Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-20T20:04:27Z No. of bitstreams: 1 LuanCarvalhoSantanaDeOliveira_DISSERT.pdf: 2245545 bytes, checksum: 12d2d7b903a4e317e9d386eb57ca0374 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-22T20:17:43Z (GMT) No. of bitstreams: 1 LuanCarvalhoSantanaDeOliveira_DISSERT.pdf: 2245545 bytes, checksum: 12d2d7b903a4e317e9d386eb57ca0374 (MD5) / Made available in DSpace on 2017-03-22T20:17:43Z (GMT). No. of bitstreams: 1 LuanCarvalhoSantanaDeOliveira_DISSERT.pdf: 2245545 bytes, checksum: 12d2d7b903a4e317e9d386eb57ca0374 (MD5) Previous issue date: 2017-01-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A utiliza??o de res?duos industriais est? em evid?ncia na atualidade, principalmente em fun??o da quest?o ambiental. Nos ?ltimos anos in?meros comp?sitos foram obtidos e estudados, com a utiliza??o de res?duos e fibras vegetais, desmistificando o conceito de que um material s? pode ser chamado de comp?sito se a carga for de refor?o. Obteve e estudou-se um comp?sito de matriz de resina poli?ster (ortoft?lica e tereft?lica) e carga de enchimento de raspa de madeira produzida em marcenarias. Foram estudados os processos de obten??o dos comp?sitos e a caracteriza??o de propriedades mec?nicas, t?rmicas e f?sicas nas amostras dos comp?sitos com fra??o m?ssica de 10, 20 e 30%, para tr?s diferentes granulometrias, totalizando seis formula??es para porcentagens. Por?m, foi escolhida a formula??o com 20%, pois com essa porcentagem j? tinha atingido a satura??o da mistura. Os ensaios realizados foram de tra??o, flex?o, t?rmico, absor??o de ?gua, densidade, biodegrada??o, degrada??o ambiental e MEV. Os comp?sitos obtidos, em todas as formula??es estudadas, apresentaram resist?ncia mec?nica inferior a da matriz, por?m n?o inviabilizou sua utiliza??o para aplica??es onde n?o s?o requeridos significativos esfor?os. Em termos de resist?ncia t?rmica o comp?sito proposto foi competitivo com a resina matriz, tendo comportamento um pouco inferior. Como esperado os comp?sitos apresentaram maiores ?ndices de absor??o de ?gua quando comparados ?s matrizes polim?ricas. A densidade aparente dos comp?sitos n?o apresentou varia??o significativa em rela??o ?s matrizes utilizadas. Demonstrou-se, portanto, que os res?duos agregados ? resina t?m a fun??o de carga de enchimento. O comp?sito foi utilizado para a fabrica??o de tampos de bancos, demonstrando-se sua viabilidade de aplica??o na fabrica??o de estruturas apara baixas solicita??es mec?nicas. / The use of industrial waste is nowadays evident, especially in the environmental issue. In recent years, the results have been obtained with the use of waste and vegetable fibers, the dismemberment of the concept of a material can be called composite. A polyester resin composite (orthophthalic and terephthalic) composite and filler of wood produced in woodworking was obtained and studied. The processes of obtaining composites and a characterization of mechanical, thermal and physical properties in composite samples with a more specific fraction of 10, 20 and 30% were studied for three different granulometries, totaling six formulations for percentages. However, a formulation with 20% was chosen, because with that percentage already had a saturation of the mixture. The tests carried out for tensile, flexural, thermal, water absorption, density, biodegradation, environmental degradation and MEV tests. The composites obtained in all the studied formulations had lower mechanical resistance than the matrix, however it did not make it impossible to use them in applications where no significant efforts are required. In terms of thermal resistance or composite proposed to competitive with a resin matrix, having somewhat lower behavior. As expected the composites presented higher water absorption indices when compared to the polymer matrices. The apparent density of the composites does not present significant variation in relation to the used dimensions. It has been demonstrated, therefore, that the residues aggregated to the resin have a filling charge function. The composite was used for the manufacture of seat tops, demonstrating its feasibility of application in the fabrication of structures for low mechanical stresses.

Made available in DSpace on 2016-04-28T20:16:30Z (GMT). No. of bitstreams: 1 2009 - Clarissa Pimentel de Souza.pdf: 1413726 bytes, checksum: ad7e79be3b961bab7286264dea8d79c1 (MD5) Previous issue date: 2009-04-29 / The mite Demodex canis is a resident of the hair follicles and when overgrowth cause an inflammatory parasitic disease called demodectic mange. The diagnosis is based on the visualization of the mite under microscope, especially by skin scrapings, hair plucks or histopathologic exam. A large number of drugs has been used on the treatment of demodectic mange, demonstrating varied efficacy numbers, side effects that can prohibit the conclusion of treatment and difficulties to owners. The objective of the present study was to evaluate the efficacy of the fluazuron 2.5% pour on and ivermectin on different therapeutic protocols on the treatment of canine demodectic mange. For this, 31 dogs were divided into five groups, the first four with six animals and the last one with seven. All with positive skin scrapings. The dogs were treated on each 14 days, during 84 days. The first group used fluazuron 2.5% pour on at 20mg/kg, the second used this same drug associated to ivermectin 0.5% pour on at 0.6mg/kg and, the third one, only the ivermectin 0,5% pour on. The fourth and fifth groups were treated with long-acting ivermectin 3.15% on subcutaneous administration at 0.6 and 1.5mg/kg, respectively. The evaluation and follow up of treatments were realized through skin scrapings on each 14 days, clinical evaluation with photos of dogs on every visit for a compare of the lesions. And the histopathologic exam at the end of the therapeutic protocol. The success rate was defined as the percentage of dogs on each group with negative skin scrapings. The reduction in mite numbers reached the efficacy levels of 67.66; 88.99; 84.29; 84.90 and 87.86%, for groups 1, 2, 3, 4 e 5, respectively. And the success rates at the end of treatment were 16.67% for the first group and 50% for the other four. By Wilcoxon test the reduction of the infestation on the histopathologic exam, before and after treatment, had no significance for all groups. Remission of lesions did not occur with the dogs of the first group. On groups 2 and 3, on each one was observed two dogs clinically cured and one with an improvement of the lesions. And on groups 4 and 5, 4 and 5 dogs were cured, respectively and also, there was one with an improvement on the lesions. The fluazuron 2.5% pour on did not show efficacy on the treatment of canine demodectic mange. But the ivermectin 0.5% pour on associated or not to fluazuron 2.5% pour on and the ivermectin 3.15% on both dosages, showed good efficacy on the reduction in mite numbers at the end of the protocols. / O ?caro Demodex canis ? um habitante dos fol?culos pilosos, que quando se prolifera causa uma dermatopatia de cunho inflamat?rio denominada sarna demod?cica. O diagn?stico ? feito atrav?s da visualiza??o do parasito sob microscopia ?ptica, especialmente atrav?s do exame parasitol?gico de raspado cut?neo, dos p?los, ou exame histopatol?gico. Muitas drogas t?m sido utilizadas no tratamento da sarna demod?cica, mas demonstrando n?veis de efic?cia variados, ocorr?ncia de efeitos colaterais que impossibilitam a conclus?o da terapia ou empecilhos ? ades?o dos propriet?rios. O objetivo do presente estudo foi avaliar a efic?cia do fluazuron e da ivermectina em diferentes protocolos terap?uticos no controle da sarna demod?cica canina. Foram avaliados 31 c?es divididos em cinco grupos, os quatro primeiros com seis animais e o ?ltimo com sete, positivos para o ?caro D. canis atrav?s do raspado cut?neo. Todos os c?es foram tratados a cada 14 dias, durante 84 dias. No primeiro grupo foi utilizado fluazuron 2,5% pour on na dosagem de 20mg/kg, no segundo este f?rmaco tamb?m foi empregado, mas associado a ivermectina 0,5% pour on na dosagem de 0,6mg/kg e no terceiro, somente a ivermectina 0,5% pour on . Os c?es do quarto e quinto grupos foram tratados com ivermectina 3,15% longa a??o por via subcut?nea nas dosagens de 0,6 e 1,5mg/kg, respectivamente. A avalia??o e acompanhamento do tratamento foram feitos atrav?s dos exames parasitol?gicos de raspado cut?neo a cada 14 dias, da avalia??o cl?nica, inclusive fotografando os c?es para uma melhor compara??o dos quadros lesionais e, do exame histopatol?gico ao final de cada protocolo terap?utico. A taxa de sucesso foi definida pela porcentagem de c?es em cada grupo que apresentaram raspados negativos. A redu??o na contagem no n?mero de ?caros alcan?ou n?veis de efic?cia de at? 67,66; 88,99; 84, 29; 84,90 e 87,86%, nos grupos 1, 2, 3, 4 e 5, respectivamente. E as taxas de sucesso ao final do tratamento foram de 16,67% para o grupo 1 e 50% para os outros quatro. Pelo do teste de Wilcoxon a redu??o da infesta??o atrav?s do exame histopatol?gico antes e depois do tratamento n?o foi significativa para nenhum grupo. Clinicamente, n?o ocorreu remiss?o das les?es nos c?es do primeiro grupo. Nos grupos 2 e 3, em cada um se observou 2 c?es considerados curados clinicamente e 1 com melhora. J? nos grupos 4 e 5, evidenciou-se 4 e 5 animais curados, respectivamente e, tamb?m um com n?tida melhora do quadro cl?nico. O fluazuron 2,5% pour on n?o demonstrou efic?cia no tratamento da sarna demod?cica canina. J? a ivermectina 0,5% pour on associada ao fluazuron ou como terapia ?nica e, a ivermectina 3,15% por via subcut?nea nas duas dosagens diferentes, foram eficazes na redu??o do n?mero de ?caros ao final dos protocolos terap?uticos.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-10-11T22:51:16Z No. of bitstreams: 1 LilianGraceDaSilvaSolon_TESE.pdf: 7051337 bytes, checksum: 79a5b10c1ce003624bdd49bff3af8afd (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-10-18T00:03:19Z (GMT) No. of bitstreams: 1 LilianGraceDaSilvaSolon_TESE.pdf: 7051337 bytes, checksum: 79a5b10c1ce003624bdd49bff3af8afd (MD5) / Made available in DSpace on 2016-10-18T00:03:19Z (GMT). No. of bitstreams: 1 LilianGraceDaSilvaSolon_TESE.pdf: 7051337 bytes, checksum: 79a5b10c1ce003624bdd49bff3af8afd (MD5) Previous issue date: 2016-02-04 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A ind?stria farmac?utica e laborat?rios anal?ticos de todo o mundo tem focado na qualidade, seguran?a e efic?cia de seus produtos. Processos utilizados para minimizar os riscos, como o Quality by Design (QbD), recentemente tem sido atribu?do ao desenvolvimento de m?todos anal?ticos, principalmente os m?todos cromatogr?ficos. O Analytical Quality by Design ou Qualidade Anal?tica Baseada no Projeto (aQbD), utiliza ferramentas de planejamento de experimentos, an?lise de risco e monitoramento cont?nuo. Para isso, faz-se uso de softwares simuladores, ferramentas estat?sticas e quimiom?tricas. Sabe-se que os m?todos cromatogr?ficos de an?lise s?o bastante consolidados e exigidos pelas ag?ncias regulat?rias, aplicando-se em diversas determina??es dentro do campo farmac?utico, como identifica??o e quantifica??o de f?rmacos, metab?litos, impurezas e produtos de degrada??o. O presente estudo teve como objetivo, utilizar ferramentas aQbD para o desenvolvimento de m?todos em cromatografia l?quida de ultra efici?ncia. Foram desenvolvidos quatro m?todos, a saber: quantifica??o simult?nea de dexametasona acetato e clotrimazol em formas farmac?uticas semiss?lidas, atrav?s de transfer?ncia de m?todo de CLAE para CLUE (cap?tulo 1); determina??o simult?nea de corticosteroides e conservantes em coluna de n?cleo s?lido com tamanho de part?cula 1.3 ?m utilizando software simulador (cap?tulo 2); quantifica??o de betametasona valerato em amostras de creme, gel, lo??o e pomada ap?s desenvolvimento de m?todo por planejamento fatorial completo 33 (cap?tulo 3); e determina??o simult?nea de corticosteroides ap?s desenvolvimento de modelo de previs?o de fator de reten??o por QSRR (cap?tulo 4). Os resultados mostraram que apesar da necessidade de otimiza??o pelo analista, o uso de ferramentas aQbD, como o planejamento estat?stico ou uso de softwares, s?o promissoras no desenvolvimento de m?todos cromatogr?ficos de ultra efici?ncia, uma vez que foram capazes de promover economia de tempo, diminuir os gastos e riscos. Os ensaios apresentaram resultados satisfat?rios em termos de velocidade anal?tica e diminui??o no consumo de solventes. / The pharmaceutical industry and analytical laboratories around the world have focused on quality, safety and efficacy of their products. Processes used to minimize risks, such as Quality by Design (QbD), which recently has been attributed to the development of analytical methods, especially chromatographic methods. The Analytical Quality by Design (aQbD) uses planning tools experiments, risk analysis and continuous monitoring. For this, it makes use of simulation software, statistical tools and chemometrics. It is known that chromatographic methods are well consolidated and required by the regulatory agencies. It has been applied in various determinations in the pharmaceutical field, such as identification and quantification of drugs, metabolites, degradation products and impurities. The aim of this study was to use aQbD tools for the development of methods for ultra high performance liquid chromatography (UHPLC). Four methods were developed, namely: simultaneous quantification of dexamethasone acetate and clotrimazole in semisolid dosage forms, via HPLC to UHPLC method transfer (Chapter 1); simultaneous determination of corticosteroids and preservatives in solid core column with particle size of 1.3 ?m by using simulation software (Chapter 2); betamethasone valerate quantification in samples of cream, gel, lotion and ointment after method development by full factorial design 33 (Chapter 3); and simultaneous determination of corticosteroids after retention factor prediction model by QSRR (Chapter 4). The results showed that despite the need for optimization by the analyst, the use of aQbD tools such as statistical design or use of software, the aQbD is promising in the development of chromatographic methods of ultra efficiency, since they were able to promote time savings, lower costs and risks. The tests showed satisfactory results in terms of analysis speed and decrease of solvent consumption.

Made available in DSpace on 2014-12-17T14:58:16Z (GMT). No. of bitstreams: 1 FlanelsonMM_DISSERT.pdf: 1939594 bytes, checksum: c1934fd33d598afaeecd6db2f0256219 (MD5) Previous issue date: 2012-10-01 / In recent decades, ceramic products have become indispensable to the technological development of humanity, occupying important positions in scientific production and consequently in industrial production. One area of the economy that continues to absorb large amounts of the products of this sector is Construction. Among the branches of the ceramic industry, there are the red ceramic industry which is traditionally the basis of that economic sector. Among the reasons for which the red ceramic industry became popular in the country, and specifically in Rio Grande do Norte, is the abundance of this raw material, easily found throughout the national territory. However, it appears that the red ceramic industry has deficiencies in technology and skilled labor, resulting in the production of ceramic goods with low added value. Among the factors that determine the quality of the ceramic products red has the proper formulation of the ceramic mass, the conformation and the firing temperature. Thus, the overall goal of this work is to study the mineralogical and technological properties, two clays from the region of the Wasteland Potiguar industrial ceramist. Therefore, the raw materials were characterized by analysis of Xray diffraction (XRD) analysis, X-ray fluorescence (XRF), particle size analysis (FA), scanning electron microscopy (SEM), optical microscopy (OM ), plasticity index (PI), thermal gravimetric analysis (TGA) and differential thermal analysis (DTA). The technological properties of the material were analyzed by water absorption tests (AA%) porosity (% PA), the linear shrinkage (RT%), apparent density (MEA), loss on ignition (PF%) and flexural strength three points (TRF) / Nas ?ltimas d?cadas, os produtos cer?micos se tornaram indispens?veis para o desenvolvimento tecnol?gico da humanidade, ocupando posi??es importantes na produ??o cient?fica e consequentemente na produ??o industrial. Uma das ?reas da economia que continua absorvendo grandes quantidades dos produtos desse setor ? a Constru??o Civil. Entre os ramos do setor ceramista, destacam-se as ind?strias de cer?mica vermelha que ? tradicionalmente a base desse segmento econ?mico. Entre os motivos pelo quais as ind?strias de cer?micas vermelhas se popularizaram no pa?s, e especificamente no Rio Grande do Norte, ? a abund?ncia dessa mat?ria prima, encontrada com facilidade por todo territ?rio nacional. Entretanto, constata-se que a ind?stria de cer?mica vermelha possui defici?ncias em tecnologia e m?o de obra qualificada, resultando na produ??o de pe?as cer?micas com baixo valor agregado. Entre os fatores que determinam a qualidade dos produtos da cer?mica vermelha, tem-se a formula??o adequada da massa cer?mica, a conforma??o e a temperatura de queima. Sendo assim, o objetivo geral desse trabalho ? estudar as propriedades mineral?gicas e tecnol?gicas, de duas argilas provenientes da regi?o do Agreste Potiguar para a ind?stria ceramista. Para tanto, as mat?rias primas foram caracterizadas atrav?s das an?lises de difratometria de Raios-X (DRX), an?lise de fluoresc?ncia de Raios-X (FRX), an?lise granulom?trica (AG), microscopia eletr?nica de varredura (MEV), microscopia ?ptica (MO), ?ndice de plasticidade (IP), an?lise termogravim?trica (ATG) e an?lise t?rmica diferencial (ATD). As propriedades tecnol?gicas do material foram analisadas pelos ensaios de absor??o de ?gua (AA%), porosidade aparente (PA%), retra??o linear (RT%), massa espec?fica aparente (MEA), perda ao fogo (PF%) e resist?ncia a flex?o em tr?s pontos (TRF)

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-12T15:47:41Z No. of bitstreams: 1 JanainaDaSilvaGoes_DISSERT.pdf: 2421802 bytes, checksum: 8409f2ebc5498e05da2a012cbbab5963 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-20T14:38:17Z (GMT) No. of bitstreams: 1 JanainaDaSilvaGoes_DISSERT.pdf: 2421802 bytes, checksum: 8409f2ebc5498e05da2a012cbbab5963 (MD5) / Made available in DSpace on 2017-01-20T14:38:17Z (GMT). No. of bitstreams: 1 JanainaDaSilvaGoes_DISSERT.pdf: 2421802 bytes, checksum: 8409f2ebc5498e05da2a012cbbab5963 (MD5) Previous issue date: 2013-08-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Atualmente, os medicamentos utilizados em crian?as s?o adaptados a partir de formas farmac?uticas s?lidas desenvolvidas para adultos. O captopril ? amplamente adaptado para formula??o l?quida em hospitais. Sua estabilidade em meio aquoso ? reduzida, pois sofre oxida??o gerando o dissulfeto de captopril. Com o intuito de garantir a estabilidade do f?rmaco e dosagem precisa, foi desenvolvido um estudo de pr?-formula??o para a obten??o de uma formula??o de captopril em p? para constitui??o de uma solu??o est?vel de uso pedi?trico. A compatibilidade entre o f?rmaco e os poss?veis excipientes foi avaliada atrav?s das an?lises de calorimetria de varredura diferencial (DSC) e o comportamento t?rmico do captopril atrav?s das an?lises termogravim?tica (TG) e t?rmica diferencial (DTA). Em seguida, foram realizados os ensaios de an?lise granulom?trica e das medidas indiretas de fluxo do captopril e dos excipientes. Para estudo em solu??o, foram obtidas diferentes formula??es a partir de planejamento fatorial, em que se variou a concentra??o de EDTA (0,005 e 0,1%) e pH (2,5; 4,0 e 5,5) em ?gua destilada e ?gua mineral, que foram armazenadas a 60?C e analisadas ao longo de doze dias por CLAE para avalia??o da estabilidade do captopril. Nas curvas DSC das misturas de captotpril com os conservantes, a sucralose e o ?cido c?trico, os eventos t?rmicos de cada subst?ncia isolada n?o foram mantidos. Nas demais curvas das misturas bin?rias os eventos correspondentes a cada componente foram preservados, indicando compatibilidade entre as subst?ncias. Foi observada uma grande diferen?a na distribui??o e di?metro m?dio das part?culas e densidade dos agentes tamponantes em compara??o ?s demais subst?ncias, o que pode ocasionar a segrega??o da mistura de p?s. A partir do estudo da estabilidade das solu??es, foi verificado que as vari?veis interferem significativamente (p = 0,05) no teor do captopril, sendo o pH o fator mais relevante. As intera??es entre as vari?veis foram significativas, com maior estabilidade observada em pH pr?ximo a 4,0, maior concentra??o de EDTA e uso de ?gua mineral. Com base nos resultados, pode-se concluir que o desenvolvimento de uma formula??o de captopril est?vel ? vi?vel desde que sejam adotadas medidas estrat?gicas a fim de se evitar a segrega??o dos p?s constituintes da formula??o. / Nowadays, drugs used in children are adapted from solid dosage forms developed for adults. Captopril in solid dosage form is widely adapted in hospitals into a liquid formulation. Its stability in aqueous solutions is reduced because it undergoes oxidation, forming captopril disulfide. In order to ensure a stable and accurate dosage form, a pre-formulation study was developed for obtaining a stable formulation of a powder for preparation of a captopril solution for pediatric use. The compatibility between drug and possible excipients were evaluated by differential scanning calorimetry (DSC) and the captopril thermic behavior, through thermogravimetric analysis (TG) and differential thermal analysis (DTA). Then, particle size and indirect flow measures of captopril and excipients were analyzed. For solution studies, different formulations were obtained through factorial design, varying the EDTA concentration (0.005 and 0.1%) and pH (2.5, 4.0 e 5.5) in distilled and mineral water, which were stored at 60?C and analyzed over twelve days by HPLC to evaluate the stability of captopril. In the DSC curves of captopril mixtures with preservatives, sucralose and citric acid, the isolated thermal events were not maintained. In the other binary mixtures, the events corresponding to each component were preserved in the curves, indicating compatibility between substances. There was a major difference in the distribution and average particles diameters and density of buffering agents in comparison to other substances, which can cause segregation of the powder mixture. From the study of the solutions stability it was found that the variables interfere significantly (p = 0.05) in the captopril content, the pH being the most important factor. The interactions between variables were significant, with greater stability around pH 4.0, higher EDTA concentrations and use of mineral water. Based on the results, it can be concluded that development of a stable captopril formulation is viable if strategic measures are adopted in order to avoid segregation of the powders constituents of the formulation.

Made available in DSpace on 2014-12-17T14:07:23Z (GMT). No. of bitstreams: 1 RoseMPRM.pdf: 2750007 bytes, checksum: ceb71a52be1f10c01d507218438ebc24 (MD5) Previous issue date: 2007-05-02 / Rio Grande do Norte State stands out as one great producer of structural clay of the brazilian northeastern. The Valley Assu ceramic tiles production stands out obtained from ilitics ball clays that abound in the region under study. Ceramics formulation and the design of experiments with mixture approach, has been applied for researchers, come as an important aid to decrease the number of experiments necessary to the optimization. In this context, the objective of this work is to evaluate the effects of the formulation, temperature and heating rate in the physical-mechanical properties of the red ceramic body used for roofing tile fabrication of the Valley Assu, using design of mixture experiments. Four clays samples used in two ceramics industry of the region were use as raw material and characterized by X-ray diffraction, chemical composition, differential thermal analysis (DTA), thermogravimetric analysis (TGA), particle size distribution analysis and plasticity techniques. Afterwards, they were defined initial molded bodies and made specimens were then prepared by uniaxial pressing at 25 MPa before firing at 850, 950 and 1050 ?C in a laboratory furnace, with heating rate in the proportions of 5, 10 e 15 ?C/min. The following tecnologicals properties were evaluated: linear firing shrinkage, water absorption and flexural strength. Results show that the temperature 1050 ?C and heating rate of 5 ?C/min was the best condition, therefore presented significance in all physical-mechanical properties. The model was accepted as valid based of the production of three new formulations with fractions mass diferents of the initial molded bodies and heated with temperature at 1050 ?C and heating rate of 5 ?C/min. Considering the formulation, temperature and heating rate as variables of the equations, another model was suggested, where from the aplication of design of experiments with mixtures was possible to get a best formulation, whose experimental error is the minor in relation to the too much formulations / O Estado do Rio Grande do Norte ? um dos principais produtores de cer?mica vermelha do nordeste brasileiro. A regi?o do Vale do Assu destaca-se na produ??o de telhas cer?micas, cuja principal constitui??o s?o argilas pl?sticas il?ticas, abundantes na regi?o. O estudo das formula??es de massas cer?micas, juntamente com o aux?lio do planejamento experimental para misturas, tem sido utilizado por pesquisadores, visando a diminui??o do n?mero de experimentos necess?rios para a otimiza??o de formula??es. Neste contexto, este trabalho tem por objetivo estudar o efeito das formula??es, temperatura e taxa de queima nas propriedades f?sico-mec?nicas das massas cer?micas para fabrica??o de telhas da regi?o do Vale do Assu, utilizando planejamento de experimentos para misturas. Quatro argilas usadas em duas ind?strias cer?micas da regi?o foram utilizadas como mat?ria-prima e submetidas a ensaios de difra??o de raio X, composi??o qu?mica, TG/DTA, distribui??o de tamanho de part?cula e plasticidade. Foram definidas formula??es iniciais e confeccionados corpos-de-prova por prensagem uniaxial e de simples efeito a 25 MPa e queimados a 850, 950 e 1050 ?C, com taxas de aquecimento de 5, 10 e 15 ?C/min. As propriedades tecnol?gicas de queima avaliadas foram retra??o linear, absor??o de ?gua e resist?ncia ? flex?o (tr?s pontos). Resultados mostram que a temperatura 1050 ?C e taxa de aquecimento de 5 ?C/min foi a melhor condi??o de queima, pois apresentou efeito de signific?ncia em todas as propriedades f?sico-mec?ncias. O modelo foi validado a partir da produ??o de tr?s novas formula??es com fra??es m?ssicas diferentes das formula??es iniciais e queimadas com temperatura a 1050 ?C e taxa de queima de 5 ?C/min. Considerando as formula??es, temperaturas e taxas de aquecimento como vari?veis das equa??es, outro modelo foi sugerido, onde a partir da aplica??o do planejamento de experimentos para misturas foi poss?vel obter uma formula??o ?tima, cujo erro experimental ? o menor em rela??o ?s demais formula??es

Made available in DSpace on 2014-12-17T14:57:50Z (GMT). No. of bitstreams: 1 FelipeLFA.pdf: 4959653 bytes, checksum: 0da7f126d56ee6a849bfaf9a5d53da1d (MD5) Previous issue date: 2009-03-06 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / This work has for objective study compared the characteristics and technological properties of ceramic bodies from the region of Serid?-RN. The region under study has identified 23 cities where they were 80 ceramics industries. To define the universe of search, there was a survey of pottery that are part of APL Serid? next to the IEL. The characteristics and operating conditions of ceramics industries of the region were identified through a socio-economic questionnaire applied locally, which addressed issues such as: profiles of companies, production process etc. The analysis of information collected from 24 companies identified in seven cities shows that the vast majority of industries is small, with family structure, obsolete equipment and labo, little qualified. Most of the pottery works with low technical knowledge, poor control of the production process and product technology. The raw collected were submitted to analysis of X ray diffraction, chemical composition, termical analysis, particle size distribution and plasticity. Then were produced five formulations and made by uniaxial pressure at 25 MPa for firing in temperatures varying from 850 to 1050 ?C. The firing technological properties evaluated were: mass loss to fire, lineal shrinkage, apparent density, apparent porosity, water absorption and flexural strength (3 points). The results indicated that the raw materials from the region have significant similarities in the composition chemical and mineralogical. Furthermore, it indicates the possibility of the use of cycles of firing faster and efficient than the current, limited to some clay mass burning of certain conditions / Este trabalho teve como objetivo estudar comparativamente as caracter?sticas e propriedades tecnol?gicas de massas cer?micas para telhas da regi?o do Serid?-RN. A Regi?o em estudo possui 23 munic?pios onde foram identificadas 80 ind?strias cer?micas. Para defini??o do universo da pesquisa, fez-se um levantamento das olarias que fazem parte da APL Serid? junto ao IEL do Estado. As caracter?sticas e condi??es de funcionamento das ind?strias cer?micas da regi?o foram identificadas atrav?s de um question?rio s?cio-econ?mico aplicado in loco, que abordava aspectos como: perfil das empresas, processo produtivo etc. A an?lise das informa??es coletadas em 23 empresas identificadas em sete munic?pios permite concluir que a grande maioria das ind?strias ? de pequeno porte, com estrutura familiar, equipamentos obsoletos e m?o-de-obra pouco qualificada. Grande parte das olarias opera com baixo conhecimento t?cnico, prec?rios controles do processo produtivo e tecnol?gico dos produtos. As mat?rias-primas coletadas foram submetidas a ensaios de difra??o de raios X, composi??o qu?mica, an?lise t?rmica, distribui??o de tamanho de part?culas e plasticidade. Em seguida foram produzidas cinco formula??es e confeccionados corpos-de-prova por prensagem uniaxial a 25 MPa para queima variando de 850 ?C a 1050?C. As propriedades tecnol?gicas de queima avaliadas foram: perda de massa ao fogo, retra??o linear, massa espec?fica aparente, porosidade aparente, absor??o de ?gua e carga de ruptura ? flex?o (3 pontos). Os resultados indicaram que as mat?rias-primas provenientes da regi?o apresentam significativas semelhan?as quanto ? composi??o qu?mica e mineral?gica. Al?m disso, indica-se a possibilidade da utiliza??o de ciclos de queima mais r?pidos e eficientes que os atuais, limitando algumas massas argilosas para certas condi??es de queima

Made available in DSpace on 2014-12-17T14:06:58Z (GMT). No. of bitstreams: 1 JaqueligiaBS_Capa_ate_referencias.pdf: 4148676 bytes, checksum: c08764d974461ebcf86494a06a296078 (MD5) Previous issue date: 2008-10-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In building, during the implementation process of major or even minor works, there is a considerable waste of plaster in the steps of coating, making it is a negative factor because of the loss of these processes constructive remains incorporated into buildings, as component, whose final dimensions are higher than those projected. Another negative factor is the disposal of waste gypsum in inappropriate places, thus contributing to the degradation of environmental quality, due to the leaching of this waste and may trigger the formation of sulfuric acid. Therefore, based on this picture, processing and reuse of waste coating, combined with the ceramics industry, which is a strong potential in the reuse of certain types of waste, promote mutual benefits. Thus the overall objective of this work is to conduct a search with scientific and technological aspects, to determine the effect of the incorporation of the residue of plaster for coating, from the building, the formulation of bodies for red ceramic. The residue of plaster coating was collected and characterized. They were also selected raw materials of two ceramic poles of the state of Rio Grande do Norte and formulations have been made with the intention of obtaining those with the best physical and mechanical properties, the residue was added the percentage of 5%, 10%, 15%, 20%, 25% and 30%, in the best formulation of ceramic industry 1 and, according the properties analyses, 5%, 10% and 15% as the best results of ceramic industry 2. The samples were sintered at temperatures of 850 ?C, 950 ?C and 1050 ?C, the heating rate of 5 ?C / min with isotherm of two hours. They were submitted to testing technology, such as lineal shrinkage, water absorption, apparent porosity, apparent density and bending resistence. The residue incorporation best results in the formulations of mass in red ceramic, were observed between the temperatures of 850 ?C and 950 ?C, in those formulations that have illite clays and medium plastic in their composition, in the range of 0% to 15% residue incorporated / Na constru??o civil, durante o processo de execu??o de grandes ou at? mesmo pequenas obras, h? um desperd?cio consider?vel de gesso nas etapas de revestimento, tornando-se este um fator negativo, pois parte das perdas destes processos construtivos permanece incorporada nas constru??es, na forma de componentes, cujas dimens?es finais s?o superiores ?quelas projetadas. Outro fator negativo ? a disposi??o dos res?duos de gesso em locais inadequados, contribuindo assim para a degrada??o da qualidade ambiental, devido ao processo de lixivia??o deste res?duo, podendo desencadear na forma??o de ?cido sulf?rico. Baseado neste panorama, a transforma??o e o reaproveitamento dos res?duos de revestimento, aliada ? ind?stria da cer?mica, que ? um forte potencial no reaproveitamento de alguns tipos de res?duos, promoveria benef?cios m?tuos. O objetivo geral deste trabalho foi de realizar uma pesquisa com aspectos cient?ficos e tecnol?gicos, para verificar o efeito da incorpora??o do res?duo de gesso para revestimento, proveniente da constru??o civil, na formula??o de massas para cer?mica vermelha. As mat?rias-primas foram coletadas de dois p?los cer?micos do Estado do Rio Grande do Norte e formuladas com o intuito de obter aquelas com as melhores propriedades f?sicas e mec?nica, tendo sido incorporados os percentuais 5%, 10%, 15%, 20%, 25% e 30% de res?duo, na melhor formula??o da ind?stria cer?mica 1 e, de acordo com a an?lise dos seus resultados, de 5%, 10% e 15% na melhor formula??o da ind?stria cer?mica 2. As amostras foram sinterizadas ?s temperaturas de 850 ?C, 950 ?C e 1050 ?C, ? taxa de aquecimento de 5 ?C/min com isoterma de duas horas e submetidas a ensaios tecnol?gicos, como retra??o linear de queima, absor??o de ?gua, porosidade aparente, massa espec?fica aparente e resist?ncia mec?nica ? flex?o. Os melhores resultados de incorpora??o do res?duo nas formula??es de massa de cer?mica vermelha foram observados na faixa de temperatura de 850 ?C a 950 ?C, naquelas que possuem argilas il?ticas e medianamente pl?sticas em sua composi??o, na faixa de 0% a 15% de res?duo incorporado