He realised that achieving power generation means juggling temperature, density and the time for which the reaction can be prolonged.

他意识到，实现发电意味着兼顾温度、密度和反应可以延长的时间。

The speed of these waves, for example, is linked to the temperature, density and chemical composition of the rocks in the core and mantle.

例如，这些波的速度与地核和地幔中岩石的温度、密度和化学成分有关。