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Examining the Role of P53 in Radiation-Induced Mutations at ESTR Loci / The Role of P53 in Radiation-Induced ESTR MutationsLanglois, Nicole 09 1900 (has links)
It is well known that ionizing radiation is genotoxic, and can trigger heritable mutations in the germ cells of an animal. Recently, researchers have used hypervariable expanded simple tandem repeat (ESTR) regions of DNA to explore this phenomenon. ESTRs facilitate the examination of induced genetic mutations using relatively low radiation doses and fewer mice than more traditional approaches. Numerous studies have examined the responses of ESTRs to radiation in the germ line; however the mechanism behind germ line mutations at ESTR loci is poorly understood. Current hypotheses propose that error-prone DNA repair, which allows for misalignment of DNA strands through replication slippage produces in changes in ESTR size. P53 is involved in DNA replication as well as repair of DNA damage, apoptosis and other cancer-related processes. We use p53-deficient heterozygous male mice to examine the role of p53 in germ line mutations at ESTR loci. Males were irradiated with a variety of dose combinations both prior to and post-meiosis, and were mated to unirradiated wildtype females. DNA from the adults and offspring was analyzed for mutations at ESTR loci using DNA fingerprinting. Surprisingly, the study found no significant differences in germ line mutation rate between any treatment groups, including the 0Gy and 1Gy treatments. I discuss the possibility that these results are due to the p53 deficiency of the males, and that p53 homozygosity is necessary for radiation-induced germ line mutations at ESTR loci to occur. I conclude that further studies need to be done, including a control study using wildtype males of the same background strain as that of the p53 deficient line in order to verify our results. / Thesis / Master of Science (MS)
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Purchasing power parity and the dynamic adjusting behavior of short-term nominal exchange rateChen, I-Hsiu 05 July 2010 (has links)
Purchasing power parity (PPP) is considered as an important theory of explaining how
exchange rate varies in the long run. Most of empirical studies in the past adapted linear
cointegration method to test the purchasing power parity. However, there are papers point out
that exchange rate exists non-linear cointegration and unexplainable bias might exist in testing
the purchase power parity theory while using linear cointegration test. The methodology of
this study is based on an application of ESTR ECM proposed by Kapetaniosetet al. to enhance
the inadequate of linear cointegration test.
We analyze the dynamic adjusting behavior of short-term nominal exchange rate with ESTR
ECM model while the non-linear cointegratoin exists. The empirical result indicates that the
purchase power parity between Taiwan and its major trading countries is confirmed. Among the
trading countries, American, Japan and Hong Kong are suitable for using linear error correction
model and non-linear error correction model for Singapore and Korea.
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noneLin, Yu-cheng 30 June 2009 (has links)
Abstract
Divident discount model found further expected dividend discounting to some fix period. The dividends are determined from the the core of company and relates retain earning. In Taiwan stock market, divedneds are not paid per season. So, I adept earning per share to proxy variable and employ market value weight to conduct dividends for Taiwan stock idnex. The next step,
investgate the relationship between price index and diviednds using the econometric model was created by Kapetanios et al. (2006). Consequencely, the relationship are fitted discribtion by ESTR cointegration rather than linear cointegration.
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noneChen, Chi-chang 30 June 2009 (has links)
The methodology is based on an application of nonlinear ESTR ECM by Kapetanios et al.
(2006) to analyze the short-run dynamic adjustment to long-run equilibrium in Taiwan money
demand function. We take consideration of Taiwan as a small open economy system, the exchange
rate could be included in money demand function. The result indicate that using ESTR
ECM to analyze the adjustment behavior of money demand function in Taiwan is better than
linear ECM. Our findings point out that the public adjusts at any time for holding money and
the speed of adjustment for real balances depends on the size of deviation.
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Um Estudo Sobre Verbo Suporte na Construção de Dar + SnDAVEL, A. P. C. 07 March 2009 (has links)
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Previous issue date: 2009-03-07 / Esta dissertação tem como objetivo apresentar um estudo sobre as estruturas com verbosuporte DAR+SN no português do Brasil, a partir da Teoria Lexical e dos princípios do Léxico-Gramática. São examinadas as propriedades distribucionais dessa estrutura, em contextos de uso da língua, por meio de critérios formais que levam em conta os aspectos morfossintáticosemânticos, distinguindo-se a estrutura com verbo pleno de verbo suporte e de expressões cristalizadas. As estruturas com verbo suporte são de natureza denominal e deverbal. De modo geral, as denominais denotam ações de golpe como, por exemplo, dar uma pedrada e as deverbais apresentam atenuação e brevidade das ações como, por exemplo, dar uma olhada. Os estudos revelam que as estruturas DAR uma X-ada são também utilizadas como formas modalizadoras da linguagem, constituindo um recurso de expressividade por parte dos falantes nativos.
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Dimorfismo sexual no modelo de infarto do mioc?rdio em ratos: aspectos neuroend?crinos e auton?micos cardiovascularesSOUZA, Natalia Soares Carvalho de 26 August 2014 (has links)
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Previous issue date: 2014-08-26 / CAPES / Premenopausal women are less prone to develop cardiovascular diseases than men and this advantage do not persist in postmenopausal women. Thus herein we aimed to investigate the gender difference and the estrogen influence in cardiac function, fluid balance and thyroid status, in Wistar rats subjected to experimental model of myocardial infarction (MI).
In the first step, adult male (n = 18) and female (n = 21) rats underwent experimental MI (MIm and MIf,) or sham-operation (ShamM and ShamF) respectively. One and four weeks post-MI rats were placed in metabolic cages, subjected to echocardiography (ECHO), electrocardiography and then euthanized for blood sample collection and tissue collection (heart, lung and liver). In the second step female rats were ovariectomized (n = 24) or continued intact (n = 21), two weeks later they were subjected to MI (MIOVX and MIINT, respectively) or sham operation (ShamOVX and ShamINT). Four weeks post-MI, they were subjected to the same evaluations of the first step, not only the electrocardiography. In the third step, female rats were subjected to ovariectomy and treated with estrogen (E2) (n = 13) or vehicle (n = 22). Two weeks later they underwent experimental MI (MIOVX+E2 and MIOVX+Veh). Four weeks post-MI they were subjected to the same evaluations of the second step.
Male infarcted rats developed cardiac dysfunction (shortening fraction, SF, reduction, ~ 70%) and fluid homeostasis changes (sodium intake increasing, ~ 146% and urinary volume reduction, ~55%) earlier than female, in the first week post-MI while female presented these changes (SF reduction, ~28% and sodium intake increasing, ~143%) only in the fourth week and attenuated compared to male. MIM showed reduction in LF/HF ratio (~70%), one week post-MI. And only male rats presented hypothyroidism after MI (T4 ~52% and T3 ~38%, reduction). We also verified reduction in SF (~55%), increasing in LA/Ao ratio (~75%) and changes in fluid balance (sodium intake reduction, ~67% and urinary volume reduction, ~40%) more pronounced in MIOVX than in MIINT. MIOVX group reduced thyroid hormone levels after MI (T3 ~35%). MIOVX+Veh showed more pronounced reduction in SF (~55%) and increasing in LA/Ao ratio (~75%) than the MIOVX+E2 group. The sodium intake reduced in MIOVX+Veh (~67%) and in the urinary volume we verified significant reduction in ShamOVX+Veh and MIOVX+Veh groups compared to ShamOVX+E2 and MIOVX+E2 groups (P < 0.05). Serum T3 reduced significantly (~35%) only in MIOVX+Veh group.
The pathophysiological development of heart failure post-MI was attenuated in female compared to male. And female rats subjected to MI presented fluid balance more favorable and related to the less pronounced development of heart failure. Estrogen seems to influence positively the cardiac function and attenuate the dysfunction that occur post-MI. The euthyroid status in female intact do not seems to be determinant to the less pronounced development of heart failure. / Sabe-se que mulheres na pr?-menopausa apresentam menor preval?ncia de doen?as cardiovasculares do que homens e, esta diferen?a desaparece ap?s a menopausa. Sendo assim, o presente estudo buscou avaliar o dimorfismo sexual e a influ?ncia do estr?geno nas altera??es da fun??o card?aca, do equil?brio hidroeletrol?tico e do status tireoidiano de ratos Wistar submetidos ao infarto do mioc?rdio (IM) experimental.
Na primeira etapa ratos wistar machos (n = 18) e f?meas (n = 21) foram submetidos ao infarto experimental (INF.M e INF.F) ou ? falsa cirurgia (Sham.M e Sham.F). Na primeira e quarta semana p?s-IM foram colocados em gaiolas metab?licas e submetidos ? ecodopplercardiografia (ECO) e eletrocardiografia (an?lise espectral), seguido de eutan?sia para coleta de sangue (dosagem s?rica de horm?nios tireoidianos) e de tecidos (cora??o, pulm?o e f?gado, para biometria). Na segunda etapa, f?meas foram ovariectomizadas (n = 24) ou mantidas intactas (n = 21) e ap?s duas semanas submetidas ao infarto do mioc?rdio (INFOVX e INFINT) ou ? falsa cirurgia (ShamOVX e ShamINT). Quatro semanas ap?s p?s-IM, as mesmas avalia??es da etapa anterior foram realizadas exceto a eletrocardiogr?fica. Na terceira etapa, foi realizada ovariectomia e reposi??o com estr?geno (E2) ( n = 13) ou ve?culo (n = 22). Ap?s duas semanas foi realizada a cirurgia de indu??o ao infarto (INFOVX+E2 e INFOVX+Veic) e a falsa cirurgia (ShamOVX+E2 e ShamOVX+Veic). Decorridas quatro semanas foram feitas as mesmas avalia??es da segunda etapa.
O grupo INFM desenvolveu disfun??o card?aca (fra??o de encurtamento, FEnc%, ~70% de redu??o) e altera??es na regula??o hidroeletrol?tica (aumento do apetite por s?dio, ~146% e redu??o do volume urin?rio, ~55%), uma semana p?s-IM e, portanto, mais cedo que as f?meas, que apresentaram altera??es na fun??o card?aca (FEnc%, ~28% de redu??o) e regula??o hidroeletrol?tica (aumento do apetite por s?dio, ~143%) na quarta semana p?s-IM. O grupo INFM apresentou redu??o na rela??o LF/HF (~70%), uma semana p?s-IM. E, apenas os ratos machos desenvolveram hipotireoidismo ap?s o infarto. Tamb?m foi observada redu??o da FEnc% (~55%), aumento da rela??o ?trio esquerdo/ aorta (AE/Ao, ~75%) e altera??es na regula??o hidroeletrol?tica (redu??o do apetite por s?dio, ~67% e do volume urin?rio, ~40%) mais pronunciadas em INFOVX do que em INFINT. O grupo INFOVX tamb?m apresentou redu??o dos n?veis s?ricos de T3 (~35%) p?s-IM. O grupo INFOVX+Vei mostrou redu??o da FEnc% (~55%) e aumento na rela??o AE/Ao (~75%) mais pronunciadas que o grupo INFOVX+E2. INFOVX+Vei reduziu o apetite por s?dio (~67%) e, no volume urin?rio, foi observada redu??o significativa nos grupos ShamOVX+Vei e INFOVX+Vei em rela??o aos grupos ShamOVX+E2 e INFOVX+E2 (P<0,05). O T3 s?rico reduziu significativamente (~35%) apenas no grupo INFOVX+Vei. Houve diferen?a no desenvolvimento fisiopatol?gico da insufici?ncia card?aca (IC) p?s-IM entre machos e f?meas, sendo mais brando nas f?meas. E f?meas infartadas apresentaram uma regula??o hidroeletrol?tica mais favor?vel e compat?vel com o desenvolvimento menos acentuado da IC. O estr?geno influenciou positivamente a regula??o hidroeletrolitica de f?meas infartadas, o que favoreceu a fun??o card?aca e atenuou desta forma, a disfun??o que ocorre ap?s o infarto. A manuten??o do status eutire?ideo n?o pareceu ser determinante para o desenvolvimento menos pronunciado da IC.
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Efeitos de diferentes tipos estressores sobre a mem?ria e aprendizagem de ratasNascimento, Ezequiel Batista do 12 July 2013 (has links)
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Previous issue date: 2013-07-12 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The exposure to stressors produces physiological changes of the
organism in order to adapt the individual to the environment. Depending on the
type, intensity and duration, stress can affect some cognitive functions,
particularly processes of learning and memory. Several studies have also
proposed that some level of anxiety would be necessary for memory formation.
In this context, memories of previously aversive experiences may determine the
manner and intensity with which are expressed fear responses, which explains
the great interest in analyzing both anxiety and memory in animals. In addition,
males and females demonstrate different reactions in relation to stressful
stimuli, showing different levels of anxiety and differences in processing of the
acquisition, retention and recall of information.
Based on this information, the present study aimed to verify the effect of
stress on learning, memory and anxiety behavioral parameters in rats exposed
at different types of stressors of long duration (seven consecutive days):
restraint (4h/day), overcrowding (18h/day) and social isolation (18h/day) in the
different phases of the estrous cycle. Our results showed that the stress
induced by restraint and social isolation did not cause changes in the
acquisition process, but impaired the recall of memory in rats. Furthermore, it is
suggested a protective effect of sex hormones on retrieval of aversive memory,
since female rats in proestrus or estrus phase, characterized by high estrogen
concentrations, showed no aversive memory deficits. Furthermore, despite the
increased plasma levels of corticosterone observed in female rats subjected to
restraint stress and social isolation, anxiety levels were unaltered, compared to
those various stress conditions.
Animal models based on psychological and social stress have been
extensively discussed in the literature. Correlate behavioral responses,
physiological and psychological have contributed in increasing the
understanding of stress-induced psychophysiological disorders / A exposi??o a fatores estressantes promove mudan?as fisiol?gicas
adaptativas do organismo ao meio ambiente. Dependendo do tipo, da
intensidade e dura??o, o estresse pode afetar algumas fun??es cognitivas,
particularmente o processo de aprendizagem e de mem?ria. Alguns estudos
tamb?m t?m proposto que a ansiedade, em certa medida, seria necess?ria
para que ocorresse a forma??o da mem?ria. Neste contexto, mem?rias de
experi?ncias aversivas anteriores podem determinar a maneira e a intensidade
com que s?o expressas as respostas de medo, o que justifica o grande
interesse em analisar simultaneamente ansiedade e mem?ria em animais. No
mais, machos e f?meas apresentam rea??es distintas em rela??o a est?mulos
estressores, mostrando diferentes n?veis de ansiedade e diferen?as no
processamento da aquisi??o, reten??o e evoca??o de informa??es
mnem?nicas.
Frente a essas informa??es, o presente estudo teve como objetivo
verificar o efeito do estresse em par?metros comportamentais de
aprendizagem, mem?ria e ansiedade de ratas submetidas a diferentes tipos de
estressores de longa dura??o, (sete dias consecutivos): conten??o (4h/dia),
alta densidade populacional (18h/dia) e isolamento social (18h/dia), nas
diferentes fases do ciclo estral. Nossos resultados mostraram que o estresse
promovido pela conten??o e pelo isolamento social n?o promoveram altera??es
no processo de aquisi??o, mas promoveu preju?zos na evoca??o da mem?ria
de ratas. Al?m disso, sugere-se um efeito protetor dos horm?nios sexuais
sobre a evoca??o da mem?ria aversiva, uma vez que ratas que estavam nas
fases proestro ou estro, fase de altas concentra??es plasm?ticas de
estr?genos, n?o apresentaram preju?zos na evoca??o dessa mem?ria. No
mais, apesar do aumento dos n?veis plasm?ticos de corticosterona observado
nas ratas submetidas ao estresse de conten??o e isolamento social, os n?veis
de ansiedade permaneceram inalterados frente a essas diferentes condi??es
de estresse.
Modelos animais baseados em estresse psicol?gico e social t?m sido
bastante abordados na literatura. Correlacionar respostas comportamentais,
fisiol?gicas e psicol?gicas t?m contribu?do no aumento da compreens?o dos
transtornos psicofisiol?gicos envolvidos na resposta de estresse
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Importancia de los receptores estrog��nicos en el estr��s oxidativo y el c��ncer. Funci��n, biog��nesis y din��mica mitocondrialSastre Serra, Jorge 27 July 2012 (has links)
El 17��-estradiol (E2) es un factor de riesgo tanto en la iniciaci��n como en la progresi��n de c��nceres hormonodependientes. El E2 modula el estr��s oxidativo afectando, entre otras, a la proliferaci��n celular y por tanto en el proceso tumorig��nico.
Los objetivos de la presente tesis fueron, estudiar la acci��n de las hormonas sexuales en la modulaci��n del estr��s oxidativo en las c��lulas cancerosas, y el estudio de la importancia del balance de los receptores estrog��nicos alfa y beta (ER�� y ER��) en la acci��n del E2 en la funci��n, la biog��nesis y la din��mica mitocondrial, as�� como en el control del estr��s oxidativo.
Los resultados obtenidos en la presente tesis la importancia de la acci��n de E2 a trav��s de los diferentes receptores sobre el estr��s oxidativo, la funci��n, la din��mica y la biog��nesis mitocondrial, tanto en l��neas celulares como en tumores de mama.
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Estudo da adsor??o do c?lcio e estr?ncio da ?gua produzida utilizando carv?o baba?u / A study on adsorption of calcium and strontium from produced water by using babassu charcoalMedeiros, Hena Lissa de Sousa 30 June 2015 (has links)
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Previous issue date: 2015-06-30 / Ag?ncia Nacional do Petr?leo - ANP / A ?gua produzida ? um dos principais res?duos gerados durante a explora??o e produ??o de petr?leo, devido ao grande volume e a sua composi??o qu?mica complexa surge ? preocupa??o para que as concentra??es dos contaminantes atendam as legisla??es vigentes, com a finalidade de reduzir os efeitos nocivos ao meio ambiente provocado pelo seu descarte sem tratamento pr?vio. Assim, o objetivo deste trabalho ? caracterizar a ?gua produzida no Campo de Periquito, do Estado do RN e avaliar o potencial adsortivo do carv?o vegetal de coco baba?u para remo??o dos metais Ca e Sr da ?gua produzida, visando a sua adequa??o para descarte. Atrav?s da caracteriza??o f?sico-qu?mica da ?gua produzida, p?de-se observar que as concentra??es dos metais c?lcio e estr?ncio foram: 322 mg/L e 69 mg/L, respectivamente. O material a ser utilizado como adsorvente foi caracterizado por diferentes t?cnicas f?sico-qu?micas, tais como: granulometria, densidade aparente, an?lise elementar, an?lise t?rmica, FRX, MEV, DRX e pHPZC. De posse das an?lises das caracteriza??es foram realizados ensaios de adsor??o, pelo m?todo de banho finito em solu??es sint?ticas dos metais Ca e Sr. Os resultados demonstraram que o carv?o baba?u possui remo??o m?xima em baixas concentra??es. Paralelamente ao estudo de adsor??o em solu??es sint?ticas, foi realizado ensaios de adsor??o com a ?gua produzida e o resultado mostrou que o carv?o baba?u possui bom potencial de adsor??o, removendo acima de 50 % do c?lcio e acima 45 % do estr?ncio, e apresentando valores para a capacidade de adsor??o de 17,31 mg/g para o c?lcio e 3,15 mg/g para o estr?ncio. Para otimizar os ensaios de adsor??o foi aplicado o planejamento fatorial completo de dois n?veis com o intuito de verificar a influ?ncia da concentra??o dos metais Ca e Sr e a massa do adsorvente em solu??o sint?tica sobre a % remo??o e a capacidade de adsor??o dos metais. Atrav?s dos resultados das an?lises das superf?cies de respostas p?de-se observar que as regi?es ?timas para a remo??o dos metais foram no n?vel superior da concentra??o dos metais e no n?vel superior da massa de adsorvente (+1,+1) obtendo uma remo??o m?xima de 58 % do c?lcio e 63 % do estr?ncio. / Produced water is a major waste generated during oil exploration and production. Due to its large volume and complex chemical composition an effort arises so that the contaminant concentrations meet the current legislation, in order to reduce harmful effects on the environment caused by its disposal without prior treatment. The objective of this paper is to characterize produced water from the Periquito field, RN, Brazil, and assess the adsorptive potential of babassu nut charcoal for removal of calcium and strontium from produced water, focusing on its suitability for disposal. Through the physicochemical characterization of the produced water, it was possible to observe that the concentrations of calcium and strontium were: 322 mg/L and 69 mg/L, respectively. The material to be used as an adsorbent was characterized through different physicochemical techniques, such as laser particle size, density, elemental analysis, thermal analysis, XRF, SEM, XRD and pHPZC. Provided the characterization analysis, adsorption experiments were carried out using the method of finite bath in synthetic solutions of both calcium and strontium. The results showed that babassu nut charcoal has maximum adsorption removal at low concentrations. In parallel with the study on adsorption in synthetic solutions, adsorption experiments were performed with produced water, whose results showed that babassu nut charcoal has good adsorption potential, removing over 50% of calcium and above 45% strontium, and having values of 17.31 mg/g for the adsorption capacity for calcium and 3.15 mg/g for strontium. In order to optimize the experiments, the full factorial design of two levels was applied in order to verify the influence of the concentration of calcium, strontium and the mass of the adsorbent in synthetic solution on the percentage of removal (%) and the adsorption capacity of adsorption of these metals. From the analysis results, it was possible to observe that the optimal regions for the removal of these metals was in the upper level of the metal concentration and in the upper level of the adsorbent mass (+1, +1) obtaining a maximum removal of 58 % for calcium and 63 % for strontium.
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S?ntese e caracteriza??o do Molibdato de Estr?ncio obtido a partir do m?todo de complexa??o combinado EDTA/Citrato para degrada??o fotocatal?tica de corante da ind?stria t?xtil / Synthesis and characterization of Strontium molybdate obtained from the Complexation Method Combining EDTA/Citrate for photocatalytic degradation dye the textile industrySilva, Mait? Medeiros de Santana e 26 August 2016 (has links)
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Previous issue date: 2016-08-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Este trabalho descreve o planejamento experimental 2? com triplicata no ponto central para produ??o do molibdato de estr?ncio (SrMoO4) atrav?s do m?todo de complexa??o combinado EDTA/Citrato onde investigou-se a influ?ncia do pH (6, 7,5 e 9), tempo de calcina??o (3, 4 e 5h) e taxa de aquecimento (5, 7 e 10?C.min-1) em alguns de seus par?metros qu?micos e f?sicos. Com base na curva de termogravim?trica os p?s de SrMoO4 foram calcinados a 650?C.Os materiais sintetizados foram caracterizados por TG/DSC, DRX, EDX, MEV e ERD. Os par?metros de rede da estrutura cristalina foram obtidos com base no m?todo de refinamento Rietveld. Todos os padr?es de DRX foram indexados segundo a ficha JCPDS 01-085-0586, com estrutura tetragonal e grupo espacial I41/a e o par?metro residual do refinamento da estrutura variou entre 1,035 a 1,292, n?o sendo identificadas fases secund?rias e impurezas. Constatou-se a exist?ncia de diferen?as entre as intensidades relativas m?dias dos picos de difra??o de raios-x. Atrav?s de ferramentas estat?sticas, concluiu-se que a taxa de aquecimento foi a vari?vel independente que demonstrou maior influ?ncia nessa diferen?a. As analises de EDX mostraram a presen?a de desvios entre a composi??o te?rica e experimental para os elementos estr?ncio e molibd?nio; o desvio percentual variou de 0,027 a 3,67% em fun??o das condi??es de s?ntese. De acordo com as micrografias obtidas por MEV, os p?s sintetizados s?o compostos de aglomerados de part?culas, com morfologia esf?ricas irregulares e bipiramidais. De acordo com a an?lise do planejamento experimental, tendo como vari?vel dependente a energia de bandgap, os menores valores obtidos (4,18 e 4,17 eV para pH 6 e 9, respectivamente) foram as amostras calcinadas por 3h com taxa de aquecimento igual a 10?C.min-1 em compara??o aos materiais calcinados nas demais condi??es de s?nteses e os modelos estat?sticos gerados se mostraram capazes de descrever os fen?menos observados. Testes explorat?rios na fotodegrada??o da solu??o sint?tica do corante azul de metileno utilizando o material com Egap de 4,17 eV indicam que o p? testado apresenta influ?ncia na diminui??o da concentra??o do corante para os testes realizados em pH 2 e 5 obtendo aproximadamente 95% e 24% de convers?o respectivamente, e para os teste em pH 9 observou-se que a fot?lise direta ? mais efetiva na redu??o da concentra??o do corante alcan?ando em torno 67% de convers?o, por?m o processo reacional necessita ser mais estudado para melhor compreens?o dos resultados. / This work describes the 2? experimental design with center point in triplicate for the production of strontium molybdate (SrMoO4) through complexation combined Citrate/EDTA method where investigated the influence of pH (6, 7,5 and 9), time calcination (3, 4 and 5 h) and heating rate (5, 7 and 10?C min-1) in some of its chemical and physical parameters. Based on thermogravimetric curve of SrMoO4 powders were calcined at 650?C. The synthesized materials were characterized by TG/DSC, XRD, EDX, SEM and ERD. The lattice parameters of the crystal structure were obtained from the Rietveld refinement method. All the XRD patterns were indexed according to JCPDS 01-085-0586 record with tetragonal structure and space group I41/a and the residual parameter structure refinement ranged from 1.035 to 1.292, secondary phases and impurities not being identified. It was found that there are differences between the average relative intensities of the diffraction peaks of X-rays. Using statistical tools, it was found that the rate of heating was the independent variable showed the greatest influence on this difference. The EDX analysis showed the presence of deviations between the theoretical and experimental composition for strontium and molybdenum components; the percentage deviation ranged from 0.027 to 3.67% depending on the conditions of synthesis. According to the SEM micrographs, the synthesized powders are composed of agglomerates of particles with irregular and spherical morphology bipiramidal. According to the analysis of the experimental design, with the dependent variable bandgap energy, the lowest values (4.18 and 4.17 eV to pH 6 and 9, respectively) were the samples calcined for 3 hours at the same heating rate 10 C min-1 compared to the calcined material in other conditions of synthesis and the statistical models generated have been shown to describe the observed phenomena. Exploratory testing photodegradation of the synthetic solution of methylene blue dye using the material bandgap of 4.17 eV indicate that the tested powder has influence on the reduction of dye concentration for tests carried out in pH 2 and 5 getting approximately 95% and 24 % conversion respectively, and the test at pH 9 it was noted that direct photolysis is more effective in reducing the dye concentration reached around 67% conversion, but the reaction process needs more study to better understand the results.
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