Seminario de Título entregado a la Universidad de Chile en cumplimiento parcial de los requisitos para optar al Título de Químico Ambiental / Iron (Fe) is a transition metal usually found in potable water at low concentrations, whose concentration limit is 0.3 mg / L according to NCh 409, and due to its common use mainly in pipelines and industries, it must be constantly monitored, in order to keep its concentration under the limits and guarantee the welfare of people. The aim of this work is to promote an easy method to identify and extract Fe from potable and natural waters through solid phase extraction. This was done both for acid and basic mediums. 0.4 mL of sulfosalicylic acid (SSA) at 2.5% w/v was used as a ligand, adding 3 mL of a monochloroacetic acid buffer for the samples in acid medium and 3 mL of concentrated NH3 (12,66 M) for samples in basic medium and form a complex, either Fe(III)-SSA or Fetotal-SSA, in 100 mL total solution. Then, an anion exchange solid resin was added, called AG 2-x8 from BIORAD, in order to preconcentrate the complex. Previous studies were conducted without the addition of resin to observe the formation of the complex and study its characteristics. The quantification limits were 0.56 ppm and 0.28 ppm, which are very high or too close to the concentration limit of Fe allowed in potable water, that is, 0.3 ppm (NCh 409). Solid phase studies were carried out in order to decrease the quantification limits of the method. Then the chemical variables involved in obtaining the complex were optimized, such as the amount of SSA, anionic resin, buffer and total volume. Thus obtaining the adequate amounts for each analyte, mentioned above. The extraction of the Fe-ASS complex was possible for both media. However, in a basic medium it requires much higher Fe concentrations for its formation and presented a constant turbidity in the form of a colloidal compound of gray tone mainly referred so the procedure was more thoroughly studied in acid medium. The Fe(III)-SSA complex presented good linearity throughout the measurement range with an DL of 7.32 x 10-3 ppm and an QL of 0.024 ppm achieving a good sensitivity and a recovery percentage of 99.7%. Only SO4-2 presented interference in the sample with a tolerance limit of only 100 ppm. The standard addition method was effective to eliminate this interference by treating the entire matrix in the same way throughout the measurement range. Potable water samples were taken from different sources, such as, from the Analytic Chemistry Laboratory (Ñuñoa), Quinta Normal and from a construction zone adjacent of the the Faculty of Sciences of the University of Chile. Fe is generally found at concentrations below the norm (23.38 ppb and 172 ppb), but is sensitive to climatic factors (522 ppb after a very rainy day) and construction places with little waste treatment (342.3 ppb), so it must be constantly monitored. Solid phase extraction is a simple, fast and efficient method and has a wide range of applications for different compounds or chemical substances.

Nossa investigação explora a possibilidade de o tema da paideia ser um eixo comum em torno do qual se articulam os textos de Xenofonte de Atenas, autor do século IV a.C. Julgamos que essa perspectiva se justifica em razão da importância que esse autor atribui à construção de retratos de homens paradigmáticos. Ilustramos esse procedimento com a análise do retrato que o próprio Xenofonte constrói para si, na Anabase. É sobretudo a partir da análise desses retratos que podemos ver, em Xenofonte, a discussão do tema da paideia. Os estudos que aqui empreendemos concentram-se no tema da paideia do governante. Nesse horizonte, oferecemos uma possível leitura para o retrato daquele que o autor considera a contrafacção do governante ideal, o tirano Hierão, de diálogo homônimo. Por fim, ocupamo-nos dos elementos que compõem o retrato xenofôntico do governante paradigmático, Ciro, o velho, da Ciropédia. / Our research explores the possibility of the theme of paideia as a common axis around which are articulated the texts of Xenophon of Athens, author of the fourth century BC. We believe that this perspective is justified because of the importance this author gives to the construction of portraits of paradigmatic men. We illustrate this procedure with the analysis of the portrait which Xenophon builds for himself in the Anabasis. It is mainly based on the analysis of such portraits that we can see, in Xenophon, the discussion on the theme of paideia. The studies undertaken here focus on the theme of the ruler\'s paideia. In this horizon, we offer a possible reading for the portrait of the man the author considers the counterfeiting of the ideal ruler, the tyrant Hiero, in the corresponding dialogue. Finally we deal with the elements that make up the portrait of Xenophons paradigmatic ruler, Cyrus the Great, of the Cyropaedia.

Nossa investigação explora a possibilidade de o tema da paideia ser um eixo comum em torno do qual se articulam os textos de Xenofonte de Atenas, autor do século IV a.C. Julgamos que essa perspectiva se justifica em razão da importância que esse autor atribui à construção de retratos de homens paradigmáticos. Ilustramos esse procedimento com a análise do retrato que o próprio Xenofonte constrói para si, na Anabase. É sobretudo a partir da análise desses retratos que podemos ver, em Xenofonte, a discussão do tema da paideia. Os estudos que aqui empreendemos concentram-se no tema da paideia do governante. Nesse horizonte, oferecemos uma possível leitura para o retrato daquele que o autor considera a contrafacção do governante ideal, o tirano Hierão, de diálogo homônimo. Por fim, ocupamo-nos dos elementos que compõem o retrato xenofôntico do governante paradigmático, Ciro, o velho, da Ciropédia. / Our research explores the possibility of the theme of paideia as a common axis around which are articulated the texts of Xenophon of Athens, author of the fourth century BC. We believe that this perspective is justified because of the importance this author gives to the construction of portraits of paradigmatic men. We illustrate this procedure with the analysis of the portrait which Xenophon builds for himself in the Anabasis. It is mainly based on the analysis of such portraits that we can see, in Xenophon, the discussion on the theme of paideia. The studies undertaken here focus on the theme of the ruler\'s paideia. In this horizon, we offer a possible reading for the portrait of the man the author considers the counterfeiting of the ideal ruler, the tyrant Hiero, in the corresponding dialogue. Finally we deal with the elements that make up the portrait of Xenophons paradigmatic ruler, Cyrus the Great, of the Cyropaedia.

Leonardo Bruni published one of his most widely copied translations, Xenophon's pro-monarchical Hiero, shortly before he penned his more famous original works, his Dialogues and Panegyric to the City of Florence. Scholars have traditionally focused on the political ideas present in these original treatises; yet, despite the centrality of political ideas to the Hiero, its temporal proximity to these works, and its enormous popularity (the work exists in 200 fifteenth-century manuscripts), scholars have neglected to offer a full assessment of Bruni's translation in the context of these works. Bruni's translation of Xenophon's Hiero fit into a debate in early fifteenth-century Florence about Julius Caesar and the Florentine poet Dante. The two major thinkers in the debate, Bruni and Coluccio Salutati, agreed that a distinction had to be made between kings and tyrants based on legal claim and quality of rule. The Hiero reinforced this assumption. The two men disagreed, however, about which category applied to Julius Caesar and what this meant for the reputation of Dante.

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-28T15:03:54Z No. of bitstreams: 1 Danilo Albuquerque de Campos.pdf: 453917 bytes, checksum: 1b07ec11128857b2e96af37543e335fe (MD5) / Made available in DSpace on 2017-03-28T15:03:55Z (GMT). No. of bitstreams: 1 Danilo Albuquerque de Campos.pdf: 453917 bytes, checksum: 1b07ec11128857b2e96af37543e335fe (MD5) Previous issue date: 2014-08-22 / In this work we are interested in showing three algorithms rational approximation of square roots by methods unknown or underutilized by teachers of elementary and secondary education. We begin by defining numerical sequence and convergence of sequences, will discuss the need to expand the concept of rational number and demonstrate the irrationality of the diagonal of a square. Prove an important theorem known in the literature as Dirichlet’s theorem and finally elencaremos three methods of approximating the square roots of natural non-perfect square numbers, very simple to be worked on in the classroom that are rational algorithm aproximção of Hiero of Alexandria, Theon’s Ladder and the Pell-Fermat equation, sende latter discursão fundamental to who will perform on the relationship of the three methods presented. / Neste trabalho estamos interessados em mostrar três algoritmos de aproximação racional de raízes quadradas por métodos pouco utilizados ou desconhecidos pelos professores do ensino fundamental e médio. Iniciaremos definindo sequência numérica e convergência de sequências, discutiremos sobre a necessidade de ampliação do conceito de número racional e demonstraremos a irracionalidade da diagonal de um quadrado. Provaremos um importante Teorema conhecido na literatura como o Teorema de Dirichlet, e por fim elencaremos três métodos de aproximação de raízes quadradas de números naturais não quadrados perfeitos, muito simples de serem trabalhados em sala de aula que são: O algoritmo de aproximação racional de Hierão de Alexandria, A escada de Theon e a Equação de Pell-Fermat, sendo este último fundamental para discussão que iremos realizar sobre a relação dos três métodos apresentados.