A combustion chamber assembly unit for a fuel-operated vehicle heater includes a combustion chamber housing (14) elongated in a direction of a housing longitudinal axis (L), with a combustion chamber (16) radially outwardly bounded by a circumferential wall (18), and with a combustion chamber bottom (20) axially delimiting the combustion chamber (16). A combustion air feed volume (36) is provided that is open to the combustion chamber (16) via a plurality of passage openings (38). A cooling medium feed device (46) is provided for feeding a liquid cooling medium to the combustion air feed volume (36).

The purpose of the present invention is to provide a metal-substituted beta zeolite that exhibits a more excellent catalytic performance than conventional one, and a method for producing the same. The present invention provides a metal-substituted beta zeolite by subjecting an alkali metal-form beta zeolite produced without using an organic structure-directing agent to ion exchange with ammonium ion and then, using a filter cake procedure, to ion exchange with copper ion or iron(II) ion. The present invention also provides a metal-substituted beta zeolite which has been ion exchanged with copper ion or iron(II) ion and in which the amount of Lewis acid sites is greater than the amount of Bronsted acid sites when the amount of Bronsted acid sites and the amount of Lewis acid sites are measured by ammonia infrared-mass spectroscopy temperature-programmed desorption on the as-produced state.

The present disclosure relates to a nanocrystal composite includes a connected aggregate including a plurality of nanocrystal fragments connected to one another, each nanocrystal fragment having a main surface and an end surface, and nanoparticles supported on the connected aggregate. The plurality of nanocrystal fragments each have a flaky shape; the plurality of nanocrystal fragments have gaps between the main surfaces; and the gaps G are arranged so as to open to the outside of the connected aggregate. The nanoparticles have a metallic element different from that of the plurality of nanocrystal fragments; and a proportion of a visual field area of the nanoparticles with respect to a visual field area of the plurality of nanocrystal fragments is 2% or more and 50% or less.

An abnormality determination apparatus for an ammonia sensor is usable in an exhaust purification system including a catalyst, a supply apparatus, an ammonia sensor, an NO.sub.X sensor, and an oxygen sensor. During a continuation period within which ammonia supply to the catalyst continues after the supply apparatus stops supply of reductant, the abnormality determination apparatus calculates the ammonia concentration on a downstream side of the catalyst as a first concentration value, based on an output of the ammonia sensor and an output of the oxygen sensor. During the continuation period, the abnormality determination apparatus calculates the ammonia concentration on the downstream side of the catalyst as a second concentration value, based on an output of the NO.sub.X sensor and the output of the oxygen sensor. The abnormality determination apparatus determines presence or absence of abnormality in the ammonia sensor based on the first concentration value and the second concentration value.

A pillar-shaped honeycomb structure including an outer peripheral side wall, a plurality of first cells provided on an inner peripheral side of the outer peripheral side wall, the first cells extending from a first end surface to a second end surface, each opening on the first end surface and having a sealing portion with an average void ratio of 4% or less on the second end surface, and a plurality of second cells provided on the inner peripheral side of the outer peripheral side wall, the second cells extending from the first end surface to the second end surface, each having a sealing portion with an average void ratio of 4% or less on the first end surface and opening on the second end surface, the first cells and the second cells being alternately arranged adjacent to each other with a partition wall interposed therebetween.

The invention relates to a catalytic article comprising a substrate having an inlet and an outlet; a first coating comprising a blend of: (1) platinum on a support, and (2) a first SCR catalyst comprising a Cu- and Mn-exchanged molecular sieve; and a second coating comprising a second SCR catalyst; wherein the support comprises at least one of a zeolite or a SiO.sub.2-Al.sub.2O.sub.3 mixed oxide. The platinum may be fixed on the support in solution.

A honeycomb structure comprising a pillar-shaped honeycomb structure body having a porous partition wall disposed so as to surround a plurality of cells, wherein let that A denotes an absolute value of open frontal area (%) in a plane of the honeycomb structure body orthogonal to the extending direction of the cells and P denotes an absolute value of porosity (%) of the partition wall, the honeycomb structure has a value represented by the following expression (1) that is 0.05 to 0.12, let that D denotes an average pore diameter (m) of the partition wall and G denotes a geometric surface area (mm.sup.2/mm.sup.3) of the partition wall, the honeycomb structure has a value represented by the following expression (2) that is 8 to 50 (μm×mm.sup.2/mm.sup.3), and the honeycomb structure has a hydraulic diameter of the cells that is 1.1 mm or more,

(1−A/100)×(1−P/100),  Expression (1)

D×G.  Expression (2)

A dosing composition and method for treatment of reductant urea solutions utilizing organometallic catalyst precursors in combination with one or more surfactants to promote decomposition of relatively high molecular weight deposits which deposits may otherwise reduce selective catalytic reduction efficiency.

An engine system includes a hydrogen combustion engine and an exhaust aftertreatment system, EATS, configured to reduce emissions of the engine exhausts. The EATS comprises: an exhaust gas inlet for receiving engine exhaust from the hydrogen combustion engine; a plurality of emission reducing modules arranged downstream of the exhaust gas inlet and being configured to reduce emissions of the engine exhausts, the plurality of emission reducing modules comprising at least a first emission reducing module with a porous substrate including a powder coating and a selective catalyst reduction, SCR, coating, and a second emission reducing module being a selective catalyst reduction, SCR, catalyst unit. At least one of the first and second emission reducing modules is arranged as the first occurring emission reducing module of the EATS downstream of the exhaust gas inlet.

An aftertreatment system comprises an aftertreatment component. An outlet sensor is positioned downstream of the aftertreatment component. A controller is communicatively coupled to the outlet sensor. The controller is configured to interpret an outlet signal from the outlet sensor. The outlet signal is indicative of a performance of the aftertreatment component. The controller determines if the aftertreatment component has deactivated. In response to determining that the aftertreatment component has deactivated, the controller provides a catalyst active material to at least a portion of the aftertreatment component. The catalyst active material coats at least the portion of the aftertreatment component so as to remanufacture the aftertreatment component.