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Page 6211, results 155251 - 155275

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Flood control problems
Luna Bergere Leopold, Thomas Maddock Jr.
1955, Journal of Soil and Water Conservation in India (3) 169-173
Throughout the world, alluvial soils are among the most fertile and easiest cultivated. Alluvial valleys are routes for transportation either by water or by road and railroad. Rivers are sources of water, a necessity of life. But these river valleys and alluvial deposits, which have so many desirable characteristics and...
Determination of thorium by fluorescent x-ray spectrometry
I. Adler, J. M. Axelrod
1955, Analytical Chemistry (27) 1002-1003
A fluorescent x-ray spectrographic method for the determination of thoria in rock samples uses thallium as an internal standard. Measurements are made with a two-channel spectrometer equipped with quartz (d = 1.817 A.) analyzing crystals. Particle-size effects are minimized by grinding the sample components with a mixture of silicon carbide...
Determination of total sulfur content of sedimentary rocks by a combustion method
M. E. Coller, R. K. Leininger
1955, Analytical Chemistry (27) 949-951
Total sulfur has been determined in common sedimentary rocks by a combustion method. Sulfur contents range from 0.001 to 5.0%. Experiments show that the combustion method can be used in analyzing sedimentary rocks in which sulfur is present as sulfide, sulfate, or both. Pulverized samples from 0.100 to 0.500 gram...
Some contributions of the Cooperative Wildlife Research Units to forest wildlife management
Daniel L. Leedy
1955, Journal of Forestry (53) 630-635
Although the Cooperative Wildlife Research Unit Program is nationwide in scope and has been in existence since 1935, it is probable that many readers of the Journal of Forestry are unaquainted with the program's objectives and accomplishments. This paper was written at the suggestion of a S.A.F. member to provide...
Composition and origin of basaltic magma of the Hawaiian Islands
H. A. Powers
1955, Geochimica et Cosmochimica Acta (7) 77-107
Silica-saturated basaltic magma is the source of the voluminous lava flows, erupted frequently and rapidly in the primitive shield-building stage of activity, that form the bulk of each Hawaiian volcano. This magma may be available in batches that differ slightly in free silica content from batch to batch both at...
Field determination of microgram quantities of niobium in rocks
F. N. Ward, A. P. Marranzino
1955, Analytical Chemistry (27) 1325-1328
A rapid, simple, and moderately accurate method was needed for the determination of traces of niobium in rocks. The method developed is based on the reaction of niobium(V) with thiocyanate ion in a 4M hydrochloric acid and 0.5M tartaric acid medium, after which the complex is extracted with ethyl ether....
Determination of boron in silicates after ion exchange separation
Henry Kramer
1955, Analytical Chemistry (27) 144-145
Existing methods for the determination of boron in silicates are not entirely satisfactory. Separation as the methyl ester is lengthy and frequently erratic. An accurate and rapid method applicable to glass, mineral, ore, and water samples uses ion exchange to remove interfering cations, and boron is determined titrimetrically in the...
Determination of small and large amounts of fluorine in rocks
F. S. Grimaldi, B. Ingram, F. Cuttitta
1955, Analytical Chemistry (27) 918-921
Gelatinous silica and aluminum ions retard the distillation of fluorine in the Willard and Winter distillation method. A generally applicable, simple method for the determination of fluorine in rocks containing aluminum or silicon or both as major constituents was desired. In the procedure developed, the sample is fused with a...
The reproduction of lake trout in southern Lake Superior
Paul H. Eschmeyer
1955, Transactions of the American Fisheries Society (84) 47-74
The principal spawning grounds of lake trout (Salvelinus namaycush namaycush) in United States waters of southern Lake Superior are on rocky shoals at depths of less than 20 fathoms. Most spawning occurs in October and early November. Of the mature fish collected on or near the spawning grounds, 60...
Internal standards in fluorescent X-ray spectroscopy
I. Adler, J. M. Axelrod
1955, Spectrochimica Acta (7) 91-99
The use of internal standards in the analysis of ores and minerals of widely-varying matrix by means of fluorescent X-ray spectroscopy is frequently the most practical approach. Internal standards correct for absorption and enhancement effects except when an absorption edge falls between the comparison lines or a very strong emission...
Germanium and uranium in coalified wood from upper Devonian black shale
Irving A. Breger, J.M. Schopf
1955, Geochimica et Cosmochimica Acta (7) 287-293
Microscopic study of black, vitreous, carbonaceous material occurring in the Chattanooga shale in Tennessee and in the Cleveland member of the Ohio shale in Ohio has revealed coalified woody plant tissue. Some samples have shown sufficient detail to be identified with the genus Cauixylon....
Geology and ground-water resources of Webster County, Iowa
William E. Hale
1955, Water Supply Bulletin 4
Webster County, comprising an area of 718 square miles just northwest of the center of Iowa, had a population of 44,241 in 1950, with 25,115 in Fort Dodge, the principal city. Some 94.4 percent of the county is in farm land; corn is the principal crop and is used in...
Radioactive equilibrium in ancient marine sediments
Irving A. Breger
1955, Geochimica et Cosmochimica Acta (8) 63-73
Radioactive equilibrium in eight marine sedimentary formations has been studied by means of direct determinations of uranium, radium and thorium. Alpha-particle counting has also been carried out in order to cross-calibrate thick-source counting techniques. The maximum deviation from radioactive equilibrium that has been noted is 11 per cent—indicating that there...