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92,498 Matching Results

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(open access)

Universal formula for the quasistatic second-order density perturbation by a cold magnetoplasma wave

Using the general expression for the ponderomotive Hamiltonian, the quasi-static quasi-neutral density change caused by the ponderomotive force of a cold magnetoplasma wave of arbitrary frequency and polarization is obtained. This formula agrees with and extends previous results for unmagnetized and magnetized plasma.

Date: December 16, 1977

Creator: Kaufman, A. N.; Cary, J. R. & Pereira, N. R.

Object Type: Article

System: The UNT Digital Library

(open access)

Tests of Bearing Materials for the Experimental Through-Tubes in the Egcr

The four experimental through-tubes provided in the Experimental Gas Cooled Reactor will extend directly through the core of the reactor and penetrate both the upper and lower pressure vessel heads. Each tube is anchored in an upper head nozzle and the bottom end is allowed to slide in a lower head nozzle. This lower nozzle is basically a T'' section that provides bottom access to the through-tube and a side access for the piping which connects the throughtube to the experimenter's cell. Due to differential thermal expansion of the through- tubes relative to the reactor pressure vessel, vertical movement of the through- tube within the T'' section will be experienced. At the same time a horizontal thrust applied to each tube by thermal expansion of the piping to the experimental cell will result in metalto-metal contact between each tube and the lower T'' section. Tests were conducted on three types of bearing material proposed for use on the through-tubes and T'' sections to minimize galling which can be expected to occur. Stellite No. 12 has been demonstrated to be an adequate bearing material for the intended application. (auth)

Date: July 16, 1962

Creator: MacPherson, R. E. & Smith, A. M.

Object Type: Report

System: The UNT Digital Library

(open access)

RODCON: a finite difference heat conduction computer code in cylindrical coordinates

RODCON, a finite difference computer code, was developed to calculate the internal temperature distribution of the fuel rod simulator (FRS) for the Core Flow Test Loop (CFTL). RODCON solves the implicit, time-dependent forward-differencing heat transfer equation in 2-dimensional (Rtheta) cylindrical coordinates at an axial plane with user specified radial material zones and surface conditions at the FRS periphery. Symmetry of the boundary conditions of coolant bulk temperatures and film coefficients at the FRS periphery is not necessary.

Date: September 16, 1980

Creator: Conklin, J. C.

Object Type: Article

System: The UNT Digital Library

(open access)

GAS-COOLED REACTOR PROGRAM QUARTERLY PROGRESS REPORT FOR PERIOD ENDING MARCH 31, 1962

Progress on the gas-cooled reactor program is reported. Separate abstracts were prepared for each of the 14 sections. (M.C.G.)

Date: July 16, 1962

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

A System for Generating Gamma Ray Cross Section Data for Use with the IBM-7090 Computer

A system for generating detailed tables of gamma ray cross section data has been devised for use on the IBM7090 computer. This sy;tem obviates the preparation of large amounts of cross section data. It also provides a scheme for rapid access to these tabulated values. (auth)

Date: May 16, 1962

Creator: Penny, S. K.; Emmett, M. B. & Trubey, D. K.

Object Type: Report

System: The UNT Digital Library

(open access)

Comments on muon trapping. [HALO computer code]

Muons that result from the collisions of protons in the ISABELLE beams with other nucleons introduce important background or signal for experiments. Their ability to pass through the conductors and steel of ISABELLE magnets results in complicated trajectories. Some oscillate about quasistable orbits and are called ''trapped.'' A number of typical trajectories were plotted, and flux estimates were made with a Monte Carlo program, HALO. Trapping tends to reduce shielding requirements somewhat, but the effect does not appear to be a very large one from these initial investigations. More aspects need to be studied, and HALO appears to be a useful tool for doing so.

Date: June 16, 1977

Creator: Stevens, A. J. & Thorndike, A. M.

Object Type: Report

System: The UNT Digital Library

(open access)

Probing the possibility of a /sup 12/C/sup 13/C abundance gradient from observations of interstellar CH/sup +/

I have performed high signal-to-noise (SN /equals/ 300 to 500) observations of interstellar CH/sup /plus// at Lick Observatory and at CTIO of the reddened, early-type stars HD 183143, HD 24432, and HD 157038 in an effort to probe the existence of a /sup 12/C/sup 13/C abundance gradient in our Galaxy.

Date: September 16, 1987

Creator: Hawkins, I.

Object Type: Article

System: The UNT Digital Library

(open access)

Recommended new criteria for the selection of nuclear waste repository sites in Columbia River basalt and US Gulf Coast domed salt

Screening criteria and specifications are recommended to aid in the evaluation of sites proposed for nuclear waste disposal in basalt and domed salt. The recommended new criteria proposed in this report are intended to supplement existing repository-related criteria for nuclear waste disposal. The existing criteria are contained in 10 CFR 60 sections which define siting criteria of the Nuclear Regulatory Commission (NRC), and ONWI 33(2) which defines siting criteria of the Office of Nuclear Waste Isolation (ONWI) for the Department of Energy. The specifications are conditions or parameter values that the authors recommend be applied in site acceptance evaluations. The siting concerns covered in this report include repository depth, host rock extent, seismic setting, structural and tectonic conditions, groundwater and rock geochemistry, volcanism, surface and subsurface hydrology, and socioeconomic issues, such as natural resources, land use, and population distribution.

Date: June 16, 1980

Creator: Steinborn, T.L.; Wagoner, J.L.; Qualheim, B.; Fitts, C.R.; Stetkar, R.E. & Turnbull, R.W.

Object Type: Report

System: The UNT Digital Library

(open access)

Small Angle Physics at CDF: A Progress Report

In 1989 CDF collected data in special high beta runs with a trigger selecting elastic and inelastic events in order to measure the total cross section ({sigma}{sub tot}) and the differential elastic cross section (d{sigma}{sub el}/dt). Data were taken at cms energies of 300, 540, 1000 and 1800 GeV. A double arm magnetic spectrometer located along the beam pipe tags the particles scattered at very small angles and tracking detectors surrounding the interaction point reveal particles produced at larger angles. We discuss the status of the analysis of elastic and inelastic events with emphasis on the event selection and the background subtraction. 5 refs., 14 figs., 3 tabs.

Date: December 16, 1989

Creator: Paoletti, Riccardo

Object Type: Article

System: The UNT Digital Library

(open access)

Hydrogenation of CO and CO/sub 2/ on clean rhodium and iron foils. Correlations of reactivities and surface compositions

An experimental arrangement consisting of an ultrahigh vacuum bell jar equipped with an internal sample isolation cell was used to investigate the hydrogenation of CO over Fe and Rh surfaces. This apparatus permitted both UHV surface characterization (Auger electron spectroscopy, low-energy electron diffraction) and high pressure (1-20 atm) catalytic reactions to be carried out. Small surface area (approximately 1 cm/sup 2/) metal samples, both single crystals and polycrystalline foils, were used to catalyze the H/sub 2//CO reaction at high pressures (1-6 atm). Reaction products were monitored with a gas chromatograph equipped with a flame ionization detector. The surface compositions of the metal samples were determined before and after the reaction and the results correlated with the observed product distributions and reaction rates. In addition, the influence of various surface additives (carbon, oxygen, potassium) was also investigated. Iron was the more reactive of the two metals studied and was found to produce C/sub 1/-C/sub 5/ straight chain hydrocarbons but it poisoned rapidly. The catalytically active surface of both metals was covered with a carbonaceous monolayer. The carbonaceous monolayer was stable on the rhodium surface and produced C/sub 1/-C/sub 4/ hydrocarbons at a steady rate even after several hours of reaction. The …

Date: December 16, 1977

Creator: Dwyer, D.; Yoshida, K. & Somorjai, G.A.

Object Type: Article

System: The UNT Digital Library

(open access)

Ordered S-matrix approach to the topological expansion for baryons and mesons. [Ordered Hilbert space, Reggeon closed loops]

A proposal is made for extending to processes involving baryons the ordered Hilbert space approach to the topological expansion. The proposal is based on a topological classification scheme for baryonic processes that is similar to one used previously for the lowest-order contributions, but is in terms of the minimum number of reggeon closed loops instead of handles.

Date: August 16, 1977

Creator: Stapp, Henry P.

Object Type: Report

System: The UNT Digital Library

(open access)

Simulation of the carbon cycle in the ocean

A dual carbon-nitrogen biological model of the upper ocean has been developed, which has successfully allowed predictions of fluxes of carbon between atmosphere and the deep ocean to made. Regarding studying the carbon cycle in the ocean, the modelling has highlighted the need for a good understanding of the interactions between the carbon and nitrogen cycles, and also the importance of zooplankton grazing and levels of overwintering biological stocks. Problems have been encountered with the accuracy of prediction of the partial pressure of carbon dioxide in the surface ocean, and the sensitivity of the model to zooplankton parameters, and those parameters which effect overwintering stocks (e.g. mortality parameters). The model has recently been incorporated into a physical General Circulation Model of the Atlantic Ocean. Future work will involve assessing the performance of the biological model in General Circulation Models, and making necessary refinements in order to improve its predictive ability. 1 ref., 1 fig.

Date: September 16, 1991

Creator: Fasham, M.J.R.

Object Type: Report

System: The UNT Digital Library

(open access)

Secondary recovery of plutonium and americium from process waste streams by solvent extraction

A solvent extraction process is being evaluated for the secondary recovery of plutonium and americium from Rocky Flats waste streams. The bidentate organophosphorus compounds dihexyl-N,N-diethylcarbamylmethylene phosphonate and its dibutyl analogue have been shown to be selective extractants for the actinides from solutions of nitric acid. The results from laboratory test runs in which the organophosphorus extractants were used for processing secondary waste solutions will be presented. Solvent extractant properties and purification procedures are discussed.

Date: January 16, 1978

Creator: Hagan, P. G. & Navratil, J. D.

Object Type: Article

System: The UNT Digital Library

(open access)

Experimental and Analytical Reactivity Studies of Clean Critical Stainless Steel Cores

ABS>The results are presented of critical water height measurements made on close-packed lattices of Spert III, highly enriched, plate-type, stainless- steel-clad fuel elements. Experiments were conducted with cores containing no control rods and with cores containing a single, fully-inserted control rod. The "clean critical" data obtained in these experiments were used to test the validity of various aspects of a four-group, diffusion theory analysis of the full scale Spert III reactor. The results of the analyses of the rod-free and single-rodded critical lattices show that for such stainless steel cores k/sub eff/ can be calculated to within 1% DELTA k and that the Spert III control rod worth is calculable to a few tenths % DELTA k. (auth)

Date: June 16, 1961

Creator: Spano, A. H.

Object Type: Report

System: The UNT Digital Library

(open access)

Proposed method of assembly for the BCD silicon strip vertex detector modules

The BCD Silicon strip Vertex Detector is constructed of 10 identical central region modules and 18 similar forward region modules. This memo describes a method of assembling these modules from individual silicon wafers. Each wafer is fitted with associated front end electronics and cables and has been tested to insure that only good wafers reach the final assembly stage. 5 figs.

Date: October 16, 1989

Creator: Lindenmeyer, C.

Object Type: Report

System: The UNT Digital Library

(open access)

Enhancing the use of coals by gas reburning-sorbent injection

The objective of this project is to evaluate and demonstrate a cost effective emission control technology for acid rain precursors, oxides of nitrogen (NO{sub x}) and sulfur (SO{sub x}), on two coal fired utility boilers in Illinois. The units selected are representative of pre-NSPS design practices: tangential and cyclone fired. A third unit, wall fired, is on hold'' because of funding limitations. The specific objectives are to demonstrate reductions of 60 percent in NO{sub x} and 50 percent in SO{sub x} emissions, by a combination of two developed technologies, gas reburning (GR) and sorbent injection (SI). With GR, about 80--85 percent of the coal fuel is fired in the primary combustion zone. The balance of this fuel is added downstream as natural gas to create a slightly fuel rich environment in which NO{sub x} is converted to N{sub 2}. The combustion process is completed by overfire air addition. SO{sub x} emissions are reduced by injecting dry sorbents (usually calcium based) into the upper furnace. The sorbents trap SO{sub x} as solid sulfates that are collected in the particulate control device.

Date: April 16, 1990

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

Comparative analysis of internal fuel motion in annular fuel designs

In this paper, the whole-core reactivity consequences of internal fuel motion in three annular fuel designs during a hypothetical 3 dollars/s transient overpower (TOP) accident are compared to determine the effect of geometric design variations. The PINEX-2 and PINEX-3 experiments were performed in the TREAT reactor using annular fuel pins irradiated in GETR. This paper investigates three combinations of solid and annular axial blankets and fission gas plena: top annular blanket and plenum, bottom annular blanket and plenum, and both top and bottom (dual) annular blankets and plena. The dual plena design case showed a significant decrease in internal fuel motion over the single plenum design cases.

Date: September 16, 1983

Creator: Smith, D. E.

Object Type: Article

System: The UNT Digital Library

(open access)

Development of a solar-desiccant dehumidifier. Phase II second technical progress report

The solar desiccant air conditioner (SODAC) system and its operation are described, including the characteristics of the major components, the performance at design conditions, and the control schemes for optimum operation in various climates. The system uses granular silica gel as a desiccant. It may operate in either a recirculated mode (no air exchange between the outside and the conditioned space) or a ventilated mode (air exchanged between outside and conditioned space). The test data in the ventilated mode at design flow rates are presented. Data include outdoor and indoor inlet wet and dry bulb temperatures, indoor outlet dry and wet bulb temperatures, capacity, coefficient of performance, air flow rates, hot water temperature, and solar heat used. The effects of indoor, outdoor, and hot water temperatures on the capacity and coefficient of performance are shown graphically, and the recirculated and ventilated modes, performances are compared. (LEW)

Date: October 16, 1981

Creator: Rousseau, J.

Object Type: Report

System: The UNT Digital Library

(open access)

Unit Operations Section Monthly Progress Report, November 1961

Openation of a 6-in.-dia foam separation column with Sr/sup 89/ tracer and dodecylbenzenesulfonate as a surfactant and foaming agent was continued. The catalytic oxidation of H/sub 2/, CO, and CH/sub 4/ was studied using a nickel- chromepalladium ribbon catalyst. A Mark I prototype fuel assembly was sheared to within 1.5-in. of the end by modifying the gas hydraulic system of the shear. The force required to shear a highly carburized Mark I fuel assembly ductile tubing. Demonstration of the mechanical dejacketing of the SRE Core I fuel burned to approximates 675 Mwd/ton and cooled about 2 years is complete, and decontamination and equipment removal from the segmenting cell is approximately 90% complete. Ten SRE Core I fuel jackets were dissolved in aqua regia and analysis showed negligible U and Pu. A semicontinuous leach run, in which -2 mesh graphite fuel containing 2.6% U was leached in 90% HNO/sub 3/ at 60 deg C, gave only 0.37% U loss. Graphically estimated spectral factors for radiation between tubes within fuel bundles and improved wall radiation factors were rised to calculate the temperature distribution expected within spent fuel elements. Further studies of the dissolution of zirconium oxide by HF in fused salt resulted …

Date: May 16, 1962

Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.

Object Type: Report

System: The UNT Digital Library

(open access)

A fast neutron time of flight system for use with cyclotrons

A reference pulse generator, transistorized timedifference-to-pulse- height converter, and beam pulse scaler are described and discussed as to their function in the fast neutron time-of-flight system for use with cyclotrons, The system is used for angular distribution and cross section measurements. Results are presented showing time resolution, absolute counting efficiency, and beam pulse scaling of the system. (N.W.R.)

Date: August 16, 1962

Creator: Fulbright, H. W.; Verba, J. W.; Deshpande, V. K. & Hamann, A. K.

Object Type: Report

System: The UNT Digital Library