| 1. |
- Adams, Robin, et al.
(författare)
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What is the word for 'Engineering' in Swedish : Swedish students conceptions of their discipline
- 2007
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Engineering education in Sweden – as in the rest of the world – is experiencing a decline in student interest. There are concerns about the ways in which students think about engineering education, why they join an academic programme in engineering, and why they persist in their studies. In this context the aims of the Nationellt ämnesdidaktiskt Centrum för Teknikutbildning i Studenternas Sammanhang project (CeTUSS) is to investigate the student experience and to identify and support a continuing network of interested researchers, as well as in building capacity for disciplinary pedagogic investigation. The Stepping Stones project brings together these interests in a multi-researcher, multi-institutional study that investigates how tudents and academic staff perceive engineering in Sweden and in Swedish education. The first results of that project are reported here. As this study is situated uniquely in Swedish education, it allows for exploration of “a Swedish perspective” on conceptions of engineering. The Stepping Stones project was based on a model of research capacity-building previously instantiated in the USA and Australia (Fincher & Tenenberg, 2006).
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| 2. |
- Lindberg, Vanja
(författare)
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First principles study of CO reactivity on metallic nano particles
- 2007
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Konferensbidrag (refereegranskat)abstract
- The activity of a surface is determined by the local electronic structure. When nano particles are adsorbed, the catalytic properties will change. Surfaces with adsorbed nano particles often show a significantly higher chemical reactivity than the clean counterpart. Gold, for instance, shows an extra high activity towards many reactions, such as low-temperature catalytic combustion, partial oxidation of hydrocarbons and CO oxidation when dispersed as ultra-fine particles on metal oxide surfaces. In the case of CO oxidation, the activity has been observed to depend critically on the nano particle size, the nature of the support and the detailed synthetic procedure. Since it has been observed experimentally that the chemical reactivity of a nanoparticulated surface tend to depend on the size of the adatom structures, suggesting a quantum size effect, we find it well motivated to perform a theoretical investigation with focus on the cluster-size dependence. We have chosen to model CO interaction with sodium nano particles with focus on small particles, containing only a few atoms, since we expect the eventual quantum effects to be most pronounced for these. Further, we limit our investigation to unsupported nano particles because our previous investigations [1] have shown that it is predominately states localized to the nano particle region that contribute to the local electronic structure above the particle itself. The calculations have been performed in the context of density functional theory applying the MIKA real-space program package [2], using norm-conserving pseudo-potentials for the molecule. The nano particle has been modeled as a cylindrically symmetric quantum dot. For further details, see [3,4]. Our results show that the charge transfer between the nano particle and the CO molecule depends critically on the nano particle size, and that this dependence is intimately connected to the local electronic structure at the point where the molecule approaches the particle. The key factor for charge transfer turns out to be the presence of states with the symmetry of the chemically active molecular orbital at the Fermi level. [1] T. Torsti, V. Lindberg, M. J. Puska ,and B. Hellsing, Phys. Rev. B 66, 235420 (2002). [2] M. Heiskanen, T. Torsti, M. J. Puska, and R. M. Nieminen, Phys. Rev. B 63, 245106 (2001). [3] V. Lindberg and B. Hellsing, J. Phys. Condens. Matter 17, S1075 (2005). [4] V. Lindberg, T. Petersson, and B. Hellsing, Surf. Sci. 600, 6 (2006).
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| 3. |
- Lindberg, Vanja, et al.
(författare)
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Metallic quantum dots
- 2005
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Ingår i: J. Phys: Condens. Matter. ; 17
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Tidskriftsartikel (refereegranskat)
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| 4. |
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| 5. |
- Lindberg, Vanja, et al.
(författare)
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Quantum size effects of CO reactivity on metallic quantum dots
- 2006
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Ingår i: Surface Science. - : Elsevier B.V.. - 0039-6028 .- 1879-2758. ; 600:1, s. 6-14
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Tidskriftsartikel (refereegranskat)abstract
- We study the reactivity of a metallic quantum dot when exposed to a gas phase CO molecule. First, we perform a Newns–Anderson model calculation in which the valence electrons of the quantum dot are confined by a finite potential well and the molecule is characterized by its lowest unoccupied molecular orbital in the gas phase. A pronounced quantum size effect regarding the charge transfer between the quantum dot and molecule is observed. We then perform a first-principles calculation for a selected size interval. The quantum dot is described within the jellium model and the molecule by pseudopotentials. Our results show that the charge transfer between the quantum dot and the molecule depends critically on the size of the quantum dot, and that this dependence is intimately connected with the electronic structure. The key factor for charge transfer is the presence of states with the symmetry of the chemically active molecular orbital at the Fermi level.
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| 6. |
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| 7. |
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| 8. |
- Vingård, Eva, et al.
(författare)
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A physical fitness programme during paid working hours - impact on health and work ability among women working in the social service sector : a three year follow up study
- 2009
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Ingår i: Work. - 1051-9815 .- 1875-9270. ; 34:3, s. 339-344
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Tidskriftsartikel (refereegranskat)abstract
- In order to study the influence of a physical fitness programme on work ability among women employed in the social sector an intervention was offered to 205 women working in the social care sector in a municipality in Sweden. The reference group comprised 165 women from the same sector working in another municipality. All participants were employed and answered questionnaires at baseline and after 36 months. For women younger than 45 years, work ability and general health improved significantly while for women, 45 years or older, future work expectations improved. For women with less musculoskeletal pain, improvements were observed regarding future work expectations, as well as work ability and general health while for women with more musculoskeletal pain, improvements were observed for general health and future work expectations. Well-structured physical fitness programmes at the worksite can be useful in contributing to individual's experiences of improvements in their own capacity as well as increased health and wellbeing.
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