Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-05-28T12:17:14Z No. of bitstreams: 1 469509 - Texto Completo.pdf: 1433319 bytes, checksum: 69adb0d2b5f0bd949fea8c36366fca5a (MD5) / Made available in DSpace on 2015-05-28T12:17:14Z (GMT). No. of bitstreams: 1 469509 - Texto Completo.pdf: 1433319 bytes, checksum: 69adb0d2b5f0bd949fea8c36366fca5a (MD5) Previous issue date: 2015-03-02 / Background: Adequate control of extracellular volume is a major goal of hemodialysis (HD) in chronic kidney disease (CKD) patients. Fluid overload contributes significantly to the high morbidity and mortality rates of these patients. The body composition monitor by multifrequency bioimpedance (BCM) is equipment tool able to quantify objectively and accurately the hydration status of each patient. The aim of this study was to compare the efficacy between bioelectrical impedance analysis (BIA) and clinical evaluation to adjust dry weight (DW) in HD patients. Methods: A randomized crossover study. Patients were randomized in two groups: A, in which patients were evaluated by the clinical evaluation and B, wherein the dry weight of the patients was assessed by BIA, for four weeks. Following a wash-out period a crossover between the groups was performed and patients observed for 1 month. The study was approved by the ethics committee of Pontificia Cat?lica University of Rio Grande do Sul. Results: The study included 57 CKD in HD. Blood pressure, hydration parameters and DW were not significantly different between the groups indicating an equivalence between BIA and clinical evaluation treatments to determine DW in HD. Conclusion: The study shows that the BIA is similar than the clinical evaluation to guide ultrafiltration and determine DW in HD. / Introdu??o: O controle adequado do volume extracelular ? um dos principais objetivos da terapia renal substitutiva (TRS) em doentes renais cr?nicos (DRC), pois a sobrecarga h?drica contribui com as altas taxas de morbimortalidade destes pacientes. O monitor de composi??o corporal por bioimped?ncia multifrequencial (BCM) ? um equipamento capaz de quantificar de maneira objetiva o estado de hidrata??o de cada paciente, visando avaliar o peso seco (PS). O objetivo desse estudo foi comparar a efic?cia entre an?lise por bioimped?ncia el?trica (BIA) e avalia??o cl?nica (AC) para adequa??o de PS em pacientes em hemodi?lise (HD). M?todo: Estudo randomizado, do tipo crossover. Os pacientes foram randomizados em dois grupos: A, iniciou o estudo com o PS sendo determinado por AC e B, por BIA, por 1 m?s. Ap?s, foi realizado o cruzamento dos grupos e invers?o dos tratamentos, por mais 1 m?s. O estudo foi aprovado pelo comit? de ?tica da Pontif?cia Universidade Cat?lica do Rio Grande do Sul. Resultados: Participaram do estudo 57 DRC em HD. Comparando os dois tratamentos para dados de press?o arterial, par?metros de hidrata??o e PS, independente dos grupos, os resultados n?o detectaram diferen?as significativas, apontando uma equival?ncia entre os tratamentos de BIA e AC para determinar PS em HD. Conclus?o: Estudo demonstra que a BIA ? equivalente ? AC para guiar a ultrafiltra??o e determinar PS em HD.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-04-04T12:33:17Z No. of bitstreams: 1 2016 - V?vian Palheta da Rocha 2016.pdf: 925358 bytes, checksum: 56f81d180a908791a6be805b35fee76f (MD5) / Made available in DSpace on 2017-04-04T12:33:17Z (GMT). No. of bitstreams: 1 2016 - V?vian Palheta da Rocha 2016.pdf: 925358 bytes, checksum: 56f81d180a908791a6be805b35fee76f (MD5) Previous issue date: 2016-03-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The crambe (Crambe abyssinicaHochst) has been cultivated because of its potential in the production of oil in its seeds, as fodder plant, among other uses. For this species, the high oil content affects the storage potential of seeds and associated with factors such as the pericarp, low availability of water in the soil can provide uneven germination. So, to reduce the nega-tive effects of the factors thatinterfere with crambe seed germination, it can be through the use of priming techniques. The objective of this research was to evaluate the efficiency of priming techniques in physiological quality of crambe seeds stored under controlled condi-tions. Therefore, the experiment was conducted in 2015 to 2016 period for crambe, classified seeds were used, treated, packed in paper bags krafts. After zero, three and six months of stor-age, the seeds were submitted to physiological primingtechniques, using the unmonitored hydration techniques (immersion in water), matriosmopriming with PEG 6000 -0.2 MPa, moist atmosphere and matripriming. Unconditioned seeds were used as control. The seeds were evaluated after drying by germination and vigor (first count, seedling performance, seedling emergence and electrical conductivity). From the results it can be concluded that the seeds subjected to matriosmoprimingand matriprimingpresent approximately 40% water content after 8 hours of imbibition. There was favoring the germination of seeds and dry mass of lot 1 after they have been submitted to matriosmoprimingat 0, three and six months. There was an increase of germination rate of seeds lot 3 which were submitted to matriprimingthe three and six months of storage. / O crambe (Crambe abyssinica Hochst) tem sido cultivado devido ao seu potencial na produ??o de ?leo em suas sementes e, como planta forrageira, entre outros usos. Para esta esp?cie, o alto teor de ?leo prejudica o potencial de armazenamento de suas sementes, assim como o uso de sementes com a presen?a do pericarpo do fruto no momento da semeadura ea baixa dispo-nibilidade de ?gua no solo podem proporcionar germina??o desuniforme. Para reduzir os efeitos negativos dos fatores que interferem no desempenho de sementes de crambe, pode ser em-pregado o condicionamento fisiol?gico das sementes. Assim, o objetivo desta pesquisa foi avaliar a efici?ncia de diferentes t?cnicas de condicionamento fisiol?gico na qualidade fisio-l?gica das sementes de crambe armazenadas em condi??es controladas. Para tanto, o experi-mento foi realizado no per?odo de 2015 a 2016. Sementes classificadas, tratadas e acondicio-nadas em sacos de papel foram avaliadas ap?s zero, tr?s e seis meses de armazenamento. As sementes foram submetidas ?s t?cnicas de hidrata??o n?o monitorada (imers?o em ?gua), matriosmocondicionamento com PEG 6000 a -0,2 MPa, atmosfera ?mida e matricondicionamento. Sementes n?o condicionadas foram utilizadas como controle. As sementes foram avaliadas ap?s secagem pelos testes de germina??o e vigor (primeira contagem, desempenho de pl?ntulas, emerg?ncia de pl?ntulas e condutividade el?trica). Pelos resultados, pode-se concluir que as sementes submetidas ao matriosmocondicionamento e ao matricondicionamento apresen-tam em torno de 40% de teor de ?gua ap?s 8 horas de embebi??o. Houve favorecimento da germina??o das sementes e da massa seca das pl?ntulas do lote 1 ap?s terem sido submetidas ao matriosmocondicionamento, aos zero , tr?s e seis meses. O matricondicionamento favoreceu a velocidade de germina??o das sementes do lote 3, aos tr?s e seis meses de armazenamento.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-06-02T21:45:30Z No. of bitstreams: 1 StellaMariaAndradeGomesBarreto_DISSERT.pdf: 2589598 bytes, checksum: eb867f2ecba9f71b559518fcc2a0d571 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-06-07T20:58:36Z (GMT) No. of bitstreams: 1 StellaMariaAndradeGomesBarreto_DISSERT.pdf: 2589598 bytes, checksum: eb867f2ecba9f71b559518fcc2a0d571 (MD5) / Made available in DSpace on 2017-06-07T20:58:36Z (GMT). No. of bitstreams: 1 StellaMariaAndradeGomesBarreto_DISSERT.pdf: 2589598 bytes, checksum: eb867f2ecba9f71b559518fcc2a0d571 (MD5) Previous issue date: 2017-03-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O beneficiamento das folhas de Agave sisalana fornece a fibra, com valor agregado para a ind?stria de sisal, e o restante do material vegetal, denominado de subproduto, que ? descartado, gera impacto ambiental. Diferentes aplica??es t?m sido atribu?das, no entanto, n?o existem pesquisas cient?ficas que apontem a utiliza??o deste subproduto como mat?ria-prima cosm?tica. O objetivo dessa pesquisa foi obter e caracterizar uma fra??o enriquecida em polissacar?deos (FrE) a partir do subproduto de Agave sisalana, avaliar a seguran?a in vitro e in vivo, bem como a atividade antioxidante in vitro, e, ent?o, desenvolver uma nanoemuls?o hidratante. A partir da por??o l?quida do subproduto foram obtidos o extrato bruto (EB) e duas fra??es. O EB e as fra??es foram avaliados quanto ? presen?a de a??cares, prote?nas e polifenois. A seguran?a foi avaliada por meio dos testes de citotoxicidade e fototoxicidade in vitro utilizando o m?todo colorim?trico do vermelho neutro. A irritabilidade prim?ria foi verificada pelo teste de contato (patch test). A capacidade antioxidante foi avaliada pelos m?todos de sequestro de DPPH e molibd?nio. Diferentes sistemas foram obtidos por meio de pseudodiagrama tern?rio, aditivados ou n?o com 0,5% de FrE. As formula??es selecionadas foram submetidas aos testes de estabilidade preliminar e acelerada por um per?odo de 90 dias. A efic?cia hidratante foi avaliada quanto ao conte?do h?drico do estrato c?rneo e quanto ? perda de ?gua transepidermal por um per?odo de 5 horas. As amostras apresentaram, como constituintes qu?micos, a??cares, polifenois e prote?nas. A FrE n?o apresentou potencial citot?xico ou fotot?xico, n?o foi irritante e pode ser considerada um ativo com propriedade antioxidante. Nanoemuls?es est?veis contendo 40% de fase oleosa, 10% de tensoativos e 50% de fase aquosa foram obtidas. A nanoemuls?o foi capaz de aumentar significativamente o conte?do h?drico e manter a fun??o de barreira da pele ap?s 5h de uma ?nica aplica??o. A fra??o obtida do subproduto industrial de Agave sisalana apresenta um perfil promissor como mat?ria-prima cosm?tica para cuidado da pele com capacidade antioxidante e hidratante, em conjunto com a possibilidade de agregar valor ao res?duo industrial, reduzindo os danos provocados ao meio ambiente pelo descarte desse material. / The processing of the leaves of Agave sisalana provides fiber, with added value for the sisal industry, and the rest of the plant material, known as by-product, is thrown and generates environmental impact. Different applications have been attributed, however, there are no scientific researches that aim to use this product as a cosmetic raw material. The objective of this research was to obtain and characterize polysaccharides-enriched fraction (FrE) from the Agave sisalana by-product of, assess the safety in vitro and in vivo, as well as to evaluate the antioxidant activity in vitro, and then to develop a nanoemulsion with moisturizer effect. From the liquid portion of the by-product obtained the crude extract (EB) and two fractions resulting from extractive process. The EB and the fractions were evaluated for the presence of sugars, proteins and polyphenols. Safety was evaluated by cytotoxicity and phototoxicity in vitro assays using the colorimetric method of Neutral Red. Irritability was evaluated by the primary contact test (patch test). The antioxidant capacity was assessed using the DPPH scavenging tests and molybdenum method. Different systems were obtained by means of pseduodiagrama ternary containing, or not, 0.5% FrE. The selected formulations were submitted to preliminary stability tests and accelerated in different temperatures conditions for a period of 90 days. The moisturizing efficacy was evaluated by water content of the stratum corneum and transepidermal water loss for a period of 5 hours. The samples presented as chemical constituents, sugars, polyphenols and proteins. The FrE showed no phototoxic potential or cytotoxic, and was not irritating to skin of volunteers and can be considered an asset with antioxidant property Nanoemulsion containing 40% oil phase, 50% aqueous phase and 10% surfactants was stable for 90 days.The nanoemulsion was able to significantly increase the water content and maintain skin barrier function after 5 hours from a single application. The fraction obtained from the industrial by-product of Agave sisalana demonstrated a promising profile as raw material for cosmetic skin care with moisturizing and antioxidant capacity, together with the possibility of adding value to industrial waste, reducing the damage caused to the environment by disposing of this material.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-11-12T14:44:33Z No. of bitstreams: 1 GabrielAzevedoDeBritoDamasceno_DISSERT.pdf: 1484595 bytes, checksum: 579485d8825b9a642a20df91ae7b7fcc (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2015-11-16T12:38:53Z (GMT) No. of bitstreams: 1 GabrielAzevedoDeBritoDamasceno_DISSERT.pdf: 1484595 bytes, checksum: 579485d8825b9a642a20df91ae7b7fcc (MD5) / Made available in DSpace on 2015-11-16T12:38:53Z (GMT). No. of bitstreams: 1 GabrielAzevedoDeBritoDamasceno_DISSERT.pdf: 1484595 bytes, checksum: 579485d8825b9a642a20df91ae7b7fcc (MD5) Previous issue date: 2014-03-28 / A esp?cie Opuntia f?cus-indica (L.) Mill ? uma cact?cea pertencente ao ecossistema Caatinga e apresenta em sua composi??o qu?mica flavonoides, ?cido galactur?nico e a??cares. Foram desenvolvidos diferentes extratos vegetais hidroglic?licos (EHG001 e EHG002) e hidroetan?licos posteriormente liofilizados (EHE001 e EHE002), dentro os quais o EHE002 teve sua composi??o fitoqu?mica preliminar investigada por cromatografia em camada delgada e observada a predomin?ncia de flavonoides. Foram preparadas diferentes formula??es na forma de emuls?es com o Sodium Polyacrylate (and) Hydrogenated Polydecene (and) Trideceth-6 (Rapithix? A60) e com o Polyacrylamide (and) C13-14 Isoparaffin (and) Laureth-7 (Sepigel? 305) e em gel com o Sodium Polyacrylate (Rapithix? A100). O estudo de avalia??o sensorial foi realizado utilizando a metodologia check-all-thatapply. N?o foram verificadas diferen?as significativas entre as notas atribu?das ?s formula??es, por?m, foi observada prefer?ncia pelas formuladas com o 1,5% de Rapithix? A100 e com 3,0% de Sepigel? 305. Essas e a formula??o com 3% de Rapithix? A60 foram aditivadas com 1% do extrato hidroglic?lico (EHG001) e submetidas aos testes de estabilidades preliminar e acelerada. No estudo de estabilidade acelerada, as amostras foram estocadas em diferentes temperaturas durante 90 dias. As caracter?sticas organol?pticas, determina??o do valor de pH e comportamento reol?gico foram avaliados. Ao final do estudo, as emuls?es com 3,0% de Sepigel? 305 e 3% de Rapithix? A60 foram consideradas est?veis com caracter?sticas pseudopl?sticas e tixotr?picas. A efic?cia cl?nica hidratante das formula??es contendo 3,0% de Sepigel? 305 aditivadas com 1 e 3% do EHG001 foi realizada por meio do m?todo da capacit?ncia (Corneometer?) e da avalia??o da perda de ?gua transepidermal - TEWL (Tewameter?). Observou-se que a formula??o com 3% do EHG001 apresentou efic?cia hidratante frente ao ve?culo e ao solvente extrator ap?s 5 horas e as emuls?es contendo 1 e 3% do extrato apresentaram efeito barreira at? 4 horas reduzindo a perda de ?gua transepidermal. / Opuntia f?cus - indica (L.) Mill is a cactacea presents in the Caatinga ecosystem and shows in its chemical c omposition flavonoids, galacturonic acid and sugars. Different hydroglicolic (EHG001 and EHG002) and hydroethanolic subsequently lyophilized (EHE001 and EHE002) extracts were developed. The EHE002 had his preliminary phytochemical composition investigated by thin layer chromatography (TLC) and we observed the predominance of flavonoids. Different formulations were prepared as emulsions with Sodium Polyacrylate (and) Hydrogenated Polydecene (and) Trideceth - 6 (Rapithix? A60), and Polyacrylamide (and) C13 - 14 I soparaffin (and) Laureth - 7 (Sepigel? 305), and gel with Sodium Polyacrylate (Rapithix? A100). The sensorial evaluation was conducted by check - all - that - apply method. There were no significant differences between the scores assigned to the formulations, howe ver, we noted a preference for those formulated with 1,5% of Rapithix? A100 and 3,0% of Sepigel? 305. These and the formulation with 3% Rapithix? A60 were tested for preliminary and accelerated stability. In accelerated stability study, samples were stored at different temperatures for 90 days. Organoleptic characteristics, the pH values and rheological behavior were assessed. T he emulsions formulated with 3,0% of Sepigel? 305 and 1,5% of Rapithix? A60 w ere stable with pseudoplastic and thixotropic behavior . The moisturizing clinical efficacy of the emulsions containing 3,0% of Sepigel? 305 containing 1 and 3% of EHG001 was performed using the capacitance method (Corneometer?) and transepidermal water lost ? TEWL evaluation ( Tewameter?). The results showed t hat the formulation with 3% of EHG001 increased the skin moisturizing against the vehicle and the extractor solvent formulation after five hours. The formulations containing 1 and 3% of EHG001 increased skin barrier effect by reducing transepidermal water loss up to four hours after application.

Made available in DSpace on 2014-12-17T15:41:44Z (GMT). No. of bitstreams: 1 EmanuellaLFV.pdf: 2331935 bytes, checksum: 3f4df9b602349e41bf8ab4d2c561b59d (MD5) Previous issue date: 2009-01-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The clay swelling is today one of the major problems during the well drilling. Nearly 50% of clays that constitute shale expand easily in the presence of water molecules. During the drilling of a geological formation containing swelling clays, when is feasible the use of water base fluids, it is necessary to apply clay inhibitors. This avoids the incorporation of the cutting to the drilling fluid which is responsible for the wall swelling and crumbling. The aim of this work was to evaluate the synergistic behavior that occurs when swelling clay inhibitors are associated to NaCl and KCl salts. Three swelling clay inhibitors samples, INIB A, INIB B and INIB C, were analyzed. Each inhibitor was characterized by the amount of chlorides and active matter content. For the water-clay interaction evaluation in the presence of various fluids, it was used the Capillary Suction Timer (CST, Fann) and Linear Swell Meter (LSM 2000, Fann). For better interpretation of results, a Design of Experiments (DOE, Umetrics MODDE 7.0 TM) through Result Surface Methodology (RSM) was employed, taking into account the type, the swelling inhibitors concentration and the contact time with the clay. The results showed different efficiencies among the inhibitors employed, and the salt-inhibitors mixtures were more efficient than those products alone. However, for field operation, other parameters should be taking into account, as operational cost, environmental requests and time of application for each product / O inchamento das argilas, quando em contato com o fluido de perfura??o, tem sido um dos maiores vil?es na perfura??o de po?os de petr?leo. Aproximadamente 50 % das argilas que constituem um folhelho se expandem facilmente na presen?a de mol?culas de ?gua. Na perfura??o de camadas geol?gicas contendo folhelhos hidrat?veis, quando ? vi?vel a utiliza??o de fluidos ? base de ?gua, h? a necessidade de utiliza??o de inibidores de inchamento de argilas. Estes inibidores evitam que os s?lidos perfurados incorporem-se ao fluido, e impedem o inchamento e o desmoronamento das paredes dos po?os. Esta disserta??o teve como objetivo realizar um estudo sobre o comportamento sinerg?tico de inibidores de hidrata??o de argila quando associados aos sais de NaCl e KCl. Foram analisadas tr?s amostras de inibidores de inchamento de argila comerciais, INIB A, INIB B e INIB C. Cada inibidor foi caracterizado quanto ao teor de cloreto e de mat?ria ativa. Para avalia??o da intera??o ?gua-argila na presen?a dos diversos fluidos, amostras de argila ativada foram submetidas a testes de capilaridade no CST (Capilary Succion Timer) e de inchamento no LSM (Linear Swell Meter). Para melhor interpreta??o dos resultados, foi empregada an?lise estat?stica experimental (DOE), por metodologia de resposta de superf?cie (RSM), atrav?s do programa MODDE 7.0TM da Umetrics, em que se levou em considera??o o tipo, a concentra??o dos inibidores de inchamento e o tempo de contato com a argila. A an?lise dos resultados comprovou as diferen?as de efici?ncia entre os inibidores empregados e que misturas dos inibidores com sais s?o mais eficientes que os produtos individualmente. Entretanto, para opera??es de campo, outros par?metros devem ser levados em considera??o, tais como custo, exig?ncias dos ?rg?os ambientais e tempo de atua??o do produto

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-02-21T21:14:12Z No. of bitstreams: 1 BrunoLeonardoDeSenaCosta_TESE.pdf: 4089487 bytes, checksum: fcfd3987ed1c7e1dfaa97685067e032e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-02-22T20:55:45Z (GMT) No. of bitstreams: 1 BrunoLeonardoDeSenaCosta_TESE.pdf: 4089487 bytes, checksum: fcfd3987ed1c7e1dfaa97685067e032e (MD5) / Made available in DSpace on 2018-02-22T20:55:45Z (GMT). No. of bitstreams: 1 BrunoLeonardoDeSenaCosta_TESE.pdf: 4089487 bytes, checksum: fcfd3987ed1c7e1dfaa97685067e032e (MD5) Previous issue date: 2018-01-15 / Neste trabalho o fen?meno da carbonata??o do cimento Portland ? investigado por diferentes abordagens, por?m convergindo para o mesmo objetivo: aprofundar o conhecimento dos processos e os efeitos do CO2 na matriz ciment?cia. Esse fen?meno ocorre atrav?s de rea??es qu?micas entre o ?cido carb?nico, formado pela rea??o do CO2 com a ?gua, e alguns produtos hidratados do cimento. Em subsuperf?cie, devido ao incremento de temperatura e press?o o meio se torna mais danoso, sendo assim, na ?rea de petr?leo e g?s, principalmente a cimenta??o, tem um grande interesse por esta problem?tica. Frente ao exposto, neste trabalho foram desenvolvidos e publicados tr?s artigos intitulados: [Artigo I] Efeitos do di?xido de carbono no cimento Portland: uma rela??o entre a sedimenta??o est?tica e a carbonata??o, [Artigo II] Carbonata??o em cimento Portland para po?os de petr?leo: influ?ncia do tempo de hidrata??o antes do contato com o CO2 e [Artigo III] Estudo sobre a carbonata??o em uma matriz de cimento Portland classe G em ambientes supercr?tico e saturado. No primeiro estudo foi proposto um modelo para o comportamento da sedimenta??o e da carbonata??o ocorrido em uma pasta inst?vel, onde a sedimenta??o est?tica baseia-se na mec?nica dos fluidos. No segundo estudo foram investigadas tr?s pastas com a mesma formula??o, por?m curadas durante per?odos de tempos de 8 horas, 7 dias e 28 dias antes do contato com o CO2. Os resultados mostraram processos distintos, mas com efeitos similares de carbonata??o ao final. E no ?ltimo estudo as amostras foram expostas ao mesmo tempo em CO2 supercr?tico e saturado. As an?lises mostraram resultados significativamente distintos, onde as amostras expostas ao meio saturado sofreram um ataque 35% superior ?quelas submetidas ao CO2 supercr?tico. Este trabalho apresenta estudos que buscam promover uma maior compreens?o da fenomenologia da a??o do CO2 e ao mesmo tempo dar subs?dios para o desenvolvimento de tecnologias que combatam a carbonata??o. / In this study the phenomenon of Portland cement carbonation is investigated by different approaches, but converging towards the same objective: to deepen the knowledge of the processes and the effects in the cement matrix. The phenomenon occurs through chemical reactions between carbonic acid, formed by the reaction of CO2 with water, and some hydrated products of cement. In subsurface due to the increase of temperature and pressure the medium becomes more damaging, being therefore, in the area of oil and gas, mainly cementing, has a great interest by this problematic. In view of the above, in this study three articles were developed and published entitled: [Article I] Effects of carbon dioxide in Portland cement: a relation between static sedimentation and carbonation, [Article II] Carbonation in oil well Portland cement: Influence of hydration time prior to contact with CO2 and [Article III] Study of carbonation in a class G Portland cement matrix at supercritical and saturated environments. In the first study, a model was proposed for sedimentation and carbonation behavior in an unstable slurry, the static sedimentation based on fluid mechanics. In another study, three slurries of the same formulation were investigated, but were cured for periods of 8 hours, 7 days and 28 days before CO2 contact. The results showed distinct processes, but with similar carbonation effects at the end. In addition, in one last study samples were exposed at the same time in supercritical and saturated CO2. The analyzes showed significantly different results, where the samples exposed to the saturated medium suffered a 35% higher attack. This work presents studies that seek to promote a greater understanding of phenomenology and give subsidies for the development of technologies that combat carbonation.