Abstract: A sensor for passively measuring a maximum temperature within a nuclear reactor comprises a substrate, and a plurality of melt wires within a cavity defined within the substrate, at least one melt wire of the plurality of melt wires exhibiting a variable melting temperature along a length of the at least one melt wire. Related sensors and methods of forming the sensors are also disclosed.

Abstract: A sensor for passively measuring a maximum temperature within a nuclear reactor comprises a substrate, and a plurality of melt wires within a cavity defined within the substrate, at least one melt wire of the plurality of melt wires exhibiting a variable melting temperature along a length of the at least one melt wire. Related sensors and methods of forming the sensors are also disclosed.

Abstract: Sealed camera apparatus may include a generally closed chamber having at least one transparent window provided therein. A video camera mounted within the generally closed chamber receives light transmitted through the at least one transparent window. A radio transmitter mounted within the generally closed chamber is operatively associated with the video camera. A heat conduit having a first end and a second end extends through an opening provided in the generally closed chamber so that the first end of the heat conduit is located interior to the generally closed chamber and so that the second end of the heat conduit is located exterior to the generally closed chamber. The first end of said heat conduit is in thermal contact with at least a portion of the radio transmitter so that heat from the radio transmitter is transferred to the heat conduit. A heat sink mounted to the second end of the heat conduit dissipates heat from the transmitter and conducted through the heat conduit.