Safety fuse properties

Thermal conductivity detector. The most important of the bulk physical property detectors is the thermal conductivity detector (TCD) which is a universal, non-destructive, concentration-sensitive detector. The TCD was one of the earliest routine detectors and thermal conductivity cells or katharometers are still widely used in gas chromatography. These detectors employ a heated metal filament or a thermistor (a semiconductor of fused metal oxides) to sense changes in the thermal conductivity of the carrier gas stream. Helium and hydrogen are the best carrier gases to use in conjunction with this type of detector since their thermal conductivities are much higher than any other gases on safety grounds helium is preferred because of its inertness. 

Since desorption depends only on the outer barrier layers, multiple lamination offers no advantage in controlled release other than perhaps a safety factor. That is, damage to a single laminate might produce catastrophic dumping, while damage to the outer layer of a multilaminate would only result in a minor disruption of the release. Provided vesicles do not fuse or burst, liposomes and unilamellar vesicles should have identical release properties. 

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