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Biomolecular Materials. Report of the January 13-15, 2002 Workshop

Description: Twenty-two scientists from around the nation and the world met to discuss the way that the molecules, structures, processes and concepts of the biological world could be used or mimicked in designing novel materials, processes or devices of potential practical significance. The emphasis was on basic research, although the long-term goal is, in addition to increased knowledge, the development of applications to further the mission of the Department of Energy.
Date: January 15, 2002
Creator: Alper, M. D. & Stupp, S. I.
Partner: UNT Libraries Government Documents Department


Description: An analytical approach is proposed which allows the bunnup (by fission) of uranium required to cause failure in a uranium dioxide-stainicss steel dispersion fuel element to be calculated. The analysis is developed by assuming the matrix of the fuel eicment to be made up of a uniform, close-packed array of spherical UO/sub 2/ particles, each surrounded by and associated with a hollow stainless steel sphere. Equations are then written for the amount of fission gas released into the stainless steel cavity in terms of the UO/sub 2/ particle size and density and the burnup. The release mechanism is by recoil only, since diffusion is unimportant for the particle sizes and temperatures (<1000 tained F) of interest. The gas atoms recoiled from the UO/sub 2/ particle are assumed to diffuse from the stuinless steel shell into the caviiy. The pressure thus exerted in-side the stuinless steel sphere is computed by the application of a real gas law. A suitable failure criterion for an internally pressunized, heavy-walled metal sphere appears to be when the sphere becomes entirely plastic. An equation for the pressure at failure and displacements of the sphere is written in terms of the UO/sub 2/ loading and the yield strength of the steel. By combination with the previous expressions, the burnup required to cause failure is calculated. Thus, the effects of UO/sub 2/ density and particle size, temperature, strength of the matrix material, and UO/sub 2/ loading on the burnup at failure are predicted by the theory. (auth)
Date: June 15, 1960
Creator: Weir, J. R.
Partner: UNT Libraries Government Documents Department

Mineralogical considerations in leaching of primary copper sulfides at elevated temperatures and pressures

Description: The leaching characteristics of four different ores in sulfuric acid systems pressurized with oxygen are described. The variations in the leaching characteristics between different ores can be largely attributed to differences in mineralogy. Certain gangue mineral alteration phases produced during leaching may trap copper from solution, as well as reduce the porosity of the ore. In addition, the formation of secondary copper sulfides, digenite, and covellite may limit the extraction of copper if the supply of oxygen is restricted to chalcopyrite. Apparently, the key consideration for successful leaching is maximizing the rate of oxidation of the sulfides and, at the same time, minimizing the rate of gangue mineral alteration. This can be accomplished at high oxygen pressures and moderate temperatures (70 to 90$sup 0$C) and low pH (less than or equal to 2.0). The ideal ore mineralogy is one that is low in carbonates and easily altered Fe-Mg minerals such as biotite and hornblende, and one that has acceptable pyrite/chalcopyrite ratios. (auth)
Date: October 15, 1975
Creator: Leach, D.L.
Partner: UNT Libraries Government Documents Department


Description: The general prospects of several radioisotopes are reviewed; the special properties of U/sup 232/ and Th/sup 228/ are poi nted out; and ionium (Th/sup 230/ ) and protactinium target materials are discussed from the sthndpoint of availability and chemical separations processes required for the preparation of U/ sup 232/ and Th/sup 228/. Outlines are given for potential schem es for the separation of U/sup 232/ and Th/sup 228/ from uranium milling pr ocess waste streams and from the irradiation products of Th/sup 230/--Th/sup 232/ mixtures. The high heat generating rates of these potent alpha emitters make them especially suitable for primary consideration as heat sources for small thermoelectric generators. The exceptionally high alpha activity suggests their use in special neutron sources as Ra-Be sources, and they may have sufficiently high neutron generating rates to be in contention with some of the smaller research reactors and experimental neutron producers. (B.O.G.)
Date: December 15, 1959
Creator: Coppinger, E.A. & Rohrmann, C.A.
Partner: UNT Libraries Government Documents Department

15-foot bubble chamber characteristics

Description: Specifications, operation, characteristics, cost, and experience with the NAL 15-ft bubble chamber are described. Beam availability and some experimental proposals are discussed. (WHK)
Date: September 15, 1975
Creator: Huson, F. R.
Partner: UNT Libraries Government Documents Department


Description: The growing interest in the physics of fluidic flow in nanoscale channels, as well as the possibility for high sensitive detection of ions and single molecules is driving the development of nanofluidic channels. The enrichment of charged analytes due to electric field-controlled flow and surface charge/dipole interactions along the channel can lead to enhancement of sensitivity and limits-of-detection in sensor instruments. Nuclear material processing, waste remediation, and nuclear non-proliferation applications can greatly benefit from this capability. Atomic force microscopy (AFM) provides a low-cost alternative for the machining of disposable nanochannels. The small AFM tip diameter (< 10 nm) can provide for features at scales restricted in conventional optical and electron-beam lithography. This work presents preliminary results on the fabrication of nano/microfluidic channels on polymer films deposited on quartz substrates by AFM lithography.
Date: July 15, 2011
Creator: Mendez-Torres, A.; Torres, R. & Lam, P.
Partner: UNT Libraries Government Documents Department


Description: The thermal expansions of commercial uranium dioxide specimens were measured up to the melting point. The linear expansion of dense, normal grain size UO/sub 2/ follows closely the equationi L = L/sub 0/(1 + 6.0 x 10/sup -6/t + 2.0 x 10/sup -9/t/sup 1.7 x 10/sup -12/t/sup 3/). An anomalous expansion was noted in the temperature range 1000 to 1500 deg C. Above 2500 deg C the rapid vaporization and crystal growth of UO/sub 2/ necessitate the application of heating techniques which provide rapid heating and quenching in order to obtain reliable data. The use of solar and arcmelting furnaces for this type of measurement is described. (auth)
Date: April 15, 1959
Creator: Halden, F.A.; Wohlers, H.C. & Reinhart, R.H.
Partner: UNT Libraries Government Documents Department

Kinetics, Stability, and Control. A Selected Bibliography

Description: References to 529 articles on nuclear reactor control, kinetics, and stability published before autumn 1962 are included. Emphasis is on calculations and theory since the references serve as an aid in analyzing the dynamic behavior of SNAP reactor systems. (D.C.W.)
Date: March 15, 1963
Creator: Johnson, R. L.
Partner: UNT Libraries Government Documents Department


Description: The techniques used in sampling, analyzing, and evaluating results for determining hazards from external radiation, airborne radioactive material, radioactive contaminants in mill effluents, and urinary uranium, as applied to the Monticello, Utah, uranium mill, are described. Corrective measures used by National Lead Company, Inc., at the Monticello Mill are described along with the results from later surveys which showed large reductions in the potential radiation hazards. Details are given of the methods used to determine personnel exposures to radioactive and silicosis-producing dusts, potential external radiation hazards and in assaying mill effluents for uranium and radium, assaying urine samples for uranium, as well as the standard operating procedures issued at Monticello to employees for preventing and/or controlling personnel exposures. (auth)
Date: December 15, 1958
Creator: Beverly, R.G. comp. and ed.
Partner: UNT Libraries Government Documents Department

Outreach and Education in the Life Sciences A Case Study of the U.S. Department of Energy National Laboratories

Description: This project was intended to assess the impact of the U.S. Department of Energy’s National Nuclear Security Agency (DOE/NNSA) -sponsored education and outreach activities on the Biological Weapons Convention (BWC) in DOE national laboratories. Key activities focused on a series of pilot education and outreach workshops conducted at ten national laboratories. These workshops were designed to increase awareness of the BWC, familiarize scientists with dual-use concerns related to biological research, and promote the concept of individual responsibility and accountability
Date: March 15, 2010
Creator: Weller, Richard E.; Burbank, Roberta L. & Mahy, Heidi A.
Partner: UNT Libraries Government Documents Department

ZIRCONIUM RESEARCH AND DEVELOPMENT. Progress Report No. 9 for September 15, 1950 to October 15, 1950

Description: A zirconium crystal bar, weighing 29 pounds and 1 5/16 inches in diameter by 8 feet in over-all length, was prepared, using pear-shaped zirconium couples to join the filament to the electrodes. This crystal bar was the largest produced to date in the 16-in.-diam. de Boer unit. The design of the couplings was modified to incorporate improvements indicated by the initial run, and another run is in progress. Binary alloys of Zr and Ni, Cr, and Si, as well as a zirconium alloy containing Fe, Al, and Si, were prepared for use as feed material in the small pyrex de Boer bulbs. The transfer of these elements from the feed to the crystal bar is being investigated. The rate of deposition and the type of crystal structure obtained with additions of various amounts of iodine are being studied. (auth)
Date: October 15, 1950
Creator: Bulkowski, H.H.; Sebenick, J.J.; Campbell, I.E. & Gonser, B.W.
Partner: UNT Libraries Government Documents Department


Description: Promethium is purified from inactive and radioactive long-lived fission- produced rare earths by the use of Dowex 50 or Nalcite HCR cation exchangers and organic eluants. Americium and promethium, having hydrated ionic radii of the same size, are contained in the same fraction of the eluate. Promethium is purified from americium by adsorbing both elements on Dowex 1 (thiocyanate form) and eluting promethium from the resin with ammonium thiocyanate solution. Equllibrium studies were made in order to determine distribution coefficients of the long-lived radioactive rare earths. Elution curves based on analyses of solutions removed from anion and cation exchangers verify the relative values of the distribution coefficients. From Dowex 1 resin, rare earths 58 through 63 elute with ammonium thiocyanate in the order of increasing atomic number. Conditions are established for the expansion of the present 50- to 100-curie- level processing to levels of 1000 to 5000 curies. (auth)
Date: March 15, 1960
Creator: Pressly, R.S.
Partner: UNT Libraries Government Documents Department


Description: Dvelopmental activities are reported on the EBWR, Borax-V, ZPR-KI, AFSR, EBR-I, EBR-II, and FARET. Progress is also reported in the area of general reactor technology in applied reactor physice, reactor fuel development, reactor materials development, heat engineering, and chemical separations. Information on advanced research and development is included concerning the AARR, undersea applications of nuclear power, conduction-cooled reactor heat sources, and direct conversion. Nuclear safety work is reported on TREAT, thermal reactor safety, and fast reactor safety. (J.R.D.)
Date: December 15, 1962
Partner: UNT Libraries Government Documents Department