Injected into the exhaust stream, the solution's ammonia reacts in the de-NOx catalyzer to form nitrogen and water vapor.

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These include the exhaust gases such as nitrogen oxides (NOx), non-methane volatile organic compounds (NMVOCs), and carbon monoxide (CO).

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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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These gases are then used to clean up smog-producing nitrogen oxides, or NOx.

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That is, what do we get from a doubling of atmospheric CO2 (or more accurately, CO2-e, the effects of methane, NOX and so on converted to a common as if they were CO2 number).

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By optimizing the split-cycle concept, the Scuderi engine is expected to reduce NOx emissions up to 80 percent and improve fuel efficiency by 50 percent, compared to a conventional gasoline engine.

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Also, to comply with prevailing U.S. emissions standards on nitrogen oxides, or NOx, these big diesels require fairly complicated systems of postcombustion treatment with a water-based urea solution, called AdBlue.

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Scuderi says its split-cycle engine increases overall efficiency by up to 50 percent and cuts down on NOx gases at the same time by changing the way air gets channeled through an engine.

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