181 resultados para FIA-CVAAS


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A flow-injection system with a Chelite-S® cationic resin packed minicolumn is proposed for the determination of trace levels of mercury in agroindustrial samples by cold vapor atomic absorption spectrometry. Improved sensitivity and selectivity are attained since mercuric ions are on-line concentrated whereas other potential interferents are discarded. With on-line reductive elution procedure, concentrated hydrochloric acid could be replaced by 10% w/v SnCl2, in 6 M HCl as eluent. The reversed-intermittent stream either carries the atomic mercury, to the flow cell in the forward direction or removes the residue from reactor/gas liquid separator to a discarding flask in the opposite direction. Concentration and volume of reagent, acidity, flow rates, commutation times and potential interfering species were investigated. For 120 s preconcentration time, the proposed system handles about 25 samples h-1 (50.0 500 ng l-1), consuming about 10 ml sample and 5 mg SnCl2 per determination. The detection limit is 0.8 ng l-1 and the relative standard deviation (RSD) (n = 12) of a 76.7 ng l-1 sample is about 5%. Results are in agreement with certified value of standard materials at 95% confidence level and good recoveries (97-128%) of spiked samples were found. (C) 2000 Elsevier Science B.V.

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The leaves of Myrcia DC. ex Guill species are used in traditional medicine and are also exploited commercially as herbal drugs for the treatment of diabetes mellitus. The present work aimed to assess the qualitative and quantitative profiles of M. bella hydroalcoholic extract, due to these uses, since the existing legislation in Brazil determines that a standard method must be developed in order to be used for quality control of raw plant materials. The current study identified eleven known flavonoid-O-glycosides and six acylated flavonoid derivatives of myricetin and quercetin, together with two kaempferol glycosides and phenolic acids such as caffeic acid, ethil galate, gallic acid and quinic acid. In total, 24 constituents were characterized, by means of extensive preparative chromatographic analyses, along with MS and NMR techniques. An HPLC-PAD-ESI-ITMS and FIA-ESI-IT-MSn method were developed for rapid identification of acylated flavonoids, flavonoid-O- glycosides derivatives of myricetin and quercetin and phenolic acids in the hydroalcoholic M. bella leaves extract. The FIA-ESI-IT-MS techinique is a powerful tool for direct and rapid identification of the constituents after isolation and NMR characterization. Thus, it could be used as an initial method for identification of authentic samples concerning quality control of Myrcia spp extracts. © 2013 by the authors.

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Pós-graduação em Química - IQ

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Abstract Background Measurements of hormonal concentrations by immunoassays using fluorescent tracer substance (Eu3+) are susceptible to the action of chemical agents that may cause alterations in its original structure. Our goal was to verify the effect of two types of anticoagulants in the hormone assays performed by fluorometric (FIA) or immunofluorometric (IFMA) methods. Methods Blood samples were obtained from 30 outpatients and were drawn in EDTA, sodium citrate, and serum separation Vacutainer®Blood Collection Tubes. Samples were analyzed in automatized equipment AutoDelfia™ (Perkin Elmer Brazil, Wallac, Finland) for the following hormones: Luteinizing hormone (LH), Follicle stimulating homone (FSH), prolactin (PRL), growth hormone (GH), Sex hormone binding globulin (SHBG), thyroid stimulating hormone (TSH), insulin, C peptide, total T3, total T4, free T4, estradiol, progesterone, testosterone, and cortisol. Statistical analysis was carried out by Kruskal-Wallis method and Dunn's test. Results No significant differences were seen between samples for LH, FSH, PRL and free T4. Results from GH, TSH, insulin, C peptide, SHBG, total T3, total T4, estradiol, testosterone, cortisol, and progesterone were significant different between serum and EDTA-treated samples groups. Differences were also identified between serum and sodium citrate-treated samples in the analysis for TSH, insulin, total T3, estradiol, testosterone and progesterone. Conclusions We conclude that the hormonal analysis carried through by FIA or IFMA are susceptible to the effects of anticoagulants in the biological material collected that vary depending on the type of assay.

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The aim of this dissertation is to provide a trilingual translation from English into Italian and from Italian into Spanish of a policy statement from the Fédération Internationale de l’Automobile (FIA) regarding road safety. The document, named “Formula Zero: a strategy for reducing fatalities and injuries on track and road”, was published in June 2000 and involves an approach about road safety inspired by another approach introduced in Sweden called ‘Vision Zero’. This work consists of six sections. The first chapter introduces the main purposes and activities of the Federation, as well as the institutions related to it and Vision Zero. The second chapter presents the main lexical, morphosyntactic and stylistic features of the institutional texts and special languages. In particular, the text contains technical nomenclature of transports and elements of sport language, especially regarding motor sport and Formula One. In the third chapter, the methodology is explained, with all the resources used during the preliminary phase and the translation, including corpora, glossaries, expert consultancy and specialised sites. The fourth chapter focuses on the morphosyntactic and terminology features contained in the text, while the fifth chapter presents the source text and the target texts. The final chapter deals with all the translation strategies that are applied, alongside with all the challenging elements detected. Therefore, the dissertation concludes with some theoretical and practical considerations about the role of inverse translation and English as Lingua Franca (ELF), by comparing the text translated into Spanish to the original in English, using Italian as a lingua franca.

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Julie Wolfthorn

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Mode of access: Internet.

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In this study, we examine how organisations in Fiji communicate or legitimise their profit. We base the need for understanding this phenomenon on the following premise. Organisations are part of a wider society, and in competition for scarce resources. Organisations obtain the rights to consume resources upon conception, but must continually legitimise their rights of existence and the need to access the resources. Legitimacy is the ability to continue to justify one’s authority to exist in a society. Organisations rights to resources are contractual, and have a moral obligation to act in a responsible manner and justify their outcomes, actions, and activities to external stakeholders. Such justifications would be an attempt at legitimizing their existence by some form of impression management. Impression management refers to the process by which individuals attempt to influence the impression of others (Melo et al. 2009). In corporate reporting, impression management occurs when management selects, display, and presents that information in a manner that distorts readers’ perceptions of corporate achievements (Neu 1991; Patten 2002), and is managed best through disclosures (O’Donovan 2002). In developing economies, there is significant Government protection that creates near-monopoly sectors and industries. The rendered protection permits organisations to provide essential services to the community at reasonable costs. Organisations in these sectors and industries have an ominous need to legitimise their position and actions. The bond between the organisations and the society is much stronger, making organisations devote more effort in communicating their activities. Protection permits organisations to make reasonable profits to sustain their operations. Society may not accept abnormal profits from operational efficiencies. Profit is fundamental to the society’s perception of an organisation, amplifying the need for the firm to justify a level of profit. Abnormal profit for organisations construes bad news, and organisations would make relevant disclosures to manage stakeholder impressions on profit (Patten 2002). Organisations can manage impressions by disclosing information in a particular way. That is, organisations would want to put the impression that the abnormal profit is justified and the society will obtain its benefits in future. Such form of impression management requires unambiguous disclosure of information. The readability of corporate disclosures is an important indicator of organisational abnormal profit-related legitimacy efforts in developing economies.

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The IT systems drive the financial reporting processes in modern business environments. The result is an integrative system of initialing, authorizing, recording, and processing of financial transactions. This IT-related change inextricably links to the overall financial reporting process, requiring a deeper level of understanding and commitment. Firm’s IT governance initiatives provide this commitment by enforcing controls to IT components to ensure compliance to overall financial reporting requirements. The IT governance institute (ITGI) and other authorities have developed a number of frameworks and guidelines (e.g., COBIT) to help management in managing IT-intensive processes.

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There has never been a better time to strengthen financial reporting in Fiji. With increased interest shown by prospective companies in capital market participation, the pressing problems in the public sector reporting and accountability and global emphasis on the increasing need to strengthen the corporate governance structure, this is perhaps the opportune time to consider the potential of XBRL.

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There is no doubt that information technology (IT) resources are important for organisations in any jurisdiction to manage their processes. Organisations consume considerable financial resources to acquire and manage their IT resources with various IT governance structures. Investment in IT, thus, is a strategic necessity. IT resources, however, do not contribute fully to business value on their own. Business value considers performance impacts of resources at various organisational levels (e.g., processes and firm levels). ITs are biased resources in that they require some form of manipulation to attain their maximum value. While we know that IT resources are important, a deeper understanding on two aspects of use of IT resources in organisations is important. First, is how to leverage the IT resources to attain its maximum value, and second, is where to evaluate IT-related business value in the organisation’s value chain. This understanding is important for organisation to sustain their operations in an ever-changing business environment. We address these issues in two parts. This paper discusses the first aspect of ways in which organisations can create and sustain their IT-related business value.