| 1. |
- André, Hampus, 1989
(författare)
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Resource and Environmental Impacts of Resource-Efficiency Measures Applied to Electronic Products
- 2018
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Natural resources such as ecosystems, land, water and metals underpin the functioning of economies and human well-being, and are becoming increasingly scarce due to growth in population and affluence. Metals are increasingly demanded for their specific properties as modern technology develops. The dependence on metals is of growing concern due to the environmental impacts related, for example, to energy use and local impacts from mining, as well as the scarcity risks posed by socio-economic, geological and geopolitical constraints. Thus, there is a clear need to use metals and other natural resources more efficiently. The vision of a circular economy has been proposed as a way to do this, for example by improving durability, reusing, repairing and recycling. Such so-called resource-efficiency (RE) measures are commonly assumed to be environmentally beneficial, although the evidence is not plentiful. It is plausible that focusing on recirculating products and materials could shift burdens to other environmental impacts or life cycle stages. It has therefore been argued that a life cycle-based approach, such as in life cycle assessment (LCA), is useful to critically assess the environmental implications of RE measures. LCA aims to quantify the environmental impacts of products over their entire life cycles - from cradle to grave - assessing a wide range of impacts such as toxicity, climate change and metal resource use. For metal resource use, however, there are a number of perspectives as to what constitutes the actual environmental problem. These perspectives are represented in a variety of life cycle impact assessment methods (LCIA) which have previously been shown to give diverging results. Electronic products are emblematic of metal resource use challenges since they deploy a broad spectrum of scarce metals. This thesis aims to provide knowledge on the potential for RE measures to reduce the environmental impacts of electronic products, by addressing the following research questions: (1) What resource-efficiency measures result in reduced potential environmental impacts and resource use – for what types of products and under what conditions? (2) How does extended use of electronic products through design for increased technical lifetime, reuse and repair affect environmental impacts, particularly metal resource use? (3) How does the application of different LCIA methods for metal resource use influence interpretations of resource-efficiency measures applied to electronic products? This thesis builds on three appended papers which are all based on comparative assessments of resource efficiency, studied as resource use and environmental impacts per function delivered, using LCA and material flow analysis. The results indicate that extended use of electronic products through increasing technical lifetimes, reusing and repairing, is generally resource-efficient. Exceptions may occur, however, if extended use is insufficient to motivate impacts from producing more durable products or spare parts. Use extension of electronic products leads to resource efficiency in two distinct ways: through the intended use extension and by increasingly steering material flows into recycling. Further resource efficiency could be realised by combining RE measures over the entire life cycles of products. With regards to metal resource use, the choice of LCIA method can influence the interpretation of the results of RE measures for electronic products. Therefore, it is advisable to use several complementary LCIA methods to minimise the risks of overlooking potentially important resources issues. Furthermore, better understanding and transparency of such issues is valuable in order to provide more comprehensive information to decision-makers.
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| 2. |
- Handirk, Rebekka, 1994
(författare)
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Legacy fostering the twins. Connecting the S/X and VGOS telescope network generations
- 2024
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- With the VLBI Global Observing System (VGOS) being the next step in the development of geodetic Very Long Baseline Interferometry (VLBI), it is necessary to connect the new VGOS network to existing legacy S/X telescopes. Specially designed short-baseline interferometry sessions aim to obtain local-tie vectors between these telescope generations at observatories that have both legacy S/X and new generation VGOS telescopes. At the Onsala Space Observatory (OSO), this is being done by short-baseline interferometry between the VGOS Onsala Twin Telescopes ONSA13SW and ONSA13NE, and the legacy antenna ONSALA60. Similarly, short-baseline interferometry sessions referred to as NYTIE have been performed at Ny-Ålesund, involving the VGOS telescope NYALE13S and the legacy S/X antenna NYALES20. In both cases, these dedicated experiments yielded station coordinates and baselines with mm or even sub-mm accuracy. This thesis focuses on exploring the possibilities of connecting co-located radio telescopes with short-baseline interferometric measurements, specially in the cases of the observatories in Onsala and Ny-Ålesund.
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| 3. |
- Sadd, Matthew, 1994
(författare)
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In-situ Investigations of Lithium-Sulfur Batteries
- 2019
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- As the demand for high energy-density storage devices increases, we must look beyond the current state of the art technology, the lithium-ion battery. Lithium-ion battery technologies are approaching their theoretical limit in terms of capacity, and now that the demand for longer-range electric vehicles (EVs) and the implementation of grid storage is increasing, we need to provide technologies that can go beyond what is currently possible. In order to increase the capacity of batteries, and to develop more sustainable technologies to meet the rising demand, we must turn to new chemistries. A suggested Next-Generation Battery chemistry is based on the electrochemical reaction between lithium and sulfur. This chemistry does not rely on intercalation reactions as the Li-ion battery is, but instead employs conversion chemistry. At discharge elemental sulfur is reduced and converted to polysulfides, yielding a maximum specific capacity of 1672 mAhg-1, up to 6 times the theoretical maximum capacity of state-of-the-art Li-ion battery materials. Thus, the lithium-sulfur technology is a suitable successor due to a potentially higher energy density. In addition, there is also the potential to create sustainable systems made from low-cost and high abundance elements, while also creating less toxic and safer devices than those which are currently available for commercially. In our quest to reach a working lithium-sulfur battery there are a series of challenges that must be addressed, many of which originate from the complex reactions and mechanisms of the lithium-sulfur cell. Soluble Li-polysulfide species are formed during cell operation in commonly used electrolytes, these species are highly mobile and react with the Li-metal anode used. This interaction leads to the unwanted reduction of polysulfide species at the anode, causing the polysulfide shuttle, and capacity fade due to the irreversible deposition of active material on the Li-metal surface. A series of methods have been used to address the unwanted reactions, such as the use of novel additives in the electrolyte to form a stable solid-electrolyte interphase (SEI). In this thesis the unique character of polysulfide species is addressed, and methods discussed will show how control of polysulfide dissolution and speciation can be used to improve cell performance. This improvement is realised by designing new electrolytes that block the passage of polysulfides to the Li-metal anode’s surface, and by using polysulfide species in the electrolyte to enable longer lifetime cells by preventing sulfur dissolution while simultaneously supplementing the energy density of a cell by acting as a Li-salt. However, the mechanism of how the polysulfide species behave is not fully understood. To monitor how polysulfides interact with the Li-metal when they act as charge carriers, operando Raman spectroscopy has been employed to track polysulfide concentration changes in a cell and reveal new insights on the mechanisms of polysulfides as Li-salts.
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| 4. |
- Balksten, Kristin, 1977-
(författare)
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Kalkputs : porstrukturens betydelse för beständighet
- 2005
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- When restoring historic lime plaster it can be difficult to reach the required durability. Today newly made lime plaster can fall off due to frost damages after only a couple of winters. To understand and solve these problems, the subject has been studied from different perspectives. Several factors in the production step are making an influence on the durability of lime plaster: 1. A binder, suitable for the building, must be chosen along with sandthat gives good material properties in both fresh mortar and in plasters. 2. The lime/sand ratio and the mixing technique should be chosen from the properties in the lime and the sand, in order to get a mortar with good workability. 3. The craftsmanship should be adjusted to the mortar, the weather and the underlying materials. A plaster with good frost resistance has a certain pore structure. The plaster should have some round air pores that contain air even when the material is filled capillary with water. Such air pores give the water a free space to expand when it is freezing. If the air pores are missing, the ice crystals may damage the plaster when expanding. To increase the chance of making a frost resistant lime plaster, the lime/sand ration must be adjusted so the lime can fill up well in the sand. Otherwise a collapsed pore system can easily occur, which means an open pore system without distinct air pores. A collapsed pore system contains many pores well connected with each other. Such a system is easily damaged by frost. To increase the chance of success, it is of great importance to work the surface of the lime plaster at the right time and in the correct way. Before working on a surface the mortar must be aloud to stiffen. Only then a homogeneous material can be created; cracks due to shrinkage can be pressed together and the result is a more compact material with an open surface. The time necessary for mortars to stiffen is related to the water content of the mortar, the suction of the underlying surface and the weather conditions. If the surface is worked on while the mortar is still fresh, the binder can form a hard lime shell on the surface. Inside thematerial a lack of binder can appear. Such plasters have a very low frost resistance. Other durability problems related to plaster are damages in the underlying materials, i.e. rotten wood in covered constructions or leached lime in old joints. Such damages can occur if the covering mortar is made of strong hydraulic lime or cement, since they form plasters with a low permeability in comparison to lime. Due to mentioned findings, it is important to study how a pore structureis influenced by materials, mixture and craftsmanship. Only then it is possible to understand how damages can be decreased.
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| 5. |
- Bursjöö, Ingela, 1963
(författare)
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Lärares formande av en yrkesidentitet relaterad till hållbar utveckling
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Swedish schools are required to educate for sustainable development (ESD). The challenges for the teachers are demanding as the content is controversial and complex. This study focuses on exploring the different ways teachers and student teachers reflect upon their approach to ESD. Of particular interest is how they talk about the dilemmas they confront in their teaching. 1. How do teachers and student teachers describe their approach to ESD? 2. How do teachers and student teachers reflect on their personal lifestyle in relation to their professional teacher identity? For the purposes of this study a qualitative approach with interview questions were designed and conducted. This study uses open-ended questionnaires combined with focus-group as well as individual interviews. The teachers and the student teachers were asked about their reflections on their approach to ESD and how their own lifestyle affects their teaching credibility. The different phases of transformative learning were used as an analytical tool in order to better understand the variation in ways participants made meaning of ESD. Student teachers’ approaches to ESD depend on both external and internal factors. Three major external factors have been found: colleagues, time and the curriculum. The answers also describe the teaching methods in ESD as collaborative and interdisciplinary; ESD requires individual skills as well as a collective competence. The practicing teachers in the study have not received any professional development concerning education for sustainable development. However, all of them have a reflected explanation of how they teach for sustainable development. The different perceptions held by the teachers are categorized in three dimensions, described as a focus dimension, an action dimension and a reflection dimension. The focus dimension shows the direction of the teaching practice, a possible difference between environmental education and education for sustainability. The reflection dimension shows an identification of a transformative process and the action dimension could reveal a description of a dilemma. These three dimensions could be visualized in a 3D space of teachers’ approaches to education for sustainable development. All of the teachers and the student teachers describe education for sustainable development as difficult to teach since it involves conflicts and contradictions. The student teachers express more comfort in content and teaching methods, on the other hand they perceive more tensions with colleagues, time constraint and their lifestyle. Some teachers in the study even avoid education for sustainable development because of its political connotations. This implies that ESD is, indeed, difficult, and involves choices of different approaches to ESD such as normative, fact-based and pluralistic. ESD is a contested concept and involves controversial values which lead to dilemmas for the teacher. Dilemmas and critical self- reflection are important for transformative learning. These results may be important to teacher education as well as to teachers’ professional development as they provide insights for implementation of changes in the educational system. The use of the different phases of transformative learning as an analytical tool could also contribute to the understanding of how teachers form their professional identity. The findings also provides an opportunity to perform longitudinal studies as a way to identify different trajectories of teacher´s learning processes in a dynamic and changing educational system. Still, much work remains to identify, analyse and improve different aspects of teaching, in order to be able to stress that the implementation of ESD is based on both research and best practice.
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| 6. |
- Dauriach, Alice, 1991-
(författare)
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Financial institutions, companies, and the biosphere
- 2022
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- International organisations, governments and civil society have become increasingly vocal in their demands that financial institutions take social and environmental responsibility for the companies they invest in. Some financial institutions have started to assume this responsibility in practice by building international alliances and standards, by reallocating their capital, and by trying to influence corporate policies towards environmental and social goals. Through their ability to allocate and price capital, financial institutions are sometimes believed to be a leverage point to enact rapid and large-scale change towards sustainability. The influence these financial institutions have is still under-researched, however, especially on companies in sectors associated with changes in the biosphere which pose severe risks to human development. In this thesis, I ask: to what extent can financial institutions advance biosphere-based sustainability through their investments in companies? I have three main aims. The first one is to identify key companies and financial institutions which can be linked to changes in the biosphere that pose severe risks to human wellbeing. I select the most critical commodity production sectors driving large-scale biosphere change using insights from social-ecological systems science. I focus on economic activities that result in anthropogenic land use changes that either affect known tipping points in the climate system (the Amazon rainforest), or that increase the risk of emergence and re-emergence of vector-borne and zoonotic diseases. The second aim is to develop methods to assess the degree of influence that financial institutions have on corporate activities, drawing from finance research and management theory. I investigate the relationship between financial institutions and large companies, and especially to what extent companies are reliant on different financial flows for their operations, in order to determine through which mechanisms financial institutions could exert influence on them, if at all. Assessing the potential influence of financial institutions on companies requires combining existing methods and bringing together disconnected sources of data about environmental impact, business activity, investments, and financing sources. The third aim is to analyse what factors pose limits to financial influence.Paper 1 analyses the role played by financial institutions as owners in industries associated with anthropogenic land use changes and, as a result, increased zoonotic disease risks. We identify publicly listed companies present in nine regional case studies, as well as the financial institutions that invest in them. We analyse those financial institutions’ potential influence based on both their ownership size and their position in the network of owners.Paper 2 examines the origin of loans obtained by all companies operating in the high deforestation-risk sectors of mineral production, soy trade or cattle trade in the Brazilian Amazon. We assess to what extent companies rely on relatively unaccountable sources of credit, notably credit from secrecy jurisdictions and transnational intra-company credit, which may limit the potential for influence from financial institutions.In conclusion, I find that financial institutions have an important role to play in many sectors and regions analysed, but that this role is limited by a number of factors. These factors include the prevalence of non-financial shareholders in some companies, especially in case studies in the Global South, and the reliance of companies on internal finance and financial flows from secrecy jurisdictions. Companies themselves, and the inner workings of their corporate groups – their private owners, their subsidiaries in various countries, their ethical stance – seem to also be of great importance.
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| 7. |
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| 8. |
- Eriksson, Jonny, 1963
(författare)
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Bruk av kalk och sand ur ett hantverkligt perspektiv
- 2015
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Sweden has a thousand-year history of burning (calcinating) and slaking (hydrating) limestone to produce a binder for mortar and stucco. We can assume that the conditions for manufacturing such binders have varied from one part of the country to another. The reason for such an assumption is that limestone is a collective term for a variety of stone types that consist primarily of the mineral calcite but whose properties and composition vary from place to place. In some places, the local limestone has been affected by heat and pressure to produce crystalline limestone. Lime must be burned and slaked in different ways depending on its composition and attributes. From a historical perspective, it is likely that knowledge of the techniques for manufacturing lime binders developed through successive experimentation as kiln types and slaking methods were adapted to the local limestone. Other factors that may have influenced the development of lime binder manufacturing are the availability of fuel and the demand for binder product. For the purposes of this research project, we examine the production of lime binder from the geological layers of limestone in Kinnekulle and the nearby communities, where we may assume the limestone found in buildings has been quarried locally. These include Gillstad Church, Väla Church, and Källstorp Manor Chapel. So far the project has included: - Survey of Kinnekulle limestone usage - Development of lime kilns for burning of lime - Development of methods and tools for slaking lime Besides providing data for study and analysis, Gillstad Church, Väla Church, and Källstorp Manor Chapel have been used as case studies in the use of locally manufactured lime. Additional studies are planned for other areas with locally occurring limestone resources. At the request of the National Property Board, and as part of the research project, we have burnt and slaked lime for the restoration of stucco work at Läckö Castle. This commission has benefited the project by increasing the volume of burned and slaked lime, which has illuminated some of the choices that may have traditionally influenced the choice of limestone, kiln type, kiln temperature, and slaking method.
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| 9. |
- Fremling, Christoffer, 1984-
(författare)
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PTF12os and iPTF13bvn : Two stripped-envelope supernovae discovered by the Palomar Transient Factory
- 2016
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis is based on research made by the intermediate Palomar Transient Factory [(i)PTF], and it is particularly closely tied to the still ongoing research on the stripped-envelope (SE) supernova (SN), iPTF13bvn (Type Ib), that occurred in the nearby galaxy NGC 5806. This SN was initially thought to have been the explosion of a very massive Wolf-Rayet (WR) star, but I have shown that this is very likely not the case. I suggest instead that the most likely scenario is that iPTF13bvn originated from a binary system where the envelope was stripped off from the SN progenitor by tidal forces from a companion star, in a similar way as for the very well studied Type IIb SN 2011dh. I have also investigated another SE SN, PTF12os (Type IIb), that occurred in the same galaxy as iPTF13bvn, with the conclusion that PTF12os and iPTF13bvn are very similar amongst themselves, and that both of them are also remarkably similar to SN 2011dh, in terms of all of the available observations (light-curves, spectra). Hydrodynamical models have been used to constrain the explosion parameters of iPTF13bvn, PTF12os and SN 2011dh; finding 56Ni masses in the range 0.063 − 0.075 M⊙, ejecta masses in the range 1.85 − 1.91 M⊙. Using the 56Ni-masses derived from our hydrodynamical modeling in combination with nebular models and late-time spectroscopy we were able to constrain the Zero-Age Main Sequence (ZAMS) mass to ∼ 12 M⊙ for iPTF13bvn and ≲ 15 M⊙ for PTF12os. In current stellar evolution models, stars with these masses on the ZAMS cannot lose their hydrogen envelopes and become SE SNe without binary interactions.
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| 10. |
- Giusti, Matteo
(författare)
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Nature Routines of Children as Leverage Point for Sustainable Social-Ecological Urbanism : Connecting childhood and biosphere to design sustainable civilizations in the human habitat
- 2016
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Strong sustainability requires enhanced knowledge and understanding of complex social-ecological interactions, but it also implies a ‘novel’ conceptualization of the relationship between humans and nature, one in which individuals perceive themselves as embedded members of the Biosphere. The aim of this Licentiate thesis is to investigate the validity of a strategy that is centered on designing the urban green infrastructure to nurture such human-nature relationship in children’s attitudes. The research is framed by spatial cognition, conservation psychology, and social-ecological sustainability and it focuses on the validity of this strategy. Hence, the Licentiate analyzes how reoccurring experiences of nature that are situated in the everyday habitat (i.e. nature routines) affect personal human-nature attitudes and how these can be implemented as leverage points to change social-ecological systems using sustainable urbanism. Paper 1 tests the assumed link between the nature routines in Stockholm and preschool children’s development of cognitive and emotional affinity to nature. The results show that nature-rich routines over a period of four years are significantly correlated with the strength of preschooler’s affinity with nature. Paper 2 uses a mixed methods approach to evaluate changes in Connection To Nature (CTN) in 10 years olds who partake in a project of nature conservation. The results of Paper 2 show that there is an evaluative gap between theory and practice in connecting children with nature that impedes the evaluation of how children’s CTN changes over short periods of time and that impedes the creation of an evaluative framework for nature experiences. Paper 3 considers these empirical results in theorizing an approach to sustainable urban design based on social-ecological sustainability that includes CTN. In order to overcome existing limitations Paper 3 presents the concept of cognitive affordances as a theoretical tool to embed cognitive and emotional attitudes towards nature into the design of urban spaces. All combined these papers provide valid evidence that nature routines in cities, especially for children, can be a significant leverage point to enable future sustainable civilizations.
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