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Immunomodulation during human pregnancy : placental exosomes as vehicles of immune suppression.Stenqvist, Ann-Christin January 2014 (has links)
The mammalian pregnancy comprises a challenge to the maternal immune system since the fetus is semi-allogeneic and could thus be rejected. Pregnancy success is associated with the placenta that is not only essential for oxygen supply, nourishment and pregnancy hormones but also plays a role in the protection of the fetus against maternal immunologic attack. The aim of the current studies was to elucidate the role of human placenta as an immunomodulatory organ with a special focus on placental exosomes as vehicles for establishment of maternal tolerance to the fetus. We discovered that the syncytiotrophoblast in human normal pregnancy constitutively produces and secretes exosomes. Exosomes are 30-100 nanometer-sized membrane vesicles of endosomal origin that convey intercellular communication. Exosomes are produced and released through the endosomal compartment and reflect the type and the activation state of the cells that produce and secrete them. They carry cytosolic and membrane-bound proteins and nucleic acids and can influence and re-program recipient cells. Depending on their interactions with cells of the immune system they can be divided into immunostimulatory or immunosuppressive. We developed methods for isolation and culture of trophoblast and placental explants from human normal first trimester pregnancy and isolated exosomes from the culture supernatants. These exosomes were characterized biochemically and functionally regarding mechanisms with potential importance in the establishment of maternal tolerance towards the fetus. The following aspects were studied: 1) exosomal modulation of the NKG2D receptor-ligand system, a major cytotoxic pathway for NK- and cytotoxic T cells and thus potentially dangerous to the fetus; 2) placental exosome-mediated apoptosis of activated immune effector cells; and 3) Foxp3-expressing T regulatory cells in human pregnant uterine mucosa, the decidua. Using immuno electron microscopy we show that human early syncytiotrophoblast constitutively expresses the stress-inducible NKG2D ligands MICA/B and ULBP1-5, and the apoptosis inducing molecules FasL and TRAIL. While MICA/B were expressed both on the cell surface and intracellularly on the limiting membrane of multivesicular bodies (MVB) and on exosomes, the ULBP1-5, FasL and TRAIL were solely processed through the MVB of the endosomal compartment and secreted on exosomes. The NKG2D ligand-expressing placental exosomes were able to internalize the cognate receptor from the cell surface of activated NK- and T cells thus down regulating their cytotoxic function. In our studies of apoptosis we found that placental exosomes carry the proapoptotic ligands FasL and TRAIL in their active form as a hexameric complex of two homotrimeric molecules, required for triggering of the apoptotic signaling pathways. This finding was supported by the ability of isolated placental FasL/TRAIL expressing exosomes to induce apoptosis in activated peripheral blood mononuclear cells (PBMC) and Jurkat T cells. Additionally, we studied Foxp3-expressing T regulatory (Treg) cells in paired human decidual and blood samples from pregnant women compared to non-pregnant controls. The CD4+CD25+Foxp3+ Treg cells were 10 fold enriched in the decidual mucosa compared to peripheral blood of pregnant women and non-pregnant controls. We discovered a pool of Foxp3-expressing, CD4+CD25- cells in human decidua, a phenotype consistent with naïve/precursor Foxp3+ Treg cells. These results suggest local enrichment of Treg cells in decidua of normal pregnancy. Furthermore, we have results indicating that the exosomes, isolated from placental explant cultures, carry PD-L1 and TGFβ on their surface, molecules known to promote induction of Treg cells. Taken together, our results provide evidence that placental exosomes are immunosuppressive and underline their role in the maternal immune modulation during pregnancy. The constitutive production and secretion of immunosuppressive placental exosomes create a protective exosomal gradient in the blood surrounding the feto-placental unit. This “cloud of immunosuppressive exosomes” conveys immunologic privilege to the developing fetus and thus contributes to the solution of the immunological challenge of mammalian pregnancy.
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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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Oxida??o eletroqu?mica para o tratamento da ?gua produzida proveniente da ind?stria petroqu?mica da regi?o Nordeste do BrasilMelo, Jaqueline Ferreira de 16 October 2017 (has links)
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Previous issue date: 2017-10-16 / Diferentes metodologias s?o investigadas para a remo??o dos poluentes presente na ?gua produzida proveniente da explora??o de petr?leo, a fim de diminuir o impacto ambiental. Nos ?ltimos anos uma aten??o especial tem sido dada para as tecnologias eletroqu?micas. Neste trabalho foi empregada a oxida??o eletroqu?mica indireta em dois efluentes reais provenientes da ind?stria do petr?leo situada no Estado do Rio Grande do Norte. Os experimentos foram realizado em sistemas em batelada e fluxo com os eletrodos de ?xido de Rut?nio (Ti/Ru0.3Ti0.7O2), Platina suportada em Tit?nio (Ti/Pt) e Diamante Dopado com Boro (BDD - sigla em ingl?s) e como c?todo o Tit?nio (Ti), aplicando diferente densidades de corrente (15 mA cm-2 e 45 mA cm-2). Para an?lise da adequa??o do tratamento eletroqu?mico foi verificado o decaimento da demanda qu?mica de oxig?nio (DQO), atrav?s de suas concentra??es ao fim do tratamento. De acordo com os resultados obtidos para os sistemas em batelada, a remo??o DQO foi aproximadamente 42% com consumo energ?tico de 115 KWhm-3 e 52% com 86 KWhm-3 consumidos usando BDD e Ti/Pt respectivamente, nessas condi??es o ?nodo de Ti/Ru0.3Ti0.7O2 mostrou a melhor efici?ncia de degrada??o com 85% de remo??o da mat?ria org?nica e menor consumo energ?tico 70 KWhm-3, o comportamento mais eficiente desse eletrodo foi correlacionado a evolu??o das esp?cies oxidativas cloradas (, , ) no ?nodo durante o tratamento. Quando efluentes reais foram submetidos ao tratamento eletroqu?mico em c?lula de fluxo os melhores resultados foram obtidos com o ?nodo de BDD j? na menor densidade de corrente aplicada, com valores de mineraliza??o pr?ximos da totalidade e consumo energ?tico de 66 KWhm-3. A toxicidade dos efluentes tratados foi estimada por meio do cultivo da Lactuca Sativa a fim de avaliar o poss?vel reuso do efluente ap?s tratamento, o qual se mostrou efetivo quando analisado o fator de germina??o para o efluente tratado com ambos os ?nodos em condi??es de fluxo com desenvolvimento do caule mais expressivo se comparado ? amostra de refer?ncia para o ?nodo de Ti/Ru0.3Ti0.7O2. Nos sistemas em batelada a carga org?nica e a produ??o de oxidantes ao final da desinfec??o eletroqu?mica inibiram a germina??o da Lactuca sativa, o qual foi atribu?do aos oxidantes remanescentes no efluente tratado, evitando a germina??o devido ao ataque dos oxidantes das paredes celulares das sementes de alface. Os resultados indicam a efici?ncia do m?todo para remo??o dos compostos org?nicos confirmando a aplicabilidade para os efluentes estudados.
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An?lise da viabilidade econ?mica e ambiental para a cria??o de uma usina de reciclagem de res?duos da constru??o civil em uma abordagem simbi?tica: um estudo para a regi?o metropolitana de Natal / Analysis of economic and environmental viability for the creation of a civil construction waste recycling plant in a symbiotic approach: a estudy for the metropolitan region of NatalPaiva, Izabelle Virg?nia Lopes de 28 July 2016 (has links)
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Previous issue date: 2016-07-28 / O modelo de produ??o observado na ind?stria da constru??o civil utiliza em boa parte recursos naturais n?o renov?veis e ? respons?vel pela gera??o de uma grande quantidade de res?duos. Uma das formas de amenizar os impactos desses res?duos ? a reciclagem. Diante deste cen?rio, o objetivo deste trabalho ? propor a cria??o de uma usina de reciclagem de Res?duos da Constru??o Civil na perspectiva da simbiose industrial, avaliando a sua viabilidade econ?mica e ambiental. A pesquisa ? um Estudo de caso de car?ter explorat?rio, de natureza aplicada, com uma abordagem quanti-qualitativa. Um question?rio estruturado foi aplicado junto ?s empresas da constru??o civil da grande Natal, cadastradas no SINDUSCON-RN, com o objetivo de conhecer a quantidade m?dia de res?duos gerada pelas construtoras, o destino dado aos res?duos e se h? separa??o dos res?duos na obra antes da destina??o. Com isso foi poss?vel estimar o tamanho da usina e seu volume de produ??o, para, assim, dimensionar os impactos ambientais envolvidos e estimar os custos e despesas, fatores essenciais para realiza??o das an?lises de viabilidade. Utilizou-se o Estudo de Impacto Ambiental (EIA) para a avalia??o ambiental e os m?todos de Valor Presente L?quido (VPL), Taxa Interna de Retorno (TIR) e payback para a realiza??o da avalia??o econ?mica. O trabalho concluiu que a implanta??o da usina de reciclagem de res?duos da constru??o civil na regi?o metropolitana de Natal ? vi?vel tanto ambiental quanto economicamente, bem como a organiza??o de forma simbi?tica das empresas ? vista de forma positiva no sentido de incentivar a separa??o dos res?duos na obra e, consequentemente, melhorar a qualidade do agregado reciclado produzido. Al?m disso, o reaproveitamento de res?duos pelas pr?prias construtoras reduz a extra??o de recursos naturais n?o renov?veis e a gera??o de novos res?duos, contribuindo para a diminui??o do impacto ambiental gerado por este setor. / The production model observed in the construction industry uses largely non-renewable natural resources and is responsible for generating a large number of waste. One way to mitigate the impacts of this waste is recycling. In this scenario, the objective of this study is to propose the creation of a construction waste recycling plant from the perspective of industrial symbiosis, assessing their economic and environmental viability. The research is an exploratory case study of applied nature, with a quantitative and qualitative approach. A structured questionnaire was administered with the companies of civil construction of the great Natal registered in SINDUSCON-RN, in order to know the average amount of waste generated by construction companies, the destination of the waste and if there is separation of waste in the work before allocation. Thus, it was possible to estimate the size of the plant and its production volume, to thereby scale the environmental impacts involved and estimate the costs and expenses, essential factors for carrying out feasibility studies. We used the Environmental Impact Assessment (EIA) for environmental assessment and methods of Net Present Value (NPV), Internal Rate of Return (IRR) and payback for the realization of economic evaluation. The study concluded that the implementation of the construction waste recycling plant in the metropolitan region of Natal is viable environment as much as economically, as well as the organization symbiotically of companies is seen in a positive way to encourage the separation of waste at work and, consequently, improve the quality of the recycled aggregate produced. In addition, the reuse of waste by own construction companies reduces the extraction of non-renewable natural resources and the generation of new waste, contributing to the reduction of the environmental impact generated by this sector.
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Fam?lia e depend?ncia qu?mica na contemporaneidade: o lugar da fam?lia na pol?tica sobre drogasRocha, Gleyca Thy?s da Silva Romeiro 31 August 2017 (has links)
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Previous issue date: 2017-08-31 / O presente trabalho tem como proposta analisar a fam?lia e a depend?ncia qu?mica na contemporaneidade, dando ?nfase para a discuss?o do lugar da fam?lia na pol?tica sobre drogas. Aborda a discuss?o sobre o uso e abuso de drogas e a depend?ncia qu?mica (entendida como doen?a) e sua repercuss?o na institui??o familiar no contexto da sociedade brasileira, evidenciando tamb?m as atuais pol?ticas sobre drogas e o percurso de avan?os e retrocessos inseridos na perspectiva da Reforma Sanit?ria. Al?m disso, ? trazido uma discuss?o em torno da fam?lia e suas novas configura??es na contemporaneidade, apresentando o seu lugar frente a doen?a da depend?ncia qu?mica e da pol?tica sobre drogas. Fam?lia esta que entra em processo de adoecimento assim como o dependente qu?mico, desenvolvendo a codepend?ncia. Tem como objetivo geral analisar a fam?lia do indiv?duo acometido pela doen?a da depend?ncia qu?mica no ?mbito das institui??es de sa?de mental no munic?pio de Nata/RN, demarcando o seu lugar na pol?tica de sa?de mental, sua visibilidade, seu protagonismo e os seus desafios. Os objetivos espec?ficos tratam de: Analisar os determinantes s?cio-hist?ricos que incidem na configura??o das pol?ticas p?blicas na ?rea da sa?de mental, demarcando a forma como estas v?m respondendo a crescente demanda da doen?a da depend?ncia qu?mica e o lugar da fam?lia na agenda dessas pol?ticas; analisar as a??es desenvolvidas nas institui??es voltadas ao tratamento da depend?ncia qu?mica, tendo presente o v?nculo ou n?o dessas institui??es ? proposta da Reforma Psiquiatra e Luta Antimanicomial; identificar como ocorre (e se ocorre) a aten??o ?s fam?lias (codependentes) durante o processo de tratamento do usu?rio de subst?ncias psicoativas (SPA) - dependente qu?mico; analisar os aspectos que denotam a visibilidade, o protagonismo e os desafios dos familiares no processo de tratamento, na condi??o de codependentes. O trabalho articula em seu percurso metodol?gico uma pesquisa bibliogr?fica, associadas a uma pesquisa de campo, em que foi aplicada entrevista semiestruturada com os sujeitos de pesquisa, profissionais das institui??es do universo de pesquisa e familiares que no per?odo da pesquisa de campo estava com algum membro de sua fam?lia em tratamento. No que tange aos resultados obtidos nesta pesquisa, cabe destacar o posicionamento dos sujeitos de pesquisa (profissionais da sa?de e familiares) em rela??o aos atuais servi?os voltados ao tratamento da depend?ncia qu?mica e acompanhamento com a fam?lia, que no ?mbito da pol?tica p?blica de sa?de mental se torna cada vez mais prec?ria. Concluindo, portanto, a necessidade em dar maior visibilidade para a problem?tica da depend?ncia qu?mica e as fr?geis estrat?gias de enfrentamento a esse problema que se configura como uma express?o da quest?o social; necessitando de um olhar diferenciado para todos os atores nele envolvido: usu?rio, fam?lia e sociedade. / The present work aims at analyzing the family and chemical dependency in the contemporary world, emphasizing the discussion of the place of the family in drug policy. It addresses the discussion about drug use and abuse and chemical dependency (understood as disease) and its repercussion in the family institution in the context of Brazilian society, also showing current drug policies and the path of advances and setbacks inserted in the perspective of the Reform Sanitary In addition, a discussion is brought about the family and its new configurations in the contemporary world, presenting its place in the face of the disease of chemical dependence and drug policy. Family is in the process of becoming ill as well as the dependent chemist, developing codependency. It has as general objective to analyze the family of the individual affected by the disease of the chemical dependence within the mental health institutions in the municipality of Nata / RN, demarking its place in the mental health policy, its visibility, its protagonism and its challenges. The specific objectives are: To analyze the socio-historical determinants that influence the configuration of public policies in the area of mental health, demarcating the way in which they are responding to the growing demand of the disease of the chemical dependence and the place of the family in the agenda of these policies; To analyze the actions developed in the institutions dedicated to the treatment of chemical dependence, bearing in mind the bond or not of these institutions to the proposal of the Reform Psychiatrist and Antimanicomial Struggle; To identify how (and if it occurs) the attention to families (codependentes) during the treatment process of the user of psychoactive substances (SPA) - chemical dependent; To analyze the aspects that denote the visibility, the protagonism and the challenges of the relatives in the process of treatment, in the condition of codependentes. The paper articulates in its methodological course a bibliographical research, associated with a field research, in which a semistructured interview was applied with the research subjects, professionals of the institutions of the research universe and family members who during the period of field research were with some member Of their family in treatment. Regarding the results obtained in this research, it is important to highlight the position of the research subjects (health professionals and family members) in relation to the current services aimed at the treatment of chemical dependency and follow-up with the family, which in the scope of public mental health policy Becomes increasingly precarious. Concluding, therefore, the need to give greater visibility to the problematic of chemical dependence and the fragile strategies of coping with this problem that is configured as an expression of the social question; Requiring a differentiated look for all the actors involved in it: user, family and society.
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Monitoramento ecotoxicol?gico de ?gua e sedimento em reservat?rio urbano localizado na regi?o litor?nea do Nordeste brasileiroN?brega, Thiago Farias 20 February 2015 (has links)
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Previous issue date: 2015-02-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Os efeitos delet?rios das atividades humanas ao meio ambiente s?o temas de v?rios estudos e
consequentemente de mudan?as de paradigmas. Exemplo disso, ? que at? pouco tempo
acreditava-se em um infinito poder de dilui??o dos ecossistemas em rela??o aos agentes t?xicos,
e pouco se conhecia dos efeitos dos contaminantes aos organismos. Em ?reas de intenso
crescimento urbano ? comum o descarte indiscriminado de subst?ncias t?xicas e
consequentemente o desequil?brio das din?micas naturais dos ecossistemas. Dentre estes, os
lagos s?o complexos e importantes fontes de ?gua superficial, abrigam esp?cies e t?m influ?ncia
sobre o clima da regi?o ao seu redor. A Lagoa de Extremoz/RN, litoral Nordeste do Brasil, ?
um corpo h?drico localizado numa regi?o de r?pido crescimento urbano. Est? sob influ?ncia de
atividades rurais, urbanas e industriais, al?m do regime clim?tico prop?cio a per?odos
prolongados de estiagem. O abastecimento de cerca de 300.000 pessoas depende da estabilidade
h?drica dessa lagoa. O objetivo deste trabalho foi descrever as rela??es entre par?metros f?sicos,
componentes qu?micos e as respostas observadas nos ensaios ecotoxicol?gicos, buscando
informa??es sobre as varia??es sazonais. Para isso, foram realizadas, em dois anos, 2013 e
2014, an?lises f?sicas, qu?micas e ecotoxicol?gicas da ?gua e do sedimento superficial, em duas
esta??es de amostragem na Lagoa de Extremoz (T1 e T2) e uma no rio Guajiru (T3). Nas
amostras de ?gua foram aferidos o pH, turbidez, cloreto, OD, nitrato, nitrito, fosfato reativo
total, metais e dureza. Para avaliar a toxicidade das amostras foram usados Ceriodaphnia dubia
e C. silvestrii como organismos-teste. No sedimento foram aferidos os teores de carbonato,
mat?ria org?nica e metais, caracteriza??o granulom?trica e avaliado os efeitos t?xicos sobre a
sobreviv?ncia de Hyalella azteca. Verificou-se no per?odo de estiagem, ocorr?ncia de
toxicidade aguda aos Hyalella azteca e nesse mesmo per?odo as concentra??es de metais em
?gua e sedimento tamb?m foram maiores. Em uma an?lise espacial percebeu-se que a maioria
das amostras com efeito t?xico aos organismos-teste e com maiores concentra??es de metais
foram coletadas na esta??o T2. Portanto, existem evid?ncias de que a qualidade da ?gua da
Lagoa de Extremoz esteja diminuindo gradualmente e este processo se agrava pontualmente
nos per?odos de menor pluviometria e na esta??o de amostragem T2. / The deleterious effects of human activities on the environment, are subject of several studies
and therefore paradigm shifts. Until recently thought up in an infinite power dilution of
ecosystems in relation to toxic agents, and little was known of the effects of contaminants to
organisms. The intense urban growth contributes to the increase of toxic substances and the
instability of the environment dynamics. Among these, the lakes are complex ecosystems
important for sustaining life, by stock and provide water, to have influence on microclimates
and others. The Extremoz Lake/RN, northeastern Brazil, is a water body located in a fast urban
growth area. It is under the influence of rural, urban and industrial activities, further on the
climate regime conducive to prolonged periods of drought. The supply of approximately
300.000 people depended on the hydraulic stability of this lake The aim of this study was to
describe the relationship between physical, chemical components and the responses observed
in the ecotoxicological tests, seeking information on seasonal variations. Physical, chemical
and ecotoxicological analysis of water and surface sediment were held in two years, 2013 and
2014, in two sampling stations in Extremoz Lake (T1 and T2) and in Guajiru (T3) river. In all
the water samples were measured pH, turbidity, chloride, DO, nitrate, nitrite, the total reactive
phosphate, hardness and metals. Ceriodaphnia dubia and C. silvestrii as test organisms were
used to evaluate the toxicity of the water samples. In the sediment were measured the carbonate,
organic matter, metals, particle size, and evaluated the toxic effects on the survival of Hyalella
Azteca. In dry season occurred acute toxicity to Hyalella azteca and in the same period the
concentrations of metals in water and sediment were also higher. In a spatial analysis, it was
noticed that most of the samples with toxic effects on test organisms and with the highest metal
concentrations were collected at T2. So there is evidence that the Extremoz Lake quality is
gradually declining and this process is occasionally worsens during periods of lower rainfall
and sampling station T2.
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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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Desenvolvimento de cer?mica vermelha utilizando rejeitos da constru??o civilSilva, Juliana Em?dia de Oliveira 23 November 2007 (has links)
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Previous issue date: 2007-11-23 / The Industry of the Civil Construction has been one of the sectors that most contribute to the pollution of the environment, due to the great amount of residues
generated by the construction, demolition and the extraction of raw material. As a way of minimizing the environmental impacts generated by this industry, some governmental organizations have elaborated laws and measures about the disposal of residues from the building construction (CONAMA - resolution 307). This work has as objective the reutilization of residues compound of sand, concrete, cement, red
bricks and blocks of cement and mortar for the production of red ceramic, with the objective of minimizing costs and environmental impacts. The investigated samples
contained 0% to 50% of residues in weight, and they were sintered at temperatures of 950?C, 1000?C, 1050?C, 1100?C and 1150?C. After the sinterization, the samples
were submitted to tests of absorption of water, linear retraction, resistance to bending, apparent porosity, specific density, XRD and SEM. Satisfactory results were
obtained in all studied compositions, with the possible incorporation of up to 50% of residues in ceramic mass without great losses in the mechanical strength, giving
better results to the incorporation of 30% of residues in the fabrication of ceramic parts, such as roofing tiles, bricks masonry and pierced bricks / A ind?stria da constru??o civil tem sido um dos setores que mais tem contribu?do com a polui??o do meio ambiente devido a grande quantidade de res?duos gerados pela constru??o, demoli??o e extra??o de mat?ria prima. Como forma de minimizar os impactos ambientais gerados, alguns ?rg?os governamentais tem elaborado leis e medidas sobre a disposi??o de res?duos da constru??o civil (CONAMA resolu??o 307). Este trabalho tem como objetivo estudar o reaproveitamento de res?duos da constru??o civil composto de areia, concreto, cimento, tijolos vermelhos, e blocos de
cimento e argamassa na massa para fabrica??o de cer?mica vermelha, com o objetivo de minimizar custos e impactos ambientais gerados. As amostras investigadas continham 0% a 50% em peso de res?duo, sendo sinterizadas nas
temperaturas de 950?C, 1000?C, 1050?C, 1100?C e 1150?C. Ap?s a sinteriza??o as amostras foram submetidas a ensaios de absor??o de ?gua, retra??o linear, resist?ncia ? flex?o, porosidade aparente, massa espec?fica, DRX e MEV. Foram
obtidos resultados satisfat?rios em todas as composi??es estudadas, sendo poss?vel a incorpora??o de at? 50% de res?duo nas massas cer?micas sem grandes perdas
na resist?ncia mec?nica, apresentando melhores resultados para a incorpora??o de 30% de res?duos na massa de fabrica??o de pe?as cer?micas como telhas, tijolos de
alvenaria e furados
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Avalia??o da conformidade de blocos cer?micos para alvenaria de veda??o produzidas na Regi?o Integrada de Desenvolvimento da Grande TeresinaR?go, Vilson Ribamar 13 June 2008 (has links)
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Previous issue date: 2008-06-13 / This research presents an outlook of the industries of red ceramic in the region next to the city of Teresina and an analysis of the ceramic products producted in this pole. The microregion investigated possesses 13 boroughs where were identified 32 ceramic in
operation, being that 24 are located in Teresina, the ceramic region more important of Piau?, 1 is located in the city of Miguel Le?o and 7 is located in Timon city that belongs to the state of Maranh?o. The majority of ceramics are pulverized in these two cities, Teresina and Timon , responsible by a largely production independent of distance between fabric and consumer market. Furthermore, there is an artisanal production realized in other boroughs, mainly manual conformation bricks, where are producted diverse types of handicraft and ceramics utilitarian. The objective of this research is to evalue the conformity of ceramic blocks for brick of obstruction made by red ceramic industry of microregion at studying, verifying their pontentialities and adequacy in terms of production. In this research universe made a search of ceramic industries related to the Foundation CEPRO (Foundation Center of Research Social and Economic of Piau?). For the analysis of the ceramic products , were colected 60 crude bricks sample in three industries for their characterization, and 39 burned bricks sample for the Evaluation of Conformity. The results of the characterization made reached a accetptable standard in all formulations and temperature studied. The burned samples were applied to the geometric, physical and mechanical assays according to the ABNT standards (Brazilian Association of Technical Standards). The results of the physical assays showed that all the samples are at the same band recommended by standard. However, through the geometric assays just two industries did not present results according to the standard, due to lack of control in their process such as in their equipments. Taking into account the mechanical properties, only one industry investigated was not according to the standard / Esta pesquisa apresenta um panorama das ind?strias de cer?mica vermelha na Regi?o Integrada de Desenvolvimento da Grande Teresina e uma an?lise dos produtos cer?micos fabricados nesse p?lo. A microrregi?o em estudo possui 13 munic?pios onde foram identificadas 32 cer?micas em atividades, sendo que 24 est?o situadas na cidade de Teresina, o p?lo cer?mico de maior import?ncia do Piau?, 1 na cidade de Miguel Le?o e 7 no munic?pio de Timon, no vizinho estado do Maranh?o, que faz parte da grande Teresina. A maioria das cer?micas est? pulverizada nestas duas Cidades, Teresina e Timon, respons?veis por uma produ??o largamente independente da dist?ncia entre f?brica e mercado consumidor. Al?m dessas, h? a produ??o artesanal realizada nos demais munic?pios, principalmente, tijolos de conforma??o manual, onde tamb?m s?o produzidos diversos tipos de artesanato e utilit?rios cer?micos. O objetivo desta pesquisa ? avaliar a conformidade de blocos cer?micos para alvenaria de veda??o, produzidos pela ind?stria de cer?mica vermelha da microrregi?o em estudo, verificando suas potencialidades e adequa??o em termos produtivos. Para defini??o do universo da pesquisa, fez-se um levantamento das ind?strias cer?micas junto ? Funda??o CEPRO (Funda??o Centro de Pesquisas Econ?micas e Sociais do Piau?). Para a an?lise dos produtos cer?micos, foram coletadas 60 amostras de tijolos verdes em tr?s ind?strias, para a caracteriza??o desses produtos e 39 amostras de tijolos queimados, para a avalia??o da conformidade. Os resultados das caracteriza??es realizadas apresentaram um padr?o aceit?vel em todas as formula??es e temperaturas estudadas. As amostras queimadas foram submetidas aos ensaios geom?tricos, f?sicos e mec?nicos de acordo com as normas da ABNT (Associa??o Brasileira de Normas T?cnicas). Os resultados dos ensaios f?sicos mostraram que todas as amostras est?o dentro da faixa recomenda pela norma. J? nos ensaios geom?tricos, duas ind?strias apresentaram resultados n?o conforme com a norma, devido ? falta de controle nos seus processos e nos equipamentos. Quanto ?s propriedades mec?nicas, apenas uma ind?stria pesquisada n?o atendeu ? norma, devido ao fato do controle inadequado do seu processo
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Influ?ncia do lodo de ETE na massa para fabrica??o de cer?mica vermelhaAra?jo, Franciolli da Silva Dantas de 05 August 2008 (has links)
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Previous issue date: 2008-08-05 / The WTP produce many kinds of residue on your treatment stages, but the sludge is the more
problematic from the final disposition point view. The actual rate of residue production deriving from technological evolution and the crescent population needs prevents the subtle equilibrium generation between consumption and recycling/reuse, creating problems of
pollution resulting from inappropriate management of residues. Thus, is necessary achieve a new equilibrium between the grow from raw materials and energy and the residue generation. This equilibrium should be achieved by technical and economic feasibility of environmental
supported models through recycling and reuse. The red ceramic industry stand out in residue absorption question as raw material due their clay mass heterogeneity, constituted by clay minerals and non-clay minerals with wide mineralogical variation, allowing residue inclusion
which act like plastic or non-plastic materials, contributing to retain heavy metals contained in residues in the vitreous mass formed during the burning of the ceramic bodies. This work propose the study of the influence of incorporation of 25 wt.% sludge from wastewater
treatment plant, according preliminary results, in the mass to produce ceramic bodies. The raw materials was characterized through chemical composition analyses by XRF, mineralogical analyses by XRD, thermal analyses by TG and DTA, Atterberg limits and thermodilatometry. Subsequently was composed the mass with 75 wt.% of clay and 25 wt.% of dried wastewater sludge from UFRN WWTP. Samples with 6,0 x 2,0 x 0,5 cm was produced with unidirectional compacting under pressure of 20MPa and burned in temperatures between 950 and 1,200?C. After fired, the ceramic bodies have been submitted
to physical and mechanical analyses through the measure of firing shrinkage, water absorption, density, apparent porosity and flexural strength; crystallographic analyses through XRD and microstructure analyses by SEM. The technological properties obtained was satisfactory to production of roof tiles with 25 wt.% at 1,200 ?C, but the production of others products at lower temperatures was not feasible / As ETE produzem v?rios tipos de res?duos em suas etapas de tratamento, mas o lodo ? o res?duo mais problem?tico do ponto de vista de disposi??o final. A atual taxa de gera??o de res?duos, acarretada da evolu??o tecnol?gica e da crescente demanda populacional, impede a gera??o de um equil?brio h?bil entre o consumo e a reciclagem/reuso, gerando problemas de polui??o resultantes da gest?o inadequada dos res?duos. Dessa forma, ? necess?rio atingir um novo equil?brio entre o crescimento das demandas por mat?rias e energia e a gera??o de res?duos. Este equil?brio, s? pode ser alcan?ado atrav?s da viabiliza??o t?cnica e econ?mica
de modelos de sustentabilidade ambiental, atrav?s da reciclagem e do reuso. A ind?stria de cer?mica vermelha se destaca no quesito absor??o de res?duos como mat?ria-prima em virtude da heterogeneidade das massas argilosas, constitu?das de argilominerais e minerais n?o argilosos com ampla varia??o mineral?gica, permitindo a inclus?o de res?duos que atuem como plastificantes ou desplastificantes, e contribuindo tamb?m para a reten??o de metais pesados presentes nos res?duos na massa v?trea formada nos corpos cer?micos. Este trabalho prop?e estudar a influ?ncia da incorpora??o de 25% de lodo de esta??o de tratamento de esgoto, baseado em resultados preliminares, ? massa para produ??o de corpos cer?micos. As mat?rias-primas foram caracterizadas atrav?s de an?lise da composi??o qu?mica por FRX, an?lise mineral?gica por DRX, an?lise t?rmica por TG e DTA, an?lise dos limites de Atterberg e an?lise dilatom?trica. Em seguida foi composta a massa com 75% de argila e 25% em peso de lodo da ETE UFRN. Foram prensados corpos-de-prova com dimens?es 6,0 x 2,0
x 0,5 cm atrav?s de prensagem uniaxial sob press?o de 20MPa e queimadas nas temperaturas entre 950 e 1200?C. Ap?s a sinteriza??o, os corpos-de-prova foram submetidos a ensaios f?sico-mec?nicos atrav?s de medida de retra??o linear, absor??o de ?gua, massa espec?fica
aparente, porosidade aparente e tens?o de ruptura ? flex?o; an?lise cristalogr?fica atrav?s de DRX e an?lise microestrutural atrav?s de MEV. As propriedades tecnol?gicas obtidas mostraram-se satisfat?rias para fabrica??o de telhas com 25% de lodo na temperatura de
queima de 1.200 ?C, n?o sendo vi?vel a fabrica??o de outros produtos em temperaturas inferiores
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