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Pictures of processes : automated graph rewriting for monoidal categories and applications to quantum computingKissinger, Aleks January 2011 (has links)
This work is about diagrammatic languages, how they can be represented, and what they in turn can be used to represent. More specifically, it focuses on representations and applications of string diagrams. String diagrams are used to represent a collection of processes, depicted as "boxes" with multiple (typed) inputs and outputs, depicted as "wires". If we allow plugging input and output wires together, we can intuitively represent complex compositions of processes, formalised as morphisms in a monoidal category. While string diagrams are very intuitive, existing methods for defining them rigorously rely on topological notions that do not extend naturally to automated computation. The first major contribution of this dissertation is the introduction of a discretised version of a string diagram called a string graph. String graphs form a partial adhesive category, so they can be manipulated using double-pushout graph rewriting. Furthermore, we show how string graphs modulo a rewrite system can be used to construct free symmetric traced and compact closed categories on a monoidal signature. The second contribution is in the application of graphical languages to quantum information theory. We use a mixture of diagrammatic and algebraic techniques to prove a new classification result for strongly complementary observables. Namely, maximal sets of strongly complementary observables of dimension D must be of size no larger than 2, and are in 1-to-1 correspondence with the Abelian groups of order D. We also introduce a graphical language for multipartite entanglement and illustrate a simple graphical axiom that distinguishes the two maximally-entangled tripartite qubit states: GHZ and W. Notably, we illustrate how the algebraic structures induced by these operations correspond to the (partial) arithmetic operations of addition and multiplication on the complex projective line. The third contribution is a description of two software tools developed in part by the author to implement much of the theoretical content described here. The first tool is Quantomatic, a desktop application for building string graphs and graphical theories, as well as performing automated graph rewriting visually. The second is QuantoCoSy, which performs fully automated, model-driven theory creation using a procedure called conjecture synthesis.
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Neue Methoden zur Entdeckung von Fehlspezifikation bei Latent-Trait-Modellen der VeränderungsmessungKlein, Stefan 09 May 2003 (has links)
Ziel der Arbeit ist die Entwicklung von Modellen zur Entdeckung von Fehlspezifikation im Linear Logistic Test Model ( = LLTM) und verwandten Modellen der Verände\-rungs\-mes\-sung. Fehlspezifikation bedeutet hierbei, dass dem Modell ein unzutreffendes Muster latenter Traits zugrundegelegt wurde. Dies kann, vgl. z.B. [Baker,1993], zu bedeutenden Schätzfehlern führen. Die hier vorgestellten Methoden ermöglichen es unter leicht zu erfüllenden Annahmen, Aussagen über das Ausmaß der Unkorrektheit der verwendeten Modellspezifikation zu machen, ohne die in der Modellschätzung bestimmten Parameterwerte verwenden zu müssen. Zunächst wird eine auf dem Mantel-Haenszel-Test beruhende Methodik vorgestellt, die bei Tests bezüglich der Veränderungsparameter eines LLTMs als direkte Konkurrenz zu den bekannten Likelihood-Ratio-Tests für das LLTM anzusehen ist, wie sie z.B. bei [Fischer,1995a] vorgestellt werden. Weiterhin werden für das LLTM optimierte Personenfittests und daraus abgeleitete Effektgrößen vorgestellt. Diese ermöglichen das Auffinden von Subpopulationen, bei denen eine Abweichung zum angenommenen Modell aufgetreten ist. Es werden die statistischen Eigenschaften dieser Tests resp. Effektgrößen mittels Simulation und Teststärkeberechnung untersucht und Anwendungsbeispiele für diese Methoden vorgestellt. / In this thesis, new methods are developed for the detection of misspecification within Linear Logistic Test Models (=LLTM) and similar model classes for the measurement of change. The phrase "misspecification" will be used if a wrong selection of latent traits is chosen for the estimation of the LLTM. Misspecification can lead to erronious estimation [Baker,1993]). Using the newly developed methods, it is possible to measure the extent of deviations between the proposed model and the data. This can be done without using estimated parameter values. First a method is introduced which is based on the well-known Mantel-Haenszel-test. For some hypotheses, this method can be used instead of a Likelihood Ratio Test (e.g. [Fischer,1995a]). The Main topic of this thesis are uniformly most powerful tests for the measurement of person fit and related effect measures. These effect measures can be used for the identification of subpopulations where the proposed model does not hold. Statistical properties of these tests resp. effect measures are examined by simulations and power calculations using the SAS software. Furthermore, examples of the application of these methods are given.
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Uma abordagem de ensino-aprendizagem de programa??o na educa??o superiorSantana, Bianca Leite 06 April 2018 (has links)
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Previous issue date: 2018-04-06 / Funda??o de Amparo ? Pesquisa do Estado da Bahia - FAPEB / The proposed approach combines the use of the Scratch environment in a context of game creation, the Python programming language associated with the turtle graphics library, and image manipulation with the Jython Environment for Students (JES). We conducted two exploratory case studies with Civil Engineering students attending a CS1 course at our institution to analyze the impact of this approach on student motivation and learning. Our results describe the motivation present during the course in terms of the Attention, Relevance, Confidence and Satisfaction (ARCS) model, and identify the practical factors that may contribute to increase or decrease student motivation. We also present a framework that shows the positive and negative impacts of the elements of our approach on each of the categories of the ARCS model. Various such elements are common in several teaching-learning situations. From a learning point of view, our findings also show that contextualized and spiral learning has enhanced the learning of concepts such as loops and functions. Scratch facilitates the learning of programming logic, select and repeat structures. Python with Turtle enhances learning of these same concepts with the addition of functions. Finally, the media computation approach has shown potential for learning the concepts of functions and arrays. We believe that the practical factors presented in this work can support the design of CS1 courses for non-majors / Estudantes que n?o s?o da ?rea de TI, chamados non-majors , usualmente apresentam falta de interesse e maiores dificuldades na aprendizagem de programa??o em rela??o a estudantes de cursos como Ci?ncia da Computa??o. Neste trabalho descrevemos a concep??o, aplica??o e avalia??o de uma abordagem de ensino-aprendizagem de Programa??o, destinada a estudantes non-majors , cujo intuito ? aumentar a sua motiva??o e amenizar as suas dificuldades em aprender programa??o. A abordagem proposta combina o uso do ambiente l?dico Scratch em um contexto de cria??o de jogos, a linguagem de Programa??o Python associada ? biblioteca TurtleGraphics e ? manipula??o de imagens por meio do ambiente de desenvolvimento JythonEnvironment for Students (JES) . Realizamos dois estudos de caso explorat?rios com estudantes de Engenharia Civil cursando uma disciplina introdut?ria de programa??o em nossa institui??o para analisar o impacto desta abordagem sobre a motiva??o e aprendizagem dos estudantes. Nossos resultados descrevem a motiva??o presente durante o curso em termos do modelo Aten??o, Relev?ncia, Confian?a e Satisfa??o (ARCS), e identificam os fatores pr?ticos que podem contribuir para aumentar ou diminuir a motiva??o dos estudantes. Geramos um quadro que evidencia os impactos positivos e negativos dos elementos de nossa abordagem sobre cada uma das categorias do modelo ARCS, sendo que muitos destes elementos s?o comuns em diversas situa??es de ensino-aprendizagem. Do ponto de vista da aprendizagem, nossos achados demonstram que o ensino contextualizado e em espiral potencializou a aprendizagem de conceitos como loops e fun??es. Scratch potencializa a aprendizagem de l?gica de programa??o, loops e estruturas de sele??o. J? Python com Turtlepotencializa a aprendizagem destes mesmos conceitos com a adi??o de fun??es. Finalmente, a abordagem com m?dias demonstrou potencial para a aprendizagem dos conceitos de fun??es, vetores e matrizes. Acreditamos que os fatores pr?ticos apresentados nesse trabalho podem apoiar o design de disciplinas introdut?rias de programa??o para non-majors
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Desenvolvimento de métodos analíticos para a determinação de metais traço em vegetais da família Solanaceae por espectrometria de absorção atômica de alta resolução com fonte contínua em forno de grafite por análise direta de sólidos.Siqueira, Marianna Pozzatti Martins de January 2017 (has links)
Neste trabalho foram desenvolvidos quatro métodos analíticos para a determinação de cádmio, cromo, cobre, níquel e ferro em vegetais da família Solanaceae, cultivados pelos métodos convencional e orgânico de produção, obtidos em feiras e mercados da cidade de Porto Alegre, Brasil. Estes vegetais são muito consumidos devido a grande quantidade de nutrientes, no entanto, podem ser contaminados por elementos potencialmente tóxicos, por meio da exposição a poluição, uso de pesticidas, fertilizantes e água contaminada. As determinações foram conduzidas pela técnica de espectrometria de absorção atômica de alta resolução com fonte contínua em forno de grafite por análise direta de sólidos. Para Cd, Cr e Cu foram desenvolvidos três métodos independentes. No caso da determinação de Ni e Fe foi realizada análise simultânea, empregando linhas analíticas alternativas. Temperaturas de pirólise e atomização foram otimizadas para todos os elementos analisados, visando sinais analíticos com elevada sensibilidade e livres de interferências. Os métodos otimizados foram aplicados em amostras de pimentão, batata, tomate, berinjela, pimenta e physalis. Várias amostras apresentaram concentrações superiores aos limites máximos estabelecidos por legislações específicas. Os métodos propostos envolveram mínimo preparo de amostra, reduzindo riscos de contaminação, tempo analítico e custos, além de demonstrarem-se simples, precisos, rápidos e sensíveis. / In this work, four methods have been developed for the determination of cadmium, chromium, copper, nickel and iron in vegetables of the Solanaceae family, cultivated in conventional and organic farming systems, obtained from local markets and local farms, located in the city of Porto Alegre, Brazil. These vegetables are much appreciate due to the large amount of nutrients present in it. However, vegetables can be contaminated by potentially toxic elements, through the exposure to pollution, use of pesticide, fertilizers and contaminated water. The assays were carried out using a high-resolution continuum source graphite furnace atomic absorption spectrometer and direct solid sample analysis. Cd, Cr and Cu had their methods individually developed. In the case of the determination of Ni and Fe, it was applied simultaneous analysis, employing alternative analytical lines. Pyrolysis and atomization temperatures were optimized for all target elements, aiming for analytical signals with high sensitivity and free from interferences. The optimized methods were applied in samples of bell peppers, potato, tomato, eggplant, pepper and physalis. Several samples presented concentrations above the maximum permitted by specific legislation. The proposed methods were accurate, simple, fast and sensitive; moreover, a minimum sample preparation was necessary, reducing contamination, analytical time and costs.
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Reoxigenação superficial da água em canais abertos: o efeito da recirculação produzida por bombeamento / Surface reoxygenation of water in open channels: the effect of pumping produced recirculationPinheiro, Hemerson Donizete 26 August 2011 (has links)
O coeficiente de reaeração constitui-se no principal parâmetro usado em modelos de qualidade na avaliação preventiva do efeito da descarga de resíduos orgânicos sobre a concentração do oxigênio dissolvido (OD) em cursos de água naturais. Na literatura os valores observados para a concentração de saturação de OD em procedimentos experimentais para a determinação das taxas de reaeração superficial são, geralmente, reportados como inferiores aos valores calculados para as condições de temperatura, salinidade e pressão em que os experimentos foram realizados. Esse fato interfere significativamente na determinação do coeficiente de reaeração superficial, K2. Avalia-se neste trabalho a hipótese de que nessas situações a água é exposta a uma fonte de OD, que é a superfície em contato com a atmosfera, mas também a um sumidouro de OD, criado pelo próprio sistema de movimentação do fluido. O modelo matemático amplamente utilizado para estes fins não considera essa última possibilidade. Neste estudo foi comparada a eficácia deste modelo com um que considera a existência sumidouros do OD, o que justifica a baixa estimativa da concentração de saturação deste gás. Observou-se uma forte correlação entre a pressão na linha de sucção do sistema de recirculação e o valor do coeficiente de desoxigenação K*3 , que quantifica a intensidade do sumidouro. / The reaeration coefficient constitutes the main parameter used in models for the quality assessment of the preventive effect of the discharge of organic wastes on the concentration of dissolved oxygen (DO) in natural waterways. In the literature the values observed for the saturation concentration of DO in experimental procedures for determining the surface reaeration rates are generally reported as lower than the values calculated for the conditions of temperature, salinity and pressure at which the experiments were performed. This interferes significantly in the determination of surface reaeration coefficient, K2. In this work the following hypothesis is evaluated: that in these situations the water is exposed to a source of DO, which is the surface in contact with the atmosphere, as well as an DO sink, created by the pumping system. The mathematical model widely used does not consider this possibility. In this study the two kind of models were compared and the reasons for divergence were looked upon. There was a strong correlation between the pressure drop in the suction line of the recirculation system and a pseudo-coefficient of deoxygenation K*3 , which quantifies the sink intensity.
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Ion exchange to cope with decommissioningHerbas, Mélodie January 2018 (has links)
This PhD project studied the caesium and strontium removal capacities of six nanoporous materials. Indeed, it was linked in with the SIXEP plant present at Sellafield site, UK, which is currently using natural clinoptilolite, originally mined from the Mojave Desert, to remove radioactive caesium and strontium ions from wastewater effluents. At the moment the feeds entering the SIXEP plant correspond to the best working conditions for clinoptilolite. As the feeds are moving toward more acidic pH and complex solutions and as clinoptilolite works at neutral pH, new nanoporous materials are required. This project had been divided into sub-projects, which all had the same purpose of finding the best material for caesium and strontium removal under complex solutions. The first part of the PhD focused on the synthesis of CST, SNT, ETS-4 and ETS-10 materials following literature reviews. The two last materials studied were provided by Fortum Power and Heat Oy for CsTreat material and by Sellafield Ltd for clinoptilolite material. The second part of the PhD consisted in studying the exchange capacities for caesium and strontium ions for each material studied under batch conditions using several water compositions relevant to Sellafield Ltd. Each water composition had different competing ions or pH and were used to classify the materials between them. From that it was found that Clinoptilolite stays the best materials for caesium and strontium removal. The third part of the project was the gamma irradiation of the materials. This irradiation had an aim to check the stability of the structure of the studied materials under gamma irradiation. The materials were exposed to four different gamma doses which were 0.5; 1; 3 and 6 MGy, the last one corresponding to the maximum dose were structural changes could happen. This revealed that all the materials, except ETS-4 material, were stable under gamma irradiation and that no structural changes were observable. The fourth part of the project was an extension of the third part in which the materials were Cs exchanged before being gamma irradiated to a dose of 6 MGy. This showed that the caesium exchange process is not affected by radiation. Finally, the unexchanged materials were alpha irradiated using a 15 MeV He2+ beam at the Dalton Cumbria Facility. Two irradiations were performed on CsTreat, CST, ETS-4, ETS-10 and clinoptilolite material. It was found that all the materials were damaged by alpha irradiation and displayed amorphous framework To resume, it appeared that clinoptilolite still stays one of the best materials for the removal of caesium and strontium ions in a wide range of wastewater composition. Additionally, it was discovered that ETS-10 material could be a good alternative to clinoptilolite material as its structure is stable under gamma irradiation and it displayed good exchange capacities when competing ions were present in the feeds. CST could also be a substitute as it shows good ion exchange properties under a broad range of pH. SNT material was great for strontium removal while CsTreat was working well for caesium removal. Even though ETS- 4 revealed good ion exchange capacities they were lower than clinoptilolite, ETS- 10 or CST materials.
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Analog and Digital Approaches to UWB Narrowband Interference CancellationOmid, Abedi 02 October 2012 (has links)
Ultra wide band (UWB) is an extremely promising wireless technology for researchers and industrials. One of the most interesting is its high data rate and fading robustness due to selective frequency fading. However, beside such advantages, UWB system performance is highly affected by existing narrowband interference (NBI), undesired UWB signals and tone/multi-tone noises. For this reason, research about NBI cancellation is still a challenge to improve the system performance vs. receiver complexity, power consumption, linearity, etc. In this work, the two major receiver sections, i.e., analog (radiofrequency or RF) and digital (digital signal processing or DSP), were considered and new techniques proposed to reduce circuit complexity and power consumption, while improving signal parameters. In the RF section, different multiband UWB low-noise amplifier key design parameters were investigated like circuit configuration, input matching and desired/undesired frequency band filtering, highlighting the most suitable filtering package for efficient UWB NBI cancellation. In the DSP section, due to pulse transmitter signals, different issues like modulation type and level, pulse variety, shape and color noise/tone noise assumptions, were addressed for efficient NBI cancelation. A comparison was performed in terms of bit-error rate, signal-to-interference ratio, signal-to-noise ratio, and channel capacity to highlight the most suitable parameters for efficient DSP design. The optimum number of filters that allows the filter bandwidth to be reduced by following the required low sampling rate and thus improving the system bit error rate was also investigated.
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Indenyl-Metallkomplexe mit Metallen der Gruppe 4Weiß, Thomas 21 June 2001 (has links) (PDF)
Die vorliegende Arbeit beschreibt die Synthese, das Reaktionsverhalten und
die Charakterisierung von neuartigen in Position 2 silylsubstituierten
Indenylkomplexen mit Metallen der Gruppe 4 des Periodensystems der Elemente.
Insbesondere konnten silylenverbrückte Komplexe synthetisiert werden, in
welchen bislang unbekannte indenylhaltige ansa-Zirconocendichloride und
Halbsandwichmetalldichlorid-Komplexe mit rigidem Ligandengerüst verwirklicht
sind. Diese zeigen besondere Eigenschaften als Katalysatoren in der homogenen
Ziegler-Natta-(Co)Polymerisation von Ethen und Propen. Die einfache
Zugänglichkeit von 2-Indenylsilanen konnte durch eine Eintopfsynthese erreicht
werden, bei welcher ausgehend von 2-Bromindenen sehr gute Ausbeuten erreichbar
sind. Zur Synthese der 2-Bromindene wurden verschieden substituierte Indene
verwendet. Durch Variation des Substituentenmusters ist es möglich die
Eigenschaften des Katalysators gezielt zu beeinflussen. Die positionsabhängige
Aufklärung der Substituenteneigenschaften von Me und/oder SiMe3 im Indengerüst
nimmt daher einen bedeutenden Anteil dieser Arbeit ein. Zu diesem Zweck wurden
neuartige substituierte Indenyltitantrichloride präparativ zugänglich gemacht
und in Kombination mit bekannten Indenyltitantrichloriden mittels
UV/VIS-Spektroskopie und Cyclovoltammetrie untersucht. Auf der Basis des
gewonnenen Datenmaterials gelang es die Wirkung der Substituenten auf die
Grenzorbitale von Indenyltitantrichlorid zu modellieren. Unterstützt wurde das
Arbeitsmodell durch Extended-Hückel-Rechnungen, wobei die
Koeffizientenverteilung im p-System des Indenylliganden als
eigenschaftsbestimmend erkannt wurde. Indenyltitantrichloride ermöglichen
zudem den Zugang zu Verbindungen des Typs (h5-Ind)TiCl2-OR mit R = Aryl,
(h5-Ind)TiCl2 [(Ind) = C9H7, (1-SiMe3C9H6)]. Diese Komplexe zeigen auffällige
strukturelle Übereinstimmungen und Ähnlichkeiten mit verbrückten
ansa-Amidohalbsandwichtitandichloriden.
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Les concepts clés pour la réalisation d'un Holter intégré sur puceDing, Hao 13 October 2011 (has links) (PDF)
En dépit du développement rapide de la médecine, les maladies cardiovasculaires restent la première cause de mortalité dans le monde. En France, chaque année, plus de 50 000 personnes meurent subitement en raison d'arythmies cardiaques. L'identification des patients à risque élevé de décès soudain est toujours un défi. Pour détecter les arythmies cardiaques, actuellement Holter est généralement utilisé pour enregistrer les signaux électrocardiogramme (ECG) à 1~3 dérivations pendant 24h à 72h. Cependant l'utilisation de Holter est limitée parmi la population en raison de son encombrement (pas convivial) et de son coût. Un Holter mono puce portable nommé SoC-Holter qui permet d'enregistrer 1 à 4 dérivations est introduit. Le déploiement d'un réseau de capteurs sans fil exige que chaque SoC-Holter soit peu encombrant et peu cher, et consomme peu d'énergie. Afin de minimiser la consommation d'énergie et le coût du système, la technologie Complementary Metal Oxide Semiconductor (CMOS) (0.35μm) est utilisée pour la première implémentation de SoC-Holter. Puis une nouvelle méthode de détection basée sur Acquisition Comprimée (CS) est introduite pour résoudre les problèmes de consommation d'énergie et de capacité de stockage de SoC-Holter. Le principe premier de cette plate-forme est d'échantillonner les signaux ECG sous la fréquence de Nyquist 'sub-Nyquist' et par la suite de classer directement les mesures compressées en états normal et anormal. Minimiser le nombre de fils qui relient les électrodes à la plate-forme peut rendre l'utilisateur de SoC-Holter plus confortable, car deux électrodes sont très proches sur la surface du corps. La différence ECG enregistrée est analysée à l'aide de Vectocardiogramme (VCG). Les résultats expérimentaux montrent qu'une approche intégrée, à faible coût et de faible encombrement (SoC-Holter) est faisable. Le SoC-Holter consomme moins de 10mW en fonctionnement. L'estimation des paramètres du signal acquis est effectuée directement à partir de mesures compressées, éliminant ainsi l'étape de la reconstruction et réduisant la complexité et le volume des calculs. En outre, le système fournit les signaux ECG compressés sans perte d'information, de ce fait il réduit significativement la consommation d'énergie pour l'envoi de message et l'espace de stockage mémoire. L'effet de placement des électrodes est évalué sur la QRS complexe lorsqu'il a enregistré avec deux électrodes adjacentes. La méthode est basée sur l'algorithme de 'QRS-VCG loop alignment'. La méthode moindre carré est utilisée pour estimer la corrélation entre une boucle VCG observée et une boucle de référence en respectant les transformations de rotation et la synchronisation du temps. Les emplacements d'électrodes les moins sensibles aux interférences sont étudiés.
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Estratégias alternativas de preparo de amostras para a determinação de metais em alimentos por espectrometria de absorção atômica em chamaBrandão, Geovani Cardoso January 2011 (has links)
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Previous issue date: 2011 / CNPq / No presente trabalho, foram desenvolvidos métodos analíticos baseados em
estratégias alternativas de preparo de amostras para a determinação de metais em
alimentos por técnicas de espectrometria de absorção atômica com chama. No
primeiro método, a amostragem de suspensão foi usada para o preparo de amostras
de iogurte para a determinação de zinco por HR-CS FAAS. As condições
experimentais estabelecidas para o preparo das suspensões foram: solução de HCl
2,0 mol L-1, tempo de sonicação de 20 min e uma massa de amostra de 1,0 g.
Nestas condições, os limites de detecção e quantificação obtidos foram de 0,10 e
0,32 µg g-1, respectivamente. A precisão expressa como desvio padrão relativo
(RSD) foi de 0,82 e 2,08% para amostras contendo concentrações de zinco de 4,85
e 2,49 µg g-1, respectivamente. A exatidão do método foi confirmada pela análise de
material de referência certificado (CRM) de leite em pó desnatado NIST SRM 1549.
O método proposto foi aplicado para determinação de zinco em sete amostras de
iogurte. O teor de zinco variou de 2,19 a 4,85 µg g-1. No segundo método, a foto-
oxidação com radiação UV e H2O2 foi usada para o preparo de amostras de vinho
para a determinação de ferro e manganês por FS-FAAS. As condições
experimentais estabelecidas para a degradação das amostras de vinho foram:
volume de 2,5 mL de H2O2 30% (v/v), pH 10,0, concentração do tampão de 0,14 mol,
L-1 e um tempo de irradiação de 30 min. Nestas condições, foram obtidos limites de
detecção e quantificação de 0,030 e 0,099 µg mL-1 para ferro, e de 0,022 e 0,073 µg
mL-1 para manganês, respectivamente. A precisão expressa como RSD foi de 2,8 e
0,65% para ferro, e de 2,7 e 0,54% para manganês para concentrações de 0,5 e 2,0
µg mL-1, respectivamente. Teste de adição e recuperação usado para avaliar a
exatidão do método foi na faixa de 90 a 111% para ferro e na faixa de 95 a 107%
para manganês. O método proposto foi aplicado para a determinação de ferro e
manganês em seis amostras de vinho tinto. As concentrações obtidas variaram na
faixa de 1,58 a 4,45 µg mL-1 para ferro e na faixa de 1,30 a 1,91 µg mL-1 para
manganês. / Salvador
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