Final Technical Report for USDOE Grant No. DE-FG02-96ER14675 Supermolecular Photosynthetic Arrays: Construction, Characterization, Exploration and Utilization (open access)

Final Technical Report for USDOE Grant No. DE-FG02-96ER14675 Supermolecular Photosynthetic Arrays: Construction, Characterization, Exploration and Utilization

Biological processes provide paradigms for the development of solar energy devices of practical utility. In nature, the light harvesting -complexes (LHCs) are not chemically active. However, with unnatural chemical oxidation by potassium ferricyanide, cation free radicals of bacteriochlorophyll (BChl) can be formed in the light harvesting complex 1 (LH1) of Rhodobacter sphaeroides. Based on EPR studies, the site of the BChl{sup +} cations move rather freely about the LH1 complex as in a molecular wire. These molecular wires function in the frozen, solid state. This work seeks to understand better how nature controls electron transfer in some of its molecular wires. To investigate the nature of electron-hole transfer we have e.onducted both electron paramagnetic resonance (EPR) and electron nuclear double resonance (ENDOR) experiments on oxidized LH1 complexes. Progress has been achieved in two main areas: EPR studies of the role of ferricyanide in the molecular wire nature of oxidized LH1; and ENDOR studies of oxidized LH1 at 80K.
Date: December 13, 2009
Creator: Norris, James
Object Type: Report
System: The UNT Digital Library
The Full Function Test Explosive Generator (open access)

The Full Function Test Explosive Generator

We have conducted three tests of a new pulsed power device called the Full Function Test (FFT). These tests represented the culmination of an effort to establish a high energy pulsed power capability based on high explosive pulsed power (HEPP) technology. This involved an extensive computational modeling, engineering, fabrication, and fielding effort. The experiments were highly successful and a new US record for magnetic energy was obtained.
Date: December 13, 2009
Creator: Reisman, D. B.; Javedani, J. B.; Griffith, L. V.; Ellsworth, G. F.; Kuklo, R. M.; Goerz, D. A. et al.
Object Type: Article
System: The UNT Digital Library
THE HIGH TEMPERATURE CHEMICAL REACTIVITY OF LI2O (open access)

THE HIGH TEMPERATURE CHEMICAL REACTIVITY OF LI2O

The ultimate purpose of this study was to investigate the use of a Li-Ca mixture for direct reduction of actinide oxides to actinide metals at temperatures below 1500 C. For such a process to be successful, the products of the reduction reaction, actinide metals, Li{sub 2}O, and CaO, must all be liquid at the reaction temperature so the resulting actinide metal can coalesce and be recovered as a monolith. Since the established melting temperature of Li{sub 2}O is in the range 1427-1700 C and the melting temperature of CaO is 2654 C, the Li{sub 2}O-CaO (lithium oxidecalcium oxide) pseudo-binary system was investigated in an attempt to identify the presence of low-melting eutectic compositions. The results of our investigation indicate that there is no evidence of ternary Li-Ca-O phases or solutions melting below 1200 C. In the 1200-1500 C range utilizing MgO crucibles, there is some evidence for the formation of a ternary phase; however, it was not possible to determine the phase composition. The results of experiments performed with ZrO{sub 2} crucibles in the same temperature range did not show the formation of the possible ternary phase seen in the earlier experiment involving MgO crucibles, so it was not possible …
Date: November 13, 2009
Creator: Kessinger, G. & Missimer, D.
Object Type: Article
System: The UNT Digital Library
NEPTUNIUM IV AND V SORPTIN TO END-MEMBER SUBSURFACE SEDIMENTS TO THE SAVANNAH RIVER SITE (open access)

NEPTUNIUM IV AND V SORPTIN TO END-MEMBER SUBSURFACE SEDIMENTS TO THE SAVANNAH RIVER SITE

Migration of Np through the subsurface is expected to be primarily controlled by sorption to sediments. Therefore, understanding and quantifying Np sorption to sediments and sediments from the Savannah River Site (SRS) is vital to ensure safe disposal of Np bearing wastes. In this work, Np sorption to two sediments representing the geological extremes with respect to sorption properties expected in the SRS subsurface environment (named 'subsurface sandy sediment' and 'subsurface clayey sediment') was examined under a variety of conditions. First a series of baseline sorption tests at pH 5.5 under an oxic atmosphere was performed to understand Np sorption under typical subsurface conditions. These experiments indicated that the baseline K{sub d} values for the subsurface sandy and subsurface clayey sediments are 4.26 {+-} 0.24 L kg{sup -1} and 9.05 {+-} 0.61 L kg{sup -1}, respectively. These Np K{sub d} values of SRS sediments are the first to be reported since Sheppard et al. (1979). The previous values were 0.25 and 0.16 L kg{sup -1} for a low pH sandy sediment. To examine a possible range of K{sub d} values under various environmental scenarios, the effects of natural organic matter (NOM, also a surrogate for cellulose degradation products), the presence …
Date: November 13, 2009
Creator: Kaplan, D.
Object Type: Report
System: The UNT Digital Library
Preliminary simulations of planned experiments to study the impact of trace gases on the capacity of the Weyburn-Midale field to store carbon dioxide (open access)

Preliminary simulations of planned experiments to study the impact of trace gases on the capacity of the Weyburn-Midale field to store carbon dioxide

The CO{sub 2} stream injecting into the Weyburn-Midale field can be generally classified as a reducing stream with residual H{sub 2}S and low-molecular weight hydrocarbons. The composition of the CO{sub 2} gas stream from the Dakota Gasification Company is reported to be 95% CO{sub 2}, 4% hydrocarbons, and 1% H{sub 2}S by volume (Huxley 2006). In addition to the H{sub 2}S introduced at the injection wells, significant concentrations of H{sub 2}S are thought to have been produced in-situ by sulfate reducing bacteria from previous water floods for enhanced oil production. Produced gas compositions range in H{sub 2}S concentrations from 1 to 6 volume percent. The produced gas, including the trace impurities, is re-injected into the field. Although there is no evidence for inorganic reduction of SO{sub 4}{sup 2-} to H{sub 2}S at the Weyburn-Midale field, Sitchler and Kazuba (2009) suggest that SO{sub 4}{sup 2-} can be inorganically reduced to elemental sulfur in highly reducing environments based on a natural analog study of the Madison Formation in Wyoming. They propose that elevated concentrations of CO{sub 2} dissolve anhydrite to produce the sulfate that is then reduced. Oxidizing CO{sub 2} streams with residual O{sub 2} and SO{sub 2} typical of streams captured …
Date: November 13, 2009
Creator: Carroll, S & Hao, Y
Object Type: Report
System: The UNT Digital Library
Program for the Inspection of Nickel Alloy Components Report from the Program’s Steering Committee: Inspection of Bottom-Mounted Instrumentation Nozzles Round Robin (open access)

Program for the Inspection of Nickel Alloy Components Report from the Program’s Steering Committee: Inspection of Bottom-Mounted Instrumentation Nozzles Round Robin

The U.S. Nuclear Regulatory Commission (NRC) executed agreements with organizations in Japan, Sweden, South Korea, Finland, and the United States to establish the Program for the Inspection of Nickel Alloy Components (PINC).
Date: November 13, 2009
Creator: Cumblidge, Stephen E.; Heasler, Patrick G.; Doctor, Steven R. & Taylor, Theodore T.
Object Type: Report
System: The UNT Digital Library
RESULTS FOR THE THIRD QUARTER 2009 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS (open access)

RESULTS FOR THE THIRD QUARTER 2009 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS

This report details the chemical and radionuclide contaminant results for the characterization of the 2009 Third Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC). Information from this characterization will be used by Liquid Waste Operations (LWO) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System. Recently, a review of the radionuclide inventory in Saltstone Vaults 1 and 4 identified several additional radionuclides, not currently in the WAC, which require quantification ({sup 40}K, {sup 108m}Ag, {sup 133}Ba, {sup 207}Bi, {sup 227}Ac, {sup 228}Ra, {sup 228}Th, {sup 231}Pa, {sup 247}Cm, {sup 249}Cf, {sup 251}Cf). In addition, several of the radionuclides previously reported with minimum detection limits below the requirements listed in the WAC required analysis with reduced detection limits to support future inventory reporting requirements ({sup 22}Na, {sup 26}Al, {sup 59}Ni, {sup 94}Nb, {sup 106}Ru, {sup 144}Ce, {sup 152}Eu, {sup 155}Eu, {sup 226}Ra). This added scope was formally requested in a revision to the standing Technical Task Request for CY2009 Saltstone support and is further discussed …
Date: November 13, 2009
Creator: Reigel, M.; Diprete, C. & Bibler, N.
Object Type: Report
System: The UNT Digital Library
Upper Limits on the Number of Small Bodies in Sedna-Like Orbits by the TAOS Project (open access)

Upper Limits on the Number of Small Bodies in Sedna-Like Orbits by the TAOS Project

We present the results of a search for occultation events by objects at distances between 100 and 1000 AU in lightcurves from the Taiwanese-American Occultation Survey (TAOS). We searched for consecutive, shallow flux reductions in the stellar lightcurves obtained by our survey between 7 February 2005 and 31 December 2006 with a total of {approx} 4.5 x 10{sup 9} three-telescope simultaneous photometric measurements. No events were detected, allowing us to set upper limits on the number density as a function of size and distance of objects in Sedna-like orbits, using simple models.
Date: November 13, 2009
Creator: Wang, J.; Lehner, M. J.; Zhang, Z.; Bianco, F. B.; Alcock, C.; Chen, W. et al.
Object Type: Article
System: The UNT Digital Library
Computational fluid dynamics modeling of two-phase flow in a BWR fuel assembly. Final CRADA Report. (open access)

Computational fluid dynamics modeling of two-phase flow in a BWR fuel assembly. Final CRADA Report.

A direct numerical simulation capability for two-phase flows with heat transfer in complex geometries can considerably reduce the hardware development cycle, facilitate the optimization and reduce the costs of testing of various industrial facilities, such as nuclear power plants, steam generators, steam condensers, liquid cooling systems, heat exchangers, distillers, and boilers. Specifically, the phenomena occurring in a two-phase coolant flow in a BWR (Boiling Water Reactor) fuel assembly include coolant phase changes and multiple flow regimes which directly influence the coolant interaction with fuel assembly and, ultimately, the reactor performance. Traditionally, the best analysis tools for this purpose of two-phase flow phenomena inside the BWR fuel assembly have been the sub-channel codes. However, the resolution of these codes is too coarse for analyzing the detailed intra-assembly flow patterns, such as flow around a spacer element. Advanced CFD (Computational Fluid Dynamics) codes provide a potential for detailed 3D simulations of coolant flow inside a fuel assembly, including flow around a spacer element using more fundamental physical models of flow regimes and phase interactions than sub-channel codes. Such models can extend the code applicability to a wider range of situations, which is highly important for increasing the efficiency and to prevent accidents.
Date: October 13, 2009
Creator: Tentner, A.
Object Type: Report
System: The UNT Digital Library
Final report for grant DE-FG02-06ER64182: "Evaluation and Improvement of the Cloud Resolving Model Component of the Multi-Scale Modeling Framework" (open access)

Final report for grant DE-FG02-06ER64182: "Evaluation and Improvement of the Cloud Resolving Model Component of the Multi-Scale Modeling Framework"

The overall aim of the larger collaborative effort of which this project was part was to evaluate and improve the cloud system resolving model (CSRM) at the heart of the multi-scale modeling framework (MMF). Our task at the University of Colorado our effort was to develop methods that would let us evaluate the performance of cloud-scale models at the ARM SGP site using ARM remote sensing products.
Date: October 13, 2009
Creator: Pincus, Robert
Object Type: Report
System: The UNT Digital Library
WInd-and-react Bi-2212 coil development for accelerator magnets (open access)

WInd-and-react Bi-2212 coil development for accelerator magnets

Sub-scale coils are being manufactured and tested at Lawrence Berkeley National Laboratory in order to develop wind-and-react Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (Bi-2212) magnet technology for future graded accelerator magnet use. Previous Bi-2212 coils showed significant leakage of the conductors core constituents to the environment, which can occur during the partial melt reaction around 890 C in pure oxygen. The main origin of the observed leakage is intrinsic leakage of the wires, and the issue is therefore being addressed at the wire manufacturing level. We report on further compatibility studies, and the performance of new sub-scale coils that were manufactured using improved conductors. These coils exhibit significantly reduced leakage, and carry currents that are about 70% of the witness wire critical current (I{sub c}). The coils demonstrate, for the first time, the feasibility of round wire Bi-2212 conductors for accelerator magnet technology use. Successful high temperature superconductor coil technology will enable the manufacture of graded accelerator magnets that can surpass the, already closely approached, intrinsic magnetic field limitations of Nb-based superconducting magnets.
Date: October 13, 2009
Creator: Godeke, A.; Acosta, P.; Cheng, D.; Dietderich, D. R.; Mentink, M. G. T.; Prestemon, S. O. et al.
Object Type: Article
System: The UNT Digital Library
Cable deformation simulation and a hierarchical framework for Nb3Sn Rutherford cables (open access)

Cable deformation simulation and a hierarchical framework for Nb3Sn Rutherford cables

Knowledge of the three-dimensional strain state induced in the superconducting filaments due to loads on Rutherford cables is essential to analyze the performance of Nb{sub 3}Sn magnets. Due to the large range of length scales involved, we develop a hierarchical computational scheme that includes models at both the cable and strand levels. At the Rutherford cable level, where the strands are treated as a homogeneous medium, a three-dimensional computational model is developed to determine the deformed shape of the cable that can subsequently be used to determine the strain state under specified loading conditions, which may be of thermal, magnetic, and mechanical origins. The results can then be transferred to the model at the strand/macro-filament level for rod restack process (RRP) strands, where the geometric details of the strand are included. This hierarchical scheme can be used to estimate the three-dimensional strain state in the conductor as well as to determine the effective properties of the strands and cables from the properties of individual components. Examples of the modeling results obtained for the orthotropic mechanical properties of the Rutherford cables are presented.
Date: September 13, 2009
Creator: Arbelaez, D.; Prestemon, S. O.; Ferracin, P.; Godeke, A.; Dietderich, D. R. & Sabbi, G.
Object Type: Article
System: The UNT Digital Library
NSLS II Vacuum System (open access)

NSLS II Vacuum System

National Synchrotron Light Source II, being constructed at Brookhaven, is a 3-GeV, 500 mA, 3rd generation synchrotron radiation facility with ultra low emittance electron beams. The storage ring vacuum system has a circumference of 792 m and consists of over 250 vacuum chambers with a simulated average operating pressure of less than 1 x 10{sup -9} mbar. A summary of the update design of the vacuum system including girder supports of the chambers, gauges, vacuum pumps, bellows, beam position monitors and simulation of the average pressure will be shown. A brief description of the techniques and procedures for cleaning and mounting the chambers are given.
Date: September 13, 2009
Creator: Ferreira, M.; Doom, L.; Hseuh, H.; Longo, C.; Settepani, P.; Wilson, K. et al.
Object Type: Article
System: The UNT Digital Library
Structural Characterization of Doped GaSb Single Crystals by X-ray Topography (open access)

Structural Characterization of Doped GaSb Single Crystals by X-ray Topography

We characterized GaSb single crystals containing different dopants (Al, Cd and Te), grown by the Czochralski method, by x-ray topography and high angular resolution x-ray diffraction. Lang topography revealed dislocations parallel and perpendicular to the crystal's surface. Double-crystal GaSb 333 x-ray topography shows dislocations and vertical stripes than can be associated with circular growth bands. We compared our high-angular resolution x-ray diffraction measurements (rocking curves) with the findings predicted by the dynamical theory of x-ray diffraction. These measurements show that our GaSb single crystals have a relative variation in the lattice parameter ({Delta}d/d) on the order of 10{sup -5}. This means that they can be used as electronic devices (detectors, for example) and as x-ray monochromators.
Date: September 13, 2009
Creator: Honnicke, M. G.; Mazzaro, I.; Manica, J.; Benine, E.; da Costa, E. M.; Dedavid, B. A. et al.
Object Type: Article
System: The UNT Digital Library
Test results of TQS03: a LARP shell-based Nb3Sn quadrupole using 108/127 conductor (open access)

Test results of TQS03: a LARP shell-based Nb3Sn quadrupole using 108/127 conductor

Future insertion quadrupoles with large apertures and high gradients will be required for the Phase II luminosity upgrade (10{sup 35} cm{sup -2}s{sup -1}) of the Large Hadron Collider (LHC). Although improved designs, based on NbTi, are being considered as an intermediate step for the Phase I upgrade, the Nb{sub 3}Sn conductor is presently the best option that meets the ultimate performance goals for both operating field and temperature margin. As part of the development of Nb{sub 3}Sn magnet technology, the LHC Accelerator Research Program (LARP) developed and tested several 1-meter long, 90-mm aperture Nb{sub 3}Sn quadrupoles. The first two series of magnet used OST MJR 54/61 (TQ01 series) and OST RRP 54/61 (TQ02 series) strands. The third series (TQ03) used OST RRP 108/127 conductor. The larger number of sub-elements and the consequent reduction of the effective filament size, together with an increased fraction of copper and a lower Jc were expected to improve the conductor stability. The new coils were tested in the TQS03 series using a shell structure assembled with keys and bladders. The objective of the first test (TQS03a) was to evaluate the performances of the 108/127 conductor and, in particular, its behaviour at 1.9 K, while the …
Date: September 13, 2009
Creator: Felice, H.; Ambrosio, G.; Bajko, M.; Barzi, E.; Bordini, B.; Bossert, R. et al.
Object Type: Article
System: The UNT Digital Library
Theory of AC Loss in Cables with 2G HTS Wire (open access)

Theory of AC Loss in Cables with 2G HTS Wire

While considerable work has been done to understand AC losses in power cables made of first generation (1G) high temperature superconductor (HTS) wires, use of second generation (2G) HTS wires brings in some new considerations. The high critical current density of the HTS layer 2G wire reduces the surface superconductor hysteretic losses. Instead, gap and polygonal losses, flux transfer losses in imbalanced two layer cables and ferromagnetic losses for wires with NiW substrates constitute the principal contributions. Current imbalance and losses associated with the magnetic substrate can be minimized by orienting the substrates of the inner winding inward and the outer winding outward.
Date: September 13, 2009
Creator: Clem, J.R. & Malozemoff, A.P.
Object Type: Article
System: The UNT Digital Library
ACRF Instrumentation Status and Information July 2009 (open access)

ACRF Instrumentation Status and Information July 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: August 13, 2009
Creator: Voyles, J. W.
Object Type: Report
System: The UNT Digital Library
EFRT M-12 Issue Resolution: Comparison of Filter Performance at PEP and CUF Scale (open access)

EFRT M-12 Issue Resolution: Comparison of Filter Performance at PEP and CUF Scale

Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed and constructed and is to be operated as part of a plan to respond to issue M12, Undemonstrated Leaching Processes. The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed-preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF). In both scenarios, 19-M sodium hydroxide solution (NaOH, caustic) is …
Date: August 13, 2009
Creator: Daniel, Richard C.; Billing, Justin M.; Bontha, Jagannadha R.; Brown, Christopher F.; Eslinger, Paul W.; Hanson, Brady D. et al.
Object Type: Report
System: The UNT Digital Library
Improved Spatial Resolution For Reflection Mode Infrared Spectromicroscopy (open access)

Improved Spatial Resolution For Reflection Mode Infrared Spectromicroscopy

Standard commercial infrared microscopes operating in reflection mode use a mirror to direct the reflected light from the sample to the detector. This mirror blocks about half of the incident light, however, and thus degrades the spatial resolution by reducing the numerical aperture of the objective. Here, we replace the mirror with a 50% beamsplitter to allow full illumination of the objective and retain a way to direct the reflected light to the detector. The improved spatial resolution is demonstrated using a microscope coupled to a synchrotron source.
Date: August 13, 2009
Creator: Bechtel, Hans A.; Martin, Michael C.; May, T. E. & Lerch, Philippe
Object Type: Article
System: The UNT Digital Library
Interfacial Widths of Conjugated Polymer Bilayers (open access)

Interfacial Widths of Conjugated Polymer Bilayers

The interfaces of conjugated polyelectrolyte (CPE)/poly[2-methoxy-5-(2{prime}-ethylhexyloxy)-p-phenylene vinylene] (MEH-PPV) bilayers cast from differential solvents are shown by resonant soft X-ray reflectivity (RSoXR) to be very smooth and sharp. The chemical interdiffusion due to casting is limited to less than 0.6 nm, and the interface created is thus nearly 'molecularly' sharp. These results demonstrate for the first time and with high precision that the nonpolar MEH-PPV layer is not much disturbed by casting the CPE layer from a polar solvent. A baseline is established for understanding the role of interfacial structure in determining the performance of CPE-based polymer light-emitting diodes. More broadly, we anticipate further applications of RSoXR as an important tool in achieving a deeper understanding of other multilayer organic optoelectronic devices, including multilayer photovoltaic devices.
Date: August 13, 2009
Creator: NCSU; Berkeley, UC; UCSB; Source, Advanced Light; Garcia, Andres; Yan, Hongping et al.
Object Type: Article
System: The UNT Digital Library
Progress Testing TRANSP-TORIC Simulations of ICRH in JE (open access)

Progress Testing TRANSP-TORIC Simulations of ICRH in JE

Introduction - Ion Cyclotron Range of Frequency (ICRF) waves are candidates for heating (ICRH), current drive, and possible flow drive in ITER and future tokamaks. There are considerable challenges developing the technology of ICRF systems and the tools for assessing effects on plasma performance. These tools are important both for guiding present experiments and for indicating efforts for future research. This paper addresses some of the tools for simulating ICRH. The TORIC ICRF full-wave code [1] solves the kinetic wave equation in 2D axisymmetric equilibria. TORIC solves Maxwell's Equations for a fixed wave frequency with a linear plasma response in a mixed spectral-finite element basis. The antenna is modelled as a sheet current. A kinetic model for the plasma dielectric response is derived using an Eikonal ansatz.
Date: August 13, 2009
Creator: Budny, R V; McCune, D; Mayoral, M -L; Ongena, J; Van Eester, D; Conboy, J et al.
Object Type: Article
System: The UNT Digital Library
Proliferation Risks of Fusion Energy: Clandestine Production, Covert Production, and Breakout (open access)

Proliferation Risks of Fusion Energy: Clandestine Production, Covert Production, and Breakout

Nuclear proliferation risks from fusion associated with access to weapon-usable material can be divided into three main categories: 1) clandestine production of fissile material in an undeclared facility, 2) covert production of such material in a declared and safeguarded facility, and 3) use of a declared facility in a breakout scenario, in which a state begins production of fissile material without concealing the effort. In this paper we address each of these categories of risk from fusion. For each case, we find that the proliferation risk from fusion systems can be much lower than the equivalent risk from fission systems, if commercial fusion systems are designed to accommodate appropriate safeguards.
Date: August 13, 2009
Creator: R.J. Goldston, A. Glaser, A.F. Ross
Object Type: Article
System: The UNT Digital Library
Protect and Restore the Upper Lochsa : Annual Progress Report, May 2008 – April 2009. (open access)

Protect and Restore the Upper Lochsa : Annual Progress Report, May 2008 – April 2009.

The Upper Lochsa watersheds included in the project contain critical spawning and rearing habitat for anadromous and resident fish (Clearwater National Forest 1999). Species that depend on the tributary habitat include spring chinook salmon (Oncorhynchus tshawytscha), Snake River summer steelhead (Oncorhynchus mykiss), bull trout (Salvelinus confluentes), and westslope cutthroat trout (Oncorhynchus clarki lewisi). Steelhead and bull trout populations are currently listed as Threatened under the Endangered Species Act (ESA), and westslope cutthroat trout has been petitioned for listing. Both out-of-basin and in-basin factors threaten fish populations in the Lochsa Drainage (Clearwater Subbasin Plan 2003). Out-of-basin factors include the hydroelectric system and ocean conditions, while in-basin factors include a variety of management activities leading to habitat degradation. This project is implemented under Bonneville Power Administration's Fish and Wildlife program in order to meet National Marine Fisheries Service requirements to offset losses caused by the operation of the hydrosystem by improving tributary habitats to promote increased productivity of salmon and steelhead. The Clearwater Subbasin Plan (2003) defines limiting factors to fisheries in the area as watershed disturbances, habitat degradation, sediment, temperature, and connectivity.
Date: August 13, 2009
Creator: Lloyd, Rebecca & Forestieri, David
Object Type: Report
System: The UNT Digital Library
Reconciling FTIR Spectroscopy with Top-off Operations at the Advanced Light Source (open access)

Reconciling FTIR Spectroscopy with Top-off Operations at the Advanced Light Source

Top-off operations is a quasi-continuous injection mode that increases the flux and brightness of a synchrotron source and improves thermal stability of optical components by maintaining a constant current in the storage ring. Although the increased and constant flux is advantageous for FTIR measurements, the frequent injections (about one every 30 seconds in the ALS case) introduce artifacts into the spectrum by creating spikes in the interferogram data. These spikes are caused by brief beam motion during the injection event. Here, we describe our efforts to minimize the effects of top-off generated interferogram spikes on several FTIR spectrometers. They include using a fast feedback mirror system to correct for beam motion and a gating signal to inhibit interferogram collection during a top-off injection.
Date: August 13, 2009
Creator: Vernoud, Laetitia; Bechtel, Hans A.; Borondics, Ferenc & Martin, Michael C.
Object Type: Article
System: The UNT Digital Library