Abstract: A method for recycling metal parts contaminated by radioactive elements, in particular by .alpha.-emitters, includes forming a melt and a slag from the metal parts and then separating the slag from the melt. The radioactive elements are oxidized prior to the formation of the melt and the slag. For that purpose, the contaminated metal parts are exposed to an oxygen-containing atmosphere for a period at a temperature below the melting temperature of the metal parts.

Abstract: A method for reprocessing metal parts that are radioactively contaminated with uranium includes smelting the metal parts so that a melt and a slag are formed. U.sub.235 -depleted uranium is admixed with the metal parts and/or the melt and/or the slag. It is contemplated for the U.sub.235 -depleted uranium to be admixed in the form of uranium glass.

Abstract: A waste disposal site, such as an ultimate disposal site for radioactive substances, includes installed waste having hollow spaces remaining therebetween. Packing material fills the remaining spaces. At least one substance to which gaseous toxic substances such as radioactive gases adhere, is admixed with the packing material.

Abstract: A method is disclosed for the production of n-doped silicon single crystals, each having a dish-shaped specific electrical resistance profile in a radial direction about a central axis of the crystal. A silicon single crystal is exposed to a pattern of radiation with neutrons according to the reaction 30.sub.Si (n,.gamma.) 31.sub.Si .sup..beta.-.fwdarw. 31.sub.P. The neutron radiation causes a weaker doping concentration in marginal regions of the crystals due to the production of fewer phosphorus atoms. Either p-conductive silicon crystals or n-conductive silicon crystals may be utilized as an initial material for exposure to the neutron radiation.

Abstract: An apparatus for doping a semiconductor crystalline rod by nuclear or radiogenic reactions comprised of a hollow irradiation housing having axially and rotatably movable rod support means within the chamber thereof and a neutron conductive sleeve connected with the housing and providing communication between a neutron source and the housing chamber. Accurate and controlled doping of a semiconductor crystalline rod mounted on the rod support means within the housing chamber occurs via controlled rod movement in relation to the neutron source.

Abstract: Si monocrystals of the n-type are produced by zone melting polycrystalline Si rods under conditions sufficient to produce monocrystal rods, measuring the specific conductivity of such monocrystal rods and subjecting such monocrystal rods to a controlled radiation by thermal neutrons based on the measured conductivity to produce a desired degree of n-conductivity in the ultimately attained rods.

Abstract: A homogeneously doped p-conductive semiconductor material is produced by irradiating a desired semiconductor material with .gamma.-photons which trigger nuclear reactions within such irradiated material to form dopant atoms therein.

Abstract: A semiconductor layer, such as an epitaxial layer on a suitable substrate is subjected to controlled bombardment by neutrons whereby the atoms of the semiconductor layer are converted via nuclear reaction into doping material atoms.