Abstract: Gas or air filled microbubble suspensions in aqueous phase usable as imaging contrast agents in ultrasonic echography. They contain laminarized surfactants and, optionally, hydrophilic stabilizers. The laminarized surfactants can be in the form of liposomes. The suspensions are obtained by exposing the laminarized surfactants to air or a gas before or after admixing with an aqueous phase.

Abstract: Injectable aqueous composition intended for opacifying certain organs with a view to examination by X-rays. This composition is based on liposomes containing, encapsulated therein, an aqueous solution of an iodinated opacifying agent. The ratio between the weight of iodine encapsulated by the liposomes and the weight of the lipids from which their membrane is formed is not lower than 1.5 mg/mg.

Abstract: The subject of the present invention is a process for treating highly environmentally polluting residues such as for example residues derived from dry or wet filtration. The process consists in mixing the residues with a product containing iron oxide, in placing the mixture in a crucible, in protecting the crucible with insulating fibers, in putting the crucible in a microwave oven and in exposing the mixture to microwaves for a time of between 2 and 15 minutes at a temperature of between 1000.degree. and 1300.degree. C. in order to produce a dry fusion of the mixture and to obtain a solid material. The present invention is applicable to the reclaiming of sludge from the iron and steel industry.

Abstract: Gas or air filled microbubble suspensions in aqueous phases usable as imaging contrast agents in ultrasonic echography. They contain laminarized surfactants and, optionally, hydrophilic stabilizers. The laminarized surfactants can be in the form of liposomes. The suspensions are obtained by exposing the laminarized surfactants to air or a gas before or after admixing with an aqueous phase.

Abstract: Copolymer film deposited on a substrate comprising covalently fixed fragments of heparin having antithrombogenic properties. The polymer further comprises free carboxylic groups intended to neutralize free amine functions which are possibly present and to improve the hemocompatibility of the film.

Abstract: A ligand specific to a bioactive substance to be purified is fixed, via a connecting silane, to a mineral particulate carrier chosen from among SiO.sub.2, Al.sub.2 O.sub.3, ZrO.sub.2 and TiO.sub.2, the particles of the carrier being submicronic, non-porous and having a large specific surface. The carrier is contacted with an aqueous extract containing inter alia the bioactive substances, for the time required for the substance to become specifically fixed to the carrier. The carrier is then separated and the desired bioactive substance is isolated by desorption.

Abstract: A ligand specific to a bioactive substance to be purified is fixed, through a connecting silane, to a mineral particulate carrier chosen from among SiO.sub.2, Al.sub.2 O.sub.3, ZrO.sub.2 and TiO.sub.2, the particles of the carrier being submicronic, non-porous and having a large specific surface. The carrier is contacted with an aqueous extract containing the bioactive substances, for the time required for the substance to become specifically fixed to the carrier. The carrier is then separated and the desired bioactive substance is isolated by desorption.

Abstract: The tuyere comprises a substantially cylindrical or slightly convergent frusto-conical downstream part, and a divergent frusto-conical upstream part; the plasma torch is placed co-axially to the tuyere at the inlet to the upstream part thereof; the solid materials injection nozzle issues at an angle into the upstream part of the tuyere and the angle of taper of the upstream part of the tuyere substantially corresponds to the angle of natural expansion of the plasma jet, so that said materials are carried with the plasma jet and that part of them are provided onto the inner wall of the tuyere.

Abstract: A hydrophilic coating photopolymerizable in air, capable of fixing bioactive molecules is formed from a mixture of acrylic or methacrylic monomers containing at least 20% by weight of an approximately quimolecular mixture of acrylic acid and an N-dialkylated amino-alcohol acrylate or methacrylate.

Abstract: Porous glass beads for filtation applications having a homogeneous metaloxane structure and comprising oxides of Si, Zr and optionally Ti and Al. A preferred method for making these beads comprises the steps of (a) providing a mother solution of Si and Zr alkoxides in a water soluble solvent, for instance a lower aliphatic alcohol, (b) providing a liquid dispersant phase in which solution (a) is dispersible and stirring this liquid phase sufficiently to cause (a) to be formed into droplets of substantially uniform size when added to (b), (c) adding (a) to (b) at a rate sufficient to provide said droplets and effecting the hydrolysis of the alkoxides contained therein with consecutive gelation of said droplets into corresponding hardened beads of condensed mixed Si and Zr hydroxides, and (d) separating said beads from the liquid phase and drying to achieve the desired porous mixed oxide structure for the beads.

Abstract: The invention relates to a device for injecting pulverulent material, such as coal, into a blast furnace. The device includes a hot blast tuyere issuing into the blast furnace, a nozzle fixed against said tuyere and co-axial thereto for bringing the hot blast, a branch connection produced obliquely on the nozzle and directed towards the tuyere, and an injection pipe traversing the branch connection to issue into the tuyere. According to the invention, the injection pipe is substantially an arc of circle, the convexity of which is directed towards the axis of the nozzle and of the tuyere. The radius of curvature is at least equal to one hundred times its inner diameter.

Abstract: An acrylic-acid- based photopolymerizable composition is prepared which is capable of binding bioactive substances after being photopolymerized. The composition may be applied as a coating on a carrier substrate, photopolymerized and a bioactive substance fixed thereto. The composition adheres well to any usual carrier substrates, and its degree of hydrophilicity and permeability can be adapted to needs. The composition contains acrylic acid, a photoinitiator which is an aromatic ketone compound, a photopolymerization activator and adhesion promotor which is an amino-alcohol, acrylate or methacrylate, and a copolymerizable olefinic monomer which contains a reactive functional group capable of binding bioactive substances. The olefinic monomer is preferably N-hydroxysuccinimide acrylate, N-hydroxysuccinninimde amidocaproate, epoxypropyl acrylate or 2-isocyanato-ethyl acrylate.

Abstract: There is described a process for the production of a polysaccharide-producing enzyme, which comprises fermenting an appropriate enzyme producing organism in aqueous sucrose, characterized in that the sucrose concentration is maintained at between 1 and 10 g/l throughout all but the last part of the fermentation and that the dissolved oxygen content of the fermentation is controlled.There is also described a method for the purification of a polysaccharide producing enzyme, which comprises absorbing a mixture containing the enzyme on an anionic resin and removing the enzyme from the resin with a sugar containing eluant, and a novel highly purified form of polysaccharide producing enzyme.

Abstract: The invention concerns a process for the dehydration of a colloidal dispersion of liposomes in an aqueous liquid medium, this process being aimed at extending the conservation of the liposomes and to enable their efficient use at a later date.According to this process, there is prepared a mixture of a hydrophilic compound and the liposome dispersion. This mixture is then subjected to a dehydration operation leading to the formation of liposomes in the form of a stable powder which can be stored for a long period and from which a dispersion of liposomes can be reconstituted.

Abstract: A process for the preparation of a solution or suspension of liposomes in an aqueous medium comprising the steps of dispersing a first aqueous liquid in an essentially water-insoluble solvent in the presence of a compound of the formula XY wherein X is a hydrophilic lipophobic group and Y is a lipophilic hydrophobic group to form a dispersion of liposome precursors in the solvent, the precursors consisting of small vesicles of the first aqueous liquid surrounded by a monomolecular film of compound XY, emulsifying the liposome precursors in a second aqueous medium in the presence of a compound of the formula ZW wherein Z is a hydrophilic group and W is a hydrophobic group to thereby form a solution or suspension of liposomes in the second aqueous medium, said liposomes consisting of the first aqueous liquid surrounded by a bimolecular film of the structure XY-WZ and removing the water-insoluble solvent prior to after said emulsification.

Abstract: Synthetic liposomes, for example containing a biologically active substance, are prepared by dispersing a first aqueous liquid with the aid of ultrasonic vibration in a water-immiscible carrier liquid less dense than water in the presence of a compound of the formula XY where X is a hydrophilic polar group and Y is a hydrophobic non-polar group to form dispersed globules of the first aqueous liquid each bounded by a monomolecular layer of the compound XY; adding this dispersion to a second aqueous liquid to form a two layer system separated and bounded by a monomolecular second layer of the compound XY and then centrifuging the system to force the dispersed globules through the second boundary layer of the compound XY and into the second aqueous liquid.

Abstract: A process for using and preparing a reversibly soluble enzymatically active polymer enzyme product which consists of an enzyme covalently bonded to a water soluble organic polymer selected from polyacrylic acid, dextran, carboxy methyl cellulose, and polyethylene glycol which have carboxyl or amino side groups that impart to the complex its reversible solubility.

Abstract: A polypeptide is extracted from an aqueous solution by a process in which a water-soluble macromolecular complex (I) of macromolecules covalently boned to molecules of at least one compound capable of fixing the polypeptide in a selective, reversible and non-destructive manner, is selectively reacted with the polypeptide in the solution to fix the polypeptide by forming in solution a complex (II); and the complex (II) is separated from the solution and dissociated into polypeptide molecules and complex (I) molecules, and the polypeptide is isolated.