Ballistite was a smokeless propellant that combined nitrocellulose and nitroglycerine.

弹道石是一种无烟推进剂，结合了硝化纤维素和硝化甘油。

But could the men have picked up nitrocellulose on the train?

那么，这些人是否可能上接触到了硝化纤维呢？

He used nitrocellulose, a flammable solid, created by mixing cotton with nitric acid to create a hard, shiny, white sphere.

他使用了硝化纤维素， 一种易燃固体，通过将花与硝酸混合制成坚硬、闪亮的白色球体。

By the middle of the century, American entrepreneurs discovered that dipping nitrocellulose in wax turned it into a hard, enduring substance, and patented it as celluloid.

到本世纪中叶，美国企业将硝化纤维素浸入蜡中会使其成为一种坚硬耐用的物质，并将其申请了赛璐珞专利。

It worked well once it was created, but the manufacturing process was dangerous because nitrated cellulose can explode in a warm breeze.

它一经创建就运作良好， 但制造过程很危险，因为硝化纤维素会微风中爆炸。

And when you expose cellulose, like in wood pulp or cotton, to nitric acid, it forms cellulose nitrate -- which is highly flammable.

当你将硝酸暴露纤维素上， 比如木浆或花中，它会形成硝化纤维素——这是一种极易燃烧的物质。

It proved that you've been handling something called nitrocellulose, which, yes, that is found in explosives, but it's also found in a number of other things, including playing cards.

这证明你接触过一种叫硝化纤维的东西，没错， 它炸药中存，但也存于其他多种物品中，比如扑克牌。