The Chinese puzzle ball is an ornate decorative artwork consisting of several concentric shells that move independently of each other. In the recent decade, Chinese scientists provided a universal ...
MR. G. W. WALKER tells me that he has sent to NATURE his interesting problem of the mutual attraction between two uniform concentric hemispherical shells, bounded by a common diametral plane. The ...
Diamond may be just a phase carbon goes through when exposed to a flash of heat, but that makes it far easier to obtain. The Rice University lab of chemist James Tour is now able to "evolve" carbon ...