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Detonation E. O. S. patterns for several explosives (open access)

Detonation E. O. S. patterns for several explosives

The available overdriven shockwave data for a number of explosives have been analyzed and compared. The data follow neither a constant gamma pattern nor the JWL EOS that fits expansion data to high accuracy. Modifications of the JWL function are proposed to correct for discrepancies and also to allow for the appropriate volume dependence of the Grueneisen constant indicated by previous and more recent work. The deviations from the JWL form of the equation of state appear directly above the CJ point for 9404 and PETN while Pentolite and TNT agree with this form over a portion of the Hugoniot. The comparisons with other experiments and a theoretical EOS indicate nonequilibrium behavior.
Date: July 13, 1983
Creator: Green, L.; Lee, E.L.; Mitchell, A.C.; Ree, F.; Tipton, R. & van Thiel, M.
System: The UNT Digital Library
Plasma-particle interaction effects in induction plasma modelling under dense loading conditions (open access)

Plasma-particle interaction effects in induction plasma modelling under dense loading conditions

The injection of solid particles or aerosol droplets in the fire-ball of an inductively coupled plasma can substantially perturb the plasma and even quench it under high loading conditions. This can be mainly attributed to the local cooling of the plasma by the particles or their vapour cloud, combined with the possible change of the thermodynamic and transport properties of the plasma in the presence of the particle vapour. This paper reports the state-of-the-art in the mathematical modelling of the induction plasma. A particle-in-cell model is used in order to combine the continuum approach for the calculation of the flow, temperature and concentration fields in the plasma, with the stochastic single particle approach, for the calculation of the particle trajectories and temperature histories. Results are given for an argon induction plasma under atmospheric pressure in which fine copper particles are centrally injected in the coil region of the discharge.
Date: July 1, 1983
Creator: Proulx, P.; Mostaghimi, J. & Boulos, M.
System: The UNT Digital Library
Roles of ionizing radiation in cell transformation (open access)

Roles of ionizing radiation in cell transformation

Earlier the authors described a repair misrepair model (RMR-I) which is applicable for radiations of low LET, e.g., x rays and gamma rays. RMR-II was described later. Here is introduced a mathematical modification of the RMR model, RMR-III, which is intended to describe lethal effects caused by heavily ionizing tracks. 31 references, 4 figures.
Date: July 1, 1983
Creator: Tobias, C. A.; Albright, N. W. & Yang, T. C.
System: The UNT Digital Library
Dynamic characteristic of intense short microwave propagation in an atmosphere (open access)

Dynamic characteristic of intense short microwave propagation in an atmosphere

The dynamic behavior of an intense microwave pulse which propagates through the atmosphere will be presented. Our theoretical results are obtained by solving Maxwell's equations, together with the electron fluid equations. Our calculations show that although large portions of the initial energy are absorbed by the electrons that are created through the avalanche process, a significant amount of energy is still able to reach the earth's surface. The amount of energy that reaches the earth's surface as a function of initial energy and wave shape after having propagated through 100 km in the atmosphere are investigated. Results for the air breakdown threshold intensity as a function of the pressure for different pulse widths and different frequencies will also be presented. In addition, we will present a comparison between the theoretical and the experimental results for the pulse shape of a short microwave pulse after it has traveled through a rectangular wave guide which contains a section of air. 23 references, 9 figures.
Date: July 1, 1983
Creator: Yee, J. H.; Alvarez, R. A.; Mayhall, D. J.; Madsen, N. K. & Cabayan, H. S.
System: The UNT Digital Library
Hugoniot Measurements in Vanadium Using the LNL Two-Stage Light-Gas Gun (open access)

Hugoniot Measurements in Vanadium Using the LNL Two-Stage Light-Gas Gun

Hugoniot measurements on vanadium have been made using the LLNL two-stage light-gas gun. The direct collision method with electrical pins and a tantalum flyer accelerated to 6.28 km/s was used. Alt'shuler, et. al., have reported Hugoniot measurements in vanadium using explosives and the impedance match method. They reported a kink in the U/sub s/ - U/sub p/ relationship at 183 GPa, and attribute it to electronic transitions. The upper portion of their curve is based on a single point at 339 GPa. The present work was performed to further investigate the equation-of-state in the high-pressure range.
Date: July 1, 1983
Creator: Gathers, G. R.; Mitchell, A. C. & Holmes, N. C.
System: The UNT Digital Library
Quantitative determination of minerals in Nevada Test Site samples by x-ray diffraction (open access)

Quantitative determination of minerals in Nevada Test Site samples by x-ray diffraction

The external standard intensity ratio technique has been developed into a routine procedure for quantitatively determining mineralogic compositions of Nevada Test Site (NTS) samples by x-ray diffraction. This technique used ratios of x-ray intensity peaks from the same run which eliminates many possible errors. Constants have been determined for each of thirteen minerals commonly found in NTS samples - quartz, montmorillonite, illite, clinoptilolite, cristobalite, feldspars, calcite, dolomite, hornblende, kaolinite, muscovite, biotite, and amorphous glass. Ratios of the highest intensity peak of each mineral to be quantified in the sample and the highest intensity peak of quartz are used to calculate sample composition. The technique has been tested on samples with three to eleven components representative of geologic environments at NTS, and is accurate to 7.0 wt % of the total sample. The minimum amount of each of these minerals detectable by x-ray diffraction has also been determined. QUANTS is a computer code that calculates mineral contents and produces a report sheet. Constants for minerals in NTS samples other than those listed above can easily be determined, and added to QUANTS at any time.
Date: July 1, 1983
Creator: Pawloski, G.A.
System: The UNT Digital Library
Novel neutralized-beam intense neutron source for fusion technology development (open access)

Novel neutralized-beam intense neutron source for fusion technology development

We describe a neutralized-beam intense neutron source (NBINS) as a relevant application of fusion technology for the type of high-current ion sources and neutral beamlines now being developed for heating and fueling of magnetic-fusion-energy confinement systems. This near-term application would support parallel development of highly reliable steady-state higher-voltage neutral D/sup 0/ and T/sup 0/ beams and provide a relatively inexpensive source of fusion neutrons for materials testing at up to reactor-like wall conditions. Beam-target examples described incude a 50-A mixed D-T total (ions plus neutrals) space-charge-neutralized beam at 120 keV incident on a liquid Li drive-in target, or a 50-A T/sup 0/ + T/sup +/ space-charge-neutralized beam incident on either a LiD or gas D/sub 2/ target with calculated 14-MeV neutron yields of 2 x 10/sup 15//s, 7 x 10/sup 15//s, or 1.6 x 10/sup 16//s, respectively. The severe local heat loading on the target surface is expected to limit the allowed beam focus and minimum target size to greater than or equal to 25 cm/sup 2/.
Date: July 8, 1983
Creator: Osher, J.E. & Perkins, L.J.
System: The UNT Digital Library
Search for Inclusive Oscillations of Muon Neutrinos in the Mass Range, 20 <. Delta. M/sup 2/ < 900 Ev/sup 2/ (open access)

Search for Inclusive Oscillations of Muon Neutrinos in the Mass Range, 20 <. Delta. M/sup 2/ < 900 Ev/sup 2/

A sensitive search for inclusive neutrino oscillations has been performed using two similar detectors running simultaneously at different locations in the Fermilab dichromatic muon-neutrino beam. The preliminary results show no significant oscillation signal and rule out inclusive oscillations of muon neutrinos into any other type of neutrons for 20 < ..delta..m/sup 2/ < 900 eV/sup 2/ and sin/sup 2/(2 theta) > 0.03 to 0.10.
Date: July 1, 1983
Creator: Haber, C.; Auchincloss, P.; Blair, R.; Ruiz, M.; Sciulli, F.; Shaevitz, M. et al.
System: The UNT Digital Library
Site selection (open access)

Site selection

The conditions and criteria for selecting a site for a nuclear weapons test at the Nevada Test Site are summarized. Factors considered are: (1) scheduling of drill rigs, (2) scheduling of site preparation (dirt work, auger hole, surface casing, cementing), (3) schedule of event (when are drill hole data needed), (4) depth range of proposed W.P., (5) geologic structure (faults, Pz contact, etc.), (6) stratigraphy (alluvium, location of Grouse Canyon Tuff, etc.), (7) material properties (particularly montmorillonite and CO/sub 2/ content), (8) water table depth, (9) potential drilling problems (caving), (10) adjacent collapse craters and chimneys, (11) adjacent expended but uncollapsed sites, (12) adjacent post-shot or other small diameter holes, (13) adjacent stockpile emplacement holes, (14) adjacent planned events (including LANL), (15) projected needs of Test Program for various DOB's and operational separations, and (16) optimal use of NTS real estate.
Date: July 1, 1983
Creator: Olsen, C.W.
System: The UNT Digital Library
Fluid and heat flow in gas-rich geothermal reservoirs (open access)

Fluid and heat flow in gas-rich geothermal reservoirs

Numerical-simulation techniques are used to study the effects of noncondensible gases (CO/sub 2/) on geothermal reservoir behavior in the natural state and during exploitation. It is shown that the presence of CO/sub 2/ has large effects on the thermodynamic conditions of a reservoir in the natural state, especially on temperature distributions and phase compositions. The gas will expand two-phase zones and increase gas saturations to enable flow of CO/sub 2/ through the system. During exploitation, the early pressure drop is primarily due to degassing of the system. This process can cause a very rapid initial pressure drop, on the order of tens of bars, depending upon the initial partial pressure of CO/sub 2/. The following gas content from wells can provide information on in-place gas saturations and relative permeability curves that apply at a given geothermal resource. Site-specific studies are made for the gas-rich two-phase reservoir at the Ohaki geothermal field in New Zealand. A simple lumped-parameter model and a vertical column model are applied to the field data. The results obtained agree well with the natural thermodynamic state of the Ohaki field (pressure and temperature profiles) and a partial pressure of 15 to 25 bars is calculated in the …
Date: July 1, 1983
Creator: O'Sullivan, M.J.; Bodvarsson, G.S.; Pruess, K. & Blakeley, M.R.
System: The UNT Digital Library
X-ray streak crystal spectography (open access)

X-ray streak crystal spectography

We have built an x-ray streaked crystal spectrograph for making time-resolved x-ray spectral measurements. This instrument can access Bragg angles from 11/sup 0/ to 38/sup 0/ and x-ray spectra from 200 eV to greater than 10 keV. We have demonstrated resolving powers, E/..delta..E > 200 at 1 keV and time resolution less than 20 psec. A description of the instrument and an example of the data is given.
Date: July 1, 1983
Creator: Kauffman, R.L.; Brown, T. & Medecki, H.
System: The UNT Digital Library
Monte Carlo sensitivity in jet studies - what is the physics (open access)

Monte Carlo sensitivity in jet studies - what is the physics

Tests of perturbative QCD in hard processes involving jets have been found to depend on the jet fragmentation model used. We emphasize the need for testing the factorization of hard and soft processes, i.e., the independent fragmentation of jets. A method of analysis is suggested, which allows a model-independent determination of the gluon fragmentation function from e/sup +/e/sup -/ data. We also comment on some simple features expected in anti pp ..-->.. (2 or 3 jets) + X events. 19 references.
Date: July 1, 1983
Creator: Hoyer, P.
System: The UNT Digital Library
Baryon-antibaryon angular correlations in quark jets (open access)

Baryon-antibaryon angular correlations in quark jets

The azimuthal angular distribution of baryon-antibaryon pairs in a quark jet is calculated and compared with experimental data in e/sup +/e/sup -/ annihilation.
Date: July 1, 1983
Creator: Bartl, A.
System: The UNT Digital Library
ECRH-transmission-system workshop (open access)

ECRH-transmission-system workshop

Abstracts and a listing of titles for each of the 18 papers are included. (MOW)
Date: July 1, 1983
Creator: unknown
System: The UNT Digital Library
Computer implementation, accuracy, and timing of radiation view-factor algorithms (open access)

Computer implementation, accuracy, and timing of radiation view-factor algorithms

The three-dimensional finite element thermal analysis of enclosure radiation problems requires the calculation of the geometric surface to surface radiation view factors. The view factors can be calculated by either area or line integration algortihms. This paper addresses the implementation, accuracy and computational time involved in using these algorithms. Additionally, an algorithm to identify shadowing surfaces and methods to adjust the calculated view factors for increased accuracy are presented.
Date: July 1, 1983
Creator: Shapiro, A. B.
System: The UNT Digital Library
Disparate changes in the physical properties of graphite. [HTGR] (open access)

Disparate changes in the physical properties of graphite. [HTGR]

The strength of graphite is rapidly degraded by small amounts of oxidation; thus, where graphite is used as a structural material (such as the core-support components of a High Temperature Gas-Cooled Reactor) it is highly desirable that the strength of these components can be assessed by nondestructive means. This author has shown that large disparate changes (either increases or decreases) in ultrasonic velocities, elastic moduli, and/or compressive strength can occur during the initial stages of oxidation; thereafter, the continued changes with oxidation are best-fit as a linear function of density. The purpose of this paper is to examine in more detail the disparate changes in the elastic moduli and compressive strength of oxidized graphite samples functions of density.
Date: July 1, 1983
Creator: Morgan, W. C.
System: The UNT Digital Library
Wake force computation in the time domain for long structures (open access)

Wake force computation in the time domain for long structures

One is often interested in calculating the wake potentials for short bunches in long structures using TBCI. For ultra-relativistic particles it is sufficient to solve for the fields only over a window containing the bunch and moving along with it. This technique reduces both the memory and the running time required by a factor that equals the ratio of the structure length to the window length. For example, for a bunch with sigma/sub z/ of one picosecond traversing a single SLAC cell this improvement factor is 15. It is thus possible to solve for the wakefields in very long structures: for a given problem, increasing the structure length will not change the memory required while only adding linearly to the CPU time needed.
Date: July 1, 1983
Creator: Bane, K. & Weiland, T.
System: The UNT Digital Library
Determination of subsurface geological structure with borehole gravimetry (open access)

Determination of subsurface geological structure with borehole gravimetry

Conventional gamma-gamma and gravimetric density measurements are routinely gathered for most holes used for underground nuclear tests. The logs serve to determine the subsurface structural geology near the borehole. The gamma-gamma density log measures density of the rock within about 15 cm of the borehole wall. The difference in gravity measured at two depths in a borehole can be interpreted in terms of the density of an infinite, homogeneous, horizontal bed between those depths. When the gravimetric density matches the gamma-gamma density over a given interval it is assumed that the bed actualy exists, and that rocks far from the hole must be the same as those encountered adjacent to the borehole. Conversely, when the gravimetric density differs from the gamma-gamma density it is apparent that the gravimeter is being influenced by a rock mass of different density than that at the hole wall. This mismatch can be a powerful tool to deduce the local structural geology. The geology deduced from gravity mesurements in emplacement hole, U4al, and the associated exploratory hole, UE4al, is an excellent example of the power of the method.
Date: July 1, 1983
Creator: Clark, S. R. & Hearst, J. R.
System: The UNT Digital Library
Charged-particle beam: a safety mandate (open access)

Charged-particle beam: a safety mandate

The Advanced Test Accelerator (ATA) is a recent development in the field of charged particle beam research at Lawrence Livermore National Laboratory. With this experimental apparatus, researchers will characterize intense pulses of electron beams propagated through air. Inherent with the ATA concept was the potential for exposure to hazards, such as high radiation levels and hostile breathing atmospheres. The need for a comprehensive safety program was mandated; a formal system safety program was implemented during the project's conceptual phase. A project staff position was created for a safety analyst who would act as a liaison between the project staff and the safety department. Additionally, the safety analyst would be responsible for compiling various hazards analyses reports, which formed the basis of th project's Safety Analysis Report. Recommendations for safety features from the hazards analysis reports were incorporated as necessary at appropriate phases in project development rather than adding features afterwards. The safety program established for the ATA project faciliated in controlling losses and in achieving a low-level of acceptable risk.
Date: July 15, 1983
Creator: Young, K.C.
System: The UNT Digital Library
Actinide-specific complexing agents: their structural and solution chemistry (open access)

Actinide-specific complexing agents: their structural and solution chemistry

The synthesis of a series of tetracatecholate ligands designed to be specific for Pu(IV) and other actinide(IV) ions has been achieved. Although these compounds are very effective as in vivo plutonium removal agents, potentiometric and voltammetric data indicate that at neutral pH full complexation of the Pu(IV) ion by all four catecholate groups does not occur. Spectroscopic results indicate that the tetracatecholates, 3,4,3-LICAMS and 3,4,3-LICAMC, complex Am(III). The Am(IV)/(III)-catecholate couple (where catecholate = 3,4,3-LICAMS or 3,4,3-LICAMC) is not observed, but may not be observable due to the large currents associated with ligand oxidation. However, within the potential range where ligand oxidation does not occur, these experiments indicate that the reduction potential of free Am(IV)/(III) is probably greater than or equal to + 2.6 V vs NHE or higher. Proof of the complexation of americium in the trivalent oxidation state by 3,4,3-LICAMS and 3,4,3-LICAMC elimates the possibility of tetracatholates stabilizing Am(IV) in vivo.
Date: July 1, 1983
Creator: Raymond, K. N.; Freeman, G. E. & Kappel, M. J.
System: The UNT Digital Library
Gyrotron user/developer meeting (open access)

Gyrotron user/developer meeting

A title listing is included for each of the 13 included papers. (MOW)
Date: July 1, 1983
Creator: unknown
System: The UNT Digital Library
Search and seizure law; practical advice and interpretation for nuclear protective force persons (open access)

Search and seizure law; practical advice and interpretation for nuclear protective force persons

Recent Supreme Court decisions, which interpret the 200-year-old Fourth Amendment of the US Constitution, are used to provide a brief overview of some search and seizure subjects important to management and officers responsible for physical protection of nuclear facilities. The overview is framed in practical terms in order to make the comments applicable to the everyday activity of nuclear-protective-force persons. The Supreme Court has described several exceptions where searches and seizures (arrests) are permitted without a warrant, despite the Fourth Amendment which states that warrants are always required. The seven exceptions briefly discussed are search incidents to a lawful arrest, the automobile-search exception, the suitcase or container exception, the hot-pursuit or emergency exception, the stop-and-frisk exception, the plain-view exception, and consent to be searched.
Date: July 6, 1983
Creator: Cadwell, J.J.
System: The UNT Digital Library
Intense positron beams and possible experiments (open access)

Intense positron beams and possible experiments

In this paper, we survey some of the ideas that have been proposed regarding the production of intense beams of low energy positrons. Various facilities to produce beams of this type are already under design or construction and other methods beyond those in use have been previously discussed. Moreover, a variety of potential experiments utilizing intense positron beams have been suggested. It is to be hoped that this paper can serve as a useful summary of some of the current ideas, as well as a stimulation for new ideas to be forthcoming at the workshop. 31 references.
Date: July 1, 1983
Creator: Lynn, K.G. & Frieze, W.E.
System: The UNT Digital Library
Microwave kinoform for magnetic fusion (open access)

Microwave kinoform for magnetic fusion

A microwave kinoform that modifies both the phase and polarization of an incident wavefront has been designed. This kinoform for the TMX-U magnetic fusion experiment has been fabricated and tested. The design procedure, method of fabrication, and experimental test results are discussed.
Date: July 19, 1983
Creator: Gallagher, N.C. Jr. & Sweeney, D.W.
System: The UNT Digital Library