Abstract: Disclosed is a ferrite material having low magnetic losses at frequencies of about 1 megahertz to 100 megahertz, and having firing and sintering temperatures lower than about 1000.degree. C. The material is a nickel-zinc-copper material with cobalt substitution, particularly well suited to the making of magnetic cores and more specifically to the making of micro-inductors.

Abstract: The disclosure relates to a family of luminophors Ba.sub.z -Al.sub.12-x Mn.sub.x O.sub.19 with 0.8.ltoreq.z.ltoreq.1.3, wherein x ranges from 0.2 to 0.7 and has a time of decay, to 10% of the light energy emitted, of less than about 15 ms. It also relates to a method for the manufacture of this family of luminophors having a time of decay, to about 10% of the initial light intensity emitted, of less than about 15 ms. It also relate to a method for the manufacture of this family of luminophors, using a primary vacuum step in order to obtain a neutral or reductive atmosphere with an oxygen content of less than about 10 particles per million (ppm). This method has the great value of enabling the formation of barium hexa-aluminate with a high manganese content to lower the decay time while, at the same time, preserving high luminous efficiency. Application to high-definition television.