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Disposal of type-II long-lived fission products into outer space

Description: The authors propose an alternative approach to dispose of long-lived fission products (LLFPs) of type-II, such as {sup 79}Se, {sup 99}Tc, {sup 107}Pd, {sup 126}Sn, {sup 129}I, {sup 135}Cs, and long-lived radioactive {sup 93}Zr into outer solar space. An escape velocity from the solar system of 42 km/s will be provided from either a parking orbit or the moon`s surface using an electrostatic accelerator and by neutralizing the charged accelerated LLFPs ions. LLFP ions must be neutralized to avoid their being trapped in earth and solar magnetic fields; almost 100% neutralization can be achieved by recirculating the non-neutralized ions through a magnetic field in the neutralizing device. This mode of disposition requires 2.2 kW power to eject most of the LLFPs generated by one LWR. This process is much smaller than a medium-energy proton beam power, a few tens of MW, which would be necessary to transmute these LLFPs using spallation neutrons created by protons. Due to their low radioactivity composed of mainly beta decay and low-energy gamma-rays, the shielding needed is not excessive and can be easily accommodated.
Date: December 31, 1996
Creator: Takahashi, Hiroshi & Chen, Xinyi
Partner: UNT Libraries Government Documents Department

RADIOACTIVE CHEMICAL ELEMENTS IN THE ATOMIC TABLE.

Description: In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (longest-lived) known isotope as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular elements has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass number to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of ''these constants'' for use in chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was most stable, i.e., it had the longest known half-life. In their 1973 report, the Commission noted that the users of the Atomic Weights Table were dissatisfied with the omission of values in the Table for some elements and it was decided to reintroduce the mass ...
Date: August 13, 2005
Creator: HOLDEN, N. E.
Partner: UNT Libraries Government Documents Department

Prospects for baryon instability search with long-lived isotopes

Description: In this paper we consider the possibility of observation of baryon instability processes occurring inside nuclei by searching for the remnants of such processes that could have been accumulated in nature as mm long-lived isotopes. As an example, we discuss here the possible detection of traces of {sup 97}Tc, {sup 98}Tc, and {sup 99}Tc in deep-mined nonradioactive tin ores.
Date: December 31, 1996
Creator: Efremenko, Yu.; Bugg, W.; Cohn, H.; Kamyshkov, Yu.; Parker, G. & Plasil, F.
Partner: UNT Libraries Government Documents Department

Enhancements to transmutation system performance through use of an accelerator/fluid fuel combination

Description: The destruction of plutonium and other long-lived radionuclides in high-level nuclear waste is receiving considerable international technical interest and effort. At Los Alamos, accelerator-based concepts are under investigation which achieve high burnups of plutonium and other actinides and which simultaneously transmute key long-lived fission products. This paper describes quantitative enhancements brought through use of an accelerator-driven/fluid fuel subcritical blanket. Results are described covering robust response to reactivity insertions, increased neutron economy for transmutation of long-lived fission products using thermal neutrons, and reduced frequencies required for fuel cleanup.
Date: July 1995
Creator: Arthur, E. D.; Buksa, J.; Davidson, J. W. & Poston, D.
Partner: UNT Libraries Government Documents Department

Accelerator transmutation of nuclear waste: Towards the elimination of long-lived radioactive waste

Description: Researchers at Los Alamos have been developing transmutation concepts involving accelerator-driven nuclear systems. A medium energy, high current proton beam strikes a heavy metal target, producing a high flux of spallation neutrons. These neutrons are moderated to near-thermal energies in a blanket surrounding the target. Materials to be transmuted flow through the blanket region where they are fissioned or transmuted to stable nuclides. Stable or short-lived nuclides are separated while the long-lived radioactive species are returned to the blanket. For most applications the fission energy produced is much greater than that required to power the accelerator and can be directed to the commercial power grid. A number of possible applications are envisioned for accelerator-driven nuclear systems. These include destruction of surplus weapons-grade plutonium, production of tritium, transmutation of commercial spent fuel, and even commercial power generation in next-generation nuclear power plants. Some of these applications will be discussed with particular emphasis on the required chemical separations for such systems.
Date: September 29, 1993
Creator: Dewey, H. J.
Partner: UNT Libraries Government Documents Department

A repository released-dose model for the evaluation of long-lived fission product transmutation effectiveness

Description: A methodology has been developed to quantify the total integrated dose due to a radionuclide species i emplaced in a geologic repository; the focus is on the seven long-lived fission products (LLFPs). The methodology assumes continuous exposure water contaminated with species i at the accessible environment (i.e., just beyond the geologic barrier afforded by the geologic repository). The dose integration is performed out to a reference post-release time. The integrated dose is a function of the total initial inventory of radionuclide i the repository, the time at which complete and instantaneous failure of the engineered barrier (e.g., waste canister) in, a geologic repository occurs, the fractional dissolution rate (from waste solid form) of radionuclide i in ground water, the ground water travel time to the accessible environment, the retardation factor (sorption on the geologic media) for radionuclide i, the time after radionuclide begins to enter the biosphere. In order to assess relative dose, the ratio of total integrated dose to that for a reference LLFP species j (e.g., {sup 99}Tc) was defined. This ratio is a measure of the relative benefit of transmutation of other LLFPs compared to {sup 99}Tc. This methodology was further developed in order to quantify the integrated dose reduction per neutron utilized for LLFP transmutation in accelerator-driven transmutation technologies (ADTT). This measure of effectiveness is a function of the integrated dose due to LLFP species i, the number of total captures in LLFP species i chain per LLFP nuclide fed to the chain at equilibrium, and the number of total captures in related transmutation product (TP) chains per capture in the LLFP species i chain. To assess relative transmutation effectiveness, the ratio of integrated dose reduction per neutron utilization to that for a reference LLFP species j (e.g., {sup 99}Tc) was defined. This relative measure of ...
Date: July 1, 1995
Creator: Davidson, J.W.
Partner: UNT Libraries Government Documents Department

Shipping container for tritiated water

Description: A reusable shipping container for Type B and large quantities of tritiated water has been designed and tested at Mound Facility. An inner and an outer container are used for shipping up to 100,000 Ci of tritium in water absorbed on molecular sieve, silica gel or commercial clay absorbent. The package is commonly called configuration-5 of the model AL-M1 shipping containers. It is the newest member of the AL-M1 family which currently also includes configurations 1 and 3. These other configurations are both for plutonium-239 and uranium-235. The common feature uniting the AL-M1 family is the 55-gal outer drum assembly which is the same for all configurations. The inner containers are quite dissimilar. A ''Safety Analysis Report for Packaging'' or SARP was prepared to qualify the new shipping container for DOT/DOE approval. That document is a formal safety analysis of all three AL-M1 insulated drum shipping container configurations. Together these are officially identified as USA/9507/BLF (ERDA-AL). The Certificate of Compliance has been issued and the SARP has been submitted to NRC for review. A description of the configuration-5 inner container is presented. In addition to the prototype used in testing, thirteen of these containers have been fabricated. One is retained at Mound Facility and twelve will be used at Sandia Laboratories, Livermore, to collect tritiated wastewater. This wastewater will be shipped to Mound for recovery or dispoal of the tritium.
Date: January 1, 1978
Creator: Watkins, R.A.; Rhinehammer, T.B. & Griffin, J.F.
Partner: UNT Libraries Government Documents Department

Interpretation of subcriticality measurements with strong spatial effects

Description: A methodology has been developed to account for spatial effects in subcriticality measurements. Using experimental data, this new analysis methodology allows estimation of model contamination without previous knowledge about the system, neither in the form of neutronic or geometric factor calculations. 5 refs., 1 fig.
Date: January 1, 1987
Creator: March-Leuba, C.; March-Leuba, J. & Difilippo, F.C.
Partner: UNT Libraries Government Documents Department

Status of /sup 241/Am recovery and purification at Los Alamos Scientific Laboratory

Description: Americium recovery was initiated at Los Alamos Scientific Laboratory (LASL) in the late 1940's. The early procedures separated gram quantities of americium from large amounts of impurities including plutonium and the rare earths. Ion exchange procedures were developed for further purification. Until recently, no routine processing of americium has been done at LASL for several years. The increasing demand for americium in oil-well logging instruments and other uses led LASL to develop and install a process to recover larger quantities of americium. The LASL process was developed around the chemistry of americium that had been elucidated both at LASL and at other facilities. Presently, the americium feed is obtained as a by-product from a plutonium purification process at the new plutonium facility at LASL. This feed filtrate from a peroxide precipitation process is precipitated as a slurry of hydroxides, filtered, dissolved in nitric acid, and passed through an anion exchange column to remove any residual plutonium. The americium, contained in the effluent, is precipitated as the oxalate and calcined to the oxide. Americium is also available in other highly salted acidic process streams. These should lend themselves to solvent extraction. Developmental work has been promising, and a dibutyl butyl phosphate-kerosene extraction process is being brought on-line.
Date: January 1, 1980
Creator: Ramsey, H.D.; Clifton, D.G.; Hayter, S.W.; Penneman, R.A. & Christensen, E.L.
Partner: UNT Libraries Government Documents Department

Operating and maintenance experience in tritium environments

Description: This presentation is a summary of practical experience gained over more than twenty years from analyzing failures of process equipment operated in tritium and deuterium environments. Significant improvements have been achieved in design and procurement of new equipment, testing and selection of materials, and gradually more favorable maintenance experience. Preferred materials and inspection methods are described. 6 tabs.
Date: January 1, 1987
Creator: Tuer, G.L.
Partner: UNT Libraries Government Documents Department

Laboratory-scale shielded cell for /sup 252/Cf

Description: A shielded-cell facility for storing and handling remotely up to 2 milligram quantities of unencapsulated /sup 252/Cf has been built in a radiochemistry laboratory at the Test Reactor Area of the Idaho National Engineering Laboratory. Unique features of this facility are its compact bulk radiation shield of borated gypsum and transfer lines which permit the transport of fission product activity from /sup 252/Cf fission sources within the cell to a mass separator and to a fast radiochemistry system in nearby rooms.
Date: January 1, 1979
Creator: Anderl, R.A. & Cargo, C.H.
Partner: UNT Libraries Government Documents Department

Equipment and techniques for remote fabrication and calibration of physically small, high intensity /sup 252/Cf neutron sources

Description: Special equipment and techniques were required to fabricate /sup 252/Cf neutron source capsules, in which milligram quantities of /sup 252/Cf were concentrated in each capsule to approximate an idealized ''point source'' as closely as possible. Through this cooperative effort with the National Bureau of Standards all /sup 252/Cf neutron against the national reference radium-beryllium source.
Date: January 1, 1976
Creator: Williams, L. C.; Bigelow, J. E. & Knauer, J. B. Jr.
Partner: UNT Libraries Government Documents Department

Tritium operating safety seminar, Los Alamos, New Mexico, July 30, 1975

Description: A seminar for the exchange of information on tritium operating and safety problems was held at the Los Alamos Scientific Laboratory. The topics discussed are: (1) material use (tubing, lubricants, valves, seals, etc.); (2) hardware selection (valves, fittings, pumps, etc.); (3) biological effects; (4) high pressure; (5) operating procedures (high pressure tritium experiment at LLL); (6) incidents; and (7) emergency planning. (TFD)
Date: March 1, 1976
Partner: UNT Libraries Government Documents Department

Analysis of the NAEG model of transuranic radionuclide transport and dose

Description: We analyze the model for estimating the dose from /sup 239/Pu developed for the Nevada Applied Ecology Group (NAEG) by using sensitivity analysis and uncertainty analysis. Sensitivity analysis results suggest that the air pathway is the critical pathway for the organs receiving the highest dose. Soil concentration and the factors controlling air concentration are the most important parameters. The only organ whose dose is sensitive to parameters in the ingestion pathway is the GI tract. The air pathway accounts for 100% of the dose to lung, upper respiratory tract, and thoracic lymph nodes; and 95% of its dose via ingestion. Leafy vegetable ingestion accounts for 70% of the dose from the ingestion pathway regardless of organ, peeled vegetables 20%; accidental soil ingestion 5%; ingestion of beef liver 4%; beef muscle 1%. Only a handful of model parameters control the dose for any one organ. The number of important parameters is usually less than 10. Uncertainty analysis indicates that choosing a uniform distribution for the input parameters produces a lognormal distribution of the dose. The ratio of the square root of the variance to the mean is three times greater for the doses than it is for the individual parameters. As found by the sensitivity analysis, the uncertainty analysis suggests that only a few parameters control the dose for each organ. All organs have similar distributions and variance to mean ratios except for the lymph modes. 16 references, 9 figures, 13 tables.
Date: November 1, 1984
Creator: Kercher, J.R. & Anspaugh, L.R.
Partner: UNT Libraries Government Documents Department

Development of tritium technology for the United States magnetic fusion energy program

Description: Tritium technology development for the DOE fusion program is taking place principally at three laboratories, Mound Facility, Argonne National Laboratory and the Los Alamos Scientific Laboratory. This paper will review the major aspects of each of the three programs and look at aspects of the tritium technology being developed at other laboratories within the United States. Facilities and experiments to be discussed include the Tritium Effluent Control Laboratory and the Tritium Storage and Delivery System for the Tokamak Fusion Test Reactor at Mound Facility; the Lithium Processing Test Loop and the solid breeder blanket studies at Argonne; and the Tritium Systems Test Assembly at Los Alamos.
Date: January 1, 1980
Creator: Anderson, J.L. & Wilkes, W.R.
Partner: UNT Libraries Government Documents Department

Energy related studies utilizing K-feldspar thermochronology

Description: Two distinct sources of information are available from a [sup 40]Ar/[sup 39]Ar step-heating experiment: the age spectrum and Arrhenius plot. Model ages are calculated from the flux of radiogenic argon ([sup 40]Ar*) (assuming trapped argon of atmospheric composition) relative to the reactor produced [sup 39]Ar evolved during discrete laboratory heating steps. With the additional assumption that the [sup 39]Ar is uniformly distributed within the sample, we can infer the spatial distribution of the daughter product. ne associated Arrhenius plot, derived by plotting the diffusion coefficient (obtained from the inversion of the 39[sup Ar] release function assuming a single domain) against the inverse temperature of laboratory heating, are a convolution of the parameters which characterize the individual diffusion domains (whether these be dictated by varying length scale, energetics, etc.). However, many and perhaps Most [sup 40]Ar/[sup 39]Ar age spectra for slowly cooled alkali feldspars are significantly different from model age spectra calculated assuming a single diffusion-domain size. In addition, Arrhenius plots calculated from the measured loss of [sup 39]Ar during the step heating experiment show departures from linearity that are inconsistent with diffusion from domains of equal size. By extending the single diffusion-domain closure model (Dodsontype) to apply to minerals with a discrete distribution of domain sizes, we obtained an internally consistent explanation for the commonly observed features of alkali feldspar age spectra and their associated Arrhenius plots.
Date: January 1, 1993
Partner: UNT Libraries Government Documents Department

Reference design for the standard mirror hybrid reactor

Description: This report describes the results of a two-year study by Lawrence Livermore Laboratory and General Atomic Co. to develop a conceptual design for the standard (minimum-B) mirror hybrid reactor. The reactor parameters have been chosen to minimize the cost of producing nuclear fuel (/sup 239/Pu) for consumption in fission power reactors (light water reactors). The deuterium-tritium plasma produces approximately 400 MW of fusion power with a plasma Q of 0.64. The fast-fission blanket, which is fueled with depleted uranium and lithium, generates sufficient tritium to run the reactor, has a blanket energy multiplication of M = 10.4, and has a net fissile breeding ratio of Pu/n = 1.51. The reactor has a net electrical output of 600 MWe, a fissile production of 2000 kg of plutonium per year (at a capacity factor of 0.74), and a net plant efficiency of 0.18. The plasma-containment field is generated by a Yin-Yang magnet using NbTi superconductor, and the neutral beam system uses positive-ion acceleration with beam direct conversion. The spherical blanket is based on gas-cooled fast reactor technology. The fusion components, blanket, and primary heat-transfer loop components are all contained within a prestressed-concrete reactor vessel, which provides magnet restraint and supports the primary heat-transfer loop and the blanket.
Date: May 22, 1978
Creator: Bender, D.J.; Fink, J.H.; Galloway, T.R.; Kastenberg, W.E.; Lee, J.D.; Devoto, R.S. et al.
Partner: UNT Libraries Government Documents Department

Debris collection from implosion of microballoons

Description: Recovery of krypton from implosion of glass microballoons has been studied in the development of a radiochemical diagnostic for determination of <rho r> /sub fuel/. Collection onto metal surfaces following implosions performed on the OMEGA laser with 1-3 TW (1-2 kJ) of 0.35 ..mu..m light is consistent with an ion implantation mechanism. The dependence of the intrinsic collection efficiency on the energy fluence to the collector surface and its variation in implosions carried out under the same nominal conditions indicate ion energies extending to at least 0.1 MeV and energy distribution functions that are sensitive to the details of the implosion dynamics. Intrinsic sticking efficiencies approaching 0.5 can be obtained in the limit of low total energy fluence to the collector surface (less than or equal to 0.1 J cm/sup -2/).
Date: March 28, 1986
Creator: Prussin, S.G.; Lane, S.M.; Richardson, M.C. & Noyes, S.G.
Partner: UNT Libraries Government Documents Department

Design of deuterium and tritium pellet injector systems for Tokamak Fusion Test Reactor

Description: Three pellet injector designs developed by the Oak Ridge National Laboratory (ORNL) are planned for the Tokamak Fusion Test Reactor (TFTR) to reach the goal of a tritium pellet injector by 1988. These are the Repeating Pneumatic Injector (RPI), the Deuterium Pellet Injector (DPI) and the Tritium Pellet Injector (TPI). Each of the pellet injector designs have similar performance characteristics in that they deliver up to 4-mm-dia pellets at velocities up to 1500 m/s with a dsign goal to 2000 m/s. Similar techniques are utilized to freeze and extrude the pellet material. The injector systems incorporate three gun concepts which differ in the number of gun barrels and the method of forming and chambering the pellets. The RPI, a single barrel repeating design, has been operational on TFTR since April 1985. Fabrication and assembly are essentially complete for DPI, and TPI is presently on hold after completing about 80% of the design. The TFTR pellet injector program is described, and each of the injector systems is described briefly. Design details are discussed in other papers at this symposium.
Date: January 1, 1985
Creator: Wysor, R.B.; Baylor, L.R.; Bryan, W.E.; Combs, S.K.; Fisher, P.W.; Lunsford, R.V. et al.
Partner: UNT Libraries Government Documents Department

Edge dynamics in pellet-fuelled inner-wall jet discharges

Description: This paper reports on the density behavior in JET during pellet-fuelled inner-wall discharges without auxiliary heating. Certain discharges, characterized by minor disruptions at the q = 2 surface, show a ten times more rapid decay of the plasma density than previously observed. It is shown that this is related to the combined effects of plasma and wall properties.
Date: January 1, 1987
Creator: Cohen, S.A.; Ehrenberg, J.; Bartlett, D.V.; Campbell, D.J.; Cheetham, A.D.; de Kock, L. et al.
Partner: UNT Libraries Government Documents Department

Artificial heart development program. Volume II. System support. Phase III summary report, July 1, 1973--September 30, 1977

Description: Volume 2 covers major activities of the Artificial Heart Development program that supported the design, fabrication, and test of the system demonstration units. Section A.1.0 provides a listing beyond that of the body of the report on the components needed for an implantation. It also presents glove box sterilization calibration results and results of an extensive mock circulation calibration. Section A.2.0 provides detailed procedures for assembly, preparing for use, and the use of the system and major components. Section A.3.0 covers the component research and development activities undertaken to improve components of the existing system units and to prepare for a future prototype system. Section A.4.0 provides a listing of the top assembly drawings of the major systems variations fabricated and tested.
Date: January 1, 1977
Partner: UNT Libraries Government Documents Department