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Geology topics

J.J. Warr

Publications and source records attributed to J.J. Warr.

3 recordsLinked to original sources

Retention of lead during oxidative ashing of selected naturally occurring carbonaceous substances

The amount of lead retained in the ash of lead-bearing carbonaceous material is essentially independent of the method of ashing. Samples containing lead in the range of 0.00X to 0.X per cent were ashed by ignition in a high-oxygen atmosphere and were also wet-ashed. The lead in the ash was determined colorimetrically. Results were the same by both methods, but the time required is 3 to 10 times less for the dry-ashing method.

Geochimica et Cosmochimica Acta↗

Modification to Tracerlab Automatic Sample Changer

The U.S. Geological Survey has recently modified the Tracerlab Automatic Sample Changer so that the geometry is greatly improved for counting larger low-activity samples in finely ground form. The larger sample and larger Geiger Mueller tubes allow a greater number of samples to be counted per hour with the same statistical accuracy.

Trace Elements Memorandum↗