Abstract: A method of assaying the antioxidant activity of a range of plant, animal or synthetic oils and other similar substances in a liquid phase. The method consists in forming an oil-in-water emulsion with a surfactant, adding an ethene generator substrate and an oxidative peroxyl radical solution and measuring the ethene produced by a flow tube technique or atmospheric chemical ionisation methodology.

Abstract: A method of improving the signal intensity of precursor ions in the flow tube of a SIFT-MS instrument by separately and simultaneously injecting a first buffer gas and a second buffer gas into the flow tube through separate concentric apertures in a flange located in a venturi type inlet, the venturi including a central orifice through which precursor ions art also injected into the flow tube.

Abstract: A method of detecting a substance present in a gas or a gas mixture using SIFT-MS technology comprising the steps of inducing a supply of alkoxmethyl cations into the inlet of the flow tube, reacting a sample of the as with the alkoxymethyl cations, analysing the reacted gas sample, and calculating the concentration of trace levels of molecules containing heteroratoms in the reacted gas sample.

Abstract: A direct comparisons of the antioxidant activities of various pure compounds (eg., Trolox®(6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), extracts and biological fluids (eg. human plasma) can be effected by means of standardisable, objective method of determining and measuring the antioxidative and oxidative radical scavenging activities of a natural or synthetic substance, including the measurement of an indicator reaction product gas, ethylene, in the reaction headspace using Selective Ion Flow Tube Mass Spectrometry (SIFT-MS). This method assays ethylene liberated from ?-keto-?-methiolbutyric acid (KMBA) on reaction with peroxy radicals, other radicals or other reactive oxygen species that can oxidise KMBA to ethylene. From the production rate and concentration of the ethylene, the total antioxidant activity of an added analyte in question and its rate of reaction with oxidative free radicals may be determined.

Abstract: Rigid foam material, for example, expanded polystyrene foam, is drilled using a bit that forms an annular slit in the foam material and compresses the block temporarily around the slit. This frees the core for ready removal. The drill bit has a cutting ting at the leading end with an inside cutting edge and an annular bevel leading from the cutting edge to the outside surface of the cutting ring. The cutting ring is mounted on the leading end of a tube with an inside diameter greater than the inside diameter of the cutting ring in order to clear the core and an outside diameter less than the outside diameter of the cutting ring in order to clear the surrounding foam material.