Abstract: In a method for enriching oxidized ores by froth flotation, use is made, as collector, of a combination comprising : at least a first compound selected among amino-l-alkane products having the general formula R.sub.1 - (NH CH.sub.2 CH.sub.2 CH.sub.2)n NH.sub.2, wherein R.sub.1 is a saturated or unsaturated straight- or branched-chain hydrocarbon group containing from 8 to 18 carbon atoms, and n is an integer ranging from 0 to 3, and at least a second compound selected among amino-ether products having one amino function and at least one ether function, of the general formula R.sub.2 - O - (CH.sub.2 CH.sub.2 O)n - CH.sub.2 CH.sub.2 CH.sub.2 NH.sub.2, wherein R.sub.2 is a saturated or unsaturated straight- or branched- chain hydrocarbon group containing from 2 to 18 carbon atoms, and n is an integer ranging from 0 to 2.

Abstract: The method for the inhibition of corrosion of ferrous metals in an aqueous medium consists in adding to the aqueous medium 10 to 2000 ppm of a mixture constituted by a water-soluble complex salt of a metal of groups II to VIII of the periodic table and of a hydroxycarboxylic acid and by a phosphoric ester of alkanolamine.

Abstract: The invention relates to bituminous binder compositions containing in the proportion of 0.5 to 2% by weight of the bitumen used, a mixture of polynitrogenous compounds such as those obtained by reacting polyalkylene polyamines having the general structure: R -- NH (CH.sub.2 -- CH.sub.2 -- CH.sub.2 -- NH).sub.n -- H with formic acid while removing the reaction water. The main component consists of a tetrahydropyrimidine substituted on nitrogen by means of a long linear chain comprising one or a plurality of amine groups having the general structure: ##STR1## wherein R is a saturated or unsaturated linear hydrocarbon comprising 8 to 22 carbon atoms, n is an integer from 2 to 5 and p another integer equal to (n - 1), that is from 1 to 4.