Abstract: There is described a method and an apparatus which comprises a reader for reading document characteristics, circuitry permitting the formation of a message confirming the holder identity, a computer connected to said reader and message means, said computer is so designed as to be able to perform from those data obtained by the reader and said means, and possibly from other remotely-conveyed data, a mathematical processing including one or a plurality of encipherings according to a public-key cryptography method and making use therefor but of public keys, means being provided to check with said computer, by a third party, and/or remotely with another computer, the expected match between said collected data, a non-secret number independent from the document, and identification data present unscrambled on the document, which match is disclosed by the mathematical processing.

Abstract: There is described a method for extracting fluoride ions from a nuclear fuel solution which comprises treating said solution with a solid phase from hydrated silica, such as silica gel and/or silicic acid, to bind the fluorine to the silicium, said solid phase then being separated from said solution.

Abstract: There is described a method for localizing a leaking rod from a nuclear fuel assembly, in which for each rod in an assembly, the radio-activity in at least two discrete rod rows in which said rod lies is measured and a leaking rod is localized by sensing a lowering of the radio-activity in the tested rows where said rod lies relative to the radio-activity in an identical row of non-leaking rods.There is further described an equipment for the working of this method.

Abstract: A neutron-irradiation dose monitor is described as comprising a first couple of wires of different nature, soldered to one another by the one end thereof and a second couple of wires of different nature, soldered to one another by the one end thereof, the wires of both couples having thermo-electric properties that vary differently according to the integrated neutron flow.

Abstract: There is described a method for sodium-deactivating and/or stocking irradiated nuclear fuel elements, said elements being contacted with a fluid, in which use is made as fluid, of a molten salt mixture which is uncorrosive for the element stainless steels, inert relative to uranium and plutonium oxides by the deactivating temperature and reactive with sodium metal without producing a detonating gas.