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USDOE LABORATORY VIEWS ON U.S.-RUSSIAN PARTNERSHIP FOR NUCLEAR SECURITY. (open access)

USDOE LABORATORY VIEWS ON U.S.-RUSSIAN PARTNERSHIP FOR NUCLEAR SECURITY.

This paper summarizes an analysis of the U.S.-Russian Nuclear Material Protection, Control and Accounting (MPC&A) Program, developed on the basis of extensive discussions with U.S. laboratory participants as well as personal experience. Results of the discussions have been organized into three main areas: Technical/MPC&A Progress; Programmatic and Administrative Issues; and Professional Aspects, Implications for MPC&A effectiveness, for MPC&A sustainability, and for future relations and collaboration are derived. Suggested next steps are given.
Date: July 26, 1998
Creator: KEMPF,C. R.
System: The UNT Digital Library
Lessons Learned from the NREL Village Power Program (open access)

Lessons Learned from the NREL Village Power Program

Renewable energy solutions for village power applications can be economical, functional, and sustainable. Pilot projects are an appropriate step in the development of a commercially viable market for rural renewable energy solutions. Moreover, there are a significant number of rural electrification projects under way that employ various technologies, delivery mechanisms, and financing arrangements. These projects, if properly evaluated, communicated, and their lessons incorporated in future projects and programs, can lead the way to a future that includes a robust opportunity for cost-effective, renewable-based village power systems. This paper summarizes some of NRELs recent experiences and lessons learned.
Date: July 1, 1998
Creator: Taylor, R.
System: The UNT Digital Library
Photochemical Solar Cells Based on Dye-Sensitization of Nanocrystalline TiO2 (open access)

Photochemical Solar Cells Based on Dye-Sensitization of Nanocrystalline TiO2

A photoelectrochemical solar cell that is based on the dye-sensitization of thin nanocrystalline films of TiO2 (anatase) nanoparticles in contact with a non-aqueous liquid electrolyte is described. The cell, fabricated at NREL, shows a conversion efficiency of -9.2% at AM1.5, which approaches the best reported value of 10%-11% by Grtzel at EPFL in Lausanne, Switzerland. The femtosecond (fs) pump-probe spectroscopy has been used to time resolve the injection of electrons into the conduction band of nanocrystalline TiO2 films under ambient conditions following photoexcitation of the adsorbed Ru(11)-complex dye. The measurement indicates an instrument-limited -50 fs upper limit on the electron injection time. We also report the sensitization of nanocrystalline TiO2 by a novel iron-based dye, CIS-[Fe 11 (2,2'-bipyridine-4,4'-dicarboxylic acid)2 (CN)2], a chromophore with an extremely short-lived, nonemissive excited state. The dye also exhibits a unique"band selective" sensitization through one of its two absorption bands. The operational principle of the device has been studied through the measurement of electric field distribution within the device structure and studies on the pH dependence of dye-redox potential. The incorporation of WO3 -based electrochromic layer into this device has led to a novel photoelectrochromic device structure for"smart window" application.
Date: July 1, 1998
Creator: Deb, S. K.; Ellingson, R.; Ferrere, S.; Frank, A. J.; Gregg, B. A.; Nozik, A. J. et al.
System: The UNT Digital Library
Determination of the radionuclide release factor for an evaporator process using nondestructive assay (open access)

Determination of the radionuclide release factor for an evaporator process using nondestructive assay

The 242-A Evaporator is the primary waste evaporator for the Hanford Site radioactive liquid waste stored in underground double-shell tanks. Low pressure evaporation is used to remove water from the waste, thus reducing the amount of tank space required for storage. The process produces a concentrated slurry, a process condensate, and an offgas. The offgas exhausts through two stages of high-efficiency particulate air (HEPA) filters before being discharged to the atmosphere 40 CFR 61 Subpart H requires assessment of the unfiltered exhaust to determine if continuous compliant sampling is required. Because potential (unfiltered) emissions are not measured, methods have been developed to estimate these emissions. One of the methods accepted by the Environmental Protection Agency is the measurement of the accumulation of radionuclides on the HEPA filters. Nondestructive assay (NDA) was selected for determining the accumulation on the HEPA filters. NDA was performed on the HEPA filters before and after a campaign in 1997. NDA results indicate that 2.1 E+4 becquerels of cesium-137 were accumulated on the primary HEPA 1700 filter during the campaign. The feed material processed in the campaign contained a total of 1.4 E+l6 Bq of cesium-137. The release factor for the evaporator process is 1.5 E-12. …
Date: July 6, 1998
Creator: Johnson, R. E.
System: The UNT Digital Library
Waste processing air cleaning (open access)

Waste processing air cleaning

Waste processing and preparing waste to support waste processing relies heavily on ventilation. Ventilation is used at the Hanford Site on the waste storage tanks to provide confinement, cooling, and removal of flammable gases.
Date: July 27, 1998
Creator: Kriskovich, J. R.
System: The UNT Digital Library
ATI TDA 5A aerosol generator evaluation (open access)

ATI TDA 5A aerosol generator evaluation

Oil based aerosol ``Smoke`` commonly used for testing the efficiency and penetration of High Efficiency Particulate Air filters (HEPA) and HEPA systems can produce flammability hazards that may not have been previously considered. A combustion incident involving an aerosol generator has caused an investigation into the hazards of the aerosol used to test HEPA systems at Hanford.
Date: July 27, 1998
Creator: Gilles, D. A.
System: The UNT Digital Library
Improved HEPA Filter Technology for Flexible and Rigid Containment Barriers (open access)

Improved HEPA Filter Technology for Flexible and Rigid Containment Barriers

Safety and reliability in glovebox operations can be significantly improved and waste packaging efficiencies can be increased by inserting flexible, lightweight, high capacity HEPA filters into the walls of plastic sheet barriers. This HEPA filter/barrier technology can be adapted to a wide variety of applications: disposable waste bags, protective environmental barriers for electronic equipment, single or multiple use glovebag assemblies, flexible glovebox wall elements, and room partitions. These reliable and inexpensive filtered barriers have many uses in fields such as radioactive waste processing, HVAC filter changeout, vapor or grit blasting, asbestos cleanup, pharmaceutical, medical, biological, and electronic equipment containment. The applications can result in significant cost savings, improved operational reliability and safety, and total waste volume reduction. This technology was developed at the Argonne National Laboratory-West (ANL-W) in 1993 and has been used at ANL-W since then at the TRU Waste Characterization Chamber Gloveboxes. Another 1998 AGS Conference paper titled "TRU Waste Characterization Gloveboxes", presented by Mr. David Duncan of ANL-W, describes these boxes.
Date: July 1, 1998
Creator: Pinson, Paul Arthur
System: The UNT Digital Library
Generation of Subpicosecond X-ray Pulses Using RF OrbitDeflection (open access)

Generation of Subpicosecond X-ray Pulses Using RF OrbitDeflection

None
Date: July 1, 1998
Creator: Zholents, A.; Heimann, P.; Zolotorev, M. & Byrd, J.
System: The UNT Digital Library
Improved HEPA Filter Technology for Flexible and Rigid Containment Barriers (open access)

Improved HEPA Filter Technology for Flexible and Rigid Containment Barriers

Safety and reliability in glovebox operations can be significantly improved and waste packaging efficiencies can be increased by inserting flexible, lightweight, high capacity HEPA filters into the walls of plastic sheet barriers. This HEPA filter/barrier technology can be adapted to a wide variety of applications: disposable waste bags, protective environmental barriers for electronic equipment, single or multiple use glovebag assemblies, flexible glovebox wall elements, and room partitions. These reliable and inexpensive filtered barriers have many uses in fields such as radioactive waste processing, HVAC filter changeout, vapor or grit blasting, asbestos cleanup, pharmaceutical, medical, biological, and electronic equipment containment. The applications can result in significant cost savings, improved operational reliability and safety, and total waste volume reduction. This technology was developed at the Argonne National Laboratory-West (ANL-W) in 1993 and has been used at ANL-W since then at the TRU Waste Characterization Chamber Gloveboxes. Another 1998 AGS Conference paper titled "TRU Waste Characterization Gloveboxes", presented by Mr. David Duncan of ANL-W, describes these boxes.
Date: July 1, 1998
Creator: Pinson, P. A.
System: The UNT Digital Library
Cosmological moduli problem in a supersymmetric model with direct gauge mediation (open access)

Cosmological moduli problem in a supersymmetric model with direct gauge mediation

Recently, an interesting class of the direct gauge mediation supersymmetry (SUSY) breaking models are proposed, in which the minimum of the potential of the SUSY breaking field is determined by the inverted hierarchy mechanism. We consider their cosmological implications. In this class of models, SUSY breaking field has a very flat potential, which may have a cosmological importance. Assuming the initial amplitude of the SUSY breaking field to be of the order of the Planck scale, it can be a source of a large entropy production. A special attention is paid to the cosmological moduli problem, and we will see the cosmological mass density of the moduli field can be significantly reduced.
Date: July 7, 1998
Creator: Moroi, Takeo
System: The UNT Digital Library
An Apparatus for the Measurement of Various Scattering Processes in Intermediate Energy, Ion - Atom Collisions (open access)

An Apparatus for the Measurement of Various Scattering Processes in Intermediate Energy, Ion - Atom Collisions

This paper summarizes the main features of an apparatus constructed at the University of Toledo for the study of various scattering processes in intermediate energy, ion - atom collisions. The main purpose of this facility is to provide experimental data which serve as benchmarks to test current scattering theories for those processes. Recent measurements of single electron detachment (SED) and double electron detachment (DED) total cross sections for 5-50 keV H{sup -} ions incident on noble gases and for 10-50 keV H{sup -} ions incident on CH{sub 4} molecules were conducted in this laboratory. As a result of an analysis of the scattered beam growth curves, information about other charge-changing cross sections in the hydrogen-atom (molecule) collision systems were obtain, as well.
Date: July 1, 1998
Creator: Kvale, T. J. & Seely, D. G.
System: The UNT Digital Library
Isotope constraints on the involvement of fluids in the San Andreas Fault System, California (open access)

Isotope constraints on the involvement of fluids in the San Andreas Fault System, California

Fluids are suspected to play a major role in earthquake mechanics, especially in the case of the weak San Andreas Fault (SAF). Models developed to explain the weakness of the fault are similar but rely on different fluid sources. A recent study of groundwaters associated with the SAF has provided evidence for a geopressured mantle fluid source (Kennedy et al., 1997). We present here an isotope study comparing deformation zones (gouges, breccias, fault veins, slickensides, cataclasites), and vein fillings with their hosts and the fluids associated with these materials, as sampled by fluid inclusions. We are investigating ca. 250 samples from over 20 localities along the San Andreas and adjacent faults from South San Francisco to East Los Angeles. Samples from the exhumed San Gabriel Fault, a deeper equivalent of the SAF, are included as well as samples from the Santa Ynez Fault, another former strand of the SAF embedded in Miocene limestones. All the major lithologies (granites, gneisses, sandstones, limestones, marbles and serpentinites) have been sampled for isotope analyses of C, O, H, He, Ne, Ar, Sr, Nd, and Pb.
Date: July 1, 1998
Creator: Pili, E.; Kennedy, B. M.; Conrad, S. M.; Gratier, J. -P. & Poitrasson, F.
System: The UNT Digital Library
PC and monitor night status: Power management enabling and manual turn-off (open access)

PC and monitor night status: Power management enabling and manual turn-off

While office equipment accounts for about 7 percent of commercial building energy use, this reflects considerable energy savings from the use of automatic power management. Most of these savings were gained through the use of low-power modes that meet the criteria of the U.S. EPA's Energy Star program. Despite this success, there are large amounts of additional savings that could be gained if all equipment capable of power management use were enabled and functioning. A considerable portion of equipment is not enabled for power management at all, enabled only partially, or is enabled but prevented from functioning. Additional savings could be gained if more equipment were turned off at night manually. We compiled results from 17 studies from the office equipment literature addressing PCs and monitors. Some factors important for annual energy use, such as power levels, have been documented elsewhere and are not covered. We review methods for estimating office equipment use patterns and energy use, and present findings on night status--power management and manual turn-off rates. In early studies, PC power management was often found to function in 25 percent or less of the Energy Star compliant units (10 percent of all PCs). However, recent assessments have found …
Date: July 30, 1998
Creator: Nordman, Bruce; Meier, Alan & Piette, Mary Ann
System: The UNT Digital Library
Environmental Management Science Program Workshop (open access)

Environmental Management Science Program Workshop

This program summary book is a compendium of project summaries submitted by principal investigators in the Environmental Management Science Program and Environmental Management/Energy Research Pilot Collaborative Research Program (Wolf-Broido Program). These summaries provide information about the most recent project activities and accomplishments. All projects will be represented at the workshop poster sessions, so you will have an opportunity to meet with the researchers. The projects will be presented in the same order at the poster session as they are presented in this summary book. Detailed questions about an individual project may be directed to the investigators involved.
Date: July 1, 1998
Creator: unknown
System: The UNT Digital Library
Progress on the relativistic klystron two-beam accelerator prototype (open access)

Progress on the relativistic klystron two-beam accelerator prototype

The technical challenge for making two-beam accelerators into realizable power sources lies in the creation of the drive beam and in its propagation over long distances through multiple extraction sections. This year we have been constructing a 1.2-kA, l-MeV, electron induction prototype injector as a collaborative effort between LBL and LLNL. The electron source will be a 3.5"-diameter, thermionic, flat-surface cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 120-ns flat top (1% energy variation), and a normalized edge emittance of less than 200 {pi}-mm-mr. Planned diagnostics include an isolated cathode with resistive divider for direct measurement of current emission, resistive-wall and magnetic probe current monitors for measuring beam current and centroid position, capacitive probes for measuring A-K gap voltage, an energy spectrometer, and a pepper-pot emittance diagnostic. Details of the injector, beam line, and diagnostics are presented.
Date: July 5, 1998
Creator: Anderson, D. E.; Eylon, S.; Henestroza, E.; Houck, T. L.; Lidia, S. M.; Vanecek, D. L. et al.
System: The UNT Digital Library
Interface Characterization Techniques for 304L Stainless Steel Resistance Upset Welds (open access)

Interface Characterization Techniques for 304L Stainless Steel Resistance Upset Welds

In an effort to better characterize and classify austenitic stainless steel resistance upset welds, standard methods have been examined and alternative methods investigated. Optical microscopy yields subjective classification due to deformation obscured bond lines and individual perception. The use of specimen preparations that better reveal grain boundaries aids in substantiating optical information. Electron microscopy techniques produce quantitative information in relation to microstructural constituents. Orientation Imaging Microscopy (OIM) is a relatively new technique for obtaining objective, quantitative information pertaining to weld integrity, i.e., percent grain boundary growth across the interface.
Date: July 26, 1998
Creator: Abeln, Terri G.; Kackenko, E. Jim; Necker, Carl T. & Field, Robert D.
System: The UNT Digital Library
Terawatt Picosecond CO(sub 2) Laser Technology for High Energy Physics Applications (open access)

Terawatt Picosecond CO(sub 2) Laser Technology for High Energy Physics Applications

Demonstration of ultra-high acceleration gradients in the SM LWFA experiments put a next objective for the laser accelerator development to achieve a low-emittance monochromatic acceleration over extended interaction distances. The emerging picosecond terawatt (ps-TW) CO{sub 2} laser technology helps to meet this strategic goal. Among the considered examples are: the staged electron laser accelerator (STELLA) experiment, which is being conducted at the Brookhaven ATF, and the plasma-channeled LWFA. The long-wavelength and high average power capabilities of CO{sub 2} lasers maybe utilized also for generation of intense x-ray and gamma radiation through Compton back-scattering of the laser beams off relativistic electrons. We discuss applications of ps-TW CO{sub 2} lasers for a tentative {gamma}-{gamma} (or {gamma}-lepton) collider and generation of polarized positron beams.
Date: July 5, 1998
Creator: Pogorelsky, I. V.
System: The UNT Digital Library
STELLA Experiment - Microbunch Diagnostic (open access)

STELLA Experiment - Microbunch Diagnostic

A microbunch diagnostic system is built at the Accelerator Test Facility (ATF) of Brookhaven National Laboratory for monitoring microbunches (10-fs bunch length) produced by the Inverse Free Electron Laser accelerator in Staged Electron Laser Acceleration experiment. It is similar to one already demonstrated at the ATF. With greatly improved beam optics conditions higher order harmonic coherent transition radiation will be measurable to determine the microbunch length and shape.
Date: July 1998
Creator: He, P.; Liu, Y.; Cline, D. B.; Babzien, M.; Gallardo, J. C.; Kusche, K. P. et al.
System: The UNT Digital Library
Excitations and Optical Properties of Phenylene Based Polymers (open access)

Excitations and Optical Properties of Phenylene Based Polymers

A complex picture of phenylene-based polymers is developed which unifies features of band and molecular exciton models. It incorporates major experimental finding in direct, and photoinduced optical absorption, stimulated photoemission and photoconductivity. The authors give new assignments for the most disputed features and identify new ones as edge states. The authors confirm a low binding energy for the principle emitting exciton and show that it dominates also in the fundamental absorption. Contradictions in the current modeling state-of-art are displayed and discussed.
Date: July 1, 1998
Creator: Kirova, N.; Brazovskii, S.; Bishop, A. R.; McBranch, D. & Klimov, V.
System: The UNT Digital Library
Generalized Multi-Edge Analysis for K-Edge Densitometry (open access)

Generalized Multi-Edge Analysis for K-Edge Densitometry

In K-edge densitometry (KED), a continuous-energy x-ray beam is transmitted through a liquid sample. The actinide content of the sample can be measured through analysis of the transmitted portion of the x-ray beam. Traditional methods for KED analysis allow the simultaneous calculation of, at most, two actinide concentrations. A generalized multi-edge KED analytical method is presented, allowing up to six actinide concentrations to be calculated simultaneously. Applications of this method for hybrid KED/x-ray fluorescence (HKED) systems are discussed. Current HKED systems require the operator to know the approximate actinide content of each sample, and manually select the proper analysis mode. The new multi-edge KED technique allows rapid identification of the major actinide components in a sample, independent of actinide content. The proper HKED analysis mode can be selected automatically, without requiring sample content information from the user. Automatic HKED analysis would be especially useful in an analytical laboratory setting, where samples with truly unknown characteristics are encountered. Because this technique requires no hardware modifications, several facilities that use HKED may eventually benefit from this approach.
Date: July 26, 1998
Creator: Collins, M.
System: The UNT Digital Library
Geochemical Methods for the Identification of ASR Gel (open access)

Geochemical Methods for the Identification of ASR Gel

This paper presents a geochemical method for staining various products of the alkali-silica reaction. The method is based on both the composition of ASR gel and one of its properties (the ability to exchange cations with a fluid). The stained concrete can be observed in normal light and serves as both a rapid field screening method and a useful aid for detailed petrographic examinations.
Date: July 1, 1998
Creator: Guthrie, G. D. & Carey, J. W.
System: The UNT Digital Library
Matrix Characterization of Plutonium Residues by Alpha-Particle Self-Interrogation (open access)

Matrix Characterization of Plutonium Residues by Alpha-Particle Self-Interrogation

Legacy plutonium residues often have inadequate item descriptions. Nondestructive characterization can help segregate these items for reprocessing or provide information needed for disposal or storage. Alpha particle-induced gamma-ray spectra contain a wealth of information that can be used for matrix characterization. We demonstrate how this information can be used for item identification. Gamma-ray spectra were recorded at the Los Alamos Plutonium Facility from a variety of legacy, plutonium-processing residues and product materials. The comparison and analysis of these spectra are presented.
Date: July 26, 1998
Creator: Prettyman, T.H.; Foster, L.A. & Staples, P.
System: The UNT Digital Library
Measuring advances in HVAC distribution system designs (open access)

Measuring advances in HVAC distribution system designs

Substantial commercial building energy savings have been achieved by improving the performance of the HVAC distribution system. The energy savings result from distribution system design improvements, advanced control capabilities, and use of variable-speed motors. Yet, much of the commercial building stock remains equipped with inefficient systems. Contributing to this is the absence of a definition for distribution system efficiency as well as the analysis methods for quantifying performance. This research investigates the application of performance indices to assess design advancements in commercial building thermal distribution systems. The index definitions are based on a first and second law of thermodynamics analysis of the system. The second law or availability analysis enables the determination of the true efficiency of the system. Availability analysis is a convenient way to make system efficiency comparisons since performance is evaluated relative to an ideal process. A TRNSYS simulation model is developed to analyze the performance of two distribution system types, a constant air volume system and a variable air volume system, that serve one floor of a large office building. Performance indices are calculated using the simulation results to compare the performance of the two systems types in several locations. Changes in index values are compared …
Date: July 1, 1998
Creator: Franconi, Ellen
System: The UNT Digital Library
Reverse Engineering Using Computed Tomography (open access)

Reverse Engineering Using Computed Tomography

None
Date: July 19, 1998
Creator: Kelley, T. A.; Hefele, J. & Stupin, D. M.
System: The UNT Digital Library