Abstract: A honeycomb structure includes at least one honeycomb unit. The at least one honeycomb unit has a longitudinal direction and includes plural cell walls extending from one end face to another end face along the longitudinal direction to define plural cells. The at least one honeycomb unit includes inorganic particles, an inorganic binder, and inorganic fibers. A degree of orientation of the inorganic fibers in an a-axis direction parallel to the longitudinal direction is about 0.5 or less.

Abstract: A honeycomb structure includes at least one honeycomb unit. The honeycomb unit includes plural cell walls to define plural cells, about 61 to about 70 mass % of zeolite, about 15 to about 25 mass % of an inorganic fiber, and about 10 to about 20 mass % of alumina other than alumina included in the zeolite and the inorganic fiber. The honeycomb unit has an opening ratio (%) of about 57% or more. The opening ratio is equal to or less than y shown in a formula of y=0.55x+30 when a content x (mass %) of the zeolite included in the honeycomb unit is less than about 66 mass %. The opening ratio is equal to or less than y shown in a formula of y 32 ?0.25x+82.8 when the content x (mass %) is about 66 mass % or more.

Abstract: A honeycomb structure includes an inorganic particle, inorganic binder, a honeycomb unit, a first end face, and a second end face. The honeycomb unit includes plural partition walls extending along a longitudinal direction of the honeycomb unit to define through-holes. The first end face is substantially perpendicular to the longitudinal direction and provided at a first end of the honeycomb structure. The second end face is substantially perpendicular to the longitudinal direction and provided at a second end opposite to the first end in the longitudinal direction of the honeycomb structure. First circularity of the first end face and second circularity of the second end face are about 1.5 mm to about 4.0 mm. The circularity of the first end face is different from the circularity of the second end face.

Abstract: A honeycomb structure includes at least one honeycomb unit and a peripheral wall at a peripheral surface connecting one end face and another end face of the honeycomb structure. The honeycomb unit includes inorganic particles, an inorganic binder, and cell walls extending along a longitudinal direction of the at least one honeycomb unit to define cells. The at least one honeycomb unit has a b-axis compression strength of about 1.0 MPa or less. A thickness T of the peripheral wall of the honeycomb structure is larger than 0.42V-0.25 (mm), where V is a volume of the honeycomb structure and in a range from about 1.0 liters to about 10 liters.

Abstract: A honeycomb structure includes a honeycomb unit containing zeolite and an inorganic binder and having cell walls extending from one end to another end along a longitudinal direction of the honeycomb unit to define cells. An amount of zeolite contained per apparent unit volume of the honeycomb unit is approximately 230 g/L or more. A thickness X mm of the cell walls is in a range from approximately 0.15 mm to approximately 0.35 mm. A mathematical formula 40X+20?Y?40X+30 is satisfied when a porosity of the cell walls is defined as Y %.

Abstract: A honeycomb structure includes at least one honeycomb unit and a coat layer provided at a peripheral surface of the honeycomb structure. The honeycomb unit includes zeolite, an inorganic binder, and cell walls extending from a first end face to a second end face of the honeycomb unit along a longitudinal direction of the honeycomb unit to define cells. A ratio ?c/?h is equal to or larger than about 0.75 and equal to or smaller than about 1.25. Ec/Eh is equal to or larger than about 0.75 and equal to or smaller than about 1.25. The ?c and ?h are coefficients of thermal expansion of the coat layer and the honeycomb unit, respectively, in a radial direction of the honeycomb structure. The Ec and Eh are Young's moduli of the coat layer and the honeycomb unit, respectively, in the radial direction of the honeycomb structure.

Abstract: A honeycomb structure includes at least one honeycomb unit. The at least one honeycomb unit includes zeolite, inorganic binder, and cell walls extending from a first end face to a second end face along a longitudinal direction of the at least one honeycomb unit to define cells. The at least one honeycomb unit includes a cross-sectional surface orthogonal to the longitudinal direction having a substantially square shape. An aperture ratio of the at least one honeycomb unit is in a range from about 50% to about 65%. A formula 12.5V+50<Lc/wc<12.5V+200 is satisfied, where V (liter) denotes the volume of the honeycomb structure and the wc (cm) and Lc (cm) denote a cell width and a total length of the cells, respectively.

Abstract: A honeycomb structure includes a honeycomb unit having inorganic particles, an inorganic binder and inorganic fibers. A value of (D90-D10)/D50, which indicates a length distribution of the inorganic fibers, is about two or less, where, when the fiber length is taken in a horizontal axis and a volume frequency is taken in a vertical axis, D10 is a fiber length at 10% by volume, D50 is a fiber length at 50% by volume, and D90 is a fiber length at 90% by volume, where D10<D50<D90.

Abstract: A honeycomb structure includes a honeycomb structure includes a honeycomb unit. The honeycomb unit has thermal conductivity equal to or greater than about 0.15 W/m/K but less than or equal to about 0.60 W/m/K and has Young's modulus equal to or greater than about 1.5 MPa but less than or equal to about 7.0 Mpa. The honeycomb unit includes zeolite, an inorganic binder, and partition walls. The partition walls extend along a longitudinal direction of the honeycomb unit to define plural through holes.

Abstract: A honeycomb structure includes at least one honeycomb unit including zeolite, an inorganic binder, and cell walls. The cell walls extend from a first end face to a second end face to define cells along a longitudinal direction of the at least one honeycomb unit. Each of the cell walls includes a center part in the longitudinal direction and a first end part adjacent to the first end face. The first end part has a thickness larger than a thickness of the center part, and/or the first end part has a porosity smaller than a porosity of the center part.

Abstract: A honeycomb structure includes at least one honeycomb unit. The at least one honeycomb unit has cell walls extending from one end face to another end face of the at least one honeycomb unit along a longitudinal direction of the at least one honeycomb unit to define cells. The at least one honeycomb unit includes zeolite, inorganic particles, and inorganic binder. The zeolite includes a hydroxyl group. The inorganic particles includes a hydroxyl group. A hydroxyl group content in the inorganic particles is greater than a hydroxyl group content in the zeolite.

Abstract: A honeycomb structure includes a center area, an outer peripheral area, and at least one honeycomb unit having a longitudinal direction. The center area has a smaller similarity shape in relation to a peripheral shape of the honeycomb structure in a cross section perpendicular to the longitudinal direction. The smaller similarity shape is defined by including a center of the honeycomb structure and substantially a half of a length from the center to the peripheral shape of the honeycomb structure. The outer peripheral area is located outside the smaller similarity shape. An aperture ratio of the honeycomb structure is from approximately 50% to approximately 65% in the cross section of the honeycomb structure. The aperture ratio includes a first aperture ratio in the outer peripheral area and a second aperture ratio in the center area. The first aperture ratio is larger than the second aperture ratio.

Abstract: A honeycomb structure includes at least one honeycomb unit having a longitudinal direction and including cell walls extending along the longitudinal direction from one end face to another end face to define cells. The at least one honeycomb unit includes inorganic particles, inorganic binder, and inorganic fibers. The inorganic fibers include a bio-soluble inorganic compound.

Abstract: A honeycomb structure includes at least one honeycomb unit which includes walls. The walls have a thickness of from about 0.10 mm to about 0.50 mm and extend along a longitudinal direction of the honeycomb structure to define through-holes. The honeycomb structure has a center area inside a boundary line passing through positions located at substantially a half of a length from a center of the honeycomb structure to a periphery of the honeycomb structure in a cross section perpendicular to the longitudinal direction. The honeycomb structure has a peripheral area outside the boundary line. A thickness of the walls located in the peripheral area is larger than a thickness of the walls located in the center area. A first opening ratio in the center area in the cross section is larger than a second opening ratio in the peripheral area in the cross section.

Abstract: A honeycomb structure includes a honeycomb unit which has zeolite, inorganic binder, and cell walls extending from one end to another end along a longitudinal direction of the honeycomb unit to define cells. An amount of zeolite contained per apparent unit volume of the honeycomb unit is approximately 230 g/L or more. Mathematical formulae [1] and [2] are satisfied when a thickness of the cell walls is defined as X mm and an average pore diameter of a surface of the cell walls observed by a microscope is defined as Y ?m: X+0.07?Y?X+0.27 ??[1] approximately 0.15?X?approximately 0.35 ??[2].

Abstract: A honeycomb structural body includes at least one honeycomb unit which has a longitudinal direction. The at least one honeycomb unit includes plural cell walls, an inorganic binder, and inorganic particles. The plural cell walls extends along the longitudinal direction from one end face to another end face of the at least one honeycomb unit to define plural cells. The inorganic particles include ceria particles, and a ceramic material which has a degree of self-sintering lower than a degree of self-sintering of the ceria particles.

Abstract: A honeycomb structure includes at least one honeycomb unit having one end face and another end face opposite to the one end face along a longitudinal direction of the at least one honeycomb unit. The at least one honeycomb unit includes an inorganic binder, inorganic particles, cell walls extending along the longitudinal direction from one end face to the another end face to define plural cells, and third material provided on the cell walls. The inorganic particles include first and second materials. The first material includes NOx adsorption material. The second material includes ammonia adsorption material.

Abstract: A honeycomb structure includes a first end face, a second end face, a honeycomb unit, and an ammonia adsorbing material. The second end face is located opposite to the first end face along a longitudinal direction of the honeycomb structure. The honeycomb unit has plural cell walls extending along the longitudinal direction from the first end face to the second end face to define plural cells. The cell walls include a NOx adsorbing material and an inorganic binder. The ammonia adsorbing material is supported on the cell walls. An amount of the ammonia adsorbing material supported on the cell walls is varied between the first end face and the second end face.

Abstract: A honeycomb structure includes adhesive layers and plural honeycomb units bonded to each other by interposing the adhesive layers between the plural honeycomb units. Each of the honeycomb units has partition walls extending along a longitudinal direction of the honeycomb units to define plural through holes. The plural honeycomb units include a SOx absorbent, inorganic particles, and an inorganic binder. An expression Y??0.3X+1.55 (about 1.0?X?about 2.5) is satisfied, in which X represents a content (mol/L) of the SOx absorbent in the partition walls and Y represents a ratio B/A in which A represents a Young's modulus of the honeycomb units and B represents a Young's modulus of the adhesive layers.

Abstract: A honeycomb structure includes at least one honeycomb unit having a first end face and a second end face. The at least one honeycomb unit includes an inorganic binder, inorganic particles, and cell walls extending from the first end face to the second end face to define a plurality of cells. The inorganic particles include ceria particles doped with zirconia. A percentage by weight of zirconia doped in ceria in the ceria particles is in a range of about 20% to about 50%.