1234567 51 - 100 of 1059
Cite
Citation style
• apa
• harvard1
• ieee
• modern-language-association-8th-edition
• vancouver
• Other style
More styles
Language
• de-DE
• en-GB
• en-US
• fi-FI
• nn-NO
• nn-NB
• sv-SE
• Other locale
More languages
Output format
• html
• text
• asciidoc
• rtf
• Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Ordbok över folkmålen i övre Dalarna: Häfte 23, M(j)ölningshus-MölaII1984Book (Other academic)
• Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Ordbok över folkmålen i övre Dalarna: Häfte 22, Mackaberus-M(j)ölning1983Book (Other academic)
• Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Ordbok över folkmålen i övre Dalarna: Häfte 21, Ljutfågel-Lövåma1982Book (Other academic)
• Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Ordbok över folkmålen i övre Dalarna: Häfte 20, Labb-Ljute1981Book (Other academic)
• Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Ordbok över folkmålen i övre Dalarna: Häfte 19, illustrationer. G-K1980Book (Other academic)
• Public defence: 2017-06-12 13:00 V1, STOCKHOLM
KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
Modelling phosphorus dynamics in constructed wetlands upgraded with reactive filter media2017Licentiate thesis, comprehensive summary (Other academic)

Phosphorus mobility and sorption mechanisms underlying the removal efficiency of different adsorbent media were evaluated using the SWAT model and 3Dreactive transport model. The aims of the thesis were to: i) improve understanding of phosphorus mobility in the Oxundaån catchment; ii) identify suitable sites for constructing wetlands; iii) develop the numerical reactive transport model in order to identify key parameters which affects sorption efficiencies of the reactive adsorbent media; iv) predict the media's sorption efficiencies; and v) evaluate the viable reactive adsorbent media for mitigating eutrophication in the Baltic Sea. To predict phosphorus removal efficiencies of the adsorbent media and visualize the sorption process within the constructed wetlands, a three-dimensional model was developed within the COMSOL Multiphysics®. The reactive transport model was developed by coupling four physics interfaces to simulate the processes of water flow dynamics, transport of diluted phosphorus species, reaction kinetics and heat transfer in the porous media. The SWAT modelling results showed that arable land with the less background phosphorus retention, lower soil permeability and lower land slope could provide suitable sites for constructing wetlands. The simulated phosphorus sorption efficiency of the reactive filter media was ranked: 88 % (113 g P kg-1) for Polonite®, 85 % (81gP kg-1) for Filtralite P®, 62 % (61 gPkg-1) for Blast furnace slag, 57 % (44gP kg-1) for Wollastonite. In comparison to other media, Polonite® was observed to be a suitable reactive adsorbent media for wetland applications under different hydraulic loading rates and pH change, whose P-removal efficiency last for six years. Moreover, the modelling results showed less significant effects of particle size on the phosphorus removal efficiency as compared to solution pH and Ca mineral content. Precipitation was identified to be the dominant mechanisms for phosphorus removal in these media with the positive correlation to pH increase (R2 = 0.94, p-value = 0.002) and Calcium content (R2 = 0.73, p-value = 0.004). The good agreements between the simulated outputs and experimental data accurately captured the processes of phosphorus mobility and removal. The results suggest that the reactive transport models are valuable tools for providing insight into sorption processes in subsurface systems and improving design criteria for constructed wetlands. More experimental data are needed to calibrate the sensitivity of local parameters in order to better assess the performance of subsurface flow constructed wetlands.

• Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Ordbok över folkmålen i övre Dalarna: Häfte 18, Kvarndygn-Kövis1980Book (Other academic)
• Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Ordbok över folkmålen i övre Dalarna: Häfte 17, Kolpa-Kvarndel1979Book (Other academic)
• Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Ordbok över folkmålen i övre Dalarna: Häfte 16, Klabbmölja-Kolp1977Book (Other academic)
• Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Ordbok över folkmålen i övre Dalarna: Häfte 15, Jaga-Klabbklubbe1977Book (Other academic)
• Public defence: 2017-06-14 13:15 Hörsal 2, Uppsala
Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
Creating value from science: Interaction between academia, business and healthcare in the Uppsala PET Centre case2017Doctoral thesis, monograph (Other academic)

Recent decades have seen greater focus, both national and global, on universities’ role in boosting economic growth. Besides teaching and conducting research, universities are urged to contribute directly to the economy by commercialising research findings and interacting with industry.

This thesis explores the dynamics and effects of such interplay by concentrating on a particular case of interaction involving Uppsala University, Uppsala University Hospital and a large multinational corporation. More specifically, the aim of the study was to investigate how use of science and value creation from science are affected when actors belonging to disparate spheres interact closely. The thesis recounts the evolution of the Uppsala PET Centre, established as a University research institute in 1989, which has served both as a site for pre-clinical and clinical research and as an important resource in routine clinical work. The whole Centre was commercialised when a large firm acquired it in 2002, only to be decommercialised and returned to the University and the University Hospital less than a decade later.

Using a network perspective, this thesis analyses the journey of the Uppsala PET Centre by studying interfaces between physical and organisational resources. The basic argument is that to understand the effects of inter-sphere interaction on science use, one must consider the materiality of science and differences between the interacting actor spheres in terms of preferences, norms and goals – ‘schemes of valuation’ in the present work. The study shows that the materiality of science has a restrictive impact on flexibility of science use, and different actors’ simultaneous use of science is therefore severely constrained. Because of these constraints, the actor spheres involved struggle to control physical scientific resources in ways aligned with their particular schemes of valuation. Sharing, turn-taking and efforts to separate overlapping use contexts become the means of managing the restricted scope for science use.

Further, this thesis demonstrates that while interfaces containing physical resources are controllable and always result in some kind of value (albeit not necessarily on the scale expected), the outcomes of combinations of organisational resources connected with disparate schemes of valuation are impossible to anticipate and control.

The thesis concludes that there are reasons to rethink our expectations of the short-term economic and social effects of university–industry interaction, a complicated affair that encompasses opportunities and unforeseeable challenges alike.

• Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
Ordbok över folkmålen i övre Dalarna: Häfte 14, Hårdnacke-Jag1976Book (Other academic)
• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 12, Gälma-Hejd1973Book (Other academic)
• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 11, Granlöp-Gällsol1971Book (Other academic)
• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
• RISE - Research Institutes of Sweden, Safety and Transport, Safety.
RISE - Research Institutes of Sweden, Safety and Transport, Safety.
New models for calculating maximum gas temperatures in large tunnel fires2016Report (Other academic)

The work presented in this report focuses on estimating maximum gas temperatures at ceiling level during large tunnel fires. Gas temperature is an important parameter to consider when designing the fire resistance of a tunnel structure. Earlier work by the authors has established correlations between excess ceiling gas temperature and effective tunnel height, ventilation rate, and heat release rate. The maximum possible excess gas temperature was set as 1350°C, independent of the tunnel structure and local combustion conditions. As a result of this research, two models have been developed to better estimate possible excess maximum gas temperatures for large tunnel fires in tunnels with differing lining materials and structure types (e.g. rock, concrete). These have been validated using both model- and full-scale tests. Comparisons of predicted and measured temperatures show that both models correlate well with the test data. However, Model I is better and more optimal, due to the fact that it is more conservative and easier to use. The fire duration and flame volume are found to be related to gas temperature development. In reality, the models could also be used to estimate temperatures in a fully developed compartment fire.

• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 9, illustrationer. A-F1970Book (Other academic)
• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 8, Fubbla-Föttling1968Book (Other academic)
• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 7, FjäreIII-Fubbig1968Book (Other academic)
• Public defence: 2017-06-14 10:00 B2, Stockholm
KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Physical Metallurgy.
Formation of Bainite in Steels2017Doctoral thesis, comprehensive summary (Other academic)

A systematic survey of morphology of bainite and proeutectoid ferrite was carried out in order to validate some old thoughts of bainite transformation mechanism. It is confirmed that there is no morphological evidence supporting a sharp change neither between Widmanstätten ferrite and the ferritic component of upper bainite, nor between upper and lower bainite. Both Widmanstätten ferrite and upper bainite start with precipitation of ferrite plates at a grain boundary while lower bainite starts with intragranular nucleation. In case of grain boundary nucleation, a group of parallel plates with same crystallographic orientation to the parent austenite grain forms. This process is followed by a second stage of decomposition of the austenitic interspace, which remained in between the primary ferrite plates. At high temperature, the austenitic interspace would either retain as thin slabs or transform into pearlite through a nodule originated from a grain boundary. At lower temperature, cementite precipitation starts to be possible and initiates simultaneous growth of ferrite. Generally, there are two modes of such eutectoid reactions operating in the second stage, i.e. a degenerate and a cooperative mode, which would lead to typical upper and lower bainite, respectively, in definition of carbides morphology. Both upper and lower bainite according to this definition are observed in a wide temperature range. A sharp temperature between the upper and lower bainite structures thus exists only when the definition is based on their nucleation sites, i.e. grain boundary nucleation for upper bainite and intragranular nucleation for lower bainite. Supposing that the first stage is a diffusionless process it should have a high growth rate to prevent carbon diffusion. This is not supported by lengthening rate obtained in current study as well as data from literature for Fe-C alloys. Finally, it is shown that the “subunits” play no role in the lengthening process of bainite.

• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 6, Dölsk-Fjäre1966Book (Other academic)
• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 5, Disk-Dölja1965Book (Other academic)
• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 4, Bröstkrave-Dishorn1964Book (Other academic)
• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 3, Bogsera-Bröstsjuka1963Book (Other academic)
• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 2, Barka-Bogräs1962Book (Other academic)
• Mälardalens Högskola.
Folkhälsoutbildning i entreprenörskap –kan en pantomat bli en del avsamhällsutvecklingen?2016In: Socialmedicinsk Tidskrift, ISSN 0037-833X, no 5, 604-611 p.Article in journal (Refereed)

”You can do things and make a difference”. This article will give you an insightin how a social innovation can serve as a case study in an undergraduatecourse in entrepreneurship within health and welfare at Mälardalensuniversity. Students can become active participants in their learning bypedagogical approaches that invites them to feel that they do can make achange. In this article you will learn how to combine the work of a real lifecase study and an active social entrepreneur with pedagogical methods thatseek to awake and activate students in their learning process. During twosessions the students are on a journey that illustrate the initial idea of how toimprove the social determinates from health in the local community to implementchanges that make a difference for health. The students are also askedto give feedback on improvements of the social innovation at hand.

• Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Institute for Language and Folklore, Uppsala landsmålsarkiv (ULMA).
Ordbok över folkmålen i övre Dalarna: Häfte 1, A-Barka1961Book (Other academic)
• Kristianstad University, Learning Resource Centre.
Högskolepedagogisk debatt: Läraktiviteter för att uppnå värderingsförmåga och förhållningssätt2017Collection (editor) (Other (popular science, discussion, etc.))
• Public defence: 2017-06-15 10:00 M311, Stockholm
KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
Enhanced image analysis, a tool for precision metrology in the micro and macro world2017Doctoral thesis, comprehensive summary (Other academic)

The need for high speed and cost efficient inspection in manufacturing lineshas led to a vast usage of camera-based vision systems. The performance ofthese systems is sufficient to determine shape and size, but hardly to an accuracylevel comparable with traditional metrology tools. To achieve highprecision shape/position/defect measurements, the camera techniques haveto be combined with high performance image metrology techniques whichare developed and adapted to the manufactured components. The focus ofthis thesis is the application of enhanced image analysis as a tool for highprecision metrology. Dedicated algorithms have been developed, tested andevaluated in three practical cases ranging from micro manufacturing at submicronprecision to meter sized aerospace components with precision requirementsin the 10 μm range.The latter measurement challenge was solved by low cost standard consumerproducts, i.e. digital cameras in a stereo configuration and structured lightfrom a gobo-projector. Combined with high-precision image analysis and anew approach in camera calibration and 3D reconstruction for precise 3Dshape measurement of meter sized surfaces, the achievement was fulfilledand verified by two conventional measurement systems; a high precisioncoordinate measurement machine and a laser scanner.The sub-micron challenge was the implementation of image metrology forverification of micro manufacturing installations within a joint Europeaninfrastructure network, EUMINAfab. The results were an unpleasant surprisefor some of the participating laboratories, but became a big step forwardto improve the dimensional accuracy of the investigated laser micromachining, micro milling and micro-printing systems, since the accuracy ofthese techniques are very difficult to assess.The third high precision metrology challenge was the measurement of longrange,low-amplitude topographic structures on specular (shiny) aerodynamicsurfaces. In this case Fringe Reflection Technique (FRT) was appliedand image analysis algorithms were used to evaluate the fringe deformationas a measure of the surface slopes to obtain high resolution data. The resultwas compared with an interferometric analysis showing height deviation inthe range of tens of micrometers over a lateral extension of several cm.

• Public defence: 2017-06-14 09:15 Room 2005, Uppsala
Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
Non-aqueous Electrolytes and Interfacial Chemistry in Lithium-ion Batteries2017Doctoral thesis, comprehensive summary (Other academic)

Lithium-ion battery (LIB) technology is currently the most promising candidate for power sources in applications such as portable electronics and electric vehicles. In today's state-of-the-art LIBs, non-aqueous electrolytes are the most widely used family of electrolytes. In the present thesis work, efforts are devoted to improve the conventional LiPF6-based electrolytes with additives, as well as to develop alternative lithium 2-trifluoromethyl-4,5-dicyanoimidazole (LiTDI)-based electrolytes for silicon anodes. In addition, electrode/electrolyte interfacial chemistries in such battery systems are extensively investigated.

Two additives, LiTDI and fluoroethylene carbonate (FEC), are evaluated individually for conventional LiPF6-based electrolytes combined with various electrode materials. Introduction of each of the two additives leads to improved battery performance, although the underlying mechanisms are rather different. The LiTDI additive is able to scavenge moisture in the electrolyte, and as a result, enhance the chemical stability of LiPF6-based electrolytes even at extreme conditions such as storage under high moisture content and at elevated temperatures. In addition, it is demonstrated that LiTDI significantly influences the electrode/electrolyte interfaces in NMC/Li and NMC/graphite cells. On the other hand, FEC promotes electrode/electrolyte interfacial stability via formation of a stable solid electrolyte interphase (SEI) layer, which consists of FEC-derivatives such as LiF and polycarbonates in particular.

Moreover, LiTDI-based electrolytes are developed as an alternative to LiPF6 electrolytes for silicon anodes. Due to severe salt and solvent degradation, silicon anodes with the LiTDI-baseline electrolyte showed rather poor electrochemical performance. However, with the SEI-forming additives of FEC and VC, the cycling performance of such battery system is greatly improved, owing to a stabilized electrode/electrolyte interface.

This thesis work highlights that cooperation of appropriate electrolyte additives is an effective yet simple approach to enhance battery performance, and in addition, that the interfacial chemistries are of particular importance to deeply understand battery behavior.

• Stockholm University, Faculty of Science, Department of Physics.
Resonances in three-body systems2014Licentiate thesis, monograph (Other academic)

Three particles interacting via Coulomb forces represents a fundamental problem in quantum mechanics whose approximate solution provides some insight into the more complex analysis associated with few-body problems. We have investigated resonance states composed of three particles interacting via Coulombic and more general potentials in non-relativistic quantum mechanics, using the complex scaling method. My calculations have been applied to two different physical systems: (i) an investigation of the possibility of resonances in the $p e \mu$ system, which has been suggested as a possible reason for unexpected results from a recent measurement of the proton radius in muonic hydrogen (ii) a calculation of resonances in positron-hydrogen scattering, which shows that we can represent this system with the accuracy needed for future scattering calculations. The basis set used is built from Gaussians in Jacobi coordinates, thus automatically including mass-polarisation effects which cannot be neglected in muonic systems.

• Stockholm University, Faculty of Science, Department of Physics.

The use of Stereotactic Radiation Therapy (SRT) employing one large fraction of radiation, as in stereotactic radiosurgery (SRS), or few fractions of high doses, has continuously increased due to the technical development and the progress in dose delivery complemented by the positive clinical experience. The success of stereotactic radiation therapy depends on many clinical, dosimetric and radiobiological factors. For SRS in particular, the delivery of a highly conformal dose distribution to the target in one fraction allowing at the same time the sparing of the normal tissue and the critical structures is part of the basic concept of the technique. Provided that the highly accurate radiosurgical equipment available today is used, planning and delivering the prescribed dose distribution is an achievable goal, and therefore the main issue to be solved is the definition of the target. As the target volume in radiosurgery is usually defined without margins, the success of the stereotactic approach critically depends on the accurate delineation of the target which could be identified as a factor of key importance. In addition, the delineation of the Organs At Risk (OAR) is also critical.

The purpose of this work was to evaluate the current degree of variability for target and OAR contouring and to establish methods for analysing multi-observer data regarding structure delineation variability.

A multi-center target and OAR delineation study was initiated. Two complex and six common cases to be treated with SRS were selected and subsequently distributed to centers around the world performing Gamma Knife® radiosurgery for delineation and treatment planning. The resulting treatment plans and the corresponding delineated structures were collected and analysed.

Results showed a very high variability in contouring for four complex radiosurgery targets. Similar results indicating high variability in delineating the OAR and reporting the doses delivered to them were also reported. For the common radiosurgery targets however, a higher agreement in the delineation was observed, although lower than expected.

The assessment of the quality of treatment planning for radiosurgery is usually performed with respect to the coverage of the target, the planning specificity, and dose to the sensitive structures and organs close to the target. However, physical dose conformity to the target does not guarantee the success of the treatment. The assessment of the plan quality should also be performed with respect to the clinical outcome expressed as probability of controlling the target that should be irradiated. In this respect, this study also aimed to create the framework for assessing the impact of the inaccuracy in delineating the target on the predicted treatment outcome for radiosurgery targets known for their high potential to invade the neighbouring normal tissue, using radiobiological models. In addition, radiobiological models have also been used to determine the tumour control probability accounting for the oxygenation for stereotactic radiation therapy targets.

The results suggest that radiobiological modelling has the potential to add to the current knowledge in SRS by theoretically assessing the key factors that might influence the treatment outcome.

• Stockholm University, Faculty of Science, Department of Physics.
Chiral Recognition by Means of Mass Spectrometry2016Licentiate thesis, comprehensive summary (Other academic)

This thesis is based on experimental studies of chiral ions in the gas-phase. An electrospray ion source platform (Stockholm University) and a commercially available quadrupole time-of-flight mass spectrometer (University of Oslo) have been used in our studies.

Using the advantages of tandem mass spectrometry, we have investigated interactions between protonated amino acids, namely phenylalanine (Phe), tryptophan (Trp), and methionine (Met), and Trp containing diastereomeric complexes with chiral (2-butanol) and achiral (argon) targets. In high energy collisions of 1 keV in the center-of-mass (c.o.m.) frame, collision induced dissociation (CID) via multiple channels independent on the chirality of either the projectile or the target was observed. The fragmentation via loss of H2O + CO and NH3 were found to be the main reaction channels for all of the studied amino acids. The energy gained in the collision was found to be sufficient to initiate fragmentation via various competitive reaction pathways.

Chiral recognition in CID of the diastereomeric proton-bound complexes of tryptophan and 2-butanol as a function of collision energy with argon was studied. Stereo dependent dissociation of the complexes was observed, and for the first time an energy dependence has been measured for such a complex. Where possible, comparisons with previously reported results have been performed.

• Stockholm University, Faculty of Science, Department of Physics.

States of matter with quasi-particle excitations that exhibit anyonic statisticsare of great theoretical interest, especially in those cases where the anyons arenon-Abelian. Two of the most promising states that could support non-Abeliananyons are the ν = 5/2 quantum Hall state and the two dimensional p-wavesuperconductor, and they can both be understood as p-wave paired states. Themotivation for the present thesis is to get a better understanding of the theo-retical description of p-wave paired states.In the accompanying paper we construct an effective field theory for the 2Dspin-less p-wave paired superconductor that faithfully describes the topologicalproperties of the bulk state, and also provides a model for the subgap statesat vortex cores and edges. In particular it captures the topologically protectedzero modes and has the correct ground state degeneracy on the torus. Wealso show that our effective field theory becomes a topological field theory in awell defined scaling limit and that the vortices have the expected non-Abelianbraiding statistics.

• Stockholm University, Faculty of Science, Department of Physics.
Zero-Field Splitting in Gd(III) complexes: Towards a molecular understanding of paramagnetic relaxation2015Licentiate thesis, comprehensive summary (Other academic)

The prime objectives of contrast agents in Magnetic Resonance Imaging(MRI) is to accelerate the relaxation rate of the solvent water protons in the surrounding tissue. Paramagnetic relaxation originates from dipole-dipole interactions between the nuclear spins and the fluctuating magnetic field induced by unpaired electrons. Currently Gadolinium(III) chelates are the most widely used contrast agents in MRI, and therefore it is incumbent to extend the fundamental theoretical understanding of parameters that drive the relaxation mechanism in these complexes.

Traditionally the Solomon-Bloembergen-Morgan equations have been utilized to describe relaxation times in terms, primarily of the Zeeman interaction, which is the splitting of degenerate energy levels due to an applied magnetic field. However, in compounds such as Gadolinium(III) complexes with total electron spins higher than 1 (in this case S=7/2) other interactions such as the Zero-Field Splitting(ZFS) play a significant role. ZFS is the splitting of degenerate energy levels in the absence of an external magnetic field. For this purpose, the current research delves into an understanding of the relaxation process, focusing on ZFS in various complexes of interest, using quantum chemical methods as well as molecular dynamic simulations.

• Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Vienna, Austria.
Institute for Sustainable Economic Development, University of Natural Resources and Life Sciences, Vienna, Austria. Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
Using long term synthetic time series to assess the impact of meteorological extreme events on renewable energy systems: a case study of wind and hydro power in Sweden2017In: Geophysical Research Abstracts, ISSN 1029-7006, E-ISSN 1607-7962, Vol. 19, EGU2017-14131Article in journal (Other academic)

Synthetic time series of renewable energy generation provide important inputs for energy system models that study the transition to low carbon energy systems. The coverage of national energy statistics is usually too short or temporal resolution too low – in particular if meteorological extreme events should be assessed. These extreme events may put high stress on power systems with very high shares of renewables and therefore have to be studied in detail. We use simulated time series of Swedish wind energy generation for a 35 year period based on MERRA reanalysis datasets. The simulation of hydropower generation is more complex and requires hydrological models that combine precipitation data with spatially explicit information on soil type and land cover to simulate river discharge. For this purpose, we use time series of daily river discharge that have been simulated using the open source model HYPE (HYdrological Predictions for the Environment).

We compared the derived time series for wind and hydropower generation in the four Swedish bidding areas with respect to their long-term correlation, patterns of seasonality, and length and duration of extreme events. Preliminary results show that expanding wind power capacities could significantly reduce the overall variability of renewable energy generation. Furthermore, the frequency and duration of extreme production events in a combined wind-hydropower system is lower than in a hydropower system only. Further work will study the need for backup capacities in a future Swedish power system with very high shares of hydro, wind and solar power (>90%).

• Public defence: 2017-06-09 09:30 FB54, Stockholm
Stockholm University, Faculty of Science, Department of Physics.
Phenomenological Studies of Neutrinos2017Licentiate thesis, comprehensive summary (Other academic)
• Umeå universitet.
Sociologisk Forskning 2003:32003Collection (editor) (Refereed)
• Stockholm University, Faculty of Science, Department of Physics.
Nanocalorimetry of electronic phase transitions in systems with unconventional superconductivity and magnetic ordering2015Licentiate thesis, comprehensive summary (Other academic)

In this thesis, low temperature specific heat measurements on small (μg) single crystals of different superconducting and magnetic systems are presented. The device used in this work features a combination of high sensitivity and good accuracy over the temperature range 1-400 K and allows measurements in high magnetic fields. It consists of a stack of thin films deposited in the center of a Si3N4 membrane. A batch process for the production of up to 48 calorimeters from a 2" silicon wafer was developed in order to overcome the scarcity of devices and allow systematic investigations. With abundance of calorimeters, single crystals of three different systems were studied.

Fe2P is the parent compound of a broad family of magnetocaloric materials. The first-order para- to ferromagnetic phase transition at TC = 216 K was investigated for fields H up to 2 T, applied parallel and perpendicular to the easy axis of magnetization c. Strikingly different phase contours were obtained depending on the field direction. In particular, for H perpendicular to c, two different ferromagnetic phases, with magnetization parallel and perpendicular to c are found. It was also possible to observe the superheating/supercooling states, the latent heat, and the structural change associated to the first-order transition.

BaFe2(As1-xPx)2 is a member of the recently discovered iron-based high-temperature superconductors family. Crystals with three different compositions were measured to study the doping dependence of the superconducting properties in the overdoped regime (x > 0.30). The electronic specific heat at low temperatures was analyzed with a two band α model, which allows to extract the gap amplitudes and their weights. The degree of gap anisotropy was investigated from in-field measurements. Additional information on the system was obtained by a combined analysis of the condensation energy and upper critical field.

URu2Si2, a heavy fermion material, was studied around and above the hidden-order temperature THO = 17.5 K. The origin of the hidden-order phase is still not understood. High-resolution specific heat data were collected to help clarify if any pseudogap state is seen to exist above THO. We found no evidence for any bulk phase transition above THO.

• Språk- och folkminnesinstitutet.
Språk- och folkminnesinstitutet. Språk- och folkminnesinstitutet. Språk- och folkminnesinstitutet. Språk- och folkminnesinstitutet.
Ordbok över Sveriges dialekter. Band 1: Häfte 3, ³Arsa-¹Back2000Book (Other academic)
• Nyström, Gunnar
Ordbok över Sveriges dialekter. Band 1: Häfte 2, Andvarpning-²Arsa1994Book (Other academic)
• Karlstad University, Faculty of Social and Life Sciences, Centre for the Studies of Social Sciences Didactics.
Att begripliggöra det förflutna: En studie av hur åtta historielärare i samtal och planering föreställer sig historieundervisning inriktad mot att motverka fragmentering2017Licentiate thesis, monograph (Other academic)

Fragmentation refers to the difficulties that students face when attempting to utilise substantive knowledge to make a useable big picture of the past. What possibilities are there to prevent fragmentation, within the framework of regular history teaching in school? In this thesis I tackle this question with interest in teaching methods proposed by history teachers.

The research project is designed with the intention to provide the participating teachers with “reasonably good conditions” to be able to form an opinion about the problem of fragmentation. In the research project the participating teachers take part of litterature from the research field of history teaching, and processing the problem of fragmentation through discussion in focus groups and through planning of a history course.

In this study I investigate how eight history teachers, given “reasonably good conditions”, imagine feasible teaching in order to prevent fragmentation within the frames of a History 1a1 course. Three research objects are being investigated. What are the teachers´ views regarding: 1) efficient teaching to prevent fragmentation? 2) the framework of teaching? 3) a History course that is including an action plan in order to prevent fragmentation?

The study shows that the teachers experience limited possibilities to conduct efficient teaching to prevent fragmentation within the frames of a History 1a1-course. The teachers still, regardless of these limitations, find it possible to conduct strategically focused teaching to prevent fragmentation. The teaching strategies presented by the teachers can be more or less significant and the teachers are not necessarily prepared to allot time and resources to these strategies. Feasible teaching in order to prevent fragmentation is not necessarily associated with strategically aimed teaching.

• SMHI, Research Department, Oceanography.
SMHI, Research Department, Oceanography. SMHI, Research Department, Oceanography.
Nutrient transports in the Baltic Sea - results from a 30-year physical-biogeochemical reanalysis2017In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 14, no 8, 2113-2131 p.Article in journal (Refereed)
SMHI, Research Department, Climate research - Rossby Centre. SMHI.
The interactions between soil-biosphere-atmosphere (ISBA) land surface model multi-energy balance (MEB) option in SURFEXv8-Part 2: Introduction of a litter formulation and model evaluation for local-scale forest sites2017In: Geoscientific Model Development, ISSN 1991-959X, E-ISSN 1991-9603, Vol. 10, no 4, 1621-1644 p.Article in journal (Refereed)
• Public defence: 2017-06-12 13:15 Sal D3, Stockholm
KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
First-Principles Study on Electronic and Optical Properties of Copper-Based Chalcogenide Photovoltaic Materials2017Doctoral thesis, comprehensive summary (Other academic)

To accelerate environmentally friendly thin film photovoltaic (PV) technologies, copper-based chalcogenides are attractive as absorber materials. Chalcopyrite copper indium gallium selenide (CIGS ≡ CuIn1–xGaxSe2) is today a commercially important PV material, and it is also in many aspects a very interesting material from a scientific point of view. Copper zinc tin sulfide selenide (CZTSSe ≡ Cu2ZnSn(S1–xSex)4) is considered as an emerging alternative thin film absorber material. Ternary Cu2SnS3 (CTS) is a potential absorber material, thus its related alloys Cu2Sn1–xGexS3 (CTGS) and Cu2Sn1–xSixS3 (CTSS) are attractive due to the tunable band gap energies. CuSb(Se1–xTex)2 and CuBi(S1–xSex)2 can be potential as ultra-thin (≤ 100 nm) film absorber materials in the future. In the thesis, analyses of these Cu-based chalcogenides are based on first-principles calculations performed by means of the projector augmented wave method and the full-potential linearized augmented plane wave formalisms within the density functional theory as implemented in the VASP and WIEN2k program packages, respectively.

The electronic and optical properties of CIGS (x = 0, 0.5, and 1) are studied, where the lowest conduction band (CB) and the three uppermost valence bands (VBs) are parameterized and analyzed in detail. The parameterization demonstrates that the corresponding energy dispersions of the topmost VBs are strongly anisotropic and non-parabolic even very close to the Γ-point. Moreover, the density-of-states and constant energy surfaces are calculated utilizing the parameterization, and the Fermi energy level and the carrier concentration are modeled for p-type CIGS. We conclude that the parameterization is more accurate than the commonly used parabolic approximation. The calculated dielectric function of CuIn0.5Ga0.5Se2 is also compared with measured dielectric function of CuIn0.7Ga0.3Se2 collaborating with experimentalists. We found that the overall shapes of the calculated and measured dielectric function spectra are in good agreement. The transitions in the Brillouin zone edge from the topmost and the second topmost VBs to the lowest CB are responsible for the main absorption peaks. However, also the energetically lower VBs contribute significantly to the high absorption coefficient.

CTS and its related alloys are explored and investigated. For a perfectly crystalline CTS, reported experimental double absorption onset in dielectric function is for the first time confirmed by our calculations. We also found that the band gap energies of CTGS and CTSS vary almost linearly with composition over the entire range of x. Moreover, those alloys have comparable absorption coefficients with CZTSSe. Cu2XSnS4 (X = Be, Mg, Ca, Mn, Fe, Ni, and Zn) are also studied, revealing rather similar crystalline, electronic, and optical properties. Despite difficulties to avoid high concentration of anti-site pairs disordering in all compounds, the concentration is reduced in Cu2BeSnS4 partly due to larger relaxation effects. CuSb(Se1–xTex)2 and CuBi(S1–xSex)2 are suggested as alternative ultra-thin film absorber materials. Their maximum efficiencies considering the Auger effect are ~25% even when the thicknesses of the materials are between 50 and 300 nm.

• Public defence: 2017-06-07 10:15 E2, Stockholm
KTH, School of Engineering Sciences (SCI), Mechanics, Stability, Transition and Control.
Wind turbine simulations using spectral elements2017Licentiate thesis, comprehensive summary (Other academic)

Understanding the flow around wind turbines is a highly relevant research question due to the increased interest in harvesting energy from renewable sources. This thesis approaches the topic by means of numerical simulations using the actuator line method and the incompressible Navier–Stokes equations in the spectral element code Nek5000. The aim is to gain enhanced understanding of the wind turbine wake structure and wind turbine wake interaction. A verification study of the method and implementation is performed against the finite volume solver EllipSys3D using two types of turbines, an idealized constant circulation turbine and the Tjæreborg turbine. It is shown that Nek5000 requires significantly lower resolution to accurately compute the wake development, however, at the cost of a smaller time step.The constant circulation turbine is investigated further with the goal of establishing guidelines for the use of the actuator line method in spectral element codes, where the mesh is inherently non-equidistant and currently used guidelines of force distribution based on Gaussian kernels are difficult to apply. It is shown that Nek5000 requires a larger kernel width in the fixed frame of reference to remove numerical instabilities. Further, the impact of different Gaussian widths on the wake development is investigated in the rotating frame of reference, showing that the convection velocity and the breakdown of the spiral tip and root vortices are dependent on the Gaussian width. In the second part, the flow around single and multiple wind-turbine setups at different operating conditions is investigated and compared with experimental results. The focus is placed on comparing the power and thrust coefficients and the wake development based on the time-averaged streamwise velocity and turbulent stresses. Further the influence of the tower model is investigated both upstream and downstream of the turbine. The results show that the wake is captured accurately in most cases. The loading exhibits a significant dependence on the Reynolds number at which the airfoil data is extracted. When the helical tip vortices are stable the turbulent stresses at the tip vortices are underestimated in the numerical simulations. This is due to the finite resolution and the projection of the actuator line forces in the numerical domain using a prescribed Gaussian width, which leads to lower induced velocities in the helical vortices.

• Public defence: 2017-06-15 09:30 Air-Fire, Science for Life Laboratories, Solna
KTH, School of Engineering Sciences (SCI), Applied Physics, Cellular Biophysics.
High-resolution imaging of kidney tissue samples2017Licentiate thesis, comprehensive summary (Other academic)

The kidney is one of the most important and complex organs in the human body, filtering hundreds of litres of blood daily. Kidney disease is one of the fastest growing causes of death in the modern world, and this motivates extensive research for better understanding the function of the kidney in health and disease. Some of the most important cellular structures for blood filtration in the kidney are of very small dimensions (on the sub-200 nm scale), and thus electron microscopy has been the only method of choice to visualize these minute structures. In one study, we show for the first time that by combining optical clearing with STED microscopy, protein localizations in the slit diaphragm of the kidney, a structure around 75 nanometers in width, can now be resolved using light microscopy. In a second study, a novel sample preparation method, expansion microscopy, is utilized to physically expand kidney tissue samples. Expansion improves the effective resolution by a factor of 5, making it possible to resolve podocyte foot processes and the slit diaphragm using confocal microscopy. We also show that by combining expansion microscopy and STED microscopy, the effective resolution can be improved further. In a third study, influences on the development of the kidney were studied. There is substantial knowledge regarding what genes (growth factors, receptors etc.) are important for the normal morphogenesis of the kidney. Less is known regarding the physiology behind how paracrine factors are secreted and delivered in the developing kidney. By depleting calcium transients in explanted rat kidneys, we show that calcium is important for the branching morphogenesis of the ureteric tree. Further, the study shows that the calcium-dependent initiator of exocytosis, synaptotagmin, is expressed in the metanephric mesenchyme of the developing kidney, indicating that it could have a role in the secretion of paracrine growth factors, such as GDNF, to drive the branching.

• Public defence: 2017-06-13 09:00 Sal M235, Stockholm
KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
District Heating-driven Membrane Distillation for Water Purification in Industrial Applications2017Doctoral thesis, monograph (Other academic)

Domestic and industrial water demands are growing globally due to population growth and rapid economic development, placing increasing strains on water resources. Wastewater effluents generated from these and other activities impact the environment and are thus subject to tightening regulation. The focus of research and development in water treatment processes aims at both pollutant removal efficiency and cost of purification.

Membrane distillation (MD) is a developing thermally driven technology capable of achieving extremely high environmental performance utilizing renewable energy sources to a high degree. District heating networks, and in particular those driven by biomass, represent an ideal heat supply for MD systems.

This thesis presents a technoeconomic assessment of district heating driven MD for water purification in selected industrial applications. The study covers analysis of MD separation performance and the related costs from different district heating integration scenarios. The analyses are based on three types of semi-commercial MD modules, with experiments conducted at laboratory and pilot scales. The case studies include pharmaceutical residue removal from effluents of municipal wastewater treatment plant, wastewater purification in pharmaceutical industry, and ethanol concentration in bioethanol production plant. Full-scale simulation studies were carried out for the identified case studies based on the experimental data obtained from MD module along with process information gathered from the industries. Results from the pharmaceutical residue removal pilot trials showed very good to excellent separation efficiency for 37 compounds at feed concentrations ranging from ng/L to mg/L. From alcohol-water feeds, ethanol concentrations were increased from 5% to nearly 90%. Simulation studies revealed that district heating integration of MD systems is feasible. Costs per unit volume of purified water are higher than competing technologies, however the configurations enable enhanced environmental performance that would be difficult to achieve otherwise.

• Public defence: 2017-06-13 13:00 N360, Umeå
Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education. Umeå University, Faculty of Social Sciences, Umeå Centre for Gender Studies (UCGS).
Utanför experimentlådan: kunskapsproduktion, tid och materia i förskolans naturvetenskapsundervisning2017Doctoral thesis, comprehensive summary (Other academic)

The aim of this thesis is to contribute knowledge on conditions for science teaching in preschool. While Swedish preschool practices commonly build on children’s subjective experiences, scientific knowledge production is often associated with objectivity and detachedness. Seen from that perspective, tensions may occur when the knowledge cultures of preschool and science meet, as when science teaching is implemented in preschool. This thesis seeks to explore issues that are crucial for teachers to negotiate when they implement science teaching in preschool.

The thesis includes five articles that build on empirical data in the form of teachers’ talk (interviews, focus group discussion, project meetings) and observation data from preschool practice. The data analyses draw on various theoretical perspectives, including communities of practice and feminist critique of science as well as theoretical concepts connected to framing and agential realism.

The main result is that it is crucial, to teachers’ implementation of science teaching in preschool, that science content is open to children’s contributions. Further, the results show that teachers integrate several different forms of knowledge production when working with science content in practice. For example, observations and systematic investigations are combined with imagination and children’s bodily experiences. This goes against the presumed tensions between the knowledge cultures of preschool and science. However, tensions between the knowledge cultures are indicated by teachers’ unwillingness to interfere with children’s investigative processes or ideas about science content by relating children’s ideas to scientific explanatory models. Seen from a teacher’s perspective, it appears to be unproblematic to leave children’s ideas about science content unresolved, compared to leaving children’s ideas about social relations and other content unresolved.

Drawing on the results, I discuss teaching beyond the limited material and temporal dimensions of the science box, which emerges as a metaphor when teachers describe a way of teaching that they are not comfortable with. Further, I suggest that the concept working theories, which addresses children’s tentative ideas about relations in their surrounding world, be introduced in preschool science teaching, to ease the perceived conflict between children’s ideas about science and scientific explanatory models.

v. 2.24.1
|