Parameterization of the Extinction Coefficient in Ice and Mixed-Phase Arctic Clouds during the ISDAC Field Campaign (open access)

Parameterization of the Extinction Coefficient in Ice and Mixed-Phase Arctic Clouds during the ISDAC Field Campaign

This report documents the history of attempts to directly measure cloud extinction, the current measurement device known as the Cloud Extinction Probe (CEP), specific problems with direct measurement of extinction coefficient, and the attempts made here to address these problems. Extinction coefficient is one of the fundamental microphysical parameters characterizing bulk properties of clouds. Knowledge of extinction coefficient is of crucial importance for radiative transfer calculations in weather prediction and climate models given that Earth's radiation budget (ERB) is modulated much by clouds. In order for a large-scale model to properly account for ERB and perturbations to it, it must ultimately be able to simulate cloud extinction coefficient well. In turn this requires adequate and simultaneous simulation of profiles of cloud water content and particle habit and size. Similarly, remote inference of cloud properties requires assumptions to be made about cloud phase and associated single-scattering properties, of which extinction coefficient is crucial. Hence, extinction coefficient plays an important role in both application and validation of methods for remote inference of cloud properties from data obtained from both satellite and surface sensors (e.g., Barker et al. 2008). While estimation of extinction coefficient within large-scale models is relatively straightforward for pure water …
Date: March 6, 2012
Creator: Korolev, A; Shashkov, A & Barker, H
Object Type: Report
System: The UNT Digital Library
Variable Beam Attenuators for Synchrotron Radiation (open access)

Variable Beam Attenuators for Synchrotron Radiation

None
Date: March 6, 2013
Creator: Hasi, Jasmine; Kenney, C. J.; Via, Cinzia Da; Parker, Sherwood I.; Thompson, A. C. & Westbrook, E. M.
Object Type: Article
System: The UNT Digital Library
Biomass Gas Cleanup Using a Therminator (open access)

Biomass Gas Cleanup Using a Therminator

The objective of the project is to develop and demonstrate a novel fluidized-bed process module called a “Therminator” to simultaneously destroy and/or remove tar, NH3 and H2S from raw syngas produced by a fluidized-bed biomass gasifier. The raw syngas contains as much as 10 g/m3 of tar, 4,000 ppmv of NH3 and 100 ppmv of H2S. The goal of the Therminator module would be to use promising regenerable catalysts developed for removing tar, ammonia, and H2S down to low levels (around 10 ppm). Tars are cracked to a non-condensable gas and coke that would deposit on the acid catalyst. We will deposit coke, much like a fluid catalytic cracker (FCC) in a petroleum refinery. The deposited coke fouls the catalyst, much like FCC, but the coke would be burned off in the regenerator and the regenerated catalyst would be returned to the cracker. The rapid circulation between the cracker and regenerator would ensure the availability of the required amount of regenerated catalyst to accomplish our goal. Also, by removing sulfur down to less than 10 ppmv, NH3 decomposition would also be possible in the cracker at 600-700°C. In the cracker, tar decomposes and lays down coke on the acid sites …
Date: March 6, 2012
Creator: Dayton, David C.; Kataria, Atish & Gupta, Rabhubir
Object Type: Report
System: The UNT Digital Library
Grand Challenges of Advanced Computing for Energy Innovation Report from the Workshop Held July 31-August 2, 2012 (open access)

Grand Challenges of Advanced Computing for Energy Innovation Report from the Workshop Held July 31-August 2, 2012

On July 31-August 2 of 2012, the U.S. Department of Energy (DOE) held a workshop entitled Grand Challenges of Advanced Computing for Energy Innovation. This workshop built on three earlier workshops that clearly identified the potential for the Department and its national laboratories to enable energy innovation. The specific goal of the workshop was to identify the key challenges that the nation must overcome to apply the full benefit of taxpayer-funded advanced computing technologies to U.S. energy innovation in the ways that the country produces, moves, stores, and uses energy. Perhaps more importantly, the workshop also developed a set of recommendations to help the Department overcome those challenges. These recommendations provide an action plan for what the Department can do in the coming years to improve the nation’s energy future.
Date: March 6, 2013
Creator: Larzelere, Alex R.; Ashby, Steven F.; Christensen, Dana C.; Crawford, Dona L.; Khaleel, Mohammad A.; John, Grosh et al.
Object Type: Report
System: The UNT Digital Library
A High Resolution Monolithic Crystal, DOI, MR Compatible, PET Detector (open access)

A High Resolution Monolithic Crystal, DOI, MR Compatible, PET Detector

The principle objective of this proposal is to develop a positron emission tomography (PET) detector with depth-of-interaction (DOI) positioning capability that will achieve state of the art spatial resolution and sensitivity performance for small animal PET imaging. When arranged in a ring or box detector geometry, the proposed detector module will support <1 mm3 image resolution and >15% absolute detection efficiency. The detector will also be compatible with operation in a MR scanner to support simultaneous multi-modality imaging. The detector design will utilize a thick, monolithic crystal scintillator readout by a two-dimensional array of silicon photomultiplier (SiPM) devices using a novel sensor on the entrance surface (SES) design. Our hypothesis is that our single-ended readout SES design will provide an effective DOI positioning performance equivalent to more expensive dual-ended readout techniques and at a significantly lower cost. Our monolithic crystal design will also lead to a significantly lower cost system. It is our goal to design a detector with state of the art performance but at a price point that is affordable so the technology can be disseminated to many laboratories. A second hypothesis is that using SiPM arrays, the detector will be able to operate in a MR scanner …
Date: March 6, 2012
Creator: Miyaoka, Robert S
Object Type: Report
System: The UNT Digital Library
Summary Report of the Consultants Meeting on Further Development of EXFOR (open access)

Summary Report of the Consultants Meeting on Further Development of EXFOR

N/A
Date: March 6, 2012
Creator: D., Brown
Object Type: Report
System: The UNT Digital Library
Management Principles for Nonproliferation Organizations (open access)

Management Principles for Nonproliferation Organizations

This paper identifies business models and six management principles that can be applied by a nonproliferation organization to maximize the value and effectiveness of its products. The organizations responsible for reducing the nuclear proliferation threat have experienced a substantial growth in responsibility and visibility since the September 11 attacks. Since then, the international community has witnessed revelations of clandestine nuclear facilities, nuclear black markets, periodic nuclear tests, and a resurgence of interest by countries worldwide in developing nuclear capabilities. The security environment will likely continue to evolve in unexpected ways since most of the proliferation threats with which the world will be forced to contend remain unforeseen. To better prepare for and respond to this evolving security environment, many nonproliferation organizations are interested in finding new or better ways to increase the effectiveness and efficiency of their operations. Of course, all organizations, whether they are market driven or non-profit, must operate effectively and efficiently if they are to succeed. Indeed, as this study demonstrates, many of the management principles that this study recommends can help all organizations succeed. However, this study pays particular attention to nonproliferation organizations because of the mission they are responsible for fulfilling. Nonproliferation organizations, including nonproliferation …
Date: March 6, 2012
Creator: Frazar, Sarah L. & Hund, Gretchen
Object Type: Report
System: The UNT Digital Library
Nanoscale Spin Reversal by Nonlocal Angular Momentum Transfer following Ultrafast Laser Excitation in Ferrimagnetic GdFeCo (open access)

Nanoscale Spin Reversal by Nonlocal Angular Momentum Transfer following Ultrafast Laser Excitation in Ferrimagnetic GdFeCo

None
Date: March 6, 2013
Creator: Graves, C.; Reid, A. H.; Wang, T.; Wu, B.; de Jong, S.; Vahaplar, K. et al.
Object Type: Article
System: The UNT Digital Library
Mesoscale Modeling of LX-17 Under Isentropic Compression (open access)

Mesoscale Modeling of LX-17 Under Isentropic Compression

Mesoscale simulations of LX-17 incorporating different equilibrium mixture models were used to investigate the unreacted equation-of-state (UEOS) of TATB. Candidate TATB UEOS were calculated using the equilibrium mixture models and benchmarked with mesoscale simulations of isentropic compression experiments (ICE). X-ray computed tomography (XRCT) data provided the basis for initializing the simulations with realistic microstructural details. Three equilibrium mixture models were used in this study. The single constituent with conservation equations (SCCE) model was based on a mass-fraction weighted specific volume and the conservation of mass, momentum, and energy. The single constituent equation-of-state (SCEOS) model was based on a mass-fraction weighted specific volume and the equation-of-state of the constituents. The kinetic energy averaging (KEA) model was based on a mass-fraction weighted particle velocity mixture rule and the conservation equations. The SCEOS model yielded the stiffest TATB EOS (0.121{micro} + 0.4958{micro}{sup 2} + 2.0473{micro}{sup 3}) and, when incorporated in mesoscale simulations of the ICE, demonstrated the best agreement with VISAR velocity data for both specimen thicknesses. The SCCE model yielded a relatively more compliant EOS (0.1999{micro}-0.6967{micro}{sup 2} + 4.9546{micro}{sup 3}) and the KEA model yielded the most compliant EOS (0.1999{micro}-0.6967{micro}{sup 2}+4.9546{micro}{sup 3}) of all the equilibrium mixture models. Mesoscale simulations with the …
Date: March 6, 2010
Creator: Springer, H K; Willey, T M; Friedman, G; Fried, L E; Vandersall, K S & Baer, M R
Object Type: Article
System: The UNT Digital Library
LITERATURE REVIEW OF PUO2 CALCINATION TIME AND TEMPERATURE DATA FOR SPECIFIC SURFACE AREA (open access)

LITERATURE REVIEW OF PUO2 CALCINATION TIME AND TEMPERATURE DATA FOR SPECIFIC SURFACE AREA

The literature has been reviewed in December 2011 for calcination data of plutonium oxide (PuO{sub 2}) from plutonium oxalate Pu(C{sub 2}O{sub 4}){sub 2} precipitation with respect to the PuO{sub 2} specific surface area (SSA). A summary of the literature is presented for what are believed to be the dominant factors influencing SSA, the calcination temperature and time. The PuO{sub 2} from Pu(C{sub 2}O{sub 4}){sub 2} calcination data from this review has been regressed to better understand the influence of calcination temperature and time on SSA. Based on this literature review data set, calcination temperature has a bigger impact on SSA versus time. However, there is still some variance in this data set that may be reflecting differences in the plutonium oxalate preparation or different calcination techniques. It is evident from this review that additional calcination temperature and time data for PuO{sub 2} from Pu(C{sub 2}O{sub 4}){sub 2} needs to be collected and evaluated to better define the relationship. The existing data set has a lot of calcination times that are about 2 hours and therefore may be underestimating the impact of heating time on SSA. SRNL recommends that more calcination temperature and time data for PuO{sub 2} from Pu(C{sub 2}O{sub …
Date: March 6, 2012
Creator: Daniel, G.
Object Type: Report
System: The UNT Digital Library
Rhodium mediated bond activation: from synthesis to catalysis (open access)

Rhodium mediated bond activation: from synthesis to catalysis

Recently, our lab has developed monoanionic tridentate ligand, To{sup R}, showing the corresponding coordination chemistry and catalyst reactivity of magnesium, zirconium, zinc and iridium complexes. This thesis details synthetic chemistry, structural study and catalytic reactivity of the To{sup R}-supported rhodium compounds. Tl[To{sup R}] has been proved to be a superior ligand transfer agent for synthesizing rhodium complexes. The salt metathesis route of Tl[To{sup M}] with [Rh({mu}-Cl)(CO)]{sub 2} and [Rh({mu}- Cl)(COE)]{sub 2} gives To{sup M}Rh(CO){sub 2} (2.2) and To{sup M}RhH({eta}{sup 3}-C{sub 8}H{sub 13}) (3.1) respectively while Tl[To{sup P}] with [Rh({mu}-Cl)(CO)]{sub 2} affords To{sup P}Rh(CO){sub 2} (2.3). 2.2 reacts with both strong and weak electrophiles, resulting in the oxazoline N-attacked and the metal center-attacked compounds correspondingly. Using one of the metal center-attacked electrophiles, 2.3 was demonstrated to give high diastereoselectivity. Parallel to COE allylic C-H activation complex 3.1, the propene and allylbenzene allylic C-H activation products have also been synthesized. The subsequent functionalization attempts have been examined by treating with Brønsted acids, Lewis acids, electrophiles, nucleophiles, 1,3-dipolar reagents and reagents containing multiple bonds able to be inserted. Various related complexes have been obtained under these conditions, in which one of the azide insertion compounds reductively eliminates to give an allylic functionalization product …
Date: March 6, 2012
Creator: Ho, Hung-An
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Theoretical Research at the High Energy Frontier: Cosmology, Neutrinos, and Beyond (open access)

Theoretical Research at the High Energy Frontier: Cosmology, Neutrinos, and Beyond

The DOE theory group grew from 2009-2012 from a single investigator, Lawrence Krauss, the PI on the grant, to include 3 faculty (with the addition of Maulik Parikh and Tanmay Vachaspati), and a postdoc covered by the grant, as well as partial support for a graduate student. The group has explored issues ranging from gravity and quantum field theory to topological defects, energy conditions in general relativity, primordial magnetic fields, neutrino astrophysics, quantum phases, gravitational waves from the early universe, dark matter detection schemes, signatures for dark matter at the LHC, and indirect astrophysical signatures for dark matter. In addition, we have run active international workshops each year, as well as a regular visitor program. As well, the PI's outreach activities, including popular books and articles, and columns for newspapers and magazines, as well as television and radio appearances have helped raise the profile of high energy physics internationally. The postdocs supported by the grant, James Dent and Roman Buniy have moved on successfully to a faculty positions in Louisiana and California.
Date: March 6, 2013
Creator: Krauss, Lawrence M; Vachaspati, Tanmay & Parikh, Maulik
Object Type: Report
System: The UNT Digital Library
SE-CSE 2013: The 2013 International Workshop on Software Engineering for Computational Science and Engineering (open access)

SE-CSE 2013: The 2013 International Workshop on Software Engineering for Computational Science and Engineering

None
Date: March 6, 2013
Creator: Carver, J C; Epperly, T W; Hochstein, L; Maxville, V; Pfahl, D & Silliito, J
Object Type: Article
System: The UNT Digital Library
SRNL PHASE 1 ASSESSMENT OF THE WTP WASTE QUALIFICATION PROGRAM (open access)

SRNL PHASE 1 ASSESSMENT OF THE WTP WASTE QUALIFICATION PROGRAM

The Hanford Tank Waste Treatment and Immobilization Plant (WTP) Project is currently transitioning its emphasis from an engineering design and construction phase toward facility completion, start-up and commissioning. With this transition, the WTP Project has initiated more detailed assessments of the requirements that must be met during the actual processing of the Hanford Site tank waste. One particular area of interest is the waste qualification program. In general, the waste qualification program involves testing and analysis to demonstrate compliance with waste acceptance criteria, determine waste processability, and demonstrate laboratory-scale unit operations to support WTP operations. The testing and analysis are driven by data quality objectives (DQO) requirements necessary for meeting waste acceptance criteria for transfer of high-level wastes from the tank farms to the WTP, and for ensuring waste processability including proper glass formulations during processing within the WTP complex. Given the successful implementation of similar waste qualification efforts at the Savannah River Site (SRS) which were based on critical technical support and guidance from the Savannah River National Laboratory (SRNL), WTP requested subject matter experts (SMEs) from SRNL to support a technology exchange with respect to waste qualification programs in which a critical review of the WTP program could …
Date: March 6, 2012
Creator: Peeler, D.; Hansen, E.; Herman, C.; Marra, S. & Wilmarth, B.
Object Type: Report
System: The UNT Digital Library
Data Summary Report for Hanford Site Coal Ash Characterization (open access)

Data Summary Report for Hanford Site Coal Ash Characterization

The purpose of this report is to present data and findings from sampling and analysis of five distinct areas of coal ash within the Hanford Site River Corridor
Date: March 6, 2012
Creator: Sulloway, H. M.
Object Type: Report
System: The UNT Digital Library
A Filament of Dark Matter Between Two Clusters of Galaxies (open access)

A Filament of Dark Matter Between Two Clusters of Galaxies

None
Date: March 6, 2013
Creator: Dietrich, Jorg P.; Werner, Norbert; Clowe, Douglas; Finoguenov, Alexis; Kitching, Tom; Miller, Lance et al.
Object Type: Article
System: The UNT Digital Library
Calculation of Kinetics Parameters for the NBSR (open access)

Calculation of Kinetics Parameters for the NBSR

The delayed neutron fraction and prompt neutron lifetime have been calculated at different times in the fuel cycle for the NBSR when fueled with both high-enriched uranium (HEU) and low-enriched uranium (LEU) fuel. The best-estimate values for both the delayed neutron fraction and the prompt neutron lifetime are the result of calculations using MCNP5-1.60 with the most recent ENDFB-VII evaluations. The best-estimate values for the total delayed neutron fraction from fission products are 0.00665 and 0.00661 for the HEU fueled core at startup and end-of-cycle, respectively. For the LEU fuel the best estimate values are 0.00650 and 0.00648 at startup and end-of-cycle, respectively. The present recommendations for the delayed neutron fractions from fission products are smaller than the value reported previously of 0.00726 for the HEU fuel. The best-estimate values for the contribution from photoneutrons will remain as 0.000316, independent of the fuel or time in the cycle.The values of the prompt neutron lifetime as calculated with MCNP5-1.60 are compared to values calculated with two other independent methods and the results are in reasonable agreement with each other. The recommended, conservative values of the neutron lifetime for the HEU fuel are 650 {micro}s and 750 {micro}s for the startup and …
Date: March 6, 2012
Creator: L., Hanson A. & D., Diamond
Object Type: Report
System: The UNT Digital Library
FEL Oscillator for EUV Lithography (open access)

FEL Oscillator for EUV Lithography

Report on a study to develop radiation sources for extreme ultraviolet lithography (EUVL) by using a free-electron laser (FEL) with a short-period undulator and a relatively small beam energy.
Date: March 6, 2014
Creator: Stupakov, G. & Zolotorev, M. S.
Object Type: Article
System: The UNT Digital Library
Ka-Band ARM Zenith Radar (KAZR) Instrument Handbook (open access)

Ka-Band ARM Zenith Radar (KAZR) Instrument Handbook

The Ka-band ARM zenith radar (KAZR) is a zenith-pointing Doppler cloud radar operating at approximately 35 GHz. The KAZR is an evolutionary follow-on radar to ARM's widely successful millimeter-wavelength cloud radar (MMCR). The main purpose of the KAZR is to provide vertical profiles of clouds by measuring the first three Doppler moments: reflectivity, radial Doppler velocity, and spectra width. At the sites where the dual-polarization measurements are made, the Doppler moments for the cross-polarization channel are also available. In addition to the moments, velocity spectra are also continuously recorded for each range gate.
Date: March 6, 2012
Creator: Widener, K.; Bharadwaj, N. & Johnson, K.
Object Type: Report
System: The UNT Digital Library