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Laura E. Reichen

Publications and source records attributed to Laura E. Reichen.

5 recordsLinked to original sources
USGS1951

Field method for the determination of molybdenum in plants

Fresh plant material is ashed directly by heating in nickel or platinum dishes over a "flame. An acid solution of 25 milligrams of ash is treated with stannous chloride and potassium thiocyanate. The amber-colored molybdenum thiocyanate complex ion is extracted with isopropyl ether, and the intensity of the color of the ether layer over a sample solution is compared with the ether layer over standard molybdenum solutions treated similarly. Field determinations can be made quickly and the method requires no special equipment. As little as 0.25 microgram or 0.001 percent molybdenum can be determined in plant ash.

Circular↗
USGS1947

The zinc content of plants on the Freidensville zinc slime ponds in relation to biogeochemical prospecting

The zinc content of thirty different kinds of plants growing on slime ponds containing on the average 12.5 per cent zinc were determined by the dithizone method. The zinc content ranged from 39 p.p.m. in the fruit of the false solomon's seal (Smilacina racemosa) to 5,400 in the horsetail (Equiseteum arvense}. This latter plant varied considerably in zinc at different places on the slime ponds. The zinc contents of the aspen (Populus grandidentata}, ragweed {Ambrosia artemisiifolia), and horsetail grown on normal soils are compared to those on the slime ponds and it is recommended that the poplar and ragweed be studied further as indicators of zinc ore bodies.

Pennsylvania↗