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Modeling of a dissolution system for transuranic compounds (open access)

Modeling of a dissolution system for transuranic compounds

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({sup ++}) in a nitric acid solution, the transuranic oxides will dissolve and can be removed with the solution leaving the other insoluble oxides behind. The dissolution of the transuranic oxides by reactions with Ag({sup ++}) occurs due to further oxidation to higher valence states and the formation of soluble ions such as MO{sub 2}{sup +} and MO{sub 2}{sup ++}. 7 refs., 5 figs., 1 tab.
Date: February 1, 1991
Creator: Chiba, Z. & Dease, C.
System: The UNT Digital Library
Performance of fast reactor mixed-oxide fuels pins during extended overpower transients (open access)

Performance of fast reactor mixed-oxide fuels pins during extended overpower transients

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 objectives of the designated TOPI-1A through -1D tests were to establish the cladding breaching threshold and mechanisms, and investigate the thermal and mechanical effects of the transient on pin behavior. The tests were conducted in EBR-2, a normally steady-state reactor. The modes of transient operation in EBR-2 were described in a previous paper. Two ramp rates, 0.1%/s and 10%/s, were selected to provide a comparison of ramp-rate effects on fuel behavior. The test pins chosen for the series covered a range of design and pre-test irradiation parameters. In the first test (1A), all pins maintained their cladding integrity during the 0.1%/s ramp to 60% peak overpower. Fuel pins with aggressive designs, i.e., high fuel- smear density and/or thin cladding, were, therefore, included in the follow-up 1B and …
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))
System: The UNT Digital Library
The industrial consortium for the utilization of the geopressured-geothermal resource (open access)

The industrial consortium for the utilization of the geopressured-geothermal resource

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 a dozen geopressured well projects. An hydraulic turbine test will be conducted at Pleasant Bayou in Summer of 1991. Dr. Wayne Steele of Anglewood, TX, a retired medical doctor, is proposing to raise fresh water Australian lobsters in the Pleasant Bayou Well fire water pond. Additional projects such as catfish farming, crayfish, desalintion plant and agricultural greenhouse use of the resource heat are waiting in the wings'' for the DOE wells to become available for pilot use projects. 2 figs.
Date: February 15, 1991
Creator: Negus-de Wys, J.
System: The UNT Digital Library
Evaluation of aging of cast stainless steel components (open access)

Evaluation of aging of cast stainless steel components

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 presented. Aging kinetics are strongly influenced by the synergistic effects of other metallurgical reactions that occur in parallel with spinodal decomposition, i.e., clustering of Ni, Mo, and Si solute atoms and the nucleation and growth of G-phase precipitates in the ferrite phase. A number of methods are outlined for estimating aging embrittlement under end-of-life of life-extension conditions, depending on several factors such as degree of permissible conservatism, availability of component archive material, and methods of estimating and verifying the activation energy of aging. 33 refs., 6 figs., 3 tabs.
Date: February 1, 1991
Creator: Chung, H.M.
System: The UNT Digital Library
Standing-Wave Free-Electron Laser Two-Beam Accelerator (open access)

Standing-Wave Free-Electron Laser Two-Beam Accelerator

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 microwave amplitude and phase to errors in current and energy. It is found that phase errors due to current jitter are substantially reduced from previous versions of the TBA. Analytic scalings and numerical simulations are used to obtain an illustrative TBA parameter set.
Date: February 1, 1991
Creator: Sessler, Andrew M.; Whittum, D. H.; Wurtele, Jonathan S.; Sharp, W. M. & Makowski, M. A.
System: The UNT Digital Library
Component and system tests of the SLD Cerenkov Ring Imaging Detector (open access)

Component and system tests of the SLD Cerenkov Ring Imaging Detector

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 recirculated liquid C{sub 6}F{sub 14} and on the effects of CRID construction materials on electron lifetime. 9 refs., 11 figs.
Date: February 1, 1991
Creator: Antilogus, P.; Aston, D.; Bienz, T.; Bird, F.; Dasu, S.; Dolinsky, S. et al.
System: The UNT Digital Library
Conditioning of high gradient H sup - accelerating cavities (open access)

Conditioning of high gradient H sup - accelerating cavities

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.
System: The UNT Digital Library
The t-J model at small t/j: Numerical, perturbative, and supersymmetric results (open access)

The t-J model at small t/j: Numerical, perturbative, and supersymmetric results

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 a new conjecture regarding the staggered magnetization of higher-spin states in the two-dimensional Heisenberg model. We also discuss extrapolation of small-t/J results to high-{Tc} parameter values; in the two-hole ground states we find (t/J){sup {lambda}} behavior in the rms hole-hole separation, and an extrapolation to t/J = 3 gives a bulk-limit rms hole-hole separation of {approx} 7{angstrom}. 18 refs., 6 figs.
Date: February 1, 1991
Creator: Barnes, T.
System: The UNT Digital Library
Indirect detection of heavy supersymmetric dark matter (open access)

Indirect detection of heavy supersymmetric dark matter

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 refs., 2 figs.
Date: February 1, 1991
Creator: Kamionkowski, M. (Chicago Univ., IL (USA))/(Fermi National Accelerator Lab., Batavia, IL (USA))
System: The UNT Digital Library
Preliminary field demonstration of a fiber-optic TCE sensor. [Trichloroethylene (TCE)] (open access)

Preliminary field demonstration of a fiber-optic TCE sensor. [Trichloroethylene (TCE)]

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 chloroform. This sensor is currently under evaluation in monitoring well and vadose zone applications. In this paper, we describe the principles of the existing single measurement sensor technology and show preliminary field-test results. 3 refs., 8 figs.
Date: February 1, 1991
Creator: Angel, S.M.; Langry, K.; Roe, J.; Colston, B.W. Jr.; Daley, P.F. & Milanovich, F.P.
System: The UNT Digital Library
New acceleration schemes and technologies (open access)

New acceleration schemes and technologies

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.
System: The UNT Digital Library
Ultrahigh-energy particles from cosmic strings (open access)

Ultrahigh-energy particles from cosmic strings

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 gauge- and Higgs bosons of the underlying spontaneously broken gauge theory. Subsequent decay of these massive particles can give rise to energetic particles ranging up to an energy on the order of the mass of the original particles released from the defects. This may give us a natural'' mechanism of production of extremely energetic cosmic ray particles in the universe today, without the need for any acceleration mechanism. To illustrate this idea, I describe in detail the calculation of the expected ultrahigh-energy proton spectrum due to a specific process which involves collapse or multiple self-intersections of a class of closed cosmic string loops formed in a phase transition at a grand unification energy scale. I discuss the possibility that some of the highest-energy cosmic ray particles are of this origin. …
Date: February 1, 1991
Creator: Bhattacharjee, P. (Chicago Univ., IL (USA). Astronomy and Astrophysics Center Fermi National Accelerator Lab., Batavia, IL (USA))
System: The UNT Digital Library
Can non-Gaussian fluctuations for structure formation arise from inflation (open access)

Can non-Gaussian fluctuations for structure formation arise from inflation

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}) is linear. More complicated potential surfaces may be approximated by continuously joining various linear 1n V({phi}{sub j}) potentials. Typically, non-Gaussian fluctuations arise when one passes over several sharp ridges in the potential surface. One can input this richer class of initial conditions into N-body codes to see the effects on the large scale structure in the Universe. The cleanest test of non-Gaussian fluctuations will hopefully occur in the near future from large angle microwave background anisotropy experiments. 13 refs., 3 figs.
Date: February 1, 1991
Creator: Salopek, D.S.
System: The UNT Digital Library
Weak interactions and presupernova evolution (open access)

Weak interactions and presupernova evolution

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)
System: The UNT Digital Library
Review of negative hydrogen ion sources (open access)

Review of negative hydrogen ion sources

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 parameters and beam characteristics of these sources will be given. 32 refs., 13 figs.
Date: February 1, 1991
Creator: Schmidt, C.W.
System: The UNT Digital Library
Natural inflation (open access)

Natural inflation

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 density fluctuation spectrum is a non-scale-invariant power law, with extra power on large scales. 12 refs., 3 figs.
Date: February 1, 1991
Creator: Frieman, J.A.
System: The UNT Digital Library
Mixed field peronnel dosimetry: Part 1, High temperature peak characteristics of the reader-annealed TLD-600 (open access)

Mixed field peronnel dosimetry: Part 1, High temperature peak characteristics of the reader-annealed TLD-600

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. The peaks ratio (peaks 6--7/peaks 3--5) of TLD-600 is 0.15 for neutrons of any incident energy, 0.01 for {sup 137}Cs gammas, and 0.02 for M-150 x-rays. Based on the high temperature peak characteristics, a mixed field neutron-photon personnel dosimetry methodology using a single TLD-600 element was developed. The dosimetric method was evaluated in mixed {sup 238}PuBe + {sup 137}Cs fields with four neutron-gamma dose equivalent ratios, and the neutron, photon and total dose equivalent estimations are better than 20% except in one case. However, it was found that the neutron and photon dose equivalent estimations are sensitive to the neutron and photon peaks ratios, depending on the neutron-photon dose equivalent ratio and the neutron source in the mixed field. Therefore, a …
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))
System: The UNT Digital Library
Neutron dose equivalents at the Advanced Light Source: Calculation using the MORSE code vs estimated values (open access)

Neutron dose equivalents at the Advanced Light Source: Calculation using the MORSE code vs estimated values

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 and on a compilation of experimental and theoretical material relevant to shielding of electron accelerators. From the MORSE calculation, the total occupational dose equivalent rate in the center of the ALS mezzanine was found to be less than 1 mSv (100 mrem) per shift year (2000-hr), and the total environmental dose equivalent rate at the ALS boundary, 125 m from the storage-ring center, was found to be about 302 {mu}Sv (30 mrem) per year. A comparison of the dose equivalents shows that the calculated MORSE-code values agree well with those estimated by the empirical method. That is, dose equivalents obtained by the empirical methods are of the same order of magnitude as the corresponding MORSE values. 7 refs., 7 figs., 2 tabs.
Date: February 1, 1991
Creator: Sun, Rai-Ko S.
System: The UNT Digital Library
The status of fuel cell technology (open access)

The status of fuel cell technology

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.
System: The UNT Digital Library
DSP: A detailed spectroscopy postprocessor for H-, He-, and Li-like ions (open access)

DSP: A detailed spectroscopy postprocessor for H-, He-, and Li-like ions

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))
System: The UNT Digital Library
Upgrading the Fermilab Linac local control system (open access)

Upgrading the Fermilab Linac local control system

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.
System: The UNT Digital Library
Modeling the Longitudinal Wall Impedance Instability in Heavy Ion Beams Using an R-Z PIC Code (open access)

Modeling the Longitudinal Wall Impedance Instability in Heavy Ion Beams Using an R-Z PIC Code

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.
System: The UNT Digital Library
Diagnostics for the 400 MeV FNAL Linac (open access)

Diagnostics for the 400 MeV FNAL Linac

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.
System: The UNT Digital Library
The Fermilab Linac Upgrade (open access)

The Fermilab Linac Upgrade

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 abut 7.5 MV/m. This will allow acceleration to 400 MeV in the existing Linac enclosure. Each accelerator module will be driven with a klystron-based rf power supply. A prototype rf modulator has been built and tested at Fermilab, and a prototype 12 MW klystron is being fabricated by Litton Electron Devices. Fabrication of production accelerator modules is in progress. 8 figs., 4 tabs.
Date: February 1, 1991
Creator: Noble, R.J.
System: The UNT Digital Library