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| 2. |
- Naumovska, Elena, et al.
(författare)
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Local structure of hydrated nanocrystalline films of the proton conductor BaZr 1-x Sc x O 3-x/2 studied by infrared spectroscopy
- 2024
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Ingår i: Vibrational Spectroscopy. - 0924-2031. ; 130
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Tidskriftsartikel (refereegranskat)abstract
- We report results from a study of the local structure of hydrated nanocrystalline 2 μm films of the well known proton conductor BaZr1-xScxO3-x/2 with x = 0.45, 0.54 and 0.64, using infrared (IR) spectroscopy. The films were prepared by magnetron sputtering. Analysis of the IR spectra focused on the O–H stretching region (2000—3700 cm-1), which reveals the presence of several distinct O–H stretching bands for which the intensity and frequency of each band vary in an unsystematic manner with Sc concentration. The spectra for the two higher Sc concentrations, x = 0.54 and 0.64, exhibit a distinct, highly intense O–H stretching band centered at around 3400–3500 cm-1, which is assigned to relatively symmetric, weakly hydrogen-bonding, proton configurations. The spectrum for the lower Sc concentration, x = 0.45, does not feature such a band but a broader, weaker, O–H stretching band between approximately 2500 and 3700 cm-1, suggesting that the protons are more homogeneously distributed over a range of different local proton coordinations in this relatively weakly doped material. A comparison to the IR spectra of powder samples of similar compositions suggests that for x = 0.45, the spectra and proton coordination of films and powder samples are similar, whereas for x = 0.54 and 0.64, a larger fraction of protons seems to be located in weakly hydrogen-bonding proton configurations in the films compared to the respective powder samples.
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| 3. |
- Nzulu, Gabriel Kofi, 1974-, et al.
(författare)
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Growth and thermal stability of Sc-doped BaZrO 3 thin films deposited on single crystal substrates
- 2023
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Ingår i: Thin Solid Films. - : Elsevier BV. - 0040-6090 .- 1879-2731. ; 772
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Tidskriftsartikel (refereegranskat)abstract
- Thin films of BaZr1-xScxO3-x/2, (0 ≤ x ≤ 0.64), well known as proton conducting solid electrolytes for intermediate temperature solid oxide fuel cell, were deposited by magnetron sputtering. X-ray diffraction analysis of the as deposited films reveals the presence of single-phase perovskite structure. The films were deposited on four different substrates (c-Al2O3, LaAlO3〈100〉, LaAlO3〈110〉, LaAlO3〈111〉) yielding random, (110)- or (100)-oriented films. The stability of the as-deposited films was assessed by annealing in air at 600 °C for 2 h. The annealing treatment revealed instabilities of the perovskite structure for the (110) and randomly oriented films, but not for (100) oriented film. The instability of the coating under heat treatment was attributed to the low oxygen content in the film (understoichiometry) prior annealing combined with the surface energy and atomic layers stacking along the growth direction. An understoichiometric (100) oriented perovskite films showed higher stability of the structure under an annealing in air at 600 °C.
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| 4. |
- Rhodin, Martin, et al.
(författare)
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A Method for Model Based Automotive Software Development
- 2002
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Ingår i: Proc. Work in Progress and Industrial Experience Sessions of the 12th Euromicro Conference on Real-Time Systems.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The distributed electrical system in the latest Volvo models, S80 and New V70, put new demands on software development methods. Increased demands for higher flexibility in the physical system requires higher flexibility in distributing functionality and more complex functionality requires higher quality ofrequirement specifications.In the MESC method for model based automotive software development, function development is separated from the system development, which helps parallel work and improves reusability.An object oriented function model provides means to analyse and describe functionality in a structured way and serves as an input to the development of a design model which can be validated against functional requirements.In the system design phase, logical objects from the model are allocated on the physical system architecture.
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