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Comments on septa and other small production angle magnets

Description: A discussion is given of possible septum magnet parameters for small production angle experiments in the ISABELLE storage rings. Superconducting septa and torroidal septa are also considered. (PMA)
Date: August 25, 1977
Creator: Allinger, J.; Danby, G. & Jackson, J.
Partner: UNT Libraries Government Documents Department
open access

A cryogenic system design for the international thermonuclear experimental reactor (ITER)

Description: A conceptual design for ITER was completed last year. The author developed a suitable cryogenic system for ITER as part of this conceptual design effort. An overview of the design is reported. Emphasis is on the fact that cryogenics is a mature science, and a system supporting ITER needs can be made from time-proven components without loss of efficiency or reliability. Because of the large size of the ITER cryogenic system, large numbers of compressors and expanders must be used. Very high reli… more
Date: September 25, 1991
Creator: Slack, D.S.
Partner: UNT Libraries Government Documents Department
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Estimates of post-acceleration longitudinal bunch compression

Description: 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 appear… more
Date: November 25, 1977
Creator: Judd, D.L.
Partner: UNT Libraries Government Documents Department
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Algebraic calculation of stroboscopic maps of ordinary, nonlinear differential equations

Description: The relation between the parameters of a differential equation and corresponding discrete maps are becoming increasingly important in the study of nonlinear dynamical systems. Maps are well adopted for numerical computation and several universal properties of them are known. Therefore some perturbation methods have been proposed to deduce them for physical systems, which can be modeled by an ordinary differential equation (ODE) with a small nonlinearity. A new iterative, rigorous algebraic meth… more
Date: July 25, 1991
Creator: Wackerbauer, R. (Max-Planck-Institut fuer Extraterrestrische Physik, Garching (Germany)); Huebler, A. (Illinois Univ., Urbana, IL (United States). Center for Complex Systems Research) & Mayer-Kress, G. (Los Alamos National Lab., NM (United States) California Univ., Santa Cruz, CA (United States). Dept. of Mathematics)
Partner: UNT Libraries Government Documents Department
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Hybrid charged-particle guide for studying (n, charged particle) reactions

Description: Charged-particle transport systems consisting of magnetic quadrupole lenses have been employed in recent years in the study of (n, charged particle) reactions. We have completed a new transport system that is based both on magnetic lenses as well as electrostatic fields. The magnetic focusing of this charged-particle guide is provided by six magnetic quadrupole lenses arranged in a CDCCDC sequence (in the vertical plane). The electrostatic field is produced by a wire at high voltage which stret… more
Date: August 25, 1982
Creator: Haight, R. C.; White, R. M. & Zinkle, S. J.
Partner: UNT Libraries Government Documents Department
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Numerical simulation of the stability in a cable-in-conduit conductor developed for fusion-magnet applications

Description: The stability margins of the US-Demonstration Poloidal Coil (US-DPC) and the International Thermonuclear Experimental Reactor (ITER) TF coils have been modeled numerically using the computer program CICC. The computed US-DPC limiting current, I{sub lim}, compares favorably with the values determined experimentally. Using the detailed program CICC output, we investigated the DPC quench initiation mechanism in each of the three stability regions. In the ill-cooled region, the imposed heat pulse h… more
Date: September 25, 1991
Creator: Wong, R.L.; Shen, S.S. (Lawrence Livermore National Lab., CA (United States)); Yeaw, C.T. (Wisconsin Univ., Madison, WI (United States)) & Miller, J.R. (National High Magnetic Field Laboratory, Florida State University (USA))
Partner: UNT Libraries Government Documents Department
open access

Time-dependent properties of fiber composites for energy-storage flywheels

Description: Time-dependent deformation and time-dependent strength are being characterized for several candidate polymeric composites for flywheels. This presentation highlights the motivation and the philosophy of the characterization adopted by the authors in establishing the ongoing programs at LLL. This overview is intended to provide a basis for inferring the type of enginering data being generated for different aspects of flywheel design. The details of these data can be obtained from the published r… more
Date: October 25, 1977
Creator: Wu, E.M. & Penn, L.S.
Partner: UNT Libraries Government Documents Department
open access

Tritium experience at RTNS-II

Description: Neutrons are produced at the Rotating Target Neutron Source-II (RTNS-II) by deuteron bombardment of a rotating tritium target. Tritium is released from these targets into the accelerator vacuum system. The vacuum system exhaust is first scrubbed and then vented via the facility stack. Tritium emission from the facility in normal operation with vacuum system exhaust flowing through the scrubber is extremely low, <1 mCi/day. Releases from by-passing the tritium scrubber during roughing of the vac… more
Date: April 25, 1980
Creator: Logan, C. M.; Davis, J. C.; Gibson, T. A.; Heikkinen, D. W.; Schumacher, B. J. & Singh, M. S.
Partner: UNT Libraries Government Documents Department
open access

Production of muons for fusion catalysis in a magnetic mirror configuration. Revision 1

Description: For muon-catalyzed fusion to be of practical interest, a very efficient means of producing muons must be found. We describe a scheme for producing muons that may be more energy efficient than any heretofore proposed. There are, in particular, some potential advantages of creating muons from collisions of high energy tritons confined in a magnetic mirror configuration. If one could catalyze 200 fusions per muon and employ a uranium blanket that would multiply the neutron energy by a factor of 10… more
Date: July 25, 1986
Creator: Moir, R.W. & Chapline, G.F. Jr.
Partner: UNT Libraries Government Documents Department
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Supernovae, compact stars and nuclear physics

Description: We briefly review the current understanding of supernova. 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 12 times that of nuclear density to be stable against the most optimistic estimate of general relativistic inst… more
Date: August 25, 1989
Creator: Glendenning, N.K.
Partner: UNT Libraries Government Documents Department
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Current drive and heating systems for an ITER HARD option

Description: A conceptual design has been developed for a reference current drive and heating system for a HARD (High Aspect Ratio Design) option for ITER. Twelve neutral beam modules, each rated at 1.3MeV and 9.2MW, perform plasma heating and current drive. An electron cyclotron system is used for initiating the plasma and for disruption control. An alternate system has been defined which is comprised of a lower hybrid and ion cyclotron system for heating and current drive, augmented by the same electron c… more
Date: September 25, 1991
Creator: Lindquist, W.; Bulmer, R.; Fenstermacher, M.; Nevins, W.; Parker, J.; Smith, G. et al.
Partner: UNT Libraries Government Documents Department
open access

New tools using the hardware performance monitor to help users tune programs on the Cray X-MP

Description: The performance of a Cray system is highly dependent on the tuning techniques used by individuals on their codes. Many of our users were not taking advantage of the tuning tools that allow them to monitor their own programs by using the Hardware Performance Monitor (HPM). We therefore modified UNICOS to collect HPM data for all processes and to report Mflop ratings based on users, programs, and time used. Our tuning efforts are now being focused on the users and programs that have the best pote… more
Date: September 25, 1991
Creator: Engert, D. E.; Rudsinski, L. (Argonne National Lab., IL (United States)) & Doak, J. (Cray Research, Inc., Minneapolis, MN (United States))
Partner: UNT Libraries Government Documents Department
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Mirror theory applied to toroidal systems

Description: Central features of a mirror plasma are strong departures from Maxwellian distribution functions, ambipolar potentials and densities which vary along a field line, and losses, and the mirror field itself. To examine these features, mirror theorists have developed analytical and numerical techniques to solve the Fokker-Planck equation, evaluate the potentials consistent with the resulting distribution functions, and assess the microstability of these distributions. Various combinations of mirror… more
Date: August 25, 1987
Creator: Cohen, R.H.
Partner: UNT Libraries Government Documents Department
open access

First-Principles Theory of Correlated Transport through Nanojunctions

Description: Article on the first-principles theory of correlated transport through nanojunctions.
Date: March 25, 2005
Creator: Ferretti, A.; Calzolari, Arrigo; Di Felice, R.; Manghi, F.; Caldas, Marilia J.; Buongiorno Nardelli, Marco et al.
Partner: UNT College of Arts and Sciences
open access

Thermochemical Investigations of Solute Transfer into Ionic Solvents: Updated Abraham Model Equation Coefficients for Solute Activity Coefficient and Partition Coefficient Predictions

Description: Article on thermochemical investigations of solute transfer into ionic liquid solvents and updated Abraham model equation coefficients for solute activity coefficient and partition coefficient predictions.
Date: February 25, 2014
Creator: Stephens, Timothy W.; Chou, Vicky; Quay, Amanda N.; Shen, Connie; Dabadge, Nishu; Tian, Amy et al.
Partner: UNT College of Arts and Sciences
open access

Improving the injectability of high-salinity brines for disposal or waterflooding operations

Description: This work is part of a study conducted by Lawrence Livermore National Laboratory (LLNL) to improve the performance of brine injection wells at Gulf Coast Strategic Petroleum Reserve Sites. Our involvement established that granular media filtration, when used with proper chemical pretreatments, provides an effective and economical method for removing particulates from hypersaline brines. This treatment allows for the injection of 200,000 B/D with significantly increased well half-lives of 30 yea… more
Date: July 25, 1981
Creator: Raber, E.; Thompson, R.E. & Smith, F.H.
Partner: UNT Libraries Government Documents Department
open access

The soudan 2 experiment

Description: Soudan 2 is an 1100-ton tracking calorimeter which is being constructed to search for nucleon decay. The detector consists of finely segmented iron instrumented with drift tubes, and records three spatial coordinates and dE/dx for every gas crossing. Excellent event-reconstruction capability, particle identification, and muon sign and direction determination give superior rejection of the neutrino background to nucleon decay in many modes. The first 275 tons of Soudan 2 is operating and a charg… more
Date: May 25, 1989
Creator: Ayres, D.S.
Partner: UNT Libraries Government Documents Department
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Cancer risks and neutron RBE's from Hiroshima and Nagasaki

Description: The new radiation dose estimates for Hiroshima and Nagasaki are radiobiologically examined for compatability with other human and experimental data. The new doses show certain improvements over the original T65 doses. However, they suggest for chronic granulocytic leukemia, total malignancies, and chromosome aberrations, at neutron doses of 1 rad, RBEs in excess of 100, higher than expected from other findings. This and other indications suggest that either there are unrecognized systematic pro… more
Date: March 25, 1982
Creator: Dobson, R.L. & Straume, T.
Partner: UNT Libraries Government Documents Department
open access

Isotherms for the uranium-hydrogen system at temperatures of 700 to 1065/sup 0/C and pressures to 137. 89 MPa

Description: Pressure vs composition (P-C) isotherms for the UH system for temperatuers of 700 to 1065/sup 0/C and pressures to 137.89 MPa are shown. The sample was contained in a vessel concentric and located within a secondary vessel. Plateau pressure at 1065/sup 0/C is 700 atm. The single-phase region on the hydrogen-rich side starts at a H/U ratio of 2.35. Physical property measurements showed a thermal conductivity, k, value of 0.003 cal/cm sec K, R/sub c/ = 50. Experimentally determined plateau pressu… more
Date: June 25, 1985
Creator: Lakner, J. F.
Partner: UNT Libraries Government Documents Department
open access

Hydrodynamic effects in evaporating droplets

Description: The vaporization of a spherically symmetric liquid droplet homogeneously heated by a high-intensity laser pulse is investigated on the basis of a hydrodynamic description of the system composed of the vapor and ambient gas. In the limit of convective vaporization, the boundary conditions at the fluid-gas interface are formulated by using the notion of a Knudsen layer across which translational equilibrium is established. Numerical solutions to the hydrodynamic equations exhibit the existence of… more
Date: September 25, 1986
Creator: Armstrong, R.L. & Zardecki, A.
Partner: UNT Libraries Government Documents Department
open access

Magnetic mirror fusion program

Description: The past, present, and future thrusts of the magnetic mirror fusion program at LLL are reviewed. Neutral beam injection, stabilization, and density-lifetime product results from the 2XIIB experiment are briefly highlighted. The rationale of the Tandem Mirror Experiment and Field Reversed Mirror Experiment now under way are discussed. Plans for the Mirror Fusion Test Facility (MFTF) are described. Approaches to improvement of particle containment in mirror fusion systems are briefly indicated. (… more
Date: October 25, 1977
Creator: Fowler, T.K.
Partner: UNT Libraries Government Documents Department
open access

NFS, Kerberos, and UNICOS

Description: The Network File System (NFS) is used in UNIX-based networks to provide transparent file sharing between heterogeneous systems. Although NFS is well-known for being weak in security, it is widely used and has become a de facto standard. This paper examines the user authentication shortcomings of NFS and the approach Sandia National Laboratories has taken to strengthen it with Kerberos. The implementation on a Cray Y-MP8/864 running UNICOS is described and resource/performance issues are discuss… more
Date: September 25, 1991
Creator: Haynes, R.A.
Partner: UNT Libraries Government Documents Department
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