Abstract: It is provided a steel with composite plating film providing rust prevention over a long time period and a method of manufacturing thereof. A composite plating film 24 is formed on a metal material 21. The film 24 has a plating film 23 made of a sacrificial anode metal and photocatalyst particles 22 dispersed and fixed in the plating film 23. The photocatalyst particle has a main body composed of a photocatalyst and a semiconductor material supported thereon. The composite plating film 24 is formed on the surface of the metal material 21 by electroplating, hot-dipping, chemical plating or the like.

Abstract: It is provided a steel with composite plating film providing rust prevention over a long time period and a method of manufacturing thereof. A composite plating film 24 is formed on a metal material 21. The film 24 has a plating film 23 made of a sacrificial anode metal and photocatalyst particles 22 dispersed and fixed in the plating film 23. The photocatalyst particle has a main body composed of a photocatalyst and a semiconductor material supported thereon. The composite plating film 24 is formed on the surface of the metal material 21 by electroplating, hot-dipping, chemical plating or the like.

Abstract: It is provided a steel with composite plating film providing rust prevention over a long time period and a method of manufacturing thereof. A composite plating film 24 is formed on a metal material 21. The film 24 has a plating film 23 made of a sacrificial anode metal and photocatalyst particles 22 dispersed and fixed in the plating film 23. The photocatalyst particle has a main body composed of a photocatalyst and a semiconductor material supported thereon. The composite plating film 24 is formed on the surface of the metal material 21 by electroplating, hot-dipping, chemical plating or the like.

Abstract: The inventive photoreactive device has a semiconductor and an oxidation-reduction material. The semiconductor has a conduction band with a potential and being capable of producing electrons under the irradiation of light on the semiconductor. The oxidation-reduction material has a redox potential being positive compared with the potential of the conduction band. The semiconductor supplies electrons into the oxidation-reduction material to reduce it under the irradiation of light for storing the electrons. The stored electrons are discharged from the oxidation-reduction material into a metal material to prevent the corrosion of the metal material.

Abstract: The inventive photoreactive device has a semiconductor and an oxidation-reduction material. The semiconductor has a conduction band with a potential and being capable of producing electrons under the irradiation of light on the semiconductor. The oxidation-reduction material has a redox potential being positive compared with the potential of the conduction band. The semiconductor supplies electrons into the oxidation-reduction material to reduce it under the irradiation of light for storing the electrons. The stored electrons are discharged from the oxidation-reduction material into a metal material to prevent the corrosion of the metal material.

Abstract: A reading method for a magnetic tape having a series of frames each constituted of a predetermined number of data blocks. For reading any given frame of the tape more quickly than heretofore in the face of a possible read error or errors, there is employed a buffer memory capable of temporarily storing the data from one complete frame preparatory to delivery to a host system. As the succesive blocks of the frame are read by an electromagnetic transducer, the data from each block is checked for an error by a check signal read from that block, and the data from only those blocks where no read error has been found are written on the buffer memory. Then, in event a read error has been found on more than a predetermined number (e.g. one) of blocks, all the blocks of the same frame are reread. During this rereading, the data from only those blocks where a read error has been found during the initial reading are checked for an error and written on the buffer memory if no error has been found.