Abstract: The present invention provides a flame-retardant resin composition which comprises 100 parts by weight of a thermoplastic resin (A) and 0.1 to 30 parts by weight of one or more of organic phosphorus compounds (B) represented by the following formula (1) ##STR1## wherein X is ##STR2## R.sub.1, R.sub.2, R.sub.3 and R.sub.4 independently represent a phenyl group or a xylyl group with at least one being a phenyl group and at least one being a xylyl group, and n is a positive integer.The flame-retardant resin composition of the present invention is excellent in heat resistance, impact strength in the form of thin-walled moldings and blooming-free property on the surface of articles molded therefrom.

Abstract: An oleophilic molybdenum compound comprising an aliphatic amine group and a heteropolyanion group containing at least one molybdenum atom as a polyatom is disclosed. The oleophilic molybdenum compound is a catalyst precursor capable of being changed, in the hydroconversion reaction system, to a catalyst having excellent catalytic activity in hydroconversion of a hydrocarbon feedstock to a hydrocarbon product having a decreased molecular weight. The oleophilic molybdenum compound is efficiently produced from an aliphatic amine and a heteropolyacid.