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Page 6971, results 174251 - 174275

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Publication Extents

Not all publications have extents, not all extents are completely accurate
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...
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...
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...
Rapid determination of carbon dioxide in silicate rocks
L. Shapiro, W. W. Brannock
1955, Analytical Chemistry (27) 1796-1797
In the development of rapid methods for silicate rock analysis, a simpler and faster means was needed for the determination of carbon dioxide than the conventional "train" procedures. With the method presented here, which involves measurement of the volume of carbon dioxide evolved, the time required for a determination is...
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 thorium and of rare earth elements in cerium earth minerals and ores
M. K. Carron, D. L. Skinner, R.E. Stevens
1955, Analytical Chemistry (27) 1058-1061
The conventional oxalate method for precipitating thorium and the rare earth elements in acid solution exhibits definite solubilities of these elements. The present work was undertaken to establish conditions overcoming these solubilities and to find optimum conditions for precipitating thorium and the rare earth elements as hydroxides and sebacates. The...
Rapid determination of water in silicate rocks
Leonard Shapiro, W. W. Brannock
1955, Analytical Chemistry (27) 560-562
A rapid and simple method for the determination of total water in silicate rocks has been developed by modifying the Penfield procedure. In this method, the time required for a single determination has been reduced to less than 10 minutes. Comparison of the data obtained by this modification and the...
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...
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....
Artificial propagation of the sea lamprey Petromyzon marinus
Robert E. Lennon
1955, Copeia (1955) 235-236
Observations on the gland products, gonads, and general characteristics of sexually mature sea lampreys, Petromyzon marinus (Linnaeus), from Lake Huron, and a need to obtain some information on very young larval lampreys, prompted an experiment on the stripping and hatching of eggs. Seventeen specimens were selected from a group of...
Sediment investigations of the Platte River near Overton, Nebraska
C.D. Albert, H.P. Guy
1955, Report
This report contains results of sediment-transport investigations on the Platte River near Overton,. Nebr. from January 1950 to September 1953. The basic data of suspended-sediment studies, results of bed-material analyses, and determinations of water-surface slopes from staff readings are given. The data indicate that a reliable determination of suspended sediment, hence...
Ground water resources of southeastern Oakland County, Michigan
J.G. Ferris, E.M. Burt, G.J. Stramel, E. G. Crosthwaite
1954, Report
The area covered by this report comprises a square which measures three townships on a side and enclose 318 square miles in southeastern Oakland County. The investigation of the ground-water resources of this area was made by the U.S. Geological Survey in cooperation with the Detroit Metropolitan Area Regional Planning...
Geology and ground-water resources of Wichita and Greeley Counties, Kansas
G.C. Prescott Jr., J.R. Branch, W.W. Wilson
1954, Kansas Geological Survey Bulletin (108)
This report describes the geography, geology, and ground-water resources of Wichita and Greeley counties in western Kansas. The area consists of a flat to gently rolling plain, which slopes eastward [at] about 15 feet per mile. A short reach of Ladder Creek (Beaver) is the only perennially flowing stream in...