Abstract: 1. A method of making a fuel-containing structure for nuclear reactors, comprising providing an assembly comprising a plurality of fuel units; each fuel unit consisting of a core plate containing thermal-neutron-fissionable material, sheets of cladding metal on its bottom and top surfaces, said cladding sheets being of greater width and length than said core plates whereby recesses are formed at the ends and sides of said core plate, and end pieces and first side pieces of cladding metal of the same thickness as the core plate positioned in said recesses, the assembly further comprising a plurality of second side pieces of cladding metal engaging the cladding sheets so as to space the fuel units from one another, and a plurality of filler plates of an acid-dissolvable nonresilient material whose melting point is above 2000.degree. F.

Abstract: The compounds of S-(2-dialkylaminoalkyl) alkyl phosphonothioic acids and hod of preparing said compounds possessing anticholinesterase activity comprising an aqueous solution which comprises dialkylaminoalkyl chloride salts which are converted to their corresponding dialkylmonoalkyl ammonium ions and alkylphosphonothioic acids forming a reaction mixture. The latter mixture is placed on a cation exchange resin with subsequent addition of water as an eluting agent giving rise to fractions containing the desired compounds.