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An IFE development strategy (open access)

An IFE development strategy

The development of inertial fusion as a power source will require achieving four principal milestones: ignition and propagating burn; high gain at low drive energy for the reactor driver; pulse repetition rates of a few Hz; and long-term reliability and economics of a reactor. To keep development time and costs to a minimum, these should be accomplished with as few major facilities as possible. A viable scenario for the Inertial Fusion Energy (IFE) Program would include establishing the first milestone in a Nova Upgrade for ignition and gain and the latter three in an upgradable, low-power Engineering Test Facility (ETF)/Demonstration Power Plant (DPP), i.e. two major facilities. To be successful in as short a time as possible operations at the major facilities would have to be supported by off-line reactor driver and other reactor technology development efforts. These efforts would evaluate and prioritize the myriad of options available at present for power plant and subsystem concepts. This paper describes the elements of such a program that could make the first commercial power available in the decade of the 2020s and estimates the resources needed. This program would be carried out in phases with major go/no-go decision points before each large …
Date: July 16, 1991
Creator: Hogan, W.J.; Storm, E. & Lindl, J.D.
System: The UNT Digital Library
Baryon inhomogeneity from the cosmic quark-hadron phase transition (open access)

Baryon inhomogeneity from the cosmic quark-hadron phase transition

We discuss the generation of inhomogeneity in the baryon-number density during the cosmic quark-hadron phase transition. We use a simple model with thin-wall phase boundaries and ideal-gas equations of state. The nucleation of the phase transition introduces a new distance scale into the universe which will be the scale of the generated inhomogeneity. We review the estimate of this scale. During the transition baryon number is likely to collect onto a layer at the phase boundary. These layers may in the end be deposited as small regions of very high baryon density. 21 refs., 1 fig.
Date: July 16, 1991
Creator: Kurki-Suonio, H.
System: The UNT Digital Library
International workshop of chromosome 19 (open access)

International workshop of chromosome 19

This document summarizes the workshop on physical and genetic mapping of chromosome 19. The first session discussed the major disease loci found on the chromosome. The second session concentrated on reference families, markers and linkage maps. The third session concentrated on radiation hybrid mapping, somatic cell hybrid panels, macro restriction maps and YACs, followed by cDNA and long range physical maps. The fourth session concentrated on compiling consensus genetic and physical maps as well as discussing regions of conflict. The final session dealt with the LLNL cosmid contig database and comparative mapping of homologous regions of the human and mouse genomes, and ended with a discussion of resource sharing. 18 refs., 2 figs. (MHB)
Date: September 16, 1991
Creator: Pericak-Vance, M.A. (Duke Univ. Medical Center, Durham, NC (United States). Div. of Neurology) & Carrano, A.J. (Lawrence Livermore National Lab., CA (United States))
System: The UNT Digital Library
Chamber propagation (open access)

Chamber propagation

Propagation of a heavy ion beam to the target appears possible under conditions thought to be realizable by several reactor designs. Beam quality at the lens is believed to provide adequate intensity at the target -- but the beam must pass through chamber debris and its self fields along the way. This paper reviews present consensus on propagation modes and presents recent results on the effects of photoionization of the beam ions by thermal x-rays from the heated target. Ballistic propagation through very low densities is a conservative mode. The more-speculative self-pinched mode, at 1 to 10 Torr, offers reactor advantages and is being re-examined by others. 13 refs.
Date: January 16, 1991
Creator: Langdon, B.
System: The UNT Digital Library
Chiral symmetry breaking in gauge theories from Reggeon diagram analysis (open access)

Chiral symmetry breaking in gauge theories from Reggeon diagram analysis

It is argued that reggeon diagrams can be used to study dynamical properties of gauge theories containing a large number of massless fermions. SU(2) gauge theory is studied in detail and it is argued that there is a high energy solution which is analogous to the solution of the massless Schwinger model. A generalized winding-number condensate produces the massless pseudoscalar spectrum associated with chiral symmetry breaking and a trivial'' S-Matrix.
Date: December 16, 1991
Creator: White, A. R.
System: The UNT Digital Library
The equation of state of liquid Flibe (open access)

The equation of state of liquid Flibe

Flibe (Li{sub 2}BeF{sub 4}) is a candidate material for the liquid blanket in the HYLIFE-2 fusion reactor. The thermodynamic properties of the material are important for the study of thermohydraulic behavior of the concept design, including the compressible analysis of the blanket isochoric heating problem and resulting jet breakup. The equation of state provides the relationship between all the thermodynamic properties. Previously, a soft sphere model of liquid equation of state was used for describing a number of liquid metals. In this paper we have fitted the available experimental data for liquid Flibe with a modified soft sphere model. 5 refs.
Date: August 16, 1991
Creator: Chen, Xiang M.; Schrock, V.E. & Peterson, P.F.
System: The UNT Digital Library
Vanadium alloys for structural applications in fusion systems: A review of vanadium alloy mechanical and physical properties (open access)

Vanadium alloys for structural applications in fusion systems: A review of vanadium alloy mechanical and physical properties

The current knowledge is reviewed on (1) the effects of neutron irradiation on tensile strength and ductility, ductile-brittle transition temperature, creep, fatigue, and swelling of vanadium-base alloys, (2) the compatibility of vanadium-base alloys with liquid lithium, water, and helium environments, and (3) the effects of hydrogen and helium on the physical and mechanical properties of vanadium alloys that are potential candidates for structural materials applications in fusion systems. Also, physical and mechanical properties issues are identified that have not been adequately investigated in order to qualify a vanadium-base alloy for the structural material in experimental fusion devices and/or in fusion reactors.
Date: December 16, 1991
Creator: Loomis, B. A. & Smith, D. L.
System: The UNT Digital Library
The analysis of the Flibe jets in HYLIFE-II (open access)

The analysis of the Flibe jets in HYLIFE-II

In the HYLIFE-2 Inertial Confinement Fusion reactor, an array of Flibe (Li{sub 2}BeFe{sub 4}) jets is designed to protect the chamber from the fusion radiation. During the fusion pulse the Flibe jets sustain an instantaneous neutron and X-ray heating. The high energy neutrons from fusion can penetrate deep into the Flibe jets and the sudden increase in internal energy can induce a great pressure rise inside the jets. The subsequent relaxation of the jets is important for the reactor design, because the configuration of the jets will control the subsequent impact forces of vapor and liquid on the reactor chamber wall. The calculations for the lithium jets in the HYLIFE-1 reactor were done previously by using a compressible flow model with a soft sphere equation of state for lithium. A similar equation of state model for Flibe was recently developed. This model allows us to use the same compressible analysis code to calculate the pressure field in the Flibe jets and to estimate the upper bound of the Flibe tension limit. With these results we can analyze the mechanisms of jet relaxation and breakup. 4 refs., 1 fig.
Date: August 16, 1991
Creator: Chen, Xiang M.; Schrock, V.E. & Peterson, P.F.
System: The UNT Digital Library
Analysis of time- and space-resolved Na-, Ne-, and F-like emission from a laser-produced bromine plasma (open access)

Analysis of time- and space-resolved Na-, Ne-, and F-like emission from a laser-produced bromine plasma

Advances in the efficiency and accuracy of computational atomic physics and collisional radiative modeling promise to place the analysis and diagnostic application of L-shell emission on a par with the simpler K-shell regime. Coincident improvements in spectroscopic plasma measurements yield optically thin emission spectra from small, homogeneous regions of plasma, localized both in space and time. Together, these developments can severely test models for high-density, high-temperature plasma formation and evolution, and non-LTE atomic kinetics. In this paper we present highly resolved measurements of n=3 to n=2 X-ray line emission from a laser-produced bromine micro-dot plasma. The emission is both space- and time-resolved, allowing us to apply simple, steady-state, 0-dimensional spectroscopic models to the analysis. These relativistic, multi-configurational, distorted wave collisional-radiative models were created using the HULLAC atomic physics package. Using these models, we have analyzed the F-like, Ne-like and Na-like (satellite) spectra with respect to temperature, density and charge-state distribution. This procedure leads to a full characterization of the plasma conditions. 9 refs., 3 figs.
Date: January 16, 1991
Creator: Goldstein, W.H.; Young, B.K.F.; Osterheld, A.L.; Stewart, R.E.; Walling, R.S. (Lawrence Livermore National Lab., CA (USA)); Bar-Shalom, A. (Israel Atomic Energy Commission, Beersheba (Israel). Nuclear Research Center-Negev) et al.
System: The UNT Digital Library
Chiral Symmetry Breaking in Gauge Theories From Reggeon Diagram Analysis (open access)

Chiral Symmetry Breaking in Gauge Theories From Reggeon Diagram Analysis

It is argued that reggeon diagrams can be used to study dynamical properties of gauge theories containing a large number of massless fermions. SU(2) gauge theory is studied in detail and it is argued that there is a high energy solution which is analogous to the solution of the massless Schwinger model. A generalized winding-number condensate produces the massless pseudoscalar spectrum associated with chiral symmetry breaking and a ``trivial`` S-Matrix.
Date: December 16, 1991
Creator: White, Alan R.
System: The UNT Digital Library
Vanadium alloys for structural applications in fusion systems: A review of vanadium alloy mechanical and physical properties (open access)

Vanadium alloys for structural applications in fusion systems: A review of vanadium alloy mechanical and physical properties

The current knowledge is reviewed on (1) the effects of neutron irradiation on tensile strength and ductility, ductile-brittle transition temperature, creep, fatigue, and swelling of vanadium-base alloys, (2) the compatibility of vanadium-base alloys with liquid lithium, water, and helium environments, and (3) the effects of hydrogen and helium on the physical and mechanical properties of vanadium alloys that are potential candidates for structural materials applications in fusion systems. Also, physical and mechanical properties issues are identified that have not been adequately investigated in order to qualify a vanadium-base alloy for the structural material in experimental fusion devices and/or in fusion reactors.
Date: December 16, 1991
Creator: Loomis, B. A. & Smith, D. L.
System: The UNT Digital Library
IOGCC/DOE oil and gas environmental workshop (open access)

IOGCC/DOE oil and gas environmental workshop

The Interstate Oil and Gas Compact Commission (IOGCC) in cooperation with US Department of Energy (DOE) has developed a workshop format to allow state regulatory officials and industry representatives the opportunity to participate in frank and open discussions on issues of environmental regulatory compliance. The purpose in providing this forum is to assist both groups in identifying the key barriers to the economic recoverability of domestic oil and gas resources while adequately protecting human health and the environment. The following topics were discussed, groundwater protection; temporarily abandoned and idle wells; effluent discharges; storm water runoff; monitoring and compliance; wetlands; naturally occurring radioactive materials; RCRA reauthorization and oil pollution prevention regulation. At the conclusion, all of the participants were asked to complete a questionnaire which critiqued the day activities. A discussion of each of the issues is made a part of this report as is a summary of the critique questionnaire which were received.
Date: May 16, 1991
Creator: unknown
System: The UNT Digital Library
Out-of-plane behavior of hollow clay tile walls infilled between steel frames (open access)

Out-of-plane behavior of hollow clay tile walls infilled between steel frames

Several buildings at Y-12 Plant rely on unreinforced hollow clay tile walls (HCTW) infilled between unbraced, non-moment resisting steel frames to resist natural phenomena forces, seismic and wind. One critical building relies on moment resisting steel frames in one direction while relying on unreinforced HCTWs infilled between the columns in the orthogonal direction to resist these forces. The HCTWs must act as shear walls while maintaining out-of-plane lateral stability. In assessing the safety of these buildings to seismic forces, several models to study the in- and out-of-plane effects were made and analyzed. The study of the moment resisting steel framed building indicated that bending stresses in the walls were induced by building drift and not by inertial forces per se. The discovery of this phenomenon was some what of a surprise in that the analysis performed is not typically used in design of these structures. The study indicated that the walls began to crack at their interface with the foundation at a low ``g`` level and that horizontal cracking at different elevations continued until the walls exhibited little bending resistance. This paper presents results of the study for out-of-plane behavior of unreinforced HCTWs infilled between adjacent moment resisting steel frames …
Date: August 16, 1991
Creator: Butala, M. B.; Jones, W. D. & Beavers, J. E.
System: The UNT Digital Library