3 research outputs found

    Multimodalidades anodicas e catodicas : a negação controlada em logicas multimodais e seu poder expressivo

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    Orientador: Itala Maria Loffredo D'OttavianoTese (doutorado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciencias HumanasResumo: O presente trabalho tem por objetivo investigar o papel da negação no âmbito das modalidades, de forma a poder esclarecer até que ponto a negação pode ser atenuada, controlada ou mesmo totalmente eliminada em favor da melhor expressabilidade lógica de certas teorias, asserções ou raciocínios que sofrem os efeitos da negação. Contudo, atenuar ou eliminar a negação tem um alto preço: métodos tradicionais em lógica podem deixar de ser válidos e certos resultados, como teoremas de completude para sistemas lógicos, podem ser derrogados. Do ponto de vista formal, a questão central que investigamos aqui e até que ponto tais métodos podem ser restabelecidos. Com tal finalidade, iniciamos nosso estudo a partir do que denominamos sistemas anódicos" (sem negação) e, a posteriori, introduzimos gradativamente o elemento catódico" (negações, com diversas gradações e diferentes características) nos sistemas modais por meio de combinações com certas lógicas paraconsistentes, as chamadas lógicas da inconsistência formal (LFIs). Todos os sistemas tratados são semanticamente caracterizados por semânticas de mundos possíveis; resultados de incompletude são também obtidos e discutidos. Obtemos ainda semânticas modais de traduções possíveis para diversos desses sistemas. Avançamos na direção das multimodalidades, investigando os assim chamados sistemas multimodais anódicos e catódicos. Finalmente, procuramos avaliar criticamente o alcance e o interesse dos resultados obtidos na direção da racionalidade sensível à negação.Abstract: The present work aims to investigate the role of negations in the scope of modalities and in the reasoning expressed by modalities. The investigation starts from what we call anodic" systems (without any form of negation) and gradually reaches the cathodic" elements, where negations are introduced by means of combining modal logics with certain paraconsistent logics known as logics of formal inconsistency (LFIs). We obtain completeness results for all treated systems, and also show that certain incompleteness results can be obtained. The class of the investigated systems includes all normal modal logics that are extended by means of the schema Gk;l;m;n due to E. J. Lemmon and D. Scott combined with LFIs. We also tackle the question of obtaining modal possible-translations semantics for these systems. Analogous results are analyzed in the scope of multimodalities, where anodic as much as cathodic logics are studied. Finally, we advance a critical evaluation of the reach and scope of all the results obtained to what concerns expressibility of reasoning considered to be sensible to negation. We also critically assess the obtained results in contrast with problems of rationality that are sensible to negation.DoutoradoDoutor em Filosofi

    Analyzing the chemical heterogeneity of poly(dimethylsiloxanes) and other polymers: Development and optimization of a polymer HPLC method

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    Polymers are used versatile and ubiquitous as raw material for plastics, fibers, elastomers, rubbers, textiles, adhesives, and packaging. In this study, the determination of these materials with polymer liquid chromatographic techniques was applied, improved, and optimized. Beginning from the analysis of low and high molar mass poly(siloxanes) or silicones, the findings were also applied to various other polymers, e.g. poly(vinylchloride) or poly(methylmethacrylate). For low molar mass poly(dimethylsiloxanes) (PDMS), a baseline resolved separation of linear and cyclic oligomers up to 30 monomer units was developed and optimized by adapting mobile and stationary phases. For high molar mass PDMS (up to 250,000 g∙mol-1), a new saw tooth gradient design was invented, enabling high-resolution measurements. In addition to and as enhancement to size exclusion chromatography, the new high-resolution polymer HPLC (HRP-HPLC) allows the assignment of retention times to the corresponding molar masses in HPLC for single resolved peaks of (complex) polymer samples. The shape of the saw tooth gradient and further significant parameters as effective step length and height are optimized by Design of Experiments (DoE). Various other polymers, e.g. poly(vinylchloride), poly(styrene), poly(methylmethacrylate), and poly(propylene glycol) were investigated with HRP-HPLC by only adapting the stationary and mobile phase. Additionally, the performance of an evaporative light scattering detector (ELSD) was improved by implementing a new parallel-path poly(tetrafluoroethylene) nebulizer instead of the originally used concentric glass nebulizer. Thus, a significant improvement of the long-term stability and sensitivity was achieved for polymer analysis. Particularly, the invention, development, and optimization of the sawtooth gradient design results to a substantial improvement in (micro) structure elucidation of especially high molar mass polymers. Moreover, (semi) preparative fraction collection of various polymers enable the off- and online coupling to other powerful analytical techniques like MALDI mass spectrometry or NMR spectroscopy

    Thinking the (Im)possible

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