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Madill Subdivision Bridge, Dallas, Texas: Determination of National Register Eligibility (open access)

Madill Subdivision Bridge, Dallas, Texas: Determination of National Register Eligibility

Preliminary report assessing the eligibility for inclusion in the national Register of Historic Places (NRHP) of Railroad Bridge 705.20 on the Burlington Northern Santa Fe Railway (BNSF) Madill Subdivision. It includes a historical summary of the railroad alignment and photographs of the bridge. The authors concluded that the bridge was not historically significant, as it was typical of railroad bridges of the late 20th century and had been modified several times.
Date: May 8, 2013
Creator: DeFreece Emery, Sherry N. & Singleton, Kate
System: The Portal to Texas History
South Oak Cliff (SOC-3) Blue Line Extension in Dallas County, Texas: Final Local Environmental Assessment (open access)

South Oak Cliff (SOC-3) Blue Line Extension in Dallas County, Texas: Final Local Environmental Assessment

This Local Environmental Assessment (LEA) describes the transportation and environmental impacts associated with the construction and operation of a proposed, 2.6-mile light rail extension from Ledbetter Station to the UNT Dallas campus and identifies mitigation measures. This Final LEA is based on the 5% level of design and includes responses to comments received during the 30-day public review period for the Draft LEA.
Date: May 2013
Creator: Dallas Area Rapid Transit
System: The Portal to Texas History
The President's Malaria Initiative: Seventh Annual Report to Congress (open access)

The President's Malaria Initiative: Seventh Annual Report to Congress

A report about combating malaria in Africa. It offers statistics and methods used for fighting malaria.
Date: May 2013
Creator: United State. Agency for International Development.
System: The UNT Digital Library
Tracking Adaptation Efforts (open access)

Tracking Adaptation Efforts

A presentation about global warming and implementing changes to mitigate climate change.
Date: May 1, 2013
Creator: Burgess, Scott
System: The UNT Digital Library
User's Guide and Metadata for WestuRe: U.S. Pacific Coast Estuary/Watershed Data and R Tools (open access)

User's Guide and Metadata for WestuRe: U.S. Pacific Coast Estuary/Watershed Data and R Tools

A report about the WestuRe Project. The goal of this project is to create a framework to make general descriptive data for estuaries and their watersheds more accessible. It also aims to provide tools to make analyzing and visualizing this data easier.
Date: May 2013
Creator: Frazier, D.A.; Ruesser, D. A.; Lee II, H.; McCoy, L. M.; Brown, C. & Nelson, W.
System: The UNT Digital Library
Integrating Adaptation in Hazard Mitigation Planning Efforts (open access)

Integrating Adaptation in Hazard Mitigation Planning Efforts

A presentation that discusses the NHMA, hazard mitigation, challenges of mitigation, examples of hazard prevention, and funding that can be used.
Date: May 1, 2013
Creator: Klima, Kelly & Jerolleman, Alessandra
System: The UNT Digital Library
Site Environmental Report for 2012 Sandia National Laboratories California. (open access)

Site Environmental Report for 2012 Sandia National Laboratories California.

None
Date: May 1, 2013
Creator: Larsen, Barbara L.
System: The UNT Digital Library
Nuclear Fuel Cycle Reasoner: PNNL FY12 Report (open access)

Nuclear Fuel Cycle Reasoner: PNNL FY12 Report

Building on previous internal investments and leveraging ongoing advancements in semantic technologies, PNNL implemented a formal reasoning framework and applied it to a specific challenge in nuclear nonproliferation. The Semantic Nonproliferation Analysis Platform (SNAP) was developed as a preliminary graphical user interface to demonstrate the potential power of the underlying semantic technologies to analyze and explore facts and relationships relating to the nuclear fuel cycle (NFC). In developing this proof of concept prototype, the utility and relevancy of semantic technologies to the Office of Defense Nuclear Nonproliferation Research and Development (DNN R&D) has been better understood.
Date: May 3, 2013
Creator: Hohimer, Ryan E.; Pomiak, Yekaterina G.; Neorr, Peter A.; Gastelum, Zoe N. & Strasburg, Jana D.
System: The UNT Digital Library
Efficient Regeneration of Physical and Chemical Solvents for CO{sub 2} Capture (open access)

Efficient Regeneration of Physical and Chemical Solvents for CO{sub 2} Capture

The objective of this project was to evaluate the use of composite polymer membranes and porous membrane contactors to regenerate physical and chemical solvents for capture of carbon dioxide (CO{sub 2}) from synthesis gas or flue gas, with the goal of improving the energy efficiency of carbon capture. Both a chemical solvent (typical for a post-combustion capture of CO{sub 2} from flue gas) and a physical solvent (typical for pre- combustion capture of CO{sub 2} from syngas) were evaluated using two bench-scale test systems constructed for this project. For chemical solvents, polytetrafluoroethylene and polypropylene membranes were found to be able to strip CO{sub 2} from a monoethanolamine (MEA) solution with high selectivity without significant degradation of the material. As expected, the regeneration temperature was the most significant parameter affecting the CO{sub 2} flux through the membrane. Pore size was also found to be important, as pores larger than 5 microns lead to excessive pore wetting. For physical solvents, polydimethyl-siloxane (PDMS)-based membranes were found to have a higher CO{sub 2} permeability than polyvinylalcohol (PVOH) based membranes, while also minimizing solvent loss. Overall, however, the recovery of CO{sub 2} in these systems is low – less than 2% for both chemical and …
Date: May 31, 2013
Creator: Tande, Brian; Seames, Wayne & Benson, Steve
System: The UNT Digital Library
Feynman variance for neutrons emitted from photo-fission initiated fission chains - a systematic simulation for selected speacal nuclear materials (open access)

Feynman variance for neutrons emitted from photo-fission initiated fission chains - a systematic simulation for selected speacal nuclear materials

None
Date: May 14, 2013
Creator: Soltz, R; Hartouni, E; Sheets, S & Glenn, A
System: The UNT Digital Library
Supplemental Immobilization Cast Stone Technology Development and Waste Form Qualification Testing Plan (open access)

Supplemental Immobilization Cast Stone Technology Development and Waste Form Qualification Testing Plan

The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the 56 million gallons of radioactive waste stored in 177 underground tanks at the Hanford Site. The WTP includes a pretreatment facility to separate the wastes into high-level waste (HLW) and low-activity waste (LAW) fractions for vitrification and disposal. The LAW will be converted to glass for final disposal at the Integrated Disposal Facility (IDF). The pretreatment facility will have the capacity to separate all of the tank wastes into the HLW and LAW fractions, and the HLW Vitrification Facility will have the capacity to vitrify all of the HLW. However, a second immobilization facility will be needed for the expected volume of LAW requiring immobilization. A number of alternatives, including Cast Stone—a cementitious waste form—are being considered to provide the additional LAW immobilization capacity.
Date: May 31, 2013
Creator: Westsik, Joseph H.; Serne, R. Jeffrey; Pierce, Eric M.; Cozzi, Alex; Chung, Chul-Woo & Swanberg, David J.
System: The UNT Digital Library
CO{sub 2} Geologic Storage: Coupled Hydro-Chemo-Thermo-Mechanical Phenomena - From Pore-scale Processes to Macroscale Implications - (open access)

CO{sub 2} Geologic Storage: Coupled Hydro-Chemo-Thermo-Mechanical Phenomena - From Pore-scale Processes to Macroscale Implications -

Global energy consumption will increase in the next decades and it is expected to largely rely on fossil fuels. The use of fossil fuels is intimately related to CO{sub 2} emissions and the potential for global warming. Geological CO{sub 2} storage aims to mitigate the global warming problem by sequestering CO{sub 2} underground. Coupled hydro-chemo-mechanical phenomena determine the successful operation and long term stability of CO{sub 2} geological storage. This research explores coupled phenomena, identifies different zones in the storage reservoir, and investigates their implications in CO{sub 2} geological storage. In particular, the research: Explores spatial patterns in mineral dissolution and precipitation (comprehensive mass balance formulation); experimentally determines the interfacial properties of water, mineral, and CO{sub 2} systems (including CO{sub 2}-water-surfactant mixtures to reduce the CO{sub 2}- water interfacial tension in view of enhanced sweep efficiency); analyzes the interaction between clay particles and CO{sub 2}, and the response of sediment layers to the presence of CO{sub 2} using specially designed experimental setups and complementary analyses; couples advective and diffusive mass transport of species, together with mineral dissolution to explore pore changes during advection of CO{sub 2}-dissolved water along a rock fracture; upscales results to a porous medium using pore network …
Date: May 31, 2013
Creator: Santamarina, J. Carlos
System: The UNT Digital Library
Risks from Past, Current, and Potential Hanford Single Shell Tank Leaks (open access)

Risks from Past, Current, and Potential Hanford Single Shell Tank Leaks

Due to significant delays in constructing and operating the Waste Treatment Plant, which is needed to support retrieval of waste from Hanford’s single shell tanks (SSTs), SSTs may now be required to store tank waste for two to three more decades into the future. Many SSTs were built almost 70 years ago, and all SSTs are well beyond their design lives. Recent examination of monitoring data suggests several of the tanks, which underwent interim stabilization a decade or more ago, may be leaking small amounts (perhaps 150–300 gallons per year) to the subsurface environment. A potential leak from tank T-111 is estimated to have released approximately 2,000 gallons into the subsurface. Observations of past leak events, recently published simulation results, and new simulations all suggest that recent leaks are unlikely to affect underlying groundwater above regulatory limits. However, these recent observations remind us that much larger source terms are still contained in the tanks and are also present in the vadose zone from historical intentional and unintentional releases. Recently there have been significant improvements in methods for detecting and characterizing soil moisture and contaminant releases, understanding and controlling mass-flux, and remediating deep vadose zone and groundwater plumes. To ensure extended …
Date: May 24, 2013
Creator: Triplett, Mark B.; Watson, David J. & Wellman, Dawn M.
System: The UNT Digital Library
Improved Flow-Field Structures for Direct Methanol Fuel Cells (open access)

Improved Flow-Field Structures for Direct Methanol Fuel Cells

The direct methanol fuel cell (DMFC) is ideal if high energy-density liquid fuels are required. Liquid fuels have advantages over compressed hydrogen including higher energy density and ease of handling. Although state-of-the-art DMFCs exhibit manageable degradation rates, excessive fuel crossover diminishes system energy and power density. Although use of dilute methanol mitigates crossover, the concomitant lowering of the gross fuel energy density (GFED) demands a complex balance-of-plant (BOP) that includes higher flow rates, external exhaust recirculation, etc. An alternative approach is redesign of the fuel delivery system to accommodate concentrated methanol. NuVant Systems Inc. (NuVant) will maximize the GFED by design and assembly of a DMFC that uses near neat methanol. The approach is to tune the diffusion of highly concentrated methanol (to the anode catalytic layer) to the back-diffusion of water formed at the cathode (i.e. in situ generation of dilute methanol at the anode layer). Crossover will be minimized without compromising the GFED by innovative integration of the anode flow-field and the diffusion layer. The integrated flow-field-diffusion-layers (IFDLs) will widen the current and potential DMFC operating ranges and enable the use of cathodes optimized for hydrogen-air fuel cells.
Date: May 31, 2013
Creator: Gurau, Bogdan
System: The UNT Digital Library
Dynamic Line Rating Oncor Electric Delivery Smart Grid Program (open access)

Dynamic Line Rating Oncor Electric Delivery Smart Grid Program

Electric transmission lines are the lifeline of the electric utility industry, delivering its product from source to consumer. This critical infrastructure is often constrained such that there is inadequate capacity on existing transmission lines to efficiently deliver the power to meet demand in certain areas or to transport energy from high-generation areas to high-consumption regions. When this happens, the cost of the energy rises; more costly sources of power are used to meet the demand or the system operates less reliably. These economic impacts are known as congestion, and they can amount to substantial dollars for any time frame of reference: hour, day or year. There are several solutions to the transmission constraint problem, including: construction of new generation, construction of new transmission facilities, rebuilding and reconductoring of existing transmission assets, and Dynamic Line Rating (DLR). All of these options except DLR are capital intensive, have long lead times and often experience strong public and regulatory opposition. The Smart Grid Demonstration Program (SGDP) project co-funded by the Department of Energy (DOE) and Oncor Electric Delivery Company developed and deployed the most extensive and advanced DLR installation to demonstrate that DLR technology is capable of resolving many transmission capacity constraint problems …
Date: May 4, 2013
Creator: Johnson, Justin; Smith, Cale; Young, Mike; Donohoo, Ken; Owen, Ross; Clark, Eddit et al.
System: The UNT Digital Library
Recovery Act: Multi-Objective Optimization Approaches for the Design of Carbon Geological Sequestration Systems (open access)

Recovery Act: Multi-Objective Optimization Approaches for the Design of Carbon Geological Sequestration Systems

The main objective of this project is to provide training opportunities for two graduate students in order to improve the human capital and skills required for implementing and deploying carbon capture and sequestration (CCS) technologies. The graduate student effort will be geared towards the formulation and implementation of an integrated simulation-optimization framework to provide a rigorous scientific support to the design CCS systems that, for any given site: (a) maximize the amount of carbon storage; (b) minimize the total cost associated with the CCS project; (c) minimize the risk of CO2 upward leakage from injected formations. The framework will stem from a combination of data obtained from geophysical investigations, a multiphase flow model, and a stochastic multi-objective optimization algorithm. The methodology will rely on a geostatistical approach to generate ensembles of scenarios of the parameters that are expected to have large sensitivities and uncertainties on the model response and thus on the risk assessment, in particular the permeability properties of the injected formation and its cap rock. The safety theme will be addressed quantitatively by including the risk of CO2 upward leakage from the injected formations as one the objectives that should be minimized in the optimization problem. The research …
Date: May 31, 2013
Creator: Bau, Domenico
System: The UNT Digital Library
Partial Return Yoke for MICE (open access)

Partial Return Yoke for MICE

The international Muon Ionization Cooling Experiment (MICE) is a large scale experiment which is presently assembled at the Rutherford Appleton Laboratory in Didcot, UK. The purpose of MICE is to demonstrate the concept of ionization cooling experimentally. Ionization cooling is an important accelerator concept which will be essential for future HEP experiments such as a potential Muon Collider or a Neutrino Factory. The MICE experiment will house up to 18 superconducting solenoids, all of which produce a substantial amount of magnetic flux. Recently it was realized that this magnetic flux leads to a considerable stray magnetic field in the MICE hall. This is a concern as technical equipment in the MICE hall may may be compromised by this. In July 2012 a concept called partial return yoke was presented to the MICE community, which reduces the stray field in the MICE hall to a safe level. This report summarizes the general concept, engineering considerations and the expected shielding performance.
Date: May 3, 2013
Creator: Witte, Holger & Plate, Stephen
System: The UNT Digital Library
Effects of Electromagnetic Fields on Fish and Invertebrates Task 2.1.3: Effects on Aquatic Organisms Fiscal Year 2012 Progress Report Environmental Effects of Marine and Hydrokinetic Energy (open access)

Effects of Electromagnetic Fields on Fish and Invertebrates Task 2.1.3: Effects on Aquatic Organisms Fiscal Year 2012 Progress Report Environmental Effects of Marine and Hydrokinetic Energy

Energy generated by the world’s oceans and rivers offers the potential to make substantial contributions to the domestic and global renewable energy supply. However, the marine and hydrokinetic (MHK) energy industry faces challenges related to siting, permitting, construction, and operation of pilotand commercial-scale facilities. One of the challenges is to understand the potential effects to marine organisms from electromagnetic fields, which are produced as a by-product of transmitting power from offshore to onshore locations through underwater transmission cables. This report documents the progress of the third year of research (fiscal year 2012) to investigate environmental issues associated with marine and hydrokinetic energy (MHK) generation. This work was conducted by Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy’s (DOE’s) Office of Energy Efficiency and Renewable Energy (EERE) Wind and Water Technologies Office. The report addresses the effects of electromagnetic fields (EMFs) on selected marine species where significant knowledge gaps exist. The species studied this fiscal year included one fish and two crustacean species: the Atlantic halibut (Hippoglossus hippoglossus), Dungeness crab (Metacarcinus magister), and American lobster (Homarus americanus).
Date: May 20, 2013
Creator: Woodruff, Dana L.; Cullinan, Valerie I.; Copping, Andrea E. & Marshall, Kathryn E.
System: The UNT Digital Library
A NMR-Based Carbon-Type Analysis of Diesel Fuel Blends From Various Sources (open access)

A NMR-Based Carbon-Type Analysis of Diesel Fuel Blends From Various Sources

In collaboration with participants of the Coordinating Research Council (CRC) Advanced Vehicle/Fuels/Lubricants (AVFL) Committee, and project AVFL-19, the characteristics of fuels from advanced and renewable sources were compared to commercial diesel fuels. The main objective of this study was to highlight similarities and differences among the fuel types, i.e. ULSD, renewables, and alternative fuels, and among fuels within the different fuel types. This report summarizes the carbon-type analysis from 1H and 13C{1H} nuclear magnetic resonance spectroscopy (NMR) of 14 diesel fuel samples. The diesel fuel samples come from diverse sources and include four commercial ultra-low sulfur diesel fuels (ULSD), one gas-to-liquid diesel fuel (GTL), six renewable diesel fuels (RD), two shale oil-derived diesel fuels, and one oil sands-derived diesel fuel. Overall, the fuels examined fall into two groups. The two shale oil-derived samples and the oil-sand-derived sample closely resemble the four commercial ultra-low sulfur diesels, with SO1 and SO2 most closely matched with ULSD1, ULSD2, and ULSD4, and OS1 most closely matched with ULSD3. As might be expected, the renewable diesel fuels, with the exception of RD3, do not resemble the ULSD fuels because of their very low aromatic content, but more closely resemble the gas-to-liquid sample (GTL) in this …
Date: May 10, 2013
Creator: Bays, J. Timothy & King, David L.
System: The UNT Digital Library
Investigation on Flame Characteristics and Burner Operability Issues of Oxy-Fuel Combustion (open access)

Investigation on Flame Characteristics and Burner Operability Issues of Oxy-Fuel Combustion

Oxy-fuel combustion has been used previously in a wide range of industrial applications. Oxy- combustion is carried out by burning a hydrocarbon fuel with oxygen instead of air. Flames burning in this configuration achieve higher flame temperatures which present opportunities for significant efficiency improvements and direct capture of CO{sub 2} from the exhaust stream. In an effort to better understand and characterize the fundamental flame characteristics of oxy-fuel combustion this research presents the experimental measurements of flame stability of various oxyfuel flames. Effects of H{sub 2} concentration, fuel composition, exhaust gas recirculation ratio, firing inputs, and burner diameters on the flame stability of these fuels are discussed. Effects of exhaust gas recirculation i.e. CO{sub 2} and H{sub 2}O (steam) acting as diluents on burner operability are also presented. The roles of firing input on flame stability are then analyzed. For this study it was observed that many oxy-flames did not stabilize without exhaust gas recirculation due to their higher burning velocities. In addition, the stability regime of all compositions was observed to decrease as the burner diameter increased. A flashback model is also presented, using the critical velocity gradient g{sub F}) values for CH{sub 4}-O{sub 2}-CO{sub 2} flames. The scaling …
Date: May 30, 2013
Creator: Choudhuri, Ahsan
System: The UNT Digital Library
Rock Physics of Geologic Carbon Sequestration/Storage (open access)

Rock Physics of Geologic Carbon Sequestration/Storage

This report covers the results of developing the rock physics theory of the effects of CO{sub 2} injection and storage in a host reservoir on the rock�s elastic properties and the resulting seismic signatures (reflections) observed during sequestration and storage. Specific topics addressed are: (a) how the elastic properties and attenuation vary versus CO{sub 2} saturation in the reservoir during injection and subsequent distribution of CO{sub 2} in the reservoir; (b) what are the combined effects of saturation and pore pressure on the elastic properties; and (c) what are the combined effects of saturation and rock fabric alteration on the elastic properties. The main new results are (a) development and application of the capillary pressure equilibrium theory to forecasting the elastic properties as a function of CO{sub 2} saturation; (b) a new method of applying this theory to well data; and (c) combining this theory with other effects of CO{sub 2} injection on the rock frame, including the effects of pore pressure and rock fabric alteration. An important result is translating these elastic changes into synthetic seismic responses, specifically, the amplitude-versus-offset (AVO) response depending on saturation as well as reservoir and seal type. As planned, three graduate students participated in …
Date: May 31, 2013
Creator: Dvorkin, Jack & Mavko, Gary
System: The UNT Digital Library
Advances in Hydrogeochemical Indicators for the Discovery of New Geothermal Resources in the Great Basin, USA (open access)

Advances in Hydrogeochemical Indicators for the Discovery of New Geothermal Resources in the Great Basin, USA

This report summarizes the results of Phase I work for a go/no go decision on Phase II funding. In the first objective, we assessed the extent to which fluid-mineral equilibria controlled deep water compositions in geothermal systems across the Great Basin. Six systems were evaluated: Beowawe; Desert Peak; Dixie Valley; Mammoth; Raft River; Roosevelt. These represent a geographic spread of geothermal resources, in different geological settings and with a wide range of fluid compositions. The results were used for calibration/reformulation of chemical geothermometers that reflect the reservoir temperatures in producing reservoirs. In the second objective, we developed a reactive -transport model of the Desert Peak hydrothermal system to evaluate the processes that affect reservoir fluid geochemistry and its effect on solute geothermometry. This included testing geothermometry on “reacted” thermal water originating from different lithologies and from near-surface locations where the temperature is known from the simulation. The integrated multi-component geothermometer (GeoT, relying on computed mineral saturation indices) was tested against the model results and also on the systems studied in the first objective.
Date: May 20, 2013
Creator: Simmons, Stuart F.; Spycher, Nicolas; Sonnenthal, Eric & Dobson, Patrick
System: The UNT Digital Library
JSATS Decoder Software Manual (open access)

JSATS Decoder Software Manual

The Juvenile Salmon Acoustic Telemetry System (JSATS) Decoder is a software application that converts a digitized acoustic signal (a waveform stored in the .bwm file format) into a list of potential JSATS Acoustic MicroTransmitter (AMT) tagcodes along with other data about the signal including time of arrival and signal to noise ratios (SNR). This software is capable of decoding single files, directories, and viewing raw acoustic waveforms. When coupled with the JSATS Detector, the Decoder is capable of decoding in ‘real-time’ and can also provide statistical information about acoustic beacons placed within receive range of hydrophones within a JSATS array. This document details the features and functionality of the software. The document begins with software installation instructions (section 2), followed in order by instructions for decoder setup (section 3), decoding process initiation (section 4), then monitoring of beacons (section 5) using real-time decoding features. The last section in the manual describes the beacon, beacon statistics, and the results file formats. This document does not consider the raw binary waveform file format.
Date: May 1, 2013
Creator: Flory, Adam E.; Lamarche, Brian L. & Weiland, Mark A.
System: The UNT Digital Library
A Python Object Oriented & Data Driven Testing Infrastructure for an Environmental Information Management System (open access)

A Python Object Oriented & Data Driven Testing Infrastructure for an Environmental Information Management System

None
Date: May 1, 2013
Creator: Barbosa, E & Laguna, G W
System: The UNT Digital Library