Abstract: The invention relates to a device for packaging and dispensing a fluid product, having a leaktight flexible pouch (1) placed in a rigid bottle (10) and associated with a pump or a valve (13), this pouch having a cylindrical wall consisting of a sheet (2) rolled into a cylinder, one edge of which is fixed in a leaktight fashion to a flange forming a ring for fastening to the bottle and to the pump or the valve, this flange (4) consisting of a plastic material, the other edge of the said sheet is fixed in a leaktight fashion to a second flange forming the bottom of the pouch, this second flange (3) consisting of a plastic material, these flanges (3, 4) having a solid disk or a ring having a raised edge (3A, 4A) forming an annular lateral surface, to which the edge of the said sheet (2) forming the wall of the pouch is fixed, the said sheet (2) of the cylindrical wall being a multilayer sheet having at least one inner film of plastic material.

Abstract: A method for stiffening a curved sheet-metal panel, in which a flat cardboard panel is applied to the concave face of the curved sheet-metal panel, includes a step in which a number of parallel cuts that pass partially through the thickness of the cardboard panel are made in that face of the cardboard panel that is intended to be applied to the concave face of the sheet-metal panel. A number of adhesive strips that each cover said parallel cuts are applied to said face of the cardboard panel and said face, provided with said adhesive strips, of the cardboard panel is applied to said concave face of the sheet-metal panel.

Abstract: The invention relates to a device for packaging and dispensing a fluid product, having a leaktight flexible pouch (1) placed in a rigid bottle (10) and associated with a pump or a valve (13), this pouch having a cylindrical wall consisting of a sheet (2) rolled into a cylinder, one edge of which is fixed in a leaktight fashion to a flange forming a ring for fastening to the bottle and to the pump or the valve, this flange (4) consisting of a plastic material, the other edge of the said sheet is fixed in a leaktight fashion to a second flange forming the bottom of the pouch, this second flange (3) consisting of a plastic material, these flanges (3, 4) having a solid disk or a ring having a raised edge (3A, 4A) forming an annular lateral surface, to which the edge of the said sheet (2) forming the wall of the pouch is fixed, the said sheet (2) of the cylindrical wall being a multilayer sheet having at least one inner film of plastic material.

Abstract: A device is provided for packaging and dispensing fluid products. The device has a manual pump fitted on a bottle or a pouch containing the product to be dispensed, and has a removable element interposed between the pump and the neck of the bottle. An open/close element is secured to the pump and is able to close the passage circuit for the product to be dispensed between the inside of the bottle and the pump when the removable element is in place.

Abstract: A method for stiffening a curved sheet-metal panel, in which a flat cardboard panel is applied to the concave face of the curved sheet-metal panel, includes a step in which a number of parallel cuts that pass partially through the thickness of the cardboard panel are made in that face of the cardboard panel that is intended to be applied to the concave face of the sheet-metal panel. A number of adhesive strips that each cover said parallel cuts are applied to said face of the cardboard panel and said face, provided with said adhesive strips, of the cardboard panel is applied to said concave face of the sheet-metal panel.

Abstract: The invention relates to a device for packaging and dispensing fluid products. The device, of the type having a manual pump (2) fitted on a bottle (1) or a pouch (5) containing the product to be dispensed, has a removable element (11) interposed between the pump (2) and the neck of the bottle (1), and an open/close element (13) which is secured to the pump (2) and is able to close the passage circuit for the product to be dispensed between the inside of the bottle (1) and the pump (2) when the removable element (11) is in place. Application to improving the preservation on storage of the product contained in the bottle or the pouch.

Abstract: A process in which isotopes of the same element belonging to the alkaline earth metals, transition elements and heavy metals having an atomic mass of less than 209, in particular lanthanide metals, are separated in an aqueous medium by treating an aqueous medium.

Abstract: A process in which isotopes of the same element belonging to the alkaline earth metals, transition elements and heavy metals having an atomic mass of less than 209, in particular lanthanide metals, are separated in an aqueous medium by treating an aqueous medium.

Abstract: A process in which isotopes of the same element belonging to the alkaline earth metals, transition elements and heavy metals having an atomic mass of less than 209, in particular lanthanide metals, are separated in an aqueous medium by treating an aqueous medium.

Abstract: The invention relates to the separation of lanthanides and actinides by nanofiltration complexation. The object of the invention is to satisfy the existing need for a simple, efficient and economical technique for separating lanthanides and actinides. This object is achieved by a process consisting of using ligands of the polyamino acid type, such as EDTA or DTPA, for complexing lanthanides and/or actinides before separating them by nanofiltration. The invention further relates to novel polyamino acid ligands incorporating ligand structures additional to EDTA and DTPA. Application to the production of rare earths or nuclear waste processing, especially to recycling operations carried out on spent nuclear fuels is also discussed.

Abstract: A process in which isotopes of the same element belonging to the alkaline earth metals, transition elements and heavy metals having an atomic mass of less than 209, in particular lanthanide metals, are separated in an aqueous medium by treating an aqueous medium.

Abstract: The invention relates to a process for separating sodium from aqueous effluents resulting from the reprocessing of spent nuclear fuel elements. According to the invention, the effluent (3) is introduced into a tangential filtration module (11), whose membranes are made from polyaramide, sulphonated polysulphone or perfluorinated ionomer, so as to collect a permeate P containing sodium, depleted in radioactive elements and a retentate R enriched in radioactive elements.

Abstract: The invention relates to a process and an installation for the decontamination of radioactive nitric effluents containing strontium and sodium. According to this process, contacting takes place in 1 of the aqueous effluent with an organic phase incorporating a crown ether such as DCH18C6 and a diluent such as CHCl.sub.3, in order to selectively extract the strontium with respect to the sodium, followed by the reextraction of the strontium in an aqueous solution in 3, followed by fixing in 5 on a cation exchange resin. This leads to a high strontium decontamination level with a very high concentration factor.

Abstract: The invention relates to a process fop trapping gaseous ruthenium on polyvinyl pyridine, more particularly usable for recovering radioactive ruthenium from irradiated nuclear fuels.This process consists of contacting a gas containing ruthenium in gaseous form with an adsorbent (11b) constituted by a vinyl pyridine polymer or copolymer for fixing the ruthenium to the latter. The gas can be constituted by yapours from a concentrate of fission products containing ruthenium, which has been heated (at 31) in the presence of an oxidizing agent for volatilizing the ruthenium.

Abstract: The invention relates to a process for the separation of at least one element such as Nb, Sb, Ce+Pr, actinides and elements from groups VIIb and VIII of the Periodic Classification of Elements from aqueous solutions resulting from the reprocessing of spent nuclear fuels.This process consists of contacting said aqueous solution with a solid resin based on a vinyl pyridine polymer or copolymer and separating from said solution the resin used for fixing said element or elements.The resin is in particular a poly(vinyl-4-pyridine) powder in crosslinked from and the separated elements are e.g. ruthenium, rhodium, palladium, technetium, manganese, cobalt, iron, nickel, cerium and praseodymium.

Abstract: The invention concerns the recovery of Pu (IV) by using crown compounds.According to the invention, the aqueous solution containing the plutonium (IV) is placed in contact with at least one crown compound, for example DCH 18C6, dissolved in an organic diluting agent, such as benzonitrile. In the case where the solution only contains traces of Pu, it is possible to use a crown compound secured to a solid phase, such as silica.The aqueous solution is a concentrated solution of fission products, an effluent originating from an irradiated nuclear fuel reprocessing installation or a concentrated solution of plutonium with americium.

Abstract: The invention concerns the recovery of Pu (IV) by using crown compounds.According to the invention, the aqueous solution containing the plutonium (IV) is placed in contact with at least one crown compound, for example DCH 18C6, dissolved in an organic diluting agent, such as benzonitrile. In the case where the solution only contains traces of Pu, it is possible to use a crown compound secured to a solid phase, such as silica.The aqueous solution is a concentrated solution of fission products, an effluent originating from an irradiated nuclear fuel reprocessing installation or a concentrated solution of plutonium with americium.

Abstract: The invention relates to the use of thioether ligands in accordance with the formula: ##STR1## in which R.sup.1 and R.sup.2, which can be the same or different, represent alkyl radicals, R.sup.3 is an alkyl radical and A represents a divalent radical chosen from among the radicals of formula:--(CH.sub.2).sub.m ----(CH.sub.2).sub.n --X--(CH.sub.2).sub.p -- ##STR2## in which m is equal to 0 or is an integer from 1 to 6, n and p are integers between 1 and 6 and X represents O or S, for recovering the palladium present in a nitric aqueous solution (A.sub.0) for dissolving irradiated nuclear fuel elements.For example, it is possible to use the ligand of formula (I) with A representing CH.sub.2 --S--CH.sub.2 and R.sup.1 and R.sup.2 representing C.sub.10 H.sub.21.

Abstract: A method for separating plutonium from uranium and from fission products with the aid of crown ether compounds comprising contacting an aqueous solution A0 containing Pu, U and fission products with an organic solvent O0 containing at least one crown ether compound to obtain an organic solution O1 containing Pu and U; extracting U from the organic solution O1 with an aqueous solution A4 such as water or nitric acid to obtain an aqueous solution A5 containing U and an organic solution O3 containing mainly of Pu and recovering Pu from the organic solution using an aqueous solution A6 such as sulfuric acid.

Abstract: A method for separating the isomers of a crown ether compound and making it possible to recover in particular the pure cis-syn-cis isomer from DCH 18C6 includes:a) dissolving in an organic solvent a mixture of the isomers of said crown compound including the cis-anti-cis isomer and the cis-syn-cis isomer,b) adding uranyl nitrate to the solution obtained in stage a) in sufficient quantities so that virtually all of the isomers, except the cis-syn-cis isomer, are precipitated in the form of complexes with the uranyl nitrate,c) separating the formed precipitate,d) recovering the cis-syn-cis isomer from the solution, ande) recovering the cis-anti-cis isomer from the precipitate.