| 1. |
- Sugita, S., et al.
(författare)
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The geomorphology, color, and thermal properties of Ryugu: Implications for parent-body processes
- 2019
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Ingår i: Science. - : AAAS. - 0036-8075 .- 1095-9203. ; 364:6437
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Tidskriftsartikel (refereegranskat)abstract
- Asteroids fall to Earth in the form of meteorites, but these provide little information about their origins. The Japanese mission Hayabusa2 is designed to collect samples directly from the surface of an asteroid and return them to Earth for laboratory analysis. Three papers in this issue describe the Hayabusa2 team's study of the near-Earth carbonaceous asteroid 162173 Ryugu, at which the spacecraft arrived in June 2018 (see the Perspective by Wurm). Watanabeet al.measured the asteroid's mass, shape, and density, showing that it is a “rubble pile” of loose rocks, formed into a spinning-top shape during a prior period of rapid spin. They also identified suitable landing sites for sample collection. Kitazatoet al.used near-infrared spectroscopy to find ubiquitous hydrated minerals on the surface and compared Ryugu with known types of carbonaceous meteorite. Sugitaet al.describe Ryugu's geological features and surface colors and combined results from all three papers to constrain the asteroid's formation process. Ryugu probably formed by reaccumulation of rubble ejected by impact from a larger asteroid. These results provide necessary context to understand the samples collected by Hayabusa2, which are expected to arrive on Earth in December 2020.Science, this issue p.268, p.272, p.eaaw0422; see also p.230
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| 2. |
- Solmi, M, et al.
(författare)
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- 2022
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Ingår i: Journal of affective disorders. - : Elsevier BV. - 1573-2517 .- 0165-0327. ; 299, s. 367-376
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Tidskriftsartikel (refereegranskat)
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| 3. |
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| 4. |
- Yamada, Y., et al.
(författare)
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Dehydrogenation process of Mg-Ni based switchable mirrors analyzed by in situ spectroscopic ellipsometry
- 2012
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Ingår i: Solar Energy Materials and Solar Cells. - : Elsevier BV. - 0927-0248 .- 1879-3398. ; 99:SI, s. 84-87
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Tidskriftsartikel (refereegranskat)abstract
- The dehydrogenation process of hydrogenated switchable mirrors using magnesium-nickel alloy thin film was studied in situ using spectroscopic ellipsometry. Ellipsometric angles Psi and Delta of the switchable mirrors varied drastically as a result of dehydrogenation, which is a transformation from transparent to reflective states. The process was analyzed by dividing into the following three phases. The first phase was the dehydrogenation process of a thin Mg4Ni layer with several nanometers at a hydrogenated Pcl/Mg4Ni interface. The second phase was the dehydrogenation processes of the hydrogenated Mg4Ni layer, which proceeded from the Pd/Mg4Ni interface to the substrate. The final phase was the desorption process of hydrogen, which was absorbed in Mg4Ni as solid solution and the dehydrogenation process was terminated.
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| 5. |
- Yamada, Y., et al.
(författare)
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Estimation of the amount of the proton injected into tungsten oxide thin films during deposition using spectroscopic ellipsometry
- 2007
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Ingår i: Thin Solid Films. - : Elsevier BV. - 0040-6090 .- 1879-2731. ; 515:7-8, s. 3825-3829
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Tidskriftsartikel (refereegranskat)abstract
- Tungsten oxide thin films injected with protons (HxWO3) during deposition were prepared on glass substrates using reactive direct-current magnetron sputtering in a mixture of argon, oxygen, and hydrogen gases. The as-deposited films were bronze. The amount of injected protons, namely the x-value in HxWO3, was estimated using the dispersion of the extinction coefficient (κ). The dispersion was evaluated by analyzing the experimental spectra measured with spectroscopic ellipsometry and optical photometry using the model composed of a homogeneous tungsten bronze layer with an additional surface roughness layer. As a result of analysis, the x-value was estimated to be approximately 0.1.
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| 6. |
- Yamada, Y, et al.
(författare)
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In situ spectroscopic ellipsometry study of the hydrogenation process of switchable mirrors based on magnesium-nickel alloy thin films
- 2010
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 107:4, s. 043517-
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Tidskriftsartikel (refereegranskat)abstract
- The hydrogenation process of switchable mirrors using magnesium-nickel alloy thin films including a thin palladium cap layer was analyzed by measuring the variation in ellipsometric angles Psi and Delta using in situ spectroscopic ellipsometry. The process was divided into three phases and each phase was identified as follows. The first phase was the process in which the solid solution was formed because a Mg-Ni alloy in its metal state absorbs hydrogen. The second phase was the hydrogenation processes of the solid solution and the metal Pd layers. The third phase was the hydrogenation process of residual metal Pd in the Pd layer. In the initial state of the second phase, a hydride of the alloy was nucleated at the film/substrate interface as a result of hydrogenation of the solid solution, and a mixture layer of the hydride and solution was formed. With proceeding hydrogenation, the thickness of the mixture layer increased and the homogenous hydride layer was afterwards formed at the film/substrate interface. As a result of further hydrogenation, the Mg-Ni alloy layer was completely hydrogenated. After the alloy layer was completely hydrogenated, the hydrogenation of Pd was terminated.
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