Abstract: An exemplary candle comprises an outer tapered shell with a plurality of tapered sidewalls that are joined together at abutting edges. The shell comprises a material that does not completely melt when the candle is burned. A wick disposed within the shell, and paraffin is disposed the tapered shell to cover the wick except near the top of the candle where the wick is exposed, that is designed to melt when the candle is burned. The paraffin may comprise paraffin beads that partially fill the shell and cover the wick. An exemplary method includes providing a candle that has an outer shell made of a material that does not completely melt when the candle is burned, disposing a wick in the outer shell, and filling the outer shell with paraffin beads to surround the wick to a desired level that keeps an upper end of the wick exposed.

Abstract: A compact acoustic refrigeration system actively cools components, e.g., electrical circuits (22), in a borehole environment. An acoustic engine (12, 14) includes first thermodynamic elements (12) for generating a standing acoustic wave in a selected medium. An acoustic refrigerator (16, 26, 28) includes second thermodynamic elements (16) located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements (16) and a relatively hot temperature at a second end of the second thermodynamic elements (16). A resonator volume (18) cooperates with the first and second thermodynamic elements (12, 16) to support the standing wave.

Abstract: An apparatus for thermally protecting heat sensitive components of tools. The apparatus comprises a Dewar for holding the heat sensitive components. The Dewar has spaced-apart inside and outside walls, an open top end and a bottom end. An insulating plug is located in the top end. The inside wall has portions defining an inside wall aperture located at the bottom of the Dewar and the outside wall has portions defining an outside wall aperture located at the bottom of the Dewar. A bottom connector has inside and outside components. The inside component sealably engages the inside wall aperture and the outside component sealably engages the outside wall aperture. The inside component is operatively connected to the heat sensitive components and to the outside component. The connections can be made with optical fibers or with electrically conducting wires.

Abstract: An apparatus which thermally protects sensitive components in tools used in a geothermal borehole. The apparatus comprises a Dewar within a housing. The Dewar contains heat pipes such as brass heat pipes for thermally conducting heat from heat sensitive components to a heat sink such as ice.