The present disclosure relates to roofing granules, such as colored solar-reflective roofing granules, and to methods for making and their use in roofing products. One aspect of the disclosure provides a collection of colored solar-reflective roofing granules, wherein substantially each roofing granule includes an inner layer of a porous ceramic material, the pore size and material of the inner layer being selected such that the inner layer is substantially reflective of infrared radiation; and disposed about and substantially surrounding the inner layer, an outer layer of a substantially colored ceramic material, the outer layer of substantially colored ceramic material being substantially transmissive to infrared radiation, the collection of colored solar-reflective roofing granules having a L* of no more than 60 and a solar reflectivity of at least 30%.

Disclosed are an anti-corrosion and anti-coking ceramic coating with easy state identification for a coal-fired boiler and a preparation method thereof. The ceramic coating is formed by compounding a bottom coating layer and a surface coating layer, wherein the bottom coating layer is prepared from raw materials comprising sodium silicate, lanthanum oxide, niobium pentoxide, aluminum oxide, bismuth oxide, boron oxide, zinc oxide, silicon oxide, titanium dioxide, nano whisker, titanium nitride, and graphite fluoride, and the surface coating layer is prepared from raw materials comprising sodium silicate, lanthanum oxide, niobium pentoxide, chromium oxide, aluminum oxide, bismuth oxide, boron oxide, zinc oxide, silicon oxide, graphite fluoride, titanium nitride, silicon carbide, nano whisker, and cobalt green. An operating state of the ceramic coating is rapidly identified by a color difference between the bottom coating layer and the surface coating layer, which is beneficial to efficient maintenance of the ceramic coating during inspection.

Disclosed are an anti-corrosion and anti-coking ceramic coating with easy state identification for a coal-fired boiler and a preparation method thereof. The ceramic coating is formed by compounding a bottom coating layer and a surface coating layer, wherein the bottom coating layer is prepared from raw materials comprising sodium silicate, lanthanum oxide, niobium pentoxide, aluminum oxide, bismuth oxide, boron oxide, zinc oxide, silicon oxide, titanium dioxide, nano whisker, titanium nitride, and graphite fluoride, and the surface coating layer is prepared from raw materials comprising sodium silicate, lanthanum oxide, niobium pentoxide, chromium oxide, aluminum oxide, bismuth oxide, boron oxide, zinc oxide, silicon oxide, graphite fluoride, titanium nitride, silicon carbide, nano whisker, and cobalt green. An operating state of the ceramic coating is rapidly identified by a color difference between the bottom coating layer and the surface coating layer, which is beneficial to efficient maintenance of the ceramic coating during inspection.

The invention discloses a sound-absorbing material particle and a preparation method thereof. The method for preparing the sound-absorbing material particle comprises: mixing a sound-absorbing raw material with a solvent to form a sound-absorbing slurry; filling the sound-absorbing slurry into a mechanical compression die, and performing compression molding on the sound-absorbing slurry to form a particle; performing a hydrothermal crystallization reaction on the particle to crystallize the sound-absorbing raw material in the particle; and drying the particle to produce the sound-absorbing material particle.

The invention discloses a sound-absorbing material particle and a preparation method thereof. The method for preparing the sound-absorbing material particle comprises: mixing a sound-absorbing raw material with a solvent to form a sound-absorbing slurry; filling the sound-absorbing slurry into a mechanical compression die, and performing compression molding on the sound-absorbing slurry to form a particle; performing a hydrothermal crystallization reaction on the particle to crystallize the sound-absorbing raw material in the particle; and drying the particle to produce the sound-absorbing material particle.

The invention discloses a sound-absorbing material particle and a preparation method thereof. The method for preparing the sound-absorbing material particle comprises: mixing a sound-absorbing raw material with a solvent to form a sound-absorbing slurry; filling the sound-absorbing slurry into a mechanical compression die, and performing compression molding on the sound-absorbing slurry to form a particle; performing a hydrothermal crystallization reaction on the particle to crystallize the sound-absorbing raw material in the particle; and drying the particle to produce the sound-absorbing material particle.

An rear fairing for a pylon supporting an aircraft turbojet engine forms an aerodynamic surface covering the base of the pylon. The rear fairing is elongated in a longitudinal direction and includes a floor arranged opposite the hot gases exiting the turbojet engine and side walls constituting aerodynamic surfaces. The floor and the side walls include ceramic matrix composite materials made from preforms formed by layers of superimposed warp and weft yarns, the preforms have interlayer weaving yarns connecting the layers to one another.

An rear fairing for a pylon supporting an aircraft turbojet engine forms an aerodynamic surface covering the base of the pylon. The rear fairing is elongated in a longitudinal direction and includes a floor arranged opposite the hot gases exiting the turbojet engine and side walls constituting aerodynamic surfaces. The floor and the side walls include ceramic matrix composite materials made from preforms formed by layers of superimposed warp and weft yarns, the preforms have interlayer weaving yarns connecting the layers to one another.

A glass that contains Si, B, Al, and Zn. The glass has SiO.sub.2 at a content of 15% by weight to 65% by weight, B.sub.2O.sub.3 at a content of 11% by weight to 30% by weight, Al.sub.2O.sub.3, and ZnO, wherein a weight ratio of the SiO.sub.2 to the B.sub.2O.sub.3 (SiO.sub.2/B.sub.2O.sub.3) is 1.21 or higher, and a weight ratio of the Al.sub.2O.sub.3 to the ZnO (Al.sub.2O.sub.3/ZnO) is 0.75 to 1.64, and wherein an alkaline-earth metal is excluded as a material contained in the glass.

An object of the present invention is to provide a porous ceramic laminate that can reduce pressure loss of a fluid. The present invention is a porous ceramic laminate comprising a first porous layer and a second porous layer, wherein the second porous layer is laminated on the first porous layer, the second porous layer has a portion being laminated on, in contact with, the first porous layer and a portion being laminated over the first porous layer via air, and a coefficient of variance CV (t.sub.b) of the second porous layer thickness is not larger than 0.35.