States

Design and Development of Selective Extractants for An/Ln Separations (open access)

Design and Development of Selective Extractants for An/Ln Separations

This study has succeeded in further developing phosphinoylmethyl pyridine compounds as selective recognition and separations agents for trivalent lanthanide and actinide ions present in nuclear materials. The parameters for efficient separations have been further elucidated and factors important to further development have been identified. Further development will lead to optimal extractant design for effective actinide ion partitioning under process practical conditions. The primary objective of the project involved the design, synthesis, and characterization of the extraction performance of 2,6-bis(phosphinomethyl)pyridine N,P,P{prime}-trioxides (NOPOPO) as potential reagents for the separation of Am, Cm, and fission product lanthanides from other transuranics and fission products and for acting as a separations 'platform' for the mutual separation of Am/Cm from the lanthanides. The secondary but critical objective of the project focused on the characterization of aqueous acid and radiation stability of NOPOPO ligands. Further, the project served as a interdisciplinary training vehicle for new, young investigators in actinide separations chemistry.
Date: December 4, 2009
Creator: Paine, Robert T.
Object Type: Report
System: The UNT Digital Library
Durable Glass for Thousands of Years (open access)

Durable Glass for Thousands of Years

The durability of natural glasses on geological time scales and ancient glasses for thousands of years is well documented. The necessity to predict the durability of high level nuclear waste (HLW) glasses on extended time scales has led to various thermodynamic and kinetic approaches. Advances in the measurement of medium range order (MRO) in glasses has led to the understanding that the molecular structure of a glass, and thus the glass composition, controls the glass durability by establishing the distribution of ion exchange sites, hydrolysis sites, and the access of water to those sites. During the early stages of glass dissolution, a 'gel' layer resembling a membrane forms through which ions exchange between the glass and the leachant. The hydrated gel layer exhibits acid/base properties which are manifested as the pH dependence of the thickness and nature of the gel layer. The gel layer ages into clay or zeolite minerals by Ostwald ripening. Zeolite mineral assemblages (higher pH and Al{sup 3+} rich glasses) may cause the dissolution rate to increase which is undesirable for long-term performance of glass in the environment. Thermodynamic and structural approaches to the prediction of glass durability are compared versus Ostwald ripening.
Date: December 4, 2009
Creator: Jantzen, Carol M.; Brown, Kevin G. & Pickett, J. B.
Object Type: Article
System: The UNT Digital Library
An Experimental and Kinetic Modeling Study of Methyl Decanoate Combustion (open access)

An Experimental and Kinetic Modeling Study of Methyl Decanoate Combustion

Biodiesel is a mixture of long chain fatty acid methyl esters derived from fats and oils. This research study presents opposed-flow diffusion flame data for one large fatty acid methyl ester, methyl decanoate, and uses the experiments to validate an improved skeletal mechanism consisting of 648 species and 2998 reactions. The results indicate that methyl decanoate is consumed via abstraction of hydrogen atoms to produce fuel radicals, which lead to the production of alkenes. The ester moiety in methyl decanoate leads to the formation of low molecular weight oxygenated compounds such as carbon monoxide, formaldehyde, and ketene.
Date: December 4, 2009
Creator: Sarathy, S M; Thomson, M J; Pitz, W J & Lu, T
Object Type: Article
System: The UNT Digital Library

Material Needs for Thin-Film and Concentrator Photovoltaic Modules

This presentation describes the ongoing needs (manufacturability, availability, low cost, performance, and reliability) that drive the development of new photovoltaic materials.
Date: December 4, 2009
Creator: Kurtz, S.
Object Type: Presentation
System: The UNT Digital Library
Metal Angle Correction in the Cylinder Test (open access)

Metal Angle Correction in the Cylinder Test

None
Date: December 4, 2009
Creator: Souers, P. C.; Garza, R.; Hornig, H.; Lauderbach, L.; Owens, C. & Vitello, P.
Object Type: Article
System: The UNT Digital Library
NANOSTRUCTURED METAL OXIDES FOR ANODES OF LI-ION RECHARGEABLE BATTERIES (open access)

NANOSTRUCTURED METAL OXIDES FOR ANODES OF LI-ION RECHARGEABLE BATTERIES

The aligned nanorods of Co{sub 3}O{sub 4} and nanoporous hollow spheres (NHS) of SnO{sub 2} and Mn{sub 2}O{sub 3} were investigated as the anodes for Li-ion rechargeable batteries. The Co{sub 3}O{sub 4} nanorods demonstrated 1433 mAh/g reversible capacity. The NHS of SnO{sub 2} and Mn{sub 2}O{sub 3} delivered 400 mAh/g and 250 mAh/g capacities respectively in multiple galvonastatic discharge-charge cycles. It was found that high capacity of NHS of metal oxides is sustainable attributed to their unique structure that maintains material integrity during cycling. The nanostructured metal oxides exhibit great potential as the new anode materials for Li-ion rechargeable batteries with high energy density, low cost and inherent safety.
Date: December 4, 2009
Creator: Au, M.
Object Type: Article
System: The UNT Digital Library
Nuclear quantum effects in the structure and lineshapes of the N2 NEXAFS spectrum (open access)

Nuclear quantum effects in the structure and lineshapes of the N2 NEXAFS spectrum

We study the relative ability of several models of the X-ray absorption spectrum to capture the Franck-Condon structure apparent from an experiment on gaseous nitrogen. In doing so, we adopt the Born-Oppenheimer approximation and a constrained density functional theory method for computing the energies of the X-ray-excited molecule. Starting from an otherwise classical model for the spectrum, we systematically introduce more realistic physics, first by substituting the quantum mechanical nuclear radial density in the bond separation R for the classical radial density, then by adding the effect of zero-point energy and other level shifts, and finally by including explicit rovibrational quantization of both the ground and excited states. The quantization is determined exactly, using a discrete variable representation. We show that the NEXAFS spectrum can be predicted semiquantiatively within this framework. We also address the possibility of non-trivial temperature dependence in the spectrum. Finally, we show that it is possible to improve the predicted spectrum by using constrained DFT in combination with more accurate potentials.
Date: December 4, 2009
Creator: Fatehi, Shervin; Schwartz, Craig P.; Saykally, Richard J. & Prendergast, David
Object Type: Article
System: The UNT Digital Library
PEP Run Report for Integrated Test A, Caustic Leaching in UFP-VSL-T01A, Oxidative Leaching in UFP-VSL-T02A (open access)

PEP Run Report for Integrated Test A, Caustic Leaching in UFP-VSL-T01A, Oxidative Leaching in UFP-VSL-T02A

Pacific Northwest National Laboratory (PNNL) was tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed and constructed and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes.”(a) The PEP, located in the Process Engineering Laboratory-West (PDLW) located in Richland, Washington, is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing.
Date: December 4, 2009
Creator: Guzman-Leong, Consuelo E.; Bredt, Ofelia P.; Burns, Carolyn A.; Daniel, Richard C.; Su, Yin-Fong; Geeting, John GH et al.
Object Type: Report
System: The UNT Digital Library
Proceedings of the 25th Rare Earth Research Conference, June 22-26, Tuscaloosa, Alabama, USA Journal of Alloys and Compounds 2009, Vol. 488, Iss. 2, pp 491-656 (open access)

Proceedings of the 25th Rare Earth Research Conference, June 22-26, Tuscaloosa, Alabama, USA Journal of Alloys and Compounds 2009, Vol. 488, Iss. 2, pp 491-656

The program of the 25th Rare Earth Research Conference (RERC08) integrated basic and applied multidisciplinary research centered on the f-elements. Leading science was featured in the form of invited oral presentations and contributed posters on topics in f-element chemistry, physics, and material, earth, environmental, and biological sciences. The conference was held in Shelby Hall, located on The University of Alabama?s Tuscaloosa, AL campus. The final program and list of attendees is available at URL http://bama.ua.edu/~rdrogers/RERC08/.
Date: December 4, 2009
Creator: Rogers, Robin D.
Object Type: Article
System: The UNT Digital Library
quantifying and Predicting Reactive Transport (open access)

quantifying and Predicting Reactive Transport

This project was led by Dr. Jiamin Wan at Lawrence Berkeley National Laboratory. Peter Burns provided expertise in uranium mineralogy and in identification of uranium minerals in test materials. Dr. Wan conducted column tests regarding uranium transport at LBNL, and samples of the resulting columns were sent to Dr. Burns for analysis. Samples were analyzed for uranium mineralogy by X-ray powder diffraction and by scanning electron microscopy, and results were provided to Dr. Wan for inclusion in the modeling effort. Full details of the project can be found in Dr. Wan's final reports for the associated effort at LBNL.
Date: December 4, 2009
Creator: Burns, Peter C.
Object Type: Report
System: The UNT Digital Library
Scientific/Technical Report Bioenergetics Research Initiative Award number-DE-FG02-05ER64092 (open access)

Scientific/Technical Report Bioenergetics Research Initiative Award number-DE-FG02-05ER64092

General Project Overview and Final Technical Report This equipment grant was utilized to enhance the infrastructure of the Human Performance Laboratory at Ball State University. The laboratories primary focus is human based exercise physiology conducting research in the areas of sports performance, aging and exercise, unloading (space flight and bed rest), pediatric exercise and clinical exercise physiology. The main equipment supported by this grant was an ultrasound unit for cardiac and skeletal muscle imaging at the whole organ level, microscope system for micro imaging of skeletal muscle tissue, running treadmill for energy expenditure assessment, autoclave for sterilization, and upgrade to our dual x‐ray absorptiometry (DEXA) system that was utilized for body composition measurements. The equipment was involved in several human metabolic and skeletal muscle research projects as highlighted above. In particular, this equipment served a support role for other large‐scale clinical projects funded by the National Institutes of Health (NIH), National Aeronautics and Space Administration (NASA), and corporate sponsors.
Date: December 4, 2009
Creator: Trappe, Scott A.
Object Type: Report
System: The UNT Digital Library
Studies of SmCo5/Fe nanocomposite magnetic bilayers with magnetic soft x-ray transmission microscopy (open access)

Studies of SmCo5/Fe nanocomposite magnetic bilayers with magnetic soft x-ray transmission microscopy

A hard/soft SmCo{sub 5}/Fe nanocomposite magnetic bilayer system has been fabricated on X-ray transparent 100-200 nm thin Si{sub 3}N{sub 4} membranes by magnetron sputtering. The microscopic magnetic domain pattern and its behavior during magnetization reversal in the hard and soft magnetic phases have been individually studied by element specific magnetic soft x-ray microscopy at a spatial resolution of better than 25nm. We observe that the domain patterns for soft and hard phases switch coherently throughout the full hysteresis cycle upon applying external magnetic fields. We derived local M(H) curves from the images for Fe and SmCo5 separately and found switching for both hard and soft phases same.
Date: December 4, 2009
Creator: Shahzad, F.; Siddiqi, S. A.; Im, M.-Y.; Avallone, A.; Fischer, P.; Hussain, Z. et al.
Object Type: Article
System: The UNT Digital Library
TMTI Task 1.6 Genetic Engineering Methods and Detection (open access)

TMTI Task 1.6 Genetic Engineering Methods and Detection

A large number of GE techniques can be adapted from other microorganisms to biothreat bacteria and viruses. Detection of GE in a microorganism increases in difficulty as the size of the genetic change decreases. In addition to the size of the engineered change, the consensus genomic sequence of the microorganism can impact the difficulty of detecting an engineered change in genomes that are highly variable from strain to strain. This problem will require comprehensive databases of whole genome sequences for more genetically variable biothreat bacteria and viruses. Preliminary work with microarrays for detecting synthetic elements or virulence genes and analytic bioinformatic approaches for whole genome sequence comparison to detect genetic engineering show promise for attacking this difficult problem but a large amount of future work remains.
Date: December 4, 2009
Creator: Slezak, T.; Lenhoff, R.; Allen, J.; Borucki, M.; Vitalis, E. & Gardner, S.
Object Type: Report
System: The UNT Digital Library

22nd NREL Industry Growth Forum Opening Remarks - Day 2

A presentation at the 22nd Industry Growth Forum by Tod Perry that provides information and statistics about the presenting companies.
Date: November 4, 2009
Creator: Perry, T.
Object Type: Presentation
System: The UNT Digital Library
Functional Evaluation of the DOZA DKG-05D Electronic Dosimeter System (open access)

Functional Evaluation of the DOZA DKG-05D Electronic Dosimeter System

The DOZA DKG-05D electronic personal dosimeter (EPD) was the subject of a limited type-test evaluation in support of Plutonium Production Reactor Agreement (PPRA) Implementation. The primary goal of this evaluation was to provide confidence in the functionality of the dosimeter and identify potential weaknesses in PPRA applications. The tests were based on IEC-61526, recommendations of the International Electrotechnical Commission pertaining to EPDs. All tests were performed in Pacific Northwest National Laboratory’s (PNNL) Radiological Calibrations and Standards Facility in the 318 building. The first testing category was functional considerations. The tests found that the mechanical characteristics of the DKG-05D support usability. However, user controls are not intuitive and straightforward, and the user instructions were unclear and difficult to follow. The unit functioned in a variety of humidity conditions. In high temperature conditions it performed well. However, in cold conditions the display began to fade, which limits its usefulness below about 5 °C. The vendor claims that the unit functions to -20 °C, and it may be correctly recording doses at that low temperature, but the doses cannot be read in real time. Testing found that battery life is generally good, operating for 200 hours on a full charge. This is far …
Date: November 4, 2009
Creator: Piper, Roman K. & Scherpelz, Robert I.
Object Type: Report
System: The UNT Digital Library
Ground motion modeling of Hayward fault scenario earthquakes II:Simulation of long-period and broadband ground motions (open access)

Ground motion modeling of Hayward fault scenario earthquakes II:Simulation of long-period and broadband ground motions

We simulate long-period (T > 1.0-2.0 s) and broadband (T > 0.1 s) ground motions for 39 scenarios earthquakes (Mw 6.7-7.2) involving the Hayward, Calaveras, and Rodgers Creek faults. For rupture on the Hayward fault we consider the effects of creep on coseismic slip using two different approaches, both of which reduce the ground motions compared with neglecting the influence of creep. Nevertheless, the scenario earthquakes generate strong shaking throughout the San Francisco Bay area with about 50% of the urban area experiencing MMI VII or greater for the magnitude 7.0 scenario events. Long-period simulations of the 2007 Mw 4.18 Oakland and 2007 Mw 4.5 Alum Rock earthquakes show that the USGS Bay Area Velocity Model version 08.3.0 permits simulation of the amplitude and duration of shaking throughout the San Francisco Bay area, with the greatest accuracy in the Santa Clara Valley (San Jose area). The ground motions exhibit a strong sensitivity to the rupture length (or magnitude), hypocenter (or rupture directivity), and slip distribution. The ground motions display a much weaker sensitivity to the rise time and rupture speed. Peak velocities, peak accelerations, and spectral accelerations from the synthetic broadband ground motions are, on average, slightly higher than the …
Date: November 4, 2009
Creator: Aagaard, B T; Graves, R W; Rodgers, A; Brocher, T M; Simpson, R W; Dreger, D et al.
Object Type: Article
System: The UNT Digital Library
Standard Measurement & Verification Plan for Lighting Equipment Retrofit or Replacement Projects (open access)

Standard Measurement & Verification Plan for Lighting Equipment Retrofit or Replacement Projects

This document provides a framework for a standard Measurement and Verification (M&V) plan for lighting projects. It was developed to support cost-effective retrofits (partial and complete replacements) of lighting systems and is intended to provide a foundation for an M&V plan for a lighting retrofit utilizing a "best practice" approach, and to provide guidance to site owners, contractors, and other involved organizations on what is essential for a robust M&V plan for lighting projects. This document provides examples of appropriate elements of an M&V plan, including the calculation of expected energy savings. The standard M&V plan, as provided, also allows for consistent comparison with other similar lighting projects. Although intended for lighting retrofit applications, M&V plans developed per this framework document may also be used for other non-lighting technology retrofits and new installations.
Date: November 4, 2009
Creator: Richman, Eric E.
Object Type: Report
System: The UNT Digital Library

Utility Scale Renewables: Renewable and Efficiency Technology Integration (Presentation)

PowerPoint presentation given by Dave Mooney at the NREL Industry Forum on renewable and efficiency technology integration.
Date: November 4, 2009
Creator: Mooney, D.
Object Type: Presentation
System: The UNT Digital Library
Two-electron time-delay interference in atomic double ionization by attosecond pulses (open access)

Two-electron time-delay interference in atomic double ionization by attosecond pulses

A two-color two-photon atomic double ionization experiment using subfemtosecond UV pulses can be designed such that the sequential two-color process dominates and one electron is ejected by each pulse. Nonetheless, ab initio calculations show that, for sufficiently short pulses, a prominent interference pattern in the joint energy distribution of the sequentially ejected electrons can be observed that is due to their indistinguishability and the exchange symmetry of the wave function.
Date: October 4, 2009
Creator: Rescigno, Thomas N
Object Type: Article
System: The UNT Digital Library
MAJORANA Neutrinoless Double-Beta Decay DUSEL R&D (open access)

MAJORANA Neutrinoless Double-Beta Decay DUSEL R&D

The Majorana research and development is addressing key issues and risks related to the collaboration's goal of undertaking a search for neutrinoless double-beta decay (0{nu}{beta}{beta}) in {sup 76}Ge using an array of hyper-pure Ge-diodes (HPGe). The observation of this decay would provide critical insight into our understanding of neutrinos, yielding definitive evidence that neutrinos are Majorana particles and providing information on the absolute mass of neutrinos. Achieving sensitivities to 0{nu}{beta}{beta} decay half-lives on the order of 10{sup 26} years requires ultra-low backgrounds in the 2039 keV region where a 0{nu}{beta}{beta} decay peak would be observed. The goal of our R&D program has been to demonstrate the feasibility of all components of Majorana and to provide an integrated evaluation framework, allowing for optimization of these components in terms of background, background suppression, and signal detection efficiency and acceptance. This report covers work carried out by Majorana collaboration members at the University of Washington as part of the overall Majorana collaboration activities. Specifically the Majorana group at the University of Washington was involved in moving forward on demonstrating technology for clean large-scale cryostats and mounting the HPGe crystals in low-mass holders. The UW activities included assistance in the procurement and assembly of …
Date: September 4, 2009
Creator: Wilkerson, John F.
Object Type: Report
System: The UNT Digital Library
Maximum-Entropy Meshfree Method for Compressible and Near-Incompressible Elasticity (open access)

Maximum-Entropy Meshfree Method for Compressible and Near-Incompressible Elasticity

Numerical integration errors and volumetric locking in the near-incompressible limit are two outstanding issues in Galerkin-based meshfree computations. In this paper, we present a modified Gaussian integration scheme on background cells for meshfree methods that alleviates errors in numerical integration and ensures patch test satisfaction to machine precision. Secondly, a locking-free small-strain elasticity formulation for meshfree methods is proposed, which draws on developments in assumed strain methods and nodal integration techniques. In this study, maximum-entropy basis functions are used; however, the generality of our approach permits the use of any meshfree approximation. Various benchmark problems in two-dimensional compressible and near-incompressible small strain elasticity are presented to demonstrate the accuracy and optimal convergence in the energy norm of the maximum-entropy meshfree formulation.
Date: September 4, 2009
Creator: Ortiz, A.; Puso, M. A. & Sukumar, N.
Object Type: Article
System: The UNT Digital Library
MeDICi: An Open Platform for Sensor Integration (open access)

MeDICi: An Open Platform for Sensor Integration

MeDICi (Middleware for Data Intensive Computing) is a platform for developing high performance, distributed streaming analytic and scientific applications. Developed at Pacific Northwest National Laboratory (PNNL), MeDICi has been released under an open source license and is based on enterprise-proven middleware technologies including a widely used Enterprise Service Bus (ESB), the standard Business Process Execution Language (BPEL), and open source message brokers. Wherever possible, we have built on existing open source, standards-based systems and integrated them into a coherent whole by creating simplified graphical programming tools such as a Workflow Designer and an easy to use and well-documented integration API. This software development approach allows us to: avoid re-creating complex service integration and orchestration systems, reap the benefits of continual improvements to the technology base, and focus on creating tools and APIs which allow for the creation of re-usable component-based software components applications and workflows. These aspects have facilitated rapid adoption of the platform within PNNL for demonstration and operational applications. In fact, MeDICi has been used for a wide range of integration projects including two sensor integration applications described later on in this paper. The remainder of this article white paper is organized as follows: Section 2 provides a …
Date: September 4, 2009
Creator: Wynne, Adam S.; Gorton, Ian; Chase, Jared M. & Stephan, Eric G.
Object Type: Report
System: The UNT Digital Library
A Novel Neutron Imaging Calibration System Using a Neutron Generating Accelerator Tube (open access)

A Novel Neutron Imaging Calibration System Using a Neutron Generating Accelerator Tube

Neutron Imaging is a key diagnostic for use in inertial confinement fusion (ICF) experiments, and has been fielded on experiments at Omega and Z. It will also be a key diagnostics at the National Ignition Facility (NIF) located at Lawrence Livermore National Laboratory (LLNL) and eventually at the Laser Megajoule in France. Most systems are based on a neutron pinhole array placed at the target chamber while it is imaged by a scintillating fiber block. The light output of this scintillator is coupled via a reducer to a fiber bundle which transports the image to a CCD camera. Alternatively some systems use optical lens assemblies to focus the light onto a camera.For ICF applications the neutron imaging systems will primarily look at 14.2 MeV neutrons. However, 2.2 MeV and 20+ MeV neutrons will also be present and will potentially provide key information.
Date: September 4, 2009
Creator: Ali, Z., Davis, B., Tinsley, J. R., Miller, E. K.
Object Type: Article
System: The UNT Digital Library
Remediation of Cr(VI) by biogenic magnetic nanoparticles: An x-ray magnetic circular dichroism study (open access)

Remediation of Cr(VI) by biogenic magnetic nanoparticles: An x-ray magnetic circular dichroism study

Biologically synthesized magnetite (Fe{sub 3}O{sub 4}) nanoparticles are studied using x-ray absorption and x-ray magnetic circular dichroism following exposure to hexavalent Cr solution. By examining their magnetic state, Cr cations are shown to exist in trivalent form on octahedral sites within the magnetite spinel surface. The possibility of reducing toxic Cr(VI) into a stable, non-toxic form, such as a Cr{sup 3+}-spinel layer, makes biogenic magnetite nanoparticles an attractive candidate for Cr remediation.
Date: September 4, 2009
Creator: Telling, N. D.; Coker, V. S.; Cutting, R. S.; van der Laan, G.; Pearce, C. I.; Pattrick, R. A. D. et al.
Object Type: Article
System: The UNT Digital Library