Recent experimental studies have shown that anelasticity of polycrystalline materials is subject to the Maxwell frequency (f M ) scaling:However, the applicability of this scaling to the seismic waves has not been guaranteed because experimental frequencies normalized to f M of the laboratory samples are usually much lower than the seismic frequencies normalized to f M in the upper mantle (10 6 ≤ f ∕f M ≤ 10 9 ). In this study, by using polycrystalline organic borneol as an analogue to mantle rock, we measured anelasticity up to f ∕f M ≃ 10 8 and found that the Maxwell frequency scaling is not fully applicable at f ∕f M > 10 4 . A closer examination showed that each of the relaxation spectra obtained under various temperature, grain size, and chemical composition can be represented by the superposition of a background dissipation subject to the Maxwell frequency scaling and a peak dissipation centered at f ∕f M ≃ 10 3 . Significant increases of the peak amplitude and width with increasing temperature, grain size, and impurity content result in failure of the Maxwell frequency scaling at f ∕f M > 10 4 , where the peak dissipation dominates over the background dissipation. The peak is significantly broadened near the solidus temperature (T∕T melt = 0.93), producing an absorption band toward the normalized seismic frequencies. The absorption band suggested by the present data is characterized by variable amplitude and width, indicating a nonlinear reduction of seismic velocity near the solidus.

The Fe/CeO2 catalyst showed a high activity for reverse water gas shift (RWGS) reaction. Almost no loss of RWGS activity on Fe/CeO2 catalysts even in reaction atmospheres containing high concentrations of hydrogen sulfide.