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Results for “double-junction”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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Residual water bactericide monitor development program

A silver-ion bactericidal monitor is considered for the Space Shuttle Potable Water System. Potentiometric measurement using an ion-selective electrode is concluded to be the most feasible of available techniques. Four commercially available electrodes and a specially designed, solid-state, silver-sulfide electrode were evaluated for their response characteristics and suitability for space use. The configuration of the solid-state electrode with its Nernstian response of 10 to 10,000 ppb silver shows promise for use in space. A pressurized double-junction reference electrode with a quartz-fiber junction and a replaceable bellows electrolyte reservoir was designed verification-tested, and paired with a solid-state silver-sulfide electrode in a test fixture.

Source record↗

Preliminary flight prototype silver ion monitoring system

The design, fabrication, and testing of a preliminary flight prototype silver ion monitoring system based on potentiometric principles and utilizing a solid-state silver sulfide electrode paired with a pressurized double-junction reference electrode housing a replaceable electrolyte reservoir is described. The design provides automatic electronic calibration utilizing saturated silver bromide solution as a silver ion standard. The problem of loss of silver ion from recirculating fluid, its cause, and corrective procedures are reported. The instability of the silver sulfide electrode is discussed as well as difficulties met in implementing the autocalibration procedure.

Brady, J.↗

Molecular-Beam-Epitaxy Program

Molecular Beam Epitaxy (MBE) computer program developed to aid in design of single- and double-junction cascade cells made of silicon. Cascade cell has efficiency 1 or 2 percent higher than single cell, with twice the open-circuit voltage. Input parameters include doping density, diffusion lengths, thicknesses of regions, solar spectrum, absorption coefficients of silicon (data included for 101 wavelengths), and surface recombination velocities. Results include maximum power, short-circuit current, and open-circuit voltage. Program written in FORTRAN IV.

Sparks, Patricia D.↗