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Geology topics

D. E. Erdmann

Publications and source records attributed to D. E. Erdmann.

7 recordsLinked to original sources
USGS1985

QUALITY ASSURANCE OF U. S. GEOLOGICAL SURVEY WATER-QUALITY FIELD MEASUREMENTS.

Reference samples are submitted semiannually to field analysts for measurement of these parameters with the same techniques and instruments used in the field. Both the personnel and the instruments involved in making the determinations are recorded. When the data are complete, a report defining the quality of the analytical results is prepared and circulated to appropriate District, Regional, and National offices. Field data, in addition to their immediate use, are normally placed in a national data base and are available to all hydrologists. As a result, the quality of field measurements can have a profound effect on their investigations. The quality assurance program described is designed to insure that the field data of the Water Resources Division are highly accurate.

Conference Paper↗
USGS1983

Automated determination of bromide in waters by ion chromatography with an amperometric detector

An automated ion chromatograph, including a program controller, an automatic sampler, an integrator, and an amperometric detector, was used to develop a procedure for the determination of bromide in rain water and many ground waters. Approximately 10 min is required to obtain a chromatogram. The detection limit for bromide is 0.01 mg l −1 and the relative standard deivation is <5% for bromide concentrations between 0.05 and 0.5 mg l −1 . Chloride interferes if the chloride-to-bromide ratio is greater than 1 000:1 for a range of 0.01–0.1 mg l −1 bromide; similarly, chloride interferes in the 0.1–1.0 mg l −1 range if the ratio is greater than 5 000:1. In the latter case, a maximum of 2 000 mg l −1 of chloride can be tolerated. Recoveries of known concentrations of bromide added to several samples, ranged from 97 to 110%.

Analytica Chimica Acta↗