摘要 |
PCT No. PCT/FR87/00024 Sec. 371 Date Nov. 13, 1987 Sec. 102(e) Date Nov. 13, 1987 PCT Filed Jan. 22, 1987 PCT Pub. No. WO87/04420 PCT Pub. Date Jul. 30, 1987.Particulate compositions of rare earth oxides wherein the particles are present in the form of single crystals of homogeneous size and morphology, the dimensions of which are less than or equal to 10 mu m and greater than approximately 0.05 mu m and that at least 80% of the particles have dimensions varying within a range of x+/-0.2 x, x being the mean dimension of the particles of the composition under consideration, with the understanding that the variation of the range of +/-0.2 x is not less than +/-0.1 mu m. |