<p>The main focus in the present work concerns calculations on steel/slag equilibria. Thermodynamic software and databases are now powerful and accurate enough to give reliable results when applied to complex metallurgical processes. One example is the decarburization process of high alloyed steels. It is shown that using advanced thermodynamic models, without a complicated kinetic description of the system, reasonable agreement with experimental data is obtained. The calculations are performed using the Thermo-Calc software.</p><p>Within this work a Java interface for Thermo-Calc has been implemented. Java gives graphical possibilities and a graphical interface has been created that facilitates calculations that involve both metallic phases as well as oxides and make them feasible also for an industrial user.</p>

Made available in DSpace on 2014-12-17T14:06:46Z (GMT). No. of bitstreams: 1 RobertoALS.pdf: 742174 bytes, checksum: d1b0bdbe4af3f236ae47837eb186d487 (MD5) Previous issue date: 2008-03-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / There are ores of clay in Piau? State that are used for red structural ceramics, which are naturally contaminated with calcareous vein. This is one thing that impedes its exploration in an adequate way, especially for tile production. The present work aims at verifying the influence of the calcareous contents in the technological structural ceramics area, seeking to determine a maximum permissible calcareous proportion/contents in the ceramic mass using the patterns of the local industry production. For the consecution of this paper, it was characterized the clay and calcareous material by FRX, DRX, TGA and DTA. It was also configurated by extrusion and burnt in the temperatures of 850?C, 900?C, 950?C and 1000?C pieces of the corpus with 0, 5, 10, 15 e 20% of calcareous proportion. After that, it was carried out technological samples of linear retraction, water absortion, apparent porosity, specific apparent mass and mechanic resistance. The results showed the possibility of using calcareous in the ceramic mass and in some cases the technological properties got better / O estado do Piau? tem jazidas de argilas utilizadas para cer?mica vermelha estrutural, que naturalmente est?o contaminadas com veios de calc?rio, o que impede a sua explora??o de forma adequada, principalmente para a produ??o de telhas. O presente trabalho tem o objetivo de verificar a influ?ncia do teor de calc?rio nas propriedades tecnol?gicas da cer?mica estrutural, visando definir um teor m?ximo de calc?rio admiss?vel na massa cer?mica utilizando-se dos padr?es de produ??o da ind?stria local. Para isso, foram caracterizadas as mat?rias-primas argila e calc?rio por FRX, DRX, TGA e DTA. Tamb?m foram conformados por extrus?o e queimados nas temperaturas de 850?C, 900?C, 950?C e 1000?C corpos-de-prova com 0%, 5%, 10%, 15% e 20% de teor de calc?rio, em seguida, realizados ensaios tecnol?gicos de retra??o linear, absor??o de ?gua, porosidade aparente, massa espec?fica aparente e resist?ncia mec?nica ? flex?o. Os resultados mostraram a possibilidade de se utilizar calc?rio na massa cer?mica, sendo que em alguns casos melhorou as propriedades tecnol?gicas

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-25T19:35:26Z No. of bitstreams: 1 SilviaAmorimTerra_DISSERT.pdf: 8312476 bytes, checksum: 1f02e20db0fedd2c8dc5413db2f0b262 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-01T20:19:56Z (GMT) No. of bitstreams: 1 SilviaAmorimTerra_DISSERT.pdf: 8312476 bytes, checksum: 1f02e20db0fedd2c8dc5413db2f0b262 (MD5) / Made available in DSpace on 2016-08-01T20:19:56Z (GMT). No. of bitstreams: 1 SilviaAmorimTerra_DISSERT.pdf: 8312476 bytes, checksum: 1f02e20db0fedd2c8dc5413db2f0b262 (MD5) Previous issue date: 2015-03-27 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / O presente trabalho objetiva a caracteriza??o de rochas carbon?ticas da Forma??o Janda?ra, termalmente afetadas no contato com intrus?es b?sicas do Pale?geno e Ne?geno, na regi?o dos munic?pios de Pedro Avelino e Janda?ra (RN), nordeste do Brasil. Para o estudo em tela, foram utilizados dados de campo, microsc?picos, difra??o de raios-X, microssonda eletr?nica e litogeoqu?mica de rocha total. Os calc?rios n?o afetados termalmente s?o wackstones, grainstones e packstones. Podem constituir fragmentos de foramin?fero bent?nico, espinhos de equinoderma, ostracode, algas, bivalve, gastr?pode, pel?ides e intraclastos. A porosidade encontrada se enquadra nos tipos vugular, intrapart?cula, interpart?cula, intercristalina e m?ldica. Como minerais essenciais, tem-se calcita, anquerita e dolomita; como fases detr?ticas, citam-se montmorilonita, pirita, limonita, quartzo e microclina. Os calc?rios termalmente afetados apresentam granula??o muito grossa a muito fina e colora??o cinza clara a escura. Os componentes fossil?feros desaparecem totalmente, e a porosidade tende a desaparecer. Com os dados obtidos, infere-se que os prot?litos carbon?ticos seriam calc?rios calc?feros a dolom?ticos, ambos com pequena quantidade de minerais do grupo das argilas. Os calc?rios cristalinos de prot?lito dolom?tico cont?m calcita rombo?drica e bastante sulfeto e ?xido / hidr?xido de ferro, tornando as rochas bem mais escuras. Os carbonatos de prot?lito calc?tico mostram grande varia??o de granula??o em fun??o do grau de recristaliza??o, que aumenta na dire??o do contato com os corpos b?sicos. Neste grupo, foram identificados os minerais pirometam?rficos lizardita e espin?lio nas amostras pouco e moderadamente afetadas, e espin?lio e espurrita nas fortemente afetadas, al?m da calcita que ocorre em todos os casos. O contexto geol?gico (intrus?es rasas de diab?sios), a presen?a dos minerais pirometam?rficos espurrita e olivina (pseudomorfisada para lizardita, serpentina, brucita), e compara??o com diagramas da literatura permitem estimar temperaturas e press?es em torno de 1050-1200?C e 0,5-1,0 kbar, respectivamente, para PTOTAL=PCO2. O resfriamento p?s-intrus?o teria propiciado a remobiliza??o de por??es de mat?ria org?nica do sedimento original e libera??o de fluidos metassom?ticos / hidrotermais, ensejando a abertura do sistema metam?rfico, com eventual contribui??o de elementos qu?micos das unidades hospedeiras (arenitos, folhelhos) e das pr?prias intrus?es b?sicas. Isto favoreceria a hidrata??o de fases pr?vias, resultando em forma??o de serpentina, clorita e brucita. Os resultados mostram a forte influ?ncia do calor aportado por intrus?es b?sicas no pacote sedimentar. Considerando que na por??o offshore da bacia ocorrem soleiras com espessura de at? 1000 m, o entendimento do pirometamorfismo poder? ser de grande utilidade na compreens?o e dimensionamento desses dep?sitos. / The present study aims the characterization of thermally affected carbonate rocks from Janda?ra Formation in contact with Paleogene and Neogene basic intrusions in the region of the Pedro Avelino and Janda?ra municipalities (RN), northeastern Brazil. For this study, field, petrographic, x-ray diffraction, electron microprobe, and whole rock litogeochemistry data of carbonates were undertaken. The thermally unaffected limestones are classified like wackstones, grainstones and packstones. They may constitute carbonates grains of benthic foraminifera, echinoderm spines, ostracods, algae, corals, bivalves, gastropods, peloids and intraclasts. The porosities are classified like vug, intraparticle, interparticle, intercrystal and moldic types. The major minerals are calcite, ankerite and dolomite; the detrital are montmorillonite, pyrite, limonite, quartz and microcline. The thermally affected limestones are very coarse to very fine-grained and light to dark gray color. The fossiliferous components totally disappear, and the porosity tends to disappear. With the data obtained, it can be inferred that the carbonate protoliths would be calciferous to dolomitic limestones, both with small amount of clay minerals. Crystalline carbonates from dolomitic protolith have rhombohedral calcite and iron oxides / hydroxides, making the rocks much darker. The carbonates from calciferous protolith have a wide variation of grain size according to the recrystallization degree, increasing toward contact with the basic bodies. In this group, it was identified the minerals lizardite and spinel in weakly to moderately affected samples, and spinel and spurrite in strongly affected rocks, as well as calcite, that occur everywhere. The geological context (shallow level diabase intrusions), the crystallization of the pyrometamorphic minerals spurrite and olivine, and comparison with diagrams from the literature allow estimating temperatures and pressures around 1050-1200 ?C and 0.5-1.0 kbar, respectively, for PTOTAL=PCO2. The post-intrusion cooling would have afforded the releasing of metasomatic / hydrothermal fluids, allowing the opening of the metamorphic system, with possible contribution of chemical elements from host units (sandstones, shales) and from basic intrusions. This would induce hydration of previous phases, allowing the formation of serpentine, chlorite and brucite. The results discussed here reveal the strong influence of the heat from basic intrusions within the sedimentary pile. Whereas in the offshore portion of the basin occur sills with up to 1000 m thickness, the understanding of pyrometamorphism might be useful for understanding and measuring the thermally affected rocks.

The assemblage of ca. 6–4 Ma volcanic rocks exposed at the Sagehen Research station in the Truckee-Tahoe region of the northern Sierra Nevada, United States, is interpreted to be, within the Ancestral Cascades volcanic arc, a Lassen-type stratovolcano complex. Sagehen is of particular importance because it is one of the few Tertiary arc volcanic centres in California which has not been heavily glaciated during the Pleistocene. The volcanic rocks are variably porphyritic or aphanitic, including abundant plagioclase with clinopyroxene and amphibole. The rocks range from basalt to basaltic-andesite to andesite in composition. Basalts are olivineand clinopyroxene-bearing with minor phenocrysts of plagioclase. The basaltic-andesites are primarily pyroxene bearing while the andesites contain pyroxene-, plagioclase- and hornblende porphyritic phases. Sagehen arc lavas are calc-alkaline and enriched in the large ion lithophile elements and depleted in High Field Strength Elements. The basalts are depleted in Zr and Hf while the andesites are enriched with Zr and Hf relative to the middle rare earth elements. Compared to previously studied Ancestral Cascade arc samples, Sagehen region basalts have lower 143Nd/144Nd isotopic values that do not correspond to proposed mantle-lithosphere mixing lines, while the andesite samples appear to represent the interplay of these two components on a 87Sr/86Sr vs. 143Nd/144Nd. The trace element data and isotopic plots suggest that the melts that produced the basalts are from subduction modified mantle wedge peridotites that ponded near the base of the lithosphere similar to the generation of other subduction related calc-alkaline lavas along convergent continental margins. The andesitic samples appear to be the result of further modification through crustal assimilation as seen in the higher isotopic Sr contents in the andesites and Ce/Smpmn vs. Tb/Ybpmn plots. Finally, the proposed map units from Sylvester & Raines (2007) were found to contain various geochemical facies based on the samples collected indicating that some map units may have to be redefined or sub-divided.

The main focus in the present work concerns calculations on steel/slag equilibria. Thermodynamic software and databases are now powerful and accurate enough to give reliable results when applied to complex metallurgical processes. One example is the decarburization process of high alloyed steels. It is shown that using advanced thermodynamic models, without a complicated kinetic description of the system, reasonable agreement with experimental data is obtained. The calculations are performed using the Thermo-Calc software. Within this work a Java interface for Thermo-Calc has been implemented. Java gives graphical possibilities and a graphical interface has been created that facilitates calculations that involve both metallic phases as well as oxides and make them feasible also for an industrial user. / QC 20101118

Haynes 282 is a gamma prime (𝛾′)-strengthened nickel base superalloy developed in 2005, exhibiting a good combination of high temperature properties and fabricability. Microstructural features such as 𝛾′ and carbides play an important role in deriving the mechanical properties of the alloy during heat treatment. As Haynes 282 is a relatively new alloy with insufficient literature availability, the present thesis is aimed at studying the evolution of microstructure for different heat treatment times and temperature with a special focus on 𝛾′ phase precipitation kinetics with different initial conditions for the material. The study is divided into two sections with objectives which are focused on the different ends to the heat-treatment time scales. The first objective of this study was to investigate γ' precipitation at short heat treatment times and develop Time-Temperature Precipitation (TTP) and Hardness (TTH) diagrams for Haynes 282 using a novel arc heat treatment. In this technique, a steady state temperature gradient, covering room temperature to liquidus, was created using stationary TIG arc on a disc mounted on a water-cooled chamber. Aged and solutionized samples were arc heat treated for 1.5 minutes, 30 minutes and 4 hours. The study was complemented with temperature modelling, thermodynamic calculations, and 𝛾′ precipitation simulation. A unique graded microstructure formed, consisting of dendritic region in fusion zone; dissolution area of all phases including MC carbides, grain boundary carbides, and 𝛾′; grain boundary carbide zone, 𝛾′ band; and base metal. 𝛾′ precipitate size increased with increasing time and temperature. 𝛾′ precipitation simulation model was developed, and it showed very good agreement with experimental results. Finally, the results were summarized in TTH and TTP diagrams. The second objective in this work was to study understand the coarsening behaviour of 𝛾′ phase with an initial pre-heat-treated GKN heat treatment using furnace heat treatment. Isothermal heat treatments for temperatures from 800°C to 1120°C and times from 30 seconds to 96 hours were performed. Morphological changes in 𝛾′ phase, particle size distribution, grain sizes and hardness on these isothermal heat-treated states are presented in this work. Additionally, A TC PRISMA precipitation model was evaluated to predict 𝛾′sizes and compare it with the measurements. It was concluded that complex initial microstructure, containing bimodal distribution of 𝛾′ precipitates, caused deviations between predicted and measured values, while the model, in the previous objective, predicted the sizes in close approximation to the experimental values. Therefore, further understanding and development of precipitation kinetics with the software should be done to achieve closer results to the experiment. / Haynes 282 är ett gamma prime (𝛾′) - förstärkt superlegering av nickelbas som utvecklades 2005 och uppvisar en god kombination av högtemperaturegenskaper och tygbarhet. Mikrostrukturella egenskaper såsom 𝛾′ och karbider spelar en viktig roll för att få de mekaniska egenskaperna hos legeringen under värmebehandling. Eftersom Haynes 282 är en relativt ny legering med otillräcklig litteraturtillgänglighet syftar den aktuella avhandlingen till att studera utvecklingen av mikrostruktur för olika värmebehandlingstider och temperatur med ett särskilt fokus på 𝛾′ fasutfällningskinetik med olika initiala förhållanden för materialet. Studien är uppdelad i två sektioner med mål som är inriktade på de olika ändarna på värmebehandlings tidsskalorna. Det första syftet med denna studie var att undersöka 𝛾′nederbörd vid korta värmebehandlingstider och utveckla Time-Temperature Precipitation (TTP) och Hardness (TTH) diagram för Haynes 282 med användning av en ny bågvärmebehandling. I denna teknik skapades en jämn temperaturgradient, som täcker rumstemperatur till liquidus, med användning av stationär TIG-båge på en skiva monterad på en vattenkyld kammare. Åldriga och lösningsbara prover bågvärmebehandlades under 1,5 minuter, 30 minuter och 4 timmar. Studien kompletterades med temperaturmodellering, termodynamiska beräkningar och 𝛾′utfällningssimulering. En unik graderad mikrostruktur bildad, bestående av dendritisk region i fusionszon; upplösningsområde för alla faser inklusive MC-karbider, korngränsande karbider och 𝛾′; korngränsen karbidzon, 𝛾′ band; och oädel metall. 𝛾′utfällningsstorlek ökade med ökande tid och temperatur. 𝛾′utfällningssimuleringsmodell utvecklades, och den visade mycket bra överensstämmelse med experimentella resultat. Slutligen sammanfattades resultaten i TTH- och TTP-diagram. Det andra syftet med detta arbete var att studera förstå det förgrovning beteendemönster hos 𝛾′ fasen med en initial förvärmebehandlad GKN-värmebehandling med ugnsvärmebehandling. Isotermiska värmebehandlingar för temperaturer från 800 ° C till 1120 ° C och gånger från 30 sekunder till 96 timmar utfördes. Morfologiska förändringar i 𝛾′fasen, partikelstorleksfördelning, kornstorlekar och hårdhet på dessa isotermiska värmebehandlade tillstånd presenteras i detta arbete. Dessutom utvärderades en TC PRISMA-nederbördsmodell för att förutsäga 𝛾′ storlekar och jämföra den med mätningarna. Det drogs slutsatsen att komplex initial mikrostruktur, innehållande bimodal fördelning av 𝛾′-fällningar, orsakade avvikelser mellan förutspådda och uppmätta värden, medan modellen i det tidigare målet förutspådde storleken i nära anpassning till experimentvärdena. Därför bör ytterligare förståelse och utveckling av utfällningskinetik med programvaran göras för att uppnå närmare resultat till experimentet.

This project is a feasibility study for Hydro Extrusion Sweden AB, a company that produces extruded aluminium profiles. The main purpose of this project was to analyse the difference of Mg2Si particle sizes in aluminium alloys when varying parameters, such as cooling rate and composition, in aluminium extrusion, particularly the EN AW 6082 alloy. The Mg2Si particles have a great impact on the product’s mechanical properties. This was done in order to investigate whether real-time process parameter control is possible or not. The main software used was Thermo-Calc and the add-on module DICTRA. Thermo-Calc was used to do equilibrium calculations and gather data for the alloy and its phases. Based on this information and data from Hydro, simulations in DICTRA could be performed. The results were then plotted with respect to time and radius. The findings indicate that the cooling rate significantly influences the particle size. As the process becomes more intricate and involves a greater number of trace elements, adjusting the cooling rate could potentially be employed as a means to address this issue. The results also showed that trace elements had a minimal effect on the particle size. However, this probably does not match the reality since other phases affect and block the growth of Mg2Si.The overall results indicate a positive outcome for using DICTRA in determining particle sizes. However, further research needs to be done in correlation with more experiments before this could be a viable research method for Hydro. / Det här projektet är en förstudie för företaget Hydro Extrusion Sweden AB som producerar extruderade aluminiumprofiler. Det huvudsakliga syftet med projektet var att analysera skillnaden på Mg2Si-partiklarnas storlek i aluminiumlegeringar när olika parametrar som kylhastighet och sammansättning användes vid aluminiumextrudering, mer specifikt legeringen EN AW 6082. Mg2Si partiklarna har stor betydelse för produktens mekaniska egenskaper. Syftet med detta var att undersöka huruvida det är möjligt att styra process parametrarna i realtid. Mjukvaran som användes var Thermo-Calc och tilläggsmodulen DICTRA. Thermo-Calc användes för att göra jämviktsberäkningar och samla in data för legeringen samt dess faser. Baserat på denna information och data från Hydro kunde simuleringar i DICTRA utföras. Resultaten plottades sedan med avseende på tid och radie. Partikelstorleken påverkas avsevärt av kylningshastigheten enligt resultaten. I framtiden, när processen blir mer avancerad med fler spårämnen, kan det vara möjligt att justera kylningshastigheten för att hantera detta. Resultaten visade också att spårämnen hade en mycket liten effekt på partikelstorleken. Detta stämmer dock förmodligen inte med verkligheten eftersom andra faser påverkar och blockerar tillväxten av Mg2Si. De övergripande resultaten pekar på ett positivt resultat för att använda DICTRA för att bestämma partikelstorlekar. Ytterligare forskning måste göras i samband med fler experiment innan detta kan vara en genomförbar forskningsmetod för Hydro.

A stanniocalcina-1 (STC1) é uma glicoproteína caracterizada como um fator endócrino com ação anti-hipercalcêmica/hipocalcêmica originalmente descoberta em peixes. Em mamíferos, esse hormônio está expresso em praticamente todos os tecidos, regula diversas funções biológicas e atua como um fator autócrino/ parácrino. Diversas evidências demonstram o envolvimento da STC1 no desenvolvimento ósseo. Durante a embriogênese, a STC1 é expressa nos primeiros estágios de condensação mesenquimal e, posteriormente, se mantém restrita a preosteoblastos e osteoblastos maduros. Além disso, a STC1 estimula a mineralização óssea através do aumento da expressão de transportadores de fosfato e da osteopontina, uma sialoglicoproteína que atua na mineralização óssea. Células-tronco adultas simbolizam atualmente a fonte mais acessível de células progenitoras utilizadas em terapias celulares e engenharia de tecidos. O tecido adiposo contém uma população de células biológica e clinicamente interessantes denominada células tronco adiposo derivadas (CTADs). Atualmente as CTADs são a melhor fonte de células tronco adultas podendo ser obtidas através de procedimentos minimamente invasivos. Um grande número de estudos têm demonstrado o potencial osteogênico dessas células, no entanto, ainda é um desafio a compreensão dos mecanismos envolvidos na diferenciação osteogênica a partir das CTADs. Neste estudo, foi demonstrado que sete dias de indução osteogênica das CTADs na presença de 50 ng/mL de STC1 aumentaram significativamente a expressão gênica e proteica dos marcadores osteogênicos: fosfatase alcalina (FA), runt related gene 2 (RUNX2) e osteopontina (OPN) O aumento na atividade da enzima FAS foi relacionado diretamente com a maior expressão gênica e proteica. Além disso, a STC1 modula a via de sinalização pAKt/pGSK3-β/βcatenina em preosteoblastos de 7 dias sugerindo que seus efeitos sobre a osteogênese sejam mediados por essa via de sinalização. O peptídeo neuroendócrino CGRP (peptídeo relacionado ao gene da calcitonina) possui similaridades com STC1 e desempenha um importante papel nas fases iniciais da diferenciação dos osteoblastos. O CGRP ativa o receptor CALCRL, formando um dímero com a proteína transmembrana acessória RAMP1. Para elucidar o envolvimento da STC1 nas vias de sinalização relacionadas a receptores de calcitonina foi investigado o efeito desse hormônio na modulação 8 do receptor do CGRP e receptor de calcitonina (CTR) em CTADs diferenciadas para preosteoblastos e células Hek 293 superexpressoras de CALCRL/RAMP1 e CTR. A STC1 não alterou a expressão dos genes CALCRL e ramp1 durante a osteoblastogênese mas provocou alterações na distribuição espacial do complexo CALCRL/RAMP1 na membrana plasmática de preosteoblastos, induzindo a formação de clusters Além do efeito sobre a sinalização do CGRP a STC1 demonstrou inibir a sinalização da calcitonina diminuindo a produção de cAMP em células transfectadas com CTR. A STC1 não alterou os níveis intracelulares de cálcio e ATP. Esses resultados indicam que, embora não atue diretamente via os receptores CALCRL/RAMP1 e CTR, a STC1 modula a sinalização dos peptídeos CGRP e CT. Estudos mais detalhados sobre os efeitos da STC1 nas diferentes vias de sinalização são necessários para desvendar completamente os mecanismos de diferenciação osteogênicos das CTADs estimuladas por esse hormônio. / The stanniocalcin-1 (STC1) is a glycoprotein characterized as an endocrine factor with anti-hypercalcemic / hypocalcemic action, originally identified in fish. The hormone in mammals is expressed in virtually all tissues and regulates diverse biological functions, acting as an autocrine / paracrine factor. Many evidences demonstrate that STC1 is able to regulate bone development. During embryogenesis the STC1 is expressed in early stages of mesenchymal condensation and thereafter remains restricted to preosteoblast and mature osteoblast. Furthermore, STC1 stimulates bone mineralization by increasing the phosphate transporter expression and osteopontin, a sialoglycoprotein involved in bone mineralization. Adult stem cells currently symbolize the most accessible source of stem cells used in cell therapy and tissue engineering. Adipose tissue contains a population of biological cells clinically interesting called adipose derived stem cells (ASC). Currently, the ASCs are the best source of adult stem cells and can be harvested using minimally invasive procedures. A large number of studies had shown osteogenic potential of these cells, however, it is still a challenge to understand the mechanisms involved in osteogenic differentiation from ASCs This study demonstrated that 7-day preosteoblast in the presence of 50 ng / ml STC1 significantly increased gene and protein expression of osteogenic markers: alkaline phosphatase (ALP), runt related gene 2 (RUNX2), and osteopontin (OPN ). Also, there was an increase in the enzymatic activity of the ALP, possibly related to both gene and protein expression. Furthermore, STC1 modulates pAkt / pGSK3-β / βcatenina signaling in 7-day preosteoblast, suggesting that the STC1 effects on the osteogenesis is mediated by this pathway. The neuroendocrine peptide CGRP (calcitonin gene related peptide) has similarities to STC1 and plays an important role in the early stages of osteoblast differentiation. The active CGRP receptor form a dimer with the receptor activity-modifying protein 1 (RAMP1). To elucidate the involvement of STC1 in signaling pathways related to calcitonin receptors, it was investigated the STC1 effect on peptide receptor modulating the calcitonin gene related peptide (CGRP) and the calcitonin receptor (CTR) in 7-day preosteoblast, and in Hek 293 cells transfected with CALCRL / RAMP1 and CTR The STC1 did not change the expression of genes CALCRL and ramp1 during osteoblastogenesis but modified the plasma membrane spatial distribution of 10 CALCRL/RAMP1 in preosteoblast. Besides the effect on CGRP signaling, STC1 inhibited the calcitonin signaling by decreasing cAMP production in cells transfected with CTR. The STC1 did not alter intracellular calcium levels and ATP. These results indicated that STC1 does not act on the same receptors for calcitonin and CGRP, but modulates the action of these peptides. Studies on the effects of STC1 in different signaling pathways are necessary for understanding the mechanisms underlying the STC1 ability in enhancing osteoblastogenesis from hASCs.

Made available in DSpace on 2014-12-17T15:42:08Z (GMT). No. of bitstreams: 1 GilianeCMNS_DISSERT.pdf: 1750841 bytes, checksum: cedbb003a4fc658825db6f8e66611748 (MD5) Previous issue date: 2013-06-25 / In this research the removal of light and heavy oil from disintegrated limestone was investigated with use of microemulsions. These chemical systems were composed by surfactant, cosurfactant, oil phase and aqueous phase. In the studied systems, three points in the water -rich microemulsion region of the phase diagrams were used in oil removal experiments. These microemulsion systems were characterized to evaluate the influence of particle size, surface tension, density and viscosity in micellar stability and to understand how the physical properties can influence the oil recovery process. The limestone rock sample was characterized by thermogravimetry, BET area, scanning electron microscopy and X-ray fluorescence. After preparation, the rock was placed in contact with light and heavy oil solutions to allow oil adsorption. The removal tests were performed to evaluate the influence of contact time (1 minute, 30 minutes, 60 minutes and 120 minutes), the concentration of active matter (20, 30 and 40 %), different cosurfactants and different oil phases. For the heavy oil, the best result was on SME 1, with 20 % of active matter, 1 minute of contact time, with efficiency of 93,33 %. For the light oil, also the SME 1, with 20 % of active matter, 120 minutes of contact time, with 62,38 % of efficiency. From the obtained results, it was possible to conclude that microemulsions can be considered as efficient chemical systems for oil removal from limestone formations / O presente trabalho objetivou estudar a remo??o de fra??es de ?leo leve e pesado em rocha calc?ria desintegrada atrav?s de sistemas microemulsionados, comparando as efici?ncias de remo??o em diferentes concentra??es de mat?ria ativa (C/T) e tempo de contato. Os sistemas microemulsionados (SME) s?o constitu?dos por tensoativo, cotensoativo, fase oleosa e fase aquosa. Nos sistemas estudados, tr?s pontos ricos em ?gua da regi?o de microemuls?o foram utilizados para verificar a efici?ncia de remo??o. Os sistemas foram caracterizados para avaliar a influ?ncia do tamanho do agregado, tens?o superficial e viscosidade na estabilidade micelar e compreender como as propriedades f?sicas podem influenciar o processo de remo??o de ?leo. A amostra de rocha calc?ria foi caracterizada por Termogravimetria, ?rea BET, Microscopia Eletr?nica de Varredura, Difra??o de Raios-X e Fluoresc?ncia de Raios-X. A rocha preparada foi colocada em contato com solu??o de ?leo leve e pesado em xileno para permitir a adsor??o de ?leo. Os testes de remo??o foram realizados a fim de avaliar a influ?ncia do tempo de contato (1, 30, 60 e 120 minutos), da concentra??o de mat?ria ativa (20, 30 e 40%), do cotensoativo e da fase oleosa. Para o ?leo pesado, o melhor resultado foi para o SME 1, com 20 % de mat?ria ativa, no tempo de 1 minuto, com 93,33 % de efici?ncia. Para o ?leo leve, o SME 1 no percentual de 20 %, com 120 minutos apresentou o melhor rendimento, com 62,38 %. A partir dos resultados obtidos, concluiu-se que os sistemas microemulsionados apresentam-se como uma alternativa eficaz para remo??o de ?leo em forma??es calc?rias

For many decades zirconium alloys have been commonly used in the nuclear power industry as fuel cladding material. Besides their good corrosion resistance and acceptable mechanical properties the main reason for using these alloys is the low neutron absorption. Zirconium alloys are exposed to a very severe environment during the nuclear fission process and there is a demand for better design of this material. To meet this requirement a thermodynamic database is useful to support material designers. In this thesis some aspects of the development of a thermodynamic database for zirconium alloys are presented. A thermodynamic database represents an important facility in applying thermodynamic equilibrium calculations for a given material providing: 1) relevant information about the thermodynamic properties of the alloys e.g. amount and composition of phases, oxygen activity, heat capacity etc, and 2) significant information for the manufacturing process e.g. heat treatment temperature. The basic information in the database is first the unary data, i.e. pure elements; those are taken from the compilation of the Scientific Group Thermodata Europe (SGTE) and then the binary and ternary systems. All phases present in those binary and ternary systems are described by means of the Gibbs energy as a function of composition and temperature. Many of those binary systems have been taken from published or unpublished works and others have been assessed in the present work. The elements included in the databse are: C, Fe, Cr, Nb, Ni, Mo, O, Si, Sn, and Zr + H, and the assessment performed under this thesis are: Cr-Sn, Mo-Zr, Sn-Zr, Fe-Nb-Zr and Nb-O-Zr. All the calculations have been made using Thermo-Calc software and the representation of the Gibbs energy obtained by applying Calphad technique with some use of ab initio calculations. / QC 20100902