A method of forming a composite article may include impregnating an inorganic fiber porous preform with a first slurry composition. The slurry composition includes particles, a solvent, and a pre-gellant material. Gelling of the pre-gellant material in the slurry composition is initiated to substantially immobilize the particles and yield a gelled article. The method also includes impregnating the gelled article with a second solution that includes a high char-yielding component, and pyrolyzing the high char-yielding component to yield carbon and form a green composite article. The green composite article is then infiltrated with a molten metal or alloy infiltrant to form the composite article. The molten infiltrant reacts with carbon, and the final composite article may include less residual metal or alloy than a composite article formed without using the second solution.

Proppant particles formed from slurry droplets and methods of use are disclosed herein. The proppant particles can include a sintered ceramic material and can have a size of about 80 mesh to about 10 mesh and an average largest pore size of less than about 20 microns. The methods of use can include injecting a hydraulic fluid into a subterranean formation at a rate and pressure sufficient to open a fracture therein and injecting a fluid containing a proppant particle into the fracture, the proppant particle including a sintered ceramic material, a size of about 80 mesh to about 10 mesh, and an average largest pore size of less than about 20 microns.

A method of forming a composite article may include impregnating an inorganic fiber porous preform with a first slurry composition. The slurry composition includes particles, a solvent, and a pre-gellant material. Gelling of the pre-gellant material in the slurry composition is initiated to substantially immobilize the particles and yield a gelled article. The method also includes impregnating the gelled article with a second solution that includes a high char-yielding component, and pyrolyzing the high char-yielding component to yield carbon and form a green composite article. The green composite article is then infiltrated with a molten metal or alloy infiltrant to form the composite article. The molten infiltrant reacts with carbon, and the final composite article may include less residual metal or alloy than a composite article formed without using the second solution.

In the field of refining metal melts or slags there is disclosed in particular a reactive material based on calcium aluminate and carbon, its process of preparation and various methods for refining metal melts using the same.

Proppant particles formed from slurry droplets and methods of use are disclosed herein. The proppant particles can include a sintered ceramic material and can have a size of about 80 mesh to about 10 mesh and an average largest pore size of less than about 20 microns. The methods of use can include injecting a hydraulic fluid into a subterranean formation at a rate and pressure sufficient to open a fracture therein and injecting a fluid containing a proppant particle into the fracture, the proppant particle including a sintered ceramic material, a size of about 80 mesh to about 10 mesh, and an average largest pore size of less than about 20 microns.

Ceramic particles for use in a solar power tower and methods for making and using the ceramic particles are disclosed. The ceramic particle can include a sintered ceramic material formed from a mixture of a ceramic raw material and a darkening component comprising MnO as Mn.sup.2+. The ceramic particle can have a size from about 8 mesh to about 170 mesh and a density of less than 4 g/cc.

Methods include providing an aqueous slurry of ceramic forming raw materials, where at least a portion of the ceramic forming raw materials are enhanced particulates, and flowing the slurry through at least one extrusion die face to form slurry bodies while the slurry is under a hypotensive condition which is less than about 30 kPa, or otherwise pressure lower than conventional extrusion pressures using unenhanced raw materials. The slurry bodies may then be received in a collecting hopper, and thereafter sintering to form particles, such as ceramic proppant particles. Enhanced particulates may be raw material particulates that are coated, selectively shaped, of particular size(s), or any combination thereof.

Dental restorations are created by preparing a hydrocolloid mold for such dental appliances as crowns and bridges. A slurry of zirconia powder and 3-O-acryloyl-D-glucose is prepared. The slurry is gelcast in the hydrocolloid mold with polymerization of the 3-O-acryloyl-D-glucose to a green body. The green body is dried and machined to the form of the dental restoration. The polymerized 3-O-acryloyl-D-glucose is then burned from the machined green body. The remaining zirconia body in the form of the dental restoration is then sintered to form the finished device.

A cellulose nanocrystal-modified ceramic blank and a preparation method thereof are disclosed. Cellulose nanocrystals are added into a ceramic blank in gelcasting. The cellulose nanocrystal-modified ceramic blank comprises, by weight, 0.1 to 10 parts of cellulose nanocrystals, 0.1 to 30 parts of organic gel and 70 to 99 parts of ceramic powder. The cellulose nanocrystal has length of 100 to 300 nm, a diameter of 10 to 20 nm, a slenderness ratio of 10 to 15 , and an elastic modulus of 100 to 150 GPa. The drying strength of the ceramic blank with the cellulose nanocrystals is obviously improved.

A piezoelectric/electrostrictive material is composed of Mn and a compound of Pb(Zn, Nb)O.sub.3Pb(Ni, Nb)O.sub.3Pb(Zr, Ti)O.sub.3. A ratio of a molar amount of Mn relative to a sum of respective molar amounts of Ni, Zn, Ti, Zr, Nb and Mn is at least 0.001 to no more than 0.015. A ratio of a molar amount of Nb relative to a sum of respective molar amounts of Ni and Zn is at least 2.007 to no more than 2.125.