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Showing 1 to 15 of 15 for “"Sound Velocities"”.
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Density, magnetic properties and sound velocities of iron-rich materials at high temperature and high pressure
… iron-carbon compounds, including the density and sound velocities, with the observed values of inner core, e.g., the values in preliminary reference Earth model (PREM) determined using normal mode data and seismic travel time data. In this work, I studied the density, elasticity, sound velocity …
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The Effect of Minor Elements on the Physical and Chemical Properties of Lower Mantle Minerals at High-Pressure
The sound velocities, elasticity, and crystal chemistry of minerals in Earth's lower mantle are of general importance for the interpretation of seismic wave observations, geochemical modeling, and geodynamic simulations. Aluminum-bearing (Mg,Fe)SiO3 perovskite and (Mg,Fe)O ferropericlase are …
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New high pressure phase transition of natural orthoenstatite and sound velocity measurements at simultaneous high pressures and temperatures by laser heating
Studies of phase transformations and sound velocities of candidate mantle minerals under high-pressure high-temperature conditions are essential for understanding the mineralogical composition and physical processes of Earth’s interior. Phase transitions in candidate deep earth minerals under …
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The third order elastic constants of aluminum
… and uniaxial stress derivatives of the natural sound velocities using a two specimen interferometric technique. The values obtained are ...in units of 101 2 dyn.cm -2 • I The specimens were neutron irradiated to eliminate dislocation effects~ from the uniaxial experiments. A se1fconsistent set …
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Measurement of the chemical potential of thin helium films
High-precision measurements of third sound velocities in atomically thin $\sp4$He films on Ar, Ne, CO$\sb2$, and H$\sb2$ substrates in the T = OK limit reveal a periodic structure not corresponding to whole layers. We analyze the data in two extreme limits. First, treating the helium film as an …
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Sound velocity study of natural orthopyroxenes with varying iron content
Determination of the acoustic wave velocities of orthopyroxene as a function of composition is essential to identify the underlying causes of seismic heterogeneity. Such laboratory measurements are essential to determine the structure, composition and temperature variability of the upper mantle. …
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Landau Model for Films and Interfaces of Superfluid Helium-4 at T = 0k
… and a film on a graphite substrate. The third-sound velocities c(,3) vs. (DELTA)(mu) show oscillations characteristic of the layer structure, which are consistent with measured data if a proper substrate potential is chosen. A possible form of the effective van der Waals potential of a graphite …
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Landau model for films and interfaces of superfluid 4HE at T=OK
… and a film on a graphite substrate. The third-sound velocities c3 vs. ~P show oscillations characteristic of the layer structure, which are consistent with measured data if a proper substrate potential is chosen. A possible form of the effective van der Waals potential of a graphite substrate, …
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The elastic properties of fine-grained polycrystalline and amorphous samples by Brillouin scattering
… Earth. In this study we have investigated the sound velocities and elastic properties of fine-grained polycrystalline and amorphous materials using Brillouin scattering. Our initial experiments were performed on silica minerals, among the most abundant minerals in the crust, and MgO, one of the …
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Elasticity across the post-stishovite transition in subducted basalt
… transition in MORB. Specifically, I measured sound velocities using Brillouin light scattering and impulsive stimulated light scattering, Raman shifts of optic modes using Raman spectroscopy, and atomistic properties using synchrotron single-crystal X-ray diffraction in diamond anvil cells at …
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The second and third order elastic constants of magnesium
… uniaxial compression derivatives of the natural sound velocities using an ultrasonic pulse superposition technique. The specimen was neutron irradiated to suppress dislocation effects. A theoretical model has been developed to predict the elastic constants of magnesium. The energy density of the …
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Elastic properties of mantle minerals by multiple methods and at high pressures and temperatures
Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2025-08-01
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Single-crystal elasticity of Al-rich phases in the Earth’s transition zone and lower mantle
… of lateral heterogeneity in seismic wave velocities. Seismic observations of the Earth’s interior provide the only method to investigate the mantle at the depth and scale required to understand its chemistry and structure and for tracing the chemical anomalies potentially caused by …
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Many-body localization and tensor networks
… to extract information on the central charges, sound velocities, and conformal dimensions. With the numerical data, we show the relation between the CFT contents of the critical chains with periodic boundary conditions and the critical chains with duality-twisted boundary conditions.