Abstract: A process for the production of durable photocatalytically active self-cleaning coating on glass by contacting a hot glass surface with a fluid mixture of titanium chloride, a source of oxygen and a tin precursor. The coating preferably comprises less than 10 atom % tin in the bulk of the coating and preferably there is a greater atomic percent tin in the surface of the coating than there is in the bulk of the coating. Preferably, the coating is durable to abrasion and humidity cycling.

Abstract: A coated substrate, especially a glass substrate, such coated substrate having high photocatalytic activity and low visible light reflection as well as being highly abrasion resistant. Preferably, the coating is a titanium oxide coating, the photolytic activity is greater than 5×10−3 cm−1min−1, and coating side visible light reflection is 35% or lower.

Abstract: A method and apparatus for providing a self-sustaining precise voltage and current feedback biasing loop. The present invention provides a circuit for initially biasing the bandgap and master bias current generator at startup. The feedback biasing loop has loop dynamics that are chosen such that the gain of the positive feedback loop is less than one so that the loop will not oscillate under normal operation after power-up.

Abstract: A method and apparatus for matching common mode output voltage at a switched-capacitor to continuous-time interface. An active continuous time summation circuit is used at the output of the switched-capacitor stage to derive the common mode level that is at the output of the switched-capacitor stage. This derived signal is filtered to remove any noise component remaining in it, and is then used as the reference common mode signal in the continuous time stage. This forces the output common mode, and hence the input common mode of the unity gain amplifier stage, to track the common mode output of the switched-capacitor stage. This adaptive tracking eliminates the common mode interface error, which could be present and could vary from die to die (due to parasitic variations). This technique ensures proper tracking of the DC levels between the negative and the positive terminals of the unity gain amplifier, which is essential for low distortion operation of the amplifier.

Abstract: A transfer line used between a gas chromatograph and an ion source of a mass spectrometer is constructed with an inner tube, a middle tube and an outer tube. Disposed within the middle tube are a heater unit which extends along the middle tube and a sensor well. The remaining air space in the middle tube is filled with compacted fine thermally conductive powder. Thermal insulation is provided between the middle and outer tubes. End seals are provided to maintain the integrity of the vacuum system of the mass spectrometer.

Abstract: A method for determining the position of a leak in a conduit or pipeline, especially one of small diameter, in which a carrier body, for example a short length of co-axial cable, carrying a short-lived radioisotope is inserted into the conduit or pipeline and is caused to move along it by pressuring up the conduit or pipeline from one or both ends thereof with fluid, for example water. The carrier body travels to the leak but no further and its location is detected from outside the conduit or pipeline using a radiation detector.

Abstract: A valve assembly for allowing entry of a sampling device or probe device from an ambient atmosphere to a vacuum chamber comprises an electromagnet means which controls a ball made of magnetic material. Upon entry of the device into an entry inlet of the apparatus, the ball is seated in response to activation of the electromagnet means so as to seal an aperture leading to the vacuum chamber. As the device is moved towards the vacuum chamber, the magnetic force is removed, which allows the ball to drop away from the aperture allowing entry of the device into the vacuum chamber. Upon withdrawal of the device from the vacuum chamber, the ball is actuated by the electromagnet to seal the aperture, thereby maintaining the integrity of the vacuum system.

Abstract: Method and apparatus to determine the position of a liquid/liquid or liquid/vapor interface in a remote inaccessible location, for example in undersea oil storage tanks, by exposing the liquids or liquid and vapor to gamma-radiation from a source adjacent to or within the vessel containing the liquid(s) and monitoring the gamma-radiation issuing from the liquids or liquid and vapor, and using long lengths of optical fibre to convey the signals received to a measuring instrument. The invention employs optical fibres which may be up to several hundred meters long and among its advantages is the need for no moving parts, electrical supply or electronics at the remote location.

Abstract: A method and apparatus for determining the position of a valve for example ball valves, plug valves, gate valves using a source of radiation such as cesium-137 located either on or adjacent to the external surface of the valve or within the valve itself, for example in the ball of a ball valve, and a radiation detector such as a Geiger-Muller tube on the external surface of the valve. Source and detector are aligned and located relative to one another so that the count rate detected is indicative of the valve position. The method is accurate and, for example, allows the position of the ball in a ball valve to be monitored to within .+-.1 mm.