Abstract: A portable diagnostic system for testing gas pressure reduction equipment includes a computer arrangement 16 interfaced to an electro-pneumatic test unit 12 which provides test pressures for and receives information on displacement from the pressure reduction equipment. Unit 12 includes a number of valves including three solenoid on/off valves, a needle valve and an on/off ball valve. The position of the valve member of the needle valve is sensed by a position transducer. Displacement transducers 40 and 42 connected to the reduction equipment sense slamshut valve and regulator displacements pressure transducer 44 and a differential pressure transducer 102 are each connected to the equipment. Signals from the transducers are fed to a data acquisition system 210 which also drives the solenoid valves and the needle and ball valves, all under the control of the PC16 to give an indication for example of how far the valves are open in the regulating equipment (ie from the valve seat).

Abstract: A plate valve which includes two sliding plates and which carries seal portions with an elongated slot. A valve body of the plate valve includes a second elongated slot with further seal portions extending from a valve aperture. A cable of different diameters can be accommodated and sealed by the cooperating resilient seal portions.

Abstract: An iron cyanide complex is biodegraded by growing a fungus selected from Fusarium solani, Trichoderma polysporum, Penicillium miczynski, Fusarium oxysporum, and Scytalidium thermophilum in a medium containing the iron cyanide complex.

Abstract: Apparatus for providing an offshore drilling operation in a sea, the apparatus comprising a drilling derrick support structure (2) having a base (4) to rest on the sea-floor (5) and a deck (7) to support a drilling derrick (1), the structure being in the form of a concrete block (2) having a hollow cavity to enable the block (2) to be floated to the site where drilling is to take place and being adapted to receive ballast into the cavity in such a way and in a sufficient quantity as to cause the block (2) to sink base-first and rest upon the sea-bed with the deck (7) clear of the surface of the sea, a drilling derrick (1) for mounting on the deck (7) of the block (2) and a tender assist barge (3) for transport to the site in down to 2 m of water to provide services, supplies and equipment to the drilling derrick (1).

Abstract: A seismic pulse generator (1) has a chamber (4) pressurised with gas. The generator includes a solenoid valve (60) which can be actuated to cause the release to atmosphere of only a small amount of pressurised gas from a small control chamber (34) behind a main piston (30) to enable the piston to move away from a valve seat (32) around an outlet (26). This permits the abrupt release of the pressurised gas in the chamber (4) through the outlet and the “firing” of the generator. The arrangement maximises the use of the main pressurised gas for actual “firing” of the generator.

Abstract: A heat exchanger formed of two plates or stages with one being on top of the other and with a plurality of such heat exchangers stacked on each other. The first stage has an inlet opening, an inlet passage and passages opened to the end of the stage. The second stage has an inlet opening leading to passages which lead to an outlet passage and an outlet opening. The second stage also has an inlet opening leading to passages which have an outlet at the end. A combustible gas enters the passage region of the first stage where the mixture is preheated and then passes to a passage region of the first stage. Portions of the gas passages in the passage region contain a combustion promoting catalyst so that the gas burns in the passage region. The products of combustion leave through the outlet end and are conveyed to an inlet of the passage region of the second stage.

Abstract: A method of electrochemistry is conducted by conducting the direct electrochemistry of a monooxygenase enzyme in the absence of mediators. A method of electrochemistry is conducted by conducting the direct electrochemistry of an hydroxylase enzyme in the absence of mediators.

Abstract: A fluid testing arrangement includes an adaptor/connector 16 which couples to a service pipe 11 to allow fluid passage to continue from the main pipe 10. A catheter 18 is passed through the supplementary connection 17 and through the bore of the adaptor into the service pipe 11 until it reaches the main pipe tee connector 12. A logger 20 senses and measures the fluid pressure in effect, at the main pipe without the need to excavate.

Abstract: A steel service pipe is connected to a main by a tee. A flexible assembly is inserted through the open end of the pipe and through the tee into the main. The flexible assembly includes a section of lower stiffness and a ball and socket connection of even lower stiffness at its leading end. The ball is connected to a weight. The weight falls down on entering the tee and creates a turning moment on the assembly. A plastic pipe is inserted through the open end of the pipe over the assembly and is inserted through the tee into the main. The pipe has a corrugated leading end which is more flexible than the remainder of the pipe and has a tapered nose terminating in a cylindrical mouth which enters an aperture in a liner in the main.

Abstract: A method for permitting the joining together of two adjacent pipe lengths with adjacent ends curving with substantially the same sense, the method comprising rotating the end of one of the pipe lengths about its axis until it curves in substantially the opposite sense to the curve of the adjacent end of the other pipe length.

Abstract: A method and apparatus for testing a fluid conduit system for leaks. The apparatus is connected to an isolated section of a domestic fuel gas system which is suspected of leaking. The apparatus determines over recorded time periods the pressure drop in the system as a result of the actual gas leak and subsequently the pressure drop in the system as a result of an actual leak plus the leakage through an introduced artificial and calibrated orifice provided by the apparatus. The data is used in an equation for calculating the actual leakage rate from the system. This method avoids the need to repressurize the system between pressure drop measurements or having to know or assume the volume of the system being tested.

Abstract: A mutant of the mono-oxygenase cytochrome P450cam in which the cysteine residue at position 334 is removed.

Abstract: An electric power generation system using fuel cells, wherein the system includes a stack of fuel cells each having an anode, electrolyte and a cathode. Associated with the anodes are anode passageways divided into two groups. Each group is formed by anode passageways connected to one of the two anode gas exhaust manifolds. Associated with the cathodes are cathode passageways divided into two groups. Each group is formed by cathode passageways connected to one of the two cathode gas exhaust manifolds. The anode exhaust gas in each of the manifolds is maintained completely separate from that in the other manifold. Similarly, the cathode exhaust gas is separate in the two manifolds. Fuel gas from a supply is fed to an inlet manifold supplying all of the anode passageways in which the reforming reaction takes place. Anode exhaust gas from the outer manifold is supplied to the inlet manifold to mix with the fuel gas to the anode passageways.

Abstract: A process for producing natural gas hydrate comprises three states (i), (ii), and (iii). State (i) comprises three pressure vessels (A1, A2, and A3), stage (ii) two pressure vessels (A4 and A5), and stage (iii) the pressure vessel (A6). The conditions of temperature and pressure in the pressure vessels are such that the gas hydrate is formed in the vessels. The formed hydrate is taken off through pipes (e1, e2, e3, e4, e5, and e6) from the pressure vessels to a manifold (34). Chilled water which is both the reactant water and coolant for the process is provided by cooling means (20) and supplied simultaneously to the lower part of each pressure vessel via pipe (22), manifold (32) and pipes (b1, b2, b4, b5, and b6). Natural gas from supply (26) is fed via pipe (30), manifold (32) and pipes (c1, c2, and c3) to nozzles in the lower part of each vessel (A1, A2, and A3) from which nozzles the gas bubbles upwards through the columns of water in vessels (A1, A2, and A3).

Abstract: A replacement pipe is installed within an existing service pipe (1) by first advancing a sealing means (6,8) along the existing pipe to a position adjacent its junction with a main pipe (2), then deploying the sealing means to seal against the inner surface of the existing pipe) in the example shown, by pumping sealant (10) into the space between the seal body (6) and the pipe (1), and subsequently advancing the replacement pipe along the existing pipe. The space between the two pipes is then filled with sealant and finally the sealing means is opened, in the example shown by withdrawing a guide rod (5) and its collar (7) on which the sealing means was advanced into position.

Abstract: A mutant of the mono-oxygenase cytochrome P-450.sub.cam in which the tyrosine residue at position 96 and/or the cysteine residue at positon 334 is replaced by the residue of any amino acid except phenylalanine.

Abstract: A flexible probe for insertion into an auxiliary pipe indicates the proximity of the auxiliary pipe to a device within a main pipe. The probe includes an apparatus for generating a magnetic field for detection within the main pipe. An indicator associated with the probe generates a signal when the probe is adjacent the main pipe. The magnetic field generating apparatus includes a coil with an electronic circuit for generating an alternating current signal and also includes a switch operable when the probe contacts the main pipe.

Abstract: A electrochemical power generation system comprising a plurality of fuel cells electrically connected to each other, each fuel cell having an anode and a cathode. A plurality of first passage means are associated with and defined by the anodes and a plurality of second passages means are associated with and defined by the cathodes. The first passage means is divided into a first group and a second group of passage means. A third passage means is connected to the inlets of the first group to supply fuel gas to the first group. A fourth passage means receives the anode exhaust gas from the first group. The fourth passage means is divided into first and second streams, the first stream is supplied to the third passage means and the second stream is supplied to inlets to the second group of the first passage means as fuel. Solid oxide fuel cells or molten carbonate fuel cells are used.

Abstract: The method involves using an acoustic wave generating apparatus, such as an "air gun", which employs only a single gas or single gas mixture and which has a gas pressurizable chamber with an inlet for permitting pressurized gas to be introduced into the chamber and a closed outlet which can be opened rapidly to release pressurized gas from the chamber into a liquid to generate acoustic wave energy. Hydrogen and/or helium is/are used instead of air as the gas with the result that the strength and quality of the initial pulse of the generated wave energy is improved.

Abstract: A method for lining a pipe or main comprising heating a length of synthetic-resin liner pipe 20 of external diameter substantially equal to or greater than the internal diameter of the pipe or main 40 to be lined, mechanically deforming the heated liner pipe 20 to reduce its external diameter to less than the internal diameter of the pipe or main 40 to be lined, causing the liner pipe 20 to enter the pipe or main 40 to be lined and pressurizing the internal wall of the liner pipe 20 to cause it to expand into engagement with the internal wall of the pipe or main 40 to be lined.