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Description: This is a report to demonstrate use of Non-Scaling Fixed-Field Alternating-Gradient (FFAG) accelerators [1] in acceleration of partially stripped ions of Uranium-238 for Rare Isotopes Production. This example assumes a beam final energy of 500 MeV/u with an average beam output current of 1 {micro}A-particle and a beam average power of 120 kWatt.
Date: June 26, 2006
Partner: UNT Libraries Government Documents Department


Description: We explore the possibility of using two non-scaling FFAG accelerators for a high power heavy-ion driver as an alternative to a superconducting Linac. Ions of Uranium 238 are accelerated to a kinetic energy of 400 MeVIu and a total power of 400 kWatt. Different modes of acceleration have been studied: at 1 and 10 kHz repetition rate, and for Continuous Wave production. The following is a summary of the study. More details of the study can be found in reference 2.
Date: June 25, 2007
Partner: UNT Libraries Government Documents Department

Power production and ADS

Description: We describe the power production process in Accelerator Driven Sub-critical systems employing Thorium-232 and Uranium-238 as fuel and examine the demands on the power of the accelerator required.
Date: March 1, 2010
Creator: Raja, Rajendran
Partner: UNT Libraries Government Documents Department

Limitations on the precision of 238U/235U measurements and implications for environmental monitoring

Description: The ability to determine the isotopic composition of uranium in environmental samples is an important component of the International Atomic Energy Agency`s (IAEA) safeguards program, and variations in the isotopic ratio {sup 238}U/{sup 235}U provide the most direct evidence of isotopic enrichment activities. The interpretation of observed variations in {sup 238}U/{sup 235}U depends on the ability to distinguish enrichment from instrumental biases and any variations occurring in the environment but not related to enrichment activities. Instrumental biases that have historically limited the accuracy of {sup 238}U/{sup 235}U determinations can be eliminated by the use of the {sup 233}U/{sup 236}U double-spike technique. With this technique, it is possible to determine the {sup 238}U/{sup 235}U in samples to an accuracy equal to the precision of the measurement, ca. 0.1% for a few 10`s of nanograms of uranium. Given an accurate determination of {sup 238}U/{sup 235}U, positive identification of enrichment activities depends on the observed value being outside the range of {sup 238}U/{sup 235}U`s expected as a result of natural or environmental variations. Analyses of a suite of soil samples showed no variation beyond 0.2% in {sup 238}U/{sup 235}U.
Date: August 1, 1997
Creator: Russ III, G.P.
Partner: UNT Libraries Government Documents Department

Spatial variations of particle scavenging rates within the central and northern Adriatic Sea: use of U--Th disequilibria

Description: Dissolved and particlulate Thorium-234 ({sup 234}Th) were measured in near surface waters from the Central and Northern Adriatic Sea in order to gain an insight into the intensity and variability of active scavenging and particle removal processes. Dissolved {sup 234}Th to Uranium-238 ({sup 238}U) activity ratios vary from 0.21 to 0.75 and clearly imply that {sup 234}Th is being actively scavenged from sea water on a timescale of <3 months. The scavenging rate of dissolved {sup 234}Th with respect to scavenging onto particles appears to correlate with primary productivity measurements. Scavenging and rapid removal of particulate {sup 234}Th from the water column is best explained by a mechanism of zooplankton grazing and fecal pellet production. At one sight in the Jabuka Pit, particulate {sup 234}Th residence times below the pycnocline are long (30-40 days) suggesting that particles are being more readily recycled at these depths. By comparison, in a seawater profile collected near the Po outflow region, {sup 234}Th is depleted with respect to {sup 238}U through the entire water column. We conclude from this assessment that particles in waters near the Po River outflow will be more efficiently transported to bottom sediments compared with those in deeper waters over the Jabuka Pit.
Date: April 1, 1998
Creator: Hamilton, T. F.
Partner: UNT Libraries Government Documents Department

Demonstration recommendations for accelerated testing of concrete decontamination methods

Description: A large number of aging US Department of Energy (DOE) surplus facilities located throughout the US require deactivation, decontamination, and decommissioning. Although several technologies are available commercially for concrete decontamination, emerging technologies with potential to reduce secondary waste and minimize the impact and risk to workers and the environment are needed. In response to these needs, the Accelerated Testing of Concrete Decontamination Methods project team described the nature and extent of contaminated concrete within the DOE complex and identified applicable emerging technologies. Existing information used to describe the nature and extent of contaminated concrete indicates that the most frequently occurring radiological contaminants are {sup 137}Cs, {sup 238}U (and its daughters), {sup 60}Co, {sup 90}Sr, and tritium. The total area of radionuclide-contaminated concrete within the DOE complex is estimated to be in the range of 7.9 {times} 10{sup 8} ft{sup 2}or approximately 18,000 acres. Concrete decontamination problems were matched with emerging technologies to recommend demonstrations considered to provide the most benefit to decontamination of concrete within the DOE complex. Emerging technologies with the most potential benefit were biological decontamination, electro-hydraulic scabbling, electrokinetics, and microwave scabbling.
Date: December 1, 1995
Creator: Dickerson, K.S.; Ally, M.R.; Brown, C.H.; Morris, M.I. & Wilson-Nichols, M.J.
Partner: UNT Libraries Government Documents Department


Description: Information is presented in tabular form on the contributions of the individual resonances to the resonance integrals in U and Th. The cases considered are for isolated cylindrical rods and involve U/sup 238/, U/sup 238/O/ sub 2/, Th/ sup 232/, and Th/sup 232/O/sub 2/ (M.C.G.)
Date: October 26, 1961
Creator: Nordheim, L.W.
Partner: UNT Libraries Government Documents Department


Description: ABS>The measurable properties of a critical assembly (e.g.. fission, capture, and leakage rates; neutron-per-fission ratios; bare/Cd-covered reaction rate of-atios; danger eoefficients; etc.), whose judicious use completely defines tbcneutron economy in the assembly, are discussed. Require ments regarding the internal consisteney of these of:deasured quantities are reviewed. lt is concluded that theoretical analysis of the assembly must both reproduce the gross experimental results and reflect the internal consistency of the data. Only thermal systems fueled with U/sup 235/ and U/sup 238/ are considered. (T.F.H.)
Date: January 1, 1962
Creator: Kelber, C.N.
Partner: UNT Libraries Government Documents Department


Description: The theory is presented in detail of an activation method for measuring the ratio of U/sup 238/ absorptions to U/sup 235/ fissions in a nuclear reactor. The origin of the activities is discussed, the equations are given for interpretation of the measurements, and the expected counting rates are computed for a typical experiment in the EGCR. (auth)
Date: August 10, 1962
Creator: Preskitt, C.A.
Partner: UNT Libraries Government Documents Department


Description: Fixed-Field Alternating-Gradient (FFAG) accelerators are being proposed as an alternative to Super-conducting Linacs (SCL), Rapid-Cycling Synchrotrons (RCS) and Cyclotrons for the acceleration of very intense Heavy-Ion and Proton beams in the medium energy range. One application is the acceleration of ions of Uranium-238 to an energy of 400 MeV/u, and the average power of 400 kWatt, and the other a 1-GeV Proton Driver with an average beam power of 10 MWatt. One or two FFAG rings are needed for acceleration of both beams. They adopt a Non-Scaling Lattice (NSL) to reduce the size and the cost of the accelerator. The continuous wave (CW) mode of operation is achieved with the method of Harmonic Number Jump (HNJ).
Date: October 1, 2007
Creator: RUGGIERO,A.
Partner: UNT Libraries Government Documents Department

Independent Verification Final Summary Report for the David Witherspoon, Inc. 1630 Site Knoxville, Tennessee

Description: The primary objective of the independent verification was to determine if BJC performed the appropriate actions to meet the specified “hot spot” cleanup criteria of 500 picocuries per gram (pCi/g) uranium-238 (U-238) in surface soil. Specific tasks performed by the independent verification team (IVT) to satisfy this objective included: 1) performing radiological walkover surveys, and 2) collecting soil samples for independent analyses. The independent verification (IV) efforts were designed to evaluate radioactive contaminants (specifically U-238) in the exposed surfaces below one foot of the original site grade, given that the top one foot layer of soil on the site was removed in its entirety.
Date: April 29, 2009
Creator: Weaver, P.C.
Partner: UNT Libraries Government Documents Department

Report for Batch Leach Analyses on Sediments at 100-HR-3 Operable Unit, Boreholes C7620, C7621, C7622, C7623, C7626, C7627, C7628, C7629, C7630, and C7866. Revision 1.

Description: This is a revision to a previously released report. This revision contains additional analytical results for the sample with HEIS number B2H4X7. Between November 4, 2010 and October 26, 2011 sediment samples were received from 100-HR-3 Operable Unit for geochemical studies. The analyses for this project were performed at the 331 building located in the 300 Area of the Hanford Site. The analyses were performed according to Pacific Northwest National Laboratory (PNNL) approved procedures and/or nationally recognized test procedures. The data sets include the sample identification numbers, analytical results, estimated quantification limits (EQL), and quality control data. The preparatory and analytical quality control requirements, calibration requirements, acceptance criteria, and failure actions are defined in the on-line QA plan 'Conducting Analytical Work in Support of Regulatory Programs' (CAW). This QA plan implements the Hanford Analytical Services Quality Assurance Requirements Documents (HASQARD) for PNNL. Samples were received with a chain of custody (COC) and were analyzed according to the sample identification numbers supplied by the client. All Samples were refrigerated upon receipt until prepared for analysis. All samples were received with custody seals intact unless noted in the Case Narrative. Holding time is defined as the time from sample preparation to the time of analyses. The prescribed holding times were met for all analytes unless noted in the Case Narrative. All reported analytical results meet the requirements of the CAW or client specified SOW unless noted in the case narrative. Due to the requirements of the statement of work and sampling events in the field, the 28 day and the 48 hr requirements cannot be met. The statement of work requires samples to be selected at the completion of the borehole. It is not always possible to complete a borehole and have the samples shipped to the laboratory within the hold time ...
Date: April 25, 2012
Creator: Lindberg, Michael J.
Partner: UNT Libraries Government Documents Department

Determination of 235U/238U Ratio on Urine by ICP-MS

Description: LLNL Internal Dosimetry Program - The new procedure satisfies the requirement to determine {sup 235}U/{sup 238}U ratio in bioassay urine samples. MDA - The L{sub C} and MDA{sub 95} for {sup 235}U are well below the required detection limit of 0.00035 {mu}g/L. Turn around time - Analysis of 10 samples plus 2 QCs can be completed in one work day (8 hours).
Date: October 19, 2011
Creator: Collins, L; Gobaleza, A; Langston, R; Radev, R; Than, C; Wong, C et al.
Partner: UNT Libraries Government Documents Department