Table 4: Characteristics of the nanoceramics under study*.

Specimen 𝑅 a g , nm 𝑅 g r , nmCSA, nmD at 3.8 K 𝑙 g b , nm 𝜌 2 𝑣 2 / 𝜌 1 𝑣 1

12010250 8639.001.500.70
21830273 90 8.071.500.80
31747232 9652.001.280.85
4141423615029.500.270.60
5203726015057.000.350.70
6171126314870.501.100.85

𝑅 a g is the agglomerate size; 𝑅 g r is the grain size; 𝑅 C S A are coherent scattering areas in the specimens according to the XPS, AFM, and SEM data; D is the effective diffusion coefficient; 𝑙 g b is the interface region thickness; 𝜌 2 𝑣 2 / 𝜌 1 𝑣 1 is the acoustic impedance.