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Analytical studies of the estimation of beryllium oxide in beryllium metal

Description: From abstract: The estimation of beryllium oxide in beryllium metal depending on the differential solubilities of the two material in dilute hydrochloric acid is presented. The results compare favorably with the present beryllium chloride volatilization procedure. Alternate methods are described, and the limitations and possible errors are discussed.
Date: April 17, 1951
Creator: Rynasiewicz, Joseph
Partner: UNT Libraries Government Documents Department

Development of Biomarkers for Chronic Beryllium Disease in Mice

Description: Beryllium is a strategic metal, indispensable for national defense programs in aerospace, telecommunications, electronics, and weaponry. Exposure to beryllium is an extensively documented occupational hazard that causes irreversible, debilitating granulomatous lung disease in as much as 3 - 5% of exposed workers. Mechanistic research on beryllium exposure-disease relationships has been severely limited by a general lack of a sufficient CBD animal model. We have now developed and tested an animal model which can be used for dissecting dose-response relationships and pathogenic mechanisms and for testing new diagnostic and treatment paradigms. We have created 3 strains of transgenic mice in which the human antigen-presenting moiety, HLA-DP, was inserted into the mouse genome. Each mouse strain contains HLA-DPB1 alleles that confer different magnitude of risk for chronic beryllium disease (CBD): HLA-DPB1*0401 (odds ratio = 0.2), HLA-DPB1*0201 (odds ratio = 15), HLA-DPB1*1701 (odds ratio = 240). Our preliminary work has demonstrated that the *1701 allele, as predicted by human studies, results in the greatest degree of sensitization in a mouse ear swelling test. We have also completed dose-response experiments examining beryllium-induced lung granulomas and identified susceptible and resistant inbred strains of mice (without the human transgenes) as well as quantitative trait loci that may contain gene(s) that modify the immune response to beryllium. In this grant application, we propose to use the transgenic and ├é┬śnormal inbred strains of mice to identify biomarkers for the progression of beryllium sensitization and CBD. To achieve this goal, we propose to compare the sensitivity and accuracy of the lymphocyte proliferation test (blood and bronchoalveolar lavage fluid) with the ELISPOT test in the three HLA-DP transgenic mice strains throughout a 6 month treatment with beryllium particles. Because of the availability of high-throughput proteomics, we will also identify changes in potential protein biomarkers in beryllium-treated mice. We will correlate ...
Date: January 25, 2013
Creator: Gordon, Terry
Partner: UNT Libraries Government Documents Department

Impact of HFIR LEU Conversion on Beryllium Reflector Degradation Factors

Description: An assessment of the impact of low enriched uranium (LEU) conversion on the factors that may cause the degradation of the beryllium reflector is performed for the High Flux Isotope Reactor (HFIR). The computational methods, models, and tools, comparisons with previous work, along with the results obtained are documented and discussed in this report. The report documents the results for the gas and neutronic poison production, and the heating in the beryllium reflector for both the highly enriched uranium (HEU) and LEU HFIR configurations, and discusses the impact that the conversion to LEU may have on these quantities. A time-averaging procedure was developed to calculate the isotopic (gas and poisons) production in reflector. The sensitivity of this approach to different approximations is gauged and documented. The results show that the gas is produced in the beryllium reflector at a total rate of 0.304 g/cycle for the HEU configuration; this rate increases by ~12% for the LEU case. The total tritium production rate in reflector is 0.098 g/cycle for the HEU core and approximately 11% higher for the LEU core. A significant increase (up to ~25%) in the neutronic poisons production in the reflector during the operation cycles is observed for the LEU core, compared to the HEU case, for regions close to the core s horizontal midplane. The poisoning level of the reflector may increase by more than two orders of magnitude during long periods of downtime. The heating rate in the reflector is estimated to be approximately 20% lower for the LEU core than for the HEU core. The decrease is due to a significantly lower contribution of the heating produced by the gamma radiation for the LEU core. Both the isotopic (gas and neutronic poisons) production and the heating rates are spatially non-uniform throughout the beryllium reflector volume. ...
Date: October 1, 2013
Creator: Ilas, Dan
Partner: UNT Libraries Government Documents Department

Some properties of beryllium oxide and beryllium oxide - columbium ceramals

Description: High-temperature tensile and thermal-shock investigations were conducted on beryllium oxide and beryllium oxide plus columbium metal additions. X-ray diffraction and metallographic results are given. The tensile strength of 6150 pounds per square inch for beryllium oxide at 1800 degrees F compared favorably with the zirconia bodies previously tested. Additions of 2, 5, 8, 10, 12, and 15 percent by weight of columbium metal failed to improve the shock resistance over that of pure beryllium oxide.
Date: March 2, 1951
Creator: Robards, C. F. & Gangler, J. J.
Partner: UNT Libraries Government Documents Department

Geochemistry of Beryllium

Description: From abstract: This is a review, with annotated bibliography, of the mode of occurrence of the element beryllium. It is not a list of specific ore deposits, but a summary of the types of the types of minerals and rocks in which beryllium has been reported to occur. In addition, the unpublished spectrographic studies of the Geological Survey on mill products are summarized, and data are given on domestic production and reserves and on foreign production.
Date: June 1946
Creator: Fleischer, Michael & Cameron, E. N.
Partner: UNT Libraries Government Documents Department

Determination of Natural Beryllium (Be) in Soil and Swipe Samples Utilizing Yttrium/Beryllium Ratio

Description: 1. Objective: A method to determine whether beryllium (Be) components in surface swipe samples are from a natural source is needed. 2. Methods: Soil samples and surface swipes from area facilities were analyzed for marker elements to identify source pathways for beryllium (Be). To be useful, the natural marker element must be present at reasonably consistent levels across the site, must correlate with the Be concentration, and not have the potential to be present from non-natural sources. 3. Results: The research on marker elements used to identify source pathways for beryllium (Be) concentrations demonstrates a clear correlation between Be and yttrium (Y) in natural soils on the Nevada National Security Site. The Y/Be ratio is proposed as a method to characterize the source of Be in soil and surface swipe samples and to aid in recommendations for follow up actions. Swipe samples are analyzed using an ICP/MS method and compared with results from soil samples. Natural soil constituent levels and the Y/Be Ratio range is determined for the occupied and historical facilities and surrounding areas. Y/Be ratios within the statistical range established indicate the Be is from a natural source. Y/Be ratios lower than this range indicate the presence of another Be source, and may then be correlated to alloy, ceramic, or other operational sources by the ratios of copper, nickel, cobalt, uranium, and/or niobium. Example case studies of evaluations of buildings with historical operational beryllium usage, current ongoing technical processes, and heavy equipment used in large building demolitions are included demonstrating the value of the ratio approach. 4. Conclusions: This differentiation is valuable as there is no known correlation between natural beryllium in soil and beryllium disease.
Date: September 30, 2010
Partner: UNT Libraries Government Documents Department

The Enhancing Effect of the Inhalation of Hydrogen Fluoride Vapor on Beryllium Sulfate Poisoning in Animals

Description: Report investigating the possible relationship between fluoride and beryllium toxicity by exposing rats to either beryllium sulfate mist and/or hydrogen fluoride vapor. Materials, experimental methods, and results are described. Bibliography begins on page 23.
Date: 1949
Creator: Stokinger, Herbert E. (Herbert Ellsworth), 1909-; Ashenburg, N. J.; DeVoldre, J.; Scott, J. K. & Smith, F. A.
Partner: UNT Libraries Government Documents Department

New England Beryllium Investigations

Description: Report issued by the Bureau of mines over studies conducted on beryllium deposits in New England. Evaluations of the deposits are presented and discussed. This report includes tables, maps, illustrations, and photographs.
Date: 1968
Creator: Barton, William R. & Goldsmith, Carl E.
Partner: UNT Libraries Government Documents Department

Beryllia and Beryllia-Beryllium Bodies for Moderating Cores in Fuel Elements

Description: From introduction: This report presents the results of the two phases of the work: study of the compatibility of beryllia bodies with a coating material, molybdenum; and studies of beryllia-beryllium body fabrication.
Date: July 31, 1952
Creator: Long, R. E.; Duckworth, W. H.; Saller, Henry A.; Stacy, J. T.; Miller, R. A. & Schofield, H. Z.
Partner: UNT Libraries Government Documents Department

Experiments on the Effect of Atomic Electrons on the DecayConstant of Be7 II.

Description: A comparison of the decay constants of Be{sup 7} in beryllium oxide and in beryllium fluoride has given {lambda}{sub BeO}-{lambda}{sub BeF{sub 2}} = (+1.375 {+-} 0.053)10{sup -3}{lambda}{sub BeO} thus showing a definite effect of the chemical binding on the radioactive decay constant.
Date: June 15, 1949
Creator: Leininger, R.F.; Segre, E. & Wiegand, C.
Partner: UNT Libraries Government Documents Department

LITERATURE SURVEY OF GASES IN BERYLLIUM. Report to Wright Air Development Division

Description: Structural and thermodynamic properties of beryllium, beryllium-oxygen systems, beryllium-nitrogen systems, and beryllium-hydrogen systems as determined by various researchers are surveyed. Diffusion properties, reaction kinetics, and vapor pressures are given where they were available. 44 references. (D.C.W.)
Date: January 17, 1961
Creator: Pemsler, J.P. & Anderson, R.W.
Partner: UNT Libraries Government Documents Department

Implications for the Cryogenic Fielding of Leaking Beryllium Capsules

Description: In this paper we show that the ambient temperature measured leakage time constant, {tau}{sub RT}, is related to the leakage at cryogenic temperature, R{sub C}, by R{sub C}= 0.23{rho}{sub DT}V{sub sh}/ {tau}{sub RT} where {rho}{sub DT} is the density of cryogenic DT vapor, and V{sub sh} is the internal volume of the shell. We then calculate the size of voids that may result from leakage at the Be/DT interface, depending upon the number of leakage sites and {tau}{sub RT}. Even for the slowest leakers the potential void growth is excessive. Reasons that voids have not been seen in DT layering experiments to date include the lack of a technique to see isolated micronish bubbles, however possible mechanisms preventing void formation are also discussed.
Date: February 20, 2007
Creator: Cook, R
Partner: UNT Libraries Government Documents Department

The elevated temperature tensile properties of S-200E commercially pure beryllium

Description: Experiments were performed at 300-100 C in longitudinal and transverse orientations at quasi-static strain rate 5.5 {times} 10{sup {minus}4}s{sup {minus}1}. Results show that the stress-strain curve is smooth, without yield points or serrations. Yield stress and ultimate tensile stress decrease monotonically with temperature. Similar strengths were measured for both orientations. Failure elongation vs temperature is complex.
Date: March 1, 1995
Creator: Henshall, G.A.; Torres, S.G. & Hanafee, J.E.
Partner: UNT Libraries Government Documents Department


Description: No abstract.<><DSN>16:004155<ABS>No abstract.<><DSN>16:004156<ABS>Nitrosylium hexafluoroniolybdate(V) and nitrosylium hexafluorouranate(V) were prepared and characterized. These compounds were prepared by the reaction of nitric oxide with the respective hexafluoride. Nitric oxide did not react with tungsten hexafliioride. Nitrous oxide was found to be unreactive toward molybdenum, tungsten, and uranium hexafluorides. (auth)
Date: September 1, 1961
Creator: Stewart, J C & Pyatt, Jr, K D
Partner: UNT Libraries Government Documents Department


Description: Spherical particles of beryllium oxide containing and enclosing UO/sub 2/ particles (-1O micron) were prepared by dispersing a suspension of UO/sub 2/ in a concentrated viscous solution of a basic beryllium saIt in a liquid organic medium, drying, and firing. The spheres produced were porous and would require densification to make the beryllium oxide protective to the UO/sub 2/. Precipitation of beryllium hydroxide or carbonate on UO/sub 2/ particles suspended in solutions of beryllium salts under various conditions produced no actual coating of the UO/sub 2/ particles. (auth)
Date: May 1, 1962
Creator: McDowell, W.J.
Partner: UNT Libraries Government Documents Department