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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
Giving effective poster presentations (open access)

Giving effective poster presentations

Giving an effective poster presentation can be easy and rewarding with attention to a few proven concepts. Define your audience. Keep the words and graphics clear, concise, and eye-catching. Remember, you have three seconds to attract attention and 30 seconds to get your message across.
Date: August 27, 1998
Creator: Rice, J A
System: The UNT Digital Library
The dimensional stability of lightly-loaded epoxy joints (open access)

The dimensional stability of lightly-loaded epoxy joints

The use of adhesives to bond metal mounting structures to optical components can significantly simplify the design of an optical system. In precision applications, dimensional instability of the adhesive must be included as a component of the overall error budget. This paper describes the qualification testing of a balanced heterodyne interferometer system in a carefully controlled environment for the purpose of measuring joint stability. Results of this qualification test are reported.
Date: August 27, 1998
Creator: Badami, V G; Lawton, K M; Patterson, S R & Tajbakhsh, H
System: The UNT Digital Library
Fatigue crack initiation in carbon and low-alloy steels in light water reactor environments : mechanism and prediction. (open access)

Fatigue crack initiation in carbon and low-alloy steels in light water reactor environments : mechanism and prediction.

Section 111 of the ASME Boiler and Pressure Vessel Code specifies fatigue design curves for structural materials. The effects of reactor coolant environments are not explicitly addressed by the Code design curves. Recent test data illustrate potentially significant effects of light water reactor (LWR) coolant environments on the fatigue resistance of carbon and low-alloy steels. Under certain loading and environmental conditions, fatigue lives of test specimens may be shorter than those in air by a factor of {approx}70. The crack initiation and crack growth characteristics of carbon and low-alloy steels in LWR environments are presented. Decreases in fatigue life of these steels in high-dissolved-oxygen water are caused primarily by the effect of environment on growth of short cracks < 100 {micro}m in depth. The material and loading parameters that influence fatigue life in LWR environments are defined. Fatigue life is decreased significantly when five conditions are satisfied simultaneously, viz., applied strain range, service temperature, dissolved oxygen in water, and S content in steel are above a threshold level, and loading strain rate is below a threshold value. Statistical models have been developed for estimating the fatigue life of these steels in LWR environments. The significance of the effect of environment …
Date: January 27, 1998
Creator: Chopra, O. K. & Shack, W. J.
System: The UNT Digital Library
First-principles calculation of atomic structure and electrochemical potential of Li{sub 1+x}V{sub 3}O{sub 8}. (open access)

First-principles calculation of atomic structure and electrochemical potential of Li{sub 1+x}V{sub 3}O{sub 8}.

Interest in the {gamma}-bronze, Li{sub 1+x}V{sub 3}O{sub g}, as a possible electrode material in rechargeable Li batteries has stimulated several experimental studies on this system. Detailed interpretation of the electrochemical and physical-property measurements is complicated by uncertainties regarding the structural arrangement of Li atoms as a function of x and by a phase transition between two monoclinic structures ({gamma}{sub a}, {gamma}{sub b}) during intercalation. To elucidate the atomic structures and the phase transition, first-principles calculations are performed with the local-density-functional-theory (LDFT) planewave pseudopotential method for both {gamma}{sub a} and {gamma}{sub b}, as a function of lithiation. Calculations for the compositions 1 + x = 1.5 and 1 + x = 4 confirm that the Li configuration determined in the existing x-ray diffraction structure refinements (at 1 + x = 1.2 and 1 + x = 4 respectively), coincide with the predicted low-energy configurations. Structure predictions were made at intermediate compositions, for which no experimental structure measurement is available. The order in which the tetrahedrally coordinated Li sites are filled at equilibrium as a function of x in {gamma}{sub a}, was predicted. Calculated electrochemical potentials as a function of composition agree well with experimental data.
Date: August 27, 1998
Creator: Benedek, R.
System: The UNT Digital Library
Waveguide harmonic damper for klystron amplifier. (open access)

Waveguide harmonic damper for klystron amplifier.

A waveguide harmonic damper was designed for removing the harmonic frequency power from the klystron amplifiers of the APS linac. Straight coaxial probe antennas are used in a rectangular waveguide to form a damper. A linear array of the probe antennas is used on a narrow wall of the rectangular waveguide for damping klystron harmonics while decoupling the fundamental frequency in dominent TE{sub 01} mode. The klystron harmonics can exist in the waveguide as waveguide higher-order modes above cutoff. Computer simulations are made to investigate the waveguide harmonic damping characteristics of the damper.
Date: October 27, 1998
Creator: Kang, Y.
System: The UNT Digital Library
Simulation and measurement of the electrostatic beam kicker in the low-energy undulator test line. (open access)

Simulation and measurement of the electrostatic beam kicker in the low-energy undulator test line.

An electrostatic kicker has been constructed for use in the Low-Energy Undulator Test Line (LEUTL) at the Advanced Photon Source (APS). The function of the kicker is to limit the amount of beam current to be accelerated by the APS linac. Two electrodes within the kicker create an electric field that adjusts the trajectory of the beam. This paper will explore the static fields that are set up between the offset electrode plates and determine the reaction of the beam to this field. The kicker was numerically simulated using the electromagnetic solver package MAFIA [1].
Date: October 27, 1998
Creator: Waldschmidt, G. J.
System: The UNT Digital Library
Mechanical and electrical properties of ZnO/Ag nanocomposites. (open access)

Mechanical and electrical properties of ZnO/Ag nanocomposites.

Effects of Ag particle dispersions on microstructural development and some properties were investigated for ZnO/Ag nanocomposites. They were fabricated by Pulse Electric Current Sintering (PECS) Process to achieve finer and densified microstructure. ZnO/Ag nanocomposites with novel microstructure which were prepared by a reduction process using Ag{sub 2}O fine powders were compared with microcomposites prepared by mixing of Ag and ZnO powders. SEM observation indicated that fine Ag particles were homogeneously dispersed within the ZnO matrix grains and at the grain boundaries for ZnO/Ag nanocomposites prepared by the reduction process using Ag{sub 2}O fine powder. Hardness and fracture toughness increased with increasing the Ag volume fraction. Linear resistivity was decreased with increasing Ag volume fraction. However, the mechanical and electrical properties appeared to the significantly different for composites prepared by two different powder processes.
Date: August 27, 1998
Creator: Hayashi, Y.
System: The UNT Digital Library
Wavelet Compression of Complex SAR Imagery Using Complex- and Real-Valued Wavelets: A Comparative Study (open access)

Wavelet Compression of Complex SAR Imagery Using Complex- and Real-Valued Wavelets: A Comparative Study

While many synthetic aperture radar (SAR) applications use only detected imagery, dramatic improvements in resolution and employment of algorithms requiring complex-valued SAR imagery suggest the need for compression of complex data. Here, we investigate the benefits of using complex- valued wavelets on complex SAR imagery in the embedded zerotree wavelet compression algorithm, compared to using real-valued wavelets applied separately to the real and imaginary components. This compression is applied at low ratios (4:1-12:1) for high fidelity output. The complex spatial correlation metric is used to numerically evaluate quality. Numerical results are tabulated and original and decompressed imagery are presented as well as correlation maps to allow visual comparisons.
Date: October 27, 1998
Creator: Ives, R. W.; Kiser, C. & Magotra, N.
System: The UNT Digital Library
Characterizing transverse beam dynamics at the APS storage ring using a dual-sweep streak camera. (open access)

Characterizing transverse beam dynamics at the APS storage ring using a dual-sweep streak camera.

We present a novel technique for characterizing transverse beam dynamics using a dual-sweep streak camera. The camera is used to record the front view of successive beam bunches and/or successive turns of the bunches. This extension of the dual-sweep technique makes it possible to display non-repeatable beam transverse motion in two fast and slow time scales of choice, and in a single shot. We present a study of a transverse multi-bunch instability in the APS storage ring. The positions, sizes, and shapes of 20 bunches (2.84 ns apart) in the train, in 3 to 14 successive turns (3.68 {micro}s apart) are recorded in a single image, providing rich information about the unstable beam. These include the amplitude of the oscillation ({approximately}0.0 at the head of the train and {approximately}2 mm towards the end of the train), the bunch-to-bunch phase difference, and the significant transverse size growth within the train. In the second example, the technique is used to characterize the injection-kicker induced beam motion, in support of the planned storage ring top-up operation. By adjusting the time scale of the dual sweep, it clearly shows the amplitude ({+-}1.8mm) and direction of the kick, and the subsequent decoherence ({approximately} 500 turns) …
Date: May 27, 1998
Creator: Yang, B.
System: The UNT Digital Library
Removal of heavy metals from aqueous waste streams using surface-modified nanosized TiO{sub 2} photocatalysts. (open access)

Removal of heavy metals from aqueous waste streams using surface-modified nanosized TiO{sub 2} photocatalysts.

Titanium dioxide (TiO{sub 2}) colloidal particles ({approximately}45{angstrom}) whose surfaces were modified with chelating agents for photocatalytic removal of heavy-metal ions and their subsequent reduction to metallic form were investigated. Experiments were performed on nanoparticle TiO{sub 2} colloids derivatized with bidentate and tridentate ligands (thiolactic acid [TLA], cysteine, and alanine [ALA]) in batch mode in a photoreactor with 254nm light. We used catalysts designed and synthesized for selective and efficient removal of Pb and Cu with and without added hole scavenger (methanol). Parallel experiments also have been carried out in the dark to study metal ion adsorption properties. Solutions have been filtered to remove TiO{sub 2}, and metal particulates. Both the native solution and the metal deposited on the nanocrystalline TiO{sub 2} particles were analyzed. Results demonstrate that for the case of lead, the most effective TiO{sub 2} surface modifier was TLA (>99% Pb(II) removed from solution). Experiments performed to study Cn removal using TiO{sub 2} colloids modified with alanine showed that copper ions were effectively removed and reduced to metallic form in the presence of methanol.
Date: August 27, 1998
Creator: Meshkov, N. K.
System: The UNT Digital Library
Fluid transfer concentration of airborne radioxenon to enhance monitoring capabilities. (open access)

Fluid transfer concentration of airborne radioxenon to enhance monitoring capabilities.

To facilitate airborne radioxenon monitoring, a xenon concentration method with potential advantages over current technology in simplicity, size, and cost has been developed. The concentration technique is based on the preferential absorption of heavy noble gases (krypton, xenon, and radon) by certain organic fluids. To implement this concentration technique, a radioxenon monitoring system requires three integrated sub-systems: (1) an absorption sub-system; (2) a degassing sub-system; and (3) a radiation detection sub-system. This study is focused on the characterization and optimization of the first two sub-systems. Measurements using a small prototype absorption tower have indicated a xenon removal factor of approximately 50% and the specific concentration at saturation of certain organic fluids to be about 2.5 times the specific concentration in the sampled air. Various techniques for degassing have been investigated, including heating, purging, agitation and vacuum. Ultrasonic agitation of a thin film in a strong vacuum has been shown to be an effective means of degassing the transfer fluid continuously. Various schemes for integrating all of the sub-systems are considered. Combining the small prototype absorption and degassing sub-systems should result in a transfer efficiency of about 33% and a single stage concentration factor of about 6.7.
Date: May 27, 1998
Creator: Russ, W. R.
System: The UNT Digital Library
Incident spectrum determination for time-of-flight neutron powder diffraction data analysis. (open access)

Incident spectrum determination for time-of-flight neutron powder diffraction data analysis.

Accurate characterization of the incident neutron spectrum is an important requirement for precise Rietveld analysis of time-of-flight powder neutron diffraction data. Without an accurate incident spectrum the calculated model for the measured relative intensities of individual Bragg reflections will possess systematic errors. We describe a method for obtaining an accurate numerical incident spectrum using data from a transmitted beam monitor.
Date: August 27, 1998
Creator: Hodges, J. P.
System: The UNT Digital Library
Three-degree-of-freedom optic mount for extreme ultraviolet lithography (open access)

Three-degree-of-freedom optic mount for extreme ultraviolet lithography

A mechanism to finely align optics for extreme ultraviolet lithography applications is presented. The mechanism is a small motion parallel link manipulator with flexure joints that exhibits nanometer level positioning capability. Performance results of a prototype system are given in this paper.
Date: August 27, 1998
Creator: Hale, L.; Jensen, S.; Malsbury, T.; Parker, J. & Tajbakhsh, H.
System: The UNT Digital Library
Development of a Radiative-Hydrodynamics Testbed Using the Petawatt Laser Facility (open access)

Development of a Radiative-Hydrodynamics Testbed Using the Petawatt Laser Facility

Many of the conditions believed to underlie astrophysical phenomena have been difficult to achieve in a laboratory setting. For example, models of supernova remnant evolution rely on a detailed understanding of the propagation of shock waves with gigabar pressures at temperatures of 1 keV or more where radiative effects can be important. Current models of gamma ray bursts posit a relativistically expanding plasma fireball with copious production of electron-positron pairs, a difficult scenario to experimentally verify. However, a new class of lasers, such as the Petawatt laser,Perry 1996 are capable of producing focused intensities greater than 10<sup>20</sup> W/cm&sup2; where such relativistic effects can be observed and even dominate the laser-target interaction. There is ample evidence in observational data from supernova remnants of the aftermath of the passage of radiative shock or blast waves. In the early phases of supernova remnant evolution, the radially-expanding shock wave expands nearly adiabatically since it is traveling at a very high velocity as it begins to sweep up the surrounding interstellar gas. A Sedov-Taylor blast wave solution can be applied to this phase,Taylor 1950, Sedov 1959 when the mass of interstellar gas swept up by the blast greatly exceeds the mass of the stellar ejecta, …
Date: August 27, 1998
Creator: Koch, J. A.; Bell, P. M.; Brown, C.; Budil, K. S.; Estabrook, K. G.; Gold, D. M. et al.
System: The UNT Digital Library
Safety and environmental process for the design and construction of the National Ignition Facility (open access)

Safety and environmental process for the design and construction of the National Ignition Facility

The National Ignition Facility (NIF) is a U.S. Department of Energy (DOE) laser fusion experimental facility currently under construction at the Lawrence Livermore National Laboratory (LLNL). This paper describes the safety and environmental processes followed by NIF during the design and construction activities.
Date: May 27, 1998
Creator: Brereton, S.J., LLNL
System: The UNT Digital Library
Use of alternating-Z doubling in high-dynamic-range tripling: design and evaluation of an optimized prototype tripler (open access)

Use of alternating-Z doubling in high-dynamic-range tripling: design and evaluation of an optimized prototype tripler

We designed and tested an alternating-Z tripler that consisted of two detuned, Type-1, potassium dihydrogen phosphate (KD*P) doublers and one KD*P mixer. The crystal thicknesses were, respectively, 13, 10 and 10 mm, and the detunings of the doublers were +420 and -520 µrad. All three crystals were fabricated from 80% deuterated KDP. Conversion efficiency was measured and calculated for input 1053- nm pulses with approximately rectangular waveforms and durations of either 1 or 6 ns, and for 20-ns pulses that exhibited intensity variation by a factor of 10. The measured peak conversion efficiency was more than 80%, and energy conversion efficiencies ranged from 62-80% depending on the waveform of the input pulse. The expected large dynamic range in input intensity, 9-10, was observed, and the measured and calculated efficiencies were in excellent agreement.
Date: July 27, 1998
Creator: Auerbach, J. M.; Barker, C.; Eimerl, D.; Milan, D. & Milonni, P. W.
System: The UNT Digital Library
Integration of complex-wide mixed low-level waste activities for program acceleration and optimization (open access)

Integration of complex-wide mixed low-level waste activities for program acceleration and optimization

In July 1996, the US Department of Energy (DOE) chartered a contractor-led effort to develop a suite of technically defensible, integrated alternatives which would allow the Environmental Management program to accomplish its mission objectives in an accelerated fashion and at a reduced cost. These alternatives, or opportunities, could then be evaluated by DOE and stakeholders for possible implementation, given precursor requirements (regulatory changes, etc.) could be met and benefits to the Complex realized. This contractor effort initially focused on six waste types, one of which was Mixed Low-Level Waste (MLLW). Many opportunities were identified by the contractor team for integrating MLLW activities across the DOE Complex. These opportunities were further narrowed to six that had the most promise for implementation and savings to the DOE Complex. The opportunities include six items: (1) the consolidation of individual site analytical services procurement efforts, (2) the consolidation of individual site MLLW treatment services procurement efforts, (3) establishment of ``de minimus`` radioactivity levels, (4) standardization of characterization requirements, (5) increased utilization of existing DOE treatment facilities, and (6) using a combination of DOE and commercial MLLW disposal capacity. The results of the integration effort showed that by managing MLLW activities across the DOE Complex …
Date: January 27, 1998
Creator: McKenney, D. E.
System: The UNT Digital Library
Effect of crossed beams irradiation on parametric instabilities (open access)

Effect of crossed beams irradiation on parametric instabilities

Modification of the growth of scattering processes in the case of multiple beam irradiation compared to single beam irradiation has been investigated in a preformed plasma using Thomson scattrering of a short wavelength probe beam, and spectral and temporal analysis of reflected and transmitted light. First observations of the reduction of the amplitude of ion acoustic waves associated with stimulated Brillouin scattering, amplification of the amplitude of electron plasma waves associated with stimulated Raman scattering, and transfer of energy between crqssing beams with same frequency in a flowing plasma under crossed beam irradiation are reported.
Date: April 27, 1998
Creator: Labaune, C., Ecole Polytechnique, France
System: The UNT Digital Library
EOS for critical slurry and solution systems (open access)

EOS for critical slurry and solution systems

In a fire involving fissile material, the mixture of the fissile material ash with fire fighting water may lead to a criticality excursion if there are nearby sumps that permit a critical geometry. The severity of the resulting energy release and pressure pulse is dependent on the rate at which the mixing occurs. To calculate these excursions, a non-equilibrium equation of state for the water ash mixture or slurry is needed that accounts for the thermal non-equilibrium that occurs due to finite heat transfer rates. We are developing the slurry EOS as well as a lumped neutronic and hydrodynamic model to serve as a testing ground for the non-equilibrium EOS before its incorporation into more sophisticated neutronic-hydrodynamics codes. Though the model lacks spatial dependence, it provides estimates of energy release and pressure pulses for various mixture assembly rates. We are also developing a non-equilibrium EOS for critical solution systems in which the fissile material is dissolved in water, which accounts for chemical non-equilibrium due to finite mass transfer rates. In contrast to previously published solution EOS, our solution EOS specifically accounts for mass diffusion of dissolved radiolytic gas to bubble nucleation sites. This EOS was developed to check our overall …
Date: October 27, 1998
Creator: DiPeso, G & Peterson, P
System: The UNT Digital Library
U.S. transparency monitoring of HEU oxide conversion and blending to LEU hexafluoride at three Russian blending plants (open access)

U.S. transparency monitoring of HEU oxide conversion and blending to LEU hexafluoride at three Russian blending plants

The down-blending of Russian highly enriched uranium (HEU) takes place at three Russian gaseous centrifuge enrichment plants. The fluorination of HEU oxide and down-blending of HEU hexafluoride began in 1994, and shipments of low enriched uranium (LEU) hexafluoride product to the United States Enrichment Corporation (USEC) began in 1995 US transparency monitoring under the HEU Purchase Agreement began in 1996 and includes a permanent monitoring presence US transparency monitoring at these facilities is intended to provide confidence that HEU is received and down-blended to LEU for shipment to USEC The monitoring begins with observation of the receipt of HEU oxide shipments, including confirmation of enrichment using US nondestructive assay equipment The feeding of HEU oxide to the fluorination process and the withdrawal of HEU hexafluoride are monitored Monitoring is also conducted where the blending takes place and where shipping cylinders are filled with LEU product. A series of process and material accountancy documents are provided to US monitors.
Date: July 27, 1998
Creator: Leich, D.
System: The UNT Digital Library
Decommissioning plan for the National Ignition Facility (open access)

Decommissioning plan for the National Ignition Facility

The National Ignition Facility (NIF) is a US Department of Energy inertial confinement laser fusion experimental facility currently under construction at the Lawrence Livermore National Laboratory (LLNL). To ensure that decontamination and decommissioning (D&D) issues at the end-of-life are manageable, this subject has received attention from an early stage. This paper summarizes the NIF D&D issues, and the status of the D&D plan.
Date: May 27, 1998
Creator: Brereton, S.
System: The UNT Digital Library
Efficient computation of periodic and nonperiodic Green`s functions in layered media using the MPIE (open access)

Efficient computation of periodic and nonperiodic Green`s functions in layered media using the MPIE

The mixed potential integral equation (MPIE) formulation is convenient for problems involving layered media because potential quantities involve low order singularities, in comparison to field quantities. For nonperiodic problems, the associated Green`s potentials involve spectral integrals of the Sommerfeld type, in the periodic case, discrete sums over sampled values of the same spectra are required. When source and observation points are in the same or in adjacent layers, the convergence of both representations is enhanced by isolating the direct and quasi-static image contributions associated with the nearby layers. In the periodic case, the convergence of direct and image contributions may be rapidly accelerated by means of the Ewadd method.
Date: March 27, 1998
Creator: Wilton, D. R.; Jackson, D. R. & Champagne, N. J.
System: The UNT Digital Library