Dissertations / Theses on the topic 'Calorimetry'

Orientador: Jose de Alencar Simoni
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Esse trabalho consiste na utilização de um calorímetro isoperibólico em laboratório didático de química no nível superior, para se estudar aspectos mais amplos de alguns processos, que não os energéticos. Como se sabe, o calorímetro é o principal instrumento da primeira lei da termodinâmica e, como tal, presta-se, normalmente, para se obter a variação de energia de fenômenos físicos e químicos como entalpias de dissolução, combustão, neutralização, etc. Nesse projeto, utilizou-se esse instrumento em estudos da cinética de reações químicas, determinação de entalpias de vaporização, entalpias de reações eletroquímicas e estudos de reações oscilantes. O calorímetro utilizado é do tipo isoperibólico e já se encontra em operação no laboratório de Físico-Química do Instituto de Química da Unicamp há um longo tempo. Estudou-se a cinética da reação entre MnO4 e C2O4 em meio ácido, sendo observado que a reação e autocatalisada por Mn. O valor da constante cinética k = 10,4 L mol s determinado por essa técnica mostrou-se concordante com o valor obtido por espectrofotometria k =10,6 L mol s. Também foi estudada a cinética da reação de decomposição de H2O2 por I e o resultado mostrou uma dependência de primeira ordem em relação ao H2O2 e um valor de constante de velocidade k = 6,64 10 s concordante com o da literatura, obtido por outra técnica. Num outro estudo, determinou-se a entalpia da reação eletroquímica de uma solução aquosa de KI, obtendo-se o valor de DH = 247 kJ mol, valor esse, concordante com o da literatura que e de 245 kJ mol. Também foi realizada a reação eletroquímica de uma solução aquosa de sulfato de cobre utilizando-se eletrodos de cobre; os resultados permitiram evidenciar a validade de lei de Hess. Outro experimento observado foi o de reações oscilantes do tipo Belousov-Zhabotinsky. O estudo mostrou ser possivel explorar essa reação de uma forma didática bastante interessante. No entanto, algumas etapas da reação mostraram resultados de difícil acesso e pouca reprodutibilidade. Também foi explorado nesse projeto o uso da primeira lei (calorimetria) e da segunda lei (medidas de pressão de vapor) na determinação da entalpia de vaporização de alguns líquidos como água e etanol. Os resultados mostram que a utilização concomitante dessas duas técnicas leva a resultados concordantes entre si, que permitem ao aluno observar a consistência interna entre a primeira e a segunda lei da termodinâmica
Abstract: This work consists of utilizing an isoperibol calorimeter in educational laboratories of the chemistry college undergraduate course to study unusual aspects of some processes, in addiction to the energetic. As you know, the calorimeter is the main instrument of the first thermodynamic law and, normally, is used to obtain the variation of energy in physical and chemical phenomenon, such as enthalpies of dissolution, combustion, neutralization and other reactions. In this project, the calorimeter was used to study the kinetics of chemical reactions, determining the enthalpies of vaporization, the enthalpies of electrochemical reactions and oscillatory reactions. The instrument used is an isoperibol calorimeter and it has already been in use in the Physical-Chemistry Laboratory of the Unicamp Chemistry Institute for a long time. The study of the kinetic of reactions between MnO4 and C2O4 inside an acid environment showed that the reaction is autocatalyzed by Mn. Through this technique, it was possible to determinate that k = 10,4 L mol s and this value is almost the same obtained by spectrophotometry k = 10,6 L mol s. The kinetic of a decomposition reaction was studied also, and the result showed a dependency of the first order in relation to H2O2 and a value of velocity's constant k = 6,64 10 s concordant with the literature that was obtained through another technique. In another study, the enthalpy of an electrochemical reaction of a wet solution of KI was determinate in DH = 247 kJ mol, and this is concordant with the literature, DH = 245 kJ mol. Another reaction studied was the electrochemical reaction of a wet solution of copper sulfate using copper electrodes, and the results showed evidence, giving validity to the Hess law. Another experiment studied oscillatory reactions of the Belousov-Zhabotinsky type and showed it possible to explore this reaction in a very interesting educational way. In general, some reaction Ls steps showed results of hard access and low reproduction. Also studied in this project was the use of the first law (calorimetry) and the second law (measures of vapor pressure) in determining the vaporization enthalpy of some liquids as water and ethanol. The results show that the use of these two techniques, at the same time, lead to concordant results that permit the student to observe the relation between the first and the second thermodynamic laws
Mestrado
Físico-Química
Mestre em Química

Orientador: Maria Alvina Krähenbühl
Dissertação (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

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.
Includes bibliographical references (leaf 52).
Isothermal titration calorimetry is a technique used to measure the enthalpy change associated with a molecular binding interaction. From these data, the binding constant for the reaction can be determined. In the scope of a larger project to design a high sensitivity instrument for collecting such data, the current methods in isothermal titration calorimetry were investigated. Further calorimetric experience was acquired by designing a large scale calorimetric device. Dilution reactions with dimethyl sulfoxide and water were conducted to measure the excess enthalpy of binding. The inaccuracy of these measurements necessitated the more careful design of an isoperibol calorimeter. This calorimeter was modeled was an arrangement of coupled thermal masses and capacitances in order to fully understand its transient response to a thermal input. Dilution reactions and a neutralization reaction with HCl and NH40H were performed on the system and the results were used to make recommendations for the design of the future high sensitivity device.
by Ovid Charles Amadi.
S.B.

In the experiment E683 at Fermi National Accelerator Lab (FNAL) in Batavia, Illinois, a modular, high-energy sampling calorimeter was the basis of the detector system. In order to monitor each of the 528 modules of the calorimeter, an embedded LED was flashed directly into each of the 528 PMT tubes (which normally pick up the light from the sampling modules of the calorimeter) and their responses were recorded. The purpose of this investigation was to observe, study, and possibly make corrections for any fluctuations in the PMT response to the LED signals. Also, as a check, the PMT data was analyzed to see if any LED fluctuations were correlated with any fluctuations in the calorimeter module data coming from particles produced when targets were exposed to accelerator beam particles. These studies were done using a VAXstation model 4000/60, and the database and graphics components (called 'N-tuples' and `PAW' respectively) of a High Energy Physics math package called 'CERNLIB'. By putting the analyzed data into n-tuple files, many different modelings of the same data could be checked more efficiently. The study found that the LED system was useful for detecting and correcting for signal degradation due to calamp failure and these corrections were put in the E683 analysis package. It was also found that long term LED response signal fluctuations were not completely explained, but that there was no correlation with beam induced calorimeter response signal fluctuations.
Department of Physics and Astronomy

MINOS is a long-baseline neutrino oscillation experiment. A neutrino beam is created at the Fermi National Accelerator Laboratory in Illinois and fired down through the Earth. Measurements of the energy spectra and composition of the neutrino beam are made both at the source using the Near detector and 735 km away at the Soudan Underground Laboratory in Minnesota using the Far detector. By comparing the spectrum and flavour composition of the neutrino beam between the two detectors neutrino oscillations can be observed. Such a comparison depends on the accuracy of the relative calorimetric energy scale. This thesis details a precise measurement of the calorimetric energy scale of the MINOS Far detector and Calibration detector using stopping muons with a new "track window" technique. These measurements are used to perform the relative calibration between the two detectors. This calibration has been accomplished to 1.7% in data and to significantly better than 2% in the Monte Carlo simulation, thus achieving the MINOS relative calibration target of 2%. A number of cross-checks have been performed to ensure the robustness of the calorimetric energy scale measurements. At the Calibration detector the test-beam energy between run periods is found to be consistent with the detector response to better than 2% after the relative calibration is applied. The muon energy loss in the MINOS detectors determined from Bethe-Bloch predictions, data and Monte Carlo are compared and understood. To estimate the systematic error on the measurement of the neutrino oscillation parameters caused by a relative miscalibration a study is performed. A 2% relative miscalibration is shown to cause a 0.6% bias in the values of Δm² and sin²(2θ).

The ATLAS experiment -- situated at the Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) in Geneva -- is on schedule to take its first collision data in 2009. Physics topics include finding the Higgs boson, heavy quark physics, and looking for extensions of the standard model such as supersymmetry. Upon acceptance of an event by the level 1 trigger, data is read out from the liquid argon calorimeters using multi-mode optical fibers. In total, 58 cables were installed, corresponding to 232 12-fiber ribbons or 2784 individual fibers. The cables, about one hundred meters in length, were installed between the main ATLAS cavern and the counting room in the USA15 cavern. Patch cables were spliced onto the ribbons and the fiber attenuation was measured. For 1296 fiber pairs in 54 cables, the average attenuation was 0.69 dB. Only five fibers were found to have losses exceeding 4 dB, resulting in a failure rate of less than 2 per mil. In the ATLAS liquid argon barrel presampler, short circuits consisting of small pieces of dust, metal, etc. can be burned away in situ by discharging a capacitor over the high voltage lines. In a burning campaign in November 2006, seventeen existing short circuits were successfully removed. An investigation on how to implement saturation effects in liquid argon due to high ionization densities resulted into the implementation of the effect in the ATLAS Monte Carlo code, improving agreement with beam test data. The timing structure of hadronic showers was investigated using a Geant4 Monte Carlo. The expected behavior as described in the literature was reproduced, with the exception that some sets of physics models gave unphysical gamma energies from nuclear neutron capture. An ATLAS Combined Beam Test was conducted in the summer/fall of 2004 in the CERN H8 area, containing a whole slice of the ATLAS detectors in the central barrel region. The controlled single-particle environment allows the validation of Monte Carlo code and calibration. A method for calibrating the response of a segmented calorimeter to hadrons was developed. The ansatz is that information on longitudinal shower fluctuations gained from a principal component analysis of the layer energy depositions can improve energy resolution by correcting for hadronic invisible energy and dead material losses: projections along the eigenvectors of the correlation matrix are used as input for the calibration. The technique was used to reconstruct the energy of pions impinging on the ATLAS calorimeters during the 2004 Combined Beam Test. Simulated Monte Carlo events were used to derive corrections for invisible energy lost in nuclear reactions and in dead material in front and in between the calorimeters.  For pion beams with energies between 20 and 180 GeV, the particle energy was reconstructed within 3% and the resolution was improved by about 20%. As a comparison, a simple iterative scheme with a single e/π factor and dead material corrections was devised, giving similar performance.

Calorimeter has been an essential element of High Energy Physics Experiment for decades. As beam energies of hadron colliders reached the multi-TeV range, hermeticity of the calorimetric system became a high priority issue. Additional requirements arose from increased luminosity. The Forward Calorimeter (covering rapidity η >3) must to provide high quality measurements of hadronic jets (energy and position) at extremely high rate and at the same time withstand a harsh radiation environment. The Liquid Argon Tube Forward Calorimeter was developed at the University of Arizona to fulfill those requirements. Prototypes of the electromagnetic section (15X₀, later 25X₀) were tested at BNL and CERN secondary beams in 1993 and 1995. Data acquired in those tests allowed us to study such vital parameters of the calorimeter as response uniformity, energy and position resolution. An energy range from 2 GeV to 200 GeV and angles from 0.6° to 5.6° were covered. Observed results (together with extensive Monte-Carlo simulation studies of the Forward Region) allowed the Liquid Argon Tube Calorimeter to be chosen among several competing designs as the Baseline for the Forward Calorimeter of the ATLAS multi-purpose detector at the LHC (CERN).

Orientador: Claudio Airoldi
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Mestrado
Quimica Inorganica
Mestre em Química

This thesis is centred on the use of an isothermal titration microcalori-meter which can measure heat changes of the order of a few microcalories. The calorimeter provides a rapid and convenient method, incorporating a thermodynamic analysis, for estimating enthalpic pairwise interaction parameters, hjj, for solute-j in aqueous solution. Estimates of hjj for three solutes; urea, monoethylurea and hexamethylenetetramine are reported. Comparisons with published estimates of hjj show good agreement, and confirm the importance of the new technology in calorimetry. The critical micellar concentrations (cmc's) of a series of l-alkyl-4-alkylpyridinium halide and bisquaternary ammonium bromide surfactants are reported, using q, heat change on injection, as the reporter. The standard enthalpy of micelle formation is also obtained, directly, from titration experiments. An equation is derived for the standard Gibbs energy of micelle formation, for these compounds. Thus, the standard entropy is calculated and the driving force (enthalpy or entropy) for micellisation, of these surfactants, is identified. Injection of small aliquots of fusogenic agents (the dianions of dipicolinic acid and sodium sulphate) into aqueous solutions of dioctadecyldimethyl-ammonium bromide (DOAB) vesicles is endothermic at 50 Celsius. For solutions containing greater than equimolar ratios of DOAB and fusogenic agent, the injection process is effectively athermal. The patterns of enthalpy change are attributed to vesicle-dianion interaction (exothermic) and headgroup dehydration (endothermic). Other effects such as the presence of buffer and the interaction of DOAB with halide monoanions are also discussed. Binding of the substrate, chloramphenicol (CM), to the enzyme, chloramphenicol acetyltransferase (CAT), is exothermic. Calorimetric measurements of a series of injections of CM into CAT, and subsequent analysis, yield the binding constant, number of binding sites per macromolecule (enzyme) and the standard enthalpy of binding for the interaction. These three parameters are presented, together with the standard entropy and standard Gibbs energy of binding.

This thesis describes the optimisation of the calorimeter design for collider experiments at the future Compact Linear Collider (CLIC) and the International Linear Collider (ILC). The detector design of these experiments is built around high-granularity Particle Flow Calorimetry that, in contrast to traditional calorimetry, uses the energy measurements for charged particles from the tracking detectors. This can only be realised if calorimetric energy deposits from charged particles can be separated from those of neutral particles. This is made possible with fine granularity calorimeters and sophisticated pattern recognition software, which is provided by the PandoraPFA algorithm. This thesis presents results on Particle Flow calorimetry performance for a number of detector configurations. To obtain these results a new calibration procedure was developed and applied to the detector simulation and reconstruction to ensure optimal performance was achieved for each detector configuration considered. This thesis also describes the development of a software compensation technique that vastly improves the intrinsic energy resolution of a Particle Flow Calorimetry detector. This technique is implemented within the PandoraPFA framework and demonstrates the gains that can be made by fully exploiting the information provided by the fine granularity calorimeters envisaged at a future linear collider. A study of the sensitivity of the CLIC experiment to anomalous gauge couplings that {affect} vector boson scattering processes is presented. These anomalous couplings provide insight into possible beyond standard model physics. This study, which utilises the excellent jet energy resolution from Particle Flow Calorimetry, was performed at centre-of-mass energies of 1.4 TeV and 3 TeV with integrated luminosities of 1.5$\text{ab}^{-1}$ and 2$\text{ab}^{-1}$ respectively. The precision achievable at CLIC is shown to be approximately one to two orders of magnitude better than that currently offered by the LHC. In addition, a study into various technology options for the CLIC vertex detector is described.

O aporte térmico, ou imposição de calor, é uma das características com grande importância nos processos de soldagem, pois ela está diretamente relacionada com as propriedades mecânicas e as transformações metalúrgicas da junta soldada. Neste sentido, este trabalho propõe o projeto, a construção e a validação de um calorímetro com uma vazão contínua de água para avaliação do aporte térmico e da eficiência térmica em processos de soldagem a arco elétrico que seja de baixo custo, adaptável aos diferentes processos de soldagem, de simples operação e fácil movimentação. Foram realizados experimentos com três processos, sendo eles: soldagem a arco com gás de proteção e eletrodo consumível (GMAW – Gas Metal Arc Welding), soldagem a arco com eletrodo não consumível e gás de proteção (GTAW – Gas Tungsten Arc Welding) e soldagem ao arco submerso (SAW – Submerged Arc Welding). As atividades realizadas visam identificar o efeito sobre a eficiência térmica devido à variação de alguns dos parâmetros de soldagem bem como identificar características intrínsecas do calorímetro construído. Para o processo de soldagem GMAW verificou-se um rendimento médio do arco de 72,82%, com uma eficiência média de 71,10% especificamente para o processo GMAW com transferência metálica goticular e de 76,26% para transferência metálica por curto-circuito. O processo de soldagem GTAW apresentou uma eficiência térmica média de 68,44% e para o processo SAW foi observado um rendimento do arco de 91,05%. Os resultados obtidos se mostraram coerentes quando comparados aos valores reportados anteriormente por outros autores e também apresentaram uma boa repetitividade, sendo de 4,5% a maior diferença observada entre cordões de solda de um mesmo experimento.
Heat input is an important welding process characteristic since it is directly related to the mechanical properties and metallurgical transformations of the welded joint. This paper aims to present the project, construction and validation of a calorimeter with continuous water flow to evaluate the heat input and the thermal efficiency of arc welding processes. The proposed calorimeter shall have a low cost, versatile, easy to handle and to operate. Experiments were carried out with gas metal arc welding (GMAW), gas tungsten arc welding (GTAW) and submerged arc welding (SAW). These activities aimed to identify the effect that changes of certain welding parameters perform on the thermal efficiency and to identify intrinsic characteristics of the proposed calorimeter. For GMAW processes it was obtained a global thermal efficiency of 72.82%. For this process, the results were different according to the metal transfer: 71.10% for GMAW with spray transfer and 76.26% for GMAW with short circuit transfer. The average thermal efficiency obtained for the GTAW was of 68.44% and for the SAW process was of 91.05%. The experiments results showed to be consistent when compared to previously reported values by other authors and also showed good repeatability, where the large difference observed between weldments of the same experiment was of 4.5%.

Experiment 683, at Fermi National Accelerator Laboratory's Wide Band Photon Laboratory, is designed to study photon-hadron collisions at energies up to ~s = 27 GeV. The Wide Band Photon Lab currently the highest energy photon beam in the world. Several processes are to be studied. One such process in the quantum electrodynamic (QED) Compton effect. This paper is concerned with the design and construction of a small electromagnetic calorimeter (with embedded proportional wire chambers) to be used to aid in the study of the QED Compton effect. A theoretical description of the QED Compton effect is given. Basic principles of calorimetry, as it pertains to high energy physics, are discussed. Tests of the components used for construction of this device is discussed and results reviewed. The components include wavelength shifter, scintillator, photomultiplier tubes, and photomultiplier tube bases. Muon testing of this device is discussed also.
Department of Physics and Astronomy

Pharmaceuticals are formulated to be stable products and hence studying their stability using conventional techniques can be difficult and time consuming. Isothermal calorimetry has the potential to study stability of pharmaceuticals, as it is sensitive enough to detect extremely small heat flows associated with change (chemical or physical). Its use in the pharmaceutical arena has not been widespread because of the difficulties associated with analysing data recorded from complex processes, since heat is ubiquitous. The work presented in this thesis demonstrates the applicability of isothermal calorimetry in the stability assessment of pharmaceutical model systems. Calorimetric data recorded for complex processes were analysed based on kinetic modelling. Initial studies involved the degradation of simple single-step processes '(hydrolysis of aspirin), followed by model systems with increasing complexity. Degradation involving parallel processes - binary mixtures of para bens was studied. Using kinetic models, rate constants and reaction enthalpies were determined for individual processes. Data recorded for consecutive reactions, commonly encountered in pharmaceuticals can be difficult to analyse if exact mechanisms are unknown. The use of chemometric techniques to analyse calorimetric data recorded for complex processes offers great potential when reaction mechanisms are unknown. The two-step consecutive reaction of potassium hydroxylamine disulfonate was successfully analysed for reaction parameters using kinetic-based models and chemometric analysis. ' Significant proportions of degradation in pharmaceuticals proceed at a slow rate and can pose difficulty in their assessment. Minimum desirable reaction parameters required to successfully analyse calorimetric data for slow reactions were generated and its use in designing calorimetric experiments were demonstrated. Finally the use of IC in the preformulation stages of drug development are emphasised, particularly its role in purity determination of impure aspirin and drug excipient compatibility. Compatibility between aspirin and magnesium stearate was investigated using IC and reaction parameters obtained were compared to those obtained using conventional chromatographic techniques.

The American Society of Civil Engineers’ (ASCE’s) “2013 Report Card for America’s Infrastructure” estimated that “32% of America’s major roads are in poor or mediocre condition.” An estimated $100 billion dollars are needed to maintain that condition, and an additional $79 billion is needed to improve the quality of American roadways to an acceptable level. In many regions around the US, the service lives of concrete pavements are limited by the damage caused by freezing and thawing of pore solution inside the pavements. Alkali-activated slags (AAS) are produced from ground granulated blast furnace slag (GGBFS), a byproduct of iron production, and exhibit cementitious properties. AAS concretes have been shown to have improved corrosion and freeze/thaw resistance compared to traditional cementbased concretes. A Guarded Longitudinal Comparative Calorimeter (GLCC) was used to determine when the freezing and thawing of internal water occurs in three AAS mortars using solutions of NaOH, Na2CO3, or waterglass compared to a control Ordinary Portland Cement (OPC) mortar. AAS mortars using NaOH and Na2CO3 showed comparable thermal properties to the OPC mortar using the GLCC, and the AAS mortar using waterglass was shown to have higher heat capacity compared to the other AAS mixes. The compressive strengths varied by the alkaline solution used, with AAS with Na2CO3 showing inferior compressive strength to OPC, AAS with NaOH showing similar compressive strength to OPC, and AAS with waterglass showing superior compressive strength to OPC, but poor workability. A computer model of the GLCC testing procedure was created and showed good agreement with the experimental data. The GLCC model can be modified to approximate the results of the GLCC using a wider range of materials and internal solutions, like PCMs.

The International Linear Collider (ILC) is intended to be a new high precision electron-positron collider operating at the TeV scale. The studies detailed within this thesis deal primarily with the development of Monolithic Active Pixel Sensors (MAPS) which could be used as the sensitive component of an ILC Electromagnetic Calorimeter (ECAL). These include simulations of a MAPS ECAL to investigate pixel saturation as a function of reset time, and energy resolution for single electrons. The energy resolutionσ (E)/E was found to be (0.1147±0.0004)/E\(^{1/2}\)(GeV\(^{1/2}\)). The remaining studies describe part of the calibration process for prototype MAPS sensors and how those sensors were used to characterise the response of MAPS pixels to a 120 GeV pion beam. This resulted in a measurement of the MIP (Minimum Ionising Particle) efficiency of MAPS pixels of 75% to 95% with some variation due to the properties of the epitaxial layer.

LHCb is one of the four large experiments of the Large Hadron Collider (LHC) based at CERN. The LHCb experiment is taking data at its nominal design luminosity. However, in order to distinguish among models of new physics, higher luminosity is needed. So the LHCb collaboration intends to upgrade the detector during the planned long LHC shutdown in 2019 in order to be able to operate at a luminosity about 10 times the nominal one. The objective the present thesis is the development of an integrated solution for the analog signal processing in the electronic and hadronic calorimeters of the LHCb. The analogue signal processing will be performed by a shaper ASIC in the calorimeters Front End (FE) boards. The signal pulse from a photomultiplier tube is clipped at its base and, then, is transmitted through a 12m 50Ω coaxial cable to the FE board located in the crates at the calorimeter platform. In order to reduce the PMT ageing after the increase in luminosity, the gain has to be decreased by a factor 5 with respect to the present operation in order to keep the same average current. Therefore, the preamplifier input noise must be decreased accordingly so that the total input referred noise voltage is smaller than 1nV/√Hz. Consequently, a 50Ω termination resistor is not acceptable. The main requirements for the analogue FE of the calorimeter system include a cali- bration of 4fC/2.5MeV per ADC count; a dynamic range of 12 bits; noise lower than 1 ADC cnt (ENC < 4 fC); and a spill-over residue level ±1% a linearity: < 1%. The implementation of the ASIC includes: four analog channels with programmable values to control the key parameters and compensate for process variations; a dedicated Delay Locked Loop (DLL) to synchronize each channel signal phase and a digital interface using SPI protocol. The analog channel is designed with an input amplifier that includes an electronically cooled termination input stage. A passive line termination would induce too large a noise and is avoided. Afterwards an alternated switched differential signal paths scheme permits the integration of the signal with no dead time between consecutive events. Each path includes a pole-zero filter in order to compensate for cable effects, a switched integrator with capacitive feedback, a Track-and-Hold for a 12-bit ADC and a MUX to select the correct sub-channel output signal. A fully differential signal processing is adopted in order to minimize the impact of common mode noise, which is important in a switched system. Each analog channel includes a delay line based on a DLL so the user can set a delay to compensate the delay introduced by PMT voltage settings, cable lengths or particle time of flight from the interaction point to the calorimeter cells. The DLL is adjusted by means of two control voltages to ensure that systematic process or environmental variations will not affect the channel time tuning. The radiation hardness expected from the selected technology (0.35µm AMS SiGe BiCMOS) is enough, but design techniques are used to ensure being able to tolerate SEUs, SETs and SELs. The design has been checked at different tests of a total of 30 pieces of the final pro- totype: at the laboratory using a signal obtained with a scope, with electron beams and ECAL channels in a dedicated facility at CERN, and its radiation hardness at Centre de Resources du Cyclotron at Louvain la Neuve. Dedicated boards were developed and the results are positive.
L’LHCb és un dels quatre grans experiments del Gran Col·lisionador d’Hadrons al CERN. En aquest moment, l’experiment LHCb ja ha profunditzat en el seu programa de presa de dades, però, per tal de realitzar estudis destinats a distingir entre models de nova física es pretén actualitzar el detector el 2019 per tal d’operar amb una lluminositat uns deu cops superior a l’actual. L’objectiu de la present Tesi és el desenvolupament d’una solució integrada pel processat del senyal analògic en la actualització i millora de l’electrònica del Calorímetre, sub-detector de l’LHCb. Aquest processat es durà a terme a les plaques d’electrònica front-end (FE) mitjançant un ASIC que rep polsos que venen de tubs fotomultiplicadors (PM) a través de 12 m de cable coaxial de 50 Ohms. Els principals requeriments del FE analògic del Calorímetre inclouen una calibració de 4.5fc/2.5MeV per compte d’ADC, un rang dinàmic de 12 bits, un soroll menor a 1 compte d’ADC, un nivell de cua residual menor que 1% i una desviació de la linearitat menor que 1%. La implementació de l’ASIC inclou quatre canals analògics amb valors programables, una línia de retard (DLL) i una interfase digital utilitzant protocol SPI. El canal analògic disposa d’un amplificador d’entrada que inclou una terminació de línia activa. Desprès, un sistema de dos subcanals diferencials commutats permet la integració del senyal sense temps morts entre esdeveniments consecutius. Cada subcanal inclou un filtre de pol-zero, un integrador commutat, un Track-and-Hold i un multiplexor. Finalment, la DLL proporciona els senyals de rellotge per sincronitzar els canals. La pròpia resistència a la radiació que assegura el fet de fer servir la tecnologia escollida (AMS 0.35um BICMOS) i l’ús de tècniques específiques permet una tolerància del circuit integrat a SEUs, SETs i SELs, als nivells esperats al detector. El disseny ha estat verificat en diferents proves per un total de 30 prototips de la versió final del xip: primer, al laboratori, utilitzant un senyal obtingut amb un oscil·loscopi al detector; amb feixos d’electrons i canals del detector, a zones dedicades al CERN; i, la resistència a la radiació s’ha verificat al CRC a Louvain la Neuve, Bèlgica.

Orientador: Claudio Airoldi
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: A quitosana sofreu uma série de modificações químicas para se obter novos derivados, que contém centros básicos de nitrogênio, oxigênio e enxofre. Foram utilizados nas modificações os anidridos succínico, ftálico e malêico, com e sem a utilização de solvente, com reação posterior com etilenodiamina ou dietilenotriamina. Também foram utilizados nas modificações etilenossulfeto e acetilacetona, bem como a reticulação da quitosana com os agentes glutaraldeído, tripolifosfato de sódio e epicloridrina, na forma de pó ou esferas. Todos os materiais foram caracterizados através de análise elementar, espectroscopia na região do infravermelho, ressonância magnética nuclear de carbono 13, difração de raios x e termogravimetria. Estas matrizes foram utilizadas na sorção de cátions metálicos de solução aquosa e determinados os parâmetros termodinâmicos dessas interações. A quitosana não modificada apresenta a seguinte ordem de sorção dos cátions metálicos em sua superfície: Cu > Cd > Ni > Pb > Co > Zn. Esta seqüência reflete uma concordância com a série de Irving-Williams, que demonstra uma estabilidade de formação desses complexos metálicos. O cobre apresentou excelentes valores de sorção, sendo o maior valor encontrado para o material QMN, quitosana modificada com anidrido malêico e etilenodiamina, sendo de 2,36 ± 0,05 mmol g, refletindo a melhora na capacidade de sorção através dessa modificação química, já que o valor de sorção de cobre na quitosana não modificada foi de 1,39 ± 0,04 mmol g. A quitosana QES, modificada com etilenossulfeto, apresentou boas capacidades de sorver chumbo e cádmio de solução aquosa, sendo essas capacidades de 1,80 ± 0,01 e 1,95 ± 0,02 mmol g, respectivamente. Também foram obtidas esferas de quitosana, EQ e QTPP, que apresentaram uma capacidade de sorção superior ao pó de quitosana não modificada, além disso, as esferas mostraram uma maior estabilidade e facilidade quanto à manipulação. Todos os dados de sorção ajustaram-se bem ao modelo de Langmuir. Os valores de energia livre mostram a espontaneidade de todos os sistemas, os quais apresentaram valores negativos de entropia para alguns casos. A variação de entalpia resultante para a interação entre o cobre e a quitosana modificada QMN apresentou-se como o maior valor para este metal, sendo de -51,64±0,03 kJ mol, bem como a quitosana QES que apresentou os valores -52,37±0,01 e -63,52±0,02 kJ mol para as interações com chumbo e cádmio, respectivamente.
Abstract: Chitosan was submitted to a series of chemical modifications to obtain new derivatives that contains basic centers nitrogen, oxygen and sulfur. They were used in the modifications succinic, phthalic and maleic anhydrides, with and without solvent, with subsequent reaction with ethylenediamine or diethylenetriamine. Ethylene sulfide and acetylacetone were also used in the modifications, as well as the crosslinking of the chitosan with glutaraldehyde, sodium tripolyphosphate and epichlorohydrin, in the powder or beads form and these materials were characterized through elemental analysis, infrared spectroscopy, carbon 13 nuclear magnetic resonance, x-ray diffraction and thermogravimetry. These surfaces were used to metallic cation sorption from aqueous solution, and the thermodynamic parameters for these interactions were determined. Unmodified chitosan presents the following sorption order for metallic cations on its surface: Cu > Cd > Ni > Pb > Co > Zn. This sequence is in agreement with the Irving-Williams series, which demonstrates a stability of formation of those metallic compounds. The copper presented excellent values of sorption, being the largest value found for the QMN material, chitosan modified with maleic anhydride and ethylenediamine, being of 2,36 ± 0,05 mmol g, reflecting the improvement in the sorption capacity through chitosan chemical modification, since the copper sorption capacity for non modified chitosan was found to be 1,39 ± 0,04 mmol g. The chitosan QES, modified with ethylene sulfide, presented good capacity to sorbs lead and cadmium from aqueous solution, being that capacity of 1,80±0,01 and 1,95 ± 0,02 mmol g, respectively. Chitosan beads presented a larger sorption capacity to the unmodified chitosan powder and the beads showed a larger stability and easiness as for the manipulation. All the sorption data were well adjusted to the Langmuir model. The values of free energy show the spontaneity of all systems, which presented negative values for entropy in some cases. The variation of resulting enthalpy for the interaction between copper and the modified chitosan QMN gave the highest value for this metal, -51,64±0,03 kJ mol, as well as the chitosan QES that presented the values -52,37±0,01 and -63,52±0,02 kJ mol for lead and copper interactions, respectively.
Doutorado
Quimica Inorganica
Doutor em Ciências

Orientador: José de Alencar Simoni
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: O presente estudo investiga a influência da adição de alguns xenobióticos comuns em práticas agrícolas, na atividade microbiana de três solos de diferentes regiões, utilizando a calorimetria isotérmica. Amostras de Latosolo vermelho do Brasil: Unik (Unicamp-Campinas) de mata original, Lebra (Leme-SP) cultivada por algodão, e Pak (Faisalabad, Paquistão) cultivada por algodão. Esses solos foram caracterizados por análise elementar de CHN, pH e acidez total, análise microbiológica e análises térmicas (TGA e DSC). A atividade microbiana foi acompanhada por calorimetria isotérmica, com o objetivo de se investigar a influência de fatores como: tempo de armazenamento, estação de coleta, adição de herbicidas do grupo das sulfoniluréias; clorimuron e metsulfurom, e arsênio. Utilizou-se a glicose como substrato principal, como fonte de carbono, nesse estudo. Os principais resultados evidenciam que o uso dos herbicidas conjuntamente com glicose aumentou a liberação de energia e, portanto, de CO2, quando comparado à adição simples de glicose. A emissão de CO2 (catabolismo) também foi maior para os solos com cultivo intensivo de monocultura de algodão, sendo que a ordem de emissão foi Pak>Lebra>Unik1. Por outro lado a adição de As provoca uma diminuição do catabolismo e, portanto, diminuindo a emissão de CO2
Abstract: The present study investigates the influence of the addition of some xenobiotics, commonly used in agricultural practices, on the microbial activity of soils from three different regions, by using isothermal calorimetry. Samples of red Latosol from Brazil: Unik (Unicamp-Campinas) of the original forest, Lebra (Leme, São Paulo) cultivated with cotton, and Pak (Faisalabad, Pakistan) cultivated with cotton. These soils were characterized by CHN elemental analysis, pH, total acidity, microbiological analysis and thermal analysis (TGA and DSC). Microbial activity was monitored by isothermal calorimetry, in order to investigate the influence of factors such as time of storage, collection station, the addition of the sulfonylurea herbicides, chlorimuron and metsulfuron, and arsenic ion. Glucose was used as main substrate as carbon source in this study. The main results show that the use of the herbicides together with glucose increased the release of energy, so CO2, compared to the simple addition of glucose. The CO2 emissions (catabolism) was also higher for soils with intensive cultivation of cotton monoculture, and the order was Pak > Lebra > Unik1. Moreover the addition of As causes a decrease in catabolism and thus decreasing the CO2 production to the environment
Doutorado
Físico-Química
Doutor em Ciências

Orientador: Claudio Airoldi
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: O biopolímero quitosana foi sintetizado através da desacetilação alcalina do polissacarídeo precursor quitina, mediante reação com hidróxido de sódio e o seu grau de desacetilação foi determinado a partir da espectroscopia de absorção na região do infravermelho. A quitosana foi quimicamente modificada através de reações com acetilacetona, epicloridrina e glutaraldeído, explorando-se a reatividade dos grupos hidroxila e amino livres da estrutura polimérica original. Os derivados na forma de pó foram usados como sorventes para o cátion cobre em solução aquosa. Esferas de quitosana reticulada com Cu foram obtidas através de uma única etapa de reação, o que foi possível devido à grande habilidade do biopolímero em se coordenar ao cátion, através da disponibilidade da função amina na estrutura polimérica. Por adaptação dessa nova metodologia foram obtidas também esferas com Ni e Co. Os novos biopolímeros sintetizados contendo cobre e níquel atuaram com sucesso na remoção de monoaminas de soluções aquosas. Os dados termodinâmicos calculados a partir da titulação calorimétrica mostram que, na sorção do cátion cobre com quitosanas quimicamente modificadas ou de aminas com esferas reticuladas, os efeitos interativos são favoráveis e espontâneos, refletindo em entalpias exotérmicas e valores negativos de energias de Gibbs. Os valores positivos das entropias refletem um aumento de espécies livres em solução, após o efeito interativo, decorrentes da liberação de moléculas do solvente, com dessolvatação tanto do biopolímero, como do cátion ou das moléculas de aminas ligadas ao solvente
Abstract: The biopolymer chitosan was synthesized by alkaline deacetylation of the precursor polysaccharide chitin by reaction with sodium hydroxide, which degree of deacetilation was determined from absorption spectroscopy in the infrared region. Chitosan were chemically modified by reactions with acetylacetone, glutaraldehyde and epichlorohydrin, exploring the reactivity of hydroxyl and amino free pendant groups linked to original polymeric structure. The derivatives in powder form were used as sorbents for copper cation in aqueous solution. Beads of chitosan crosslinked with Cu were obtained from one step reaction, due to the fact that the biopolymer has high ability in cation coordination, through the availability of the amine functions in the polymeric structure. Based on this methodology other spheres containing Ni and Co were also synthesized. The new biopolymers crosslinked with copper and nickel act with success in monoamine removal from aqueous solution. Thermodynamic data calculated from calorimetric titration show that the copper cation sorption on chitosan chemically modified or amines with crosslinked beads at the solid/liquid interface, gave exothermic enthalpies and negative Gibbs energy values, demonstrating that the interactive effects are thermodynamically favorable and spontaneous. The entropic positive values reflect an increase in free species in solution, after interactive effect due to the solvent molecules released, with biopolymer desolvation, as well as, from cation in solution or solvent molecules bonded to aliphatic amines
Doutorado
Quimica Inorganica
Doutor em Ciências

In the recent years, the legislation related to the safety of industrial processes has become more rigorous and demanding than in the past. The design of inherently safe processes is currently' viewed as a necessary target of the engineering discipline (Gupta and Ed~ards, 2002).. Alkylpyridines and their N-oxides are being used widely as intermediates and final products in the Phannaceutical Industry. Under typical industrial conditions the N-oxidation reaction is performed catalytically, in the liquid phaSe in a semi-batch mode. Hydrogen peroxide is used as the oxidising agent. It is dosed over the alkylpyridine-catalyst mixture over a period of time. The desired N-oxidation is accompanied by one only additional reaction, the lpldesired decomposition ofhydrogen peroxide. The catalytic N-oxidation of selected picolines, lutidines and collidines were performed in an HEL SIMULAR® lL calorimeter at conditions very close to the industrial'ones, following a certain procedure. The catalytic decomposition of hydrogen peroxide alone, under the same conditions was also studied. A sensitive mass flow-meter MKS 1179A Mass-Flo® was used for the continuous measurement of the oxygen produced by the decomposition of hydrogen peroxide, thus .allowing the split of the power of the two reactions. The heat of reaction has been evaluated for all the selected N-oxidation and hydrogen peroxide decomposition reactions. The concentration of the a1kylpyridines and their N-oxides was measured using HPLC. These measurements confirmed that the hydrogen peroxide decompositio~ was the only parallel reaction. Integration of the thermal power evolution curves also provided a continuous measure of concentration.. These curves were found to be in good agreement with the HPLC measurements. The reactions were studied using heat-flow and power compensation calorimetry at subcooled conditions. Their study shows that their N-oxidation follows Langmuir type kinetics. The paraIlel decomposition ofhydrogen peroxide also follows the same type ofkinetics. Their kinetic study was based on the kinetic model of Sempere et al, 1998, whi~h was improved and refined. The model of Sempere et al., 1998 on a-picoline assumes paths of reaction, in which, the employed· catalyst, phosphotungstic acid, does not participate. However, as reported in our previous work (papadaki et al., 2002a), no reaction takes place in the absence of phosphotungstic acid. The kinetic model proposed by Sempere et al. 1998 has thus been modified to account for those paths. The modified model is, as before, based on the assumption of very fast always in equilibrium reactions or interactions for the formation of intermediates which subsequently react in a number of ways to give the final products. All paths of the modified model are catalytic. The new kinetic model has been tested and found to be,:in good agreement with experimental data. A number of runaway scenarios of the excess of hydrogen peroxide used during the N-oxidation of alkylpyridines, under closed and open conditions, were examined. It was found that, in most cases, if the volume of the liquid hydrogen peroxide solution occupies more than 10% ofthe total volume ofa closed system (e.g. reactor and vent line between reactor and blockage), the production of gases raises the pressure so quickly that evaporation is completely suppressed. Higher that 70% filling levels result in complete expansion of the liquid~The MTSR(t) (the inaximum temperature attained by the synthesis reaction) of the system falls rapidly if th~ normal process temperature is high, but if a runaway.occurs exactly at the end of dosing, MTST (the maximum temperature reached during the synthesis reaction) will be very high and secondary decompositions will rapidly develop. The results of this study are currently being used to critically assess the current approaches and to further the study ofinherently safer designs.

L'amélioration de la résolution en énergie des calorimètres hadroniques est adressée dans cette thèse. L'approche envisagée se base sur la technique du dual-readout qui consiste à détecter simultanément les radiations Cherenkov et la scintillation. La comparaison de ces deux signaux permet en effet de compenser les fluctuations observées dans la détection de gerbes hadroniques. Les grenats d'Aluminium et de Lutetium (LuAG), qui sont d'efficaces scintillateurs une fois activés avec des terres rares, peuvent aussi jouer le rôle de radiateur Cherenkov sous leur forme non-dopée. Les deux types de matériaux peuvent alors être assemblés pour former un calorimètre dual-readout performant. Dans l'objectif d'étudier la faisabilité de ce concept, les effets de la concentration en dopant et de l'addition de divers codopants sur le rendement lumineux et les propriétés temporelles ont été étudiés. Nous avons montré le rôle important de la technique de croissance choisie sur la nature et la concentration des défauts structuraux. La géométrie optimale, qui se base sur des monocristaux en forme de fibres, donne l'avantage à la technique de micro-pulling down. Cette technologie ne montre pas de meilleurs résultats que les techniques de Bridgman et de Czochralski mais a été retenue pour des raisons de coût et d'adaptabilité pour une production à grande échelle. L'optimisation des paramètres de croissance a permis la production de fibres monocristallines de LuAG dopées avec du Cérium présentant un rendement lumineux de 8000 photons par MeV et un bon comportement en tant que guide de lumière grâce à une qualité optique bien maitrisée. Des tests avec des faisceaux d'électrons et de pions, en conditions de calorimétrie à haute énergie, permettent désormais d'envisager la production d'un prototype à plus grande échelle
This thesis focuses on the improvement of the energy resolution of hadron calorimeters. The approach is based on dual-readout, which consists in the simultaneous detection of both scintillation and Cherenkov light. The comparison of these two signals allows a compensation of the energy fluctuations, which are inherent to the detection of hadronic showers. Lutetium Aluminium garnets (LuAG), which are efficient scintillators when activated with rare-earth dopants (i.e. Cerium), can also act as Cherenkov radiators when undoped. Both undoped and doped crystals can then be assembled to build an efficient dual-readout calorimeter. With the objective to investigate the feasibility of this concept, the effects of the doping concentration and the use of various co-dopant on the light output and the timing properties of LuAG were studied. The growth method was demonstrated to induce significant differences in the nature and concentration of structural defects. The optimum geometry, which is based on singlecrystals shaped into fibers, favors the micro-pulling down technique. This technology does not outperform Bridgman and Czochralski techniques but was chosen on bases of cost considerations and large scale productions abilities. The optimization of the growth parameters led to the production of single-crystalline fibers of Cerium-doped LuAG with a light output of 8000 photons per MeV and an adequate behavior as light guide due to a well-controlled optical quality. Test with electrons and pions in high energy calorimetry conditions allow to engage a future production of a larger-scale prototype

Wildland fire is a natural part of the earth’s phenomenological pattern and like most natural phenomena has presented a challenge to human activity and engineering science. Wildfire presents Fire Safety Engineering with the task of developing fundamental research and designing analysis tools to address fire on a scale where interactions with atmospheric and terrestrial conditions dominate fire behavior. The research work presented in this thesis addresses a fundamental research issue involving transport processes in porous wildland fuel beds. This research project had the specific goal of developing an understanding of how transport processes affected the combustion of wildland fuels that were in the form of a porous bed. No detailed study could be found in the literature that specifically addressed how the fuel structure affected the combustion process in these types of fuels. To this end, a series of experiments were designed and carried out that approached the understanding of this problem using commonly available fire testing equipment, specifically the cone calorimeter and the FM Global Fire Propagation Apparatus. The goal of this research study and the basis for the novel and relevant contribution to the field of engineering was to conduct an experimental test series, analyze the data and examine the scalability of the results, to determine the effect of transport processes on the Heat Release Rate (HRR) of porous wildland fuels. The project concluded that flow dominates HRR in fires involving the wildland fuels tested. A dimensionless analysis of the fuel sample baskets showed consistency with well established mass transfer, fluid flow and chemical kinetic relationships. The dimensionless analysis also indicates that the experimental results should be scalable to similar configurations in larger fuel beds. One conclusion of this study was that wildland fire modeling efforts should invest in understanding flow conditions in fuel beds because this behavior dominates over the chemical kinetics of combustion for predicting HRR which is an important parameter in fire modeling.

La mesure précise de la masse du boson W est une composante essentielle pour tester la cohérence globale du Modèle Standard, dont une défaillance pourrait mettre à jour la nouvelle physique. Avec des millions de bosons W prévus, les futures expériences seront des usines à bosons permettant de mesurer sa masse avec une précision inégalée. La mesure de la masse du W est discutée dans le contexte de deux expériences : l'amélioration du détecteur CMS au LHC, le HL-LHC, avec un nouveau bouchon calorimétrique, le HGCal, et à un détecteur pour FCC-ee, un projet circulaire post-LHC. En collision proton-proton, la mesure précise de la masse du boson W dépend de la précision de la mesure du recul hadronique. Cette précision dépend principalement de la définition du recul et des effets induits par le détecteur. La définition du recul est améliorée par des méthodes de machine learning, en utilisant une régression quantile multivariée. Les effets de la granularité, de l'acceptance et de la résolution du HGCal sur le recul sont évalués. Cette étude donne une estimation de la précision sur la masse du boson W qui pourrait être atteinte au HL-LHC. Avant d'estimer les effets de la performance du détecteur sur le recul, la géométrie complète et les paramètres du détecteur ont été ajustés et optimisés. Un fidèle outil de simulation rapide, complément au logiciel de simulation complet de CMS, implémenté pour mener cette étude, est présenté. En collision électron-positron, la masse du boson W peut être déterminée à partir du produit de désintégration de la paire de W. Les incertitudes statistiques sur la masse et la largeur sont estimées en utilisant la méthode du fit cinématique, dans les canaux de désintégration hadronique et semi-leptonique à 162,6 GeV, 240 GeV et 365 GeV. Atteignant une incertitude statistique inférieure au niveau du MeV/c² à toutes les énergies et pour les deux canaux, la mesure de la masse du W devient limitée par les incertitudes systématiques. Un traitement pour réduire l'incertitude systématique engendrée par les effets QCD, la plus large source d'incertitude systématique à LEP, et son impact sur l'incertitude statistique sont également étudiées
The precise measure of the W boson mass is an essential input to a crucial test of the overall consistency of the Standard Model, whose failure might reveal the emergence of new physics. With millions of W bosons expected, future experiments will be W boson factories allowing the measurement of the W mass with unparalleled precision. The W mass measurement is discussed in the context of two experiments: the upgrade of CMS at the LHC, the HL-LHC, with a new endcap calorimeter, the HGCal, and a detector for the FCC-ee, a circular post-LHC project. In proton-proton collisions, the precise measurement of the W mass relies on a precise measurement of the hadronic recoil. Its accurate measurement mainly depends on its definition model and detector effects. The recoil definition is improved with machine learning techniques, using a multivariate quantile regression. The effects of the HGCal granularity, acceptance and resolution on the recoil reconstruction are evaluated. This study gives an estimate of the precision that might be reached on the W mass measurement at HL-LHC. Before evaluating the effect of the detector performance on the recoil, the full geometry and parameters had to be tuned and optimised. An accurate fast simulation tool, complement to the full CMS simulation, implemented to undertake such a study, is presented. In electron-positron collisions, the W mass can be determined from the W-pair decay products. The statistical uncertainties on the W mass and width are estimated using a kinematic fit technique in the hadronic and semi-leptonic channels at 162.6 GeV, 240 GeV and 365 GeV. Reaching a statistical precision below the MeV/c² level at all energies for both channels, the W mass measurement becomes limited by the systematic uncertainties. A treatment to reduce the systematic uncertainty coming from QCD effects, the largest source of systematic uncertainty at LEP, and its impact on the statistical uncertainty are also studied

The research described in this thesis focused on the TMDSC technique with respect to both theoretical problems and applications. Theoretically, modelling work has been performed to address the effects of heat transfer in the measuring cell on both dynamic and quasi-isothermal TMDSC experiments. The problems of heat transfer generally influence the measured complex heat capacity and phase angle values, but eventually affect the precise measurements of other frequency dependent quantities such as the in-phase and out-of-phase heat capacities. A procedure has been suggested to correct the measured phase angle obtained by dynamic TMDSC using the scaled complex heat capacity trace (Chapter 3). The modulation frequency dependence of the instrumental phase angle has been fully investigated using more realistic models in terms of various heat transfer interface qualities, sample properties and sensor properties. In these models, it is emphasised that the measured temperatures are the sensor temperatures rather than the sample temperatures, thus, the contributions of the sensor's properties to the heat transfer are, for the first time, separated from the overall effects (Chapter 4 and Chapter 5). The consequent effects of heat transfer on the sample's heat capacity measurements are investigated based on the models suggested (Chapter 6). All the modelling results are compared with the corresponding experimental data obtained by ADSC (Mettler-Toledo Ltd) and they are in good agreement. Ripples and fluctuations which appear on the experimental signals during the glass transition and cold crystallisation transition have been simulated using* a simple model in which the period of the modulation signals changes with the time during the transitions, and then, been shown to be artefacts of the Fourier transformation process used by TMDSC evaluations (Chapter 7). The applications of TMDSC to both research and commercial samples are reported in terms of differing either the experimental conditions or the thermal history of the sample. Separating of time dependent kinetic processes from the time independent dynamic processes has been applied on the studies of the glass transition (for polycarbonate and poly(ethylene terephthalate)), the cold crystallisation (for poly(ethylene terephthalate)), the melting transition (for poly(ethylene terephthalate) and lead/tin alloys), the clearing transition of a liquid crystal polymer, and the vitrification of an epoxy resin under quasi-isothermal conditions. The main conclusion drawn from these studies is that the in-phase heat capacity is greatly influenced by the frequency of the temperature modulations even when the underlying heating (or cooling) rate remains the same. This strongly implies that the sample undergoes different structural change under different modulation conditions for the melting transition and clearing transition, but not for the glass transition and cold crystallisation. However, the interpretations of the in-phase heat capacity and out-of- phase heat capacity still need to be clarified. The detection of the glass transition and clearing point for the liquid crystal polymers, and the determination of wax appearance temperature for crude oils, show the ability of TMDSC for combining the sensitivity of a measurement at high instantaneous heating or cooling rates with the resolution obtained by measuring at a low underlying heating or cooling rates. The work on the isothermal curing of the epoxy resins displays the ability of TMDSC on measuring the heat capacity of the sample and its variation under the quasi-isothermal conditions. The frequency dependent complex heat capacity during the glass transition provides a window to measure the apparent activation energy of the transition, which is different, in some extent, from the window used by conventional DSC. The results are correlated by a shift factor. Some shortcomings of TMDSC, however, have been noticed in both modelling and application work. Firstly, any experiments for the purpose of either understanding or the quantitative measurements of TMDSC output quantities should be performed under carefully selected conditions which can satisfy the linear response assumption. Secondly, some signals in particular those associated with kinetic processes may not be fully sampled by TMDSC due to the limit of the observing window of a modulation. Thirdly, when the sensitivity is improved on TMDSC by separating the kinetics processes and noises from the dynamic processes, the TMDSC evaluation procedure introduces mathematical artefacts into the output signals. As a consequence, it is preferable to include as many temperature modulations as possible within any transition being studied in order to obtain good quality experimental signals by eliminating or minimising these artefacts, which, however, is not an easy task for some very abrupt transitions such as melting of metals.

Orientador: Watson Loh
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: O tema desta tese como sugerido pelo titulo aborda assuntos correlacionados com formação de sistemas binários de copolímeros em diferentes solventes como também com a interação entre copolímeros bloco e estatísticos de oxido de poli etileno e oxido de poli propileno com vários tipos de surfatantes iônicos: catiônicos, aniônicos e não iônicos. Os estudos deste trabalho foram divididos em três etapas, que foram concluídas com duas publicações e um manuscrito. Em primeiro artigo incluiu se todas as investigações correspondentes aos estudos de interação entre copolímeros em bloco P123 e surfatante não iônico C12EO6 monitorada por calorimetria e espalhamento de luz. Através deste estudo o novo fenômeno para sistema de P123 - C12EO6 foi observado, chamado de transição esferas-bastonetes e identificou-se alta aplicação de técnicas calorimétricas para monitoramento deste tipo de eventos intermoleculares. Este estudo foi executado em colaboração com o grupo de pesquisa da Universidade Lund na Suécia, que conduziu todos os experimentos que envolvem o espalhamento de luz. Por outro lado os experimentos na parte de calorimetria foram feitos dentro do nosso grupo. O segundo artigo descreve sistemas de copolímeros em bloco vs. estatísticos na interação com surfatantes iônicos: aniônicos, catiônicos. Estes estudos revelaram que copolímeros estatísticos interagem com copolímeros aniônicos da maneira parecida com que homopolímeros hidrofílicos. Efeito de temperatura foi investigado também através das técnicas calorimétricas e tendências previamente relatadas foram confirmadas. Como parte complementar a este artigo foram incluídos nesta tese alguns resultados calorimétricos da interação entre copolímeros estatísticos na região do ponto de turvação deles e surfatantes não iônicos, confirmando mais uma vez o que é conhecido da literatura que os surfatantes não-iônicos geralmente não interagem associativamente com polímeros não-iônicos e esta interação é especial para sistema P123 - C12EO6. Por último inclui se neste trabalho o manuscrito que contem um estudo comparativo de sistemas bifásicos de copolímeros em bloco vs. estatísticos. Verificou se neste estudo que os copolímeros estatísticos apresentam diferente comportamento na separação de fases, do que copolímeros em bloco. Devido a falta de auto - agregação destes copolímeros os pontos de turvação deles são menos elevados em comparação com copolímeros em bloco o que devido a esta propriedade tem enorme aplicação na área acadêmica em bioquímica e biotecnologia para purificação de materiais biológicos como também em outras áreas: analise de poluentes, compostos orgânicos,metais
Abstract: The subject of the thesis, as suggested by the title, draws on the formation of binary systems of copolymers in different solvents, as well as interaction of block and random copolymers of poly (ethylene oxide) and poly (propylene oxide) with various types of ionic surfactants: cationic, anionic and non-ionic. These studies are divided in three stages and each of it was concluded with publication or manuscript. In the first article it is included all investigation on interaction between block copolymer P123 and noni-onic surfactant C12EO6 monitored by calorimetry and light scattering. By applying these techniques a new phenomenon was observed in the P123-C12EO6 system, namely a well-defined sphere-to-rod transition of the mixed micelles and interesting application of calorimetric techniques has been identified due to its high sensitivity to this kind of intermolecular events detection. These studies were performed in collaboration with our partners from Lund University, Sweden, who conducted light scattering measurements. On the other hand, measurements on calorimetry have been done within our research group. Moreover, in the second paper interactions between random vs. block copolymers with ionic surfactants (cationic and anionic) has been discussed. These studies revealed an interaction similar to that observed with other hydrophilic homopolymers. Effects of temperature and of the nature of the ionic surfactants on their interaction with these copolymers were found to agree with the previously reported trends. As a complementary part of this article some additional results on interaction between random copolymer and non-ionic surfactants have been included in this thesis. Once again it was confirmed what is reported in the literature that non-ionic surfactants generally do not interact associatively with non-ionic polymers and interaction between P123 and C12EO6 is special to this system. As the last, it was included in this work the manuscript, which contains the comparative studies of biphasic systems constructed from block vs. random copolymers. It was verified in this studies that random copolymers present different phase behaviour than block copolymers. Lack of auto-association of these copolymers promotes their cloud points to be lower then cloud points of block copolymers. Due to this property these copolymers has enormous application in academic area in biochemistry or biotechnology for purification of biological materials as well as in other areas: for pollutants analysis, organic materials or metals
Doutorado
Físico-Química
Doutor em Ciências

El teixit adipós marró (TAM) està format principalment per adipòcits marrons, la funció principal dels quals és el manteniment de la temperatura corporal de l’organisme a través de la termogènesi adaptativa. La capacitat termogènica de TAM ve donada per l’expressió de la proteïna desacobladora 1 (UCP1), una proteïna mitocondrial capaç de desacoblar la cadena respiratòria de la fosforilació oxidativa, generant calor enlloc d’ATP. Els treballs realitzats en la present tesi doctoral han estat orientats en l’estudi de la implicació de l’autofàgia en els processos adaptatius relacionats amb la funció termogènica que tenen lloc en el TAM. En el moment d’iniciar aquesta tesis existien pocs estudis sobre el paper de l’autofàgia en la biologia del TAM, ja que els estudis publicats en aquell moment principalment havien centrat l’atenció en el paper de l’autofàgia en el teixit adipós blanc. Vam hipotetitzar que l’autofàgia podria ser un procés important per a la funció termogènica en el TAM. Entre els processos autofàgics, la degradació de mitocondris (mitofàgia) és un mecanisme de control de qualitat destinat al manteniment d’una xarxa mitocondrial en bones condicions. La mitofàgia és d’especial rellevància en cèl·lules amb alta capacitat oxidativa, com les cèl·lules musculars o les neurones. En canvi, a l’inici d’aquesta tesi el paper de la mitofàgia en el TAM, un dels teixits amb més capacitat oxidativa, no havia estat descrit. En aquest projecte es va identificar Parkin, una de les principals proteïnes relacionades amb la mitofàgia, com a un nou factor implicat en el control de la capacitat termogènica del TAM. L’anàlisi de la regulació de l’autofàgia durant l’activació termogènica utilitzant models in vivo (exposició al fred ) i in vitro (cultius primaris d’adipòcits marrons) ens va permetre determinar que l’autofàgia és reprimida en associació amb l’activació de la termogènesi en el TAM. A més a més, en condicions basals, els adipòcits marrons mostren signes d’activitat lipofàgica, la qual es veu suprimida per l’estímul termogènic. Aquest efecte és reproduïble en adipòcits marrons per l’acció de la noradrenalina, la qual actua mitjançant l’cAMP, principalment a través de la via de la proteïna cinasa A. La inhibició de l’autofàgia en adipòcits marrons promou un increment en els nivells d’expressió de la proteïna UCP1, i un increment en la respiració desacoblada. Un dels principals mecanismes per induir la mitofàgia és el reclutament de la proteïna Parkin als mitocondris danyats. La translocació de Parkin als mitocondris és mitjançada per la cinasa putativa induïda per PTEN 1 (PINK1), que actua com a sensor de dany mitocondrial. En aquest estudi descrivim que l’expressió de Parkin es veu fortament reprimida en el TAM de ratolins durant l’activació termogènica, mentre que PINK1 s’estabilitza als mitocondris. D’aquesta manera, la repressió de Parkin podria actuar de mecanisme regulador per tal de prevenir la degradació de mitocondris degut a la despolarització que es troba intrínsecament associada a l’activació termogènica. D’acord a la reciprocitat existent entre els nivells baixos de Parkin i l’activitat del TAM, els ratolins genèticament modificats per la falta d’expressió de Parkin presenten una elevada activitat termogènica en el TAM i són resistent a l’obesitat. Utilitzant adipòcits marrons en cultiu, vam trobar que la repressió de Parkin depèn principalment de mecanismes dependents de senyalització per àcids grassos. A més a més, el sistema PINK1-Parkin es troba activat durant la desaclimatació al fred, una situació en la qual el TAM s’inactiva i que alhora implica la pèrdua massiva de proteïna mitocondrial al teixit. En resum, els resultats d’aquesta tesi ens han permès determinar que l’autofàgia i, especialment, la mitofàgia, actuen com a reguladors negatius de l’activitat termogènica del TAM.
Brown adipose tissue (BAT) is the main site of non-shivering thermogenesis, a mechanism of heat production that enables the organism to adapt to a cold environment. Brown adipocytes possess large amounts of mitochondria with a high oxidative capacity due to the expression of uncoupling protein 1 (UCP1). UPC1 uncouples the respiratory chain from oxidative phosphorylation yielding a high oxidation rate. Moreover, energy expenditure derived from BAT thermogenic activity provides a protective mechanism against obesity. Autophagy is a process that contributes to the maintenance of cellular homeostasis by degrading damaged or no longer needed organelles and cytoplasmic substrates into lysosomes. At the beginning of this thesis the role of autophagy in the adaptation of BAT to thermogenic activation had not been determined. We analyzed the effects of thermogenic activation in autophagy using in vivo and in vitro models. We found that autophagy is repressed in association with cold-induced thermogenic activation of BAT in mice. This effect was mimicked by NE action in brown adipocytes, acting mainly through a cAMP-dependent protein kinase A pathway. Moreover, we described the presence of active lipophagy in brown adipocytes under basal conditions, which is suppressed by the thermogenic stimulus. Reciprocally, inhibition of autophagy in brown adipocytes leads to an increase in UCP1 protein and uncoupled respiration. We also reported that Parkin, a protein implicated in the selective degradation of mitochondria (mitophagy), was repressed during BAT thermogenic activation, a transcriptional mechanism controlled by free fatty acids related pathways. Parkin is activated by PINK1, a protein that is stabilized in the outer membrane of damaged mitochondrial. We report that PINK1 is stabilized during thermogenic activation, probably in response to UCP1-mediated mitochondrial depolarization. Our data support the possibility that Parkin downregulation may be a compensatory mechanism to prevent PINK1-induced mitophagy. Otherwise, the PINK1-Parkin system is induced during cold-deacclimation, a situation of BAT inactivation. In accordance with the reciprocal association between low Parkin levels and BAT activity, mice lacking Parkin had an enhanced thermogenic activity and were resistant to diet-induced insulin resistance and obesity. In conclusion, autophagy and especially mitophagy are processes associated negatively with BAT thermogenic activation.
El tejido adiposo marrón (TAM) está formado principalmente por adipocitos marrones, la función principal de los cuales es el mantenimiento de la temperatura corporal del organismo a través de la termogénesis adaptativa. La capacidad termogénica de TAM viene dada por la expresión de la proteína desacopladora 1 (UCP1), una proteína mitocondrial capaz de desacoplar la cadena respiratoria de la fosforilación oxidativa, generando calor en vez de ATP. Los trabajos realizados en la presente tesis doctoral han sido orientados en el estudio de la implicación de la autofagia en los procesos adaptativos relacionados con la función termogénica en el TAM. En el momento de iniciar esta tesis existían pocos estudios sobre el papel de la autofagia en la biología del TAM, ya que los estudios publicados en ese momento principalmente habían centrado la atención en el papel de la autofagia en el tejido adiposo blanco. Nuestra hipótesis fue que la autofagia podría ser un proceso importante para la función termogénica en el TAM. Entre los procesos autofágica, la degradación de mitocondrias (mitofagia) es un mecanismo de control de calidad destinado al mantenimiento de una red mitocondrial en buenas condiciones. La mitofágia es de especial relevancia en células con alta capacidad oxidativa, como las células musculares o las neuronas. En cambio, al inicio de esta tesis el papel de la mitofágia en el TAM, uno de los tejidos con mayor capacidad oxidativa, no había sido descrito. En este proyecto se identificó Parkin, una de las principales proteínas relacionadas con la mitofàgia, como un nuevo factor implicado en el control de la capacidad termogénica del TAM. El análisis de la regulación de la autofagia durante la activación termogénica utilizando modelos in vivo (exposición al frío) e in vitro (cultivos primarios de adipocitos marrones) nos permitió determinar que la autofagia es reprimida en asociación con la activación de la termogénesis. Además, en condiciones basales, los adipocitos marrones muestran signos de actividad lipofágica, viéndose esta suprimida por el estímulo termogénico. Este efecto es reproducible en adipocitos marrones por la acción de la noradrenalina, la cual actúa mediante la cAMP, principalmente a través de la vía de la proteína quinasa A. La inhibición de la autofagia en adipocitos marrones promueve un incremento en los niveles de expresión de la proteína UCP1, y un incremento en la respiración desacoplada. Uno de los principales mecanismos para inducir la mitofágia es el reclutamiento de la proteína Parkin en las mitocondrias dañados. La translocación de Parkin en las mitocondrias es mediada por la quinasa putativa inducida por PTEN 1 (PINK1), que actúa como sensor de daño mitocondrial. En este estudio describimos que la expresión de Parkin se ve fuertemente reprimida en el TAM de ratones durante la activación termogénica, mientras que PINK1 se ve estabilizada en las mitocondrias. De este modo, la represión de Parkin podría actuar de mecanismo regulador para prevenir la degradación de mitocondrias debido a la despolarización que se encuentra intrínsecamente asociada a la activación termogénica. De acuerdo a la reciprocidad existente entre los niveles bajos de Parkin y la actividad del TAM, los ratones genéticamente modificados por la falta de expresión de Parkin (Parkin-KO) presentan una elevada actividad termogénica en el TAM y son resistentes a la obesidad. Utilizando adipocitos marrones en cultivo, describimos que la represión de Parkin depende principalmente de mecanismos dependientes de señalización por ácidos grasos. Por otro lado, el sistema PINK1-Parkin se encuentra activado durante la desaclimatación al frío, una situación de inactivación del TAM que implica la pérdida masiva de proteína mitocondrial. En resumen, los resultados de esta tesis nos han permitido determinar que la autofagia y, especialmente, la mitofàgia, actúan como reguladores negativos de la actividad termogénica del TAM.

ce rapport résume les développements réalisés en électronique pour lire le calorimètre à Argon Liquide (LAr) d'ATLAS au LHC puis le R&D effectué dans CALICE pour lire ceux de l'ILC en passant par les circuits développés pour lire les photomultiplicateurs multi-anode (MaPMT) pour OPERA ou pour la luminosité d'ATLAS et qui ont aussi des applications en imagerie médicale. Commencée au début des années 90, le R&D pour la calorimétrie d'ATLAS était extrêmement challenging en termes de vitesse de lecture, tenue aux radiations et précision de mesure. La vitesse élevée a nécessité une nouvelle approche de préamplificateurs de courant plutôt que de charge et la définition du bruit en ENI. Les préamplificateurs ont été développés a Orsay ainsi que les shapers monolithiques, ils sont détaillés dans le chapitre 1 ainsi que les considérations sur le filtrage numérique, qui constituait une nouveauté pour la communauté et qui ne donnait pas les résultas escomptés au début. Le chapitre 2 est consacré au système de calibration, développé et produit par Orsay et dont la performance poussée a nécessité des études approfondies. Le chapitre 3 clôt les études pour ATLAS avec un résumé des mesures qui ont dû être faites sur les 200 000 voies du détecteur pour le comprendre et le modéliser afin d'atteindre partout la précision et l'uniformité meilleures que le pourcent. Ces travaux pour ATLAS se sont achevés en 2004, même si des développements ont été réalisés pour les calorimètres de NA48 et D0 durant cette même période et sur des sujets connexes qui ne sont pas détaillés ici. La prochaine génération de collisionneurs après le LHC nécessitera une nouvelle génération de calorimètres, beaucoup plus granulaires (on parle d' « imaging calorimetry », avec des centaines de millions de canaux) et d'électronique de lecture intégrée dans le détecteur. Les ASICs développés pour cette application dans le cadre de la collaboration « CALICE » sont décrits au chapitre 4. Ils intègrent toutes les fonctions d'amplification, digitisation et lecture intégrée qui ont font de véritables « Systems On Chip » (SoC). Une famille de 3 circuits permet de lire le calorimètre électromagnétique Silicium-Tungstène, les RPCs du calorimètre hadronique digital ou les SiPM du calorimètre hadronique analogique ; très performants et versatiles, ils trouvent de nombreuses applications extérieures Ces circuits ont repris de précédents blocs de chips mis au point dans les années 2000 pour lire les photomultiplicateurs multi-anodes du Target Tracker de l'expérience OPERA puis du luminomètre de l'expérience ATLAS et qui sont décrits au chapitre 5 Ces circuits trouvent une continuation actuelle dans les photodétecteurs intégrés de grandes dimensions, développés pour de futures expériences Neutrino.

The interactions of CO, NO and O₂ with Pt{111}, pt{211}, and Pt{411} have been investigated with Single Crystal Adsorption Calorimetry (SCAC). Coverage-dependent heat of adsorption and sticking probability data for 300 K are presented, and are discussed with respect to the kinetics and thermodynamics of adsorption and desorption. CO adsorption proceeds molecularly on both Pt{111} and Pt{411}, with initial sticking probabilities of 0.78 and 0.80, and initial heats of adsorption of 176 kJ mol^-1 and 196 kJ mol^-1, respectively. Both adsorbate layers are found to be non-localised, having identical pre-exponential factors of 2x10¹⁵ s^-1. Discrepancies between isosteric and calorimetric heat of adsorption data at low coverage for CO/Pt{111} have been rationalised in terms of an entropy-driven localised/non-localised phase transition occurring above 300 K. Initial adsorption of NO occurs with a sticking probability of 0.84 on all three surfaces. The initial heat of adsorption for NO/Pt{411} indicates dissociative adsorption. The NO/Pt adsorbate layers are found to be highly localised, with pre-exponential factors in the range 10¹⁷ – 10²⁰ s^-1. This has been discussed in terms of desorption from highly compressed adsorbate layers in which co-operative effects are extant. O₂ adsorption proceeds dissociatively on all three surfaces, with the initial heats of adsorption all above 300 kJ mol^-1. Desorption occurs from localised adsorbate layers, with all systems having pre-exponential factors of 10¹⁸ s^-1. A kinetic compensation effect has been observed for the data of this thesis, as well as that of the SCAC literature, and is discussed within the context of the chemisorption entropy-enthalpy compensation.

This dissertation is a compilation of research results of extensive Fast Scanning Calorimetry studies of two non-crystalline materials: Toluene and Water.

Motivation for fundamental studies of non-crystalline phases, a brief overview of glassy materials and concepts and definitions related to them is provided in Chapter 1. Chapter 2 provides fundamentals and details of experimental apparata, experimental protocol and calibration procedure.

Chapter 3 & 4 provides extensive studies of stable non-crystalline toluene films of micrometer and nanometer thicknesses grown by vapor deposition at distinct deposition rates and temperatures and probed by Fast Scanning Calorimetry. Fast scanning calorimetry is shown to be extremely sensitive to the structure of the vapor-deposited phase and was used to characterize simultaneously its kinetic stability and its thermodynamic properties. According to our analysis, transformation of vapor -deposited samples of toluene during heating with rates in excess 100,000 K/s follows the zero-order kinetics. The transformation rate correlates strongly with the initial enthalpy of the sample, which increases with the deposition rate according to sub-linear law. Analysis of the transformation kinetics of vapor deposited toluene films of various thicknesses reveal a sudden increase in the transformation rate for films thinner than 250 nm. The change in kinetics correlates with the surface roughness scale of the substrate, which is interpreted as evidence for kinetic anisotropy of the samples. We also show that out-of-equilibrium relaxation kinetics and possibly the enthalpy of vapor-deposited (VD) films of toluene are distinct from those of ordinary supercooled (OS) phase even when the deposition takes place at temperatures above the glass softening (Tg). The implications of these findings for the formation mechanism and structure of vapor deposited stable glasses are discussed.

Chapter 5 and 6 provide detailed Fast Scanning Calorimetry studies of amorphous solid water in bulk and confining geometry (ultrathin films and nano-aggregates). Bulk-like water samples were prepared by vapor-deposition on the surface of a tungsten filament near 140 K where vapor-deposition results in low enthalpy glassy water films. The vapor deposition approach was also used to grow nano-aggregates (2- 20 nm thick) and multiple ultrathin (approximately 50 nm thick) water films alternated with benzene and methanoic films of similar dimensions. When heated from cryogenic temperatures, the ultrathin water films underwent a well manifested glass softening transition at temperatures 20 degrees below the onset of crystallization. The thermograms of nano-aggregates of ASW films show two endotherms at 40 and 10 K below the onset temperatures of crystallization. However, no such transition was observed in bulk-like water samples prior to their crystallization. These results indicate that water in confined geometry demonstrates glass softening dynamics which are dramatically distinct from those of the bulk phase. We attribute these differences to water's interfacial glass transition which occurs at temperatures tens of degrees lower than that in the bulk. Implications of these finding for past studies of glass softening dynamics in various glassy water samples are discussed in chapter 5 and 6.

The application of microwave radiation for processing of glassy and semicrystalline thermoplastics, elastomeric polymers and composites was investigated. The goal of this research was to reveal the relationship between polymer structure and microwave absorptivity, and hence processability. The specimens were subjected to an electric field at 2.45 GHz either inside a rectangular waveguide or in a cylindrical resonant cavity applicator with less than 100 watts applied power. Both travelling wave modes and standing wave modes were examined. Temperatures, powers and times were recorded, leading to the concept of "microwave calorimetry." Low frequency dynamic mechanical and dielectric frequency-temperature spectra were obtained on the materials and combined to conveniently extrapolate structure-property relationships into the GHz region. A correlation was found between the dielectric properties of various polymers and the dipole moments of small molecule analogues. Evaluating heatability was most accurately found to be determined by the magnitude of (ε_S - ε_∞), the oscillator strength. The value of (ε_S - ε_∞) should be used together with the distribution of relaxation times and the activation energies of dipolar dispersion to predict heatability for microwave processing. The critical temperatures, T_C, of dielectric loss were obtained from the intercepts of positive slope tangents of heating rate versus temperature plots at 2.45 GHz for polymers. Microwave processing was rapid above the critical temperature where the maximum dielectric loss fell in the 2.45 GHz frequency domain for efficient coupling of energy to the polymers. Shifting the dielectric relaxation spectrum into the microwave region by directly or indirectly increasing the temperature of each sample was unique and of key importance to processability. A schematic model was proposed to explain the behavior of two-phase materials subjected to microwave heating. Combining the heatability, (ε_S - ε_∞), and the dielectric relaxation spectral response was found to be helpful in evaluating formulations of two-phase materials for electromagnetic radiation processing at high frequencies.
Ph. D.

The common scope of this thesis is the application of structural biology and biophysics to obtain novel data on nuclear proteins that modulate DNA transcription. The proper regulation and functioning of these elements are essential to ensure organism development, homeostasis and survival. Provided that the biological mechanisms under study in this work are not directly related, the thesis is presented as two independent projects. Binding Determinants on the Smad Surface and in Smad Partners Smad transcription factors, as the core intracellular components of TGF- β signalling, are involved in a myriad of cellular activities and gene transcription programs and is usually affected in proliferative and autoimmune diseases. For its correct activity, a series of proteins involved in transcription regulation partner with the active Smad complex in the nucleus, conferring response specificity. Smad-interacting proteins bind to either the MH2 domain or the linker region between domains, with the former being the most commonly-reported binding site. Nevertheless, there is a surprising lack of related structural and biophysical data. As a consequence, any new details revealed on how the interactions of Smad2 (and in extension, any other Smad) with its nuclear partners occur at the atomic label and the physico-chemical details governing these interactions can likely have an impact on the basic and applied research. Smad-interacting proteins FoxH1, NCOA6 and TRIM33 have been studied in this thesis. The sequence regions in transcription factor FoxH1 and co-activator NCOA6 that effectively interact with the Smad2 MH2 domain have been determined, and likely interacting sequences in TRIM33 have been pointed to. Moreover, a tendency for an α-helix secondary structure has been identified by NMR. The elements required for complex crystallisation have been obtained with the aim to obtain structural data regarding interaction surfaces on the Smad2 MH2 domain. If specificity-defining sites can be determined, it opens a door for drug design targeting Smad2 specifically, even the blocking of specific interactions. Such specificity is certainly of interest in oncologic treatments. Mutation of Residues in the Third β-strand of the FBP28 WW2 Domain Results in Alternative Folding Trajectories The main secondary structure typology of amyloid plaques is anti-parallel β-sheet. This structure is acquired following an alternative folding trajectory. The second WW domain of Formin binding protein 28 (FBP28) has been long used as a β-sheet folding model. Moreover, its folding kinetics and its propensity to form amyloid-like fibrils are the reason for an ongoing controversy regarding its folding mechanism The working hypothesis to explain the folding mechanism behind the appearance of the intermediate species is that the formation of contacts defining the β-hairpin2 occurs at a slower rate than those defining β-hairpin1. To address it, seven FBP28 WW2 single-change mutant domains were designed and NMR was used to obtain their structures. Three mutant domains presented remarkable structural characteristics: L455D, L455W and E456Y. In L455D, the orientation of the D455 side chain suggests the existence of a novel water-mediated bond with Y450. L455W presents the peculiarity of a solvent-exposed W455 side-chain yet not heavily affecting the overall domain stability. E456Y, where the inclusion of the bulky Y456 successfully manages to force a rearrangement of surrounding side chains by π-π stacking with W436. Additionally, temperature-induced protein denaturing experiments have been performed and the melting temperatures (Tm) values for each FBP28 WW2 mutant domain, obtained. Experimental data was applied to perform molecular dynamics simulations. These identify additional folding scenarios for L455D and L455W not requiring an intermediate. This indicates that it is in fact slow β- turn2 formation, most likely due to hydrophobic contacts between Y450 and L455, that favour the formation of the folding intermediate implicated in fibril formation.

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Proteins are biopolymers of high nutritional and functional significance has been widely used as food ingredients. The interaction between two different proteins oppositely charged, and can give rise to complex coacervate currently used as an ingredient in food technology or as a microencapsulating agent. The formation of complex coacervates between Lysozyme and Ovalbumin and between Bovine serum albumin (BSA) and Lysozyme has been investigated as a function of pH, mass ratio of total and concentration of NaCl. For both interactions studied, complexing latched in a wide pH range which corresponds to the interval between the pI of proteins. Among Ovalbumin and Lysozyme interaction was more intense in the ratio r = 1 at pH 7.5 and BSA and Lysozyme most complex formation has occurred on the ratio r = 0.5 and pH 9.0. Changes in the ionic strength by adding NaCl negatively affected the interaction between Lysozyme and BSA already at a concentration of 0.01 mol / L and 0.03 mol / L abolished the interaction between Lysozyme and Ovalbumin. Through Potential - zeta can be seen that the formation of insoluble complexes was highest near the pI for all studied reasons, indicating that the interaction is given by neutralization of opposite charges. The Infrared spectra suggested that electrostatic interactions led interactions however, hydrogen bonds also had a hand in the coacervation process for the proteins under study. The micrographs showed that the insoluble complexes showed spherical structure and particle size showed the formation of structures with an average size around 2 ?m, much larger than the observable size for the isolated proteins. The isothermal titration calorimetry showed that the interaction between Lysozyme and Ovalbumin was exothermic and was performed in two steps, the first and second entropy directed enthalpy driven. The differential scanning calorimetry suggested the presence of a single point of denaturation, that the interaction between Lysozyme and BSA led to a new biopolymer with denaturation temperature 67 ? C differs from isolated proteins. These studies suggested that complex coacervates formed between Ovalbumin / Lysozyme and BSA / Lysozyme could be used as the encapsulating bioactive agent or as food ingredients in order to add nutritional value.
Prote?nas s?o biopol?meros de grande import?ncia nutricional e funcional tendo sido amplamente utilizadas como ingredientes alimentares. A intera??o entre duas prote?nas diferentes e opostamente carregadas pode dar origem aos complexo coacervado, atualmente utilizados como ingrediente na tecnologia de alimentos ou como agente de microencapsula??o. A forma??o de complexos coacervados entre Ovalbumina e Lisozima e entre Albumina s?rica bovina (BSA) e Lisozima foi investigada em fun??o do pH, raz?o de massa total e concentra??o de NaCl. Para as duas intera??es estudadas, a complexa??o acorreu em uma ampla faixa de pH, que corresponde ao intervalo entre os pI das prote?nas. Entre Ovalbumina e Lisozima a intera??o foi mais intensa na raz?o r=1 em pH 7,5 e para BSA e Lisozima a maior forma??o de complexos ocorreu na raz?o r=0,5 e pH 9,0. Altera??es na for?a i?nica por adi??o de NaCl influenciaram negativamente a intera??o entre Albumina BSA e Lisozima j? na concentra??o de 0,01 mol/L e a 0,03 mol/L suprimiu a intera??o entre Ovalbumina e Lisozima. Por meio do Potencial - zeta pode-se verificar que a forma??o de complexos insol?veis foi m?xima pr?ximo ao pI para todas as raz?es estudadas, indicando que a intera??o se deu por neutraliza??o de cargas opostas. Os espectros no infravermelho sugeriram que intera??es eletrost?ticas conduziram as intera??es no entanto, liga??es de hidrog?nio tamb?m tiveram participa??o no processo de coacerva??o para as prote?nas em estudo. As micrografias revelaram que os complexos insol?veis apresentavam estrutura esf?rica e o tamanho de part?cula demonstrou a forma??o de estruturas com tamanho m?dio em torno de 2 ?m, as quais s?o bem maiores do que o tamanho obervado para as prote?nas isoladas. A calorimetria de titula??o isot?rmica demonstrou que a intera??o entre Ovalbumina e Lisozima foi exot?rmica, a qual ocorreu em duas etapas, a primeira entropicamente dirigida e a segunda entalpicamente dirigida. A calorimetria diferencial de varredura sugeriu, pela presen?a de um ?nico ponto de desnatura??o, que a intera??o entre BSA e Lisozima deu origem a um novo biopol?mero com temperatura de desnatura??o a 67?C, diferente das prote?nas isoladas. Estes estudos sugeriram que complexos coacervados formados entre Ovalbumina / Lisozima e BSA / Lisozima poderiam ser utilizados como agente encapsulante de bioativos ou como ingredientes alimentares com o objetivo de agregar valor nutricional.

Orientador: Pedro Luiz Onofrio Volpe
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Mestrado
Físico-Química
Mestre em Ciências