Electrically conductive smart textiles are a very interesting area that could be important for the development of smart textiles. Today, conductive yarns and threads are often produced from coveted metals such as silver, copper and gold. These metals require large resources to be extracted and processed into yarns and threads and have a major impact on humans and the environment. One way to reduce the consumption of metals and save resources is to coat yarns of textile materials with electrically conductive polymers. In this study, we will investigate coating yarns with the conductive polymer blend PEDOT-PSS. PEDOT-PSS is extracted from oil, which is a non-renewable raw material, but coating with this polymer dispersion has many other advantages over metals and its production chain. Like coating yarn through a chemical bath produces very little waste, the yarn has a smaller mass, the yarn becomes more flexible, and it is easy to scale up production. However, previous studies have shown that there are some difficulties when it comes to coating yarns with PEDOT-PSS. The coating becomes fragile and brittle and to some extent affects the yarn that is coated in terms of mechanical properties. In this study, its investigated how the yarn is affected by various parameters in the production line, such as drying temperature, the viscosity of the PEDOT-PSS dispersion and the speed of the thread traveling through the production line, to find optimal production parameters that provide a balance between conductive and mechanical properties. We have produced a number of samples, all with different variations of parameters, and investigated how its conductive and mechanical properties are affected to see if there is a pattern and connection between parameters and conductive and mechanical properties on the yarn. The results show that yarn samples made with high viscosity of the PEDOT-PSS dispersion are among the lower range of resistance (with some exceptions), with average values of about 2990 O up to 10300 O, while lower viscosity shows uneven results with average values of about 92,000 O and all the way up to about 6,500,000 O. Most samples with lower measured O values are made with a high drying temperature, but no clear connection could be detected between temperature and end result, nor did the different speeds show any clear connection to the result. For the mechanical properties, it turns out that there is a relationship between result and viscosity as well as result and drying temperature. Samples made with low viscosity and low drying temperature perform best in the mechanical tests, 59.7% to 52.9% elongation and 25 cN / tex to 21 cN / tex. While speeds in this category could not show any connection between the results either. Overall, the results can be summarized as the results of tests show that there are some correlations between the parameters and the properties of the yarn samples and that the viscosity of the PEDOT-PSS dispersion and drying temperature are the most influential parameters. For conductive properties, viscosity has the greatest effect and for mechanical properties, viscosity and temperature have the greatest effect. For conductive properties, high viscosity is good, and for mechanical properties, low temperature and low viscosity are best. The sample with the best combination of test results was tested in a knitting machine but the variant chosen for knitting did not have good enough mechanical properties for the knitting machine used and broke when exposed to the stress from the knitting process. Therefore, the knitting test was not successful, but it was possible to sift out what parameter of the production line that had the greatest impact on the coated yarn properties.

Nutrient dynamics in the Archean-Paleoproterozoic oceans strongly influenced primary productivity and the rise of atmospheric O2. Reconstructing the cycling of key nutrients such as dissolved inorganic phosphate (DIP) at this time is important for our understanding of the timing, rate and extent of atmospheric oxygenation at this time. Banded iron formations (BIF) can be used as proxies for global DIP content in Precambrian marine waters. Estimating Precambrian DIP requires understanding of the mechanisms by which Fe(III)(oxyhydr)oxides scavenge DIP which has come mainly from experimental studies using NaCl solutions that mimick Precambrian marine conditions with for example, elevated Si and Fe(II) concentrations. The two DIP binding modes suggested for Early Proterozoic marine waters are 1) Adsorption - surface attachment on pre-formed Fe(III) (oxyhydr)oxides, and 2) Coprecipitation - incorporation of P into actively growing Fe(III) (oxyhydr)oxides. It has been suggested that the elevated Si concentrations suggested for Precambrian seawater, strongly inhibit adsorption of DIP in Fe(III)(oxyhydr)oxides. However recent coprecipitation experiments show that DIP is strongly scavenged by Fe(III)(oxyhydr)oxides in the presence of Si, seawater cations and hydrothermal As. In this study we show that the DIP uptake onto Fe(III)(oxyhydr)oxides by adsorption is less than 5% of that by coprecipitation. The data imply that in the Early Proterozoic open oceans, the precipitation of Fe(III)(oxyhydr)oxides during mixing of deep anoxic Fe(II)-rich waters with oxygenated ocean surface waters caused DIP removal from surface waters through coprecipitation rather than adsorption. Local variations in DIP and perhaps even stratification of DIP in the oceans were likely created from the continuous removal of DIP from surface waters by Fe(III)(oxyhydr)oxides, and its partial release into the anoxic bottoms waters and in buried sediments. In addition to a DIP famine, the selectivity for DIP over As(V) may have led to As enrichment in surface waters both of which would have most likely decreased the productivity of Cyanobacteria and O2 production. / Näringscirkulationen i haven under arkeikum och paleoproterozoikum påverkade primärproduktionen och uppkomsten av atmosfärisk syrgas (O2). För att förstå när och hur fort koncentrationen av O2 i atmosfären ökade behöver vi rekonstruera hur viktiga näringsämnen, t.ex. löst oorganiskt fosfor (engelska “Dissolved Inorganic Phosphorous”, DIP) cirkulerade. Bandad järnmalm (engelska “Banded Iron Formations”, BIF) kan användas som en markör för DIP i de prekambriska haven. För att kunna använda DIP som markör måste man förstå hur prekambrisk DIP tas upp av järn(III)(oxyhydr)oxider. Hittills har detta studerats med natriumkloridlösningar som ska efterlikna förhållande i de prekambriska haven, med t.ex. förhöjda kisel- och järn(II)-koncentrationer. Ur sådana studier har två bindningsmekanismer föreslagits för paleoproterozoiskt havsvatten 1) Adsorption, d.v.s. DIP binds till ytan på redan bildade kristaller av järn(III)(oxyhydr)oxid, och 2) samutfällning, d.v.s. upptag av fosfor i kristaller av järn(III)(oxyhydr)oxid medan kristallerna bildas. Det har föreslagits att de höga kiselkoncentrationerna som tros ha funnits i de prekambriska havsvattnet hämmade adsorption av DIP på ytan av järn(III) (oxyhydr)oxidkristaller. Men de senaste samutfällningsexperimenten tyder på att järn(III) (oxyhydr)oxid effektivt tar upp DIP även i närvaro av kisel, arsenik från hydrotermala källor och de katjoner som dominerar i havsvatten. I här presenterad studie var mängden DIP som bands till järn(III)(oxyhydr)oxidkristaller genom adsorption mindre än 5 % av den DIP som togs upp av kristallerna via samutfällning. Våra data tyder på att när järn(III) (oxyhydr)oxid fälldes ut i tidiga-proterozoiska hav när järn(II)-rikt djupvatten blandades med syrerikt ytvatten, och att DIP avlägsnades från ytvattnet genom samutfällning snarare än adsorption. Lokala variationer av DIP-koncentrationer i haven, möjligen även skiktning, kan ha orsakats av kontinuerlig utfällning av järn(III)(oxyhydr)oxider ur ytvattnet följt av partiell frigörelse av DIP i syrefria djupvatten och sediment. Kristallisationsprocessen, som gynnar inbindning av DIP och misgynnar inbinding av arsenik (V) kan ha orsakat brist av DIP och anrikning av arsenik i ytvattnet, vilket troligen minskade tillväxten av cyanobakterier med lägre syrgasproduktion som följd. / CLAPO

京都大学 / 0048 / 新制・課程博士 / 博士(エネルギー科学) / 甲第17795号 / エネ博第278号 / 新制||エネ||58(附属図書館) / 30602 / 京都大学大学院エネルギー科学研究科エネルギー社会・環境科学専攻 / (主査)教授 石原 慶一, 教授 東野 達, 准教授 奥村 英之 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM

The unique combination of high specific strength and ductility in third generation advanced high-strength steels (3G-AHSSs) has garnered significant attention from top automotive steel industries. These materials are being considered as potential options for making lighter body components due to their strength and ability to tolerate thinner material cross-sections. However, galvanizing these steels through the continuous hot-dip galvanizing process is challenging, because the main alloying elements such as Mn, Si, Al, and Cr tend to selectively oxidize on the steel surface during the annealing process before being immersed in the galvanizing bath containing Zn(Al, Fe). The presence of these oxides extensively covering the substrate surface can negatively impact reactive wetting, coating adhesion, and overall coating quality. In this study, the selective oxidation kinetics and reactive wetting of a series of Fe-(2-10)Mn-(0.00/0.01/0.03)Sb (at. pct) were determined and a model was proposed for analyzing oxide growth during intercritical annealing prior to galvanizing. Annealing heat treatments were carried out at 676, 725, 775, and 825 ˚C for 60-480s holding time in a N2-5vol pct H2 process with a dew point of –10 ˚C. MnO was formed on all samples after annealing. It was determined that the annealing conditions (temperature and isothermal holding time) affected the external oxide thickness and depth of the oxidation zone, which in turn influenced the MnO growth rate. With increasing the bulk Mn content of the alloy, the Mn elemental flux to the external surface increased, resulting in an increase in the oxidation parabolic rate constant. The average activation energy of internal oxidation for the Fe-2Mn, Fe-6Mn and Fe-10Mn alloys were determined to be 216±15 kJ/mol, 178 ± 18 kJ/mol and 152 ±10 kJ/mol, respectively, which are consistent with the activation energy of oxygen diffusion through MnO interfaces and the bulk diffusion of oxygen in austenite. Moreover, the average activation energy for external oxide growth was ~113±18 kJ/mol, which was attributed to the diffusion of Mn cations along the grain boundaries of the external Mn oxides. It was determined that micro addition of Sb to the Fe-Mn alloys led to a reduction in the oxidation rate constant, external oxide thickness, and internal oxidation zone, which was attributed to Sb segregation at both the external and internal oxide interface, resulting in the reduction of oxygen permeability. The reduction was more significant in the Fe-10Mn alloys, primarily attributable to the increased Sb segregation at the interfaces. The research showed that when the bulk Mn content increased, more antimony (Sb) segregated at both the internal and external oxide/substrate interface. As a result, the oxygen present at these interfaces decreased. This is attributed to the reduction of Sb solubility in α-Fe with increasing Mn and positive interactions between Sb and Mn. Advanced Atom Probe Tomography (APT) analysis confirmed that as more Sb segregated at the interfaces, the excess oxygen reduced due to site competition between O and Sb. Additionally, Sb surface segregation kinetics for Fe-(0.01/0.03)Sb and Fe-2Mn-(0.01/0.03)Sb at.% were determined based on the modified Darken model and linear heating followed by isothermal annealing. After the annealing, Sb segregation was detected on the surface of both the Fe-xSb and Fe-2Mn-xSb alloys, which increase with increasing temperature and holding time. The segregation rate, as determined from the Darken curves, was higher in Fe-Sb alloys compared to Fe-2Mn-Sb alloys, which can be attributed to variations in the crystal structure and the density of defects within the metal matrix. Additionally, the activation energy for Sb diffusion in both Fe-Sb and Fe-2Mn-xSb alloys were determined to be approximately 193±18 kJ/mol closely aligns with the activation energy of Sb bulk diffusion in α-Fe. Simulated galvanizing treatments were conducted on Fe-(2-10)Mn-(0.00/0.03)Sb at.% alloys. It was found that Sb segregation at the external/oxide interface resulted in a decrease in the size and thickness of the external oxide particles, which can facilitate better contact between the zinc bath and the substrate. Furthermore, it was found that Sb segregation at the interface between the external oxide and substrate led to a decrease in the stability of the interfacial region. This effect was attributed to an increase in the local atomic spacing near the interface, caused by Sb segregation. As a result, a local strain was observed near the interface. This localized strain significantly reduced the energy needed to separate the oxide from the metal matrix, contributing to decreased stability of the interfacial region. The higher bulk manganese (Mn) content led to increased segregation of antimony (Sb), resulting in a greater local strain within the interfacial region. These effects, in turn, enhanced the kinetics of the aluminothermic reduction reaction and assisted oxide lift-off. Furthermore, the closely packed Fe-Al intermetallics at the coating/steel interface increased as a result of adding Sb to the steel. In addition, no Sb segregation was observed at interfacial layer/metal interface. This absence of segregation can be attributed to the dissolution of segregated Sb into the liquid zinc. It was determined that Sb, which segregated at the external oxide/substrate interface during annealing, dissolved into the zinc bath and disrupted its bond with iron. This disruption occurred due to the higher electronegativity of Sb compared to Fe with Zinc, as well as the sufficient solubility of Sb in liquid zinc. / Thesis / Doctor of Science (PhD) / The unique combination of high specific strength and ductility exhibited by third-generation advanced high-strength steels has captured the attention of automotive industries. However, challenges arise when attempting to galvanize these steels through continuous hot-dip galvanizing processes. The selective oxidation of alloying elements during annealing can have detrimental effects on reactive wetting and coating adhesion. The objective of this research was to improve the coating quality of Mn-containing steels by introducing micro-additions of Sb. Sb segregation to the surface and interfaces began to occur during annealing. Segregated Sb resulted in a reduction of the oxidation rate. Sb segregation at oxide interfaces also contributed to decreased oxygen permeability. Upon immersion in the liquid zinc bath, both Sb and Fe dissolved into the zinc, leading to the formation of an interfacial layer on the surface, which indicates successful reactive wetting. The findings of this research provide valuable insights for improving galvanizing processes and enhancing coating quality, specifically in the context of third-generation advanced high-strength steels.

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Yes / Dynamic wetting failure was observed in the simple dip coating flow with a series of substrates, which had a rough side and a comparatively smoother side. When we compared the air entrainment speeds on both sides, we found a switch in behaviour at a critical viscosity. At viscosity lower than a critical value, the rough side entrained air at lower speeds than the smooth side. Above the critical viscosity the reverse was observed, the smooth side entraining air at lower speed than the rough side. Only substrates with significant roughness showed this behaviour. Below a critical roughness, the rough side always entrained air at lower speeds than the smooth side. These results have both fundamental and practical merits. They support the hydrodynamic theory of dynamic wetting failure and imply that one can coat viscous fluids at higher speeds than normal by roughening substrates. A mechanism and a model are presented to explain dynamic wetting failure on rough surfaces.

Dimmuborgir is thought to be a former rootless shield volcano, which was fed with lava from a nearby crater row, 2170 ± 38 calendar years before present. In this study, the orientation of striations on the sides of lava channels, collapse structures and lava pillars were measured to find out how the enigmatic ~2 km by 2 km volcanic structure at Dimmuborgir was drained. During one week of field work 149 striations were found and measured, with respect to their dip angle, dip direction and elevation. Their locations were recorded with a GPS (Global Positioning System) receiver. The orientations of the striations were visualized on Google Earth satellite images and on images from a Digital Terrain Model (DTM) of Dimmuborgir. Resulting visualizations show that Dimmuborgir was drained radially and in multiple stages. It is concluded that Dimmuborgir was drained towards the west, the northeast and the southeast. The drainage towards the west was channeled. The drainage towards the northeast and the southeast was radially inwards, towards the collapsed parts of Dimmuborgir.

A revista Atlântico foi parte integrante de um projeto maior açambarcado por Portugal e Brasil no começo da década de 1940. Para sermos mais precisos, 1941 é o ano da assinatura do acordo cultural luso-brasileiro que resultou, dentre outros elementos, na idealização de um projeto cujo cerne assenta-se na criação de uma revista de cultura e arte. Desse processo, surge Atlântico, revista que deve seu nome ao intento de encontrar uma palavra suficientemente elástica, ondulante, para sintetizar o vago e o concreto das nossas aspirações, o sonho e a realidade do nosso ideal, segundo as palavras de um dos seus diretores, António Ferro. Fundada em 1942, a revista Atlântico tem como propugnadores o diretor do Secretariado da Propaganda Nacional (SPN) de Portugal, António Ferro, e o diretor do Departamento de Imprensa e Propaganda (DIP), Lourival Fontes. A presente pesquisa, que abrange o período de 1941 (ano da assinatura do Acordo Cultural luso-brasileiro) a 1945 (que marca tanto o fim da vigência do DIP quanto o término da primeira fase de Atlântico), pretende discutir a idéia defendida por seus articulistas de que a natureza da revista Atlântico, isto é, por ser um periódico de cultura, de literatura e de arte, abstêm-se de tratar dos problemas sociais, políticos ou econômicos do mundo moderno, até quando dizem respeito à vida do Brasil ou de Portugal. Ademais, pelo fato de congregar um feixe de intelectuais bastante diversificado, a análise sistemática da revista Atlântico objetiva avaliar e compreender a maneira pela qual autores e obras aparecem no corpo da publicação. / The Atlântico magazine was part of a larger project encompassed by Portugal and Brazil in the early 1940s. More precisely, in 1941 is signed the Luso-Brazilian culture agreement that resulted, among other elements, in the idealization of a project based on creating a magazine of culture and art. From this process arises Atlântico magazine, which owes its name to the attempt of finding a word sufficiently elastic, undulating to synthesize the vague and concrete of our aspirations, dreams and the reality of our vision, in the words of one of its directors António Ferro. Founded in 1942, the Atlântico magazine has had as proponents, António Ferro, the director of Secretariado da Propaganda Nacional (SPN) (Director of the Bureau of Propaganda Nacional) of Portugal and the director of the brazilian Departamento de Imprensa e Propaganda (DIP) (Department of Press and Propaganda), Lourival Fontes. This article, which covers the period from 1941 (year of the signing of the Cultural Luso-Brazilian) to 1945 (which marks both the end of the term of the DIP and the end of the first phase of the Atlântico), aims to discuss the idea defended by its writers that the nature of the Atlântico magazine is to be a journal of culture, literature and art, avoiding dealing with social problems, political or economic in the modern world, even when they concern to life in Brazil or Portugal. Moreover, the fact of bringing a bundle of intellectual rather diverse, systematic analysis of the Atlântico magazine aims to evaluate and understand the way in which authors and works appearing in the body of the publication.

Este trabalho analisa a propaganda oficial do Brasil nos Estados Unidos da América, de 1930 a 1945, no anseio de entender como o governo capitaneado por Getúlio Vargas estabeleceu uma política de promoção da imagem do Brasil naquele país. A organização da propaganda externa contou com atuação dos seguintes órgãos: Departamentos de publicidade/propaganda, principalmente o Departamento de Imprensa e Propaganda (DIP); Escritório de informações brasileiras nos EEUU, ligado ao Ministério do Trabalho, Indústria e Comércio; postos diplomáticos do Ministério das Relações Exteriores; além dos órgãos norte-americanos: Office of the Coordinator of Inter-American Affairs (OCIAA) do governo estaduninse; e American Brazilian Association, de natureza privada. Destaca-se o fato de que cada órgão brasileiro, a sua maneira, concebia e realizava, com relativa autonomia, ações de promoção da imagem positiva do País nos Estados Unidos. Os elementos em comum às formas de propaganda desses órgãos foram as ações empregadas, a exemplo do envio de notícias aos jornais, análise das matérias sobre o Brasil, acolhida de personalidades, promoção de intercâmbios artísticos, educacionais e científicos, fomento a publicações informativas sobre o País como as revistas Brazil, Brazil Today e Travel in Brazil. Destaca-se a contratação, de maneira informal, do famoso redator da coluna Washington Merry-Go-Round, Drew Pearson, como agente de imprensa do Brasil. Essas ações detinham também um mesmo público-alvo, composto de jornalistas, empresários, políticos, intelectuais, militares e demais personalidades consideradas formadoras de opinião; ou seja, pessoas que podiam, de algum modo, interferir ou influenciar os rumos dos interesses nacionais nos assuntos externos dos EUA / This study analyzes the Brazilians government propaganda in the United States, from 1930 to 1945, which to aim to understand how the government headed by President Getúlio Vargas established a Brazil\'s image in that country. The organization of the Brazilian propaganda abroad featured by performance of the following agencies: Departamento de Imprensa e Propaganda (DIP); Brazilian Information Bureau, diplomatic posts owned by the Brazilian Ministry of Foreign Affairs, the Itamaraty; and the American organizations: Office of the Coordinator of Inter-American Affairs (OCIAA) of U.S government; American and Brazilian Association, a private agency. Noteworthy is the fact that every Brazilian agency, in its way, conceived and performed with relative autonomy, actions to promote the positive image of the Brazil in the U.S. The common elements of forms of propaganda were employed, such as sending news to American newspapers, analysis of news about Brazil in the American Press, welcoming American personalities, promotion of artistic, educational and scientific exchanges, fostering informative publications about Brazil, such as magazines Brazil, Brazil Today and Travel in Brazil. The Brazilian government hired, informally, Drew Pearson, the editor of the famous column Washington Merry-go-round, as press agent of Brazil. These actions held by the same audience, composed of journalists, businessmen, politicians, intellectuals, military and other persons considered public opinion makers; that is, people who could in any way interfere with or influence the direction of national interests in foreign affairs in U.S.