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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
State of the Art in Floating Wind Turbine Design Tools (open access)

State of the Art in Floating Wind Turbine Design Tools

This paper presents an overview of the simulation codes available to the offshore wind industry that are capable of performing integrated dynamic calculations for floating offshore wind turbines.
Date: October 1, 2011
Creator: Cordle, A. & Jonkman, J.
Object Type: Article
System: The UNT Digital Library

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
Solar Schools Assessment and Implementation Project: Financing Options for Solar Installations on K-12 Schools (open access)

Solar Schools Assessment and Implementation Project: Financing Options for Solar Installations on K-12 Schools

This report focuses on financial options developed specifically for renewable energy and energy efficiency projects in three California public school districts. Solar energy systems installed on public schools have a number of benefits that include utility bill savings, reductions in greenhouse gas emissions (GHGs) and other toxic air contaminants, job creation, demonstrating environmental leadership, and creating learning opportunities for students. In the 2011 economic environment, the ability to generate general-fund savings as a result of reducing utility bills has become a primary motivator for school districts trying to cut costs. To achieve meaningful savings, the size of the photovoltaic (PV) systems installed (both individually on any one school and collectively across a district) becomes much more important; larger systems are required to have a material impact on savings. Larger PV systems require a significant financial commitment and financing therefore becomes a critical element in the transaction. In simple terms, school districts can use two primary types of ownership models to obtain solar installations and cost savings across a school district. The PV installations can be financed and owned directly by the districts themselves. Alternatively, there are financing structures whereby another entity, such as a solar developer or its investors, actually …
Date: October 1, 2011
Creator: Coughlin, J. & Kandt, A.
Object Type: Report
System: The UNT Digital Library
Nanomanufacturing : nano-structured materials made layer-by-layer. (open access)

Nanomanufacturing : nano-structured materials made layer-by-layer.

Large-scale, high-throughput production of nano-structured materials (i.e. nanomanufacturing) is a strategic area in manufacturing, with markets projected to exceed $1T by 2015. Nanomanufacturing is still in its infancy; process/product developments are costly and only touch on potential opportunities enabled by growing nanoscience discoveries. The greatest promise for high-volume manufacturing lies in age-old coating and imprinting operations. For materials with tailored nm-scale structure, imprinting/embossing must be achieved at high speeds (roll-to-roll) and/or over large areas (batch operation) with feature sizes less than 100 nm. Dispersion coatings with nanoparticles can also tailor structure through self- or directed-assembly. Layering films structured with these processes have tremendous potential for efficient manufacturing of microelectronics, photovoltaics and other topical nano-structured devices. This project is designed to perform the requisite R and D to bring Sandia's technology base in computational mechanics to bear on this scale-up problem. Project focus is enforced by addressing a promising imprinting process currently being commercialized.
Date: October 1, 2011
Creator: Cox, James V.; Cheng, Shengfeng; Grest, Gary Stephen; Tjiptowidjojo, Kristianto (University of New Mexico); Reedy, Earl David, Jr.; Fan, Hongyou et al.
Object Type: Report
System: The UNT Digital Library
The Upgrade Path from Legacy VME to VXS Dual Star Connectivity for Large Scale Data Acquisition and Trigger Systems (open access)

The Upgrade Path from Legacy VME to VXS Dual Star Connectivity for Large Scale Data Acquisition and Trigger Systems

New instrumentation modules have been designed by Jefferson Lab and to take advantage of the higher performance and elegant backplane connectivity of the VITA 41 VXS standard. These new modules are required to meet the 200KHz trigger rates envisioned for the 12GeV experimental program. Upgrading legacy VME designs to the high speed gigabit serial extensions that VXS offers, comes with significant challenges, including electronic engineering design, plus firmware and software development issues. This paper will detail our system design approach including the critical system requirement stages, and explain the pipeline design techniques and selection criteria for the FPGA that require embedded Gigabit serial transceivers. The entire trigger system is synchronous and operates at 250MHz clock with synchronization signals, and the global trigger signals distributed to each front end readout crate via the second switch slot in the 21 slot, dual star VXS backplane. The readout of the buffered detector signals relies on 2eSST over the standard VME64x path at >200MB/s. We have achieved 20Gb/s transfer rate of trigger information within one VXS crate and will present results using production modules in a two crate test configuration with both VXS crates fully populated. The VXS trigger modules that reside in the …
Date: October 1, 2011
Creator: Cuevas, C; Barbosa, F J; Dong, H; Gu, W; Jastrzembski, E; Kaneta, S R et al.
Object Type: Article
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
Beam lifetime and emittance growth in RHIC under normal operating conditions with the hydrogen gas jet, the cluster-jet, and Pellet targets (open access)

Beam lifetime and emittance growth in RHIC under normal operating conditions with the hydrogen gas jet, the cluster-jet, and Pellet targets

N/A
Date: October 1, 2011
Creator: D., Trbojevic
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Saturday, October 1, 2011 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Saturday, October 1, 2011

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: October 1, 2011
Creator: DeSilver, Debi
Object Type: Newspaper
System: The Gateway to Oklahoma History
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
Integration of High Temperature Gas-cooled Reactor Technology with Oil Sands Processes (open access)

Integration of High Temperature Gas-cooled Reactor Technology with Oil Sands Processes

This paper summarizes an evaluation of siting an HTGR plant in a remote area supplying steam, electricity and high temperature gas for recovery and upgrading of unconventional crude oil from oil sands. The area selected for this evaluation is the Alberta Canada oil sands. This is a very fertile and active area for bitumen recovery and upgrading with significant quantities piped to refineries in Canada and the U.S Additionally data on the energy consumption and other factors that are required to complete the evaluation of HTGR application is readily available in the public domain. There is also interest by the Alberta oil sands producers (OSP) in identifying alternative energy sources for their operations. It should be noted, however, that the results of this evaluation could be applied to any similar oil sands area.
Date: October 1, 2011
Creator: Demick, L. E.
Object Type: Report
System: The UNT Digital Library
Next Generation Nuclear Plant Project Evaluation of Siting a HTGR Co-generation Plant on an Operating Commercial Nuclear Power Plant Site (open access)

Next Generation Nuclear Plant Project Evaluation of Siting a HTGR Co-generation Plant on an Operating Commercial Nuclear Power Plant Site

This paper summarizes an evaluation by the Idaho National Laboratory (INL) Next Generation Nuclear Plant (NGNP) Project of siting a High Temperature Gas-cooled Reactor (HTGR) plant on an existing nuclear plant site that is located in an area of significant industrial activity. This is a co-generation application in which the HTGR Plant will be supplying steam and electricity to one or more of the nearby industrial plants.
Date: October 1, 2011
Creator: Demick, L. E.
Object Type: Report
System: The UNT Digital Library
Next Generation Nuclear Plant Project Evaluation of Siting a HTGR Co-generation Plant on an Operating Commercial Nuclear Power Plant Site (open access)

Next Generation Nuclear Plant Project Evaluation of Siting a HTGR Co-generation Plant on an Operating Commercial Nuclear Power Plant Site

This paper summarizes an evaluation by the Idaho National Laboratory (INL) Next Generation Nuclear Plant (NGNP) Project of siting a High Temperature Gas-cooled Reactor (HTGR) plant on an existing nuclear plant site that is located in an area of significant industrial activity. This is a co-generation application in which the HTGR Plant will be supplying steam and electricity to one or more of the nearby industrial plants.
Date: October 1, 2011
Creator: Demick, L. E.
Object Type: Report
System: The UNT Digital Library
Iraq liquid radioactive waste tanks maintenance and monitoring program plan. (open access)

Iraq liquid radioactive waste tanks maintenance and monitoring program plan.

The purpose of this report is to develop a project management plan for maintaining and monitoring liquid radioactive waste tanks at Iraq's Al-Tuwaitha Nuclear Research Center. Based on information from several sources, the Al-Tuwaitha site has approximately 30 waste tanks that contain varying amounts of liquid or sludge radioactive waste. All of the tanks have been non-operational for over 20 years and most have limited characterization. The program plan embodied in this document provides guidance on conducting radiological surveys, posting radiation control areas and controlling access, performing tank hazard assessments to remove debris and gain access, and conducting routine tank inspections. This program plan provides general advice on how to sample and characterize tank contents, and how to prioritize tanks for soil sampling and borehole monitoring.
Date: October 1, 2011
Creator: Dennis, Matthew L.; Cochran, John Russell & Sol Shamsaldin, Emad (Iraq Ministry of Science and Technology)
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
Neutral Current Elastic Interactions in MiniBooNE (open access)

Neutral Current Elastic Interactions in MiniBooNE

Neutral Current Elastic (NCE) interactions in MiniBooNE are discussed. In the neutrino mode MiniBooNE reported: the flux averaged NCE differential cross section as a function of four-momentum transferred squared, an axial mass (M{sub A}) measurement, and a measurement of the strange quark spin content of the nucleon, {Delta}s. In the antineutrino mode we present the background-subtracted data which is compared with the Monte Carlo predictions.
Date: October 1, 2011
Creator: Dharmapalan, Ranjan
Object Type: Article
System: The UNT Digital Library
Neutrino and Antineutrino Cross sections at MiniBooNE (open access)

Neutrino and Antineutrino Cross sections at MiniBooNE

The MiniBooNE experiment has reported a number of high statistics neutrino and anti-neutrino cross sections -among which are the charged current quasi-elastic (CCQE) and neutral current elastic (NCE) neutrino scattering on mineral oil (CH2). Recently a study of the neutrino contamination of the anti-neutrino beam has concluded and the analysis of the anti-neutrino CCQE and NCE scattering is ongoing.
Date: October 1, 2011
Creator: Dharmapalan, Ranjan
Object Type: Article
System: The UNT Digital Library
Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2010 (open access)

Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2010

This report describes the 2010 research conducted under the U.S. Army Corps of Engineers (USACE) project EST-P-09-1, titled Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, and known as the 'Salmon Benefits' study. The primary goal of the study is to establish scientific methods to quantify habitat restoration benefits to listed salmon and trout in the lower Columbia River and estuary (LCRE) in three required areas: habitat connectivity, early life history diversity, and survival (Figure ES.1). The general study approach was to first evaluate the state of the science regarding the ability to quantify benefits to listed salmon and trout from habitat restoration actions in the LCRE in the 2009 project year, and then, if feasible, in subsequent project years to develop quantitative indices of habitat connectivity, early life history diversity, and survival. Based on the 2009 literature review, the following definitions are used in this study. Habitat connectivity is defined as a landscape descriptor concerning the ability of organisms to move among habitat patches, including the spatial arrangement of habitats (structural connectivity) and how the perception and behavior of salmon affect the potential for movement …
Date: October 1, 2011
Creator: Diefenderfer, Heida L.; Johnson, Gary E.; Sather, Nichole K.; Skalski, J. R.; Dawley, Earl M.; Coleman, Andre M. et al.
Object Type: Report
System: The UNT Digital Library
Pyrometry simulator (pyrosim) for diagnostic design. (open access)

Pyrometry simulator (pyrosim) for diagnostic design.

Signal estimates are crucial to the design of time-resolved pyrometry measurements. These estimates affect fundamental design decisions, including the optical relay (fiber versus open beam), spectral range (visible or infrared), and amplification needs (possibly at the expense of time resolution). The pyrosim program makes such estimates, allowing the collected power, photon flux, and measured signal to be determined in a broad range of pyrometry measurements. Geometrical collection limits can be applied; sample emissivity, transfer efficiency, and detector sensitivity may also be specified, either as constants or functions of wavelength.
Date: October 1, 2011
Creator: Dolan, Daniel H., III
Object Type: Report
System: The UNT Digital Library
Impact of Different Economic Performance Metrics on the Perceived Value of Solar Photovoltaics (open access)

Impact of Different Economic Performance Metrics on the Perceived Value of Solar Photovoltaics

Photovoltaic (PV) systems are installed by several types of market participants, ranging from residential customers to large-scale project developers and utilities. Each type of market participant frequently uses a different economic performance metric to characterize PV value because they are looking for different types of returns from a PV investment. This report finds that different economic performance metrics frequently show different price thresholds for when a PV investment becomes profitable or attractive. Several project parameters, such as financing terms, can have a significant impact on some metrics [e.g., internal rate of return (IRR), net present value (NPV), and benefit-to-cost (B/C) ratio] while having a minimal impact on other metrics (e.g., simple payback time). As such, the choice of economic performance metric by different customer types can significantly shape each customer's perception of PV investment value and ultimately their adoption decision.
Date: October 1, 2011
Creator: Drury, E.; Denholm, P. & Margolis, R.
Object Type: Report
System: The UNT Digital Library
The lightest hybrid meson supermultiplet in QCD (open access)

The lightest hybrid meson supermultiplet in QCD

We interpret the spectrum of meson states recently obtained in non-perturbative lattice QCD calculations in terms of constituent quark-antiquark bound states and states, called 'hybrids', in which the q{bar q} pair is supplemented by an excitation of the gluonic field. We identify a lightest supermultiplet of hybrid mesons with J{sup PC} = (0,1,2){sup {-+}}, 1{sup -} built from a gluonic excitation of chromomagnetic character coupled to q{bar q} in an S-wave. The next lightest hybrids are suggested to be quark orbital excitations with the same gluonic excitation, while the next distinct gluonic excitation is significantly heavier. Existing models of gluonic excitations are compared to these findings and possible phenomenological consequences explored.
Date: October 1, 2011
Creator: Dudek, Jozef J.
Object Type: Article
System: The UNT Digital Library
LIDAR Wind Speed Measurement Analysis and Feed-Forward Blade Pitch Control for Load Mitigation in Wind Turbines: January 2010--January 2011 (open access)

LIDAR Wind Speed Measurement Analysis and Feed-Forward Blade Pitch Control for Load Mitigation in Wind Turbines: January 2010--January 2011

This report examines the accuracy of measurements that rely on Doppler LIDAR systems to determine their applicability to wind turbine feed-forward control systems and discusses feed-forward control system designs that use preview wind measurements. Light Detection and Ranging (LIDAR) systems are able to measure the speed of incoming wind before it interacts with a wind turbine rotor. These preview wind measurements can be used in feed-forward control systems designed to reduce turbine loads. However, the degree to which such preview-based control techniques can reduce loads by reacting to turbulence depends on how accurately the incoming wind field can be measured. The first half of this report examines the accuracy of different measurement scenarios that rely on coherent continuous-wave or pulsed Doppler LIDAR systems to determine their applicability to feed-forward control. In particular, the impacts of measurement range and angular offset from the wind direction are studied for various wind conditions. A realistic case involving a scanning LIDAR unit mounted in the spinner of a wind turbine is studied in depth with emphasis on choices for scan radius and preview distance. The effects of turbulence parameters on measurement accuracy are studied as well. Continuous-wave and pulsed LIDAR models based on typical …
Date: October 1, 2011
Creator: Dunne, F.; Simley, E. & Pao, L.Y.
Object Type: Report
System: The UNT Digital Library
Fully integrated safeguards and security for reprocessing plant monitoring. (open access)

Fully integrated safeguards and security for reprocessing plant monitoring.

Nuclear fuel reprocessing plants contain a wealth of plant monitoring data including material measurements, process monitoring, administrative procedures, and physical protection elements. Future facilities are moving in the direction of highly-integrated plant monitoring systems that make efficient use of the plant data to improve monitoring and reduce costs. The Separations and Safeguards Performance Model (SSPM) is an analysis tool that is used for modeling advanced monitoring systems and to determine system response under diversion scenarios. This report both describes the architecture for such a future monitoring system and present results under various diversion scenarios. Improvements made in the past year include the development of statistical tests for detecting material loss, the integration of material balance alarms to improve physical protection, and the integration of administrative procedures. The SSPM has been used to demonstrate how advanced instrumentation (as developed in the Material Protection, Accounting, and Control Technologies campaign) can benefit the overall safeguards system as well as how all instrumentation is tied into the physical protection system. This concept has the potential to greatly improve the probability of detection for both abrupt and protracted diversion of nuclear material.
Date: October 1, 2011
Creator: Duran, Felicia Angelica; Ward, Rebecca; Cipiti, Benjamin B. & Middleton, Bobby D.
Object Type: Report
System: The UNT Digital Library
Wide Area Thermal Processing of Light Emitting Materials (open access)

Wide Area Thermal Processing of Light Emitting Materials

Laboratory laser materials synthesis of wide bandgap materials has been successfully used to create white light emitting materials (LEMs). This technology development has progressed to the exploration on design and construction of apparatus for wide area doping and phase transformation of wide bandgap material substrates. The objective of this proposal is to develop concepts for wide area doping and phase transformation based on AppliCote Associates, LLC laser technology and ORNL high density pulsed plasma arc technology.
Date: October 1, 2011
Creator: Duty, Chad E; Joshi, Pooran C; Jellison Jr, Gerald Earle; Angelini, Joseph Attilio & Sabau, Adrian S
Object Type: Report
System: The UNT Digital Library