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Modeling of a dissolution system for transuranic compounds

Description: A system is currently being developed at Lawrence Livermore Laboratory to treat transuranic wastes by means of a mediated electrochemical oxidation process. The process involves generating Ag({sup ++}) from a solution of silver nitrate and nitric acid in an electrochemical cell. Ag({sup ++}) is highly reactive and is capable of attacking many organic and inorganic substances. In particular, if a mixture of particles containing transuranic and other scrap metal oxides is allowed to react with Ag… more
Date: February 1, 1991
Creator: Chiba, Z. & Dease, C.
Partner: UNT Libraries Government Documents Department
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Performance of fast reactor mixed-oxide fuels pins during extended overpower transients

Description: The Operational Reliability Testing (ORT) program, a collaborative effort between the US Department of Energy and the Power Reactor and Nuclear Fuel Development Corp. (PNC) of Japan, was initiated in 1982 to investigate the behavior of mixed-oxide fuel pin under various slow-ramp transient and duty-cycle conditions. In the first phase of the program, a series of four extended overpower transient tests, with severity sufficient to challenge the pin cladding integrity, was conducted. The objectiv… more
Date: February 1, 1991
Creator: Tsai, H.; Neimark, L.A. (Argonne National Lab., IL (USA)); Asaga, T. & Shikakura, S. (Power Reactor and Nuclear Fuel Development Corp., Tokyo (Japan))
Partner: UNT Libraries Government Documents Department
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The industrial consortium for the utilization of the geopressured-geothermal resource

Description: Four feasibility studies have been developed by the INEL on thermal enhanced oil recovery (TEOR) Use of Supercritical Fluid processes for Detoxification of Pollutants, and Hydraulic Conversion to Electricity, and Direct Use. The studies provide information bases for potential industrial partners in the resource utilization. A joint proposal from Los Alamos National Laboratory (LANL) and INEL on supercritical fluid processes in going forward. Western Resources Technology has begun development of… more
Date: February 15, 1991
Creator: Negus-de Wys, J.
Partner: UNT Libraries Government Documents Department
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Evaluation of aging of cast stainless steel components

Description: Cast stainless steel is used extensively in nuclear reactors for primary-pressure-boundary components such as primary coolant pipes, elbows, valves, pumps, and safe ends. These components are, however, susceptible to thermal aging embrittlement in light water reactors because of the segregation of Cr atoms from Fe and Ni by spinodal decomposition in ferrite and the precipitation of Cr-rich carbides on ferrite/austenite boundaries. A recent advance in understanding the aging kinetics is presente… more
Date: February 1, 1991
Creator: Chung, H.M.
Partner: UNT Libraries Government Documents Department
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Standing-Wave Free-Electron Laser Two-Beam Accelerator

Description: A free-electron laser (FEL) two-beam accelerator (TBA) is proposed, in which the FEL interaction takes place in a series of drive cavities, rather than in a waveguide. Each drive cavity is 'beat-coupled' to a section of the accelerating structure. This standing-wave TBA is investigated theoretically and numerically, with analyses included of microwave extraction, growth of the FEL signal through saturation, equilibrium longitudinal beam dynamics following saturation, and sensitivity of the micr… more
Date: February 1, 1991
Creator: Sessler, Andrew M.; Whittum, D. H.; Wurtele, Jonathan S.; Sharp, W. M. & Makowski, M. A.
Partner: UNT Libraries Government Documents Department
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Component and system tests of the SLD Cerenkov Ring Imaging Detector

Description: The components of the SLD barrel Cerenkov Ring Imaging Detector (CRID) are now built and are being installed. We report on tests of these, including tests of the fiber optic calibration system, detailed studies of electron drift paths on production drift boxes and detectors, tests of the dynamic gating system and its effect on drift path distortions due to space-charge, and a measurement of the electron lifetime in a production drift box. In addition, we report on the UV transmission of recircu… more
Date: February 1, 1991
Creator: Antilogus, P.; Aston, D.; Bienz, T.; Bird, F.; Dasu, S.; Dolinsky, S. et al.
Partner: UNT Libraries Government Documents Department
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Conditioning of high gradient H sup - accelerating cavities

Description: Three prototype cavities for the side-coupled accelerating structure of Fermilab's Linac Upgrade have been powered. The cavities operate at a nominal maximum surface electric field of 37--42 MV/m and have been run at close to 60 MV/m at 805 MHz. This paper will present the experience accumulated on x-ray production and RF breakdown frequency. We will try to compare our data with others' experiences with high surface electric fields. 5 refs., 3 figs.
Date: February 1, 1991
Creator: Kroc, T. & Moretti, A.
Partner: UNT Libraries Government Documents Department
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The t-J model at small t/j: Numerical, perturbative, and supersymmetric results

Description: We discuss some recent results for one- and two-hole states in the t-J model at small t/J. These include numerical results (bandwidth determinations and accurate t/J values for 4 {times} 4 lattice one-hole ground-state level crossings), hopping-parameter perturbation theory (which gives the small-t/J one-hole bandwidth in terms of the static-vacancy ground state), and results at the supersymmetric point t/J = 1/2 (exact results for energies and bandwidths.) The perturbative results leads us to … more
Date: February 1, 1991
Creator: Barnes, T.
Partner: UNT Libraries Government Documents Department
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Indirect detection of heavy supersymmetric dark matter

Description: If neutralinos reside in the galactic halo they will be captured in the Sun and annihilate therein producing high-energy neutrinos. Present limits on the flux of such neutrinos from underground detectors such as IMB and Kamiokande 2 may be used to rule out certain supersymmetric dark-matter candidates, while in many other supersymmetric models the rates are large enough that if neutralinos do reside in the galactic halo, observation of a neutrino signal may be possible in the near future. 10 re… more
Date: February 1, 1991
Creator: Kamionkowski, M. (Chicago Univ., IL (USA))/(Fermi National Accelerator Lab., Batavia, IL (USA))
Partner: UNT Libraries Government Documents Department
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Preliminary field demonstration of a fiber-optic TCE sensor. [Trichloroethylene (TCE)]

Description: We have developed a differential-absorption fiber-optic sensor for use in groundwater and vadose zone monitoring of certain volatile organochlorines. The principle of detection is a quantitative, irreversible chemical reaction that forms visible light-absorbing products. The sensor has been evaluated against gas chromatographic (GC) standard measurements and has demonstrated accuracy and sensitivity sufficient for the environmental monitoring of trace levels of trichloroethylene (TCE) and chlor… more
Date: February 1, 1991
Creator: Angel, S.M.; Langry, K.; Roe, J.; Colston, B.W. Jr.; Daley, P.F. & Milanovich, F.P.
Partner: UNT Libraries Government Documents Department
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New acceleration schemes and technologies

Description: The search for new acceleration schemes and technologies has in general, been restricted to a search for higher gradient acceleration, and it has been motivated by the aim of reducing the length, and presumably the cost, of new high energy facilities. In particular, it has been argued that very high energy linear colliders will only be practical if much higher acceleration gradients are employed. This report investigates possible higher acceleration gradient and beam luminosity problems.
Date: February 1, 1991
Creator: Palmer, Robert B.
Partner: UNT Libraries Government Documents Department
open access

Ultrahigh-energy particles from cosmic strings

Description: The idea of production of ultrahigh-energy particles in the present universe due to annihilation or collapse of topological defects is discussed. Topological defects, formed in symmetry-breaking phase transitions in the early universe, can survive till today owing to their topological stability. However, under certain circumstances, topological defects may be physically destroyed. When topological defects are destroyed, the energy contained in the defects can be released in the form of massive … more
Date: February 1, 1991
Creator: Bhattacharjee, P. (Chicago Univ., IL (USA). Astronomy and Astrophysics Center Fermi National Accelerator Lab., Batavia, IL (USA))
Partner: UNT Libraries Government Documents Department
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Can non-Gaussian fluctuations for structure formation arise from inflation

Description: Non-Guassian fluctuation for structure formation may be generated during the inflationary epoch from the nonlinear interaction of two scalar fields with gravity. Semi-analytical calculations are given describing nonlinear long wavelength evolution in 3 + 1 dimensions. Long wavelength fields are governed by a single equation, the separated Hamilton-Jacobi equation (SHJE). I discuss complete analytic solutions of the SHJE for two scalar fields with a potential whose logarithm 1n V ({phi}{sub j}) … more
Date: February 1, 1991
Creator: Salopek, D.S.
Partner: UNT Libraries Government Documents Department
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Weak interactions and presupernova evolution

Description: The role of weak interactions, particularly electron capture and {beta}{sup {minus}} decay, in presupernova evolution is discussed. The present uncertainty in these rates is examined and the possibility of improving the situation is addressed. 12 refs., 4 figs.
Date: February 19, 1991
Creator: Aufderheide, M.B. (Lawrence Livermore National Lab., CA (USA) State Univ. of New York (USA). Dept. of Physics)
Partner: UNT Libraries Government Documents Department
open access

Review of negative hydrogen ion sources

Description: In the early seventies, significant discoveries for H{sup {minus}} ion sources were made at Novosibirsk. These and many improvements which followed have led to useful accelerator sources. With these sources charge-exchange injection into circular accelerators has become desirable and routine. This paper reviews the major developments leading to practical H{sup {minus}} sources. Different types and variations of these sources with some basic physics and operation will be described. The operating… more
Date: February 1, 1991
Creator: Schmidt, C.W.
Partner: UNT Libraries Government Documents Department
open access

Natural inflation

Description: A pseduo-Nambu-Goldstone boson, with a potential of the form V({phi}) = {Lambda}{sup 4}(1 {plus minus} cos({phi}/f)), can naturally give rise to an epoch of inflation in the early universe. Successful inflation can be achieved if f {approximately} m{sub pl} and {Lambda} {approximately} m{sub GUT}. Such mass scales arise in particle physics models with a gauge group that becomes strongly interacting a the GUT scale, e.g., as is expected to happen in the hidden sector of superstring theories. The… more
Date: February 1, 1991
Creator: Frieman, J.A.
Partner: UNT Libraries Government Documents Department
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Mixed field peronnel dosimetry: Part 1, High temperature peak characteristics of the reader-annealed TLD-600

Description: The high temperature peaks (TL peaks 6--7) of TLD-600 are known to have higher responses to high LET radiation than to low LET radiation. These high temperature peak characteristics were studied for the automatic reader-annealed Harshaw albedo neutron TLD. The high temperature peaks response is linear for neutrons over the dose equivalent range tested (0.05--3 mSv of a {sup 252}Cf source moderated by a 15 cm radius polyethylene sphere), but is supralinear above 20 mSv of {sup 137}Cs photons. Th… more
Date: February 1, 1991
Creator: Liu, J.C. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)) & Sims, C.S. (Oak Ridge National Lab., TN (USA))
Partner: UNT Libraries Government Documents Department
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Neutron dose equivalents at the Advanced Light Source: Calculation using the MORSE code vs estimated values

Description: The Advanced Light Source (ALS) complex at the Lawrence Berkeley Laboratory (LBL) is surrounded by a mezzanine and auxiliary buildings. An important radiological problem is the neutron dose equivalent in nearby occupied areas and at the LBL site boundary. Both the direct and air-scattered (skyshine) components of the neutron dose equivalents are evaluated using the neutron transport code MORSE. The shielding was designed using an empirical method based on data scaled from a 1977 SLAC experiment… more
Date: February 1, 1991
Creator: Sun, Rai-Ko S.
Partner: UNT Libraries Government Documents Department
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The status of fuel cell technology

Description: This brief status report provides an introduction to what fuel cells are, why they are important, what uses have been made of them to date, the goals and timetables of current programs, and who the players are in this vital technology. Copies of most of the slides presented and additional diagrams are appended to this paper. Further details can be obtained from the comprehensive texts cited in the bibliography. 11 refs., 44 figs.
Date: February 20, 1991
Creator: O'Sullivan, J.B.
Partner: UNT Libraries Government Documents Department
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DSP: A detailed spectroscopy postprocessor for H-, He-, and Li-like ions

Description: A detailed plasma spectroscopy postprocessor for H-, He-, and Li-like ions with 6 {le} Z {le} 26 has been constructed. The structure of the code and the physics contained within it will be described and a sample application given. 15 refs., 5 figs.
Date: February 22, 1991
Creator: Keane, C.J.; Lee, R.S. (Lawrence Livermore National Lab., CA (USA)) & Grandy, J.P. (Massachusetts Inst. of Tech., Cambridge, MA (USA))
Partner: UNT Libraries Government Documents Department
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Upgrading the Fermilab Linac local control system

Description: A new control system for the Fermilab Linac is being designed, built and implemented. First, the nine-year-old linac control system is being replaced. Second, a control system for the new 805 MHz part of the linac is being built. The two systems are essentially identical, so that when the installations are complete, we will still have a single Linac Control System. 8 refs., 5 figs.
Date: February 1, 1991
Creator: McCrory, E. S.; Goodwin, R. W. & Shea, M. F.
Partner: UNT Libraries Government Documents Department
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Modeling the Longitudinal Wall Impedance Instability in Heavy Ion Beams Using an R-Z PIC Code

Description: The effects of the longitudinal wall impedance instability in a heavy ion beam are of great interest for heavy ion fusion drivers. We are studying this instability using the R-Z thread of the WARP PIC code. We describe the code and our model of the impedance due to the accelerating modules of the induction LINAC as a resistive wall. We present computer simulations which illustrate this instability. 2 refs., 2 figs., 1 tab.
Date: February 22, 1991
Creator: Callahan, D. A.; Langdon, A. B.; Friedman, A.; Grote, D. P. & Haber, I.
Partner: UNT Libraries Government Documents Department
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Diagnostics for the 400 MeV FNAL Linac

Description: The last four 201 MHz alvarez tanks of the twenty-year-old, 200 MeV Fermilab Linac are being replaced by seven high-gradient (7 KV/m), high-frequency (805 MHz) side-coupled-cavity structures to produce a 400 MeV beam for injection into the Booster. Good, reliable beam diagnostics are an important factor in the success of this project. This paper discusses the diagnostic systems.
Date: February 1, 1991
Creator: McCrory, E.S. & Lee, G.
Partner: UNT Libraries Government Documents Department
open access

The Fermilab Linac Upgrade

Description: The Fermilab Linac Upgrade is planned to increase the energy of the H- linac from 200 to 400 MeV. This is intended to reduce the incoherent space-charge tuneshift at injection into the 8 GeV Booster which can limit either the brightness or the total intensity of the beam. The Linac Upgrade will be achieved by replacing the last four 201.25 MHz drift-tube tanks which accelerate the beam from 116 to 200 MeV, with seven 805 MHz side-coupled cavity modules operating at an average axial field of abu… more
Date: February 1, 1991
Creator: Noble, R.J.
Partner: UNT Libraries Government Documents Department
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