The strontium tantalate Sr₂Ta₂O₇ is a ceramic with an orthogonal Cmcm space group. Due to its potential applications in the field of multiferroics, it has become a research hotspot in recent years. However, the regulatory mechanism and phase transition behavior of hydrostatic pressure on its complex lattice structure remain unclear, which, to some extent, limits the in-depth understanding of the “structure-property” relationship of this material. This study systematically investigates the lattice dynamic response characteristics of orthogonal Cmcm Sr₂Ta₂O₇ under high pressure up to 30 GPa by using in-situ high-pressure Raman spectroscopy, marking the highest pressure on this system to date. The results manifest that when the pressure reaches 5 GPa, significant changes occur in the Raman vibrational modes of the material. This phenomenon is attributed to a commensurate-to-incommensurate structural transition induced by symmetry breaking, consistent with previous research findings on Sr₂Ta₂O₇. As the pressure further increasing to 20 GPa, a second phase transition may occur, which is identified as a first-order phase transition closely related to lattice disordering. However, the specific crystal structure of this high-pressure phase remains to be further confirmed in future studies. The Raman spectroscopy analysis suggests that the structural distortion of this high-pressure phase may follow a transformation pathway from orthogonal to monoclinic.

Mineral resources on Earth are finite, but wood is renewable. Therefore, replacing limited industrial materials with modified wood remains a long-term pursuit. This study processed samples of three wood types, including balsa (Ochroma lagopus), basswood (Tilia tuan), and African blackwood (Dalbergia melanoxylon), with a large volume cubic press to compress these samples at room temperature under high pressure. The effects of high-pressure treatment on the air dry density, compressive strength, and elastic modulus of the three wood species were analyzed, and changes in their internal microstructures were observed using CT and scanning electron microscope. The results showed that the physical and mechanical properties of all three wood species improved. After high-pressure processing at 5.50 GPa, the density of balsa, basswood, and African blackwood increased by 239%, 112%, and 11%, respectively. Additionally, the surface hardness increased by 79%, 46%, and 15%, respectively, and the compressive strength increased by 33%, 9%, and 28%, respectively. Notably, the specific strength of compressed African blackwood (101.55 kJ/kg) approaches that of aluminum alloys (109.23 kJ/kg). The results demonstrate that African blackwood is lighter than ceramic materials. Furthermore, this wood offers superior electrical insulation and thermal insulation compared to aluminum alloy. Crucially, African blackwood possesses high specific strength, and this property gives it significant potential to replace aluminum alloy in numerous special environments. Such application supports sustainable development for future industries. In conclusion, this research opens new possibilities for high-value wood applications.