| 1. |
- Lindbad, Rebecka, et al.
(författare)
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Electronic Structure of TiO2/CH(3)NH(3)Pbl(3) Perovskite Solar Cell Interfaces
- 2014
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Ingår i: Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185 .- 1948-7185. ; 5:4, s. 648-653
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Tidskriftsartikel (refereegranskat)abstract
- The electronic structure and chemical composition of efficient CH(3)NH(3)Pbl(3) perovskite solar cell materials deposited onto mesoporous TiO2 were studied using photoelectron spectroscopy with hard X-rays. With this technique, it is possible to directly measure the occupied energy levels of the perovskite as well as the TiO2 buried beneath and thereby determine the energy level matching of the interface. The measurements of the valence levels were in good agreement with simulated density of states, and the investigation gives information on the character of the valence levels. We also show that two different deposition techniques give results indicating similar electronic structures.
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| 2. |
- Lindblad, Rebecka, et al.
(författare)
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Electronic Structure of TiO2/CH3NH3PbI3 Perovskite Solar Cell Interfaces
- 2014
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Ingår i: Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185 .- 1948-7185. ; 5:4, s. 648-653
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Tidskriftsartikel (refereegranskat)abstract
- The electronic structure and chemical composition of efficient CH3NH3PbI3 perovskite solar cell materials deposited onto mesoporous TiO2 were studied using photoelectron spectroscopy with hard X-rays. With this technique, it is possible to directly measure the occupied energy levels of the perovskite as well as the TiO2 buried beneath and thereby determine the energy level matching of the interface. The measurements of the valence levels were in good agreement with simulated density of states, and the investigation gives information on the character of the valence levels. We also show that two different deposition techniques give results indicating similar electronic structures.
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| 3. |
- Lindvall, Johannes, 1975, et al.
(författare)
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Party choice in hard times: Group-specific responses to economic downturns in Sweden
- 2013
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Ingår i: Electoral Studies. - : Elsevier BV. - 0261-3794 .- 1873-6890. ; 32:3, s. 529-535
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Tidskriftsartikel (refereegranskat)abstract
- This article asks if, when, and why different groups of voters behave differently in the wake of economic downturns. We examine two Swedish elections (1994 and 2010) that were held just after two deep recessions (the financial crisis of 1991-1993 and the 2008-2009 Great Recession). We find that group differences were much larger in 2010 than they were in 1994. After the 1991-1993 recession, the government's electoral support declined across the board. In 2010, there were large differences between voters with low economic status (who were unlikely to support the government) and voters with high economic status (who were likely to do so). Our findings suggest that group differences in electoral behavior after an economic downturn depend on contextual differences across elections. We argue that future research should pay close attention to the magnitude of economic shocks, the development of asset prices (especially real estate), and changes in social policy. (C) 2013 Elsevier Ltd. All rights reserved.
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| 4. |
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| 5. |
- Magnusson, Johan, et al.
(författare)
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All Aboard: ERP Implementation as Participatory Design
- 2011
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Ingår i: Americas Conference on Information Systems.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Following a previous description of Enterprise Resource Planning (ERP) implementations as participatory design (Pries-Heje & Dittrich, 2009), this paper explores the case of a medium-sized, family-owned manufacturing company and its endeavors with changing their current ERP system. The case was selected on the premise of it being perceived a success by the involved stakeholders. Through a series of interviews and analysis of secondary material, the case covers the period between 1995 and 2010. As the results show, several instances of user involvement and participation can be found throughout the case. According to the respondents, this is seen as one of the central elements of the success. This is discussed in relation to previous findings and a call for future research into ERP implementation is presented.
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| 6. |
- Pazoki, Meysam, et al.
(författare)
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Mesoporous TiO2 microbead electrodes for solid state dye-sensitized solar cells
- 2014
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Ingår i: RSC Advances. - : Royal Society of Chemistry (RSC). - 2046-2069. ; 4:91, s. 50295-50300
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Tidskriftsartikel (refereegranskat)abstract
- Mesoporous TiO2 microbead films have been investigated as working electrodes for solid state dye sensitized solar cells and 3.5% efficiency was achieved for 4 micrometer thick films under 1 sun illumination. Compared to conventional mesoporous solar cells, microbead films have higher porosity, increased open circuit voltage, lower fill factor and current density, faster transport time and lower electron lifetime. Cross sectional scanning electron microscopy results show that the pore filling of a solid hole conductor (spiro-OMeTAD) inside the entire mesoporous bead film is very good even for 4 micrometer thick films. The high porosity of the microbead film allows good penetration of spiro in thick films, while its high surface area ensures good dye coverage. X-ray photoelectron spectroscopy data reveals a lower density of intra-bandgap trap states for microbead films compared to conventional mesoporous TiO2 films, which could be in part responsible for faster transport of electrons and higher voltage in microbead films. Optimization of microbead films for solid state dye sensitized solar cells can be an interesting possibility for highly efficient and relatively thick film solid state solar cells.
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| 7. |
- Serrano, Erik, 1968-, et al.
(författare)
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Wet glued laminated beams using side boards of Norway spruce
- 2011
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In a previous research project, carried out during the years 2006-2008, the possibility to manufacture wet glued laminated beams using ungraded laminations of Norway spruce side boards was investigated with very promising results.In the project presented in this report, the performance of the wet glued beams has been further investigated and developed as regards grading of side board laminations, bond line properties and lamination finger jointing. The possibility to use scanning equipment for measurement of fibre angles and prediction of strength and stiffness of boards and beams has been studied and the procedures for technical approval and CE marking have been probed into. Studies concerning market and economy for the beams and layouts for a pilot plant and a full capacity plant, respectively, for production of such beams have also been carried out.The possibility to grade side boards in the wet state using axial dynamic excitation was investigated with a positive result. From such excitation, a board’s stiffness (modulus of elasticity) could be determined. Accordingly, grading criteria regarding axial stiffness, and knot size, was applied to grade side board laminations into two classes; outer and inner laminations. Strength and stiffness tests of beams manufactured from such graded laminations showed that the beams actually could challenge first rate glulam and LVL products available on the market.Regarding beam shape and shape stability, cross section cupping may need further attention. Even if this deformation was small, it was still visible to the naked eye. The problem could probably be overcome if the beams are dried to a moisture content of 12-14% before planing.Results of shear tests show that green glued bond lines can fulfil strength requirements for glulam. However, delamination requirements for service class 3 (outdoors) were not fully met. From small scale tensile testing of glued bonds it was concluded that green glued bonds with high density wood have the same tensile strength and fracture energy as dry glued bonds. For bonds with low density wood and/or small amount of adhesive, the tensile strength could be lower than for dry glued bonds, whereas the fracture energy was on a similar level.Strength testing of wet and dry glued finger joints demonstrated that joints glued from high density wood was significantly stronger than low density joints and that there was no significant difference between the strength of green glued joints and joints glued after drying. From X-ray measurement it was shown that the glue penetration into the wood fibres is much deeper in a green glued joint than in a joint that is glued in the dried state.From scanning algorithms developed within the scope of this project it is possible to obtain reasonably accurate predictions of grain-angle distributions on board surfaces as well as rather accurate descriptions of knot locations and of fibre-angle disturbances around knots. From scanning of board ends, cross section characteristics with respect to radial and tangential directions and of annual ring widths could also be determined. Finally, both board and beam stiffness were predicted from this data, with an accuracy that is comparable with the one obtained from well-reputed commercial grading systems.
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| 8. |
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| 9. |
- Tian, Haining, et al.
(författare)
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Enhancement of p-Type Dye-Sensitized Solar Cell Performance by Supramolecular Assembly of Electron Donor and Acceptor
- 2014
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 4, s. 4282-
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Tidskriftsartikel (refereegranskat)abstract
- Supramolecular interactions based on porphyrin and fullerene derivatives were successfully adopted to improve the photovoltaic performance of p-type dye-sensitized solar cells (DSCs). Photoelectron spectroscopy (PES) measurements suggest a change in binding configuration of ZnTCPP after co-sensitization with C60PPy, which could be ascribed to supramolecular interaction between ZnTCPP and C60PPy. The performance of the ZnTCPP/C60PPy-based p-type DSC has been increased by a factor of 4 in comparison with the DSC with the ZnTCPP alone. At 560 nm, the IPCE value of DSCs based on ZnTCPP/C60PPy was a factor of 10 greater than that generated by ZnTCPP-based DSCs. The influence of different electrolytes on charge extraction and electron lifetime was investigated and showed that the enhanced V-oc from the Co2+/(3+)(dtbp)(3)-based device is due to the positive E-F shift of NiO.
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| 10. |
- Walser, Marion, 1961, et al.
(författare)
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Different modes of GH administration influence gene expression in the male rat brain
- 2014
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Ingår i: Journal of Endocrinology. - 0022-0795 .- 1479-6805. ; 222:2, s. 181-190
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Tidskriftsartikel (refereegranskat)abstract
- The endogenous secretion pattern in males of GH is episodic in rats and in humans, whereas GH administration is usually even. Different types of GH administration have different effects on body mass, longitudinal bone growth, and liver metabolism in rodents, whereas possible effects on brain plasticity have not been investigated. In this study, GH was administered as a continuous infusion or as two daily injections in hypophysectomized male rats. Thirteen transcripts previously known to respond to GH in the hippocampus and parietal cortex (cortex) were assessed by RT-PCR. To investigate the effects of type of GH administration on several transcripts with different variations, and categories of transcripts (neuron-, glia-, and GH-related), a mixed model analysis was applied. Accordingly, GH injections increased overall transcript abundance more than GH infusions (21% in the hippocampus, P<0.001 and 10% in the cortex, PZ0.09). Specifically, GH infusions and injections robustly increased neuronal hemoglobin beta (Hbb) expression significantly (1.8- to 3.6-fold), and GH injections were more effective than GH infusions in increasing Hbb in the cortex (41%, PZ0.02), whereas a 23% difference in the hippocampus was not significant. Also cortical connexin 43 was higher in the group with GH injections than in those with GH infusions (26%, P<0.007). Also, there were differences between GH injections and infusions in GH-related transcripts of the cortex (23%, PZ0.04) and glia-related transcripts of the hippocampus (15%, PZ0.02). Thus, with the exception of Hbb there is a moderate difference in responsiveness to different modes of GH administration. © 2014 Society for Endocrinology.
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