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M. W. Skougstad

Publications and source records attributed to M. W. Skougstad.

7 recordsLinked to original sources
USGS2002

Indirect spectrophotometric determination of traces of bromide in water

A rapid, accurate, and sensitive indirect spectrophotometric method for the determination of bromide in natural waters is based on the catalytic effect of bromide on the oxidation of iodine to iodate by potassium permanganate in sulfuric acid solution. The method is applicable to concentrations ranging from 1 to 100 μ g. of bromide per liter, but may be modified to extend the concentration range. Most ions commonly occurring in water do not interfere. The standard deviation is 2.9 at bromide concentrations of 100 μ g. per liter and less at lower concentrations. The determination of bromide in samples containing known added amounts gave values ranging from 99 to 105% of the concentration calculated to be present.

Analytical Chemistry↗
USGS1964

Catalytic determination of vanadium in water

A kinetic determination of V(V) as a catalyst was spectrophotometrically performed by using the indicator reaction of Gallamine blue (GB + ) and bromate at pH 2.0. The reaction was followed by measuring absorbance change for a fixed-time of 3 min at 537 nm. The variables such as reagent concentration, pH, buffer concentration, ionic strength and temperature were optimized to improve the selectivity and sensitivity. Under the optimized conditions, the determination of V(V) was performed in the range 1–100 μg L −1 with limits of detection and quantification of 0.31 and 0.94 μg L −1 . The developed kinetic method is sufficiently sensitive, selective and simple. It was successfully applied to the speciative determination of total V and inorganic dissolved vanadium species, V(V) and V(IV) in environmental water samples. The oxidizing property of permanganate is used to differentiate between V(IV) and V(V) species. The V(IV) content was found by subtracting the V(V) content from those of total V. The recovery is above 95% for V(V) spiked samples. Additionally, the accuracy was validated by analysis of a certified water sample, CRM TMDA-53.3, and the results were in good agreement with the certified value.

Analytical Chemistry↗
USGS1960

Occurrence of strontium in natural water

The regions where the stable strontium content of surface waters is relatively low (less than 0.50 ppm) include the Pacific Northwest, Northeastern United States, and the Central Lowlands, Particularly the Lower Mississippi basin and the Western Gulf Coast area. Moderate concentrations of strontium (0.50 to 1.5 ppm) are found in streams of Southeastern United States, most of the Great Plains Region, the Western Mountain and Plateau Regions, and California. Relatively high concentrations of strontium occur in the surface waters of an area that includes Northern and Western Texas and Southern New Mexico and Arizona. Exceptions to the above distribution are due to local geologic conditions.

Circular↗