Abstract: Baths for chemical polishing of stainless steel surfaces, comprising, in aqueous solution, a mixture of hydrochloric acid, phosphoric acid and nitric acid, ferricyanide complex ions and an additive capable of decomposing nitrous acid.The baths can be used in particular for chemical polishing of heat exchangers with a very large exchange surface.

Abstract: Process for the production of a water-insoluble nitrogeneous organic base, from an aqueous solution of alkali metal bicarbonate and the base hydrochloride, according to which the solution (11) is treated with a complement of the base hydrochloride (12), and the resultant liquid (18) is treated with a basic agent (30) capable of decomposing the hydrochloride. The invention is applied to the regeneration of the amine in the process for the manufacture of sodium bicarbonate by the amines method.

Abstract: Stabilized against degradation by oxidizing liquids, based on polymers of alpha-olefins such as propylene, containing a phenolic antioxidant, a phosphonite and a sulfur-containing stabilizer chosen from the esters derived from aliphatic polyols and alkylthiodipropionic acids and from combinations of a metal sulfide with one of these esters or with an organic polysulfide and optionally also containing an organic phosphite and an anti-acid agent. These compositions exhibit outstanding resistance to the phenomenon of oxidative degradation produced particularly by the contact with hot washing products of all kinds.

Abstract: Electrically conductive polymers derived from heterocyclic polycyclic monomers formed of at least two cycles of five condensed members, each cycle containing one heteroatom, as well as a method of electrochemical polymerization by anodic oxidation of these monomers. These polymers may become part of composite electroconductive material.

Abstract: The substitution chlorination reactions of organic compounds are carried out by means of molecular chlorine, using, as a radical initiator, decachlorobutane or an octachlorobutane such as octachlorobut-1-ene or a mixture containing these two products.Good degrees of conversion and good yields are obtained at moderate temperatures.The process is, for example, applicable to the substitution chlorination of benzene and of chloroform.

Abstract: A device for avoiding flow disturbances and stagnation during the production of hollow or solid multilayer elongate structures.

Abstract: The chemical polishing of steel surfaces is carried out by bringing the latter into contact with a bath comprising, in aqueous solution, hydrochloric acid, phosphoric acid, nitric acid and ferricyanide complex ions. The invention is in particular applicable to the polishing of vessels of large dimensions made from stainless steel alloyed with chromium and with nickel.

Abstract: The block comprises a central channel (2) which feeds a first molten plastic, and at least one secondary channel (5, 10) which feeds a different molten plastic and connects to the central channel (2) upstream of the die, the central channel (2) in the connection zone, being equipped with a flat portion (11) which alters the cross-section of the channel, the said flat portion (11) being mounted in a removable piece (12) coaxial with the central channel and arranged in a guide tube (13) which intersects the central channel (2) and runs through the feed block (1), the said block being equipped with means (20), (21) for gradually withdrawing the removable piece (12) via the guide tube (13) and for replacing it by another removable piece (18) equipped with an identical or different flat portion (19).The block is particularly suitable for feeding a flat die which delivers films, sheets or composite panels.

Abstract: The composition contains, relative to the weight of calcium chloride, from 2 to 15% by weight of a potassium nitrogen compound and from 2 to 15% by weight of ammonium chloride, the weight relationship between the potassium nitrogen compound and ammonium chloride being preferably between 0.4 and 2. The composition, which has a melting point of 19 to 22.degree. C. is suitable, in particular, for heat conditioning of dwellings and of covered cultivation installations.

Abstract: The present invention provides a clear lacquer based on polyvinylidene fluoride which comprises:(a) 30 to 45 wt. % of polyvinylidene fluoride with a K value of 40 to 55,(b) 4 to 15 wt. % of an acrylate resin,(c) 33 to 50 wt. % of latent, high boiling solvent,(d) 3 to 15 wt. % of low boiling solvent,(e) 0.01 to 1.0 wt. % of flowing adjuvant,(f) 0.01 to 0.95 wt. % of light protection agent. The present invention also provides a process for coating metallic surfaces, wherein this clear lacquer is applied to a metal surface and stoved at a temperature of from 250.degree. to 350.degree. C.

Abstract: An organic solution (2) of a water-immiscible chloride of an organic cation is mixed with a basic reagent and with water (3) in a reaction chamber (1), the mixture (6) which has reacted is transferred into a phase separation chamber (5) where the organic solution of the base (8) and an aqueous phase (7) containing a solid residue are separated and at least a part of a sludge (9) formed between the organic solution and the aqueous phase which have separated is recycled into the reaction chamber (1).

Abstract: Multi-layered thermoplastic structures comprising a layer of a vinyl or vinylidene fluoride polymer bonded to a layer of an alpha-olefin polymer with the joint aid of a vinyl acetate polymer and a copolymer of ethylene and vinyl acetate.The multi-layered thermoplastic structures can be in the form of films, sheets, plates or tubes which can be used in the field of protection from corrosion or ultra-violet rays.

Abstract: Pharmaceutical compositions containing 3-hydroxybutanoic acid or a salt derived from this acid, such as a sodium salt or alternatively a salt derived from an organic nitrogen base such as an amine; the amine can be an aminoacid of natural origin, such as arginine.The compositions and the compounds according to the invention can be used for the prophylactic and curative treatment of cardiomyopathy of non-ischaemic and ischaemic origin.

Abstract: The polysubstituted dienes according to the invention correspond to the general formula: ##STR1## in which: X denotes a group chosen from the groups SH, SR.sup.3, OR.sup.3, SeR.sup.3, NHR.sup.3 and N.dbd.R.sup.3 in which R.sup.3 denotes an aliphatic or cyclic, saturated or unsaturated group containing from 1 to 20 carbon atoms,Y denotes a group chosen from the groups C.tbd.N and ##STR2## where R.sup.4 denotes hydrogen or an aliphatic or cyclic, saturated or unsaturated group containing from 1 to 20 carbon atoms, provided that, when X denotes the group SCH.sub.3, Y does not denote the group ##STR3## and, when X denotes an OR.sup.3 group where R.sup.3 is an alkyl group containing at least three carbon atoms, Y does not denote the group C.tbd.N,R.sup.1 denotes hydrogen, halogen or an aliphatic, substituted or unsubstituted group containing from 2 to 8 carbon atoms,R.sup.

Abstract: 2,2,2-Trifluoroethanol is obtained by catalytic oxidation of 1,1-difluoroethylene.The 2,2,2-trifluoroethanol thus obtained is used as a solvent or as a synthesis intermediate.

Abstract: Process for the polymerization, in an aqueous suspending medium, of vinylidene fluoride with the aid of an oil-soluble free radical polymerization initiator in the presence of a suspending agent and a chain regulator chosen from the bis(alkyl) carbonates, the alkyl groupings of which contain not more that five carbon atoms wherein the molecular weight of vinylidene fluoride polymers are effectively regulated without having a detrimental effect on the polymerization yield, thus the vinylidene fluoride polymers have a good stability to heat.

Abstract: A portion of a plastic tube (16) heated to a temperature at which stretching induces a molecular orientation, is clamped in a sleeve (14), a fluid under pressure is introduced into the portion of tube and the sleeve is moved along the portion of tube to cause its progressive radial expansion until it makes contact with a mould (1).

Abstract: The film (11) extruded from a vinylidene fluoride polymer is subjected to a stretching of at least 200% while still in the molten state, and then cooled rapidly to a temperature below 50.degree. C.The equipment comprises, in series, an extruding device (1) (2), a cooling device consisting of a thermostatically controlled liquid bath (6), the level of which is located at a distance of 10 to 300 mm from the extruding device, and a device (8) (9) for stretching the extruded film by at least 200% in its part located between the extruding device and the cooling device.The film obtained is suitable for manufacturing piezoelectric films.

Abstract: Moulding composition comprising a vinylidene fluoride polymer and a blowing agent which is a hydroxycarboxylic acid or an alkali metal salt derived from one of the acids.

Abstract: The invention relates to a process for inhibiting the corrosion of an installation, made of a material chosen from amongst the metals which are less noble than hydrogen, and their alloys, in contact with an acid bath containing an alkylpyridinium chloride.A soluble cyanide complex, which is capable of forming an insoluble compound by reacting with ferric ions in the bath, is added to the bath so as to limit the concentration of the ferric ions in the bath to a maximum of 30 mg/kg. The content of ferric ions in the bath is controlled by means of a potentiometric measurement so as to bring the potential of the bath into the region of a predetermined value.The invention applies in particular to the treatment of baths for cleaning or descaling steel installations.