broad variety of functional applications. Furthermore, the additional acceptor functions provoke a cis-configuration, resulting in a permanent ground state dipole moment which becomes a dominating ordering force in supramolecular arrangements of those squaraine dyes in solution as well as in thin organic films and in blends with PCBM. These structures feature unprecedented exciton and charge carrier mobilities for dipolar molecules with promising properties for the application in organic photovoltaics, as demonstrated in this work and for possible future applications such as OFETs.
69

Die Auswirkung der ADHS Erkrankung auf die Bearbeitung einer kognitiven „Set Shifting“ Aufgabe / The impact of ADHD working on a cognitive Set Shifting task

Hein [geb. Gienk], Stella Anneliese January 2021 (has links) (PDF)
Das Ziel der vorliegenden Arbeit war die Untersuchung der Impulsivität bei adulten Patienten mit ADHS. Es wurden 19 adulte Patienten mit ADHS und 20 gesunde Kontrollprobanden, die nach Alter, Geschlecht und Schulabschluss vergleichbar waren, untersucht. Wir nutzten ein kognitives Set Shifting Paradigma und erfassten die Verhaltensdaten (Reaktionszeit und Fehler) sowie hirnphysiologische Änderungen mittels funktioneller Nahinfrarotspektroskopie (fNIRS). Als „Region of Interest“ (ROI) legten wir den dorsolateralen präfrontalen Kortex (dlPFC) fest. Zusätzlich erfolgte eine Selbsterfassung der Impulsivität mittels BIS 11, SPSRQ und UPPS Fragebogen. Auf der Verhaltensebene zeigten die Patienten mit ADHS im Vergleich zu den gesunden Kontrollprobanden eine verlängerte Reaktionszeit. Die Bearbeitung einer Shift Aufgabe führte bei beiden Probandengruppen zu einer verlängerten Reaktionszeit sowie einer erhöhten Fehlerzahl im Verhältnis zu einer No Shift Aufgabe. In der Erhebung der funktionellen Daten konnten wir einen signifikanten Unterschied zwischen den Gruppen im Bereich der ROI feststellen. Die gesunden Kontrollprobanden wiesen eine erhöhte Hirnaktivität im dlPFC auf. In den Fragebögen zur Selbsterfassung der Impulsivität erreichten die Patienten in den meisten Unterskalen Werte, die mit erhöhter Impulsivität einhergehen. / The aim of this study was to investigate impulsivity in adult patients with ADHD. We examined 19 adult patients with ADHD and 20 healthy subjects, which were of comparable age, gender and level of education. We used a cognitive Set Shifting paradigm, recorded behavioral data (reaction time and mistakes) and as well as changes in brain activation with a functional near-infrared spectroscopy. As „region of interest“ we used the dorsolateral prefrontal cortex. Additionally, the impulsivity was measured with self-rated impulsivity questionnaires BIS 11, SPSRQ and UPPS. Behavioral results showed a heightened reaction time for the ADHD group as compared with the healthy subjects. We saw an extended reaction time and error rate in all subjects solving Shift trials compared to No Shift trials. Brain activity showed a robust dorsolateral prefrontal activity pattern for the healthy subjects. The ADHD patients reached significantly higher values for impulsivity in the most subscales of the questionnaires.
70

Near Infrared Investigation of Polypropylene-Clay Nanocomposites for Further Quality Control Purposes-Opportunities and Limitations

Witschnigg, A., Laske, S., Holzer, C., Patel, Rajnikant, Khan, Atif H., Benkreira, Hadj, Coates, Philip D. 31 August 2015 (has links)
Yes / Polymer nanocomposites are usually characterized using various methods, such as small angle X-ray diffraction (XRD) or transmission electron microscopy, to gain insights into the morphology of the material. The disadvantages of these common characterization methods are that they are expensive and time consuming in terms of sample preparation and testing. In this work, near infrared spectroscopy (NIR) spectroscopy is used to characterize nanocomposites produced using a unique twin-screw mini-mixer, which is able to replicate, at ~25 g scale, the same mixing quality as in larger scale twin screw extruders. We correlated the results of X-ray diffraction, transmission electron microscopy, G′ and G″ from rotational rheology, Young’s modulus, and tensile strength with those of NIR spectroscopy. Our work has demonstrated that NIR-technology is suitable for quantitative characterization of such properties. Furthermore, the results are very promising regarding the fact that the NIR probe can be installed in a nanocomposite-processing twin screw extruder to measure inline and in real time, and could be used to help optimize the compounding process for increased quality, consistency, and enhanced product properties

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