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1·As Masurium, it was the first element discovered that occurs in nature only from spontaneous fission, and as Technetium, it was the first element discovered in a laboratory.

作为 Masurium，它是在自然界中发现的第一种只能通过自然裂变产生的元素；作为锝，它是在实验室中发现的第一种元素。

2·But they do not stop spontaneous fissions in fuel rods from fuel and fission products.

但他们并没有阻止自然地发生在来自核燃料和裂变产物的燃料棒上的裂变。