Fig. 1: Examples of ultrasonic waveform and X-ray radiographic image of a fully molten sample.
From: Effect of sulfur on sound velocity of liquid iron under Martian core conditions
(a) Fe, (b), Fe80S20, and (c), Fe57S43. R1–R7 represent echo signals by 3-cycle sine-wave burst with a center frequency of 40 MHz from the following boundaries; R1 = anvil/buffer-rod, R2 = YSZ/sapphire, r2 = ZrO2/Al2O3 (surroundings), R3 = fronting sapphire/sample, R4 = sample/backing sapphire, R5 = sapphire/pressure marker (a) sapphire/c-BN (b, c), R6 = c-BN/pressure marker, R7 = pressure marker/MgO. See more detail in Supplementary Fig. 7. L in X-ray radiographic image represents sample length; 517.7(5) μm for Fe, 507.7(1) μm for Fe80S20 and 541.7(6) μm for Fe57S43. 2Δt in ultrasonic waveform represents two-way travel time in the sample; 221.1 ns for Fe, 217.0 ns for Fe80S20 and 241.7 ns for Fe57S43. Sound velocity (VP) can be obtained as L/Δt.
