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open access

Measurement of instantaneous shut-in pressure in crystalline rock

Description: A method is defined which was found useful, not only for determining the instantaneous shut-in pressure (ISIP) during fracture creation, but also for determining the pressure inside the fracture, near the exit and entrance wellbores, when a circulation of fluid through a fracture is taking place. The basic assumption of the Muskat method is that, after a short transient period, the shut-in pressure approaches an asymptotic value, Pa, in an exponential fashion, i.e., if Pa is subtracted from P a… more
Date: January 1, 1981
Creator: Aamodt, L. & Kuriyagawa, M.
open access

Important material considerations in INTOR

Description: A number of important material-related problems were identified and analyzed during the Phase-I study for INTOR. The first wall and divertor collector plate are subjected to severe normal and off-normal conditions. A melt layer is predicted to develop in a bare stainless steel wall under plasma disruptions. Graphite tiles will not melt but they introduce other serious uncertainties into the design. The design strategy for the divertor collector plate focused on separating the surface and high h… more
Date: January 1, 1981
Creator: Abdou, M. A.; Mattas, R. F. & Smith, D. L.
open access

Isotope-dilution mass spectrometry in the measurement of plutonium isotope half-lives

Description: Isotope-dilution mass spectrometry has been used at Los Alamos to measure the half-lives of /sup 239/Pu, /sup 240/Pu, and /sup 241/Pu. The latter was determined by measuring the rate of decrease of the /sup 241/Pu//sup 242/Pu ratio in an appropriate isotopic mixture over a period of several years. The half-lives of the two lighter isotopes are too long to be determined in this manner. They were determined by measuring the rate of production of the uranium daughter relative to a known added /sup… more
Date: January 1, 1981
Creator: Abernathey, R.M. & Marsh, S.F.
open access

Shear rigidity of spread stearic acid monolayers on water

Description: The effect of Al/sup 3 +/, Fe/sup 3 +/, Ca/sup 2 +/, and Mg/sup 2 +/ ions and of pH on the two-dimensional shear modulus of stearic acid spread on a water substrate was determined. A large shear modulus was displayed by the films when the subphase contained Al/sup 3 +/ and Fe/sup 3 +/ ions at the self buffered pH. With Fe/sup 3 +/ dissolved in the subphase, the film displayed a viscous relaxation when strained but no residual stress was observed. No effect was observed with the Ca/sup 2 +/ or M… more
Date: January 1, 1981
Creator: Abraham, B. M.; Ketterson, J. B.; Miyano, K. & Kueny, A.
open access

Stimulated Raman scattering and four-wave mixing: steady-state plane-wave analytic solutions

Description: The equations for plane-wave steady-state propagation of n fields interacting via four wave processes in a Raman medium have been known since at least 1962. Complete analytic solutions have only been found for the process of harmonic generation. However, solutions have been obtained in the gain regime assuming zero pump depletion. Assuming all fields satisfy the phase matching condition, general analytic solutions to these equations have been found. The solutions are complete in that they descr… more
Date: January 1, 1981
Creator: Ackerhalt, J. R.
open access

Self-focusing in SF/sub 6/

Description: It is shown by explicit calculation of previously published quasicontinuum model that the molecular susceptibility rapidly approaches zero as higher excited states of the molecule become populated. Hence the overtones of the ..nu../sub 3/-pumped mode are totally responsible for the self focusing effects in SF/sub 6/. The ..nu../sub 3/ ladder contribution to the susceptibility is calculated. The vibrational model is a classical triply degenerate anharmonic oscillator in the Cartesian basis with … more
Date: January 1, 1981
Creator: Ackerhalt, J. R. & Galbraith, H. W.
open access

Preparation of higher-actinide burnup and cross section samples. [LMFBR]

Description: A joint research program involving the United States and the United Kingdom was instigated about four years ago for the purpose of studying burnup of higher actinides using in-core irradiation in the fast reactor at Dounreay, Scotland. Simultaneously, determination of cross sections of a wide variety of higher actinide isotopes was proposed. Coincidental neutron flux and energy spectral measurements were to be made using vanadium encapsulated dosimetry materials in the immediate region of the b… more
Date: January 1, 1981
Creator: Adair, H. L.; Kobisk, E. H.; Quinby, T. C.; Thomas, D. K. & Dailey, J. M.
open access

Improved coupling of the conduction and flow equations in TRAC. [PWR]

Description: Recent nuclear-reactor-systems modeling efforts have been directed toward the development of computer codes capable of simulating transients in short computational times. For this reason, a stability enhancing two-stem method (SETS) has been applied to the two-phase flow equations in the Transient Reactor Analysis Code (TRAC) allowing the Courant limit to be violated. Unfortunately, the coupling between the wall conduction equation and the fluid-dynamics equations is performed semi-implicitly, … more
Date: January 1, 1981
Creator: Addessio, F.L.
open access

Nonequilibrium flashing model for rapid pressure transients. [PWR]

Description: A detailed, microscopic model for the nonequilibrium flashing of water is coupled to equations describing the bulk liquid state in order to calculate rapid pressure response to an induced liquid strain. The flashing model is predicated on the dynamics of a single bubble growing in an infinite liquid, and it encompasses both the inertia and conduction-limited regimes of bubble growth. The analysis is valid at high temperatures. It is not limited by the assumption of a thin thermal boundary layer… more
Date: January 1, 1981
Creator: Aguilar, F. & Thompson, S.
open access

Geothermal Well Completions in Cerro Prieto

Description: Geothermal well completion criteria have evolved from 1964 to this date. The evolution started with the common techniques used in oil-well completion and gradually changed to accommodate the parameters directly related to the mineralogic characteristics of the geothermal fluids. While acceptable completions can now be achieved, research techniques and data collection should be improved to optimize the procedures.
Date: January 1, 1981
Creator: Aguirre, B. D & Rivera, J. M. C.
open access

Geothermal Well Maintenance and Repair in Cerro Prieto

Description: When the first well is drilled at a geothermal field, procedures for the cleaning, repair, and control of wells should be established. This aspect will be increasingly important as more wells are drilled. Equipment, tools and techniques need to be improved to achieve economic and safe results. Different systems have been developed and applied in maintenance of wells, in problems of casing incrustations, repairs, plugging, and well control. These systems should be improved, even though they have… more
Date: January 1, 1981
Creator: Aguirre, B. D. & Blanco, F. V.
open access

Geothermal Drilling in Cerro Prieto

Description: To date, 71 geothermal wells have been drilled in Cerro Prieto. The activity has been divided into several stages, and, in each stage, attempts have been made to correct deficiencies that were gradually detected. Some of these problems have been solved; others, such as those pertaining to well casing, cement, and cementing jobs, have persisted. The procedures for well completion--the most important aspect for the success of a well--that were based on conventional oil well criteria have been imp… more
Date: January 1, 1981
Creator: Aguirre, B. D. & Garcia, G. S.
open access

Framework for Evaluating the Effectiveness of Nuclear-Safeguards Systems. [Aggregated Systems Model (ASM)]

Description: This paper describes an analytical tool for evaluating the effectiveness of safeguards that protect special nuclear material (SNM). The tool quantifies the effectiveness using several measures, including probabilities and expected times to detect and respond to malevolent attempts against the facility. These measures are computed for a spectrum of threats involving outsiders, insiders, collusion, falsification, and deceit. Overall system effectiveness is judged using performance indices aggrega… more
Date: October 20, 1981
Creator: Al-Ayat, R. A. & Judd, B. R.
open access

Mapping of functional activity in brain with /sup 18/F-fluoro-deoxyglucose

Description: A model has been designed based on the assumptions of a steady state for glucose consumption, a first-order equilibration of the free /sup 14/C-DG pool in the tissue with the plasma level, and relative rates of phosphorylation of /sup 14/C-DG and glucose determined by their kinetic constants for hexokinase reaction. Using an operational equation based on this model, the metabolic rates of glucose are calculated in various regions of brain (utilizing brain slices and autoradiography). /sup 14/C … more
Date: January 1, 1981
Creator: Alavi, A.; Reivich, M.; Greenberg, J. & Wolf, A.
open access

Data acquisition and experiment control system for high-data-rate experiments at the National Synchrotron Light Source

Description: A data acquisition and experiment control system for experiments at the Biology Small-Angle X-ray Scattering Station at the National Synchrotron Light Source has been developed based on a multiprocessor, functionally distributed architecture. The system controls an x-ray monochromator and spectrometer and acquires data from any one of three position-sensitive x-ray detectors. The average data rate from the position-sensitive detector is approx. 10/sup 6/ events/sec. Data is stored in a one mega… more
Date: November 1, 1981
Creator: Alberi, J.L. & Stubblefield, F.W.
open access

Microseismic activity observed during depressurization of an oil storage cavern in rock salt

Description: In November 1978, the Los Alamos National Laboratory installed a triaxial downhole geophone package at the Bryan Mound Strategic Petroleum Reserve, a salt dome near Freeport, Texas. Monitoring was for the purpose of detecting microseismic activity during the depressurization of one of the oil storage caverns. Seismic activity started soon after the start of depressurization, reached a peak 5 days later, and rapidly died off. Nineteen locatable microearthquakes with magnitudes between -1 and -2 … more
Date: January 1, 1981
Creator: Albright, J. & Pearson, C.
open access

Characterization of hot dry rock geothermal energy extraction systems

Description: The engineering of heat exchange systems by which geothermal heat can be efficiently extracted from hot impermeable rocks is studied. The system currently under investigation at Fenton Hill, New Mexico consists of a network of large fractures created through the hydraulic pressurization of a well penetrating hot basement rocks and subsequently intersected by a second well drilled to form a flow-thru system. Cool water pumped into the fractures through one well, once heated in the reservoir, ret… more
Date: January 1, 1981
Creator: Albright, James N. & Newton, Carl A.
open access

Review of characteristic methods used to solve the linear transport equation

Description: Characteristic methods used to solve the linear transport equation are reviewed. Characteristic methods are based upon the solution of the transport equation written in the form psi(s) = psi(s/sub 0/)e/sup -sigma/sub T/(s-s/sub 0/)/ + ..integral../sub s/sub 0///sup s/Q(t')e/sup -sigma/sub T/(s-t')/dt', where s is arc length along the characteristic. The methods of solution distinguish themselves in how the characteristics used for computation are selected and how the source term is approximated… more
Date: January 1, 1981
Creator: Alcouffe, R.E. & Larsen, E.W.
open access

Geological and geophysical signatures of the Jemez lineament: a reactivated Precambrian structure

Description: The Jemez lineament (N52/sup 0/E) is one of several northeast-trending lineaments that traverse the southwestern United States. It is defined by a 500-km-long alignment of late Cenozoic volcanic fields extending southwest from at least the Jemez Mountains in the north-central New Mexico to the San Carlos-Peridot volcanic field in east-central Arizona. Geochronologic data from Precambrian basement rocks indicate that the lineament is approximately coincident with a boundary between Precambrian c… more
Date: January 1, 1981
Creator: Aldrich, M. J., Jr.; Ander, M. E. & Laughlin, A. W.
open access

Development of multiampere negative ion sources

Description: The Neutral Beam Development Group at BNL is developing H-/D- surface plasma sources as part of a high energy neutral beam injector. Uncooled Penning and magnetron sources have operated at a maximum beam current of 1 A (10 ms pulses, Mk III) and a maximum pulse length of 200 ms (0.3 A, Mk IV). A magnetron source with focusing grooves on the cathode and an asymmetric anode-cathode geometry operates at a power efficiency of 8 kW/A and a 6% gas efficiency. As the next step, a water cooled magnetro… more
Date: January 1, 1981
Creator: Alessi, J.; Hershcovitch, A.; Prelec, K. & Sluyters, T.
open access

Negative ion beam formation, transport and acceleration

Description: The BNL Neutral Beam Development Group is working on the development of negative ion based neutral beam systems, using high current density surface plasma sources of the magnetron and hollow cathode discharge (HCD) type. With the magnetron source, the plan is to transport a 2A D/sup -/ beam through a bending magnet before acceleration to 200 keV. In experiments with a pulsed magnetron, 0.4A of H/sup -/ was transported through a 90/sup 0/, n = 1, bending magnet with 80% transmission. With the lo… more
Date: January 1, 1981
Creator: Alessi, J.G.
open access

BNL negative ion based neutral beam development

Description: The BNL Neutral Beam Development Group has as its objective the development of neutral beam systems, using negative ion sources with high current density. In this past year we have made the transition from pulsed high current negative ion sources to sources designed to operate steady state. We are presently testing two dc sources, a magnetron source and a modified magnetron with plasma injection from a hollow cathode discharge (HCD). Both sources have operated with steady state discharges; to d… more
Date: January 1, 1981
Creator: Alessi, J.G.; Hershcovitch, A.; Kovarik, V.; Larson, R.A.; McKenzie-Wilson, R.; Prelec, K. et al.
open access

Neutral beam development at BNL

Description: The long-term objective of the BNL Neutral Beam Development Group is to design and test a neutral beam system, using negative ion sources with a high beam current density. The principal elements of such a system are: a source of negative ions, beam extraction and transport system, accelerator, neutralizer, and the system for the removal and dumping (or energy recovery) of the remaining charged components of the beam. In the past year, a transition has been made from high current density, but pu… more
Date: January 1, 1981
Creator: Alessi, J.G.; Hershcovitch, A.; Kovarik, V.; Larson, R.A.; McKenzie-Wilson, R.; Prelec, K. et al.
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