| 1. |
- Olsson, Sara, et al.
(författare)
-
A SEM study on the use of epoxy functional vegetable oil and reactive UV-absorber as UV-protecting pretreatment for wood
- 2015
-
Ingår i: Polymer degradation and stability. - : Elsevier BV. - 0141-3910 .- 1873-2321. ; 113:SI, s. 40-45
-
Tidskriftsartikel (refereegranskat)abstract
- The present study investigates the ageing performance of a UV protective system for wood, comprising the reactive UV absorber 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP) and epoxy functional vegetable oils (linseed and soybean oil). Scots pine samples of radial or cross-sectional surfaces were treated using a combination of the two components, or using only one of the oils. The treated samples were then aged in a Weather-Ometer for 2 x 60 h and analysed using VPSEM to follow the degradation of the wood substrate in the exact same spot before, during and after ageing. The results of the radial surfaces show slightly less degradation of samples treated with a combination of HEPBP and oil, and for the cross-sectional surfaces an even stronger protective effect is visible. For samples treated with only one of the two oils, no improvement was detectable. The radial surfaces were also analysed using FTIR where the results indicate presence of the protective treatment even after 120 h of exposure. Overall the combined pretreatment of HEPBP and epoxy functional linseed oil was concluded to have a photo-stabilising effect of the wood substrate.
|
|
| 2. |
- Olsson, Sara, et al.
(författare)
-
Covalently attached UV-absorbers for improved UV-protection of wood
- 2010
-
Ingår i: Proceedings of The Fifth European Conference on Wood Modification ECWM5. - : Latvian State Institute of Wood Chemistry.
-
Konferensbidrag (refereegranskat)abstract
- The present study describes the use of reactive UV-absorbers (UVAs) that can be covalently attached to a wood substrate to obtain an improved exterior durability. It has previously been demonstrated that the photostability of wood is increased if the UVA is grafted to the wood surface. The grafting of an epoxide-functional UVA, 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP), to thin veneer wood specimens had a larger photostabilizing effect than if the corresponding UVA without the reactive handle was added to the wood coating. The present study shows that not only the chemical structure of the UVA is important but also how the modification is performed i.e. the reaction procedure. A successful attachment of the UVA depends on both the reaction conditions as well as if other reactive species are present at the same time. The presence of for example a vegetable oil (epoxy functionalized soy bean oil) affects the grafting reaction of the UVA. Details on the effect of reaction conditions, reaction sequences, and presence of co-reactants will be presented.
|
|
| 3. |
- Olsson, Sara, 1984-
(författare)
-
Enhancing UV-protection of clear coated wood by utilizing reactive UV-absorber and epoxyfunctionalized soybean oil
- 2012
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This work presents the development of a new pretreatment for clear coated wood, that aims to increase the photoprotection of exterior wood products, and at the same time make the system more environmentally friendly. The pretreatment comprises the reactive UV absorber 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP), which has a primary epoxy group that can be covalently attached to the hydroxyl groups of the wood substrate. This reactant is accompanied by renewable epoxy functionalized soybean oil (ESBO), which contains a secondary epoxy group that also has the ability to react with the substrate and that promotes the compatibility between the two reactants. The ESBO further seems to have the advantage of increasing the flexibility of the pretreated veneers as well as decreasing the amount of water in the cell wall of the wood. The study was performed in two parts where the first part focused solely on the development and performance of the pretreatment, whereas the second part used the knowledge gained from part one to evaluate the pretreatment in combination with an acrylic clear coating. Grafting reactions were performed on thin wood veneers heated in solvent. In the first part the reaction parameters, temperature and reaction time, were varied to study their effects on the final properties of the pretreatments. The veneers where then analyzed using FTIR to determine if grafting was achieved. Results show that grafting was successful for reactions performed at temperatures above 90 °C. For part two, grafting was successful for both the boil- and dip process, indicating that a considerably shorter reaction time can be used. Samples from both part one and two where then exposed to accelerated ageing and the color change was measured to estimate the UV-resistance. The first part showed improved UV-resistance for some of the pretreatments, whereas the second part was more difficult to evaluate due to the top coat, but a slight improvement can be seen for samples using the pretreatment. A positive result for part two is also that the pretreatment do not appear to affect the adhesion between the substrate and the top coat. It is hence concluded that the proposed pretreatment is a possible way of increasing the photostability of exterior wood.
|
|
| 4. |
- Olsson, Sara, et al.
(författare)
-
Grafting of 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone and epoxidized soybean oil to wood : Reaction conditions and effects on the color stability of Scots pine
- 2012
-
Ingår i: Polymer degradation and stability. - : Elsevier BV. - 0141-3910 .- 1873-2321. ; 97:9, s. 1779-1786
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigates the photostabilizing effect of the reactive UV-absorber 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP) when used as a primer for wood. The present work further includes a study on the effect of HEPBP used in combination with an epoxy functionalized vegetable oil as a primer system. The study is based on reactions performed on pine veneers using 3-pentanone as a solvent and 4-(dimethylamino)pyridine (DMAP) as a catalyst, varying the reaction time and temperature. Results from FTIR and SEC measurements indicate that a desired reaction between HEPBP and wood does occur and that there are synergetic effects when HEPBP and oil are combined. Color measurements also indicate that the use of HEPBP and epoxidized soybean oil as pretreatment for wood results in a lower color change after 400 h of artificial weathering. We conclude that using HEPBP in combination with epoxy functionalized soybean oil does improve photostability of wood exposed to artificial weathering.
|
|
| 5. |
|
|
| 6. |
- Olsson, Sara, et al.
(författare)
-
Reactive UV-absorber and epoxy functionalized soybean oil for enhanced UV-protection of clear coated wood
- 2014
-
Ingår i: Polymer degradation and stability. - : Elsevier BV. - 0141-3910 .- 1873-2321. ; 110, s. 405-414
-
Tidskriftsartikel (refereegranskat)abstract
- The present work investigates the photostabilising effect of a pretreatment consisting of 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP) and epoxy functionalized soybean oil (ESBO), reacted on to Scots pine veneers coated with two different acrylic top coats. Two different pretreatment procedures were used, varying in reaction time and temperature. Results from FTIR and SEC analysis indicate that a large amount of reactant was present on the veneers after treatment with either of the two reaction procedures. Furthermore, coating of the pretreated surfaces was possible and the pretreatment does not seem to affect the adhesion between the coating and the wood substrate. Both accelerated ageing and natural exposure was used to study the resistance to photodegradation, and the results were analysed using colour measurements, FTIR and SEM. These analyses all show that 1400 h of accelerated ageing degrades neither the wood nor the coating to any larger extent. However, after 4000 h of UV exposure some signs of degradation are visible but to a lesser extent for pretreated samples. For the samples exposed to natural weathering during 14 months the performance was good in terms of photostabilisation, however all samples suffer from mould to different extents. Pretreated samples show smaller and more evenly distributed areas of mould compared to the references, which show slightly more mould. The combined coating/pretreatment system is thus assumed to have an effect in terms of photostabilization of the coated wood.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Bardage, Stig, et al.
(författare)
-
The effect of natural product treatment of southern yellow pine on fungi causing blue stain and mold
- 2014
-
Ingår i: International Biodeterioration & Biodegradation. - : Elsevier BV. - 0964-8305 .- 1879-0208. ; 86:B, s. 54-59
-
Tidskriftsartikel (refereegranskat)abstract
- Blue stain and mold growth on wood can be aesthetically unappealing, but mold growth can also potentially trigger health related issues. In this study, a screening of the effect of selected natural products and derivatives of natural products including essential oils, plant based monomers, and shellfish exoskeleton compounds on the inhibition of blue stain fungi and mold fungi in southern yellow pine veneers and cellulose filter paper. The treatment of the substrates, the weight percent gain of the natural products, and the inhibition effect is presented. The natural products have been investigated previously, but most have not been applied to wood or investigated with regards to blue stain or mold growth. The specimens were treated by dipping, wrapping in foil, and then heating at 105°C for 24h in order to encourage reaction or grafting of the natural products to the wood. A selection of seven additives each exhibited significant protection against blue stain colonization in Petri dish tests and these were studied more in-depth. These included tea tree oil, propyl gallate, hydrogenated gum oil, salicylic acid, cinnamon bark oil, butylene oxide, and furfural. The salicylic acid, tea tree oil, and cinnamon bark oil had the least amount of mold growth after four weeks in the mold chamber test, and have been previously reported to have a mechanism of antifungal activity resulting from their ability to disrupt the fungal cell wall. Propyl gallate veneer was the only specimen that had a lower pH and that would be considered unfavorable to mold growth. While furfural, salicylic acid, and cinnamon bark oil treated veneers all had more hydrophobic surfaces when compared to untreated wood.
|
|
| 11. |
|
|
| 12. |
- Blimark, Cecilie, et al.
(författare)
-
Melphalan 100mg/m(2) with stem cell support as first relapse treatment is safe and effective for myeloma patients with long remission after autologous stem cell transplantation.
- 2011
-
Ingår i: European journal of haematology. - : Wiley. - 1600-0609 .- 0902-4441. ; 87:2, s. 117-22
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: Today, a number of therapeutic options are available as the patient with myeloma relapses from initial treatment with high-dose melphalan and autologous stem cell transplantation (ASCT). For patients who experience a durable response to primary ASCT, retreatment with high-dose melphalan is recommended by many current guidelines. Yet, toxicity is an important aspect in the choice of relapse treatment, and a second ASCT in this setting could be associated with enhanced toxicity. As the goal for the treatment for relapsed myeloma should be disease control while maintaining quality of life, lower doses of melphalan might be preferable. Methods and Objectives: In this retrospective study, we account for the outcome of 66 patients with myeloma in first systemic relapse after ASCT, who were treated with intermediate-dose melphalan, 100mg/m(2) , and stem cell support (MEL 100). The aim was to evaluate this treatment in relation to prior response duration after initial ASCT and with respect to response rate, toxicity and survival. Results: The overall response rate was 62%. There was limited, mostly haematological, toxicity, and no treatment-related mortality was observed. The median progression-free survival (PFS) was 8.5months, and the median overall survival was 24months. Patients with time to progression of 34months or more (n=17; ≥75th percentile) after initial ASCT had a median PFS of 12.5months after MEL 100. Conclusion: For patients with a long-lasting response after ASCT, MEL 100 could be a therapeutic option with low toxicity and with efficacy comparable to newer immunomodulatory drugs.
|
|
| 13. |
|
|
| 14. |
- Brischke, C., et al.
(författare)
-
Modeling the material resistance of wood—part 2 : Validation and optimization of the meyer-veltrup model
- 2021
-
Ingår i: Forests. - : MDPI AG. - 1999-4907. ; 12:5
-
Tidskriftsartikel (refereegranskat)abstract
- Service life planning with timber requires reliable models for quantifying the effects of exposure-related parameters and the material-inherent resistance of wood against biotic agents. The Meyer-Veltrup model was the first attempt to account for inherent protective properties and the wetting ability of wood to quantify resistance of wood in a quantitative manner. Based on test data on brown, white, and soft rot as well as moisture dynamics, the decay rates of different untreated wood species were predicted relative to the reference species of Norway spruce (Picea abies). The present study aimed to validate and optimize the resistance model for a wider range of wood species including very durable species, thermally and chemically modified wood, and preservative treated wood. The general model structure was shown to also be suitable for highly durable materials, but previously defined maximum thresholds had to be adjusted (i.e., maximum values of factors accounting for wetting ability and inherent protective properties) to 18 instead of 5 compared to Norway spruce. As expected, both the enlarged span in durability and the use of numerous and partly very divergent data sources (i.e., test methods, test locations, and types of data presentation) led to a decrease in the predictive power of the model compared to the original. In addition to the need to enlarge the database quantity and improve its quality, in particular for treated wood, it might be advantageous to use separate models for untreated and treated wood as long as the effect of additional impact variables (e.g., treatment quality) can be accounted for. Nevertheless, the adapted Meyer-Veltrup model will serve as an instrument to quantify material resistance for a wide range of wood-based materials as an input for comprehensive service life prediction software. © 2021 by the authors.
|
|
| 15. |
- Brischke, C., et al.
(författare)
-
Modelling the material resistance of wood—Part 3 : Relative resistance in above and in ground situations—Results of a global survey
- 2021
-
Ingår i: Forests. - : MDPI AG. - 1999-4907. ; 12:5
-
Tidskriftsartikel (refereegranskat)abstract
- Durability-based designs with timber require reliable information about the wood properties and how they affect its performance under variable exposure conditions. This study aimed at utilizing a material resistance model (Part 2 of this publication) based on a dose–response approach for predicting the relative decay rates in above-ground situations. Laboratory and field test data were, for the first time, surveyed globally and used to determine material-specific resistance dose values, which were correlated to decay rates. In addition, laboratory indicators were used to adapt the material resistance model to in-ground exposure. The relationship between decay rates in-and above-ground, the predictive power of laboratory indicators to predict such decay rates, and a method for implementing both in a service life prediction tool, were established based on 195 hardwoods, 29 softwoods, 19 modified timbers, and 41 preservative-treated timbers. © 2021 by the authors..
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
- Burström, Mats, 1962-, et al.
(författare)
-
Nutida landskap, modern industri och förorter står nu på tur
- 2000
-
Ingår i: Kulturmiljövård. - Stockholm : Riksantikvarieämbetet. - 1100-4800. ; :1, s. 64-67
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Vid en eventuell översyn av riksintresseområden ter det sig naturligt att lyfta fram landskapets kulturvärden i ett mångvetenskapligt perspektiv, liksom att kartlägga 1900-talets industri- och kommunikationsmiljöer. Andra miljöer att lyfta fram är efterkrigstidens förorter.
|
|
| 19. |
|
|
| 20. |
|
|
| 21. |
- De Vetter, Liesbeth, et al.
(författare)
-
Combined evaluation of durability and ecotoxicity : A case study on furfurylated wood
- 2009
-
Ingår i: Wood Material Science & Engineering. - 1748-0272 .- 1748-0280. ; 4:1-2, s. 30-36
-
Tidskriftsartikel (refereegranskat)abstract
- Modified wood is commercially available and merchandized as a new, environmentally friendly and durable wood species. However, there are no standards focusing on the evaluation of modified wood. Combining resistance against fungal decay and good ecotoxicological properties may be a start. In this study softwood and hardwood species were furfurylated using different treatment processes and treating solutions. The durability was determined by exposing the treated wood to a range of Basidiomycetes and the ecotoxicity was studied on two aquatic organisms. It was the purpose to come to a strategy and how to unite efficacy and ecotoxicity, since this is important in product development. The results show that the selection of fungus used for mass loss determination and the choice of ecotoxicity method is decisive, confirming that a combination of methods is valuable. A tiered approach to find the optimal treatment seems the best option. First, adequate protection against wood-rotting fungi should be attained, followed by ecotoxicity evaluation of the wood leachates. If necessary, the optimization process should be repeated until both durability and ecotoxicity are within satisfactory limits. This process could be extended with other evaluation criteria, e.g. dimensional stability of the modified wood or a risk analysis of its leachate.
|
|
| 22. |
|
|
| 23. |
- Ekstrand, Åsa, et al.
(författare)
-
Homogeneous WC–Co-Cemented Carbides from a Cobalt-Coated WC Powder Produced by a Novel Solution-Chemical Route
- 2007
-
Ingår i: Journal of The American Ceramic Society. - : Wiley. - 0002-7820 .- 1551-2916. ; 90:11, s. 3449-3454
-
Tidskriftsartikel (refereegranskat)abstract
- A solution chemical route to cobalt-coated WC-powder is described that allows for the preparation of WC–Co powders and compacts having a carbon content very close to the desired carbon content even under an inert atmosphere. The microstructural homogeneity in the sintered WC–Co composites when using the Co-coated grains was found to be superior as compared with conventionally mill-mixed powders, and the structural changes in the individual WC-grains were found to be much smaller, which is ascribed mainly to the fact that the coated grains do not require a grinding step leading to the formation of a tail of smaller WC grain sizes.
|
|
| 24. |
- Ekstrand, Åsa, et al.
(författare)
-
Processing of ZnO-based varistors using oxide, alkoxide, nitrato-alkoxide and carboxylato precursors
- 1997
-
Ingår i: Journal of Sol-Gel Science and Technology. - 0928-0707 .- 1573-4846. ; 8:1-3, s. 697-701
-
Tidskriftsartikel (refereegranskat)abstract
- We have investigated the preparation of ZnO varistors by different chemical solution routes with the aim of improving the homogeneity of the phases formed and to obtain a better control of microstructure. One conventional oxide mixing route and four solution chemical routes have been used to prepare the precursor materials. In all cases, the same composition (mol%) was used; ZnO (95.9), Bi2O3 (1), Sb2O3 (1), NiO (1), Co2O3 (0.5), MnO (0.5), Cr2O3 (0.1). The same sintering procedure was also applied. It was found that the precursor materials consisting of ZnO grains covered by a thin film of the additive oxides yielded smaller ZnO grains. Also the microstructure in the final compacts was improved, compared with that of compacts prepared from oxide mixing routes. The smaller ZnO grain size in the final compacts was attributed to the presence of spinel grains. The spinel grains are formed at lower temperatures and, when they reach a size of 1 μm, they hinder the growth of ZnO grains.
|
|
| 25. |
|
|
| 26. |
- Epmeier, Hannah, et al.
(författare)
-
Bending creep performance of modified timber
- 2007
-
Ingår i: European Journal of Wood and Wood Products. - : Springer Berlin / Heidelberg. - 0018-3768 .- 1436-736X. ; 65:5
-
Tidskriftsartikel (refereegranskat)abstract
- The present study is a supplement to Epmeier and Kliger (2005), which investigated the effect of three different modification methods (acetylation, modification with methylated melamine resin and heat treatment in vegetable oil) on four material properties (density, modulus of elasticity (MOE), creep deflection and relative creep) and their inter-relations. In this study, another modification method (furfurylation) and four additional material parameters (“relative stiffness”, i.e. MOE/density, moisture content, change in moisture content and anti-creep efficiency) and their correlations are included. In addition, the creep curves were analysed to assess the development of bending creep performance. The properties were assessed by experimental work on 132 specimens of Scots pine sapwood with dimensions of 45×70×1100 mm3. It was found that modification leads to significant changes in material properties. Furfurylation increases density and reduces creep deflection, relative creep and moisture content. Modified timber tends to deflect and creep significantly less than untreated timber. However, the extent of reduction in relative creep appears not to be related to the extent of reduction in creep deflection. Initial deflection and/or modulus of elasticity are suitable for predicting the creep deflection of untreated and modified timber.
|
|
| 27. |
|
|
| 28. |
|
|
| 29. |
- Epmeier, Hannah, 1971, et al.
(författare)
-
Differently modified wood: comparison of some selected properties
- 2004
-
Ingår i: Scandinavian Journal of Forest Research. ; 19:Supplement 5, s. 31-37
-
Tidskriftsartikel (refereegranskat)abstract
- To turn wood into a material with enhanced and less varied properties, many methods of chemical modification have been developed in the past few decades. In this work, the mechanical and physical properties of wood modified using nine methods were studied. The modification methods were acetylation, maleoylation, succinylation, furfurylation, modification with N-methylol acryl amide, modification with reactive linseed oil derivative, modification with methylated melamine resin, thermal modification in vegetable oil, and a combination of acetylation and modification with methylated melamine resin. The wood species used were Scots pine (Pinus sylvestris L.), beech (Fagus sylvatica L.) and birch (Betula pubescens Ehrh.). Both pure sapwood and heartwood specimens of pine were used. The following properties were studied: equilibrium moisture content, strength and stiffness in different climates, stiffness stabilization efficiency, antiswelling efficiency, impact bending strength and hardness. Acetylation and furfurylation were the most effective modification methods for achieving high dimensional stability, high stiffness stability and low equilibrium moisture content. The impact strength was reduced by all the methods, but to a varying extent. Acetylation, furfurylation and modification with methylated melamine formaldehyde resin led to a slight increase in bending strength. Furfurylation at high degrees of modification resulted in a substantial increase in hardness.
|
|
| 30. |
|
|
| 31. |
|
|
| 32. |
- Germovsek, Eva, et al.
(författare)
-
A Time-to-Event Model Relating Integrated Craving to Risk of Smoking Relapse Across Different Nicotine Replacement Therapy Formulations
- 2021
-
Ingår i: Clinical Pharmacology and Therapeutics. - : John Wiley & Sons. - 0009-9236 .- 1532-6535. ; 109:2, s. 416-423
-
Tidskriftsartikel (refereegranskat)abstract
- Smoking increases the risk of cancer and other diseases, causing an estimated 7 million deaths per year. Nicotine replacement therapy (NRT) reduces craving for smoking, therefore, increasing an individual's probability to remain abstinent. In this work, we for the first time quantitatively described the relationship between craving and smoking abstinence, using retrospectively collected data from 19 studies, including 3 NRT formulations (inhaler, mouth spray, and patch) and a combination of inhaler and patch. Smokers motivated to quit were included in the NRT or placebo arms. Integrated craving (i.e., craving over a period of time) was assessed with 4-category, 5-category, or 100-mm visual analogue scale. The bounded integer model was used to assess latent craving from all scales. A time-to-event model linked predicted integrated craving to the hazard of smoking relapse. Available data included 9,323 adult subjects, observed for 3 weeks up to 2 years. At the study end, 9% (11% for NRT and 5% for placebo), on average, remained abstinent according to the protocol definition. A Gompertz-Makeham hazard best described the data, with a hazard of smoking relapse decreasing over time. Latent integrated craving was positively related to the hazard of smoking relapse, through a sigmoidal maximum effect function. For the same craving, being on NRT was found to reduce the hazard of relapse by an additional 30% compared with placebo. This work confirmed that low craving is associated with a high probability of remaining smoking abstinent and that NRT, in addition to reducing craving, increases the probability of remaining smoking abstinent.
|
|
| 33. |
|
|
| 34. |
- Germovsek, Eva, et al.
(författare)
-
Relating Nicotine Plasma Concentration to Momentary Craving Across Four Nicotine Replacement Therapy Formulations
- 2020
-
Ingår i: Clinical Pharmacology and Therapeutics. - : WILEY. - 0009-9236 .- 1532-6535. ; 107:1, s. 238-245
-
Tidskriftsartikel (refereegranskat)abstract
- Tobacco use is a major health concern. To assist smoking cessation, nicotine replacement therapy (NRT) is used to reduce nicotine craving. We quantitatively described the relationship between nicotine pharmacokinetics (PKs) from NRTs and momentary craving, linking two different pharmacodynamic (PD) scales for measuring craving. The dataset comprised retrospective data from 17 clinical studies and included 1,077 adult smokers with 39,802 craving observations from four formulations: lozenge, gum, mouth spray, and patch. A PK/PD model was developed that linked individual predicted nicotine concentrations with the categorical and visual analogue PD scales through a joint bounded integer model. A maximum effect model, accounting for acute tolerance development, successfully related nicotine concentrations to momentary craving. Results showed that all formulations were similarly effective in reducing craving, albeit with a fourfold lower potency for the patch. Women were found to have a higher maximal effect of nicotine to reduce craving, compared with men.
|
|
| 35. |
|
|
| 36. |
|
|
| 37. |
|
|
| 38. |
|
|
| 39. |
|
|
| 40. |
- Jonsson, Rickard, 1971-
(författare)
-
Blatte betyder kompis : Om maskulinitet och språk i en högstadieskola
- 2007
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis deals with masculinity and language among a group of teenage boys. Based on a year’s fieldwork at a middle school in a Stockholm suburb, the study focuses on how language is used to “perform” masculinity and how the stereotype of the “immigrant youth” emerges in daily communication in school. Inspired by contemporary theoretical work on gender and performativity, the thesis argues that “immigrant youth” is a subject position that emerges through the intersection of two related kinds of phenomena: (a) what particular individuals do with language, and (b) the attitudes and practices about “immigrant young men” present in society and communicated in the school environment. There is an ongoing debate about how youths in multiethnic suburbs speak poor Swedish and use inappropriate language. This thesis takes a critical stance toward the essentializing and moralizing dimensions of that debate. It explores how discussions about “suburban youth slang” and “sexist language” contribute to stereotypes about “immigrant youth” that demonize young men from immigrant backgrounds, even as they subtly work to establish the superiority and desirability of middle-class ethnic Swedish culture and people. In addition, the study examines the way in which communicative practices in the school constantly refer to a particular masculine position that function as an “absent presence” in the construction of “immigrant male youth”, namely the “fag”. The omnipresent threat of the “fag” works in particular ways to construct both a normative Swedishness and a normative heterosexual masculinity. These stereotypes emerge as important boundaries for what should not be said or done in everyday school life. The role of different categorizations in school is examined, and a main finding is that there are no fixed meanings of words as “immigrant” or “blatte” (darkie/immigrant). The labels may be used in processes of exclusion, but they are also in order to establish social relations and friendships among boys.
|
|
| 41. |
|
|
| 42. |
- Kihlman, Martin, 1986-
(författare)
-
Dissolution of cellulose for textile fibre applications
- 2012
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis forms part of a project with the objective of developing and implementing a novel, wood-based, process for the industrial production of cellulose textile fibres. This new process should not only be cost effective but also have far less environmental impact then current processes. Natural and man-made fibres are usually plagued with problems (e.g. economic and environmental) and are unsuitable in meeting growing demands. The focus of this thesis was therefore to investigate the dissolution of cellulose derived from various pulps in novel aqueous solvent systems. It was shown that cellulose could be dissolved in a NaOH/H2O solvent at low temperatures (<0°C) and that such an alkaline solvent can be improved regarding the solubility, stability and rheological properties of the cellulose dopes formed if different additives (salts or amphiphilic molecules) are used. The effect of different kinds of pretreatment (individually and combined) and the influence of pulp properties on cellulose accessibility and dissolution were also evaluated. These pretreatments affected, as expected, some characteristic properties of the pulps mainly by reducing the DP but also, for example, changing the composition of the carbohydrates. Not only did the pretreatment affect the solubility it also increased the stability of the cellulose dopes, resembling the effect of chemical additives to the NaOH system. According to multivariate data analysis it was established that, of the pulp properties analyzed, only the composition of carbohydrates and the DP had a significant influence on the solubility of the pulps used in this study. Finally, it was emphasized that the dissolution of cellulose pulps seemed to be controlled by a very complex interaction between both kinetic and thermodynamic parameters.
|
|
| 43. |
|
|
| 44. |
- Knutsson, Hans, et al.
(författare)
-
Representing local structure using tensors II
- 2011
-
Ingår i: Proceedings of the 17th Scandinavian conference on Image analysis. - Berlin, Heidelberg : Springer. - 9783642212260 - 9783642212277 ; , s. 545-556
-
Konferensbidrag (refereegranskat)abstract
- Estimation of local spatial structure has a long history and numerous analysis tools have been developed. A concept that is widely recognized as fundamental in the analysis is the structure tensor. However, precisely what it is taken to mean varies within the research community. We present a new method for structure tensor estimation which is a generalization of many of it's predecessors. The method uses filter sets having Fourier directional responses being monomials of the normalized frequency vector, one odd order sub-set and one even order sub-set. It is shown that such filter sets allow for a particularly simple way of attaining phase invariant, positive semi-definite, local structure tensor estimates. We continue to compare a number of known structure tensor algorithms by formulating them in monomial filter set terms. In conclusion we show how higher order tensors can be estimated using a generalization of the same simple formulation.
|
|
| 45. |
- Knutsson, Hans, et al.
(författare)
-
Structure Tensor Estimation : Introducing Monomial Quadrature Filter Sets
- 2012
-
Ingår i: New Developments in the Visualization and Processing of Tensor Fields. - Berlin, Heidelberg : Springer. - 9783642273421 ; , s. 3-28
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- "Bringing together key researchers in disciplines ranging from visualization and image processing to applications in structural mechanics, fluid dynamics, elastography, and numerical mathematics, the workshop that generated this edited volume was the third in the successful Dagstuhl series. Its aim, reflected in the quality and relevance of the papers presented, was to foster collaboration and fresh lines of inquiry in the analysis and visualization of tensor fields, which offer a concise model for numerous physical phenomena. Despite their utility, there remains a dearth of methods for studying all but the simplest ones, a shortage the workshops aim to address. Documenting the latest progress and open research questions in tensor field analysis, the chapters reflect the excitement and inspiration generated by this latest Dagstuhl workshop, held in July 2009. The topics they address range from applications of the analysis of tensor fields to purer research into their mathematical and analytical properties. They show how cooperation and the sharing of ideas and data between those engaged in pure and applied research can open new vistas in the study of tensor fields."--Publisher's website.
|
|
| 46. |
|
|
| 47. |
|
|
| 48. |
- Larsson Brelid, Pia, et al.
(författare)
-
Acetylated wood – Results from long-term field tests
- 2007
-
Ingår i: The Third European Conference on Wood Modification.. - : BC.
-
Konferensbidrag (refereegranskat)abstract
- The effectiveness of acetylation as a method to increase the durability of wood has been demonstrated in several studies over the last sixty years, starting with pioneers like Tarkow, Stamm and Goldstein. Nevertheless, as acetylated wood has now reached large scale production, the importance of long term-field test data on the performance of acetylated wood has increased. Firstly, this paper will address a project started in 1991, where acetylated Scots pine is tested in a full EN 252 test. The test is still running in Nordic NWPC test fields, Simlångsdalen in Sweden and in Viikki, Finland. The results show that irrespectively of test field, pine wood test stakes with an acetylation level of about 22% (expressed as acetyl content) were as durable as the CCA treated wood at a high retention level (10.3 kg/m3) after 15 years in ground contact. Secondly, acetylated wood (acetyl content 22%) is also being evaluated under marine conditions in Kristineberg on the Swedish west coast, according to EN 275 (marine borer resistance). The test has been running since 1999 and the X-ray rating shows a slight attack by marine borers after eight years in test, whereas the untreated controls failed after only one year. If the acetylation (acetyl content 21%) is followed by a post treatment with melamine resin (weight gain 19%) no attack could be observed after eight years. Thirdly, coated acetylated pine panels were exposed on rigs 45º facing south for 13 years, according to an early version of EN 927-3 in Ultuna and Malmö. The results indicate that acetylated wood in combination with a proper coating system, gives a considerably longer service life of the panels as compared to coated unmodified panels.
|
|
| 49. |
|
|
| 50. |
|
|
