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Best Match Title Creator Date Created (Newest) Date Created (Oldest) Date Added (Newest) Date Added (Oldest)
Multiperipheral ring dynamics and a definition of the complete twisted Reggeon loop. [Diagonalization, naturality, threshold behavior, Regge cuts, complex helicity] (open access)

Multiperipheral ring dynamics and a definition of the complete twisted Reggeon loop. [Diagonalization, naturality, threshold behavior, Regge cuts, complex helicity]

The t less than 0 multiperipheral formalism of Ciafaloni, DeTar, Misheloff, Mueller, Muzinich and Yesian is reviewed, extended, and applied to the ordered S-matrix whose ring amplitudes comprise the zeroth level of the topological expansion. Toller M-function notation is used throughout. The bootstrap and cylinder problems are formulated in terms of a well defined helicity pole propagator; a definition of the complete twisted Reggeon loop, which appears in the one-twist term of the cylinder, is given as a helicity pole expansion. Some consideration is given to the following subjects: diagonalization, naturality, threshold behavior, Regge cuts, and complex helicity.
Date: November 1, 1977
Creator: Lucht, P.H.
Object Type: Report
System: The UNT Digital Library
Radio chemistry as a diagnostic in laser fusion experiments (open access)

Radio chemistry as a diagnostic in laser fusion experiments

Nuclear chemistry techniques have been employed in an attempt to measure the density of high compression laser fusion targets. Radioactive /sup 28/Al atoms formed in the /sup 28/Si(n,p)/sup 28/Al reaction arising from the interaction of the 14 MeV neutrons with the silicon atoms in the glass microsphere have been counted at Lawrence Livermore Laboratory using a ..beta..-..gamma.. coincidence method. The detection system that is employed allows activities corresponding to 100 aluminum atoms to be measured. From the observed number of activated atoms, neutron yields, and code calculations, information on the density of the compressed fuel can be obtained. This method is particularly valuable when the target compression becomes great enough to prohibit previously employed diagnostic techniques to be used. In addition, technique which utilizes a radioactive tracer to measure the isotropy of the target debris blowoff will also be discussed.
Date: November 1, 1977
Creator: Campbell, E.M.; Hicks, H.G.; Mead, W.C.; Glaros, S.S.; Coleman, L.W. & Laird, W.B.
Object Type: Article
System: The UNT Digital Library
PROCESSES FOR RECOVERY OF URANIUM AND THORIUM FROM GRAPHITE-BASE FUEL ELEMENTS. PART II (open access)

PROCESSES FOR RECOVERY OF URANIUM AND THORIUM FROM GRAPHITE-BASE FUEL ELEMENTS. PART II

Laboratory-scale tests on methods for recovering uranium and thorium from graphite-base reactor fuel elements are reported. The 90% HNO/sub 3/ process, which involves simultaneous disintegration and leaching in 21 M HNO/sub 3/, is applicable to all fuel elenments which do not contain coated fuel particles. Leaching of irradiated (0.001% burnup) fuels containing 3 and 12% uranlum recovered approximates 99.3 and 99.9%, respectively, of the uranium in two 4-hr leaches with boiling acid. The graphite residue retained > 50% of the long-lived fission products. Three successive leaches of fuel containing uranium and thorium recovered approximates 99% of both elements. Uranium recoveries by combustion in oxygen followed by dissolution of the ash hn nitric acid or fluorlde-catalyzed nitric acid are quantitative only when the fuel is not coated, does not contain Al/sub 2/O/sub 3/-coated fuel particles, and is free from impurities such as iron. During combustion up to 95% of the Ru-106 was volatilized from irradiated specimens. Recoveries, by leaching with 70% HNO/sub 3/, from fuel specimens containing Al/sub 2/O/sub 3/-coated fuel particles were greater than 99% when the specimens were ground finer than 200 mesh to ensure crushing of the fuel particles. (auth)
Date: November 30, 1961
Creator: Ferris, L.M.; Kibbey, A.H. & Bradley, M.J.
Object Type: Report
System: The UNT Digital Library
Evaluation of Wire Scanner for SM-1 (open access)

Evaluation of Wire Scanner for SM-1

Preliminary design concepts are presented for a wire scanner for experimentally evaluating spatial variations of neutron flux in the SM-l reactor core. Results of a literature search and determination of optimum criteria for flux mapping the core in minimum time dictated requirements for design concepts and specifications. The utility of both manually instrumented and automatically instrumented wire scanners was analyzed with respect to rapidity of measurement, selectivity of detector location, cost, value of data, plant downtime, and additional factors. (auth)
Date: November 22, 1961
Creator: Kemp, S. N.
Object Type: Report
System: The UNT Digital Library
CONCEPTUAL DESIGN AND ECONOMIC EVALUATION OF A STEAM-COOLED FAST BREEDER REACTOR (open access)

CONCEPTUAL DESIGN AND ECONOMIC EVALUATION OF A STEAM-COOLED FAST BREEDER REACTOR

A conceptual design and economic evaluation of 300 and 40 MW/.sub e/ steam-cooled fast breeder reactor power plants were performed. A reactor core composed of U-Pu oxide rod-type fuel elements clad with Inconel-X and surrounded by a blanket of depleted UO/sub 2/ fuel was studied in some detail. Reactor breeding ratios of from 1.27 to 1.5 and overall system doubling times of from 20 to 30 years are achievable. For the near term (1967) 300 MW/sub e/ plant, an energy cost of 7.6 mills/kwh is estimated, based on AEC ground rules for privately financed plants and utilities. This cost may go down to 5.7 mills/kwh by 1975. For the 40 MW/sub e/ plant corresponding energy costs are 19.5 and 13.7 mills/kwh, r -spectively. The R&D program required for this reactor concept is estimated at million with an additional million for improvements leading to the 1975 reactor. Investigation of the operational and safety aspects of the reactor indicated that satisfactory procedures can be used for startup, shutdown, and emergency cooling of the reactor. An increase in reactivity upon flooding can be prevented by incorprating small amounts of high resonance absorption material in the core. Preliminary calculations indicate a substantial increase in …
Date: November 15, 1961
Creator: Sofer, G.; Hankel, R.; Goldstein, L. & Birman, G.
Object Type: Report
System: The UNT Digital Library
Studies on transition metals and alloy Fischer-Tropsch catalysts, their electronic and bulk properties. (I: Fe/MnO; II: Fe/TiO/sub 2/; III: Fe/Mord. ). Final report, July 1, 1982-September 30, 1983 (open access)

Studies on transition metals and alloy Fischer-Tropsch catalysts, their electronic and bulk properties. (I: Fe/MnO; II: Fe/TiO/sub 2/; III: Fe/Mord. ). Final report, July 1, 1982-September 30, 1983

The objectives were: (1) to characterize samples D1, 10% FeO/90% MnO, and D2, 48% FeO/52% MnO, under varying conditions of reduction (at 250/sup 0/C or 350/sup 0/C in H/sub 2/) and of syngas reaction 1:1 of CO:H/sub 2/ at 290/sup 0/C) and in some cases use CO only for reduction and to identify species by Moessbauer Spectroscopy and Magnetization (sigma/sub s) measurement; (2) similarly, to see if there is any metal (oxide)/support (Mordenite) interaction by the same techniques. The characterization was carried out with above techniques and the kinetic results for syngas were obtained on the above systems mostly at PETC. During reduction of Fe-oxide/Mn-oxide an intermediate Mn-ferrite phase was detected. After reduction, species such as Fe/sup 0/+Fe/sup 3 +/+Fe/sup 2 +/ in varying total proportions (45% at 290/sup 0/C and Fe/sup 0/+Fe/sup 2 +/ 75% were found at 350/sup 0/C). Syngas conversion showed Fe-carbides (Fe/sub 2/C/sub 2/+Fe/sub 3/C) depending on the reaction conditions, and the composition of D/sub 1/ and D/sub 2/. With the fresh ..gamma..-Fe/sub 2/O/sub 3/ (identified by Moessbauer) on Mordenites with varying ratios of SiO/sub 2//Al/sub 2/O/sub 3/, a decrease in (sigma/sub s/) was found with lowering of the ratios from 60 to 17. At 17% …
Date: November 1, 1983
Creator: Mulay, L.N.
Object Type: Report
System: The UNT Digital Library
Improved ceramic heat exchanger material (open access)

Improved ceramic heat exchanger material

Various ceramic materials in the form of small, monolithic bars were screened as candidate materials in heat exchanger structures for automotive gas turbine engines. The material finally selected consists of 60 w/o* petalite (LAS) and 40 w/o of a recrystallizable glass which converts during thermal processing to cordierite (MAS). This new material, GE-3200, was fabricated by Coors Porcelain Company into a circular honeycomb structure 53.3 cm diameter and 10.2 cm thick (21'' x 4'') and having 69.8 holes/cm/sup 2/ (450 holes/in./sup 2/) of rectangular geometry. Dimensions of each cell are about 2.5 mm x 0.5 mm (0.1'' x 0.02'') with wall thicknesses about 0.20 mm (0.008''). Small bar-shaped specimens of the honeycomb were used to measure thermal, chemical, and mechanical properties and for macro- and microstructure examination. Cylindrical honeycomb specimens about 15.2 cm diameter and 10.2 in. thick (6'' x 4'') were sent to Ford Motor Company and are currently being tested in a gas turbine engine. Data obtained from testing the bar-shaped honeycomb specimens of GE-3200 and from testing bar-shaped honeycomb specimens of Corning 9455 were compared. Results indicate that GE-3200 has significantly better resistance to sulfuric acid and to sodium chloride than Corning 9455; thermal expansion of GE-3200 …
Date: November 1, 1977
Creator: Rauch, H. W., Sr.
Object Type: Report
System: The UNT Digital Library
Titanium/gold process characterization (open access)

Titanium/gold process characterization

Characterization of the titanium/gold (Ti/Au) deposition process used at the Allied-Signal Inc., Albuquerque Microelectronics Operation (AMO) was performed. Tests were conducted to set up evaporation parameters, correlate titanium and gold thicknesses to sheet resistance, improve thickness uniformity, and reduce frontside contamination of deposit material on product wafers. The Ti/Au process is the final step in the production of integrated circuits (ICs) at the AMO wafer fabrication facility. 3 figs.
Date: November 1, 1991
Creator: Fajardo, L.S.
Object Type: Report
System: The UNT Digital Library
CASTING OF LONG AND THIN PLATES OF URANIUM-MOLYBDENUM ALLOYS (open access)

CASTING OF LONG AND THIN PLATES OF URANIUM-MOLYBDENUM ALLOYS

The development of procedures for the vacuum induction casting of U--Mo alloys into both thin (0.010 to 0.100-in. thick) plates and long (36 in.) plates is described. Melting and casting cycles were developed, and casting techniques established, which resulted in sound, integral plates. These plates were evaluated by radiographic and metallographic examination, and by chemical analysis. The results indicated the feasibility of the process for the fabrication of fuel plates for nuclear reactors. The process promises a potential reduction in fabrication costs, by eliminating waste. (auth)
Date: November 1, 1961
Creator: Katz, N.H. & Binstock, M.H.
Object Type: Report
System: The UNT Digital Library
STUDIES OF THE SCINTILLATION PROCESS IN CsI(Tl) (open access)

STUDIES OF THE SCINTILLATION PROCESS IN CsI(Tl)

The scintillation response of CsI(Tl) crystals, having various thallium contents, was measured for excitation of the crystals by monoenergetic gamma rays, protons, and alpha particles. The investi gation was made to provide a test of some of the features of a theoretical model of the scintillation process in thallium-activated alkali iodides proposed by Murray and Meyer. In order to insure that the results obtained in this program would provide a critical test of the scintillation model, special attention was paid to technical effects which could influence the interpretation of the experimental data. For example, the effect of the pulseanalysis time on the relative scintillation response of CsI(Tl) to various charged parti cles was investigated. In addition, the emission spectra of the CsI(Tl) crystals were measured for excitation by x rays, protons, and alpha particles. The results of the investigation showed that the scintillation efficiency of CsI(Tl) is a continuous function of dE/dx, as assumed in the scintillation model, within the accuracy of the experiments when the effect of delta ravs are considered. This led to the conclusion that the light output of CsI(Tl) crystals is, in general, a nonlinear function of the energy of the particle. The shape of the …
Date: November 30, 1962
Creator: Gwin, R. & Murray, R. B.
Object Type: Report
System: The UNT Digital Library
Secondary defects in quenched platinum (open access)

Secondary defects in quenched platinum

The structure of secondary defects in two different platinum purities quenched under ultra high vacuum, has been studied by transmission electron microscopy. Faulted loops on (100) planes have been observed in both materials. In the less pure platinum, Pt B (but purer in terms of carbon content), the defects were observed after quenching, whereas in the purest one, Pt A (but less pure in terms of carbon content), the defects were formed after a long annealing. The Burgers vector of the loops formed after the quenching was a/3 <100> and for loops formed during long annealings, was a/2 <100>, apparently. It was found that in Pt B the loop density increased and the loop size decreased as the quenching temperature was lowered.The same effect was produced by increasing the carbon content by a small amount. The loop formation was totally inhibited by adding a larger amount of carbon and also when the quenching was performed in poor vacuum (approx. 0.01 torr) or in air. The defects can be interpreted as pure vacancy loops heterogeneously nucleated at carbon atom clusters or, as plate like precipitates of carbon atoms and vacancies formed by a co-precipitation mechanism. The discussion of the experimental results …
Date: November 1, 1979
Creator: Perez, M.I.
Object Type: Report
System: The UNT Digital Library
Hot-gas cleanup system model development. Volume I. Final report (open access)

Hot-gas cleanup system model development. Volume I. Final report

This two-volume report summarizes the state of the art in performance modeling of advanced high-temperature, high-pressure (HTHP) gas cleanup devices. Volume I contains the culmination of the research effort carried over the past 12 months and is a summary of research achievements. Volume II is the user's manual for the computer programs developed under the present research project. In this volume, Section 2 presents background information on pressurized, fluidized-bed combustion concepts, a description of the role of the advanced gas cleanup systems, and a list of advanced gas cleanup systems that are currently in development under DOE sponsorship. Section 3 describes the methodology for the software architecture that forms the basis of the well-disciplined and structured computer programs developed under the present project. Section 4 reviews the fundamental theories that are important in analyzing the cleanup performance of HTHP gas filters. Section 5 discusses the effect of alkali agents in HTHP gas cleanup. Section 6 evaluates the advanced HTHP gas cleanup models based on their mathematical integrity, availability of supporting data, and the likelihood of commercialization. As a result of the evaluation procedure detailed in Section 6, five performance models were chosen to be incorporated into the overall system simulation …
Date: November 1, 1982
Creator: Ushimaru, K.; Bennett, A. & Bekowies, P.J.
Object Type: Report
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
The Thermodynamic Properties of the Alkali Halides (open access)

The Thermodynamic Properties of the Alkali Halides

The thermodynamic properties of the alkali halides are reviewed, presenting data supplementary to that of Brewer and Brackett, Chem. Rev. 61: 425-432(1961). (T.R.H.)
Date: November 1961
Creator: Brewer, L.
Object Type: Report
System: The UNT Digital Library
Coal fracture measurements using in situ electrical methods: preliminary results (open access)

Coal fracture measurements using in situ electrical methods: preliminary results

None
Date: November 20, 1974
Creator: Lytle, R.J.; Laine, E.F. & Lager, D.L.
Object Type: Report
System: The UNT Digital Library
System for evaluating the deformation of various materials under compressive loads (open access)

System for evaluating the deformation of various materials under compressive loads

None
Date: November 1, 1975
Creator: Gallman, R. A.
Object Type: Report
System: The UNT Digital Library
Development of mild gasification process (open access)

Development of mild gasification process

Under a previous contract with Morgantown Energy Technology Center (METC), Department of Energy (DOE) Contract No. AC21-84MC21108, UCC Research Corporation (UCCRC) built and tested a 1500 lb/day Mild Gasification Process Development Unit (MGU). The MGU, as tested under the previous contract, is shown in Figure 1. Testing completed under the previous contract showed that good quality hydrocarbon liquids and good quality char can be produced in the MGU. However, the MGU is not optimized. The primary objectives of the current project are to optimize the MGU and determine the suitability of char for several commercial applications. The program consists of four tasks; Task 1 -- Test Plan; Task 2 -- Optimization of Mild Gasification Process; Task 3 -- Evaluation of Char and Char/Coal Blends as a Boiler/Blast Furnace Fuel; and Task 4 -- Analysis of Data and Preparation of Final Report. Task 1 has been completed while work continued on Task 2.
Date: November 1, 1987
Creator: Chu, C.I.C. & Gillespie, B.L.
Object Type: Report
System: The UNT Digital Library
Design of a water jet drill for development of geothermal resources. Progress report, October 1--November 30, 1977 (open access)

Design of a water jet drill for development of geothermal resources. Progress report, October 1--November 30, 1977

Progress is reported in the evaluation of the performance of a water jet drill in a stressed rock, particularly in drilling at hole diameters in excess of one inch. Drilling tests are being carried out in a barrier pillar in a layer of coarse, lead-bearing sandstone. Problems encountered in the test drilling are discussed. (JGB)
Date: November 30, 1977
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Islets of stability beyond period doubling (open access)

Islets of stability beyond period doubling

Period doubling of a periodic orbit of an area preserving map appears to lead to the elimination of all closed invariant curves in the vicinity. We show, however, that there are always islets of stabilhty again beyond the accumulation point of the period doubling sequence.
Date: November 1, 1981
Creator: Mackay, R.S.
Object Type: Report
System: The UNT Digital Library
Central receiver solar thermal power system, Phase 1. CDRL Item 2. Pilot plant preliminary design report. Volume IV. Receiver subsystem. [10-MW Pilot Plant and 100-MW Commercial Plant] (open access)

Central receiver solar thermal power system, Phase 1. CDRL Item 2. Pilot plant preliminary design report. Volume IV. Receiver subsystem. [10-MW Pilot Plant and 100-MW Commercial Plant]

The conception, design, and testing of the receiver subsystem proposed by the McDonnell Douglas/Rocketdyne Receiver team for the DOE 10-MW Pilot Plant and the 100-MW Commercial Plant are described. The receiver subsystem consists of the receiver unit, the tower on which the receiver unit is mounted above the collector field, and the supporting control and instrumentation equipment. The plans for implementation of the Pilot Plant are given including the anticipated schedule and production plan (procurement, installation, checkout, and maintenance). Specifications for the performance, design, and test requirements for the Pilot Plant receiver subsystem are included. (WHK)
Date: November 1, 1977
Creator: Hallet, Jr., R. W. & Gervais, R. L.
Object Type: Report
System: The UNT Digital Library
Phase-change thermal energy storage: Final subcontract report (open access)

Phase-change thermal energy storage: Final subcontract report

The research and development described in this document was conducted within the US Department of Energy's Solar Thermal Technology Program. The goal of this program is to advance the engineering and scientific understanding of solar thermal technology and to establish the technology base from which private industry can develop solar thermal power production options for introduction into the competitive energy market. Solar thermal technology concentrates the solar flux using tracking mirrors or lenses onto a receiver where the solar energy is absorbed as heat and converted into electricity or incorporated into products as process heat. The two primary solar thermal technologies, central receivers and distributed receivers, employ various point and line-focus optics to concentrate sunlight. Current central receiver systems use fields of heliostats (two-axes tracking mirrors) to focus the sun's radiant energy onto a single, tower-mounted receiver. Point focus concentrators up to 17 meters in diameter track the sun in two axes and use parabolic dish mirrors or Fresnel lenses to focus radiant energy onto a receiver. Troughs and bowls are line-focus tracking reflectors that concentrate sunlight onto receiver tubes along their focal lines. Concentrating collector modules can be used alone or in a multimodule system. The concentrated radiant energy …
Date: November 1, 1989
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Sodium compatibility of HT-9 and Fe-9Cr-1Mo steels (open access)

Sodium compatibility of HT-9 and Fe-9Cr-1Mo steels

Ferritic steels have been receiving significant attention for possible use as steam generator tubing, and as alternate structural materials for liquid-metal heat-transport systems in commercial fast reactors, fusion reactors, etc. The materials are chosen on the basis of their high thermal conductivity, resistance to stress-corrosion-cracking in aqueous and steam environments, favorable fabricability and fairly low cost. These steels are available in several classes based on the microstructure and alloy content, viz., martensitics, bainitics, delta ferritics, and duplex steels. The low alloy bainitic steels (Fe-2-1/4Cr-1Mo) undergo extensive decarburization when exposed to high temperature flowing sodium. It is for this reason that ferritic steels with higher chromium (9 to 12% Cr) content have been proposed to minimize the carbon transfer and eventual degradation of mechanical properties. The martensitic steels, HT-9 and improved Fe9Cr1Mo are being considered as cladding/duct materials for liquid metal reactors (LMR). The alloy HT-9 is based on 12Cr1Mo composition. The improved Fe9Cr1Mo alloy is based on 9Cr1Mo composition as its name implies. The objective of the work reported here is to evaluate the sodium compatibility of the alloys at temperatures and flow rates typical of LMR cores. Testing was done for 8104 hours at 60/sup 0/C and 3992 hours …
Date: November 1, 1985
Creator: Anantatmula, R. P. & Brehm, W. F.
Object Type: Article
System: The UNT Digital Library
VUV (vacuum ultraviolet) laser diagnostics of H sup - ion sources (open access)

VUV (vacuum ultraviolet) laser diagnostics of H sup - ion sources

Vacuum ultraviolet laser absorption spectroscopy has been employed to measure the populations and temperatures of ground electronic state H-atoms and vibrationally-excited H{sub 2} molecules in a volume H{sup -} ion source. Measurements of both species have been made under a variety of discharge conditions. Vibrational levels to v{double prime}=8 have been measured, with the vibrational population distribution well described by a temperature of 4150K. 10 refs., 9 figs.
Date: November 1, 1989
Creator: Young, A. T.; Stutzin, G. C.; Leung, K. N. & Kunkel, W. B.
Object Type: Article
System: The UNT Digital Library
Proceedings of a conference on solar energy for heating greenhouses and greenhouse-residential combinations (open access)

Proceedings of a conference on solar energy for heating greenhouses and greenhouse-residential combinations

Seventeen papers are included. A separate abstract was prepared for each for Energy Research Abstracts (ERA); eight are included in Energy Abstracts for Policy Analysis (EAPA). (MHR)
Date: November 1, 1977
Creator: Bond, T E; Godbey, L C & Zornig, H F
Object Type: Article
System: The UNT Digital Library