Resource Type

Estimation of aerosol plutonium transport by the dust-flux method: a perspective on application of detailed data (open access)

Estimation of aerosol plutonium transport by the dust-flux method: a perspective on application of detailed data

Two methods of dust-flux measurements are discussed which have been utilized to estimate aerosol plutonium deposition and resuspension. In previous studies the methods were found to be sufficiently detailed to permit parameterization of dust-flux to the erodibility of the soil, and a seventh-power dependency of dust-flux (or plutonium flux) to wind speed was observed in worst case conditions. The eddy-correlation method is technically more difficult, requires high-speed data acquisition, and requires an instrument response time better than one second, but the eddy-correlation method has been shown feasible with new fast-response sensors, and it is more useful in limited areas because it can be used as a probe. The flux-gradient method is limited by critical assumptions and is more bulky, but the method is more commonly used and accepted. The best approach is to use both methods simultaneously. It is suggested that several questions should be investigated by the methods, such as saltation stimulation of dust-flux, simultaneous suspension and deposition, foliar deposition and trapping, erodibility of crusted surfaces, and horizontally heterogeneous erodibility.
Date: December 10, 1976
Creator: Shinn, Joseph H.
System: The UNT Digital Library
Application of proton radiography to medical imaging (open access)

Application of proton radiography to medical imaging

The use of charged particles for radiographic applications has been considered for some time, but progress has been impeded by the cost and availability of suitable accelerators. However, recent developments in technology could overcome these problems. A review is presented of the physical principles leading to an improvement in mass resolution per unit of absorbed dose for charged particle radiography relative to x-ray radiography. The quantitative comparisons between x-ray and proton radiographs presented here confirm this advantage. The implications of proton radiography on cancer detection, as well as future plans for developing a proton tomographic system, are discussed.
Date: December 1, 1977
Creator: Kramer, S. L.; Martin, R. L.; Moffett, D. R. & Colton, E.
System: The UNT Digital Library
Heat-treatment, microstructure and mechanical properties of experimental high strength Fe--4Cr--0. 4C steels (open access)

Heat-treatment, microstructure and mechanical properties of experimental high strength Fe--4Cr--0. 4C steels

The treatments involve high temperature (1100/sup 0/C) austenitizing during the first solution treatment followed by either interrupted quenching (Ms-Mf range) or isothermal transformation to produce lower bainite. Finally, the steels are given a 900/sup 0/C grain refinement treatment. Lower bainite was obtained by isothermally transforming austenite just above the Ms temperature. Tempering after the martensitic and bainitic treatments was also done in an attempt to improve the toughness of the material. The strength and toughness properties of as-quenched martensitic structures are somewhat superior while these properties of lower bainitic structures are comparable to those of a plain 0.4C steel. The properties of the nearly 100 percent bainite structure were unaffected by the cooling rate from the transformation temperature. Elimination of intergranular cracking produced toughness properties in quenched and tempered martensites which are far superior to those of lower bainite at the same strength level. It has also been shown that the toughness properties of as-quenched double-treated steels are superior to single treated steels. The chromium appeared to have a strong influence on the nature and morphology of carbides, as the bainitic as well as the martensitic structures showed marked temper resistance in the tempering range 200 to 500/sup 0/C.
Date: December 1, 1975
Creator: Narasimha Rao, B. V.; Miller, R. W. & Thomas, G.
System: The UNT Digital Library
Temperature dependence of the threshold energy for Frenkel pair production in copper (open access)

Temperature dependence of the threshold energy for Frenkel pair production in copper

Resolvable interstitial Frank loops were grown in (110) foils of high purity copper in the HVEM. At 575/sup 0/K loops were grown at accelerating voltages as low as 275 kV, corresponding to an energy transfer of 12 eV. The considerable reduction in threshold energy from values measured at room temperature or below(e;g; 18 to 20 eV) is thought to be related to thermally activated escape from correlated recombination.
Date: December 1, 1976
Creator: Drosd, R.; Kosel, T. & Washburn, J.
System: The UNT Digital Library
Hadron production in relativistic heavy ion interactions and the search for the quark-gluon plasma (open access)

Hadron production in relativistic heavy ion interactions and the search for the quark-gluon plasma

The course starts with an introduction, from the experimentalist's point of view, of the challenge of measuring Relativistic Heavy Ion interactions. A review of some theoretical predictions for the expected signatures of the quark gluon plasma will be made, with a purpose to understand how they relate to quantities which may be experimentally measured. A short exposition of experimental techniques and details is given including charged particles in matter, momentum resolution, kinematics and Lorentz Transformations, calorimetry. Principles of particle identification including magnetic spectrometers, time of flight measurement. Illustrations using the E802 spectrometer and other measured results. Resolution smearing of spectra, and binning effects. Parent to daughter effects in decay, with {pi}{sup 0} {yields} {gamma} {gamma} as an example. The experimental situation from the known data in p -- p collisions and proton-nucleus reactions is reviewed and used as a basis for further discussions. The Cronin Effect'' and the Seagull Effect'' being two arcana worth noting. Then, selected experiments from the BNL and CERN heavy ion programs are discussed in detail. 118 refs., 45 figs.
Date: December 1, 1989
Creator: Tannenbaum, M. J.
System: The UNT Digital Library
Laser irradiation of thin plastic targets with a 10. 6. mu. m CO/sub 2/ laser (open access)

Laser irradiation of thin plastic targets with a 10. 6. mu. m CO/sub 2/ laser

Polyethylene foils and parylene disks 5 to 10 ..mu..m thick have been irradiated by CO/sub 2/ laser pulses focused to flux levels in the 10/sup 13/ to 10/sup 14/ W/cm/sup 2/ range. The facility and the results obtained on these experiments are compared to similar targets hit with 1.06 ..mu.. pulses of like intensity. A CO/sub 2/ laser system, ''Valkyrie,'' fabricated from commercially available components was assembled for these experiments.
Date: December 1, 1975
Creator: Manes, K. R.; Haas, R. A.; Rupert, V. C. & Boyle, M. J.
System: The UNT Digital Library
Sampling a two-phase geothermal brine flow for chemical analysis (open access)

Sampling a two-phase geothermal brine flow for chemical analysis

An experiment designed primarily to define the problems associated with sampling the two-phase flow in a pipeline of geothermal brine is described. Analyses reported for 26 samples include chemical composition, oxidation potential, pH, density, and total solids. Changes in brine composition as the well operated during a four-week period are evaluated. The apparatus and techniques used for sampling are described and evaluated. (auth)
Date: December 5, 1975
Creator: Hill, J. H. & Morris, C. J.
System: The UNT Digital Library
Proceedings of the BNL workshop on physics with polarized targets, June 3--8, 1974 (open access)

Proceedings of the BNL workshop on physics with polarized targets, June 3--8, 1974

A separate entry was prepared for each of the 18 papers presented at the conference. (RCK)
Date: December 1, 1975
Creator: Russ, J. S.
System: The UNT Digital Library
Numerical model for land subsidence in shallow groundwater systems (open access)

Numerical model for land subsidence in shallow groundwater systems

A numerical model is presented to simulate compaction of shallow groundwater systems. The model combines a general three-dimensional fluid flow field with a one-dimensional deformation of the porous medium. The governing equation is solved with an Integrated Finite Difference Method using a mixed explicit-implicit iteration scheme for advancing in the time domain. The model can handle heterogeneous flow regions with complex geometry, and with time dependent variation of material properties and boundary conditions. Five illustrative examples are provided to demonstrate the applicability of the model to problems of relevance in studying land subsidence.
Date: December 1, 1976
Creator: Narasimhan, T. N. & Witherspoon, P. A.
System: The UNT Digital Library
Heavy fermion mass predictions and renormalization group equations (open access)

Heavy fermion mass predictions and renormalization group equations

It has recently become popular to predict the low energy fermion mass spectrum based on a high scale, M[sub x] [approximately] 10[sup 16] GeV/c[sup 2], ansatz for the Yukawa couplings. The evolution to low energy being achieved using renormalization group equations, with supersymmetry extant above a breaking scale M[sub s] [approx] 10[sup 3] GeV/c[sup 2]. In this paper it is shown how the heavy fermion and Higgs masses are determined by fixed points and thus will obtain in many specific models. This gives M[sub t] [approximately] 184 GeV/c[sup 2], M[sub h] [approximately] 122 GeV/c[sup 2] and imposing a hierarchy of scalar vacuum expectation values M[sub b] [approximately] 4.1, M[sub r] [approximately] 1.78 GeV/c[sup 2]. The dependence on [alpha][sub s], (M[sub z[degree]]) and M[sub s] is elucidated.
Date: December 1, 1992
Creator: Knowles, I. G. (Argonne National Lab., IL (United States)); Froggatt, C. D. & Moorhouse, G. (Glasgow Univ. (United Kingdom). Dept. of Physics and Astronomy)
System: The UNT Digital Library
Some design aspects of transuranic field studies (open access)

Some design aspects of transuranic field studies

In this paper we discuss some design aspects of transuranic field studies. Some of the principal steps in the design of such studies are given and illustrated using examples. This is followed by a review of sampling designs that have been used at nuclear detonation and safety-shot sites on the Nevada Test Site and elsewhere for estimating spatial pattern and total amounts in soil. Some design aspects of ecosystemtype transuranic studies for estimating total amounts as well as movement of transuranics between ecosystem components are also discussed. Acceptance sampling using either attributes or measurements is considered as a possible approach for deciding whether to clean up a contaminated site. Three general guidelines for the design of efficient transuranic studies are presented.
Date: December 1, 1976
Creator: Gilbert, R O & Eberhardt, L L
System: The UNT Digital Library
Transient fission gas release during direct electrical heating experiments (open access)

Transient fission gas release during direct electrical heating experiments

The gas release behavior of irradiated EBR-II fuel was observed to be dependent on several factors: the presence of cladding, the retained gas content, and the energy absorbed. Fuel that retained in excess of 16 to 17 ..mu..moles/g of fission gas underwent spallation as the cladding melted and released 22 to 45% of its retained gas, while fuel with retained gas levels below approx. 15 to 16 ..mu..moles/g released less than approx. 9% of its gas as the cladding melted. During subsequent direct electrical heating ramps, fuel that did not spall released an additional quantity of gas (up to 4 ..mu..moles/g), depending on the energy absorbed.
Date: December 1, 1983
Creator: Fenske, G. R.; Emerson, J. E. & Savoie, F. E.
System: The UNT Digital Library
Stability of high-brilliance synchrotron radiation sources (open access)

Stability of high-brilliance synchrotron radiation sources

This paper discusses the following topics: characteristics of synchrotron radiation sources; stability of the orbits; orbit control; nonlinear dynamic stability; and coherent stability and control. 1 ref., 5 figs., 1 tab. (LSP)
Date: December 1, 1989
Creator: Chattopadhyay, S.
System: The UNT Digital Library
National Waste Terminal Storage Program information meeting, December 7-8, 1976. [Slides only, no text] (open access)

National Waste Terminal Storage Program information meeting, December 7-8, 1976. [Slides only, no text]

Volume II of the report comprises copies of the slides from the talks presented at the second session of the National Waste Terminal Storage Program information meeting. This session was devoted to geologic studies. (LK)
Date: December 6, 1976
Creator: unknown
System: The UNT Digital Library
Proceedings of the Summer Study Meeting on Kaon Physics and Facilities. [Twenty-one papers] (open access)

Proceedings of the Summer Study Meeting on Kaon Physics and Facilities. [Twenty-one papers]

None
Date: December 1, 1976
Creator: Palevsky, H.
System: The UNT Digital Library
Computing unit: a measure of total computer utilization (open access)

Computing unit: a measure of total computer utilization

The basis on which charges are calculated for use of computers at LBL is explained. CPU time, I/O requirements, and memory utilized are among the primary factors considered. (RWR)
Date: December 7, 1976
Creator: Stevens, D. F. & White, H. S.
System: The UNT Digital Library
Plasma experiments with 1. 06-. mu. m lasers at the Lawrence Livermore Laboratory (open access)

Plasma experiments with 1. 06-. mu. m lasers at the Lawrence Livermore Laboratory

Recent laser fusion experiments at the Lawrence Livermore Laboratory have provided basic data concerning: laser beam propagation and absorption in high temperature plasmas, electron energy transport processes that transfer the absorbed laser energy to the high-density ablation region, the general fluid dynamic expansion and compression of the heated plasma, and the processes responsible for the production of 14-MeV neutrons during implosion experiments. Irradiation experiments were performed with Nd:YAG glass laser systems: the two-beam Janus (less than or equal to40 J/100 ps, approx.0.4 TW) and Argus (less than or equal to140 J, 35 ps, approx.4 TW), and the single beam Cyclops (less than or equal to70 J/100 ps, approx.0.7 TW). Two classes of targets have been used: glass microshells (approx.40 to 120 ..mu..m in diameter with approx.0.75-..mu..m-thick walls) filled with an equimolar deuterium-tritium mixture, and disks (approx.160 to 600 ..mu..m in diameter and approx. 10 ..mu..m thick) of several compositions. The targets were supported in vacuum (pressure less than or equal to10/sup -5/ Torr) by thin glass stalks. This paper reports on results related to the propagation, absorption, and scattering of laser light by both spherical and planar targets.
Date: December 20, 1976
Creator: Ahlstrom, H. G.; Holzrichter, J. F.; Manes, K. R.; Storm, E. K.; Boyle, M. J.; Brooks, K. M. et al.
System: The UNT Digital Library
Use of a Van de Graaff proton accelerator for neutron radiography (open access)

Use of a Van de Graaff proton accelerator for neutron radiography

A neutron radiographic capability has been established at the Pantex ERDA Plant. A 3 MeV Van de Graaff accelerator is being used to make neutron radiographs in order to observe defects of explosives encased in metal containers and ''O'' ring integrity.
Date: December 1, 1976
Creator: Cassidy, J. P.
System: The UNT Digital Library
Numerical simulation of reservoir compaction in liquid dominated geothermal systems (open access)

Numerical simulation of reservoir compaction in liquid dominated geothermal systems

A numerical model is introduced which simulates the effects of fluid production as well as reinjection on the vertical deformation of water dominated geothermal reservoirs. This program, based on an Integrated Finite Difference technique and Terzaghi's one-dimensional consolidation model, computes the transport of heat and water through porous media, and resulting pore volume changes. Examples are presented to show the effects of reservoir heterogeneities on the compaction of these hot water systems, as well as the effects of different production-injection schemes. The use of isothermal models to simulate the deformation of non-isothermal systems was also investigated.
Date: December 1, 1976
Creator: Lippmann, M. J.; Narasimhan, T. N. & Witherspoon, P. A.
System: The UNT Digital Library
High power semiconductor switching in the nanosecond regime (open access)

High power semiconductor switching in the nanosecond regime

Light activated multilayered silicon semiconductor devices have been used to switch at megawatt power levels with nanosecond turnon time. Current rate of rise of 700 kA/..mu..s at 10 kA, with 1 kV across the load have been achieved. Recovery time of 1 millisec has been obtained. Applicability to fusion research needs is discussed.
Date: December 1, 1975
Creator: Zucker, O. S.; Long, J. R.; Smith, V. L.; Page, D. J. & Roberts, J. S.
System: The UNT Digital Library
National Waste Terminal Storage Program information meeting, December 7-8, 1976. [Slides only, no text] (open access)

National Waste Terminal Storage Program information meeting, December 7-8, 1976. [Slides only, no text]

Volume I of the report comprises copies of the slides from the talks presented at the first session of the National Waste Terminal Storage Program information meeting. The agenda for the first day included an overview of the program plus presentations on such subjects as schedules and controls, facility projects, systems studies, regulatory affairs and technical support. (LK)
Date: December 1, 1976
Creator: unknown
System: The UNT Digital Library
Current performance and potential improvements in solar thermal industrial heat (open access)

Current performance and potential improvements in solar thermal industrial heat

A representive current state-of-the-art system using parabolic trough technology was developed using data from a system recently installed in Tehachapi, California. A simulation model was used to estimate the annual energy output from the system at three different insolation locations. Based on discussions with industry personnel and within NREL, we identified a number of technology improvements that offer the potential for increasing the energy performance and reducing the energy-cost of the baseline system. The technology improvements modeled included an evacuated-tube receiver, an antireflective coating on the receiver tube, an improved absorber material, a cleaner reflecting surface, a reflecting surface that can withstand contact cleaning, and two silver reflectors. The properties associated with the improvements were incorporated into the model simulation at the three insolation locations to determine if there were any performance gains. The results showed that there was a potential for a more am 50% improvement in the annual energy delivered by a 2677 m[sup 2] system incorporating a combination of the enumerated technology improvements. We discuss the commercial and technological status of each design improvement and present performance predictions for the trough-design improvements.
Date: December 1, 1992
Creator: Hale, M. J.; Williams, T. & Barker, G.
System: The UNT Digital Library
Combustion-generated indoor air pollution (open access)

Combustion-generated indoor air pollution

It is obvious from this study that elevated levels of gaseous air pollutants (CO, NO, NO/sub 2/, and SO/sub 2/) and particulate sulfur and nitrogen compounds are present in indoor environments with gas cooking and heating appliances. High levels of CO and NO/sub 2/ approach or exceed promulgated and proposed ambient air quality standards. Such findings certainly indicate a potential impact of combustion-generated indoor air pollution on human health; and if borne out by further work, they may ultimately have a large impact on the future design of epidemiological studies, on energy conservation strategies for buildings, and on the need for more stringent control of air pollution from indoor combustion sources.
Date: December 1, 1976
Creator: Hollowell, C. D.; Budnitz, R. J. & Traynor, G. W.
System: The UNT Digital Library
Clinical-radiological evaluation of sequelae of stereotactic radiosurgery for intracranial arteriovenous malformations (open access)

Clinical-radiological evaluation of sequelae of stereotactic radiosurgery for intracranial arteriovenous malformations

Stereotactic heavy-charged-particle Bragg peak radiosurgery has been used to treat 322 patients with surgically-inaccessible intracranial vascular malformations. (The clinical results of this method for the treatment of angiographically demonstrable arteriovenous malformations (AVMs) and angiographically occult vascular malformations (AOVMs) of the brain are described in separate reports of this symposium). The great majority of patients have had an uneventful post-treatment course with satisfactory health outcomes. However, several categories of delayed sequelae of stereotactic radiosurgery have been identified, involving the vascular structures essential for the integrity of the brain tissue and the brain parenchyma directly. These categories reflect both reaction to injury and to alterations in regional hemodynamic status, and include vasogenic edema, occlusion of functional vasculature, radiation necrosis, and local or remote effects on cerebral arterial aneurysms. 10 refs., 7 figs., 1 tab.
Date: December 1, 1989
Creator: Levy, R. P.; Fabrikant, J. I.; Frankel, K. A.; Phillips, M. H.; Steinberg, G. K.; Marks, M. P. et al.
System: The UNT Digital Library