Novel, convenient, and nonpersistent radiotracer for environmental and energy applications (open access)

Novel, convenient, and nonpersistent radiotracer for environmental and energy applications

A newly-available radioisotopic system, /sup 172/Hf-/sup 172/Lu, has excellent potential for tracer applications in which nuclear data acquisition must be accomplished in real time. The 6.7-day half-life of /sup 172/Lu is sufficient for a large fraction of tracer experiments, and should allow the direct incorporation of /sup 172/Lu into tests that have traditionally utilized much longer-lived radionuclides. Since /sup 172/Lu is the daughter component of a radioisotope generator, however, its effective shelf-life is determined by the half-life of its 1.9-year /sup 172/Hf parent. Consequently, the frequency of isotope procurement need not be any more extensive than investigators would normally be accustomed to. Discussion relevant to isotope production, generator operation, and nuclide acquisition is presented in this paper.
Date: March 12, 1984
Creator: Grant, P.M.
Object Type: Article
System: The UNT Digital Library
(Investigation of low-cost solar cells based on Cu/sub 2/O). Third quarterly progress report, November 1, 1979-January 31, 1980 (open access)

(Investigation of low-cost solar cells based on Cu/sub 2/O). Third quarterly progress report, November 1, 1979-January 31, 1980

Efforts this quarter concentrated on completion and check-out of the MBE system, deposition of ZnS films, analysis of the internal photoresponse for Cu-Cu/sub 2/O cells, and fabrication and characterization of Cu-Cu/sub 2/O solar cells. In-doped ZnS films with very good optical quality and finite conductivity were obtained by co-depositing In and ZnS. Analysis of the internal photoresponse indicated that minority carrier diffusion lengths on the order of 10 ..mu..m are being achieved with the present Cu/sub 2/O growth procedure. Active area values of J/sub PH/ = 8.52 mA/cm/sup 2/ and AM1 Efficiency = 1.76% were achieved for Cu-Cu/sub 2/O cells. These devices appear to have an MIS structure, or fixed charge at the interface. In particular, analysis of I-V data indicates that the current-voltage characteristics for applied voltages greater than 0.3 V are characterized by n approx. = 1 and J/sub 0/ approx. = 2 x 10/sup -9/ mA/cm/sup 2/, which implies an effective barrier height of 0.94 eV compared to the theoretical value of 0.7 eV for a Cu/Cu/sub 2/O Schottky barrier. Another very significant achievement this past quarter was the development of a surface preparation procedure which results in a nearly perfect stochiometry at the surface.
Date: March 12, 1980
Creator: Olsen, L. C.
Object Type: Report
System: The UNT Digital Library
At-sea test validation data needed to verify the NOAA/DOE CWP Analytic Code (open access)

At-sea test validation data needed to verify the NOAA/DOE CWP Analytic Code

Test data requirements are developed in this memorandum for the one-third scale Ocean Thermal Energy Conversion (OTEC) cold water pipe (CWP) at-sea tests. A major goal of the at-sea tests is to collect sufficient data so that the National Oceanic and Atmospheric Administration (NOAA)/Department of Energy (DOE) CWP Analytic Code can be validated. The code is examined to determine the individual responses requiring verification. The wave environment is then considered for prototype survival and the scaled test. The expected response of the OTEC CWP test article in the test environment is used to form a basis of the test plan. Requirements for the tests of standard configurations of the OTEC CWP test system are first planned followed by requirements for tests of alternate configurations and evolutions. The final product is a set of justified NOAA/CWP analytic code validation requirements.
Date: March 12, 1980
Creator: Major, R. A.
Object Type: Report
System: The UNT Digital Library
Massachusetts State Briefing Book for low-level radioactive waste management (open access)

Massachusetts State Briefing Book for low-level radioactive waste management

The Massachusetts State Briefing Book is one of a series of State briefing books on low-level radioactive waste management practices. It has been prepared to assist State and Federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Massachusetts. The profile is the result of a survey of NRC licensees in Massachusetts. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may impact waste management practices in Massachusetts.
Date: March 12, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
ZONE - a finite element mesh generator. [2-D, for CDC 7600] (open access)

ZONE - a finite element mesh generator. [2-D, for CDC 7600]

The ZONE computer program is a finite element mesh generator that produces the nodes and element description of any two-dimensional geometry. The geometry is subdivided into a mesh of quadrilateral and triangular zones arranged sequentially in an ordered march through the geometry. The order of march can be chosen so that the minimum bandwidth is obtained. The node points are defined in terms of the x and y coordinates in a global rectangular coordinate system. The zones generated are quadrilaterals or triangles defined by four node points in a counterclockwise sequence. Node points defining the outside boundary are generated for slide lines and to describe pressure boundary conditions. The mesh that is generated can be used as input to any two dimensional as well as any axisymmetrical structure program. The following points are taken up: program concept and characteristics; regions; layers; meridians (offset, circular arc, ellipse); rays; common characterstics - rays and meridians, ZONE input description; output files; examples; and program availability. Also generated is the input to the program PLOT. 15 figures. (RWR)
Date: March 12, 1980
Creator: Burger, M.J.
Object Type: Report
System: The UNT Digital Library
Oxidation of alloys targeted for advanced steam turbines (open access)

Oxidation of alloys targeted for advanced steam turbines

Ultra supercritical (USC) power plants offer the promise of higher efficiencies and lower emissions. Current goals of the U.S. Department of Energy’s Advanced Power Systems Initiatives include coal generation at 60% efficiency, which would require steam temperatures of up to 760°C. This research examines the steamside oxidation of alloys for use in USC systems, with emphasis placed on applications in high- and intermediate-pressure turbines.
Date: March 12, 2006
Creator: Holcomb, G. R.; Covino, B. S., Jr.; Bullard, S. J.; Ziomek-Moroz, M. & Alman, D. E.
Object Type: Article
System: The UNT Digital Library
Final Report DE-FG02-97ER62475 (open access)

Final Report DE-FG02-97ER62475

This project began with the simple goal of trying to understand the diversity of dissimilatory metal-reducing microorganisms that might be found in subsurface environments. It ended with a sophisticated understanding not only of what microorganisms are important for metal reduction in uranium-contaminated subsurface environments, but also their physiological status during in situ uranium bioremediation. These findings have provided unprecedented insight into uranium bioremediation and the methods by which this process might be optimized. A brief summary of the major accomplishments of the project is given.
Date: March 12, 2008
Creator: Lovley, Derek, R.
Object Type: Report
System: The UNT Digital Library
Ferromagnetism and suppression of metallic clusters in Fe implanted ZnO -- a phenomenon related to defects? (open access)

Ferromagnetism and suppression of metallic clusters in Fe implanted ZnO -- a phenomenon related to defects?

We investigated ZnO(0001) single crystals annealed in high vacuum with respect to their magnetic properties and cluster formation tendency after implant-doping with Fe. While metallic Fe cluster formation is suppressed, no evidence for the relevance of the Fe magnetic moment to the observed ferromagnetism was found. The latter along with the cluster suppression is discussed with respect to defects in the ZnO host matrix, since the crystalline quality of the substrates was lowered due to the preparation as observed by x-ray diffraction.
Date: March 12, 2008
Creator: Arenholz, Elke; Zhou, S.; Potzger, K.; Talut, G.; Reuther, H.; Kuepper, K. et al.
Object Type: Article
System: The UNT Digital Library
Simulation and Analysis of Microwave Transmission through an Electron Cloud, a Comparison of Results (open access)

Simulation and Analysis of Microwave Transmission through an Electron Cloud, a Comparison of Results

Simulation studies for transmission of microwaves through electron cloudes show good agreement with analytic results. The elctron cloud produces a shift in phase of the microwave. Experimental observation of this phenomena would lead to a useful diagnostic tool for acessing the local density of electron clouds in an accelerator. These experiments are being carried out at the CERN SPS and the PEP-II LER at SLAC and is proposed to be done at the Fermilab maininjector. In this study, a brief analysis of the phase shift is provided and the results are compared with that obtained from simulations.
Date: March 12, 2007
Creator: Sonnad, Kiran; Sonnad, Kiran; Furman, Miguel; Veitzer, Seth; Stoltz, Peter & Cary, John
Object Type: Article
System: The UNT Digital Library
The Columbia River Protection Supplemental Technologies Quality Assurance Project Plan (open access)

The Columbia River Protection Supplemental Technologies Quality Assurance Project Plan

Pacific Northwest National Laboratory researchers are working on the Columbia River Protection Supplemental Technologies Project. This project is a U. S. Department of Energy, Office of Environmental Management-funded initiative designed to develop new methods, strategies, and technologies for characterizing, modeling, remediating, and monitoring soils and groundwater contaminated with metals, radionuclides, and chlorinated organics. This Quality Assurance Project Plan provides the quality assurance requirements and processes that will be followed by the Technologies Project staff.
Date: March 12, 2008
Creator: Fix, N. J.
Object Type: Report
System: The UNT Digital Library
Physics division annual report 2005. (open access)

Physics division annual report 2005.

This report highlights the research performed in 2005 in the Physics Division of Argonne National Laboratory. The Division's programs include operation of ATLAS as a national user facility, nuclear structure and reaction research, nuclear theory, medium energy nuclear research and accelerator research and development. The mission of Nuclear Physics is to understand the origin, evolution and structure of baryonic matter in the universe--the matter that makes up stars, planets and human life itself. The Division's research focuses on innovative new ways to address this mission and 2005 was a year of great progress. One of the most exciting developments is the initiation of the Californium Rare Ion Breeder Upgrade, CARIBU. By combining a Cf-252 fission source, the gas catcher technology developed for rare isotope beams, a high-resolution isobar separator, and charge breeding ECR technology, CARIBU will make hundreds of new neutron-rich isotope beams available for research. The cover illustration shows the anticipated intensities of low-energy beams that become available for low-energy experiments and for injection into ATLAS for reacceleration. CARIBU will be completed in early 2009 and provide us with considerable experience in many of the technologies developed for a future high intensity exotic beam facility. Notable results in research …
Date: March 12, 2007
Creator: Glover, J. & Physics
Object Type: Report
System: The UNT Digital Library
The Nature of the Dissociation Sites of Hydrogen Molecules on Ru(001) (open access)

The Nature of the Dissociation Sites of Hydrogen Molecules on Ru(001)

Scanning tunneling microscopy (STM) was used to study the dissociative adsorption of H{sub 2} on Ru(001) near saturation coverage, when the number of residual hydrogen vacancies (i.e., unoccupied Ru sites) is small. We found that H{sub 2} dissociation takes place only on Ru sites where the metal atom is not bound to any H atom. Such active sites are formed when at least 3 H-vacancies aggregate by thermal diffusion. Sites formed by single H-vacancies or pairs of adjoining vacancies were found to be unreactive toward H{sub 2}. As a similar phenomenon was found previously on Pd(111), the present results indicate that the active sites for H2 dissociation share a common characteristic among catalytically active transition metals.
Date: March 12, 2008
Creator: Salmeron, Miquel; Rose, Franck; Tartakhanov, Mous; Fomin, Evgeni & Salmeron, Miquel
Object Type: Article
System: The UNT Digital Library
The Two-Loop Six-Point MHV Amplitude in Maximally Supersymmetric Yang-Mills Theory (open access)

The Two-Loop Six-Point MHV Amplitude in Maximally Supersymmetric Yang-Mills Theory

We give a representation of the parity-even part of the planar two-loop six-gluon MHV amplitude of N = 4 super-Yang-Mills theory, in terms of loop-momentum integrals with simple dual conformal properties. We evaluate the integrals numerically in order to test directly the ABDK/BDS all-loop ansatz for planar MHV amplitudes. We find that the ansatz requires an additive remainder function, in accord with previous indications from strong-coupling and Regge limits. The planar six-gluon amplitude can also be compared with the hexagonal Wilson loop computed by Drummond, Henn, Korchemsky and Sokatchev in arXiv:0803.1466 [hep-th]. After accounting for differing singularities and other constants independent of the kinematics, we find that the Wilson loop and MHV-amplitude remainders are identical, to within our numerical precision. This result provides non-trivial confirmation of a proposed n-point equivalence between Wilson loops and planar MHV amplitudes, and suggests that an additional mechanism besides dual conformal symmetry fixes their form at six points and beyond.
Date: March 12, 2008
Creator: Bern, Z.; Dixon, L.J.; Kosower, D.A.; Roiban, R.; Spradlin, M.; Vergu, C. et al.
Object Type: Article
System: The UNT Digital Library
Hawaii Geothermal Project Environmental Impact Statement Scoping Meetings. Volume 5 (open access)

Hawaii Geothermal Project Environmental Impact Statement Scoping Meetings. Volume 5

None
Date: March 12, 1992
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Laboratory Directed Research and Development Program FY 2007 (open access)

Laboratory Directed Research and Development Program FY 2007

Report on Ernest Orlando Lawrence Berkeley National Laboratory Laboratory Directed Research and Development Program FY 2007
Date: March 12, 2008
Creator: Hansen, Todd C. & Lawrence, Ernest Orlando
Object Type: Report
System: The UNT Digital Library
Standard and Unconventional Experiments in Lepton Physics (open access)

Standard and Unconventional Experiments in Lepton Physics

None
Date: March 12, 2008
Creator: Perl, Martin L.
Object Type: Article
System: The UNT Digital Library
Chemical Speciation of Sulfur in Marine Cloud Droplets and Particles: Analysis of Individual Particles from Marine Boundary Layer over the California Current (open access)

Chemical Speciation of Sulfur in Marine Cloud Droplets and Particles: Analysis of Individual Particles from Marine Boundary Layer over the California Current

Detailed chemical speciation of the dry residue particles from individual cloud droplets and interstitial aerosol collected during the Marine Stratus Experiment (MASE) was performed using a combination of complementary microanalysis techniques. Techniques include computer controlled scanning electron microscopy with energy dispersed analysis of X-rays (CCSEM/EDX), time-of-flight secondary ionization mass spectrometry (TOF-SIMS), and scanning transmission X-ray microscopy with near edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS). Samples were collected at the ground site located in Point Reyes National Seashore, approximately 1 km from the coast. This manuscript focuses on the analysis of individual particles sampled from air masses that originated over the open ocean and then passed through the area of the California current located along the northern California coast. Based on composition, morphology, and chemical bonding information, two externally mixed, distinct classes of sulfur containing particles were identified: chemically modified (aged) sea salt particles and secondary formed sulfate particles. The results indicate substantial heterogeneous replacement of chloride by methanesulfonate (CH3SO3-) and non-sea salt sulfate (nss-SO42-) in sea-salt particles with characteristic ratios of nss-S/Na>0.10 and CH3SO3-/nss-SO42->0.6.
Date: March 12, 2008
Creator: William R. Wiley Environmental Sciences Laboratory, Pacific Northwest National Laboratory; Gilles, Mary K; Hopkins, Rebecca J.; Desyaterik, Yury; Tivanski, Alexei V.; Zaveri, Rahul A. et al.
Object Type: Article
System: The UNT Digital Library
Environmental Tests of the Flight GLAST LAT Tracker Towers (open access)

Environmental Tests of the Flight GLAST LAT Tracker Towers

The Gamma-ray Large Area Space telescope (GLAST) is a gamma-ray satellite scheduled for launch in 2008. Before the assembly of the Tracker subsystem of the Large Area Telescope (LAT) science instrument of GLAST, every component (tray) and module (tower) has been subjected to extensive ground testing required to ensure successful launch and on-orbit operation. This paper describes the sequence and results of the environmental tests performed on an engineering model and all the flight hardware of the GLAST LAT Tracker. Environmental tests include vibration testing, thermal cycles and thermal-vacuum cycles of every tray and tower as well as the verification of their electrical performance.
Date: March 12, 2008
Creator: Bagagli, R.; Baldini, L.; Bellazzini, R.; Barbiellini, G.; Belli, F.; Borden, T. et al.
Object Type: Article
System: The UNT Digital Library
Benefits of IEEE-754 features in modern symmetric tridiagonaleigensolvers (open access)

Benefits of IEEE-754 features in modern symmetric tridiagonaleigensolvers

Bisection is one of the most common methods used to compute the eigenvalues of symmetric tridiagonal matrices. Bisection relies on the Sturm count: For a given shift a, the number of negative pivots in the factorization T - {sigma}I = LDL{sup T} equals the number of eigenvalues of T that are smaller than a. In IEEE-754 arithmetic, the value oo permits the computation to continue past a zero pivot, producing a correct Sturm count when T is unreduced. Demmel and Li showed that using oo rather than testing for zero pivots within the loop could significantly improve performance on certain architectures. When eigenvalues are to be computed to high relative accuracy, it is often preferable to work with LDL{sup T} factorizations instead of the original tridiagonal T. One important example is the MRRR algorithm. When bisection is applied to the factored matrix, the Sturm count is computed from LDL{sup T} which makes differential stationary and progressive qds algorithms the methods of choice. While it seems trivial to replace T by LDL{sup T}, in reality these algorithms are more complicated: In IEEE-754 arithmetic, a zero pivot produces an overflow followed by an invalid exception (NaN, or 'Not a Number') that renders …
Date: March 12, 2006
Creator: Marques, Osni; Riedy, Jason E. & Vomel, Christof
Object Type: Article
System: The UNT Digital Library
Final Report DE-FG02-04ER63719 (open access)

Final Report DE-FG02-04ER63719

The studies completed under this grant significantly advanced the understanding and design of strategies for in situ uranium bioremediation. Novel strategies identified show promise to make in situ uranium bioremediation technically simpler and less expensive. As detailed, important findings included: (1) Development of an electron donor delivery strategy to prolong the in situ activity of Geobacter species and enhance the removal of uranium from the groundwater; (2) Demonstration that reproducible year-to-year field experiments were possible at the ERSP study site in Rifle, CO, making hypothesis-driven field experimentation possible; (3) Elucidation of the geochemical and microbiological heterogeneities with the subsurface during in situ uranium bioremediation, which must be accounted for to accurately model the bioremediation process; (4) The discovery that most of the U(VI) contamination at the Rifle site is sediment-associated rather than mobile in the groundwater, as previously considered; (5) The finding that unlike soluble U(VI), sediment-associated U(VI) is not microbially reducible; (6) The demonstration that electrodes may be an effective alternative to acetate as an electron donor to promote microbial U(VI) reduction in the subsurface with the added benefit that electrode-promoted microbial U(VI) reduction offers the possibility of removing the immobilized uranium from the subsurface; and (7) The finding …
Date: March 12, 2008
Creator: Lovley, Derek, R.
Object Type: Report
System: The UNT Digital Library
Data Overview for Sensor Fish Samples Acquired at Ice Harbor, John Day, and Bonneville II Dams in 2005, 2006, and 2007 (open access)

Data Overview for Sensor Fish Samples Acquired at Ice Harbor, John Day, and Bonneville II Dams in 2005, 2006, and 2007

The purpose of this work was to acquire Sensor Fish data on turbine passage at Bonneville II, John Day, and Ice Harbor dams for later analysis and use. The original data sets have been entered into a database and are being maintained by Pacific Northwest National Laboratory pending delivery to the U.S. Army Corps of Engineers when requested. This report provides documentation for the data sets acquired and details about the operations of the Sensor Fish and interpretation of Sensor Fish data that will be necessary for later use of the acquired data. A limited review of the acquired data was conducted to assess its quality and to extract information that might prove useful to its later use.
Date: March 12, 2008
Creator: Carlson, Thomas J.; Duncan, Joanne P. & Deng, Zhiqun
Object Type: Report
System: The UNT Digital Library
Waste Isolation Pilot Plant Environmental Monitoring Plan (open access)

Waste Isolation Pilot Plant Environmental Monitoring Plan

U.S. Department of Energy (DOE) Order 450.1, Environmental Protection Program, requires each DOE site to conduct environmental monitoring. Environmental monitoring at the Waste Isolation Pilot Plant (WIPP) is conducted in order to: (a) Verify and support compliance with applicable federal, state, and local environmental laws, regulations, permits, and orders; (b) Establish baselines and characterize trends in the physical, chemical, and biological condition of effluent and environmental media; (c) Identify potential environmental problems and evaluate the need for remedial actions or measures to mitigate the problems; (d) Detect, characterize, and report unplanned releases; (e) Evaluate the effectiveness of effluent treatment and control, and pollution abatement programs; and (f) Determine compliance with commitments made in environmental impact statements, environmental assessments, safety analysis reports, or other official DOE documents. This Environmental Monitoring Plan (EMP) explains the rationale and design criteria for the environmental monitoring program, extent and frequency of monitoring and measurements, procedures for laboratory analyses, quality assurance (QA) requirements, program implementation procedures, and direction for the preparation and disposition of reports. Changes to the environmental monitoring program may be necessary to allow the use of advanced technology and new data collection techniques. This EMP will document changes in the environmental monitoring program. …
Date: March 12, 2008
Creator: Washington Regulatory and Environmental Services
Object Type: Report
System: The UNT Digital Library
FRACTURE ENHANCED SOIL VAPOR EXTRACTION TECHNOLOGY DEMONSTRATION AT THE A-014 OUTFALL (open access)

FRACTURE ENHANCED SOIL VAPOR EXTRACTION TECHNOLOGY DEMONSTRATION AT THE A-014 OUTFALL

Data collected during this study show that the performance of hydraulically fractured wells (with respect to mass removal rates) may tend to decrease with time following precipitation events. These effects are due to temporary increases in water saturation in the formation within the vicinity of the fractures, therefore, the wells should tend to rebound during subsequent dry periods. The data available for fractured well versus conventional well performance (with respect to flow rate versus vacuum pressure) are limited in this study. However, the data that we have to draw from suggest that, with the possible exception of a few extreme examples, hydraulically fractured wells tend to perform better than conventional wells during soil vapor extraction (SVE) operation at the A-14 Outfall. The pancake like geometry associated with hydraulic fractures also leads to a significant increase in zone of influence (ZOI), as compared to conventional wells. The increase in ZOI is due to the radially extending, horizontal, high-permeability conduit nature of the hydraulic fracture, however, air-flow into the fracture is predominately vertical (occurring at right angles to the fracture plane). Flow rates from above and below the fracture will tend to be equivalent when the formation is homogeneous, however, in the …
Date: March 12, 2008
Creator: Riha, B; Warren Hyde, W & Richard Hall (NOEMAIL), R
Object Type: Report
System: The UNT Digital Library
Ambient pressure photoelectron spectroscopy: a new tool for surface science and nanotechnology (open access)

Ambient pressure photoelectron spectroscopy: a new tool for surface science and nanotechnology

Progress in science often follows or parallels the development of new techniques. The optical microscope helped convert medicine and biology from a speculative activity in old times to today's sophisticated scientific disciplines. The telescope changed the study and interpretation of heavens from mythology to science. X-ray diffraction enabled the flourishing of solid state physics and materials science. The technique object of this review, Ambient Pressure Photoelectron Spectroscopy or APPES for short, has also the potential of producing dramatic changes in the study of liquid and solid surfaces, particularly in areas such as atmospheric, environment and catalysis sciences. APPES adds an important missing element to the host of techniques that give fundamental information, i.e., spectroscopy and microscopy, about surfaces in the presence of gases and vapors, as encountered in industrial catalysis and atmospheric environments. APPES brings electron spectroscopy into the realm of techniques that can be used in practical environments. Decades of surface science in ultra high vacuum (UHV) has shown the power of electron spectroscopy in its various manifestations. Their unique property is the extremely short elastic mean free path of electrons as they travel through condensed matter, of the order of a few atomic distances in the energy range …
Date: March 12, 2008
Creator: Salmeron, Miquel; Salmeron, Miquel & Schlogl, Robert
Object Type: Article
System: The UNT Digital Library