Abstract: The wireless earphone (1) comprises a housing (2) having a bud portion abutting an elongated stem portion. The bud portion is to fit within an ear. The bud portion has a primary sound outlet (5) at its far end that is to be inserted into an outer ear canal, and abuts the stem portion at its near end. A speaker driver (6) is inside the bud portion. Electronic circuitry (7,24) inside the housing (2) includes a wireless communications interface (4) to receive audio content over-the-air and in response provides an audio signal to the speaker driver. A rechargeable battery (3) as a power source for the electronic circuitry is located inside a cavity of the stem portion.

Abstract: An energy storage and conversion system utilizes unique heat exchange media for storing and transferring heat. In one embodiment, a refractory material is heated to the molten state by a solar furnace. The refractory material is stored in its molten form and metered to a direct-contact heat exchanger. It is fed into the heat exchanger in a plurality of streams that break into a plurality of droplets. The droplets flow through the heat exchanger in countercurrent relationship with a relatively inert gas such as argon or nitrogen. The gas is heated and expanded through an expansion engine to convert the thermal energy to mechanical energy which in turn can be utilized to produce electricity, for example. The refractory can be sufficiently cooled in the heat exchanger to fuse into beads, which can be easily recycled to the solar furnace.