Abstract: A method of producing an apatite crystal includes the steps of preparing an apatite single crystal expressed by the general formula M25(PO4)3X (M2 being at least atomic element selected from the group consisting of divalent alkaline-earth metals and Eu, and X is at least one atomic selected from the group consisting of halogens); placing the apatite single crystal into a space controllable to a predetermined atmosphere; supplying water vapor into the space; and heating such that the atmosphere in the space is within a 1000° C. to 1400° C. range.

Abstract: Provided is an efficient method for producing nickel powder from a solution containing a nickel ammine complex, the method including adding seed crystals to a solution containing a nickel ammine complex and subjecting the resulting mixture to hydrogen reduction under high temperatures and high pressures to produce nickel powder, which makes it possible to maintain the quality of the nickel powder produced and reduce the amount of the seed crystals used. The method for producing nickel powder is characterized by adding seed crystals and a dispersant having an anionic functional group to the solution containing a nickel ammine complex to form a mixture slurry, and subjecting the mixture slurry to pressurized hydrogen reduction treatment by blowing hydrogen into the mixture slurry in a high temperature and high pressure atmosphere to cause a reduction reaction, thereby reducing the nickel ammine complex in the mixture slurry to obtain nickel powder.

Abstract: Provided is nickel powder obtained by adding seed crystals to a nickel ammine complex solution and performing hydrogen reduction reaction under high temperatures and high pressures, wherein the nickel powder does not produce dust during handling, and a container can be efficiently filled with the nickel powder. The method for producing nickel powder includes: adding seed crystals and a surfactant having a nonionic or anionic functional group to a solution containing a nickel ammine complex to forma mixed slurry; and subjecting the mixed slurry to hydrogen reduction under high temperature and high pressure conditions in a pressure vessel to obtain nickel powder from the mixed slurry.

Abstract: Provided is a method for producing fine nickel powder used as suitable seed crystals for producing nickel powder from a solution containing a nickel ammine sulfate complex. The method for producing nickel powder sequentially comprises: a mixing step of adding, to a solution containing a nickel ammine sulfate complex, an insoluble solid which is insoluble in the solution to form a mixed slurry; a reduction and precipitation step of charging a reaction vessel with the mixed slurry and then blowing hydrogen gas into the mixed slurry in the reaction vessel to reduce nickel complex ions contained in the mixed slurry to form nickel precipitate on a surface of the insoluble solid; and a separation step of separating the nickel precipitate on the surface of the insoluble solid from the surface of the insoluble solid to form nickel powder.

Abstract: Provided is a method for producing nickel powder from a nickel ammine sulfate complex solution, comprising treatment steps of: (1) a seed crystal production step of producing nickel powder having an average particle size of 0.1 to 5 ?m; (2) a seed crystal addition step of adding the nickel powder obtained in the step (1) as seed crystals to form a mixed slurry; (3) a reduction step of forming a reduced slurry containing nickel powder formed by precipitation of a nickel component in the mixed slurry on the seed crystals; and (4) a growth step of performing solid-liquid separation to separate and recover the nickel powder as a solid phase component and then blowing hydrogen gas into a solution prepared by adding the nickel ammine sulfate complex solution to the recovered nickel powder to grow the nickel powder to form high purity nickel powder.

Abstract: Provided is a method for producing fine nickel powder used as suitable seed crystals for producing nickel powder from a solution containing a nickel ammine sulfate complex. The method for producing nickel powder sequentially includes: a mixing step of adding, to a solution containing a nickel ammine sulfate complex, a dispersant containing a sulfonate and an insoluble solid which is insoluble in the solution to form a mixed slurry; a reduction and precipitation step of charging a reaction vessel with the mixed slurry and then blowing hydrogen gas into the mixed slurry in the reaction vessel to reduce nickel complex ions contained in the mixed slurry to form nickel precipitate on a surface of the insoluble solid; and a separation step of separating the nickel precipitate on the surface of the insoluble solid from the surface of the insoluble solid to form nickel powder.

Abstract: A method of producing an apatite crystal includes the steps of preparing an apatite single crystal expressed by the general formula M25(PO4)3X (M2 being at least atomic element selected from the group consisting of divalent alkaline-earth metals and Eu, and X is at least one atomic selected from the group consisting of halogens); placing the apatite single crystal into a space controllable to a predetermined atmosphere; supplying water vapor into the space; and heating such that the atmosphere in the space is within a 1000° C. to 1400° C. range.

Abstract: Provided is nickel powder obtained by adding seed crystals to a nickel ammine complex solution and performing hydrogen reduction reaction under high temperatures and high pressures, wherein the nickel powder does not produce dust during handling, and a container can be efficiently filled with the nickel powder. The method for producing nickel powder includes: adding seed crystals and a surfactant having a nonionic or anionic functional group to a solution containing a nickel ammine complex to forma mixed slurry; and subjecting the mixed slurry to hydrogen reduction under high temperature and high pressure conditions in a pressure vessel to obtain nickel powder from the mixed slurry.

Abstract: Provided is an efficient method for producing nickel powder from a solution containing a nickel ammine complex, the method including adding seed crystals to a solution containing a nickel ammine complex and subjecting the resulting mixture to hydrogen reduction under high temperatures and high pressures to produce nickel powder, which makes it possible to maintain the quality of the nickel powder produced and reduce the amount of the seed crystals used. The method for producing nickel powder is characterized by adding seed crystals and a dispersant having an anionic functional group to the solution containing a nickel ammine complex to form a mixture slurry, and subjecting the mixture slurry to pressurized hydrogen reduction treatment by blowing hydrogen into the mixture slurry in a high temperature and high pressure atmosphere to cause a reduction reaction, thereby reducing the nickel ammine complex in the mixture slurry to obtain nickel powder.

Abstract: Provided is a method for producing nickel powder from a nickel ammine sulfate complex solution, comprising treatment steps of: (1) a seed crystal production step of producing nickel powder having an average particle size of 0.1 to 5 ?m; (2) a seed crystal addition step of adding the nickel powder obtained in the step (1) as seed crystals to form a mixed slurry; (3) a reduction step of forming a reduced slurry containing nickel powder formed by precipitation of a nickel component in the mixed slurry on the seed crystals; and (4) a growth step of performing solid-liquid separation to separate and recover the nickel powder as a solid phase component and then blowing hydrogen gas into a solution prepared by adding the nickel ammine sulfate complex solution to the recovered nickel powder to grow the nickel powder to form high purity nickel powder.

Abstract: Provided is a method for producing fine nickel powder used as suitable seed crystals for producing nickel powder from a solution containing a nickel ammine sulfate complex. The method for producing nickel powder sequentially comprises: a mixing step of adding, to a solution containing a nickel ammine sulfate complex, an insoluble solid which is insoluble in the solution to form a mixed slurry; a reduction and precipitation step of charging a reaction vessel with the mixed slurry and then blowing hydrogen gas into the mixed slurry in the reaction vessel to reduce nickel complex ions contained in the mixed slurry to form nickel precipitate on a surface of the insoluble solid; and a separation step of separating the nickel precipitate on the surface of the insoluble solid from the surface of the insoluble solid to form nickel powder.

Abstract: Provided is a method for producing fine nickel powder used as suitable seed crystals for producing nickel powder from a solution containing a nickel ammine sulfate complex. The method for producing nickel powder sequentially includes: a mixing step of adding, to a solution containing a nickel ammine sulfate complex, a dispersant containing a sulfonate and an insoluble solid which is insoluble in the solution to form a mixed slurry; a reduction and precipitation step of charging a reaction vessel with the mixed slurry and then blowing hydrogen gas into the mixed slurry in the reaction vessel to reduce nickel complex ions contained in the mixed slurry to form nickel precipitate on a surface of the insoluble solid; and a separation step of separating the nickel precipitate on the surface of the insoluble solid from the surface of the insoluble solid to form nickel powder.

Abstract: The present invention provides a method of producing a sulfide compound semiconductor containing Cu, Zn, Sn and S, in which the method includes a solvothermal step of conducting a solvothermal reaction of Cu, Zn, Sn and S in an organic solvent, and a rod-like crystal of sulfide compound semiconductor containing Cu, Zn, Sn and S.

Abstract: Using conventional synthesis methods, when an unsaturated carboxylic acid or a derivative thereof is synthesized from a hydroxycarboxylic acid or a derivative thereof by a dehydration reaction using a catalyst, the yield has been low. Accordingly, an object of the present invention is to provide a catalyst capable of synthesizing unsaturated carboxylic acids or derivatives thereof by a dehydration reaction that produces a high yield. The synthetic catalyst comprises an apatite compound containing an alkali metal in a crystal structure thereof, and the invention further includes methods for synthesizing an unsaturated carboxylic acid and/or a derivative thereof. The methods comprise contacting the aforementioned synthetic catalyst with the hydroxycarboxylic acid and/or a derivative thereof, so as to synthesize the unsaturated carboxylic acid and/or a derivative thereof by a dehydration reaction.

Abstract: It is an object of the present invention to provide a catalyst, which solves a problem in that when an unsaturated carboxylic acid or a derivative thereof has been conventionally synthesized from a hydroxycarboxylic acid or a derivative thereof by a dehydration reaction using a catalyst, the yield has been low, and which is capable of synthesizing the unsaturated carboxylic acid or a derivative thereof at a high yield, and also to provide a synthetic method capable of synthesizing an unsaturated carboxylic acid or a derivative thereof at a high yield.

Abstract: This invention provides a fine particle composite comprising fine particles of a sulfide or sulfide complex comprising at least one element selected from the group consisting of molybdenum (Mo), rhodium (Rh), ruthenium (Ru), and rhenium (Re) and conductive fine particles via a step of preparing a solvent mixture from a compound containing conductive carbon powder, at least one compound containing an element selected from among molybdenum (Mo), rhodium (Rh), ruthenium (R), and rhenium (Re), and sulfur (S) and a step of conducting a hydrothermal or solvothermal reaction at a pressure and temperature that convert the solvent mixture into a supercritical or subcritical water or solvent.

Abstract: This invention provides a fine particle composite comprising fine powder of a sulfide or sulfide complex comprising a given element. The fine particle composite is obtained by a method for producing a fine particle composite comprising fine powder of a sulfide or sulfide complex comprising at least one element selected from the group consisting of molybdenum (Mo), rhodium (Rh), ruthenium (Ru), and rhenium (Re). Such method comprises steps of: preparing a solvent mixture from at least one compound containing an element selected from among molybdenum (Mo), rhodium (Rh), ruthenium (Ru), rhenium (Re), and sulfur (S); and subjecting the solvent mixture to a hydrothermal or solvothermal reaction. The resulting fine particle composite comprises fine particles of a sulfide or sulfide complex comprising at least one element selected from the group consisting of molybdenum (Mo), rhodium (Rh), ruthenium (Ru), and rhenium (Re).

Abstract: An appropriate catalyst is found for synthesis of an unsaturated carboxylic acid and/or a derivative thereof using as a raw material compound a hydroxycarboxylic acid and/or a derivative thereof that can easily be synthesized from a polysaccharide such as biomass-derived cellulose, and an efficient method for synthesizing the unsaturated carboxylic acid and/or the derivative thereof is provided. This method is a method for synthesizing an unsaturated carboxylic acid and/or a derivative thereof, wherein an apatite compound is used as a catalyst to synthesize the unsaturated carboxylic acid and/or the derivative thereof from a biomass-derived hydroxycarboxylic acid and/or a derivative thereof by a dehydration reaction.

Abstract: The present invention provides a method of producing a sulfide compound semiconductor containing Cu, Zn, Sn and S, in which the method includes a solvothermal step of conducting a solvothermal reaction of Cu, Zn, Sn and S in an organic solvent, and a rod-like crystal of sulfide compound semiconductor containing Cu, Zn, Sn and S.

Abstract: A production method for a coated active material that is composed of an active material, and a coating layer of an oxide that covers the active material includes a preparation step of mixing an active material, an ingredient of an oxide, and water to prepare a mixture, and a hydrothermal treatment step of hydrothermally treating the mixture to form a coating layer.