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1

Schwalb, Björn. "Dynamic transcriptome analysis (DTA)." Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-147748.

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2

Diemer, Mouriac Halen. "DTA : discriminador de tráfego ATM." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2001. http://hdl.handle.net/10183/3181.

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As redes ATM têm se constituído na solução tecnológica ideal para o desenvolvimento da RDSI-FL. O ATM foi desenvolvido para dar suporte, com altas velocidades e com garantia de qualidade, a uma ampla variedade de serviços. A demanda por serviços de comunicação de dados, em velocidades maiores do que as redes de pacotes atuais são capazes de oferecer, tem crescido rapidamente, estimulando o desenvolvimento da tecnologia ATM, que tem sido muito promissora, devida a sua flexibilidade e eficiência. Para dar suporte à comunicação de dados em redes ATM, foram desenvolvidas soluções, como a emulação de redes locais (LANE), a interconexão de redes locais (LAN) e metropolitanas (MAN), e o protocolo IP sobre ATM. O ATM utiliza multiplexação estatística (assíncrona) para inserir os dados nos canais de comunicação de forma otimizada. Esta técnica, permite atender uma quantidade maior de fontes heterogêneas sob num único canal, porém, pode causar congestionamento na rede. O uso da multiplexação estatística, aliada à necessidade de garantir níveis de qualidade diferentes, para cada tipo de serviço, torna necessária a adoção de uma combinação de técnicas de controle de tráfego e congestionamento. Com este propósito, foram desenvolvidos diversas funções e mecanismos, como, por exemplo, controle de acesso (CAC), controle dos parâmetros de uso (UPC), descarte seletivo de células e conformação de tráfego (TS), os quais necessitam conhecer as características do tráfego emitido pela fonte. Por esta razão, toda e qualquer conexão ATM está associada a um contrato de tráfego, que especifica as exigências do usuário, quanto à qualidade de serviço (QoS) a ser oferecida pela rede, através de um descritor de tráfego. O trabalho apresentado nesta dissertação, tem por objetivo propor uma metodologia capaz de discriminar um fluxo de células ATM arbitrário, visando a obter os parâmetros descritores de UPC do mesmo. A discriminação de tráfego é relevante à medida que todos os usuários de redes ATM necessitam, de alguma forma, determinar os parâmetros que caracterizam seu fluxo, para poder negociar o contrato de trafego. Infelizmente, a maioria das aplicações ATM, não tem condições prévias de fornecer dados sobre o comportamento do fluxo que geram. Para estas situações, estamos propondo um Discriminador de Tráfego ATM (DTA), que infere a partir de uma amostra inicial do fluxo um conjunto mais provável de parâmetros, os quais constituirão o descritor de tráfego da fonte (STD).
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3

Hoffman, Roland. "Measuring ΔH Using DSC, TGA & DTA." TopSCHOLAR®, 1990. https://digitalcommons.wku.edu/theses/2500.

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The purpose of this study was to obtain greater accuracy in the measurement of the heat of reaction by combining data from various thermal analysis techniques. Conventional equations that calculate heat of reaction are limited because they do not take in to account mass change. Therefore, an enhanced equation was developed to integrate mass (weight) change to provide greater accuracy. The path chosen to implement this new equation employed simultaneous Thermogravimetric / Differential Thermal Analysis (TG/DTA) that could provide both ΔT and weight data simultaneously. Computer programs were written in C and Pascal languages to provide communication capabilities between computers and to calculate heat of reaction using various equations. This included a qualitative to quantitative (ΔT to ΔH) conversion which was performed to the DTA data file to which the enhanced equation was applied. Various samples were used to test and monitor the performance of the developed equations.
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4

Sui, Yihang. "Scenario analyzer for real-time Dynamic Transportation Assignment (DTA) systems." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/119337.

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Thesis: S.M. in Transportation, Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2018.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 71-74).
The optimization of network control strategies using real-time Dynamic Traffic Assignment systems typically utilizes short-term predictions of the network state within a rolling horizon framework. However, there exist several network control instruments (such as incentive schemes under daily budget constraints) whose optimization necessitate generating predictions beyond the "roll period" and for the entire day. This work addresses the aforementioned problem by proposing a "Scenario Analyzer" to extend the horizon for the optimization problem by providing relatively accurate predictions and forecasting results for the extended horizon. The Scenario Analyzer module adopts a data driven approach, and is formulated as a matching problem utilizing an archived historical database. The archived historical database includes the data from DTA systems as master data table, daily run table and historical scenario table. The matching algorithms use the historical scenario table and master data table to pair the current run feature(s) with historical runs feature(s); after finding a match, the current run will be stored at the daily run table. The matching problem may be solved using different statistical or machine learning algorithms, in terms of: 1) single time step feature matching 2) multiple time steps features matching. The performance of the proposed scenario analyzer is examined for the optimization of an app-based travel incentive scheme to reduce system wide energy consumption (referred to as Tripod) in the Boston CBD network. The k-NN and KL divergence matching algorithms are tested for a simulation period of 6 AM - 9 PM. Results indicate that the scenario analyzer with k-NN outperforms KLD algorithm probably because KLD need more data points to fully-develop the time-series properties. Among all the traffic features using in the matching algorithms, the cumulative energy consumption is the best indicator for similarity comparison.
by Yihang Sui.
S.M. in Transportation
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5

Hsieh, Chang-yu. "Identifying cavitation regions using spectral and itensity dta : application to HIFU." Thesis, University of Oxford, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.572517.

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The high power intensities in HIFU often result in bubble production, either through cavitation or boiling, which are believed to be a primary contributor to tissue necrosis. Bubbles are associated with the bright hyperechoic regions in ultrasound B-mode images. As the only changes observed on tissue are subtle during treatment, some HIFU therapy protocols rely on the observation of significant brightness changes as the indicator of tissue lesions. The occurrence of a distinct hyperechoic region around the focus is often associated with cavitation. In general, the hyperechoic regions show good correlation with ablated tissue (observed directly following subsequent removal of the tumour in an operation, or using MRI), but the sensitivity of this techniques is sub-optimal. Reliable detection of cavitation and a method to distinguish between different types of events is therefore, an important goal for better control of the treatment. This thesis presents a novel method to provide detection of cavitation activity as an aid to assisting treatment. The image intensity information is used to identify hyperechoic regions spatially and temporally. However, hyperechoic regions may appear for reasons other than cavitation - for example because of tissue interfaces. The spectral information is useful to distinguish from other events and thermal generation of bubbles. Thus the spectral estimation methods are becoming of increasing interest in early and robust detection of cavitation activity. There are three main contributions related to this thesis: identifying the boundaries and maintaining a history of cavitation events from their brightness and intensity statistics through using a probabilistic method, determining not just the presence of cavitation but also its local changes at a high spatial resolution through analysing spectrally the RF signals from the imaging transducer on a pixel by pixel basis, and finally combining the advantages of both methods to improve the overall reliability of automatic cavitation detection. In addition, the spectral information extracted here is capable potentially of distinguishing between cavitation and boiling. The method is assessed using a simulation of a synthesised cavitation, and the applied to detect cavitation following HIFU in ex-vivo calf liver.
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6

Ramos, Luiz Antonio. "Investigação do comportamento térmico e de polimorfismo do anti-histamínico loratadina." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-04082011-143805/.

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O comportamento térmico, a obtenção e caracterização de formas cristalinas do anti-histamínico loratadina foram investigado. A escolha do anti-histamínico loratadina como objeto de estudo resulta do seu interesse farmacológico. A loratadina é a Denominação Comum Internacional (DCI) dada ao etil 4-(8-cloro-5,6-dihidro-11H-benzo[5,6]cicloheptano[1,2-b]piridino-11-ilideno)-1-piperidinocarboxilato, que é um potente antialérgico e anti-histamínicos tricíclico, não-sedativo de ação prolongada. Formas cristalinas foram preparadas e estudadas com vista à identificação de formas polimórficas. Os solventes utilizados na preparação das soluções foram: álcool etílico, acetonitrila, álcool isopropílico, acetona, álcool metílico, éter isopropílico, éter metil terc-butílico, tolueno, clorofórmio. A cristalização foi realizada por evaporação do solvente em diferentes temperaturas. A calorimetria exploratória diferencial (DSC), termogravimetria e termogravimetria derivada (TG/DTG), análise térmica diferencial (DTA), difração de raios X (DRX) e a ressonância magnética nuclear (RMN) foram às técnicas utilizadas na caracterização das formas polimórficas. A maioria das amostras obtidas pelas técnicas de cristalização consistiam de misturas de formas cristalinas, contendo, por vezes, formas metaestáveis e formas amorfas. Identificaram-se duas formas cristalinas como polimorfos da loratadina, cujas curvas DSC mostrou interconversão entre ambas.
The preparation, characterization and thermal behavior of the crystalline forms of the antihistamine loratadine has been developed. The selection of loratadine as an object of study results from its pharmacological interest. Loratadine is the International Common Denomination (ICD) given to ethyl 4-(8-chloro-5,6-dihydro-11H-benzo [5,6] cyclohepta[1,2-b]pyridin-11-ylidene)-1-piperidinecarboxylate, a potent anti-allergic and anti-histamincs, tricyclic, non-sedating long acting. Crystalline forms were prepared and studied for the identification of polymorphic forms. The solvents used in preparing the solutions were: ethanol, acetonitrile, isopropyl alcohol, acetone, methyl alcohol, isopropyl ether, methyl tert-butyl ether, toluene, chloroform. The crystallization was performed by evaporating the solvent at different temperatures. The differential scanning calorimetry (DSC), thermogravimetry and derivative thermogravimetry (TG/DTG), differential thermal analysis (DTA), X-ray diffraction (XRD) and nuclear magnetic resonance (NMR) techniques were used to characterize the polymorphic forms. Most of the samples obtained by the crystallization were mixtures of crystalline forms, containing sometimes forms metastable and amorphous forms. It was identified as two crystalline polymorphic forms of loratadine, whose DSC curves demonstrated that they are interconvertable.
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7

Dulina, I., L. Klochkov, M. Danilenko, and A. Ragulya. "Synthesis of Ni/NiO Nanopowder by Thermal Decomposition of Nickel Acetate Amine." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/34819.

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Ni/NiO nanopowders have been synthesized using thermal decomposition of nickel acetate hexaammine in air. Obtained powders have been characterized by IR-spectroscopy, XRD and TG, DTA, DTG and HR TEM. Thermal decomposition of nickel ammine complexes occurs with forming nickel hydroxide, carbonate and hydroxocarbonate ammines precursors. Mean particle size of nickel and nickel oxide phases in powders depends on temperature. In the temperature range from 350 to 500 degrees Celsius the particle size of nickel oxide has grown from 5 to 25 nm and nickel from 50 to 55 nm. Particle size of 5 nm for nickel hydroxide ammine remained unchanged with temperature. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34819
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8

Nunes, Ronaldo Spezia. "Estudo do comportamento térmico de alguns aditivos alimentares por TG/DTG, DTA e DSC." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-25082009-161837/.

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Estudos termoanalíticos de alguns aditivos alimentares da classe dos realçadores de sabor foram desenvolvidos visando avaliar sua estabilidade e resistência durante o preparo de alimentos a quente assim como investigar os eventuais intermediários de decomposição que poderiam resultar destes processos. Os sais foram obtidos de fontes industriais ou sintetizados e submetidos à caracterização por análise elementar, espectrometria vibracional na região do infra-vermelho, termogravimetria/termogravimetria derivada, análise térmica diferencial e em alguns casos, calorimetria exploratória diferencial. Foram estudados o ácido glutâmico e seus sais de amônio, lítio e sódio mono e dissubstituídos. Em todos os casos observou-se uma conversão a piroglutamato após desidratação dos sais monossubstituídos, a qual ocorre via a a-carboxila. A estabilidade térmica destes sais foi da ordem de 190-200 °C. No caso dos sais dissubstituídos de lítio e sódio não houve conversão ao piroglutamato pois as duas carboxilas estão salificadas. Os glutamatos de magnésio, cálcio estrôncio e bário, também foram preparados e investigados quanto ao seu comportamento térmico. Os sais se formaram na estequiometria 2:1 (ligante:metal), apresentando águas de hidratação em número característico e foram estáveis até 190- 200 °C. Finalmente foram estudados os mecanismos de decomposição térmica do inosinato-monofosfato de sódio e do guanilato-monofosfato de sódio, dois nucleotídeos que apresentam a propriedade de realçar o sabor de alimentos. Ambos apresentaram elevado grau de hidratação, para o qual foi possível distinguir mecanismos característicos de desidratação. A decomposição dos sais anidros ocorreu com saída do grupo purínico, seguida da decomposição do restante da molécula e formação de pirofosfato de sódio como resíduo final.
Thermal analytical studies of some food addictives of the flavor enhancer class were developed in order to evaluate their stability and resistance to the hot cooking process, as well as to identify the intermediaries of thermal decomposition that could remain at the end of such processes. The salts were obtained from industrial sources or synthesized and characterized by elemental analysis, infra-red spectroscopy, thermogravimetry/derivative thermogravimetry, differential thermal analysis and in some opportunities to differential scanning calorimetry. The glutamic acid and its ammonium, lithium and sodium salts mono and disubstituted were investigated. In all cases a conversion to pyroglutamate has been observed in the free acid and its monosubstituted salts after dehydration. The conversion undergoes by the ?-carboxyl group. The thermal stability was observed to be as high as 190-200 °C. In the case of the lithiu m and sodium dissubstituted salts any conversions to pyroglutamates were observed, once both carboxyl groups were salified. Magnesium, calcium, strontium and barium glutamates has also been synthesized and investigated in relation to its thermal behavior. The salts were formed in the 2:1 stoichiometry (ligand:metal), presenting hydration waters in a characteristic content and showed to be stable up to 190-200 °C. Finally the thermal decomposition mechanisms of dissodium inosinatemonophosphate and dissodium guanilate-monophosphate two nucleotides with flavor enhancement properties in food were also investigated. Both presented high degree of hydration, to which it was possible to propose a water release mechanism. The decomposition of the anhydrous salts occurred with release of the purine group followed by the decomposition of the rest of the molecule generating sodium pyrophosphate as residue.
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9

Laurenti, Karen Cristina. "Avaliação da presença de gordura em tecido muscular e carnes usando DTA e TG." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-14022008-105743/.

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Um dos principais fatores da qualidade de vida está relacionado a uma alimentação saudável. Uma alimentação saudável deve ser composta de uma série de nutrientes que sejam essenciais para o crescimento e para a manutenção dos tecidos e órgãos. Assim, este trabalho tem por objetivo avaliar a presença de gordura intramuscular empregando-se a termogravimetria (TG) e análise térmica diferencial (DTA). Os testes preliminares por TG e DTA foram realizados em músculos de coelho, porco, frango, peixe e boi e suas respectivas gorduras. Realizaram-se experimentos com ratas, submetidas a uma dieta enriquecida com 20% de gorduras (grupo experimental) e dieta com 3,85% de gordura (grupo controle) e verificou-se por análises clínicas do sangue (grupo experimental: colesterol 77,75 \'+ OU -\' 5,90 e triglicérides 110,25 \'+ OU -\' 29,95 e grupo controle: 69,43 \'+ OU -\' 10,40 e triglicérides 103,71 \'+ OU -\' 54,96), poder calorífico do músculo quadríceps (grupo experimental 5615,2 \'+ OU -\' 576,60 e grupo controle 5367 \'+ OU -\' 190,15) e análise térmica diferencial que não houve alterações devido à dieta experimental. Na terceira etapa deste trabalho, utilizaram-se amostras de músculo de boi vastus medialis e gordura bovina pura do músculo (vastus medialis) empregando-se testes termogravimétricos. Na quarta etapa, compararam-se músculos de boi, porco e frango. A termogravimetria (TG) permitiu diferenciar e quantificar as regiões de perda de água, decomposição de colágeno e decomposição da gordura em músculos. Os eventos de perda de água, degradação do colágeno e decomposição da gordura apresentaram-se entre 26 e 200 ºC, 200 e 390 ºC e 400 e 480 ºC respectivamente. Conclui-se que os diferentes tipos de músculos apresentaram comportamento térmico semelhantes, porém, por esta metodologia não foi possível observar a gordura intramuscular.
One of the key factors associated to life quality is related to healthy alimentation. Well balanced and healthy nourishment should be made up of a series of nutrients essential to growth and sustenance of tissues and organs. Thus, the objective of the present work is to assess the presence of intramuscular fat by means of Thermogravimetry (TG) and Differential Thermal Analysis (DTA). The preliminary tests by TG and DTA were performed in the muscles of rabbits, pigs, chickens, fish and cows and their respective fat contents. Experiments were carried out on rats subjected to a diet enriched with 20% fat (experimental group) and a diet with 3,85% fat (control group) and was verified by clinical blood analyses (experimental group: cholesterol 77,75 \'+ OU -\' 5,90 and triglyceride 110,25 \'+ OU -\' 29,95 and the control group: cholesterol 69,43 \'+ OU -\' 10,40 and triglyceride 103,71 \'+ OU -\' 54,96) the calorific value of quadriceps muscles (5615,2 \'+ OU -\' 576,60 for experimental group and 5367 \'+ OU -\' 190,15 for control group) and by differential thermal analysis that there was no alterations due to the experimental diet. The third phase of this study used samples of cow muscle vastus medialis and pure bovine fat from the muscle (vastus medialis) applying thermogravimetric tests. The fourth phase compared cow, pig and chicken muscles. Thermogravimetry (TG) enabled to differentiate and quantify the regions of water loss, collagen decomposition and fat decomposition in muscles. The events of water loss, collagen degradation and fat decomposition are at 26 and 200 ºC, 200 and 390 ºC and at 400 and 480 ºC, respectively. It was concluded that the different types of muscles presented similar thermal behavior; therefore, by this methodology it was not possible to observe intramuscular fat.
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10

Dores, Sebastião Cândido das [UNESP]. "Estudo de processos de cristalização em vidros TW preparados em atmosfera rica em O2." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/143812.

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O objetivo deste trabalho foi estudar os processos de cristalização em vidro 80TeO2-20WO3 preparados em atmosfera ambiente e rica em O2. Os vidros obtidos foram pulverizados em diferentes tamanhos de partículas. Para o estudo de cristalização, medidas de análise térmica diferencial (DTA) foram realizadas em diferentes taxas de aquecimento. Dados complementares de difração de raios-X (DRX) e de espectroscopia Raman foram obtidos com amostras submetidas a diferentes tratamentos térmicos, variando-se ora a temperatura ora o tempo. Dos dados de DTA foi possível determinar as temperaturas de transição vítrea e de cristalização, assim como observar a formação de três fases cristalinas, identificadas como -TeO2, -TeO2 e do WO3 através dos dados de DRX e de Raman. Foi possível observar uma resposta térmica diferente entre as amostras preparadas nas atmosfera ambiente e rica em O2. Os vidros preparados em atmosfera ambiente apresentam na média uma maior estabilidade térmica quando comparada com aquela dos preparados em O2. A energia de ativação associada a cada fase observada foi determinada usando o método de Kissinger e, pelos modelos JMAK e Matusita, foi possível concluir que o processo de cristalização ocorreu preferencialmente na superfície e no volume.
The purpose of this work was to investigate the crystallization processes in 80TeO2-20WO3 glass prepared in ambient and oxygen atmospheres. The obtained glasses were powdered in different grain sizes. For the crystallization study, differential thermal analysis measurements were performed at different heating rates. Additional data from X-ray diffraction and Raman spectroscopy were obtained with samples submitted to different thermal treatments, either by varying the temperature either time. From differential thermal analysis data, it was possible to determine the glass transition and crystallization temperatures, and to observe three crystallization processes, which were identified from X-ray diffraction and Raman data as belonging to the -TeO2, -TeO2, and WO3 phases. It was possible to observe a different thermal response of the samples prepared in ambient atmosphere and rich in O2. The glasses prepared in ambient atmosphere present in average a higher thermal stability when compared with those prepared in O2 atmosphere. The activation energy associated with each observed phase, was determined using the Kissinger method, and by using the JMAK and Matusita models it was concluded that the crystallization process occurred preferentially on the surface and volume.
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Dores, Sebastião Cândido das. "Estudo de processos de cristalização em vidros TW preparados em atmosfera rica em O2 /." Ilha Solteira, 2016. http://hdl.handle.net/11449/143812.

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Orientador: João Carlos Silos Moraes
Resumo: O objetivo deste trabalho foi estudar os processos de cristalização em vidro 80TeO2-20WO3 preparados em atmosfera ambiente e rica em O2. Os vidros obtidos foram pulverizados em diferentes tamanhos de partículas. Para o estudo de cristalização, medidas de análise térmica diferencial (DTA) foram realizadas em diferentes taxas de aquecimento. Dados complementares de difração de raios-X (DRX) e de espectroscopia Raman foram obtidos com amostras submetidas a diferentes tratamentos térmicos, variando-se ora a temperatura ora o tempo. Dos dados de DTA foi possível determinar as temperaturas de transição vítrea e de cristalização, assim como observar a formação de três fases cristalinas, identificadas como -TeO2, -TeO2 e do WO3 através dos dados de DRX e de Raman. Foi possível observar uma resposta térmica diferente entre as amostras preparadas nas atmosfera ambiente e rica em O2. Os vidros preparados em atmosfera ambiente apresentam na média uma maior estabilidade térmica quando comparada com aquela dos preparados em O2. A energia de ativação associada a cada fase observada foi determinada usando o método de Kissinger e, pelos modelos JMAK e Matusita, foi possível concluir que o processo de cristalização ocorreu preferencialmente na superfície e no volume.
Abstract: The purpose of this work was to investigate the crystallization processes in 80TeO2-20WO3 glass prepared in ambient and oxygen atmospheres. The obtained glasses were powdered in different grain sizes. For the crystallization study, differential thermal analysis measurements were performed at different heating rates. Additional data from X-ray diffraction and Raman spectroscopy were obtained with samples submitted to different thermal treatments, either by varying the temperature either time. From differential thermal analysis data, it was possible to determine the glass transition and crystallization temperatures, and to observe three crystallization processes, which were identified from X-ray diffraction and Raman data as belonging to the -TeO2, -TeO2, and WO3 phases. It was possible to observe a different thermal response of the samples prepared in ambient atmosphere and rich in O2. The glasses prepared in ambient atmosphere present in average a higher thermal stability when compared with those prepared in O2 atmosphere. The activation energy associated with each observed phase, was determined using the Kissinger method, and by using the JMAK and Matusita models it was concluded that the crystallization process occurred preferentially on the surface and volume.
Mestre
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12

Chaushli, Azad. "Beiträge zur Darstellung ternärer Nitridometallate von Übergangsmetallen und Reihenuntersuchungen zur Reaktivität entsprechender Eduktgemenge mittels DTA-TG." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=96174507X.

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13

Drapeau, Joanie. "Approche neuropsychologique de la reconnaissance d'émotions dans la démence de type Alzheimer (DTA) en début d'évolution." Mémoire, Université de Sherbrooke, 2009. http://savoirs.usherbrooke.ca/handle/11143/181.

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Persons with dementia of the Alzheimer type (DAT) are impaired in the emotion recognition from face and voice. Yet, clinical practices encourage the use of facial expressions and prosody to communicate with DAT persons. In addition, music, via music therapy, is also used in clinical practices. However, little is known about emotional processing of music in DAT. The goal of the present study is to assess emotion recognition from face, voice and music, in mild DAT and in normal ageing. Method: Ten participants with mild DAT and eleven healthy elderly controls were administered four tasks of emotion recognition from face, voice (prosody) and music. Results: Recognition of sadness and anger from face was impaired for DAT participants as compared to healthy elderly controls, whereas emotional recognition from music was preserved in both groups. Emotional recognition from voice remains however still ambiguous because of methodological limitations which we will try to explain. Conclusions: These results suggest that emotional recognition from music is preserved in mild DAT, which supports the use of the music therapy in clinical practices.
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Pires, Sílvia Magalhães da Silva. "Estudo comparativo da resistência à compressão do betão em provetes normalizados e em estrutura betonada." Master's thesis, Faculdade de Ciências e Tecnologia, 2011. http://hdl.handle.net/10362/6873.

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Dissertação para obtenção do Grau de Mestre em Engenharia dos Materiais
A resistência à compressão é por excelência o parâmetro de caracterização do betão uma estrutura. O presente trabalho consiste no estudo da relação existente entre a resistência à compressão duma estrutura in situ com a resistência à compressão obtida através de ensaios normalizados em laboratório. Para o efeito, procurou-se correlacionar valores obtidos nos ensaios de resistência à compressão (destrutivo) e de esclerometria (não destrutivo) do betão, com o intuito de definir a fiabilidade deste último. Através dos resultados obtidos em ensaios esclerométricos e de resistência à compressão realizados em provetes cúbicos de 150𝑚𝑚 × 150𝑚𝑚 × 150𝑚𝑚 foram traçadas curvas de correlação para dois esclerómetros. Estas curvas relacionam ambos os métodos e serviram de base para a transformação de resultados obtidos em ensaios esclerométricos efectuados directamente na estrutura. Esses resultados foram comparados com ensaios esclerométricos e de resistência à compressão normalizados a que foram submetidos provetes cúbicos moldados com o betão utilizado na estrutura, e ainda com carotes extraídas da mesma. Foram estudadas duas diferentes classes de betão: C25/30 e C30/37 (com e sem adição de cinza volante). Os ensaios foram efectuados nas idades de 3, 7, 14, 28, 56 e 90 dias, tendo sido considerados dois tipos de cura (em condições normalizadas e em condições ambientais). Através de técnicas de caracterização de materiais, nomeadamente FRX, DRX, SEM e DTA/TG procurou-se, ainda, fazer um acompanhamento da evolução da microestrutura durante o processo de hidratação e endurecimento do betão. Para tal, foram moldados prismas de 40𝑚𝑚 × 40𝑚𝑚 × 160𝑚𝑚 de pasta de cimento obtida por peneiração de material proveniente de colheitas de betão utilizadas na execução dos provetes cúbicos. A caracterização microestrutural mostrou a presença de calcite (𝐶 ¯ 𝐶), etringite (𝐶6𝐴¯ 𝑆3𝐻32), monosulfoaluminato (𝐶4𝐴¯ 𝑆𝐻12), portlandite (𝐶𝐻) e silicato de cálcio hidratado (C-S-H ). O ensaio esclerométrico revelou ser válido para a estimativa da resistência do betão na estrutura, desde que sejam traçadas as devidas curvas de correlação para o aparelho tendo em conta os vários factores que influenciam ambos os tipos de ensaio.
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Pereira, Thereza Mylene de Moura. "Caracteriza??o t?rmica (TG/DTG, DTA, DSC, DSC-fotovisual) de Horm?nios bioid?nticos (estriol estradiol)." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13478.

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Bioidentical hormones are defined as compounds that have exactly the same chemical and molecular structure as hormones that are produced in the human body. It is believed that the use of hormones may be safer and more effective than the non-bioidentical hormones, because binding to receptors in the organism would be similar to the endogenous hormone. Bioidentical estrogens have been used in menopausal women, as an alternative to traditional hormone replacement therapy. Thermal data of these hormones are scarce in literature. Thermal analysis comprises a group of techniques that allows evaluating the physical-chemistry properties of a drug, while the drug is subjected to a controlled temperature programming. The thermal techniques are used in pharmaceutical studies for characterization of drugs, purity determination, polymorphism identification, compatibility and evaluation of stability. This study aims to characterize the bioidentical hormones estradiol and estriol through thermal techniques TG/DTG, DTA, DSC, DSC-photovisual. By the TG curves analysis was possible to calculated kinetic parameters for the samples. The kinetic data showed that there is good correlation in the different models used. For both estradiol and estriol, was found zero order reaction, which enabled the construction of the vapor pressure curves. Data from DTA and DSC curves of melting point and purity are the same of literature, showed relation with DSC-photovisual results. The analysis DTA curves showed the fusion event had the best linearity for both hormones. In the evaluation of possible degradation products, the analysis of the infrared shows no degradation products in the solid state
Horm?nios bioid?nticos s?o compostos que t?m exatamente a mesma estrutura qu?mica e molecular dos horm?nios end?genos humanos. Acredita-se que a utiliza??o desses horm?nios pode ser mais segura e eficaz que os horm?nios n?o-bioid?nticos, pois a liga??o aos receptores no organismo se daria de forma semelhante aos horm?nios end?genos. Estrog?nios bioid?nticos v?m sendo utilizado, em mulheres na menopausa, como uma alternativa ? terapia de reposi??o hormonal tradicional. Dados t?rmicos desses horm?nios s?o escassos na literatura. A an?lise t?rmica ? um conjunto de t?cnicas que possibilita medir as propriedades f?sico-qu?micas de uma subst?ncia em fun??o da temperatura. As t?cnicas t?rmicas v?m sendo utilizadas na ?rea farmac?utica em diversas aplica??es, como na caracteriza??o de f?rmacos, determina??o do grau de pureza, identifica??o de polimorfismo, estudos de estabilidade e compatibilidade. Este trabalho tem como objetivo a caracteriza??o dos horm?nios bioid?nticos estradiol e estriol atrav?s das t?cnicas t?rmicas TG/DTG, DTA, DSC, DSC-fotovisual. A partir da an?lise das curvas TG, foi poss?vel calcular os par?metros cin?ticos para as amostras. Os dados cin?ticos mostraram boa correla??o entre os diferentes modelos empregados. Tanto para o estradiol como para o estriol, foi encontrada ordem zero de rea??o, o que possibilitou a constru??o das curvas de press?o de vapor. Dados das curvas DSC e DTA sobre ponto de fus?o e pureza s?o condizentes com a literatura, sendo poss?vel correlacionar estes resultados com o DSC-fotovisual. As an?lises das curvas DTA mostraram o evento de fus?o como o de melhor linearidade para os dois horm?nios. Na avalia??o dos poss?veis produtos de degrada??o, a an?lise do infravermelho mostra que n?o houve produtos de degrada??o no estado s?lido
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Dulina, I. O., T. F. Lobunets, L. O. Klochkov, and A. V. Ragulya. "Synthesis of Ni/NiO Nanosize Powders with Different Phase Ratio by Thermal Decomposition of Nickel Acetate Amines." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35125.

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Ni/NiO nanopowders with different phase ratio have been prepared using thermal decomposition of nickel acetate ammine complexes containing various ammonia content in air at the temperature range 300 – 500 °C. Obtained powders have been characterized by IR-spectroscopy, XRD and TG, DTA, DTG, TEM, laser granulometry and adsorption-structural method. Thermal decomposition of nickel ammine complexes occurred with forming nickel hydroxide, carbonate and hydroxocarbonate ammines precursors. Composition of the precursors depended on temperature and ammonia content in initial complex. Mean crystallite size of nickel depended on temperature only. In the temperature range from 350 to 500 °C the crystallite size of nickel has grown from 50 to 55 nm. Mean crystallite size of nickel oxide depended on temperature and ammonia content. In the temperature range from 350 to 500 °C the crystallite size of NiO has grown from 5 to 25 nm. Increasing ammonia content from 3.6 to 14.4 mol/mol Ni led to decreasing NiO crystallite size from 8 – 10 to 5 nm. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35125
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Suthagar, J., and Kissinger J. K. Suthan. "Synthesis and Characterization of ZnSe1-xTex Alloy Thin Films Deposited by Electron Beam Technique." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/35012.

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ZnSe1-x Tex solid solutions were prepared and films were deposited on glass substrates with x 0.2, 0.4, 0.6 and 0.8. DTA/TGA analysis was carried out to study the alloy formation temperature. Structural studies by XRD results showed the polycrystalline nature of the films. The Full Width at Half Maximum (FWHM) values were observed from the XRD pattern and used to evaluate the microstructural parameters like crystallite size, strain, dislocation density and stacking fault density for all the films with x 0.2, 0.4, 0.6 and 0.8. These films were coated with a thickness of about 200 nm on glass substrates keeping the temperature constant at 200 C. All films showed cubic structure and the lattice parameter values are found to vary with „X‟. This confirms the solid solution formation between the ZnSe and ZnTe binary compounds which are found to obey Vegard‟s law. SEM and AFM studies have been arried out to observe their surface modification with solid solution formation. Raman studies confirm the formation of ZnSe1-xTex compound films. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35012
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18

Mineo, Patrick M. "The Effects of Cold Acclimation on the Thermogenic Capacity of Skeletal Muscle in Mice Deficient in Brown Adipose Tissue." Miami University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=miami1271689398.

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19

Taniwaki, Fábio. "Elaboração de texto básico para capacitação em boas práticas de manipuladores de alimentos." Botucatu, 2019. http://hdl.handle.net/11449/183617.

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Orientador: José Rafael Modolo
Resumo: O número de doenças de origem alimentar, para a saúde pública, o bem-estar e a economia, tem sido frequentemente subestimado devido à subnotificação, a falta de treinamento em diagnosticar as doenças e a dificuldade de se estabelecer relações causais entre a contaminação dos alimentos que poderão resultar em doença ou morte. Grande parte dos casos de doenças transmitidas por alimentos são causados por preparos inadequados no serviço de alimentação, em estabelecimentos ou em mercados. O manipulador é a principal via de contaminação dos alimentos e desempenha um papel importante na segurança e na preservação da higiene dos alimentos durante toda a cadeia produtiva. Portanto, a manipulação incorreta e a negligência em relação às normas higiênicas favorecem a contaminação dos alimentos. O processo de capacitação dos manipuladores deve ser contínuo, a fim de facilitar a implantação dos procedimentos de boas práticas de manipulação, que auxiliam na manutenção da qualidade das refeições produzidas. Assim, a produção alimentar estará livre de microrganismos patogênicos, resultando em alimentos seguros para o consumo humano. Foi elaborado um texto com linguagem didática e ilustrativa, além de uma versão técnica, para a capacitação em boas práticas de manipuladores de alimentos em estabelecimentos. Este trabalho busca contribuir para a capacitação desses profissionais, trazendo resultados positivos para a saúde pública, satisfação e segurança higiênico-sanitária para os consumidores e ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The number of foodborne diseases, for public health, wellness and the economy, has often been underestimated due to underreporting, lack of training in diagnosing diseases and the difficulty in establishing causality regarding food contamination that could result in illness or death. A large share of cases of foodborne diseases are caused by improper preparation in food service, food establishments or markets. Food handlers are the main source of food contamination and they play an important role in achieving food safety and maintaining food hygiene throughout the food production chain. Thus, improper food handling and the neglect of hygienic norms favor food contamination. Food handlers’ training must be continuous to facilitate the implementation of good food handling practices, which help maintain the quality of the food produced. This will result in food production free of pathogenic microorganisms and, as such, safe for human consumption. A didactic and illustrative text was prepared, and also a technical version, to help train food handlers in good food handling practices. This text aims to contribute to the training of these professionals, bringing positive results to public health, satisfaction and hygienic-sanitary safety to consumers and profits to the small business entrepreneur.
Mestre
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20

Prandel, Luis Valério. "INTEGRAÇÃO DE MÉTODOS DE CARACTERIZAÇÃO MINERALÓGICA DE SOLOS CAULINITÍCOS." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2015. http://tede2.uepg.br/jspui/handle/prefix/845.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The soil is a complex and heterogeneous medium containing solid, liquid, gases and several organisms. Its solid phase is composed of minerals that present well defined and highly organized chemical composition. Tropical climate soils, classified as hardsetting, are kaolinitic and present low nutrient and organic matter amounts. Nowadays, there is no consensus about these soils hardsetting characteristics. The characterization of physical and chemical properties of these horizons and their granulometric fractions enables the physical, chemical and mineralogical investigation of five hardsetting soils in this study. Spectroscopic and microscopic techniques, thermal analysis and X-ray diffraction with the Rietveld Method were employed. The RM-XRD made possible to quantify and estimate crystallite average size and mineral micro-deformations. Part of these results was associated to Kaolinite, Halloysite, and Goethite isomorphic substitution. The quantitative XRF analyses revealed the content of chemical elements in the soils under study with higher accuracy. The thermal analysis techniques showed that Kaolinite of weathered soils is susceptible to dehydroxylation at lower temperatures. SEM micrographs revealed the particle typical shapes and these results were confirmed through the AFM that estimated the number of crystallites and the average number of kaolinite layers in the clay fraction. Most of the particles observed through microscopic techniques were ascribed to the Kaolinite, and their micromorphological characteristics could be compared to crystallite size and microdeformations obtained through the RM-XRD. Therefore, based on the results of spectroscopic, microscopic, thermal analyses and X-ray diffraction with Rietveld Method, it was possible to understand the several degrees of crystallinity of minerals which are part of the granulometric fractions of hardsetting horizons in kaolinitic soils.
O solo é um meio complexo e heterogênio de sólidos, líquidos, gases e diversos organismos. A fase sólida é composta de minerais que apresentam composição química definida e altamente ordenada. Solos de clima tropical, classificados como coesos são cauliníticos e apresentam baixa quantidade de nutrientes e matéria orgânica. Atualmente não se chegou a um consenso sobre o caráter coeso desses solos. A caracterização das propriedades físicas e químicas desses horizontes e de suas frações granulométricas possibilita uma investigação física, química e mineralógica de cinco solos coesos de estudo desse trabalho. Para isso foram utilizadas técnicas espectroscópicas, microscópicas, de análises térmicas e Difração de raios X com método de Rietveld. Com os resultados de MR-DRX foi possível quantificar, estimar o tamanho médio de cristalitos e microdeformações dos minerais. Parte desses resultados foram associados com a substituição isomórfica na Caulinita, Haloisita e Goethita. As análises de FRX quantitativas revelaram maior acurácia o teor de elementos químicos nos solos estudados. As técnicas de análises térmicas mostraram que as Caulinitas de solos intemperizados são susceptíveis a desidroxilação a menores temperaturas. Micrografias por MEV revelaram os formatos típicos de partículas e esses resultados foram confirmados por meio da AFM que estimou a quantidade de cristalitos e o número médio de empilhamento das camadas de Caulinita na fração argila. A maior parte das partículas observadas nas técnicas microscópicas foi atribuída a Caulinita, sendo que suas características micromorfológicas puderam ser comparadas com tamanho de cristalitos e microdeformações obtidos pelo MRDRX. Assim, com base nos resultados das análises espectroscópicas, microscópicas, térmicas e de difração de raios X pelo método de Rietveld foi possível compreender os diversos graus de cristalinidade dos minerais que compõem as frações granulométricas de horizontes coesos de solos cauliníticos.
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21

Masberg, Stefan. "Differentialkalorimetrie (DSC) und Differentialthermoanalyse (DTA) bei hohen Drücken Untersuchungen zum Phasenverhalten ausgewählter Triacylglycerine, Flüssigkristalle und Anthrachinonfarbstoffe bis 200 MPa /." [S.l. : s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=959480935.

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22

Gély-Nargeot, Marie-Christine. "Hétérogénéité des manifestations neuropsychologiques précoces dans les démences de type Alzheimer (DTA) : étude des processus mnésiques avec suivi longitudinal." Montpellier 1, 1991. http://www.theses.fr/1991MON11249.

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23

Kadok, Joris. "Le système binaire aluminium-iridium, du diagramme de phases aux surfaces atomiques." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0202/document.

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Un alliage métallique complexe (CMA) est un composé intermétallique dont la maille élémentaire est constituée d’un nombre important d’atomes formant bien souvent des aggrégats de haute symmétrie. De la complexité de ces composés peuvent découler des propriétés physico-chimiques intéressantes pour divers domaines d’application. Le système binaire aluminium-iridium est un système qui présente de nombreux composés intermétalliques dont la moitié sont des CMA. Malgré l’étude approfondie dont ce système a fait l’objet dans la littérature, certaines incertitudes demeuraient irrésolues, nous amenant ainsi à réexaminer le diagramme de phase Al-Ir. Nous avons également exploré les systèmes ternaires dits "push-pull" Al-Au-Ir et Al-Ag-Ir, propices à la formation de phases CMA selon certains auteurs. Au total, une centaine d’échantillons ont été préparés par fusion à l’arc puis analysés par diverses techniques de caractérisations: diffraction des rayons X (XRD), microscopie électronique à balayage (SEM), analyse dispersive en énergie (EDS) et analyse thermique différentielle (DTA). Quatre nouveaux composés intermétalliques ont ainsi été identifiés: Al2.4Ir, Al72Au2.5Ir29.5, Al3AuIr et Al11SiIr6, ce dernier étant issu d’une manipulation accidentelle. La structure cristallographique de chacun de ces composés a été résolue, révélant Al2.4Ir et Al72Au2.5Ir29.5 comme étant des CMA possédant une centaine d’atomes dans la maille. Des calculs basés sur la théorie de la fonctionnelle de la densité (DFT) sont venus apporter des précisions concernant la stabilité des composés Al3AuIr et Al11SiIr6. Pour le système Al-Ir, une variante structurale de deux CMA déjà connus de la littérature a également pu être mise en évidence. Les structures cristallographiques de la variante de Al2.75Ir et de celle de Al28Ir9 ont ainsi été approchées, présentant 240 et 444 atomes dans leur maille respective. Les propriétés de surface comptent parmi les aspects les plus intéressants des CMA, par exemple pour la catalyse hétérogène. En l’absence de monocristaux de taille macroscopique, nous avons étudié la possibilité de former des composés de surface par dépôt de Ir sur une surface Al(100) suivi de recuits. Des caractérisations par diffraction d’électrons lents (LEED), spectroscopie de photoélectrons excités par rayons X (XPS) et microscopie à effet tunnel (STM) supportés par ces calculs ab initio ont révélé qu’à partir de 320°C, le composé Al9Ir2 se formait en surface mais également dans une partie du volume du substrat
A complex metallic alloy (CMA) is an intermetallic compound whose unit cell contains a large number of atoms oftenly forming highly-symmetric clusters. From the complexity of these compounds can arise physical and chemical properties interesting for various fields of application. The aluminium-iridium binary system exhibits numerous intermetallic compounds of which half of them are actually CMAs. Despite this system being extensively studied in the literature, some uncertainies remained unsolved, leading us to reinvestigate the Al-Ir phase diagram. In addition, the "push-pull" systems Al-Au-Ir and Al-Ag-Ir, favorable for the formation of CMA according to the literature, have been explored. Thus, near a hundred of samples have been prepared by arc-melting before being analyzed with different characterizations techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and differential thermal analysis (DTA). From this study, 4 new intermetallic compounds could be identified: Al2.4Ir, Al72Au2.5Ir29.5, Al3AuIr and Al11SiIr6, the latter being the result of a fortuitous manipulation. The crystallographic structure of each of these compounds has been solved, revealing Al2.4Ir and Al72Au2.5Ir29.5 to be two CMAs with around one hundred of atoms in their unit cell. Calculations based on the density functional theory (DFT) brought further details about the stability of the two other Al3AuIr and Al11SiIr6 compounds. In the Al-Ir binary system, a structural variant of two well-known CMAs has been also unveiled. The crystallographic structures of the Al2.75Ir and Al28Ir9 variant have been approached, revealing 240 and 444 atoms in their respective unit cell. The CMAs oftently exhibit interesting surface properties. In order to study the Al-Ir compound surfaces, iridium adsorption on Al(100) surface followed by annealing has been investigated. The characterizations by lowenergy electrons diffraction (LEED), X-ray photoelectron spectroscopy (XPS) and scanning tunneling miscoscopy (STM) supported by ab initio calculations revealed that, from 320 C, the Al9Ir2 compound is formed at the surface but also in the substrate bulk
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Carmo, Ana Carolina Paiva. "Investiga??o da estabilidade t?rmica e das propriedades el?tricas do TiO2 em fun??o da dopagem com Ce(SO4)2." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17588.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
The metalic oxides have been studies due to differents applications as materials semiconductor in solar cells, catalysts, full cells and, resistors. Titanium dioxide (TiO2) has a high electric conductivity due to oxygen vacancies. The Ce(SO4)2.2H2O doped samples TiO2 and TiO2 pure was obtained sol-gel process, and characterized by X-ray diffractometry,thermal analysis, and impedance spectroscopy. The X-ray diffraction patterns for TiO2 pure samples shows at 700?C anatase phase is absent, and only the diffraction peaks of rutile phase are observed. However, the cerium doped samples only at 900?C rutile in the phase present with peaks of cerium dioxide (CeO2). The thermal analysis of the TiO2 pure and small concentration cerium doped samples show two steps weight loss corresponding to water of hydration and chemisorbed. To larger concentration cerium doped samples were observed two steps weight loss in the transformation of the doped cerium possible intermediate species and SO3. Finally, two steps weight loss the end products CeO2 and SO3 are formed. Analyse electric properties at different temperatures and concentration cerium doped samples have been investigated by impedance spectroscopy. It was observed that titanium, can be substituted by cerium, changing its electric properties, and increased thermal stability of TiO2 anatase structure
Os ?xidos met?licos t?m sido muito estudados devido suas diversas aplica??es como materiais semicondutores em c?lulas solares, catalisadores, c?lulas combust?veis e resistores. O Di?xido de Tit?nio possui uma alta condutividade el?trica devido ?s suas vac?ncias de oxig?nio. Amostras de TiO2 puro, obtidas pelo m?todo sol-gel e dopadas com solu??es de Ce(SO4)2.2H2O, foram analisadas atrav?s de difratometria de raios-X, an?lise t?rmica e espectroscopia de imped?ncia. Atrav?s dos difratogramas de raios-X observou-se a transi??o completa das fases anat?sio-rutilo, para a amostra do TiO2 puro a partir de 700?C. Entretanto, para as amostras dopadas, essa transi??o s? ? completa a partir de 900?C, aparecendo picos correspondentes ao ?xido de c?rio. Atrav?s da an?lise t?rmica se observou uma perda de massa, para o TiO2 puro e dopado com a menor concentra??o de c?rio, correspondente ? desidrata??o e a ?gua quimissorvida. Para as amostras dopadas em uma maior concentra??o, foram observados dois est?gios de perda de massa, devido a decomposi??o do dopante em intermedi?rios e SO3. Essas amostras apresentaram mais duas perdas de massa devido a forma??o do CeO2 e SO3. A partir da espectroscopia de imped?ncia analisou-se as propriedades el?tricas das amostras em fun??o da temperatura de calcina??o e em fun??o da concentra??o do dopante. Tamb?m foi observado que o c?rio, por ter a capacidade de substituir o tit?nio na sua estrutura cristalina, modifica suas propriedades el?tricas e tem o poder de estabiliz?-lo termicamente em certas temperaturas
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Neher, Roland. "Phasenbeziehungen und kinetische Modellierung von flüssigphasengesintertem SiC mit oxidischen und nitridischen Additiven." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-148121.

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In the present dissertation the formation of microstructure, the kinetics of densification and the formation of surface layers developing during liquid phase sintering of silicon carbide are studied. The focus is on the additive systems Al2O3 plus Y2O3 and AlN plus Y2O3. Phase and especially liquid phase formation in both of the systems SiC, Al2O3 , Y2O3 and AlN, Al2O3 , Y2O3 are investigated in detail examining 12 espectively 17 different compositions per system. Melting temperatures have been determined by TG/DTA, in both systems for the first time. Phase composition of samples was analysed by the combination of XRD, SEM and EDX. In the system SiC, Al2O3 , Y2O3 the formation of the phases expected from the quasibinary Al2O3 , Y2O3 could be observed thus silicon carbide has to be in equilibrium with the oxide additives. The low solubility of SiC in the oxide melt, which was suggested by Hoffmann and Nader, could be confirmed. In the system AlN, Al2O3 , Y2O3 the formation of phases as stated by Medraj was confirmed, except for the dimension of the stability region of the γ- spinel and YAG which is wider in the present work. For the first time diffusion coefficients of the species Y3+ and Al3+ in the oxide melt formed by Al2O3 and Y2O3 at temperatures above 1825 ◦ C were determined. The values are in the order of 2 · 10−6 cm2 /s which results in a diffusion length of 14.1 μm for a diffusion time of one second. This allows the fast equilibration of Y and Al deficiencies. Kinetics of densification was modeled by kinetic field, master curve and thermokinetic method, based on detailed experimental investigation of the shrinkage during liquid phase sintering of SiC. It could be proved that the first 30 − 40 % of densification are controlled by solid phase reactions which accelerate particle rearrangement without presence of a liquid phase. During the remaining 60 − 70 % of densification a liquid is present, resulting in the predominance of mechanisms of liquid phase sintering. The models deliver activation energies in the range from 608 KJ/mol to 1668 kJ/mol and allow, within the scope of validity of each method the prediction of densification during liquid phase sintering of silicon carbide. When sintering silicon carbide with Al2O3 plus Y2O3 the formation of several surface layers, depending on atmosphere, maximum temperature, dwelling time and amount and composition of additives was observed. In nitrogen atmosphere with low partial pressures a surface layer consisting of AlN is forming whilst at high partial pressures SiAlON- polytypes occur. After sintering in Argon or Ar-CO- atmosphere three main types of surface layers are present. One consists of alumina, one contains only YAG and one shows highly porous, additive depleted regions. An explanation for the formation of the several surface layers could be given by the combination of the determined diffusion coefficients with the results achieved in the thermodynamics part. The results achieved in this work can be a contribution to the knowledge based design of the production process of liquid phase sintering of silicon carbide.
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26

Yahya, Mahzoun. "Heating Value and Energy Recovery Potential of Sewage Sludge and Suspended Solids in Municipal Wastewater Treatment Plant." Kyoto University, 2018. http://hdl.handle.net/2433/232029.

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27

Salameh, Jean-Paul. "Diagnostic Test Accuracy Systematic Reviews: Evaluation of Completeness of Reporting and Elaboration on Optimal Practices." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39443.

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Systematic reviews of diagnostic test accuracy (DTA) studies are fundamental to the decision-making process in evidence-based medicine. Although such studies are regarded as high-level evidence, these reviews are not always reported completely and transparently. Sub-optimal reporting of DTA systematic reviews compromises their validity, generalizability, and value to key stakeholders. This thesis evaluates the completeness of reporting of published DTA systematic reviews based on the PRISMA-DTA checklist and provides an explanation for the new and modified items (relative to PRISMA), along with their meaning and rationale. Our results demonstrate that recently published reports of DTA systematic reviews are not fully informative, when evaluated against the PRISMA-DTA guidelines: mean reported items=18.6/26(71%, SD=1.9) for PRISMA-DTA; 5.5/11(50%, SD=1.2) for PRISMA-DTA for abstracts. The PRISMA-DTA statement, this document, and the associated website (http://www. prisma-statement.org/Extensions/DTA) are meant to be helpful resources to support the transparent reporting of DTA systematic reviews and guide knowledge translation strategies.
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28

Hoffmann, Caroline C. "Investigation into the use of the Vibrio fischeri bioluminescence assay as a direct toxicity assessment (DTA) tool in the activated sludge environment." Thesis, Edinburgh Napier University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326639.

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29

Frühauf, Katja [Verfasser], and Ulrike [Akademischer Betreuer] Gaul. "Dissecting the regulation of gene expression during steroid hormone signaling in Drosophila by Dynamic Transcriptome Analysis (DTA) / Katja Frühauf. Betreuer: Ulrike Gaul." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-192728.

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30

Porto, Dayanne Lopes. "Contribui??es sobre estudos t?rmicos (TG/DTG, DTA, DSC e DSC-Fotovisual) da rifampicina e seus principais produtos de degrada??o." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13506.

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Since its synthesis over 48 years rifampicin has been extensively studied. The literature reports the characterization of thermal events for rifampicin in nitrogen atmosphere, however, no characterization in synthetic air atmosphere. This paper aims to contribute to the thermal study of rifampicin through thermal (TG / DTG, DTA, DSC and DSC - FOTOVISUAL ) and non-thermal (HPLC, XRPD , IR - FTIR , PCA) and its main degradation products ( rifampicin quinone , rifampicin N-oxide 3- formylrifamicin). Rifampicin study was characterized as polymorph form II from techniques DSC, IR and XRPD. TG curves for rifampicin in synthetic air atmosphere showed higher thermal stability than those in N2, when analyzed Ti and Ea. There was characterized as overlapping events melting and recrystallization under N2 with weight loss in the TG curve, suggesting concomitant decomposition. Images DSCFotovisual showed no fusion event and showed darkening of the sample during analysis. The DTA curve in synthetic air atmosphere was visually different from DTA and DSC curves under N2, suggesting the absence of recrystallization and melting or presence only decomposition. The IV - FTIR analysis along with PCA analysis and HPLC and thermal data suggest that rifampicin for their fusion is concomitant decomposition of the sample in N2 and fusion events and recrystallization do not occur in synthetic air atmosphere. Decomposition products studied in an air atmosphere showed no melting event and presented simultaneously to the decomposition initiation of heating after process loss of water and / or solvent, varying the Ti initiating events. The Coats - Redfern , Madsudhanan , Van Krevelen and Herwitz - Mertzger kinetic parameters for samples , through the methods of OZAWA , in an atmosphere of synthetic air and / or N2 rifampicin proved more stable than its degradation products . The kinetic data showed good correlation between the different models employed. In this way we contribute to obtaining information that may assist studies of pharmaceutical compatibility and stability of substances
estudada. H? relatos de estudos focando o desenvolvimento de metodologias anal?ticas, novas aplica??es farmac?uticas, bem como, desenvolvimento de novas formas farmac?uticas. A busca pelo entendimento dascaracter?sticas f?sico-qu?micas das subst?ncias tem auxiliado no desenvolvimento de novos produtos farmac?uticos, com seguran?a, efic?cia e qualidade,fornecendo informa??es ?teis sobre s?ntese e armazenamento. Dentre os produtos de decomposi??o j? conhecidos para rifampicina, temos a rifampicina quinona, rifampicina N-?xido e 3-formilrifampicina, para tais, dados t?rmicos s?o escassos na literatura. As t?cnicas t?rmicas v?m sendo utilizadas na ?rea farmac?utica em diversas aplica??es, como na caracteriza??o de f?rmacos, determina??o do grau de pureza, identifica??o de polimorfismo, estudos de estabilidade, compatibilidade e cin?tica de degrada??o. Este trabalho tem como objetivo contribuir com o estudo t?rmico da rifampicina atrav?s das t?cnicas t?rmicas (TG/DTG, DTA, DSC, DSC-Fotovisual)e n?o t?rmicas, e seus principais produtos de degrada??o (rifampicina quinona, rifampicina N-?xido 3-formilrifamicina). A partir de an?lises DSC, DRX e FTIR foi poss?vel caracterizar a rifampicina estudada como polimorfo II. O conjunto de t?cnicas t?rmicas e n?o t?rmicas auxiliaram a verificar que parte da rifamipicina ? decomposta durante o processo de fus?o, em atmosfera de nitrog?nio, bem como que, os eventos de fus?o e recristaliza??o n?o ocorrem em atmosfera de ar sint?tico passando a amostra diretamente a decomposi??o. Os produtos de decomposi??o estudados, quando em atmosfera de ar, n?o apresentaram evento de fus?o e, apresentaram v?rios passos de decomposi??o, com a ocorr?ncia de eventos exot?rmicos e endot?rmicos. A partir de curvas TG din?micas, foi poss?vel calcular os par?metros cin?ticos para as amostras, atrav?s dos m?todos de OZAWA, Coats-Redfern, Madsudhanan, Van Krevelen e Herwitz-Mertzger, em atmosfera de ar sint?tico e/ou nitrog?nio. Os dados cin?ticos mostraram boa correla??o entre os diferentes modelos empregados. Tanto para rifampicina quanto os produtos de degrada??o estudados, foi caracterizado rea??o de ordem um
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31

Frühauf, Katja Verfasser], and Ulrike [Akademischer Betreuer] [Gaul. "Dissecting the regulation of gene expression during steroid hormone signaling in Drosophila by Dynamic Transcriptome Analysis (DTA) / Katja Frühauf. Betreuer: Ulrike Gaul." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/1094517003/34.

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32

Provencher, Véronique. "Exploration des divers impacts de l'apprentissage de tâches significatives liées à la vie quotidienne dans la démence de type Alzheimer (DTA) en début d'evolution." Mémoire, Université de Sherbrooke, 2006. http://savoirs.usherbrooke.ca/handle/11143/2513.

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Les déficits cognitifs généralement rencontrés dans les phases initiales de la démence de type Alzheimer (DTA) risquent d'amener la personne à éprouver des difficultés à réaliser certaines tâches quotidiennes, susceptibles de mener à l'abandon d'activités significatives de loisirs. De récentes études documentent l'efficacité des méthodes de récupération espacée, d'estompage et sans erreur pour faire apprendre des tâches spécifiques à des personnes atteintes de DTA en début d'évolution. Cependant, l'effet de ces apprentissages sur certains aspects du fonctionnement quotidien demeure peu exploré. Objectifs : Explorer l'effet d'une intervention utilisant ces méthodes sur 1- l'apprentissage de tâches spécifiques et le transfert de ces apprentissages; 2- sur la réalisation spontanée d'une activité de loisirs et sa poursuite dans la vie quotidienne. Méthodologie : Étude à sujet unique réalisée auprès d'une dame atteinte de DTA en début d'évolution (77 ans, MMSE = 24/30). Dispositif : ABA à niveaux de bases multiples par tâches (cible et contrôles). Étude 1 : Écouter de la musique. Intervention : Apprendre la tâche cible et une tâche contrôle avec les méthodes, puis transférer ces apprentissages dans des situations du quotidien. Tâches : utiliser un radiocassette (cible), un vidéocassette (contrôle) et une enregistreuse (contrôle) 2 - Étude 2 : Prier en groupe. Intervention 1 : Apprendre à associer le son d'une alarme à l'heure de la prière avec les méthodes, puis à transférer cet apprentissage dans des situations du quotidien; Intervention 2 : Apprendre la tâche cible et une tâche contrôle avec les méthodes. Tâches : se rendre à la salle de chapelet (cible), de lavage (contrôle) et de jeu de poches (contrôle). Résultats : Étude 1 : Les analyses statistiques révèlent une augmentation significative de la performance (p < 0,001) uniquement pour les tâches apprises avec les méthodes. Les apprentissages relatifs à l'utilisation du radiocassette ont pu être transférés dans une proportion de 58,5%. La participante écoute rarement de la musique pendant (3 fois en 3 mois) et après l'intervention (1 fois en 3 mois). Étude 2 : La participante a appris à utiliser l'alarme en moins de 13 essais. L'apprentissage a pu être transféré dans une proportion de 55,6%. Les analyses statistiques révèlent une augmentation significative de la performance (p < 0,001) pour les trajets appris avec les méthodes. La participante va régulièrement prier en groupe, pendant et après l'intervention (2-3 fois par semaine). Discussion et conclusion : Les méthodes se sont avérées efficaces pour faire apprendre des tâches spécifiques à une personne atteinte de DTA en début d'évolution. Cependant, le transfert de ces apprentissages s'est révélé plus difficile. L'utilisation d'une alarme est apparue probante pour favoriser la réalisation spontanée et la poursuite d'une activité de loisirs. L'intégration dans la routine quotidienne de stratégies environnementales offrant des rappels réguliers pourrait ainsi contribuer à une amélioration de l'autonomie et de la qualité de vie de certaines personnes atteintes de DTA en début d'évolution.
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33

Provencher, Véronique. "Exploration des divers impacts de l'apprentissage de tâches significatives liées à la vie quotidienne dans la démence de type Alzheimer (DTA) en début d'evolution." [S.l. : s.n.], 2006.

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34

Hoyer, Ina Marie. "Beitrag zur Entwicklung von Hochtemperaturloten auf Eisenbasis." Doctoral thesis, Universitätsbibliothek Chemnitz, 2005. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200501475.

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Das Ziel der Dissertation besteht darin, einen Beitrag zur Entwicklung von Hochtemperaturloten auf Eisenbasis mit Liquidustemperaturen von < 1100 °C zu leisten. Die Lote sollen als alternative Werkstoffe für die derzeit verwendeten Nickelbasislote im Werkzeug- und Wärmetauscherbau Anwendung finden. Als Grundwerkstoffe kommen Werkzeugstähle sowie rost- und säurebeständige Stähle in Betracht. Wichtige Legierungselemente sind Silizium, Nickel, Chrom und Bor. Eine Verbesserung gegenüber den Nickelbasisloten soll die Gefügeausbildung in Abhängigkeit der Lötspaltbreite sowie das Korrosionsverhalten darstellen. Entsprechende Ergebnisse werden aufgezeigt und mit Daten zur Zugfestigkeit, zum Zähigkeitsverhalten im Schlagbiegeversuch sowie zur Härteverteilung über die Lötnaht vervollständigt. Für ein Verständnis des Schmelzverhaltens dienen DTA-Untersuchungen. Eine Einordnung der entwickelten Lote in den derzeitigen Stand der Forschung wird gegeben. Weiterführendes Forschungs- und Entwicklungspotenzial wird aufgezeigt.
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35

Schwalb, Björn [Verfasser], and Patrick [Akademischer Betreuer] Cramer. "Dynamic transcriptome analysis (DTA) : kinetic modeling of synthesis and decay of mRNA transcripts upon perturbation in S.cerevisiae, S.pombe and D.melanogaster / Björn Schwalb. Betreuer: Patrick Cramer." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2012. http://d-nb.info/1026211158/34.

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36

林俊豪. "TG-DTA-IR在含揮發性成分中藥制劑質量分析和控制中的應用." HKBU Institutional Repository, 2011. http://repository.hkbu.edu.hk/etd_ra/1329.

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37

Siqueira, Geisa Liandra de Andrade de. "EFEITO DO TRATAMENTO ÁCIDO EM MEIO AQUOSO E ALCOÓLICO NA MODIFICAÇÃO DO AMIDO DE PINHÃO (Araucaria angustifolia)." Universidade Estadual de Ponta Grossa, 2017. http://tede2.uepg.br/jspui/handle/prefix/2667.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Araucaria angustifolia (Bert.) O. Kuntze é uma conífera presente nas florestas brasileiras e as suas sementes apresentam alto teor de amido. Os pinhões utilizados nesta pesquisa foram provenientes de materiais genéticos e selecionados com base em testes preliminares por apresentarem temperatura de gelatinização inferior a 60ºC. Esta é considerada uma característica interessante e vantajosa, podendo economizar tempo e energia durante o processo de gelatinização do amido. O amido na sua forma natural apresenta limitações, portanto uma das alternativas é a hidrólise ácida que tem o intuito de alterar as suas propriedades físico-químicas. Este tratamento aliado a solução alcoólica apresenta a capacidade de recuperar grande parte do grânulo. O objetivo deste estudo foi identificar os efeitos da modificação ácida em meio aquoso e alcoólico de amidos de pinhão (A. angustifolia) com temperaturas de gelatinização abaixo de 60 ºC. As amostras foram avaliadas quanto ao pH e Colorimetria, por análise térmica (TG-DTA e DSC), pelo comportamento reológico (RVA), por análises estruturais (DRX e MEV) e por análises estatísticas (ANOVA e Tukey). A recuperação do grânulo de amido foi maior no meio aquoso e no meio alcoólico os valores ficaram próximos a 90% de recuperação. Os valores de pH comprovaram que o processo eliminou o ácido utilizado na modificação e a colorimetria identificou a coloração branca e levemente amarela para ambos os acessos, mostrando que os tratamentos não alteraram as características colorimétricas dos amidos de pinhão. Nas curvas TGDTA em ar sintético foram observadas três perdas de massa. As amostras nativas apresentaram diferença no DTA e as temperaturas finais demonstraram maior resistência térmica dos amidos. Nas curvas TG-DTA em nitrogênio foram encontradas duas perdas de massa. As amostras tratadas apresentaram semelhança no DTA e as temperaturas finais não foram alteradas devido à atmosfera inerte. Na análise de DSC, a Tc e a ∆Hgel não apresentaram diferenças significativas, apenas no To e Tp. Os tratamentos mais intensos mostraram leve resistência térmica e menor ∆Hgel. No RVA foi observado redução nos parâmetros de viscosidade conforme a intensidade do tratamento. O DRX identificou o padrão do tipo C para os amidos e a cristalinidade relativa aumentou conforme a intensidade da hidrólise ácida. Pelo MEV foram observadas alterações superficiais nos grânulos. Diante dos resultados encontrados, os amidos de pinhão demonstraram ser promissores para aplicações industriais visando specialties, ou seja, para produtos com escala reduzida. O intuito é estimular os pequenos produtores, proporcionar agregação de valor ao produto final e a manutenção da espécie A. angustifolia.
Araucaria angustifolia (Bert.) O. Kuntze is a conifer present in Brazilian forests and its seeds are high in starch. The pinhões used in this research were derived from genetic material and selected based on preliminary tests because they presented a gelatinization temperature below the 60 ºC. This is considered an interesting and advantageous feature, which can save time and energy during the starch gelatinization process. Starch in its natural form has limitations, so one of the alternatives is acid hydrolysis, which has the purpose of altering its physicochemical properties. This treatment combined with alcoholic solution has the ability to recover majority of the granule. The aim of this study was to identify the effects of acidic modification on aqueous and alcoholic solutions of pinhão starches (A. angustifolia) with gelatinization temperatures below of 60 ºC. The samples were evaluated for pH and Colorimetry by thermal analysis (TG-DTA e DSC), by rheological behavior (RVA), by structural analysis (XRD and SEM) and by statistical analysis (ANOVA and Tukey). The recovery of the starch granule was higher in the aqueous medium and in the alcoholic solution; the values were close to 90% recovery. The pH values showed that the process eliminated the acid used in the modification and the Colorimetry identified the white and slightly yellow coloration for both accessions, showing that the treatments did not alter the colorimetric characteristics of the pinhão starches. In the TG-DTA curves in synthetic air, three mass losses were observed. The native samples presented a difference in the DTA and the final temperatures showed a higher thermal resistance of the starches. In the TG-DTA curves in nitrogen, two mass losses were found. The treated samples showed similarity in DTA and the final temperatures were not changed due to the inert atmosphere. In the DSC analysis, Tc and ΔHgel did not show significant differences, only in To and Tp. The most intense treatments showed light thermal resistance and lower ΔHgel. In the RVA, a reduction in the viscosity parameters was observed according to the intensity of the treatment. XRD identified the type C pattern for starches and relative crystallinity increased as the acid hydrolysis rate increased. Superficial changes in the granules were observed by SEM. Considering the results found, the pinhão starches demonstrated to be promising for industrial applications aiming specialties, that is, for products with reduced scale. The intention is to stimulate small producers, provide benefits to the final product and the maintenance of the species A. angustifolia.
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38

Fu, Jingyi J. Y. "Delay Analysis of Digital Circuits Using Prony's Method." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20125.

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This thesis describes possible applications of Prony's method in timing analysis of digital circuits. Such applications include predicting the future shape of the waveform in DTA(Dynamic Timing Analysis) and delay look-up table in STA(Static Timing Analysis). Given some equally spaced output values, the traditional Prony's method can be used to extract poles and residues of a linear system, i.e. to characterize a waveform using an exponential function. In this thesis, not only values but also equally spaced derivatives are tested. Still using same idea of the traditional Prony's method, poles and residues can also be extracted with those values and derivatives. The resultant poles and residues will be used to predict the output waveform in DTA analysis. The benefits brought by the using of derivatives include less simulation steps and less CPU time consuming than the regular constant step simulation. As a matter of fact, the Prony's method can precisely approximate a complicated waveform. Such property can be applied for STA analysis. The Prony's approximation can be used to precisely record an output waveform, which is used as an entry of the look-up table of STA. Since the accuracy of STA analysis relies on the accuracy of the input and output waveform in the look-up table, the accuracy of the Prony's approach is promising.
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39

Råberg, Mathias. "Black liquor gasification : experimental stability studies of smelt components and refractory lining." Doctoral thesis, Umeå University, Energy Technology and Thermal Process Chemistry, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1151.

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Black liquors are presently combusted in recovery boilers where the inorganic cooking chemicals are recovered and the energy in the organic material is converted to steam and electricity. A new technology, developed by Chemrec AB, is black liquor gasification (BLG). BLG has more to offer compared to the recovery boiler process, in terms of on-site generation of electric power, liquid fuel and process chemicals. A prerequisite for both optimization of existing processes and the commercialization of BLG is better understanding of the physical and chemical processes involved including interactions with the refractory lining. The chemistry in the BLG process is very complex and to minimize extensive and expensive time-consuming studies otherwise required accurate and reliable model descriptions are needed for a full understanding of most chemical and physical processes as well as for up-scaling of the new BLG processes. However, by using these calculated model results in practice, the errors in the state of the art thermochemical data have to be considered. An extensive literature review was therefore performed to update the data needed for unary, binary and higher order systems. The results from the review reviled that there is a significant range of uncertainty for several condensed phases and a few gas species. This resulted in experimental re-determinations of the binary phase diagrams sodium carbonate-sodium sulfide (Na2CO3-Na2S) and sodium sulfate-sodium sulfide (Na2SO4-Na2S) using High Temperature Microscopy (HTM), High Temperature X-ray Diffraction (HT-XRD) and Differential Thermal Analysis (DTA). For the Na2CO3-Na2S system, measurements were carried out in dry inert atmosphere at temperatures from 25 to 1200 °C. To examine the influence of pure CO2 atmosphere on the melting behavior, HTM experiments in the same temperature interval were made. The results include re-determination of liquidus curves, in the Na2CO3 rich area, melting points of the pure components as well as determination of the extent of the solid solution, Na2CO3(ss), area. The thermal stability of Na2SO3 was studied and the binary phase diagram Na2SO4-Na2S was re-determined. The results indicate that Na2SO3 can exist for a short time up to 750 °C, before it melts. It was also proved that a solid/solid transformation, not reported earlier, occurs at 675 ± 10 °C. At around 700 °C, Na2SO3 gradually breaks down within a few hours, to finally form the solid phases Na2SO4 and Na2S. From HTM measurements a metastable phase diagram including Na2SO3, as well as an equilibrium phase diagram have been constructed for the binary system Na2SO4-Na2S. Improved data on Na2S was experimentally obtained by using solid-state EMF measurements. The equilibrium constant for Na2S(s) was determined to be log Kf(Na2S(s)) (± 0.05) = 216.28 – 4750(T/K)–1 – 28.28878 ln (T/K). Gibbs energy of formation for Na2S(s) was obtained as ΔfG°(Na2S(s))/(kJ mol–1) (± 1.0) = 90.9 – 4.1407(T/K) + 0.5415849(T/K) ln (T/K). The standard enthalpy of formation of Na2S(s) was evaluated to be ΔfH°(Na2S(s), 298.15 K)/(kJ mol–1) (± 1.0) = – 369.0. The standard entropy was evaluated to be S°(Na2S(s), 298.15 K)/(J mol–1 K–1) (± 2.0) = 97.0. Analyses of used refractory material from the Chemrec gasifier were also performed in order to elucidate the stability of the refractory lining. Scanning electron microscopy (SEM) analysis revealed that the chemical attack was limited to 250-300 μm, of the surface directly exposed to the gasification atmosphere and the smelt. From XRD analysis it was found that the phases in this surface layer of the refractory were dominated by sodiumaluminosilicates, mainly Na1.55Al1.55Si0.45O4.

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40

Bertolazi, Vanessa Thoma. "Concentração de argilominerais 2:1 em solos subtropicais." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/5566.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The 2:1 expandable clay minerals have high importance when present in soil, even in small amount, as in the case of soil with a high degree of secondary alteration. The study of these minerals is essential to understanding the physical and chemical behavior of soils, however, the techniques have not always permitted their suitable concentration, in order to facilitate their study. Therefore, this study aimed to analyze the concentration of phyllosilicates clay minerals with 2:1 structure through the technique of selective dissolution of oxides and kaolinite, aiming their study by X-ray diffraction and thermal analysis. The samples were collected in Rio Grande do Sul, in different weather conditions in profiles of Regosols (RRd and RRe), Ferralsol (LVd) and Vertisol (VEo). The clay fraction of A and B horizons of soil were separated and subjected to treatment with dithionite-citrate-bicarbonate and then with warm NaOH in 10 different concentrations, from 0.5 to 5 mol L-1. For mineralogical characterization we used the techniques of X-ray diffraction (XRD), thermogravimetry (TG) and differential thermal analysis (DTA). The results obtained by the analysis of X-ray diffraction showed that for most weathered soils as the Ferrasol, the NaOH solution does not contribute to the concentration of the 2:1 mineral. However, to the Vertisol the solution of NaOH 4.0 mol L-1 was more efficient in the concentration of minerals. To the Regossol RRd no concentration of NaOH solution was effective and to the RRe the concentration of 2.5 mol L-1 solution of NaOH was most suitable for concentrating the 2:1 clay. The extraction of kaolinite and gibbsite by NaOH solution was only partial for kaolinite. The thermal analysis showed predominance of kaolinite and gibbsite in relation to the 2:1 minerals in the samples free of oxides. The most effective treatment for the thermal analysis for 2:1 mineral concentration was NaOH 4 mol L-1 for samples LVd B, RRh A, RRe A and Veo A. The NaOH 3 mol L-1 treatment was more efficient for samples LVd A and VEo B. The relative concentration of 2:1 was higher in samples with dystrophic character.
Os argilominerais 2:1 expansíveis apresentam elevada importância quando presentes nos solos, mesmo em quantidade pequena, como no caso de solos com elevado grau de alteração secundária. O estudo destes minerais é fundamental para o entendimento do comportamento físico-químico dos solos, no entanto, as técnicas utilizadas nem sempre tem permitido a sua concentração adequada, de forma a facilitar o seu estudo. Por isso, este trabalho teve como objetivo analisar a concentração de argilominerais filossilicatos com estrutura 2:1 através da técnica de dissolução seletiva de óxidos e caulinita, visando o seu estudo por difratometria de raios-X e por análise térmica. As amostras analisadas foram coletadas no Rio Grande do Sul, em diferentes condições climáticas, em perfis de Neossolos (RRd e RRe), Latossolo (LVd) e Vertissolo (VEo). A fração argila dos horizontes A e B destes solos foram separadas e submetidas ao tratamento com ditionito-citrato-bicarbonato de sódio e posteriormente com NaOH a quente em 10 concentrações diferentes, a partir de 0,5 até 5 mol L-1. Para a caracterização mineralógica utilizou-se as técnicas de difração de raios-X (DRX), termogravimetria (TG) e análise térmica diferencial (ATD). Os resultados obtidos pelas análises de difratometria de raios-X mostraram que para solos mais intemperizados como o Latossolo a solução de NaOH não contribui para a concentrar os minerais 2:1. No entanto, para o Vertissolo a solução de NaOH 4,0 mol L-1 foi mais eficiente na concentração desses minerais. Os Neossolos apresentaram comportamento distinto, sendo que para o RRd nenhuma concentração da solução de NaOH foi eficiente e para o RRe a concentração de 2,5 mol L-1 da solução de NaOH foi a mais adequada para a concentração dos argilominerais 2:1. A extração da caulinita e gibbsita através da solução de NaOH foi apenas parcial para a caulinita, observou-se a permanência deste mineral em boa parte das concentrações. As análises térmicas mostraram predominância de caulinita em relação à gibbsita e minerais 2:1 nas amostras desferrificadas. O tratamento mais eficiente, pela análise térmica, para concentração de minerais 2:1 foi o NaOH 4 mol L-1 para as amostras LVd B, RRh A, RRe A e VEo A e o tratamento NaOH 3 mol L-1 para as amostras LVd A e VEo B. A concentração relativa de 2:1 foi maior nas amostras com caráter distrófico.
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41

Kalina, Lukáš. "Fosfátová pojiva." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216349.

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The work deals with the preparation and study of polyphosphate composites. Aluminum phosphates provide some unusual properties like high-heat resistance in terms of inorganic binders. The addition of chromium in the form of Cr2O3 or directly the bond with the aluminum-chromium-phosphate can improve the properties of this binder. Highly viscous Al2Cr(H2PO4)9 and Al3Cr(H2PO4)12 binders were prepared by dissolving Al(OH)3 and CrO3 in 85% phosphoric acid, and mixed with Al2O3 and Cr2O3 fillers. The composites were cured in the furnace at 150 °C for 24 h under pressure of 10 MPa. During the annealing at temperatures up to 1 500 °C changes in chemical structure of the cured composites were observed, leading to the understanding of the creation of crystalline phases and their eventual changes. The characterization of binders was mainly based on FT-IR, EDAX, TG-DTA and optical microscopy analyses.
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42

Both, Jane Mari Correa. "A desinfecção como barreira sanitária na prevenção de doenças transmitidas por alimentos (DTA): sensibilidade de amostras de Staphylococcus aureus isoladas em alimentos no IPB-Lacen/RS, hipoclorito de sódio." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/10411.

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As doenças transmitidas por alimentos provocam perdas humanas, sociais e econômicas, sendo que, para a prevenção de suas ocorrências, a higienização (limpeza e desinfecção) do ambiente de processamento e manipulação é procedimento de relevante importância. Para promover a segurança microbiológica dos alimentos, os compostos inorgânicos liberadores de cloro livre estão entre os desinfetantes químicos mais utilizados. No entanto, as evidências indicam que não há agente químico antimicrobiano frente aos quais os microrganismos não apresentem ou não possam ser selecionados por algum grau de resistência. Para obter dados sobre a ação do cloro como barreira sanitária, o objetivo deste trabalho foi o de verificar, frente ao hipoclorito de sódio, a sensibilidade de 32 amostras de Staphylococcus aureus isoladas no IPB/LACEN/RS de alimentos envolvidos em surtos de DTA entre os anos 2002 e 2006. Através do teste de suspensão, simularam-se condições de uso: concentração de 200 ppm de cloro livre, na ausência e na presença de matéria orgânica (1% de leite U.H.T. integral); subconcentração de 100 ppm de cloro livre; e quatro tempos de contato (5, 10, 15 e 30 minutos). A 200 ppm, na ausência de matéria orgânica, as 32 amostras foram sensíveis, sendo que, aos 10 minutos, 31 delas já estavam inativadas. A 200 ppm, na presença de matéria orgânica, mesmo aos 30 minutos de contato, 27 foram resistentes. Com 100 ppm de cloro livre, foram necessários 30 minutos de contato para que 24 amostras apresentassem sensibilidade. Concluiu-se que a sensibilidade das amostras foi influenciada pela concentração, pela presença de matéria orgânica e pelo tempo de contato. Considerando as condições do experimento quanto à efetividade do cloro como barreira sanitária em DTA, frente ao Staphylococcus aureus, esses três fatores precisam ser levados em consideração.
Foodborne diseases cause human, social and economic losses. Their ocurrence can be avoided chiefly by cleaning and disinfection measures in processing and manipulation premises. Inorganic chlorine compounds are among the most common chemical disinfectants used to promote microbiological food safety. However, evidences indicate that microorganisms are capable to present or develop some degree of resistance to practically every known chemical agent. So, in order to obtain data regarding chlorine compounds as a sanitary barrier, this work evaluated the sensitivity, to sodium hypochlorite, of 32 samples of Staphylococcus aureus isolated at IPB-LACEN/RS from food involved in foodborne diseases outbreaks occurred between 2002-2006. Through the suspension test, usage conditions were simulated: a 200 ppm free chlorine solution in the absence and presence of organic matter (1% UHT whole milk); a subconcentration of 100 ppm free chlorine solution; and four contact times (5, 10, 15 and 30 minutes). At the concentration of 200 ppm, in absence of organic matter, all the 32 samples were sensitive. After 10 minutes,31 of them were already inactivated. At 200 ppm, in presence of organic matter, 27 strains were resistant even after a contact of 30 minutes. At 100 ppm free chlorine concentration, simulating a sub concentration usage, it was necessary a 30 minutes contact to 24 samples demonstrate some sensitivity. It was concluded that the sensitivity of samples was influenced by concentration, presence of organic matter and contact time. In view of the experimental conditions relative to chlorine efficacy as a sanitary barrier, in foodborne diseases associated to Staphylococcus aureus, these three factors must be considered.
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43

Bezděk, Ondřej. "Vliv pH záměsové vody na hydrataci a mechanické vlastnosti cementových kompozitů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2015. http://www.nusl.cz/ntk/nusl-217110.

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This master’s thesis is focused on the effect of mixing water pH value on hydration and mechanical properties of cement composites based on portland cement. Source material was CEM I 42,5 R. Hydration process was analyzed by isoperibolic calorimetry, X-ray diffraction analysis and differential thermal analysis. Compressive and flexural strength was examined as mechanical properties. The samples microstructure was observed by scanning electron microscopy. Influence of mixing water pH value on flexural and compressive strength, retardation of hydration and ratio of individual phases was shown.
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44

Phung-on, Isaratat. "An investigation of reheat cracking in the weld heat affected zone of type 347 stainless steel." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1188419315.

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45

Abrishami, Mahdi. "Dynamic Link Flow Estimation according to Historical Travel Times." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-144583.

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Vast application of ITS and the availability of numerous on-road detection devices has resulted in variety of alternative data sources to be exploited and used in the field of traffic modelling. In this thesis, historical travel times, as an alternative data source, is employed on the developed method to perform dynamic network loading. The developed method, referred to as DNLTT, uses the share of each route available in the route choice set from the initial demand, as well as link travel times to perform the network loading. The output of the algorithm is time-dependent link flows. DNLTT is applied on Stockholm transportation network, where it is expected to have variation in link travel times in different time-periods, due to network congestion. In order to calculate the route shares, a time-sliced OD matrix is used. The historical travel times and the routes in the route choice set are extracted from an existing route planning tool. An available logit model, which considers the route travel time as the only logit parameter, is used for the route share calculation and the network loading is performed according to 2 different methods of DNLTT and DL. The evaluation of results is done for a toy network, where there happen different network states in different time-periods. Furthermore, the model output from Stockholm case study is analyzed and evaluated. The dynamic behavior of DNLTT is studied by analysis of link flows in different time-periods. Furthermore, the resulting link flows from both network loading methods are compared against observed link flows from radar sensors and the statistical analysis of link flows is performed accordingly. DNLTT exhibits a better performance on the toy network compared to DL, where the increasing link travel times cause the link flows to decline in different time-periods. However, the output of the developed method does not resemble the observed link flows for the investigated links in Stockholm case study. It is strongly believed, that the performance of DNLTT on the investigated transportation network potentially improves, in case the historical travel times better resemble the network dynamics. In addition to a more reliable data set, an OD adjustment process in all the time-periods is believed to generate better model output.
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46

Steiner, Joseph Michael. "Phase Transformation Behavior and Hydrogen Cracking Susceptibility in Grade T23 and T24 Steel Welds." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1409039647.

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47

Žáková, Kateřina. "Syntéza keramických materiálů na bázi Ca-Co-O systému." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376785.

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In this work synthesis of structure cobaltites based on Ca-Co-O system is discussed. As major way of synthesis was chosen citric acid method. The document is devided into theoretical and experimental part and also into discussion of observed results. Main focus of literary research is general utilization and function of thermoelectric materials, related thermoeletric effects according to structural defects in crystals. Also topic of cobaltite ceramics is described. Due to the fact that calcium-cobalt oxides are conductive, their use is point of interest in high-temperature and energy applications. During experiments differential thermal and thermogravimetric analysis (TG-DTA), X-Ray diffraction, heat microscopy and scanning electron microscopy were used.
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48

Bryson, Latoya G. "Monomer recovery from nylon carpets via reactive extrusion." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22618.

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Thesis (Ph. D.)--Chemical and Biomolecular Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Muzzy, John D.; Committee Member: Cook, Fred L.; Committee Member: Jones, Christopher W.; Committee Member: Mayor, J. Rhett; Committee Member: Realff, Matthew J.; Committee Member: Schork, F. Joseph.
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49

Tankpinou, Kiki Yvette sedjro. "Caractérisation minéralogique, thermique et microscopique des sols fins en technique routière." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0227/document.

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En vue de la réduction des problèmes engendrés par les phénomènes de retrait-gonflement des sols dans la dépression de la Lama au Sud du Bénin, nous avons entrepris des recherches dans le but de maîtriser le comportement de ces sols. Six échantillons de sols fins dont quatre argileux de cette région ont été prélevés. Différents essais ont été réalisés : une caractérisation macroscopique concernant les propriétés mécaniques et géotechniques et les essais microscopiques prenant en compte les analyses chimiques, thermiques, minéralogiques et microstructurales. Les sols étudiés sont constitués de différents minéraux argileux. Celle à structure fibreuse est à l'origine d’un comportement macroscopique particulier décelé par l’essai de gonflement libre. Les essais ont confirmé le fort potentiel de gonflement et de retrait de certains sols qui sont donc à l'origine des fortes dégradations rencontrées.Les résultats montrent que les sols traités se distinguent par les performances mécaniques acquises et peuvent être utilisés à différents niveaux de la chaussée selon leur teneur en liant.Les différentes méthodes utilisées ont révélé des facettes particulières de l'étude de traitement des sols fins. Principalement, nous avons noté que les informations apportées par les observations au Microscope Electronique à Balayage, les analyses thermiques et les analyses de Diffraction aux Rayons X ont permis de compléter l’analyse des résultats géotechniques. En somme, les méthodes de caractérisation géotechnique permettent d’avoir une idée générale du potentiel de gonflement, mais pour les études d’envergure, la réalisation d’études microscopiques est primordiale
To help reduce the problems caused by phenomena due to the shrink-swell soil in the depression of the Lama in southern Benin, we have undertaken research in order to control the behavior of these soils. Six soil samples, including four clay from this area were taken. Different types of tests were performed: a macroscopic characterization concerning mainly mechanical and geotechnical properties and microscopic tests taking into account the chemical, thermal, microstructural and mineralogical analysis. The soils studied consist of different clay minerals. The fibrous structure is at the origin of a particular macroscopic behavior detected by the free swell test. The tests confirmed the potential for swelling and shrinking of some soils that are causing heavy damage.Three soils treated with different contents at Binder Hydraulic Road, were subjected to several tests. The results show that these soils are distinguished by the acquired mechanical performance and may be used at different levels of the floor according to binder content.Also, the different methods revealed specific facets of fine soil treatment study. Mainly, we noted that the information provided by the observations scanning electron microscope, thermal analysis and the analysis of diffraction X-Ray are very important and helped complete the analysis of geotechnical results for soil treatment. In sum, geotechnical characterization methods used to get a general idea of the swelling potential, but for large-scale studies, conducting microscopic studies is paramount
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50

Lima, Rodrigo Freitas. "Reconstrução em 3D de imagens DICOM cranio-facial com determinação de volumetria de muco nos seios paranasais." Universidade Presbiteriana Mackenzie, 2015. http://tede.mackenzie.br/jspui/handle/tede/1465.

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Made available in DSpace on 2016-03-15T19:37:58Z (GMT). No. of bitstreams: 1 RODRIGO FREITAS LIMA.pdf: 13768169 bytes, checksum: 153d5257eed9a0961aaeaac94e224f89 (MD5) Previous issue date: 2015-08-05
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Paranasal sinus are important objects of study to rhinosinusitis diagnostic, having some papers related incidence between asthma and allergic rhinitis.Many applications can calculate to various parts of the human body, getting a CT scan or MRI input, and returning information about the region of interest observed as volume and area. The accumulated mucus in the sinuses is one of the areas of interest that have not yet been implemented methods for the calculation of volume and area. In the present scenario, the patient monitoring is done visually, depending largely on perception of the evaluator. Therefore, we seek to implement more accurate metrics to facilitate medical care to the patient and it can help prevent the worsening of rhinitis in a given patient, developing mechanisms of visual and numerical comparison, where it is possible observe the progress of treatment. This work contains a detailed study of how certain existing techniques, combined into one methodology can segment and calculate the accumulated mucus in the maxillary sinus. In addition to techniques such as Thresholding, Gaussian filter, Mathematical Morphology, Metallic Artifacts Reduction during processing and segmentation, MUNC and DTA to calculate the volume and area, and visualization techniques as the Marching Cubes, it was also necessary some adjustments in the algorithm for limit the region of interest where the thresholding combined with the gaussian filter has not been effective of retaining edges. The application will use two open source platforms, one for processing, ITK, and another for visualization, VTK. The results demonstrated that it is possible to perform segmentation and the calculation with the use of platforms as well as the methodology used is adequate to solve this problem.
Os seios paranasais são importantes objetos de estudo para o diagnóstico de rinossinusites, tendo alguns estudos relacionado a incidência de asma na fase adulta a quadros de rinite alérgica na infância. Muitas aplicações atendem a diversas partes do corpo humano, obtendo de entrada uma tomografia computadorizada ou ressonância magnética, e devolvendo, muitas vezes, números que dizem respeito ao objeto de interesse observado, como volume e área. O muco acumulado nos seios paranasais é uma das regiões de interesse que ainda não tiveram métodos implementados para o cálculo do volume e área. No cenário atual, o acompanhamento do paciente é feito de forma visual, dependendo muito da percepção do avaliador. Portanto, busca-se a implementação de métricas mais precisas para facilitar o acompanhamento médico ao paciente e ajudar na prevenção do agravamento de um quadro de rinite em um determinado paciente, criando mecanismos de comparação visual e numérica, onde é possível observar a evolução do tratamento. Este trabalho contém um estudo detalhado de como determinadas técnicas existentes, combinadas em uma metodologia, podem segmentar e calcular o muco acumulado nos seios paranasais maxilares. Além de técnicas como a Binarizacão, Filtro Gaussiano, Morfologia Matemática, Redução de Ruídos Metálico durante o processamento e segmentação, MUNC e DTA para o cálculo do volume e área, e técnicas de visualização como o Marching Cubes, foram necessários também ajustes no algoritmo para limitar a área segmentada onde a binarizacão combinada ao filtro não foi capaz de manter as bordas da região de interesse. A aplicação fará uso de duas plataformas de código livre, sendo uma para o processamento, ITK, e outra para visualização de imagens, VTK. Os resultados demonstraram que é possível realizar a segmentação e o cálculo com o uso das plataformas, bem como a metodologia empregada é adequada a resolução deste problema.
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