He and his team grew tiny polystyrene spheres until they were some 200 nanometres across, before hardening them with a blast of heat.
他和他的团队，先培育聚苯乙烯球直到它们的直径为200纳米，再用一股强热将其硬化。
2
Unfortunately, though flat tappets from China are cheap, their metallurgy is suspect-and the same goes for the quality of their machining, heat treatment and surface-hardening.