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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

Valida??o de um m?todo anal?tico para a determina??o de chumbo, c?dmio e merc?rio em pilhas alcalinas

Schuh, Alexandra Janine 27 March 2012 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-07-10T11:39:38Z No. of bitstreams: 1 471999 - Texto Completo.pdf: 2373737 bytes, checksum: 065804161c759cccca6c7119ea152d3f (MD5) / Made available in DSpace on 2015-07-10T11:39:38Z (GMT). No. of bitstreams: 1 471999 - Texto Completo.pdf: 2373737 bytes, checksum: 065804161c759cccca6c7119ea152d3f (MD5) Previous issue date: 2015-03-27 / People have rampantly consumed batteries, thereby obtaining mobile, low cost and highly durable energy. However, many consumers do not recognize that these batteries may contain high level of heavy metals in their composition and so discard them inappropriately with their household trash daily. In order to minimize the problems caused by batteries to the environment, legislations have been created throughout the world. In Brazil, Resolution CONAMA 401 of 2008 established the maximum levels of toxic metals in batteries. This thesis was developed with the objective of verifying the levels of cadmium, lead and mercury in order to validate an analytical method for the determination of theses toxic metals in alkaline batteries. 193 samples of alkaline batteries collected from the Brazilian market between 2010 and 2011 were evaluated; none of the evaluated samples had cadmium levels above the allowed maximum (0.002%). However, 10 samples were found to have levels of mercury that exceeded the allowed maximum of 0.0005% and 8 of the analyzed batteries had levels of lead that were higher than the allowed (0.1%). The results obtained show a high percentage of failure (9.3%) of the samples analyzed, which indicates the necessity of controlling the use of toxic metals. / A popula??o tem consumido desenfreadamente pilhas e baterias, obtendo assim energia m?vel de baixo custo e alta durabilidade. Muitas vezes n?o tendo o conhecimento de que estas pilhas e baterias possuem metais t?xicos em sua constitui??o, o descarte ? feito de forma inadequada, milhares de pilhas sendo descartadas em lixo comum diariamente. Para minimizar os problemas causados pelas pilhas ao meio ambiente, legisla??es foram criadas em diversas partes do mundo. No Brasil a Resolu??o CONAMA 401 de 2008 estabelece os limites m?ximos de metais t?xicos em pilhas e baterias. Com o objetivo de verificar os n?veis de c?dmio, chumbo e merc?rio, o presente trabalho foi desenvolvido para validar um m?todo anal?tico para a determina??o destes elementos t?xicos presentes em pilhas alcalinas. Foram avaliadas 193 amostras coletadas no mercado brasileiro nos anos de 2010 e 2011. Nenhuma das amostras possu?a quantidade de c?dmio acima do estipulado (0,002%). Por?m dez e oito amostras apresentaram concentra??o de Hg (0,0005%) e Pb (0,1%) excedendo o limite ambiental, respectivamente. Os resultados obtidos indicaram percentual de reprova??o elevado (9,30%) para as pilhas alcalinas ensaiadas, indicando a necessidade do controle desses metais.
2

Validação de um método analítico para a determinação de chumbo, cádmio e mercúrio em pilhas alcalinas

Schuh, Alexandra Janine January 2012 (has links)
Made available in DSpace on 2015-07-11T02:05:56Z (GMT). No. of bitstreams: 1 000471999-Texto+Completo-0.pdf: 2373737 bytes, checksum: 065804161c759cccca6c7119ea152d3f (MD5) Previous issue date: 2012 / People have rampantly consumed batteries, thereby obtaining mobile, low cost and highly durable energy. However, many consumers do not recognize that these batteries may contain high level of heavy metals in their composition and so discard them inappropriately with their household trash daily. In order to minimize the problems caused by batteries to the environment, legislations have been created throughout the world. In Brazil, Resolution CONAMA 401 of 2008 established the maximum levels of toxic metals in batteries. This thesis was developed with the objective of verifying the levels of cadmium, lead and mercury in order to validate an analytical method for the determination of theses toxic metals in alkaline batteries. 193 samples of alkaline batteries collected from the Brazilian market between 2010 and 2011 were evaluated; none of the evaluated samples had cadmium levels above the allowed maximum (0. 002%). However, 10 samples were found to have levels of mercury that exceeded the allowed maximum of 0. 0005% and 8 of the analyzed batteries had levels of lead that were higher than the allowed (0. 1%). The results obtained show a high percentage of failure (9. 3%) of the samples analyzed, which indicates the necessity of controlling the use of toxic metals. / A população tem consumido desenfreadamente pilhas e baterias, obtendo assim energia móvel de baixo custo e alta durabilidade. Muitas vezes não tendo o conhecimento de que estas pilhas e baterias possuem metais tóxicos em sua constituição, o descarte é feito de forma inadequada, milhares de pilhas sendo descartadas em lixo comum diariamente. Para minimizar os problemas causados pelas pilhas ao meio ambiente, legislações foram criadas em diversas partes do mundo. No Brasil a Resolução CONAMA 401 de 2008 estabelece os limites máximos de metais tóxicos em pilhas e baterias. Com o objetivo de verificar os níveis de cádmio, chumbo e mercúrio, o presente trabalho foi desenvolvido para validar um método analítico para a determinação destes elementos tóxicos presentes em pilhas alcalinas. Foram avaliadas 193 amostras coletadas no mercado brasileiro nos anos de 2010 e 2011. Nenhuma das amostras possuía quantidade de cádmio acima do estipulado (0,002%). Porém dez e oito amostras apresentaram concentração de Hg (0,0005%) e Pb (0,1%) excedendo o limite ambiental, respectivamente. Os resultados obtidos indicaram percentual de reprovação elevado (9,30%) para as pilhas alcalinas ensaiadas, indicando a necessidade do controle desses metais.

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