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Equilibrium of the System Lanthanum Nitrate-Praseodymium Nitrate-Nitric Acid-Water-Tributyl Phosphate
A study of the extraction characteristics of the three systems lanthanum nitrate--nitric acid--water--tributyl phosphate, praseodymium nitrate--nitric acid--water--tributyl phosphate, and lanthanum nitrate--praseodymium nitrate nitric acid -water--tributyl phosphate was conducted. The separation factors between praseodymium and lanthanum for the system lanthanum nitrate--praseodymium nitrate-nitric acid--water--tributyl phosphate were shown to be a function of the total nitrate concentration of an equilibrium phase and practically independent of solute composition. A method of predicting the concentrations of lanthanum nitrate, praseodymium nitrate, and nitric acid in an equilibrium phase of the system lanthanum nitrate--praseodymium nitrate--nitric acid--water--tributyl phosphate was presented. A comparison of the extraction characteristics of the system rare-earth nitrate--nitric acid--water--tributyl phosphate for the nitrates of lanthanum, praseodymium, neodymium, and samarium was made. (auth)
Date:
November 1, 1960
Creator:
Sharp, B. M. & Smutz, M.
Object Type:
Report
System:
The UNT Digital Library
Strange-quark-matter stars
We investigate the implications of rapid rotation corresponding to the frequency of the new pulsar reported in the supernovae remnant SN1987A. It places very stringent conditions on the equation of state if the star is assumed to be bound by gravity alone. We find that the central energy density of the star must be greater than 13 times that of nuclear density to be stable against the most optimistic estimate of general relativistic instabilities. This is too high for the matter to consist of individual hadrons. We conclude that it is implausible that the newly discovered pulsar, if its half-millisecond signals are attributable to rotation, is a neutron star. We show that it can be a strange quark star, and that the entire family of strange stars can sustain high rotation if strange matter is stable at an energy density exceeding about 5.4 times that of nuclear matter. We discuss the conversion of a neutron star to strange star, the possible existence of a crust of heavy ions held in suspension by centrifugal and electric forces, the cooling and other features. 34 refs., 10 figs., 1 tab.
Date:
November 1, 1989
Creator:
Glendenning, N. K.
Object Type:
Article
System:
The UNT Digital Library
A Process for the Recovery of Uranium From Nuclear Fuel Elements Using Fluid-Bed Drying and Volatility Techniques
A process scheme for the recovery of uranium from fuel elements has been developed. The scheme combines continuous fluid-bed drying and fluoride volatility techniques after initial dissolution of the fuel element in the appropriate aqueous system, hence the designation ADF, Aqueous Dry Fluorination Process. The application of this process to the recovery of uranium from highly enriched, low uranium-zirconium alloy plate-type fuels is described. ln the process, the feed solution is sprayed horizontally through a two-fluid nozzle and is atomized directly in the heated fluidized bed. The spray droplets are dried on the fluidized particles and form a dense coating. Excessive particle growth was limited by the use of air attrition-jets inserted directly in the bed. Aqueous hydrofluoric acid solutions containing l.2 to 3.6 M zirconiuni, 0.007 to 0.03 M uranium, and free acid concentrations from 1 to about l0 M were successfully processed in a 6-in.-diameter Inconel fluid-bed spray dryer. Rates equivalent to about 3.l kg/hr of zirconium were achieved, 160 ml/min with the most concentrated feed solution. Experiments were successfully carried out from 240 to 450 deg C. A new design for a two-fluid nozzle was developed. Extensive work was done to identify the various zirconium fluoride compounds …
Date:
November 1, 1961
Creator:
Levitz, N.; Barghusen, J.; Carls, E. & Jonke, A. A.
Object Type:
Report
System:
The UNT Digital Library
Transport-diffusion comparisons for small core LMFBR disruptive accidents
A number of numerical experiments were performed to assess the validity of diffusion theory for calculating the reactivity state of various small core LMFBR disrupted geometries. The disrupted configurations correspond, in general, to various configurations predicted by SAS3A for transient undercooling (TUC) and transient overpower (TOP) accidents for homogeneous cores and to the ZPPR-7 configurations for heterogeneous core. In all TUC cases diffusion theory was shown to be inadequate for the calculation of reactivity changes during core disassembly.
Date:
November 1, 1977
Creator:
Tomlinson, E.T.
Object Type:
Report
System:
The UNT Digital Library
Simple scaling model for exploding pusher targets
A simple model has been developed which when normalized by experiment or Lasnex calculations can be used to scale neutron yields for variations in laser input power and pulse length and target radius and wall thickness. The model also illucidates some of the physical processes occurring in this regime of laser fusion experiments. Within certain limitations on incident intensity and target geometry, the model scales with experiments and calculations to within a factor of two over six decades in neutron yield.
Date:
November 4, 1977
Creator:
Storm, E. K.; Larsen, J. T.; Nuckolls, J. H.; Ahlstrom, H. G. & Manes, K. R.
Object Type:
Article
System:
The UNT Digital Library
Annotated bibliography: hazard assessments for the geologic isolation of nuclear wastes. Final report. Center for Resource and Environmental Systems Studies report No. 41
This report presents an annotated bibliography of risk assessments that are pertinent to constructing, operating, and decommissioning a federal repository for the underground storage of radioactive waste. This might be considered as a first phase in an assessment of the risks associated with radioactive waste storage. Only those documents judged to be the more pertinent are abstracted. The abstracts are grouped under 13 classifications. A subject and author index is provided.
Date:
November 1, 1977
Creator:
Suta, B.E.; Mara, S.J.; Radding, S.B. & Weisbecker, L.W.
Object Type:
Report
System:
The UNT Digital Library
Arc Melting in the Tungsten Electrode Furnace
An arc furnace is described which employs a nonconsumable tungsten electrode and a water-cooled copper hearth. It is used successfully for melting refractory metals and alloys. The furnace is equipped with a vacuum system, an inert gas supply, and an 800-ampere directcurrent power supply. (auth)
Date:
November 1, 1961
Creator:
Williams, D. E. & Levingston, H. L.
Object Type:
Report
System:
The UNT Digital Library
VOID COEFFICIENT OF REACTIVITY ASSOCIATED WITH THE ISLAND REGION OF THE HFIR
Changes in neutron multiplication caused by voids in the island of the HFlR were calculated and measured experimentally. The results indicated that with only water initially in the island the maximum change in neutron multiplication ( DELTA k/sub max) associated with island voids is 0.032 with a corresponding void fraction of 70%. With a simulated 300 g Pu target in the island DELTA k/sub max/ was 0.0l6, and the corresponding void fraction was 42%. In view of these large changes in neutron multiplication, calculations were made to determine what additional materials could be used in the island to reduce DELTA k/sub max/ and what the associated decrease in peak thermal flux wouId be. The results indicated that of the materials considered the use of beryllium in the water island resulted in the smallest decrease in flux for a specified DELTA k/sub max/. To reduce DELTA k/sub max/ to 0.01 required 26% by volume of beryllium in the island; the corresponding reduction in thermal flux, as compared to an all-water island, was about 10%. In order to reduce DELTA k/sub max/ to 0.0l with a 300 g Pu target in the island, the aIuminum-to-water ratio of the target had to be …
Date:
November 15, 1961
Creator:
Cheverton, R.D.
Object Type:
Report
System:
The UNT Digital Library
Self-consistent model calculations of the ordered S-matrix and the cylinder correction
The multiperipheral ordered bootstrap of Rosenzweig and Veneziano is studied by using dual triple Regge couplings exhibiting the required threshold behavior. In the interval -0.5 less than or equal to t less than or equal to 0.8 GeV/sup 2/ self-consistent reggeon couplings and propagators are obtained for values of Regge slopes and intercepts consistent with the physical values for the leading natural-parity Regge trajectories. Cylinder effects on planar pole positions and couplings are calculated. By use of an unsymmetrical planar ..pi..--rho reggeon loop model, self-consistent solutions are obtained for the unnatural-parity mesons in the interval -0.5 less than or equal to t less than or equal to 0.6 GeV/sup 2/. The effects of other Regge poles being neglected, the model gives a value of the ..pi..--eta splitting consistent with experiment. 24 figures, 1 table, 25 references.
Date:
November 1, 1977
Creator:
Millan, J.
Object Type:
Report
System:
The UNT Digital Library
Two-stage process for conversion of synthesis gas to high quality transportation fuels. Quarterly report, 8 June-30 September 1983
The design of two large hot-flow models, to be used for slurry bubble-column hydrodynamic studies, is described. Scoping experiments were performed in smaller models to study the effects of feed-gas distributor type, column diameter, and liquid medium on gas holdup and bubble sizes. In addition, a literature review of bubble-column hydrodynamics is presented. Modifications to improve the operation and flexibility of the existing two stage pilot plant have been designed and construction initiated. Also, a sample of reactor-wax was fractionated under vacuum in a laboratory still. 8 figures, 4 tables.
Date:
November 1, 1983
Creator:
Kuo, J.C.W.
Object Type:
Report
System:
The UNT Digital Library
Weak interaction effects in e/sup +/e/sup -/ annihilation with polarised beams
Although the standard gauge model of weak and electromagnetic interactions based on the work of Salam and Weinberg has met with great success, there are experimental facts that will require its extension or its modification to a new gauge model; the discovery of a heavy lepton at SLAC and the absence of parity violation in atoms that is expected from the neutral weak current coupling to electrons are discussed. Three tests are proposed that bear on these questions. First, heavy lepton production in e/sup +/e/sup -/ annihilation when one of the incident beams is longitudinally polarized is considered and the purely leptonic decay of this heavy lepton is examined. An asymmetry in the inclusive angular distribution of one charged lepton (electron or muon) is important in determining the structure of weak interactions of the heavy lepton. In fact, this angular asymmetry easily distinguishes between the cases V - A and V + A for the heavy lepton current. Then, the decay channel L ..-->.. ..nu../sub L/ + one hadron is considered (L = heavy lepton) under the same experimental set-up and the inclusive one-hadron angular distribution examined. Parity nonconservation in the decay of the heavy lepton causes a conspicuous forward-backward …
Date:
November 2, 1977
Creator:
Simard, R.
Object Type:
Report
System:
The UNT Digital Library
Ultrafast gated intensifier design for laser fusion x-ray framing applications
A major challenge for laser fusion is the study of the symmetry and the hydrodynamic stability of imploding fuel capsules. Streaked x-radiography, in one space and one time dimension, does not provide sufficient information. Two (spatial) dimensional frames of 10 to 100 ps duration are required with good image quality, minimum geometrical distortion (approximately 1%), dynamic range greater than 1000 and greater than 200 x 200 pixels. A gated transmission line imager (TLI) can meet these requirements with frame times between 30 and 100 ps. An instrument of this type is now being developed. Progress on this instrument including theory of operation, ultrafast pulse generation and propagation, component integration, and high resolution phosphor screen development are presented.
Date:
November 1, 1983
Creator:
Price, R.H.; Wiedwald, J.D.; Kalibjian, R.; Thomas, S.W. & Cook, W.M.
Object Type:
Article
System:
The UNT Digital Library
Proceedings of the US DOE/UK AEA Workshop on Facility Design
This document contains the proceeding of a Workshop on Facility Design that was held between the United States Department of Energy and the United Kingdom Atomic Energy Authority, Albuquerque, New Mexico, October 27--29, 1986. The intention of the workshop was to display relevant design criteria and to demonstrate for various US and UK facilities, current and projected criteria and how these criteria have been satisfied by facility design. Specific examples concern small plants, large plants, and waste stores.
Date:
November 1, 1986
Creator:
unknown
Object Type:
Article
System:
The UNT Digital Library
Distributed energy systems: a review of related technologies
Twenty-three papers were presented at the meeting. A separate abstract was prepared for each paper. (LCL)
Date:
November 1, 1979
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Development of a three-dimensional model of the atmospheric boundary layer using the finite element method
This report summarizes our current effort and ideas toward the development of a model for the planetary boundary layer using the finite element technique. As an initial step, the finite element methodology is applied to simpler version of the boundary layer equations given by the two-dimensional, constant-property, incompressible conservation equations (Navier-Stokes equations). Solution procedures for both the steady-state and transient equations are discussed. For the transient problem, a variable time-step, trapezoid-rule algorithm with dynamic time-truncation error control is presented. The resulting system of nonlinear algebraic equations is solved by a Newton iteration procedure with a frontal solution scheme used for the linear set of equations. The need to develop a suitable linear equation solver, with respect to minimization of computer storage and execution costs, particularly for large (three-dimensional) finite element problems, is also discussed.
Date:
November 22, 1977
Creator:
Lee, R. L. & Gresho, P. M.
Object Type:
Report
System:
The UNT Digital Library
Examination of fast reactor fuels, FBR analytical quality assurance standards and methods, and analytical methods development: Irradiation tests. Progress report, July 1--September 30, 1977. [PuO/sub 2/; UO/sub 2/]
Information is presented concerning the examination of fast reactor fuels, FBR analytical quality assurance standards, and analytical methods development irradiation tests.
Date:
November 1, 1977
Creator:
Baker, R.D. (comp.)
Object Type:
Report
System:
The UNT Digital Library
Hand deburring of precision miniature parts
None
Date:
November 1, 1975
Creator:
Gillespie, LaRoux K.
Object Type:
Report
System:
The UNT Digital Library
Numerical methods for laser fusion
The LASNEX computer code was developed to study the many interrelated physical processes important in the effort to achieve laser initiated fusion. It has been used to calculate the results of numerous laser plasma experiments and to design targets and determine desirable laser pulse characteristics for future experiments. Some processes, such as hydrodynamics, are well formulated in fundamental equations and can be solved with high accuracy by sophisticated numerical methods. Other processes, such as laser absorption and electron transport, are less well understood and do not, in general, warrant the use of highly accurate techniques. Numerical models were chosen that adequately represent each physical process, keeping in mind its inherent uncertainties, the importance of the process to the overall calculation, and its effect on the determination of experimental observables.
Date:
November 3, 1977
Creator:
Zimmerman, G.B.
Object Type:
Article
System:
The UNT Digital Library
Data report of a pretest analysis of soil-structure interaction and structural response in low-amplitude explosive testing (50 KG) of the heissdampfreaktor (HDR)
This report describes a three-dimensional nonlinear TRANAL finite element analysis of a nuclear reactor subjected to ground shaking from a buried 50 kg explosive source. The analysis is a pretest simulation of a test event which was scheduled to be conducted in West Germany on 3 November 1979.
Date:
November 29, 1979
Creator:
Vaughan, D.K.; Sandler, I.; Rubin, D.; Isenberg, J. & Nikooyeh, H.
Object Type:
Report
System:
The UNT Digital Library
Analysis of Radiation Doses from Operation of Postulated Commercial Spent Fuel Transportation Systems
This report contains a system study of estimated radiation doses to the public and workers resulting from the transport of spent fuel from commercial nuclear power reactors to a geologic repository. The report contains a detailed breakdown of activities and a description of time/distance/dose-rate estimates for each activity within the system. Collective doses are estimated for each of the major activities at the reactor site, in transit, and at the repository receiving facility. Annual individual doses to the maximally exposed individuals or groups of individuals are also estimated. A total of 17 alternatives and subalternatives to the postulated reference transportation system are identified, conceptualized, and their dose-reduction potentials and costs estimated. Resulting ratios of ..delta..cost/..delta..collective system dose for each alternative relative to the postulated reference transportation system are given. Most of the alternatives evaluated are estimated to provide both cost and dose reductions. Major reductions in transportation system dose and cost are estimated to result from using higher-capacity rail and truck casks, and particularly when replacing legalweight truck casks with ''advanced design'' overweight truck casks. The greatest annual dose reduction to the highest exposed individual workers (i.e., at the repository) is estimated to be achieved by using remote handling equipment …
Date:
November 1, 1987
Creator:
Schneider, K. J.; Hostick, C. J.; Ross, W. A.; Peterson, R. W.; Smith, R. I.; Stiles, D. L. et al.
Object Type:
Report
System:
The UNT Digital Library
Remote Working Level Monitor. Final report
The Remote Working Level Monitor (RWLM) is an instrument used to remotely monitor the RN-daughter concentrations and the Working Level (WL). It is an ac powered, microprocessor based instrument which multiplexes two independent detector units to a single central processor unit (CPU). The CPU controls the actuation of the detector units and processes and outputs the data received from these remote detector units. The remote detector units are fully automated and require no manual operation once they are set up. They detect and separate the alpha emitters of RaA and RaC' as well as detecting the beta emitters of RaB and RaC. The resultant pulses from these detected radioisotopes are transmitted to the CPU for processing. The programmed microprocessor performs the mathematical manipulations necessary to output accurate Rn-daughter concentrations and the WL. A special subroutine within the program enables the RWLM to run and output a calibration procedure on command. The data resulting from this request can then be processed in a separate program on most computers capable of BASIC programming. The calibration program results in the derivation of coefficients and beta efficiencies which provides calibrated coefficients and beta efficiencies.
Date:
November 18, 1977
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Estimates of post-acceleration longitudinal bunch compression
A simple analytic method is developed, based on physical approximations, for treating transient implosive longitudinal compression of bunches of heavy ions in an accelerator system for ignition of inertial-confinement fusion pellet targets. Parametric dependences of attainable compressions and of beam path lengths and times during compression are indicated for ramped pulsed-gap lines, rf systems in storage and accumulator rings, and composite systems, including sections of free drift. It appears that for high-confidence pellets in a plant producing 1000 MW of electric power the needed pulse lengths cannot be obtained with rings alone unless an unreasonably large number of them are used, independent of choice of rf harmonic number. In contrast, pulsed-gap lines alone can meet this need. The effects of an initial inward compressive drift and of longitudinal emittance are included.
Date:
November 25, 1977
Creator:
Judd, D.L.
Object Type:
Article
System:
The UNT Digital Library
OPTIMUM FILL VOLUMES IN POT CALCINATION OF RADIOACTIVE WASTES
The 15,000 MW nuclear economy assumed for the long range study of pot calcination costs reported earlier was used as a basis for calculating optimum fill volumes. An algebraic expression was developed for cost as a functmon of the normalized radius of the central void space in a partially filled vessel. Minima of this expression were found for acmdmc and neutralized wastes in 6, 12, and 24in.-diameter vessels. Optimum fill volumes decreased as vessel diameter increased, varying for acidic wastes from 99.8% for 6-in.-diameter vessels to 92.5% for 24-in.diameter vessels. Decreases in costs by using optimum fill volumes instead of the 90% fill volume assumed for all cases in the long range study were small, the largest being an 8% decrease for neutralized wastes in 6- in.-diameter vessels. (auth)
Date:
November 17, 1961
Creator:
Perona, J.J.
Object Type:
Report
System:
The UNT Digital Library
Plasma Separation Process: Betacell (BCELL) code: User's manual. [Bipolar barrier junction]
The emergence of clearly defined applications for (small or large) amounts of long-life and reliable power sources has given the design and production of betavoltaic systems a new life. Moreover, because of the availability of the plasma separation program, (PSP) at TRW, it is now possible to separate the most desirable radioisotopes for betacell power generating devices. A computer code, named BCELL, has been developed to model the betavoltaic concept by utilizing the available up-to-date source/cell parameters. In this program, attempts have been made to determine the betacell energy device maximum efficiency, degradation due to the emitting source radiation and source/cell lifetime power reduction processes. Additionally, comparison is made between the Schottky and PN junction devices for betacell battery design purposes. Certain computer code runs have been made to determine the JV distribution function and the upper limit of the betacell generated power for specified energy sources. A Ni beta emitting radioisotope was used for the energy source and certain semiconductors were used for the converter subsystem of the betacell system. Some results for a Promethium source are also given here for comparison. 16 refs.
Date:
November 13, 1987
Creator:
Taherzadeh, M.
Object Type:
Report
System:
The UNT Digital Library