There may also be substances such as unburned jet fuel that may have come from the two hijacked jetliners terrorists piloted into the buildings.

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My coffee is hot and yet my hands are unburned.

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Because hydrogen can clean the exhaust right from a cold engine start, the plasma reformer method is 20% to 50% more efficient at reducing NOx than other clean-diesel technologies, allowing less unburned fuel to pass through in the process.

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For now ArvinMeritor is marketing its plasma fuel reformer to the commercial trucking industry, which is scrambling to comply with tough new emission laws that are looming in Europe and the U.S. By 2007 the U.S. Environmental Protection Agency will require a 90% reduction in the amount of soot (unburned carbon).

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