Spectrochemical computer analysis - instrumentation

A.W. Helz

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USGS · 70160814

Spectrochemical computer analysis - instrumentation

A.W. Helz

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Abstract

A microphotometer is described for making magnetic tape recordings of spectra 480 mm long from 102- by 508-mm photographic plates. Transmission readings are recorded at a rate exceeding 1,300 per second for every 5.08 um of length of the spectrum, A two-line cadmium fiducial line system and a developing tank for 102- by 508-mm plates also are described as equipment ancillary to a system of computer spectral analysis applied to the spectrochemical analysis of geologic materials.

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A.W. Helz. 1973. Spectrochemical computer analysis - instrumentation. https://pubs.usgs.gov/publication/70160814

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