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INVESTIGATION OF THE PHOTOCHEMICAL METHOD FOR URANIUM ISOTOPE SEPARATION

Description: To find a process for successful photochemical separation of isotopes several conditions have to be fulfilled. First, the different isotopes have to show some differences in the spectrum. Secondly, and equally important, this difference must be capable of being exploited in a photochemical process. Parts A and B outline the physical and chemical conditions, and the extent to which one might expect to find them fulfilled. Part C deals with the applicability of the process.
Date: July 10, 1943
Creator: Urey, H.C.

FISSION SPECTRUM

Description: Measurements of the spectrum of the fission neutrons of 25 are described, in which the energy of the neutrons is determined from the ionization produced by individual hydrogen recoils. The slow neutrons producing fission are obtained by slowing down the fast neutrons from the Be-D reaction of the Stanford cyclotron. In order to distinguish between fission neutrons and the remaining fast cyclotron neutrons both the cyclotron current and the pusle amplifier are modulated. A hollow neutron container, in which slow neutrons have a lifetime of about 2 milliseconds, avoids the use of large distances. This method results in much higher intensities than the usual modulation arrangement. The results show a continuous distribution of neutrons with a rather wide maximum at about 0.8 MV falling off to half of its maximum value at 2.0 MV. The total number of netrons is determined by comparison with the number of fission fragments. The result seems to indicate that only about 30% of the neutrons have energies below .8 MV. Various tests are described which were performed in order to rule out modification of the spectrum by inelastic scattering.
Date: August 18, 1943
Creator: Bloch, F. & Staub, H.

Production of (Uranium) Tetrafluoride

Description: Production of tetrafluoride for the month of April was 49,400. New equipment installed late in March operated smoothly and the production was slightly over the rated capacity of the plant. Nickel ends were welded on to the steel reactor tubes to prevent corrosion at the cover joint and possible contamination of the product with iron. The nickel ends will also save considerable repair work on the tube ends. The magnesium trays for some of the reactors are beginning to crack at the sides from frequent straightening. The trays are bent out of shape by the expansion of the product and are reshaped by hammering over a die. Some of the cracks have been repaired by welding but this is not very satisfactory because the welded trays are harder to straighten and often crack again.
Date: May 13, 1943
Creator: Long, K. E. & Swinehart, C. F.

Mollusca From the Miocene and Lower Pliocene of Virginia and North Carolina: Part 1. Pelecypoda

Description: Abstract: A brief sketch of the stratigraphy of the Miocene of Virginia and the Miocene and Pliocene of North Carolina was prepared by Dr. W. C. Mansfield before his death in July 1939. His purpose was "to provide a background of formational nomenclature" for the taxonomic treatment of the molluscan faunas. The physical nature and distribution of the upper Tertiary formations within those States are discussed, characteristic sections given, and diagnostic molluscan species listed. Part 1 of the systematic report covers the Pelecypoda. A monographic treatment is not attempted, but 132 previously known species are considered, and 62 new species and subspecies are described and figured.
Date: 1943
Creator: Gardner, Julia Anna

Report on Reserves and Production Situation of Vanadiferous and Related Ores in Colorado Plateau Region

Description: From introduction: The general distribution of known deposits of vanadium-bearing sandstone, which also contain some uranium and radium, is shown in figure 1 1/ and Exhibit A, plate 53. 2/ During 1939-41 the Geological Survey made detailed geological studies of these deposits in the Uravan district, Montrose County, Colorado, as well as preliminary examinations in other parts of the Colorado Plateau vanadium region. In 1942 detailed geological studies were made o the deposits in the Egnar-Slick Rock district, San Miguel Co., Colo.; 3/ the Carrizo Moungains district, Navajo Indian Reservation, Arizona and New Mexico; 4/ the Placerville district, San Miguel County, Colo. 5/ and the Monticello district, San Juan Co., Utah. 6/ Since May 3, 1943, the Gelogical Survey has guided the Bureau of Mines program of prospecting these deposits in parts of Colorado and Utah.
Date: October 10, 1943
Creator: Fischer, Richard P. & Stokes, William Lee

Memorandum Listing the Areas in Colorado, Utah, Arizona and New Mexico that are Geologically Favorable for Developing Large Reserves of Vanadium Ore by Prospecting

Description: Introduction: Vanadium ore is being mined at many places in western Colorado, southeastern Utah, northeastern Arizona, and northwestern New Mexico (fig. 1). Eight mills in this region produced about 4,300,000 pounds of V2 05 in 1942, representing about 90 percent of the vanadium obtained from domestic sources. Although ore production has mostly exceeded mill capacity since 1937, production during the last half of 1942 averaged only about 19,000 tons or ore a month, whereas the capacity of these mills total about 22,000 tons a month. At the expected rate of ore production, ore stockpiles will be exhausted sometime in 1944, and these mills will then have excess capacity. With more intensive prospecting than now practiced, however, it is believed that sufficient reserves can be indicated to sustain capacity operation of these mills for several years. This memorandum is prepared to specify those areas that are considered most favorable from a geologic standpoint for developing large reserves of vanadium ore by prospecting. It is based on intensive studies by the Geological Survey since 1939 in most of the areas that produce vanadium ore.
Date: April 10, 1943
Creator: Fischer, R. P.

Geology of the Coastal Plain of Georgia

Description: From preface: The manuscript of this report, which is the culmination of field and office studies carried on intermittently s' ice 1914, partly in cooperation with the Geological Survey of Georgia, was completed early in 1938. It was prepared with the expectation that it would form part of a more comprehensive report on the geology of Georgia by several authors, which was intended to accompany a geologic map of the entire State on a scale of 1: 500,000. However, this map without the text was published in 1939 by the Georgia Division of Mines, Mining and Geology. Part of this map is reproduced herein as plate 1 without revision.
Date: 1943
Creator: Cooke, C. Wythe

Manganiferous and Ferruginous Chert in Perry and Lewis Counties, Tennessee

Description: From abstract: Perry and Lewis Counties, east of the Tennessee River, in west-middle Tennessee, are underlain by nearly flat-lying rocks of Paleozoic age, with Mississippian cherty limestones forming the greater part of the surface of the western Highland Rim Plateau ridges. Near the summits of the ridges there is a fairly definite horizon in the chert that contains manganese and iron oxides in varying degrees of concentration. Weathering of the mineralized chert has produced widespread float on the hill slopes and in the beds of small spring branches, and the presence of this float, some of it rich enough for metallurgical manganese ore, has encouraged a search for promising deposits in place. In the present study 52 localities where the mineralized beds crop out or have been prospected were examined.
Date: 1943
Creator: Burchard, Ernest F.

Geology of the Portage Pass Area, Alaska

Description: Abstract: The Portage Pass area is in south-central Alaska, and includes part of the narrow neck of land that joins the Kenai Peninsula with the mainland to the north. This region is in general mountainous, elevations ranging from sea level to more than 4,000 feet on the peaks bordering the area. Several glaciers, all of which are apparently receding, extend into the area. Vegetation, chiefly alder and cottonwood on the valley lowlands and some spruce and hemlock on the lower slopes, extends to an elevation of about 1,000 feet, above which the slopes are bare except for occasional clumps of brush. The bedrock of the entire area is slate, argillite, and graywacke, apparently part of the same great series that extends from the Kenai Peninsula into the Prince William Sound region and is at least in part of Cretaceous age. The only igneous rocks recognized in the area are a few acidic dikes and a small diabase dike. Small, irregular quartz veinlets are widespread. The structure is not only complex but, owing to extensive metamorphism, is in many places obscure. A general northeast strike and steep to vertical dips of both bedding and cleavage planes are the rule, but there appears to be some broad folding along steeply northeast-pitching axes. Although no large faults have been recognized, much movement has occurred along many small faults, shear zones, and bedding planes. All observed faults and shear zones trend northeastward. There are no mines in this area. Some mineralization of quartz veins was noted at a few places, and some prospecting has been done, but no workable deposits are known.
Date: 1943
Creator: Barnes, Farrell F.

The Coso Quicksilver District, Inyo County, California

Description: From abstract: The Coso quicksilver district, which is in the Coso Range, Inyo County, Calif., produced 231 flasks of quicksilver between 1935 and 1939. The quicksilver mineral, cinnabar, was not recognized in the district until 1929, although the hot springs near the deposits have been known since about 1875...The granitic rock on which much of the sinter rests is considerably altered. The cinnabar was deposited as films and grains in open spaces in the sinter, during one stage in a sequence of hot spring activities that still continues. The amount of sinter in the district is estimated to be about 1,800,000 tons. Although the greater part of this does not contain much cinnabar, the total quantity of such material is large enough to be of interest as a low-grade ore.
Date: 1943
Creator: Ross, Clyde P. & Yates, Robert G.