后来，他的一个朋友发现在橡胶里掺入硫磺，经过日晒，可以使橡胶变得又硬又结实。

Later, a friend of his had the idea that rubber might be made hard and strong if mixed with sulphur and put in the sun.

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模压和捏造硬橡胶和软橡胶以及手工制作的橡胶制品产品展示与硫化技术，检测和检查，测量和标准以及。

Molded and fabricated products of ebonite and soft rubber as well as hand-made rubber products are shown along with vulcanization technology, testing and inspections, measurements and standards.

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