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NEUTRON RADIOGRAPHY: A 1962 PROGRESS REPORT (open access)

NEUTRON RADIOGRAPHY: A 1962 PROGRESS REPORT

The possibility of improved detection discrimination between selected materials; the high absorption of several 1ight materials such as hydrogen, lithium, and boron; and the relatively low absorption of many heavy materials are some characteristics which make neutron radiographic inspection attractive as a complementary technique to xradiography. A study of neutron radiography is reported in which the emphasis has been placed upon determining many of the characteristics of various techniques for detecting neutron images. Characteristics of photographic detectors for thermal neutron images are outlined. (R.J.S.)
Date: August 17, 1962
Creator: Berger, Harold
System: The UNT Digital Library
PERTURBATION-THEORY RULES FOR COMPUTING THE SELF-ENERGY OPERATOR IN QUANTUM STATISTICAL MECHANICS (open access)

PERTURBATION-THEORY RULES FOR COMPUTING THE SELF-ENERGY OPERATOR IN QUANTUM STATISTICAL MECHANICS

Highly convenient rules are given for the general term in the time-independent perturbation-theory expansion for the self-energy operator of quantum statistical mechanics. The rules are derived by starting from the usual formalism involving time-dependent Green's functions. The well-known formulas for thermodynamic quantities in terms of the self-energy operator are included for completeness.
Date: December 17, 1962
Creator: Baym, Gordon & Sessler, Andrew M.
System: The UNT Digital Library
PROPERTIES OP LIQUID HELIUM-THREE IN THE TWO-BODY CORRELATION APPROXIMATION. I (open access)

PROPERTIES OP LIQUID HELIUM-THREE IN THE TWO-BODY CORRELATION APPROXIMATION. I

This is the first of two papers in which the low-temperature properties of liquid He{sup 3} are to be calculated in the thermodynamically consistent 'T-matrix' approximation. The set of coupled integral equations which are to be solved is exhibited in Part A of this paper. Part B of this paper is devoted to a preliminary, zero-temperature calculation which employs the additional approximations of using separable potentials and a noninteracting spectral function to define the interaction of two particles in the medium: the <T>{sub 0} approximation. In this approximation they obtain a spectral function for the quasi particles which they expect to display general features in common with those of the actual spectral function. Using this spectral function, they calculate the thermodynamic properties of the system and find that they compare favorably to those obtained in other calculations.
Date: November 17, 1965
Creator: Beck, Donald E. & Sessler, Andrew M.
System: The UNT Digital Library
[Newspaper Article: Harvey Girls Were Queens In Days When The Railroad Was King In The West] (open access)

[Newspaper Article: Harvey Girls Were Queens In Days When The Railroad Was King In The West]

Newspaper article published in the Lubbock Avalanche Journal detailing the life of Harvey Girls as well as the history of Fred Harvey and Harvey Houses.
Date: November 17, 1968
Creator: unknown
System: The Portal to Texas History
Summary of the Distribution of Plutonium in the Tissues of 12 Occupationally Exposed Workers (open access)

Summary of the Distribution of Plutonium in the Tissues of 12 Occupationally Exposed Workers

None
Date: September 17, 1971
Creator: Lagerquist, C. R.; Hammond, S. E.; Bokowski, D. L. & Hylton, D. B.
System: The UNT Digital Library
Approximate method for calculating the response of emplacement structures subjected to ground shock from underground nuclear detonations (open access)
Utilization of the noble gases in studies of underground nuclear detonations (open access)

Utilization of the noble gases in studies of underground nuclear detonations

From symposium on noble gases; Las Vegas, Nevada, USA (24 Sep 1973). The Livermore Gas Diagnostics Program employs a number of rare gas isotopes, both stable and radioactive, in its investigations of the phenomenology of underground nuclear detonations. Radioactive gases in a sample are radiochemically purified by elution chromatography, and the separated gases are radioassayed by gamma-ray spectrometry and by internal or thin-window beta proportional counting. Concentrations of the stable gases are determined by mass-spectrometry, following chemical removal of the reactive gases in the sample. The most general application of the noble gases is as device fraction indicators to provide a basis for estimating totals of chimney-gas components. All of the stable rare gases except argon have been used as tracers, as have /sup 127/Xe and /sup 85/Kr. /sup 37/Ar and /sup 85/Kr have proven to be of particular value in the absence of a good tracer material as reference species for studies of chimney-gas chemistry. The rate of mixing of chimney gases and the degree to which the sampled gas truly represents the underground gas mixture can be studied with the aid of the fission- product gases. /sup 222/Ra and He are released to the cavity from the surrounding …
Date: September 17, 1973
Creator: Smith, C.F.
System: The UNT Digital Library
Geometry and heterogeneous effects on the neutronic performance of a Yin Yang mirror-reactor blanket (open access)

Geometry and heterogeneous effects on the neutronic performance of a Yin Yang mirror-reactor blanket

From 5th symposium on engineering problems of fusion research; Princeton, New Jersey, USA (6 Nov 1973). Two-dimensional models and Monte Carlo neutron transport techniques were used to calculate the tritium breeding and energy generation in a mirror-reactor blanket. Results indicate that blanket performance should be quite insensitive to variations in overall geometry as long as there are no large neutron-leakage paths. Injection and leakage penetration can be accommodated as long as the first-wall peneiration area subtends less than 25% of the first wall's spherical area. Heterogeneous and streaming effects in a tubular blanket can be important, but are negligible for closely packed arrays of tubes. The one-dimensional homogeneous spherical-shell model appears to be a useful tool for predicting performance of a tubular blanket conforming to the YinYang mirror geometry. (auth)
Date: October 17, 1973
Creator: Lee, J. D.
System: The UNT Digital Library
Numerical simulation of the high density approach to laser-fusion (open access)

Numerical simulation of the high density approach to laser-fusion

From joint meetlng of the American Nuclear Society and the Atomic Industrial Forum and Nuclear Energy Exhibition; San Francisco, California, USA (11 Nov 1973). Physical processes important to laser-fusion are discussed along with the models of these processes used by the LASNEX code. Arguments are presented to show the validity of diffusion theory and calculational results are compared to a more detailed transport method and to several experimental observations. A study of stabillty and symmetry results in a full two- dimensional calculation of a typical laser-fusion pellet. (auth)
Date: October 17, 1973
Creator: Zimmerman, G.V.
System: The UNT Digital Library
Physics of mirror reactors and devices (open access)

Physics of mirror reactors and devices

BS>From surface effects in controlled thermonuclear fusion devices and reactors Meeting; Argonne, Illinois, USA (10 Jan 1974). The physics of plasma confinement using the magnetic mirror principle is discussed, and the unique features of the mirror reactor approach to fusion are discussed and compared to the toroidal confinement approach. (auth)
Date: January 17, 1974
Creator: Moir, Ralph W.
System: The UNT Digital Library
Surface requirements for electrostatic direct energy converters (open access)

Surface requirements for electrostatic direct energy converters

From surface effects in controlled thermonuclear fusion devices and reactors meeting; Argonne, Illinois, USA (10 Jan 1974). There are two major electrostatic direct energy converter concepts whlch will be discussed from the point of view of the surfaces. One is the Venetian blind concept and the other is the periodic electrostatic focusing concept. They are both of the direct collector type. Fluxes of D/sup +/, T/sup +/, He/sup ++/, electrons, and x-rays are given. Design consideration due to thermionic emission, secondary electron emission, and radiation cooling are discussed. A detailed discussion is devoted to breakdown physics, the voltages and electric field strengths that can be employed, and how surface deterioration may affect voltage holding due to He/sup ++/ bombardment blistering. (auth)
Date: January 17, 1974
Creator: Moir, R.W.; Barr, W.L. & Miley, G.H.
System: The UNT Digital Library
Proton--electron--positron Project: PEP (open access)

Proton--electron--positron Project: PEP

None
Date: May 17, 1974
Creator: Smith, L.
System: The UNT Digital Library
Tritium in the fusion engineering research facility (open access)

Tritium in the fusion engineering research facility

None
Date: May 17, 1974
Creator: Hickman, R. G.
System: The UNT Digital Library
Experimental studies of vibrationlike nuclei through their electromagnetic properties (open access)

Experimental studies of vibrationlike nuclei through their electromagnetic properties

None
Date: September 17, 1974
Creator: Meyer, R. A.
System: The UNT Digital Library
Use of probabilistic techniques in designing pipes and pressure vessels (open access)

Use of probabilistic techniques in designing pipes and pressure vessels

None
Date: December 17, 1974
Creator: Wells, J.E.
System: The UNT Digital Library
Tritium toxicity: increased relative biological effectiveness of $sup 3$HOH with protraction of exposure (open access)

Tritium toxicity: increased relative biological effectiveness of $sup 3$HOH with protraction of exposure

None
Date: March 17, 1975
Creator: Dobson, R.L.; Arrington, J.H. & Kwan, T.C.
System: The UNT Digital Library
Evaluation of the use of sludge containing plutonium as a soil conditioner for food crops (open access)

Evaluation of the use of sludge containing plutonium as a soil conditioner for food crops

An experiment was conducted to assess the potential hazard associated with the use of sludge containing plutonium as a soil conditioner for food crops. Conditions were chosen that would maximize exposure to the $sup 239$Pu in the sludge through resuspension and in plant content and thus approximated the maximum potential hazards due to the inhalation and ingestion pathways. The estimated 50-year radiation doses to the pulmonary region of the lung, bone, and liver based on the results of the inhalation experiment are 6 x 10$sup -4$ rem, 1.2 x 10$sup -3$ rem, and 0.55 x 10$sup -4$ rem, respectively. Similarly, the 50- year radiation doses attributable to ingestion of the sludge-grown vegetables were 2.2 x 10$sup -5$ rem to the bone and 1.5 x 10$sup -5$ rem to the liver. Thus, the inhalation pathway is the more critical of the two. The maximum permissible annual doses to the lungs, bone, and the liver for a member of the general public are 1.5, 3.0, and 1.5 rem, respectively. Thus, the maximum credible 50-year lung, bone, and liver dose commitments associated with the use of the $sup 239$Pu-contaminated sludge as a soil conditioner are approximately 4.0 x 10$sup -2$ percent of the …
Date: September 17, 1975
Creator: Myers, D. S.; Silver, W. J.; Coles, D. G.; Lamson, K. C.; McIntyre, D. R. & Mendoza, B.
System: The UNT Digital Library
Computer simulation of laser-driven implosion of DT-filled glass microballoons (open access)

Computer simulation of laser-driven implosion of DT-filled glass microballoons

The results of some experimental measurements of laser implosions are analyzed. Calculations are made of specific target irradiations and compared with experiments. A general description is given of exploding pushers and the physical processes involved are described. (MOW)
Date: October 17, 1975
Creator: Larsen, J. T.
System: The UNT Digital Library
Fabrication and characterization of laser fusion targets (open access)

Fabrication and characterization of laser fusion targets

The fabrication steps are examined for a complex glass target which is designated as a Ball-in-Plate or Saturn target. The Ball-in-Plate target consists of a hollow, D-T filled glass sphere mounted in a thin glass plate. The glass plate is coplaner with a diametral plane of the sphere.
Date: October 17, 1975
Creator: Hendricks, C. D.; Behymer, R. D.; Brown, J. A.; Heaton, G. W.; McCann, E. R. & Weinstein, B. W.
System: The UNT Digital Library
Models of electron conductivity which lead to ablation stabilization of fluid instabilities in laser-driven implosions (open access)

Models of electron conductivity which lead to ablation stabilization of fluid instabilities in laser-driven implosions

LASNEX calculations with a modified electron conductivity show the existence of a firepolishing stabilization effect. By modifying the thermal conductivity so that K $alpha$ T/sup n//rho/sup m/, one is able to construct a situation in which the electrons deposit their energy in a thin layer at the ablation surface and closely match the zero order solutions assumed earlier. The firepolishing effect appears to require that a significant fraction of the total pressure be due to the ablation process itself rather than the thermal pressure in the corona gas. It also requires KL approximately 1 where L is the scale height for decay of thermal perturbations generated at the ablation surface. For classical electron conductivity, because the thermal flux depends linearly on the grams/cm$sup 2$ necessary to stop the electrons, (1/rho) nabla rho approximately (1/T) nabla T near the ablation surface so that the pressure is nearly constant across the ablation surface. Hence there is no ablation pressure as such and no firepolishing effect for electron-driven implosions. (auth)
Date: October 17, 1975
Creator: Lindl, J.D. & Mead, W.C.
System: The UNT Digital Library
CO/sub 2/ laser ionization of very high lying valence states in atomic uranium (open access)

CO/sub 2/ laser ionization of very high lying valence states in atomic uranium

Results of recently concluded investigations of infrared laser induced photoionization of very high lying even parity levels in atomic uranium are presented. Behavior of both Rydberg and valence states is described.
Date: November 17, 1975
Creator: Paisner, J. A.; Solarz, R. W.; Carlson, L. R.; May, C. A. & Johnson, S. A.
System: The UNT Digital Library
High resolution autoionization spectra in atomic uranium (open access)

High resolution autoionization spectra in atomic uranium

High resolution (less than or equal to .5 cm/sup -1/) autoionization spectra of atomic uranium has been observed from newly identified odd parity levels between 32,660 and 34,165 cm/sup -1/. Photoionization cross sections are presented.
Date: November 17, 1975
Creator: Paisner, J. A.; Solarz, R. W.; Carlson, L. R.; May, C. A. & Johnson, S. A.
System: The UNT Digital Library
Observation of new levels for isotope separation in atomic uranium by multistep ionization (open access)

Observation of new levels for isotope separation in atomic uranium by multistep ionization

Over 100 new odd parity levels useful for isotope separation of U(I) were observed between 32,660--34,165 cm/sup -1/ using multistep photoionization. A tabulation of typical cross sections and radiative lifetimes for these states is given. The extension of this technique to mapping the spectra of other heavy atoms is discussed. (auth)
Date: November 17, 1975
Creator: Carlson, L. R.; Solarz, R. W.; Paisne, J. A.; Worden, E. F.; May, C. A. & Johnson, S. A.
System: The UNT Digital Library
Optimizing the mirror (fusion--fission) hybrid reactor for plutonium production (open access)

Optimizing the mirror (fusion--fission) hybrid reactor for plutonium production

An analytic model of the fusion components is used to generate a consistent set of fusion parameters, and component costs as parameters are varied. A model of the blanket, based on neutronic and thermal hydraulics, is then used to analyze the trade-offs of energy production vs plutonium production dictated by blanket type and management. An economic discussion of fuel cost is also given. (MOW)
Date: November 17, 1975
Creator: Lee, J. D.; Bender, D. J. & Moir, R. W.
System: The UNT Digital Library