9,943 Matching Results

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Campus Chaplains: Cult Training and Perceptions

Description: This article examines the perception of 43 college chaplains across the United States with regard to cult training and perceptions of college and university cult activity.
Date: June 2004
Creator: Elleven, Russell K.; Greenhaw, Kimberly J. & Allen, Jeff M.
Partner: UNT College of Information

Equivalence of dipole correction and Coulomb cutoff techniques in supercell calculations

Description: Article on the equivalence of dipole correction and Coulomb cutoff techniques in supercell calculations. In this work, the authors compare the dipole correction and Coulomb cutoff methods under the same conditions in the framework of plane-wave based density-functional theory.
Date: June 3, 2008
Creator: Yu, Liping; Ranjan, Vivek; Lu, W.; Bernholc, Jerry & Buongiorno Nardelli, Marco
Partner: UNT College of Arts and Sciences

Atmospheric chemistry of isopropyl formate and tert-butyl formate

Description: Article on the atmospheric chemistry of isopropyl formate and tert-butyl formate.
Date: August 21, 2009
Creator: Pimentel, Andre Silva; Tyndall, Geoffrey S. (Geoffrey Stuart) 1955-; Orlando, John J.; Hurley, Michale D.; Wallington, Timothy J.; Sulbaek Andersen, Mads Peter et al.
Partner: UNT College of Arts and Sciences

Enthalpy of Formation of the Cyclohexadienyl Radical and the C-H Bond Enthalpy of 1,4-Cyclohexadiene: An Experimental and Computational Re-Evaluation

Description: Article on an experimental and computational re-evaluation and the enthalpy of formation of the cyclohexadienyl radical and the C-H bond enthalpy of 1,4-cyclohexadiene.
Date: June 2, 2009
Creator: Gao, Yide; DeYonker, Nathan J.; Garrett, E. Chauncey; Wilson, Angela K.; Cundari, Thomas R., 1964- & Marshall, Paul
Partner: UNT College of Arts and Sciences

Development of small, fast reactor core designs using lead-based coolant.

Description: A variety of small (100 MWe) fast reactor core designs are developed, these include compact configurations, long-lived (15-year fuel lifetime) cores, and derated, natural circulation designs. Trade studies are described which identify key core design issues for lead-based coolant systems. Performance parameters and reactivity feedback coefficients are compared for lead-bismuth eutectic (LBE) and sodium-cooled cores of consistent design. The results of these studies indicate that the superior neutron reflection capability of lead alloys reduces the enrichment and burnup swing compared to conventional sodium-cooled systems; however, the discharge fluence is significantly increased. The size requirement for long-lived systems is constrained by reactivity loss considerations, not fuel burnup or fluence limits. The derated lead-alloy cooled natural circulation cores require a core volume roughly eight times greater than conventional compact systems. In general, reactivity coefficients important for passive safety performance are less favorable for the larger, derated configurations.
Date: June 11, 1999
Creator: Cahalan, J. E.; Hill, R. N.; Khalil, H. S. & Wade, D. C.
Partner: UNT Libraries Government Documents Department

Polarized proton acceleration program at the AGS and RHIC

Description: Presented is an overview of the program for acceleration of polarized protons in the AGS and their injection into the RHIC collider. The problem of depolarizing resonances in strong focusing circulator accelerators is discussed. The intrinsic resonances are jumped over by the fast tune jump, and a partial Siberian Snake is used to compensate for over forty imperfection resonances in the AGS. Two sets of full Siberian Snake and spin rotators will be employed in RHIC.
Date: June 1995
Creator: Lee, Y. Y.
Partner: UNT Libraries Government Documents Department

Microstructural development in waste form alloys cast from irradiated cladding residual from the electrometallurgical treatment of EBR-II spent fuel.

Description: A metallic waste form alloy that consists primarily of stainless steel and zirconium is being developed by Argonne National Laboratory to contain metallic waste constituents that are residual from an electrometallurgical treatment process for spent nuclear fuel. Ingots have been cast in an induction furnace in a hot cell using actual, leftover, irradiated, EBR-II cladding hulls treated in an electrorefiner. The as-cast ingots have been sampled using a core-drilling and an injection-casting technique. In turn, generated samples have been characterized using chemical analysis techniques and a scanning electron microscope equipped with energy dispersive and wavelength-dispersive spectrometers. As-cast ingots contain the predicted concentration levels of the various constituents, and most of the phases that develop are analogous to those for alloys generated using non-radioactive surrogates for the various fission products.
Date: June 10, 1999
Creator: Keiser, D. D., Jr.
Partner: UNT Libraries Government Documents Department

Issue Management Risk Ranking Systems

Description: Thousands of safety issues have been collected on-line at the Idaho National Engineering and Environmental Laboratory (INEEL) as part of the Issue Management Plan. However, there has been no established approach to prioritize collected and future issues. The authors developed a methodology, based on hazards assessment, to identify and risk rank over 5000 safety issues collected at INEEL. This approach required that it was easily applied and understandable for site adaptation and commensurate with the Integrated Safety Plan. High-risk issues were investigated and mitigative/preventive measures were suggested and ranked based on a cost-benefit scheme to provide risk-informed safety measures. This methodology was consistent with other integrated safety management goals and tasks providing a site-wide risk-informed decision tool to reduce hazardous conditions and focus resources on high-risk safety issues. As part of the issue management plan, this methodology was incorporated at the issue collection level and training was provided to management to better familiarize decision-makers with concepts of safety and risk. This prioritization methodology and issue dissemination procedure will be discussed. Results of issue prioritization and training efforts will be summarized. Difficulties and advantages of the process will be reported. Development and incorporation of this process into INEEL's lessons learned reporting and the site-wide integrated safety management program will be shown with an emphasis on establishing self reliance and ownership of safety issues.
Date: June 1, 1999
Creator: Marshall, F. M.; Grant, G. M.; Stromberg, H. M. & Novack, S. D.
Partner: UNT Libraries Government Documents Department

Application of RBS and NRA in the fabrication of carbon based devices

Description: We have used Nuclear Reaction Analysis (NRA) and Rutherford Backscattering Spectrometry (RBS) as well as resonant backscattering as analytical tools in fabricating carbon based drug delivery bio-implants, electrodes for batteries, and devices to entrap or filter specific toxins. Precursor is resol C{sub 7}H{sub 8}O{sub 2} liquid, which converts to fully cured phenolic resin C{sub 7}H{sub 6}O (sp gr 1.25) on heating at 170 C. This resin further transforms with no change in shape to glassy carbon (sp gr 1.45) on heating to 1000 C. Final product consists of long ribbon-like molecules of sp2 carbon atoms aggregated locally to form subcrystalline domains arranged randomly in space. RBS and NRA were used in measuring the porosity before and after activation, in concentration profiling of stored drugs before and after leaching, in detecting low level light element impurities, and in detecting changes in the structure of the device due to fabrication.
Date: June 1, 1995
Creator: Ila, D.; Zimmerman, R.L.; Maleki, H.; Evelyn, A.L. & Poker, D.B.
Partner: UNT Libraries Government Documents Department

RESULTS FROM BETATRON PHASE MEASUREMENTS IN RHIC DURING THE SEXTANT TEST.

Description: The Sextant Test of the Relativistic Heavy Ion Collider (RHIC) was an important step towards its completion. One sixth of the two RHIC accelerators was fully commissioned. Gold ion beam was injected and transported through one sextant of one of the two rings. The betatron phase advance per cell was measured by recording differences in the horizontal and vertical positions of the beam at the end of the sextant due to a sequence of correction dipole kicks along the beam line. Measurement results show excellent agreement with predicted values, confirming that production measurements of the integral functions of the quadrupoles were very accurate, and that the polarity of all elements (correction dipoles, quadrupoles, dipoles etc.) was correct.
Date: June 26, 1998
Creator: TRBOJEVIC, D.
Partner: UNT Libraries Government Documents Department

Rapid mold replication

Description: The desire to reduce tooling costs have driven manufacturers to investigate new manufacturing methods and materials. In the plastics injection molding industry replicating molds to meet production needs is time consuming (up to 6 months) and costly in terms of lost business. We have recently completed a feasibility study demonstrating the capability of high rate Electron Beam Physical Vapor Deposition (EBPVD) in producing mold inserts in days, not months. In the current practice a graphite mandrel, in the shape of the insert`s negative image, was exposed to a jet of metal vapor atoms emanating from an electron beam heated source of an aluminum-bronze alloy. The condensation rate of the metal atoms on the mandrel was sufficient to allow the deposit to grow at over 30 {mu}m/min or 1.2 mils per minute. The vaporization process continued for approximately 14 hours after which the mandrel and deposit were removed from the EBPVD vacuum chamber. The mandrel and condensate were easily separated resulting in a fully dense aluminum-bronze mold insert about 2.5 cm or one inch thick. This mold was subsequently cleaned and drilled for water cooling passages and mounted on a fixture for operation in an actual injection molding machine. Results of the mold`s operation were extremely successful showing great promise for this technique. This paper describes the EBPVD feasibility demonstration in more detail and discusses future development work needed to bring this technique into practice.
Date: June 1, 1995
Creator: Heestand, G.M.; Beeler, R.G. Jr. & Brown, D.L.
Partner: UNT Libraries Government Documents Department

Results on Fermilab main injector dipole measurements

Description: Measurements of the Productions run of Fermilab Main Injector Dipole magnets is underway. Redundant strength measurements provide a set of data which one can fit to mechanical and magnetic properties of the assembly. Plots of the field contribution from the steel supplement the usual plots of transfer function (B/I) vs. I in providing insight into the measured results.
Date: June 1, 1995
Creator: Brown, B.C.; Baiod, R.; DiMarco, J.; Glass, H.D.; Harding, D.J.; Martin, P.S. et al.
Partner: UNT Libraries Government Documents Department

Vitrification of Rocky Flats ash followed by encapsulation in the Defense Waste Processing Facility

Description: The Department of Energy (DOE) manages approximately 10 to 20 metric tons of plutonium in the form of scrap, residues, oxides, ash, metal, sludge, compounds, etc. Not all of this material is chemically stable or is packaging acceptable for storage. Thus, it constitutes a potential hazard to employees and to the public. This paper describes a relatively simple concept for stabilizing most of this type of plutonium by converting it into encapsulated glass. A full-scale hot demonstration of the concept is proposed, in which Rock Flats ash would be vitrified and sealed in small cans, followed by encapsulation of the cans in Defense Waste Processing Facility canisters with high-level glass.
Date: June 1, 1996
Creator: Becker, G.W. Jr. & McKibben, J.M.
Partner: UNT Libraries Government Documents Department

Fast neutron radiography research at ANL-W

Description: Thirty-seven different elements were tested for their suitability as converter screens for direct and indirect fast neutron radiography. The use of commercial X-ray scintillator screens containing YTaO{sub 4}, LaOBr:Tm, YTaO{sub 4}:Nb, YTaO{sub 4}:Tm, CaWO{sub 4}, BaSO{sub 4}:Sr, and GdO{sub 2}S:Tb was also explored for direct fast neutron radiography. For the indirect radiographic process, only one element, holmium, was found to be better than copper. Iron was also found to work as well as copper. All other elements that were tested were inferior to copper for indirect fast neutron radiography. For direct fast neutron radiography, the results were markedly different. Copper was found to be a poor material to sue, as thirty-two of the elements performed better than the copper. Tantalum was found to be the best material to use. Several other materials that also performed remarkably well include, in order of decreasing utility, gold, lutetium, germanium, dysprosium, and thulium. Several interesting results were obtained for the commercial X-ray scintillator screens. Most notably, useful radiographs were produced with all of the various scintillation screens. However, the screens containing YTaO{sub 4}:Nb offered the greatest film densities for the shortest exposure times. Screens using GdSO{sub 4}:Tb provided the best resolution and clearest images at the sacrifice of exposure time. Also, as previous researchers found, scintillator screens offered significantly shorter exposure times than activation foils.
Date: June 1, 1996
Creator: Klann, R.T. & Natale, M.D.
Partner: UNT Libraries Government Documents Department