Abstract: Fine, highly-crystallized metal powder is produced at low cost and high efficiency by a method involving: ejecting raw material powder composed of one or more kinds of thermally decomposable metal compound powders into a reaction vessel through a nozzle together with a carrier gas and producing a metal powder by heating the raw material powder at a temperature T2 which is higher than the decomposition temperature of the raw material powder and not lower than (Tm?200°) C. where Tm is the melting point (° C.) of the metal to be produced, while allowing the raw material powder to pass through the reaction vessel in a state where the raw material powder is dispersed in a gas phase at a concentration of 10 g/liter or less, wherein an ambient temperature T1 of a nozzle opening part is set to a temperature of 400° C. or higher and lower than (Tm?200°) C.

Abstract: There is provided a catalyst for hydrocarbon reforming having a high deposition suppressing effect with respect to a carbonaceous material on the catalyst surface even in a case where a reforming material including carbon dioxide, in particular, formed of only carbon dioxide is used in a reforming reaction, a method of manufacturing the same, and a method of manufacturing a synthesis gas using the catalyst.

Abstract: A nickel powder with an average particle size of 0.05 to 1.0 ?m, which is composed of nickel particles having an oxidized surface layer and containing sulfur, wherein the sulfur content with respect to the total weight of the powder is 100 to 2000 ppm, and the intensity of a peak identified to sulfur bonded to nickel in surface analysis by ESCA of the nickel particles varies in a direction toward the center from the surface of the particles, and this intensity has its maximum at a location deeper than 3 nm from the particle outermost surface. This nickel powder is manufactured by bringing a nickel powder containing sulfur and dispersed in a non-oxidizing gas atmosphere into contact with an oxidizing gas at a high temperature.

Abstract: Fine, highly-crystallized metal powder is produced at low cost and high efficiency by a method involving: ejecting raw material powder composed of one or more kinds of thermally decomposable metal compound powders into a reaction vessel through a nozzle together with a carrier gas and producing a metal powder by heating the raw material powder at a temperature T2 which is higher than the decomposition temperature of the raw material powder and not lower than (Tm?200)° C. where Tm is the melting point (° C.) of the metal to be produced, while allowing the raw material powder to pass through the reaction vessel in a state where the raw material powder is dispersed in a gas phase at a concentration of 10 g/liter or less, wherein an ambient temperature T1 of a nozzle opening part is set to a temperature of 400° C. or higher and lower than (Tm?200)° C.

Abstract: A nickel powder with an average particle size of 0.05 to 1.0 ?m, which is composed of nickel particles having an oxidized surface layer and containing sulfur, wherein the sulfur content with respect to the total weight of the powder is 100 to 2000 ppm, and the intensity of a peak identified to sulfur bonded to nickel in surface analysis by ESCA of the nickel particles varies in a direction toward the center from the surface of the particles, and this intensity has its maximum at a location deeper than 3 nm from the particle outermost surface. This nickel powder is manufactured by bringing a nickel powder containing sulfur and dispersed in a non-oxidizing gas atmosphere into contact with an oxidizing gas at a high temperature.

Abstract: A nickel powder with an average particle size of 0.05 to 1.0 ?m, which is composed of nickel particles having an oxidized surface layer and containing sulfur, wherein the sulfur content with respect to the total weight of the powder is 100 to 2000 ppm, and the intensity of a peak identified to sulfur bonded to nickel in surface analysis by ESCA of the nickel particles varies in a direction toward the center from the surface of the particles, and this intensity has its maximum at a location deeper than 3 nm from the particle outermost surface. This nickel powder is manufactured by bringing a nickel powder containing sulfur and dispersed in a non-oxidizing gas atmosphere into contact with an oxidizing gas at a high temperature.

Abstract: The invention provides a nickel-rhenium alloy powder that contains nickel as a main component, 0.1 to 10% by weight of rhenium and 50 to 10,000 ppm of silicon in terms of silicon atoms, and that is suitable, in particular, for the formation of an internal electrode layer for a multilayer ceramic electronic component. The obtained powder is homogeneously mixed and dispersed in an organic vehicle, together with other additives as needed, to prepare a conductor paste. When used in particular for forming an internal electrode of a multilayer ceramic electronic component, the nickel-rhenium alloy powder of the invention delays sintering initiation and slows down the progress of sintering during firing, even for extremely fine powders, while bringing the sintering shrinkage behaviors of electrode layers and ceramic layers closer to each other. Moreover, there occurs no electrode spheroidizing caused by oversintering. A thinner, dense internal electrode having excellent continuity can be formed as a result.

Abstract: A nickel-rhenium alloy powder comprising nickel as a main component, 0.1 to 10% by weight of rhenium, and having an average particle size of 0.05 to 1.0 ?m is provided. The nickel-rhenium alloy powder has a surface oxide film containing a nickel oxide and a rhenium oxide, and the amount of oxygen in the surface oxide film is 0.1 to 3.0% by weight relative to the total weight of the powder. The nickel-rhenium alloy powder is suitable, in particular, for forming internal electrode layers of a multilayer ceramic electronic component. The obtained powder is homogeneously mixed and dispersed in an organic vehicle, together with other additives as needed, to prepare a conductor paste. The surface oxide film allows bringing the sintering shrinkage behavior of electrode layers and ceramic layers closer to each other when the nickel-rhenium alloy powder is used, in particular, for forming internal electrodes of a multilayer ceramic electronic component.

Abstract: A melt of nickel nitrate hydrate is introduced as droplets or liquid flow into a heated reaction vessel and thermally decomposed in a gas phase at a temperature of 1200° C. or more and at an oxygen partial pressure equal to or below the equilibrium oxygen pressure of nickel-nickel oxide at that temperature to manufacture a highly crystalline fine nickel powder with an extremely narrow particle size distribution. The oxygen partial pressure during the thermal decomposition is preferably 10?2 Pa or less, and a metal other than nickel, a semimetal and/or a compound of these may be added to the nickel nitrate hydrate melt to manufacture a highly crystalline nickel alloy powder or highly crystalline nickel composite powder. The resultant powder is suited in particular to thick film pastes such as conductor pastes for manufacturing ceramic multilayer electronic components.

Abstract: A nickel-rhenium alloy powder comprising nickel as a main component, 0.1 to 10% by weight of rhenium, and having an average particle size of 0.05 to 1.0 ?m is provided. The nickel-rhenium alloy powder has a surface oxide film containing a nickel oxide and a rhenium oxide, and the amount of oxygen in the surface oxide film is 0.1 to 3.0% by weight relative to the total weight of the powder. The nickel-rhenium alloy powder is suitable, in particular, for forming internal electrode layers of a multilayer ceramic electronic component. The obtained powder is homogeneously mixed and dispersed in an organic vehicle, together with other additives as needed, to prepare a conductor paste. The surface oxide film allows bringing the sintering shrinkage behavior of electrode layers and ceramic layers closer to each other when the nickel-rhenium alloy powder is used, in particular, for forming internal electrodes of a multilayer ceramic electronic component.

Abstract: The invention provides a nickel-rhenium alloy powder that comprises nickel as a main component, 0.1 to 10% by weight of rhenium and 50 to 10,000 ppm of silicon in terms of silicon atoms, and that is suitable, in particular, for the formation of an internal electrode layer for a multilayer ceramic electronic component. The obtained powder is homogeneously mixed and dispersed in an organic vehicle, together with other additives as needed, to prepare a conductor paste. When used in particular for forming an internal electrode of a multilayer ceramic electronic component, the nickel-rhenium alloy powder of the invention delays sintering initiation and slows down sintering progress during firing, even for extremely fine powders, while bringing the sintering shrinkage behaviors of electrode layers and ceramic layers closer to each other. Moreover, there occurs no electrode spheroidizing caused by oversintering. A thinner, dense internal electrode having excellent continuity can be formed as a result.

Abstract: A nickel powder with a mean particle size of 0.05 to 1.0 ?m, the nickel powder having a thin oxidized layer of nickel on a surface thereof, an oxygen content of 0.3 to 3.0 wt. % and a carbon content of 100 ppm or less per specific surface area of 1 m2/g of the powder, in a weight proportion of carbon to the nickel powder of unit weight. When the powder is used for a conductive paste for forming inner electrode layers of a multilayer electronic component, it enables a decrease in the residual carbon amount after a binder removal process, thereby making it possible to obtain a multilayer ceramic electronic component excellent electrical characteristics and high reliability in which electrode layers excelling in continuity are formed without decreasing the strength and electrical characteristics of the electronic component or creating structural defects.

Abstract: Metal particles that can be alloyed with rhenium are dispersed as a main component in a gas phase, a rhenium oxide vapor is made to be present around these particles, the rhenium oxide is reduced, and the rhenium precipitated on the surface of the main component metal particles as a result of this reduction is diffused under a high temperature into the main component metal particles, which gives a rhenium-containing alloy powder including the main component metal and rhenium. The powder thus obtained preferably contains 0.01 to 50 wt % rhenium, has an average particle size of 0.01 to 10 ?m, and is made into a conductor paste by being uniformly mixed and dispersed in an organic vehicle along with other additives as needed.

Abstract: A nickel powder with an average particle size of 0.05 to 1.0 ?m, which is composed of nickel particles having an oxidized surface layer and containing sulfur, wherein the sulfur content with respect to the total weight of the powder is 100 to 2000 ppm, and the intensity of a peak identified to sulfur bonded to nickel in surface analysis by ESCA of the nickel particles varies in a direction toward the center from the surface of the particles, and this intensity has its maximum at a location deeper than 3 nm from the particle outermost surface. This nickel powder is manufactured by bringing a nickel powder containing sulfur and dispersed in a non-oxidizing gas atmosphere into contact with an oxidizing gas at a high temperature.

Abstract: A melt of nickel nitrate hydrate is introduced as droplets or liquid flow into a heated reaction vessel and thermally decomposed in a gas phase at a temperature of 1200° C. or more and at an oxygen partial pressure equal to or below the equilibrium oxygen pressure of nickel-nickel oxide at that temperature to manufacture a highly crystalline fine nickel powder with an extremely narrow particle size distribution. The oxygen partial pressure during the thermal decomposition is preferably 10?2 Pa or less, and a metal other than nickel, a semimetal and/or a compound of these may be added to the nickel nitrate hydrate melt to manufacture a highly crystalline nickel alloy powder or highly crystalline nickel composite powder. The resultant powder is suited in particular to thick film pastes such as conductor pastes for manufacturing ceramic multilayer electronic components.

Abstract: A nickel powder with a mean particle size of 0.05 to 1.0 ?m, the nickel powder comprising a thin oxidized layer of nickel on a surface thereof and having an oxygen content of 0.3 to 3.0 wt. % and a carbon content of 100 ppm or less per specific surface area of 1 m2/g of the powder, in a weight proportion of carbon to the nickel powder of unit weight. When the powder is used for a conductive paste for forming inner electrode layers of a multilayer electronic component, it enables the decrease in the residual carbon amount after a binder removal process, thereby making it possible to obtain a multilayer ceramic electronic component with excellent electric characteristics and high reliability in which electrode layers excelling in continuity are formed without decreasing the strength and electric characteristics of the electronic component or creating structural defects.

Abstract: A method of manufacturing a highly crystallized phosphor powder, comprising: making a raw material solution containing metal elements and/or semimetal elements that will be constituents of the phosphor into fine liquid droplets, subjecting the liquid droplets to decomposition by heating at a temperature of 500 to 1800° C. to produce hollow precursor particles and/or porous precursor particles, heating the precursor particles to crystallize the precursor particles while maintaining the hollow or porous form, and grinding the crystallized particles down to a predetermined particle size. The obtained phosphor powder is a high luminance inorganic phosphor powder that is extremely fine, and yet has few defects on the surface of or inside the powder, and hence has excellent crystallinity and light emission characteristics, and provides a phosphor composition useful for producing a phosphor layer with high coverage and high luminance of light emission.

Abstract: Metal particles that can be alloyed with rhenium are dispersed as a main component in a gas phase, a rhenium oxide vapor is made to be present around these particles, the rhenium oxide is reduced, and the rhenium precipitated on the surface of the main component metal particles as a result of this reduction is diffused under a high temperature into the main component metal particles, which gives a rhenium-containing alloy powder including the main component metal and rhenium. The powder thus obtained preferably contains 0.01 to 50 wt % rhenium, has an average particle size of 0.01 to 10 ?m, and is made into a conductor paste by being uniformly mixed and dispersed in an organic vehicle along with other additives as needed.

Abstract: A method for manufacturing a highly-crystallized double oxide powder composed of a single crystal phase which can be used as a phosphor material, a dielectric material, a magnetic material, etc. The method involves forming fine droplets of a raw material solution containing a raw material compound that includes at least one metal element and/or at least one semi-metal element that constitutes a double oxide, and heating these droplets at a high temperature, wherein the raw material solution is a solution which exhibits only one main peak attributable to the decomposition reaction of the raw material compound or a reaction intermediate thereof in a DTA profile when the solution is dried and solidified and subjected to TG-DTA measurement.

Abstract: A method for manufacturing a highly-crystallized oxide powder, wherein an oxide powder is produced by ejecting a starting material powder containing at least one metal element and/or semimetal element, which will become a constituent component of the oxide, into a reaction vessel together with a carrier gas through a nozzle; and heating the starting material powder at a temperature higher than the decomposition temperature or reaction temperature thereof and not lower than (Tm/2)° C., where Tm° C. stands for a melting point of the oxide, in a state in which the starting material powder is dispersed in a gas phase at a concentration of not higher than 10 g/L. In the above method, the starting material powder may be mixed and dispersed in the carrier gas by using a dispersing machine prior to being ejected into the reaction vessel through a nozzle.