ACRF Instrumentation Status: New, Current, and Future - January 2009 (open access)

ACRF Instrumentation Status: New, Current, and Future - January 2009

The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.
Date: March 2, 2009
Creator: Voyles, J. W.
Object Type: Report
System: The UNT Digital Library
Alaska Wood Biomass Energy Project Final Report (open access)

Alaska Wood Biomass Energy Project Final Report

The purpose of the Craig Wood Fired Boiler Project is to use waste wood from local sawmilling operations to provide heat to local public buildings, in an effort to reduce the cost of operating those buildings, and put to productive use a byproduct from the wood milling process that otherwise presents an expense to local mills. The scope of the project included the acquisition of a wood boiler and the delivery systems to feed wood fuel to it, the construction of a building to house the boiler and delivery systems, and connection of the boiler facility to three buildings that will benefit from heat generated by the boiler: the Craig Aquatic Center, the Craig Elementary School, and the Craig Middle School buildings.
Date: March 2, 2009
Creator: Bolling, Jonathan
Object Type: Report
System: The UNT Digital Library
Atomic Resolution Imaging with a sub-50 pm Electron Probe (open access)

Atomic Resolution Imaging with a sub-50 pm Electron Probe

Using a highly coherent focused electron probe in a 5th order aberration-corrected transmission electron microscope, we report on resolving a crystal spacing less than 50 pm. Based on the geometrical source size and residual coherent and incoherent axial lens aberrations, an electron probe is calculated, which is theoretically capable of resolving an ideal 47 pm spacing with 29percent contrast. Our experimental data show the 47 pm spacing of a Ge 114 crystal imaged with 11-18percent contrast at a 60-95percent confidence level, providing the first direct evidence for sub 50-pm resolution in ADF STEM imaging.
Date: March 2, 2009
Creator: Erni, Rolf P.; Rossell, Marta D.; Kisielowski, Christian & Dahmen, Ulrich
Object Type: Article
System: The UNT Digital Library
Filtration and Leach Testing for PUREX Cladding Sludge and REDOX Cladding Sludge Actual Waste Sample Composites (open access)

Filtration and Leach Testing for PUREX Cladding Sludge and REDOX Cladding Sludge Actual Waste Sample Composites

A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan (Barnes and Voke 2006). The test program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Hanford Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Under test plan TP RPP WTP 467 (Fiskum et al. 2007), eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. Under this test plan, a waste testing program was implemented that included: • Homogenizing the archive samples by group as defined in the test plan. • Characterizing the homogenized sample groups. • Performing parametric leaching testing on each group for compounds of interest. • Performing bench-top filtration/leaching tests in the hot cell for each group to simulate filtration and leaching activities if they occurred in the UFP2 vessel of the WTP Pretreatment Facility. This report focuses on a filtration/leaching test performed using two of the eight waste composite samples. The sample groups examined in this report …
Date: March 2, 2009
Creator: Shimskey, Rick W.; Billing, Justin M.; Buck, Edgar C.; Casella, Amanda J.; Crum, Jarrod V.; Daniel, Richard C. et al.
Object Type: Report
System: The UNT Digital Library
High-frequency surface acoustic wave propagation in nanaostructures characterized by coherent extreme ultraviolet beams (open access)

High-frequency surface acoustic wave propagation in nanaostructures characterized by coherent extreme ultraviolet beams

We study ultrahigh frequency surface acoustic wave propagation in nickel-on-sapphire nanostructures. The use of ultrafast, coherent, extreme ultraviolet beams allows us to extend optical measurements of propagation dynamics of surface acoustic waves to frequencies of nearly 50 GHz, corresponding to wavelengths as short as 125 nm. We repeat the measurement on a sequence of nanostructured samples to observe surface acoustic wave dispersion in a nanostructure series for the first time. These measurements are critical for accurate characterization of thin films using this technique.
Date: March 2, 2009
Creator: Siemens, M.; Li, Q.; Murnane, M.; Kapteyn, H.; Yang, R.; Anderson, E. et al.
Object Type: Article
System: The UNT Digital Library
HYDROGEN TECHNOLOGY RESEARCH AT THE SAVANNAH RIVER NATIONAL LABORATORY (open access)

HYDROGEN TECHNOLOGY RESEARCH AT THE SAVANNAH RIVER NATIONAL LABORATORY

The Savannah River National Laboratory (SRNL) is a U.S. Department of Energy research and development laboratory located at the Savannah River Site (SRS) near Aiken, South Carolina. SRNL has over 50 years of experience in developing and applying hydrogen technology, both through its national defense activities as well as through its recent activities with the DOE Hydrogen Programs. The hydrogen technical staff at SRNL comprises over 90 scientists, engineers and technologists, and it is believed to be the largest such staff in the U.S. SRNL has ongoing R&D initiatives in a variety of hydrogen storage areas, including metal hydrides, complex hydrides, chemical hydrides and carbon nanotubes. SRNL has over 25 years of experience in metal hydrides and solid-state hydrogen storage research, development and demonstration. As part of its defense mission at SRS, SRNL developed, designed, demonstrated and provides ongoing technical support for the largest hydrogen processing facility in the world based on the integrated use of metal hydrides for hydrogen storage, separation, and compression. The SRNL has been active in teaming with academic and industrial partners to advance hydrogen technology. A primary focus of SRNL's R&D has been hydrogen storage using metal and complex hydrides. SRNL and its Hydrogen Technology …
Date: March 2, 2009
Creator: Danko, E
Object Type: Article
System: The UNT Digital Library
The IceCube data acquisition system: Signal capture, digitization,and timestamping (open access)

The IceCube data acquisition system: Signal capture, digitization,and timestamping

IceCube is a km-scale neutrino observatory under construction at the South Pole with sensors both in the deep ice (InIce) and on the surface (IceTop). The sensors, called Digital Optical Modules (DOMs), detect, digitize and timestamp the signals from optical Cherenkov-radiation photons. The DOM Main Board (MB) data acquisition subsystem is connected to the central DAQ in the IceCube Laboratory (ICL) by a single twisted copper wire-pair and transmits packetized data on demand. Time calibration ismaintained throughout the array by regular transmission to the DOMs of precisely timed analog signals, synchronized to a central GPS-disciplined clock. The design goals and consequent features, functional capabilities, and initial performance of the DOM MB, and the operation of a combined array of DOMs as a system, are described here. Experience with the first InIce strings and the IceTop stations indicates that the system design and performance goals have been achieved.
Date: March 2, 2009
Creator: Collaboration, The IceCube & Matis, Howard
Object Type: Article
System: The UNT Digital Library
Measurement of quasi-ballistic heat transport across nanoscale interfaces using ultrafast coherent soft x-ray beams (open access)

Measurement of quasi-ballistic heat transport across nanoscale interfaces using ultrafast coherent soft x-ray beams

Understanding heat transport on nanoscale dimensions is important for fundamental advances in nanoscience, as well as for practical applications such as thermal management in nano-electronics, thermoelectric devices, photovoltaics, nanomanufacturing, as well as nanoparticle thermal therapy. Here we report the first time-resolved measurements of heat transport across nanostructured interfaces. We observe the transition from a diffusive to a ballistic thermal transport regime, with a corresponding increase in the interface resistivity for line widths smaller than the phonon mean free path in the substrate. Resistivities more than three times higher than the bulk value are measured for the smallest line widths of 65 nm. Our findings are relevant to the modeling and design of heat transport in nanoscale engineered systems, including nanoelectronics, photovoltaics and thermoelectric devices.
Date: March 2, 2009
Creator: Siemens, M.; Li, Q.; Yang, R.; Nelson, K.; Anderson, E.; Murnane, M. et al.
Object Type: Article
System: The UNT Digital Library
Observation of Two-source Interference in the Photoproduction Reaction AuAu --> AuAu rho 0 (open access)

Observation of Two-source Interference in the Photoproduction Reaction AuAu --> AuAu rho 0

In ultra-peripheral relativistic heavy-ion collisions, a photon from the electromagnetic field of one nucleus can fluctuate to a quark-antiquark pair and scatter from the other nucleus, emerging as a {rho}{sup 0}. The {rho}{sup 0} production occurs in two well-separated (median impact parameters of 20 and 40 fermi for the cases considered here) nuclei, so the system forms a 2-source interferometer. At low transverse momenta, the two amplitudes interfere destructively, suppressing {rho}{sup 0} production. Since the {rho}{sup 0} decays before the production amplitudes from the two sources can overlap, the two-pion system can only be described with an entangled non-local wave function, and is thus an example of the Einstein-Podolsky-Rosen paradox. We observe this suppression in 200 GeV per nucleon-pair gold-gold collisions. The interference is 87% {+-} 5%(stat.) {+-} 8% (syst.) of the expected level. This translates into a limit on decoherence due to wave function collapse or other factors, of 23% at the 90% confidence level.
Date: March 2, 2009
Creator: STAR Collaboration
Object Type: Article
System: The UNT Digital Library
Particle-In-Cell/Monte Carlo Simulation of Ion Back Bombardment in Photoinjectors (open access)

Particle-In-Cell/Monte Carlo Simulation of Ion Back Bombardment in Photoinjectors

In this paper, we report on studies of ion back bombardment in high average current dc and rf photoinjectors using a particle-in-cell/Monte Carlo method. Using H{sub 2} ion as an example, we observed that the ion density and energy deposition on the photocathode in rf guns are order of magnitude lower than that in a dc gun. A higher rf frequency helps mitigate the ion back bombardment of the cathode in rf guns.
Date: March 2, 2009
Creator: Qiang, Ji; Corlett, John & Staples, John
Object Type: Article
System: The UNT Digital Library
Spawning Habitat Studies of Hanford Reach Fall Chinook Salmon (Oncorhynchus tshawytscha), Final Report. (open access)

Spawning Habitat Studies of Hanford Reach Fall Chinook Salmon (Oncorhynchus tshawytscha), Final Report.

The Pacific Northwest National Laboratory conducted this study for the Bonneville Power Administration (BPA) with funding provided through the Northwest Power and Conservation Council(a) and the BPA Fish and Wildlife Program. The study was conducted in the Hanford Reach of the Columbia River. The goal of study was to determine the physical habitat factors necessary to define the redd capacity of fall Chinook salmon that spawn in large mainstem rivers like the Hanford Reach and Snake River. The study was originally commissioned in FY 1994 and then recommissioned in FY 2000 through the Fish and Wildlife Program rolling review of the Columbia River Basin projects. The work described in this report covers the period from 1994 through 2004; however, the majority of the information comes from the last four years of the study (2000 through 2004). Results from the work conducted from 1994 to 2000 were covered in an earlier report. More than any other stock of Pacific salmon, fall Chinook salmon (Oncorhynchus tshawytscha) have suffered severe impacts from the hydroelectric development in the Columbia River Basin. Fall Chinook salmon rely heavily on mainstem habitats for all phases of their life cycle, and mainstem hydroelectric dams have inundated or blocked …
Date: March 2, 2009
Creator: Geist, David R.; Arntzen, Evan V. & Chien, Yi-Ju (Pacific Northwest National Laboratory)
Object Type: Report
System: The UNT Digital Library
Sub-10 nm Platinum Nanocrystals with Size and Shape Control: Catalytic Study for Ethylene and Pyrrole Hydrogenation (open access)

Sub-10 nm Platinum Nanocrystals with Size and Shape Control: Catalytic Study for Ethylene and Pyrrole Hydrogenation

Platinum nanocubes and nanopolyhedra with tunable size from 5 to 9 nm were synthesized by controlling the reducing rate of metal precursor ions in a one-pot polyol synthesis. A two-stage process is proposed for the simultaneous control of size and shape. In the first stage, the oxidation state of the metal ion precursors determined the nucleation rate and consequently the number of nuclei. The reaction temperature controlled the shape in the second stage by regulation of the growth kinetics. These well-defined nanocrystals were loaded into MCF-17 mesoporous silica for examination of catalytic properties. Pt loadings and dispersions of the supported catalysts were determined by elemental analysis (ICP-MS) and H2 chemisorption isotherms, respectively. Ethylene hydrogenation rates over the Pt nanocrystals were independent of both size and shape and comparable to Pt single crystals. For pyrrole hydrogenation, the nanocubes enhanced ring-opening ability and thus showed a higher selectivity to n-butylamine as compared to nanopolyhedra.
Date: March 2, 2009
Creator: Tsung, Chia-Kuang; Kuhn, John N.; Huang, Wenyu; Aliaga, Cesar; Hung, Ling-I; Somorjai, Gabor A. et al.
Object Type: Article
System: The UNT Digital Library
X-ray Emission Spectroscopy to Study Ligand Valence Orbitals in Mn Coordination Complexes (open access)

X-ray Emission Spectroscopy to Study Ligand Valence Orbitals in Mn Coordination Complexes

We discuss a spectroscopic method to determine the character of chemical bonding and for the identification of metal ligands in coordination and bioinorganic chemistry. It is based on the analysis of satellite lines in X-ray emission spectra that arise from transitions between valence orbitals and the metal ion 1s level (valence-to-core XES). The spectra, in connection with calculations based on density functional theory (DFT), provide information that is complementary to other spectroscopic techniques, in particular X-ray absorption (XANES and EXAFS). The spectral shape is sensitive to protonation of ligands and allows ligands, which differ only slightly in atomic number (e.g., C, N, O...), to be distinguished. A theoretical discussion of the main spectral features is presented in terms of molecular orbitals for a series of Mn model systems: [Mn(H2O)6]2+, [Mn(H2O)5OH]+, [Mn(H2O)5NH2]+, and [Mn(H2O)5NH3]2+. An application of the method, with comparison between theory and experiment, is presented for the solvated Mn2+ ion in water and three Mn coordination complexes, namely [LMn(acac)N3]BPh4, [LMn(B2O3Ph2)(ClO4)], and [LMn(acac)N]BPh4, where L represents 1,4,7-trimethyl-1,4,7-triazacyclononane, acac stands for the 2,4-pentanedionate anion, and B2O3Ph2 represents the 1,3-diphenyl-1,3-dibora-2-oxapropane-1,3-diolato dianion.
Date: March 2, 2009
Creator: Smolentsev, Grigory; Soldatov, Alexander V; Messinger, Johannes; Merz, Kathrin; Weyhermuller, Thomas; Bergmann, Uwe et al.
Object Type: Article
System: The UNT Digital Library
Aerosols and clouds in chemical transport models and climate models. (open access)

Aerosols and clouds in chemical transport models and climate models.

Clouds exert major influences on both shortwave and longwave radiation as well as on the hydrological cycle. Accurate representation of clouds in climate models is a major unsolved problem because of high sensitivity of radiation and hydrology to cloud properties and processes, incomplete understanding of these processes, and the wide range of length scales over which these processes occur. Small changes in the amount, altitude, physical thickness, and/or microphysical properties of clouds due to human influences can exert changes in Earth's radiation budget that are comparable to the radiative forcing by anthropogenic greenhouse gases, thus either partly offsetting or enhancing the warming due to these gases. Because clouds form on aerosol particles, changes in the amount and/or composition of aerosols affect clouds in a variety of ways. The forcing of the radiation balance due to aerosol-cloud interactions (indirect aerosol effect) has large uncertainties because a variety of important processes are not well understood precluding their accurate representation in models.
Date: March 2, 2008
Creator: Lohmann,U. & Schwartz, S. E.
Object Type: Article
System: The UNT Digital Library
RESIDENTIAL THERMOSTATS: COMFORT CONTROLS IN CALIFORNIA HOMES (open access)

RESIDENTIAL THERMOSTATS: COMFORT CONTROLS IN CALIFORNIA HOMES

This report summarizes results of a literature review, a workshop, and many meetings with demand response and thermostat researchers and implementers. The information obtained from these resources was used to identify key issues of thermostat performance from both energy savings and peak demand perspectives. A research plan was developed to address these issues and activities have already begun to pursue the research agenda.
Date: March 2, 2008
Creator: Meier, Alan K. & Walker, Iain
Object Type: Report
System: The UNT Digital Library
Future Science Needs and Opportunities for Electron Scattering: Next-Generation Instrumentation and Beyond. Report of the Basic Energy Sciences Workshop on Electron Scattering for Materials Characterization, March 1-2, 2007 (open access)

Future Science Needs and Opportunities for Electron Scattering: Next-Generation Instrumentation and Beyond. Report of the Basic Energy Sciences Workshop on Electron Scattering for Materials Characterization, March 1-2, 2007

To identify emerging basic science and engineering research needs and opportunities that will require major advances in electron-scattering theory, technology, and instrumentation.
Date: March 2, 2007
Creator: Miller, D. J.; Williams, D. B.; Anderson, I. M.; Schmid, A. K. & Zaluzec, N. J.
Object Type: Report
System: The UNT Digital Library
INTERNATIONAL PROGRAM: SUMMARY REPORT ON THE PROPERTIES OF CEMENTITIOUS WASTE FORMS (open access)

INTERNATIONAL PROGRAM: SUMMARY REPORT ON THE PROPERTIES OF CEMENTITIOUS WASTE FORMS

This report provides a summary of the results on the properties of cementitious waste forms obtained as part of the International Program. In particular, this report focuses on the results of Task 4 of the Program that was initially entitled ''Improved Retention of Key Contaminants of Concern in Low Temperature Immobilized Waste Forms''. Task 4 was a joint program between Khlopin Radium Institute and the Savannah River National Laboratory. The task evolved during this period into a study of cementitious waste forms with an expanded scope that included heat of hydration and fate and transport modeling. This report provides the results for Task 4 of the International Program as of the end of FY06 at which time funding for Task 4 was discontinued due to the needs of higher priority tasks within the International Program. Consequently, some of the subtasks were only partially completed, but it was considered important to capture the results up to this point in time. Therefore, this report serves as the closeout report for Task 4. The degree of immobilization of Tc-99 within the Saltstone waste form was measured through monolithic and crushed grout leaching tests. An effective diffusion coefficient of 4.8 x 10{sup -12} (Leach …
Date: March 2, 2007
Creator: Harbour, J
Object Type: Report
System: The UNT Digital Library
Letter to Eduard Smetanin, Dated March 2, 2007: Final Crada Report. (open access)

Letter to Eduard Smetanin, Dated March 2, 2007: Final Crada Report.

The IPP/DOE program office has finished its evaluation of the alpha-emitting isotope work with Kurchatov Institute and IPPE, and they have made an important decision about the future of this work. IPP/DOE has directed us to re-program the work and add more funds, so the emphasis will be on production of Th228. By making this re-direction of the isotope work, IPPE will see several important benefits: (a) the payments will be made faster to IPPE by using the ISTC Agreement; (b) a larger amount of money will be paid to IPPE; and (c) a profitable future business opportunity for IPPE is more probable.
Date: March 2, 2007
Creator: Ehst, D. A.
Object Type: Report
System: The UNT Digital Library
A Multigroup diffusion Solver Using Pseudo Transient Continuation for a Radiaiton-Hydrodynamic Code with Patch-Based AMR (open access)

A Multigroup diffusion Solver Using Pseudo Transient Continuation for a Radiaiton-Hydrodynamic Code with Patch-Based AMR

We present a scheme to solve the nonlinear multigroup radiation diffusion (MGD) equations. The method is incorporated into a massively parallel, multidimensional, Eulerian radiation-hydrodynamic code with adaptive mesh refinement (AMR). The patch-based AMR algorithm refines in both space and time creating a hierarchy of levels, coarsest to finest. The physics modules are time-advanced using operator splitting. On each level, separate 'level-solve' packages advance the modules. Our multigroup level-solve adapts an implicit procedure which leads to a two-step iterative scheme that alternates between elliptic solves for each group with intra-cell group coupling. For robustness, we introduce pseudo transient continuation ({Psi}tc). We analyze the magnitude of the {Psi}tc parameter to ensure positivity of the resulting linear system, diagonal dominance and convergence of the two-step scheme. For AMR, a level defines a subdomain for refinement. For diffusive processes such as MGD, the refined level uses Dirichet boundary data at the coarse-fine interface and the data is derived from the coarse level solution. After advancing on the fine level, an additional procedure, the sync-solve (SS), is required in order to enforce conservation. The MGD SS reduces to an elliptic solve on a combined grid for a system of G equations, where G is the …
Date: March 2, 2007
Creator: Shestakov, A I & Offner, S R
Object Type: Article
System: The UNT Digital Library
RadTracker: Optical Imaging of High Energy Radiation Tracks (open access)

RadTracker: Optical Imaging of High Energy Radiation Tracks

This project examined the possibility of extending the recently demonstrated radoptic detection approach to gamma imaging. Model simulations of the light scattering process predicted that expected signal levels were small and likely below the detection limit of large area, room-temperature detectors. A series of experiments using pulsed x-ray excitation, modulated gamma excitation and optical pump-probe methods confirmed those theoretical predictions. At present the technique does not appear to provide a viable approach to volumetric radiation detection; however, in principal, orders of magnitude improvement in the SNR can result by using designer materials to concentrate and localize the radiation-absorption induced charge, simultaneously confining the optical mode to increase 'fill' factor and overlap of the probe beam with the affected regions, and employing high speed gated imaging detectors to measure the scattered signal.
Date: March 2, 2007
Creator: Vernon, S. P.; Lowry, M. E.; Comaskey, B. J.; Heebner, J. E.; Kallman, J. S. & Richards, J. B.
Object Type: Report
System: The UNT Digital Library
Analysis Procedures for Double-Shell Target Concentricity and Wall Thickness (open access)

Analysis Procedures for Double-Shell Target Concentricity and Wall Thickness

The LLNL Target Fabrication Team (TFT) asked the Center for Non-Destructive Characterization (CNDC) to use CNDC's KCAT or Xradia's Micro computed tomography (CT) system to collect three-dimensional (3D) tomographic data of a set of double-shell targets and determine, among other items, the following: (1) the concentricity of the outer surface of the inner shell with respect to the inner surface of the outer shell with an accuracy of 1-2 micrometers, and (2) the wall thickness uniformity of the outer shell with an accuracy of 1-2 micrometers. The CNDC used Xradia's Micro CT system to collect the data. Bill Brown performed the concentricity analysis, and John Sain performed the wall thickness uniformity analysis. Harry Martz provided theoretical guidance, and Dan Schneberk contributed technical (software) support. This document outlines the analysis procedures used in each case. The double-shell targets, as shown in Figures 1 and 2, consist of an inner shell (or capsule), a two-piece spherical aerogel intermediary shell, and a two-piece spherical outer shell. The three elements are designed and fabricated to be concentric--with the aerogel shell acting as a spacer between the inner shell and outer shell--with no to minimum air gaps in the final assembly. The outer diameters of …
Date: March 2, 2006
Creator: Sain, J D; Brown, W D; Martz, H E & Schneberk, D J
Object Type: Report
System: The UNT Digital Library
Bioremediation of Petroleum Hydrocarbons in Heterogeneous Soils (open access)

Bioremediation of Petroleum Hydrocarbons in Heterogeneous Soils

Western Research Institute (WRI) in conjunction with the University of Wyoming, Department of Renewable Resources and the U.S. Department of Energy, under Task 35, conducted a laboratory-scale study of hydrocarbon biodegradation rates versus a variety of physical and chemical parameters to develop a base model. By using this model, biodegradation of Petroleum hydrocarbons in heterogeneous soils can be predicted. The base model, as developed in this study, have been tested by both field and laboratory data. Temperature, pH, and nutrients appear to be the key parameters that can be incorporate into the model to predict biodegradation rates. Results to date show the effect of soil texture and source on the role of each parameter in the rates of hydrocarbon biodegradation. Derived from the existing study, an alternative approach of using CO{sub 2} accumulation data has been attempted by our collaborators at the University of Wyoming. The model has been modified and fine tuned by incorporating these data to provide more information on biodegradation.
Date: March 2, 2006
Creator: Jin, Song; Fallgren, Paul & Brown, Terry
Object Type: Report
System: The UNT Digital Library
Distinguishing between Dirac and Majorana neutrinos withtwo-particle interferometry (open access)

Distinguishing between Dirac and Majorana neutrinos withtwo-particle interferometry

Two-particle interferometry, a second-order interferenceeffect, is explored as another possible tool to distinguish betweenmassive Dirac and Majorana neutrinos. A simple theoretical framework isdiscussed in the context of several gedanken experiments. The method canin principle provide both the mass scale and the quantum nature of theneutrino for a certain class of incoherent left-handed sourcecurrents.
Date: March 2, 2006
Creator: Gutierrez, Thomas D.
Object Type: Article
System: The UNT Digital Library
Errors Associated with the Direct Measurement of Radionuclides in Wounds (open access)

Errors Associated with the Direct Measurement of Radionuclides in Wounds

Work in radiation areas can occasionally result in accidental wounds containing radioactive materials. When a wound is incurred within a radiological area, the presence of radioactivity in the wound needs to be confirmed to determine if additional remedial action needs to be taken. Commonly used radiation area monitoring equipment is poorly suited for measurement of radioactive material buried within the tissue of the wound. The Lawrence Livermore National Laboratory (LLNL) In Vivo Measurement Facility has constructed a portable wound counter that provides sufficient detection of radioactivity in wounds as shown in Fig. 1. The LLNL wound measurement system is specifically designed to measure low energy photons that are emitted from uranium and transuranium radionuclides. The portable wound counting system uses a 2.5cm diameter by 1mm thick NaI(Tl) detector. The detector is connected to a Canberra NaI InSpector{trademark}. The InSpector interfaces with an IBM ThinkPad laptop computer, which operates under Genie 2000 software. The wound counting system is maintained and used at the LLNL In Vivo Measurement Facility. The hardware is designed to be portable and is occasionally deployed to respond to the LLNL Health Services facility or local hospitals for examination of personnel that may have radioactive materials within a …
Date: March 2, 2006
Creator: Hickman, D. P.
Object Type: Report
System: The UNT Digital Library