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Sample records for dual axis radiographic

  1. Dual Axis Radiographic Hydrodynamic Test Facility | National...

    National Nuclear Security Administration (NNSA)

    Dual Axis Radiographic Hydrodynamic Test Facility An integral part of the national ... radiographic images of the imploding test object, in which materials are moving at ...

  2. DARHT: Dual-Axis Radiographic Hydrodynamic Test Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    DARHT: Dual-Axis Radiographic Hydrodynamic Test Facility DARHT: Dual-Axis Radiographic Hydrodynamic Test Facility DARHT, supports a critical component of LANL's primary mission: to...

  3. Dual Axis Radiographic Hydrodynamic Test Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    DARHT DARHT Facility: A critical component of stockpile stewardship A new research frontier awaits! Our door is open and we thrive on mutually beneficial partnerships, collaborations that drive innovations and new technologies. April 12, 2012 Dominic Tafoya and Dave Honaberger prepare a refurbished DARHT (Dual Axis Radiographic Hydrotest Facility) 2nd axis accelerator cell for magnetic axis alignment measurements. Contact Group Leader Terry Priestley (505) 665-1330 Email Deputy Group Leader Tim

  4. DARHT: Dual-Axis Radiographic Hydrodynamic Test Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    DARHT: Dual-Axis Radiographic Hydrodynamic Test Facility DARHT: Dual-Axis Radiographic Hydrodynamic Test Facility DARHT, supports a critical component of LANL's primary mission: to ensure the safety, security, and effectiveness of nuclear weapons in our nation's stockpile. Los Alamos scientists built DARHT, the world's most powerful x-ray machine, to analyze mockups of nuclear weapons. At the Los Alamos National Laboratory (LANL), the Dual-Axis Radiographic Hydrodynamic Test Facility, or DARHT,

  5. EIS-0228: Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility

    Broader source: Energy.gov [DOE]

    This EIS evaluates the potential environmental impact of a proposal to construct and operate the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory (LANL)...

  6. Dual Axis Radiographic Hydrodynamic Test | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration Dual Axis Radiographic Hydrodynamic Test NNSA releases Stockpile Stewardship Program quarterly experiments summary WASHIGTON, DC. - The National Nuclear Security Administration today released its current quarterly summary of experiments conducted as part of its science-based Stockpile Stewardship Program. The experiments carried out within the program are used in combination with complex computational models

  7. Dual Axis Radiographic Hydrodynamic Test Facility | National Nuclear

    National Nuclear Security Administration (NNSA)

    Security Administration | (NNSA) Dual Axis Radiographic Hydrodynamic Test Facility An integral part of the national hydrotest program, the DARHT is the world's most powerful x-ray machine. DARHT consists of two electron accelerators oriented at right angles to one another. Each accelerator creates a powerful electron beam that is focused onto a metal target which converts the kinetic energy of the electron beam into high energy x or gamma-rays. The x-ray dose from one DARHT accelerator is

  8. Dual Axis Radiographic Hydrodynamic Test Facility mitigation action plan. Annual report for 1998

    SciTech Connect (OSTI)

    Haagenstad, T.

    1999-01-15

    This Mitigation Action Plan Annual Report (MAPAR) has been prepared as part of implementing the Dual Axis Radiographic Hydrodynamic Test Facility (DARHT) Mitigation Action Plan (MAP) to protect workers, soils, water, and biotic and cultural resources in and around the facility.

  9. Dual axis radiographic hydrodynamic test facility. Final environmental impact statement, Volume 2: Public comments and responses

    SciTech Connect (OSTI)

    1995-08-01

    On May 12, 1995, the U.S. Department of Energy (DOE) issued the draft Dual Axis Radiographic Hydrodynamic Test Facility Environmental Impact Statement (DARHT EIS) for review by the State of New Mexico, Indian Tribes, local governments, other Federal agencies, and the general public. DOE invited comments on the accuracy and adequacy of the draft EIS and any other matters pertaining to their environmental reviews. The formal comment period ran for 45 days, to June 26, 1995, although DOE indicated that late comments would be considered to the extent possible. As part of the public comment process, DOE held two public hearings in Los Alamos and Santa Fe, New Mexico, on May 31 and June 1, 1995. In addition, DOE made the draft classified supplement to the DARHT EIS available for review by appropriately cleared individuals with a need to know the classified information. Reviewers of the classified material included the State of New Mexico, the U.S. Environmental Protection Agency, the Department of Defense, and certain Indian Tribes. Volume 2 of the final DARHT EIS contains three chapters. Chapter 1 includes a collective summary of the comments received and DOE`s response. Chapter 2 contains the full text of the public comments on the draft DARHT EIS received by DOE. Chapter 3 contains DOE`s responses to the public comments and an indication as to how the comments were considered in the final EIS.

  10. Dual Axis Radiographic Hydrodynamic Test Facility mitigation action plan. Annual report for 1997

    SciTech Connect (OSTI)

    Haagenstad, H.T.

    1998-01-15

    This Mitigation Action Plan Annual Report (MAPAR) has been prepared by the US Department of Energy (DOE) as part of implementing the Dual Axis Radiographic Hydrodynamic Test Facility (DARHT) Mitigation Action Plan (MAP). This MAPAR provides a status on specific DARHT facility design- and construction-related mitigation actions that have been initiated in order to fulfill DOE`s commitments under the DARHT MAP. The functions of the DARHT MAP are to (1) document potentially adverse environmental impacts of the Phased Containment Option delineated in the Final EIS, (2) identify commitments made in the Final EIS and ROD to mitigate those potential impacts, and (3) establish Action Plans to carry out each commitment (DOE 1996). The DARHT MAP is divided into eight sections. Sections 1--5 provide background information regarding the NEPA review of the DARHT project and an introduction to the associated MAP. Section 6 references the Mitigation Action Summary Table which summaries the potential impacts and mitigation measures; indicates whether the mitigation is design-, construction-, or operational-related; the organization responsible for the mitigation measure; and the projected or actual completion data for each mitigation measure. Sections 7 and 8 discuss the Mitigation Action Plan Annual Report and Tracking System commitment and the Potential Impacts, Commitments, and Action Plans respectively. Under Section 8, potential impacts are categorized into five areas of concern: General Environment, including impacts to air and water; Soils, especially impacts affecting soil loss and contamination; Biotic Resources, especially impacts affecting threatened and endangered species; Cultural/Paleontological Resources, especially impacts affecting the archeological site known as Nake`muu; and Human Health and Safety, especially impacts pertaining to noise and radiation. Each potential impact includes a brief statement of the nature of the impact and its cause(s). The commitment

  11. Static-stress analysis of dual-axis confinement vessel

    SciTech Connect (OSTI)

    Bultman, D.H.

    1992-11-01

    This study evaluates the static-pressure containment capability of a 6-ft-diameter, spherical vessel, made of HSLA-100 steel, to be used for high-explosive (HE) containment. The confinement vessel is designed for use with the Dual-Axis Radiographic Hydrotest Facility (DARHT) being developed at Los Alamos National Laboratory. Two sets of openings in the vessel are covered with x-ray transparent covers to allow radiographic imaging of an explosion as it occurs inside the vessel. The confinement vessel is analyzed as a pressure vessel based on the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, and the Welding Research Council Bulletin, WRC-107. Combined stresses resulting from internal pressure and external loads on nozzles are calculated and compared with the allowable stresses for HSLA-100 steel. Results confirm that the shell and nozzles of the confinement vessel are adequately designed to safely contain the maximum residual pressure of 1675 psi that would result from an HE charge of 24.2 kg detonated in a vacuum. Shell stresses at the shell-to-nozzle interface, produced from external loads on the nozzles, were less than 400 psi. The maximum combined stress resulting from the internal pressure plus external loads was 16,070 psi, which is less than half the allowable stress of 42,375 psi for HSLA-100 steel.

  12. Static-stress analysis of dual-axis safety vessel

    SciTech Connect (OSTI)

    Bultman, D.H.

    1992-11-01

    An 8-ft-diameter safety vessel, made of HSLA-100 steel, is evaluated to determine its ability to contain the quasi-static residual pressure from a high-explosive (HE) blast. The safety vessel is designed for use with the Dual-Axis Radiographic Hydrotest (DARHT) facility being developed at Los Alamos National Laboratory. A smaller confinement vessel fits inside the safety vessel and contains the actual explosion, and the safety vessel functions as a second layer of containment in the unlikely case of a confinement vessel leak. The safety vessel is analyzed as a pressure vessel based on the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, and the Welding Research Council Bulletin, WRC107. Combined stresses that result from internal pressure and external loads on nozzles are calculated and compared to the allowable stresses for HSLA-100 steel. Results confirm that the shell and nozzle components are adequately designed for a static pressure of 830 psi, plus the maximum expected external loads. Shell stresses at the shellto-nozzle interface, produced from external loads on the nozzles, were less than 700 psi. The maximum combined stress resulting from the internal pressure plus external loads was 17,384 psi, which is significantly less than the allowable stress of 42,375 psi for HSLA-100 steel.

  13. DARHT status and preparations for dual-axis hydrotesting (u)

    SciTech Connect (OSTI)

    Bowman, David W

    2010-01-01

    The status of the DARHT facility, including a history of events that have taken place since the end of the DARHT Second Axis Refurbishment Project, is discussed. Technical and operational enhancements that have been made will be addressed, and recent technical challenges, such as the RF noise in the kicker region, are discussed. Historical data on reliability of the second axis is discussed, as well as operational changes made to enhance reliability. In addition, the path forward for integrating the second axis into overall DARHT operations in preparation for a hydrotest is addressed. Timing integration tests are accompanied by a series of tests to evaluate neutron contamination and cross-axis scatter, with attempts being made to provide adequate shielding to minimize the effects of neutrons and cross-beam scatter. The discussion includes results of the testing performed to-date, and concludes with a discussion of the path forward for dual-axis hydrotesting at DARHT.

  14. Dual-Axis Resonance Testing of Wind Turbine Blades - Energy Innovation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Return to Search Dual-Axis Resonance Testing of Wind Turbine Blades National Renewable ... of time needed to fatigue test wind turbine blades.
    Dual-axis testing can ...

  15. AXIS: An instrument for imaging Compton radiographs using the Advanced Radiography Capability on the NIF

    SciTech Connect (OSTI)

    Hall, G. N. Izumi, N.; Tommasini, R.; Carpenter, A. C.; Palmer, N. E.; Zacharias, R.; Felker, B.; Holder, J. P.; Allen, F. V.; Bell, P. M.; Bradley, D.; Montesanti, R.; Landen, O. L.

    2014-11-15

    Compton radiography is an important diagnostic for Inertial Confinement Fusion (ICF), as it provides a means to measure the density and asymmetries of the DT fuel in an ICF capsule near the time of peak compression. The AXIS instrument (ARC (Advanced Radiography Capability) X-ray Imaging System) is a gated detector in development for the National Ignition Facility (NIF), and will initially be capable of recording two Compton radiographs during a single NIF shot. The principal reason for the development of AXIS is the requirement for significantly improved detection quantum efficiency (DQE) at high x-ray energies. AXIS will be the detector for Compton radiography driven by the ARC laser, which will be used to produce Bremsstrahlung X-ray backlighter sources over the range of 50 keV–200 keV for this purpose. It is expected that AXIS will be capable of recording these high-energy x-rays with a DQE several times greater than other X-ray cameras at NIF, as well as providing a much larger field of view of the imploded capsule. AXIS will therefore provide an image with larger signal-to-noise that will allow the density and distribution of the compressed DT fuel to be measured with significantly greater accuracy as ICF experiments are tuned for ignition.

  16. Dual-axis high-data-rate atom interferometer via cold ensemble exchange

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Journal Article: Dual-axis high-data-rate atom interferometer via cold ensemble exchange Citation Details In-Document Search Title: Dual-axis high-data-rate atom interferometer via cold ensemble exchange We demonstrate a dual-axis accelerometer and gyroscope atom interferometer, which can form the building blocks of a six-axis inertial measurement unit. By recapturing the atoms after the interferometer sequence, we maintain a large atom number at high data

  17. Measuring x-ray spectra of flash radiographic sources

    SciTech Connect (OSTI)

    Gehring, Amanda Elizabeth; Espy, Michelle A.; Haines, Todd Joseph; Mendez, Jacob; Moir, David C.; Sedillo, Robert; Shurter, Roger P.; Volegov, Petr Lvovich; Webb, Timothy J

    2015-11-02

    The x-ray spectra of flash radiographic sources is difficult to measure. The sources measured were Radiographic Integrated Test Stand-6 (370 rad at 1 m; 50 ns pulse) and Dual Axis Radiographic Hydrodynamic Test Facility (DARHT) (550 rad at 1 m; 50 ns pulse). Features of the Compton spectrometer are described, and spectra are shown. Additional slides present data on instrumental calibration.

  18. Dual axis translation apparatus and system for translating an optical beam and related method

    DOE Patents [OSTI]

    Cassidy, Kelly

    1991-01-01

    A dual axis translation device and system in accordance with this invention, for translating an optical beam along both an x-axis and a y-axis which are perpendicular to one another, has a beam directing means acting on said optical beam for directing the beam along a particular path transverse to said x and y axes. An arrangement supporting said beam directing means for movement in the x and y direction within a given plane is provided. The arrangement includes a first means for translating said beam directing means along the x-axis in said given plane in order to translate the beam along said x-axis. The arrangement comprises a second means for translating said beam directing means along the y-axis in said given plane in order to translate the beam along said y-axis.

  19. Dual-axis resonance testing of wind turbine blades

    SciTech Connect (OSTI)

    Hughes, Scott; Musial, Walter; White, Darris

    2014-01-07

    An apparatus (100) for fatigue testing test articles (104) including wind turbine blades. The apparatus (100) includes a test stand (110) that rigidly supports an end (106) of the test article (104). An actuator assembly (120) is attached to the test article (104) and is adapted for substantially concurrently imparting first and second forcing functions in first and second directions on the test article (104), with the first and second directions being perpendicular to a longitudinal axis. A controller (130) transmits first and second sets of displacement signals (160, 164) to the actuator assembly (120) at two resonant frequencies of the test system (104). The displacement signals (160, 164) initiate the actuator assembly (120) to impart the forcing loads to concurrently oscillate the test article (104) in the first and second directions. With turbine blades, the blades (104) are resonant tested concurrently for fatigue in the flapwise and edgewise directions.

  20. Sun-Relative Pointing for Dual-Axis Solar Trackers Employing Azimuth and Elevation Rotations

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Riley, Daniel; Hansen, Clifford W.

    2014-12-30

    Dual axis trackers employing azimuth and elevation rotations are common in the field of photovoltaic (PV) energy generation. Accurate sun-tracking algorithms are widely available. However, a steering algorithm has not been available to accurately point the tracker away from the sun such that a vector projection of the sun beam onto the tracker face falls along a desired path relative to the tracker face. We have developed an algorithm which produces the appropriate azimuth and elevation angles for a dual axis tracker when given the sun position, desired angle of incidence, and the desired projection of the sun beam ontomore » the tracker face. Development of this algorithm was inspired by the need to accurately steer a tracker to desired sun-relative positions in order to better characterize the electro-optical properties of PV and CPV modules.« less

  1. Sun-Relative Pointing for Dual-Axis Solar Trackers Employing Azimuth and Elevation Rotations

    SciTech Connect (OSTI)

    Riley, Daniel; Hansen, Clifford W.

    2014-12-30

    Dual axis trackers employing azimuth and elevation rotations are common in the field of photovoltaic (PV) energy generation. Accurate sun-tracking algorithms are widely available. However, a steering algorithm has not been available to accurately point the tracker away from the sun such that a vector projection of the sun beam onto the tracker face falls along a desired path relative to the tracker face. We have developed an algorithm which produces the appropriate azimuth and elevation angles for a dual axis tracker when given the sun position, desired angle of incidence, and the desired projection of the sun beam onto the tracker face. Development of this algorithm was inspired by the need to accurately steer a tracker to desired sun-relative positions in order to better characterize the electro-optical properties of PV and CPV modules.

  2. Tracking formulas and strategies for a receiver oriented dual-axis tracking toroidal heliostat

    SciTech Connect (OSTI)

    Guo, Minghuan; Wang, Zhifeng; Liang, Wenfeng; Zhang, Xiliang; Zang, Chuncheng; Lu, Zhenwu; Wei, Xiudong

    2010-06-15

    A 4 m x 4 m toroidal heliostat with receiver oriented dual-axis tracking, also called spinning-elevation tracking, was developed as an auxiliary heat source for a hydrogen production system. A series of spinning-elevation tracking formulas have been derived for this heliostat. This included basic tracking formulas, a formula for the elevation angle for heliostat with a mirror-pivot offset, and a more general formula for the biased elevation angle. This paper presents the new tracking formulas in detail and analyzes the accuracy of applying a simplifying approximation. The numerical results show these receiver oriented dual-axis tracking formula approximations are accurate to within 2.5 x 10{sup -6} m in image plane. Some practical tracking strategies are discussed briefly. Solar images from the toroidal heliostat at selected times are also presented. (author)

  3. Dual-axis high-data-rate atom interferometer via cold ensemble exchange

    SciTech Connect (OSTI)

    Rakholia, Akash V.; McGuinness, Hayden J.; Biedermann, Grant W.

    2014-11-24

    We demonstrate a dual-axis accelerometer and gyroscope atom interferometer, which can form the building blocks of a six-axis inertial measurement unit. By recapturing the atoms after the interferometer sequence, we maintain a large atom number at high data rates of 50 to 100 measurements per second. Two cold ensembles are formed in trap zones located a few centimeters apart and are launched toward one another. During their ballistic trajectory, they are interrogated with a stimulated Raman sequence, detected, and recaptured in the opposing trap zone. As a result, we achieve sensitivities at ?g/ ?Hz and ?rad/s/ ?Hz levels, making this a compelling prospect for expanding the use of atom interferometer inertial sensors beyond benign laboratory environments.

  4. Dual-axis high-data-rate atom interferometer via cold ensemble exchange

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rakholia, Akash V.; McGuinness, Hayden J.; Biedermann, Grant W.

    2014-11-24

    We demonstrate a dual-axis accelerometer and gyroscope atom interferometer, which can form the building blocks of a six-axis inertial measurement unit. By recapturing the atoms after the interferometer sequence, we maintain a large atom number at high data rates of 50 to 100 measurements per second. Two cold ensembles are formed in trap zones located a few centimeters apart and are launched toward one another. During their ballistic trajectory, they are interrogated with a stimulated Raman sequence, detected, and recaptured in the opposing trap zone. As a result, we achieve sensitivities at μg/ √Hz and μrad/s/ √Hz levels, making thismore » a compelling prospect for expanding the use of atom interferometer inertial sensors beyond benign laboratory environments.« less

  5. A lightweight high performance dual-axis gimbal for space applications

    SciTech Connect (OSTI)

    Pines, D.J.; Hakala, D.B.; Malueg, R.

    1995-05-05

    This paper describes the design, development and performance of a lightweight precision gimbal with dual-axis slew capability to be used in a closed-loop optical tracking system at Lawrence Livermore National Laboratory-LLNL. The motivation for the development of this gimbal originates from the need to acquire and accurately localize warm objects (T{approximately}500 K) in a cluttered background. The design of the gimbal is centered around meeting the following performance requirements: pointing accuracy with control < 35 {mu}rad-(1-{omega}); slew capability > 0.2 rad/sec; mechanical weight < 5 kg. These performance requirements are derived by attempting to track a single target from multiple satellites in low Earth orbit using a mid-wave infrared camera. Key components in the gimbal hardware that are essential to meeting the performance objectives include a nickel plated beryllium mirro, an accurate lightweight capacitive pickoff device for angular measurement about the elevation axis, a 16-bit coarse/fine resolver for angular measurement about the azimuth axis, a toroidally wound motor with low hysteresis for providing torque about the azimuth axis, and the selection of beryllium parts to insure high stiffness to weight ratios and more efficient thermal conductivity. Each of these elements are discussed in detail to illustrate the design trades performed to meet the tracking and slewing requirements demanded. Preliminary experimental results are also given for various commanded tracking maneuvers.

  6. Development of a MEMS dual-axis differential capacitance floating element shear stress sensor

    SciTech Connect (OSTI)

    Barnard, Casey; Griffin, Benjamin

    2015-09-01

    A single-axis MEMS wall shear stress sensor with differential capacitive transduction method is produced. Using a synchronous modulation and demodulation interface circuit, the system is capable of making real time measurements of both mean and fluctuating wall shear stress. A sensitivity of 3.44 mV/Pa is achieved, with linearity in response demonstrated up to testing limit of 2 Pa. Minimum detectable signals of 340 μPa at 100 Hz and 120 μPa at 1 kHz are indicated, with a resonance of 3.5 kHz. Multiple full scale wind tunnel tests are performed, producing spectral measurements of turbulent boundary layers in wind speeds ranging up to 0.5 Ma (18 Pa of mean wall shear stress). The compact packaging allows for minimally invasive installation, and has proven relatively robust over multiple testing events. Temperature sensitivity, likely due to poor CTE matching of packaged materials, is an ongoing concern being addressed. These successes are being directly leveraged into a development plan for a dual-axis wall shear stress sensor, capable of producing true vector estimates at the wall.

  7. Facilities | National Nuclear Security Administration | (NNSA...

    National Nuclear Security Administration (NNSA)

    Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility, Los Alamos National ... Dual Axis Radiographic Hydrodynamic Test Facility High Explosives Application ...

  8. DARHT Axis-I Diode Simulations II: Geometrical Scaling

    SciTech Connect (OSTI)

    Ekdahl, Carl A. Jr.

    2012-06-14

    Flash radiography of large hydrodynamic experiments driven by high explosives is a venerable diagnostic technique in use at many laboratories. Many of the largest hydrodynamic experiments study mockups of nuclear weapons, and are often called hydrotests for short. The dual-axis radiography for hydrodynamic testing (DARHT) facility uses two electron linear-induction accelerators (LIA) to produce the radiographic source spots for perpendicular views of a hydrotest. The first of these LIAs produces a single pulse, with a fixed {approx}60-ns pulsewidth. The second axis LIA produces as many as four pulses within 1.6-{micro}s, with variable pulsewidths and separation. There are a wide variety of hydrotest geometries, each with a unique radiographic requirement, so there is a need to adjust the radiographic dose for the best images. This can be accomplished on the second axis by simply adjusting the pulsewidths, but is more problematic on the first axis. Changing the beam energy or introducing radiation attenuation also changes the spectrum, which is undesirable. Moreover, using radiation attenuation introduces significant blur, increasing the effective spot size. The dose can also be adjusted by changing the beam kinetic energy. This is a very sensitive method, because the dose scales as the {approx}2.8 power of the energy, but it would require retuning the accelerator. This leaves manipulating the beam current as the best means for adjusting the dose, and one way to do this is to change the size of the cathode. This method has been proposed, and is being tested. This article describes simulations undertaken to develop scaling laws for use as design tools in changing the Axis-1 beam current by changing the cathode size.

  9. Microsoft Word - Defense Science Quarterly 08-08.doc

    National Nuclear Security Administration (NNSA)

    6 Dual Axis Radiographic Hydrodynamics Test (DARHT) 2 nd Axis Completed and Put into ... Another big facility at LANL is the Dual Axis Radiographic Hydrodynamics Test (DARHT), and ...

  10. DOE/EIS-0380

    National Nuclear Security Administration (NNSA)

    1 2.1 Dual-Axis Radiographic Hydrodynamic Test Facility Mitigation Action Plan (Appendix ... II Dual Axis Radiographic Hydrodynamic Test Facility Mitigation Action Plan Annual ...

  11. Tuning the DARHT Axis-II linear induction accelerator focusing

    SciTech Connect (OSTI)

    Ekdahl, Carl A.

    2012-04-24

    Flash radiography of large hydrodynamic experiments driven by high explosives is a well-known diagnostic technique in use at many laboratories, and the Dual-Axis Radiography for Hydrodynamic Testing (DARHT) facility at Los Alamos produces flash radiographs of large hydrodynamic experiments. Two linear induction accelerators (LIAs) make the bremsstrahlung radiographic source spots for orthogonal views of each test. The 2-kA, 20-MeV Axis-I LIA creates a single 60-ns radiography pulse. The 1.7-kA, 16.5-MeV Axis-II LIA creates up to four radiography pulses by kicking them out of a longer pulse that has a 1.6-{mu}s flattop. The Axis-II injector, LIA, kicker, and downstream transport (DST) to the bremsstrahlung converter are described. Adjusting the magnetic focusing and steering elements to optimize the electron-beam transport through an LIA is often called 'tuning.' As in all high-current LIAs, the focusing field is designed to be as close to that of the ideal continuous solenoid as physically possible. In ideal continuous solenoidal transport a smoothly varying beam size can easily be found for which radial forces balance, and the beam is said to be 'matched' to the focusing field. A 'mismatched' beam exhibits unwanted oscillations in size, which are a source of free energy that contributes to emittance growth. This is undesirable, because in the absence of beam-target effects, the radiographic spot size is proportional to the emittance. Tuning the Axis-II LIA is done in two steps. First, the solenoidal focusing elements are set to values designed to provide a matched beam with little or no envelope oscillations, and little or no beam-breakup (BBU) instability growth. Then, steering elements are adjusted to minimize the motion of the centroid of a well-centered beam at the LIA exit. This article only describes the design of the tune for the focusing solenoids. The DARHT Axis-II LIA was required to be re-tuned after installing an accelerator cell to replace a failed

  12. RF generation in the DARHT Axis-II beam dump

    SciTech Connect (OSTI)

    Ekdahl, Carl A. Jr.

    2012-05-03

    We have occasionally observed radio-frequency (RF) electromagnetic signals in the downstream transport (DST) of the second axis linear induction accelerator (LIA) at the dual-axis radiographic hydrodynamic testing (DARHT) facility. We have identified and eliminated some of the sources by eliminating the offending cavities. However, we still observe strong RF in the range 1 GHz t0 2 GHz occurring late in the {approx}2-{micro}s pulse that can be excited or prevented by varying the downstream tune. The narrow frequency width (<0.5%) and near exponential growth at the dominant frequency is indicative of a beam-cavity interaction, and electro-magnetic simulations of cavity structure show a spectrum rich in resonances in the observed frequency range. However, the source of beam produced RF in the cavity resonance frequency range has not been identified, and it has been the subject of much speculation, ranging from beam-plasma or beam-ion instabilities to unstable cavity coupling.

  13. Diode magnetic-field influence on radiographic spot size

    SciTech Connect (OSTI)

    Ekdahl, Carl A. Jr.

    2012-09-04

    Flash radiography of hydrodynamic experiments driven by high explosives is a well-known diagnostic technique in use at many laboratories. The Dual-Axis Radiography for Hydrodynamic Testing (DARHT) facility at Los Alamos was developed for flash radiography of large hydrodynamic experiments. Two linear induction accelerators (LIAs) produce the bremsstrahlung radiographic source spots for orthogonal views of each experiment ('hydrotest'). The 2-kA, 20-MeV Axis-I LIA creates a single 60-ns radiography pulse. For time resolution of the hydrotest dynamics, the 1.7-kA, 16.5-MeV Axis-II LIA creates up to four radiography pulses by slicing them out of a longer pulse that has a 1.6-{micro}s flattop. Both axes now routinely produce radiographic source spot sizes having full-width at half-maximum (FWHM) less than 1 mm. To further improve on the radiographic resolution, one must consider the major factors influencing the spot size: (1) Beam convergence at the final focus; (2) Beam emittance; (3) Beam canonical angular momentum; (4) Beam-motion blur; and (5) Beam-target interactions. Beam emittance growth and motion in the accelerators have been addressed by careful tuning. Defocusing by beam-target interactions has been minimized through tuning of the final focus solenoid for optimum convergence and other means. Finally, the beam canonical angular momentum is minimized by using a 'shielded source' of electrons. An ideal shielded source creates the beam in a region where the axial magnetic field is zero, thus the canonical momentum zero, since the beam is born with no mechanical angular momentum. It then follows from Busch's conservation theorem that the canonical angular momentum is minimized at the target, at least in principal. In the DARHT accelerators, the axial magnetic field at the cathode is minmized by using a 'bucking coil' solenoid with reverse polarity to cancel out whatever solenoidal beam transport field exists there. This is imperfect in practice, because of

  14. Four Pulse Drive System for the Beam Induction Cells for DARHT Axis 2

    SciTech Connect (OSTI)

    Downing, J.; Carlson, R.; Melton, J.; Fockler, J.

    1999-06-28

    The proposed drive system allows for the generation of up to four (4) high-quality radiographic pulses along one line-of-sight, having arbitrary pulse spacing ({approximately}500 ns), using demonstrated technologies. This concept uses a four-pulse drive system to drive both a 16-MeV ensemble of 250-kV, 4-kA induction cells and a four-pulse, 4-MeV injector. The key to this approach lies in the method used to combine four pulses from different generators in a manner that does not compromise the voltage flatness requirement of {+-} 1%. The induction cells use core material for only a single pulse. A simple reverse bias circuit is used to reset the cores between pulses, and the insulator has been redesigned to withstand the reverse reset voltage. This approach can be installed in stages so that the facility can be used for dual axis radiography while implementing the multi-pulsing capability. A dual double-pulse format has been identified which provides a sequence of two pulses along one line-of-sight within a 2-{micro}sec window. The 2-{micro}sec windows can be separated by arbitrary time intervals of 2- to 10-{micro}sec.

  15. Film holder for radiographing tubing

    DOE Patents [OSTI]

    Davis, Earl V.; Foster, Billy E.

    1976-01-01

    A film cassette is provided which may be easily placed about tubing or piping and readily held in place while radiographic inspection is performed. A pair of precurved light-impervious semi-rigid plastic sheets, hinged at one edge, enclose sheet film together with any metallic foils or screens. Other edges are made light-tight with removable caps, and the entire unit is held securely about the object to be radiographed with a releasable fastener such as a strip of Velcro.

  16. Vertical Axis Wind Turbine

    Energy Science and Technology Software Center (OSTI)

    2002-04-01

    Blade fatigue life is an important element in determining the economic viability of the Vertical-Axis Wind Turbine (VAWT). VAWT-SAL Vertical Axis Wind Turbine- Stochastic Aerodynamic Loads Ver 3.2 numerically simulates the stochastic (random0 aerodynamic loads of the Vertical-Axis Wind Turbine (VAWT) created by the atomspheric turbulence. The program takes into account the rotor geometry, operating conditions, and assumed turbulence properties.

  17. Radiographic Inspection of Fueled Clads

    SciTech Connect (OSTI)

    Timothy J. Roney; Karen M. Wendt

    2005-04-01

    Five general purpose heat source (GPHS) fueled clads were radiographically inspected at the Idaho National Laboratory (INL). The girth weld region of each clad had previously passed visual examination, ring gauge test, and leak test but showed “positive” indications on the ultrasonic (UT) test. Positive ultrasonic indications are allowable under certain weld conditions; radiographic inspection provides a secondary nonintrusive means of clad inspection and may confirm allowable anomalies from the UT inspection. All the positive UT indications were found to exhibit allowable weld shield fusion or mismatch conditions. No indication of void defects was found. One additional clad (FCO371) was deemed unacceptable for radiographic inspection due to an unknown black substance that obscured the angular origin on the weld so that the angular offset to the UT indication could not be found.

  18. Los Alamos National Laboratory to begin DARHT 2 operations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    DARHT 2 operations begin Los Alamos National Laboratory to begin DARHT 2 operations The Dual Axis Radiographic Hydrodynamic Test facility has officially become "dual" with...

  19. Dual Career Services

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Options Dual Career Services Dual Career Services Los Alamos Lab recruits the best minds on the planet and offers job search information and assistance to our dual career...

  20. National Wind Tecnology Center Provides Dual Axis Resonant Blade Testing

    ScienceCinema (OSTI)

    Felker, Fort

    2014-06-10

    NREL's Structural Testing Laboratory at the National Wind Technology Center (NWTC) provides experimental laboratories, computer facilities for analytical work, space for assembling components and turbines for atmospheric testing as well as office space for industry researchers. Fort Felker, center director at the NWTC, discusses NREL's state-of-the-art structural testing capabilities and shows a flapwise and edgewise blade test in progress.

  1. National Wind Tecnology Center Provides Dual Axis Resonant Blade Testing

    SciTech Connect (OSTI)

    Felker, Fort

    2013-11-13

    NREL's Structural Testing Laboratory at the National Wind Technology Center (NWTC) provides experimental laboratories, computer facilities for analytical work, space for assembling components and turbines for atmospheric testing as well as office space for industry researchers. Fort Felker, center director at the NWTC, discusses NREL's state-of-the-art structural testing capabilities and shows a flapwise and edgewise blade test in progress.

  2. advanced radiographic capability | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    advanced radiographic capability ARC will make tiny "movies" of thermonuclear and stockpile experiments The National Ignition Facility's (NIF) performed the first programmatic experiments with Advanced Radiographic Capability (ARC) on December 1-3, 2015. ARC, a petawatt-class laser with peak power that will exceed a quadrillion watts, is designed to produce brighter, more penetrating, higher-energy

  3. Microsoft Word - newletter August 2007 v5.doc

    National Nuclear Security Administration (NNSA)

    3 Dual Axis Radiographic Hydrodynamics Test (DARHT) 2 nd Axis Achieves Full ... between the laboratories, the Nevada Test Site, and other DOENNSA organizations. ...

  4. Vertical axis wind turbines

    DOE Patents [OSTI]

    Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij

    2011-03-08

    A vertical axis wind turbine is described. The wind turbine can include a top ring, a middle ring and a lower ring, wherein a plurality of vertical airfoils are disposed between the rings. For example, three vertical airfoils can be attached between the upper ring and the middle ring. In addition, three more vertical airfoils can be attached between the lower ring and the middle ring. When wind contacts the vertically arranged airfoils the rings begin to spin. By connecting the rings to a center pole which spins an alternator, electricity can be generated from wind.

  5. Vertical axis wind turbine airfoil

    DOE Patents [OSTI]

    Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij Vasiljevich

    2012-12-18

    A vertical axis wind turbine airfoil is described. The wind turbine airfoil can include a leading edge, a trailing edge, an upper curved surface, a lower curved surface, and a centerline running between the upper surface and the lower surface and from the leading edge to the trailing edge. The airfoil can be configured so that the distance between the centerline and the upper surface is the same as the distance between the centerline and the lower surface at all points along the length of the airfoil. A plurality of such airfoils can be included in a vertical axis wind turbine. These airfoils can be vertically disposed and can rotate about a vertical axis.

  6. Two-axis angular effector

    DOE Patents [OSTI]

    Vaughn, Mark R.; Robinett, III, Rush D.; Phelan, John R.; Van Zuiden, Don M.

    1997-01-21

    A new class of coplanar two-axis angular effectors. These effectors combine a two-axis rotational joint analogous to a Cardan joint with linear actuators in a manner to produce a wider range of rotational motion about both axes defined by the joint. This new class of effectors also allows design of robotic manipulators having very high strength and efficiency. These effectors are particularly suited for remote operation in unknown surroundings, because of their extraordinary versatility. An immediate application is to the problems which arise in nuclear waste remediation.

  7. Iterative Reconstruction of Coded Source Neutron Radiographs

    SciTech Connect (OSTI)

    Santos-Villalobos, Hector J; Bingham, Philip R; Gregor, Jens

    2012-01-01

    Use of a coded source facilitates high-resolution neutron imaging but requires that the radiographic data be deconvolved. In this paper, we compare direct deconvolution with two different iterative algorithms, namely, one based on direct deconvolution embedded in an MLE-like framework and one based on a geometric model of the neutron beam and a least squares formulation of the inverse imaging problem.

  8. A Radiographic Technique With Heavy Ion Microbeams

    SciTech Connect (OSTI)

    Muscio, J.; Somacal, H.; Burlon, A. A.; Debray, M. E.; Valda, A. A.; Kreiner, A. J.; Kesque, J. M.; Minsky, D. M.

    2007-02-12

    In this work, we introduce a new technique to perform densitometric and multielemental analysis of samples at the same time using a simple detector with heavy ion micro-beams. It consists in the simultaneous analysis of X-rays induced in the sample and in a secondary target arranged behind the specimen. The X-rays originated in the secondary target are attenuated when crossing the specimen producing a radiographic image with a monochromatic source.

  9. Three axis velocity probe system

    DOE Patents [OSTI]

    Fasching, George E.; Smith, Jr., Nelson S.; Utt, Carroll E.

    1992-01-01

    A three-axis velocity probe system for determining three-axis positional velocities of small particles in fluidized bed systems and similar applications. This system has a sensor head containing four closely-spaced sensing electrodes of small wires that have flat ends to establish a two axis plane, e.g. a X-Y plane. Two of the sensing electrodes are positioned along one of the axes and the other two are along the second axis. These four sensing electrodes are surrounded by a guard electrode, and the outer surface is a ground electrode and support member for the sensing head. The electrodes are excited by, for example, sinusoidal voltage having a peak-to-peak voltage of up to 500 volts at a frequency of 2 MHz. Capacitive currents flowing between the four sensing electrodes and the ground electrode are influenced by the presence and position of a particle passing the sensing head. Any changes in these currents due to the particle are amplified and synchronously detected to produce positional signal values that are converted to digital form. Using these digital forms and two values of time permit generation of values of the three components of the particle vector and thus the total velocity vector.

  10. Metrics for Developing an Endorsed Set of Radiographic Threat Surrogates for JINII/CAARS

    SciTech Connect (OSTI)

    Wurtz, R; Walston, S; Dietrich, D; Martz, H

    2009-02-11

    CAARS (Cargo Advanced Automated Radiography System) is developing x-ray dual energy and x-ray backscatter methods to automatically detect materials that are greater than Z=72 (hafnium). This works well for simple geometry materials, where most of the radiographic path is through one material. However, this is usually not the case. Instead, the radiographic path includes many materials of different lengths. Single energy can be used to compute {mu}y{sub l} which is related to areal density (mass per unit area) while dual energy yields more information. This report describes a set of metrics suitable and sufficient for characterizing the appearance of assemblies as detected by x-ray radiographic imaging systems, such as those being tested by Joint Integrated Non-Intrusive Inspection (JINII) or developed under CAARS. These metrics will be simulated both for threat assemblies and surrogate threat assemblies (such as are found in Roney et al. 2007) using geometrical and compositional information of the assemblies. The imaging systems are intended to distinguish assemblies containing high-Z material from those containing low-Z material, regardless of thickness, density, or compounds and mixtures. The systems in question operate on the principle of comparing images obtained by using two different x-ray end-point energies--so-called 'dual energy' imaging systems. At the direction of the DHS JINII sponsor, this report does not cover metrics that implement scattering, in the form of either forward-scattered radiation or high-Z detection systems operating on the principle of backscatter detection. Such methods and effects will be covered in a later report. The metrics described here are to be used to compare assemblies and not x-ray radiography systems. We intend to use these metrics to determine whether two assemblies do or do not look the same. We are tasked to develop a set of assemblies whose appearance using this class of detection systems is indistinguishable from the

  11. NNSA releases Stockpile Stewardship Program quarterly experiments...

    National Nuclear Security Administration (NNSA)

    the Dual Axis Radiographic Hydrodynamic Test facility at Los Alamos National ... All of the NNSA research, development, test, and evaluation experimental facilities are ...

  12. NNSA's Summary of Experiments Conducted in Support of Stockpile...

    National Nuclear Security Administration (NNSA)

    These include some of the most sophisticated scientific research facilities in the world including, the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos ...

  13. NNSA's Stockpile Stewardship Program Quarterly Experiments summary...

    National Nuclear Security Administration (NNSA)

    These include some of the most sophisticated scientific research facilities in the world including, the Dual Axis Radiographic Hydrodynamic Test facility at Los Alamos National ...

  14. Proton Radiography at LANL | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    is the Dual-Axis Radiographic Hydrodynamic Test facility, or DARHT. Recently completed at ... of proton radiography's ability to measure small density differences inside a test object. ...

  15. Research and Development | National Nuclear Security Administration...

    National Nuclear Security Administration (NNSA)

    Research, Development, Test, and Evaluation Research and Development Photo: DARHT's ... as the Dual Axis Radiographic Hydrodynamic Test Facility (DARHT), Site 300, Z, Nevada ...

  16. SSQ V1 N1_24feb11_FINAL

    National Nuclear Security Administration (NNSA)

    The Dual Axis Radiographic Hydrodynamic Test facility really demonstrated what an ... experiment is to test the predictions for the initial conditions of primary implosion. ...

  17. EIS-0228: Record of Decision | Department of Energy

    Office of Environmental Management (EM)

    Hydrodynamic Test Facility The Department of Energy (DOE) is issuing this Record of Decision (ROD) regarding the DOE's proposed Dual Axis Radiographic Hydrodynamic Test (DARHT) ...

  18. NNSA, LANL Complete DARHT Improvements With Successful Multi...

    National Nuclear Security Administration (NNSA)

    NNSA, LANL Complete DARHT Improvements With Successful Multi-frame Hydrodynamic Test ... (LANL) Dual Axis Radiographic Hydrodynamic Test (DARHT) facility has completed another ...

  19. Flexible helical-axis stellarator

    DOE Patents [OSTI]

    Harris, Jeffrey H.; Hender, Timothy C.; Carreras, Benjamin A.; Cantrell, Jack L.; Morris, Robert N.

    1988-01-01

    An 1=1 helical winding which spirals about a conventional planar, circular central conductor of a helical-axis stellarator adds a significant degree of flexibility by making it possible to control the rotational transform profile and shear of the magnetic fields confining the plasma in a helical-axis stellarator. The toroidal central conductor links a plurality of toroidal field coils which are separately disposed to follow a helical path around the central conductor in phase with the helical path of the 1=1 winding. This coil configuration produces bean-shaped magnetic flux surfaces which rotate around the central circular conductor in the same manner as the toroidal field generating coils. The additional 1=1 winding provides flexible control of the magnetic field generated by the central conductor to prevent the formation of low-order resonances in the rotational transform profile which can produce break-up of the equilibrium magnetic surfaces. Further, this additional winding can deepen the magnetic well which together with the flexible control provides increased stability.

  20. Helical axis stellarator with noninterlocking planar coils

    DOE Patents [OSTI]

    Reiman, Allan; Boozer, Allen H.

    1987-01-01

    A helical axis stellarator using only noninterlocking planar, non-circular coils, generates magnetic fields having a magnetic well and large rotational transform with resultant large equilibrium beta.

  1. A proposed benchmark for simulation in radiographic testing

    SciTech Connect (OSTI)

    Jaenisch, G.-R.; Deresch, A.; Bellon, C.; Schumm, A.; Guerin, P.

    2014-02-18

    The purpose of this benchmark study is to compare simulation results predicted by various models of radiographic testing, in particular those that are capable of separately predicting primary and scatter radiation for specimens of arbitrary geometry.

  2. Radiograph and passive data analysis using mixed variable optimization...

    Office of Scientific and Technical Information (OSTI)

    In this embodiment, the computer is configured to input the radiographic image data from the two-dimensional detector and to determine one or more materials that form the object by ...

  3. Actuator assembly including a single axis of rotation locking member

    DOE Patents [OSTI]

    Quitmeyer, James N.; Benson, Dwayne M.; Geck, Kellan P.

    2009-12-08

    An actuator assembly including an actuator housing assembly and a single axis of rotation locking member fixedly attached to a portion of the actuator housing assembly and an external mounting structure. The single axis of rotation locking member restricting rotational movement of the actuator housing assembly about at least one axis. The single axis of rotation locking member is coupled at a first end to the actuator housing assembly about a Y axis and at a 90.degree. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The single axis of rotation locking member is coupled at a second end to a mounting structure, and more particularly a mounting pin, about an X axis and at a 90.degree. angle to a Y and Z axis providing rotation of the actuator housing assembly about the X axis. The actuator assembly is thereby restricted from rotation about the Z axis.

  4. Innovative Offshore Vertical-Axis Wind Turbine Rotors

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Offshore Vertical-Axis Wind Turbine Rotors - Sandia Energy Energy Search Icon Sandia Home ... Google + Vimeo Newsletter Signup SlideShare Innovative Offshore Vertical-Axis Wind Turbine ...

  5. Modular off-axis solar concentrator

    DOE Patents [OSTI]

    Plesniak, Adam P; Hall, John C

    2015-01-27

    A solar concentrator including a housing defining a vertical axis and including a receiving wall connected to a reflecting wall to define an internal volume and an opening into the internal volume, wherein the reflecting wall defines at least one primary optical element, and wherein at least a portion of the reflecting wall includes a layer of reflective material, the housing further including a cover connected to the receiving wall and the reflecting wall to seal the opening, and at least one receiver mounted on the receiving wall such that a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, the receiver including at least one photovoltaic cell.

  6. Enclosed, off-axis solar concentrator

    DOE Patents [OSTI]

    Benitez, Pablo; Grip, Robert E; Minano, Juan C; Narayanan, Authi A; Plesniak, Adam; Schwartz, Joel A

    2013-11-26

    A solar concentrator including a housing having receiving wall, a reflecting wall and at least two end walls, the receiving, reflecting and end walls defining a three-dimensional volume having an inlet, wherein a vertical axis of the housing is generally perpendicular to the inlet, a receiver mounted on the receiving wall of the housing, the receiver including at least one photovoltaic cell, wherein a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, at least one clip disposed on the reflecting wall an optical element received within the three-dimensional volume, the optical element including at least one tab, the tab being engaged by the clip to align the optical element with the receiver, and a window received over the inlet to enclose the housing.

  7. Aeroelastically coupled blades for vertical axis wind turbines

    DOE Patents [OSTI]

    Paquette, Joshua; Barone, Matthew F.

    2016-02-23

    Various technologies described herein pertain to a vertical axis wind turbine blade configured to rotate about a rotation axis. The vertical axis wind turbine blade includes at least an attachment segment, a rear swept segment, and optionally, a forward swept segment. The attachment segment is contiguous with the forward swept segment, and the forward swept segment is contiguous with the rear swept segment. The attachment segment includes a first portion of a centroid axis, the forward swept segment includes a second portion of the centroid axis, and the rear swept segment includes a third portion of the centroid axis. The second portion of the centroid axis is angularly displaced ahead of the first portion of the centroid axis and the third portion of the centroid axis is angularly displaced behind the first portion of the centroid axis in the direction of rotation about the rotation axis.

  8. PHERMEX: pulsed high energy radiographic machine emitting x-rays

    SciTech Connect (OSTI)

    Dick, R.D.

    1983-01-01

    The PHERMEX facility used to provide flash radiographs of explosives and explosive-driven metal systems is described. With this facility, precision radiographs of large objects containing materials with high atomic number and high density are attainable. PHERMEX encompass the high-current, three-cavity, 30-MeV linear electron accelerator; the 50-MHz radio-frequency power source to drive the cavities; timing, and signal detection system; and a data-acquisition system. Some unique features of PHERMEX are reliability; very intense sub-microsecond bremsstrahlung source rich in 4- to 8-MeV x rays; less than 1.0-mm-diam spot size; precision determination of edges, discontinuities, and areal-mass distribution; and flash radiographs of large explosive systems close to the x-ray target. Some aspects of the PHERMEX-upgrading program are discussed. The program will result in (1) an increased electron-beam energy to about 50 MeV, (2) the use of an electron-gun pulser that is capable of producing three-time-adjustable pulses for obtaining three radiographic pictures of a single explosive event, (3) an increased electron injection energy of 1.25 MeV, (4) the capability for recording high-speed signals, and (5) the use of computers to assist the monitoring and control of the data-acquisition system and the PHERMEX accelerator.

  9. PHERMEX: Pulsed High-Energy Radiographic Machine Emitting X rays

    SciTech Connect (OSTI)

    Dick, R.D.

    1981-01-01

    The PHERMEX facility used to provide flash radiographs of explosives and explosive-driven metal systems is described. With this facility, precision radiographs of large objects containing materials with high atomic number and high density are attainable. PHERMEX encompasses the high-current, three-cavity, 30-MeV linear electron accelerator; the 50-MHz-radiofrequency power source to drive the cavities; timing, firing, and signal detection system; and a data-acquisition system. Some unique features of PHERMEX are reliability; very intensive submicrosecond bremsstrahlung source rich in 4- to 8-MeV x rays; less than 1.0-mm-diam spot size; precision determination of edges, discontinuities, and areal-mass distribution; and flash radiographs of large explosive systems close to the x-ray target. Some aspects of the PHERMEX-upgrading program are discussed. The program will result (1) in an increased electron-beam energy to about 50 MeV, (2) the use of an electron-gun pulser that is capable of producing three time-adjustable pulses for obtaining three radiographic pictures of a single explosive event, (3) an increased electron injection energy of 1.25 MeV, (4) the capability for recording high-speed signals, and (5) the use of computers to assist the monitoring and control of the data-acquisition system and the PHERMEX accelerator.

  10. New finding in the radiographic diagnosis of Achilles tendon rupture

    SciTech Connect (OSTI)

    Newmark, H.; Mellon, W.S. Jr.; Malhotra, A.K.; Olken, S.M.; Halls, J.

    1982-06-01

    The authors describe a new radiographic sign of rupture of the Achilles tendon system. It is a fracture, with separation through an osteophyte at the insertion of this tendon. Previously reported signs are also discussed as well as the present case report.

  11. RELIABLE RADIOGRAPHIC INSPECTION OF FLEXIBLE RISERS FOR THE OIL INDUSTRY

    SciTech Connect (OSTI)

    Almeida, Romulo M.; Rebello, Joao Marcos A. [Department of Metallurgical and Materials Engineering COPPE/UFRJ-Federal University of Rio de Janeiro P.O. Box 68505 CEP 21941-972, Rio de Janeiro RJ (Brazil); Vaz, Murilo A. [Department of Ocean Engineering-COPPE/UFRJ (Brazil)

    2010-02-22

    Flexible risers are composite tubular structures manufactured by the concentric assemblage of cylindrical polymeric and helically wound metallic layers employed to convey pressurized fluids such as oil, gas and water in the ocean environment. The metallic layers account for the flexible risers' structural strength and are dimensioned according to the static and dynamic loads. They are usually installed in a free hanging catenary configuration and are subjected to the direct action of waves and marine currents and wave induced motions from the oil production platform. The fatigue rupture of wire armours in the end fitting or within the riser segment protected by the bend stiffener is an object of major concern. Integrity models have been developed, however inspection techniques are mandatory to ensure that failure is detected. Gammagraphy has been used as a common inspection technique in all regions of the flexible riser, mainly with the single wall-single view method. On the other side, there is not any qualified radiographic procedure to this kind of structure. Radiographic simulation was adopted and its validation with actual gammagraphies and establishment of radiographic parameters to complex radiation geometries were done. Results show the viability of the radiographic inspection analyzing the armour wires' rupture and the displacement between wires.

  12. CHARACTERIZATION OF THE ADVANCED RADIOGRAPHIC CAPABILITY FRONT END ON NIF

    SciTech Connect (OSTI)

    Haefner, C; Heebner, J; Dawson, J; Fochs, S; Shverdin, M; Crane, J K; Kanz, V K; Halpin, J; Phan, H; Sigurdsson, R; Brewer, W; Britten, J; Brunton, G; Clark, W; Messerly, M J; Nissen, J D; Nguyen, H; Shaw, B; Hackel, R; Hermann, M; Tietbohl, G; Siders, C W; Barty, C J

    2009-07-15

    We have characterized the Advanced Radiographic Capability injection laser system and demonstrated that it meets performance requirements for upcoming National Ignition Facility fusion experiments. Pulse compression was achieved with a scaled down replica of the meter-scale grating ARC compressor and sub-ps pulse duration was demonstrated at the Joule-level.

  13. Two-axis tracking solar collector mechanism

    SciTech Connect (OSTI)

    Johnson, K.C.

    1990-11-06

    This patent describes a tracking solar collector mechanism. It comprises: a stationary base structure which supports the tracking components; two parallel rows of uniformly spaced axial polar bearings attached to the base structure, each row comprising at least one bearing, wherein each member bearing of each row is coaligned with an associated bearing of the other row, the line joining each pair of coaligned polar bearings defining an associated polar tracking axis wherein the pair's polar axes are mutually parallel and are adapted to be aligned with the Earth's axis; at least one tracking module, each of which is supported by and turns on one of the pairs of coaligned polar bearings.

  14. Radiograph and passive data analysis using mixed variable optimization

    DOE Patents [OSTI]

    Temple, Brian A.; Armstrong, Jerawan C.; Buescher, Kevin L.; Favorite, Jeffrey A.

    2015-06-02

    Disclosed herein are representative embodiments of methods, apparatus, and systems for performing radiography analysis. For example, certain embodiments perform radiographic analysis using mixed variable computation techniques. One exemplary system comprises a radiation source, a two-dimensional detector for detecting radiation transmitted through a object between the radiation source and detector, and a computer. In this embodiment, the computer is configured to input the radiographic image data from the two-dimensional detector and to determine one or more materials that form the object by using an iterative analysis technique that selects the one or more materials from hierarchically arranged solution spaces of discrete material possibilities and selects the layer interfaces from the optimization of the continuous interface data.

  15. A Bayesian Measurment Error Model for Misaligned Radiographic Data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lennox, Kristin P.; Glascoe, Lee G.

    2013-09-06

    An understanding of the inherent variability in micro-computed tomography (micro-CT) data is essential to tasks such as statistical process control and the validation of radiographic simulation tools. The data present unique challenges to variability analysis due to the relatively low resolution of radiographs, and also due to minor variations from run to run which can result in misalignment or magnification changes between repeated measurements of a sample. Positioning changes artificially inflate the variability of the data in ways that mask true physical phenomena. We present a novel Bayesian nonparametric regression model that incorporates both additive and multiplicative measurement error inmore » addition to heteroscedasticity to address this problem. We also use this model to assess the effects of sample thickness and sample position on measurement variability for an aluminum specimen. Supplementary materials for this article are available online.« less

  16. A Bayesian Measurment Error Model for Misaligned Radiographic Data

    SciTech Connect (OSTI)

    Lennox, Kristin P.; Glascoe, Lee G.

    2013-09-06

    An understanding of the inherent variability in micro-computed tomography (micro-CT) data is essential to tasks such as statistical process control and the validation of radiographic simulation tools. The data present unique challenges to variability analysis due to the relatively low resolution of radiographs, and also due to minor variations from run to run which can result in misalignment or magnification changes between repeated measurements of a sample. Positioning changes artificially inflate the variability of the data in ways that mask true physical phenomena. We present a novel Bayesian nonparametric regression model that incorporates both additive and multiplicative measurement error in addition to heteroscedasticity to address this problem. We also use this model to assess the effects of sample thickness and sample position on measurement variability for an aluminum specimen. Supplementary materials for this article are available online.

  17. High payload six-axis load sensor

    DOE Patents [OSTI]

    Jansen, John F.; Lind, Randall F.

    2003-01-01

    A repairable high-payload six-axis load sensor includes a table, a base, and at least three shear-pin load transducers removably mounted between the table and the base. Removable mounting permits easy replacement of damaged shear pins. Preferably, the shear-pin load transducers are responsive to shear forces imparted along the two axes perpendicular to an axis of minimum sensitivity characteristic of the transducer. Responsive to an applied shear force, each shear-pin load transducer can produce an electrical signal proportional to the reaction force. The load sensor can further include a structure for receiving the proportional electrical signals and computing the applied load corresponding to the proportional electrical signals. The computed load can be expressed in terms of a three-dimensional XYZ Cartesian coordinate system.

  18. Application of Perona Malik anisotropic diffusion on digital radiographic image

    SciTech Connect (OSTI)

    Halim, Suhaila Abd; Razak, Rohayu Abdul; Ibrahim, Arsmah; Manurung, Yupiter HP

    2014-07-10

    Perona Malik Anisotropic Diffusion (PMAD) is a very useful and efficient denoising technique if the parameters are properly selected. Overestimating the parameters may cause oversmoothed and underestimating it may leave unfiltered noise. This makes the selection of parameters a crucial process. In this paper the PMAD model is solved using a finite difference scheme The discretized model is evaluated using different diffusion coefficient of exponential and quadratic on defective radiographic images in terms of quality and efficiency. In the application of the PMAD model on image data, a set of defective radiographic images of welding is used as input data. Peak Signal to Noise Ratio (PSNR), Structural Similarity Measure (SSIM) and temporal time are used to evaluate the performance of the model. The implementation of the experiment has been carried out using MATLAB R2009a. In terms of quality, results show that the Quadratic Diffusion Coefficient Function (QDCF) provides better results compared with the Exponential Diffusion Coefficient Function (EDCF). In conclusion, the denoising effect using PMAD model based on finite difference scheme shows able to improve image quality by removing noise in the defective radiographic image.

  19. Offshore Ambitions for the Vertical-Axis Wind Turbine

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ambitions for the Vertical-Axis Wind Turbine - Sandia Energy Energy Search Icon Sandia ... Offshore Ambitions for the Vertical-Axis Wind Turbine HomeEnergy, News, News & Events, ...

  20. Three-axis asymmetric radiation detector system

    DOE Patents [OSTI]

    Martini, Mario Pierangelo (Oak Ridge, TN); Gedcke, Dale A. (Oak Ridge, TN); Raudorf, Thomas W. (Oak Ridge, TN); Sangsingkeow, Pat (Knoxville, TN)

    2000-01-01

    A three-axis radiation detection system whose inner and outer electrodes are shaped and positioned so that the shortest path between any point on the inner electrode and the outer electrode is a different length whereby the rise time of a pulse derived from a detected radiation event can uniquely define the azimuthal and radial position of that event, and the outer electrode is divided into a plurality of segments in the longitudinal axial direction for locating the axial location of a radiation detection event occurring in the diode.

  1. Dual Tank Fuel System

    SciTech Connect (OSTI)

    Wagner, Richard William; Burkhard, James Frank; Dauer, Kenneth John

    1999-11-16

    A dual tank fuel system has primary and secondary fuel tanks, with the primary tank including a filler pipe to receive fuel and a discharge line to deliver fuel to an engine, and with a balance pipe interconnecting the primary tank and the secondary tank. The balance pipe opens close to the bottom of each tank to direct fuel from the primary tank to the secondary tank as the primary tank is filled, and to direct fuel from the secondary tank to the primary tank as fuel is discharged from the primary tank through the discharge line. A vent line has branches connected to each tank to direct fuel vapor from the tanks as the tanks are filled, and to admit air to the tanks as fuel is delivered to the engine.

  2. Dual surface interferometer

    DOE Patents [OSTI]

    Pardue, Robert M.; Williams, Richard R.

    1982-01-01

    A double-pass interferometer is provided which allows direct measurement of relative displacement between opposed surfaces. A conventional plane mirror interferometer may be modified by replacing the beam-measuring path cube-corner reflector with an additional quarter-wave plate. The beam path is altered to extend to an opposed plane mirrored surface and the reflected beam is placed in interference with a retained reference beam split from dual-beam source and retroreflected by a reference cube-corner reflector mounted stationary with the interferometer housing. This permits direct measurement of opposed mirror surfaces by laser interferometry while doubling the resolution as with a conventional double-pass plane mirror laser interferometer system.

  3. Dual surface interferometer

    DOE Patents [OSTI]

    Pardue, R.M.; Williams, R.R.

    1980-09-12

    A double-pass interferometer is provided which allows direct measurement of relative displacement between opposed surfaces. A conventional plane mirror interferometer may be modified by replacing the beam-measuring path cube-corner reflector with an additional quarterwave plate. The beam path is altered to extend to an opposed plane mirrored surface and the reflected beam is placed in interference with a retained reference beam split from dual-beam source and retroreflected by a reference cube-corner reflector mounted stationary with the interferometer housing. This permits direct measurement of opposed mirror surfaces by laser interferometry while doubling the resolution as with a conventional double-pass plane mirror laser interferometer system.

  4. Outpatient radiographic exposure in the first five years of life

    SciTech Connect (OSTI)

    Fosarelli, P.D.; DeAngelis, C.

    1987-06-01

    Young children receive a variety of diagnostic radiographs over time. In some cases the exposure to radiation may be unwarranted because the films may yield confusing results, or may also need to be repeated because of poor technical quality. Even when the results are clearly negative, the subsequent treatment may proceed as if the film had been positive because of the child's clinical condition. The cumulative effect of such low-dose radiation on infants and children over time is unknown. The number and types of outpatient radiographs received by a cohort of poor children from a hospital-based continuity clinic during their first 5 years of life were reviewed. Also noted were the reason for obtaining the film, whether it was positive for that reason or another, whether the child had a chronic condition that prompted the use of radiograph, and the child's sex, race, and age when the film was obtained. Of the 218 children, 132 (60.6%) received 349 sets of films in their first 5 years. There was no difference in the number of films by race or sex. Chest and posttrauma bone or joint films accounted for 315 sets of films or 90.3% of the total. Overall, 25.8% of the 267 chest films were positive; this varied by age. Only 15% of the chest films were positive in the first year compared with 29 to 49% in the second through fifth years (p less than 0.001). Cough was the respiratory symptom most reliably associated with a positive chest film, both for the cohort (p less than 0.0001) and for children in the first year of life (p less than 0.01).

  5. Patient-based radiographic exposure factor selection: a systematic review

    SciTech Connect (OSTI)

    Ching, William; Robinson, John; McEntee, Mark

    2014-09-15

    Digital technology has wider exposure latitude and post-processing algorithms which can mask the evidence of underexposure and overexposure. Underexposure produces noisy, grainy images which can impede diagnosis and overexposure results in a greater radiation dose to the patient. These exposure errors can result from inaccurate adjustment of exposure factors in response to changes in patient thickness. This study aims to identify all published radiographic exposure adaptation systems which have been, or are being, used in general radiography and discuss their applicability to digital systems. Studies in EMBASE, MEDLINE, CINAHL and SCOPUS were systematically reviewed. Some of the search terms used were exposure adaptation, exposure selection, exposure technique, 25% rule, 15% rule, DuPont™ Bit System and radiography. A manual journal-specific search was also conducted in The Radiographer and Radiologic Technology. Studies were included if they demonstrated a system of altering exposure factors to compensate for variations in patients for general radiography. Studies were excluded if they focused on finding optimal exposures for an ‘average’ patient or focused on the relationship between exposure factors and dose. The database search uncovered 11 articles and the journal-specific search uncovered 13 articles discussing systems of exposure adaptation. They can be categorised as simple one-step guidelines, comprehensive charts and computer programs. Only two papers assessed the efficacy of exposure adjustment systems. No literature compares the efficacy of exposure adaptations system for film/screen radiography with digital radiography technology nor is there literature on a digital specific exposure adaptation system.

  6. Vertical-Axis Wind Turbine Mesh Generator

    SciTech Connect (OSTI)

    2014-01-24

    VAWTGen is a mesh generator for creating a finite element beam mesh of arbitrary vertical-axis wind turbines (VAWT). The software accepts input files specifying tower and blade structural and aerodynamic descriptions and constructs a VAWT using a minimal set of inputs. VAWTs with an arbitrary number of blades can be constructed with or without a central tower. Strut connections between the tower and blades can be specified in an arbitrary manner. The software also facilitates specifying arbitrary joints between structural components and concentrated structural tenns (mass and stiffness). The output files which describe the VAWT configuration are intended to be used with the Offshore Wind ENergy Simulation (OWENS) Toolkit software for structural dynamics analysis of VAWTs. Furthermore, VAWTGen is useful for visualizing output from the OWENS analysis software.

  7. Vertical-Axis Wind Turbine Mesh Generator

    Energy Science and Technology Software Center (OSTI)

    2014-01-24

    VAWTGen is a mesh generator for creating a finite element beam mesh of arbitrary vertical-axis wind turbines (VAWT). The software accepts input files specifying tower and blade structural and aerodynamic descriptions and constructs a VAWT using a minimal set of inputs. VAWTs with an arbitrary number of blades can be constructed with or without a central tower. Strut connections between the tower and blades can be specified in an arbitrary manner. The software also facilitatesmore » specifying arbitrary joints between structural components and concentrated structural tenns (mass and stiffness). The output files which describe the VAWT configuration are intended to be used with the Offshore Wind ENergy Simulation (OWENS) Toolkit software for structural dynamics analysis of VAWTs. Furthermore, VAWTGen is useful for visualizing output from the OWENS analysis software.« less

  8. Two-axis tracking solar collector mechanism

    DOE Patents [OSTI]

    Johnson, K.C.

    1992-12-08

    This invention is a novel solar tracking mechanism incorporating a number of practical features that give it superior environmental resilience and exceptional tracking accuracy. The mechanism comprises a lightweight space-frame assembly supporting an array of point-focus Fresnel lenses in a two-axis tracking structure. The system is enclosed under a glass cover which isolates it from environmental exposure and enhances tracking accuracy by eliminating wind loading. Tracking accuracy is also enhanced by the system's broad-based tracking support. The system's primary intended application would be to focus highly concentrated sunlight into optical fibers for transmission to core building illumination zones, and the system may also have potential for photovoltaic or photothermal solar energy conversion. 16 figs.

  9. Two-axis tracking solar collector mechanism

    DOE Patents [OSTI]

    Johnson, Kenneth C.

    1992-01-01

    This invention is a novel solar tracking mechanism incorporating a number of practical features that give it superior environmental resilience and exceptional tracking accuracy. The mechanism comprises a lightweight space-frame assembly supporting an array of point-focus Fresnel lenses in a two-axis tracking structure. The system is enclosed under a glass cover which isolates it from environmental exposure and enhances tracking accuracy by eliminating wind loading. Tracking accuracy is also enhanced by the system's broad-based tracking support. The system's primary intended application would be to focus highly concentrated sunlight into optical fibers for transmission to core building illumination zones, and the system may also have potential for photovoltaic or photothermal solar energy conversion.

  10. Two-axis tracking solar collector mechanism

    DOE Patents [OSTI]

    Johnson, Kenneth C.

    1990-01-01

    This invention is a novel solar tracking mechanism incorporating a number of practical features that give it superior environmental resilience and exceptional tracking accuracy. The mechanism comprises a lightweight space-frame assembly supporting an array of point-focus Fresnel lenses in a two-axis tracking structure. The system is enclosed under a glass cover which isolates it from environmental exposure and enhances tracking accuracy by eliminating wind loading. Tracking accuracy is also enhanced by the system's broad-based tracking support. The system's primary intended application would be to focus highly concentrated sunlight into optical fibers for transmission to core building illumination zones, and the system may also have potential for photovoltaic or photothermal solar energy conversion.

  11. Dual flapper valve assembly

    SciTech Connect (OSTI)

    Clary, S.R.; Giusti, F. Jr.; Sproul, R.M.

    1989-07-11

    This patent describes a dual flapper valve assembly for limiting the loss of completion fluid in connection with a well service operation. The valve assembly consists of: tubular support means defining a flow passage; a first flapper valve assembly connected in series flow relation with the support means, the first flapper valve assembly having a valve closure member movable between first and second positions for closing and opening the flow passage; a second flapper valve assembly connected in series flow relation in the support means, the second flapper valve assembly having a valve closure member movable between open and closed passage positions for closing and opening the flow passage; a prop sleeve mounted within the support means, the prop sleeve being movable from an extended position in which it props the closure member of one flapper valve in the open passage position to a retracted position in which the closure member is disengaged and released for movement to the closed passage position, the valve closure member of one of the flapper valve assemblies being engageable by a wash pipe extending through the flow passage to prop the valve closure member in the open passage position, and being movable to the closed passage position upon retraction of the wash pipe out of the flow passage.

  12. Bertram Brockhouse, the Triple-axis Spectrometer, and Neutron...

    Office of Scientific and Technical Information (OSTI)

    Bertram Brockhouse, the Triple-axis Spectrometer, and Neutron Spectroscopy Resources with Additional Information Bertram Brockhouse Courtesy of McMaster University Bertram...

  13. Solasta aka The Eagle Axis | Open Energy Information

    Open Energy Info (EERE)

    Zip: 2458 Sector: Efficiency, Solar Product: Start-up planning to produce high-efficiency solar cells using nanoscale elements. References: Solasta (aka The Eagle Axis)1 This...

  14. MHK Technologies/Horizontal Axis Logarithmic Spiral Turbine ...

    Open Energy Info (EERE)

    Horizontal Axis Logarithmic Spiral Turbine < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Technology Profile Primary Organization Golden...

  15. Off-Axis Parabola Inserter - Laboratory for Laser Energetics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Axis Parabola Inserter - Laboratory for Laser Energetics Laboratory for Laser Energetics Logo Search Home Around the Lab Past Issues Past Quick Shots About Office of the Director ...

  16. Three-axis particle impact probe

    DOE Patents [OSTI]

    Fasching, George E.; Smith, Jr., Nelson S.; Utt, Carroll E.

    1992-01-01

    Three-axis particle impact probes detect particle impact vectors along x-, y-, and z-axes by spherical probe head mounted on the outer end of a shaft that is flexibly mounted in silicone rubber at the top of a housing so as to enable motion imparted to the head upon impact to be transmitted to a grounded electrode secured to the shaft within the housing. Excitable electrodes are mounted in the housing in a fixed position, spaced apart from the ground electrode and forming, with the ground electrode, capacitor pairs. Movement of the ground electrode results in changes in capacitance, and these difference in capacitance are used for measurement or derivation of momentum vectors along each of the three axes. In one embodiment, the ground electrode is mounted at the base of the shaft and is secured to a silicone rubber layer at the top of the housing, providing for cantilevered movement. In another embodiment, the shaft is mounted at its mid point in a flexible bushing so that it undergoes pivotal movement around that point.

  17. Control system for a vertical axis windmill

    DOE Patents [OSTI]

    Brulle, Robert V.

    1983-10-18

    A vertical axis windmill having a rotating structure is provided with a series of articulated vertical blades whose positions are controlled to maintain a constant RPM for the rotating structure, when wind speed is sufficient. A microprocessor controller is used to process information on wind speed, wind direction and RPM of the rotating structure to develop an electrical signal for establishing blade position. The preferred embodiment of the invention, when connected to a utility grid, is designed to generate 40 kilowatts of power when exposed to a 20 mile per hour wind. The control system for the windmill includes electrical blade actuators that modulate the blades of the rotating structure. Blade modulation controls the blade angle of attack, which in turn controls the RPM of the rotor. In the preferred embodiment, the microprocessor controller provides the operation logic and control functions. A wind speed sensor provides inputs to start or stop the windmill, and a wind direction sensor is used to keep the blade flip region at 90.degree. and 270.degree. to the wind. The control system is designed to maintain constant rotor RPM when wind speed is between 10 and 40 miles per hour.

  18. Yaw dynamics of horizontal axis wind turbines

    SciTech Connect (OSTI)

    Hansen, A.C. )

    1992-05-01

    Designers of a horizontal axis wind turbine yaw mechanism are faced with a difficult decision. They know that if they elect to use a yaw- controlled rotor then the system will suffer increased initial cost and increased inherent maintenance and reliability problems. On the other hand, if they elect to allow the rotor to freely yaw they known they will have to account for unknown and random, though bounded, yaw rates. They will have a higher-risk design to trade-off against the potential for cost savings and reliability improvement. The risk of a yaw-free system could be minimized if methods were available for analyzing and understanding yaw behavior. The complexity of yaw behavior has, until recently, discouraged engineers from developing a complete yaw analysis method. The objectives of this work are to (1) provide a fundamental understanding of free-yaw mechanics and the design concepts most effective at eliminating yaw problems, and (2) provide tested design tools and guidelines for use by free-yaw wind systems manufacturers. The emphasis is on developing practical and sufficiently accurate design methods.

  19. National Security, Weapons Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Security, Weapons Science National Security, Weapons Science National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place on Earth pursues a broader array of world-class scientific endeavors. CoMuEx» Explosives Center» Dual-Axis Radiographic Hydrodynamic Test Facility (DARHT) The Dual-Axis Radiographic Hydrodynamic Test Facility at Los Alamos National Laboratory is part of the DOE's stockpile stewardship

  20. old.new.factsheets.indd

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    DARHT Dual-Axis Radiographic Hydrodynamic Test Facility At the Los Alamos National Laboratory (LANL), the Dual-Axis Radiographic Hydrodynamic Test Facility, or DARHT, supports a critical component of LANL's primary mission: to ensure the safety, security, and effectiveness of nuclear weapons in our na- tion's stockpile. Los Alamos scientists built DARHT, the world's most powerful x-ray machine, to analyze mockups of nuclear weapons. The DARHT Facility DARHT consists of two linear induction

  1. Dual porosity gas evolving electrode

    DOE Patents [OSTI]

    Townsend, C.W.

    1994-11-15

    A dual porosity electrode is described for use in thermoelectrochemical systems where simultaneous transport of gas and liquid into and/or out of the electrode is required. The electrode includes catalytic electrode particles having diameters ranging from about 25 to 100 angstroms. The catalytic electrode particles are anchored to a support network in clusters which have internal pores ranging in size from 25 to 100 angstroms. The pores between the clusters range in size from between about 1 to 20 microns. A method for making the dual porosity electrodes is also disclosed.

  2. Dual porosity gas evolving electrode

    DOE Patents [OSTI]

    Townsend, Carl W.

    1994-01-01

    A dual porosity electrode for use in thermoelectrochemical systems where simultaneous transport of gas and liquid into and/or out of the electrode is required. The electrode includes catalytic electrode particles having diameters ranging from about 25 to 100 angstroms. The catalytic electrode particles are anchored to a support network in clusters which have internal pores ranging in size from 25 to 100 angstroms. The pores between the clusters range in size from between about 1 to 20 microns. A method for making the dual porosity electrodes is also disclosed.

  3. UWB dual burst transmit driver

    DOE Patents [OSTI]

    Dallum, Gregory E.; Pratt, Garth C.; Haugen, Peter C.; Zumstein, James M.; Vigars, Mark L.; Romero, Carlos E.

    2012-04-17

    A dual burst transmitter for ultra-wideband (UWB) communication systems generates a pair of precisely spaced RF bursts from a single trigger event. An input trigger pulse produces two oscillator trigger pulses, an initial pulse and a delayed pulse, in a dual trigger generator. The two oscillator trigger pulses drive a gated RF burst (power output) oscillator. A bias driver circuit gates the RF output oscillator on and off and sets the RF burst packet width. The bias driver also level shifts the drive signal to the level that is required for the RF output device.

  4. Spin-stabilized magnetic levitation without vertical axis of rotation

    DOE Patents [OSTI]

    Romero, Louis; Christenson, Todd; Aaronson, Gene

    2009-06-09

    The symmetry properties of a magnetic levitation arrangement are exploited to produce spin-stabilized magnetic levitation without aligning the rotational axis of the rotor with the direction of the force of gravity. The rotation of the rotor stabilizes perturbations directed parallel to the rotational axis.

  5. Dual shell pressure balanced vessel

    DOE Patents [OSTI]

    Fassbender, Alexander G.

    1992-01-01

    A dual-wall pressure balanced vessel for processing high viscosity slurries at high temperatures and pressures having an outer pressure vessel and an inner vessel with an annular space between the vessels pressurized at a pressure slightly less than or equivalent to the pressure within the inner vessel.

  6. Dual function conducting polymer diodes

    DOE Patents [OSTI]

    Heeger, Alan J.; Yu, Gang

    1996-01-01

    Dual function diodes based on conjugated organic polymer active layers are disclosed. When positively biased the diodes function as light emitters. When negatively biased they are highly efficient photodiodes. Methods of preparation and use of these diodes in displays and input/output devices are also disclosed.

  7. Developing radiographer roles in the context of advanced and consultant practice

    SciTech Connect (OSTI)

    Field, Lisa J; Snaith, Beverly A

    2013-03-15

    Skill-mix initiatives have provided opportunities for radiographers to develop roles and achieve their potential, thus contributing to radiographer retention rates and increased job satisfaction. This reflective article explores two radiographic roles within an interprofessional context including the implications for confidence, competence, and future sustainability. These were reporting roles which extended into two modalities, one into bone densitometry and another into ultrasound. This article discusses how successful skill mix can benefit the individual, their department, and NHS organization and that role expansion can develop a more dynamic and resourceful workforce with transferability of skills and attributes.

  8. Neuroimaging in adult penetrating brain injury: a guide for radiographers

    SciTech Connect (OSTI)

    Temple, Nikki; Donald, Cortny; Skora, Amanda; Reed, Warren

    2015-06-15

    Penetrating brain injuries (PBI) are a medical emergency, often resulting in complex damage and high mortality rates. Neuroimaging is essential to evaluate the location and extent of injuries, and to manage them accordingly. Currently, a myriad of imaging modalities are included in the diagnostic workup for adult PBI, including skull radiography, computed tomography (CT), magnetic resonance imaging (MRI) and angiography, with each modality providing their own particular benefits. This literature review explores the current modalities available for investigating PBI and aims to assist in decision making for the appropriate use of diagnostic imaging when presented with an adult PBI. Based on the current literature, the authors have developed an imaging pathway for adult penetrating brain injury that functions as both a learning tool and reference guide for radiographers and other health professionals. Currently, CT is recommended as the imaging modality of choice for the initial assessment of PBI patients, while MRI is important in the sub-acute setting where it aids prognosis prediction and rehabilitation planning, Additional follow-up imaging, such as angiography, should be dependent upon clinical findings.

  9. Off-axis illumination direct-to-digital holography

    DOE Patents [OSTI]

    Thomas, Clarence E.; Price, Jeffery R.; Voelkl, Edgar; Hanson, Gregory R.

    2004-06-08

    Systems and methods are described for off-axis illumination direct-to-digital holography. A method of recording an off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis, includes: reflecting a reference beam from a reference mirror at a non-normal angle; reflecting an object beam from an object at an angle with respect to an optical axis defined by a focusing lens; focusing the reference beam and the object beam at a focal plane of a digital recorder to form the off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; digitally recording the off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; Fourier analyzing the recorded off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes by transforming axes of the recorded off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes in Fourier space to sit on top of a heterodyne carrier frequency defined as an angle between the reference beam and the object beam; applying a digital filter to cut off signals around an original origin; and then performing an inverse Fourier transform.

  10. Determination of Elastic Twist in Horizontal Axis Wind Turbines (HAWTs)

    SciTech Connect (OSTI)

    Stoddard, F.; Nelson, V.; Starcher, K.; Andrews, B.

    2006-06-01

    This report presents the results of a project at the Alternative Energy Institute (AEI) which measured and calculated the elastic twist of three representative composite horizontal-axis blades: Carter 300, Gougeon ESI 54, and UTRC 8 kW.

  11. Roger Road Reservoir Single-Axis Photovoltaic Array

    Broader source: Energy.gov [DOE]

    In this photograph, the Roger Road Reclamation Water Reservoir features a 110-kilowatt (kW) solar array. This system was built on a reservoir deck as its special design allowed for a single-axis...

  12. Dual arm master controller concept

    SciTech Connect (OSTI)

    Kuban, D.P.; Perkins, G.S.

    1984-01-01

    The Advanced Servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. 6 references, 3 figures.

  13. Plasma characteristics of single- and dual-electrode ion source systems utilized in low-energy ion extraction

    SciTech Connect (OSTI)

    Vasquez, M. R.; Tokumura, S.; Kasuya, T.; Wada, M.

    2014-02-15

    Discharge characteristics in the upstream as well as in the downstream regions of a 50-eV positive ion beam were measured along the beam axis. Single- and dual-electrode configurations made of 0.1-mm diameter tungsten wires were tested. By varying the upstream discharge parameters, the shape of the sheath edge around the extractors, which can either be planar or cylindrical, can be controlled. The sheath eventually affected the simultaneous extraction of ions and neutralizing electrons. The dual-electrode configuration at the lower discharge current, revealed a homogeneous discharge downstream. At this condition, the edge of the sheath can be inferred to be planar which allowed the uniform extraction and propagation of low-energy ions at longer distances. The dual-electrode configuration was capable of transmitting low-energy ions up to 70 mm downstream.

  14. Plasma ionization frequency, edge-to-axis density ratio, and density on axis of a cylindrical gas discharge

    SciTech Connect (OSTI)

    Palacio Mizrahi, J. H.

    2014-06-15

    A rigorous derivation of expressions, starting from the governing equations, for the ionization frequency, edge-to-axis ratio of plasma density, plasma density at the axis, and radially averaged plasma density in a cylindrical gas discharge has been obtained. The derived expressions are simple and involve the relevant parameters of the discharge: Cylinder radius, axial current, and neutral gas pressure. The found expressions account for ion inertia, ion temperature, and changes in plasma ion collisionality.

  15. Confinement of quarks in dual superconductor models

    SciTech Connect (OSTI)

    Ripka, Georges

    2005-06-14

    We review some aspects and problems of quark confinement models which are based on a dual super-conductor description of the QCD vacuum.

  16. Dual Functional Cathode Additives for Battery Technologies -...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Return to Search Dual Functional Cathode Additives for Battery Technologies Brookhaven ... activation of the cell of a lithium battery having a primary metal sulfide additive ...

  17. The Aerodynamic, Dual- Wavelength Optical Spectrometer

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Aerodynamic, Dual- Wavelength Optical Spectrometer James C. Wilson Mechanical and ... 467. * Aerodynamic Particle Sizing - Wilson J.C., Liu B.Y.H., "Aerodynamic Particle ...

  18. Electrical generation using a vertical-axis wind turbine

    SciTech Connect (OSTI)

    Clark, R.N.

    1982-12-01

    Traditionally, windmills have been of the propeller or multiblade types, both of which have their rotational axis parallel to the flow of the wind. A vertical-axis wind turbine has its rotational axis perpendicular to the flow of wind and requires no orientation to keep the rotor in the windstream. The vertical-axis wind turbine operates on the same principle as an airfoil and produces lift and drag as any airfoil. A newly designed 100-kW vertical-axis wind turbine has been operated for one year at the USDA Conservation and Production Research Laboratory, Bushland, TX. The turbine has an induction generator and supplies power to a sprinkler irrigation system with excess power being sold to the electric utility. The turbine begins producing power at 5.5 m/s windspeed and reaches its rated output of 100-kW at 15 m/s. The unit has obtained a peak efficiency of 48% at a windspeed of 8 m/s or 81% of theoretical maximum. Using 17 years of windspeed data from the National Weather Service, the annual energy output is estimated at 200,000 kWh. The unit has experienced several operational problems during its initial testing. Guy cables were enlarged to provide greater stiffness to reduce blade stress levels, lightning shorted the main contactor, and the brake system required a complete redesign and modification. The turbine was operational about 60% of the time.

  19. Measurement of a part having a known axis misalignment

    SciTech Connect (OSTI)

    Castleton, R.

    1993-05-01

    It has been shown that undetected misalignment of the axis of a part can lead to unacceptable measurement errors. For this technical note, it is assumed that the axis misalignment has been determined, and that polar sweeps are used to measure the part. The proposed polar sweeps run vertically (ignoring the axis misalignment) between a plane that is parallel to the bottom datum surface of the part and a second such plane that is close to the pole of the part. No attempt is made to correct for axis misalignment by rotation of the part during the measurement sweeps. It is apparent that the distance traveled along the measurement sweep is more than the arc length representing the actual change in elevation in the part coordinate system. It is proposed that the measurement of the part on the vertical path be used as the measurement of the part on the base longitude line. This introduces an error, {delta}{theta}, in the sensitive direction that corresponds to the arc length B-S. It is shown that this error is not significant when the axis misalignment is small.

  20. Registration of the rotation axis in X-ray tomography

    SciTech Connect (OSTI)

    Yang, Yimeng; Yang, Feifei; Hingerl, Ferdinand F.; Xiao, Xianghui; Liu, Yijin; Wu, Ziyu; Benson, Sally M.; Toney, Michael F.; Andrews, Joy C.; Pianetta, Piero A.

    2015-01-01

    There is high demand for efficient, robust and automated routines for tomographic data reduction, particularly for synchrotron data. Registration of the rotation axis in data processing is a critical step affecting the quality of the reconstruction and is not easily implemented with automation. Existing methods for calculating the center of rotation have been reviewed and an improved algorithm to register the rotation axis in tomographic data is presented. The performance of the proposed method is evaluated using synchrotron-based microtomography data on geological samples with and without artificial reduction of the signal-to-noise ratio. The proposed method improves the reconstruction quality by correcting both the tilting error and the translational offset of the rotation axis. The limitation of this promising method is also discussed.

  1. Real-time spot size camera for pulsed high-energy radiographic machines

    SciTech Connect (OSTI)

    Watson, S.A.

    1993-06-01

    The focal spot size of an x-ray source is a critical parameter which degrades resolution in a flash radiograph. For best results, a small round focal spot is required. Therefore, a fast and accurate measurement of the spot size is highly desirable to facilitate machine tuning. This paper describes two systems developed for Los Alamos National Laboratory`s Pulsed High-Energy Radiographic Machine Emitting X-rays (PHERMEX) facility. The first uses a CCD camera combined with high-brightness floors, while the second utilizes phosphor storage screens. Other techniques typically record only the line spread function on radiographic film, while systems in this paper measure the more general two-dimensional point-spread function and associated modulation transfer function in real time for shot-to-shot comparison.

  2. Real-time spot size camera for pulsed high-energy radiographic machines

    SciTech Connect (OSTI)

    Watson, S.A.

    1993-01-01

    The focal spot size of an x-ray source is a critical parameter which degrades resolution in a flash radiograph. For best results, a small round focal spot is required. Therefore, a fast and accurate measurement of the spot size is highly desirable to facilitate machine tuning. This paper describes two systems developed for Los Alamos National Laboratory's Pulsed High-Energy Radiographic Machine Emitting X-rays (PHERMEX) facility. The first uses a CCD camera combined with high-brightness floors, while the second utilizes phosphor storage screens. Other techniques typically record only the line spread function on radiographic film, while systems in this paper measure the more general two-dimensional point-spread function and associated modulation transfer function in real time for shot-to-shot comparison.

  3. Morphometric Comparison of Clavicle Outlines from 3D Bone Scans and 2D Chest Radiographs: A Short-listing Tool to Assist Radiographic Identification of Human Skeletons

    SciTech Connect (OSTI)

    Stephan, Carl N.; Amidan, Brett G.; Trease, Harold E.; Guyomarch, Pierre; Pulsipher, Trenton C.; Byrd, John E.

    2014-03-01

    This paper describes a computerized clavicle identification system, primarily designed to resolve the identities of unaccounted for US soldiers who fought in the Korean War. Elliptical Fourier analysis is used to quantify the clavicle outline shape from skeletons and postero-anterior antemortem chest radiographs to rank individuals in terms of metric distance. Similar to leading fingerprint identification systems, shortlists of the top matching candidates are extracted for subsequent human visual assessment. Two independent tests of the computerized system using 17 field-recovered skeletons and 409 chest radiographs demonstrate that true positive matches are captured within the top 5% of the sample 75% of the time. These results are outstanding given the eroded state of some field-recovered skeletons and the faintness of the 1950’s photoflurographs. These methods enhance the capability to resolve several hundred cold cases for which little circumstantial information exists and current DNA and dental record technologies cannot be applied.

  4. Method and system for dual resolution translation stage (Patent...

    Office of Scientific and Technical Information (OSTI)

    The dual resolution stage also includes an adjustable pivot block mechanically coupled to the stage assembly. The adjustable pivot block includes a pivot shaft. The dual resolution ...

  5. Development of Dual-Gated Bilayer Graphene Device Structures...

    Office of Scientific and Technical Information (OSTI)

    Development of Dual-Gated Bilayer Graphene Device Structures. Citation Details In-Document Search Title: Development of Dual-Gated Bilayer Graphene Device Structures. Abstract not ...

  6. Project Profile: Sensible Heat, Direct, Dual-Media Thermal Energy...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Sensible Heat, Direct, Dual-Media Thermal Energy Storage Module Project Profile: Sensible Heat, Direct, Dual-Media Thermal Energy Storage Module Acciona logo Acciona Solar, under ...

  7. POLICY GUIDANCE MEMORANDUM #11A Approval Process for Dual Compensation...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    POLICY GUIDANCE MEMORANDUM 11A Approval Process for Dual Compensation Waivers for Reemployed Annuitants Process to grant dual compensation (salary-offset) waivers to reemployed ...

  8. Project Profile: Indirect, Dual-Media, Phase Changing Material...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Indirect, Dual-Media, Phase Changing Material Modular Thermal Energy Storage System Project Profile: Indirect, Dual-Media, Phase Changing Material Modular Thermal Energy Storage ...

  9. Low and high Temperature Dual Thermoelectric Generation Waste...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    and high Temperature Dual Thermoelectric Generation Waste Heat Recovery System for Light-Duty Vehicles Low and high Temperature Dual Thermoelectric Generation Waste Heat Recovery System ...

  10. A survey of radiographers' confidence and self-perceived accuracy in frontline image interpretation and their continuing educational preferences

    SciTech Connect (OSTI)

    Neep, Michael J; Steffens, Tom; Owen, Rebecca; McPhail, Steven M

    2014-06-15

    The provision of a written comment on traumatic abnormalities of the musculoskeletal system detected by radiographers can assist referrers and may improve patient management, but the practice has not been widely adopted outside the United Kingdom. The purpose of this study was to investigate Australian radiographers' perceptions of their readiness for practice in a radiographer commenting system and their educational preferences in relation to two different delivery formats of image interpretation education, intensive and non-intensive. A cross-sectional web-based questionnaire was implemented between August and September 2012. Participants included radiographers with experience working in emergency settings at four Australian metropolitan hospitals. Conventional descriptive statistics, frequency histograms, and thematic analysis were undertaken. A Wilcoxon signed-rank test examined whether a difference in preference ratings between intensive and non-intensive education delivery was evident. The questionnaire was completed by 73 radiographers (68% response rate). Radiographers reported higher confidence and self-perceived accuracy to detect traumatic abnormalities than to describe traumatic abnormalities of the musculoskeletal system. Radiographers frequently reported high desirability ratings for both the intensive and the non-intensive education delivery, no difference in desirability ratings for these two formats was evident (z = 1.66, P = 0.11). Some Australian radiographers perceive they are not ready to practise in a frontline radiographer commenting system. Overall, radiographers indicated mixed preferences for image interpretation education delivered via intensive and non-intensive formats. Further research, preferably randomised trials, investigating the effectiveness of intensive and non-intensive education formats of image interpretation education for radiographers is warranted.

  11. Dual manifold heat pipe evaporator

    DOE Patents [OSTI]

    Adkins, D.R.; Rawlinson, K.S.

    1994-01-04

    An improved evaporator section is described for a dual manifold heat pipe. Both the upper and lower manifolds can have surfaces exposed to the heat source which evaporate the working fluid. The tubes in the tube bank between the manifolds have openings in their lower extensions into the lower manifold to provide for the transport of evaporated working fluid from the lower manifold into the tubes and from there on into the upper manifold and on to the condenser portion of the heat pipe. A wick structure lining the inner walls of the evaporator tubes extends into both the upper and lower manifolds. At least some of the tubes also have overflow tubes contained within them to carry condensed working fluid from the upper manifold to pass to the lower without spilling down the inside walls of the tubes. 1 figure.

  12. Dual manifold heat pipe evaporator

    DOE Patents [OSTI]

    Adkins, Douglas R. (Albuquerque, NM); Rawlinson, K. Scott (Albuquerque, NM)

    1994-01-01

    An improved evaporator section for a dual manifold heat pipe. Both the upper and lower manifolds can have surfaces exposed to the heat source which evaporate the working fluid. The tubes in the tube bank between the manifolds have openings in their lower extensions into the lower manifold to provide for the transport of evaporated working fluid from the lower manifold into the tubes and from there on into the upper manifold and on to the condenser portion of the heat pipe. A wick structure lining the inner walls of the evaporator tubes extends into both the upper and lower manifolds. At least some of the tubes also have overflow tubes contained within them to carry condensed working fluid from the upper manifold to pass to the lower without spilling down the inside walls of the tubes.

  13. Vertical-axis wind turbines -- The current status of an old technology

    SciTech Connect (OSTI)

    Berg, D.E.

    1996-12-31

    Vertical-axis wind turbine technology is not well understood, even though the earliest wind machines rotated about a vertical axis. The operating environment of a vertical-axis wind turbine is quite complex, but detailed analysis capabilities have been developed and verified over the last 30 years. Although vertical-axis technology has not been widely commercialized, it exhibits both advantages and disadvantages compared to horizontal-axis technology, and in some applications, it appears to offer significant advantages.

  14. Performance Measurements of the Injection Laser System Configured for Picosecond Scale Advanced Radiographic Capability

    SciTech Connect (OSTI)

    Haefner, L C; Heebner, J E; Dawson, J W; Fochs, S N; Shverdin, M Y; Crane, J K; Kanz, K V; Halpin, J M; Phan, H H; Sigurdsson, R J; Brewer, S W; Britten, J A; Brunton, G K; Clark, W J; Messerly, M J; Nissen, J D; Shaw, B H; Hackel, R P; Hermann, M R; Tietbohl, G L; Siders, C W; Barty, C J

    2009-10-23

    We have characterized the Advanced Radiographic Capability injection laser system and demonstrated that it meets performance requirements for upcoming National Ignition Facility fusion experiments. Pulse compression was achieved with a scaled down replica of the meter-scale grating ARC compressor and sub-ps pulse duration was demonstrated at the Joule-level.

  15. VERSATILE TWO-AXIS OPEN-LOOP SOLAR TRACKER CONTROLLER*

    SciTech Connect (OSTI)

    Ward, Christina D; Maxey, L Curt; Evans III, Boyd Mccutchen; Lapsa, Melissa Voss

    2008-01-01

    A versatile single-board controller for two-axis solar tracking applications has been developed and tested on operating solar tracking systems with over two years of field experience. The operating experience gained from the two systems and associated modifications are discussed as representative examples of the practical issues associated with implementing a new two-axis solar tracker design. In this research, open and closed loop control methods were evaluated; however, only the open loop method met the 0.125 tracking accuracy requirement and the requirement to maintain pointing accuracy in hazy and scattered cloudy skies. The open loop algorithm was finally implemented in a microcontroller-based tracking system. Methods of applying this controller hardware to different tracker geometries and hardware are discussed along with the experience gained to date.

  16. On the spin-axis dynamics of a Moonless Earth

    SciTech Connect (OSTI)

    Li, Gongjie; Batygin, Konstantin

    2014-07-20

    The variation of a planet's obliquity is influenced by the existence of satellites with a high mass ratio. For instance, Earth's obliquity is stabilized by the Moon and would undergo chaotic variations in the Moon's absence. In turn, such variations can lead to large-scale changes in the atmospheric circulation, rendering spin-axis dynamics a central issue for understanding climate. The relevant quantity for dynamically forced climate change is the rate of chaotic diffusion. Accordingly, here we re-examine the spin-axis evolution of a Moonless Earth within the context of a simplified perturbative framework. We present analytical estimates of the characteristic Lyapunov coefficient as well as the chaotic diffusion rate and demonstrate that even in absence of the Moon, the stochastic change in Earth's obliquity is sufficiently slow to not preclude long-term habitability. Our calculations are consistent with published numerical experiments and illustrate the putative system's underlying dynamical structure in a simple and intuitive manner.

  17. Sandia vertical axis wind turbines (VAWTs) demonstrate offshore advantages

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    vertical axis wind turbines (VAWTs) demonstrate offshore advantages - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy

  18. X- And y-axis driver for rotating microspheres

    DOE Patents [OSTI]

    Weinstein, Berthold W.

    1979-01-01

    Apparatus for precise control of the motion and position of microspheres for examination of their interior and/or exterior. The apparatus includes an x- and y-axis driver mechanism controlled, for example, by a minicomputer for selectively rotating microspheres retained between a pair of manipulator arms having flat, smooth end surfaces. The driver mechanism includes an apertured plate and ball arrangement which provided for coupled equal and opposite movement of the manipulator arms in two perpendicular directions.

  19. Innovative Offshore Vertical-Axis Wind Turbine Rotors

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Offshore Vertical-Axis Wind Turbine Rotors - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management

  20. Bertram Brockhouse, the Triple-axis Spectrometer, and Neutron Spectroscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Bertram Brockhouse, the Triple-axis Spectrometer, and Neutron Spectroscopy Resources with Additional Information Bertram Brockhouse Courtesy of McMaster University Bertram Brockhouse 'attended the University of British Columbia, from which he graduated in 1947 with first class honours in mathematics and physics. He entered the University of Toronto that same year ... . He obtained his Ph.D. in 1950, with a thesis entitled "The Effect of Stress and Temperature upon the Magnetic Properties of

  1. Flow augmenters for vertical-axis windmills and turbines

    SciTech Connect (OSTI)

    Evans, F.C.

    1981-03-10

    A windmill is disclosed, the windmill including a vertical shaft mounted for rotation about its longitudinal axis, a number of blades spaced circumferentially around the longitudinal axis, and being disposed generally parallel to the axis of rotation of the vertical shaft, and supporting arms extending radially outwardly from the vertical shaft for supporting the blades. The windmill also includes a first member connected to an upper end of one of the blades and defining a first surface having a leading edge with respect to the direction of movement of the blade and a trailing edge rearward of the leading edge, the leading edge being lower than the trailing edge. The first surface also includes an inside lateral edge and an outer lateral edge spaced radially outwardly from the inside lateral edge, the inside lateral edge being higher than the outer lateral edge. A second member is connected to the lower end of the blade and defines a second surface, the second surface having a leading edge with respect to the direction of movement of the blade and a trailing surface rearward of the second surface leading edge, the second surface leading edge being higher than the trailing edge. The second surface also includes an inside lateral edge and an outer lateral edge spaced radially outwardly from the second surface inside lateral edge, the second surface inside lateral edge being lower than the second surface outside lateral edge.

  2. Dual control active superconductive devices

    DOE Patents [OSTI]

    Martens, Jon S.; Beyer, James B.; Nordman, James E.; Hohenwarter, Gert K. G.

    1993-07-20

    A superconducting active device has dual control inputs and is constructed such that the output of the device is effectively a linear mix of the two input signals. The device is formed of a film of superconducting material on a substrate and has two main conduction channels, each of which includes a weak link region. A first control line extends adjacent to the weak link region in the first channel and a second control line extends adjacent to the weak link region in the second channel. The current flowing from the first channel flows through an internal control line which is also adjacent to the weak link region of the second channel. The weak link regions comprise small links of superconductor, separated by voids, through which the current flows in each channel. Current passed through the control lines causes magnetic flux vortices which propagate across the weak link regions and control the resistance of these regions. The output of the device taken across the input to the main channels and the output of the second main channel and the internal control line will constitute essentially a linear mix of the two input signals imposed on the two control lines. The device is especially suited to microwave applications since it has very low input capacitance, and is well suited to being formed of high temperature superconducting materials since all of the structures may be formed coplanar with one another on a substrate.

  3. Method of simulating spherical voids for use as a radiographic standard

    DOE Patents [OSTI]

    Foster, Billy E.

    1977-01-01

    A method of simulating small spherical voids in metal is provided. The method entails drilling or etching a hemispherical depression of the desired diameter in each of two sections of metal, the sections being flat plates or different diameter cylinders. A carbon bead is placed in one of the hemispherical voids and is used as a guide to align the second hemispherical void with that in the other plate. The plates are then bonded together with epoxy, tape or similar material and the two aligned hemispheres form a sphere within the material; thus a void of a known size has been created. This type of void can be used to simulate a pore in the development of radiographic techniques of actual voids (porosity) in welds and serve as a radiographic standard.

  4. Sandia Vertical-Axis Wind-Turbine Research Presented at Science...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Vertical-Axis Wind-Turbine Research Presented at Science of Making Torque from Wind ... Twitter Google + Vimeo GovDelivery SlideShare Sandia Vertical-Axis Wind-Turbine Research ...

  5. Sandia and Partners Complete Phase I of a Vertical-Axis Deep...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    I of a Vertical-Axis Deep-Water Offshore Turbine Study - Sandia Energy Energy Search Icon ... Sandia and Partners Complete Phase I of a Vertical-Axis Deep-Water Offshore Turbine Study ...

  6. Axis-1 diode simulations I: standard 2-inch cathode

    SciTech Connect (OSTI)

    Ekdahl, Carl [Los Alamos National Laboratory

    2011-01-11

    The standard configuration of the DARHT Axis-I diode features a 5.08-cm diameter velvet emitter mounted in the flat surface of the cathode shroud. The surface of the velvet is slightly recessed {approx}2.5 mm. This configuration produces a 1.75 kA beam when a 3.8-MV pulse is applied to the anode-cathode (AK) gap. This note addresses some of the physics of this diode through the use of finite-element simulations.

  7. Torque ripple in a Darrieus, vertical axis wind turbine

    SciTech Connect (OSTI)

    Reuter, R.C. Jr.

    1980-09-01

    Interaction between a steady wind and a rotating, Darrieus, vertical axis wind turbine produces time periodic aerodynamic loads which cause time dependent torque variations, referred to as torque ripple, to occur in the mechanical link between the turbine and the electrical generator. There is concern for the effect of torque ripple upon fatigue life of drive train components and upon power quality. An analytical solution characterizing the phenomenon of torque ripple has been obtained which is based upon a Fourier expansion of the time dependent features of the problem. Numerical results for torque ripple, some experimental data, determination of acceptable levels and methods of controlling it, are presented and discussed.

  8. Lifting surface performance analysis for horizontal axis wind turbines

    SciTech Connect (OSTI)

    Kocurek, D.

    1987-06-01

    This report describes how numerical lifting-surface theory is applied to the calculation of a horizontal-axis wind turbine's aerodynamic characteristics and performance. The report also describes how such an application is implemented as a computer program. The method evolved from rotary-wing and helicopter applications and features a detailed, prescribed wake. The wake model extends from a hovering-rotor experimental generalization to include the effect of the windmill brake state on the radial and axial displacement rates of the trailing vortex system. Performance calculations are made by coupling the lifting-surface circulation solution to a blade-element analysis that incorporates two-dimensional airfoil characteristics as functions of angle of attack and Reynolds number. Several analytical stall models are also provided to extend the airfoil characteristics beyond the limits of available data. Although this work focuses on the steady-performance problem, the method includes ways to investigate the effects of wind-shear profile, tower shadow, and off-axis shaft alignment. Correlating the method to measured wind-turbine performance, and comparing it to blade-element momentum theory calculations, validate and highlight the extreme sensitivity of predictions to the quality of early post-stall airfoil behavior.

  9. Eight Pulse Performance of DARHT Axis II - Preliminary Results

    SciTech Connect (OSTI)

    Schulze, Martin E.

    2015-12-08

    The DARHT-II accelerator produces a 1.65-kA, 17-MeV beam in a 1600-ns pulse. Standard operation of the DARHT Axis II accelerator involves extracting four short pulses from the 1.6 us long macro-pulse produced by the LIA. The four short pulses are extracted using a fast kicker in combination with a quadrupole septum magnet and then transported for several meters to a high-Z material target for conversion to x-rays for radiography. The ability of the DARHT Axis 2 kicker to produce more than the standard four pulse format has been previously demonstrated. This capability was developed to study potential risks associated with beam transport during an initial commissioning phase at low energy (8 MeV) and low current (1.0 kA).The ability of the kicker to deliver more than four pulses to the target has been realized for many years. This note describes the initial results demonstrating this capability.

  10. Feasibility and optical performance of one axis three positions sun-tracking polar-axis aligned CPCs for photovoltaic applications

    SciTech Connect (OSTI)

    Tang, Runsheng; Yu, Yamei

    2010-09-15

    A new design concept, called one axis three positions sun-tracking polar-axis aligned CPCs (3P-CPCs, in short), was proposed and theoretically studied in this work for photovoltaic applications. The proposed trough-like CPC is oriented in the polar-axis direction, and the aperture is daily adjusted eastward, southward, and westward in the morning, noon and afternoon, respectively, by rotating the CPC trough, to ensure efficient collection of beam radiation nearly all day. To investigate the optical performance of such CPCs, an analytical mathematical procedure is developed to estimate daily and annual solar gain captured by such CPCs based on extraterrestrial radiation and monthly horizontal radiation. Results show that the acceptance half-angle of 3P-CPCs is a unique parameter to determine their optical performance according to extraterrestrial radiation, and the annual solar gain stays constant if the acceptance half-angle, {theta}{sub a}, is less than one third of {omega}{sub 0,min}, the sunset hour angle in the winter solstice, otherwise decreases with the increase of {theta}{sub a}. For 3P-CPCs used in China, the annual solar gain, depending on the climatic conditions in site, decreased with the acceptance half-angle, but such decrease was slow for the case of {theta}{sub a}{<=}{omega}{sub 0,min}/3, indicating that the acceptance half-angle should be less than one third of {omega}{sub 0,min} for maximizing annual energy collection. Compared to fixed east-west aligned CPCs (EW-CPCs) with a yearly optimal acceptance half-angle, the fixed south-facing polar-axis aligned CPCs (1P-CPCs) with the same acceptance half-angle as the EW-CPCs annually collected about 65-74% of that EW-CPCs did, whereas 3P-CPCs annually collected 1.26-1.45 times of that EW-CPCs collected, indicating that 3P-CPCs were more efficient for concentrating solar radiation onto their coupling solar cells. (author)

  11. Los Alamos National Laboratory to

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to begin DARHT 2 operations January 29, 2008 Hydrodynamic testing at the frontier of science LOS ALAMOS, New Mexico, January 29, 2008- The Dual Axis Radiographic Hydrodynamic Test (DARHT) facility has officially become "dual" with authorization to begin full power operations of Axis 2, adding both new capability and higher energy to the unique accelerator facility. Los Alamos National Laboratory has received authorization from the National Nuclear Security Administration to begin

  12. Dual-domain point diffraction interferometer

    DOE Patents [OSTI]

    Naulleau, Patrick P.; Goldberg, Kenneth Alan

    2000-01-01

    A hybrid spatial/temporal-domain point diffraction interferometer (referred to as the dual-domain PS/PDI) that is capable of suppressing the scattered-reference-light noise that hinders the conventional PS/PDI is provided. The dual-domain PS/PDI combines the separate noise-suppression capabilities of the widely-used phase-shifting and Fourier-transform fringe pattern analysis methods. The dual-domain PS/PDI relies on both a more restrictive implementation of the image plane PS/PDI mask and a new analysis method to be applied to the interferograms generated and recorded by the modified PS/PDI. The more restrictive PS/PDI mask guarantees the elimination of spatial-frequency crosstalk between the signal and the scattered-light noise arising from scattered-reference-light interfering with the test beam. The new dual-domain analysis method is then used to eliminate scattered-light noise arising from both the scattered-reference-light interfering with the test beam and the scattered-reference-light interfering with the "true" pinhole-diffracted reference light. The dual-domain analysis method has also been demonstrated to provide performance enhancement when using the non-optimized standard PS/PDI design. The dual-domain PS/PDI is essentially a three-tiered filtering system composed of lowpass spatial-filtering the test-beam electric field using the more restrictive PS/PDI mask, bandpass spatial-filtering the individual interferogram irradiance frames making up the phase-shifting series, and bandpass temporal-filtering the phase-shifting series as a whole.

  13. Dual waveband compact catadioptric imaging spectrometer

    DOE Patents [OSTI]

    Chrisp, Michael P.

    2012-12-25

    A catadioptric dual waveband imaging spectrometer that covers the visible through short-wave infrared, and the midwave infrared spectral regions, dispersing the visible through shortwave infrared with a zinc selenide grating and midwave infrared with a sapphire prism. The grating and prism are at the cold stop position, enabling the pupil to be split between them. The spectra for both wavebands are focused onto the relevant sections of a single dual waveband detector. Spatial keystone distortion is controlled to less than one tenth of a pixel over the full wavelength range, facilitating the matching of the spectra in the midwave infrared with the shorter wavelength region.

  14. Combustion and Emissions Performance of Dual-Fuel Gasoline and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Combustion and Emissions Performance of Dual-Fuel Gasoline and Diesel HECC on a Multi-Cylinder Light Duty Diesel Engine Combustion and Emissions Performance of Dual-Fuel Gasoline ...

  15. A Universal Dual-Fuel Controller for OEM/Aftermarket Diesel Engineswith Comprehensive Fuel & Emission Control

    Broader source: Energy.gov [DOE]

    Presents a universal dual fuel ratio controller designed to control the fueling and emissions of dual fuel systems

  16. Nonlinear characterization of a single-axis acoustic levitator

    SciTech Connect (OSTI)

    Andrade, Marco A. B.; Ramos, Tiago S.; Okina, Fbio T. A.; Adamowski, Julio C.

    2014-04-15

    The nonlinear behavior of a 20.3 kHz single-axis acoustic levitator formed by a Langevin transducer with a concave radiating surface and a concave reflector is experimentally investigated. In this study, a laser Doppler vibrometer is applied to measure the nonlinear sound field in the air gap between the transducer and the reflector. Additionally, an electronic balance is used in the measurement of the acoustic radiation force on the reflector as a function of the distance between the transducer and the reflector. The experimental results show some effects that cannot be described by the linear acoustic theory, such as the jump phenomenon, harmonic generation, and the hysteresis effect. The influence of these nonlinear effects on the acoustic levitation of small particles is discussed.

  17. IR Spectrometer Using 90-degree Off-axis Parabolic Mirrors

    SciTech Connect (OSTI)

    Robert M. Malone, Richard, G. Hacking, Ian J. McKenna, and Daniel H. Dolan

    2008-09-02

    A gated spectrometer has been designed for real-time, pulsed infrared (IR) studies at the National Synchrotron Light ource at the Brookhaven National Laboratory. A pair of 90-degree, off-axis parabolic mirrors are used to relay the light from an entrance slit to an output IR recording camera. With an initial wavelength range of 15004500 nm required, gratings could not be used in the spectrometer because grating orders would overlap. A magnesium oxide prism, placed between these parabolic mirrors, serves as the dispersion element. The spectrometer is doubly telecentric. With proper choice of the air spacing between the prism and the second parabolic mirror, any spectral region of interest within the InSb camera arrays sensitivity region can be recorded. The wavelengths leaving the second parabolic mirror are collimated, thereby relaxing the camera positioning tolerance. To set up the instrument, two different wavelength (visible) lasers are introduced at the entrance slit and made collinear with the optical axis via flip mirrors. After dispersion by the prism, these two laser beams are directed to tick marks located on the outside housing of the gated IR camera. This provides first-order wavelength calibration for the instrument. Light that is reflected off the front prism face is coupled into a high-speed detector to verify steady radiance during the gated spectral imaging. Alignment features include tick marks on the prism and parabolic mirrors. This instrument was designed to complement singlepoint pyrometry, which provides continuous time histories of a small collection of spots from shock-heated targets.

  18. Coupled dual loop absorption heat pump

    DOE Patents [OSTI]

    Sarkisian, Paul H.; Reimann, Robert C.; Biermann, Wendell J.

    1985-01-01

    A coupled dual loop absorption system which utilizes two separate complete loops. Each individual loop operates at three temperatures and two pressures. This low temperature loop absorber and condenser are thermally coupled to the high temperature loop evaporator, and the high temperature loop condenser and absorber are thermally coupled to the low temperature generator.

  19. Modular synthesis of a dual metal-dual semiconductor nano-heterostructure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Amirav, Lilac; Oba, Fadekemi; Aloni, Shaul; Alivisatos, A. Paul

    2015-04-29

    Reported is the design and modular synthesis of a dual metal-dual semiconductor heterostructure with control over the dimensions and placement of its individual components. Analogous to molecular synthesis, colloidal synthesis is now evolving into a series of sequential synthetic procedures with separately optimized steps. Here we detail the challenges and parameters that must be considered when assembling such a multicomponent nanoparticle, and their solutions.

  20. Phonon mean free path of graphite along the c-axis

    SciTech Connect (OSTI)

    Wei, Zhiyong; Yang, Juekuan; Chen, Weiyu; Bi, Kedong; Chen, Yunfei, E-mail: yunfeichen@seu.edu.cn [Jiangsu Key Laboratory for Design and Manufacture of Micro/Nano Biomedical Instruments and School of Mechanical Engineering, Southeast University, Nanjing 210096 (China); Li, Deyu, E-mail: deyu.li@vanderbilt.edu [Department of Mechanical Engineering, Vanderbilt University, Nashville, Tennessee 37235-1592 (United States)

    2014-02-24

    Phonon transport in the c-axis direction of graphite thin films has been studied using non-equilibrium molecular dynamics (MD) simulation. The simulation results show that the c-axis thermal conductivities for films of thickness ranging from 20 to 500 atomic layers are significantly lower than the bulk value. Based on the MD data, a method is developed to construct the c-axis thermal conductivity as an accumulation function of phonon mean free path (MFP), from which we show that phonons with MFPs from 2 to 2000?nm contribute ?80% of the graphite c-axis thermal conductivity at room temperature, and phonons with MFPs larger than 100?nm contribute over 40% to the c-axis thermal conductivity. These findings indicate that the commonly believed value of just a few nanometers from the simple kinetic theory drastically underestimates the c-axis phonon MFP of graphite.

  1. Preliminayr Study on Diffraction Enhanced Radiographic Imaging for a Canine Model of Cartilage Damage

    SciTech Connect (OSTI)

    Muehleman,C.; Li, J.; Zhong, Z.

    2006-01-01

    Objective: To demonstrate the ability of a novel radiographic technique, Diffraction Enhanced Radiographic Imaging (DEI), to render high contrast images of canine knee joints for identification of cartilage lesions in situ. Methods: DEI was carried out at the X-15A beamline at Brookhaven National Laboratory on intact canine knee joints with varying levels of cartilage damage. Two independent observers graded the DE images for lesions and these grades were correlated to the gross morphological grade. Results: The correlation of gross visual grades with DEI grades for the 18 canine knee joints as determined by observer 1 (r2=0.8856, P=0.001) and observer 2 (r2=0.8818, P=0.001) was high. The overall weighted ? value for inter-observer agreement was 0.93, thus considered high agreement. Conclusion: The present study is the first study for the efficacy of DEI for cartilage lesions in an animal joint, from very early signs through erosion down to subchondral bone, representing the spectrum of cartilage changes occurring in human osteoarthritis (OA). Here we show that DEI allows the visualization of cartilage lesions in intact canine knee joints with good accuracy. Hence, DEI may be applicable for following joint degeneration in animal models of OA.

  2. Using high-intensity laser-generated energetic protons to radiograph directly driven implosions

    SciTech Connect (OSTI)

    Zylstra, A. B.; Li, C. K.; Rinderknecht, H. G.; Seguin, F. H.; Petrasso, R. D.; Stoeckl, C.; Meyerhofer, D. D.; Nilson, P.; Sangster, T. C.; Le Pape, S.; Mackinnon, A.; Patel, P.

    2012-01-15

    The recent development of petawatt-class lasers with kilojoule-picosecond pulses, such as OMEGA EP [L. Waxer et al., Opt. Photonics News 16, 30 (2005)], provides a new diagnostic capability to study inertial-confinement-fusion (ICF) and high-energy-density (HED) plasmas. Specifically, petawatt OMEGA EP pulses have been used to backlight OMEGA implosions with energetic proton beams generated through the target normal sheath acceleration (TNSA) mechanism. This allows time-resolved studies of the mass distribution and electromagnetic field structures in ICF and HED plasmas. This principle has been previously demonstrated using Vulcan to backlight six-beam implosions [A. J. Mackinnon et al., Phys. Rev. Lett. 97, 045001 (2006)]. The TNSA proton backlighter offers better spatial and temporal resolution but poorer spatial uniformity and energy resolution than previous D{sup 3}He fusion-based techniques [C. Li et al., Rev. Sci. Instrum. 77, 10E725 (2006)]. A target and the experimental design technique to mitigate potential problems in using TNSA backlighting to study full-energy implosions is discussed. The first proton radiographs of 60-beam spherical OMEGA implosions using the techniques discussed in this paper are presented. Sample radiographs and suggestions for troubleshooting failed radiography shots using TNSA backlighting are given, and future applications of this technique at OMEGA and the NIF are discussed.

  3. MHK ISDB/Instruments/AXYS HydroLevel Buoy | Open Energy Information

    Open Energy Info (EERE)

    AXYS HydroLevel Buoy < MHK ISDB Jump to: navigation, search MHK Instrumentation & Sensor Database Menu Home Search Add Instrument Add Sensor Add Company Community FAQ Help...

  4. Control system for a vertical-axis windmill

    DOE Patents [OSTI]

    Brulle, R.V.

    1981-09-03

    A vertical-axis windmill having a rotating structure is provided with a series of articulated vertical blades whose positions are controlled to maintain a constant RPM for the rotating structure, when wind speed is sufficient. A microprocessor controller is used to process information on wind speed, wind direction and RPM of the rotating structure to develop an electrical signal for establishing blade position. The preferred embodiment of the invention, when connected to a utility grid, is designed to generate 40 kilowatts of power when exposed to a 20 mile per hour wind. The control system for the windmill includes electrical blade actuators that modulate the blades of the rotating structure. Blade modulation controls the blade angle of attack, which in turn controls the RPM of the rotor. In the preferred embodiment, the microprocessor controller provides the operation logic and control functions. A wind speed sensor provides inputs to start or stop the windmill, and a wind direction sensor is used to keep the blade flip region at 90 and 270/sup 0/ to the wind. The control system is designed to maintain constant rotor RPM when wind speed is between 10 and 40 miles per hour.

  5. Adaptive upscaling with the dual mesh method

    SciTech Connect (OSTI)

    Guerillot, D.; Verdiere, S.

    1997-08-01

    The objective of this paper is to demonstrate that upscaling should be calculated during the flow simulation instead of trying to enhance the a priori upscaling methods. Hence, counter-examples are given to motivate our approach, the so-called Dual Mesh Method. The main steps of this numerical algorithm are recalled. Applications illustrate the necessity to consider different average relative permeability values depending on the direction in space. Moreover, these values could be different for the same average saturation. This proves that an a priori upscaling cannot be the answer even in homogeneous cases because of the {open_quotes}dynamical heterogeneity{close_quotes} created by the saturation profile. Other examples show the efficiency of the Dual Mesh Method applied to heterogeneous medium and to an actual field case in South America.

  6. Fabrication of dual porosity electrode structure

    DOE Patents [OSTI]

    Smith, James L.; Kucera, Eugenia H.

    1991-01-01

    A substantially entirely fibrous ceramic which may have dual porosity of both micro and macro pores. Total porosity may be 60-75% by volume. A method of spraying a slurry perpendicularly to an ambient stream of air is disclosed along with a method of removing binders without altering the fiber morphology. Adding fine ceramic particulates to the green ceramic fibers enhances the sintering characteristics of the fibers.

  7. dual-function | netl.doe.gov

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Novel Dual Functional Membrane for Controlling Carbon Dioxide Emissions from Fossil Fueled Power Plants Project No.: FG26-04NT42120 Microstructure of the composite membrane Overview of the microstructure of the composite membrane comprising of: (1) a commericially available tubular or hollow fiber ceramic support; (2) a mesoporous surfactant-templated silica sub-layer with pore size 15-50 Å; and (3) a Microporous aminosilicate gas separation membrane layer with pore size 4-10 Å. This completed

  8. Fabrication of dual porosity electrode structure

    DOE Patents [OSTI]

    Smith, J.L.; Kucera, E.H.

    1991-02-12

    A substantially entirely fibrous ceramic is described which may have dual porosity of both micro and macro pores. Total porosity may be 60-75% by volume. A method of spraying a slurry perpendicularly to an ambient stream of air is disclosed along with a method of removing binders without altering the fiber morphology. Adding fine ceramic particulates to the green ceramic fibers enhances the sintering characteristics of the fibers. 3 figures.

  9. Inorganic dual-layer microporous supported membranes

    DOE Patents [OSTI]

    Brinker, C. Jeffrey; Tsai, Chung-Yi; Lu, Yungfeng

    2003-03-25

    The present invention provides for a dual-layer inorganic microporous membrane capable of molecular sieving, and methods for production of the membranes. The inorganic microporous supported membrane includes a porous substrate which supports a first inorganic porous membrane having an average pore size of less than about 25 .ANG. and a second inorganic porous membrane coating the first inorganic membrane having an average pore size of less than about 6 .ANG.. The dual-layered membrane is produced by contacting the porous substrate with a surfactant-template polymeric sol, resulting in a surfactant sol coated membrane support. The surfactant sol coated membrane support is dried, producing a surfactant-templated polymer-coated substrate which is calcined to produce an intermediate layer surfactant-templated membrane. The intermediate layer surfactant-templated membrane is then contacted with a second polymeric sol producing a polymeric sol coated substrate which is dried producing an inorganic polymeric coated substrate. The inorganic polymeric coated substrate is then calcined producing an inorganic dual-layered microporous supported membrane in accordance with the present invention.

  10. Dose impact in radiographic lung injury following lung SBRT: Statistical analysis and geometric interpretation

    SciTech Connect (OSTI)

    Yu, Victoria; Kishan, Amar U.; Cao, Minsong; Low, Daniel; Lee, Percy; Ruan, Dan

    2014-03-15

    Purpose: To demonstrate a new method of evaluating dose response of treatment-induced lung radiographic injury post-SBRT (stereotactic body radiotherapy) treatment and the discovery of bimodal dose behavior within clinically identified injury volumes. Methods: Follow-up CT scans at 3, 6, and 12 months were acquired from 24 patients treated with SBRT for stage-1 primary lung cancers or oligometastic lesions. Injury regions in these scans were propagated to the planning CT coordinates by performing deformable registration of the follow-ups to the planning CTs. A bimodal behavior was repeatedly observed from the probability distribution for dose values within the deformed injury regions. Based on a mixture-Gaussian assumption, an Expectation-Maximization (EM) algorithm was used to obtain characteristic parameters for such distribution. Geometric analysis was performed to interpret such parameters and infer the critical dose level that is potentially inductive of post-SBRT lung injury. Results: The Gaussian mixture obtained from the EM algorithm closely approximates the empirical dose histogram within the injury volume with good consistency. The average Kullback-Leibler divergence values between the empirical differential dose volume histogram and the EM-obtained Gaussian mixture distribution were calculated to be 0.069, 0.063, and 0.092 for the 3, 6, and 12 month follow-up groups, respectively. The lower Gaussian component was located at approximately 70% prescription dose (35 Gy) for all three follow-up time points. The higher Gaussian component, contributed by the dose received by planning target volume, was located at around 107% of the prescription dose. Geometrical analysis suggests the mean of the lower Gaussian component, located at 35 Gy, as a possible indicator for a critical dose that induces lung injury after SBRT. Conclusions: An innovative and improved method for analyzing the correspondence between lung radiographic injury and SBRT treatment dose has

  11. Characterization of a multi-axis ion chamber array

    SciTech Connect (OSTI)

    Simon, Thomas A.; Kozelka, Jakub; Simon, William E.; Kahler, Darren; Li, Jonathan; Liu, Chihray

    2010-11-15

    Purpose: The aim of this work was to characterize a multi-axis ion chamber array (IC PROFILER; Sun Nuclear Corporation, Melbourne, FL USA) that has the potential to simplify the acquisition of LINAC beam data. Methods: The IC PROFILER (or panel) measurement response was characterized with respect to radiation beam properties, including dose, dose per pulse, pulse rate frequency (PRF), and energy. Panel properties were also studied, including detector-calibration stability, power-on time, backscatter dependence, and the panel's agreement with water tank measurements [profiles, fractional depth dose (FDD), and output factors]. Results: The panel's relative deviation was typically within ({+-}) 1% of an independent (or nominal) response for all properties that were tested. Notable results were (a) a detectable relative field shape change of {approx}1% with linear accelerator PRF changes; (b) a large range in backscatter thickness had a minimal effect on the measured dose distribution (typically less than 1%); (c) the error spread in profile comparison between the panel and scanning water tank (Blue Phantom, CC13; IBA Schwarzenbruck, DE) was approximately ({+-}) 0.75%. Conclusions: The ability of the panel to accurately reproduce water tank profiles, FDDs, and output factors is an indication of its abilities as a dosimetry system. The benefits of using the panel versus a scanning water tank are less setup time and less error susceptibility. The same measurements (including device setup and breakdown) for both systems took 180 min with the water tank versus 30 min with the panel. The time-savings increase as the measurement load is increased.

  12. Dual fueling of a Caterpillar 3406 diesel engine

    SciTech Connect (OSTI)

    Bell, S.R.; Midkiff, K.C.; Doughty, G.; Brett, C.E.

    1996-05-01

    A Caterpillar 3406 turbocharged diesel engine was converted to operate in a dual-fuel mode and was evaluated for performance and emission characteristics for both diesel and natural gas operation. Full load power was achieved with dual fueling without knock. Similar fuel efficiencies were obtained with dual fueling a high loads, but efficiencies were lower for low loads. Bosch smoke numbers were reduced by over 50% with dual fueling for all cases investigated. NO{sub x} emissions were found to be lower at low loads and at high speeds under high load. CO emissions were significantly increased for dual fueling while CO{sub 2} concentrations in the exhaust were reduced for dual fueling.

  13. Perona Malik anisotropic diffusion model using Peaceman Rachford scheme on digital radiographic image

    SciTech Connect (OSTI)

    Halim, Suhaila Abd; Razak, Rohayu Abd; Ibrahim, Arsmah; Manurung, Yupiter HP

    2014-06-19

    In image processing, it is important to remove noise without affecting the image structure as well as preserving all the edges. Perona Malik Anisotropic Diffusion (PMAD) is a PDE-based model which is suitable for image denoising and edge detection problems. In this paper, the Peaceman Rachford scheme is applied on PMAD to remove unwanted noise as the scheme is efficient and unconditionally stable. The capability of the scheme to remove noise is evaluated on several digital radiography weld defect images computed using MATLAB R2009a. Experimental results obtained show that the Peaceman Rachford scheme improves the image quality substantially well based on the Peak Signal to Noise Ratio (PSNR). The Peaceman Rachford scheme used in solving the PMAD model successfully removes unwanted noise in digital radiographic image.

  14. Method and system for dual resolution translation stage

    DOE Patents [OSTI]

    Halpin, John Michael

    2014-04-22

    A dual resolution translation stage includes a stage assembly operable to receive an optical element and a low resolution adjustment device mechanically coupled to the stage assembly. The dual resolution stage also includes an adjustable pivot block mechanically coupled to the stage assembly. The adjustable pivot block includes a pivot shaft. The dual resolution stage further includes a lever arm mechanically coupled to the adjustable pivot block. The lever arm is operable to pivot about the pivot shaft. The dual resolution stage additionally includes a high resolution adjustment device mechanically coupled to the lever arm and the stage assembly.

  15. ARM: AOS: Dual Column Cloud Condensation Nuclei Counter (Dataset...

    Office of Scientific and Technical Information (OSTI)

    AOS: Dual Column Cloud Condensation Nuclei Counter Authors: Derek Hageman ; Bill Behrens ; Scott Smith ; Janek Uin ; Janek Uin ; Cynthia Salwen ; Cynthia Salwen ; Annette Koontz ; ...

  16. Characterization of Dual-Fuel Reactivity Controlled Compression...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    (RCCI) Using Hydrated Ethanol and Diesel Fuel Characterization of Dual-Fuel Reactivity Controlled Compression Ignition (RCCI) Using Hydrated Ethanol and Diesel Fuel This study ...

  17. A dual mass flux framework for boundary layer convection

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A dual mass flux framework for boundary layer convection Neggers, Roel European Centre for Medium-range Weather Forecasts (ECMWF) Category: Modeling A new convective boundary layer...

  18. Dual initiation strip charge apparatus and methods for making...

    Office of Scientific and Technical Information (OSTI)

    A Dual Initiation Strip Charge (DISC) apparatus is initiated by a single initiation source and detonates a strip of explosive charge at two separate contacts. The reflection of ...

  19. Gravity Duals of Lifshitz-Like Fixed Points (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    This work can be considered a small step towards making useful dual descriptions of such critical points. Authors: Kachru, Shamit ; Stanford U., Phys. Dept. SLAC ; Liu, Xiao ; ...

  20. Dual stage active magnetic regenerator and method

    DOE Patents [OSTI]

    Pecharsky, V.K.; Gschneidner, K.A. Jr.

    1999-03-30

    A dual stage active magnetic regenerator refrigerator as well as method using the Joule-Brayton thermodynamic cycle includes a high temperature stage refrigerant comprising DyAl{sub 2} or (Dy{sub 1{minus}x}Er{sub x})Al{sub 2} where x is selected to be greater than 0 and less than about 0.3 in combination with a low temperature stage comprising (Dy{sub 1{minus}x}Er{sub x})Al{sub 2} where x is selected to be greater than about 0.5 and less than 1 to provide significantly improved refrigeration efficiency in the liquefaction of gaseous hydrogen. 17 figs.

  1. Dual stage active magnetic regenerator and method

    DOE Patents [OSTI]

    Pecharsky, Vitalij K.; Gschneidner, Jr., Karl A.

    1999-03-30

    A dual stage active magnetic regenerator refrigerator as well as method using the Joule-Brayton thermodynamic cycle includes a high temperature stage refrigerant comprising DyAl.sub.2 or (Dy.sub.1-x Er.sub.x)Al.sub.2 where x is selected to be greater than 0 and less than about 0.3 in combination with a low temperature stage comprising (Dy.sub.1-x Er.sub.x)Al.sub.2 where x is selected to be greater than about 0.5 and less than 1 to provide significantly improved refrigeration efficiency in the liquefaction of gaseous hydrogen.

  2. The Role of Anti-Phase Domains in InSb-Based Structures Grown on On-Axis and Off-Axis Ge Substrates

    SciTech Connect (OSTI)

    Debnath, M. C.; Mishima, T. D.; Santos, M. B.; Hossain, K.; Holland, O. W.

    2011-12-26

    Anti-phase domains form in InSb epilayers and InSb/Al{sub 0.20}In{sub 0.80}Sb single quantum wells when grown upon on-axis (001) Ge substrates by molecular beam epitaxy. Domain formation is partially suppressed through growth on Ge substrates with surfaces that are several degrees off the (001) or (211) axis. By using off-axis Ge substrates, room-temperature electron mobilities increased to {approx}60,000 cm{sup 2}/V-s and {approx}14,000 cm{sup 2}/V-s for a 4.0-{mu}m-thick InSb epilayer and a 25-nm InSb quantum well, respectively.

  3. Dual fuel control of a high speed turbocharged diesel engine

    SciTech Connect (OSTI)

    Few, P.C.; Sardari, P.

    1987-01-01

    The modification of a Ford 7600 turbocharged diesel engine to a dual fuel engine using methane as the supplementary fuel has been carried out. The paper describes the preliminary work of dual fuel control. Two systems are examined and their behaviour is presented.

  4. Feasibility study of a dual detector configuration concept for simultaneous megavoltage imaging and dose verification in radiotherapy

    SciTech Connect (OSTI)

    Deshpande, Shrikant; McNamara, Aimee L.; Holloway, Lois; Metcalfe, Peter; Vial, Philip

    2015-04-15

    Purpose: To test the feasibility of a dual detector concept for comprehensive verification of external beam radiotherapy. Specifically, the authors test the hypothesis that a portal imaging device coupled to a 2D dosimeter provides a system capable of simultaneous imaging and dose verification, and that the presence of each device does not significantly detract from the performance of the other. Methods: The dual detector configuration comprised of a standard radiotherapy electronic portal imaging device (EPID) positioned directly on top of an ionization-chamber array (ICA) with 2 cm solid water buildup material (between EPID and ICA) and 5 cm solid backscatter material. The dose response characteristics of the ICA and the imaging performance of the EPID in the dual detector configuration were compared to the performance in their respective reference clinical configurations. The reference clinical configurations were 6 cm solid water buildup material, an ICA, and 5 cm solid water backscatter material as the reference dosimetry configuration, and an EPID with no additional buildup or solid backscatter material as the reference imaging configuration. The dose response of the ICA was evaluated by measuring the detectors response with respect to off-axis position, field size, and transit object thickness. Clinical dosimetry performance was evaluated by measuring a range of clinical intensity-modulated radiation therapy (IMRT) beams in transit and nontransit geometries. The imaging performance of the EPID was evaluated quantitatively by measuring the contrast-to-noise ratio (CNR) and spatial resolution. Images of an anthropomorphic phantom were also used for qualitative assessment. Results: The measured off-axis and field size response with the ICA in both transit and nontransit geometries for both dual detector configuration and reference dosimetry configuration agreed to within 1%. Transit dose response as a function of object thickness agreed to within 0.5%. All

  5. Tubular ceramic-carbonate dual-phase membranes and methods of manufacture thereof

    DOE Patents [OSTI]

    Lin, Jerry Y. S.; Ortiz-Landeros, Jose; Dong, Xue-Liang

    2016-05-03

    Embodiments for a tubular ceramic-carbonate dual-phase membrane and methods for manufacturing the tubular ceramic-carbonate dual-phase membrane are disclosed.

  6. Content-based fused off-axis object illumination direct-to-digital holography

    DOE Patents [OSTI]

    Price, Jeffery R.

    2006-05-02

    Systems and methods are described for content-based fused off-axis illumination direct-to-digital holography. A method includes calculating an illumination angle with respect to an optical axis defined by a focusing lens as a function of data representing a Fourier analyzed spatially heterodyne hologram; reflecting a reference beam from a reference mirror at a non-normal angle; reflecting an object beam from an object the object beam incident upon the object at the illumination angle; focusing the reference beam and the object beam at a focal plane of a digital recorder to from the content-based off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; and digitally recording the content based off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis.

  7. Axi-dilaton gravity in D{>=}4 dimensional space-times with torsion

    SciTech Connect (OSTI)

    Cebeci, H.; Dereli, T.

    2005-01-15

    We study models of axi-dilaton gravity in space-time geometries with torsion. We discuss conformal rescaling rules in both Riemannian and non-Riemannian formulations. We give static, spherically symmetric solutions and examine their singularity behavior.

  8. Aeroelastic Modeling of Large Off-shore Vertical-axis Wind Turbines...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ... K. Dixon, C. Ferreira, C. Hofemann, G. van Bussel, and G. van Kuik, "A 3D unsteady panel method for vertical axis wind turbines," Proceedings of the European Wind Energy ...

  9. Off-axis variable focus and aberration control mirrors and method

    DOE Patents [OSTI]

    Himmer, Phillip A.; Dickensheets, David L.

    2009-02-24

    An optical element with multi-layer composites that deforms to reduce optical aberrations in off-axis optic. Methods are also described in relation to the optical element.

  10. High Current-Carrying Capability in c -Axis-Oriented Superconducting...

    Office of Scientific and Technical Information (OSTI)

    High Current-Carrying Capability in c -Axis-Oriented Superconducting MgBsub 2 Thin Films Citation Details In-Document Search Title: High Current-Carrying Capability in c ...

  11. Characterization of reactively sputtered c-axis aligned nanocrystalline InGaZnO{sub 4}

    SciTech Connect (OSTI)

    Lynch, David M.; Zhu, Bin; Ast, Dieter G.; Thompson, Michael O.; Levin, Barnaby D. A.; Muller, David A.; Greene, Raymond G.

    2014-12-29

    Crystallinity and texturing of RF sputtered c-axis aligned crystal InGaZnO{sub 4} (CAAC IGZO) thin films were quantified using X-ray diffraction techniques. Above 190?C, nanocrystalline films with an X-ray peak at 2??=?30 (009 planes) developed with increasing c-axis normal texturing up to 310?C. Under optimal conditions (310?C, 10% O{sub 2}), films exhibited a c-axis texture full-width half-maximum of 20. Cross-sectional high-resolution transmission electron microscopy confirmed these results, showing alignment variation of 9 over a 15 15?nm field of view and indicating formation of much larger aligned domains than previously reported. At higher deposition temperatures, c-axis alignment was gradually lost as polycrystalline films developed.

  12. Double-exchange selection rule for the c-axis conductivity in...

    Office of Scientific and Technical Information (OSTI)

    Double-exchange selection rule for the c-axis conductivity in layered Lasub 2-2xSrsub 1+2xMnsub 2Osub 7 single crystals below Tsub c Citation Details In-Document Search ...

  13. The Use of a Beryllium Hopkinson Bar to Characterize In-Axis and Cross-Axis Accelerometer Response in Shock Environments

    SciTech Connect (OSTI)

    Bateman, V.I.; Brown, F.A.

    1999-01-01

    The characteristics of a piezoresistive accelerometer in shock environments have been studied at Sandia National Laboratories in the Mechanical Shock Laboratory. A beryllium Hopkinson bar capability with diameters of 0.75 in. and 2.0 in has been developed to extend our understanding of the piezoresistive accelerometer, in two mechanical configurations, in the high frequency, high shock environments where measurements are being made. The in-axis performance of the piezoresistive accelerometer determined from measurements with a beryllium Hopkinson bar and a certified laser doppler vibrometer as the reference measurement is presented. The cross-axis performance of the accelerometer subjected to static compression on a beryllium cylinder, static strain on a steel beam, dynamic strain on a steel beam (ISA-RP 37.2, Paragraph 6.6), and compressive shocks in a split beryllium Hopkinson bar configuration is also presented. The performance of the accelerometer in a combined in-axis and cross-axis shock environment is shown for one configuration. Finally, a failure analysis conducted in cooperation with ENDEVCO gives a cause for the occasional unexplained failures that have occurred in some applications.

  14. Design and analysis of a vertical axis ocean current power plant

    SciTech Connect (OSTI)

    Richard, C.C.; Hartzog, J.R.; Sorge, R.V.; Quigley, J.V.; Adams, G.R.

    1981-01-01

    This paper discusses a calculation of the power generated by a vertical axis ocean current power plant. An analytical model is presented and a computer solution described. Results of the calculation show the optimum angles of the blades about the vertical axis to maximize power output, as well as the total extractable power of the plant for various ocean current velocities. Tow tank tests are described for a scale model of the plant.

  15. Method for non-contact particle manipulation and control of particle spacing along an axis

    DOE Patents [OSTI]

    Goddard, Gregory Russ; Kaduchak, Gregory; Jett, James Hubert; Graves, Steven Wayde

    2012-09-11

    Method and system for uniformly spacing particles in a flowing system comprising suspending particles in an elongated fluid filled cavity; exposing said cavity to an axial acoustic standing wave field, wherein said axial acoustic standing wave field drives said particles to nodal and anti-nodal positions along the center axis of said cavity to result in uniformly spaced particles; and focusing said particles to the center axis of said cavity.

  16. Method for non-contact particle manipulation and control of particle spacing along an axis

    DOE Patents [OSTI]

    Goddard, Gregory R; Kaduchak, Gregory; Jett, James H; Graves, Steven W

    2015-01-13

    Method and system for uniformly spacing particles in a flowing system comprising suspending particles in an elongated fluid filled cavity; exposing said cavity to an axial acoustic standing wave field, wherein said axial acoustic standing wave field drives said particles to nodal and anti-nodal positions along the center axis of said cavity to result in uniformly spaced particles; and focusing said particles to the center axis of said cavity.

  17. Evaluating radiographers' diagnostic accuracy in screen-reading mammograms: what constitutes a quality study?

    SciTech Connect (OSTI)

    Debono, Josephine C; Poulos, Ann E

    2015-03-15

    The aim of this study was to first evaluate the quality of studies investigating the diagnostic accuracy of radiographers as mammogram screen-readers and then to develop an adapted tool for determining the quality of screen-reading studies. A literature search was used to identify relevant studies and a quality evaluation tool constructed by combining the criteria for quality of Whiting, Rutjes, Dinnes et al. and Brealey and Westwood. This constructed tool was then applied to the studies and subsequently adapted specifically for use in evaluating quality in studies investigating diagnostic accuracy of screen-readers. Eleven studies were identified and the constructed tool applied to evaluate quality. This evaluation resulted in the identification of quality issues with the studies such as potential for bias, applicability of results, study conduct, reporting of the study and observer characteristics. An assessment of the applicability and relevance of the tool for this area of research resulted in adaptations to the criteria and the development of a tool specifically for evaluating diagnostic accuracy in screen-reading. This tool, with further refinement and rigorous validation can make a significant contribution to promoting well-designed studies in this important area of research and practice.

  18. A flat-cathode thermionic injector for the PHERMEX Radiographic Facility

    SciTech Connect (OSTI)

    Kauppila, T.; Builta, L.; Burns, M.; Gregory, W.; Honaberger, D.; Watson, S.; Hughes, T.

    1993-06-01

    The PHERMEX (Pulsed High-Energy Radiographic Machine Emitting X-rays) standing-wave linear accelerator is a high-current electron beam generator used for flash-radiography. An improved electron gun has been designed employing a flat-thermionic cathode to replace the existing Pierce-geometry gun. The flat cathode yields increased current with the same applied voltage and cathode area as the Pierce gun. The ISIS code simulations indicate a beam current of 1.5 kA at 600 kV. The new geometry also reduces the probability for high voltage breakdown in the A-K gap. A reentrant magnet captures the expanding electron beam and a bucking coil nulls cathode-tinge field. A third coil is used to optimize the extraction field profile and reduce the effect of nonlinear space charge on the beam emittance. Time-resolved measurements of beam current and voltage have been made. In addition, a streak camera was used to measure beam emittance and spatial profile. Comparisons of measurements with simulations are presented.

  19. A flat-cathode thermionic injector for the PHERMEX Radiographic Facility

    SciTech Connect (OSTI)

    Kauppila, T.; Builta, L.; Burns, M.; Gregory, W.; Honaberger, D.; Watson, S. ); Hughes, T. )

    1993-01-01

    The PHERMEX (Pulsed High-Energy Radiographic Machine Emitting X-rays) standing-wave linear accelerator is a high-current electron beam generator used for flash-radiography. An improved electron gun has been designed employing a flat-thermionic cathode to replace the existing Pierce-geometry gun. The flat cathode yields increased current with the same applied voltage and cathode area as the Pierce gun. The ISIS code simulations indicate a beam current of 1.5 kA at 600 kV. The new geometry also reduces the probability for high voltage breakdown in the A-K gap. A reentrant magnet captures the expanding electron beam and a bucking coil nulls cathode-tinge field. A third coil is used to optimize the extraction field profile and reduce the effect of nonlinear space charge on the beam emittance. Time-resolved measurements of beam current and voltage have been made. In addition, a streak camera was used to measure beam emittance and spatial profile. Comparisons of measurements with simulations are presented.

  20. Dual-keel electrodynamic maglev system

    DOE Patents [OSTI]

    He, J.L.; Wang, Z.; Rote, D.M.; Coffey, H.T.; Hull, J.R.; Mulcahy, T.M.; Cal, Y.

    1996-12-24

    A propulsion and stabilization system is disclosed with a plurality of superconducting magnetic devices affixed to the dual-keels of a vehicle, where the superconducting magnetic devices produce a magnetic field when energized. The system also includes a plurality of figure-eight shaped null-flux coils affixed to opposing vertical sides of slots in a guideway. The figure-eight shaped null-flux coils are vertically oriented, laterally cross-connected in parallel, longitudinally connected in series, and continue the length of the vertical slots providing levitation and guidance force. An external power source energizes the figure-eight shaped null-flux coils to create a magnetic traveling wave that interacts with the magnetic field produced by the superconducting magnets to impart motion to the vehicle. 6 figs.

  1. Dual-keel electrodynamic maglev system

    DOE Patents [OSTI]

    He, Jianliang; Wang, Zian; Rote, Donald M.; Coffey, Howard T.; Hull, John R.; Mulcahy, Thomas M.; Cal, Yigang

    1996-01-01

    A propulsion and stabilization system with a plurality of superconducting magnetic devices affixed to the dual-keels of a vehicle, where the superconducting magnetic devices produce a magnetic field when energized. The system also includes a plurality of figure-eight shaped null-flux coils affixed to opposing vertical sides of slots in a guideway. The figure-eight shaped null-flux coils are vertically oriented, laterally cross-connected in parallel, longitudinally connected in series, and continue the length of the vertical slots providing levitation and guidance force. An external power source energizes the figure-eight shaped null-flux coils to create a magnetic traveling wave that interacts with the magnetic field produced by the superconducting magnets to impart motion to the vehicle.

  2. Dual power, constant speed electric motor system

    DOE Patents [OSTI]

    Kirschbaum, H.S.

    1984-07-31

    A dual capacity permanent split capacitor electric motor system is provided with a stator having main and auxiliary windings. The main stator winding includes two winding sections which are connected in parallel with each other and across a pair of line terminals while the auxiliary winding is connected in series with a capacitor to form a circuit branch which is connected between the line terminals for operation at a first output power level. Switching means are provided to reconnect the main stator winding sections in series with each other and in series with a second capacitor to form a circuit branch which is connected between the line terminals while the stator auxiliary winding is connected directly between the line terminals for operation at a second output power level. Automatic rotation reversal occurs when the motor switches from the first to the second output power level. 6 figs.

  3. Dual power, constant speed electric motor system

    DOE Patents [OSTI]

    Kirschbaum, Herbert S.

    1984-01-01

    A dual capacity permanent split capacitor electric motor system is provided with a stator having main and auxiliary windings. The main stator winding includes two winding sections which are connected in parallel with each other and across a pair of line terminals while the auxiliary winding is connected in series with a capacitor to form a circuit branch which is connected between the line terminals for operation at a first output power level. Switching means are provided to reconnect the main stator winding sections in series with each other and in series with a second capacitor to form a circuit branch which is connected between the line terminals while the stator auxiliary winding is connected directly between the line terminals for operation at a second output power level. Automatic rotation reversal occurs when the motor switches from the first to the second output power level.

  4. Dual-fueling turbocharged diesels with ethanol

    SciTech Connect (OSTI)

    Cruz, J.M.; Rotz, C.A.; Watson, D.H.

    1982-09-01

    Spray addition and carburetion methods were tested for dual-fueling a turbocharged, 65 kW diesel tractor. Approximately 30 percent of the fuel energy for the tractor was supplied by spraying ethanol into the intake air and about 46 percent by carburetion with little affect on the engine thermal efficiency. Further substitution of diesel fuel with ethanol was limited by knock. As the amount of ethanol fed into the engine was increased, ignition apparently changed from the steady burning process which normally occurs in a diesel engine to a rapid explosion which caused knock. The best fuel for the spray approach was a 50 percent ethanol/water solution and with the carburetor it was an 80 percent ethanol/water solution.

  5. Dual-fueling turbocharged diesels with ethanol

    SciTech Connect (OSTI)

    Cruz, J.M.; Rotz, C.A.; Watson, D.H.

    1982-09-01

    Spray addition and carburetion methods were tested for dual-fueling a turbocharged, 65 kW diesel tractor. Approximately 30 percent of the fuel energy for the tractor was supplied by spraying ethanol into the intake air and about 46 percent by carburetion with little affect on the engine thermal efficiency. Further substitution of diesel fuel with ethanol was limited by knock. As the amount of ethanol fed into the engine was increased, ignition apparently changed from the steady burning process which normally occurs in a diesel engine to a rapid explosion which caused knock. The best fuel for the spray approach was a 50 percent ethanol/water solution and with the carburetor it was an 80 percent ethanol/water solution. (Refs. 6).

  6. Dual LED/incandescent security fixture

    DOE Patents [OSTI]

    Gauna, Kevin Wayne

    2005-06-21

    A dual LED and incandescent security lighting system uses a hybrid approach to LED illumination. It combines an ambient LED illuminator with a standard incandescent lamp on a motion control sensor. The LED illuminator will activate with the onset of darkness (daylight control) and typically remain on during the course of the night ("always on"). The LED illumination, typically amber, is sufficient to provide low to moderate level lighting coverage to the wall and ground area adjacent to and under the fixture. The incandescent lamp is integrated with a motion control circuit and sensor. When movement in the field of view is detected (after darkness), the incandescent lamp is switched on, providing an increased level of illumination to the area. Instead of an "always on" LED illuminator, the LEDs may also be switched off when the incandescent lamp is switched on.

  7. Dual liquid and gas chromatograph system

    DOE Patents [OSTI]

    Gay, D.D.

    A chromatographic system is described that utilizes one detection system for gas chromatographic and micro-liquid chromatographic determinations. The detection system is a direct-current, atmospheric-pressure, helium plasma emission spectrometer. The detector utilizes a nontransparent plasma source unit which contains the plasma region and two side-arms which receive effluents from the micro-liquid chromatograph and the gas chromatograph. The dual nature of this chromatographic system offers: (1) extreme flexibility in the samples to be examined; (2) extreme low sensitivity; (3) element selectivity; (4) long-term stability; (5) direct correlation of data from the liquid and gas samples; (6) simpler operation than with individual liquid and gas chromatographs, each with different detection systems; and (7) cheaper than a commercial liquid chromatograph and a gas chromatograph.

  8. Dual liquid and gas chromatograph system

    DOE Patents [OSTI]

    Gay, Don D.

    1985-01-01

    A chromatographic system that utilizes one detection system for gas chromatographic and micro-liquid chromatographic determinations. The detection system is a direct-current, atmospheric-pressure, helium plasma emission spectrometer. The detector utilizes a non-transparent plasma source unit which contains the plasma region and two side-arms which receive effluents from the micro-liquid chromatograph and the gas chromatograph. The dual nature of this chromatographic system offers: (1) extreme flexibility in the samples to be examined; (2) extremely low sensitivity; (3) element selectivity; (4) long-term stability; (5) direct correlation of data from the liquid and gas samples; (6) simpler operation than with individual liquid and gas chromatographs, each with different detection systems; and (7) cheaper than a commercial liquid chromatograph and a gas chromatograph.

  9. Microelectromechanical dual-mass resonator structure

    DOE Patents [OSTI]

    Dyck, Christopher W.; Allen, James J.; Huber, Robert J.

    2002-01-01

    A dual-mass microelectromechanical (MEM) resonator structure is disclosed in which a first mass is suspended above a substrate and driven to move along a linear or curved path by a parallel-plate electrostatic actuator. A second mass, which is also suspended and coupled to the first mass by a plurality of springs is driven by motion of the first mass. Various modes of operation of the MEM structure are possible, including resonant and antiresonant modes, and a contacting mode. In each mode of operation, the motion induced in the second mass can be in the range of several microns up to more than 50 .mu.m while the first mass has a much smaller displacement on the order of one micron or less. The MEM structure has applications for forming microsensors that detect strain, acceleration, rotation or movement.

  10. Comments on shielding for dual energy accelerators

    SciTech Connect (OSTI)

    Rossi, M. C.; Lincoln, H. M.; Quarin, D. J.; Zwicker, R. D.

    2008-06-15

    Determination of shielding requirements for medical linear accelerators has been greatly facilitated by the publication of the National Council on Radiation Protection and Measurements (NCRP) latest guidelines on this subject in NCRP Report No. 151. In the present report the authors review their own recent experience with patient treatments on conventional dual energy linear accelerators to examine the various input parameters needed to follow the NCRP guidelines. Some discussion is included of workloads, occupancy, use factors, and field size, with the effects of intensity modulated radiotherapy (IMRT) treatments included. Studies of collimator settings showed average values of 13.1x16.2 cm{sup 2} for 6 MV and 14.1x16.8 cm{sup 2} for 18 MV conventional ports, and corresponding average unblocked areas of 228 and 254 cm{sup 2}, respectively. With an average of 77% of the field area unblocked, this gives a mean irradiated area of 196 cm{sup 2} for the 18 MV beam, which dominates shielding considerations for most dual energy machines. Assuming conservatively small room dimensions, a gantry bin angle of 18 deg. was found to represent a reasonable unit for tabulation of use factors. For conventional 18 MV treatments it was found that the usual treatment angles of 0, 90, 180, and 270 deg. were still favored, and use factors of 0.25 represent reasonable estimates for these beams. As expected, the IMRT fields (all at 6 MV) showed a high degree of gantry angle randomization, with no bin having a use factor in excess of 0.10. It is concluded that unless a significant number of patients are treated with high energy IMRT, the traditional use factors of 0.25 are appropriate for the dominant high energy beam.

  11. Fused off-axis object illumination direct-to-digital holography with a plurality of illumination sources

    DOE Patents [OSTI]

    Price, Jeffery R.; Bingham, Philip R.

    2005-11-08

    Systems and methods are described for rapid acquisition of fused off-axis illumination direct-to-digital holography. A method of recording a plurality of off-axis object illuminated spatially heterodyne holograms, each of the off-axis object illuminated spatially heterodyne holograms including spatially heterodyne fringes for Fourier analysis, includes digitally recording, with a first illumination source of an interferometer, a first off-axis object illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis; and digitally recording, with a second illumination source of the interferometer, a second off-axis object illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis.

  12. Fuel reactivity effects on the efficiency and operational window of dual-fuel compression ignition engines

    SciTech Connect (OSTI)

    Splitter, Derek A; Reitz, Rolf

    2014-01-01

    Fuel reactivity effects on the efficiency and operational window of dual-fuel compression ignition engines

  13. The use of a beryllium Hopkinson bar to characterize in-axis and cross-axis accelerometer response in shock environments

    SciTech Connect (OSTI)

    Bateman, V.I.; Brown, F.A.

    1997-05-01

    The characteristics of a piezoresistive accelerometer in shock environments are being studied at Sandia National Laboratories in the Mechanical Shock Testing Laboratory. A beryllium Hopkinson bar capability has been developed to extend the understanding of the piezoresistive accelerometer, in two mechanical configurations and with and without mechanical isolation, in the high frequency, high shock environments where measurements are being made. In this paper, recent measurements with beryllium single and split-Hopkinson bar configurations are described. The in axis performance of the piezoresistive accelerometer in mechanical isolation for frequencies of dc-30 kHz and shock magnitudes of up to 6,000 g as determined from measurements with a beryllium Hopkinson bar with a certified laser doppler vibrometer as the reference measurement are presented. Results of characterizations of the accelerometers subjected to cross axis shocks in a split beryllium Hopkinson bar configuration are also presented.

  14. Microsoft Word - Defense Science Quarterly 08-08.doc

    National Nuclear Security Administration (NNSA)

    August 2008 Defense Science Quarterly Inside This Issue 1 Message from the Director 2 Derivative Applications of Pulsed Power Science and Technology 4 LANSCE-R Means More Beam for National Security Research 6 Dual Axis Radiographic Hydrodynamics Test (DARHT) 2 nd Axis Completed and Put into Operation 7 Annual Symposium of the Stewardship Science Graduate Fellowship Program 8 Publication Highlights 9 ICOPS 2008 9 Highlights and Awards Message from the Director Chris Deeney, Defense Science

  15. Microsoft Word - newletter August 2007 v5.doc

    National Nuclear Security Administration (NNSA)

    Defense Science Quarterly Newsletter August 2007 Inside This Issue 1 Message from the Director 2 THERMOS - A Small-Scale Experimental and Computational Study of Plutonium Deformation/ Damage/Failure Physics 3 Dual Axis Radiographic Hydrodynamics Test (DARHT) 2 nd Axis Achieves Full Accelerator Configuration 5 Science Campaigns Support High-Impact Basic Research 7 New Appointment and Awards Chris Deeney, Director, Office of Defense Science Welcome to the inaugural issue of the Office of Defense

  16. Slant-hole collimator, dual mode sterotactic localization method

    DOE Patents [OSTI]

    Weisenberger, Andrew G.

    2002-01-01

    The use of a slant-hole collimator in the gamma camera of dual mode stereotactic localization apparatus allows the acquisition of a stereo pair of scintimammographic images without repositioning of the gamma camera between image acquisitions.

  17. NREL: Measurements and Characterization - Dual-Beam Sample Preparation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The FIB is equipped with a gas injection system (GIS) platinum metal deposition capability ... dual beam FIB showing nano deposition with GIS of Pt contacts to a single GaN nanowire. ...

  18. York Electric Cooperative- Dual Fuel Heat Pump Rebate Program

    Broader source: Energy.gov [DOE]

    York Electric Cooperative, Inc. (YEC) offers a $200 rebate to members who install a dual fuel heat pump in homes or businesses. The rebates are for primary residences, commercial, and industrial...

  19. Parameterized reduced-order models using hyper-dual numbers....

    Office of Scientific and Technical Information (OSTI)

    This report presents a methodology for developing parameterized ROMs, which is based on Craig-Bampton component mode synthesis and the use of hyper-dual numbers to calculate the ...

  20. dual-phase-ceramic-asu | netl.doe.gov

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Pre-Combustion Carbon Dioxide Capture by a New Dual-Phase Ceramic Carbonate Membrane Reactor Project No.: DE-FE0000470 Arizona State University is developing a dual-phase, membrane-based separation device which will separate carbon dioxide (CO2) from typical water gas shift (WGS) mixture feeds and produce hydrogen, which can be introduced into the combustion turbines of integrated gasification combined cycle (IGCC) plants. The objectives of the project are experimental studies of the synthesis

  1. Project Profile: Indirect, Dual-Media, Phase Changing Material Modular

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Thermal Energy Storage System | Department of Energy Indirect, Dual-Media, Phase Changing Material Modular Thermal Energy Storage System Project Profile: Indirect, Dual-Media, Phase Changing Material Modular Thermal Energy Storage System Acciona logo Acciona Solar, under the Thermal Storage FOA, plans to design and validate a prototype and demonstrate a full-size (800 MWth) thermal energy storage (TES) system based on phase change materials (PCMs). Approach Acciona is using a test loop to

  2. Fuel cell having dual electrode anode or cathode

    DOE Patents [OSTI]

    Findl, Eugene

    1985-01-01

    A fuel cell that is characterized by including a dual electrode anode that is operable to simultaneously electro-oxidize a gaseous fuel and a liquid fuel. In alternative embodiments, a fuel cell having a single electrode anode is provided with a dual electrode cathode that is operable to simultaneously reduce a gaseous oxidant and a liquid oxidant to electro-oxidize a fuel supplied to the cell.

  3. Fuel cell having dual electrode anode or cathode

    DOE Patents [OSTI]

    Findl, E.

    1984-04-10

    A fuel cell that is characterized by including a dual electrode anode that is operable to simultaneously electro-oxidize a gaseous fuel and a liquid fuel. In alternative embodiments, a fuel cell having a single electrode anode is provided with a dual electrode cathode that is operable to simultaneously reduce a gaseous oxidant and a liquid oxidant to electro-oxidize a fuel supplied to the cell.

  4. Postmortem validation of breast density using dual-energy mammography

    SciTech Connect (OSTI)

    Molloi, Sabee Ducote, Justin L.; Ding, Huanjun; Feig, Stephen A.

    2014-08-15

    Purpose: Mammographic density has been shown to be an indicator of breast cancer risk and also reduces the sensitivity of screening mammography. Currently, there is no accepted standard for measuring breast density. Dual energy mammography has been proposed as a technique for accurate measurement of breast density. The purpose of this study is to validate its accuracy in postmortem breasts and compare it with other existing techniques. Methods: Forty postmortem breasts were imaged using a dual energy mammography system. Glandular and adipose equivalent phantoms of uniform thickness were used to calibrate a dual energy basis decomposition algorithm. Dual energy decomposition was applied after scatter correction to calculate breast density. Breast density was also estimated using radiologist reader assessment, standard histogram thresholding and a fuzzy C-mean algorithm. Chemical analysis was used as the reference standard to assess the accuracy of different techniques to measure breast composition. Results: Breast density measurements using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean algorithm, and dual energy were in good agreement with the measured fibroglandular volume fraction using chemical analysis. The standard error estimates using radiologist reader assessment, standard histogram thresholding, fuzzy C-mean, and dual energy were 9.9%, 8.6%, 7.2%, and 4.7%, respectively. Conclusions: The results indicate that dual energy mammography can be used to accurately measure breast density. The variability in breast density estimation using dual energy mammography was lower than reader assessment rankings, standard histogram thresholding, and fuzzy C-mean algorithm. Improved quantification of breast density is expected to further enhance its utility as a risk factor for breast cancer.

  5. Dual mode stereotactic localization method and application

    DOE Patents [OSTI]

    Keppel, Cynthia E.; Barbosa, Fernando Jorge; Majewski, Stanislaw

    2002-01-01

    The invention described herein combines the structural digital X-ray image provided by conventional stereotactic core biopsy instruments with the additional functional metabolic gamma imaging obtained with a dedicated compact gamma imaging mini-camera. Before the procedure, the patient is injected with an appropriate radiopharmaceutical. The radiopharmaceutical uptake distribution within the breast under compression in a conventional examination table expressed by the intensity of gamma emissions is obtained for comparison (co-registration) with the digital mammography (X-ray) image. This dual modality mode of operation greatly increases the functionality of existing stereotactic biopsy devices by yielding a much smaller number of false positives than would be produced using X-ray images alone. The ability to obtain both the X-ray mammographic image and the nuclear-based medicine gamma image using a single device is made possible largely through the use of a novel, small and movable gamma imaging camera that permits its incorporation into the same table or system as that currently utilized to obtain X-ray based mammographic images for localization of lesions.

  6. Dual excitation acoustic paramagnetic logging tool

    DOE Patents [OSTI]

    Vail, III, William B.

    1989-01-01

    New methods and apparatus are disclosed which allow measurement of the presence of oil and water in gelogical formations using a new physical effect called the Acoustic Paramagnetic Logging Effect (APLE). The presence of petroleum in formation causes a slight increase in the earth's magnetic field in the vicinity of the reservoir. This is the phenomena of paramagnetism. Application of an acoustic source to a geological formation at the Larmor frequency of the nucleous present causes the paramagnetism of the formation to disappear. This results in a decrease in the earth's magnetic field in the vicinity of the oil bearing formation. Repetitively frequency sweeping the acoustic source through the Larmor frequency of the nucleons present (approx. 2 kHz) causes an amplitude modulation of the earth's magnetic field which is a consequence of the APLE. The amplitude modulation of the earth's magnetic field is measured with an induction coil gradiometer and provides a direct measure of the amount of oil and water in the excitation zone of the formation. The phase of the signal is used to infer the longitudinal relaxation times of the fluids present, which results in the ability in general to separate oil and water and to measure the viscosity of the oil present. Such measurements may be preformed in open boreholes and in cased well bores. The Dual Excitation Acoustic Paramagnetic Logging Tool employing two acoustic sources is also described.

  7. Dual excitation acoustic paramagnetic logging tool

    DOE Patents [OSTI]

    Vail, W.B. III.

    1989-02-14

    New methods and apparatus are disclosed which allow measurement of the presence of oil and water in geological formations using a new physical effect called the Acoustic Paramagnetic Logging Effect (APLE). The presence of petroleum in formation causes a slight increase in the earth's magnetic field in the vicinity of the reservoir. This is the phenomena of paramagnetism. Application of an acoustic source to a geological formation at the Larmor frequency of the nucleons present causes the paramagnetism of the formation to disappear. This results in a decrease in the earth's magnetic field in the vicinity of the oil bearing formation. Repetitively frequency sweeping the acoustic source through the Larmor frequency of the nucleons present (approx. 2 kHz) causes an amplitude modulation of the earth's magnetic field which is a consequence of the APLE. The amplitude modulation of the earth's magnetic field is measured with an induction coil gradiometer and provides a direct measure of the amount of oil and water in the excitation zone of the formation. The phase of the signal is used to infer the longitudinal relaxation times of the fluids present, which results in the ability in general to separate oil and water and to measure the viscosity of the oil present. Such measurements may be performed in open boreholes and in cased well bores. The Dual Excitation Acoustic Paramagnetic Logging Tool employing two acoustic sources is also described. 6 figs.

  8. Dual-domain lateral shearing interferometer

    DOE Patents [OSTI]

    Naulleau, Patrick P.; Goldberg, Kenneth Alan

    2004-03-16

    The phase-shifting point diffraction interferometer (PS/PDI) was developed to address the problem of at-wavelength metrology of extreme ultraviolet (EUV) optical systems. Although extremely accurate, the fact that the PS/PDI is limited to use with coherent EUV sources, such as undulator radiation, is a drawback for its widespread use. An alternative to the PS/PDI, with relaxed coherence requirements, is lateral shearing interferometry (LSI). The use of a cross-grating, carrier-frequency configuration to characterize a large-field 4.times.-reduction EUV lithography optic is demonstrated. The results obtained are directly compared with PS/PDI measurements. A defocused implementation of the lateral shearing interferometer in which an image-plane filter allows both phase-shifting and Fourier wavefront recovery. The two wavefront recovery methods can be combined in a dual-domain technique providing suppression of noise added by self-interference of high-frequency components in the test-optic wavefront.

  9. In-Axis and Cross-Axid Accelerometer Response in Shock Environments

    SciTech Connect (OSTI)

    Bateman, V.I.; Brown, F.A.

    1999-03-10

    The characteristics of a piezoresistive accelerometer in shock environments have been studied at Sandia National Laboratories (SNL) in the Mechanical Shock Testing Laboratory for ten years The SNL Shock Laboratory has developed a capability to characterize accelerometers and other transducers with shocks aligned with the transducer's sensing axis and perpendicular to the transducer's sensing axis. This unique capability includes Hopkinson bars made of aluminum, steel, titanium, and beryllium. The bars are configured as both single and split Hopkinson bars. Four different areas that conclude this study are summarized in this paper: characterization of the cross-axis response of the accelerometer in the four environments of static compression, static strain on a beam, dynamic strain, and mechanical shock, the accelerometer's response on a titanium Hopkinson bar with two 45{degree} flats on the end of the bar; failure analysis of the accelerometer; and measurement of the accelerometer's self-generating cable response in a shock environment.

  10. A two-dimensional matrix correction for off-axis portal dose prediction errors

    SciTech Connect (OSTI)

    Bailey, Daniel W.; Kumaraswamy, Lalith; Bakhtiari, Mohammad; Podgorsak, Matthew B.

    2013-05-15

    Purpose: This study presents a follow-up to a modified calibration procedure for portal dosimetry published by Bailey et al. ['An effective correction algorithm for off-axis portal dosimetry errors,' Med. Phys. 36, 4089-4094 (2009)]. A commercial portal dose prediction system exhibits disagreement of up to 15% (calibrated units) between measured and predicted images as off-axis distance increases. The previous modified calibration procedure accounts for these off-axis effects in most regions of the detecting surface, but is limited by the simplistic assumption of radial symmetry. Methods: We find that a two-dimensional (2D) matrix correction, applied to each calibrated image, accounts for off-axis prediction errors in all regions of the detecting surface, including those still problematic after the radial correction is performed. The correction matrix is calculated by quantitative comparison of predicted and measured images that span the entire detecting surface. The correction matrix was verified for dose-linearity, and its effectiveness was verified on a number of test fields. The 2D correction was employed to retrospectively examine 22 off-axis, asymmetric electronic-compensation breast fields, five intensity-modulated brain fields (moderate-high modulation) manipulated for far off-axis delivery, and 29 intensity-modulated clinical fields of varying complexity in the central portion of the detecting surface. Results: Employing the matrix correction to the off-axis test fields and clinical fields, predicted vs measured portal dose agreement improves by up to 15%, producing up to 10% better agreement than the radial correction in some areas of the detecting surface. Gamma evaluation analyses (3 mm, 3% global, 10% dose threshold) of predicted vs measured portal dose images demonstrate pass rate improvement of up to 75% with the matrix correction, producing pass rates that are up to 30% higher than those resulting from the radial correction technique alone. As in

  11. Reconstruction of the Electron Density of Molecules with Single-Axis Alignment

    SciTech Connect (OSTI)

    Starodub, Dmitri

    2011-08-12

    Diffraction from the individual molecules of a molecular beam, aligned parallel to a single axis by a strong electric field or other means, has been proposed as a means of structure determination of individual molecules. As in fiber diffraction, all the information extractable is contained in a diffraction pattern from incidence of the diffracting beam normal to the molecular alignment axis. We present two methods of structure solution for this case. One is based on the iterative projection algorithms for phase retrieval applied to the coefficients of the cylindrical harmonic expansion of the molecular electron density. Another is the holographic approach utilizing presence of the strongly scattering reference atom for a specific molecule.

  12. Off-axis sawteeth and double-tearing reconnection in reversed magnetic shear plasmas in TFTR

    SciTech Connect (OSTI)

    Chang, Z.; Park, W.; Fredrickson, E.D.

    1996-06-01

    Off-axis sawteeth are often observed in reversed magnetic shear plasmas when the minimum safety factor q is near or below 2. Fluctuations with m/n = 2/1 (m and n are the poloidal and toroidal mode numbers) appear before and after the crashes. Detailed comparison has been made between the measured T{sub e} profile evolution during the crash and a nonlinear numerical magnetohydrodynamics (MHD) simulation. The good agreement between the observation and simulation indicates that the off-axis sawteeth are due to a double-tearing magnetic reconnection process.

  13. Rotation Angle for the Optimum Tracking of One-Axis Trackers

    SciTech Connect (OSTI)

    Marion, W. F.; Dobos, A. P.

    2013-07-01

    An equation for the rotation angle for optimum tracking of one-axis trackers is derived along with equations giving the relationships between the rotation angle and the surface tilt and azimuth angles. These equations are useful for improved modeling of the solar radiation available to a collector with tracking constraints and for determining the appropriate motor revolutions for optimum tracking.

  14. Method for non-contact particle manipulation and control of particle spacing along an axis

    DOE Patents [OSTI]

    Goddard, Gregory Russ; Kaduchak, Gregory; Jett, James Hubert; Graves, Steven Wayde

    2013-09-10

    One or more of the embodiments of the present invention provide for a method of non-contact particle manipulation and control of particle spacing along an axis which includes axial and radial acoustic standing wave fields. Particles are suspended in an aqueous solution, and this solution then flows into the cylindrical flow channel. While the solution flows through the flow channel, the outer structure of the flow channel is vibrated at a resonant frequency, causing a radial acoustic standing wave field to form inside the flow channel in the solution. These radial acoustic standing waves focus the particles suspended in the solution to the center axis of the cylindrical flow channel. At the same time, a transducer is used to create an axial acoustic standing wave field in the flow channel parallel to the axis of the flow channel. This drives the particles, which are already being focused to the center axis of the flow channel, to nodes or anti-nodes of the axial standing wave at half-wavelength intervals, depending on whether the particles are more or less dense and more or less compressible than the surrounding fluid.

  15. Effect of strain along C-axis NbS{sub 2}

    SciTech Connect (OSTI)

    Singh, Tapender Kumar, Jagdish Sastri, O. S. K. S.

    2015-05-15

    We have studied electronic properties of double layered hexagonal structure of the Niobium Di-Sulphide (2H-NbS{sub 2}) superconductor for various strains introduced along the c-axis using ab-initio calculations. The DFT calculations based on Full Potential Linearized Augmented Plane Wave (FPLAPW) method are performed using the ELK code. The total energy curve (E vs a), Density of States (DOS) and the Band structure calculations obtained in this work are matching with the earlier reports. The Pressure-Volume (P-V) diagram for 2H-NbS{sub 2} was obtained using the Equation of State(EOS) calculations, which provides the relationship between the pressure and strain applied along the c-axis. The band structures for various strains ranging from 0 percent to 10 percent along c-axis in steps of 2 percent are obtained. We note that there are increasing number of bands crossing over the Fermi energy level with increase in strain. Thus, we conclude that with increasing strain along c-axis, number of conduction bands crossing the E{sub F} increases, which gives rise to more conduction states and hence higher conductivity.

  16. DC 12m telescope. Preliminary calculations. Investigation of elevation axis position.

    SciTech Connect (OSTI)

    Guarino, V. J.; High Energy Physics

    2009-12-18

    This paper examines some simple calculations of a 2D model of a telescope in order to understand how different design parameters affect the design. For the design of a telescope it is assumed that they need a design that minimizes deflections of the dish and also minimizes the size of the motors and torques needed to rotate in elevation. A common belief is that a lighter dish and minimum counterweight is desirable. However, these calculations show this is not necessarily true. The torque needed for rotation depends on the moment of inertia and if the telescope is balanced about the elevation axis. A light dish with no CW requires that the elevation axis be several meters in front of the dish (8-9m) in order to be balanced. This is not practical from a structural point of view. If the elevation axis is only 2m in front of the dish and there is no counterweight then the telescope will be unbalanced and the toruqes required will be very high - much higher than the torques needed only to overcome inertia. A heavy dish though can act as its own counterweight and the elevation axis only has to be 2-3m in front of the dish in order to achieve a balanced telescope. Also the struts that support the camera from the dish place a load on the dish which will put a bending moment on the dish. This bending moment will deform the dish and require it to be stiffer. A counterweight structure performs two functions. First, it allows the telescope to be balanced about the elevation axis. Second, it applies a force on the dish that opposes the forces from the camera struts, thereby reducing the bending moment and deformations of the dish.

  17. Dual-Fuel Truck Fleet: Start-Up Experience

    SciTech Connect (OSTI)

    NREL

    1998-09-30

    Although dual-fuel engine technology has been in development and limited use for several years, it has only recently moved toward full-scale operational capability for heavy-duty truck applications. Unlike a bifuel engine, which has two separate fuel systems that are used one at a time, a dual-fuel engine uses two fuel systems simultaneously. One of California's South Coast Air Quality Management District (SCAQMD) current programs is a demonstration of dual-fuel engine technology in heavy-duty trucks. These trucks are being studied as part of the National Renewable Energy Laboratory's (NREL's) Alternative Fuel Truck Program. This report describes the start-up experience from the program.

  18. Exploring Avionics Using Dual Cool Jets | GE Global Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Exploring Next Generation Avionics Using Dual Cool Jets Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new window) Click to share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) Exploring Next Generation Avionics Using Dual Cool Jets Ankit Kalani 2015.08.12 Heat is a byproduct of operating electronics. If not managed properly, it can severely affect the reliability and performance of the

  19. Dual output acoustic wave sensor for molecular identification

    DOE Patents [OSTI]

    Frye, Gregory C.; Martin, Stephen J.

    1991-01-01

    A method of identification and quantification of absorbed chemical species by measuring changes in both the velocity and the attenuation of an acoustic wave traveling through a thin film into which the chemical species is sorbed. The dual output response provides two independent sensor responses from a single sensing device thereby providing twice as much information as a single output sensor. This dual output technique and analysis allows a single sensor to provide both the concentration and the identity of a chemical species or permits the number of sensors required for mixtures to be reduced by a factor of two.

  20. Dual fiber microprobe for mapping elemental distributions in biological cells

    DOE Patents [OSTI]

    Martin, Rodger C [Powell, TN; Martin, Madhavi Z [Powell, TN

    2007-07-31

    Laser-induced breakdown spectroscopy (LIBS) is applied on a microscale for in situ elemental analysis and spatial mapping in biological cells. A high power laser beam is focused onto a cell surface using a dual branching optical fiber probe for optical excitation of the cell constituents. Dual spectrometers and ICCD detectors capture the emission spectra from the excited cell(s). Repeated probing or repositioning of the laser beam with respect to the cell can provide 2-D or 3-D mapping of the cell.

  1. Dual design resistor for high voltage conditioning and transmission lines

    DOE Patents [OSTI]

    Siggins, Timothy Lynn; Murray, Charles W.; Walker, Richard L.

    2007-01-23

    A dual resistor for eliminating the requirement for two different value resistors. The dual resistor includes a conditioning resistor at a high resistance value and a run resistor at a low resistance value. The run resistor can travel inside the conditioning resistor. The run resistor is capable of being advanced by a drive assembly until an electrical path is completed through the run resistor thereby shorting out the conditioning resistor and allowing the lower resistance run resistor to take over as the current carrier.

  2. Dual role of Fe dopants in enhancing stability and charge transfer...

    Office of Scientific and Technical Information (OSTI)

    Dual role of Fe dopants in enhancing stability and charge transfer in ( Li 0.8 Fe 0.2 ) ... Title: Dual role of Fe dopants in enhancing stability and charge transfer in ( Li 0.8 Fe ...

  3. Control Strategy for a Dual Loop EGR System to Meet Euro 6 and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Control Strategy for a Dual Loop EGR System to Meet Euro 6 and Beyond Control Strategy for a Dual Loop EGR System to Meet Euro 6 and Beyond Presentation given at the 2009 DEER ...

  4. Toward large N thermal QCD from dual gravity: The heavy quarkonium...

    Office of Scientific and Technical Information (OSTI)

    Toward large N thermal QCD from dual gravity: The heavy quarkonium potential Citation Details In-Document Search Title: Toward large N thermal QCD from dual gravity: The heavy ...

  5. Development of Dual-Fuel Engine for Class 8 Applications | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Dual-Fuel Engine for Class 8 Applications Development of Dual-Fuel Engine for Class 8 Applications Highlights roadmap towards 55% brake thermal efficiency and progress to meet ...

  6. TESTING OF THE DUAL ROTARY FILTER SYSTEM

    SciTech Connect (OSTI)

    Herman, D.; Fowley, M.; Stefanko, D.

    2011-08-29

    The Savannah River National Laboratory (SRNL) installed and tested two hydraulically connected SpinTek rotary microfilter (RMF) units to determine the behavior of a multiple filter system. Both units were successfully controlled by a control scheme written in DELTA-V architecture by Savannah River Remediation (SRR) Process Control Engineering personnel. The control system was tuned to provide satisfactory response to changing conditions during the operation of the multi-filter system. Stability was maintained through the startup and shutdown of one of the filter units while the second was still in operation. The installation configuration originally proposed by the Small Colum Ion Exchange (SCIX) project of independent filter and motor mountings may be susceptible to vibration. Significant stiffening of the filter and motor mounts was required to minimize the vibration. Alignment of the motor to the filter was a challenge in this test configuration. The deployment configuration must be easy to manipulate and allow for fine adjustment. An analysis of the vibration signature of the test system identified critical speeds. Whether it corresponds to the resonance frequency of a rotor radial vibration mode that was excited by rotor unbalance is uncertain based upon the measurements. A relative motion series should be completed on the filter with the final shaft configuration to determine if the resonances exist in the final filter design. The instrumentation selected for deployment, including the concentrate discharge control valve and flow meters, performed well. Automation of the valve control integrated well with the control scheme and when used in concert with the other control variables, allowed automated control of the dual RMF system. The one area of concern with the instrumentation was the condition resulting when the filtrate flow meter operated with less than three gpm. This low flow was at the lower range of performance for the flow meter. This should not be

  7. Axi-symmetrical flow reactor for [sup 196]Hg photochemical enrichment

    DOE Patents [OSTI]

    Grossman, M.W.

    1991-04-30

    The present invention is directed to an improved photochemical reactor useful for the isotopic enrichment of a predetermined isotope of mercury, especially, [sup 196]Hg. Specifically, two axi-symmetrical flow reactors were constructed according to the teachings of the present invention. These reactors improve the mixing of the reactants during the photochemical enrichment process, affording higher yields of the desired [sup 196]Hg product. Measurements of the variation of yield (Y) and enrichment factor (E) along the flow axis of these reactors indicates very substantial improvement in process uniformity compared to previously used photochemical reactor systems. In one preferred embodiment of the present invention, the photoreactor system was built such that the reactor chamber was removable from the system without disturbing the location of either the photochemical lamp or the filter employed therewith. 10 figures.

  8. Axi-symmetrical flow reactor for .sup.196 Hg photochemical enrichment

    DOE Patents [OSTI]

    Grossman, Mark W.

    1991-01-01

    The present invention is directed to an improved photochemical reactor useful for the isotopic enrichment of a predetermined isotope of mercury, especially, .sup.196 Hg. Specifically, two axi-symmetrical flow reactors were constructed according to the teachings of the present invention. These reactors improve the mixing of the reactants during the photochemical enrichment process, affording higher yields of the desired .sup.196 Hg product. Measurements of the variation of yield (Y) and enrichment factor (E) along the flow axis of these reactors indicates very substantial improvement in process uniformity compared to previously used photochemical reactor systems. In one preferred embodiment of the present invention, the photoreactor system was built such that the reactor chamber was removable from the system without disturbing the location of either the photochemical lamp or the filter employed therewith.

  9. Single-Axis Three-Beam Amplitude Monopulse Antenna-Signal Processing Issues

    SciTech Connect (OSTI)

    Doerry, Armin W.; Bickel, Douglas L.

    2015-05-01

    Typically, when three or more antenna beams along a single axis are required, the answer has been multiple antenna phase-centers, essentially a phase-monopulse system. Such systems and their design parameters are well-reported in the literature. Less appreciated is that three or more antenna beams can also be generated in an amplitude-monopulse fashion. Consequently, design guidelines and performance analysis of such antennas is somewhat under-reported in the literature. We provide discussion herein of three beams arrayed in a single axis with an amplitude-monopulse configuration. Acknowledgements The preparation of this report is the result of an unfunded research and development activity. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administ ration under contract DE-AC04-94AL85000.

  10. Three axis vector magnet set-up for cryogenic scanning probe microscopy

    SciTech Connect (OSTI)

    Galvis, J. A.; Herrera, E.; Buendía, A.; Guillamón, I.; Vieira, S.; Suderow, H.; Azpeitia, J.; Luccas, R. F.; Munuera, C.; García-Hernandez, M.; and others

    2015-01-15

    We describe a three axis vector magnet system for cryogenic scanning probe microscopy measurements. We discuss the magnet support system and the power supply, consisting of a compact three way 100 A current source. We obtain tilted magnetic fields in all directions with maximum value of 5T along z-axis and of 1.2T for XY-plane magnetic fields. We describe a scanning tunneling microscopy-spectroscopy (STM-STS) set-up, operating in a dilution refrigerator, which includes a new high voltage ultralow noise piezodrive electronics and discuss the noise level due to vibrations. STM images and STS maps show atomic resolution and the tilted vortex lattice at 150 mK in the superconductor β-Bi{sub 2}Pd. We observe a strongly elongated hexagonal lattice, which corresponds to the projection of the tilted hexagonal vortex lattice on the surface. We also discuss Magnetic Force Microscopy images in a variable temperature insert.

  11. STATISTICAL ANALYSIS OF INTERFEROMETRIC MEASUREMENTS OF AXIS RATIOS FOR CLASSICAL Be STARS

    SciTech Connect (OSTI)

    Cyr, R. P.; Jones, C. E.; Tycner, C.

    2015-01-20

    This work presents a novel method to estimate the effective opening angle of CBe star disks from projected axis ratio measurements, obtained by interferometry using a statistical approach. A Monte Carlo scheme was used to generate a large set of theoretical axis ratios from disk models using different distributions of disk densities and opening angles. These theoretical samples were then compared to observational samples, using a two-sample Kolmogorov-Smirnov test, to determine which theoretical distribution best reproduces the observations. The results suggest that the observed ratio distributions in the K, H, and N band can best be explained by the presence of thin disks, with opening half-angles of the order of 0.°15-4.°0. Results for measurements over the Hα line point toward slightly thicker disks, 3.°7-14°, which is consistent with a flaring disk predicted by the viscous disk model.

  12. Alternative Fuels Data Center: Idaho National Laboratory Dual-Fuel Buses

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Reduce Operating Costs and Emissions Idaho National Laboratory Dual-Fuel Buses Reduce Operating Costs and Emissions to someone by E-mail Share Alternative Fuels Data Center: Idaho National Laboratory Dual-Fuel Buses Reduce Operating Costs and Emissions on Facebook Tweet about Alternative Fuels Data Center: Idaho National Laboratory Dual-Fuel Buses Reduce Operating Costs and Emissions on Twitter Bookmark Alternative Fuels Data Center: Idaho National Laboratory Dual-Fuel Buses Reduce Operating

  13. Low and high Temperature Dual Thermoelectric Generation Waste Heat Recovery System for Light-Duty Vehicles

    Office of Energy Efficiency and Renewable Energy (EERE)

    Developing a low and high temperature dual thermoelectric generation waste heat recovery system for light-duty vehicles.

  14. Crystal surface symmetry from zone-axis patterns in reflection high-energy-electron diffraction

    SciTech Connect (OSTI)

    Shannon, M.D.; Eades, J.A.; Meichle, M.E.; Turner, P.S.; Buxton, B.F.

    1984-11-26

    New experimental techniques, sensitive to crystal surface symmetry, for reflection high-energy-electron diffraction have been developed and applied to the (001) surface of MgO. The techniques map the variation of the intensity of one or more diffracted beams as a function of the incident-beam orientation. The symmetry of these surface zone-axis patterns has been studied theoretically and confirmed experimentally. The techniques are expected to provide a sensitive means of surface characterization.

  15. Method and apparatus for maintaining equilibrium in a helical axis stellarator

    DOE Patents [OSTI]

    Reiman, A.; Boozer, A.

    1984-10-31

    Apparatus for maintaining three-dimensional MHD equilibrium in a plasma contained in a helical axis stellarator includes a resonant coil system, having a configuration such that current therethrough generates a magnetic field cancelling the resonant magnetic field produced by currents driven by the plasma pressure on any given flux surface resonating with the rotational transform of another flux surface in the plasma. Current through the resonant coil system is adjusted as a function of plasma beta.

  16. Method and apparatus for maintaining equilibrium in a helical axis stellarator

    DOE Patents [OSTI]

    Reiman, Allan; Boozer, Allen

    1987-01-01

    Apparatus for maintaining three-dimensional MHD equilibrium in a plasma contained in a helical axis stellerator includes a resonant coil system, having a configuration such that current therethrough generates a magnetic field cancelling the resonant magnetic field produced by currents driven by the plasma pressure on any given flux surface resonating with the rotational transform of another flux surface in the plasma. Current through the resonant coil system is adjusted as a function of plasma beta.

  17. Terahertz electron cyclotron maser interactions with an axis-encircling electron beam

    SciTech Connect (OSTI)

    Li, G. D.; Kao, S. H.; Chang, P. C.; Chu, K. R.

    2015-04-15

    To generate terahertz radiation via the electron cyclotron maser instability, harmonic interactions are essential in order to reduce the required magnetic field to a practical value. Also, high-order mode operation is required to avoid excessive Ohmic losses. The weaker harmonic interaction and mode competition associated with an over-moded structure present challenging problems to overcome. The axis-encircling electron beam is a well-known recipe for both problems. It strengthens the harmonic interaction, as well as minimizing the competing modes. Here, we examine these advantages through a broad data base obtained for a low-power, step-tunable, gyrotron oscillator. Linear results indicate far more higher-harmonic modes can be excited with an axis-encircling electron beam than with an off-axis electron beam. However, multi-mode, time-dependent simulations reveal an intrinsic tendency for a higher-harmonic mode to switch over to a lower-harmonic mode at a high beam current or upon a rapid current rise. Methods are presented to identify the narrow windows in the parameter space for stable harmonic interactions.

  18. Annual collectible energy of a two-axis tracking flat-plate solar collector

    SciTech Connect (OSTI)

    Attalage, R.A.; Reddy, T.A. )

    1992-01-01

    A correlation for annual collectible energy of a two-axis tracking flat-plate solar collector has been developed using simulated results based on typical meteorological year (TMY) data for 26 US locations. A preliminary validation of this correlation has been carried out with data from four Australian locations. With the advent of increasing interest in photovoltaic systems, there are a number of advantages of using a two-axis flat-plate collector. Since the tracking system is generally much cheaper than the collector panel, such a mode permits the incident solar radiation to be collected more efficiently. Incidence angle effects are minimized and, moreover, contrary to concentrating collectors, such a mode enables both the diffuse and beam components of solar radiation to be collected. In tropical locations where the diffuse fraction is generally high, this may be a great advantage. The objective of this study was to develop a correlation for the annual collectible energy of a two-axis tracking flat-plate collector.

  19. Dual aperture dipole magnet with second harmonic component

    DOE Patents [OSTI]

    Praeg, W.F.

    1983-08-31

    An improved dual aperture dipole electromagnet includes a second-harmonic frequency magnetic guide field winding which surrounds first harmonic frequency magnetic guide field windings associated with each aperture. The second harmonic winding and the first harmonic windings cooperate to produce resultant magnetic waveforms in the apertures which have extended acceleration and shortened reset portions of electromagnet operation.

  20. Dual aperture dipole magnet with second harmonic component

    DOE Patents [OSTI]

    Praeg, Walter F.

    1985-01-01

    An improved dual aperture dipole electromagnet includes a second-harmonic frequency magnetic guide field winding which surrounds first harmonic frequency magnetic guide field windings associated with each aperture. The second harmonic winding and the first harmonic windings cooperate to produce resultant magnetic waveforms in the apertures which have extended acceleration and shortened reset portions of electromagnet operation.

  1. A tandem-based compact dual-energy gamma generator

    SciTech Connect (OSTI)

    Persaud, A.; Kwan, J.W.; Leitner, M.; Leung, K.N.; Ludewigt, B.; Tanaka, N.; Waldron, W.; Wilde, S.; Antolak, A.J.; Morse, D.H.; Raber, T.

    2009-11-11

    A dual-energy tandem-type gamma generator has been developed at E.O. Lawrence Berkeley National Laboratory and Sandia National Laboratories. The tandem accelerator geometry allows higher energy nuclear reactions to be reached, thereby allowing more flexible generation of MeV-energy gammas for active interrogation applications.

  2. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    DOE Patents [OSTI]

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2015-10-20

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  3. Wrought stainless steels -- Dual marking and corrosion evaluation

    SciTech Connect (OSTI)

    Kobrin, G.; Lilly, J.; MacDiarmid, J.; Moniz, B.

    1999-10-01

    Prior to the 1980s, the commonly used type 300 austenitic series stainless steels (SS) in the chemical process industry were available in two grades: those with regular carbon content (straight grades) and those with extra-low carbon content (L-grades). When welding the straight grades, it was possible to sensitize the base metal adjacent to the weld. The carbon combines with the chromium at the grain boundaries, leaving a zone depleted of chromium, below the minimum required for SS, adjacent to the grain boundaries. Even a relatively mild corrosive environment then is able to selectively attack this region along grain boundaries. The dual-marked grades (types 304/304L and 316/316L) appeared, with the carbon content of an L-grade and the strength of a straight grade. Initially, there was no national code acceptance for dual marked grades. Designers were obliged to use L-grade stress values. To get around this, people were known to grind off the unacceptable part of the dual marking designation and deliver whatever grade was initially specified. ASME International now has formally stated that dual-marked grades may be used at straight grade stresses for all product forms and piping to 1,000 F (540 C).

  4. Measurements of isocenter path characteristics of the gantry rotation axis with a smartphone application

    SciTech Connect (OSTI)

    Schiefer, H. Peters, S.; Plasswilm, L.; Ingulfsen, N.; Kluckert, J.

    2015-03-15

    Purpose: For stereotactic radiosurgery, the AAPM Report No. 54 [AAPM Task Group 42 (AAPM, 1995)] requires the overall stability of the isocenter (couch, gantry, and collimator) to be within a 1 mm radius. In reality, a rotating system has no rigid axis and thus no isocenter point which is fixed in space. As a consequence, the isocenter concept is reviewed here. It is the aim to develop a measurement method following the revised definitions. Methods: The mechanical isocenter is defined here by the point which rotates on the shortest path in the room coordinate system. The path is labeled as “isocenter path.” Its center of gravity is assumed to be the mechanical isocenter. Following this definition, an image-based and radiation-free measurement method was developed. Multiple marker pairs in a plane perpendicular to the assumed gantry rotation axis of a linear accelerator are imaged with a smartphone application from several rotation angles. Each marker pair represents an independent measuring system. The room coordinates of the isocenter path and the mechanical isocenter are calculated based on the marker coordinates. The presented measurement method is by this means strictly focused on the mechanical isocenter. Results: The measurement result is available virtually immediately following completion of measurement. When 12 independent measurement systems are evaluated, the standard deviations of the isocenter path points and mechanical isocenter coordinates are 0.02 and 0.002 mm, respectively. Conclusions: The measurement is highly accurate, time efficient, and simple to adapt. It is therefore suitable for regular checks of the mechanical isocenter characteristics of the gantry and collimator rotation axis. When the isocenter path is reproducible and its extent is in the range of the needed geometrical accuracy, it should be taken into account in the planning process. This is especially true for stereotactic treatments and radiosurgery.

  5. Testing appropriateness of small scale vertical axis windmills. Final progress report

    SciTech Connect (OSTI)

    Dengler, T.

    1984-04-26

    A comparative evaluation was performed on three vertical axis windmills; Darrieus, rotating bucket and flexible, to determine which of the three was the most practical for the homeowner to construct and use to supplement electric consumption. The design and construction of the windmills are summarized. Visual observations were made on the behavior of the windmills and an anemometer was installed for the purpose of collecting data on windmill performance in different wind velocities. Results showed that the Darrieus windmill performed best, followed closely by the flexible vane. The rotating bucket was found to be a poor performer.

  6. Three axis electronic flight motion simulator real time control system design and implementation

    SciTech Connect (OSTI)

    Gao, Zhiyuan; Miao, Zhonghua Wang, Xiaohua; Wang, Xuyong

    2014-12-15

    A three axis electronic flight motion simulator is reported in this paper including the modelling, the controller design as well as the hardware implementation. This flight motion simulator could be used for inertial navigation test and high precision inertial navigation system with good dynamic and static performances. A real time control system is designed, several control system implementation problems were solved including time unification with parallel port interrupt, high speed finding-zero method of rotary inductosyn, zero-crossing management with continuous rotary, etc. Tests were carried out to show the effectiveness of the proposed real time control system.

  7. Three-dimensional Numerical Analysis on Blade Response of Vertical Axis Tidal Current Turbine Under Operational Condition

    SciTech Connect (OSTI)

    Li, Ye; Karri, Naveen K.; Wang, Qi

    2014-04-30

    Tidal power as a large-scale renewable source of energy has been receiving significant attention recently because of its advantages over the wind and other renewal energy sources. The technology used to harvest energy from tidal current is called a tidal current turbine. Though some of the principles of wind turbine design are applicable to tidal current turbines, the design of latter ones need additional considerations like cavitation damage, corrosion etc. for the long-term reliability of such turbines. Depending up on the orientation of axis, tidal current turbines can be classified as vertical axis turbines or horizontal axis turbines. Existing studies on the vertical axis tidal current turbine focus more on the hydrodynamic aspects of the turbine rather than the structural aspects. This paper summarizes our recent efforts to study the integrated hydrodynamic and structural aspects of the vertical axis tidal current turbines. After reviewing existing methods in modeling tidal current turbines, we developed a hybrid approach that combines discrete vortex method -finite element method that can simulate the integrated hydrodynamic and structural response of a vertical axis turbine. This hybrid method was initially employed to analyze a typical three-blade vertical axis turbine. The power coefficient was used to evaluate the hydrodynamic performance, and critical deflection was considered to evaluate the structural reliability. A sensitivity analysis was also conducted with various turbine height-to-radius ratios. The results indicate that both the power output and failure probability increase with the turbine height, suggesting a necessity for optimal design. An attempt to optimize a 3-blade vertical axis turbine design with hybrid method yielded a ratio of turbine height to radius (H/R) about 3.0 for reliable maximum power output.

  8. Development and Use of the Dual-Mode Plasma Torch

    SciTech Connect (OSTI)

    Womack, R.; Shuey, M.

    2002-02-26

    After several years of development, a commercially available high-temperature treatment system has been developed and installed that treats heterogeneous low-level radioactive waste. High temperature plasma processing, unique torch design and operating features make it feasible to achieve a volume reduced, permanent, high integrity waste form while eliminating the personnel exposure and costs associated with conventional sorting, characterizing and handling. Plasma technology can also be used to treat previous conditioned waste packages that no longer meet the current acceptance criteria for final disposal. Plasma treatment can result, in many cases, in a substantial volume reduction, which lowers the final disposal costs. This paper covers the recently patented dual mode plasma torch design(1), the lessons learned that fostered its development and the advantages it brings to radioactive waste processing. This paper also provides current full scale Plasma Arc Centrifugal Treatment (PACT) project status and how the dual mode torch is being used in the PACT system.

  9. Process and apparatus for measuring degree of polarization and angle of major axis of polarized beam of light

    DOE Patents [OSTI]

    Decker, Derek E.; Toeppen, John S.

    1994-01-01

    Apparatus and process are disclosed for calibrating measurements of the phase of the polarization of a polarized beam and the angle of the polarized optical beam's major axis of polarization at a diagnostic point with measurements of the same parameters at a point of interest along the polarized beam path prior to the diagnostic point. The process is carried out by measuring the phase angle of the polarization of the beam and angle of the major axis at the point of interest, using a rotatable polarizer and a detector, and then measuring these parameters again at a diagnostic point where a compensation apparatus, including a partial polarizer, which may comprise a stack of glass plates, is disposed normal to the beam path between a rotatable polarizer and a detector. The partial polarizer is then rotated both normal to the beam path and around the axis of the beam path until the detected phase of the beam polarization equals the phase measured at the point of interest. The rotatable polarizer at the diagnostic point may then be rotated manually to determine the angle of the major axis of the beam and this is compared with the measured angle of the major axis of the beam at the point of interest during calibration. Thereafter, changes in the polarization phase, and in the angle of the major axis, at the point of interest can be monitored by measuring the changes in these same parameters at the diagnostic point.

  10. Advanced regenerator testing in the Raytheon dual-use cryocoolerr

    SciTech Connect (OSTI)

    Schaefer, B. R.; Bellis, L.; Ellis, M. J.; Conrad, T. J.

    2014-01-29

    Significant progress has been made on the Raytheon low cost space cryocooler called the Dual-Use Cryocooler (DUC). Most notably, the DUC has been integrated and tested with an advanced regenerator. The advanced regenerator is a drop-in replacement for stainless steel screens and has shown significant thermodynamic performance improvements. This paper will compare the performance of two different regenerators and explain the benefits of the advanced regenerator.

  11. Dual-phase Cr-Ta alloys for structural applications

    DOE Patents [OSTI]

    Liu, Chain T.; Brady, Michael P.; Zhu, Jiahong; Tortorelli, Peter F.

    2001-01-01

    Dual phase alloys of chromium containing 2 to 11 atomic percent tantalum with minor amounts of Mo, Cr, Ti, Y, La, Cr, Si and Ge are disclosed. These alloys contain two phases including Laves phase and Cr-rich solid solution in either eutectic structures or dispersed Laves phase particles in the Cr-rich solid solution matrix. The alloys have superior mechanical properties at high temperature and good oxidation resistance when heated to above 1000.degree. C. in air.

  12. Retractable pin dual in-line package test clip

    DOE Patents [OSTI]

    Bandzuch, Gregory S.; Kosslow, William J.

    1996-01-01

    This invention is a Dual In-Line Package (DIP) test clip for use when troubleshooting circuits containing DIP integrated circuits. This test clip is a significant improvement over existing DIP test clips in that it has retractable pins which will permit troubleshooting without risk of accidentally shorting adjacent pins together when moving probes to different pins on energized circuits or when the probe is accidentally bumped while taking measurements.

  13. Dual fuel combustion in a turbocharged diesel engine

    SciTech Connect (OSTI)

    Few, P.C.; Newlyn, H.A.

    1987-01-01

    The modification of a turbocharged diesel engine to a dual-fuel engine using methane as the supplementary fuel has been carried out. The effect of the gaseous fuel in a turbo-charged diesel engine has been investigated by means of a heat release study and a computer program already developed at Leicester Polytechnic. It is used in order to examine the rate of heat released under any operational condition.

  14. Development of a high-output dual-fuel engine

    SciTech Connect (OSTI)

    Danyluk, P.R. . Fairbanks Morse Engineering Division)

    1993-10-01

    This paper presents the results of a new dual-fuel engine development program. The engine is the largest commercially available in terms of power output (650 hp/cyl) and features very low emissions (1 g/hp-hr NO[sub x]) and excellent fuel consumption (43 percent thermal efficiency). A two-cylinder turbocharged prototype was designed and built for the initial development. Results from testing on 18-cylinder production versions are also reported.

  15. Dual ion beam assisted deposition of biaxially textured template layers

    DOE Patents [OSTI]

    Groves, James R.; Arendt, Paul N.; Hammond, Robert H.

    2005-05-31

    The present invention is directed towards a process and apparatus for epitaxial deposition of a material, e.g., a layer of MgO, onto a substrate such as a flexible metal substrate, using dual ion beams for the ion beam assisted deposition whereby thick layers can be deposited without degradation of the desired properties by the material. The ability to deposit thicker layers without loss of properties provides a significantly broader deposition window for the process.

  16. Integrated process and dual-function catalyst for olefin epoxidation

    DOE Patents [OSTI]

    Zhou, Bing (Cranbury, NJ); Rueter, Michael (Plymouth Meeting, PA)

    2003-01-01

    The invention discloses a dual-functional catalyst composition and an integrated process for production of olefin epoxides including propylene oxide by catalytic reaction of hydrogen peroxide from hydrogen and oxygen with olefin feeds such as propylene. The epoxides and hydrogen peroxide are preferably produced simultaneously in situ. The dual-functional catalyst comprises noble metal crystallites with dimensions on the nanometer scale (on the order of <1 nm to 10 nm), specially dispersed on titanium silicalite substrate particles. The dual functional catalyst catalyzes both the direct reaction of hydrogen and oxygen to generate hydrogen peroxide intermediate on the noble metal catalyst surface and the reaction of the hydrogen peroxide intermediate with the propylene feed to generate propylene oxide product. Combining both these functions in a single catalyst provides a very efficient integrated process operable below the flammability limits of hydrogen and highly selective for the production of hydrogen peroxide to produce olefin oxides such as propylene oxide without formation of undesired co-products.

  17. Simulation of winds as seen by a rotating vertical axis wind turbine blade

    SciTech Connect (OSTI)

    George, R.L.

    1984-02-01

    The objective of this report is to provide turbulent wind analyses relevant to the design and testing of Vertical Axis Wind Turbines (VAWT). A technique was developed for utilizing high-speed turbulence wind data from a line of seven anemometers at a single level to simulate the wind seen by a rotating VAWT blade. Twelve data cases, representing a range of wind speeds and stability classes, were selected from the large volume of data available from the Clayton, New Mexico, Vertical Plane Array (VPA) project. Simulations were run of the rotationally sampled wind speed relative to the earth, as well as the tangential and radial wind speeds, which are relative to the rotating wind turbine blade. Spectral analysis is used to compare and assess wind simulations from the different wind regimes, as well as from alternate wind measurement techniques. The variance in the wind speed at frequencies at or above the blade rotation rate is computed for all cases, and is used to quantitatively compare the VAWT simulations with Horizontal Axis Wind Turbine (HAWT) simulations. Qualitative comparisons are also made with direct wind measurements from a VAWT blade.

  18. Aerodynamic analysis of a 10 kW horizontal-axis windmill

    SciTech Connect (OSTI)

    Figard, R.L.

    1980-01-01

    An aerodynamic study of the performance and the flowfield in the vicinity of the rotor of a three bladed 10 kW, horizontal-axis windmill is presented. The windmill has a 6.38 m (20.92 ft) diameter rotor and is rated at 10 kW in a 13.41 m/s (44.0 fps) wind. Three basic approaches are utilized. First, field measurements of the performance and the axial velocity and turbulence behind the rotor were conducted. Second, wind tunnel tests of a 1:5 scale model were performed. Third, theoretical analyses of the windmill were made. This included performance predictions with a computerized, modified blade element (vortex theory) analysis and the development and utilization of a numerical procedure employing the full Navier-Stokes equations in axi-symmetric form to examine the wake development in detail. In that effort the rotor is modeled by an actuator disk in a uniform flow, a simple turbulence transport model based on an integrated TKE equation is applied, and the equations of motion are taken in terms of the stream function, one vorticity component, and the peripheral velocity. The results of each of the three approaches shows agreement within 10 to 15% with the other two approaches.

  19. Continuous wavelength tunable laser source with optimum positioning of pivot axis for grating

    DOE Patents [OSTI]

    Pushkarsky, Michael; Amone, David F.

    2010-06-08

    A laser source (10) for generating a continuously wavelength tunable light (12) includes a gain media (16), an optical output coupler (36F), a cavity collimator (38A), a diffraction grating (30), a grating beam (54), and a beam attacher (56). The diffraction grating (30) is spaced apart from the cavity collimator (38A) and the grating (30) cooperates with the optical output coupler (36F) to define an external cavity (32). The grating (30) includes a grating face surface (42A) that is in a grating plane (42B). The beam attacher (56) retains the grating beam (54) and allows the grating beam (54) and the grating (30) to effectively pivot about a pivot axis (33) that is located approximately at an intersection of a pivot plane (50) and the grating plane (42B). As provided herein, the diffraction grating (30) can be pivoted about the unique pivot axis (33) to move the diffraction grating (30) relative to the gain media (16) to continuously tune the lasing frequency of the external cavity (32) and the wavelength of the output light (12) so that the output light (12) is mode hop free.

  20. A multichannel magnetic probe system for analysing magnetic fluctuations in helical axis plasmas

    SciTech Connect (OSTI)

    Haskey, S. R.; Blackwell, B. D.; Seiwald, B.; Hole, M. J.; Pretty, D. G.; Howard, J.; Wach, J. [Plasma Research Laboratory, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, ACT 0200 (Australia)] [Plasma Research Laboratory, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, ACT 0200 (Australia)

    2013-09-15

    The need to understand the structure of magnetic fluctuations in H-1NF heliac [S. Hamberger et al., Fusion Technol. 17, 123 (1990)] plasmas has motivated the installation of a sixteen former, tri-axis helical magnetic probe Mirnov array (HMA). The new array complements two existing poloidal Mirnov arrays by providing polarisation information, higher frequency response, and improved toroidal resolution. The helical placement is ideal for helical axis plasmas because it positions the array as close as possible to the plasma in regions of varying degrees of favourable curvature in the magnetohydrodynamic sense, but almost constant magnetic angle. This makes phase variation with probe position near linear, greatly simplifying the analysis of the data. Several of the issues involved in the design, installation, data analysis, and calibration of this unique array are presented including probe coil design, frequency response measurements, mode number identification, orientation calculations, and mapping probe coil positions to magnetic coordinates. Details of specially designed digitally programmable pre-amplifiers, which allow gains and filters to be changed as part of the data acquisition initialisation sequence and stored with the probe signals, are also presented. The low shear heliac geometry [R. Jimnez-Gmez et al., Nucl. Fusion 51, 033001 (2011)], flexibility of the H-1NF heliac, and wealth of information provided by the HMA create a unique opportunity for detailed study of Alfvn eigenmodes, which could be a serious issue for future fusion reactors.

  1. Toluene diisocyanate: Induction of the autotaxin-lysophosphatidic acid axis and its association with airways symptoms

    SciTech Connect (OSTI)

    Broström, Julia M.; Ye, Zhi-wei; Axmon, Anna; Littorin, Margareta; Tinnerberg, Håkan; Lindh, Christian H.; Zheng, Huiyuan; Ghalali, Aram; Stenius, Ulla; Jönsson, Bo A.G.; Högberg, Johan

    2015-09-15

    Diisocyanates are industrial chemicals which have a wide range of applications in developed and developing countries. They are notorious lung toxicants and respiratory sensitizers. However, the mechanisms behind their adverse effects are not adequately characterized. Autotaxin (ATX) is an enzyme producing lysophosphatidic acid (LPA), and the ATX-LPA axis has been implicated in lung related inflammatory conditions and diseases, including allergic asthma, but not to toxicity of environmental low-molecular-weight chemicals. We investigated effects of toluene diisocyanate (TDI) on ATX induction in human lung epithelial cell models, and we correlated LPA-levels in plasma to biomarkers of TDI exposure in urine collected from workers exposed to < 5 ppb (parts per billion). Information on workers' symptoms was collected through interviews. One nanomolar TDI robustly induced ATX release within 10 min in vitro. A P2X7- and P2X4-dependent microvesicle formation was implicated in a rapid ATX release and a subsequent protein synthesis. Co-localization between purinergic receptors and ATX was documented by immunofluorescence and confocal microscopy. The release was modulated by monocyte chemoattractant protein-1 (MCP-1) and by extracellular ATP. In workers, we found a dose–response relationship between TDI exposure biomarkers in urine and LPA levels in plasma. Among symptomatic workers reporting “sneezing”, the LPA levels were higher than among non-symptomatic workers. This is the first report indicating induction of the ATX-LPA axis by an environmental low-molecular-weight chemical, and our data suggest a role for the ATX-LPA axis in TDI toxicity. - Highlights: • Human epithelial cells release autotaxin in response to 1 nM toluene diisocyanate (TDI). • The release involves P2X4 and P2X7 receptors and is modulated by ATP and MCP-1. • Lysophosphatidic acid (LPA) was measured in workers exposed to < 5 ppb TDI. • LPA in plasma correlated to TDI exposure biomarkers in

  2. Dual Integrated Appliances as an Energy and Safety Solution for Low Income

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Weatherization Webinar | Department of Energy Dual Integrated Appliances as an Energy and Safety Solution for Low Income Weatherization Webinar Dual Integrated Appliances as an Energy and Safety Solution for Low Income Weatherization Webinar Slides from the Building America webinar presented by the NorthernSTAR team. webinar_northernstar_dual_appliances_20111019.pdf (9.61 MB) More Documents & Publications Building America Expert Meeting: Recommendations for Applying Water Heaters in

  3. Combined Experiment Phase 1. [Horizontal axis wind turbines: wind tunnel testing versus field testing

    SciTech Connect (OSTI)

    Butterfield, C.P.; Musial, W.P.; Simms, D.A.

    1992-10-01

    How does wind tunnel airfoil data differ from the airfoil performance on an operating horizontal axis wind turbine (HAWT) The National Renewable Energy laboratory has been conducting a comprehensive test program focused on answering this question and understanding the basic fluid mechanics of rotating HAWT stall aerodynamics. The basic approach was to instrument a wind rotor, using an airfoil that was well documented by wind tunnel tests, and measure operating pressure distributions on the rotating blade. Based an the integrated values of the pressure data, airfoil performance coefficients were obtained, and comparisons were made between the rotating data and the wind tunnel data. Care was taken to the aerodynamic and geometric differences between the rotating and the wind tunnel models. This is the first of two reports describing the Combined Experiment Program and its results. This Phase I report covers background information such as test setup and instrumentation. It also includes wind tunnel test results and roughness testing.

  4. Theoretical and experimental power from large horizontal-axis wind turbines

    SciTech Connect (OSTI)

    Viterna, L A; Janetzke, D C

    1982-09-01

    A method for calculating the output power from large horizontal-axis wind turbines is presented. Modifications to the airfoil characteristics and the momentum portion of classical blade element-momentum theory are given that improve correlation with measured data. Improvement is particularly evident at low tip speed ratios where aerodynamic stall can occur as the blade experiences high angles of attack. Output power calculated using the modified theory is compared with measured data for several large wind turbines. These wind turbines range in size from the DOE/NASA 100 kW Mod-O (38 m rotor diameter) to the 2000 kW Mod-1 (61 m rotor diameter). The calculated results are in good agreement with measured data from these machines.

  5. Design of a Thermal Imaging Diagnostic Using 90-Degree, Off-Axis, Parabolic Mirrors

    SciTech Connect (OSTI)

    Malone, Robert M.; Becker, Steven A.; Dolan, Daniel H.; Hacking, Richard G.; Hickman, Randy J.; Kaufman, Morris I.; Stevens, Gerald D.; Turley, William D.

    2006-09-01

    Thermal imaging is an important, though challenging, diagnostic for shockwave experiments. Shock-compressed materials undergo transient temperature changes that cannot be recorded with standard (greater than ms response time) infrared detectors. A further complication arises when optical elements near the experiment are destroyed. We have designed a thermal-imaging system for studying shock temperatures produced inside a gas gun at Sandia National Laboratories. Inexpensive, diamond-turned, parabolic mirrors relay an image of the shocked target to the exterior of the gas gun chamber through a sapphire vacuum port. The 30005000-nm portion of this image is directed to an infrared camera which acquires a snapshot of the target with a minimum exposure time of 150 ns. A special mask is inserted at the last intermediate image plane, to provide dynamic thermal background recording during the event. Other wavelength bands of this image are split into high-speed detectors operating at 9001700 nm, and at 17003000 nm for timeresolved pyrometry measurements. This system incorporates 90-degree, off-axis parabolic mirrors, which can collect low f/# light over a broad spectral range, for high-speed imaging. Matched mirror pairs must be used so that aberrations cancel. To eliminate image plane tilt, proper tip-to-tip orientation of the parabolic mirrors is required. If one parabolic mirror is rotated 180 degrees about the optical axis connecting the pair of parabolic mirrors, the resulting image is tilted by 60 degrees. Different focal-length mirrors cannot be used to magnify the image without substantially sacrificing image quality. This paper analyzes performance and aberrations of this imaging diagnostic.

  6. The Power of Integrators, Financiers, and Insurers to Reduce Proliferation Risks: Nuclear Dual-Use Goods

    SciTech Connect (OSTI)

    Weise, Rachel A.; Hund, Gretchen

    2015-05-01

    Globalization of manufacturing supply chains has changed the nature of nuclear proliferation. Before 1991, nonproliferation efforts focused almost exclusively on limiting the spread of materials and equipment specifically designed for nuclear use -- reactors, centrifuges, and fissile material. Dual-use items, those items with both nuclear and non-nuclear applications, were not closely scrutinized or controlled. However, in 1991 the international community discovered that Iraq had developed a fairly sophisticated nuclear weapons program by importing dual-use items; this discovery spurred the international community to increase controls on dual-use technologies. Despite these international efforts, dual-use items are still a challenge for those seeking to limit proliferation.

  7. Dual Exchange in PCN-333: A Facile Strategy to Chemically Robust...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dual Exchange in PCN-333: A Facile Strategy to Chemically Robust Mesoporous Chromium Metal-Organic Framework with Functional Groups Previous Next List Park, Jihye; Feng, Dawei; ...

  8. NREL and CSEM Jointly Set New Efficiency Record with Dual-Junction...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NREL and CSEM Jointly Set New Efficiency Record with Dual-Junction Solar Cell January 5, 2016 Scientists at the Energy Department's National Renewable Energy Laboratory (NREL) and...

  9. POLICY GUIDANCE MEMORANDUM #11A Approval Process for Dual Compensation Waivers for Reemployed Annuitants

    Broader source: Energy.gov [DOE]

    Process to  grant dual compensation (salary-offset) waivers to reemployed annuitants who work on a limited basis without reduction to their retirement annuity.

  10. NREL and CSEM Jointly Set New Efficiency Record with Dual-Junction...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NREL and CSEM Jointly Set New Efficiency Record with Dual-Junction Solar Cell January 5, 2016 Scientists at the Energy Department's National Renewable Energy Laboratory (NREL) and ...

  11. Single line-of-sight dual energy backlighter for mix width experiments

    SciTech Connect (OSTI)

    Baker, K. L. Glendinning, S. G.; Martinez, D.; Dittrich, T. R.; MacLaren, S. A.; Felker, S.; Seugling, R.; Doane, D.; Wallace, R.; Guymer, T. M.; Moore, A. S.; Whiting, N.; Sorce, C.

    2014-11-15

    We present a diagnostic technique used to spatially multiplex two x-ray radiographs of an object onto a detector along a single line-of-sight. This technique uses a thin, <2 μm, cosputtered backlighter target to simultaneously produce both Ni and Zn He{sub α} emission. A Ni picket fence filter, 500 μm wide bars and troughs, is then placed in front of the detector to pass only the Ni He{sub α} emission in the bar region and both energies in the trough region thereby spatially multiplexing the two radiographs on a single image. Initial experimental results testing the backlighter spectrum are presented along with simulated images showing the calculated radiographic images though the nickel picket fence filter which are used to measure the mix width in an accelerated nickel foam.

  12. Dual-circuit, multiple-effect refrigeration system and method

    DOE Patents [OSTI]

    DeVault, Robert C.

    1995-01-01

    A dual circuit absorption refrigeration system comprising a high temperature single-effect refrigeration loop and a lower temperature double-effect refrigeration loop separate from one another and provided with a double-condenser coupling therebetween. The high temperature condenser of the single-effect refrigeration loop is double coupled to both of the generators in the double-effect refrigeration loop to improve internal heat recovery and a heat and mass transfer additive such as 2-ethyl-1-hexanol is used in the lower temperature double-effect refrigeration loop to improve the performance of the absorber in the double-effect refrigeration loop.

  13. Dual-wavelength InP quantum dot lasers

    SciTech Connect (OSTI)

    Shutts, S.; Smowton, P. M.; Krysa, A. B.

    2014-06-16

    We have demonstrated a two-section dual-wavelength diode laser incorporating distributed Bragg reflectors, with a peak-wavelength separation of 62.5?nm at 300?K. Each lasing wavelength has a different temperature dependence, providing a difference-tuning of 0.11?nm/K. We discuss the mechanisms governing the light output of the two competing modes and explain how the short wavelength can be relatively insensitive to output changes at the longer wavelength. Starting from an initial condition when the output at both wavelengths are equal, a 500% increase in the long wavelength output causes the short wavelength output to fall by only 6%.

  14. Dual-frequency glow discharges in atmospheric helium

    SciTech Connect (OSTI)

    Huang, Xiaojiang; Guo, Ying; Dai, Lu; Zhang, Jing; Shi, J. J.

    2015-10-15

    In this paper, the dual-frequency (DF) glow discharges in atmospheric helium were experimented by electrical and optical measurements in terms of current voltage characteristics and optical emission intensity. It is shown that the waveforms of applied voltages or discharge currents are the results of low frequency (LF) waveforms added to high frequency (HF) waveforms. The HF mainly influences discharge currents, and the LF mainly influences applied voltages. The gas temperatures of DF discharges are mainly affected by HF power rather than LF power.

  15. Exclusive J/{psi} electroproduction in a dual model

    SciTech Connect (OSTI)

    Fiore, R.; Jenkovszky, L. L.; Magas, V. K.; Melis, S.; Prokudin, A.

    2009-12-01

    Exclusive J/{psi} electroproduction is studied in the framework of the analytic S-matrix theory. The differential and integrated elastic cross sections are calculated using the modified dual amplitude with Mandelstam analyticity model. The model is applied to the description of the available experimental data and proves to be valid in a wide region of the kinematical variables s, t, and Q{sup 2}. Our amplitude can be used also as a universal background parametrization for the extraction of tiny resonance signals.

  16. Gauge theories on hyperbolic spaces and dual wormhole instabilities

    SciTech Connect (OSTI)

    Buchel, Alex

    2004-09-15

    We study supergravity duals of strongly coupled four-dimensional gauge theories formulated on compact quotients of hyperbolic spaces. The resulting background geometries are represented by Euclidean wormholes, which complicate establishing the precise gauge theory/string theory correspondence dictionary. These backgrounds suffer from the nonperturbative instabilities arising from the D3D3-bar pair-production in the background four-form potential. We discuss conditions for suppressing this Schwingerlike instability. We find that Euclidean wormholes arising in this construction develop a naked singularity before they can be stabilized.

  17. Science Facilities

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Facilities Science Facilities The focal point for basic and applied R&D programs with a primary focus on energy but also encompassing medical, biotechnology, high-energy physics, and advanced scientific computing programs. Center for Integrated Nanotechnologies» Dual Axis Radiographic Hydrodynamic Test Facility (DARHT)» Electron Microscopy Lab» Ion Beam Materials Lab» Isotope Production Facility» Los Alamos Neutron Science Center» Lujan Center» Matter-Radiation Interactions in

  18. How DARHT Works - the World's Most Powerful X-ray Machine

    ScienceCinema (OSTI)

    None

    2014-06-25

    The Dual Axis Radiographic Hydrodynamic Test (DARHT) facility at Los Alamos National Laboratory is an essential scientific tool that supports Stockpile Stewardship at the Laboratory. The World's most powerful x-ray machine, it's used to take high-speed images of mock nuclear devices - data that is used to confirm and modify advanced computer codes in assuring the safety, security, and effectiveness of the U.S. nuclear deterrent.

  19. An algorithm to unveil the inner structure of objects concealed by beam divergence in radiographic image acquisition systems

    SciTech Connect (OSTI)

    Almeida, G. L.; Silvani, M. I.; Lopes, R. T.

    2014-11-11

    Two main parameters rule the performance of an Image Acquisition System, namely, spatial resolution and contrast. For radiographic systems using cone beam arrangements, the farther the source, the better the resolution, but the contrast would diminish due to the lower statistics. A closer source would yield a higher contrast but it would no longer reproduce the attenuation map of the object, as the incoming beam flux would be reduced by unequal large divergences and attenuation factors. This work proposes a procedure to correct these effects when the object is comprised of a hull - or encased in it - possessing a shape capable to be described in analytical geometry terms. Such a description allows the construction of a matrix containing the attenuation factors undergone by the beam from the source until its final destination at each coordinate on the 2D detector. Each matrix element incorporates the attenuation suffered by the beam after its travel through the hull wall, as well as its reduction due to the square of distance to the source and the angle it hits the detector surface. When the pixel intensities of the original image are corrected by these factors, the image contrast, reduced by the overall attenuation in the exposure phase, are recovered, allowing one to see details otherwise concealed due to the low contrast. In order to verify the soundness of this approach, synthetic images of objects of different shapes, such as plates and tubes, incorporating defects and statistical fluctuation, have been generated, recorded for further comparison and afterwards processed to improve their contrast. The developed algorithm which, generates processes and plots the images has been written in Fortran 90 language. As the resulting final images exhibit the expected improvements, it therefore seemed worthwhile to carry out further tests with actual experimental radiographies.

  20. Does SEGUE/SDSS indicate a dual galactic halo?

    SciTech Connect (OSTI)

    Schönrich, Ralph; Asplund, Martin; Casagrande, Luca

    2014-05-01

    We re-examine recent claims of observational evidence for a dual Galactic halo in SEGUE/SDSS data, and trace them back to improper error treatment and neglect of selection effects. In particular, the detection of a vertical abundance gradient in the halo can be explained as a metallicity bias in distance. A similar bias and the impact of disk contamination affect the sample of blue horizontal branch stars. These examples highlight why non-volume complete samples require forward modeling from theoretical models or extensive bias-corrections. We also show how observational uncertainties produce the specific non-Gaussianity in the observed azimuthal velocity distribution of halo stars, which can be erroneously identified as two Gaussian components. A single kinematic component yields an excellent fit to the observed data, when we model the measurement process including distance uncertainties. Furthermore, we show that sample differences in proper motion space are the direct consequence of kinematic cuts and are enhanced when distance estimates are less accurate. Thus, their presence is neither proof of a separate population nor a measure of reliability for the applied distances. We conclude that currently there is no evidence from SEGUE/SDSS that would favor a dual Galactic halo over a single halo that is full of substructure.

  1. Dual-purpose desalting, RO versus MSF an economic comparison

    SciTech Connect (OSTI)

    Brandt, D.C.; Battey, R.F.

    1983-01-01

    Capital and annual operating costs are estimated for producing water using three combinations of seawater reverse osmosis and gas turbines. The costs and operating parameters were developed for Middle East conditions assuming a Red Sea water source. The plants were designed to produce 37,850 m/sup 3//d (10 mgd) of potable water and to export 50,000 kW of power. The reverse osmosis plant utilizes energy recovery and was designed with full pretreatment for a surface water supply. Electricity is provided by either gas turbines, steam turbines, or combined cycle plants. Power and water costs developed for these systems were compared to costs for conventional, dual-purpose MSF/steam turbine plants for the same water and power production. These evaluations considered two levels of fuel costs. The results of this study show the significant effect of fuel costs on process selection and on water and power costs. Capital and operating costs were 20 to 28 percent less and 23 to 33 percent less, respectively, for the RO/gas turbine and RO/combined cycle plants as compared to conventional, dual-purpose MSF steam turbine plants. In addition to economics, the merits of the systems are discussed relative to delivery, ease and flexibility of operation, turndown capability, and so forth.

  2. The ArvinMeritor Dual Mode Hybrid Powertrain (DMHP): Opportunities and

    Broader source: Energy.gov (indexed) [DOE]

    Potential for Systems Optimization | Department of Energy 2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation vss062_smith_2011_p.pdf (685.41 KB) More Documents & Publications Vehicle Systems Integration (VSI) Research Laboratory at ORNL The Meritor Dual Mode Hybrid Powertrain CRADA The Meritor Dual Mode Hybrid Powertrain CRADA

  3. Development of a multi-resource alternate energy facility (addition of dual-fuel). Final technical report

    SciTech Connect (OSTI)

    Keel, J.S.

    1982-11-03

    This report describes the use of compressed natural gas (methane) in a dual fuel 1979 Jeep pick-up truck. Descriptions of the compressor and the dual-fuel conversion equipment are attached. (DMC)

  4. Precision tool holder with flexure-adjustable, three degrees of freedom for a four-axis lathe

    DOE Patents [OSTI]

    Bono, Matthew J.; Hibbard, Robin L.

    2008-03-04

    A precision tool holder for precisely positioning a single point cutting tool on 4-axis lathe, such that the center of the radius of the tool nose is aligned with the B-axis of the machine tool, so as to facilitate the machining of precision meso-scale components with complex three-dimensional shapes with sub-.mu.m accuracy on a four-axis lathe. The device is designed to fit on a commercial diamond turning machine and can adjust the cutting tool position in three orthogonal directions with sub-micrometer resolution. In particular, the tool holder adjusts the tool position using three flexure-based mechanisms, with two flexure mechanisms adjusting the lateral position of the tool to align the tool with the B-axis, and a third flexure mechanism adjusting the height of the tool. Preferably, the flexures are driven by manual micrometer adjusters. In this manner, this tool holder simplifies the process of setting a tool with sub-.mu.m accuracy, to substantially reduce the time required to set the tool.

  5. NASTRAN-based computer program for structural dynamic analysis of horizontal axis wind turbines

    SciTech Connect (OSTI)

    Lobitz, D.W.

    1984-01-01

    This paper describes a computer program developed for structural dynamic analysis of horizontal axis wind turbines (HAWTs). It is based on the finite element method through its reliance on NASTRAN for the development of mass, stiffness, and damping matrices of the tower and rotor, which are treated in NASTRAN as separate structures. The tower is modeled in a stationary frame and the rotor in one rotating at a constant angular velocity. The two structures are subsequently joined together (external to NASTRAN) using a time-dependent transformation consistent with the hub configuration. Aerodynamic loads are computed with an established flow model based on strip theory. Aeroelastic effects are included by incorporating the local velocity and twisting deformation of the blade in the load computation. The turbulent nature of the wind, both in space and time, is modeled by adding in stochastic wind increments. The resulting equations of motion are solved in the time domain using the implicit Newmark-Beta integrator. Preliminary comparisons with data from the Boeing/NASA MOD2 HAWT indicate that the code is capable of accurately and efficiently predicting the response of HAWTs driven by turbulent winds.

  6. LayTracks3D: A new approach for meshing general solids using medial axis transform

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Quadros, William Roshan

    2015-08-22

    This study presents an extension of the all-quad meshing algorithm called LayTracks to generate high quality hex-dominant meshes of general solids. LayTracks3D uses the mapping between the Medial Axis (MA) and the boundary of the 3D domain to decompose complex 3D domains into simpler domains called Tracks. Tracks in 3D have no branches and are symmetric, non-intersecting, orthogonal to the boundary, and the shortest path from the MA to the boundary. These properties of tracks result in desired meshes with near cube shape elements at the boundary, structured mesh along the boundary normal with any irregular nodes restricted to themore » MA, and sharp boundary feature preservation. The algorithm has been tested on a few industrial CAD models and hex-dominant meshes are shown in the Results section. Work is underway to extend LayTracks3D to generate all-hex meshes.« less

  7. Improvements in dose calculation accuracy for small off-axis targets in high dose per fraction tomotherapy

    SciTech Connect (OSTI)

    Hardcastle, Nicholas; Bayliss, Adam; Wong, Jeannie Hsiu Ding; Rosenfeld, Anatoly B.; Tome, Wolfgang A.

    2012-08-15

    Purpose: A recent field safety notice from TomoTherapy detailed the underdosing of small, off-axis targets when receiving high doses per fraction. This is due to angular undersampling in the dose calculation gantry angles. This study evaluates a correction method to reduce the underdosing, to be implemented in the current version (v4.1) of the TomoTherapy treatment planning software. Methods: The correction method, termed 'Super Sampling' involved the tripling of the number of gantry angles from which the dose is calculated during optimization and dose calculation. Radiochromic film was used to measure the dose to small targets at various off-axis distances receiving a minimum of 21 Gy in one fraction. Measurements were also performed for single small targets at the center of the Lucy phantom, using radiochromic film and the dose magnifying glass (DMG). Results: Without super sampling, the peak dose deficit increased from 0% to 18% for a 10 mm target and 0% to 30% for a 5 mm target as off-axis target distances increased from 0 to 16.5 cm. When super sampling was turned on, the dose deficit trend was removed and all peak doses were within 5% of the planned dose. For measurements in the Lucy phantom at 9.7 cm off-axis, the positional and dose magnitude accuracy using super sampling was verified using radiochromic film and the DMG. Conclusions: A correction method implemented in the TomoTherapy treatment planning system which triples the angular sampling of the gantry angles used during optimization and dose calculation removes the underdosing for targets as small as 5 mm diameter, up to 16.5 cm off-axis receiving up to 21 Gy.

  8. Dual manifold system and method for fluid transfer

    DOE Patents [OSTI]

    Doktycz, Mitchel J.; Bryan, William Louis; Kress, Reid

    2003-05-27

    A dual-manifold assembly is provided for the rapid, parallel transfer of liquid reagents from a microtiter plate to a solid state microelectronic device having biological sensors integrated thereon. The assembly includes aspiration and dispense manifolds connected by a plurality of conduits. In operation, the aspiration manifold is actuated such that the aspiration manifold is seated onto an array of reagent-filled wells of the microtiter plate. The wells are pressurized to force reagent through conduits toward the dispense manifold. A pressure pulse provided by a standard ink-jet printhead ejects nanoliter-to-picoliter droplets of reagent through an array of printhead orifices and onto test sites on the surface of the microelectronic device.

  9. Dual manifold system and method for fluid transfer

    DOE Patents [OSTI]

    Doktycz, Mitchel J.; Bryan, William Louis; Kress, Reid

    2003-09-30

    A dual-manifold assembly is provided for the rapid, parallel transfer of liquid reagents from a microtiter plate to a solid state microelectronic device having biological sensors integrated thereon. The assembly includes aspiration and dispense manifolds connected by a plurality of conduits. In operation, the aspiration manifold is actuated such that the aspiration manifold is seated onto an array of reagent-filled wells of the microtiter plate. The wells are pressurized to force reagent through conduits toward the dispense manifold. A pressure pulse provided by a standard ink-jet printhead ejects nanoliter-to-picoliter droplets of reagent through an array of printhead orifices and onto test sites on the surface of the microelectronic device.

  10. Investigation of plasma diagnostics using a dual frequency harmonic technique

    SciTech Connect (OSTI)

    Kim, Dong-Hwan; Kim, Young-Do; Cho, Sung-Won; Kim, Yu-Sin; Chung, Chin-Wook

    2014-09-07

    Plasma diagnostic methods using harmonic currents analysis of electrostatic probes were experimentally investigated to understand the differences in their measurement of the plasma parameters. When dual frequency voltage (ω{sub 1},ω{sub 2}) was applied to a probe, various harmonic currents (ω{sub 1}, 2ω{sub 1},ω{sub 2}, 2ω{sub 2},ω{sub 2}±ω{sub 1},ω{sub 2}±2ω{sub 1}) were generated due to the non-linearity of the probe sheath. The electron temperature can be obtained from the ratio of the two harmonics of the probe currents. According to the combinations of the two harmonics, the sensitivities in the measurement of the electron temperature differed, and this results in a difference of the electron temperature. From experiments and simulation, it is shown that this difference is caused by the systematic and random noise.

  11. Parameterized reduced-order models using hyper-dual numbers.

    SciTech Connect (OSTI)

    Fike, Jeffrey A.; Brake, Matthew Robert

    2013-10-01

    The goal of most computational simulations is to accurately predict the behavior of a real, physical system. Accurate predictions often require very computationally expensive analyses and so reduced order models (ROMs) are commonly used. ROMs aim to reduce the computational cost of the simulations while still providing accurate results by including all of the salient physics of the real system in the ROM. However, real, physical systems often deviate from the idealized models used in simulations due to variations in manufacturing or other factors. One approach to this issue is to create a parameterized model in order to characterize the effect of perturbations from the nominal model on the behavior of the system. This report presents a methodology for developing parameterized ROMs, which is based on Craig-Bampton component mode synthesis and the use of hyper-dual numbers to calculate the derivatives necessary for the parameterization.

  12. Dual annular rotating "windowed" nuclear reflector reactor control system

    DOE Patents [OSTI]

    Jacox, Michael G.; Drexler, Robert L.; Hunt, Robert N. M.; Lake, James A.

    1994-01-01

    A nuclear reactor control system is provided in a nuclear reactor having a core operating in the fast neutron energy spectrum where criticality control is achieved by neutron leakage. The control system includes dual annular, rotatable reflector rings. There are two reflector rings: an inner reflector ring and an outer reflector ring. The reflectors are concentrically assembled, surround the reactor core, and each reflector ring includes a plurality of openings. The openings in each ring are capable of being aligned or non-aligned with each other. Independent driving means for each of the annular reflector rings is provided so that reactor criticality can be initiated and controlled by rotation of either reflector ring such that the extent of alignment of the openings in each ring controls the reflection of neutrons from the core.

  13. Representing ductile damage with the dual domain material point method

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Long, C. C.; Zhang, D. Z.; Bronkhorst, C. A.; Gray, III, G. T.

    2015-12-14

    In this study, we incorporate a ductile damage material model into a computational framework based on the Dual Domain Material Point (DDMP) method. As an example, simulations of a flyer plate experiment involving ductile void growth and material failure are performed. The results are compared with experiments performed on high purity tantalum. We also compare the numerical results obtained from the DDMP method with those obtained from the traditional Material Point Method (MPM). Effects of an overstress model, artificial viscosity, and physical viscosity are investigated. Our results show that a physical bulk viscosity and overstress model are important in thismore » impact and failure problem, while physical shear viscosity and artificial shock viscosity have negligible effects. A simple numerical procedure with guaranteed convergence is introduced to solve for the equilibrium plastic state from the ductile damage model.« less

  14. Representing ductile damage with the dual domain material point method

    SciTech Connect (OSTI)

    Long, C. C.; Zhang, D. Z.; Bronkhorst, C. A.; Gray, III, G. T.

    2015-12-14

    In this study, we incorporate a ductile damage material model into a computational framework based on the Dual Domain Material Point (DDMP) method. As an example, simulations of a flyer plate experiment involving ductile void growth and material failure are performed. The results are compared with experiments performed on high purity tantalum. We also compare the numerical results obtained from the DDMP method with those obtained from the traditional Material Point Method (MPM). Effects of an overstress model, artificial viscosity, and physical viscosity are investigated. Our results show that a physical bulk viscosity and overstress model are important in this impact and failure problem, while physical shear viscosity and artificial shock viscosity have negligible effects. A simple numerical procedure with guaranteed convergence is introduced to solve for the equilibrium plastic state from the ductile damage model.

  15. Iterative Self-Dual Reconstruction on Radar Image Recovery

    SciTech Connect (OSTI)

    Martins, Charles; Medeiros, Fatima; Ushizima, Daniela; Bezerra, Francisco; Marques, Regis; Mascarenhas, Nelson

    2010-05-21

    Imaging systems as ultrasound, sonar, laser and synthetic aperture radar (SAR) are subjected to speckle noise during image acquisition. Before analyzing these images, it is often necessary to remove the speckle noise using filters. We combine properties of two mathematical morphology filters with speckle statistics to propose a signal-dependent noise filter to multiplicative noise. We describe a multiscale scheme that preserves sharp edges while it smooths homogeneous areas, by combining local statistics with two mathematical morphology filters: the alternating sequential and the self-dual reconstruction algorithms. The experimental results show that the proposed approach is less sensitive to varying window sizes when applied to simulated and real SAR images in comparison with standard filters.

  16. Slowly Varying Dilaton Cosmologies and Their Field Theory Duals

    SciTech Connect (OSTI)

    Awad, Adel; Das, Sumit R.; Ghosh, Archisman; Oh, Jae-Hyuk; Trivedi, Sandip P.; /Tata Inst. /Stanford U., ITP /SLAC

    2011-06-28

    We consider a deformation of the AdS{sub 5} x S{sup 5} solution of IIB supergravity obtained by taking the boundary value of the dilaton to be time dependent. The time dependence is taken to be slowly varying on the AdS scale thereby introducing a small parameter {epsilon}. The boundary dilaton has a profile which asymptotes to a constant in the far past and future and attains a minimum value at intermediate times. We construct the sugra solution to first non-trivial order in {epsilon}, and find that it is smooth, horizon free, and asymptotically AdS{sub 5} x S{sup 5} in the far future. When the intermediate values of the dilaton becomes small enough the curvature becomes of order the string scale and the sugra approximation breaks down. The resulting dynamics is analysed in the dual SU(N) gauge theory on S{sup 3} with a time dependent coupling constant which varies slowly. When N{epsilon} << 1, we find that a quantum adiabatic approximation is applicable, and use it to argue that at late times the geometry becomes smooth AdS{sub 5} x S{sup 5} again. When N{epsilon} >> 1, we formulate a classical adiabatic perturbation theory based on coherent states which arises in the large N limit. For large values of the tHooft coupling this reproduces the supergravity results. For small 'tHooft coupling the coherent state calculations become involved and we cannot reach a definite conclusion. We argue that the final state should have a dual description which is mostly smooth AdS5 space with the possible presence of a small black hole.

  17. Structural Design of a Horizontal-Axis Tidal Current Turbine Composite Blade

    SciTech Connect (OSTI)

    Bir, G. S.; Lawson, M. J.; Li, Y.

    2011-10-01

    This paper describes the structural design of a tidal composite blade. The structural design is preceded by two steps: hydrodynamic design and determination of extreme loads. The hydrodynamic design provides the chord and twist distributions along the blade length that result in optimal performance of the tidal turbine over its lifetime. The extreme loads, i.e. the extreme flap and edgewise loads that the blade would likely encounter over its lifetime, are associated with extreme tidal flow conditions and are obtained using a computational fluid dynamics (CFD) software. Given the blade external shape and the extreme loads, we use a laminate-theory-based structural design to determine the optimal layout of composite laminas such that the ultimate-strength and buckling-resistance criteria are satisfied at all points in the blade. The structural design approach allows for arbitrary specification of the chord, twist, and airfoil geometry along the blade and an arbitrary number of shear webs. In addition, certain fabrication criteria are imposed, for example, each composite laminate must be an integral multiple of its constituent ply thickness. In the present effort, the structural design uses only static extreme loads; dynamic-loads-based fatigue design will be addressed in the future. Following the blade design, we compute the distributed structural properties, i.e. flap stiffness, edgewise stiffness, torsion stiffness, mass, moments of inertia, elastic-axis offset, and center-of-mass offset along the blade. Such properties are required by hydro-elastic codes to model the tidal current turbine and to perform modal, stability, loads, and response analyses.

  18. IONIZATION SOURCE OF A MINOR-AXIS CLOUD IN THE OUTER HALO OF M82

    SciTech Connect (OSTI)

    Matsubayashi, K.; Taniguchi, Y.; Kajisawa, M.; Shioya, Y.; Sugai, H.; Shimono, A.; Hattori, T.; Ozaki, S.; Yoshikawa, T.; Nagao, T.; Bland-Hawthorn, J.

    2012-12-10

    The M82 ''cap'' is a gas cloud at a projected radius of 11.6 kpc along the minor axis of this well-known superwind source. The cap has been detected in optical line emission and X-ray emission and therefore provides an important probe of the wind energetics. In order to investigate the ionization source of the cap, we observed it with the Kyoto3DII Fabry-Perot instrument mounted on the Subaru Telescope. Deep continuum, H{alpha}, [N II]{lambda}6583/H{alpha}, and [S II]{lambda}{lambda}6716,6731/H{alpha} maps were obtained with subarcsecond resolution. The superior spatial resolution compared to earlier studies reveals a number of bright H{alpha} emitting clouds within the cap. The emission line widths ({approx}< 100 km s{sup -1} FWHM) and line ratios in the newly identified knots are most reasonably explained by slow to moderate shocks velocities (v{sub shock} 40-80 km s{sup -1}) driven by a fast wind into dense clouds. The momentum input from the M82 nuclear starburst region is enough to produce the observed shock. Consequently, earlier claims of photoionization by the central starburst are ruled out because they cannot explain the observed fluxes of the densest knots unless the UV escape fraction is very high (f{sub esc} > 60%), i.e., an order of magnitude higher than observed in dwarf galaxies to date. Using these results, we discuss the evolutionary history of the M82 superwind. Future UV/X-ray surveys are expected to confirm that the temperature of the gas is consistent with our moderate shock model.

  19. Lean NOx Reduction with Dual Layer LNT/SCR Catalysts | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Reduction with Dual Layer LNT/SCR Catalysts Lean NOx Reduction with Dual Layer LNT/SCR Catalysts Results show that a series of dual layer catalysts with a bottom layer of LNT catalyst and a top layer of SCR catalyst can carry out coupled ammonia generation and NOx reduction, achieving high NOx conversion with minimal ammonia slip deer12_harold.pdf (5.41 MB) More Documents & Publications Development of Optimal Catalyst Designs and Operating Strategies for Lean NOx Reduction in Coupled LNT-SCR

  20. Factors influencing the development and implementation of advanced radiographer practice in Australia – a qualitative study using an interpretative phenomenological approach

    SciTech Connect (OSTI)

    Page, Barbara A; Bernoth, Maree; Davidson, Rob

    2014-09-15

    The purpose of this study was to explore the factors influencing the implementation or the lack of implementation of advanced practitioner role in Australia. This study uses an interpretative phenomenological approach to explore the in-depth real life issues, which surround the advanced practitioner as a solution to radiologist workforce shortages in Australia. Research participants are radiographers, radiation therapists and health managers registered with the Australian Institute of Radiography (AIR) and holding senior professional and AIR Board positions with knowledge of current advanced practice. In total, seven interviews were conducted revealing education, governance, technical, people issues, change management, government, costs and timing as critical factors influencing advanced practice in Australia. Seven participants in this study perceived an advanced practice role might have major benefits and a positive impact on the immediate and long-term management of patients. Another finding is the greater respect and appreciation of each other's roles and expertise within the multidisciplinary healthcare team. Engagement is required of the critical stakeholders that have been identified as ‘blockers’ (radiologists, health departments) as well as identified allies (e.g. emergency clinicians, supportive radiologists, patient advocacy groups). The research supports that the AIR has a role to play for the professional identity of radiographers and shaping the advanced practice role in Australia.

  1. Near-resonant second-order nonlinear susceptibility in c-axis oriented ZnO nanorods

    SciTech Connect (OSTI)

    Liu, Weiwei; Wang, Kai; Long, Hua; Wang, Bing Lu, Peixiang; Chu, Sheng

    2014-08-18

    Near-resonant second-harmonic generation (SHG) in c-axis oriented ZnO nanorods is studied under the femtosecond laser with wavelength from 780?nm to 810?nm. A highly efficient SHG is obtained, which is attributed to the d{sub 131} component of the second-order nonlinear susceptibility. The largest d{sub 131} value is estimated to be 10.2?pm/V at the pumping wavelength of 800?nm, which indicates a large SHG response of the c-axis oriented ZnO nanorods in the near-resonant region. Theoretical calculation based on finite-difference time-domain simulation suggests a four-fold local-field enhancement of the SHG.

  2. Six-axis multi-anvil press for high-pressure, high-temperature neutron diffraction experiments

    SciTech Connect (OSTI)

    Sano-Furukawa, A. Hattori, T.; Arima, H.; Yamada, A.; Tabata, S.; Kondo, M.; Nakamura, A.; Kagi, H.; Yagi, T.

    2014-11-15

    We developed a six-axis multi-anvil press, ATSUHIME, for high-pressure and high-temperature in situ time-of-flight neutron powder diffraction experiments. The press has six orthogonally oriented hydraulic rams that operate individually to compress a cubic sample assembly. Experiments indicate that the press can generate pressures up to 9.3 GPa and temperatures up to 2000 K using a 6-6-type cell assembly, with available sample volume of about 50 mm{sup 3}. Using a 6-8-type cell assembly, the available conditions expand to 16 GPa and 1273 K. Because the six-axis press has no guide blocks, there is sufficient space around the sample to use the aperture for diffraction and place an incident slit, radial collimators, and a neutron imaging camera close to the sample. Combination of the six-axis press and the collimation devices realized high-quality diffraction pattern with no contamination from the heater or the sample container surrounding the sample. This press constitutes a new tool for using neutron diffraction to study the structures of crystals and liquids under high pressures and temperatures.

  3. Improved proton computed tomography by dual modality image reconstruction

    SciTech Connect (OSTI)

    Hansen, David C. Bassler, Niels; Petersen, Jørgen Breede Baltzer; Sørensen, Thomas Sangild

    2014-03-15

    Purpose: Proton computed tomography (CT) is a promising image modality for improving the stopping power estimates and dose calculations for particle therapy. However, the finite range of about 33 cm of water of most commercial proton therapy systems limits the sites that can be scanned from a full 360° rotation. In this paper the authors propose a method to overcome the problem using a dual modality reconstruction (DMR) combining the proton data with a cone-beam x-ray prior. Methods: A Catphan 600 phantom was scanned using a cone beam x-ray CT scanner. A digital replica of the phantom was created in the Monte Carlo code Geant4 and a 360° proton CT scan was simulated, storing the entrance and exit position and momentum vector of every proton. Proton CT images were reconstructed using a varying number of angles from the scan. The proton CT images were reconstructed using a constrained nonlinear conjugate gradient algorithm, minimizing total variation and the x-ray CT prior while remaining consistent with the proton projection data. The proton histories were reconstructed along curved cubic-spline paths. Results: The spatial resolution of the cone beam CT prior was retained for the fully sampled case and the 90° interval case, with the MTF = 0.5 (modulation transfer function) ranging from 5.22 to 5.65 linepairs/cm. In the 45° interval case, the MTF = 0.5 dropped to 3.91 linepairs/cm For the fully sampled DMR, the maximal root mean square (RMS) error was 0.006 in units of relative stopping power. For the limited angle cases the maximal RMS error was 0.18, an almost five-fold improvement over the cone beam CT estimate. Conclusions: Dual modality reconstruction yields the high spatial resolution of cone beam x-ray CT while maintaining the improved stopping power estimation of proton CT. In the case of limited angles, the use of prior image proton CT greatly improves the resolution and stopping power estimate, but does not fully achieve the quality of a 360

  4. A Manufacturing Cost Analysis Relevant to Single- and Dual-Junction...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    A Manufacturing Cost Analysis Relevant to Single- and Dual-Junction Photovoltaic Cells Fabricated with III-Vs and III-Vs Grown on Silicon A Manufacturing Cost Analysis Relevant to ...

  5. A Nonproliferation Third Party for Dual-use Industries - Legal Issues for Consideration

    SciTech Connect (OSTI)

    Morris, Frederic A.; Seward, Amy M.; Kurzrok, Andrew J.

    2012-10-01

    This paper discusses legal issues in connection with formation of a “third party” to facilitate information sharing and best practices by companies in nuclear-related dual-use industries.

  6. Source book for planning nuclear dual-purpose electric/distillation desalination plants

    SciTech Connect (OSTI)

    Reed, S.A.

    1981-02-01

    A source book on nuclear dual-purpose electric/distillation desalination plants was prepared to assist government and other planners in preparing broad evaluations of proposed applications of dual-purpose plants. The document is divided into five major sections. Section 1 presents general discussions relating to the benefits of dual-purpose plants, and spectrum for water-to-power ratios. Section 2 presents information on commercial nuclear plants manufactured by US manufacturers. Section 3 gives information on distillation desalting processes and equipment. Section 4 presents a discussion on feedwater pretreatment and scale control. Section 5 deals with methods for coupling the distillation and electrical generating plants to operate in the dual mode.

  7. Dual modulation laser line-locking technique for wavelength modulation spectroscopy

    DOE Patents [OSTI]

    Bomse, David S.; Hovde, D. Christian; Silver, Joel A.

    2002-01-01

    Disclosed are a method and apparatus for dual modulation of an optical spectroscopy laser. Demodulation is accomplished in a manner resulting in measurement of absorbance of a gas species, as well as stabilization of laser wavelength and baseline noise reduction.

  8. Toward the AdS/CFT gravity dual for high energy collisions. II...

    Office of Scientific and Technical Information (OSTI)

    II. The stress tensor on the boundary Citation Details In-Document Search Title: Toward the AdSCFT gravity dual for high energy collisions. II. The stress tensor on the boundary ...

  9. On-chip dual-comb based on quantum cascade laser frequency combs

    SciTech Connect (OSTI)

    Villares, G. Wolf, J.; Kazakov, D.; Süess, M. J.; Beck, M.; Faist, J.; Hugi, A.

    2015-12-21

    Dual-comb spectroscopy is emerging as an appealing application of mid-infrared frequency combs for high-resolution molecular spectroscopy, as it leverages on the unique coherence properties of frequency combs. Here, we present an on-chip dual-comb source based on mid-infrared quantum cascade laser frequency combs. Control of the combs repetition and offset frequencies is obtained by integrating micro-heaters next to each laser. We show that a full control of the dual-comb system is possible, by measuring a multi-heterodyne beating corresponding to an optical bandwidth of 32 cm{sup −1} centered at 1330 cm{sup −1} (7.52 μm), demonstrating that this device represents a critical step towards compact dual-comb systems.

  10. A Universal Dual-Fuel Controller for OEM/Aftermarket Diesel Engineswit...

    Broader source: Energy.gov (indexed) [DOE]

    KB) More Documents & Publications Active DPF for Off-Road Particulate Matter (PM) Control Propane-Diesel Dual Fuel for CO2 and Nox Reduction DPF for a Tractor Auxiliary Power Unit

  11. Summary of Investigations on Technical Feasibility of Direct Disposal of Dual-Purpose Canisters R1

    Office of Energy Efficiency and Renewable Energy (EERE)

    This study has evaluated the technical feasibility of direct disposal in a geologic repository, of commercial spent nuclear fuel (SNF) in dual-purpose canisters (DPCs) of existing designs.  The...

  12. Preliminary Report on Dual-Purpose Canister Disposal Alternatives (FY13)

    Office of Energy Efficiency and Renewable Energy (EERE)

    This report documents the first phase of a multi-year project to understand the technical feasibility and logistical implications of direct disposal of spent nuclear fuel in existing dual-purpose canisters (DPCs) and other types of storage casks.

  13. Diagnostic quality of mammograms obtained with a new low-radiation-dose dual-screen and dual-emulsion film combination

    SciTech Connect (OSTI)

    Wojtasek, D.A.; Teixidor, H.S.; Govoni, A.F.; Gareen, I.F. )

    1990-02-01

    We evaluated the image quality of mammograms made by using a new dual-screen, dual-emulsion film combination (Kodak Min-R Fast screen, T-Mat Mll film) that permits reduction of radiation exposure by approximately 50% when compared with a standard single-screen, single-emulsion film system (Kodak Min-R screen, OM-1 film). This new film has been improved when compared with earlier T-Mat M film, including the introduction of an inert dye to reduce light crossover to essentially 0%. Mammogram pairs made with the dual-emulsion film combination and the standard single-emulsion film combination were obtained in 50 patients otherwise undergoing routine mammography. The image pairs were randomized and evaluated by three radiologists who used a three-point scale (better, same, or worse). Each pair was evaluated with regard to parenchymal contrast, sharpness, and latitude, as well as the number and sharpness of calcifications (n = 19) and sharpness of masses (n = 12) when present. All three observers found the dual-emulsion film combination to be better than or the same as the standard with regard to parenchymal sharpness (94-100%), the number and sharpness of calcifications (98-100%), and sharpness of masses (100%). Two observers found the dual-emulsion film combination to be significantly worse (p less than .05) than the standard with respect to parenchymal contrast (72%, 86%), and all three observers rated it significantly worse for film latitude (14 to 42%). Our results suggest that this new dual-emulsion film combination that allows mammography to be performed with less radiation exposure can be used without loss of image quality.

  14. Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Operation with Low Degradation | Department of Energy for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Advanced Materials for Reversible Solid Oxide Fuel Cell (RSOFC), Dual Mode Operation with Low Degradation Presented at the Department of Energy Fuel Cell Projects Kickoff Meeting, September 1 - October 1, 2009 petri_versa%20_power_kickoff.pdf (3.53 MB) More Documents & Publications Reversible Fuel Cells Workshop Summary Report Progress on the

  15. Project Profile: Sensible Heat, Direct, Dual-Media Thermal Energy Storage

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Module | Department of Energy Sensible Heat, Direct, Dual-Media Thermal Energy Storage Module Project Profile: Sensible Heat, Direct, Dual-Media Thermal Energy Storage Module Acciona logo Acciona Solar, under the Thermal Storage FOA, plans to develop a prototype thermal energy storage (TES) module with high efficiency. This project is looking at a packed or structured bed TES tank with molten salt flowing through it. Approach A computational modeling of molten salt heat transfer fluid

  16. Commissioning of a proton gantry equipped with dual x-ray imagers and a robotic patient positioner, and evaluation of the accuracy of single-beam image registration for this system

    SciTech Connect (OSTI)

    Wang, Ning; Ghebremedhin, Abiel; Patyal, Baldev

    2015-06-15

    Purpose: To check the accuracy of a gantry equipped with dual x-ray imagers and a robotic patient positioner for proton radiotherapy, and to evaluate the accuracy and feasibility of single-beam registration using the robotic positioner. Methods: One of the proton treatment rooms at their institution was upgraded to include a robotic patient positioner (couch) with 6 degrees of freedom and dual orthogonal kilovoltage x-ray imaging panels. The wander of the proton beam central axis, the wander of the beamline, and the orthogonal image panel crosswires from the gantry isocenter were measured for different gantry angles. The couch movement accuracy and couch wander from the gantry isocenter were measured for couch loadings of 50–300 lb with couch rotations from 0° to ±90°. The combined accuracy of the gantry, couch, and imagers was checked using a custom-made 30 × 30 × 30 cm{sup 3} Styrofoam phantom with beekleys embedded in it. A treatment in this room can be set up and registered at a setup field location, then moved precisely to any other treatment location without requiring additional image registration. The accuracy of the single-beam registration strategy was checked for treatments containing multiple beams with different combinations of gantry angles, couch yaws, and beam locations. Results: The proton beam central axis wander from the gantry isocenter was within 0.5 mm with gantry rotations in both clockwise (CW) and counterclockwise (CCW) directions. The maximum wander of the beamline and orthogonal imager crosswire centers from the gantry isocenter were within 0.5 and 0.8 mm, respectively, with the gantry rotations in CW and CCW directions. Vertical and horizontal couch wanders from the gantry isocenter were within 0.4 and 1.3 mm, respectively, for couch yaw from 0° to ±90°. For a treatment with multiple beams with different gantry angles, couch yaws, and beam locations, the measured displacements of treatment beam locations from the one based on

  17. Producing thin film photovoltaic modules with high integrity interconnects and dual layer contacts

    DOE Patents [OSTI]

    Jansen, Kai W.; Maley, Nagi

    2001-01-01

    High performance photovoltaic modules are produced with improved interconnects by a special process. Advantageously, the photovoltaic modules have a dual layer back (rear) contact and a front contact with at least one layer. The front contact and the inner layer of the back contact can comprise a transparent conductive oxide. The outer layer of the back contact can comprise a metal or metal oxide. The front contact can also have a dielectric layer. In one form, the dual layer back contact comprises a zinc oxide inner layer and an aluminum outer layer and the front contact comprises a tin oxide inner layer and a silicon dioxide dielectric outer layer. One or more amorphous silicon-containing thin film semiconductors can be deposited between the front and back contacts. The contacts can be positioned between a substrate and an optional superstrate. During production, the transparent conductive oxide layer of the front contact is scribed by a laser, then the amorphous silicon-containing semiconductors and inner layer of the dual layer back contact are simultaneously scribed and trenched (drilled) by the laser and the trench is subsequently filled with the same metal as the outer layer of the dual layer back contact to provide a superb mechanical and electrical interconnect between the front contact and the outer layer of the dual layer back contact. The outer layer of the dual layer back contact can then be scribed by the laser. For enhanced environmental protection, the photovoltaic modules can be encapsulated.

  18. Producing thin film photovoltaic modules with high integrity interconnects and dual layer contacts

    DOE Patents [OSTI]

    Jansen, Kai W.; Maley, Nagi

    2000-01-01

    High performance photovoltaic modules are produced with improved interconnects by a special process. Advantageously, the photovoltaic modules have a dual layer back (rear) contact and a front contact with at least one layer. The front contact and the inner layer of the back contact can comprise a transparent conductive oxide. The outer layer of the back contact can comprise a metal or metal oxide. The front contact can also have a dielectric layer. In one form, the dual layer back contact comprises a zinc oxide inner layer and an aluminum outer layer and the front contact comprises a tin oxide inner layer and a silicon dioxide dielectric outer layer. One or more amorphous silicon-containing thin film semiconductors can be deposited between the front and back contacts. The contacts can be positioned between a substrate and an optional superstrate. During production, the transparent conductive oxide layer of the front contact is scribed by a laser, then the amorphous silicon-containing semiconductors and inner layer of the dual layer back contact are simultaneously scribed and trenched (drilled) by the laser and the trench is subsequently filled with the same metal as the outer layer of the dual layer back contact to provide a superb mechanical and electrical interconnect between the front contact and the outer layer of the dual layer back contact. The outer layer of the dual layer back contact can then be scribed by the laser. For enhanced environmental protection, the photovoltaic modules can be encapsulated.

  19. Dual curvature acoustically damped concentrating collector. Final technical report

    SciTech Connect (OSTI)

    Smith, G.A.; Rausch, R.A.

    1980-05-01

    A development program was conducted to investigate the design and performance parameters of a novel, dual curvature, concentrating solar collector. The reflector of the solar collector is achieved with a stretched-film reflective surface that approximates a hyperbolic paraboloid and is capable of line-focusing at concentration ratios ranging from 10 to 20X. A prototype collector was designed based on analytical and experimental component trade-off activities as well as economic analyses of solar thermal heating and cooling systems incorporating this type of collector. A prototype collector incorporating six 0.66 x 1.22 m (2 x 4 ft) was fabricated and subjected to a limited thermal efficiency test program. A peak efficiency of 36% at 121/sup 0/C (250/sup 0/F) was achieved based upon the gross aperture area. Commercialization activities were conducted, including estimated production costs of $134.44/m/sup 2/ ($12.49/ft/sup 2/) for the collector assembly (including a local suntracker and controls) and $24.33/m/sup 2/ ($2.26/ft/sup 2/) for the reflector subassembly.

  20. Dual variational principles for nonlinear traveling waves in multifluid plasmas

    SciTech Connect (OSTI)

    Webb, G. M.; McKenzie, J. F.; Mace, R. L.; Ko, C. M.; Zank, G. P.

    2007-08-15

    A Hamiltonian description of nonlinear, obliquely propagating traveling waves in a charge neutral, electron-proton, multifluid plasma is developed. The governing equations are written as a dual spatial Hamiltonian system. In the first formulation, the Hamiltonian is identified with the longitudinal, x-momentum flux integral P{sub x}=const, in which the energy integral {epsilon}={epsilon}{sub 0} acts as a constraint, and the Hamiltonian evolution operator is d/dx, where x is the position coordinate in the wave frame. In the second Hamiltonian formulation, the Hamiltonian is proportional to the conserved energy integral {epsilon}, in which the momentum integral P{sub x}=const acts as a constraint, and the Hamiltonian evolution operator d/d{tau}=u{sub x}d/dx is the Lagrangian time derivative where u{sub x} is the x component of the electron and proton fluids. The analysis is facilitated by using the de Hoffman-Teller frame of magnetohydrodynamic shock theory to simplify the transverse electron and proton momentum equations. The system is exactly integrable in cases in which the total transverse momentum fluxes of the system are zero in the de Hoffman-Teller frame. The implications of this constraint for the Alfven Mach number of the traveling wave are discussed. The physical conditions for the formation of whistler oscillitons based on the whistler dispersion equation are discussed.

  1. Indirect-fired gas turbine dual fuel cell power cycle

    DOE Patents [OSTI]

    Micheli, Paul L.; Williams, Mark C.; Sudhoff, Frederick A.

    1996-01-01

    A fuel cell and gas turbine combined cycle system which includes dual fuel cell cycles combined with a gas turbine cycle wherein a solid oxide fuel cell cycle operated at a pressure of between 6 to 15 atms tops the turbine cycle and is used to produce CO.sub.2 for a molten carbonate fuel cell cycle which bottoms the turbine and is operated at essentially atmospheric pressure. A high pressure combustor is used to combust the excess fuel from the topping fuel cell cycle to further heat the pressurized gas driving the turbine. A low pressure combustor is used to combust the excess fuel from the bottoming fuel cell to reheat the gas stream passing out of the turbine which is used to preheat the pressurized air stream entering the topping fuel cell before passing into the bottoming fuel cell cathode. The CO.sub.2 generated in the solid oxide fuel cell cycle cascades through the system to the molten carbonate fuel cell cycle cathode.

  2. DUAL HALOS AND FORMATION OF EARLY-TYPE GALAXIES

    SciTech Connect (OSTI)

    Park, Hong Soo; Lee, Myung Gyoon E-mail: mglee@astro.snu.ac.kr

    2013-08-20

    We present a determination of the two-dimensional shape parameters of the blue and red globular cluster systems (GCSs) in a large number of elliptical galaxies and lenticular galaxies (early-type galaxies, called ETGs). We use a homogeneous data set of the globular clusters in 23 ETGs obtained from the HST/ACS Virgo Cluster Survey. The position angles of both blue and red GCSs show a correlation with those of the stellar light distribution, showing that the major axes of the GCSs are well aligned with those of their host galaxies. However, the shapes of the red GCSs show a tight correlation with the stellar light distribution as well as with the rotation property of their host galaxies, while the shapes of the blue GCSs do much less. These provide clear geometric evidence that the origins of the blue and red globular clusters are distinct and that ETGs may have dual halos: a blue (metal-poor) halo and a red (metal-rich) halo. These two halos show significant differences in metallicity, structure, and kinematics, indicating that they are formed in two distinguishable ways. The red halos might have formed via dissipational processes with rotation, while the blue halos are through accretion.

  3. Dual-etalon, cavity-ring-down, frequency comb spectroscopy.

    SciTech Connect (OSTI)

    Strecker, Kevin E.; Chandler, David W.

    2010-10-01

    The 'dual etalon frequency comb spectrometer' is a novel low cost spectometer with limited moving parts. A broad band light source (pulsed laser, LED, lamp ...) is split into two beam paths. One travels through an etalon and a sample gas, while the second arm is just an etalon cavity, and the two beams are recombined onto a single detector. If the free spectral ranges (FSR) of the two cavities are not identical, the intensity pattern at the detector with consist of a series of heterodyne frequencies. Each mode out of the sample arm etalon with have a unique frequency in RF (radio-frequency) range, where modern electronics can easily record the signals. By monitoring these RF beat frequencies we can then determine when an optical frequencies is absorbed. The resolution is set by the FSR of the cavity, typically 10 MHz, with a bandwidth up to 100s of cm{sup -1}. In this report, the new spectrometer is described in detail and demonstration experiments on Iodine absorption are carried out. Further we discuss powerful potential next generation steps to developing this into a point sensor for monitoring combustion by-products, environmental pollutants, and warfare agents.

  4. Dual energy scanning beam laminographic x-radiography

    DOE Patents [OSTI]

    Majewski, S.; Wojcik, R.F.

    1998-04-21

    A multiple x-ray energy level imaging system includes a scanning x-ray beam and two detector design having a first low x-ray energy sensitive detector and a second high x-ray energy sensitive detector. The low x-ray energy detector is placed next to or in front of the high x-ray energy detector. The low energy sensitive detector has small stopping power for x-rays. The lower energy x-rays are absorbed and converted into electrical signals while the majority of the higher energy x-rays pass through undetected. The high energy sensitive detector has a large stopping power for x-rays as well as it having a filter placed between it and the object to absorb the lower energy x-rays. In a second embodiment; a single energy sensitive detector is provided which provides an output signal proportional to the amount of energy in each individual x-ray it absorbed. It can then have an electronic threshold or thresholds set to select two or more energy ranges for the images. By having multiple detectors located at different positions, a dual energy laminography system is possible. 6 figs.

  5. Dual energy scanning beam laminographic x-radiography

    DOE Patents [OSTI]

    Majewski, Stanislaw; Wojcik, Randolph F.

    1998-01-01

    A multiple x-ray energy level imaging system includes a scanning x-ray beam and two detector design having a first low x-ray energy sensitive detector and a second high x-ray energy sensitive detector. The low x-ray energy detector is placed next to or in front of the high x-ray energy detector. The low energy sensitive detector has small stopping power for x-rays. The lower energy x-rays are absorbed and converted into electrical signals while the majority of the higher energy x-rays pass through undetected. The high energy sensitive detector has a large stopping power for x-rays as well as it having a filter placed between it and the object to absorb the lower energy x-rays. In a second embodiment; a single energy sensitive detector is provided which provides an output signal proportional to the amount of energy in each individual x-ray it absorbed. It can then have an electronic threshold or thresholds set to select two or more energy ranges for the images. By having multiple detectors located at different positions, a dual energy laminography system is possible.

  6. Method and device for determining the position of a cutting tool relative to the rotational axis of a spindle-mounted workpiece

    DOE Patents [OSTI]

    Williams, R.R.

    1980-09-03

    The present invention is directed to a method and device for determining the location of a cutting tool with respect to the rotational axis of a spindle-mounted workpiece. A vacuum cup supporting a machinable sacrificial pin is secured to the workpiece at a location where the pin will project along and encompass the rotational axis of the workpiece. The pin is then machined into a cylinder. The position of the surface of the cutting tool contacting the machine cylinder is spaced from the rotational axis of the workpiece a distance equal to the radius of the cylinder.

  7. Enhancing the quality of radiographic images acquired with point-like gamma-ray sources through correction of the beam divergence and attenuation

    SciTech Connect (OSTI)

    Silvani, M. I.; Almeida, G. L.; Lopes, R. T.

    2014-11-11

    Radiographic images acquired with point-like gamma-ray sources exhibit a desirable low penumbra effects specially when positioned far away from the set object-detector. Such an arrangement frequently is not affordable due to the limited flux provided by a distant source. A closer source, however, has two main drawbacks, namely the degradation of the spatial resolution - as actual sources are only approximately punctual - and the non-homogeneity of the beam hitting the detector, which creates a false attenuation map of the object being inspected. This non-homogeneity is caused by the beam divergence itself and by the different thicknesses traversed the beam even if the object were an homogeneous flat plate. In this work, radiographic images of objects with different geometries, such as flat plates and pipes have undergone a correction of beam divergence and attenuation addressing the experimental verification of the capability and soundness of an algorithm formerly developed to generate and process synthetic images. The impact of other parameters, including source-detector gap, attenuation coefficient, ratio defective-to-main hull thickness and counting statistics have been assessed for specifically tailored test-objects aiming at the evaluation of the ability of the proposed method to deal with different boundary conditions. All experiments have been carried out with an X-ray sensitive Imaging Plate and reactor-produced {sup 198}Au and {sup 165}Dy sources. The results have been compared with other technique showing a better capability to correct the attenuation map of inspected objects unveiling their inner structure otherwise concealed by the poor contrast caused by the beam divergence and attenuation, in particular for those regions far apart from the vertical of the source.

  8. Dual energy CT for attenuation correction with PET/CT

    SciTech Connect (OSTI)

    Xia, Ting; Alessio, Adam M.; Kinahan, Paul E.

    2014-01-15

    Purpose: The authors evaluate the energy dependent noise and bias properties of monoenergetic images synthesized from dual-energy CT (DECT) acquisitions. These monoenergetic images can be used to estimate attenuation coefficients at energies suitable for positron emission tomography (PET) and single-photon emission computed tomography (SPECT) imaging. This is becoming more relevant with the increased use of quantitative imaging by PET/CT and SPECT/CT scanners. There are, however, potential variations in the noise and bias of synthesized monoenergetic images as a function of energy. Methods: The authors used analytic approximations and simulations to estimate the noise and bias of synthesized monoenergetic images of water-filled cylinders with different shapes and the NURBS-based cardiac-torso (NCAT) phantom from 40 to 520 keV, the range of SPECT and PET energies. The dual-kVp spectra were based on the GE Lightspeed VCT scanner at 80 and 140 kVp with added filtration of 0.5 mm Cu. The authors evaluated strategies of noise suppression with sinogram smoothing and dose minimization with reduction of tube currents at the two kVp settings. The authors compared the impact of DECT-based attenuation correction with single-kVp CT-based attenuation correction on PET quantitation for the NCAT phantom for soft tissue and high-Z materials of bone and iodine contrast enhancement. Results: Both analytic calculations and simulations displayed the expected minimum noise value for a synthesized monoenergetic image at an energy between the mean energies of the two spectra. In addition the authors found that the normalized coefficient of variation in the synthesized attenuation map increased with energy but reached a plateau near 160 keV, and then remained constant with increasing energy up to 511 keV and beyond. The bias was minimal, as the linear attenuation coefficients of the synthesized monoenergetic images were within 2.4% of the known true values across the entire energy range

  9. Dual energy CT for attenuation correction with PET/CT

    SciTech Connect (OSTI)

    Xia, Ting; Alessio, Adam M.; Kinahan, Paul E.

    2014-01-15

    Purpose: The authors evaluate the energy dependent noise and bias properties of monoenergetic images synthesized from dual-energy CT (DECT) acquisitions. These monoenergetic images can be used to estimate attenuation coefficients at energies suitable for positron emission tomography (PET) and single-photon emission computed tomography (SPECT) imaging. This is becoming more relevant with the increased use of quantitative imaging by PET/CT and SPECT/CT scanners. There are, however, potential variations in the noise and bias of synthesized monoenergetic images as a function of energy. Methods: The authors used analytic approximations and simulations to estimate the noise and bias of synthesized monoenergetic images of water-filled cylinders with different shapes and the NURBS-based cardiac-torso (NCAT) phantom from 40 to 520 keV, the range of SPECT and PET energies. The dual-kVp spectra were based on the GE Lightspeed VCT scanner at 80 and 140 kVp with added filtration of 0.5 mm Cu. The authors evaluated strategies of noise suppression with sinogram smoothing and dose minimization with reduction of tube currents at the two kVp settings. The authors compared the impact of DECT-based attenuation correction with single-kVp CT-based attenuation correction on PET quantitation for the NCAT phantom for soft tissue and high-Z materials of bone and iodine contrast enhancement. Results: Both analytic calculations and simulations displayed the expected minimum noise value for a synthesized monoenergetic image at an energy between the mean energies of the two spectra. In addition the authors found that the normalized coefficient of variation in the synthesized attenuation map increased with energy but reached a plateau near 160 keV, and then remained constant with increasing energy up to 511 keV and beyond. The bias was minimal, as the linear attenuation coefficients of the synthesized monoenergetic images were within 2.4% of the known true values across the entire energy range

  10. THE CASE FOR THE DUAL HALO OF THE MILKY WAY

    SciTech Connect (OSTI)

    Beers, Timothy C.; Lee, Young Sun; Carollo, Daniela; Norris, John E.; Freeman, Ken C. E-mail: lee@pa.msu.edu E-mail: jen@mso.anu.edu.au; and others

    2012-02-10

    Carollo et al. have recently resolved the stellar population of the Milky Way halo into at least two distinct components, an inner halo and an outer halo. This result has been criticized by Schoenrich et al., who claim that the retrograde signature associated with the outer halo is due to the adoption of faulty distances. We refute this claim, and demonstrate that the Schoenrich et al. photometric distances are themselves flawed because they adopted an incorrect main-sequence absolute magnitude relationship from the work of Ivezic et al. When compared to the recommended relation from Ivezic et al., which is tied to a Milky Way globular cluster distance scale and accounts for age and metallicity effects, the relation adopted by Schoenrich et al. yields up to 18% shorter distances for stars near the main-sequence turnoff (TO). Use of the correct relationship yields agreement between the distances assigned by Carollo et al. and Ivezic et al. for low-metallicity dwarfs to within 6%-10%. Schoenrich et al. also point out that intermediate-gravity stars (3.5 {<=}log g < 4.0) with colors redder than the TO region are likely misclassified, with which we concur. We implement a new procedure to reassign luminosity classifications for the TO stars that require it. New derivations of the rotational behavior demonstrate that the retrograde signature and high velocity dispersion of the outer-halo population remain. We summarize additional lines of evidence for a dual halo, including a test of the retrograde signature based on proper motions alone, and conclude that the preponderance of evidence strongly rejects the single-halo interpretation.

  11. Dual shell pressure balanced reactor vessel. Final project report

    SciTech Connect (OSTI)

    Robertus, R.J.; Fassbender, A.G.

    1994-10-01

    The Department of Energy`s Office of Energy Research (OER) has previously provided support for the development of several chemical processes, including supercritical water oxidation, liquefaction, and aqueous hazardous waste destruction, where chemical and phase transformations are conducted at high pressure and temperature. These and many other commercial processes require a pressure vessel capable of operating in a corrosive environment where safety and economy are important requirements. Pacific Northwest Laboratory (PNL) engineers have recently developed and patented (U.S. patent 5,167,930 December 1, 1992) a concept for a novel Dual Shell Pressure Balanced Vessel (DSPBV) which could solve a number of these problems. The technology could be immediately useful in continuing commercialization of an R&D 100 award-winning technology, Sludge-to-oil Reactor System (STORS), originally developed through funding by OER. Innotek Corporation is a small business that would be one logical end-user of the DSPBV reactor technology. Innotek is working with several major U.S. engineering firms to evaluate the potential of this technology in the disposal of wastes from sewage treatment plants. PNL entered into a CRADA with Innotek to build a bench-scale demonstration reactor and test the system to advance the economic feasibility of a variety of high pressure chemical processes. Hydrothermal processing of corrosive substances on a large scale can now be made significantly safer and more economical through use of the DSPBV. Hydrothermal chemical reactions such as wet-air oxidation and supercritical water oxidation occur in a highly corrosive environment inside a pressure vessel. Average corrosion rates from 23 to 80 miles per year have been reported by Rice (1994) and Latanision (1993).

  12. Development of more efficient impellers for horizontal axis windmills. Final report, October 1, 1980-April 30, 1982

    SciTech Connect (OSTI)

    Fosdick, G.A. Jr.

    1982-01-01

    The purpose of the project reported has been the development of a wind turbine incorporating a new concept in horizontal-axis impellers. The impeller consists of six rows of radial blades arranged to extend in a spiral covering 55/sup 0/ of arc about a hollow support section. Each blade in the rows is contoured to receive both direct flow pressure as well as airfoil lift in order to provide maximum energy transfers from low velocity airflows such as those normally found in most localities throughout the country most of the time. A disclosure of the wind turbine configuration is attached. (LEW)

  13. Preliminary analysis of the audible noise of constant-speed, horizontal-axis wind-turbine generators

    SciTech Connect (OSTI)

    Keast, D. N.; Potter, R. C.

    1980-07-01

    An analytical procedure has been developed for calculating certain aerodynamic sound levels produced by large, horizontal-axis wind-turbine generators (WTG's) such as the DOE/NASA Mods-0, -0A, -1, and -2. This preliminary procedure is based upon very limited field data from the Mod-0. It postulates a noise component due to the (constant) rotation of the blades of the WTG, plus a wake-noise component that increases with the square of the power produced by the WTG. Mechanical sound from machinery, and low-frequency impulsive sounds produced by blade interaction with the wake of the support tower are not considered.

  14. Use of off-axis injection as an alternative to geometrically merging beams in an energy-recovering linac

    DOE Patents [OSTI]

    Douglas, David R.

    2012-01-10

    A method of using off-axis particle beam injection in energy-recovering linear accelerators that increases operational efficiency while eliminating the need to merge the high energy re-circulating beam with an injected low energy beam. In this arrangement, the high energy re-circulating beam and the low energy beam are manipulated such that they are within a predetermined distance from one another and then the two immerged beams are injected into the linac and propagated through the system. The configuration permits injection without geometric beam merging as well as decelerated beam extraction without the use of typical beamline elements.

  15. Magnetic domain structure in nanocrystalline Ni-Zn-Co spinel ferrite thin films using off-axis electron holography

    SciTech Connect (OSTI)

    Zhang, D.; Ray, N. M.; Petuskey, W. T.; Smith, D. J.; McCartney, M. R.

    2014-08-28

    We report a study of the magnetic domain structure of nanocrystalline thin films of nickel-zinc ferrite. The ferrite films were synthesized using aqueous spin-spray coating at low temperature (?90?C) and showed high complex permeability in the GHz range. Electron microscopy and microanalysis revealed that the films consisted of columnar grains with uniform chemical composition. Off-axis electron holography combined with magnetic force microscopy indicated a multi-grain domain structure with in-plane magnetization. The correlation between the magnetic domain morphology and crystal structure is briefly discussed.

  16. DUAL SUPERMASSIVE BLACK HOLE CANDIDATES IN THE AGN AND GALAXY EVOLUTION SURVEY

    SciTech Connect (OSTI)

    Comerford, Julia M.; Schluns, Kyle; Greene, Jenny E.; Cool, Richard J.

    2013-11-01

    Dual supermassive black holes (SMBHs) with kiloparsec-scale separations in merger-remnant galaxies are informative tracers of galaxy evolution, but the avenue for identifying them in large numbers for such studies is not yet clear. One promising approach is to target spectroscopic signatures of systems where both SMBHs are fueled as dual active galactic nuclei (AGNs), or where one SMBH is fueled as an offset AGN. Dual AGNs may produce double-peaked narrow AGN emission lines, while offset AGNs may produce single-peaked narrow AGN emission lines with line-of-sight velocity offsets relative to the host galaxy. We search for such dual and offset systems among 173 Type 2 AGNs at z < 0.37 in the AGN and Galaxy Evolution Survey (AGES), and we find two double-peaked AGNs and five offset AGN candidates. When we compare these results to a similar search of the DEEP2 Galaxy Redshift Survey and match the two samples in color, absolute magnitude, and minimum velocity offset, we find that the fraction of AGNs that are dual SMBH candidates increases from z = 0.25 to z = 0.7 by a factor of ?6 (from 2/70 to 16/91, or 2.9{sup +3.6}{sub -1.9}% to 18{sup +5}{sub -5}%). This may be associated with the rise in the galaxy merger fraction over the same cosmic time. As further evidence for a link with galaxy mergers, the AGES offset and dual AGN candidates are tentatively ?3 times more likely than the overall AGN population to reside in a host galaxy that has a companion galaxy (from 16/173 to 2/7, or 9{sup +3}{sub -2}% to 29{sub -19}{sup +26}%). Follow-up observations of the seven offset and dual AGN candidates in AGES will definitively distinguish velocity offsets produced by dual SMBHs from those produced by narrow-line region kinematics, and will help sharpen our observational approach to detecting dual SMBHs.

  17. Inspection report: the Department of Energy's export licensing process for dual-use and munitions commodities

    SciTech Connect (OSTI)

    Friedman, Gregory H.

    1999-05-01

    Export of commodities, encouraged by both the private sector and the Federal Government, helps to improve our position in the global economy and is in the national interest of the US. However, exports of commodities or technologies, without regard to whether they may significantly contribute to the military potential of individual countries or combination of countries or enhance the proliferation of weapons of mass destruction, may adversely affect the national security of the US. The Federal Government, therefore, implements several laws, Executive Orders, and regulations to control the export of certain commodities and technologies. These commodities and technologies require a license for export. Some of the controlled items are designated as ''dual-use,'' that is, commodities and technologies that have both civilian and military application. Some dual-use commodities are designated as ''nuclear dual-use''--items controlled for nuclear nonproliferation purposes. Another group of controlled commodities is designated as munitions, which are goods and technologies that have solely military uses. The Department of Energy (Energy) conducts reviews of export license applications for nuclear dual-use items and certain munitions. On August 26, 1998, the Chairman of the Senate Committee on Governmental Affairs requested that the Inspectors General from the Departments of Commerce, Defense, Energy, State, and Treasury, and the Central Intelligence Agency (CIA), update and expand on a 1993 interagency review conducted by the Inspectors General of the Departments of Commerce, Defense, Energy, and State of the export licensing processes for dual-use and munitions commodities.

  18. DETECTION OF SEMIMAJOR AXIS DRIFTS IN 54 NEAR-EARTH ASTEROIDS: NEW MEASUREMENTS OF THE YARKOVSKY EFFECT

    SciTech Connect (OSTI)

    Nugent, C. R.; Margot, J. L.; Chesley, S. R.; Vokrouhlicky, D.

    2012-08-15

    We have identified and quantified semimajor axis drifts in near-Earth asteroids (NEAs) by performing orbital fits to optical and radar astrometry of all numbered NEAs. We focus on a subset of 54 NEAs that exhibit some of the most reliable and strongest drift rates. Our selection criteria include a Yarkovsky sensitivity metric that quantifies the detectability of semimajor axis drift in any given data set, a signal-to-noise metric, and orbital coverage requirements. In 42 cases, the observed drifts ({approx}10{sup -3} AU Myr{sup -1}) agree well with numerical estimates of Yarkovsky drifts. This agreement suggests that the Yarkovsky effect is the dominant non-gravitational process affecting these orbits, and allows us to derive constraints on asteroid physical properties. In 12 cases, the drifts exceed nominal Yarkovsky predictions, which could be due to inaccuracies in our knowledge of physical properties, faulty astrometry, or modeling errors. If these high rates cannot be ruled out by further observations or improvements in modeling, they would be indicative of the presence of an additional non-gravitational force, such as that resulting from a loss of mass of order a kilogram per second. We define the Yarkovsky efficiency f{sub Y} as the ratio of the change in orbital energy to incident solar radiation energy, and we find that typical Yarkovsky efficiencies are {approx}10{sup -5}.

  19. Dual capacity compressor with reversible motor and controls arrangement therefor

    DOE Patents [OSTI]

    Sisk, Francis J.

    1980-12-02

    A hermetic reciprocating compressor such as may be used in heat pump applications is provided for dual capacity operation by providing the crankpin of the crankshaft with an eccentric ring rotatably mounted thereon, and with the end of the connecting rod opposite the piston encompassing the outer circumference of the eccentric ring, with means limiting the rotation of the eccentric ring upon the crankpin between one end point and an opposite angularly displaced end point to provide different values of eccentricity depending upon which end point the eccentric ring is rotated to upon the crankpin, and a reversible motor in the hermetic shell of the compressor for rotating the crankshaft, the motor operating in one direction effecting the angular displacement of the eccentric ring relative to the crankpin to the one end point, and in the opposite direction effecting the angular displacement of the eccentric ring relative to the crankpin to the opposite end point, this arrangement automatically giving different stroke lengths depending upon the direction of motor rotation. The mechanical structure of the arrangement may take various forms including at least one in which any impact of reversal is reduced by utilizing lubricant passages and chambers at the interface area of the crankpin and eccentric ring to provide a dashpot effect. In the main intended application of the arrangement according to the invention, that is, in a refrigerating or air conditioning system, it is desirable to insure a delay during reversal of the direction of compressor operation. A control arrangement is provided in which the control system controls the direction of motor operation in accordance with temperature conditions, the system including control means for effecting operation in a low capacity direction or alternatively in a high capacity direction in response to one set, and another set, respectively, of temperature conditions and with timer means delaying a restart of the compressor

  20. The Case for the Dual Halo of the Milky Way

    SciTech Connect (OSTI)

    Beers, Timothy C.; Carollo, Daniela; Ivezic, Zeljko; An, Deokkeun; Chiba, Masashi; Norris, John E.; Freeman, Ken C.; Lee, Young Sun; Munn, Jeffrey A.; Fiorentin, Paola Re; Sivarani, Thirupathi; /Bangalore, Indian Inst. Astrophys. /Kentucky U.

    2011-04-01

    similar to those previously derived. An additional test of the reality of the retrograde signature is provided, based exclusively on the observed proper motions of low-metallicity stars. Further evidence for a complex halo comes from inspection of the metallicity distribution function of the Carollo et al. sample as a function of distance from the Galactic plane. We summarize additional lines of evidence for a dual halo, based on different stellar samples from the SDSS and other surveys. We conclude that the overwhelming body of evidence rejects the single-halo interpretation beyond reasonable doubt.

  1. Turbine airfoil with dual wall formed from inner and outer layers separated by a compliant structure

    DOE Patents [OSTI]

    Campbell; Christian X. , Morrison; Jay A.

    2011-12-20

    A turbine airfoil usable in a turbine engine with a cooling system and a compliant dual wall configuration configured to enable thermal expansion between inner and outer layers while eliminating stress formation is disclosed. The compliant dual wall configuration may be formed a dual wall formed from inner and outer layers separated by a compliant structure. The compliant structure may be configured such that the outer layer may thermally expand without limitation by the inner layer. The compliant structure may be formed from a plurality of pedestals positioned generally parallel with each other. The pedestals may include a first foot attached to a first end of the pedestal and extending in a first direction aligned with the outer layer, and may include a second foot attached to a second end of the pedestal and extending in a second direction aligned with the inner layer.

  2. Dual fuel Russian urban transit buses: Economical reduced emissions. Export trade information

    SciTech Connect (OSTI)

    1998-01-01

    This study, conducted by Caterpillar, was funded by the US Trade and Development Agency. The scope of this project was to examine the financial and environmental aspects of introducing new alternative fuel engines to the buses of Russia`s public transportation system. The report consists of the following: (1) executive summary; (2) background/overview; (3) 3306 design, development, test; (4) electronic governed engines; (5) Moscow bus testing; (6) conclusions; (7) appendices. The appendices include: (1) Caterpillar emissions lab report; (2) dyno tests -- dual fuel data sheets; (3) 3360 horizontal engine lub tilt test; (4) 1000 hour endurance test -- engine operator sheets; (5) 1000 hour endurance test -- 250 hour check; (6) Caterpillar dual fuel electronic engines; (7) product description -- dual fuel electronic governed engines; (8) California Environmental Protection Agency -- certification of caterpillar electronic governed engines; (9) annual payback data.

  3. Measurement of breast tissue composition with dual energy cone-beam computed tomography: A postmortem study

    SciTech Connect (OSTI)

    Ding Huanjun; Ducote, Justin L.; Molloi, Sabee

    2013-06-15

    Purpose: To investigate the feasibility of a three-material compositional measurement of water, lipid, and protein content of breast tissue with dual kVp cone-beam computed tomography (CT) for diagnostic purposes. Methods: Simulations were performed on a flat panel-based computed tomography system with a dual kVp technique in order to guide the selection of experimental acquisition parameters. The expected errors induced by using the proposed calibration materials were also estimated by simulation. Twenty pairs of postmortem breast samples were imaged with a flat-panel based dual kVp cone-beam CT system, followed by image-based material decomposition using calibration data obtained from a three-material phantom consisting of water, vegetable oil, and polyoxymethylene plastic. The tissue samples were then chemically decomposed into their respective water, lipid, and protein contents after imaging to allow direct comparison with data from dual energy decomposition. Results: Guided by results from simulation, the beam energies for the dual kVp cone-beam CT system were selected to be 50 and 120 kVp with the mean glandular dose divided equally between each exposure. The simulation also suggested that the use of polyoxymethylene as the calibration material for the measurement of pure protein may introduce an error of -11.0%. However, the tissue decomposition experiments, which employed a calibration phantom made out of water, oil, and polyoxymethylene, exhibited strong correlation with data from the chemical analysis. The average root-mean-square percentage error for water, lipid, and protein contents was 3.58% as compared with chemical analysis. Conclusions: The results of this study suggest that the water, lipid, and protein contents can be accurately measured using dual kVp cone-beam CT. The tissue compositional information may improve the sensitivity and specificity for breast cancer diagnosis.

  4. Combustion and Emissions Performance of Dual-Fuel Gasoline and Diesel HECC

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    on a Multi-Cylinder Light Duty Diesel Engine | Department of Energy Combustion and Emissions Performance of Dual-Fuel Gasoline and Diesel HECC on a Multi-Cylinder Light Duty Diesel Engine Combustion and Emissions Performance of Dual-Fuel Gasoline and Diesel HECC on a Multi-Cylinder Light Duty Diesel Engine Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. p-06_curran.pdf (416.42 KB) More Documents

  5. Control Strategy for a Dual Loop EGR System to Meet Euro 6 and Beyond |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Control Strategy for a Dual Loop EGR System to Meet Euro 6 and Beyond Control Strategy for a Dual Loop EGR System to Meet Euro 6 and Beyond Presentation given at the 2009 DEER Conference. This presentation focues on EGR and Boost systems for reducing the cost and lowering emissions of diesel engines. deer09_czarnowski.pdf (2.06 MB) More Documents & Publications Can Future Emissions Limits be Met with a Hybrid EGR System Alone? Strategies for In-Cylinder Reductions to

  6. Dual-rotor, radial-flux, toroidally-wound, permanent-magnet machine

    DOE Patents [OSTI]

    Qu, Ronghai; Lipo, Thomas A.

    2005-08-02

    The present invention provides a novel dual-rotor, radial-flux, toroidally-wound, permanent-magnet machine. The present invention improves electrical machine torque density and efficiency. At least one concentric surface-mounted permanent magnet dual-rotor is located inside and outside of a torus-shaped stator with back-to-back windings, respectively. The machine substantially improves machine efficiency by reducing the end windings and boosts the torque density by at least doubling the air gap and optimizing the machine aspect ratio.

  7. Pre-Combustion Carbon Dioxide Capture by a New Dual Phase Ceramic-Carbonate Membrane Reactor

    SciTech Connect (OSTI)

    Lin, Jerry

    2014-09-30

    This report documents synthesis, characterization and carbon dioxide permeation and separation properties of a new group of ceramic-carbonate dual-phase membranes and results of a laboratory study on their application for water gas shift reaction with carbon dioxide separation. A series of ceramic-carbonate dual phase membranes with various oxygen ionic or mixed ionic and electronic conducting metal oxide materials in disk, tube, symmetric, and asymmetric geometric configurations was developed. These membranes, with the thickness of 10 μm to 1.5 mm, show CO2 permeance in the range of 0.5-5×10-7 mol·m-2·s-1·Pa-1 in 500-900oC and measured CO2/N2 selectivity of up to 3000. CO2 permeation mechanism and factors that affect CO2 permeation through the dual-phase membranes have been identified. A reliable CO2 permeation model was developed. A robust method was established for the optimization of the microstructures of ceramic-carbonate membranes. The ceramic-carbonate membranes exhibit high stability for high temperature CO2 separations and water gas shift reaction. Water gas shift reaction in the dual-phase membrane reactors was studied by both modeling and experiments. It is found that high temperature syngas water gas shift reaction in tubular ceramic-carbonate dual phase membrane reactor is feasible even without catalyst. The membrane reactor exhibits good CO2 permeation flux, high thermal and chemical stability and high thermal shock resistance. Reaction and separation conditions in the membrane reactor to produce hydrogen of 93% purity and CO2 stream of >95% purity, with 90% CO2 capture have been identified. Integration of the ceramic-carbonate dual-phase membrane reactor with IGCC process for carbon dioxide capture was analyzed. A methodology was developed to identify optimum operation conditions for a membrane tube of given dimensions that would treat coal syngas with targeted performance. The calculation results show that the dual-phase membrane reactor could

  8. Target duality in N= 8 superconformal mechanics and the coupling of dual pairs

    SciTech Connect (OSTI)

    Gonzales, Marcelo; Lechtenfeld, Olaf; Centre for Quantum Engineering and Space-Time Research, Leibniz Universität Hannover, Welfengarten 1, 30167 Hannover

    2013-07-15

    We couple dual pairs of N= 8 superconformal mechanics with conical targets of dimension d and 8−d. The superconformal coupling generates an oscillator-type potential on each of the two target factors, with a frequency depending on the respective dual coordinates. In the case of the inhomogeneous (3,8,5) model, which entails a monopole background, it is necessary to add an extra supermultiplet of constants for half of the supersymmetry. The N= 4 analog, joining an inhomogeneous (1,4,3) with a (3,4,1) multiplet, is also analyzed in detail.

  9. Heavy-duty H2-Diesel Dual Fuel Engines | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    duty H2-Diesel Dual Fuel Engines Heavy-duty H2-Diesel Dual Fuel Engines Brake thermal efficiency can be improved with the addition of a large amount of hydrogen at medium to high loads deer09_li.pdf (37.32 KB) More Documents & Publications Evaluation of NTE Windows and a Work-Based Method to Determine In-Use Emissions of a Heavy-Duty Diesel Engine Status of APBF-DEC NOx Adsorber/DPF Projects Integrated Engine and Aftertreatment Technology Roadmap for EPA 2010 Heavy-duty Emissions Regulations

  10. A study on dual readout crystal calorimeter for hadron and jet energy measurement at a future lepton collider

    SciTech Connect (OSTI)

    Yeh, G.P.; /Fermilab

    2010-01-01

    Studies of requirements and specifications of crystals are necessary to develop a new generation of crystals for dual readout crystal hadron or total absorption calorimeter. This is a short and basic study of the characteristics and hadron energy measurement of PbWO4 and BGO crystals for scintillation and Cerenkov Dual Readout hadron calorimeter.

  11. MO-E-17A-01: BEST IN PHYSICS (IMAGING) - Calculating SSDE From CT Exams Using Size Data Available in the DICOM Header of CT Localizer Radiographs

    SciTech Connect (OSTI)

    McMillan, K; Bostani, M; McNitt-Gray, M; McCollough, C

    2014-06-15

    Purpose: To demonstrate the feasibility of using existing data stored within the DICOM header of certain CT localizer radiographs as a patient size metric for calculating CT size-specific dose estimates (SSDE). Methods: For most Siemens CT scanners, the CT localizer radiograph (topogram) contains a private DICOM field that stores an array of numbers describing AP and LAT attenuation-based measures of patient dimension. The square root of the product of the AP and LAT size data, which provides an estimate of water-equivalent-diameter (WED), was calculated retrospectively from topogram data of 20 patients who received clinically-indicated abdomen/pelvis (n=10) and chest (n=10) scans (WED-topo). In addition, slice-by-slice water-equivalent-diameter (WED-image) and effective diameter (ED-image) values were calculated from the respective image data. Using TG-204 lookup tables, size-dependent conversion factors were determined based upon WED-topo, WED-image and ED-image values. These conversion factors were used with the reported CTDIvol to calculate slice-by-slice SSDE for each method. Averaging over all slices, a single SSDE value was determined for each patient and size metric. Patientspecific SSDE and CTDIvol values were then compared with patientspecific organ doses derived from detailed Monte Carlo simulations of fixed tube current scans. Results: For abdomen/pelvis scans, the average difference between liver dose and CTDIvol, SSDE(WED-topo), SSDE(WED-image), and SSDE(ED-image) was 18.70%, 8.17%, 6.84%, and 7.58%, respectively. For chest scans, the average difference between lung dose and CTDIvol, SSDE(WED-topo), SSDE(WED-image), and SSDE(ED-image) was 25.80%, 3.33%, 4.11%, and 7.66%, respectively. Conclusion: SSDE calculated using WED derived from data in the DICOM header of the topogram was comparable to SSDE calculated using WED and ED derived from axial images; each of these estimated organ dose to within 10% for both abdomen/pelvis and chest CT examinations

  12. System-Level Logistics for Dual Purpose Canister Disposal

    SciTech Connect (OSTI)

    Kalinina, Elena A.

    2014-06-03

    The analysis presented in this report investigated how the direct disposal of dual purpose canisters (DPCs) may be affected by the use of standard transportation aging and disposal canisters (STADs), early or late start of the repository, and the repository emplacement thermal power limits. The impacts were evaluated with regard to the availability of the DPCs for emplacement, achievable repository acceptance rates, additional storage required at an interim storage facility (ISF) and additional emplacement time compared to the corresponding repackaging scenarios, and fuel age at emplacement. The result of this analysis demonstrated that the biggest difference in the availability of UNF for emplacement between the DPC-only loading scenario and the DPCs and STADs loading scenario is for a repository start date of 2036 with a 6 kW thermal power limit. The differences are also seen in the availability of UNF for emplacement between the DPC-only loading scenario and the DPCs and STADs loading scenario for the alternative with a 6 kW thermal limit and a 2048 start date, and for the alternatives with a 10 kW thermal limit and 2036 and 2048 start dates. The alternatives with disposal of UNF in both DPCs and STADs did not require additional storage, regardless of the repository acceptance rate, as compared to the reference repackaging case. In comparison to the reference repackaging case, alternatives with the 18 kW emplacement thermal limit required little to no additional emplacement time, regardless of the repository start time, the fuel loading scenario, or the repository acceptance rate. Alternatives with the 10 kW emplacement thermal limit and the DPCs and STADs fuel loading scenario required some additional emplacement time. The most significant decrease in additional emplacement time occurred in the alternative with the 6 kW thermal limit and the 2036 repository starting date. The average fuel age at emplacement ranges from 46 to 88 years. The maximum fuel age at

  13. Iterative image-domain decomposition for dual-energy CT

    SciTech Connect (OSTI)

    Niu, Tianye; Dong, Xue; Petrongolo, Michael; Zhu, Lei

    2014-04-15

    Purpose: Dual energy CT (DECT) imaging plays an important role in advanced imaging applications due to its capability of material decomposition. Direct decomposition via matrix inversion suffers from significant degradation of image signal-to-noise ratios, which reduces clinical values of DECT. Existing denoising algorithms achieve suboptimal performance since they suppress image noise either before or after the decomposition and do not fully explore the noise statistical properties of the decomposition process. In this work, the authors propose an iterative image-domain decomposition method for noise suppression in DECT, using the full variance-covariance matrix of the decomposed images. Methods: The proposed algorithm is formulated in the form of least-square estimation with smoothness regularization. Based on the design principles of a best linear unbiased estimator, the authors include the inverse of the estimated variance-covariance matrix of the decomposed images as the penalty weight in the least-square term. The regularization term enforces the image smoothness by calculating the square sum of neighboring pixel value differences. To retain the boundary sharpness of the decomposed images, the authors detect the edges in the CT images before decomposition. These edge pixels have small weights in the calculation of the regularization term. Distinct from the existing denoising algorithms applied on the images before or after decomposition, the method has an iterative process for noise suppression, with decomposition performed in each iteration. The authors implement the proposed algorithm using a standard conjugate gradient algorithm. The method performance is evaluated using an evaluation phantom (Catphan600) and an anthropomorphic head phantom. The results are compared with those generated using direct matrix inversion with no noise suppression, a denoising method applied on the decomposed images, and an existing algorithm with similar formulation as the

  14. A Preliminary Cost Study of the Dual Mode Inverter Controller

    SciTech Connect (OSTI)

    McKeever, J.W.

    2005-01-28

    In 1998, the Power Electronics and Electric Machinery Research Center (PEEMRC) at the Oak Ridge National Laboratory (ORNL) started a program to investigate alternate field weakening schemes for permanent magnet (PM) motors. The adjective ''alternate'' was used because at that time, outside research emphasis was on motors with interior-mounted PMs (IPMs). The PEEMRC emphasis was placed on motors with surface-mounted PMs (SPMs) because of the relative ease of manufacturing SPM motors compared with the IPM motors. Today the PEEMRC is continuing research on SPMs while examining the IPMs that have been developed by industry. Out of this task--the goal of which was to find ways to drive PM motors that inherently have low inductance at high speeds where their back-emf exceeds the supply voltage--ORNL developed and demonstrated the dual mode inverter control (DMIC) [1,2] method of field weakening for SPM motors. The predecessor of DMIC is conventional phase advance (CPA), which was developed by UQM Technologies, Inc. [3]. Fig. 1 shows the three sets of anti-parallel thyristors in the dashed box that comprise the DMIC. If one removes the dashed box by shorting each set of anti-parallel thyristors, the configuration becomes a conventional full bridge inverter on the left driving a three phase motor on the right. CPA may be used to drive this configuration ORNL's initial analyses of CPA and DMIC were based on driving motors with trapezoidal back-emfs [4-6], obtained using double layer lapped stator windings with one slot per pole per phase. A PM motor with a sinusoidal back-emf obtained with two poles per slot per phase has been analyzed under DMIC operation as a University of Tennessee-Knoxville (UTK) doctoral dissertation [7]. In the process of this research, ORNL has completed an analysis that explains and quantifies the role of inductance in these methods of control. The Appendix includes information on the equations for the three components of phase inductance, L{sub gap

  15. Development and Verification of a Computational Fluid Dynamics Model of a Horizontal-Axis Tidal Current Turbine

    SciTech Connect (OSTI)

    Lawson, M. J.; Li, Y.; Sale, D. C.

    2011-10-01

    This paper describes the development of a computational fluid dynamics (CFD) methodology to simulate the hydrodynamics of horizontal-axis tidal current turbines. Qualitative measures of the CFD solutions were independent of the grid resolution. Conversely, quantitative comparisons of the results indicated that the use of coarse computational grids results in an under prediction of the hydrodynamic forces on the turbine blade in comparison to the forces predicted using more resolved grids. For the turbine operating conditions considered in this study, the effect of the computational timestep on the CFD solution was found to be minimal, and the results from steady and transient simulations were in good agreement. Additionally, the CFD results were compared to corresponding blade element momentum method calculations and reasonable agreement was shown. Nevertheless, we expect that for other turbine operating conditions, where the flow over the blade is separated, transient simulations will be required.

  16. Creating orbiting vorticity vectors in magnetic particle suspensions through field symmetry transitions–a route to multi-axis mixing

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Martin, James E.; Solis, Kyle Jameson

    2015-11-09

    It has recently been reported that two types of triaxial electric or magnetic fields can drive vorticity in dielectric or magnetic particle suspensions, respectively. The first type-symmetry -- breaking rational fields -- consists of three mutually orthogonal fields, two alternating and one dc, and the second type -- rational triads -- consists of three mutually orthogonal alternating fields. In each case it can be shown through experiment and theory that the fluid vorticity vector is parallel to one of the three field components. For any given set of field frequencies this axis is invariant, but the sign and magnitude ofmore » the vorticity (at constant field strength) can be controlled by the phase angles of the alternating components and, at least for some symmetry-breaking rational fields, the direction of the dc field. In short, the locus of possible vorticity vectors is a 1-d set that is symmetric about zero and is along a field direction. In this paper we show that continuous, 3-d control of the vorticity vector is possible by progressively transitioning the field symmetry by applying a dc bias along one of the principal axes. Such biased rational triads are a combination of symmetry-breaking rational fields and rational triads. A surprising aspect of these transitions is that the locus of possible vorticity vectors for any given field bias is extremely complex, encompassing all three spatial dimensions. As a result, the evolution of a vorticity vector as the dc bias is increased is complex, with large components occurring along unexpected directions. More remarkable are the elaborate vorticity vector orbits that occur when one or more of the field frequencies are detuned. As a result, these orbits provide the basis for highly effective mixing strategies wherein the vorticity axis periodically explores a range of orientations and magnitudes.« less

  17. Creating orbiting vorticity vectors in magnetic particle suspensions through field symmetry transitions–a route to multi-axis mixing

    SciTech Connect (OSTI)

    Martin, James E.; Solis, Kyle Jameson

    2015-11-09

    It has recently been reported that two types of triaxial electric or magnetic fields can drive vorticity in dielectric or magnetic particle suspensions, respectively. The first type-symmetry -- breaking rational fields -- consists of three mutually orthogonal fields, two alternating and one dc, and the second type -- rational triads -- consists of three mutually orthogonal alternating fields. In each case it can be shown through experiment and theory that the fluid vorticity vector is parallel to one of the three field components. For any given set of field frequencies this axis is invariant, but the sign and magnitude of the vorticity (at constant field strength) can be controlled by the phase angles of the alternating components and, at least for some symmetry-breaking rational fields, the direction of the dc field. In short, the locus of possible vorticity vectors is a 1-d set that is symmetric about zero and is along a field direction. In this paper we show that continuous, 3-d control of the vorticity vector is possible by progressively transitioning the field symmetry by applying a dc bias along one of the principal axes. Such biased rational triads are a combination of symmetry-breaking rational fields and rational triads. A surprising aspect of these transitions is that the locus of possible vorticity vectors for any given field bias is extremely complex, encompassing all three spatial dimensions. As a result, the evolution of a vorticity vector as the dc bias is increased is complex, with large components occurring along unexpected directions. More remarkable are the elaborate vorticity vector orbits that occur when one or more of the field frequencies are detuned. As a result, these orbits provide the basis for highly effective mixing strategies wherein the vorticity axis periodically explores a range of orientations and magnitudes.

  18. Comparison of Propane and Methane Performance and Emissions in a Turbocharged Direct Injection Dual Fuel Engine

    SciTech Connect (OSTI)

    Gibson, C. M.; Polk, A. C.; Shoemaker, N. T.; Srinivasan, K. K.; Krishnan, S. R.

    2011-01-01

    With increasingly restrictive NO x and particulate matter emissions standards, the recent discovery of new natural gas reserves, and the possibility of producing propane efficiently from biomass sources, dual fueling strategies have become more attractive. This paper presents experimental results from dual fuel operation of a four-cylinder turbocharged direct injection (DI) diesel engine with propane or methane (a natural gas surrogate) as the primary fuel and diesel as the ignition source. Experiments were performed with the stock engine control unit at a constant speed of 1800 rpm, and a wide range of brake mean effective pressures (BMEPs) (2.7-11.6 bars) and percent energy substitutions (PESs) of C 3 H 8 and CH 4. Brake thermal efficiencies (BTEs) and emissions (NO x, smoke, total hydrocarbons (THCs), CO, and CO 2) were measured. Maximum PES levels of about 80-95% with CH 4 and 40-92% with C 3 H 8 were achieved. Maximum PES was limited by poor combustion efficiencies and engine misfire at low loads for both C 3 H 8 and CH 4, and the onset of knock above 9 bar BMEP for C 3 H 8. While dual fuel BTEs were lower than straight diesel BTEs at low loads, they approached diesel BTE values at high loads. For dual fuel operation, NO x and smoke reductions (from diesel values) were as high as 66-68% and 97%, respectively, but CO and THC emissions were significantly higher with increasing PES at all engine loads

  19. Crosstalk elimination in the detection of dual-beam optical tweezers by spatial filtering

    SciTech Connect (OSTI)

    Ott, Dino; Oddershede, Lene B.; Reihani, S. Nader S.

    2014-05-15

    In dual-beam optical tweezers, the accuracy of position and force measurements is often compromised by crosstalk between the two detected signals, this crosstalk leading to systematic and significant errors on the measured forces and distances. This is true both for dual-beam optical traps where the splitting of the two traps is done by polarization optics and for dual optical traps constructed by other methods, e.g., holographic tweezers. If the two traps are orthogonally polarized, most often crosstalk is minimized by inserting polarization optics in front of the detector; however, this method is not perfect because of the de-polarization of the trapping beam introduced by the required high numerical aperture optics. Here we present a simple and easy-to-implement method to efficiently eliminate crosstalk. The method is based on spatial filtering by simply inserting a pinhole at the correct position and is highly compatible with standard back focal plane photodiode based detection of position and force. Our spatial filtering method reduces crosstalk up to five times better than polarization filtering alone. The effectiveness is dependent on pinhole size and distance between the traps and is here quantified experimentally and reproduced by theoretical modeling. The method here proposed will improve the accuracy of force-distance measurements, e.g., of single molecules, performed by dual-beam optical traps and hence give much more scientific value for the experimental efforts.

  20. Inferior Pancreaticoduodenal Artery Aneurysms Associated with Occlusive Lesions of the Celiac Axis: Diagnosis, Treatment Options, Outcomes, and Review of the Literature

    SciTech Connect (OSTI)

    Flood, Karen Nicholson, Anthony A.

    2013-06-15

    Purpose. To describe the presentation, treatment, and outcomes for 14 patients with aneurysms of the inferior pancreaticoduodenal arteries associated with occlusive lesions of the celiac axis, and to review the literature for similar cases. Methods, Over a period of 12 years, 14 patients (10 women and 4 men) ranging in age from 26 to 50 (mean 46) years were demonstrated to have aneurysms of the inferior pancreaticoduodenal artery origin associated with stenosis or occlusion of the celiac axis. All patients were treated by a combination of surgery and interventional radiology. Results. Outcome data collected between 3 months and 4 years (mean 2 years) demonstrated that all aneurysms remained excluded, and all 14 patients were well. The 49 case reports in the literature confirm the findings of this cohort. Conclusion. In inferior pancreaticoduodenal artery aneurysm resulting from celiac occlusive disease, endovascular treatment is best achieved by stenting the celiac axis and/or embolizing the aneurysm when necessary.

  1. Method and device for determining the position of a cutting tool relative to the rotational axis of a spindle-mounted workpiece

    DOE Patents [OSTI]

    Williams, Richard R.

    1982-01-01

    The present invention is directed to a method and device for determining the location of a cutting tool with respect to the rotational axis of a spindle-mounted workpiece. A vacuum cup supporting a machinable sacrifical pin is secured to the workpiece at a location where the pin will project along and encompass the rotational axis of the workpiece. The pin is then machined into a cylinder. The position of the surface of the cutting tool contacting the machine cylinder is spaced from the rotational aixs of the workpiece a distance equal to the radius of the cylinder.

  2. One-Axis Trackers -- Improved Reliability, Durability, Performance, and Cost Reduction; Final Subcontract Technical Status Report, 2 May 2006 - 31 August 2007

    SciTech Connect (OSTI)

    Shingleton, J.

    2008-02-01

    The overall objective of this subcontract is to reduce the total cost of electricity generated by single-axis tracking solar energy systems for utility and other large-scale commercial applications by improving performance and reliability and by reducing installation time, cost, and environmental impact.

  3. Development and Verification of a Computational Fluid Dynamics Model of a Horizontal-Axis Tidal Current Turbine

    SciTech Connect (OSTI)

    Lawson, Mi. J.; Li, Y.; Sale, D. C.

    2011-01-01

    This paper describes the development of a computational fluid dynamics (CFD) methodology to simulate the hydrodynamics of horizontal-axis tidal current turbines (HATTs). First, an HATT blade was designed using the blade element momentum method in conjunction with a genetic optimization algorithm. Several unstructured computational grids were generated using this blade geometry and steady CFD simulations were used to perform a grid resolution study. Transient simulations were then performed to determine the effect of time-dependent flow phenomena and the size of the computational timestep on the numerical solution. Qualitative measures of the CFD solutions were independent of the grid resolution. Conversely, quantitative comparisons of the results indicated that the use of coarse computational grids results in an under prediction of the hydrodynamic forces on the turbine blade in comparison to the forces predicted using more resolved grids. For the turbine operating conditions considered in this study, the effect of the computational timestep on the CFD solution was found to be minimal, and the results from steady and transient simulations were in good agreement. Additionally, the CFD results were compared to corresponding blade element momentum method calculations and reasonable agreement was shown. Nevertheless, we expect that for other turbine operating conditions, where the flow over the blade is separated, transient simulations will be required.

  4. Status of Advanced Tokamak Scenario Modeling with Off-Axis Electron Cyclotron Current Drive in DIII-D

    SciTech Connect (OSTI)

    M. Murakami; H.E. St.John; T.A. Casper; M.S. Chu; J.C. DeBoo; C.M. Greenfield; J.E. Kinsey; L.L. Lao; R.J. La Haye; Y.R. Lin-Liu; T.C. Luce; P.A. Politzer; B.W. Rice; G.M. Staebler; T.S. Taylor; M.R. Wade

    1999-12-01

    The status of modeling work focused on developing the advanced tokamak scenarios in DIII-D is discussed. The objectives of the work are two-fold: (1) to develop AT scenarios with ECCD using time-dependent transport simulations, coupled with heating and current drive models, consistent with MHD equilibrium and stability; and (2) to use time-dependent simulations to help plan experiments and to understand the key physics involved. Time-dependent simulations based on transport coefficients derived from experimentally achieved target discharges are used to perform AT scenario modeling. The modeling indicates off-axis ECCD with approximately 3 MW absorbed power can maintain high-performance discharges with q{sub min} > 1 for 5 to 10 s. The resultant equilibria are calculated to be stable to n = 1 pressure driven modes. The plasma is well into the second stability regime for high-n ballooning modes over a large part of the plasma volume. The role of continuous localized ECCD is studied for stabilizing m/n = 2/1 tearing modes. The progress towards validating current drive and transport models, consistent with experimental results, and developing self-consistent, integrated high performance AT scenarios is discussed.

  5. An indirect method of studying band alignments in nBn photodetectors using off-axis electron holography

    SciTech Connect (OSTI)

    Shen, Xiao-Meng; He, Zhao-Yu; Liu, Shi; Lin, Zhi-Yuan; Zhang, Yong-Hang; Smith, David J.; McCartney, Martha R.

    2015-09-21

    Mid-wave and long-wave infrared nBn photodetectors with absorbers consisting of InAs/InAsSb superlattices and barriers consisting of InAs/AlGaSb(As) superlattices were grown using molecular beam epitaxy. High-resolution X-ray diffraction showing significant differences in Ga composition in the barrier layer, and different dark current behavior at 77 K, suggested the possibility of different types of band alignments between the barrier layer and the absorber for the mid- and long-wave infrared samples. Examination of the barrier layers using off-axis electron holography showed the presence of positive charge with an estimated density of 1.8 × 10{sup 17}/cm{sup 3} in the mid-wave sample as a result of a type-II band alignment, whereas negligible charge was detected in the long-wave sample, consistent with a type-I band alignment.

  6. vertical axis wind turbine

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    verification Nuclear Verification Challenge: Maintain the U.S. ability to monitor and verify nuclear reduction agreements and detect violations of treaties and other nuclear nonproliferation commitments. Solution: Develop and deploy measures to ensure verifiable compliance with treaties and other international agreements,... International Nuclear Safeguards Challenge: Detect/deter undeclared nuclear materials and activities. Solution: Build capacity of the International Atomic Energy Agency and

  7. Pyroelectric-field driven defects diffusion along c-axis in ZnO nanobelts under high-energy electron beam irradiation

    SciTech Connect (OSTI)

    Ding, Yong Liu, Ying; Niu, Simiao; Wu, Wenzhuo; Wang, Zhong Lin

    2014-10-21

    When ZnO nanobelts are exposed to a high-dose electron probe of several nanometers to hundred nanometers in diameter inside a transmission electron microscope, due to the radiolysis effect, part of oxygen atoms will be ejected into the vacuum and leaving a Zn-ion rich surface with a pit appearance at both the electron-entrance and electron-exit surfaces. At the same time, a temperature distribution is created around the electron probe due to local beam heating effect, which generates a unidirectional pyroelectric field. This pyroelectric field is strong enough to drive Zn ions moving along its positive c-axis direction as interstitial ions. In the first case, for the ZnO nanobelts with c-axis lie in their large surfaces, defects due to the aggregation of Zn interstitial ions will be formed at some distances of 3050 nm approximately along the c-axis direction from the electron beam illuminated area. Alternatively, for the ZnO nanobelts with (0001) planes as their large surfaces, the incident electron beam is along its c-axis and the generated pyroelectric field will drive the interstitial Zn-ions to aggregate at the Zn terminated (0001) surface where the local electrical potential is the lowest. Such electron beam induced damage in ZnO nanostructures is suggested as a result of Zn ion diffusion driven by the temperature gradient induced pyroelectric field along c-axis. Our study shows a radiation damage caused by electron beam in transmission electron microscopy, especially when the electron energy is high.

  8. Synthesis of ZSM-23/ZSM-22 intergrowth zeolite with a novel dual-template strategy

    SciTech Connect (OSTI)

    Wang, Bingchun, E-mail: wangbc@dicp.ac.cn [National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China) [National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Tian, Zhijian, E-mail: tianz@dicp.ac.cn [National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China) [National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Li, Peng; Wang, Lei; Xu, Yunpeng; Qu, Wei; Ma, Huaijun; Xu, Zhusheng [National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)] [National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Lin, Liwu [State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)] [State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)

    2009-12-15

    ZSM-23/ZSM-22 intergrowth zeolite with fixed proportion of 60%ZSM-23/40%ZSM-22 has been synthesized with a novel dual-template strategy. The products were characterized by X-ray diffraction and scanning electron microscopy. Dimethylamine and diethylamine were used together as a dual-template system. The molar ratio of diethylamine to dimethylamine, which was changed with the type of aluminum source, was the key factor for the synthesis of intergrowth zeolites. A molar ratio of diethylamine to dimethylamine of 1:24 could result in an ZSM-23/ZSM-22 intergrowth zeolite if aluminum sulfate was used as aluminum source, whereas a molar ratio of diethylamine to dimethylamine of 1:12 was required to get an ZSM-23/ZSM-22 intergrowth zeolite if sodium metaaluminate was used. Furthermore, fluoride anion could be involved in the process as a crystallization promoter.

  9. Cyclic Combustion Variations in Dual Fuel Partially Premixed Pilot-Ignited Natural Gas Engines

    SciTech Connect (OSTI)

    Srinivasan, K. K.; Krishnan, S. R.

    2012-05-09

    Dual fuel pilot ignited natural gas engines are identified as an efficient and viable alternative to conventional diesel engines. This paper examines cyclic combustion fluctuations in conventional dual fuel and in dual fuel partially premixed low temperature combustion (LTC). Conventional dual fueling with 95% (energy basis) natural gas (NG) substitution reduces NOx emissions by almost 90%t relative to straight diesel operation; however, this is accompanied by 98% increase in HC emissions, 10 percentage points reduction in fuel conversion efficiency (FCE) and 12 percentage points increase in COVimep. Dual fuel LTC is achieved by injection of a small amount of diesel fuel (2-3 percent on an energy basis) to ignite a premixed natural gas–air mixture to attain very low NOx emissions (less than 0.2 g/kWh). Cyclic variations in both combustion modes were analyzed by observing the cyclic fluctuations in start of combustion (SOC), peak cylinder pressures (Pmax), combustion phasing (Ca50), and the separation between the diesel injection event and Ca50 (termed “relative combustion phasing”). For conventional dual fueling, as % NG increases, Pmax decreases, SOC and Ca50 are delayed, and cyclic variations increase. For dual fuel LTC, as diesel injection timing is advanced from 20° to 60°BTDC, the relative combustion phasing is identified as an important combustion parameter along with SoC, Pmax, and CaPmax. For both combustion modes, cyclic variations were characterized by alternating slow and fast burn cycles, especially at high %NG and advanced injection timings. Finally

  10. An image quality comparison of standard and dual-side read CR systems for pediatric radiology

    SciTech Connect (OSTI)

    Monnin, P.; Holzer, Z.; Wolf, R.; Neitzel, U.; Vock, P.; Gudinchet, F.; Verdun, F.R.

    2006-02-15

    An objective analysis of image quality parameters was performed for a computed radiography (CR) system using both standard single-side and prototype dual-side read plates. The pre-sampled modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE) for the systems were determined at three different beam qualities representative of pediatric chest radiography, at an entrance detector air kerma of 5 {mu}Gy. The NPS and DQE measurements were realized under clinically relevant x-ray spectra for pediatric radiology, including x-ray scatter radiations. Compared to the standard single-side read system, the MTF for the dual-side read system is reduced, but this is offset by a significant decrease in image noise, resulting in a marked increase in DQE (+40%) in the low spatial frequency range. Thus, for the same image quality, the new technology permits the CR system to be used at a reduced dose level.

  11. DualTrust: A Distributed Trust Model for Swarm-Based Autonomic Computing Systems

    SciTech Connect (OSTI)

    Maiden, Wendy M.; Dionysiou, Ioanna; Frincke, Deborah A.; Fink, Glenn A.; Bakken, David E.

    2011-02-01

    For autonomic computing systems that utilize mobile agents and ant colony algorithms for their sensor layer, trust management is important for the acceptance of the mobile agent sensors and to protect the system from malicious behavior by insiders and entities that have penetrated network defenses. This paper examines the trust relationships, evidence, and decisions in a representative system and finds that by monitoring the trustworthiness of the autonomic managers rather than the swarming sensors, the trust management problem becomes much more scalable and still serves to protect the swarm. We then propose the DualTrust conceptual trust model. By addressing the autonomic manager’s bi-directional primary relationships in the ACS architecture, DualTrust is able to monitor the trustworthiness of the autonomic managers, protect the sensor swarm in a scalable manner, and provide global trust awareness for the orchestrating autonomic manager.

  12. Bimodal wireless sensing with dual-channel wide bandgap heterostructure varactors

    SciTech Connect (OSTI)

    Deen, David A.; Osinsky, Andrei; Miller, Ross

    2014-03-03

    A capacitive wireless sensing scheme is developed that utilizes an AlN/GaN-based dual-channel varactor. The dual-channel heterostructure affords two capacitance plateaus within the capacitance-voltage (CV) characteristic, owing to the two parallel two-dimensional electron gases (2DEGs) located at respective AlN/GaN interfaces. The capacitance plateaus are leveraged for the definition of two resonant states of the sensor when implemented in an inductively-coupled resonant LRC network for wireless readout. The physics-based CV model is compared with published experimental results, which serve as a basis for the sensor embodiment. The bimodal resonant sensor is befitting for a broad application space ranging from gas, electrostatic, and piezoelectric sensors to biological and chemical detection.

  13. Protein–ligand interactions investigated by thermal shift assays (TSA) and dual polarization interferometry (DPI)

    SciTech Connect (OSTI)

    Grøftehauge, Morten K. Hajizadeh, Nelly R.; Swann, Marcus J.; Pohl, Ehmke

    2015-01-01

    The biophysical characterization of protein–ligand interactions in solution using techniques such as thermal shift assay, or on surfaces using, for example, dual polarization interferometry, plays an increasingly important role in complementing crystal structure determinations. Over the last decades, a wide range of biophysical techniques investigating protein–ligand interactions have become indispensable tools to complement high-resolution crystal structure determinations. Current approaches in solution range from high-throughput-capable methods such as thermal shift assays (TSA) to highly accurate techniques including microscale thermophoresis (MST) and isothermal titration calorimetry (ITC) that can provide a full thermodynamic description of binding events. Surface-based methods such as surface plasmon resonance (SPR) and dual polarization interferometry (DPI) allow real-time measurements and can provide kinetic parameters as well as binding constants. DPI provides additional spatial information about the binding event. Here, an account is presented of new developments and recent applications of TSA and DPI connected to crystallography.

  14. Dialing in the Properties of Dual Metallic-Insulating Materials | Argonne

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Laboratory Dialing in the Properties of Dual Metallic-Insulating Materials February 11, 2016 Tweet EmailPrint Materials that undergo metal-insulator transitions (MITs) are under intense study, because the transition is scientifically fascinating and technologically promising for various applications. Among these materials, VO2 has served as a prototype due to its favorable transition temperature. While the physical underpinnings of the transition have been heavily investigated

  15. On two-parameter models of photon cross sections: Application to dual-energy CT imaging

    SciTech Connect (OSTI)

    Williamson, Jeffrey F.; Li Sicong; Devic, Slobodan; Whiting, Bruce R.; Lerma, Fritz A.

    2006-11-15

    The goal of this study is to evaluate the theoretically achievable accuracy in estimating photon cross sections at low energies (20-1000 keV) from idealized dual-energy x-ray computed tomography (CT) images. Cross-section estimation from dual-energy measurements requires a model that can accurately represent photon cross sections of any biological material as a function of energy by specifying only two characteristic parameters of the underlying material, e.g., effective atomic number and density. This paper evaluates the accuracy of two commonly used two-parameter cross-section models for postprocessing idealized measurements derived from dual-energy CT images. The parametric fit model (PFM) accounts for electron-binding effects and photoelectric absorption by power functions in atomic number and energy and scattering by the Klein-Nishina cross section. The basis-vector model (BVM) assumes that attenuation coefficients of any biological substance can be approximated by a linear combination of mass attenuation coefficients of two dissimilar basis substances. Both PFM and BVM were fit to a modern cross-section library for a range of elements and mixtures representative of naturally occurring biological materials (Z=2-20). The PFM model, in conjunction with the effective atomic number approximation, yields estimated the total linear cross-section estimates with mean absolute and maximum error ranges of 0.6%-2.2% and 1%-6%, respectively. The corresponding error ranges for BVM estimates were 0.02%-0.15% and 0.1%-0.5%. However, for photoelectric absorption frequency, the PFM absolute mean and maximum errors were 10.8%-22.4% and 29%-50%, compared with corresponding BVM errors of 0.4%-11.3% and 0.5%-17.0%, respectively. Both models were found to exhibit similar sensitivities to image-intensity measurement uncertainties. Of the two models, BVM is the most promising approach for realizing dual-energy CT cross-section measurement.

  16. Nonlinear periodic waves solutions of the nonlinear self-dual network equations

    SciTech Connect (OSTI)

    Laptev, Denis V. Bogdan, Mikhail M.

    2014-04-15

    The new classes of periodic solutions of nonlinear self-dual network equations describing the breather and soliton lattices, expressed in terms of the Jacobi elliptic functions have been obtained. The dependences of the frequencies on energy have been found. Numerical simulations of soliton lattice demonstrate their stability in the ideal lattice and the breather lattice instability in the dissipative lattice. However, the lifetime of such structures in the dissipative lattice can be extended through the application of ac driving terms.

  17. Preliminary experimental investigation of a complex dual-band high power microwave source

    SciTech Connect (OSTI)

    Zhang, Xiaoping Li, Yangmei; Li, Zhiqiang; Zhong, Huihuang; Qian, Baoliang

    2015-10-15

    In order to promote the power conversion efficiency of a magnetically insulated transmission line oscillator (MILO) and obtain microwaves in dual bands, an axially extracted C-band virtual cathode oscillator (VCO) with multiple resonant cavities is introduced to partially utilize the load current of an S-band MILO. The formed novel dual-band high power microwave source called MILO and VCO is investigated with simulation and experimentally. A dual-band radiation antenna is designed to effectively radiate microwaves generated by the MILO and the VCO, respectively, while avoiding them being influenced by the microwave reflection and diffraction. The preliminary experimental results measured by the dual-band diagnostic system show that both the MILO and the VCO operate normally under repeated shots. A microwave of 2.1 GHz, 1.70 GW is generated from the MILO and a 0.37 GW microwave at frequencies of 4.1 GHz and 3.8 GHz is generated from the VCO under the condition of about 440 kV and 35 kA. Compared with a single MILO (10.6%), a MILO and VCO achieves higher total power and efficiency (13.4%) in both S and C bands, indicating that the load current of the MILO partially couples into the beam-wave interaction in the VCO and then contributes to the output microwaves. However, more works are needed regarding the spectrum purification of the VCO and promotion of the output power of both the MILO and the VCO.

  18. Beam dynamics in a long-pulse linear induction accelerator

    SciTech Connect (OSTI)

    Ekdahl, Carl; Abeyta, Epifanio O; Aragon, Paul; Archuleta, Rita; Cook, Gerald; Dalmas, Dale; Esquibel, Kevin; Gallegos, Robert A; Garnett, Robert; Harrison, James F; Johnson, Jeffrey B; Jacquez, Edward B; Mc Cuistian, Brian T; Montoya, Nicholas A; Nath, Subrato; Nielsen, Kurt; Oro, David; Prichard, Benjamin; Rose, Chris R; Sanchez, Manolito; Schauer, Martin M; Seitz, Gerald; Schulze, Martin; Bender, Howard A; Broste, William B; Carlson, Carl A; Frayer, Daniel K; Johnson, Douglas E; Tom, C Y; Trainham, C; Williams, John; Scarpetti, Raymond; Genoni, Thomas; Hughes, Thomas; Toma, Carsten

    2010-01-01

    The second axis of the Dual Axis Radiography of Hydrodynamic Testing (DARHT) facility produces up to four radiographs within an interval of 1.6 microseconds. It accomplishes this by slicing four micro-pulses out of a long 1.8-kA, 16.5-MeV electron beam pulse and focusing them onto a bremsstrahlung converter target. The long beam pulse is created by a dispenser cathode diode and accelerated by the unique DARHT Axis-II linear induction accelerator (LIA). Beam motion in the accelerator would be a problem for radiography. High frequency motion, such as from beam breakup instability, would blur the individual spots. Low frequency motion, such as produced by pulsed power variation, would produce spot to spot differences. In this article, we describe these sources of beam motion, and the measures we have taken to minimize it.

  19. Method for continuously recovering metals using a dual zone chemical reactor

    DOE Patents [OSTI]

    Bronson, Mark C. (Livermore, CA)

    1995-01-01

    A dual zone chemical reactor continuously processes metal-containing materials while regenerating and circulating a liquid carrier. The starting materials are fed into a first reaction zone of a vessel containing a molten salt carrier. The starting materials react to form a metal product and a by-product that dissolves in the molten salt that flows to a second reaction zone in the reaction vessel. The second reaction zone is partitioned from, but in fluid communication with, the first reaction zone. The liquid carrier continuously circulates along a pathway between the first reaction zone and the second reaction zone. A reactive gas is introduced into the second reaction zone to react with the reaction by-product to generate the molten salt. The metal product, the gaseous waste products, and the excess liquid carrier are removed without interrupting the operation of the reactor. The design of the dual zone reactor can be adapted to combine a plurality of liquid carrier regeneration zones in a multiple dual zone chemical reactor for production scale processing.

  20. An Analysis of Dual Zone Loading for Shipping Spent Nuclear Fuel

    SciTech Connect (OSTI)

    Allen, William Christopher; Yim, Man-Sung

    2007-07-01

    The bumps current fuel assembly designs can achieve exceeds the fuel assembly burnups the current fleet of shipping casks can ship. One method of handling this situation which has been proposed is regionalized loading. This concept involves administratively separating the fuel basket of a shipping cask into two or more regions and loading fuel with different burnup, cooling times and enrichments into these regions. To evaluate how regionalized loading patterns might affect shipping spent nuclear fuel in comparison to uniform loading, a test case study was performed using fuel assemblies discharged from an actual nuclear plant and a shipping cask licensed by the NRC. Using the same fuel assemblies and shipping cask, results were obtained assuming a uniform loading pattern and compared to the results obtained assuming a dual zone loading pattern. Source terms for the analysis were generated using SAS2 and the dose levels were calculated using MCNPS. The analysis showed that the dual zone loading reduced the amount of time required to ship the given quantity of fuel by roughly thirty percent compared to the uniform loading. The average dose rate to the transportation workers and the public due to the implementation of dual zone loading increased. Implications of these increases are discussed. (authors)

  1. Method for continuously recovering metals using a dual zone chemical reactor

    DOE Patents [OSTI]

    Bronson, M.C.

    1995-02-14

    A dual zone chemical reactor continuously processes metal-containing materials while regenerating and circulating a liquid carrier. The starting materials are fed into a first reaction zone of a vessel containing a molten salt carrier. The starting materials react to form a metal product and a by-product that dissolves in the molten salt that flows to a second reaction zone in the reaction vessel. The second reaction zone is partitioned from, but in fluid communication with, the first reaction zone. The liquid carrier continuously circulates along a pathway between the first reaction zone and the second reaction zone. A reactive gas is introduced into the second reaction zone to react with the reaction by-product to generate the molten salt. The metal product, the gaseous waste products, and the excess liquid carrier are removed without interrupting the operation of the reactor. The design of the dual zone reactor can be adapted to combine a plurality of liquid carrier regeneration zones in a multiple dual zone chemical reactor for production scale processing. 6 figs.

  2. Fidelity of a Time-Resolved Imaging Diagnostic for Electron Beam Profiles

    SciTech Connect (OSTI)

    Frayer, Daniel; Ekdahl, Carl A.; Johnson, Douglas

    2014-10-01

    An optical tomographic diagnostic instrument has been fielded at the Dual-Axis Radiographic Hydrodynamic Test Facility at Los Alamos National Laboratory. Four optical lines of sight create projections of an image of an electron beam on a Cerenkov target, which are relayed via optical fiber to streak cameras. From these projections, a reconstruction algorithm creates time histories of the beams cross section. The instrument was fielded during and after facility commissioning, and tomographic reconstructions reported beam parameters. Results from reconstructions and analysis are noted.

  3. WE-E-BRE-04: Dual Focal Spot Dose Painting for Precision Preclinical Radiobiological Investigations

    SciTech Connect (OSTI)

    Stewart, J; Lindsay, P; Jaffray, D

    2014-06-15

    Purpose: Recent progress in small animal radiotherapy systems has provided the foundation for delivering the heterogeneous, millimeter scale dose distributions demanded by preclinical radiobiology investigations. Despite advances in preclinical dose planning, delivery of highly heterogeneous dose distributions is constrained by the fixed collimation systems and large x-ray focal spot common in small animal radiotherapy systems. This work proposes a dual focal spot dose optimization and delivery method with a large x-ray focal spot used to deliver homogeneous dose regions and a small focal spot to paint spatially heterogeneous dose regions. Methods: Two-dimensional dose kernels were measured for a 1 mm circular collimator with radiochromic film at 10 mm depth in a solid water phantom for the small and large x-ray focal spots on a recently developed small animal microirradiator. These kernels were used in an optimization framework which segmented a desired dose distribution into low- and high-spatial frequency regions for delivery by the large and small focal spot, respectively. For each region, the method determined an optimal set of stage positions and beam-on times. The method was demonstrated by optimizing a bullseye pattern consisting of 0.75 mm radius circular target and 0.5 and 1.0 mm wide rings alternating between 0 and 2 Gy. Results: Compared to a large focal spot technique, the dual focal spot technique improved the optimized dose distribution: 69.2% of the optimized dose was within 0.5 Gy of the intended dose for the large focal spot, compared to 80.6% for the dual focal spot method. The dual focal spot design required 14.0 minutes of optimization, and will require 178.3 minutes for automated delivery. Conclusion: The dual focal spot optimization and delivery framework is a novel option for delivering conformal and heterogeneous dose distributions at the preclinical level and provides a new experimental option for unique radiobiological investigations

  4. Magnetic rotation (MR) band crossing in N=78 odd-Z nuclei: Tilted axis cranking (TAC) calculations to explore the role of nucleons

    SciTech Connect (OSTI)

    Kumar, Suresh

    2014-08-14

    Magnetic Rotation (MR) band crossing is studied systematically in N=78 isotones (La, Pr, Pm and Eu) using Tilted Axis Cranking (TAC) model. The observables such as I(h) vs h?, excitation energy E(MeV) vs spin I(h), and the B(M1)/B(E2) vs I(h) were considered to pinpoint MR crossing in these nuclei. The results of tilted axis cranking were compared with these experimental observables. The B(M1) and B(E2) values were also reported and used to understand the crossing behaviour of these MR bands. The systematic evolution of this phenomenon in N=78 odd-Z istotones leads to understand the role of nucleons in MR band crossing.

  5. Magnetization reversal induced by in-plane current in Ta/CoFeB/MgO structures with perpendicular magnetic easy axis

    SciTech Connect (OSTI)

    Zhang, C.; Yamanouchi, M. Ikeda, S.; Sato, H.; Fukami, S.; Matsukura, F.; Ohno, H.

    2014-05-07

    We investigate in-plane current-induced magnetization reversal under an in-plane magnetic field in Hall bar shaped devices composed of Ta/CoFeB/MgO structures with perpendicular magnetic easy axis. The observed relationship between the directions of current and magnetization switching and Ta thickness dependence of magnetization switching current are accordance with those for magnetization reversal by spin transfer torque originated from the spin Hall effect in the Ta layer.

  6. Influence of compensator thickness, field size, and off-axis distance on the effective attenuation coefficient of a cerrobend compensator for intensity-modulated radiation therapy

    SciTech Connect (OSTI)

    Haghparast, Abbas; Hashemi, Bijan; Eivazi, Mohammad Taghi

    2013-04-01

    Intensity-modulated radiation therapy (IMRT) can be performed by using compensators. To make a compensator for an IMRT practice, it is required to calculate the effective attenuation coefficient (?{sub eff}) of its material, which is affected by various factors. We studied the effect of the variation of the most important factors on the calculation of the ?{sub eff} of the cerrobend compensator for 6-MV photon beams, including the field size, compensator thickness, and off-axis distance. Experimental measurements were carried out at 100 cm source-to-surface distance and 10 cm depth for the 6-MV photon beams of an Elekta linac using various field size, compensator thickness, and off-axis settings. The field sizes investigated ranged from 4 4 to 25 25 cm{sup 2} and the cerrobend compensator thicknesses from 0.56 cm. For a fixed compensator thickness, variation of the ?{sub eff} with the field size ranged from 3.76.8%, with the highest value attributed to the largest compensator thickness. At the reference field size of 10 10 cm{sup 2}, the ?{sub eff} varied by 16.5% when the compensator thickness was increased from 0.56 cm. However, the variation of the ?{sub eff} with the off-axis distance was only 0.99% at this field size, whereas for the largest field size, it was more significant. Our results indicated that the compensator thickness and field size have the most significant effect on the calculation of the compensator ?{sub eff} for the 6-MV photon beam. Therefore, it is recommended to consider these parameters when calculating the compensator thickness for an IMRT practice designed for these beams. The off-axis distance had a significant effect on the calculation of the ?{sub eff} only for the largest field size. Hence, it is recommended to consider the effect of this parameter only for field sizes larger than 25 25 cm{sup 2}.

  7. Charge-screening role of c-axis atomic displacements in YBa2Cu3O6+x and related superconductors

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    E. S. Bozin; Huq, A.; Shen, Bing; Claus, H.; Kwok, W. K.; Tranquada, J. M.

    2016-02-29

    Here, the importance of charge reservoir layers for supplying holes to the CuO2 planes of cuprate superconductors has long been recognized. Less attention has been paid to the screening of the charge transfer by the intervening ionic layers. We address this issue in the case of YBa2Cu3O6+x, where CuO chains supply the holes for the planes. We present a simple dielectric-screening model that gives a linear correlation between the relative displacements of ions along the c axis, determined by neutron powder diffraction, and the hole density of the planes. Applying this model to the temperature-dependent shifts of ions along themore » c axis, we infer a charge transfer of 5–10% of the hole density from the planes to the chains on warming from the superconducting transition to room temperature. Given the significant coupling of c-axis displacements to the average charge density, we point out the relevance of local displacements for screening charge modulations and note recent evidence for dynamic screening of in-plane quasiparticles. This line of argument leads us to a simple model for atomic displacements and charge modulation that is consistent with images from scanning-tunneling microscopy for underdoped Bi2Sr2CaCu2O8+δ.« less

  8. Where does streamwater come from in low-relief forested watersheds? A dual-isotope approach

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Klaus, J.; McDonnell, J. J.; Jackson, C. R.; Du, E.; Griffiths, N. A.

    2015-01-08

    The time and geographic sources of streamwater in low-relief watersheds are poorly understood. This is partly due to the difficult combination of low runoff coefficients and often damped streamwater isotopic signals precluding traditional hydrograph separation and convolution integral approaches. Here we present a dual-isotope approach involving 18O and 2H of water in a low-angle forested watershed to determine streamwater source components and then build a conceptual model of streamflow generation. We focus on three headwater lowland sub-catchments draining the Savannah River Site in South Carolina, USA. Our results for a 3-year sampling period show that the slopes of the meteoricmore » water lines/evaporation water lines (MWLs/EWLs) of the catchment water sources can be used to extract information on runoff sources in ways not considered before. Our dual-isotope approach was able to identify unique hillslope, riparian and deep groundwater, and streamflow compositions. Thus, the streams showed strong evaporative enrichment compared to the local meteoric water line (δ2H = 7.15 · δ18O +9.28‰) with slopes of 2.52, 2.84, and 2.86. Based on the unique and unambiguous slopes of the EWLs of the different water cycle components and the isotopic time series of the individual components, we were able to show how the riparian zone controls baseflow in this system and how the riparian zone "resets" the stable isotope composition of the observed streams in our low-angle, forested watersheds. Although this approach is limited in terms of quantifying mixing percentages between different end-members, our dual-isotope approach enabled the extraction of hydrologically useful information in a region with little change in individual isotope time series.« less

  9. The algebra of dual -1 Hahn polynomials and the Clebsch-Gordan problem of sl{sub -1}(2)

    SciTech Connect (OSTI)

    Genest, Vincent X.; Vinet, Luc; Zhedanov, Alexei

    2013-02-15

    The algebra H of the dual -1 Hahn polynomials is derived and shown to arise in the Clebsch-Gordan problem of sl{sub -1}(2). The dual -1 Hahn polynomials are the bispectral polynomials of a discrete argument obtained from the q{yields}-1 limit of the dual q-Hahn polynomials. The Hopf algebra sl{sub -1}(2) has four generators including an involution, it is also a q{yields}-1 limit of the quantum algebra sl{sub q}(2) and furthermore, the dynamical algebra of the parabose oscillator. The algebra H, a two-parameter generalization of u(2) with an involution as additional generator, is first derived from the recurrence relation of the -1 Hahn polynomials. It is then shown that H can be realized in terms of the generators of two added sl{sub -1}(2) algebras, so that the Clebsch-Gordan coefficients of sl{sub -1}(2) are dual -1 Hahn polynomials. An irreducible representation of H involving five-diagonal matrices and connected to the difference equation of the dual -1 Hahn polynomials is constructed.

  10. NREL, CSEM Jointly Set New Efficiency Record with Dual-Junction Solar Cell

    SciTech Connect (OSTI)

    2016-01-01

    Scientists set a new world record for converting non-concentrated sunlight into electricity using a dual-junction III-V/Si solar cell. National Renewable Energy Laboratory (NREL) and Swiss Center for Electronics and Microtechnology (CSEM) scientists have collaborated to create a novel tandem solar cell that operates at 29.8% conversion efficiency under non-concentrator (1-sun) conditions. In comparison, the 1-sun efficiency of a silicon (Si) single-junction solar cell is probably still a few years away from converging on its practical limit of about 26%.

  11. Integration of progressive hedging and dual decomposition in stochastic integer programs

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Watson, Jean -Paul; Guo, Ge; Hackebeil, Gabriel; Ryan, Sarah M.; Woodruff, David L.

    2015-04-07

    We present a method for integrating the Progressive Hedging (PH) algorithm and the Dual Decomposition (DD) algorithm of Carøe and Schultz for stochastic mixed-integer programs. Based on the correspondence between lower bounds obtained with PH and DD, a method to transform weights from PH to Lagrange multipliers in DD is found. Fast progress in early iterations of PH speeds up convergence of DD to an exact solution. As a result, we report computational results on server location and unit commitment instances.

  12. Note: A novel dual-channel time-of-flight mass spectrometer for photoelectron imaging spectroscopy

    SciTech Connect (OSTI)

    Qin Zhengbo; Wu Xia; Tang Zichao [State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)

    2013-06-15

    A novel dual-channel time-of-flight mass spectrometer (D-TOFMS) has been designed to select anions in the photoelectron imaging measurements. In this instrument, the radiation laser can be triggered precisely to overlap with the selected ion cloud at the first-order space focusing plane. Compared with that of the conventional single channel TOFMS, the in situ mass selection performance of D-TOFMS is significantly improved. Preliminary experiment results are presented for the mass-selected photodetachment spectrum of F{sup -} to demonstrate the capability of the instrument.

  13. Efficacy of fixed filtration for rapid kVp-switching dual energy x-ray systems

    SciTech Connect (OSTI)

    Yao, Yuan; Wang, Adam S.; Pelc, Norbert J.; Department of Radiology, Stanford University, Stanford, California 94305; Department of Electrical Engineering, Stanford University, Stanford, California 94305

    2014-03-15

    Purpose: Dose efficiency of dual kVp imaging can be improved if the two beams are filtered to remove photons in the common part of their spectra, thereby increasing spectral separation. While there are a number of advantages to rapid kVp-switching for dual energy, it may not be feasible to have two different filters for the two spectra. Therefore, the authors are interested in whether a fixed added filter can improve the dose efficiency of kVp-switching dual energy x-ray systems. Methods: The authors hypothesized that a K-edge filter would provide the energy selectivity needed to remove overlap of the spectra and hence increase the precision of material separation at constant dose. Preliminary simulations were done using calcium and water basis materials and 80 and 140 kVp x-ray spectra. Precision of the decomposition was evaluated based on the propagation of the Poisson noise through the decomposition function. Considering availability and cost, the authors chose a commercial Gd{sub 2}O{sub 2}S screen as the filter for their experimental validation. Experiments were conducted on a table-top system using a phantom with various thicknesses of acrylic and copper and 70 and 125 kVp x-ray spectra. The authors kept the phantom exposure roughly constant with and without filtration by adjusting the tube current. The filtered and unfiltered raw data of both low and high energy were decomposed into basis material and the variance of the decomposition for each thickness pair was calculated. To evaluate the filtration performance, the authors measured the ratio of material decomposition variance with and without filtration. Results: Simulation results show that the ideal filter material depends on the object composition and thickness, and ranges across the lanthanide series, with higher atomic number filters being preferred for more attenuating objects. Variance reduction increases with filter thickness, and substantial reductions (40%) can be achieved with a 2 loss in

  14. Light-splitting photovoltaic system utilizing two dual-junction solar cells

    SciTech Connect (OSTI)

    Xiong, Kanglin; Yang, Hui; Lu, Shulong; Dong, Jianrong; Zhou, Taofei; Wang, Rongxin; Jiang, Desheng

    2010-12-15

    There are many difficulties limiting the further development of monolithic multi-junction solar cells, such as the growth of lattice-mismatched material and the current matching constraint. As an alternative approach, the light-splitting photovoltaic system is investigated intensively in different aspects, including the energy loss mechanism and the choice of energy bandgaps of solar cells. Based on the investigation, a two-dual junction system has been implemented employing lattice-matched GaInP/GaAs and InGaAsP/InGaAs cells grown epitaxially on GaAs and InP substrates, respectively. (author)

  15. High strength, low carbon, dual phase steel rods and wires and process for making same

    DOE Patents [OSTI]

    Thomas, Gareth; Nakagawa, Alvin H.

    1986-01-01

    A high strength, high ductility, low carbon, dual phase steel wire, bar or rod and process for making the same is provided. The steel wire, bar or rod is produced by cold drawing to the desired diameter in a single multipass operation a low carbon steel composition characterized by a duplex microstructure consisting essentially of a strong second phase dispersed in a soft ferrite matrix with a microstructure and morphology having sufficient cold formability to allow reductions in cross-sectional area of up to about 99.9%. Tensile strengths of at least 120 ksi to over 400 ksi may be obtained.

  16. Dual-mode self-validating resistance/Johnson noise thermometer system

    DOE Patents [OSTI]

    Shepard, Robert L.; Blalock, Theron V.; Roberts, Michael J.

    1993-01-01

    A dual-mode Johnson noise and DC resistance thermometer capable of use in control systems where prompt indications of temperature changes and long term accuracy are needed. A resistance-inductance-capacitance (RLC) tuned circuit produces a continuous voltage signal for Johnson noise temperature measurement. The RLC circuit provides a mean-squared noise voltage that depends only on the capacitance used and the temperature of the sensor. The sensor has four leads for simultaneous coupling to a noise signal processor and to a DC resistance signal processor.

  17. Dual Selectivity Expressed in [2+2+1] Dynamic Clipping of Unsymmetrical [2]Catenanes

    SciTech Connect (OSTI)

    Liu, Yi

    2010-06-11

    A {pi}-templated dynamic [2+2+1] clipping protocol is established for the synthesis of [2]catenanes from two parts dialdehyde, two parts diamine and one part tetracationic cyclophane. It is further diversified for the selective formation of an unsymmetrical [2]catenane showing great translational selectivity by employing two different dialdehydes in a one-pot reaction. The dual selectivity and the dynamic nature are verified by {sup 1}H NMR spectroscopy, X-ray single crystal structural studies and exchange experiments.

  18. Nitrogen-sensitized dual phase titanate/titania for visible-light driven phenol degradation

    SciTech Connect (OSTI)

    Cheng, Yu Hua; Subramaniam, Vishnu P.; Gong, Dangguo; Tang, Yuxin; Highfield, James; Pehkonen, Simo O.; Pichat, Pierre; Chen, Zhong

    2012-12-15

    A dual-phase material (DP-160) comprising hydrated titanate (H{sub 2}Ti{sub 3}O{sub 7}{center_dot}xH{sub 2}O) and anatase (TiO{sub 2}) was synthesized in a low-temperature one-pot process in the presence of triethylamine (TEA) as the N-source. The unique structure exhibits strong visible light absorption. The chromophore is linked to Ti-N bonds derived from both surface sensitization and sub-surface (bulk) doping. From transmission electron microscope (TEM) and textural studies by N{sub 2} physisorption, the composite exists as mesoporous particles with a grain size of {approx}20 nm and mean pore diameter of 3.5 nm, responsible for the high surface area ({approx}180 m{sup 2}/g). DP-160 demonstrated photocatalytic activity in the degradation of phenol under visible light ({lambda}>420 nm). The activity of the composite was further enhanced by a small addition (0.001 M) of H{sub 2}O{sub 2}, which also gave rise to some visible light activity in the control samples. This effect is believed to be associated with the surface peroxo-titanate complex. GC-MS analyses showed that the intermediate products of phenol degradation induced by visible light irradiation of DP-160 did not differ from those obtained by UV (band-gap) irradiation of TiO{sub 2}. The overall performance of the composite is attributed to efficient excitation via inter-band states (due to N-doping), surface sensitization, improved adsorptive properties of aromatic compounds due to the N-carbonaceous overlayer, and the presence of heterojunctions that are known to promote directional charge transfer in other mixed-phase titanias like Degussa P25. - graphical abstract: Nitrogen-sensitized dual phase titanate/titania photocatalyst showing extended visible light absorption and efficient photocatalytic degradation of phenol. Highlights: Black-Right-Pointing-Pointer Low temperature one-pot synthesis of visible light active dual phase photocatalyst. Black-Right-Pointing-Pointer The dual phase consists of

  19. Dual-etalon cavity ring-down frequency-comb spectroscopy with broad band light source

    DOE Patents [OSTI]

    Chandler, David W; Strecker, Kevin E

    2014-04-01

    In an embodiment, a dual-etalon cavity-ring-down frequency-comb spectrometer system is described. A broad band light source is split into two beams. One beam travels through a first etalon and a sample under test, while the other beam travels through a second etalon, and the two beams are recombined onto a single detector. If the free spectral ranges ("FSR") of the two etalons are not identical, the interference pattern at the detector will consist of a series of beat frequencies. By monitoring these beat frequencies, optical frequencies where light is absorbed may be determined.

  20. Final Technical Report - Integrated Hydrogeophysical and Hydrogeologic Driven Parameter Upscaling for Dual-Domain Transport Modeling

    SciTech Connect (OSTI)

    Shafer, John M

    2012-11-05

    The three major components of this research were: 1. Application of minimally invasive, cost effective hydrogeophysical techniques (surface and borehole), to generate fine scale (~1m or less) 3D estimates of subsurface heterogeneity. Heterogeneity is defined as spatial variability in hydraulic conductivity and/or hydrolithologic zones. 2. Integration of the fine scale characterization of hydrogeologic parameters with the hydrogeologic facies to upscale the finer scale assessment of heterogeneity to field scale. 3. Determination of the relationship between dual-domain parameters and practical characterization data.

  1. Dual-frequency terahertz emission from splitting filaments induced by lens tilting in air

    SciTech Connect (OSTI)

    Zhang, Zhelin; Chen, Yanping Yang, Liu; Yuan, Xiaohui; Liu, Feng; Chen, Min; Xu, Jianqiu; Zhang, Jie; Sheng, Zhengming

    2014-09-08

    Dual-frequency terahertz radiation from air-plasma filaments produced with two-color lasers in air has been demonstrated experimentally. When a focusing lens is tilted for a few degrees, it is shown that the laser filament evolves from a single one to two sub-filaments. Two independent terahertz sources emitted from the sub-filaments with different frequencies and polarizations are identified, where the frequency of terahertz waves from the trailing sub-filament is higher than that from the leading sub-filament.

  2. Dual initiation strip charge apparatus and methods for making and implementing the same

    DOE Patents [OSTI]

    Jakaboski, Juan-Carlos; Todd,; Steven N.; Polisar, Stephen; Hughs, Chance

    2011-03-22

    A Dual Initiation Strip Charge (DISC) apparatus is initiated by a single initiation source and detonates a strip of explosive charge at two separate contacts. The reflection of explosively induced stresses meet and create a fracture and breach a target along a generally single fracture contour and produce generally fragment-free scattering and no spallation. Methods for making and implementing a DISC apparatus provide numerous advantages over previous methods of creating explosive charges by utilizing steps for rapid prototyping; by implementing efficient steps and designs for metering consistent, repeatable, and controlled amount of high explosive; and by utilizing readily available materials.

  3. Process for whole cell saccharification of lignocelluloses to sugars using a dual bioreactor system

    DOE Patents [OSTI]

    Lu, Jue; Okeke, Benedict

    2012-03-27

    The present invention describes a process for saccharification of lignocelluloses to sugars using whole microbial cells, which are enriched from cultures inoculated with paper mill waste water, wood processing waste and soil. A three-member bacterial consortium is selected as a potent microbial inocula and immobilized on inedible plant fibers for biomass saccharification. The present invention further relates the design of a dual bioreactor system, with various biocarriers for enzyme immobilization and repeated use. Sugars are continuously removed eliminating end-product inhibition and consumption by cell.

  4. An advanced economizer controller for dual-duct air-handling systems -- with a case application

    SciTech Connect (OSTI)

    Liu, M.; Claridge, D.E.; Park, B.Y.

    1997-12-31

    A heating penalty is expected when economizers are applied to dual-duct air-handling systems. The heating penalty can be even higher than the cooling savings when the hot airflow is higher than the cold airflow. To avoid the excessive heating penalty, advanced economizers are developed in this paper. The application of the advanced economizer has resulted in savings of $7,000/yr in one 95,000-ft{sup 2} (8,800-m{sup 2}) school building since 1993. The impacts of cold and hot deck settings on the energy consumption are also discussed.

  5. Spectroscopy diagnostic of dual-frequency capacitively coupled CHF{sub 3}/Ar plasma

    SciTech Connect (OSTI)

    Liu, Wen-Yao; Du, Yong-Quan [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China)] [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China); Liu, Yong-Xin; Liu, Jia; Zhao, Tian-Liang; Wang, You-Nian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Xu, Yong; Li, Xiao-Song; Zhu, Ai-Min [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China) [Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 116024 (China); School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-11-15

    A combined spectroscopic method of absorption, actinometry, and relative optical emission intensity is employed to determine the absolute CF{sub 2} density, the relative F and H densities, H atom excitation temperature and the electron density in dual-frequency (60/2 MHz) capacitively coupled CHF{sub 3}/Ar plasmas. The effects of different control parameters, such as high-frequency (HF) power, low-frequency (LF) power, gas pressure, gap length and content of CHF{sub 3}, on the concentration of radical CF{sub 2}, F, and H and excitation temperature are discussed, respectively. It is found that the concentration of CF{sub 2} is strongly dependent on the HF power, operating pressure and the proportion of CHF{sub 3} in feed gas, while it is almost independent of the LF power and the gap length. A higher concentration ratio of F to CF{sub 2} could be obtained in dual-frequency discharge case. Finally, the generation and decay mechanisms of CF{sub 2} and F were also discussed.

  6. Welding Induced Alignment Distortion in Dual-in-Line LD Packages

    SciTech Connect (OSTI)

    Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.; Shi, Frank G.

    2007-11-11

    The tolerance for the movement of a single mode fiber relative to the laser is extremely tight, a submicron movement can often lead to a significant misalignment and thus the reduction in the power coupled into the fiber. Among various fiber pigtailing assembly technologies, pulsed laser welding is the method with submicron accuracy and is most conducive to automation. However, the melting-solidification process during laser welding can often distort the pre-achieved fiber-optic alignment. This Welding-Induced-Alignment-Distortion (WIAD) is a serious concern and significantly affects the yield for single mode fiber pigtailing to a semiconductor laser. In this paper, effect of laser welding sequence on WIAD in a dual-in-line packager is numerically investigated by means of Finite Element Method (FEM). Optimal welding sequence may minimize WIAD in dual-in-line package. Additionally, unsymmetrical space between fiber and U-channel induced by laser welding of U-channelto-plate in DIP LD packages is found to have obvious effect on WIAD.

  7. Microstructure evolution and mechanical behavior of a high strength dual-phase steel under monotonic loading

    SciTech Connect (OSTI)

    Nesterova, E.V.; Bouvier, S.; Bacroix, B.

    2015-02-15

    Transmission electron microscopy (TEM) microstructures of a high-strength dual-phase steel DP800 have been examined after moderate plastic deformations in simple shear and uniaxial tension. Special attention has been paid to the effect of the intergranular hard phase (martensite) on the microstructure evolution in the near-grain boundary regions. Quantitative parameters of dislocation patterning have been determined and compared with the similar characteristics of previously examined single-phase steels. The dislocation patterning in the interiors of the ferrite grains in DP800 steel is found to be similar to that already observed in the single-phase IF (Interstitial Free) steel whereas the martensite-affected zones present a delay in patterning and display very high gradients of continuous (gradual) disorientations associated with local internal stresses. The above stresses are shown to control the work-hardening of dual-phase materials at moderate strains for monotonic loading and are assumed to influence their microstructure evolution and mechanical behavior under strain-path changes. - Highlights: • The microstructure evolution has been studied by TEM in a DP800 steel. • It is influenced by both martensite and dislocations in the initial state. • The DP800 steel presents a high work-hardening rate due to internal stresses.

  8. Temperature dependent dual hydrogen sensor response of Pd nanoparticle decorated Al doped ZnO surfaces

    SciTech Connect (OSTI)

    Gupta, D.; Barman, P. B.; Hazra, S. K.; Dutta, D.; Kumar, M.; Som, T.

    2015-10-28

    Sputter deposited Al doped ZnO (AZO) thin films exhibit a dual hydrogen sensing response in the temperature range 40 °C–150 °C after surface modifications with palladium nanoparticles. The unmodified AZO films showed no response in hydrogen in the temperature range 40 °C–150 °C. The operational temperature windows on the low and high temperature sides have been estimated by isolating the semiconductor-to-metal transition temperature zone of the sensor device. The gas response pattern was modeled by considering various adsorption isotherms, which revealed the dominance of heterogeneous adsorption characteristics. The Arrhenius adsorption barrier showed dual variation with change in hydrogen gas concentration on either side of the semiconductor-to-metal transition. A detailed analysis of the hydrogen gas response pattern by considering the changes in nano palladium due to hydrogen adsorption, and semiconductor-to-metal transition of nanocrystalline Al doped ZnO layer due to temperature, along with material characterization studies by glancing incidence X-ray diffraction, atomic force microscopy, and transmission electron microscopy, are presented.

  9. Turbine-scale wind field measurements using dual-Doppler lidar

    SciTech Connect (OSTI)

    Newsom, Rob K.; Berg, Larry K.; Shaw, William J.; Fischer, Marc

    2015-02-01

    Spatially resolved measurements of micro-scale winds are retrieved using scanning dual-Doppler lidar, and validated against independent in situ wind measurements. Data for this study were obtained during a month-long field campaign conducted at a site in north-central Oklahoma in November of 2010. Observational platforms include one heavily instrumented 60-m meteorological tower and two scanning coherent Doppler lidars. The lidars were configured to perform coordinated dual-Doppler scans surrounding the 60-m tower, and the resulting radial velocity observations were processed to retrieve the 3-component velocity vector field on surfaces defined by the intersecting scan planes. Raw radial velocity measurements from the lidars were calibrated by direct comparison to a sonic anemometer located at the 60 m level on the tower. Wind retrievals were performed using both calibrated and uncalibrated measurements, and validated against the 60-m sonic anemometer observations. Retrievals using uncalibrated radial velocity data show a significant slow bias in the wind speed of about 14%; whereas the retrievals using the calibrated data show a much smaller slow bias of 1.2%. Retrievals using either the calibrated or uncalibrated data exhibit negligible bias in the wind direction (<0.2o), and excellent correlation in the wind speeds (>0.96).

  10. Recognition of chromatin by the plant alkaloid, ellipticine as a dual binder

    SciTech Connect (OSTI)

    Banerjee, Amrita; Sanyal, Sulagna; Majumder, Parijat; Chakraborty, Payal; Jana, Kuladip; Dasgupta, Dipak

    2015-07-10

    Recognition of core histone components of chromatin along with chromosomal DNA by a class of small molecule modulators is worth examining to evaluate their intracellular mode of action. A plant alkaloid ellipticine (ELP) which is a putative anticancer agent has so far been reported to function via DNA intercalation, association with topoisomerase II and binding to telomere region. However, its effect upon the potential intracellular target, chromatin is hitherto unreported. Here we have characterized the biomolecular recognition between ELP and different hierarchical levels of chromatin. The significant result is that in addition to DNA, it binds to core histone(s) and can be categorized as a ‘dual binder’. As a sequel to binding with histone(s) and core octamer, it alters post-translational histone acetylation marks. We have further demonstrated that it has the potential to modulate gene expression thereby regulating several key biological processes such as nuclear organization, transcription, translation and histone modifications. - Highlights: • Ellipticine acts a dual binder binding to both DNA and core histone(s). • It induces structural perturbations in chromatin, chromatosome and histone octamer. • It alters histones acetylation and affects global gene expression.

  11. Visible light stimulating dual-wavelength emission and O vacancy involved energy transfer behavior in luminescence for coaxial nanocable arrays

    SciTech Connect (OSTI)

    Yang, Lei, E-mail: nanoyang@qq.com [College of Materials Science and Engineering, Hunan University, Changsha 410082 (China); Hunan Province Key Laboratory for Spray Deposition Technology and Application, Hunan University, Changsha 410082 (China); Dong, Jiazhang; Jiang, Zhongcheng [College of Materials Science and Engineering, Hunan University, Changsha 410082 (China); Pan, Anlian; Zhuang, Xiujuan [Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan University, Changsha 410082 (China)

    2014-06-14

    We report a strategy to investigate O vacancy (V{sub O}) involved energy transfer and dual-wavelength yellow emission in coaxial nanocable. By electric field deposition and subsequent sol-gel template approach, ZnO:Tb/Y{sub 2}O{sub 3}:Eu coaxial nanocable arrays are synthesized. After visible light excitation, system is promoted to O vacancy charge transfer state of V{sub O}(0/+). In the following cross relaxation, energy transfer from V{sub O} to the excitation energy level of Tb{sup 3+} in ZnO:Tb core area. While in Y{sub 2}O{sub 3}:Eu shell area, energy transfer to the excitation energy level of Eu{sup 3+}. Subsequently, dual-wavelength emission is observed. By constructing nanocable with dual-wavelength emission, yellow luminescence is obtained. Adjust doping concentration of Eu{sup 3+} or Tb{sup 3+} in the range of 0.010.05, chromaticity coordinates of ZnO:Tb/Y{sub 2}O{sub 3}:Eu nanocable stably stays at yellow region in color space except ZnO:Tb{sub 0.01}/Y{sub 2}O{sub 3}:Eu{sub 0.01}. As Vo states act as media in energy transfer process in nanocablers, visible light can stimulate dual-wavelength emissions. Yellow luminescent nanocable arrays will have great applications in light-emitting diode luminescence.

  12. Highly c-axis oriented GaN films grown on free-standing diamond substrates for high-power devices

    SciTech Connect (OSTI)

    Zhang, D. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China) [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024 (China); Bian, J.M., E-mail: jmbian@dlut.edu.cn [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Qin, F.W.; Wang, J.; Pan, L. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China) [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024 (China); Zhao, J.M. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Zhao, Y.; Bai, Y.Z. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China) [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024 (China); Du, G.T. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2011-10-15

    Highlights: {yields} GaN films are deposited on diamond substrates by ECR-PEMOCVD. {yields} Influence of deposition temperature on the properties of samples is investigated. {yields} Properties of GaN films are dependent on the deposition temperature. -- Abstract: GaN films with highly c-axis preferred orientation are deposited on free-standing thick diamond films by low temperature electron cyclotron resonance plasma enhanced metal organic chemical vapor deposition (ECR-PEMOCVD). The TMGa and N{sub 2} are applied as precursors of Ga and N, respectively. The quality of as-grown GaN films are systematically investigated as a function of deposition temperature by means of X-ray diffraction (XRD) analysis, Hall Effect measurement (HL), room temperature photoluminescence (PL) and atomic force microscopy (AFM). The results show that the dense and uniformed GaN films with highly c-axis preferred orientation are successfully achieved on free-standing diamond substrates under optimized deposition temperature of 400 {sup o}C, and the room temperature PL spectra of the optimized GaN film show a intense ultraviolet near band edge emission and a weak yellow luminescence. The obtained GaN/diamond structure has great potential for the development of high-power semiconductor devices due to its excellent heat dissipation nature.

  13. Epitaxial c-axis oriented BaTiO{sub 3} thin films on SrTiO{sub 3}-buffered Si(001) by atomic layer deposition

    SciTech Connect (OSTI)

    Ngo, Thong Q.; McDaniel, Martin D.; Ekerdt, John G., E-mail: ekerdt@che.utexas.edu [Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712 (United States); Posadas, Agham B.; Demkov, Alexander A. [Department of Physics, The University of Texas at Austin, Austin, Texas 78712 (United States); Hu, Chengqing; Yu, Edward T. [Department of Electrical Engineering, The University of Texas at Austin, Austin, Texas 78712 (United States); Bruley, John [IBM Research Division, Yorktown Heights, New York 10593 (United States)

    2014-02-24

    Atomic layer deposition (ALD) of epitaxial c-axis oriented BaTiO{sub 3} (BTO) on Si(001) using a thin (1.6?nm) buffer layer of SrTiO{sub 3} (STO) grown by molecular beam epitaxy is reported. The ALD growth of crystalline BTO films at 225??C used barium bis(triisopropylcyclopentadienyl), titanium tetraisopropoxide, and water as co-reactants. X-ray diffraction (XRD) reveals a high degree of crystallinity and c-axis orientation of as-deposited BTO films. Crystallinity is improved after vacuum annealing at 600??C. Two-dimensional XRD confirms the tetragonal structure and orientation of 720-nm thick films. The effect of the annealing process on the BTO structure is discussed. A clean STO/Si interface is found using in-situ X-ray photoelectron spectroscopy and confirmed by cross-sectional scanning transmission electron microscopy. The capacitance-voltage characteristics of 720?nm-thick BTO films are examined and show an effective dielectric constant of ?660 for the heterostructure.

  14. Note: High-efficiency broadband acoustic energy harvesting using Helmholtz resonator and dual piezoelectric cantilever beams

    SciTech Connect (OSTI)

    Yang, Aichao; Li, Ping Wen, Yumei; Lu, Caijiang; Peng, Xiao; He, Wei; Zhang, Jitao; Wang, Decai; Yang, Feng

    2014-06-15

    A high-efficiency broadband acoustic energy harvester consisting of a compliant-top-plate Helmholtz resonator (HR) and dual piezoelectric cantilever beams is proposed. Due to the high mechanical quality factor of beams and the strong multimode coupling of HR cavity, top plate and beams, the high efficiency in a broad bandwidth is obtained. Experiment exhibits that the proposed harvester at 170–206 Hz has 28–188 times higher efficiency than the conventional harvester using a HR with a piezoelectric composite diaphragm. For input acoustic pressure of 2.0 Pa, the proposed harvester exhibits 0.137–1.43 mW output power corresponding to 0.035–0.36 μW cm{sup −3} volume power density at 170–206 Hz.

  15. Effects of gas pressure on 60/13.56 MHz dual-frequency capacitively coupled plasmas

    SciTech Connect (OSTI)

    Yuan, Q. H.; Yin, G. Q. [Key Laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Xin, Y.; Ning, Z. Y. [School of Physical Science and Technology, Suzhou University, SuZhou 215006 (China)

    2011-05-15

    The electron energy probability functions (EEPFs) were measured with increasing gas pressure in 60/13.56 MHz dual-frequency capacitively coupled plasma (DF-CCP) using compensated Langmiur electrostatic probe. The transition pressure of heating mode from collisionless to collisional heating in 60/13.56 MHz DF-CCP is found to be significantly lower than that in 13.56 MHz single-frequency CCP. As the pressure increases, the EEPFs change from bi-Maxwellian to Druyvesteyn type which is similar with that in 60 MHz single-frequency CCP. The pressure dependence of electron densities, effective electron temperatures, floating potentials, and plasma potentials in 60/13.56 MHz DF-CCP were measured and were compared with that in 60 MHz single-frequency CCP. The pressure dependence of these plasma parameters in 60/13.56 MHz DF-CCP is similar with that in 60 MHz single-frequency CCP.

  16. Dual annular rotating [open quotes]windowed[close quotes] nuclear reflector reactor control system

    DOE Patents [OSTI]

    Jacox, M.G.; Drexler, R.L.; Hunt, R.N.M.; Lake, J.A.

    1994-03-29

    A nuclear reactor control system is provided in a nuclear reactor having a core operating in the fast neutron energy spectrum where criticality control is achieved by neutron leakage. The control system includes dual annular, rotatable reflector rings. There are two reflector rings: an inner reflector ring and an outer reflector ring. The reflectors are concentrically assembled, surround the reactor core, and each reflector ring includes a plurality of openings. The openings in each ring are capable of being aligned or non-aligned with each other. Independent driving means for each of the annular reflector rings is provided so that reactor criticality can be initiated and controlled by rotation of either reflector ring such that the extent of alignment of the openings in each ring controls the reflection of neutrons from the core. 4 figures.

  17. Quasi-phase-matching of the dual-band nonlinear left-handed metamaterial

    SciTech Connect (OSTI)

    Liu, Yahong Song, Kun; Gu, Shuai; Liu, Zhaojun; Guo, Lei; Zhao, Xiaopeng; Zhou, Xin

    2014-11-17

    We demonstrate a type of nonlinear meta-atom creating a dual-band nonlinear left-handed metamaterial (DNLHM). The DNLHM operates at two distinct left-handed frequency bands where there is an interval of one octave between the two center frequencies. Under the illumination of a high-power signal at the first left-handed frequency band corresponding to fundamental frequency (FF), second-harmonic generation (SHG) is observed at the second left-handed band. This means that our DNLHM supports backward-propagating waves both at FF and second-harmonic (SH) frequency. We also experimentally demonstrate quasi-phase-matching configurations for the backward SHG. This fancy parametric process can significantly transmits the SH generated by an incident FF wave.

  18. Dual-sensor technique for characterization of carrier lifetime decay transients in semiconductors

    SciTech Connect (OSTI)

    Ahrenkiel, R. K.; Johnston, S. W.; Kuciauskas, D.; Tynan, Jerry

    2014-12-07

    This work addresses the frequent discrepancy between transient photoconductive (PC) decay and transient photoluminescence (PL) decay. With this dual- sensor technique, one measures the transient PC and PL decay simultaneously with the same incident light pulse, removing injection-level uncertainty. Photoconductive decay measures the transient photoconductivity, Δσ(t). PCD senses carriers released from shallow traps as well as the photo-generated electron-hole pairs. In addition, variations in carrier mobility with injection level (and time) contribute to the decay time. PL decay senses only electron-hole recombination via photon emission. Theory and experiment will show that the time dependence of the two techniques can be quite different at high injection.

  19. Independently tunable dual-band perfect absorber based on graphene at mid-infrared frequencies

    SciTech Connect (OSTI)

    Zhang, Yuping; Li, Tongtong; Chen, Qi; Zhang, Huiyun; O’Hara, John F.; Abele, Ethan; Taylor, Antoinette J.; Chen, Hou-Tong; Azad, Abul K.

    2015-12-22

    We design a dual-band absorber formed by combining two cross-shaped metallic resonators of different sizes within a super-unit-cell arranged in mirror symmetry. Simulations indicate that absorption efficiencies greater than 99% can be achieved at two different frequencies under normal incidence. We also employ a design scheme with graphene integration, which allows independent tuning of individual absorption frequencies by electrostatically changing the Fermi energy of the graphene layer. High absorbance is maintained over a wide incident angle range up to 50 degrees for both TE and TM polarizations. Thus, it enables a promising way to design electrically tunable absorbers, which may contribute toward the realization of frequency selective detectors for sensing applications.

  20. High-throughput, dual probe biological assays based on single molecule detection

    DOE Patents [OSTI]

    Hollars, Christopher W.; Huser, Thomas R.; Lane, Stephen M.; Balhorn, Rodney L.; Bakajin, Olgica; Darrow, Christopher; Satcher, Jr., Joe H.

    2006-07-11

    A method and apparatus with the sensitivity to detect and identify single target molecules through the localization of dual, fluorescently labeled probe molecules. This can be accomplished through specific attachment of the taget to a surface or in a two-dimensional (2D) flowing fluid sheet having approximate dimensions of 0.5 .mu.m.times.100 .mu.m.times.100 .mu.m. A device using these methods would have 10.sup.3 10.sup.4 greater throughput than previous one-dimensional (1D) micro-stream devices having 1 .mu.m.sup.3 interrogation volumes and would for the first time allow immuno- and DNA assays at ultra-low (femtomolar) concentrations to be performed in short time periods (.about.10 minutes). The use of novel labels (such as metal or semiconductor nanoparticles) may be incorporated to further extend the sensitivity possibly into the attomolar range.

  1. Controlled rolling process for dual phase steels and application to rod, wire, sheet and other shapes

    DOE Patents [OSTI]

    Thomas, G.; Ahn, J.H.; Kim, N.J.

    1986-10-28

    An improved, energy efficient, hot rolling method for direct production of cold formable dual-phase steel is provided. The steel is heated to completely austenitize it and then continuously hot rolled and cooled down into the ferrite-austenite two phase region to a temperature which is just below the effective Ar[sub 3] temperature. The hot rolled steel is then rapidly quenched to provide an alloy containing strong, tough lath martensite (fibers) in a ductile soft ferrite matrix. The method is particularly useful for providing rods in which form the alloy is capable of being drawn into high strength wire or the like in a cold drawing operation without any intermediate annealing or patenting, and has excellent strength, ductility and fatigue characteristics. 3 figs.

  2. A Dual Channel X-ray Spectrometer for Fast Ignition Research

    SciTech Connect (OSTI)

    Akli, K U; Patel, P K; Van Maren, R; Stephens, R B; Key, M H; Higginson, D P; Westover, B; Chen, C D; Mackinnon, A J; Bartal, T; Beg, F N; Chawla, S; Fedosejevs, R; Freeman, R R; Hey, D S; Kemp, G E; LePape, S; Link, A; Ma, T; MacPhee, A G; McLean, H S; Ping, Y; Tsui, Y Y; Van Woerkom, L D; Wei, M S; Yabuuchi, T

    2010-04-19

    A new Dual Channel Highly Ordered Pyrolytic Graphite (DC-HOPG) x-ray spectrometer was developed to study laser-generated electron beam transport. The instrument uses a pair of graphite crystals and has the advantage of simultaneously detecting self emission from low-Z materials in first diffraction order and high-Z materials in second order. The emissions from the target are detected using a pair of parallel imaging plates positioned in a such way that the noise from background is minimized and the mosaic focusing is achieved. Initial tests of the diagnostic on Titan laser (I {approx} 10{sup 20} W/cm{sup 2}, {tau} = 0.7 ps) show excellent signal-to-noise ratio (SNR) > 1000 for the low energy channel and SNR > 400 for the high energy channel.

  3. Shock loading characteristics of Zr and Ti metals using dual beam velocimeter

    SciTech Connect (OSTI)

    Saxena, A. K. Kaushik, T. C.; Gupta, Satish C.

    2015-08-21

    The characteristics of titanium and zirconium metal foils under shock loading have been studied up to 16 GPa and 12 GPa pressure, respectively, using portable electric gun setup as projectile launcher. In these experiments, the capabilities of a single Fabry-Perot velocimeter have been enhanced by implementing it in dual beam mode to record the two velocity profiles on a single streak camera. The measured equation of state data for both the metals have been found to be well in agreement with the reported Hugoniot, within experimental accuracies. A phase transition from α to ω phase has been detected near to 11.4 GPa for titanium and 8.2 GPa for zirconium in the rising part of target-glass interface velocity profile.

  4. Spherically symmetric self-dual Yang-Mills instantons on curved backgrounds in all even dimensions

    SciTech Connect (OSTI)

    Radu, Eugen; Tchrakian, D. H.; Yang Yisong

    2008-02-15

    We present several different classes of self-dual Yang-Mills instantons in all even d-dimensional backgrounds with Euclidean signature. In d=4p+2 the only solutions we found are on constant curvature dS (de Sitter) and AdS (anti-de Sitter) backgrounds and are evaluated in closed form. In d=4p an interesting class of instantons are given on black hole backgrounds. One class of solutions are (Euclidean) time-independent and spherically symmetric in d-1 dimensions, and the other class are spherically symmetric in all d dimensions. Some of the solutions in the former class are evaluated numerically, all the rest being given in closed form. Analytic proofs of existence covering all numerically evaluated solutions are given. All instantons studied have finite action and vanishing energy momentum tensor and do not disturb the geometry.

  5. Controlled rolling process for dual phase steels and application to rod, wire, sheet and other shapes

    DOE Patents [OSTI]

    Thomas, Gareth; Ahn, Jae-Hwan; Kim, Nack-Joon

    1986-01-01

    An improved, energy efficient, hot rolling method for direct production of cold formable dual-phase steel is provided. The steel is heated to completely austenitize it and then continuously hot rolled and cooled down into the ferrite-austenite two phase region to a temperature which is just below the effective Ar.sub.3 temperature. The hot rolled steel is then rapidly quenched to provide an alloy containing strong, tough lath martensite (fibers) in a ductile soft ferrite matrix. The method is particularly useful for providing rods in which form the alloy is capable of being drawn into high strength wire or the like in a cold drawing operation without any intermediate annealing or patenting, and has excellent strength, ductility and fatigue characteristics.

  6. Fat to muscle ratio measurements with dual energy x-ray absorbtiometry

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chen, A.; Luo, J.; Wang, A.; Broadbent, C.; Zhong, J.; Dilmanian, F. A.; Zafonte, F.; Zhong, Z.

    2015-03-14

    Accurate measurement of the fat-to-muscle ratio in animal model is important for obesity research. In addition, an efficient way to measure the fat to muscle ratio in animal model using dual-energy absorptiometry is presented in this paper. A radioactive source exciting x-ray fluorescence from a target material is used to provide the two x-ray energies needed. The x-rays, after transmitting through the sample, are measured with an energy-sensitive Ge detector. Phantoms and specimens were measured. The results showed that the method was sensitive to the fat to muscle ratios with good linearity. A standard deviation of a few percent inmore » the fat to muscle ratio could be observed with the x-ray dose of 0.001 mGy.« less

  7. Dual-completion design for HP/HT corrosive oil well, Villafortuna-Trecate Italy

    SciTech Connect (OSTI)

    Cerruti, S.E.

    1994-12-31

    Villafortuna-Trecate (Italy) oil field is one of the deepest hydrocarbon deposit in production with a reservoir pressure over 15 Ksi, bottom hole temperature in the range of 380 F and corrosive environment due the presence of carbon dioxide and hydrogen sulfide in the production fluids. The design of Villafortuna-Trecate completions requested effort in the selection of appropriate equipment and materials that would enhance the safety, longevity and production capacity of the wells. The paper will discuss the dual completion design outlining the supporting logic and concepts together with the equipment innovations utilized. It includes discussion on tubing material and design, tubing connection, wellhead equipment, completion schemes and related equipment, annulus fluid and displacement technique. Quality control aspects are also discussed. It should serve as a general example of conditions unique to deep, high pressure, high temperature corrosive wells and should be of interest to engineers facing a similar task.

  8. Self-latching eccentric cam for dual stroke compressor or pump

    DOE Patents [OSTI]

    Sisk, F.J.

    1985-01-22

    For a dual capacity refrigerant compressor of the type which has an eccentric cam rotatable on a crankpin between two opposite positions which changes the total eccentricity of the crankpin and cam so as to obtain two different stroke lengths, the rotation of the cam on the crankpin being effected by a reversal of motor operation, the cam moves through an angle of about 270[degree] around the crankpin so that a centrifugal force torque tending to hold the cam in place is available at least in the reduced stroke length position of the cam, and by providing lightening cavities and eccentric weightings, the center of mass of the cam can be shifted to obtain the centrifugal torque in the proper direction at both the maximum and reduced stroke positions. 7 figs.

  9. Self-latching eccentric cam for dual stroke compressor or pump

    DOE Patents [OSTI]

    Sisk, Francis J.

    1985-01-01

    For a dual capacity refrigerant compressor of the type which has an eccentric cam rotatable on a crankpin between two opposite positions which changes the total eccentricity of the crankpin and cam so as to obtain two different stroke lengths, the rotation of the cam on the crankpin being effected by a reversal of motor operation, the cam moves through an angle of about 270.degree. around the crankpin so that a centrifugal force torque tending to hold the cam in place is available at least in the reduced stroke length position of the cam, and by providing lightening cavities and eccentric weightings, the center of mass 74 of the cam can be shifted to obtain the centrifugal torque in the proper direction at both the maximum and reduced stroke positions.

  10. Solar Photo Catalytic Hydrogen Production from water using a dual bed photosystem

    SciTech Connect (OSTI)

    Florida Solar Energy Center

    2003-03-30

    A body of work was performed in which the feasibility of photocatalytically decomposing water into its constituent elements using a dual bed, or modular photosystem, under solar radiation was investigated. The system envisioned consists of two modules, each consisting of a shallow, flat, sealed container, in which microscopic photocatalytic particles are immobilized. The photocatalysts absorb light, generating free electrons and lattice vacancy holes, which are capable of performing reductive and oxidative chemistry, respectively. The photocatalysts would be chosen as to whether they specifically promote H{sub 2} or O{sub 2} evolution in their respective containers. An aqueous solution containing a redox mediator is pumped between the two chambers in order to transfer electron equivalents from one reaction to the other.

  11. Enhanced transportation of energetic electrons in dual-frequency atmospheric microplasmas

    SciTech Connect (OSTI)

    Kwon, H. C.; Kim, H. Y.; Won, I. H.; Lee, H. Wk.; Shin, H. K.; Lee, J. K.

    2013-02-15

    A comparative study of electron kinetics between single-frequency (SF) microplasmas and their equivalent dual-frequency (DF) microplasmas with matching effective frequencies in atmospheric-pressure helium discharges was performed using particle-in-cell simulation with a Monte Carlo collision. The effective-frequency concept helps in analyzing DF microplasmas in a fashion similar to SF microplasmas with effective parameters. In this study, the plasma characteristics such as the plasma potential, density, and electron energy probability functions of the SF microplasma and its DF counterpart were almost the same. However, the oscillating sheath edge was pushed further into the electrode for a substantial fraction of the time and the sheath width decreased in DF microplasmas. As a result, the transportation of the energetic electrons ({epsilon} > 4 eV) usable for tailoring the surface chemistry in atmospheric microplasmas is enhanced in DF microplasmas as compared to SF microplasmas.

  12. Independently tunable dual-band perfect absorber based on graphene at mid-infrared frequencies

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Yuping; Li, Tongtong; Chen, Qi; Zhang, Huiyun; O’Hara, John F.; Abele, Ethan; Taylor, Antoinette J.; Chen, Hou-Tong; Azad, Abul K.

    2015-12-22

    We design a dual-band absorber formed by combining two cross-shaped metallic resonators of different sizes within a super-unit-cell arranged in mirror symmetry. Simulations indicate that absorption efficiencies greater than 99% can be achieved at two different frequencies under normal incidence. We also employ a design scheme with graphene integration, which allows independent tuning of individual absorption frequencies by electrostatically changing the Fermi energy of the graphene layer. High absorbance is maintained over a wide incident angle range up to 50 degrees for both TE and TM polarizations. Thus, it enables a promising way to design electrically tunable absorbers, which maymore » contribute toward the realization of frequency selective detectors for sensing applications.« less

  13. Microstructure and properties of pipeline steel with a ferrite/martensite dual-phase microstructure

    SciTech Connect (OSTI)

    Li Rutao Zuo Xiurong Hu Yueyue Wang Zhenwei Hu, Dingxu

    2011-08-15

    In order to satisfy the transportation of the crude oil and gas in severe environmental conditions, a ferrite/martensite dual-phase pipeline steel has been developed. After a forming process and double submerged arc welding, the microstructure of the base metal, heat affected zone and weld metal was characterized using scanning electron microscopy and transmission electron microscopy. The pipe showed good deformability and an excellent combination of high strength and toughness, which is suitable for a pipeline subjected to the progressive and abrupt ground movement. The base metal having a ferrite/martensite dual-phase microstructure exhibited excellent mechanical properties in terms of uniform elongation of 7.5%, yield ratio of 0.78, strain hardening exponent of 0.145, an impact energy of 286 J at - 10 deg. C and a shear area of 98% at 0 deg. C in the drop weight tear test. The tensile strength and impact energy of the weld metal didn't significantly reduce, because of the intragranularly nucleated acicular ferrites microstructure, leading to high strength and toughness in weld metal. The heat affected zone contained complete quenching zone and incomplete quenching zone, which exhibited excellent low temperature toughness of 239 J at - 10 deg. C. - Research Highlights: {yields}The pipe with ferrite/martensite microstructure shows high deformability. {yields}The base metal of the pipe consists of ferrite and martensite. {yields}Heat affected zone shows excellent low temperature toughness. {yields}Weld metal mainly consists of intragranularly nucleated acicular ferrites. {yields}Weld metal shows excellent low temperature toughness and high strength.

  14. Project Title: Radiochemical Analysis by High Sensitivity Dual-Optic Micro X-ray Fluorescence

    SciTech Connect (OSTI)

    Havrilla, George J.; Gao, Ning

    2002-06-01

    A novel dual-optic micro X-ray fluorescence instrument will be developed to do radiochemical analysis of high-level radioactive wastes at DOE sites such as Savannah River Site and Hanford. This concept incorporates new X-ray optical elements such as monolithic polycapillaries and double bent crystals, which focus X-rays. The polycapillary optic can be used to focus X-rays emitted by the X-ray tube thereby increasing the X-ray flux on the sample over 1000 times. Polycapillaries will also be used to collect the X-rays from the excitation site and screen the radiation background from the radioactive species in the specimen. This dual-optic approach significantly reduces the background and increases the analyte signal thereby increasing the sensitivity of the analysis. A doubly bent crystal used as the focusing optic produces focused monochromatic X-ray excitation, which eliminates the bremsstrahlung background from the X-ray source. The coupling of the doubly bent crystal for monochromatic excitation with a polycapillary for signal collection can effectively eliminate the noise background and radiation background from the specimen. The integration of these X-ray optics increases the signal-to-noise and thereby increases the sensitivity of the analysis for low-level analytes. This work will address a key need for radiochemical analysis of high-level waste using a non-destructive, multi-element, and rapid method in a radiation environment. There is significant potential that this instrumentation could be capable of on-line analysis for process waste stream characterization at DOE sites.

  15. A Dual Regime Reactive Transport Model for Simulation of High Level Waste Tank Closure Scenarios - 13375

    SciTech Connect (OSTI)

    Sarkar, Sohini; Kosson, David S.; Brown, Kevin; Garrabrants, Andrew C.; Meeussen, Hans; Van der Sloot, Hans

    2013-07-01

    A numerical simulation framework is presented in this paper for estimating evolution of pH and release of major species from grout within high-level waste tanks after closure. This model was developed as part of the Cementitious Barriers Partnership. The reactive transport model consists of two parts - (1) transport of species, and (2) chemical reactions. The closure grout can be assumed to have varying extents of cracking and composition for performance assessment purposes. The partially or completely degraded grouted tank is idealized as a dual regime system comprising of a mobile region having solid materials with cracks and macro-pores, and an immobile/stagnant region having solid matrix with micropores. The transport profiles of the species are calculated by incorporating advection of species through the mobile region, diffusion of species through the immobile/stagnant region, and exchange of species between the mobile and immobile regions. A geochemical speciation code in conjunction with the pH dependent test data for a grout material is used to obtain a mineral set that best describes the trends in the test data of the major species. The dual regime reactive transport model predictions are compared with the release data from an up-flow column percolation test. The coupled model is then used to assess effects of crack state of the structure, rate and composition of the infiltrating water on the pH evolution at the grout-waste interface. The coupled reactive transport model developed in this work can be used as part of the performance assessment process for evaluating potential risks from leaching of a cracked tank containing elements of human health and environmental concern. (authors)

  16. Merger-driven fueling of active galactic nuclei: Six dual and of AGNs discovered with Chandra and Hubble Space Telescope observations

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Comerford, Julia M.; Pooley, David; Barrows, R. Scott; Greene, Jenny E.; Zakamska, Nadia L.; Madejski, Greg M.; Cooper, Michael C.

    2015-06-19

    Dual active galactic nuclei (AGNs) and offset AGNs are kpc-scale separation supermassive black holes pairs created during galaxy mergers, where both or one of the black holes are AGNs, respectively. These dual and offset AGNs are valuable probes of the link between mergers and AGNs but are challenging to identify. Here we present Chandra/ACIS observations of 12 optically selected dual AGN candidates atmore » $$z\\lt 0.34$$, where we use the X-rays to identify AGNs. We also present Hubble Space Telescope/Wide Field Camera 3 observations of 10 of these candidates, which reveal any stellar bulges accompanying the AGNs. We discover a dual AGN system with separation $${\\rm \\Delta }x=2.2$$ kpc, where the two stellar bulges have coincident [O iii] λ5007 and X-ray sources. This system is an extremely minor merger (460:1) that may include a dwarf galaxy hosting an intermediate mass black hole. We also find six single AGNs, and five systems that are either dual or offset AGNs with separations $${\\rm \\Delta }x\\lt 10$$ kpc. Four of the six dual AGNs and dual/offset AGNs are in ongoing major mergers, and these AGNs are 10 times more luminous, on average, than the single AGNs in our sample. This hints that major mergers may preferentially trigger higher luminosity AGNs. Further, we find that confirmed dual AGNs have hard X-ray luminosities that are half of those of single AGNs at fixed [O III] λ5007 luminosity, on average. Lastly, this could be explained by high densities of gas funneled to galaxy centers during mergers, and emphasizes the need for deeper X-ray observations of dual AGN candidates.« less

  17. TU-F-18A-09: CT Number Stability Across Patient Sizes Using Virtual-Monoenergetic Dual-Energy CT

    SciTech Connect (OSTI)

    Michalak, G; Grimes, J; Fletcher, J; McCollough, C; Halaweish, A

    2014-06-15

    Purpose: Virtual-monoenergetic imaging uses dual-energy CT data to synthesize images corresponding to a single photon energy, thereby reducing beam-hardening artifacts. This work evaluated the ability of a commercial virtual-monoenergetic algorithm to achieve stable CT numbers across patient sizes. Methods: Test objects containing a range of iodine and calcium hydroxyapatite concentrations were placed inside 8 torso-shaped water phantoms, ranging in lateral width from 15 to 50 cm, and scanned on a dual-source CT system (Siemens Somatom Force). Single-energy scans were acquired from 70-150 kV in 10 kV increments; dual-energy scans were acquired using 4 energy pairs (low energy: 70, 80, 90, and 100 kV; high energy: 150 kV + 0.6 mm Sn). CTDIvol was matched for all single- and dual-energy scans for a given phantom size. All scans used 128×0.6 mm collimation and were reconstructed with 1-mm thickness at 0.8-mm increment and a medium smooth body kernel. Monoenergetic images were generated using commercial software (syngo Via Dual Energy, VA30). Iodine contrast was calculated as the difference in mean iodine and water CT numbers from respective regions-of-interest in 10 consecutive images. Results: CT numbers remained stable as phantom width varied from 15 to 50 cm for all dual-energy data sets (except for at 50 cm using 70/150Sn due to photon starvation effects). Relative to the 15 cm phantom, iodine contrast was within 5.2% of the 70 keV value for phantom sizes up to 45 cm. At 90/150Sn, photon starvation did not occur at 50 cm, and iodine contrast in the 50-cm phantom was within 1.4% of the 15-cm phantom. Conclusion: Monoenergetic imaging, as implemented in the evaluated commercial system, eliminated the variation in CT numbers due to patient size, and may provide more accurate data for quantitative tasks, including radiation therapy treatment planning. Siemens Healthcare.

  18. Investigating the Influence of the Added Mass Effect to Marine Hydrokinetic Horizontal-Axis Turbines Using a General Dynamic Wake Wind Turbine Code: Preprint

    SciTech Connect (OSTI)

    Maniaci, D. C.; Li, Y.

    2012-04-01

    This paper describes a recent study to investigate the applicability of a horizontal-axis wind turbine (HAWT) structural dynamics and unsteady aerodynamics analysis program (FAST and AeroDyn respectively) to modeling the forces on marine hydrokinetic (MHK) turbines. It summarizes the added mass model that has been added to AeroDyn. The added mass model only includes flow acceleration perpendicular to the rotor disc, and ignores added mass forces caused by blade deflection. A model of the National Renewable Energy Laboratory's (NREL) Unsteady Aerodynamics Experiment (UAE) Phase VI wind turbine was analyzed using FAST and AeroDyn with sea water conditions and the new added mass model. The results of this analysis exhibited a 3.6% change in thrust for a rapid pitch case and a slight change in amplitude and phase of thrust for a case with 30 degrees of yaw.

  19. Investigation of the on-axis atom number density in the supersonic gas jet under high gas backing pressure by simulation

    SciTech Connect (OSTI)

    Chen, Guanglong; Xu, Yi; Cao, Yunjiu; Mi, Yiming; Zhang, Xiuli; Wang, Lili; Boldarev, A. S.; Geng, Xiaotao; Kim, Dong Eon

    2015-10-15

    The supersonic gas jets from conical nozzles are simulated using 2D model. The on-axis atom number density in gas jet is investigated in detail by comparing the simulated densities with the idealized densities of straight streamline model in scaling laws. It is found that the density is generally lower than the idealized one and the deviation between them is mainly dependent on the opening angle of conical nozzle, the nozzle length and the gas backing pressure. The density deviation is then used to discuss the deviation of the equivalent diameter of a conical nozzle from the idealized d{sub eq} in scaling laws. The investigation on the lateral expansion of gas jet indicates the lateral expansion could be responsible for the behavior of the density deviation. These results could be useful for the estimation of cluster size and the understanding of experimental results in laser-cluster interaction experiments.

  20. Note: Accuracy of velocity correction for impact of a laser-accelerated miniature flyer with lithium fluoride shock-compressed along the [100] axis

    SciTech Connect (OSTI)

    Wakabayashi, Kunihiko; Matsumura, Tomoharu; Nakayama, Yoshio; Koshi, Mitsuo

    2011-02-15

    We performed miniature flyer impact experiments to investigate the relationship between the apparent (u{sub a}) and actual (u{sub A}) particle velocities measured by a velocity interferometer in single-crystal lithium fluoride (LiF) that was shock-compressed along the [100] axis. The miniature flyer was accelerated to velocities in the range 652.5-1937.6 m/s by a tabletop pulsed laser. An empirical relationship of u{sub a}= (1.2749 {+-} 0.0102)u{sub A} was obtained. The obtained relationship agreed well with the results of a previous study within the experimental errors and its uncertainty was less than {+-}1%. This result indicates that the present experimental technique is effective for measuring the relationship between u{sub a} and u{sub A} of shocked transparent materials with a comparable accuracy to conventional methods.

  1. Towards quantitative off-axis electron holographic mapping of the electric field around the tip of a sharp biased metallic needle

    SciTech Connect (OSTI)

    Beleggia, M.; Kasama, T.; Larson, D. J.; Kelly, T. F.; Dunin-Borkowski, R. E.; Pozzi, G.

    2014-07-14

    We apply off-axis electron holography and Lorentz microscopy in the transmission electron microscope to map the electric field generated by a sharp biased metallic tip. A combination of experimental data and modelling provides quantitative information about the potential and the field around the tip. Close to the tip apex, we measure a maximum field intensity of 82 MV/m, corresponding to a field k factor of 2.5, in excellent agreement with theory. In order to verify the validity of the measurements, we use the inferred charge density distribution in the tip region to generate simulated phase maps and Fresnel (out-of-focus) images for comparison with experimental measurements. While the overall agreement is excellent, the simulations also highlight the presence of an unexpected astigmatic contribution to the intensity in a highly defocused Fresnel image, which is thought to result from the geometry of the applied field.

  2. Investigating the Influence of the Added Mass Effect to Marine Hydrokinetic Horizontal-Axis Turbines Using a General Dynamic Wake Wind Turbine Code

    SciTech Connect (OSTI)

    Maniaci, D. C.; Li, Y.

    2011-10-01

    This paper describes a recent study to investigate the applicability of a horizontal-axis wind turbine (HAWT) structural dynamics and unsteady aerodynamics analysis program (FAST and AeroDyn respectively) to modeling the forces on marine hydrokinetic (MHK) turbines. This paper summarizes the added mass model that has been added to AeroDyn. The added mass model only includes flow acceleration perpendicular to the rotor disc, and ignores added mass forces caused by blade deflection. A model of the National Renewable Energy Laboratory's (NREL) Unsteady Aerodynamics Experiment (UAE) Phase VI wind turbine was analyzed using FAST and AeroDyn with sea water conditions and the new added mass model. The results of this analysis exhibited a 3.6% change in thrust for a rapid pitch case and a slight change in amplitude and phase of thrust for a case with 30{sup o} of yaw.

  3. Combined effects of perfluorooctane sulfonate (PFOS) and maternal restraint stress on hypothalamus adrenal axis (HPA) function in the offspring of mice

    SciTech Connect (OSTI)

    Ribes, Diana; Fuentes, Silvia; Torrente, Margarita; Colomina, M. Teresa [Department of Psychology and Research Center for Behavioral Assessment (CRAMC), 'Rovira i Virgili' University, Sescelades Campus, 43007 Tarragona, Catalonia (Spain); Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, 'Rovira i Virgili' University, Sant Llorenc 21, 43201 Reus, Catalonia (Spain); Domingo, Jose L., E-mail: joseluis.domingo@urv.ca [Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, 'Rovira i Virgili' University, Sant Llorenc 21, 43201 Reus, Catalonia (Spain)

    2010-02-15

    Although it is known that prenatal exposure to perfluorooctane sulfonate (PFOS) can cause developmental adverse effects in mammals, the disruptive effects of this compound on hormonal systems are still controversial. Information concerning the effects of PFOS on hypothalamus adrenal (HPA) axis response to stress and corticosterone levels is not currently available. On the other hand, it is well established that stress can enhance the developmental toxicity of some chemicals. In the present study, we assessed the combined effects of maternal restraint stress and PFOS on HPA axis function in the offspring of mice. Twenty plug-positive female mice were divided in two groups. Animals were given by gavage 0 and 6 mg PFOS/kg/day on gestation days 12-18. One half of the animals in each group were also subjected to restraint stress (30 min/session, 3 sessions/day) during the same period. Five plug-positive females were also included as non-manipulated controls. At 3 months of age, activity in an open-field and the stress response were evaluated in male and female mice by exposing them to 30 min of restraint stress. Male and female offspring were subsequently sacrificed and blood samples were collected to measure changes in corticosterone levels at four different moments related to stress exposure conditions: before stress exposure, immediately after 30 min of stress exposure, and recuperation levels at 60 and 90 min after stress exposure. Results indicate corticosterone levels were lower in mice prenatally exposed to restraint. In general terms, PFOS exposure decreased corticosterone levels, although this effect was only significant in females. The recuperation pattern of corticosterone was mainly affected by prenatal stress. Interactive effects between PFOS and maternal stress were sex dependent. The current results suggest that prenatal PFOS exposure induced long-lasting effects in mice.

  4. Proposal of a gigawatt-class L/Ku dual-band magnetically insulated transmission line oscillator

    SciTech Connect (OSTI)

    Ju, J.-C. Fan, Y.-W.; Shu, T.; Zhong, H.-H.

    2014-10-15

    We present a gigawatt (GW)-class magnetically insulated transmission line oscillator (MILO) which is capable of generating dual-band high power microwaves (HPMs). The proposed device, deriving from previously studied complex MILO and dual-frequency MILO, is designed to produce two HPMs in L-band and Ku-band, respectively. It is found in particle-in-cell (PIC) simulation that when the diode voltage is 610 kV, HPMs with frequencies of 1.72 GHz and 14.6 GHz can be achieved with powers of 3.3 GW and 2.4 GW, respectively. The corresponding total power conversion efficiency is approximately 12.8%. Power difference of the two generated HPMs is approximately 1.4 dB, and frequency difference of them reaches a level as high as ∼10 dB.

  5. An ECT/ERT dual-modality sensor for oil-water two-phase flow measurement

    SciTech Connect (OSTI)

    Wang, Pitao; Wang, Huaxiang; Sun, Benyuan; Cui, Ziqiang; Huang, Wenrui

    2014-04-11

    This paper presents a new sensor for ECT/ERT dual-modality system which can simultaneously obtain the permittivity and conductivity of the materials in the pipeline. Quasi-static electromagnetic fields are produced by the inner electrodes array sensor of electrical capacitance tomography (ECT) system. The results of simulation show that the data of permittivity and conductivity can be simultaneously obtained from the same measurement electrode and the fusion of two kinds of data may improve the quality of the reconstructed images. For uniform oil-water mixtures, the performance of designed dual-modality sensor for measuring the various oil fractions has been tested on representative data and the results of experiments show that the designed sensor broadens the measurement range compared to single modality.

  6. Safety of natural gas dual-fueled vehicles: Addendum to safety analysis of natural gas vehicles transiting highway tunnels

    SciTech Connect (OSTI)

    Shaaban, S.H.; Zalak, V.M. )

    1991-01-01

    A safety analysis was performed to assess the relative hazard of vehicles containing both compressed natural gas (CNG) and gasoline, referred to as dual-fueled vehicles, compared to the hazard of a dedicated CNG vehicle. This study expands upon previous work that examined the safety of CNG vehicles transiting highway tunnels. The approach was to examine operational data, test results and to perform thermal analyses to determine if there are any synergistic effects where the total consequences of fuel release might be greater than the sum of the two fuels released separately. This study concluded that a dual-fueled vehicle poses a slightly greater risk than a dedicated CNG vehicle; however, this marginal increase in risk is small and is within the bounds of risk posed by gasoline-powered vehicles. 4 refs.

  7. Dual-cavity mode converter for a fundamental mode output in an over-moded relativistic backward-wave oscillator

    SciTech Connect (OSTI)

    Li, Jiawei; Huang, Wenhua; Xiao, Renzhen; Bai, Xianchen; Zhang, Yuchuan; Zhang, Xiaowei; Shao, Hao; Chen, Changhua; Zhu, Qi

    2015-03-16

    A dual-cavity TM{sub 02}–TM{sub 01} mode converter is designed for a dual-mode operation over-moded relativistic backward-wave oscillator. With the converter, the fundamental mode output is achieved. Particle-in-cell simulation shows that the efficiency of beam-wave conversion was over 46% and a pureTM{sub 01} mode output was obtained. Effects of end reflection provided by the mode converter were studied. Adequate TM{sub 01} mode feedback provided by the converter enhances conversion efficiency. The distance between the mode converter and extraction cavity critically affect the generation of microwaves depending on the reflection phase of TM{sub 01} mode feedback.

  8. Effect of Dual-Function Nano-Structured Silicon Oxide Thin Film on Multi-Junction Solar Cells

    SciTech Connect (OSTI)

    Yan, B.; Sivec, L.; Yue, G.; Jiang, C. S.; Yang, J.; Guha, S.

    2011-01-01

    We present our recent study of using nano-structured hydrogenated silicon oxide films (nc-SiO{sub x}:H) as a dual-function layer in multi-junction solar cells. The nc-SiO{sub x}:H films were deposited using very high frequency glow discharge of a SiH{sub 4} (or Si{sub 2}H{sub 6}), CO{sub 2}, PH{sub 3}, and H{sub 2} gas mixture. By optimizing deposition parameters, we obtained 'dual function' nc-SiO{sub x}:H material characterized by a conductivity suitable for use as an n layer and optical properties suitable for use as an inter-reflection layer. We tested the nc-SiO{sub x}:H by replacing the normal n-type material in the tunnel junction of a multi-junction structure. The advantage of the dual-function nc-SiO{sub x}:H layer is twofold; one is to simplify the cell structure, and the other is to reduce any optical loss associated with the inter-reflection layer. Quantum efficiency measurements show the gain in top cell current is equal to or greater than the loss in bottom cell current for a-Si:H/nc-Si:H structures. In addition, a thinner a-Si:H top cell with the nc-SiO{sub x}:H n layer improves the top-cell stability, thereby providing higher stabilized solar cell efficiency. We also used the dual-function layer between the middle and the bottom cells in a-Si:H/a-SiGe:H/nc-Si:H triple-junction structures. The gain in the middle cell current is {approx}1.0 mA/cm{sup 2}, leading to an initial active-area efficiency of 14.8%.

  9. Method to improve cancerous lesion detection sensitivity in a dedicated dual-head scintimammography system

    DOE Patents [OSTI]

    Kieper, Douglas Arthur; Majewski, Stanislaw; Welch, Benjamin L.

    2012-07-03

    An improved method for enhancing the contrast between background and lesion areas of a breast undergoing dual-head scintimammographic examination comprising: 1) acquiring a pair of digital images from a pair of small FOV or mini gamma cameras compressing the breast under examination from opposing sides; 2) inverting one of the pair of images to align or co-register with the other of the images to obtain co-registered pixel values; 3) normalizing the pair of images pixel-by-pixel by dividing pixel values from each of the two acquired images and the co-registered image by the average count per pixel in the entire breast area of the corresponding detector; and 4) multiplying the number of counts in each pixel by the value obtained in step 3 to produce a normalization enhanced two dimensional contrast map. This enhanced (increased contrast) contrast map enhances the visibility of minor local increases (uptakes) of activity over the background and therefore improves lesion detection sensitivity, especially of small lesions.

  10. Method to improve cancerous lesion detection sensitivity in a dedicated dual-head scintimammography system

    DOE Patents [OSTI]

    Kieper, Douglas Arthur; Majewski, Stanislaw; Welch, Benjamin L.

    2008-10-28

    An improved method for enhancing the contrast between background and lesion areas of a breast undergoing dual-head scintimammographic examination comprising: 1) acquiring a pair of digital images from a pair of small FOV or mini gamma cameras compressing the breast under examination from opposing sides; 2) inverting one of the pair of images to align or co-register with the other of the images to obtain co-registered pixel values; 3) normalizing the pair of images pixel-by-pixel by dividing pixel values from each of the two acquired images and the co-registered image by the average count per pixel in the entire breast area of the corresponding detector; and 4) multiplying the number of counts in each pixel by the value obtained in step 3 to produce a normalization enhanced two dimensional contrast map. This enhanced (increased contrast) contrast map enhances the visibility of minor local increases (uptakes) of activity over the background and therefore improves lesion detection sensitivity, especially of small lesions.

  11. Designing Dual-functionalized Gels for Self-reconfiguration and Autonomous Motion

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kuksenok, Olga; Balazs, Anna C.

    2015-04-30

    Human motion is enabled by the concerted expansion and contraction of interconnected muscles that are powered by inherent biochemical reactions. One of the challenges in the field of biomimicry is eliciting this form of motion from purely synthetic materials, which typically do not generate internalized reactions to drive mechanical action. Moreover, for practical applications, this bio-inspired motion must be readily controllable. Herein, we develop a computational model to design a new class of polymer gels where structural reconfigurations and internalized reactions are intimately linked to produce autonomous motion, which can be directed with light. These gels contain both spirobenzopyran (SP)more » chromophores and the ruthenium catalysts that drive the oscillatory Belousov-Zhabotinsky (BZ) reaction. Importantly, both the SP moieties and the BZ reaction are photosensitive. When these dual-functionalized gels are exposed to non-uniform illumination, the localized contraction of the gel (due to the SP moieties) in the presence of traveling chemical waves (due to the BZ reaction) leads to new forms of spontaneous, self-sustained movement, which cannot be achieved by either of the mono-functionalized networks.« less

  12. A dual phased approach for bioremediation of petroleum contaminated soil and ground water

    SciTech Connect (OSTI)

    Kennel, N.D.; Maher, A.; Buckallew, B.

    1994-12-31

    A case study will be presented to demonstrate an effective and timely method of site remediation which yields complete contaminant destruction rather than the contaminant transfer that traditional ground water extraction and treatment techniques result in. By utilizing bioremediation at this site, the client was able to completely degrade the contamination beneath the property, and in the process avoid future liability from transfer of the contamination to another party (i.e. landfill) or phase (i.e. liquid to vapor through air stripping). The provisions of a real estate transaction involving a former service station site in Central Iowa stipulated that the site be remediated prior to title transfer. Previous Environmental Investigative activities revealed significant soil and ground water contamination resulting from over 50 years of diesel and gasoline fuel storage and dispensing operations at the site. Microbial Environmental Services, Inc. (MES) utilized a dual phased bioremediation approach to meet regulatory clean-up guidelines in order for a timely property transfer to occur. To facilitate and expedite ground water remediation, contaminated soil was excavated and remediated via Advanced Biological Surface Treatment (ABST) techniques. ABST techniques are utilized by MES to treat excavated soil in closed cell to control emissions and treatment conditions. Following contaminant source removal, ground water was extracted and treated in a submerged, fixed film, flow through 1,000 gallon fixed film bioreactor at a rate of 2.5 gallons per minute.

  13. Particle formation and its control in dual frequency plasma etching reactors

    SciTech Connect (OSTI)

    Kim, Munsu; Cheong, Hee-Woon; Whang, Ki-Woong

    2015-07-15

    The behavior of a particle cloud in plasma etching reactors at the moment when radio frequency (RF) power changes, that is, turning off and transition steps, was observed using the laser-light-scattering method. Two types of reactors, dual-frequency capacitively coupled plasma (CCP) and the hybrid CCP/inductively coupled plasma (ICP), were set up for experiments. In the hybrid CCP/ICP reactor (hereafter ICP reactor), the position and shape of the cloud were strongly dependent on the RF frequency. The particle cloud becomes larger and approaches the electrode as the RF frequency increases. By turning the lower frequency power off later with a small delay time, the particle cloud is made to move away from the electrode. Maintaining lower frequency RF power only was also helpful to reduce the particle cloud size during this transition step. In the ICP reactor, a sufficient bias power is necessary to make a particle trap appear. A similar particle cloud to that in the CCP reactor was observed around the sheath region of the lower electrode. The authors can also use the low-frequency effect to move the particle cloud away from the substrate holder if two or more bias powers are applied to the substrate holder. The dependence of the particle behavior on the RF frequencies suggests that choosing the proper frequency at the right moment during RF power changes can reduce particle contamination effectively.

  14. Dual-wavelength millimeter-wave radar measurements of cirrus clouds

    SciTech Connect (OSTI)

    Sekelsky, S.M.; Firda, J.M.; McIntosh, R.E.

    1996-04-01

    In April 1994, the University of Massachusetts` 33-GHz/95-GHz Cloud Profiling Radar System (CPRS) participated in the multi-sensor Remote Cloud Sensing (RCS) Intensive Operation Period (IOP), which was conducted at the Southern Great Plains Cloud and Radiation Testbed (CART). During the 3-week experiment, CPRS measured a variety of cloud types and severe weather. In the context of global warming, the most significant measurements are dual-frequency observations of cirrus clouds, which may eventually be used to estimate ice crystal size and shape. Much of the cirrus data collected with CPRS show differences between 33-GHz and 95-GHz reflectivity measurements that are correlated with Doppler estimates of fall velocity. Because of the small range of reflectivity differences, a precise calibration of the radar is required and differential attenuation must also be removed from the data. Depolarization, which is an indicator of crystal shape, was also observed in several clouds. In this abstract we present examples of Mie scattering from cirrus and estimates of differential attenuation due to water vapor and oxygen that were derived from CART radiosonde measurements.

  15. Electrically and magnetically dual-driven Janus particles for handwriting-enabled electronic paper

    SciTech Connect (OSTI)

    Komazaki, Y. Hirama, H.; Torii, T.

    2015-04-21

    In this work, we describe the synthesis of novel electrically and magnetically dual-driven Janus particles for a handwriting-enabled twisting ball display via the microfluidic technique. One hemisphere of the Janus particles contains a charge control agent, which allows the display color to be controlled by applying a voltage and superparamagnetic nanoparticles, allows handwriting by applying a magnetic field to the display. We fabricated a twisting ball display utilizing these Janus particles and tested the electric color control and handwriting using a magnet. As a result, the display was capable of permitting handwriting with a small magnet in addition to conventional color control using an applied voltage (80 V). Handwriting performance was improved by increasing the concentration of superparamagnetic nanoparticles and was determined to be possible even when 80 V was applied across the electrodes for 4 wt. % superparamagnetic nanoparticles in one hemisphere. This improvement was impossible when the concentration was reduced to 2 wt. % superparamagnetic nanoparticles. The technology presented in our work can be applied to low-cost, lightweight, highly visible, and energy-saving electronic message boards and large whiteboards because the large-size display can be fabricated easily due to its simple structure.

  16. Field emission spectroscopy evidence for dual-barrier electron tunnelling in nanographite

    SciTech Connect (OSTI)

    Bandurin, D. A.; Kleshch, V. I.; Mingels, S.; Ltzenkirchen-Hecht, D.; Mller, G.; Obraztsov, A. N.

    2015-06-08

    Nanocarbon films with upstanding flake-like graphite crystallites of nanometre thickness were fabricated by carbon condensation from a methanehydrogen gas mixture activated by a direct-current discharge. The nanographite (NG) crystallites are composed of a few graphene layers. The adjacent atomic layers are connected partially at the edges of the crystallites to form strongly curved graphene structures. The extraordinary field emission (FE) properties were revealed for the NG films with an average current density of a few mA/cm{sup 2}, reproducibly obtained at a macroscopic applied field of about 1?V/?m. The integral FE currentvoltage curves and electron spectra (FEES) of NG cathodes with multiple emitters were measured in a triode configuration. Most remarkably, above a threshold field, two peaks were revealed in FEES with different field-dependent shifts to lower energies. This behaviour evidences electron emission through a dual potential barrier, corresponding to carboncarbon heterostructure formed as a result of the graphene bending.

  17. Imaging system for cardiac planar imaging using a dedicated dual-head gamma camera

    SciTech Connect (OSTI)

    Majewski, Stanislaw; Umeno, Marc M.

    2011-09-13

    A cardiac imaging system employing dual gamma imaging heads co-registered with one another to provide two dynamic simultaneous views of the heart sector of a patient torso. A first gamma imaging head is positioned in a first orientation with respect to the heart sector and a second gamma imaging head is positioned in a second orientation with respect to the heart sector. An adjustment arrangement is capable of adjusting the distance between the separate imaging heads and the angle between the heads. With the angle between the imaging heads set to 180 degrees and operating in a range of 140-159 keV and at a rate of up to 500kHz, the imaging heads are co-registered to produce simultaneous dynamic recording of two stereotactic views of the heart. The use of co-registered imaging heads maximizes the uniformity of detection sensitivity of blood flow in and around the heart over the whole heart volume and minimizes radiation absorption effects. A normalization/image fusion technique is implemented pixel-by-corresponding pixel to increase signal for any cardiac region viewed in two images obtained from the two opposed detector heads for the same time bin. The imaging system is capable of producing enhanced first pass studies, bloodpool studies including planar, gated and non-gated EKG studies, planar EKG perfusion studies, and planar hot spot imaging.

  18. Designing Dual-functionalized Gels for Self-reconfiguration and Autonomous Motion

    SciTech Connect (OSTI)

    Kuksenok, Olga; Balazs, Anna C.

    2015-04-30

    Human motion is enabled by the concerted expansion and contraction of interconnected muscles that are powered by inherent biochemical reactions. One of the challenges in the field of biomimicry is eliciting this form of motion from purely synthetic materials, which typically do not generate internalized reactions to drive mechanical action. Moreover, for practical applications, this bio-inspired motion must be readily controllable. Herein, we develop a computational model to design a new class of polymer gels where structural reconfigurations and internalized reactions are intimately linked to produce autonomous motion, which can be directed with light. These gels contain both spirobenzopyran (SP) chromophores and the ruthenium catalysts that drive the oscillatory Belousov-Zhabotinsky (BZ) reaction. Importantly, both the SP moieties and the BZ reaction are photosensitive. When these dual-functionalized gels are exposed to non-uniform illumination, the localized contraction of the gel (due to the SP moieties) in the presence of traveling chemical waves (due to the BZ reaction) leads to new forms of spontaneous, self-sustained movement, which cannot be achieved by either of the mono-functionalized networks.

  19. Operational experience and evaluation of a dual-element stretched-membrane heliostat

    SciTech Connect (OSTI)

    Strachan, J.W.; Van Der Geest, J.

    1994-01-01

    A dual-element, stretched-membrane central receiver heliostat was designed and manufactured in 1989, by a private US company engaged in the development of commercial central receiver solar technology. The two-module collector, with a collection area of 97.5 m{sup 2}, extends stretched-membrane mirror technology on several fronts with face-down stow capability and a digital controller that integrates tracking and focusing control on a single programmable control board. The solar collector was installed at Sandia`s National Solar Thermal Test Facility in Albuquerque, New Mexico and evaluated over a three-and-a-half year period which ended in September 1993. The measured performance and the operational and maintenance characteristics of this commercial prototype are the subject of this report. The results of beam quality measurements, tracking repeatability tests, measurements of beam movement in elevated winds, performance tests of the focusing system, and all-day beam quality and tracking tests are presented, and the authors offer a detailed discussion of the knowledge gained through operation and maintenance and of the improvements made or suggested to the heliostat`s design.

  20. System-independent characterization of materials using dual-energy computed tomography

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Azevedo, Stephen G.; Martz, Jr., Harry E.; Aufderheide, III, Maurice B.; Brown, William D.; Champley, Kyle M.; Kallman, Jeffrey S.; Roberson, G. Patrick; Schneberk, Daniel; Seetho, Isaac M.; Smith, Jerel A.

    2016-02-01

    In this study, we present a new decomposition approach for dual-energy computed tomography (DECT) called SIRZ that provides precise and accurate material description, independent of the scanner, over diagnostic energy ranges (30 to 200 keV). System independence is achieved by explicitly including a scanner-specific spectral description in the decomposition method, and a new X-ray-relevant feature space. The feature space consists of electron density, ρe, and a new effective atomic number, Ze, which is based on published X-ray cross sections. Reference materials are used in conjunction with the system spectral response so that additional beam-hardening correction is not necessary. The techniquemore » is tested against other methods on DECT data of known specimens scanned by diverse spectra and systems. Uncertainties in accuracy and precision are less than 3% and 2% respectively for the (ρe, Ze) results compared to prior methods that are inaccurate and imprecise (over 9%).« less

  1. Mapping hidden aircraft defects with dual-band infrared computed tomography

    SciTech Connect (OSTI)

    Del Grande, N.K.; Durbin, P.F.

    1995-04-03

    Infrared computed tomography (IRCT) is a promising, non-contact, nondestructive evaluation tool used to inspect the mechanical integrity of large structures. We describe on-site, proof-of-principle demonstrations of IRCt to inspect defective metallic and composite structures. The IRCT system captures time sequences of heat-stimulated, dual-band infrared (DBIR) thermal maps for flash-heated and naturally-heated targets. Our VIEW algorithms produce co-registered thermal, thermal inertia, and thermal-timegram maps from which we quantify the percent metal-loss corrosion damage for airframes and the defect sites, depths, and host-material physical properties for composite structures. The IRCT method clarifies the type of defect, e.g., corrosion, fabrication, foreign-material insert, delamination, unbond, void, and quantifies the amount of damage from the defect, e.g., the percent metal-loss from corrosion in metal structures, the depth, thickness, and areal extent of heat damage in multi-layered composite materials. Potential long-term benefits of IRCT technology are in-service monitoring of incipient corrosion damage, to avoid catastrophic failure and production-monitoring of cure states for composite materials.

  2. Scaling studies with the dual crystal spectrometer at the OMEGA-EP laser facility

    SciTech Connect (OSTI)

    Szabo, C. I.; Feldman, U.; Workman, J.; Flippo, K.; Seely, J. F.; Hudson, L. T.; Henins, A.

    2010-10-15

    The dual crystal spectrometer (DCS) is an approved diagnostic at the OMEGA and the OMEGA-EP laser facilities for the measurement of high energy x-rays in the 11-90 keV energy range, e.g., for verification of the x-ray spectrum of backlighter targets of point projection radiography experiments. DCS has two cylindrically bent transmission crystal channels with image plate detectors at distances behind the crystals close to the size of the respective Rowland circle diameters taking advantage of the focusing effect of the cylindrically bent geometry. DCS, with a source to crystal distance of 1.2 m, provides the required energy dispersion for simultaneous detection of x-rays in a low energy channel (11-45 keV) and a high-energy channel (19-90 keV). A scaling study is described for varied pulse length with unchanged laser conditions (energy, focusing). The study shows that the K{alpha} line intensity is not strongly dependent on the length of the laser pulse.

  3. Linearly Organized Turbulence Structures Observed Over a Suburban Area by Dual-Doppler Lidar

    SciTech Connect (OSTI)

    Newsom, Rob K.; Calhoun, Ron; Ligon, David; Allwine, K Jerry

    2008-04-01

    Dual-Doppler lidar observations are used to investigate the structure and evolution of surface layer flow over a suburban area. The observations were made during the Joint Urban 2003 (JU2003) field experiment in Oklahoma City in the summer of 2003. This study focuses specifically on a 10-hour sequence of scan data beginning shortly after noon local time on July 7, 2003. During this period two coherent Doppler lidars performed overlapping low elevation angle sector scans upwind and south of Oklahoma Citys central business district (CBD). Radial velocity data from the two lidars are processed to reveal the structure and evolution of the horizontal velocity field in the surface layer throughout the afternoon and evening transition periods. The retrieved velocity fields clearly show a tendency for turbulence structures to be elongated in the direction of the mean flow throughout the entire 10-hour study period. As the stratification changed from unstable to weakly stable the turbulence structures became increasingly more linearly organized, and the cross-stream separation between high- and low-speed regoins decreased. The spatially resolved velocity fields are used to estimate streamwise and cross-stream turbulence length scales as functions of stability.

  4. COMPARISON OF EXPERIMENTAL RESULTS TO CFD MODELS FOR BLENDING IN A TANK USING DUAL OPPOSING JETS

    SciTech Connect (OSTI)

    Leishear, R.

    2011-08-07

    Research has been completed in a pilot scale, eight foot diameter tank to investigate blending, using a pump with dual opposing jets. The jets re-circulate fluids in the tank to promote blending when fluids are added to the tank. Different jet diameters and different horizontal and vertical orientations of the jets were investigated. In all, eighty five tests were performed both in a tank without internal obstructions and a tank with vertical obstructions similar to a tube bank in a heat exchanger. These obstructions provided scale models of several miles of two inch diameter, serpentine, vertical cooling coils below the liquid surface for a full scale, 1.3 million gallon, liquid radioactive waste storage tank. Two types of tests were performed. One type of test used a tracer fluid, which was homogeneously blended into solution. Data were statistically evaluated to determine blending times for solutions of different density and viscosity, and the blending times were successfully compared to computational fluid dynamics (CFD) models. The other type of test blended solutions of different viscosity. For example, in one test a half tank of water was added to a half tank of a more viscous, concentrated salt solution. In this case, the fluid mechanics of the blending process was noted to significantly change due to stratification of fluids. CFD models for stratification were not investigated. This paper is the fourth in a series of papers resulting from this research (Leishear, et.al. [1- 4]), and this paper documents final test results, statistical analysis of the data, a comparison of experimental results to CFD models, and scale-up of the results to a full scale tank.

  5. Inspection of the Department`s export licensing process for dual-use and munitions commodities

    SciTech Connect (OSTI)

    Not Available

    1993-08-10

    The purpose of our inspection was to review the Department of Energy`s (Energy) export licensing process for dual-use and military (munitions) commodities subject to nuclear nonproliferation controls. Specifically, we reviewed Energy`s authorities, procedures, and policies pertaining to the export licensing process and examined procedures for safeguarding data transmitted between Energy and other agencies involved in the export licensing process. We also reviewed Energy`s role as a member of the Subgroup on Nuclear Export Coordination. Our review of the sample of 60 export cases did not find evidence to lead us to believe that Energy`s recommendations for these cases were inappropriate or incorrect. We identified, however, problems regarding management systems associated with the export license review process. We found that without documentation supporting export licensing decisions by the Export Control Operations Division (ECOD), we could not determine whether ECOD analysts considered all required criteria in their review of export cases referred to Energy. For example, we found that the ECOD did not retain records documenting the bases for its advice, recommendations, or decisions regarding its reviews of export license cases or revisions to lists of controlled commodities and, therefore, was not in compliance with certain provisions of the Export Administration Act, as amended, and Energy records management directives. Additionally, we found that the degree of compliance by Energy with the export licensing review criteria contained in the Export Administration Regulations and the Nuclear Non-Proliferation Act of 1978 could not be determined because ECOD did not retain records documenting the bases for its advice and recommendations on export cases.

  6. MONICA: a compact, portable dual gamma camera system for mouse whole-body imaging

    SciTech Connect (OSTI)

    Choyke, Peter L.; Xia, Wenze; Seidel, Jurgen; Kakareka, John W.; Pohida, Thomas J.; Milenic, Diane E.; Proffitt, James; Majewski, Stan; Weisenberger, Andrew G.; Green, Michael V.

    2010-04-01

    Introduction We describe a compact, portable dual-gamma camera system (named "MONICA" for MObile Nuclear Imaging CAmeras) for visualizing and analyzing the whole-body biodistribution of putative diagnostic and therapeutic single photon emitting radiotracers in animals the size of mice. Methods Two identical, miniature pixelated NaI(Tl) gamma cameras were fabricated and installed ?looking up? through the tabletop of a compact portable cart. Mice are placed directly on the tabletop for imaging. Camera imaging performance was evaluated with phantoms and field performance was evaluated in a weeklong In-111 imaging study performed in a mouse tumor xenograft model. Results Tc-99m performance measurements, using a photopeak energy window of 140 keV?10%, yielded the following results: spatial resolution (FWHM at 1 cm), 2.2 mm; sensitivity, 149 cps (counts per seconds)/MBq (5.5 cps/μCi); energy resolution (FWHM, full width at half maximum), 10.8%; count rate linearity (count rate vs. activity), r2=0.99 for 0?185 MBq (0?5 mCi) in the field of view (FOV); spatial uniformity, <3% count rate variation across the FOV. Tumor and whole-body distributions of the In-111 agent were well visualized in all animals in 5-min images acquired throughout the 168-h study period. Conclusion Performance measurements indicate that MONICA is well suited to whole-body single photon mouse imaging. The field study suggests that inter-device communications and user-oriented interfaces included in the MONICA design facilitate use of the system in practice. We believe that MONICA may be particularly useful early in the (cancer) drug development cycle where basic whole-body biodistribution data can direct future development of the agent under study and where logistical factors, e.g., limited imaging space, portability and, potentially, cost are important.

  7. TU-F-18A-02: Iterative Image-Domain Decomposition for Dual-Energy CT

    SciTech Connect (OSTI)

    Niu, T; Dong, X; Petrongolo, M; Zhu, L

    2014-06-15

    Purpose: Dual energy CT (DECT) imaging plays an important role in advanced imaging applications due to its material decomposition capability. Direct decomposition via matrix inversion suffers from significant degradation of image signal-to-noise ratios, which reduces clinical value. Existing de-noising algorithms achieve suboptimal performance since they suppress image noise either before or after the decomposition and do not fully explore the noise statistical properties of the decomposition process. We propose an iterative image-domain decomposition method for noise suppression in DECT, using the full variance-covariance matrix of the decomposed images. Methods: The proposed algorithm is formulated in the form of least-square estimation with smoothness regularization. It includes the inverse of the estimated variance-covariance matrix of the decomposed images as the penalty weight in the least-square term. Performance is evaluated using an evaluation phantom (Catphan 600) and an anthropomorphic head phantom. Results are compared to those generated using direct matrix inversion with no noise suppression, a de-noising method applied on the decomposed images, and an existing algorithm with similar formulation but with an edge-preserving regularization term. Results: On the Catphan phantom, our method retains the same spatial resolution as the CT images before decomposition while reducing the noise standard deviation of decomposed images by over 98%. The other methods either degrade spatial resolution or achieve less low-contrast detectability. Also, our method yields lower electron density measurement error than direct matrix inversion and reduces error variation by over 97%. On the head phantom, it reduces the noise standard deviation of decomposed images by over 97% without blurring the sinus structures. Conclusion: We propose an iterative image-domain decomposition method for DECT. The method combines noise suppression and material decomposition into an iterative

  8. Dual Layer Monolith ATR of Pyrolysis Oil for Distributed Synthesis Gas Production

    SciTech Connect (OSTI)

    Lawal, Adeniyi

    2012-09-29

    We have successfully demonstrated a novel reactor technology, based on BASF dual layer monolith catalyst, for miniaturizing the autothermal reforming of pyrolysis oil to syngas, the second and most critical of the three steps for thermochemically converting biomass waste to liquid transportation fuel. The technology was applied to aged as well as fresh samples of pyrolysis oil derived from five different biomass feedstocks, namely switch-grass, sawdust, hardwood/softwood, golden rod and maple. Optimization of process conditions in conjunction with innovative reactor system design enabled the minimization of carbon deposit and control of the H2/CO ratio of the product gas. A comprehensive techno-economic analysis of the integrated process using in part, experimental data from the project, indicates (1) net energy recovery of 49% accounting for all losses and external energy input, (2) weight of diesel oil produced as a percent of the biomass to be ~14%, and (3) for a demonstration size biomass to Fischer-Tropsch liquid plant of ~ 2000 daily barrels of diesel, the price of the diesel produced is ~$3.30 per gallon, ex. tax. However, the extension of catalyst life is critical to the realization of the projected economics. Catalyst deactivation was observed and the modes of deactivation, both reversible and irreversible were identified. An effective catalyst regeneration strategy was successfully demonstrated for reversible catalyst deactivation while a catalyst preservation strategy was proposed for preventing irreversible catalyst deactivation. Future work should therefore be focused on extending the catalyst life, and a successful demonstration of an extended (> 500 on-stream hours) catalyst life would affirm the commercial viability of the process.

  9. Growth of c-axis oriented YBaCuO films on oxidized textured Ni sheets and on (100) and (110) oriented NiO single crystals

    SciTech Connect (OSTI)

    Ginsbach, A.; Schneider, R.; Grueninger, H.W.; Grabe, G. )

    1991-03-01

    This paper reports on YBaCuO films grown on oxidized textured Ni sheets and on (100) and (110) oriented NiO single crystals by magnetron sputter deposition from a stoichiometric tubular target. The properties of the YBaCuO films are investigated as function of various preparation parameters (oxidation procedure of the sheets, substrate temperature T{sub s}, HTSC film thickness). At T{sub s} = 780{degrees} C and for film thickness larger than 200 nm, the films have T{sub c} values around 80K. The textures of the Ni sheets, NiO layers and YBaCuO films are determined using X-ray diffraction in Bragg-Brentano geometry and scanning electron microscopy. It is remarkable, that on textured oxidized Ni the YBaCuO films grow c-axis oriented. For comparison the properties of films on differently oriented NiO single crystals are investigated. It is found that the film properties are better on (100) than on (110) surfaces.

  10. Validation of Simplified Load Equations through Loads Measurement and Modeling of a Small Horizontal-Axis Wind Turbine Tower; NREL (National Renewable Energy Laboratory)

    SciTech Connect (OSTI)

    Dana, S.; Damiani, R.; vanDam, J.

    2015-05-18

    As part of an ongoing effort to improve the modeling and prediction of small wind turbine dynamics, NREL tested a small horizontal axis wind turbine in the field at the National Wind Technology Center (NWTC). The test turbine was a 2.1-kW downwind machine mounted on an 18-meter multi-section fiberglass composite tower. The tower was instrumented and monitored for approximately 6 months. The collected data were analyzed to assess the turbine and tower loads and further validate the simplified loads equations from the International Electrotechnical Commission (IEC) 61400-2 design standards. Field-measured loads were also compared to the output of an aeroelastic model of the turbine. Ultimate loads at the tower base were assessed using both the simplified design equations and the aeroelastic model output. The simplified design equations in IEC 61400-2 do not accurately model fatigue loads. In this project, we compared fatigue loads as measured in the field, as predicted by the aeroelastic model, and as calculated using the simplified design equations.

  11. Electric field induced reversible 180° magnetization switching through tuning of interfacial exchange bias along magnetic easy-axis in multiferroic laminates

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xue, Xu; Zhou, Ziyao; Peng, Bin; Zhu, Mingmin; Zhang, Yijun; Ren, Wei; Ren, Tao; Yang, Xi; Nan, Tianxiang; Sun, Nian X.; et al

    2015-11-18

    E-field control of interfacial exchange coupling and deterministic switching of magnetization have been demonstrated in two sets of ferromagnetic(FM)/antiferromagnetic(AFM)/ferroelectric(FE) multiferroic heterostructures, including NiFe/NiCoO/glass/PZN-PT (011) and NiFe/FeMn/glass/PZN-PT (011). We designed this experiment to achieve exchange bias tuning along the magnetic easy axis, which is critical for realizing reversible 180° magnetization deterministic switching at zero or small magnetic bias. Strong exchange coupling were established across AFM-FM interfaces, which plays an important role in voltage control of magnetization switching. Through the competition between the E-field induced uniaxial anisotropy in ferromagnetic layer and unidirectional anisotropy in antiferromagnetic layer, the exchange bias was significantly shiftedmore » by up to |ΔHex|/Hex=8% in NiFe/FeMn/glass/PZN-PT (011) and 13% in NiFe/NiCoO/glass/PZN-PT (011). In addition, the square shape of the hysteresis loop, as well as a strong shape tunability of |ΔHex|/Hc=67.5~125% in NiFe/FeMn/glass/PZN-PT and 30~38% in NiFe/NiCoO/glass/PZN-PT were achieved, which lead to a near 180° magnetization switching. Lastly, electrical tuning of interfacial exchange coupling in FM/AFM/FE systems paves a new way for realizing magnetoelectric random access memories and other memory technologies.« less

  12. Synthesis and characterization of 10?nm thick piezoelectric AlN films with high c-axis orientation for miniaturized nanoelectromechanical devices

    SciTech Connect (OSTI)

    Zaghloul, Usama; Piazza, Gianluca

    2014-06-23

    The scaling of piezoelectric nanoelectromechanical systems (NEMS) is challenged by the synthesis of ultrathin and high quality piezoelectric films on very thin electrodes. We report the synthesis and characterization of the thinnest piezoelectric aluminum nitride (AlN) films (10?nm) ever deposited on ultrathin platinum layers (25?nm) using reactive sputtering. X-ray diffraction, high-resolution transmission electron microscopy, and fast Fourier transform analyses confirmed the proper crystal orientation, fine columnar texture, and the continuous lattice structure within individual grains in the deposited AlN nanometer thick films. The average extracted d{sub 31} piezoelectric coefficient for the synthesized films is ?1.73 pC/N, which is comparable to the reported values for micron thick and highly c-axis oriented AlN films. The 10?nm AlN films were employed to demonstrate two different types of optimized piezoelectric nanoactuators. The unimorph actuators exhibit vertical displacements as large as 1.1??m at 0.7?V for 25??m long and 30?nm thick beams. These results have a great potential to realize miniaturized NEMS relays with extremely low voltage, high frequency resonators, and ultrasensitive sensors.

  13. AXI LLC | Open Energy Information

    Open Energy Info (EERE)

    Boston Area Sector: Biofuels Product: Aims to make commercially feasible strains of algae for fuel production Coordinates: 42.2363996, -71.0200613 Show Map Loading map......

  14. Dual chamber system providing simultaneous etch and deposition on opposing substrate sides for growing low defect density epitaxial layers

    DOE Patents [OSTI]

    Kulkarni, Nagraj S. (Knoxville, TN); Kasica, Richard J. (Ashburn, VA) ,

    2011-03-08

    A dual-chamber reactor can include a housing enclosing a volume having a divider therein, where the divider defines a first chamber and a second chamber. The divider can include a substrate holder that supports at least one substrate and exposes a first side of the substrate to the first chamber and a second side of the substrate to the second chamber. The first chamber can include an inlet for delivering at least one reagent to the first chamber for forming a film on the first side of the substrate, and the second chamber can include a removal device for removing material from the second side of the substrate.

  15. Effect of bulk electric field reversal on the bounce resonance heating in dual-frequency capacitively coupled electronegative plasmas

    SciTech Connect (OSTI)

    Liu Yongxin; Zhang Quanzhi; Liu Jia; Song Yuanhong; Wang Younian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Bogaerts, Annemie [Department of Chemistry, University of Antwerp, Campus Drie Eiken, Universiteitsplein 1, BE-2610 Wilrijk-Antwerp (Belgium)

    2012-09-10

    The electron bounce resonance heating (BRH) in dual-frequency capacitively coupled plasmas operated in oxygen and argon has been studied by different experimental methods. In comparison with the electropositive argon discharge, the BRH in an electronegative discharge occurs at larger electrode gaps. Kinetic particle simulations reveal that in the oxygen discharge, the bulk electric field becomes quite strong and is out of phase with the sheath field. Therefore, it retards the resonant electrons when traversing the bulk, resulting in a suppressed BRH. This effect becomes more pronounced at lower high-frequency power, when the discharge mode changes from electropositive to electronegative.

  16. Heating mode transition in a hybrid direct current/dual-frequency capacitively coupled CF{sub 4} discharge

    SciTech Connect (OSTI)

    Zhang, Quan-Zhi; Wang, You-Nian; Bogaerts, Annemie

    2014-06-14

    Computer simulations based on the particle-in-cell/Monte Carlo collision method are performed to study the plasma characteristics and especially the transition in electron heating mechanisms in a hybrid direct current (dc)/dual-frequency (DF) capacitively coupled CF{sub 4} discharge. When applying a superposed dc voltage, the plasma density first increases, then decreases, and finally increases again, which is in good agreement with experiments. This trend can be explained by the transition between the four main heating modes, i.e., DF coupling, dc and DF coupling, dc source dominant heating, and secondary electron dominant heating.

  17. Electrically tunable zero dispersion wavelengths in photonic crystal fibers filled with a dual frequency addressable liquid crystal

    SciTech Connect (OSTI)

    Wahle, Markus Kitzerow, Heinz-Siegfried

    2015-11-16

    We present a liquid crystal (LC) infiltrated photonic crystal fiber, which enables the electrical tuning of the position of zero dispersion wavelengths (ZDWs). A dual frequency addressable liquid crystal is aligned perpendicular on the inclusion walls of a photonic crystal fiber, which results in an escaped radial director field. The orientation of the LC is controlled by applying an external electric field. Due to the high index of the liquid crystal the fiber guides light by the photonic band gap effect. Multiple ZDWs exist in the visible and near infrared. The positions of the ZDWs can be either blue or red shifted depending on the frequency of the applied voltage.

  18. Electric field induced reversible 180° magnetization switching through tuning of interfacial exchange bias along magnetic easy-axis in multiferroic laminates

    SciTech Connect (OSTI)

    Xue, Xu; Zhou, Ziyao; Peng, Bin; Zhu, Mingmin; Zhang, Yijun; Ren, Wei; Ren, Tao; Yang, Xi; Nan, Tianxiang; Sun, Nian X.; Liu, Ming

    2015-11-18

    E-field control of interfacial exchange coupling and deterministic switching of magnetization have been demonstrated in two sets of ferromagnetic(FM)/antiferromagnetic(AFM)/ferroelectric(FE) multiferroic heterostructures, including NiFe/NiCoO/glass/PZN-PT (011) and NiFe/FeMn/glass/PZN-PT (011). We designed this experiment to achieve exchange bias tuning along the magnetic easy axis, which is critical for realizing reversible 180° magnetization deterministic switching at zero or small magnetic bias. Strong exchange coupling were established across AFM-FM interfaces, which plays an important role in voltage control of magnetization switching. Through the competition between the E-field induced uniaxial anisotropy in ferromagnetic layer and unidirectional anisotropy in antiferromagnetic layer, the exchange bias was significantly shifted by up to |ΔHex|/Hex=8% in NiFe/FeMn/glass/PZN-PT (011) and 13% in NiFe/NiCoO/glass/PZN-PT (011). In addition, the square shape of the hysteresis loop, as well as a strong shape tunability of |ΔHex|/Hc=67.5~125% in NiFe/FeMn/glass/PZN-PT and 30~38% in NiFe/NiCoO/glass/PZN-PT were achieved, which lead to a near 180° magnetization switching. Lastly, electrical tuning of interfacial exchange coupling in FM/AFM/FE systems paves a new way for realizing magnetoelectric random access memories and other memory technologies.

  19. Fibroblast growth factor-2 up-regulates the expression of nestin through the RasRafERKSp1 signaling axis in C6 glioma cells

    SciTech Connect (OSTI)

    Chang, Kai-Wei; Huang, Yuan-Li; Wong, Zong-Ruei; Su, Peng-Han; Huang, Bu-Miin; Ju, Tsai-Kai; Technology Commons, College of Life Science, National Taiwan University, Taipei 106, Taiwan ; Yang, Hsi-Yuan

    2013-05-17

    Highlights: Nestin expression in C6 glioma cells is induced by FGF-2. Nestin expression is induced by FGF-2 via de novo RNA and protein synthesis. The FGFR inhibitor SU5402 blocks the FGF-2-induced nestin expression. The mRNA of FGFR1 and 3 are detected in C6 glioma cells. RasRafERKSp1 signaling pathway is responsibe for FGF-2-induced nestin expression. -- Abstract: Nestin is a 240-kDa intermediate filament protein expressed mainly in neural and myogenic stem cells. Although a substantial number of studies have focused on the expression of nestin during development of the central nervous system, little is known about the factors that induce and regulate its expression. Fibroblast growth factor-2 (FGF-2) is an effective mitogen and stimulates the proliferation and differentiation of a subset of nestin-expressing cells, including neural progenitor cells, glial precursor cells, and smooth muscle cells. To assess whether FGF-2 is a potent factor that induces the expression of nestin, C6 glioma cells were used. The results showed that nestin expression was up-regulated by FGF-2 via de novo RNA and protein synthesis. Our RT-PCR results showed that C6 glioma cells express FGFR1/3, and FGFRs is required for FGF-2-induced nestin expression. Further signaling analysis also revealed that FGF-2-induced nestin expression is mediated through FGFRMAPKERK signaling axis and the transcriptional factor Sp1. These findings provide new insight into the regulation of nestin in glial system and enable the further studies on the function of nestin in glial cells.

  20. SU-E-T-623: Delivery of 3D Conformal Proton-Therapy Fields at Extended Source- To-Axis Distances

    SciTech Connect (OSTI)

    Kryck, E; Slopsema, R

    2014-06-15

    Purpose: To evaluate the dosimetric properties of proton dose distributions delivered at extended source-to-skin distances (SSD). Methods: Radiation was delivered with a gantry-mounted proton double scattering system (Proteus 230, IBA). This system has a maximum field diameter of 24 cm at isocenter and a nominal source-to-axis distance of 230 cm. Dose was measured at nominal SSD as well as at -10, +10, +25, +50, +75, and +100 cm for several range and modulation width combinations. Depth dose distributions were measured with a multi-layer ionization chamber (MLIC), and lateral dose distributions with a 2D ionization chamber array as well as with a diode in a water phantom. Results: The maximum field diameter was found to increase from 24.0 cm at nominal SSD to 29.1 cm and 33.3 cm at +50 cm and +100 cm respectively. Field flatness remained below 3% for all SSD. Tilt in the spread-out Bragg peak depth dose distribution increased with SSD up to 0.4 %-per-g/cm2 at +100 cm. The measured range decreased with 1.1x10-3 g/cm2 per centimeter shift in SSD due to proton energy loss in air, very close to the theoretically calculated value of 1.06x10-3 g/cm3. The output and dose rate decrease with the inverse of the SSD squared as expected. Conclusion: Extending the SSD up to 100 cm increases the maximum field diameter from 24.0 cm to 33.3 cm while the dose uniformity remains acceptable.