2,842 Matching Results

Search Results

Advanced search parameters have been applied.

Methods of Opacity Calculations

Description: "Methods for calculating the opacity of materials at high temperatures are discussed in this report. Minor improvements are outlined for the treatment of continuous absorption processes, and a small error usually made in treating the scattering process is corrected. In contrast to all previous calculations of opacity, the effect of line absorption is carefully examined, for it may well be the dominant process under certain conditions of temperature and density. Detailed methods for calculating the line absorption contribution are, therefore, developed. To illustrate the principles involved, the opacity of pure iron at a temperature of 1000 volts and normal density is worked out in detail" (p. ii).
Date: 1949
Creator: Mayer, Harris
Partner: UNT Libraries Government Documents Department

Ka-Band ARM Zenith Radar (KAZR) Instrument Handbook

Description: The Ka-band ARM zenith radar (KAZR) is a zenith-pointing Doppler cloud radar operating at approximately 35 GHz. The KAZR is an evolutionary follow-on radar to ARM's widely successful millimeter-wavelength cloud radar (MMCR). The main purpose of the KAZR is to provide vertical profiles of clouds by measuring the first three Doppler moments: reflectivity, radial Doppler velocity, and spectra width. At the sites where the dual-polarization measurements are made, the Doppler moments for the cross-polarization channel are also available. In addition to the moments, velocity spectra are also continuously recorded for each range gate.
Date: March 6, 2012
Creator: Widener, K; Bharadwaj, N & Johnson, K
Partner: UNT Libraries Government Documents Department

Doppler Lidar (DL) Handbook

Description: The Doppler lidar (DL) is an active remote sensing instrument that provides range- and time-resolved measurements of radial velocity and attenuated backscatter. The principle of operation is similar to radar in that pulses of energy are transmitted into the atmosphere; the energy scattered back to the transceiver is collected and measured as a time-resolved signal. From the time delay between each outgoing transmitted pulse and the backscattered signal, the distance to the scatterer is inferred. The radial or line-of-sight velocity of the scatterers is determined from the Doppler frequency shift of the backscattered radiation. The DL uses a heterodyne detection technique in which the return signal is mixed with a reference laser beam (i.e., local oscillator) of known frequency. An onboard signal processing computer then determines the Doppler frequency shift from the spectra of the heterodyne signal. The energy content of the Doppler spectra can also be used to determine attenuated backscatter.
Date: February 13, 2012
Creator: Newsom, RK
Partner: UNT Libraries Government Documents Department

STRUCTURE AND FUNCTION OF SUBSURFACE MICROBIAL COMMUNITIES AFFECTING RADIONUCLIDE TRANSPORT AND BIOIMMOBILIZATION

Description: The objectives of this project were to: (1) isolate and characterize novel anaerobic prokaryotes from subsurface environments exposed to high levels of mixed contaminants (U(VI), nitrate, sulfate), (2) elucidate the diversity and distribution of metabolically active metal- and nitrate-reducing prokaryotes in subsurface sediments, and (3) determine the biotic and abiotic mechanisms linking electron transport processes (nitrate, Fe(III), and sulfate reduction) to radionuclide reduction and immobilization. Mechanisms of electron transport and U(VI) transformation were examined under near in situ conditions in sediment microcosms and in field investigations at the Oak Ridge Field Research Center (ORFRC), in Oak Ridge, Tennessee, where the subsurface is exposed to mixed contamination predominated by uranium and nitrate. A total of 20 publications (16 published or 'in press' and 4 in review), 10 invited talks, and 43 contributed seminars/ meeting presentations were completed during the past four years of the project. PI Kostka served on one proposal review panel each year for the U.S. DOE Office of Science during the four year project period. The PI leveraged funds from the state of Florida to purchase new instrumentation that aided the project. Support was also leveraged by the PI from the Joint Genome Institute in the form of two successful proposals for genome sequencing. Draft genomes are now available for two novel species isolated during our studies and 5 more genomes are in the pipeline. We effectively addressed each of the three project objectives and research highlights are provided. Task I - Isolation and characterization of novel anaerobes: (1) A wide range of pure cultures of metal-reducing bacteria, sulfate-reducing bacteria, and denitrifying bacteria (32 strains) were isolated from subsurface sediments of the Oak Ridge Field Research Center (ORFRC), where the subsurface is exposed to mixed contamination of uranium and nitrate. These isolates which are new to science all ...
Date: June 15, 2011
Creator: Kostka, Joel E.; Kerkhof, Lee; Chin, Kuk-Jeong; Keller, Martin & Stucki, Joseph W.
Partner: UNT Libraries Government Documents Department

Final Report Spacially-Resolved Diagnostics and Modeling of Micro-Discharges

Description: Optical emission spectroscopy measurements were performed with added trace probe gases in an atmospheric pressure direct current (DC) helium microplasma. Spatially resolved measurements (resolution {approx} 6 {micro}m) were taken across a 200 {micro}m slot-type discharge. Stark splitting of the hydrogen Balmer-line was used to investigate the electric field distribution in the cathode sheath region. Electron densities were evaluated from the analysis of the spectral line broadenings of H-{beta} emission. The electron density in the bulk plasma was in the range 3-8 x 1013 cm-3. The electric field peaked at the cathode ({approx}60 kV/cm) and decayed to small values over a distance of {approx} 50 {micro}m (sheath edge) from the cathode. These experimental data were in good agreement with a self-consistent one-dimensional model of the discharge. The dependence of gas temperature on gas flow through the slot-type, atmospheric pressure microplasma in helium or argon was investigated by a combination of experiments and modeling. Spatially-resolved gas temperature profiles across the gap between the two electrodes were obtained from rotational analysis of N{sub 2} (C{sup 3}II{sub u} {yields} B{sup 3} II{sub g}) emission spectra, with small amounts of N{sub 2} added as actinometer gas. Under the same input power of 20 kW/cm{sup 3}, the peak gas temperature in helium ({approx}650 K) was significantly lower than that in argon (over 1200 K). This reflects the much higher thermal conductivity of helium gas. The gas temperature decreased with increasing gas flow rate, more so in argon compared to helium. This was consistent with the fact that conductive heat losses dominate in helium microplasmas, while convective heat losses play a major role in argon microplasmas. A plasma-gas flow simulation of the microdischarge, including a chemistry set, a compressible Navier-Stokes (and mass continuity) equation, and a convective heat transport equation, was also performed. Experimental measurements were in ...
Date: August 9, 2012
Creator: Donnelly, Vincent M. & Economou, Demetre J.
Partner: UNT Libraries Government Documents Department

MUFT-5--A FAST NEUTRON SPECTRUM PROGRAM FOR THE PHILCO-2000

Description: The program was written for the Philco-2000 computer to provide a nuclear design computing tool equivalent to the IBM-704 computer program MUFT-4 and to provide a set of routines for a future spatial multigroup program, P/sub 3/ MG-1. In addition to the features of its 704 predecessor, MUFT-5 provides a more complete isotopic edit, an optional blackness coefficient edit, and the use of a complete P/sub i/->i>s library. The resultant program is found to be easier to use because of the simplicity of running several problems, more valuable because of the many additional results that are edited, and more economical because of the changes made in programming. (auth)
Date: February 1, 1961
Creator: Bohl, H. Jr. & Hemphill, A.P.
Partner: UNT Libraries Government Documents Department

RADIOLOGICAL PHYSICS DIVISION SEMIANNUAL REPORT, JULY THROUGH DECEMBER 1960

Description: Data are presented from studies on the total Ra>s2/sup >> /ntent, radon retention, and activity of hotspots in human bones approximately 30 yr post- adiministration of Ra. Preliminary results are reported from a study of the incidence of bone tumors following injection of Pu>s2/sup >>,/a>s2/sup >>/ / sup ,/r>s9/sup >,/r Ca>s4/sup > / mice. Calculations were made of the radiation dose from hotspots formed in bone by these radioisotopes. The gamma spectra of 20 subjects who contained known quantities of K>s4/sup > /re obtained with several different sized NaI(Tl) crystals located at various points around the body. These spectra were analyzed to determine the variations in counting rates that resulted with each patient-crystal arrangement. The total-body gamma spectra of 12 unexposed employees were measured with the human spectrometer over a span of 30 mo. Data are tabulated on Co>s1/sup >>//s4/sup > /tios. The respo nse of a scintillation counter to gamma radiation asAa function of incidence angle was measured. Studies were made on the refractive index of selected optical media. Improvements were made in the design and in the scintillator solvent for a twin scintillation fast neutron detector. Measurements were made of the skeletal and soft tissue content of Ra in normal humans whose primary source of Ra was food. Calculations of the half lives and distributions of stuble Pb and Pb>s2/sup >> / the human body are discussed. Meteorological studies reported include a comparison of observed plume rise of stack effluent with values obtuined from well-known formulas, towing tank studies of horizontal turbulent air flow, and soil temperature studies. (C.H.)
Date: February 1, 1961
Partner: UNT Libraries Government Documents Department

PHYSICS DIVISION SUMMARY REPORT FOR APRIL-MAY 1960

Description: A new method for the determination of the spins of neutron resonances from capture gamma-ray spectra is described. A study of the resonance levels of Na/sup 24/ was completed up to 860 kev. The levels were analyzed up to 630 kev and the distribution of the angular momenta, neutron widths, and level spacings is given. The study of the levels of F/sup 20/, and of lithium (present in the LiF sample), was started wd data were obtained up to 280 kev. The "full" condition of a liquid-nitrogen cold trap ts detected by a small carbon resistor working inio a transistor d-c amplifier. An interesting sidelight on the loss of liquid nitrogen due to materials used in the transfer of the coolant is presented. The fluorescence spectrum of a commercial plastic scintillator was determined under various experimental conditions. Studies of the influence of temperature on the efficiency of energy transfer from naphthalene to anthracene in liquid solutions are reported. A detailed study was made of reduced widths extracted from the measured differential cross sections of stripping and pickup reactions. A method for computing the imaginary part of the Delbruck scattering amplitude was developed and applied for gamma energies of 2.62 and 6.14 Mev. The magnetic moments of the er studies. A l and Houdry ThO/sub hyperons were computed with the aid of mass spectral representations. (For preceding period see ANL- 6130.) (W.D.M.)
Date: October 31, 1960
Partner: UNT Libraries Government Documents Department

Stark broadening in hot, dense laser-produced plasmas

Description: Broadened Lyman-$alpha$ x-ray lines from neon X and argon XVIII radiators, which are immersed in a hot, dense deuterium or deuterium-tritium plasma, are discussed. In particular, these lines are analyzed for several temperature-density cases, characteristic of laser-produced plasmas; special attention paid to the relative importance of ion, electron, and Doppler effects. Static ion microfield distribution functions are tabulated.
Date: January 1, 1976
Creator: Tighe, R.J. & Hooper, C.F. Jr.
Partner: UNT Libraries Government Documents Department

LMFBR Blanket Physics Project progress report No. 2

Description: This is the second annual report of an experimental program for the investigation of the neutronics of benchmark mock-ups of LMFBR blankets. Work was devoted primarily to measurements on Blanket Mock-Up No. 2, a simulation of a typical large LMFBR radial blanket and its steel reflector. Activation traverses and neutron spectra were measured in the blanket; calculations of activities and spectra were made for comparison with the measured data. The heterogeneous self- shielding effect for $sup 238$U capture was found to be the most important factor affecting the comparison. Optimization and economic studies were made which indicate that the use of a high-albedo reflector material such as BeO or graphite may improve blanket neutronics and economics. (auth)
Date: June 30, 1971
Creator: Forbes, I.A.; Driscoll, M.J.; Rasmussen, N.C.; Lanning, D.D. & Kaplan, I. (eds.)
Partner: UNT Libraries Government Documents Department

THE EFFECT OF Cl$sup -$ AND SO$sub 4$$sup -2$ ON THE PARAMAGNETIC RESONANCE LINE WIDTH OF Mn$sup +2$ IN AQUEOUS SOLUTION AND THE RATES OF FORMATION OF THE COMPLEX IONS

Description: The line width of one of the hynerfine components in solutions of Mn(ClO/ sub 4/)/sub 2/ containing added NaCl and Na/sub 2/SO/sub 4/ was studied from 20 to 200 deg C at 9000 Mc/sec. The chloride ion contributes littie broadening at 0.1 M below 80 deg C but considerable broadening is obtained above this temperature. The sulfate contributes broadening at all temperatures. The rates of formation of inner-sphere'' and outersphere'' complexes are discussed together with their rates of relaxation. At the lower temperatures the outersphere'' complexes primarily contribute to the broadening while at the higher temperatures the inner-sphere'' complexes also contribute. From the broadening above 80%DEC the rates of formation of the inner-sphere'' complexes are evaluated. (auth)
Date: September 23, 1963
Creator: Hayes, R.G. & Myers, R.J.
Partner: UNT Libraries Government Documents Department

ORGANIC COOLANT RESEARCH SUMMARY REPORT, JULY 1, 1960-MARCH 31, 1963

Description: : : 7 : ; : = : : 9 ; 8 : ; / he use of organic liquids as reactor moderator-coolants is presented. A major part of the study was devoted to the mechanism of radiolytic damage to coolants. A mathematical treatment for handling information on the relative reactivity of different positions on an aromatic ring was developed in some detail. Determinations on products from the radiolysis of terphenyls, biphenyl, and mixtures of these with benzene indicate that free radicals may be the main reactive species generated but that others are present. Comparison of the data with reactions of chemically or photochemically generated free radicals shows that the radiolysis is not random, especially at 300 deg C, but that meta radicals are more frequently formed. Attack by the active species on another molecule is favored in the para position and repressed at the ortho position compared to the meta. The distribution of isomers found indicates that H/sub 2/ abstraction by the free radicals and isomerization reactions do not occur to an appreciable extent. New analytical methods were developed. Chromatography on a solid salt column using LiCl proved to be a very satisfactory method for quaterphenyls and most hexaphenyls. Elution peak shifts between LiCl, CsCl, and CaCl/sub 2/ columns were correlated with structure, and made possible separation and identification of certain isomers not possible on a single column. For the calibration of the columns and position identification, authentic samples of all the quaterphenyls, several quinquephenyls, and 13 hexaphenyls were obtained or synthesized by unequivocal methods. Several of these were obtained in fairly large quantity and five were new compounds. Using these known materials, important correlations were developed in the fine structure of the infrared spectra which, together with the elution peak shifting between salt columns, made possible identification of ...
Date: October 1, 1963
Creator: Hillyer, J.C.
Partner: UNT Libraries Government Documents Department

CROSS SECTIONS FOR REACTOR ANALYSIS

Description: A listing of the data on the revised tape is presented. The nuclear data are a reproduction of the computer printout. Other nuclear data (spectra, energy, absorption cross section of some poisons and absorption and fission cross sections of selected fuel materials) were transcribed from the tape listing to provide a more compact format or to allow easier comparison of absorbers and fuels. (auth)
Date: March 18, 1964
Creator: Brunner, J.M. & Henderson, W.B.
Partner: UNT Libraries Government Documents Department

Physics Verification Program. Part III, Tasks 8--11. Summary report

Description: Summary results are presented for the following PWR experimental tasks: fuel gap detectability study, capture measurements, prompt incore detector study, and 17 by 17 subassembly mockups. (DG)
Date: October 1, 1975
Creator: Baldwin, M.N.; McAdams, V.D.; Warren, H.D. & Webb, H.W.
Partner: UNT Libraries Government Documents Department

Studies of neutron dissociation at FermiLab energies

Description: The characteristics of diffraction dissociation of neutrons into p$pi$$sup -$ systems at high energies were examined. A substantial correlation is observed between the mass and the t of the produced system. The spin structure of the p$pi$$sup -$ amplitudes at low mass is very complex, but is described surprisingly well by the simple Deck Mechanism. Both $pi$-exchange and proton-exchange contributions are evident in diffractive production. The t- channel and s-channel helicity amplitudes contain comparable contributions from flip and nonflip terms and the produced states are not restricted to those expected on the basis of the Morrison rule. (auth)
Date: August 21, 1975
Creator: Ferbel, T.
Partner: UNT Libraries Government Documents Department

Argonne National Laboratory Physics Division Summary Report: September, October 1960

Description: The use and operation of the Van de Graaff generator are summarized for the period from January 1 to June 30, 1960. Molecular beam study final results are given for Mn/sup 56/, and progress on the new atomic-beam machine is reported to date. A preliminary investigation was made of the neutron total cross section of cobalt. Results are presented. The decomposition of trichlorobromomethane by the isomeric transition of 4.4-hr Br/sup 80m/ and to 1000 deg F. /sup -/, decay of 35.9-hr Br/sup 82/ was studied. The fragmnentation patterns initiated by the two nuclear transitions differ markedly, the one caused by the isomeric transition was dominated by spectra of multiply-charged atomic species, whereas the pattern due to Br/sup 82/ was entirely made up of singlycharged products. An investigition of nondiagonal matrix elements arising in a shell-model treatment of a deformed nucleus showed that their neglect in determining the degree of deformation does not lead to serious error. A previous statement, in a study of collective effects and the shell model, about K = 0 bands in odd-odd nuclei is corrected. The effect of residual interactions is calculated, and the result is applied to Ho/sup 166/. (For preceding period see ANL-6190.) (W.D.M.)
Date: October 1961
Creator: Argonne National Laboratory. Physics Division.
Partner: UNT Libraries Government Documents Department