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High Intensity Ion Beam Injection Into the 88-Inch Cyclotron

Description: Low cross section experiments to produce super-heavyelements have increased the demand for high intensity heavy ion beams atenergies of about 5 MeV/nucleon at the 88-Inch Cyclotron at the LawrenceBerkeley National Laboratory. Therefore, efforts are underway to increasethe overall ion beam transmission through the axial injection line andthe cyclotron. The ion beam emittance has been measured for various ionmasses and charge states. Beam transport simulations including spacecharge effects were p… more
Date: May 31, 2000
Creator: Wutte, Daniela; Clark, Dave J.; Laune, Bernard; Leitner,Matthaeus A. & Lyneis, Claude M.
Partner: UNT Libraries Government Documents Department
open access

HCCI engine control by thermal management

Description: This work investigates a control system for HCCI engines, where thermal energy from exhaust gas recirculation (EGR) and compression work in the supercharger are either recycled or rejected as needed. HCCI engine operation is analyzed with a detailed chemical kinetics code, HCT (Hydrodynamics, Chemistry and Transport), that has been extensively modified for application to engines. HCT is linked to an optimizer that determines the operating conditions that result in maximum brake thermal efficien… more
Date: May 11, 2000
Creator: Martinez-Frias, J; Aceves, S M; Flowers, D; Smith, J R & Dibble, R
Partner: UNT Libraries Government Documents Department
open access

Revealing myths about people, energy and buildings

Description: In this essay we take a closer look at some energy myths, focusing on the ways energy professionals and the public alike, talk, write and teach about how energy affects the way in which we design, operate, retrofit and inhabit buildings. What myths about people, energy and buildings are current today? Who tells these myths and why do we believe them? How do myths affect our behavior? Myths are a way of understanding the world we live in. They may represent incomplete understanding, or be based … more
Date: May 1, 2000
Creator: Diamond, R. & Moezzi, M.
Partner: UNT Libraries Government Documents Department
open access

A PWR Thorium Pin Cell Burnup Benchmark

Description: As part of work to evaluate the potential benefits of using thorium in LWR fuel, a thorium fueled benchmark comparison was made in this study between state-of-the-art codes, MOCUP (MCNP4B + ORIGEN2), and CASMO-4 for burnup calculations. The MOCUP runs were done individually at MIT and INEEL, using the same model but with some differences in techniques and cross section libraries. Eigenvalue and isotope concentrations were compared on a PWR pin cell model up to high burnup. The eigenvalue compar… more
Date: May 1, 2000
Creator: Weaver, Kevan Dean; Zhao, X.; Pilat, E. E & Hejzlar, P.
Partner: UNT Libraries Government Documents Department
open access

Residual Stress Determination from a Laser-Based Curvature Measurement

Description: Thermally sprayed coating characteristics and mechanical properties are in part a result of the residual stress developed during the fabrication process. The total stress state in a coating/substrate is comprised of the quench stress and the coefficient of thermal expansion (CTE) mismatch stress. The quench stress is developed when molten particles impact the substrate and rapidly cool and solidify. The CTE mismatch stress results from a large difference in the thermal expansion coefficients of… more
Date: May 1, 2000
Creator: Swank, William David; Gavalya, Rick Allen; Wright, Julie Knibloe & Wright, Richard Neil
Partner: UNT Libraries Government Documents Department
open access

Implementation of the INEEL Safety Analyst Training Standard

Description: The Idaho Nuclear Technology and Engineering Center (INTEC) safety analysis units at the Idaho National Engineering and Environmental Laboratory (INEEL) are in the process of implementing the recently issued INEEL Safety Analyst Training Standard (STD-1107). Safety analyst training and qualifications are integral to the development and maintenance of core safety analysis capabilities. The INEEL Safety Analyst Training Standard (STD-1107) was developed directly from EFCOG Training Subgroup draft… more
Date: May 1, 2000
Creator: Hochhalter, E Eugene
Partner: UNT Libraries Government Documents Department
open access

The Effect of Pretreatments on Surfactin Production From Potato Process Effluent by Bacillus Subtilis

Description: Pretreatment of low-solids (LS) potato process effluent was tested for potential to increase surfactin yield. Pretreatments included heat, removal of starch particulates, and acid hydrolysis. Elimination of contaminating vegetative cells was necessary for surfactin production. After autoclaving, 0.40 g/L of surfactin was produced from the effluent in 72 h, versus 0.24 g/L in the purified potato starch control. However, surfactin yields per carbon consumed were 76% lower from process effluent. R… more
Date: May 1, 2000
Creator: Thompson, David Neal; Fox, Sandra Lynn & Bala, Greg Alan
Partner: UNT Libraries Government Documents Department
open access

Production of Bacterial Cellulose from Alternate Feedstocks

Description: Production of bacterial cellulose by Acetobacter xylinum ATCC 10821 and 23770 in static cultures was tested from unamended food process effluents. Effluents included low- and high-solids potato effluents (LS & HS), cheese whey permeate (CW), and sugar beet raffinate (CSB). Strain 23770 produced 10% less cellulose from glucose than did 10821, and diverted more glucose to gluconate. Unamended HS, CW, and CSB were unsuitable for cellulose production by either strain, while LS was unsuitable for pr… more
Date: May 1, 2000
Creator: Thompson, David Neil & Hamilton, Melinda Ann
Partner: UNT Libraries Government Documents Department
open access

The structure of the alpha-Al2O3(0001) surface from low-energyelectron diffraction: Al termination and evidence for large thermalvibrations

Description: We have determined the surface structure of alpha-Al2O3(0001) using dynamical low-energy electron diffraction (LEED). Sapphire surfaces were prepared in three different ways, and the diffraction results were analyzed using an exhaustive search of possible models. For all sample processing conditions, the clearly favored structure has a single Al layer termination and a large first interlayer contraction. In addition, we find that the surface atoms have unusually large vibrational amplitudes at … more
Date: May 5, 2000
Creator: Soares, E. A.; Van Hove, M. A.; Walters, C. F. & McCarty, K. F.
Partner: UNT Libraries Government Documents Department
open access

Strings in AdS{sub 3} and the SL(2,R) WZW Model. Part 1: The spectrum

Description: In this paper we study the spectrum of bosonic string theory on AdS{sub 3}. We study classical solutions of the SL(2,R) WZW model, including solutions for long strings with non-zero winding number. We show that the model has a symmetry relating string configurations with different winding numbers. We then study the Hilbert space of the WZW model, including all states related by the above symmetry. This leads to a precise description of long strings. We prove a no-ghost theorem for all the repre… more
Date: May 19, 2000
Creator: Maldacena, Juan & Ooguri, Hirosi
Partner: UNT Libraries Government Documents Department
open access

Application issues for large-area electrochromic windows incommercial buildings

Description: Projections of performance from small-area devices to large-area windows and enterprise marketing have created high expectations for electrochromic glazings. As a result, this paper seeks to precipitate an objective dialog between material scientists and building-application scientists to determine whether actual large-area electrochromic devices will result in significant performance benefits and what material improvements are needed, if any, to make electrochromics more practical for commerci… more
Date: May 1, 2000
Creator: Lee, Eleanor S. & DiBartolomeo, D.L.
Partner: UNT Libraries Government Documents Department
open access

MSW effects in vacuum oscillations

Description: We point out that for solar neutrino oscillations with the mass-squared difference of {Delta}m{sup 2} {approx} 10{sup -10} - 10{sup -9} eV{sup 2}, traditionally known as ''vacuum oscillation'' range, the solar matter effects are non-negligible, particularly for the low energy pp neutrinos. One consequence of this is that the values of the mixing angle {theta} and {pi}/2 - {theta} are not equivalent, leading to the need to consider the entire physical range of the mixing angle 0 {le} {theta} {le… more
Date: May 18, 2000
Creator: Friedland, Alexander
Partner: UNT Libraries Government Documents Department
open access

Assessment of Chemical and Radiological Vulnerabilities

Description: Following the May 14, 1997 chemical explosion at Hanford's Plutonium Reclamation Facility, the Department of Energy Richland Operations Office and its prime contractor, Fluor Hanford, Inc., completed an extensive assessment to identify and address chemical and radiological safety vulnerabilities at all facilities under the Project Hanford Management Contract. This was a challenging undertaking because of the immense size of the problem, unique technical issues, and competing priorities. This pa… more
Date: May 17, 2000
Creator: SETH, S.S.
Partner: UNT Libraries Government Documents Department
open access

Managing Performance Analysis with Dynamic Statistical Projection Pursuit

Description: Computer systems and applications are growing more complex. Consequently, performance analysis has become more difficult due to the complex, transient interrelationships among runtime components. To diagnose these types of performance issues, developers must use detailed instrumentation to capture a large number of performance metrics. Unfortunately, this instrumentation may actually influence the performance analysis, leading the developer to an ambiguous conclusion. In this paper, we introduc… more
Date: May 22, 2000
Creator: Vetter, J.S. & Reed, D.A.
Partner: UNT Libraries Government Documents Department
open access

Extreme Ultraviolet Lithography - Reflective Mask Technology

Description: EUVL mask blanks consist of a distributed Bragg reflector made of 6.7nm-pitch bi-layers of MO and Si deposited upon a precision Si or glass substrate. The layer deposition process has been optimized for low defects, by application of a vendor-supplied but highly modified ion-beam sputter deposition system. This system is fully automated using SMIF technology to obtain the lowest possible environmental- and handling-added defect levels. Originally designed to coat 150mm substrates, it was upgrad… more
Date: May 9, 2000
Creator: Walton, C. C.; Kearney, P. A.; Mirkarimi, P. B.; Bowers, J. M.; Cerjan, C.; Warrick, A. L. et al.
Partner: UNT Libraries Government Documents Department
open access

Fluctuation-Dissipation Process Without a Time Scale

Description: Article discussing the fluctuation-dissipation process without a time scale.
Date: May 2000
Creator: Annunziato, Mario; Grigolini, Paolo & Riccardi, Juri
Partner: UNT College of Arts and Sciences
open access

Particle Control in the Sustained Spheromak Physics Experiment

Description: In this paper we report on density and impurity measurements in the Sustained Spheromak Physics Experiment (SSPX) which has recently started operation. The SSPX spheromak plasma is sustained by coaxial helicity injection for a duration of 2msec with peak toroidal currents of up to 0.5MA. The plasma-facing components consist of tungsten-coated copper to minimize sputtering. The surfaces are conditioned by a combination of baking at 150 C, glow discharge cleaning, Titanium gettering, and pulse-di… more
Date: May 1, 2000
Creator: Wood, R. D.; Hill, D. N.; Hooper, E. B.; Buchenauer, D.; McLean, H.; Wang, Z. et al.
Partner: UNT Libraries Government Documents Department
open access

Highly-Resolved LES of the Stable Boundary Layer Over Terrain

Description: One of the most important scenarios for atmospheric modelers is the stable boundary layer (SBL). Airborne material released near the ground will likely be trapped near the ground in high concentrations due to the reduced dispersion in the SBL. Hence the SBL is often the worst case scenario for studies of health impacts from routine or accidental release of toxic materials to the atmosphere. Unfortunately the SBL is very challenging to understand and model correctly. There is also a limited numb… more
Date: May 31, 2000
Creator: Calhoun, R.; Cederwall, R.T.; Stevens, D. & Street, R.
Partner: UNT Libraries Government Documents Department
open access

Berkeley Lab's ALS generates Femtosecond Synchrotron Radiation

Description: A Lawrence Berkeley National Laboratory (Berkeley Lab) team drawing its members from the Materials Sciences Division (MSD), the Center for Beam Physics in the Accelerator and Fusion Research Division, and the Advanced Light Source (ALS) has succeeded in generating 300-femtosecond pulses of synchrotron radiation at the ALS synchrotron radiation machine. Though this ''proof-of-principle'' experiment made use of visible light on a borrowed beamline, the laser ''time-slicing'' technique at the hear… more
Date: May 23, 2000
Creator: Robinson, Arthur L.
Partner: UNT Libraries Government Documents Department
open access

A Sensitivity Study of the Urban Effect on a Regional-Scale Model: An Idealized Case

Description: Urban infrastructure impacts the surface and atmospheric properties, such as wind, temperature, turbulence and radiation budgets. The well-recognized urban heat island phenomenon, characterized by the temperature contrast between the city and the surrounding rural area, is one such impact. Many field experiments have been conducted to study the urban heat island effect, which is typically most intense under clear sky and weak ambient wind conditions at night. In some cases, a cool island may ev… more
Date: May 30, 2000
Creator: Chin, H. N. S.; Leach, M. J. & Brown, M. J.
Partner: UNT Libraries Government Documents Department
open access

Contamination Control Techniques

Description: Welcome to a workshop on contamination Control techniques. This work shop is designed for about two hours. Attendee participation is encouraged during the workshop. We will address different topics within contamination control techniques; present processes, products and equipment used here at Hanford and then open the floor to you, the attendees for your input on the topics.
Date: May 16, 2000
Creator: EBY, J.L.
Partner: UNT Libraries Government Documents Department
open access

Potential Vulnerability Issues for Drum-Type Packages

Description: Type B and Type A fissile drum packages are required to undergo a series of tests that simulate both normal conditions of transport (NCT) and hypothetical accident conditions (HAC) as specified in 10 CFR Part 71. In particular for HAC, it must be demonstrated that the package can withstand a 30 ft. drop in the most unfavorable orientation without damage that would compromise its ability to survive a subsequent regulatory fire test. Historically, it has usually been assumed that the most unfavor… more
Date: May 24, 2000
Creator: Hagler, L. B.; Sheaffer, M. K.; Anderson, B. L.; Hafner, R. S. & Witte, M. C.
Partner: UNT Libraries Government Documents Department
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