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Remaining Sites Verification Package for the 116-F-16, PNL Outfall and the 100-F-43, PNL Outfall Spillway, Waste Site Reclassification Form 2006-046
The 100-F-43 waste site is the portion of the former discharge spillway for the PNL Outfall formerly existing above the ordinary high water mark of the Columbia River. The spillway consisted of a concrete flume used to discharge waste effluents from the 100-F Experimental Animal Farm. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date:
September 14, 2006
Creator:
Dittmer, L. M.
Object Type:
Report
System:
The UNT Digital Library
Production of Gratings for High-Energy Petawatt-Class Lasers
At the time of this writing, we have manufactured and delivered more than 25 multilayer dielectric diffraction gratings from 470-800 mm in long aperture for pulse compression on Petawatt-class,1-micron laser systems being built at government and university facilities in the U.S and elsewhere. We present statistics of diffraction efficiency and its spatial uniformity, diffracted wavefront, and laser damage results on witness gratings. We also discuss yield, failure modes, and manufacturing improvements necessary to improve upon the current state of the art.
Date:
June 14, 2006
Creator:
Nguyen, H. T.; Carlson, T. C.; Hoaglan, C. R.; Nissen, J. D.; Aasen, M. D.; Peterson, J. E. et al.
Object Type:
Article
System:
The UNT Digital Library
A Coupled Model for Natural Convection and Condensation in HeatedSubsurface Enclosures Embedded in Fractured Rock
In heated tunnels such as those designated for emplacementof radioactive waste at Yucca Mountain, axial temperature gradients maycause natural convection processes that can significantly influence themoisture conditions in the tunnels and in the surrounding fractured rock.Large-scale convection cells would provide an effective mechanism foraxial vapor transport, driving moisture out of the formation away fromthe heated tunnel section into cool end sections (where no waste isemplaced). To study such processes, we have developed and applied anenhanced version of TOUGH2 (Pruess et al., 1999) adding a new module thatsolves for natural convection in open cavities. The new TOUGH2 simulatorsimultaneously handles (1) the flow and energy transport processes in thefractured rock; (2) the flow and energy transport processes in thecavity; and (3) the heat and mass exchange at the rock-cavity interface.The new module is applied to simulate the future thermal-hydrological(TH) conditions within and near a representative waste emplacement tunnelat Yucca Mountain. Particular focus is on the potential for condensationalong the emplacement section, a possible result of heat outputdifferences between individual waste packages.
Date:
April 14, 2006
Creator:
Halecky, N.; Birkholzer, J. T.; Webb, S. W.; Peterson, P. F. & Bodvarsson, G. S.
Object Type:
Article
System:
The UNT Digital Library
Germanium: From Its Discovery to SiGe Devices
Germanium, element No.32, was discovered in 1886 by Clemens Winkler. Its first broad application was in the form of point contact Schottky diodes for radar reception during WWII. The addition of a closely spaced second contact led to the first all-solid-state electronic amplifier device, the transistor. The relatively low bandgap, the lack of a stable oxide and large surface state densities relegated germanium to the number 2 position behind silicon. The discovery of the lithium drift process, which made possible the formation of p-i-n diodes with fully depletable i-regions several centimeters thick, led germanium to new prominence as the premier gamma-ray detector. The development of ultra-pure germanium yielded highly stable detectors which have remained unsurpassed in their performance. New acceptors and donors were discovered and the electrically active role of hydrogen was clearly established several years before similar findings in silicon. Lightly doped germanium has found applications as far infrared detectors and heavily Neutron Transmutation Doped (NTD) germanium is used in thermistor devices operating at a few milliKelvin. Recently germanium has been rediscovered by the silicon device community because of its superior electron and hole mobility and its ability to induce strains when alloyed with silicon. Germanium is again a …
Date:
June 14, 2006
Creator:
Haller, E.E.
Object Type:
Article
System:
The UNT Digital Library
A Probabilistic Approach to Classifying Supernovae UsingPhotometric Information
This paper presents a novel method for determining the probability that a supernova candidate belongs to a known supernova type (such as Ia, Ibc, IIL, etc.), using its photometric information alone. It is validated with Monte Carlo, and both space- and ground-based data. We examine the application of the method to well-sampled as well as poorly sampled supernova light curves and investigate to what extent the best currently available supernova models can be used for typing supernova candidates. Central to the method is the assumption that a supernova candidate belongs to a group of objects that can be modeled; we therefore discuss possible ways of removing anomalous or less well understood events from the sample. This method is particularly advantageous for analyses where the purity of the supernova sample is of the essence, or for those where it is important to know the number of the supernova candidates of a certain type (e.g., in supernova rate studies).
Date:
December 14, 2006
Creator:
Kuznetsova, Natalia V. & Connolly, Brian M.
Object Type:
Article
System:
The UNT Digital Library
SQUID-Detected Magnetic Resonance Imaging in MicroteslaFields
Magnetic resonance imaging (MRI) has developed into a powerful clinical tool for imaging the human body (1). This technique is based on nuclear magnetic resonance (NMR) of protons (2, 3) in a static magnetic field B{sub 0}. An applied radiofrequency pulse causes the protons to precess about B{sub 0} at their Larmor frequency {nu}{sub 0} = ({gamma}/2{pi})B{sub 0}, where {gamma} is the gyromagnetic ratio; {gamma}/2{pi} = 42.58 MHz/tesla. The precessing protons generate an oscillating magnetic field and hence a voltage in a nearby coil that is amplified and recorded. The application of three-dimensional magnetic field gradients specifies a unique magnetic field and thus an NMR frequency in each voxel of the subject, so that with appropriate encoding of the signals one can acquire a complete image (4). Most clinical MRI systems involve magnetic fields generated by superconducting magnets, and the current trend is to higher magnetic fields than the widely used 1.5-T systems (5). Nonetheless, there is ongoing interest in the development of less expensive imagers operating at lower fields. Commercially available 0.2-T systems based on permanent magnets offer both lower cost and a more open access than their higher-field counterparts, at the expense of signal-to-noise-ratio (SNR) and spatial resolution. …
Date:
August 14, 2006
Creator:
Moessle, Michael; Hatridge, Michael & Clarke, John
Object Type:
Article
System:
The UNT Digital Library
Holographic optical elements for the extreme-ultravioletregime
As the development of extreme ultraviolet (EUV) lithography progresses, interest grows in the extension of traditional optical components to the EUV regime. The strong absorption of EUV by most materials and its extremely short wavelength, however, makes it very difficult to implement many components that are commonplace in the longer wavelength regimes. One such component is the diffractive optical element used, for example, in illumination systems to efficiently generate modified pupil fills. Here we demonstrate the fabrication and characterization of EUV binary phase-only computer-generated holograms allowing arbitrary far-field diffraction patterns to be generated.
Date:
August 14, 2006
Creator:
Naulleau, Patrick P.; Salmassi, Farhad; Gullikson, Eric M. & Anderson, Erik H.
Object Type:
Article
System:
The UNT Digital Library
Remaining Sites Verification Package for the 1607-F5 Sanitary Sewer System (124-F-5), Waste Site Reclassification Form 2006-043
The 1607-F5 waste site is a former septic tank, tile field, and associated pipeline located within the 100-FR-1 Operable Unit that received sewage from the former 181-F Pumphouse. Lead, gamma-chlordane, and heptachlor epoxide were identified within or around the septic system at concentrations exceeding the direct exposure cleanup criteria. Multiple metal and pesticide constituents were also identified as exceeding the groundwater and river protection cleanup criteria. The results of verification sampling demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also showed that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date:
September 14, 2006
Creator:
Dittmer, L. M.
Object Type:
Report
System:
The UNT Digital Library
Onset of Convection in Two Liquid Layers with Phase Change
We perform linear stability calculations for horizontal fluid bilayers that can undergo a phase transformation, taking into account both buoyancy effects and thermocapillary effects in the presence of a vertical temperature gradient. We compare the familiar case of the stability of two immiscible fluids in a bilayer geometry with the less-studied case that the two fluids represent different phases of a single-component material, e.g., the water-steam system. The two cases differ in their interfacial boundary conditions: the condition that the interface is a material surface is replaced by the continuity of mass flux across the interface, together with an assumption of thermodynamic equilibrium that in the linearized equations represents the Clausius-Clapeyron relation relating the interfacial temperature and pressures. For the two-phase case, we find that the entropy difference between the phases plays a crucial role in determining the stability of the system. For small values of the entropy difference between the phases, the two-phase system can be linearly unstable to either heating from above or below. The instability is due to the Marangoni effect in combination with the effects of buoyancy (for heating from below). For larger values of the entropy difference the two-phase system is unstable only for heating …
Date:
September 14, 2006
Creator:
McFadden, G B; Coriell, S R; Gurski, K F & Cotrell, D L
Object Type:
Article
System:
The UNT Digital Library
A Strong-Lens Survey in AEGIS: the Influence of Large Scale Structure
We report on the results of a visual search for galaxy-scale strong gravitational lenses over 650 arcmin2 of HST/ACS imaging in the Extended Groth Strip (EGS). These deep F606W- and F814W-band observations are in the DEEP2-EGS field. In addition to a previously-known Einstein Cross also found by our search (the ''Cross'', HSTJ141735+52264, with z{sub lens} = 0.8106 and a published z{sub source} = 3.40), we identify two new strong galaxy-galaxy lenses with multiple extended arcs. The first, HSTJ141820+52361 (the ''Dewdrop''; z{sub lens} = 0.5798), lenses two distinct extended sources into two pairs of arcs (z{sub source} = 0.9818 by nebular [O{sub II}] emission), while the second, HSTJ141833+52435 (the ''Anchor''; z{sub lens} = 0.4625), produces a single pair of arcs (source redshift not yet known). Four less convincing arc/counter-arc and two-image lens candidates are also found and presented for completeness. All three definite lenses are fit reasonably well by simple singular isothermal ellipsoid models including external shear, giving {chi}{sub {nu}}{sup 2}values close to unity. Using the three-dimensional line-of-sight (LOS) information on galaxies from the DEEP2 data, we calculate the convergence and shear contributions {kappa}{sub los} and {gamma}{sub los} to each lens, assuming singular isothermal sphere halos truncated at 200 h{sup -1} …
Date:
July 14, 2006
Creator:
Moustakas, Leonidas A.; Marshall, Phil J.; Newman, Jeffrey A.; Coil, Alison L.; Cooper, Michael C.; Davis, Marc et al.
Object Type:
Report
System:
The UNT Digital Library
Lessons Learned
LLNL turned in 5 Declaration Line Items (DLI's) in 2006. Of these, one was declared completed. We made some changes to streamline our process from 2005, used less money, time and fewer team members. This report is a description of what changes we made in 2006 and what we learned. Many of our core review team had changed from last year, including our Laboratory Director, the Facility safety and security representatives, our Division Leader, and the OPSEC Committee Chair. We were able to hand out an AP Manual to some of them, and briefed all newcomers to the AP process. We first went to the OPSEC Committee and explained what the Additional Protocol process would be for 2006 and solicited their help in locating declarable projects. We utilized the 'three questions' from the AP meeting last year. LLNL has no single place to locate all projects at the laboratory. We talked to Resource Managers and key Managers in the Energy and Environment Directorate and in the Nonproliferation Homeland and International Security Directorate to find applicable projects. We also talked to the Principal Investigators who had projects last year. We reviewed a list of CRADA's and LDRD projects given to us …
Date:
November 14, 2006
Creator:
Dougan, A D & Blair, S
Object Type:
Report
System:
The UNT Digital Library
Thermal and mechanical joints to cryo-cooled silicon monochromatorcrystals
We describe the performance of various materials used as thethermal interface between silicon to silicon and silicon to copper jointswhen operated at ~;120K and loaded with ~;20 watts of thermal power. Wefind that only the indium based silicon-to-silicon joint isreliable.
Date:
July 14, 2006
Creator:
MacDowell, A.; Fakra, S. & Morrison, G.
Object Type:
Article
System:
The UNT Digital Library
Modeling the Cathodic Region in Crevice Corrosion Under a Thin Electrolyte Film Including Particulates
Crevice corrosion may be limited by the capacity of the external cathodic region to support anodic dissolution currents within the crevice. The analysis here focuses on behavior of metal surfaces covered by a thin ({approx}microns) layer of the electrolyte film including particulates. The particulates can affect the cathode current capacity (I{sub total}) by increasing the solution resistance (''volume effect'') and by decreasing the electrode area (''surface effect''). In addition, there can be particulate effects on oxygen reduction kinetics and oxygen transport. This work simulates and characterizes the effect of a uniform particulate monolayer on the cathode current capacity for steady state conditions in the presence of a thin electrolyte film. Particulate configurations with varying particle size, shape, arrangement, volume fraction, and electrode area coverage were numerically modeled as a function of the properties of the system. It is observed that the effects of particles can be fully accounted for in terms of two corrections: the volume blockage effect on the electrolyte resistivity can be correlated using Bruggeman's equation, and the electrode coverage effect can be modeled in terms of a simple area correction to the kinetics expression. For the range of parameters analyzed, applying these two correction factors, cathodes covered …
Date:
March 14, 2006
Creator:
Agarwal, A. S.; Landau, U.; Shan, X. & Payer, J. H.
Object Type:
Report
System:
The UNT Digital Library
An Implementation and Evaluation of the AMLS Method for SparseEigenvalue Problems
We describe an efficient implementation and present aperformance study of an algebraic multilevel sub-structuring (AMLS)method for sparse eigenvalue problems. We assess the time and memoryrequirements associated with the key steps of the algorithm, and compareitwith the shift-and-invert Lanczos algorithm in computational cost. Oureigenvalue problems come from two very different application areas: theaccelerator cavity design and the normal mode vibrational analysis of thepolyethylene particles. We show that the AMLS method, when implementedcarefully, is very competitive with the traditional method in broadapplication areas, especially when large numbers of eigenvalues aresought.
Date:
February 14, 2006
Creator:
Gao, Weiguo; Li, Xiaoye S.; Yang, Chao & Bai, Zhaojun
Object Type:
Article
System:
The UNT Digital Library
Adversary Modeling for Allocation of Effort Across Countermeasures
None
Date:
July 14, 2006
Creator:
Lathrop, J F
Object Type:
Article
System:
The UNT Digital Library
Insertion of a self-splicing intron into the mtDNA of atriploblastic animal
Nephtys longosetosa is a carnivorous polychaete worm that lives in the intertidal and subtidal zones with worldwide distribution (pleijel&rouse2001). Its mitochondrial genome has the characteristics typical of most metazoans: 37 genes; circular molecule; almost no intergenic sequence; and no significant gene rearrangements when compared to other annelid mtDNAs (booremoritz19981995). Ubiquitous features as small intergenic regions and lack of introns suggested that metazoan mtDNAs are under strong selective pressures to reduce their genome size allowing for faster replication requirements (booremoritz19981995Lynch2005). Yet, in 1996 two type I introns were found in the mtDNA of the basal metazoan Metridium senile (FigureX). Breaking a long-standing rule (absence of introns in metazoan mtDNA), this finding was later supported by the further presence of group I introns in other cnidarians. Interestingly, only the class Anthozoa within cnidarians seems to harbor such introns. Although several hundreds of triploblastic metazoan mtDNAs have been sequenced, this study is the first evidence of mitochondrial introns in triploblastic metazoans. The cox1 gene of N. longosetosa has an intron of almost 2 kbs in length. This finding represents as well the first instance of a group II intron (anthozoans harbor group I introns) in all metazoan lineages. Opposite trends are observed within …
Date:
April 14, 2006
Creator:
Valles, Y.; Halanych, K. & Boore, J.L.
Object Type:
Article
System:
The UNT Digital Library
Synthetic Nano-Low Density Lipoprotein as Targeted Drug DeliveryVehicle for Glioblastoma Multiforme
This paper discribes a synthetic low density lipoprotein(LDL) made by complexing a 29 amino acid that consists of a lipid bindingdomain and the LDL receptor binding domain with a lipid microemulsion.The nano-LDL particles were intermdiate in size between LDL and HDL andbound to LDL receptors on GBM brain tumor cells. Synthetic nano-LDLuptake by GBM cells was LDL receptor specific and dependent on cellreceptor number. It is suggested that these synthetic particles can serveas a delivery vehicle for hydophobic anti-tumor drugs by targeting theLDL receptor.
Date:
June 14, 2006
Creator:
Nikanjam, Mina; Blakely, Eleanor A.; Bjornstad, Kathleen A.; Shu,Xiao; Budinger, Thomas F. & Forte, Trudy M.
Object Type:
Article
System:
The UNT Digital Library
Renormalization of Molecular Electronic Levels at Metal-MoleculeInterfaces
None
Date:
November 14, 2006
Creator:
Neaton, Jeffrey B.; Hybertsen, Mark S. & Louie, Steven G.
Object Type:
Article
System:
The UNT Digital Library
Remaining Sites Verification Package for the 116-F-16, PNL Outfall and the 100-F-43, PNL Outfall Spillway, Waste Site Reclassification Form 2006-039
The 116-F-16 waste site is the former Pacific National Laboratories (PNL) Outfall, used to discharge waste effluents from the 100-F Experimental Animal Farm. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date:
September 14, 2006
Creator:
Dittmer, L. M.
Object Type:
Report
System:
The UNT Digital Library
Identification of Severe Multiple Contingencies in Electric PowerSystems
In this work, we propose a computationally feasible approachtodetect severe multiple contingencies. We pose a contingency analysisproblem using a nonlinear optimization framework, which enables ustodetect the fewest possible transmission line outages resulting ina systemfailure of specified severity, and the most severe system failure causedby removing a specified number of transmission lines from service.Illustrations using a three bus system and the IEEE ~;30 bus system aimto exhibit the effectiveness of the proposed approach.
Date:
June 14, 2006
Creator:
Donde, Vaibhav; Lopez, Vanessa; Lesieutre, Bernard; Pinar, Ali; Yang, Chao & Meza, Juan
Object Type:
Article
System:
The UNT Digital Library
Synchronous Parallel Kinetic Monte Carlo
A novel parallel kinetic Monte Carlo (kMC) algorithm formulated on the basis of perfect time synchronicity is presented. The algorithm provides an exact generalization of any standard serial kMC model and is trivially implemented in parallel architectures. We demonstrate the mathematical validity and parallel performance of the method by solving several well-understood problems in diffusion.
Date:
December 14, 2006
Creator:
Mart?nez, E.; Marian, J. & Kalos, M. H.
Object Type:
Article
System:
The UNT Digital Library
R-LODs: Fast LOD-Based Ray Tracing of Massive Models
We present a novel LOD (level-of-detail) algorithm to accelerate ray tracing of massive models. Our approach computes drastic simplifications of the model and the LODs are well integrated with the kd-tree data structure. We introduce a simple and efficient LOD metric to bound the error for primary and secondary rays. The LOD representation has small runtime overhead and our algorithm can be combined with ray coherence techniques and cache-coherent layouts to improve the performance. In practice, the use of LODs can alleviate aliasing artifacts and improve memory coherence. We implement our algorithm on both 32bit and 64bit machines and able to achieve up to 2.20 times improvement in frame rate of rendering models consisting of tens or hundreds of millions of triangles with little loss in image quality.
Date:
February 14, 2006
Creator:
Yoon, S.; Lauterbach, C. & Manocha, D.
Object Type:
Article
System:
The UNT Digital Library
Snake River Sockeye Salmon Habitat and Limnological Research: 2005 Annual Report.
In March 1990, the Shoshone-Bannock Tribes petitioned the National Marine Fisheries Service (NMFS) to list Snake River sockeye salmon (Oncorhynchus nerka) as endangered. Snake River sockeye salmon were officially listed as endangered in November 1991 under the Endangered Species Act (56 FR 58619). In 1991, the Snake River Sockeye Salmon Habitat and Limnological Research Project was implemented. This project is part of an interagency effort to prevent the extinction of the Redfish Lake stock of Snake River sockeye salmon. The Shoshone-Bannock Tribal goal for this project is two tiered: The immediate goal is to increase the population of Snake River sockeye salmon while preserving the unique genetic characteristics of the Evolutionarily Significant Unit (ESU). The Tribes long term goal is to maintain a viable population that warrants delisting and provides Tribal harvest opportunities. The Bonneville Power Administration (BPA) provides funding for this interagency recovery. Collaborators in the recovery effort include the National Oceanic and Atmospheric Administration (NOAA), the Idaho Department of Fish and Game (IDFG), the University of Idaho (UI), and the Shoshone-Bannock Tribes (SBT). This report summarizes activities conducted by Shoshone-Bannock Tribal Fisheries Department personnel during the 2005 calendar year. Project tasks include: (1) monitor limnological parameters of the …
Date:
July 14, 2006
Creator:
Taki, Doug; Kohler, Andre E.; Griswold, Robert G. & Gilliland, Kim
Object Type:
Report
System:
The UNT Digital Library
Detecting the limits of regulatory element conservation anddivergence estimation using pairwise and multiple alignments
Background: Molecular evolutionary studies of noncodingsequences rely on multiple alignments. Yet how multiple alignmentaccuracy varies across sequence types, tree topologies, divergences andtools, and further how this variation impacts specific inferences,remains unclear. Results: Here we develop a molecular evolutionsimulation platform, CisEvolver, with models of background noncoding andtranscription factor binding site evolution, and use simulated alignmentsto systematically examine multiple alignment accuracy and its impact ontwo key molecular evolutionary inferences: transcription factor bindingsite conservation and divergence estimation. We find that the accuracy ofmultiple alignments is determined almost exclusively by the pairwisedivergence distance of the two most diverged species and that additionalspecies have a negligible influence on alignment accuracy. Conservedtranscription factor binding sites align better than surroundingnoncoding DNA yet are often found to be misaligned at relatively shortdivergence distances, such that studies of binding site gain and losscould easily be confounded by alignment error. Divergence estimates frommultiple alignments tend to be overestimated at short divergencedistances but reach a tool specific divergence at which they cease toincrease, leading to underestimation at long divergences. Our moststriking finding was that overall alignment accuracy, binding sitealignment accuracy and divergence estimation accuracy vary greatly acrossbranches in a tree and are most accurate for terminal branches connectingsister taxa and least …
Date:
August 14, 2006
Creator:
Pollard, Daniel A.; Moses, Alan M.; Iyer, Venky N. & Eisen,Michael B.
Object Type:
Article
System:
The UNT Digital Library