The present disclosure provides a method of producing an insulation preform having graded porosity for an exhaust treatment component of a vehicle. The method includes obtaining a first granular insulating material having a first diameter, a second granular insulating material having a second diameter less than the first diameter, an inorganic binder, and water. The method further includes producing a slurry comprising the first granular insulating material, the second granular insulating material, the inorganic binder, and water. The slurry is introduced into a mold having at least one surface adapted for vacuum extraction. A liquid phase of the slurry is evacuated from the mold using vacuum extraction to produce a moist preform. The moist preform has graded porosity such that a greater concentration of the second insulation material is adjacent to the at least one surface than the first insulating material. The moist preform is heated to produce the insulation preform.

The present disclosure provides a method of producing an insulation preform having graded porosity for an exhaust treatment component of a vehicle. The method includes obtaining a first granular insulating material having a first diameter, a second granular insulating material having a second diameter less than the first diameter, an inorganic binder, and water. The method further includes producing a slurry comprising the first granular insulating material, the second granular insulating material, the inorganic binder, and water. The slurry is introduced into a mold having at least one surface adapted for vacuum extraction. A liquid phase of the slurry is evacuated from the mold using vacuum extraction to produce a moist preform. The moist preform has graded porosity such that a greater concentration of the second insulation material is adjacent to the at least one surface than the first insulating material. The moist preform is heated to produce the insulation preform.

A fluorescent member includes: a plurality of fluorescent particles; an inorganic binder; and a plurality of pores. An upper surface of the fluorescent member is a light extraction surface of the fluorescent member. The plurality of pores are localized in a vicinity of at least one of the plurality of fluorescent particles in a cross section that is parallel to the upper surface of the fluorescent member and extends through the fluorescent particles and the pores.

A fluorescent member includes: a plurality of fluorescent particles; an inorganic binder; and a plurality of pores. An upper surface of the fluorescent member is a light extraction surface of the fluorescent member. The plurality of pores are localized in a vicinity of at least one of the plurality of fluorescent particles in a cross section that is parallel to the upper surface of the fluorescent member and extends through the fluorescent particles and the pores.

A method of forming a substrate support for use in a processing chamber includes forming a porous region in each of a plurality of ceramic green sheets, stacking the plurality of ceramic green sheets, each having the porous region formed therein, to form a ceramic laminate, and sintering the ceramic laminate to form a monolithic ceramic body having a porous plug formed therein. The porous plug includes the porous regions in the plurality of ceramic green sheets that are sintered.

A membrane device comprising a porous ceramic member. The porous ceramic member comprises a first support portion operable to support an active layer and further comprises a second support portion. The second support portion has a higher D.sub.75 average pore size than the D.sub.75 average pore size of the first support portion. The second support portion comprises a lattice structure that has a porosity percentage of ?40%. The porous ceramic member has a tensile strength operable to withstand feed application pressure of ?100 kPa (1 bar).

A membrane device comprising a porous ceramic member. The porous ceramic member comprises a first support portion operable to support an active layer and further comprises a second support portion. The second support portion has a higher D.sub.75 average pore size than the D.sub.75 average pore size of the first support portion. The second support portion comprises a lattice structure that has a porosity percentage of ?40%. The porous ceramic member has a tensile strength operable to withstand feed application pressure of ?100 kPa (1 bar).

An optical converter is provided that has both a stable colour even at highest luminous powers and a high luminous efficiency. The optical converter includes a ceramic element that is fluorescent so that light of a first wavelength is absorbed in the ceramic element and fluorescent having longer wavelength light is emitted. The ceramic element includes pores spatially irregularly distributed within the ceramic element. The distribution of the pores within the ceramic element is inhomogeneous so that the radial distribution function of the pore locations deviates from unity and has a maximum at a characteristic distance, the maximum having a value of at least 1.2.

An optical converter is provided that has both a stable colour even at highest luminous powers and a high luminous efficiency. The optical converter includes a ceramic element that is fluorescent so that light of a first wavelength is absorbed in the ceramic element and fluorescent having longer wavelength light is emitted. The ceramic element includes pores spatially irregularly distributed within the ceramic element. The distribution of the pores within the ceramic element is inhomogeneous so that the radial distribution function of the pore locations deviates from unity and has a maximum at a characteristic distance, the maximum having a value of at least 1.2.

A thermally-insulating composite material with co-shrinkage in the form of an insulating material formed by the inclusion of microballoons in a matrix material such that the microballoons and the matrix material exhibit co-shrinkage upon processing. The thermally-insulating composite material can be formed by a variety of microballoon-matrix material combinations such as polymer microballoons in a preceramic matrix material. The matrix materials generally contain fine rigid fillers.