Abstract: An automated gas cylinder monitoring system includes: a data storage collar associated with a gas cylinder including a resident memory and an insulated housing, the insulated housing being configured for coupling with a gas cylinder; a read/write probe for writing data to and receiving data from the resident memory of said data storage collar; measuring devices for determining the volume of gas in a gas cylinder; and a host computer for transmitting information to and receiving information from the read/write probe.

Abstract: Improved techniques are provided for forming a very thin polycrystalline layer of a semiconductor material on a glass substrate. The film material may be formed from a slurry of a semiconductor powder and a liquid carrier, and the slurry economically applied at room temperature by spraying techniques. Once dried, the film is compressed by the application of a substantial mechanical force. The compressed film is regrown in a heated atmosphere, forming a polycrystalline film comprised of large mean diameter crystals, with many crystals having a mean diameter in excess of the film thickness. A high quality cadmium sulfide polycrystalline film suitable for forming a photovoltaic cells may be inexpensively manufactured according to these techniques.