Dissertations / Theses on the topic 'Pressure differential scanning calorimetry'
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Belkharchouche, Mohamed. "Pressure differential scanning calorimetry studies and its relevance to in-situ combustion." Thesis, University of Salford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280747.
Full textLee, Jaesung. "Calorimetric and microbiological evaluation of bacteria after exposure to food preservation treatments." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1078597088.
Full textTitle from first page of PDF file. Document formatted into pages; contains xvi, 231 p.; also includes graphics (some col.) Includes bibliographical references (p. 212-224). Available online via OhioLINK's ETD Center
Pillar, Rachel Joanne, and rachel pillar@flinders edu au. "The Influence of Rolling Oil Decomposition Deposits on the Quality of 55Al-43.4Zn-1.6Si Alloy Coatings." Flinders University. School of Chemistry, Physics and Earth Sciences, 2007. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20080108.132120.
Full textBatisai, Eustina. "Synthesis and sorption studies of porous metal-organic hosts." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79803.
Full textENGLISH ABSTRACT: The first part of this study describes the synthesis of new porous materials from basic building blocks. Five structurally related ligands namely: N,N'-bis(3-pyridylmethyl)-naphthalene diimide (L1), N,N'-bis(4-pyridylmethyl)-naphthalene diimide (L2), N,N'-bis(4-pyridylmethyl)- pyromellitic diimide (L3), N,N'-bis(3-pyridylmethyl)-pyromellitic diimide (L4) and 2-(pyridin-4- ylmethyl)-benzene tricarboxylic anhydride (L5) were synthesised. Ligands L1 and L2 were reacted with metal nitrates and carboxylates as co-ligands in a systematic manner with a view to obtaining potentially porous 3–D coordination polymers. Ten structurally diverse coordination polymers were obtained and they were characterised by single-crystal X-ray diffraction, powder X-ray diffraction and thermogravimetric analysis. Four of these compounds absorb moderate amounts of CO2 and, in addition, show sorption selectivity towards CO2 over N2. The reaction of L3 and L4 with transition metal halides yielded two 1–D chains, while the reaction of L5 with transition metal nitrates yielded seven coordination polymers of which four are 2–D and three are 1–D. Of the 2–D structures three are isostructural. The second part of this work describes a variable pressure study of a flexible metal-organic framework [Zn2(BDC)2(BPY)] (BPY = 4,4 -bipyridine and BDC = 1,4-benzene dicarboxylic acid). [Zn2(BDC)2(BPY)] is one of the few examples of a flexible metal-organic framework that undergoes phase transformations in response to gas pressure. The high pressure sorption recorded for this metal-organic framework displays two inflection steps in the pressure range 0 to 30 bar, possibly indicating two phase transformations. The gas-loaded structures for each phase transformation were determined by means of single-crystal X-ray diffraction. High-pressure differential scanning calorimetry was also carried out on the system in order to determine accurate gate-opening pressures, as well as the energies involved with each phase transformation. The results correlate with those obtained from single-crystal X-ray diffraction and high-pressure sorption. The final section reports the mechanochemical synthesis of two Werner complexes [NiCl2(4- PhPy)4] (1), [CoCl2(4-PhPy)4] (2) and their corresponding solid solution [Ni0.5Co0.5Cl2(4-PhPy)4] (3) (PhPy = phenyl pyridine). The solid solution could only be formed by mechanochemical synthesis and not by conventional solution crystallisation methods. The solid solution exhibits sorption properties that differ from those of the pure compounds.
AFRIKAANSE OPSOMMING: Die eerste deel van hierdie studie beskryf die sintese van nuwe poreuse stowwe uit basiese boublokke. Vyf struktureel verwante ligande naamlik: N,N'-bis(3-piridielmetiel)-naftaleen diimied (L1), N,N'-bis(4-piridielmetiel)-naftaleen diimied (L2), N,N'-bis(4-piridielmetiel)- piromellitien diimied (L3), N,N'-bis(3-piridielmetiel)-piromellitien diimied (L4) en 2-(piridiel-4- ielmetiel)benseen trianhidried (L5) is gesintetiseer. Ligande L1 en L2 is gereageer met metaal nitrate en karboksielsure as mede-ligande in 'n sistematiese wyse met 'n oog op die verkryging van potensieel poreuse 3–D koördinasie polimere. Tien struktureel diverse koördinasie polimere is verkry en hulle is gekarakteriseer deur enkel-kristal X-straal-diffraksie, poeier X-straal diffraksie en termo-analise (thermal analysis). Vier van hierdie verbindings het matige hoeveelhede CO2 geabsorbeer en, bykomend, wys sorpsie selektiwiteit van CO2 oor N2. Die reaksie van L3 en L4 met oorgangsmetaalhaliede het twee 1–D kettings gevorm, terwyl die reaksie van L5 met oorgangsmetaal nitrate sewe koördinasie polimere opgelewer het, waarvan vier 2–D en drie 1–D polimere is. Van die 2–D polimere het drie vergelykbare strukture. Die tweede deel van hierdie werk beskryf 'n veranderlike druk studie van 'n buigsame metaalorganiese raamwerk [Zn2(BDC)2(BPY)] (BPY = 4,4-bipiridien en BDC = 1,4-benseen dikarboksielsuur). [Zn2(BDC)2(BPY)] is een van die min voorbeelde van 'n buigsame metaalorganiese raamwerk wat fase transformasies (phase transformations) ondergaan in respons op ‘n verandering in gas druk. Die hoë-druk sorpsie aangeteken vir hierdie metaal-organiese raamwerk vertoon twee infleksie stappe in die gebestudeerde druk gebied (0 tot 30 bar), wat moontlik op twee fase transformasies dui. Die gas-gelaaide strukture vir elke fase transformasie is bepaal deur middel van enkel-kristal X-straal-diffraksie. Hoë-druk differensiële skandeer kalorimetrie (differential scanning calorimetry) is ook uitgevoer op die stelsel ten einde dié akkurate hekopenings druk, sowel as die energie betrokke by elke fase transformasie te bepaal. Die resultate stem ooreen met dié verkry vanaf enkel-kristal X-straal diffraksie en hoë-druk sorpsie. Die finale afdeling bespreek die meganochemiese sintese van twee Werner komplekse [NiCl2(4-PhPy)4] (1) en [COCl2(4-PhPy)4] (2) en hul ooreenstemmende vaste oplossing (solid solution) [Ni0.5Co0.5Cl2(4-PhPy)4] (3). Die vaste oplossing kan slegs gevorm word deur meganochemiese sintese en nie deur konvensionele oplossing kristallisasie metodes. Die vaste oplossing vertoon sorpsie eienskappe wat verskil van dié van die suiwer verbindings.
Santos, Anne Gabriella Dias. "Avalia??o da estabilidade t?rmica e oxidativa dos biodieseis de algod?o, girassol, dend? e sebo bovino." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17619.
Full textThe search for new sources of environmentally friendly energy is growing every day. Among these alternative energies, biodiesel is a biofuel that has had prominence in world production. In Brazil, law 11.097, determine that all diesel sold in the country must be made by mixing diesel/biodiesel. The latter called BX, , where X represents the percent volume of biodiesel in the diesel oil, as specified by the ANP. In order to guarantee the quality of biodiesel and its mixtures, the main properties which should be controlled are the thermal and oxidative stability. These properties depend mainly of the chemical composition on the raw materials used to prepare the biodiesel. This dissertation aims to study the overall thermal and oxidative stability of biodiesel derived from cotton seed oil, sunflower oil, palm oil and beef tallow, as well as analyze the properties of the blends made from mineral oil and biodiesel in proportion B10. The main physical-chemical properties of oils and animal fat, their respective B100 and blends were determined. The samples were characterized by infrared and gas chromatography (GC). The study of thermal and oxidative stability were performed by thermogravimetry (TG), pressure differential scanning calorimeter (PDSC) and Rancimat. The obtained biodiesel samples are within the specifications established by ANP Resolution number 7/2008. In addition, all the blends and mineral diesel analyzed presented in conformed withthe ANP Regularion specifications number 15/2006. The obtained results from TG curves data indicated that the cotton biodiesel is the more stable combustible. In the kinetic study, we obtained the following order of apparent activation energy for the samples: biodiesel from palm oil > sunflower biodiesel > tallow biodiesel > cotton biodiesel. In terms of the oxidative stability, the two methods studied showed that biodiesel from palm oil is more stable then the tallow. Within the B100 samples studied only the latter were tound to be within the standard required by ANP resolution N? 7. Testing was carried out according to the EN14112. This higher stability its chemical composition
A busca por novas fontes de energia, que sejam ecologicamente corretas, cresce a cada dia. Dentre essas energias alternativas, o biodiesel ? um dos biocombust?veis que vem tendo destaque na produ??o mundial. No Brasil, a Lei n? 11.097, determina que todo diesel vendido no pa?s, deve ser constitu?do pela mistura de ?leo diesel/biodiesel, denominado BX, onde X representa o percentual em volume de biodiesel no ?leo diesel, conforme especifica??o da Ag?ncia Nacional do Petr?leo (ANP). Entre as principais propriedades que devem ser controladas para garantir a qualidade do biodiesel est?o as estabilidades t?rmica e oxidativa, as quais dependem, basicamente, da composi??o da mat?ria prima utilizada. Este trabalho tem como objetivo estudar a estabilidade t?rmica e oxidativa de biodieseis provenientes dos ?leos de algod?o, girassol, dend? e do sebo bovino, assim como analisar as propriedades das blendas feitas do ?leo mineral com biodiesel, na propor??o B10. Foram determinadas as principais propriedades f?sico-qu?micas dos ?leos vegetais e gordura animal, das respectivas amostras de B100 e suas misturas, al?m de caracteriza??es atrav?s de infravermelho e cromatografia a g?s. O estudo das estabilidades t?rmica e oxidativa foram realizados atrav?s de Termogravimetria (TG), Calorimetria Explorat?ria Diferencial sob Press?o (PDSC) e Rancimat. As amostras de biodiesel obtidas est?o dentro das especifica??es estabelecidas pela Resolu??o da ANP No7/2008. As misturas analisadas e o diesel mineral apresentaram todos os resultados em conformidade com as especifica??es da Portaria da ANP N?15/2006. Os resultados obtidos via TG apontam o biodiesel de algod?o como o mais est?vel. No estudo cin?tico, obteve-se a seguinte ordem de energia de ativa??o aparente: biodiesel de dend? > biodiesel de girassol > biodiesel de sebo > biodiesel de algod?o. Em rela??o ? estabilidade oxidativa os resultados obtidos via PDSC e Rancimat indicaram que o biodiesel de dend? foi o mais est?vel, e em seguida o de sebo. Dentre os B100 estudados, o de dend? e sebo bovino, se encontraram dentro dos padr?es exigidos na Resolu??o ANP N?7 (tempo de indu??o 6h), os ensaios foram realizados de acordo com a norma Europ?ia EN14112, a temperatura de 110?C. A maior estabilidade do biodiesel de dend? pode ser atribu?do ? sua composi??o qu?mica
Thompson, M. "Matrix effects in differential scanning calorimetry." Thesis, Open University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281223.
Full textNikolopoulos, Christos. "Mathematical modelling of modulated-temperature differential scanning calorimetry." Thesis, Heriot-Watt University, 1997. http://hdl.handle.net/10399/659.
Full textDumitrescu, Oana Roxana. "Simultaneous differential scanning calorimetry : Fourier Transform infrared spectroscopy." Thesis, Cranfield University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.421231.
Full textJiang, Zhong. "Temperature modulated differential scanning calorimetry : modelling and applications." Thesis, University of Aberdeen, 2000. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU603190.
Full textMiotto, Fernanda. "Reação de desinserção em SbxCoSb3-x." reponame:Repositório Institucional da UCS, 2010. https://repositorio.ucs.br/handle/11338/566.
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The compound SbxCoSb3-x was produced at high pressures and high temperatures in a self-insertion reaction from the binary skutterudite CoSb3. The self-insertion reaction is characterized by the collapse of Sb atoms to the 2a site, into the cage formed by the Co and Sb atoms in the skutterudite structure. The opposite reaction, i.e., Sb desinsertion, occurs when the SbxCoSb3-x compound is heated at room pressure. This desinsertion reaction was followed by means of differential scanning calorimetry (DSC), X-ray diffraction (XRD) and electrical resistivity measurements, and its study constitutes the main objective of this work. The CoSb3 sample was synthesized as described in the literature. The synthesis was confirmed by XRD, and the presence of contaminant phases was not observed. Cylindrical samples of the SbxCoSb3-x phase were obtained by submitting CoSb3 at pressures of 7.7 GPa and temperatures up to 550ºC, with the aid of a toroidal high pressure cell available at the Laboratório de Altas Pressões e Materiais Avançados - LAPMA in the Instituto de Física of the Universidade Federal do Rio Grande do Sul - IF/UFRGS. The presence of the SbxCoSb3-x phase was confirmed by XRD analysis. In order to determine the electrical resistivity of samples rich in SbxCoSb3-x phase, a DC system was developed which is applicable to small volume cylindrical samples such as those obtained at high pressures and high temperatures. The calibration of the DC system was made by measurements of the electrical resistivity of reference materials (NIST-SRM 1461 and NIST-SRM 8426). The DSC measurements revealed the presence of two thermal events. An endothermic peak was observed at 118ºC which is not associated to structural changes neither significant variation in the electrical resistivity. The exothermic event that starts at 180ºC is the signature of the desinsertion of Sb atoms from the skutterudite cage, as verified by XRD analysis and electrical measurements. After heating to 350°C, the sample rich in the SbxCoSb3-x phase converts back to the stable phase, CoSb3. The desinsertion reaction follows a first-order kinetics, with a transition enthalpy of approximately 50 J/g and an activation energy of 83 kJ/mol. The electrical resistivity at room temperature of samples rich in SbxCoSb3-x is about ten times smaller than that of CoSb3. This result, along with a possible low thermal conductivity, suggests that SbxCoSb3-x may constitute a high performance thermoelectric material.
Snell, Andrew John Roger. "Application of Differential Scanning Calorimetry to Characterize Thin Film Deposition Processes." Cleveland State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=csu1280943337.
Full textGouni, Sreeja Reddy. "Cure Kinetics of Benzoxazine/Cycloaliphatic Epoxy Resin by Differential Scanning Calorimetry." Thesis, California State University, Long Beach, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10689461.
Full textUnderstanding the curing kinetics of a thermoset resin has a significant importance in developing and optimizing curing cycles in various industrial manufacturing processes. This can assist in improving the quality of final product and minimizing the manufacturing-associated costs. One approach towards developing such an understanding is to formulate kinetic models that can be used to optimize curing time and temperature to reach a full cure state or to determine time to apply pressure in an autoclave process. Various phenomenological reaction models have been used in the literature to successfully predict the kinetic behavior of a thermoset system. The current research work was designed to investigate the cure kinetics of Bisphenol-A based Benzoxazine (BZ-a) and Cycloaliphatic epoxy resin (CER) system under isothermal and nonisothermal conditions by Differential Scanning Calorimetry (DSC). The cure characteristics of BZ-a/CER copolymer systems with 75/25 wt% and 50/50 wt% have been studied and compared to that of pure benzoxazine under nonisothermal conditions. The DSC thermograms exhibited by these BZ-a/CER copolymer systems showed a single exothermic peak, indicating that the reactions between benzoxazine-benzoxazine monomers and benzoxazine-cycloaliphatic epoxy resin were interactive and occurred simultaneously. The Kissinger method and isoconversional methods including Ozawa-Flynn-Wall and Freidman were employed to obtain the activation energy values and determine the nature of the reaction. The cure behavior and the kinetic parameters were determined by adopting a single step autocatalytic model based on Kamal and Sourour phenomenological reaction model. The model was found to suitably describe the cure kinetics of copolymer system prior to the diffusion-control reaction. Analyzing and understanding the thermoset resin system under isothermal conditions is also important since it is the most common practice in the industry. The BZ-a/CER copolymer system with 75/25 wt% ratio which exhibited high glass transition temperature compared to polybenzoxazine was investigated under isothermal conditions. The copolymer system exhibited the maximum reaction rate at an intermediate degree of cure (20 to 40%), indicating that the reaction was autocatalytic. Similar to the nonisothermal cure kinetics, Kamal and Sourour phenomenological reaction model was adopted to determine the kinetic behavior of the system. The theoretical values based on the developed model showed a deviation from the obtained experimental values, which indicated the change in kinetics from a reaction-controlled mechanism to a diffusion-controlled mechanism with increasing reaction conversion. To substantiate the hypothesis, Fournier et al?s diffusion factor was introduced into the model, resulting in an agreement between the theoretical and experimental values. The changes in cross-linking density and the glass transition temperature (Tg) with increasing epoxy concentration were investigated under Dynamic Mechanical Analyzer (DMA). The BZ-a/CER copolymer system with the epoxy content of less than 40 wt% exhibited the greatest Tg and cross-linking density compared to benzoxazine homopolymer and other ratios.
Song, Mo. "Applications of modulated-temperature differential scanning calorimetry to multi-component polymer materials." Thesis, Lancaster University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337256.
Full textMartin, A. C. S. "Comb shaped polymer-salt systems : A.C. conductivity and differential scanning calorimetry studies." Thesis, University of Stirling, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382751.
Full textKuntz, Michael. "Quantifying Isothermal Solidification Kinetics during Transient Liquid Phase Bonding using Differential Scanning Calorimetry." Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/890.
Full textGoodman, M. "Differential scanning calorimetry and permeation studies of penetration enhancer and human skin interactions." Thesis, University of Bradford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374906.
Full textHill, Vivienne Lucy. "An investigation into the use of MTDSC as a technique for the characterisation of pharmaceutical materials." Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322735.
Full textHirachand, Katan. "The formation, decomposition and inhibition of clathrate hydrate systems measured by differential scanning calorimetry." Thesis, King's College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324673.
Full textPinto, Rafaela Rocha 1985. "Determinação da capacidade calorífica a pressão constante de ácidos graxos através da calorimetria exploratória diferencial." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266859.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Nos últimos anos tem aumentado o interesse em combustíveis oriundos de fontes renováveis como é o caso do biodiesel. Tendo em vista que os ácidos graxos são componentes de óleos e gorduras, usados para a produção do biodiesel em reações de transesterificação, e cujas propriedades ainda são bastante escassas na literatura, o objetivo do presente trabalho foi o de contribuir com dados experimentais de capacidade calorífica (cp) de ácidos graxos, constituintes de óleos e gorduras. Tais dados são necessários para os balanços de energia e para o projeto de equipamentos visando a purificação de óleos, bem como para o cálculo de reações químicas. A análise térmica diferencial é uma técnica dinâmica que vem sendo muito utilizada na determinação de dados térmicos, como capacidade calorífica, temperaturas de mudanças de estado, determinação da pureza de substâncias, entre outras. O cp é a medida da quantidade de energia necessária por unidade de massa (ou mol) de uma substância para elevar sua temperatura em um grau. Neste trabalho foram determinados os dados de cp dos seguintes ácidos graxos em fase líquida e pressão ambiente: ácido caprílico (C8:0), ácido cáprico (C10:0), ácido láurico (C12:0), ácido mirístico (C14:0), ácido palmítico (C16:0), ácido esteárico (C18:0), ácido oléico (C18:1) e ácido linoléico (C18:2). Para determinar a capacidade calorífica dos ácidos graxos, foi utilizado o Calorímetro Exploratório Diferencial - DSC da TA Instruments. Os dados experimentais foram processados pelo método do software Thermal Specialty Library versão 2.2 e pelo método da Amplitude. Os resultados mostraram que a capacidade calorífica aumenta com a temperatura e com o tamanho da cadeia carbônica. Entre os métodos avaliados não houve diferença entre os resultados obtidos. Os dados experimentais foram comparados com dados obtidos pelo método de contribuição de grupos e os desvios relativos chegaram a 15 %. O intervalo de temperatura de exploração foi de 308 K (35 ºC) a 573 K (300 ºC)
Abstract: In recent years the interest in renewable sources of fuels such as biodiesel has been increasing. Considering that fatty acids are components of fats and oils, used in the production of biodiesel in the transesterification reactions, and whose properties are still quite scarce in the literature, the purpose of this study was to contribute with experimental data of heat capacity (cp) of fatty acid constituents of oils and fats. Such data are needed for energy balances, for the design of equipment aimed at purification of oils and also for the calculation of chemical reactions. Differential thermal analysis is a dynamic technique that has been widely used in the determination of thermal data such as heat capacity, purity determination, phase change temperatures and others. The cp is the amount of energy required per unit mass (or mole) of a substance to raise its temperature by one degree. The cp were determined, in liquid phase and at atmospheric pressure, of the following fatty acids: caprylic acid (C8:0), capric acid (C10:0), lauric acid (C12:0), myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1) and linoleic acid (C18:2). To determine the heat capacities of the fatty acids, a Differential Scanning Calorimeter - DSC, of TA Instruments, was used. The experimental data were processed using the Thermal Specialty Library (version 2.2) software and the method of vertical displacement. The results showed that the heat capacity increased with temperature and with the length of the alkyl chains. A comparison of the two methods showed no difference between the resulting information, and when the data from the experiments were compared with the data obtained from the group contribution method, there was a relative deviation of 15%. The working temperature range was from 308 K (35 ºC) to 573 K (300 ºC)
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química
Bunyaraksh, S. S. "Relation between dyeability of polyester yarn and its structure : Studied by density measurements and differential scanning calorimetry." Thesis, University of Leeds, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379540.
Full textKirby, Erin. "Study of low temperature nondenaturational conformational change of bovine alpha-chymotrypsin by slow- scanrate differential scanning calorimetry." Thesis, Texas Woman's University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1550669.
Full textSlow-scan-rate differential scanning calorimetry of enzymes can detect conformational changes which are under kinetic control and not observable at standard scan rates. This method detected a nondenaturational conformational change of bovine &agr;-chymotrypsin at 286 K. This temperature occurs between bovine physiological temperature of 312 K and x-ray crystallography temperature, typically 277 K. This suggests that there are two conformers of &agr;-chymotrypsin, a low temperature conformation and a physiological temperature conformation. The low-temperature to physiological-temperature conformational change has a high activation energy and thus is temperature dependent. The equilibrium thermodynamic changes suggest a reordering of the enzyme structure to give more favorable inter-residue interactions accompanied by an ordering of the structure but one in which there is no change in associated water molecules. The transition state thermodynamics suggest a very strained transition state but one where, again, no change in water interactions is detectable.
Fischer, Sabine. "Charakterisierung von exothermen Zersetzungsreaktionen mit thermoanalytischen und numerischen Methoden." Tönning Lübeck Marburg Der Andere Verl, 2008. http://d-nb.info/988248646/04.
Full textBenedek, Christina. "Synthese und Eigenschaften neuartiger, nichtkristallisierbarer Amphiphile als Baustein für biologische Modellmembranen." [S.l. : s.n.], 2000. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB8590236.
Full textHoleman, Teryn A., and Teryn A. Holeman. "Effects of Three Cardiomyopathic-Causing Mutations (D230N, D84N, and E62Q) on the Structure and Flexibility of α-Tropomyosin." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/624101.
Full textZander, Patrik, and Johan Hammarström. "Värmebehandling av segjärn med hög kiselhalt." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Maskinteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-16377.
Full textThe background to this thesis was that Qumex Materialteknik at several occasions had received material of type SS 0725 that had shown deficient heat treatment results. The material, which is relatively new, is a cast iron of type ductile iron and differ against other ductile irons because of its high silicon content. According to EN standard ductile irons are classified by their mechanical properties. A problem then occurs with the new material SS 0725 because of this. The material fulfils the requirements for EN-GJS-500-7 and is therefore in the same classification as a ductile iron with much lower silicon content. Two materials having major differences in chemical composition ending up in the same classification can be problematic. The purpose of this report is to determine impact of high silicon content in ductile iron when heat treated and quench hardened. The experiment included four materials, and the major difference between the materials were their content of copper and silicon. The heat treatment process was performed at three different temperatures and three different treatment times. Afterwards the samples were quenched in oil. The ambition of the quench hardening was to obtain a material structure of 100% martensite. By optical microscopy and hardness measurements the results then were evaluated. An investigation of the phase transformation temperature in the materials was made by using Differential Scanning Calorimetry. The results show that the amount of silicon content has great influence on the temperature for receiving good hardening results. To achieve 100% martensite after quench hardening in materials with low silicon content the temperature needs to be over 840°C. For material with high level of silicon content the temperature for achieving 100% martensite needs to be 900°C and the treatment time should be over 1 h. The relative difference in phase transformation temperature was measured using Differential Scanning Calorimetry. The results of the measurements between the materials with high silicon content and materials with low silicon content was 45°C. This result combined with the analysis of the heat treatment process shows that a major increase of the temperature is needed to heat treat SS 0725.
Hoyle, N. D. "The characterisation of the adsorptive and catalytic properties of supported platinum metal catalysts by methods including differential scanning calorimetry." Thesis, Brunel University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370135.
Full textPöhlmann, Milena. "Thermisch härtende Polymerverbundmaterialien als Basis für neue Befestigungssysteme." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1165492370619-99312.
Full textThe development and introduction of ecological construction methods and the use of sandwich materials make it necessary to develop new fixing systems and technologies. Dealing with the application in concrete and other substrates commercial chemical fixing systems show some disadvantages up to date. Especially the rather long curing time in order to realize the final bond strength, inhomogenities in the composite, the partial use of toxic substances and application limits of such systems in horizontal direction as well as hollow section materials has so far prevented the use of such composites for all-purpose applications. A new chemical fixing system, which consists of hexamethylene tetramine (hexa) cured novolac and inorganic filler, was developed for application in concrete. It is applied by a thermo-curing procedure. The uncatalyzed curable mixture has a high reactivity at temperature between 150-300 °C. Compared with commercial chemical fixing systems, the premixed curable mass has many benefits. First it has a unique storage stability and second, it is free of toxic and volatile substances. Another important aspect is, it is self-foaming. In this study was investigated the overall kinetics of the reaction during the curing process of these polymer composites. An appropriate method for this experiment proved to be the DSC in isothermal and non-isothermal mode and MDSC. This turned out to be a safe quality control technique for these systems. Parallel to the non-isothermal and isothermal DSC conductivity measurements have been performed to determine the end point of the curing reaction
Wampler, Amos. "Resolution of crystalline phases in polymorphic gel-spun ultra-high molecular weight polyethylene fibers using restrained differential scanning calorimetry and x-ray diffraction." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 70 p, 2008. http://proquest.umi.com/pqdweb?did=1597633731&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Full textPisch-Heberle, Sandra. "Untersuchungen zur Stabilisierung von Membranproteinen mit ungewöhnlichen Phospholipiden." [S.l.] : Universität Stuttgart , Fakultät Chemie , Institut für Technische Biochemie, 2000. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB8619088.
Full textChabalenge, Billy, Sachin A. Korde, Adrian L. Kelly, Daniel Neagu, and Anant R. Paradkar. "Understanding Matrix Assisted Continuous Cocrystallisation using Data Mining approach in Quality by Design (QbD)." ACS, 2020. http://hdl.handle.net/10454/18005.
Full textThe present study demonstrates the application of decision tree algorithms to the co-crystallization process. Fifty four (54) batches of carbamazepine–salicylic acid co-crystals embedded in poly(ethylene oxide) were manufactured via hot melt extrusion and characterized by powder X-ray diffraction, differnetial scanning calorimetry, and near-infrared spectroscopy. This dataset was then applied in WEKA, which is an open-sourced machine learning software to study the effect of processing temperature, screw speed, screw configuration, and poly(ethylene oxide) concentration on the percentage of co-crystal conversion. The decision trees obtained provided statistically meaningful and easy-to-interpret rules, demonstrating the potential to use the method to make rational decisions during the development of co-crystallization processes.
Kumar, Prateek. "Heat Capacity and Oxidation Kinetic Studies of Fe-Ti Composite Metal Oxide (ITCMO) using Simultaneous Differential Scanning Calorimetry and Thermogravimetric Analysis." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1502723527531035.
Full textDing, Shu. "Thermodynamic studies on iron-sulfur cluster assembly proteins." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1316472363.
Full textYoung, Gregory Scott. "The application of thermal microscopy, differential scanning calorimetry, and fourier transform infrared microspectroscopy to characterize deterioration and physiochemical change in fibrous Type 1 collagen." Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420072.
Full textAlmutairi, Badriah Saad. "Correlating Melt Dynamics with Glass Topological Phases in Especially Homogenized Equimolar GexAsxS100-2x Glasses using Raman Scattering, Modulated- Differential Scanning Calorimetry and Volumetric Experiments." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1593272974284834.
Full textBlomdahl, Emil. "Synthesis and characterization of novel hybrid organic-inorganic materials." Thesis, KTH, Tillämpad fysikalisk kemi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302288.
Full textThe demand for better and more sustainable material is increasing. More efficient materials will be needed to meet the growing global need. Hybrid organic-inorganic materials are one type of materials that have been of great interest recently, which can be described as a class of materials that mix organic and inorganic components. This thesis focused on hybrid organic-inorganic materials inspired by the classical perovskite crystal structure ABX3, where component A is an organic cation, component B is a divalent metal cation and component X is an anion. Hybrid organic-inorganic materials based on the classical perovskite structure may have various functional properties and may have a broad range of potential applications. Some examples of those properties as well as some and possible applications include good photoconductivity and power conversion efficiency for photovoltaic devices, excellent emission properties for light emitting diodes and tunable dielectric properties for electronic switches and sensors. The physical properties of the hybrid organic-inorganic material are determined by the crystal structure of the material, which in turn will be decided by the choice of components. With the many possible choices for organic and inorganic components, there is an opportunity to synthesize completely new hybrid organic-inorganic compounds that may display new or superior physical properties. Current hybrid organic-inorganic materials based on the perovskite crystal structure mainly use lead as the divalent metal, since it currently gives the best performance. The toxicity of lead is a major drawback for current lead-based hybrid organic-inorganic materials. The possibility to replace lead with another divalent metal has been explored during this project. For this thesis, the organic cation cyclohexylammonium (CHA) has been of focus as the organic component. The aim of this thesis was to design, synthesize and characterize novel hybrid organic-inorganic compounds. The hybrid organic-inorganic compounds CHAZnBr3 and (CHA)2ZnBr4 were synthesized for the first time, to the best of our knowledge, and will be the focus of this thesis. The two new hybrid organic-inorganic compounds were structurally characterized by X-ray Diffraction (XRD) and thermally characterized by Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The first compound, CHAZnBr3, could be determined to be orthorhombic at 298 K. The compound was found to be thermally stable up 490 K, and to undergo a phase transition at 445 K. The second compound, (CHA)2ZnBr4, could not be fully structurally solved at either 100 K or 298 K. The compound was found to be thermally stable up to 490 K, and to undergo a phase transition at 230 K. Further characterization will be needed to better understand the properties of these two compounds and their possible applications.
Craft, Garrett Michael. "Characterization of Nylon-12 in a Novel Additive Manufacturing Technology, and the Rheological and Spectroscopic Analysis of PEG-Starch Matrix Interactions." Scholar Commons, 2018. http://scholarcommons.usf.edu/etd/7137.
Full textGul, Kiymet Gizem. "Thermal Characterization And Kinetic Analyis Of Sara Fractions Of Crude Oils By Tga And Dsc Methods." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613614/index.pdf.
Full textC/min) under air atmosphere. Same gas flow rate and same pressure were applied to all samples. The aim is to determine the kinetic analysis and combustion behavior of crude oils and their fractions and also determining the effect of heating rate on all samples. For all samples two main reaction regions were observed in thermogravimetry (TG), differential thermogravimetry (DTG) and DSC curves due to the oxidative degradation of crude oil components. It was deduced that the free moisture, volatile hydrocarbons were evaporated from the crude oils, light hydrocarbons were burned and fuel was formed in the first reaction region. The second reaction region was the main combustion region where the fuel was burned. From the TGA curves, it was detected that the heavier fraction, resins, lost considerable amounts of their initial mass, approximately 35%, while saturates lost only approximately 3% of their initial mass in the second reaction region. DSC curves of the samples were also examined and observed that as the sample got heavier, the heat of the reaction increased. Saturates, lightest part of the crude oil fractions, gave minimum heat of reaction. As the heating rate increased, shift of peak temperatures to high values and higher reaction regions were observed. The kinetic analysis of crude oils and their fractions were also performed using different kinetic methods. Activation energies (E), mean activation energies (Emean) and Arrhenius constants were found for crude oils and fractions. It was deduced that the resins gave the highest activation energy and Arrhenius constant for both reaction regions. Moreover, it was encountered that heating rate has no effect on activation energies.
Smith, Beverly. "Investigating Thermal Transformations of Ligand-Stabilized Gold Nanoparticles: Influence of the Structural Attributes of the Nanoparticle and Its Environment on Thermal Stability." Thesis, University of Oregon, 2015. http://hdl.handle.net/1794/19259.
Full text10000-01-01
Oliveira, Levi Ezequiel de. "Análise térmica dos biodieseis obtidos por rota enzimática e suas respectivas matérias-primas." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/97/97136/tde-03102012-121140/.
Full textMost of all energy consumed worldwide comes from oil, coal and natural gas (87% of global energy production). However, these non-renewable resources are expected to exhaust in the near future. Moreover, they are polluters, affecting the environment, prompting the company to seek alternative sources to mitigate these problems. Biodiesel as alternative fuel, that began to be studied in 1937 and today has proved an efficient and non-polluting alternative to the use of mineral diesel. The present study was performed with babassu, palm and tallow biodiesel obtained using enzymatic catalysts. This route has been investigated by several researchers in the country, and has shown that the use of enzyme as catalyst minimizes the problems related to the final stages of purification of biodiesel, it reduces the occurrence of undesirable reactions of saponification and allows for simplification and cost reduction processes by reducing the number of associated operations. To be a substitute, biodiesel must fit in standards, in the case of Brazil, the resolution No. 42 of the ANP (National Agency of Petroleum, Natural Gas and Biofuels), 2004. Also this biofuel must posses qualities thet might allow the replacement. This work aims to realize the thermal studies using thermogravimetry (TG) and Differential Scanning Calorimetry (DSC) of babassu, palm and tallow biodiesel obtained by enzymatic route and also their raw materials. With the results of TG in an inert atmosphere, it was possible to analyze the volatility of biodieseis, and also check your guidelines on the parameter of the distillation of Resolution No. 42 of the Brazilian Petroleum Agency (ANP). The TG analysis of biodiesel in oxidative atmosphere turns possible to study their thermo-oxidative stabilities. Also, it was performed a kinetic study of the TG curves, seeking the value of activation energy of the first steps of each curve, using the mathematical model Ozawa. The kinetic study of the TG curves in nitrogen atmosphere showed that the activation energy and temperature of the beginning of degradation have a direct relationship.
Lans, Alexa Michelle. "Evaluation of Water Sorption and Thermal Properties of Galacto-oligosaccharides, and Application in Glassy Confections." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1460764786.
Full textCarvalho, Tânia Isabel da Silva. "Development of ion jelly thin films for electrochemical devices." Doctoral thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10874.
Full textIonic liquids (ILs) are promising materials which have been used in a wide range of applications. However, their major limitation is their physical state. In order to address this challenge, a self-supported IL-based material was developed by combining gelatine with an IL, originating a quasi-solid material named Ion Jelly (IJ). This is a light flexible material, dimensionally stable, with promising properties to develop safe and highly conductive electrolytes. This thesis is focused on the characterization of IJ films based on different ILs. The conductive mechanisms of IJ materials were studied using dielectric relaxation spectroscopy (DRS) in the frequency range 10-1−106 Hz. The study was complemented by differential scanning calorimetry (DSC) and pulsed field gradient nuclear magnetic resonance (PFG NMR) spectroscopy. A glass transition was detected by DSC for all materials allowing to classify them as glass formers. From dielectric measurements, transport properties such as mobility and diffusion coefficients were extracted. Moreover, it was found that the diffusion coefficients and mobility are similar for the IL and IJ, especially for the IL EMIMDCA. Since for BMIMDCA, those properties significantly change upon hydration, the influence of water content [0.4 - 30% (w/w)] was also studied for the ILs. In particular for BMPyrDCA with 30% water, it was analyzed the reorientational polarization by the complex permittivity and electric modulus, from which three different processes were identified: a secondary relaxation with Arrhenian temperature dependence, the process that is believed to be behind the dynamic glass transition and the mobility of charge carriers. An application of the IJs was successfully explored with a chemoresistive gas sensor made up by different IJs as active layer, which is an electronic nose formed by an array of such sensors. The performance of this e-nose revealed its ability to correctly detect eight common volatile solvents.
Chbeir, Ralph. "Correlating Melt Dynamics with Topological Phases of Homogeneous Chalcogenide- and Modified Oxide- Glasses Using Raman Scattering, Infra-Red Spectroscopy, Modulated-Differential Scanning Calorimetry and Volumetric Experiments." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1573224465185235.
Full textGibson, Irish Alcalen. "Applications of diffuse reflectance near-infrared spectroscopy and cure kinetics study by differential scanning calorimetry to selected thermosetting polymer-based systems of interest in the aviation industry." Diss., Wichita State University, 2012. http://hdl.handle.net/10057/5357.
Full textThesis (Ph.D.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Chemistry
Saffarini, Ghassan. "X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and density study of ternary chalcogenide glasses based on Ge-Se and Ge-S." Thesis, Brunel University, 1991. http://bura.brunel.ac.uk/handle/2438/7396.
Full textVincent, Matthew Ryan. "Crystallization and Melting Studies of Poly(ε-caprolactone) and Poly(ethylene oxide) using Flash™ Differential Scanning Calorimetry and Preparation and Characterization of Poly(δ-valerolactone) Fractions." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/101668.
Full textDoctor of Philosophy
Oghide, Godwin O. "Miscibility studies of poly (methyl acrylate) poly (vinyl acetate) and poly (vinyl acetate)/ poly (vinylidene fluoride) blends using differential scanning calorimetry and fourier transform infra red spectroscopy." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 1985. http://digitalcommons.auctr.edu/dissertations/3294.
Full textGundogar, Sati Asli. "Thermal Characterization And Kinetics Of Crude Oils By Tga And Dsc Methods." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611502/index.pdf.
Full textC/min) and air is used for combustion and nitrogen for pyrolysis experiments. In combustion experiments, TGA and DSC techniques indicate that the combustion process of crude oils studied is composed of two main reaction regions. These are low-temperature (LTO) and high-temperature oxidation (HTO) regions. In LTO, huge mass loss occurs (from 69 to 87 %) due to high amount of free moisture and volatile hydrocarbons contained in oil samples. Combustion reactions continue up to 900 K. On DSC curves, two exothermic regions of oxidation regimes are detected. Comparing TG/DTG and DSC curves, it can be understood that the mass loss under combustion is accompanied by exothermic peaks because of the oxidative degradation of crude oil components. As in combustion, two distinct reaction regions are revealed under pyrolysis for all samples. The first region indicates distillation and the second one is due to thermal cracking reactions occur at high temperatures and completed up to 840 K. As expected, lighter crude oils have relatively higher amounts of mass loss in distillation region as compared to heavier ones. Besides, residue amount and burn-out temperatures are higher for heavier oils with higher asphaltene content in cracking region. DSC curves for both reactions show endothermic effects. In combustion and pyrolysis experiments, it is noticed that higher heating rates are resulted in higher reaction regions. Distinguishing peaks of samples shift to higher temperatures with an increase in heating rate. Heat of reaction amount under DSC curves is related to asphaltene content and &
#730
API gravity of crude oils. It is deduced that, when &
#730
API gravity of crude oils decreases, the heat value of this reaction increases. The kinetic parameters are evaluated by different kinetic models and mean activation energies (Em) of samples are obtained. At the end, a correlation is established between Em and &
#730
API gravity of oil samples. It is concluded that heavier oils have higher activation energy and Arrhenius constant values for each reaction region. Besides, it is proved that the activation energy is mostly insensitive to the heating rate.
Ertunc, Goker. "Development Of A Software For Determination Of Kinetic Parameters In Thermal Analysis." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613624/index.pdf.
Full textHong, Jung Ki. "Effect of Cellulose Nanocrystals on the Rheology, Curing Behavior, and Fracture Performance of Phenol-Formaldehyde Resol Resin." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/46189.
Full textMaster of Science
BHUYAN, MOHAMMAD SHAHAJAHAN KABIR. "Further Applications of Reactive In-Mold Coating (IMC): Effect of Inhibitor and Carbon Nano-Particles." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1531178248132272.
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