Author

Schilling

Date of Award

8-1983

Degree Name

Master of Arts

Department

Chemistry

First Advisor

Dr. James Howell

Second Advisor

Dr. Robert Anderson

Third Advisor

Dr. Ralph Steinhaus

Access Setting

Masters Thesis-Open Access

Abstract

A Jarrell-Ash Atomic Absorption/Flame Emission 82-360 Spectrometer was interfaced to a Heathkit ETA-3400 microprocessor. The microprocessor is used to pulse the hollow cathode lamp from a "steady" current to a "peak " current during the opening of the chopper. The current from the photomultiplier-tube is converted to a proportional voltage which is supplied to a sample-and-hold circuit. A successive approximation routine is used to convert the voltage to a representative digital value. Digital values are obtained for the "blank" and "sample" and are used to calculate percent absorption values. The system can also be used to obtain emission values.

The system was used to determine the concentration of chromium and nickel in steel by the "standard addition method". As light loss in sensitivity was found at higher lamp intensities.

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