| 摘要 |
<p>An improved puck has a structural material in the general shape of a disk and a thermochromic visualization agent associated with the disk. Generally, at least a portion of the visualization agent is visually observable. The visualization agent generally can be, for example, incorporated into the material of the puck or applied as a coating onto the surface of the puck. Methods for playing a sporting activity can comprise evaluating an object used in the sporting activity to determine if the object is at a suitable temperature for playing.</p> |
