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<p>The boundaries of science fiction, as with any genre, are relational rather than fixed, and critical engagements with Western/Northern technoscientific knowledge and practice and modern human identity and being may be found not just in science fiction “proper,” or in the scholarly field of science and technology studies, but also in the related genres of fantasy and paranormal romance. This thesis offers an interdisciplinary examination – a science-fictional and posthumanist reframing – of the lines of affinity and relationality between these discursive and imaginative domains. Bringing together genre theory and critical posthumanism – itself informed by postmodern and poststructuralist feminism, postcolonialism, science and technology studies, and critical animal studies – with readings of several series in print (Christine Feehan’s Ghostwalkers, Kim Harrison’s The Hollows, and Justina Robson’s Quantum Gravity) and on television (Fringe, True Blood, and Sanctuary), I argue that such narratives’ powerful abiding interest in the domains of knowledge, experience and imagination that lie within, along and outside the margins of scientific orthodoxy, registers a broader cultural apprehension of the conditions and critical perspectives by which Western/Northern humanism, anthropocentrism, modernity, and technoscientific authority have been and can be seen to be destabilized.</p> / Doctor of Philosophy (PhD)

[ES] Los Nanotubos (CNTs) y Nanofibras de Carbono (CNFs) son materiales de nueva generación que tienen características mejores que los materiales convencionalmente utilizados. Los Nanotubos están formados por carbono, siendo su unidad elemental un plano de grafito enrollado cilíndricamente creando tubos de diámetro nanométrico. Por otro lado, las Nanofibras son materiales intermedios entre las habituales fibras de carbono y los CNTs, las cuales se han desarrollado con la finalidad de obtener fibras de carbono nanométricas y pudiendo reemplazar a los CNTs, de una forma más económica y pudiéndose obtener en grandes cantidades. Todo ello, ha llevado a que estos materiales susciten grandes intereses como consecuencia de sus variadas aplicaciones posibles, provocando que se haya trabajado en optimizar y trasladar su proceso de producción a nivel industrial y cada día sean más atractivos. La conveniencia de utilizar estos productos radica en sus excelentes propiedades mecánicas, alta conductividad térmica y eléctrica, así como buena estabilidad a altas temperaturas. Todo ello hace que este tipo de materiales sea muy interesante para ser empleado como refuerzo en matrices termoplásticas. Sin embargo, los materiales compuestos que se ha conseguido obtener hasta la fecha presentan unas propiedades muy inferiores a las inicialmente esperadas, debido a la naturaleza de los materiales y la elevada incompatibilidad existente entre la matriz polimérica y el nano-refuerzo. Ésta provoca la aglomeración de las partículas y la formación de una interfase polímeronanopartícula de malas propiedades mecánicas, donde la transferencia de tensión entre la matriz y el refuerzo no es efectiva. En busca de alternativas a esta problemática, el presente trabajo trata de evaluar como evolucionas distintas propiedades, como las mecánicas, térmicas, reológicas y/o eléctricas, en los materiales desarrollados tras la incorporación de distintas cantidades tanto de CNFs como de CNTs a una matriz de Polipropileno, mediante un proceso de mezclado en fundido o compounding. En un último estudio, se ha analizado cómo evolucionan las propiedades eléctricas o antiestáticas de estos materiales al ser sometidos a subsiguientes procesados con aportes térmicos (Tª) como son la extrusión de monofilamento y la posterior impresión 3D del mismo, para transformarse en una pieza final. / [CA] Els Nanotubs (CNTs) i Nanofibres de Carboni (CNFs) són una nova generació de materials que presenten unes propietats superiors als materials convencionalment utilitzats. Els CNTs són uns materials formats per carboni, on la unitat bàsica és un pla grafític enrotllat que forma un cilindre, formant uns tubs el diàmetre dels quals és de l'ordre d'alguns nanòmetres. Les CNFs per part seua, es consideren com a materials intermedis entre les fibres de carboni convencionals i els CNTs, desenvolupades a fi de produir unes fibres de carboni de grandària nanométrica alternatives als nanotubs, més econòmiques i amb la possibilitat de ser produïdes en grans volums. Tot això, ha portat al fet que aquests materials susciten grans interessos a causa de les seues múltiples possibles aplicacions, provocant que s'haja treballat a optimitzar i traslladar el seu procés de producció a nivell industrial i cada dia siguen més atractius. La conveniència d'utilitzar aquests productes radica en les seues excel·lents propietats mecàniques, alta conductivitat tèrmica i elèctrica, així com bona estabilitat a altes temperatures. Tot això fa que aquest tipus de materials siga molt interessant per a ser emprat com a reforç en matrius termoplàstiques. No obstant això, els materials compostos que s'ha aconseguit obtindre fins hui presenten unes propietats molt inferiors a les inicialment esperades, a causa de la naturalesa dels materials i l'elevada incompatibilitat existent entre la matriu polimèrica i el nano-reforç. Aquesta provoca l'aglomeració de les partícules i la formació d'una interfase polímer-nanopartícula de baixes propietats mecàniques, on la transferència de tensió entre la matriu i el reforç no és efectiva. A la recerca d'alternatives a aquesta problemàtica, el present treball tracta d'avaluar com evoluciones diferents propietats, com les mecàniques, tèrmiques, reològiques i/o elèctriques, en els materials desenvolupats després de la incorporació de diferents quantitats tant de CNFs com de CNTs a una matriu de Polipropilè, mitjançant un procés de barrejat en fos o compounding. En un últim estudi, s'ha analitzat com evolucionen les propietats elèctriques o antiestàtiques d'aquests materials en ser sotmesos a subsegüents processaments amb aportacions tèrmiques (Tª) com són l'extrusió de monofilaments i la posterior impressió 3D d'aquest, per a transformar-se en una peça final. / [EN] Nanotubes (CNTs) and Carbon Nanofibers (CNFs) are a new generation of materials that present superior properties to conventionally used materials. CNTs are materials made of carbon, where the basic unit is a rolled graphite plane that forms a cylinder, forming tubes whose diameter is of the order of a few nanometres. For their part, CNFs are considered as intermediate materials between conventional carbon fibres and CNTs, developed in order to produce nano-sized carbon fibres that are alternatives to nanotubes, cheaper and with the possibility of being produced in large volumes. . All this has led to these materials arousing great interest due to their multiple possible applications, causing work to be done to optimize and transfer their production process to an industrial level and become more attractive every day. The convenience of using these products lies in their excellent mechanical properties, high thermal and electrical conductivity, as well as good stability at high temperatures. All this makes this type of material very interesting to be used as reinforcement in thermoplastic matrices. However, the composite materials that have been obtained to date have much lower properties than those initially expected, due to the nature of the materials and the high incompatibility between the polymeric matrix and the nanoreinforcement. This causes the agglomeration of the particles and the formation of a polymer-nanoparticle interface with poor mechanical properties, where the transfer of tension between the matrix and the reinforcement is not effective. In search of alternatives to this problem, this work tries to evaluate how different properties evolve, such as mechanical, thermal, rheological and / or electrical, in the materials developed after the incorporation of different amounts of both CNFs and CNTs to a matrix. Polypropylene, through a melt mixing process or compounding. In a last study, it has been analysed how the electrical or antistatic properties of these materials evolve when subjected to subsequent processing with thermal inputs (Tª) such as the extrusion of monofilament and the subsequent 3D printing of it, to become a final piece . / Peris Abad, F. (2021). Desarrollo de materiales compuestos mediante la modificación de matrices de polipropileno por adición de nanofibras de carbono y nanotubos de carbono para su utilización en el sector textil [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/165209

Die vorliegende Arbeit handelt von der Erforschung und Entwicklung von gedruckten stromführenden Leitern auf dreidimensionalen Objekten, die mit robotergeführten Inkjet-Druck- und Dosierverfahren hergestellt werden. Im Fokus stehen dabei Forschungen, die von den drucktechnischen Grundlagen bis hin zur Demonstration der Technologie und deren Realisierbarkeit anhand konkreter Anwendungsbeispiele reichen. Dabei wird die Entwicklung eines Roboterversuchsstands und einer Vorgehensweise (Workflow) beschrieben, mit denen es möglich ist, Leiterzüge direkt auf 3D-Objekte zu drucken. Die systematische Untersuchung und Optimierung der Technologie und des Prozesses stellt ein Novum dar und ist von großem Interesse für verschiedene Industriezweige wie der Automobil-, Luftfahrt- und Elektronikindustrie. Im Rahmen grundlegender Experimente werden zunächst die digitalen Drucktechnologien Inkjet und Dispensing hinsichtlich der Applikationsfähigkeit flüssiger Funktionsmaterialien auf geneigten und gekrümmten Oberflächen untersucht. Auf Basis der gewonnenen Daten entwickelte Modelle werden vorgestellt, die es ermöglichen, die Positionierungsgenauigkeit einzelner Tintentropfen in Abhängigkeit des Arbeitsabstands sowie den elektrischen Widerstand dispenster Leiterbahnen in Relation zu den Dosierparametern Bahngeschwindigkeit und Volumenstrom zu bestimmen. Im Bereich des Inkjet-Drucks wurde darüber hinaus der Nachweis erbracht, dass unabhängig von der Druckkopforientierung in alle Raumrichtungen annähernd gleich weit und genau gedruckt werden kann. Des Weiteren wurde das Fließverhalten von Schichten, die auf geneigte Oberflächen gedruckt wurden, untersucht und aufgezeigt, dass der elektrische Widerstand über die Leiterzüge ohne Inline-Nachbehandlung ungleich verteilt ist und eine Inline-Nachbehandlung vorteilhaft ist. Leiterzüge, die mit Dosierverfahren hergestellt werden, wurden zudem hinsichtlich der Strombelastbarkeit untersucht. Unter Berücksichtigung der im Rahmen der Grundlagenversuche gewonnenen Erkenntnisse wurden eine Inkjet-gedruckte Sitzheizung, dispenste Leiterbahnen zur verlustarmen Stromversorgung eines Fensterhebermotors und ein komplexes hybrides Sensorsystem zur Temperaturmessung realisiert. Die Ergebnisse können für die Realisierung von automatisierten robotergeführten Druckprozessen zur Herstellung von dreidimensionalen Schaltungsträgern überführt werden.

Hydrogen production via the electrolysis of water has gained a lot of attention in the last couple of years. Research related to electrolysers is mostly aimed towards decreasing the noble–metal catalyst content. In this study the presently used catalyst application techniques were reviewed and critically examined to find commercially applicable and effective methods. Selected methods were then practically applied to determine their feasibility and to gain “know–how” related to the practical application of these techniques. The selected techniques were the hand paint, inkjet print, screen print and spray paint techniques. Meaningful comparisons were made between the methods in terms of parameters such as practicality, waste of catalyst and microstructure. The results point out that the hand paint and spray paint methods are feasible methods although there are improvements to be made. The hand paint method was improved by applying a carbon micro porous layer to the gas diffusion layer before the painting is carried out. The addition of the carbon layer reduced the soaking of the catalyst–containing ink through the gas diffusion layer. A method not initially investigated was identified an evaluated and showed promising results in lowering the mass of catalyst applied. This method comprised of sputtering a layer of catalyst material onto a prepared gas diffusion layer. It also came to light from the results that electrodes, and therefore membrane electrode assemblies, can be produced at a much lower cost than the commercial available membrane electrode assemblies. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2012.

Hydrogen production via the electrolysis of water has gained a lot of attention in the last couple of years. Research related to electrolysers is mostly aimed towards decreasing the noble–metal catalyst content. In this study the presently used catalyst application techniques were reviewed and critically examined to find commercially applicable and effective methods. Selected methods were then practically applied to determine their feasibility and to gain “know–how” related to the practical application of these techniques. The selected techniques were the hand paint, inkjet print, screen print and spray paint techniques. Meaningful comparisons were made between the methods in terms of parameters such as practicality, waste of catalyst and microstructure. The results point out that the hand paint and spray paint methods are feasible methods although there are improvements to be made. The hand paint method was improved by applying a carbon micro porous layer to the gas diffusion layer before the painting is carried out. The addition of the carbon layer reduced the soaking of the catalyst–containing ink through the gas diffusion layer. A method not initially investigated was identified an evaluated and showed promising results in lowering the mass of catalyst applied. This method comprised of sputtering a layer of catalyst material onto a prepared gas diffusion layer. It also came to light from the results that electrodes, and therefore membrane electrode assemblies, can be produced at a much lower cost than the commercial available membrane electrode assemblies. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2012.

In this thesis I address the research question: 'How has the Internet delivered pluralism by promoting structural diversity and/or content diversity in Australia's newspaper industry?' Structural diversity is defined here as diversity in newspaper ownership and content diversity as the diversity of views published by individual newspapers. Central to the thesis is the notion of pluralism, the belief that the news media should provide a range of views and opinions, contradictory as well as complementary, to allow informed citizens to effectively take part in the democratic process. The newspaper industry in this country, however, is controlled by a powerful press oligopoly across a range of markets, a situation believed to greatly limit pluralism. A review of newspaper ownership and circulation from 1986 to 2002 shows that, as at 2002, four newspaper owners are the sole occupants of Australia's national and capital city newspaper market. Seven owners are predominant in Australia's regional daily newspaper market, although just three owners controlled 69 per cent of the market's circulation in 2002. Two owners controlled 69 per cent of Australia's suburban newspaper market in 2002. Similar trends were seen in the country's Saturday newspaper and Sunday newspaper markets. In all markets except the regional daily newspaper market, News Limited is the dominant newspaper owner. Australian Provincial News and Media is the dominant owner in the regional daily newspaper market with a 27 per cent share of circulation in 2002. Australia's concentrated newspaper ownership structure has led to a number of formal inquiries into diversity in the industry since 1980. In this thesis I review two of these inquiries, the 1991-92 House of Representatives Select Committee on the Print Media (the Print Media Inquiry) and the 2000 Productivity Commission Inquiry into Broadcasting, to determine (among other things) the nature of and the relationship between structural and content diversity as they apply to Australia's newspapers. (By virtue of major media groups' involvement in the Productivity Commission's inquiry - particularly News Limited, Publishing and Broadcasting Limited and, to a lesser extent, Rural Press - this inquiry, although broadcast-oriented, considered Australia's newspaper industry at length.) This review shows both inquiries were clear on how they saw this relationship - structural diversity is necessary for content diversity. However, the Print Media Inquiry suggested it was almost impossible to guarantee structural diversity in the nation's newspaper industry. The Productivity Commission, meanwhile, said that while it accepted content diversity was not inconsistent with media ownership concentration, it was more likely to be achieved where there was diverse ownership. With the relationship between structural and content diversity in mind, and the Print Media Inquiry's and the Productivity Commission's beliefs that new entrants in the newspaper industry were unlikely in the short term, I examine the suggestion that the Internet has the potential to increase structural diversity in Australia's newspaper industry by allowing new players to efficiently enter the industry via the World Wide Web. The extent to which this might occur is determined by a study of 18 Australian newspaper websites with one argument being that if established newspapers find the transition online relatively easy, then independent online-only news sites might be similarly established. Mings and White's four online news business models - a subscription model, advertising model, e commerce-based transactional model and partnership-based model - are used as a framework to examine the study's results. The study shows Australia's experience mirrors international experience in terms of the growth of newspapers online and in terms of their lack of profitability. It shows that 28 per cent of the newspapers surveyed maintained their circulation while offering free online news content, while a further 33 per cent registered circulation increases. Advertising revenue increased for seven of the nine newspaper websites containing advertising, suggesting that, for some Australian newspapers at least, gaining online advertising (as opposed to gaining overall profitability) has proved successful. And while the survey shows little evidence of Australian newspapers using the transactional model in any real sense, it does show that Australian newspapers are forming local online partnerships with other media and non-media businesses to facilitate their online activities. The study's key finding is that of the 18 newspapers surveyed, just two websites were profitable. This finding is consistent with literature that highlights a lack of commercially viable independent online news ventures both in Australia and internationally. While considerable hopes were held that the Internet would introduce more structural diversity into Australia's newspaper industry, I argue that the Internet's commercial imperatives, as they apply to newspapers, have to a large extent precluded it from adding structural diversity in the industry. In these circumstances, it may be that the only viable way of increasing content diversity in the nation's newspaper industry is to increase the availability of diverse information sources to journalists. I propose that one way to do this is via the Internet. The extent to which this is occurring is determined by a survey of Australian journalists' Internet use, the survey results showing that 97.4 per cent of the journalists who responded now use the Internet regularly, including 97.5 per cent of newspaper journalists. But most journalists who responded use the Internet as a preliminary research tool and as a way to check facts rather than as a means of accessing diverse news sources. The respondents' top five Internet uses, for example, are to e-mail work colleagues, to undertake preliminary research, to access media releases from websites, to verify facts and to search other news organisations' websites. They access major news organisation websites most frequently, followed by government websites, university/research institution websites and corporate/company websites. The least frequently accessed websites are those that could conceivably provide the alternate views demanded by pluralism: online news and current affairs discussion groups and websites set up by private individuals. The survey shows the types of websites Australian journalists most frequently access are linked to the credibility they give to information contained on those websites. Major news organisation websites are seen as providing the most credible information, followed by university/research institution websites and government websites. Websites perceived as providing the least credible information were those that host online news and current affairs discussion groups and websites set up by private individuals. The survey also shows Australian journalists have not embraced online reader interaction to any extent, lessening the likelihood that readers will be able to provide journalists with more diverse news sources. Less than 20 per cent of journalists interact with readers via the Internet and less than 10 per cent use this interaction to create or follow up news stories. The survey does provide results that support source diversity, however. It shows that almost a third of Australian journalists have obtained additional news sources via the Internet. The Internet has also allowed more than 40 per cent of journalists to access individuals or groups that they would not otherwise have accessed. The survey also shows that journalists who have had experience working in the online media environment consistently use the Internet more productively, in terms of diversity, than other journalists. It is these journalists that interact online with readers more, that participate in online discussion groups more and that appear more willing to seek online information from non-traditional sources such as independent news websites and the websites of private individuals or groups. Journalists with online media experience also represent the group that has most sought training in online journalism and online media practice and that most believes the Internet will play an increasingly important role for journalists and news consumers in the future. At present, the survey suggests, journalists with this online media experience comprise just 19 per cent of Australian journalists. But as the number of journalists with online media experience increases in the workforce, these journalists' greater acceptance of the Internet may then assist in greater source diversity leading to greater content diversity in Australia's news media. The studies of newspaper websites and journalists' Internet use suggest and support differing diversity models. In this thesis I propose two models for diversity, the first drawn from views espoused by the Print Media Inquiry and the Productivity Commission's Inquiry into Broadcasting. This model (below) sees a one-to-one correspondence between structural and content diversity and assumes that to increase the diversity of views available to the public, the number of media outlets must similarly be increased. The argument that the Internet can provide media pluralism by permitting new players to enter the media market relatively easily, an argument tested by my study of Australian newspaper websites, is commensurate with this model. The second model is based on my inquiries into journalists' Internet use and proposes a method of increasing content diversity within a fixed media ownership structure. This model (below) acknowledges that journalists produce content mostly via traditional news sources, but proposes this content can be increased and/or changed, with an emphasis on more diverse information, via non-traditional news sources obtained via the Internet. The success of this model, however, is predicated on journalists' acceptance of online information as a viable news source. The implication for journalism is that established journalistic norms and practices, which can limit online-supported content diversity, need to be overcome. Overall, the results of my inquiries suggest the answer to the research question is that the Internet has so far delivered little in terms of structural and content diversity in Australia's newspaper industry. However, the Internet's potential to do so remains, particularly if independent online-based media ventures find ways to become commercially viable and if journalists adopt the technology as a means of finding more diverse news sources.