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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Influ?ncia das condi??es meteorol?gicas na concentra??o de rad?nio em ?rea de caatinga e mata atl?ntica dunar / Influence of weather conditions in radon concentration in caatinga area and atlantic dune

Dantas, Vanessa de Almeida 31 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T23:04:25Z No. of bitstreams: 1 VanessaDeAlmeidaDantas_TESE.pdf: 3738312 bytes, checksum: de5a62b1338eeb90aff1798f2d02d2e7 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-14T00:07:59Z (GMT) No. of bitstreams: 1 VanessaDeAlmeidaDantas_TESE.pdf: 3738312 bytes, checksum: de5a62b1338eeb90aff1798f2d02d2e7 (MD5) / Made available in DSpace on 2017-03-14T00:07:59Z (GMT). No. of bitstreams: 1 VanessaDeAlmeidaDantas_TESE.pdf: 3738312 bytes, checksum: de5a62b1338eeb90aff1798f2d02d2e7 (MD5) Previous issue date: 2016-08-31 / O Rad?nio (Rn-222) ? um g?s nobre-radiativo, incolor, inodoro, ins?pido, denso (9,73 kg/m3) e altamente sol?vel na ?gua (solubilidade de 1,67x10-4 a 25?C e 1Atm) que, com exce??o do Di?xido de Carbono, ? o g?s com maior solubilidade na Atmosfera. Neste estudo foram analisadas a varia??o e correla??o das vari?veis meteorol?gicas com as emana??es de Rad?nio e ?ons atmosf?ricos em um ambiente de floresta equatorial e Caatinga do estado do Rio Grande do Norte, Brasil. Especificamente em biomas do Nordeste do Brasil (NEB) pouco se sabe sobre o comportamento Rn-222, no que diz respeito ? distribui??o nos diferentes n?veis da baixa troposfera, a exemplo da Mata Atl?ntica Dunar e Caatinga. Assim, o objetivo foi de investigar a rela??o entre vari?veis meteorol?gicas, as concentra??es atmosf?ricas de Rn-222 e ?ons atmosf?ricos para o per?odo caracterizado como seco e chuvoso, no munic?pio de Apod?-RN e Parnamirim-RN no per?odo seco, inseridos no bioma de Caatinga e Mata Atl?ntica Dunar Nordestina que abrange cerca de 800.000 Km2 e 19.427 km?, respectivamente. As medidas foram realizadas a 1,5 m do solo. Coletaram-se dados de temperatura do ar, umidade relativa, velocidade e dire??o do vento e press?o atmosf?rica bem como concentra??es de Rn-222 e de ?ons atmosf?ricos. Os resultados mostraram um padr?o bimodal no comportamento di?rio da concentra??o de Rn-222, nas primeiras horas da manh? observado em todos os dias. Comportamento semelhante foi observado para a concentra??o de ?ons entre 04:00 e 05:00 HL (Hor?rio Local) em Parnamirim. Em Apod?, o ciclo di?rio da concentra??o de Rn-222 mostrou um padr?o semelhante ao de Parnamirim, com um m?ximo principal de 29,38 Bq/m3 e 24,00 Bq/m3 durante a esta??o seca e chuvosa, respectivamente, em torno de 17:00 HL e um m?ximo secund?rio ?s 15:00 HL com 27,37 Bq/m3 (esta??o seca) e 19,00 Bq/m3 (esta??o chuvosa). Estes ciclos s?o consistentes com situa??es de uma atmosfera estaticamente neutra devido ? transi??o de per?odos de est?vel para regimes inst?veis (primeiro pico) e inst?veis para est?vel (segundo pico) de acordo com o n?mero de Richardson Bulk tamb?m observado neste estudo. Atrav?s do modelo de regress?o linear m?ltipla via an?lise de componentes principais as vari?veis meteorol?gicas que se mostraram mais correlacionadas com a concentra??o de Rn-222, com explica??o de 88% foram a umidade relativa, velocidade do vento e a radia??o solar global. / The Radon (Rn-222) is a radioactive noble-gas, colorless, odorless, tasteless, dense (9.73 kg / m3) and highly soluble in water (solubility 1,67x10-4 25 ? C and 1 atm) that, except for carbon dioxide is the gas with greater solubility in the atmosphere. This study analyzed the variation and correlation of meteorological variables with the emanations of Radon and atmospheric ions in a rainforest environment and Caatinga in the state of Rio Grande do Norte, Brazil. Specifically, in Northeast biomes of Brazil (NEB) little is known about the Rn-222 behavior in relation to the distribution in the different levels of the lower troposphere, such as the Atlantic Forest Dune and Caatinga. The objective was to investigate the relationship between meteorological variables, atmospheric concentrations of Rn-222 and atmospheric ions to the period characterized as dry and rainy in the municipality of Apodi-RN and Parnamirim-RN in the dry season, entered in the biome Caatinga and Northeast Atlantic Forest Dune which covers about 800,000 km2 and 19,427 square kilometers respectively. The measurements were taken at 1.5 m above the ground. Collected from the air temperature data, relative humidity, wind speed and direction, atmospheric pressure and Rn-222 and atmospheric ion concentrations. The results showed bimodal pattern in the daily behavior of the concentration of Rn-222, in the early morning hours observed in every day. Similar behavior was observed for the concentration of ions between 04:00 and 05:00 HL (Local Time) in Parnamirim. In Apodi, the daily cycle of concentration of Rn-222 showed a pattern similar to Parnamirim, with a maximum principal of 29.38 Bq / m3 and 24.00 Bq / m3 during the dry and rainy seasons, respectively, around 17:00 HL and a secondary maximum at 15:00 HL with 27.37 Bq / m3 (dry season) and 19.00 Bq / m3 (rainy season). These cycles are consistent with conditions of a statically neutral atmosphere due to the periods of transition from stable to unstable regimes (first peak) and unstable stable (second peak) according to the Richardson number Bulk also observed in this study. Through multiple linear regression model via principal component analysis the meteorological variables that were more correlated with the concentration of Rn-222, with 88% explanation were the relative humidity, wind speed and solar radiation.
2

An?lise da toxicidade no a?ude Riacho da Cachoeira, Lajes Pintadas (RN): um desafio interdisciplinar

Dantas, Richelly da Costa 06 February 2012 (has links)
Made available in DSpace on 2014-12-17T15:54:58Z (GMT). No. of bitstreams: 1 RichellyCD_DISSERT.pdf: 2320293 bytes, checksum: 0a60ecea735c1b5c6fe1a9d05e141fe9 (MD5) Previous issue date: 2012-02-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Contamination by complex mixtures of various origins has been explored and studied for decades. Radon is a naturally occurring environmental contaminant that causes carcinogenic effects. These emissions can cause mutations in the lung tissue, which can initiate a carcinogenic process. Thus the dam Creek Falls, located in the municipality of Lajes Pintadas, was chosen for the development of this study, since cancer rates in the region reach 9% of the population annually, with this, the main objective of this study was evaluate the mutagenicity and toxicity of Riacho da Cachoeira damunder the influence of radon. The methodology ecotoxicological tests were performed with Ceriodaphinia dubia, as well as tests with Tradescantia pallida genotoxicologicos and Oreochromis niloticus. To understand how the population of Pintadas Slabs realizes the environment, we performed a study of environmental perception. The test results indicated that the reservoir water is toxic to test organimos exposed, found heavy metals, chloride, total and fecal coliforms as well as radon levels above the maximum allowed under Brazilian law. These results can be justified because it is so complex samples composed of different compounds that interact only with each other or causing synergistic effects. It was concluded that the dam Creek Waterfall, is contaminated with radon, as well as heavy metals, coliforms and chloride, causing toxic effects to the natural community. Thus, further studies should be performed with the human population of the region, to verify that the high rates of cancer in the population of the municipality may be linked to the presence of natural radiation. Thus, it is expected that the competent bodies that administer the municipality of Lajes Pintadas take reasonable steps to minimize risks and ensure the health of the community that still makes use of the weir / A contamina??o por misturas complexas de origens diversas vem sendo explorada e estudada por d?cadas. O rad?nio ? um contaminante ambiental de origem natural, que provoca efeitos carcinog?nicos. Estas emiss?es podem levar as muta??es no tecido do pulm?o, que podem iniciar um processo carcinog?nico. Assim o a?ude Riacho da Cachoeira, localizado no munic?pio de Lajes Pintadas, foi escolhido para o desenvolvimento do presente estudo, j? que h? altas taxas de c?ncer na regi?o que chegam a 9% da popula??o, anualmente, com isso, o objetivo principal do presente estudo foi avaliar a mutagenicidade e toxicidade do a?ude Riacho da Cachoeira sob a influ?ncia do Rad?nio. Como metodologia, foram realizados ensaios ecotoxicologicos com Ceriodaphinia dubia, assim como ensaios genotoxicologicos com Tradescantia pallida e Oreochromis niloticus. Para entender como a popula??o de Lajes Pintadas percebe o meio ambiente, foi realizado um estudo de percep??o ambiental. Os resultados dos ensaios indicaram que a ?gua do a?ude ? toxica aos organimos-teste expostos, foram encontrados metais pesados, cloreto, coliformes totais e fecais assim como os n?veis de rad?nio acima dos limites m?ximos permitidos segundo a legisla??o brasileira. Os resultados encontrados podem ser justificados pelo fato de se tratar de amostras complexas constitu?das assim de diferentes compostos que interagem s? ou entre si causando efeitos sin?rgicos. Concluiu-se que o a?ude Riacho da Cachoeira, est? contaminado com rad?nio, assim como por metais pesados, coliformes e cloreto, causando efeitos toxicol?gicos ? comunidade natural. Assim, novos estudos devem ser realizados com a popula??o humana da regi?o, para verificar se os altos ?ndices de c?ncer na popula??o do munic?pio podem estar ligados a presen?a da radia??o natural. Desta forma, espera-se que os ?rg?os competentes que administram o munic?pio de Lajes Pintadas tomem medidas cab?veis para assegurar e minimizar os riscos a sa?de da comunidade que ainda faz uso do a?ude

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