Abstract: A composition which is stable in a medium in which the pH is greater than or equal to 5.5 and which permits the release of an active substance in a medium in which the pH is less than or equal to 3.5, comprising the active substance, which contains inclusions of, or which is completely or partially covered by, a pH sensitive material whose extent and/or rate of swelling is greater in an acidic medium than in a neutral medium, and a coating of a hydrophobic layer.

Abstract: A composition for coating a biologically active substance which is stable in a medium in which the pH is greater than or equal to 5 and which permits the release of the active substance in a medium in which the pH is less than or equal to 3.5, comprises a film-forming, water-insoluble binder which possesses controlled hydrophilicity and is optionally slightly sensitive to pH variations, and a substance which is sensitive to pH variations (e.g. an inorganic filler, simple aminated substance, basic polymer or copolymer, chitosan). Pellets for feeding to ruminants consist of a core containing the biologically active substance, e.g. methionine or lysine, coated with this substance.

Abstract: An organopolysiloxane composition is facilely photocured, e.g., into a variety of non-stick coatings, by subjecting to a photocross-linking amount of ultraviolet irradiation, admixture of (i) a polysiloxane comprised of hydroxysilyl groups devoid of Si-H bonds and containing no organic radicals which include sites of activated ethylenic unsaturation, and (ii) an aminopolyalkoxysilane.

Abstract: Photopolymerizable, liquid, storage stable organopolysiloxanes having viscosities of from 60 mPa.s to 2,000 mPa.s at 25.degree. C., are prepared by reacting (i) an .alpha.,.omega.-dihydroxydiorganopolysiloxane oil having a viscosity ranging from about 70 to 500 mPa.s at 25.degree. C., with (ii) a silane having the formula Z(G)SiR.sub.a (Q).sub.3-a wherein Z is CH.sub.2 .dbd.C(R')--COO-- or HS--, and further wherein the symbols R, which may be the same or different, are methyl, ethyl, n-propyl, vinyl or phenyl, R' is hydrogen or methyl, the symbols Q, which may be the same or different, are methoxy, ethoxy, n-propoxy, .beta.-methoxyethoxy and, when any two are taken together, the divalent radical --O--(CH.sub.3).sub.2 --C(CH.sub.3).sub.2 --O--, G is a linear or branched chain alkylene radical having from 1 to 8 carbons, and a is a number ranging from 0 to 2; and with the molar ratio of the hydroxyl functions comprising the oil (i) to the Q radicals comprising the silane (ii) ranging from 0.1 to 0.95.