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Kam Wo Leong

Publications and source records attributed to Kam Wo Leong.

2 recordsLinked to original sources

Distribution of copper, lead, zinc, mercury, and arsenic in the surface sediments off the coast of northwestern Alaska

Increasing interest in potentially harmful substances utilized and discarded by man has raised question about the normal distribution of chemical elements in the natural environment. This interest prompted a baseline study of a pristine region off the northern coast of Alaska. Information was gathered on currents, water clarity, nutrients, temperature and salinity, zooplakton, benthic communities, neritic fauna, bird and mammal population and pesticide residues, sediment composition and chemistry of the sediments and their interstitial waters. This information will provide a base for ascertaining and evaluating future changes and for assessment of the potential hazard in this region and ecosystems elsewhere.

Alaska

Field determination of nanogram quantities of mercury in soils and rocks

A method for determining nanogram quantities of mercury in geological materials is based on the catalytic effect of mercury on the reaction of ferrocyanide with nitrosobenzene to produce a violet-covered compound whose intensity if proportional to the mercury present. The mercury is released by heating a sample of soil or crushed rock to about 650°C. As little as 30 nanograms of mercury (30 parts per billion with 1 gram sample) can be detected. The reliability of the method is adequate to permit its use in geochemical surveys that utilize mercury as a pathfinder element.

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