铜片

Copper plates are imported from Japan,pure silver ingots for plating from Switzerland,and argentic salt and other chemicals from Germany.

采用口的铜片，镀银用的瑞士纯银条，西德的银监及化工原料等等。

That achievement came at the Bevatron accelerator at Lawrence Berkeley National Laboratory, by smashing protons into a piece of copper.

在美国劳伦斯柏克莱国家实验室的贝加速器（Bevatronaccelerator）里，以质子撞击铜片便可以办得到。