<p> This thesis consists of studies carried out on the Nickel-Cobalt alloy system. The surface segregation behaviour has been studied over the range of composition from 14 to 90 atomic percent Nickel using Auger Electron Spectroscopy (AES). An analysis procedure has been developed that is based on computer simulation of observed spectra using pure metal standard spectra and has resulted in excellent matches. Nickel has been observed to segregate over the entire range of compositions studied and the driving force for segregation has been investigated by monitoring the equilibrium surface composition over a range of temperatures from 813 to 1100 K. The enthalpy and entropy of segregation has been determined on single grains of orientations (111) and (210) in a sample of composition 56.0 atomic percent Nickel as well as on the (111), (100) and (110) faces of a 50.0 atomic percent Nickel single crystal.</p> <p> The initial stage of oxidation has also been studied here using Scanning Auger Mapping and digital image processing. The initial stage of oxidation carried out in-situ has been shown to proceed via an island nucleation and growth mechanism which has been confirmed by imaging islands based on the oxygen Auger signal. A preliminary study of the effects of temperature and pressure on the island growth stage of oxidation has been completed and results are reported.</p> / Thesis / Doctor of Philosophy (PhD)

京都大学 / 新制・課程博士 / 博士(地域研究) / 甲第24977号 / 地博第319号 / 新制||地||124(附属図書館) / 京都大学大学院アジア・アフリカ地域研究研究科東南アジア地域研究専攻 / (主査)教授 岡本 正明, 教授 古澤 拓郎, 准教授 町北 朋洋, 特定准教授 馬塲 弘樹 / 学位規則第4条第1項該当 / Doctor of Area Studies / Kyoto University / DGAM

Abstract This thesis examines segregation and stigmatization in Rosengård, Malmö, and proposes adesign concept to change the area's image. Previous studies have shown disparities in living conditions and linked Malmö's housing segregation to socio-economic and ethnic factors.The city of Malmö is working to reduce segregation by combating prejudices and creatingattractive environments. This thesis explores the segregated and stigmatized exclusion in Rosengård and presents a design proposal to create an appealing and inviting neighborhood. The proposal includes four existing parks in Malmö Rosengård—Vänskapsparken, Rosengårdsfältet, Skulpturparken, and Vattenlekplatsen—integrated into a larger park and anattractive art museum. By utilizing theories and conducting interviews with the urban plannerand residents who have different relationships with Rosengård, this proposal aims to create an appealing and cohesive space. The method that has been used is based on a case study that uses inspired ethnographicmaterial, such as observations and interviews on site in the area. In addition, to complete thestudy, an analysis of people's movement patterns and gathering points was conducted. Also apark mapping, photographic mapping of the parks, questionnaire surveys at various locations,a Lynch analysis and use of the "research by design" method were carried out. Literaturestudies and articles were also used to build up the survey and the design proposal. The theoretical framework employed in the study supports the research. It draws on variousauthors, including Per-Markku Ristilammi (1999), Mikael Stigendal (1999), Tapio Salonen,Martin Grander, and Markus Rasmusson (2019), Lena Magnusson (2001), Susanne Urban(2018), and Anna Lisa Lindén (1989). Additionally, Rosengren &amp; Striner's work (2011) shedslight on Rosengård and its historical background, taking a more positive standpoint. To shedlight on whether current efforts and integration measures were based on Malmö municipality(2019, 2021) and the City Planning Office (2014, 2019), were used. The results of the study indicated a need for attractive and inclusive outdoor environments in Rosengård. The findings emphasized the importance of green spaces, art and culturalactivities, as well as meeting places for social interaction and integration. Safety and reducedsegregation are also crucial for creating a more harmonious and inclusive neighborhood. These results provide valuable insights and serve as guidance to design an effective design strategy and implement measures that will enhance the attractiveness of Rosengård and fosteran integrated community. In conclusion, transforming the built environment in Rosengård has the potential to promotestronger integration with the surrounding city. Stigmatization and negative perceptions arecommon issues in the area that can lead to segregation and isolation. The study compiles anddeepens the knowledge about the area by building upon previous research. It also offersproposals for solutions to promote integration, reduce segregation, and combat stigmatization. / Sammanfattning Studiens resultat visade att det finns behov av attraktiva och inkluderande utomhusmiljöer i Rosengård. Resultaten betonade vikten av grönområden, konst- och kulturverksamheter samt mötesplatser för social interaktion och integration. Trygghet och minskad segregation ärockså avgörande för att skapa en mer harmonisk och inkluderande stadsdel. Dessa resultat ger viktig insikt och fungerar som en vägledning för att utforma en effektiv designstrategi och vidta åtgärder som kommer att förbättra Rosengårds attraktivitet och skapaen integrerad gemenskap. Slutsatsen är att förändringarna av den byggda miljön i Rosengård skulle kunna leda till enstärkt integration med den omgivande staden. Stigmatisering och dåligt rykte är ettutmärkande problem för området som kan leda till segregation och isolering. Studien sammanställer och fördjupar kunskapen om området genom att bygga på tidigare forskning. Den erbjuder också förslag till lösningar för att främja integration, minska segregationen och bekämpa stigmatiseringen. Detta examensarbete undersöker segregation och stigmatisering i Rosengård i Malmö och föreslår ett eget designförslag för att förändra områdets image. Tidigare studier har visat skillnader i levnadsvillkor och kopplat Malmös bostadssegregation till socioekonomiska och etniska faktorer. Malmö stad arbetar för att minska segregationen genom att bekämpa fördomar och skapa attraktiva miljöer. Detta examensarbete undersöker det segregerade och stigmatiserade utanförskapet i Rosengård och presenterar ett designförslag för att skapa enattraktiv och lockande stadsdel. Förslaget innefattar fyra befintliga parker i Malmö Rosengård, Vänskapsparken, Rosengårdsfältet, Skulpturparken och Vattenlekplatsen som integreras till en större park och ett attraktivt konstmuseum. Genom användning av teorier och intervjuer med planarkitekten och invånare som har olika relationer till Rosengård bidragit till utvecklingen av detta förslag, vilket avser att skapa en attraktiv och sammanhållen plats. Syftet med denna studie är att undersöka de underliggande orsakerna till segregation och utanförskap i stadsdelen Rosengård, baserat på tidigare forskning som identifierat faktorer och mekanismer som bidrar till detta problem. Studien syftar även till att föreslå åtgärder och strategier för att skapa en mer inkluderande och sammanhållen stadsdel. Metoden som har använts är baserad på en fallstudie som använder sig av etnografisktmaterial, såsom observationer och intervjuer på plats i området. Dessutom, för attkomplettera studien, genomfördes en analys över människors rörelsemönster och samlingspunkter. Även en park kartläggning, fotografisk kartläggning av parkerna,enkätundersökningar på olika platser, en Lynch-analys och användning av "research bydesign"-metoden. Även litteraturstudier, artiklar användes för att bygga upp undersökningen och designförslaget. Teorin som används i undersökningen stödjer min undersökning. Jag har här utgått från fleraförfattare, bl.a. Per-Markku Ristilammi (1999), Mikael Stigendal (1999), Tapio Salonen,Martin Grander och Markus Rasmusson (2019), Lena Magnusson (2001), Susanne Urban(2018) och Anna Lisa Lindén (1989). Jag har dessutom utgått från Rosengren &amp; Striner(2011) som belyser Rosengård och dess historiska bakgrund, också från en mer positiv utgångspunkt. För att belysa om nuvarande insatser och integrationsåtgärder utgick frånMalmö stad (2019, 2021) och Stadsbyggnadskontorets (2014, 2019). Studiens resultat visade att det finns behov av attraktiva och inkluderande utomhusmiljöer i Rosengård. Resultaten betonade vikten av grönområden, konst- och kulturverksamheter samt mötesplatser för social interaktion och integration. Trygghet och minskad segregation ärockså avgörande för att skapa en mer harmonisk och inkluderande stadsdel. Dessa resultat ger viktig insikt och fungerar som en vägledning för att utforma en effektiv designstrategi och vidta åtgärder som kommer att förbättra Rosengårds attraktivitet och skapaen integrerad gemenskap. Slutsatsen är att förändringarna av den byggda miljön i Rosengård skulle kunna leda till enstärkt integration med den omgivande staden. Stigmatisering och dåligt rykte är ettutmärkande problem för området som kan leda till segregation och isolering. Studien sammanställer och fördjupar kunskapen om området genom att bygga på tidigare forskning. Den erbjuder också förslag till lösningar för att främja integration, minska segregationen och bekämpa stigmatiseringen.

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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This paper discusses the issue of residential segregation in Halmstad, a municipality in western Sweden. The inhabitants themselves say that it is one of the most segregated municipalities in the country and the growing segregation is affecting the community in various ways, particularly in the housing market, where increased segregation has resulted in decreased quality and safety in these areas, as well as decreased cohesion between different areas in the municipality. The paper aims to explain the forms of residential segregation in society using four theories: The planning hypothesis, market hypothesis, status hypothesis, and contact hypothesis. The research method used is the case study method, which is suitable for analyzing a “case” of broader phenomenon. One method that has been considered appropriate within the case study literature for testing theories, as this study does, is pattern matching, also known as congruence matching. This method tests the extent of which the empirical pattern matches the hypothetical pattern that the theory assumes. If there is lack of congruence between the empirical pattern and the theoretically assumed pattern, the result speak against the theoretical hypothesis. If the congruence is found, the theoretical hypothesis is supported. The planning hypothesis could confirm that the municipality ́s planning has had segregated effects and the efforts have not been sufficient to counteract residential segregation. The market hypothesis could not be confirmed because the housing market is not governed by market rents. The paper also found patterns that strengthened the status hypothesis. Partly by finding material that shows that Halmstad is a polarized municipality with areas that have lower status than others. Lastly, the contact hypothesis could partly be confirmed by looking at increased family immigration.

Residential segregation is a major challenge facing Swedish cities today, with its consequences putting a significant toll on society as a whole. Gothenburg Municipality has named segregation the municipality ́s biggest challenge and one of the main focuses for the municipality to handle going forward. With this increased focus on segregation in the municipality of Gothenburg, this thesis is set out to study the municipality ́s view and interpretation of residential segregation as a problem and, through that, the municipality’s ambitions and policies to tackle segregation. This has been done through semi-structured interviews with officials within the municipal organisation, spanning multiple departments and document analysis of the main municipal documents laying out Gothenburg municipality ́s work on residential segregation. The results of this thesis show a multi-faceted approach to the municipality ́s ambitions to tackle segregation, with different approaches being favoured among the municipal departments. With the growing concern for the problems with residential segregation, new policies taking a different approach on its view of the foundational problem with segregation.

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