Knowledge of the average density of the crust of a planet is important in determining its interior structure. The combination of high-resolution gravity and topography data has yielded a low density for the Moon's crust, yet for other terrestrial planets the resolution of the gravity field models has hampered reasonable estimates. By using well-chosen constraints derived from topography during gravity field model determination using satellite tracking data, we show that we can robustly and independently determine the average bulk crustal density directly from the tracking data, using the admittance between topography and imperfect gravity. We find a low average bulk crustal density for Mars, 2582 ± 209 kg m. This bulk crustal density is lower than that assumed until now. Densities for volcanic complexes are higher, consistent with earlier estimates, implying large lateral variations in crustal density. In addition, we find indications that the crustal density increases with depth.
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http://dx.doi.org/10.1002/2017GL074172 | DOI Listing |
Rev Neurosci
January 2025
Department of Histology and Embryology, School of Basic Medicine, Hengyang Medical School, 34706 University of South China, Hengyang 421001, China.
Depression is a common mental disorder characterized by a high prevalence and significant adverse effects, making the searching for effective interventions an urgent priority. In recent years, physical activity (PA) has increasingly been recognized as a standard adjunctive treatment for mental disorders owing to its low cost, easy application, and high efficiency. Epidemiological data shows positive preventive and therapeutic effects of PA on mental illnesses such as depression.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
MOE Key Laboratory for UV Light-Emitting Materials and Technology, Department of Physics, Northeast Normal University, Changchun, Jilin 130024, PR China; Faculty of Chemistry, Northeast Normal University, Changchun, Jilin 130024, PR China. Electronic address:
Considering factors such as crustal reserves, atomic mass, redox potential and energy density, sodium-ion batteries (SIBs) are regarded as the most promising alternative to lithium-ion batteries (LIBs). Transition metal-based layered oxides, especially typical NaMnO, stand out among cathode materials due to their low cost and high energy density. However, NaMnO cathodes face several challenges, including Jahn-Teller distortion, manganese dissolution, structural collapse, irreversible phase transition and significant capacity loss.
View Article and Find Full Text PDFNat Commun
January 2025
Department of Earth Science, University of Bergen, Bergen, Norway.
Plate tectonics predicts that mountain ranges form by tectono-magmatic processes at plate boundaries, but high topography is often observed along passive margins far from any plate boundary. The high topography of the Scandes range at the Atlantic coast of Fennoscandia is traditionally assumed isostatically supported by variation in crustal density and thickness. Here we demonstrate, by our Silverroad seismic profile, that the constantly ~44 km thick crust instead is homogenous above the Moho, and Pn-velocity abruptly change from 7.
View Article and Find Full Text PDFNat Commun
November 2024
Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3QR, UK.
Although not the only greenhouse gas, CO is the poster child. Unsurprisingly, therefore, there is global interest across industrial and academic research in its removal and subsequent valorisation, including to methanol and its surrogates. Although difficult to study, the heterogenous pnictogens represent one important category of catalytic materials for these conversions; their high crustal abundance and low cost offers advantages in terms of sustainability.
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