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Page 6186, results 154626 - 154650

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Some observations on rutherfordine
Joan R. Clark, C. L. Christ
1956, Trace Elements Investigations 584
The optical properties of rutherfordine, UO2CO3, previously determined on microscopic crystals, have been redetermined on considerably larger crystals; and the relations among the indices of refraction, the morphology, and the crystal structure have been examined. Rutherfordine is orthorhombic, biaxial positive, with α = 1.715, β = 1.730, γ =...
Behavior of Colorado Plateau uranium minerals during oxidation
Robert Minard Garrels, C. L. Christ
1956, Trace Elements Investigations 588
Uranium occurs as U(VI) and U(IV) in minerals of the Colorado Plateau ores. The number of species containing U(VI) is large, but only two U(IV) minerals are known from the Plateau: uraninite, and oxide, and coffinite, a hydroxy-silicate. These oxidize to yield U(VI) before reacting significantly with other...
Rapid-scanning microphotometry
A.W. Helz
1956, Trace Elements Investigations 579
A rapid-scanning microphotometer is described with which a 10-inch spectrum may be scanned in two minutes. The resulting chart may be 60, 300, or 1,500 cm long (wavelength scale) and 4 cm high (intensity scale). Commercially available components are used....
Summary of the mineralogy of the Colorado Plateau uranium ores
Alice D. Weeks, Robert Griffin Coleman, Mary E. Thompson
1956, Trace Elements Investigations 583
In the Colorado Plateau uranium has been produced chiefly from very shallow mines in carnotite ores (oxidized vanadiferous uranium ores) until recent deeper mining penetrated black unoxidized ores in water-saturated rocks and extensive exploration has discovered many deposits of low to nonvanadiferous ores. The uranium ores include a wide...
The determination of calcium in phosphate, carbonate, and silicate rocks by flame photometer
Henry Kramer
1956, Trace Elements Investigations 623
A method has been developed for the determination of calcium in phosphate, carbonate, and silicate rocks using the Beckman flame photometer, with photomultiplier attachement. The sample is dissolved in hydrofluoric, nitric, and perchloric acids, the hydrofluoric and nitric acids are expelled, a radiation buffer consisting of aluminum, magnesium, iron, sodium, potassium,...
The determination of uranium (IV) in apatite
Roy S. Clarke Jr., Zalman S. Altschuler
1956, Trace Elements Investigations 637
Geologic and mineralogic evidence indicate that the uranium present in apatite may proxy for calcium in the mineral structure as U(IV). An experimental investigation was conducted and chemical evidence was obtained that establishes the presence of U(IV) in apatite. The following analytical procedure was developed for the determination of U(IV). Carbonate-fluorapatite...
Comparison of the pebbles of the Shinarump and Moss Back members of the Chinle formation
Howard Franklin Albee
1956, Trace Elements Memorandum 832
Lithology, color, size, sphericity, and roundness of pebbles from the Shinarurnp and Moss Back members of the Chinle formation were analyzed and compared. The difference in the quartz:quartzite:chert ratios of the pebbles, the presence of limestone and siltstone pebbles, and to a lesser degree,the difference in color of pebbles serve...
Semiquantitative spectrographic analysis and rank correlation in geochemistry
Francis J. Flanagan
1956, Trace Elements Investigations 628
The rank correlation coefficient, rs, which involves less computation than the product moment correlation coefficient, r, can be used to indicate the degree of relationship between two elements. The methods is applicable in situations where the assumptions underlying distribution correlation theory may not be satisfied. Semiquantitative spectrographic analyses can be...
Occurrence of selenium in sulfides from some sedimentary rocks of the western United States
Robert G. Coleman, Maryse Delevaux
1956, Trace Elements Investigations 632
Investigations of the minor- and trace-element content of sulfides associated with uranium ore deposits from sandstone-type deposits have shown that selenium commonly substitutes for sulfur. The Morrison formation and Entrada sandstone of Jurassic age and the Wind River formation of Eocene age seem to be seleniferous stratigraphic zones; sulfides deposited...
The absorption spectra of the complexes of uranium (VI) with some β-diketones
H.I. Feinstein
1956, Trace Elements Investigations 631
The absorption spectra of the complexes of uranium (VI) with four β-dike tones were determined under various conditions of pH, concentration of uranium, and alcohol concentration. Under optimum conditions, the maximum molar absorptivity (31,200) is obtained using 2-furoyltrifluoroacetone. This compares with about 4,000 and 19,000 for the thiocyanate and dibenzoylmethane...