Academic literature on the topic 'TG/DTA'
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Journal articles on the topic "TG/DTA"
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Jorda, J. L. "DTA/TG coupling." Journal of Thermal Analysis 48, no. 3 (March 1997): 585–96. http://dx.doi.org/10.1007/bf01979505.
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Hatakeyama, Tatsuko. "DSC,DTA,TG." Kobunshi 40, no. 4 (1991): 264–67. http://dx.doi.org/10.1295/kobunshi.40.264.
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Sumadiyasa, Made, I. Putu Suardana, and Nyoman Wendri. "DTA-TG Analysis of Gd0.95La0.05Ba1.95Sr0.05Cu3Oy Compounds." BULETIN FISIKA 21, no. 1 (February 1, 2020): 33. http://dx.doi.org/10.24843/bf.2020.v21.i01.p06.
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The sintering temperature is played a vital role in the evolution of phase structure, microstructure, and the properties of the superconductor. In this study, the Gd0.9La0.1Ba1.95Sr0.05Cu3O7-d phase compound has been synthesized by the wet method using HNO3 as a solvent. The samples were divided into two groups. The first sample was calcined at 400 °C for 2 hours + 500 °C for 2 hours + 600 °C for 6 hours. The second sample treated by the same process and then continued by heating at 900 °C for 15 minutes. The effect of the calcination temperature for the synthesis of Gd0.9La0.1Ba1.95Sr0.05Cu3O7-d bulks was investigated using the DTA-TG method. The results showed that the optimum reaction temperature for the formation of Gd0.9La0.1Ba1.95Sr0.05Cu3O7-d phase was 938 °C. The additional heating temperature e.g. 900 °C for 15 minutes on the calcination process can reduce the optimum formation temperature of Gd0.9La0.1Ba1.95Sr0.05Cu3O7-d compounds by 20 °C. The peritectic melting reaction temperatures of the sample without the addition of heating and with the addition of heating at temperature 900 °C for 15 minutes are 1032°C and 1035°C, respectively. The melting temperatures of both samples are 1164 °C and 1200 °C.
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SAWADA, Yutaka, Taro SHIGARAKI, Shigeyuki SEKI, Makoto OGAWA, Tetsuya SENDA, Toshikazu NISHIDE, and Jun-ichi MATSUSHITA. "TG-DTA-MS of Indium Acetate." Journal of the Mass Spectrometry Society of Japan 46, no. 4 (1998): 292–95. http://dx.doi.org/10.5702/massspec.46.292.
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Brendel, Wulf, Theodoros Samartzis, Claus Brendel, and Bernt Krebs. "TG and DTA investigations on hexaiodometallates." Thermochimica Acta 83, no. 1 (January 1985): 167–72. http://dx.doi.org/10.1016/0040-6031(85)85808-1.
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Arii, Tadashi, Yutaka Sawada, Kiyokata Iizumi, Katsuya Kudaka, and Shigeyuki Seki. "TG-DTA-MS of chromium(III) formate." Thermochimica Acta 352-353 (July 2000): 53–60. http://dx.doi.org/10.1016/s0040-6031(99)00437-2.
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Dakka, S. M. "TG/DTA/MS of poly(methyl methacrylate)." Journal of Thermal Analysis and Calorimetry 73, no. 1 (2003): 17–24. http://dx.doi.org/10.1023/a:1025165020404.
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Dakka, S. M. "TG/DTA/MS of Poly(Methyl Methacrylate)." Journal of Thermal Analysis and Calorimetry 74, no. 3 (2003): 729–34. http://dx.doi.org/10.1023/b:jtan.0000011005.54630.cd.
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Poiesz, Kate B., Carol L. Grundner, and Nancy L. Redman-Furey. "Monitoring hydration state conversion by TG-DTA." Journal of Thermal Analysis and Calorimetry 85, no. 1 (July 2006): 79–86. http://dx.doi.org/10.1007/s10973-005-7350-z.
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Soares, R. W., V. J. Menezes, M. V. A. Fonseca, and J. Dweck. "Characterization of carbonaceous products by TG and DTA." Journal of thermal analysis 49, no. 2 (August 1997): 657–61. http://dx.doi.org/10.1007/bf01996748.
Full textDissertations / Theses on the topic "TG/DTA"
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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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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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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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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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Previous issue date: 2013-03-22Bioidentical 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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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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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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Previous issue date: 2008-02-29Conselho 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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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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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 SuperiorThe 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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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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Previous issue date: 2014-03-24Since 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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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.
Full textBook chapters on the topic "TG/DTA"
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Almeida, Luis Eduardo Nunes, Aureomar F. Martins, Susane R. Gomes, and Flavio A. L. Cunha. "Thermal Decomposition Kinetics Studies of HTPB/Al/AP Solid Propellants Formulated With Iron Oxide Burning Rate Catalyst in Nano and Micro Scale." In Energetic Materials Research, Applications, and New Technologies, 211–33. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-2903-3.ch010.
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The thermal decomposition kinetics of ammonium perchlorate (AP)/hydroxyl-terminated-polybutadiene (HTPB) samples, with Iron Oxide catalyst at nano and micro scale were studied by thermal analysis techniques at different heating rates in dynamic nitrogen atmosphere. The exothermic reaction kinetics was studied by differential scanning calorimetry (DSC) in isothermal conditions. The Arrhenius kinetic parameters were obtained by Flynn-Wall and Ozawa Kissinger and Starink methods. The propellant samples thermal decomposition was studied simultaneously by TG-DTA. For this purpose, solid propellant grains containing nano and micro scale iron oxide were formulated. The effect of catalysts on the propellant burning rate and the propellant initiation sensitivity were also evaluated by friction and impact. The effect of the catalyst in the propellant binder reaction was evaluated by viscosity and mechanical properties. SEM/EDS technique was used to evaluate the iron oxide morphology. Three bench firing tests were performed with rockets motor in order to know the ballistics parameters.
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Ohnishi, Ryuichiro, Kohtaro Issoh, Linsheng Wang, and Masaru Ichikawa. "Novel rhenium based catalysts for direct dehydroaromatization of methane with CO/CO2 towards ethylene and benzene, catalysis and XAFS/TG/DTA/MASS characterization." In Studies in Surface Science and Catalysis, 3603–8. Elsevier, 2000. http://dx.doi.org/10.1016/s0167-2991(00)80582-0.
Full textConference papers on the topic "TG/DTA"
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Zhu, Ning, Yang Li, Qian Wang, and Yong Jiang. "Experimental research on biomass combustion by TG-DTA/MS analysis." In 10th International Energy Conversion Engineering Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2012. http://dx.doi.org/10.2514/6.2012-3721.
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Takata, H., N. Touch, S. Yamaji, and T. Hibino. "Thermal Analysis (TG-DTA) for Identify Organic Matter Conditions in Sediment." In The 9th International Conference on Asia and Pacific Coasts 2017 (APAC 2017). WORLD SCIENTIFIC, 2017. http://dx.doi.org/10.1142/9789813233812_0082.
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Kawaguchi, Munemichi. "Measurement of Thermal Decomposition Temperature and Rate of Sodium Hydride." In 2020 International Conference on Nuclear Engineering collocated with the ASME 2020 Power Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/icone2020-16423.
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Abstract In decommissioning sodium-cooled fast reactors, the operators can be exposed to radiation during dismantling of cold trap equipment (C/T). The C/T is higher dose equipment because the C/T trapped tritium of fission products during the operation to purify the sodium coolant. In this study, thermal decomposition temperature and rate of sodium hydride (NaH) were measured as a fundamental research for development of “thermolysis” process prior to the dismantling. We measured the thermal decomposition temperature and rate using NaH powder (95.3%, Sigma-Aldrich) in alumina pan with ThermoGravimetry-Differential Thermal Analysis (TG-DTA) instrument (STA2500 Regulus, NETZSCH Japan). The heating rates of TG-DTA were set to β = 2.0, 5.0, 10.0 and 20.0 K/min. The DTA showed endothermic reaction and the TG showed two-steps mass-loss over 580K. This first-step mass-loss was consistent with change of chemical composition of the NaH with heating (NaH → Na+1/2H2). The thermal decomposition temperature and rate were obtained from the onset temperature of the mass-loss and the simplified Kissinger plots, respectively. Furthermore, we set to the thermal decomposition temperature of around 590K, and the mass-loss rates were measured. As a result, over 590K, the thermal decomposition occurred actively, and showed good agreement with the estimation curves obtained by the simplified Kissinger plots. The thermal decomposition rate strongly depended on the heating temperature.
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Yuan, Yi-zhe, Yan-Ming Hao, and Wei Wang. "Differential thermal/thermogravimetric analysis (DTA-TG) and thermal expansion anomaly properties of Tm2Fe17 compound." In 2010 International Conference on Mechanic Automation and Control Engineering (MACE). IEEE, 2010. http://dx.doi.org/10.1109/mace.2010.5535696.
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Melane, Chris, Hein Badenhorst, Luxolo Holo, Eino Vuroinen, Brian Rand, and Walter W. Focke. "Oxidative Stability of Carbon by Thermal Gravimetric Analysis." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61423.
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The Pebble Bed Modular Reactor (PBMR) is a High Temperature Gas Cooled nuclear Reactor (HTGR) with numerous inherent passive safety features. Graphite is the most important material of construction for the reactor core and the fuel pebbles. PBMR accident scenarios include uncontrolled air ingress into the reactor. Understanding the high temperature behavior of the graphite materials under such conditions is vital for design and accident modeling purposes [1]. Graphitic materials have a very high thermal stability compared to ordinary organics. The high degradation temperatures are beyond the capability of Differential Scanning Calorimetry (DSC) and thus necessitate the use of Differential Thermal Analysis (DTA) or Thermogravimetric Analysis (TG). The oxidative stability of two graphite samples was investigated using temperature scanning TG. It was found that air oxidation of a natural graphite sample commenced at temperatures that were significantly lower than those observed for a synthetic graphite sample. The natural graphite also showed peculiar bimodal mass loss rates.
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Kutelia, E., O. Tsurtsumia, T. Markus, Ch Chatzicharalampous, T. Kukava, Muhammed Hasan Aslan, Ahmet Yayuz Oral, Mehmet Özer, and Süleyman Hikmet Çaglar. "The DTA-TG Investigation of Non-Crystalizing Super-Pure (up to 8N) Gallium Melt Obtained by the Membrane Technology." In INTERNATIONAL CONGRESS ON ADVANCES IN APPLIED PHYSICS AND MATERIALS SCIENCE. AIP, 2011. http://dx.doi.org/10.1063/1.3663180.
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Otaka, Takeshi, and Yutaka Asako. "Thermal Intumescent Characteristics of Heated Sodium Silicate." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-39393.
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A fire barrier material is made of a rubber in which intumescent materials are mixed. Sodium silicate is one of the intumescent materials which intumesces at low temperature. In this report, the thermal intumescent characteristics of water glass and sodium metasilicate are investigated. Thermal intumescent ratio of water glass and sodium metasilicate were measured using a thermo-gravimetry (TG/DTA) with the heating rate in the range from 1 K/min to 99.9 K/min. As the result, it is clarify that thermal intumescent characteristics depend on the heating rate. Thermal intumescent ratio increases with increasing the heating rate. No intumescence was observed under the condition that the heating rate ranges from 1 K/min to 20 K/min.
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Martinez Sarache, Handel, and Waldir Bizzo. "Study of high-temperature interactions between ashes from cassava harvesting residues and inert materials via DTA/TG and SEM/EDS." In 24th ABCM International Congress of Mechanical Engineering. ABCM, 2017. http://dx.doi.org/10.26678/abcm.cobem2017.cob17-0347.
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Li, J., S. A. Mehta, R. G. Moore, M. G. Ursenbach, H. Ferguson, E. Zalewski, and N. E. Okazawa. "The Research of Oxidation and Ignition Behaviour of Saturated Hydrocarbon Sample With Crude Oils Using TG/DTG and DTA Thermal Analysis Techniques." In Canadian International Petroleum Conference. Petroleum Society of Canada, 2002. http://dx.doi.org/10.2118/2002-201.
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Mozammel, Hoque Md, and Masahiro Ota. "Kinetic Study of Waste Wood and Its Carbonization." In 2002 International Joint Power Generation Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/ijpgc2002-26030.
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This study deals with the conversion of waste wood into solid fuel charcoal. Thermogravimetric and differential thermal analyses techniques are used to investigate the kinetics of thermochemical conversion of waste wood. The thermal degradation characteristics and the kinetic parameters (order of reaction, activation energy and pre-exponential factor) are determined at different heating rates using TG/DTA curves. The decomposition of the components could be modeled by an Arrhenius kinetic expression. The kinetic parameters are determined from the thermogravimetric data by a least square technique. The order of reaction and activation of energy vary from 0.41 to 0.52 and 10.86 to 15.10 kJ/mole respectively. Finally attempts are taken to produce charcoal from the waste wood and the charcoals are characterized in respect of yield, electrical conductivity, ESCA (electron spectroscopy for chemical analysis), XRD (x-ray diffraction) and ignition characteristics.