<< Sand is a fascinating material. It can flow and be poured like a liquid, but retains many of the properties of solids, clogging pipes or forming sand dunes. (..) Grains interact via simple, Newtonian mechanics, but because so many particles are interacting at once, there is an emergent complexity of flow behavior that cannot yet be explained by simple equations. Scientists are thus not only looking for better theoretical models to explain granular behavior, but convenient "model systems" that can be handled and tuned in the lab to give insights into how the microscopic structure of granular materials gives rise to their macroscopic properties. >>️️
<< A team (..) has studied the properties of mixtures of silicone-coated "magic sand," a popular kids' toy, and normal sand. Silicone-coated sand particles were found to interact only with each other and not with other sand particles. The team discovered that adding silicone-coated sand beyond a certain threshold leads to an abrupt change in clustering and rigidity, a potential way to tune the flow of granular materials for industry.>>️
<< Using three independent methods involving sieving, measuring density and forming stable mounds of sand, they found that the mechanical properties of the mixture changes drastically when the fraction of magic sand to normal sand exceeds 20%. This agreed with findings from percolation theory, which governs how connections between particles span space without any breakages, letting the sand mixture behave in a significantly more solid-like way and bear its own weight. This behavior is known for polymer gels, and helps unify theoretical approaches applied to completely different materials. The team's mixtures also exhibits mechanical properties that can be easily modified. Importantly, the method provides a new, convenient, accurate and informative way to explore granular physics, >>️
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'Magic sand' might help us understand the physics of granular matter. Tokyo Metropolitan University. Mar 08, 2021.
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Marie Tani, Honoka Fujio, Rei Kurita. Transition Behavior in Silicone-coated Sand Mixtures. Journal of the Physical Society of Japan. 90 (3): 033801. doi: 10.7566/ JPSJ.90.033801.
Also
keyword 'grain' in FonT
keyword 'sand' in FonT
keyword 'sand' in Notes (quasi-stochastic poetry)
keyword 'sabbia' in Notes (quasi-stochastic poetry)
keyword 'grani' in Notes (quasi-stochastic poetry)
