Honeycomb bodies, honeycomb structures and extrusion dies, including a transition structural component. A honeycomb structure (100) includes a plurality of interconnected webs (106) defining a plurality of cell channels (108) in a honeycomb matrix (109) having a central axis (110) orthogonal to its transverse cross-section. Radial webs (116) diverge outwardly from the central axis (110). Radial webs (116) include a first radial web (150) and a second radial web (152). Tangential webs (120) are arranged concentrically with respect to the central axis (110), wherein at least one of the tangential webs (120) is a tangential transition web (142). At least one transition structural component (140) is located radially inward from the tangential transition web (124) and includes a first inclined web (144) having a first end (144A) coupled to the first radial web (150) and a second inclined web (146) having a first end (146A) coupled to the second radial web (152). Extrusion dies configured to make the honeycomb structures are provided, as are other aspects.

A method of preparing a catalyst composition for producing a stable ratio of NO.sub.2 to NO in an exhaust system of a compression ignition engine is described. The method comprises: (i) preparing a first composition comprising a platinum (Pt) compound disposed or supported on a support material; (ii) preparing a second composition by reducing the platinum (Pt) compound to platinum (Pt) with a reducing agent; and (iii) heating the second composition to at least 650° C.

A method for preparing a sol comprising TiO.sub.2 and ZrO.sub.2 and/or hydrated forms of TiO.sub.2 and ZrO.sub.2. The method includes mixing a material which includes metatitanic acid in an aqueous phase with a zirconyl compound or with a mixture of several zirconyl compounds. The material is provided either as a suspension or as a filter cake from the sulfate method. The material includes a H.sub.2SO.sub.4 content of 3 to 15 wt.-% relative to a quantity of TiO.sub.2 in the material. The zirconyl compound or the mixture of several zirconyl compounds is mixed in a quantity that is sufficient to provide the sol depending on the H.sub.2SO.sub.4 content.

A honeycomb body having a porous ceramic honeycomb structure with a first end, a second end, and a plurality of walls having wall surfaces defining a plurality of inner channels. A highly porous layer is disposed on one or more of the wall surfaces of the honeycomb body. The highly porous layer has a porosity greater than 90%, and has an average thickness of greater than or equal to 0.5 μm and less than or equal to 10 μm. A method of making a honeycomb body includes depositing a layer precursor on a ceramic honeycomb body and binding the layer precursor to the ceramic honeycomb body to form the highly porous layer.

The disclosure generally relates to filters, methods, and systems for filtering particulates from the exhaust of internal combustion engines such as gasoline direct injection engines and methods of preparing particulate filters.

A substrate (11) includes an inflow-side cell (21), an outflow-side cell (22), and a porous, gas-permeable partition wall (23) that separates the inflow-side cell (21) and the outflow-side cell (22) from each other, and also includes a first catalyst portion (14) that is provided on a side of the partition wall (23) that faces the inflow-side cell (21) at least at a portion in upstream side in an exhaust gas flow direction, and a second catalyst portion (15) that is provided on a side of the partition wall that faces the outflow-side cell at least at a portion in downstream side. With respect to a pore volume of pores with a pore size of 10 to 18 μm, when a measured value of the pore volume in the first catalyst portion (14) and the partition wall (23) within a region where the first catalyst portion (14) is provided is defined as a first pore volume, and a measured value of the pore volume in the second catalyst portion (15) and the partition wall (23) within a region where the second catalyst portion (15) is provided is defined as a second pore volume, the first pore volume is greater than the second pore volume. A catalytically active component contained in the first catalyst portion (14) and a catalytically active component contained in the second catalyst portion (15) are of different types.

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.

A honeycomb filter including: a pillar-shaped honeycomb structure having an inflow end face and an outflow end face and including a porous partition wall disposed so as to surround a plurality of cells, the plurality of cells extending from the inflow end face to the outflow end face; inflow side plugging portions disposed at open ends of predetermined cells on the inflow end face side; and outflow side plugging portions disposed at open ends of residual cells on the outflow end face side, wherein the outflow side plugging portions comprise first outflow side plugging portions and second outflow side plugging portions, the plugging length L1 of the first outflow side plugging portions is 10 to 50% of the overall length L0 of the honeycomb structure, and the plugging length L2 of the second outflow side plugging portions is less than 10% of the overall length L0 of the honeycomb structure.

A honeycomb structure, including: a plurality of pillar shaped honeycomb segments, each of the pillar shaped honeycomb segments including a partition wall and a plugged portion; and a joining layer arranged so as to join side surfaces of the pillar shaped honeycomb segments to each other. The honeycomb structure satisfies the following equations (1) to (3):

y≤1000  (1);

y≤717.92x.sup.−0.095  (2); and

y≥462.4x.sup.−0.153  (3),

in which y is a maximum temperature (° C.) at which the use of the honeycomb structure is accepted, and x is a thermal conduction factor represented by the following equation:

thermal conduction factor=(thermal conductivity of the partition wall×thermal conductivity of the joining layer)/(average thickness of the joining layer×porosity of the partition wall).

A honeycomb structure includes a pillar-shaped honeycomb structure body having porous partition walls surrounding a plurality of cells which extend from a first to a second end face and which form flow channels of a fluid, and a circumferential wall enclosing the partition walls, wherein, specific cell of the cells is provided with a pair of projection which projects into the cell from the partition wall, the projection projects, in at least a pair of opposed partition walls among the partition walls constituting the cell, into the cell from a first and a second side, and which is provided continuously in a direction the cell extends, and in the case where the width of a top part of the projection is denoted by W1, and the width of a bottom part of the projection is denoted by W2, W1>W2 holds, and W2/W1 is 0.5 to 0.9.