TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The propellant comprises a pressurized gas, and at least one of carbon dioxide, argon, nitrogen or helium, where the pressurized gas is supplied by a carbon dioxide cartridge.    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The first seal comprises an O-ring between the spray housing and the propellant housing. The second seal comprises an O-ring between the spray housing and the propellant housing. The spray housing comprises a spike to release the propellant from the propellant chamber and into the passage within the spray housing supplying the propellant into the liquid chamber, when the propellant housing is engaged with the spray housing. The spike punctures the propellant chamber when the propellant housing is engaged with the spray housing. The spike actuates a valve within the propellant housing releasing the propellant from the propellant chamber when the propellant housing is engaged with the spray housing. The adaptor housing comprises a spike to release the propellant from the propellant chamber of the base hosing and into the passage within the adaptor housing supplying the propellant into the liquid chamber, when the propellant housing is engaged with the adaptor housing. The spike punctures the propellant chamber when the propellant housing is engaged with the adaptor housing. The spike actuates a valve within the propellant housing releasing the propellant from the propellant chamber when the propellant housing is engaged with the adaptor housing. The first seal comprises an O-ring between the spray housing and adaptor housing. The second seal comprises an O-ring between the adaptor housing and the propellant housing. The propellant cartridge is a carbon dioxide cartridge, and has a male thread which engages a female thread within the adaptor housing.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The propellant comprises an aerosol having a boiling point lower than 60 degrees F at atmospheric pressure. The aerosol comprises at least one of chlorofluorocarbon, propane, n-butane, isobutene, dimethyl ether, methyl ethyl ether, nitrous oxide, carbon dioxide or hydrofluoroalkanes.