A semiconductor liquid junction photocell in which the photocell is in the configuration of a light concentrator and in which the electrolytic solution both conducts current and facilitates the concentration of incident solar radiation onto the semiconductor. The photocell may be in the configuration of a non-imaging concentrator such as a compound parabolic concentrator, or an imaging concentrator such as a lens.

This invention teaches a control to be used in smelting aluminum by the electrolysis breakdown of alumina (Al/sub 2/O/sub 3/) in a molten electrolyte heated to approximately 950 to 1000/sup 0/C. The invention provides a sonic resonator and control that can accurately detect the resonant frequency of the resonator in the molten electrolyte. The resonator preferably is made with tubular side wall 1/4 of the sonic wavelength, or is a quarter wave resonator. A wave generator inputs a signal having a range of frequencies that includes the resonant frequency, so that a peak resonant output at the resonant frequency can be detected on an oscilloscope or like detector. This instantaneous resonant frequency is then checked against an accurate data base correlating the resonant frequencies of the resonator in the electrolyte at specific alumina concentrations normally experienced throughout the electrolysis cycle. The electrolysis cycle can thus be controlled and recharged at any predetermined low alumina concentration greater than where the anode effect phase of the cycle normally might begin.

A system for analyzing constituents of coal-derived materials comprises three adsorption columns and a flow-control arrangement which permits separation of both aromatic and polar hydrocarbons by use of two eluent streams. 4 figures.

Handwritten notes and transcriptions of Akha songs and ritual recitations with partial English glossing.

Speech; Soviet naval threat; Soviet military capability; Comparison of U.S. fleet and Soviet fleet; Separation of Navy and Merchant Marine in the USA; Importance of U.S. Merchant Marine.

Transcript for Pedro J. Gonzalez interview (tape I side 2). A wide column of paragraphed text is printed across the fronts of two pages. Handwritten words sit between the printed text and each page's left edge.