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DYNAVAC: a transient-vacuum-network analysis code (open access)

DYNAVAC: a transient-vacuum-network analysis code

This report discusses the structure and use of the program DYNAVAC, a new transient-vacuum-network analysis code implemented on the NMFECC CDC-7600 computer. DYNAVAC solves for the transient pressures in a network of up to twenty lumped volumes, interconnected in any configuration by specified conductances. Each volume can have an internal gas source, a pumping speed, and any initial pressure. The gas-source rates can vary with time in any piecewise-linear manner, and up to twenty different time variations can be included in a single problem. In addition, the pumping speed in each volume can vary with the total gas pumped in the volume, thus simulating the saturation of surface pumping. This report is intended to be both a general description and a user's manual for DYNAVAC.
Date: July 8, 1980
Creator: Deis, G.A.
Object Type: Report
System: The UNT Digital Library
Combination free-electron and gaseous laser (open access)

Combination free-electron and gaseous laser

A multiple laser having one or more gaseous laser stages and one or more free electron stages is described. Each of the free electron laser stages is sequentially pumped by a microwave linear accelerator. Subsequently, the electron beam is directed through a gaseous laser, in the preferred embodiment, and in an alternative embodiment, through a microwave accelerator to lower the energy level of the electron beam to pump one or more gaseous lasers. The combination laser provides high pulse repetition frequencies, on the order of 1 kHz or greater, high power capability, high efficiency, and tunability in the synchronous production of multiple beams of coherent optical radiation.
Date: June 8, 1981
Creator: Brau, C. A.; Rockwood, S. D. & Stein, W. E.
Object Type: Patent
System: The UNT Digital Library
Hadron-hadron physics at high energy and luminosity (open access)

Hadron-hadron physics at high energy and luminosity

I review some recent theoretical issues relevant to the physics of hadron-hadron collisions. I discuss processes where either energy or luminosity is the most important feature and emphasize the need for experiments at luminosities of 10{sup 33}cm{sup -2}sec{sup 1} if the full range of physics options is to be thoroughly explored. 22 refs., 10 figs.
Date: November 8, 1989
Creator: Hinchliffe, I.
Object Type: Article
System: The UNT Digital Library
[Memorandum from Jack Davis to Linus Wright, December 8, 1986] (open access)

[Memorandum from Jack Davis to Linus Wright, December 8, 1986]

Photocopy of a memorandum from Jack Davis, Office of the Provost and Vice President for Academic Affairs, to Linus Wright, Dallas ISD. Thanking Wright for his prompt response and letter of support of Dallas ISD participating as a consortium member in the planning a grant proposal, to be sent to the Getty Center for the Arts in Education. Davis is enclosing a copy of the proposal for Wright, which has already been submitted to the Getty. The Getty proposal not present with memorandum.
Date: December 8, 1986
Creator: Davis, Donald Jack
Object Type: Letter
System: The UNT Digital Library
Initial evaluation of photographic data of F- and H-Area seepage basin outcrops (open access)

Initial evaluation of photographic data of F- and H-Area seepage basin outcrops

Photographic data for the Savannah River Plant (SRP) were reviewed for 1961 through 1987 to determine the value of this photography in estimating the timing and extent of the F- and H-Area seepage basin outcrops along the upper Four Mile Creek floodplain. In excess of 15,000 frames of photography of the SRP were reviewed. The quality of the photography varied widely and included panchromatic (black and white), natural color, and false color infrared. Altitudes of the photography ranged from 2,000 feet above ground level (AGL) to 40,000 feet AGL. For each year the best photography at the lowest altitude was evaluated to determine the presence of vegetation damage downslope of the F- and H-Area seepage basins. Criteria of no visible evidence of vegetation (forest canopy) damage, initial evidence of vegetation or canopy damage, canopy thinning, tree mortality, and expansion of vegtation damage and/or tree mortality zones were applied to each of the photographs. In this initial evaluation, only the largest of the outcrops below the seepage basins were evaluated. (3 tabs.)
Date: February 8, 1988
Creator: Mackey, H. E., Jr.
Object Type: Report
System: The UNT Digital Library
Geometric continuum regularization of quantum field theory (open access)

Geometric continuum regularization of quantum field theory

An overview of the continuum regularization program is given. The program is traced from its roots in stochastic quantization, with emphasis on the examples of regularized gauge theory, the regularized general nonlinear sigma model and regularized quantum gravity. In its coordinate-invariant form, the regularization is seen as entirely geometric: only the supermetric on field deformations is regularized, and the prescription provides universal nonperturbative invariant continuum regularization across all quantum field theory. 54 refs.
Date: November 8, 1989
Creator: Halpern, M.B. (California Univ., Berkeley, CA (USA). Dept. of Physics)
Object Type: Article
System: The UNT Digital Library
Model of beam head erosion (open access)

Model of beam head erosion

An analytical model of beam head dynamics is presented, leading to an estimate of the erosion rate due to the combined effects of Ohmic dissipation and scattering. Agreement with the results of a computer simulation and detailed one-dimensional computations is good in all respects except for the scaling of the erosion rate with net current.
Date: August 8, 1980
Creator: Lee, Edward P.
Object Type: Report
System: The UNT Digital Library
Final focus nomenclature (open access)

Final focus nomenclature

The formal names and common names for all devices in the final focus system of the SLC are listed. The formal names consist of a device type designator, microprocessor designator, and a four-digit unit number. (LEW)
Date: August 8, 1986
Creator: Erickson, R.
Object Type: Report
System: The UNT Digital Library
Milliwatt generator heat source. Progress report, July-December 1981 (open access)

Milliwatt generator heat source. Progress report, July-December 1981

As part of the Milliwatt Generator (MWG) Program, a second series of pressure burst capsules welded offsite was tested; the resulting data indicate that the welds are very similar to those in the first series of capsules. Sufficient hardware was fabricated to meet all scheduled commitments. To provide a unit for feasibility testing, a heat source clad with Hastelloy C was reclad with Inconel 600. Forming development tests on Inconel 600 were conducted with favorable results. A QAS-3 survey was conducted and a satisfactory rating was received. Lot 11 qualification began on T-111 materials. The production period ended with an overall process yield of 99.6%, and a dollar percent defective rate of 0.60%.
Date: April 8, 1982
Creator: Mershad, E.A.
Object Type: Report
System: The UNT Digital Library
Demonstration of energy conservation for multi-deck board dryers. Phase I. Final report (open access)

Demonstration of energy conservation for multi-deck board dryers. Phase I. Final report

A study was made to determine the feasibility of recover and reuse of low level heat from the exhausts of multi-deck dryers used to dry boards in the building materials industry. There are approximately 1000 dryers of this type in the USA, with no heat recovery equipment. These dryers are used in the manufacture of: roof insulation board, ceiling tile and panel stock, wood fiber sheathing, gypsum board, and veneer plywood. Pilot scale tests and analyses show that heat recovery designs utilizing several types of heat exchange equipment are feasible. These include the following: indirect contact air-to-air heat exchangers for preheating combustion air for the dryer furnaces; direct contact air-to-water heat exchangers using water sprays to heat process water; and indirect contact air-to-liquid heat exchangers to heat recirculating liquid in a plant building heating system. The systems recommended for design and installation at the Rockdale plant include all three of the types of heat exchangers. The preliminary estimate for the installed cost for these systems at the Rockdale plant is $565,000 (1979 dllars). Annual heat recovery of 186,000 million Btu is projected with a value of $545,000 using gas costs of $3.00 per million Btu. Payback based on a discounted …
Date: February 8, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Laboratory-scale evaluations of alternative plutonium precipitation methods (open access)

Laboratory-scale evaluations of alternative plutonium precipitation methods

Plutonium(III), (IV), and (VI) carbonate; plutonium(III) fluoride; plutonium(III) and (IV) oxalate; and plutonium(IV) and (VI) hydroxide precipitation methods were evaluated for conversion of plutonium nitrate anion-exchange eluate to a solid, and compared with the current plutonium peroxide precipitation method used at Rocky Flats. Plutonium(III) and (IV) oxalate, plutonium(III) fluoride, and plutonium(IV) hydroxide precipitations were the most effective of the alternative conversion methods tested because of the larger particle-size formation, faster filtration rates, and the low plutonium loss to the filtrate. These were found to be as efficient as, and in some cases more efficient than, the peroxide method. 18 references, 14 figures, 3 tables.
Date: February 8, 1984
Creator: Martella, L. L.; Saba, M. T. & Campbell, G. K.
Object Type: Report
System: The UNT Digital Library
Imaging system for obtaining space- and time-resolved plasma images on TMX (open access)

Imaging system for obtaining space- and time-resolved plasma images on TMX

A Reticon 50 x 50 photodiode array camera has been placed on Livermore's Tandem Mirror Experiment to view a 56-cm diameter plasma source of visible, vacuum-ultraviolet, and x-ray photons. The compact camera views the source through a pinhole, filters, a fiber optic coupler, a microchannel plate intensifier (MCPI), and a reducer. The images are digitized (at 3.3 MHz) and stored in a large, high-speed memory that has a capacity of 45 images. A local LSI-11 microprocessor provides immediate processing and display of the data. The data are also stored on floppy disks that can be further processed on the large Livermore Computer System. The temporal resolution is limited by the fastest MCPI gate. The number of images recorded is determined by the read-out time of the Reticon camera (minimum 0.9 msec). The spatial resolution of approximately 1.4 cm is fixed by the geometry and the pinhole of 0.025 cm. Typical high-quality color representation of some plasma images are included.
Date: April 8, 1980
Creator: Koehler, H.A. & Frerking, C.E.
Object Type: Article
System: The UNT Digital Library
Development of copper sulfide/cadmium sulfide thin-film solar cells (open access)

Development of copper sulfide/cadmium sulfide thin-film solar cells

The most important accomplishments during this period were to demonstrate and to elucidate further the complex effects that occur during the aging of Cu/sub 2/S/CdS thin-film solar cells in flowing wet oxygen. There are two distinct effects. At constant illumination, the short-circuit current of cells aged at room temperature consistently decreases with time. The second effect, related to diode opposing current, is more involved and may result from several competing mechanisms. Over the short term (approx. 4 to 5 hours), the magnitude of diode opposing current decreases. After approx. 20 hours of aging, opposing current generally returns to the level achieved after hydrogen annealing which immediately preceded the aging sequence. Optical measurements of the spectral transmission of the Cu/sub 2/S layers in a cell content have been made using a silicon detector epoxied to the back of a CdS cell after the copper foil substrate was removed. There is no significant change in Cu/sub 2/S transmission behavior for wavelengths ranging from 525 to 1000 nm during wet-oxygen aging for periods of 2 to 36 hours. This suggests that the decrease in J/sub SC/ at constant illumination, for the aging experiments in a flowing wet-oxygen ambient, arises because of changes in …
Date: March 8, 1982
Creator: Szedon, J. R.; Biter, W. J. & Dickey, H. C.
Object Type: Report
System: The UNT Digital Library
Study of optical model parameters for high energy neutron cross sections from 5 to 50 MeV in the mass-140 region (open access)

Study of optical model parameters for high energy neutron cross sections from 5 to 50 MeV in the mass-140 region

A study of the neutron optical potential on nuclei near mass-140 was begun to extend the energy range and improve the precision of previous neutron total cross section measurements. The extended energy range of this measurement reveals maxima and minima in the total cross section that are evidence of the nuclear Ramsauer effect. A 100-MeV linear accelerator is used to produce a continuum of neutron energies from a Ta-Be conversion target. A 250-meter flight path is used to measure neutron energies by the time-of-flight method. Transmission data for /sup 140/Ce and transmission ratios for /sup 142/Ce, /sup 141/Pr, and /sup 139/La relative to /sup 140/Ce were obtained. The /sup 140/Ce data have a precision of 1 to 3% and the ratios are obtained with a precision of about 0.3%. To analyze these total cross section data a computer code was developed to calculate the total elastic, reaction, and differential elastic scattering cross sections for a neutron interacting with a nucleus. The interaction is represented by a spherically symmetric complex potential that includes spin-orbit coupling. The parameters of this potential were adjusted to approximate the /sup 140/Ce total cross over the energy range from 2.5 to 60 MeV. The energy dependence …
Date: May 8, 1980
Creator: Phillips, T.W.; Camarda, H.S. & White, R.M.
Object Type: Article
System: The UNT Digital Library
Backgrounds to the detection of two-body hadronic B decays (open access)

Backgrounds to the detection of two-body hadronic B decays

We consider backgrounds to the detection of the two-body hadronic decay modes of neutral B mesons and baryons. The largest background is due to the correlated production of pairs of high-p/sub T/ hadrons in the target, but this can be adequately rejected provided the experimental apparatus has sufficient resolution in mass and decay vertex. Another possible source of background arises from the production and decay of charmed and strange particles. Since these particles can travel considerable distances before decaying, they can give rise to backgrounds which may not be rejectable by means of vertex cut. We have simulated several backgrounds from charm, and we find them to be small compared to the expected level of signal. 8 refs., 1 fig., 2 tabs
Date: January 8, 1988
Creator: Kaplan, D. M.; Peng, Jen-Chieh; Abrams, G. S. & Stockdale, I. E.
Object Type: Article
System: The UNT Digital Library
Equipment qualification research program: program plan (open access)

Equipment qualification research program: program plan

The Lawrence Livermore National Laboratory (LLNL) under the sponsorship of the US Nuclear Regulatory Commission (NRC) has developed this program plan for research in equipment qualification (EQA). In this report the research program which will be executed in accordance with this plan will be referred to as the Equipment Qualification Research Program (EQRP). Covered are electrical and mechanical equipment under the conditions described in the OBJECTIVE section of this report. The EQRP has two phases; Phase I is primarily to produce early results and to develop information for Phase II. Phase I will last 18 months and consists of six projects. The first project is program management. The second project is responsible for in-depth evaluation and review of EQ issues and EQ processes. The third project is responsible for detailed planning to initiate Phase II. The remaining three projects address specific equipment; i.e., valves, electrical equipment, and a pump.
Date: June 8, 1982
Creator: Dong, R.G. & Smith, P.D.
Object Type: Report
System: The UNT Digital Library
Present capabilities and new developments in antenna modeling with the numerical electromagnetics code NEC (open access)

Present capabilities and new developments in antenna modeling with the numerical electromagnetics code NEC

Computer modeling of antennas, since its start in the late 1960's, has become a powerful and widely used tool for antenna design. Computer codes have been developed based on the Method-of-Moments, Geometrical Theory of Diffraction, or integration of Maxwell's equations. Of such tools, the Numerical Electromagnetics Code-Method of Moments (NEC) has become one of the most widely used codes for modeling resonant sized antennas. There are several reasons for this including the systematic updating and extension of its capabilities, extensive user-oriented documentation and accessibility of its developers for user assistance. The result is that there are estimated to be several hundred users of various versions of NEC world wide. 23 refs., 10 figs.
Date: April 8, 1988
Creator: Burke, G. J.
Object Type: Article
System: The UNT Digital Library
Total pion cross section measurements. Annual progress report, January 1, 1979-December 31, 1979 (open access)

Total pion cross section measurements. Annual progress report, January 1, 1979-December 31, 1979

The principal effort has been devoted to the data analysis for the pion-nucleus total cross section experiment. Forward scattering amplitudes have been obtained for ..pi..+- mesons on Al, /sup 40/Ca, Cu, Sn, Ho, and Pb. These results are given. Work is continuing on the data reduction for the remaining targets.
Date: February 8, 1980
Creator: Jakobson, M. J. & Jeppesen, R. H.
Object Type: Report
System: The UNT Digital Library
Laboratory procedures used in the hot corrosion project (open access)

Laboratory procedures used in the hot corrosion project

The objective of the Hot Corrosion Project in the LLNL Metals and Ceramics Division is to study the physical and chemical mechanisms of corrosion of nickel, iron, and some of their alloys when these metals are subjected to oxidizing or sulfidizing environments at temperatures between 850 and 950/sup 0/C. To obtain meaningful data in this study, we must rigidly control many parameters. Parameters are discussed and the methods chosen to control them in this laboratory. Some of the mechanics and manipulative procedures that are specifically related to data access and repeatability are covered. The method of recording and processing the data from each experiment using an LS-11 minicomputer are described. The analytical procedures used to evaluate the specimens after the corrosion tests are enumerated and discussed.
Date: April 8, 1980
Creator: Jeys, T.R.
Object Type: Report
System: The UNT Digital Library
Fast transient digitizer (open access)

Fast transient digitizer

Method and apparatus are presented for sequentially scanning a plurality of target elements with an electron scanning beam modulated in accordance with variations in a high-frequency analog signal to provide discrete analog signal samples representative of successive portions of the analog signal; coupling the discrete analog signal samples from each of the target elements to a different one of a plurality of high speed storage devices; converting the discrete analog signal samples to equivalent digital signals; and storing the digital signals in a digital memory unit for subsequent measurement or display.
Date: July 8, 1981
Creator: Villa, F.
Object Type: Patent
System: The UNT Digital Library
EPFL (Swiss) fusion-fission hybrid experiment. Progress report, November 1, 1981-January 31, 1982 (open access)

EPFL (Swiss) fusion-fission hybrid experiment. Progress report, November 1, 1981-January 31, 1982

The trip provided an opportunity for extensive discussions with the staff of the Institut de Genie Atomique (IGA) of the Ecole Polytechnique Federale de Lausanne (EPFL). The discussions covered both the planning of the first series of experiments to be performed in the Hybrid Experiment (hereafter referred to as LOTUS) and the status of calculational work being performed at the University of Washington in support of the LOTUS project.
Date: February 8, 1982
Creator: Woodruff, G.L.
Object Type: Report
System: The UNT Digital Library
Calibration of a neutron log in partially saturated media IV: effects of sonde-wall gap (open access)

Calibration of a neutron log in partially saturated media IV: effects of sonde-wall gap

A gap between a neutron sonde and the wall of a borehole can have a significant effect on the observed count rate. This effect was determined experimentally to be linear with gaps as large as 2.5 cm. The count rate is given by N/sub N/ = K/sub 0/ + K/sub 1/g where K/sub 0/ is the count rate that would be observed at zero gap, and g is the gap. The parameters K/sub 0/ and K/sub 1/ are dependent on both water (ie. hydrogen) content and bulk density. In many situations failure to correct the count rate for this gap effect can result in a significant degradation in the accuracy of the water content calculated from the count rate. In a dry borehole, K/sub 1/ is small at zero formation water content, and increases with formation water content. In a water-filled borehole, K/sub 1/ is large at zero formation water content, and tends to decrease with increasing formation water content, becoming zero, as of course it must, if the formation is pure water. The absolute value of K/sub 1/ increases with increasing density. A representation was determined for K/sub 0/ and K/sub 1/ from experimental data. This representation can be …
Date: March 8, 1984
Creator: Axelrod, M. C. & Hearst, J. R.
Object Type: Article
System: The UNT Digital Library
[Letter from James R. Miller to Carl L. Yeckel, October 8, 1987] (open access)

[Letter from James R. Miller to Carl L. Yeckel, October 8, 1987]

Letter from James R. Miller to Carl L. Yeckel, of the Carl B. and Florence E. King Foundation, on October 8, 1987, mentioning the recent visit of Julian C. Stanley to the university, and thanking Yeckel for his consideration of their proposal. Stanley's letter of thanks to Alfred Hurley is included.
Date: October 8, 1987
Creator: Miller, James R.
Object Type: Letter
System: The UNT Digital Library
[Letter from Valleau Wilkie, Jr. to James J. Muro, October 8, 1987] (open access)

[Letter from Valleau Wilkie, Jr. to James J. Muro, October 8, 1987]

Letter from Valleau Wilkie, Jr. to James J. Muro, on October 8, 1987, informing him that Muro's request for a grant to North Texas State University for the Texas Academy of Mathematics and Science has been denied, although he promises that it will be revisited in early 1988.
Date: October 8, 1987
Creator: Wilkie, Valleau, Jr.
Object Type: Letter
System: The UNT Digital Library