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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

Reconhecimento de padr?es pela casca de jabuticaba (Myrciaria jabuticaba (Vell) Berg (jabuticaba sabar?)) e de refrigerante do guaran? (Paullinia cupana) usando infravermelho pr?ximo e quimiometria

Pedrosa, Nascilaine Osanilha Costa January 2012 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-19T13:03:29Z No. of bitstreams: 5 nascilaine.pdf: 1827154 bytes, checksum: b9e52778b31d948210ff6f1f431250cf (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-20T09:45:45Z (GMT) No. of bitstreams: 5 nascilaine.pdf: 1827154 bytes, checksum: b9e52778b31d948210ff6f1f431250cf (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Made available in DSpace on 2015-02-20T09:45:45Z (GMT). No. of bitstreams: 5 nascilaine.pdf: 1827154 bytes, checksum: b9e52778b31d948210ff6f1f431250cf (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) Previous issue date: 2013-02-21 / Na primeira parte do trabalho foi proposto o reconhecimento de padr?es de jabuticaba (Myrciaria jabuticaba (vell) berg (jabuticaba sabar?)) pela avalia??o dos elementos boro, nitrog?nio, magn?sio, f?sforo, pot?ssio, c?lcio, mangan?s, ferro, cobre e zinco na casca empregando-se as t?cnicas de titula??o, espectroscopia de absor??o at?mica e molecular. Os dados obtidos pelas an?lises dos elementos foram dispostos em matriz 7 x 10, sendo sete amostras referente ?s sete cidades analisadas (S?o Jo?o da Chapada, Gouveia, Guinda, Couto de Magalh?es, Po?os de Caldas, Belo Horizonte e Serro) e dez vari?veis correspondendo ?s concentra??es dos elementos determinadas em mgk-1. O reconhecimento de padr?es foi feito empregando-se a An?lise das Componentes Principais e An?lise Hier?rquica por Agrupamentos. Desta forma foi poss?vel identificar pela An?lise das Componentes Principais os grupos formados pela semelhan?a, baseados nos pesos correspondentes ?s influ?ncias das vari?veis. Cerca de cinco componentes principais acumularam 97,47% da vari?ncia total dos dados sendo que a componente principal de n?mero um (01) acumulou cerca de 38,21% da vari?ncia e a componente principal de n?mero tr?s (03) cerca de 16,13% da vari?ncia. Os grupos formados na An?lise das Componentes Principais foram confirmados na An?lise Hier?rquica por Agrupamento, sendo formado quatro grupos, denotando a maior semelhan?a nas amostras de Gouveia e Couto Magalh?es. Na segunda etapa do estudo teve por finalidade classificar e caracterizar quimicamente o refrigerante do tipo guaran?, em diferentes estados brasileiros, foram analisadas suas concentra??es de metais e diferentes compostos atrav?s da absor??o at?mica e espectroscopia de infravermelho respectivamente. Para classificar os refrigerantes dos diversos locais, foi utilizada nos resultados obtidos das an?lises a an?lise explorat?ria baseada em An?lise das Componentes Principais (PCA). A melhor separa??o se deu com as vari?ncias acumuladas na CP2 e CP4, onde as amostras de refrigerantes zero formaram um grupo e amostras coletadas no RJ outro grupo e as amostras de Shim tamb?m formaram um grupo diferente dos demais. Como conclus?o pode-se salientar que os m?todos de reconhecimento de padr?es empregados neste trabalho apresentaram resultados que possibilitam a diferencia??o das amostras em locais distintos. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012. / ABSTRACT In the first part of the proposed pattern recognition Jabuticaba (Myrciaria jabuticaba (vell) berg (jabuticaba sabar?)) for the evaluation of the elements boron, nitrogen, magnesium, phosphorus, potassium, calcium, manganese, iron, copper and zinc on the shell employing the techniques of titration, atomic absorption spectroscopy and molecular. The data obtained by analysis of the elements were arranged in a matrix 10 x 7, seven samples analyzed referring to the seven cities (S?o Jo?o da Chapada, Gouveia, Guinda, Couto de Magalhaes, Wells Caldas, Belo Horizonte and Serro) and ten variables corresponding concentrations of certain elements in MGK-1. Pattern recognition was done using the Analysis of Principal Components Analysis for Hierarchical Groups. This made it possible to identify the Principal Component Analysis groups formed by similarity, based on the weights corresponding to the influences of variables. About five main components accumulated 97.47% of the total variance of the data being the main component of a number (01) accumulated approximately 38.21% of the variance and the principal component number three (03) approximately 16.13% variance. The groups formed in the Principal Component Analysis were confirmed in the Hierarchic Cluster Analysis, formed four groups, indicating a greater similarity in the samples of Gouveia and Couto Magalh?es. In the second stage of the study aimed to classify and characterize chemically the guarana soda type, in different Brazilian states were analyzed in relation to different concentrations of metals and compounds by atomic absorption and infrared spectroscopy respectively. To sort the drinks at different locations, we used the results of the analyzes exploratory analysis based on Principal Component Analysis (PCA). The best separation was accumulated at variance with the CP2 and CP4, where samples of soft drinks have formed a group and zero samples collected at the RJ and the other group samples Shim also formed a different group of demais. Como conclusion can be noted that methods of pattern recognition in this work presented results that allow the differentiation of samples at different locations.
2

Avalia??o da influ?ncia da mat?ria org?nica, na determina??o quantitativa de metais em amostras de sedimento, por espectrometria de absor??o at?mica e an?lise de metais tra?os por fluoresc?ncia de raios-X

Martins, Ilton S?vio Batista 21 February 2011 (has links)
Made available in DSpace on 2014-12-17T15:41:54Z (GMT). No. of bitstreams: 1 IltonSBM_DISSERT.pdf: 1681110 bytes, checksum: cc6a556fbd04c8fc33747969d0ee11f6 (MD5) Previous issue date: 2011-02-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The proposal of this work is to evaluate the influence of the organic matter on the results of the analyses of the metals (Zn, Pb, Al, Cu, Cr, Fe, Cd e Ni) for Atomic Absorption Spectrometry (AAS), so much in the extraction stage as in the reading using for that the chemometrics. They were used for this study sample of bottom sediment collected in river Jundia? in the vicinity of the city of Maca?ba-RN, commercial humus and water of the station of treatment of sewer of UFRN. Through the analyses accomplished by EAA it was verified that the interference of the organic matter happens in the extraction stage and not in the reading. With relationship to the technique of X Ray Fluorescence Spectrometry (XRFS), the present work has as intended to evaluate the viability of this technique for quantitative analysis of trace metals (Cr, Ni, Cu, Zn, Rb, Sr and Pb) in having leached obtained starting from the extraction with acqua regia for an aqueous solution. The used samples constitute the fine fraction (<0.063 mm) of sediments of swamp of the river Jundia?. The preparation of tablets pressed starting from the dry residue of those leached it allowed your analysis in the solid form. This preliminary study shows that, in the case of the digestion chemistry partially of the fine fractions of bottom sediments used for environmental studies, the technique of applied EFRX to the analysis of dry residues starting from having leached with acqua regia, compared her it analyzes of the leached with ICP-OES, it presents relative mistakes for Cu, Pb, Sr and Zn below 10% / A proposta deste trabalho ? avaliar a influ?ncia da mat?ria org?nica sobre os resultados das an?lises dos metais (Zn, Pb, Al, Cu, Cr, Fe, Cd e Ni) por Espectrometria de Absor??o At?mica (EAA), tanto na etapa de extra??o quanto na leitura utilizando para isso a quimiometria. Foram utilizados para este estudo amostra de sedimento de fundo coletadas no Rio Jundia? nas imedia??es da cidade de Maca?ba-RN, h?mus comercial e ?gua da esta??o de tratamento de esgoto da UFRN. Atrav?s das an?lises realizadas por EAA verificou-se que a interfer?ncia da mat?ria org?nica ocorre na etapa de extra??o e n?o na leitura. Com rela??o ? t?cnica de Espectrometria de Fluoresc?ncia de Raio-X (EFRX), o presente trabalho tem como proposta avaliar a viabilidade desta t?cnica para an?lise quantitativa de metais tra?os (Cr, Ni, Cu, Zn, Rb, Sr e Pb) em lixiviados obtidos a partir da extra??o com ?gua r?gia para uma solu??o aquosa. As amostras utilizadas constituem a fra??o fina (< 0.063 mm) de sedimentos de mangue do Rio Jundia?. A prepara??o de pastilhas prensadas a partir do res?duo seco dos lixiviados permitiu sua an?lise na forma s?lida. Este estudo preliminar mostra que, no caso da digest?o qu?mica parcial das fra??es finas de sedimentos de fundo utilizadas para estudos ambientais, a t?cnica de EFRX aplicada ? an?lise de res?duos secos a partir de lixiviados com ?gua r?gia, comparada a analise do lixiviado com ICP-OES, apresenta erros relativos para Cu, Pb, Sr e Zn abaixo de 10%

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