NOVELTY - The method involves absorbing at least part of nitrogen oxide from the lean nitrogen oxide-containing diesel emission to form a substantially nitrogen oxide-free lean diesel emission, introducing an exotherm generating agent into the emission to form a reactive lean diesel emission, using the emission to generate heat for desorbing part of absorbed nitrogen oxide and for producing a lean, desorbed nitrogen oxide emission, introducing a reducing agent into the emission, and remediating the emission to obtain the remediated diesel emission.    USE - Method for remediating nitrogen oxide-containing lean diesel emissions. Can also be used for emissions emanating from combustion processes such as found in a diesel truck, a gasoline-powered vehicle, a portable hydrocarbon-powered device, such as a generator, a lawn mower, a snowmobile, a chain saw, as well as a one-, two-, or four-cycle engine, an electric power generation plant, a gas turbine, an airplane, a locomotive, a boat, a personal watercraft, and a ship, and a hybrid power system such as a vehicle intermittently using a combustion process with other power sources such as electricity, liquefied petroleum gas, natural gas, fuel cells, and solar power.    ADVANTAGE - Introducing the exotherm generating agent and reducing agent into the diesel emissions improve the remediation of the emission stream when exposing the emissions to the lean nitrogen oxide trap and selective catalytic reduction catalyst and make the entire method suited for lean air-to-fuel ratio conditions for relatively wide range of temperature and nitrogen oxide concentrations in the emissions. Introducing the exotherm generating agent, such as fuel, periodically or only as needed to increase the emissions temperature avoids use of relatively greater amounts of expensive fuel to alter the emissions from lean to rich air-to-fuel ratios. Placing the introduction port for reducing agent downstream or upstream of the lean nitrogen oxide trap prevents oxidation of the agent over the trap or prevents hydrocarbons from deteriorating effectiveness of selective catalytic reduction.    DETAILED DESCRIPTION - The method involves absorbing at least part of nitrogen oxide from the lean nitrogen oxide-containing diesel emission on one of two lean nitrogen oxide traps in a lean nitrogen trap/selective catalytic reduction catalyst system (14) to form a substantially nitrogen oxide-free lean diesel emission, introducing an exotherm generating agent, such as fuel, to the emission between the traps for a given time period to form a reactive lean diesel emission, introducing the emission to the other trap to generate heat for desorbing part of absorbed nitrogen oxide from the trap and produce a lean, desorbed nitrogen oxide emission, streaming the emission downstream from the exit of the other trap, introducing a reducing agent, such as ammonia, into the emission between the other trap and the selective catalytic reduction catalyst for a given time period, and remediating the emission on the catalyst to obtain the remediated diesel emission. An INDEPENDENT CLAIM is also included for a lean nitrogen oxide trap/ selective catalytic reduction catalyst control system for remediating a nitrogen oxide-containing lean diesel emission having a direction of flow and an inlet temperature sensor.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic diagram of a remediation system installed on a truck.    Engine (2)    Casing (6)    Lean nitrogen trap/selective catalytic reduction catalyst system (14)    Introduction ports (16,18)    Emissions outlet (20)