The purpose of the present invention is to provide a zirconia-based porous body which can be pulverized in a relatively short time and in which performance deterioration caused by pulverization is suppressed. The present invention pertains to a zirconia-based porous body in which the total pore volume is at least 1.0 ml/g, the pore volume of pores having a diameter of 20-100 nm (exclusive of 100) is at most 0.3 ml/g, and the pore volume of pores having a diameter of 100-1000 nm is at least 0.5 ml/g.

A honeycomb structure includes a honeycomb structure body having porous partition walls, wherein a value of a porosity of the partition wall in a partitioning wall portion between the two cells is defined as a porosity A, a value of a porosity of the partition wall in an intersecting portion that is a region connecting two or more wall portions is defined as a porosity B, a value of A/B obtained by dividing the porosity A by the porosity B is from 0.5 to 0.95, and the porosity A is from 10 to 40%.

Provided are ceramic foams. The ceramic foams may have a hierarchical pore gradient. The ceramic foams may be silica aerogels. The ceramic foams may be made by reaction of one or more precursors in the presence of an inert gas generated by a pore-forming gas-forming additive. The ceramic foams may be used as insulating materials.

A fluid heating component including: a pillar-shaped member made of ceramics and formed with through channels through which a fluid passes, and a conductive coating layer disposed on at least a part of a circumferential surface of the pillar-shaped member, wherein the conductive coating layer is disposed on coats the whole circumference of a cut surface of the pillar-shaped member in a state where the conducive coating layer is electrically connected, in the cut surface of the pillar-shaped member which is perpendicular to a passing direction of the fluid.

A porous ceramic structure includes a porous honeycomb structure composed primarily of cordierite, and Ce- and Zr-containing particles fixedly attached to the honeycomb structure. The Ce- and Zr-containing particles contain Ce and Zr. The Ce- and Zr-containing particles have a fixedly attached portion located inside the honeycomb structure and a protrusion contiguous with the fixedly attached portion and protruding from the honeycomb structure.

Provided is an exhaust gas purifying filter used with a HC purifying catalyst supported thereon. Numerous pores are formed in partitions of the exhaust gas purifying filter. In a cross-section of the partition, pores are open at a passage surface, having an open end of which the opening diameter is 50 μm or larger. In the cross-section of the partitions, the partitions include a narrow part where a pore diameter is 5 μm or more and the pore diameter becomes a minimum in a region. In the cross-section of the partitions, the region is positioned between a pair of virtual lines L.sub.1 and L.sub.2 extending from opposing sides of the opening end to a passage surface positioned opposite to the opening end along the wall thickness direction X, Z. The pore diameter at the narrow part is 6% or more and less than or equal to 20% of the opening diameter.

A method for manufacturing a honeycomb structure, includes: a step of manufacturing a honeycomb formed body to manufacture a non-fired honeycomb formed body, the non-fired honeycomb formed body including a raw material composition containing a ceramic raw material, 0.5 to 5.0 mass % of pore former and water; an induction drying step of drying the manufactured non-fired honeycomb formed body by induction drying to obtain a honeycomb dried body; and a firing step of firing the obtained honeycomb dried body to obtain a honeycomb structure. The induction drying step is to remove 20 to 80% of the entire water that the non-fired honeycomb formed body contained before drying by induction drying to obtain a first dried honeycomb formed body, then turn the first dried honeycomb formed body upside down and remove the residual water by further induction drying to obtain the honeycomb dried body.

A ceramic body exhibiting % P≥50%, df≤0.36, and a combined weight percentage of crystalline phases containing cordierite and indialite of at least 85 wt %, and up to 10 wt % of a crystalline pseudobrookite structured phase, such as armalcolite. The ceramic body contains, as expressed on an oxide basis, either: 1% wt % to 11% wt % titania and 89% wt % to 99% wt % MgO, Al.sub.2O.sub.3, and SiO.sub.2 that have relative weight ratios of MgO:Al.sub.2O.sub.3:SiO.sub.2 within the field defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 13.9:30.7:55.4, and 16.9:30.7:52.4, or 2.5% to 11% titania and 89% wt % to 97.5% wt % MgO, Al.sub.2O.sub.3, and SiO.sub.2 that have relative weight ratios of MgO:Al.sub.2O.sub.3:SiO.sub.2 within the field defined by 15.6:34.0:50.4, 12.6:34.0:53.4, 12.0:35.7:52.3, and 15.0:35.7:49.3. Batch composition mixtures and methods of manufacturing ceramic bodies using the batch compositions are provided, as are other aspects.

A reaction device for reacting a liquid-phase reactant and a gas-phase reactant converted into fine bubbles includes: a porous body that includes a plurality of flow paths and in which the flow paths are separated by porous walls, the porous walls include continuous pores, and the porous body includes a reaction catalyst at least on the surface thereof; a solution supply section for supplying a solution containing a gas-phase reactant and a liquid-phase reactant to the continuous pores in the porous body; and a solution discharge section for discharging solution containing a reaction product obtained when the solution flows through the continuous pores of the porous body.

A honeycomb structure includes a pillar-shaped honeycomb structure body having a porous partition wall so as to surround a plurality of cells extending from a first end face to a second end face, and a circumferential coating layer composed of a circumferential coating material coated on at least a part of circumference of the honeycomb structure body, wherein the circumferential coating layer has a printing area for printing on the surface thereof, the printing area has a lightness (L*) in L*a*b* color space (CIE1976) defined by International Commission on Illumination (CIE) of 35 or more, and the printing area has a surface roughness Ra of 30 μm or less.