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Sample records for ase du ring

  1. SolASE | Open Energy Information

    Open Energy Info (EERE)

    SolASE Jump to: navigation, search Name: SolASE Address: P.O. Box 927122 Place: San Diego, California Zip: 92192 Region: Southern CA Area Sector: Solar Product: Commercializes...

  2. Advanced Solar Electric Inc ASE | Open Energy Information

    Open Energy Info (EERE)

    Inc (ASE) Place: Thousand Oaks, California Zip: 91320 Product: US-based PV system installer. References: Advanced Solar Electric Inc (ASE)1 This article is a stub. You...

  3. American Solar Energy Society ASES | Open Energy Information

    Open Energy Info (EERE)

    Energy Society ASES Jump to: navigation, search Name: American Solar Energy Society (ASES) Place: Boulder, Colorado Zip: 80301 Sector: Solar Product: Dedicated to advancing the use...

  4. DOE Selects ASE to Manage and Operate its National Renewable...

    Office of Environmental Management (EM)

    ASE to Manage and Operate its National Renewable Energy Laboratory DOE Selects ASE to Manage and Operate its National Renewable Energy Laboratory July 29, 2008 - 2:40pm Addthis ...

  5. NREL Solar Researcher Honored with ASES Abbot Award - News Releases | NREL

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

    Solar Researcher Honored with ASES Abbot Award July 21, 2006 Photo of Dr. Chuck Kutscher, recipient of the Charles Greeley Abbot Award. Dr. Chuck Kutscher The American Solar Energy Society (ASES) honored Dr. Chuck Kutscher of the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) with the Charles Greeley Abbot Award during the recent ASES SOLAR 2006 conference. The Abbot Award recognizes individuals who have made significant career contributions to the field of solar

  6. DOE Selects ASE to Manage and Operate its National Renewable Energy

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

    Laboratory | Department of Energy ASE to Manage and Operate its National Renewable Energy Laboratory DOE Selects ASE to Manage and Operate its National Renewable Energy Laboratory July 29, 2008 - 2:40pm Addthis WASHINGTON - The U.S. Department of Energy (DOE) today announced the Alliance for Sustainable Energy (ASE) LLC has been selected as the management and operating contractor for DOE's National Renewable Energy Laboratory (NREL) in Golden, Colorado. The cost-plus award-fee contract is

  7. ASE/CAGI Meeting about Compressors and Compressed Air System Efficiency |

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

    Department of Energy ASE/CAGI Meeting about Compressors and Compressed Air System Efficiency ASE/CAGI Meeting about Compressors and Compressed Air System Efficiency On April 25, 2013, several representatives of energy efficiency advocacy organizations met with staff and members of the Compressed Air and Gas Institute (CAGI) along with some compressed air experts at the offices of the Alliance to Save Energy to explore and discuss a consensus approach to advancing energy efficiency of

  8. Patrick Ring

    Broader source: Energy.gov [DOE]

    Team Leader, Benefits Continuity TeamActing Team Leader, Financial, Audits, and Contracts Services Team Patrick Ring has more than 31 years of federal service between the U.S. Department of...

  9. Ring Leaders

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

    feed-image Digg: ALSBerkeleyLab Facebook Page: 208064938929 Flickr: advancedlightsource/albums Twitter: AdvLightSource YouTube: AdvancedLightSource Ring Leaders Ringleader: Tom Scarvie, Operations Supervisor Print As operations supervisor at the ALS, Tom Scarvie works with the accelerator operators and floor operators to make sure that the machine runs as well as possible and that beamline work is done safely and according to policy. The operations team strives to make sure the ALS is running

  10. Asymmetric dipolar ring

    DOE Patents [OSTI]

    Prosandeev, Sergey A.; Ponomareva, Inna V.; Kornev, Igor A.; Bellaiche, Laurent M.

    2010-11-16

    A device having a dipolar ring surrounding an interior region that is disposed asymmetrically on the ring. The dipolar ring generates a toroidal moment switchable between at least two stable states by a homogeneous field applied to the dipolar ring in the plane of the ring. The ring may be made of ferroelectric or magnetic material. In the former case, the homogeneous field is an electric field and in the latter case, the homogeneous field is a magnetic field.

  11. Stirling engine piston ring

    DOE Patents [OSTI]

    Howarth, Roy B.

    1983-01-01

    A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

  12. X-ray irradiation induced changes in electron transport in stabilized a-Se photoconductors

    SciTech Connect (OSTI)

    Walornyj, M.; Kasap, S. O.

    2013-12-07

    We have examined the effect of high-dose x-ray irradiation on electron transport in stabilized amorphous selenium (a-Se) x-ray photoconductive films (of the type used in x-ray image detectors) by measuring the electron lifetime ?{sub e} through interrupted-field time-of-flight experiments. X-ray induced effects have been examined through two types of experiments. In recovery experiments, the a-Se was preirradiated with and without an applied field (5 V/?m) during irradiation with sufficient dose (typically ?20 Gy at 21 C) to significantly reduce the electron lifetime by ?50%, and then the recovery of the lifetime was monitored as a function of time at three different temperatures, 10 C, 21 C, and 35 C. The lifetime recovery kinetics was exponential with a relaxation time ?{sub r} that is thermally activated with an activation energy of 1.66 eV. ?{sub r} is a few hours at 21 C and only a few minutes at 35 C. In experiments examining the irradiation induced effects, the a-Se film was repeatedly exposed to x-ray radiation and the changes in the drift mobility and lifetime were monitored as a function of accumulated dose D. There was no observable change in the drift mobility. At 21 C, the concentration of x-ray induced deep traps (or capture centers), N{sub d}, increases linearly with D (N{sub d} ? D) whereas at 35 C, the recovery process prevents a linear increase in N{sub d} with D, and N{sub d} saturates. In all cases, even under high dose irradiation (?50 Gy), the lifetime was recoverable to its original equilibrium (pre-exposure) value within a few relaxation times.

  13. THE CHANDRA ACIS SURVEY OF M33 (ChASeM33): THE FINAL SOURCE CATALOG

    SciTech Connect (OSTI)

    Tuellmann, R.; Gaetz, T. J.; Plucinsky, P. P.; Challis, P.; Edgar, R. J.; Kirshner, R. P.; Kuntz, K. D.; Blair, W. P.; Williams, B. F.; Pietsch, W.; Haberl, F.; Long, K. S.; Sasaki, M.; Winkler, P. F.; Pannuti, T. G.; Helfand, D. J.; Hughes, J. P.; Mazeh, T.; Shporer, A.

    2011-04-01

    This study presents the final source catalog of the Chandra ACIS Survey of M33 (ChASeM33). With a total exposure time of 1.4 Ms, ChASeM33 covers {approx}70% of the D{sub 25} isophote (R {approx} 4.0 kpc) of M33 and provides the deepest, most complete, and detailed look at a spiral galaxy in X-rays. The source catalog includes 662 sources, reaches a limiting unabsorbed luminosity of {approx}2.4x10{sup 34} erg s{sup -1} in the 0.35-8.0 keV energy band, and contains source positions, source net counts, fluxes and significances in several energy bands, and information on source variability. The analysis challenges posed by ChASeM33 and the techniques adopted to address these challenges are discussed. To constrain the nature of the detected X-ray source, hardness ratios were constructed and spectra were fit for 254 sources, follow-up MMT spectra of 116 sources were acquired, and cross-correlations with previous X-ray catalogs and other multi-wavelength data were generated. Based on this effort, 183 of the 662 ChASeM33 sources could be identified. Finally, the luminosity function (LF) for the detected point sources as well as the one for the X-ray binaries (XRBs) in M33 is presented. The LFs in the soft band (0.5-2.0 keV) and the hard band (2.0-8.0 keV) have a limiting luminosity at the 90% completeness limit of 4.0 x 10{sup 34} erg s{sup -1} and 1.6 x 10{sup 35} erg s{sup -1}(for D = 817 kpc), respectively, which is significantly lower than what was reported by previous XRB population studies in galaxies more distant than M33. The resulting distribution is consistent with a dominant population of high-mass XRBs as would be expected for M33.

  14. DuPont Biofuels | Open Energy Information

    Open Energy Info (EERE)

    Biofuels Jump to: navigation, search Name: DuPont Biofuels Place: Wilmington, Delaware Zip: 19898 Product: Biofuel technology development subsidiary of DuPont. Co-developing...

  15. ARM - Tree Rings

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

    PastTree Rings Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Tree Rings Tree rings are formed on an annual basis. They are caused by a more rapid growth in the spring followed by slower growth the rest of the year. Using a tree ring borer you can examine these rings and glean the following

  16. APS Storage Ring Status

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

    Ring Under Maintenance Operations Messages: Operators in Charge : Dmitriy Ronzhin Floor Coordinator : Wendy VanWingeren (2-0101) Fill Pattern : Problem Information : Last DumpTrip...

  17. APS Storage Ring Parameters

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

    next up previous Next: Main Parameters APS Storage Ring Parameters M. Borland, G. Decker, L. Emery, W. Guo, K. Harkay, V. Sajaev, C.-Y. Yao Advanced Photon Source September 8, 2010...

  18. Applications attract DuPont

    SciTech Connect (OSTI)

    Rotman, D.

    1996-08-07

    Scientists at DuPont say they have demonstrated the first chemical processing application for high-temperature superconducting (HTS) magnets. DuPont says the work, which uses a HTS magnet to separate mineral contaminants from kaolin, points to the feasibility of a range of HTS applications in industrial processing, including those involving polymerization. DuPont`s success comes after 10 years of work to commercialize high-temperature superconductors. And while superconductors have lost much of their luster since the late 1980s, the company says it is still bullish on their prospects. {open_quotes}At the moment, there`s no real market for superconductors,{close_quotes} says Alan Lauder, general manager/superconductivity. But, he says, several potentially lucrative applications could be commercialized within the next several years.

  19. L'Aventure du LHC

    ScienceCinema (OSTI)

    None

    2011-10-06

    Cette présentation s?adressera principalement aux personnes qui ont construit le LHC. La construction du LHC fut longue et difficile. De nombreux problèmes sont apparus en cours de route. Tous ont été résolus grâce au dévouement et à l?engagement du personnel et des collaborateurs. Je reviendrai sur les coups durs et les réussites qui ont marqués ces 15 dernières années et je vous montrerai combien cette machine, le fruit de vos efforts, est extraordinaire.

  20. DuPont hikes butanediol

    SciTech Connect (OSTI)

    Morris, G.D.L.

    1997-05-14

    Butanediol (BDO) and its derivatives continue to be strong, a positive sign for the many companies planning expansions. DuPont - one of only two global producers not planning capacity additions - has announced that it will discontinue all off-schedule pricing for BDO and two important derivatives, tetrahydrofuran (THF) and polytetramethylene ether glycol (PTMEG). DuPont`s list prices are $1.00/lb fob for BDO, about $1.40/lb for THF, and $2.00/lb for PTMEG. The price adjustment is effective this month or as contracts allow.

  1. Unidirectional ring lasers

    DOE Patents [OSTI]

    Hohimer, John P.; Craft, David C.

    1994-01-01

    Unidirectional ring lasers formed by integrating nonreciprocal optical elements into the resonant ring cavity. These optical elements either attenuate light traveling in a nonpreferred direction or amplify light traveling in a preferred direction. In one preferred embodiment the resonant cavity takes the form of a circle with an S-shaped crossover waveguide connected to two points on the interior of the cavity such that light traveling in a nonpreferred direction is diverted from the cavity into the crossover waveguide and reinjected out of the other end of the crossover waveguide into the cavity as light traveling in the preferred direction.

  2. Unidirectional ring lasers

    DOE Patents [OSTI]

    Hohimer, J.P.; Craft, D.C.

    1994-09-20

    Unidirectional ring lasers formed by integrating nonreciprocal optical elements into the resonant ring cavity is disclosed. These optical elements either attenuate light traveling in a nonpreferred direction or amplify light traveling in a preferred direction. In one preferred embodiment the resonant cavity takes the form of a circle with an S-shaped crossover waveguide connected to two points on the interior of the cavity such that light traveling in a nonpreferred direction is diverted from the cavity into the crossover waveguide and reinjected out of the other end of the crossover waveguide into the cavity as light traveling in the preferred direction. 21 figs.

  3. Ring laser scatterometer

    DOE Patents [OSTI]

    Ackermann, Mark; Diels, Jean-Claude

    2005-06-28

    A scatterometer utilizes the dead zone resulting from lockup caused by scatter from a sample located in the optical path of a ring laser at a location where counter-rotating pulses cross. The frequency of one pulse relative to the other is varied across the lockup dead zone.

  4. Storage Ring Parameters

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

    Storage Ring Parameters Print General Parameters Parameter Value Beam particle electron Beam energy 1.9 GeV (1.0-1.9 GeV possible) Injection energy 1.9 GeV (1.0-1.9 GeV possible)...

  5. Photo-crystallization in a-Se layer structures: Effects of film-substrate interface-rigidity

    SciTech Connect (OSTI)

    Lindberg, G. P.; Gross, N.; Weinstein, B. A.; O'Loughlin, T.; Mishchenko, A.; Reznik, A.; Abbaszadeh, S.; Karim, K. S.; Belev, G.

    2014-11-21

    Amorphous selenium (a-Se) films deposited on rigid substrates can undergo photo-induced crystallization (PC) even at temperatures (T) well below the glass transition, T{sub g}???313?K. Substrate-generated shear strain is known to promote the PC process. In the present work, we explore the influence of different substrates (Si and glass), and different film-layer-substrate combinations, on the PC in a variety of a-Se films and film-structures. The intermediate layers (indium tin oxide and polyimide) are chosen to promote conductivity and/or to be a buffer against interface strain in structures of interest for digital imaging applications. The PC characteristics in these samples are evaluated and compared using optical microscopy, atomic-force microscopy, Raman mapping, and T-dependent Raman spectroscopy. Both the presence of a soft intermediate layer, and the thermal softening that occurs for T increasing through T{sub g}, inhibit the tendency for the onset of PC. The extensive PC mapping results in the wide range of samples studied here, as well as the suppression of PC near T{sub g} in this array of samples, strongly support the generality of this behavior. As a consequence, one may expect that the stability of a-Se films against PC can be enhanced by decreasing the rigidity of the film-substrate interface. In this regard, advanced film structures that employ flexible substrates, soft intermediate layers, and/or are designed to be operated near T{sub g} should be explored.

  6. Storage Ring | Advanced Photon Source

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

    The Electron Storage Ring The 7-GeV electrons are injected into the 1104-m-circumference storage ring, a circle of more than 1,000 electromagnets and associated equipment, located...

  7. Storage Ring Parameters

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

    Storage Ring Parameters Storage Ring Parameters Print General Parameters Parameter Value Beam particle electron Beam energy 1.9 GeV (1.0-1.9 GeV possible) Injection energy 1.9 GeV (1.0-1.9 GeV possible) Beam current (all operation is in top-off with ΔI/I ≤ 0.3%) 500 mA in multibunch mode 2 x 17.5 mA in two-bunch mode Filling pattern (multibunch mode) 256-320 bunches; possibility of one or two 5- to 6-mA "camshaft" bunches in filling gaps Bunch spacing: multibunch mode 2 ns Bunch

  8. Building Media, Inc. (Du Pont) (Building America Retrofit Alliance...

    Open Energy Info (EERE)

    America Retrofit Alliance) Place: Wilmington, DE Website: www.prweb.comreleasesDuPont References: Building America Retrofit Alliance Press Release1 BMI Website2 DuPont...

  9. DuPont Danisco Cellulosic Ethanol | Open Energy Information

    Open Energy Info (EERE)

    Danisco Cellulosic Ethanol Jump to: navigation, search Name: DuPont Danisco Cellulosic Ethanol Place: Itasca, Illinois Zip: 60143 Product: DuPont Danisco Cellulosic Ethanol is a...

  10. DuPont Cellulosic Ethanol Biorefinery Opening

    Broader source: Energy.gov [DOE]

    The DuPont cellulosic ethanol facility, opening in Nevada, Iowa, on October 30, will be the largest cellulosic ethanol plant in the world. The U.S. Department of Energy Bioenergy Technologies Office Director, Jonathan Male, alongside senior government officials, DuPont leaders and staff, and local farmers will attend the grand opening ceremony and plant tour.

  11. Split ring containment attachment device

    DOE Patents [OSTI]

    Sammel, Alfred G.

    1996-01-01

    A containment attachment device 10 for operatively connecting a glovebag 200 to plastic sheeting 100 covering hazardous material. The device 10 includes an inner split ring member 20 connected on one end 22 to a middle ring member 30 wherein the free end 21 of the split ring member 20 is inserted through a slit 101 in the plastic sheeting 100 to captively engage a generally circular portion of the plastic sheeting 100. A collar potion 41 having an outer ring portion 42 is provided with fastening means 51 for securing the device 10 together wherein the glovebag 200 is operatively connected to the collar portion 41.

  12. Storage Ring Parameters

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

    Storage Ring Parameters Print General Parameters Parameter Value Beam particle electron Beam energy 1.9 GeV (1.0-1.9 GeV possible) Injection energy 1.9 GeV (1.0-1.9 GeV possible) Beam current (all operation is in top-off with ΔI/I ≤ 0.3%) 500 mA in multibunch mode 2 x 17.5 mA in two-bunch mode Filling pattern (multibunch mode) 256-320 bunches; possibility of one or two 5- to 6-mA "camshaft" bunches in filling gaps Bunch spacing: multibunch mode 2 ns Bunch spacing: two-bunch mode 328

  13. Storage Ring Parameters

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

    Storage Ring Parameters Print General Parameters Parameter Value Beam particle electron Beam energy 1.9 GeV (1.0-1.9 GeV possible) Injection energy 1.9 GeV (1.0-1.9 GeV possible) Beam current (all operation is in top-off with ΔI/I ≤ 0.3%) 500 mA in multibunch mode 2 x 17.5 mA in two-bunch mode Filling pattern (multibunch mode) 256-320 bunches; possibility of one or two 5- to 6-mA "camshaft" bunches in filling gaps Bunch spacing: multibunch mode 2 ns Bunch spacing: two-bunch mode 328

  14. Storage Ring Parameters

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

    Storage Ring Parameters Print General Parameters Parameter Value Beam particle electron Beam energy 1.9 GeV (1.0-1.9 GeV possible) Injection energy 1.9 GeV (1.0-1.9 GeV possible) Beam current (all operation is in top-off with ΔI/I ≤ 0.3%) 500 mA in multibunch mode 2 x 17.5 mA in two-bunch mode Filling pattern (multibunch mode) 256-320 bunches; possibility of one or two 5- to 6-mA "camshaft" bunches in filling gaps Bunch spacing: multibunch mode 2 ns Bunch spacing: two-bunch mode 328

  15. Storage Ring Parameters

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

    Storage Ring Parameters Print General Parameters Parameter Value Beam particle electron Beam energy 1.9 GeV (1.0-1.9 GeV possible) Injection energy 1.9 GeV (1.0-1.9 GeV possible) Beam current (all operation is in top-off with ΔI/I ≤ 0.3%) 500 mA in multibunch mode 2 x 17.5 mA in two-bunch mode Filling pattern (multibunch mode) 256-320 bunches; possibility of one or two 5- to 6-mA "camshaft" bunches in filling gaps Bunch spacing: multibunch mode 2 ns Bunch spacing: two-bunch mode 328

  16. Ion Rings for Magnetic Fusion

    SciTech Connect (OSTI)

    Greenly, John, B.

    2005-07-31

    This Final Technical Report presents the results of the program, Ion Rings for Magnetic Fusion, which was carried out under Department of Energy funding during the period August, 1993 to January, 2005. The central objective of the program was to study the properties of field-reversed configurations formed by ion rings. In order to reach this objective, our experimental program, called the Field-reversed Ion Ring Experiment, FIREX, undertook to develop an efficient, economical technology for the production of field-reversed ion rings. A field-reversed configuration (FRC) in which the azimuthal (field-reversing) current is carried by ions with gyro-radius comparable to the magnetic separatrix radius is called a field-reversed ion ring. A background plasma is required for charge neutralization of the ring, and this plasma will be confined within the ring's closed magnetic flux. Ion rings have long been of interest as the basis of compact magnetic fusion reactors, as the basis for a high-power accelerator for an inertial fusion driver, and for other applications of high power ion beams or plasmas of high energy density. Specifically, the FIREX program was intended to address the longstanding question of the contribution of large-orbit ions to the observed stability of experimental FRCs to the MHD tilt mode. Typical experimental FRCs with s {approx} 2-4, where s is the ratio of separatrix radius to ion gyro-radius, have been stable to tilting, but desired values for a fusion reactor, s > 20, should be unstable. The FIREX ring would consist of a plasma with large s for the background ions, but with s {approx} 1 for the ring ions. By varying the proportions of these two populations, the minimum proportion of large-orbit ions necessary for stability could be determined. The incorporation of large-orbit ions, perhaps by neutral-beam injection, into an FRC has been advanced for the purpose of stabilizing, heating, controlling angular momentum, and aiding the formation of a

  17. DuPont Apollo | Open Energy Information

    Open Energy Info (EERE)

    Kong-based thin-film PV module manufacturer that provides solar energy solutions by doing research and development on PV technology and system. References: DuPont Apollo1 This...

  18. Reflex ring laser amplifier system

    DOE Patents [OSTI]

    Summers, Mark A.

    1985-01-01

    A laser pulse is injected into an unstable ring resonator-amplifier structure. Inside this resonator the laser pulse is amplified, spatially filtered and magnified. The laser pulse is recirculated in the resonator, being amplified, filtered and magnified on each pass. The magnification is chosen so that the beam passes through the amplifier in concentric non-overlapping regions similar to a single pass MOPA. After a number of passes around the ring resonator the laser pulse is spatially large enough to exit the ring resonator system by passing around an output mirror.

  19. Power Ring LLC | Open Energy Information

    Open Energy Info (EERE)

    Power Ring LLC Place: Goleta, California Zip: 93117 Product: Power Ring is a power storage technology developer working on technology developed by parent firm LaunchPoint...

  20. Ring resonant cavities for spectroscopy

    DOE Patents [OSTI]

    Zare, R.N.; Martin, J.; Paldus, B.A.; Xie, J.

    1999-06-15

    Ring-shaped resonant cavities for spectroscopy allow a reduction in optical feedback to the light source, and provide information on the interaction of both s- and p-polarized light with samples. A laser light source is locked to a single cavity mode. An intracavity acousto-optic modulator may be used to couple light into the cavity. The cavity geometry is particularly useful for Cavity Ring-Down Spectroscopy (CRDS). 6 figs.

  1. Ring resonant cavities for spectroscopy

    DOE Patents [OSTI]

    Zare, Richard N.; Martin, Juergen; Paldus, Barbara A.; Xie, Jinchun

    1999-01-01

    Ring-shaped resonant cavities for spectroscopy allow a reduction in optical feedback to the light source, and provide information on the interaction of both s- and p-polarized light with samples. A laser light source is locked to a single cavity mode. An intracavity acousto-optic modulator may be used to couple light into the cavity. The cavity geometry is particularly useful for Cavity Ring-Down Spectroscopy (CRDS).

  2. Collar nut and thrust ring

    DOE Patents [OSTI]

    Lowery, Guy B.

    1991-01-01

    A collar nut comprises a hollow cylinder having fine interior threads at one end for threadably engaging a pump mechanical seal assembly and an inwardly depending flange at the other end. The flange has an enlarged portion with a groove for receiving an O-ring for sealing against the intrusion of pumpage from the exterior. The enlarged portion engages a thrust ring about the pump shaft for crushing a hard O-ring, such as a graphite O-ring. The hard O-ring seals the interior of the mechanical seal assembly and pump housing against the loss of lubricants or leakage of pumpage. The fine threads of the hollow cylinder provide the mechanical advantage for crushing the hard O-ring evenly and easily with a hand tool from the side of the collar nut rather than by tightening a plurality of bolts from the end and streamlines the exterior surface of the mechanical seal. The collar nut avoids the spatial requirements of bolt heads at the end of a seal and associated bolt head turbulence.

  3. Double acting stirling engine piston ring

    DOE Patents [OSTI]

    Howarth, Roy B.

    1986-01-01

    A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

  4. N"I. L-S- Rad. Mat. DU

    Office of Legacy Management (LM)

    N"I. L-S- Rad. Mat. DU DU (UF4) Enr. U. Norm. U Thorium 34 Ti Alloy Subtotals Commercial ... Nuclear 1063- 570 1,484,083.2 14' Thorium Bridge- port Brass 762 380 -o- -o- 380 ...

  5. Concentric ring flywheel without expansion separators

    DOE Patents [OSTI]

    Kuklo, Thomas C.

    1999-01-01

    A concentric ring flywheel wherein the adjacent rings are configured to eliminate the need for differential expansion separators between the adjacent rings. This is accomplished by forming a circumferential step on an outer surface of an inner concentric ring and forming a matching circumferential step on the inner surface of an adjacent outer concentric ring. During operation the circumferential steps allow the rings to differentially expand due to the difference in the radius of the rings without the formation of gaps therebetween, thereby eliminating the need for expansion separators to take up the gaps formed by differential expansion.

  6. Concentric ring flywheel without expansion separators

    DOE Patents [OSTI]

    Kuklo, T.C.

    1999-08-24

    A concentric ring flywheel wherein the adjacent rings are configured to eliminate the need for differential expansion separators between the adjacent rings. This is accomplished by forming a circumferential step on an outer surface of an inner concentric ring and forming a matching circumferential step on the inner surface of an adjacent outer concentric ring. During operation the circumferential steps allow the rings to differentially expand due to the difference in the radius of the rings without the formation of gaps therebetween, thereby eliminating the need for expansion separators to take up the gaps formed by differential expansion. 3 figs.

  7. Conical O-ring seal

    DOE Patents [OSTI]

    Chalfant, G.G. Jr.

    A shipping container for radioactive or other hazardous materials has a conical-shaped closure containing grooves in the conical surface thereof and an O-ring seal incorporated in each of such grooves. The closure and seal provide a much stronger, tighter and compact containment than with a conventional flanged joint.

  8. Conical O-ring seal

    DOE Patents [OSTI]

    Chalfant, Jr., Gordon G.

    1984-01-01

    A shipping container for radioactive or other hazardous materials which has a conical-shaped closure containing grooves in the conical surface thereof and an O-ring seal incorporated in each of such grooves. The closure and seal provide a much stronger, tighter and compact containment than with a conventional flanged joint.

  9. Cavity-locked ring down spectroscopy

    DOE Patents [OSTI]

    Zare, Richard N.; Paldus, Barbara A.; Harb, Charles C.; Spence, Thomas

    2000-01-01

    Distinct locking and sampling light beams are used in a cavity ring-down spectroscopy (CRDS) system to perform multiple ring-down measurements while the laser and ring-down cavity are continuously locked. The sampling and locking light beams have different frequencies, to ensure that the sampling and locking light are decoupled within the cavity. Preferably, the ring-down cavity is ring-shaped, the sampling light is s-polarized, and the locking light is p-polarized. Transmitted sampling light is used for ring-down measurements, while reflected locking light is used for locking in a Pound-Drever scheme.

  10. Ring Energy sro | Open Energy Information

    Open Energy Info (EERE)

    Ring Energy sro Jump to: navigation, search Name: Ring Energy sro Place: Most, Czech Republic Zip: 434 01 Product: Czech developer operating a 2.1MW PV plant in the Czech Republic....

  11. RingCentral Mailboxes | Department of Energy

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

    Mailboxes RingCentral Mailboxes This is a list of each Departmental element's mailbox(es) used for RingCentral during a COOP event. RingCentral Mailboxes (48 KB) Responsible Contacts Bruce Murray HR Policy Advisor E-mail bruce.murray@hq.doe.gov Phone 202-586-3372 More Documents & Publications RingCentral User Guide Audit Report: IG-0845 Audit Report: OAS-L-15-01

  12. Optical fiber having wave-guiding rings

    DOE Patents [OSTI]

    Messerly, Michael J.; Dawson, Jay W.; Beach, Raymond J.; Barty, Christopher P. J.

    2011-03-15

    A waveguide includes a cladding region that has a refractive index that is substantially uniform and surrounds a wave-guiding region that has an average index that is close to the index of the cladding. The wave-guiding region also contains a thin ring or series of rings that have an index or indices that differ significantly from the index of the cladding. The ring or rings enable the structure to guide light.

  13. Reflex ring laser amplifier system

    DOE Patents [OSTI]

    Summers, M.A.

    1983-08-31

    The invention is a method and apparatus for providing a reflex ring laser system for amplifying an input laser pulse. The invention is particularly useful in laser fusion experiments where efficient production of high-energy and high power laser pulses is required. The invention comprises a large aperture laser amplifier in an unstable ring resonator which includes a combination spatial filter and beam expander having a magnification greater than unity. An input pulse is injected into the resonator, e.g., through an aperture in an input mirror. The injected pulse passes through the amplifier and spatial filter/expander components on each pass around the ring. The unstable resonator is designed to permit only a predetermined number of passes before the amplified pulse exits the resonator. On the first pass through the amplifier, the beam fills only a small central region of the gain medium. On each successive pass, the beam has been expanded to fill the next concentric non-overlapping region of the gain medium.

  14. Wavelength-tunable optical ring resonators

    DOE Patents [OSTI]

    Watts, Michael R.; Trotter, Douglas C.; Young, Ralph W.; Nielson, Gregory N.

    2009-11-10

    Optical ring resonator devices are disclosed that can be used for optical filtering, modulation or switching, or for use as photodetectors or sensors. These devices can be formed as microdisk ring resonators, or as open-ring resonators with an optical waveguide having a width that varies adiabatically. Electrical and mechanical connections to the open-ring resonators are made near a maximum width of the optical waveguide to minimize losses and thereby provide a high resonator Q. The ring resonators can be tuned using an integral electrical heater, or an integral semiconductor junction.

  15. Wavelength-tunable optical ring resonators

    DOE Patents [OSTI]

    Watts, Michael R.; Trotter, Douglas C.; Young, Ralph W.; Nielson, Gregory N.

    2011-07-19

    Optical ring resonator devices are disclosed that can be used for optical filtering, modulation or switching, or for use as photodetectors or sensors. These devices can be formed as microdisk ring resonators, or as open-ring resonators with an optical waveguide having a width that varies adiabatically. Electrical and mechanical connections to the open-ring resonators are made near a maximum width of the optical waveguide to minimize losses and thereby provide a high resonator Q. The ring resonators can be tuned using an integral electrical heater, or an integral semiconductor junction.

  16. ASE Program Certification Standards

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

  17. ASES Solar 2015

    Broader source: Energy.gov [DOE]

    Solar 2015 is three-day conference with sessions for discussing pre-publication research at the forefront of your field, forums, and networking opportunities.

  18. DuPont Chemical Vapor Technical Report

    SciTech Connect (OSTI)

    MOORE, T.L.

    2003-10-03

    DuPont Safety Resources was tasked with reviewing the current chemical vapor control practices and providing preventive recommendations on best commercial techniques to control worker exposures. The increased focus of the tank closure project to meet the 2024 Tri-Party Agreement (TPA) milestones has surfaced concerns among some CH2MHill employees and other interested parties. CH2MHill is committed to providing a safe working environment for employees and desires to safely manage the tank farm operations using appropriate control measures. To address worker concerns, CH2MHill has chartered a ''Chemical Vapors Project'' to integrate the activities of multiple CH2MHill project teams, and solicit the expertise of external resources, including an independent Industrial Hygiene expert panel, a communications consultant, and DuPont Safety Resources. Over a three-month time period, DuPont worked with CH2MHill ESH&Q, Industrial Hygiene, Engineering, and the independent expert panel to perform the assessment. The process included overview presentations, formal interviews, informal discussions, documentation review, and literature review. DuPont Safety Resources concluded that it is highly unlikely that workers in the tank farms are exposed to chemicals above established standards. Additionally, the conventional and radiological chemistry is understood, the inherent chemical hazards are known, and the risk associated with chemical vapor exposure is properly managed. The assessment highlighted management's commitment to addressing chemical vapor hazards and controlling the associated risks. Additionally, we found the Industrial Hygiene staff to be technically competent and well motivated. The tank characterization data resides in a comprehensive database containing the tank chemical compositions and relevant airborne concentrations.

  19. Ring magnet firing angle control

    DOE Patents [OSTI]

    Knott, M.J.; Lewis, L.G.; Rabe, H.H.

    1975-10-21

    A device is provided for controlling the firing angles of thyratrons (rectifiers) in a ring magnet power supply. A phase lock loop develops a smooth ac signal of frequency equal to and in phase with the frequency of the voltage wave developed by the main generator of the power supply. A counter that counts from zero to a particular number each cycle of the main generator voltage wave is synchronized with the smooth AC signal of the phase lock loop. Gates compare the number in the counter with predetermined desired firing angles for each thyratron and with coincidence the proper thyratron is fired at the predetermined firing angle.

  20. Fond du Lac Band Leads Climate Resilience Efforts on Lake Superior...

    Energy Savers [EERE]

    Fond du Lac Band Leads Climate Resilience Efforts on Lake Superior Chippewa Indian Reservation Fond du Lac Band Leads Climate Resilience Efforts on Lake Superior Chippewa Indian ...

  1. Cooling system for three hook ring segment

    DOE Patents [OSTI]

    Campbell, Christian X.; Eng, Darryl; Lee, Ching-Pang; Patat, Harry

    2014-08-26

    A triple hook ring segment including forward, midsection and aft mounting hooks for engagement with respective hangers formed on a ring segment carrier for supporting a ring segment panel, and defining a forward high pressure chamber and an aft low pressure chamber on opposing sides of the midsection mounting hook. An isolation plate is provided on the aft side of the midsection mounting hook to form an isolation chamber between the aft low pressure chamber and the ring segment panel. High pressure air is supplied to the forward chamber and flows to the isolation chamber through crossover passages in the midsection hook. The isolation chamber provides convection cooling air to an aft portion of the ring segment panel and enables a reduction of air pressure in the aft low pressure chamber to reduce leakage flow of cooling air from the ring segment.

  2. Interferometric ring lasers and optical devices

    DOE Patents [OSTI]

    Hohimer, J.P.; Craft, D.C.

    1995-03-14

    Two ring diode lasers are optically coupled together to produce tunable, stable output through a Y-junction output coupler which may also be a laser diode or can be an active waveguide. These devices demonstrate a sharp peak in light output with an excellent side-mode-rejection ratio. The rings can also be made of passive or active waveguide material. With additional rings the device is a tunable optical multiplexer/demultiplexer. 11 figs.

  3. Report of the eRHIC Ring-Ring Working Group

    SciTech Connect (OSTI)

    Aschenauer, E. C.; Berg, S.; Blaskiewicz, M.; Brennan, M.; Fedotov, A.; Fischer, W.; Litvinenko, V.; Montag, C.; Palmer, R.; Parker, B.; Peggs, S.; Ptitsyn, V.; Ranjbar, V.; Tepikian, S.; Trbojevic, D.; Willeke, F.

    2015-10-13

    This report evaluates the ring-ring option for eRHIC as a lower risk alternative to the linac-ring option. The reduced risk goes along with a reduced initial luminosity performance. However, a luminosity upgrade path is kept open. This upgrade path consists of two branches, with the ultimate upgrade being either a ring-ring or a linac-ring scheme. The linac-ring upgrade could be almost identical to the proposed linac-ring scheme, which is based on an ERL in the RHIC tunnel. This linac-ring version has been studied in great detail over the past ten years, and its significant risks are known. On the other hand, no detailed work on an ultimate performance ring-ring scenario has been performed yet, other than the development of a consistent parameter set. Pursuing the ring-ring upgrade path introduces high risks and requires significant design work that is beyond the scope of this report.

  4. Condenser for illuminating a ring field

    DOE Patents [OSTI]

    Sweatt, William C.

    1994-01-01

    A series of segments of a parent aspheric mirror having one foci at at a si-point source of radiation and the other foci at the radius of a ring field have all but one or all of their beams translated and rotated by sets of mirrors such that all of the beams pass through the real entrance pupil of a ring field camera about one of the beams and fall onto the ring field radius as a coincident image as an arc of the ring field.

  5. Condenser for illuminating a ring field

    DOE Patents [OSTI]

    Sweatt, W.C.

    1994-11-01

    A series of segments of a parent aspheric mirror having one foci at a point source of radiation and the other foci at the radius of a ring field have all but one or all of their beams translated and rotated by sets of mirrors such that all of the beams pass through the real entrance pupil of a ring field camera about one of the beams and fall onto the ring field radius as a coincident image as an arc of the ring field. 5 figs.

  6. Concrete Pour in NSLS-II Ring

    ScienceCinema (OSTI)

    Bruno Semon

    2013-07-22

    The mezzanine floor of the ring building tunnel for NSLS-II was completed when the last concrete was placed in February 2011.

  7. Spatiotemporal Monte Carlo transport methods in x-ray semiconductor detectors: Application to pulse-height spectroscopy in a-Se

    SciTech Connect (OSTI)

    Fang Yuan; Badal, Andreu; Allec, Nicholas; Karim, Karim S.; Badano, Aldo

    2012-01-15

    Purpose: The authors describe a detailed Monte Carlo (MC) method for the coupled transport of ionizing particles and charge carriers in amorphous selenium (a-Se) semiconductor x-ray detectors, and model the effect of statistical variations on the detected signal. Methods: A detailed transport code was developed for modeling the signal formation process in semiconductor x-ray detectors. The charge transport routines include three-dimensional spatial and temporal models of electron-hole pair transport taking into account recombination and trapping. Many electron-hole pairs are created simultaneously in bursts from energy deposition events. Carrier transport processes include drift due to external field and Coulombic interactions, and diffusion due to Brownian motion. Results: Pulse-height spectra (PHS) have been simulated with different transport conditions for a range of monoenergetic incident x-ray energies and mammography radiation beam qualities. Two methods for calculating Swank factors from simulated PHS are shown, one using the entire PHS distribution, and the other using the photopeak. The latter ignores contributions from Compton scattering and K-fluorescence. Comparisons differ by approximately 2% between experimental measurements and simulations. Conclusions: The a-Se x-ray detector PHS responses simulated in this work include three-dimensional spatial and temporal transport of electron-hole pairs. These PHS were used to calculate the Swank factor and compare it with experimental measurements. The Swank factor was shown to be a function of x-ray energy and applied electric field. Trapping and recombination models are all shown to affect the Swank factor.

  8. Concentric ring flywheel with hooked ring carbon fiber separator/torque coupler

    DOE Patents [OSTI]

    Kuklo, T.C.

    1999-07-20

    A concentric ring flywheel with expandable separators, which function as torque couplers, between the rings to take up the gap formed between adjacent rings due to differential expansion between different radius rings during rotation of the flywheel. The expandable separators or torque couplers include a hook-like section at an upper end which is positioned over an inner ring and a shelf-like or flange section at a lower end onto which the next adjacent outer ring is positioned. As the concentric rings are rotated the gap formed by the differential expansion there between is partially taken up by the expandable separators or torque couplers to maintain torque and centering attachment of the concentric rings. 2 figs.

  9. Concentric ring flywheel with hooked ring carbon fiber separator/torque coupler

    DOE Patents [OSTI]

    Kuklo, Thomas C.

    1999-01-01

    A concentric ring flywheel with expandable separators, which function as torque couplers, between the rings to take up the gap formed between adjacent rings due to differential expansion between different radius rings during rotation of the flywheel. The expandable separators or torque couplers include a hook-like section at an upper end which is positioned over an inner ring and a shelf-like or flange section at a lower end onto which the next adjacent outer ring is positioned. As the concentric rings are rotated the gap formed by the differential expansion there between is partially taken up by the expandable separators or torque couplers to maintain torque and centering attachment of the concentric rings.

  10. Mechanical support of a ceramic gas turbine vane ring

    DOE Patents [OSTI]

    Shi, Jun; Green, Kevin E.; Mosher, Daniel A.; Holowczak, John E.; Reinhardt, Gregory E.

    2010-07-27

    An assembly for mounting a ceramic turbine vane ring onto a turbine support casing comprises a first metal clamping ring and a second metal clamping ring. The first metal clamping ring is configured to engage with a first side of a tab member of the ceramic turbine vane ring. The second metal clamping ring is configured to engage with a second side of the tab member such that the tab member is disposed between the first and second metal clamping rings.

  11. PMIX_Ring patch for SLURM

    Energy Science and Technology Software Center (OSTI)

    2014-04-20

    This code adds an implementation of PMIX_Ring to the existing PM12 Library in the SLURM open source software package (Simple Linux Utility for Resource Management). PMIX_Ring executes a particular communication pattern that is used to bootstrap connections between MPI processes in a parallel job.

  12. Bernstein instability driven by thermal ring distribution

    SciTech Connect (OSTI)

    Yoon, Peter H.; Hadi, Fazal; Qamar, Anisa

    2014-07-15

    The classic Bernstein waves may be intimately related to banded emissions detected in laboratory plasmas, terrestrial, and other planetary magnetospheres. However, the customary discussion of the Bernstein wave is based upon isotropic thermal velocity distribution function. In order to understand how such waves can be excited, one needs an emission mechanism, i.e., an instability. In non-relativistic collision-less plasmas, the only known Bernstein wave instability is that associated with a cold perpendicular velocity ring distribution function. However, cold ring distribution is highly idealized. The present Brief Communication generalizes the cold ring distribution model to include thermal spread, so that the Bernstein-ring instability is described by a more realistic electron distribution function, with which the stabilization by thermal spread associated with the ring distribution is demonstrated. The present findings imply that the excitation of Bernstein waves requires a sufficiently high perpendicular velocity gradient associated with the electron distribution function.

  13. eRHIC ring-ring design with head-on beam-beam compensation

    SciTech Connect (OSTI)

    Montag,C.; Blaskiewicz, M.; Pozdeyev, E.; Fischer, W.; MacKay, W. W.

    2009-05-04

    The luminosity of the eRHIC ring-ring design is limited by the beam-beam effect exerted on the electron beam. Recent simulation studies have shown that the beam-beam limit can be increased by means of an electron lens that compensates the beam-beam effect experienced by the electron beam. This scheme requires proper design of the electron ring, providing the correct betatron phase advance between interaction point and electron lens. We review the performance of the eRHIC ring-ring version and discuss various parameter sets, based on different cooling schemes for the proton/ion beam.

  14. Structure of a BRCA1/BARD1 Complex: a Heterodimeric RING-RING Interaction

    SciTech Connect (OSTI)

    Brzovic, Peter S.; Rajagopal, Ponni; Hoyt, David W.; King, Mary-Claire; Klevit, Rachel E.

    2001-10-01

    The N-terminal RING domain of the breast and ovarian cancer tumor suppressor BRCA1 interacts with multiple cognate proteins, including the RING protein, BARD1. Proper function of the BRCA1 RING domain is critical, as evidenced by the many cancer-predisposing mutations found within this domain. We present the solution structure of the N-terminal RING domain heterodimer of BRCA1 and BARD1. Comparison with the RAG1 RING homodimer reveals the structural diversity of complexes formed by interactions between different RING domains. The BRCA1/BARD1 structure provides a model for its ubiquitin ligase activity, illustrates how the BRCA1 RING domain can be involved in associations with multiple protein partners, and provdes a framework for understanding cancer-causing mutations at the molecular level.

  15. Wedding ring shaped excitation coil

    DOE Patents [OSTI]

    MacLennan, Donald A.; Tsai, Peter

    2001-01-01

    A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and/or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency.

  16. Recycler ring conceptual design study

    SciTech Connect (OSTI)

    Jackson, G.

    1995-07-18

    The Tevatron Collider provides the highest center of mass energy collisions in the world. To fully exploit this unique tool, Fermilab is committed to a program of accelerator upgrades for the purpose of increasing the Collider luminosity. Over the past 7 years the luminosity has been increased from a peak of 1.6{times}10{sup 30}cm{sup {minus}2}sec{sup {minus}1} in 1989 to over 3{times}10{sup 31}cm{sup {minus}2}sec{sup {minus}1} during 1995. The Main Injector will supply a larger flux of protons for antiproton production and more intense proton bunches for use in the Collider, and this is expected to increase the peak luminosity to close to 1{times}10{sup 32}cm{sup {minus}2}sec{sup {minus}1}. Further increases in luminosity will require additional upgrades to the Fermilab accelerator complex. This report documents the design of a new fixed-energy storage ring to be placed in the Main Injector tunnel which will provide an initial factor of 2 increase to 2{times}10{sup 32}cm{sup {minus}2}sec{sup {minus}1}, and ultimately provide the basis for an additional order of magnitude luminosity increase up to 1{times}10{sup 33}cm{sup {minus}2}sec{sup {minus}1}.

  17. Update on the MEIC electron collider ring design (Conference...

    Office of Scientific and Technical Information (OSTI)

    Update on the MEIC electron collider ring design Citation Details In-Document Search Title: Update on the MEIC electron collider ring design The electron collider ring of the ...

  18. Wind turbine ring/shroud drive system

    DOE Patents [OSTI]

    Blakemore, Ralph W.

    2005-10-04

    A wind turbine capable of driving multiple electric generators having a ring or shroud structure for reducing blade root bending moments, hub loads, blade fastener loads and pitch bearing loads. The shroud may further incorporate a ring gear for driving an electric generator. In one embodiment, the electric generator may be cantilevered from the nacelle such that the gear on the generator drive shaft is contacted by the ring gear of the shroud. The shroud also provides protection for the gearing and aids in preventing gear lubricant contamination.

  19. COLLIMATION OPTIMIZATION IN HIGH INTENSITY RINGS.

    SciTech Connect (OSTI)

    CATALAN-LASHERAS,N.

    2001-06-18

    In high intensity proton rings, collimation is needed in order to maintain reasonable levels of residual activation and allow hands-on maintenance. Small acceptance to emittance ratio and restrained longitudinal space become important restrictions when dealing with low energy rings. The constraints and specifications when designing a collimation system for this type of machine will be reviewed. The SNS accumulator ring will serve as an examples long which we will illustrate the optimization path. Experimental studies of collimation with 1.3 GeV proton beams are currently under way in the U-70 machine in Protvino. The first results will be presented.

  20. Adjustable expandable cryogenic piston and ring

    DOE Patents [OSTI]

    Mazur, Peter O.; Pallaver, Carl B.

    1980-01-01

    The operation of a reciprocating expansion engine for cryogenic refrigeration is improved by changing the pistons and rings so that the piston can be operated from outside the engine to vary the groove in which the piston ring is located. This causes the ring, which is of a flexible material, to be squeezed so that its contact with the wall is subject to external control. This control may be made manually or it may be made automatically in response to instruments that sense the amount of blow-by of the cryogenic fluid and adjust for an optimum blow-by.

  1. Online optimization of storage ring nonlinear beam dynamics ...

    Office of Scientific and Technical Information (OSTI)

    Online optimization of storage ring nonlinear beam dynamics Citation Details In-Document Search Title: Online optimization of storage ring nonlinear beam dynamics Authors: Huang,...

  2. An ultimate storage ring lattice with vertical emittance generated...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: An ultimate storage ring lattice with vertical emittance generated by damping wigglers Citation Details In-Document Search Title: An ultimate storage ring lattice...

  3. Online optimization of storage ring nonlinear beam dynamics ...

    Office of Scientific and Technical Information (OSTI)

    Online optimization of storage ring nonlinear beam dynamics Citation Details In-Document Search Title: Online optimization of storage ring nonlinear beam dynamics You are...

  4. Fast ion instability at the Cornell Electron Storage Ring Test...

    Office of Scientific and Technical Information (OSTI)

    Fast ion instability at the Cornell Electron Storage Ring Test Accelerator Citation Details In-Document Search Title: Fast ion instability at the Cornell Electron Storage Ring Test ...

  5. Updates to the International Linear Collider Damping Rings Baseline...

    Office of Scientific and Technical Information (OSTI)

    Updates to the International Linear Collider Damping Rings Baseline Design Citation Details In-Document Search Title: Updates to the International Linear Collider Damping Rings...

  6. From Protein Structure to Function: Ring Cycle for Dilating and...

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

    From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore From Protein Structure to Function: Ring Cycle for Dilating and Constricting the...

  7. Radiation Belts and Ring Current The Energetic Geospace (Conference...

    Office of Scientific and Technical Information (OSTI)

    Conference: Radiation Belts and Ring Current The Energetic Geospace Citation Details In-Document Search Title: Radiation Belts and Ring Current The Energetic Geospace Authors: Reeves, ...

  8. Radiation Belts and Ring Current The Energetic Geospace (Conference...

    Office of Scientific and Technical Information (OSTI)

    Radiation Belts and Ring Current The Energetic Geospace Citation Details In-Document Search Title: Radiation Belts and Ring Current The Energetic Geospace You are accessing a ...

  9. Effect of burst and recombination models for Monte Carlo transport of interacting carriers in a-Se x-ray detectors on Swank noise

    SciTech Connect (OSTI)

    Fang, Yuan; Karim, Karim S.; Badano, Aldo

    2014-01-15

    Purpose: The authors describe the modification to a previously developed Monte Carlo model of semiconductor direct x-ray detector required for studying the effect of burst and recombination algorithms on detector performance. This work provides insight into the effect of different charge generation models for a-Se detectors on Swank noise and recombination fraction. Methods: The proposed burst and recombination models are implemented in the Monte Carlo simulation package, ARTEMIS, developed byFang et al. [Spatiotemporal Monte Carlo transport methods in x-ray semiconductor detectors: Application to pulse-height spectroscopy in a-Se, Med. Phys. 39(1), 308319 (2012)]. The burst model generates a cloud of electron-hole pairs based on electron velocity, energy deposition, and material parameters distributed within a spherical uniform volume (SUV) or on a spherical surface area (SSA). A simple first-hit (FH) and a more detailed but computationally expensive nearest-neighbor (NN) recombination algorithms are also described and compared. Results: Simulated recombination fractions for a single electron-hole pair show good agreement with Onsager model for a wide range of electric field, thermalization distance, and temperature. The recombination fraction and Swank noise exhibit a dependence on the burst model for generation of many electron-hole pairs from a single x ray. The Swank noise decreased for the SSA compared to the SUV model at 4 V/?m, while the recombination fraction decreased for SSA compared to the SUV model at 30 V/?m. The NN and FH recombination results were comparable. Conclusions: Results obtained with the ARTEMIS Monte Carlo transport model incorporating drift and diffusion are validated with the Onsager model for a single electron-hole pair as a function of electric field, thermalization distance, and temperature. For x-ray interactions, the authors demonstrate that the choice of burst model can affect the simulation results for the generation of many

  10. DuPont Technology Breaks Away From Glass

    Broader source: Energy.gov [DOE]

    Delaware-based DuPont is working to develop ultra-thin moisture protective films for photovoltaic panels — so thin they’re about 1,000 times thinner than a human hair.

  11. Proton storage ring: man/machine interface

    SciTech Connect (OSTI)

    Lander, R.F.; Clout, P.N.

    1985-01-01

    The human interface of the Proton Storage Ring Control System at Los Alamos is described in some detail, together with the software environment in which operator interaction programs are written. Some examples of operator interaction programs are given.

  12. Low thermal expansion seal ring support

    DOE Patents [OSTI]

    Dewis, David W.; Glezer, Boris

    2000-01-01

    Today, the trend is to increase the temperature of operation of gas turbine engines. To cool the components with compressor discharge air, robs air which could otherwise be used for combustion and creates a less efficient gas turbine engine. The present low thermal expansion sealing ring support system reduces the quantity of cooling air required while maintaining life and longevity of the components. Additionally, the low thermal expansion sealing ring reduces the clearance "C","C'" demanded between the interface between the sealing surface and the tip of the plurality of turbine blades. The sealing ring is supported by a plurality of support members in a manner in which the sealing ring and the plurality of support members independently expand and contract relative to each other and to other gas turbine engine components.

  13. CORRECTION SYSTEMS UPGRADE FOR THE SNS RING.

    SciTech Connect (OSTI)

    PAPAPHILIPPOU,Y.; GARDNER,C.J.; LEE,Y.Y.; WEI,J.

    2001-06-18

    In view of the changes in the design of the SNS ring from the original FODO lattice [l] to the 220m hybrid lattice [2] and finally 1.3GeV compatible 248m ring [3], complementary studies have been undertaken, in order to upgrade its correction packages. We review the evolution of the correction systems and present the accelerator physics studies for the adopted schemes and powering plan.

  14. Gasket and snap ring installation tool

    DOE Patents [OSTI]

    Southerland, Jr., James M.; Barringer, Jr., Curtis N.

    1994-01-01

    A tool for installing a gasket and a snap ring including a shaft, a first plate attached to the forward end of the shaft, a second plate slidably carried by the shaft, a spring disposed about the shaft between the first and second plates, and a sleeve that is free to slide over the shaft and engage the second plate. The first plate has a loading surface with a loading groove for receiving a snap ring and a shoulder for holding a gasket. A plurality of openings are formed through the first plate, communicating with the loading groove and approximately equally spaced about the groove. A plurality of rods are attached to the second plate, each rod slidable in one of the openings. In use, the loaded tool is inserted into a hollow pipe or pipe fitting having an internal flange and an internal seating groove, such that the gasket is positioned against the flange and the ring is in the approximate plane of the seating groove. The sleeve is pushed against the second plate, sliding the second plate towards the first plate, compressing the spring and sliding the rods forwards in the openings. The rods engage the snap ring and urge the ring from the loading groove into the seating groove.

  15. E I DuPont De Nemours & Co | Open Energy Information

    Open Energy Info (EERE)

    E I DuPont De Nemours & Co Jump to: navigation, search Name: E I DuPont De Nemours & Co Place: Tennessee Website: www.dupont.com Twitter: @dupontnews Facebook: https:...

  16. E I DuPont De Nemours & Co (Texas) | Open Energy Information

    Open Energy Info (EERE)

    E I DuPont De Nemours & Co (Texas) Jump to: navigation, search Name: E I DuPont De Nemours & Co Place: Texas References: EIA Form EIA-861 Final Data File for 2010 - File220101...

  17. Henan Mingdu Wind Power Co Ltd aka He Nan Ming Du Feng Dian Limited...

    Open Energy Info (EERE)

    Mingdu Wind Power Co Ltd aka He Nan Ming Du Feng Dian Limited Company Jump to: navigation, search Name: Henan Mingdu Wind Power Co Ltd (aka He Nan Ming Du Feng Dian Limited...

  18. Soci t d exploitation du parc olien de Mont d H z cques SARL...

    Open Energy Info (EERE)

    Soci t d exploitation du parc olien de Mont d H z cques SARL Jump to: navigation, search Name: Socit d'exploitation du parc olien de Mont d'Hzcques SARL Place:...

  19. DuPont's Journey to Build a Global Cellulosic BioFuel Business...

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

    DuPont's Journey to Build a Global Cellulosic BioFuel Business Enterprise DuPont's Journey to Build a Global Cellulosic BioFuel Business Enterprise Plenary I: Progress in Advanced ...

  20. DuPont’s Journey to Build a Global Cellulosic BioFuel Business Enterprise

    Office of Energy Efficiency and Renewable Energy (EERE)

    Plenary I: Progress in Advanced Biofuels DuPont’s Journey to Build a Global Cellulosic BioFuel Business Enterprise William Provine, Director–Science and Technology External Affairs, DuPont

  1. A new storage-ring light source

    SciTech Connect (OSTI)

    Chao, Alex

    2015-06-01

    A recently proposed technique in storage ring accelerators is applied to provide potential high-power sources of photon radiation. The technique is based on the steady-state microbunching (SSMB) mechanism. As examples of this application, one may consider a high-power DUV photon source for research in atomic and molecular physics or a high-power EUV radiation source for industrial lithography. A less challenging proof-of-principle test to produce IR radiation using an existing storage ring is also considered.

  2. Transport from the Recycler Ring to the Antiproton Source Beamlines

    SciTech Connect (OSTI)

    Xiao, M.; /Fermilab

    2012-05-14

    In the post-NOvA era, the protons are directly transported from the Booster ring to the Recycler ring rather than the Main Injector. For Mu2e and g-2 project, the Debuncher ring will be modified into a Delivery ring to deliver the protons to both Mu2e and g-2 experiments. Therefore, it requires the transport of protons from the Recycler Ring to the Delivery ring. A new transfer line from the Recycler ring to the P1 beamline will be constructed to transport proton beam from the Recycler Ring to existing Antiproton Source beamlines. This new beamline provides a way to deliver 8 GeV kinetic energy protons from the Booster to the Delivery ring, via the Recycler, using existing beam transport lines, and without the need for new civil construction. This paper presents the Conceptual Design of this new beamline.

  3. Electron Storage Ring Development for ICS Sources

    SciTech Connect (OSTI)

    Loewen, Roderick

    2015-09-30

    There is an increasing world-wide interest in compact light sources based on Inverse Compton Scattering. Development of these types of light sources includes leveraging the investment in accelerator technology first developed at DOE National Laboratories. Although these types of light sources cannot replace the larger user-supported synchrotron facilities, they offer attractive alternatives for many x-ray science applications. Fundamental research at the SLAC National Laboratory in the 1990’s led to the idea of using laser-electron storage rings as a mechanism to generate x-rays with many properties of the larger synchrotron light facilities. This research led to a commercial spin-off of this technology. The SBIR project goal is to understand and improve the performance of the electron storage ring system of the commercially available Compact Light Source. The knowledge gained from studying a low-energy electron storage ring may also benefit other Inverse Compton Scattering (ICS) source development. Better electron storage ring performance is one of the key technologies necessary to extend the utility and breadth of applications of the CLS or related ICS sources. This grant includes a subcontract with SLAC for technical personnel and resources for modeling, feedback development, and related accelerator physics studies.

  4. Transverse instability at the recycler ring

    SciTech Connect (OSTI)

    Ng, K.Y.; /Fermilab

    2004-10-01

    Sporadic transverse instabilities have been observed at the Fermilab Recycler Ring leading to increase in transverse emittances and beam loss. The driving source of these instabilities has been attributed to the resistive-wall impedance with space-charge playing an important role in suppressing Landau damping. Growth rates of the instabilities are computed. Remaining problems are discussed.

  5. Ring cavity for a Raman capillary waveguide amplifir

    DOE Patents [OSTI]

    Kurnit, N.A.

    1981-01-27

    A regenerative ring amplifier and regenerative ring oscillator are described which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplified Stokes signal is synchronous with the mode-locked spikes of the incoming CO/sub 2/ laser pump signal.

  6. Ring cavity for a Raman capillary waveguide amplifier

    DOE Patents [OSTI]

    Kurnit, N.A.

    1983-07-19

    Disclosed is a regenerative ring amplifier and regenerative ring oscillator which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO[sub 2] laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplifier Stokes signal is synchronous with the mode-locked spikes of the incoming CO[sub 2] laser pump signal. 6 figs.

  7. Ring cavity for a raman capillary waveguide amplifier

    DOE Patents [OSTI]

    Kurnit, Norman A.

    1983-07-19

    A regenerative ring amplifier and regenerative ring oscillator which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO.sub.2 laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplifier Stokes signal is synchronous with the mode-locked spikes of the incoming CO.sub.2 laser pump signal.

  8. Ring cavity for a Raman capillary waveguide amplifier

    DOE Patents [OSTI]

    Kurnit, N.A.

    1981-01-27

    A regenerative ring amplifier and regenerative ring oscillator are described which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplified Stokes signal is synchronous with the mode-locked spikes of the incoming CO/sub 2/ laser pump signal.

  9. Jump start: DuPont exports its energy management program

    SciTech Connect (OSTI)

    1994-11-23

    In August 1993, DuPont launched its innovative Jump Start program, which called for managers in its 25 largest plants to carry out a 120-day crash effort to find ways to reduce energy use at their facilities. The effort produced ideas that will result in $21.5 million in energy savings over six years, exceeding DuPont`s target. It also kicked off a longer-term program the company hopes will cut as much as $300 million, or 15% from energy bills through 2000.

  10. Space Charge and Equilibrium Emittances in Damping Rings

    SciTech Connect (OSTI)

    Venturini, Marco; Oide, Katsunobu; Wolski, Andy

    2006-06-21

    We present a model of dynamics to account for the possible impact of space charge on the equilibrium emittances in storage rings and apply the model to study the current design of the International Linear Collider (ILC) damping rings.

  11. Ring Cycle for Dilating and Constricting the Nuclear Pore

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

    Ring Cycle for Dilating and Constricting the Nuclear Pore Ring Cycle for Dilating and Constricting the Nuclear Pore Print Thursday, 13 June 2013 09:30 Pictured is an illustration...

  12. Reversible Seeding in Storage Rings (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Electron storage rings can drive high average power light sources, and free-electron ... By maintaining steady-state coherent microbunching at one point in the storage ring, the ...

  13. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

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

    Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Monday, 28 November 2011 14:52 Movement is fundamental to life. It...

  14. Gas insulated transmission line having tapered particle trapping ring

    DOE Patents [OSTI]

    Cookson, Alan H.

    1982-01-01

    A gas-insulated transmission line includes an outer sheath, an inner conductor, insulating supports and an insulating gas. A particle-trapping ring is secured to each insulating support, and it is comprised of a central portion and two tapered end portions. The ends of the particle trapping ring have a smaller diameter than the central portion of the ring, so as to enable the use of the particle trapping ring in a curved transmission line.

  15. Storage ring development at the National Synchrotron Light Source

    SciTech Connect (OSTI)

    Krinsky, S.; Bittner, J.; Fauchet, A.M.; Johnson, E.D.; Keane, J.; Murphy, J.; Nawrocky, R.J.; Rogers, J.; Singh, O.V.; Yu, L.H.

    1991-09-01

    This report contains papers on the following topics: Transverse Beam Profile Monitor; Bunch Length Measurements in the VUV Storage Ring; Photoelectric Effect Photon Beam Position Monitors; RF Receivers for Processing Electron Beam Pick-up Electrode Signals; Real-Time Global Orbit Feedback Systems; Local Orbit Feedback; Active Interlock System for High Power Insertion Devices in the X-ray Ring; Bunch Lengthening Cavity for the VUV Ring; SXLS Storage Ring Design.

  16. Effect of burst and recombination models for Monte Carlo transport of interacting carriers in a-Se x-ray detectors on Swank noise

    SciTech Connect (OSTI)

    Fang, Yuan; Karim, Karim S.; Badano, Aldo

    2014-01-15

    Purpose: The authors describe the modification to a previously developed Monte Carlo model of semiconductor direct x-ray detector required for studying the effect of burst and recombination algorithms on detector performance. This work provides insight into the effect of different charge generation models for a-Se detectors on Swank noise and recombination fraction. Methods: The proposed burst and recombination models are implemented in the Monte Carlo simulation package, ARTEMIS, developed byFang et al. [“Spatiotemporal Monte Carlo transport methods in x-ray semiconductor detectors: Application to pulse-height spectroscopy in a-Se,” Med. Phys. 39(1), 308–319 (2012)]. The burst model generates a cloud of electron-hole pairs based on electron velocity, energy deposition, and material parameters distributed within a spherical uniform volume (SUV) or on a spherical surface area (SSA). A simple first-hit (FH) and a more detailed but computationally expensive nearest-neighbor (NN) recombination algorithms are also described and compared. Results: Simulated recombination fractions for a single electron-hole pair show good agreement with Onsager model for a wide range of electric field, thermalization distance, and temperature. The recombination fraction and Swank noise exhibit a dependence on the burst model for generation of many electron-hole pairs from a single x ray. The Swank noise decreased for the SSA compared to the SUV model at 4 V/μm, while the recombination fraction decreased for SSA compared to the SUV model at 30 V/μm. The NN and FH recombination results were comparable. Conclusions: Results obtained with the ARTEMIS Monte Carlo transport model incorporating drift and diffusion are validated with the Onsager model for a single electron-hole pair as a function of electric field, thermalization distance, and temperature. For x-ray interactions, the authors demonstrate that the choice of burst model can affect the simulation results for the generation

  17. Damping ring rf system for SLC

    SciTech Connect (OSTI)

    Allen, M.A.; Schwarz, H.D.; Wilson, P.B.

    1983-01-01

    The linear collider project at SLAC contains two damping rings to reduce the emittance of short electron or positron bunches which contain 5 x 10/sup 10/ particles per bunch. Two of these bunches are stored at a time and then extracted for acceleration in the collider. The rf system is subject to strong transients in beam loading. A computer model is used to optimize capture while minimizing rf power. The introduction of phase jump in the rf drive at injection time together with offsets in the tuning loops of the rf cavities when no beam is stored allows optimum performance under heavy beam load conditions. The rf system (800 kV at 714 MHz) for the electron damping ring has been built, tested and installed, and is being tested with beam.

  18. Drum ring removal/installation tool

    SciTech Connect (OSTI)

    Andrade, William Andrew

    2006-11-14

    A handheld tool, or a pair of such tools, such as for use in removing/installing a bolt-type clamping ring on a container barrel/drum, where the clamping ring has a pair of clamping ends each with a throughbore. Each tool has an elongated handle and an elongated lever arm transversely connected to one end of the handle. The lever arm is capable of being inserted into the throughbore of a selected clamping end and leveraged with the handle to exert a first moment on the selected clamping end. Each tool also has a second lever arm, such as a socket with an open-ended slot, which is suspended alongside the first lever arm. The second lever arm is capable of engaging the selected clamping end and being leveraged with the handle to exert a second moment which is orthogonal to the first moment. In this manner, the first and second moments operate to hold the selected clamping end fixed relative to the tool so that the selected clamping end may be controlled with the handle. The pair of clamping ends may also be simultaneously and independently controlled with the use of two handles/tools so as to contort the geometry of the drum clamping ring and enable its removal/installation.

  19. Redox shuttles having an aromatic ring fused to a 1,1,4,4-tetrasubstituted cyclohexane ring

    DOE Patents [OSTI]

    Weng, Wei; Zhang, Zhengcheng; Amine, Khalil

    2015-12-01

    An electrolyte includes an alkali metal salt; an aprotic solvent; and a redox shuttle additive including an aromatic compound having at least one aromatic ring fused with at least one non-aromatic ring, the aromatic ring having two or more oxygen or phosphorus-containing substituents.

  20. Optical heterodyne detection for cavity ring-down spectroscopy

    DOE Patents [OSTI]

    Levenson, Marc D.; Paldus, Barbara A.; Zare, Richard N.

    2000-07-25

    A cavity ring-down system for performing cavity ring-down spectroscopy (CRDS) using optical heterodyne detection of a ring-down wave E.sub.RD during a ring-down phase or a ring-up wave E.sub.RU during a ring up phase. The system sends a local oscillator wave E.sub.LO and a signal wave E.sub.SIGNAL to the cavity, preferably a ring resonator, and derives an interference signal from the combined local oscillator wave E.sub.LO and the ring-down wave E.sub.RD (or ring-up wave E.sub.RU). The local oscillator wave E.sub.LO has a first polarization and the ring-down wave E.sub.RD has a second polarization different from the first polarization. The system has a combining arrangement for combining or overlapping local oscillator wave E.sub.LO and the ring-down wave E.sub.RD at a photodetector, which receives the interference signal and generates a heterodyne current I.sub.H therefrom. Frequency and phase differences between the waves are adjustable.

  1. Joining mechanism with stem tension and interlocked compression ring

    DOE Patents [OSTI]

    James, Allister W.; Morrison, Jay A.

    2012-09-04

    A stem (34) extends from a second part (30) through a hole (28) in a first part (22). A groove (38) around the stem provides a non-threaded contact surface (42) for a ring element (44) around the stem. The ring element exerts an inward force against the non-threaded contact surface at an angle that creates axial tension (T) in the stem, pulling the second part against the first part. The ring element is formed of a material that shrinks relative to the stem by sintering. The ring element may include a split collet (44C) that fits partly into the groove, and a compression ring (44E) around the collet. The non-threaded contact surface and a mating distal surface (48) of the ring element may have conic geometries (64). After shrinkage, the ring element is locked onto the stem.

  2. Collective accelerator using field-reversed plasma rings

    SciTech Connect (OSTI)

    Hartman, C.W.

    1981-09-19

    This note discusses the possibility of magnetically accelerating the plasma rings. At low-to-moderate ring kinetic energy, application to heating, fueling, and efficient current drive of conventional fusion reactors appears possible. At high ring kinetic energy, applications to inertial-confinement fusion through pellet heating and to transuranic element synthesis appear possible. The rings may be considered to be a self-linking flux bundle having net helicity. From an accelerator point of view, the rings represent collective particle entities held together by magnetic forces and may be viewed as macroparticles or micropellets having large magnetic moment per unit mass. Because of the relatively long lifetime and resiliency of the rings, it appears possible to accelerate to multimegajoule kinetic energy over reasonable distances and to focus the rings to centimeter-size dimensions.

  3. Mechanical seal having a double-tier mating ring

    DOE Patents [OSTI]

    Khonsari, Michael M.; Somanchi, Anoop K.

    2005-09-13

    An apparatus and method to enhance the overall performance of mechanical seals in one of the following ways: by reducing seal face wear, by reducing the contact surface temperature, or by increasing the life span of mechanical seals. The apparatus is a mechanical seal (e.g., single mechanical seals, double mechanical seals, tandem mechanical seals, bellows, pusher mechanical seals, and all types of rotating and reciprocating machines) comprising a rotating ring and a double-tier mating ring. In a preferred embodiment, the double-tier mating ring comprises a first and a second stationary ring that together form an agitation-inducing, guided flow channel to allow for the removal of heat generated at the seal face of the mating ring by channeling a coolant entering the mating ring to a position adjacent to and in close proximity with the interior surface area of the seal face of the mating ring.

  4. Self-seeding ring optical parametric oscillator

    DOE Patents [OSTI]

    Smith, Arlee V.; Armstrong, Darrell J.

    2005-12-27

    An optical parametric oscillator apparatus utilizing self-seeding with an external nanosecond-duration pump source to generate a seed pulse resulting in increased conversion efficiency. An optical parametric oscillator with a ring configuration are combined with a pump that injection seeds the optical parametric oscillator with a nanosecond duration, mJ pulse in the reverse direction as the main pulse. A retroreflecting means outside the cavity injects the seed pulse back into the cavity in the direction of the main pulse to seed the main pulse, resulting in higher conversion efficiency.

  5. On the evolution of vortex rings with swirl

    SciTech Connect (OSTI)

    Naitoh, Takashi, E-mail: naitoh.takashi@nitech.ac.jp [Department of Engineering Physics, Electronics and Mechanics, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Okura, Nobuyuki, E-mail: ohkura@meijo-u.ac.jp [Department of Vehicle and Mechanical Engineering, Meijo University, 1-501 Shiogamaguchi Tempaku-ku, Nagoya 468-8502 (Japan); Gotoh, Toshiyuki, E-mail: gotoh.toshiyuki@nitech.ac.jp [Department of Scientific and Engineering Simulation, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Kato, Yusuke [Controller Business Unit Engineering Division 1, Engineering Department 3, Denso Wave Incorporated, 1 Yoshiike Kusagi Agui-cho, Chita-gun Aichi 470-2297 (Japan)

    2014-06-15

    A laminar vortex ring with swirl, which has the meridional velocity component inside the vortex core, was experimentally generated by the brief fluid ejection from a rotating outlet. The evolution of the vortex ring was investigated with flow visualizations and particle image velocimetry measurements in order to find the influence of swirling flow in particular upon the transition to turbulence. Immediately after the formation of a vortex ring with swirl, a columnar strong vortex along the symmetric axis is observed in all cases of the present experiment. Then the characteristic fluid discharging from a vortex ring with swirl referred to as peeling off appears. The amount of discharging fluid due to the peeling off increases with the angular velocity of the rotating outlet. We conjectured that the mechanism generating the peeling off is related to the columnar strong vortex by close observations of the spatio-temporal development of the vorticity distribution and the cutting 3D images constructed from the successive cross sections of a vortex ring. While a laminar vortex ring without swirl may develop azimuthal waves around its circumference at some later time and the ring structure subsequently breaks, the swirling flow in a vortex ring core reduces the amplification rate of the azimuthal wavy deformation and preserved its ring structure. Then the traveling distance of a vortex ring can be extended using the swirl flow under certain conditions.

  6. STAR FORMATION IN NUCLEAR RINGS OF BARRED GALAXIES

    SciTech Connect (OSTI)

    Seo, Woo-Young; Kim, Woong-Tae E-mail: wkim@astro.snu.ac.kr

    2013-06-01

    Nuclear rings in barred galaxies are sites of active star formation. We use hydrodynamic simulations to study the temporal and spatial behavior of star formation occurring in nuclear rings of barred galaxies where radial gas inflows are triggered solely by a bar potential. The star formation recipes include a density threshold, an efficiency, conversion of gas to star particles, and delayed momentum feedback via supernova explosions. We find that the star formation rate (SFR) in a nuclear ring is roughly equal to the mass inflow rate to the ring, while it has a weak dependence on the total gas mass in the ring. The SFR typically exhibits a strong primary burst followed by weak secondary bursts before declining to very small values. The primary burst is associated with the rapid gas infall to the ring due to the bar growth, while the secondary bursts are caused by re-infall of the ejected gas from the primary burst. While star formation in observed rings persists episodically over a few Gyr, the duration of active star formation in our models lasts for only about half of the bar growth time, suggesting that the bar potential alone is unlikely to be responsible for gas supply to the rings. When the SFR is low, most star formation occurs at the contact points between the ring and the dust lanes, leading to an azimuthal age gradient of young star clusters. When the SFR is large, on the other hand, star formation is randomly distributed over the whole circumference of the ring, resulting in no apparent azimuthal age gradient. Since the ring shrinks in size with time, star clusters also exhibit a radial age gradient, with younger clusters found closer to the ring. The cluster mass function is well described by a power law, with a slope depending on the SFR. Giant gas clouds in the rings have supersonic internal velocity dispersions and are gravitationally bound.

  7. Microsoft PowerPoint - Salishan-04-06-Du

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

    1/2006 University of Minnesota Digital Technology Center Intelligent Storage Consortium 1 DISC University of Minnesota Digital Technology Center Intelligent Storage Consortium David DU Parallel Data Archive in HEC Environment Supported by Symantec, Sun Micro, LSI Logic Storage Systems, ETRE/Korea, ITRI/Taiwan DOE, ONR, Cisco, Intel 5/11/2006 University of Minnesota Digital Technology Center Intelligent Storage Consortium 2 Current Research Projects in DISC Parallel Archive in HEC Environment

  8. Margins for Profit, Not Error: Corporate Energy Management at DuPont

    SciTech Connect (OSTI)

    2010-06-25

    Alliance to Save Energy case study on corporate energy management at DuPont sponsored by the U.S. Department of Energy Industrial Technologies Program.

  9. DuPont's Journey to Build a Global Cellulosic BioFuel Business...

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

    ... All rights reserved 5 AG & NUTRITION INDUSTRIAL BIOSCIENCES ADVANCED ... All rights reserved DuPont Feedstock Collection Program: Contracting with more than 500 local farmers to ...

  10. Design Considerations for High Energy Electron -- Positron Storage Rings

    DOE R&D Accomplishments [OSTI]

    Richter, B.

    1966-11-01

    High energy electron-positron storage rings give a way of making a new attack on the most important problems of elementary particle physics. All of us who have worked in the storage ring field designing, building, or using storage rings know this. The importance of that part of storage ring work concerning tests of quantum electrodynamics and mu meson physics is also generally appreciated by the larger physics community. However, I do not think that most of the physicists working tin the elementary particle physics field realize the importance of the contribution that storage ring experiments can make to our understanding of the strongly interacting particles. I would therefore like to spend the next few minutes discussing the sort of things that one can do with storage rings in the strongly interacting particle field.

  11. Graphene Layer Growth: Collision of Migrating Five-MemberRings

    SciTech Connect (OSTI)

    Whitesides, Russell; Kollias, Alexander C.; Domin, Dominik; Lester Jr., William A.; Frenklach, Michael

    2005-12-02

    A reaction pathway is explored in which two cyclopenta groups combine on the zigzag edge of a graphene layer. The process is initiated by H addition to a five-membered ring, followed by opening of that ring and the formation of a six-membered ring adjacent to another five-membered ring. The elementary steps of the migration pathway are analyzed using density functional theory to examine the region of the potential energy surface associated with the pathway. The calculations are performed on a substrate modeled by the zigzag edge of tetracene. Based on the obtained energetics, the dynamics of the system are analyzed by solving the energy transfer master equations. The results indicate energetic and reaction-rate similarity between the cyclopenta combination and migration reactions. Also examined in the present study are desorption rates of migrating cyclopenta rings which are found to be comparable to cyclopenta ring migration.

  12. Graphene Layer Growth Chemistry: Five-Six-Ring Flip Reaction

    SciTech Connect (OSTI)

    Whitesides, R.; Domin, D.; Salomon-Ferrer, R.; Lester Jr., W.A.; Frenklach, M.

    2007-12-01

    Reaction pathways are presented for hydrogen-mediated isomerization of a five and six member carbon ring complex on the zigzag edge of a graphene layer. A new reaction sequence that reverses orientation of the ring complex, or 'flips' it, was identified. Competition between the flip reaction and 'ring separation' was examined. Ring separation is the reverse of the five and six member ring complex formation reaction, previously reported as 'ring collision'. The elementary steps of the pathways were analyzed using density-functional theory (DFT). Rate coefficients were obtained by solution of the energy master equation and classical transition state theory utilizing the DFT energies, frequencies, and geometries. The results indicate that the flip reaction pathway dominates the separation reaction and should be competitive with other pathways important to the graphene zigzag edge growth in high temperature environments.

  13. Rotary Firing in Ring-Shaped Protein Explains Unidirectionality

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

    Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Wednesday, 28 April 2010 00:00 Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded

  14. Ring Cycle for Dilating and Constricting the Nuclear Pore

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

    Ring Cycle for Dilating and Constricting the Nuclear Pore Ring Cycle for Dilating and Constricting the Nuclear Pore Print Thursday, 13 June 2013 09:30 Pictured is an illustration of several nuclear pore complexes (NPCs) embedded in a cell nucleus. NPCs act as gatekeepers between a cell's cytoplasm and its nucleus. Based on crystallographic analyses, Sozanne R. Solmaz et al. uncover the molecular mechanism that underlies the large changes in diameter of NPCs and suggest a "ring cycle"

  15. Reversible Seeding in Storage Rings (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    We propose to generate steady-state microbunching in a storage ring with a reversible seeding scheme. High gain harmonic generation (HGHG) and echo-enabled harmonic generation ...

  16. Rotary Firing in Ring-Shaped Protein Explains Unidirectionality

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

    Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on...

  17. A Shallow Attenuating Anomaly Inside The Ring Fracture Of The...

    Open Energy Info (EERE)

    Roberts,Keiiti Aki,Michael C. Fehler. 1995. A Shallow Attenuating Anomaly Inside The Ring Fracture Of The Valles Caldera, New Mexico. Journal of Volcanology and Geothermal...

  18. Used Fuel Disposition Campaign Phase I Ring Compression Testing...

    Energy Savers [EERE]

    Phase I Ring Compression Testing of High Burnup Cladding Used Fuel Disposition Campaign ... of the technical basis for extended storage and transportation of high-burnup fuel. ...

  19. A Compact Ring Design with Tunable Momentum Compaction

    SciTech Connect (OSTI)

    Sun, Y.; ,

    2012-05-17

    A storage ring with tunable momentum compaction has the advantage in achieving different RMS bunch length with similar RF capacity, which is potentially useful for many applications, such as linear collider damping ring and predamping ring where injected beam has a large energy spread and a large transverse emittance. A tunable bunch length also makes the commissioning and fine tuning easier in manipulating the single bunch instabilities. In this paper, a compact ring design based on a supercell is presented, which achieves a tunable momentum compaction while maintaining a large dynamic aperture.

  20. First Magnet Girder Installed in NSLS-II Storage Ring

    ScienceCinema (OSTI)

    Frank Lincoln

    2013-07-19

    Supervisor Frank Lincoln explains how the first magnet girder is installed in the storage ring of Brookhaven National Laboratory's National Synchrotron Light Source II (NSLS-II).

  1. Vertical Emmittance Studies at the ATF Damping Ring (Technical...

    Office of Scientific and Technical Information (OSTI)

    Visit OSTI to utilize additional information resources in energy science and technology. A ... A primary purpose of the ATF Damping Ring is to demonstrate the small vertical emittance ...

  2. Exploration of the Versatility of Ring Opening Metathesis Polymerizati...

    Office of Scientific and Technical Information (OSTI)

    of Ring Opening Metathesis Polymerization: an Approach for Gaining Access to Low Density Polymeric Aerogels Citation Details In-Document Search Title: Exploration of the...

  3. The Phylogenetic Signature Underlying ATP Synthase c-Ring Compliance

    SciTech Connect (OSTI)

    Pandini, Alessandro; Kleinjung, Jens; Taylor, Willie R.; Junge, Wolfgang; Khan, Shahid

    2015-09-01

    The proton-driven ATP synthase (FOF1) is comprised of two rotary, stepping motors (FO and F1) coupled by an elastic power transmission. The elastic compliance resides in the rotor module that includes the membrane-embedded FO c-ring. Proton transport by FO is firmly coupled to the rotation of the c-ring relative to other FO subunits (ab2). It drives ATP synthesis. We used a computational method to investigate the contribution of the c-ring to the total elastic compliance. We performed principal component analysis of conformational ensembles built using distance constraints from the bovine mitochondrial c-ring x-ray structure. Angular rotary twist, the dominant ring motion, was estimated to show that the c-ring accounted in part for the measured compliance. Ring rotation was entrained to rotation of the external helix within each hairpin-shaped c-subunit in the ring. Ensembles of monomer and dimers extracted from complete c-rings showed that the coupling between collective ring and the individual subunit motions was independent of the size of the c-ring, which varies between organisms. Molecular determinants were identified by covariance analysis of residue coevolution and structural-alphabet-based local dynamics correlations. The residue coevolution gave a readout of subunit architecture. The dynamic couplings revealed that the hinge for both ring and subunit helix rotations was constructed from the proton-binding site and the adjacent glycine motif (IB-GGGG) in the midmembrane plane. IB-GGGG motifs were linked by long-range couplings across the ring, while intrasubunit couplings connected the motif to the conserved cytoplasmic loop and adjacent segments. The correlation with principal collective motions shows that the couplings underlie both ring rotary and bending motions. Noncontact couplings between IB-GGGG motifs matched the coevolution signal as well as contact couplings

  4. Non-destructive analysis of DU content in the NIF hohlraums

    SciTech Connect (OSTI)

    Gharibyan, Narek; Moody, Ken J.; Shaughnessy, Dawn A.

    2015-12-16

    The advantage of using depleted uranium (DU) hohlraums in high-yield deuterium-tritium (DT) shots at the National Ignition Facility (NIF) is addressed by Döppner, et al., in great detail [1]. This DU based hohlraum incorporates a thin layer of DU, ~7 μm thick, on the inner surface along with a thin layer of a gold coating, ~0.7 μm thick, while the outer layer is ~22 μm thick gold. A thickness measurement of the DU layer can be performed using an optical microscope where the total DU weight can be computed provided a uniform DU layer. However, the uniformity of the thickness is not constant throughout the hohlraum since CAD drawing calculations of the DU weight do not agree with the computed values from optical measurements [2]. Therefore, a non-destructive method for quantifying the DU content in hohlraums has been established by utilizing gamma-ray spectroscopy. The details of this method, along with results from several hohlraums, are presented in this report.

  5. The Phylogenetic Signature Underlying ATP Synthase c-Ring Compliance

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

    Pandini, Alessandro; Kleinjung, Jens; Taylor, Willie R.; Junge, Wolfgang; Khan, Shahid

    2015-09-01

    The proton-driven ATP synthase (FOF1) is comprised of two rotary, stepping motors (FO and F1) coupled by an elastic power transmission. The elastic compliance resides in the rotor module that includes the membrane-embedded FO c-ring. Proton transport by FO is firmly coupled to the rotation of the c-ring relative to other FO subunits (ab2). It drives ATP synthesis. We used a computational method to investigate the contribution of the c-ring to the total elastic compliance. We performed principal component analysis of conformational ensembles built using distance constraints from the bovine mitochondrial c-ring x-ray structure. Angular rotary twist, the dominant ringmore » motion, was estimated to show that the c-ring accounted in part for the measured compliance. Ring rotation was entrained to rotation of the external helix within each hairpin-shaped c-subunit in the ring. Ensembles of monomer and dimers extracted from complete c-rings showed that the coupling between collective ring and the individual subunit motions was independent of the size of the c-ring, which varies between organisms. Molecular determinants were identified by covariance analysis of residue coevolution and structural-alphabet-based local dynamics correlations. The residue coevolution gave a readout of subunit architecture. The dynamic couplings revealed that the hinge for both ring and subunit helix rotations was constructed from the proton-binding site and the adjacent glycine motif (IB-GGGG) in the midmembrane plane. IB-GGGG motifs were linked by long-range couplings across the ring, while intrasubunit couplings connected the motif to the conserved cytoplasmic loop and adjacent segments. The correlation with principal collective motions shows that the couplings underlie both ring rotary and bending motions. Noncontact couplings between IB-GGGG motifs matched the coevolution signal as well as contact couplings. The residue coevolution reflects the physiological importance of the dynamics

  6. Origin and dynamics of vortex rings in drop splashing

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

    Lee, Ji San; Park, Su Ji; Lee, Jun Ho; Weon, Byung Mook; Fezzaa, Kamel; Je, Jung Ho

    2015-09-04

    A vortex is a flow phenomenon that is very commonly observed in nature. More than a century, a vortex ring that forms during drop splashing has caught the attention of many scientists due to its importance in understanding fluid mixing and mass transport processes. However, the origin of the vortices and their dynamics remain unclear, mostly due to the lack of appropriate visualization methods. Here, with ultrafast X-ray phase-contrast imaging, we show that the formation of vortex rings originates from the energy transfer by capillary waves generated at the moment of the drop impact. Interestingly, we find a row ofmore » vortex rings along the drop wall, as demonstrated by a phase diagram established here, with different power-law dependencies of the angular velocities on the Reynolds number. These results provide important insight that allows understanding and modelling any type of vortex rings in nature, beyond just vortex rings during drop splashing.« less

  7. Origin and dynamics of vortex rings in drop splashing

    SciTech Connect (OSTI)

    Lee, Ji San; Park, Su Ji; Lee, Jun Ho; Weon, Byung Mook; Fezzaa, Kamel; Je, Jung Ho

    2015-09-04

    A vortex is a flow phenomenon that is very commonly observed in nature. More than a century, a vortex ring that forms during drop splashing has caught the attention of many scientists due to its importance in understanding fluid mixing and mass transport processes. However, the origin of the vortices and their dynamics remain unclear, mostly due to the lack of appropriate visualization methods. Here, with ultrafast X-ray phase-contrast imaging, we show that the formation of vortex rings originates from the energy transfer by capillary waves generated at the moment of the drop impact. Interestingly, we find a row of vortex rings along the drop wall, as demonstrated by a phase diagram established here, with different power-law dependencies of the angular velocities on the Reynolds number. These results provide important insight that allows understanding and modelling any type of vortex rings in nature, beyond just vortex rings during drop splashing.

  8. Stabilization of ring dark solitons in Bose-Einstein condensates

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

    Wang, Wenlong; Kevrekidis, P. G.; Carretero-González, R.; Frantzeskakis, D. J.; Kaper, Tasso J.; Ma, Manjun

    2015-09-14

    Earlier work has shown that ring dark solitons in two-dimensional Bose-Einstein condensates are generically unstable. In this work, we propose a way of stabilizing the ring dark soliton via a radial Gaussian external potential. We investigate the existence and stability of the ring dark soliton upon variations of the chemical potential and also of the strength of the radial potential. Numerical results show that the ring dark soliton can be stabilized in a suitable interval of external potential strengths and chemical potentials. Furthermore, we also explore different proposed particle pictures considering the ring as a moving particle and find, wheremore » appropriate, results in very good qualitative and also reasonable quantitative agreement with the numerical findings.« less

  9. Stabilization of ring dark solitons in Bose-Einstein condensates

    SciTech Connect (OSTI)

    Wang, Wenlong; Kevrekidis, P. G.; Carretero-González, R.; Frantzeskakis, D. J.; Kaper, Tasso J.; Ma, Manjun

    2015-09-14

    Earlier work has shown that ring dark solitons in two-dimensional Bose-Einstein condensates are generically unstable. In this work, we propose a way of stabilizing the ring dark soliton via a radial Gaussian external potential. We investigate the existence and stability of the ring dark soliton upon variations of the chemical potential and also of the strength of the radial potential. Numerical results show that the ring dark soliton can be stabilized in a suitable interval of external potential strengths and chemical potentials. Furthermore, we also explore different proposed particle pictures considering the ring as a moving particle and find, where appropriate, results in very good qualitative and also reasonable quantitative agreement with the numerical findings.

  10. E. 1. DU PONT DE NEMOURS & COMPANY

    Office of Legacy Management (LM)

    E. 1. DU PONT DE NEMOURS & COMPANY ,*Eo~UI~ WILMINGTON 99, DELAWARE IQ?. R. L. Kilburn, Director (2) Technical and Production Division Savannah River Operations Office U. S. Atomic Energy Commission -:; ;:~~~~!,~:c';~,~"s-,fi,:-~~~i:~!~~,,,,~~, ,';;'nf;;G;h=;cr;lina :J "'- I Dear IfI. Kilburn: RESEARCH PROGRAMS IN SUPPORT OF SAVANNAH RIVER In a letter to you dated April 19, 1956, ~~14-56-218, we recommended that the Savannah River Operations Office set aside funds to cover certain

  11. Springback Prediction on Slit-Ring Test

    SciTech Connect (OSTI)

    Chen Xiaoming; Shi, Ming F.; Ren Feng; Xia, Z. Cedric

    2005-08-05

    Advanced high strength steels (AHSS) are increasingly being used in the automotive industry to reduce vehicle weight while improving vehicle crash performance. One of the concerns in manufacturing is springback control after stamping. Although computer simulation technologies have been successfully applied to predict stamping formability, they still face major challenges in springback prediction, particularly for AHSS. Springback analysis is very complicated and involves large deformation problems in the forming stage and mechanical multiplying effect during the elastic recovery after releasing a part from the die. Therefore, the predictions are very sensitive to the simulation parameters used. It is very critical in springback simulation to choose an appropriate material model, element formulation and contact algorithm. In this study, a springback benchmark test, the slit ring cup, is used in the springback simulation with commercially available finite element analysis (FEA) software, LS-DYNA. The sensitivity of seven simulation variables on springback predictions was investigated, and a set of parameters with stable simulation results was identified. Final simulations using the selected set of parameters were conducted on six different materials including two AHSS steels, two conventional high strength steels, one mild steel and an aluminum alloy. The simulation results are compared with experimental measurements for all six materials and a favorable result is achieved. Simulation errors as compared against test results falls within 10%.

  12. DETECTION OF LOW-VELOCITY COLLISIONS IN SATURN'S F RING

    SciTech Connect (OSTI)

    Attree, N. O.; Murray, C. D.; Cooper, N. J.; Williams, G. A.

    2012-08-20

    Jets of material extending several hundred kilometers from Saturn's F ring are thought to be caused by collisions at speeds of several tens of ms{sup -1} between {approx}10 km diameter objects such as S/2004 S 6 and the core of the ring. The subsequent effects of Keplerian shear give rise to the multi-stranded nature of the F ring. Observations of the ring by the Imaging Science Subsystem experiment on the Cassini spacecraft have provided evidence that some smaller protrusions from the ring's core are the result of low-velocity collisions with nearby objects. We refer to these protrusions as 'mini-jets' and one such feature has been observed for {approx}7.5 hr as its length changed from {approx}75 km to {approx}250 km while it simultaneously appeared to collapse into the core. Orbit determinations suggest that such mini-jets consist of ring material displaced by a {approx}1 ms{sup -1} collision with a nearby moonlet, resulting in paths relative to the core that are due to a combination of Keplerian shear and epicyclic motion. Detections of mini-jets in the Cassini images suggest that it may now be possible to understand most small-scale F ring structure as the result of such collisions. A study of these mini-jets will therefore put constraints on the properties of the colliding population as well as improve our understanding of low-velocity collisions between icy objects.

  13. AROUND THE RING WE GO: THE COLD, DENSE RING OF MOLECULAR GAS IN NGC 1614

    SciTech Connect (OSTI)

    Sliwa, Kazimierz; Wilson, Christine D.; Iono, Daisuke; Peck, Alison; Matsushita, Satoki E-mail: wilson@physics.mcmaster.ca E-mail: apeck@alma.cl

    2014-11-20

    We present high-resolution archival Atacama Large Millimeter/submillimeter Array (ALMA) {sup 12}CO J = 3-2 and J = 6-5 and HCO{sup +} J = 4-3 observations and new CARMA {sup 12}CO and {sup 13}CO J = 1-0 observations of the luminous infrared galaxy NGC 1614. The high-resolution maps show the previously identified ring-like structure while the {sup 12}CO J = 3-2 map shows extended emission that traces the extended dusty features. We combined these new observations with previously published Submillimeter Array {sup 12}CO and {sup 13}CO J = 2-1 observations to constrain the physical conditions of the molecular gas at a resolution of 230 pc using a radiative transfer code and a Bayesian likelihood analysis. At several positions around the central ring-like structure, the molecular gas is cold (20-40 K) and dense (>10{sup 3.0} cm{sup –3}). The only region that shows evidence of a second molecular gas component is the ''hole'' in the ring. The {sup 12}CO-to-{sup 13}CO abundance ratio is found to be greater than 130, more than twice the local interstellar medium value. We also measure the CO-to-H{sub 2} conversion factor, α{sub CO}, to range from 0.9 to 1.5 M {sub ☉} (K km s{sup –1} pc{sup 2}){sup –1}.

  14. RingCentral User Guide | Department of Energy

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

    User Guide RingCentral User Guide This is the guide on the use of DOE's Personnel Accountability phone service called RingCentral. RingCentral User Guide (4.75 MB) Responsible Contacts Bruce Murray HR Policy Advisor E-mail bruce.murray@hq.doe.gov Phone 202-586-3372 More Documents & Publications US Department of Energy Office of the Chief Information Officer Nortel CallPilot A-Style Command Comparison Card NTER Authoring Training Participant_Guide_2012

  15. Porous silicon ring resonator for compact, high sensitivity biosensing applications

    SciTech Connect (OSTI)

    Rodriguez, Gilberto A.; Hu, Shuren; Weiss, Sharon M.

    2015-01-01

    A ring resonator is patterned on a porous silicon slab waveguide to produce a compact, high quality factor biosensor with a large internal surface area available for enhanced recognition of biological and chemical molecules. The porous nature of the ring resonator allows molecules to directly interact with the guided mode. Quality factors near 10,000 were measured for porous silicon ring resonators with a radius of 25 ?m. A bulk detection sensitivity of 380 nm/RIU was measured upon exposure to salt water solutions. Specific detection of nucleic acid molecules was demonstrated with a surface detection sensitivity of 4 pm/nM.

  16. Porous silicon ring resonator for compact, high sensitivity biosensing applications

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

    Rodriguez, Gilberto A.; Hu, Shuren; Weiss, Sharon M.

    2015-01-01

    A ring resonator is patterned on a porous silicon slab waveguide to produce a compact, high quality factor biosensor with a large internal surface area available for enhanced recognition of biological and chemical molecules. The porous nature of the ring resonator allows molecules to directly interact with the guided mode. Quality factors near 10,000 were measured for porous silicon ring resonators with a radius of 25 μm. A bulk detection sensitivity of 380 nm/RIU was measured upon exposure to salt water solutions. Specific detection of nucleic acid molecules was demonstrated with a surface detection sensitivity of 4 pm/nM.

  17. Damping Ring R&D at CESR-TA

    SciTech Connect (OSTI)

    Rubin, David

    2015-01-23

    Accelerators that collide high energy beams of matter and anti-matter are essential tools for the investigation of the fundamental constituents of matter, and the search for new forms of matter and energy. A “Linear Collider” is a machine that would bring high energy and very compact bunches of electrons and positrons (anti-electrons) into head-on collision. Such a machine would produce (among many other things) the newly discovered Higgs particle, enabling a detailed study of its properties. Among the most critical and challenging components of a linear collider are the damping rings that produce the very compact and intense beams of electrons and positrons that are to be accelerated into collision. Hot dilute particle beams are injected into the damping rings, where they are compressed and cooled. The size of the positron beam must be reduced more than a thousand fold in the damping ring, and this compression must be accomplished in a fraction of a second. The cold compact beams are then extracted from the damping ring and accelerated into collision at high energy. The proposed International Linear Collider (ILC), would require damping rings that routinely produce such cold, compact and intense beams. The goal of the Cornell study was a credible design for the damping rings for the ILC. Among the technical challenges of the damping rings; the development of instrumentation that can measure the properties of the very small beams in a very narrow window of time, and mitigation of the forces that can destabilize the beams and prevent adequate cooling, or worse lead to beam loss. One of the most pernicious destabilizing forces is due to the formation of clouds of electrons in the beam pipe. The electron cloud effect is a phenomenon in particle accelerators in which a high density of low energy electrons, build up inside the vacuum chamber. At the outset of the study, it was anticipated that electron cloud effects would limit the intensity of the positron ring

  18. An accumulator/compressor ring for Ne+ ions (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    An accumulatorcompressor ring for Ne+ ions Citation Details In-Document Search Title: An accumulatorcompressor ring for Ne+ ions The primary goal of the High Energy Density ...

  19. Closing the gap: DuPont`s response to the 1991 industrial power benchmarking study

    SciTech Connect (OSTI)

    Bailey, W.F.

    1996-12-31

    In 1991, DuPont benchmarked its industrial power facilities against other industrial and independent power producers, identified key areas of weakness and developed a blueprint for change to improve its energy competitiveness. Since then, efforts have been undertaken to address the weaknesses identified in the benchmarking study and to capitalize on strengths in DuPont`s various industrial power operations. This paper provides an update to the DuPont Industrial Power Benchmarking Study and describes major focus areas such as competitive electricity sourcing, control technology, performance assessment tools and internal networking efforts.

  20. Neutral and positively charged excitons in narrow quantum ring

    SciTech Connect (OSTI)

    Porras Monroy, L. C.; Rodrguez-Prada, F. A.; Mikhailov, I. D.

    2014-05-15

    We study theoretically quantized states of a neutral and a positively charged exciton (trion X{sup +}) confined in a heterostructure with the ring-like geometry. In order to assess the experimentally relevant domain of parameters, we adopt a simple model of a narrow ring when 3D wave equations for the neutral and positively charged excitons can be separated. By using the Fourier series method, we have calculated the energy spectra of excitons complexes in a quantum ring as a function of the electron-to-hole mass ratio, the ring radius, and the magnetic field strength. The quantum-size effect and the size-dependent magnetic oscillations of energy levels of excitons' complexes spectra have been revealed.

  1. Structural and functional analysis of Nup120 suggests ring formation...

    Office of Scientific and Technical Information (OSTI)

    Title: Structural and functional analysis of Nup120 suggests ring formation of the Nup84 complex Authors: Seo, Hyuk-Soo ; Ma, Yingli ; Debler, Erik W. ; Wacker, Daniel ; Kutik, ...

  2. Progress Report on the g-2 Storage Ring Magnet System

    SciTech Connect (OSTI)

    Bunce, G.A.; Cullen, J.; Danby, G.; Green, M.A.; Jackson, J.; Jia, L.; Krienen, F.; Meier, R.; Meng, W.; Morse, W.; Pai, C.; Polk, I.; Prodell, A.; Shutt, R.; Snydstrup, L.; Yamamoto, A.

    1995-06-01

    The 3.1 GeV muon storage ring for the g-2 experiment at Brookhaven National Laboratory has three large solenoid magnets that form a continuous 1.451 tesla storage ring dipole with an average beam bend radius of 7.1 meters. In addition to the three storage ring solenoids, there is an inflector dipole with nested dipole coils that create very little stray magnetic field. A superconducting shield on the inflector gets rid of most of the remaining stray flux. This paper reports on the progress made on the storage ring solenoid magnet system and the inflector as of June 1995. The results of cryogenic system tests are briefly reported.

  3. Fermilab Muon Ring Arrives to a Large Crowd of Fans

    SciTech Connect (OSTI)

    2013-08-15

    A very large group of people gathered to watch the muon g-2 ring on its last leg of the big move from Brookhaven National Laboratory in Long Island, NY to Fermilab in Batavia, IL.

  4. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

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

    Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported...

  5. Single-Particle Dynamics in Electron Storage Rings with Extremely...

    Office of Scientific and Technical Information (OSTI)

    we have refined transfer maps of common elements in storage rings and developed a new method to compute the resonance driving terms as they are built up along a beamline....

  6. Correlations Between Metallic Lubricant Additive Species in the Ring Pack

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

    and Ash Emissions and Their Dependence on Crankcase Oil Properties | Department of Energy Correlations Between Metallic Lubricant Additive Species in the Ring Pack and Ash Emissions and Their Dependence on Crankcase Oil Properties Correlations Between Metallic Lubricant Additive Species in the Ring Pack and Ash Emissions and Their Dependence on Crankcase Oil Properties Presentation given at DEER 2006, August 20-24, 2006, Detroit, Michigan. Sponsored by the U.S. DOE's EERE FreedomCar and Fuel

  7. Rotary Firing in Ring-Shaped Protein Explains Unidirectionality

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

    Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand

  8. Rotary Firing in Ring-Shaped Protein Explains Unidirectionality

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

    Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand

  9. Rotary Firing in Ring-Shaped Protein Explains Unidirectionality

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

    Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand

  10. Rotary Firing in Ring-Shaped Protein Explains Unidirectionality

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

    Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand

  11. Rotary Firing in Ring-Shaped Protein Explains Unidirectionality

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

    Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand

  12. Single-ring magnetic cusp low gas pressure ion source

    DOE Patents [OSTI]

    Bacon, Frank M.; Brainard, John P.; O'Hagan, James B.; Walko, Robert J.

    1985-01-01

    A single-ring magnetic cusp low gas pressure ion source designed for use in a sealed, nonpumped neutron generator utilizes a cathode and an anode, three electrically floating electrodes (a reflector behind the cathode, a heat shield around the anode, and an aperture plate), together with a single ring-cusp magnetic field, to establish and energy-filtering mechanism for producing atomic-hydrogen ions.

  13. Rotary Firing in Ring-Shaped Protein Explains Unidirectionality

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

    Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand

  14. Rotary Firing in Ring-Shaped Protein Explains Unidirectionality

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

    Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand

  15. From Protein Structure to Function: Ring Cycle for Dilating and

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

    Constricting the Nuclear Pore From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore Print Wednesday, 28 August 2013 00:00 Nuclear pore complexes (NPCs) act as the central gatekeepers for selective transport between the cytoplasm and the nucleus. They allow the exchange of selected proteins and ribonucleoproteins, while preventing the transport of material not

  16. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

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

    Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Monday, 28 November 2011 14:52 Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin

  17. Coupled beam motion in a storage ring with crab cavities

    SciTech Connect (OSTI)

    Huang, Xiaobiao

    2015-11-16

    We studied the coupled beam motion in a storage ring between the transverse and longitudinal directions introduced by crab cavities. Analytic form of the linear decoupling transformation is derived. Also, the equilibrium bunch distribution in an electron storage ring with a crab cavity is given, including contribution to the eigen-emittance induced by the crab cavity. Application to the short pulse generation scheme using crab cavities [1] is considered.

  18. Nondestructive Testing Qualification of Main Circulatory Tube Pipes DU 500

    SciTech Connect (OSTI)

    Tabakova, Bojana M.; Tzokov, Petio

    2004-07-01

    The criteria for safe operation of nuclear energetic installations is given a higher priority in the policy of Kozloduy Nuclear Power Plant. An efficient non-destructive inspection is the key point for the safe service. Kozloduy NPP keeps on making investments in equipment and qualification of specialists in this field. The processes of qualification of the NDT components, important for the nuclear and radiation safety, make considerable improvement in Kozloduy NPP, thanks to the accumulated in the years experience in the activities of NDT inspection qualification, and to the help of our partners Serco Assurance and the Institute of Rzes. The results obtained by ultrasonic non-destructive inspection of circulation tube mains DU 500 WWER 440 type are under discussion in this report. (authors)

  19. Energy Secretary Chu to Tour DuPont Clean Energy Innovation Facilities

    Broader source: Energy.gov [DOE]

    WASHINGTON – Tomorrow, Wednesday, May 23, 2012, U.S. Energy Secretary Steven Chu will visit DuPont in Wilmington, Delaware, where he will tour the company’s clean energy research and development...

  20. Mechanical seal having a single-piece, perforated mating ring

    DOE Patents [OSTI]

    Khonsari, Michael M.; Somanchi, Anoop K.

    2007-08-07

    A mechanical seal (e.g., single mechanical seals, double mechanical seals, tandem mechanical seals, bellows, pusher mechanical seals, and all types of rotating and reciprocating machines) with reduced contact surface temperature, reduced contact surface wear, or increased life span. The mechanical seal comprises a rotating ring and a single-piece, perforated mating ring, which improves heat transfer by controllably channeling coolant flow through the single-piece mating ring such that the coolant is in substantially uniform thermal contact with a substantial portion of the interior surface area of the seal face, while maintaining the structural integrity of the mechanical seal and minimizing the potential for coolant flow interruptions to the seal face caused by debris or contaminants (e.g., small solids and trash) in the coolant.

  1. Exploring overstabilities in Saturn's a ring using two stellar occultations

    SciTech Connect (OSTI)

    Hedman, M. M.; Nicholson, P. D.; Salo, H.

    2014-07-01

    Certain regions of Saturn's rings exhibit periodic opacity variations with characteristic radial wavelengths of up to a few hundred meters that have been attributed to viscous overstabilities. The Visual and Infrared Mapping Spectrometer on board the Cassini spacecraft observed two stellar occultations of the star γ Crucis that had sufficient resolution to discern a subset of these periodic patterns in a portion of the A ring between 124,000 and 125,000 km from Saturn's center. These data reveal that the wavelengths and intensities of the patterns vary systematically across this region, but that these parameters are not strictly determined by the ring's average optical depth. Furthermore, our observations indicate that these opacity variations have an azimuthal coherence scale of around 3000 km.

  2. Rf System Requirements for JLabs MEIC Collider Ring

    SciTech Connect (OSTI)

    Wang, Shaoheng; Li, Rui; Rimmer, Robert A.; Wang, Haipeng; Zhang, Yuhong

    2013-06-01

    The Medium-energy Electron Ion Collider (MEIC), proposed by Jefferson Lab, consists of a series of accelerators. At the top energy are the electron and ion collider rings. For the ion ring, it accelerates five long ion bunches to colliding energy and rebunches ions into a train of very short bunches before colliding. A set of low frequency RF system is needed for the long ion bunch energy ramping. Another set of high frequency RF cavities is needed to rebunch ions. For the electron ring, superconducting RF (SRF) cavities are needed to compensate the synchrotron radiation energy loss. The impedance of the SRF cavities must be low enough to keep the high current electron beam stable. The preliminary design requirements of these RF cavities are presented.

  3. DEVELOPMENT OF TITANIUM NITRIDE COATING FOR SNS RING VACUUM CHAMBERS.

    SciTech Connect (OSTI)

    HE,P.; HSEUH,H.C.; MAPES,M.; TODD,R.; WEISS,D.

    2001-06-18

    The inner surface of the ring vacuum chambers of the US Spallation Neutron Source (SNS) will be coated with {approximately}100 nm of Titanium Nitride (TiN). This is to minimize the secondary electron yield (SEY) from the chamber wall, and thus avoid the so-called e-p instability caused by electron multipacting as observed in a few high-intensity proton storage rings. Both DC sputtering and DC-magnetron sputtering were conducted in a test chamber of relevant geometry to SNS ring vacuum chambers. Auger Electron Spectroscopy (AES) and Rutherford Back Scattering (RBS) were used to analyze the coatings for thickness, stoichiometry and impurity. Excellent results were obtained with magnetron sputtering. The development of the parameters for the coating process and the surface analysis results are presented.

  4. Magnetic edge states in Aharonov-Bohm graphene quantum rings

    SciTech Connect (OSTI)

    Farghadan, R., E-mail: rfarghadan@kashanu.ac.ir; Heidari Semiromi, E. [Department of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Saffarzadeh, A. [Department of Physics, Payame Noor University, P.O. Box 19395-3697 Tehran (Iran, Islamic Republic of); Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6 (Canada)

    2013-12-07

    The effect of electron-electron interaction on the electronic structure of Aharonov-Bohm (AB) graphene quantum rings (GQRs) is explored theoretically using the single-band tight-binding Hamiltonian and the mean-field Hubbard model. The electronic states and magnetic properties of hexagonal, triangular, and circular GQRs with different sizes and zigzag edge terminations are studied. The results show that, although the AB oscillations in the all types of nanoring are affected by the interaction, the spin splitting in the AB oscillations strongly depends on the geometry and the size of graphene nanorings. We found that the total spin of hexagonal and circular rings is zero and therefore, no spin splitting can be observed in the AB oscillations. However, the non-zero magnetization of the triangular rings breaks the degeneracy between spin-up and spin-down electrons, which produces spin-polarized AB oscillations.

  5. Note: O-ring stack system for electron gun alignment

    SciTech Connect (OSTI)

    Park, In-Yong; Cho, Boklae; Han, Cheolsu; Shin, Seungmin; Lee, Dongjun; Ahn, Sang Jung

    2015-01-15

    We present a reliable method for aligning an electron gun which consists of an electron source and lenses by controlling a stack of rubber O-rings in a vacuum condition. The beam direction angle is precisely tilted along two axes by adjusting the height difference of a stack of O-rings. In addition, the source position is shifted in each of three orthogonal directions. We show that the tilting angle and linear shift along the x and y axes as obtained from ten stacked O-rings are ±2.55° and ±2 mm, respectively. This study can easily be adapted to charged particle gun alignment and adjustments of the flange position in a vacuum, ensuring that its results can be useful with regard to electrical insulation between flanges with slight modifications.

  6. Combination ring cavity and backward Raman waveguide amplifier

    DOE Patents [OSTI]

    Kurnit, Norman A.

    1983-01-01

    A combination regenerative ring and backward Raman waveguide amplifier and a combination regenerative ring oscillator and backward Raman waveguide amplifier which produce Raman amplification, pulse compression, and efficient energy extraction from the CO.sub.2 laser pump signal for conversion into a Stokes radiation signal. The ring cavity configuration allows the CO.sub.2 laser pump signal and Stokes signal to copropagate through the Raman waveguide amplifier. The backward Raman waveguide amplifier configuration extracts a major portion of the remaining energy from the CO.sub.2 laser pump signal for conversion to Stokes radiation. Additionally, the backward Raman amplifier configuration produces a Stokes radiation signal which has a high intensity and a short duration. Adjustment of the position of overlap of the Stokes signal and the CO.sub.2 laser pump signal in the backward Raman waveguide amplifiers alters the amount of pulse compression which can be achieved.

  7. Update on the MEIC electron collider ring design

    SciTech Connect (OSTI)

    Lin, Fangei; Derbenev, Yaroslav S.; Harwood, Leigh; Hutton, Andrew; Morozov, Vasiliy; Pilat, Fulvia; Zhang, Yuhong; Cai, Y.; Nosochkov, Y. M.; Sullivan, Michael; Wang, M.-H; Wienands, Uli

    2015-09-01

    The electron collider ring of the Medium-energy Electron-Ion Collider (MEIC) at Jefferson Lab is designed to accumulate and store a high-current polarized electron beam for collisions with an ion beam. We consider a design of the electron collider ring based on reusing PEP-II components, such as magnets, power supplies, vacuum system, etc. This has the potential to significantly reduce the cost and engineering effort needed to bring the project to fruition. This paper reports on an electron ring optics design considering the balance of PEP-II hardware parameters (such as dipole sagitta, magnet field strengths and acceptable synchrotron radiation power) and electron beam quality in terms of equilibrium emittances.

  8. Update on the MEIC electron collider ring design

    SciTech Connect (OSTI)

    Lin, F.; Derbenev, Ya. S.; Harwood, L.; Hutton, A.; Morozov, V. S.; Pilat, F.; Zhang, Y.; Cai, Y.; Nosochkov, Y. M.; Sullivan, M.; Wang, M-H; Wienands, U.

    2015-07-14

    The electron collider ring of the Medium-energy Electron-Ion Collider (MEIC) at Jefferson Lab is designed to accumulate and store a high-current polarized electron beam for collisions with an ion beam. We consider a design of the electron collider ring based on reusing PEPII components, such as magnets, power supplies, vacuum system, etc. This has the potential to significantly reduce the cost and engineering effort needed to bring the project to fruition. This paper reports on an electron ring optics design considering the balance of PEP-II hardware parameters (such as dipole sagitta, magnet field strengths and acceptable synchrotron radiation power) and electron beam quality in terms of equilibrium emittances.

  9. DESIGN OF VISIBLE DIAGNOSTIC BEAMLINE FOR NSLS2 STORAGE RING

    SciTech Connect (OSTI)

    Cheng, W.; Fernandes, H.; Hseuh, H.; Kosciuk, B.; Krinsky, S.; Singh, O.

    2011-03-28

    A visible synchrotron light monitor (SLM) beam line has been designed at the NSLS2 storage ring, using the bending magnet radiation. A retractable thin absorber will be placed in front of the first mirror to block the central x-rays. The first mirror will reflect the visible light through a vacuum window. The light is guided by three 6-inch diameter mirrors into the experiment hutch. In this paper, we will describe design work on various optical components in the beamline. The ultra high brightness NSLS-II storage ring is under construction at Brookhaven National Laboratory. It will have 3GeV, 500mA electron beam circulating in the 792m ring, with very low emittance (0.9nm.rad horizontal and 8pm.rad vertical). The ring is composed of 30 DBA cells with 15 fold symmetry. Three damping wigglers will be installed in long straight sections 8, 18 and 28 to lower the emittance. While electrons pass through the bending magnet, synchrotron radiation will be generated covering a wide spectrum. There are other insertion devices in the storage ring which will generate shorter wavelength radiation as well. Synchrotron radiation has been widely used as diagnostic tool to measure the transverse and longitudinal profile. Three synchrotron light beam lines dedicated for diagnostics are under design and construction for the NSLS-II storage ring: two x-ray beam lines (pinhole and CRL) with the source points from Cell 22 BM{_}A (first bending in the DBA cell) and Cell22 three-pole wiggler; the third beam line is using visible part of radiation from Cell 30 BM{_}B (second bending magnet from the cell). Our paper focuses on the design of the visible beam line - SLM.

  10. VERTICAL RELAXATION OF A MOONLET PROPELLER IN SATURN'S A RING

    SciTech Connect (OSTI)

    Hoffmann, H.; Seiss, M.; Spahn, F. [Institute of Physics and Astronomy, University of Potsdam, D-14476 Golm (Germany)

    2013-03-01

    Two images, taken by the Cassini spacecraft near Saturn's equinox in 2009 August, show the Earhart propeller casting a 350 km long shadow, offering the opportunity to watch how the ring height, excited by the propeller moonlet, relaxes to an equilibrium state. From the shape of the shadow cast and a model of the azimuthal propeller height relaxation, we determine the exponential cooling constant of this process to be {lambda} = 0.07 {+-} 0.02 km{sup -1}, and thereby determine the collision frequency of the ring particles in the vertically excited region of the propeller to be {omega}{sub c}/{Omega} = 0.9 {+-} 0.2.

  11. IMPEDANCE BUDGET FOR CRAB CAVITY IN MEIC ELECTRON RING

    SciTech Connect (OSTI)

    S. Ahmed, B. Yunn, G. Krafft

    2012-07-01

    The Medium Energy Electron-Ion Collider (MEIC) at Jefferson Lab has been envisioned as a first stage high energy particle accelerator beyond the 12 GeV upgrade of CEBAF. The estimate of impedance budget is important from the view point of beam stability and matching with other accelerator components driving currents. The detailed study of impedance budget for electron ring has been performed by considering the current design parameters of the e-ring. A comprehensive picture of the calculations involved in this study has been illustrated in the paper.

  12. Nuclear reactor containment structure with continuous ring tunnel at grade

    DOE Patents [OSTI]

    Seidensticker, Ralph W.; Knawa, Robert L.; Cerutti, Bernard C.; Snyder, Charles R.; Husen, William C.; Coyer, Robert G.

    1977-01-01

    A nuclear reactor containment structure which includes a reinforced concrete shell, a hemispherical top dome, a steel liner, and a reinforced-concrete base slab supporting the concrete shell is constructed with a substantial proportion thereof below grade in an excavation made in solid rock with the concrete poured in contact with the rock and also includes a continuous, hollow, reinforced-concrete ring tunnel surrounding the concrete shell with its top at grade level, with one wall integral with the reinforced concrete shell, and with at least the base of the ring tunnel poured in contact with the rock.

  13. SPALLATION NEUTRON SOURCE RING-DESIGN AND CONSTRUCTION SUMMARY.

    SciTech Connect (OSTI)

    WEI,J.

    2005-05-16

    After six years, the delivery of components for the Spallation Neutron Source (SNS) accumulator ring (AR) and the transport lines was completed in Spring 2005. Designed to deliver 1.5 MW beam power (1.5 x 10{sup 14} protons of 1 GeV kinetic energy at a repetition rate of 60 Hz), stringent measures were implemented in the fabrication, test, and assembly to ensure the quality of the accelerator systems. This paper summarizes the design, R&D, and construction of the ring and transport systems.

  14. Ring-shaped polariton lasing in pillar microcavities

    SciTech Connect (OSTI)

    Kalevich, V. K. Afanasiev, M. M.; Lukoshkin, V. A.; Kavokin, K. V.; Tsintzos, S. I.; Savvidis, P. G.; Kavokin, A. V.

    2014-03-07

    Optically generated exciton-polaritons in cylindric semiconductor pillar microcavity with embedded GaAs/AlGaAs quantum wells demonstrate a clear polariton lasing regime. When exciting in the center of the pillar, we detect a ring-shaped emission, where the peak of intensity can be separated from the excitation spot by more than 10 μm. The spatial coherence of the ring emission is verified by interferometry measurements. These observations are interpreted by drift of the exciton polariton condensate away from the excitation spot due to its repulsion from the exciton reservoir and by its spatial confinement by the pillar boundary.

  15. Electron Spin Rotation And Matching Scheme For ELIC, A High-Luminosity Ring-Ring Electron-Ion Collider

    SciTech Connect (OSTI)

    Bogacz, A.; Chevtsov, P.; Derbenev, Y.; Krafft, G.; Zhang, Y.

    2009-08-04

    A unique design feature of a polarized Electron-Ion Collider (ELIC) based on CEBAF is its Figure-8 shaped storage rings for both electrons and ions, which significantly simplifies beam polarization maintenance and manipulation. The CEBAF accelerator is used as a full energy injector of polarized electron beams into the electron storage ring. While electron polarization is maintained vertical in arcs of the ring, a stable longitudinal spin at four collision points is achieved through vertical crossing bending magnets, solenoid spin rotators, and horizontal orbit bends. Spin matching technique needs to be implemented in order to enhance quantum self-polarization and minimize depolarization effects. In this paper, we also discuss several important issues related to the use of positron beams, radiative polarization and quantum depolarization effects, as well as spin in ELIC.

  16. Loss-free method of charging accumulator rings

    DOE Patents [OSTI]

    Maschke, Alfred W.

    1979-01-01

    A method for the production of high current pulses of heavy ions having an atomic weight greater than 100. Also a linear accelerator based apparatus for carrying out said method. Pulses formed by the method of the subject invention are suitable for storage in a storage ring. The accumulated pulses may be used in inertial fusion apparatus.

  17. Suppression of decoherence in a graphene monolayer ring

    SciTech Connect (OSTI)

    Smirnov, D. Rode, J. C.; Haug, R. J.

    2014-08-25

    The influence of high magnetic fields on coherent transport is investigated. A monolayer graphene quantum ring is fabricated and the Aharonov-Bohm effect is observed. For increased magnitude of the magnetic field, higher harmonics appear. This phenomenon is attributed to an increase of the phase coherence length due to reduction of spin flip scattering.

  18. Muon g-2 ring moving up Illinois river

    SciTech Connect (OSTI)

    2013-07-20

    This clip shows the "Miss Katie" pushing the muon g-2 ring upstream on the Illinois River, and passing through the Peoria Lock and Dam as it travels toward Lemont, where it will be unloaded onto the special Emmert transporter and driven to Fermilab.

  19. Filter holder assembly having extended collar spacer ring

    DOE Patents [OSTI]

    Alvin, Mary Anne (Pittsburgh, PA); Bruck, Gerald J. (Murrysville, PA)

    2002-01-01

    A filter holder assembly is provided that utilizes a fail-safe regenerator unit with an annular spacer ring having an extended metal collar for containment and positioning of a compliant ceramic gasket used in the assembly. The filter holder assembly is disclosed for use with advanced composite, filament wound, and metal candle filters.

  20. Fermilab Recycler Ring: Technical design report. Revision 1.1

    SciTech Connect (OSTI)

    Jackson, G.

    1996-07-01

    This report describes the technical design of the Fermilab Recycler Ring. The purpose of the Recycler is to augment the luminosity increase anticipated from the implementation of the Fermi III upgrade project, which has as its main component the Fermilab Main Injector construction project. The Recycler is a fixed 8 GeV kinetic energy storage ring. It is located in the Main Injector tunnel directly above the Main Injector beamline, near the ceiling. The construction schedule calls for the installation of the Recycler ring before the installation shutdown of the Main Injector. This aggressive construction schedule is made possible by the exclusive use of permanent magnets in the ring lattice, removing the need for expensive conventional iron/copper magnet construction along with the related power supplies, cooling water system, and electrical safety systems. The location, operating energy, and mode of construction are chosen to minimize operational impacts on both Fermilab`s ongoing High Energy Physics program and the Main Injector construction project.

  1. O-Ring sealing arrangements for ultra-high vacuum systems

    DOE Patents [OSTI]

    Kim, Chang-Kyo; Flaherty, Robert

    1981-01-01

    An all metal reusable O-ring sealing arrangement for sealing two concentric tubes in an ultra-high vacuum system. An O-ring of a heat recoverable alloy such as Nitinol is concentrically positioned between protruding sealing rings of the concentric tubes. The O-ring is installed between the tubes while in a stressed martensitic state and is made to undergo a thermally induced transformation to an austenitic state. During the transformation the O-ring expands outwardly and contracts inwardly toward a previously sized austenitic configuration, thereby sealing against the protruding sealing rings of the concentric tubes.

  2. Status of the MEIC ion collider ring design (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Status of the MEIC ion collider ring design Citation Details In-Document Search Title: Status of the MEIC ion collider ring design We present an update on the design of the ion ...

  3. Interaction-Region Design Options for a Linac-Ring LHeC (Conference...

    Office of Scientific and Technical Information (OSTI)

    Interaction-Region Design Options for a Linac-Ring LHeC Citation Details In-Document Search Title: Interaction-Region Design Options for a Linac-Ring LHeC The interaction-region ...

  4. A Feasibility Study of an e e- Ring Collider for Higgs Factory...

    Office of Scientific and Technical Information (OSTI)

    A Feasibility Study of an e e- Ring Collider for Higgs Factory Citation Details In-Document Search Title: A Feasibility Study of an e e- Ring Collider for Higgs Factory Authors: ...

  5. Ion Effects in the PEP-II High Energy Ring (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    Ion Effects in the PEP-II High Energy Ring Citation Details In-Document Search Title: Ion Effects in the PEP-II High Energy Ring We summarize the expected ion effects in the PEP-II ...

  6. Ring Current Pressure Estimation with RAM-SCB using Data Assimilation...

    Office of Scientific and Technical Information (OSTI)

    Ring Current Pressure Estimation with RAM-SCB using Data Assimilation and VanAllen Probe Flux Data Citation Details In-Document Search Title: Ring Current Pressure Estimation with ...

  7. Ring Current Pressure Estimation with RAM-SCB using Data Assimilation...

    Office of Scientific and Technical Information (OSTI)

    Conference: Ring Current Pressure Estimation with RAM-SCB using Data Assimilation and VanAllen Probe Flux Data Citation Details In-Document Search Title: Ring Current Pressure ...

  8. PHOTOMETRIC ANALYSIS OF HS Aqr, EG Cep, VW LMi, AND DU Boo

    SciTech Connect (OSTI)

    Djurasevic, G.; Latkovic, O.; Bastuerk, Oe.; Y Latin-Small-Letter-Dotless-I lmaz, M.; Cal Latin-Small-Letter-Dotless-I skan, S.; Senavc Latin-Small-Letter-Dotless-I , H. V.; K Latin-Small-Letter-Dotless-I l Latin-Small-Letter-Dotless-I coglu, T.; Ekmekci, F.; Tanr Latin-Small-Letter-Dotless-I verdi, T.

    2013-03-15

    We analyze new multicolor light curves for four close late-type binaries: HS Aqr, EG Cep, VW LMi, and DU Boo, in order to determine the orbital and physical parameters of the systems and estimate the distances. The analysis is done using the modeling code of G. Djurasevic, and is based on up-to-date measurements of spectroscopic elements. All four systems have complex, asymmetric light curves that we model by including bright or dark spots on one or both components. Our findings indicate that HS Aqr and EG Cep are in semi-detached, while VW LMi and DU Boo are in overcontact configurations.

  9. DOE - Office of Legacy Management -- E I Du Pont - NJ 06

    Office of Legacy Management (LM)

    - NJ 06 FUSRAP Considered Sites E.I. Dupont, NJ Alternate Name(s): E.I. Du Pont De Nemours and Company E.I. Du Pont Company Dupont Chambers Works Plant NJ.06-1 NJ.06-5 Location: Pennsville and Carney Townships, Southeast bank of the Delaware River, Deepwater, New Jersey NJ.06-5 Historical Operations: Development of a process for converting uranium oxide to uranium tetraflouride, production of uranium tetraflouride, research into conversion of uranium oxide to uranium metal, and production of

  10. Status of the PEP-II B-Factory High Energy Ring (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    Subject: 43 PARTICLE ACCELERATORS; CONSTRUCTION; DESIGN; DIPOLES; ELECTRONS; PRODUCTION; QUADRUPOLES; STANFORD LINEAR ACCELERATOR CENTER; STORAGE RINGS; VACUUM SYSTEMS Word Cloud ...

  11. Status of the MEIC ion collider ring design

    SciTech Connect (OSTI)

    None, None

    2015-07-14

    We present an update on the design of the ion collider ring of the Medium-energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab. The design is based on the use of super-ferric magnets. It provides the necessary momentum range of 8 to 100 GeV/c for protons and ions, matches the electron collider ring design using PEP-II components, fits readily on the JLab site, offers a straightforward path for a future full-energy upgrade by replacing the magnets with higher-field ones in the same tunnel, and is more cost effective than using presently available current-dominated super-conducting magnets. We describe complete ion collider optics including an independently-designed modular detector region.

  12. On the Grothendieck rings of equivariant fusion categories

    SciTech Connect (OSTI)

    Burciu, Sebastian

    2015-07-15

    In this paper, we describe a Mackey type decomposition for group actions on abelian categories. This allows us to define new Mackey functors which associates to any subgroup the K-theory of the corresponding equivariantized abelian category. In the case of an action by tensor autoequivalences, the Mackey functor at the level of Grothendieck rings has a Green functor structure. As an application we give a description of the Grothendieck rings of equivariantized fusion categories under group actions by tensor autoequivalences on graded fusion categories. In this settings, a new formula for the tensor product of any two simple objects of an equivariantized fusion category is given, simplifying the fusion formula from Burciu and Natale [J. Math. Phys. 54, 013511 (2013)].

  13. High-Power Ka-Band Window and Resonant Ring

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2006-11-29

    A stand-alone 200 MW rf test station is needed for carrying out development of accelerator structures and components for a future high-gradient multi-TeV collider, such as CLIC. A high-power rf window is needed to isolate the test station from a structure element under test. This project aimed to develop such a window for use at a frequency in the range 30-35 GHz, and to also develop a high-power resonant ring for testing the window. During Phase I, successful conceptual designs were completed for the window and the resonant ring, and cold tests of each were carried out that confirmed the designs.

  14. FREQUENCY AND DIFFUSION MAPS FOR THE SNS RING.

    SciTech Connect (OSTI)

    PAPAPHILIPPOU,Y.

    2001-06-18

    Using a single particle dynamics approach: the major magnetic non-linearities of the SNS accumulator ring are studied. Frequency maps are employed in order to display the global dynamics of the beam, for several working points. By means of diffusion maps the major resonances are explored and their bandwidth is estimated. The global tune diffusion coefficient is finally used to compare and choose the best working point.

  15. Block copolymer adhesion promoters via ring-opening metathesis polymerization

    DOE Patents [OSTI]

    Kent, Michael S.; Saunders, Randall

    1997-01-01

    Coupling agents based on functionalized block copolymers for bonding thermoset polymers to solid materials. These are polymers which possess at least two types of functional groups, one which is able to attach to and react with solid surfaces, and another which can react with a thermoset resin, which are incorporated as pendant groups in monomers distributed in blocks (typically two) along the backbone of the chain. The block copolymers in this invention are synthesized by living ring-opening metathesis polymerization.

  16. Ion polarization in the MEIC figure-8 ion collider ring

    SciTech Connect (OSTI)

    V.S. Morozov, Ya.S. Derbenev, Y. Zhang, P. Chevtsov, A.M. Kondratenko, M.A. Kondratenko, Yu.N. Filatov

    2012-07-01

    The nuclear physics program envisaged at the Medium-energy Electron-Ion Collider (MEIC) currently being developed at the Jefferson Lab calls for collisions of 3-11 GeV/c longitudinally polarized electrons and 20-100 GeV/c, in equivalent proton momentum, longitudinally/ transversely polarized protons/ deuterons/ light ions. We present a scheme that provides the required ion polarization arrangement in the MEIC's ion collider ring.

  17. From Protein Structure to Function: Ring Cycle for Dilating and

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

    Constricting the Nuclear Pore From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore Print Nuclear pore complexes (NPCs) act as the central gatekeepers for selective transport between the cytoplasm and the nucleus. They allow the exchange of selected proteins and ribonucleoproteins, while preventing the transport of material not meant to cross the nuclear envelope. The NPC transport channel is the largest and most complex transport conduit in the

  18. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

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

    Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but

  19. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

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

    Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but

  20. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

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

    Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but

  1. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

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

    Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but

  2. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

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

    Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but

  3. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

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

    Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but

  4. Thermoset polymers via ring opening metathesis polymerization of functionalized oils

    DOE Patents [OSTI]

    Larock, Richard C; Henna, Phillip H; Kessier, Michael R

    2012-11-27

    The invention provides a method for producing a thermosetting resin from renewable oils, the method comprising supplying renewable oil molecules containing strained ring alkene moieties; reacting the alkene moieties with cyclic alkenes to create a polymer; and repeating the above two steps until the resin having desired characteristics are obtained. Also provided is a thermoset resin comprising functionalized renewable oil polymerized with a co-monomer.

  5. Bichromatic emission and multimode dynamics in bidirectional ring lasers

    SciTech Connect (OSTI)

    Perez-Serrano, Antonio; Javaloyes, Julien; Balle, Salvador

    2010-04-15

    The multimode dynamics of a two-level ring laser is explored numerically using a bidirectional traveling wave model retaining the spatial effects due to the presence of counter-propagating electric fields in the population inversion. Dynamical regimes where the emission in each direction occurs at different wavelengths are studied. Mode-locked unidirectional emission for large gain bandwidth and relatively small detuning is reported.

  6. DuPont extends CFC production after EPA warns of scarcity

    SciTech Connect (OSTI)

    Kirschner, E.

    1994-01-05

    DuPont reversed its voluntary commitment to phase out CFC production at the end of 1994 to prevent a possible shortage for automotive air conditioning repairs. In a December letter, the US EPA asked Dupont to continue producing its full 1995 allowance of 76 million tons of CFC-12 under the Montreal Protocol.

  7. PLJ3ASE RUSH ANALYTICAL DATA SHEET

    Office of Legacy Management (LM)

    for F U Beta Stamping wrahor8.fm jqtip6 of U heated in 900 P salt No Ro 5 bath. ' :,.a r ' .. ? ' ). ;..- *fhv 11 - n ... .I < Oil 3 PH kmph No. . . , r, . ...

  8. From Neighborhoods to Nationwide, ASE Congressional briefing

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

    eere.energy.gov 1 From Neighborhoods to Nationwide Danielle Sass Byrnett Supervisor, Better Buildings Residential Residential Energy Efficiency Upgrades eere.energy.gov 2 Better ...

  9. Microsoft Word - 2013 KCP ASES Final

    National Nuclear Security Administration (NNSA)

    2013 Annual Site Environmental Summary U.S. Department of Energy National Nuclear Security Administration Kansas City Plant September 2014 i U.S. Department of Energy National Nuclear Security Administration Annual Site Environmental Summary Report Kansas City Plant Table of Contents Page U.S. Department of Energy National Nuclear Security Administration ................ i Table of Contents ...................................................................................................... i

  10. Microsoft Word - 2013 KCP ASES Final

    National Nuclear Security Administration (NNSA)

    ... The overlying shale contains a poorly-defined coal horizon ... Three natural gas-fired hot water boilers provide heating ... at the Central Utility Plant (CUP), a fuel cell ...

  11. More Powerful, Longer-Lasting Batteries Rings Around the Earth

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

    Powerful, Longer-Lasting Batteries Rings Around the Earth A QUARTERLY RESEARCH & DEVELOPMENT JOURNAL VOLUME 5, NO. 1 BeThereNow Enhancing Long-distance Collaborations SPRING * 2003 S A N D I A T E C H N O L O G Y Sandia Technology is a quarterly journal published by Sandia National Laboratories. Sandia is a multiprogram engineering and science laboratory operated by Sandia Corporation, a Lockheed Martin company, for the Department of Energy. With main facilities in Albuquerque, New Mexico,

  12. Status of the ATF Damping Ring BPM Upgrade Project

    SciTech Connect (OSTI)

    Briegel, C.; Eddy, N.; Haynes, B.; May, J.; McCormick, D.; Nelson, J.; Nicklaus, D.; Prieto, P.; Rechenmacher, R.; Smith, T.; Teranuma, N.; Urakawa, J.; Voy, D.; Wendt, M.; Woodley, M.; /SLAC

    2011-12-01

    A substantial upgrade of the beam position monitors (BPM) at the ATF (Accelerator Test Facility) damping ring is currently in progress. Implementing digital read-out signal processing techniques in line with an optimized, low-noise analog downconverter, a resolution well below 1 mum could be demonstrated at 20 (of 96) upgraded BPM stations. The narrowband, high resolution BPM mode permits investigation of all types of non-linearities, imperfections and other obstacles in the machine which may limit the very low target aimed vertical beam emittance of < 2 pm. The technical status of the project, first beam measurements and an outlook to it's finalization are presented.

  13. Block copolymer adhesion promoters via ring-opening metathesis polymerization

    DOE Patents [OSTI]

    Kent, M.S.; Saunders, R.

    1997-02-18

    Coupling agents are disclosed based on functionalized block copolymers for bonding thermoset polymers to solid materials. These are polymers which possess at least two types of functional groups, one which is able to attach to and react with solid surfaces, and another which can react with a thermoset resin, which are incorporated as pendant groups in monomers distributed in blocks (typically two) along the backbone of the chain. The block copolymers in this invention are synthesized by living ring-opening metathesis polymerization. 18 figs.

  14. Reliability analysis for LEB ring magnet power system in SSC

    SciTech Connect (OSTI)

    Smedley, K.

    1991-11-01

    The LEB ring magnet power system contains six subsystems, supervisory control, power supplies, regulation, DC bus, resonant cells, and fault sensing network. The system availability of the total LEB RMPS is required to be 0.999. The work in this paper is to allocate the overall LEB RMPS reliability requirement into reliability requirements for each of the subsystems and lower-tier items. The Feasibility-of-Objective technique combining with engineering experience is the key for the allocation. MIL-HDBK-217F is used to derate SCR components. 7 refs., 5 figs.

  15. BEAM-BEAM SIMULATIONS FOR THE ERHIC ELECTRON RING.

    SciTech Connect (OSTI)

    MONTAG, C.

    2005-05-16

    To study collisions between polarized electrons and heavy ions or polarized protons at high energy, adding a 10 GeV electron storage ring to the existing RHIC facility is currently under consideration. To achieve high luminosities of several 10{sup 33} cm{sup -2} sec{sup -1} range, a vertical beam-beam tuneshift parameter of {zeta}{sub y} = 0.08 is required for the electron beam. Simulation studies are being performed to study the feasibility of this high tuneshift parameter and explore the potential for even higher tuneshifts. Recent results of these studies are presented.

  16. Interface ring for gas turbine fuel nozzle assemblies

    DOE Patents [OSTI]

    Fox, Timothy A.; Schilp, Reinhard

    2016-03-22

    A gas turbine combustor assembly including a combustor liner and a plurality of fuel nozzle assemblies arranged in an annular array extending within the combustor liner. The fuel nozzle assemblies each include fuel nozzle body integral with a swirler assembly, and the swirler assemblies each include a bellmouth structure to turn air radially inwardly for passage into the swirler assemblies. A radially outer removed portion of each of the bellmouth structures defines a periphery diameter spaced from an inner surface of the combustor liner, and an interface ring is provided extending between the combustor liner and the removed portions of the bellmouth structures at the periphery diameter.

  17. INJECTION CARBON STRIPPING FOIL ISSUES IN THE SNS ACCUMULATOR RING.

    SciTech Connect (OSTI)

    BEEBE-WANG,J.; LEE,Y.Y.; RAPARIA,D.; WEI,J.

    2001-06-18

    We are reporting the results of studies on issues related to the injection stripping foil in the Spallation Neutron Source (SNS) accumulator ring. The problems related to foil heating and foil lifetime, such as current density distribution and temperature distribution in the foil, are investigated. The impact of injection errors on the beam losses at the foil is studied. The particle traversal rate and the beam losses due to scattering in the foil are summarized. Finally, SNS end-to-end simulation results of the foil-missing rate, the foil-hitting rate and the maximum foil temperature are presented.

  18. Ring laser having an output at a single frequency

    DOE Patents [OSTI]

    Hackell, Lloyd A.

    1991-01-01

    A ring laser is disclosed that produces a single frequency of laser radiation in either the pulsed mode of operation or the continuous waveform (cw) mode of operation. The laser comprises a ring laser in a bowtie configuration, a birefringent gain material such as Nd:YLF, an improved optical diode that supports laser oscillation having a desired direction of travel and linear polarization, and a Q-switch. An output coupler (mirror) having a high reflectivity, such as 94%, is disclosed. Also disclosed is a self-seeded method of operation in which the laser can provide a pulse or a series of pulses of high power laser radiation at a consistent single frequency with a high degree of amplitude stability and temporal stability. In operation, the laser is operated in continuous waveform (cw) at a low power output with the Q-switch introducing a loss into the resonating cavity. Pumping is continued at a high level, causing the gain material to store energy. When a pulse is desired, the Q-switch is actuated to substantially reduce the losses so that a pulse can build up based on the low level cw oscillation. The pulse quickly builds, using the stored energy in the gain medium to provide a high power output pulse. The process may be repeated to provide a series of high power pulses of a consistent single frequency.

  19. Operational advances in ring current modeling using RAM-SCB

    SciTech Connect (OSTI)

    Welling, Daniel T; Jordanova, Vania K; Zaharia, Sorin G; Morley, Steven K

    2010-12-03

    The Ring current Atmosphere interaction Model with Self-Consistently calculated 3D Magnetic field (RAM-SCB) combines a kinetic model of the ring current with a force-balanced model of the magnetospheric magnetic field to create an inner magnetospheric model that is magnetically self consistent. RAM-SCB produces a wealth of outputs that are valuable to space weather applications. For example, the anisotropic particle distribution of the KeV-energy population calculated by the code is key for predicting surface charging on spacecraft. Furthermore, radiation belt codes stand to benefit substantially from RAM-SCB calculated magnetic field values and plasma wave growth rates - both important for determining the evolution of relativistic electron populations. RAM-SCB is undergoing development to bring these benefits to the space weather community. Data-model validation efforts are underway to assess the performance of the system. 'Virtual Satellite' capability has been added to yield satellite-specific particle distribution and magnetic field output. The code's outer boundary is being expanded to 10 Earth Radii to encompass previously neglected geosynchronous orbits and allow the code to be driven completely by either empirical or first-principles based inputs. These advances are culminating towards a new, real-time version of the code, rtRAM-SCB, that can monitor the inner magnetosphere conditions on both a global and spacecraft-specific level. This paper summarizes these new features as well as the benefits they provide the space weather community.

  20. Sol-gel chemistry by ring-opening polymerization

    SciTech Connect (OSTI)

    RAHIMIAN,KAMYAR; LOY,DOUGLAS A.

    2000-02-07

    Sol-gel processing of materials is plagued by shrinkage during polymerization of the alkoxide monomers and processing (aging and drying) of the resulting gels. The authors have developed a new class of hybrid organic-inorganic materials based on the solventless ring-opening polymerization (ROP) of monomers bearing the 2,2,5,5-tetramethyl-2,5-disilaoxacyclopentyl group, which permits them to drastically reduce shrinkage in sol-gel processed materials. Because the monomers are polymerized through a chain growth mechanism catalyzed by base rather than the step growth mechanism normally used in sol-gel systems, hydrolysis and condensation products are entirely eliminated. Furthermore, since water is not required for hydrolysis, an alcohol solvent is not necessary. Monomers with two disilaoxacyclopentyl groups, separated by a rigid phenylene group or a more flexible alkylene group, were prepared through disilylation of the corresponding diacetylenes, followed by ring closure and hydrogenation. Anionic polymerization of these materials, either neat or with 2,2,5,5-tetramethyl-2,5-disila-1-oxacyclopentane as a copolymer, affords thermally stable transparent gels with no visible shrinkage. These materials provide an easy route to the introduction of sol-gel type materials in encapsulation of microelectronics, which they have successfully demonstrated.

  1. ORBIT : BEAM DYNAMICS CALCULATIONS FOR HIGH - INTENSITY RINGS.

    SciTech Connect (OSTI)

    HOLMES,J.A.; DANILOV,V.; GALAMBOS,J.; SHISHLO,A.; COUSINEAU,S.; CHOU,W.; MICHELOTTI,L.; OSTIGUY,F.; WEI,J.

    2002-06-03

    We are developing a computer code, ORBIT, specifically for beam dynamics calculations in high-intensity rings. Our approach allows detailed simulation of realistic accelerator problems. ORBIT is a particle-in-cell tracking code that transports bunches of interacting particles through a series of nodes representing elements, effects, or diagnostics that occur in the accelerator lattice. At present, ORBIT contains detailed models for strip-foil injection including painting and foil scattering; rf focusing and acceleration; transport through various magnetic elements; longitudinal and transverse impedances; longitudinal, transverse, and three-dimensional space charge forces; collimation and limiting apertures; and the calculation of many useful diagnostic quantities. ORBIT is an object-oriented code, written in C++ and utilizing a scripting interface for the convenience of the user. Ongoing improvements include the addition of a library of accelerator maps, BEAMLINE/MXYZPTLK the introduction of a treatment magnet errors and fringe fields; the conversion of the scripting interface to the standard scripting language, Python; and the parallelization of the computations using MPI. The ORBIT code is an open source, powerful, and convenient tool for studying beam dynamics in high-intensity rings.

  2. LIFETIME PREDICTION FOR MODEL 9975 O-RINGS IN KAMS

    SciTech Connect (OSTI)

    Hoffman, E.; Skidmore, E.

    2009-11-24

    The Savannah River Site (SRS) is currently storing plutonium materials in the K-Area Materials Storage (KAMS) facility. The materials are packaged per the DOE 3013 Standard and transported and stored in KAMS in Model 9975 shipping packages, which include double containment vessels sealed with dual O-rings made of Parker Seals compound V0835-75 (based on Viton{reg_sign} GLT). The outer O-ring of each containment vessel is credited for leaktight containment per ANSI N14.5. O-ring service life depends on many factors, including the failure criterion, environmental conditions, overall design, fabrication quality and assembly practices. A preliminary life prediction model has been developed for the V0835-75 O-rings in KAMS. The conservative model is based primarily on long-term compression stress relaxation (CSR) experiments and Arrhenius accelerated-aging methodology. For model development purposes, seal lifetime is defined as a 90% loss of measurable sealing force. Thus far, CSR experiments have only reached this target level of degradation at temperatures {ge} 300 F. At lower temperatures, relaxation values are more tolerable. Using time-temperature superposition principles, the conservative model predicts a service life of approximately 20-25 years at a constant seal temperature of 175 F. This represents a maximum payload package at a constant ambient temperature of 104 F, the highest recorded in KAMS to date. This is considered a highly conservative value as such ambient temperatures are only reached on occasion and for short durations. The presence of fiberboard in the package minimizes the impact of such temperature swings, with many hours to several days required for seal temperatures to respond proportionately. At 85 F ambient, a more realistic but still conservative value, bounding seal temperatures are reduced to {approx}158 F, with an estimated seal lifetime of {approx}35-45 years. The actual service life for O-rings in a maximum wattage package likely lies

  3. Planning and Prototyping for a Storage Ring Measurement of the Proton Electric Dipole Moment

    SciTech Connect (OSTI)

    Talman, Richard

    2015-07-01

    Electron and proton EDM's can be measured in "frozen spin" (with the beam polarization always parallel to the orbit, for example) storage rings. For electrons the "magic" kinetic energy at which the beam can be frozen is 14.5 MeV. For protons the magic kinetic energy is 230 MeV. The currently measured upper limit for the electron EDM is much smaller than the proton EDM upper limit, which is very poorly known. Nevertheless, because the storage ring will be an order of magnitude cheaper, a sensible plan is to first build an all-electric electron storage ring as a prototype. Such an electron ring was successfully built at Brookhaven, in 1954, as a prototype for their AGS ring. This leaves little uncertainty concerning the cost and performance of such a ring. (This is documentedin one of the Physical Review papers mentioned above.)

  4. Active Interrogation Observables for Enrichment Determination of DU Shielded HEU Metal Assemblies with Limited Geometrical Information

    SciTech Connect (OSTI)

    Pena, Kirsten E; McConchie, Seth M; Crye, Jason Michael; Mihalczo, John T

    2011-01-01

    Determining the enrichment of highly enriched uranium (HEU) metal assemblies shielded by depleted uranium (DU) proves a unique challenge to currently employed measurement techniques. Efforts to match time-correlated neutron distributions obtained through active interrogation to Monte Carlo simulations of the assemblies have shown promising results, given that the exact geometries of both the HEU metal assemblies and DU shields are known from imaging and fission site mapping. In certain situations, however, it is desirable to obtain enrichment with limited or no geometrical information of the assemblies being measured. This paper explores the possibility that the utilization of observables in the interrogation of assemblies by time-tagged D-T neutrons, including time-correlated distribution of neutrons and gammas using liquid scintillators operating on the fission chain time scale, can lead to enrichment determination without a complete set of geometrical information.

  5. NREL Science Central to Success of New Biofuels Projects: DuPont-NREL

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

    Partnership Delivered Key Innovations for Large Scale Cellulosic Ethanol Facility in Iowa - News Feature | NREL NREL Science Central to Success of New Biofuels Projects: DuPont-NREL Partnership Delivered Key Innovations for Large Scale Cellulosic Ethanol Facility in Iowa February 23, 2015 This photo shows two men in front of a bin the size of a golf cart. Both men are reaching into the bin to touch the biomass inside. NREL Biochemical Conversion Manager Rick Elander toured NREL's Biorefinery

  6. DuPont’s Cellulosic Ethanol Grand Opening Marks a Milestone for the Advanced Biofuels Industry

    Office of Energy Efficiency and Renewable Energy (EERE)

    On a bright, crisp October morning in Iowa, I had the privilege to speak at the grand opening of DuPont’s cellulosic ethanol biorefinery—the fourth biorefinery of its kind in the United States and the largest in the world. This impressive plant is equipped to produce 30 million gallons of ethanol each year from the leftover stalks and leaves of the corn plant, called corn stover.

  7. Fond du Lac Band Leads Climate Resilience Efforts on Lake Superior Chippewa Indian Reservation

    Office of Energy Efficiency and Renewable Energy (EERE)

    From the White House Council on Environmental Quality blog: Last Friday I had the pleasure of visiting the Fond du Lac Band of Lake Superior Chippewa Indian Reservation. We toured the reservation and facilities with tribal Chairwoman Karen Diver, a member of the President’s State, Local, and Tribal Leaders Task Force on Climate Preparedness and Resilience, and the Tribe’s Resource Management Division.

  8. Status of the PEP-II B-Factory High Energy Ring (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    is an electron storage ring under construction at SLAC. Significant progress has been ... Language: English Subject: 43 PARTICLE ACCELERATORS; CONSTRUCTION; DESIGN; DIPOLES; ...

  9. FODO-Supercell Based Compact Ring Design with Tunable Momentum Compaction and Optimized Dynamic Aperture

    SciTech Connect (OSTI)

    Sun, Yipeng; /SLAC

    2012-05-11

    A storage ring with tunable momentum compaction has the advantage in achieving different RMS bunch length with similar RF capacity, which is potentially useful for many applications, such as linear collider damping ring and pre-damping ring where injected beam has a large energy spread and a large transverse emittance. A tunable bunch length also makes the commissioning and fine tuning easier in manipulating the single bunch instabilities. In this paper, a compact ring design based on a supercell is presented, which achieves a tunable momentum compaction while maintaining a large dynamic aperture.

  10. Wafer-level packaging with compression-controlled seal ring bonding

    DOE Patents [OSTI]

    Farino, Anthony J

    2013-11-05

    A device may be provided in a sealed package by aligning a seal ring provided on a first surface of a first semiconductor wafer in opposing relationship with a seal ring that is provided on a second surface of a second semiconductor wafer and surrounds a portion of the second wafer that contains the device. Forcible movement of the first and second wafer surfaces toward one another compresses the first and second seal rings against one another. A physical barrier against the movement, other than the first and second seal rings, is provided between the first and second wafer surfaces.

  11. Possible bias in tree-ring time series due to mortality (Journal...

    Office of Scientific and Technical Information (OSTI)

    Subject: 54 ENVIRONMENTAL SCIENCES; 63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.; TREE RINGS; TIME-SERIES ANALYSIS; AIR POLLUTION; ...

  12. AGING PERFORMANCE OF MODEL 9975 PACKAGE FLUOROELASTOMER O-RINGS

    SciTech Connect (OSTI)

    Hoffman, E.; Daugherty, W.; Skidmore, E.; Dunn, K.; Fisher, D.

    2011-05-31

    The influence of temperature and radiation on Viton{reg_sign} GLT and GLT-S fluoroelastomer O-rings is an ongoing research focus at the Savannah River National Laboratory. The O-rings are credited for leaktight containment in the Model 9975 shipping package used for transportation of plutonium-bearing materials. At the Savannah River Site, the Model 9975 packages are being used for interim storage. Primary research efforts have focused on surveillance of O-rings from actual packages, leak testing of seals at bounding aging conditions and the effect of aging temperature on compression stress relaxation behavior, with the goal of service life prediction for long-term storage conditions. Recently, an additional effort to evaluate the effect of aging temperature on the oxidation of the materials has begun. Degradation in the mechanical properties of elastomers is directly related to the oxidation of the polymer. Sensitive measurements of the oxidation rate can be performed in a more timely manner than waiting for a measurable change in mechanical properties, especially at service temperatures. Measuring the oxidation rate therefore provides a means to validate the assumption that the degradation mechanisms(s) do not change from the elevated temperatures used for accelerated aging and the lower service temperatures. Monitoring the amount of oxygen uptake by the material over time at various temperatures can provide increased confidence in lifetime predictions. Preliminary oxygen consumption analysis of a Viton GLT-based fluoroelastomer compound (Parker V0835-75) using an Oxzilla II differential oxygen analyzer in the temperature range of 40-120 C was performed. Early data suggests oxygen consumption rates may level off within the first 100,000 hours (10-12 years) at 40 C and that sharp changes in the degradation mechanism (stress-relaxation) are not expected over the temperature range examined. This is consistent with the known long-term heat aging resistance of

  13. Prompt Neutron Time Decay in Single HEU and DU Metal Annular Storage Castings

    SciTech Connect (OSTI)

    Pena, Kirsten E [ORNL] [ORNL; McConchie, Seth M [ORNL] [ORNL; Mihalczo, John T [ORNL] [ORNL

    2010-01-01

    Previous measurements of highly enriched uranium (HEU) storage castings performed by Oak Ridge National Laboratory (ORNL) at the Y-12 National Security Complex showed a prompt neutron time decay that is not exponential. These measurements showed that multiple time constants originating from multiplication, time-of-flight, scattering in the assembly and room return could be associated with this prompt neutron decay. In this work, the contribution not associated with neutron multiplication was investigated via measurements with a depleted uranium (DU) casting. The measurements at ORNL used an annular (5.0-in OD, 3.5-in ID, 6.0-in H) DU casting with a time-tagged 252Cf source, centered vertically on the axis, and four closely coupled 1 1 6-in.-long plastic scintillators with -in.- thick lead shielding adjacent to the outer surface of the casting. This setup was identical to the configuration used in the previously performed measurements with HEU castings at Y-12. The time correlation between fission events and detections in the plastic scintillators was measured, as well as the time distribution of coincidences between multiple detectors within a 512-ns time window. The measurement results were then compared to MCNP-PoliMi calculations and the previous HEU measurements. Time constants from decay fits to the HEU and DU data were compared to characterize the contributions resulting from multiplication, time-of-flight, and scattering.

  14. Thermal depinning of fluxons in discrete Josephson rings

    SciTech Connect (OSTI)

    Mazo, J. J.; Naranjo, F.; Segall, K.

    2008-11-01

    We study the thermal depinning of single fluxons in rings made of Josephson junctions. Due to thermal fluctuations a fluxon can be excited from its energy minima and move through the array, causing a voltage across each junction. We find that for the initial depinning, the fluxon behaves as a single particle and follows a Kramers-type escape law. However, under some conditions this single-particle description breaks down. At low values of the discreteness parameter and low values of the damping, the depinning rate is larger than what the single-particle result would suggest. In addition, for some values of the parameters the fluxon can undergo low-voltage diffusion before switching to the high-voltage whirling mode. This type of diffusion is similar to phase diffusion in a single junction but occurs without frequency-dependent damping. We study the switching to the whirling state as well.

  15. Exact physical model for magnets in storage rings

    SciTech Connect (OSTI)

    Maletic, D.; Ruggiero, A.G.

    1992-12-31

    In this report we try to make estimates of both kinematic and field effects on the stability of a particle motion, by employing a truly Maxwellian representation of the magnetic field in exact equations of motion. For this purpose we adopt a simple FODO cell model, which repeats periodically to infinity. This model includes only quadrupoles and drifts, leaving out the bending magnets to avoid the problem of the trajectory curvature. We think this model is a physically consistent approximation of a storage ring. We derive several models with different levels of approximation and compare them by evaluating the importance of these effects. The relevance to long-term stability is being investigated in the meantime by comparing the different models with extensive computer simulations. The results will be shown in a subsequent report.

  16. Polarized Ion Beams in Figure-8 Rings of JLab's MEIC

    SciTech Connect (OSTI)

    Derbenev, Yaroslav; Lin, Fanglei; Morozov, Vasiliy; Zhang, Yuhong; Kondratenko, Anatoliy; Kondratenko, M.A.; Filatov, Yury

    2014-07-01

    The Medium-energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab is designed to provide high polarization of both colliding beams. One of the unique features of JLab's MEIC is figure-8 shape of its rings. It allows preservation and control of polarization of all ion species including small-anomalous-magnetic-moment deuterons during their acceleration and storage. The figure-8 design conceptually expands the capability of obtaining polarized high-energy beams in comparison to conventional designs because of its property of having no preferred periodic spin direction. This allows one to control effectively the beam polarization by means of magnetic insertions with small field integrals. We present a complete scheme for preserving the ion polarization during all stages of acceleration and its control in the collider's experimental straights.

  17. Graphene Layer Growth Chemistry: Five-Six-Ring Flip Reaction

    SciTech Connect (OSTI)

    Whitesides, Russell; Domin, Dominik; Lester Jr., William A.; Frenklach, Michael

    2007-03-24

    A theoretical study revealed a new reaction pathway, in which a fused five and six-membered ring complex on the zigzag edge of a graphene layer isomerizes to reverse its orientation, or 'flips,' after activation by a gaseous hydrogen atom. The process is initiated by hydrogen addition to or abstraction from the surface complex. The elementary steps of the migration pathway were analyzed using density-functional theory (DFT) calculations to examine the region of the potential energy surface associated with the pathway. The DFT calculations were performed on substrates modeled by the zigzag edges of tetracene and pentacene. Rate constants for the flip reaction were obtained by the solution of energy master equation utilizing the DFT energies, frequencies, and geometries. The results indicate that this reaction pathway is competitive with other pathways important to the edge evolution of aromatic species in high temperature environments.

  18. Heating performances of a IC in-blanket ring array

    SciTech Connect (OSTI)

    Bosia, G.; Ragona, R.

    2015-12-10

    An important limiting factor to the use of ICRF as candidate heating method in a commercial reactor is due to the evanescence of the fast wave in vacuum and in most of the SOL layer, imposing proximity of the launching structure to the plasma boundary and causing, at the highest power level, high RF standing and DC rectified voltages at the plasma periphery, with frequent voltage breakdowns and enhanced local wall loading. In a previous work [1] the concept for an Ion Cyclotron Heating & Current Drive array (and using a different wave guide technology, a Lower Hybrid array) based on the use of periodic ring structure, integrated in the reactor blanket first wall and operating at high input power and low power density, was introduced. Based on the above concept, the heating performance of such array operating on a commercial fusion reactor is estimated.

  19. Ordinary mode instability associated with thermal ring distribution

    SciTech Connect (OSTI)

    Hadi, F.; Qamar, A.; Yoon, P. H.

    2015-02-15

    The purely growing ordinary (O) mode instability driven by excessive parallel temperature anisotropy has recently received renewed attention owing to its potential applicability to the solar wind plasma. Previous studies of O mode instability have assumed either bi-Maxwellian or counter-streaming velocity distributions. For solar wind plasma trapped in magnetic mirror-like geometry such as magnetic clouds or in the vicinity of the Earth's collisionless bow shock environment, however, the velocity distribution function may possess a loss-cone feature. The O-mode instability in such a case may be excited for cyclotron harmonics as well as the purely growing branch. The present paper investigates the O-mode instability for plasmas characterized by the parallel Maxwellian distribution and perpendicular thermal ring velocity distribution in order to understand the general stability characteristics.

  20. FIFTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    SciTech Connect (OSTI)

    Daugherty, W.; Hoffman, E.

    2010-11-01

    A series of experiments to monitor the aging performance of Viton{sup reg.} GLT O-rings used in the Model 9975 package has been ongoing for six years at the Savannah River National Laboratory. Sixty-seven mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 F. They were leak-tested initially and have been tested at nominal six month intervals to determine if they meet the criterion of leaktightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 F. High temperature aging continues for 36 GLT O-ring fixtures at 200--350 F. Room temperature leak test failures have been experienced in 5 of the GLT O-ring fixtures aging at 300 and 350 F, and in all 3 of the GLT O-ring fixtures aging at higher temperatures. No failures have yet been observed in GLT O-ring fixtures aging at 200 F for 30--48 months, which is still bounding to O-ring temperatures during storage in KAMS. High temperature aging continues for 6 GLT-S O-ring fixtures at 200--300 F. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 F. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 or 300 F for 19 months. For O-ring fixtures that have failed the room temperature leak test and been disassembled, the O-rings displayed a compression set ranging from 51--95%. This is significantly greater than seen to date for packages inspected during KAMS field surveillance (23% average). For GLT O-rings, service life based on the room temperature leak rate criterion is comparable to that predicted by compression stress relaxation (CSR) data at higher temperatures (350--400 F). While there are no comparable failure data yet at aging temperatures below 300 F, extrapolations of the data for GLT O-rings suggests that CSR model predictions provide a conservative prediction of

  1. 9-D polarized proton transport in the MEIC figure 8 collider ring - first steps

    SciTech Connect (OSTI)

    Meot, F.; Morozov, V. S.

    2015-05-03

    Spin tracking studies in the MEIC figure-8 collider ion ring are presented, based on a very preliminary design of the lattice. They provide numerical illustrations of some of the aspects of the figure-8 concept, including spin-rotator based spin control, and lay out the path towards a complete spin tracking simulation of a figure-8 ring.

  2. 9-D polarized proton transport in the MEIC figure-8 collider ring: first steps

    SciTech Connect (OSTI)

    Meot, F.; Morozov, V. S.

    2014-10-24

    Spin tracking studies in the MEIC figure-8 collider ion ring are presented, based on a very preliminary design of the lattice. They provide numerical illustrations of some of the aspects of the figure-8 concept, including spin-rotator based spin control, and lay out the path towards a complete spin tracking simulation of a figure-8 ring.

  3. FIFTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    SciTech Connect (OSTI)

    Daugherty, W.; Hoffman, E.

    2011-04-11

    A series of experiments to monitor the aging performance of Viton{reg_sign} GLT O-rings used in the Model 9975 package has been ongoing for six years at the Savannah River National Laboratory. Sixty-seven mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 F. They were leak-tested initially and have been tested at nominal six month intervals to determine if they meet the criterion of leaktightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 F. High temperature aging continues for 36 GLT O-ring fixtures at 200-350 F. Room temperature leak test failures have been experienced in 6 of the GLT O-ring fixtures aging at 300 and 350 F, and in all 3 of the GLT O-ring fixtures aging at higher temperatures. No failures have yet been observed in GLT O-ring fixtures aging at 200 F for 30-48 months, which is still bounding to O-ring temperatures during storage in KAMS. High temperature aging continues for 6 GLT-S O-ring fixtures at 200-300 F. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 F. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 or 300 F for 19 months. For O-ring fixtures that have failed the room temperature leak test and been disassembled, the Orings displayed a compression set ranging from 51-95%. This is significantly greater than seen to date for packages inspected during KAMS field surveillance (23% average). For GLT O-rings, service life based on the room temperature leak rate criterion is comparable to that predicted by compression stress relaxation (CSR) data at higher temperatures (350-400 F). While there are no comparable failure data yet at aging temperatures below 300 F, extrapolations of the data for GLT O-rings suggests the CSR model predictions provide a conservative prediction of service

  4. Evaluation of the two-photon absorption characteristics of GaSb/GaAs quantum rings

    SciTech Connect (OSTI)

    Wagener, M. C.; Botha, J. R.; Carrington, P. J.; Krier, A.

    2014-07-28

    The optical parameters describing the sub-bandgap response of GaSb/GaAs quantum rings solar cells have been obtained from photocurrent measurements using a modulated pseudo-monochromatic light source in combination with a second, continuous photo-filling source. By controlling the charge state of the quantum rings, the photoemission cross-sections describing the two-photon sub-bandgap transitions could be determined independently. Temperature dependent photo-response measurements also revealed that the barrier for thermal hole emission from the quantum rings is significantly below the quantum ring localisation energy. The temperature dependence of the sub-bandgap photo-response of the solar cell is also described in terms of the photo- and thermal-emission characteristics of the quantum rings.

  5. The Design of a Large Booster Ring for the Medium Energy Electron-Ion Collider at Jlab

    SciTech Connect (OSTI)

    Edward Nissen, Todd Satogata, Yuhong Zhang

    2012-07-01

    In this paper, we present the current design of the large booster ring for the Medium energy Electron-Ion Collider at Jefferson Lab. The booster ring takes 3 GeV protons or ions of equivalent rigidity from a pre-booster ring, and accelerates them to 20 GeV for protons or equivalent energy for light to heavy ions before sending them to the ion collider ring. The present design calls for a figure-8 shape of the ring for superior preservation of ion polarization. The ring is made of warm magnets and shares a tunnel with the two collider rings. Acceleration is achieved by warm RF systems. The linear optics has been designed with the transition energy above the highest beam energy in the ring so crossing of transition energy will be avoided. Preliminary beam dynamics studies including chromaticity compensation are presented in this paper.

  6. Hybrid permanent magnet quadrupoles for the Recycler Ring at Fermilab

    SciTech Connect (OSTI)

    Brown, B.C.; Pruss, S.M.; Foster, G.W.; Glass, H.D.; Harding, D.J.; Jackson, G.R.; May, M.R.; Nicol, T.H.; Ostiguy, J.-F.; Schlabach, R.; Volk, J.T.

    1997-10-01

    Hybrid Permanent Magnet Quadrupoles are used in several applications for the Fermilab Recycler Ring and associated beam transfer lines. Most of these magnets use a 0.6096 m long iron shell and provide integrated gradients up to 1.4 T-m/m with an iron pole tip radius of 41.6 mm. A 58.4 mm pole radius design is also required. Bricks of 25. 4 mm thick strontium ferrite supply the flux to the back of the pole to produce the desired gradients (0.6 to 2.75 T/m). For temperature compensation, Ni-Fe alloy strips are interspersed between ferrite bricks to subtract flux in a temperature dependent fashion. Adjustments of the permeance of each pole using iron between the pole and the flux return shell permits the matching of pole potentials. Magnetic potentials of the poles are adjusted to the desired value to achieve the prescribed strength and field uniformity based on rotating coil harmonic measurements. Procurement, fabrication, pole potential adjustment, and measured fields will be reported.

  7. MCM ring hexamerization is a prerequisite for DNA-binding

    SciTech Connect (OSTI)

    Froelich, Clifford A.; Nourse, Amanda; Enemark, Eric J.

    2015-09-13

    The hexameric Minichromosome Maintenance (MCM) protein complex forms a ring that unwinds DNA at the replication fork in eukaryotes and archaea. Our recent crystal structure of an archaeal MCM N-terminal domain bound to single-stranded DNA (ssDNA) revealed ssDNA associating across tight subunit interfaces but not at the loose interfaces, indicating that DNA-binding is governed not only by the DNA-binding residues of the subunits (MCM ssDNA-binding motif, MSSB) but also by the relative orientation of the subunits. We now extend these findings to show that DNA-binding by the MCM N-terminal domain of the archaeal organism Pyrococcus furiosus occurs specifically in the hexameric oligomeric form. We show that mutants defective for hexamerization are defective in binding ssDNA despite retaining all the residues observed to interact with ssDNA in the crystal structure. One mutation that exhibits severely defective hexamerization and ssDNA-binding is at a conserved phenylalanine that aligns with the mouse Mcm4(Chaos3) mutation associated with chromosomal instability, cancer, and decreased intersubunit association.

  8. Collective Effects in a Diffraction Limited Storage Ring

    SciTech Connect (OSTI)

    Nagaoka, Ryutaro; Bane, Karl L.F.

    2015-10-20

    Our paper gives an overview of collective effects that are likely to appear and possibly limit the performance in a diffraction-limited storage ring (DLSR) that stores a high-intensity ultra-low-emittance beam. Beam instabilities and other intensity-dependent effects that may significantly impact the machine performance are covered. The latter include beam-induced machine heating, Touschek scattering, intra-beam scattering, as well as incoherent tune shifts. The general trend that the efforts to achieve ultra-low emittance result in increasing the machine coupling impedance and the beam sensitivity to instability is reviewed. The nature of coupling impedance in a DLSR is described, followed by a series of potentially dangerous beam instabilities driven by the former, such as resistive-wall, TMCI (transverse mode coupling instability), head-tail and microwave instabilities. Additionally, beam-ion and CSR (coherent synchrotron radiation) instabilities are also treated. Means to fight against collective effects such as lengthening of the bunch with passive harmonic cavities and bunch-by-bunch transverse feedback are introduced. Numerical codes developed and used to evaluate the machine coupling impedance, as well as to simulate beam instability using the former as inputs are described.

  9. The AGS Booster main ring power supply system

    SciTech Connect (OSTI)

    Soukas, A.; Hughes, K.; Sandberg, J.; Toldo, F.; Zhang, S.Y. )

    1989-01-01

    The AGS Booster is being designed as a very versatile particle accelerator. Its primary function is to be a high quality injector to the currently operating Alternating Gradient Synchrotron (AGS). The Booster/AGS combination will produce proton intensities greater than 5 {times} 10{sup 13}protons per pulse (ppp), and accelerate heavy ions, with mass up to 200, to a maximum energy of 15 GeV per atomic mass unit (GeV/amu). The power supply for the Booster Main Ring (BMRPS) has to accommodate a wide range of cycles and a wide range of operating parameters. The cycles range from storage for several seconds to rapid cycling at 7.5 Hz. The peak output power is 18 MW. This paper will describe the AGS Booster machine powering requirements, the choice of power supply, the a.c. circuit tie-in and its associated problems and some of the details of the design of the BMRPS. 9 refs., 2 figs.

  10. Spatiotemporal electromagnetic soliton and spatial ring formation in nonlinear metamaterials

    SciTech Connect (OSTI)

    Zhang Jinggui; Wen Shuangchun; Xiang Yuanjiang; Wang Youwen; Luo Hailu

    2010-02-15

    We present a systematic investigation of ultrashort electromagnetic pulse propagation in metamaterials (MMs) with simultaneous cubic electric and magnetic nonlinearity. We predict that spatiotemporal electromagnetic solitons may exist in the positive-index region of a MM with focusing nonlinearity and anomalous group velocity dispersion (GVD), as well as in the negative-index region of the MM with defocusing nonlinearity and normal GVD. The experimental circumstances for generating and manipulating spatiotemporal electromagnetic solitons can be created by elaborating appropriate MMs. In addition, we find that, in the negative-index region of a MM, a spatial ring may be formed as the electromagnetic pulse propagates for focusing nonlinearity and anomalous GVD; while the phenomenon of temporal splitting of the electromagnetic pulse may appear for the same case except for the defocusing nonlinearity. Finally, we demonstrate that the nonlinear magnetization makes the sign of effective electric nonlinear effect switchable due to the combined action of electric and magnetic nonlinearity, exerting a significant influence on the propagation of electromagnetic pulses.

  11. Electrodynamics of a ring-shaped spiral resonator

    SciTech Connect (OSTI)

    Maleeva, N.; Karpov, A.; Averkin, A.; Fistul, M. V.; Zhuravel, A. P.; Jung, P.; Ustinov, A. V.

    2014-02-14

    We present analytical, numerical, and experimental investigations of electromagnetic resonant modes of a compact monofilar Archimedean spiral resonator shaped in a ring, with no central part. Planar spiral resonators are interesting as components of metamaterials for their compact deep-subwavelength size. Such resonators couple primarily to the magnetic field component of the incident electromagnetic wave, offering properties suitable for magnetic meta-atoms. Surprisingly, the relative frequencies of the resonant modes follow the sequence of the odd numbers as f{sub 1}:f{sub 2}:f{sub 3}:f{sub 4}… = 1:3:5:7…, despite the nearly identical boundary conditions for electromagnetic fields at the extremities of the resonator. In order to explain the observed spectrum of resonant modes, we show that the current distribution inside the spiral satisfies a particular Carleman type singular integral equation. By solving this equation, we obtain a set of resonant frequencies. The analytically calculated resonance frequencies and the current distributions are in good agreement with experimental data and the results of numerical simulations. By using low-temperature laser scanning microscopy of a superconducting spiral resonator, we compare the experimentally visualized ac current distributions over the spiral with the calculated ones. Theory and experiment agree well with each other. Our analytical model allows for calculation of a detailed three-dimensional magnetic field structure of the resonators.

  12. Localized PEPII Storage Ring Optics Measurements (SULI paper)

    SciTech Connect (OSTI)

    Landy, Jonthan; /Caltech /SLAC

    2006-01-04

    The current technique employed to determine the parameters which specify the betatron oscillation in the PEPII ring at SLAC is a global procedure in that the data from each BPM (Beam Position Monitor) is weighted equally. However for more accurate interaction point (IP) measurements it would be beneficial to weight the data from the BPMs closest to the IP much more heavily. Researchers are thus considering the possibility of developing a technique to determine the oscillation parameters near the IP using as few BPMs as possible. In this paper, allowing BPM gains and cross coupling, we show analytically that given data from N BPMs there remain 6N + 2 degrees of freedom in the matrices M{sub A,A}, M{sub B,A}, ..., M{sub N,N-1} unspecified by the observable data alone. From this we demonstrate that data from at least 3 BPMs is required to completely specify the system when the transfer maps between BPMs are assumed known, and that 4 BPMs may be more suitable.

  13. Collective Effects in a Diffraction Limited Storage Ring

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

    Nagaoka, Ryutaro; Bane, Karl L.F.

    2015-10-20

    Our paper gives an overview of collective effects that are likely to appear and possibly limit the performance in a diffraction-limited storage ring (DLSR) that stores a high-intensity ultra-low-emittance beam. Beam instabilities and other intensity-dependent effects that may significantly impact the machine performance are covered. The latter include beam-induced machine heating, Touschek scattering, intra-beam scattering, as well as incoherent tune shifts. The general trend that the efforts to achieve ultra-low emittance result in increasing the machine coupling impedance and the beam sensitivity to instability is reviewed. The nature of coupling impedance in a DLSR is described, followed by a seriesmore » of potentially dangerous beam instabilities driven by the former, such as resistive-wall, TMCI (transverse mode coupling instability), head-tail and microwave instabilities. Additionally, beam-ion and CSR (coherent synchrotron radiation) instabilities are also treated. Means to fight against collective effects such as lengthening of the bunch with passive harmonic cavities and bunch-by-bunch transverse feedback are introduced. Numerical codes developed and used to evaluate the machine coupling impedance, as well as to simulate beam instability using the former as inputs are described.« less

  14. MCM ring hexamerization is a prerequisite for DNA-binding

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

    Froelich, Clifford A.; Nourse, Amanda; Enemark, Eric J.

    2015-09-13

    The hexameric Minichromosome Maintenance (MCM) protein complex forms a ring that unwinds DNA at the replication fork in eukaryotes and archaea. Our recent crystal structure of an archaeal MCM N-terminal domain bound to single-stranded DNA (ssDNA) revealed ssDNA associating across tight subunit interfaces but not at the loose interfaces, indicating that DNA-binding is governed not only by the DNA-binding residues of the subunits (MCM ssDNA-binding motif, MSSB) but also by the relative orientation of the subunits. We now extend these findings to show that DNA-binding by the MCM N-terminal domain of the archaeal organism Pyrococcus furiosus occurs specifically in themore » hexameric oligomeric form. We show that mutants defective for hexamerization are defective in binding ssDNA despite retaining all the residues observed to interact with ssDNA in the crystal structure. One mutation that exhibits severely defective hexamerization and ssDNA-binding is at a conserved phenylalanine that aligns with the mouse Mcm4(Chaos3) mutation associated with chromosomal instability, cancer, and decreased intersubunit association.« less

  15. METALLIZATION OF SNS RING INJECTION KICKER CERAMIC CHAMBERS.

    SciTech Connect (OSTI)

    HE,P.; HSEUH,H.C.; TODD,R.J.

    2002-06-03

    Ceramic chambers will be used in the pulsed kicker magnets for the injection of H{sup -} into the Spallation Neutron Source (SNS) accumulator ring, to avoid shielding of a fast-changing external magnetic field by metallic chamber walls and to reduce eddy current heating. The inner surfaces of the ceramic chambers will be coated with a conductive layer, possibly titanium (Ti) or copper (Cu) with a titanium nitride (TiN) overlayer, to reduce the beam coupling impedance, provide passage for beam image current and to reduce the secondary electron yields. This paper describes the development of sputtering method for the 0.83m long 16cm inner diameter (ID) ceramic chambers. Coatings of Ti, Cu and TiN with thickness up to 10 {micro}m were produced by means of DC magnetron sputtering. The difficulty of coating insulators was overcome with the introduction of an anode screen. Films with good adhesion, uniform longitudinal thickness, and conductivity were produced.

  16. Outgassing rate of Reemay Spunbonded Polyester and DuPont Double Aluminized Mylar

    SciTech Connect (OSTI)

    Todd, R.J.; Pate, D.; Welch, K.M.

    1993-08-01

    This paper presents the outgassing rates of two commercially available multi-layer insulation (MLI) materials commonly used in cryogenic applications. Both Reemay Spunbonded Polyester and DuPont Double Aluminized Mylar (DAM) were studied for outgassing species and respective rates, and the total amount of outgassed material. Measurements were made using a Fixed Aperture Technique. A sample was pumped on through an aperture of known size with a turbomolecular pump. Pressure vs. time was plotted for both Reemay and DAM, as well as the baseline system, and data conveniently extrapolated to {approx}1,000 hrs. A quadrupole residual gas analyzer was used to measure the outgassing species.

  17. DuPont Displays Develops Low-Cost Method of Printing OLED Panels

    Office of Energy Efficiency and Renewable Energy (EERE)

    DuPont Displays Inc. (DDI) has developed a novel way of printing color-tunable OLED lighting panels that keeps manufacturing costs low. The method involves processing the organic layers from solution, with most of the process steps taking place under atmospheric conditions rather than in a high vacuum. Industry-standard slot-coating methods are used in conjunction with nozzle printing—in which the solutions of organic materials are continuously jetted through an array of nozzles moving at high speed—allowing the light-emitting materials to be spatially patterned.

  18. Lac du Flambeau Band of Lake Superior Chippewa Indians Strategic Energy Plan

    SciTech Connect (OSTI)

    Bryan Hoover

    2009-11-16

    This plan discusses the current energy use on the Lac du Flambeau Reservation, the current status of the Tribe's energy program, as well as the issues and concerns with energy on the reservation. This plan also identifies and outlines energy opportunities, goals, and objectives for the Tribe to accomplish. The overall goal of this plan is to address the energy situation of the reservation in a holistic manner for the maximum benefit to the Tribe. This plan is an evolving document that will be re-evaluated as the Tribe's energy situation changes.

  19. DOE - Office of Legacy Management -- E I Du Pont Grasselli Plant - OH 03

    Office of Legacy Management (LM)

    Grasselli Plant - OH 03 FUSRAP Considered Sites Site: E.I. Du Pont, Grasselli Plant (OH.03 ) Eliminated from consideration under FUSRAP Designated Name: Not Designated Alternate Name: Grasselli Laboratories Standard Oil Company of Ohio OH.03-1 OH.03-2 Location: 3092 Broadway Avenue , Cleveland , Ohio OH.03-4 Evaluation Year: 1985 OH.03-3 Site Operations: Tested processes for jacketing uranium slugs with zinc, aluminum, silicon and brass in the 1940s OH.03-5 OH.03-6 Site Disposition: Eliminated -

  20. Ami M. DuBois, John David Lee, and Abdulgadar F. Almagri

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

    high time resolution x-ray diagnostic on the Madison Symmetric Torus Ami M. DuBois, John David Lee, and Abdulgadar F. Almagri Citation: Review of Scientific Instruments 86, 073512 (2015); doi: 10.1063/1.4927454 View online: http://dx.doi.org/10.1063/1.4927454 View Table of Contents: http://scitation.aip.org/content/aip/journal/rsi/86/7?ver=pdfcov Published by the AIP Publishing Articles you may be interested in Upgrades of imaging x-ray crystal spectrometers for high-resolution and

  1. Lac du Flambeau Band of Lake Superior Chippewa Indians - Conservation and Renewable Energy Planning

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

    Bryan Hoover Lac du Flambeau Band of Lake Superior Chippewa Indians November 20, 2008 * Located in North Central Wisconsin. * The reservation is 144 square miles or 86,000 acres. * Population 3,400 Tribal Members. * Checkerboard Reservation * Area- 86,630 acres or 144 square miles * Land Ownership- 66.8%-Tribal land 33.2%-Fee land * 260 Lakes * 71 Miles of Streams * 24,000 Acres of Wetlands * 41,733 Acres of Forests * Develop and evaluate baseline data on energy consumption, costs, trends and

  2. Radiation densitometry in tree-ring analysis: a review and procedure manual

    SciTech Connect (OSTI)

    Parker, M.L.; Taylor, F.G.; Doyle, T.W.; Foster, B.E.; Cooper, C.; West, D.C.

    1985-01-01

    An x-ray densitometry of wood facility is being established by the Environmental Sciences Division, Oak Ridge Natioanl Laboratory (ORNL). The objective is to apply tree-ring data to determine whether or not there is a fertilizer effect on tree growth from increased atmospheric carbon dioxide since the beginning of the industrial era. Intra-ring width and density data, including ring-mass will be detemined from tree-ring samples collected from sites located throughout the United States and Canada. This report is designed as a guide to assist ORNL scientists in building the x-ray densitometry system. The history and development of x-ray densitometry in tree-ring research is examined and x-ray densitometry is compared with other techniques. Relative wood and tree characteristics are described as are environmental and genetic factors affecting tree growth responses. Methods in x-ray densitometry are examined in detail and the techniques used at four operating laboratories are described. Some ways that dendrochronology has been applied in dating, in wood quality, and environmental studies are presented, and a number of tree-ring studies in Canada are described. An annotated bibliography of radiation densitometry in tree-ring analysis and related subjects is included.

  3. Mixing characteristics of compressible vortex rings interacting with normal shock waves

    SciTech Connect (OSTI)

    Cetegen, B.M. . Mechanical Engineering Dept.); Hermanson, J.C. )

    1995-01-01

    Current interest in the interaction between compressible vortical flows and shock waves is largely motivated by the need to promote rapid, loss-effective mixing and combustion of hydrogen and hydrocarbon fuels for supersonic combustor applications. The instability mechanisms and mixing enhancement arising from the interaction of a compressible vortex ring with a normal shock wave were studied in a colinear, dual-shock tube. This flow geometry simulates features of the interaction of a shock wave with a jet containing streamwise vorticity, a configuration of significant interest for supersonic combustion applications. Flow visualization and quantitative concentration measurements were performed by planar laser Rayleigh scattering. For a given primary shock strength, interfacial instability is more evident in a weak vortex ring than in a strong vortex ring. In all cases, the identity of the vortex ring is lost after a sufficiently long time of interaction. The probability density function of the mixed fluid changes rapidly from a bimodal distribution to a single peak upon processing by a shock wave. The most probable concentration decreases with time, indicating a rapid increase in mixing and dilution of the vortex fluid. The mixing enhancement is most rapid for the case of a strong vortex ring interacting with a strong shock wave, somewhat slower for a weak vortex ring and a strong shock wave, and significantly slower for the case of a strong vortex ring and a weaker shock wave. These observations are consistent with the earlier numerical predictions.

  4. "Ring opening" article selected as royal society of chemistry hot topic

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

    "Ring opening" article selected as royal society of chemistry hot topic An article authored by Los Alamos staff John C. Gordon (Chemistry) and Louis "Pete" Silks (Bioscience) on the opening hydrocarbon rings in biomass-derived furan has been selected as a hot topic by Royal Society of Chemistry (RSC) publishing. The article describes ongoing work by Gordon, Silks, and colleagues. The work investigates a method of opening biomass-derived furan rings under mild conditions and

  5. Characterization of supernumerary ring marker chromosomes by fluorescence in situ hybridization (FISH)

    SciTech Connect (OSTI)

    Blennow, E.; Nordenskjoeld, M. ); Asadi, E. ); Anneren, G.; Berggren, E.; Nordenskjoeld, M.

    1993-08-01

    Five cases with small supernumerary ring chromosomes are characterized at the molecular level. Routine chromosome banding analysis was insufficient for identification of the ring chromosomes, and none of them was DA/DAPI positive. Fluorescence in situ hybridization utilizing repetitive centromeric probes for all chromosomes has determined that one of these five ring chromosomes originates in each of chromosomes 4, 7, 8, 9, and 20. Chromosome painting with chromosome-specific libraries has confirmed this and excluded the involvement of additional chromosomes in the rearrangements. 30 refs., 3 figs., 2 tabs.

  6. Mesoscopic Kondo Screening Effect in a Single-Electron Transistor Embedded in a Metallic Ring

    SciTech Connect (OSTI)

    Hu, Hui; Zhang, Guang-Ming; Yu, Lu

    2001-06-11

    We study the Kondo screening effect generated by a single-electron transistor or quantum dot embedded in a small metallic ring. When the ring circumference L becomes comparable to the fundamental length scale {xi}{sup 0}{sub K}={Dirac_h}{upsilon}{sub F}/ T{sup 0}{sub K} associated with the bulk Kondo temperature, the Kondo resonance is strongly affected, depending on the total number of electrons (mod4) and magnetic flux threading the ring. The resulting Kondo-assisted persistent currents are also calculated in both Kondo and mixed-valence regimes, and the maximum values are found in the crossover region.

  7. CSR in the SuperKEKB Damping Ring (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    It can degrade the beam quality in both storage rings and linacs through enhancing the ... Resource Type: Conference Resource Relation: Journal Name: Conf.Proc.C100523:TUPEB018,2010...

  8. The ITER pre-compression rings – A first in cryogenic composite technology

    SciTech Connect (OSTI)

    Rajainmaki, Hannu; Fanthome, John; Losasso, Marcello; Rodriguez, Jesus; Evans, David; Diaz, Victor

    2014-01-27

    The ITER Pre-Compression Rings represent one of the heaviest composite structures ever manufactured as a single piece and the largest - the outer diameter will be above 5.5 meters - intended for use in a cryogenic environment. With a cross section of 337 mm × 288 mm, each item will weigh more than 3,000 kg. A development program, based on filament wound and dry wound S2 glass unidirectional fibers, the latter processed by VARTM, was completed on one fifth scale rings, and these materials and techniques were shown to be satisfactory. The paper describes how a technology applied to build up primary structures of European launchers is being accommodated to produce the ITER Pre-Compression Rings, fulfilling its extremely challenging requirements. In addition, we will describe how the structural analysis is correlated with the test results of scaled down rings, as well as how the pre-compression rings’ manufacturing process will be qualified.

  9. PEP-X: An Ultimate Storage Ring Based on Fourth-Order Geometric...

    Office of Scientific and Technical Information (OSTI)

    document is also available for sale to the public from the National Technical Information Service, Springfield, VA at www.ntis.gov. We have designed an 'ultimate' storage ring for...

  10. Ion Effects in the PEP-II High Energy Ring (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    the expected ion effects in the PEP-II High Energy Ring, considering both a uniform vacuum pressure and a local pressure bump in the IR quadrupoles. Authors: Zimmermann, Frank...

  11. Status of the MEIC ion collider ring design (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    ring design You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information ...

  12. Investigation into electron cloud effects in the International Linear Collider positron damping ring

    SciTech Connect (OSTI)

    Crittenden, J.A.; Conway, J.; Dugan, G.F.; Palmer, M.A.; Rubin, D.L.; Shanks, J.; Sonnad, K.G.; Boon, L.; Harkay, K.; Ishibashi, T.; Furman, M.A.; Guiducci, S.; Pivi, M.T.F.; Wang, L.; Crittenden, J.A.; Conway, J.; Dugan, G.F.; Palmer, M.A.; Rubin, D.L.; Shanks, J.; Sonnad, K.G.; Boon, L.; Harkay, K.; Ishibashi, T.; Furman, M.A.; Guiducci, S.; Pivi, M.T.F.; Wang, L.

    2014-02-28

    We report modeling results for electron cloud buildup and instability in the International Linear Collider positron damping ring. Updated optics, wiggler magnets, and vacuum chamber designs have recently been developed for the 5 GeV, 3.2-km racetrack layout. An analysis of the synchrotron radiation profile around the ring has been performed, including the effects of diffuse and specular photon scattering on the interior surfaces of the vacuum chamber. The results provide input to the cloud buildup simulations for the various magnetic field regions of the ring. The modeled cloud densities thus obtained are used in the instability threshold calculations. We conclude that the mitigation techniques employed in this model will suffice to allow operation of the damping ring at the design operational specifications

  13. A Test Facility for MEIC ERL Circulator Ring Based Electron Cooler...

    Office of Scientific and Technical Information (OSTI)

    repetition rate up to 750 MHz is required for MEIC. The present cooler design concept is based on a magnetized photo-cathode SRF gun, an SRF ERL and a compact circulator ring. ...

  14. Cell culture arrays using micron-sized ferromagnetic ring-shaped thin films

    SciTech Connect (OSTI)

    Huang, Chen-Yu; Wei, Zung-Hang; Lai, Mei-Feng; Ger, Tzong-Rong

    2015-05-07

    Cell patterning has become an important technology for tissue engineering. In this research, domain walls are formed at the two ends of a ferromagnetic ring thin film after applying a strong external magnetic field, which can effectively attract magnetically labeled cells and control the position for biological cell. Magnetophoresis experiment was conducted to quantify the magnetic nanoparticle inside the cells. A ring-shaped magnetic thin films array was fabricated through photolithography. It is observed that magnetically labeled cells can be successfully attracted to the two ends of the ring-shaped magnetic thin film structure and more cells were attracted and further attached to the structures. The cells are co-cultured with the structure and kept proliferating; therefore, such ring thin film can be an important candidate for in-vitro biomedical chips or tissue engineering.

  15. Transition-Metal-Centered Nine-Membered Boron Rings: M©B 9 and...

    Office of Scientific and Technical Information (OSTI)

    We report the observation of two transition-metal-centered nine-atom boron rings, RhB9 - and IrB9-. These two doped-boron clusters are produced in a laser-vaporization ...

  16. SEVENTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    SciTech Connect (OSTI)

    Daugherty, W.

    2012-08-30

    A series of experiments to monitor the aging performance of Viton GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. Seventy tests using mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 F. They were leak-tested initially and have been tested periodically to determine if they meet the criterion of leak-tightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 F. High temperature aging continues for 23 GLT O-ring fixtures at 200 270 F. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 F and higher temperatures, and in 8 fixtures aging at 300 F. The remaining GLT O-ring fixtures aging at 300 F have been retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 F for 54-72 months, which is still bounding to O-ring temperatures during storage in K-Area Complex (KAC). Based on expectations that the fixtures aging at 200 F will remain leak-tight for a significant period yet to come, 2 additional fixtures began aging in 2011 at an intermediate temperature of 270 F, with hopes that they may reach a failure condition before the 200 F fixtures. High temperature aging continues for 6 GLT-S O-ring fixtures at 200 300 F. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 F. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 - 300 F for 30 - 36 months. For O-ring fixtures that have failed the room temperature leak test and been disassembled, the O-rings displayed a compression set ranging from 51 96%. This is greater than seen to date for any packages inspected during KAC field surveillance (24

  17. The eddy-current technique for nondestructive evaluation of generator retaining rings: Feasibility study: Interim report

    SciTech Connect (OSTI)

    Elmo, P.M.; Nottingham, L.D.

    1988-05-01

    An evaluation of the feasibility of using eddy current nondestructive inspection techniques to detect intergranular stress corrosion in generator rotor retaining rings was conducted by the EPRI NDE Center. Experiments were conducted using a bend-bar containing representative stress corrosion damage, a calibration block containing electrical discharge machined (EDM) notches, and four retired retaining rings containing EDM notches and stress corrosion damage. An eddy current transducer transport was designed and fabricated to interface with an existing computer-controlled, two-axis positioner and digital eddy current data acquisition system. Test results of experiments performed with this equipment on the retaining ring test-bed provided experimental validation of the eddy current method's feasibility as a retaining ring inspection method. Details are given of the system and its performance under laboratory and simulated service-inspection conditions. 9 refs., 47 figs.

  18. The two-way relationship between ionospheric outflow and the ring current

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

    Welling, Daniel T.; Jordanova, Vania Koleva; Glocer, Alex; Toth, Gabor; Liemohn, Michael W.; Weimer, Dan R.

    2015-06-01

    It is now well established that the ionosphere, because it acts as a significant source of plasma, plays a critical role in ring current dynamics. However, because the ring current deposits energy into the ionosphere, the inverse may also be true: the ring current can play a critical role in the dynamics of ionospheric outflow. This study uses a set of coupled, first-principles-based numerical models to test the dependence of ionospheric outflow on ring current-driven region 2 field-aligned currents (FACs). A moderate magnetospheric storm event is modeled with the Space Weather Modeling Framework using a global MHD code (Block Adaptivemore » Tree Solar wind Roe-type Upwind Scheme, BATS-R-US), a polar wind model (Polar Wind Outflow Model), and a bounce-averaged kinetic ring current model (ring current atmosphere interaction model with self-consistent magnetic field, RAM-SCB). Initially, each code is two-way coupled to all others except for RAM-SCB, which receives inputs from the other models but is not allowed to feed back pressure into the MHD model. The simulation is repeated with pressure coupling activated, which drives strong pressure gradients and region 2 FACs in BATS-R-US. It is found that the region 2 FACs increase heavy ion outflow by up to 6 times over the non-coupled results. The additional outflow further energizes the ring current, establishing an ionosphere-magnetosphere mass feedback loop. This study further demonstrates that ionospheric outflow is not merely a plasma source for the magnetosphere but an integral part in the nonlinear ionosphere-magnetosphere-ring current system.« less

  19. Assembling a ring-shaped crystal in a microfabricated surface ion trap

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

    Stick, Daniel Lynn; Univ. of New Mexico, Albuquerque, NM; Tabakov, Boyan; Univ. of New Mexico, Albuquerque, NM; Benito, Francisco; Blain, Matthew; Clark, Craig R.; Clark, Susan; Haltli, Raymond A.; Maunz, Peter; et al

    2015-09-01

    We report on experiments with a microfabricated surface trap designed for confining a chain of ions in a ring. Uniform ion separation over most of the ring is achieved with a rotationally symmetric design and by measuring and suppressing undesired electric fields. After reducing stray fields, the ions are confined primarily by a radio-frequency pseudopotential and their mutual Coulomb repulsion. As a result, approximately 400 40Ca+ ions with an average separation of 9 μm comprise the ion crystal.

  20. Simulation of Bunch Lengthening and Sawtooth Mode in the SLAC Damping Rings

    SciTech Connect (OSTI)

    Warnock, Robert L.

    2000-06-29

    The authors study longitudinal coherent motion of a stored electron beam by a time domain integration of the nonlinear Vlasov-Fokker-Planck equation. For the present SLAC damping rings the authors found several features in agreement with experiment. This report emphasizes the earlier vacuum chamber of the rings, replaced in 1992--93. Nonlinear effects are much stronger for the old chamber, and the computed phenomena more various.

  1. The two-way relationship between ionospheric outflow and the ring current

    SciTech Connect (OSTI)

    Welling, Daniel T.; Jordanova, Vania Koleva; Glocer, Alex; Toth, Gabor; Liemohn, Michael W.; Weimer, Dan R.

    2015-06-01

    It is now well established that the ionosphere, because it acts as a significant source of plasma, plays a critical role in ring current dynamics. However, because the ring current deposits energy into the ionosphere, the inverse may also be true: the ring current can play a critical role in the dynamics of ionospheric outflow. This study uses a set of coupled, first-principles-based numerical models to test the dependence of ionospheric outflow on ring current-driven region 2 field-aligned currents (FACs). A moderate magnetospheric storm event is modeled with the Space Weather Modeling Framework using a global MHD code (Block Adaptive Tree Solar wind Roe-type Upwind Scheme, BATS-R-US), a polar wind model (Polar Wind Outflow Model), and a bounce-averaged kinetic ring current model (ring current atmosphere interaction model with self-consistent magnetic field, RAM-SCB). Initially, each code is two-way coupled to all others except for RAM-SCB, which receives inputs from the other models but is not allowed to feed back pressure into the MHD model. The simulation is repeated with pressure coupling activated, which drives strong pressure gradients and region 2 FACs in BATS-R-US. It is found that the region 2 FACs increase heavy ion outflow by up to 6 times over the non-coupled results. The additional outflow further energizes the ring current, establishing an ionosphere-magnetosphere mass feedback loop. This study further demonstrates that ionospheric outflow is not merely a plasma source for the magnetosphere but an integral part in the nonlinear ionosphere-magnetosphere-ring current system.

  2. Instability suppression of clusters of vector-necklace-ring solitons in nonlocal media

    SciTech Connect (OSTI)

    Shen Ming; Kong Qian; Jeng, Chien-Chung; Ge Lijuan; Lee, Ray-Kuang; Krolikowski, Wieslaw

    2011-02-15

    We study the instability suppression of vector-necklace-ring soliton clusters carrying zero, integer, and fractional angular momentums in nonlocal nonlinear media with an arbitrary degree of nonlocality. We show that the combination of nonlocality and mutual trapping of soliton constituent components can completely stabilize the vector-necklace-ring soliton clusters which are otherwise only quasistable in local media. Our results may be useful to studies of the novel soliton states in Bose-Einstein with dipolar long-range interactions.

  3. Two Nerds . . . One Love . . . and A Great Golden Ring | Department of

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

    Energy Nerds . . . One Love . . . and A Great Golden Ring Two Nerds . . . One Love . . . and A Great Golden Ring August 17, 2011 - 4:26pm Addthis Two scientists got engaged in the Relativistic Heavy Ion Collider at Brookhaven National Laboratory in New York. | Video from The Daily Charles Rousseaux Charles Rousseaux Senior Communications Specialist (detailee) The work of the Energy Department has led to many scientific and technological breakthroughs. Today, we're highlighting a different

  4. Double-stator electromagnetic pump having alignment ring and spine assembly

    DOE Patents [OSTI]

    Fanning, A.W.; Olich, E.E.; Dahl, L.R.; Patel, M.R.

    1997-06-24

    A support structure for clamping the inner coils and inner lamination rings of an inner stator column of an electromagnetic induction pump to prevent damaging vibration is disclosed. A spine assembly, including a base plate, a center post and a plurality of ribs, serves as the structural frame for the inner stator. Stacked alignment rings provide structure to the lamination rings and locate them concentrically around the spine assembly central axis. The alignment rings are made of a material having a high thermal expansion coefficient to compensate for the lower expansion of the lamination rings and, overall, provide an approximate match to the expansion of the inner flow duct. The net result is that the radial clamping provided by the duct around the stator iron is maintained (approximately) over a range of temperatures and operating conditions. Axial clamping of the inner stator structure is achieved via tie rods which run through grooves in the ribs and engage the base plate at the bottom of the inner stator and engage a clamping plate at the top. Slender tie rods and a flexible clamping plate are used to provide compliance in the axial clamping system to accommodate differential thermal growth (axially) between the tie rods and lamination ring elements without losing clamping force. 12 figs.

  5. Double-stator electromagnetic pump having alignment ring and spine assembly

    DOE Patents [OSTI]

    Fanning, Alan Wayne; Olich, Eugene Ellsworth; Dahl, Leslie Roy; Patel, Mahadeo Ratilal

    1997-01-01

    A support structure for clamping the inner coils and inner lamination rings of an inner stator column of an electromagnetic induction pump to prevent damaging vibration. A spine assembly, including a base plate, a center post and a plurality of ribs, serves as the structural frame for the inner stator. Stacked alignment rings provide structure to the lamination rings and locate them concentrically around the spine assembly central axis. The alignment rings are made of a material having a high thermal expansion coefficient to compensate for the lower expansion of the lamination rings and, overall, provide an approximate match to the expansion of the inner flow duct. The net result is that the radial clamping provided by the duct around the stator iron is maintained (approximately) over a range of temperatures and operating conditions. Axial clamping of the inner stator structure is achieved via tie rods which run through grooves in the ribs and engage the base plate at the bottom of the inner stator and engage a clamping plate at the top. Slender tie rods and a flexible clamping plate are used to provide compliance in the axial clamping system to accommodate differential thermal growth (axially) between the tie rods and lamination ring elements without losing clamping force.

  6. Capture, acceleration and bunching rf systems for the MEIC booster and storage rings

    SciTech Connect (OSTI)

    Wang, Shaoheng; Guo, Jiquan; Lin, Fanglei; Morozov, Vasiliy; Rimmer, Robert A.; Wang, Haipeng; Zhang, Yuhong

    2015-09-01

    The Medium-energy Electron Ion Collider (MEIC), proposed by Jefferson Lab, consists of a series of accelerators. The electron collider ring accepts electrons from CEBAF at energies from 3 to 12 GeV. Protons and ions are delivered to a booster and captured in a long bunch before being ramped and transferred to the ion collider ring. The ion collider ring accelerates a small number of long ion bunches to colliding energy before they are re-bunched into a high frequency train of very short bunches for colliding. Two sets of low frequency RF systems are needed for the long ion bunch energy ramping in the booster and ion collider ring. Another two sets of high frequency RF cavities are needed for re-bunching in the ion collider ring and compensating synchrotron radiation energy loss in the electron collider ring. The requirements from energy ramping, ion beam bunching, electron beam energy compensation, collective effects, beam loading and feedback capability, RF power capability, etc. are presented. The preliminary designs of these RF systems are presented. Concepts for the baseline cavity and RF station configurations are described, as well as some options that may allow more flexible injection and acceleration schemes.

  7. NINTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    SciTech Connect (OSTI)

    Daugherty, W.

    2014-08-06

    A series of experiments to monitor the aging performance of Viton GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. One approach has been to periodically evaluate the leak performance of O-rings being aged in mock-up 9975 Primary Containment Vessels (PCVs) at elevated temperatures. Other methods such as compression-stress relaxation (CSR) tests and field surveillance are also on-going to evaluate O-ring behavior. Seventy tests using PCV mock-ups were assembled and heated to temperatures ranging from 200 to 450 F. They were leak-tested initially and have been tested periodically to determine if they continue to meet the leak-tightness criterion defined in ANSI standard N14.5-97. Due to material substitution, fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 F. High temperature aging continues for 23 GLT O-ring fixtures at 200 270 F. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 F and higher temperatures, and in 8 fixtures aging at 300 F. The earliest 300 F GLT O-ring fixture failure was observed at 34 months. The remaining GLT O-ring fixtures aging at 300 F have been retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 F for 72 - 96 months, which bounds O-ring temperatures anticipated during storage in K-Area Complex (KAC). Based on expectations that the 200 F fixtures will remain leak-tight for a significant period yet to come, 2 additional fixtures began aging in 2011 at 270 F, with hopes that they may reach a failure condition before the 200 F fixtures, thus providing additional time to failure data. High temperature aging continues for 6 GLT-S O-ring fixtures at 200 300 F. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring

  8. REPLY TO AllNOF: EM-421 SUBJECT: The File TO: Elimination of the DuBois Chemical Company Site from FUSRAP

    Office of Legacy Management (LM)

    q.w -' -fihsw+P 8063 6H-j DOEF 1325.8 . 8 @w - bnited States Government - Department of Energy memorandum DATE: DEC 14 1990 REPLY TO AllNOF: EM-421 SUBJECT: The File TO: Elimination of the DuBois Chemical Company Site from FUSRAP I have reviewed the attached preliminary site summary and recommendation for the DuBois Chemical Company site in Cincinnati. I have determined that there is little likelihood of contamination at this site. Based on the above, the DuBois Chemical Company Site is hereby

  9. EIGHTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    SciTech Connect (OSTI)

    Daugherty, W. L.

    2013-09-03

    A series of experiments to monitor the aging performance of Viton GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. Seventy tests using mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 F. They were leak-tested initially and have been tested periodically to determine if they meet the criterion of leak-tightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 F. High temperature aging continues for 23 GLT O-ring fixtures at 200 270 F. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 F and higher temperatures, and in 8 fixtures aging at 300 F. The remaining GLT O-ring fixtures aging at 300 F have been retired from testing following more than 5 years at temperature without failure. No failures have yet been observed in GLT O-ring fixtures aging at 200 F for 61 - 85 months, which is still bounding to O-ring temperatures during storage in KArea Complex (KAC). Based on expectations that the fixtures aging at 200 F will remain leaktight for a significant period yet to come, 2 additional fixtures began aging in 2011 at an intermediate temperature of 270 F, with hopes that they may reach a failure condition before the 200 F fixtures. High temperature aging continues for 6 GLT-S O-ring fixtures at 200 300 F. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 F. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 - 300 F for 41 - 45 months. Aging and periodic leak testing will continue for the remaining PCV fixtures.

  10. Energy transfer between a passing vortex ring and a flexible plate in an ideal quiescent fluid

    SciTech Connect (OSTI)

    Hu, JiaCheng; Peterson, Sean D.; Porfiri, Maurizio

    2015-09-21

    Recent advancements in highly deformable smart materials have lead to increasing interest in small-scale energy harvesting research for powering low consumption electronic devices. One such recent experimental study by Goushcha et al. explored energy harvesting from a passing vortex ring by a cantilevered smart material plate oriented parallel to and offset from the path of the ring in an otherwise quiescent fluid. The present study focuses on modeling this experimental study using potential flow to facilitate optimization of the energy extraction from the passing ring to raise the energy harvesting potential of the device. The problem is modeled in two-dimensions with the vortex ring represented as a pair of counter-rotating free vortices. Vortex pair parameters are determined to match the convection speed of the ring in the experiments, as well as the imposed pressure loading on the plate. The plate is approximated as a Kirchhoff-Love plate and represented as a finite length vortex sheet in the fluid domain. The analytical model matches experimental measurements, including the tip displacement, the integrated force along the entire plate length as a function of vortex ring position, and the pressure along the plate. The potential flow solution is employed in a parametric study of the governing dimensionless parameters in an effort to guide the selection of plate properties for optimal energy harvesting performance. Results of the study indicate an optimal set of plate properties for a given vortex ring configuration, in which the time-scale of vortex advection matches that of the plate vibration.

  11. SIXTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE

    SciTech Connect (OSTI)

    Daugherty, W.

    2011-08-31

    A series of experiments to monitor the aging performance of Viton{reg_sign} GLT O-rings used in the Model 9975 package has been ongoing for seven years at the Savannah River National Laboratory. Seventy tests using mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 F. They were leak-tested initially and have been tested periodically to determine if they meet the criterion of leak-tightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 F. High temperature aging continues for 33 GLT O-ring fixtures at 200-300 F. Room temperature leak test failures have been experienced in all of the GLT O-ring fixtures aging at 350 F and higher temperatures, and in 7 fixtures aging at 300 F. No failures have yet been observed in GLT O-ring fixtures aging at 200 F for 41-60 months, which is still bounding to O-ring temperatures during storage in K-Area Complex (KAC). Based on expectations that the fixtures aging at 200 F will remain leak-tight for a significant period yet to come, 2 additional fixtures began aging within the past year at an intermediate temperature of 270 F, with hopes that they may leak before the 200 F fixtures. High temperature aging continues for 6 GLT-S O-ring fixtures at 200-300 F. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 F. No failures have yet been observed in GLT-S O-ring fixtures aging at 200-300 F for up to 26 months. For O-ring fixtures that have failed the room temperature leak test and been disassembled, the Orings displayed a compression set ranging from 51-96%. This is greater than seen to date for packages inspected during KAC field surveillance (24% average). For GLT O-rings, separate service life estimates have been made based on the O-ring fixture leak test data and based on compression stress relaxation

  12. Interactions of Jet Fuels with Nitrile O-Rings: Petroleum-Derived versus Synthetic Fuels

    SciTech Connect (OSTI)

    Gormley, R.J.; Link, D.D.; Baltrus, J.P.; Zandhuis, P.H.

    2008-01-01

    A transition from petroleum-derived jet fuels to blends with Fischer-Tropsch (F-T) fuels, and ultimately fully synthetic hydro-isomerized F-T fuels has raised concern about the fate of plasticizers in nitrile-butadiene rubber o-rings that are contacted by the fuels as this transition occurs. The partitioning of plasticizers and fuel molecules between nitrile o-rings and petroleum-derived, synthetic, and additized-synthetic jet fuels has been measured. Thermal desorption of o-rings soaked in the various jet fuels followed by gas chromatographic analysis with a mass spectrometric detector showed many of the plasticizer and stabilizer compounds were removed from the o-rings regardless of the contact fuel. Fuel molecules were observed to migrate into the o-rings for the petroleum-derived fuel as did both the fuel and additive for a synthetic F-T jet fuel additized with benzyl alcohol, but less for the unadditized synthetic fuel. The specific compounds or classes of compounds involved in the partitioning were identified and a semiquantitative comparison of relative partitioning of the compounds of interest was made. The results provide another step forward in improving the confidence level of using additized, fuIly synthetic jet fuel in the place of petroleum-derived fueL

  13. Interactions of Jet Fuels with Nitrile O-Rings: Petroleum-Derived versus Synthetic Fuels

    SciTech Connect (OSTI)

    Gormley, R.J.; Link, D.D.; Baltrus, J.P.; Zandhuis, P.H.

    2009-01-01

    A transition from petroleum-derived jet fuels to blends with Fischer-Tropsch (F-T) fuels, and ultimately fully synthetic hydro-isomerized F-T fuels has raised concern about the fate of plasticizers in nitrile-butadiene rubber a-rings that are contacted by the fuels as this transition occurs. The partitioning of plasticizers and fuel molecules between nitrile a-rings and petroleum-derived, synthetic, and additized-synthetic jet fuels has been measured. Thermal desorption of o-rings soaked in the various jet fuels followed by gas chromatographic analysis with a mass spectrometric detector showed many of the plasticizer and stabilizer compounds were removed from the o-rings regardless of the contact fuel. Fuel molecules were observed to migrate into the o-rings for the petroleum-derived fuel as did both the fuel and additive for a synthetic F-T jet fuel additized with benzyl alcohol, but less for the unadditized synthetic fuel. The specific compounds or classes of compounds involved in the partitioning were identified and a semiquantitative comparison of relative partitioning of the compounds of interest was made. The results provide another step forward in improving the confidence level of using additized, fully synthetic jet fuel in the place of petroleum-derived fuel.

  14. Feasibility Study of Compact Gas-Filled Storage Ring for 6D Cooling of Muon Beams

    SciTech Connect (OSTI)

    A. Garren, J. Kolonlo

    2005-10-31

    The future of elementary particle physics in the USA depends in part on the development of new machines such as the International Linear Collider, Muon Collider and Neutrino Factories which can produce particle beams of higher energy, intensity, or particle type than now exists. These beams will enable the continued exploration of the world of elementary particles and interactions. In addition, the associated development of new technologies and machines such as a Muon Ring Cooler is essential. This project was to undertake a feasibility study of a compact gas-filled storage ring for 6D cooling of muon beams. The ultimate goal, in Phase III, was to build, test, and operate a demonstration storage ring. The preferred lattice for the storage ring was determined and dynamic simulations of particles through the lattice were performed. A conceptual design and drawing of the magnets were made and a study of the RF cavity and possible injection/ejection scheme made. Commercial applications for the device were investigated and the writing of the Phase II proposal completed. The research findings conclude that a compact gas-filled storage ring for 6D cooling of muon beams is possible with further research and development.

  15. Direct Measurement and Chemical Speciation of Top Ring Zone Liquid During Engine Operation

    SciTech Connect (OSTI)

    Splitter, Derek A; Burrows, Barry Clay; Lewis Sr, Samuel Arthur

    2015-01-01

    The present manuscript consists of proof of concept experiments involving direct measurements and detailed chemical speciation from the top ring zone of a running engine. The work uses a naturally aspirated single cylinder utility engine that has been modified to allow direct liquid sample acquisition from behind the top ring. Samples were analyzed and spectated using gas chromatographic techniques. Results show that the liquid mixture in the top ring zone is neither neat lubricant nor fuel but a combination of the two with unique chemical properties. At the tested steady state no-load operating condition, the chemical species of the top ring zone liquid were found to be highly dependent on boiling point, where both low reactivity higher boiling point fuel species and lubricant are observed to be the dominant constituents. The results show that at least for the tested condition, approximately 25% of the top ring zone is comprised of gasoline fuel like molecules, which are dominated by high octane number aromatic species, while the remainder of the liquid is comprised of lubricant like species.

  16. Transition between vortex rings and MAP solutions for electrically charged magnetic solutions

    SciTech Connect (OSTI)

    Wong, Khai-Ming; Soltanian, Amin; Teh, Rosy

    2014-03-05

    We consider the bifurcation and transition of axially symmetric monopole-antimonopole pair (MAP) and vortex ring solutions in the presence of electric charge for the SU(2) Yang-Mills-Higgs field theory. Here we investigate the properties of MAP/vortex ring solutions with n = 3,? = 0.65, for different Higgs field strength ?. For ? < 4.93, there is only one fundamental branch of vortex ring solution, but at the critical value of ?{sub b} = 4.93, branching happens and 2 sets of new solutions appeared. The new branch with less energy is a full MAP solution while the branch with higher energy contains MAP at the beginning and separation between poles of MAP on the z-axis reduces gradually and at another critical value of ?{sub t} = 14.852, they merge together at z = 0. Beyond this point the solutions change to the vortex ring solutions and a transitions between MAP and vortex ring solutions happens at this branch.

  17. Effects of spiral arms on star formation in nuclear rings of barred-spiral galaxies

    SciTech Connect (OSTI)

    Seo, Woo-Young; Kim, Woong-Tae E-mail: wkim@astro.snu.ac.kr

    2014-09-01

    We use hydrodynamic simulations to study the effect of spiral arms on the star formation rate (SFR) in nuclear rings of barred-spiral galaxies. We find that spiral arms can be an efficient means of gas transport from the outskirts to the central parts, provided that the arms are rotating slower than the bar. While the ring star formation in models with no arms or corotating arms is active only during around the bar growth phase, arm-driven gas accretion both significantly enhances and prolongs the ring star formation in models with slow-rotating arms. The arm-enhanced SFR is larger by a factor of ?3-20 than in the no-arm model, with larger values corresponding to stronger and slower arms. Arm-induced mass inflows also make dust lanes stronger. Nuclear rings in slow-arm models are ?45% larger than in the no-arm counterparts. Star clusters that form in a nuclear ring exhibit an age gradient in the azimuthal direction only when the SFR is small, whereas no notable age gradient is found in the radial direction for models with arm-induced star formation.

  18. De-icing: recovery of diffraction intensities in the presence of ice rings

    SciTech Connect (OSTI)

    Chapman, Michael S.; Somasundaram, Thayumanasamy

    2010-06-01

    Correction for ice-rings in diffraction images is demonstrated as an alternative to exclusion of affected reflections. Completeness can be increased without significant loss of quality in the integrated data. Macromolecular structures are routinely determined at cryotemperatures using samples flash-cooled in the presence of cryoprotectants. However, sometimes the best diffraction is obtained under conditions where ice formation is not completely ablated, with the result that characteristic ice rings are superimposed on the macromolecular diffraction. In data processing, the reflections that are most affected by the ice rings are usually excluded. Here, an alternative approach of subtracting the ice diffraction is tested. High completeness can be retained with little adverse effect upon the quality of the integrated data. This offers an alternate strategy when high levels of cryoprotectant lead to loss of crystal quality.

  19. Direct space-charge effects on the ILC damping rings: Task ForceReport

    SciTech Connect (OSTI)

    Venturini, Marco; Oide, Katsunobu

    2006-02-28

    In 2005 a global effort was initiated to conduct studies for a baseline recommendation for the various components of the International Linear Collider (ILC). Work for the damping rings was subdivided in a number of tasks. This Report contains the contribution to this effort by the Authors as Coordinators of the Task Force on space charge. (A slightly reduced version of this document can also be found as part of the ''Configuration Studies and Recommendations for the ILC Damping Rings'', Edts. A. Wolski, et al., LBNL-59449.) The studies documented in this Report were carried out for several of the reference lattices considered for the baseline recommendation. Space charge effects were found to be quite noticeable in the lattices with the longest circumference. Although it does not appear that they could prevent operation of any machine having such lattices they do favor a choice of a ring design with shorter ({approx}6km) circumference at 5 GeV.

  20. Spin polarized current from multiply-coupled rings with Zeeman-split quantum dots

    SciTech Connect (OSTI)

    Hedin, Eric R.; Joe, Yong S.

    2014-03-21

    We investigate transmission resonances and conductance properties of multiple, serially connected, direct-contact nanoscale rings using the tight-binding model. Quantum dots (QDs) are embedded in the two arms of each ring, and Zeeman-splitting of the QD energy levels is incorporated into the system Hamiltonian. Transmission bands develop as the number of rings in series increases, with a band-gap which is sensitive to the degree of Zeeman splitting and the initial settings of the QD site energy values. The current vs. voltage characteristics of the system can be modulated between Ohmic and semiconducting as a function of the Zeeman splitting. In addition, spin-polarized current results for selected ranges of the Fermi energy.

  1. Homometallic and Heterometallic Antiferromagnetic Rings: Magnetic Properties Studied by Nuclear Magnetic Resonance

    SciTech Connect (OSTI)

    Casadei, Cecilia

    2012-05-09

    The aim of the present thesis is to investigate the local magnetic properties of homometallic Cr{sub 8} antiferromagnetic (AFM) ring and the changes occurring by replacing one Cr{sup 3+} ion with diamagnetic Cd{sup 2+} (Cr{sub 7}Cd) and with Ni{sup 2+} (Cr{sub 7}Ni). In the heterometallic ring a redistribution of the local magnetic moment is expected in the low temperature ground state. We have investigated those changes by both {sup 53}Cr-NMR and {sup 19}F-NMR. We have determined the order of magnitude of the transferred hyperfine coupling constant {sup 19}F - M{sup +} where M{sup +} = Cr{sup 3+}, Ni{sup 2+} in the different rings. This latter result gives useful information about the overlapping of the electronic wavefunctions involved in the coordinative bond.

  2. Conceptual MEIC electron ring injection scheme using CEBAF as a full energy injector

    SciTech Connect (OSTI)

    Guo, Jiquan; Lin, Fanglei; Rimmer, Robert A.; Wang, Haipeng; Wang, Shaoheng; Zhang, Yuhong

    2015-09-01

    The Medium-energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab is planning to use the newly upgraded 12 GeV CEBAF 1497 MHz SRF CW recirculating linac as a full-energy injector for the electron collider ring. The electron collider ring is proposed to reuse the 476MHz PEP-II RF system to achieve high installed voltage and high beam power. The MEIC electron injection requires 3-10 (or 12) GeV beam in 3-4µs long bunch trains with low duty factor and high peak current, resulting in strong transient beam loading for the CEBAF. In this paper, we propose an injection scheme that can match the two systems' frequencies with acceptable injection time, and also address the transient beam loading issue in CEBAF. The scheme is compatible with future upgrade to 952.6 MHz SRF system in the electron ring.

  3. Photocapacitance study of type-II GaSb/GaAs quantum ring solar cells

    SciTech Connect (OSTI)

    Wagener, M. C.; Botha, J. R.; Carrington, P. J.; Krier, A.

    2014-01-07

    In this study, the density of states associated with the localization of holes in GaSb/GaAs quantum rings are determined by the energy selective charging of the quantum ring distribution. The authors show, using conventional photocapacitance measurements, that the excess charge accumulated within the type-II nanostructures increases with increasing excitation energies for photon energies above 0.9?eV. Optical excitation between the localized hole states and the conduction band is therefore not limited to the ?(k?=?0) point, with pseudo-monochromatic light charging all states lying within the photon energy selected. The energy distribution of the quantum ring states could consequently be accurately related from the excitation dependence of the integrated photocapacitance. The resulting band of localized hole states is shown to be well described by a narrow distribution centered 407?meV above the GaAs valence band maximum.

  4. THREE-DIMENSIONAL DUST MAPPING REVEALS THAT ORION FORMS PART OF A LARGE RING OF DUST

    SciTech Connect (OSTI)

    Schlafly, E. F.; Rix, H.-W.; Martin, N. F.; Green, G.; Finkbeiner, D. P.; Burgett, W. S.; Chambers, K. C.; Kaiser, N.; Morgan, J. S.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.; Draper, P. W.; Metcalfe, N.; Price, P. A.

    2015-02-01

    The Orion Molecular Complex is the nearest site of ongoing high-mass star formation, making it one of the most extensively studied molecular complexes in the Galaxy. We have developed a new technique for mapping the three-dimensional distribution of dust in the Galaxy using Pan-STARRS1 photometry. We isolate the dust at the distance to Orion using this technique, revealing a large (100 pc, 14 diameter), previously unrecognized ring of dust, which we term the ''Orion dust ring''. The ring includes Orion A and B, and is not coincident with current H? features. The circular morphology suggests formation as an ancient bubble in the interstellar medium, though we have not been able to conclusively identify the source of the bubble. This hint at the history of Orion may have important consequences for models of high-mass star formation and triggered star formation.

  5. Planar LIF observation of unburned fuel escaping the upper ring-land crevice in an SI engine

    SciTech Connect (OSTI)

    Green, R.M.; Cloutman, L.D.

    1997-01-01

    PLIF has been used to observe the in-cylinder transport of unburned fuel that, while trapped in the ring-land and ring-groove crevices, survives combustion in the propagating flame. Away from the top-ring gap, we detect a wall-jet comprised of unburned charge exiting the top ring-land crevice opening. At the location of the top-ring gap, we observed unburned fuel lying in the cool boundary layer along the cylinder wall during the later stages of the expansion stroke. This layer is scraped into the roll-up vortex during the exhaust stroke. These data lead us to conclude that away from the end gap, unburned, high pressure charge, trapped between the two compression rings escapes as a wall jet after ring-reversal near the bottom center. Conversely, at the ring gap, when the cylinder pressure drops below the pressure between the compression rings, the trapped charge escapes through the gap and forms a thin layer on the cylinder wall.

  6. De-icing: recovery of diffraction intensities in the presence of ice rings

    SciTech Connect (OSTI)

    Chapman, Michael S.; Somasundaram, Thayumanasamy

    2010-11-03

    Macromolecular structures are routinely determined at cryotemperatures using samples flash-cooled in the presence of cryoprotectants. However, sometimes the best diffraction is obtained under conditions where ice formation is not completely ablated, with the result that characteristic ice rings are superimposed on the macromolecular diffraction. In data processing, the reflections that are most affected by the ice rings are usually excluded. Here, an alternative approach of subtracting the ice diffraction is tested. High completeness can be retained with little adverse effect upon the quality of the integrated data. This offers an alternate strategy when high levels of cryoprotectant lead to loss of crystal quality.

  7. Assembling a ring-shaped crystal in a microfabricated surface ion trap

    SciTech Connect (OSTI)

    Stick, Daniel Lynn; Tabakov, Boyan; Benito, Francisco; Blain, Matthew; Clark, Craig R.; Clark, Susan; Haltli, Raymond A.; Maunz, Peter; Sterk, Jonathan D.; Tigges, Chris

    2015-09-01

    We report on experiments with a microfabricated surface trap designed for confining a chain of ions in a ring. Uniform ion separation over most of the ring is achieved with a rotationally symmetric design and by measuring and suppressing undesired electric fields. After reducing stray fields, the ions are confined primarily by a radio-frequency pseudopotential and their mutual Coulomb repulsion. As a result, approximately 400 40Ca+ ions with an average separation of 9 μm comprise the ion crystal.

  8. Manganese oxide helices, rings, strands, and films, and methods for their preparation

    DOE Patents [OSTI]

    Suib, Steven L.; Giraldo, Oscar; Marquez, Manuel; Brock, Stephanie

    2003-01-07

    Methods for the preparation of mixed-valence manganese oxide compositions with quaternary ammonium ions are described. The compositions self-assemble into helices, rings, and strands without any imposed concentration gradient. These helices, rings, and strands, as well as films having the same composition, undergo rapid ion exchange to replace the quaternary ammonium ions with various metal ions. And the metal-ion-containing manganese oxide compositions so formed can be heat treated to form semi-conducting materials with high surface areas.

  9. Used Fuel Disposition Campaign Phase I Ring Compression Testing of High Burnup Cladding

    Office of Energy Efficiency and Renewable Energy (EERE)

    The purpose of ring compression testing is to generate data to support the development of the technical basis for extended storage and transportation of high-burnup fuel. This report highlights the results of completed Phase I testing of high-burnup M5® cladding and the revised three-year test plan. The goal of the ring compression testing is to identify process conditions that would minimize radial-hydride formation and the corresponding DBTT of high-burnup fuel cladding and to generate data and models to support the development of the technical basis for extended storage and transportation of high-burnup fuel.

  10. A Feasibility Study of an e e- Ring Collider for Higgs Factory (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect A Feasibility Study of an e e- Ring Collider for Higgs Factory Citation Details In-Document Search Title: A Feasibility Study of an e e- Ring Collider for Higgs Factory Authors: Cai, Yunhai ; Chao, Alex ; Nosochkov, Yuri ; Wienands, Uli ; Zimmermann, Frank ; /SLAC Publication Date: 2013-04-22 OSTI Identifier: 1074169 Report Number(s): SLAC-PUB-15416 DOE Contract Number: AC02-76SF00515 Resource Type: Journal Article Resource Relation: Journal Name: Submitted to

  11. High-pressure structure made of rings with peripheral weldments of reduced thickness

    DOE Patents [OSTI]

    Leventry, Samuel C.

    1988-01-01

    A high-pressure structure having a circular cylindrical metal shell made of metal rings joined together by weldments and which have peripheral areas of reduced shell thickness at the weldments which permit a reduction in the amount of weld metal deposited while still maintaining sufficient circumferential or hoop stress strength.

  12. Simulations of the Electron Cloud Builld Up and Instabilities for Various ILC Damping Ring Configurations

    SciTech Connect (OSTI)

    Pivi, Mauro; Raubenheimer, Tor O.; Wang, Lanfa; Ohmi, Kazuhito; Wanzenberg, Rainer; Wolski, Andrzej; /Liverpool U. /Cockcroft Inst. Accel. Sci. Tech.

    2007-03-12

    In the beam pipe of the positron damping ring of the International Linear Collider (ILC), an electron cloud may be first produced by photoelectrons and ionization of residual gases and then increased by the secondary emission process. This paper reports the assessment of electron cloud effects in a number of configuration options for the ILC baseline configuration. Careful estimates were made of the secondary electron yield (sometimes in the literature also referred as secondary emission yield SEY or {delta}, with a peak value {delta}{sub max}) threshold for electron cloud build-up, and the related single- and coupled-bunch instabilities, as a function of beam current and surface properties for a variety of optics designs. When the configuration for the ILC damping rings was chosen at the end of 2005, the results from these studies were important considerations. On the basis of the joint theoretical and experimental work, the baseline configuration currently specifies a pair of 6 km damping rings for the positron beam, to mitigate the effects of the electron cloud that could present difficulties in a single 6 km ring. However, since mitigation techniques are now estimated to be sufficiently mature, a reduced single 6-km circumference is presently under consideration so as to reduce costs.

  13. REVIEW OF AGING DATA ON EPDM O-RINGS IN THE H1616 SHIPPING PACKAGE

    SciTech Connect (OSTI)

    Skidmore, E.

    2012-03-27

    Currently, all H1616 shipping package containers undergo annual re-verification testing, including containment vessel leak testing to verify leak-tightness (<1 x 10{sup -7} ref cc/sec air) as per ANSI N14.5. The purpose of this literature review is to supplement aging studies currently being performed by SRNL on the EPDM O-rings to provide the technical basis for extending annual re-verification testing for the H1616 shipping package and to predict the life of the seals at bounding service conditions. The available data suggest that the EPDM O-rings can retain significant mechanical properties and sealing force at or below bounding service temperatures (169 F or 76 C) beyond the 1 year maintenance period. Interpretation of available data suggests that a service life of at least 2 years and potentially 4-6 years may be possible at bounding temperatures. Seal lifetimes at lower, more realistic temperatures will likely be longer. Being a hydrocarbon elastomer, EPDM O-rings may exhibit an inhibition period due to the presence of antioxidants. Once antioxidants are consumed, mechanical properties and seal performance could decline at a faster rate. Testing is being performed to validate the assumptions outlined in this report and to assess the long-term performance of O-ring seals under actual service conditions.

  14. Disordered organic electronic materials based on non-benzenoid 1,6-methano[10]annulene rings

    DOE Patents [OSTI]

    Tovar, John D; Streifel, Benjamin C; Peart, Patricia A

    2014-10-07

    Conjugated polymers and small molecules including the nonplanar aromatic 1,6-methano[10]annulene ring structure along with aromatic subunits, such as diketopyrrolopyrrole, and 2,1,3-benzothiadiazole, substituted with alkyl chains in a "Tail In," "Tail Out," or "No Tail" regiochemistry are disclosed.

  15. Fabrication and characterization of large arrays of mesoscopic gold rings on large-aspect-ratio cantilevers

    SciTech Connect (OSTI)

    Ngo, D. Q.; Petkovi?, I. Lollo, A.; Castellanos-Beltran, M. A.; Harris, J. G. E.

    2014-10-15

    We have fabricated large arrays of mesoscopic metal rings on ultrasensitive cantilevers. The arrays are defined by electron beam lithography and contain up to 10{sup 5} rings. The rings have a circumference of 1 ?m, and are made of ultrapure (6N) Au that is deposited onto a silicon-on-insulator wafer without an adhesion layer. Subsequent processing of the SOI wafer results in each array being supported at the end of a free-standing cantilever. To accommodate the large arrays while maintaining a low spring constant, the cantilevers are nearly 1 mm in both lateral dimensions and 100 nm thick. The extreme aspect ratio of the cantilevers, the large array size, and the absence of a sticking layer are intended to enable measurements of the rings' average persistent current in the presence of relatively small magnetic fields. We describe the motivation for these measurements, the fabrication of the devices, and the characterization of the cantilevers' mechanical properties. We also discuss the devices' expected performance in measurements of .

  16. Tenth interim status report: Model 9975 O-ring fixture long-term leak performance

    SciTech Connect (OSTI)

    Daugherty, W. L.

    2015-08-26

    A series of experiments to monitor the aging performance of Viton® GLT O-rings used in the Model 9975 package has been ongoing since 2004 at the Savannah River National Laboratory. One approach has been to periodically evaluate the leak performance of O-rings being aged in mock-up 9975 Primary Containment Vessels (PCVs) at elevated temperatures. Other methods such as compression-stress relaxation (CSR) tests and field surveillance are also on-going to evaluate O-ring behavior. Seventy tests using PCV mock-ups were assembled and heated to temperatures ranging from 200 to 450 °F. They were leak-tested initially and have been tested periodically to determine if they continue to meet the leak-tightness criterion defined in ANSI standard N14.5-97. Due to material substitution, fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 °F.

  17. Design of the Proposed Low Energy Ion Collider Ring at Jefferson Lab

    SciTech Connect (OSTI)

    Nissen, Edward W.; Lin, Fanglei; Morozov, Vasiliy; Zhang, Yuhong

    2013-06-01

    The polarized Medium energy Electron-Ion Collider (MEIC) envisioned at Jefferson Lab will cover a range of center-of-mass energies up to 65 GeV. The present MEIC design could also allow the accommodation of low energy electron-ion collisions (LEIC) for additional science reach. This paper presents the first design of the low energy ion collider ring which is converted from the large ion booster of MEIC. It can reach up to 25 GeV energy for protons and equivalent ion energies of the same magnetic rigidity. An interaction region and an electron cooler designed for MEIC are integrated into the low energy collider ring, in addition to other required new elements including crab cavities and ion spin rotators, for later reuse in MEIC itself. A pair of vertical chicanes which brings the low energy ion beams to the plane of the electron ring and back to the low energy ion ring are also part of the design.

  18. Mechanisms underlying the active self-assembly of microtubule rings and spools

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

    VanDelinder, Virginia; Brener, Stephanie; Bachand, George D.

    2016-02-04

    Here, active self-assembly offers a powerful route for the creation of dynamic multiscale structures that are presently inaccessible with standard microfabrication techniques. One such system uses the translation of microtubule filaments by surface-tethered kinesin to actively assemble nanocomposites with bundle, ring, and spool morphologies. Attempts to observe mechanisms involved in this active assembly system have been hampered by experimental difficulties with performing observation during buffer exchange and photodamage from fluorescent excitation. In the present work, we used a custom microfluidic device to remove these limitations and directly study ring/spool formation, including the earliest events (nucleation) that drive subsequent nanocomposite assembly.more » Three distinct formation events were observed: pinning, collisions, and induced curvature. Of these three, collisions accounted for the majority of event leading to ring/spool formation, while the rate of pinning was shown to be dependent on the amount of photodamage in the system. We further showed that formation mechanism directly affects the diameter and rotation direction of the resultant rings and spools. Overall, the fundamental understanding described in this work provides a foundation by which the properties of motor-driven, actively assembled nanocomposites may be tailored toward specific applications.« less

  19. Constriction model of actomyosin ring for cytokinesis by fission yeast using a two-state sliding filament mechanism

    SciTech Connect (OSTI)

    Jung, Yong-Woon; Mascagni, Michael

    2014-09-28

    We developed a model describing the structure and contractile mechanism of the actomyosin ring in fission yeast, Schizosaccharomyces pombe. The proposed ring includes actin, myosin, and α-actinin, and is organized into a structure similar to that of muscle sarcomeres. This structure justifies the use of the sliding-filament mechanism developed by Huxley and Hill, but it is probably less organized relative to that of muscle sarcomeres. Ring contraction tension was generated via the same fundamental mechanism used to generate muscle tension, but some physicochemical parameters were adjusted to be consistent with the proposed ring structure. Simulations allowed an estimate of ring constriction tension that reproduced the observed ring constriction velocity using a physiologically possible, self-consistent set of parameters. Proposed molecular-level properties responsible for the thousand-fold slower constriction velocity of the ring relative to that of muscle sarcomeres include fewer myosin molecules involved, a less organized contractile configuration, a low α-actinin concentration, and a high resistance membrane tension. Ring constriction velocity is demonstrated as an exponential function of time despite a near linear appearance. We proposed a hypothesis to explain why excess myosin heads inhibit constriction velocity rather than enhance it. The model revealed how myosin concentration and elastic resistance tension are balanced during cytokinesis in S. pombe.

  20. Higher-order paraxial theory of the propagation of ring rippled laser beam in plasma: Relativistic ponderomotive regime

    SciTech Connect (OSTI)

    Purohit, Gunjan Rawat, Priyanka; Chauhan, Prashant; Mahmoud, Saleh T.

    2015-05-15

    This article presents higher-order paraxial theory (non-paraxial theory) for the ring ripple formation on an intense Gaussian laser beam and its propagation in plasma, taking into account the relativistic-ponderomotive nonlinearity. The intensity dependent dielectric constant of the plasma has been determined for the main laser beam and ring ripple superimposed on the main laser beam. The dielectric constant of the plasma is modified due to the contribution of the electric field vector of ring ripple. Nonlinear differential equations have been formulated to examine the growth of ring ripple in plasma, self focusing of main laser beam, and ring rippled laser beam in plasma using higher-order paraxial theory. These equations have been solved numerically for different laser intensities and plasma frequencies. The well established experimental laser and plasma parameters are used in numerical calculation. It is observed that the focusing of the laser beams (main and ring rippled) becomes fast in the nonparaxial region by expanding the eikonal and other relevant quantities up to the fourth power of r. The splitted profile of laser beam in the plasma is observed due to uneven focusing/defocusing of the axial and off-axial rays. The growths of ring ripple increase when the laser beam intensity increases. Furthermore, the intensity profile of ring rippled laser beam gets modified due to the contribution of growth rate.

  1. PHYSICAL PROPERTIES OF THE CIRCUMNUCLEAR STARBURST RING IN THE BARRED GALAXY NGC 1097

    SciTech Connect (OSTI)

    Hsieh, Pei-Ying; Matsushita, Satoki; Ho, Paul T. P.; Wu, Ya-Lin; Liu, Guilin; Oi, Nagisa

    2011-08-01

    We report high-resolution {sup 12}CO(J = 2-1), {sup 13}CO(J = 2-1), and {sup 12}CO(J = 3-2) imaging of the Seyfert 1/starburst ring galaxy NGC 1097 with the Submillimeter Array for the purpose of studying the physical and kinematic properties of the 1 kpc circumnuclear starburst ring. Individual star clusters as detected in the Hubble Space Telescope map of Pa{alpha} line emission have been used to determine the star formation rate (SFR), and are compared with the properties of the molecular gas. The molecular ring has been resolved into individual clumps at the giant molecular cloud association (GMA) scale of 200-300 pc in all three CO lines. The intersection between the dust lanes and the starburst ring, which is associated with the orbit-crowding region, is resolved into two physically/kinematically distinct features in the 1.''5 x 1.''0 (105 x 70 pc) {sup 12}CO(J = 2-1) map. The clumps associated with the dust lanes have broader line widths, higher surface gas densities, and lower SFRs, while the narrow line clumps associated with the starburst ring have opposite characteristics. A Toomre-Q value lower than unity at the radius of the ring suggests that the molecular ring is gravitationally unstable to fragmentation at GMA scale. The line widths and surface density of the gas mass of the clumps show an azimuthal variation related to the large-scale dynamics. The SFR, on the other hand, is not significantly affected by the dynamics, but has a correlation with the intensity ratio of {sup 12}CO (J = 3-2) and {sup 12}CO(J = 2-1), which traces the denser gas associated with star formation. Our resolved CO map, especially in the orbit-crowding region, observationally demonstrates for the first time that the physical/kinematic properties of GMAs are affected by the large-scale bar-potential dynamics in NGC 1097.

  2. Aging Behavior of the EPDM O-Rings in the H1616 Shipping Package

    SciTech Connect (OSTI)

    Daugherty, W.; Stefek, T.; Skidmore, E.

    2015-06-09

    The H1616 shipping package is used within the DOE complex for shipping tritium reservoirs. The annual recertification frequency can create logistical difficulties with other constraints on the timing of shipments; thus, a longer re-certification period is desirable. The ethylene propylene diene monomer (EPDM) O-rings used in the H1616 shipping package are being aged and tested at the Savannah River National Laboratory (SRNL) to provide a technical basis for extending the annual maintenance of the H1616 shipping package. H1616 EPDM O-rings are being aged at elevated temperature, and tested for degradation in mechanical properties, compression stress relaxation (CSR) behavior, and leak performance. Mechanical properties of aged O-rings show significant degradation can occur, but an inert atmosphere (argon backfill) greatly reduces the rate of degradation. The CSR behavior of O-rings was evaluated in air at 79 to 177 °C. These collective data were used to develop a predictive model for extrapolation of CSR behavior to relevant service temperatures (<67 °C). O-rings were also aged in H1616 Containment Vessels (CV) in an inert atmosphere at 71 to 149 °C. The vessels are helium leak tested periodically to determine if they continue to remain leak-tight. The vessel tests provide a solid demonstration that the H1616 O-rings will remain leak-tight at temperatures up to 113 °C for up to approximately 2.3 years. Significantly longer periods of leak-tight service are expected at the lower temperatures actually experienced in service. The predictive model developed from the CSR data conservatively indicates a service life of ~5 years at 67 °C. Although the relationship between CSR behavior and leak-tight performance has not been established for this design, the CSR predictions for this O-ring are conservative relative to leak-tight performance. Based on the collective data developed to date, SRNL has recommended that the maintenance interval for the H1616 package be

  3. Management of wildlife causing damage at Argonne National Laboratory-East, DuPage County, Illinois

    SciTech Connect (OSTI)

    1995-04-01

    The DOE, after an independent review, has adopted an Environmental Assessment (EA) prepared by the US Department of Agriculture (USDA) which evaluates use of an Integrated Wildlife Damage Management approach at Argonne National Laboratory-East (ANL-E) in DuPage County, Illinois (April 1995). In 1994, the USDA issued a programmatic Environmental Impact Statement (EIS) that covers nationwide animal damage control activities. The EA for Management of Wildlife Causing Damage at ANL-E tiers off this programmatic EIS. The USDA wrote the EA as a result of DOE`s request to USDA to prepare and implement a comprehensive Wildlife Management Damage Plan; the USDA has authority for animal damage control under the Animal Damage Control Act of 1931, as amended, and the Rural Development, Agriculture and Related Agencies Appropriations Act of 1988. DOE has determined, based on the analysis in the EA, that the proposed action does not constitute a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act of 1969 (NEPA). Therefore, the preparation of an EIS is not required. This report contains the Environmental Assessment, as well as the Finding of No Significant Impact (FONSI).

  4. Morphological characterization of O-rings from the GCEP long-term test program. [Dupont 1141, 3M 4762 and 4768, and Parker V884-75 O-rings

    SciTech Connect (OSTI)

    Hughes, M.R.; Nolan, T.A.

    1984-07-30

    Based on the results of the morphological and structural characterizations reported herein the following conclusions have been reached. (1) O-rings of any of the four materials studied should last at least 10 years when employed in a standard static seal configuration utilizing a groove that holds the O-ring. (2) Such a static seal provides considerable protection from reaction. (3) The reaction of UF/sub 6/ with the O-ring material is the dominant degradation reaction; however there are effects on a least one compound that appear to be related to HF penetration into the O-ring matrix. The slow nature of the reaction of UF/sub 6/ with the flanged O-rings makes life projections quite difficult using any means. It would appear that one of the best methods for determining the life of these materials would be actual use combined with routine long-term inspection/sampling of a selected typical subset of O-rings. At GCEP conditions it would not be surprising to find the actual life of the O-rings is longer than any anticipated operation time of the plant facility. 16 figures, 1 table.

  5. Aging Behavior of the Viton® Fluoroelastomer O-Rings in the 9975 Shipping Package

    SciTech Connect (OSTI)

    Daugherty, W.; Mcwilliams, A.; Skidmore, E.

    2015-06-09

    The 9975 Type B shipping package is used within the DOE complex for shipping special nuclear materials. This package is re-certified annually in accordance with Safety Analysis Report requirements. The package is also used at the Savannah River Site as part of the long-term storage configuration of special nuclear materials. As such, the packages do not undergo annual recertification during storage, with uncertainty as to how long some of the package components will meet their functional requirements in the storage environment. The packages are currently approved for up to 15 years storage, and work continues to provide a technical basis to extend that period. This paper describes efforts by the Savannah River National Laboratory (SRNL) to extend the service life estimate of Viton® GLT and GLT-S fluoroelastomer O-rings used in the 9975 shipping package. O-rings of both compositions are undergoing accelerated aging at elevated temperature, and are periodically tested for compression stress relaxation (CSR) behavior and leak performance. The CSR behavior of O-rings was evaluated at temperatures from 79 °C to 177 °C. These collective data were used to develop predictive models for extrapolation of CSR behavior to relevant service temperatures (< 75 °C). O-rings were also aged in Primary Containment Vessel (PCV) fixtures at temperatures ranging from 79 °C to 232 °C. The fixtures are helium leak tested periodically to determine if they remain leak-tight. The PCV fixture tests demonstrate that the 9975 O-rings will remain leak-tight at temperatures up to 149 °C for 3 years or more, and no leak failures have been observed with up to 8 years aging at 93 °C. Significantly longer periods of leak-tight service are expected at the lower temperatures actually experienced in the storage environment. The predictive model developed from the CSR data conservatively indicates a service life of more than 20 years at the bounding temperature of 75 °C. Although the

  6. Transverse Beam Stability Measurement and Analysis for the SNS Accumulator Ring

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

    Xie, Zaipeng; Schulte, Mike; Hu, Yu Hen; Deibele, Craig E

    2015-01-01

    A Field-programmable gate array (FPGA) based transverse feedback damper system was implemented in the Spallation Neutron Source (SNS) accumulator ring with the intention to stabilize the electron-proton (e-p) instability in a frequency range from 1 MHz to 300 MHz. The transverse damper could also be used as a diagnostic tool by measuring the beam transfer function (BTF). An analysis of the BTF measurement provides the stability diagram for the production beam at SNS. This paper describes the feedback damper system and its set-up as the BTF diagnostic tool. Experimental BTF results are presented and beam stability analysis is performed basedmore » on the BTF measurements for the SNS accumulator ring.« less

  7. Collision dynamics of polyatomic molecules containing carbon rings at low temperatures

    SciTech Connect (OSTI)

    Li, Zhiying; Heller, Eric J.; Krems, Roman V.

    2014-09-14

    We explore the collision dynamics of complex hydrocarbon molecules (benzene, coronene, adamantane, and anthracene) containing carbon rings in a cold buffer gas of {sup 3}He. For benzene, we present a comparative analysis of the fully classical and fully quantum calculations of elastic and inelastic scattering cross sections at collision energies between 1 and 10 cm{sup ?1}. The quantum calculations are performed using the time-independent coupled channel approach and the coupled-states approximation. We show that the coupled-states approximation is accurate at collision energies between 1 and 20 cm{sup ?1}. For the classical dynamics calculations, we develop an approach exploiting the rigidity of the carbon rings and including low-energy vibrational modes without holonomic constraints. Our results illustrate the effect of the molecular shape and the vibrational degrees of freedom on the formation of long-lived resonance states that lead to low-temperature clustering.

  8. Reactive triblock polymers from tandem ring-opening polymerization for nanostructured vinyl thermosets

    SciTech Connect (OSTI)

    Amendt, Mark A.; Pitet, Louis M.; Moench, Sarah; Hillmyer, Marc A.

    2013-03-07

    Multiply functional hydroxyl telechelic poly(cyclooctene-s-5-norbornene-2-methylene methacrylate) was synthesized by ring opening metathesis (co)polymerization of cis-cyclooctene and 5-norbornene-2-methylene methacrylate using the second generation Grubbs catalyst in combination with a symmetric chain transfer agent bearing hydroxyl functionality. The resulting hydroxyl-telechelic polymer was used as a macroinitiator for the ring opening transesterification polymerization of d,l-lactide to form reactive poly(lactide)-b-poly(cyclooctene-s-5-norbornene-2-methylene methacrylate)-b-poly(lactide) triblock polymers. Subsequently, the triblocks were crosslinked by free radical copolymerization with several vinyl monomers including styrene, divinylbenzene, methyl methacrylate, and ethyleneglycol dimethacrylate. Certain conditions led to optically transparent thermosets with mesoscale phase separation as evidenced by small angle X-ray scattering, differential scanning calorimetry and transmission electron microscopy. Disordered, bicontinuous structures with nanoscopic domains were generated in several cases, rendering the samples attractive for size-selective membrane applications.

  9. Long-term evaluation of fluoroelastomer O-rings in UF/sub 6/

    SciTech Connect (OSTI)

    Russell, R.G.; Otey, M.G.; Dippo, G.L.

    1986-05-01

    A major component in the gaseous centrifuge enrichment plant (GCEP) was fluoroelastomer O-rings, which were used to seal the uranium hexafluoride (UF/sub 6/) gas system. A program utilizing accelerated test conditions was used to help identify the best material out of four selected candidates and to predict the service life of these materials at GCEP conditions. The tests included accelerated temperatures, mechanical stress, and UF/sub 6/ exposure. Data were evaluated using the Newman--Keuls/sup 1/ ranking system to identify the best material and a zero-order reaction rate equation to help predict service life. This presentation includes a description of the test facility, the materials tested, the types of tests, objectives of the study, service life predictions, and conclusions. The O-rings are predicted to last approx. 30 years, and a high-molecular-weight polymer had the best performance ranking.

  10. PERFORMANCE TESTING OF SPRING ENERGIZED C-RINGS FOR USE IN RADIOACTIVE MATERIAL PACKAGINGS CONTAINING TRITIUM

    SciTech Connect (OSTI)

    Blanton, P; Kurt Eberl, K

    2007-10-23

    This paper describes the sealing performance testing and results of silver-plated inconel Spring Energized C-Rings used for tritium containment in radioactive shipping packagings. The test methodology used follows requirements of the American Society of Mechanical Engineers (ASME) summarized in ASME Pressure Vessel Code (B&PVC), Section V, Article 10, Appendix IX (Helium Mass Spectrometer Test - Hood Technique) and recommendations by the American National Standards Institute (ANSI) described in ANSI N14.5-1997. The tests parameters bound the predicted structural and thermal responses from conditions defined in the Code of Federal Regulations 10 CFR 71. The testing includes an evaluation of the effects of pressure, temperature, flange deflection, surface roughness, permeation, closure torque, torque sequencing and re-use on performance of metal C-Ring seals.

  11. Simulation of radiation damping in rings, using stepwise ray-tracing methods

    SciTech Connect (OSTI)

    Meot, F.

    2015-06-26

    The ray-tracing code Zgoubi computes particle trajectories in arbitrary magnetic and/or electric field maps or analytical field models. It includes a built-in fitting procedure, spin tracking many Monte Carlo processes. The accuracy of the integration method makes it an efficient tool for multi-turn tracking in periodic machines. Energy loss by synchrotron radiation, based on Monte Carlo techniques, had been introduced in Zgoubi in the early 2000s for studies regarding the linear collider beam delivery system. However, only recently has this Monte Carlo tool been used for systematic beam dynamics and spin diffusion studies in rings, including eRHIC electron-ion collider project at the Brookhaven National Laboratory. Some beam dynamics aspects of this recent use of Zgoubi capabilities, including considerations of accuracy as well as further benchmarking in the presence of synchrotron radiation in rings, are reported here.

  12. On the momentum of solitons and vortex rings in a superfluid

    SciTech Connect (OSTI)

    Pitaevskii, L. P.

    2014-12-15

    This paper is devoted to the calculation of the momentum of localized excitations, such as solitons and vortex rings, moving in a superfluid. The direct calculation of the momentum by integration of the mass flux density results in a badly-converging integral. I suggest a method for the renormalization of the integral with the explicit separation of a term related to the vortex line. This term can be calculated explicitly and gives the main contribution for the rings whose size is large compared to the healing length. I compare my method with the Jones and Roberts prescription for renormalization. I investigate the case of a uniform superfluid, and that of a superfluid in a cylindrical trap. I discuss the calculation of the jump in the phase of the order parameter and obtain a simple estimate for this jump.

  13. Self-generation of dissipative solitons in magnonic quasicrystal active ring resonator

    SciTech Connect (OSTI)

    Grishin, S. V. Beginin, E. N.; Morozova, M. A.; Sharaevskii, Yu. P.; Nikitov, S. A.

    2014-02-07

    Self-generation of dissipative solitons in the magnonic quasicrystal (MQC) active ring resonator is studied theoretically and experimentally. The developed magnonic crystal has quasiperiodic Fibonacci type structure. Frequency selectivity of the MQC together with the parametric three-wave decay of magnetostatic surface spin wave (MSSW) leads to the dissipative soliton self-generation. The transfer matrix method is used to describe MQC transmission responses. Besides, the model of MQC active ring resonator is suggested. The model includes three coupled differential equations describing the parametric decay of MSSW and two differential equations of linear oscillators describing the frequency selectivity of MQC. Numerical simulation results of dissipative soliton self-generation are in a fair agreement with experimental data.

  14. Condenser for ring-field deep-ultraviolet and extreme-ultraviolet lithography

    DOE Patents [OSTI]

    Chapman, Henry N.; Nugent, Keith A.

    2001-01-01

    A condenser for use with a ring-field deep ultraviolet or extreme ultraviolet lithography system. A condenser includes a ripple-plate mirror which is illuminated by a collimated beam at grazing incidence. The ripple plate comprises a plate mirror into which is formed a series of channels along an axis of the mirror to produce a series of concave surfaces in an undulating pattern. Light incident along the channels of the mirror is reflected onto a series of cones. The distribution of slopes on the ripple plate leads to a distribution of angles of reflection of the incident beam. This distribution has the form of an arc, with the extremes of the arc given by the greatest slope in the ripple plate. An imaging mirror focuses this distribution to a ring-field arc at the mask plane.

  15. Condenser for ring-field deep ultraviolet and extreme ultraviolet lithography

    DOE Patents [OSTI]

    Chapman, Henry N.; Nugent, Keith A.

    2002-01-01

    A condenser for use with a ring-field deep ultraviolet or extreme ultraviolet lithography system. A condenser includes a ripple-plate mirror which is illuminated by a collimated or converging beam at grazing incidence. The ripple plate comprises a flat or curved plate mirror into which is formed a series of channels along an axis of the mirror to produce a series of concave surfaces in an undulating pattern. Light incident along the channels of the mirror is reflected onto a series of cones. The distribution of slopes on the ripple plate leads to a distribution of angles of reflection of the incident beam. This distribution has the form of an arc, with the extremes of the arc given by the greatest slope in the ripple plate. An imaging mirror focuses this distribution to a ring-field arc at the mask plane.

  16. Simulation of radiation damping in rings, using stepwise ray-tracing methods

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

    Meot, F.

    2015-06-26

    The ray-tracing code Zgoubi computes particle trajectories in arbitrary magnetic and/or electric field maps or analytical field models. It includes a built-in fitting procedure, spin tracking many Monte Carlo processes. The accuracy of the integration method makes it an efficient tool for multi-turn tracking in periodic machines. Energy loss by synchrotron radiation, based on Monte Carlo techniques, had been introduced in Zgoubi in the early 2000s for studies regarding the linear collider beam delivery system. However, only recently has this Monte Carlo tool been used for systematic beam dynamics and spin diffusion studies in rings, including eRHIC electron-ion collider projectmore » at the Brookhaven National Laboratory. Some beam dynamics aspects of this recent use of Zgoubi capabilities, including considerations of accuracy as well as further benchmarking in the presence of synchrotron radiation in rings, are reported here.« less

  17. STAR CLUSTERS IN A NUCLEAR STAR FORMING RING: THE DISAPPEARING STRING OF PEARLS

    SciTech Connect (OSTI)

    Visnen, Petri; Barway, Sudhanshu; Randriamanakoto, Zara

    2014-12-20

    An analysis of the star cluster population in a low-luminosity early-type galaxy, NGC2328, is presented. The clusters are found in a tight star forming nuclear spiral/ring pattern and we also identify a bar from structural two-dimensional decomposition. These massive clusters are forming very efficiently in the circumnuclear environment and they are young, possibly all less than 30 Myr of age. The clusters indicate an azimuthal age gradient, consistent with a ''pearls-on-a-string'' formation scenario, suggesting bar-driven gas inflow. The cluster mass function has a robust down turn at low masses at all age bins. Assuming clusters are born with a power-law distribution, this indicates extremely rapid disruption at timescales of just several million years. If found to be typical, it means that clusters born in dense circumnuclear rings do not survive to become old globular clusters in non-interacting systems.

  18. Landau damping effects and evolutions of energy spread in small isochronous ring

    SciTech Connect (OSTI)

    Li, Yingjie; Wang, Langfa; Lin, Fanglei

    2014-11-01

    This paper presents the Landau damping effects on the microwave instability of a coasting long bunch in an isochronous ring due to finite energy spread and emittance. Our two-dimensional (2D) dispersion relation gives more accurate predictions of the microwave instability growth rates of short-wavelength perturbations than the conventional 1D formula. The long-term evolution of energy spread is also studied by measurements and simulations.

  19. Observation of the tune dependence of the stability threshold current in the PSR (Proton Storage Ring)

    SciTech Connect (OSTI)

    Wang, Tai Sen F.; Colton, E.; Lombardi, A.; Neuffer, D.V.; Thiessen, H.A.

    1989-01-01

    In the high-intensity unbunched-beam experiments carried out in the Proton Storage Ring at Los Alamos National Laboratory, the threshold current of vertical transverse instability showed pronounced differences when the betatron tune varied across an integer. In this paper, we shall present our experimental observations and discuss the possible relations between the threshold current and the machine impedance. The possible effects related to the distorted closed orbit are also discussed. 5 refs., 3 figs., 1 tab.

  20. Determination of nonuniform residual stress using the ring-core method

    SciTech Connect (OSTI)

    Ajovalasit, A.; Petrucci, G.; Zuccarello, B.

    1996-04-01

    This paper considers residual stress analysis using the ring-core method. In particular, the so-called integral equation method is applied to evaluate nonuniform residual stress fields. The proposed method overcomes typical drawbacks of the incremental strain method which lead to incorrect results for strongly varying stress fields. The experimental results obtained with a specimen subjected to a bending load confirm the theoretical predictions.

  1. Multielemental analysis of tree rings: temporal accumulation patterns and relationships with air pollution

    SciTech Connect (OSTI)

    Baes, C.F. III; McLaughlin, S.B.

    1983-01-01

    Short-leaf pine (Pinus echinata) tree rings collected in East Tennessee showed steadily increasing concentrations of Al, Cd, Cu, Fe, Mn, Mo, Ti, and Zn over the past 20 to 25 years. In part, these increasing concentrations result from recent declines in tree growth rate, but when corrected for variations in growth rate, annual accumulations of many of these metals in xylem tissue has increased in recent years. The largest concentration increases with time were observed in rings from trees downwind of the 1200 MW(e) generating Kingston steam plant, which burns 4 x 10/sup 9/ kg coal per year. Trace metals concentrations in cambial tissues were found to be as high as ten times those in the most recently formed xylem, and concentrations of Al, Cd, Mn, and Zn are near levels that have been associated with toxic effects when found in above-ground tissues of herbaceous plants. In trees sampled in the Great Smoky Mountains National Park (GSMNP) there was a period of suppressed growth and increased iron concentration in rings formed between 1863 and 1912. During this time period 88 km upwind, smelting of iron and copper sulfide ores was occurring at the Copper Basin (Copperhill), near Ducktown, Tennessee. Associated with this smelting were large uncontrolled releases of SO/sub 2/ which killed all vegetation within 20 km of the Copper Basin. The patterns of growth suppression and iron accumulation observed in the GSMNP trees correspond remarkably well to the initiation of smelting operations in 1854, maximum uncontrolled SO/sub 2/ emissions in 1895, and the reduction in SO/sub 2/ emissions mandated by the US Supreme Court in 1908. This historical pattern and the widespread occurrence of similar patterns of growth suppression and increased iron concentrations in tree rings since the late 1950s provide strong inferential evidence of tree response to SO/sub 2/ deposition. 36 references, 3 figures, 1 table.

  2. A modified post damping ring bunch compressor beamline for the TESLA linear collider

    SciTech Connect (OSTI)

    Philippe R.-G. Piot; Winfried Decking

    2004-03-23

    We propose a modified bunch compressor beamline, downstream of the damping ring, for the TESLA linear collider. This modified beamline uses a third harmonic radio-frequency section based on the 3.9 GHz superconducting cavity under development at Fermilab. In our design the beam deceleration is about {approx}50 MeV instead of {approx}450 MeV in the original design proposed.

  3. 20 keV undulators for a 6-GeV storage ring

    SciTech Connect (OSTI)

    Kim, S.H.; Cho, Y.

    1985-01-01

    The main goal of the future 6-GeV electron storage ring is to provide 20-keV fundamental harmonic radiations from insertion devices. Parameter restrictions of REC-vanadium permendur hybrid undulators have been examined. The critical factor is the achievable minimum gap of the undulator. Variations of the spectral brilliance for different beam parameters are also shown. 6 refs., 5 figs.

  4. The PEP-II Project: Low-Energy Ring Design and Project Status

    SciTech Connect (OSTI)

    Zisman, Michael S.

    2006-01-02

    We describe the present status of the PEP-II project. The project comprises four major systems: Injector, High-Energy Ring (HER), Low-Energy Ring (LER), and Interaction Region (IR). We focus in detail on the design of the LER, as its parameters and requirements are most closely related to those required for the Beijing Tau-Charm Factory rings. The PEP-II LER is a high-current, 3.1-GeV positron ring mounted above the 9-GeV HER. The LER uses a wiggler located in one of its six straight sections to provide emittance control and additional damping. We describe the rather complicated IR, which must transport the LER beam into the plane of the HER, focus it to a common beam size, and separate the beams after the head-on collisions. Both permanent magnet and conventional electromagnets are used in this area. The LER lattice has now adopted a simplified non-interleaved sextupole correction scheme that has reduced the required number of sextupoles substantially. We describe the LER vacuum system, one of the most challenging subsystems in PEP-II. It employs several technologies. In the arcs, aluminum extrusions and titanium sublimation pumps are employed; the straight sections use stainless steel chambers with lumped ion pumps. In the wiggler area, an extended copper photon dump with nonevaporable getter (NEG) pumps is employed to handle the very large synchrotron radiation power. The design of the room-temperature RF system, the bunch-by-bunch longitudinal and transverse feedback systems, and some of the special diagnostics will be described briefly. The PEP-II project remains on schedule to begin commissioning of the HER in April 1997, followed by the LER a year later.

  5. Cascade Problems in Some Atomic Lifetime Measurements at a Heavy-Ion Storage Ring

    SciTech Connect (OSTI)

    Trabert, E; Hoffmann, J; Krantz, C; Wolf, A; Ishikawa, Y; Santana, J

    2008-10-09

    Lifetimes of 3s{sup 2}3p{sup k} ground configuration levels of Al-, Si-, P-, and S-like ions of Be, Co, and Ni have been measured at a heavy-ion storage ring. Some of the observed decay curves show strong evidence of cascade repopulation from specific 3d levels that feature lifetimes in the same multi-millisecond range as the levels of the ground configuration.

  6. Radiation effects in a muon collider ring and dipole magnet protection

    SciTech Connect (OSTI)

    Mokhov, N.V.; Kashikhin, V.V.; Novitski, I.; Zlobin, A.V.; /Fermilab

    2011-03-01

    The requirements and operating conditions for a Muon Collider Storage Ring (MCSR) pose significant challenges to superconducting magnets. The dipole magnets should provide a high magnetic field to reduce the ring circumference and thus maximize the number of muon collisions during their lifetime. One third of the beam energy is continuously deposited along the lattice by the decay electrons at the rate of 0.5 kW/m for a 1.5-TeV c.o.m. and a luminosity of 10{sup 34} cm{sup -2}s{sup -1}. Unlike dipoles in proton machines, the MCSR dipoles should allow this dynamic heat load to escape the magnet helium volume in the horizontal plane, predominantly towards the ring center. This paper presents the analysis and comparison of radiation effects in MCSR based on two dipole magnets designs. Tungsten masks in the interconnect regions are used in both cases to mitigate the unprecedented dynamic heat deposition and radiation in the magnet coils.

  7. Properties of the electron cloud in a high-energy positron and electron storage ring

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

    Harkay, K. C.; Rosenberg, R. A.

    2003-03-20

    Low-energy, background electrons are ubiquitous in high-energy particle accelerators. Under certain conditions, interactions between this electron cloud and the high-energy beam can give rise to numerous effects that can seriously degrade the accelerator performance. These effects range from vacuum degradation to collective beam instabilities and emittance blowup. Although electron-cloud effects were first observed two decades ago in a few proton storage rings, they have in recent years been widely observed and intensely studied in positron and proton rings. Electron-cloud diagnostics developed at the Advanced Photon Source enabled for the first time detailed, direct characterization of the electron-cloud properties in amore » positron and electron storage ring. From in situ measurements of the electron flux and energy distribution at the vacuum chamber wall, electron-cloud production mechanisms and details of the beam-cloud interaction can be inferred. A significant longitudinal variation of the electron cloud is also observed, due primarily to geometrical details of the vacuum chamber. Furthermore, such experimental data can be used to provide realistic limits on key input parameters in modeling efforts, leading ultimately to greater confidence in predicting electron-cloud effects in future accelerators.« less

  8. CIT-7, a crystalline, molecular sieve with pores bounded by 8 and 10-membered rings

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

    Schmidt, Joel E.; Xie, Dan; Rea, Thomas; Davis, Mark E.

    2015-01-23

    A new crystalline molecular sieve, denoted CIT-7, is synthesized using an imidazolium-based diquaternary organic structure directing agent (OSDA). The framework structure is determined from a combination of rotation electron diffraction and synchrotron X-ray powder diffraction data. The structure has 10 crystallographically unique tetrahedral atoms (T-atoms) in the unit cell, and can be described as an ordered arrangement of the [425462] mtw building unit and a previously unreported [4452] building unit. The framework contains a 2-dimensional pore system that is bounded by 10 T-atom rings (10-ring, 5.1 Å × 6.2 Å opening) that are connected with oval 8-rings (2.9 Å ×more » 5.5 Å opening) through medium-sized cavities (~7.9 Å) at the channel intersections. CIT-7 can be synthesized over a broad range of compositions including pure-silica and heteroatom, e.g., aluminosilicate and titanosilicate, containing variants.« less

  9. High temperature spin dynamics in linear magnetic chains, molecular rings, and segments by nuclear magnetic resonance

    SciTech Connect (OSTI)

    Adelnia, Fatemeh; Lascialfari, Alessandro; Mariani, Manuel; Ammannato, Luca; Caneschi, Andrea; Rovai, Donella; Winpenny, Richard; Timco, Grigore; Corti, Maurizio Borsa, Ferdinando

    2015-05-07

    We present the room temperature proton nuclear magnetic resonance (NMR) nuclear spin-lattice relaxation rate (NSLR) results in two 1D spin chains: the Heisenberg antiferromagnetic (AFM) Eu(hfac){sub 3}NITEt and the magnetically frustrated Gd(hfac){sub 3}NITEt. The NSLR as a function of external magnetic field can be interpreted very well in terms of high temperature spin dynamics dominated by a long time persistence of the decay of the two-spin correlation function due to the conservation of the total spin value for isotropic Heisenberg chains. The high temperature spin dynamics are also investigated in Heisenberg AFM molecular rings. In both Cr{sub 8} closed ring and in Cr{sub 7}Cd and Cr{sub 8}Zn open rings, i.e., model systems for a finite spin segment, an enhancement of the low frequency spectral density is found consistent with spin diffusion but the high cut-off frequency due to intermolecular anisotropic interactions prevents a detailed analysis of the spin diffusion regime.

  10. Crystal structure of a two-subunit TrkA octameric gating ring assembly

    SciTech Connect (OSTI)

    Deller, Marc C.; Johnson, Hope A.; Miller, Mitchell D.; Spraggon, Glen; Elsliger, Marc -André; Wilson, Ian A.; Lesley, Scott A.; Ye, Sheng

    2015-03-31

    The TM1088 locus of T. maritima codes for two proteins designated TM1088A and TM1088B, which combine to form the cytosolic portion of a putative Trk K⁺ transporter. We report the crystal structure of this assembly to a resolution of 3.45 Å. The high resolution crystal structures of the components of the assembly, TM1088A and TM1088B, were also determined independently to 1.50 Å and 1.55 Å, respectively. The TM1088 proteins are structurally homologous to each other and to other K⁺ transporter proteins, such as TrkA. These proteins form a cytosolic gating ring assembly that controls the flow of K⁺ ions across the membrane. TM1088 represents the first structure of a two-subunit Trk assembly. Despite the atypical genetics and chain organization of the TM1088 assembly, it shares significant structural homology and an overall quaternary organization with other single-subunit K⁺ gating ring assemblies. This structure provides the first structural insights into what may be an evolutionary ancestor of more modern single-subunit K⁺ gating ring assemblies.

  11. Localized states in a semiconductor quantum ring with a tangent wire

    SciTech Connect (OSTI)

    Yang, F.; Wu, M. W.

    2014-08-28

    We extend a special kind of localized state trapped at the intersection due to the geometric confinement, first proposed in a three-terminal-opening T-shaped structure [L. A. Openov, Europhys. Lett. 55, 539 (2001)], into a ring geometry with a tangent connection to the wire. In this ring geometry, there exists one localized state trapped at the intersection with energy lying inside the lowest subband. We systematically study this localized state and the resulting Fano-type interference due to the coupling between this localized state and the continuum ones. It is found that the increase of inner radius of the ring weakens the coupling to the continuum ones and the asymmetric Fano dip fades away. A wide energy gap in transmission appears due to the interplay of two types of antiresonances: the Fano-type antiresonance and the structure antiresonance. The size of this antiresonance gap can be modulated by adjusting the magnetic flux. Moreover, a large transmission amplitude can be obtained in the same gap area. The strong robustness of the antiresonance gap is demonstrated and shows the feasibility of the proposed geometry for a real application.

  12. The RCK Domain of the KtrAB K+ Transporter: Multiple Conformations of an Octameric Ring

    SciTech Connect (OSTI)

    Albright,R.; Vazquez Ibar, J.; Kim, C.; Gruner, S.; Morais-Cabral, J.

    2006-01-01

    The KtrAB ion transporter is a complex of the KtrB membrane protein and KtrA, an RCK domain. RCK domains regulate eukaryotic and prokaryotic membrane proteins involved in K{sup +} transport. Conflicting functional models have proposed two different oligomeric arrangements for RCK domains, tetramer versus octamer. Our results for the KtrAB RCK domain clearly show an octamer in solution and in the crystal. We determined the structure of this protein in three different octameric ring conformations that resemble the RCK-domain octamer observed in the MthK potassium channel but show striking differences in size and symmetry. We present experimental evidence for the association between one RCK octameric ring and two KtrB membrane proteins. These results provide insights into the quaternary organization of the KtrAB transporter and its mechanism of activation and show that the RCK-domain octameric ring model is generally applicable to other ion-transport systems.

  13. Platelets to rings: Influence of sodium dodecyl sulfate on Zn-Al layered double hydroxide morphology

    SciTech Connect (OSTI)

    Yilmaz, Ceren; Unal, Ugur; Yagci Acar, Havva

    2012-03-15

    In the current study, influence of sodium dodecyl sulfate (SDS) on the crystallization of Zn-Al layered double hydroxide (LDH) was investigated. Depending on the SDS concentration coral-like and for the first time ring-like morphologies were obtained in a urea-hydrolysis method. It was revealed that the surfactant level in the starting solution plays an important role in the morphology. Concentration of surfactant equal to or above the anion exchange capacity of the LDH is influential in creating different morphologies. Another important parameter was the critical micelle concentration (CMC) of the surfactant. Surfactant concentrations well above CMC value resulted in ring-like structures. The crystallization mechanism was discussed. - Graphical abstract: Dependence of ZnAl LDH Morphology on SDS concentration. Highlights: Black-Right-Pointing-Pointer In-situ intercalation of SDS in ZnAl LDH was achieved via urea hydrolysis method. Black-Right-Pointing-Pointer Morphology of ZnAl LDH intercalated with SDS depended on the SDS concentration. Black-Right-Pointing-Pointer Ring like morphology for SDS intercalated ZnAl LDH was obtained for the first time. Black-Right-Pointing-Pointer Growth mechanism was discussed. Black-Right-Pointing-Pointer Template assisted growth of ZnAl LDH was proposed.

  14. CIT-7, a crystalline, molecular sieve with pores bounded by 8 and 10-membered rings

    SciTech Connect (OSTI)

    Schmidt, Joel E.; Xie, Dan; Rea, Thomas; Davis, Mark E.

    2015-01-23

    A new crystalline molecular sieve, denoted CIT-7, is synthesized using an imidazolium-based diquaternary organic structure directing agent (OSDA). The framework structure is determined from a combination of rotation electron diffraction and synchrotron X-ray powder diffraction data. The structure has 10 crystallographically unique tetrahedral atoms (T-atoms) in the unit cell, and can be described as an ordered arrangement of the [425462] mtw building unit and a previously unreported [4452] building unit. The framework contains a 2-dimensional pore system that is bounded by 10 T-atom rings (10-ring, 5.1 Å × 6.2 Å opening) that are connected with oval 8-rings (2.9 Å × 5.5 Å opening) through medium-sized cavities (~7.9 Å) at the channel intersections. CIT-7 can be synthesized over a broad range of compositions including pure-silica and heteroatom, e.g., aluminosilicate and titanosilicate, containing variants.

  15. Crystal structure of a two-subunit TrkA octameric gating ring assembly

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

    Deller, Marc C.; Johnson, Hope A.; Miller, Mitchell D.; Spraggon, Glen; Elsliger, Marc -André; Wilson, Ian A.; Lesley, Scott A.; Ye, Sheng

    2015-03-31

    The TM1088 locus of T. maritima codes for two proteins designated TM1088A and TM1088B, which combine to form the cytosolic portion of a putative Trk K⁺ transporter. We report the crystal structure of this assembly to a resolution of 3.45 Å. The high resolution crystal structures of the components of the assembly, TM1088A and TM1088B, were also determined independently to 1.50 Å and 1.55 Å, respectively. The TM1088 proteins are structurally homologous to each other and to other K⁺ transporter proteins, such as TrkA. These proteins form a cytosolic gating ring assembly that controls the flow of K⁺ ions acrossmore » the membrane. TM1088 represents the first structure of a two-subunit Trk assembly. Despite the atypical genetics and chain organization of the TM1088 assembly, it shares significant structural homology and an overall quaternary organization with other single-subunit K⁺ gating ring assemblies. This structure provides the first structural insights into what may be an evolutionary ancestor of more modern single-subunit K⁺ gating ring assemblies.« less

  16. On the stability of pick-up ion ring distributions in the outer heliosheath

    SciTech Connect (OSTI)

    Summerlin, Errol J.; Vias, Adolfo F.; Moore, Thomas E.; Christian, Eric R.; Cooper, John F., E-mail: errol.summerlin@nasa.gov, E-mail: adolfo.figueroa-vinas-1@nasa.gov, E-mail: thomas.e.moore@nasa.gov, E-mail: eric.r.christian@nasa.gov, E-mail: john.f.cooper@nasa.gov [Heliophysics Science Division, NASAs Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD (United States)

    2014-10-01

    The 'secondary energetic neutral atom (ENA)' hypothesis for the ribbon feature observed by the Interstellar Boundary Explorer (IBEX) posits that the neutral component of the solar wind continues beyond the heliopause and charge exchanges with interstellar ions in the Outer Heliosheath (OHS). This creates pick-up ions that gyrate about the draped interstellar magnetic field (ISMF) lines at pitch angles near 90 on the locus where the ISMF lies tangential to the heliopause and perpendicular to the heliocentric radial direction. This location closely coincides with the location of the ribbon feature according to the prevailing inferences of the ISMF orientation and draping. The locally gyrating ions undergo additional charge exchange and escape as free-flying neutral atoms, many of which travel back toward the inner solar system and are imaged by IBEX as a ribbon tracing out the locus described above. For this mechanism to succeed, the pick-up ions must diffuse in pitch angle slowly enough to permit secondary charge exchange before their pitch angle distribution substantially broadens away from 90. Previous work using linear Vlasov dispersion analysis of parallel propagating waves has suggested that the ring distribution in the OHS is highly unstable, which, if true, would make the secondary ENA hypothesis incapable of rendering the observed ribbon. In this paper, we extend this earlier work to more realistic ring distribution functions. We find that, at the low densities necessary to produce the observed IBEX ribbon via the secondary ENA hypothesis, growth rates are highly sensitive to the temperature of the beam and that even very modest temperatures of the ring beam corresponding to beam widths of <1 are sufficient to damp the self-generated waves associated with the ring beam. Thus, at least from the perspective of linear Vlasov dispersion analysis of parallel propagating waves, there is no reason to expect that the ring distributions necessary to produce the

  17. ASE/CAGI Meeting about Compressors and Compressed Air System...

    Energy Savers [EERE]

    ASECAGI Meeting about Compressors and Compressed Air System Efficiency On April 25, 2013, several representatives of energy ... Natural Gas Transmission, Storage and Distribution System ...

  18. ASES Solar 2003 Americas Secure Energy

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

    Florida Solar Energy CenterUniversity of Central Florida 1679 Clearlake Road, Cocoa, Florida 32922, USA (321) 638-1000 All rights reserved. Disclaimer The Florida Solar Energy ...

  19. Controlling the magnetic susceptibility in an artificial elliptical quantum ring by magnetic flux and external Rashba effect

    SciTech Connect (OSTI)

    Omidi, Mahboubeh Faizabadi, Edris

    2015-03-21

    Magnetic susceptibility is investigated in a man-made elliptical quantum ring in the presence of Rashba spin-orbit interactions and the magnetic flux. It is shown that magnetic susceptibility as a function of magnetic flux changes between negative and positive signs periodically. The periodicity of the Aharonov-Bohm oscillations depends on the geometry of the region where magnetic field is applied, the eccentricity, and number of sites in each chain ring (the elliptical ring is composed of chain rings). The magnetic susceptibility sign can be reversed by tuning the Rashba spin-orbit strength as well. Both the magnetic susceptibility strength and sign can be controlled via external spin-orbit interactions, which can be exploited in spintronics and nanoelectronics.

  20. Structure of an E3:E2~Ub Complex Reveals an Allosteric Mechanism Shared among RING/U-box Ligases

    SciTech Connect (OSTI)

    Pruneda, Jonathan N.; Littlefield, Peter J.; Soss, Sarah E.; Nordquist, Kyle A.; Chazin, Walter J.; Brzovic, Peter S.; Klevit, Rachel E.

    2012-09-28

    Despite the widespread importance of RING/U-box E3 ubiquitin ligases in ubiquitin (Ub) signaling, the mechanismby which this class of enzymes facilitates Ub transfer remains enigmatic. Here, we present a structural model for a RING/U-box E3:E2~Ub complex poised for Ub transfer. The model and additional analyses reveal that E3 binding biases dynamic E2~Ub ensembles toward closed conformations with enhanced reactivity for substrate lysines. We identify a key hydrogen bond between a highly conserved E3 side chain and an E2 backbone carbonyl, observed in all structures of active RING/ U-Box E3/E2 pairs, as the linchpin for allosteric activation of E2~Ub. The conformational biasing mechanism is generalizable across diverse E2s and RING/U-box E3s, but is not shared by HECT-type E3s. The results provide a structural model for a RING/ U-box E3:E2~Ub ligase complex and identify the long sought-after source of allostery for RING/UBox activation of E2~Ub conjugates.

  1. High Resolution BPM Upgrade for the ATF Damping Ring at KEK

    SciTech Connect (OSTI)

    Eddy, N.; Briegel, C.; Fellenz, B.; Gianfelice-Wendt, E.; Prieto, P.; Rechenmacher, R.; Semenov, A.; Voy, D.; Wendt, M.; Zhang, D.; Terunuma, N.; /KEK, Tsukuba

    2011-08-17

    A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring has been accomplished, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R&D effort. The upgrade consists of a high resolution, high reproducibility read-out system, based on analog and digital down-conversion techniques, digital signal processing, and also implements a new automatic gain error correction schema. The technical concept and realization as well as results of beam studies are presented. The next generation of linear colliders require ultra-low vertical emittance of <2 pm-rad. The damping ring at the KEK Accelerator Test Facility (ATF) is designed to demonstrate this mission critical goal. A high resolution beam position monitor (BPM) system for the damping ring is one of the key tools for realizing this goal. The BPM system needs to provide two distnict measurements. First, a very high resolution ({approx}100-200nm) closed-orbit measurement which is averaged over many turns and realized with narrowband filter techniques - 'narrowband mode'. This is needed to monitor and steer the beam along an optimum orbit and to facilitate beam-based alignment to minimize non-linear field effects. Second, is the ability to make turn by turn (TBT) measurements to support optics studies and corrections necessary to achieve the design performance. As the TBT measurement necessitates a wider bandwidth, it is often referred to as 'wideband mode'. The BPM upgrade was initiated as a KEK/SLAC/FNAL collaboration in the frame of the Global Design Initiative of the International Linear Collider. The project was realized and completed using Japan-US funds with Fermilab as the core partner.

  2. Rotational fluxons of Bose-Einstein condensates in coplanar double-ring traps

    SciTech Connect (OSTI)

    Brand, J.; Haigh, T. J.; Zuelicke, U.

    2009-07-15

    Rotational analogs to magnetic fluxons in conventional Josephson junctions are predicted to emerge in the ground state of rotating tunnel-coupled annular Bose-Einstein condensates (BECs). Such topological condensate-phase structures can be manipulated by external potentials. We determine conditions for observing macroscopic quantum tunneling of a fluxon. Rotational fluxons in double-ring BECs can be created, manipulated, and controlled by external potentials in different ways than is possible in the solid-state system, thus rendering them a promising candidate system for studying and utilizing quantum properties of collective many-particle degrees of freedom.

  3. Design and Prototyping of an Ionization Profile Monitor for the SNS Accumulator Ring

    SciTech Connect (OSTI)

    Bartkoski, Dirk A; Deibele, Craig E; Polsky, Yarom

    2014-12-01

    An ionization profile monitor (IPM) has been designed for the Spallation Neutron Source (SNS) accumulator ring. Utilizing ionized electrons produced by beam-gas ionization, the SNS IPM uses a 120 kV bias potential to overcome beam space charge and accelerate electrons towards a movable particle detector. A 300 G magnetic field is used to confine the transverse electron motion, resulting in profile errors at the estimated 7% level. With a system bandwidth of 17.5 MHz. The SNS IPM is capable of measuring turn-by-turn beam profiles for a fully accumulated beam. This paper presents a description of the system and design.

  4. Lattice Design for PEP-X Ultimate Storage Ring Light Source

    SciTech Connect (OSTI)

    Bane, K.L.F.; Cai, Y.; Nosochkov, Y.; Wang, M.-H.; Hettel, R.O.; /SLAC

    2011-12-13

    SLAC expertise in designing and operating high current storage rings and the availability of the 2.2-km PEP-II tunnel present an opportunity for building a next generation light source - PEP-X - that would replace the SPEAR3 storage ring in the future. The PEP-X 'baseline' design, with 164 pm-rad emittance at 4.5 GeV beam energy and a current of 1.5 A, was completed in 2010. As a next step, a so-called 'ultimate' PEP-X lattice, reducing the emittance to 11 pm-rad at zero current, has been designed. This emittance approaches the diffraction limited photon emittance for multi-keV photons, providing near maximum photon brightness and high coherence. It is achieved by using 7-bend achromat cells in the ring arcs and a 90-m damping wiggler in one of the 6 long straight sections. Details of the lattice design, dynamic aperture, and calculations of the intra-beam scattering effect and Touschek lifetime at a nominal 0.2 A current are presented. Accelerator-based light sources are in high demand for many experimental applications. The availability of the 2.2-km PEP-II tunnel at SLAC presents an opportunity for building a next generation light source - PEP-X - that would replace the existing SPEAR3 light source in the future. The PEP-X study started in 2008, and the 'baseline' design, yielding 164 pm-rad emittance at 4.5 GeV beam energy and a current of 1.5 A, was completed in 2010. This relatively conservative design can be built using existing technology. However, for a long term future, it is natural to investigate a more aggressive, so-called 'ultimate' ring design. The goal is to reduce the electron emittance in both x and y planes to near the diffraction limited photon emittance of 8 pm-rad at hard X-ray photon wavelength of 0.1 nm. This would provide a near maximum photon brightness and significant increase in photon coherence. This study was motivated by the advances in low emittance design at MAX-IV. The latter was used as a starting point for the PEP-X arc lattice

  5. Safe operating conditions for NSLS-II Storage Ring Frontends commissioning

    SciTech Connect (OSTI)

    Seletskiy, S.; Amundsen, C.; Ha, K.; Hussein, A.

    2015-04-02

    The NSLS-II Storage Ring Frontends are designed to safely accept the synchrotron radiation fan produced by respective insertion device when the electron beam orbit through the ID is locked inside the predefined Active Interlock Envelope. The Active Interlock is getting enabled at a particular beam current known as AI safe current limit. Below such current the beam orbit can be anywhere within the limits of the SR beam acceptance. During the FE commissioning the beam orbit is getting intentionally disturbed in the particular ID. In this paper we explore safe operating conditions for the Frontends commissioning.

  6. Influence of graphene on quality factor variation in a silicon ring resonator

    SciTech Connect (OSTI)

    Kou, Rai; Tanabe, Shinichi; Hibino, Hiroki; Tsuchizawa, Tai; Yamada, Koji; Yamamoto, Tsuyoshi; Nakajima, Hirochika

    2014-03-03

    Selectively patterned graphene is integrated onto a silicon ring resonator to investigate the quality factor (Q factor) variation. The Q factor sharply decreases from 7900 to 1200 as the patterned graphene length increases from 0 to 20??m. A numerical estimation, which takes into account optical absorption by graphene, shows an exponential damping of the Q factor with increasing graphene length and is consistent with the experimental result. We expect these fundamental characterizations to be helpful in developing graphene-integrated silicon photonics applications.

  7. Using tevatron magnets for HE-LHC or new ring in LHC tunnel

    SciTech Connect (OSTI)

    Piekarz, Henryk; /Fermilab

    2011-08-01

    Two injector accelerator options for HE-LHC of p{sup +} - p{sup +} collisions at 33 TeV cms energy are briefly outlined. One option is based on the Super-SPS (S-SPS) accelerator in the SPS tunnel, and the other one is based on the LER (Low-Energy-Ring) accelerator in the LHC tunnel. Expectations of performance of the main arc accelerator magnets considered for the construction of the S-SPS and of the LER accelerators are used to tentatively devise some selected properties of these accelerators as potential injectors to HE-LHC.

  8. On linear groups of degree 2 over a finite commutative ring

    SciTech Connect (OSTI)

    Bashkirov, Evgenii L.; Eser, Hasan

    2014-08-20

    Let p > 3 be a prime number and F{sub p} be a field of p elements. Let K be a commutative and associative ring obtained by adjoining to F{sub p} an element α such that α satisfies a polynomial over F{sub p} and a polynomial of the least degree whose root is α can be written as a product of distinct polynomials irreducible over F{sub p}. We prove that the special linear group SL{sub 2}(K) is generated by two elementary transvections ( (table) ), ( (table) )

  9. Fine golden rings: Tunable surface plasmon resonance from assembled nanorods in topological defects of liquid crystals

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

    Lee, Elaine; Xia, Yu; Ferrier, Jr., Robert C.; Kim, Hye -Na; Gharbi, Mohamed A.; Stebe, Kathleen J.; Kamien, Randall D.; Composto, Russell J.; Yang, Shu

    2016-02-08

    Unprecedented, reversible, and dynamic control over an assembly of gold nanorods dispersed in liquid crystals (LC) is demonstrated. The LC director field is dynamically tuned at the nanoscale using microscale ring confinement through the interplay of elastic energy at different temperatures, thus fine-tuning its core replacement energy to reversibly sequester nanoscale inclusions at the microscale. As a result, this leads to shifts of 100 nm or more in the surface plasmon resonance peak, an order of magnitude greater than any previous work with AuNR composites.

  10. Method of polymerizing exo-methylene cyclic organic compounds using homogeneous ring-opening catalysts

    DOE Patents [OSTI]

    Marks, Tobin J.; Yang, Xinmin; Jia, Li

    1994-01-01

    The regiospecific (1,2-Me.sub.2 C.sub.5 H.sub.3).sub.2 ZrMe.sup.+ MeB(C.sub.6 F.sub.5).sub.3.sup.- mediated ring-opening polymerization of methylenecyclobutane and its copolymerization with ethylene to polyolefins of microstructure--{CH.sub.2 CH.sub.2 CH.sub.2 C(CH.sub.2)]--.sub.n and {--[CH.sub.2 CHR]--.sub.x [CH.sub.2 CH.sub.2 CH.sub.2 C(CH.sub.2)]--.sub.y }.sub.n' respectively, is disclosed.

  11. Progress on Optimization of the Nonlinear Beam Dynamics in the MEIC Collider Rings

    SciTech Connect (OSTI)

    Morozov, Vasiliy S.; Derbenev, Yaroslav S.; Lin, Fanglei; Pilat, Fulvia; Zhang, Yuhong; Cai, Y.; Nosochkov, Y. M.; Sullivan, Michael; Wang, M.-H.; Wienands, Uli

    2015-09-01

    One of the key design features of the Medium-energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab is a small beta function at the interaction point (IP) allowing one to achieve a high luminosity of up to 1034 cm-2s-1. The required strong beam focusing unavoidably causes large chromatic effects such as chromatic tune spread and beam smear at the IP, which need to be compensated. This paper reports recent progress in our development of a chromaticity correction scheme for the ion ring including optimization of dynamic aperture and momentum acceptance.

  12. A Test Facility for MEIC ERL Circulator Ring Based Electron Cooler Design

    SciTech Connect (OSTI)

    Zhang, Yuhong; Derbenev, Yaroslav S.; Douglas, David R.; Hutton, Andrew M.; Krafft, Geoffrey A.; Nissen, Edward W.

    2013-05-01

    An electron cooling facility which is capable to deliver a beam with energy up to 55 MeV and average current up to 1.5 A at a high bunch repetition rate up to 750 MHz is required for MEIC. The present cooler design concept is based on a magnetized photo-cathode SRF gun, an SRF ERL and a compact circulator ring. In this paper, we present a proposal of a test facility utilizing the JLab FEL ERL for a technology demonstration of this cooler design concept. Beam studies will be performed and supporting technologies will also be developed in this test facility.

  13. Confocal acoustic radiation force optical coherence elastography using a ring ultrasonic transducer

    SciTech Connect (OSTI)

    Qi, Wenjuan; Li, Rui; Ma, Teng; Kirk Shung, K.; Zhou, Qifa; Chen, Zhongping

    2014-03-24

    We designed and developed a confocal acoustic radiation force optical coherence elastography system. A ring ultrasound transducer was used to achieve reflection mode excitation and generate an oscillating acoustic radiation force in order to generate displacements within the tissue, which were detected using the phase-resolved optical coherence elastography method. Both phantom and human tissue tests indicate that this system is able to sense the stiffness difference of samples and quantitatively map the elastic property of materials. Our confocal setup promises a great potential for point by point elastic imaging in vivo and differentiation of diseased tissues from normal tissue.

  14. 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.

  15. Photoluminescence studies of individual and few GaSb/GaAs quantum rings

    SciTech Connect (OSTI)

    Young, M. P.; Woodhead, C. S.; Roberts, J.; Noori, Y. J.; Noble, M. T.; Krier, A.; Hayne, M.; Young, R. J.; Smakman, E. P.; Koenraad, P. M.

    2014-11-15

    We present optical studies of individual and few GaSb quantum rings embedded in a GaAs matrix. Contrary to expectation for type-II confinement, we measure rich spectra containing sharp lines. These lines originate from excitonic recombination and are observed to have resolution-limited full-width at half maximum of 200 ?eV. The detail provided by these measurements allows the characteristic type-II blueshift, observed with increasing excitation power, to be studied at the level of individual nanostructures. These findings are in agreement with hole-charging being the origin of the observed blueshift.

  16. Commissioning and Early Operation Experience of the NSLS-II Storage Ring RF System

    SciTech Connect (OSTI)

    Gao, F.; Rose, J.; Cupolo, J.; Dilgen, T.; Rose, B.; Gash, W.; Ravindranath, V.; Yeddulla, M.; Papu, J.; Davila, P.; Holub, B.; Tagger, J.; Sikora, R.; Ramirez, G.; Kulpin, J.

    2015-05-03

    The National Synchrotron Light Source II (NSLS-II) is a 3 GeV electron X-ray user facility commissioned in 2014. The storage ring RF system, essential for replenishing energy loss per turn of the electrons, consists of digital low level RF controllers, 310 kW CW klystron transmitters, CESR-B type superconducting cavities, as well as a supporting cryogenic system. Here we will report on RF commissioning and early operation experience of the system for beam current up to 200mA.

  17. Operation of a small-gap undulator on the NSLS X-ray Ring

    SciTech Connect (OSTI)

    Stefan, P.M.; Krinsky, S.; Rakowsky, G.; Solomon, L.

    1995-02-01

    The authors report results of an on-going experiment being carried out in the X13 straight section of the NSLS X-ray Ring which explores the limits of the operation of small-gap undulators. In particular, they discuss the operation of a 16 mm period small-gap undulator. At an electron beam current of 300 mA the variable gap vacuum chamber has been closed to an inner aperture of 3.8 mm with no effect on the electron beam lifetime. Measurements of the output radiation spectrum at a magnet gap of 7.5 mm are described.

  18. Single-parameter spin-pumping in driven metallic rings with spin-orbit coupling

    SciTech Connect (OSTI)

    Ramos, J. P.; Apel, V. M.; Foa Torres, L. E. F.; Orellana, P. A.

    2014-03-28

    We consider the generation of a pure spin-current at zero bias voltage with a single time-dependent potential. To such end we study a device made of a mesoscopic ring connected to electrodes and clarify the interplay between a magnetic flux, spin-orbit coupling, and non-adiabatic driving in the production of a spin and electrical current. By using Floquet theory, we show that the generated spin to charge current ratio can be controlled by tuning the spin-orbit coupling.

  19. CESR Conversion Damping Ring Studies of Electron Cloud Instabilities (CESR-TA)

    SciTech Connect (OSTI)

    Rubin, David L.; Palmer, Mark A.

    2011-08-02

    In the International Linear Collider, two linear accelerators will accelerate bunches of positrons and electrons to over a hundred billion electron volts and collide them in a central detector. In order to obtain useful collision rates, the bunches, each containing twenty billion particles, must be compressed to a cross section of a few nanometers by a few hundred nanometers. In order to prepare these ultra high density bunches, damping rings (DRs) are employed before the linear accelerators. The DRs take the high emittance bunches that are provided by the electron and positron sources and, through the process of radiation damping, squeeze them into ultra low emittance beams that are ready for the main linear accelerators. In the damping rings, a number of effects can prevent the successful preparation of the beams. In the electron ring, an effect known as the fast ion instability can lead to beam growth and, in the positron ring, the build-up of an electron cloud (EC), which interacts with the circulating bunches, can produce the same effect. EC build-up and the subsequent interaction of the cloud with the positron beam in the DR have been identified as major risks for the successful construction of a linear collider. The CESRTA research program at the Cornell Electron Storage Ring (CESR) was developed in order to study the build-up of the EC, the details of its impact on ultra low emittance beams, as well as methods to mitigate the impact of the cloud. In the DR, the EC forms when synchrotron photons radiated from the circulating beam strike the walls of the vacuum chamber, resulting in the emission of photoelectrons. These low energy electrons can be accelerated across the vacuum chamber by the electric field of the beam, and strike the walls, causing the emission of secondary electrons. The secondary electrons are subsequently accelerated into the walls yet again via the same mechanism. The result is that the EC can rapidly begin to fill the vacuum chamber. In

  20. NGC 4102: HIGH-RESOLUTION INFRARED OBSERVATIONS OF A NUCLEAR STARBURST RING

    SciTech Connect (OSTI)

    Beck, Sara C.; Lacy, John H.; Turner, Jean L.

    2010-10-20

    The composite galaxy NGC 4102 hosts a LINER nucleus and a starburst. We mapped NGC 4102 in the 12.8 {mu}m line of [Ne II], using the echelon spectrometer TEXES on the NASA IRTF, to obtain a data cube with 1.''5 spatial, and 25 km s{sup -1} spectral, resolution. Combining near-infrared, radio, and the [Ne II] data shows that the extinction to the starburst is substantial, more than 2 mag at the K band, and that the neon abundance is less than half solar. We find that the star formation in the nuclear region is confined to a rotating ring or disk of 4.''3 ({approx}300 pc) diameter, inside the inner Lindblad resonance. This region is an intense concentration of mass, with a dynamical mass {approx}3 x 10{sup 9} M{sub sun}, and of star formation. The young stars in the ring produce the [Ne II] flux reported by Spitzer for the entire galaxy. The mysterious blue component of line emission detected in the near-infrared is also seen in [Ne II]; it is not a normal active galactic nucleus outflow.

  1. Separation, characterization and instrumental analysis of polynuclear aromatic hydrocarbon ring classes in petroleum

    SciTech Connect (OSTI)

    Chmielowiec, J.; Beshai, J.E.; George, A.E.

    1980-08-01

    To develop effective utilization technology for heavy streams from conventional fuels and unconventional resources such as heavy oils and oilsand bitumens, detailed information on the chemical composition of the feedstocks is needed. Attempts were made during the seventies to modify the API Project 60 scheme of analysis or to develop chemically more efficient, and less time-consuming, separation and characterization methods. These attempts aimed to improve characterization by separating the samples into concentrates of different structural types. Samples throughput was increased by using pressure and higher performance chromatographic systems. Other valuable contributions, such as coal-liquid characterization in terms of different chemical functionalities have also been made. The separation of aromatic ring classes and characterization or identification of their major components was our primary objective in this study. A silica-R(NH/sub 2/)/sub 2/-based HPLC system was used in our laboratory to study the analytical potential of this approach; the work was described in a previous publication. In the present study, the applicability of HPLC separation by this system and instrumental spectrometric characterization of 3- and 4-ring PAHs isolated from two Canadian oils were investigated. The oils used, Medicine River and Lloydminster, are examples of hydrocarbon-dominated materials representing light and heavy processing feedstocks, respectively.

  2. The large superconducting solenoids for the g-2 muon storage ring

    SciTech Connect (OSTI)

    Bunce, G.; Cullen, J.; Danby, G.

    1994-12-01

    The g-2 muon storage ring at Brookhaven National Laboratory consists of four large superconducting solenoids. The two outer solenoids, which are 15.1 meters in diameter, share a common cryostat. The two inner solenoids, which are 13.4 meters in diameter, are in separate cryostats. The two 24 turn inner solenoids are operated at an opposite polarity from the two 24 turn outer solenoids. This generates a dipole field between the inner and outer solenoids. The flux between the solenoids is returned through a C shaped iron return yoke that also shapes the dipole field. The integrated field around the 14 meter diameter storage ring must be good to about 1 part in one million over the 90 mm dia. circular cross section where the muons are stored, averaged over the azimuth. When the four solenoids carry their 5300 A design current, the field in the 18 centimeter gap between the poles is 1.45 T. When the solenoid operates at its design current 5.5 MJ is stored between the poles. The solenoids were wound on site at Brookhaven National Laboratory. The cryostats were built around the solenoid windings which are indirectly cooled using two-phase helium.

  3. Waveguide Structures for RF Undulators with Applications to FELs and Storage Rings

    SciTech Connect (OSTI)

    Yeddulla, M.; Geng, H.G.; Huang, Z.; Ma, Z.; Tantawi, S.G.; /SLAC

    2011-11-02

    RF undulators, suggested a long time ago, have the advantage of fast dynamic control of polarization, undulator strength and wavelength. However, RF undulators require very strong RF fields in order to produce radiation of the same order as conventional static devices. Very high power RF energy confined inside a waveguide or a cavity can provide the necessary RF fields to undulate the electron beam. However, the wall losses in the waveguide should be low enough to make it practically feasible as a CW or quasi CW undulator and, hence, competitive with static devices for applications to storage rings and FELs. Here we present various waveguide structures such as smooth walled and corrugated walled waveguides and various RF modes. We will show that there are some advantages in operating with higher order modes and also with hybrid modes in the corrugated guide. We will show that the RF power requirement for some of these modes will permit a quasi CW operation of the undulator, thus permitting its operation in a storage ring.

  4. Molecular hydrogen maps of extended planetary nebulae - the Dumbbell, the Ring, and NGC 2346

    SciTech Connect (OSTI)

    Zuckerman, B.; Gatley, I.

    1988-01-01

    The 3.8-m United Kingdom Infrared Telecsope at Mauna Kea was used to obtain complete H2 maps of three extended planetary nebulae (PNs) that are representative of two of the most common PN morphologies, bow tie and bipolar ring: the Dumbbell (NGC 6853), the Ring (NGC 6720), and the NG 2346, are discussed. The results of map analysis indicates that the S(1) emission from H2 closely follows the optical morphology of the three nebulae. The H2 emission is more extended than the main emitting mass of ionized gas and, in NGCC 2346, there is evidence for a dense torus of hot H2 surrounding the central star. The H2 emissionl appears to be shock-excited. Examinations of existing H2 measurements indicate that strong H2 emission is preferentially present in PNs that lie at small galactic latitude, implying that massive main-sequence stars produce ionization-bounded PNs, whereas low-mass stars produce density-bounded PNs. Thus, maps of H2 emission may not only be used to determine whether a given PN is ionization-bounded or density-bounded, but also to estimate the mass of the progenitor star. 83 references.

  5. Present status of the NIJI-IV storage-ring free-electron lasers

    SciTech Connect (OSTI)

    Yamazaki, T.; Yamada, K.; Sei, N.

    1995-12-31

    The tunable region of the free-electron-laser (FEL) wavelength with the NIJI-IV system is now 348{approximately}595 nm. After the lasing at 352 nm in 1994, the quality of the electron beam stored in the ring has been improved further, and the highest peak intensity of the laser obtained so far is more than 300 times as high as that of the resonated spontaneous emission. The macro-temporal structure of the lasing has been greatly improved. Recently, a single-bunch injection system was completed, and the system has been installed in the injector linac, which is expected to increase the peak stored-beam current. The commissioning and the test of the new system is under way. The beam transporting system from the linac to the ring is also being modified by increasing the number of quadrupole magnets. The experiments related to the FEL in the ultraviolet wavelength region will be begun in this coming May. The results and the status of the FEL experiments will be presented at the Conference.

  6. Magnetic confinement in a ring-cusp ion thruster discharge plasma

    SciTech Connect (OSTI)

    Sengupta, Anita

    2009-05-01

    An experimental investigation, in conjunction with a volume averaged analytical model, has been developed to improve the confinement and production of the discharge plasma for plasma thrusters and ion sources. The research conducted explores the discharge performance of a ring-cusp ion source based on the magnetic field configuration, geometry, and power level. Analytical formulations for electron and ion confinement are developed to predict the ionization efficiency for a given discharge chamber design. Explicit determination of discharge loss and volume averaged plasma parameters are obtained via a series of experimental measurements on a ring-cusp NASA Solar Technology Application Readiness (NSTAR) ion thruster to assess the validity of the analytical model. Measurements of the discharge loss with multiple magnetic field configurations compare well with plasma parameter predictions for propellant utilizations between 80% and 95%. The results indicate that increasing the magnetic strength of the first closed magnetic contour line reduces Maxwellian electron diffusion and electrostatically confines the ion population and subsequent loss to the anode wall. The results also indicate that increasing the strength and minimizing the area of the magnetic cusps improves primary electron confinement, increasing the probability of an ionization collision prior to loss at the cusp.

  7. AGING BEHAVIOR OF VITON O-RING SEALS IN THE 9975 SHIPPING PACKAGE

    SciTech Connect (OSTI)

    Skidmore, E.; Daugherty, W.; Hoffman, E.; Dunn, K.; Bellamy, S.

    2012-01-13

    The Savannah River Site (SRS) is storing plutonium (Pu) materials in the K-Area Materials Storage (KAMS) facility. The Pu materials were packaged according to the DOE-STD-3013 standard and shipped to the SRS in Type B 9975 packages. The robust 9975 shipping package was not designed for long-term product storage, but it is a specified part of the storage configuration and the KAMS facility safety basis credits the 9975 design with containment. Within the 9975 package, nested stainless steel containment vessels are closed with dual O-ring seals based on Viton{reg_sign} GLT or GLT-S fluoroelastomer. The aging behavior of the O-ring compounds is being studied to provide the facility with advanced notice of nonconformance and to develop life prediction models. A combination of field surveillance, leak testing of surrogate fixtures aged at bounding service temperatures, and accelerated-aging methodologies based on compression stress-relaxation and oxygen consumption analysis is being used to evaluate seal performance. A summary of the surveillance program relative to seal aging behavior is presented.

  8. Open loop compensation for the eddy current effect in the APS storage ring vacuum chamber

    SciTech Connect (OSTI)

    Chung, Y.; Bridges, J.; Emery, L.; Decker, G.

    1991-01-01

    In the third generation synchrotron light sources, closed orbit stabilization against external vibrations is critical to ensure low emittance and high brightness. The Advanced Photon Source (APS) will use a large number (678) of correction magnets to create local bumps and to achieve global orbit stabilization. In this paper, we will present the result of the effort to counter the effect due to the finite inductance of the magnet and the eddy current in the 1/2 in.-thick aluminum storage ring vacuum chamber. The amplitude attenuation and the phase shift of the correction magnet field inside the APS storage ring vacuum chamber were measured. A circuit to compensate for this effect was then inserted between the signal source and the magnet power supply. The amplitude was restored with an error of less than 20% of the source signal amplitude and the phase shift was reduced from 80{degrees} to 12{degrees} at 10 Hz. Incorporation of this circuit in the closed loop feedback scheme and the resulting beneficial effect in the closed orbit stabilization will be discussed. 4 refs., 4 figs.

  9. Harmonic Resonant Kicker Design for the MEIC Electron Circular Cooler Ring

    SciTech Connect (OSTI)

    Huang, Yulu; Wang, Haipeng; Rimmer, Robert A.

    2015-09-01

    Bunched-beam electron cooling of the high-energy ion beam emittance may be a crucial technology for the proposed Medium energy Electron Ion Collider (MEIC) to achieve its design luminosity. A critical component is a fast kicker system in the Circular Ring (CR) that periodically switches electron bunches in and out of the ring from and to the driver Energy Recovery Linac (ERL). Compared to a conventional strip-line type kicker, a quarter wave resonator (QWR) based deflecting structure has a much higher shunt impedance and so requires much less RF power. The cavity has been designed to resonate simultaneously at many harmonic modes that are integer multiples of the fundamental mode. In this way the resulting waveform will kick only a subset of the circulating bunches. In this paper, analytical shunt impedance optimization, the electromagnetic simulations of this type of cavity, as well as tuner and coupler concept designs to produce 5 odd and 5 even harmonics of 47.63MHz will be presented, in order to kick every 10th bunch in a 476.3 MHz bunch train.

  10. Six-Membered-Ring Malonatoborate-Based Lithium Salts as Electrolytes for Lithium Ion Batteries

    SciTech Connect (OSTI)

    Yang, Li; Zhang, Hanjun; Driscoll, Peter; Lucht, Brett; Kerr, John

    2011-09-30

    A new class of lithium salts of malonatoborate anions has been synthesized. These six-membered-ring salts provided slightly lower ionic conductivity than that of LiBOB and LiBF4. Nevertheless, compared with LiBOB and LiPF6, the lowered ring strains in the malonatoborate structures and reduced numbers of fluorine atoms in the molecules was found to enhance the thermal and water stabilities and compatibilities of these salts with ether solvents. Small amount LiDMMDFB when used as an additive, was found to stabilize LiPF6 in carbonate electrolytes at 80°C for one month. Employing LiMDFB as the electrolyte in Li/Li cells and full cells, large interfacial impedances were observed on lithium metal and the cathode. Moreover, the large impedances are at least partially attributed to the acidic hydrogen atoms in the malonate structure. This issue can be addressed by replacing the acidic atoms with methyl groups.

  11. Use of the Halbach perturbation theory for the multipole design of the ALS storage ring sextupole

    SciTech Connect (OSTI)

    Marks, S.

    1995-02-01

    The Advanced Light Source (ALS) storage ring sextupole is a unique multi-purpose magnet. It is designed to operate in the primary or sextupole mode and in three auxiliary trim modes: horizontal steering, vertical steering, and skew quadrupole. Klaus Halbach developed a perturbation theory for iron-dominated magnets which provides the basis for this design. Many magnet designers, certainly those who have been exposed to Klaus, are familiar with this theory and have used it for such things as evaluating the effect of assembly alignment errors. The ALS sextupole design process was somewhat novel in its use of the perturbation theory to design essential features of the magnet. In particular, the steering and skew quadrupole functions are produced by violating sextupole symmetry and are thus perturbations of the normal sextupole excitation. The magnet was designed such that all four modes are decoupled and can be excited independently. This paper discusses the use of Halbach`s perturbation theory to design the trim functions and to evaluate the primary asymmetry in the sextupole mode, namely, a gap in the return yoke to accommodate the vacuum chamber. Prototype testing verified all operating modes of the magnet and confirmed the expected performance from calculations based upon the Halbach perturbation theory. A total of 48 sextupole magnets of this design are now installed and operating successfully in the ALS storage ring.

  12. EXTREMELY RAPID STAR CLUSTER DISRUPTION IN HIGH-SHEAR CIRCUMNUCLEAR STARBURST RINGS: THE UNUSUAL CASE OF NGC 7742

    SciTech Connect (OSTI)

    De Grijs, Richard; Anders, Peter E-mail: anders@pku.edu.cn

    2012-10-10

    All known mass distributions of recently formed star cluster populations resemble a 'universal' power-law function. Here we assess the impact of the extremely disruptive environment in NGC 7742's circumnuclear starburst ring on the early evolution of the galaxy's high-mass ({approx}10{sup 5}-10{sup 7} M{sub Sun }) star cluster population. Surprisingly, and contrary to expectations, at all ages-including the youngest, {approx}< 15 Myr-the cluster mass functions are robustly and verifiably represented by lognormal distributions that resemble those commonly found only for old, evolved globular cluster systems in the local universe. This suggests that the high-shear conditions in the NGC 7742 starburst ring may significantly speed up dynamical star cluster destruction. This enhanced mass-dependent disruption rate at very young ages might be caused by a combination of the starburst ring's high density and the shear caused by the counterrotating gas disk.

  13. Low temperature spin dynamics in Cr{sub 7}Ni-Cu-Cr{sub 7}Ni coupled molecular rings

    SciTech Connect (OSTI)

    Bordonali, L.; Furukawa, Y.; Mariani, M.; Sabareesh, K. P. V.; Garlatti, E.; Borsa, F.

    2014-05-07

    Proton Nuclear Magnetic Resonance (NMR) relaxation measurements have been performed down to very low temperature (50 mK) to determine the effect of coupling two Cr{sub 7}Ni molecular rings via a Cu{sup 2+} ion. No difference in the spin dynamics was found from nuclear spin lattice relaxation down to 1.5 K. At lower temperature, the {sup 1}H-NMR line broadens dramatically indicating spin freezing. From the plot of the line width vs. magnetization, it is found that the freezing temperature is higher (260 mK) in the coupled ring with respect to the single Cr{sub 7}Ni ring (140 mK)

  14. Peroxynitrite-induced relaxation in isolated rat aortic rings and mechanisms of action

    SciTech Connect (OSTI)

    Li Jianfeng; Li Wenyan; Altura, Bella T.; Altura, Burton M. . E-mail: baltura@downstate.edu

    2005-12-15

    The present study was designed to evaluate the effects of peroxynitrite (ONOO{sup -}), the product of superoxide and nitric oxide, on isolated segments of rat aorta. In the absence of any vasoactive agent, ONOO{sup -} (from 10{sup -8} to 10{sup -4} M) failed to alter the basal tension. In phenylephrine (PE; 5 x 10{sup -7} M)-precontracted rat aortic rings (RAR), ONOO{sup -} elicited concentration-dependent relaxation at concentrations of from 10{sup -8} to 10{sup -4} M. The effective concentrations producing approximately 50% of maximal relaxation (ED{sub 5}) to ONOO{sup -} were 1.84 x 10{sup -5} M and 1.96 x 10{sup -5} M in intact and denuded RAR, respectively (P > 0.05). No significant differences in the relaxation responses were found between RAR with or without endothelium (P > 0.05). The presence of either 5 {mu}M methylene blue (MB) or 5 {mu}M 1H-[1,2,4]oxadiazolo-[4,3-{alpha}]quinoxalin-1-one (ODQ) significantly inhibited the relaxations induced by ONOO{sup -}. Sildenafil (10{sup -7} M), on the other hand, significantly potentiated the ONOO{sup -}-induced relaxations. Tetraethylammonium chloride (T-2265) significantly decreased the ONOO{sup -}-induced relaxations in a concentration-dependent manner. However, ONOO{sup -} had no effect on RAR precontracted by high KCL (40 mM, n = 6, P > 0.05). Addition of calyculin A also significantly decreased the ONOO{sup -}-induced relaxation in a dose-dependent manner. Furthermore, ONOO{sup -} significantly inhibited calcium-induced contractions of K{sup +}-depolarized aortic rings in a concentration-related manner. Lastly, a variety of other pharmacological agents and antagonists including L-NMMA, L-arginine, indomethacin, atropine, naloxone, diphenhydramine, cimetine, glibenclamide, haloperidol, superoxide dismutase (SOD), and catalase did not influence the relaxant effects of ONOO{sup -} on RAR. Our new results suggest that ONOO{sup -}-triggered relaxation on rat aortic rings is mediated by elevation of cGMP levels

  15. Comparison of ring compression testing to three point bend testing for unirradiated ZIRLO cladding

    SciTech Connect (OSTI)

    None, None

    2015-04-01

    Safe shipment and storage of nuclear reactor discharged fuel requires an understanding of how the fuel may perform under the various conditions that can be encountered. One specific focus of concern is performance during a shipment drop accident. Tests at Savannah River National Laboratory (SRNL) are being performed to characterize the properties of fuel clad relative to a mechanical accident condition such as a container drop. Unirradiated ZIRLO tubing samples have been charged with a range of hydride levels to simulate actual fuel rod levels. Samples of the hydrogen charged tubes were exposed to a radial hydride growth treatment (RHGT) consisting of heating to 400°C, applying initial hoop stresses of 90 to 170 MPa with controlled cooling and producing hydride precipitates. Initial samples have been tested using both a) ring compression test (RCT) which is shown to be sensitive to radial hydride and b) three-point bend tests which are less sensitive to radial hydride effects. Hydrides are generated in Zirconium based fuel cladding as a result of coolant (water) oxidation of the clad, hydrogen release, and a portion of the released (nascent) hydrogen absorbed into the clad and eventually exceeding the hydrogen solubility limit. The orientation of the hydrides relative to the subsequent normal and accident strains has a significant impact on the failure susceptability. In this study the impacts of stress, temperature and hydrogen levels are evaluated in reference to the propensity for hydride reorientation from the circumferential to the radial orientation. In addition the effects of radial hydrides on the Quasi Ductile Brittle Transition Temperature (DBTT) were measured. The results suggest that a) the severity of the radial hydride impact is related to the hydrogen level-peak temperature combination (for example at a peak drying temperature of 400°C; 800 PPM hydrogen has less of an impact/ less radial hydride fraction than 200 PPM hydrogen for the same thermal

  16. A self-injected, diode-pumped, solid-state ring laser for laser cooling of Li atoms

    SciTech Connect (OSTI)

    Miake, Yudai; Mukaiyama, Takashi; O’Hara, Kenneth M.; Gensemer, Stephen

    2015-04-15

    We have constructed a solid-state light source for experiments with laser cooled lithium atoms based on a Nd:Y V O{sub 4} ring laser with second-harmonic generation. Unidirectional lasing, an improved mode selection, and a high output power of the ring laser were achieved by weak coupling to an external cavity which contained the lossy elements required for single frequency operation. Continuous frequency tuning is accomplished by controlling two piezoelectric transducers (PZTs) in the internal and the external cavities simultaneously. The light source has been utilized to trap and cool fermionic lithium atoms into the quantum degenerate regime.

  17. Simultaneous linear optics and coupling correction for storage rings with turn-by-turn beam position monitor data

    SciTech Connect (OSTI)

    Yang, Xi; Huang, Xiaobiao

    2015-11-10

    We propose a method to simultaneously correct linear optics errors and linear coupling for storage rings using turn-by-turn (TbT) beam position monitor (BPM) data. The independent component analysis (ICA) method is used to isolate the betatron normal modes from the measured TbT BPM data. The betatron amplitudes and phase advances of the projections of the normal modes on the horizontal and vertical planes are then extracted, which, combined with dispersion measurement, are used to fit the lattice model. Furthermore, the fitting results are used for lattice correction. Our method has been successfully demonstrated on the NSLS-II storage ring.

  18. Aging Study Of EPDM O-Ring Material For The H1616 Shipping Package - Three Year Status

    SciTech Connect (OSTI)

    Stefek, T.; Daugherty, W.; Skidmore, E.

    2015-11-05

    This is a 3-year status report for tasks carried out per Task Technical Plan SRNL-STI-2011-00506. A series of tasks/experiments were performed at the Savannah River National Laboratory (SRNL) to monitor the aging performance of ethylene propylene diene monomer (EPDM) O-rings used in the H1616 shipping package. The test data provide a technical basis to extend the annual maintenance of the H1616 shipping package to three years and to predict the life of the EPDM O-rings at the bounding service conditions.

  19. Efficient graphite ring heater suitable for diamond-anvil cells to 1300 K

    SciTech Connect (OSTI)

    Du Zhixue; Amulele, George; Lee, Kanani K. M.; Miyagi, Lowell

    2013-02-15

    In order to generate homogeneous high temperatures at high pressures, a ring-shaped graphite heater has been developed to resistively heat diamond-anvil cell (DAC) samples up to 1300 K. By putting the heater in direct contact with the diamond anvils, this graphite heater design features the following advantages: (1) efficient heating: sample can be heated to 1300 K while the DAC body temperature remains less than 800 K, eliminating the requirement of a special alloy for the DAC; (2) compact design: the sample can be analyzed with in situ measurements, e.g., x-ray, optical, and electrical probes are possible. In particular, the side access of the heater allows for radial x-ray diffraction (XRD) measurements in addition to traditional axial XRD.

  20. Narrow band wavelength selective filter using grating assisted single ring resonator

    SciTech Connect (OSTI)

    Prabhathan, P. Murukeshan, V. M.

    2014-09-15

    This paper illustrates a filter configuration which uses a single ring resonator of larger radius connected to a grating resonator at its drop port to achieve single wavelength selectivity and switching property with spectral features suitable for on-chip wavelength selection applications. The proposed configuration is expected to find applications in silicon photonics devices such as, on-chip external cavity lasers and multi analytic label-free biosensors. The grating resonator has been designed for a high Q-factor, high transmittivity, and minimum loss so that the wavelength selectivity of the device is improved. The proof-of-concept device has been demonstrated on a Silicon-on-Insulator (SOI) platform through electron beam lithography and Reactive Ion Etching (RIE) process. The transmission spectrum shows narrow band single wavelength selection and switching property with a high Free Spectral Range (FSR) ?60 nm and side band rejection ratio >15 dB.

  1. Antiferromagnetic resonance excitation by terahertz magnetic field resonantly enhanced with split ring resonator

    SciTech Connect (OSTI)

    Mukai, Y.; Hirori, H.; Yamamoto, T.; Kageyama, H.; Tanaka, K.

    2014-07-14

    Excitation of antiferromagnetic resonance (AFMR) in a HoFeO{sub 3} crystal combined with a split ring resonator (SRR) is studied using terahertz (THz) electromagnetic pulses. The magnetic field in the vicinity of the SRR is induced by the incident THz electric field component and excites spin oscillations that correspond to the AFMR, which are directly probed by the Faraday rotation of the polarization of a near-infrared probe pulse. The good agreement of the temperature-dependent magnetization dynamics with the calculation using the two-lattice Landau-Lifshitz-Gilbert equation confirms that the AFMR is excited by the THz magnetic field, which is enhanced at the SRR resonance frequency by a factor of 20 compared to the incident magnetic field.

  2. Measurements of aperture and beam lifetime using movable beam scrapers in Indus-2 electron storage ring

    SciTech Connect (OSTI)

    Kumar, Pradeep; Ghodke, A. D.; Karnewar, A. K.; Holikatti, A. C.; Yadav, S.; Puntambekar, T. A.; Singh, G.; Singh, P.

    2013-12-15

    In this paper, the measurements of vertical and horizontal aperture which are available for stable beam motion in Indus-2 at beam energy 2.5 GeV using movable beam scrapers are presented. These beam scrapers are installed in one of the long straight sections in the ring. With the movement of beam scrapers towards the beam centre, the beam lifetime is measured. The beam lifetime data obtained from the movement of vertical and horizontal beam scrapers are analyzed. The contribution of beam loss due to beam-gas scattering (vacuum lifetime) and electron-electron scattering within a beam bunch (Touschek lifetime) is separated from the measured beam lifetime at different positions of the beam scrapers. Vertical and horizontal beam sizes at scrapers location are estimated from the scraper movement towards the beam centre in quantum lifetime limit and their values closely agree with measured value obtained using X-ray diagnostic beamline.

  3. POWER SUPPLY CONTROL AND MONITORING FOR THE SNS RING AND TRANSPORT SYSTEM

    SciTech Connect (OSTI)

    LAMBIASE,R.; OERTER,B.; PENG,S.; SMITH,J.

    2001-06-28

    There are approximately 300 magnet power supplies in the SNS accumulator ring and transport lines. Control and monitoring of the these converters will be primarily accomplished with a new Power Supply Interface and Controller (PSI/PSC) system developed for the SNS project. This PSI/PSC system provides all analog and digital commands and status readbacks in one fiber isolated module. With a maximum rate of 10KHz, the PSI/PSC must be supplemented with higher speed systems for the wide bandwidth pulsed injection supplies, and the even wider bandwidth extraction kickers. This paper describes the implementation of this PSI/PSC system, which was developed through an industry/laboratory collaboration, and the supplementary equipment used to support the wider bandwidth pulsed supplies.

  4. Bohm-Aharonov and Kondo effects on tunneling currents in a mesoscopic ring

    SciTech Connect (OSTI)

    Davidovich, M.A.; Anda, E.V.; Chiappe, G.

    1997-03-01

    We present an analysis of the Kondo effect on the Bohm-Aharonov oscillations of the tunneling currents in a mesoscopic ring with a quantum dot inserted in one of its arms. The system is described by an Anderson-impurity tight-binding Hamiltonian where the electron-electron interaction is restricted to the dot. The currents are obtained using nonequilibrium Green functions calculated through a cumulant diagrammatic expansion in the chain approximation. It is shown that at low temperature, even with the system out of resonance, the Kondo peak provides a channel for the electron to tunnel through the dot, giving rise to the Bohm-Aharonov oscillations of the current. At high temperature these oscillations are important only if the dot level is aligned to the Fermi level, when the resonance condition is satisfied. {copyright} {ital 1997} {ital The American Physical Society}

  5. A Pulsed Modulator Power Supply for the g-2 Muon Storage Ring Injection Kicker

    SciTech Connect (OSTI)

    Mi,J.; Lee, Y.Y.; Morse, W. M.; Pai, C.; Pappas, G.; Sanders, R.; Semertzidis, Y.

    1999-03-29

    This paper describes the pulse modulator power supplies used to drive the kicker magnets that inject the muon beam into the g-2 storage ring that has been built at Brookhaven. Three modulators built into coaxial structures consisting of a series circuit of an energy storage capacitor, damping resistor and a fast thyratron switch are used to energize three magnets that kick the beam into the proper orbit. A 100 kV charging power supply is used to charge the capacitor to 95 kV. the damping resistor shapes the magnet current waveform to a 450 nanosecond half-sine to match the injection requirements. this paper discusses the modulator design, construction and operation.

  6. A PULSED MODULATOR POWER SUPPLY FOR THE G-2 MUON STORAGE RING INJECTION KICKER.

    SciTech Connect (OSTI)

    MI,J.LEE,Y.Y.MORSE,W.M.PAI,C.I.PAPPAS,G.C.SANDERS,Y.SEMERTIZIDIS,Y.,ET AL.

    2003-03-01

    This paper describes the pulse modulator power supplies used to drive the kicker magnets that inject the muon beam into the 8-2 storage ring that has been built at Brookhaven National Laboratory. Three modulators built into coaxial structures consisting of a series circuit of an energy storage capacitor, a damping resistor and a fast thyratron switch are used to energize three magnets that kick the beam into the proper orbit. A 100 kV charging power supply is used to charge the capacitor to 95kV. The damping resistor shapes the magnet current waveform to a 450 nanosecond half-sine to match the injection requirements. This paper discusses the modulator design, construction and operation.

  7. Chaotic parametric soliton-like pulses in ferromagnetic-film active ring resonators

    SciTech Connect (OSTI)

    Grishin, S. V. Golova, T. M.; Morozova, M. A.; Romanenko, D. V.; Seleznev, E. P.; Sysoev, I. V.; Sharaevskii, Yu. P.

    2015-10-15

    The generation of quasi-periodic sequences of parametric soliton-like pulses in an active ring resonator with a ferromagnetic film via the three-wave parametric instability of a magnetostatic surface wave is studied theoretically and experimentally. These dissipative structures form in time due to the competition between the cubic nonlinearity caused by parametric coupling between spin waves and the time dispersion caused by the resonant cavity that is present in a self-oscillatory system. The development of dynamic chaos due to the parametric instability of a magnetostatic surface wave results in irregular behavior of a phase. However, this behavior does not break a quasi-periodic pulse sequence when the gain changes over a wide range. The generated soliton-like pulses have a chaotic nature, which is supported by the maximum Lyapunov exponent estimated from experimental time series.

  8. Circuit model optimization of a nano split ring resonator dimer antenna operating in infrared spectral range

    SciTech Connect (OSTI)

    Gneiding, N.; Zhuromskyy, O.; Peschel, U.; Shamonina, E.

    2014-10-28

    Metamaterials are comprised of metallic structures with a strong response to incident electromagnetic radiation, like, for example, split ring resonators. The interaction of resonator ensembles with electromagnetic waves can be simulated with finite difference or finite elements algorithms, however, above a certain ensemble size simulations become inadmissibly time or memory consuming. Alternatively a circuit description of metamaterials, a well developed modelling tool at radio and microwave frequencies, allows to significantly increase the simulated ensemble size. This approach can be extended to the IR spectral range with an appropriate set of circuit element parameters accounting for physical effects such as electron inertia and finite conductivity. The model is verified by comparing the coupling coefficients with the ones obtained from the full wave numerical simulations, and used to optimize the nano-antenna design with improved radiation characteristics.

  9. Solar heating of the Uranian mesopause by dust of ring origin

    SciTech Connect (OSTI)

    Rizk, B.; Hunten, D.M. )

    1990-12-01

    Submicron dust absorption of visible-wavelength solar energy, in conjunction with inhibition of IR radiation, is assumed in the present estimate of the magnitude of an equatorial heat source due to such dust in the upper atmosphere of Uranus. The dust is noted to be capable of generating enough mesopause-level heat to account for heat sources observed only near the equator. Such dust is nevertheless excluded as a heat source for the 500-800 K thermospheric temperatures recorded by the Voyager UV spectrometer. The influx needed for a significant heat source corresponds to decomposition into submicron dust of about 100, 10-km diameter moons with 1.5 g/cu cm density; this is a plausible average dust flux for the rings of Uranus. 32 refs.

  10. Solid optical ring interferometer for high-throughput feedback-free spectral analysis and filtering

    SciTech Connect (OSTI)

    Petrak, B.; Peiris, M.; Muller, A.

    2015-02-15

    We describe a simple and inexpensive optical ring interferometer for use in high-resolution spectral analysis and filtering. It consists of a solid cuboid, reflection-coated on two opposite sides, in which constructive interference occurs for waves in a rhombic trajectory. Due to its monolithic design, the interferometers resonance frequencies are insensitive to environmental disturbances over time. Additional advantages are its simplicity of alignment, high-throughput, and feedback-free operation. If desired, it can be stabilized with a secondary laser without disturbance of the primary signal. We illustrate the use of the interferometer for the measurement of the spectral Mollow triplet from a quantum dot and characterize its long-term stability for filtering applications.

  11. Characterization of beam dynamics in the APS injector rings using time-resolved imaging techniques

    SciTech Connect (OSTI)

    Yang, B.X.; Lumpkin, A.H.; Borland, M.

    1997-06-01

    Images taken with streak cameras and gated intensified cameras with both time (longitudinal) and spatial (transverse) resolution reveal a wealth of information about circular accelerators. The authors illustrate a novel technique by a sequence of dual-sweep streak camera images taken at a high dispersion location in the booster synchrotron, where the horizontal coordinate is strongly correlated with the particle energy and the {open_quotes}top-view{close_quotes} of the beam gives a good approximation to the particle density distribution in the longitudinal phase space. A sequence of top-view images taken fight after injection clearly shows the beam dynamics in the phase space. We report another example from the positron accumulator ring for the characterization of its beam compression bunching with the 12th harmonic rf.

  12. Lattice design and optimization for the PEP-X ultra low emittance storage ring at SLAC

    SciTech Connect (OSTI)

    Wang, Min-Huey; Nosochkov, Yuri; Bane, Karl; Cai, Yunhai; Hettel, Robert; Huang, Xiaobiao; /SLAC

    2011-08-12

    SLAC is developing a long-range plan to transfer the evolving scientific programs at SSRL from the SPEAR3 light source to a much higher performing photon source. One of the possibilities is a new PEP-X 4.5 GeV storage ring that would be housed in the 2.2 km PEP-II tunnel. The PEP-X is designed to produce photon beams having brightness near 10{sup 22} (ph/s/mm{sup 2}/mrad{sup 2}/0.1% BW) at 10 keV with 3.5 m undulator at beam current of 1.5 A. This report presents an overview of the PEP-X baseline lattice design and describes the lattice optimization procedures in order to maximize the beam dynamic aperture. The complete report of PEP-X baseline design is published in SLAC report.

  13. Investigation of the fracture and fragmentation of explosively driven rings and cylinders

    SciTech Connect (OSTI)

    Goto, D M; Becker, R C; Orzechowski, T J; Springer, H K; Sunwoo, A J; Syn, C K

    2007-04-18

    Cylinders and rings fabricated from AerMet{reg_sign} 100 alloy and AISI 1018 steel have been explosively driven to fragmentation in order to determine the fracture strains for these materials under plane strain and uniaxial stress conditions. The phenomena associated with the dynamic expansion and subsequent break up of the cylinders are monitored with high-speed diagnostics. In addition, complementary experiments are performed in which fragments from the explosively driven cylinders are recovered and analyzed to determine the statistical distribution associated with the fragmentation process as well as to determine failure mechanisms. The data are used to determine relevant coefficients for the Hancock-McKenzie (Johnson-Cook) fracture model. Metallurgical analysis of the fragments provides information on damage and failure mechanisms.

  14. Software package for modeling spin–orbit motion in storage rings

    SciTech Connect (OSTI)

    Zyuzin, D. V.

    2015-12-15

    A software package providing a graphical user interface for computer experiments on the motion of charged particle beams in accelerators, as well as analysis of obtained data, is presented. The software package was tested in the framework of the international project on electric dipole moment measurement JEDI (Jülich Electric Dipole moment Investigations). The specific features of particle spin motion imply the requirement to use a cyclic accelerator (storage ring) consisting of electrostatic elements, which makes it possible to preserve horizontal polarization for a long time. Computer experiments study the dynamics of 10{sup 6}–10{sup 9} particles in a beam during 10{sup 9} turns in an accelerator (about 10{sup 12}–10{sup 15} integration steps for the equations of motion). For designing an optimal accelerator structure, a large number of computer experiments on polarized beam dynamics are required. The numerical core of the package is COSY Infinity, a program for modeling spin–orbit dynamics.

  15. Mechanical design upgrade of the APS storage ring rf cavity tuner

    SciTech Connect (OSTI)

    Jones, J.; Bromberek, D.; Kang, Y.

    1997-08-01

    The Advanced Photon Source (APS) storage ring (SR) rf system employs four banks of four spherical, single-cell resonant cavities. Each cavity is tuned by varying the cavity volume through insertion/retraction of a copper piston located at the circumference of the cavity and oriented perpendicular to the accelerator beam. During the commissioning of the APS SR, the tuners and cavity tuner ports were prone to extensive arcing and overheating. The existing tuners were modified to eliminate the problems, and two new, redesigned tuners were installed. In both cases marked improvements were obtained in the tuner mechanical performance. As measured by tuner piston and flange surface temperatures, tuner heating has been reduced by a factor of five in the new version. Redesign considerations discussed include tuner piston-to-housing alignment, tuner piston and housing materials and cooling configurations, and tuner piston sliding electrical contacts. The tuner redesign is also distinguished by a modular, more maintainable assembly.

  16. Prediction of enhanced solvent-induced enantioselectivity for a ring opening with a bifurcating reaction path

    SciTech Connect (OSTI)

    Carpenter, Barry K.; Harvey, Jeremy N.; Glowacki, David R.

    2014-12-11

    Classical molecular dynamics simulations are reported for the deazetisation and ring opening of meso-2,3-difluoro-2,3-dimethyldiazocyclopropane in three solvents: CHCl3, CHFClBr and CH3CH(OH)CF3 (TFIPA). In this study, the achiral reactant leads to enantiomeric allene products, and the question addressed in the study is whether either of the chiral, enantiomerically pure solvents can induce significant enantiomeric excess in the products. The direct dynamics calculations use an empirical valence bond potential for the solute, with empirical parameters optimised against M06-2X/cc-pVTZ density functional results. The results reveal that the exothermic N2 loss and ring opening promote transient strong solvent–solute interactions within the first ~100 fs of the reaction. Because of the bifurcating reaction path, these interactions occur at time when the “decision” about which enantiomer of the product to form has yet to be made (at least for many of the trajectories). Hence, it is possible in principle that the solvent could exert a larger-than-normal influence on the course of the reaction. In fact, the results reveal no such effect for CHFClBr but do predict that TFIPA should induce 15.2 ± 2.1% enantiomeric excess. This is roughly an order of magnitude larger than solvent-induced enantiomeric excesses found experimentally in reactions where the conversion of reactant(s) to enantiomeric products occur over separate transition states.

  17. Prediction of enhanced solvent-induced enantioselectivity for a ring opening with a bifurcating reaction path

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

    Carpenter, Barry K.; Harvey, Jeremy N.; Glowacki, David R.

    2014-12-11

    Classical molecular dynamics simulations are reported for the deazetisation and ring opening of meso-2,3-difluoro-2,3-dimethyldiazocyclopropane in three solvents: CHCl3, CHFClBr and CH3CH(OH)CF3 (TFIPA). In this study, the achiral reactant leads to enantiomeric allene products, and the question addressed in the study is whether either of the chiral, enantiomerically pure solvents can induce significant enantiomeric excess in the products. The direct dynamics calculations use an empirical valence bond potential for the solute, with empirical parameters optimised against M06-2X/cc-pVTZ density functional results. The results reveal that the exothermic N2 loss and ring opening promote transient strong solvent–solute interactions within the first ~100 fsmore » of the reaction. Because of the bifurcating reaction path, these interactions occur at time when the “decision” about which enantiomer of the product to form has yet to be made (at least for many of the trajectories). Hence, it is possible in principle that the solvent could exert a larger-than-normal influence on the course of the reaction. In fact, the results reveal no such effect for CHFClBr but do predict that TFIPA should induce 15.2 ± 2.1% enantiomeric excess. This is roughly an order of magnitude larger than solvent-induced enantiomeric excesses found experimentally in reactions where the conversion of reactant(s) to enantiomeric products occur over separate transition states.« less

  18. Cervical brachytherapy utilizing ring applicator: Comparison of standard and conformal loading

    SciTech Connect (OSTI)

    Brooks, Susan; Bownes, Peter; Lowe, Gerry; Bryant, Lynda; Hoskin, Peter J. . E-mail: peterhoskin@nhs.net

    2005-11-01

    Purpose: Afterloading high-dose-rate brachytherapy (HDR) treatment of cervical cancer with cross-sectional imaging and three-dimensional (3D) reconstruction offers opportunities for individualized conformal treatment planning rather than fixed point-A dosimetry. Methods and Materials: Between June 2003 and September 2004, 15 patients with FIGO Stage 1B-4A cervical carcinoma, median age 56 years, were treated with radical external-beam radiotherapy to pelvis, including paraortic nodes if positive on staging investigations. Fourteen patients received concurrent cisplatin chemotherapy. All patients received HDR brachytherapy administered by intrauterine tube and ring applicator. Clinical target volume (CTV) and organs at risk (OAR)-rectum, bladder, and small bowel-were outlined from postinsertion CT planning scans. Planning target volume (PTV) was derived by use of 2-mm to 3-mm 3D expansion. A standard plan was produced that delivered 6 Gy to point A, and a second plan delivered 6 Gy to PTV. Constraints were defined for the OAR: bladder, 6 Gy; rectum, 5 Gy; and small bowel, 5 Gy. Dosimetric comparison was performed by use of the Baltas conformal index (COIN). Results: Mean COIN values were 0.39 for conformal plans and 0.33 for standard plans (p = 0.001); mean D95 values were 4.79 Gy and 4.50 Gy, respectively. Conclusion: The majority of patients achieved a plan closer to ideal for coverage of PTV, with minimization of radiation received by normal tissues for conformal loading measured by COIN compared with fixed point-A prescription that used the cervical ring applicator.

  19. The trace of the CNO cycle in the ring nebula NGC 6888

    SciTech Connect (OSTI)

    Mesa-Delgado, A.; Esteban, C.; García-Rojas, J.; Reyes-Pérez, J.; Morisset, C.; Bresolin, F.

    2014-04-20

    We present new results on the chemical composition of the Galactic ring nebula NGC 6888 surrounding the WN6(h) star WR136. The data are based on deep spectroscopical observations taken with the High Dispersion Spectrograph at the 8.2 m Subaru Telescope. The spectra cover the optical range from 3700 to 7400 Å. The effect of the CNO cycle is well-identified in the abundances of He, N, and O, while elements not involved in the synthesis such as Ar, S, and Fe present values consistent with the solar vicinity and the ambient gas. The major achievement of this work is the first detection of the faint C II λ4267 recombination line in a Wolf-Rayet nebula. This allows us to estimate the C abundance in NGC 6888 and therefore investigate for the first time the trace of the CNO cycle in a ring nebula around a Wolf-Rayet star. Although the detection of the C II line has a low signal-to-noise ratio, the C abundance seems to be higher than the predictions of recent stellar evolution models of massive stars. The Ne abundance also shows a puzzling pattern with an abundance of about 0.5 dex lower than the solar vicinity, which may be related to the action of the NeNa cycle. Attending to the constraints imposed by the dynamical timescale and the He/H and N/O ratios of the nebula, the comparison with stellar evolution models indicates that the initial mass of the stellar progenitor of NGC 6888 is between 25 M {sub ☉} and 40 M {sub ☉}.

  20. Can the ring polymer molecular dynamics method be interpreted as real time quantum dynamics?

    SciTech Connect (OSTI)

    Jang, Seogjoo; Sinitskiy, Anton V.; Voth, Gregory A.

    2014-04-21

    The ring polymer molecular dynamics (RPMD) method has gained popularity in recent years as a simple approximation for calculating real time quantum correlation functions in condensed media. However, the extent to which RPMD captures real dynamical quantum effects and why it fails under certain situations have not been clearly understood. Addressing this issue has been difficult in the absence of a genuine justification for the RPMD algorithm starting from the quantum Liouville equation. To this end, a new and exact path integral formalism for the calculation of real time quantum correlation functions is presented in this work, which can serve as a rigorous foundation for the analysis of the RPMD method as well as providing an alternative derivation of the well established centroid molecular dynamics method. The new formalism utilizes the cyclic symmetry of the imaginary time path integral in the most general sense and enables the expression of Kubo-transformed quantum time correlation functions as that of physical observables pre-averaged over the imaginary time path. Upon filtering with a centroid constraint function, the formulation results in the centroid dynamics formalism. Upon filtering with the position representation of the imaginary time path integral, we obtain an exact quantum dynamics formalism involving the same variables as the RPMD method. The analysis of the RPMD approximation based on this approach clarifies that an explicit quantum dynamical justification does not exist for the use of the ring polymer harmonic potential term (imaginary time kinetic energy) as implemented in the RPMD method. It is analyzed why this can cause substantial errors in nonlinear correlation functions of harmonic oscillators. Such errors can be significant for general correlation functions of anharmonic systems. We also demonstrate that the short time accuracy of the exact path integral limit of RPMD is of lower order than those for finite discretization of path. The

  1. Comparison of effectiveness of sub-slab ventilation systems for indoor radon mitigation: A numerical study; Comparaison a l`aide d`un outil numerique de l`efficacite des systemes de ventilation active du sol limitant la penetration du radon dans l`habitat

    SciTech Connect (OSTI)

    Bonnefous, Y.C. |; Gadgil, A.J.; Allard, F.

    1992-04-01

    The functioning of an active sub-slab ventilation system (SVS) has been studied successfully with the help of a previously evaluated numerical model. The parameters explored are the permeability of the sub-slab and the gravel placed beneath it, the amplitude of applied pressure at the installation point of the system and the functioning method: depressurization or pressurization. The mechanisms contributing to the success of the two systems are identified. This numerical study shows that the presence of a layer of gravel beneath the sub-slab considerably improves the performance of the SVS. Considered separately from the extremely permeable sub-slabs, the depressurization systems perform better than the pressurization systems. 17 refs. [Francais] Le fonctionnement des Systemes de Ventilation active du Sol (SVS) a ete etudie a l`aide d`un outil numerique precedemment evalue avec succes. Les parametres explores sont les permeabilites du sol et du gravier place sous plancher bas, l`amplitude de la pression appliquee au point d`installation du systeme, et le mode de fonctionnement: Depressurisation ou Pressurisation. Les mecanismes contribuant au succes des deux systemes sont identifies. Cette etude numerique montre que la presence d`une couche de gravier sous plancher bas ameliore de facon considerable les performances des SVS. Mis a part le cas des sols extremement permeables, les systemes de Depressurisation ont de meilleures performances que les systemes de Pressurisation. 17 refs.

  2. The Concentration and Distribution of Depleted Uranium (DU) and Beryllium (Be) in Soil and Air on Illeginni Island at Kwajalein Atoll

    SciTech Connect (OSTI)

    Robison, W L; Hamilton, T F; Martinelli, R E; Gouveia, F J; Lindman, T R; Yakuma, S C

    2006-04-27

    Re-entry vehicles on missiles launched at Vandenberg Air Force base in California re-enter at the Western Test Range, the Regan Test Site (RTS) at Kwajalein Atoll. An environmental Assessment (EA) was written at the beginning of the program to assess potential impact of Depleted Uranium (DU) and Beryllium (Be), the major RV materials of interest from a health and environmental perspective. The chemical and structural form of DU and Be in RVs is such that they are insoluble in soil water and sea water. Consequently, residual concentrations of DU and Be observed in soil on the island are not expected to be toxic to plant life because there is essentially no soil to plant uptake. Similarly, due to their insolubility in sea water there is no uptake of either element by marine biota including fish, mollusks, shellfish and sea mammals. No increase in either element has been observed in sea life around Illeginni Island where deposition of DU and Be has occurred. The critical terrestrial exposure pathway for U and Be is inhalation. Concentration of both elements in air over the test period (1989 to 2006) is lower by a factor of 10,000 than the most restrictive U.S. guideline for the general public. Uranium concentrations in air are also lower by factors of 10 to 100 than concentrations of U in air in the U.S. measured by the EPA (Keith et al., 1999). U and Be concentrations in air downwind of deposition areas on Illeginni Island are essentially indistinguishable from natural background concentrations of U in air at the atolls. Thus, there are no health related issues associated with people using the island.

  3. The E1 copper binding domain of full-length amyloid precursor protein mitigates copper-induced growth inhibition in brain metastatic prostate cancer DU145 cells

    SciTech Connect (OSTI)

    Gough, Mallory Blanthorn-Hazell, Sophee Delury, Craig Parkin, Edward

    2014-10-31

    Highlights: • Copper levels are elevated in the tumour microenvironment. • APP mitigates copper-induced growth inhibition of DU145 prostate cancer (PCa) cells. • The APP intracellular domain is a prerequisite; soluble forms have no effect. • The E1 CuBD of APP is also a prerequisite. • APP copper binding potentially mitigates copper-induced PCa cell growth inhibition. - Abstract: Copper plays an important role in the aetiology and growth of tumours and levels of the metal are increased in the serum and tumour tissue of patients affected by a range of cancers including prostate cancer (PCa). The molecular mechanisms that enable cancer cells to proliferate in the presence of elevated copper levels are, therefore, of key importance in our understanding of tumour growth progression. In the current study, we have examined the role played by the amyloid precursor protein (APP) in mitigating copper-induced growth inhibition of the PCa cell line, DU145. A range of APP molecular constructs were stably over-expressed in DU145 cells and their effects on cell proliferation in the presence of copper were monitored. Our results show that endogenous APP expression was induced by sub-toxic copper concentrations in DU145 cells and over-expression of the wild-type protein was able to mitigate copper-induced growth inhibition via a mechanism involving the cytosolic and E1 copper binding domains of the full-length protein. APP likely represents one of a range of copper binding proteins that PCa cells employ in order to ensure efficient proliferation despite elevated concentrations of the metal within the tumour microenvironment. Targeting the expression of such proteins may contribute to therapeutic strategies for the treatment of cancers.

  4. Parametric study of the damage ring pattern in fused silica induced by multiple longitudinal modes laser pulses

    SciTech Connect (OSTI)

    Chambonneau, M. Grua, P.; Rullier, J.-L.; Lamaignère, L.; Natoli, J.-Y.

    2015-03-14

    With the use of multiple longitudinal modes nanosecond laser pulses at 1064 nm, laser damage sites at the exit surface of fused silica clearly and systematically exhibit ring patterns. It has been shown in our previous works that the apparent chronology of rings was closely related to the temporal shape of the laser pulses. This particular correspondence had suggested an explanation of the ring morphology formation based on the displacement of an ionization front in the surrounding air. To provide a former basis for this hypothesis and deeper understanding of ring pattern formation, additional experiments have been performed. First, the impact of fluence has been investigated, revealing that a wide variety of damage sites are produced within a very narrow fluence range; this fact involves the chronology of appearance of a surface plasma during the laser pulse. The sizes of the damage sites are proportional to the fluence of their expansion occurring between the beginning of the plasma and the end of the laser pulse. Second, specific experiments have been carried out at different angles of incidence, resulting in egg-shaped patterns rather than circular ones. This behavior can be explained by our previous hypothesis of creation of a plasma in air, its expansion being tightly conditioned by the illumination angle. This series of experiments, in which the angle of incidence is varied up to 80°, permits us to link quantitatively the working hypothesis of ionization front propagation with theoretical hydrodynamics modeling.

  5. Method and apparatus for elemental and isotope measurements and diagnostics-microwave induced plasma-cavity ring-down spectroscopy

    DOE Patents [OSTI]

    Wang, Chuji; Winstead, Christopher; Duan, Yixiang

    2006-05-30

    Provided is a novel system for conducting elemental measurements using cavity ring-down spectroscopy (CRDS). The present invention provides sensitivity thousands of times improved over conventional devices and does so with the advantages of low power, low plasma flow rate, and the ability being sustained with various gases.

  6. Compounds having aromatic rings and side-chain amide-functionality and a method for transporting monovalent anions across biological membranes using the same

    DOE Patents [OSTI]

    Davis, Jeffery T.; Sidorov, Vladimir; Kotch, Frank W.

    2008-04-08

    A compound containing at least two aromatic rings covalently bonded together, with each aromatic ring containing at least one oxyacetamide-based side chain, the compound being capable of forming a chloride ion channel across a lipid bilayer, and transporting chloride ion across the lipid bilayer.

  7. CSR behavior and aging model for the Viton© Fluorelastomer O-rings in the 9975 shipping package

    SciTech Connect (OSTI)

    Mcwilliams, A. J.; Daugherty, W. L.; Skidmore, T. E.

    2015-12-01

    The 9975 Type B shipping package is used within the DOE complex for shipping special nuclear materials. This package is re-certified annually in accordance with Safety Analysis Report for Packaging (SARP) requirements. The package is also used at the Savannah River Site as part of the long-term storage configuration of special nuclear materials. As such, the packages do not undergo annual recertification during storage, with uncertainty as to how long some of the package components will meet their functional requirements in the storage environment. The packages are currently approved for up to 15 years storage, and work continues to provide a technical basis to extend that period. This report describes efforts by the Savannah River National Laboratory (SRNL) to extend the service life estimate of Viton® GLT and GLT-S fluoroelastomer O-rings used in the 9975 shipping package. O-rings of both GLT and GLT-S compositions are undergoing accelerated aging at elevated temperature, and are periodically tested for compression stress relaxation (CSR) behavior. The CSR behavior of O-rings was evaluated at temperatures from 175 to 400 °F. These collective data were used to develop predictive models for extrapolation of CSR behavior to relevant service temperatures (< 156 °F). The predictive model developed from the CSR data conservatively indicates a service life of approximately 37 years for Viton GLT O-rings at the maximum effective service temperature of 156 °F. The estimated service life for Viton GLT-S O-rings is significantly longer.

  8. STATUS REPORT FOR AGING STUDIES OF EPDM O-RING MATERIAL FOR THE H1616 SHIPPING PACKAGE

    SciTech Connect (OSTI)

    Stefek, T.; Daugherty, W.; Skidmore, E.

    2012-08-31

    This is an interim status report for tasks carried out per Task Technical Plan SRNL-STI-2011-00506. A series of tasks/experiments are being performed at the Savannah River National Laboratory to monitor the aging performance of ethylene propylene diene monomer (EPDM) Orings used in the H1616 shipping package. The data will support the technical basis to extend the annual maintenance of the EPDM O-rings in the H1616 shipping package and to predict the life of the seals at bounding service conditions. Current expectations are that the O-rings will maintain a seal at bounding normal temperatures in service (152 F) for at least 12 months. The baseline aging data review suggests that the EPDM O-rings are likely to retain significant mechanical properties and sealing force at bounding service temperatures to provide a service life of at least 2 years. At lower, more realistic temperatures, longer service life is likely. Parallel compression stress relaxation and vessel leak test efforts are in progress to further validate this assessment and quantify a more realistic service life prediction. The H1616 shipping package O-rings were evaluated for baseline property data as part of this test program. This was done to provide a basis for comparison of changes in material properties and performance parameters as a function of aging. This initial characterization was limited to physical and mechanical properties, namely hardness, thickness and tensile strength. These properties appear to be consistent with O-ring specifications. Three H1616-1 Containment Vessels were placed in test conditions and are aging at temperatures ranging from 160 to 300 F. The vessels were Helium leak-tested initially and have been tested at periodic intervals after cooling to room temperature to determine if they meet the criterion of leaktightness defined in ANSI standard N14.5-97 (< 1E-07 std cc air/sec at room temperature). To date, no leak test failures have occurred. The cumulative time at

  9. Trapping two types of particles using a double-ring-shaped radially polarized beam

    SciTech Connect (OSTI)

    Zhang Yaoju; Ding Biaofeng; Suyama, Taikei

    2010-02-15

    An optical-trap method based on the illumination of a double-ring-shaped radially polarized beam (R-TEM{sub 11}*) is proposed. The numerical results based on the vector diffraction theory show that a highly focused R-TEM{sub 11}* beam not only can produce a bright spot but also can form an optical cage in the focal region by changing the truncation parameter {beta}, defined as the ratio of the radius of the aperture to the waist of the beam. The radiation forces acting on Rayleigh particles are calculated by using the Rayleigh scattering theory. The bright spot generated by the R-TEM{sub 11}* beam with a {beta} value close to 2 can three-dimensionally trap a particle with a refractive index larger than that of the ambient. An optical cage or three-dimensional dark spot generated by the R-TEM{sub 11}* beam with a {beta} value close to 1.3 can three-dimensionally trap a particle with refractive index smaller than that of the ambient. Because the adjustment of the truncation parameter can be actualized by simply changing the radius of a circular aperture inserted in the front of the lens, only one optical-trap system in the present method can be used to three-dimensionally trap two types of particles with different refractive indices.

  10. Study of photonmagnon coupling in a YIG-film split-ring resonant system

    SciTech Connect (OSTI)

    Bhoi, B.; Aiyar, R.; Cliff, T.; Maksymov, I. S.; Kostylev, M.; Venkataramani, N.; Prasad, S.; Stamps, R. L.

    2014-12-28

    By using the stripline Microwave VectorNetwork Analyser Ferromagnetic Resonance and Time Domain spectroscopy techniques, we study a strong coupling regime of magnons to microwave photons in the planar geometry of a lithographically formed split-ring resonator (SRR) loaded by a single-crystal epitaxial yttriumirongarnet (YIG) film. Strong anti-crossing of the photon modes of SRR and of the magnon modes of the YIG film is observed in the applied-magnetic-field resolved measurements. The coupling strength extracted from the experimental data reaches 9% at 3?GHz. Theoretically, we propose an equivalent circuit model of the SRR loaded by a magnetic film. This model follows from the results of our numerical simulations of the microwave field structure of the SRR and of the magnetisation dynamics in the YIG film driven by the microwave currents in the SRR. The results obtained with the equivalent-circuit model are in good agreement with the experiment. This model provides a simple physical explanation of the process of mode anti-crossing. Our findings are important for future applications in microwave quantum photonic devices as well as in nonlinear and magnetically tuneable metamaterials exploiting the strong coupling of magnons to microwave photons.

  11. Finite-size effects in a metallic multichannel ring with Kondo impurity: Persistent currents and magnetoresistance

    SciTech Connect (OSTI)

    Zvyagin, A.A.; Schlottmann, P.

    1996-12-01

    We consider a spin-1/2 impurity interacting with conduction electrons in two different orbital channels via an isotropic spin exchange. The exchange is the same for both channels, but a crystalline field breaks the symmetry between the orbital channels. This corresponds to a splitting of the conduction electron {Gamma}{sub 8} into two doublets in the quadrupolar Kondo effect, or to the electron-assisted tunneling of an atom in a double-well potential in an external magnetic field. Another possible realization could be a quantum dot coupled to two equal rings of the same length subject to an electrostatic potential difference. We consider the Bethe ansatz equations for this model and derive the tower structure of the finite-size corrections to the ground-state energy. These results are used to discuss the Aharonov-Bohm-Casher interference pattern in the persistent charge and spin currents, and the magnetoresistivity due to the scattering of electrons off the impurity. {copyright} {ital 1996 The American Physical Society.}

  12. Resonance hybridization and near field properties of strongly coupled plasmonic ring dimer-rod nanosystem

    SciTech Connect (OSTI)

    Koya, Alemayehu Nana; Ji, Boyu; Hao, Zuoqiang; Lin, Jingquan

    2015-09-21

    Combined effects of polarization, split gap, and rod width on the resonance hybridization and near field properties of strongly coupled gold dimer-rod nanosystem are comparatively investigated in the light of the constituent nanostructures. By aligning polarization of the incident light parallel to the long axis of the nanorod, introducing small split gaps to the dimer walls, and varying width of the nanorod, we have simultaneously achieved resonance mode coupling, huge near field enhancement, and prolonged plasmon lifetime. As a result of strong coupling between the nanostructures and due to an intense confinement of near fields at the split and dimer-rod gaps, the extinction spectrum of the coupled nanosystem shows an increase in intensity and blueshift in wavelength. Consequently, the near field lifespan of the split-nanosystem is prolonged in contrast to the constituent nanostructures and unsplit-nanosystem. On the other hand, for polarization of the light perpendicular to the long axis of the nanorod, the effect of split gap on the optical responses of the coupled nanosystem is found to be insignificant compared to the parallel polarization. These findings and such geometries suggest that coupling an array of metallic split-ring dimer with long nanorod can resolve the huge radiative loss problem of plasmonic waveguide. In addition, the Fano-like resonances and immense near field enhancements at the split and dimer-rod gaps imply the potentials of the nanosystem for practical applications in localized surface plasmon resonance spectroscopy and sensing.

  13. A Performance Comparison of Tree and Ring Topologies in Distributed System

    SciTech Connect (OSTI)

    Min Huang

    2005-12-19

    A distributed system is a collection of computers that are connected via a communication network. Distributed systems have become commonplace due to the wide availability of low-cost, high performance computers and network devices. However, the management infrastructure often does not scale well when distributed systems get very large. Some of the considerations in building a distributed system are the choice of the network topology and the method used to construct the distributed system so as to optimize the scalability and reliability of the system, lower the cost of linking nodes together and minimize the message delay in transmission, and simplify system resource management. We have developed a new distributed management system that is able to handle the dynamic increase of system size, detect and recover the unexpected failure of system services, and manage system resources. The topologies used in the system are the tree-structured network and the ring-structured network. This thesis presents the research background, system components, design, implementation, experiment results and the conclusions of our work. The thesis is organized as follows: the research background is presented in chapter 1. Chapter 2 describes the system components, including the different node types and different connection types used in the system. In chapter 3, we describe the message types and message formats in the system. We discuss the system design and implementation in chapter 4. In chapter 5, we present the test environment and results, Finally, we conclude with a summary and describe our future work in chapter 6.

  14. Peculiarity of convergence of shock wave generated by underwater electrical explosion of ring-shaped wire

    SciTech Connect (OSTI)

    Shafer, D.; Toker, G. R.; Gurovich, V. Tz.; Gleizer, S.; Krasik, Ya. E.

    2013-05-15

    Nanosecond timescale underwater electrical wire explosions of ring-shaped Cu wires were investigated using a pulsed generator with a current amplitude up to 50 kA. It was shown that this type of wire explosion results in the generation of a toroidal shock wave (SW). Time- and space-resolved optical diagnostics were used to determine azimuthal uniformity of the shock wave front and its velocity. It was found that the shock wave preserves its circular front shape in the range of radii 50?m

  15. Hard x-ray tomographic studies of the destruction of an energetic electron ring

    SciTech Connect (OSTI)

    Wang, Y.; Gekelman, W.; Pribyl, P.

    2013-05-15

    A tomography system was designed and built at the Large Plasma Device to measure the spatial distribution of hard x-ray (100 KeV-3 MeV) emissivity. The x-rays were generated when a hot electron ring was significantly disrupted by a shear Alfven wave. The plasma is pulsed at 1 Hz (1 shot/s). A lead shielded scintillator detector with an acceptance angle defined by a lead pinhole is mounted on a rotary gimbal and used to detect the x-rays. The system measures one chord per plasma shot using only one detector. A data plane usually consists of several hundred chords. A novel Dot by Dot Reconstruction (DDR) method is introduced to calculate the emissivity profile from the line integrated data. In the experiments, there are often physical obstructions, which make measurements at certain angles impossible. The DDR method works well even in this situation. The method was tested with simulated data, and was found to be more effective than previously published methods for the specific geometry of this experiment. The reconstructed x-ray emissivity from experimental data by this method is shown.

  16. A long-lived relativistic electron storage ring embedded in Earth's Outer Van Allen belt

    SciTech Connect (OSTI)

    Baker, D. N.; Kanekal, S. G.; Hoxie, V. C.; Henderson, M. G.; Li, X.; Spence, H. E.; Elkington, S. R.; Friedel, R. H. W.; Goldstein, J.; Hudson, M. K.; Reeves, G. D.; Thorne, R. M.; Kletzing, C. A.; Claudepierre, S. G.

    2013-02-28

    Since their discovery over 50 years ago, the Earth’s Van Allen radiation belts are thought to consist of two distinct zones of trapped, highly energetic charged particles. The outer zone is comprised predominantly of mega-electron volt (MeV) electrons that wax and wane in intensity on time scales ranging from hours to days depending primarily on external forcing by the solar wind. Thus, the spatially separated inner zone is comprised of commingled high-energy electrons and very energetic positive ions (mostly protons), the latter being stable in intensity levels over years to decades. In situ energy-specific and temporally resolved spacecraft observations reveal an isolated third ring, or torus, of high-energy (E > 2 MeV) electrons that formed on 2 September 2012 and persisted largely unchanged in the geocentric radial range of 3.0 to ~3.5 Earth radii for over four weeks before being disrupted (and virtually annihilated) by a powerful interplanetary shock wave passage.

  17. SUPER-RESOLUTION ULTRASOUND TOMOGRAPHY: A PRELIMINARY STUDY WITH A RING ARRAY

    SciTech Connect (OSTI)

    HUANG, LIANJIE; SIMONETTI, FRANCESCO; DURIC, NEBOJSA; RAMA, OLSI

    2007-01-18

    Ultrasound tomography attempts to retrieve the structure of an objective by exploiting the interaction of acoustic waves with the object. A fundamental limit of ultrasound tomography is that features cannot be resolved if they are spaced less than {lambda}/2 apart, where {lambda} is wavelength of the probing wave, regardless of the degree of accuracy of the measurements. Therefore, since the attenuation of the probing wave with propagation distance increases as {lambda} decreases, resolution has to be traded against imaging depth. Recently, it has been shown that the {lambda}/2 limit is a consequence of the Born approximation (implicit in the imaging algorithms currently employed) which neglects the distortion of the probing wavefield as it travels through the medium to be imaged. On the other hand, such a distortion, which is due to the multiple scattering phenomenon, can encode unlimited resolution in the radiating component of the scattered field. Previously, a resolution better than {lambda}/3 has been reported in these proceedings [F. Simonetti, pp. 126 (2006)] in the case of elastic wave probing. In this paper, they demonstrate experimentally a resolution better than {lambda}/4 for objects immersed in a water bth probed by means of a ring array which excites and detects pressure waves in a full view configuration.

  18. IMPLEMENTATION OF A DC BUMP AT THE STORAGE RING INJECTION STRAIGHT SECTION

    SciTech Connect (OSTI)

    Wang, G.M.; Shaftan, T.; Kramer, S.K.; Fliller, R.; Guo, W.; Heese, R.; Yu, L.H.; Parker, B.; Willeke, F.J.

    2011-03-28

    The NSLS II beam injection works with a DC septum, a pulsed septum and four fast kicker magnets. The kicker power supplies each produce a two revolution period pulsed field, 5.2 {micro}s half sine waveform, using {approx}5kA drive voltage. The corresponding close orbit bump amplitude is {approx}15mm. It is desired that the bump is transparent to the users for top-off injection. However, high voltage and short pulse power supplies have challenges to maintain pulse-to-pulse stability and magnet-to-magnet reproducibility. To minimize these issues, we propose implementing a DC local bump on top of the fast bump to reduce the fast kicker strength by a factor of 2/3. This bump uses two storage ring corrector magnets plus one additional magnet at the septum to create a local bump. Additionally, these magnets could provide a DC bump to simulate the septum position effects on the store beam lifetime. This paper presents the detail design of this DC injection bump and related beam dynamics.

  19. FCC046: A CANDIDATE GASEOUS POLAR RING DWARF ELLIPTICAL GALAXY IN THE FORNAX CLUSTER

    SciTech Connect (OSTI)

    De Rijcke, S.; Buyle, P.; Koleva, M.

    2013-06-20

    FCC046 is a Fornax Cluster dwarf elliptical galaxy. Optical observations have shown that this galaxy, besides an old and metal-poor stellar population, also contains a very young centrally concentrated population and is actively forming stars, albeit at a very low level. Here, we report on 21 cm observations of FCC046 with the Australia Telescope Compact Array which we conducted in the course of a small survey of Fornax Cluster early-type dwarf galaxies. We have discovered a {approx}10{sup 7} M{sub Sun} H I cloud surrounding FCC046. We show that the presence of this significant gas reservoir offers a concise explanation for this galaxy's optical morphological and kinematical properties. Surprisingly, the H I gas, as evidenced by its morphology and its rotational motion around the galaxy's optical major axis, is kinematically decoupled from the galaxy's stellar body. This is the first time such a ring of gaseous material in minor-axis rotation is discovered around a dwarf galaxy.

  20. A long-lived relativistic electron storage ring embedded in Earth's Outer Van Allen belt

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

    Baker, D. N.; Kanekal, S. G.; Hoxie, V. C.; Henderson, M. G.; Li, X.; Spence, H. E.; Elkington, S. R.; Friedel, R. H. W.; Goldstein, J.; Hudson, M. K.; et al

    2013-02-28

    Since their discovery over 50 years ago, the Earth’s Van Allen radiation belts are thought to consist of two distinct zones of trapped, highly energetic charged particles. The outer zone is comprised predominantly of mega-electron volt (MeV) electrons that wax and wane in intensity on time scales ranging from hours to days depending primarily on external forcing by the solar wind. Thus, the spatially separated inner zone is comprised of commingled high-energy electrons and very energetic positive ions (mostly protons), the latter being stable in intensity levels over years to decades. In situ energy-specific and temporally resolved spacecraft observations revealmore » an isolated third ring, or torus, of high-energy (E > 2 MeV) electrons that formed on 2 September 2012 and persisted largely unchanged in the geocentric radial range of 3.0 to ~3.5 Earth radii for over four weeks before being disrupted (and virtually annihilated) by a powerful interplanetary shock wave passage.« less

  1. Quantum nonlinear resonance and quantum chaos in Aharonov-Bohm oscillations in mesoscopic semiconductor rings

    SciTech Connect (OSTI)

    Berman, G.P. [Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Bulgakov, E.N. [Kirensky Institute of Physics, 660036, Krasnoyarsk (Russia)] [Kirensky Institute of Physics, 660036, Krasnoyarsk (Russia); Campbell, D.K. [Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080 (United States)] [Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080 (United States); Krive, I.V. [Institute for Low Temperature Physics and Engineering, Ukrainian Academy of Sciences, 310164, Kharkov (Ukraine)] [Institute for Low Temperature Physics and Engineering, Ukrainian Academy of Sciences, 310164, Kharkov (Ukraine)

    1997-10-01

    We consider Aharonov-Bohm oscillations in a mesoscopic semiconductor ring threaded by both a constant magnetic flux and a time-dependent, resonant magnetic field with one or two frequencies. Working in the ballistic regime, we establish that the theory of {open_quotes}quantum nonlinear resonance{close_quotes} applies, and thus that this system represents a possible solid-state realization of {open_quotes}quantum nonlinear resonance{close_quotes} and {open_quotes}quantum chaos.{close_quotes} In particular, we investigate the behavior of the time-averaged electron energy at zero temperature in the regimes of (i) an isolated quantum nonlinear resonance and (ii) the transition to quantum chaos, when two quantum nonlinear resonances overlap. The time-averaged energy exhibits sharp resonant behavior as a function of the applied constant magnetic flux, and has a staircase dependence on the amplitude of the external time-dependent field. In the chaotic regime, the resonant behavior exhibits complex structure as a function of flux and frequency. We compare and contrast the quantum chaos expected in these mesoscopic {open_quotes}solid-state atoms{close_quotes} with that observed in Rydberg atoms in microwave fields, and discuss the prospects for experimental observation of the effects we predict. {copyright} {ital 1997} {ital The American Physical Society}

  2. METALLIZATION OF CERAMIC VACUUM CHAMBERS FOR SNS RING INJECTION KICKER MAGNETS.

    SciTech Connect (OSTI)

    HE,P.; HSEUH,H.C.; TODD,R.J.

    2002-04-22

    Ceramic chambers will be used in the pulsed kicker magnets for the injection of H{sup -} into the US Spallation Neutron Source (SNS) accumulator ring. There are two reasons for using ceramic chambers in kickers: (1) to avoid shielding of a fast-changing external magnetic field by metallic chamber walls; and (2) to reduce heating due to eddy currents. The inner surfaces of the ceramic chambers will be coated with a conductive layer, possibly titanium (Ti) or copper with a titanium nitride (TiN) overlayer, to reduce the beam coupling impedance and provide passage for beam image current. This paper describes the development of sputtering method for the 0.83m long 16cm inner diameter ceramic chambers. Coatings of Ti, Cu and TiN with thicknesses up to 10 {micro}m were produced by means of DC magnetron sputtering. The difficulty of coating insulators was overcome with the introduction of an anode screen. Films with good adhesion, uniform longitudinal thickness, and conductivity were produced.

  3. Spin power and efficiency in an Aharnov-Bohm ring with an embedded magnetic impurity quantum dot

    SciTech Connect (OSTI)

    Yang, Xi; Guo, Yong; Zheng, Jun; Chi, Feng

    2015-05-11

    Spin thermoelectric effects in an Aharnov-Bohm ring with a magnetic impurity quantum dot (QD) are theoretically investigated by using the nonequilibrium Green's function method. It is found that due to the exchange coupling between the impurity and the electrons in QD, spin output power, and efficiency can be significant and be further modulated by the gate voltage. The spin thermoelectric effect can be modulated effectively by adjusting the Rashba spin-orbit interaction (RSOI) and the magnetic flux. The spin power and efficiency show zigzag oscillations, and thus spin thermoelectric effect can be switched by adjusting the magnetic flux phase factor and RSOI ones. In addition, the spin efficiency can be significantly enhanced by the coexistence of the RSOI and the magnetic flux, and the maximal value of normalized spin efficiency ?{sub max}/?{sub C}?=?0.35 is obtained. Our results show that such a QD ring device may be used as a manipulative spin thermoelectric generator.

  4. Recent Electron-Cloud Simulation Results for the Main Damping Rings of the NLC and the TESLA Linear Colliders

    SciTech Connect (OSTI)

    Pivi, Mauro T F

    2003-05-19

    In the beam pipe of the Main Damping Ring (MDR) of the Next Linear Collider (NLC), ionization of residual gases and secondary emission give rise to an electron-cloud which stabilizes to equilibrium after few bunch trains. In this paper, we present recent computer simulation results for the main features of the electron cloud at the NLC and preliminary simulation results for the TESLA main damping rings, obtained with the code POSINST that has been developed at LBNL, and lately in collaboration with SLAC, over the past 7 years. Possible remedies to mitigate the effect are also discussed. We have recently included the possibility to simulate different magnetic field configurations in our code including solenoid, quadrupole, sextupole and wiggler.

  5. Kondo Resonance in a Mesoscopic Ring Coupled to a Quantum Dot: Exact Results for the Aharonov-Bohm-Casher Effects

    SciTech Connect (OSTI)

    Eckle, H.-P.; Johannesson, H.; Stafford, C. A.

    2001-07-02

    We study the persistent currents induced by both the Aharonov-Bohm and Aharonov-Casher effects in a one-dimensional mesoscopic ring coupled to a sidebranch quantum dot at Kondo resonance. For privileged values of the Aharonov-Bohm-Casher fluxes, the problem can be mapped onto an integrable model, exactly solvable by a Bethe ansatz. In the case of a pure magnetic Aharonov-Bohm flux, we find that the presence of the quantum dot has no effect on the persistent current. In contrast, the Kondo resonance interferes with the spin-dependent Aharonov-Casher effect to induce a current which, in the strong-coupling limit, is independent of the number of electrons in the ring.

  6. Relativistic klystron driven compact high gradient accelerator as an injector to an X-ray synchrotron radiation ring

    DOE Patents [OSTI]

    Yu, David U. L.

    1990-01-01

    A compact high gradient accelerator driven by a relativistic klystron is utilized to inject high energy electrons into an X-ray synchrotron radiation ring. The high gradients provided by the relativistic klystron enables accelerator structure to be much shorter (typically 3 meters) than conventional injectors. This in turn enables manufacturers which utilize high energy, high intensity X-rays to produce various devices, such as computer chips, to do so on a cost effective basis.

  7. Polarimetry with the Gemini Planet Imager: methods, performance at first light, and the circumstellar ring around HR 4796A

    SciTech Connect (OSTI)

    Perrin, Marshall D.; Duchene, Gaspard; Millar-Blanchaer, Max; Fitzgerald, Michael P.; Graham, James R.; Wiktorowicz, Sloane J.; Kalas, Paul G.; Macintosh, Bruce; Bauman, Brian; Cardwell, Andrew; Chilcote, Jeffrey; De Rosa, Robert J.; Dillon, Daren; Doyon, René; Dunn, Jennifer; Erikson, Darren; Gavel, Donald; Goodsell, Stephen; Hartung, Markus; Hibon, Pascale; Ingraham, Patrick; Kerley, Daniel; Konapacky, Quinn; Larkin, James E.; Maire, Jérôme; Marchis, Franck; Marois, Christian; Mittal, Tushar; Morzinski, Katie M.; Oppenheimer, B. R.; Palmer, David W.; Patience, Jennifer; Poyneer, Lisa; Pueyo, Laurent; Rantakyrö, Fredrik T.; Sadakuni, Naru; Saddlemyer, Leslie; Savransky, Dmitry; Soummer, Rémi; Sivaramakrishnan, Anand; Song, Inseok; Thomas, Sandrine; Wallace, J. Kent; Wang, Jason J.; Wolff, Schuyler G.

    2015-01-28

    We present the first results from the polarimetry mode of the Gemini Planet Imager (GPI), which uses a new integral field polarimetry architecture to provide high contrast linear polarimetry with minimal systematic biases between the orthogonal polarizations. We describe the design, data reduction methods, and performance of polarimetry with GPI. Point spread function subtraction via di erential polarimetry suppresses unpolarized starlight by a factor of over 100, and provides sensitivity to circumstellar dust reaching the photon noise limit for these observations. In the case of the circumstellar disk around HR 4796A, GPI's advanced adaptive optics system reveals the disk clearly even prior to PSF subtraction. In polarized light, the disk is seen all the way in to its semi-minor axis for the first time. The disk exhibits surprisingly strong asymmetry in polarized intensity, with the west side ≳ 9 times brighter than the east side despite the fact that the east side is slightly brighter in total intensity. Based on a synthesis of the total and polarized intensities, we now believe that the west side is closer to us, contrary to most prior interpretations. Forward scattering by relatively large silicate dust particles leads to the strong polarized intensity on the west side, and the ring must be slightly optically thick in order to explain the lower brightness in total intensity there. These findings suggest that the ring is geometrically narrow and dynamically cold, perhaps shepherded by larger bodies in the same manner as Saturn's F ring.

  8. Polarimetry with the Gemini Planet Imager. Methods, performance at first light, and the circumstellar ring around HR 4796A

    SciTech Connect (OSTI)

    Perrin, Marshall D.; Duchene, Gaspard; Millar-Blanchaer, Max; Fitzgerald, Michael P.; Graham, James R.; Wiktorowicz, Sloane J.; Kalas, Paul G.; Macintosh, Bruce; Bauman, Brian; Cardwell, Andrew; Chilcote, Jeffrey; De Rosa, Robert J.; Dillon, Daren; Doyon, René; Dunn, Jennifer; Erikson, Darren; Gavel, Donald; Goodsell, Stephen; Hartung, Markus; Hibon, Pascale; Ingraham, Patrick; Kerley, Daniel; Konapacky, Quinn; Larkin, James E.; Maire, Jérôme; Marchis, Franck; Marois, Christian; Mittal, Tushar; Morzinski, Katie M.; Oppenheimer, B. R.; Palmer, David W.; Patience, Jennifer; Poyneer, Lisa; Pueyo, Laurent; Rantakyrö, Fredrik T.; Sadakuni, Naru; Saddlemyer, Leslie; Savransky, Dmitry; Soummer, Rémi; Sivaramakrishnan, Anand; Song, Inseok; Thomas, Sandrine; Wallace, J. Kent; Wang, Jason J.; Wolff, Schuyler G.

    2015-01-28

    We report he first results from the polarimetry mode of the Gemini Planet Imager (GPI), which uses a new integral field polarimetry architecture to provide high contrast linear polarimetry with minimal systematic biases between the orthogonal polarizations. We describe the design, data reduction methods, and performance of polarimetry with GPI. Point-spread function (PSF) subtraction via differential polarimetry suppresses unpolarized starlight by a factor of over 100, and provides sensitivity to circumstellar dust reaching the photon noise limit for these observations. In the case of the circumstellar disk around HR 4796A, GPI’s advanced adaptive optics system reveals the disk clearly even prior to PSF subtraction. In polarized light, the disk is seen all the way in to its semi-minor axis for the first time. The disk exhibits surprisingly strong asymmetry in polarized intensity, with the west side ≳9 times brighter than the east side despite the fact that the east side is slightly brighter in total intensity. Based on a synthesis of the total and polarized intensities, we now believe that the west side is closer to us, contrary to most prior interpretations. Forward scattering by relatively large silicate dust particles leads to the strong polarized intensity on the west side, and the ring must be slightly optically thick in order to explain the lower brightness in total intensity there. In conclusion, these findings suggest that the ring is geometrically narrow and dynamically cold, perhaps shepherded by larger bodies in the same manner as Saturn’s F ring.

  9. POLARIMETRY WITH THE GEMINI PLANET IMAGER: METHODS, PERFORMANCE AT FIRST LIGHT, AND THE CIRCUMSTELLAR RING AROUND HR 4796A

    SciTech Connect (OSTI)

    Perrin, Marshall D.; Duchene, Gaspard; Graham, James R.; Kalas, Paul G.; Millar-Blanchaer, Max; Fitzgerald, Michael P.; Chilcote, Jeffrey; Wiktorowicz, Sloane J.; Dillon, Daren; Gavel, Donald; Macintosh, Bruce; Bauman, Brian; Cardwell, Andrew; Goodsell, Stephen; Hartung, Markus; Hibon, Pascale; De Rosa, Robert J.; Doyon, Ren; Dunn, Jennifer; Erikson, Darren; and others

    2015-02-01

    We present the first results from the polarimetry mode of the Gemini Planet Imager (GPI), which uses a new integral field polarimetry architecture to provide high contrast linear polarimetry with minimal systematic biases between the orthogonal polarizations. We describe the design, data reduction methods, and performance of polarimetry with GPI. Point-spread function (PSF) subtraction via differential polarimetry suppresses unpolarized starlight by a factor of over 100, and provides sensitivity to circumstellar dust reaching the photon noise limit for these observations. In the case of the circumstellar disk around HR4796A, GPI's advanced adaptive optics system reveals the disk clearly even prior to PSF subtraction. In polarized light, the disk is seen all the way in to its semi-minor axis for the first time. The disk exhibits surprisingly strong asymmetry in polarized intensity, with the west side ? 9 times brighter than the east side despite the fact that the east side is slightly brighter in total intensity. Based on a synthesis of the total and polarized intensities, we now believe that the west side is closer to us, contrary to most prior interpretations. Forward scattering by relatively large silicate dust particles leads to the strong polarized intensity on the west side, and the ring must be slightly optically thick in order to explain the lower brightness in total intensity there. These findings suggest that the ring is geometrically narrow and dynamically cold, perhaps shepherded by larger bodies in the same manner as Saturn's F ring.

  10. Dependence of the magnitude and direction of the persistent current on the magnetic flux in superconducting rings

    SciTech Connect (OSTI)

    Gurtovoi, V. L.; Dubonos, S. V.; Nikulov, A. V. Osipov, N. N.; Tulin, V. A.

    2007-12-15

    The obtained periodic magnetic-field dependences I{sub c+}({phi}/{phi}{sub 0}) and I{sub c-}({phi}/{phi}{sub 0}) of the critical current measured in opposite directions on asymmetric superconducting aluminum rings has made it possible to explain previously observed quantum oscillations of dc voltage as a result of alternating current rectification. It was found that a higher rectification efficiency of both single rings and ring systems is caused by hysteresis of the current-voltage characteristics. The asymmetry of current-voltage characteristics providing the rectification effect is due to the relative shifts of the magnetic dependences I{sub c-}({phi}/{phi}{sub 0}) = I{sub c+}({phi}/{phi}{sub 0} + {delta}{phi}) of the critical current measured in opposite directions. This shift means that the position of I{sub c+}({phi}/{phi}{sub 0}) and I{sub c-}({phi}/{phi}{sub 0}) minima does not correspond to n + 0.5 magnetic flux {phi} quanta, which is in direct contradiction to measured Little-Parks resistance oscillations. Despite this contradiction, the amplitude I{sub c,an}({phi}/{phi}{sub 0}) = I{sub c+}({phi}/{phi}{sub 0}) - I{sub c-}({phi}/{phi}{sub 0}) of critical current anisotropy oscillations and its variations with temperature correspond to the expected amplitude of persistent current oscillations and its variations with temperature.

  11. Using compressive sensing to recover images from PET scanners with partial detector rings

    SciTech Connect (OSTI)

    Valiollahzadeh, SeyyedMajid; Clark, John W.; Mawlawi, Osama

    2015-01-15

    Purpose: Most positron emission tomography/computed tomography (PET/CT) scanners consist of tightly packed discrete detector rings to improve scanner efficiency. The authors’ aim was to use compressive sensing (CS) techniques in PET imaging to investigate the possibility of decreasing the number of detector elements per ring (introducing gaps) while maintaining image quality. Methods: A CS model based on a combination of gradient magnitude and wavelet domains (wavelet-TV) was developed to recover missing observations in PET data acquisition. The model was designed to minimize the total variation (TV) and L1-norm of wavelet coefficients while constrained by the partially observed data. The CS model also incorporated a Poisson noise term that modeled the observed noise while suppressing its contribution by penalizing the Poisson log likelihood function. Three experiments were performed to evaluate the proposed CS recovery algorithm: a simulation study, a phantom study, and six patient studies. The simulation dataset comprised six disks of various sizes in a uniform background with an activity concentration of 5:1. The simulated image was multiplied by the system matrix to obtain the corresponding sinogram and then Poisson noise was added. The resultant sinogram was masked to create the effect of partial detector removal and then the proposed CS algorithm was applied to recover the missing PET data. In addition, different levels of noise were simulated to assess the performance of the proposed algorithm. For the phantom study, an IEC phantom with six internal spheres each filled with F-18 at an activity-to-background ratio of 10:1 was used. The phantom was imaged twice on a RX PET/CT scanner: once with all detectors operational (baseline) and once with four detector blocks (11%) turned off at each of 0 °, 90 °, 180 °, and 270° (partially sampled). The partially acquired sinograms were then recovered using the proposed algorithm. For the third test, PET images

  12. Cerenkov ring imaging and spectroscopy of charged KSTAR interactions at 11 GeV/c

    SciTech Connect (OSTI)

    Bird, P.F.

    1988-11-01

    The physics and technology of this new Cerenkov detector are discussed, including materials studies, construction techniques, and resolution measurements. Sources of resolution error are individually identified and measured where possible. The results of all studied indicate that the measurement resolution is understood. This work has led to the adoption of a large scale ring imaging detector as part of a new high energy physics spectrometer, the SLD, at the Stanford Linear Accelerator Center. Results from an amplitude analysis of strange meson final states in K/sup /minus//p ..-->.. /ovr K/sub 0//..pi../sup /minus//p interactions are presented. The data derive from a 4 event/nb exposure of the LASS (large Aperture Superconducting Solenoid) spectrometer to an 11 GeV/c K/sup /minus// beam. The data sample consists of /approximately/100,000 vents distributed over the Dalitz plot of the channel. The process is observed to be dominated by the production and decay of natural spin-parity (J/sup P/ = 1/sup /minus//,2/sup +/,3/sup /minus//,/hor ellipsis/) strange meson states. The data can be understood in terms of a simple model in which the resonant /ovr K*/sup -// are produced predominantly via natural parity exchange in the t channel. The leading K*(890), K/sub 2/*(1430), and K*(1780) resonances are clearly observed and measured, and the underlying spectroscopy is also extracted. Indications of higher mass resonance production are also shown. The observed properties of these states are used to confront current models of quark spectroscopy in strange meson systems. 94 refs., 96 figs., 23 tabs.

  13. Electromagnetic wave attenuation measurements in a ring-shaped inductively coupled air plasma

    SciTech Connect (OSTI)

    Xiaolong, Wei; Haojun, Xu; Min, Lin; Chen, Su; Jianhai, Li

    2015-05-28

    An aerocraft with the surface, inlet and radome covered large-area inductive coupled plasma (ICP) can attenuate its radar echo effectively. The shape, thickness, and electron density (N{sub e}) distribution of ICP are critical to electromagnetic wave attenuation. In the paper, an air all-quartz ICP generator in size of 20 × 20 × 7 cm{sup 3} without magnetic confinement is designed. The discharge results show that the ICP is amorphous in E-mode and ring-shaped in H-mode. The structure of ICP stratifies into core region and edge halo in H-mode, and its width and thickness changes from power and pressure. Such phenomena are explained by the distribution of RF magnetic field, the diffusion of negative ions plasma and the variation of skin depth. In addition, the theoretical analysis shows that the N{sub e} achieves nearly uniform within the electronegative core and sharply steepens in the edge. The N{sub e} of core region is diagnosed by microwave interferometer under varied conditions (pressure in range of 10–50 Pa, power in 300–700 W). Furthermore, the electromagnetic wave attenuation measurements were carried out with the air ICP in the frequencies of 4–5 GHz. The results show that the interspaced ICP is still effective to wave attenuation, and the wave attenuation increases with the power and pressure. The measured attenuation is approximately in accordance with the calculation data of finite-different time-domain simulations.

  14. Concetration and Distribution of Depleted Uranium (DU) and Beryllium (Be) in Soil and Air on Illeginni Island at Kwajalein Atoll after the Final Land-Impact Test

    SciTech Connect (OSTI)

    Robison, W L; Hamilton, T F; Martinelli, R E; Gouveia, F J; Kehl, S R; Lindman, T R; Yakuma, S C

    2010-04-22

    Re-entry vehicles on missiles launched from Vandenberg Air Force base in California re-enter at the Western Test Range, the Regan Test Site (RTS) at Kwajalein Atoll. An Environmental Assessment (EA) was written at the beginning of the program to assess potential impact of DU and Be, the major RV materials of interest from a health and environmental perspective, for both ocean and land impacts. The chemical and structural form of Be and DU in RVs is such that they are insoluble in soil water and seawater. Thus, they are not toxic to plant life on the isalnd (no soil to plant uptake.) Similarly, due to their insolubility in sea water there is no uptake of either element by fish, mollusks, shellfish, sea mammals, etc. No increase in either element has been observed in sea life around Illeginnin Island where deposition of DU and Be has occured. The critical terrestrial exposure pathway for U and Be is inhalation. Concentration of both elements in air over the test period (1989 to 2006) is lower by a factor of nearly 10,000 than the most restrictive U.S. guideline for the general public. Uranium concentrations in air are also lower by factors of 10 to 100 than concentrations of U in air in the U.S. measured by the EPA (Keith et al., 1999). U and Be concentrations in air downwind of deposition areas on Illeginni Island are essentially indistinguishable from natural background concentrations of U in air at the atolls. Thus, there are no health related issues associated with people using the island.

  15. Turn-by-Turn and Bunch-by-Bunch Transverse Profiles of a Single Bunch in a Full Ring

    SciTech Connect (OSTI)

    Kraus, R.; Fisher, A.S.; /SLAC

    2005-12-15

    The apparatus described in this paper can image the evolution of the transverse profile of a single bunch, isolated from a full PEP-II ring of 1500 bunches. Using this apparatus there are two methods of single bunch imaging; bunch-by-bunch beam profiling can image every bunch in the ring a single bunch at a time with the images of sequential bunches being in order, allowing one to see variations in beam size along a train. Turn-by-turn beam profiling images a single bunch on each successive turn it makes around the ring. This method will be useful in determining the effect that an injected bunch has on a stable bunch as the oscillations of the injected bunch damp out. Turn-by-turn imaging of the synchrotron light uses a system of lenses and mirrors to image many turns of both the major and minor axis of a single bunch across the photocathode of a gateable camera. The bunch-by-bunch method is simpler: because of a focusing mirror used in porting the light from the ring, the synchrotron light from the orbiting electrons becomes an image at a certain distance from the mirror; and since the camera does not use a lens, the photocathode is set exactly at this image distance. Bunch-by-bunch profiling has shown that in the Low Energy Ring (LER) horizontal bunch size decreases along a train. Turn-by-turn profiling has been able to image 100 turns of a single bunch on one exposure of the camera. The turn-by-turn setup has also been able to image 50 turns of the minor axis showing part of the damping process of an oscillating injected charge during a LER fill. The goal is to image the damping of oscillations of injected charge for 100 turns of both the major and minor axis throughout the damping process during trickle injection. With some changes to the apparatus this goal is within reach and will make turn-by-turn imaging a very useful tool in beam diagnostics.

  16. The orbits of the uranian satellites and rings, the gravity field of the uranian system, and the orientation of the pole of Uranus

    SciTech Connect (OSTI)

    Jacobson, R. A.

    2014-11-01

    French et al. determined the orbits of the Uranian rings, the orientation of the pole of Uranus, and the gravity harmonics of Uranus from Earth-based and Voyager ring occultations. Jacobson et al. determined the orbits of the Uranian satellites and the masses of Uranus and its satellites from Earth-based astrometry and observations acquired with the Voyager 2 spacecraft; they used the gravity harmonics and pole from French et al. Jacobson and Rush reconstructed the Voyager 2 trajectory and redetermined the Uranian system gravity parameters, satellite orbits, and ring orbits in a combined analysis of the data used previously augmented with additional Earth-based astrometry. Here we report on an extension of that work that incorporates additional astrometry and ring occultations together with improved data processing techniques.

  17. Effect of Siloxane Ring Strain and Cation Charge Density on the Formation of Coordinately Unsaturated Metal Sites on Silica: Insights from DFT Studies

    SciTech Connect (OSTI)

    Das, Ujjal; Zhang, Guanghui; Hu, Bo; Hock, Adam S.; Redfern, Paul C.; Miller, Jeffrey T.; Curtiss, Larry A.

    2015-12-01

    Amorphous silica (SiO2) is commonly used as a support in heterogeneous catalysis. However, due to the structural disorder and temperature induced change of surface morphology, the structures of silica supported metal catalysts are difficult to determine. Most studies are primarily focused on understanding the interactions of different types of surface hydroxyl groups with metal ions. In comparison, the effect of siloxane ring size on the structure of silica supported metal catalysts and how it affects catalytic activity is poorly understood. Here, we have used density functional theory calculations to understand the effect of siloxane ring strain on structure and activity of different monomeric Lewis acid metal sites on silica. In particular, we have found that large siloxane rings favor strong dative bonding interaction between metal ion and surface hydroxyls, leading to the formation of high-coordinate metal sites. In comparison, metal-silanol interaction is weak in small siloxane rings, resulting in low-coordinate metal sites. The physical origin of this size dependence is associated with siloxane ring strain, and, a correlation between metal-silanol interaction energy and ring strain energy has been observed. In addition to ring strain, the strength of the metal-silanol interaction also depends on the positive charge density of the cations. In fact, a correlation also exists between metal-silanol interaction energy and charge density of several first-row transition and post-transition metals. The theoretical results are compared with the EXAFS data of monomeric Zn(II) and Ga(III) ions grafted on silica. The molecular level insights of how metal ion coordination on silica depends on siloxane ring strain and cation charge density will be useful in the synthesis of new catalysts.

  18. Vertical emitting, ring geometry, ultra-low threshold and ultra-high speed quantum well lasers for optical interconnect. Final report Jul 88-Dec 90

    SciTech Connect (OSTI)

    Mittelstein, M.; Bar-Chaim, N.

    1991-01-01

    The main emphasis for this contract was placed on the efforts as highlighted in the chapter captions: (1) Introduction to optical interconnects, (2) Conventional laser, (3) Design of laser structures, (4) Achieving buried ring structures, (5) Buried ring quantum well structure, (6) Buried lasers: Champion results and reproducibility, (7) Ridge wave guide laser fabrication, (8) Grating fabrication, (9) Grating fabrication facility, (10) Test station, and (11) Material investigation.

  19. Responses of Conventional Ring Closures of Drum Type Packages to Regulatory Drop Tests with Application to the 9974/9975 Package

    SciTech Connect (OSTI)

    Blanton, P.S.

    2002-05-31

    DOT, DOE and NRC Type A and Type B radioactive material (RAM) transport packages routinely use industrial or military specification drums with conventional clamp ring closures as an overpack. Considerable testing has been performed on these type packages over the past 30 years. Observations from test data have resulted in various design changes and recommendations to the standard drum specification and use, enhancing the reliability of the overpack. Recently, performance capability of the 9975 conventional clamp ring closure design was questioned by the Regulatory Authority. This paper highlights the observations of recent 9974 and 9975 package testing that led to redesign of the 9975, replacing the standard clamp ring closure with a bolted ring closure. In the course of this review and redesign effort, 18 package designs and approximately 100 Hypothetical Accident Condition (HAC) drops of various size and weight drum packages were evaluated. A trend was observed with respect to overpack lid failures for packages utilizing conventional ring closure. Based on this trend, a limit on the ratio of the content weight to total package weight was identified, beyond which clamp ring closure failure may be expected.

  20. Assessment of neutron skyshine near unmodified Accumulator Debuncher storage rings under Mu2e operational conditions

    SciTech Connect (OSTI)

    Cossairt, J.Donald; /Fermilab

    2010-12-01

    Preliminary plans for providing the proton beam needed by the proposed Mu2e experiment at Fermilab will require the transport of 8 GeV protons to the Accumulator/Debuncher where they be processed into an intensity and time structure useful for the experiment. The intensities involved are far greater that those encountered with antiprotons of the same kinetic energy in the same beam enclosures under Tevatron Collider operational conditions, the operating parameters for which the physical facilities of the Antiproton Source were designed. This note explores some important ramifications of the proposed operation for radiation safety and demonstrates the need for extensive modifications of significant portions of the shielding of the Accumulator Debuncher storage rings; notably that underneath the AP Service Buildings AP10, AP30, and AP50. While existing shielding is adequate for the current operating mode of the Accumulator/Debuncher as part of the Antiproton Source used in the Tevatron Collider program, without significant modifications of the shielding configuration in the Accumulator/Debuncher region and/or beam loss control systems far more effective than seen in most applications at Fermilab, the proposed operational mode for Mu2e is not viable for the following reasons: 1. Due to skyshine alone, under normal operational conditions large areas of the Fermilab site would be exposed to unacceptable levels of radiation where most of the Laboratory workforce and some members of the general public who regularly visit Fermilab would receive measurable doses annually, contrary to workforce, public, and DOE expectations concerning the As Low as Reasonably Achievable (ALARA) principle. 2. Under normal operational conditions, a sizeable region of the Fermilab site would also require fencing due to skyshine. The size of the areas involved would likely invite public inquiry about the significant and visible enlargement of Fermilab's posted radiological areas. 3. There would

  1. Ring Walking/Oxidative Addition Reactions for the Controlled Synthesis of Conjugated Polymers

    SciTech Connect (OSTI)

    Bazan, Guillermo C

    2012-04-03

    Power conversion efficiencies of plastic solar cells depend strongly on the molecular weight characteristics of the semiconducting polymers used for their fabrication. The synthesis of these materials typically relies on transition metal mediated catalytic reactions. In many instances, the ideal structures cannot be attained because of deficiencies in these reactions, particularly when it comes to being able to achieve high number average molecular weights and narrow molecular weight distributions. Another important conjugated polymer structure of interest is one in which a single functional group is attached at the end group of the chain. Such systems would be ideal for modifying surface properties at interfaces and for labeling biomolecular probes used in fluorescent biosensors. To respond to the challenges above, our efforts have centered on the design of homogenous transition metal complexes that are easy to prepare and effective in carrying out living, or quasi-living, condensative chain polymerization reactions. The key mechanistic challenge for the success of this reaction is to force the insertion of one monomer unit at a time via a process that involves migration of the transition metal-containing fragment to one terminus of the polymer chain. Chain growth characteristics are therefore favored when the metal does not dissociate from the newly formed reductive elimination product. We have proposed that dissociation is disfavored by the formation of a ?-complex, in which the metal can sample various locations of the electronically delocalized framework, a process that we term ??ring-walking?, and find the functionality where oxidative addition takes place. Success has been achieved in the nickel-mediated cross coupling reaction of Grignard reagents with aromatic halides by using bromo[1,2-bis(diphenylphosphino)ethane]phenylnickel. This reagent can yield poly(thiophene)s (one of the most widely used type of polymer in plastic solar cells) with excellent

  2. Quantifying Contaminant Mass for the Feasibility Study of the DuPont Chambers Works FUSRAP Site - 13510

    SciTech Connect (OSTI)

    Young, Carl; Rahman, Mahmudur; Johnson, Ann; Owe, Stephan

    2013-07-01

    The U.S. Army Corps of Engineers (USACE) - Philadelphia District is conducting an environmental restoration at the DuPont Chambers Works in Deepwater, New Jersey under the Formerly Utilized Sites Remedial Action Program (FUSRAP). Discrete locations are contaminated with natural uranium, thorium-230 and radium-226. The USACE is proposing a preferred remedial alternative consisting of excavation and offsite disposal to address soil contamination followed by monitored natural attenuation to address residual groundwater contamination. Methods were developed to quantify the error associated with contaminant volume estimates and use mass balance calculations of the uranium plume to estimate the removal efficiency of the proposed alternative. During the remedial investigation, the USACE collected approximately 500 soil samples at various depths. As the first step of contaminant mass estimation, soil analytical data was segmented into several depth intervals. Second, using contouring software, analytical data for each depth interval was contoured to determine lateral extent of contamination. Six different contouring algorithms were used to generate alternative interpretations of the lateral extent of the soil contamination. Finally, geographical information system software was used to produce a three dimensional model in order to present both lateral and vertical extent of the soil contamination and to estimate the volume of impacted soil for each depth interval. The average soil volume from all six contouring methods was used to determine the estimated volume of impacted soil. This method also allowed an estimate of a standard deviation of the waste volume estimate. It was determined that the margin of error for the method was plus or minus 17% of the waste volume, which is within the acceptable construction contingency for cost estimation. USACE collected approximately 190 groundwater samples from 40 monitor wells. It is expected that excavation and disposal of

  3. Influence of plasma beta on the generation of lower hybrid and whistler waves by an ion velocity ring distribution

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

    Winske, D.; Daughton, W.

    2015-02-02

    We present results of three-dimensional electromagnetic particle-in-cell simulations of the lower hybrid ion ring instability, similar to our earlier results [D. Winske and W. Daughton, Phys. Plasma, 19, 072109, 2012], but at higher electron beta (βe = ratio of electron thermal pressure to magnetic pressure = 0.06, rather than at 0.006) with Ti = Te. At higher electron beta the level of lower hybrid waves at saturation normalized to the ion thermal energy (βi = 0.06 also) is only slightly smaller, but the corresponding magnetic fluctuations are about an order of magnitude larger, consistent with linear theory. After saturation, themore » waves evolve into whistler waves, through a number of possible mechanisms, with an average growth rate considerably smaller than the linear growth rate of the lower hybrid waves, to a peak fluctuation level that is about 20% above the lower hybrid wave saturation level. The ratio of the peak magnetic fluctuations associated with the whistler waves relative to those of the saturated lower hybrid waves, the ratio of the nonlinear growth rate of whistlers relative to the linear growth rate of lower hybrid waves, the amount of energy extracted from the ring and the amount of heating of the background ions and electrons are comparable to those in the lower electron beta 3-D simulation. This suggests that even at higher electron beta, the linear and nonlinear physics of the lower hybrid ion ring instability is dominated by electrostatic, wave-particle rather than wave-wave interactions.« less

  4. Polarimetry with the Gemini Planet Imager. Methods, performance at first light, and the circumstellar ring around HR 4796A

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

    Perrin, Marshall D.; Duchene, Gaspard; Millar-Blanchaer, Max; Fitzgerald, Michael P.; Graham, James R.; Wiktorowicz, Sloane J.; Kalas, Paul G.; Macintosh, Bruce; Bauman, Brian; Cardwell, Andrew; et al

    2015-01-28

    We report he first results from the polarimetry mode of the Gemini Planet Imager (GPI), which uses a new integral field polarimetry architecture to provide high contrast linear polarimetry with minimal systematic biases between the orthogonal polarizations. We describe the design, data reduction methods, and performance of polarimetry with GPI. Point-spread function (PSF) subtraction via differential polarimetry suppresses unpolarized starlight by a factor of over 100, and provides sensitivity to circumstellar dust reaching the photon noise limit for these observations. In the case of the circumstellar disk around HR 4796A, GPI’s advanced adaptive optics system reveals the disk clearly evenmore » prior to PSF subtraction. In polarized light, the disk is seen all the way in to its semi-minor axis for the first time. The disk exhibits surprisingly strong asymmetry in polarized intensity, with the west side ≳9 times brighter than the east side despite the fact that the east side is slightly brighter in total intensity. Based on a synthesis of the total and polarized intensities, we now believe that the west side is closer to us, contrary to most prior interpretations. Forward scattering by relatively large silicate dust particles leads to the strong polarized intensity on the west side, and the ring must be slightly optically thick in order to explain the lower brightness in total intensity there. In conclusion, these findings suggest that the ring is geometrically narrow and dynamically cold, perhaps shepherded by larger bodies in the same manner as Saturn’s F ring.« less

  5. Influence of plasma beta on the generation of lower hybrid and whistler waves by an ion velocity ring distribution

    SciTech Connect (OSTI)

    Winske, D.; Daughton, W.

    2015-02-02

    We present results of three-dimensional electromagnetic particle-in-cell simulations of the lower hybrid ion ring instability, similar to our earlier results [D. Winske and W. Daughton, Phys. Plasma, 19, 072109, 2012], but at higher electron beta (βe = ratio of electron thermal pressure to magnetic pressure = 0.06, rather than at 0.006) with Ti = Te. At higher electron beta the level of lower hybrid waves at saturation normalized to the ion thermal energy (βi = 0.06 also) is only slightly smaller, but the corresponding magnetic fluctuations are about an order of magnitude larger, consistent with linear theory. After saturation, the waves evolve into whistler waves, through a number of possible mechanisms, with an average growth rate considerably smaller than the linear growth rate of the lower hybrid waves, to a peak fluctuation level that is about 20% above the lower hybrid wave saturation level. The ratio of the peak magnetic fluctuations associated with the whistler waves relative to those of the saturated lower hybrid waves, the ratio of the nonlinear growth rate of whistlers relative to the linear growth rate of lower hybrid waves, the amount of energy extracted from the ring and the amount of heating of the background ions and electrons are comparable to those in the lower electron beta 3-D simulation. This suggests that even at higher electron beta, the linear and nonlinear physics of the lower hybrid ion ring instability is dominated by electrostatic, wave-particle rather than wave-wave interactions.

  6. Three-dimensional ordering of cold ion beams in a storage ring: A molecular-dynamics simulation study

    SciTech Connect (OSTI)

    Yuri, Yosuke

    2015-06-29

    Three-dimensional (3D) ordering of a charged-particle beams circulating in a storage ring is systematically studied with a molecular-dynamics simulation code. An ion beam can exhibit a 3D ordered configuration at ultralow temperature as a result of powerful 3D laser cooling. Various unique characteristics of the ordered beams, different from those of crystalline beams, are revealed in detail, such as the single-particle motion in the transverse and longitudinal directions, and the dependence of the tune depression and the Coulomb coupling constant on the operating points.

  7. On the role of delocalization in benzene: Theoretical and experimental investigation of the effects of strained ring fusion

    SciTech Connect (OSTI)

    Faust, R.

    1993-04-01

    When an important compound`s discovery dates back as far as 1825, one would imagine that every facet of its chemical and physical properties has been illuminated in the meantime. Benzene, however, has not ceased to challenge the chemist`s notion of structure and bonding since its first isolation by Michael Faraday. This report is divided into the following six chapters: 1. Aromaticity -- Criteria, manifestations, structural limitations; 2. The role of delocalization in benzene; 3. The thermochemical properties of benzocyclobutadienologs; 4. Ab initio study of benzenes fused to four-membered rings; 5. Non-planar polycyclic aromatic hydrocarbons; and 6. Experimental details and input decks. 210 Refs.

  8. Required cavity HOM deQing calculated from probability estimates of coupled bunch instabilities in the APS ring

    SciTech Connect (OSTI)

    Emery, L.

    1993-06-01

    A method of determining the deQing requirement of individual cavity higher-order modes (HOM) for a multi-cavity RF system is presented and applied to the APS ring. Since HOM resonator frequency values are to some degree uncertain, the HOM frequencies should be regarded as random variables in predicting the stability of the coupled bunch beam modes. A Monte Carlo simulation provides a histogram of the growth rates from which one obtains an estimate of the probability of instability. The damping of each HOM type is determined such that the damping effort is economized, i.e. no single HOM dominates the specified growth rate histogram.

  9. No-carrier-added (NCA) aryl (18E) fluorides via the nucleophilic aromatic substitution of electron rich aromatic rings

    DOE Patents [OSTI]

    Ding, Yu-Shin; Fowler, Joanna S.; Wolf, Alfred P.

    1993-01-01

    A method for synthesizing no-carrier-added (NCA) aryl [.sup.18 F] fluoride substituted aromatic aldehyde compositions bearing an electron donating group is described. The method of the present invention includes the step of reacting aromatic nitro aldehydes having a suitably protected hydroxyl substitutent on an electron rich ring. The reaction is The U.S. Government has rights in this invention pursuant to Contract Number DE-AC02-76CH00016, between the U.S. Department of Energy and Associated Universities Inc.

  10. No-carrier-added (NCA) aryl ([sup 18]F) fluorides via the nucleophilic aromatic substitution of electron rich aromatic rings

    DOE Patents [OSTI]

    Yushin Ding; Fowler, J.S.; Wolf, A.P.

    1993-10-19

    A method for synthesizing no-carrier-added (NCA) aryl [.sup.18 F] fluoride substituted aromatic aldehyde compositions bearing an electron donating group is described. The method of the present invention includes the step of reacting aromatic nitro aldehydes having a suitably protected hydroxyl substitutent on an electron rich ring. The reaction is The U.S. Government has rights in this invention pursuant to Contract Number DE-AC02-76CH00016, between the U.S. Department of Energy and Associated Universities Inc.

  11. A DOUBLE-RING ALGORITHM FOR MODELING SOLAR ACTIVE REGIONS: UNIFYING KINEMATIC DYNAMO MODELS AND SURFACE FLUX-TRANSPORT SIMULATIONS

    SciTech Connect (OSTI)

    Munoz-Jaramillo, Andres; Martens, Petrus C. H.; Nandy, Dibyendu; Yeates, Anthony R. E-mail: dnandi@iiserkol.ac.i E-mail: anthony@maths.dundee.ac.u

    2010-09-01

    The emergence of tilted bipolar active regions (ARs) and the dispersal of their flux, mediated via processes such as diffusion, differential rotation, and meridional circulation, is believed to be responsible for the reversal of the Sun's polar field. This process (commonly known as the Babcock-Leighton mechanism) is usually modeled as a near-surface, spatially distributed {alpha}-effect in kinematic mean-field dynamo models. However, this formulation leads to a relationship between polar field strength and meridional flow speed which is opposite to that suggested by physical insight and predicted by surface flux-transport simulations. With this in mind, we present an improved double-ring algorithm for modeling the Babcock-Leighton mechanism based on AR eruption, within the framework of an axisymmetric dynamo model. Using surface flux-transport simulations, we first show that an axisymmetric formulation-which is usually invoked in kinematic dynamo models-can reasonably approximate the surface flux dynamics. Finally, we demonstrate that our treatment of the Babcock-Leighton mechanism through double-ring eruption leads to an inverse relationship between polar field strength and meridional flow speed as expected, reconciling the discrepancy between surface flux-transport simulations and kinematic dynamo models.

  12. Sensitivity to electronvolt-scale sterile neutrinos at a 3.8-GeV/c muon decay ring

    SciTech Connect (OSTI)

    Tunnell, Christopher D.

    2013-03-01

    The liquid-scintillator neutrino-detector (LSND) and mini booster neutrino experiment (MiniBooNE) experiments claim to observe the oscillation $\\bar{v}$μ → $\\bar{v}$e, which can only be explained by additional neutrinos and is a claim that must be further tested. This thesis proposes a new accelerator and experiment called neutrinos from stored muons ( STORM) to refute or confirm the oscillation these claims by studying the CPT-equivalent channel ve → vμ . A 3.8-GeV/c muon decay ring is proposed with neutrino detectors placed 20 m and 2000 m from the decay ring. The detector technology would be a magnetized iron sampling calorimeter, where the magnetic field is induced by a superconducting transmission line. In a frequentist study, the sensitivity of this experiment after 5 years would be >10σ . The range of the thesis discussion starts with the proton front-end design and ends with neutrino parameter estimation. After describing the phenomenology of sterile neutrinos, the facility and detector performance work is presented. Finally, the systematics are explained before the sensitivity and parameter-estimation works are explained

  13. Residual stress analysis of alloy 600 U-bends, reverse U-bends, and C-rings: Final report

    SciTech Connect (OSTI)

    Rudd, C.O.

    1994-11-01

    Over the last several years, one of the leading causes of alloy 600 steam generator tubing leaks has been the primary-side-initiated, intergranular stress corrosion cracking (IGSCC) in heavily cold-worked regions of the U-bends or tubesheet expansion transitions. Field and laboratory experiences have demonstrated that high residual stresses contribute significantly to the initiation of primary water stress corrosion cracking (PWSCC). EPRI initiated this project to measure and quantify the magnitude of these residual stresses in steam generator tubes as well as in various laboratory tests specimens. the objectives were: To measure the residual stresses in steam generator tube U-bends; To measure residual stresses in reverse U-bend (RUB) specimens as well as residual stresses and X-ray diffraction peak broadening in C-ring specimens used in laboratory tests; and To determine whether residual stress occurs as a result of exposure to steam generator operating temperature. Using an advanced X-ray instrument, investigators measured residual stresses on both the outside diameter (OD) and inside diameter (ID) surfaces and subsurfaces of steam generator U-bends and on the test surfaces of laboratory RUB and C-ring specimens. They measured these residual stresses in the hoop and axial directions and also calculated equivalent stresses. Results are discussed. 25 refs., 92 figs., 6 tabs.

  14. WE-A-17A-05: Differences in Applicator Configuration and Dwell Loading Between Standard and Image-Guided Tandem and Ring (T and R) HDR Brachytherapy

    SciTech Connect (OSTI)

    Damato, A; Cormack, R; Bhagwat, M; Buzurovic, I; Lee, L; Viswanathan, A

    2014-06-15

    Purpose: To investigate differences in: (i) relative location of the tandem and the ring compared to a rigid standard applicator model; and (ii) relative loading and changes in loading pattern between standard and image-guided planning. Methods: All T and R insertions performed in 2013 in our institution under CT- or MR-guidance were analyzed. Standard plans were generated using library applicator models with a fixed relationship between ring and tandem, standardized uniform dwell loading and normalization to point A. The graphic plans and the associated standard-plan dwell configurations were compared: the rings were rigidly registered, and the residual tandem shift, rotation and maximum distance between plan tandem dwell and corresponding model tandem dwell were calculated. The normalization ratio (NR = the ratio of graphic versus standard-plan total reference air kerma [TRAK]), the general loading difference (GLD = the difference between graphic and standard ratios of the tandem versus the ring TRAK), and the percent standard deviation (SD% = SD/mean) of the tandem and the ring TRAK for the graphic plan (all standard-plans SD% = 0) were calculated. Results: 71 T and R were analyzed. Residual tandem shift, rotation and maximum corresponding dwell distance were 1.2±0.8mm (0.4±0.4mm lateral, 0.9±0.8mm craniocaudal, 0.4±0.3mm anterior-posterior), 2.3±1.9deg and 3.4±2.3mm. NR was 0.86±0.11 indicating a lower overall loading of the graphic compared to the standard plans. GLD was -0.12±0.16 indicating a modest increased ring loading relative to the tandem in the graphic plans. SD% was 2.1±1.6% for tandem and 2.8±1.9% for ring, indicating small deviations from uniform loading. Conclusion: Variability in the relative locations of the tandem and the ring necessitates the independent registration of each component model for accurate digitization. Our clinical experience suggests that graphically planned T and R results on average in a lower total dose to the

  15. TESTING THE HYPOTHESIS THAT METHANOL MASER RINGS TRACE CIRCUMSTELLAR DISKS: HIGH-RESOLUTION NEAR-INFRARED AND MID-INFRARED IMAGING

    SciTech Connect (OSTI)

    De Buizer, James M.; Bartkiewicz, Anna; Szymczak, Marian

    2012-08-01

    Milliarcsecond very long baseline interferometry maps of regions containing 6.7 GHz methanol maser emission have lead to the recent discovery of ring-like distributions of maser spots and the plausible hypothesis that they may be tracing circumstellar disks around forming high-mass stars. We aimed to test this hypothesis by imaging these regions in the near- and mid-infrared at high spatial resolution and compare the observed emission to the expected infrared morphologies as inferred from the geometries of the maser rings. In the near-infrared we used the Gemini North adaptive optics system of ALTAIR/NIRI, while in the mid-infrared we used the combination of the Gemini South instrument T-ReCS and super-resolution techniques. Resultant images had a resolution of {approx}150 mas in both the near-infrared and mid-infrared. We discuss the expected distribution of circumstellar material around young and massive accreting (proto)stars and what infrared emission geometries would be expected for the different maser ring orientations under the assumption that the masers are coming from within circumstellar disks. Based upon the observed infrared emission geometries for the four targets in our sample and the results of spectral energy distribution modeling of the massive young stellar objects associated with the maser rings, we do not find compelling evidence in support of the hypothesis that methanol masers rings reside in circumstellar disks.

  16. Spin-polarization and spin-dependent logic gates in a double quantum ring based on Rashba spin-orbit effect: Non-equilibrium Green's function approach

    SciTech Connect (OSTI)

    Eslami, Leila, E-mail: Leslami@iust.ac.ir; Esmaeilzadeh, Mahdi, E-mail: mahdi@iust.ac.ir [Department of Physics, Iran University of Science and Technology, Tehran 16846 (Iran, Islamic Republic of)

    2014-02-28

    Spin-dependent electron transport in an open double quantum ring, when each ring is made up of four quantum dots and threaded by a magnetic flux, is studied. Two independent and tunable gate voltages are applied to induce Rashba spin-orbit effect in the quantum rings. Using non-equilibrium Green's function formalism, we study the effects of electron-electron interaction on spin-dependent electron transport and show that although the electron-electron interaction induces an energy gap, it has no considerable effect when the bias voltage is sufficiently high. We also show that the double quantum ring can operate as a spin-filter for both spin up and spin down electrons. The spin-polarization of transmitted electrons can be tuned from ?1 (pure spin-down current) to +1 (pure spin-up current) by changing the magnetic flux and/or the gates voltage. Also, the double quantum ring can act as AND and NOR gates when the system parameters such as Rashba coefficient are properly adjusted.

  17. Criteria of radio-frequency ring-shaped hollow cathode discharge using H{sub 2} and Ar gases for plasma processing

    SciTech Connect (OSTI)

    Ohtsu, Yasunori; Kawasaki, Yujiro

    2013-01-21

    In order to achieve high-density capacitively coupled plasma, a radio-frequency (RF) ring-shaped hollow cathode discharge has been developed as a candidate for processing plasma sources. The plasma density in the hollow cathode discharge reaches a high magnitude of 10{sup 10}-10{sup 11} cm{sup -3}. The RF ring-shaped hollow cathode discharge depends on the pressure and mass of the working gas. Criteria required for producing a RF ring-shaped hollow cathode discharge have been investigated for various gas pressures using H{sub 2} and Ar gases for high-density plasma production. The results reveal that the criteria for the occurrence of the hollow cathode effect are that the trench width should be approximately equal to the sum of the electron-neutral mean free paths and twice the sheath thickness of the RF powered electrode.

  18. Reduction of ring artifacts in CBCT: Detection and correction of pixel gain variations in flat panel detectors

    SciTech Connect (OSTI)

    Altunbas, Cem; Lai, Chao-Jen; Zhong, Yuncheng; Shaw, Chris C.

    2014-09-15

    Purpose: In using flat panel detectors (FPD) for cone beam computed tomography (CBCT), pixel gain variations may lead to structured nonuniformities in projections and ring artifacts in CBCT images. Such gain variations can be caused by change in detector entrance exposure levels or beam hardening, and they are not accounted by conventional flat field correction methods. In this work, the authors presented a method to identify isolated pixel clusters that exhibit gain variations and proposed a pixel gain correction (PGC) method to suppress both beam hardening and exposure level dependent gain variations. Methods: To modulate both beam spectrum and entrance exposure, flood field FPD projections were acquired using beam filters with varying thicknesses. “Ideal” pixel values were estimated by performing polynomial fits in both raw and flat field corrected projections. Residuals were calculated by taking the difference between measured and ideal pixel values to identify clustered image and FPD artifacts in flat field corrected and raw images, respectively. To correct clustered image artifacts, the ratio of ideal to measured pixel values in filtered images were utilized as pixel-specific gain correction factors, referred as PGC method, and they were tabulated as a function of pixel value in a look-up table. Results: 0.035% of detector pixels lead to clustered image artifacts in flat field corrected projections, where 80% of these pixels were traced back and linked to artifacts in the FPD. The performance of PGC method was tested in variety of imaging conditions and phantoms. The PGC method reduced clustered image artifacts and fixed pattern noise in projections, and ring artifacts in CBCT images. Conclusions: Clustered projection image artifacts that lead to ring artifacts in CBCT can be better identified with our artifact detection approach. When compared to the conventional flat field correction method, the proposed PGC method enables characterization of nonlinear

  19. Aging Behavior of Viton{sup R} O-Ring Seals in the 9975 Shipping Package - 12594

    SciTech Connect (OSTI)

    Skidmore, T. Eric; Daugherty, William L.; Hoffman, Elizabeth N.; Dunn, Kerry A.; Stephen Bellamy, J.; Shuler, James M.

    2012-07-01

    The Savannah River Site (SRS) is storing plutonium (Pu) materials in the K-Area Materials Storage (KAMS) facility. The Pu materials were packaged according to the DOE-STD-3013 standard and shipped to the SRS in Type B 9975 packages. The robust 9975 shipping package was not designed for long-term product storage, but it is a specified part of the storage configuration and the KAMS facility safety basis credits the 9975 design with containment. Within the 9975 package, nested stainless steel containment vessels are closed with dual O-ring seals based on Viton{sup R} GLT or GLT-S fluoro-elastomer. The aging behavior of the O-ring compounds is being studied to provide the facility with advanced notice of nonconformance and to develop life prediction models. A combination of field surveillance, leak testing of surrogate fixtures aged at bounding service temperatures, and accelerated-aging methodologies based on compression stress-relaxation and oxygen consumption analysis is being used to evaluate seal performance. A summary of the surveillance program relative to seal aging behavior is presented. The aging behavior of fluoro-elastomer seals based on Viton{sup R} GLT and GLT-S is being studied to develop life prediction models in support of long-term storage of plutonium materials in the 9975 shipping packages at the Savannah River Site. Field surveillance data in combination with accelerated-aging data suggest a significant lifetime for the seals. Typical storage conditions are not anticipated to challenge the leak-tightness of the seals for many years. Early life prediction models based on compression stress relaxation indicate a seal lifetime of ?12 years at the maximum service temperature predicted (93 deg. C). Seal lifetimes at lower, more realistic conditions are likely significantly longer. Service life predictions based on CSR data are thus far conservative relative to predictions based on time to leakage failure. Surveillance data on packages examined after 6

  20. A proposed design and fabrication of lenses and mirrors from a set of spherical rings that produce desired energy distributions for solar energy applications

    SciTech Connect (OSTI)

    Gonzalez-Garcia, Jorge; Vazquez-Montiel, Sergio; Santiago-Alvarado, Agustin; Cordero-Davila, Alberto; Castro-Gonzalez, Graciela

    2009-12-15

    The amount of energy contained in the solar aureole affects the performance of solar systems. Solar optical systems are, therefore, dependent on the characteristics of the shape of the sun in a specific geographical location. For this reason, the present study proposes the design of solid lenses and mirrors modelled from a set of concentric spherical rings that give a desired distribution of energy in the focal plane. One hundred spherical rings, whose optimum curvature radius values were calculated by Genetic Algorithms, were employed in the modelling process. The study also proposes a design of a petal tool to polish lens and mirror surfaces. (author)