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Adi??o de cascalho de perfura??o da bacia potiguar em argilas para uso em materiais cer?micos: influ?ncia da concentra??o e temperatura de queima.Medeiros, Leonardo Coutinho de 22 April 2010 (has links)
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Previous issue date: 2010-04-22 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / One of waste produced on large scale during the well drilling is the gravel drilling. There are techniques for the treatment of the same, but there isn t consensus on what are the best in
terms of economic and environmental. One alternative for disposal of this waste and objective of this paper is the incorporation and immobilization of gravel clay matrix to
assess their technological properties. The Raw Materials used were characterized by the following techniques: Chemical Analysis by X-ray fluorescence (XRF), mineralogical analysis by X-ray Diffraction (XRD), Grain Size Analysis (FA) and Thermal Analysis by Thermogravimetry (TG) and thermodiferential (DTA). After characterizing, samples were formulated in the following percentages: 0, 5, 10, 15, 25, 50, 75, 100% (weight) of gravel
drilling, then the pieces were pressed, dried (110 ? C) and sintered at temperatures of 850, 950 and 1050 ? C. After sintering, samples were tested for water absorption, linear
shrinkage, flexural strength, porosity, density, XRD and test color. The results concluded that the incorporation of gravel drilling is a viable possibility for solid masonry bricks and
ceramic blocks manufacture at concentrations and firing temperature described here. Residue incorporation reduces an environmental problem, the cost of raw materials for manufacture of ceramic products / Um dos res?duos produzidos em grande escala durante a perfura??o de po?os de petr?leo ? o cascalho de perfura??o. Existem t?cnicas para seu tratamento, mas n?o existe um consenso sobre quais s?o as melhores do ponto de vista econ?mico e ambiental. Uma das alternativas de destina??o final deste res?duo e objetivo de estudo deste trabalho ? a incorpora??o e imobiliza??o do cascalho em matrizes argilosas para avaliar as suas propriedades tecnol?gicas. As Mat?rias-Primas utilizadas foram caracterizadas pelas seguintes t?cnicas:
An?lise Qu?mica por Fluoresc?ncia de raios-X (FRX); An?lise Mineral?gica por Difra??o de raios-X (DRX); An?lise Granulom?trica (AG) e An?lise T?rmica por Termogravimetria
(TG) e Termodiferencial (DTA). Ap?s a caracteriza??o, as amostras foram formuladas nas seguintes porcentagens: 0, 5, 10, 15, 25, 50, 75, 100% em peso de cascalho de perfura??o,
em seguida as pe?as foram prensadas, secas (110 ?C) e sinterizadas nas temperaturas de 850, 950 e 1050 ?C. Ap?s a sinteriza??o, as amostras foram submetidas a ensaios de Absor??o de ?gua, Retra??o Linear de Queima, Tens?o de Ruptura ? Flex?o, Porosidade Aparente, Massa Espec?fica Aparente, DRX e Ensaio de Cor. Os resultados obtidos conclu?ram que a incorpora??o de cascalho de perfura??o ? uma possibilidade vi?vel para a fabrica??o de tijolos maci?os de alvenaria e blocos cer?micos em determinadas concentra??es e
temperaturas de queima descrita neste trabalho. A incorpora??o deste res?duo al?m de amenizar um problema ambiental, reduz os custos com mat?rias-primas para fabrica??o de produtos cer?micos
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Avalia??o n?o destrutiva da qualidade da madeira e do fuste de ?rvores de Peltophorum dubium (Spreng.) Taub em ?rea de restaura??o florestal / Nondestructive evaluation of wood quality of the trunk of Peltophorum dubium (Spreng.) Taub in forest restoration areaXavier, Carolina Nogueira 26 February 2016 (has links)
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Previous issue date: 2016-02-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This researh aimed to evaluate the quality of the wood of Peltophorum dubium (canaf?stula), obtained in forest restoration areas using non-destructive methods. The 18 individuals of canafistula studied are located in three different locations in the farm Santana do Monte Alegre, Descalvado/SP and were evaluated at 14 years of age. The following non-destructive methods for evaluating the quality of the wood in trees alive were used: densitometry X-ray - which analyzed the radial variation of wood density in micron levels; resistograph - for the assessment of the density of the tree and plant still in the field; and extensometer, used to verify the longitudinal residual strain (LRS). For the silvicultural analysis of the species was measured the CBH (circumference at breast height) and calculated the annual periodic increment in diameter. For qualitative analysis of the trunk, were observed and recorded the following characteristics: presence of fork, hollow timber and tortuosity of the trunk. It was also performed chemical analysis of soil in three different locations. It was found that the radial variation in density has increased in canaf?stula on pith to bark, showing the moderately high density of canaf?stula. The trees hasn?t the presence of internal hollow. The results of longitudinal residual strain showed that the species approached values found in Eucalyptus clones and showed significant and positive correlations with the DBH and the average annual diameter increment. The canasfistula trees showed good quality of the stem in 77,8% of subjects and regular in 22,2% of them, with capacity to produce straight stems with few bifurcations. In the three locations there was a statistical difference in relation to DBH and annual periodic increment in diameter, a fact related to the data of chemical analysis of soil. The site number 3 showed the largest DBH and increment in diameter, it has higher levels of calcium and magnesium, elements that are limiting to the growth of canaf?stula. A non-destructive methodology proved to be a fast tool field use and low cost, compared to traditional destructive methods. Therefore, the timber of canafistula among the studied technological properties, showed good quality for use in the lumber industry also presenting silvicultural characteristics which favor the use of the species for the timber, such as the development of upright stems and few forked, results that contribute to higher yields in the processing in lumber. Considering together all the features and properties studied, the species showed a great potential for the production and insertion in the timber sector / O presente estudo teve como objetivo avaliar a qualidade da madeira das ?rvores de Peltophorum dubium (canaf?stula) obtida em ?rea de restaura??o florestal utilizando m?todos n?o destrutivos. Os 18 indiv?duos de canaf?stula estudados est?o localizados em tr?s diferentes s?tios na Fazenda Santana de Monte Alegre, Descalvado/SP, e foram avaliados aos 14 anos de idade. As seguintes metodologias n?o destrutivas foram utilizadas para avaliar a qualidade da madeira em ?rvores vivas: densitometria de raios X - que analisou a varia??o radial da densidade da madeira em n?veis microm?tricos; resistografia - para a avalia??o da densidade e fitossanidade da ?rvore ainda no campo; e extensometria, para avaliar a deforma??o residual longitudinal (DRL). Para a an?lise silvicultural da esp?cie foi mensurado o CAP (circunfer?ncia a altura do peito) e calculado o incremento diam?trico. Para a an?lise qualitativa do fuste, foram observadas e anotadas as seguintes caracter?sticas: presen?a de bifurca??o, ocos e tortuosidade do fuste. Foi ainda realizada a an?lise qu?mica do solo nos tr?s diferentes s?tios. Verificou-se que a varia??o radial da densidade da canaf?stula possui um aumento no sentido medula-casca, sendo a densidade da canaf?stula moderadamente alta. Em rela??o a fitossanidade nenhuma ?rvore apresentou ocos internos. Os resultados da deforma??o residual longitudinal mostraram que a esp?cie aproximou-se de valores encontrados em clones de Eucalyptus e apresentou correla??es significativas e positivas com o DAP e o incremento diam?trico m?dio anual. As ?rvores de canaf?stula apresentaram boa qualidade do fuste em 77,8% dos indiv?duos e regular em 22,2% deles, apresentando capacidade de produzir fustes retos e com poucas bifurca??es. Nos tr?s s?tios observou-se diferen?a estat?stica em rela??o ao DAP e ao incremento diam?trico, fato relacionado aos dados da an?lise qu?mica do solo. O s?tio 3 foi o que apresentou maiores DAP e incremento diam?trico, este possui maiores n?veis de Ca e Mg, elementos que s?o limitantes para o crescimento da canaf?stula. A metodologia n?o destrutiva mostrou-se uma ferramenta de r?pida utiliza??o no campo e de baixo custo, comparada ?s metodologias destrutivas tradicionais. Portanto, a madeira de canaf?stula, dentre as propriedades tecnol?gicas estudadas, demonstrou boa qualidade para o uso no setor madeireiro, apresentando tamb?m caracter?sticas silviculturais que propiciam o uso da esp?cie para a produ??o de madeira, como por exemplo, o desenvolvimento de fustes retos e poucos bifurcados, resultados que contribuem para maiores rendimentos na transforma??o em madeira serrada. Considerando em conjunto todas as caracter?sticas e propriedades estudadas, a esp?cie apresentou um ?timo potencial para a produ??o e inser??o no setor madeireiro.
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Estudo da adi??o de finos de rocha na fabrica??o de blocos e tijolos de veda??o do extremo sul da BahiaReis, Edmilson Pedreira dos 28 June 2016 (has links)
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Previous issue date: 2016-06-28 / O ?p? de pedra? ? um res?duo resultante do beneficiamento de rochas para
obten??o de britas utilizadas na constru??o civil, tendo estas o seu uso mais comum
em concretos. A sua gera??o ? na ordem de 10% a 15% do volume total de pedra
beneficiada e, normalmente, s?o depositadas na ?rea da empresa de minera??o. O
objetivo desta pesquisa foi desenvolver blocos e tijolos cer?micos, com mat?riasprimas
provenientes da regi?o de Eun?polis, no extremo sul da Bahia, com adi??o
deste res?duo na argila de queima vermelha. Com isso, pretende-se dar destino
adequado ao res?duo e, ao mesmo tempo, preservar as jazidas de argila da regi?o,
reduzindo o impacto ambiental causado por sua explora??o. As massas cer?micas
foram formuladas com a t?cnica de planejamento de misturas, utilizando, para isso,
o software Statistic. As porcentagens do res?duo na massa foram de 0, 15 e 30%,
em massa, definidas pelo software em fun??o do limite m?ximo de 30% de res?duo
que foi utilizada na massa cer?mica. Foram confeccionados corpos de provas nas
dimens?es de 60x20x5 mm3 em matriz met?lica, e prensados uniaxialmente com
uma press?o de 25 MPa. A queima ocorreu nas temperaturas de 825?C, 925?C e
1025?C, com taxa de aquecimento de 1?C/min, 8?C/min e 15?C/min, e patamar de
180 minutos na temperatura m?xima. A caracteriza??o das mat?rias-primas e das
massas formuladas foi realizada atrav?s de ensaios de granulometria, limites de
Atterberg, fluoresc?ncia de raios X (FRX), difra??o de raios X (DRX), microscopia
eletr?nica de varredura (MEV), microscopia ?tica (MO), an?lise termogravim?trica
(TG) e calorimetria explorat?ria diferencial (DSC). As propriedades f?sicas
determinadas foram a absor??o de ?gua, retra??o linear, porosidade, resist?ncia ?
flex?o e massa espec?fica aparente. Foi analisado, tamb?m, o comportamento da
massa cer?mica, no que diz respeito ? extrus?o dos blocos cer?micos em extrusora
de laborat?rio, determinando a sua resist?ncia ? compress?o (Rc) e absor??o de
?gua (AA). A efic?cia do planejamento de misturas foi confirmada, realizando os
mesmos ensaios mec?nicos e f?sicos em uma nova formula??o feita com percentual
diferente das utilizadas para obten??o do modelo de regress?o, mas ainda, dentro
da regi?o de interesse. A an?lise dos resultados permitiu demonstrar a viabilidade da
incorpora??o do res?duo em at? 30% nas argilas, para fabrica??o de blocos
cer?micos e tijolos maci?os utilizados em alvenaria de veda??o. / Stone dust is a residue resulting from the processing of rocks for obtaining
gravel used in civil construction, most commonly in concrete. It is generated in the
order of 10% to 15% of the total volume of the stone employed and is typically
deposited throughout and around the area of the mining company. The objective of
this study was to develop and ceramic blocks and bricks utilizing raw materials
readily available in region of Eun?polis, extreme south of Bahia, with the addition of
this residue to the red clay. Consequently, it aims to provide a suitable end-use for
the residue, at the same time preserving deposits of clay in the region by reducing
the environmental impact caused by their exploitation. The ceramic masses were
formulated following a mixture-planning technique through the use of the Statistic
software. The total percentages of residue used in the mass were of between 15%
and 30%, as defined by the software on the stipulation of a 30% ceiling on the
residue used in the mass. In a metal matrix, 60x20x5 mm3 test samples were created
and then pressed uni-axially at a pressure of 25 MPa. The firing was performed at
temperatures of 825?C, 925?c and 1025?C, with concordant heating rates of 1?C/min,
8?C/min and 15?C/min and an established time limit of 180 minutes at the maximum
temperature. Characteristics of the raw materials and resultant masses were
measured through testing of granulometry, Atterberg limits, X-ray fluorescence
(XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), optical
microscopy (OM), thermos-gravimetric analysis (TGA) and exploratory differential
scanning calorimetry (DSC). The physical properties measured were determined
water absorption, linear retraction, porosity, resistance to flexion and apparent
specific mass. Additionally, the behavior of ceramic mass in regards to extrusion of
the ceramic blocks using a laboratory extruder was analyzed, determining its
resistance to compression (Rc) and water absorption (AA). Effectiveness of the
mixture formulation was confirmed by performing the same physical and mechanical
testing on a new formulation with different percentages than those used for obtaining
the regression model, though still within the targeted range. Analysis of the results
demonstrated the viability of incorporating the residue in masses, in quantities of up
to 30%, for the manufacture of solid ceramic blocks and bricks used in masonry.
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Desenvolvimento de formula??es para produ??o de gr?s porcelanato a partir de mat?rias-primas da regi?o da bacia do Parna?baLuz, Jota Carlos 04 July 2008 (has links)
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Previous issue date: 2008-07-04 / Brazil is a great ceramic raw materials productor because of the its big number of clay deposits, in various areas of the ceramic industry. Although, the majority of the natural reservations are unknown or not studied yet, so there is no scientific technical dates that can guide their usage and industrial application, as well as the racional and optimazed way of usage by the industrial sector. The state of Maranh?o has a gigant mineral wealth as esmectite, bentonite, kaolin, clays, feldspates, marine salt, iron and others, but produce only products with small agregated value compared to the porcelanato, one of the most expensives ceramic cover tiles, the reason for that is the low water absorption (lower than 0,5%), beside present amazing tecnicals features, like mechanical resistence. The main objective of the work is to do the characterization of four clays, with the finallity of find an application by the results and develop formulations to produce porcelanato using these raw materials from Timon-MA. For this were made the raw materials characterization using X ray fluorecence; X ray diffraction; Differencial thermal analysis; Dilatometric analysis and Tecnological properties, planing three formulations that were sinterized at six different temperatures: 1150, 1170, 1190, 1210, 1230 and 1250?C for 7 minutes. After the sinteratization, the samples were submitted to tension resistance analysis. Were attained two formulations with the requested properties to produce porcelanato / O Brasil ? um grande produtor de mat?rias-primas cer?micas, em virtude do grande n?mero de jazidas de argilas que possui, nas diversas ?reas da ind?stria cer?mica. Todavia, a grande maioria destas reservas naturais ? desconhecida ou permanece indevidamente estudada, n?o havendo assim dados t?cnico-cient?ficos que orientem sua utiliza??o e aplica??o industrial, bem como sua utiliza??o de maneira mais racional e otimizada por parte do setor industrial. O maranh?o possui grandes riquezas minerais como esmectita, bentonita, caulim, argilas, feldspatos, micas, min?rio de ferro, talco, sal marinho, entre outras, no entanto produz apenas produtos de baixo valor agregado em rela??o ao gr?s porcelanato, uma das mais nobres cer?micas de revestimento, devido a sua baixa absor??o de ?gua (tipicamente abaixo de 0,5%), al?m de apresentar excelentes caracter?sticas t?cnicas, destacando-se resist?ncia mec?nica, ao risco e ao manchamento. Assim, o objetivo principal deste trabalho ? caracterizar quatro argilas, com a proposta final de uma aplica??o atrav?s dos resultados obtidos em laborat?rios e desenvolver formula??es para produ??o de gr?s porcelanato a partir de mat?rias-primas da regi?o de Timon-MA. Para isso, foi feita a caracteriza??o das mat?rias-primas por Fluoresc?ncia de Raios X; Difra??o de Raios X; An?lise t?rmica Diferencial; An?lise T?rmica Diferencial, An?lise Dilatom?trica e Propriedades Tecnol?gicas, elaborando tr?s formula??es que foram queimadas em seis temperaturas: 1150, 1170,1190 1210, 1230 e 1250?C com 7 minutos de patamar. Ap?s a queima, os corpos-de-prova foram submetidos a ensaios f?sico-mec?nicos e tamb?m por Microscopia Eletr?nica de Varredura. Foram obtidos para duas formula??es propriedades compat?veis com as exigidas para o gr?s
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Influ?ncia do teor de calc?rio no comportamento f?sico, mec?nico e microestrutural de cer?micas estruturaisSoares, Roberto Arruda Lima 26 March 2008 (has links)
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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
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Estudo de pr?-formula??o para a obten??o de uma formula??o de captopril para uso pedi?tricoGoes, Janaina da Silva 29 August 2013 (has links)
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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.
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An?lise n?o destrutiva da qualidade da madeira de Cedrela fissilis Vell. proveniente de restaura??o florestal no estado de S?o Paulo / Non-destructive analysis of wood quality of Cedrela fissilis Vell. from forest restoration in the state of S?o PauloSILVA, Carlos Eduardo Silveira 25 February 2016 (has links)
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Previous issue date: 2016-02-25 / CAPES / The research was conducted at Fazenda Sant'Ana do Monte Alegre, located in the municipality of Descalvado, S?o Paulo and its objective was to evaluate the wood quality of cedro rosa through non-destructive analysis and relate their development to the practice of forest restoration. We selected 24 cedro rosa individuals with 14 years of age and these were divided into three diameter classes (trees with a diameter less than or equal to 10 cm, trees with diameter between 10 and 20 cm and trees with diameter greater than 20 cm). Dendrometric analyzes were performed, of resistograph, extensometry, tomography and with the material obtained by increasing auger, densitometry X-ray and an estimated basic density was performed. It is noteworthy that the tomography scan was performed on individuals with a diameter larger than 20 cm, with this statement made by the appliance manual and professionals. The results of the analysis showed dendrometric respectively the regular annual average increase of 0,598 cm in diameter, 0,264 m in height and 0,014 m3 in volume in three years. The basic density obtained average value of 466,96 kg/m3 and the apparent density to 15%, performed by densitometry X-rays of 528,5 kg/m3. The densitometry accurately estimated the age of individuals. The extensometer averaged 0,0438mm of the respective longitudinal residual strain value and the tomography showed a mean value of wave propagation of 539,72 m/s, emphasizing that only 2 samples had considered variation in the plant health status of wood. The resistograph averaged amplitudes (percentage resistance of the wood with respect to the apparatus drill penetration) showed 10,591% for the three diameter classes. However it showed the presence of significant difference between the diameter Class I to Class II and III, possibly due to increased hardness of the material, the presence of tension and heating the appliance stem. It can be concluded that the quality of wood species studied showed potential for the timber industry from non-destructive analyzes. The diameter classes had significant statistical difference only in resistografia. The non-destructive methodologies demonstrated that some may correlate with the other non-destructive analysis. This information may be employed to study physical, mechanical properties and for the development of native species without the use of destructive sampling. / A pesquisa foi realizada na Fazenda Sant?Ana do Monte Alegre, localizada no munic?pio de Descalvado, S?o Paulo e seu objetivo foi avaliar a qualidade da madeira do cedro-rosa atrav?s de an?lises n?o destrutivas e relacionar o seu desenvolvimento ? pr?tica de restaura??o florestal. Selecionaram-se 24 indiv?duos de cedro-rosa com 14 anos de idade e estes foram separados em 3 classes diam?tricas (?rvores com di?metro menor ou igual a 10 cm, ?rvores com di?metro entre 10 e 20 cm de e ?rvores com di?metro maior que 20 cm). Foram realizadas an?lises dendrom?tricas, de resistografia, de extensometria, tomografia e, com o material obtido atrav?s do trado de incremento, foi realizada a densitometria de raios X e a estimativa da densidade b?sica. Ressalta-se que a tomografia foi realizada nos indiv?duos com di?metro maiores que 20 cm, sendo esta indica??o realizada pelo manual do aparelho e por profissionais da ?rea. Os resultados da an?lise dendrom?trica apontaram respectivamente o incremento peri?dico anual m?dio de 0,598 cm no di?metro, 0,264 m na altura e 0,014 m3 no volume em 3 anos. A densidade b?sica obteve o valor m?dio de 466,96 kg/m3 e a densidade aparente a 15%, realizada atrav?s da microdensitometria de raios-X de 528,5 kg/m3. A microdensitometria estimou com precis?o a idade dos indiv?duos. A extensometria apresentou valor m?dio de 0,044 mm de deforma??o residual longitudinal (relacionada ? presen?a de tens?es de crescimento no fuste) e a tomografia apresentou valor m?dio de propaga??o de ondas de 539,72 m/s. Somente 2 indiv?duos apresentaram considerada varia??o no estado fitossanit?rio da madeira. A resistografia apresentou valor m?dio de amplitudes (resist?ncia percentual apresentada pela madeira em rela??o ? penetra??o da broca do aparelho) de 10,591% para as tr?s classes diam?tricas. Por?m evidenciou-se a presen?a de diferen?a estat?stica entre a classe diam?trica I para as classes II e III, possivelmente devido a aumento da dureza do material, presen?a de tens?es e aquecimento da haste do aparelho. Pode-se concluir que a qualidade da madeira da esp?cie estudada demonstrou potencial para a ind?stria madeireira a partir das an?lises n?o destrutivas realizadas. As classes diam?tricas obtiveram diferen?a estat?stica significativa somente na resistografia. As metodologias n?o destrutivas utilizadas demonstraram que algumas podem se correlacionar com as demais an?lises n?o destrutivas podendo ser empregadas para o estudo de propriedades f?sicas, mec?nicas e para o desenvolvimento de esp?cies florestais nativas sem a utiliza??o da amostragem destrutiva.
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Degrada??o natural de toras e sua influ?ncia nas propriedades f?sicas e mec?nicas da madeira de cinco esp?cies florestais / Natural degradation of toras and your influence in the properties of the wood five forest speciesTrevisan, Henrique 22 February 2006 (has links)
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Previous issue date: 2006-02-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The first part of this work was led from August from 2004 to August 2005. The objective of
evaluating the influence of two enviroments: forest and open field, in the durability of recently
abated toras of five forest species: Eucalyptus urophylla " Eucalyptus " (Myrtaceae), Melia
azedarach L. " Cinamomo " (Meliaceae), Lophantera lactescens Ducke, Lanterneira
(Malpighiaceae), Pinus elliottii "Pinus" (Pinaceae), Inga marginata " Inga " (Mimosaceae), as
well as to evaluate the beetles and termites occurrence in the respective wood and enviroments,
through collections of wood sub-samples, in defione time, and of collections of the ocurrente
termites, in the dismantle of the experiment. The beetles occurrence were just registered in the
timber of Inga marginata and in the field from inside the forest, and the identified species were:
Euplatypus parallelus and Teloplatypus ratzeburgi, both of the family Platypodidae. 56,6% of the
timber were enrolled with the presence of termites in the field from inside thee forest, where the
species found were: Nasutitermes minor, Nasutitermes jaraguae and Heterotermes longiceps. In
the open field, it was registered 20% of the timber with the presence of termites, with a since
species found, Heterotermes longiceps. For the evaluation of the natural durability, a
classification system was adopted, where through the deterioration level, notes were attributed.
The smallest indexes, for both enviroment were registered by the timber of E. urophylla, 60
inside the forest and 70 of outside forest. The second part of this work had the objective of
evaluating the influence of the intemperism, in the physical and mechanical wood properties.
Mechanical rehearsals were accomplished with the wood non degradation, for further comparison
with the values obtained from the rehearsals accomplished in the wood coming from the
intemperized timber. Significant reductions of the density were observed only the exposed wood
from the rotten field of the forest. The wood of L. lactescnes was the only one that didn't show
the resistance from the compression and the module of elasticity and rupture, in the static flex,
altered after the intemperism, in the two enviroments. The largest reductions in the module of
elasticity and rupture, as well as in the resistance from compression, were registered in the wood
of E. urophylla, in both enviroments. The third part of this work had the objective of studing the
natural resistance of the wood, Coptotermes gestroi action, as well as to trace a discussion on the
methodologies that evaluate the resistance of the wood to termites and to propose a protocol that
contemplates the referred study, in a more appropriate way, and that can predict, in a more real
way, the resistance of the wood when in service. The wood that losis more mass, front the action
of C. gestroi was the L, lactescens and the one that loses less mass was M azedarach. E.
urophylla and L. lactescens were framed in the resistant class and M. azedarach and I.
marginata, as highly resistant to C. gestroi in the rehearsal of free choice. The suggested method,
denominated semicampo , was efficient for the evaluation of natural resistance of the wood
and feeding preference. / A primeira parte deste trabalho foi conduzida entre agosto de 2004 a agosto de 2005, e teve como
objetivo avaliar a influ?ncia de dois ambientes, florestal e campo aberto, na durabilidade de toras
rec?m abatidas de cinco esp?cies florestais: Eucalyptus urophylla Eucalipto (Myrtaceae),
Melia azedarach L. Cinamomo (Meliaceae), Lophantera lactescens Ducke, Lanterneira
(Malpighiaceae), Pinus elliottii Pinus (Pinaceae), Inga marginata Inga (Mimosaceae), bem
como avaliar a ocorr?ncia de coleobrocas e t?rmitas nas respectivas madeiras e ambientes,
atrav?s de coletas de sub-amostras de madeira, em tempo determinado, e de coletas dos t?rmitas
ocorrentes, na desmontagem do experimento. Foi registrada a ocorr?ncia de coleobrocas apenas
nas toras de Inga marginata e no campo de dentro da mata, sendo as esp?cies identificadas:
Euplatypus parallelus e Teloplatypus ratzeburgi, ambas da fam?lia Platypodidae. Registrou-se
56,6 % das toras com a presen?a de t?rmitas no campo de dentro da mata, sendo que as esp?cies
ocorrentes foram: Nasutitermes minor, Nasutitermes jaraguae e Heterotermes longiceps. No
campo a c?u aberto, foi registrado 20% das toras com a presen?a de t?rmitas, de uma ?nica
esp?cie ocorrente, Heterotermes longiceps. Para a avalia??o da durabilidade natural, adotou-se
um sistema de classifica??o. Os menores ?ndices de comportamento, o que denotam madeiras
mais degradadas, para ambos os ambientes, foram registrados nas toras de Eucalipto, sendo 60
para dentro da mata e 70 para fora da mata. A segunda parte deste trabalho teve como objetivo
avaliar a influ?ncia do intemperismo em propriedades f?sicas e mec?nicas da madeira. Ensaios
mec?nicos foram realizados com a madeira n?o intemperizada, para posterior compara??o com os
valores obtidos dos ensaios realizados nas madeiras procedentes das toras intemperizadas.
Redu??es significativas da densidade foram observadas apenas nas madeiras expostas no campo
de apodrecimento de dentro da mata. A madeira de L. lactescens foi a ?nica que n?o teve a
resist?ncia a compress?o e o m?dulo de elasticidade e ruptura, na flex?o est?tica, alterados ap?s o
intemperismo, nos dois ambientes. As maiores redu??es no m?dulo de elasticidade e ruptura,
bem como na resist?ncia a compress?o, foram registradas na madeira de E. urophylla, nos dois
ambientes. A terceira parte deste trabalho teve como objetivo estudar a resist?ncia natural das
madeiras, a a??o de Coptotermes Gestroi, bem como tra?ar uma discuss?o sobre as metodologias
que avaliam a resist?ncia da madeira a t?rmitas e propor um protocolo que contemple o referido
estudo, de forma mais adequada, e que possa predizer, de forma mais real, a resist?ncia da
madeira quando em servi?o. A madeira que mais perdeu massa, frente ? a??o de C. gestroi foi a
de L.lactecens e a que menos perdeu foi a de M. azedarach. A madeira de E. urophilla e L.
lactescens foram enquadradas na classe resistente e M. azedarach e I. marginata, como
altamente resistente a Coptotermes gestroi no ensaio de livre escolha. O m?todo sugerido,
denominado semicampo, demonstrou-se eficiente para avalia??o da resist?ncia natural das
madeiras e prefer?ncia alimentar.
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Estudo da adi??o do res?duo proveniente da extra??o de min?rio de ferro em argilas do Rio Grande do NorteChaves, Leonardo Flamarion Marques 30 October 2009 (has links)
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Previous issue date: 2009-10-30 / The mining industry is responsible for the generation of waste from their natural process of extraction. The mining impacts in urban areas are of special importance due to the high urban occupation, which are exacerbated due to the proximity of the mined areas and populated areas. Some solutions to wastedisposal have the potential to significantly reduce the environmental risks and liabilities, but represent higher costs in the stages of deployment and operation. The addition of mining waste as raw material in the development of commercial products reduces the environmental impacts, transforming the waste into a positive element in the generation of employment and income. This thesis studies the incorporation of waste iron ore in two clays, one from the ceramic industry of the City of Natal and the other from the ceramic industry of the Serid? Region, both in the State of Rio Grande do Norte, Brazil. Percentages of iron ore waste of 5%, 10% , 15%, 20%, 25% and 30% were used in the tested ceramic matrix. The two clays and the iron ore waste used as part of this investigation were characterized by X-ray diffraction tests, X-ray fluorescence tests, differential thermal analysis, thermogravimetric analysis and dilatometric analysis. The samples were sintered under temperatures of 850 ?C, 950 ?C and 1050?C at a heating rate of 5 ?C/min with isotherms of two hours. The following tests were performed with the samples: linear shrinkage, water absorption, apparent porosity, apparent density, mass loss in fire and bending resistance in order to obtain their physical and mechanical properties. An amount of 5% of waste iron ore in the matrix clay at a temperature of 850 0C resulted in na increase of about 65% in the tensile strength of the clay samples from the Natal ceramic industry. A linear shrinkage of only 0.12% was observed for the samples, which indicates that the physical properties of the final product were not influenced by the addition of the waste / A ind?stria extrativa mineral ? respons?vel pela gera??o de res?duos provenientes do seu processo natural de extra??o. Os impactos da minera??o em ?rea urbana revestem-se de especial import?ncia devido ao alto grau de ocupa??o urbana, que s?o agravados face ? proximidade entre as ?reas mineradas e as ?reas habitadas. Algumas solu??es de disposi??o de res?duos t?m potencial de reduzir significativamente os riscos e o passivo ambiental, por?m representam custos elevados nas etapas de implanta??o e de opera??o. A adi??o de res?duos de min?rio de ferro como mat?ria-prima na elabora??o de produtos que s?o utilizados comercialmente tem como objetivo diminuir os impactos ambientais, transformando esses res?duos em elementos positivos na gera??o de trabalho e renda. O presente trabalho estuda a incorpora??o de res?duo de min?rio de ferro em duas argilas, uma do p?lo cer?mico da Grande Natal e outra do p?lo cer?mico da Regi?o do Serid?, ambas do Estado do Rio Grande do Norte, em percentuais de 5%, 10%, 15%, 20%, 25% e 30%, com o intuito de verificar a potencialidade da incorpora??o do res?duo em matriz cer?mica. As mat?rias-primas foram caracterizadas atrav?s dos ensaios de difra??o de raios X, fluoresc?ncia de raios X, an?lise t?rmica diferencial, an?lise termogravim?trica e an?lise dilatom?trica. Os corpos-de-prova foram conformados e em seguida sinterizados nas temperaturas de 850 ?C, 950 ?C e 1050 ?C, ? taxa de aquecimento de 5 ?C/min, com iso terma de duas horas. Foram realizados os ensaios tecnol?gicos de retra??o linear de queima, absor??o de ?gua, porosidade aparente, massa espec?fica aparente, perda demassa ao fogo e tens?o de ruptura ? flex?o, com o intuito de se obter suas propriedades f?sicas e mec?nica. A argila do p?lo cer?mico da Grande Natal apresentou um aumento em torno de 65% na tens?o de ruptura ? flex?o, com um percentual ?nfimo de 0,12% na sua retra??o linear de queima, quando adicionados 5% de res?duo de min?rio de ferro na matriz de argila ? temperatura de 850 ?C, n?o comprometendo assim as p ropriedades f?sicas do produto final
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Obten??o de uma porcelana diel?trica a partir de mat?rias-primas do Rio Grande do NorteSilva, Elialdo Chib?rio da 26 March 2010 (has links)
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Previous issue date: 2010-03-26 / Universidade Federal do Rio Grande do Norte / The dielectric porcelain is usually obtained by mixing various raw materials proportions and is used in the production of electronic equipment for various applications, from capacitors of high and low Power to insulators for low, medium, high and extra high voltage, which are used in distribution lines and transmission of electricity.This work was directed to the s tudy of technological properties of technic porcelain, made from raw materials extracted from pegmatites found in the regions of Serid? and the Alto Oeste of Rio Grande do Norte, which are made of kaolin, quartz and feldspar, abundant and high quality in these regions. The technic ceramics were obtained by mixing in appropriate levels, kaolin, feldspar, quartz and clay, the last item
from a pottery in the city of Sao Gon?alo do Amarante, Rio Grande do Norte. During the development the following characterizations correlated to raw materials were made: laser particle sizing, x-ray diffraction, DTA and TG. The compositions studied were formed by uniaxial pressing at a pressure of 50 MPa and sintered at temperatures ranging from 1150 to 1350?C and levels (times) of sintering between 30, 60, 90 and 120 minutes. The characterization of the samples were taken from the analysis of weight loss, linear shrinkage, porosity, stoneware curve, bulk density, flexural strength of three points, SEM and X-ray diffraction, TMA, Dielectric and cross Resistivity. The studied materials can be employed in producing the objects used in electrical engineering such as: insulators for low, medium and high-voltage electrical systems, command devices, bushing insulation for transformers, power capacitors, spark plugs, receptacles for fluorescent and incandescent light bulbs and others / A porcelana diel?trica ? normalmente obtida atrav?s da mistura de diferentes mat?rias-primas, em propor??es adequadas, sendo utilizada na produ??o de equipamentos eletroeletr?nicos de diversas aplica??es, desde capacitores de alta e baixa pot?ncia, a isoladores para baixa, m?dia, alta e extra alta tens?o, que s?o utilizados em linhas de distribui??o e transmiss?o de energia el?trica. Neste trabalho, s?o estudadas as propriedades tecnol?gicas de uma porcelana diel?trica, formulada a partir de mat?rias-primas obtidas de pegmatitos encontrados nas regi?es do Serid? e do Alto Oeste do Rio Grande do Norte, sendo estas constitu?das de caulim, quartzo e feldspato, abundantes e de alta qualidade nestas regi?es, e de uma argila proveniente de uma cer?mica situada no munic?pio de S?o Gon?alo do Amarante, tamb?m no Estado do Rio Grande do Norte. As mat?rias-primas foram caracterizadas atrav?s de: granulometria a laser, difra??o de raios X, an?lise t?rmica diferencial e an?lise termogravim?trica. As amostras foram conformadas por prensagem uniaxial a uma press?o de 50 MPa, e sinterizadas ?s temperaturas de 1150, 1200, 1250, 1300 e 1350 ?C, com patamares de sinteriza??o de 30, 60, 90 e 120 minutos. Os ensaios tecnol?gicos realizados foram: an?lise da perda de massa, retra??o linear, porosidade, curva de gressifica??o, microscopia eletr?nica de varredura, difra??o de raios X, dilatometria, rigidez diel?trica, resistividade transversal e permissividade diel?trica. Os melhores valores de propriedades foram obtidos na temperatura de 1250 ?C, para as composi??es estudadas, n?o sofrendo varia??es significativas em seu comportamento com o tempo de sinteriza??o. Os materiais estudados podem ser empregados na obten??o de objetos usados em eletrot?cnica como por exemplo: isoladores de baixa, m?dia e alta-tens?o para redes el?tricas, dispositivos de comando, bucha de isolamento de transformador, capacitores de pot?ncia, vela de igni??o, recept?culos de l?mpadas incandescentes e fluorescentes e outros
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