| 1. |
- Linton, Gabriel, 1982-
(författare)
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Entrepreneurial orientation : reflections from a contingency perspective
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Entrepreneurship has been argued to be a key driver of the economy by creating jobs, turning inventions to innovations, and also improving the overall standard of life. A firm’s entrepreneurial orientation (EO) indicates the degree to which a firm is entrepreneurial. However, there are several different approaches to conceptualizing the EO concept and its sub-dimensions, frequently described as innovativeness, risk taking, and proactiveness. The role of the sub-dimensions is not quite clear in the EO literature. Furthermore, many studies claim that firms can increase their performance simply by increasing their EO, while this thesis draws upon contingency theory to argue that EO needs to be aligned with—‘fit’ the internal and external context, if the firm is to perform well. Thus, this thesis aims to advance the conceptualization of EO by problematizing the core construct and also discussing how EO can fit with context. The thesis consists of four papers in which the EO concept is elaborated on and contingency theory is applied to construct conceptual models of the interaction between EO and different contexts, which are also empirically investigated. Furthermore, the sub-dimensions of EO are discussed in terms of their meanings and measurement to point out their individual impact on the EO.The overall findings indicate that EO is not as simple a concept as often portrayed in the EO literature. Rather, EO is more complex in the ways that it can fit with internal and external context and, on these bases, it is suggested that ideal types of EO and context is a way forward for research in the area. Additionally, it is argued that EO as a theoretical construct may not only be conceptualized as an overall entrepreneurial attribute (which is common in the extant literature), but also as a complex and granular attribute.
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| 2. |
- Reyier, Sofia, 1980-
(författare)
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Bonding Ability Distribution of Fibers in Mechanical Pulp Furnishes
- 2008
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis presents a method of measuring the distribution of fiber bonding ability in mechanical pulp furnishes. The method is intended for industrial use, where today only average values are used to describe fiber bonding ability, despite the differences in morphology of the fibers entering the mill. Fiber bonding ability in this paper refers to the mechanical fiber’s flexibility and ability to form large contact areas to other fibers, characteristics required for good paper surfaces and strength. Five mechanical pulps (Pulps A-E), all produced in different processes from Norway spruce (Picea Abies) were fractionated in hydrocyclones with respect to the fiber bonding ability. Five streams were formed from the hydrocyclone fractionation, Streams 1-5. Each stream plus the feed (Stream 0) was fractionated according to fiber length in a Bauer McNett classifier to compare the fibers at equal fiber lengths (Bauer McNett screens 16, 30, 50, and 100 mesh were used). Stream 1 was found to have the highest fiber bonding ability, evaluated as tensile strength and apparent density of long fiber laboratory sheets. External fibrillation and collapse resistance index measured in FiberLabTM, an optical measurement device, also showed this result. Stream 5 was found to have the lowest fiber bonding ability, with a consecutively falling scale between Stream 1 and Stream 5. The results from acoustic emission measurements and cross-sectional scanning electron microscopy analysis concluded the same pattern. The amount of fibers in each hydrocyclone stream was also regarded as a measure of the fibers’ bonding ability in each pulp. The equation for predicted Bonding Indicator (BIN) was calculated by combining, through linear regression, the collapse resistance index and external fibrillation of the P16/R30 fractions for Pulps A and B. Predicted Bonding Indicator was found to correlate well with measured tensile strength. The BIN-equation was then applied also to the data for Pulps C-E, P16/R30, and Pulp A-E, P30/R50, and predicted Bonding Indicator showed good correlations with tensile strength also for these fibers. From the fiber raw data measured by the FiberLabTM instrument, the BIN-equation was used for each individual fiber. This made it possible to calculate a BIN-distribution of the fibers, that is, a distribution of fiber bonding ability. The thesis also shows how the BIN-distributions of fibers can be derived from FiberLabTM measurements of the entire pulp without mechanically separating the fibers by length first, for example in a Bauer McNett classifier. This is of great importance, as the method is intended for industrial use, and possibly as an online-method. Hopefully, the BIN-method will become a useful tool for process evaluations and optimizations in the future.
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| 3. |
- Christenson, Nina, 1975-
(författare)
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Knowledge, Value and Personal experience : Upper secondary students' resources of supporting reasons when arguing socioscientific issues
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on upper secondary students’ use of resources in their supporting reasons when arguing socioscientific issues (SSIs). The skills of argumentation have been emphasized in science education during the past decades and SSIs are proven a good context for learners to enhance skills of argumentation and achieve the goal of scientific literacy. Research has shown that supporting reasons from various resources are embedded in students’ argumentation on SSIs, and also that multi-perspective involvement in reasoning is important for the quality of argumentation. To explore the reasons used by students in arguing about SSIs in this thesis, the SEE-SEP model was adopted as an analytical framework. The SEE-SEP model covers the six subject areas of sociology/culture, economy, environment/ecology, science, ethics/morality and policy, which are connected to the three aspects of knowledge, value and personal experience. Two studies covering four SSIs (global warming, GMO, nuclear power and consumption) explore how students construct arguments on one SSI topic chosen by them. In paper I, I investigated students’ use of resources in their informal argumentation and to what extent students made use of knowledge. The results showed that students used value to a larger extent (67%) than knowledge (27%). I also found that the distribution of supporting reasons generated by students varied from the different SSIs. In paper II, I explored students’ use of resources in relation to students’ study background (science majors and social-science majors) and gender. The results showed that social-science majors and females generated more numbers of reasons and also showed a larger amount of multi-disciplinary resources in their supporting reasons. From the findings of this thesis, the SEE-SEP model was established as a suitable model used to analyze students’ resources of supporting reasons while arguing about SSIs. Furthermore, the potential for applying the SEE-SEP model in teachers’ SSI-teaching and students’ SSI-learning is suggested. The implications to research and teaching are also discussed.
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| 4. |
- Borg, Carola, 1973-
(författare)
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Utbildning för hållbar utveckling ur ett lärarperspektiv : Ämnesbundna skillnader i gymnasieskolan
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis investigates how teachers from different disciplines understand and implement education for sustainable development in their teaching. A nationwide questionnaire study was conducted with 3229 upper secondary school teachers representing 224 schools in Sweden. The concept of sustainable development is complex and research has shown that teachers exhibit uncertainties in their understanding of it, and that the way they conceptualize sustainable development can have consequences for how they incorporate it into their teaching. Previous research has emphasized that Education for Sustainable Development (ESD) should promote interdisciplinary and holistic learning rather than traditional subject-based learning. This is in accordance with the Swedish curriculum, which emphasizes that all teachers in all subjects should integrate education for sustainable development. The teachers in the study were grouped into four disciplines; science-, social science-, language-, and vocational/esthetical-practical teachers. The results showed that there were many subject-bound barriers to successful implementation of ESD. Teachers were influenced by their subject tradition in: 1) how they understand sustainable development, 2) which teaching methods they use, 3) which barriers they experience, and 4) which teaching tradition they work within. Because of these differences it is important to adjust any further training of teachers according to their discipline. This study highlights the need for improved teacher education and further training of in-service teachers; more than 70% of the teachers stated that they need such training. It also highlights the issue how strong subject-bound traditions make it difficult to implement general goals of the curricula such as sustainable development.
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| 5. |
- Joelsson, Tove, et al.
(författare)
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High strength paper from high yield pulps by means of hot-pressing
- 2020
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Ingår i: Nordic Pulp & Paper Research Journal. - : De Gruyter Open Ltd. - 0283-2631 .- 2000-0669. ; 35:2, s. 195-204
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Tidskriftsartikel (refereegranskat)abstract
- The hypothesis is that it should be possible to modify papermaking conditions in line with the softening properties of high yield pulp fibres and achieve similar strength properties to conventional chemical pulp based paper. We therefore investigated the rheological and physical properties of high yield pulp based papers during hot-pressing. Our results confirm that increased temperature combined with sufficient pressure enables permanent densification by softening of lignin, producing very high tensile strength. This treatment also significantly improved the wet tensile strength in comparison to bleached kraft pulp without using wet strength agents. The high yield pulps used here were spruce based thermomechanical pulp, chemi-thermomechanical pulp, and high temperature chemi-thermomechanical pulp, and birch-aspen based neutral sulphite semi chemical pulp, with spruce-pine based bleached kraft pulp as reference. Rapid Köhten sheets of 150 g/m 2 150\hspace{0.1667em}\text{g}/{\text{m}^{2}} and 50 % dryness were hot-pressed in a cylinder-press at 20-200 °C, 7 MPa, and 1 m/min. The mechanical properties showed great improvements in these high yield pulp papers, with tensile index increased to 75 kNm/kg and compression strength index to 45 kNm/kg; levels close to and better than bleached kraft. Wet strength increased to 16 Nm/g compared to 5 Nm/g for bleached kraft.
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| 6. |
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| 7. |
- Joelsson, Tove, et al.
(författare)
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Improving paper wet-strength by means hot-pressing and increased lignin content in pulp fibers
- 2019
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Ingår i: Paper Conference and Trade Show, PaperCon 2019. - : TAPPI Press. - 9781510893948 ; , s. 704-713
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Konferensbidrag (refereegranskat)abstract
- The research presented here show ways to improve wet strength by means of hot-pressing without strength additives when using lignin containing pulps as unbleached softwood chemical pulps (NSK) and lignin rich softwood chemithermomechanical pulps (CTMP). NSK (Northern Softwood kraft) laboratory scale produced pulps of 3 different levels of natural lignin (or kappa number) and two commercial pulps, NBSK (Northern Bleached Softwood kraft) and CTMP, were compared evaluating dry- and wet-strength properties. Staining methods and light microscope were used to study cross sections of paper sheets. The CTMP fibers collapse to an increasing degree with pressing temperature whereas NBSK/NSK do not change. The microscopy methods show the distribution of lignin within the paper structure. Sheets made from NSK show a significant increase in wet strength from 4kNm/kg to 23kNm/kg, when increasing temperature from 20°C to 200°C. CTMP show corresponding increase from 2kNm/kg to 16kNm/kg. No increase in dry strength or in density can be observed in case of NBSK/NSK, while the CTMP show an increase of 53% and 100% respectively. The SCT values show an increase up to 35% for lignin-rich NSK based paper sheets when hot-pressing.
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| 8. |
- Joelsson, Tove, et al.
(författare)
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Improving paper wet strength via increased lignin content and hot-pressing temperature
- 2020
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Ingår i: TAPPI Journal. - 0734-1415. ; 19:10, s. 487-499
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Tidskriftsartikel (refereegranskat)abstract
- It is known that the strength properties of wood-based paper materials can be enhanced via hot-pressing techniques. Today, there is a desire not only for a change from fossil-based packaging materials to new sustainable bio-based materials, but also for more effective and eco-friendly solutions for improving the dry and wet strength of paper and board. Against this background, hot pressing of paper made from high yield pulp (HYP), rich in lignin, becomes highly interesting. This study investigated the influence of pressing temperature and native lignin content on the properties of paper produced by means of hot pressing. Kraft pulps of varied lignin content (kappa numbers: 25, 50, 80) were produced at pilot scale from the same batch by varying the cooking time. We then studied the effect of lignin content by evaluating the physical properties of Rapid When sheets after hot pressing in the temperature range of 20 degrees C-200 degrees C with a constant nip pressure of 7 MPa. The pilot-scale cooked pulps were compared with reference samples of mill-produced northern bleached softwood kraft (NBSK) pulp and mill-produced chemithermomechanical pulp (CTMP). Generally, the results demonstrated that lignin content had a significant effect on both dry and wet tensile index. All of the pilot cooked pulps with increased lignin content had a higher tensile index than the reference NBSK pulp. To obtain high tensile index, both dry and wet, the pressing temperature should be set high, preferably at least 200 degrees C; that is, well above the glass transition temperature (Tg) for lignin. Moreover, the lignin content should preferably also be high. All kraft pulps investigated in this study showed a linear relationship between wet strength and lignin content.
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| 9. |
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| 10. |
- Pettersson, Gunilla, et al.
(författare)
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Aspects on bond strength in sheet structures from TMP and CTMP - a review
- 2021
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Ingår i: Nordic Pulp & Paper Research Journal. - : Walter de Gruyter GmbH. - 0283-2631 .- 2000-0669. ; 36:2, s. 177-213
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Forskningsöversikt (refereegranskat)abstract
- High yield pulps (HYP), manufactured in mechanical and chemimechanical pulping processes, are mainly used in graphic papers and paper grades where a high bulk is preferable, like in paperboards. Moreover, packaging papers with very high demands on both dry and wet strength could be manufactured from HYP in a near future. Preferred bonds between fibre components (long fibres, shortened fibres and fines) in the various paper grades are quite different. In the review, plausible effects of mechanical interlocking, intermolecular interactions ("physical bonding"), hydrogen bonds, intermixing of polymers, additives and possible specific interactions in the formation of strong bonds in sheet structures from HYP are discussed. A required condition for high bond strength in sheets from HYP furnishes is that fibre components are forced into sufficiently close contact. This is to a great extent impeded if the fibre walls are too stiff. Consequently, the current review focuses on both how fibre fractions should preferably be developed for different end uses and how suitable bonds might be achieved in different paper grades. The ideal type of bonds is certainly different depending on the demands on the final paper quality.
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