Abstract: A maintenance management device which individually manages maintenance times at which to perform maintenance using a plurality of constituent elements, which are equipped in an exchangeable manner to a plurality of equipment positions of a component mounting machine to operate, as management targets, and the maintenance management device includes a remaining operation number calculating section which calculates respective remaining operation numbers of each of the plurality of constituent elements, an operation frequency ascertaining section which ascertains respective operation frequencies of the constituent elements at the plurality of equipment positions according to a type of the board, and a guide section which performs guidance of equipment positions of the constituent elements based on the remaining operation number and the operation frequency when a worker equips the constituent elements.

Abstract: A maintenance management device which individually manages maintenance times at which to perform maintenance using a plurality of constituent elements, which are equipped in an exchangeable manner to a plurality of equipment positions of a component mounting machine to operate, as management targets, and the maintenance management device includes a remaining operation number calculating section which calculates respective remaining operation numbers of each of the plurality of constituent elements, an operation frequency ascertaining section which ascertains respective operation frequencies of the constituent elements at the plurality of equipment positions according to a type of the board, and a guide section which performs guidance of equipment positions of the constituent elements based on the remaining operation number and the operation frequency when a worker equips the constituent elements.

Abstract: A method of oxidizing a carbon-carbon double bond wherein the compound having the carbon-carbon double bond is suppressed, the unreacted compound is separated from the reaction product, and thereafter the thus obtained unreacted compound is again used for the oxidizing reaction; and a process for producing an oxidized compound utilizing such an oxidizing method. When this method is used, an intended oxidized compound can be obtained with high selectivity and high productivity.

Abstract: A method of oxidizing a carbon-carbon double bond wherein the compound having the carbon-carbon double bond is suppressed, the unreacted compound is separated from the reaction product, and thereafter the thus obtained unreacted compound is again used for the oxidizing reaction; and a process for producing an oxidized compound utilizing such an oxidizing method. When this method is used, an intended oxidized compound can be obtained with high selectivity and high productivity.

Abstract: A metal-made water-cooling jacket for electric arc furnaces, characterized by comprising an Al diffusion layer having a thickness ranging from 200 to 800 &mgr;m, the Al concentration of the outermost surface of the Al diffusion layer being from 10 to 50 wt. %, formed on the surface of the metal by calorizing treatment.