Abstract: Discriminating radioactive nuclides of a gamma ray source and nondestructively measuring an image concentration and spatial distribution of a gamma ray by radioactive nuclides. A visualizing apparatus having a container 1 including a gamma ray source 2; a gamma ray detector 7 around the container 1 which detects gamma rays through a collimator 6; a gamma ray detection signal processing device 9 which processes a gamma ray detection signal measuring energy and counted value thereof; an energy discrimination processing device 10 which performs discrimination and intensity analysis of radioactive nuclides by performing spectrum analysis of gamma ray energy and intensity measured for each unit time or position; an imaging calculation processing device 11 which forms images of concentration and space distribution of the gamma ray source for each discriminated radioactive nuclide; and an image display device 12 which performs visual display based on a result of the calculation processing.

Abstract: To discriminate radioactive nuclides of a gamma ray source included in an apparatus and the like, and to nondestructively measure and image concentration and spatial distribution of gamma ray by radioactive nuclide.

Abstract: An apparatus for non-destructively inspecting an arbitrary heat exchanger tube among a group of heat exchanger tubes. The apparatus includes a radiation detector inserted in a heat exchanger tube to be inspected, at least one radiation source inserted in a plurality of heat exchanger tubes surrounding the heat exchanger tube to be inspected, and a CT processing unit. A cross section of the heat exchanger tube to be inspected is imaged by the CT processing. Also, by setting at least one radiation source in an inner portion of the heat exchanger tube, on the inner side of a group of heat exchanger tubes or on the outer side of the group of heat exchanger tubes, and by setting at least one radiation detector carrying a collimator on the outer side of the group of heat exchanger tubes, a cross section of the group of heat exchanger tubes can be imaged by the CT processing.

Abstract: An intermediate heat exchanger-incorporated type steam generator having an intermediate heat exchanger tube 20 and a steam generating heat exchanger tube 22 disposed separately in a vessel 10 storing a secondary coolant 14 therein. A pump mechanism is made of an electromagnetic pump mechanism formed by an electromagnetic driving coil 24 provided on an outer circumference of the vessel and a magnetic core 26 attached to an inner cylinder 12 disposed in the vessel. At least one porous plate or slotted plate 18 is preferably disposed between the intermediate heat exchanger tube and steam generating heat exchanger tube.

Abstract: An apparatus for non-destructively inspecting an arbitrary heat exchanger tube among a group of heat exchanger tubes in which a multiplicity of heat exchanger tubes are arranged. The apparatus comprises a radiation detector 12 inserted in a heat exchanger tube 10a to be inspected, at least one radiation source 14 inserted in a plurality of heat exchanger tubes surrounding the heat exchanger tube 10a to be inspected, and a CT processing unit 16 for subjecting radiation strength signals detected by the radiation detector 12 to a CT processing. A cross section of the heat exchanger tube 10a to be inspected is imaged by the CT processing.

Abstract: An intermediate heat exchanger-incorporated type steam generator having two functions of an intermediate heat exchanger and a steam generator and capable of simplifying a secondary cooling system.

Abstract: A heat exchanger having an intermediate heating medium is provided. A multiplicity of inner tubes 2 are disposed in a shell 1 of a heat exchanger 10. A low-temperature heating medium Y (water) flows in these inner tubes and a high-temperature heating medium X (liquid sodium) flows in the shell. These inner tubes are divided into a plurality of groups so that each group has a plurality of said inner tubes. The plural inner tubes constituting one group are disposed in one outer tube 3, and an intermediate heating medium Z chemically inactive with respect to both the high-temperature heating medium and the low-temperature heating medium and excellent in heat transferring performance is passed through each outer tube. The possibility that the high-temperature heating medium and the low-temperature heating medium contact each other can be reduced to an extremely low level.

Abstract: A heat exchanger having an intermediate heating medium is provided. A multiplicity of inner tubes 2 are disposed in a shell 1 of a heat exchanger 10. A low-temperature heating medium Y (water) flows in these inner tubes and a high-temperature heating medium X (liquid sodium) flows in the shell. These inner tubes are divided into a plurality of groups so that each group has a plurality of said inner tubes. The plural inner tubes constituting one group are disposed in one outer tube 3, and an intermediate heating medium Z chemically inactive with respect to both the high-temperature heating medium and the low-temperature heating medium and excellent in heat transferring performance is passed through each outer tube. The possibility that the high-temperature heating medium and the low-temperature heating medium contact each other can be reduced to an extremely low level.

Abstract: An autonomous, decentralized fast breeder reactor includes a single reactor main vessel which houses a plurality of small-size reactor subsystems each having a small-scale fast breeder reactor core, and a plurality steam generator subsystems. These subsystems function in an autonomous manner and are caused to undergo a heat transfer with one another by a coolant circulating naturally through the interior of the main vessel, thereby constructing a cooperatively operating system. Steam generated by the steam generators is introduced to a turbine system and utilized in generating electricity. The condensate from the turbines is cooled by a heat accumulating pool, and the heat is utilized in a separate system. The entire system is installed underground and use is made of the difference in elevation. Use also is made of solid bedrock to construct a housing facility for the reactor.