The route of toughening EP and BMI domestic and overseas at present is mainly rubber, thermoplastic, chain-extending and thermotropic crystalline polymer toughening.
But he has a place in history as the last naturally occurring case in a continuing chain of transmission extending back at least 3,500 years.
但他作为最后一个天然发生的天花病例的历史地位在继续扩展传播链要返回到3,500多年前。
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Extending the supply can also open companies up to considerable disruption if the links in the chain do not work, for example because of a global pandemic or a natural disaster in a crucial region.