摘要:
A diagnostic system and method for diagnosing the performance of a particulate matter (PM) filter of an exhaust system each involve receiving, by a controller from at least one sensor, a gas component measurement of exhaust gas flowing through the exhaust system and the PM filter. The controller calculates a conversion efficiency of the gas component by the PM filter and compares the calculated conversion efficiency to a predetermined conversion efficiency threshold indicative of an expected conversion efficiency of a flow-through catalyst. The controller then determines whether the PM filter is cracked or damaged based on the comparison between the calculated conversion efficiency and the predetermined conversion efficiency threshold.
摘要:
A diagnostic system and method for diagnosing the performance of a particulate matter (PM) filter of an exhaust system each involve receiving, by a controller from at least one sensor, a gas component measurement of exhaust gas flowing through the exhaust system and the PM filter. The controller calculates a conversion efficiency of the gas component by the PM filter and compares the calculated conversion efficiency to a predetermined conversion efficiency threshold indicative of an expected conversion efficiency of a flow-through catalyst. The controller then determines whether the PM filter is cracked or damaged based on the comparison between the calculated conversion efficiency and the predetermined conversion efficiency threshold.
摘要:
An exhaust system for a vehicle includes a passageway, a selective catalytic reduction system, a diesel particulate filter, a urea injection system, and a hydrolysis catalyst. The passageway is operable to direct a flow of exhaust gas emitted from an engine of the vehicle. The selective catalytic reduction system and the diesel particulate filter are positioned along the passageway spaced from one another. The urea injection system includes an injection port positioned along the passageway upstream of the selective catalytic reduction system. The urea injection system is operable to inject urea into the passageway. The hydrolysis catalyst coats at least a portion of the diesel particulate filter. Urea injected into the passageway through the injection port decomposes into ammonia and carbon dioxide upon contact with the hydrolysis catalyst. Thus, the decomposition of the urea is not dependent on mixing the urea with the exhaust gases.
摘要:
This invention relates to a semiconductor device comprising at least one p-n junction. The junction is formed from a "p" semiconductor contacting an "n" semiconductor. Said device characterized in that at least one of said "p" or "n" semiconductor is a nanoporous crystalline semiconducting material. These nanoporous materials have an intracrystalline nanopore system whose pores are crystallographically regular and have an average pore diameter of about 2.5 to about 30 .ANG.. Additionally, they have a band gap of greater than 0 to about 5 eV which band gap can be modified by removing a portion of the templating agent from the pore system of the materials. The materials which have these properties include, metal polychalcogenide compounds, metal sulfides and selenides, metal oxides, and metal oxysulfides. These materials can be used in a large variety of semiconducting devices such as light emitting diodes, bipolar transistors, etc. A process for preparing these nanoporous materials is also presented.