Compound having the formula wherein X is the residue of a polyoxyalkylene diamine or triamine having an average equivalent weight of at least 500, after having deleted the two or three amine groups, n is two if X is a residue of a diamine and three if X is a residue of a triamine, and R is the residue of a cyclic anhydride of a polycarboxylic acid having at least four carboxyl groups, afte...

A process for synthesizing 3-O- beta -D-Galactopyranosyl-2-acetamido-2-deoxy-galactose (1) by enzymatic transgalactosylation using beta -galactosidases, characterized by the steps: a) transgalactosylating a substrate mixture of lactose and 2-acetamido-2-deoxy-D-galactose utilizing the transgalactolytic activity possessed by beta -galactosidase of mammalian origin to form an olgiosaccharide mix...

A process for synthesizing 3-O- beta -D-Galactopyranosyl-2-acetamido-2-deoxy-galactose (1) by enzymatic transgalactosylation using beta -galactosidases, characterized by the steps: a) transgalactosylating a substrate mixture of lactose and 2-acetamido-2-deoxy-D-galactose utilizing the transgalactolytic activity possessed by beta -galactosidase of mammalian origin to form an olgiosaccharide mix...

A method of welding at least two layers (18, 20) of thermoplastic material, e.g. polyethylene terephthalate or polyporopylene, and a weld (30) so produced comprises directing a jet of hot gas from a nozzle (10), through a hole (16) in an inlet mask (16), and against the layers (18, 20). The layers (18, 20) are backed by an outlet mask (22) having a hole (26) and serving as a heat sink. The inlet m...

A method of welding at least two layers (18, 20) of thermoplastic material, e.g. polyethylene terephthalate or polyporopylene, and a weld (30) so produced comprises directing a jet of hot gas from a nozzle (10), through a hole (16) in an inlet mask (16), and against the layers (18, 20). The layers (18, 20) are backed by an outlet mask (22) having a hole (26) and serving as a heat sink. The inlet m...

When used as occlusion agents or to cause fractures in a petroleum reservoir, polymer gels crosslinked with polyvalent metal ions can be removed by the use of special complexing agents.

An automotive seat with a heating device provided therein, in which a trim cover assembly is integrally affixed over a foam cushion member, comprises a recessed portion formed at the rear of the cushion member, a block member removably inserted in the recessed portion, and a heating device secured on the block member. With such structure, the heating device is embedded in the cushion member such t...

Nuclear fuel elements for use in the core of a nuclear reactor include an improved composite cladding (17) having a zirconium barrier layer (22) metallurgically bonded on the inside surface of a zirconium alloy tube (21), wherein the inside surface of the barrier is alloyed with preselected elemental impurities to improve oxidation resistance. The zirconium barrier layer (22) forms a shield betwee...

The rotor (2) has three radially projecting arms, each with its own work unit (22, 23). These units each comprise a diamond rod (22) for milling away the floot lining when the rotor rotates, and a retainer (23) positioned in front of the diamond rod, and which slides against the floor lining to hold it in place during the milling process.

A concrete made of a mixture of slag cement and Portland cement has a greater resistance, in an acid environment and in a saline environment, than pure Portland cement. Its resistance is further increased by addition of iron oxide.

The boat comprises a water cushion, with parts which can be pressed downwards to form a multi-part keel.