The united states had more than 133 million diesel trucks on its roadways in 2012.

2012年，美国公路上有超过一点三三亿辆柴油卡车。

You don't want to inhale the byproducts of combustion, whether it's from a cigarette, a wildfire, a diesel truck or a coal-fired power plant.

你不想吸入燃烧的副产品，无论是来自香烟、野火、柴油卡车还是燃煤电厂。

And then he kind of stumbled upon this idea of retrofitting diesel trucks so that they could also, like partially run on natural gas, a cleaner form of energy.

然后他偶然发现了改装柴油卡车的想法，这样它们也可以像部分使用天然气一样使用更清洁的能源。

Black carbon is a type of particle that is black but what it really measures is diesel pollution, that the black plume that comes out of like a heavy-duty diesel truck or a bus.

黑碳是一种黑色的颗粒物，但它真正测量的是柴油污染，重型柴油卡车或公共汽车排放出来的黑色烟羽。