Controlling exhaust after-treatment in a heavy-duty motor vehicle includes operating a diesel engine of a heavy-duty truck such that the diesel engine generates an exhaust gas flow that enters an exhaust after-treatment system of the heavy-duty truck, the exhaust after-treatment system including a selective catalytic reduction system, measuring a level of NO.sub.x gases in the exhaust gas flow downstream of the selective catalytic reduction system, and controlling a diesel exhaust fluid injector upstream of the selective catalytic reduction system to inject diesel exhaust fluid into the exhaust gas flow upstream of the selective catalytic reduction system at an injection rate that is based on the measured level of NO.sub.x gases.

An exhaust passage includes a main passage and bypass passage, a catalyst, an exhaust control valve, and an HC adsorbent in the bypass passage. The exhaust control valve is controlled so that, when a temperature of the catalyst is higher than a predetermined sintering occurrence temperature, the quality of HC desorbed from the HC adsorbent is greater when the air-fuel ratio of the exhaust gas flowing through the upstream exhaust passage portion is a lean air-fuel ratio compared to when it is a stoichiometric air-fuel ratio or rich air-fuel ratio, or the quality of HC desorbed from the HC adsorbent is greater when the air-fuel ratio of the exhaust gas flowing through the upstream exhaust passage portion is a larger lean air-fuel ratio compared to when it is a smaller lean air-fuel ratio.

A method is presented for facilitating oxygen vacancy generation in a resistive random access memory (RRAM) device. The method includes forming a RRAM stack having a first electrode and at least one sacrificial layer, encapsulating the RRAM stack with a dielectric layer, constructing a via resulting in removal of the at least one sacrificial layer of the RRAM stack, the via extending to a high-k dielectric layer of the RRAM stack, and forming a second electrode in the via such that the second electrode extends laterally into cavities defined by the removal of the at least one sacrificial layer.

Passive NO.sub.x adsorption (PNA) compositions have a formula Pd—NiFe.sub.2O.sub.4 wherein Pd represents a palladium component, such as palladium oxide, that is adsorbed on surfaces of the nickel ferrite. Such compositions can be synthesized by wet impregnation of nickel ferrite with a palladium salt, and exhibit efficient NO.sub.x adsorption at low temperature, with NO.sub.x desorption occurring predominantly at high temperature. Two-stage NO.sub.x abatement catalysts, effective under engine cold start conditions, include a PNA composition upstream from an NO.sub.x conversion catalyst.

An exhaust aftertreatment device includes a housing defining an inlet and an outlet. A plurality of first substrate layers are positioned within the housing in fluid receiving communication with the inlet. The plurality of first substrate layers define a first flow direction, and the plurality of first substrate layers comprise a passive NOx adsorber washcoat. A plurality of second substrate layers are positioned within the housing with the first and second substrate layers being layered in alternating order. The plurality of second substrate layers define a second flow direction perpendicular to the first flow direction, and the plurality of second substrate layers comprise a selective catalytic reduction washcoat. A connecting passage is in fluid receiving communication with the plurality of first substrate layers and in fluid providing communication with the plurality of second substrate layers.

This disclosure is directed to catalyst compositions, catalytic articles for purifying exhaust gas emissions and methods of making and using the same. In particular, the disclosure relates to a catalytic article including a catalytic material on a substrate, wherein the catalytic material has a first layer and a second layer. The first layer provides effective lean NO.sub.x trap functionality and the second layer provides effective three-way conversion of carbon monoxide, hydrocarbons, and nitrogen oxides (NO.sub.x).

Provided is a catalyst for exhaust gas purification, the catalyst comprising: a noble metal; an alumina support particle; and a ZrO.sub.2 semiconductor support particle deposited on a surface of the alumina support particle.

An exhaust passage includes a main passage and bypass passage, a catalyst, an exhaust control valve, and an HC adsorbent in the bypass passage. The exhaust control valve is controlled so that, when a temperature of the catalyst is higher than a predetermined sintering occurrence temperature, the quality of HC desorbed from the HC adsorbent is greater when the air-fuel ratio of the exhaust gas flowing through the upstream exhaust passage portion is a lean air-fuel ratio compared to when it is a stoichiometric air-fuel ratio or rich air-fuel ratio, or the quality of HC desorbed from the HC adsorbent is greater when the air-fuel ratio of the exhaust gas flowing through the upstream exhaust passage portion is a larger lean air-fuel ratio compared to when it is a smaller lean air-fuel ratio.

The present invention relates to a process for preparing a zeolitic material having a framework type FER and having a framework structure comprising silicon, aluminum, and oxygen, said process comprising (i) preparing an aqueous synthesis mixture comprising water; a zeolitic material having a framework type other than FER and having a framework structure comprising silicon, aluminum, and oxygen; a source of silicon other than the zeolitic material having a framework type other than FER; an organic structure directing agent comprising piperidine; a source of an alkali metal; and a source of a base; (ii) subjecting the aqueous synthesis mixture prepared according to (i) to hydrothermal synthesis conditions comprising heating the synthesis mixture to a temperature in the range of from 140 to 190° C. and keeping the synthesis mixture at a temperature in this range under autogenous pressure, obtaining a mother liquor comprising a solid material which comprises the zeolitic material having a framework type FER.

A nitrogen oxide storage material comprising: Mg.sub.1−yAl.sub.2O.sub.4−y, wherein y is a number satisfying 0≤y≤0.2, a noble metal, an oxide of a metal other than the noble metal, and a barium compound, the noble metal, the oxide, and the barium compound being loaded on Mg.sub.1−yAl.sub.2O.sub.4−y. The metal oxide comprises at least one metal oxide selected from zirconium oxide, praseodymium oxide, niobium oxide, and iron oxide.