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O sistema de referência e contrarreferência em saúde bucal segundo a percepção de profissionais e usuários / The referral and counter referral system in oral health according to the perception of professionals and usersFernando de Castro Percebo 03 May 2016 (has links)
Os serviços oferecidos pelo Sistema Único de Saúde (SUS) estão organizados em rede, de forma a oferecer a seus usuários uma atenção integral. Com esse propósito, a configuração desta rede de serviços deve privilegiar o acesso do usuário ao nível de atenção que possa oferecer resolução ao seu caso, disponibilizando um adequado sistema de referência e contrarreferência para o usuário que necessite ser encaminhado de um nível de atenção a outro. Sendo assim, este estudo tem por objetivo avaliar a percepção dos profissionais e usuários referente ao sistema de referência e contrarreferência, e como este sistema funciona no cotidiano das unidades envolvidas neste estudo. Trata-se de um estudo qualitativo, cujos dados foram coletados através da aplicação de um questionário que visava obter as representações sociais de profissionais e usuários sobre o tema proposto, bem como alguns aspectos operacionais sobre o funcionamento deste sistema nestas unidades. Posteriormente os resultados foram apresentados e analisados na forma do Discurso do Sujeito Coletivo e permitiram concluir que profissionais e usuários têm a mesma percepção a respeito dos problemas que afetam o bom funcionamento deste sistema, tais como falta de profissionais, demora no atendimento, falta de resolutividade da atenção básica, disponibilidade de serviços na atenção secundária em desacordo com as necessidades da população, dificuldades na comunicação entre os profissionais dos diferentes níveis de atenção, e uma deficiência no controle do fluxo dos usuários, fazendo com que o sucesso dos encaminhamentos dependa muitas vezes do empenho pessoal dos profissionais e do esforço pessoal dos próprios pacientes. / The services offered by the Unified Health System (SUS) are organized in a network in order to offer its users an integral attention. For this purpose, the configuration of this services network should prioritize the users access to the health care level that can provide the solution to his case, and a suitable reference and counter reference system to the user that needs to be sent from a health care level to another. Thus, this study aims to evaluate the perception of professionals and users concerning the reference and counter reference system, and how this system works daily in the health units involved in this study. This is a qualitative study, where data were collected through the application of a questionnaire aimed to obtain the social representations of professionals and users about the proposed subject, as well as some operational aspects about the operation of this system at these health units. Subsequently the results were presented and analyzed in the form of Collective Subject Discourse and allow us to conclude that professionals and users have the same perception about the problems that affect the proper functioning of this system, such as lack of professionals, delay in treatment, lack of resoluteness of the primary health care, availability of services in secondary care at odds with people\'s needs, difficulties in communication between professionals of different health care levels, and a deficiency in controlling the flow of users, making the success of referrals dependent often on personal commitment of the professionals involved and of the patient\'s own efforts.
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Hoitamisen olemus:hoitotyön historiasta, teoriasta ja tulkinnasta hoitamista kuvaviin teoreettisiin väittämiinHaho, A. (Annu) 21 November 2006 (has links)
Abstract
The present study investigates phenomena of caring from the point of view of nursing work in the Western society, approaching the topic from historical and theoretical frames of reference.
The historical frame of reference is an entity where descriptions of the concepts and phenomena of nursing, nursing ethics and caring are explored from the point of view of hermeneutic interpretation of history. Data from an earlier period include publications, text books and research papers from the years 1903–1938 on nursing in Finland, nursing ethics and caring and also material on the life work of Ms. Naima Kurvinen (1876–1933), matron at the Oulu Province Hospital. Data from a later period consist of articles, literary work and research papers on nursing work, nursing ethics and caring from the years 1979–2004.
The theoretical frame of reference will here be approached from the points of view of phenomenology and philosophical hermeneutics. The data include philosophical literature on phenomenology, philosophical hermeneutics, and the essence, ethics and knowledge of humanity. Heidegger's philosophy of the mind of being proved to be a central theory in interpreting the phenomenon of caring.
Morality, autonomy and universality were the three theoretical statements of caring found in the study. Central characteristics describing the moral essence of caring were grouped under four theses as follows: 1. Moral statements describing caring are normative, i.e. they contain moral principles which guide our actions. The good of another individual emerged as the expressed function of caring. 2. Some values, such as humaneness, dignity, health, and well-being can intuitively be named as the good within caring. 3. The act of caring is to place oneself to take care of another person. This is based on freedom, authentic presence and ability to assume another person's preferences. The combination of these qualities describes altruism within caring. 4. The humane essence of man and interaction with others include ethical meanings of caring. Caring is action that protects, maintains and enriches life and involves hope.
The autonomous nature of caring is here described with the following three theses: 1. The autonomy of caring signifies the nurse's independence and the special nature of the context. Knowledge and the ability to place oneself to take care of another person are essential prerequisites. 2. The practical knowledge of caring is ethical in nature. 3. Prerequisites explaining caring, such as ethicality, knowledge, and awareness and meanings of nursing describe the phenomenological features of caring, making the act of caring an autonomous one.
The following two theses are used to argue for the universal essence of nursing: 1. Our humane and historical qualities are part of universally recognized humane values. Concern represents the manner of being within caring, describes meanings and values given to it and, finally, attaches one's awareness to the real world. 2. The moral of caring is universal in nature. / Tiivistelmä
Tarkastelen tässä tutkimuksessa hoitamisen ilmiötä länsimaisen hoitotyön näkökulmasta. Tutkimuksen lähestymistavaksi valitsin historiallisen ja teoreettisen viitekehyksen.
Historiallinen viitekehys on kokonaisuus, jossa hoitotyön, hoitoetiikan ja hoitamisen käsitteiden ja ilmiöiden kuvaukset muodostavat historiallisen aineiston, jota tarkastelen hermeneuttisen historiantulkinnan näkökulmasta. Varhaisempi aineisto sisältää suomalaista hoitotyötä, hoitoetiikkaa ja hoitamista käsitteleviä julkaisuja, oppikirjoja ja dokumentteja vuosilta 1903–1938 sekä Oulun lääninsairaalan ylihoitajatar Naima Kurvisen (1876–1933) elämäntyöhön liittyvän aineiston. Myöhäisempi aineisto koostuu hoitotyötä, hoitoetiikkaa ja hoitamista käsittelevistä artikkeleista, teoksista ja tutkimuksista vuosilta 1979–2004. Historiallinen viitekehys on opastanut minua hoitamisen alkuperäistä luonnetta esittävien kysymysten etsimisessä, tutkimuskohdetta kuvaavan aineiston löytämisessä ja sen hedelmällisessä tulkitsemisessa.
Teoreettisen viitekehyksen tarkastelunäkökulmiksi valitsin fenomenologian ja filosofisen hermeneutiikan. Aineisto sisältää fenomenologiaa ja filosofista hermeneutiikkaa sekä ihmisyyden olemusta, etiikkaa ja tietoa käsittelevää filosofista kirjallisuutta. Teoreettinen viitekehys mahdollisti tutkimuskulun ymmärtämisen sekä sen esittämisen. Heideggerin olemisen mielen filosofia osoittautui keskeiseksi teoriaksi hoitamisen ilmiön tulkitsemisessa.
Hoitamisen ensimmäisen väittämän, moraalisuuden, ominaispiirteet esitän seuraavissa teeseissä: 1. Hoitamista kuvaavat moraalilausumat ovat normatiivisia eli ne sisältävät toimintaa ohjaavia moraaliperiaatteita. Niissä ilmaistu hoitamisen funktio on toisen ihmisen hyvä. 2. Joitakin arvoja voidaan nimetä intuitiivisesti hoitamisen hyvän määritelmiksi. Näitä ovat inhimillisyys, arvokkuus, terveys ja hyvinvointi. 3. Hoitaminen on asettautumista toisen ihmisen hoitamiseen. Asettautumisen perustana on vapaus ja autenttinen läsnäolo sekä kyky toisen preferenssien omaksumiseen. Nämä ominaisuudet yhdessä kuvaavat altruismia hoitamisessa. 4. Ihmisen inhimillinen olemus ja kanssakäyminen toisten ihmisten kanssa sisältävät hoitamisen eettisyyden merkityksiä. Hoitaminen on elämää suojelevaa, ylläpitävää ja rikastavaa sekä toivoa sisältävää.
Toisen väittämän, autonomisuuden, olemusta kuvaavat ominaispiirteet esitän seuraavasti: 1. Hoitamisen autonomisuus tarkoittaa hoitajan itsenäisyyttä ja kontekstin erityislaatuisuutta. Tieto ja asettautuminen ovat sen välttämättömiä ehtoja. 2. Hoitamisen praktinen tieto on eettistä. 3. Hoitamista perustelevat ennakkoehdot, kuten eettisyys, tieto ja tiedostaminen sekä hoitamisen merkitykset, kuvaavat hoitamisen fenomenologisia ominaisuuksia. Nämä tekevät hoitamisesta autonomisen.
Hoitamisen universaalia olemusta perustelen kahden teesin avulla: 1. Ihmisen inhimilliset ja historialliset ominaisuudet kuuluvat yleismaailmallisesti esiintyviin humaanisiin arvoihin. Huoli ilmentää hoitamisen olemisen tapaa, kuvaa sille annettuja merkityksiä ja arvoja sekä kiinnittää tietoisuuden reaaliseen maailmaan. 2. Hoitamisen moraalin luonne on yleinen.
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Evaluation de la qualité des images couleur. Application à la recherche & à l'amélioration des images / Color image quality assessment application to retrieval and improve imagesOuni, Sonia 28 November 2012 (has links)
Le domaine de recherche dans l'évaluation objective de la qualité des images couleur a connu un regain d'intérêt ces dernières années. Les travaux sont essentiellement dictés par l'avènement des images numérique et par les nouveaux besoins en codage d'images (compression, transmission, restauration, indexation,…). Jusqu'à présent la meilleure évaluation reste visuelle (donc subjective) soit par des techniques psychophysiques soit par évaluation experte. Donc, il est utile, voire nécessaire, de mettre en place des critères et des mesures objectifs qui produisent automatiquement des notes de qualité se rapprochant le plus possible des notes de qualité données par l'évaluation subjective. Nous proposons, tout d'abort, une nouvelle métrique avec référence d'évaluation de la qualité des images couleur, nommée Delta E globale, se base sur l'aspect couleur et intègre les caractéristiques du système visuel humain (SVH). Les performances ont été mesurées dans deux domaines d'application la compression et la restauration. Les expérimentations réalisées montrent une corrélation importante entre les résultats obtenus et l'appréciation subjective. Ensuite, nous proposons une nouvelle approche d'évaluation sans référence de la qualité des images couleur en se basant sur les réseaux de neurones : compte tenu du caractère multidimensionnel de la qualité d'images, une quantification de la qualité a été proposée en se basant sur un ensemble d'attributs formant le descripteur PN (Précision, Naturalité). La précision traduit la netteté et la clarté. Quant à la naturalité, elle traduit la luminosité et la couleur. Pour modéliser le critère de la couleur, trois métriques sans référence ont été définies afin de détecter la couleur dominante dans l'image, la proportion de cette couleur et sa dispersion spatiale. Cette approche se base sur les réseaux de neurones afin d'imiter la perception du SVH. Deux variantes de cette approche ont été expérimentées (directe et progressive). Les résultats obtenus ont montré la performance de la variante progressive par rapport à la variante directe. L'application de l'approche proposée dans deux domaines : dans le contexte de la restauration, cette approche a servi comme un critère d'arrêt automatique pour les algorithmes de restauration. De plus, nous l'avons utilisé au sein d'un système d'estimation de la qualité d'images afin de détecter automatiquement le type de dégradation contenu dans une image. Dans le contexte de l'indexation et de la recherche d'images, l'approche proposée a servi d'introduire la qualité des images de la base comme index. Les résultats expérimentaux ont montré l'amélioration des performances du système de recherche d'images par le contenu en utilisant l'index qualité ou en réalisant un raffinement des résultats avec le critère de qualité. / The research area in the objective quality assessment of the color images has been a renewed interest in recent years. The work is primarily driven by the advent of digital pictures and additional needs in image coding (compression, transmission, recovery, indexing,...). So far the best evaluation is visual (hence subjective) or by psychophysical techniques or by expert evaluation. Therefore, it is useful, even necessary, to establish criteria and objectives that automatically measures quality scores closest possible quality scores given by the subjective evaluation. We propose, firstly, a new full reference metric to assess the quality of color images, called overall Delta E, based on color appearance and incorporates the features of the human visual system (HVS). Performance was measured in two areas of application compression and restoration. The experiments carried out show a significant correlation between the results and subjective assessment.Then, we propose a new no reference quality assessmenent color images approach based on neural networks: given the multidimensional nature of image quality, a quantification of quality has been proposed, based on a set of attributes forming the descriptor UN (Utility, Naturalness). Accuracy reflects the sharpness and clarity. As for naturality, it reflects the brightness and color. To model the criterion of color, three no reference metrics were defined to detect the dominant color in the image, the proportion of that color and its spatial dispersion. This approach is based on neural networks to mimic the HVS perception. Two variants of this approach have been tried (direct and progressive). The results showed the performance of the progressive variant compared to the direct variant. The application of the proposed approach in two areas: in the context of restoration, this approach has served as a stopping criterion for automatic restoration algorithms. In addition, we have used in a system for estimating the quality of images to automatically detect the type of content in an image degradation. In the context of indexing and image retrieval, the proposed approach was used to introduce the quality of images in the database as an index. The experimental results showed the improvement of system performance image search by content by using the index or by making a quality refinement results with the quality criterion.
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Univerzální napájecí zdroj s mikrokontrolérem / General-purpose power supply with microcontrollerJorda, Ivo January 2014 (has links)
The aim of this thesis is design of adjustable switched mode power supply with symmetrical output of 25 V, and switched mode power supply with fixed output voltage of 5 V. Required maximum output current of each outputs is 3 A. At the beginning of the paper function of the basic SMPS topologies is described. Next all reqiured SMPSs are designed and chosen parts of the design are simulated. In the second half of the thesis assembly and testing of PCB are described as well as functions of programs. Last chapter contains results of meassurement of power supply paramters.
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Návrh převodníku DA s plně diferenčním výstupem v technologii CMOS / Design of DA converter with fully differential output in CMOS technologyMácha, Petr January 2017 (has links)
This diploma thesis deals with the design of eight-bit digital to analog coverter with fully differential outputs in technology I3T25 of ON Semiconductor company. The work contains the description of basic structures and characteristics of digital to analog converters. The main focus of the work is to design a converter and auxiliary circuits at the transistor level. The functionality of designed circuits is verified by simulation environment Cadence.
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Reference Architectures as Means to Aid in System DevelopmentZeito, Maurice January 2013 (has links)
In comparison with the ever increasing development of enterprise architectures and frameworks, reference architectures has yet to reach the same maturity level. This brings questions regarding definition, implementation and governance of reference architectures at different levels; Business, System, Technical. In this report, an in-depth analysis of the concept of reference architctures is made, focusing on the abovementioned attributes. The purpose of the report is to provide the reader with an insight on how reference architectures can be implemented in order to aid in the work of system development.
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Aplikace chatu ve virtuálních referenčních službách / Chat application in the virtual reference servicesŠevčíková, Veronika January 2011 (has links)
The aim of this thesis is to describe of the chat application in the virtual reference services from both theoretical and practical point of view. The theoretical part is based on close reading of the mostly foreign literature. The first introductory chapter discusses the terminology and definition of reference services and then virtual reference services, which have not been settled yet. The second chapter deals with chat application. All phases of the chat application are mentioned, from planning through implementation and marketing to the final evaluation of the service. The third chapter is devoted to chat as a specific form of communication with particular focus on its advantages and disadvantages in the library services. The findings of these chapters are used in the analysis of the chosen virtual reference services. The practical part in the fourth chapter constitutes chat in real use, first in foreign libraries, then in Czech libraries as well. The fifth chapter constitutes the main contribution of the practical part. It describes the chat preparation within the Czech cooperative virtual reference service "Ask your library" in the National Library of the Czech Republic, in which the autor of this thesis participated. The conclusion provides a brief summary.
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Linked Bernoulli Synopses: Sampling along Foreign KeysGemulla, Rainer, Rösch, Philipp, Lehner, Wolfgang 12 January 2023 (has links)
Random sampling is a popular technique for providing fast approximate query answers, especially in data warehouse environments. Compared to other types of synopses, random sampling bears the advantage of retaining the dataset’s dimensionality; it also associates probabilistic error bounds with the query results. Most of the available sampling techniques focus on table-level sampling, that is, they produce a sample of only a single database table. Queries that contain joins over multiple tables cannot be answered with such samples because join results on random samples are often small and skewed. On the contrary, schema-level sampling techniques by design support queries containing joins. In this paper, we introduce Linked Bernoulli Synopses, a schema-level sampling scheme based upon the well-known Join Synopses. Both schemes rely on the idea of maintaining foreign-key integrity in the synopses; they are therefore suited to process queries containing arbitrary foreign-key joins. In contrast to Join Synopses, however, Linked Bernoulli Synopses correlate the sampling processes of the different tables in the database so as to minimize the space overhead, without destroying the uniformity of the individual samples. We also discuss how to compute Linked Bernoulli Synopses which maximize the effective sampling fraction for a given memory budget. The computation of the optimum solution is often computationally prohibitive so that approximate solutions are needed. We propose a simple heuristic approach which is fast and seems to produce close-to-optimum results in practice. We conclude the paper with an evaluation of our methods on both synthetic and real-world datasets.
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Characterisation of proton exchange membranes in an H₂SO₄ environment / Retha PeachPeach, Retha January 2014 (has links)
In light of the world‟s growing demand for energy that is environmentally friendly and sustainable, energy sources such as hydrogen have been considered potential contenders. Hydrogen, which can be used for energy storage, can be produced efficiently by the membrane based Hybrid Sulfur (HyS) thermo-chemical process consisting of a decomposition and an electrolysis step. During the HyS electrolysis step, SO2 and H2O are converted to H2 and H2SO4, which implies that the proton exchange membranes (PEMs) to be used for this process should have a high proton conductivity, limited SO2 cross-over and good H2SO4 stability.
In order to find alternatives to the costly and high-temperature unstable Nafion®, the aim of this study was to evaluate the H2SO4 stability of various novel membranes. To structure the study, the novel PEM materials were grouped according to the PBI-type base component within the blend membranes, resulting in three groups comprising non-PBI based membranes, PBIOO based membranes and F6-PBI based membranes. Nafion®212 was included as reference PEM. By repeating the H2SO4 treatment with three different Nafion®212 samples, the obtained Nafion® data was also used to determine the experimental and analytical error margins for the study. The stability of all membranes was determined by submerging the membrane samples in 80 wt% H2SO4 at 80 °C for 120 hours. To determine the influence of the acid on the membranes, all samples were characterised before and after the H2SO4 treatment and compared in terms of their acid stability. Physical characterisation of the PEMs included the evaluation of weight and thickness changes, while IEC, SEM-EDX, FTIR and TGA were used to elucidate possible chemical changes due to the H2SO4 treatment.
According to the Nafion®212 data, which had been obtained in triplicate for each of the analytical techniques, the experimental error of both the analytical and H2SO4 treatment remained below 10 %, except for the SEM-EDX sulfur-content where significantly larger errors were observed. In spite of the high error margins of the SEM-EDX data (S-content), its results, combined with the results from the other analytical techniques, resulted in a better understanding (both physical and chemical) of the effect the H2SO4 had on the membrane. This further facilitated the evaluation and comparison of the various blended PEM materials in terms of their H2SO4 stability, and the subsequent relation obtained between the observed stability and the chemical constitution and cross-linking of the membranes.
After the 80 wt% H2SO4 treatment, significant weight losses were reported for the non-PBI based and PBIOO based membrane groups in comparison with the minimal changes noted for the F6-PBI based group and Nafion®212. Furthermore, significant thickness changes were
reported for most of the PBIOO based membranes. The small weight and thickness changes observed for the F6-PBI confirmed the improved stability of this group of membranes in an H2SO4 environment, most likely due to the protective role of the partially fluorinated basic polymer and the known strength of the C-F bonds present.
The results showed a clear correlation between the H2SO4 stability and the specific polymers present in the PEM blends investigated. Specific effects found included sulfonation, salt formation, hydrolysis and the accompanied dissolution of membrane fragments. Significant physical changes, for example ascribed to sulfonation of the concerned polymers, were supported by increased IEC measurements and peak intensities of the FTIR spectra, corresponding to the additional –SO3H groups present, while a variation in TGA signals served to further support the altered membrane composition and structure due to the H2SO4 treatment. In the case of dissolution, the corresponding chemical changes (analytical techniques) were supported by the decreased peak intensities of FTIR spectra, IEC measurements and TGA signals associated with degradation of the polymer backbone.
It was shown that the stability of the blended membranes depended on the composition (blend components) of the membrane and the effective cross-linking (interaction) between the blend components. For all three groups examined, it became apparent that blend components sFS and sPSU were, for example, more stable than sPEEK and that ionical cross-linking seemed more effective than covalent cross-linking of blend components.
When considering all membranes tested, the non-PBI based blend membranes consisting of (s)PSU and PFS copolymers in the presence of fluorinated cross-linkers and the PBIOO-sPSU blended membranes including most of the F6-PBI based membranes showed sufficient stability to be recommended for SO2 electrolysis. / MSc (Chemistry), North-West University, Potchefstroom Campus, 2014
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Characterisation of proton exchange membranes in an H₂SO₄ environment / Retha PeachPeach, Retha January 2014 (has links)
In light of the world‟s growing demand for energy that is environmentally friendly and sustainable, energy sources such as hydrogen have been considered potential contenders. Hydrogen, which can be used for energy storage, can be produced efficiently by the membrane based Hybrid Sulfur (HyS) thermo-chemical process consisting of a decomposition and an electrolysis step. During the HyS electrolysis step, SO2 and H2O are converted to H2 and H2SO4, which implies that the proton exchange membranes (PEMs) to be used for this process should have a high proton conductivity, limited SO2 cross-over and good H2SO4 stability.
In order to find alternatives to the costly and high-temperature unstable Nafion®, the aim of this study was to evaluate the H2SO4 stability of various novel membranes. To structure the study, the novel PEM materials were grouped according to the PBI-type base component within the blend membranes, resulting in three groups comprising non-PBI based membranes, PBIOO based membranes and F6-PBI based membranes. Nafion®212 was included as reference PEM. By repeating the H2SO4 treatment with three different Nafion®212 samples, the obtained Nafion® data was also used to determine the experimental and analytical error margins for the study. The stability of all membranes was determined by submerging the membrane samples in 80 wt% H2SO4 at 80 °C for 120 hours. To determine the influence of the acid on the membranes, all samples were characterised before and after the H2SO4 treatment and compared in terms of their acid stability. Physical characterisation of the PEMs included the evaluation of weight and thickness changes, while IEC, SEM-EDX, FTIR and TGA were used to elucidate possible chemical changes due to the H2SO4 treatment.
According to the Nafion®212 data, which had been obtained in triplicate for each of the analytical techniques, the experimental error of both the analytical and H2SO4 treatment remained below 10 %, except for the SEM-EDX sulfur-content where significantly larger errors were observed. In spite of the high error margins of the SEM-EDX data (S-content), its results, combined with the results from the other analytical techniques, resulted in a better understanding (both physical and chemical) of the effect the H2SO4 had on the membrane. This further facilitated the evaluation and comparison of the various blended PEM materials in terms of their H2SO4 stability, and the subsequent relation obtained between the observed stability and the chemical constitution and cross-linking of the membranes.
After the 80 wt% H2SO4 treatment, significant weight losses were reported for the non-PBI based and PBIOO based membrane groups in comparison with the minimal changes noted for the F6-PBI based group and Nafion®212. Furthermore, significant thickness changes were
reported for most of the PBIOO based membranes. The small weight and thickness changes observed for the F6-PBI confirmed the improved stability of this group of membranes in an H2SO4 environment, most likely due to the protective role of the partially fluorinated basic polymer and the known strength of the C-F bonds present.
The results showed a clear correlation between the H2SO4 stability and the specific polymers present in the PEM blends investigated. Specific effects found included sulfonation, salt formation, hydrolysis and the accompanied dissolution of membrane fragments. Significant physical changes, for example ascribed to sulfonation of the concerned polymers, were supported by increased IEC measurements and peak intensities of the FTIR spectra, corresponding to the additional –SO3H groups present, while a variation in TGA signals served to further support the altered membrane composition and structure due to the H2SO4 treatment. In the case of dissolution, the corresponding chemical changes (analytical techniques) were supported by the decreased peak intensities of FTIR spectra, IEC measurements and TGA signals associated with degradation of the polymer backbone.
It was shown that the stability of the blended membranes depended on the composition (blend components) of the membrane and the effective cross-linking (interaction) between the blend components. For all three groups examined, it became apparent that blend components sFS and sPSU were, for example, more stable than sPEEK and that ionical cross-linking seemed more effective than covalent cross-linking of blend components.
When considering all membranes tested, the non-PBI based blend membranes consisting of (s)PSU and PFS copolymers in the presence of fluorinated cross-linkers and the PBIOO-sPSU blended membranes including most of the F6-PBI based membranes showed sufficient stability to be recommended for SO2 electrolysis. / MSc (Chemistry), North-West University, Potchefstroom Campus, 2014
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