| 1. |
- Albertsson, Per, 1964, et al.
(författare)
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Positron emission tomography and computed tomographic (PET/CT) imaging for radiation therapy planning in anal cancer: A systematic review and meta-analysis
- 2018
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Ingår i: Critical reviews in oncology/hematology. - : Elsevier BV. - 1040-8428. ; 126, s. 6-12
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Forskningsöversikt (refereegranskat)abstract
- To improve the accuracy of chemoradiation therapy in anal cancer patients PET/CT is frequently used in the planning of radiation therapy. A systematic review was performed to assess impact on survival, quality of life, symptom score, change in target definition and treatment intention. Systematic literature searches were conducted in Medline, EMBASE, the Cochrane Library, and Centre for Reviews and Dissemination. Ten cross-sectional studies were identified. No data were available on survival or quality of life. The summary estimate of the proportion of patients in which PET/CT had an impact on the target definition, was 23% (95% CI 16;33). The corresponding summary estimate of a change in treatment intent from curative to palliative was 3% (95% CI 2;6). Almost one in four patients had a change in target definition, which supports the use of PET/CT in radiation therapy planning, but the consequence regarding survival and quality of life is still uncertain.
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| 2. |
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| 3. |
- Berggren, Anna, et al.
(författare)
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Små avlopp i kretslopp
- 2012
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Rapport (refereegranskat)abstract
- The certification system has provided the prerequisites for recycling fractions from small-scale sewage systems and larger source-separating sewage system to arable land in a quality-assured and trusted manner. Realisation of these ‘ecocycle solutions’ will be highly dependent upon progress by additional municipalities in establishing facilities for treating and recycling fractions from small-scale sewage systems and larger source-separating sewage systems. Key words: slam, avloppsfraktioner, reningsverk, minireningverk, SPCR 178, EN 12566-3, REVAQ, återföring, näring, näringsämnen, wastewater, sewage, sludge
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| 6. |
- Boesen, Jesper, 1971, et al.
(författare)
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Developing mathematical competence: From the intended to the enacted curriculum
- 2013
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Ingår i: Journal of Mathematical Behavior. - : Elsevier BV. - 0732-3123 .- 1873-8028. ; 33:1, s. 72-87
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Tidskriftsartikel (refereegranskat)abstract
- This study investigates the impact of a national reform in Sweden introducing mathematical competency goals. Data were gathered through interviews, classroom observations, and online surveys with nearly 200 teachers. Contrasting to most studies of this size, qualitative analyses were conducted. The results show that teachers are positive to the message, but the combination of using national curriculum documents and national tests to convey the reform message has not been sufficient for teachers to identify the meaning of the message. Thus, the teachers have not acquired the functional knowledge of the competence message required to modify their teaching in alignment with the reform. The results indicate that for complex reform messages, such as the competency message, to have intended impact on classroom practice, special attention needs to be put on the clarity of the message. To have high-stakes tests, for example, does not alone seem to be sufficient. © 2013 Elsevier Inc.
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| 7. |
- Burden, Håkan, et al.
(författare)
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Självkörande landsbygd
- 2021
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Hur skulle autonoma fordon kunna användas inom kollektivtrafiken på landsbygden? Genom intervjuer, workshops och en RFI (request for information, ett första steg mot upphandling) har vi undersökt frågan utifrån fyra konkreta områden i Sverige – Lund, Gotland, Eskilstuna och Skellefteå. Med en definition av landsbygd baserad på individens mobilitet har vi sett att Sveriges landsbygd rymmer mindre orter på väg att avfolkas där äldre, barn och de utan körkort hade kunnat få bättre tillgång till samhällelig service med autonoma fordon. Vi har också sett att flera av landets nya arbetsplatser kommer befinna sig på landsbygden och därmed skapa ett mobilitetsbehov från staden till landet. För att kunna realisera de identifierade möjligheterna finns ett behov av att framföra fordonen i högre hastigheter samt att de ska kunna hantera mer komplexa trafiksituationer än vad dagens piloter i städerna visat. På landsbygden finns alltså ett utrymme för nya fordon att visa upp sig. Samtidigt ser vi hur man inte ska förvänta sig att investeringarna i autonoma fordon kommer betala sig på en linje, snarare behöver man lyfta blicken och se systemeffekten när stomlinjetrafiken blir mer attraktiv då bussarna går raka vägen istället för via mindre samhällen. Vi har inte sett några belägg på att den digitala infrastrukturen behöver utvecklas för att möjliggöra försök med autonoma fordon på någon av de undersökta rutterna. Dagens 4G-täckning är fullgod och fordonen borde ha tillgång till tillräckligt bra positioneringsdata för att bedriva verksamheten. Däremot ställs flera frågor om hur ersättningstrafiken organiseras när fordonen inte klarar av vädret, vem som står för säkrare hållplatser och hur chaufförens övriga ansvar realiseras när fordonet är förarlöst.
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| 8. |
- Carlsson, Per-Ola, et al.
(författare)
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Chronically decreased oxygen tension in rat pancreatic islets transplantedunder the kidney capsule
- 2000
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Ingår i: Transplantation. - 0041-1337 .- 1534-6080. ; 69:5, s. 761-766
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: A factor of potential importance in the failure of islet grafts is poor or inadequate engraftment of the islets in the implantation organ. This study measured the oxygen tension and blood perfusion in 1-, 2-, and 9-month-old islet grafts. METHODS: The partial pressure of oxygen was measured in pancreatic islets transplanted beneath the renal capsule of diabetic and nondiabetic recipient rats with a modified Clark electrode (outer tip diameter 2-6 microm). The size of the graft (250 islets) was by purpose not large enough to cure the diabetic recipients. The oxygen tension in islets within the pancreas was also recorded. Blood perfusion was measured with the laser-Doppler technique. RESULTS: Within native pancreatic islets, the partial pressure of oxygen was approximately 40 mm Hg (n=8). In islets transplanted to nondiabetic animals, the oxygen tension was approximately 6-7 mm Hg 1, 2, and 9 months posttransplantation. No differences could be seen between the different time points after transplantation. In the diabetic recipients, an even more pronounced decrease in graft tissue oxygen tension was recorded. The mean oxygen tension in the superficial renal cortex surrounding the implanted islets was similar in all groups (approximately 15 mm Hg). Intravenous administration of glucose (0.1 gxkg(-1)x min(-1)) did not affect the oxygen tension in any of the investigated tissues. The islet graft blood flow was similar in all groups, measuring approximately 50% of the blood flow in the kidney cortex. CONCLUSION: The oxygen tension in islets implanted beneath the kidney capsule is markedly lower than in native islets up to 9 months after transplantation. Moreover, persistent hyperglycemia in the recipient causes an even further decrease in graft oxygen tension, despite similar blood perfusion. To what extent this may contribute to islet graft failure remains to be determined.
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| 17. |
- Elson, Frank, et al.
(författare)
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TRIM Simulations Tool for μ + Stopping Fraction in Hydrostatic Pressure Cells
- 2023
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Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 2462:1
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Konferensbidrag (refereegranskat)abstract
- For quantum systems or materials, a common procedure for probing their behaviour is to tune electronic/magnetic properties using external parameters, e.g. temperature, magnetic field or pressure. Pressure application as an external stimuli is a widely used tool, where the sample in question is inserted into a pressure cell providing a hydrostatic pressure condition. Such device causes some practical problems when using in Muon Spin Rotation/Relaxation (μ +SR) experiments as a large proportion of the muons will be implanted in the pressure cell rather than in the sample, resulting in a higher background signal. This issue gets further amplified when the temperature dependent response from the sample is much smaller than that of the pressure cell,which may cause the sample response to be lost in the background and cause difficulties in aligning the sample within the beam. To tackle this issue, we have used pySRIM [1] to construct a practical and helpful simulation tool for calculating muon stopping fractions, specifically for the pressure cell setup at the μE1 beamline using the GPD spectrometer at the Paul Scherrer Institute, with the use of TRIM simulations. The program is used to estimate the number of muon stopping in both the sample and the pressure cell at a given momentum. The simultion tool is programmed into a GUI, making it accessible to user to approximate prior to their experiments at GPD what fractions will belong to the sample and the pressure cell in their fitting procedure.
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| 18. |
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| 21. |
- Flodin, Veronica, et al.
(författare)
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Utveckling av trepartssamtal inom kompletterande pedagogisk utveckling (KPU)
- 2020
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Ingår i: Lärarkonferens2020- möjligheter med akademisk lärarskap. ; , s. 25-25
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Trepartssamtalet, dvs ett samtal mellan kurslärare, student och VFU-handledare, är en central del i den verksamhetsförlagda utbildningen (VFU), och dessutom ett av få tillfällen i hela lärarutbildningen där campus, student och skola möts. Studenterna lyfter fram trepartssamtalet i kursutvärderingar som ett av de viktigaste inslagen under utbildningen. Men trepartssamtalet är också kostsamt på olika sätt. Det kostar i tid att resa ut till skolorna och det behövs också många lärare att bemanna dem. Det är därför viktigt att utveckla och utforska olika former för samtal i VFU som inte är en ren minskning av kvalitet, utan kan vara en form som gynnar studenternas lärande.Projektet omfattar två delstudier där I) studerar digitala trepartssamtal och II) studerar trepartssamtal i grupp. Delprojekt I) är en erfarenhetsbaserad studie där vi jämför våra resultat med till exempel Karlstads universitet som har lärarutbildning (och därmed trepartssamtal) på distans (Johansson och Johansson, 2018). Delprojekt II) innebär trepartssamtal med studentpar, och genomförs som en möjlig aktivitet inom klustren i den nya VFU-organisationen. Studier har visat att studenter som gör VFU i par eller grupp har möjlighet att genom gemensam planering och gemensamma reflektioner hitta kopplingar mellan den egna undervisningen och innehållet i de lästa kurserna (Cavanagh & McMaster, 2015; Manuchechrie, 2002). Delprojekt II sker också i samverkan med VFU-kursansvariga vid institutionerna HSD och ISD.Under paneldiskussionen kommer vi presentera resultaten i de olika delprojekten, vad vi har lärt oss och vilka utmaningar som vi kan ställas inför, till exempel:•Tekniska krav och hantering av GDPR•Krav på stödstrukturer, till exempel digitala verktyg, gott samarbete med VFU-sekretariatet för placeringar och med lärare i övriga kurser•Pedagogiska anpassningar av kursuppgifter och rutiner för samtalet•Studenters och lärares engagemang och medverkan i projektet•Att både få komma tillbaka till engagerade handledare, och att skala upp erfarenheter till att omfatta fler utbildningar
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| 22. |
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| 23. |
- Hamza, Karim, et al.
(författare)
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Förmåga 3 – innebörd och progressioner
- 2016
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Del 6 är den första av två delar som behandlar den tredje förmågan i kursplanerna för fysik, biologi och kemi, alltså att använda naturvetenskapens begrepp, modeller och teorier för att beskriva och förklara samband i naturen, samhället och människokroppen. Syftet med del 6 är att reflektera över innebörden av förmåga 3 för undervisning i år 1-3. Du ska också bekanta dig med en didaktisk modell för att skapa progression inom förmåga 3. Med progression menas här att bygga upp undervisningen så att eleverna får hjälp att successivt nå kursplanernas mål.
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| 24. |
- Hamza, Karim, et al.
(författare)
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Hybridization of practices in teacher-researcher collaboration
- 2018
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Ingår i: European Educational Research Journal. - : SAGE Publications. - 1474-9041. ; 17:1, s. 170-186
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we present experiences from a joint collaborative research project which may be described as an encounter between a school science teaching practice and a university science didactics research practice. We provide narratives which demonstrate how the encounter between these two communities of practice interacted to produce hybridization between the two in terms of mutual influences, resulting in the conceptual and practical development of both communities of practice. We argue that what happened in the project suggests one way of reducing the gap between educational research and teaching through the emergence of practices where the roles of teachers and researchers become blurred.
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| 25. |
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| 26. |
- Jansson, Leif, et al.
(författare)
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Pancreatic islet blood flow and its measurement
- 2016
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Ingår i: Upsala Journal of Medical Sciences. - : Uppsala Medical Society. - 0300-9734 .- 2000-1967. ; 121:2, s. 81-95
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Forskningsöversikt (refereegranskat)abstract
- Pancreatic islets are richly vascularized, and islet blood vessels are uniquely adapted to maintain and support the internal milieu of the islets favoring normal endocrine function. Islet blood flow is normally very high compared with that to the exocrine pancreas and is autonomously regulated through complex interactions between the nervous system, metabolites from insulin secreting beta-cells, endothelium derived mediators, and hormones. The islet blood flow is normally coupled to the needs for insulin release and is usually disturbed during glucose intolerance and overt diabetes. The present review provides a brief background on islet vascular function and especially focuses on available techniques to measure islet blood perfusion. The gold standard for islet blood flow measurements in experimental animals is the microsphere technique, and its advantages and disadvantages will be discussed. In humans there are still no methods to measure islet blood flow selectively, but new developments in radiological techniques hold great hopes for the future.
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| 27. |
- Jingryd, Ola, et al.
(författare)
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Sweden
- 2022
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Ingår i: Ways out of the European Housing Crisis. - : Edward Elgar Publishing. - 9781800377448 - 9781800377431 ; , s. 301-320
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Bokkapitel (refereegranskat)
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| 28. |
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| 29. |
- Kumar, Anmol, et al.
(författare)
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GDNF Overexpression from the Native Locus Reveals its Role in the Nigrostriatal Dopaminergic System Function
- 2015
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Ingår i: PLOS Genetics. - : PLoS. - 1553-7390 .- 1553-7404. ; 11:12
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Tidskriftsartikel (refereegranskat)abstract
- Degeneration of nigrostriatal dopaminergic system is the principal lesion in Parkinson's disease. Because glial cell line-derived neurotrophic factor (GDNF) promotes survival of dopamine neurons in vitro and in vivo, intracranial delivery of GDNF has been attempted for Parkinson's disease treatment but with variable success. For improving GDNF-based therapies, knowledge on physiological role of endogenous GDNF at the sites of its expression is important. However, due to limitations of existing genetic model systems, such knowledge is scarce. Here, we report that prevention of transcription of Gdnf 3'UTR in Gdnf endogenous locus yields GDNF hypermorphic mice with increased, but spatially unchanged GDNF expression, enabling analysis of postnatal GDNF function. We found that increased level of GDNF in the central nervous system increases the number of adult dopamine neurons in the substantia nigra pars compacta and the number of dopaminergic terminals in the dorsal striatum. At the functional level, GDNF levels increased striatal tissue dopamine levels and augmented striatal dopamine release and re-uptake. In a proteasome inhibitor lactacystin-induced model of Parkinson's disease GDNF hypermorphic mice were protected from the reduction in striatal dopamine and failure of dopaminergic system function. Importantly, adverse phenotypic effects associated with spatially unregulated GDNF applications were not observed. Enhanced GDNF levels up-regulated striatal dopamine transporter activity by at least five fold resulting in enhanced susceptibility to 6-OHDA, a toxin transported into dopamine neurons by DAT. Further, we report how GDNF levels regulate kidney development and identify microRNAs miR-9, miR-96, miR-133, and miR-146a as negative regulators of GDNF expression via interaction with Gdnf 3'UTR in vitro. Our results reveal the role of GDNF in nigrostriatal dopamine system postnatal development and adult function, and highlight the importance of correct spatial expression of GDNF. Furthermore, our results suggest that 3'UTR targeting may constitute a useful tool in analyzing gene function.
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| 30. |
- Lavett Lagerström, Malin, et al.
(författare)
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Planning for learning progressions with the didactical model organizing purposes : a study in context-based science teaching
- 2018
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Ingår i: NorDiNa. - : University of Oslo Library. - 1504-4556 .- 1894-1257. ; 14:3, s. 317-330
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Tidskriftsartikel (refereegranskat)abstract
- During the last years the didactical model organizing purposes has provided important insights about how teachers work with moment-to-moment learning progressions in science teaching. In the present study, organizing purposes were used to plan a lesson within a context-based unit in Biology, in which the Ebola disease was the overarching context. The lesson was planned in two parts. In the first part, the students worked with a model that simulated the spread of Ebola; in the second part, the model was discussed and compared with the real disease. The analysis of the enacted lesson shows that the students’ experiences from the model were effectively used by the teacher to establish a learning progression towards the learning goals. This was done by eliciting questions, comparisons between the model and real diseases, and recalling specific situations that allowed students to use everyday experiences and scientific concepts. Moreover, by maintaining focus in the context of the unit, the teacher through these actions, constantly directed the lesson towards the learning goals.
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| 31. |
- Lavett Lagerström, Malin, et al.
(författare)
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“Should we be afraid of Ebola?” A study of students’ learning progressions in context-based science teaching
- 2021
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Ingår i: NorDiNa. - : University of Oslo Library. - 1504-4556 .- 1894-1257. ; 17:1, s. 64-78
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we explored how learning progressions were established in a context-based science teaching unit. A science class in secondary school was followed during a teaching unit in Biology, in which the Ebola disease was used as context. Teaching was planned using the didactical model organizing purposes. Learning progressions were studied as continuity between teaching purposes, the science content and the context in four sequential lessons. The analysis of teaching evidenced a considerable variation in how learning progressions were constituted within lessons and showed how learning progressions could develop between lessons through the combination of different teaching activities. By consistently mentioning and referring to Ebola, the teacher had a pivotal role in establishing relations between teaching purposes, the content and the context. Furthermore, our results evidence the important role of the context in supporting students’ learning of science content. Finally, we discuss concrete actions in the planning of the unit to improve lessons that evidenced a weaker connection to the context.
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| 32. |
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| 33. |
- Levlin, Erik, et al.
(författare)
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Metoder för fosforåtervinning ur avloppsslam
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Fosfor är en globalt begränsad resurs som är viktig som näringsämne för livsmedelsförsörjningen. Kommunalt avloppsvatten innehåller stora mängder fosfor som idag inte återvinns och reningsprocessen är därmed att betrakta som en sänka för denna viktiga resurs. I denna rapport presenteras en utredning av status för tekniker och för återvinning av fosfor från kommunal avloppsvattenrening och vilka kostnader en återvinning medför. För återvinningen är användbarheten av den återvunna fosforprodukten grundläggande, vilket till stora delar är beroende av i vilken grad fosforprodukten kan renas från tungmetaller. Värdet av fosforprodukten bestäms dels av användbarheten för gödsling, dels av om den kan användas som råvara i fosfatindustrin. Det högsta ekonomiska värdet har produkter som är identiska med de fosforprodukter som idag tillverkas av fosfatindustrin och därmed har ett högt förädlingsvärde och stor efterfrågan. En mängd tekniker för fosforåtervinning har utvecklats och finns i allt från idéstadium och prototyp till drift i full skala. Kostnaderna varierar men är ofta höga i jämförelse med produktion av jungfrulig fosfor. Förutsättningar är också olika som till exempel skala för rimlig ekonomisk drift. I storskaliga anläggningar med slamförbränning synes rening av askan från tungmetaller och användning av askan som gödning vara en ekonomiskt tillämpbar teknik. Vid utvärdering av tekniker för återvinning av fosfor från kommunal vattenrening bör ett flertal faktorer tas hänsyn till. Kostnaden för upparbetning bör t.ex. vägas mot kostnaden för omhändertagande av slam. Viktiga är också krav på renhet, till exempel halt av tungmetaller som kadmium. Det är därför viktigt att belysa de alternativa behandlingsmetoderna ur ett systemperspektiv och utifrån det perspektivet vidare utveckla metoderna.
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| 34. |
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| 35. |
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| 36. |
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| 37. |
- Liss, Per, et al.
(författare)
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Iodinated contrast media decrease renomedullary blood flow. A possible cause of contrast media-induced nephropathy
- 2009
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Ingår i: Advances in Experimental Medicine and Biology. - Boston, MA : Springer US. - 0065-2598 .- 2214-8019. ; 645, s. 213-218
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Tidskriftsartikel (refereegranskat)abstract
- The renal medulla has been implicated as a key target for contrast media-induced nephropathy (CIN). Although the effects of contrast media (CM) on whole kidney blood flow are well characterized, the effect of CM on renal medullary blood flow has been controversial. It has been reported that an extremely high dose of a high osmolar CM (iothalamate; 2900 mg I/kg bw) injected rapidly increased the renal outer medullary blood flow (OMBF). However, more clinical relevant doses consistently result in a sustained decrease in medullary blood flow. Furthermore, simultaneous measurements using both laser-Doppler flowmetry and hydrogen washout yield similar results of a decrease in OMBF after CM administration. CM induced a transient 28% decrease in the laser-Doppler signal from the outer medulla, while the hydrogen washout rate in the same region was reduced by approximately 50%. Furthermore, CM administration consistently results in decreased medullary oxygen tension (PO2). The renal medulla works already during normal physiological conditions at the verge of hypoxia, and the majority of the studies published so far are in agreement with the hypothesis that CIN may have its origin in a further reduction in blood flow and/or oxygen availability of this region of the kidney.
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| 38. |
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| 39. |
- Ma, Le Anh, et al.
(författare)
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Na-ion mobility in P2-type Na0.5MgxNi0.17-xMn0.83O2 (0
- 2021
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Ingår i: Physical Chemistry Chemical Physics. - : Royal Society of Chemistry (RSC). - 1463-9084 .- 1463-9076. ; 23:42, s. 24478-24486
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Tidskriftsartikel (refereegranskat)abstract
- Sodium transition metal oxides with a layered structure are one of the most widely studied cathode materials for Na+-ion batteries. Since the mobility of Na+ in such cathode materials is a key factor that governs the performance of material, electrochemical and muon spin rotation and relaxation techniques are here used to reveal the Na+-ion mobility in a P2-type Na0.5MgxNi0.17-xMn0.83O2 (x = 0, 0.02, 0.05 and 0.07) cathode material. Combining electrochemical techniques such as galvanostatic cycling, cyclic voltammetry, and the galvanostatic intermittent titration technique with mu+SR, we have successfully extracted both self-diffusion and chemical-diffusion under a potential gradient, which are essential to understand the electrode material from an atomic-scale viewpoint. The results indicate that a small amount of Mg substitution has strong effects on the cycling performance and the Na+ mobility. Amongst the tested cathode systems, it was found that the composition with a Mg content of x = 0.02 resulted in the best cycling stability and highest Na+ mobility based on electrochemical and mu+SR results. The current study clearly shows that for developing a new generation of sustainable energy-storage devices, it is crucial to study and understand both the structure as well as dynamics of ions in the material on an atomic level.
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| 40. |
- Ma, Le Anh, 1992-, et al.
(författare)
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Na-ion mobility in P2-type Na0.5MgxNi0.17-xMn0.83O2 (0 <= x <= 0.07) from electrochemical and muon spin relaxation studies
- 2021
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Ingår i: Physical Chemistry, Chemical Physics - PCCP. - : Royal Society of Chemistry (RSC). - 1463-9076 .- 1463-9084. ; 23:42, s. 24478-24486
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Tidskriftsartikel (refereegranskat)abstract
- Sodium transition metal oxides with a layered structure are one of the most widely studied cathode materials for Na+-ion batteries. Since the mobility of Na+ in such cathode materials is a key factor that governs the performance of material, electrochemical and muon spin rotation and relaxation techniques are here used to reveal the Na+-ion mobility in a P2-type Na0.5MgxNi0.17-xMn0.83O2 (x = 0, 0.02, 0.05 and 0.07) cathode material. Combining electrochemical techniques such as galvanostatic cycling, cyclic voltammetry, and the galvanostatic intermittent titration technique with mu+SR, we have successfully extracted both self-diffusion and chemical-diffusion under a potential gradient, which are essential to understand the electrode material from an atomic-scale viewpoint. The results indicate that a small amount of Mg substitution has strong effects on the cycling performance and the Na+ mobility. Amongst the tested cathode systems, it was found that the composition with a Mg content of x = 0.02 resulted in the best cycling stability and highest Na+ mobility based on electrochemical and mu+SR results. The current study clearly shows that for developing a new generation of sustainable energy-storage devices, it is crucial to study and understand both the structure as well as dynamics of ions in the material on an atomic level.
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| 41. |
- Malmén, Linda, et al.
(författare)
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Åtgärder för att minska fosforutsläppen från befintliga enskilda avlopp
- 2004
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Litteraturgenomgången i rapporten bygger på en tidigare gjord genomgång (Palm m.fl., 2002) där litteratur fram till ca. år 2001 sammanfattats och denna har kompletterats med nytillkommen litteratur. Främst har kompletterande lösningar till markbäddar och infiltrationsanläggningar som finns som färdiga produkter, alternativt har testats i pilotskala, beaktats. I litteraturgenomgången ingår även referenser som rör funktionen hos markbäddar och infiltrationsanläggningar. Två huvudprinciper på kompletterande teknik har identifierats: I) tillsats av fällningskemikalier i flytande eller fast form och II) filter med fosforsorberande förmåga. Tekniken med tillsats av fällningskemikalier till avloppsvattnet finns som färdiga produkter på marknaden. Tekniken kan ge upp till 90 % fosforreduktion över anläggningen. Påfyllnad av kemikalier samt en extra slamtömning per år förutsätts för att tekniken ska fungera. Filter med fosforsorberande förmåga är produkter som håller på att testas och utvärderas, och därför finns de ännu inte ute på den svenska marknaden. Fosforreduktionen över anläggningen verkar kunna bli i samma storleksordning som för tillsats av fällningskemikalier, dvs. ca. 90 %. Arbetet vid installation och byte av filtermaterial är mer omfattande än vid tillsats av fällningskemikalier. Däremot går det flera år innan filtermaterialet behöver bytas. Därför behöver en totalbedömning av arbetsinsats och ingrepp göras för att kunna jämföra de bägge systemen med varandra. Framställningen av många fosforsorberande filtermaterial är mycket energikrävande, och det är nödvändigt att livscykelanalyser utförs för dessa material, samt en bedömning av dess lämplighet för jordbruksanvändning. Vid litteraturgenomgången inom detta projekt har inga resultat från fullskaleförsök med exempelvis halm eller torv som filtermaterial påträffats. Litteraturgenomgången pekar mot att väl anlagda markbäddar och infiltrationsanläggningar har en långsiktig reduktionsförmåga av fosfor på i storleksordningen 50 %. För nyare anläggningar finns indikationer i litteraturen att fosforreduktionen kan vara större. Resultatvariationerna i undersökningar av markbäddars och infiltrationsanläggningars funktion är stora. Troligen beror detta på svårigheten att få representativa prover från en anläggning i drift, samt att funktionen hos olika anläggningar varierar beroende på hur anläggningen är byggd. Kunskap saknas om vilken livslängd man kan förvänta sig av en markbädd eller infiltrationsanläggning som är anlagd enligt anvisningarna, och i rapporten diskuteras behovet av ett uppföljningssystem för att möjliggöra värdering av livslängden hos en specifik anläggning. I rapporten diskuteras även behov av ett sammanhållande kunskapscentrum för enskilda avlopp. Kunskapscentrum skulle kunna bidra till att stärka både myndigheter och enskilda fastighetsägare när enskilda avloppsanläggningar ska anpassas till miljöbalkens krav.
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| 42. |
- Matsubara, Nami, et al.
(författare)
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Cation Distributions and Magnetic Properties of Ferrispinel MgFeMnO4
- 2020
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Ingår i: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 59:24, s. 17970-17980
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Tidskriftsartikel (refereegranskat)abstract
- The crystal structure and magnetic properties of the cubic spinel MgFeMnO4 were studied by using a series of in-house techniques along with large-scale neutron diffraction and muon spin rotation spectroscopy in the temperature range between 1.5 and 500 K. The detailed crystal structure is successfully refined by using a cubic spinel structure described by the space group Fd3¯ m. Cations within tetrahedral A and octahedral B sites of the spinel were found to be in a disordered state. The extracted fractional site occupancies confirm the presence of antisite defects, which are of importance for the electrochemical performance of MgFeMnO4 and related battery materials. Neutron diffraction and muon spin spectroscopy reveal a ferrimagnetic order below TC = 394.2 K, having a collinear spin arrangement with antiparallel spins at the A and B sites, respectively. Our findings provide new and improved understanding of the fundamental properties of the ferrispinel materials and of their potential applications within future spintronics and battery devices.
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| 43. |
- Matsubara, Nami, et al.
(författare)
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Magnetism and ion diffusion in honeycomb layered oxide K 2Ni 2TeO 6
- 2020
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322 .- 2045-2322. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- In the quest for developing novel and efficient batteries, a great interest has been raised for sustainable K-based honeycomb layer oxide materials, both for their application in energy devices as well as for their fundamental material properties. A key issue in the realization of efficient batteries based on such compounds, is to understand the K-ion diffusion mechanism. However, investigation of potassium-ion (K+) dynamics in materials using e.g. NMR and related techniques has so far been very challenging, due to its inherently weak nuclear magnetic moment, in contrast to other alkali ions such as lithium and sodium. Spin-polarised muons, having a high gyromagnetic ratio, make the muon spin rotation and relaxation (μ+SR) technique ideal for probing ions dynamics in these types of energy materials. Here we present a study of the low-temperature magnetic properties as well as K+ dynamics in honeycomb layered oxide material K 2Ni 2TeO 6 using mainly the μ+SR technique. Our low-temperature μ+SR results together with complementary magnetic susceptibility measurements find an antiferromagnetic transition at TN≈ 27 K. Further μ+SR studies performed at higher temperatures reveal that potassium ions (K+) become mobile above 200 K and the activation energy for the diffusion process is obtained as Ea= 121 (13) meV. This is the first time that K+ dynamics in potassium-based battery materials has been measured using μ+SR. Assisted by high-resolution neutron diffraction, the temperature dependence of the K-ion self diffusion constant is also extracted. Finally our results also reveal that K-ion diffusion occurs predominantly at the surface of the powder particles. This opens future possibilities for potentially improving ion diffusion as well as K-ion battery device performance using nano-structuring and surface coatings of the particles.
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| 44. |
- Matsubara, Nami, et al.
(författare)
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Magnetism and ion diffusion in honeycomb layered oxide K2Ni2TeO6
- 2020
-
Ingår i: Scientific Reports. - : Springer Nature. - 2045-2322. ; 10:1
-
Tidskriftsartikel (refereegranskat)abstract
- In the quest for developing novel and efficient batteries, a great interest has been raised for sustainable K-based honeycomb layer oxide materials, both for their application in energy devices as well as for their fundamental material properties. A key issue in the realization of efficient batteries based on such compounds, is to understand the K-ion diffusion mechanism. However, investigation of potassium-ion (K+) dynamics in materials using e.g. NMR and related techniques has so far been very challenging, due to its inherently weak nuclear magnetic moment, in contrast to other alkali ions such as lithium and sodium. Spin-polarised muons, having a high gyromagnetic ratio, make the muon spin rotation and relaxation (mu+SR) technique ideal for probing ions dynamics in these types of energy materials. Here we present a study of the low-temperature magnetic properties as well as K+ dynamics in honeycomb layered oxide material K2Ni2TeO6 using mainly the mu+SR technique. Our low-temperature mu+SR results together with complementary magnetic susceptibility measurements find an antiferromagnetic transition at T-N approximate to 27 K. Further mu+SR studies performed at higher temperatures reveal that potassium ions (K+) become mobile above 200 K and the activation energy for the diffusion process is obtained as E-a = 121(13) meV. This is the first time that K+ dynamics in potassium-based battery materials has been measured using mu+SR. Assisted by high-resolution neutron diffraction, the temperature dependence of the K-ion self diffusion constant is also extracted. Finally our results also reveal that K-ion diffusion occurs predominantly at the surface of the powder particles. This opens future possibilities for potentially improving ion diffusion as well as K-ion battery device performance using nano-structuring and surface coatings of the particles.
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| 45. |
- Miniotaite, Ugne, et al.
(författare)
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Magnetic Properties of Multifunctional 7 LiFePO 4 under Hydrostatic Pressure
- 2023
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Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 2462:1
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Konferensbidrag (refereegranskat)abstract
- LiFePO4 (LFPO) is an archetypical and well-known cathode material for rechargeable Li-ion batteries. However, its quasi-one-dimensional (Q1D) structure along with the Fe ions, LFPO also displays interesting low-temperature magnetic properties. Our team has previously utilized the muon spin rotation (μ +SR) technique to investigate both magnetic spin order as well as Li-ion diffusion in LFPO. In this initial study we extend our investigation and make use of high-pressure μ +SR to investigate effects on the low-T magnetic order. Contrary to theoretical predictions we find that the magnetic ordering temperature as well as the ordered magnetic moment increase at high pressure (compressive strain).
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| 46. |
- Miniotaite, Ugne, et al.
(författare)
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Magnetic Properties of Multifunctional (LiFePO4)-Li-7 under Hydrostatic Pressure
- 2023
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Ingår i: Proceedings 15th International Conference on Muon Spin Rotation, Relaxation and Resonance (SR). - : IOP Publishing.
-
Konferensbidrag (refereegranskat)abstract
- LiFePO4 (LFPO) is an archetypical and well-known cathode material for rechargeable Li-ion batteries. However, its quasi-one-dimensional (Q1D) structure along with the Fe ions, LFPO also displays interesting low-temperature magnetic properties. Our team has previously utilized the muon spin rotation (mu+SR) technique to investigate both magnetic spin order as well as Li-ion diffusion in LFPO. In this initial study we extend our investigation and make use of high-pressure mu+SR to investigate effects on the low-T magnetic order. Contrary to theoretical predictions we find that the magnetic ordering temperature as well as the ordered magnetic moment increase at high pressure (compressive strain).
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| 47. |
- Nocerino, E., et al.
(författare)
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Magnetic nature of wolframite MgReO 4
- 2023
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Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 2462:1
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Konferensbidrag (refereegranskat)abstract
- Rhenium oxides belonging to the family AReO4 where A is a metal cation, exhibit interesting electronic and magnetic properties. In this study we have utilized the muon spin rotation/relaxation (μ +SR) technique to study the magnetic properties of the MgReO4 compound. To the best of our knowledge, this is the first investigation reported on this interesting material, that is stabilized in a wolframite crystal structure using a special high-pressure synthesis technique. Bulk magnetic studies show the onset of an antiferromagnetic (AF) long range order, or a possible singlet spin state at T C1 ≈ 90 K, with a subtle second high-temperature transition at T C2 ≈ 280 K. Both transitions are also confirmed by heat capacity (Cp ) measurements. From our μ +SR measurements, it is clear that the sample enters an AF order below T C1 = T N ≈ 85 K. We find no evidence of magnetic signal above T N, which indicates that T C2 is likely linked to a structural transition. Further, via sensitive zero field (ZF) μ +SR measurements we find evidence of a spin reorientation at T Cant ≈ 65 K. This points towards a transition from a collinear AF into a canted AF order at low temperature, which is proposed to be driven by competing magnetic interactions.
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| 48. |
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| 49. |
- Nocerino, Elisabetta, et al.
(författare)
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Magnetic nature of wolframite MgReO4
- 2023
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Ingår i: 15th International Conference on Muon Spin Rotation, Relaxation and Resonance, MuSR 2022. - : IOP Publishing.
-
Konferensbidrag (refereegranskat)abstract
- Rhenium oxides belonging to the family AReO4 where A is a metal cation, exhibit interesting electronic and magnetic properties. In this study we have utilized the muon spin rotation/relaxation (mu+SR) technique to study the magnetic properties of the MgReO4 compound. To the best of our knowledge, this is the first investigation reported on this interesting material, that is stabilized in a wolframite crystal structure using a special highpressure synthesis technique. Bulk magnetic studies show the onset of an antiferromagnetic (AF) long range order, or a possible singlet spin state at T-C1 approximate to 90 K, with a subtle second hightemperature transition at T-C2 approximate to 280 K. Both transitions are also confirmed by heat capacity (Cp) measurements. From our mu+SR measurements, it is clear that the sample enters an AF order below T-C1 = T-N approximate to 85 K. We find no evidence of magnetic signal above TN, which indicates that T-C2 is likely linked to a structural transition. Further, via sensitive zero field (ZF) mu(+) SR measurements we find evidence of a spin reorientation at T-Cant approximate to 65 K. This points towards a transition from a collinear AF into a canted AF order at low temperature, which is proposed to be driven by competing magnetic interactions.
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| 50. |
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