Difluoroboron avobenzone (BF(2)AVB), a simple boron complex of a commercial sunscreen product, exhibits morphology-dependent emission and mechanochromic luminescence in the solid state. When scratched, smeared, or even gently touched, the emission color of BF(2)AVB films is significantly red-shifted under UV excitation. In the rubbed regions, the fluorescence recovers slowly at room temperature or much faster with heating, resulting in a simple rewritable "scratch the surface" ink of potential commercial use.

Structural origin of the high glass-forming ability (GFA) in multicomponent bulk metallic glasses (BMGs) caused by minor alloying was investigated using state-of-the-art synchrotron radiation techniques. It is found that a two-shell icosahedral cluster with one Y center is the basic structural unit in the representative Cu46Zr42Al7Y5 BMG, which may be densely packed with the help of shared and glue atoms, leading to enhanced ordering at short and medium range. This cluster dense packing may play a key role in achieving the high GFA in CuZrAlY alloy, which also explains the strong dependence of GFA on Y content observed in many experiments. The present work may be extended to a series of multicomponent amorphous alloys, the formation of which is strongly dependent on minor alloying.

In order to eliminate filiform defects in high-pressure and high-temperature synthetic diamonds, we have developed a gradient cooling technology and applied it during the synthesis assembly cooling process used during the later stage of diamond synthesis. Finite element simulations showed that the von Mises stress at the end of the synthesis process varied greatly inside the diamond. The rapid thermoelastic stress relief and higher thermoelastic stress generated inside the diamond during rapid cooling of synthesis assembly were the root causes of filiform defects, which were completely eliminated from the diamond interior at a gradient cooling time of 300 min. Raman measurements indicated that the crystalline quality was higher and the compressive stress was lower in the diamond obtained using gradient cooling technology than in the diamond obtained using the traditional rapid cooling technology. This work improves the understanding of the origin of filiform defects in diamond and also provides an effective method for obtaining high-quality diamonds.

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