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Solar Radiation Data Sets: Solar Resource Assessment Workshop (open access)

Solar Radiation Data Sets: Solar Resource Assessment Workshop

None
Date: October 29, 2008
Creator: Wilcox, S.; George, R. & Myers, D.
Object Type: Article
System: The UNT Digital Library
Recalibration of H Canyon Online Spectrophotometer at Extended Uranium Concentration (open access)

Recalibration of H Canyon Online Spectrophotometer at Extended Uranium Concentration

The H Canyon online spectrophotometers are calibrated for measurement of the uranium and nitric acid concentrations of several tanks in the 2nd Uranium Cycle.[1] The spectrometers, flow cells, and prediction models are currently optimized for a process in which uranium concentrations are expected to range from 0-15 g/L and nitric acid concentrations from 0.05-6 M. However, an upcoming processing campaign will involve 'Super Kukla' material, which has a lower than usual enrichment of fissionable uranium. Total uranium concentrations will be higher, spanning approximately 0-30 g/L U, with no change in the nitric acid concentrations. The new processing conditions require the installation of new flow cells with shorter path lengths. As the process solutions have a higher uranium concentration, the shorter path length is required to decrease the absorptivity to values closer to the optimal range for the instrument. Also, new uranium and nitric acid prediction models are required to span the extended uranium concentration range. The models will be developed for the 17.5 and 15.4 tanks, for which nitric acid concentrations will not exceed 1 M. The restricted acid range compared to the original models is anticipated to reduce the measurement uncertainty for both uranium and nitric acid. The online …
Date: October 29, 2008
Creator: Lascola, R.
Object Type: Report
System: The UNT Digital Library
A Compact Linac for Proton Therapy Based on a Dielectric Wall Accelerator (open access)

A Compact Linac for Proton Therapy Based on a Dielectric Wall Accelerator

A novel compact CT-guided intensity modulated proton radiotherapy (IMPT) system is described. The system is being designed to deliver fast IMPT so that larger target volumes and motion management can be accomplished. The system will be ideal for large and complex target volumes in young patients. The basis of the design is the dielectric wall accelerator (DWA) system being developed at the Lawrence Livermore National Laboratory (LLNL). The DWA uses fast switched high voltage transmission lines to generate pulsed electric fields on the inside of a high gradient insulating (HGI) acceleration tube. High electric field gradients are achieved by the use of alternating insulators and conductors and short pulse times. The system will produce individual pulses that can be varied in intensity, energy and spot width. The IMPT planning system will optimize delivery characteristics. The system will be capable of being sited in a conventional linac vault and provide intensity modulated rotational therapy. Feasibility tests of an optimization system for selecting the position, energy, intensity and spot size for a collection of spots comprising the treatment are underway. A prototype is being designed and concept designs of the envelope and environmental needs of the unit are beginning. The status of …
Date: October 29, 2007
Creator: Caporaso, G. J.; Mackie, T. R.; Sampayan, S.; Chen, Y.; Wang, L.; Blackfield, D. et al.
Object Type: Article
System: The UNT Digital Library
CONSTRAINT EFFECT IN FRACTURE WHAT IS IT (open access)

CONSTRAINT EFFECT IN FRACTURE WHAT IS IT

The meaning of the phrase 'constraint effect in fracture' has changed in the past two decades from 'contained plasticity' to a broader description of 'dependence of fracture toughness value on geometry of test specimen or structure'. This paper will first elucidate the fundamental mechanics reasons for the apparent 'constraint effects in fracture', followed by outlining a straightforward approach to overcoming this problem in both brittle (elastic) and ductile (elastic-plastic) fracture. It is concluded by discussing the major difference in constraint effect on fracture event in elastic and elastic-plastic materials.
Date: October 29, 2008
Creator: Lam, P & Prof. Yuh J. Chao, P
Object Type: Article
System: The UNT Digital Library
A High-Speed Detector System for X-ray Fluorescence Microprobes. (open access)

A High-Speed Detector System for X-ray Fluorescence Microprobes.

We have developed a high-speed system for collecting x-ray fluorescence microprobe data, based on ASICs developed at BNL and high-speed processors developed by CSIRO. The system can collect fluorescence data in a continuous raster scan mode, and present elemental images in real time using Ryan's Dynamic Analysis algorithm. We will present results from a 32-element prototype array illustrating the concept. The final instrument will have 384 elements arranged in a square array around a central hole.
Date: October 29, 2006
Creator: Siddons, P. D.; Dragone, A.; De Geronimo, G.; Kuczewski, A. & Kuczewski, J.
Object Type: Article
System: The UNT Digital Library
Remaining Sites Verification Package for the 100-F-26:9, 1607-F2 Sanitary Sewer Pipelines, Waste Site Reclassification Form 2008-029 (open access)

Remaining Sites Verification Package for the 100-F-26:9, 1607-F2 Sanitary Sewer Pipelines, Waste Site Reclassification Form 2008-029

The 100-F-26:9 underground pipeline subsite consists of the sanitary sewers servicing the 105-F, 108-F, 184-F, 185-F, and 190-F buildings, and the 1700-F administration and service buildings (1704-F, 1707-F, 1707-FA, 1713-F, 1717-F, 1719-F, and 1722-F). In accordance with this evaluation, the confirmatory and verification sampling results support a reclassification of this site to Interim Closed Out. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date: October 29, 2008
Creator: Capron, J. M.
Object Type: Report
System: The UNT Digital Library
X-Ray Active Matrix Pixel Sensors Basedon J-FET Technology Developed for the Linac Coherent Light Source. (open access)

X-Ray Active Matrix Pixel Sensors Basedon J-FET Technology Developed for the Linac Coherent Light Source.

An X-ray Active Matrix Pixel Sensor (XAMPS) is being developed for recording data for the X-ray Pump Probe experiment at the Linac Coherent Light Source (LCLS). Special attention has to be paid to some technological challenges that this design presents. New processes were developed and refined to address problems encountered during previous productions of XAMPS. The development of these critical steps and corresponding tests results are reported here.
Date: October 29, 2007
Creator: Carini, G. A.; Chen, W.; Li, Z.; Rehak, P. & Siddons, D. P.
Object Type: Article
System: The UNT Digital Library
In-situ X-ray photoelectron spectroscopy studies of water on metals and oxides at ambient conditions (open access)

In-situ X-ray photoelectron spectroscopy studies of water on metals and oxides at ambient conditions

X-ray photoelectron spectroscopy (XPS) is a powerful tool for surface and interface analysis, providing the elemental composition of surfaces and the local chemical environment of adsorbed species. Conventional XPS experiments have been limited to ultrahigh vacuum (UHV) conditions due to a short mean free path of electrons in a gas phase. The recent advances in instrumentation coupled with third-generation synchrotron radiation sources enables in-situ XPS measurements at pressures above 5 Torr. In this review, we describe the basic design of the ambient pressure XPS setup that combines differential pumping with an electrostatic focusing. We present examples of the application of in-situ XPS to studies of water adsorption on the surface of metals and oxides including Cu(110), Cu(111), TiO2(110) under environmental conditions of water vapor pressure. On all these surfaces we observe a general trend where hydroxyl groups form first, followed by molecular water adsorption. The importance of surface OH groups and their hydrogen bonding to water molecules in water adsorption on surfaces is discussed in detail.
Date: October 29, 2007
Creator: Salmeron, Miquel; Yamamoto, S.; Bluhm, H.; Andersson, K.; Ketteler, G.; Ogasawara, H. et al.
Object Type: Article
System: The UNT Digital Library
NREL's FY09 CSP Resource Assessment Plans: Solar Resource Assessment Workshop (open access)

NREL's FY09 CSP Resource Assessment Plans: Solar Resource Assessment Workshop

Solar Resource Assessment Workshop, Denver CO, Oct 29, 2008 presentation: NREL's FY09 CSP Resource Assessment Plans
Date: October 29, 2008
Creator: Renne, D.
Object Type: Article
System: The UNT Digital Library
Uncertainty for Satellite and Station Solar Data in the Updated NSRDB (open access)

Uncertainty for Satellite and Station Solar Data in the Updated NSRDB

Solar Resource Assessment Workshop, Denver CO, Oct 29, 2008 presentation: Uncertainty for Satellite and Station Solar Data in the Updated NSRDB,
Date: October 29, 2008
Creator: Myers, D. R.
Object Type: Article
System: The UNT Digital Library
Neutron Capture gamma ENDF libraries for modeling and identification of neutron sources (open access)

Neutron Capture gamma ENDF libraries for modeling and identification of neutron sources

There are a number of inaccuracies and data omissions with respect to gammas from neutron capture in the ENDF libraries used as field reference information and by modeling codes used in JTOT. As the use of Active Neutron interrogation methods is expanded, these shortfalls become more acute. A new, more accurate and complete evaluated experimental database of gamma rays (over 35,000 lines for 262 isotopes up to U so far) from thermal neutron capture has recently become available from the IAEA. To my knowledge, none of this new data has been installed in ENDF libraries and disseminated. I propose to upgrade libraries of {sup 184,186}W, {sup 56}Fe, {sup 204,206,207}Pb, {sup 104}Pd, and {sup 19}F the 1st year. This will involve collaboration with Richard Firestone at LBL in evaluating the data and installing it in the libraries. I will test them with the transport code MCNP5.
Date: October 29, 2007
Creator: Sleaford, B
Object Type: Report
System: The UNT Digital Library
REMOVAL OF TECHNETIUM 99 FROM THE EFFLUENT TREATMENT FACILITY (ETF) BASIN 44 USING PUROLITE A-530E & REILLEX HPQ & SYBRON IONAC SR-7 ION EXCHANGE RESINS (open access)

REMOVAL OF TECHNETIUM 99 FROM THE EFFLUENT TREATMENT FACILITY (ETF) BASIN 44 USING PUROLITE A-530E & REILLEX HPQ & SYBRON IONAC SR-7 ION EXCHANGE RESINS

This report documents the laboratory testing and analyses as directed under the test plan, RPP-20407. The overall goal of this task was to evaluate and compare candidate anion exchange resins for their capacity to remove Technetium-99 from Basin 44 Reverse Osmosis reject stream. The candidate resins evaluated were Purolite A-530E, Reillex HPQ, and Sybron IONAC SR-7.
Date: October 29, 2004
Creator: JB, DUNCAN
Object Type: Report
System: The UNT Digital Library
LIQUID EFFLUENT RETENTION FACILITY (LERF) BASIN 42 STUDIES (open access)

LIQUID EFFLUENT RETENTION FACILITY (LERF) BASIN 42 STUDIES

This report documents laboratory results obtained under test plan RPP-21533 for samples submitted by the Effluent Treatment Facility (ETF) from the Liquid Effluent Retention Facility (LERF) Basin 42 (Reference 1). The LERF Basin 42 contains process condensate (PC) from the 242-A Evaporator and landfill leachate. The ETF processes one PC campaign approximately every 12 to 18 months. A typical PC campaign volume can range from 1.5 to 2.5 million gallons. During the September 2003 ETF Basin 42 processing campaign, a recurring problem with 'gelatinous buildup' on the outlet filters from 60A-TK-I (surge tank) was observed (Figure 1). This buildup appeared on the filters after the contents of the surge tank were adjusted to a pH of between 5 and 6 using sulfuric acid. Biological activity in the PC feed was suspected to be the cause of the gelatinous material. Due to this buildup, the filters (10 {micro}m CUNO) required daily change out to maintain process throughput.
Date: October 29, 2004
Creator: JB, DUNCAN
Object Type: Report
System: The UNT Digital Library
Effect of Random Clustering on Surface Damage Density Estimates (open access)

Effect of Random Clustering on Surface Damage Density Estimates

Identification and spatial registration of laser-induced damage relative to incident fluence profiles is often required to characterize the damage properties of laser optics near damage threshold. Of particular interest in inertial confinement laser systems are large aperture beam damage tests (>1cm{sup 2}) where the number of initiated damage sites for {phi}>14J/cm{sup 2} can approach 10{sup 5}-10{sup 6}, requiring automatic microscopy counting to locate and register individual damage sites. However, as was shown for the case of bacteria counting in biology decades ago, random overlapping or 'clumping' prevents accurate counting of Poisson-distributed objects at high densities, and must be accounted for if the underlying statistics are to be understood. In this work we analyze the effect of random clumping on damage initiation density estimates at fluences above damage threshold. The parameter {psi} = a{rho} = {rho}/{rho}{sub 0}, where a = 1/{rho}{sub 0} is the mean damage site area and {rho} is the mean number density, is used to characterize the onset of clumping, and approximations based on a simple model are used to derive an expression for clumped damage density vs. fluence and damage site size. The influence of the uncorrected {rho} vs. {phi} curve on damage initiation probability predictions is …
Date: October 29, 2007
Creator: Matthews, M J & Feit, M D
Object Type: Article
System: The UNT Digital Library
Inelastic final-state interaction (open access)

Inelastic final-state interaction

The final-state interaction in multichannel decay processes is systematically studied with application to B decay in mind. Since the final-state interaction is intrinsically interwoven with the decay interaction in this case, no simple phase theorem like"Watson's theorem" holds for experimentally observed final states. We first examine in detail the two-channel problem as a toy-model to clarify the issues and to remedy common mistakes made in earlier literature. Realistic multichannel problems are too challenging for quantitative analysis. To cope with mathematical complexity, we introduce a method of approximation that is applicable to the case where one prominent inelastic channel dominates over all others. We illustrate this approximation method in the amplitude of the decay B to pi K fed by the intermediate states of a charmed meson pair. Even with our approximation we need more accurate information of strong interactions than we have now. Nonetheless we are able to obtain some insight in the issue and draw useful conclusions on general features on the strong phases.
Date: October 29, 2007
Creator: Suzuki, Mahiko & Suzuki, Mahiko
Object Type: Article
System: The UNT Digital Library
Downstream Intensification Effects Associated with CO2 Laser Mitigation of Fused Silica (open access)

Downstream Intensification Effects Associated with CO2 Laser Mitigation of Fused Silica

Mitigation of 351nm laser-induced damage sites on fused silica exit surfaces by selective CO{sub 2} treatment has been shown to effectively arrest the exponential growth responsible for limiting the lifetime of optics in high-fluence laser systems. However, the perturbation to the optical surface profile following the mitigation process introduces phase contrast to the beam, causing some amount of downstream intensification with the potential to damage downstream optics. Control of the laser treatment process and measurement of the associated phase modulation is essential to preventing downstream 'fratricide' in damage-mitigated optical systems. In this work we present measurements of the surface morphology, intensification patterns and damage associated with various CO{sub 2} mitigation treatments on fused silica surfaces. Specifically, two components of intensification pattern, one on-axis and another off-axis can lead to damage of downstream optics and are related to rims around the ablation pit left from the mitigation process. It is shown that control of the rim structure around the edge of typical mitigation sites is crucial in preventing damage to downstream optics.
Date: October 29, 2007
Creator: Matthews, M. J.; Bass, I. L.; Guss, G. M.; Widmayer, C. C. & Ravizza, F. L.
Object Type: Article
System: The UNT Digital Library
Growth of laser damage in fused silica: diameter to depth ratio (open access)

Growth of laser damage in fused silica: diameter to depth ratio

Growth of laser initiated damage plays a major role in determining optics lifetime in high power laser systems. Previous measurements have established that the lateral diameter grows exponentially. Knowledge of the growth of the site in the propagation direction is also important, especially so when considering techniques designed to mitigate damage growth, where it is required to reach all the subsurface damage. In this work, we present data on both the diameter and the depth of a growing exit surface damage sites in fused silica. Measured growth rates with both 351 nm illumination and with combined 351 nm and 1054 nm illumination are discussed.
Date: October 29, 2007
Creator: Norton, M. A.; Adams, J. J.; Carr, C. W.; Donohue, E. E.; Feit, M. D.; Hackel, R. P. et al.
Object Type: Article
System: The UNT Digital Library
Design for a High Energy Density Kelvin-Helmholtz Experiment (open access)

Design for a High Energy Density Kelvin-Helmholtz Experiment

While many high energy density physics (HEDP) Rayleigh-Taylor and Richtmyer-Meshkov instability experiments have been fielded as part of basic HEDP and astrophysics studies, not one HEDP Kelvin-Helmholtz (KH) experiment has been successfully performed. Herein, a design for a novel HEDP x-ray driven KH experiment is presented along with supporting radiation-hydrodynamic simulation and theory.
Date: October 29, 2007
Creator: Hurricane, O A
Object Type: Article
System: The UNT Digital Library
Wavelet Denoising of Mobile Radiation Data (open access)

Wavelet Denoising of Mobile Radiation Data

The investigation of wavelet analysis techniques as a means of filtering the gross-count signal obtained from radiation detectors has shown promise. These signals are contaminated with high frequency statistical noise and significantly varying background radiation levels. Wavelet transforms allow a signal to be split into its constituent frequency components without losing relative timing information. Initial simulations and an injection study have been performed. Additionally, acquisition and analysis software has been written which allowed the technique to be evaluated in real-time under more realistic operating conditions. The technique performed well when compared to more traditional triggering techniques with its performance primarily limited by false alarms due to prominent features in the signal. An initial investigation into the potential rejection and classification of these false alarms has also shown promise.
Date: October 29, 2007
Creator: Campbell, D & Lanier, R
Object Type: Report
System: The UNT Digital Library
SRNL PARTICIPATION IN THE MULTI-SCALE ENSEMBLE EXERCISES (open access)

SRNL PARTICIPATION IN THE MULTI-SCALE ENSEMBLE EXERCISES

Consequence assessment during emergency response often requires atmospheric transport and dispersion modeling to guide decision making. A statistical analysis of the ensemble of results from several models is a useful way of estimating the uncertainty for a given forecast. ENSEMBLE is a European Union program that utilizes an internet-based system to ingest transport results from numerous modeling agencies. A recent set of exercises required output on three distinct spatial and temporal scales. The Savannah River National Laboratory (SRNL) uses a regional prognostic model nested within a larger-scale synoptic model to generate the meteorological conditions which are in turn used in a Lagrangian particle dispersion model. A discussion of SRNL participation in these exercises is given, with particular emphasis on requirements for provision of results in a timely manner with regard to the various spatial scales.
Date: October 29, 2007
Creator: Buckley, R
Object Type: Article
System: The UNT Digital Library
Evaluation of Neutron Cross Sections for a Complete Set of Nd Isotopes. (open access)

Evaluation of Neutron Cross Sections for a Complete Set of Nd Isotopes.

Neutron cross sections for a complete set of Nd isotopes, {sup 142,143,144,145,146,147,148,150}Nd, were evaluated in the incident energy range from 10{sup -5} eV to 20 MeV. In the low energy region, including thermal and resolved resonances, our evaluations are based on the latest data published in the Atlas of Neutron Resonances. In the unresolved resonance region we performed additional evaluation by using the averages of the resolved resonances and adjusting them to the experimental data. In the fast neutron region, we used the nuclear reaction model code EMPIRE-2.19 validated against the experimental data. The results are compared to the existing nuclear data libraries, including ENDF/B-VI.8, JENDL-3.3 and JEFF-3.1, and to the available experimental data. The new evaluations are suitable for neutron transport calculations and they were adopted by the new evaluated nuclear data file of the United States, ENDF/B-VII.0, released in December 2006.
Date: October 29, 2007
Creator: Kim, H.; Herman, M.; Mughabghab, S. F.; Oblozinsky, P.; Rochman, D. & Lee, Y. O.
Object Type: Report
System: The UNT Digital Library
Recent Work in Multiphase Flow at NETL (open access)

Recent Work in Multiphase Flow at NETL

No abstract - only slideshow attached
Date: October 29, 2007
Creator: Syamlal, Madhava
Object Type: Article
System: The UNT Digital Library
Scientific Data Management Integrated Software Infrastructure Center (open access)

Scientific Data Management Integrated Software Infrastructure Center

This work provides software that enables scientific applications to more efficiently access available storage resources at different levels of interfaces. We developed scalable techniques and optimizations for PVFS parallel file systems, MPI I/O, and parallel netCDF I/O library. These implementations were evaluated using production application I/O kernels as well as popular I/O benchmarks and demonstrated promising results. The software developed under this work has been made available to the public via MCS, ANL web sites.
Date: October 29, 2008
Creator: Choudhary, A. & Liao, W.K.
Object Type: Report
System: The UNT Digital Library
LIGHT INDUCED TELLURIUM ENRICHMENT ON CDZNTE CRYSTALSURFACES DETECTED BY RAMAN SPECTROSCOPY (open access)

LIGHT INDUCED TELLURIUM ENRICHMENT ON CDZNTE CRYSTALSURFACES DETECTED BY RAMAN SPECTROSCOPY

Synthetic CdZnTe or 'CZT' crystals can be grown under controlled conditions to produce high quality crystals to be used as room temperature radiation detectors. Even the best crystal growth methods result in defects, such as tellurium secondary phases, that affect the crystal's performance. In this study, CZT crystals were analyzed by micro Raman spectroscopy. The growth of Te rich areas on the surface was induced by low powered lasers. The growth was observed versus time with low power Raman scattering and was observed immediately under higher power conditions. The detector response was also measured after induced Te enrichment.
Date: October 29, 2007
Creator: Hawkins, S; Eliel Villa-Aleman, E; Martine Duff, M & Douglas02 Hunter, D
Object Type: Article
System: The UNT Digital Library