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W.L. Lamar

Publications and source records attributed to W.L. Lamar.

9 recordsLinked to original sources
USGS2002

Determination of small quantities of fluoride in water: A modified zirconium-alizarin method

The zirconium-alizarin method has been modified to facilitate the convenient and accurate determination of small amounts of fluoride in a large number of water samples. Sulfuric acid is used to acidify the samples to reduce the interference of sulfate. The pH is accurately controlled to give the most sensitive comparisons. Most natural waters can be analyzed by the modified procedure without resorting to correction curves. The fluoride content of waters containing less than 500 parts per million of sulfate, 500 parts per million of bicarbonate, and 1000 parts per million of chloride may be determined within a limit of about 0.1 part per million when a 100-ml. sample is used.

Industrial And Engineering Chemistry Analytical Ed↗
USGS2002

Determination of fluoride in water. A modified zirconium-alizarin method

A convenient, rapid colorimetric procedure using the zirconium-alizarin indicator acidified with sulfuric acid for the determination of fluoride in water is described. Since this acid indicator is stable indefinitely, it is more useful than other zirconium-alizarin reagents previously reported. The use of sulfuric acid alone in acidifying the zirconium-alizarin reagent makes possible the maximum suppression of the interference of sulfate. Control of the pH of the samples eliminates errors due to the alkalinity of the samples. The fluoride content of waters containing less than 500 parts per million of sulfate and less than 1000 p.p.m. of chloride may be determined within a limit of 0.1 p.p.m. when a 100-ml. sample is used.

Industrial and Engineering Chemistry↗
USGS1949

Determination of color of turbid waters

A convenient procedure for determining the color of turbid waters, using the principle of precipitation of turbidity by the electrolyte calcium chloride, is described. Because the stable turbidity of many surface waters cannot be completely precipitated by conventional centrifuging alone, this procedure presents a means of flocculating the turbidity without affecting the true color of the water. In the determination of true color of turbid samples one of the most prevalent errors is caused by the reading of color on samples not completely free of turbidity. Pertinent data are presented on color and turbidity of waters as related to the principles involved in the determination of color.

Analytical Chemistry↗