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Berlin's History in Context: The Foreign Ministry and the Spreebogen Complex in the Context of the Architectural Debates

Access: Use of this item is restricted to the UNT Community
Book chapter discussing Berlin, Germany's history in context and the Foreign Ministry and Spreebogen Complex in the context of the architectural debates.
Date: October 1, 2011
Creator: Costabile-Heming, Carol Anne
Object Type: Book Chapter
System: The UNT Digital Library
Bessel-Weighted Asymmetries in Semi Inclusive Deep Inelastic Scattering (open access)

Bessel-Weighted Asymmetries in Semi Inclusive Deep Inelastic Scattering

The concept of weighted asymmetries is revisited for semi-inclusive deep inelastic scattering. We consider the cross section in Fourier space, conjugate to the outgoing hadron's transverse momentum, where convolutions of transverse momentum dependent parton distribution functions and fragmentation functions become simple products. Individual asymmetric terms in the cross section can be projected out by means of a generalized set of weights involving Bessel functions. Advantages of employing these Bessel weights are that they suppress (divergent) contributions from high transverse momentum and that soft factors cancel in (Bessel-) weighted asymmetries. Also, the resulting compact expressions immediately connect to previous work on evolution equations for transverse momentum dependent parton distribution and fragmentation functions and to quantities accessible in lattice QCD. Bessel weighted asymmetries are thus model independent observables that augment the description and our understanding of correlations of spin and momentum in nucleon structure.
Date: October 1, 2011
Creator: D. Boer, L. Gamberg, B.U. Musch, A. Prokudin
Object Type: Article
System: The UNT Digital Library
Biomass in Multifunction Crop Plants: Cooperative Research and Development Final Report, CRADA Number CRD-05-163 (open access)

Biomass in Multifunction Crop Plants: Cooperative Research and Development Final Report, CRADA Number CRD-05-163

An array of cellulase, hemicellulase, and accessory enzymes were tested for their ability to increase the conversion levels and rates of biomass to sugar after being subjected to thermochemical pretreatment. The genes were cloned by Oklahoma State University and expressed, purified, and tested at NREL. Several enzymes were noted to be effective in increasing conversion levels, however expression levels were typically very low. The overall plan was to express these enzymes in corn as a possible mechanism towards decreased recalcitrance. One enzyme, cel5A endoglucanase from Acidothermus cellulolyticus, was transformed into both tobacco and corn. The transgenic corn stover and tobacco were examined for their susceptibility to thermochemical pretreatment followed by enzymatic digestion.
Date: October 1, 2011
Creator: Decker, S. R.
Object Type: Report
System: The UNT Digital Library
Boston, Massachusetts: Solar in Action (Brochure) (open access)

Boston, Massachusetts: Solar in Action (Brochure)

This brochure provides an overview of the challenges and successes of Boston, MA, a 2007 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given. The City of Boston and its Solar America Cities program, Solar Boston, are helping to debunk the myth that solar energy is only feasible in the southern latitudes. Boston has some of the highest energy prices in the country and will likely be one of the first locations where solar power achieves grid parity with conventional energy technologies. Solar Boston is facilitating the rapid development of solar energy projects and infrastructure in the short-term, and is preparing for the rapid market growth that is expected with the imminent arrival of grid parity over the long-term. Solar Boston developed the strategy for achieving Mayor Menino's goal of installing 25 MW of solar energy throughout Boston by 2015. Through Solar Boston, the city has developed a strategy for the installation of solar technology throughout Boston, including mapping feasible locations, preparing a permitting guide, and planning the citywide bulk purchase, financing, and installation of solar technology. The city has also worked with local organizations …
Date: October 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Building America Expert Meeting Report: Hydronic Heating in Multifamily Buildings (open access)

Building America Expert Meeting Report: Hydronic Heating in Multifamily Buildings

The topic of this expert meeting was cost-effective controls and distribution retrofit options for hot water and steam space heating systems in multi-family buildings with the goals of reducing energy waste and improving occupant comfort. The U.S. Department of Energy's Building America program develops technologies with the goal of reducing energy use by 30% to 50% in residential buildings. Toward this goal, the program sponsors 'Expert Meetings' focused on specific building technology topics. The meetings are intended to sharpen Building America research priorities, create a forum for sharing information among industry leaders and build partnerships with professionals and others that can help support the program's research needs and objectives. The topic of this expert meeting was cost-effective controls and distribution retrofit options for hot water and steam space heating systems in multifamily buildings with the goals of reducing energy waste and improving occupant comfort. The objectives of the meeting were to: (1) Share knowledge and experience on new and existing solutions: what works, what doesn't and why, and what's new; (2) Understand the market barriers to currently offered solutions: what disconnects exist in the market and what is needed to overcome or bridge these gaps; and (3) Identify research needs.
Date: October 1, 2011
Creator: Dentz, J.
Object Type: Report
System: The UNT Digital Library
Building America Expert Meeting Report: Transitioning Traditional HVAC Contractors to Whole House Performance Contractors (open access)

Building America Expert Meeting Report: Transitioning Traditional HVAC Contractors to Whole House Performance Contractors

This report outlines findings resulting from a U.S. Department of Energy Building America expert meeting to determine how HVAC companies can transition from a traditional contractor status to a service provider for whole house energy upgrade contracting. IBACOS has embarked upon a research effort under the Building America Program to understand business impacts and change management strategies for HVAC companies. HVAC companies can implement these strategies in order to quickly transition from a 'traditional' heating and cooling contractor to a service provider for whole house energy upgrade contracting. Due to HVAC service contracts, which allow repeat interaction with homeowners, HVAC companies are ideally positioned in the marketplace to resolve homeowner comfort issues through whole house energy upgrades. There are essentially two primary ways to define the routes of transition for an HVAC contractor taking on whole house performance contracting: (1) Sub-contracting out the shell repair/upgrade work; and (2) Integrating the shell repair/upgrade work into their existing business. IBACOS held an Expert Meeting on the topic of Transitioning Traditional HVAC Contractors to Whole House Performance Contractors on March 29, 2011 in San Francisco, CA. The major objectives of the meeting were to: Review and validate the general business models for traditional …
Date: October 1, 2011
Creator: Burdick, A.
Object Type: Report
System: The UNT Digital Library
CAES Annual Report FY 2011 (open access)

CAES Annual Report FY 2011

The Center for Advanced Energy Studies was created to lead research programs important to the nation, attract students and faculty to the Idaho universities and act as a catalyst for technology-based economic development. CAES is striving to meet those goals by continuing to develop its infrastructure and equipment capabilities, expand its research portfolio and bolster Idaho's energy workforce. This Annual Report details the progress CAES made in FY 2011 toward fulfilling its research, education and economic development missions.
Date: October 1, 2011
Creator: Rolston, Kortny
Object Type: Report
System: The UNT Digital Library
Challenges in Simulation of Aerodynamics, Hydrodynamics, and Mooring-Line Dynamics of Floating Offshore Wind Turbines (open access)

Challenges in Simulation of Aerodynamics, Hydrodynamics, and Mooring-Line Dynamics of Floating Offshore Wind Turbines

This paper presents the current major modeling challenges for floating offshore wind turbine design tools and describes aerodynamic and hydrodynamic effects due to rotor and platform motions and usage of non-slender support structures.
Date: October 1, 2011
Creator: Matha, D.; Schlipf, M.; Cordle, A.; Pereira, R. & Jonkman, J.
Object Type: Article
System: The UNT Digital Library
The Christian Chronicle (Oklahoma City, Okla.), Vol. 68, No. 10, Ed. 1 Saturday, October 1, 2011 (open access)

The Christian Chronicle (Oklahoma City, Okla.), Vol. 68, No. 10, Ed. 1 Saturday, October 1, 2011

Monthly newspaper from Oklahoma City, Oklahoma that includes news and information about the Churches of Christ along with advertising.
Date: October 1, 2011
Creator: McMillon, Lynn
Object Type: Newspaper
System: The Portal to Texas History
CHRONIC IRRADIATION OF SCOTS PINE TREES (PINUS SYLVESTRIS) IN THE CHERNOBYL EXCLUSION ZONE: DOSIMETRY AND RADIOBIOLOGICAL EFFECTS (open access)

CHRONIC IRRADIATION OF SCOTS PINE TREES (PINUS SYLVESTRIS) IN THE CHERNOBYL EXCLUSION ZONE: DOSIMETRY AND RADIOBIOLOGICAL EFFECTS

To identify effects of chronic internal and external radiation exposure for components of terrestrial ecosystems, a comprehensive study of Scots pine trees in the Chernobyl Exclusion Zone was performed. The experimental plan included over 1,100 young trees (up to 20 years old) selected from areas with varying levels of radioactive contamination. These pine trees were planted after the 1986 Chernobyl Nuclear Power Plant accident mainly to prevent radionuclide resuspension and soil erosion. For each tree, the major morphological parameters and radioactive contamination values were identified. Cytological analyses were performed for selected trees representing all dose rate ranges. A specially developed dosimetric model capable of taking into account radiation from the incorporated radionuclides in the trees was developed for the apical meristem. The calculated dose rates for the trees in the study varied within three orders of magnitude, from close to background values in the control area (about 5 mGy y{sup -1}) to approximately 7 Gy y{sup -1} in the Red Forest area located in the immediate vicinity of the Chernobyl Nuclear Power Plant site. Dose rate/effect relationships for morphological changes and cytogenetic defects were identified and correlations for radiation effects occurring on the morphological and cellular level were established.
Date: October 1, 2011
Creator: Farfan, E. & Jannik, T.
Object Type: Article
System: The UNT Digital Library
Clean Cities Guide to Alternative Fuel Commercial Lawn Equipment (Brochure) (open access)

Clean Cities Guide to Alternative Fuel Commercial Lawn Equipment (Brochure)

Guide explains the different types of alternative fuel commercial mowers and lists the makes and models of the ones available on the market. Turf grass is a fixture of the American landscape and the American economy. It is the nation's largest irrigated crop, covering more than 40 million acres. Legions of lawnmowers care for this expanse during the growing season-up to year-round in the warmest climates. The annual economic impact of the U.S. turf grass industry has been estimated at more than $62 billion. Lawn mowing also contributes to the nation's petroleum consumption and pollutant emissions. Mowers consume 1.2 billion gallons of gasoline annually, about 1% of U.S. motor gasoline consumption. Commercial mowing accounts for about 35% of this total and is the highest-intensity use. Large property owners and mowing companies cut lawns, sports fields, golf courses, parks, roadsides, and other grassy areas for 7 hours per day and consume 900 to 2,000 gallons of fuel annually depending on climate and length of the growing season. In addition to gasoline, commercial mowing consumes more than 100 million gallons of diesel annually. Alternative fuel mowers are one way to reduce the energy and environmental impacts of commercial lawn mowing. They can …
Date: October 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Collaborative Lubricating Oil Study on Emissions: November 28, 2006 - March 31, 2011 (open access)

Collaborative Lubricating Oil Study on Emissions: November 28, 2006 - March 31, 2011

The Collaborative Lubricating Oil Study on Emissions (CLOSE) project was a pilot investigation of how fuels and crankcase lubricants contribute to the formation of particulate matter (PM) and semi-volatile organic compounds (SVOC) in vehicle exhaust. As limited vehicles were tested, results are not representative of the whole on-road fleet. Long-term effects were not investigated. Pairs of vehicles (one normal PM emitting, one high-PM emitting) from four categories were selected: light-duty (LD) gasoline cars, medium-duty (MD) diesel trucks, heavy-duty (HD) natural-gas-fueled buses, and HD diesel buses. HD vehicles procured did not exhibit higher PM emissions, and thus were labeled high mileage (HM). Fuels evaluated were non-ethanol gasoline (E0), 10 percent ethanol (E10), conventional low-sulfur TxLED diesel, 20% biodiesel (B20), and natural gas. Temperature effects (20 degrees F, 72 degrees F) were evaluated on LD and MD vehicles. Lubricating oil vintage effects (fresh and aged) were evaluated on all vehicles. LD and MD vehicles were operated on a dynamometer over the California Unified Driving Cycle, while HD vehicles followed the Heavy Duty Urban Dynamometer Driving Schedule. Regulated and unregulated emissions were measured. Chemical markers from the unregulated emissions measurements and a tracer were utilized to estimate the lubricant contribution to PM.
Date: October 1, 2011
Creator: Carroll, J. N.; Khalek, I. A.; Smith, L. R.; Fujita, E. & Zielinska, B.
Object Type: Report
System: The UNT Digital Library
Comparative Study of Vented vs. Unvented Crawlspaces (open access)

Comparative Study of Vented vs. Unvented Crawlspaces

There has been a significant amount of research in the area of building energy efficiency and durability. However, well-documented quantitative information on the impact of crawlspaces on the performance of residential structures is lacking. The objective of this study was to evaluate and compare the effects of two crawlspace strategies on the whole-house performance of a pair of houses in a mixed humid climate. These houses were built with advanced envelope systems to provide energy savings of 50% or more compared to traditional 2010 new construction. One crawlspace contains insulated walls and is sealed and semi-conditioned. The other is a traditional vented crawlspace with insulation in the crawlspace ceiling. The vented (traditional) crawlspace contains fiberglass batts installed in the floor chase cavities above the crawl, while the sealed and insulated crawlspace contains foil-faced polyisocyanurate foam insulation on the interior side of the masonry walls. Various sensors to measure temperatures, heat flux through crawlspace walls and ceiling, and relative humidity were installed in the two crawlspaces. Data from these sensors have been analyzed to compare the performance of the two crawlspace designs. The analysis results indicated that the sealed and insulated crawlspace design is better than the traditional vented crawlspace in …
Date: October 1, 2011
Creator: Biswas, Kaushik; Christian, Jeffrey E & Gehl, Anthony C
Object Type: Report
System: The UNT Digital Library
Comparison of binary collision approximation and molecular dynamics for displacement cascades in GaAs. (open access)

Comparison of binary collision approximation and molecular dynamics for displacement cascades in GaAs.

The predictions of binary collision approximation (BCA) and molecular dynamics (MD) simulations of displacement cascades in GaAs are compared. There are three issues addressed in this work. The first is the optimal choice of the effective displacement threshold to use in the BCA calculations to obtain the best agreement with MD results. Second, the spatial correlations of point defects are compared. This is related to the level of clustering that occurs for different types of radiation. Finally, the size and structure of amorphous zones seen in the MD simulations is summarized. BCA simulations are not able to predict the formation of amorphous material.
Date: October 1, 2011
Creator: Foiles, Stephen Martin
Object Type: Report
System: The UNT Digital Library
Complex Adaptive System of Systems (CASoS) Engineering Applications. Version 1.0. (open access)

Complex Adaptive System of Systems (CASoS) Engineering Applications. Version 1.0.

Complex Adaptive Systems of Systems, or CASoS, are vastly complex eco-socio-economic-technical systems which we must understand to design a secure future for the nation and the world. Perturbations/disruptions in CASoS have the potential for far-reaching effects due to highly-saturated interdependencies and allied vulnerabilities to cascades in associated systems. The Phoenix initiative approaches this high-impact problem space as engineers, devising interventions (problem solutions) that influence CASoS to achieve specific aspirations. CASoS embody the world's biggest problems and greatest opportunities: applications to real world problems are the driving force of our effort. We are developing engineering theory and practice together to create a discipline that is grounded in reality, extends our understanding of how CASoS behave, and allows us to better control those behaviors. Through application to real-world problems, Phoenix is evolving CASoS Engineering principles while growing a community of practice and the CASoS engineers to populate it.
Date: October 1, 2011
Creator: Linebarger, John Michael; Maffitt, S. Louise (New Mexico Institute of Mining and Technology, Albuquerque, NM); Glass, Robert John, Jr.; Beyeler, Walter Eugene; Brown, Theresa Jean & Ames, Arlo Leroy
Object Type: Report
System: The UNT Digital Library
Component evaluation testing and analysis algorithms. (open access)

Component evaluation testing and analysis algorithms.

The Ground-Based Monitoring R&E Component Evaluation project performs testing on the hardware components that make up Seismic and Infrasound monitoring systems. The majority of the testing is focused on the Digital Waveform Recorder (DWR), Seismic Sensor, and Infrasound Sensor. In order to guarantee consistency, traceability, and visibility into the results of the testing process, it is necessary to document the test and analysis procedures that are in place. Other reports document the testing procedures that are in place (Kromer, 2007). This document serves to provide a comprehensive overview of the analysis and the algorithms that are applied to the Component Evaluation testing. A brief summary of each test is included to provide the context for the analysis that is to be performed.
Date: October 1, 2011
Creator: Hart, Darren M. & Merchant, Bion John
Object Type: Report
System: The UNT Digital Library
Concentrating Solar Power (Fact Sheet) (open access)

Concentrating Solar Power (Fact Sheet)

Concentrating Solar Power (CSP) offers a utility-scale, firm, dispatchable renewable energy option that can help meet the nation's goal of making solar energy cost competitive with other energy sources by the end of the decade. The DOE SunShot Initiative is a collaborative national initiative to make solar energy technologies cost-competitive with other forms of energy by reducing the cost of solar energy systems by about 75% by the end of the decade. Reducing the total installed cost for utility-scale solar electricity to roughly 6 cents per kilowatt hour without subsidies will result in rapid, large-scale adoption of solar electricity across the United States. Reaching this goal will re-establish American technological leadership, improve the nation's energy security, and strengthen U.S. economic competitiveness in the global clean energy race. SunShot will work to bring down the full cost of solar - including the costs of solar cells and installation by focusing on four main pillars: (1) Technologies for solar cells and arrays that convert sunlight to energy; (2) Electronics that optimize the performance of the installation; (3) Improvements in the efficiency of solar manufacturing processes; and (4) Installation, design, and permitting for solar energy systems.
Date: October 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Confined cooperative self-assembly and synthesis of optically and electrically active nanostructures : final LDRD report (open access)

Confined cooperative self-assembly and synthesis of optically and electrically active nanostructures : final LDRD report

In this project, we developed a confined cooperative self-assembly process to synthesize one-dimensional (1D) j-aggregates including nanowires and nanorods with controlled diameters and aspect ratios. The facile and versatile aqueous solution process assimilates photo-active macrocyclic building blocks inside surfactant micelles, forming stable single-crystalline high surface area nanoporous frameworks with well-defined external morphology defined by the building block packing. Characterizations using TEM, SEM, XRD, N{sub 2} and NO sorption isotherms, TGA, UV-vis spectroscopy, and fluorescence imaging and spectroscopy indicate that the j-aggregate nanostructures are monodisperse and may further assemble into hierarchical arrays with multi-modal functional pores. The nanostructures exhibit enhanced and collective optical properties over the individual chromophores. This project was a small footprint research effort which, nonetheless, produced significant progress towards both the stated goal as well as unanticipated research directions.
Date: October 1, 2011
Creator: Coker, Eric Nicholas; Haddad, Raid Edward (University of New Mexico, Albuquerque, NM); Fan, Hongyou; Ta, Anh (University of New Mexico, Albuquerque, NM); Bai, Feng (University of New Mexico, Albuquerque, NM); Rodriguez, Mark Andrew et al.
Object Type: Report
System: The UNT Digital Library
The Consortium for Advanced Simulation of Light Water Reactors (open access)

The Consortium for Advanced Simulation of Light Water Reactors

The Consortium for Advanced Simulation of Light Water Reactors (CASL) is a DOE Energy Innovation Hub for modeling and simulation of nuclear reactors. It brings together an exceptionally capable team from national labs, industry and academia that will apply existing modeling and simulation capabilities and develop advanced capabilities to create a usable environment for predictive simulation of light water reactors (LWRs). This environment, designated as the Virtual Environment for Reactor Applications (VERA), will incorporate science-based models, state-of-the-art numerical methods, modern computational science and engineering practices, and uncertainty quantification (UQ) and validation against data from operating pressurized water reactors (PWRs). It will couple state-of-the-art fuel performance, neutronics, thermal-hydraulics (T-H), and structural models with existing tools for systems and safety analysis and will be designed for implementation on both today's leadership-class computers and the advanced architecture platforms now under development by the DOE. CASL focuses on a set of challenge problems such as CRUD induced power shift and localized corrosion, grid-to-rod fretting fuel failures, pellet clad interaction, fuel assembly distortion, etc. that encompass the key phenomena limiting the performance of PWRs. It is expected that much of the capability developed will be applicable to other types of reactors. CASL's mission is to …
Date: October 1, 2011
Creator: Szilard, Ronaldo; Zhang, Hongbin; Kothe, Doug & Turinsky, Paul
Object Type: Article
System: The UNT Digital Library
CONTRIBUTING TO THE DISCUSSIONS ON THE FUNDAMENTAL ASPECTS AND COMPLEXITIES OF TALSPEAK CHEMISTRY (open access)

CONTRIBUTING TO THE DISCUSSIONS ON THE FUNDAMENTAL ASPECTS AND COMPLEXITIES OF TALSPEAK CHEMISTRY

When liquid-liquid distribution of lanthanides was monitored at Talspeak-related conditions a characteristic drop in the extraction efficiency was observed at high lactate concentrations. The lactate dependency trend also appears to be directly affected by the increasing complexity of the non-aqueous environment. Some considerations of the non-ideal solution behavior in aqueous and organic environment are presented here in an attempt to explain the observed metal partitioning trends. While the mechanism of metal ion phase transfer appears to adhere to the conventional thermodynamic struggle between HDEHP and DTPA, the diminished metal distribution and suppressed slopes for the extractant dependencies suggest further build-up in the complexity of the non-aqueous environment in Talspeak systems.
Date: October 1, 2011
Creator: Zalupski, Peter R. & Martin, Leigh R.
Object Type: Article
System: The UNT Digital Library
CRADA Final Report for CRADA Number ORNL00-0605: Advanced Engine/Aftertreatment System R&D (open access)

CRADA Final Report for CRADA Number ORNL00-0605: Advanced Engine/Aftertreatment System R&D

Navistar and ORNL established this CRADA to develop diesel engine aftertreatment configurations and control strategies that could meet emissions regulations while maintaining or improving vehicle efficiency. The early years of the project focused on reducing the fuel penalty associated with lean NOx trap (LNT), also known as NOx adsorber catalyst regeneration and desulfation. While Navistar pursued engine-based (in-cylinder) approaches to LNT regeneration, complementary experiments at ORNL focused on in-exhaust fuel injection. ORNL developed a PC-based controller for transient electronic control of EGR valve position, intake throttle position, and actuation of fuel injectors in the exhaust system of a Navistar engine installed at Oak Ridge. Aftertreatment systems consisting of different diesel oxidation catalysts (DOCs) in conjunction with a diesel particle filter and LNT were evaluated under quasi-steady-state conditions. Hydrocarbon (HC) species were measured at multiple locations in the exhaust system with Gas chromatograph mass spectrometry (GC-MS) and Fourier transform infrared (FTIR) spectroscopy. Under full-load, rated speed conditions, injection of fuel upstream of the DOC reduced the fuel penalty for a given level of NOx reduction by 10-20%. GC-MS showed that fuel compounds were 'cracked' into smaller hydrocarbon species over the DOC, particularly light alkenes. GC-MS analysis of HC species entering and …
Date: October 1, 2011
Creator: Pihl, Josh A; West, Brian H; Toops, Todd J; Adelman, Brad & Derybowski, Edward
Object Type: Report
System: The UNT Digital Library
Deep Vadose Zone-Applied Field Research Initiative Fiscal Year 2011 Annual Report (open access)

Deep Vadose Zone-Applied Field Research Initiative Fiscal Year 2011 Annual Report

This annual report describes the background of the Deep Vadose Zone-Applied Field Research Initiative, and some of the programmatic approaches and transformational technologies in groundwater and deep vadose zone remediation developed during fiscal year 2011. The Department of Energy (DOE) Office of Technology Innovation and Development's (OTID) mission is to transform science into viable solutions for environmental cleanup. In 2010, OTID developed the Impact Plan, Science and Technology to Reduce the Life Cycle Cost of Closure to outline the benefits of research and development of the lifecycle cost of cleanup across the DOE complex. This plan outlines OTID's ability to reduce by $50 billion, the $200 billion life-cycle cost in waste processing, groundwater and soil, nuclear materials, and deactivation and decommissioning. The projected life-cycle costs and return on investment are based on actual savings realized from technology innovation, development, and insertion into remedial strategies and schedules at the Fernald, Mound, and Ashtabula sites. To achieve our goals, OTID developed Applied Field Research Initiatives to facilitate and accelerate collaborative development and implementation of new tools and approaches that reduce risk, cost and time for site closure. The primary mission of the Deep Vadose Zone-Applied Field Research Initiative (DVZ-AFRI) is to protect …
Date: October 1, 2011
Creator: Wellman, Dawn M.; Johnson, Timothy C.; Smith, Ronald M.; Truex, Michael J. & Matthews, Hope E.
Object Type: Report
System: The UNT Digital Library
Density Functional Theory Simulations Predict New Materials for Magnesium-Ion Batteries (Fact Sheet), NREL Highlights, Science (open access)

Density Functional Theory Simulations Predict New Materials for Magnesium-Ion Batteries (Fact Sheet), NREL Highlights, Science

Multivalence is identified in the light element, B, through structure morphology. Boron sheets exhibit highly versatile valence, and the layered boron materials may hold the promise of a high-energy-density magnesium-ion battery. Practically, boron is superior to previously known multivalence materials, especially transition metal compounds, which are heavy, expensive, and often not benign. Based on density functional theory simulations, researchers at the National Renewable Energy Laboratory (NREL) have predicted a series of stable magnesium borides, MgB{sub x}, with a broad range of stoichiometries, 2 < x < 16, by removing magnesium atoms from MgB{sub 2}. The layered boron structures are preserved through an in-plane topological transformation between the hexagonal lattice domains and the triangular domains. The process can be reversibly switched as the charge transfer changes with Mg insertion/extraction. The mechanism of such a charge-driven transformation originates from the versatile valence state of boron in its planar form. The discovery of these new physical phenomena suggests the design of a high-capacity magnesium-boron battery with theoretical energy density 876 mAh/g and 1550 Wh/L.
Date: October 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Denver, Colorado: Solar in Action (Brochure) (open access)

Denver, Colorado: Solar in Action (Brochure)

This brochure provides an overview of the challenges and successes of Denver, Colorado, a 2008 Solar America City awardee, on the path toward becoming a solar-powered community. Accomplishments, case studies, key lessons learned, and local resource information are given.
Date: October 1, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library