National Library of Energy BETA

Sample records for latitude tilt irradiance

  1. Dipole tilt angle effects on the latitude of the cusp and cleft/low-latitude boundary layer

    SciTech Connect (OSTI)

    Newell, P.T.; Meng, C.I. (Johns Hopkins Univ., Laurel, MD (USA))

    1989-06-01

    A large data set of approximately 12,000 Defense Meteorological Satellite Program satellite F7 crossings of the cusp or the cleft (i.e., the dayside magnetospheric boundary layer) over a 3-year period is studied for seasonal dependence in latitudinal position. A carefully tested algorithm is used to distinguish the various dayside particle precipitation regions and boundaries. It is found that in the 1,100-1,300 MLT sector, the cusp proper exhibits about {minus}0.06{degree} magnetic latitude (MLAT) shift for each degree increase in dipole tilt angle. Thus the difference between the average summer and winter cusp positions is close to 4{degree} MLAT, approximately symmetric about equinox. For the cleft (magnetospheric boundary layer) the variation is smaller. For example, in the 0700-0900 MLT sector the cleft equatorward boundary shift is {minus} 0.027{degree} MLAT/1{degree} dipole tilt. These results are in general agreement with the predictions of empirical magnetospheric magnetic field models. Various ground-based and low-altitude observations can be systematically affected by the seasonal latitudinal shift herein documented.

  2. A Method of Correcting for Tilt From Horizontal in Downwelling Shortwave Irradiance Measurements on Moving Platforms

    SciTech Connect (OSTI)

    Long, Charles N.; Bucholtz, Anthony; Jonsson, Haf; Schmid, Beat; Vogelmann, A. M.; Wood, John

    2010-04-14

    Significant errors occur in downwelling shortwave irradiance measurements made on moving platforms due to tilt from horizontal because, when the sun is not completely blocked by overhead cloud, the downwelling shortwave irradiance has a prominent directional component from the direct sun. A-priori knowledge of the partitioning between the direct and diffuse components of the total shortwave irradiance is needed to properly apply a correction for tilt. This partitioning information can be adequately provided using a newly available commercial radiometer that produces reasonable measurements of the total and diffuse shortwave irradiance, and by subtraction the direct shortwave irradiance, with no moving parts and regardless of azimuthal orientation. We have developed methodologies for determining the constant pitch and roll offsets of the radiometers for aircraft applications, and for applying a tilt correction to the total shortwave irradiance data. Results suggest that the methodology is for tilt up to +/-10°, with 90% of the data corrected to within 10 Wm-2 at least for clear-sky data. Without a proper tilt correction, even data limited to 5° of tilt as is typical current practice still exhibits large errors, greater than 100 Wm-2 in some cases. Given the low cost, low weight, and low power consumption of the SPN1 total and diffuse radiometer, opportunities previously excluded for moving platform measurements such as small Unmanned Aerial Vehicles and solar powered buoys now become feasible using our methodology. The increase in measurement accuracy is important, given current concerns over long-term climate variability and change especially over the 70% of the Earth’s surface covered by ocean where long-term records of these measurements are sorely needed and must be made on ships and buoys.

  3. Measurement and modeling of solar irradiance components on horizontal and tilted planes

    SciTech Connect (OSTI)

    Padovan, Andrea; Col, Davide del

    2010-12-15

    In this work new measurements of global and diffuse solar irradiance on the horizontal plane and global irradiance on planes tilted at 20 and 30 oriented due South and at 45 and 65 oriented due East are used to discuss the modeling of solar radiation. Irradiance data are collected in Padova (45.4 N, 11.9 E, 12 m above sea level), Italy. Some diffuse fraction correlations have been selected to model the hourly diffuse radiation on the horizontal plane. The comparison with the present experimental data shows that their prediction accuracy strongly depends on the sky characteristics. The hourly irradiance measurements taken on the tilted planes are compared with the estimations given by one isotropic and three anisotropic transposition models. The use of an anisotropic model, based on a physical description of the diffuse radiation, provides a much better accuracy, especially when measurements of the diffuse irradiance on the horizontal plane are not available and thus transposition models have to be applied in combination with a diffuse fraction correlation. This is particularly significant for the planes oriented away from South. (author)

  4. DERIVED CATEGORIES AND TILTING BERNHARD KELLER

    E-Print Network [OSTI]

    Keller, Bernhard - Institut de Mathématiques de Jussieu, Université Paris 7

    DERIVED CATEGORIES AND TILTING BERNHARD KELLER Abstract. We review the basic definitions of derived categories and deri* *ved functors. We that each tilting triple yields an* * equiv- alence between derived categories. We establish its

  5. Tilting Saturn without tilting Jupiter: Constraints on giant planet migration

    E-Print Network [OSTI]

    Brasser, R

    2015-01-01

    The migration and encounter histories of the giant planets in our Solar System can be constrained by the obliquities of Jupiter and Saturn. We have performed secular simulations with imposed migration and N-body simulations with planetesimals to study the expected obliquity distribution of migrating planets with initial conditions resembling those of the smooth migration model, the resonant Nice model and two models with five giant planets initially in resonance (one compact and one loose configuration). For smooth migration, the secular spin-orbit resonance mechanism can tilt Saturn's spin axis to the current obliquity if the product of the migration time scale and the orbital inclinations is sufficiently large (exceeding 30 Myr deg). For the resonant Nice model with imposed migration, it is difficult to reproduce today's obliquity values, because the compactness of the initial system raises the frequency that tilts Saturn above the spin precession frequency of Jupiter, causing a Jupiter spin-orbit resonance...

  6. RESEARCH ARTICLE Broad-band versus narrow-band irradiance for estimating

    E-Print Network [OSTI]

    Klimley, A. Peter

    RESEARCH ARTICLE Broad-band versus narrow-band irradiance for estimating latitude by archival tags of irradiance to estimate the latitude of archival tags was evaluated. These tags are placed on fishes in order irradiance with and without a cosine collector and narrow-band irradiance of seven narrow bands with 50

  7. Regional characteristics, tilt domains, and extensional history...

    Open Energy Info (EERE)

    Report Number 303 DOI Not Provided Check for DOI availability: http:crossref.org Online Internet link for Regional characteristics, tilt domains, and extensional history of the...

  8. Large optics inspection, tilting, and washing stand

    DOE Patents [OSTI]

    Ayers, Marion Jay (Brentwood, CA); Ayers, Shannon Lee (Brentwood, CA)

    2010-08-24

    A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

  9. Large optics inspection, tilting, and washing stand

    DOE Patents [OSTI]

    Ayers, Marion Jay; Ayers, Shannon Lee

    2012-10-09

    A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

  10. DERIVED CATEGORIES AND TILTING BERNHARD KELLER

    E-Print Network [OSTI]

    Keller, Bernhard - Institut de Mathématiques de Jussieu, Université Paris 7

    DERIVED CATEGORIES AND TILTING BERNHARD KELLER Abstract. We review the basic definitions of derived categories and derived functors. We illustrate them on simple but non trivial examples. Then we explain Happel's theorem which states that each tilting triple yields an equiv- alence between derived categories

  11. Joule heating at high latitudes

    SciTech Connect (OSTI)

    Foster, J.C.; St.-Maurice, J.; Abreu, V.J.

    1983-06-01

    High latitude Joule heating has been calculated from simultaneous observations of the electric field magnitude and the Pedersen conductivity calculated from individual measurements of the ion drift velocity and particle precipitation observed over the lifetime of the AE-C satellite. The data were sorted by latitude, local time, hemisphere, season, and Kp index and separate averages of the electric field magnitude, Pedersen conductivity and Joule heating was prepared. Conductivities produced by an averaged seasonal solar illumination were included with those calculated from the particle precipitation. We found that high-latitude Joule heating occurs in a roughly oval pattern and consists of three distinct heating regions: the dayside cleft, the region of sunward convection at dawn and dusk, and the midnight sector. On the average, heating in the cleft and dawn-dusk regions contributes the largest heat input. There is no apparent difference between hemispheres for similar seasons. Hemisphere averaged Joule heating at equinox amounts to approximately 25 GW for Kp = 1 conditions, 85G GW for Kp = 4, and varies linearly as a function of Kp. The Joule heat input is 50% greater during the summer than during winter primarily due to the increased conductivity caused by solar production.

  12. Bhutan Solar Resources - Datasets - OpenEI Datasets

    Open Energy Info (EERE)

    Bhutan Solar Resources GIS data for Bhutan's direct normal irradiance (DNI), global horizontal irradianc, and latitude tilt. Data and Resources Bhutan Direct normal irradianceZIP...

  13. Global General Relativistic MHD Simulation of a Tilted Black-Hole Accretion Disk

    E-Print Network [OSTI]

    Fragile, P Chris; Anninos, Peter; Salmonson, Jay D

    2007-01-01

    This paper presents a continuation of our efforts to numerically study accretion disks that are misaligned (tilted) with respect to the rotation axis of a Kerr black hole. Here we present results of a global numerical simulation which fully incorporates the effects of the black hole spacetime as well as magnetorotational turbulence that is the primary source of angular momentum transport in the flow. This simulation shows dramatic differences from comparable simulations of untilted disks. Accretion onto the hole occurs predominantly through two opposing plunging streams that start from high latitudes with respect to both the black-hole and disk midplanes. This is due to the aspherical nature of the gravitational spacetime around the rotating black hole. These plunging streams start from a larger radius than would be expected for an untilted disk. In this regard the tilted black hole effectively acts like an untilted black hole of lesser spin. Throughout the duration of the simulation, the main body of the dis...

  14. 3, 10811107, 2003 Mid-latitude ozone

    E-Print Network [OSTI]

    Boyer, Edmond

    ACPD 3, 1081­1107, 2003 Mid-latitude ozone changes in a 3D CTM M. P. Chipperfield Title Page-dimensional model study of long-term mid-high latitude lower stratosphere ozone changes M. P. Chipperfield School­1107, 2003 Mid-latitude ozone changes in a 3D CTM M. P. Chipperfield Title Page Abstract Introduction

  15. Tilt assembly for tracking solar collector assembly

    DOE Patents [OSTI]

    Almy, Charles; Peurach, John; Sandler, Reuben

    2012-01-24

    A tilt assembly is used with a solar collector assembly of the type comprising a frame, supporting a solar collector, for movement about a tilt axis by pivoting a drive element between first and second orientations. The tilt assembly comprises a drive element coupler connected to the drive element and a driver, the driver comprising a drive frame, a drive arm and a drive arm driver. The drive arm is mounted to the drive frame for pivotal movement about a drive arm axis. Movement on the drive arm mimics movement of the drive element. Drive element couplers can extend in opposite directions from the outer portion of the drive arm, whereby the assembly can be used between adjacent solar collector assemblies in a row of solar collector assemblies.

  16. Tilting at MEMS Windmills for Energy Harvesting?

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    Tilting at MEMS Windmills for Energy Harvesting? Bill Schweber - February 19, 2015 MEMS and Development (yes, it was print), I saw the story "Micro-Windmills: From Lab to Market" on MEMS devices whichMEMS Technologies, a Taiwan-based company. Figure 1: The nickel-based MEMS micro-windmill can be bulk

  17. The cost of noise reduction in commercial tilt rotor aircraft

    E-Print Network [OSTI]

    Faulkner, Henry B.

    1974-01-01

    The relationship between direct operating cost and departure noise annoyance was developed for commercial tilt rotor aircraft. This was accomplished by generating a series of tilt rotor aircraft designs to meet various ...

  18. Nanoscale quantification of octahedral tilts in perovskite films

    E-Print Network [OSTI]

    Hwang, Jinwoo; Zhang, Jack; Son, Junwoo; Stemmer, Susanne

    2012-01-01

    tilts in ultrathin perovskite ?lms despite large unit cells,of octahedral tilts in perovskite films Jinwoo Hwang, a)BO 6 octahe- dra in perovskite unit cells (general formula

  19. The Role of Bilayer Tilt Difference in Equilibrium Membrane Shapes

    E-Print Network [OSTI]

    Nelson, Philip

    The Role of Bilayer Tilt Difference in Equilibrium Membrane Shapes Udo Seifert 1 ; Julian Shillcock into the elastic theory of tilted fluid membranes. It can drive an instability of the flat phase; it also provides to order. In analogy to smectic liquid crystals, one expects a soft tilt degree of freedom to ap­ pear

  20. Prediction of tilted capillary barrier performance

    SciTech Connect (OSTI)

    Webb, S.W.; McCord, J.T.; Dwyer, S.F.

    1997-04-01

    Capillary barriers, consisting of tilted fine-over-coarse layers under unsaturated conditions, have been suggested as landfill covers to divert water infiltration away from sensitive underground regions, especially for arid and semi-arid regions. The Hydrological Evaluation of Landfill Performance (HELP) computer code is an evaluation tool for landfill covers used by designers and regulators. HELP is a quasi-two-dimensional model that predicts moisture movement into and through the underground soil and waste layers. Processes modeled within HELP include precipitation, runoff, evapotranspiration, unsaturated vertical drainage, saturated lateral drainage, and leakage through liners. Unfortunately, multidimensional unsaturated flow phenomena that are necessary for evaluating tilted capillary barriers are not included in HELP. Differences between the predictions of the HELP and those from a multidimensional unsaturated flow code are presented to assess the two different approaches. Comparisons are presented for the landfill covers including capillary barrier configurations at the Alternative Landfill Cover Demonstration (ALCD) being conducted at Sandia.

  1. Notes 16. Analysis of tilting pad bearings 

    E-Print Network [OSTI]

    San Andres, Luis

    2010-01-01

    affecting tilting pad bearing force coefficients include elastic deformation of the bearing pads and pivots, thermal effects affecting the lubricant viscosity and film clearance, etc. [2,3]. ? Pad Pivot Journal Y X ? Journal speed NOTES 16... is assumed rigid. Journal motion perturbation analysis The bearing supports a static load with components { } YoXo WW , . At speed ?, the static load determines operation with the journal at its static equilibrium position ( YoXo ee ,). At equilibrium...

  2. Global General Relativistic MHD Simulation of a Tilted Black-Hole Accretion Disk

    E-Print Network [OSTI]

    P. Chris Fragile; Omer M. Blaes; Peter Anninos; Jay D. Salmonson

    2007-06-28

    This paper presents a continuation of our efforts to numerically study accretion disks that are misaligned (tilted) with respect to the rotation axis of a Kerr black hole. Here we present results of a global numerical simulation which fully incorporates the effects of the black hole spacetime as well as magnetorotational turbulence that is the primary source of angular momentum transport in the flow. This simulation shows dramatic differences from comparable simulations of untilted disks. Accretion onto the hole occurs predominantly through two opposing plunging streams that start from high latitudes with respect to both the black-hole and disk midplanes. This is due to the aspherical nature of the gravitational spacetime around the rotating black hole. These plunging streams start from a larger radius than would be expected for an untilted disk. In this regard the tilted black hole effectively acts like an untilted black hole of lesser spin. Throughout the duration of the simulation, the main body of the disk remains tilted with respect to the symmetry plane of the black hole; thus there is no indication of a Bardeen-Petterson effect in the disk at large. The torque of the black hole instead principally causes a global precession of the main disk body. In this simulation the precession has a frequency of $3 (M_\\odot/M)$ Hz, a value consistent with many observed low-frequency quasi-periodic oscillations. However, this value is strongly dependent on the size of the disk, so this frequency may be expected to vary over a large range.

  3. Cell separation using tilted-angle standing surface acoustic waves

    E-Print Network [OSTI]

    Dao, Ming

    Cell separation using tilted-angle standing surface acoustic waves Xiaoyun Dinga,1 , Zhangli Pengb for studying cell properties, disease diagnostics, and therapeutics. Cell sorting by acoustic waves offers diagnostics. In this work, we introduce a unique configuration of tilted-angle standing surface acoustic waves

  4. TWOSIDED TILTING COMPLEXES FOR GREEN ORDERS AND BRAUER TREE ALGEBRAS

    E-Print Network [OSTI]

    Zimmermann, Alexander

    a perfect field k then there is a complete discrete valuation do* *main R with residue field k and a Green TWOSIDED TILTING COMPLEXES FOR GREEN ORDERS AND BRAUER TREE tilting complex between two Green o* *rders having the same structural data as they were defined

  5. TWOSIDED TILTING COMPLEXES FOR GREEN ORDERS AND BRAUER TREE ALGEBRAS

    E-Print Network [OSTI]

    Zimmermann, Alexander

    field k then there is a complete discrete valuation domain R with residue field k and a Green orderTWOSIDED TILTING COMPLEXES FOR GREEN ORDERS AND BRAUER TREE ALGEBRAS ALEXANDER ZIMMERMANN Abstract. We give an explicit twosided tilting complex between two Green orders having the same structural data

  6. TILT POUR TRIALS AND ANALYSIS Bob Bryant1

    E-Print Network [OSTI]

    Beckermann, Christoph

    1 Matrix Metals Keokuk Facility (Keokuk Steel Castings) Keokuk, Iowa 52632 2 Department casting trials. In the tilting molds used for these casting trials, metal is initially poured metal from the holding basin into the casting cavity. Filling a casting cavity through tilting rather

  7. The Role of Bilayer Tilt Difference in Equilibrium Membrane Shapes

    E-Print Network [OSTI]

    Nelson, Philip

    The Role of Bilayer Tilt Difference in Equilibrium Membrane Shapes Udo Seifert 1 , Julian Shillcock difference introduces a length scale into the elastic theory of tilted fluid membranes. It can drive of mem­ branes as their hydrocarbon chains begin to order. In analogy to smectic liquid crystals, one

  8. IRRADIATION EXPERIMENTS &

    E-Print Network [OSTI]

    McDonald, Kirk

    IRRADIATION EXPERIMENTS & FACILITIES AT BNL: BLIP & NSLS II Peter Wanderer Superconducting MagnetV). Simultaneous irradiation and isotope production by increasing beam energy, placing irradiation target ahead of isotope production target · 117 Mev 140, 160, 180, 202 MeV · Irradiation at room temperature Alternative

  9. Future asymptotics of tilted Bianchi type II cosmologies

    E-Print Network [OSTI]

    Sigbjorn Hervik; Woei Chet Lim; Patrik Sandin; Claes Uggla

    2010-04-21

    In this paper we study the future asymptotics of spatially homogeneous Bianchi type II cosmologies with a tilted perfect fluid with a linear equation of state. By means of Hamiltonian methods we first find a monotone function for a special tilted case, which subsequently allows us to construct a new set of monotone functions for the general tilted type II cosmologies. In the context of a new partially gauge invariant dynamical system, this then leads to a proof for a theorem that for the first time gives a complete description of the future asymptotic states of the general tilted Bianchi type II models. The generality of our arguments suggests how one can produce monotone functions that are useful for determining the asymptotics of other tilted perfect fluid cosmologies, as well as for other sources.

  10. Concrete Tilt-up Construction on the Farm. 

    E-Print Network [OSTI]

    Hobgood, Price; Kunze, Otto R.

    1957-01-01

    with satisfactory results contained a minimum of five sacks of cement per cubic yard of mix. Clean, hard and well-graded aggregate was used. Reinforcing steel was placed in every panel to insure adequate strength and stability. The tilting bolts at the top... to the panel. Nuts were placed on the bolts. After the tilting frame was removed, the metal stra~s were wired to the lower tilting bolts to make panel more secure. , per 'aces 10\\I'S STABILIZING THE WALL PANELS ! the The panels were plumbed and aligned...

  11. Reconciliation of local and long range tilt correlations in underdoped...

    Office of Scientific and Technical Information (OSTI)

    powder diffraction and inelastic neutron scattering (INS) approaches. Long-range and static CuO tilt order with orthogonally inequivalent Cu-O bonds in the CuO planes in...

  12. Revisiting the question: Does high-latitude solar activity lead low-latitude solar activity in time phase?

    SciTech Connect (OSTI)

    Kong, D. F.; Qu, Z. N.; Guo, Q. L.

    2014-05-01

    Cross-correlation analysis and wavelet transform methods are used to investigate whether high-latitude solar activity leads low-latitude solar activity in time phase or not, using the data of the Carte Synoptique solar filaments archive from 1919 March to 1989 December. From the cross-correlation analysis, high-latitude solar filaments have a time lead of 12 Carrington solar rotations with respect to low-latitude ones. Both the cross-wavelet transform and wavelet coherence indicate that high-latitude solar filaments lead low-latitude ones in time phase. Furthermore, low-latitude solar activity is better correlated with high-latitude solar activity of the previous cycle than with that of the following cycle, which is statistically significant. Thus, the present study confirms that high-latitude solar activity in the polar regions is indeed better correlated with the low-latitude solar activity of the following cycle than with that of the previous cycle, namely, leading in time phase.

  13. Method to fabricate a tilted logpile photonic crystal

    DOE Patents [OSTI]

    Williams, John D. (Albuquerque, NM); Sweatt, William C. (Albuquerque, NM)

    2010-10-26

    A method to fabricate a tilted logpile photonic crystal requires only two lithographic exposures and does not require mask repositioning between exposures. The mask and photoresist-coated substrate are spaced a fixed and constant distance apart using a spacer and the stack is clamped together. The stack is then tilted at a crystallographic symmetry angle (e.g., 45 degrees) relative to the X-ray beam and rotated about the surface normal until the mask is aligned with the X-ray beam. The stack is then rotated in plane by a small stitching angle and exposed to the X-ray beam to pattern the first half of the structure. The stack is then rotated by 180.degree. about the normal and a second exposure patterns the remaining half of the structure. The method can use commercially available DXRL scanner technology and LIGA processes to fabricate large-area, high-quality tilted logpile photonic crystals.

  14. Laser Guide Star Adaptive Optics without Tip-tilt

    E-Print Network [OSTI]

    R. Davies; S. Rabien; C. Lidman; M. Le Louarn; M. Kasper; N. M. Forster Schreiber; V. Roccatagliata; N. Ageorges; P. Amico; C. Dumas; F. Mannucci

    2008-01-24

    Adaptive optics (AO) systems allow a telescope to reach its diffraction limit at near infrared wavelengths. But to achieve this, a bright natural guide star (NGS) is needed for the wavefront sensing, severely limiting the fraction of the sky over which AO can be used. To some extent this can be overcome with a laser guide star (LGS). While the laser can be pointed anywhere in the sky, one still needs to have a natural star, albeit fainter, reasonably close to correct the image motion (tip-tilt) to which laser guide stars are insensitive. There are in fact many astronomical targets without suitable tip-tilt stars, but for which the enhanced resolution obtained with the Laser Guide Star Facility (LGSF) would still be very beneficial. This article explores what adaptive optics performance one might expect if one dispenses with the tip-tilt star, and in what situations this mode of observing might be needed.

  15. Anisotropic cosmology and inflation from tilted Bianchi IX model

    E-Print Network [OSTI]

    Sundell, Peter

    2015-01-01

    The dynamics of the tilted Bianchi IX cosmological models are explored allowing energy flux in the source fluid. The equation of state and the tilt angle of the fluid are the two free parameters and the shear, the vorticity and the curvature of the spacetime span a three-dimensional phase space that contains seven fixed points. One of them is an attractor that inflates the universe anisotropically, thus providing a counter example to the cosmic no-hair conjecture. Also, an example of a realistic though fine-tuned cosmology is presented wherein the rotation can grow significant towards the present epoch but the shear stays within the observational bounds.

  16. Anisotropic cosmology and inflation from tilted Bianchi IX model

    E-Print Network [OSTI]

    Peter Sundell; Tomi Koivisto

    2015-06-15

    The dynamics of the tilted Bianchi IX cosmological models are explored allowing energy flux in the source fluid. The equation of state and the tilt angle of the fluid are the two free parameters and the shear, the vorticity and the curvature of the spacetime span a three-dimensional phase space that contains seven fixed points. One of them is an attractor that inflates the universe anisotropically, thus providing a counter example to the cosmic no-hair conjecture. Also, an example of a realistic though fine-tuned cosmology is presented wherein the rotation can grow significant towards the present epoch but the shear stays within the observational bounds.

  17. Gating-by-tilt of mechanosensitive membrane channels

    E-Print Network [OSTI]

    Matthew S. Turner; Pierre Sens

    2003-11-25

    We propose an alternative mechanism for the gating of biological membrane channels in response to membrane tension that involves a change in the slope of the membrane near the channel. Under biological membrane tensions we show that the energy difference between the closed (tilted) and open (untilted) states can far exceed kBT and is comparable to what is available under simple ilational gating. Recent experiments demonstrate that membrane leaflet asymmetries (spontaneous curvature) can strong effect the gating of some channels. Such a phenomenon would be more easy to explain under gating-by-tilt, given its novel intrinsic sensitivity to such asymmetry.

  18. Relationship between eddydriven jet latitude and width J. Kidston1

    E-Print Network [OSTI]

    Kidston, Joseph

    correlation between the latitude and the width of the eddydriven jet stream, and we argue that barotropic. Here we suggest that similar processes may be important for the tropospheric jet stream whenRelationship between eddydriven jet latitude and width J. Kidston1 and G. K. Vallis1 Received 26

  19. Summertime total ozone variations over middle and polar latitudes

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Summertime total ozone variations over middle and polar latitudes Article Published Version Fioletov, V. E. and Shepherd, T. G. (2005) Summertime total ozone variations over middle and polar's research outputs online #12;Summertime total ozone variations over middle and polar latitudes Vitali E

  20. Tilted Baroclinic Tidal Vortices MIGUEL CANALS AND GENO PAWLAK

    E-Print Network [OSTI]

    MacCready, Parker

    Tilted Baroclinic Tidal Vortices MIGUEL CANALS AND GENO PAWLAK Department of Ocean and Resources coherence. It is suggested that this may lead to a conversion of potential energy into kinetic energy. 1 mixing of coastal waters (Mul- ler and Garrett 2003). Of particular importance is the tidally driven case

  1. Reconciliation of local and long-range tilt correlations in underdoped...

    Office of Scientific and Technical Information (OSTI)

    and long-range tilt correlations in underdoped La2-xBaxCuO4(0 x 0.155) A long standing puzzle regarding the disparity of local and long range CuO octahedral tilt...

  2. The cost of noise reduction for departure and arrival operations of commercial tilt rotor aircraft

    E-Print Network [OSTI]

    Faulkner, Henry B.

    1976-01-01

    The relationship between direct operating cost (DOC) and noise annoyance due to a departure and an arrival operation was developed for commercial tilt rotor aircraft. This was accomplished by generating a series of tilt ...

  3. Rotordynamic and thermal analyses of compliant flexure pivot tilting pad gas bearings 

    E-Print Network [OSTI]

    Sim, Kyu-Ho

    2009-05-15

    Rotordynamic and thermal analyses of compliant flexure pivot tilting pad gas bearings were performed. First, compliant flexure pivot tilting pad gas bearings with pad radial compliance (CFTPBs) were introduced and designed for high-speed oil...

  4. Generating f0 contours for speech synthesis using the tilt intonation theory. 

    E-Print Network [OSTI]

    Dusterhoff, Kurt E; Black, Alan W

    1997-01-01

    This paper presents a method for generating f0 contours for a speech synthesis system using the Tilt intonation theory.

  5. Modeling Flow Past a Tilted Vena Cava Filter

    SciTech Connect (OSTI)

    Singer, M A; Wang, S L

    2009-06-29

    Inferior vena cava filters are medical devices used to prevent pulmonary embolism (PE) from deep vein thrombosis. In particular, retrievable filters are well-suited for patients who are unresponsive to anticoagulation therapy and whose risk of PE decreased with time. The goal of this work is to use computational fluid dynamics to evaluate the flow past an unoccluded and partially occluded Celect inferior vena cava filter. In particular, the hemodynamic response to thrombus volume and filter tilt is examined, and the results are compared with flow conditions that are known to be thrombogenic. A computer model of the filter inside a model vena cava is constructed using high resolution digital photographs and methods of computer aided design. The models are parameterized using the Overture software framework, and a collection of overlapping grids is constructed to discretize the flow domain. The incompressible Navier-Stokes equations are solved, and the characteristics of the flow (i.e., velocity contours and wall shear stresses) are computed. The volume of stagnant and recirculating flow increases with thrombus volume. In addition, as the filter increases tilt, the cava wall adjacent to the tilted filter is subjected to low velocity flow that gives rise to regions of low wall shear stress. The results demonstrate the ease of IVC filter modeling with the Overture software framework. Flow conditions caused by the tilted Celect filter may elevate the risk of intrafilter thrombosis and facilitate vascular remodeling. This latter condition also increases the risk of penetration and potential incorporation of the hook of the filter into the vena caval wall, thereby complicating filter retrieval. Consequently, severe tilt at the time of filter deployment may warrant early clinical intervention.

  6. On the first Hochschild cohomology group of a cluster-tilted algebra

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    On the first Hochschild cohomology group of a cluster-tilted algebra Ibrahim Assem, Mar´ia Julia Redondo and Ralf Schiffler Abstract Given a cluster-tilted algebra B, we study its first Hochschild cohomol- ogy group HH1 (B) with coefficients in the B-B-bimodule B. If C is a tilted algebra such that B

  7. Dynamic Model and Control of a New Quadrotor Unmanned Aerial Vehicle with Tilt-Wing

    E-Print Network [OSTI]

    Yanikoglu, Berrin

    Dynamic Model and Control of a New Quadrotor Unmanned Aerial Vehicle with Tilt-Wing Mechanism Kaan, LQR, Quadrotor, Tilt-wing, VTOL. I. INTRODUCTION Unmanned aerial vehicles (UAV) designed for various of a new tilt-wing aerial vehicle (SUAVi: Sabanci University Unmanned Aerial Vehicle) that is capable

  8. Isentropic diagnostics of mid-latitude circulation and transport

    E-Print Network [OSTI]

    Koh, Tieh-Yong, 1972-

    2001-01-01

    This thesis examines the mid-latitude circulation and tracer transport using zonal average isentropic diagnostics. The Underworld (i.e. the region roughly below the 300K-isentrope) is targeted by our research. Currently, ...

  9. A High Resolution Micro-Electro-Mechanical Resonant Tilt Sensor

    E-Print Network [OSTI]

    Zou, Xudong; Thiruvenkatanathan, Pradyumna; Seshia, Ashwin A.

    2014-10-12

    Solid-State Sensors, Actuators and Microsystems Conference, 15th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers 2009), 2009, 300-3. [15] J. Ho, K. Chang Jin, K. Seong Ho, An optimized MEMS-based electrolytic... reported to date in such tilt sensors. A few methods that have gained visibility in recent years include fibre-optic interferometric displacement sensing, variable resistance or impedance based detection, electrolytic sensing, thermal-convection based...

  10. EIS-0039: Motor Gasoline Deregulation and the Gasoline Tilt

    Broader source: Energy.gov [DOE]

    The Economic Regulatory Administration developed this EIS to evaluate the environmental impacts, including social and economic impacts, that may result from either of two proposed regulatory changes: (1) the exemption of motor gasoline from the Department of Energy's Mandatory Petroleum Price and Allocation Regulations, and (2) the adoption of the gasoline tilt, a proposed regulation that would allow refiners to recover an additional amount of their total increased costs on gasoline.

  11. Splay and tilt energy of bipolar lipid membranes

    E-Print Network [OSTI]

    Timur R. Galimzyanov; Peter I. Kuzmin; Peter Pohl; Sergey A. Akimov

    2014-12-28

    Archaea organisms are able to survive in extremely aggressive environment. It is thought that such resistance, at least, in part is sustained by unique properties of archaea membrane. The membrane consists of so called bolalipids, which has two polar heads joined by two hydrocarbon chains. Thus bolalipids can exist in two conformations: i) polar heads are located at different sides of bolalipid layer, so called, O-shape; ii) polar heads are located at the same side of the layer, so called, U-shape. Both polar heads and chains are chemically different from those for conventional lipids. In the present study we develop basis for theory of elasticity of bolalipid membranes. Deformations of splay, tilt and Gaussian curvature are considered. We show that energetic contributions of tilt deformation from two surfaces of bolalipid layer are additive, as well as Gaussian curvature, while splay deformations yield a cross-term. The presence of U-shapes is taken into account in terms of the layer spontaneous curvature. Estimation of tilt modulus and possible experiments allowing to measure splay moduli are described.

  12. AN ABSENCE OF FAST RADIO BURSTS AT INTERMEDIATE GALACTIC LATITUDES

    SciTech Connect (OSTI)

    Petroff, E.; Van Straten, W.; Bailes, M.; Barr, E. D.; Coster, P.; Flynn, C.; Keane, E. F. [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, P.O. Box 218, Hawthorn, VIC 3122 (Australia); Johnston, S. [CSIRO Astronomy and Space Science, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710 (Australia); Bates, S. D.; Keith, M. J.; Kramer, M.; Stappers, B. W. [Jodrell Bank Centre for Astrophysics, University of Manchester, Alan Turing Building, Oxford Road, Manchester M13 9PL (United Kingdom); Bhat, N. D. R. [ARC Centre of Excellence for All-sky Astrophysics (CAASTRO), 44 Rosehill Street, Redfern, NSW 2016 (Australia); Burgay, M.; Possenti, A.; Tiburzi, C. [INAF—Osservatorio Astronomico di Cagliari, Via della Scienza, I-09047 Selargius (Italy); Burke-Spolaor, S. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91104 (United States); Champion, D.; Ng, C. [Max Planck Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany); Levin, L., E-mail: epetroff@astro.swin.edu.au [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States); and others

    2014-07-10

    Fast radio bursts (FRBs) are an emerging class of bright, highly dispersed radio pulses. Recent work by Thornton et al. has revealed a population of FRBs in the High Time Resolution Universe (HTRU) survey at high Galactic latitudes. A variety of progenitors have been proposed, including cataclysmic events at cosmological distances, Galactic flare stars, and terrestrial radio frequency interference. Here we report on a search for FRBs at intermediate Galactic latitudes (–15° latitudes. A revised rate estimate or another strong and heretofore unknown selection effect in Galactic latitude would provide closer agreement between the surveys' detection rates. The dearth of detections at low Galactic latitude disfavors a Galactic origin for these bursts.

  13. THEORY OF SOLAR MERIDIONAL CIRCULATION AT HIGH LATITUDES

    SciTech Connect (OSTI)

    Dikpati, Mausumi; Gilman, Peter A. E-mail: gilman@ucar.edu

    2012-02-10

    We build a hydrodynamic model for computing and understanding the Sun's large-scale high-latitude flows, including Coriolis forces, turbulent diffusion of momentum, and gyroscopic pumping. Side boundaries of the spherical 'polar cap', our computational domain, are located at latitudes {>=} 60 Degree-Sign . Implementing observed low-latitude flows as side boundary conditions, we solve the flow equations for a Cartesian analog of the polar cap. The key parameter that determines whether there are nodes in the high-latitude meridional flow is {epsilon} = 2{Omega}n{pi}H{sup 2}/{nu}, where {Omega} is the interior rotation rate, n is the radial wavenumber of the meridional flow, H is the depth of the convection zone, and {nu} is the turbulent viscosity. The smaller the {epsilon} (larger turbulent viscosity), the fewer the number of nodes in high latitudes. For all latitudes within the polar cap, we find three nodes for {nu} = 10{sup 12} cm{sup 2} s{sup -1}, two for 10{sup 13}, and one or none for 10{sup 15} or higher. For {nu} near 10{sup 14} our model exhibits 'node merging': as the meridional flow speed is increased, two nodes cancel each other, leaving no nodes. On the other hand, for fixed flow speed at the boundary, as {nu} is increased the poleward-most node migrates to the pole and disappears, ultimately for high enough {nu} leaving no nodes. These results suggest that primary poleward surface meridional flow can extend from 60 Degree-Sign to the pole either by node merging or by node migration and disappearance.

  14. Tilt and Rotation Angles of a Transmembrane Model Peptide as Studied by Fluorescence Spectroscopy

    E-Print Network [OSTI]

    Gelb, Michael

    concentrations of cholesterol, small changes in tilt angle were observed as response to hydro- phobic mismatch). Similar results have been re- ported for other small natural membrane peptides

  15. Semi-empirical low-latitude ionospheric model

    SciTech Connect (OSTI)

    Anderson, D.N.; Mendillo, M.; Herniter, B.

    1987-04-01

    Since current empirical models specifying low-latitude electron-density profiles severely underestimate the daytime plasma scale height and total electron content (TEC) values, a semiempirical low-latitude ionospheric model (SLIM) was developed that is not only computationally fast, but also more realistic. Electron-density profiles (180-1800 km) are theoretically calculated as a function of latitude (every 2 deg between 24 N and 24 S dip latitude) and local time (every half hour, over 24 hours LT) by solving the time-dependent plasma-continuity equation. Using simple exponential functions, sets of coefficients themselves are easily stored. quickly retrieved and form the basis for a fast, portable, semi-empirical computer code. This paper describes briefly the input parameters used to theoretically calculate the profiles and the procedures used to generate the coefficients. The SLIM profiles are compared with the Chiu and Bent empirical models for equinox, solar maximum conditions, while calculated at 6300 A airglow intensities and TEC values are compared with available observations. The SLIM profiles, their coefficients, TEC and 6300 A airglow intensities are available in tabular and computer formats.

  16. Ozone Chemistry in the High-Latitude Boundary Layer

    E-Print Network [OSTI]

    Toohey, Darin W.

    Ozone Chemistry in the High-Latitude Boundary Layer Linnea Avallone Department of Atmospheric layer ozone loss phenomenon · In situ observations of BrO at Arctic sites · Preliminary results from Antarctic experiments in 2002 and 2004 #12;Brief History · Springtime ozone loss observed at many sites

  17. Holocene climate evolution in the high-latitude Southern Hemisphere

    E-Print Network [OSTI]

    Renssen, Hans

    temperature evolution during different seasons in the high-latitude Southern Hemisphere. We find in summer a thermal optimum in the mid- Holocene (6Á/3 ka BP), with temperatures locally 38C above the preindustrial insolation by 1 to 2 months owing to the thermal inertia of the system, and (2) the long memory

  18. Unified irradiance equations

    E-Print Network [OSTI]

    Preisendorfer, Rudolph W

    1957-01-01

    dealt vdth a pair of irradiance functions representing twoHjC^.n^)^ which i s the irradiance a t time t on a unit areaCalifornia UNIFIED IRRADIANCE EQUATIONS R. W. Preisendorfer

  19. Escape configuration lattice near the nematic-isotropic transition: Tilt analogue of blue phases

    E-Print Network [OSTI]

    Buddhapriya Chakrabarti; Yashodhan Hatwalne; N. V. Madhusudana

    2006-04-28

    We predict the possible existence of a new phase of liquid crystals near the nematic-isotropic ($ NI $) transition. This phase is an achiral, tilt-analogue of the blue phase and is composed of a lattice of {\\em double-tilt}, escape-configuration cylinders. We discuss the structure and the stability of this phase and provide an estimate of the lattice parameter.

  20. Changes in crystalline lens radii of curvature and lens tilt and decentration during dynamic accommodation in

    E-Print Network [OSTI]

    Glasser, Adrian

    Changes in crystalline lens radii of curvature and lens tilt and decentration during dynamic of Houston, College of Optometry, Houston, TX, USAAdrian Glasser Dynamic changes in crystalline lens radii accommodation, phakometry, tilt, decentration, crystalline, presbyopia Citation: Rosales, P., Wendt, M., Marcos

  1. Structure and Chemistry of Yttria-Stabilized Cubic-Zirconia Symmetric Tilt Grain Boundaries

    E-Print Network [OSTI]

    Pennycook, Steve

    Structure and Chemistry of Yttria-Stabilized Cubic-Zirconia Symmetric Tilt Grain Boundaries boundaries in yttria-stabilized cubic-zirconia, 5 (310) and near- 13 (510), are studied by Z [001] symmetric tilt grain boundaries in yttria-stabilized cubic-zirconia (YSZ). The grain boundaries

  2. Dominant dimensions, derived equivalences and tilting modules Hongxing Chen and Changchang Xi

    E-Print Network [OSTI]

    Xi, Changchang

    Dominant dimensions, derived equivalences and tilting modules Hongxing Chen and Changchang Xi by understanding this conjecture in the context of derived categories, we study dominant dimensions of algebras under derived equivalences induced by tilting modules, specifically, the infinity of dominant dimensions

  3. Learning from history: Adaptive calibration of 'tilting spine' fiber positioners

    E-Print Network [OSTI]

    Gilbert, James

    2015-01-01

    This paper discusses a new approach for determining the calibration parameters of independently-actuated optical fibers in multi-object astronomical fiber positioning systems. This work comes from the development of a new type of piezoelectric motor intended to enhance the 'tilting spine' fiber positioning technology originally created by the Australian Astronomical Observatory. Testing has shown that the motor's performance can vary depending on the fiber's location within its accessible field, meaning that an individual fiber is difficult calibrate with a one-time routine. Better performance has resulted from constantly updating calibration parameters based on the observed movements of the fiber during normal closed-loop positioning. Over time, location-specific historical data is amassed that can be used to better predict the results of a future fiber movement. This is similar to a technique previously proposed by the Australian Astronomical Observatory, but with the addition of location-specific learning....

  4. Bound Chains of Tilted Dipoles in Layered Systems

    E-Print Network [OSTI]

    A. G. Volosniev; J. R. Armstrong; D. V. Fedorov; A. S. Jensen; N. T. Zinner

    2012-03-01

    Ultracold polar molecules in multilayered systems have been experimentally realized very recently. While experiments study these systems almost exclusively through their chemical reactivity, the outlook for creating and manipulating exotic few- and many-body physics in dipolar systems is fascinating. Here we concentrate on few-body states in a multilayered setup. We exploit the geometry of the interlayer potential to calculate the two- and three-body chains with one molecule in each layer. The focus is on dipoles that are aligned at some angle with respect to the layer planes by means of an external eletric field. The binding energy and the spatial structure of the bound states are studied in several different ways using analytical approaches. The results are compared to stochastic variational calculations and very good agreement is found. We conclude that approximations based on harmonic oscillator potentials are accurate even for tilted dipoles when the geometry of the potential landscape is taken into account.

  5. Microelectromechanical apparatus for elevating and tilting a platform

    DOE Patents [OSTI]

    Miller, Samuel Lee; McWhorter, Paul Jackson; Rodgers, Murray Steven; Sniegowski, Jeffry J.; Barnes, Stephen M.

    2004-07-06

    A microelectromechanical (MEM) apparatus is disclosed which has a platform that can be elevated above a substrate and tilted at an arbitrary angle using a plurality of flexible members which support the platform and control its movement. Each flexible member is further controlled by one or more MEM actuators which act to bend the flexible member. The MEM actuators can be electrostatic comb actuators or vertical zip actuators, or a combination thereof. The MEM apparatus can include a mirror coating to form a programmable mirror for redirecting or switching one or more light beams for use in a projection display. The MEM apparatus with-the mirror coating also has applications for switching light beams between optical fibers for use in a local area fiber optic network, or for use in fiber optic telecommunications or data communications systems.

  6. Microelectromechanical apparatus for elevating and tilting a platform

    DOE Patents [OSTI]

    Miller, Samuel Lee (Albuquerque, NM); McWhorter, Paul Jackson (Albuquerque, NM); Rodgers, Murray Steven (Albuquerque, NM); Sniegowski, Jeffry J. (Edgewood, NM); Barnes, Stephen M. (Albuquerque, NM)

    2003-04-08

    A microelectromechanical (MEM) apparatus is disclosed which has a platform that can be elevated above a substrate and tilted at an arbitrary angle using a plurality of flexible members which support the platform and control its movement. Each flexible member is further controlled by one or more MEM actuators which act to bend the flexible member. The MEM actuators can be electrostatic comb actuators or vertical zip actuators, or a combination thereof. The MEM apparatus can include a mirror coating to form a programmable mirror for redirecting or switching one or more light beams for use in a projection display. The MEM apparatus with the mirror coating also has applications for switching light beams between optical fibers for use in a local area fiber optic network, or for use in fiber optic telecommunications or data communications systems.

  7. Confined Dirac Particles in Constant and Tilted Magnetic Field

    E-Print Network [OSTI]

    Abdulaziz D. Alhaidari; Hocine Bahlouli; Ahmed Jellal

    2012-02-23

    We study the confinement of charged Dirac particles in 3+1 space-time due to the presence of a constant and tilted magnetic field. We focus on the nature of the solutions of the Dirac equation and on how they depend on the choice of vector potential that gives rise to the magnetic field. In particular, we select a "Landau gauge" such that the momentum is conserved along the direction of the vector potential yielding spinor wavefunctions, which are localized in the plane containing the magnetic field and normal to the vector potential. These wave functions are expressed in terms of the Hermite polynomials. We point out the relevance of these findings to the relativistic quantum Hall effect and compare with the results obtained for a constant magnetic field normal to the plane in 2+1 dimensions.

  8. Atmospheric p CO 2 sensitivity to the solubility pump: Role of the low-latitude ocean

    E-Print Network [OSTI]

    DeVries, T.; Primeau, F.

    2009-01-01

    causes an anomalous outgassing of CO 2 at high latitudes.poleward causes anomalous outgassing in the high latitudes.This outgassing represents a negative feedback that tends to

  9. Cellular structures in the high-latitude thermosphere

    SciTech Connect (OSTI)

    Crowley, G. [Johns Hopkins Univ. Laurel, MD (United States)] [Johns Hopkins Univ. Laurel, MD (United States); Schoendorf, J.; Roble, R.G. [NCAR, Boulder, CO (United States)] [and others] [NCAR, Boulder, CO (United States); and others

    1996-01-01

    An organized density (and pressure) structure was recently discovered in the neutral thermosphere at high-latitudes. The structure consists of two to four high- and low-density regions having diameters of 1000 to 2000 km. The density in each region is enhanced or depleted from the hemispheric average by up to 30%. The structure is thus a significant feature of the near-Earth space environment at high-latitudes. The authors refer to each distinct region of enhanced or depleted density as a density {open_quotes}cell.{close_quotes} The cells extend upward from about 120 km into the upper thermosphere, and once formed they remain approximately fixed with respect to the geomagnetic pole. A parametric study of the density cell morphology for different magnetic activity levels is described for equinox solar minimum using the National Center for Atmospheric Research thermosphere ionosphere general circulation model (NCAR model). The TIGCM simulations were used to predict the large density perturbations observed by the S85-1 satellite in a circular sun-synchronous orbit near 200 km altitudes. The most obvious manifestations of the cells was the presence of density peaks located near 70{degrees}{Lambda} on the dayside and nightside, and a density minimum near the magnetic pole. Since high-latitude densities are generally expected to increase during magnetic activity, the low densities over the pole are perhaps the most interesting feature of the cell structure discussed here. The satellite data confirm the existence of the cellular structure over a range of magnetic activity levels. The discovery of the cells is important because the structure provides a unifying framework for the analysis and interpretation of high-latitude data from both past and future experiments. The cells result from various forms of coupling between the ionosphere and thermosphere. The cell formation is quantitatively consistent with concepts from dynamic meteorology. 34 refs., 11 figs.

  10. WIND-DRIVEN NEAR INERTIAL OCEAN RESPONSE AND MIXING AT THE CRITICAL LATITUDE 

    E-Print Network [OSTI]

    Zhang, Xiaoqian

    2010-07-14

    ? latitude. Near 30? latitude, the maximum oceanic response to sea breeze moves offshore slowly because of the near-zero group speed of Poincare waves at this latitude. The lateral energy flux convergence plus the energy input from the wind is maximum near...

  11. Seasonal persistence of northern low-and middle-latitude anomalies of ozone and

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Seasonal persistence of northern low- and middle-latitude anomalies of ozone and other trace gases) Seasonal persistence of northern low- and middle-latitude anomalies of ozone and other trace gases outputs online #12;Seasonal persistence of northern low- and middle-latitude anomalies of ozone and other

  12. Method for removing tilt control in adaptive optics systems

    DOE Patents [OSTI]

    Salmon, J.T.

    1998-04-28

    A new adaptive optics system and method of operation are disclosed, whereby the method removes tilt control, and includes the steps of using a steering mirror to steer a wavefront in the desired direction, for aiming an impinging aberrated light beam in the direction of a deformable mirror. The deformable mirror has its surface deformed selectively by means of a plurality of actuators, and compensates, at least partially, for existing aberrations in the light beam. The light beam is split into an output beam and a sample beam, and the sample beam is sampled using a wavefront sensor. The sampled signals are converted into corresponding electrical signals for driving a controller, which, in turn, drives the deformable mirror in a feedback loop in response to the sampled signals, for compensating for aberrations in the wavefront. To this purpose, a displacement error (gradient) of the wavefront is measured, and adjusted by a modified gain matrix, which satisfies the following equation: G{prime} = (I{minus}X(X{sup T} X){sup {minus}1}X{sup T})G(I{minus}A). 3 figs.

  13. Method for removing tilt control in adaptive optics systems

    DOE Patents [OSTI]

    Salmon, Joseph Thaddeus (Livermore, CA)

    1998-01-01

    A new adaptive optics system and method of operation, whereby the method removes tilt control, and includes the steps of using a steering mirror to steer a wavefront in the desired direction, for aiming an impinging aberrated light beam in the direction of a deformable mirror. The deformable mirror has its surface deformed selectively by means of a plurality of actuators, and compensates, at least partially, for existing aberrations in the light beam. The light beam is split into an output beam and a sample beam, and the sample beam is sampled using a wavefront sensor. The sampled signals are converted into corresponding electrical signals for driving a controller, which, in turn, drives the deformable mirror in a feedback loop in response to the sampled signals, for compensating for aberrations in the wavefront. To this purpose, a displacement error (gradient) of the wavefront is measured, and adjusted by a modified gain matrix, which satisfies the following equation: G'=(I-X(X.sup.T X).sup.-1 X.sup.T)G(I-A)

  14. Precision tip-tilt-piston actuator that provides exact constraint

    DOE Patents [OSTI]

    Hale, Layton C. (Livermore, CA)

    1999-01-01

    A precision device which can precisely actuate three degrees of freedom of an optic mount, commonly referred to as tip, tilt, and piston. The device consists of three identical flexure mechanisms, an optic mount to be supported and positioned, a structure that supports the flexure mechanisms, and three commercially available linear actuators. The advantages of the precision device is in the arrangement of the constraints offered by the flexure mechanism and not in the particular design of the flexure mechanisms, as other types of mechanisms could be substituted. Each flexure mechanism constrains two degrees of freedom in the plane of the mechanisms and one direction is actuated. All other degrees of freedom are free to move within the range of flexure mechanisms. Typically, three flexure mechanisms are equally spaced in angle about to optic mount and arranged so that each actuated degree of freedom is perpendicular to the plane formed by the optic mount. This arrangement exactly constrains the optic mount and allows arbitrary actuated movement of the plane within the range of the flexure mechanisms. Each flexure mechanism provides a mechanical advantage, typically on the order of 5:1, between the commercially available actuator and the functional point on the optic mount. This improves resolution by the same ratio and stiffness by the square of the ratio.

  15. Measurements of static loading characteristics of a Flexurepivot Tilt Pad Hydrodynamic Bearing 

    E-Print Network [OSTI]

    Walton, Nicholas Van Edward

    1995-01-01

    An experimental investigation examining the static loading characteristics of a four-pad, KMC FLEXUREPIVOT Tilt Pad Hydrodynamic Bearing is presented. Tests are conducted on the TRACE Fluid Film Bearing Element Test Rig for journal speeds ranging...

  16. The effects of motion experience on reflexive eye movements and dynamic tilt perception

    E-Print Network [OSTI]

    Ocampo, Robert P. (Robert Paul)

    2008-01-01

    Measured differences between human and primate VOR may derive from disparate experiences with psychophysical motion stimuli. To test this hypothesis, horizontal and torsional eye movements, as well as roll tilt perception, ...

  17. A Computational Model for Tilting Pad Journal Bearings with Pad Flexibility 

    E-Print Network [OSTI]

    Li, Yingkun

    2015-07-17

    Tilting pad journal bearings (TPJBs) supporting rotors for high performance turbomachinery have undergone steady design improvements to satisfy more stringent operating conditions that include large specific loads due to smaller footprints, and high...

  18. A Novel Computational Model for Tilting Pad Journal Bearings with Soft Pivot Stiffnesses 

    E-Print Network [OSTI]

    Tao, Yujiao 1988-

    2012-12-10

    A novel tilting pad journal bearing model including pivot flexibility as well as temporal fluid inertia effects on the thin film fluid flow aims to accurately predict the bearing forced performance. The predictive model also accounts for the thermal...

  19. Ionospheric slab thickness in middle and low latitudes

    SciTech Connect (OSTI)

    Davies, K.; Liu, X.M. (NOAA, Space Environment Laboratory, Boulder, CO (United States))

    1991-08-01

    The equivalent slab thickness of the ionosphere at 15 stations in middle and low latitudes was studied to determine its dependence on solar cycle and location. The data were grouped by season. The following are the major conclusions. There appears to be little or no geographical, or geomagnetic, dependence. The slab thickness varies approximately linearly with the 12-month smoothed values of the 10.7-cm solar radio flux. In middle latitudes the winter midnight thickness is essentially independent of the flux, whereas in summer and equinox the midnight thickness increases with increase of solar flux. The noon thickness increases with increase of solar flux in all seasons. The zero-order Fourier coeffficients for the diurnal curves at all 15 stations were expressed as linear functions of the 10.7-cm flux. The higher harmonic coefficients showed no appreciable dependence on solar flux. The pronounced predawn increase in slab thickness is caused by low values of the maximum electron density, not by increase of total electron content. 10 refs.

  20. Ionospheric manifestations of geomagnetic pulsations at high latitudes

    E-Print Network [OSTI]

    Lipko, Yu V; Rakhmatulin, R A; Lipko, Yu.V.

    2001-01-01

    In this paper the interrelation between geomagnetic pulsations and variations in frequency Doppler shift (Fd) of the ionosphere-reflected radio signal is under investigation. The experiment on simultaneous recording of Fd variations and geomagnetic pulsations was organised at high latitude station in Norilsk (geomagnetic latitude and longitude 64.2 N, 160.4 E, L=5.3) during Febrary-April of 1995-98. Thirty cases of simultaneous recording of duration from 10 min to two hour were analysed: 6 cases of simultaneous recording of variations Fd and regular geomagnetic pulsations Pc5; and 25 cases of recording of $f_d$ variations and irregular pulsations Pi2. On the basis of experimental results, the following conclusions have been drawn: a) Hydromagnetic waves in the range of regular Pc5 pulsations, when interacting with the ionospheric F2 layer, make the main contribution to short-period Fd variations. The possible mechanism of Fd variations are oscillations of electron density, associated with distribution of a hy...

  1. No evidence for the blue-tilted power spectrum of relic gravitational waves

    E-Print Network [OSTI]

    Qing-Guo Huang; Sai Wang

    2015-02-09

    In this paper, we constrain the tilt of the power spectrum of relic gravitational waves by combining the data from BICEP2/Keck array and Planck (BKP) and the Laser Interferometer Gravitational-Waves Observatory (LIGO). From the data of BKP B-modes, the constraint on the tensor tilt is $n_t=0.66^{+1.83}_{-1.44}$ at the $68%$ confidence level. By further adding the LIGO upper limit on the energy density of gravitational waves, the constraint becomes $n_t=-0.76^{+1.37}_{-0.52}$ at the $68%$ confidence level. We conclude that there is no evidence for a blue-tilted power spectrum of relic gravitational waves and either sign of the index of tensor power spectrum is compatible with the data.

  2. Design and initial characterization of a compact, ultra high vacuum compatible, low frequency, tilt accelerometer

    SciTech Connect (OSTI)

    O’Toole, A. E-mail: riccardo.desalvo@gmail.com; Peña Arellano, F. E.; Rodionov, A. V.; Kim, C.; Shaner, M.; Asadoor, M.; Sobacchi, E.; Dergachev, V.; DeSalvo, R. E-mail: riccardo.desalvo@gmail.com; Bhawal, A.; Gong, P.; Lottarini, A.; Minenkov, Y.; Murphy, C.

    2014-07-15

    A compact tilt accelerometer with high sensitivity at low frequency was designed to provide low frequency corrections for the feedback signal of the Advanced Laser Interferometer Gravitational Wave Observatory active seismic attenuation system. It has been developed using a Tungsten Carbide ceramic knife-edge hinge designed to avoid the mechanical 1/f noise believed to be intrinsic in polycrystalline metallic flexures. Design and construction details are presented; prototype data acquisition and control limitations are discussed. The instrument's characterization reported here shows that the hinge is compatible with being metal-hysteresis-free, and therefore also free of the 1/f noise generated by the dislocation Self-Organized Criticality in the metal. A tiltmeter of this kind will be effective to separate the ground tilt component from the signal of horizontal low frequency seismometers, and to correct the ill effects of microseismic tilt in advanced seismic attenuation systems.

  3. Blue-tilted Tensor Spectrum and Thermal History of the Universe

    E-Print Network [OSTI]

    Sachiko Kuroyanagi; Tomo Takahashi; Shuichiro Yokoyama

    2014-07-17

    We investigate constraints on the spectral index of primordial gravitational waves (GWs), paying particular attention to a blue-tilted spectrum. Such constraints can be used to test a certain class of models of the early Universe. We investigate observational bounds from LIGO+Virgo, pulsar timing and big bang nucleosynthesis, taking into account the suppression of the amplitude at high frequencies due to reheating after inflation and also late-time entropy production. Constraints on the spectral index are presented by changing values of parameters such as reheating temperatures and the amount of entropy produced at late time. We also consider constraints under the general modeling approach which can approximately describe various scenarios of the early Universe. We show that the constraints on the blue spectral tilt strongly depend on the underlying assumption and, in some cases, a highly blue-tilted spectrum can still be allowed.

  4. Numerical relativity simulations of thick accretion disks around tilted Kerr black holes

    E-Print Network [OSTI]

    Vassilios Mewes; José A. Font; Filippo Galeazzi; Pedro J. Montero; Nikolaos Stergioulas

    2015-06-12

    In this work we present 3D numerical relativity simulations of thick accretion disks around {\\it tilted} Kerr black holes. We investigate the evolution of three different initial disk models with a range of initial black hole spin magnitudes and tilt angles. For all the disk-to-black hole mass ratios considered ($0.044-0.16$) we observe significant black hole precession and nutation during the evolution. This indicates that for such mass ratios, neglecting the self-gravity of the disks by evolving them in a fixed background black hole spacetime is not justified. We find that the two more massive models are unstable against the Papaloizou-Pringle (PP) instability and that those PP-unstable models remain unstable for all initial spins and tilt angles considered, showing that the development of the instability is a very robust feature of such PP-unstable disks. The tilt between the black hole spin and the disk is strongly modulated during the growth of the PP instability, causing a partial global realignment of black hole spin and disk angular momentum in the most massive model with constant specific angular momentum $l$. For the model with non-constant $l$-profile we observe a long-lived $m=1$ non-axisymmetric structure which shows strong oscillations of the tilt angle in the inner regions of the disk. We attribute this effect to the development of Kozai-Lidov oscillations. Our simulations also confirm earlier findings that the development of the PP instability causes the long-term emission of large amplitude gravitational waves, predominantly for the $l=m=2$ multipole mode. The imprint of the BH precession on the gravitational waves from tilted BH-torus systems remains an interesting open issue that would require significantly longer simulations than those presented in this work.

  5. Design and fabrication of a 2.5T superconducting dipole prototype based on tilted solenoids

    E-Print Network [OSTI]

    Chen, Yuquan; Wu, Wei; Wu, Beimin; Yang, Tongjun; Liang, Yu

    2015-01-01

    This paper describes a new design of superconducting dipole magnet prototype by the use of tilted solenoids. The magnet prototype, which consists of four layers of superimposed tilted solenoids with operating current of 3708 A, will produce a 2.5 T magnetic field in an aperture of 50 mm diameter. The detailed magnetic field design by using two kinds of software is presented. And their results show a good agree in the magnetic fields. So far we have accomplished the prototype construction and expect a cryogenic test. The process of the magnet fabrication is also reported in detail.

  6. High-latitude dayside energetic precipitation and IMF BZ rotations N. stgaard,1

    E-Print Network [OSTI]

    California at Berkeley, University of

    . Owing to the high latitudes it is unlikely that these electrons were energized on the nightside by the solar wind. The precipitation appears at $77­79° magnetic latitude and coincides with a northward Ionosphere: Auroral ionosphere (2704); 2784 Magnetospheric Physics: Solar wind/magnetosphere interactions

  7. The influence of Southern Hemisphere seaice extent on the latitude of the midlatitude jet stream

    E-Print Network [OSTI]

    Kidston, Joseph

    The influence of Southern Hemisphere seaice extent on the latitude of the midlatitude jet stream J midlatitude jet stream, but that the amplitude of the atmospheric response depends critically on the location), The influence of Southern Hemisphere seaice extent on the latitude of the midlatitude jet stream, Geophys. Res

  8. 2005 Nature Publishing Group Simulation of equatorial and high-latitude jets on

    E-Print Network [OSTI]

    © 2005 Nature Publishing Group Simulation of equatorial and high-latitude jets on Jupiter in a deep system of powerful winds. Broad eastward equatorial jets are flanked by smaller-scale, higher-latitude jets flowing in alternating directions1,2 . Jupiter's large thermal emission suggests that the winds

  9. The Structure of the Homunculus: I. Shape and Latitude Dependence from H2 and [Fe II] Velocity Maps of Eta Carinae

    E-Print Network [OSTI]

    Nathan Smith

    2006-02-21

    High resolution long-slit spectra obtained with the Phoenix spectrograph on Gemini South provide our most accurate probe of the three dimensional structure of the Homunculus around eta Car. The new near-infrared spectra dramatically confirm the double-shell structure inferred previously from thermal dust emission, resolving the nebula into a very thin outer shell seen in H2 21218, and a warmer, thicker inner layer seen in [Fe II] 16435. The thin H2 skin hints that the most important mass loss during the 19th century eruption had a very short duration of less than 5 yr. H2 emission traces the majority of the mass in the nebula, and has an average density of order 10^6.5 cm-3. This emission, in turn, yields our first definitive picture of the exact shape of the nebula, plus a distance of 2350pm50 pc and an inclination angle of 41deg (the polar axis is tilted 49deg from the plane of the sky). The distribution of the H2 emission provides the first measure of the latitude dependence of the speed, mass loss, and kinetic energy associated with eta Car's 19th century explosion. Almost 75 percent of the total mass and more than 90 percent of the kinetic energy in the ejecta were released at high latitudes. This rules out a model for the bipolar shape wherein an otherwise spherical explosion was pinched at the waist by a circumstellar torus. Also, the ejecta could not have been deflected toward polar trajectories by a companion star, since the kinetic energy of the polar ejecta is greater than the binding energy of the putative binary system. Instead, most of the mass appears to have been directed poleward by the explosion itself. [abridged

  10. PS-wave moveout inversion for tilted TI media: A physical-modeling study Pawan Dewangan1

    E-Print Network [OSTI]

    PS-wave moveout inversion for tilted TI media: A physical-modeling study Pawan Dewangan1 , Ilya Tsvankin2 , Mike Batzle3 , Kasper van Wijk4 , and Matthew Haney5 ABSTRACT Mode-converted PS-waves can- and PS- waves can be inverted for the parameters of a horizontal TI layer with a tilted symmetry axis

  11. Irradiation Creep in Graphite

    SciTech Connect (OSTI)

    Ubic, Rick; Butt, Darryl; Windes, William

    2014-03-13

    An understanding of the underlying mechanisms of irradiation creep in graphite material is required to correctly interpret experimental data, explain micromechanical modeling results, and predict whole-core behavior. This project will focus on experimental microscopic data to demonstrate the mechanism of irradiation creep. High-resolution transmission electron microscopy should be able to image both the dislocations in graphite and the irradiation-induced interstitial clusters that pin those dislocations. The team will first prepare and characterize nanoscale samples of virgin nuclear graphite in a transmission electron microscope. Additional samples will be irradiated to varying degrees at the Advanced Test Reactor (ATR) facility and similarly characterized. Researchers will record microstructures and crystal defects and suggest a mechanism for irradiation creep based on the results. In addition, the purchase of a tensile holder for a transmission electron microscope will allow, for the first time, in situ observation of creep behavior on the microstructure and crystallographic defects.

  12. Proto-CIRCUS Tilted-Coil Tokamak-Torsatron Hybrid: Design and Construction

    E-Print Network [OSTI]

    Clark, A W; Hammond, K C; Kornbluth, Y; Spong, D A; Sweeney, R; Volpe, F A

    2014-01-01

    We present the field-line modeling, design and construction of a prototype circular-coil tokamak-torsatron hybrid called Proto-CIRCUS. The device has a major radius R = 16 cm and minor radius a < 5 cm. The six "toroidal field" coils are planar as in a tokamak, but they are tilted. This, combined with induced or driven plasma current, is expected to generate rotational transform, as seen in field-line tracing and equilibrium calculations. The device is expected to operate at lower plasma current than a tokamak of comparable size and magnetic field, which might have interesting implications for disruptions and steady-state operation. Additionally, the toroidal magnetic ripple is less pronounced than in an equivalent tokamak in which the coils are not tilted. The tilted coils are interlocked, resulting in a relatively low aspect ratio, and can be moved, both radially and in tilt angle, between discharges. This capability will be exploited for detailed comparisons between calculations and field-line mapping me...

  13. An Experimental Study of Oil Secondary Migration in a Three Dimensional Tilted Porous Medium

    E-Print Network [OSTI]

    Toussaint, Renaud

    . With the buoyancy as a primary driven force, a vertical cylindrical shape of oil migration pathway was observedAn Experimental Study of Oil Secondary Migration in a Three Dimensional Tilted Porous Medium secondary migration under an impermeable inclined cap. Light colored oil was released continuously at a slow

  14. The Loreto basin formed by rapid west-ward tilting and asymmetric subsidence with-

    E-Print Network [OSTI]

    Dorsey, Becky

    ABSTRACT The Loreto basin formed by rapid west- ward tilting and asymmetric subsidence with subsidence histories and stratigraphic evolution. Sedimentary rocks of the Loreto basin are divided into four stratigraphic se- quences that record discrete phases of fault- controlled subsidence and basin filling. Se

  15. Measurement of chain tilt angle in fully hydrated bilayers of gel phase lecithins

    E-Print Network [OSTI]

    Nagle, John F.

    Measurement of chain tilt angle in fully hydrated bilayers of gel phase lecithins S. Tristram angle Otilt of the hydrocarbon chains has been determined for the fully hydrated gel phase of a series hydrocarbon chains, requiring each bilayer to scatter coherently rather than each monolayer. For DPPC, Otilt

  16. Turbulent velocity profiles in a tilted heat pipe J. Salort, X. Riedinger,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Turbulent velocity profiles in a tilted heat pipe J. Salort, X. Riedinger, E. Rusaouen, J the ther- mal behavior of a square heat pipe, depending on its inclination angle and the applied heat flux (stresses). Heat pipes, or gravital flows in vertical or inclined Also at College of Engineering

  17. Pulse-front tilt created in misaligned dispersionless optical systems and correct interferometric

    E-Print Network [OSTI]

    Dreischuh, Alexander

    Pulse-front tilt created in misaligned dispersionless optical systems and correct interferometric-temporal distortions of ultrashort laser pulses. Special attention is given to the possible creation of a pulse of the ultrashort pulses in the presence of an arbitrary PFT . Key words: spatio-temporal distortion, dispersionless

  18. Uranium vacancy mobility at the ?5 symmetric tilt and ?5 twist grain boundaries in UO?

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

    Uberuaga, Blas Pedro; Andersson, David A.

    2015-10-01

    Ionic transport at grain boundaries in oxides dictates a number of important phenomena, from ionic conductivity to sintering to creep. For nuclear fuels, it also influences fission gas bubble nucleation and growth. Here, using a combination of atomistic calculations and object kinetic Monte Carlo (okMC) simulations, we examine the kinetic pathways associated with uranium vacancies at two model grain boundaries in UO2. The barriers for vacancy motion were calculated using the nudged elastic band method at all uranium sites at each grain boundary and were used as the basis of the okMC simulations. For both boundaries considered – a simplemore »tilt and a simple twist boundary – the mobility of uranium vacancies is significantly higher than in the bulk. For the tilt boundary, there is clearly preferred migration along the tilt axis as opposed to in the perpendicular direction while, for the twist boundary, migration is essentially isotropic within the boundary plane. These results show that cation defect mobility in fluorite-structured materials is enhanced at certain types of grain boundaries and is dependent on the boundary structure with the tilt boundary exhibiting higher rates of migration than the twist boundary.« less

  19. Tilting mirror strips in a linear Fresnel reector Gang Xiao (University of Nice, France)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Tilting mirror strips in a linear Fresnel reector Gang Xiao (University of Nice, France) February 29, 2012 Abstract When a linear Fresnel reector solar concentrator is installed in a site with high of the linear Fresnel reector. Technical restrictions and diculties of this method are also discussed

  20. Seismic evidence for a tilted mantle plume and north^south mantle ow beneath Iceland

    E-Print Network [OSTI]

    Shen, Yang

    Seismic evidence for a tilted mantle plume and north^south mantle £ow beneath Iceland Yang Shen a.W., Washington, DC 20015, USA c Science Institute, University of Iceland, Reykjavik, Iceland d Department, Grensasvegi 9, Reykjavik, Iceland f Meteorological O/ce of Iceland, Bustadavegi 9, Reykjavik, Iceland g US

  1. First results of a polychromatic artificial sodium star for the correction of tilt

    SciTech Connect (OSTI)

    Friedman, H.; Foy, R..; Tallon, M.; Migus, A.

    1996-03-06

    This paper presents the first results of a joint experiment carried out at Lawrence Livermore National Laboratory during January, 1996. Laser and optical systems were tested to provide a polychromatic artificial sodium star for the correction of tilt. This paper presents the results of that experiment.

  2. Evidence of a tilted columnar structure for mesomorphic phases of benzene-hexa-n-alkanoates

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1285 Evidence of a tilted columnar structure for mesomorphic phases of benzene-hexa-n-alkanoates F. 2014 Optical observations on the mesomorphs of benzene-hexa-n-alkanoates, and their admixtures with benzene, show that the planes of these discotic molecules are not perpendicular to the columns in which

  3. Selection of a numerical unsaturated flow code for tilted capillary barrier performance evaluation

    SciTech Connect (OSTI)

    Webb, S.W. [Sandia National Labs., Albuquerque, NM (United States). Geohydrology Dept.

    1996-09-01

    Capillary barriers consisting of tilted fine-over-coarse layers have been suggested as landfill covers as a means to divert water infiltration away from sensitive underground regions under unsaturated flow conditions, especially for arid and semi-arid regions. Typically, the HELP code is used to evaluate landfill cover performance and design. Unfortunately, due to its simplified treatment of unsaturated flow and its essentially one-dimensional nature, HELP is not adequate to treat the complex multidimensional unsaturated flow processes occurring in a tilted capillary barrier. In order to develop the necessary mechanistic code for the performance evaluation of tilted capillary barriers, an efficient and comprehensive unsaturated flow code needs to be selected for further use and modification. The present study evaluates a number of candidate mechanistic unsaturated flow codes for application to tilted capillary barriers. Factors considered included unsaturated flow modeling, inclusion of evapotranspiration, nodalization flexibility, ease of modification, and numerical efficiency. A number of unsaturated flow codes are available for use with different features and assumptions. The codes chosen for this evaluation are TOUGH2, FEHM, and SWMS{_}2D. All three codes chosen for this evaluation successfully simulated the capillary barrier problem chosen for the code comparison, although FEHM used a reduced grid. The numerical results are a strong function of the numerical weighting scheme. For the same weighting scheme, similar results were obtained from the various codes. Based on the CPU time of the various codes and the code capabilities, the TOUGH2 code has been selected as the appropriate code for tilted capillary barrier performance evaluation, possibly in conjunction with the infiltration, runoff, and evapotranspiration models of HELP. 44 refs.

  4. HIGH ECLIPTIC LATITUDE SURVEY FOR SMALL MAIN-BELT ASTEROIDS

    SciTech Connect (OSTI)

    Terai, Tsuyoshi [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Takahashi, Jun; Itoh, Yoichi, E-mail: tsuyoshi.terai@nao.ac.jp [Center for Astronomy, University of Hyogo, 407-2 Nishigaichi, Sayo-cho, Sayo-gun, Hyogo 679-5313 (Japan)

    2013-11-01

    Main-belt asteroids have been continuously colliding with one another since they were formed. Their size distribution is primarily determined by the size dependence of asteroid strength against catastrophic impacts. The strength scaling law as a function of body size could depend on collision velocity, but the relationship remains unknown, especially under hypervelocity collisions comparable to 10 km s{sup –1}. We present a wide-field imaging survey at an ecliptic latitude of about 25° for investigating the size distribution of small main-belt asteroids that have highly inclined orbits. The analysis technique allowing for efficient asteroid detections and high-accuracy photometric measurements provides sufficient sample data to estimate the size distribution of sub-kilometer asteroids with inclinations larger than 14°. The best-fit power-law slopes of the cumulative size distribution are 1.25 ± 0.03 in the diameter range of 0.6-1.0 km and 1.84 ± 0.27 in 1.0-3.0 km. We provide a simple size distribution model that takes into consideration the oscillations of the power-law slope due to the transition from the gravity-scaled regime to the strength-scaled regime. We find that the high-inclination population has a shallow slope of the primary components of the size distribution compared to the low-inclination populations. The asteroid population exposed to hypervelocity impacts undergoes collisional processes where large bodies have a higher disruptive strength and longer lifespan relative to tiny bodies than the ecliptic asteroids.

  5. Decomposing Atmospheric Versus Oceanic Contributions to the High-To-Low Latitude Teleconnection during a Freshwater Triggered Abrupt Climate Change 

    E-Print Network [OSTI]

    Tang, Guanglin

    2015-07-24

    In this dissertation we study the high-to-low latitude teleconnection during Younger Dryas-like abrupt climate events using models. The teleconnection considered here is between climate change induced by a freshwater input in high-latitude North...

  6. Design and construction of a novel quad tilt-wing UAV E. Cetinsoy, S. Dikyar, C. Hancer, K.T. Oner, E. Sirimoglu, M. Unel

    E-Print Network [OSTI]

    Ã?nel, Mustafa

    Design and construction of a novel quad tilt-wing UAV E. Cetinsoy, S. Dikyar, C. Hancer, K.T. Oner 12 March 2012 Available online xxxx Keywords: UAV Quad tilt-wing Aerodynamic design Carbon composite VehIcle). SUAVI is an electric powered quad tilt-wing UAV that is capable of vertical takeoff

  7. Influence of eddydriven jet latitude on North Atlantic jet persistence and blocking frequency in CMIP3 integrations

    E-Print Network [OSTI]

    Hartmann, Dennis

    Influence of eddydriven jet latitude on North Atlantic jet persistence and blocking frequency Atlantic jet latitude is analyzed in 45 CMIP3 integrations. It is demonstrated that models that place the jet equatorward of its observed position have more positively skewed jet latitude distributions, while

  8. alkenones advected by deep waters originating from high northern latitudes is thus very unlikely.

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    alkenones advected by deep waters originating from high northern latitudes is thus very unlikely, 359 (1998). 39. C. Sonzogni et al., Deep-Sea Res. II 44, 1445 (1997). 40. F. G. Prahl, L. A

  9. Diffuse Galactic Light in the Field of the Translucent High Galactic Latitude Cloud MBM32

    E-Print Network [OSTI]

    Ienaka, N; Matsuoka, Y; Sameshima, H; Oyabu, S; Tsujimoto, T; Peterson, B A

    2013-01-01

    We have conducted B, g, V, and R-band imaging in a 45x40 arcmin^2 field containing part of the high Galactic latitude translucent cloud MBM32, and correlated the intensity of diffuse optical light S_\

  10. Desertification of high latitude ecosystems: conceptual models, time-series analyses and experiments 

    E-Print Network [OSTI]

    Thorsson, Johann

    2009-05-15

    -1 DESERTIFICATION OF HIGH LATITUDE ECOSYSTEMS: CONCEPTUAL MODELS, TIME-SERIES ANALYSES AND EXPERIMENTS A Dissertation by JOHANN THORSSON Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of DOCTOR OF PHILOSOPHY December 2008 Major Subject: Rangeland Ecology and Management DESERTIFICATION OF HIGH LATITUDE ECOSYSTEMS: CONCEPTUAL MODELS, TIME-SERIES ANALYSES AND EXPERIMENTS A Dissertation by JOHANN...

  11. MERIDIONAL TILT OF THE STELLAR VELOCITY ELLIPSOID DURING BAR BUCKLING INSTABILITY

    SciTech Connect (OSTI)

    Saha, Kanak [Max-Planck-Institut fuer Extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany)] [Max-Planck-Institut fuer Extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Pfenniger, Daniel [Geneva Observatory, University of Geneva, CH-1290 Sauverny (Switzerland)] [Geneva Observatory, University of Geneva, CH-1290 Sauverny (Switzerland); Taam, Ronald E., E-mail: saha@mpe.mpg.de [Institute of Astronomy and Astrophysics, Academia Sinica-TIARA, Taiwan (China)

    2013-02-20

    The structure and evolution of the stellar velocity ellipsoid play an important role in shaping galaxies undergoing bar-driven secular evolution and the eventual formation of a boxy/peanut bulge such as is present in the Milky Way. Using collisionless N-body simulations, we show that during the formation of such a boxy/peanut bulge, the meridional shear stress of stars, which can be measured by the meridional tilt of the velocity ellipsoid, reaches a characteristic peak in its time evolution. It is shown that the onset of a bar buckling instability is closely connected to the maximum meridional tilt of the stellar velocity ellipsoid. Our findings bring a new insight to this complex gravitational instability of the bar which complements the buckling instability studies based on orbital models. We briefly discuss the observed diagnostics of the stellar velocity ellipsoid during such a phenomenon.

  12. A counter-rotating tilted gas disc in the peanut galaxy NGC~128

    E-Print Network [OSTI]

    Eric Emsellem; Robin Arsenault

    1997-01-15

    We have obtained $V$, $R_c$, $I_c$ HRCAM images and TIGER spectrography of the central region of the peanut galaxy NGC~128. The colour images reveal the presence of a red disc tilted by about 26 degres with respect to the major-axis of the galaxy. This tilted disc is made of dust and gas, as revealed by the 2D TIGER map of the ionized gas distribution. The TIGER stellar and gas velocity fields show that the angular momentum vectors of the stellar and gaseous components are reversed. We therefore suggest that the gas orbits belong to the so-called anomalous family, which is evidence for a tumbling triaxial potential (a bar) associated with the peanut morphology. The bar formation has very probably been triggered through the interaction with its nearby companion NGC~127, from which the dissipative component is being accreted along retrograde orbits.

  13. Dipolar Capillary Interactions between Tilted Ellipsoidal Particles Adsorbed at Fluid-Fluid Interfaces

    E-Print Network [OSTI]

    Gary B. Davies; Lorenzo Botto

    2015-07-22

    Capillary interactions have emerged as a tool for the directed assembly of particles adsorbed at fluid-fluid interfaces, and play a role in controlling the mechanical properties of emulsions and foams. In this paper, following Davies et al. [Advanced Materials, 26, 6715 (2014)] investigation into the assembly of ellipsoidal particles at interfaces interacting via dipolar capillary interactions, we numerically investigate the interaction between tilted ellipsoidal particles adsorbed at a fluid-fluid interface as their aspect ratio, tilt angle, bond angle, and separation vary. High-resolution Surface Evolver simulations of ellipsoidal particle pairs in contact reveal an energy barrier between a metastable tip-tip configuration and a stable side-side configuration. The side-side configuration is the global energy minimum for all parameters we investigated. Lattice Boltzmann simulations of clusters of up to 12 ellipsoidal particles show novel highly symmetric flower-like and ring-like arrangements.

  14. Sunspot areas and tilt angles for solar cycles 7-10

    E-Print Network [OSTI]

    Pavai, V Senthamizh; Dasi-Espuig, M; Krivova, N; Solanki, S

    2015-01-01

    Extending the knowledge about the properties of solar cycles into the past is essential for understanding the solar dynamo. This paper aims at estimating areas of sunspots observed by Schwabe in 1825-1867 and at calculating the tilt angles of sunspot groups. The sunspot sizes in Schwabe's drawings are not to scale and need to be converted into physical sunspot areas. We employed a statistical approach assuming that the area distribution of sunspots was the same in the 19th century as it was in the 20th century. Umbral areas for about 130,000 sunspots observed by Schwabe were obtained, as well as the tilt angles of sunspot groups assuming them to be bipolar. There is, of course, no polarity information in the observations. The annually averaged sunspot areas correlate reasonably with sunspot number. We derived an average tilt angle by attempting to exclude unipolar groups with a minimum separation of the two alleged polarities and an outlier rejection method which follows the evolution of each group and detect...

  15. Red and blue tilted tensor spectrum from Gibbons-Hawking temperature

    E-Print Network [OSTI]

    Subhendra Mohanty; Akhilesh Nautiyal

    2015-01-09

    The scale invariant scalar and tensor perturbations, which are predicted from inflation, are eigenmodes in the conformal coordinates. The 'out' observer in the de Sitter space observes a thermal spectrum with a Gibbons-Hawking temperature $H/2\\pi$ of these 'Bunch-Davies' particles. The tensor power spectrum observed in experiments can have an imprint of the Gibbons-Hawking thermal distribution due to the mode mixing between 'in' state conformal coordinates and the coordinate frame of the observer. We find that the the Bunch-Davies modes appear as thermal modes to the asymptotic Minkowski observer in the future and the power spectrum of the gravitational waves is blue-tilted with a spectral index $n_T \\sim 1$ even in the standard slow-roll inflation. On the other hand if the coordinate frame of the observer is taken to be static coordinates, the tensor spectrum is red-tilted with $n_T\\sim -1$. A likelihood analysis shows and find the best fit values of the slow-roll parameters for both cases. We find that the blue-tilted tensor gives a better fit and reconciles the PLANCK upper bound on the tensor-to-scalar ratio, $r <0.11$ with BICEP2 measurement of $r=0.2$. This supports the idea of particle production due to the mode mixing between the initial Bunch-Davies vacuum modes and the asymptotic Minkowski vacuum of the post-inflation universe.

  16. Cosmological signatures of tilted isocurvature perturbations: reionization and 21cm fluctuations

    SciTech Connect (OSTI)

    Sekiguchi, Toyokazu; Sugiyama, Naoshi; Tashiro, Hiroyuki; Silk, Joseph E-mail: hiroyuki.tashiro@asu.edu E-mail: naoshi@nagoya-u.jp

    2014-03-01

    We investigate cosmological signatures of uncorrelated isocurvature perturbations whose power spectrum is blue-tilted with spectral index 2?tilted isocurvature primordial power spectrum. We also study the consequences for 21cm line fluctuations due to neutral hydrogens in minihalos. Combination of measurements of the reionization optical depth and 21cm line fluctuations will provide complementary probes of a highly blue-tilted isocurvature power spectrum.

  17. Effects of head-up tilt on mean arterial pressure, heart rate, and regional cardiac output distribution in aging rats 

    E-Print Network [OSTI]

    Ramsey, Michael Wiechmann

    2006-04-12

    Many senescent individuals demonstrate an inability to regulate mean arterial pressure (MAP) in response to standing or head-up tilt; however, whether this aging effect is the result of depressed cardiac function or an inability to reduce peripheral...

  18. Effects of the scatter in sunspot group tilt angles on the large-scale magnetic field at the solar surface

    SciTech Connect (OSTI)

    Jiang, J.; Cameron, R. H.; Schüssler, M.

    2014-08-10

    The tilt angles of sunspot groups represent the poloidal field source in Babcock-Leighton-type models of the solar dynamo and are crucial for the build-up and reversals of the polar fields in surface flux transport (SFT) simulations. The evolution of the polar field is a consequence of Hale's polarity rules, together with the tilt angle distribution which has a systematic component (Joy's law) and a random component (tilt-angle scatter). We determine the scatter using the observed tilt angle data and study the effects of this scatter on the evolution of the solar surface field using SFT simulations with flux input based upon the recorded sunspot groups. The tilt angle scatter is described in our simulations by a random component according to the observed distributions for different ranges of sunspot group size (total umbral area). By performing simulations with a number of different realizations of the scatter we study the effect of the tilt angle scatter on the global magnetic field, especially on the evolution of the axial dipole moment. The average axial dipole moment at the end of cycle 17 (a medium-amplitude cycle) from our simulations was 2.73 G. The tilt angle scatter leads to an uncertainty of 0.78 G (standard deviation). We also considered cycle 14 (a weak cycle) and cycle 19 (a strong cycle) and show that the standard deviation of the axial dipole moment is similar for all three cycles. The uncertainty mainly results from the big sunspot groups which emerge near the equator. In the framework of Babcock-Leighton dynamo models, the tilt angle scatter therefore constitutes a significant random factor in the cycle-to-cycle amplitude variability, which strongly limits the predictability of solar activity.

  19. Estimating solar irradiance using a geostationary satellite

    E-Print Network [OSTI]

    Urquhart, Bryan Glenn

    2011-01-01

    Heliosat procedure for irradiance Estimates from Satellitethe pro duction of solar irradiance and daylight illuminancesatellite based solar irradiance modelling - The SOLIS clear

  20. IRRADIATION OF 3- SUBSTITUTED-2-PHENYLOXAZIRIDINES

    E-Print Network [OSTI]

    Splitter, Janet S.; Calvin, Melvin.

    2008-01-01

    1 . These oxaziridines from irradiation of the corresponding1). A complication in the irradiation of the ozaziridines isof imine formed in the irradiation of the oxaziridines. (

  1. Irradiation Stability of Carbon Nanotubes 

    E-Print Network [OSTI]

    Aitkaliyeva, Assel

    2010-01-14

    was revealed by Raman spectroscopy study of irradiated carbon buckypapers. The deviations from linear relationship were observed for the samples irradiated to very high fluence values. Annealing of irradiated samples was able to reduce the value of ID/IG ratio...

  2. Small-scale anisotropy and intermittency in high and low-latitude solar wind

    E-Print Network [OSTI]

    A. Bigazzi; L. Biferale; S. M. A. Gama; M. Velli

    2004-12-14

    We analyze low and high--latitude fast solar wind data from the Ulysses spacecraft from 1992 to 1994 using a a systematic method to analyse the anisotropic content of the magnetic field fluctuations. We investigate all available frequencies, 1-10^{-6} Hz, for both high and low--latitudes datasets and are able to quantify the relative importance of the anisotropic versus the isotropic fluctuations. We analyse, up to sixth order, longitudinal, transverse and mixed magnetic field correlations. Our results show that strongly intermittent and anisotropic events are present in the solar wind plasma at high frequencies/small scales, indicating the absence of a complete recovery of isotropy. Anisotropic scaling properties are compatible for high and low--latitude data, suggesting a universal behaviour in spite of the different rate of evolution of the fast solar wind streams in the two environments.

  3. Entanglement, avoided crossings, and quantum chaos in an Ising model with a tilted magnetic field

    SciTech Connect (OSTI)

    Karthik, J.; Sharma, Auditya; Lakshminarayan, Arul [Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India)

    2007-02-15

    We study a one-dimensional Ising model with a magnetic field and show that tilting the field induces a transition to quantum chaos. We explore the stationary states of this Hamiltonian to show the intimate connection between entanglement and avoided crossings. In general, entanglement gets exchanged between the states undergoing an avoided crossing with an overall enhancement of multipartite entanglement at the closest point of approach, simultaneously accompanied by diminishing two-body entanglement as measured by concurrence. We find that both for stationary as well as nonstationary states, nonintegrability leads to a destruction of two-body correlations and distributes entanglement more globally.

  4. Dual-frequency terahertz emission from splitting filaments induced by lens tilting in air

    SciTech Connect (OSTI)

    Zhang, Zhelin; Chen, Yanping Yang, Liu; Yuan, Xiaohui; Liu, Feng; Chen, Min; Xu, Jianqiu; Zhang, Jie; Sheng, Zhengming

    2014-09-08

    Dual-frequency terahertz radiation from air-plasma filaments produced with two-color lasers in air has been demonstrated experimentally. When a focusing lens is tilted for a few degrees, it is shown that the laser filament evolves from a single one to two sub-filaments. Two independent terahertz sources emitted from the sub-filaments with different frequencies and polarizations are identified, where the frequency of terahertz waves from the trailing sub-filament is higher than that from the leading sub-filament.

  5. Accurate measurement of relative tilt and azimuth angles in electron tomography: A comparison of fiducial marker method with electron diffraction

    SciTech Connect (OSTI)

    Hayashida, Misa [National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1, Higashi, Tsukuba, Ibaraki 305-8565 (Japan); Malac, Marek; Egerton, Ray F. [National Institute for Nanotechnology, 11421 Saskatchewan Drive, Edmonton T6G 2M9 (Canada); Department of Physics, University of Alberta, Edmonton T6H 2E1 (Canada); Bergen, Michael; Li, Peng [National Institute for Nanotechnology, 11421 Saskatchewan Drive, Edmonton T6G 2M9 (Canada)

    2014-08-15

    Electron tomography is a method whereby a three-dimensional reconstruction of a nanoscale object is obtained from a series of projected images measured in a transmission electron microscope. We developed an electron-diffraction method to measure the tilt and azimuth angles, with Kikuchi lines used to align a series of diffraction patterns obtained with each image of the tilt series. Since it is based on electron diffraction, the method is not affected by sample drift and is not sensitive to sample thickness, whereas tilt angle measurement and alignment using fiducial-marker methods are affected by both sample drift and thickness. The accuracy of the diffraction method benefits reconstructions with a large number of voxels, where both high spatial resolution and a large field of view are desired. The diffraction method allows both the tilt and azimuth angle to be measured, while fiducial marker methods typically treat the tilt and azimuth angle as an unknown parameter. The diffraction method can be also used to estimate the accuracy of the fiducial marker method, and the sample-stage accuracy. A nano-dot fiducial marker measurement differs from a diffraction measurement by no more than ±1°.

  6. Early structure formation from primordial density fluctuations with a blue-tilted power spectrum

    E-Print Network [OSTI]

    Hirano, Shingo; Yoshida, Naoki; Spergel, David; Yorke, Harold W

    2015-01-01

    While observations of large-scale structure and the cosmic microwave background (CMB) provide strong constraints on the amplitude of the primordial power spectrum (PPS) on scales larger than 10 Mpc, the amplitude of the power spectrum on sub-galactic length scales is much more poorly constrained. We study early structure formation in a cosmological model with a blue-tilted PPS. We assume that the standard scale-invariant PPS is modified at small length scales as $P(k) \\sim k^{m_{\\rm s}}$ with $m_{\\rm s} > 1$. We run a series of cosmological hydrodynamic simulations to examine the dependence of the formation epoch and the characteristic mass of primordial stars on the tilt of the PPS. In models with $m_{\\rm s} > 1$, star-forming gas clouds are formed at $z > 100$, when formation of hydrogen molecules is inefficient because the intense CMB radiation destroys chemical intermediates. Without efficient coolant, the gas clouds gravitationally contract while keeping a high temperature. The protostars formed in such ...

  7. Effect of tilting on turbulent convection: Cylindrical samples with aspect ratio $\\Gamma=0.50$

    E-Print Network [OSTI]

    Weiss, Stephan

    2015-01-01

    We report measurements of properties of turbulent thermal convection of a fluid with a Prandtl number $\\Pra=4.38$ in a cylindrical cell with an aspect ratio $\\Gamma=0.50$. The rotational symmetry was broken by a small tilt of the sample axis relative to gravity. Measurements of the heat transport (as expressed by the Nusselt number \\Nu), as well as of large-scale-circulation (LSC) properties by means of temperature measurements along the sidewall, are presented. In contradistinction to similar experiments using containers of aspect ratio $\\Gamma=1.00$ \\cite[]{ABN06} and $\\Gamma=0.50$ \\cite[]{CRCC04,SXX05,RGKS10}, we see a very small increase of the heat transport for tilt angles up to about 0.1 rad. Based on measurements of properties of the LSC we explain this increase by a stabilization of the single-roll state (SRS) of the LSC and a de-stabilization of the double-roll state (DRS) (it is known from previous work that the SRS has a slightly larger heat transport than the DRS). Further, we present quantitativ...

  8. THE TRANSIT INGRESS AND THE TILTED ORBIT OF THE EXTRAORDINARILY ECCENTRIC EXOPLANET HD 80606b

    SciTech Connect (OSTI)

    Winn, Joshua N.; Howard, Andrew W.; Marcy, Geoffrey W.; Johnson, John Asher; Gazak, J. Zachary; Starkey, Donn; Ford, Eric B.; Colon, Knicole D.; Reyes, Francisco; Nortmann, Lisa; Dreizler, Stefan; Odewahn, Stephen; Welsh, William F.; Kadakia, Shimonee; Vanderbei, Robert J.; Adams, Elisabeth R.; Lockhart, Matthew; Crossfield, Ian J.; Valenti, Jeff A.; Dantowitz, Ronald

    2009-10-01

    We present the results of a transcontinental campaign to observe the 2009 June 5 transit of the exoplanet HD 80606b. We report the first detection of the transit ingress, revealing the transit duration to be 11.64 +- 0.25 hr and allowing more robust determinations of the system parameters. Keck spectra obtained at midtransit exhibit an anomalous blueshift, giving definitive evidence that the stellar spin axis and planetary orbital axis are misaligned. The Keck data show that the projected spin-orbit angle lambda is between 32 deg. and 87 deg. with 68.3% confidence and between 14 deg. and 142 deg. with 99.73% confidence. Thus, the orbit of this planet is not only highly eccentric (e = 0.93) but is also tilted away from the equatorial plane of its parent star. A large tilt had been predicted, based on the idea that the planet's eccentric orbit was caused by the Kozai mechanism. Independently of the theory, it is worth noting that all three exoplanetary systems with known spin-orbit misalignments have massive planets on eccentric orbits, suggesting that those systems migrate through a different channel than lower mass planets on circular orbits.

  9. Estimating the Response of Extreme Precipitation over Mid-latitude1 Mountains to Global Warming2

    E-Print Network [OSTI]

    Estimating the Response of Extreme Precipitation over Mid-latitude1 Mountains to Global Warming2@atmos.washington.edu8 Generated using v4.3.1 (5-19-2014) of the AMS LATEX template1 #12;ABSTRACT Global warming induced-wave theory as arising from global-warming in- duced changes in the upper-tropospheric static stability

  10. Phylogeny of ulotrichalean algae from extreme high-altitude and high-latitude ecosystems

    E-Print Network [OSTI]

    Colorado at Boulder, University of

    Phylogeny of ulotrichalean algae from extreme high-altitude and high-latitude ecosystems S. K the terrestrial algae that are found in these systems. Here, we show that terrestrial algae in the Ulotrichales and the high Himalayas. We further show that these ulotrichalean algae are closely related (using 18S, ITS/5.8S

  11. Axial obliquity control on the greenhouse carbon budget through middle-to high-latitude reservoirs

    E-Print Network [OSTI]

    Meyers, Stephen R.

    Axial obliquity control on the greenhouse carbon budget through middle- to high-latitude reservoirs for past greenhouse climates. Carbon-isotope data indicate systematic, million-year-scale transfers-stable character, they might have provided an important control on the dynamics and stability of the greenhouse

  12. Discovery of Eight Recycled Pulsars - The Swinburne Intermediate Latitude Pulsar Survey

    E-Print Network [OSTI]

    R. T. Edwards

    1999-11-19

    We have conducted a pulsar survey of intermediate Galactic latitudes (15deg 0.57 Mo and > 1.2 Mo), while anotherhas a low mass (~0.2 Mo) companion in a 23.3-d orbit, residing the well-known orbital period ``gap''.

  13. Statistical maps of small-scale electric field variability in the high-latitude ionosphere

    E-Print Network [OSTI]

    Shepherd, Simon

    and the solar wind. The ionospheric electric fields, which are associated with plasma drifts, inject energy characterizing the dependence of high-latitude electric fields on solar wind or geomagnetic conditions, many factors that impact the observed small-scale electric field variability. In general, Southern Hemisphere

  14. Ulysses Radio and Plasma Wave Observations at High Southern Heliographic Latitudes

    E-Print Network [OSTI]

    California at Berkeley, University of

    Ulysses Radio and Plasma Wave Observations at High Southern Heliographic Latitudes R. G. Stone, R-Frey, R. Manning, M. J. Reiner, J. L. Steinberg, G. Thejappa Ulysses spacecraft radio and plasma wave wind. Radio and plasma wave observations, such as those made by the Unified Radio and Plasma Wave

  15. Semi-empirical low-latitude ionospheric model. Environmental research papers

    SciTech Connect (OSTI)

    Anderson, D.N.; Mendillo; Herniter

    1985-10-10

    Since current empirical models specifying low-latitude electron density profiles severely underestimate the daytime plasma density scale-height and total electron content (TEC), a Semi-empirical, Low-latitude, Ionospheric Model (SLIM) was developed that is not only more realistic but is also computationally fast. Electron-density profiles (180 to 1800 km) are theoretically calculated as a function of latitude (every 2/sup 0/ between 24 N and 24 S dip latitude) and local time (every half-hour over 24 hours LT) by solving the time-dependent plasma-continuity equation. Assuming a Chapman-like profile, sets coefficients are then generated that reproduce these individual profiles. The coefficients themselves are easily stored, quickly retrieved, and form the basis for a fast, portable, semi-empirical computer code. This report describes briefly the input parameters used to theoretically calculate profiles and the procedures used to generate the coefficients. The SLIM profiles are compared with the Chiu and Bent empirical models for Equinox, solar-maximum conditions. Finally, electron densities, the coefficients, TEC and 6300 A airglow intensities are listed in tabular form for three seasons (Equinox, June solstice, and December solstice) and two solar-cycle periods (solar maximum and solar minimum).

  16. Mechanisms that control the latitude of jet streams and surface westerlies

    E-Print Network [OSTI]

    Chen, Gang

    Mechanisms that control the latitude of jet streams and surface westerlies Gang Chen A Dissertation sur- face westerlies to upper tropospheric jets, in response to several major climate forcings the mechanisms for these jet movements, using more generic forcings such as changes in surface friction

  17. Advantageous GOES IR results for ash mapping at high latitudes: Cleveland eruptions 2001

    E-Print Network [OSTI]

    Bluth, Gregg

    Advantageous GOES IR results for ash mapping at high latitudes: Cleveland eruptions 2001 Yingxin Gu] The February 2001 eruption of Cleveland Volcano, Alaska allowed for comparisons of volcanic ash detection using angle also influences the results. The MODIS and AVHRR data give consistent retrievals of the ash cloud

  18. On scaling cosmogenic nuclide production rates for altitude and latitude using cosmic-ray measurements

    E-Print Network [OSTI]

    Zreda, Marek

    On scaling cosmogenic nuclide production rates for altitude and latitude using cosmic 2001 Abstract The wide use of cosmogenic nuclides for dating terrestrial landforms has prompted for production rates of cosmogenic nuclides. Over the past 50 years, the overwhelming majority of nucleon flux

  19. Extended scaling factors for in situ cosmogenic nuclides: New measurements at low latitude

    E-Print Network [OSTI]

    Zreda, Marek

    Extended scaling factors for in situ cosmogenic nuclides: New measurements at low latitude Darin. Farley Abstract Production rates of cosmogenic nuclides at the earth's surface are controlled of how nucleon fluxes vary with elevation remains a major obstacle to utilizing cosmogenic nuclides

  20. Observations of atmospheric tides on Mars at the season and latitude of the Phoenix atmospheric entry

    E-Print Network [OSTI]

    Withers, Paul

    Observations of atmospheric tides on Mars at the season and latitude of the Phoenix atmospheric atmospheric entry of NASA's Phoenix Mars probe using Phoenix Atmospheric Structure Experiment (ASE) data atmospheric entry, Geophys. Res. Lett., 37, L24204, doi:10.1029/2010GL045382. 1. Introduction [2] Phoenix

  1. Analyzing and simulating the variability of solar irradiance and solar PV powerplants

    E-Print Network [OSTI]

    Lave, Matthew S.

    2012-01-01

    Optimum tilt of a solar collector, Solar & Wind Technology,and orientation for solar collector in Brunei Darussalam,Optimum tilt angle for solar collectors. , Energy Sources,

  2. Cutaneous fusariosis developing in a post-irradiation site

    E-Print Network [OSTI]

    2011-01-01

    developing in a post-irradiation site WeiWei Dai DO 1 ,irradiated site. Irradiation led to atrophy, contraction,radiotherapy. Following irradiation, which had eradicated

  3. Crystal structures of two-dimensional magnetic colloids in tilted external magnetic fields V. A. Froltsov, R. Blaak, C. N. Likos, and H. Lowen

    E-Print Network [OSTI]

    Likos, Christos N.

    Crystal structures of two-dimensional magnetic colloids in tilted external magnetic fields V. A; published 30 December 2003 The stability of different crystal lattices of two-dimensional superparamagnetic suspensions that are confined to a planar liquid-gas interface and exposed to a tilted external magnetic field

  4. Irradiance or luminosity changes?

    E-Print Network [OSTI]

    Sabatino Sofia; Linghuai H. Li

    2000-10-20

    Whereas a variation of the solar luminosity, L, will inevitably cause a similar change of the total solar irradiance, S, the opposite is not true. In fact, the bulk of the days to months variations of S can be explained entirely in terms of the passage of active regions across the solar disk. In this case, L remains essentially unchanged. For the total irradiance variation observed over the solar cycle, the issue is more uncertain. One view explains this modulation primarily as a combined action of active regions and magnetic network. These components would be superposed to an otherwise unchanging photosphere. the other view suggests that the activity cycle modulation of S is primarily produced by a variation of L (both in terms of R and T_{eff}) caused by structural reajustments of the interior of the Sun induced by a changing magnetic field. We will present evidence in support of this second interpretation, and a model for it. We will also present the S variations over the last 5 centuries implied by our model.

  5. Three-dimensional microelectromechanical tilting platform operated by gear-driven racks

    DOE Patents [OSTI]

    Klody, Kelly A.; Habbit, Jr., Robert D.

    2005-11-01

    A microelectromechanical (MEM) tiltable-platform apparatus is disclosed which utilizes a light-reflective platform (i.e. a micromirror) which is supported above a substrate by flexures which can be bent upwards to tilt the platform in any direction over an angle of generally .+-.10 degrees using a gear-driven rack attached to each flexure. Each rack is driven by a rotary microengine (i.e. a micromotor); and an optional thermal actuator can be used in combination with each microengine for initially an initial uplifting of the platform away from the substrate. The MEM apparatus has applications for optical switching (e.g. between a pair of optical fibers) or for optical beam scanning.

  6. Bose-Einstein condensates on tilted lattices: Coherent, chaotic, and subdiffusive dynamics

    SciTech Connect (OSTI)

    Kolovsky, Andrey R.; Gomez, Edgar A.; Korsch, Hans Juergen

    2010-02-15

    The dynamics of a (quasi-) one-dimensional interacting atomic Bose-Einstein condensate in a tilted optical lattice is studied in a discrete mean-field approximation, i.e., in terms of the discrete nonlinear Schroedinger equation. If the static field is varied, the system shows a plethora of dynamical phenomena. In the strong field limit, we demonstrate the existence of (almost) nonspreading states which remain localized on the lattice region populated initially and show coherent Bloch oscillations with fractional revivals in the momentum space (so-called quantum carpets). With decreasing field, the dynamics becomes irregular, however, still confined in configuration space. For even weaker fields, we find subdiffusive dynamics with a wave-packet width growing as t{sup 1/4}.

  7. 2 Tilt recorded by a portable broadband seismograph: The 2003 3 eruption of Anatahan Volcano, Mariana Islands

    E-Print Network [OSTI]

    are highly sensitive to tilt, suggesting that commonly 14 deployed portable broadband seismic sensors may was recorded by a Strekheisen 19 STS-2 seismograph deployed in an underground insulated 20 chamber 7 km west volcano- 24 tectonic (VT) seismicity and is one hour prior to the 25 eruption time estimated

  8. First Flight Tests for a Quadrotor UAV with Tilting Propellers Markus Ryll, Heinrich H. Bulthoff, and Paolo Robuffo Giordano

    E-Print Network [OSTI]

    First Flight Tests for a Quadrotor UAV with Tilting Propellers Markus Ryll, Heinrich H. B¨ulthoff, and Paolo Robuffo Giordano Abstract-- In this work we present a novel concept of a quadrotor UAV show the capabilities of this new UAV concept. I. INTRODUCTION Common UAVs (Unmanned Aerial Vehicles

  9. Tilt Beam Characteristic by Changing Length of Finite-Sized Square Dielectric Substrate of One Arm Rectangular Spiral Antenna

    E-Print Network [OSTI]

    De Flaviis, Franco

    Tilt Beam Characteristic by Changing Length of Finite-Sized Square Dielectric Substrate of One Arm by changing the length of finite-sized square dielectric substrate of one arm rectangular spiral antenna has). Horizontal spiral arm length (HL) is varied from HL=0.8o to HL=5.2o to choose the length that yields

  10. Role of hydrogen-bonding and its interplay with octahedral tilting in CH3NH3PbI3

    E-Print Network [OSTI]

    Lee, Jung-Hoon; Bristowe, Nicholas C.; Bristowe, Paul D.; Cheetham, Anthony K.

    2015-03-05

    First principles calculations on the hybrid perovskite CH3NH3PbI3 predict strong hydrogen-bonding which influences the structure and dynamics of the methylammonium cation and reveal its interaction with the tilting of the PbI6 octahedra...

  11. Rotordynamic coefficients for a load-between-pad, flexible-pivot tilting pad bearing at high loads 

    E-Print Network [OSTI]

    Hensley, John Eric

    2006-10-30

    The dynamic and static performance of a flexure-pivot tilting pad bearing is presented at a load between pad configuration for various load and speed combinations. A similar work performed on the same bearing at lower loads ranging from 0-1 MPa (0...

  12. Measurement of rotordynamic coefficients for a high-speed flexure pivot tilting-pad bearing(load between pad) configuration 

    E-Print Network [OSTI]

    Al-Ghasem, Adnan Mahmoud

    2005-08-29

    . ? ? ? ?? ? ? ? ?? ? ?? ?+ ?? ? ?? ? ? ? ?? ? ?? ?+ ?? ? ?? ? ? ? ?? ? ?? ?= ?? ? ?? ?? y x M M y x C C y x K K f f yy xy yy xy yy xy by bx && && & & In performing a stability analysis of high-speed machinery running on tilting-pad bearings, one would ask if the rotordynamic coefficients should be calculated at the synchronous...

  13. SPERMATOGONIAL STEM CELL RENEWAL FOLLOWING IRRADIATION

    E-Print Network [OSTI]

    Fabrikant, J.I.

    2010-01-01

    continuou-: lnw-l. -vel -,-irradiation for 15 wk, the curvesUnder Continuous Irradiation Cell Cycle Parameter (hr) >J. I. , Pathology of Irradiation, WiTiams and hiHins,

  14. Seasonal and solar cycle variations in high-latitude thermospheric winds

    SciTech Connect (OSTI)

    Aruliah, A.L.; Rees, D. (University Coll., London (United Kingdom)); Steen, A. (Inst. for Rymdfysik, Kiruna (Sweden))

    1991-11-01

    Thermospheric wind measurements have been collected systematically every winter for over nine years from a high-latitude site at Kiruna, Sweden (67.8{degree}N, 20.4{degree}E). The database contains 1,242 nights of data collected with a Fabry-Perot Interferometer (FPI), perhaps the largest single-site database of thermospheric winds. This analysis shows a marked seasonal and solar cycle variation. Particularly at high solar activity, sunward winds of the evening period (16-20 UT) are more than 50% stronger at Spring than at Autumn equinox. This large asymmetry in the behavior of high-latitude thermospheric winds at spring and autumn equinox has not yet been predicted by model simulations.

  15. Multi-Year Lags between Forest Browning and Soil Respiration at High Northern Latitudes

    SciTech Connect (OSTI)

    Bond-Lamberty, Benjamin; Bunn, Andrew G.; Thomson, Allison M.

    2012-11-26

    High-latitude northern ecosystems are experiencing rapid climate changes, and represent a large potential climate feedback because of their high soil carbon densities and shifting disturbance regimes. A significant carbon flow from these ecosystems is soil respiration (RS, the flow of carbon dioxide, generated by plant roots and soil fauna, from the soil surface to atmosphere), and any change in the high-latitude carbon cycle might thus be reflected in RS observed in the field. This study used two variants of a machine-learning algorithm and least squares regression to examine how remotely-sensed canopy greenness (NDVI), climate, and other variables are coupled to annual RS based on 105 observations from 64 circumpolar sites in a global database. The addition of NDVI roughly doubled model performance, with the best-performing models explaining ~62% of observed RS variability

  16. Inhomogeneous structure 0f the high-latitude ionosphere as observed at Norilsk

    E-Print Network [OSTI]

    Lipko, Yu V

    2001-01-01

    In March and August/September 1995, February 1996, and in March-April 1998, observations of the inhomogeneous structure of the high-latitude ionosphere were carried out at Norilsk (geomagnetic latitude and longitude are 64.2 N and 160.4 E, and L=5.2). Small-scale irregularities (with the lifetime of several seconds,and the spatial scale less than 5-7 km), and medium-size wave irregularities(with the period of 10-50 min, and the horizontal size of tens and hundreds of kilometres) of the ionospheric F layer were investigated under different geophysical conditions. A total of 300 hours of observations was recorded, including 250 reflections from the F2 layer, and the other reflections from the sporadic E layer. The diurnal variations of inhomogeneous structure parameters in March and April is obtained. Dependence of some ionospheric irregularity parameters on geomagnetic activity is presented.

  17. MFR PAPER 1135 Irradiation of

    E-Print Network [OSTI]

    the feasibility of combining low-dose ionizing radiation of shrimp with tur- meric and salt as a preservativeMFR PAPER 1135 Irradiation of shrimp extends their storage life. Low Level Ionizing Radiation are eliminated effectively and selectively by low-level doses of irradiation, thereby resulting in extension

  18. 11th HEAD Meeting March 14, 2010 Big Island, Hawaii ChaMPlane Galactic Bulge Latitude

    E-Print Network [OSTI]

    11th HEAD Meeting March 1­4, 2010 Big Island, Hawaii ChaMPlane Galactic Bulge Latitude Survey, Hilo, HI 96720 U.S.A. http://hea-www.harvard.edu/ChaMPlane/ Zhao/CfA ChaMPlane 1 #12;11th HEAD Meeting observation "Limiting Window", a low extinction window closest to the SgrA* with Av=3.9. We also completed

  19. An analysis on the mid-latitude scintillation and coherence frequency bandwidth using transionospheric VHF signals

    SciTech Connect (OSTI)

    Juang, Zhen [Los Alamos National Laboratory; Roussel-dupre, Robert [Los Alamos National Laboratory

    2008-01-01

    An analysis was perfonned on the mid-latitude scintillation and coherence frequency bandwidth (Fcoh) using transionospheric VHF signal data. The data include 1062 events spanning from November 1997 to June 2002. Each event records FORTE satellite received VHF signals from LAPP located at Los Alamos, New Mexico. Fcohs were derived to study scintillation characteristics on diurnal and seasonal variations, as well as changes due to solar and geomagnetic activities. Comparisons to the VHFIUHF coherence frequency bandwidth studies previously reported at equatorial and mid-latitude regions are made using a 4th power frequency dependence relationship. Furthennore, a wideband ionospheric scintillation model, WBMOD, was used to estimate Fcohs and compared with our VHF Fcoh values. Our analysis indicates mid-latitude scintillation characteristics that are not previously revealed. At the VHF bottom frequency range (3035 MHz), distinguished smaller Fcohs are found in time period from sunset to midnight, in wann season from May to August, and in low solar activity years. The effects of geomagnetic storm activity on Fcoh are characterized by a sudden transition at a Kp index of 50-60. Comparisons with median Fcohs estimated from other studies validated our VHF Fcohs for daytime while an order of magnitude larger Fcohs are found for nighttime, implying a time-dependent issue in applying the 4th order power relationship. Furthermore, comparisons with WBMOD-estimated Fcohs indicated generally matched median scintillation level estimates while differences do exist for those events undergoing high geomagnetic stonn activity which may imply underestimates of scintillation level by the WBMOD in the mid-latitude regions.

  20. A statistical characterization of local mid-latitude total electron content

    SciTech Connect (OSTI)

    Gail, W.B.; Prag, A.B. [Aerospace Corp., Los Angeles, CA (United States); Coco, D.S.; Coker, C. [Univ. of Texas, Austin, TX (United States)

    1993-09-01

    The integrated line-of-slight electron density within the ionosphere, known as the total electron content (TEC), is commonly used to quantify ionospheric propagation effects. In order to extrapolate single-point measurements of TEC to other locations and times, some characterization of the TEC spatiotemporal variation must be available. Using a four-channel receiver tracking coded signals from the NAVSTAR Global Positioning System satellites, estimates of both the mean variation and correlation coefficient have been made for the approximately 1200-km or 1-hour local time radius ionospheric region within view of a mid-latitude station. Results were obtained for morning and midday over a 4-week period near the autumnal equinox in 1989. The derived mean variation was found to be well characterized by linear functions of the local time and latitude separation between the ground site and the ionospheric penetration point of the signal. The correlation coefficient during midday was found to decrease linearly with latitude, longitude, and time separation, with values of about 0.91 for a 1000-km separation and 0.98 for a 1-hour separation. During morning hours the longitude and time coefficients were similar to the midday values, but the latitude coefficient was found to have a nonlinear dependence, with values as small as 0.70. The combined results suggest that the decorrelation is due primarily to longer term TEC fluctuation, such as day-to-day variation in the TEC spatial dependence, rather than to transient effects such as traveling ionospheric disturbances. The analysis provides a spatiotemporal characterization of TEC that can be used to extrapolate TEC values from single-point measurements. 13 refs., 8 figs.

  1. Irradiated Materials Examination and Testing Facility (IMET)...

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

    in a laboratory hood or modified glove boxes in the SPL. Applications Physical and mechanical properties testing Examination of irradiated materials Irradiated specimen storage...

  2. Impact of rising greenhouse gases on mid-latitude storm tracks and associated hydroclimate variability and change

    SciTech Connect (OSTI)

    Seager, Richard

    2014-12-08

    Project Summary This project aimed to advance physical understanding of how and why the mid-latitude jet streams and storm tracks shift in intensity and latitude in response to changes in radiative forcing with an especial focus on rising greenhouse gases. The motivation, and much of the work, stemmed from the importance that these mean and transient atmospheric circulation systems have for hydroclimate. In particular drying and expansion of the subtropical dry zones has been related to a poleward shift of the mid-latitude jets and storm tracks. The work involved integrated assessment of observation and model projections as well as targeted model simulations.

  3. Low-latitude Western North Atlantic climate variability during the past millennium : insights from proxies and models

    E-Print Network [OSTI]

    Saenger, Casey Pearce

    2009-01-01

    Estimates of natural climate variability during the past millennium provide a frame of reference in which to assess the significance of recent changes. This thesis investigates new methods of reconstructing low-latitude ...

  4. HH 1158: The lowest luminosity externally irradiated Herbig-Haro jet

    E-Print Network [OSTI]

    Riaz, B

    2015-01-01

    We have identified a new externally irradiated Herbig-Haro (HH) jet, HH 1158, within ~2 pc of the massive OB type stars in the sigma Orionis cluster. At an Lbol ~ 0.1 Lsun, HH 1158 is the lowest luminosity irradiated HH jet identified to date in any cluster. Results from the analysis of high-resolution optical spectra indicate asymmetries in the brightness, morphology, electron density, velocity, and the mass outflow rates for the blue and red-shifted lobes. We constrain the position angle of the HH 1158 jet at 102+/-5 degree. The mass outflow rate and the mean accretion rate for HH 1158 using multiple diagnostics are estimated to be (5.2 +/- 2.6) x 10^(-10) Msun/yr and (3.0 +/- 1.0) x 10^(-10) Msun/yr, respectively. The properties for HH 1158 are notably similar to the externally irradiated HH 444 -- HH 447 jets previously identified in sigma Orionis. In particular, the morphology is such that the weaker jet beam is tilted towards the massive stars, indicating a higher extent of photo-evaporation. The high v...

  5. Vertical profiles of radar reflectivity of convective cells in tropical and mid-latitude mesoscale convective systems 

    E-Print Network [OSTI]

    Lutz, Kurt Reed

    1992-01-01

    VERTICAL PROFILES OF RADAR REFLECTIVITY OF CONVECTIVE CELLS IN TROPICAL AND MID-LATITUDE MESOSCALE CONVECTIVE SYSTEMS A Thesis by KURT REED LUTZ Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 1992 Major Subject: Meteorology VERTICAL PROFILES OF RADAR REFLECTIVITY OF CONVECTIVE CELLS IN TROPICAL AND MID-LATITUDE MESOSCALE CONVECTIVE SYSTEMS A Thesis by KURT REED LUTZ Approved...

  6. Irradiation-induced phenomena in carbon

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Chapter 1 Irradiation-induced phenomena in carbon nanotubes To appear in "Chemistry of Carbon@acclab.helsinki.fi 1 #12;2CHAPTER 1. IRRADIATION-INDUCED PHENOMENA IN CARBON NANOTUBES #12;Contents 1 Irradiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2 Interaction of energetic particles with solid targets . . . . . . . . 6 1.2.1 Ion irradiation

  7. Solar irradiance forecasting at multiple time horizons and novel methods to evaluate uncertainty

    E-Print Network [OSTI]

    Marquez, Ricardo

    2012-01-01

    Solar irradiance data . . . . . . . . . . . . .Irradiance . . . . . . . . . . . . . . . . . . . . . . . . . . .4 Forecasting Solar Irradiance With GOES-West Satellite

  8. A FALSE POSITIVE FOR OCEAN GLINT ON EXOPLANETS: THE LATITUDE-ALBEDO EFFECT

    SciTech Connect (OSTI)

    Cowan, Nicolas B. [Center for Interdisciplinary Exploration and Research in Astrophysics and Department of Physics and Astronomy, Northwestern University, 2131 Tech Drive, Evanston, IL 60208 (United States); Abbot, Dorian S. [Department of Geophysical Sciences, University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637 (United States); Voigt, Aiko [Max Planck Institute for Meteorology, Bundesstr. 53, D-20146, Hamburg (Germany)

    2012-06-10

    Identifying liquid water on the surface of planets is a high priority, as this traditionally defines habitability. One proposed signature of oceans is specular reflection ('glint'), which increases the apparent albedo of a planet at crescent phases. We post-process a global climate model of an Earth-like planet to simulate reflected light curves. Significantly, we obtain glint-like phase variations even though we do not include specular reflection in our model. This false positive is the product of two generic properties: (1) for modest obliquities, a planet's poles receive less orbit-averaged stellar flux than its equator, so the poles are more likely to be covered in highly reflective snow and ice; and (2) we show that reflected light from a modest-obliquity planet at crescent phases probes higher latitudes than at gibbous phases, therefore a planet's apparent albedo will naturally increase at crescent phase. We suggest that this 'latitude-albedo effect' will operate even for large obliquities: in that case the equator receives less orbit-averaged flux than the poles, and the equator is preferentially sampled at crescent phase. Using rotational and orbital color variations to map the surfaces of directly imaged planets and estimate their obliquity will therefore be a necessary pre-condition for properly interpreting their reflected phase variations. The latitude-albedo effect is a particularly convincing glint false positive for zero-obliquity planets, and such worlds are not amenable to latitudinal mapping. This effect severely limits the utility of specular reflection for detecting oceans on exoplanets.

  9. Magnetic particles confined in a modulated channel: structural transitions tunable by tilting a magnetic field

    E-Print Network [OSTI]

    J. E. Galván-Moya; D. Lucena; W. P. Ferreira; F. M. Peeters

    2014-01-03

    The ground state of colloidal magnetic particles in a modulated channel are investigated as function of the tilt angle of an applied magnetic field. The particles are confined by a parabolic potential in the transversal direction while in the axial direction a periodic substrate potential is present. By using Monte Carlo (MC) simulations, we construct a phase diagram for the different crystal structures as a function of the magnetic field orientation, strength of the modulated potential and the commensurability factor of the system. Interestingly, we found first and second order phase transitions between different crystal structures, which can be manipulated by the orientation of the external magnetic field. A re-entrant behavior is found between two- and four-chain configurations, with continuous second order transitions. Novel configurations are found consisting of frozen in solitons. By changing the orientation and/or strength of the magnetic field and/or the strength and the spatial frequency of the periodic substrate potential, the system transits through different phases.

  10. Proton irradiation effect on SCDs

    E-Print Network [OSTI]

    Yan-Ji Yang; Jing-Bin Lu; Yu-Sa Wang; Yong Chen; Yu-Peng Xu; Wei-Wei Cui; Wei Li; Zheng-Wei Li; Mao-Shun Li; Xiao-Yan Liu; Juan Wang; Da-Wei Han; Tian-Xiang Chen; Cheng-Kui Li; Jia Huo; Wei Hu; Yi Zhang; Bo Lu; Yue Zhu; Ke-Yan Ma; Di Wu; Yan Liu; Zi-Liang Zhang; Guo-He Yin; Yu Wang

    2014-04-19

    The Low Energy X-ray Telescope is a main payload on the Hard X-ray Modulation Telescope satellite. The swept charge device is selected for the Low Energy X-ray Telescope. As swept charge devices are sensitive to proton irradiation, irradiation test was carried out on the HI-13 accelerator at the China Institute of Atomic Energy. The beam energy was measured to be 10 MeV at the SCD. The proton fluence delivered to the SCD was $3\\times10^{8}\\mathrm{protons}/\\mathrm{cm}^{2}$ over two hours. It is concluded that the proton irradiation affects both the dark current and the charge transfer inefficiency of the SCD through comparing the performance both before and after the irradiation. The energy resolution of the proton-irradiated SCD is 212 eV@5.9 keV at $-60\\,^{\\circ}\\mathrm{C}$, while it before irradiated is 134 eV. Moreover, better performance can be reached by lowering the operating temperature of the SCD on orbit.

  11. Proton irradiation effect on SCDs

    E-Print Network [OSTI]

    Yang, Yan-Ji; Wang, Yu-Sa; Chen, Yong; Xu, Yu-Peng; Cui, Wei-Wei; Li, Wei; Li, Zheng-Wei; Li, Mao-Shun; Liu, Xiao-Yan; Wang, Juan; Han, Da-Wei; Chen, Tian-Xiang; Li, Cheng-Kui; Huo, Jia; Hu, Wei; Zhang, Yi; Lu, Bo; Zhu, Yue; Ma, Ke-Yan; Wu, Di; Liu, Yan; Zhang, Zi-Liang; Yin, Guo-He; Wang, Yu

    2014-01-01

    The Low Energy X-ray Telescope is a main payload on the Hard X-ray Modulation Telescope satellite. The swept charge device is selected for the Low Energy X-ray Telescope. As swept charge devices are sensitive to proton irradiation, irradiation test was carried out on the HI-13 accelerator at the China Institute of Atomic Energy. The beam energy was measured to be 10 MeV at the SCD. The proton fluence delivered to the SCD was $3\\times10^{8}\\mathrm{protons}/\\mathrm{cm}^{2}$ over two hours. It is concluded that the proton irradiation affects both the dark current and the charge transfer inefficiency of the SCD through comparing the performance both before and after the irradiation. The energy resolution of the proton-irradiated SCD is 212 eV@5.9 keV at $-60\\,^{\\circ}\\mathrm{C}$, while it before irradiated is 134 eV. Moreover, better performance can be reached by lowering the operating temperature of the SCD on orbit.

  12. A Blue Tilt in the Globular Cluster System of the Milky Way-like Galaxy NGC 5170

    E-Print Network [OSTI]

    Forbes, Duncan; Harris, William; Bailin, Jeremy; Strader, Jay; Brodie, Jean; Larsen, Soeren

    2009-01-01

    Here we present HST/ACS imaging, in the B and I bands, of the edge-on Sb/Sc galaxy NGC 5170. Excluding the central disk region region, we detect a 142 objects with colours and sizes typical of globular clusters (GCs). Our main result is the discovery of a `blue tilt' (a mass-metallicity relation), at the 3sigma level, in the metal-poor GC subpopulation of this Milky Way like galaxy. The tilt is consistent with that seen in massive elliptical galaxies and with the self enrichment model of Bailin & Harris. For a linear mass-metallicity relation, the tilt has the form Z ~ L^{0.42 +/- 0.13}. We derive a total GC system population of 600 +/- 100, making it much richer than the Milky Way. However when this number is normalised by the host galaxy luminosity or stellar mass it is similar to that of M31. Finally, we report the presence of a potential Ultra Compact Dwarf of size ~ 6 pc and luminosity M_I ~ -12.5, assuming it is physically associated with NGC 5170.

  13. Experimental frequency-dependent rotordynamic coefficients for a load-on-pad, high-speed, flexible-pivot tilting-pad bearing 

    E-Print Network [OSTI]

    Rodriguez Colmenares, Luis Emigdio

    2004-09-30

    This thesis provides experimental frequency dependent stiffness and damping coefficient results for a high-speed, lightly loaded, flexible-pivot tilting-pad bearing, with a load-on-pad configuration. Test conditions include four shaft speeds (6000...

  14. Experimentally Determine the Impact of Jacking-Oil Pockets on the Rotordynamic Characteristics of a Four-Pad, LBP, Tilting-Pad Journal Bearing 

    E-Print Network [OSTI]

    Kluitenberg, Matthew P

    2015-04-29

    Test results that examine the influence of jacking-oil ports on a tilting pad journal (TPJ) bearing are presented. The static and dynamic characteristics before and after adding jacking-oil ports are compared. The test ...

  15. Latitude survey investigation of galactic cosmic ray solar modulation during 1994-2007

    SciTech Connect (OSTI)

    Nuntiyakul, W.; Ruffolo, D.; Sáiz, A.; Evenson, P.; Bieber, J. W.; Clem, J.; Pyle, R.; Duldig, M. L.; Humble, J. E. E-mail: david.ruf@mahidol.ac.th E-mail: evenson@udel.edu E-mail: clem@bartol.udel.edu E-mail: John.Humble@utas.edu.au

    2014-11-01

    The Galactic cosmic ray spectrum exhibits subtle variations over the 22 yr solar magnetic cycle in addition to the more dramatic variations over the 11 yr sunspot cycle. Neutron monitors are large ground-based detectors that provide accurate measurements of variations in the cosmic ray flux at the top of the atmosphere above the detector. At any given location the magnetic field of the Earth excludes particles below a well-defined rigidity (momentum per unit charge) known as the cutoff rigidity, which can be accurately calculated using detailed models of the geomagnetic field. By carrying a neutron monitor to different locations, e.g., on a ship, the Earth itself serves as a magnet spectrometer. By repeating such latitude surveys with identical equipment, a sensitive measurement of changes in the spectrum can be made. In this work, we analyze data from the 1994 through 2007 series of latitude surveys conducted by the Bartol Research Institute, the University of Tasmania, and the Australian Antarctic Division. We confirm the curious 'crossover' in spectra measured near solar minima during epochs of opposite solar magnetic polarity, and show that it is directly related to a sudden change in the spectral behavior of solar modulation at the time of the polarity reversal, as revealed from contemporaneous variations in the survey data and a fixed station. We suggest that the spectral change and crossover result from the interaction of effects due to gradient/curvature drifts with a systematic change in the interplanetary diffusion coefficient caused by turbulent magnetic helicity.

  16. Simulations of dislocation pile-ups at assymetric tilt boundaries in aluminum

    SciTech Connect (OSTI)

    Valone, Steven [Los Alamos National Laboratory; Wang, Jian M [Los Alamos National Laboratory; Hoagland, Richard C [Los Alamos National Laboratory; Germann, Timothy C [Los Alamos National Laboratory

    2011-01-21

    Materials deformation processes are increasingly approachable through the both conventional and accelerated molecular dynamics. In one deformation process, dislocation pile-up at a grain boundary, a greater understanding is required as to how dislocations transmit through grain boundaries, causing plastic deformation, or reflect and reconstruct the grain boundary, but with no macroscopic deformation. Here dislocation pile-ups in an alwninum bicrystal with an asymmetric tilt grain boundary are simulated atomistically, introducing effects of dislocation interactions beyond linear elastic ones. The observed responses as functions of the number of explicitly modeled dislocations and the magnitude of the applied stress are discussed. Typical conditions for the simulations consist of thermal relaxation room temperature, five active dislocations inserted within a 6.5-million-atom cell, and an additional fourteen dislocations represented within the atomistic simulation by their elastic strain fields. The dislocations are initially distributed according to linear elastic estimates of their positions in a double-ended pile-up from a chosen far-field stress. The whole cell is allowed to relax according to a procedure to be described. In the ensuing simulations, the system is propagated for some substantial period of time (lOs of ps), followed by small increments of strain. After a number of such increments, we observe all of the anticipated events. Usually several of the closest dislocations are absorbed into the grain boundary, resulting in varying amounts of reconstruction. Reflections from the boundary are common and show a strong dependence on sample thickness. Transmission events are seen on both slip systems in the other grain. The particulars of these events will be described as well.

  17. Offset, tilted dipole models of Uranian smooth high-frequency radio emission

    SciTech Connect (OSTI)

    Schweitzer, A.E.; Romig, J.H.; Evans, D.R.; Sawyer, C.B. (Radiophysics, Inc., Boulder, CO (USA)); Warwick, J.W. (Radiophysics, Inc., Boulder, CO (USA) Univ. of Colorado, Boulder (USA))

    1990-09-01

    During the Voyager 2 encounter with Uranus in January 1986, the Planetary Radio Astronomy (PRA) experiment detected a complex pattern of radio emissions. Two types of emissions were seen: smooth and bursty. The smooth emission has been divided into smooth high-frequency (SHF) and smooth low-frequency (SLF) components which are presumed to come from different sources because of their distinctly different characteristics. The SHF component is considered in this paper. The SHF emission has been modeled by many authors on OTD (offset, tilted dipole (Ness et al., 1986)) L shells ranging from 5 to 40. However, the bursts have been modeled at much higher L shells. The authors complete an OTD investigation of the SHF emission at high L shells within the range of the bursty source locations, and present a viable high L shell model. This model has fundamentally the same longitudinally symmetric net emission pattern in space as the L shell 5 model presented in Romig et al. (1987) and Barbosa (1988). However, they were unable to produce an acceptable model on intermediate L shells without restricting source longitude. They discuss the similarities and distinctions between their two models and the models of other authors. They believe that the high L shell model (and others similar to it) cannot account for the observed smoothness and periodicity of the SHF emissions because it has open field lines containing untrapped particles, which should produce more variable emission than that seen in the SHF data. Therefore, the authors prefer models at L shells less than 18, the boundary for closed field lines (Ness et al., 1986). They then discuss and contrast two models within this boundary: the L = 5 model and an L {approx} 12 model by Kaiser et al. (1987) and Farrell and Calvert (1989b). The main distinction between these two models is the longitudinal extent of the source location.

  18. Occlusion-Aware Hessians for Error Control in Irradiance Caching /

    E-Print Network [OSTI]

    Schwarzhaupt, Jorge Andres

    2013-01-01

    5.2 Derivation of the Irradiance Hessian . . 5.3of the translational irradiance gradient. . . . . .1.1.1 Occlusion-Aware Irradiance Hessian . . . . . . . .

  19. High-frequency irradiance fluctuations and geographic smoothing

    E-Print Network [OSTI]

    Lave, Matthew; Kleissl, Jan; Arias-Castro, Ery

    2012-01-01

    of the variability of irradiance and PV power time series1997. Study of areal solar irradiance for analyzing areally-High-frequency irradiance fluctuations and geographic

  20. Tritium Related Material Research -Irradiation Effect on Isotropic...

    Office of Environmental Management (EM)

    Related Material Research -Irradiation Effect on Isotropic Graphite Utilizing Heavy Ion-Irradiation- Tritium Related Material Research -Irradiation Effect on Isotropic Graphite...

  1. Nonlinear broadband photoluminescence of graphene induced by femtosecond laser irradiation

    E-Print Network [OSTI]

    Liu, Wei-Tao

    2011-01-01

    by femtosecond laser irradiation Wei-Tao Liu, 1 S. W. Wu, 2USA Upon femtosecond laser irradiation, a bright, broadbandthe experimental etup. laser irradiation, strong PL signals

  2. Newton's second law versus modified-inertia MOND: a test using the high-latitude effect

    E-Print Network [OSTI]

    A. Yu. Ignatiev

    2008-02-12

    The modified-inertia MOND is an approach that proposes a change in Newton's second law at small accelerations as an alternative to dark matter. Recently it was suggested that this approach can be tested in terrestrial laboratory experiments. One way of doing the test is based on the Static High-Latitude Equinox Modified Inertia (SHLEM) effect: around each equinox date, 2 spots emerge on the Earth where static bodies experience spontaneous displacement due to the violation of Newton's second law required by the modified-inertia MOND. Here, a detailed theory of this effect is developed and estimates of the magnitude of the signal due to the effect are obtained. The expected displacement of a mirror in a gravitational wave interferometer is found to be about 10^{-14} m. Some experimental aspects of the proposal are discussed.

  3. Newton's second law versus modified-inertia MOND: A test using the high-latitude effect

    SciTech Connect (OSTI)

    Ignatiev, A. Yu. [Theoretical Physics Research Institute, Melbourne 3163 (Australia)

    2008-05-15

    The modified-inertia MOND is an approach that proposes a change in Newton's second law at small accelerations as an alternative to dark matter. Recently it was suggested that this approach can be tested in terrestrial laboratory experiments. One way of doing the test is based on the static high-latitude equinox modified-inertia effect: around each equinox date, 2 spots emerge on the Earth where static bodies experience spontaneous displacement due to the violation of Newton's second law required by the modified-inertia MOND. Here, a detailed theory of this effect is developed and estimates of the magnitude of the signal due to the effect are obtained. The expected displacement of a mirror in a gravitational-wave interferometer is found to be about 10{sup -14} m. Some experimental aspects of the proposal are discussed.

  4. The Mid-latitude Continental Convective Clouds (MC3E) Experiment Final Campaign Report

    SciTech Connect (OSTI)

    Jensen, Michael [Brookhaven National Lab. (BNL), Upton, NY (United States); Kollias, Pavlos [McGill Univ., Montreal, QC (Canada); Giangrande, Scott [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-04-01

    The Mid-latitude Continental Convective Clouds Experiment (MC3E) took place from April 22 through June 6, 2011, centered at the ARM Southern Great Plains site (http://www.arm.gov/sites/sgp) in northcentral Oklahoma. MC3E was a collaborative effort between the ARM Climate Research Facility and the National Aeronautics and Space Administration’s (NASA’s) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program. The campaign leveraged the largest ground-based observing infrastructure available in the central United States, including recent upgrades through the American Recovery and Reinvestment Act of 2009, combined with an extensive sounding array, remote sensing and in situ aircraft observations, and additional radar and in situ precipitation instrumentation. The overarching goal of the campaign was to provide a three-dimensional characterization of convective clouds and precipitation for the purpose of improving the representation of convective lifecycle in atmospheric models and the reliability of satellite-based retrievals of precipitation.

  5. Statistical criteria for characterizing irradiance time series.

    SciTech Connect (OSTI)

    Stein, Joshua S.; Ellis, Abraham; Hansen, Clifford W.

    2010-10-01

    We propose and examine several statistical criteria for characterizing time series of solar irradiance. Time series of irradiance are used in analyses that seek to quantify the performance of photovoltaic (PV) power systems over time. Time series of irradiance are either measured or are simulated using models. Simulations of irradiance are often calibrated to or generated from statistics for observed irradiance and simulations are validated by comparing the simulation output to the observed irradiance. Criteria used in this comparison should derive from the context of the analyses in which the simulated irradiance is to be used. We examine three statistics that characterize time series and their use as criteria for comparing time series. We demonstrate these statistics using observed irradiance data recorded in August 2007 in Las Vegas, Nevada, and in June 2009 in Albuquerque, New Mexico.

  6. Quaternary sedimentation and diagenesis in a high-latitude reef, Houtman Abrolhos Islands, Western Australia

    SciTech Connect (OSTI)

    Rosen, M.R.; Collins, L.B. (Curtin Univ. of Technology, Perth, Western Australia (Australia)); Wyrwoll, K.H.; Hatcher, B.G. (Univ. of Western Australia, Perth (Australia))

    1990-05-01

    The Houtman Abrolhos reefs are located 80 km off the west coast of Australia between latitudes 28 and 29{degree} south. The islands are situated on three Pleistocene carbonate reef platforms which rise above the surrounding shelf. The modern coral reefs are close to the geographic limit for coral growth in the southern hemisphere and survive due to the presence of the Leeuwin current (a poleward-flowing warm stream). Two major shallow-water benthic communities coexist in the Abrolhos: a macroalgal-dominated community on the windward platform margins and a coral-dominated community on the leeward margins. These communities overlap-particularly in the platform lagoons, where competition between macroalgae and corals is intense. This interaction has been suggested as a major factor controlling the growth of cord reefs at high latitudes. The Holocene carbonate sediments lack nonskeletal components and are dominated by coral and coralline algal fragments with subordinate molluskan and echinoderm debris. The accumulations can be grouped into the following major facies: (1) coral framestone and coralline algal/serpulid boundstone, (2) submarine sand sheets, (3) subaerial coral storm ridges, (4-) peritidal to subtidal shingle and rubble veneers composed of dominantly coral debris, and (5) eolian dunes and beach sand. The Holocene sediment is a thin (< 2 m) veneer on the Pleistocene reef platform, which is emergent as small islands. The Pleistocene platform is composed of reef facies that can be directly related to the Holocene sediments. The platform is composed of framestone and boundstone facies (corals and coralline algal/serpulid facies), rudstones (submarine coral rubble facies), planar-bedded skeletal grainstones dipping 12-13{degree} (submarine sand sheet and peritidal shingle facies), and large 15-m-high eolianite dunes (eolian dune facies).

  7. Uranium vacancy mobility at the sigma 5 symmetric tilt grain boundary in UO2

    SciTech Connect (OSTI)

    Uberuaga, Blas P.

    2012-05-02

    An important consequence of the fissioning process occurring during burnup is the formation of fission products. These fission products alter the thermo-mechanical properties of the fuel. They also lead to macroscopic changes in the fuel structure, including the formation of bubbles that are connected to swelling of the fuel. Subsequent release of fission gases increase the pressure in the plenum and can cause changes in the properties of the fuel pin itself. It is thus imperative to understand how fission products, and fission gases in particular, behave within the fuel in order to predict the performance of the fuel under operating conditions. Fission gas redistribution within the fuel is governed by mass transport and the presence of sinks such as impurities, dislocations, and grain boundaries. Thus, to understand how the distribution of fission gases evolves in the fuel, we must understand the underlying transport mechanisms, tied to the concentrations and mobilities of defects within the material, and how these gases interact with microstructural features that might act as sinks. Both of these issues have been addressed in previous work under NEAMS. However, once a fission product has reached a sink, such as a grain boundary, its mobility may be different there than in the grain interior and predicting how, for example, bubbles nucleate within grain boundaries necessitates an understanding of how fission gases diffuse within boundaries. That is the goal of the present work. In this report, we describe atomic level simulations of uranium vacancy diffusion in the pressence of a {Sigma}5 symmetric tilt boundary in urania (UO{sub 2}). This boundary was chosen as it is the simplest of the boundaries we considered in previous work on segregation and serves as a starting point for understanding defect mobility at boundaries. We use a combination of molecular statics calculations and kinetic Monte Carlo (kMC) to determine how the mobility of uranium vacancies is altered at this particular grain boundary. Given that the diffusion of fission gases such as Xe are tied to the mobility of uranium vacancies, these results given insight into how fission gas mobility differs at grain boundaries compared to bulk urania.

  8. UK Irradiated Materials Archive Steve Roberts

    E-Print Network [OSTI]

    UK Irradiated Materials Archive Steve Roberts University of Oxford MRF meeting ­ CCFE - 7th July 2015 #12;UK Irradiated Materials Archive Background · Establishment of National Nuclear User Facility exposure · Materials well suited for use in future university-based research programmes #12;UK Irradiated

  9. SIPS: Solar Irradiance Prediction System Stefan Achleitner

    E-Print Network [OSTI]

    Cerpa, Alberto E.

    SIPS: Solar Irradiance Prediction System Stefan Achleitner Computer Science and Engineering the variability and dynamics are the largest. We propose SIPS, Solar Irradiance Prediction System, a novel sensing infrastructure using wireless sensor networks (WSNs) to enable sensing of solar irradiance for solar power

  10. Vol. [VOL], No. [ISS]: 111 Irradiance Rigs

    E-Print Network [OSTI]

    Toronto, University of

    Vol. [VOL], No. [ISS]: 1­11 Irradiance Rigs Hong Yuan UMass Amherst, Disney Interactive Studios that conveys their placement in the environment. Irradiance Volumes [Greger et al. 98] were designed specifically for this problem. The spatially varying irradiance in a volume is explicitly computed

  11. Methane fluxes between terrestrial ecosystems and the atmosphere at northern high latitudes during the past century: A retrospective

    E-Print Network [OSTI]

    McGuire, A. David

    Methane fluxes between terrestrial ecosystems and the atmosphere at northern high latitudes during develop and use a new version of the Terrestrial Ecosystem Model (TEM) to study how rates of methane (CH4 dynamics (3309); 1890 Hydrology: Wetlands; KEYWORDS: methane emissions, methane oxidation, permafrost

  12. Operational taxonomy and (paleo-)autecology of round, brown, spiny dinoflagellate cysts from the Quaternary of high northern latitudes

    E-Print Network [OSTI]

    Pedersen, Tom

    Operational taxonomy and (paleo-)autecology of round, brown, spiny dinoflagellate cysts from determination key taxonomy paleoecology Round brown spiny dinoflagellate cysts from high latitudes a synthesis of descriptions with remarks on the mor- phology, taxonomy, nomenclature and ecology of cysts from

  13. High latitude gravity waves at the Venus cloud tops as observed by the Venus Monitoring Camera on board Venus Express

    E-Print Network [OSTI]

    Spiga, Aymeric

    in VMC images on the base of their morphology: long, medium, short and irregular type waves. With the aim (latitude and longitude), local time, solar zenith angle, packet length and width, orientation, and wavelength of each wave. The long type waves appear as long and nar- row straight features extending more

  14. A jet streak circulation associated with a low-latitude jet in the Southern Hemisphere over Africa.

    E-Print Network [OSTI]

    Nicholson, Sharon E.

    A jet streak circulation associated with a low-latitude jet in the Southern Hemisphere over Africa 2007 #12;2 Abstract In the Southern Hemisphere over Africa a mid-tropospheric easterly jet stream exists during some months that is analogous to the African Easterly Jet over West Africa. In this note

  15. Determination of the optimum inclination of a flat solar collector in function of latitude and local climatic data

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    569 Determination of the optimum inclination of a flat solar collector in function of latitude of a solar collector, it is necessary to reduce its size to a minimum for a given collected energy of equations described in this work were developed to determine the inclination angle of a . flat solar

  16. Testing a theory for the effect of latitude on the persistence of eddy driven jets using CMIP3 simulations

    E-Print Network [OSTI]

    Barnes, Elizabeth A.

    Testing a theory for the effect of latitude on the persistence of eddy driven jets using CMIP3­south shifts in the position of the jet is investigated in 37 CMIP3 integrations over four forcing scenarios. The persistence of the Southern Annular Mode (SAM) decreases when the mean jet is located closer to the pole

  17. Effects of solar wind magnetosphere coupling recorded at different geomagnetic latitudes: Separation of directly-driven and storage/

    E-Print Network [OSTI]

    Lockwood, Mike

    Effects of solar wind magnetosphere coupling recorded at different geomagnetic latitudes: Separation of directly-driven and storage/ release systems I. D. Finch,1 M. L. Lockwood,1,2 and A. P November 2008. [1] The effect on geomagnetic activity of solar wind speed, compared

  18. Solar UV radiation exposure of seamen - Measurements, calibration and model calculations of erythemal irradiance along ship routes

    SciTech Connect (OSTI)

    Feister, Uwe; Meyer, Gabriele; Kirst, Ulrich

    2013-05-10

    Seamen working on vessels that go along tropical and subtropical routes are at risk to receive high doses of solar erythemal radiation. Due to small solar zenith angles and low ozone values, UV index and erythemal dose are much higher than at mid-and high latitudes. UV index values at tropical and subtropical Oceans can exceed UVI = 20, which is more than double of typical mid-latitude UV index values. Daily erythemal dose can exceed the 30-fold of typical midlatitude winter values. Measurements of erythemal exposure of different body parts on seamen have been performed along 4 routes of merchant vessels. The data base has been extended by two years of continuous solar irradiance measurements taken on the mast top of RV METEOR. Radiative transfer model calculations for clear sky along the ship routes have been performed that use satellite-based input for ozone and aerosols to provide maximum erythemal irradiance and dose. The whole data base is intended to be used to derive individual erythemal exposure of seamen during work-time.

  19. Automated Kinematic Modelling of Warped Galaxy Discs in Large Hi Surveys: 3D Tilted Ring Fitting of HI Emission Cubes

    E-Print Network [OSTI]

    Kamphuis, P; Oh, S- H; Spekkens, K; Urbancic, N; Serra, P; Koribalski, B S; Dettmar, R -J

    2015-01-01

    Kinematical parameterisations of disc galaxies, employing emission line observations, are indispensable tools for studying the formation and evolution of galaxies. Future large-scale HI surveys will resolve the discs of many thousands of galaxies, allowing a statistical analysis of their disc and halo kinematics, mass distribution and dark matter content. Here we present an automated procedure which fits tilted-ring models to Hi data cubes of individual, well-resolved galaxies. The method builds on the 3D Tilted Ring Fitting Code (TiRiFiC) and is called FAT (Fully Automated TiRiFiC). To assess the accuracy of the code we apply it to a set of 52 artificial galaxies and 25 real galaxies from the Local Volume HI Survey (LVHIS). Using LVHIS data, we compare our 3D modelling to the 2D modelling methods DiskFit and rotcur. A conservative result is that FAT accurately models the kinematics and the morphologies of galaxies with an extent of eight beams across the major axis in the inclination range 20$^{\\circ}$-90$^{...

  20. RERTR-13 Irradiation Summary Report

    SciTech Connect (OSTI)

    D. M. Perez; M. A. Lillo; G. S. Chang; D. M. Wachs; G. A. Roth; N. E. Woolstenhulme

    2012-09-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-13 was designed to assess performance of different types of neutron absorbers that can be potentially used as burnable poisons in the low enriched uranium-molybdenum based dispersion and monolithic fuels.1 The following report summarizes the life of the RERTR-13 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

  1. Reconciliation of local and long range tilt correlations in underdoped La??xBaxCuO? (0 ? x ? 0.155)

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

    Bozin, Emil S.; Zhong, Ruidan; Knox, Kevin R.; Gu, Genda; Hill, John P.; Tranquada, John M.; Billinge, Simon J. L.

    2015-02-26

    A long standing puzzle regarding the disparity of local and long range CuO? octahedral tilt correlations in the underdoped regime of La??xBaxCuO? is addressed by utilizing complementary neutron powder diffraction and inelastic neutron scattering (INS) approaches. Long-range and static CuO? tilt order with orthogonally inequivalent Cu-O bonds in the CuO? planes in the low temperature tetragonal (LTT) phase is succeeded on warming through the low-temperature transition by one with orthogonally equivalent bonds in the low temperature orthorhombic (LTO) phase. In contrast, the signatures of LTT-type tilts in the instantaneous local atomic structure persist on heating throughout the LTO crystallographic phasemore »on the nanoscale, although becoming weaker as temperature increases. Analysis of the INS spectra for the x = 1/8 composition reveals the dynamic nature of the LTT-like tilt fluctuations within the LTO phase and their 3D character. The doping dependence of relevant structural parameters indicates that the magnitude of the Cu-O bond anisotropy has a maximum at x = 1/8 doping where bulk superconductivity is most strongly suppressed, suggesting that the structural anisotropy might be influenced by electron-phonon coupling and the particular stability of the stripe-ordered phase at this composition. The bond-length modulation that pins stripe order is found to be remarkably subtle, with no anomalous bond length disorder at low temperature, placing an upper limit on any in-plane Cu-O bondlength anisotropy. The results further reveal that although appreciable octahedral tilts persist through the high-temperature transition and into the high temperature tetragonal (HTT) phase, there is no significant preference between different tilt directions in the HTT regime. This study also exemplifies the importance of a systematic approach using complementary techniques when investigating systems exhibiting a large degree of complexity and subtle structural responses.« less

  2. Reconciliation of local and long-range tilt correlations in underdoped La2-xBaxCuO4(0 ? x ? 0.155)

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

    Bozin, Emil S.; Zhong, Ruidan; Knox, Kevin R.; Gu, Genda; Hill, John P.; Tranquada, John M.; Billinge, Simon J. L.

    2015-02-26

    A long standing puzzle regarding the disparity of local and long range CuO? octahedral tilt correlations in the underdoped regime of La??xBaxCuO? is addressed by utilizing complementary neutron powder diffraction and inelastic neutron scattering (INS) approaches. Long-range and static CuO? tilt order with orthogonally inequivalent Cu-O bonds in the CuO? planes in the low temperature tetragonal (LTT) phase is succeeded on warming through the low-temperature transition by one with orthogonally equivalent bonds in the low temperature orthorhombic (LTO) phase. In contrast, the signatures of LTT-type tilts in the instantaneous local atomic structure persist on heating throughout the LTO crystallographic phasemore »on the nanoscale, although becoming weaker as temperature increases. Analysis of the INS spectra for the x = 1/8 composition reveals the dynamic nature of the LTT-like tilt fluctuations within the LTO phase and their 3D character. The doping dependence of relevant structural parameters indicates that the magnitude of the Cu-O bond anisotropy has a maximum at x = 1/8 doping where bulk superconductivity is most strongly suppressed, suggesting that the structural anisotropy might be influenced by electron-phonon coupling and the particular stability of the stripe-ordered phase at this composition. The bond-length modulation that pins stripe order is found to be remarkably subtle, with no anomalous bond length disorder at low temperature, placing an upper limit on any in-plane Cu-O bondlength anisotropy. The results further reveal that although appreciable octahedral tilts persist through the high-temperature transition and into the high temperature tetragonal (HTT) phase, there is no significant preference between different tilt directions in the HTT regime. As a result, this study also exemplifies the importance of a systematic approach using complementary techniques when investigating systems exhibiting a large degree of complexity and subtle structural responses.« less

  3. Is the northern high latitude land-based CO2 sink weakening?

    SciTech Connect (OSTI)

    Mcguire, David [University of Alaska; Kicklighter, David W. [Ecosystem Center, The; Gurney, Kevin R [Arizona State University; Burnside, Todd [University of Alaska, Fairbanks; Melillo, Jerry [Marine Biological Laboratory

    2011-01-01

    Studies indicate that, historically, terrestrial ecosystems of the northern high latitude region may have been responsible for up to 60% of the global net land-based sink for atmospheric CO2. However, these regions have recently experienced remarkable modification of the major driving forces of the carbon cycle, including surface air temperature warming that is significantly greater than the global average and associated increases in the frequency and severity of disturbances. Whether arctic tundra and boreal forest ecosystems will continue to sequester atmospheric CO2 in the face of these dramatic changes is unknown. Here we show the results of model simulations that estimate a 41 Tg C yr-1 sink in the boreal land regions from 1997 to 2006, which represents a 73% reduction in the strength of the sink estimated for previous decades in the late 20th Century. Our results suggest that CO2 uptake by the region in previous decades may not be as strong as previously estimated. The recent decline in sink strength is the combined result of 1) weakening sinks due to warming-induced increases in soil organic matter decomposition and 2) strengthening sources from pyrogenic CO2 emissions as a result of the substantial area of boreal forest burned in wildfires across the region in recent years. Such changes create positive feedbacks to the climate system that accelerate global warming, putting further pressure on emission reductions to achieve atmospheric stabilization targets.

  4. Study of mid-latitude 5577A CI dayglow emissions. Doctoral thesis

    SciTech Connect (OSTI)

    Hume, E.E.

    1992-01-01

    Summary of thesis: The green line (5577angstroms) is a bright, persistent component of the visible airglow. It is produced by an electric quadruple transition from the metastable second excited state (1So) to the first excited state (1D2) of atomic oxygen. These two excited states all lie in the same electron shell of the atom and have the same electron configuration as the ground state of 1s22s22p4, which is the 3P2,1,0. This emission is present in both the daytime and night airglow and in the aurora, and despite a long history of study it is still not fully understood. The emission in the dayglow and the nightglow is relatively homogeneous spatially and global in coverage. In the aurora, the emission is much brighter than the airglow, high structured and very localized being restricted to higher latitudes. The structure of the 5577angstroms emission with altitude and the chemistry responsible for the production of the emission are complex. The vertical structure for the emission has two distinct layers in the airglow each with its own set of production and loss mechanisms. the chemistry for either of these layers is not completely known. The auroral emission is not understood either since it overlaps the upper and lower layer altitudes and it tends to contain some parts of the chemistry of both layers as sources and losses.

  5. Unit-cell thick BaTiO{sub 3} blocks octahedral tilt propagation across oxide heterointerface

    SciTech Connect (OSTI)

    Kan, Daisuke Aso, Ryotaro; Kurata, Hiroki; Shimakawa, Yuichi

    2014-05-14

    We fabricated SrRuO{sub 3}/BaTiO{sub 3}/GdScO{sub 3} heterostructures in which the BaTiO{sub 3} layer is one unit cell thick by pulsed laser deposition and elucidated how the BaTiO{sub 3} layer influences structural and magneto-transport properties of the SrRuO{sub 3} layer through octahedral connections across the heterointerface. Our X-ray-diffraction-based structural characterizations show that while an epitaxial SrRuO{sub 3} layer grown directly on a GdScO{sub 3} substrate is in the monoclinic phase with RuO{sub 6} octahedral tilts, a one-unit-cell-thick BaTiO{sub 3} layer inserted between SrRuO{sub 3} and GdScO{sub 3} stabilizes the tetragonal SrRuO{sub 3} layer with largely reduced RuO{sub 6} tilts. Our high-angle annular dark-field and annular bright-field scanning transmission electron microscopy observations provide an atomic-level view of the octahedral connections across the heterostructure and reveal that the BaTiO{sub 3} layer only one unit cell thick is thick enough to stabilize the RuO{sub 6}-TiO{sub 6} octahedral connections with negligible in-plane oxygen atomic displacements. This results in no octahedral tilts propagating into the SrRuO{sub 3} layer and leads to the formation of a tetragonal SrRuO{sub 3} layer. The magneto-transport property characterizations also reveal a strong impact of the octahedral connections modified by the inserted BaTiO{sub 3} layer on the spin-orbit interaction of the SrRuO{sub 3} layer. The SrRuO{sub 3} layer on BaTiO{sub 3}/ GdScO{sub 3} has in-plane magnetic anisotropy. This is in contrast to the magnetic anisotropy of the monoclinic SrRuO{sub 3} films on the GdScO{sub 3} substrate, in which the easy axis is ?45° to the film surface normal. Our results demonstrate that the one-unit-cell-thick layer of BaTiO{sub 3} can control and manipulate the interfacial octahedral connection closely linked to the structure-property relationship of heterostructures.

  6. Advanced Numerical Weather Prediction Techniques for Solar Irradiance Forecasting : : Statistical, Data-Assimilation, and Ensemble Forecasting

    E-Print Network [OSTI]

    Mathiesen, Patrick James

    2013-01-01

    of numerical weather prediction solar irradiance forecastsof numerical weather prediction solar irradiance forecastsnumerical weather prediction model for solar irradiance

  7. Irradiation preservation of seafood: Literature review

    SciTech Connect (OSTI)

    Molton, P.M.

    1987-10-01

    The application of gamma-irradiation for extending the shelf life of seafood has been of interest for many years. This report reviews a number of studies on seafood irradiation conducted over the past several years. Topics covered include seafood irradiation techniques and dosages, species applicability and differences, the effects of packaging on seafood preservation, and changes in organoleptic acceptability as a result of irradiation. Particular attention is given to radiation effects (likely and unlikely) of concern to the public. These include the potential for generation of toxic chemical products, botulinum toxin production, and other health concerns. No scientifically defensible evidence of any kind was found for any harmful effect of irradiation of seafoods at the doses being considered (less than 300 krad), and all indications are that irradiation is an acceptable and needed additional tool for seafood preservation. 49 refs., 14 figs., 14 tabs.

  8. (Irradiation embrittlement of reactor pressure vessels)

    SciTech Connect (OSTI)

    Corwin, W.R.

    1990-09-24

    The traveler served as a member of the two-man US Nuclear Regulatory Commission sponsored team who visited the Prometey Complex in Leningrad to assess the potential for expanded cooperative research concerning integrity of the primary pressure boundary in commercial light-water reactors. The emphasis was on irradiation embrittlement, structural analysis, and fracture mechanics research for reactor pressure vessels. At the irradiation seminar in Cologne, presentations were made by German, French, Finnish, Russian, and US delegations concerning many aspects of irradiation of pressure vessel steels. The traveler made presentations on mechanisms of irradiation embrittlement and on important aspects of the Heavy-Section Steel Irradiation Program results of irradiated fracture mechanics tests.

  9. Enterprise Assessments, Oak Ridge National Laboratory Irradiated...

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

    of the Safety-Significant Ventilation Systems at the Irradiated Fuels Examination Laboratory Operated by UT-Battelle for the Oak Ridge National Laboratory Office of Science The...

  10. Realistic analytic model for the prompt and high latitude emission in GRBs

    E-Print Network [OSTI]

    F. Genet; J. Granot

    2009-07-15

    Most gamma-ray bursts (GRBs) observed by the Swift satellite show an early rapid decay phase (RDP) in their X-ray lightcurve, which is usually a smooth continuation of the prompt gamma-ray emission, strongly suggesting that it is its tail. However, the mechanism behind it is still not clear. The most popular model for this RDP is High Latitude Emission (HLE). While HLE is expected in many models for the prompt GRB emission, such as the popular internal shocks model, there are models in which it is not expected, such as sporadic magnetic reconnection events. Therefore, testing whether the RDP is consistent with HLE can help distinguish between different prompt emission models. We address this question by modeling the prompt emission as the sum of its individual pulses with their HLE tails. Analytic expressions for the observed flux density are obtained for power-law and Band function emission spectra. For internal shocks the observed instantaneous spectrum is very close to the emitted one, and should be well described by a Band function also during the RDP. Our model naturally produces, the observed spectral softening and steepening of the flux decay. The observed flux during the RDP is initially dominated by the tail of the last pulse, but the tails of one or more earlier pulses can become dominant later on. Moreover, modeling several overlapping pulses as a single wider pulse would over-predict the emission tail. Thus, one should be very careful when testing the predictions of HLE and do a combined temporal and spectral fit of the prompt GRB emission and the RDP.

  11. Radar, satellite, and modelling studies of the low-latitude protonosphere. Ph.D. Thesis

    SciTech Connect (OSTI)

    Gonzalez, S.A.

    1994-01-01

    A study of the variations in the composition of the topside ionosphere at low and equatorial latitudes is presented. Observations of (H+)/n(sub e) are used to study the behavior of the transition altitude over Arecibo during summer solstice for both solar minimum and solar maximum conditions. The solar maximum observations are complemented with DE-2 RPA data from passes over Arecibo to estimate the concentration of helium ions in the topside at that location. The transition altitude over Arecibo is found to be very dependent on solar activity level. For summer solar maximum conditions, the transition altitude varies anywhere from 2000 to 2500 km in altitude during the day (depending on solar flux) down to 1000 km at night. The DE-2 composition data show that during solar maximum conditions, helium ions are an important fraction of the total ionospheric plasma near 900 km over Arecibo with typical concentrations od 1-3 x 10(exp 4) ions cm(sup {minus}3). Observations from the BIMS and RPA instruments aboard the AEE spacecraft are used to study O+, H+, and He+ concentrations in the equatorial topside ionosphere during solar minimum conditions. For these conditions He+ is found to be a minor species and essentially negligible at all times. The transition altitude is found to be near 800 km during the day and below 600 km during the night for all seasons. Finally, the authors present simulations using the University of Sheffield coupled ionosphere thermosphere theoretical model. The results of these simulations are used to try to reproduce their observations and also to study the effect of equatorial E x B drifts on the transition altitude. The model reproduces the major diurnal features in qualitative agreement with the Arecibo solar maximum conditions, the simulations predict peak helium ion concentrations in the topside over Arecibo for equinox with the lowest concentrations occurring during summer solstice.

  12. A study of the daytime E-F sub 1 region ionosphere at mid-latitudes

    SciTech Connect (OSTI)

    Buonsanto, M.J. (Massachusetts Inst. of Tech., Westford (USA))

    1990-06-01

    A photochemical equilibrium daytime model is used to study the ionosphere between 110 and 180 km at mid-latitudes. The model includes the latest photoionization and photoabsorption cross sections, extreme untraviolet (EUV) fluxes in 37 wavelength bands, and all reactions believed to be important in this region. Model results are compared with (1) noon-time E layer critical frequency (foE) at Boulder and Wallops Island over a full solar cycle; (2) Millstone Hill incoherent scatter radar observations of electron density at 180 km (N{sub 180}) for a wide variety of seasons and solar geophysical conditions; (3) selected Millstone Hill incoherent scatter profiles of electron density between 110 and 180 km which included E-F{sub 1} valley minima; and (4) the ratio of the molecular ion concentration to the total ion concentration at 180 km for noon throughout the solar cycle as given by both the IRI-86 ion composition model and the semiempirical ion composition model of Oliver. Best agreement between the photochemical model documented in this paper and the observations and ion composition models is generally obtained if (1) the EUV fluxes in the photochemical model are increased by 25-30% above values derived from published reference spectra; (2) neutral densities used in the photochemical model are decreased by 25% below those given by MSIS-86 at equinox, with larger decreases in winter, and smaller or no decreases in summer. The results show that this region of the ionosphere can be modeled with reasonable success given the current state of knowledge. Modeling this region of the ionosphere is important for resolving ambiguities in true height analysis of ionograms and reduction of incoherent scatter spectra. Improved modeling requires more accurate values of aeronomical parameters, i.e., ionizing fluxes, cross sections, reaction rates, composition and temperature.

  13. Isotopic Evolution of Saline Lakes in the Low-Latitude and Polar Regions

    SciTech Connect (OSTI)

    Horita, Juske [ORNL

    2009-01-01

    Isotopic fractionations associated with two primary processes (evaporation and freezing of water) are discussed, which are responsible for the formation and evolution of saline lakes in deserts from both low-latitude and the Polar regions. In an evaporative system, atmospheric parameters (humidity and isotopic composition of water vapor) have strong influence on the isotopic behavior of saline lakes, and in a freezing system, salinity build-up largely controls the extent of freezing and associated isotope fractionation. In both systems, salinity has a direct impact on the isotopic evolution of saline lakes. It is proposed that a steady-state 'terminal lake' model with short-term hydrologic and environmental perturbations can serve as a useful framework for investigating both evaporative and freezing processes of perennial saline lakes. Through re-assessment of own work and literature data for saline lakes, it was demonstrated that effective uses of the isotope activity compositions of brines and salinity-chemistry data could reveal dynamic changes and evolution in the isotopic compositions of saline lakes in response to hydrologic and environmental changes. The residence time of isotopic water molecules in lakes determines the nature of responses in the isotopic compositions following perturbations in the water and isotope balances (e.g., dilution by inflow, water deficit by increased evaporation, and/or reduction in inflow). The isotopic profiles of some saline lakes from the Polar regions show that they switched the two contrasting modes of operation between evaporative and freezing systems, in response to climate and hydrological changes in the past.

  14. Irradiation test of electrical insulation materials performed at

    E-Print Network [OSTI]

    McDonald, Kirk

    Irradiation test of electrical insulation materials performed at NCBJ, Poland RESMM12- 10 #12;Outlet · EuCARD insulators certification irradiation requirements · Selection of the irradiation source for the sample irradiation purpose · Irradiation cryostat and set-up at NCBJ, Swierk, POLAND

  15. Cluster characters II: A multiplication formula Let C be a Hom-finite triangulated 2-CalabiYau category with a cluster tilting object. Under

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Cluster characters II: A multiplication formula Yann Palu Abstract Let C be a Hom categories of modules over a preprojective algebra of Dynkin type, we prove a multiplication formula for the cluster character associated with any cluster tilting object. This formula generalizes those obtained

  16. PS-wave moveout inversion for tilted TI media: A physical-modeling study Pawan Dewangan and Ilya Tsvankin , Center for Wave Phenomena, Colorado School of Mines (CSM),

    E-Print Network [OSTI]

    PS-wave moveout inversion for tilted TI media: A physical-modeling study Pawan Dewangan and Ilya Tsvankin , Center for Wave Phenomena, Colorado School of Mines (CSM), Mike Batzle, Center for Rock Abuse, CSM, Kasper van Wijk, Physical Acoustics Laboratory, CSM, and Matt Haney, Center for Wave Phenomena

  17. Anisotropic mean-square displacements in two-dimensional colloidal crystals of tilted dipoles V. A. Froltsov, C. N. Likos, and H. Lwen

    E-Print Network [OSTI]

    Likos, Christos N.

    Anisotropic mean-square displacements in two-dimensional colloidal crystals of tilted dipoles V. A the crystal aniso- tropy or not. Here we study an anisotropic two-dimensional colloidal crystal composed; revised manuscript received 7 February 2005; published 31 March 2005 Superparamagnetic colloidal particles

  18. The dependence of stellar mass and angular momentum losses on latitude and on active region and dipolar magnetic fields

    E-Print Network [OSTI]

    Garraffo, Cecilia; Cohen, Ofer

    2015-01-01

    Rotation evolution of late-type stars is dominated by magnetic braking and the underlying factors that control this angular momentum loss are important for the study of stellar spin-down. In this work, we study angular momentum loss as a function of two different aspects of magnetic activity using a calibrated Alfv\\'en wave-driven magnetohydrodynamic wind model: the strengths of magnetic spots and their distribution in latitude. By driving the model using solar and modified solar surface magnetograms, we show that the topology of the field arising from the net interaction of both small-scale and large-scale field is important for spin-down rates and that angular momentum loss is not a simple function of large scale magnetic field strength. We find that changing the latitude of magnetic spots can modify mass and angular momentum loss rates by a factor of two. The general effect that causes these differences is the closing down of large-scale open field at mid- and high-latitudes by the addition of the small-sc...

  19. A Balloon-borne Measurement of High Latitude Atmospheric Neutrons Using a LiCAF Neutron Detector

    E-Print Network [OSTI]

    Kole, Merlin; Fukuda, Kentaro; Ishizu, Sumito; Jackson, Miranda; Kamae, Tune; Kawaguchi, Noriaki; Kawano, Takafumi; Kiss, Mózsi; Moretti, Elena; Salinas, Maria Fernanda Muñoz; Pearce, Mark; Rydström, Stefan; Takahashi, Hiromitsu; Yanagida, Takayuki

    2013-01-01

    PoGOLino is a scintillator-based neutron detector. Its main purpose is to provide data on the neutron flux in the upper stratosphere at high latitudes at thermal and nonthermal energies for the PoGOLite instrument. PoGOLite is a balloon borne hard X-ray polarimeter for which the main source of background stems from high energy neutrons. No measurements of the neutron environment for the planned flight latitude and altitude exist. Furthermore this neutron environment changes with altitude, latitude and solar activity, three variables that will vary throughout the PoGOLite flight. PoGOLino was developed to study the neutron environment and the influences from these three variables upon it. PoGOLino consists of two Europium doped Lithium Calcium Aluminium Fluoride (Eu:LiCAF) scintillators, each of which is sandwiched between 2 Bismuth Germanium Oxide (BGO) scintillating crystals, which serve to veto signals produced by gamma-rays and charged particles. This allows the neutron flux to be measured even in high rad...

  20. Structured Penumbral Irradiance Computation George Drettakis, Eugene Fiume

    E-Print Network [OSTI]

    Toronto, University of

    Structured Penumbral Irradiance Computation George Drettakis, Eugene Fiume Abstract-- A definitive understanding of irradiance behavior in penumbral regions has been hard to come by, mainly due irradiance varies non-monotonically are characterized empirically, and numerical tests are performed

  1. DIFFUSE GALACTIC LIGHT IN THE FIELD OF THE TRANSLUCENT HIGH GALACTIC LATITUDE CLOUD MBM32

    SciTech Connect (OSTI)

    Ienaka, N.; Kawara, K. [Institute of Astronomy, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan)] [Institute of Astronomy, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Matsuoka, Y.; Oyabu, S. [Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan)] [Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan); Sameshima, H. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8501 (Japan)] [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8501 (Japan); Tsujimoto, T. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)] [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Peterson, B. A., E-mail: ienaka@ioa.s.u-tokyo.ac.jp [Research School of Astronomy and Astrophysics, The Australian National University, Weston Creek, ACT 2611 (Australia)

    2013-04-10

    We have conducted B-, g-, V-, and R-band imaging in a 45' Multiplication-Sign 40' field containing part of the high Galactic latitude translucent cloud MBM32, and correlated the intensity of diffuse optical light S{sub {nu}}({lambda}) with that of 100 {mu}m emission S{sub {nu}}(100 {mu}m). A {chi}{sup 2} minimum analysis is applied to fit a linear function to the measured correlation and derive the slope parameter b({lambda}) = {Delta}S{sub {nu}}({lambda})/{Delta}S{sub {nu}}(100 {mu}m) of the best-fit linear function. Compiling a sample by combining our b({lambda}) and published ones, we show that the b({lambda}) strength varies from cloud to cloud by a factor of four. Finding that b({lambda}) decreases as S{sub {nu}}(100 {mu}m) increases in the sample, we suggest that a nonlinear correlation including a quadratic term of S{sub {nu}}(100 {mu}m){sup 2} should be fitted to the measured correlation. The variation of optical depth, which is A{sub V} = 0.16-2.0 in the sample, can change b({lambda}) by a factor of 2-3. There would be some contribution to the large b({lambda}) variation from the forward-scattering characteristic of dust grains which is coupled to the non-isotropic interstellar radiation field (ISRF). Models of the scattering of diffuse Galactic light (DGL) underestimate the b({lambda}) values by a factor of two. This could be reconciled by deficiency in UV photons in the ISRF or by a moderate increase in dust albedo. Our b({lambda}) spectrum favors a contribution from extended red emission (ERE) to the diffuse optical light; b({lambda}) rises from B to V faster than the models, seems to peak around 6000 A and decreases toward long wavelengths. Such a characteristic is expected from the models in which the DGL is combined with ERE.

  2. Methane Fluxes Between Terrestrial Ecosystems and the Atmosphere at Northern High Latitudes During the Past Century: A retrospective analysis with a process-based biogeochemistry model

    E-Print Network [OSTI]

    Zhuang, Qianlai.

    We develop and use a new version of the Terrestrial Ecosystem Model (TEM) to study how rates of methane (CH4) emissions and consumption in high-latitude soils of the Northern Hemisphere have changed over the past century ...

  3. Biomass burning influence on high-latitude tropospheric ozone and reactive nitrogen in summer 2008: a multi-model analysis based on POLMIP simulations

    E-Print Network [OSTI]

    Arnold, S. R.

    We have evaluated tropospheric ozone enhancement in air dominated by biomass burning emissions at high latitudes (> 50° N) in July 2008, using 10 global chemical transport model simulations from the POLMIP multi-model ...

  4. Methods for Post Irradiation Examination of Tritium Producing...

    Office of Environmental Management (EM)

    Methods for Post Irradiation Examination of Tritium Producing Burnable Absorber Rods Methods for Post Irradiation Examination of Tritium Producing Burnable Absorber Rods...

  5. Post Irradiation Examination of Stainless Steel Cladding from...

    Office of Environmental Management (EM)

    Post Irradiation Examination of Stainless Steel Cladding from In-Reactor Permeation Experiment Post Irradiation Examination of Stainless Steel Cladding from In-Reactor Permeation...

  6. RERTR-7 Irradiation Summary Report

    SciTech Connect (OSTI)

    D. M. Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-12-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-7A, was designed to test several modified fuel designs to target fission densities representative of a peak low enriched uranium (LEU) burnup in excess of 90% U-235 at peak experiment power sufficient to generate a peak surface heat flux of approximately 300 W/cm2. The RERTR-7B experiment was designed as a high power test of 'second generation' dispersion fuels at peak experiment power sufficient to generate a surface heat flux on the order of 230 W/cm2.1 The following report summarizes the life of the RERTR-7A and RERTR-7B experiments through end of irradiation, including as-run neutronic analyses, thermal analyses and hydraulic testing results.

  7. The Irradiance Volume Gene Greger , Peter Shirley y, Philip M. Hubbard z, Donald P. Greenberg

    E-Print Network [OSTI]

    Shirley, Peter

    The Irradiance Volume Gene Greger , Peter Shirley y, Philip M. Hubbard z, Donald P. Greenberg quantity irradiance. We call this representation the irradiance volume. Although irradiance. The irradiance volume supports the reconstruction of believable approximations to the illumination in situations

  8. Irradiation of insulators for Workshop on Accelerator Magnet, Superconductor, Design and Optimization

    E-Print Network [OSTI]

    McDonald, Kirk

    Irradiation of insulators for EuCARD Workshop on Accelerator Magnet, Superconductor, Design #12;Outline WAMSDO ­ 14.11.2011 CERN · Motivation of launching EUCARD irradiation task · Irradiation methodology · Post irradiation tests ­ Electrical ­ Thermal ­ Mechanical · Irradiation cryostat · Conclusions

  9. Measuring Degradation Rates Without Irradiance Data

    SciTech Connect (OSTI)

    Pulver, S.; Cormode, D.; Cronin, A.; Jordan, D.; Kurtz, S.; Smith, R.

    2011-02-01

    A method to report PV system degradation rates without using irradiance data is demonstrated. First, a set of relative degradation rates are determined by comparing daily AC final yields from a group of PV systems relative to the average final yield of all the PV systems. Then, the difference between relative and absolute degradation rates is found from a statistical analysis. This approach is verified by comparing to methods that utilize irradiance data. This approach is significant because PV systems are often deployed without irradiance sensors, so the analysis method described here may enable measurements of degradation using data that were previously thought to be unsuitable for degradation studies.

  10. Gamma-ray irradiated polymer optical waveguides

    SciTech Connect (OSTI)

    Lai, C.-C.; Wei, T.-Y.; Chang, C.-Y.; Wang, W.-S.; Wei, Y.-Y.

    2008-01-14

    Optical waveguides fabricated by gamma-ray irradiation on polymer through a gold mask are presented. The gamma-ray induced index change is found almost linearly dependent on the dose of the irradiation. And the measured propagation losses are low enough for practical application. Due to the high penetrability of gamma ray, uniform refractive index change in depth can be easily achieved. Moreover, due to large-area printing, the uniformity of waveguide made by gamma-ray irradiation is much better than that by e-beam direct writing.

  11. Effect of electron-density gradients on propagation of radio waves in the mid-latitude trough. Master's thesis

    SciTech Connect (OSTI)

    Citrone, P.J.

    1991-01-01

    Partial contents of this thesis include: (1) Radio-wave propagation and the mid-latitude trough; (2) Ionospheric measurements; (3) Modification of time-dependent ionospheric model output with latitudinal electron-density profiles from digisonde trough depictions; (4) Ray-tracing simulations to examine ground range; and (5) Effects of three-dimensional gradients in electron density on radio-wave propagation in the trough region. Data is tabulated for geophysical conditions, solar activity level, geomagnetic activity level, conditions for vertical ray refraction to surface, and ray-tracing fixed-input conditions.

  12. A novel facility for 3D micro-irradiation of living cells in a controlled environment by MeV ions

    SciTech Connect (OSTI)

    Mäckel, V. Meissl, W.; Ikeda, T.; Meissl, E.; Kobayashi, T.; Kojima, T. M.; Ogiwara, K.; Yamazaki, Y.; Clever, M.; Imamoto, N.

    2014-01-15

    We present a novel facility for micro-irradiation of living targets with ions from a 1.7 MV tandem accelerator. We show results using 1 MeV protons and 2 MeV He{sup 2+}. In contrast to common micro-irradiation facilities, which use electromagnetic or electrostatic focusing and specially designed vacuum windows, we employ a tapered glass capillary with a thin end window, made from polystyrene with a thickness of 1–2 ?m, for ion focusing and extraction. The capillary is connected to a beamline tilted vertically by 45°, which allows for easy immersion of the extracted ions into liquid environment within a standard cell culture dish. An inverted microscope is used for simultaneously observing the samples as well as the capillary tip, while a stage-top incubator provides an appropriate environment for the samples. Furthermore, our setup allows to target volumes in cells within a ?m{sup 3} resolution, while monitoring the target in real time during and after irradiation.

  13. Generation of short gamma-ray pulses on electron bunches formed in intense interfering laser beams with tilted fronts

    SciTech Connect (OSTI)

    Korobkin, V V; Romanovskiy, M Yu; Trofimov, V A; Shiryaev, O B

    2014-05-30

    It is shown that in the interference of multiple laser pulses with a relativistic intensity, phase and amplitude fronts of which are tilted at an angle with respect to their wave vector, effective traps of charged particles, which are moving at the velocity of light, are formed. Such traps are capable of capturing and accelerating the electrons produced in the ionisation of low-density gas by means of laser radiation. The accelerated electrons in the traps form a bunch, whose dimensions in all directions are much smaller than the laser radiation wavelength. Calculations show that the energy of accelerated electrons may amount to several hundred GeV at experimentally accessible relativistic laser intensities. As a result of the inverse Compton scattering, gamma-quanta with a high energy and narrow radiation pattern are emitted when these electrons interact with a laser pulse propagating from the opposite direction. The duration of emitted gamma-ray pulses constitutes a few attoseconds. The simulation is performed by solving the relativistic equation of motion for an electron with a relevant Lorentz force. (interaction of radiation with matter)

  14. Automatic recovery of missing amplitudes and phases in tilt-limited electron crystallography of two-dimensional crystals

    SciTech Connect (OSTI)

    Gipson, Bryant R.; Stahlberg, Henning [Center for Cellular Imaging and Nano Analytics (C-CINA), Biozentrum, University Basel, WRO-1058 Mattenstrasse 26, CH-4058 Basel (Switzerland); Masiel, Daniel J.; Browning, Nigel D. [Department of Chemical Engineering and Materials Sciences, University of California at Davis, Davis, California 95616 (United States); Spence, John [Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States); Mitsuoka, Kaoru [Biomedicinal Information Research Center (BIRC), National Institute of Advanced Industrial Science and Technology (AIST), 2-3-26, Aomi, Koto-ku, Tokyo 135-0064 (Japan)

    2011-07-15

    Electron crystallography of 2D protein crystals provides a powerful tool for the determination of membrane protein structure. In this method, data is acquired in the Fourier domain as randomly sampled, uncoupled, amplitudes and phases. Due to physical constraints on specimen tilting, those Fourier data show a vast un-sampled ''missing cone'' of information, producing resolution loss in the direction perpendicular to the membrane plane. Based on the flexible language of projection onto sets, we provide a full solution for these problems with a projective constraint optimization algorithm that, for sufficiently oversampled data, produces complete recovery of unmeasured data in the missing cone. We apply this method to an experimental data set of Bacteriorhodopsin and show that, in addition to producing superior results compared to traditional reconstruction methods, full, reproducible, recovery of the missing cone from noisy data is possible. Finally, we present an automatic implementation of the refinement routine as open source, freely distributed, software that will be included in our 2dx software package.

  15. Magnetic rotation (MR) band crossing in N=78 odd-Z nuclei: Tilted axis cranking (TAC) calculations to explore the role of nucleons

    SciTech Connect (OSTI)

    Kumar, Suresh

    2014-08-14

    Magnetic Rotation (MR) band crossing is studied systematically in N=78 isotones (La, Pr, Pm and Eu) using Tilted Axis Cranking (TAC) model. The observables such as I(¯h) vs ¯h?, excitation energy E(MeV) vs spin I(¯h), and the B(M1)/B(E2) vs I(¯h) were considered to pinpoint MR crossing in these nuclei. The results of tilted axis cranking were compared with these experimental observables. The B(M1) and B(E2) values were also reported and used to understand the crossing behaviour of these MR bands. The systematic evolution of this phenomenon in N=78 odd-Z istotones leads to understand the role of nucleons in MR band crossing.

  16. Mechanism of genotoxicity induced by targeted cytoplasmic irradiation

    E-Print Network [OSTI]

    Mechanism of genotoxicity induced by targeted cytoplasmic irradiation M Hong1,2 , A Xu1,3 , H Zhou1 irradiation should not be ignored in radiation risk estimation. Although targeted cytoplasmic irradiation has precision was used to study mechanisms involved in mediating the genotoxic effects in irradiated human

  17. Selective irradiation of the vascular endothelium

    E-Print Network [OSTI]

    Schuller, Bradley W

    2007-01-01

    We developed a unique methodology to selectively irradiate the vascular endothelium in vivo to better understand the role of vascular damage in causing normal tissue radiation side-effects.The relationship between vascular ...

  18. Estimating solar irradiance using a geostationary satellite

    E-Print Network [OSTI]

    Urquhart, Bryan Glenn

    2011-01-01

    from meteorological satellite data. Solar Energy 37, 31–39.specific irradiance data. Solar Energy 60, 89–96. Perez R. ,16 independent data banks. Solar Energy 80, 468–478 Kasten

  19. Neutron Irradiation Resistance of RAFM Steels

    SciTech Connect (OSTI)

    Gaganidze, Ermile; Dafferner, Bernhard; Aktaa, Jarir

    2008-07-01

    The neutron irradiation resistance of the reduced-activation ferritic/martensitic (RAFM) steel EUROFER97 and international reference steels (F82H-mod, OPTIFER-Ia, GA3X and MANET-I) have been investigated after irradiation in the Petten High Flux Reactor up to 16.3 dpa at different irradiation temperatures (250-450 deg. C). The embrittlement behavior and hardening are investigated by instrumented Charpy-V tests with sub-size specimens. Neutron irradiation-induced embrittlement and hardening of EUROFER97 was studied under different heat treatment conditions. Embrittlement and hardening of as-delivered EUROFER97 steel are comparable to those of reference steels. Heat treatment of EUROFER97 at a higher austenitizing temperature substantially improves the embrittlement behaviour at low irradiation temperatures. Analysis of embrittlement vs. hardening behavior of RAFM steels within a proper model in terms of the parameter C={delta}DBTT/{delta}{sigma} indicates hardening-dominated embrittlement at irradiation temperatures below 350 deg. C with 0.17 {<=} C {<=} 0.53 deg. C/MPa. Scattering of C at irradiation temperatures above 400 deg. C indicates non hardening embrittlement. A role of He in a process of embrittlement is investigated in EUROFER97 based steels, that are doped with different contents of natural B and the separated {sup 10}B-isotope (0.008-0.112 wt.%). Testing on small scale fracture mechanical specimens for determination of quasi-static fracture toughness will be also presented in a view of future irradiation campaigns. (authors)

  20. Gamma irradiation effects in W films

    SciTech Connect (OSTI)

    Claro, Luiz H.; Santos, Ingrid A.; Silva, Cassia F.

    2013-05-06

    Using the van Der Pauw methodology, the surface resistivity of irradiated tungsten films deposited on Silicon substrate was measured. The films were exposed to {gamma} radiation using a isotopic {sup 60}Co source in three irradiation stages attaining 40.35 kGy in total dose. The obtained results for superficial resistivity display a time annealing features and their values are proportional to the total dose.

  1. Options for improving the load matching capability of distributed photovoltaics: Methodology and application to high-latitude data

    SciTech Connect (OSTI)

    Widen, Joakim; Waeckelgaard, Ewa; Lund, Peter D.

    2009-11-15

    At high latitudes, domestic electricity demand and insolation are negatively correlated on both an annual and a diurnal basis. With increasing integration of distributed photovoltaics (PV) in low-voltage distribution grids of residential areas, limits to the penetration level are set by voltage rise due to unmatched production and load. In this paper a methodology for determining the impacts of three options for increased load matching is presented and applied to high-latitude data. The studied options are PV array orientation, demand side management (DSM) and electricity storage. Detailed models for domestic electricity demand and PV output are used. An optimisation approach is applied to find an optimal distribution of PV systems on different array orientations and a best-case evaluation of DSM and a storage model are implemented. At high penetration levels, storage is the most efficient option for maximising the solar fraction, but at lower overproduction levels, the impact of DSM is equal or slightly better. An east-west orientation of PV arrays is suggested for high penetration levels, but the effect of the optimised orientation is small. Without an optimised storage operation, the overproduced power is more efficiently reduced by DSM than storage, although this is highly dependent on the applied DSM algorithm. Further research should be focused on the DSM potential and optimal operation of storage. (author)

  2. Irradiated Nuclear Fuel Management: Resource Versus Waste

    SciTech Connect (OSTI)

    Nash, Kenneth L.; Lumetta, Gregg J.; Vienna, John D.

    2013-01-01

    Management of irradiated fuel is an important component of commercial nuclear power production. Although it is broadly agreed that the disposition of some fraction of the fuel in geological repositories will be necessary, there is a range of options that can be considered that affect exactly what fraction of material will be disposed in that manner. Furthermore, until geological repositories are available to accept commercial irradiated fuel, these materials must be safely stored. Temporary storage of irradiated fuel has traditionally been conducted in storage pools, and this is still true for freshly discharged fuel. Criticality control technologies have led to greater efficiencies in packing of irradiated fuel into storage pools. With continued delays in establishing permanent repositories, utilities have begun to move some of the irradiated fuel inventory into dry storage. Fuel cycle options being considered worldwide include the once-through fuel cycle, limited recycle in which U and Pu are recycled back to power reactors as mixed oxide fuel, and advance partitioning and transmutation schemes designed to reduce the long term hazards associated with geological disposal from millions of years to a few hundred years. Each of these options introduces specific challenges in terms of the waste forms required to safely immobilize the hazardous components of irradiated fuel.

  3. Summary Pinus taeda L. stomata respond slowly to changes in irradiance. Because incident irradiance on a leaf varies

    E-Print Network [OSTI]

    Teskey, Robert O.

    Summary Pinus taeda L. stomata respond slowly to changes in irradiance. Because incident irradiance on a leaf varies constantly, the rate of change in stomatal conductance to fluc- tuating irradiance may have with very different irradiance patterns, assuming that rates of stomatal opening and closing were similar

  4. A 24-h forecast of solar irradiance using artificial neural network: Application for performance prediction of a grid-connected PV plant at Trieste, Italy

    SciTech Connect (OSTI)

    Mellit, Adel; Pavan, Alessandro Massi

    2010-05-15

    Forecasting of solar irradiance is in general significant for planning the operations of power plants which convert renewable energies into electricity. In particular, the possibility to predict the solar irradiance (up to 24 h or even more) can became - with reference to the Grid Connected Photovoltaic Plants (GCPV) - fundamental in making power dispatching plans and - with reference to stand alone and hybrid systems - also a useful reference for improving the control algorithms of charge controllers. In this paper, a practical method for solar irradiance forecast using artificial neural network (ANN) is presented. The proposed Multilayer Perceptron MLP-model makes it possible to forecast the solar irradiance on a base of 24 h using the present values of the mean daily solar irradiance and air temperature. An experimental database of solar irradiance and air temperature data (from July 1st 2008 to May 23rd 2009 and from November 23rd 2009 to January 24th 2010) has been used. The database has been collected in Trieste (latitude 45 40'N, longitude 13 46'E), Italy. In order to check the generalization capability of the MLP-forecaster, a K-fold cross-validation was carried out. The results indicate that the proposed model performs well, while the correlation coefficient is in the range 98-99% for sunny days and 94-96% for cloudy days. As an application, the comparison between the forecasted one and the energy produced by the GCPV plant installed on the rooftop of the municipality of Trieste shows the goodness of the proposed model. (author)

  5. Model for the low-latitude ionosphere with coefficients for different seasonal and solar cycle conditions. Final report, 1 October 1981-30 June 1986

    SciTech Connect (OSTI)

    Mendillo, M.; Herniter, B.

    1986-11-01

    A new ionospheric model for the low-latitude ionosphere was constructed to provide easy access to electron density profiles (Ne(h)), total electron content (TEC) and 6300A airglow under a variety of conditions. Results from the rigorous theoretical calculations for ionospheric structure at a given time and a site were parameterized to a set of six coefficients that reproduce the individual Ne(h) profiles using a simple algebraic formula. This report summarizes the rationale for such a model, describes the input parameters and methods used to generate the coefficients, and provides a comprehensive set of coefficients. The model covers the low-latitude ionosphere (24 N to 24 S every 4 deg of dip latitude), over the altitude range 180 to 1000km, for every hour of local time. The tabulated coefficients, TEC and 6300 airglow are presented for three seasons (Equinox, June solstice, and December solstice) and two solar cycles (solar maximum and solar minimum).

  6. Effect of neutron irradiation on vanadium alloys

    SciTech Connect (OSTI)

    Braski, D.N.

    1986-01-01

    Neutron-irradiated vanadium alloys were evaluated for their susceptibility to irradiation hardening, helium embrittlement, swelling, and residual radioactivity, and the results were compared with those for the austenitic and ferritic stainless steels. The VANSTAR-7 and V-15Cr-5Ti alloys showed the greatest hardening between 400 and 600/sup 0/C while V-3Ti-1Si and V-20Ti had lower values that were comparable to those of ferritic steels. The V-15Cr-5Ti and VANSTAR-7 alloys were susceptible to helium embrittlement caused by the combination of weakened grain boundaries and irradiation-hardened grain matrices. Specimen fractures were entirely intergranular in the most severe instances of embrittlement. The V-3Ti-1Si and V-20Ti alloys were more resistant to helium embrittlement. Except for VANSTAR-7 irradiated to 40 dpa at 520/sup 0/C, all of the vanadium alloys exhibited low swelling that was similar to the ferritic steels. Swelling was greater in specimens that were preimplanted with helium using the tritium trick. The vanadium alloys clearly exhibit lower residual radioactivity after irradiation than the ferrous alloys.

  7. Review of recent irradiation-creep results

    SciTech Connect (OSTI)

    Coghlan, W.A.

    1982-05-01

    Materials deform faster under stress in the presence of irradiation by a process known as irradiation creep. This phenomenon is important to reactor design and has been the subject of a large number of experimental and theoretical investigations. The purpose of this work is to review the recent experimental results to obtain a summary of these results and to determine those research areas that require additional information. The investigations have been classified into four subgroups based on the different experimental methods used. These four are: (1) irradiation creep using stress relaxation methods, (2) creep measurements using pressurized tubes, (3) irradiation creep from constant applied load, and (4) irradiation creep experiments using accelerated particles. The similarity and the differences of the results from these methods are discussed and a summary of important results and suggested areas for research is presented. In brief, the important results relate to the dependence of creep on swelling, temperature, stress state and alloying additions. In each of these areas new results have been presented and new questions have arisen which require further research to answer. 65 references.

  8. Intra-hour Direct Normal Irradiance solar forecasting using genetic programming

    E-Print Network [OSTI]

    Queener, Benjamin Daniel

    2012-01-01

    4 2.1 Irradiance Data . . . . . . . . . . . . . . . . . . .24 Figure 4.3: Irradiance Instruments Figure 4.4: Training8 Figure 4.1: Irradiance Input Graph . . . . . . . . .

  9. Advanced Numerical Weather Prediction Techniques for Solar Irradiance Forecasting : : Statistical, Data-Assimilation, and Ensemble Forecasting

    E-Print Network [OSTI]

    Mathiesen, Patrick James

    2013-01-01

    weather prediction solar irradiance forecasts in the US.2013: Review of solar irradiance forecasting methods and asatellite-derived irradiances: Description and validation.

  10. Modeling Total Solar Irradiance Variations Using Automated Classification Software on Mount Wilson Data

    E-Print Network [OSTI]

    Ulrich, R. K.; Parker, D.; Bertello, L.; Boyden, J.

    2010-01-01

    Star: Solar and Stellar Irradiance Variations, IAU Colloq.4 Modeling Total Solar Irradiance Variations Using Automatedcorrelated with total solar irradiance (TSI) to yield a set

  11. A high-resolution, cloud-assimilating numerical weather prediction model for solar irradiance forecasting

    E-Print Network [OSTI]

    Mathiesen, Patrick; Collier, Craig; Kleissl, Jan

    2013-01-01

    of the WRF model solar irradiance forecasts in Andalusia (Beyer, H. , 2009.    Irradiance forecasting for the power dependent probabilistic irradiance  forecasts for coastal 

  12. Analyzing and simulating the variability of solar irradiance and solar PV powerplants

    E-Print Network [OSTI]

    Lave, Matthew S.

    2012-01-01

    Hemker, T. Hoff, Short-term irradiance variability: StationLorenzo, D. Alvira, E. Izco, From irradiance to output power46 High Frequency Irradiance Fluctuations and Geographic

  13. Surface finishing of die and tool steels via plasma-based electron beam irradiation

    E-Print Network [OSTI]

    Yu, Z; WANG, ZHIGANG; Yamazaki, Kazuo; Sano, S

    2006-01-01

    large-area electron beam irradiation, Precision Engineeringof craters. 5. PBEB irradiation process improves corrosionthe case study, PBEB irradiation would be a new potential

  14. THE EFFECTS OF TEMPERATURE AND IMPURITIES ON THE ATOMIC DISPLACEMENT ENERGY DURING ELECTRON IRRADIATION

    E-Print Network [OSTI]

    Drosd, R.M.

    2010-01-01

    ENERGY DURING ELECTRON IRRADIATION Robert Michael DrosdTemperature Changes in I~1 Irradiations. ExperimentalCharged Particle S~osium Irradiations, in Proceedings of a

  15. Meta-analysis of high-latitude nitrogen-addition and warming studies imply ecological mechanisms overlooked by land models

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

    Bouskill, N. J.; Riley, W. J.; Tang, J.

    2014-08-18

    Accurate representation of ecosystem processes in land models is crucial for reducing predictive uncertainty in energy and greenhouse gas feedbacks with the atmosphere. Here we describe an observational and modeling meta-analysis approach to benchmark land models, and apply the method to the land model CLM4.5 with two versions of belowground biogeochemistry. We focused our analysis on the above and belowground high-latitude ecosystem responses to warming and nitrogen addition, and identified mechanisms absent, or poorly parameterized in CLM4.5. While the two model versions predicted similar trajectories for soil carbon stocks following both types of perturbation, other variables (e.g., belowground respiration) differedmore »from the observations in both magnitude and direction, indicating the underlying mechanisms are inadequate for representing high-latitude ecosystems. The observational synthesis attribute these differences to missing representations of microbial dynamics, characterization of above and belowground functional processes, and nutrient competition. We use the observational meta-analyses to discuss potential approaches to improving the current models (e.g., the inclusion of dynamic vegetation or different microbial functional guilds), however, we also raise a cautionary note on the selection of data sets and experiments to be included in a meta-analysis. For example, the concentrations of nitrogen applied in the synthesized field experiments (average =72 kg ha-1 yr-1) are many times higher than projected soil nitrogen concentrations (from nitrogen deposition and release during mineralization), which preclude a rigorous evaluation of the model responses to nitrogen perturbation. Overall, we demonstrate here that elucidating ecological mechanisms via meta-analysis can identify deficiencies in both ecosystem models and empirical experiments.« less

  16. Meta-analysis of high-latitude nitrogen-addition and warming studies implies ecological mechanisms overlooked by land models

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

    Bouskill, N. J.; Riley, W. J.; Tang, J. Y.

    2014-12-11

    Accurate representation of ecosystem processes in land models is crucial for reducing predictive uncertainty in energy and greenhouse gas feedbacks with the climate. Here we describe an observational and modeling meta-analysis approach to benchmark land models, and apply the method to the land model CLM4.5 with two versions of belowground biogeochemistry. We focused our analysis on the aboveground and belowground responses to warming and nitrogen addition in high-latitude ecosystems, and identified absent or poorly parameterized mechanisms in CLM4.5. While the two model versions predicted similar soil carbon stock trajectories following both warming and nitrogen addition, other predicted variables (e.g., belowgroundmore »respiration) differed from observations in both magnitude and direction, indicating that CLM4.5 has inadequate underlying mechanisms for representing high-latitude ecosystems. On the basis of observational synthesis, we attribute the model–observation differences to missing representations of microbial dynamics, aboveground and belowground coupling, and nutrient cycling, and we use the observational meta-analysis to discuss potential approaches to improving the current models. However, we also urge caution concerning the selection of data sets and experiments for meta-analysis. For example, the concentrations of nitrogen applied in the synthesized field experiments (average = 72 kg ha-1 yr-1) are many times higher than projected soil nitrogen concentrations (from nitrogen deposition and release during mineralization), which precludes a rigorous evaluation of the model responses to likely nitrogen perturbations. Overall, we demonstrate that elucidating ecological mechanisms via meta-analysis can identify deficiencies in ecosystem models and empirical experiments.« less

  17. Heavy ion irradiation of crystalline water ice

    E-Print Network [OSTI]

    Dartois, E; Boduch, P; Brunetto, R; Chabot, M; Domaracka, A; Ding, J J; Kamalou, O; Lv, X Y; Rothard, H; da Silveira, E F; Thomas, J C

    2015-01-01

    Under cosmic irradiation, the interstellar water ice mantles evolve towards a compact amorphous state. Crystalline ice amorphisation was previously monitored mainly in the keV to hundreds of keV ion energies. We experimentally investigate heavy ion irradiation amorphisation of crystalline ice, at high energies closer to true cosmic rays, and explore the water-ice sputtering yield. We irradiated thin crystalline ice films with MeV to GeV swift ion beams, produced at the GANIL accelerator. The ice infrared spectral evolution as a function of fluence is monitored with in-situ infrared spectroscopy (induced amorphisation of the initial crystalline state into a compact amorphous phase). The crystalline ice amorphisation cross-section is measured in the high electronic stopping-power range for different temperatures. At large fluence, the ice sputtering is measured on the infrared spectra, and the fitted sputtering-yield dependence, combined with previous measurements, is quadratic over three decades of electronic ...

  18. Horizontal modular dry irradiated fuel storage system

    DOE Patents [OSTI]

    Fischer, Larry E. (Los Gatos, CA); McInnes, Ian D. (San Jose, CA); Massey, John V. (San Jose, CA)

    1988-01-01

    A horizontal, modular, dry, irradiated fuel storage system (10) includes a thin-walled canister (12) for containing irradiated fuel assemblies (20), which canister (12) can be positioned in a transfer cask (14) and transported in a horizontal manner from a fuel storage pool (18), to an intermediate-term storage facility. The storage system (10) includes a plurality of dry storage modules (26) which accept the canister (12) from the transfer cask (14) and provide for appropriate shielding about the canister (12). Each module (26) also provides for air cooling of the canister (12) to remove the decay heat of the irradiated fuel assemblies (20). The modules (26) can be interlocked so that each module (26) gains additional shielding from the next adjacent module (26). Hydraulic rams (30) are provided for inserting and removing the canisters (12) from the modules (26).

  19. Understanding the Irradiation Behavior of Zirconium Carbide

    SciTech Connect (OSTI)

    Motta, Arthur; Sridharan, Kumar; Morgan, Dane; Szlufarska, Izabela

    2013-10-11

    Zirconium carbide (ZrC) is being considered for utilization in high-temperature gas-cooled reactor fuels in deep-burn TRISO fuel. Zirconium carbide possesses a cubic B1-type crystal structure with a high melting point, exceptional hardness, and good thermal and electrical conductivities. The use of ZrC as part of the TRISO fuel requires a thorough understanding of its irradiation response. However, the radiation effects on ZrC are still poorly understood. The majority of the existing research is focused on the radiation damage phenomena at higher temperatures (>450{degree}C) where many fundamental aspects of defect production and kinetics cannot be easily distinguished. Little is known about basic defect formation, clustering, and evolution of ZrC under irradiation, although some atomistic simulation and phenomenological studies have been performed. Such detailed information is needed to construct a model describing the microstructural evolution in fast-neutron irradiated materials that will be of great technological importance for the development of ZrC- based fuel. The goal of the proposed project is to gain fundamental understanding of the radiation-induced defect formation in zirconium carbide and irradiation response (ZrC) by using a combination of state-of-the-art experimental methods and atomistic modeling. This project will combine (1) in situ ion irradiation at a specialized facility at a national laboratory, (2) controlled temperature proton irradiation on bulk samples, and (3) atomistic modeling to gain a fundamental understanding of defect formation in ZrC. The proposed project will cover the irradiation temperatures from cryogenic temperature to as high as 800{degree}C, and dose ranges from 0.1 to 100 dpa. The examination of this wide range of temperatures and doses allows us to obtain an experimental data set that can be effectively used to exercise and benchmark the computer calculations of defect properties. Combining the examination of radiation-induced microstructures mapped spatially and temporally, microstructural evolution during post-irradiation annealing, and atomistic modeling of defect formation and transport energetics will provide new, critical understanding about property changes in ZrC. The behavior of materials under irradiation is determined by the balance between damage production, defect clustering, and lattice response. In order to predict those effects at high temperatures so targeted testing can be expanded and extrapolated beyond the known database, it is necessary to determine the defect energetics and mobilities as these control damage accumulation and annealing. In particular, low-temperature irradiations are invaluable for determining the regions of defect mobility. Computer simulation techniques are particularly useful for identifying basic defect properties, especially if closely coupled with a well-constructed and complete experimental database. The close coupling of calculation and experiment in this project will provide mutual benchmarking and allow us to glean a deeper understanding of the irradiation response of ZrC, which can then be applied to the prediction of its behavior in reactor conditions.

  20. Effects of errors in velocity tilt on maximum longitudinal compression during neutralized drift compression of intense beam pulses: I. general description

    SciTech Connect (OSTI)

    Kaganovich, Igor D.; Massidda, Scottt; Startsev, Edward A.; Davidson, Ronald C.; Vay, Jean-Luc; Friedman, Alex

    2012-06-21

    Neutralized drift compression offers an effective means for particle beam pulse compression and current amplification. In neutralized drift compression, a linear longitudinal velocity tilt (head-to-tail gradient) is applied to the non-relativistic beam pulse, so that the beam pulse compresses as it drifts in the focusing section. The beam current can increase by more than a factor of 100 in the longitudinal direction. We have performed an analytical study of how errors in the velocity tilt acquired by the beam in the induction bunching module limit the maximum longitudinal compression. It is found that the compression ratio is determined by the relative errors in the velocity tilt. That is, one-percent errors may limit the compression to a factor of one hundred. However, a part of the beam pulse where the errors are small may compress to much higher values, which are determined by the initial thermal spread of the beam pulse. It is also shown that sharp jumps in the compressed current density profile can be produced due to overlaying of different parts of the pulse near the focal plane. Examples of slowly varying and rapidly varying errors compared to the beam pulse duration are studied. For beam velocity errors given by a cubic function, the compression ratio can be described analytically. In this limit, a significant portion of the beam pulse is located in the broad wings of the pulse and is poorly compressed. The central part of the compressed pulse is determined by the thermal spread. The scaling law for maximum compression ratio is derived. In addition to a smooth variation in the velocity tilt, fast-changing errors during the pulse may appear in the induction bunching module if the voltage pulse is formed by several pulsed elements. Different parts of the pulse compress nearly simultaneously at the target and the compressed profile may have many peaks. The maximum compression is a function of both thermal spread and the velocity errors. The effects of the finite gap width of the bunching module on compression are analyzed analytically.

  1. FY 2013 Summary Report: Post-Irradiation Examination of Zircaloy...

    Energy Savers [EERE]

    FY13SumRprtPostIrradiationExaminatZircaloy4Samples.pdf More Documents & Publications Neutron Irradiation of Hydrided Cladding Material in HFIR Summary of Initial Activities FY14...

  2. Parametric resonance of a two-dimensional electron gas under bichromatic irradiation Christian Joas

    E-Print Network [OSTI]

    von Oppen, Felix

    Parametric resonance of a two-dimensional electron gas under bichromatic irradiation Christian Joas driving ac fields (bichromatic irradiation). Compared to the case of monochromatic irradiation, which's theorem, gives rise to new qualitative effects specific to bichromatic irradiation. Namely, when

  3. Northern mid-latitude glaciation in the Late Amazonian period of Mars: Criteria for the recognition of debris-covered glacier and valley glacier landsystem deposits

    E-Print Network [OSTI]

    Marchant, David R.

    in talus pile pore space caused lubrication and flow during an earlier climatic regime. A number of factors have remained uncertain, however, including the detailed structure and texture of LDA analogs, to assess the characteristics of LDA/LVF in the northern mid-latitudes of Mars. We find evidence

  4. Omics in the Arctic: Genome-enabled Contributions to Carbon Cycle Research in High-Latitude Ecosystems (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

    ScienceCinema (OSTI)

    Wullschleger, Stan [ORNL

    2013-01-22

    Stan Wullschleger of Oak Ridge National Laboratory on "Omics in the Arctic: Genome-enabled Contributions to Carbon Cycle Research in High-Latitude Ecosystems" on March 22, 2012 at the 7th Annual Genomics of Energy & Environment Meeting in Walnut Creek, California.

  5. New substorm index derived from high-resolution geomagnetic field data at low latitude and its comparison with AE and ASY indices

    E-Print Network [OSTI]

    power near the midnight, multiple ground stations distributing longitudinally are needed measuring Pi2 power. In this study, using data from the longitudinal network of 5 ground stations, we. Pulsations of this type appear clearly in time series from mid- and low-latitude ground stations

  6. Omics in the Arctic: Genome-enabled Contributions to Carbon Cycle Research in High-Latitude Ecosystems (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

    SciTech Connect (OSTI)

    Wullschleger, Stan [ORNL] [ORNL

    2012-03-22

    Stan Wullschleger of Oak Ridge National Laboratory on "Omics in the Arctic: Genome-enabled Contributions to Carbon Cycle Research in High-Latitude Ecosystems" on March 22, 2012 at the 7th Annual Genomics of Energy & Environment Meeting in Walnut Creek, California.

  7. Neogene Low-latitude Seasonal Environmental Variations: Stable Isotopic and Trace Elemental Records in Mollusks from the Florida Platform and the Central American Isthmus 

    E-Print Network [OSTI]

    Tao, Kai

    2012-10-19

    This Ph.D. dissertation integrates stable isotope and trace element geochemistry in modern and fossil gastropod shells to study low-latitude marine paleoenvironments. First, stable isotopes (delta18O and delta13C) and Sr/Ca ratios are used...

  8. The radioactive Substances (Irradiated Material) Exemption Order 1962 

    E-Print Network [OSTI]

    Joseph, Keith

    1962-01-01

    STATUTORY INSTRUMENTS 1962 No. 2647 ATOMIC ENERGY AND RADIOACTIVE SUBSTANCES The Radioactive Substances (Irradiated Material) Exemption Order 1962

  9. APPLICATION OF PHASE-FIELD MODELING TO IRRADIATION EFFECTS IN...

    Office of Scientific and Technical Information (OSTI)

    DEFECTS; FLUCTUATIONS; IRRADIATION; KINETICS; NUCLEATION; RADIATIONS; SIMULATION; THERMODYNAMICS Microstructure evolution; Theory Word Cloud More Like This Full Text Journal...

  10. Response of atmospheric ground level temperatures to changes in the total solar irradiance

    E-Print Network [OSTI]

    Erlykin, Anatoly

    2015-01-01

    The attribution of part of global warming to changes in the total solar irradiance (TSI) is an important topic which is not, yet, fully understood. Here, we examine the TSI induced temperature (T) changes on a variety of time scales, from one day to centuries and beyond, using a variety of assumptions. Also considered is the latitude variation of the T-TSI correlations, where it appears that over most of the globe there is a small increase in the sensitivity of temperature to TSI in time. It is found that the mean global sensitivity (alpha)measured in K(Wm-2)-1 varies from about 0.003 for 1 day, via 0.05 for 11-years to about 0.2 for decades to centuries. We conclude that mean global temperature changes related to TSI are not significant from 1975 onwards. Before 1975, when anthropogenic gases were less important, many of the temperature changes can be attributed to TSI variations. Over much longer periods of time, from Kyear to Myear, the TSI changes are more efficient still, the sensitivity alpha increasing...

  11. Continuous wave laser irradiation of explosives

    SciTech Connect (OSTI)

    McGrane, Shawn D.; Moore, David S.

    2010-12-01

    Quantitative measurements of the levels of continuous wave (CW) laser light that can be safely applied to bare explosives during contact operations were obtained at 532 nm, 785 nm, and 1550 nm wavelengths. A thermal camera was used to record the temperature of explosive pressed pellets and single crystals while they were irradiated using a measured laser power and laser spot size. A visible light image of the sample surface was obtained before and after the laser irradiation. Laser irradiation thresholds were obtained for the onset of any visible change to the explosive sample and for the onset of any visible chemical reaction. Deflagration to detonation transitions were not observed using any of these CW laser wavelengths on single crystals or pressed pellets in the unconfined geometry tested. Except for the photochemistry of DAAF, TATB and PBX 9502, all reactions appeared to be thermal using a 532 nm wavelength laser. For a 1550 nm wavelength laser, no photochemistry was evident, but the laser power thresholds for thermal damage in some of the materials were significantly lower than for the 532 nm laser wavelength. No reactions were observed in any of the studied explosives using the available 300 mW laser at 785 nm wavelength. Tables of laser irradiance damage and reaction thresholds are presented for pressed pellets of PBX9501, PBX9502, Composition B, HMX, TATB, RDX, DAAF, PETN, and TNT and single crystals of RDX, HMX, and PETN for each of the laser wavelengths.

  12. Safety Issues for Hg irradiation Experiment siting -

    E-Print Network [OSTI]

    McDonald, Kirk

    1 SC/RP Safety Issues for Hg irradiation Experiment siting - Activation of air and components water retention Activation of air by 40 pulses of 2E13 p corresponds to approx. 1 yr of operation in EHN1. Lack of beam dump leads to unnecessary activation of components and aggravates air activation #12

  13. Low energy electron irradiation of an apple 

    E-Print Network [OSTI]

    Brescia, Giovanni Batista

    2002-01-01

    simulation. A software package, MCNP (Monte Carlo N-Particle), was used to simulate an electron beam irradiation with a 1.0, 1.5 and 2.0 MeV sources on an apple modeled by interconnecting two spheres. The apple radii were 4.4 cm (perpendicular to its axis...

  14. Irradiation Embritlement in Alloy HT-­9

    SciTech Connect (OSTI)

    Serrano De Caro, Magdalena

    2012-08-27

    HT-9 steel is a candidate structural and cladding material for high temperature lead-bismuth cooled fast reactors. In typical advanced fast reactor designs fuel elements will be irradiated for an extended period of time, reaching up to 5-7 years. Significant displacement damage accumulation in the steel is expected (> 200 dpa) when exposed to dpa-rates of 20-30 dpa{sub Fe}/y and high fast flux (E > 0.1 MeV) {approx}4 x 10{sup 15} n/cm{sup 2}s. Core temperatures could reach 400-560 C, with coolant temperatures at the inlet as low as 250 C, depending on the reactor design. Mechanical behavior in the presence of an intense fast flux and high dose is a concern. In particular, low temperature operation could be limited by irradiation embrittlement. Creep and corrosion effects in liquid metal coolants could set a limit to the upper operating temperature. In this report, we focus on the low temperature operating window limit and describe HT-9 embrittlement experimental findings reported in the literature that could provide supporting information to facilitate the consideration of a Code Case on irradiation effects for this class of steels in fast reactor environments. HT-9 has an extensive database available on irradiation performance, which makes it the best choice as a possible near-term candidate for clad, and ducts in future fast reactors. Still, as it is shown in this report, embrittlement data for very low irradiation temperatures (< 200 C) and very high radiation exposure (> 150 dpa) is scarce. Experimental findings indicate a saturation of DBTT shifts as a function of dose, which could allow for long lifetime cladding operation. However, a strong increase in DBTT shift with decreasing irradiation temperature could compromise operation at low service temperatures. Development of a deep understanding of the physics involved in the radiation damage mechanisms, together with multiscale computer simulation models of irradiation embrittlement will provide the basis to derive trendlines and quantitative engineering predictions.

  15. Irradiation effects in high-density polyethylene Jussi Polvia

    E-Print Network [OSTI]

    Nordlund, Kai

    Irradiation effects in high-density polyethylene Jussi Polvia , Kai Nordlunda a simulations, we have studied the irradiation effects in high density polyethylene. We determined the threshold for the hydrogen atoms in the polyethylene chain. Keywords: molecular dynamics, irradiation, damage threshold

  16. SOLAR IRRADIANCE FORECASTING FOR THE MANAGEMENT OF SOLAR ENERGY SYSTEMS

    E-Print Network [OSTI]

    Heinemann, Detlev

    SOLAR IRRADIANCE FORECASTING FOR THE MANAGEMENT OF SOLAR ENERGY SYSTEMS Detlev Heinemann Oldenburg in irradiance forecasting have been presented more than twenty years ago (Jensenius and Cotton, 1981), when or progress with respect to the development of solar irradiance forecasting methods. Heck and Takle (1987

  17. Influence of surface waves on measured and modeled irradiance profiles

    E-Print Network [OSTI]

    Boss, Emmanuel S.

    Influence of surface waves on measured and modeled irradiance profiles J. Ronald V. Zaneveld-parallel assumption. We show that the Gershun equation is valid if the irradiance is averaged over a sufficiently in which horizontal gradients of irradiance in the presence of waves are much larger than vertical

  18. On the relationship between radiance and irradiance: determining

    E-Print Network [OSTI]

    O'Brien, James F.

    On the relationship between radiance and irradiance: determining the illumination from images between incoming radiance and irradiance. Specifically, we address the question of whether it is possible. This is a fundamental question in computer vision and inverse radiative transfer. We show that the irradiance can

  19. SPECTRAL SOLAR IRRADIANCE AND ITS ENTROPIC EFFECT ON EARTH'S CLIMATE

    E-Print Network [OSTI]

    SPECTRAL SOLAR IRRADIANCE AND ITS ENTROPIC EFFECT ON EARTH'S CLIMATE Wei Wu1 , Yangang Liu1 of the spectral solar irradiance (SSI) at the top of the Earth's atmosphere by the Solar Radiation and Climate the total solar irradiance (TSI) at the top of the Earth's atmosphere (TOA) varies little (only about 0

  20. MATERIAL IRRADIATION DAMAGE STUDIES FOR HIGH POWER ACCELERATORS*

    E-Print Network [OSTI]

    McDonald, Kirk

    MATERIAL IRRADIATION DAMAGE STUDIES FOR HIGH POWER ACCELERATORS* N. Simos# , H. Kirk, L. Trung, H under severe shock and high irradiation exposure. The limitations of solid materials to function as high performance targets and in particular the effects of irradiation on key material properties are assessed

  1. ATMOSPHERIC TURBIDITY DETERMINATION FROM IRRADIANCE RATIOS Chris Gueymard Frank Vignola

    E-Print Network [OSTI]

    Oregon, University of

    ATMOSPHERIC TURBIDITY DETERMINATION FROM IRRADIANCE RATIOS Chris Gueymard Frank Vignola Florida irradiance measurements and other atmo- spheric parameters. An error analysis and various tests against cloudless and the diffuse irradiance data are very accurate. Yet, this method is insensitive to errors

  2. A model for the diffuse attenuation coefficient of downwelling irradiance

    E-Print Network [OSTI]

    Lee, Zhongping

    A model for the diffuse attenuation coefficient of downwelling irradiance Zhong-Ping Lee1 Naval] The diffuse attenuation coefficient for downwelling irradiance (Kd) is an important parameter for ocean of downwelling irradiance, J. Geophys. Res., 110, C02016, doi:10.1029/2004JC002275. 1. Introduction [2] Diffuse

  3. UV Irradiation and Humic Acid Mediate Aggregation of Aqueous

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    UV Irradiation and Humic Acid Mediate Aggregation of Aqueous Fullerene (nC60) Nanoparticles X I A O by UV irradiation remarkablyincreasednC60 stabilityduetotheincreasednegative surface charge and reduced hindrance effect, it had little influence on the stability of UV-irradiated nC60 in NaCl due to reduced

  4. Vertex-Based Formulations of Irradiance from Polygonal Sources

    E-Print Network [OSTI]

    Vertex-Based Formulations of Irradiance from Polygonal Sources Michael M. Stark UUCS-00-012 School of Computing University of Utah Salt Lake City, UT 84112 USA May 29, 2000 Abstract Irradiance at a point-Based Formulations of Irradiance from Polygonal Sources Technical Report UUCS-00-012 Michael M. Stark Department

  5. Proton Irradiation Damage Assessment of Carbon Reinforced Composites

    E-Print Network [OSTI]

    McDonald, Kirk

    Proton Irradiation Damage Assessment of Carbon Reinforced Composites: 2-D & 3-D Weaved Structures. of thermal expansion (CTE). #12;Positive news regarding 3D Carbon composite kept coming !! Irradiation damage-carbon under heavy irradiation (LHC Phase-I collimator material) Phase 2 Expose 2D & 3D carbon

  6. Reflected and Transmitted Irradiance from Area Sources using Vertex Tracing

    E-Print Network [OSTI]

    Utah, University of

    Reflected and Transmitted Irradiance from Area Sources using Vertex Tracing Michael M. Stark irradiance analytically from polygonal luminaires in polygonal environments has proven effective for direct- ally used edge-based solutions to the irradiance integral; our previous work pre- sented a vertex

  7. Ion irradiation effects in natural garnets: Comparison with zircon

    E-Print Network [OSTI]

    Utsunomiya, Satoshi

    Ion irradiation effects in natural garnets: Comparison with zircon S. Utsunomiya, L.M. Wang, R ; Z ¼ 8) under ion-beam irradiation was investigated in order to compare its radiation susceptibility transmission electron microscopy during irradiation with 1.0 MeV Kr2þ over the temperature range of 50­1070 K

  8. K.K. Gan 1 Summary of Irradiation Activity

    E-Print Network [OSTI]

    Gan, K. K.

    K.K. Gan 1 Summary of Irradiation Activity September 22, 2010 K.K. Gan The Ohio State University with 300 MeV pions in August VCSEL/PIN Irradiation #12;K.K. Gan TWEPP2010 3 array VCSEL driver Chips Irradiation #12;K.K. Gan TWEPP2010 4 Infinicor SX+: participating institution: SMU

  9. 2nd High-Power Targetry Workshop MATERIAL IRRADIATION STUDIES

    E-Print Network [OSTI]

    McDonald, Kirk

    2nd High-Power Targetry Workshop MATERIAL IRRADIATION STUDIES FOR HIGH-INTENSITY PROTON BEAM/fracture strength · resilience to irradiation damage · Other than that, we are not asking for much!!!! And another based on non-irradiated material properties may show that it is possible to achieve 2 or even 4 MW

  10. Sensitivity of ultrasonic nonlinearity to irradiated, annealed, and re-irradiated microstructure changes in RPV steels

    SciTech Connect (OSTI)

    Matlack, Katie; Kim, J-Y.; Wall, J.J.; Jacobs, L.J.; Sokolov, Mikhail A

    2014-05-01

    The planned life extension of nuclear reactors throughout the US and abroad will cause reactor vessel and internals materials to be exposed to more neutron irradiation than was originally intended. A nondestructive evaluation (NDE) method to monitor radiation damage would enable safe and cost-effective continued operation of nuclear reactors. Radiation damage in reactor pressure vessel (RPV) steels causes microstructural changes that leave the material in an embrittled state. Nonlinear ultrasound is an NDE technique quantified by the measurable acoustic nonlinearity parameter, which is sensitive to microstructural changes in metallic materials such as dislocations, precipitates and their combinations. Recent research has demonstrated the sensitivity of the acoustic nonlinearity parameter to increasing neutron fluence in representative RPV steels. The current work considers nonlinear ultrasonic experiments conducted on similar RPV steel samples that had a combination of irradiation, annealing, re-irradiation, and/or re-annealing to a total neutron fluence of 0.5 5 1019 n/cm2 (E > 1 MeV) at an irradiation temperature of 290 C. The acoustic nonlinearity parameter generally increased with increasing neutron fluence, and consistently decreased from the irradiated to the annealed state over different levels of neutron fluence. Results of the measured acoustic nonlinearity parameter are compared with those from previous measurements on other RPV steel samples. This comprehensive set of results illustrates the dependence of the measured acoustic nonlinearity parameter on neutron fluence, material composition, irradiation temperature and annealing.

  11. Testing three 90Whr Dell Batteries for Latitude E6410 I have been able, for complicated reasons, to test three batteries sold as 9cell 90Whr batteries for

    E-Print Network [OSTI]

    Sloman, Aaron

    Testing three 90Whr Dell Batteries for Latitude E6410 I have been able, for complicated reasons, to test three batteries sold as 9cell 90Whr batteries for the Dell Latitude E6410 computer, one made battery was fully charged then allowed to discharge while the laptop was on, and not doing very much

  12. LOW-LATITUDE CORONAL HOLES AT THE MINIMUM OF THE 23rd SOLAR CYCLE This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    of the harmonic power spectrum of the solar magnetic field demonstrates a greater prevalence of multiLOW-LATITUDE CORONAL HOLES AT THE MINIMUM OF THE 23rd SOLAR CYCLE This article has been downloaded reserved. Printed in the U.S.A. LOW-LATITUDE CORONAL HOLES AT THE MINIMUM OF THE 23rd SOLAR CYCLE Valentyna

  13. Climatology of Mid-latitude Ionospheric Disturbances from the Very Large Array Low-frequency Sky Survey

    E-Print Network [OSTI]

    Helmboldt, J F; Cotton, W D

    2012-01-01

    The results of a climatological study of ionospheric disturbances derived from observations of cosmic sources from the Very Large Array (VLA) Low-frequency Sky Survey (VLSS) are presented. We have used the ionospheric corrections applied to the 74 MHz interferometric data within the VLSS imaging process to obtain fluctuation spectra for the total electron content (TEC) gradient on spatial scales from a few to hundreds of kilometers and temporal scales from less than one minute to nearly an hour. The observations sample nearly all times of day and all seasons. They also span latitudes and longitudes from 28 deg. N to 40 deg. N and 95 deg. W to 114 deg. W, respectively. We have binned and averaged the fluctuation spectra according to time of day, season, and geomagnetic (Kp index) and solar (F10.7) activity. These spectra provide a detailed, multi-scale account of seasonal and intraday variations in ionospheric activity with wavelike structures detected at wavelengths between about 35 and 250 km. In some cases,...

  14. Physical and Mathematical Properties of a Quasi-Geostrophic Model of Intermediate Complexity of the Mid-Latitudes Atmospheric Circulation

    E-Print Network [OSTI]

    Valerio Lucarini; Antonio Speranza; Renato VItolo

    2005-11-24

    A quasi-geostrophic intermediate complexity model is considered, providing a schematic representation of the baroclinic conversion processes which characterize the physics of the mid-latitudes atmospheric circulation. The model is relaxed towards a given latitudinal temperature profile, which acts as baroclinic forcing, controlled by a parameter TE determining the forced equator-to-pole temperature gradient. As TE increases, a transition takes place from a stationary regime to a periodic regime, and eventually to an earth-like chaotic regime where evolution takes place on a strange attractor. The dependence of the attractor dimension, metric entropy, and bounding box volume in phase space is studied by varying both TE and model resolution. The statistical properties of observables having physical relevance, namely the total energy of the system and the latitudinally averaged zonal wind, are also examined. It is emphasized that while the attractor's properties are quite sensitive to model resolution, the global physical observables depend less critically on it. For more detailed physical observables, such as the latitudinal profiles of the zonal wind, model resolution again may be critical: the effectiveness of the zonal wind convergence, acting as barotropic stabilization of the baroclinic waves, heavily relies on the details of the latitudinal structure of the fields. The necessity and complementarity of both the dynamical systems and physical approach is underlined.

  15. Reconciliation of local and long-range tilt correlations in underdoped La2-xBaxCuO4(0 ? x ? 0.155)

    SciTech Connect (OSTI)

    Bozin, Emil S.; Zhong, Ruidan; Knox, Kevin R.; Gu, Genda; Hill, John P.; Tranquada, John M.; Billinge, Simon J. L.

    2015-02-26

    A long standing puzzle regarding the disparity of local and long range CuO? octahedral tilt correlations in the underdoped regime of La??xBaxCuO? is addressed by utilizing complementary neutron powder diffraction and inelastic neutron scattering (INS) approaches. Long-range and static CuO? tilt order with orthogonally inequivalent Cu-O bonds in the CuO? planes in the low temperature tetragonal (LTT) phase is succeeded on warming through the low-temperature transition by one with orthogonally equivalent bonds in the low temperature orthorhombic (LTO) phase. In contrast, the signatures of LTT-type tilts in the instantaneous local atomic structure persist on heating throughout the LTO crystallographic phase on the nanoscale, although becoming weaker as temperature increases. Analysis of the INS spectra for the x = 1/8 composition reveals the dynamic nature of the LTT-like tilt fluctuations within the LTO phase and their 3D character. The doping dependence of relevant structural parameters indicates that the magnitude of the Cu-O bond anisotropy has a maximum at x = 1/8 doping where bulk superconductivity is most strongly suppressed, suggesting that the structural anisotropy might be influenced by electron-phonon coupling and the particular stability of the stripe-ordered phase at this composition. The bond-length modulation that pins stripe order is found to be remarkably subtle, with no anomalous bond length disorder at low temperature, placing an upper limit on any in-plane Cu-O bondlength anisotropy. The results further reveal that although appreciable octahedral tilts persist through the high-temperature transition and into the high temperature tetragonal (HTT) phase, there is no significant preference between different tilt directions in the HTT regime. As a result, this study also exemplifies the importance of a systematic approach using complementary techniques when investigating systems exhibiting a large degree of complexity and subtle structural responses.

  16. Forward and reverse characteristics of irradiated MOSFETs

    SciTech Connect (OSTI)

    Paccagnella, A.; Ceschia, M.; Verzellesi, G.; Dalla Betta, G.F.; Soncini, G.; Bellutti, P.; Fuochi, P.G.

    1996-06-01

    pMOSFETs biased with V{sub gs} < V{sub gd} during Co{sup 60} {gamma} irradiation have shown substantial differences between the forward and reverse subthreshold characteristics, induced by a non-uniform charge distribution in the gate oxide. Correspondingly, modest differences have been observed in the over-threshold I-V characteristics. After irradiation, the forward subthreshold curves can shift at higher or lower gate voltages than the reverse ones. The former behavior has been observed in long-channel devices, in agreement with the classical MOS theory and numerical simulations. The latter result has been obtained in short-channel devices, and it has been correlated to a parasitic punch-through conduction mechanism.

  17. Nanodot formation induced by femtosecond laser irradiation

    SciTech Connect (OSTI)

    Abere, M. J.; Kang, M.; Goldman, R. S.; Yalisove, S. M. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States); Chen, C. [Applied Physics Program, University of Michigan, Ann Arbor, Michigan 48109 (United States); Rittman, D. R. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); Phillips, J. D. [Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109 (United States); Torralva, B. [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2014-10-20

    The femtosecond laser generation of ZnSe nanoscale features on ZnSe surfaces was studied. Irradiation with multiple exposures produces 10–100?nm agglomerations of nanocrystalline ZnSe while retaining the original single crystal structure of the underlying material. The structure of these nanodots was verified using a combination of scanning transmission electron microscopy, scanning electron microscopy, and atomic force microscopy. The nanodots continue to grow hours after irradiation through a combination of bulk and surface diffusion. We suggest that in nanodot formation the result of ultrafast laser induced point defect formation is more than an order of magnitude below the ZnSe ultrafast melt threshold fluence. This unique mechanism of point defect injection will be discussed.

  18. Irradiated closed Friedmann brane-worlds

    E-Print Network [OSTI]

    Zoltán Keresztes; Ibolya Képíró

    2006-10-10

    We consider the evolution of a closed Friedmann brane irradiated by a bulk black hole. Both absorption on the brane and transmission across the brane are allowed, the latter representing a generalization over a previously studied model. Without transmission, a critical behaviour could be observed, when the acceleration due to radiation pressure and the deceleration introduced by the increasing self-gravity of the brane roughly compensate each other. We show here that increasing transmission leads to the disappearance of the critical behaviour.

  19. ARM - Measurement - Shortwave narrowband direct downwelling irradiance

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska Outreach Homepolarization ARM Datadownwelling irradiance

  20. ARM - Measurement - Shortwave narrowband total downwelling irradiance

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska Outreach Homepolarization ARM Datadownwellingdownwelling irradiance

  1. Upgrade to the Birmingham Irradiation Facility

    E-Print Network [OSTI]

    Dervan, P; Hodgson, P; Marin- Reyes; Parker, K; Wilson, J; Baca, M

    2015-01-01

    The Birmingham Irradiation Facility was developed in 2013 at the University of Birmingham using the Medical Physics MC40 cyclotron. It can achieve High Luminosity LHC (HL-LHC) fluences of 10^15 (1 MeV neutron equivalent (neq)) cm^-2 in 80 s with proton beam currents of 1 ?A and so can evaluate effectively the performance and durability of detector technologies and new components to be used for the HL-LHC. Irradiations of silicon sensors and passive materials can be carried out in a temperature controlled cold box which moves continuously through the homogenous beamspot. This movement is provided by a pre-configured XY-axis Cartesian robot scanning system. In 2014 the cooling system and cold box were upgraded from a recirculating glycol chiller system to a liquid nitrogen evaporative system. The new cooling system achieves a stable temperature of 50 1C in 30 min and aims to maintain sub-0 1C temperatures on the sensors during irradiations. This paper reviews the design, development, commissioning and perform...

  2. Irradiation Environment of the Materials Test Station

    SciTech Connect (OSTI)

    Pitcher, Eric John

    2012-06-21

    Conceptual design of the proposed Materials Test Station (MTS) at the Los Alamos Neutron Science Center (LANSCE) is now complete. The principal mission is the irradiation testing of advanced fuels and materials for fast-spectrum nuclear reactor applications. The neutron spectrum in the fuel irradiation region of MTS is sufficiently close to that of fast reactor that MTS can match the fast reactor fuel centerline temperature and temperature profile across a fuel pellet. This is an important characteristic since temperature and temperature gradients drive many phenomena related to fuel performance, such as phase stability, stoichiometry, and fission product transport. The MTS irradiation environment is also suitable in many respects for fusion materials testing. In particular, the rate of helium production relative to atomic displacements at the peak flux position in MTS matches well that of fusion reactor first wall. Nuclear transmutation of the elemental composition of the fusion alloy EUROFER97 in MTS is similar to that expected in the first wall of a fusion reactor.

  3. Irradiation response and stability of nanoporous materials

    SciTech Connect (OSTI)

    Fu, Engang [Los Alamos National Laboratory; Wang, Yongqiang [Los Alamos National Laboratory; Serrano De Caro, Magdalena [Los Alamos National Laboratory; Caro, Jose A. [Los Alamos National Laboratory; Zepeda-Ruiz, L [Lawrence Livermore national Laboratory; Bringa, E. [CONICET, Universidad de Cuyo, Argentina; Nastasi, Mike [University of Nebraska, Lincoln, NE; Baldwin, Jon K. [Los Alamos National Laboratory

    2012-08-28

    Nanoporous materials consist of a regular organic or inorganic framework supporting a regular, porous structure. Pores are by definition roughly in the nanometre range, that is between 0.2 nm and 100 nm. Nanoporous materials can be subdivided into 3 categories (IUPAC): (1) Microporous materials - 0.2-2 nm; (2) Mesoporous materials - 2-50 nm; and (3) Macroporous materials - 50-1000 nm. np-Au foams were successfully synthesized by de-alloying process. np-Au foams remain porous structure after Ne ion irradiation to 1 dpa. Stacking Fault Tetrahedra (SFTs) were observed in RT irradiated np-Au foams under the highest and intermediate fluxes, but not under the lowest flux. SFTs were not observed in LNT irradiated np-Au foams under all fluxes. The vacancy diffusivity in Au at RT is high enough so that the vacancies have enough time to agglomerate and then collapse to form SFTs. The high ion flux creates more damage per unit time; vacancies don't have enough time to diffuse or recombine. As a result, SFTs were formed at high ion fluxes.

  4. EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS

    SciTech Connect (OSTI)

    Clark, E.

    2011-09-22

    Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Polymeric materials become damaged by exposure over time to ionizing radiation. Despite the limited lifetime, polymers have unique engineering material properties and polymers continue to be used in tritium handling systems. In tritium handling systems, polymers are employed mainly in joining applications such as valve sealing surfaces (eg. Stem tips, valve packing, and O-rings). Because of the continued need to employ polymers in tritium systems, over the past several years, programs at the Savannah River National Laboratory have been studying the effect of tritium on various polymers of interest. In these studies, samples of materials of interest to the SRS Tritium Facilities (ultra-high molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, Teflon{reg_sign}), Vespel{reg_sign} polyimide, and the elastomer ethylene propylene diene monomer (EPDM)) have been exposed in closed containers to tritium gas initially at 1 atmosphere pressure. These studies have demonstrated the degradation of properties when exposed to tritium gas. Also, the radiolytic production of significant amounts of hydrogen has been observed for UHMW-PE and EPDM. The study documented in this report exposes two similar formulations of EPDM elastomer to gamma irradiation in a closed container backfilled with deuterium. Deuterium is chemically identical to protium and tritium, but allows the identification of protium that is radiolytically produced from the samples. The goal of this program is to compare and contrast the response of EPDM exposure to two different types of ionizing radiation in a similar chemical environment.

  5. The spectral irradiance traceability chain at PTB

    SciTech Connect (OSTI)

    Sperfeld, P.; Pape, S.; Nevas, S.

    2013-05-10

    Spectral irradiance is a fundamental radiometric unit. Its application to measurement results requires qualified traceability to basic units of the international system of units (Systeme international d'unites, SI). The Physikalisch-Technische Bundesanstalt (PTB) is amongst other national metrological institutes (NMIs) responsible for the realization, maintenance and dissemination of various radiometric and photometric units based on and traceable to national standards. The unit of spectral irradiance is realized and represented by a blackbody-radiator as the national primary standard of the PTB. Based on Planck's radiation law, the irradiance is calculated and realized for any wavelength taking into account the exact knowledge of the radiation temperature and the geometrical parameters. Using a double-monochromator-based spectroradiometer system, secondary standard lamps can be calibrated by direct comparison to the blackbody-radiator (substitution method). These secondary standard lamps are then used at the PTB to calibrate standard lamps of customers. The customers themselves use these so-called transfer standards to calibrate their working standard lamps. These working standards are then used to calibrate own spectroradiometers or sources. This rather complex calibration chain is a common procedural method that for the customers generally leads to satisfying measurement results on site. Nevertheless, the standard lamps in use have to fulfill highest requirements concerning stability and reproducibility. Only this allows achieving comparably low transfer measurement uncertainties, which occur at each calibration step. Thus, the PTB is constantly investigating the improvement and further development of transfer standards and measurement methods for various spectral regions. The realization and dissemination of the spectral irradiance using the blackbody-radiator at the PTB is accomplished with worldwide approved minimized measurement uncertainties confirmed by international intercomparisons among NMIs. Ultimately, the spectral irradiance can be realized with expanded measurement uncertainties of far less than 1 % over a wide spectral range. Thus, for customers with high demands on low measurement uncertainties, it is possible to calibrate their working standards directly against the blackbody-radiator, taking into account the higher necessary effort. In special cases it is possible to calibrate the customer's spectroradiometric facilities directly in front of the blackbody-radiator. In the context of the European Metrology Research Project Traceability for surface spectral solar ultraviolet radiation, the traceability chain will be improved and adapted.

  6. Evaluation of Neutron Irradiated Silicon Carbide and Silicon Carbide Composites

    SciTech Connect (OSTI)

    Newsome G, Snead L, Hinoki T, Katoh Y, Peters D

    2007-03-26

    The effects of fast neutron irradiation on SiC and SiC composites have been studied. The materials used were chemical vapor deposition (CVD) SiC and SiC/SiC composites reinforced with either Hi-Nicalon{trademark} Type-S, Hi-Nicalon{trademark} or Sylramic{trademark} fibers fabricated by chemical vapor infiltration. Statistically significant numbers of flexural samples were irradiated up to 4.6 x 10{sup 25} n/m{sup 2} (E>0.1 MeV) at 300, 500 and 800 C in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Dimensions and weights of the flexural bars were measured before and after the neutron irradiation. Mechanical properties were evaluated by four point flexural testing. Volume increase was seen for all bend bars following neutron irradiation. Magnitude of swelling depended on irradiation temperature and material, while it was nearly independent of irradiation fluence over the fluence range studied. Flexural strength of CVD SiC increased following irradiation depending on irradiation temperature. Over the temperature range studied, no significant degradation in mechanical properties was seen for composites fabricated with Hi-Nicalon{trademark} Type-S, while composites reinforced with Hi-Nicalon{trademark} or Sylramic fibers showed significant degradation. The effects of irradiation on the Weibull failure statistics are also presented suggesting a reduction in the Weibull modulus upon irradiation. The cause of this potential reduction is not known.

  7. Irradiation effect on deuterium behaviour in low-dose HFIR neutron-irradiated tungsten

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

    Shimada, Masashi; Cao, G.; Otsuka, T.; Hara, M.; Kobayashi, M.; Oya, Y.; Hatano, Y.

    2014-12-01

    Tungsten samples were irradiated by neutrons in the High Flux Isotope Reactor, Oak Ridge National Laboratory at reactor coolant temperatures of 50-70°C to low displacement damage of 0.025 and 0.3 dpa under the framework of the US-Japan TITAN program (2007-2013). After cooling down, the HFIR neutron-irradiated tungsten samples were exposed to deuterium plasmas in the Tritium Plasma Experiment, Idaho National Laboratory at 100, 200 and 500 °C twice at the ion fluence of 5×10²? m?² to reach a total ion fluence of 1×10²? m?² in order to investigate the near surface deuterium retention and saturation via nuclear reaction analysis. Finalmore »thermal desorption spectroscopy was performed to elucidate irradiation effect on total deuterium retention. Nuclear reaction analysis results showed that the maximum near surface (« less

  8. Major shifts in calcareous phytoplankton assemblages through the Eocene-Oligocene transition of Tanzania and their implications for low-latitude primary production 

    E-Print Network [OSTI]

    Jones, Tom Dunkley; Bown, Paul R.; Pearson, Paul N.; Wade, Bridget S.; Coxall, Helen K.; Lear, Caroline H.

    2008-01-01

    phytoplankton assemblages through the Eocene-Oligocene transition of Tanzania and their implications for low-latitude primary production Tom Dunkley Jones, 1 Paul R. Bown, 2 Paul N. Pearson, 3 Bridget S. Wade, 4 Helen K. Coxall, 3 and Caroline H. Lear 3 Received... 28 April 2008; revised 30 June 2008; accepted 18 July 2008; published 22 October 2008. [1] A high-resolution record of exceptionally well preserved calcareous nannofossil assemblages from Tanzania is marked by two key transitions closely related...

  9. Observational evidence for a changing tilt of the accretion disk with respect to the orbital plane in Her X-1 over its 35 day cycle

    E-Print Network [OSTI]

    D. Klochkov; N. Shakura; K. Postnov; R. Staubert; J. Wilms; N. Ketsaris

    2007-11-12

    Analysis and interpretation of the Her X-1 X-ray light curve obtained with the ASM onbord RXTE over the period 1996 February to 2004 September is presented. We report that the features found previously in the averaged X-ray lightcurve are confirmed by the new RXTE/ASM data. In particular, anomalous dips and post-eclipse recoveries in two successive orbits in the short-on state are found to be prominent and stable details of the light curve. We argue that a change of the tilt of the accretion disk over the 35-day period is necessary to account for these features and show that our numerical model can explain such a behavior of the disk and reproduce the observed details of the light curve.

  10. Graphitization of polymer surfaces by scanning ion irradiation

    SciTech Connect (OSTI)

    Koval, Yuri [Department of Physics, Universität Erlangen-Nürnberg, Erwin-Rommel-Str. 1, 91058 Erlangen (Germany)

    2014-10-20

    Graphitization of polymer surfaces was performed by low-energy Ar{sup +} and He{sup +} ion irradiation. A method of scanning irradiation was implemented. It was found that by scanning ion irradiation, a significantly higher electrical conductivity in the graphitized layers can be achieved in comparison with a conventional broad-beam irradiation. The enhancement of the conductance becomes more pronounced for narrower and better collimated ion beams. In order to analyze these results in more detail, the temperature dependence of conductance of the irradiated samples was investigated. The results of measurements are discussed in terms of weak localization corrections to conductance in disordered metals. The observed effects can be explained by enlargement of graphitic patches, which was achieved with the scanning ion irradiation method.

  11. Emulation of reactor irradiation damage using ion beams

    SciTech Connect (OSTI)

    Was, G. S.; Jiao, Z.; Getto, E.; Sun, K.; Monterrosa, A. M.; Maloy, S. A.; Anderoglu, O.; Sencer, B. H.; Hackett, M.

    2014-06-14

    The continued operation of existing light water nuclear reactors and the development of advanced nuclear reactor depend heavily on understanding how damage by radiation to levels degrades materials that serve as the structural components in reactor cores. The first high dose ion irradiation experiments on a ferritic-martensitic steel showing that ion irradiation closely emulates the full radiation damage microstructure created in-reactor are described. Ferritic-martensitic alloy HT9 (heat 84425) in the form of a hexagonal fuel bundle duct (ACO-3) accumulated 155 dpa at an average temperature of 443°C in the Fast Flux Test Facility (FFTF). Using invariance theory as a guide, irradiation of the same heat was conducted using self-ions (Fe++) at 5 MeV at a temperature of 460°C and to a dose of 188 displacements per atom. The void swelling was nearly identical between the two irradiation and the size and density of precipitates and loops following ion irradiation are within a factor of two of those for neutron irradiation. The level of agreement across all of the principal microstructure changes between ion and reactor irradiation establishes the capability of tailoring ion irradiation to emulate the reactor-irradiated microstructure.

  12. Emulation of reactor irradiation damage using ion beams

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

    Was, G. S.; Jiao, Z.; Getto, E.; Sun, K.; Monterrosa, A. M.; Maloy, S. A.; Anderoglu, O.; Sencer, B. H.; Hackett, M.

    2014-06-14

    The continued operation of existing light water nuclear reactors and the development of advanced nuclear reactor depend heavily on understanding how damage by radiation to levels degrades materials that serve as the structural components in reactor cores. The first high dose ion irradiation experiments on a ferritic-martensitic steel showing that ion irradiation closely emulates the full radiation damage microstructure created in-reactor are described. Ferritic-martensitic alloy HT9 (heat 84425) in the form of a hexagonal fuel bundle duct (ACO-3) accumulated 155 dpa at an average temperature of 443°C in the Fast Flux Test Facility (FFTF). Using invariance theory as a guide,more »irradiation of the same heat was conducted using self-ions (Fe++) at 5 MeV at a temperature of 460°C and to a dose of 188 displacements per atom. The void swelling was nearly identical between the two irradiation and the size and density of precipitates and loops following ion irradiation are within a factor of two of those for neutron irradiation. The level of agreement across all of the principal microstructure changes between ion and reactor irradiation establishes the capability of tailoring ion irradiation to emulate the reactor-irradiated microstructure.« less

  13. Irradiation Effects on Human Cortical Bone Fracture Behavior

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

    on different size scales within bone, as well as the role of sustained irradiation damage. Combining in situ mechanical testing with synchrotron x-ray diffraction imaging and...

  14. Irradiation Effects on Human Cortical Bone Fracture Behavior

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

    Irradiation Effects on Human Cortical Bone Fracture Behavior Print Human bone is strong but still fallible. To better predict fracturing in bone, researchers need a mechanistic...

  15. Emulation of reactor irradiation damage using ion beams

    SciTech Connect (OSTI)

    G. S. Was; Z. Jiao; E. Beckett; A. M. Monterrosa; O. Anderoglu; B. H. Sencer; M. Hackett

    2014-10-01

    The continued operation of existing light water nuclear reactors and the development of advanced nuclear reactor depend heavily on understanding how damage by radiation to levels degrades materials that serve as the structural components in reactor cores. The first high dose ion irradiation experiments on a ferritic-martensitic steel showing that ion irradiation closely emulates the full radiation damage microstructure created in-reactor are described. Ferritic-martensitic alloy HT9 (heat 84425) in the form of a hexagonal fuel bundle duct (ACO-3) accumulated 155 dpa at an average temperature of 443°C in the Fast Flux Test Facility (FFTF). Using invariance theory as a guide, irradiation of the same heat was conducted using self-ions (Fe++) at 5 MeV at a temperature of 460°C and to a dose of 188 displacements per atom. The void swelling was nearly identical between the two irradiations and the size and density of precipitates and loops following ion irradiation are within a factor of two of those for neutron irradiation. The level of agreement across all of the principal microstructure changes between ion and reactor irradiations establishes the capability of tailoring ion irradiations to emulate the reactor-irradiated microstructure.

  16. Molecular weight distributions of irradiated siloxane-based elastomers...

    Office of Scientific and Technical Information (OSTI)

    to predict trends for the evolution of the distribution of MWBC of polymers under irradiation. The approach described herein can also discern heterogeneities in radiation...

  17. A New Solar Irradiance Reference Spectrum

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach HomeA Better Anode Design to Improve Lithium-Ion Batteries PrintA New Solar Irradiance Reference Spectrum

  18. ARM - Measurement - Shortwave narrowband diffuse downwelling irradiance

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska Outreach Homepolarization ARM Datadownwelling irradiance ARM Data

  19. ARM - Measurement - Shortwave narrowband diffuse upwelling irradiance

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska Outreach Homepolarization ARM Datadownwelling irradiance ARM

  20. ARM - Measurement - Shortwave spectral total downwelling irradiance

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska Outreach Homepolarization ARMtotal downwelling irradiance ARM Data

  1. BNL Irradiation and Characterization Studies Summary Report on HP Accelerator Material Research

    E-Print Network [OSTI]

    McDonald, Kirk

    BNL Irradiation and Characterization Studies Summary Report on HP Accelerator Material Research Reporting on (ONLY): · Irradiation and micro- macro-characterization of Beryllium · Irradiation Damage and Assessment of Graphite · Irradiation and Characterization of Ti-alloys (Ti6Al4V and Gum Metal) · Irradiation

  2. Irradiation-induced effects of proton irradiation on zirconium carbides with different stoichiometries

    SciTech Connect (OSTI)

    Y. Huang; B.R. Maier; T.R. Allen

    2014-10-01

    Zirconium carbide (ZrC) is being considered for utilization in deep burn TRISO fuel particles for hightemperature, gas-cooled reactors. Zirconium carbide has a cubic B1 type crystal structure along with a very high melting point (3420 ?C), exceptional hardness and good thermal and electrical conductivities. Understanding the ZrC irradiation response is crucial for establishing ZrC as an alternative component in TRISO fuel. Until now, very few studies on irradiation effects on ZrC have been released and fundamental aspects of defect evolution and kinetics are not well understood although some atomistic simulations and phenomenological studies have been performed. This work was carried out to understand the damage evolution in float-zone refined ZrC with different stoichiometries. Proton irradiations at 800 ?C up to doses of 3 dpa were performed on ZrCx (where x ranges from 0.9 to 1.2) to investigate the damage evolution. The irradiation-induced defects, such as density of dislocation loops, at different stoichiometries and doses which were characterized by transmission electron microscopy (TEM) is presented and discussed.

  3. On the effect of x-ray irradiation on the deformation and fracture behavior of human cortical bone

    E-Print Network [OSTI]

    Barth, Holly D.

    2010-01-01

    effects  of  gamma  irradiation  on  allograft  biology S.   Effects  of  gamma? irradiation  on  the  human bone  after  gamma  irradiation.   J.   Bone  Joint  Surg. ?

  4. Irradiation Programs and Test Plans to Assess High-Fluence Irradiation Assisted Stress Corrosion Cracking Susceptibility.

    SciTech Connect (OSTI)

    Teysseyre, Sebastien

    2015-03-01

    . Irradiation assisted stress corrosion cracking (IASCC) is a known issue in current reactors. In a 60 year lifetime, reactor core internals may experience fluence levels up to 15 dpa for boiling water reactors (BWR) and 100+ dpa for pressurized water reactors (PWR). To support a safe operation of our fleet of reactors and maintain their economic viability it is important to be able to predict any evolution of material behaviors as reactors age and therefore fluence accumulated by reactor core component increases. For PWR reactors, the difficulty to predict high fluence behavior comes from the fact that there is not a consensus of the mechanism of IASCC and that little data is available. It is however possible to use the current state of knowledge on the evolution of irradiated microstructure and on the processes that influences IASCC to emit hypotheses. This report identifies several potential changes in microstructure and proposes to identify their potential impact of IASCC. The susceptibility of a component to high fluence IASCC is considered to not only depends on the intrinsic IASCC susceptibility of the component due to radiation effects on the material but to also be related to the evolution of the loading history of the material and interaction with the environment as total fluence increases. Single variation type experiments are proposed to be performed with materials that are representative of PWR condition and with materials irradiated in other conditions. To address the lack of IASCC propagation and initiation data generated with material irradiated in PWR condition, it is proposed to investigate the effect of spectrum and flux rate on the evolution of microstructure. A long term irradiation, aimed to generate a well-controlled irradiation history on a set on selected materials is also proposed for consideration. For BWR, the study of available data permitted to identify an area of concern for long term performance of component. The efficiency of hydrogen water chemistry mitigation technology may decrease as fluence increases for high-stress intensity factors. This report describes a program plan to determine the efficiency of hydrogen water chemistry as a function of the stress intensity factor applied and fluence. The use of existing, available, materials and the generation of additional materials via irradiation in a research reactor are considered.

  5. Optimisation of buildings' solar irradiation availability

    SciTech Connect (OSTI)

    Kaempf, Jerome Henri; Montavon, Marylene; Bunyesc, Josep; Robinson, Darren; Bolliger, Raffaele

    2010-04-15

    In order to improve the sustainability of new and existing urban settlements it is desirable to maximise the utilisation of the solar energy incident on the building envelope, whether by passive or active means. To this end we have coupled a multi-objective optimisation algorithm with the backwards ray tracing program RADIANCE which itself uses a cumulative sky model for the computation of incident irradiation (W h/m{sup 2}) in a single simulation. The parameters to optimise are geometric (the height of buildings up to their facade and the height and orientation of roofs), but with the constraint of maintaining an overall built volume, and the objective function is heating season solar irradiation offset by envelope heat losses. This methodology has been applied to a range of urban typologies and produces readily interpretable results. The focus of this work is on the design of new urban forms but the method could equally be applied to examine the relative efficiency of existing urban settlements, by comparison of existing forms with the calculated optima derived from relevant specifications of the building envelope. (author)

  6. Hafnium radioisotope recovery from irradiated tantalum

    DOE Patents [OSTI]

    Taylor, Wayne A. (Los Alamos, NM); Jamriska, David J. (Los Alamos, NM)

    2001-01-01

    Hafnium is recovered from irradiated tantalum by: (a) contacting the irradiated tantalum with at least one acid to obtain a solution of dissolved tantalum; (b) combining an aqueous solution of a calcium compound with the solution of dissolved tantalum to obtain a third combined solution; (c) precipitating hafnium, lanthanide, and insoluble calcium complexes from the third combined solution to obtain a first precipitate; (d) contacting the first precipitate of hafnium, lanthanide and calcium complexes with at least one fluoride ion complexing agent to form a fourth solution; (e) selectively adsorbing lanthanides and calcium from the fourth solution by cationic exchange; (f) separating fluoride ion complexing agent product from hafnium in the fourth solution by adding an aqueous solution of ferric chloride to obtain a second precipitate containing the hafnium and iron; (g) dissolving the second precipitate containing the hafnium and iron in acid to obtain an acid solution of hafnium and iron; (h) selectively adsorbing the iron from the acid solution of hafnium and iron by anionic exchange; (i) drying the ion exchanged hafnium solution to obtain hafnium isotopes. Additionally, if needed to remove residue remaining after the product is dried, dissolution in acid followed by cation exchange, then anion exchange, is performed.

  7. LWRS ATR Irradiation Testing Readiness Status

    SciTech Connect (OSTI)

    Kristine Barrett

    2012-09-01

    The Light Water Reactor Sustainability (LWRS) Program was established by the U.S. Department of Energy Office of Nuclear Energy (DOE-NE) to develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors. The LWRS Program is divided into four R&D Pathways: (1) Materials Aging and Degradation; (2) Advanced Light Water Reactor Nuclear Fuels; (3) Advanced Instrumentation, Information and Control Systems; and (4) Risk-Informed Safety Margin Characterization. This report describes an irradiation testing readiness analysis in preparation of LWRS experiments for irradiation testing at the Idaho National Laboratory (INL) Advanced Test Reactor (ATR) under Pathway (2). The focus of the Advanced LWR Nuclear Fuels Pathway is to improve the scientific knowledge basis for understanding and predicting fundamental performance of advanced nuclear fuel and cladding in nuclear power plants during both nominal and off-nominal conditions. This information will be applied in the design and development of high-performance, high burn-up fuels with improved safety, cladding integrity, and improved nuclear fuel cycle economics

  8. Figure 11 shows the reference irradiance spectrum proposed by Thuillier et al Figure 12 shows the Kitt Peak absolute irradiance spectrum smoothed using a 0.5

    E-Print Network [OSTI]

    Kurucz, Robert L.

    Figure 11 shows the reference irradiance spectrum proposed by Thuillier et al (2004). Figure 12 shows the Kitt Peak absolute irradiance spectrum smoothed using a 0.5 nm triangular bandpass irradiance spectrum subjectively normalized to the Thuillier et al irradiance spectrum. I recommend

  9. Final Report on MEGAPIE Target Irradiation and Post-Irradiation Examination

    SciTech Connect (OSTI)

    Yong, Dai

    2015-06-30

    Megawatt pilot experiment (MEGAPIE) was successfully performed in 2006. One of the important goals of MEGAPIE is to understand the behaviour of structural materials of the target components exposed to high fluxes of high-energy protons and spallation neutrons in flowing LBE (liquid lead-bismuth eutectic) environment by conducting post-irradiation examination (PIE). The PIE includes four major parts: non-destructive test, radiochemical analysis of production and distribution of radionuclides produced by spallation reaction in LBE, analysis of LBE corrosion effects on structural materials, T91 and SS 316L steels, and mechanical testing of the T91 and SS 316L steels irradiated in the lower part of the target. The non-destructive test (NDT) including visual inspection and ultrasonic measurement was performed in the proton beam window area of the T91 calotte of the LBE container, the most intensively irradiated part of the MEGAPIE target. The visual inspection showed no visible failure and the ultrasonic measurement demonstrated no detectable change in thickness in the beam window area. Gamma mapping was also performed in the proton beam window area of the AlMg3 safety-container. The gamma mapping results were used to evaluate the accumulated proton fluence distribution profile, the input data for determining irradiation parameters. Radiochemical analysis of radionuclides produced by spallation reaction in LBE is to improve the understanding of the production and distribution of radionuclides in the target. The results demonstrate that the radionuclides of noble metals, 207Bi, 194Hg/Au are rather homogeneously distributed within the target, while radionuclides of electropositive elements are found to be deposited on the steel-LBE interface. The corrosion effect of LBE on the structural components under intensive irradiation was investigated by metallography. The results show that no evident corrosion damages. However, unexpected deep cracks were found in the EBW (electron beam weld) of the LBE container in the intensive irradiation zone of the target, which should be formed during irradiation. In the SS 316L steel of the flow guide tube, inclusions or precipitates enriched with O, Si, S, Ca, Ti and Mn were observed. Many of them are very long, up to a few mm, and located on grain boundaries along the extrusion direction of the tube. The degradation of the mechanical properties of the T91 and SS 316L steels has been investigated by conducting tensile tests on the specimens extracted from the T91 and SS 316L components in the intensive irradiation region. The results obtained from the proton beam window of the T91 calotte exhibit a good ductility of T91 steel after irradiation at 6-7 dpa (displacement per atom) in contact with flowing LBE.

  10. The Effects of Irradiance in Determining the Vertical Distribution of Elk Kelp Pelagophycus porra

    E-Print Network [OSTI]

    Fejtek, Stacie Michelle

    2008-01-01

    microscopic stages to higher irradiances appears to be theH. (1996). “Effect of high irradiance on recruitment of theTHESIS The Effects of Irradiance in Determining the Vertical

  11. EFFECT OF EXCIMER LASER IRRADIATION OF BIODEGRADABLE POLYMER ON ITS CHEMICAL BONDING

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    EFFECT OF EXCIMER LASER IRRADIATION OF BIODEGRADABLE POLYMER ON ITS CHEMICAL BONDING Paper M1306 profile is favorable for surface treatment. The effects of excimer laser irradiation on the surface irradiation as a hea

  12. A comparison of DNA damage probes in two HMEC lines with X-irradiation

    E-Print Network [OSTI]

    Wisnewski, Christy L.; Bjornstad, Kathleen A.; Rosen, Christoper J.; Chang, Polly Y.; Blakely, Eleanor A.

    2008-01-01

    IN TWO HMEC LINES WITH X-IRRADIATION CHRISTY L. WISNEWSKI,prior to the experiment. Irradiation Four well LabTek slidesVictoreen probe 154. Following irradiation, slides or dishes

  13. SUBTHRESHOLD DISPLACEMENT DAMAGE IN COPPER-ALUMINUM ALLOYS DURING ELECTRON IRRADIATION

    E-Print Network [OSTI]

    Drosd, R.

    2010-01-01

    ALLOYS DURING ELECTRON IRRADIATION R. Drosd, T. Kosel, andALLOYS DURING ELECTRON IRRADIATION R. Drosd, T. Kosel and J.ABSTRACT During electron irradiation at low energies which

  14. Heavy-Ion Irradiation of Thulium(III) Oxide Targets Prepared by Polymer-Assisted Deposition

    E-Print Network [OSTI]

    Garcia, Mitch A.

    2008-01-01

    Heavy-Ion Irradiation of Thulium(III) Oxide Targets PreparedRMS) roughness prior to irradiation is 1.1 nm for a ~250roughness of 2.0 nm after irradiation was measured by atomic

  15. SHORT COMMUNICATION UV microspot irradiator at Columbia University

    E-Print Network [OSTI]

    Brenner, David Jonathan

    available for radiation biology research at the Radiological Research Accelerator Facility (RARAF), Columbia: 26 May 2013 Ó Springer-Verlag Berlin Heidelberg 2013 Abstract The Radiological Research Accelerator Facility at Columbia University has recently added a UV microspot irradiator to a microbeam irradiation

  16. IRRADIANCE MAPS APPLIED FOR THE PERFORMANCE ASSESSMENT OF PV SYSTEMS

    E-Print Network [OSTI]

    Heinemann, Detlev

    FEDERAL STATE OF SAXONY 1 Institute of Electrical Engineering,University of Applied Sciences (FH energy yield of a PV system,methods based on irradiance maps published by weather services or others of the irradiance data has been done by checking a set of monthly energy yield data of well-running grid

  17. Fowler-Nordheim characteristics of electron irradiated MOS capacitors

    SciTech Connect (OSTI)

    Candelori, A.; Paccagnella, A.; Cammarata, M.; Ghidini, G.; Fuochi, P.G.

    1998-12-01

    MOS capacitors with 8 nm thick oxides have been irradiated by an 8 MeV LINAC electron beam. C-V and I-V measurements have shown a positive trapped charge, higher for irradiation performed under negative gate bias, as a consequence of preferential charge recombination at the cathodic interface. No saturation of the positive trapped charge is measured up to 20 Mrad(Si). Neutral defects induced by irradiation have been studied, by performing positive and negative Fowler-Nordheim injection. The distribution of neutral defects is similar to that of trapped holes, indicating a correlation between trapped holes and neutral defects. Electrical stresses performed after irradiation have shown that the accumulation kinetics of oxide defects is similar in both unirradiated and irradiated devices.

  18. Identifying irradiated flours by photo-stimulated luminescence technique

    SciTech Connect (OSTI)

    Ramli, Ros Anita Ahmad; Yasir, Muhamad Samudi; Othman, Zainon; Abdullah, Wan Saffiey Wan

    2014-02-12

    Photo-stimulated luminescence (PSL) technique was used in this study to detect gamma irradiation treatment of five types of flours (corn, rice, tapioca, wheat and glutinous rice) at four different doses 0, 0.2, .05 and 1kGy. The signal level was compared with two threshold values (700 and 5000). With the exception of glutinous rice, all irradiated samples produced a strong signal above the upper threshold (5000 counts/60s). All control samples produced negative result with the signals below the lower threshold (700 counts/60s) suggesting that the samples have not been irradiated. Irradiated glutinous rice samples produced intermediate signals (700 - 5000 counts/60s) which were subsequently confirmed using calibrated PSL. The PSL signals remained stable after 90 days of storage. The findings of this study will be useful to facilitate control of food irradiation application in Malaysia.

  19. Frequency variations of quasi-periodic ELF-VLF emissions: A possible new ground-based diagnostic of the outer high-latitude magnetosphere

    SciTech Connect (OSTI)

    Alford, J.; Engebretson, M. [Ausburg College, Minneapolis, MN (United States)] [Ausburg College, Minneapolis, MN (United States); Arnoldy, R. [Univ. of New Hampshire, Durham, NH (United States)] [Univ. of New Hampshire, Durham, NH (United States); Inan, U. [Stanford Univ., CA (United States)] [Stanford Univ., CA (United States)

    1996-01-01

    Magnetic pulsations and quasi-periodic (QP) amplitude modulations of ELF-VLF waves at Pc 3-4 frequencies (15-50 mHz) are commonly observed simultaneously in cusp-latitude data. The naturally occurring ELF-VLF emissions are believed to be modulated within the magnetosphere by the compressional component of geomagnetic pulsations formed external to the magnetosphere. The authors have examined data from South Pole Station (L {approximately} 14) to determine the occurrence and characteristics of QP emissions. On the basis of 14 months of data during 1987 and 1988 they found that QP emissions typically appeared in both the 0.5-1 kHz and 1-2 kHz receiver channels at South Pole Station and ocassionally in the 2-4 kHz channel. The QP emission frequency appeared to depend on solar wind parameters and interplanetary magnetic field (IMF) direction, and the months near fall equinox in both 1987 and 1988 showed a significant increase in the percentage of QP emissions only in the lowest-frequency channel. The authors present a model consistent with these variations in which high-latitude (nonequatorial) magnetic field minima near the magnetopause play a major role, because the field magnitude governs both the frequency of ELF-VLF emissions and the whistler mode propagation cutoffs. Because the field in these regions will be strongly influenced by solar wind and IMF parameters, variations in the frequency of such emissions may be useful in providing ground-based diagnostics of the outer high-latitude magnetosphere. 32 refs., 13 figs.

  20. A Near-Infrared Photometric Study of the Low Latitude Globular Clusters Liller 1, Djorgovski 1, HP 1, and NGC 6528

    E-Print Network [OSTI]

    T. J. Davidge

    1999-09-23

    Images recorded through J, H, Ks, 2.2 micron continuum, and 2.3 micron CO filters are used to investigate the stellar contents of the low Galactic latitude globular clusters NGC 6528, Liller 1, Djorgovski 1, and HP 1, as well as surrounding bulge fields. Metallicities are estimated for the latter three clusters by comparing the colors and CO indices of giant branch stars with those in other clusters and the bulge, while reddenings are estimated from the colors of bright bulge stars in the surrounding fields. In some cases the metallicities and reddenings are significantly different from previous estimates.

  1. Analyzing and simulating the variability of solar irradiance and solar PV powerplants

    E-Print Network [OSTI]

    Lave, Matthew S.

    2012-01-01

    Models of diffuse solar radiation, Renew Energ, 33 (2008) [solar irradiance for analyzing areally- totalized PV systems, Sol Energsolar irradiance for analyzing areally- totalized PV systems, Sol Energ

  2. Solar irradiance forecasting at multiple time horizons and novel methods to evaluate uncertainty

    E-Print Network [OSTI]

    Marquez, Ricardo

    2012-01-01

    From the k(t + 1) predictions, solar irradiance forecastsand M. Cony. Prediction of global solar irradiance based onand A. E. Ruano. Prediction of the solar radiation evolution

  3. A high-resolution, cloud-assimilating numerical weather prediction model for solar irradiance forecasting

    E-Print Network [OSTI]

    Mathiesen, Patrick; Collier, Craig; Kleissl, Jan

    2013-01-01

    of numerical weather prediction solar irradiance forecasts numerical weather prediction model for solar irradiance weather prediction for intra?day solar  forecasting in the 

  4. X. CORRELATIONS BETWEEN DIFFUSE AND GLOBAL IRRADIANCE For numerous applications, particularly those

    E-Print Network [OSTI]

    Oregon, University of

    33 X. CORRELATIONS BETWEEN DIFFUSE AND GLOBAL IRRADIANCE For numerous applications, particularly these components, values for direct beam and diffuse irradiance are usu- ally unavailable. However, considerable in

  5. IRRADIATION GROWTH IN ZIRCONIUM AT LOW TEMPERATURES BY DIRECT ATHERMAL DEPOSITION OF VACANCIES AT EXTENDED SINKS

    E-Print Network [OSTI]

    Motta, Arthur T.

    IRRADIATION GROWTH IN ZIRCONIUM AT LOW TEMPERATURES BY DIRECT ATHERMAL DEPOSITION OF VACANCIES, which can contribute to the observed growth strains. 1. Introduction Irradiation growth of zirconium

  6. Characteristics of Non-Irradiated and Irradiated Double SOI Integration Type Sensor

    E-Print Network [OSTI]

    Asano, Mari; Sekigawa, Daisuke; Honda, Shunsuke; Tobita, Naoshi; Arai, Yasuo; Miyoshi, Toshinobu; Kurachi, Ikuo

    2015-01-01

    We are developing monolithic pixel sensors based on a 0.2 $\\mu$m fully-depleted Silicon-on-Insulator (SOI) technology for HEP experiment applications. The total ionizing dose (TID) effect is the major issue in the applications for hard radiation environments in HEP experiments. To compensate for TID damage, we have introduced a Double SOI structure which has a Middle Silicon layer (SOI2 layer) in addition. We studied the recovery from TID damage induced by $\\mathrm{^{60}Co}~\\gamma$'s and other characteristics of an Integration-type Double SOI sensor. The Double SOI sensor irradiated to 100 kGy showed a response for IR laser similar to of a non-irradiated sensor when we applied a negative voltage to the SOI2 layer. We conclude that the Double SOI sensor is radiation hard enough to be used in HEP experiments in harsh radiation environments such as at Bell II or ILC.

  7. Breakdown properties of irradiated MOS capacitors

    SciTech Connect (OSTI)

    Paccagnella, A.; Candelori, A.; Milani, A.; Formigoni, E.; Ghidini, G.; Drera, D.; Pellizzer, F.; Fuochi, P.G.; Lavale, M.

    1996-12-01

    The authors have studied the effects of ionizing and non-ionizing radiation on the breakdown properties of different types of MOS capacitors, with thick (200 nm) and thin (down to 8 nm) oxides. In general, no large variations of the average breakdown field, time-to-breakdown at constant voltage, or charge-to-breakdown at constant voltage, or charge-to-breakdown values have been observed after high dose irradiation (20 Mrad(Si) 9 MeV electrons on thin and thick oxides, 17(Si) Mrad Co{sup 60} gamma and 10{sup 14} neutrons/cm{sup 2} only on thick oxides). However, some modifications of the cumulative failure distributions have been observed in few of the oxides tested.

  8. Instrumentation to Enhance Advanced Test Reactor Irradiations

    SciTech Connect (OSTI)

    J. L. Rempe; D. L. Knudson; K. G. Condie; J. E. Daw; S. C. Taylor

    2009-09-01

    The Department of Energy (DOE) designated the Advanced Test Reactor (ATR) as a National Scientific User Facility (NSUF) in April 2007 to support U.S. leadership in nuclear science and technology. By attracting new research users - universities, laboratories, and industry - the ATR will support basic and applied nuclear research and development, further advancing the nation's energy security needs. A key component of the ATR NSUF effort is to prove new in-pile instrumentation techniques that are capable of providing real-time measurements of key parameters during irradiation. To address this need, an assessment of instrumentation available and under-development at other test reactors has been completed. Based on this review, recommendations are made with respect to what instrumentation is needed at the ATR and a strategy has been developed for obtaining these sensors. Progress toward implementing this strategy is reported in this document. It is anticipated that this report will be updated on an annual basis.

  9. Optimization parameter design for proton irradiation accelerator

    E-Print Network [OSTI]

    Yu-Wen An; Hong-Fei Ji; Sheng Wang; Shou-Yan Xu

    2014-11-20

    The proton irradiation accelerator is widely founded for industry application, and should be designed as compact, reliable, and easy operate. A 10 MeV proton beam is designed to be injected into the slow circulation ring with the repetition rate of 0.5 Hz for accumulation and acceleration, and then the beam with the energy of 300MeV will be slowly extracted by third order resonance method. For getting a higher intensity and more uniform beam, the height of the injection bump is carefully optimised during the injection period. Besides, in order to make the extracted beam with a more uniform distribution, a RF Knock-out method is adopted, and the RF kicker's amplitude is well optimised.

  10. Recovery of niobium from irradiated targets

    DOE Patents [OSTI]

    Phillips, Dennis R. (Los Alamos, NM); Jamriska, Sr., David J. (Los Alamos, NM); Hamilton, Virginia T. (Los Alamos, NM)

    1994-01-01

    A process for selective separation of niobium from proton irradiated molybdenum targets is provided and includes dissolving the molybdenum target in a hydrogen peroxide solution to form a first ion-containing solution, contacting the first ion-containing solution with a cationic resin whereby ions selected form the group consisting of molybdenum, biobium, technetium, selenium, vanadium, arsenic, germanium, zirconium and rubidium remain in a second ion-containing solution while ions selected from the group consisting of rubidium, zinc, beryllium, cobalt, iron, manganese, chromium, strontium, yttrium and zirconium are selectively adsorbed by the cationic resin; adjusting the pH of the second ion-containing solution to within a range of from about 5.0 to about 6.0; contacting the pH adjusting second ion-containing solution with a dextran-based material for a time to selectively separate niobium from the solution and recovering the niobium from the dextran-based material.

  11. Irradiation effect on deuterium behaviour in low-dose HFIR neutron-irradiated tungsten

    SciTech Connect (OSTI)

    Shimada, Masashi; Cao, G.; Otsuka, T.; Hara, M.; Kobayashi, M.; Oya, Y.; Hatano, Y.

    2014-12-01

    Tungsten samples were irradiated by neutrons in the High Flux Isotope Reactor, Oak Ridge National Laboratory at reactor coolant temperatures of 50-70°C to low displacement damage of 0.025 and 0.3 dpa under the framework of the US-Japan TITAN program (2007-2013). After cooling down, the HFIR neutron-irradiated tungsten samples were exposed to deuterium plasmas in the Tritium Plasma Experiment, Idaho National Laboratory at 100, 200 and 500 °C twice at the ion fluence of 5×10²? m?² to reach a total ion fluence of 1×10²? m?² in order to investigate the near surface deuterium retention and saturation via nuclear reaction analysis. Final thermal desorption spectroscopy was performed to elucidate irradiation effect on total deuterium retention. Nuclear reaction analysis results showed that the maximum near surface (<5 µm depth) deuterium concentration increased from 0.5 at % D/W in 0.025 dpa samples to 0.8 at. % D/W in 0.3 dpa samples. The large discrepancy between the total retention via thermal desorption spectroscopy and the near surface retention via nuclear reaction analysis indicated the deuterium was migrated and trapped in bulk (at least 50 µm depth for 0.025 dpa and 35 µm depth for 0.025 dpa) at 500 °C case even in the relatively low ion fluence of 10²? m?².

  12. AGC-1 Pre-Irradiation Data Report Status

    SciTech Connect (OSTI)

    William Windes

    2011-08-01

    The Next Generation Nuclear Plant (NGNP) Graphite R&D program is currently measuring irradiated material property changes in several grades of nuclear graphite for predicting their behavior and operating performance within the core of new Very High Temperature Reactor (VHTR) designs. The Advanced Graphite Creep (AGC) experiment consisting of six irradiation capsules will generate this irradiated graphite performance data for NGNP reactor operating conditions. All samples in the experiment will be fully characterized before irradiation, irradiated in the Advanced Test Reactor (ATR), and then re-examined to determine the irradiation induced changes to key materials properties in the different graphite grades. The information generated during the AGC experiment will be utilized for NRC licensing of NGNP reactor designs, shared with international collaborators in the Generation IV Information Forum (GIF), and eventually utilized in ASME design code for graphite nuclear applications. This status report will describe the process the NGNP Graphite R&D program has developed to record the AGC1 pre-irradiation examination data.

  13. Dynamic Void Growth and Shrinkage in Mg under Electron Irradiation

    SciTech Connect (OSTI)

    Xu, W. Z. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering; Zhang, Y. F. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Cheng, G. M. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering; Jian, W. W. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering; Millett, P. C. [Univ. of Arkansas, Fayetteville, AR (United States). Dept. of Mecanical Engineering; Koch, C. C. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering; Mathaudhu, S. N. [U.S. Army Research Office, Research Triangle Park, NC (United States). Materials Science Division; Zhu, Y. T. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering

    2014-04-30

    We report in-situ atomic-scale investigation of void evolution, including growth, coalescence and shrinkage, under electron irradiation. With increasing irradiation dose, the total volume of voids increased linearly, while nucleation rate of new voids decreased slightly, and the total number of voids decreased. Some voids continued to grow while others shrank to disappear, depending on the nature of their interactions with nearby self-interstitial loops. For the first time, surface diffusion of adatoms was observed largely responsible for the void coalescence and thickening. These findings provide fundamental understanding to help with the design and modeling of irradiation-resistant materials.

  14. Indoor and Outdoor Spectroradiometer Intercomparison for Spectral Irradiance Measurement

    SciTech Connect (OSTI)

    Habte, A.; Andreas, A.; Ottoson, L.; Gueymard, C.; Fedor, G.; Fowler, S.; Peterson, J.; Naranen, R.; Kobashi, T.; Akiyama, A.; Takagi, S.

    2014-05-01

    This report details the global spectral irradiance intercomparison using spectroradiometers that was organized by the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. The intercomparison was performed both indoors and outdoors on September 17, 2013. Five laboratories participated in the intercomparison using 10 spectroradiometers, and a coordinated measurement setup and a common platform were employed to compare spectral irradiances under both indoor and outdoor conditions. The intercomparison aimed to understand the performance of the different spectroradiometers and to share knowledge in making spectral irradiance measurements. This intercomparison was the first of its kind in the United States.

  15. Reconstruction of solar irradiance using the Group sunspot number

    E-Print Network [OSTI]

    L. Balmaceda; N. A. Krivova; S. K. Solanki

    2007-03-07

    We present a reconstruction of total solar irradiance since 1610 to the present based on variations of the surface distribution of the solar magnetic field. The latter is calculated from the historical record of the Group sunspot number using a simple but consistent physical model. Our model successfully reproduces three independent data sets: total solar irradiance measurements available since 1978, total photospheric magnetic flux from 1974 and the open magnetic flux since 1868 (as empirically reconstructed from the geomagnetic aa-index). The model predicts an increase in the total solar irradiance since the Maunder Minimum of about 1.3 \\rm{Wm$^{-2}$}.

  16. Viability of adult rat skin following 13 Mev proton irradiation 

    E-Print Network [OSTI]

    Caraway, Bobby Lamar

    1966-01-01

    alteration resulting from total skin proton irradiation seemed to be dose related. Therefore, since the amount of tissue alteration seems to be dose-dependent, a hypothesis was developed that growth and viability of skin cells removed' by biopsy... rats each were subjected to total-skin proton irradiation of varying doses. The dose varied from 1300 rad in Group I to 200 rad in Group 1V. Two rats from each group served as controls and received no irradiation. Five days and 30 days...

  17. Early Damage Mechanisms in Nuclear Grade Graphite under Irradiation

    SciTech Connect (OSTI)

    Eapen, Dr. Jacob [North Carolina State University] [North Carolina State University; Krishna, Dr Ram [North Carolina State University] [North Carolina State University; Burchell, Timothy D [ORNL] [ORNL; Murty, Prof K.L. [North Carolina State University] [North Carolina State University

    2014-01-01

    Using Raman and X-ray photoelectron spectroscopy,we delineate the bond and defect structures in nuclear block graphite (NBG-18) under neutron and ion irradiation. The strengthening of the defect (D) peak in the Raman spectra under irradiation is attributed to an increase in the topological, sp2-hybridized defects. Using transmission electron microscopy, we provide evidence for prismatic dislocations as well as a number of basal dislocations dissociating into Shockley partials. The non-vanishing D peak in the Raman spectra, together with a generous number of dislocations, even at low irradiation doses, indicates a dislocation-mediated amorphization process in graphite.

  18. Measurement of thermal conductivity in proton irradiated silicon

    SciTech Connect (OSTI)

    Marat Khafizov; Clarissa Yablinsky; Todd Allen; David Hurley

    2014-04-01

    We investigate the influence of proton irradiation on thermal conductivity in single crystal silicon. We apply laser based modulated thermoreflectance technique to extract the change in conductivity of the thin layer damaged by proton irradiation. Unlike time domain thermoreflectance techniques that require application of a metal film, we perform our measurement on uncoated samples. This provides greater sensitivity to the change in conductivity of the thin damaged layer. Using sample temperature as a parameter provides a means to deduce the primary defect structures that limit thermal transport. We find that under high temperature irradiation the degradation of thermal conductivity is caused primarily by extended defects.

  19. Concurrent in situ ion irradiation transmission electron microscope

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

    Hattar, K.; Bufford, D. C.; Buller, D. L.

    2014-08-29

    An in situ ion irradiation transmission electron microscope has been developed and is operational at Sandia National Laboratories. This facility permits high spatial resolution, real time observation of electron transparent samples under ion irradiation, implantation, mechanical loading, corrosive environments, and combinations thereof. This includes the simultaneous implantation of low-energy gas ions (0.8–30 keV) during high-energy heavy ion irradiation (0.8–48 MeV). In addition, initial results in polycrystalline gold foils are provided to demonstrate the range of capabilities.

  20. AGC-2 Irradiation Data Qualification Final Report

    SciTech Connect (OSTI)

    Laurence C. Hull

    2012-07-01

    The Graphite Technology Development Program will run a series of six experiments to quantify the effects of irradiation on nuclear grade graphite. The second Advanced Graphite Creep (AGC) experiment (AGC-2) began with Advanced Test Reactor (ATR) Cycle 149A on April 12, 2011, and ended with ATR Cycle 151B on May 5, 2012. The purpose of this report is to qualify AGC-2 irradiation monitoring data following INL Management and Control Procedure 2691, Data Qualification. Data that are Qualified meet the requirements for data collection and use as described in the experiment planning and quality assurance documents. Data that do not meet the requirements are Failed. Some data may not quite meet the requirements, but may still provide some useable information. These data are labeled as Trend. No Trend data were identified for the AGC-2 experiment. All thermocouples functioned throughout the AGC-2 experiment. There was one instance where spurious signals or instrument power interruption resulted in a recorded temperature value being well outside physical reality. This value was identified and labeled as Failed data. All other temperature data are Qualified. All helium and argon gas flow data are within expected ranges. Total gas flow was approximately 50 sccm through the capsule. Helium gas flow was briefly increased to 100 sccm during reactor shutdown. All gas flow data are Qualified. At the start of the experiment, moisture in the outflow gas line increased to 200 ppmv then declined to less than 10 ppmv over a period of 5 days. This increase in moisture coincides with the initial heating of the experiment and drying of the system. Moisture slightly exceeded 10 ppmv three other times during the experiment. While these moisture values exceed the 10 ppmv threshold value, the reported measurements are considered accurate and to reflect moisture conditions in the capsule. All moisture data are Qualified. Graphite creep specimens are subjected to one of three loads, 393 lbf, 491 lbf, or 589 lbf. Loads were consistently within 5% of the specified values throughout the experiment. Stack displacement increased consistently throughout the experiment with total displacement ranging from 1 to 1.5 inches. No anomalous values were identified. During reactor outages, a set of pneumatic rams are used to raise the stacks of graphite creep specimens to ensure the specimens have not become stuck within the test train. This stack raising was performed after all cycles when the capsule was in the reactor. All stacks were raised successfully after each cycle. The load and displacement data are Qualified

  1. Reinforcing multiwall carbon nanotubes by electron beam irradiation Martial Duchamp,1

    E-Print Network [OSTI]

    Tománek, David

    Reinforcing multiwall carbon nanotubes by electron beam irradiation Martial Duchamp,1 Richard August 2010; published online 25 October 2010 We study the effect of electron beam irradiation-slip motion prior to irradiation, indicating presence of extended defects. Upon electron beam irradiation

  2. Intra-hour Direct Normal Irradiance solar forecasting using genetic programming

    E-Print Network [OSTI]

    Queener, Benjamin Daniel

    2012-01-01

    A. E. Ruano, “Prediction of the solar radiation evolutionin ground- level solar irradiance prediction on similar

  3. Optimum Inverter Sizing in Consideration of Irradiance Pattern and PV Incentives

    E-Print Network [OSTI]

    Lehman, Brad

    Optimum Inverter Sizing in Consideration of Irradiance Pattern and PV Incentives Song Chen* Peng Li is that irradiance levels in real installations only occasionally reach irradiance levels of the STC conditions (1000 some researchers propose that undersized inverters cause considerable energy loss under high irradiance

  4. IRRADIATION EFFECTS ON THE PHYSIO-MECHANICAL PROPERTIES OF SUPER-ALLOYS CHARACTERIZED BY LOW THERMAL

    E-Print Network [OSTI]

    McDonald, Kirk

    IRRADIATION EFFECTS ON THE PHYSIO-MECHANICAL PROPERTIES OF SUPER-ALLOYS CHARACTERIZED BY LOW and the associated irradiation damage, an experimental study has been undertaken to evaluate the potential- O) are observed in their un-irradiated state. Irradiations were performed using the 200 MeV protons

  5. Measurement and Modeling of Shortwave Irradiance Components in Cloud-Free Atmospheres

    E-Print Network [OSTI]

    Measurement and Modeling of Shortwave Irradiance Components in Cloud-Free Atmospheres Rangasayi to classify the earth-atmospheric solar radiation into several components - direct solar surface irradiance (Edirect), diffuse-sky downward surface irradiance (Ediffuse), total surface irradiance, and upwelling flux

  6. COMBINING SOLAR IRRADIANCE MEASUREMENTS AND VARIOUS SATELLITE-DERIVED PRODUCTS TO

    E-Print Network [OSTI]

    Heinemann, Detlev

    COMBINING SOLAR IRRADIANCE MEASUREMENTS AND VARIOUS SATELLITE-DERIVED PRODUCTS TO A SITE power plants depend strongly on the availability of beam irradiance. Direct solar irradiance is highly-series. In this paper, a satellite- retrieval for beam irradiance from the new generation is introduced and inter

  7. THE INFLUENCE OF MIXED-PHASE CLOUDS ON SURFACE SHORTWAVE IRRADIANCE DURING THE ARCTIC SPRING

    E-Print Network [OSTI]

    THE INFLUENCE OF MIXED-PHASE CLOUDS ON SURFACE SHORTWAVE IRRADIANCE DURING THE ARCTIC SPRING Dan-phase stratiform clouds on the surface shortwave irradiance is examined using spectral irradiance measurements from.) spectroradiometer measured downwelling spectral irradiance in the interval 350­2200 nm, in one-minute averages

  8. The influence of mixedphase clouds on surface shortwave irradiance during the Arctic spring

    E-Print Network [OSTI]

    The influence of mixedphase clouds on surface shortwave irradiance during the Arctic spring Dan irradiance is examined using unique spectral shortwave irradiance measurements made during the Indirect spectral irradiance from 350 to 2200 nm in oneminute averages throughout April­May 2008 from the ARM

  9. Accuracy improvement of irradiation data by combining ground and satellite measurements

    E-Print Network [OSTI]

    Heinemann, Detlev

    Accuracy improvement of irradiation data by combining ground and satellite measurements Jethro-Georg.Beyer@et.hs-magdeburg.de Introduction: · Planning, monitoring and operation of PV systems require accurate irradiation data · Knowledge of the accuracy improves the value of the irradiation data · Options to obtain site-specific irradiance data: 1

  10. Solar irradiance forecasting at multiple time horizons and novel methods to evaluate uncertainty

    E-Print Network [OSTI]

    Marquez, Ricardo

    2012-01-01

    Solar irradiance data . . . . . . . . . . . . .Accuracy . . . . . . . . . . . . . . . . . Solar Resourcev Uncertainty In Solar Resource: Forecasting

  11. Gap Junction Structures. IV. Revealed by Low-irradiation

    E-Print Network [OSTI]

    Baker, Timothy S.

    , and negatively stained with uranyl acetate, have been recorded by low-irradiation methods. Our Fourier- averaged with uranyl acetate, showed hexagonal shaped connexons arrayed with approximate mirror symmetry

  12. Carbon Characterization Laboratory Readiness to Receive Irradiated Graphite Samples

    SciTech Connect (OSTI)

    Karen A. Moore

    2011-05-01

    The Carbon Characterization Laboratory (CCL) is located in Labs C19 and C20 of the Idaho National Laboratory Research Center. The CCL was established under the Next Generation Nuclear Plant Project to support graphite and ceramic composite research and development activities. The research conducted in this laboratory will support the Advanced Graphite Creep experiments—a major series of material irradiation experiments within the Next Generation Nuclear Plant Graphite program. The CCL is designed to characterize and test low activated irradiated materials such as high purity graphite, carbon-carbon composites, silicon-carbide composite, and ceramic materials. The laboratory is fully capable of characterizing material properties for both irradiated and nonirradiated materials. Major infrastructural modifications were undertaken to support this new radiological facility at Idaho National Laboratory. Facility modifications are complete, equipment has been installed, radiological controls and operating procedures have been established and work management documents have been created to place the CCL in readiness to receive irradiated graphite samples.

  13. Crystal Irradiation Stimulation of Enzyme Reactivity: An Explanation

    E-Print Network [OSTI]

    George E. Bass

    2007-06-12

    In 1968, Sorin Comorosan first reported a phenomenon wherein irradiation of the substrate of an enzyme reaction, in the crystalline state, for a specific number of seconds could lead to an enhanced aqueous solution reaction rate for the enzyme(up to 30%). Dependence on crystal irradiation time was found to be oscillatory with a fixed period. The basis for this unusual phenomenon has remained a mystery. Previously unreported experimental results are presented which demonstrate, for the LDH / pyruvate reaction, that the identity of the crystalline material irradiated is, largely, inconsequential. It is proposed here that the irradiation procedure drives oscillatory reactions involving atmospheric gases adsorbed on the crystals and that these photoproducts, or related dark-reaction species, when dissolved, function as enzyme cofactors.

  14. Irradiation Stability of Carbon Nanotubes and Related Materials 

    E-Print Network [OSTI]

    Aitkaliyeva, Assel 1985-

    2012-09-28

    Application of carbon nanotubes (CNTs) in various fields demands a thorough investigation of their stability under irradiation. Open structure, ability to reorganize and heal defects, and large surface-to-volume ratio of carbon nanotubes affect...

  15. RETHINKING SATELLITE BASED SOLAR IRRADIANCE MODELLING R. W. Mueller

    E-Print Network [OSTI]

    Heinemann, Detlev

    into the electricity grid, accurate solar irradiance data in a high spatial and temporal resolution are necessary. Solar irra- diance schemes provide these data using weather satellites such as METEOSAT and MSG

  16. Lanai high-density irradiance sensor network for characterizing...

    Office of Scientific and Technical Information (OSTI)

    Lanai high-density irradiance sensor network for characterizing solar resource variability of MW-scale PV system. Citation Details In-Document Search Title: Lanai high-density...

  17. Irradiation facilities at the Los Alamos Meson Physics Facility

    SciTech Connect (OSTI)

    Sandberg, V.

    1990-01-01

    The irradiation facilities for testing SSC components and detector systems are described. Very high intensity proton, neutron, and pion fluxes are available with beam kinetic energies of up to 800 MeV. 4 refs., 12 figs., 2 tabs.

  18. MATERIAL IRRADIATION STUDIES BNL AGS/BLIP/Hot Cell FACILITY

    E-Print Network [OSTI]

    McDonald, Kirk

    BeMet Nickel-Plated Aluminum Mechanical property changes Ductility loss Strength loss/gain Fracture toughness (irradiated) GUM Metal Strengthens but clearly looses the "super-ductility property The type of gum metal

  19. Enhanced structural stability of nanoporous zirconia under irradiation of He

    SciTech Connect (OSTI)

    Yang, Tengfei; Huang, Xuejun; Wang, Chenxu; Zhang, Yanwen; Xue, Jianming; Yan, Sha; Wang, Yuguang

    2012-01-01

    This work reports a greatly enhanced tolerance for He irradiation-induced swelling in nanocrystalline zirconia film with interconnected nanoporous structure (hereinafter referred as to NC-C). Compared to bulk yttria-stabilized zirconia (YSZ) and another nanocrystalline zirconia film only with discrete nano voids (hereinafter referred as to NC-V), the NC-C film reveals good tolerance for irradiation of high-fluence He. No appreciable surface blistering can be found even at the highest fluence of 6 1017 cm2 in NCC film. From TEM analysis of as-irradiated samples, the enhanced tolerance for volume swelling in NCC film is attributed to the enhanced diffusion mechanism of deposited He via widely distributed nano channels. Furthermore, the growth of grain size is quite small for both nanocrystalline zirconia films after irradiation, which is ascribed to the decreasing of area of grain boundary due to loose structure and low energy of primary knock-on atoms for He ions.

  20. Irradiation Assisted Grain Boundary Segregation in Steels

    SciTech Connect (OSTI)

    Lu, Zheng; Faulkner, Roy G.

    2008-07-01

    The understanding of radiation-induced grain boundary segregation (RIS) has considerably improved over the past decade. New models have been introduced and much effort has been devoted to obtaining comprehensive information on segregation from the literature. Analytical techniques have also improved so that chemical analysis of layers 1 nm thick is almost routine. This invited paper will review the major methods used currently for RIS prediction: namely, Rate Theory, Inverse Kirkendall, and Solute Drag approaches. A summary is made of the available data on phosphorus RIS in reactor pressure vessel (RPV) steels. This will be discussed in the light of the predictions of the various models in an effort to show which models are the most reliable and easy to use for forecasting P segregation behaviour in steels. A consequence of RIS in RPV steels is a radiation induced shift in the ductile to brittle transition temperature (DBTT). It will be shown how it is possible to relate radiation-induced P segregation levels to DBTT shift. Examples of this exercise will be given for RPV steels and for ferritic steels being considered for first wall fusion applications. Cr RIS in high alloy stainless steels and associated irradiation-assisted stress corrosion cracking (IASCC) will be briefly discussed. (authors)

  1. Recovery of germanium-68 from irradiated targets

    DOE Patents [OSTI]

    Phillips, Dennis R. (Los Alamos, NM); Jamriska, Sr., David J. (Los Alamos, NM); Hamilton, Virginia T. (Los Alamos, NM)

    1993-01-01

    A process for selective separation of germanium-68 from proton irradiated molybdenum targets is provided and includes dissolving the molybdenum target in a hydrogen peroxide solution to form a first ion-containing solution, contacting the first ion-containing solution with a cationic resin whereby ions selected from the group consisting of molybdenum, niobium, technetium, selenium, vanadium, arsenic, germanium, zirconium and rubidium remain in a second ion-containing solution while ions selected from the group consisting of rubidium, zinc, beryllium, cobalt, iron, manganese, chromium, strontium, yttrium and zirconium are selectively adsorbed by the first resin, adjusting the pH of the second ion-containing solution to within a range of from about 0.7 to about 3.0, adjusting the soluble metal halide concentration in the second ion-containing solution to a level adapted for subsequent separation of germanium, contacting the pH-adjusted, soluble metal halide-containing second ion-containing solution with a dextran-based material whereby germanium ions are separated by the dextran-based material, and recovering the germanium from the dextran-based material, preferably by distillation.

  2. Influence of irradiation upon few-layered graphene using electron-beams and gamma-rays

    SciTech Connect (OSTI)

    Wang, Yuqing; Feng, Yi, E-mail: fyhfut@163.com; Mo, Fei; Qian, Gang; Chen, Yangming; Yu, Dongbo; Wang, Yang; Zhang, Xuebin [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China)

    2014-07-14

    Few-layered graphene (FLG) is irradiated by electron beams and gamma rays. After 100?keV electron irradiation, the edges of FLG start bending, shrinking, and finally generate gaps and carbon onions due to sputtering and knock-on damage mechanism. When the electron beam energy is increased further to 200?keV, FLG suffers rapid and catastrophic destruction. Unlike electron irradiation, Compton effect is the dominant damage mechanism in gamma irradiation. The irradiation results indicate the crystallinity of FLG decreases first, then restores as increasing irradiation doses, additionally, the ratio (O/C) of FLG surface and the relative content of oxygen groups increases after irradiation.

  3. Sodium and potassium levels in the serum of acutely irradiated and non-irradiated rats 

    E-Print Network [OSTI]

    Shepherd, David Preston

    1967-01-01

    . The rats were exposed separately for a period of two minutes. The dose rate measurements were determined prior to this study by using lithium fluoride dosimeter s, and were brought up to date by calculation. Twenty-four hours before irradiation, one ml... carbonate 10 drops Magnesium sulfate 25 mgm Manganese sulfate 7. 5 mgm Iron phosphate 500 gm Sodium fluoride 1 mgm Potassium iodide 25 mcgm Potassium phosphate 1 mgm Potassium chloride 10 mgm 10 mgm Copper Sulfate 40 rngm Aluminum potassium s ul...

  4. Lymphocyte depletion in peripheral blood of gamma irradiated rats 

    E-Print Network [OSTI]

    Goldin, Eric Michael

    1972-01-01

    LYMPHOCYTE DEPLETION IN PERIPHERAL BLOOD OF GAMMA IRRADIATED RATS A Thesis by ERIC MICHAEL GOLDIN Submitted to the Graduate College of Texas ABM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... December 1972 Major Subject: Nuclear Engineering (Health Physics) LYMPHOCYTE DEPLETION IN PERIPHERAL BLOOD OF GAMMA IRRADIATED RATS A Thesis by ERIC MICHAEL GOLDIN Approved as to sty1e and con ent by: ( hairman of Co it ee) (H of Depar ment...

  5. Thermoluminescence and dielectric response of gamma irradiated muscovite mica

    SciTech Connect (OSTI)

    Kaur, Sukhnandan, E-mail: sukhnandanphy@gmail.com; Singh, Surinder, E-mail: sukhnandanphy@gmail.com; Singh, Lakhwant, E-mail: sukhnandanphy@gmail.com [Department of Physics, Guru Nanak Dev University, Amritsar-143005 (India); Lochab, S. P. [Inter University Accelerator Centre, New Delhi-110067 (India)

    2014-04-24

    The effect of gamma radiation dose on the thermoluminescence (TL) and dielectric properties of muscovite mica was studied. TL glow curves exhibited a single peak around 141 {sup 0}C and its activation energy was estimated to be about 0.89 eV. Different dielectric parameters like dielectric constant, dielectric loss and ac conductivity have been calculated in both pristine and gamma irradiated samples. These dielectric parameters have been studied as a function of irradiation dose.

  6. Ion irradiation testing of Improved Accident Tolerant Cladding Materials

    SciTech Connect (OSTI)

    Anderoglu, Osman [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tesmer, Joseph R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Maloy, Stuart A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-14

    This report summarizes the results of ion irradiations conducted on two FeCrAl alloys (named as ORNL A&B) for improving the accident tolerance of LWR nuclear fuel cladding. After irradiation with 1.5 MeV protons to ~0.5 to ~1 dpa and 300°C nanoindentations were performed on the cross-sections along the ion range. An increase in hardness was observed in both alloys. Microstructural analysis shows radiation induced defects.

  7. Heavy-ion irradiation induced diamond formation in carbonaceous materials.

    SciTech Connect (OSTI)

    Daulton, T. L.

    1999-01-08

    The basic mechanisms of metastable phase formation produced under highly non-equilibrium thermodynamic conditions within high-energy particle tracks are investigated. In particular, the possible formation of diamond by heavy-ion irradiation of graphite at ambient temperature is examined. This work was motivated, in part, by earlier studies which discovered nanometer-grain polycrystalline diamond aggregates of submicron-size in uranium-rich carbonaceous mineral assemblages of Precambrian age. It was proposed that the radioactive decay of uranium formed diamond in the fission particle tracks produced in the carbonaceous minerals. To test the hypothesis that nanodiamonds can form by ion irradiation, fine-grain polycrystalline graphite sheets were irradiated with 400 MeV Kr ions. The ion irradiated graphite (and unirradiated graphite control) were then subjected to acid dissolution treatments to remove the graphite and isolate any diamonds that were produced. The acid residues were then characterized by analytical and high-resolution transmission electron microscopy. The acid residues of the ion-irradiated graphite were found to contain ppm concentrations of nanodiamonds, suggesting that ion irradiation of bulk graphite at ambient temperature can produce diamond.

  8. Initiate test loop irradiations of ALSEP process solvent

    SciTech Connect (OSTI)

    Peterman, Dean R. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Olson, Lonnie G. [Idaho National Lab. (INL), Idaho Falls, ID (United States); McDowell, Rocklan G. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    This report describes the initial results of the study of the impacts of gamma radiolysis upon the efficacy of the ALSEP process and is written in completion of milestone M3FT-14IN030202. Initial irradiations, up to 100 kGy absorbed dose, of the extraction section of the ALSEP process have been completed. The organic solvent used for these experiments contained 0.05 M TODGA and 0.75 M HEH[EHP] dissolved in n-dodecane. The ALSEP solvent was irradiated while in contact with 3 M nitric acid and the solutions were sparged with compressed air in order to maintain aerated conditions. The irradiated phases were used for the determination of americium and europium distribution ratios as a function of absorbed dose for the extraction and stripping conditions. Analysis of the irradiated phases in order to determine solvent composition as a function of absorbed dose is ongoing. Unfortunately, the failure of analytical equipment necessary for the analysis of the irradiated samples has made the consistent interpretation of the analytical results difficult. Continuing work will include study of the impacts of gamma radiolysis upon the extraction of actinides and lanthanides by the ALSEP solvent and the stripping of the extracted metals from the loaded solvent. The irradiated aqueous and organic phases will be analyzed in order to determine the variation in concentration of solvent components with absorbed gamma dose. Where possible, radiolysis degradation product will be identified.

  9. Irradiation-Assisted Stress Corrosion Cracking of Austenitic Stainless Steels and Alloy 690 from Halden Phase-II Irradiations

    SciTech Connect (OSTI)

    Chen, Y.; Chopra, O. K.; Soppet, W. K.; Dietz Rago, Nancy L.; Shack, W. J.

    2008-09-01

    This work is an ongoing effort at Argonne National Laboratory on the mechanistic study of irradiation-assisted stress corrosion cracking (IASCC) in the core internals of light water reactors.

  10. The effects of tungsten's pre-irradiation surface condition on helium-irradiated morphology

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

    Garrison, Lauren M.; Kulcinski, Gerald L.

    2015-07-17

    Erosion is a concern associated with the use of tungsten as a plasma-facing component in fusion reactors. To compare the damage progression, polycrystalline tungsten (PCW) and (110) single crystal tungsten (SCW) samples were prepared with (1) a mechanical polish (MP) with roughness values in the range of 0.018–0.020 ?m and (2) an MP and electropolish (MPEP) resulting in roughness values of 0.010–0.020 ?m for PCW and 0.003–0.005 ?m for SCW samples. Samples were irradiated with 30 keV He+ at 1173 K to fluences between 3 × 1021 and 6 × 1022 He/m2. The morphologies that developed after low-fluence bombardment weremore »different for each type of sample—MP SCW, MPEP SCW, MP PCW, and MPEP PCW. At the highest fluence, the SCW MPEP sample lost significantly more mass and developed a different morphology than the MP SCW sample. The PCW samples developed a similar morphology and had similar mass loss at the highest fluence. Surface preparation can have a significant effect on post-irradiation morphology that should be considered for the design of future fusion reactors such as ITER and DEMO.« less

  11. CPSC 505 Assignment 5 Solutions a) The direct irradiance on plane 1 is E0 cos . A fraction, , of E2, the total irradiance on

    E-Print Network [OSTI]

    Woodham, Robert J.

    CPSC 505 Assignment 5 Solutions a) The direct irradiance on plane 1 is E0 cos . A fraction, , of E2, the total irradiance on plane 2, is reflected. Exactly half of this contributes via inter-reflection to E1, the total irradiance on plane 1. Thus, E1 = E0 cos + 1/2 E2 Similarly, the direct irradiance on plane 2

  12. Solar spectral irradiance changes during cycle 24

    SciTech Connect (OSTI)

    Marchenko, S. V.; DeLand, M. T.

    2014-07-10

    We use solar spectra obtained by the Ozone Monitoring Instrument (OMI) on board the Aura satellite to detect and follow long-term (years) and short-term (weeks) changes in the solar spectral irradiance (SSI) in the 265-500 nm spectral range. During solar Cycle 24, in the relatively line-free regions the SSI changed by ?0.6% ± 0.2% around 265 nm. These changes gradually diminish to 0.15% ± 0.20% at 500 nm. All strong spectral lines and blends, with the notable exception of the upper Balmer lines, vary in unison with the solar 'continuum'. Besides the lines with strong chromospheric components, the most involved species include Fe I blends and all prominent CH, NH, and CN spectral bands. Following the general trend seen in the solar 'continuum', the variability of spectral lines also decreases toward longer wavelengths. The long-term solar cycle SSI changes are closely, to within the quoted 0.1%-0.2% uncertainties, matched by the appropriately adjusted short-term SSI variations derived from the 27 day rotational modulation cycles. This further strengthens and broadens the prevailing notion about the general scalability of the UV SSI variability to the emissivity changes in the Mg II 280 nm doublet on timescales from weeks to years. We also detect subtle deviations from this general rule: the prominent spectral lines and blends at ? ? 350 nm show slightly more pronounced 27 day SSI changes when compared to the long-term (years) trends. We merge the solar data from Cycle 21 with the current Cycle 24 OMI and GOME-2 observations and provide normalized SSI variations for the 170-795 nm spectral region.

  13. EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS (REVISION 1)

    SciTech Connect (OSTI)

    Clark, E.

    2013-09-13

    Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Revision 1 adds a comparison with results of a study of tritium exposed EPDM. The amount of gas produced by the gamma irradiation was found to be equivalent to about 280 days exposure to initially pure tritium gas at one atmosphere. The glass transition temperature of the tritium exposed EPDM rose about 10 ?C. over 280 days, while no glass transition temperature change was observed for gamma irradiated EPDM. This means that gamma irradiation in deuterium cannot be used as a surrogate for tritium exposure.

  14. AGR-2 IRRADIATION TEST FINAL AS-RUN REPORT

    SciTech Connect (OSTI)

    Blaise, Collin

    2014-07-01

    This document presents the as-run analysis of the AGR-2 irradiation experiment. AGR-2 is the second of the planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the U.S. Department of Energy as part of the Very High Temperature Reactor (VHTR) Technical Development Office (TDO) program. The objectives of the AGR-2 experiment are to: (a) Irradiate UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Fuel attributes are based on results obtained from the AGR-1 test and other project activities. (b) Provide irradiated fuel samples for post-irradiation experiment (PIE) and safety testing. (c) Support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. The primary objective of the test was to irradiate both UCO and UO2 TRISO (tri-structural isotropic) fuel produced from prototypic scale equipment to obtain normal operation and accident condition fuel performance data. The UCO compacts were subjected to a range of burnups and temperatures typical of anticipated prismatic reactor service conditions in three capsules. The test train also includes compacts containing UO2 particles produced independently by the United States, South Africa, and France in three separate capsules. The range of burnups and temperatures in these capsules were typical of anticipated pebble bed reactor service conditions. The results discussed in this report pertain only to U.S. produced fuel. In order to achieve the test objectives, the AGR-2 experiment was irradiated in the B-12 position of the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) for a total irradiation duration of 559.2 effective full power days (EFPD). Irradiation began on June 22, 2010, and ended on October 16, 2013, spanning 12 ATR power cycles and approximately three and a half calendar years. The test contained six independently controlled and monitored capsules. Each U.S. capsule contained 12 compacts of either UCO or UO2 AGR coated fuel. No fuel particles failed during the AGR-2 irradiation. Final burnup values on a per compact basis ranged from 7.26 to 13.15% FIMA (fissions per initial heavy-metal atom) for UCO fuel, and 9.01 to 10.69% FIMA for UO2 fuel, while fast fluence values ranged from 1.94 to 3.47´1025 n/m2 (E >0.18 MeV) for UCO fuel, and from 3.05 to 3.53´1025 n/m2 (E >0.18 MeV) for UO2 fuel. Time-average volume-average (TAVA) temperatures on a capsule basis at the end of irradiation ranged from 987°C in Capsule 6 to 1296°C in Capsule 2 for UCO, and from 996 to 1062°C in UO2-fueled Capsule 3. By the end of the irradiation, all of the installed thermocouples (TCs) had failed. Fission product release-to-birth (R/B) ratios were quite low. In the UCO capsules, R/B values during the first three cycles were below 10-6 with the exception of the hotter Capsule 2, in which the R/Bs reached 2´10-6. In the UO2 capsule (Capsule 3), the R/B values during the first three cycles were below 10-7. R/B values for all following cycles are not reliable due to gas flow and cross talk issues.

  15. Pinball Wizard at Full Tilt

    E-Print Network [OSTI]

    Vaughn, Alexa M

    2011-01-01

    of walls painted with bold, pop art close-ups of vintageartifacts of American art, science and pop-culture—there are

  16. BEAM TILTED CORRELATIONS Frank Vignola

    E-Print Network [OSTI]

    Oregon, University of

    from the modules, module temperature, ambient temperature, wind speed, incident solar radiation under standardized operation conditions (25 Celsius and 1000 watts/meter2 incident solar radiation and comprehensive solar radiation data. Specifically, these models were designed to use the National Solar Radiation

  17. Charge Collection Efficiency Simulations of Irradiated Silicon Strip Detectors

    E-Print Network [OSTI]

    T. Peltola

    2014-11-25

    During the scheduled high luminosity upgrade of LHC, the world's largest particle physics accelerator at CERN, the position sensitive silicon detectors installed in the vertex and tracking part of the CMS experiment will face more intense radiation environment than the present system was designed for. Thus, to upgrade the tracker to required performance level, comprehensive measurements and simulations studies have already been carried out. Essential information of the performance of an irradiated silicon detector is obtained by monitoring its charge collection efficiency (CCE). From the evolution of CCE with fluence, it is possible to directly observe the effect of the radiation induced defects to the ability of the detector to collect charge carriers generated by traversing minimum ionizing particles (mip). In this paper the numerically simulated CCE and CCE loss between the strips of irradiated silicon strip detectors are presented. The simulations based on Synopsys Sentaurus TCAD framework were performed before and after irradiation for fluences up to $1.5\\times10^{15}$ $\\textrm{n}_{\\textrm{eq}}$cm$^{-2}$ for the n-on-p sensors. A two level and non-uniform three level defect models were applied for the proton irradiation simulations and two level model for neutrons. The results are presented together with the measurements of strip detectors irradiated by different particles and fluences and show considerable agreement for both CCE and its position dependency.

  18. Irradiation-Accelerated Corrosion of Reactor Core Materials. Final Report

    SciTech Connect (OSTI)

    Jiao, Zhujie; Was, Gary; Bartels, David

    2015-04-02

    This project aims to understand how radiation accelerates corrosion of reactor core materials. The combination of high temperature, chemically aggressive coolants, a high radiation flux and mechanical stress poses a major challenge for the life extension of current light water reactors, as well as the success of most all GenIV concepts. Of these four drivers, the combination of radiation and corrosion places the most severe demands on materials, for which an understanding of the fundamental science is simply absent. Only a few experiments have been conducted to understand how corrosion occurs under irradiation, yet the limited data indicates that the effect is large; irradiation causes order of magnitude increases in corrosion rates. Without a firm understanding of the mechanisms by which radiation and corrosion interact in film formation, growth, breakdown and repair, the extension of the current LWR fleet beyond 60 years and the success of advanced nuclear energy systems are questionable. The proposed work will address the process of irradiation-accelerated corrosion that is important to all current and advanced reactor designs, but remains very poorly understood. An improved understanding of the role of irradiation in the corrosion process will provide the community with the tools to develop predictive models for in-reactor corrosion, and to address specific, important forms of corrosion such as irradiation assisted stress corrosion cracking.

  19. Light ion irradiation for unfavorable soft tissue sarcoma

    SciTech Connect (OSTI)

    Linstadt, D.; Castro, J.R.; Phillips, T.L.; Petti, P.L.; Collier, J.M.; Daftari, I.; Schoethaler, R.; Rayner, A.

    1990-09-01

    Between 1978 and 1989, 32 patients with unfavorable soft tissue sarcoma underwent light ion (helium, neon) irradiation with curative intent at Lawrence Berkeley Laboratory. The tumors were located in the trunk in 22 patients and head and neck in 10. Macroscopic tumor was present in 22 at the time of irradiation. Two patients had tumors apparently induced by previous therapeutic irradiation. Follow-up times for surviving patients ranged from 4 to 121 months (median 27 months). The overall 3-year actuarial local control rate was 62%; the corresponding survival rate was 50%. The 3-year actuarial control rate for patients irradiated with macroscopic tumors was 48%, while none of the patients with microscopic disease developed local recurrence (100%). The corresponding 3-year actuarial survival rates were 40% (macroscopic) and 78% (microscopic). Patients with retroperitoneal sarcoma did notably well; the local control rate and survival rate were 64% and 62%, respectively. Complications were acceptable; there were no radiation related deaths, while two patients (6%) required operations to correct significant radiation-related injuries. These results appear promising compared to those achieved by low -LET irradiation, and suggest that this technique merits further investigation.

  20. Irradiation-induced composition patterns in binary solid solutions

    SciTech Connect (OSTI)

    Dubey, Santosh; El-Azab, Anter [School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47906 (United States)] [School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47906 (United States)

    2013-09-28

    A theoretical/computational model for the irradiation-driven compositional instabilities in binary solid solutions has been developed. The model is suitable for investigating the behavior of structural alloys and metallic nuclear fuels in a reactor environment as well as the response of alloy thin films to ion beam irradiation. The model is based on a set of reaction-diffusion equations for the dynamics of vacancies, interstitials, and lattice atoms under irradiation. The dynamics of these species includes the stochastic generation of defects by collision cascades as well as the defect reactions and diffusion. The atomic fluxes in this model are derived based on the transitions of lattice defects. The set of reaction-diffusion equations are stiff, hence a stiffly stable method, also known as the Gear method, has been used to numerically approximate the equations. For the Cu-Au alloy in the solid solution regime, the model results demonstrate the formation of compositional patterns under high-temperature particle irradiation, with Fourier space properties (Fourier spectrum, average wavelength, and wavevector) depending on the cascade damage characteristics, average composition, and irradiation temperature.

  1. TEST RESULTS FROM GAMMA IRRADIATION OF ALUMINUM OXYHYDROXIDES

    SciTech Connect (OSTI)

    Fisher, D.; Westbrook, M.; Sindelar, R.

    2012-02-01

    Hydrated metal oxides or oxyhydroxides boehmite and gibbsite that can form on spent aluminum-clad nuclear fuel assemblies during in-core and post-discharge wet storage were exposed as granular powders to gamma irradiation in a {sup 60}Co irradiator in closed laboratory test vessels with air and with argon as separate cover gases. The results show that boehmite readily evolves hydrogen with exposure up to a dose of 1.8 x 10{sup 8} rad, the maximum tested, in both a full-dried and moist condition of the powder, whereas only a very small measurable quantity of hydrogen was generated from the granular powder of gibbsite. Specific information on the test setup, sample characteristics, sample preparation, irradiation, and gas analysis are described.

  2. AGR-1 Irradiation Test Final As-Run Report

    SciTech Connect (OSTI)

    Blaise P. Collin

    2012-06-01

    This document presents the as-run analysis of the AGR-1 irradiation experiment. AGR-1 is the first of eight planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the US Department of Energy (DOE) as part of the Next-Generation Nuclear Plant (NGNP) project. The objectives of the AGR-1 experiment are: 1. To gain experience with multi-capsule test train design, fabrication, and operation with the intent to reduce the probability of capsule or test train failure in subsequent irradiation tests. 2. To irradiate fuel produced in conjunction with the AGR fuel process development effort. 3. To provide data that will support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. In order to achieve the test objectives, the AGR-1 experiment was irradiated in the B-10 position of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) for a total duration of 620 effective full power days of irradiation. Irradiation began on December 24, 2006 and ended on November 6, 2009 spanning 13 ATR cycles and approximately three calendar years. The test contained six independently controlled and monitored capsules. Each capsule contained 12 compacts of a single type, or variant, of the AGR coated fuel. No fuel particles failed during the AGR-1 irradiation. Final burnup values on a per compact basis ranged from 11.5 to 19.6 %FIMA, while fast fluence values ranged from 2.21 to 4.39 ?1025 n/m2 (E >0.18 MeV). We’ll say something here about temperatures once thermal recalc is done. Thermocouples performed well, failing at a lower rate than expected. At the end of the irradiation, nine of the originally-planned 19 TCs were considered functional. Fission product release-to-birth (R/B) ratios were quite low. In most capsules, R/B values at the end of the irradiation were at or below 10-7 with only one capsule significantly exceeding this value. A maximum R/B of around 2?10-7 was reached at the end of the irradiation in Capsule 5. Several shakedown issues were encountered and resolved during the first three cycles. These include the repair of minor gas line leaks; repair of faulty gas line valves; the need to position moisture monitors in regions of low radiation fields for proper functioning; the enforcement of proper on-line data storage and backup, the need to monitor thermocouple performance, correcting for detector spectral gain shift, and a change in the mass flow rate range of the neon flow controllers.

  3. Neutron and gamma irradiation damage to organic materials.

    SciTech Connect (OSTI)

    White, Gregory Von, II; Bernstein, Robert

    2012-04-01

    This document discusses open literature reports which investigate the damage effects of neutron and gamma irradiation on polymers and/or epoxies - damage refers to reduced physical chemical, and electrical properties. Based on the literature, correlations are made for an SNL developed epoxy (Epon 828-1031/DDS) with an expected total fast-neutron fluence of {approx}10{sup 12} n/cm{sup 2} and a {gamma} dosage of {approx}500 Gy received over {approx}30 years at < 200 C. In short, there are no gamma and neutron irradiation concerns for Epon 828-1031/DDS. To enhance the fidelity of our hypotheses, in regards to radiation damage, we propose future work consisting of simultaneous thermal/irradiation (neutron and gamma) experiments that will help elucidate any damage concerns at these specified environmental conditions.

  4. Neutron radiography of irradiated nuclear fuel at Idaho National Laboratory

    SciTech Connect (OSTI)

    Craft, Aaron E.; Wachs, Daniel M.; Okuniewski, Maria A.; Chichester, David L.; Williams, Walter J.; Papaioannou, Glen C.; Smolinski, Andrew T.

    2015-09-10

    Neutron radiography of irradiated nuclear fuel provides more comprehensive information about the internal condition of irradiated nuclear fuel than any other non-destructive technique to date. Idaho National Laboratory (INL) has multiple nuclear fuels research and development programs that routinely evaluate irradiated fuels using neutron radiography. The Neutron Radiography reactor (NRAD) sits beneath a shielded hot cell facility where neutron radiography and other evaluation techniques are performed on these highly radioactive objects. The NRAD currently uses the foil-film transfer technique for imaging fuel that is time consuming but provides high spatial resolution. This study describes the NRAD and hot cell facilities, the current neutron radiography capabilities available at INL, planned upgrades to the neutron imaging systems, and new facilities being brought online at INL related to neutron imaging.

  5. Neutron radiography of irradiated nuclear fuel at Idaho National Laboratory

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

    Craft, Aaron E.; Wachs, Daniel M.; Okuniewski, Maria A.; Chichester, David L.; Williams, Walter J.; Papaioannou, Glen C.; Smolinski, Andrew T.

    2015-09-10

    Neutron radiography of irradiated nuclear fuel provides more comprehensive information about the internal condition of irradiated nuclear fuel than any other non-destructive technique to date. Idaho National Laboratory (INL) has multiple nuclear fuels research and development programs that routinely evaluate irradiated fuels using neutron radiography. The Neutron Radiography reactor (NRAD) sits beneath a shielded hot cell facility where neutron radiography and other evaluation techniques are performed on these highly radioactive objects. The NRAD currently uses the foil-film transfer technique for imaging fuel that is time consuming but provides high spatial resolution. This study describes the NRAD and hot cell facilities,more »the current neutron radiography capabilities available at INL, planned upgrades to the neutron imaging systems, and new facilities being brought online at INL related to neutron imaging.« less

  6. Irradiated Microsphere Gamma Analyzer for Examination of Particle Fuel

    SciTech Connect (OSTI)

    Paul A. Demkowicz; Various

    2014-06-01

    Fabrication of the first series of fuel compacts for the current US tristructural isotropic (TRISO) coated particle fuel development and qualification effort was completed at Oak Ridge National Laboratory (ORNL) in 2006. In November of 2009, after almost 3 years and 620 effective full power days of irradiation in the Advanced Test Reactor at Idaho National Laboratory (INL), the first Advanced Gas Reactor irradiation test (AGR-1) was concluded. Compacts were irradiated at a calculated timeaveraged, volume-averaged temperature of 955–1136°C to a burnup ranging from 11.2–19.5% fissions per initial metal atom and a total fast fluence of 2.2–4.3·1025 n/m2 [1]. No indication of fission product release from TRISO coating failure was observed during the irradiation test, based on real-time monitoring of gaseous fission products. Post-irradiation examination (PIE) and hightemperature safety testing of the compacts has been in progress at both ORNL and INL since 2010, and have revealed small releases of a limited subset of fission products (such as silver, cesium, and europium). Past experience has shown that some elements can be released from TRISO particles when a defect forms in the SiC layer, even when one or more pyrocarbon layers remain intact and retain the gaseous fission products. Some volatile elements can also be released by diffusion through an intact SiC layer during safety testing if temperatures are high enough and the duration is long enough. In order to understand and quantify the release of certain radioactive fission products, it is sometimes necessary to individually examine each of the more than 4000 coated particles in a given compact. The Advanced Irradiated Microsphere Gamma Analyzer (Advanced- IMGA) was designed to perform this task in a remote hot cell environment. This paper describes the Advanced- IMGA equipment and examination process and gives results for a typical full compact evaluation.

  7. Thermal response of photovoltaic cell to laser beam irradiation

    E-Print Network [OSTI]

    Yuan, Yu-Chen

    2014-01-01

    This paper firstly presents the concept of using dual laser beam to irradiate the photovoltaic cell, so as to investigate the temperature dependency of the efficiency of long distance energy transmission. Next, the model on the multiple reflection and absorption of any monochromatic light in multilayer structure has been established, and the heat generation in photovoltaic cell has been interpreted in this work. Then, the finite element model has been set up to calculate the temperature of photovoltaic cell subjected to laser irradiation. Finally, the effect of temperature elevation on the efficiency and reliability of photovoltaic cell has been discussed to provide theoretical references for designing the light-electricity conversion system.

  8. Computation of glint, glare, and solar irradiance distribution

    DOE Patents [OSTI]

    Ho, Clifford Kuofei; Khalsa, Siri Sahib Singh

    2015-08-11

    Described herein are technologies pertaining to computing the solar irradiance distribution on a surface of a receiver in a concentrating solar power system or glint/glare emitted from a reflective entity. At least one camera captures images of the Sun and the entity of interest, wherein the images have pluralities of pixels having respective pluralities of intensity values. Based upon the intensity values of the pixels in the respective images, the solar irradiance distribution on the surface of the entity or glint/glare corresponding to the entity is computed.

  9. Fission product release from irradiated LWR fuel under accident conditions

    SciTech Connect (OSTI)

    Strain, R.V.; Sanecki, J.E.; Osborne, M.F.

    1984-01-01

    Fission product release from irradiated LWR fuel is being studied by heating fuel rod segments in flowing steam and an inert carrier gas to simulate accident conditions. Fuels with a range of irradiation histories are being subjected to several steam flow rates over a wide range of temperatures. Fission product release during each test is measured by gamma spectroscopy and by detailed examination of the collection apparatus after the test has been completed. These release results are complemented by a detailed posttest examination of samples of the fuel rod segment. Results of release measurements and fuel rod characterizations for tests at 1400 through 2000/sup 0/C are presented in this paper.

  10. SLIGHTLY IRRADIATED FUEL (SIF) INTERIM DISPOSITION PROJECT

    SciTech Connect (OSTI)

    NORTON SH

    2010-02-23

    CH2M HILL Plateau Remediation Company (CH2M HILL PRC) is proud to submit the Slightly Irradiated Fuel (SIF) Interim Disposition Project for consideration by the Project Management Institute as Project of the Year for 2010. The SIF Project was a set of six interrelated sub-projects that delivered unique stand-alone outcomes, which, when integrated, provided a comprehensive and compliant system for storing high risk special nuclear materials. The scope of the six sub-projects included the design, construction, testing, and turnover of the facilities and equipment, which would provide safe, secure, and compliant Special Nuclear Material (SNM) storage capabilities for the SIF material. The project encompassed a broad range of activities, including the following: Five buildings/structures removed, relocated, or built; Two buildings renovated; Structural barriers, fencing, and heavy gates installed; New roadways and parking lots built; Multiple detection and assessment systems installed; New and expanded communication systems developed; Multimedia recording devices added; and A new control room to monitor all materials and systems built. Project challenges were numerous and included the following: An aggressive 17-month schedule to support the high-profile Plutonium Finishing Plant (PFP) decommissioning; Company/contractor changeovers that affected each and every project team member; Project requirements that continually evolved during design and construction due to the performance- and outcome-based nature ofthe security objectives; and Restrictions imposed on all communications due to the sensitive nature of the projects In spite of the significant challenges, the project was delivered on schedule and $2 million under budget, which became a special source of pride that bonded the team. For years, the SIF had been stored at the central Hanford PFP. Because of the weapons-grade piutonium produced and stored there, the PFP had some of the tightest security on the Hanford nuclear reservation. Workers had to pass through metal detectors when they arrived at the plant and materials leaving the plant had to be scanned for security reasons. Whereas other high-security nuclear materials were shipped from the PFP to Savannah River, S.C. as part ofa Department of Energy (DOE) program to consolidate weapons-grade plutonium, it was determined that the SIF should remain onsite pending disposition to a national repository. Nevertheless, the SIF still requires a high level of security that the PFP complex has always provided. With the 60-year PFP mission of producing and storing plutonium concluded, the environmental cleanup plans for Hanford call for the demolition of the 63-building PFP complex. Consequently, if the SIF remained at PFP it not only would have interfered with the environmental cleanup plans, but would have required $100 million in facility upgrades to meet increased national security requirements imposed after the 9/11 terrorist attacks. A new smaller and more cost-effective area was needed to store this material, which led to the SIF Project. Once the SIF project was successfully completed and the SIF was safely removed from PFP, the existing Protected Area at PFP could be removed, and demolition could proceed more quickly without being encumbered by restrictive security requirements that an active Protected Area requires. The lightened PFP security level brought by safely removing and storing the SIF would also yield lowered costs for deactivation and demolition, as well as reduce overall life-cycle costs.

  11. The response of fatty acids and pigments to variations in temperature and irradiance in the Marine Diatom Thalassiosira pseudonana :

    E-Print Network [OSTI]

    Shang, Frank F.

    2011-01-01

    in Temperature and Irradiance on the Diatom ThalassiosiraSizes of the 18 ? C, at 3 irradiance levels 80, 240 and 420Srezepek. Influence of irradiance and temperature on the

  12. A new generation of satellite based solar irradiance calculation schemes R. W. Mueller, D. Heinemann, C. Hoyer & R. Kuhlemann

    E-Print Network [OSTI]

    Heinemann, Detlev

    A new generation of satellite based solar irradiance calculation schemes R. W. Mueller, D. Piernavieja Instituto Tecnologico de Canarias, Spain Keywords: radiative transfer, solar irradiance, MSG irradiance calculation scheme, including the functional treatment of the diurnal variation of the solar

  13. Bright x-ray sources from laser irradiation of foams with high...

    Office of Scientific and Technical Information (OSTI)

    Bright x-ray sources from laser irradiation of foams with high concentration of Ti Citation Details In-Document Search Title: Bright x-ray sources from laser irradiation of foams...

  14. Conjugated linoleic acid reduces lipid oxidation in irradiated, cooked ground beef patties 

    E-Print Network [OSTI]

    Chae, Sung Hee

    2007-09-17

    This study was conducted to examine the antioxidative effect of conjugated linoleic acid (CLA) in irradiated, cooked ground beef patties. The hypothesis was that CLA would be retained during irradiation and would reduce lipid oxidation...

  15. Gamma Irradiation of sLHC Prototype Silicon Strip Detectors and Test Structures of the SMART

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Gamma Irradiation of sLHC Prototype Silicon Strip Detectors and Test Structures of the SMART funded SMART project. They were irradiated with 60 Co to test total dose (TID) effects, in order to study

  16. Detection of toxic factors after gamma-irradiation in vitro and in vivo 

    E-Print Network [OSTI]

    Shihabi, Zakariya Kamel

    1965-01-01

    from H202. If catalase was added during the irradiation period, the degradation of the glucose can be avoided. This observation may have practical application to prevent, or to reduce the side effects (38) seen in sterilised foods by irradiation...

  17. Electron Irradiation Induced Changes of the Electrical Transport Properties of Graphene 

    E-Print Network [OSTI]

    Woo, Sung Oh

    2014-08-06

    This research investigates the effect of electron irradiation on transport properties in graphene Field Effect Transistor (FET) devices. Upon irradiation, graphene is doped with electrons and adsorbs molecules by transfer of accumulated electrons...

  18. POST-IRRADIATION PROPERTIES OF CANDIDATE MATERIALS FOR HIGH-POWER TARGETS

    E-Print Network [OSTI]

    McDonald, Kirk

    capacity, and the fracture toughness of these materials. THE IRRADIATED MATERIALS Carbon-carbon composite). We will even- tually examine the effect of irradiation on the CTE, ductil- ity, yield strength, heat

  19. Pressure-sensitive blackbody point radiation induced by infrared diode laser irradiation

    E-Print Network [OSTI]

    Cao, Wenwu

    Pressure-sensitive blackbody point radiation induced by infrared diode laser irradiation Feng Qin,1, by irradiation of well-matched infrared (IR) lasers upon the Yb3þ ions, ultrabroadband luminescence can

  20. Response of nanostructured ferritic alloys to high-dose heavy ion irradiation

    SciTech Connect (OSTI)

    Parish, Chad M.; White, Ryan M.; LeBeau, James M.; Miller, Michael K.

    2014-02-01

    A latest-generation aberration-corrected scanning/transmission electron microscope (STEM) is used to study heavy-ion-irradiated nanostructured ferritic alloys (NFAs). Results are presented for STEM X-ray mapping of NFA 14YWT irradiated with 10 MeV Pt to 16 or 160 dpa at -100°C and 750°C, as well as pre-irradiation reference material. Irradiation at -100°C results in ballistic destruction of the beneficial microstructural features present in the pre-irradiated reference material, such as Ti-Y-O nanoclusters (NCs) and grain boundary (GB) segregation. Irradiation at 750°C retains these beneficial features, but indicates some coarsening of the NCs, diffusion of Al to the NCs, and a reduction of the Cr-W GB segregation (or solute excess) content. Ion irradiation combined with the latest-generation STEM hardware allows for rapid screening of fusion candidate materials and improved understanding of irradiation-induced microstructural changes in NFAs.

  1. Irradiation effects in carbon nanotubes A.V. Krasheninnikov *, K. Nordlund

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    : Carbon nanotubes; Ion irradiation; Electron irradiation; Defect annealing 1. Introduction Carbon are estimated bo be, respectively, about 19 and 56 times that of steel [2]. Depending on the way of how

  2. RIS-M-2352 DETERMINATION OF RETAINED GAS IN IRRADIATED FUEL SAMPLES

    E-Print Network [OSTI]

    -IRRADIATION EXAMINATION; RADIATION CHEMISTRY; SPENT FUELS; URANIUM DIOXIDE; XENON; XENON ISOTOPES UDC 621.039.548 ISBN 87

  3. Impact of 15 Jan 2010 annular solar eclipse on the equatorial and low latitude ionosphere over Indian region from Magnetometer, Ionosonde and GPS observations

    E-Print Network [OSTI]

    Panda, Sampad Kumar; Rajaram, Girija; Sripathi, Samireddipalle; Bhaskar, Ankush

    2015-01-01

    The annular eclipse of Jan 15, 2010 over southern India was studied with a network of multi-instrumental observations consisting magnetometer, ionosonde and GPS receivers. By selecting the day before and the normal EEJ days as the control days, it is intrinsically proved that the regular eastward electric field for the whole day at the equator was not just weakened but actually was flipped for several hours by the influence of tides related to the spectacular Sun-Moon-Earth alignment near the middle of the day. The effect of flipping the electric field was clearly seen in the equatorial ionosonde data and through the large array of GPS receivers that accomplished the TEC data. The main impact of the change in the electric field was the reduced EIA at all latitudes, with the anomaly crest that shifted towards the equator. The equatorial F-region density profile was also showing an enhanced F region peak in spite of a reduced VTEC. By comparison to the plasma density depletion associated with the temporary lack...

  4. Total solar irradiance variation during rapid sunspot H. Jabran Zahid

    E-Print Network [OSTI]

    Hudson, Hugh

    solar irradiance (TSI), a phenomenon associated with the local suppression of convective energy of convective energy transport near the solar sur- face involves such efficient transport of energy to gravitational potential energy, and the conversion of some of this energy to heat via flows would cause local

  5. Post Irradiation Capabilities at the Idaho National Laboratory

    SciTech Connect (OSTI)

    Schulthess, J.L.; Robert D. Mariani; Rory Kennedy; Doug Toomer

    2011-08-01

    The U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) oversees the research, development, and demonstration activities that ensure nuclear energy remains a viable energy option for the United States. Fuel and material development through fabrication, irradiation, and characterization play a significant role in accomplishing the research needed to support nuclear energy. All fuel and material development requires the understanding of irradiation effects on the fuel performance and relies on irradiation experiments ranging from tests aimed at targeted scientific questions to integral effects under representative and prototypic conditions. The DOE recently emphasized a solution-driven, goal-oriented, science-based approach to nuclear energy development. Nuclear power systems and materials were initially developed during the latter half of the 20th century and greatly facilitated by the United States’ ability and willingness to conduct large-scale experiments. Fifty-two research and test reactors with associated facilities for performing fabrication and pre and post irradiation examinations were constructed at what is now Idaho National Laboratory (INL), another 14 at Oak Ridge National Laboratory (ORNL), and a few more at other national laboratory sites. Building on the scientific advances of the last several decades, our understanding of fundamental nuclear science, improvements in computational platforms, and other tools now enable technological advancements with less reliance on large-scale experimentation.

  6. Post Irradiation Capabilities at the Idaho National Laboratory

    SciTech Connect (OSTI)

    Schulthess, J.L.

    2011-08-01

    The U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) oversees the research, development, and demonstration activities that ensure nuclear energy remains a viable energy option for the United States. Fuel and material development through fabrication, irradiation, and characterization play a significant role in accomplishing the research needed to support nuclear energy. All fuel and material development requires the understanding of irradiation effects on the fuel performance and relies on irradiation experiments ranging from tests aimed at targeted scientific questions to integral effects under representative and prototypic conditions. The DOE recently emphasized a solution-driven, goal-oriented, science-based approach to nuclear energy development. Nuclear power systems and materials were initially developed during the latter half of the 20th century and greatly facilitated by the United States ability and willingness to conduct large-scale experiments. Fifty-two research and test reactors with associated facilities for performing fabrication and pre and post irradiation examinations were constructed at what is now Idaho National Laboratory (INL), another 14 at Oak Ridge National Laboratory (ORNL), and a few more at other national laboratory sites. Building on the scientific advances of the last several decades, our understanding of fundamental nuclear science, improvements in computational platforms, and other tools now enable technological advancements with less reliance on large-scale experimentation.

  7. EBeam Irradiation for Water Reuse: Removal of Bromate 

    E-Print Network [OSTI]

    Wang, Li

    2015-07-28

    Beam) irradiation has been investigated in areas including both bacterial/viral disinfection and chemical contaminant removal. However, eBeam research on BrO3- removal is limited. Particularly, the application of eBeam to water reuse has not been investigated...

  8. Thermoelastic Generation of Ultrasound by Line-Focused Laser Irradiation

    E-Print Network [OSTI]

    Huerta, Antonio

    Thermoelastic Generation of Ultrasound by Line-Focused Laser Irradiation Irene Arias and Jan D 60208, USA Abstract A two-dimensional theoretical model for the field generated in the thermoelas- tic for the model. Some representative results are presented to illustrate the generated field and provide insight

  9. Fusion Technology at CIEMAT Overview of Material Irradiation Activities

    E-Print Network [OSTI]

    McDonald, Kirk

    Fusion Technology at CIEMAT Overview of Material Irradiation Activities A. Ibarra RaDIATE Collaboration Meeting . May 19, 2014 #12;RaDIATE Collaboration Meeting . May 19, 2014 CIEMAT CIEMAT is a public people and yearly budget around 100 M. CIEMAT activities are organized in 5 technical departments

  10. Spectral solar irradiance before and during a Harmattan dust spell

    SciTech Connect (OSTI)

    Adeyefa, Z.D. [Federal Univ. of Technology, Akure (Nigeria)] [Federal Univ. of Technology, Akure (Nigeria); Holmgren, B. [Uppsala Univ. (Sweden)] [Uppsala Univ. (Sweden)

    1996-09-01

    Measurements of the ground-level spectral distributions of the direct, diffuse and global solar irradiance between 300 and 1100 nm were made at Akure (7.15{degree}N, 5.5{degree}E), Nigeria, in December 1991 before and during a Harmattan dust spell employing a spectroradiometer (LICOR LI-1800) with 6 nm resolution. The direct spectral solar irradiance which was initially reduced before the dust storm was further attenuated by about 50% after the spell. Estimated values of the Angstrom turbidity coefficient {beta} indicated an increase of about 146% of this parameter while the Angstrom wavelength-exponent {alpha} decreased by about 65% within the 2-day study period. The spectral diffuse-to-direct and diffuse-to-global ratios suggest that the main cause of the significant reduction in solar irradiance at the surface was the scattering by the aerosol which led to an increase in the diffuse component. The global irradiance though reduced, was less sensitive to changing Harmattan conditions. It is recommended that solar energy devices that use radiation from Sun and sky be used under fluctuating Harmattan conditions. There are some deviations from the Angstrom formula under very turbid Harmattan conditions which could be explained by the relative increase of the particle sizes. 31 refs., 12 figs., 3 tabs.

  11. MATERIAL IRRADIATION STUDIES HIGH-INTENSITY PROTON BEAM TARGETS

    E-Print Network [OSTI]

    McDonald, Kirk

    loss Strength loss/gain Fracture toughness Physical property changes CTE Diffusivity Heat capacityBeMet Nickel-Plated Aluminum Material Matrix TESTS (on-going + upcoming) Mechanical property changes Ductility (C) Strain(%) Gum (unirradiated) Gum (irradiated) GUM Metal Strengthens but clearly looses the "super-ductility

  12. SURVEILLANCE OF PHOTOVOLTAIC SOLAR ENERGY SYSTEMS USING METEOSAT DERIVED IRRADIANCES

    E-Print Network [OSTI]

    Heinemann, Detlev

    be related to a bad performance of numerous PV systems: the overall energy production 1 #12;(and thus. Regarding the increasing pay-back rates for PV energy (0.99 DM/kWh in Germany from spring 2000 onwardsSURVEILLANCE OF PHOTOVOLTAIC SOLAR ENERGY SYSTEMS USING METEOSAT DERIVED IRRADIANCES Annette Hammer

  13. UV Irradiation of Polycyclic Aromatic Hydrocarbons in Ices

    E-Print Network [OSTI]

    UV Irradiation of Polycyclic Aromatic Hydrocarbons in Ices: Production of Alcohols, Quinones. Clemett,3 Richard N. Zare3 Polycyclic aromatic hydrocarbons (PAHs) in water ice were exposed to ultra, and ethers, and reduced, producing partially hydrogenated aromatic hydrocarbons, molecules that account

  14. Heavy Oil Upgrading from Electron Beam (E-Beam) Irradiation 

    E-Print Network [OSTI]

    Yang, Daegil

    2011-02-22

    to upgrade. This thesis demonstrates that electron beam (E-Beam) heavy oil upgrading, which uses unique features of E-Beam irradiation, may be used to improve conventional heavy oil upgrading. E-Beam processing lowers the thermal energy requirements and could...

  15. Irradiation performance of AGR-1 high temperature reactor fuel

    SciTech Connect (OSTI)

    Paul A. Demkowicz; John D. Hunn; Robert N. Morris; Charles A. Baldwin; Philip L. Winston; Jason M. Harp; Scott A. Ploger; Tyler Gerczak; Isabella J. van Rooyen; Fred C. Montgomery; Chinthaka M. Silva

    2014-10-01

    The AGR-1 experiment contained 72 low-enriched uranium oxide/uranium carbide TRISO-coated particle fuel compacts in six capsules irradiated to burnups of 11.2 to 19.5% FIMA, with zero TRISO coating failures detected during the irradiation. The irradiation performance of the fuel–including the extent of fission product release and the evolution of kernel and coating microstructures–was evaluated based on detailed examination of the irradiation capsules, the fuel compacts, and individual particles. Fractional release of 110mAg from the fuel compacts was often significant, with capsule-average values ranging from 0.01 to 0.38. Analysis of silver release from individual compacts indicated that it was primarily dependent on fuel temperature history. Europium and strontium were released in small amounts through intact coatings, but were found to be significantly retained in the outer pyrocrabon and compact matrix. The capsule-average fractional release from the compacts was 1×10 4 to 5×10 4 for 154Eu and 8×10 7 to 3×10 5 for 90Sr. The average 134Cs release from compacts was <3×10 6 when all particles maintained intact SiC. An estimated four particles out of 2.98×105 experienced partial cesium release due to SiC failure during the irradiation, driving 134Cs release in two capsules to approximately 10 5. Identification and characterization of these particles has provided unprecedented insight into the nature and causes of SiC coating failure in high-quality TRISO fuel. In general, changes in coating morphology were found to be dominated by the behavior of the buffer and inner pyrolytic carbon (IPyC), and infrequently observed SiC layer damage was usually related to cracks in the IPyC. Palladium attack of the SiC layer was relatively minor, except for the particles that released cesium during irradiation, where SiC corrosion was found adjacent to IPyC cracks. Palladium, silver, and uranium were found in the SiC layer of irradiated particles, and characterization of these elements within the SiC microstructure is the subject of ongoing focused study.

  16. Irradiation effect on deuterium behaviour in low-dose HFIR neutron-irradiated tungsten

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

    Shimada, Masashi; Cao, G.; Otsuka, T.; Hara, M.; Kobayashi, M.; Oya, Y.; Hatano, Y.

    2015-01-01

    Tungsten samples were irradiated by neutrons in the High Flux Isotope Reactor (HFIR), Oak Ridge National Laboratory at reactor coolant temperatures of 50–70 ?C to low displacement damage of 0.025 and 0.3 dpa. After cooling down, the HFIR neutronirradiated tungsten samples were exposed to deuterium plasmas in the Tritium Plasma Experiment, Idaho National Laboratory at 100, 200 and 500 ?C twice at the ion fluence of 5×1025 m-2 to reach the total ion fluence of 1×1026 m-2 in order to investigate maximum near-surface (more »in 0.3 dpa samples. The large discrepancy between the total retention via thermal desorption spectroscopy and the nearsurface retention via nuclear reaction analysis indicated the deuterium was trapped in bulk (at least 50µm depth for 0.025 dpa and 35µm depth for 0.3 dpa) at 500 ?C cases even in the relatively low ion fluence of 1026 m-2.« less

  17. Irradiation effect on deuterium behaviour in low-dose HFIR neutron-irradiated tungsten

    SciTech Connect (OSTI)

    Shimada, Masashi [Idaho National Lab. (INL), Idaho Falls, ID (United States).Fusion Safety Program; Cao, G. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Engineering Physics; Otsuka, T. [Kyushu Univ., Fukuoka (Japan). Interdisciplinary Graduate School of Engineering Science; Hara, M. [Univ. of Toyama (Japan). Hydrogen Isotope Center; Kobayashi, M. [Shizuoka Univ. (Japan). Radioscience Research Lab.; Oya, Y. [Shizuoka Univ. (Japan). Radioscience Research Lab.; Hatano, Y. [Shizuoka Univ. (Japan). Radioscience Research Lab.

    2015-01-01

    Tungsten samples were irradiated by neutrons in the High Flux Isotope Reactor (HFIR), Oak Ridge National Laboratory at reactor coolant temperatures of 50–70 ?C to low displacement damage of 0.025 and 0.3 dpa. After cooling down, the HFIR neutronirradiated tungsten samples were exposed to deuterium plasmas in the Tritium Plasma Experiment, Idaho National Laboratory at 100, 200 and 500 ?C twice at the ion fluence of 5×1025 m-2 to reach the total ion fluence of 1×1026 m-2 in order to investigate maximum near-surface (<5µm depth) deuterium concentration increased from 0.5 at% D/W in 0.025 dpa samples to 0.8 at% D/W in 0.3 dpa samples. The large discrepancy between the total retention via thermal desorption spectroscopy and the nearsurface retention via nuclear reaction analysis indicated the deuterium was trapped in bulk (at least 50µm depth for 0.025 dpa and 35µm depth for 0.3 dpa) at 500 ?C cases even in the relatively low ion fluence of 1026 m-2.

  18. Irradiance Environment Maps In the introduction to this dissertation, we noted that complex realistic lighting environ-

    E-Print Network [OSTI]

    Stanford University

    Chapter 4 Irradiance Environment Maps In the introduction to this dissertation, we noted. This chapter considers the case of Irradiance Environment Maps, correspond- ing to the reflection from diffuse. Using an analytic expression for the irradiance in terms of spherical harmonic coefficients

  19. IRRADIATION DAMAGE STUDIES OF HIGH POWER ACCELERATOR MATERIALS Nicholas Simos1

    E-Print Network [OSTI]

    McDonald, Kirk

    IWSMT8 IRRADIATION DAMAGE STUDIES OF HIGH POWER ACCELERATOR MATERIALS Nicholas Simos1 , H.G. Kirk@bnl.gov, telephone: 631-344-7229, fax: 631 344-7650) #12;IWSMT8 IRRADIATION DAMAGE STUDIES OF HIGH-POWER ACCELERATOR which leads to accumulated irradiation damage, also endure short exposure that manifests itself

  20. Ecological Modelling 143 (2001) 227243 A globally applicable model of daily solar irradiance

    E-Print Network [OSTI]

    Hunt Jr., E. Raymond

    2001-01-01

    Ecological Modelling 143 (2001) 227­243 A globally applicable model of daily solar irradiance at many ground stations, the total daily solar irradiance (Rs) received at the earth's surface to measured solar irradiance. In a global comparison for the year 1987, VP-RAD-estimated and satellite

  1. Irradiance Environment Maps In the introduction to this dissertation, we noted that complex realistic lighting environ

    E-Print Network [OSTI]

    Stanford University

    Chapter 4 Irradiance Environment Maps In the introduction to this dissertation, we noted. This chapter considers the case of Irradiance Environment Maps, correspond­ ing to the reflection from diffuse. Using an analytic expression for the irradiance in terms of spherical harmonic coefficients

  2. ClosedForm Expressions for Irradiance from NonUniform Lambertian

    E-Print Network [OSTI]

    Closed­Form Expressions for Irradiance from Non­Uniform Lambertian Luminaires Part I : Linearly Institute of Technology Pasadena, California June 15, 2000 #12; #12; Closed­Form Expressions for Irradiance Arvo # Abstract We present a closed­form expression for the irradiance at a point on a surface due

  3. VertexBased Formulations of Irradiance from Polygonal Sources Technical Report UUCS00012

    E-Print Network [OSTI]

    Vertex­Based Formulations of Irradiance from Polygonal Sources Technical Report UUCS­00­012 Michael M. Stark Department of Computer Science University of Utah May 29, 2000 Abstract Irradiance]. Radiance is measured in units of W/m 2 /sr. A related quantity is irradiance, the incident radiant flux

  4. Fast and accurate estimation of solar irradiance on Martian slopes Aymeric Spiga1

    E-Print Network [OSTI]

    Spiga, Aymeric

    Fast and accurate estimation of solar irradiance on Martian slopes Aymeric Spiga1 and Franc parameterization is proposed in this study to calculate, in a Mars-like dusty atmosphere, the solar irradiance better than 5 W.mÀ2 . Such a fast and accurate method to calculate solar irradiance on Martian slopes

  5. The Impact of Irradiance Time Behaviors on Inverter Sizing and Design

    E-Print Network [OSTI]

    Lehman, Brad

    The Impact of Irradiance Time Behaviors on Inverter Sizing and Design Song Chen Peng Li David Brady, Massachusetts chen.son@husky.neu.edu Abstract--This paper investigates the time behavior of over- irradiance of inverters is also proposed. Keywords ­ Inverter sizing, short-interval irradiance data, inverter protection

  6. Irradiation and Potassium Sorbate Compared as Preservation Treatments for Atlantic Cod, Gadus morhua

    E-Print Network [OSTI]

    Irradiation and Potassium Sorbate Compared as Preservation Treatments for Atlantic Cod, Gadus of these two seafood preserva- tion methods (irradiation vs. sorbate ABSTRACT-Treatments offresh Atlantic cod, Gadus morhua, fillets with either 100 Krad gamma irradiation or a sorbate dip were found

  7. An Efficient Representation for Irradiance Environment Maps Ravi Ramamoorthi Pat Hanrahan

    E-Print Network [OSTI]

    Stanford University

    An Efficient Representation for Irradiance Environment Maps Ravi Ramamoorthi Pat Hanrahan Stanford by an environment map. Using an analytic expres­ sion for the irradiance in terms of spherical harmonic coefficients­frequency modes of the illumination, in order to achieve average errors of only 1%. In other words, the irradiance

  8. Diffuse attenuation coefficient of downwelling irradiance: An evaluation of remote sensing methods

    E-Print Network [OSTI]

    Lee, Zhongping

    Diffuse attenuation coefficient of downwelling irradiance: An evaluation of remote sensing methods February 2005. [1] The propagation of downwelling irradiance at wavelength l from surface to a depth (z in situ measurements of the vertical profiles of downwelling irradiance. The comparisons show that the two

  9. Total Solar Irradiance Calibration Transfer Experiment/TIM Frequently Asked Questions

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    TCTE Total Solar Irradiance Calibration Transfer Experiment/TIM Frequently Asked Questions What is the purpose of the TCTE mission? The Total Solar Irradiance Calibration Transfer Experiment (TCTE to monitor changes in solar irradiance at the top of the Earth's atmosphere. TCTE will launch as one of five

  10. THE USE OF MSG DATA WITHIN A NEW TYPE OF SOLAR IRRADIANCE CALCULATION SCHEME

    E-Print Network [OSTI]

    Heinemann, Detlev

    THE USE OF MSG DATA WITHIN A NEW TYPE OF SOLAR IRRADIANCE CALCULATION SCHEME R. W. Mueller , H). Within this paper, the new type of the solar irradiance calculation scheme, including the functional treatment of the diurnal variation of the solar irradiance, is described. 1 INTRODUCTION Remote Sensing from

  11. Climate sensitivity of the Earth to solar irradiance David H. Douglass

    E-Print Network [OSTI]

    Douglass, David H.

    Climate sensitivity of the Earth to solar irradiance David H. Douglass Department of Physics. A weaker effect, which must exist, is solar irradiance. We have determined the solar effect on the temperature from satellites measurements (available since 1979) of the solar irradiance and the temperature

  12. Irradiation-induced stiffening of carbon nanotube bundles M. Sammalkorpi a,*,1

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Irradiation-induced stiffening of carbon nanotube bundles M. Sammalkorpi a,*,1 , A irradiation of bundles of single-walled carbon nanotubes resulted in dramatic increase of the bundle bending modulus at moderate irradiation doses, followed by a decrease in mechanical properties at higher doses

  13. Irradiation of Dye-Doped Microspheres with a Strongly Focused Laser Beam

    E-Print Network [OSTI]

    Zare, Richard N.

    Irradiation of Dye-Doped Microspheres with a Strongly Focused Laser Beam Results in Alignment upon Received December 12, 2001 ABSTRACT The irradiation of dye-doped polystyrene microspheres with an argon ion trap (985 nm). This behavior is well described by a model in which the differently irradiated portions

  14. Ion Irradiation Effects in Synthetic Garnets Incorporating Actinides Satoshi Utsunomiya1

    E-Print Network [OSTI]

    Utsunomiya, Satoshi

    Ion Irradiation Effects in Synthetic Garnets Incorporating Actinides Satoshi Utsunomiya1 , Lu.0 MeV Kr2+ irradiation with in situ transmission electron microscopy over the temperature range of 50 the long term radiation effects due to radioactive decay can be simulated in short term with heavy ion-irradiation

  15. Short-term irradiance variability: Preliminary estimation of station pair correlation as a function of distance

    E-Print Network [OSTI]

    Review Short-term irradiance variability: Preliminary estimation of station pair correlation the irradiance variability observed at two neighboring sites as a function of their distance of the considered time scale. Ó 2012 Elsevier Ltd. All rights reserved. Keywords: Irradiance; Variability; High

  16. An Efficient Representation for Irradiance Environment Maps Ravi Ramamoorthi Pat Hanrahan

    E-Print Network [OSTI]

    Columbia University

    An Efficient Representation for Irradiance Environment Maps Ravi Ramamoorthi Pat Hanrahan Stanford by an environment map. Using an analytic expres- sion for the irradiance in terms of spherical harmonic coefficients-frequency modes of the illumination, in order to achieve average errors of only 1%. In other words, the irradiance

  17. Ion irradiation-induced amorphization and nano-crystal formation in garnets

    E-Print Network [OSTI]

    Utsunomiya, Satoshi

    Ion irradiation-induced amorphization and nano-crystal formation in garnets S. Utsunomiya a , L been examined by 1.0 MeV Kr2þ irradiation with in situ transmission electron microscopy over ion irradiation of the G3 garnet at a temperature of 1023 K near the Tc, nano-crystals were produced

  18. SPECTRAL DISTRIBUTIONS OF DIFFUSE AND GLOBAL IRRADIANCE FOR CLEAR AND CLOUDY PERIODS

    E-Print Network [OSTI]

    Oregon, University of

    SPECTRAL DISTRIBUTIONS OF DIFFUSE AND GLOBAL IRRADIANCE FOR CLEAR AND CLOUDY PERIODS Gina@uoregon.edu ABSTRACT An LI1800 Portable Spectroradiometer is used to measure solar spectral irradiance for solar showing global horizontal and diffuse irradiance for clear and cloudy days, and then used

  19. P5.60B DERIVATION OF DAYLIGHT AND SOLAR IRRADIANCE DATA FROM SATELLITE OBSERVATIONS

    E-Print Network [OSTI]

    Heinemann, Detlev

    P5.60B DERIVATION OF DAYLIGHT AND SOLAR IRRADIANCE DATA FROM SATELLITE OBSERVATIONS A. Hammer, D of the downward surface shortwave irradiance from satellite observations has been subject to numerous project SATELLIGHT an attempt is made to use satellite methods to derive daylight and solar irradiance

  20. Irradiation-induced disordering and amorphization of Al3Ti-based intermetallic compounds

    E-Print Network [OSTI]

    Motta, Arthur T.

    Irradiation-induced disordering and amorphization of Al3Ti-based intermetallic compounds Jeong October 2015 Accepted 19 October 2015 Available online 21 October 2015 a b s t r a c t An in situ ion-irradiation irradiation-induced disordering and amorphization of Al3Ti-based intermetallic compounds. Thin foil samples

  1. Irradiated cubic single crystal SiC as a high temperature sensor Alex A. Volinsky

    E-Print Network [OSTI]

    Volinsky, Alex A.

    Irradiated cubic single crystal SiC as a high temperature sensor Alex A. Volinsky University the temperature of irradiation. Based on this effect the original technology of maximum temperature measurement on the phenomenon of SiC crystal lattice expansion as a result of irradiation [3] and consequently relieving

  2. Irradiation requirements of Nb3Sn based SC magnets electrical insulation

    E-Print Network [OSTI]

    McDonald, Kirk

    Irradiation requirements of Nb3Sn based SC magnets electrical insulation developed within the Eu and Power Engineering #12;Outline · Motivation of launching EuCARD irradiation task · Nb3Sn SC magnet coils electrical insulation candidates · EuCARD insulators certification conditions · Post irradiation tests

  3. POST-IRRADIATION PROPERTIES OF CANDIDATE MATERIALS FOR HIGH POWER TARGETS

    E-Print Network [OSTI]

    McDonald, Kirk

    POST-IRRADIATION PROPERTIES OF CANDIDATE MATERIALS FOR HIGH POWER TARGETS H. Kirk, N. Simos, P preliminary results of on-going experimental studies at BNL irradiation facilities. SEARCHING FOR SMART MATERIALS TO ACHIEVE >1 MW POWER Motivation Often dramatic change of key properties with irradiation (Figure

  4. Improved irradiances for use in ocean heating, primary production, and photo-oxidation calculations

    E-Print Network [OSTI]

    Boss, Emmanuel S.

    Improved irradiances for use in ocean heating, primary production, and photo-oxidation calculations- surface, broadband, daily averaged irradiance or photosynthetically available radiation (PAR) values or quantum units to in-water net irradiance, as needed for calculations of water heating, and to in- water

  5. Earth'sFuture Stratospheric ozone response to a solar irradiance reduction

    E-Print Network [OSTI]

    Jackman, Charles H.

    Earth'sFuture Stratospheric ozone response to a solar irradiance reduction in a quadrupled CO2) solar irradiance is imposed to help counteract a quadrupled CO2 atmo- sphere. This study is similar) a perturbed future atmosphere with 1140 ppmv CO2 and a 4% reduction in the TOA total solar irradiance (G1). We

  6. Irradiation-Induced Magnetism in Graphite: A Density Functional Study P. O. Lehtinen,1

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Irradiation-Induced Magnetism in Graphite: A Density Functional Study P. O. Lehtinen,1 A. S. Foster October 2004) Recent experiments indicate that proton irradiation triggers ferromagnetism in originally the origin of irradiation-induced magnetism, we have performed spin-polarized density functional theory

  7. TRENDS IN DIRECT NORMAL SOLAR IRRADIANCE IN OREGON FROM 1979-2003 Laura Riihimaki

    E-Print Network [OSTI]

    Oregon, University of

    TRENDS IN DIRECT NORMAL SOLAR IRRADIANCE IN OREGON FROM 1979-2003 Laura Riihimaki Frank Vignola of trends in direct normal irradiance from three sites around Oregon over a period of 25 years. An overall. This article studies the trends in direct normal beam irradiance at three locations in Oregon. These sites have

  8. Simulated Longwave Clearsky Irradiance over the Ocean: Spatial and Temporal Variability 19791993

    E-Print Network [OSTI]

    Allan, Richard P.

    Simulated Long­wave Clear­sky Irradiance over the Ocean: Spatial and Temporal Variability 1979.: OA8038 First author: Allan 1 Simulated Long­wave Clear­sky Irradiance over the Ocean: Spatial­wave irradiances calculated by a wide­band radiation code applied to the ECMWF re­analysis are used to investigate

  9. ClosedForm Expressions for Irradiance from NonUniform Lambertian

    E-Print Network [OSTI]

    Closed­Form Expressions for Irradiance from Non­Uniform Lambertian Luminaires Part II­Form Expressions for Irradiance from Non­Uniform Lambertian Luminaires Part II: Polynomially­Varying Radiant by generalizing the concepts of irradiance tensor and angular moment to rational forms and an arbitrary number

  10. Production of defects in hexagonal boron nitride monolayer under ion irradiation O. Lehtinen a,

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Production of defects in hexagonal boron nitride monolayer under ion irradiation O. Lehtinen a, , E: Hexagonal boron nitride monolayer Ion irradiation Defect a b s t r a c t Atomistic computer simulations monolayer to irradiation with noble gas ions having energies from 35 eV up to 10 MeV. Probabilities

  11. Effect of excimer laser irradiation on crystallinity and chemical bonding of biodegradable polymer

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    Effect of excimer laser irradiation on crystallinity and chemical bonding of biodegradable polymer: Biodegradable polymer Poly(L-lactic acid) Laser irradiation Chemical modification Crystallinity Radical mobility is favorable for surface treatment. The effects of excimer laser irradiation on the surface morphology

  12. The Effects of Ionizing Irradiation on Liquid, Dried, and Absorbed DNA Extracts

    E-Print Network [OSTI]

    The Effects of Ionizing Irradiation on Liquid, Dried, and Absorbed DNA Extracts With and Without from FBI and national public health experts, began irradiating mail to kill potentially present anthrax Formation in Irradiated Tubes High dose X ray Low dose X ray pH indicator wet dry D-BM wet dry D-BM wet dry

  13. TRANSPLANTATION Total body irradiation causes profound changes in endothelial traffic molecules

    E-Print Network [OSTI]

    von Andrian, Ulrich H.

    TRANSPLANTATION Total body irradiation causes profound changes in endothelial traffic molecules irradiation (TBI) changes the molecular mechanisms by which murine HPCs from fetal livers (FL) interact not re- quired. TBI increased the frequency of sticking FL HPC. This irradiation-induced additional

  14. A MALDI, TGA, TG/MS, and DEA study of the irradiation effects on PMMA

    E-Print Network [OSTI]

    Harmon, Julie P.

    A MALDI, TGA, TG/MS, and DEA study of the irradiation effects on PMMA S.R. Tatro, G.R. Baker, K October 2002 Abstract Poly(methyl methacrylate) (PMMA) (Mw ¼ 6.4 £ 103 , PD ¼ 1.06) was irradiated under(methyl methacrylate); Radiation 1. Introduction This study focuses on the irradiation of highly syndio- tactic poly

  15. A thermal spike model of grain growth under irradiation D. Kaoumi,1,a

    E-Print Network [OSTI]

    Motta, Arthur T.

    A thermal spike model of grain growth under irradiation D. Kaoumi,1,a A. T. Motta,1 and R. C The experimental study of grain growth in nanocrystalline metallic foils under ion irradiation showed the existence of a low-temperature regime below about 0.15­0.22Tm , where grain growth is independent of the irradiation

  16. The Columbia University microbeam II endstation for cell imaging and irradiation

    E-Print Network [OSTI]

    Brenner, David Jonathan

    The Columbia University microbeam II endstation for cell imaging and irradiation A.W. Bigelow *, G The Columbia University Microbeam II has been built to provide a focused ion beam for irradiating designated mammalian cells with single particles. With the interest in irradiating non-stained cells and cells in three

  17. EPR Study of the Surface Characteristics of Nanostructured TiO2 under UV Irradiation

    E-Print Network [OSTI]

    EPR Study of the Surface Characteristics of Nanostructured TiO2 under UV Irradiation Juan M irradiation in a vacuum show some Ti3+ centers. In contrast, under these conditions only weak signals activated by UV irradiation.1,2 However, reduced quantum yields, along with the gen- eration of undesired

  18. Target Material Irradiation Studies for High-Intensity Accelerator Beams , H. Ludewig1

    E-Print Network [OSTI]

    McDonald, Kirk

    Target Material Irradiation Studies for High-Intensity Accelerator Beams N. Simos1* , H. Kirk1 , H on the behavior of special materials and composites under irradiation conditions and their potential use irradiated target material. The ever greater deposited energy and induced thermo-mechanical loads combined

  19. Preparation and Irradiation of Ammonia as a Polarised Target for the COMPASS-Experiment

    E-Print Network [OSTI]

    Dutz, Hartmut

    Preparation and Irradiation of Ammonia as a Polarised Target for the COMPASS-Experiment Stefan Runkel Universit¨at Bonn December 7th 2011 Stefan Runkel Preparation and Irradiation of Ammonia 1/26 #12 characteristics Preparation and irradiation Quality measurements: Measurement of the Spin Density Measurement

  20. Temperature and ion irradiation dependence of magnetic domains and microstructure in CoPt multilayers

    E-Print Network [OSTI]

    Krishnan, Kannan M.

    Temperature and ion irradiation dependence of magnetic domains and microstructure in Co with perpendicular anisotropy were studied as a function of growth temperature (TG) and ion irradiation irradiation has been shown to modify the magnetic properties in such MLs by effectively reducing PMA.5­7 Hence

  1. Effects of ion bombardment on a two-dimensional target: Atomistic simulations of graphene irradiation

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    irradiation O. Lehtinen,1 J. Kotakoski,1 A. V. Krasheninnikov,1,2 A. Tolvanen,1 K. Nordlund,1 and J. Keinonen1-functional theory models, we study effects of ion irradiation on graphene. We identify the types and concentrations- tronic devices have been extensively studied.3,4 To assess the role of disorder, ion irradiation4­7 has

  2. Microwave photochemistry. Photoinitiated radical addition of tetrahydrofuran to peruorohexylethene under microwave irradiation

    E-Print Network [OSTI]

    Cirkva, Vladimir

    ¯uorohexylethene under microwave irradiation VladimõÂr CõÂrkva, Milan HaÂjek* Institute of Chemical Process Fundamentals combined irradiation using a new simple photochemical reactor developed for organic synthetic reactions reserved. Keywords: Radical addition; Microwave irradiation; Photoinitiation; Electrodeless UV lamp

  3. Sapphire (0 0 0 1) surface modifications induced by long-pulse 1054 nm laser irradiation

    E-Print Network [OSTI]

    Ma, Chi

    Sapphire (0 0 0 1) surface modifications induced by long-pulse 1054 nm laser irradiation Sheng fluences. Due to high temperature and elevated non-hydrostatic stresses upon laser irradiation, damage Elsevier B.V. All rights reserved. Keywords: Sapphire; Laser irradiation; Spall; Fracture; Twinning

  4. Heteronuclear Recoupling in Solid-State Magic-Angle-Spinning NMR via Overtone Irradiation

    E-Print Network [OSTI]

    Frydman, Lucio

    Heteronuclear Recoupling in Solid-State Magic-Angle-Spinning NMR via Overtone Irradiation Sungsool undergoing magic-angle- spinning (MAS) is introduced, based on the overtone irradiation of one of the coupled nuclei. It is shown that when I is a quadrupole, for instance 14N, irradiating this spin at a multiple

  5. Effects of high-temperature anneals and 60 Co gamma-ray irradiation

    E-Print Network [OSTI]

    Schroder, Dieter K.

    Effects of high-temperature anneals and 60 Co gamma-ray irradiation on strained silicon on insulator was exposed to high-temperature annealing and high-dose 60 Co gamma -ray irradiation to study at a rate of approximately 5 105 °C/s for millisecond duration anneals. For the irradiation experiments

  6. Investigation of the formation of nanostructures on silicon thin films by excimer laser irradiation

    E-Print Network [OSTI]

    Chaudhary, Vipin

    Investigation of the formation of nanostructures on silicon thin films by excimer laser irradiation-pulse excimer laser irradiation. The fabricated structures have heights of about 1 m and apical radii on an insulator substrate is irradiated in air environment with a single 25ns pulse from a KrF excimer laser

  7. Grain growth in ZrFe thin films during in situ ion irradiation in a TEM

    E-Print Network [OSTI]

    Motta, Arthur T.

    Grain growth in Zr­Fe thin films during in situ ion irradiation in a TEM D. Kaoumi a,*, A.T. Motta Laboratory, Argonne, IL 060493, USA Available online 2 November 2005 Abstract In situ ion-beam irradiation was used to study irradiation induced grain growth in co-sputter-deposited Zr/xFe (0% 6 x 6 4

  8. Magnetic and structural behavior of FeCo/Cu multilayers submitted to Kr irradiation

    E-Print Network [OSTI]

    Penkov, Julian Geshev

    Magnetic and structural behavior of FeCo/Cu multilayers submitted to Kr irradiation I.L. Graff Cedex, France Available online 19 January 2007 Abstract We have studied the effects of ion irradiation a phase transformation of FeCo alloy from bcc for the as-deposited sample to fcc after irradiation

  9. Kinetic Monte Carlo simulations of the response of carbon nanotubes to electron irradiation

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Kinetic Monte Carlo simulations of the response of carbon nanotubes to electron irradiation J of Technology, Finland (Dated: January 12, 2007) Irradiation is increasingly used nowadays to tailor of nanotubes to irradiation is still lacking, we have implemented the kinetic Monte Carlo method with Bortz

  10. Submitted for publication Production of defects in supported carbon nanotubes under ion irradiation

    E-Print Network [OSTI]

    Nordlund, Kai

    Submitted for publication Production of defects in supported carbon nanotubes under ion irradiation University of Helsinki, Finland (December 10, 2001) Ion irradiation of individual carbon nanotubes deposited near irradiation-induced defects. 81.07.De, 61.48+c, 61.80.Jh,73.22.-f I. INTRODUCTION Recent

  11. Principal Investigator: Guerrero, Thomas TITLE: Oral antisense oligonucleotides to mitigate GI crypt survival post-irradiation

    E-Print Network [OSTI]

    Warren, Joe

    GI crypt survival post-irradiation A. SPECIFIC AIMS Gastrointestinal (GI) injury is a major cause and contributor of death after whole-body irradiation (Jarrett 1999; NCRP 2001), agents to mitigate the effects inhibition of inflammation signaling by antisense drug therapy given orally post-irradiation in a mouse model

  12. Modifying the electronic structure of semiconducting single-walled carbon nanotubes ion irradiation

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    irradiation Antti Tolvanen,1 Gilles Buchs,2,3 Pascal Ruffieux,2 Pierangelo Gröning,2 Oliver Gröning,2-functional theory simulations with Ar- ion-irradiation experiments and low-temperature scanning tunneling microscopy and spectroscopy STM/STS characterization of the irradiated samples, we study the changes in the electronic

  13. Stability of irradiation-induced point defects on walls of carbon nanotubes A. V. Krasheninnikova)

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Stability of irradiation-induced point defects on walls of carbon nanotubes A. V. Krasheninnikova study the structure and stability of atomic-scale irradiation-induced defects on walls of carbon-dose, low-temperature ion irradiation, we model the temporal evolution of single vacancies and vacancy

  14. 11Physical mechanisms of enhanced conductivity in irradiated InOx nanocrystalline films

    E-Print Network [OSTI]

    Ovid'ko Ilya A.

    11Physical mechanisms of enhanced conductivity in irradiated InOx nanocrystalline films Study Center Co. Ltd. PHYSICAL MECHANISMS OF ENHANCED CONDUCTIVITY IN IRRADIATED InOx NANOCRYSTALLINE evolution in InOx nanocrystalline (nano-grained) films after UV light irradiation, and its dependence

  15. Microscopic analysis of irradiated AGR-1 coated particle fuel compacts

    SciTech Connect (OSTI)

    Scott Ploger; Paul Demkowicz; John Hunn; Robert Morris

    2012-10-01

    The AGR-1 experiment involved irradiation of 72 TRISO-coated particle fuel compacts to a peak burnup of 19.5% FIMA with no in-pile failures observed out of 3×105 total particles. Irradiated AGR-1 fuel compacts have been cross-sectioned and analyzed with optical microscopy to characterize kernel, buffer, and coating behavior. Five compacts have been examined so far, spanning a range of irradiation conditions (burnup, fast fluence, and irradiation temperature) and including all four TRISO coating variations irradiated in the AGR-1 experiment. The cylindrical specimens were sectioned both transversely and longitudinally, then polished to expose between approximately 40-80 individual particles on each mount. The analysis focused primarily on kernel swelling and porosity, buffer densification and fracturing, buffer-IPyC debonding, and fractures in the IPyC and SiC layers. Characteristic morphologies have been identified, over 800 particles have been classified, and spatial distributions of particle types have been mapped. No significant spatial patterns were discovered in these cross sections. However, some trends were found between morphological types and certain behavioral aspects. Buffer fractures were found in approximately 23% of the particles, and these fractures often resulted in unconstrained kernel swelling into the open cavities. Fractured buffers and buffers that stayed bonded to IPyC layers appear related to larger pore size in kernels. Buffer-IPyC interface integrity evidently factored into initiation of rare IPyC fractures. Fractures through part of the SiC layer were found in only three particles, all in conjunction with IPyC-SiC debonding. Compiled results suggest that the deliberate coating fabrication variations influenced the frequencies of IPyC fractures, IPyC-SiC debonds, and SiC fractures.

  16. Irradiation and annealing of p-type silicon carbide

    SciTech Connect (OSTI)

    Lebedev, Alexander A.; Bogdanova, Elena V.; Grigor'eva, Maria V.; Lebedev, Sergey P. [A.F. Ioffe Physical-Technical Institute, St. Petersburg, 194021 (Russian Federation); Kozlovski, Vitaly V. [St. Petersburg State Polytechnic University, St. Petersburg, 195251 (Russian Federation)

    2014-02-21

    The development of the technology of semiconductor devices based on silicon carbide and the beginning of their industrial manufacture have made increasingly topical studies of the radiation hardness of this material on the one hand and of the proton irradiation to form high-receptivity regions on the other hand. This paper reports on a study of the carrier removal rate (V{sub d}) in p-6H-SiC under irradiation with 8 MeV protons and of the conductivity restoration in radiation- compensated epitaxial layers of various p-type silicon carbide polytypes. V{sub d} was determined by analysis of capacitance-voltage characteristics and from results of Hall effect measurements. It was found that the complete compensation of samples with the initial value of Na - Nd ? 1.5 × 10{sup 18} cm{sup ?3} occurs at an irradiation dose of ?1.1 × 10{sup 16} cm{sup ?2}. It is shown that specific features of the sublimation layer SiC (compared to CVD layers) are clearly manifested upon the gamma and electron irradiation and are hardly noticeable under the proton and neutron irradiation. It was also found that the radiation-induced compensation of SiC is retained after its annealing at ?1000°C. The conductivity is almost completely restored at T ? 1200°C. This character of annealing of the radiation compensation is independent of a silicon carbide polytype and the starting doping level of the epitaxial layer. The complete annealing temperatures considerably exceed the working temperatures of SiC-based devices. It is shown that the radiation compensation is a promising method in the technology of high-temperature devices based on SiC.

  17. Characterization of the neutron irradiation system for use in the Low-Dose-Rate Irradiation Facility at Sandia National Laboratories.

    SciTech Connect (OSTI)

    Franco, Manuel,

    2014-08-01

    The objective of this work was to characterize the neutron irradiation system consisting of americium-241 beryllium (241AmBe) neutron sources placed in a polyethylene shielding for use at Sandia National Laboratories (SNL) Low Dose Rate Irradiation Facility (LDRIF). With a total activity of 0.3 TBq (9 Ci), the source consisted of three recycled 241AmBe sources of different activities that had been combined into a single source. The source in its polyethylene shielding will be used in neutron irradiation testing of components. The characterization of the source-shielding system was necessary to evaluate the radiation environment for future experiments. Characterization of the source was also necessary because the documentation for the three component sources and their relative alignment within the Special Form Capsule (SFC) was inadequate. The system consisting of the source and shielding was modeled using Monte Carlo N-Particle transport code (MCNP). The model was validated by benchmarking it against measurements using multiple techniques. To characterize the radiation fields over the full spatial geometry of the irradiation system, it was necessary to use a number of instruments of varying sensitivities. First, the computed photon radiography assisted in determining orientation of the component sources. With the capsule properly oriented inside the shielding, the neutron spectra were measured using a variety of techniques. A N-probe Microspec and a neutron Bubble Dosimeter Spectrometer (BDS) set were used to characterize the neutron spectra/field in several locations. In the third technique, neutron foil activation was used to ascertain the neutron spectra. A high purity germanium (HPGe) detector was used to characterize the photon spectrum. The experimentally measured spectra and the MCNP results compared well. Once the MCNP model was validated to an adequate level of confidence, parametric analyses was performed on the model to optimize for potential experimental configurations and neutron spectra for component irradiation. The final product of this work is a MCNP model validated by measurements, an overall understanding of neutron irradiation system including photon/neutron transport and effective dose rates throughout the system, and possible experimental configurations for future irradiation of components.

  18. Recent Accomplishments in the Irradiation Testing of Engineering-Scale Monolithic Fuel Specimens

    SciTech Connect (OSTI)

    N.E. Woolstenhulme; D.M. Wachs; M.K. Meyer; H.W. Glunz; R.B. Nielson

    2012-10-01

    The US fuel development team is focused on qualification and demonstration of the uranium-molybdenum monolithic fuel including irradiation testing of engineering-scale specimens. The team has recently accomplished the successful irradiation of the first monolithic multi-plate fuel element assembly within the AFIP-7 campaign. The AFIP-6 MKII campaign, while somewhat truncated by hardware challenges, exhibited successful irradiation of a large-scale monolithic specimen under extreme irradiation conditions. The channel gap and ultrasonic data are presented for AFIP-7 and AFIP-6 MKII, respectively. Finally, design concepts are summarized for future irradiations such as the base fuel demonstration and design demonstration experiment campaigns.

  19. Origins of ion irradiation-induced Ga nanoparticle motion on GaAs surfaces

    SciTech Connect (OSTI)

    Kang, M.; Wu, J. H.; Chen, H. Y.; Thornton, K.; Goldman, R. S. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States)] [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States); Sofferman, D. L. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States) [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States); Department of Physics, Adelphi University, Garden City, New York 11530-0701 (United States); Beskin, I. [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109-1040 (United States)] [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109-1040 (United States)

    2013-08-12

    We have examined the origins of ion irradiation-induced nanoparticle (NP) motion. Focused-ion-beam irradiation of GaAs surfaces induces random walks of Ga NPs, which are biased in the direction opposite to that of ion beam scanning. Although the instantaneous NP velocities are constant, the NP drift velocities are dependent on the off-normal irradiation angle, likely due to a difference in surface non-stoichiometry induced by the irradiation angle dependence of the sputtering yield. It is hypothesized that the random walks are initiated by ion irradiation-induced thermal fluctuations, with biasing driven by anisotropic mass transport.

  20. Microstructure and mechanical behavior of neutron irradiated ultrafine grained ferritic steel

    SciTech Connect (OSTI)

    Ahmad Alsabbagh; Apu Sarkar; Brandon Miller; Jatuporn Burns; Leah Squires; Douglas Porter; James I. Cole; K. L. Murty

    2014-10-01

    Neutron irradiation effects on ultra-fine grain (UFG) low carbon steel prepared by equal channel angular pressing (ECAP) has been examined. Counterpart samples with conventional grain (CG) sizes have been irradiated alongside with the UFG ones for comparison. Samples were irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) to 1.24 dpa. Atom probe tomography revealed manganese, silicon-enriched clusters in both ECAP and CG steel after neutron irradiation. X-ray quantitative analysis showed that dislocation density in CG increased after irradiation. However, no significant change was observed in UFG steel revealing better radiation tolerance.