Figure 2
From: Mechanics and physics of a glass/particles photonic sponge

Uniaxial compression test, with the preliminary UV irradiation being performed under load. A 4 × 4 × 4.47 mm3 parallelepiped sample was UV-irradiated for 30 s under a 26 MPa compression load. The sample was loaded for 1500 s, unloaded at 1500 s and further reloaded at 1575 s for 10 s. The inset shows the bar from which were cut the specimens for mechanical testing.