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Fuel cycle problems in fusion reactors (open access)

Fuel cycle problems in fusion reactors

Fuel cycle problems of fusion reactors evolve around the breeding, recovery, containment, and recycling of tritium. These processes are described, and their implications and alternatives are discussed. Technically, fuel cycle problems are solvable; economically, their feasibility is not yet known. (auth)
Date: January 13, 1976
Creator: Hickman, R. G.
System: The UNT Digital Library
Enrichment supply and technology outside the United States (open access)

Enrichment supply and technology outside the United States

This is a review of foreign uranium enrichment capacity and uranium isotope separation technology, based on news items and articles in the public literature. Tables are included presenting capacity plans, growth, sales, research and development, etc. (DLC)
Date: January 13, 1977
Creator: Levin, S. A. & Blumkin, S.
System: The UNT Digital Library
SEBREZ: an inertial-fusion-reactor concept (open access)

SEBREZ: an inertial-fusion-reactor concept

The neutronic aspects of an inertial fusion reactor concept that relies on asymmetrical neutronic effects to enhance the tritium production in the breeding zones have been studied. We find that it is possible to obtain a tritium breeding ratio greater than 1.0 with a chamber configuration in which the breeding zones subtend only a fraction of the total solid angle. This is the origin of the name SEBREZ which stands for SEgregated BREeding Zones. It should be emphasized that this is not a reactor design study; rather this study illustrates certain neutronic effects in the context of a particular reactor concept. An understanding of these effects forms the basis of a design technique which has broader application than just the SEBREZ concept.
Date: January 13, 1982
Creator: Meier, W. R.
System: The UNT Digital Library
Review of free electron laser theory and experiments (open access)

Review of free electron laser theory and experiments

A review of the major Free Electron Laser (FEL) experiments will be presented. These experiments are designed to produce radiation at wavelengths from the far infrared to the ultraviolet. Different categories of FELs (Compton, Raman, optical klystron, two stage, etc.), as well as the suitability of various types of electron accelerators to power FELs, will also be discussed. Potential applications of the FEL will be summarized.
Date: January 13, 1984
Creator: Prosnitz, D.
System: The UNT Digital Library
Parameter studies of candidate lattices for the 1-2 GeV synchrotron radiation source (open access)

Parameter studies of candidate lattices for the 1-2 GeV synchrotron radiation source

This document discusses the implications of various collective phenomena on the required performance of candidate lattices for the LBL 1 to 2 GeV Synchrotron Radiation Source. The performance issues considered include bunch length, emittance growth, and beam lifetime. In addition, the possible use of the 1 to 2 GeV Synchrotron Radiation Source as a high-gain FEL is explored briefly. Generally, the differences between lattices are minor. It appears that the most significant feature distinguishing the various alternatives will be the beam lifetime.
Date: January 13, 1986
Creator: Zisman, M. S.
System: The UNT Digital Library
Personnel neutron dosimetry using CR-39 foils (open access)

Personnel neutron dosimetry using CR-39 foils

We are using CR-39 foils for personnel nuetron dosimetry at the Lawrence Livermore National Laboratory. We have developed a three-step electrochemical etching procedure that includes low-frequency electrochemical etching at low frequency and at elevated temperatures. Our first etching step is at 60 Hz, 3000 V for 5 hours in a 60/sup 0/C oven using 6.5 N KOH. The second etching step consists of an additional 23-minute etch at 60/sup 0/C, 2.0 kHz, and 3000 V, which increases the track size and makes them relatively uniform in size. The final step is a 15-minute post etch at 60/sup 0/C, which gives the tracks a smoother appearance. The foils are etched in etch chambers that can etch up to 24 foils. Several of these chambers can be used simultaneously with a single power supply. These chambers are rugged and have been used daily for over a year. 8 refs., 6 figs., 1 tab.
Date: January 13, 1987
Creator: Hankins, D.E.; Homann, S. & Westermark, J.
System: The UNT Digital Library
Induction linear accelerators for commercial photon irradiation processing (open access)

Induction linear accelerators for commercial photon irradiation processing

A number of proposed irradiation processes requires bulk rather than surface exposure with intense applications of ionizing radiation. Typical examples are irradiation of food packaged into pallet size containers, processing of sewer sludge for recycling as landfill and fertilizer, sterilization of prepackaged medical disposals, treatment of municipal water supplies for pathogen reduction, etc. Volumetric processing of dense, bulky products with ionizing radiation requires high energy photon sources because electrons are not penetrating enough to provide uniform bulk dose deposition in thick, dense samples. Induction Linear Accelerator (ILA) technology developed at the Lawrence Livermore National Laboratory promises to play a key role in providing solutions to this problem. This is discussed in this paper.
Date: January 13, 1989
Creator: Matthews, Stephen M.
System: The UNT Digital Library
Report of the QCD Working Group (open access)

Report of the QCD Working Group

We discuss some current problems associated with the applications of QCD to event rates in high energy collisions. Emphasis is given to the current ambiguities and uncertainties that exist in estimates of signals and backgrounds. The production of jets and isolated photons at hadron colliders is discussed in some detail. The problems of jet definition are addressed. Some features of the events underlying the hard scattering process are discussed. 72 refs., 32 figs., 3 tabs.
Date: January 13, 1989
Creator: Hinchliffe, I. & Shapiro, M. D.
System: The UNT Digital Library
Symplectic methods in circular accelerators (open access)

Symplectic methods in circular accelerators

By now symplectic integration has been applied to many problems in classical mechanics. It is my conviction that the field of particle simulation in circular rings is ideally suited for the application of symplectic integration. In this paper, I present a short description symplectic tools in circular storage rings.
Date: January 13, 1994
Creator: Forest, E.
System: The UNT Digital Library
Development of a Transportable Vitrification System for Mixed Waste (open access)

Development of a Transportable Vitrification System for Mixed Waste

The US DOE through the Mixed Waste Integrated Program, has identified a need to move mixed waste vitrification technology from the laboratory to the field as rapidly as possible. A great deal of work over the last few years has shown the feasibility of immobilizing selected hazardous waste streams in a vitrified product. Lab-scale work has been extended to pilot-scale tests, usually with surrogates of the actual waste. DOE felt that the technology was mature enough to allow demonstration in the field, on actual wastes, with units that would be prototypic of full sized waste treatment equipment. To this end, DOE`s Office of Technology Development sponsored the Westinghouse Savannah River Company (WSRC) to specify, procure, test, and operate a field scale demonstration using mobile equipment. Oak Ridge Reservation was chosen as the initial location for the field demonstration and Martin Marietta Reservation was chosen as the initial location for the field demonstration and Martin Marietta Energy Systems (MMES) tasked with all permitting, site preparation, and field support activities. During September 1993, WSRC used a ``Vendor Forum`` to solicit preliminary proposals for the Transportable Vitrification System (TVS). A number of quality proposals were received and evaluated. A vendor was selected and …
Date: January 13, 1995
Creator: Whitehouse, J. C.; Jantzen, Carol M.; Bickford, D. F.; Kielpinski, A. L.; Helton, B. D. & Van Ryn, F.
System: The UNT Digital Library
Modeling precipitation from concentrated solutions with the EQ3/6 chemical speciation codes (open access)

Modeling precipitation from concentrated solutions with the EQ3/6 chemical speciation codes

One of the more important uncertainties of using chemical speciation codes to study dissolution and precipitation of compounds is the results of modeling which depends on the particular thermodynamic database being used. The authors goal is to investigate the effects of different thermodynamic databases on modeling precipitation from concentrated solutions. They used the EQ3/6 codes and the supplied databases to model precipitation in this paper. One aspect of this goal is to compare predictions of precipitation from ideal solutions to similar predictions from nonideal solutions. The largest thermodynamic databases available for use by EQ3/6 assume that solutions behave ideally. However, two databases exist that allow modeling nonideal solutions. The two databases are much less extensive than the ideal solution data, and they investigated the comparability of modeling ideal solutions and nonideal solutions. They defined four fundamental problems to test the EQ3/6 codes in concentrated solutions. Two problems precipitate Ca(OH){sub 2} from solutions concentrated in Ca{sup ++}. One problem tests the precipitation of Ca(OH){sub 2} from high ionic strength (high concentration) solutions that are low in the concentrations of precipitating species (Ca{sup ++} in this case). The fourth problem evaporates the supernatant of the problem with low concentrations of precipitating species. …
Date: January 13, 1995
Creator: Brown, L. F. & Ebinger, M. H.
System: The UNT Digital Library
Single parameter controls for nuclear criticality safety at the Oak Ridge Y-12 Plant (open access)

Single parameter controls for nuclear criticality safety at the Oak Ridge Y-12 Plant

At the Oak Ridge Y-12 Plant, there are numerous situations in which nuclear criticality safety must be assured and subcriticality demonstrated by some method other than the straightforward use of the double contingency principle. Some cases are cited, and the criticality safety evaluation of contaminated combustible waste collectors is considered in detail. The criticality safety evaluation for combustible collectors is based on applying one very good control to the one controllable parameter. Safety can only be defended when the contingency of excess density is limited to a credible value based on process knowledge. No reasonable single failure is found that will result in a criticality accident. The historically accepted viewpoint is that this meets double contingency, even though there are not two independent controls on the single parameter of interest.
Date: January 13, 1995
Creator: Baker, J.S. & Peek, W.M.
System: The UNT Digital Library
[1/2 HP Maytag Restoration] (open access)

[1/2 HP Maytag Restoration]

Article by Pettinger, Wesley E. about 1/2 HP Maytag Engine Restoration.
Date: January 13, 1997
Creator: Pettinger, Wesley E.
System: The UNT Digital Library
Anomalous gauge boson couplings (open access)

Anomalous gauge boson couplings

The measurement of anomalous gauge boson self couplings is reviewed for a variety of present and planned accelerators. Sensitivities are compared for these accelerators using models based on the effective Lagrangian approach. The sensitivities described here are for measurement of {open_quotes}generic{close_quotes} parameters {kappa}{sub V}, {lambda}{sub V}, etc., defined in the text. Pre-LHC measurements will not probe these coupling parameters to precision better than O(10{sup -1}). The LHC should be sensitive to better than O(10{sup -2}), while a future NLC should achieve sensitivity of O(10{sup -3}) to O(10{sup -4}) for center of mass energies ranging from 0.5 to 1.5 TeV.
Date: January 13, 1997
Creator: Barklow, T.; Rizzo, T. & Baur, U.
System: The UNT Digital Library
A high energy physics perspective (open access)

A high energy physics perspective

The status of the Standard model and role of symmetry in its development are reviewed. Some outstanding problems are surveyed and possible solutions in the form of additional {open_quotes}Hidden Symmetries {close_quotes} are discussed. Experimental approaches to uncover {open_quotes}New Physics{close_quotes} associated with those symmetries are described with emphasis on high energy colliders. An outlook for the future is given.
Date: January 13, 1997
Creator: Marciano, W. J.
System: The UNT Digital Library
QCD: Challenges for the future (open access)

QCD: Challenges for the future

Despite many experimental verifications of the correctness of our basic understanding of QCD, there remain numerous open questions in strong interaction physics and we focus on the role of future colliders in addressing these questions. We discuss possible advances in the measurement of {alpha}{sub s}, in the study of parton distribution functions, and in the understanding of low x physics at present colliders and potential new facilities. We also touch briefly on the role of spin physics in advancing our understanding of QCD.
Date: January 13, 1997
Creator: Burrows, P.; Dawson, S.; Orr, L. & Smith, W.H.
System: The UNT Digital Library
Solubility of Anthracene in Binary Alcohol + 3-Methoxy-1-butanol Solvent Mixtures (open access)

Solubility of Anthracene in Binary Alcohol + 3-Methoxy-1-butanol Solvent Mixtures

Article on the solubility of anthracene in binary alcohol + 3-methoxy-1-butanol solvent mixtures.
Date: January 13, 1997
Creator: McHale, Mary E. R.; Horton, Ann-Sofi M.; Padilla, Sandra A.; Trufant, Ashantè L.; De La Sancha, Noé U.; Vela, Ernesto et al.
System: The UNT Digital Library
Susy and Such (open access)

Susy and Such

In these lectures, the author discusses the theoretical motivation for supersymmetric theories and introduce the minimal low energy effective supersymmetric theory, (MSSM). I consider only the MSSM and its simplest grand unified extension here. Some of the other possible low-energy SUSY models are summarized. The particles and their interactions are examined in detail in the next sections and a grand unified SUSY model presented which gives additional motivation for pursuing supersymmetric theories.
Date: January 13, 1997
Creator: Dawson, S.
System: The UNT Digital Library
Effects of LWR coolant environments on fatigue lives of austenitic stainless steels. (open access)

Effects of LWR coolant environments on fatigue lives of austenitic stainless steels.

Fatigue tests have been conducted on Types 304 and 316NG stainless steels to evaluate the effects of various material and loading variables, e.g., steel type, strain rate, dissolved oxygen (DO) in water, and strain range, on the fatigue lives of these steels. The results confirm significant decreases in fatigue life in water. Unlike the situation with ferritic steels, environmental effects on Types 304 and 316NG stainless steel are more pronounced in low-DO than in high-DO water. Experimental results have been compared with estimates of fatigue life based on a statistical model. The formation and growth of fatigue cracks in air and water environments are discussed.
Date: January 13, 1998
Creator: Chopra, O. K.
System: The UNT Digital Library
Identification of root cause and abatement of vibration of monochromator. (open access)

Identification of root cause and abatement of vibration of monochromator.

Silicon crystal mirrors are used to reflect high-intensity X-ray beams. A large amount of heat is generated in each mirror. To minimize the effect of thermal expansion on the crystal mirrors, heat is removed by pumping liquid gallium (with a boiling point of 29.8 C) through passages in the crystal mirrors. During system operation, mirror motion should be kept to an acceptable level to avoid performance degradation. There are many potential sources of excitation to the crystal assembly; one such source is the flowing gallium. Two series of tests were performed earlier for a near-prototypical gallium cooling system (1-2). This paper describes a series of tests to measure the general vibration response characteristics of critical components in the monochromator system that contains the mirrors. The main objective of this work is to identify the root cause of vibration and to recommend general guidelines for abatement of vibration. This is achieved by performing many tests to understand the response characteristics under various conditions, by analysis of the response data, and by use of some theoretical considerations.
Date: January 13, 1998
Creator: Jendrzejczyk, J. A.
System: The UNT Digital Library
Ion beam deposition and surface characterization of thin multi-component oxide films during growth. (open access)

Ion beam deposition and surface characterization of thin multi-component oxide films during growth.

Ion beam deposition of either elemental targets in a chemically active gas such as oxygen or nitrogen, or of the appropriate oxide or nitride target, usually with an additional amount of ambient oxygen or nitrogen present, is an effective means of depositing high quality oxide and nitride films. However, there are a number of phenomena which can occur, especially during the production of multicomponent films such as the ferroelectric perovskites or high temperature superconducting oxides, which make it desirable to monitor the composition and structure of the growing film in situ. These phenomena include thermodynamic (Gibbsian), and oxidation or nitridation-driven segregation, enhanced oxidation or nitridation through production of a highly reactive gas phase species such as atomic oxygen or ozone via interaction of the ion beam with the target, and changes in the film composition due to preferential sputtering of the substrate via primary ion backscattering and secondary sputtering of the film. Ion beam deposition provides a relatively low background pressure of the sputtering gas, but the ambient oxygen or nitrogen required to produce the desired phase, along with the gas burden produced by the ion source, result in a background pressure which is too high by several orders of …
Date: January 13, 1998
Creator: Krauss, A. R.; Im, J.; Smentkowski, V.; Schultz, J.A.; Auciello, O.; Gruen, D.M. et al.
System: The UNT Digital Library
Long-distance final-state interactions and j/psi decay (open access)

Long-distance final-state interactions and j/psi decay

None
Date: January 13, 1998
Creator: Suzuki, Mahiko
System: The UNT Digital Library
Modeling tritium behavior in Li{sub 2}ZrO{sub 3}. (open access)

Modeling tritium behavior in Li{sub 2}ZrO{sub 3}.

Lithium metazirconate (Li{sub 2}ZrO{sub 3}) is a promising tritium breeder material for fusion reactors because of its excellent tritium release characteristics. In particular, for water-cooled breeding blankets (e.g., ITER), Li{sub 2}ZrO{sub 3} is appealing from a design perspective because of its good tritium release at low operating temperatures. The steady-state and transient tritium release/retention database for Li{sub 2}ZrO{sub 3} is reviewed, along with conventional diffusion and first-order surface resorption models which have been used to match the database. A first-order surface resorption model is recommended in the current work both for best-estimate and conservative (i.e., inventory upper-bound) predictions. Model parameters we determined and validated for both types of predictions, although emphasis is placed on conservative design predictions. The effects on tritium retention of ceramic microstructure, protium partial pressure in the purge gas and purge gas flow rate are discussed, along with other mechanisms for tritium retention which may not be dominant in the experiments, but may be important in blanket design analyses. The proposed tritium retention/release model can be incorporated into a transient thermal performance code to enable whole-blanket predictions of tritium retention/release during cyclic reactor operation. Parameters for the ITER driver breeding blanket are used to generate a numerical …
Date: January 13, 1998
Creator: Billone, M. C.
System: The UNT Digital Library
Recent advances in indirect drive ICF target physics at LLNL (open access)

Recent advances in indirect drive ICF target physics at LLNL

In preparation for ignition on the National Ignition Facility, the Lawrence Livermore National Laboratory� s Inertial Confinement Fusion Program, working in collaboration with Los Alamos National Laboratory, Commissariat a 1� Energie Atomique (CEA), and Laboratory for Laser Energetics at the University of Rochester, has performed a broad range of experiments on the Nova and Omega lasers to test the fundamentals of the NIF target designs. These studies have refined our understanding of the important target physics, and have led to many of the specifications for the NIF laser and the cryogenic ignition targets. Our recent work has been focused in the areas of hohlraum energetics, symmetry, shock physics, and target design optimization & fabrication.
Date: January 13, 1998
Creator: Bernat, T. P.; Collins, G. W.; Haan, S.; Hammel, B. A.; Landen, O. L.; MacGowan, B. J. et al.
System: The UNT Digital Library