2-D Imaging of Electron Temperature in Tokamak Plasmas (open access)

2-D Imaging of Electron Temperature in Tokamak Plasmas

By taking advantage of recent developments in millimeter wave imaging technology, an Electron Cyclotron Emission Imaging (ECEI) instrument, capable of simultaneously measuring 128 channels of localized electron temperature over a 2-D map in the poloidal plane, has been developed for the TEXTOR tokamak. Data from the new instrument, detailing the MHD activity associated with a sawtooth crash, is presented.
Date: July 8, 2004
Creator: Munsat, T.; Mazzucato, E.; Park, H.; Domier, C. W.; Johnson, M.; Luhmann, N. C. Jr. et al.
System: The UNT Digital Library
40 Years of Discovery (open access)

40 Years of Discovery

History is most interesting when seen through the eyes of those who lived it. In this 40th anniversary retrospective of bioscience research at Lawrence Livermore National Laboratory, we've asked 19 scientists to share their personal recollections about a major accomplishment in the program's history. We have not tried to create a comprehensive or seamless story. Rather, we've attempted to capture the perspectives of key individuals, each of whom worked on a research program that met significant milestones. We have focused particularly on programs and accomplishments that have shaped the current Biology and Biotechnology Research Program (BBRP). In addition, we have included a timeline of biosciences at LLNL, a history of the directorate that appeared in the Laboratory's magazine, ''Science & Technology Review'', in 2002, and a list of bioscience-related articles that have appeared over the years in ''Science & Technology Review and its predecessor, Energy & Technology Review''. The landscape of biological science today is stunningly different from 40 years ago. When LLNL bioscience began in 1963, we knew about the structure of DNA and that it was the carrier of genetic information. However, it would be another year before scientists would understand how DNA codes for the production of …
Date: July 8, 2003
Creator: Heller, Arnie; Henke, Amy; Weinstein, Bert & Thomas, Cindy
System: The UNT Digital Library
Advanced turbine systems program conceptual design and product development. Quarterly report, February, 1996--April, 1996 (open access)

Advanced turbine systems program conceptual design and product development. Quarterly report, February, 1996--April, 1996

This paper describes the design and testing of critical gas turbine components. Development of catalytic combustors and diagnostic equipment is included.
Date: July 8, 1996
Creator: unknown
System: The UNT Digital Library
Air Kerma Calibration Factors and kch Values for PTW Soft X-ray, NACP and Roos Ionization Chambers at Very Low X-ray Energies (0.035 mm - 1.0 mm Al HVL) (open access)

Air Kerma Calibration Factors and kch Values for PTW Soft X-ray, NACP and Roos Ionization Chambers at Very Low X-ray Energies (0.035 mm - 1.0 mm Al HVL)

Several national and international protocols have been established for the dosimetry of x-ray beams used in radiotherapy. For the very low energy x-rays (0.035mm-1.0 mm Al HVL) only two codes are available: the UK IPEMB Code of Practice and the German standard, DIN 6809 Part 4. The measurement of very low energy x-ray beams is normally performed with parallel plate ionization chambers calibrated at a standards laboratory and characterized by an air kerma calibration factor N{sub k}. According to the IPEMB Code of Practice the absorbed dose in the user's beam should be determined by taking measurements with the parallel plate chamber positioned such that its entrance window is at the surface of a full-scatter water equivalent phantom. The absorbed dose to water can then be determined using an equation which includes a factor, k{sub ch}, which accounts for the change in response of the ionization chamber between the calibration in air and measurement at the surface of the phantom. N{sub k} and k{sub ch} values for the PTW soft X-ray, NACP and Roos ionization chambers are reported. It was found that k{sub ch} values varied from about 1.01 to 1.08 depending on the chamber, beam quality and phantom material. …
Date: July 8, 1999
Creator: Ipe, Nisy E.
System: The UNT Digital Library
AISI/DOE Technology Roadmap Program: Development of Appropriate Resistance Spot Welding Practice for Transformation-Hardened Steels (open access)

AISI/DOE Technology Roadmap Program: Development of Appropriate Resistance Spot Welding Practice for Transformation-Hardened Steels

This report describes work accomplished in the project, titled ''Development of Appropriate Resistance Spot Welding Practice for Transformation-Hardened Steels.'' The Phase 1 of the program involved development of in-situ temper diagrams for two gauges of representative dual-phase and martensitic grades of steels. The results showed that tempering is an effective way of reducing hold-time sensitivity (HTS) in hardenable high-strength sheet steels. In Phase 2, post-weld cooling rate techniques, incorporating tempering, were evaluated to reduce HTS for the same four steels. Three alternative methods, viz., post-heating, downsloping, and spike tempering, for HTS reduction were investigated. Downsloping was selected for detailed additional study, as it appeared to be the most promising of the cooling rate control methods. The downsloping maps for each of the candidate steels were used to locate the conditions necessary for the peak response. Three specific downslope conditions (at a fix ed final current for each material, timed for a zero-, medium-, and full-softening response) were chosen for further metallurgical and mechanical testing. Representative samples, were inspected metallographically, examining both local hardness variations and microstructures. The resulting downslope diagrams were found to consist largely of a C-curve. The softening observed in these curves, however, was not supported by subsequent …
Date: July 8, 2002
Creator: Chuko, Wayne & Gould, Jerry
System: The UNT Digital Library
Annual Report for Gravity Collection Lysimeter Monitoring in ERDF Cells 5, 6, 7, an 8, CY 2009 (open access)

Annual Report for Gravity Collection Lysimeter Monitoring in ERDF Cells 5, 6, 7, an 8, CY 2009

The purpose of this annual report is to evaluate the conditions and identify trends to develop Hanford Site specific data on the performance of the lysimeter systems related to the vadose zone monitoring and potential future use of lysimeter systems.
Date: July 8, 2010
Creator: R.L. Weiss, B.L. Lawrence
System: The UNT Digital Library
An Application of Trapped-Air Analysis to Large Complex High-Pressure Magnesium Casting (open access)

An Application of Trapped-Air Analysis to Large Complex High-Pressure Magnesium Casting

The usual method for simulating die-castings consists of a solidification analysis of the casting process - a computer calculation of heat transfer between the casting and the die components. The use of cyclic simulations, coupled with the geometric accuracy of the finite element method, has advanced this procedure to the point where it is routinely used for reliable prediction of shrinkage defects in die-castings. Filling analysis is also routinely used to get a glimpse of cavity filling and ensures that overflows are at their most effective location. When coupled with heat transfer, a filling analysis is also very effective in demonstrating the effects of heat loss in the fluid and how it consequentially can negatively affect filling.
Date: July 8, 2004
Creator: Prindiville, J.; Lee, S. & Gokhale, A.
System: The UNT Digital Library
Area Monitoring Dosimeter Program for the Pacific Northwest National Laboratory: Results for CY 2001 (open access)

Area Monitoring Dosimeter Program for the Pacific Northwest National Laboratory: Results for CY 2001

Pacific Northwest National Laboratory (PNNL) established an area monitoring dosimeter program in accordance with Article 514 of the U.S. Department of Energy (DOE) Radiological Control Manual (RCM) in January 1993. This program is to minimize the number of areas requiring issuance of personnel dosimeters and to demonstrate that doses outside Radiological Buffer Areas are negligible. In accordance with 10 CFR Part 835.402 (a) (1)-(4) and Article 511.1 of the PNNL Radiological Control Program Description, personnel dosimetry shall be provided to 1) radiological workers who are likely to receive at least 100 mrem annually, and 2) declared pregnant workers, minors, and members of the public who are likely to receive at least 50 mrem annually. Program results for calendar years 1993-2001 confirm that personnel dosimetry is not needed for individuals located in areas monitored by the program.
Date: July 8, 2002
Creator: Bivins, Steven R. & Stoetzel, Gregory A.
System: The UNT Digital Library
Assessment of Energy Savings Potential from the Use of Demand Control Ventilation Systems in General Office Spaces in California (open access)

Assessment of Energy Savings Potential from the Use of Demand Control Ventilation Systems in General Office Spaces in California

Demand controlled ventilation (DCV) was evaluated for general office spaces in California. A medium size office building meeting the prescriptive requirements of the 2008 California building energy efficiency standards (CEC 2008) was assumed in the building energy simulations performed with the EnergyPlus program to calculate the DCV energy savings potential in five typical California climates. Three design occupancy densities and two minimum ventilation rates were used as model inputs to cover a broader range of design variations. The assumed values of minimum ventilation rates in offices without DCV, based on two different measurement methods, were 81 and 28 cfm per occupant. These rates are based on the co-author's unpublished analyses of data from EPA's survey of 100 U.S. office buildings. These minimum ventilation rates exceed the 15 to 20 cfm per person required in most ventilation standards for offices. The cost effectiveness of applying DCV in general office spaces was estimated via a life cycle cost analyses that considered system costs and energy cost reductions. The results of the energy modeling indicate that the energy savings potential of DCV is largest in the desert area of California (climate zone 14), followed by Mountains (climate zone 16), Central Valley (climate zone …
Date: July 8, 2009
Creator: Hong, Tianzhen & Fisk, William J.
System: The UNT Digital Library
Assessment of the effects of microbially influenced degradation on a massive concrete structure. Final report, Report 5 (open access)

Assessment of the effects of microbially influenced degradation on a massive concrete structure. Final report, Report 5

There is a need to estimate the effect of environmental conditions on construction materials to be used in the repository at Yucca Mountain. Previous reports from this project have demonstrated that it is important to develop an understanding of microbially influenced degradation (MID) development and its influence on massive concrete structures. Further, it has been shown that the most effective way to obtain quantitative data on the effects of MID on the structural integrity of repository concrete is to study manmade, analog structures known to be susceptible to MID. The cooling tower shell located at the Ohaaki Power Station near Wairakei, New Zealand is such a structure.
Date: July 8, 1995
Creator: Rogers, R.D.
System: The UNT Digital Library
AStudy of the Relationship of Geological Formation to the Norm. (open access)

AStudy of the Relationship of Geological Formation to the Norm.

Naturally Occurring Radioactive Materials (NORM) is a common and costly contaminant of produced waters associated with natural gas production and exploration. One way of combating this problem is by identifying the problem beforehand. Our approach to this problem involves development of NORM prediction capabilities based on the geological environment. During the eleventh quarter of this project, emphasis again remained on two major tasks; identifying new sampling sites and seeking approval for final project revisions. In light of the delays experienced, the project has been granted a one year extension, and a revision is currently under review.
Date: July 8, 1997
Creator: Bursh, T. P. & Chriss, Derald
System: The UNT Digital Library
Automated solar panel assembly line. LSA task: production processes and equipment. Quarterly report No. 2 (open access)

Automated solar panel assembly line. LSA task: production processes and equipment. Quarterly report No. 2

The objective of this program is to design, fabricate and demonstrate an automated solar cell module production line with the ultimate goal of reducing module assembly costs. During this reporting period a redesign of the SCAP soldering mechanism was effected due to temperature/friction problems encountered. The in-line cleaning system was designed and ordered and the Mular backbone attachment mechanism was assembled. The SPLP production prototype was fabricated and operated. Two hand-assembled versions of the automated module design completed 750 thermal cycles. Albuquerque Laboratory, Ardev Inc., is under subcontract to develop the soldering equipment on this program. The lamination development is being done by ARCO Solar, Inc.
Date: July 8, 1979
Creator: Somberg, H.
System: The UNT Digital Library
Background radiation in the SLC ir from collimators and tune-up dumps in the ARCS (open access)

Background radiation in the SLC ir from collimators and tune-up dumps in the ARCS

There are various beam intercepting devices between the interaction point and the beam dumps of the SLC. Of these, the adjustable collimators, a fixed collimator, and the tune-up dumps are expected to intercept enough of the beam to warrant calculating the fluxes inside the interaction hall from them. The fluences of neutrons and photons in the interaction hall from these sources. Whether the beam has passed the interaction point or not is considered important in choosing a source term, primarily for photons. Neutron calculations are done only for giant resonance neutrons. (LEW)
Date: July 8, 1986
Creator: Jenkins, T.M.
System: The UNT Digital Library
Calibration of thin film EMP sensors by AFWL Coaxial Chamber (open access)

Calibration of thin film EMP sensors by AFWL Coaxial Chamber

Preliminary EMP calibration data on magnetic thin film current sensors has been obtained. The Air Force Weapon Lab's Coaxial Chamber was used as the EMP standard and a current pulse width of 40 ns was used. It was found that the sensitivity of the sensors can be increased by controlling the width of the 90/sup 0/ wall strip and that the current scales for the sensors were linear. The results strongly suggest that the dimensions of the sensors can be varied to meet different measurement requirements.
Date: July 8, 1976
Creator: Hsieh, E. J.; Vindelov, K. E.; Brown, T. G. & Miller, D. E.
System: The UNT Digital Library
Carbon Tetrachloride and Chloroform Partition Coefficients Derived from Aqueous Desorption of Contaminated Hanford Sediments (open access)

Carbon Tetrachloride and Chloroform Partition Coefficients Derived from Aqueous Desorption of Contaminated Hanford Sediments

Researchers at PNNL determined CCl4 and CHCl3 groundwater/sediment partition coefficients (Kd values) for contaminated aquifer sediments collected from borehole C3246 (299-W15-46) located in the 200 West Area adjacent to the Z-9 trench. Having realistic values for this parameter is critical to predict future movement of CCl4 in groundwater from the 200 West Area.
Date: July 8, 2005
Creator: Riley, Robert G.; Sklarew, Debbie S.; Brown, Christopher F.; Gent, Philip M.; Szecsody, Jim E.; Mitroshkov, Alexandre V. et al.
System: The UNT Digital Library
CAT Guide and Beamline Directory. A key to APS Collaborative Access Teams (open access)

CAT Guide and Beamline Directory. A key to APS Collaborative Access Teams

The Advanced Photon Source (APS), a national user facility for synchrotrons radiation research, is located at Argonne National Laboratory, approximately 25 miles southwest of Chicago, Illinois. The APS is considered a third-generation synchrotrons radiation facility (specifically designed to accommodate insertion devices to serve as radiation sources) and is one of three such facilities in the world. Currently, it is the most brilliant source in the United States for research in such diverse fields as biology, medicine, materials science, chemistry, geology, agriculture and soil science, physics, and manufacturing technology. Researchers use the APS either as members of Collaborative Access Teams (CATS) or as Independent Investigators (IIs). CATS are responsible for designing, building, and operating beamlines in one or more sectors, each sector consisting of an insertion-device (ID) beamline and a bending-magnet (BM) beamline. Each beamline is designed to accommodate a specific type of research program(s) and is optimized accordingly. CAT members are entitled to use 75% of the available beam time to pursue CAT research goals. The remaining 25% of the available beam time must be made available to IIs. This document was written to help prospective IIs determine which beamlines are suitable for their specific experiments.
Date: July 8, 1999
Creator: unknown
System: The UNT Digital Library
Characteristics of A-150 plastic-equivalent gas in A-150 plastic ionization chambers for p(66)Be(49) neutrons (open access)

Characteristics of A-150 plastic-equivalent gas in A-150 plastic ionization chambers for p(66)Be(49) neutrons

The evaluation of a gas mixture having an atomic composition similar to that of A-150 TE-plastic has been extended to a high energy neutron therapy beam. A-150 gas, air and methane-based TE gas were each flowed through A-150 plastic-walled ion chambers of different sizes and irradiated with p(66)Be(49) neutrons. A tentative value for anti W(A-150) of 27.3 +- 0.5 J C/sup -1/ was derived for this beam. The anti W value of the A-150 gas mixture is compared to those of methane-based TE gas and of air for the p(66)Be(49) neutron beam as well as to corresponding values found in similar experiments using 14.8 MeV monoenergetic neutrons. 17 references, 3 figures, 3 tables.
Date: July 8, 1982
Creator: Awschalom, M.; Rosenberg, I.; Ten Haken, R. K.; Pearson, D. W.; Attix, F. H. & DeLuca, P. M.
System: The UNT Digital Library
Characterization of Defense Waste Processing Facility (DWPF) Glass and Deposit Samples from Melter No.2 (open access)

Characterization of Defense Waste Processing Facility (DWPF) Glass and Deposit Samples from Melter No.2

The Defense Waste Processing Facility (DWPF) Engineering requested characterization of three glass samples that were taken from Melter number 2 after the waste loading had been increased, e.g. after the new quasicrystalline liquidus model had been implemented and after DWPF switched from processing with Frit 200 to Frit 320. These samples were taken after DWPF observed very rapid buildup of deposits in the upper pour spout bore and on the pour spout insert while processing the high waste loading (approximate 38 wt percent feedstock). Rapid deposition in these locations had not occurred prior to this and, in turn, stopped after waste loading decreased. These samples were evaluated at SRTC using various analytical techniques for potential impacts on pouring problems recently experienced by the DWPF.
Date: July 8, 2004
Creator: Jantzen, Carol M.; Cozzi, A. D. & Bibler, N. E.
System: The UNT Digital Library
Circulation in a Short Cylindrical Couette System (open access)

Circulation in a Short Cylindrical Couette System

In preparation for an experimental study of magnetorotational instability (MRI) in liquid metal, we explore Couette flows having height comparable to the gap between cylinders, centrifugally stable rotation, and high Reynolds number. Experiments in water are compared with numerical simulations. The flow is very different from that of an ideal, infinitely long Couette system. Simulations show that endcaps co-rotating with the outer cylinder drive a strong poloidal circulation that redistributes angular momentum. Predicted toroidal flow profiles agree well with experimental measurements. Spin-down times scale with Reynolds number as expected for laminar Ekman circulation; extrapolation from two-dimensional simulations at Re less than or equal to 3200 agrees remarkably well with experiment at Re approximately equal to 106. This suggests that turbulence does not dominate the effective viscosity. Further detailed numerical studies reveal a strong radially inward flow near both endcaps. After turning vertically along the inner cylinder, these flows converge at the midplane and depart the boundary in a radial jet. To minimize this circulation in the MRI experiment, endcaps consisting of multiple, differentially rotating rings are proposed. Simulations predict that an adequate approximation to the ideal Couette profile can be obtained with a few rings.
Date: July 8, 2003
Creator: Kageyama, Akira; Ji, Hantao & Goodman, Jeremy
System: The UNT Digital Library
Classification of HTTP Attacks: A Study on the ECML/PKDD 2007 Discovery Challenge (open access)

Classification of HTTP Attacks: A Study on the ECML/PKDD 2007 Discovery Challenge

None
Date: July 8, 2009
Creator: Gallagher, B. & Eliassi-Rad, T.
System: The UNT Digital Library
Collective Thomson scattering energetic particle diagnostic in high performance tokamaks. Final report (open access)

Collective Thomson scattering energetic particle diagnostic in high performance tokamaks. Final report

This report summarizes the work performed under DOE grant DE-FG03-95ER54334. Lodestar was an active participant in the low power Collective Thomson Scattering (CTS) diagnostic experiment at TFTR in collaboration with MIT. A simple and effective fitting technique was developed to extract key parameters from the scattered data. Utilizing this new technique, the concept of lower hybrid resonance scattering was adapted for a feasibility study of a low/medium power collective scattering diagnostic for ITER. The implementation and the testing of such a technique for actual parameter extraction using TFTR data, however, was severely limited due to experimental and instrumentation complications. Based on the studies the authors have performed up to date, it is believed that a combination of non-physics related effects such as multiple wall reflection of incident signal and spectral impurity problem o the gyrotron can account for the anomalous signal strength. A collaborative effort with GA was initiated and a feasibility study of developing and implementing a collective thomson scattering (CTS) diagnostic for the detection of energetic particles at DIII-D was completed. Specifically, the process of selecting an optimum receiver location for the diagnostic is discussed in detailed. Results presented here include detailed signal to noise calculations and ray-tracing …
Date: July 8, 1997
Creator: Cheung, P. Y.; Aamodt, R. E. & Russell, D. A.
System: The UNT Digital Library
Comparison between the United States and United Kingdom Criticality Safety Personnel Training Program Guidance (open access)

Comparison between the United States and United Kingdom Criticality Safety Personnel Training Program Guidance

None
Date: July 8, 2013
Creator: Wysong, A R
System: The UNT Digital Library
Compilation of carbon-14 data (open access)

Compilation of carbon-14 data

A review and critical analysis was made of the original sources of carbon-14 in the graphite moderator and reflector zones of the eight Hanford production reactors, the present physical and chemical state of the carbon-14, pathways (other than direct combustion) by which the carbon-14 could be released to the biosphere, and the maximum rate at which it might be released under circumstances which idealistically favor the release. Areas of uncertainty are noted and recommendations are made for obtaining additional data in three areas: (1) release rate of carbon-14 from irradiated graphite saturated with aerated water; (2) characterization of carbon-14 deposited outside the moderator and reflector zones; and (3) corrosion/release rate of carbon-14 from irradiated steel and aluminum alloys.
Date: July 8, 1985
Creator: Paasch, R. A.
System: The UNT Digital Library
Computational Fluid Dynamics Modeling of the John Day Dam Tailrace (open access)

Computational Fluid Dynamics Modeling of the John Day Dam Tailrace

US Army Corps of Engineers - Portland District required that a two-dimensional (2D) depth-averaged and a three-dimensional (3D) free-surface numerical models to be developed and validated for the John Day tailrace. These models were used to assess potential impact of a select group of structural and operational alternatives to tailrace flows aimed at improving fish survival at John Day Dam. The 2D model was used for the initial assessment of the alternatives in conjunction with a reduced-scale physical model of the John Day Project. A finer resolution 3D model was used to more accurately model the details of flow in the stilling basin and near-project tailrace hydraulics. Three-dimensional model results were used as input to the Pacific Northwest National Laboratory particle tracking software, and particle paths and times to pass a downstream cross section were used to assess the relative differences in travel times resulting from project operations and structural scenarios for multiple total river flows. Streamlines and neutrally-buoyant particles were seeded in all turbine and spill bays with flows. For a Total River of 250 kcfs running with the Fish Passage Plan spill pattern and a spillwall, the mean residence times for all particles were little changed; however the …
Date: July 8, 2010
Creator: Rakowski, Cynthia L.; Perkins, William A.; Richmond, Marshall C. & Serkowski, John A.
System: The UNT Digital Library