Abstract: A process for preparing polyacetals having less than 10% by weight carbonyl containing units and in which the molar ratio of acetal to furan units is greater than or equal to 15:1 is provided. The process comprises reacting a linear alternating polymer of carbon monoxide with one or more olefins (polyketone) with a diol at elevated temperature in the presence of an acid e.g. para-toluenesulphonic acid while continuously removing water generated by the reaction. Water is preferably removed by azeotropic distillation using a water-immiscible solvent.

Abstract: A slurry of oil-impregnated cuttings from the use of oil based drilling mud and other unwanted slurries and fluids may be injected into the annulus of a sub-sea well and then into a porous formation through which the well has passed using apparatus on a guide base surrounding the sub-sea well head. The guide base comprises a coupling for a pipe extending down from the drilling rig, a one-way isolation valve and pipework leading to the outermost housing of the well. The outermost housing has ports to carry the slurry into the outermost annulus and inner housings may also have ports to carry this slurry into inner annuli. Inter housings also have a one-way check valve to control the injection. The guide base may have a cement circulation pipework and a cement and dump valve. The guide base may also be a retrievable base so that the injection apparatus may be reused.

Abstract: A method of separating metals from carbon-supported catalyst materials comprises the steps of combusting the carbon at a temperature insufficient to cause volatisation of the metal followed by reduction with hydrogen of any oxidised metal and washing with acid or water.

Abstract: A nitrogen-containing polymer is prepared by reacting ammonia or an amine selected from C.sub.1 to C.sub.50 primary alkylamines, benzylamine and substituted benzylamines with a linear terpolymer comprised of alternating --CO-- and --(A)-- units, the --(A)-- units comprising a mixture of --CH.sub.2 CH.sub.2 -- units and --CH.sub.2 CH(R)-- units wherein R is C.sub.1 to C.sub.6 alkyl or phenyl.

Abstract: A mechanical actuator operated by electrical power suitable for actuating down hole equipment in a well, e.g. down hole safety valves, has an electric motor, a gear assembly with a mechanical advantage of at least 30:1, a two-part drive sleeve, the parts being connected by, e.g. splines so that the two parts can rotate together while capable of relative axial movement, an actuating sleeve moved axially by rotation of the drive sleeve, and a releasable lock operated by a solenoid to lock the two parts of the drive sleeve against relative axial movement. Rotation of the motor in one direction primes the actuator, rotating in the other direction actuates the equipment and the solenoid-operated releasable lock holds the equipment in the actuating position. If the solenoid is switched off, deliberately or by power failure, the lock is released allowing the equipment to return to its fail-safe position.

Abstract: A process for preparing single enantiomers of chiral sulphoxides is provided. The process involves (a) reacting an achiral sulphur-containing compound, e.g. a disulphide, with a single enantiomer of a chiral template having the formula T-(CO)-CH.sub.2 R.sup.1, wherein T is suitably (eta.sup.5 -C.sub.5 H.sub.5)Fe(CO)(PPh.sub.3)- (Ph=phenyl) and (b) thereafter stereospecifically oxidizing the sulphur atom with an oxidizing agent. A single enantiomer of the chiral sulphoxide can then be generated by reacting the oxidized product with a carbanion. In a preferred embodiment the reaction mixture is thereafter treated with further achiral sulphide to provide a process which is catalytic on the chiral template.

Abstract: A gauge for measuring bending of structures comprises a bending bar which may be attached to the structure so that it bends in response to bending of the structure and having means for measuring bending of the bar whereby measurement of bending of the bar enables bending of the structure to be determined. Preferably, the bar is hollow with strain gauges on its inner surface and is attached so that at least part of it may move longitudinally along its axis with respect to the structure.

Abstract: A process for treating copper containing precious metal ores prior to cyanidation and recovery of the precious metal eg gold. The process involves addition to the ore before or after milling of a water soluble or water dispersible surface active agent in the form of a fatty alkyl amine preferably an ethoxylated fatty alkyl amine. The agent reduces the high cyanide consumption, which is caused by copper dissolution, by passivating the mineral surface.

Abstract: A process for the preparation of a cogel catalyst comprises preparing an aqueous solution containing a soluble compound of an alkali or alkaline earth metal, a soluble metal compound which is thermally decomposable to a metal oxide capable of converting methane to higher hydrocarbons and a hydrolysable silane under such conditions that a homogenous cogel is formed. The cogel catalyst is effective for oxidizing methane to higher hydrocarbons and exhibits greater selectivity and lasts longer than conventional prior art catalysts. A process for using the cogel catalyst to effect oxidation of methane is also described.

Abstract: A method for the determination of in-line and cross-line components of water velocity relative to a vessel heading on a chosen line, which method comprises the steps of:(a) generating electronic pulses and relaying these to a Doppler-Sonar transducer aligned fore and aft with respect to the keel of the vessel,(b) radiating pulses from the Doppler-Sonar transducer in a number of directions at an angle .theta. relative to the horizontal to a layer of water below but near to the surface of the water, and, simultaneously,(c) radiating pulses from the Doppler-Sonar transducer in a number of directions at an angle .alpha. relative to the horizontal, and greater than .theta.

Abstract: A fail safe annulus valve for fluids has a valve area across the annulus with inlet and exit ports and a slide valve in the area capable of sliding to open or close the ports. The slide valve is biased to its fail safe position by a spring, is susceptible to being opened by independent pressure apparatus, and is also susceptible to movement by differential annulus fluid pressure across the valve. Thus while it fails safe, it can always be moved by differential annulus pressure. The valve may be used for the annuli of oil or gas wells (e.g. annuli used for artificial lift) and may be mounted on a packer of the annulus. It may also be used for closing other types of annuli.

Abstract: A process for depositing a silicon carbide coating on a filament, which comprises heating the filament in a deposition chamber containing a gaseous atmosphere which on contact with the hot filament deposits a coating of silicon carbide; characterized in that the atmosphere in the deposition chamber includes a minor amount of carbon dioxide.

Abstract: A crystalline material having, in the dehydrated form, the empirical formula:m(M.sub.2/a O):X.sub.z O.sub.xz/2 :.sub.y YO.sub.2 (I)in which m is 0.5 to 1.5; M is a cation of valency a; X is a metal of valency x, selected from aluminium, boron, gallium, zinc, iron and titanium; z is 2 when x is an odd number, and z is 1 when x is an even number; y is at least 5; and Y is silicon or germanium; and having, in the calcined hydrogen form, an X-ray diffraction pattern including significant peaks substantially as shown in Table I herein. The material has been designated SUZ-2, and is used in the conversion of hydrocarbons or oxygenates.

Abstract: A corrosion-inhibiting composition comprises a blend of particles of two amorphous silicas; one containing corrosion-inhibiting cations releasable by ion-exchange and the second being substantially free of any corrosion-inhibiting ions. The weight ratio of the cation-containing silica to non ion containing silica is in the range 20:80 to 60:40.The corrosion-inhibiting composition may be incorporated into liquid media and protective coatings, which are based on film-forming polymers e.g. epoxy resins, vinyl resins, epoxy esters.The amorphous silica used is preferably of a microporous type. Calcium cations are the preferred corrosion inhibiting cations. The composition is preferable used to inhibit corrosion of aluminium surfaces.

Abstract: A method for the determination of the value of a property of the material within a mill during the comminution of solid material within the mill comprises the steps of:(a) detecting the noise intensity of milling by means of an analog electrical signal, the intensity of which is proportional to the intensity of the noise in the audio frequency range,(b) converting the analog signal to a digital signal,(c) passing the digital signal through a digital band-pass filter to select at least two frequency bands, and(d) analyzing the data from the bands by means of a multivariate statistical technique to obtain the value of the property. The method is particularly suitable for determining the particle size distribution of material being ground in a ball mill.

Abstract: A method for reducing the tendency of a surface of a material to foul when exposed to a potential foulant comprises the step of treating the surface of the material with a plasma of a compound containing or generating hydroxyl groups to render the surface hydrophylic but substantially uncharged.The materials may be inorganic, e.g. glass, or organic, e.g. polyamide, and may be in the form of fibers, woven fabrics, membranes or plates. Suitable compounds containing hydroxyl groups include ethylene glycol and water.

Abstract: A process for preparing interpolymers of an olefin(s) and carbon monoxide (polyketones) is provided. The process employs a palladium catalyst prepared by reacting together a palladium source, a bidentate amine, phosphine, arsine or stibine and a source of a borate anion. The catalyst effects fast polymerization of the olefin(s) and carbon monoxide in, e.g. methanol or ethoxyethanol solvent. By using the catalyst a lower catalyst deactivation on recycle is observed relative to previously described systems.

Abstract: Hydrocarbyl formates, convertible by hydrolysis into formic acid, are produced by reacting carbon dioxide and hydrogen with a compound of formula ROH wherein R is a hydrocarbyl group in the presence of a substantially insoluble compound of an element selected from Groups III to VIII of the Periodic Table, which element exhibits amphoteric or basic properties, and as catalyst a compound of a transition metal of Group VIa, VIIa or VIII of the Periodic Table, particularly rhodium, ruthenium or iridium.

Abstract: A subsea oil and/or gas production system comprises a template having a three-dimensional framework enclosing one or more production bays, each bay having a well slot and a manifold slot. The space above the well slot is occupied by a tree module fitted with a high pressure cap. The space above the manifold slot is occupied by a manifold header module positioned on the template and forming the base of the equipment in the area of the manifold slot(s), isolation valve module(s) positioned adjacent to the manifold header module and connected thereto, flow control modules(s) positioned adjacent to the isolation valve module(s) and connected thereto, production choke module(s) positioned adjacent to the flow control module(s) and connected thereto, and production control pod(s) positioned adjacent to the flow control modules(s) and connected thereto. The tree module(s) are connected to the flow control module(s).

Abstract: A C.sub.2 and higher hydrocarbon product including ethylene is produced from a methane-containing gaseous paraffinic hydrocarbon feedstock by a process comprising heating the feedstock admixed with oxygen in an amount of at least 5% mol under elevated pressure in a pre-heating zone to a temperature sufficient to cause spontaneous reaction, the pre-heating and mixing being effected in a manner such that (i) substantial oxygen consumption is avoided, and (ii) a "flash-back" of the reaction to form a diffusion flame at the point of gaseous mixing is prevented, and thereafter in a reaction zone allowing the feedstock mixture to spontaneously react.