| 1. |
- Davidsson, Per, 1957-, et al.
(författare)
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The role of social and human capital among nascent entrepreneurs
- 2003
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Ingår i: Journal of Business Venturing. - : Elsevier. - 0883-9026 .- 1873-2003. ; 18:3, s. 301-331
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Tidskriftsartikel (refereegranskat)abstract
- This study examines nascent entrepreneurship by comparing individuals engaged in nascent activities (n=380) with a control group (n=608), after screening a sample from the general population (n=30,427). The study then follows the developmental process of nascent entrepreneurs for 18 months. Bridging and bonding social capital, consisting of both strong and weak ties, was a robust predictor for nascent entrepreneurs, as well as for advancing through the start-up process. With regard to outcomes like first sale or showing a profit, only one aspect of social capital, viz. being a member of a business network, had a statistically significant positive effect. The study supports human capital in predicting entry into nascent entrepreneurship, but only weakly for carrying the start-up process towards successful completion.
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| 2. |
- Delmar, Frédéric, et al.
(författare)
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Arriving at the high growth firm
- 2003
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Ingår i: Journal of Business Venturing. - 0883-9026 .- 1873-2003. ; 18:2, s. 189-216
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Tidskriftsartikel (refereegranskat)
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| 3. |
- Iwata, HP, et al.
(författare)
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Stacking faults in silicon carbide
- 2003
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Ingår i: Physica. B, Condensed matter. - : Elsevier. - 0921-4526 .- 1873-2135. ; 340, s. 165-170
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Tidskriftsartikel (refereegranskat)abstract
- We review of our theoretical work on various stacking faults in SiC polytypes. Since the discovery of the electronic degradation phenomenon in 4H-SiC p-i-n diodes, stacking faults in SiC have become a subject of intensive study around the globe. At the beginning of our research project, the aim was to find the culprit for the degradation phenomenon, but in the course of this work we uncovered a wealth of information for the general properties of stacking faults in SiC. An intuitive perspective to the diverse nature of stacking faults in SiC will be given in this conference report. (C) 2003 Published by Elsevier B.V.
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| 4. |
- Blumenau, A.T., et al.
(författare)
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Basal plane partial dislocations in silicon carbide
- 2003
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Ingår i: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 340, s. 160-164
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Tidskriftsartikel (refereegranskat)abstract
- Under operating conditions (forward bias) bipolar 4H- and 6H-SiC devices are known to degrade rapidly through stacking fault formation and expansion in the basal plane. It has been suggested that a recombination-enhanced dislocation glide (REDG) mechanism allows the bordering Shockley partial dislocations to overcome their barrier to glide motion and thus results in the observed stacking fault growth. In this work, we investigate the structure and properties of the participating Shockley partials by means of density functional-based atomistic calculations. Their glide motion is modelled in a process involving the formation and subsequent migration of kinks. This in combination with an analysis of the electronic structure of the partials allows an identification of those types which will be affected by the REDG mechanism.
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| 5. |
- Coutinho, J., et al.
(författare)
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The formation, dissociation and electrical activity of divacancy-oxygen complexes in Si
- 2003
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Ingår i: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 340, s. 523-527
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Tidskriftsartikel (refereegranskat)abstract
- Density functional calculations are carried out on divacancy-oxygen (V2O and V2O2) complexes in silicon, paying particular attention to their formation and dissociation mechanisms as well as their electrical activity. The formation of V2O around 220°C is controlled by the diffusion of V2 to immobile oxygen traps, while it dissociates around 300°C into VO and V. V2O and V2O2 are found to possess deep single and double acceptor levels as well as deep donor levels similar to those of V2.
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| 6. |
- Hourahine, B., et al.
(författare)
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Platinum and gold dihydrides in silicon
- 2003
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Ingår i: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 340, s. 668-72
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Tidskriftsartikel (refereegranskat)abstract
- The structural, electronic and vibrational properties of single substitutional platinum or gold atoms complexed with two hydrogen atoms in silicon are considered on the basis of local density functional theory. The calculated behaviour of these centres is compared with experimental results from infrared absorption and deep-level transient spectroscopy. In contrast with suggestions in the literature, based on hyperfine parameters of electron-paramagnetic resonance, we suggest that such complexes possess direct metal-H bonding.
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| 7. |
- Ji, Xiaoyan, et al.
(författare)
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Saturated thermodynamic properties for the air-water system at elevated temperature and pressure
- 2003
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Ingår i: Chemical Engineering Science. - : Elsevier BV. - 0009-2509 .- 1873-4405. ; 58, s. 5069-5077
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Tidskriftsartikel (refereegranskat)abstract
- A new thermodynamic model is proposed to calculate the thermodynamic properties for the air-water system in which the dry air was assumed to be a mixture of nitrogen and oxygen with the mole fractions of 0.7812 and 0.2188, respectively. For the vapor phase, fugacity coefficients were calculated with the modified Redlich-Kwong equation of state in which a new interaction parameter of oxygen and water was correlated from the experimental data of oxygen-water system. The dissolved gas followed Henry's law. Henry's constant of nitrogen was calculated with the Helgeson equation of state and that for oxygen was correlated from the experimental data of oxygen-water system. The proposed model was verified by comparing the calculated results with the available experimental data. It is shown that the proposed model is suitable for predicting saturated thermodynamic properties for the air-water system up to 300°C and 200 atm. Furthermore, the prediction results of the proposed model are better than those calculated with the model of Rabinovich and Beketov (Moist Gases, Thermodynamic Properties. Begell: House, 1995), and the application range is wider than that of the model of Hyland and Wexler (ASHRAE Trans. 89(2A) (1983a, b) 500-519, 520-535) which are among the best of today's models
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| 8. |
- Markevich, V.P., et al.
(författare)
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Electronic properties of vacancy-oxygen complexes in SiGe alloys
- 2003
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Ingår i: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 340, s. 790-4
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Tidskriftsartikel (refereegranskat)abstract
- Capacitance transient techniques, combined with ab initio modeling, were employed to study the electronic properties and structure of vacancy-oxygen (VO) complexes in unstrained Czochralski-grown Si1-xGex crystals (0
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| 9. |
- Naydenov, Valeri, et al.
(författare)
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Vanadium modified AlPO-5 spheres through resin macrotemplating
- 2003
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Ingår i: Microporous and Mesoporous Materials. - : Elsevier BV. - 1387-1811 .- 1873-3093. ; 66:2-3, s. 321-329
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Tidskriftsartikel (refereegranskat)abstract
- Vanadium modified AlPO-5 spheres were prepared using a cation exchange resin as a macrotemplate. Initially, a AlPO-5–resin composite was obtained by a hydrothermal treatment of preformed Al–resin composites with a mixture of phosphoric acid, tetraethyl ammonium hydroxide and distilled water. Vanadium was introduced in a subsequent step into the AlPO-5–resin composite by a secondary ion exchange reaction. The final self-bonded vanadium modified AlPO-5 spheres were obtained by combustion of the organic ion exchanger. Product particles were characterized by SEM, XRD, AAS, nitrogen adsorption measurements, Raman and UV–vis diffusion reflectance spectroscopy. Materials with controlled macroshape and porosity were prepared by the approach. Further, control of amounts of vanadium present within the AlPO-5 spheres was achieved by varying the concentration of the vanadium solution used for ion exchange. The nature of the vanadium species present was dependent on the metal loading. Isolated and highly dispersed vanadium in tetrahedral coordination was present at low loadings, whereas polymeric and/or V2O5 crystallites were observed at higher loadings.
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| 10. |
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