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Computer program SCAP-BR for gamma-ray streaming through multi-legged ducts

Description: A computer program, SCAP-BR, has been developed at Burns and Roe for the gamma-ray streaming analysis through multi-legged ducts. SCAP-BR is a modified version of the single scattering code, SCAP, incorporating capabilities of handling multiple scattering and volumetric source geometries. It utilizes the point kernel integration method to calculate both the line-of-sight and scattered gamma dose rates by employing the ray tracing technique through complex shield geometries. The multiple scatter… more
Date: December 8, 1977
Creator: Byoun, T. Y.; Babel, P. J. & Dajani, A. T.
Partner: UNT Libraries Government Documents Department
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Mirror Advanced Reactor Study (MARS) final report summary

Description: The Mirror Advanced Reactor Study (MARS) has resulted in an overview of a first-generation tandem mirror reactor. The central cell fusion plasma is self-sustained by alpha heating (ignition), while electron-cyclotron resonance heating and negative ion beams maintain the electrostatic confining potentials in the end plugs. Plug injection power is reduced by the use of high-field choke coils and thermal barriers, concepts to be tested in the Tandem Mirror Experiment-Upgrade (TMX-U) and Mirror Fus… more
Date: December 8, 1983
Creator: Henning, C. D.; Logan, B. G.; Carlson, G. A.; Perkins, L. J.; Werner, R. W.; Gordon, J. D. et al.
Partner: UNT Libraries Government Documents Department
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Conversion-electron experiment to characterize the decay of the /sup 237/Np shape isomer

Description: Conversion electrons from the decay of low-lying levels of /sup 237/Np have been measured to detect the population of these levels by gamma-ray decay of the /sup 237/Np shape isomer. Analysis of the 208-keV transition L conversion-electron peak gives an upper limit of about 17 ..mu..b for the population of the 3/2/sup -/ 267-keV level in /sup 237/Np from the shape isomer decay. Model calculations are compared with the measured limit. Improvements are suggested for this experiment. 9 refs., 4 fi… more
Date: December 8, 1987
Creator: Henry, E. A.; Becker, J. A.; Bauer, R. W.; Gardner, D. G.; Decman, D. J.; Meyer, R. A. et al.
Partner: UNT Libraries Government Documents Department
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Effect of pressure on the crystal structure of ettringite

Description: X-ray diffraction and infrared data have been collected froma sample of ettringite from ambient pressure to 6.4 GPa. The sample wasfound to reversibly transform to an amorphous phase at 3 GPa. Theisothermal bulk modulus of ettringite was found to be 27(7) GPa and theincompressibilities of the lattice parameters were found to be 71(30) GPaalong a and 108(36) GPa along c.
Date: December 8, 2006
Creator: Clark, Simon M.; Colas, Bruno; Kunz, Martin; Speziale, Sergio & Monteiro, Paulo J.M.
Partner: UNT Libraries Government Documents Department
open access

Fragmentation Cross Sections of Medium-Energy 35Cl, 40Ar, and 48TiBeams on Elemental Targets

Description: Charge-changing and fragment production cross sections at 0degrees have been obtained for interactions of 290, 400, and 650MeV/nucleon 40Ar beams, 650 and 1000 MeV/nucleon 35Cl beams, and a 1000MeV/nucleon 48Ti beam. Targets of C, CH2, Al, Cu, Sn, and Pb were used.Using standard analysis methods, we obtain fragment cross sections forcharges as low as 8 for Cl and Ar beams, and as low as 10 for the Tibeam. Using data obtained with small-acceptance detectors, we reportfragment production cross se… more
Date: December 8, 2007
Creator: Zeitlin, C.; Guetersloh, S.; Heilbronn, L.; Miller, J.; Fukumura,A.; Iwata, Y. et al.
Partner: UNT Libraries Government Documents Department
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AN INNOVATIVE APPROACH FOR CONSTRUCTING AN IN-SITU BARRIER FOR STRONTIUM-90 AT THE HANFORD SITE WASHINGTON

Description: Efforts to reduce the flux of Sr-90 to the Columbia River from Hanford Site 100-N Area past-practice liquid waste disposal sites have been underway since the early 1990s. Termination of all liquid discharges to the ground in 1993 was a major step toward meeting this goal. However, Sr-90 adsorbed on aquifer solids beneath liquid waste disposal sites and extending beneath the near-shore riverbed remains a continuing contaminant source to groundwater and the Columbia River. The initial pump-and-tr… more
Date: December 8, 2008
Creator: RJ, FABRE
Partner: UNT Libraries Government Documents Department
open access

Evidence against correlations between nuclear decay rates and Earth-Sun distance

Description: We have reexamined our previously published data to search for evidence of correlations between the rates for the alpha, beta-minus, beta-plus, and electron capture decays of 22Na, 44Ti, 108Agm, 121Snm, 133Ba, and 241Am and the Earth?Sun distance. We find no evidence for such correlations and set limits on the possible amplitudes of such correlations substantially smaller than those observed in previous experiments.
Date: December 8, 2008
Creator: Norman, Eric B.; Browne, Edgardo; Shugart, Howard A.; Joshi, Tenzing H. & Firestone, Richard B.
Partner: UNT Libraries Government Documents Department
open access

HOT ELECTRON ENERGY DISTRIBUTIONS FROM ULTRA-INTENSE LASER SOLID INTERACTIONS

Description: We present experimental data of electron energy distributions from ultra-intense (>10{sup 19} W/cm{sup 2}) laser-solid interactions using the Rutherford Appleton Laboratory Vulcan petawatt laser. These measurements were made using a CCD-based magnetic spectrometer. We present details on the distinct effective temperatures that were obtained for a wide variety of targets as a function of laser intensity. It is found that as the intensity increases from 10{sup 17} W/cm{sup 2} to 10{sup 19} W/c… more
Date: December 8, 2005
Creator: Chen, H; Wilks, S C; Kruer, W L; Moon, S; Patel, N; Patel, P K et al.
Partner: UNT Libraries Government Documents Department
open access

Enhancement of Spin-Polarized Electron Emission from Strain-Compensated AlInGaAs-GaAsP Superlattices

Description: Resonance enhancement of the quantum efficiency of new polarized electron photocathodes based on a short-period strain-compensated AlInGaAs/GaAsP superlattice structure is reported. The superlattice is a part of an integrated Fabry-Perot optical cavity. We demonstrate that the Fabry-Perot resonator enhances the quantum efficiency by up to a factor 10 in the wavelength region of the main polarization maximum. The high structural quality implied by these results points to the very promising appli… more
Date: December 8, 2006
Creator: Roberts, J. S.; Yashin, Yu. P.; Mamaev, Yu. A.; Gerchikov, L. G.; Maruyama, T.; Luh, D. -A. et al.
Partner: UNT Libraries Government Documents Department
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CORRELATIONS BETWEEN PHOTOINDUCED EPR AND PHOTOCONDUCTIVITY INTONE-THF SOLUTION CHARGE-TRANSFER COMPLEX

Description: Reversible photoinduced electron paramagnetic resonance (EPR) signals and photoconductivity were observed when a solution of tetracyancethylene (TCNE) in tetrahydrofuran (THF) was irradiated in the charge-transfer band of the complex formed between these two compounds. The eleven-line hyperfine structure of the EPR spectrum which was obtained demonstrated the presence of TCNE negative ion radical. The concentration of this radical was found to be directly proportional to the square root of the … more
Date: December 8, 1964
Creator: Ilten, David F. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department
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The Evolution of Ga and As Core Levels in the Formation of Fe/GaAs(001): A High Resolution Soft X-ray Photoelectron Spectroscopic Study

Description: A high resolution soft x-ray photoelectron spectroscopic study of Ga and As 3d core levels has been conducted for Fe/GaAs (001) as a function of Fe thickness. This work has provided unambiguous evidence of substrate disrupting chemical reactions induced by the Fe overlayer--a quantitative analysis of the acquired spectra indicates significantly differing behavior of Ga and As during Fe growth, and our observations have been compared with existing theoretical models. Our results demonstrate that… more
Date: December 8, 2006
Creator: Thompson, J W; Neal, J R; Shen, T H; Morton, S A; Tobin, J G; Waddill, G D et al.
Partner: UNT Libraries Government Documents Department
open access

Coordination Complexes of Decamethylytterbocene with4,4'-Disubstituted Bipyridines: An Experimental Study of Spin Coupling inLanthanide Complexes

Description: The paramagnetic 1:1 coordination complexes of (C5Me5)2Ybwith a series of 4,4'-disubstituted bipyridines, bipy-X, where X is Me,tert-Bu, OMe, Ph, CO2Me, and CO2Et have been prepared. All of thecomplexes are paramagnetic and the values of the magnetic susceptibilityas a function of temperature show that these values are less thanexpected for the cation, [(C5Me5)2Yb(III)(bipy-X)]+, which have beenisolated as the cation-anion ion-pairs[(C5Me5)2Yb(III)(bipy-X)]+[(C5Me5)2YbI2]f fnfn where X is CO2Et… more
Date: December 8, 2005
Creator: Walter, Marc D.; Berg, David J. & Andersen, Richard A.
Partner: UNT Libraries Government Documents Department
open access

Search for a QGP with a TPC spectrometer, and QGP signals predicted by new event generator

Description: The BNL/CCNY/Johns Hopkins/Rice Collaboration has developed and successfully tested a TPC Magnetic Spectrometer to search for OGP signals produced by ion beams at AGS. Test data with 14.5 GeV/c /times/ A Oxygen ions incident on a Pb target has been obtained. These include a 78-prong nuclear interaction in the MPS magnet which was pattern recognized with an efficiency approx.75%. A cascade and plasma event generator has also been developed, the predictions of which are used to illustrate how our… more
Date: December 8, 1988
Creator: Lindenbaum, S. J.
Partner: UNT Libraries Government Documents Department
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Implementing the theories: A fully integrated project control system that`s implemented and works

Description: Using the theories presented in DOE Orders 4700.1, 1332.1A, and Notice 4700.5 as the basis for system design, the Fernald Environmental Restoration Management Corporation (FERMCO) has developed and implemented a Project Control System (PCS) that complies with requirements and provides DOE and FERMCO management with timely performance measurement information. To this extent, the FERMCO PCS probably is similar to the systems of the majority of the contractors in the DOE complex. In fact. this fac… more
Date: December 8, 1994
Creator: Harris, R. E.
Partner: UNT Libraries Government Documents Department
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Tests of a New Cloud Treatment in an Atmospheric General Circulation Model

Description: In this study we present a new cloud treatment in an atmospheric climate model. The water (or ice) content of clouds is a introduced as a prognostic variable, subject to both advective and diffusive transport. In the first phase of the study, the cloud water does not affect the radiative properties of clouds. We then find differences in precipitation and cloud fields, but little effect on the overall climate. In the second phase the cloud water determines the reflectivity of the clouds. This ca… more
Date: December 8, 1993
Creator: Kristjansson, J. E.
Partner: UNT Libraries Government Documents Department
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INSTALLATION OF BUBBLERS IN THE SAVANNAH RIVER SITED DEFENSE WASTE PROCESSING FACILITY MELTER

Description: Savannah River Remediation (SRR) LLC assumed the liquid waste contract at the Savannah River Site (SRS) in the summer of 2009. The main contractual agreement was to close 22 High Level Waste (HLW) tanks in eight years. To achieve this aggressive commitment, faster waste processing throughout the SRS liquid waste facilities will be required. Part of the approach to achieve faster waste processing is to increase the canister production rate of the Defense Waste Processing Facility (DWPF) from app… more
Date: December 8, 2010
Creator: Smith, M. & Iverson, D.
Partner: UNT Libraries Government Documents Department
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AFFECTS OF MECHANICAL MILLING AND METAL OXIDE ADDITIVES ON SORPTION KINETICS OF 1:1 LiNH2/MgH2 MIXTURE

Description: The destabilized complex hydride system composed of LiNH{sub 2}:MgH{sub 2} (1:1 molar ratio) is one of the leading candidates of hydrogen storage with a reversible hydrogen storage capacity of 8.1 wt%. A low sorption enthalpy of {approx}32 kJ/mole H{sub 2} was first predicted by Alapati et al. utilizing first principle density function theory (DFT) calculations and has been subsequently confirmed empirically by Lu et al. through differential thermal analysis (DTA). This enthalpy suggests that f… more
Date: December 8, 2010
Creator: Erdy, C.; Anton, D. & Gray, J.
Partner: UNT Libraries Government Documents Department
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Multi-step laser spectroscopy in atomic uranium. [Crossed beams]

Description: The use of multistep photoionization techniques to measure lifetimes, cross sections, and branching ratios in uranium is described. The measurement of autoionization behavior, the assignment of new levels, and the observation of Rydberg states are also described. Experimental data are presented for all parameters. (auth)
Date: December 8, 1975
Creator: Solarz, R. W.; Paisner, J. A.; Carlson, L. R.; May, C. A. & Johnson, S. A.
Partner: UNT Libraries Government Documents Department
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A new model for solvent extraction in columns

Description: A new model was developed for analyzing solvent extraction processes carried out in columns. Each column is treated as a series of well-defined equilibrium stages where the backmixing (other-phase carryover) between stages can be large. By including all mass transfer effects in the backmixing value, the same number of stages can be used for all extracted components no matter what their distribution coefficients. This greatly simplifies the calculations required when modeling multicomponent solv… more
Date: December 8, 1989
Creator: Leonard, R. A.; Regalbuto, M. C.; Chamberlain, D. B. & Vandegrift, G. F.
Partner: UNT Libraries Government Documents Department
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Comparing Vacuum and Extreme Ultraviolet Radiation for Postionization of Laser Desorbed Neutrals from Bacterial Biofilms and Organic Fullerene

Description: Vacuum and extreme ultraviolet radiation from 8 - 24 eV generated at a synchrotron was used to postionize laser desorbed neutrals of antibiotic-treated biofilms and a modified fullerene using laser desorption postionization mass spectrometry (LDPI-MS). Results show detection of the parent ion, various fragments, and extracellular material from biofilms using LDPI-MS with both vacuum and extreme ultraviolet photons. Parent ions were observed for both cases, but extreme ultraviolet photons (16-24… more
Date: December 8, 2010
Creator: Gaspera, Gerald L.; Takahashi, Lynelle K.; Zhou, Jia; Ahmed, Musahid; Moored, Jerry F. & Hanley, Luke
Partner: UNT Libraries Government Documents Department
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A theoretical study of the ground state and lowest excited states of PuO0/+/+2 and PuO20/+/+2

Description: The ground and excited states of neutral and cationic PuO and PuO2 have been studied with multiconfigurational quantum chemical methods followed by second order perturbation theory, the CASSCF/CASPT2 method. Scalar relativistic effects and spin-orbit coupling have been included in the treatment. As literature values for the ionization energy of PuO2 are in the wide range of ~;;6.6 eV to ~;;10.1 eV, a central goal of the computations was to resolve these discrepancies; the theoretical results in… more
Date: December 8, 2008
Creator: Gibson, John K.; La Macchia, Giovanni; Infante, Ivan; Gagliardi, Laura & Raab, Juraj
Partner: UNT Libraries Government Documents Department
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Thermo-Mechanical Response of a TRISO Fuel Particle in a Fusion/Fission Engine for Incineration of Weapons Grade Plutonium

Description: The Laser Inertial Fusion-based (LIFE) engine is an advanced energy concept under development at Lawrence Livermore National Laboratory (LLNL). LIFE engine could be used to drive a subcritical fission blanket with fertile or fissile fuel. Current LIFE engine designs envisages fuel in pebble bed form with TRISO (tristructural isotropic) particles embedded in a graphite matrix, and pebbles flowing in molten salt Flibe (2LiF+BeF{sub 2}) coolant at T {approx} 700C. Weapons-grade plutonium (WGPu) fu… more
Date: December 8, 2009
Creator: Caro, M.; DeMange, P.; Marian, J. & Caro, A.
Partner: UNT Libraries Government Documents Department
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Gas-Phase Reactions of Doubly Charged Lanthanide Cations with Alkanes and Alkenes. Trends in Metal(2+) Reactivity

Description: The gas-phase reactivity of doubly-charged lanthanide cations, Ln2+ (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu), with alkanes (methane, ethane, propane, n-butane) and alkenes (ethene, propene, 1-butene) was studied by Fourier transform ion cyclotron resonance mass spectrometry. The reaction products consisted of different combinations of doubly-charged organometallic ions?adducts or species formed via metal-ion-induced hydrogen, dihydrogen, alkyl, or alkane eliminations from t… more
Date: December 8, 2008
Creator: Gibson, John K.; Marcalo, Joaquim; Santos, Marta; Pires de Matos, Antonio & Haire, Richard G.
Partner: UNT Libraries Government Documents Department
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THE RETRIEVAL KNOWLEDGE CENTER EVALUATION OF LOW TANK LEVEL MIXING TECHNOLOGIES FOR DOE HIGH LEVEL WASTE TANK RETRIEVAL 10516

Description: The Department of Energy (DOE) Complex has over two-hundred underground storage tanks containing over 80-million gallons of legacy waste from the production of nuclear weapons. The majority of the waste is located at four major sites across the nation and is planned for treatment over a period of almost forty years. The DOE Office of Technology Innovation & Development within the Office of Environmental Management (DOE-EM) sponsors technology research and development programs to support process… more
Date: December 8, 2009
Creator: Fellinger, A.
Partner: UNT Libraries Government Documents Department
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