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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.
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)
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
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
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
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
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
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
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
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
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
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
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
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
Bio-/Photo-Chemical Separation and Recovery of Uranium
Citric acid forms bidentate, tridentate, binuclear or polynuclear species with transition metals and actinides. Biodegradation of metal citrate complexes is influenced by the type of complex formed with metal ions. While bidentate complexes are readily biodegraded, tridentate, binuclear and polynuclear species are recalcitrant. Likewise certain transition metals and actinides are photochemically active in the presence of organic acids. Although the uranyl citrate complex is not biodegraded, in the presence of visible light it undergoes photochemical oxidation/reduction reactions which result in the precipitation of uranium as UO{sub 3} {center_dot} H{sub 2}O. Consequently, we developed a process where uranium is extracted from contaminated soils and wastes by citric acid. The citric-acid extract is subjected to biodegradation to recover the toxic metals, whereas uranyl citrate which is recalcitrant remains in solution. Photochemical degradation of the uranium citrate complex resulted in the precipitation of uranium. Thus the toxic metals and uranium in mixed waste are recovered in separate fractions for recycling or for disposal. The use of naturally-occurring compounds and the combined chemical and microbiological treatment process is more efficient than present methods and should result in considerable savings in cost.
Date:
March 12, 2008
Creator:
Francis, A. J. & Dodge, C. J.
Object Type:
Article
System:
The UNT Digital Library
The ADESORB Process for Economical Production of Sorbents for Mercury Removal from Coal Fired Power Plants
The DOE's National Energy Technology Laboratory (NETL) currently manages the largest research program in the country for controlling coal-based mercury emissions. NETL has shown through various field test programs that the determination of cost-effective mercury control strategies is complex and highly coal- and plant-specific. However, one particular technology has the potential for widespread application: the injection of activated carbon upstream of either an electrostatic precipitator (ESP) or a fabric filter baghouse. This technology has potential application to the control of mercury emissions on all coal-fired power plants, even those with wet and dry scrubbers. This is a low capital cost technology in which the largest cost element is the cost of sorbents. Therefore, the obvious solutions for reducing the costs of mercury control must focus on either reducing the amount of sorbent needed or decreasing the cost of sorbent production. NETL has researched the economics and performance of novel sorbents and determined that there are alternatives to the commercial standard (NORIT DARCO{reg_sign} Hg) and that this is an area where significant technical improvements can still be made. In addition, a key barrier to the application of sorbent injection technology to the power industry is the availability of activated carbon production. …
Date:
March 12, 2008
Creator:
Stewart, Robin
Object Type:
Report
System:
The UNT Digital Library
Oxidation and combustion of the n-hexene isomers: a wide range kinetic modeling study
A detailed chemical kinetic mechanism has been developed to study the oxidation of the straight-chain isomers of hexene over a wide range of operating conditions. The main features of this detailed kinetic mechanism, which includes both high and low temperature reaction pathways, are presented and discussed with special emphasis on the main classes of reactions involved in alkene oxidation. Simulation results have been compared with experimental data over a wide range of operating conditions including shock tube, jet stirred reactor and rapid compression machine. The different reactivities of the three isomers have been successfully predicted by the model. Isomerization reactions of the hexenyl radicals were found to play a significant role in the chemistry and interactions of the three n-hexene isomers. A comparative reaction flux analysis is used to verify and discuss the fundamental role of the double bond position in the isomerization reactions of alkenyl radicals, as well as the impact of the allylic site in the low and high temperature mechanism of fuel oxidation.
Date:
March 12, 2008
Creator:
Mehl, M; Vanhove, G; Pitz, W J & Ranzi, E
Object Type:
Article
System:
The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 39, No. 66, Ed. 1 Wednesday, March 12, 2008
Free weekly newspaper that includes business and classified advertising.
Date:
March 12, 2008
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 40, No. 68, Ed. 1 Thursday, March 12, 2009
Free weekly newspaper that includes business and classified advertising.
Date:
March 12, 2009
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
Port Aransas South Jetty (Port Aransas, Tex.), Vol. 39, No. 11, Ed. 1 Thursday, March 12, 2009
Weekly newspaper from Port Aransas, Texas on Mustang Island that includes local, state and national news along with extensive advertising.
Date:
March 12, 2009
Creator:
Judson, Mary Henkel
Object Type:
Newspaper
System:
The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 40, No. 69, Ed. 1 Thursday, March 12, 2009
Free weekly newspaper that includes business and classified advertising.
Date:
March 12, 2009
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
Comprehensive Nuclear-Test-Ban Treaty: Issues and Arguments
This report discusses the Comprehensive Nuclear-Test-Ban Treaty that would ban all nuclear explosions. The report presents a detailed, comprehensive discussion of the treaty's pros and cons from a U.S. perspective.
Date:
March 12, 2008
Creator:
Medalia, Jonathan
Object Type:
Report
System:
The UNT Digital Library
Cherokeean/Herald (Rusk, Tex.), Vol. 154, No. 3, Ed. 1 Wednesday, March 12, 2003
Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date:
March 12, 2003
Creator:
Whitehead, Marie
Object Type:
Newspaper
System:
The Portal to Texas History
Cherokeean Herald (Rusk, Tex.), Vol. 159, No. 3, Ed. 1 Wednesday, March 12, 2008
Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date:
March 12, 2008
Creator:
Whitehead, Marie
Object Type:
Newspaper
System:
The Portal to Texas History