An infrared selective radiation cooling nano-functional composition and a preparation method thereof, wherein the composition is prepared from silica, a rare earth silicate compound and a molybdate compound according to a mass ratio of 1:(0.5-2):(0.5-2) by ball milling and uniform mixing, and the silica, the rare earth silicate compound and the molybdate compound have high infrared selective radiation performance at 8-10 μm, 9-12 μm and 10-14 μm. The rare earth silicate and molybdate compound are prepared by a sol-gel and a high-temperature solid phase process according to stoichiometric ratios SiO.sub.2-(0.5-2)Re.sub.2O.sub.3-(0.1-1.0)Na.sub.2O (Re═La, Sm, Eu, Gd, Tb, Dy, Er, Tm, Yb, Y or Sc) and RMoO.sub.4 (R═Mg, Ca, Sr or Ba). The infrared selective radiation cooling nano-functional composition prepares functional devices such as day and night double-effect radiation coolers to provide zero-energy cooling, energy saving and efficiency improvement functions for buildings, grain and oil stores, solar battery back plates and the like.

An infrared selective radiation cooling nano-functional composition and a preparation method thereof, wherein the composition is prepared from silica, a rare earth silicate compound and a molybdate compound according to a mass ratio of 1:(0.5-2):(0.5-2) by ball milling and uniform mixing, and the silica, the rare earth silicate compound and the molybdate compound have high infrared selective radiation performance at 8-10 μm, 9-12 μm and 10-14 μm. The rare earth silicate and molybdate compound are prepared by a sol-gel and a high-temperature solid phase process according to stoichiometric ratios SiO.sub.2-(0.5-2)Re.sub.2O.sub.3-(0.1-1.0)Na.sub.2O (Re═La, Sm, Eu, Gd, Tb, Dy, Er, Tm, Yb, Y or Sc) and RMoO.sub.4 (R═Mg, Ca, Sr or Ba). The infrared selective radiation cooling nano-functional composition prepares functional devices such as day and night double-effect radiation coolers to provide zero-energy cooling, energy saving and efficiency improvement functions for buildings, grain and oil stores, solar battery back plates and the like.

A modification layer on a surface of a ceramic substrate, includes, in parts by mass: 56 to 67.5 parts of silicon dioxide; 12 to 18 parts of aluminum oxide; and 2.8 to 5.5 parts of lithium oxide. In an embodiment, the modification layer further includes, in parts by mass: at least one of 1.8 to 2.8 parts of phosphorus pentoxide; 0.5 to 2.0 parts of calcium oxide; 0.15 to 1.5 parts of magnesium oxide; and 2.5 to 5.25 parts of barium oxide.

In additive manufacturing operations, powders used in stereolithographic processes need to be precisely spread out in a uniform fashion at every pass of the stereolithographic process to ensure predictability in powder surface morphology. Typically, this is difficult to achieve with conventional powders because often these powders suffer from poor flowability, which may further deteriorate over time, and impairs the efficiency of the stereolithographic processes. The present disclosure describes additive manufacturing powders having improved physical characteristics such as flowability and tap density, which are less sensitive or insensitive to ambient humidity. For example, there is described a powder that includes spherical particles having a particle size distribution of less than 1000 micrometers and having a measurable flowability as determined in accordance with ASTM B213 at 75% relative humidity.

A filter including a porous support defining one or more channels therethrough, and a porous ceramic membrane layer on a surface of the porous support defining at least one of the one or more channels. The ceramic membrane layer includes an inorganic ceramic composition having the formula SiM.sup.p.sub.xpC.sub.yN.sub.zO.sub.mH.sub.n, where each M.sup.p present is independently selected from a p-block element or a d-block element; p is an integer from 1 to 5; for each M.sup.p present, xp is independently from about 0 to about 60; y is from about 0 to about 60; z is from about 0 to about 60; m is from about 0 to about 40; and n is zero or nonzero. At least one of y and z is nonzero when p is zero, and p is nonzero when y and z are both zero.

A filter including a porous support defining one or more channels therethrough, and a porous ceramic membrane layer on a surface of the porous support defining at least one of the one or more channels. The ceramic membrane layer includes an inorganic ceramic composition having the formula SiM.sup.p.sub.xpC.sub.yN.sub.zO.sub.mH.sub.n, where each M.sup.p present is independently selected from a p-block element or a d-block element; p is an integer from 1 to 5; for each M.sup.p present, xp is independently from about 0 to about 60; y is from about 0 to about 60; z is from about 0 to about 60; m is from about 0 to about 40; and n is zero or nonzero. At least one of y and z is nonzero when p is zero, and p is nonzero when y and z are both zero.

A glass powder of the present invention is a glass powder, which is formed of alkali borosilicate glass, wherein the glass powder includes 0.1 mol % to 1.0 mol %, provided that 1.0 mol % is excluded, of Li.sub.2O+Na.sub.2O+K.sub.2O in a glass composition, has a molar ratio Li.sub.2O/(Li.sub.2O+Na.sub.2O+K.sub.2O) of from 0.35 to 0.65, a molar ratio Na.sub.2O/(Li.sub.2O+Na.sub.2O+K.sub.2O) of from 0.25 to 0.55, and a molar ratio K.sub.2O/(Li.sub.2O+Na.sub.2O+K.sub.2O) of from 0.025 to 0.20, and has a specific dielectric constant at 25° C. and 16 GHz of from 3.5 to 4.0 and a dielectric dissipation factor at 25° C. and 16 GHz of 0.0020 or less.

A ceramic circuit board includes: a ceramic board; and an internal conductor disposed in the ceramic board, in which the ceramic board contains glass, a willemite filler, and an alumina filler, and an average particle diameter of the willemite filler is larger than an average particle diameter of the alumina filler.

The present invention refers to a stable sodium and iron silicate solution that has a weight ratio of SiO.sub.2 to Na.sub.2O from 1.5 to 2.5 and a total percentage of solids, expressed by the sum of SiO.sub.2 and Na.sub.2O, from 20% to 55%. Said solution also has a soluble iron content, expressed by Fe, from 0.1% to 7%, and a water content from 38% to 79.9%. The present invention also refers to the process for preparing said stable solution of sodium and iron silicate, which comprises the steps of: (a) providing a siliceous material containing iron; (b) submitting said siliceous material containing iron to a hydrothermal treatment with caustic soda under high temperature and controlled pressure; and (c) filtering said reacted solution to separate the reacted portion of the hydrothermal treatment from the unreacted portion. Additionally, the present invention refers to the uses of said stable sodium and iron silicate solution.

Thermal storage unit including: a receptacle including orifices allowing a heat-transfer fluid to be introduced into and extracted, and a stack of bricks, arranged in the receptacle in superposed strata, each stratum having lower and upper large faces and defining a plurality of ducts opening via lower and upper openings, the stack including a pair of strata of a lower and upper stratum, the upper and lower large faces of the lower and upper stratum being separated to define a passage, placing an upper opening of a lower duct of the lower stratum in fluidic communication with at least one lower opening, entirely offset with respect to the upper opening, of at least one upper duct of the upper stratum, the lower large face of the upper stratum closing off, at least partially, the upper opening, when the upper opening is observed, along its axis, from the lower duct.