Provided is a novel compound which can be used for positive-electrode catalysts of metal-air batteries. The melilite-type complex oxide according to the present invention is represented by a general formula (BazSr1z)2CoxFe22x(SiyGe1y)1+xO7 (in the formula, 0x1, 0y1, and 0z1, excluding the case where x=1, y=1, and z=0, the case where x=1, y=1, and z=1, the case where x=1, y=0, and z=0, the case where x=1, =0, and z=1, the case where x=0, y=0, and z=0, and the case where x=0, y=0, and z=1).

The present invention relates to a boroaluminosilicate mineral material, a low temperature co-fired ceramic composite material, a low temperature co-fired ceramic, a composite substrate and preparation methods thereof. A boroaluminosilicate mineral material for a low temperature co-fired ceramic, the boroaluminosilicate mineral material comprises the following components expressed in mass percentages of the following oxides: 0.41%-1.15% of Na2O, 14.15%-23.67% of K2O, 1.17%-4.10% of CaO, 0-2.56% of Al2O3, 13.19%-20.00% of B.sub.2O.sub.3, and 53.47%-67.17% of SiO.sub.2. The aforementioned boroaluminosilicate mineral material is chemically stable; a low temperature co-fired ceramic prepared from it not only has excellent dielectric properties, but also has a low sintering temperature, a low thermal expansion coefficient, and high insulation resistance; it is also well-matched with the LTCC process and can be widely used in the field of LTCC package substrates.

The present invention relates to a boroaluminosilicate mineral material, a low temperature co-fired ceramic composite material, a low temperature co-fired ceramic, a composite substrate and preparation methods thereof. A boroaluminosilicate mineral material for a low temperature co-fired ceramic, the boroaluminosilicate mineral material comprises the following components expressed in mass percentages of the following oxides: 0.41%-1.15% of Na2O, 14.15%-23.67% of K2O, 1.17%-4.10% of CaO, 0-2.56% of Al2O3, 13.19%-20.00% of B.sub.2O.sub.3, and 53.47%-67.17% of SiO.sub.2. The aforementioned boroaluminosilicate mineral material is chemically stable; a low temperature co-fired ceramic prepared from it not only has excellent dielectric properties, but also has a low sintering temperature, a low thermal expansion coefficient, and high insulation resistance; it is also well-matched with the LTCC process and can be widely used in the field of LTCC package substrates.

Garnet silicate is garnet silicate containing, as a main component, silicate represented by a general formula: Lu.sub.2CaMg.sub.2(SiO.sub.4).sub.3. The garnet silicate includes primary particles having a particle shape derived from a crystal structure of garnet. Moreover, the garnet silicate further contains alkaline metal including at least lithium, in which a content of the alkaline metal is less than 2000 ppm. The garnet silicate phosphor includes garnet silicate and ions which are included in the garnet silicate and function as a light emission center. The wavelength converter includes the garnet silicate phosphor. A light emitting device includes the garnet silicate phosphor or the wavelength converter.

Garnet silicate is garnet silicate containing, as a main component, silicate represented by a general formula: Lu.sub.2CaMg.sub.2(SiO.sub.4).sub.3. The garnet silicate includes primary particles having a particle shape derived from a crystal structure of garnet. Moreover, the garnet silicate further contains alkaline metal including at least lithium, in which a content of the alkaline metal is less than 2000 ppm. The garnet silicate phosphor includes garnet silicate and ions which are included in the garnet silicate and function as a light emission center. The wavelength converter includes the garnet silicate phosphor. A light emitting device includes the garnet silicate phosphor or the wavelength converter.

The object of the present invention is to provide a needle coke for a graphite electrode, which suppresses puffing of the needle coke and improves the production yield and performances of graphite electrodes without incurring a large cost in the production of a needle coke, and also provide a production method and an inhibitor therefor. An inhibitor for graphite electrode production, including at least one of a metal consisting of an element (M) and an oxide comprising the element (M), wherein the element (M) is at least one element selected from the group consisting of group 4 elements, group 8 elements, group 9 elements, group 10 elements, group 13 elements, group 14 elements and group 15 elements of the long-form periodic table, or including at least one of the metal consisting of an element (M) and a compound including the element (M), wherein the inhibitor volatilizes at a temperature of 2100 to 6000 C.

The object of the present invention is to provide a needle coke for a graphite electrode, which suppresses puffing of the needle coke and improves the production yield and performances of graphite electrodes without incurring a large cost in the production of a needle coke, and also provide a production method and an inhibitor therefor. An inhibitor for graphite electrode production, including at least one of a metal consisting of an element (M) and an oxide comprising the element (M), wherein the element (M) is at least one element selected from the group consisting of group 4 elements, group 8 elements, group 9 elements, group 10 elements, group 13 elements, group 14 elements and group 15 elements of the long-form periodic table, or including at least one of the metal consisting of an element (M) and a compound including the element (M), wherein the inhibitor volatilizes at a temperature of 2100 to 6000 C.

A composition comprising synthetic mineral particles, such as silicate or phyllosilicate mineral particles, is presented. The composition can be prepared by a process in which a hydrogel precursor of the synthetic mineral particles is produced by a coprecipitation reaction between at least one compound comprising silicon, such as sodium metasilicate, and at least one compound comprising at least one metal element, such as a dicarboxylate salt of the formula M(R.sub.1COO).sub.2, wherein R.sub.1 is H or an alkyl group having 1 to 4 carbon atoms. The coprecipitation reaction also takes place in the presence of at least one carboxylate salt of formula R.sub.2COOM wherein M is Na or K, and R.sub.2 is H or an alkyl group having 1 to 4 carbon atoms.

A composition comprising synthetic mineral particles, such as silicate or phyllosilicate mineral particles, is presented. The composition can be prepared by a process in which a hydrogel precursor of the synthetic mineral particles is produced by a coprecipitation reaction between at least one compound comprising silicon, such as sodium metasilicate, and at least one compound comprising at least one metal element, such as a dicarboxylate salt of the formula M(R.sub.1COO).sub.2, wherein R.sub.1 is H or an alkyl group having 1 to 4 carbon atoms. The coprecipitation reaction also takes place in the presence of at least one carboxylate salt of formula R.sub.2COOM wherein M is Na or K, and R.sub.2 is H or an alkyl group having 1 to 4 carbon atoms.

Provided is a method of preparing a metal oxide-silica composite aerogel and a metal oxide-silica composite aerogel having an excellent weight reduction property prepared by the method. The method comprises adding an acid catalyst to a first water glass solution to prepare an acidic water glass solution (step 1); adding a metal ion solution to the acidic water glass solution to prepare a precursor solution (step 2); and adding a second water glass solution to the precursor solution and performing a gelation reaction (step 3).