In-situ spectro-microscopy on organic films: Mn-Phthalocyanine on Ag(100) (open access)

In-situ spectro-microscopy on organic films: Mn-Phthalocyanine on Ag(100)

Metal phthalocyanines are attracting significant attention, owing to their potential for applications in chemical sensors, solar cells and organic magnets. As the electronic properties of molecular films are determined by their crystallinity and molecular packing, the optimization of film quality is important for improving the performance of organic devices. Here, we present the results of in situ low-energy electron microscopy / photoemission electron microscopy (LEEM/PEEM) studies of incorporation-limited growth [1] of manganese-phthalocyanine (MnPc) on Ag(100) surfaces. MnPc thin films were grown on both, bulk Ag(100) surface and thin Ag(100)/Fe(100) films, where substrate spin-polarized electronic states can be modified through tuning the thickness of the Ag film [2]. We also discuss the electronic structure and magnetic ordering in MnPc thin films, investigated by angle- and spin-resolved photoemission spectroscopy.
Date: August 18, 2013
Creator: A., Al-Mahboob; Vescovo, E. & Sadowski, J.T.
Object Type: Article
System: The UNT Digital Library
Differential Thermal Analyses of CdMnZnTe Alloys (open access)

Differential Thermal Analyses of CdMnZnTe Alloys

N/A
Date: August 27, 2013
Creator: A., Bolotnikov
Object Type: Article
System: The UNT Digital Library
Side-surface passivation effect on the electrical properties of metal-CdZnTe-metal structures (open access)

Side-surface passivation effect on the electrical properties of metal-CdZnTe-metal structures

N/A
Date: August 25, 2013
Creator: A., Bolotnikov; Sklyarchuk, V.; Fochuk, P.; Zakharuk, Z.; Grill, R.; Kutny, V. Rybka, A. et al.
Object Type: Article
System: The UNT Digital Library
Transport Phenomena and Interfacial Kinetics in Planar Microfluidic Membraneless Fuel Cells (open access)

Transport Phenomena and Interfacial Kinetics in Planar Microfluidic Membraneless Fuel Cells

Our work is focused on membraneless laminar flow fuel cells, an unconventional fuel cell technology, intended to create a system that not only avoids most typical fuel cell drawbacks, but also achieves the highest power density yet recorded for a non-H{sub 2} fuel cell. We have employed rigorous electrochemistry to characterize the high-energy- density fuel BH4-, providing important mechanistic insight for anode catalyst choice and avoiding deleterious side reactions. Numerous fuel cell oxidants, used in place of O{sub 2}, are compared in a detailed, uniform manner, and a powerful new oxidant, cerium ammonium nitrate (CAN), is described. The high-voltage BH{sub 4}{sup -}/CAN fuel/oxidant combination is employed in a membraneless, room temperature, laminar-flow fuel cell, with herringbone micromixers which provide chaotic-convective flow which, in turn, enhances both the power output and efficiency of the device. We have also been involved in the design of a scaled-up version of the membraneless laminar flow fuel cell intended to provide a 10W output.
Date: August 1, 2013
Creator: Abruna, Hector Daniel
Object Type: Report
System: The UNT Digital Library
Hard Probes in Heavy Ion Collisions at the LHC: PDFs, Shadowing and $pA$ Collisions (open access)

Hard Probes in Heavy Ion Collisions at the LHC: PDFs, Shadowing and $pA$ Collisions

None
Date: August 7, 2013
Creator: Accardi, Alberto; Armesto, N.; Botje, M.; Brodsky, S. J.; Cole, B.; Eskola, K. J. et al.
Object Type: Article
System: The UNT Digital Library
Incorporating Cold Cap Behavior in a Joule-heated Waste Glass Melter Model (open access)

Incorporating Cold Cap Behavior in a Joule-heated Waste Glass Melter Model

In this paper, an overview of Joule-heated waste glass melters used in the vitrification of high level waste (HLW) is presented, with a focus on the cold cap region. This region, in which feed-to-glass conversion reactions occur, is critical in determining the melting properties of any given glass melter. An existing 1D computer model of the cold cap, implemented in MATLAB, is described in detail. This model is a standalone model that calculates cold cap properties based on boundary conditions at the top and bottom of the cold cap. Efforts to couple this cold cap model with a 3D STAR-CCM+ model of a Joule-heated melter are then described. The coupling is being implemented in ModelCenter, a software integration tool. The ultimate goal of this model is to guide the specification of melter parameters that optimize glass quality and production rate.
Date: August 1, 2013
Creator: Agarwal, Varija & Guillen, Donna Post
Object Type: Report
System: The UNT Digital Library
Multiphysics Integrated Coupling Environment (MICE) User Manual (open access)

Multiphysics Integrated Coupling Environment (MICE) User Manual

The complex, multi-part nature of waste glass melters used in nuclear waste vitrification poses significant modeling challenges. The focus of this project has been to couple a 1D MATLAB model of the cold cap region within a melter with a 3D STAR-CCM+ model of the melter itself. The Multiphysics Integrated Coupling Environment (MICE) has been developed to create a cohesive simulation of a waste glass melter that accurately represents the cold cap. The one-dimensional mathematical model of the cold cap uses material properties, axial heat, and mass fluxes to obtain a temperature profile for the cold cap, the region where feed-to-glass conversion occurs. The results from Matlab are used to update simulation data in the three-dimensional STAR-CCM+ model so that the cold cap is appropriately incorporated into the 3D simulation. The two processes are linked through ModelCenter integration software using time steps that are specified for each process. Data is to be exchanged circularly between the two models, as the inputs and outputs of each model depend on the other.
Date: August 1, 2013
Creator: Agarwal, Varija & Guillen, Donna Post
Object Type: Report
System: The UNT Digital Library
Materials Inventory Database for the Light Water Reactor Sustainability Program (open access)

Materials Inventory Database for the Light Water Reactor Sustainability Program

Scientific research involves the purchasing, processing, characterization, and fabrication of many sample materials. The history of such materials can become complicated over their lifetime – materials might be cut into pieces or moved to various storage locations, for example. A database with built-in functions to track these kinds of processes facilitates well-organized research. The Material Inventory Database Accounting System (MIDAS) is an easy-to-use tracking and reference system for such items. The Light Water Reactor Sustainability Program (LWRS), which seeks to advance the long-term reliability and productivity of existing nuclear reactors in the United States through multiple research pathways, proposed MIDAS as an efficient way to organize and track all items used in its research. The database software ensures traceability of all items used in research using built-in functions which can emulate actions on tracked items – fabrication, processing, splitting, and more – by performing operations on the data. MIDAS can recover and display the complete history of any item as a simple report. To ensure the database functions suitably for the organization of research, it was developed alongside a specific experiment to test accident tolerant nuclear fuel cladding under the LWRS Advanced Light Water Reactor Nuclear Fuels Pathway. MIDAS kept …
Date: August 1, 2013
Creator: Ahmed, Kazi & Bragg-Sitton, Shannon M.
Object Type: Report
System: The UNT Digital Library
X-ray diffraction diagnostic design for the National Ignition Facility (open access)

X-ray diffraction diagnostic design for the National Ignition Facility

None
Date: August 22, 2013
Creator: Ahmed, M F; Ayers, J; House, A; Lamb, Z; Swift, R & Swift, D
Object Type: Article
System: The UNT Digital Library
Overcoming Extreme-Scale Reproducibility Challenges Through a Unified, Targeted and Multilevel Toolset (open access)

Overcoming Extreme-Scale Reproducibility Challenges Through a Unified, Targeted and Multilevel Toolset

None
Date: August 13, 2013
Creator: Ahn, D H; Lee, G L; Gopalakrishnan, G; Rakamaric, Z; Schulz, M & Laguna, I
Object Type: Article
System: The UNT Digital Library
Rh-Based Mixed Alcohol Synthesis Catalysts: Characterization and Computational Report (open access)

Rh-Based Mixed Alcohol Synthesis Catalysts: Characterization and Computational Report

The U.S. Department of Energy is conducting a program focused on developing a process for the conversion of biomass to bio-based fuels and co-products. Biomass-derived syngas is converted thermochemically within a temperature range of 240 to 330°C and at elevated pressure (e.g., 1200 psig) over a catalyst. Ethanol is the desired reaction product, although other side compounds are produced, including C3 to C5 alcohols; higher (i.e., greater than C1) oxygenates such as methyl acetate, ethyl acetate, acetic acid and acetaldehyde; and higher hydrocarbon gases such as methane, ethane/ethene, propane/propene, etc. Saturated hydrocarbon gases (especially methane) are undesirable because they represent a diminished yield of carbon to the desired ethanol product and represent compounds that must be steam reformed at high energy cost to reproduce CO and H2. Ethanol produced by the thermochemical reaction of syngas could be separated and blended directly with gasoline to produce a liquid transportation fuel. Additionally, higher oxygenates and unsaturated hydrocarbon side products such as olefins also could be further processed to liquid fuels. The goal of the current project is the development of a Rh-based catalyst with high activity and selectivity to C2+ oxygenates. This report chronicles an effort to characterize numerous supports and catalysts …
Date: August 1, 2013
Creator: Albrecht, Karl O.; Glezakou, Vassiliki Alexandra; Rousseau, Roger J.; Engelhard, Mark H.; Varga, Tamas; Colby, Robert J. et al.
Object Type: Report
System: The UNT Digital Library
Field Testing of the COTS DESI/DART-MS/MS System Against High Explosives Residues (open access)

Field Testing of the COTS DESI/DART-MS/MS System Against High Explosives Residues

None
Date: August 9, 2013
Creator: Alcaraz, A.
Object Type: Report
System: The UNT Digital Library
Algorithm for Screening Phasor Measurement Unit Data for Power System Events and Categories and Common Characteristics for Events Seen in Phasor Measurement Unit Relative Phase-Angle Differences and Frequency Signals (open access)

Algorithm for Screening Phasor Measurement Unit Data for Power System Events and Categories and Common Characteristics for Events Seen in Phasor Measurement Unit Relative Phase-Angle Differences and Frequency Signals

A network of multiple phasor measurement units (PMU) was created, set up, and maintained at the University of Texas at Austin to obtain actual power system measurements for power system analysis. Power system analysis in this report covers a variety of time ranges, such as short- term analysis for power system disturbances and their effects on power system behavior and long- term power system behavior using modal analysis. The first objective of this report is to screen the PMU data for events. The second objective of the report is to identify and describe common characteristics extracted from power system events as measured by PMUs. The numerical characteristics for each category and how these characteristics are used to create selection rules for the algorithm are also described. Trends in PMU data related to different levels and fluctuations in wind power output are also examined.
Date: August 1, 2013
Creator: Allen, A.; Santoso, S. & Muljadi, E.
Object Type: Report
System: The UNT Digital Library
"INDEPENDENT CONFIRMATORY SURVEY SUMMARY AND RESULTS FOR THE FORD NUCLEAR REACTOR, REVISION 1, ANN ARBOR, MICHIGAN (open access)

"INDEPENDENT CONFIRMATORY SURVEY SUMMARY AND RESULTS FOR THE FORD NUCLEAR REACTOR, REVISION 1, ANN ARBOR, MICHIGAN

At the NRC�s request, ORAU conducted confirmatory surveys of the FNR during the period of December 4 through 6, 2012. The survey activities included visual inspections and measurement and sampling activities. Confirmatory activities also included the review and assessment of UM�s project documentation and methodologies. Surface scans identified elevated activity in two areas. The first area was on a wall outside of Room 3103 and the second area was in the southwest section on the first floor. The first area was remediated to background levels. However, the second area was due to gamma shine from a neighboring source storage area. A retrospective analysis of UM�s FSS data shows that for the SUs investigated by the ORAU survey team, UM met the survey requirements set forth in the FSSP. The total mean surface activity values were directly compared with the mean total surface activity reported by UM. Mean surface activity values determined by UM were within two standard deviations of the mean determined by ORAU. Additionally, all surface activity values were less than the corresponding gross beta DCGL{sub W}. Laboratory analysis of the soil showed that COC concentrations were less than the respective DCGL{sub W} values. For the inter-lab comparison, the …
Date: August 1, 2013
Creator: Altic, Nick A.
Object Type: Report
System: The UNT Digital Library
Photoproduction and Decay of Light Mesons in CLAS (open access)

Photoproduction and Decay of Light Mesons in CLAS

We present preliminary experimental results on photoproduction and decay of light mesons measured with CLAS setup at JLAB . This include Dalitz decay of pseudoscalar and vector mesons, radiative decay of pseudoscalar mesons as well hadronic decays of pseudoscalar and vector mesons. The collected high statistics in some of decay channels exceeds the world data by an order of magnitude and some other decay modes are observed for the first time. It is shown how the CLAS data will improve the world data on transition form factors of light mesons, Dalitz plot analyses, branching ratios of rare decay modes and other fundamental properties potentially accessible through the light meson decays.
Date: August 1, 2013
Creator: Amaryan, Moskov Jamalovich
Object Type: Article
System: The UNT Digital Library
Rugby Hohlraum Campaign on the National Ignition (open access)

Rugby Hohlraum Campaign on the National Ignition

None
Date: August 30, 2013
Creator: Amendt, P
Object Type: Article
System: The UNT Digital Library
Technical Readiness and Gaps Analysis of Commercial Optical Materials and Measurement Systems for Advanced Small Modular Reactors (open access)

Technical Readiness and Gaps Analysis of Commercial Optical Materials and Measurement Systems for Advanced Small Modular Reactors

This report intends to support Department of Energy’s Office of Nuclear Energy (DOE-NE) Nuclear Energy Research and Development Roadmap and industry stakeholders by evaluating optical-based instrumentation and control (I&C) concepts for advanced small modular reactor (AdvSMR) applications. These advanced designs will require innovative thinking in terms of engineering approaches, materials integration, and I&C concepts to realize their eventual viability and deployability. The primary goals of this report include: 1. Establish preliminary I&C needs, performance requirements, and possible gaps for AdvSMR designs based on best available published design data. 2. Document commercial off-the-shelf (COTS) optical sensors, components, and materials in terms of their technical readiness to support essential AdvSMR in-vessel I&C systems. 3. Identify technology gaps by comparing the in-vessel monitoring requirements and environmental constraints to COTS optical sensor and materials performance specifications. 4. Outline a future research, development, and demonstration (RD&D) program plan that addresses these gaps and develops optical-based I&C systems that enhance the viability of future AdvSMR designs. The development of clean, affordable, safe, and proliferation-resistant nuclear power is a key goal that is documented in the Nuclear Energy Research and Development Roadmap. This roadmap outlines RD&D activities intended to overcome technical, economic, and other barriers, which currently …
Date: August 6, 2013
Creator: Anheier, Norman C.; Suter, Jonathan D.; Qiao, Hong (Amy); Andersen, Eric S.; Berglin, Eric J.; Bliss, Mary et al.
Object Type: Report
System: The UNT Digital Library
Presentations by MIIS-LLNL Safeguards Policy Interns (open access)

Presentations by MIIS-LLNL Safeguards Policy Interns

None
Date: August 19, 2013
Creator: Anzelon, G. A.; Davydov, J. S.; Park, K. K.; McCarthy, K. T.; Kuwata, Y. A. & Wilbourne, J. L.
Object Type: Report
System: The UNT Digital Library
Humidity effects on wire insulation breakdown strength. (open access)

Humidity effects on wire insulation breakdown strength.

Methods for the testing of the dielectric breakdown strength of insulation on metal wires under variable humidity conditions were developed. Two methods, an ASTM method and the twisted pair method, were compared to determine if the twisted pair method could be used for determination of breakdown strength under variable humidity conditions. It was concluded that, although there were small differences in outcomes between the two testing methods, the non-standard method (twisted pair) would be appropriate to use for further testing of the effects of humidity on breakdown performance. The dielectric breakdown strength of 34G copper wire insulated with double layer Poly-Thermaleze/Polyamide-imide insulation was measured using the twisted pair method under a variety of relative humidity (RH) conditions and exposure times. Humidity at 50% RH and below was not found to affect the dielectric breakdown strength. At 80% RH the dielectric breakdown strength was significantly diminished. No effect for exposure time up to 140 hours was observed at 50 or 80%RH.
Date: August 1, 2013
Creator: Appelhans, Leah
Object Type: Report
System: The UNT Digital Library
Non-Hardware ("Soft") Cost-Reduction Roadmap for Residential and Small Commercial Solar Photovoltaics, 2013-2020 (open access)

Non-Hardware ("Soft") Cost-Reduction Roadmap for Residential and Small Commercial Solar Photovoltaics, 2013-2020

The objective of this analysis is to roadmap the cost reductions and innovations necessary to achieve the U.S. Department of Energy (DOE) SunShot Initiative's total soft-cost targets by 2020. The roadmap focuses on advances in four soft-cost areas: (1) customer acquisition; (2) permitting, inspection, and interconnection (PII); (3) installation labor; and (4) financing. Financing cost reductions are in terms of the weighted average cost of capital (WACC) for financing PV system installations, with real-percent targets of 3.0% (residential) and 3.4% (commercial).
Date: August 1, 2013
Creator: Ardani, K.; Seif, D.; Margolis, R.; Morris, J.; Davidson, C.; Truitt, S. et al.
Object Type: Report
System: The UNT Digital Library
The LTS timing analysis program : user%3CU%2B2019%3Es manual and description of the methods of analysis. (open access)

The LTS timing analysis program : user%3CU%2B2019%3Es manual and description of the methods of analysis.

The LTS Timing Analysis program described in this report uses signals from the Tempest Lasers, Pulse Forming Lines, and Laser Spark Detectors to carry out calculations to quantify and monitor the performance of the the Z-Accelerator's laser triggered SF6 switches. The program analyzes Z-shots beginning with Z2457, when Laser Spark Detector data became available for all lines.
Date: August 1, 2013
Creator: Armstrong, Darrell Jewell & Schwarz, Jens
Object Type: Report
System: The UNT Digital Library
Analysis of Daylighting Requirements within ASHRAE Standard 90.1 (open access)

Analysis of Daylighting Requirements within ASHRAE Standard 90.1

Pacific Northwest National Laboratory (PNNL), under the Building Energy Codes Program (BECP) funded by U.S. Department of Energy (DOE), provides support to the ASHRAE/IES/IESNA Standard 90.1(Standard 90.1) Standing Standards Project Committee (SSPC 90.1) and its subcommittees. In an effort to provide the ASHRAE SSPC 90.1 with data that will improve the daylighting and fenestration requirements in the Standard, PNNL collaborated with Heschong Mahone Group (HMG), now part of TRC Solutions. Combining EnergyPlus, a whole-building energy simulation software developed by DOE, with Radiance, a highly accurate illumination modeling software (Ward 1994), the daylighting requirements within Standard 90.1 were analyzed in greater detail. The initial scope of the study was to evaluate the impact of the fraction of window area compared to exterior wall area (window-to-wall ratio (WWR)) on energy consumption when daylighting controls are implemented. This scope was expanded to study the impact of fenestration visible transmittance (VT), electric lighting controls and daylighted area on building energy consumption.
Date: August 1, 2013
Creator: Athalye, Rahul A.; Xie, YuLong; Liu, Bing & Rosenberg, Michael I.
Object Type: Report
System: The UNT Digital Library
Monte Carlo Simulation of Neutron Noise Effects on Beam Position Determination With Real and Simulated Beam Images at the National Ignition Facility (open access)

Monte Carlo Simulation of Neutron Noise Effects on Beam Position Determination With Real and Simulated Beam Images at the National Ignition Facility

None
Date: August 27, 2013
Creator: Awwal, A.; Leach, R.; Datte, P. & Manuel, A.
Object Type: Article
System: The UNT Digital Library
Design and implementation of Dilation X-ray Imager for National Ignition Facility "DIXI" (open access)

Design and implementation of Dilation X-ray Imager for National Ignition Facility "DIXI"

None
Date: August 22, 2013
Creator: Ayers, M. J.; Bell, P. M.; Bradley, D.; Chung, M.; Felker, B.; Hares, J. et al.
Object Type: Article
System: The UNT Digital Library