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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Chokladganache : En studie om temperering som tillagningsmetod

Hukkanen, Felicia, Åström, Fredrika January 2016 (has links)
No description available.
2

”Det handlar om att hitta sprickorna i muren” : En studie av de som härbärgerar gömda

Johansson, Robert January 2012 (has links)
Denna studies övergripande syfte är att studera hur personer som härbärgerar flyktingar  ser på relationen mellan individers handlingar och hela samhällets ansvar för  flyktingarna. För att uppnå syftet studeras tre mer konkreta frågeställningar; hur  människor som härbärgerar papperslösa finner legitimitet för sin handling, hur de tror  att andra människor i samhället ser på deras engagemang och vad de själva tycker om  människor som inte är engagerade i detta.  Studiens teoretiska utgångspunkt bygger på Jürgen Habermas arbete för att  begreppsligöra civil olydnad. I syfte att sätta in dessa i en förståelse hur informanterna  ser på sig själva i relation till samhället används också Georg Simmels teoretiska tankar  om samhället utifrån hans begrepp; kristallisering, dubbel kategorisering av människor  och församhälleligande (vergesellschaftung).  Som metod för att samla in studiens källmaterial används en tematiskt öppen intervju.  Kodning och analys genomförs med så kallad databaserad kodning, som sedan med  hjälp av identifierbara underteman (antingen förbestämda eller skapade av  informanterna) försöker bena ut en tankestruktur hos informanterna som kan besvara på  studiens frågor. Resultatet av studien visar att legitimeringen har två delar. En är att de bistår med akuta  åtgärder som exempelvis tak över huvudet för människor i nöd, den andra är att de vill  ändra "systemet" på längre sikt.  När det gäller den andra frågan, menar informanterna  att de i många fall beskrivs som hjältar av andra. Den sista frågan kan delas upp i två  delar. En del som gäller myndigheter, där informanterna har svårt att förstå hur de som  arbetar med dessa frågor kan rättfärdiga/legitimera sina handlingar. Samtidigt tror de  också att det går att förändra dem, genom att hjälpa dessa att tänka kritiskt. När det  gäller den andra delen, andra i samhället, är de övertygade om att fler i samhället skulle  bli aktiva om de faktiskt blev tillfrågade.
3

Electrolyte

Fritz, Judit January 2021 (has links)
Title of work: Electrolyte Artist: Judit Fritz Konstfack, Ädellab   ABSTRACT How much of the ocean have I filtered while in tears? Many times, while growing up on an island have I laid eyes on the enormous surrounding body of water and wondered – is the sorrow still in there? In small portions the human body and the bodies of nature exposes each other as part of their own content. Offering a glimpse into a constant material flow. Diffusing the boundaries between object and subject. A material flow that makes it impossible to tell what anything really is, because it has already evolved. My tears taste like the ocean. So does my sweat. I Find comfort in knowing I constantly take part in something that is beyond my human comprehension. That I don’t need to fully understand why I am here, because it is obvious that I, and everyone else play a part. We just don’t know the whole scene. Though a post humanistic angle I have investigated the close relation between matter, material, the human body and the bodies of nature, to find a connection point which decreases the hierarchy between object and subject. By crystallizing matter derived from human body fluids and building a machinery that portrays the process I invite the perceiver to a closeup of their part in a never-ending system. The agency of this project is to raise questions rather than finding answers, as I believe the human is in need of reevaluating their way of thinking when it comes to material and resources. I have tried to shift focus from the human perspective and self-centeredness into a set where we participate rather than being the perceiver. Alchemy was used as both a method and as an art historical reference, as the alchemical mindset is to learn through the act of making. This has been blended with modern days technology and imagination to build a body of work that balances between science and art. While being heavily based on theory and research, the body of work is a translation in which I allowed myself to freely portray how I imagine the travelling of matter is systemized. I created a working place where studies of the unseen is concentrated and visualized. Where the many sorrows and the hard work of human beings crystallize into solids, becoming nature again. Or was it ever not? And vice versa. Throughout the project, even though separated from everything that I connect to being human, the crystals made from pure matter derived from sweat and tears could not be separated from the knowledge of their origin. Even as objects, I see them as subjects. A conclusion that shed light upon the relativeness between bodies. A conclusion that brings life into what is often seen as dead, simultaneously showing the complex machinery of an emotional being.
4

Influence of Nucleation Techniques on the Degree of Supercooling and Duration of Crystallization for Sugar Alcohol as Phase Change Material : Investigation on erythritol-based additiveenhanced Composites

Lin, JiaCheng, Teng, HaoRan January 2019 (has links)
Utilizing Phase Change Materials (PCM) for Latent Thermal Energy Storage (LTES) applications have previously been extensively researched as a measure to reduce greenhouse gas emissions from energy consumption. In order to make use of the waste heat from industrial processes for LTES purposes, a new demand emerged for PCMs capable of phase change in mid-temperature ranges of 100 °C - 200 °C. This higher temperature requirement made most of the previously studied material inapplicable as they had much lower melting and solidification temperatures. With this in mind, a new generation of PCMs consisting of Sugar Alcohols (SA) has been proposed. Erythritol is seen as an especially promising SA with good thermophysical properties for LTES purposes. However, it has been shown to suffer from severe supercooling, which makes it unreliable in real applications. To eradicate this issue, two additives, Graphene Oxide (GO) and Polyvinylpyrrolidone (PVP) at varying mass fractions were mixed with pure erythritol to form a composite which was studied using the Temperature-history (T-history) method to determine its effectiveness in reducing supercooling. Results show that at its most effective mass fraction, GO reduces supercooling by 28 o C and a 31 o C reduction is seen by the addition of PVP. The impacts on the duration of crystallization was also documented and analyzed using the same method. It was observed that the duration of crystallization was increased with increasing mass fractions of the additives. Other important properties of the composites were also studied in order to determine the overall feasibility for industrial applications. It includes analysis of the storage capacity through latent heat, changes in viscosity along with impacts on thermal diffusivity of the composites. / Att använda fasändringsmaterial (PCM) för termisk energilagring i form av latent värme (LTES) har tidigare extensivt forskats och undersökts som en lösning för att minska utsläppen av växthusgaser från energiförbrukning. För att utnyttja spillvärme från industriella processer för LTES-ändamål uppstod en efterfrågan på PCM som ändrar fas i temperaturer mellan 100 °C - 200 °C. Detta krav på högre temperatur gjorde att de flesta av de tidigare aktuella materialen inte kunde tillämpas eftersom de hade mycket lägre smält- och kristalliseringstemperaturer. Med detta i åtanke har en ny generation av PCM bestående av sockeralkoholer (SA) föreslagits. Erytritol ses som ett särskilt lovande SA med goda egenskaper för LTES-ändamål. Den har dock visat sig drabbas av svår underkylning, vilket gör den opålitligt i verkliga tillämpningar. För att utrota detta problem blandades två tillsatser, Graphene Oxide (GO) och Polyvinylpyrrolidone (PVP) vid olika massfraktioner med ren erytritol för att bilda en komposit som studerades med metoden Temperature-history (T-history) för att bestämma dess effektivitet på att minska underkylningen. Resultaten visar att GO på sin mest effektiva massfraktion minskar underkylningen med 28 o C och tillsats av PVP lyckats minska den med som mest 31 o C. Påverkningarna på varaktighet av kristallisering dokumenterades och analyserades med samma metod. Det var observerad att varaktigheten av kristallisering ökades med ökande massfraktioner av tillsatserna. Även andra viktiga egenskaper hos kompositerna studerades för att avgöra rimligheten att använda dessa för industriella tillämpningar. Det inkluderar analys av lagringskapaciteten genom latent värme, förändringar i viskositet tillsammans med påverkan på kompositernas termiska diffusivitet.
5

Influence of Nucleation Techniques on the Degree of Supercooling and Duration of Crystallization for Sugar Alcohol as Phase Change Material : Investigation on erythritol-based additiveenhanced composites

Lin, Jiacheng, Teng, Haoran January 2019 (has links)
Utilizing Phase Change Materials (PCM) for Latent Thermal Energy Storage (LTES) applications have previously been extensively researched as a measure to reduce greenhouse gas emissions from energy consumption. In order to make use of the waste heat from industrial processes for LTES purposes, a new demand emerged for PCMs capable of phase change in mid-temperature ranges of 100 °C - 200 °C. This higher temperature requirement made most of the previously studied material inapplicable as they had much lower melting and solidification temperatures. With this in mind, a new generation of PCMs consisting of Sugar Alcohols (SA) has been proposed. Erythritol is seen as an especially promising SA with good thermophysical properties for LTES purposes. However, it has been shown to suffer from severe supercooling, which makes it unreliable in real applications. To eradicate this issue, two additives, Graphene Oxide (GO) and Polyvinylpyrrolidone (PVP) at varying mass fractions were mixed with pure erythritol to form a composite which was studied using the Temperature-history (T-history) method to determine its effectiveness in reducing supercooling. Results show that at its most effective mass fraction, GO reduces supercooling by 28 oC and a 31 oC reduction is seen by the addition of PVP. The impacts on the duration of crystallization was also documented and analyzed using the same method. It was observed that the duration of crystallization was increased with increasing mass fractions of the additives. Other important properties of the composites were also studied in order to determine the overall feasibility for industrial applications. It includes analysis of the storage capacity through latent heat, changes in viscosity along with impacts on thermal diffusivity of the composites. / Att använda fasändringsmaterial (PCM) för termisk energilagring i form av latent värme (LTES) har tidigare extensivt forskats och undersökts som en lösning för att minska utsläppen av växthusgaser från energiförbrukning. För att utnyttja spillvärme från industriella processer för LTES-ändamål uppstod en efterfrågan på PCM som ändrar fas i temperaturer mellan 100 °C - 200 °C. Detta krav på högre temperatur gjorde att de flesta av de tidigare aktuella materialen inte kunde tillämpas eftersom de hade mycket lägre smält- och kristalliseringstemperaturer. Med detta i åtanke har en ny generation av PCM bestående av sockeralkoholer (SA) föreslagits. Erytritol ses som ett särskilt lovande SA med goda egenskaper för LTES-ändamål. Den har dock visat sig drabbas av svår underkylning, vilket gör den opålitligt i verkliga tillämpningar. För att utrota detta problem blandades två tillsatser, Graphene Oxide (GO) och Polyvinylpyrrolidone (PVP) vid olika massfraktioner med ren erytritol för att bilda en komposit som studerades med metoden Temperature-history (T-history) för att bestämma dess effektivitet på att minska underkylningen. Resultaten visar att GO på sin mest effektiva massfraktion minskar underkylningen med 28 oC och tillsats av PVP lyckats minska den med som mest 31 oC. Påverkningarna på varaktighet av kristallisering dokumenterades och analyserades med samma metod. Det var observerad att varaktigheten av kristallisering ökades med ökande massfraktioner av tillsatserna. Även andra viktiga egenskaper hos kompositerna studerades för att avgöra rimligheten att använda dessa för industriella tillämpningar. Det inkluderar analys av lagringskapaciteten genom latent värme, förändringar i viskositet tillsammans med påverkan på kompositernas termiska diffusivitet.
6

Exploring the sense of belonging of Setswana–speaking older women in Ikageng who were forcibly relocated during apartheid / Kolobe P.C.

Kolobe, Patricia Stockie January 2011 (has links)
The social displacement enforced by the South African Group Areas Act between 1954 and 1955 was understandably experienced as a destructive process with physical and emotional consequences arising from various types of losses, separation and feelings of helplessness. Although the forced removals affected all the people in the community - also in later years and generations, it seems as if older people are affected the more as they still remember the losses they experienced when they were removed from their homes and their communities, when their heritage and their culture were displaced. The sense of belonging being experienced by older people, who were subjected to these forceful removals, is therefore unclear. In this study the sense of belonging is defined as the effective participation, involvement, contribution and emersion of people when relating to their social, physical, spiritual, emotional and cultural places. In this study older (aged 60 and above) Setswana speaking residents of Ikageng, a community just outside Potchefstroom in the North West Province, South Africa, who were also forcibly relocated from Kloppersville to Ikageng, 10 kilometers away from Kloppersville, were asked to identify places that are important to them in Ikageng and to describe the meanings they attach to these places. In the research, no one identified any places of importance in Ikageng, instead throughout the research they kept on referring to their lives in Kloppersville, their former place of residence, the place where they were forcibly removed from – giving purpose and direction to this study and leading to the question: What are the experiences related to the sense of belonging of Setswana speaking older women who were forcibly relocated during Apartheid in South Africa? The older persons’ experiences of their sense of belonging in the place where they were forcibly relocated to must be understood in relation to the past. A qualitative research approach was used and a narrative research design followed. Two sets of data were gathered and are reported on in this article that focuses on the narrations of 11 older Tswana people from the Day Care Centre for the Aged in Ikageng. Narrative data collection and analysis, as well as a variety of qualitative research methods and media, were used to collect data. These include: focus group discussions, the Mmogo– MethodTM, videos, audio, photographs and observational notes. The thematic analysis of textual data, narrative–oriented inquiry as well as visual data, established trustworthiness of this research through crystallization. By drawing on the deeper symbolic meaning derived through the use of the MmogomethodTM, the study has revealed that the sense of belonging is a relational phenomenon that cannot be understood in absence of the different relational environments. In an African culture the relationship with the current environment resonates with the effects that historical processes, structural abuses, discrimination, racism and devaluation had on individuals whose lives have been uprooted. This study has shown that the older women have a micro–organic relational sense of belonging to the place of relocation and not to the whole context and other relational environments and that they revealed more sense of belonging towards the place where they were relocated from. / Thesis (M.A. (Research Psychology))--North-West University, Potchefstroom Campus, 2012.
7

Exploring the sense of belonging of Setswana–speaking older women in Ikageng who were forcibly relocated during apartheid / Kolobe P.C.

Kolobe, Patricia Stockie January 2011 (has links)
The social displacement enforced by the South African Group Areas Act between 1954 and 1955 was understandably experienced as a destructive process with physical and emotional consequences arising from various types of losses, separation and feelings of helplessness. Although the forced removals affected all the people in the community - also in later years and generations, it seems as if older people are affected the more as they still remember the losses they experienced when they were removed from their homes and their communities, when their heritage and their culture were displaced. The sense of belonging being experienced by older people, who were subjected to these forceful removals, is therefore unclear. In this study the sense of belonging is defined as the effective participation, involvement, contribution and emersion of people when relating to their social, physical, spiritual, emotional and cultural places. In this study older (aged 60 and above) Setswana speaking residents of Ikageng, a community just outside Potchefstroom in the North West Province, South Africa, who were also forcibly relocated from Kloppersville to Ikageng, 10 kilometers away from Kloppersville, were asked to identify places that are important to them in Ikageng and to describe the meanings they attach to these places. In the research, no one identified any places of importance in Ikageng, instead throughout the research they kept on referring to their lives in Kloppersville, their former place of residence, the place where they were forcibly removed from – giving purpose and direction to this study and leading to the question: What are the experiences related to the sense of belonging of Setswana speaking older women who were forcibly relocated during Apartheid in South Africa? The older persons’ experiences of their sense of belonging in the place where they were forcibly relocated to must be understood in relation to the past. A qualitative research approach was used and a narrative research design followed. Two sets of data were gathered and are reported on in this article that focuses on the narrations of 11 older Tswana people from the Day Care Centre for the Aged in Ikageng. Narrative data collection and analysis, as well as a variety of qualitative research methods and media, were used to collect data. These include: focus group discussions, the Mmogo– MethodTM, videos, audio, photographs and observational notes. The thematic analysis of textual data, narrative–oriented inquiry as well as visual data, established trustworthiness of this research through crystallization. By drawing on the deeper symbolic meaning derived through the use of the MmogomethodTM, the study has revealed that the sense of belonging is a relational phenomenon that cannot be understood in absence of the different relational environments. In an African culture the relationship with the current environment resonates with the effects that historical processes, structural abuses, discrimination, racism and devaluation had on individuals whose lives have been uprooted. This study has shown that the older women have a micro–organic relational sense of belonging to the place of relocation and not to the whole context and other relational environments and that they revealed more sense of belonging towards the place where they were relocated from. / Thesis (M.A. (Research Psychology))--North-West University, Potchefstroom Campus, 2012.
8

Development of a microfluidic device to study simultaneous crystallization in the LIBs recycling process / Utveckling av en mikrofluidisk enhet för att studera samtidig kristallisering i LIB:s återvinningsprocess

Solanki, Shefali Paresh January 2023 (has links)
Återvinning av litiumjonbatterier (LIB) är avgörande på grund av kritiska råmaterialreserver och miljöhänsyn vid kassering. Hydrometallurgisk LIB-återvinning, en framstående industriell teknik, står inför kostnadseffektivitets- och komplexitetsutmaningar. Samtidig kristallisering visar lovande för effektivisering av återvinning genom att extrahera föreningar från förbrukad batterilut med flera komponenter, vilket kräver hög renhet och effektiv kristallseparation. Detta innebär emellertid att man förhindrar oönskade polykristallina partiklar och samkristaller.Kristallisering är vanligt vid LIB-återvinning, men vanligtvis från enkomponentlösningar för att undvika föroreningar. Kärnbildningskontroll, särskilt i flerkomponentlösningar, är fortfarande utmanande, vilket påverkar industriell effektivitet. Sådd, en vanlig kontrollmetod, inducerar ofta oavsiktliga polykristallina partiklar och vätskeinneslutningar, som understuderas på grund av experimentella begränsningar. Microfluidics erbjuder ett värdefullt verktyg för att studera kristallisationskinetik, växla från utrustningsbaserad till prediktiv fysikalisk-kemisk design. Förbättrad blandning och värmeväxling gör den idealisk för kärnbildningsforskning under kristallisation. Denna avhandling fokuserar på avgörande aspekter av samtidig kristallisation. Huvudsyftet är att utveckla en optimerad mikrofluidisk design och simulera mikrofluidikkanalen för att bestämma initiala processparametrar för experiment samt att få det mest förutsägbara området för kristallbildning inom mikrofluidik. Utmaningar i de mikrofluidiska kristallisationssystemen, såsom kanalblockering, som lätt kan uppstå på grund av kristallbildning eller agglomerationer, har tyvärr begränsat de experimentella resultaten. Icke desto mindre kommer denna avhandling att stödja ytterligare experiment med mikrofluidikanordningen under mikroskopi som kommer att hjälpa till att övervinna dessa utmaningar. Arbete med att minska begränsningarna i denna avhandling kan hjälpa till att förstå multikomponentkristallisationen i realtid och faktiskt den nödvändiga uppställningen och infrastrukturen för mikrofluidikexperiment och i förlängningen bidra till att minska de hydrometallurgiska stegen i komplex metallåtervinning. Därför bidrar det till att främja områdena batteriåtervinning, mikrofluidik och samtidig kristallisering. / Recycling lithium-ion batteries (LIB) is essential due to critical raw material reserves and environmental concerns during disposal. Hydrometallurgical LIB recycling, a prominent industrial technology, faces cost-efficiency and complexity challenges. Simultaneous crystallization shows promise for streamlining recycling by extracting compounds from multicomponent spent battery liquor, demanding high purity and effective crystal separation. However, this entails preventing unwanted polycrystalline particles and cocrystals. Crystallization is common in LIB recycling, but usually from single-component solutions to avoid impurities. Nucleation control, especially in multicomponent solutions, remains challenging, affecting industrial efficiency. Seeding, a common control method, often induces unintended polycrystalline particles and fluid inclusions, which are understudied due to experimental limitations. Microfluidics offers a valuable tool for studying crystallization kinetics, shifting from equipment-based to predictive physical-chemical design. Enhanced mixing and heat exchange make it ideal for nucleation research during crystallization. This thesis focuses on crucial aspects of simultaneous crystallization. The main objective is to develop an optimized microfluidic design and simulate the microfluidic channel to determine initial process parameters for experimentation as well as to get the most predictable region of crystal formation within microfluidics. Challenges in the microfluidic crystallization systems, such as channel blockage, which can easily occur due to crystal formation or agglomerations, have unfortunately limited the experimental results. Nonetheless, this thesis will support the further experimentation of the microfluidics device under microscopy which will help to overcome these challenges. Work on reducing the limitations of this thesis can assist in understanding the multicomponent crystallization in real-time and indeed, the necessary setup and infrastructure for microfluidics experiments and in the long run help reduce the hydrometallurgical steps in complex metal recycling. Hence, it contributes to advancing the fields of battery recycling, microfluidics, and simultaneous crystallization.

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