Abstract: The novel compounds .omega.-N-disubstituted aminoalkanoic acid N'-amides of the formula ##STR1## in which R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are identical or different and denote branched-chain or straight-chain alkyl radicals of from 7 to 20 carbon atoms, R.sup.2 and R.sup.4 may also denote a preferably mononuclear aralkyl or aryl radical and n denotes an integer of from 3 to 5, the total number of carbon atoms in the radicals R.sup.1 to R.sup.2 and in R.sup.3 and R.sup.4 being at least 16, are added in small quantities to gasoline and effect cleaning of the carburetor and obviate the formation of deposits on the valves.

Abstract: The method of stabilizing mineral oil and its refinery products by addition thereto of a small stabilizing amount of alternating copolymers of the type. . . A -- B -- A -- B -- A . . .in which A denotes the structural unit of the general formula--C(R.sup.1)(R.sup.2) - CH.sub.2 --where R.sup.1 denotes hydrogen or alkyl of from 1 to 8 carbon atoms and R.sup.2 has the meanings stated for R.sup.1 or denotes a phenyl group, and in which B stands for structural units of the general formulae ##STR1## where R.sup.3 denotes a saturated hydrocarbon radical of from 8 to 20 carbon atoms and R.sup.4 denotes hydrogen or alkyl of from 8 to 20 carbon atoms.

Abstract: Otto cycle engine fuels, for example gasoline, can be improved to such an extent by additives that no deposits or residues form in the carburetor or on the valves. In accordance with the invention esters, amides or imides of hydroaromatic polycarboxylic acids are added which are very effective in cleaning the carburetor and the valves.