The present invention discloses a method for uniformly coating metal nanoparticles without a carbon impurity on an oxide ceramic powder surface, which includes the steps of putting grinded and mixed a metal organic material and oxide ceramic powder into a rotational reaction chamber, then bubbling oxidizing gas under a rotational and heating condition to oxidize the metal organic material into a metal oxide, and finally bubbling reducing gas to reduce the metal oxide into nanoparticles in a metallic state, so as to implement the uniform coating of the nanoparticles in the metallic state, and avoid coarsening and growing problems of nanoparticles led by a long-term coating reaction under a high temperature. The present invention has a simple method and a short preparation period, and the metal nanoparticles prepared are uniformly dispersed and have wide application prospects in multiple fields like catalytic materials and conductive ceramics.

Process for preparing a porous monolith comprising between 10% and 100% by weight of a semiconductor relative to the total weight of the porous monolith, which process comprises the following steps: a) a first aqueous suspension containing polymer particles is prepared; b) a second aqueous suspension containing particles of least one inorganic semiconductor is prepared; c) the two aqueous suspensions prepared in steps a) and b) are mixed in order to obtain a paste; d) a heat treatment of the paste obtained in step c) is carried out in order to obtain the monolith with multimodal porosity.

In one embodiment, a method includes forming a powder having a composition with the formula: A.sub.hB.sub.iC.sub.jO.sub.12, where h is 3±l 0%, i is 2=10%, j is 3±10%, A includes one or more rare earth elements, B includes aluminum and/or gallium, and C includes aluminum and/or gallium. The method additionally includes consolidating the powder to form an optically transparent ceramic, and applying at least one thermodynamic process condition during the consolidating to reduce oxygen and/or thermodynamically reversible defects in the ceramic. In another embodiment, a scintillator includes (Gd.sub.3-a-cY.sub.a)x(Ga.sub.5-bAl.sub.b).sub.yO.sub.12D.sub.c, where a is from about 0.05-2, b is from about 1-3, x is from about 2.8-3.2, y is from about 4.8-5.2, c is from about 0.003-0.3, and D is a dopant, and where the scintillator is an optically transparent ceramic scintillator having physical characteristics of being formed from a ceramic powder consolidated in oxidizing atmospheres.

A sintered MnZn ferrite body containing main components comprising 53.30-53.80% by mol of Fe calculated as Fe.sub.2O.sub.3, 6.90-9.50% by mol Zn calculated as ZnO, and the balance of Mn calculated as MnO, and sub-components comprising 0.003-0.020 parts by mass of Si calculated as SiO.sub.2, more than 0 parts and 0.35 parts or less by mass of Ca calculated as CaCO.sub.3, 0.30-0.50 parts by mass of Co calculated as Co.sub.3O.sub.4, 0.03-0.10 parts by mass of Zr calculated as ZrO.sub.2, and 0-0.05 parts by mass of Ta calculated as Ta.sub.2O.sub.5, pre 100 parts by mass in total of the main components (calculated as the oxides), and having an average crystal grain size of 3 μm or more and less than 8 μm and a density of 4.65 g/cm.sup.3 or more.

One aspect relates to a process for producing a sintered workpiece, which includes sintering of a ceramic material at a temperature of at least 1000° C. and in an atmosphere, in the case of which the partial pressure of atmospheric air is reduced to less than 10.sup.−6-times, based on the ambient air at the same temperature under equilibrium conditions.

A transparent complex oxide sintered body is manufactured by sintering a compact in an inert atmosphere or vacuum, and HIP treating the sintered compact, provided that the compact is molded from a source powder based on a rare earth oxide: (Tb.sub.xY.sub.1-x).sub.2O.sub.3 wherein 0.4≤x≤0.6, and the compact, when heated in air from room temperature at a heating rate of 15° C./min, exhibits a weight gain of at least y % due to oxidative reaction, y being determined by the formula: y=2x+0.3. The sintered body has a long luminescent lifetime as a result of controlling the valence of Tb ion.

A composite magnetic material has a plurality of grains having a magnetic ferrite phase, grain boundaries surrounding the grains, and a plurality of nanoparticles disposed at the grain boundaries. The nanoparticles of the composite material are both magnetic and electrically insulating, having a magnetic flux density of greater than about 100 mT and an electrical resistivity of at least about 10.sup.8 Ohm-cm. Also provided is a method of making the composite material. The material is useful for making inductor cores of electronic devices.

A piezoelectric material which is low in load on the environment, and also satisfies both the requirements of a high piezoelectric constant and a high mechanical quality factor. The piezoelectric material comprises a plurality of crystal grains containing Ba, Ca, Ti, Zr, Mn, and O. An average equivalent circle diameter of the crystal grains is not smaller than 1.0 μm and not larger than 10 μm. The crystal grains include crystal grains A each having a first domain with a width of not smaller than 300 nm and not larger than 800 nm, and crystal grains B each having a second domain with a width of not smaller than 20 nm and not larger than 50 nm.

A ceramic matrix composite manufacturing method includes: forming a zirconia-sol containing layer that contains zirconia sol, on fabric having an interface layer formed on a periphery of each of a plurality of ceramic-made fibers; impregnating the fabric having the zirconia-sol containing layer formed, with a polymer as a precursor, to form a body; supplying oxygen to the polymer included in the body; heating the body in an inert gas atmosphere to cause a reaction of the polymer to form a matrix; and heating the body in an oxygen atmosphere to remove the interface layer, after supplying the oxygen and heating the body in the inert gas atmosphere, to generate a ceramic matrix composite in which the matrix is interposed between the fibers.

Disclosed are a dielectric ceramic includes a plurality of crystal grain bulks including a ceramic, and a grain boundary between the plurality of crystal grain bulks, wherein a dopant is segregated in the grain boundary.