Abstract: Process for recovering a polymer by injection of steam, and optionally liquid water, into a solution of this polymer comprising a polar aprotic organic solvent (PAOS) that has an azeotrope with water and an apolar organic compound that is miscible with the PAOS and immiscible with water and that acts as a phase separation agent (PSA), the boiling point of which is below that of the water/PAOS azeotrope, the amount of steam injected being sufficient to give rise to the substantial removal of the PSA via stripping and that of the PAOS via azeotropic distillation, and the total amount of water being sufficient to give rise to the precipitation of the polymer, this process being characterized in that the polymer solution also comprises an alcohol, at least during the precipitation of the polymer.

Abstract: The disclosure relates to a method for oxidising one or more organic compounds, including placing the organic compounds in contact with at least one oxidising agent as well as with a catalyst agent including at least one source of divalent or trivalent transition metal ions and at least one poly-?-hydroxyacrylic acid and/or a poly-?-hydroxyacrylate. The disclosure can be used for removing pollutants from soils.

Abstract: The present invention relates to the in situ and ex situ oxidation of organic compounds in soils, sludges, ground-water, process water and wastewater and especially relates to the in situ oxidation of volatile and semi-volatile organic compounds, pesticides and herbicides, and other recalcitrant organic compounds, in soil and groundwater using percarbonate activated persulfate.

Abstract: Electrodialysis device endbox comprising a vertical electrode (7) and a selectively ion-permeable membrane (10) which is arranged vertically, facing the electrode, and separated from the latter by a vertical passage (19) Electrodialysis device comprising an alternation of selectively ion permeable vertical membranes (1, 2, 3) and dividers (4) between two endboxes (5), at least one of which is as defined hereinabove.

Abstract: Reinforced pipe obtained by winding, onto a tubular support based on a polymeric composition, of reinforcing tapes comprising an oriented polymeric composition in layers crossed at an equal but opposite angle relative to the axis of the pipe. The tapes are selected from those whose polymeric composition exhibits particular mechanical strength properties in tension.

Abstract: Process for manufacturing an oxirane in a reactor containing a liquid reaction medium, according to which an olefin is reacted, in a liquid reaction medium, with a peroxide compound in the presence of a solvent and in the presence of a solid catalyst which is used in the form of particles, at least some of which are in fluidized form in the reactor.

Abstract: The invention relates to a novel sodium percarbonate in the form of agglomerates of small crystals. The average particle size of the agglomerates is greater than 600 &mgr;m. The apparent density of the agglomerates is between 0.75 g/cm3 and 1.1 g/cm3, and the active oxygen is greater than 14%. The invention also relates to a process for the continuous manufacture of sodium percarbonate in a fluidized bed.

Abstract: System for the venting of a liquid tank, comprising a float valve, arranged in the tank, in communication with a pipe forming one end of a venting circuit, and a closed volume internal to the tank and provided with an emptying device, the closed volume functioning as a capacity intended for collecting any possible entrainments of liquid coming from the tank, the valve being located outside the volume of the capacity and being connected to the latter by means of the pipe of the venting circuit.

Abstract: The invention relates to a fuel tank produced by moulding a synthetic resin, comprising a breather orifice and a chamber that is intended to contain a substance that adsorbs the fuel vapors. The said chamber has at least one wall portion that is common, and formed integrally by moulding, with a portion of the wall of the tank.

Abstract: The dialkyl peroxydicarbonates with short alkyl chains, are used for the aqueous suspension polymerization of vinyl chloride, in the form of a solution in a dialkyl alkanedicarboxylate. The preferred solvents are hexanedicarboxylates (adipates) derived from adipic acid and C6-C10 alkanols. The peroxydicarbonate concentration of the said solutions is generally 15-40% by weight. The process according to the invention produces vinyl chloride polymers of improved quality resulting in shaped articles exhibiting markedly fewer fisheyes. The invention also relates to a two-stage process for the manufacture of a solution of dialkyl peroxydicarbonates with short alkyl chains which is particularly suited for the aqueous suspension polymerization of vinyl chloride. According to this process an inorganic salt is used in the stage of manufacture of the peroxydicarbonate (first stage) and the latter is subsequently isolated by extraction by means of a water-insoluble solvent (second stage).

Abstract: In the invention pickling process, steel and nickel or chromium alloys are pickled with an acidic pickling solution employing an oxidant, particularly hydrogen peroxide, and in which liquor is recirculated through inlets comprising a nozzle feeding liquor into a diffuser such that liquor is withdrawn from the bath and the volume of liquor flowing through the diffuser is a multiple of flow through the nozzle. Steel or the alloys are pickled with an acidic solution containing iron and free hydrogen peroxide at a concentration of up to 0.1 gpl. The process can operate effectively at a free fluoride concentration of from 20 to 30 gpl and a sulphuric acid concentration of from 80 to 110 gpl. The lifetime of the bath before it needs to be replaced can be lengthened by the process compared with using an air agitation system.

Abstract: Shut-off device for progressive regulation of the flow rate of a fluid flowing in a pipe (1), comprising(a) a main shut-off member (3) able to pivot independently about a spindle (4) passing through the pipe and close the latter, and(b) at least one drive flap (5) able to pivot about the spindle (4) and act mechanically on the main shut-off member (3) in such a way as to turn it about the spindle (4); the main shut-off member (3) also being traversed by at least one orifice (6) that can be closed by at least one shut-off flap, which flap can also pivot about the spindle (4), is integral with the drive flap (5) and can regulate the rate of flow of the fluid through the orifice; the main shut-off member (3) only beginning to pivot about the spindle (4), from an initial closed position, when the drive flap (5) is at a predetermined non-zero angular distance .o slashed. from the said member, thus allowing the fluid to flow only through the orifice (6) until the main shut-off member (3) begins to open.

Abstract: Compounds having the general formula: ##STR1## in which R3 represents an aryl group which is unsubstituted or substituted by one or more alkyl groups containing 1 to 4 carbon atoms; R4 represents a hydrogen atom, a group for protecting the amino functional group, an amino acid or a peptide some of whose functional groups are optionally substituted by a protecting group or by an activating group; R5 represents a hydroxy group, a halogen atom, a group for protecting the carboxyl functional group, an activating group, an amino group, an amino acid or a peptide some of whose functional groups are optionally substituted by a protecting group or by an activating group; and n is an integer from 1 to 10.

Abstract: Process for converting a chlorinated alkane into at least one less chlorinated alkene by reaction with hydrogen in the presence of a catalyst comprising palladium and a metal selected from the group consisting of silver, gallium, indium, thallium, germanium, tin, lead, arsenic, antimony, bismuth and mixtures thereof.

Abstract: The invention relates to a process for the work-up of a liquid complex hydrofluoride of a tertiary amine of the formula (I) ?R.sup.1 R.sup.2 R.sup.3 N.multidot.n HF!, where the radicals R.sup.1, R.sup.2 and R.sup.3 are C.sub.1 -C.sub.8 -alkyl groups which together have at least 7 carbon atoms and n is an integer or fractional number where 1.5<n<3, which, for the purpose of molecular addition of HF to a halogenated alkene, is reacted with the latter. In the reaction of the halogenated alkene with the complex amine hydrofluoride of the formula (I), the molar ratio HF:R.sup.1 R.sup.2 R.sup.3 N is allowed to fall until amine separates out as a further liquid phase, and the amine is separated off.

Abstract: Difluoromethane is produced by reaction, in the liquid phase, between dichloromethane and hydrogen fluoride, in the presence of a titanium or tin halide.

Abstract: The invention relates to the preparation of trifluoroacetyl fluoride by reacting trichloroacetyl chloride with anhydrous hydrogen fluoride in the gaseous phase on a catalyst which is obtainable by reacting a water-soluble chromium (III) salt with magnesium hydroxide or magnesium oxide in the presence of water, converting the reaction mixture into a paste, drying the paste and treating it with hydrogen fluoride.

Abstract: Process for manufacturing a composite article comprising a solid body reinforced by winding at least one reinforcing tape around the solid body. The reinforcing tape deposited on the solid body is subjected to a constant tensile force. Downstream of the point where it comes into contact with the solid body, this reinforcing tape is consolidated by a local pressure. The invention also relates to a device for the manufacture of such reinforced composite articles.

Abstract: End casing for an electrodialyzer, comprising a vertical panel (8) and a vertical frame (9) which define between them a cavity containing an electrode, the said electrode comprising a perforated vertical metal plate (12) which is arranged in the cavity, facing the panel and set back therefrom, so as to form a chamber (21) between the panel, the plate and the frame, the said chamber being divided into vertical channels (27, 28) by vertical partitions (29) and being in communication with an inlet conduit (23, 26) and a discharge conduit (22, 24) for electrolytes. Electrodialyzer comprising an alternating succession of selectively ion-permeable membranes (1, 1', 25, 25') and vertical frames (2) between two end casings (3, 3') as defined above.

Abstract: The present invention relates to a material for semiconductive screening and to use of the material in manufacturing cables and capacitors, and in electromagnetic shielding of electrical and electronic apparatus. The present invention further relates to cables and electrical and electronic apparatus containing the material. The semiconductive screening is formed of a polymer matrix containing one or more polymers and in which matrix 5% to 70% (by weight) of at least one conjugated non-doped or dedoped polymer is to be found in the dispersed state. In the absence of an electric field, the conductivity of the screening is very low, but said conductivity is an increasing function of the applied field (see curves 2 to 9 in the figure).