Abstract: An electronic apartment station intercom unit, housed in a vandal proof enclosure, providing a means for a tenant to communicate with apartment building main entrance door panel and means to unlock said door. This unit has a power storage unit that enables this unit to be compatible with existing apartment building switching units. This power storage unit can be in the form of capacitors. In addition, this unit also contains a timer to shut the intercom unit off after a preset period of time.

Abstract: An electronic apartment station intercom unit, housed in a vandal proof enclosure, providing a means for a tenant to communicate with apartment building main entrance door panel and means to unlock said door. This unit has a power storage unit that enables this unit to be compatible with existing apartment building switching units. This power storage unit can be in the form of capacitors. In addition, this unit also contains a timer to shut the intercom unit off after a preset period of time.

Abstract: A key actuated lock is mounted within a protective enclosure which has a double hinged panel cover that projects into a slot between the bottom panel of the protective enclosure and the bottom of the lock mounted within the protective enclosure when the double hinged panel cover is closed. Both the protective enclosure and the double hinged panel cover have apertures that align when the double hinged panel cover is closed. Actuation of the lock within the protective enclosure moves a locking bolt from a unlocked retracted position to a locked extended position that projects the locking bolt through the two aligned apertures, thereby holding the double hinged panel cover closed.

Abstract: Method for removal of plutonium impurity from americium oxides and fluorides. AmF.sub.4 is not further oxidized to AmF.sub.6 by the application of O.sub.2 F at room temperature, while plutonium compounds present in the americium sample are fluorinated to volatile PuF.sub.6, which can readily be separated therefrom, leaving the purified americium oxides and/or fluorides as the solid tetrafluoride.

Abstract: A valve which may be interposed in a pipeline system in such a manner for injecting or launching of spheres into the interior of the pipeline individually and in sequence, and which may be alternatively interposed in the system for receiving previously injected spheres from the interior of the pipeline. The valve comprises a launch mechanism actuated by gravity and which has a single moving part, and in the receiving operation a blocking bar is provided for precluding incoming spheres from inadvertently or accidentally lodging within the valve body.