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Skuldsanering : Vägen till ett skuldfritt liv genom skuldsaneringslagen
No full textDenna kandidatuppsats utforskar om de befintliga kraven för skuldsanering i Sverige är nödvändiga och lämpligt utformade, med fokus på om kraven är för strikta och om det är möjligt att lätta på dem utan att riskera systemets integritet. Studien begränsas till att endast behandlade fall där gäldenären ansöker om skuldsanering för första gången, uteslutande den 10§ iskuldsaneringslagen 2016:675 som rör möjligheten till en andra skuldsanering. I uppsatsenanvänds den juridiska metoden för att djupgående analysera skuldsaneringslagen, dessrättskällor, förarbeten samt rättspraxis. Resultaten visar att många ansökningar avslås på grundav att de strikta kraven inte uppfylls, särskilt bland yngre gäldenärer som ofta bedöms hatillräckligt med tid att återbetala sina skulder. Dom höga kraven samt den komplexaansökningsprocessen utgör hinder, särskilt för de som befinner sig i en svår ekonomisksituation
Working Life in the Circular Economy: Taking Stock and Moving Forward
No full textThe circular economy (CE) has for long been an important strategy for sustainable development, promoting resource efficiency through reduce, reuse, and recycle. There is also a growing expectation that the CE may provide new jobs. However, working life dimensions of the CE are often treated separately from environmental and economic concerns. This is unfortunate given the impact that a transition to CE may have on salient issues in working life, including on job security, skills needed, occupational health and safety management (OHSM) and the cooperation between social partners. The lack of integration of environmental, economic and social concerns in CE also risks impeding goal achievement in several policy areas. The present review article synthesises the existing scientific knowledge on a sustainable working life in the transformation towards a CE, and based upon the synthesis, critically explores the knowledge needs in relation to CE and working life: barriers and enablers; labour market changes; OHSM; skills requirements; the role for social partners; and policy challenges. A total of 2487 peer reviewed journal articles were identified, with 27 articles included in the review. Future research should focus on creating and upscaling circular business models that promote transparency, collaboration, and value creation across supply chains, developing educational programs for stakeholders and the workforce. More research is required to evaluate existing policies, design effective policy frameworks, promote circular business models, and addressing employment opportunities and job security. Studies should also investigate how social partners can contribute to working life in the CE and identify necessary processes and agreements.Validerad;2025;Nivå 1;2025-02-25 (u4);Fulltext license: CC BY</p
Synthesizing lignin-based gelators to prepare oleogels used as green and fossil-free greases
No full textTraditional lubricating greases are mainly derived from petroleum, which poses major environmental challenges due to their non-biodegradability and pollution issues. This study attempts to synthesize lignin-based green thickeners and explore their potential for developing green and fossil-free greases. A lignin-based gelator was successfully synthesized by reacting malic acid with lignin and epoxidized soybean oil, in which malic acid participated in both the esterification reaction and the ring-opening of the epoxy group. This synthesized gelator was used as the thickener to prepare greases with several different oils, e.g., castor oil, epoxidized soybean oil, rapeseed oil, PAO 15, and paraffin oil. It was found that combining this lignin-based gelator with castor oil and epoxidized soybean oil can be successfully used for preparing greases, while it does not work with other oils. Rheological studied showed that the 35 % gelator-castor oil grease exhibited strong gel-like behaviour, with storage modulus (G', 400 Pa) exceeding loss modulus (G", 40 Pa) and shear-thinning viscosity reducing from 106 to 104 mPa·s under stress. Comprehensive tribological studies on the developed greases show that lignin-based gelators significantly improve lubricant performance (about 20 % lower friction and around 40 % lower wear under a contact pressure of 2.72 GPa, reciprocating speed 0.1 m/s, and 80 °C). XPS analysis further revealed the ability of the developed grease to form a protective film on metal surfaces. This study demonstrates the great potential of lignin as a green thickener and provides new ideas for developing high-performance, green, and fossil-free greases.Validerad;2025;Nivå 2;2025-03-03 (u2);Full text: CC BY license;</p
Specialistsjuksköterskors erfarenheter av närståendes delaktighet i omvårdnaden inom den psykiatriska heldygnsvården
No full textBakgrund: Psykiatrisk heldygnsvård är vård som bedrivs dygnet runt, på alla årets dagar, och i de allra flesta fall bedrivs denna vård frivilligt men i vissa fall kan även tvångsvård vara aktuell. Omvårdnaden som bedrivs ska vara personcentrerad, evidensbaserad, återhämtningsinriktad och bygga på att både patienten och dess närstående ska vara delaktiga, vilket är en stor del av specialistsjuksköterskans ansvar att inkludera båda parter. Förutsättning är att patienten ger samtycke till närståendes delaktighet, Tidigare forskning fokuserar mest på närstående och patienters perspektiv, där specialistsjuksköterskors upplevelser är mindre forskade på, därav denna studie. Syfte: Att beskriva specialistsjuksköterskors erfarenheter av närståendes delaktighet i omvårdnaden inom den psykiatriska heldygnsvården. Metod: Deltagare till studien har rekryterats via verksamhetschefer inom psykiatrisk heldygnsvård och nio specialistsjuksköterskor deltog i semistrukturerade intervjuer. Intervjuerna har analyserats enligt kvalitativ innehållsanalys med en induktiv ansats. Resultat: Analysen resulterade i fem kategorier; ”Närståendes betydelse i omvårdnaden”, ” Närståendes delaktighet”, ” Sjukvårdens samarbete och strukturer”, ” Begränsningar som hindrar” och ” Specialistsjuksköterskans stöd och information till närstående”. Slutsats: Organisation och omgivningsfaktorer framstår som en viktig förutsättning för att främja närståendes delaktighet inom psykiatrisk heldygnsvård. Författarna har även tagit del av tidigare forskning i området som pekar på att just organisation och omgivningsfaktorer är viktigt för att möjliggöra närståendes delaktighet, med bland annat tid till specialistsjuksköterskan för att kunna utföra sitt arbete i den utsträckning som specialistsjuksköterskan önskar, och som även inkluderar närstående. Upplevelsen är att specialistsjuksköterskor ser närstående som en tillgång inom omvårdnaden. Författarna föreslår vidare forskning i ämnet med fler deltagande specialistsjuksköterskor för att få en bredare förståelse inom området
Accelerated carbonate weathering by immobilized recombinant carbonic anhydrase
No full textCO2 absorption in aqueous alkaline solutions promoted by carbonic anhydrase (CA) has received increased attention as a solution for post-combustion CO2 capture. In particular, accelerated weathering has emerged as an alternative approach for CO2 capture, mimicking nature’s way to sequestrate CO2. In this study, an evolved CA from Desulfovibrio vulgaris was immobilized on magnetic nanoparticles (MNPs) offering a promising solution for the effective enzyme separation and recovery from complex and heterogeneous reaction media. The immobilization yields were high (86–98 %) and MNPs-DvCA8.0 were characterized based on standardized CO2 release and CO2 absorption assays and compared to the free enzyme. As a following step, MNPs-DvCA8.0 were applied as promoter in the accelerated weathering of insoluble lime mud, originating as a residue from a paper and pulp industry. MNPs-DvCA8.0 could be efficiently separated, washed and reused for up to 10 consecutive reaction cycles, offering a biocatalyst productivity equal to 2.83 g captured CO2/g CA opposite to the free enzyme that offered only 1.01 g captured CO2/g CA. CA immobilization could offer a mitigation strategy for the non-selective adsorption of the free enzyme on lime mud particles during the CO2 capturing reaction. The highly reproducible and robust immobilization method, that provides material separation based on its magnetic properties, could be a viable solution for the recovery of enzyme and its separation from the lime mud slurry, aiding in obtaining a highly pure solution rich in bicarbonate, as product.Validerad;2025;Nivå 2;2025-03-10 (u2);Full text: CC BY license;</p
Estimating the effect of punching on out-of-plane bending fatigue of steel sheet specimens
No full textSheet metal punching is an important process in manufacturing of heavy-duty vehicle chassis components. The cut edges have a detrimental effect on high cycle fatigue life in uniaxial- and in-plane-bending but the reduction is less pronounced in out-of-plane bending. This paper aims to explain the reduced process sensitivity in out-of-plane bending fatigue, to quantify the high cycle fatigue life reduction at different load ratios, and to propose a methodology for fatigue life estimation. This could enhance the possibilities to identify critical load cases of chassis components, to judge whether fatigue life improving post-processes are necessary, and to locate critical initiation sites for fatigue. Fatigue testing of punched and polished specimens was conducted, and the punching process and four-point bending were simulated using FEM. The results were used to estimate crack initiation site, fatigue life reduction, and for validating the predictions. Fatigue life reduction is found to increase with increased load ratio, but to a smaller extent than expected. A contributing factor the reduced tensile residual stresses due to plasticity during the first load cycle. The reduced process sensitivity as compared to uniaxial fatigue could be explained by the separate locations of crack initiation and high tensile residual stresses in the cut edge. Specimen orientation seems to have a minor influence on the fatigue life. Only improving the outer surfaces, and not the central parts of the cut edge, could increase the high cycle fatigue life for pulsating and reversed loading.Validerad;2025;Nivå 2;2025-03-03 (u4);Funder: European Union (101157245);Fulltext license: CC BY</p
Identifying Harmonic Sources by Profiling Discrete Harmonic Cycle Time
No full textHarmonic emissions cause power quality issues in electrical systems, making source identification necessary to determine the best way of remedying them. Existing methods rely on measuring variations in harmonic amplitude, angle, and phase which require multiple measurement points or extensive system knowledge. We identified a methodological research gap because Discrete Harmonic Cycle Time (DHCT) has not been evaluated as a measuring principle for harmonic source identification. We propose a method using DHCT to enable single point measurements to profile harmonic sources. To determine the cycle length, we used a combination of sifting, a filter bank of cascaded high-pass and notch filters, and zero-crossing detection. For comparing the devices, we extracted motifs from the time series of discrete cycle lengths and applied principal component analysis. While it has previously been known in other contexts that harmonics can have varying cycle lengths, our laboratory results show that this is also true for the emissions of power electronic devices and that the differentiation can be used to identify the devices, thus bridging this knowledge gap. This method is independent of system impedance and topology. While further validation in more complex environments is needed, our results suggest that devices can be identified using this measurement principle. Since the measuring principle is orthogonal to other methods, it has potential as a complementary tool in harmonic source identification.Validerad;2025;Nivå 2;2025-03-13 (u8);Full text license: CC BY</p
Occurrence and Concentration of 6 Metals and 28 Organic Micropollutants in the Forebays of Bioretention Facilities
No full textPollutant loads in urban runoff from anthropogenic sources contribute to degradation of downstream waters. Cities are turning toward green infrastructure to manage urban stormwater. Bioretention is popular as green infrastructure and is commonly installed to remove runoff pollutants. A significant proportion of pollutants in urban runoff are particulates or particulate-bound and are effectively removed in bioretention cells. Pollutants accumulate in concentrated areas of the bioretention (e.g., forebays, inlets, surficial filter layers), which require maintenance to restore effective treatment and to increase the operational lifespan. Particles trapped in forebays risk diminished effectiveness of the pretreatment, which may eventually lead to filter clogging and leaching of toxic pollutants. Studies have examined pollutant accumulation and distribution in bioretention filter media, but less is known about processes in bioretention forebays. In this study, 28 bioretention forebays were examined in urban areas of Ohio and Michigan (United States) as well as Stockholm and Malmö (Sweden) to investigate the occurrence and accumulation of metals (i.e., Cd, Cr, Cu, Ni, Pb, and Zn) and 38 analytes of organic micropollutants [OMPs, i.e., alkylphenols, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and phthalates]. Investigated metals were present in all 28 samples, except Cd detected in 27 samples. Of 38 OMP analytes, 31 were detected in at least one sample. PAHs and PCBs were the most frequently detected pollutants found at all examined sites. In general, high concentrations of pollutants were detected in all forebay sediments. Cu, Ni, Zn, PAHs with high molecular weight, and PCBs were detected at concentrations above US and Swedish soil quality guidelines. It was concluded that forebays regularly need to be excavated to maintain their function, and excavated sediments must be handled safely during maintenance work and disposal.Validerad;2025;Nivå 1;2025-03-17 (u4);Full text license: CC BY 4.0Dag & Nä
Four Questions for Systemic More-Than-Human Design in Practice
No full textISBN for host publication: 9781032741192, 9781003467731;Full text: CC BY-NC-ND license</p
Simulation of scattering characteristics of Polar Stratospheric Clouds
No full textThis thesis uses simulations to study the scattering characteristics of Polar Stratospheric Cloud (PSC) particles. It focuses on lognormal size distributions to see how scattering changes with changes in particle parameters. The simulations are based on the well-established T-matrix method, employing a dependable and proven program to calculate scattering properties. In-situ measurements derived from the literature are utilized to calculate the input parameters for the simulations. By simulating the scattering of the three main types of PSCs (NAT, STS, and ice), parameters were systematically varied to evaluate their influence on the phase function and scattered intensity at key angles, with particular emphasis on 180°, which is relevant for LIDAR observations. The results strongly suggest that the mean radius of the dominant mode has a significant effect on scattering intensity, with a critical threshold for the small mode when it takes over from the large mode. Particle shape and aspect ratio also have significant effects, especially in the backscatter region. The analysis emphasizes the importance of particle size, shape, and distribution properties in determining PSC scattering characteristics, highlighting their importance in both modeling and observational studies. These findings provide valuable insights into how PSCs scatter light, which is important for accurate remote sensing applications