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Modification of Particle Distributions By MHD Instabilities I

Description: The modification of particle distributions by low amplitude magnetohydrodynamic modes is an important topic for magnetically confined plasmas. Low amplitude modes are known to be capable of producing significant modification of injected neutral beam profiles, and the same can be expected in burning plasmas for the alpha particle distributions. Flattening of a distribution due to phase mixing in an island or due to portions of phase space becoming stochastic is a process extremely rapid on the time scale of an experiment but still very long compared to the time scale of guiding center simulations. Thus it is very valuable to be able to locate significant resonances and to predict the final particle distribution produced by a given spectrum of magnetohydrodynamic modes. In this paper we introduce a new method of determining domains of phase space in which good surfaces do not exist and use this method for quickly determining the final state of the particle distribution without carrying out the full time evolution leading to it.
Date: December 23, 2010
Creator: White, R. B.
Partner: UNT Libraries Government Documents Department

The Use of Manganese Substituted Ferrotitanium Alloys for Energy Storage

Description: Experimental results are presented on properties of major practical importance in the utilization of manganese-substituted ferrotitanium alloys as hydrogen storage media. Consideration is given to (1) pressure-composition-temperature characteristics, (2) particle attrition properties, (3) effects of long-term cycling on alloy stability, (4) ease of activation and reactivation, and (5) effects of contaminants on alloy activity. The performance of ternary alloys is compared with that of titanium iron as is the development of an optimum ternary alloy for use with a particular peak shaving operation, i.e., the regenerative H2-Cl system.
Date: December 5, 1977
Creator: Johnson, J.R. & Reilly, J.
Partner: UNT Libraries Government Documents Department

U.S. Nuclear Regulatory Commission Extremely Low Probability of Rupture pilot study : xLPR framework model user's guide.

Description: For the U.S. Nuclear Regulatory Commission (NRC) Extremely Low Probability of Rupture (xLPR) pilot study, Sandia National Laboratories (SNL) was tasked to develop and evaluate a probabilistic framework using a commercial software package for Version 1.0 of the xLPR Code. Version 1.0 of the xLPR code is focused assessing the probability of rupture due to primary water stress corrosion cracking in dissimilar metal welds in pressurizer surge nozzles. Future versions of this framework will expand the capabilities to other cracking mechanisms, and other piping systems for both pressurized water reactors and boiling water reactors. The goal of the pilot study project is to plan the xLPR framework transition from Version 1.0 to Version 2.0; hence the initial Version 1.0 framework and code development will be used to define the requirements for Version 2.0. The software documented in this report has been developed and tested solely for this purpose. This framework and demonstration problem will be used to evaluate the commercial software's capabilities and applicability for use in creating the final version of the xLPR framework. This report details the design, system requirements, and the steps necessary to use the commercial-code based xLPR framework developed by SNL.
Date: December 1, 2010
Creator: Kalinich, Donald A.; Sallaberry, Cedric M. & Mattie, Patrick D.
Partner: UNT Libraries Government Documents Department

Attributes of the Federal Energy Management Program's Federal Site Building Characteristics Database

Description: Typically, the Federal building stock is referred to as a group of about one-half million buildings throughout the United States. Additional information beyond this level is generally limited to distribution of that total by agency and maybe distribution of the total by state. However, additional characterization of the Federal building stock is required as the Federal sector seeks ways to implement efficiency projects to reduce energy and water use intensity as mandated by legislation and Executive Order. Using a Federal facility database that was assembled for use in a geographic information system tool, additional characterization of the Federal building stock is provided including information regarding the geographical distribution of sites, building counts and percentage of total by agency, distribution of sites and building totals by agency, distribution of building count and floor space by Federal building type classification by agency, and rank ordering of sites, buildings, and floor space by state. A case study is provided regarding how the building stock has changed for the Department of Energy from 2000 through 2008.
Date: December 31, 2010
Creator: Loper, Susan A. & Sandusky, William F.
Partner: UNT Libraries Government Documents Department

INVENTION REPORT--DEVELOPMENT OF A SOLUTION TO OXIDIZE AND DISSOLVE URANIUM METAL AND ITS OXIDES

Description: Decontamination of a high-temperature pressurizedwater reactor core- coolant recirculation system following a fuel element cladding failure requires the dissolution of uranium oxides + uranium metal. An oxalic--peroxide-peracetic solution was developed which was found to be superior to other solutions for this task. The solution composition is: oxalic acid, 2.3 g/l: sodium oxalate, 32.0 g/ l; hydrogen peroxide, 15.0 g/l; 8-quinolinol, 1.0 g/l; and 40% peracetic acid, 12.5 g/l. 8-Quinolinol suppresses the decomposition of H/sub 2/O/sub 2/ in steel vessels. Corrosion data indicate that, of all the structural materials tested, only brass and brass alloys are corronded to any extent by this solution. This solution was used in the decontamination of the Plutonium Recycle Test Reactor. (D.L.C.)
Date: December 31, 1962
Creator: Weed, R.D.
Partner: UNT Libraries Government Documents Department

IONIUM (THORIUM-230) FOR RADIOISOTOPE PREPARATION--STATUS REPORT

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

Description of heat flux measurement methods used in hydrocarbon and propellant fuel fires at Sandia.

Description: The purpose of this report is to describe the methods commonly used to measure heat flux in fire applications at Sandia National Laboratories in both hydrocarbon (JP-8 jet fuel, diesel fuel, etc.) and propellant fires. Because these environments are very severe, many commercially available heat flux gauges do not survive the test, so alternative methods had to be developed. Specially built sensors include 'calorimeters' that use a temperature measurement to infer heat flux by use of a model (heat balance on the sensing surface) or by using an inverse heat conduction method. These specialty-built sensors are made rugged so they will survive the environment, so are not optimally designed for ease of use or accuracy. Other methods include radiometers, co-axial thermocouples, directional flame thermometers (DFTs), Sandia 'heat flux gauges', transpiration radiometers, and transverse Seebeck coefficient heat flux gauges. Typical applications are described and pros and cons of each method are listed.
Date: December 1, 2010
Creator: Nakos, James Thomas
Partner: UNT Libraries Government Documents Department

A PRELIMINARY INVESTIGATION OF A CHROMATOGRAPHIC COLUMN SEPARATION OF RARE EARTHS USING Di(2-ETHYLHEXYL)PHOSPHORIC ACID

Description: A new chromatographic separation of small amounts of rare earths was devised and tested with carrier-free radiotracers of Nd/sup 147/, Pm/sup 147/, and Eu/sup 155/. The method uses di(2-ethylhexyl)orthophosphoric acid (HDEHP) as a stationary phase supported on a column of aluminum oxide. and elution is with dilute aqueous hydrochloric acid. Column behavior is similar to solvent extraction using HDEHP where separation factors average 2.5 for adjacent rare earths. (auth)
Date: December 30, 1958
Creator: Winchester, J.W.
Partner: UNT Libraries Government Documents Department

Twining characters and orbit Lie algebras

Description: We associate to outer automorphisms of generalized Kac-Moody algebras generalized character-valued indices, the twining characters. A character formula for twining characters is derived which shows that they coincide with the ordinary characters of some other generalized Kac-Moody algebra, the so-called orbit Lie algebra. Some applications to problems in conformal field theory, algebraic geometry and the theory of sporadic simple groups are sketched.
Date: December 5, 1996
Creator: Fuchs, Jurgen; Ray, Urmie; Schellekens, Bert & Schweigert, Christoph
Partner: UNT Libraries Government Documents Department

Super-High Temperature Alloys and Composites from NbW-Cr Systems

Description: Nickel base superalloys must be replaced if the demand for the materials continues to rise for applications beyond 1000{sup o}C which is the upper limit for such alloys at this time. There are non-metallic materials available for such high temperature applications but they all present processing difficulties because of the lack of ductility. Metallic systems can present a chance to find materials with adequate room temperature ductility. Obviously the system must contain elements with high melting points. Nb has been chosen by many investigators which has a potential of being considered as a candidate if alloyed properly. This research is exploring the Nb-W-Cr system for the possible choice of alloys to be used as a high temperature material.
Date: December 31, 2008
Creator: Varma, Shailendra
Partner: UNT Libraries Government Documents Department

DMM: A MULTIGROUP, MULTIREGION ONE-SPACE-DIMENSIONAL COMPUTER PROGRAM USING NEUTRON DIFFUSION THEORY. PART II. DMM PROGRAM DESCRIPTION

Description: Operating instructions are presented for DMM, a Remington Rand 1103A program using one-space-dimensional multigroup diffusion theory to calculate the reactivity or critical conditions and flux distribution of a multiregion reactor. Complete descriptions of the routines and problem input and output specifications are also included. (D.L.C.)
Date: December 31, 1960
Creator: Kavanagh, D.L.; Antchagno, M.J. & Egawa, E.K.
Partner: UNT Libraries Government Documents Department

Solvent Extraction Recovery and Purification of Strontium-90

Description: A solvent extraction process was developed to produce high-purity Sr/sup 90/ from an irradiated U reprocessing waste solutlon. The extractant is D2EHPA diluted with TBP and Shell Spray Base. The process uses an acetic acid-acetate huffered aqueous phsse which is countercurrently contracted with the D2EHPA organic phase. Calcium and some Ce/sup 144/ extract with the Sr/sup 90/; extraction of other contaminants (Zr/sup 95/, Nb/sup 95/, Ru/sup 106/, and inert lead and iron) is prevented by adding either DTPA or EDTA to the feed solution. Decontamination from Ca and Ce/sup 144/ is provided by back extraction of the Sr/ sup 90/ into an aqueous 1M citric acid solution. The process was used to isolate and purify about one megacurie of Sr/sup 90/ for subsequent use in the fabrication of thermoelectric power generators as part of the Systems for Nuclear Auxiliary Power (SNAP) program. (auth)
Date: December 13, 1961
Creator: Schulz, W. W.; Mendel, J. E. & Richardson, G. L.
Partner: UNT Libraries Government Documents Department

SIGMA PLUG WELDING OF SPUN-OVER FUEL CANS

Description: Efforts made to employ the sigma welding process for plug welding Closures in spun-over fuel cans were unsuccessful. No combination of welding conditions was found which would produce satisfactory, leak-tight, plug welds in aluminum. (auth)
Date: December 1, 1952
Creator: Winsor, F.J.
Partner: UNT Libraries Government Documents Department

RADIOACTIVITY IN SILT OF THE CLINCH AND TENNESSEE RIVERS

Description: Surveys of radioactivity in the Clinch and Tennessee rivers during 1954 through 1958 are summarized. It is concluded that no immediate hazard exists due to the reconcentration of radioactive materials in downstream bottom sediments, However, if the amount of radioactivity in the bottom sediment continues to increase for the next few years, it will be necessary to re-evaluate our present waste disposal policy in order to further restrict the release of ralioactive wastes to the Clinch River. The most probable effect of the radioactive sediment on industry would be an increased background counting rate if sand from the river bottom were used in making concrete for the construction of counting rooms of instrument laboratories. The problem ofthe radioactivity in solution in the river water would have to be considered before using the downstream water as process water in the manufacture of film emulsions or other photographic materials, (auth)
Date: December 1, 1959
Creator: Cottrell, W.D.
Partner: UNT Libraries Government Documents Department

High Temperature Battery for Drilling Applications

Description: In this project rechargeable cells based on the high temperature electrochemical system Na/beta''-alumina/S(IV) in AlCl3/NaCl were developed for application as an autonomous power source in oil/gas deep drilling wells. The cells operate in the temperature range from 150 C to 250 C. A prototype DD size cell was designed and built based on the results of finite element analysis and vibration testing. The cell consisted of stainless steel case serving as anode compartment with cathode compartment installed in it and a seal closing the cell. Critical element in cell design and fabrication was hermetically sealing the cell. The seal had to be leak tight, thermally and vibration stable and compatible with electrode materials. Cathode compartment was built of beta''-alumina tube which served as an electrolyte, separator and cathode compartment.
Date: December 31, 2009
Creator: Caja, Josip
Partner: UNT Libraries Government Documents Department