A method of manufacturing a dielectric for a capacitor and a dielectric for a capacitor manufactured thereby are provided. A dielectric for a capacitor is prepared by calcining a precursor mixture containing lead, lanthanum, zirconium, and titanium to produce calcined powder, adding additives including sodium, potassium, and the like to the powder, and sintering the mixture at a low temperature, whereby the dielectric has a high density and a large dielectric constant.

The present disclosure relates to a micromesh proppant for use in hydraulic fracturing of oil and gas wells. In one embodiment, a process for forming proppant particles includes providing a slurry comprising a ceramic raw material containing alumina, atomizing the slurry into droplets, coating seeds comprising alumina with the droplets to form green pellets, sintering the green pellets to form sintered pellets, and breaking the sintered pellets to form proppant particles comprising a sintered ceramic material and having a size of from about 150 mesh to about 500 mesh and a crush strength at 7,500 psi of from about 1% to about 20%. In one embodiment, a proppant particle includes a sintered ceramic material and having a size of from about 150 mesh to about 500 mesh and a crush strength at 7,500 psi of from about 1% to about 20%.

In an aspect, a ferrite composition comprises a Ru—Co.sub.2Z ferrite having the formula: (Ba.sub.3-xM.sub.x)Co.sub.2(M′Ru).sub.yFe.sub.24-2y-zO.sub.41, wherein M is at least one of Sr, Pb, or Ca; M′ is at least one of Co, Zn, Mg, or Cu; x is 1 to 3; y is greater than 0 to 2; and z is −4 to 4. In another aspect, an article comprises the ferrite composition. In yet another aspect, method of making the ferrite composition comprises mixing ferrite precursor compounds comprising Fe, Ba, Co, and Ru; and sintering the ferrite precursor compounds in an oxygen atmosphere to form the Ru—Co.sub.2Z ferrite.

A refractory object may include a zircon body that is intentionally doped with a dopant including an alkaline earth element and aluminum. The refractory object can have an improved creep deformation rate. In an embodiment, the refractory object can have a creep deformation rate of not greater than about 1.8 E-5 h.sup.−1 at a temperature of 1350° C. and a stress of 2 MPa. In another embodiment, the zircon body may include an amorphous phase including an alkaline earth metal element.

A sintered composite ceramic includes a lithium-garnet major phase; and a lithium dendrite growth inhibitor minor phase, such that the lithium dendrite growth inhibitor minor phase comprises lithium tungstate. A method includes sintering a metal oxide component and a garnet component at a temperature in a range of 750° C. to 1500° C. to form a sintered composite ceramic.

A Li.sub.3Mg.sub.2SbO.sub.6-based microwave dielectric ceramic material easy to sinter and with high Q value, and a preparation method thereof are disclosed. A chemical formula of the material is Li.sub.3(Mg.sub.1-xZn.sub.x).sub.2SbO.sub.6, wherein 0.02≤x≤0.08. The preparation method includes: 1) mixing and ball-milling Sb.sub.2O.sub.3 and Li.sub.2CO.sub.3 according to a chemical ratio and then drying, and conducting pre-sintering to obtain a Li.sub.3SbO.sub.4 phase; and 2) mixing and ball-milling MgO, ZnO and Li.sub.3SbO.sub.4 powder according a chemical ratio of Li.sub.3(Mg.sub.1-xZn.sub.x).sub.2SbO.sub.6 and then drying, conducting granulation and sieving after adding an adhesive, pressing into a cylindrical body, and sintering the cylindrical body into ceramic in the air at 1325° C. and under normal pressure, wherein a dielectric constant is 7.2-8.5, a quality factor is 51844-97719 GHz, and a temperature coefficient of resonance frequency is −14-1 ppm/° C.

A gas turbine engine article includes a substrate and a silicate-resistant barrier coating disposed on the substrate. The silicate-resistant barrier coating has an engineered microstructure that includes a refractory matrix formed of grains and calcium aluminosilicate additive (CAS additive) dispersed in grain boundaries between the grains.

A wafer boat according to the present disclosure includes a plurality of support columns, each having a pillar shape and comprising a plurality of grooves configured to have a wafer placed thereon, and support plates configured to support both end portions of the plurality of support columns, respectively. Each of the plurality of support columns are formed of a ceramic containing aluminum oxide or silicon carbide as a main constituent, and an outer side surface of the plurality of support columns is a ground surface and/or a polished surface.

Disclosed is a method for recycling a coal liquefaction residue. The method includes S1, drying a coal liquefaction residue and pulverizing to obtain a pulverized coal liquefaction residue; S2, subjecting the pulverized coal liquefaction residue to a solvothermal extraction in an autoclave to obtain an extract liquid and a residue; S3, distilling the extract liquid and recovering an organic solvent to obtain a solid extract.

An yttrium oxide-based sintered body contains yttrium oxide as a main constituent and 0.1 wt % or more and 5.0 wt % or less of zirconium on a ZrO.sub.2 basis. Such an yttrium oxide-based sintered body made with yttrium oxide and a certain amount of zirconium oxide therein is highly resistant to corrosive chemicals while maintaining superior resistance to plasma and corrosive gases.