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Avalia??o do estado nutricional relativo ao sel?nio e da express?o g?nica de selenoprote?nas em pacientes com aterosclerose tratados com estatinas / Assessment of nutritional status of selenium and gene expression of selenoproteins in patients with atherosclerosis treated with statinsFerreira, Diana Quit?ria Cabral 24 May 2010 (has links)
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Previous issue date: 2010-05-24 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The aim of this study was to determine the effects of the use of rosuvastatin in patients with
atherosclerosis, in relation to blood parameters of selenium and selenoproteins, and also
observe possible changes in gene expression of selenoproteins in these patients. The sample
consisted of 27 adult and elderly patients with a clinical diagnosis of coronary artery disease
undergoing angioplasty, treated at Natal Hospital Center hospital, Natal, RN. Patients were
treated with rosuvastatin 10 mg/day during four months. Anthropometric variables such as
body mass index (BMI) and Waist circumference (WC) were measured before and after
treatment, as well as lipid profile, blood glucose and liver enzymes (AST and ALT). The diet
of the patients was also analyzed using 24-hour diet recall. We analyzed the concentrations of
selenium in plasma and erythrocytes, and also the activity of Glutathione Peroxidase and gene
expression by Real Time PCR of selenoproteins GPx1, SelP1 and SelN1. Patients had mean
age of 61.0 ? 9.4 years, 59.3% were men and 40.7% were women. After four months of
treatment there was significant reduction of CA and, according to BMI, most were
overweight. The intake of macronutrients, cholesterol, polyunsaturated fatty acids,
monounsaturated and saturated was adequate, but the energy and fiber intake was below
the recommendations. Regarding the selenium intake was observed a high prevalence of
inadequacy. As expected, after treatment with rosuvastatin, a significant reduction in total
cholesterol, LDL and glucose, which was not observed for HDL. Selenium concentrations
in plasma and erythrocytes showed no changes, keeping within the established cutoffs. We
observed a significant increase in GPx enzyme activity and mRNA expression of GPX1 and
SEPN1, but not for gene SEPP1. Thus, it was found that treatment with rosuvastatin did not
reduce the expression of selenoproteins. More studies are needed to clarify the effects of
rosuvastatin on gene expression of selenoproteins in patients with atherosclerosis / Este trabalho tem como objetivo verificar os efeitos do uso da rosuvastatina em pacientes com
aterosclerose, em rela??o aos par?metros sangu?neos de sel?nio e selenoprote?nas, bem como
observar poss?veis altera??es na express?o g?nica de selenoprote?nas nesses pacientes. A
amostra foi constitu?da de 27 pacientes adultos e idosos com o diagn?stico cl?nico de doen?a
arterial coronariana submetidos ? angioplastia, atendidos no Natal Hospital Center, Natal, RN.
Os pacientes foram tratados com 10mg/dia de rosuvastatina durante 4 meses. Vari?veis
antropom?tricas, como ?ndice de Massa Corporal (IMC) e Circunfer?ncia Abdominal (CA),
foram medidas antes e ap?s o tratamento, bem como o perfil lip?dico, glicemia e enzimas
hep?ticas (AST e ALT). A dieta dos pacientes tamb?m foi analisada utilizando o Recordat?rio
alimentar de 24 horas. Foram analisadas as concentra??es do sel?nio no plasma e nos
eritr?citos, e tamb?m a atividade da enzima Glutationa Peroxidase e a express?o g?nica por
PCR em Tempo Real das selenoprote?nas GPx1, SelP1 e SelN1. Os pacientes apresentaram
idade m?dia de 61,0?9,4 anos, sendo 59,3% homens e 40,7% mulheres. Ap?s os quatro meses
de tratamento observou-se redu??o significativa da CA e, de acordo com o IMC, a maior parte
estava com sobrepeso. A ingest?o dos macronutrientes, colesterol, ?cidos graxos
polinsaturados, monoinsaturados e saturados foi adequada, por?m a de energia e fibras estava
abaixo das recomenda??es. Com rela??o a ingest?o de sel?nio foi observada uma alta
preval?ncia de inadequa??o. Como esperado, ap?s o tratamento com a rosuvastatina, houve
redu??o significativa do colesterol total e LDL, bem como da glicemia, o que n?o foi
observado para o HDL. As concentra??es de sel?nio no plasma e eritr?citos n?o apresentaram
altera??es, se mantendo dentro dos pontos de corte estabelecidos. Foi observado um aumento
significante na atividade enzim?tica da GPx e na express?o de mRNA do GPX1 e SEPN1,
mas n?o para o gene SEPP1. Dessa forma, foi verificado que o tratamento com a
rosuvastatina n?o diminuiu a express?o das selenoprote?nas. Mais estudos s?o necess?rios
para esclarecer os efeitos da rosuvastatina sobre a express?o g?nica de selenoprote?nas em
pacientes com aterosclerose
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Efeitos do enriquecimento com nutrientes (N e P) em diferentes condi??es de luz sobre o crescimento do fitopl?ncton em um reservat?rio eutr?fico no semi-?rido brasileiroAra?jo, Fabiana Oliveira de 06 April 2009 (has links)
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Previous issue date: 2009-04-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The increasing of pollution in aquatic ecosystems in the last decades has caused an expansion of eutrophication and loss of water quality for human consumption. The increase of frequency and intensity of cyanobacteria blooms have been recognized as a major problem connected to water quality and eutrophication. The knowledge of environmental factors controlling these blooms is a key step towards the management for recovering aquatic ecosystems from eutrophic conditions. Primary productivity in aquatic ecosystems is dependent on light and nutrients availability. In the present work we evaluated the relative importance of the concentration of major nutrients, such as phosphorus and nitrogen, and light for phytoplankton growth in the main water reservoir of Rio Grande do Norte State, named Engenheiro Armando Ribeiro Gon?alves (EARG), which is an eutrophic system, dominated by potentially toxic cyanobacteria populations. Limitation of phytoplankton growth was evaluated through bioassays using differential enrichment of nutrients (N and/or P) under two light conditions (low light and high light) and monthly monitoring of chlorophyll-a and nutrients (total nitrogen and phosphorus) concentrations, and water transparency (Secchi depth) at the pelagic region. Our results confirm that EARG reservoir is an eutrophic system with a low water quality. Results of bioassays on the growth of phytoplankton limitation (N or P) were conflicting with the results predicted by the TN:TP ratios, which indicates that these ratios were not a good indicator of algal growth limitation. Nitrogen was the limiting nutrient, considering both frequency and magnitude. Light and hidrology affected phytoplankton response to nutrient enrichment. The extreme eutrophic conditions of this reservoir, dominated by cyanobacteria blooms, demand urgent managing strategies in order to guarantee the multiple uses for this system, including water supply for human population. Although nitrogen is the limiting nutrient, an effective management program must focus on the reduction of both phosphorus and nitrogen input / O aumento da polui??o nos ecossistemas aqu?ticos nas ultimas d?cadas tem causado uma expans?o da eutrofiza??o e perda da qualidade da ?gua para o consumo humano. O aumento da freq??ncia e intensidade de flora??es de cianobact?rias tem sido reconhecido com o principal problema ligado a eutrofiza??o e qualidade da ?gua. O conhecimento dos fatores ambientais que controlam essas flora??es ? um passo fundamental para a gest?o de recupera??o de ecossistemas aqu?ticos eutrofizados. A produtividade em ecossistemas aqu?ticos ? dependente da disponibilidade de luz e nutrientes. No presente trabalho, n?s avaliamos a import?ncia relativa da concentra??o dos principais nutrientes (nitrog?nio e f?sforo) e da luz para o crescimento fitoplanct?nico no principal reservat?rio do estado do Rio Grande do Norte, o reservat?rio Engenheiro Armando Ribeiro Gon?alves (EARG), que ? um sistema eutrofizado, dominado por cianobact?rias potencialmente t?xicas. A limita??o do crescimento fitoplanct?nico foi avaliada atrav?s de bioensaios usando enriquecimento diferencial de nutrientes (N e/ou P) sob duas condi??es de luz (baixa e alta luz) e monitoramento mensal das concentra??es de nutrientes (nitrog?nio e f?sforo totais), clorofila a e transpar?ncia da ?gua (profundidade de Secchi) na regi?o pel?gica. Nossos resultados confirmaram que o reservat?rio EARG ? um sistema eutr?fico com baixa qualidade da ?gua. Os resultados dos bioensaios sobre a limita??o do crescimento fitoplanct?nico foram contradit?rios com os resultados preditos pelas raz?es NT:PT, o que indica que essas raz?es n?o s?o um bom indicador da limita??o do crescimento. O nitrog?nio foi o nutriente limitante, tanto em freq??ncia quanto em magnitude. A luz e o regime hidrol?gico afetaram a resposta do fitopl?ncton ao enriquecimento com nutrientes. As condi??es eutr?ficas deste reservat?rio, dominado por flora??es de cianobact?rias, demanda estrat?gias de manejo a fim de garantir os usos m?ltiplos neste sistema, incluindo o abastecimento de ?gua para o consumo humano. Embora o nitrog?nio seja o nutriente limitante, um programa de manejo efetivo dever? focar sobre a redu??o da entrada de f?sforo e nitrog?nio
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Paisagem arquitet?nica da cidade de Jo?o Pessoa/PB e seu significado: o perceptivo dos moradores e visitantesBandeira, S?mia ?rika Alves de Caldas 28 February 2011 (has links)
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Previous issue date: 2011-02-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study was conducted in the city of Jo?o Pessoa, Para?ba mesoregion Forest. Having to analyze how does the appreciation of the architectural heritage to the visitor and pessoense Capital Paraiba, taking into account the narratives of Jo?o Pessoa, and practitioners of foreign tourists of cultural tourism. This research builds on a theoretical foundation on concepts of landscape and place. Was taken as a foundation to Cultural Geography. The
research in question is justified by embarking on Geography and Heritage and cast a glance on the geographical cultural landscape, trying to unravel the symbols assigned to the ancient architectural examples, meaning that interfere with power relationships that cross generations, constructing and deconstructing identities, is dispersed or integrating cultures, creating cultural groups and social conflict. It is concluded that the geographical area derives from a number of factors, among them the culture and this in turn will shaping the landscape, reflecting the abstract over the concrete architecture of the oldest to the most current, turning from the material to the immaterial in World Heritage Site / O presente estudo foi realizado no munic?pio de Jo?o Pessoa, na Mesorregi?o da Mata paraibana. Tendo como objetivo analisar como se d? a valoriza??o do cultural arquitet?nico para o pessoense e para o visitante da Capital paraibana, levando em considera??o as narrativas dos pessoenses, e dos turistas estrangeiros praticantes do turismo cultural. Esta pesquisa ap?ia-se numa fundamenta??o te?rica pautada nos conceitos de paisagem e lugar. Tomou-se como alicerce a Geografia Cultural. A investiga??o em pauta justifica-se por enveredar na Geografia e Patrim?nio e lan?ar um olhar geogr?fico sobre a paisagem cultural, tentando desvendar s?mbolos atribu?dos aos exemplares arquitet?nicos antigos, significados que interferem nas rela??es de poder que atravessam gera??es, construindo e desconstruindo identidades, seja dispersando ou integrando culturas, gerando grupos culturais e conflitos sociais. Conclui-se que o espa?o geogr?fico deriva de um conjunto de fatores dentre eles a cultura e esta por sua vez vai modelando a paisagem, refletindo o abstrato sobre o concreto das arquiteturas mais antigas at? as mais atuais, transformando desde o material at? o imaterial em Patrim?nio da Humanidade
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Transportadores s?lidos de oxig?nio ? base de n?quel e cobre suportados em aluminatos para combust?o do metano pela tecnologia de recircula??o qu?micaPeres, Ana Paula da Silva 08 September 2014 (has links)
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Previous issue date: 2014-09-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Nos ?ltimos anos, transportadores s?lidos de oxig?nio adequados t?m sido
desenvolvidos para serem utilizados em diferentes processos de Recircula??o Qu?mica.
O sucesso desta tecnologia est? diretamente relacionado com a reatividade qu?mica e a
capacidade de armazenamento de oxig?nio do transportador. Desta forma, a pesquisa no
desenvolvimento de novos materiais que possam ser aplicados ao processo torna-se de
fundamental import?ncia. Entre os poss?veis candidatos est?o os transportadores
baseados em n?quel e cobre por apresentarem propriedades termodin?micas favor?veis.
Neste trabalho, aluminatos do tipo MAl2O4 (M=Mg e Ca) e M0,9B0,1Al2O4 (B=Ni e Cu)
usados como suportes, foram sintetizados pela rea??o de combust?o assistida por microondas
e calcinados a 900?C/2h. Em seguida, os suportes foram impregnados com 10%
(m/m) de n?quel ou cobre e, posteriormente calcinados a 600?C/2h para obten??o dos
transportadores s?lidos de oxig?nio, que foram caracterizados por Difra??o de raios X
(DRX), Microscopia eletr?nica de varredura (MEV) e Redu??o a temperatura
programada (RTP). Rea??es simulando o processo de combust?o por recircula??o
qu?mica foram realizados atrav?s de ciclos de redu??o/oxida??o, com o objetivo de
avaliar a reatividade dos transportadores. A an?lise de DRX mostrou picos de difra??o
de estruturas tipo espin?lio. Nos suportes dopados n?o foram verificadas a presen?a de
fases secund?rias, sugerindo que todo o metal foi incorporado ? estrutura do espin?lio.
Nos transportadores s?lidos de oxig?nio, as fases NiO e CuO foram observadas ap?s a
impregna??o das fases ativas sobre os diferentes suportes. Os resultados das avalia??es
dos ciclos qu?micos de redu??o/oxida??o revelaram que os TSO?s impregnados com
n?quel em diferentes suportes mostraram-se mais ativos, sendo potenciais candidatos
para a aplica??o na tecnologia de Recircula??o Qu?mica. / In recent years, solid carriers suitable oxygen have been developed for use in different
chemical processes recirculation. The success of this technology is directly related to
the chemical reactivity and the oxygen storage capacity of the carrier. Thus, research
into the development of new materials that can be applied to the process becomes
extremely important. Possible candidates are the carriers based on nickel and copper for
presenting favorable thermodynamic properties. In this work, aluminates type MAl2O4
(M = Mg and Ca) and M0,9B0,1Al2O4 (B = Ni and Cu) that are used as supports were
synthesized by combustion reactions assisted by microwave and calcined at 900?C/2h.
Then, the carriers were impregnated with 10% (m/m) of nickel or copper, and
subsequently calcined at 600?C/2h to obtain the solid oxygen carriers, which were
characterized by X-ray diffraction (XRD) Microscopy scanning electron microscopy
(SEM) and temperature programmed reduction (TPR). Reactions simulating the
combustion process by chemical recirculation were performed by cycles
reduction/oxidation, in order to evaluate the reactivity of carriers. XRD analysis
revealed diffraction peaks of the spinel type structures. In the doped substrates were
verified the presence of secondary phases, suggesting that all the metal was
incorporated into the spinel structure. In solid oxygen carriers, the NiO and CuO phases
were observed after impregnation of active phases on different media. The results of
evaluations of chemical cycles reduction/oxidation revealed that TSO's impregnated
with nickel in various media were more active and are potential candidates for use in the
chemical recirculation technology
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Um retrato do marginal brasileiro mediante o trabalho do ator com as personagens de Pl?nio Marcos em ?Navalha na carne"Nino, Berttony da Silva 13 March 2015 (has links)
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Previous issue date: 2015-03-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Esta disserta??o apresentada tem como objeto de investiga??o o trabalho do ator na
constru??o das a??es f?sicas, conforme a metodologia desenvolvida por Constantin
Stanislavski em sua an?lise da a??o dram?tica, denominada ?m?todo da a??o f?sica?,
aplicada ?s quest?es da representa??o c?nica do marginal brasileiro, segundo o olhar
?cruel? e realista/naturalista do dramaturgo Pl?nio Marcos. Partindo das circunst?ncias
dadas pelo universo Pliniano, a inten??o ? contribuir para a reflex?o sobre o trabalho do
ator na cena com as personagens marginais de ?Navalha na carne?, destacando alguns
aspectos importantes, que auxiliem na constru??o deste mundo ficcional. Deseja-se criar
condi??es para a forma??o de um ator que potencialize na cena as contradi??es e
conflitos desta obra. A investiga??o pretende partir do estudo te?rico-pr?tico como
hip?tese metodol?gica, produzindo reflex?o cr?tica a partir do processo criativo do ator
com a realiza??o de um experimento c?nico centrado na t?cnica psicof?sica deste
pedagogo russo. Assim, pretende-se lan?ar um olhar sobre o ?m?todo das a??es f?sicas?
com foco na sua ?ltima grande contribui??o para a atua??o, notadamente o
procedimento da an?lise ativa, ao fazer uma leitura a partir de ?Navalha na carne? por
meio deste exerc?cio c?nico criativo, ampliando os estudos que se ocupam da arte do
ator. Esta pesquisa faz uma explana??o geral sobre a trajet?ria de Stanislavski at? seu
encontro com a a??o f?sica, ao mesmo tempo que, destaca os desencontros de
entendimento do seu trabalho pelo mundo. Stanislavski desenvolveu inicialmente o
?m?todo? tendo como pano de fundo, a est?tica realista - uma rela??o de di?logo entre
realidade e a cena ? atrav?s de uma estiliza??o que cria uma realidade teatral, e
consequentemente, art?stica, e n?o de forma literalmente naturalista atrav?s de um
mimetismo integral. Ou seja, o trabalho de representa??o na est?tica realista do teatro
deve ser elaborado a fim de criar uma realidade teatralizada. Stanislavski entende que
teatro ? conven??o, j? que o trabalho do ator sobre si pr?prio deve estimular essa
segunda natureza, a c?nica. / This thesis presented is to research the actor's work in the construction of physical
actions, according to the methodology developed by Constantin Stanislavski in his
analysis of dramatic action, called "method of physical action", applied to questions of
scenic representation of the Brazilian marginal, according to the look "cruel" and
realistic / naturalistic Plinio Marcos playwright. Based on the circumstances given by
Pliniano universe, the intention is to contribute to the reflection on the actor's work on
the scene with the marginal characters in "Razor in the Flesh", highlighting some
important aspects, to assist in the construction of this fictional world. You want to
create conditions for the formation of an actor that leverages the scene the
contradictions and conflicts of this work. The research aims from the theoretical and
practical study as a methodological hypothesis, producing critical reflection from the
creative process of the agent with the realization of a scenic experiment focused on
psychophysical technique of this Russian pedagogue. Thus, we intend to have a look at
the method of physical actions focusing on his last great contribution to the work,
especially the procedure of active analysis by doing a reading from "Razor in the Flesh"
through this creative scenic exercise, extending the studies concerning the actor's art.
This research is a general explanation about the trajectory of Stanislavski to his
encounter with the physical action, while, highlights the inconsistencies of
understanding of his work around the world. Stanislavski initially developed the
"method" having as a backdrop, the realist aesthetic - a dialogue relationship between
reality and the scene - through a style which creates a theatrical reality, and
consequently, artistic, not literally naturalistic way through an integral mimicry. That is,
the representation of work in realistic theater aesthetics should be developed in order to
create a theatrical reality. Stanislavski believes that theater is convention, since the
actor's work on himself should encourage this second nature, scenic.
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Comp?sitos NiO-CGO obtidos pelo m?todo de s?ntese em uma etapaGrilo, Jo?o Paulo de Freitas 25 June 2015 (has links)
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Previous issue date: 2015-06-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Comp?sitos NiO-C0.9Gd0.1O1.95 (NiO-CGO), um dos materiais mais utilizado para
fabrica??o de anodos de C?lulas a Combust?veis de ?xido S?lido (CCOS) atualmente,
foram obtidos por uma rota qu?mica que consiste na mistura das solu??es precursoras
das fases NiO e CGO previamente obtidas pelo m?todo Pechini, com percentual
m?ssico da fase NiO variando entre 0 e 100 %. Os nanop?s como obtidos foram
caracterizados por t?cnicas de an?lise t?rmica (termogravimetria e Calorimetria
Diferencial Explorat?ria) e os materiais calcinados foram estudados por difratometria de
raios X (DRX). Amostras sinterizadas entre 1400 e 1500 ?C por 4 h foram
caracterizadas pelo m?todo de Arquimedes. Os efeitos da composi??o relativa na
microestrutura e propriedades el?tricas (condutividade e energia de ativa??o) de
comp?sitos sinterizados a 1500 ?C foram investigados por microscopia eletr?nica e
espectroscopia de imped?ncia (entre 300 e 650 ?C em ar). O refinamento dos dados de
DRX indicaram que os p?s s?o ultrafinos e que o tamanho do cristalito da fase CGO
tende a diminuir com o aumento de teor de NiO. De maneira semelhante, o cristalito da
fase NiO tende a diminuir com o aumento da concentra??o de CGO, principalmente
acima de 50% em massa de CGO. A an?lise por Arquimedes evidencia uma varia??o na
densidade relativa em fun??o do teor de NiO. Densidades relativas acima de 95% foram
obtidas em comp?sitos contendo a partir de 50 % em massa de NiO e sinterizados entre
1450 e 1500 ?C. Os resultados de microscopia e espectroscopia de imped?ncia indicam
que a partir de 30 - 40 % de NiO h? aumento do n?mero de contatos NiO-NiO, ativando
o mecanismo de condu??o eletr?nica que governa o processo de condu??o a baixas
temperaturas (300-500 ?C). Por outro lado, com o aumento da temperatura de medida a
mobilidade das vac?ncias de oxig?nio torna-se maior que a dos buracos eletr?nicos do
NiO, como resultado, a condutividade de alta temperatura (550 - 650 ?C) em
comp?sitos contendo at? 30-40% de NiO ? inferior ? do CGO. Varia??es na energia de
ativa??o confirmam mudan?a do mecanismo de condu??o com o aumento do teor de
NiO. O comp?sito contendo 50 % em massa de cada fase apresenta condutividade de 19
mS/cm a 650 ?C (pouco superior a 13 mS/cm encontrada para o CGO) e energia de
ativa??o 0,49 eV. / Composite NiO-C0.9Gd0.1O1.95 (NiO-GDC), one of the materials most used for the
manufacture of anodes of Cells Solid Oxide Fuel (SOFC) currently, were obtained by a
chemical route which consists in mixing the precursor solution of NiO and CGO phases
obtained previously by the Pechini method. The nanopowders as-obtained were
characterized by thermal analysis techniques (thermogravimetry and Differential
Scanning Calorimetry) and calcined materials were evaluated by X-ray diffraction
(XRD). Samples sintered between 1400 and 1500 ? C for 4 h were characterized by
Archimedes method. The effects of the composition on the microstructure and electrical
properties (conductivity and activation energy) of the composites sintered at 1500 ? C
were investigated by electron microscopy and impedance spectroscopy (between 300
and 650 ? C in air). The refinement of the XRD data indicated that the powders are
ultrafine and the crystallite size of the CGO phase decreases with increasing content of
NiO. Similarly, the crystallite of the NiO phase tends to decrease with increasing
concentration of CGO, especially above 50 wt % CGO. Analysis by Archimedes shows
a variation in relative density due to the NiO content. Densities above 95% were
obtained in samples containing from 50 wt % NiO and sintered between 1450 and 1500
?C. The results of microscopy and impedance spectroscopy indicate that from 30-40
wt.% NiO there is an increase in the number of contacts NiO - NiO, activating the
electronic conduction mechanism which governs the process of conducting at low
temperatures (300 - 500 ?C). On the other hand, with increasing the measuring
temperature the mobility of oxygen vacancies becomes larger than that of the electronic
holes of NiO, as a result, the high temperature conductivity (500-650 ? C) in composites
containing up to 30-40 wt.% of NiO is lower than that of CGO. Variations in activation
energy confirm change of conduction mechanism with the increase of the NiO content.
The composite containing 50 wt. % of each phase shows conductivity of 19 mS/cm at
650 ?C (slightly higher than 13 mS/cm found for CGO) and activation energy of 0.49
eV.
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Nanorevestindo fibras de PET com TiO2 dopado com metal de transi??o para aplica??o autolimpanteFelipe, Brenno Henrique Silva 19 February 2015 (has links)
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Previous issue date: 2015-02-19 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / O presente projeto visa a s?ntese e caracteriza??o de um nanorevestimento de di?xido de tit?nio dopado com prata em tecido de poli?ster arom?tico, a fim de desenvolver um material t?xtil funcional com aplica??oself-cleaning. Uma t?cnica de deposi??o f?sica de vapor (PVD) foi utilizada como m?todo de s?ntese. A sele??o do material suporte e a t?cnica utilizada na obten??o dos nanorevestimentos s?o vari?veis que podem influenciar nas suas propriedades funcionais, homogeneidade e ades?o. As fibras t?xteis s?o materiais muito empregados como substrato por possu?rem uma maior flexibilidade, serem facilmente adapt?veis a qualquer geometria e baixo custo. A presen?a de Ag e TiO2, bem como sua cristalinidade, foi comprovada atrav?s das an?lises de difra??o de raios X (DRX), espectroscopia fotoeletr?nica de raios-X (XPS) e fluoresc?ncia de raios-x (FRX). A morfologia de superf?cie foi avaliada atrav?s das t?cnicas de microscopia de for?a at?mica (AFM) e microscopia eletr?nica de varredura (MEV). A efici?ncia da atividade fotocatal?tica do material foi comprovada pela descolora??o do corante acid blue 113 em meio a fontes de radia??o UV, com uso da t?cnica de espectroscopia de absor??o (96%). A degrada??o da mol?cula do corante acid blue 113 foi confirmada atrav?s da t?cnica de espectroscopia de infravermelho por transformada de Fourier (FTIR). O car?ter hidrof?bico do nanorevestimento foi confirmado atrav?s da t?cnica de medida de ?ngulo de contato. O car?ter anti UV foi confirmado foi confirmado de acordo com a metodologia normativa AS/NZS 4399:1996. Os resultados comprovam que o material desenvolvido apresenta uma alta capacidade autolimpante, bem como protetora UV. / Innovative methods in the textile segment is currently responsible for increase in production processes, development of new materials and add new technologies in an area that was one of the major participants in the industry revolution. Thus, much research has been responsible for putting the textile industry in the new era of technological revolution watching so, the dynamism of microelectronics companies, food, and mechanics, among others. To this end, this PhD project aims to add value research involving new textile materials. Thus, this project aims to make the synthesis and characterization of a silver doped titanium dioxide nanocoating on polyester fabric in order to develop a functional textile material with self-cleaning application. A physical vapor deposition technique (PVD) was used as the method of synthesis. The selection of the support material and the technique used in obtaining the nanocoatings are variables that can influence their functional properties, uniformity and adhesion. The textile fibers are materials used as substrate by having greater flexibility to be easily adaptable to any geometry and low cost. The efficiency of the photocatalytic activity of the material was confirmed by discoloration of the dye Acid Blue 113 through UV radiation sources, using absorption spectroscopy (96%). The presence of Ag and TiO2 was confirmed by analysis of X-ray diffraction (XRD) photoelectron spectroscopy X-ray (XPS) and x-ray fluorescence (XRF). The surface morphology was evaluated through the techniques of atomic force microscopy (AFM) and scanning electron microscopy (SEM). Degradation of Acid Blue 113 dye molecule was confirmed by infrared spectroscopy Fourier transform (FTIR). The hydrophobic character of nanocoating was confirmed by contact angle measurement technique. The results show that the developed material has a high capacity self-cleaning pro perties
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Conte?dos de matem?tica do ensino m?dio com abordagem de racioc?nio recursivo e quest?es do ENEM e OBMEPSantiago, Ana Patr?cia Moreira 27 August 2015 (has links)
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Previous issue date: 2015-08-27 / Neste trabalho,temos a ?nalidade de relembrar o professor de matem?tica do Ensino M?dio o processo recursivo para que o mesmo possa utilizar essa ferramenta ao introduzir conte?dos usando recursao, como uma alternativa para o ensino de matem?tica. Para tanto, foi feito uso de quest?es oriundas do Exame Nacional do Ensino M?dio (ENEM) e a Olimp?ada Brasileira de Matem?tica das Escolas P?blicas (OBMEP), al?m de apresentarmos alguns conte?dos de matem?tica que s?o de?nidos por recurs?o. Nesta disserta??o, mostramos tamb?m algumas atividades que envolvem o racioc?nio recursivo e foram aplicadas em uma turma de 3? ano do ensino m?dio de uma escola estadual de Natal/RN. / In this work, we have the purpose of reminding the math teacher of High School the recursive process
so that he/she can use this tool to introduce contents, using recursion as an alternative to the teaching of
mathematics. For this, we used questions taken from the Exame Nacional do Ensino M?edio (ENEM)
[National Examination of High School] and from the Olimp??ada Brasileira de Matem?atica das Escolas
P?ublicas (OBMEP) [Brazilian Mathematics Olympiad of Public Schools], in addition to present some
contents of mathematics that are defined by recursion. In this dissertation, we also showed some
activities that involved the recursive reasoning and were applied in a 3rd grade class of high school in
a public school in Natal / RN.
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O registro de procedimentos metodol?gicos em projetos de interven??o arquitet?nica no patrim?nio edificado: o caso de Natal-RNOlimpio, Monique Lessa Vieira 12 June 2015 (has links)
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Previous issue date: 2015-06-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / de intervir sobre o patrim?nio edificado, observa-se a prolifera??o de in?meras posturas
projetuais frente ? pr?-exist?ncia de valor patrimonial. Mas estes projetos de interven??o em
edifica??es de reconhecido valor patrimonial possuem alguma especificidade? ? poss?vel
identificar em que eles diferem (ou se diferem) de um projeto arquitet?nico n?o relacionado ?s
quest?es preservacionistas? Diante de in?meras contribui??es te?ricas sobre a tem?tica de
m?todos de projeta??o arquitet?nica, identificou-se uma escassez de estudos voltados,
especificamente, para projetos de interven??o em ?reas ou edifica??es de reconhecido valor
patrimonial. Evidenciou-se, ent?o, a necessidade de uma reflex?o sobre os procedimentos
metodol?gicos aplicados em um projeto de arquitetura, notadamente os voltados para a
preserva??o patrimonial. Esta discuss?o se reveste de uma import?ncia ainda maior, pois, em
?mbito nacional, algumas das recentes reflex?es sobre esse tipo de projeto apontam para uma
atua??o caracterizada, muitas vezes, pelo arb?trio e completa aus?ncia de rigor metodol?gico.
Logo, esta pesquisa trabalhou de forma conexa elementos te?rico-metodol?gicos da pr?tica
preservacionista e da tem?tica sobre m?todos de projeta??o arquitet?nica. Visando responder
as quest?es apresentadas, o recorte desta an?lise consiste no estudo de caso dos projetos de
interven??o do Terminal Mar?timo de Passageiros de Natal, do Antigo Pal?cio do Governo
(EDTAM) e do Antigo Hotel Central, situados na ?rea reconhecida como centro hist?rico da
cidade de Natal, no pol?gono de tombamento federal. Suas an?lises objetivam identificar os
procedimentos metodol?gicos registrados no produto final (representa??o gr?fica do projeto
arquitet?nico e demais documentos) entregue ao IPHAN/RN, ?rg?o respons?vel pela aprova??o
dos mesmos, checando se tais procedimentos refletem no resultado obtido e se compreendem a
complexidade das quest?es preservacionistas. As an?lises dos projetos corroboraram a hip?tese
da exist?ncia de especificidades no projeto de interven??o, diferindo do projeto do novo. A
principal delas refere-se ? pr?pria natureza do projeto, inerente ? rela??o dial?tica entre a
necessidade da preserva??o (dos valores patrimoniais identificados) e da moderniza??o
(adapta??o ? vida contempor?nea) dos bens patrimoniais. Esta rela??o, denominada nesta
disserta??o de ?restri??o radical?, deve (ou deveria) balizar as a??es projetuais e an?lises
t?cnicas do ?rg?o preservacionista. Entretanto, constatou-se que esta restri??o ficou mais clara
nos pareceres dos legisladores do que nas decis?es dos projetistas. Os legisladores estabelecem
a apresenta??o de documentos voltados para a identifica??o e contextualiza??o pr?via do im?vel
objeto de interven??o (Portaria N? 420, de 22 de dezembro de 2010), que oferecem (deveriam)
subs?dios para as decis?es projetuais. Contudo, foi poss?vel identificar na avalia??o dos
documentos uma desconex?o entre estes e as decis?es projetuais apresentadas. A justificativa
para isto ? a total aus?ncia de di?logo sobre os preceitos te?rico-metodol?gicos
preservacionistas, a nosso ver, parte preponderante dos procedimentos necess?rios ao processo
de projeta??o arquitet?nica de interven??o, devendo nortear as discuss?es projetuais entre
projetistas e legisladores. / In the midst of growing preservationist awareness, regarding methods of architectural
intervention of buildings with a recognized heritage value, there are numerous approaches on
how the original heritage value can be protected. However, can these intervention projects be
differentiated? Is it possible to identify how they differ (if in fact they do) from an architectural
project not related to preservation? Although there are numerous theoretical studies regarding
methods utilized in architectonical projects, there appear to be a lack of studies focused on an
architectural intervention exclusively focused on areas or edifications that have a recognized
heritage value, thereby requiring a reflection on which methodological procedures in an
architectonical project serve the purpose of the preservation of the historical aspects. This
discussion is of even greater importance because, at the national level, some recent discussions
on this type of architectural design seem arbitrary and lack methodological rigor. Therefore,
this research attempts to focus equally on the theoretical-methodological practices of
preservation as well as the architectural project methods. In an attempt to address these aspects,
the focus of this research centers on the case studies of the intervention projects of the maritime
passenger terminal of Natal (Terminal Mar?timo de Passageriros de Natal), the old government
hall (Palacio do Governo - EDTAM) and the old central hotel (Hotel Central) which are situated
in the area known as the historic downtown of the city of Natal, within the federal heritage
protection polygon. The analyses of these is intended to identify what methodological
procedures were recorded in the final product (in the graphical representation of the
architectural design and other documents) delivered to IPHAN / RN, the body responsible for
review and approval of these architectural projects, noting whether such procedures appear, in
some way, in the final product, and if an understanding of the complexity of preservation is
evident. The analyses of these projects corroborate the hypothesis that there are unique
characteristics, which must be addressed in the intervention project for preservation when
compared to new project design. The main characteristic to be addressed is related to the very
nature of the project. It is inherent in the dialectical relationship between the need to preserve
(the identified heritage values) and the need to modernize (making adaptations to contemporary
life). This relationship, denominated in this dissertation as "radical restraint", must, or at least
should, guide the actions in the project as well as the technical analyses of the preservationist
organization. However, this radical restriction appears more evident in the guidelines put forth
by legislators than in the decisions of designers. These legislators require the presentation of
documents, aimed at identifying and contextualizing intervention (Ordinance No. 420 of
December 22, 2010), that grant (or should grant) assistance in the decision making process. It
was evident in the analyses of these documents that there existed a disconnect between the
documents produced and the decisions made in the project. This fact can be seen in the total
absence of dialogue about theoretical-methodological preservationist principles, which, in our
view, is an essential element of the methodological procedures of the intervention project
needed to guide the legislative and project design discussions.
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Efeito da adi??o de WC e Co na sinteriza??o e propriedades mec?nicas da aluminaAzevedo, Heytor Vitor Souza Bezerra de 29 January 2016 (has links)
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Previous issue date: 2016-01-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Comp?sitos ? base de alumina (Al2O3), carbeto de tungst?nio (WC) e cobalto (Co) apresentam propriedades espec?ficas como baixa densidade, alta resist?ncia ? oxida??o, alto ponto de fus?o e elevada in?rcia qu?mica. Esse comp?sito revela ser um material promissor para ser aplicado em diversos campos da engenharia. Este trabalho tem como objetivo avaliar algumas propriedades mec?nicas durante a confec??o e, ap?s a sinteriza??o do comp?sito (Al2O3 - WC - Co). P?s comp?sitos com a composi??o de 80%.p de Al2O3, 18%.p de WC e 2%.p de Co foram processados pela rota de moagem de alta energia (MAE), em moinho planet?rio por 50 horas, bem como por mistura manual em um recipiente de vidro, seguindo a mesma propor??o em peso. Amostras foram coletadas (2, 10, 20, 30, 40 e 50 horas) durante o processo de moagem. Em seguida, os p?s foram prensados no formato de amostra circular com di?metro de 5 mm em uma prensa uniaxial com press?es de 200 e 400 MPa. A sinteriza??o ocorreu de duas maneiras: a primeira sinteriza??o via fase s?lida foi realizada ? 1300 ?C e ? 1126 ?C durante 1h com taxa de aquecimento de 10?C/min em forno resistivo sob atmosfera de arg?nio as press?es de compacta??o utilizadas foram de 200 e 400 MPa, a segunda sinteriza??o foi realizada em dilat?metro via fase s?lida ? 1300 ?C com press?o de compacta??o de 200 MPa, tamb?m foi realizada em dilat?metro outra sinteriza??o, desta vez por fase l?quida ? 1550 ?C com press?es de compacta??o de 200 e 400 MPa, obedecendo os mesmos par?metros utilizados no forno resistivo. As mat?rias-primas foram caracterizadas por difra??o de raios X - (DRX), fluoresc?ncia de raios X - (FRX), microscopia eletr?nica de varredura (MEV), espectroscopia por dispers?o de energia (EDS) e particulometria a laser. As amostras sinterizadas foram submetidas a ensaios de microdureza. Os resultados mostraram que a moagem de alta energia atingiu os objetivos quanto ao tamanho de part?cula e a densifica??o do comp?sito. Entretanto, a microdureza n?o alcan?ou resultados significativos, isso ? um ind?cio que o comp?sito possui baixa tenacidade ? fratura. / Composites based on alumina (Al2O3), tungsten carbide (WC) and cobalt (Co) exhibit specific properties such as low density, high oxidation resistance, high melting point and high chemical inertia. That composite shows to be a promising material for application in various fields of engineering. In this work, the mechanical properties of the composite (Al2O3 ? WC ? Co), particularly density and hardness, were evaluated according to the effects of the variables of powder processing parameters, green compact and sintered. Powder composites with the composition of 80 wt% Al2O3, 18 wt% WC and 2 wt% Co were processed by high energy ball milling in a planetary mill for 50 hours as well as mixed by manual mixing in a glass vessel with the same proportion. Samples were collected (2, 10, 20, 30, 40 and 50 hours) during the milling process. Then, the powders were compacted in a cylindrical die with 5 mm in diameter in a uniaxial press with pressures of 200 and 400 MPa. The sintering was in two stages: first, the solid phase sintering was performed at 1126 and 1300 ?C for 1 hour with a heating rate of 10 ?C/min in a resistive furnace under argon atmosphere for green samples compacted in 200 and 400 MPa; the second sintering was performed on dilatometer in solid phase at 1300 ?C for green sample compacted in 200 MPa, another sintering also was performed on dilatometer, this time in liquid phase at 1550 ?C for green samples compacted in 200 and 400 MPa, with the same parameters used in resistive furnace. The raw materials were characterized by X ? ray diffraction (XRD), X ? ray fluorescence (XRF), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and laser particlemeter. The sintered samples were subjected to microhardness testing. The results showed that high energy milling achieved to the objectives regarding the particle size and the dispersion of composite phases. However, the hardness did not achieve to significant results, this is an indication that the composite has low fracture toughness.
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