The Impact Of Lithium Wall Coatings On NSTX Discharges And The Engineering Of The Lithium Tokamak eXperiment (LTX) (open access)

The Impact Of Lithium Wall Coatings On NSTX Discharges And The Engineering Of The Lithium Tokamak eXperiment (LTX)

Recent experiments on the National Spherical Torus eXperiment (NSTX) have shown the benefits of solid lithium coatings on carbon PFC's to diverted plasma performance, in both Land H- mode confinement regimes. Better particle control, with decreased inductive flux consumption, and increased electron temperature, ion temperature, energy confinement time, and DD neutron rate were observed. Successive increases in lithium coverage resulted in the complete suppression of ELM activity in H-mode discharges. A liquid lithium divertor (LLD), which will employ the porous molybdenum surface developed for the LTX shell, is being installed on NSTX for the 2010 run period, and will provide comparisons between liquid walls in the Lithium Tokamak eXperiment (LTX) and liquid divertor targets in NSTX. LTX, which recently began operations at the Princeton Plasma Physics Laboratory, is the world's first confinement experiment with full liquid metal plasma-facing components (PFCs). All materials and construction techniques in LTX are compatible with liquid lithium. LTX employs an inner, heated, stainless steel-faced liner or shell, which will be lithium-coated. In order to ensure that lithium adheres to the shell, it is designed to operate at up to 500 - 600 oC to promote wetting of the stainless by the lithium, providing the first …
Date: March 18, 2010
Creator: Majeski, R.; Kugel, H. & Kaita, R.
Object Type: Report
System: The UNT Digital Library
Cylindrical Hall Thrusters with Permanent Magnets (open access)

Cylindrical Hall Thrusters with Permanent Magnets

The use of permanent magnets instead of electromagnet coils for low power Hall thrusters can offer a significant reduction of both the total electric power consumption and the thruster mass. Two permanent magnet versions of the miniaturized cylindrical Hall thruster (CHT) of different overall dimensions were operated in the power range of 50W-300 W. The discharge and plasma plume measurements revealed that the CHT thrusters with permanent magnets and electromagnet coils operate rather differently. In particular, the angular ion current density distribution from the permanent magnet thrusters has an unusual halo shape, with a majority of high energy ions flowing at large angles with respect to the thruster centerline. Differences in the magnetic field topology outside the thruster channel and in the vicinity of the channel exit are likely responsible for the differences in the plume characteristics measured for the CHTs with electromagnets and permanent magnets. It is shown that the presence of the reversing-direction or cusp-type magnetic field configuration inside the thruster channel without a strong axial magnetic field outside the thruster channel does not lead to the halo plasma plume from the CHT. __________________________________________________
Date: October 18, 2010
Creator: Raitses, Yevgeny; Merino, Enrique & Fisch, Nathaniel J.
Object Type: Report
System: The UNT Digital Library
Biosafety Manual (open access)

Biosafety Manual

Work with or potential exposure to biological materials in the course of performing research or other work activities at Lawrence Berkeley National Laboratory (LBNL) must be conducted in a safe, ethical, environmentally sound, and compliant manner. Work must be conducted in accordance with established biosafety standards, the principles and functions of Integrated Safety Management (ISM), this Biosafety Manual, Chapter 26 (Biosafety) of the Health and Safety Manual (PUB-3000), and applicable standards and LBNL policies. The purpose of the Biosafety Program is to protect workers, the public, agriculture, and the environment from exposure to biological agents or materials that may cause disease or other detrimental effects in humans, animals, or plants. This manual provides workers; line management; Environment, Health, and Safety (EH&S) Division staff; Institutional Biosafety Committee (IBC) members; and others with a comprehensive overview of biosafety principles, requirements from biosafety standards, and measures needed to control biological risks in work activities and facilities at LBNL.
Date: May 18, 2010
Creator: King, Bruce W.
Object Type: Report
System: The UNT Digital Library
Magnetic Measurements of the Background Field in the Undulator Hall with Ductwork and Cable Trays (open access)

Magnetic Measurements of the Background Field in the Undulator Hall with Ductwork and Cable Trays

The duct work and cable trays present in the undulator hall facility are made out of potentially magnetically active materials. This note describes a measurement done to make a comparison between the fields in the undulator hall with the duct work and cable trays present and in the Magnetic Measurement Facility. In order for the undulators to have the proper tuning, the background magnetic field in the Undulator Hall must agree with the background field in the Magnetic Measurements Facility within 0.5 gauss. To verify that this was the case, measurements were taken along the length of the undulator hall, and the point measurements were compared to the mean field which was measured on the MMF test bench. This set of measurements was conducted with most of the cable trays and duct work in place, but without any of the magnet stands in place.
Date: November 18, 2010
Creator: Fisher, Andrew; Nuhn, Heinz-Dieter & Welch, James
Object Type: Report
System: The UNT Digital Library
Final report for grant number DE-FG02-06ER64244 to the University of Idaho (RW Smith)-coupling between flow and precipitation in heterogeneous subsurface environments and effects on contaminant fate and transport (open access)

Final report for grant number DE-FG02-06ER64244 to the University of Idaho (RW Smith)-coupling between flow and precipitation in heterogeneous subsurface environments and effects on contaminant fate and transport

Engineered remediation strategies for inducing mineral precipitation in the subsurface typically involve the introduction of at least one reactant either by direct injection or by in situ generation. The localization of reactant sources means a wide range of saturation states and ion ratios will be created as reactants are mixed: These conditions together can result in a wide range of precipitation rates, as well as impact which mineral phase precipitates. This is potentially important for the capacity of the precipitates to take up of trace metal contaminants, for their long term stability. Aragonite, for example, is able to sequester a larger amount of Sr than calcite. However, aragonite is less stable under typical groundwater conditions, and so may release sequestered Sr over time as the aragonite transforms to a more stable phase. In addition, previous experimental studies have indicated that other system constituents may influence calcium carbonate precipitation and consequently the Sr uptake potential of a system. For example, dissolved organic carbon (at levels typical of groundwaters) can suppress crystal growth. As a result, the continuous nucleation of small crystals, rather than growth of existing crystals, may be the dominant mode of precipitation. This has the potential for greater uptake …
Date: June 18, 2010
Creator: Smith, Robert W.; Beig, Mikala S.; Gebrehiwet, Tsigabu; Corriveau, Catherine E.; Redden, George & Fujita, Yoshiko
Object Type: Report
System: The UNT Digital Library
Girder Alignment Plan (open access)

Girder Alignment Plan

The girders for the LCLS undulator system contain components which must be aligned with high accuracy relative to each other. The alignment is one of the last steps before the girders go into the tunnel, so the alignment must be done efficiently, on a tight schedule. This note documents the alignment plan which includes efficiency and high accuracy. The motivation for girder alignment involves the following considerations. Using beam based alignment, the girder position will be adjusted until the beam goes through the center of the quadrupole and beam finder wire. For the machine to work properly, the undulator axis must be on this line and the center of the undulator beam pipe must be on this line. The physics reasons for the undulator axis and undulator beam pipe axis to be centered on the beam are different, but the alignment tolerance for both are similar. In addition, the beam position monitor must be centered on the beam to preserve its calibration. Thus, the undulator, undulator beam pipe, quadrupole, beam finder wire, and beam position monitor axes must all be aligned to a common line. All relative alignments are equally important, not just, for example, between quadrupole and undulator. We …
Date: November 18, 2010
Creator: Wolf, Zachary; Ruland, Robert; LeCocq, Catherine; Lundahl, Eric; Levashov, Yurii; Reese, Ed et al.
Object Type: Report
System: The UNT Digital Library
Imaging nanoscale magnetic structures with polarized soft x-ray photons (open access)

Imaging nanoscale magnetic structures with polarized soft x-ray photons

Imaging nanoscale magnetic structures and their fast dynamics is scientifically interesting and technologically of highest relevance. The combination of circularly polarized soft X-ray photons which provide a strong X-ray magnetic circular dichroism effect at characteristic X-ray absorption edges, with a high resolution soft X-ray microscope utilizing Fresnel zone plate optics allows to study in a unique way the stochastical behavior in the magnetization reversal process of thin films and the ultrafast dynamics of magnetic vortices and domain walls in confined ferromagnetic structures. Future sources of fsec short and high intense soft X-ray photon pulses hold the promise of magnetic imaging down to fundamental magnetic length and time scales.
Date: January 18, 2010
Creator: Fischer, P. & Im, M.-Y.
Object Type: Article
System: The UNT Digital Library
MODELING THE IMPACT OF ELEVATED MERCURY IN DEFENSE WASTE PROCESSING FACILITY MELTER FEED ON THE MELTER OFF-GAS SYSTEM-PRELIMINARY REPORT (open access)

MODELING THE IMPACT OF ELEVATED MERCURY IN DEFENSE WASTE PROCESSING FACILITY MELTER FEED ON THE MELTER OFF-GAS SYSTEM-PRELIMINARY REPORT

The Defense Waste Processing Facility (DWPF) is currently evaluating an alternative Chemical Process Cell (CPC) flowsheet to increase throughput. It includes removal of the steam-stripping step, which would significantly reduce the CPC processing time and lessen the sampling needs. However, its downside would be to send 100% of the mercury that comes in with the sludge straight to the melter. For example, the new mercury content in the Sludge Batch 5 (SB5) melter feed is projected to be 25 times higher than that in the SB4 with nominal steam stripping of mercury. This task was initiated to study the impact of the worst-case scenario of zero-mercury-removal in the CPC on the DWPF melter offgas system. It is stressed that this study is intended to be scoping in nature, so the results presented in this report are preliminary. In order to study the impact of elevated mercury levels in the feed, it is necessary to be able to predict how mercury would speciate in the melter exhaust under varying melter operating conditions. A homogeneous gas-phase oxidation model of mercury by chloride was developed to do just that. The model contains two critical parameters pertaining to the partitioning of chloride among HCl, …
Date: August 18, 2010
Creator: Zamecnik, J. & Choi, A.
Object Type: Report
System: The UNT Digital Library
Illumina Production Sequencing at the DOE Joint Genome Institute - Workflow and Optimizations (open access)

Illumina Production Sequencing at the DOE Joint Genome Institute - Workflow and Optimizations

The U.S. Department of Energy (DOE) Joint Genome Institute?s (JGI) Production Sequencing group is committed to the generation of high-quality genomic DNA sequence to support the DOE mission areas of renewable energy generation, global carbon management, and environmental characterization and clean-up. Within the JGI?s Production Sequencing group, the Illumina Genome Analyzer pipeline has been established as one of three sequencing platforms, along with Roche/454 and ABI/Sanger. Optimization of the Illumina pipeline has been ongoing with the aim of continual process improvement of the laboratory workflow. These process improvement projects are being led by the JGI?s Process Optimization, Sequencing Technologies, Instrumentation& Engineering, and the New Technology Production groups. Primary focus has been on improving the procedural ergonomics and the technicians? operating environment, reducing manually intensive technician operations with different tools, reducing associated production costs, and improving the overall process and generated sequence quality. The U.S. DOE JGI was established in 1997 in Walnut Creek, CA, to unite the expertise and resources of five national laboratories? Lawrence Berkeley, Lawrence Livermore, Los Alamos, Oak Ridge, and Pacific Northwest ? along with HudsonAlpha Institute for Biotechnology. JGI is operated by the University of California for the U.S. DOE.
Date: June 18, 2010
Creator: Tarver, Angela; Fern, Alison; Diego, Matthew San; Kennedy, Megan; Zane, Matthew; Daum, Christopher et al.
Object Type: Report
System: The UNT Digital Library
Manufacturing Ultra-Precision Meso-scale Products by Coining (open access)

Manufacturing Ultra-Precision Meso-scale Products by Coining

A method for replicating ultra-precision, meso-scale features onto a near-net-shape metallic blank has been demonstrated. The 'coining' technology can be used to imprint a wide range of features and/or profiles into two opposing surfaces. The instrumented system provides the ability to measure and control the product thickness and total thickness variation (TTV). The coining mechanism relies on kinematic principles to accurately and efficiently produce ultra-precision work pieces without the production of by products such as machining chips, or grinding swarf while preserving surface finish, material structure and overall form. Coining has been developed as a niche process for manufacturing difficult to machine, millimeter size components made from materials that may present hazardous conditions. In the case described in this paper a refractory metal part, tantalum (Ta) was produced with 4 {micro}m peak to valley 50 {micro}m special wavelength sine wave coined into the surface of 50 {micro}m blank. This technique shows promise for use on ductile materials that cannot be precision machined with conventional single crystal diamond tooling and/or has strict requirements on subsurface damage, surface impurities and grain structure. As a production process, it can be used to reduce manufacturing costs where large numbers of ultra-precision, repetitive designs are …
Date: February 18, 2010
Creator: Seugling, R M; Davis, P J; Rickens, K; Osmer, J & Brinksmeier, E
Object Type: Article
System: The UNT Digital Library
Tune Evaluation From Phased BPM Turn-By-Turn Data (open access)

Tune Evaluation From Phased BPM Turn-By-Turn Data

In fast ramping synchrotrons like the Fermilab Booster the conventional methods of betatron tune evaluation from the turn-by-turn data may not work due to rapid changes of the tunes (sometimes in a course of a few dozens of turns) and a high level of noise. We propose a technique based on phasing of signals from a large number of BPMs which significantly increases the signal to noise ratio. Implementation of the method in the Fermilab Booster control system is described and some measurement results are presented.
Date: May 18, 2010
Creator: Alexahin, Y.; Gianfelice-Wendt, E. & Marsh, W.
Object Type: Article
System: The UNT Digital Library
A grazing incidence x-ray streak camera for ultrafast, single-shot measurements (open access)

A grazing incidence x-ray streak camera for ultrafast, single-shot measurements

An ultrafast x-ray streak camera has been realized using a grazing incidence reflection photocathode. X-rays are incident on a gold photocathode at a grazing angle of 20 degree and photoemitted electrons are focused by a large aperture magnetic solenoid lens. The streak camera has high quantum efficiency, 600fs temporal resolution, and 6mm imaging length in the spectral direction. Its single shot capability eliminates temporal smearing due to sweep jitter, and allows recording of the ultrafast dynamics of samples that undergo non-reversible changes.
Date: February 18, 2010
Creator: Feng, Jun; Engelhorn, K.; Cho, B.I.; Lee, H. J.; Greaves, M.; Weber, C. P. et al.
Object Type: Article
System: The UNT Digital Library
PEM Degradation Investigation Final Technical Report (open access)

PEM Degradation Investigation Final Technical Report

This project conducted fundamental studies of PEM MEA degradation. Insights gained from these studies were disseminated to assist MEA manufacturers in understanding degradation mechanisms and work towards DOE 2010 fuel cell durability targets.
Date: October 18, 2010
Creator: Stevenson, Dan & Spangler, Lee H
Object Type: Report
System: The UNT Digital Library
Tandem Differential Mobility Analyzer/Aerodynamic Particle Sizer (APS) Handbook (open access)

Tandem Differential Mobility Analyzer/Aerodynamic Particle Sizer (APS) Handbook

The tandem differential mobility analyzer (TDMA) is a single instrument that cycles through a series of complementary measurements of the physical properties of size-resolved submicron particles. In 2008, the TDMA was augmented through the addition of an aerodynamic particle sizer (APS), which extends the upper limit of the measured size distribution into the supermicron range. These two instruments are operated in parallel, but because they are controlled by a common computer and because the size distributions measured by the two are integrated in the produced datastreams, they are described together here. Throughout the day, the TDMA sequentially measures submicron aerosol size distributions and size-resolved hygroscopic growth distributions. More specifically, the instrument is operated as a scanning DMA to measure size distributions and as a TDMA to measure size-resolved hygroscopicity. A typical measurement sequence requires roughly 45 minutes. Each morning additional measurements are made of the relative humidity (RH) dependent hygroscopicity and temperature-dependent volatility of size-resolved particles. When the outside temperature and RH are within acceptable ranges, the hydration state of size-resolved particles is also characterized. The measured aerosol distributions complement the array of aerosol instruments in the Aerosol Observing System (AOS) and provide additional details of the light-scattering and cloud-nucleating …
Date: June 18, 2010
Creator: Collins, D.
Object Type: Report
System: The UNT Digital Library
Optimization of Hydroacoustic Equipment Deployments at Lookout Point and Cougar Dams, Willamette Valley Project, 2010 (open access)

Optimization of Hydroacoustic Equipment Deployments at Lookout Point and Cougar Dams, Willamette Valley Project, 2010

The goal of the study was to optimize performance of the fixed-location hydroacoustic systems at Lookout Point Dam (LOP) and the acoustic imaging system at Cougar Dam (CGR) by determining deployment and data acquisition methods that minimized structural, electrical, and acoustic interference. The general approach was a multi-step process from mount design to final system configuration. The optimization effort resulted in successful deployments of hydroacoustic equipment at LOP and CGR.
Date: August 18, 2010
Creator: Johnson, Gary E.; Khan, Fenton; Ploskey, Gene R.; Hughes, James S. & Fischer, Eric S.
Object Type: Report
System: The UNT Digital Library
An Analysis of the NEXAFS Spectra of a molecular crystal: alpha-Glycine (open access)

An Analysis of the NEXAFS Spectra of a molecular crystal: alpha-Glycine

The nitrogen K-edge Near Edge X-ray Absorption Fine Structure (NEXAFS) spectrum of alpha-crystalline glycine has been calculated for temperatures ranging from 0 K to 450 K. Significant temperature dependent spectral changes are predicted. The calculated room temperature spectrum is in good agreement with experiment. At high temperatures, molecular motions strongly influence the spectrum, as any unique spectrum from an individual instantaneous configuration does not resemble the experimental result or the average calculated spectrum; complex coupled motions in this prototypical molecular crystal underlie the observed spectral changes.
Date: June 18, 2010
Creator: Schwartz, Craig P.; Saykally, Richard J. & Prendergast, David
Object Type: Article
System: The UNT Digital Library
Analytical Data Report for Sediment Samples Collected From 200 BP 5 OU, C5860 (299-E29-545) K-Well (open access)

Analytical Data Report for Sediment Samples Collected From 200 BP 5 OU, C5860 (299-E29-545) K-Well

This is an analytical data report for sediments received fro BP 5 K Well. This report is prepared for CHPRC
Date: June 18, 2010
Creator: Lindberg, Michael J.
Object Type: Report
System: The UNT Digital Library
Hanford Site Tank 241-C-108 Residual Waste Contaminant Release Models and Supporting Data (open access)

Hanford Site Tank 241-C-108 Residual Waste Contaminant Release Models and Supporting Data

This report presents the results of laboratory characterization, testing, and analysis for a composite sample (designated 20578) of residual waste collected from single-shell tank C-108 during the waste retrieval process after modified sluicing. These studies were completed to characterize concentration and form of contaminant of interest in the residual waste; assess the leachability of contaminants from the solids; and develop release models for contaminants of interest. Because modified sluicing did not achieve 99% removal of the waste, it is expected that additional retrieval processing will take place. As a result, the sample analyzed here is not expected to represent final retrieval sample.
Date: June 18, 2010
Creator: Cantrell, Kirk J.; Krupka, Kenneth M.; Geiszler, Keith N.; Arey, Bruce W. & Schaef, Herbert T.
Object Type: Report
System: The UNT Digital Library
The National Nanotechnology Initiative: Overview, Reauthorization, and Appropriations Issues (open access)

The National Nanotechnology Initiative: Overview, Reauthorization, and Appropriations Issues

This report provides an overview of nanotechnology, the National Nanotechnology Initiative, possible reauthorization of the 21st Century Nanotechnology Research and Development Act of 2003 (P.L. 108-153), and appropriations issues.
Date: March 18, 2010
Creator: Sargent, John F., Jr.
Object Type: Report
System: The UNT Digital Library
Pipeline Safety and Security: Federal Programs (open access)

Pipeline Safety and Security: Federal Programs

This report discusses congressional interest in securing the nation's pipelines. Nearly half a million miles of oil and natural gas transmission pipeline crisscross the United States. While an efficient and fundamentally safe means of transport, many pipelines carry hazardous materials with the potential to cause public injury and environmental damage.
Date: February 18, 2010
Creator: Parfomak, Paul W.
Object Type: Report
System: The UNT Digital Library
America COMPETES Reauthorization Act of 2010 (H.R. 5116) and the America COMPETES Act (P.L. 110-69): Selected Policy Issues (open access)

America COMPETES Reauthorization Act of 2010 (H.R. 5116) and the America COMPETES Act (P.L. 110-69): Selected Policy Issues

This report provides background information on P.L. 110-69 and H.R. 5116 and analyzes four policy issues addressed by both measures: (1) STEM Education, (2) Federal Research Programs and Activities, (3) Broadening Participation, and (4) Funding. It also discusses selected policy concerns identified in the debate about U.S. competitiveness and describes how H.R. 5116 responds to those concerns. It contains a description of federal multi-agency research and development initiatives that are included in H.R. 5116.
Date: May 18, 2010
Creator: Gonzalez, Heather B.; Sargent, John F., Jr. & Moloney Figliola, Patricia
Object Type: Report
System: The UNT Digital Library
The Jurisprudence of Justice John Paul Stevens: The Constitutionality of Congressional Term Limits and the Presidential Line Item Veto (open access)

The Jurisprudence of Justice John Paul Stevens: The Constitutionality of Congressional Term Limits and the Presidential Line Item Veto

While the Supreme Court seems unlikely to address the constitutionality of term limits or the line-item veto in the future, Justice Stevens's conclusion that the absence of constitutional provisions expressly authorizing the exercise of certain powers constitutes a denial of these powers seems likely to influence the Court in the future, particularly in cases involving what Justice Kennedy and others have characterized as "horizontal" or "vertical" separation of powers.
Date: May 18, 2010
Creator: Manuel, Kate M.
Object Type: Report
System: The UNT Digital Library
Tanzania: Background and Current Conditions (open access)

Tanzania: Background and Current Conditions

This report discusses the current political climate in Tanzania, an important U.S. ally in Africa. The report also provides some general background information.
Date: May 18, 2010
Creator: Dagne, Ted
Object Type: Report
System: The UNT Digital Library
Navy Littoral Combat Ship (LCS) Program: Background, Issues, and Options for Congress (open access)

Navy Littoral Combat Ship (LCS) Program: Background, Issues, and Options for Congress

This report discusses the Navy's plans regarding the Littoral Combat Ship (LCS). The LCS is a relatively inexpensive Navy surface combatant equipped with modular "plug-and-fight" mission packages. The Navy wants to field a force of 55 LCSs.
Date: February 18, 2010
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library