摘要:
Process for increasing the density and improving the homogeneity of Chevrel phase powders and Chevrel phase wire obtained using said process. Chevrel phase powers are compounds of lead, mobydenum, and sulfur. Metallic additives in the range of 0.5% to 20% by weight are introduced in the Chevrel phase powders by a physical or chemical process. The melting temperature of the metallic additives is lower than the synthesis temperature of the Chevrel phase powders so as to increase the homogeneity. The wires obtained using this process are capable of generating high magnetic fields.
摘要:
The invention relates to a method and an installation for identifying an object. An identification mark (12) is made on the actual object using electrical discharges (28) between a metal tip (21), such as that of a local-probe microscope, and the substrate (22) formed by the object. The discharges (28) are produced through a composite dielectric medium (25) and produce an impression (23) which can be identified by read means, such as a microprobe, and has a particular physical nature and/or a particular chemical composition. Thanks to these characteristics, it is possible to obtain a very secure identification and authentication mark that can be applied directly to the actual object to be identified or authenticated.
摘要:
The invention is concerned with a resistive fault current limiter (FCL) based on thin superconducting films. The FCL comprises constrictions (2) with a reduced critical current, separated by connecting paths (3). Upon occurrence of a fault current, the former turn resistive simultaneously and build up a resistance which allows the applied voltage to drop entirely only over the constrictions. Only at a later stage, the connecting paths become resistive and dissipate energy. The thickness and width of an electrical bypass determine said normal resistivities of the constrictions and the connecting paths.