Abstract: A method for preparing a pyrophosphate-tin composition labelled with 99.sup.m technetium for medical diagnosis by scintigraphy, especially bone scintigraphy. A pyrophosphate solution and a freshly prepared stannous chloride solution are mixed together and then neutralized to a pH within the range of 5 to 7, the mixture is eventually lyophilized in order to obtain a pyrophosphate-tin complex in powder form which is then mixed with a solution containing 99.sup.m Tc, the last-mentioned final step of the method being carried out at the moment of use. The complex has a pyrophosphate-tin molecular ratio of at least 30.

Abstract: A nuclear fuel sub-assembly comprises a bundle of fuel pins provided with helical spacers and located within a shroud for the coolant. The sub-channels at the periphery of the bundle are restricted in order that the rate of flow matches the heat transfer surfaces in all sub-channels. For this purpose the spacers of the outer pins project radially by an extent smaller than the spacers of the inner pins. In addition longitudinal ribs may be provided in the outer sub-channels.

Abstract: A method of collective orientation of the molecules of a mesomorphous liquid crystal, in which each of two oppositely-facing walls of a liquid-crystal cell is covered with a conductive deposit forming an electrode and with a thin film of a substance which exhibits properties of orientation of smectic crystals in solid phase; the mesomorphous liquid crystal is placed in contact with the two thin films and the molecules of said liquid crystal are aligned with those of the thin film.

Abstract: A method for manufacturing integrated circuits, said method comprising the steps of:Providing a first set of conductive zones on each of these portions of a substrate where electrical contacts are to be made, after having suitably doped said substrate with semiconductive material,Providing a selective insulating layer, so that the upper portions of said conductive zones be flush with the surface of said selective insulating layer, andProviding thereabove a second set of conductive zones adapted to constitute intended connections between said upper portions.Said method can be applied to the manufacture of MOS transistors.

Abstract: This invention relates to methods of measuring magnetic fields and a magnetometer for performing the method.According to the method an alternating magnetic field is applied to a thin magnetic film along its axis of difficult magnetization.The alternating magnetic field applied to the film has an amplitude which is less than the anisotropy field of the film, the direction of magnetization of the film then undergoing an oscillation without reversal.An electrical signal representing variations per unit of time of the magnetic induction in the film is withdrawn and analyzed and to effect the analysis the component of the magnetic field is measured at any of the odd harmonic frequencies of the electrical signal. The electrical signal is obtained by collecting the voltage at the terminals of a conducted loop surrounding the film and having its axis directed along the easy axis of the film.