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Geology topics

J.S. Wahlberg

Publications and source records attributed to J.S. Wahlberg.

7 recordsLinked to original sources
USGS2002

Volumetric determination of uranium: Titanous sulfate as reductant before oxidimetric titration

Need for a more rapid volumetric method for the routine determination of uranium in uranium-rich materials has led to the development of a method that uses titanous sulfate as a reductant before oxidimetric titration. Separation of the hydrogen sulfide group is not necessary. Interfering elements precipitated by cupferron are removed by automatic filtrations made simultaneously rather than by the longer chloroform extraction method. Uranium is reduced from VI to IV by addition of an excess of titanous sulfate solution, cupric ion serving as an indicator by forming red metallic copper when reduction is complete. The copper is reoxidized by addition of mercuric perchlorate. The reduced uranium is then determined by addition of excess ferric sulfate and titration with ceric sulfate. The method has proved to be rapid, accurate, and economical.

Analytical Chemistry↗
USGS1978

Preliminary analytical results for a new U.S. Geological Survey Devonian Ohio Shale Standard SDO-1

Using several analytical techniques, results of analysis of U. S. Geological Survey new standard SDO-1 are given for selected elements. The Devonian black shale shows an organic carbon content of approximately 10.3 percent, a sulfur content of approximately 5.6 percent, and a uranium content of approximately 56 ppm. Some elements show higher than average values for black shales: Mn, 389 ppm; Co, 57 ppm; Ni, 128 ppm; As, 104 ppm; and Hg, 0.19 ppm.

Open-File Report↗
USGS1969

Determination of rhenium in molybdenite by X-ray fluorescence. A combined chemical-spectrometric technique

Rhenium in molybdenite is separated from molybdenum by distillation of rhenium heptoxide from a perchloric-sulphuric acid mixture. It is concentrated by precipitation of the sulphide and then determined by X-ray fluorescence. From 3 to 1000 μg of rhenium can be measured with a precision generally within 2%. The procedure tolerates larger amounts of molybdenum than the usual colorimetric methods.

Talanta↗
USGS1964

Adsorption equilibria between earth materials and radionuclides, Cape Thompson, Alaska

The concept and the derivation of a distribution coefficient are developed. Ion exchange and the nature of competition among cations are given. Distribution coefficients for carrier-free cesium, strontium, and iodine were determined on 17 samples collected during July, 1961, in the vicinity of Cape Thompson, northwestern Alaska. High percentage uptake of these ions was measured under the test conditions. Cesium adsorption, at 1 day, was found to be represented by the mass-action equation. The distribution coefficients for cesium adsorption were so large that, in all but a few cases, very little of this nuclide would remain long in solution in the natural waters of the area. Strontium adsorption was found to be a function of the calcium-plus-magnesium concentration and to be independent of the sodium concentration. In most samples, its equilibrium is reached in less than 1 day. Iodine sorption varied with percent organic matter in the samples. If the iodine were in contact with organic matter for several days, a substantial part of it probably would be removed from solution in the natural waters.

Alaska↗