We're all familiar with the high-pitched squeak of basketball shoes on the court during games, or tires squealing on pavement. Scientists conducted several experiments and discovered that the geometry of the sneakers' tread patterns determines the squeak's frequency, enabling the team to make rubber blocks set to specific frequencies and slide them across glass surfaces to play Star Wars' "Imperial March."
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In a letter to its customers, Heraeus Medical said it had experienced a critical machine failure at its main site when it was in the process of upgrading its production processes.，详情可参考快连下载安装
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