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Automatic Musical Meter Detection, Mikel Gainza Jan 2009

Automatic Musical Meter Detection, Mikel Gainza

Conference papers

A method that automatically estimates the metrical structure of a piece of music is presented. The approach is based on the generation of a beat similarity matrix, which provided information about the similarity between any two beats of a piece of music. The repetitive structure of most music is exploited by processing the beat similarity matrix in order to identify similar patterns of beats in different parts of a piece. This principles proves to be equally effective for the detection of both duple and triple meters as awll as complex meters. The use of beat positions and dynamic programming techniques …


Systems Chemistry And Parrondo’S Paradox: Computational Models Of Thermal Cycling, Daniel C. Osipovitch, Carl Barratt, Pauline M. Schwartz Jan 2009

Systems Chemistry And Parrondo’S Paradox: Computational Models Of Thermal Cycling, Daniel C. Osipovitch, Carl Barratt, Pauline M. Schwartz

Chemistry and Chemical Engineering Faculty Publications

A mathematical concept known as Parrondo’s paradox motivated the development of several novel computational models of chemical systems in which thermal cycling was explored. In these kinetics systems we compared the rates of formation of product under cycling temperature and steady-sate conditions. We found that a greater concentration of product was predicted under oscillating temperature conditions. Our computational models of thermal cycling suggest new applications in chemical and chemical engineering systems.


Delivering Core Engineering Concepts To Secondary Level Students, Chris Merrill, Rodney L. Custer, Jenny Daugherty, Martin Westrick, Yong Zeng Jan 2009

Delivering Core Engineering Concepts To Secondary Level Students, Chris Merrill, Rodney L. Custer, Jenny Daugherty, Martin Westrick, Yong Zeng

Publications

Within primary and secondary school technology education, engineering has been proposed as an avenue to bring about technological literacy (Lewis, 2005; Dearing & Daugherty, 2004). Different initiatives such as curriculum development projects (i.e., Project ProBase and Project Lead The Way) and National Science Foundation funded projects such as the National Center for Engineering and Technology Education (NCETE) have been developed to infuse engineering into primary and secondary education. For example, one key goal of the technology teacher education component of NCETE is to impact the focus and content of the technology education field at the secondary level (National Center for …


Resources - Thinking Small: Nano Small, David Stricker Jan 2009

Resources - Thinking Small: Nano Small, David Stricker

Publications

The article provides information on the "Nanooze" magazine publication. It notes the significance of nanotechnology to the development of latest innovations that come from materials at smallest dimensions or at the nanoscale levels. It presents resources published within the publication that explore the emerging issues in nanotechnology.


Biological Opinion On The Operation Of The Missouri River Main Stem System, Operation And Maintenance Of The Missouri River Bank Stabilization And Navigation Project, And Operation Of The Kansas River Reservoir System Jan 2009

Biological Opinion On The Operation Of The Missouri River Main Stem System, Operation And Maintenance Of The Missouri River Bank Stabilization And Navigation Project, And Operation Of The Kansas River Reservoir System

United States Army Corps of Engineers, Omaha District

The U.S. Army Corps of Engineers (Corps) prepared this Annual Report for interested parties in accordance with reporting recommendations of the Biological Opinion on the Operation of the Missouri River Main Stem System (System), Operation and Maintenance of the Missouri River Bank Stabilization and Navigation Project and Operation of the Kansas River Reservoir System, prepared by the U.S. Fish and Wildlife Service (USFWS), dated November 30, 2000, and the Amendment thereto, dated December 16, 2003 (BiOp). This annual report also documents the Corps’ activities implemented under the Missouri River Bank Stabilization and Navigation Fish and Wildlife Mitigation Project, Iowa, Nebraska, …


Missouri River Recovery - Integrated Science Program Jan 2009

Missouri River Recovery - Integrated Science Program

United States Army Corps of Engineers, Omaha District

Book List

System-wide Status Reports, Guidance Documents & Standard Operating Plans

Pallid Sturgeon

Least Tern and Piping Plover

Flow Modifications

Adaptive Management

Cottonwoods


Biomedical Informatics Research Network (Birn) Data Repository, Laurence Jonathan Bouts Bohannan Jan 2009

Biomedical Informatics Research Network (Birn) Data Repository, Laurence Jonathan Bouts Bohannan

Theses Digitization Project

The primary goal of this project was to streamline the submission process for researchers to categorize, approve, curate, and publish these data sets. By supporting the sharing and exchange of these data types in fulfillment of the National Institute of Health guidelines the BIRN Data Repository will have the ability to grow as the need develops for these researchers to easily share information.


A Theoretical Framework To Guide The Re-Engineering Of Technology Education, Todd R. Kelley, Nadia Kellam Jan 2009

A Theoretical Framework To Guide The Re-Engineering Of Technology Education, Todd R. Kelley, Nadia Kellam

Publications

Before leaders in technology education are able to identify a theoretical framework upon which a curriculum is to stand, they must first grapple with two opposing views of the purpose of technology education – education for all learners or career/technical education. Dakers (2006) identifies two opposing philosophies that can serve as a framework for technology education, both inspired by ancient Greece, with the works of Descartes and the birth of positivism. Later reappearing in Pascal’s writings of the mathematical mind, and finally with Rousseau in the mid 1700s, the theoretical arguments of academic verses vocational were established in education, and …


A Case Study Of The Implementation Of An Engineering Program Into A High School Technology Education Classroom, Steven Shumway, Geoff Wright Jan 2009

A Case Study Of The Implementation Of An Engineering Program Into A High School Technology Education Classroom, Steven Shumway, Geoff Wright

Reports of Center Studies

Using a case study format, our objective was to collect data related to the following research questions:

- What criteria do teachers and districts use when selecting engineering design experiences for infusion into high school classes and which of these criteria are most effective?

- What issues, opportunities, and constraints do teachers confront as they infuse engineering concepts into technology education?


Archetype Alignment: A Two-Level Driven Semantic Matching Approach To Interoperability In The Clinical Domain, Damon Berry, Jesus Bisbal Jan 2009

Archetype Alignment: A Two-Level Driven Semantic Matching Approach To Interoperability In The Clinical Domain, Damon Berry, Jesus Bisbal

Conference Papers

Semantic interoperability between electronic health record systems and other information systems in the health domain implies agreement about the structure and the meaning of the information that is communicated. There are still a number of similar but different EHR system approaches. Some of the newer approaches adopt the two-layer model approach where a generic reference model is constrained by archetypes into valid clinical concepts which can be exchanged. The meaning of the concepts that are represented by an archetype can be conveyed by embedding codes from a commonly recognised terminology at appropriate points in the archetype. However, as the number …


Heterogeneous Drive Mechanisms For Novel Locomotion In Rough Terrain, Roy Godzdanker Jan 2009

Heterogeneous Drive Mechanisms For Novel Locomotion In Rough Terrain, Roy Godzdanker

Electronic Theses and Dissertations

The smaller the robot the easier it is for it to access voids in a collapsed structure, however small size brings a host of other problems related to constrained resources. One of the primary constraints on small robots is limited motive power to surmount obstacles and navigate rough terrain. This thesis examines the addition of bulk motive force actuators to existing locomotion platforms and the impact of these heterogeneous actuators on conventional steering methods. The steering methods examined are those associated with skid steered vehicles and differential drive vehicles. In developing the Crabinator, a robot composed of a limbed crawler …


Nitrogen Removal And Sustainability Of Vertical Flow Constructed Wetlands For Small Scale Wastewater Treatment, Valerie J. Fuchs Jan 2009

Nitrogen Removal And Sustainability Of Vertical Flow Constructed Wetlands For Small Scale Wastewater Treatment, Valerie J. Fuchs

Dissertations, Master's Theses and Master's Reports - Open

The challenge for wastewater professionals is to design and operate treatment processes that support human well being and are environmentally sensitive throughout the life-cycle. This research focuses on one technology for small-scale wastewater treatment: the vertical flow constructed wetland (VFCW), which is herein investigated for the capacity to remove ammonium and nitrate nitrogen from wastewater. Hydraulic regime and presence/absence of vegetation are the basis for a three-phase bench scale experiment to determine oxygen transfer and nitrogen fate in VFCWs. Results show that 90% NH4+-N removal is achieved in aerobic downflow columns, 60% NO3--N removal occurs in anaerobic upflow columns, and …


Post Treatment Alternatives For Stabilizing Desalinated Water, Susaye Douglas Jan 2009

Post Treatment Alternatives For Stabilizing Desalinated Water, Susaye Douglas

Electronic Theses and Dissertations

The use of brackish water and seawater desalination for augmenting potable water supplies has focused primarily on pre-treatment, process optimization, energy efficiency, and concentrate management. Much less has been documented regarding the impact of post-treatment requirements with respect to distribution system. The goals of this study were to review current literature on post-treatment of permeate water, use survey questionnaires to gather information on post-treatment water quality characteristics, gather operation information, review general capital and maintenance cost, and identify appropriate "lessons learned" with regards to post-treatment from water purveyors participating in the Project. A workshop was organized where experts from across …


Effect Of Finite Geometry On Solidification Microstructure In Beam-Based Fabrication Of Thin Wall Structures, Satish C. Kuchi Jan 2009

Effect Of Finite Geometry On Solidification Microstructure In Beam-Based Fabrication Of Thin Wall Structures, Satish C. Kuchi

Browse all Theses and Dissertations

With the advent of Rapid Protyping (RP) in the manufacturing industry, many newtechnologies came into development for quick fabrication of materials. One of the most versatile fabrication process among them is additive manufacturing. Laser based manufacturing (LBM) and electron beam manufacturing (EBM) processes use the energy from a laser or electron beam to build up structures layer by layer directly from powdered metals and wire feed stock. It has been determined from previous work that solidification cooling rate and thermal gradients are the important factors for controlling microstructure (grain size and morphology) and resulting mechanical properties of the deposit. The …


Development Of A Focused Broadband Ultrasonic Transducer For High Resolution Fundamental And Harmonic Intravascular Imaging, Chaitanya K. Chandrana Jan 2009

Development Of A Focused Broadband Ultrasonic Transducer For High Resolution Fundamental And Harmonic Intravascular Imaging, Chaitanya K. Chandrana

ETD Archive

Intravascular ultrasound (IVUS) is increasingly employed for detection and evaluation of coronary artery diseases. Tissue Harmonic Imaging provides different tissue information that could additionally be used to improve diagnostic accuracy. However, current IVUS systems, with their unfocussed transducers, may not be capable of operating in harmonic imaging mode. Thus, there is a need to develop suitable transducers and appropriate techniques to allow imaging in multi modes for complementary diagnostic information. Focused PVDF TrFE transducers were developed using MEMS (Micro-Electro-Mechanical-Systems) compatible protocols. The transducers were characterized using pulse-echo techniques and exhibited broad bandwidth (110 at -6dB) with axial resolutions of Such …


Imaging Of Tyramine-Substituted Hydrogels For Tissue Replacement, Ediuska V. Laurens Jan 2009

Imaging Of Tyramine-Substituted Hydrogels For Tissue Replacement, Ediuska V. Laurens

ETD Archive

Novel tyramine-based hyaluronan (HA) and collagen hydrogels have been developed in which cross-linking is accomplished via peroxidase-mediated dityramine linkages allowing direct cross-linking in vivo. These TB hydrogels possess advantageous physical properties, which include excellent biocompatibility and the ability to mimic the biological, structural and mechanical properties of normal, healthy tissues, including cartilage, and thus provide for synthetic, implantable biomaterials suitable for a wide range of tissue types. The efficacy of these TB-hydrogels has been previously tested in a number of clinically relevant animal models, which have evaluated their applicability for the repair/replacement of various tissues, including cartilage. Nevertheless, there exists …


Two Approaches For Cell Retention In Perfusion Culture Systems, Zhaowei Wang Jan 2009

Two Approaches For Cell Retention In Perfusion Culture Systems, Zhaowei Wang

ETD Archive

A lack of efficient, economical, and reliable cell retention devices has limited the application of perfusion culture systems in the biopharmaceutical industry. Two types of cell retention devices were developed in this work for long-term perfusion culture systems: a modification of an inclined gravity settler and a variation of an ultrasonic filter. Both bench-top and large-scale tests showed that the gravity settler can effectively retain viable cells and preferentially remove nonviable cells in perfusion culture systems. The viable cell retention rate can be maintained well above 90 during long-term perfusion culture period while the nonviable cell retention rate is 20-30 …


Cortical Bone Tissue Engineering;Scaffold Design And Cell Selection, Demin Wen Jan 2009

Cortical Bone Tissue Engineering;Scaffold Design And Cell Selection, Demin Wen

ETD Archive

Cortical bone tissue engineering provides a promising approach to generate graft materials needed to treat the large sized bone defects. The underling premise of tissue engineering is to mimic the in vivo microenvironment as best as possible in vitro culture system. To select an appropriate scaffold material used in this model system, mechanical and hydraulic permeability properties of 316L porous stainless steel and polymethylmethacrylate (PMMA) were studied, as well as their biocompatibility in short and long term cell culture. Results showed that scaffolds made of both stainless steel and PMMA: (1) could be manufactured to have similar permeability as that …


The Synthesis And Characterization Of Novel Elastin-Like Polypeptides Containing An Oligomerization Domain, James T. Cole Jan 2009

The Synthesis And Characterization Of Novel Elastin-Like Polypeptides Containing An Oligomerization Domain, James T. Cole

ETD Archive

Elastin like polypeptides (ELPs) are an emerging class of biomaterials due to their unique group of chemical, physical and biological properties. We have constructed a library of ELPs based on the pentapeptide amino acid repeat sequence (GVGVP). ELPs exhibit lower critical solution temperature (LCST) transition behavior from a soluble phase below the transition temperature (Tt) to an insoluble two phase system above the transition temperature. This process is completely reversible so that ELPs can become soluble again upon lowering the temperature. This temperature can be tuned in many different ways at the molecular level by changing the composition of the …


Biological Treatment Of Dietary Supplement Wastewater, Erick Benjamin Butler Jan 2009

Biological Treatment Of Dietary Supplement Wastewater, Erick Benjamin Butler

ETD Archive

Dietary supplement wastewater contains higher order polysaccharides such as the complex sugars maltodextrin and low fat milk. These complex sugars contain a significant amount of organic carbon therefore, presence of these sugars can pose threats to the environment if discharged without treatment. While many food processing plants are required to send their waste through wastewater treatment, legislation may require preliminary treatment of these wastes in order to satisfy the effluent discharge requirements. Because of the high organic carbon presence, it would be preferable to use biological treatment methods to reduce the organics present within the system. Microorganisms are capable of …


Tomato Bushy Stunt Virus (Tbsv), A Versatile Platform For Polyvalent Display Of Antigenic Epitopes And Vaccine Design, Shantanu Kumar, Wendy Ochoa, Pratik Singh, Catherine Hsu, Anette Schneemann, Marianne Manchester, Mark Olson, Vijay Reddy Jan 2009

Tomato Bushy Stunt Virus (Tbsv), A Versatile Platform For Polyvalent Display Of Antigenic Epitopes And Vaccine Design, Shantanu Kumar, Wendy Ochoa, Pratik Singh, Catherine Hsu, Anette Schneemann, Marianne Manchester, Mark Olson, Vijay Reddy

United States Army: Publications

Viruses-like particles (VLPs) are frequently being used as platforms for polyvalent display of foreign epitopes of interest on their capsid surface to improve their presentation enhancing the antigenicity and host immune response. In the present study, we used the VLPs of Tomato bushy stunt virus (TBSV), an icosahedral plant virus, as a platform to display 180 copies of 16 amino acid epitopes of ricin toxin fused to the C-terminal end of a modified TBSV capsid protein (NΔ52). Expression of the chimeric recombinant protein in insect cells resulted in spontaneous assembly of VLPs displaying the ricin epitope. Cryo-electron microscopy and image …


Complementary And Alternative Medicine For The Allergist-Immunologist: Where Do I Start?, Renata J. M. Engler, Catherine M. With, Philip J. Gregory, Jeff M. Jellin Jan 2009

Complementary And Alternative Medicine For The Allergist-Immunologist: Where Do I Start?, Renata J. M. Engler, Catherine M. With, Philip J. Gregory, Jeff M. Jellin

United States Army: Publications

Complementary and alternative medicine (CAM) therapies present a growing information management challenge for physicians because nearly 40% of their patients may be using and another 50% may be considering use of CAM as part of their health care regimen. The National Health Statistics Reports for 2007 described the most commonly used nonvitamin, nonmineral therapy as natural products (eg, herbals at 17.7%). More than5% of children under the age of 18 years used CAM for allergic conditions including asthma. The amount and quality of information available and concerns about liability risk represent a challenge for most physicians. This review focuses on …


Selecting And Conserving Lands For Biodiversity: The Role Of Remote Sensing, John Wiens, Robert Sutter, Mark Anderson, Jon Blanchard, Analie Barnett, Naikoa Aguilar-Amuchastegui, Chadwick Avery, Stephen Laine Jan 2009

Selecting And Conserving Lands For Biodiversity: The Role Of Remote Sensing, John Wiens, Robert Sutter, Mark Anderson, Jon Blanchard, Analie Barnett, Naikoa Aguilar-Amuchastegui, Chadwick Avery, Stephen Laine

United States Air Force: Publications

A major focus of conservation is on protecting areas to ensure the persistence of biological diversity. Because such areas may be large, not easily accessible, subject to change, and sensitive to the surrounding landscape, remote sensing can be a valuable tool in establishing and managing protected areas. We describe three case studies to illustrate how remote sensing can contribute to setting priorities for conservation actions, monitoring the status of conservation targets, and evaluating the effectiveness of conservation strategies. In the Connecticut River watershed, remote sensing has been used to assess flood regimes and identify key areas of floodplain forests and …


Educating Engineers: A History Of Engineering Education At Valparaiso University, Edgar J. Luecke Jan 2009

Educating Engineers: A History Of Engineering Education At Valparaiso University, Edgar J. Luecke

Engineering Faculty Publications, Patents, Presentations

No abstract provided.


Surface-Initiated Titanium-Mediated Coordination Polymerization From Catalyst-Functionalized Single And Multiwalled Carbon Nanotubes, Dimitrios Priftis, Nikolaos Petzetakis, Georgios Sakellariou, Marinos Pitsikalis, Durairaj Baskaran, Jimmy W. Mays, Nikos Hadjichristidis Jan 2009

Surface-Initiated Titanium-Mediated Coordination Polymerization From Catalyst-Functionalized Single And Multiwalled Carbon Nanotubes, Dimitrios Priftis, Nikolaos Petzetakis, Georgios Sakellariou, Marinos Pitsikalis, Durairaj Baskaran, Jimmy W. Mays, Nikos Hadjichristidis

United States Department of Energy: Publications

Single (SWNTs) and multiwalled (MWNTs) carbon nanotubes were functionalized with a titanium alkoxide catalyst through a Diels-Alder cycloaddition reaction. The catalyst-functionalized carbon nanotubes (CNTs) were used for the surface initiated titanium-mediated coordination polymerizations of L-lactide (L-LA), ε-caprolactone (ε-CL) and n-hexyl isocyanate (HIC) employing the “grafting from” technique. 1H NMR, IR and Raman spectra showed that the precursor catalyst was successfully synthesized and covalently attached on the CNTs surface. Thermogravimetric analysis (TGA) revealed that the grafted poly(L-lactide) (PLLA) content could be controlled with time. The final polymer-grafted CNTs were readily dissolved in organic solvents as compared to the insoluble pristine …


Biomineralization Associated With Microbial Reduction Of Fe3+ And Oxidation Of Fe2+ In Solid Minerals, Gengxin Zhang, Hailiang Dong, Hongchen Jiang, Ravi K. Kukkadapu, Jinwook Kim, Dennis Eberl, Zhiqin Xu Jan 2009

Biomineralization Associated With Microbial Reduction Of Fe3+ And Oxidation Of Fe2+ In Solid Minerals, Gengxin Zhang, Hailiang Dong, Hongchen Jiang, Ravi K. Kukkadapu, Jinwook Kim, Dennis Eberl, Zhiqin Xu

United States Department of Energy: Publications

Iron-reducing and oxidizing microorganisms gain energy through reduction or oxidation of iron, and by doing so play an important role in the geochemical cycling of iron. This study was undertaken to investigate mineral transformations associated with microbial reduction of Fe3+ and oxidation of Fe2+ in solid minerals. A fluid sample from the 2450 m depth of the Chinese Continental Scientific Drilling project was collected, and Fe3+-reducing and Fe2+-oxidizing microorganisms were enriched. The enrichment cultures displayed reduction of Fe3+ in nontronite and ferric citrate, and oxidation of Fe2+ in vivianite, siderite, and monosulfide …


Reduction And Long-Term Immobilization Of Technetium By Fe(Ii) Associated With Clay Mineral Nontronite, Deb Jaisi, Hailiang Dong, Andrew Plymale, James K. Fredrickson, John M. Zachara, Steve Heald, Chongxuan Liu Jan 2009

Reduction And Long-Term Immobilization Of Technetium By Fe(Ii) Associated With Clay Mineral Nontronite, Deb Jaisi, Hailiang Dong, Andrew Plymale, James K. Fredrickson, John M. Zachara, Steve Heald, Chongxuan Liu

United States Department of Energy: Publications

99Tc is formed mostly during nuclear reactions and is released into the environment during weapons testing and inadvertent waste disposal. The long half-life, high environmental mobility (as Tc(VII)O4−) and its possible uptake into the food chain cause 99Tc to be a significant environmental contaminant. In this study, we evaluated the role of Fe(II) in biologically reduced clay mineral, nontronite (NAu-2), in reducing Tc(VII) O4− to poorly soluble Tc(IV) species as a function of pH and Fe(II) concentration. The rate of Tc(VII) reduction by Fe(II) in NAu-2 was higher at neutral pH (pH 7.0) …


Electron Donor-Dependent Radionuclide Reduction And Nanoparticle Formation By Anaeromyxobacter Dehalogenans Strain 2cp-C, Matthew J. Marshall, Alice C. Dohnalkova, David Kennedy, Andrew Plymale, Sara Thomas, Frank Löffler, Robert Sanford, John M. Zachara, James K. Fredrickson, Alexander Beliaev Jan 2009

Electron Donor-Dependent Radionuclide Reduction And Nanoparticle Formation By Anaeromyxobacter Dehalogenans Strain 2cp-C, Matthew J. Marshall, Alice C. Dohnalkova, David Kennedy, Andrew Plymale, Sara Thomas, Frank Löffler, Robert Sanford, John M. Zachara, James K. Fredrickson, Alexander Beliaev

United States Department of Energy: Publications

Anaeromyxobacter dehalogenans strain 2CP-C reduces U(VI) and Tc(VII) to U(IV)O2(s) (uraninite) and Tc(IV)O2(S) respectively. Kinetic studies with resting cells revealed that U(VI) or Tc(VII) reduction rates using H2 as electron donor exceeded those observed in acetate-amended incubations. The reduction of U(VI) by A. dehalogenans 2CP-C resulted in extracellular accumulation of ~5 nm uraninite nanoparticles in association with a lectin-binding extracellular polymeric substance (EPS). The electron donor did not affect UO2(S) nanoparticle size or association with EPS, but the utilization of acetate as the source of reducing equivalents resulted in distinct UO2(S) nanoparticle aggregates that were ~50 …


The Roles Of Outer Membrane Cytochromes Of Shewanella And Geobacter In Extracellular Electron Transfer, Liang Shi, David J. Richardson, Zheming Wang, Sebastien Kerisit, Kevin Rosso, John M. Zachara, James K. Fredrickson Jan 2009

The Roles Of Outer Membrane Cytochromes Of Shewanella And Geobacter In Extracellular Electron Transfer, Liang Shi, David J. Richardson, Zheming Wang, Sebastien Kerisit, Kevin Rosso, John M. Zachara, James K. Fredrickson

United States Department of Energy: Publications

As key components of the electron transfer (ET) pathways used for dissimilatory reduction of solid iron [Fe(III)] (hydr)oxides, outer membrane multihaem c-type cytochromes MtrC and OmcA of Shewanella oneidensis MR-1 and OmcE and OmcS of Geobacter sulfurreducens mediate ET reactions extracellularly. Both MtrC and OmcA are at least partially exposed to the extracellular side of the outer membrane and their translocation across the outer membrane is mediated by bacterial type II secretion system. Purified MtrC and OmcA can bind Fe(III) oxides, such as haematite (α-Fe2O3), and directly transfer electrons to the haematite surface. Bindings of …


Uranium Speciation As A Function Of Depth In Contaminated Hanford Sediments - A Micro-Xrf, Micro-Xrd, And Micro- And Bulk-Xafs Study, David Singer, John M. Zachara, Gordon Brown Jan 2009

Uranium Speciation As A Function Of Depth In Contaminated Hanford Sediments - A Micro-Xrf, Micro-Xrd, And Micro- And Bulk-Xafs Study, David Singer, John M. Zachara, Gordon Brown

United States Department of Energy: Publications

The distribution and speciation of U and Cu in contaminated vadose zone and aquifer sediments from the U.S. DOE Hanford site (300 Area) were determined using a combination of synchrotron-based micro-X-ray fluorescence (μXRF) imaging, micro-X-ray absorption near edge structure (μXANES) spectroscopy, and micro-X-ray diffraction (μXRD) techniques combined with bulk U LIII-edge X-ray absorption fine structure (XAFS) spectroscopy. Samples were collected from within the inactive North Process Pond (NPP2) at 8 ft (2.4 m, NPP2-8) depth and 12 ft (3.7 m, NPP2-12) depth in the vadose zone, and fines were isolated from turbid groundwater just below the water Table …