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Description: The realization of a paradigm chaotic system, namely the harmonically driven oscillator, in the quantum domain using cold trapped ions driven by lasers is theoretically investigated. The simplest characteristics of regular and chaotic dynamics are calculated. The possibilities of experimental realization are discussed.
Date: September 3, 2002
Partner: UNT Libraries Government Documents Department

Flow patterns in sodium cold trap crystallizers

Description: From joint meeting of the American Nuclear Society and the Atomic Industrial Forum and Nuclear Energy Exhibition; San Francisco, California, USA (11 Nov 1973). A simple. inexpensive flow distribution device is required for sodium cold trap crystallizers. The use of inlet mixing nozzles to promote uniform crystallizer flow distribution was investigated. Usually, the inlet to the crystallizer is a straight pipe entering at one point of the annulus. The work compared the conventional inlet nozzle to a 90 deg elbow pointing horizontally at the top of the annulus. The nozzle length between the bend and the outlet of the nozzle was two pipe diameters. The nozzle diameter was the same as the crystallizer inlet pipe. The flow patterns were evaluated using a water model of the crystallizer tank. The results indicate that modification of the crystallizer inlet pipe to a 90 deg elbow directed tangentially on the annulus centerline will produce signficant improvement of flow distribution and should provide increased crystallizer volume effectiveness. The improvement is more pronounced at low flow rates than at high flow rates. (auth)
Date: October 1, 1973
Creator: Lester, D.H. & Bloom, G.R.
Partner: UNT Libraries Government Documents Department


Description: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The project objectives were to explore theoretically various aspects of nonlinear atom optics effects in cold-atom waves and traps. During the project a major development occurred the observation, by as many as a dozen experimental groups, of Bose-Einstein condensation (BEC) in cold-atom traps. This stimulated us to focus our attention on those aspects of nonlinear atom optics relating to BEC, in addition to continuing our work on a nonequilibrium formalism for dealing with the interaction of an electromagnetic field with multi-level atomic systems, allowing for macroscopic coherence effects such as BEC. Studies of several problems in BEC physics have been completed or are near completion, including the suggested use of external electric fields to modify the nature of the interatomic interaction in cold-atom traps; properties of two-phase condensates; and molecular loss processes associated with BEC experiments involving a so-called Feshbach resonance.
Date: July 1, 1999
Creator: MILONNI, T.; CSANAK, G. & AL, ET
Partner: UNT Libraries Government Documents Department

Decoherence bounds on the capabilities of cold trapped ion quantum computers

Description: Using simple physical arguments we investigate the capabilities of a quantum computer based on cold trapped ions of the type recently proposed by Cirac and Zoller. From the limitations imposed on such a device by decoherence due to spontaneous decay, laser phase coherence times, ion heating and other possible sources of error, we derive bounds on the number of laser interactions and on the number of ions that may be used. As a quantitative measure of the possible performance of these devices, the largest number which may be factored using Shor`s quantum factoring algorithm is determined for a variety of species of ion.
Date: May 1, 1997
Creator: James, D.F.V.; Hughes, R.J. & Knill, E.H.
Partner: UNT Libraries Government Documents Department

Uranium hexafluoride: A manual of good handling practices. Revision 7

Description: The United States Enrichment Corporation (USEC) is continuing the policy of the US Department of Energy (DOE) and its predecessor agencies in sharing with the nuclear industry their experience in the area of uranium hexafluoride (UF{sub 6}) shipping containers and handling procedures. The USEC has reviewed Revision 6 or ORO-651 and is issuing this new edition to assure that the document includes the most recent information on UF{sub 6} handling procedures and reflects the policies of the USEC. This manual updates the material contained in earlier issues. It covers the essential aspects of UF{sub 6} handling, cylinder filling and emptying, general principles of weighing and sampling, shipping, and the use of protective overpacks. The physical and chemical properties of UF{sub 6} are also described. The procedures and systems described for safe handling of UF{sub 6} presented in this document have been developed and evaluated during more than 40 years of handling vast quantities of UF{sub 6}. With proper consideration for its nuclear properties, UF{sub 6} may be safely handled in essentially the same manner as any other corrosive and/or toxic chemical.
Date: January 1, 1995
Partner: UNT Libraries Government Documents Department

Ultra-cold molecule production.

Description: The production of Ultra-cold molecules is a goal of many laboratories through out the world. Here we are pursuing a unique technique that utilizes the kinematics of atomic and molecular collisions to achieve the goal of producing substantial numbers of sub Kelvin molecules confined in a trap. Here a trap is defined as an apparatus that spatially localizes, in a known location in the laboratory, a sample of molecules whose temperature is below one degree absolute Kelvin. Further, the storage time for the molecules must be sufficient to measure and possibly further cool the molecules. We utilize a technique unique to Sandia to form cold molecules from near mass degenerate collisions between atoms and molecules. This report describes the progress we have made using this novel technique and the further progress towards trapping molecules we have cooled.
Date: December 1, 2005
Creator: Ramirez-Serrano, Jamie; Chandler, David W.; Strecker, Kevin & Rahn, Larry A.
Partner: UNT Libraries Government Documents Department

Fuel conditioning facility electrorefiner cadmium vapor trap operation.

Description: Processing sodium-bonded spent nuclear fuel at the Fuel Conditioning Facility at Argonne National Laboratory-West involves an electrometallurgical process employing a molten LiCl-KCl salt covering a pool of molten cadmium. Previous research has shown that the cadmium dissolves in the salt as a gas, diffuses through the salt layer and vaporizes at the salt surface. This cadmium vapor condenses on cool surfaces, causing equipment operation and handling problems. Using a cadmium vapor trap to condense the cadmium vapors and reflux them back to the electrorefiner has mitigated equipment problems and improved electrorefiner operations.
Date: May 4, 1998
Creator: Vaden, D. E.
Partner: UNT Libraries Government Documents Department

Occupational Radiation Exposure Analysis of US ITER DCLL TBM

Description: This report documents an Occupational Radiation Exposure (ORE) analysis that was performed for the US International Thermonuclear Experimental Reactor (ITER) Dual Coolant Lead Lithium (DCLL) Test Blanket Module (TBM). This analysis was performed with the QADMOD dose code for anticipated maintenance activities for this TBM concept and its ancillary systems. The QADMOD code was used to model the PbLi cooling loop of this TBM concept by specifying gamma ray source terms that simulated radioactive material within the piping, valves, heat exchanger, permeator, pump, drain tank, and cold trap of this cooling system. Estimates of the maintenance tasks that will have to be performed and the time required to perform these tasks where developed based on either expert opinion or on industrial maintenance experience for similar technologies. This report details the modeling activity and the calculated doses for the maintenance activities envisioned for the US DCLL TBM.
Date: August 1, 2007
Creator: Merrill, Brad J; Cadwallader, Lee C & Dagher, Mohamad
Partner: UNT Libraries Government Documents Department

Sodium technology. Progress report, July-September 1980

Description: This report presents a quarterly summary of progress made in the areas of radioactivity control technology and sodium systems technology. Accomplishments during this period include: radionuclide trap operation in EBR-2; a 8000-h test of radionuclide deposition into 304 and 316 ss; radioactivity surveillance in FFTF HTS; inspection of deposition sampler from EBR-2; sodium frost tests; cold trap testing; effects of mesh packing on natural convection in cold trap crystallizer; and fuel failure monitoring in FFTF and EBR-2. (DLC)
Date: December 1, 1980
Creator: Atwood, J.M. (comp.)
Partner: UNT Libraries Government Documents Department

Corrosion performance of advanced structural materials in sodium.

Description: This report gives a description of the activities in design, fabrication, construction, and assembling of a pumped sodium loop for the sodium compatibility studies on advanced structural materials. The work is the Argonne National Laboratory (ANL) portion of the effort on the work project entitled, 'Sodium Compatibility of Advanced Fast Reactor Materials,' and is a part of Advanced Materials Development within the Reactor Campaign. The objective of this project is to develop information on sodium corrosion compatibility of advanced materials being considered for sodium reactor applications. This report gives the status of the sodium pumped loop at Argonne National Laboratory, the specimen details, and the technical approach to evaluate the sodium compatibility of advanced structural alloys. This report is a deliverable from ANL in FY2010 (M2GAN10SF050302) under the work package G-AN10SF0503 'Sodium Compatibility of Advanced Fast Reactor Materials.' Two reports were issued in 2009 (Natesan and Meimei Li 2009, Natesan et al. 2009) which examined the thermodynamic and kinetic factors involved in the purity of liquid sodium coolant for sodium reactor applications as well as the design specifications for the ANL pumped loop for testing advanced structural materials. Available information was presented on solubility of several metallic and nonmetallic elements along with a discussion of the possible mechanisms for the accumulation of impurities in sodium. That report concluded that the solubility of many metals in sodium is low (<1 part per million) in the temperature range of interest in sodium reactors and such trace amounts would not impact the mechanical integrity of structural materials and components. The earlier report also analyzed the solubility and transport mechanisms of nonmetallic elements such as oxygen, nitrogen, carbon, and hydrogen in laboratory sodium loops and in reactor systems such as Experimental Breeder Reactor-II, Fast Flux Test Facility, and Clinch River Breeder Reactor. Among the ...
Date: May 16, 2012
Creator: Natesan, K.; Momozaki, Y.; Li, M. & Rink, D.L. (Nuclear Engineering Division)
Partner: UNT Libraries Government Documents Department

Cold trap requirements for PHTS and IHTS sodium purification

Description: Cold trap requirements for the Primary Heat Transfer System (PHTS) and the Intermediate Heat Transfer System (IHTS) are defined. The bases for these requirements are (1) maintaining concentrations of oxygen and hydrogen within given limits, (2) controlling the transport of tritium by coprecipitating it in cold traps together with hydrogen, and (3) providing the necessary volume capacity for collecting impurities. It is concluded that the 60 gpm, FFTF Type I, NaK cooled, cold trap will satisfy the PHTS requirements. For each of the IHTS loops a single, 60 gpm, cold trap is required; and an aircooled trap similar to the FFTF Type I design except for a 3-foot longer crystallizer section has been chosen for this service.
Date: May 31, 1974
Creator: Sletten, H.L.
Partner: UNT Libraries Government Documents Department

Interim report on cold trap alternatives, sodium technology

Description: This is an interim report on the modifications which are being made to an existing sodium loop so that a new method of removing hydrogen from sodium can be evaluated in a flowing sodium system. Some preliminary results on the performance of this type of cold trap alternative in a static sodium system are reported. Some tentative reactor design parameters for this type of getter device are presented based on the static test results. The life of such a unit is calculated to be substantially greater than that of a cold trap of equal volume.
Date: September 18, 1978
Creator: Hill, E.F.
Partner: UNT Libraries Government Documents Department

Thermal and hydraulic analyses of the System 81 cold traps

Description: Thermal and hydraulic analyses of the System 81 Type I and II cold traps were completed except for thermal transients analysis. Results are evaluated, discussed, and reported. Analytical models were developed to determine the physical dimensions of the cold traps and to predict the performance. The FFTF cold trap crystallizer performances were simulated using the thermal model. This simulation shows that the analytical model developed predicts reasonably conservative temperatures. Pressure drop and sodium residence time calculations indicate that the present design will meet the requirements specified in the E-Specification. Steady state temperature data for the critical regions were generated to assess the magnitude of the thermal stress.
Date: June 15, 1977
Creator: Kim, K.
Partner: UNT Libraries Government Documents Department

Waste Generated from LMR-AMTEC Reactor Concept

Description: The candidate Liquid Metal Reactor-Alkali Metal Thermal -to- Electric Converter (LMR-AMTEC) is considered to be the first reactor that would use pure liquid potassium as a secondary coolant, in which potassium vapor aids in the conversion of thermal energy to electric energy. As with all energy production, the thermal generation of electricity produces wastes. These wastes must be managed in ways which safeguard human health and minimize their impact on the environment. Nuclear power is the only energy industry, which takes full responsibility for all its wastes. Based on the candidate design of the LMR-AMTEC components and the coolant types, different wastes will be generated from LMR. These wastes must be classified and characterized according to the U.S. Code of Federal Regulation, CFR. This paper defines the waste generation and waste characterization from LMR-AMTEC and reviews the applicable U.S. regulations that govern waste transportation, treatment, storage and final disposition. The wastes generated from LMR-AMTEC are characterized as: (1) mixed waste which is generated from liquid sodium contaminated by fission products and activated corrosion products; (2) hazardous waste which is generated from liquid potassium contaminated by corrosion products; (3) spent nuclear fuel; and (4) low-level radioactive waste which is generated from the packing materials (e.g. activated carbon in cold trap and purification units). The regulations and management of these wastes are summarized in this paper.
Date: February 25, 2003
Creator: Hasan, Ahmed; Mohamed, Yasser, T. & Mohammaden, Tarek, F.
Partner: UNT Libraries Government Documents Department

Experiments on cold-trap regeneration by NaH decomposition. [LMFBR]

Description: Cold-trap regeneration may be very important in future LMFBRs because of the expected high hydrogen source from the steam generators. This hydrogen precipitates as NaH in the cold trap and may fill the trap within one year of operation. Several methods of cold-trap regeneration were considered, but the simplest and least expensive appears to be decomposition of NaH under vacuum at elevated temperatures. Experiments were done to assess the feasibility of this method for cold-trap regeneration. Small-scale simulated cold traps (SCT) were loaded with NaH and NaH plus Na/sub 2/O, and were heated both under vacuum and under a sweep gas at 100 kPa. The evolved hydrogen was converted to water by a CuO bed and collected in a weighing tube.
Date: June 1, 1980
Creator: McPheeters, C.C.; Skladzien, S.B. & Raue, D.J.
Partner: UNT Libraries Government Documents Department

Cesium behavior and control in sodium systems. [LMFBR]

Description: A series of capsule tests were performed to screen candidate packing materials for a Cs trap. Specimens of medium density graphite rho = 1.8 to 1.7 gm/cm/sup 3/ and a low density amorphous carbon foam, Reticulated Vitreous Carbon (RVC) rho = 0.06 gm/cm/sup 3/ were tested. X-ray diffraction verified the hexagonal structure of the graphite specimens and the amorphous structure of the RVC. The test capsules contained approximately 0.1 mCi (3.7 x 10/sup 3/ Kbq)/sup 137/Cs dissolved in 30 gm of sodium. The behavior of Cs in a circulating sodium system was studied in the Fission Product Transport Loop (FPTL). Tracer isotopes, 1 mCi (3.7 x 10/sup 4/KBq)/sup 137/Cs, 1 mCi (3.7 x 10/sup 4/KBq)/sup 134/Cs and 0.5 mCi/sup 22/(1.85 x 10/sup 4/KBq)/sup 22/Na were added to the 19 kg sodium inventory in the loop. The tracer distributions in the loop were monitored with a collimated GeLi detector and multichannel analyzer.
Date: March 1, 1980
Creator: Colburn, R.P. & Maffei, H.P.
Partner: UNT Libraries Government Documents Department

Control of radioactive material transport in sodium-cooled reactors

Description: The Radioactivity Control Technology (RCT) program was established by the Department of Energy to develop and demonstrate methods to control radionuclide transport to ex-core regions of sodium-cooled reactors. This radioactive material is contained within the reactor heat transport system with any release to the environment well below limits established by regulations. However, maintenance, repair, decontamination, and disposal operations potentially expose plant workers to radiation fields arising from radionuclides transported to primary system components. This paper deals with radioactive material generated and transported during steady-state operation, which remains after /sup 24/Na decay. Potential release of radioactivity during postulated accident conditions is not discussed. The control methods for radionuclide transport, with emphasis on new information obtained since the last Environmental Control Symposium, are described. Development of control methods is an achievable goal.
Date: March 17, 1980
Creator: Brehm, W.F.
Partner: UNT Libraries Government Documents Department

Stratospheric H/sub 2/O

Description: Documentation of the extreme aridity (approx. 3% relative humidity) of the lower stratosphere and the rapid decrease of mixing ratio with height just above the polar tropopause (20-fold in the 1st km) was begun by Dobson et al., (1946) in 1943. They recognized that this extreme and persistent aridity must be dynamically maintained else it would have been wiped out by turbulent diffusion. This led Brewer (1949) to hypothesize a stratospheric circulation in which all air enters through the tropical tropopause where it is freeze dried to a mass mixing ratio of 2 to 3 ppM. This dry air then spreads poleward and descends through the polar tropopauses overpowering upward transport of water vapor by diffusion which would otherwise be permitted by the much warmer temperatures of the polar tropopauses. Questions can indeed be raised as to the absolute magnitudes of stratospheric mixing ratios, the effective temperature of the tropical tropopause cold trap, the reality of winter pole freeze-dry sinks and the representativeness of the available observations suggesting an H/sub 2/O mixing ratio maximum just above the tropical tropopause and a constant mixing ratio from the tropopause to 30 to 35 km. However, no model that better fits all of the available data is available, than does the Brewer (1949) hypothesis coupled with a lower stratosphere winter pole, freeze-dry sink, at least over Antarctica. (JGB)
Date: March 25, 1979
Creator: Ellsaesser, H.W.
Partner: UNT Libraries Government Documents Department

FFTF sodium and cover gas characterization and purification

Description: The FFTF Primary and Secondary Heat Transport System (HTS) sodium is purified with cold traps which have packed crystallizers and external economizers. The Primary HTS cold trap is NaK cooled and the Secondary HTS cold traps are air cooled. The FFTF cold traps have maintained high purity in the sodium since sodium fill. Plant operational procedures during fill and initial sodium heatup to 800/sup 0/F were controlled to assure low release rates of impurities to the sodium. The FFTF sodium systems are monitored by plugging temperature indicators and by several sampling methods. During reactor fill and non-fueled operations at 400 to 800/sup 0/F, impurity changes in the sodium were followed by continuous plugging indicator coverage, by exposing wires and foils to measure carbon, hydrogen and oxygen, and by bulk sample analysis of all other trace constituents. The sampling and analysis methods and data are presented, impurity excursions in the cover gas and sodium are described, and impurity trends are discussed.
Date: February 1, 1980
Creator: McCown, J.J.; Bloom, G.R.; Meadows, G.E. & Mettler, G.W.
Partner: UNT Libraries Government Documents Department

Evaporative cooling of highly charged ions in EBIT (Electron Beam Ion Trap): An experimental realization

Description: Both the total number and trapping lifetime of near-neon-like gold ions held in an electron beam ion trap have been greatly increased by a process of 'evaporative cooling'. A continuous flow of low-charge-state ions into the trap cools the high-charge-state ions in the trap. Preliminary experimental results using titanium ions as a coolant are presented. 8 refs., 6 figs., 2 tabs.
Date: December 1, 1988
Creator: Schneider, M.B.; Levine, M.A.; Bennett, C.L.; Henderson, J.R.; Knapp, D.A. & Marrs, R.E.
Partner: UNT Libraries Government Documents Department