National Library of Energy BETA

Sample records for ice melt system

  1. Complex systems influence melting of Greenland ice sheet

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

    Complex systems influence melting of Greenland ice sheet Complex systems influence melting of Greenland ice sheet International research team's field work shows that, well, things...

  2. Modeling the summertime evolution of sea-ice melt ponds rsted-DTU, Electromagnetic Systems, Technical University of Denmark, Lyngby, Denmark

    E-Print Network [OSTI]

    Feltham, Daniel

    Modeling the summertime evolution of sea-ice melt ponds M. Lu¨thje Ørsted-DTU, Electromagnetic of sea ice. We simulate the evolution of melt ponds and determine area coverage and total surface rate beneath the melt ponds, vertical seepage, and horizontal permeability. The model is initialized

  3. THE CONTRIBUTION OF GREENLAND ICE SHEET MELTING TO

    E-Print Network [OSTI]

    THE CONTRIBUTION OF GREENLAND ICE SHEET MELTING TO GLOBAL SEA-LEVEL CHANGE Conor Mc, orbital cycles, glacial isostatic adjustment and tectonics. Each of these elements contribute different it to be directly observed. This project examined the contribution to sea-level change due to melting of ice from

  4. Arctic melt ponds and bifurcations in the climate system

    E-Print Network [OSTI]

    Sudakov, Ivan; Golden, Kenneth M

    2014-01-01

    Understanding how sea ice melts is critical to climate projections. In the Arctic, melt ponds that develop on the surface of sea ice floes during the late spring and summer largely determine their albedo $-$ a key parameter in climate modeling. Here we explore the possibility of a simple sea ice climate model passing through a bifurcation point $-$ an irreversible critical threshold as the system warms, by incorporating geometric information about melt pond evolution. This study is based on a nonlinear phase transition model for melt ponds, and bifurcation analysis of a simple climate model with ice - albedo feedback as the key mechanism driving the system to a potential bifurcation point.

  5. Ising model for melt ponds on Arctic sea ice

    E-Print Network [OSTI]

    Ma, Y -P; Golden, K M

    2014-01-01

    The albedo of melting Arctic sea ice, a key parameter in climate modeling, is determined by pools of water on the ice surface. Recent observations show an onset of pond complexity at a critical area of about 100 square meters, attended by a transition in pond fractal dimension. To explain this behavior and provide a statistical physics approach to sea ice modeling, we introduce a two dimensional Ising model for pond evolution which incorporates ice-albedo feedback and the underlying thermodynamics. The binary magnetic spin variables in the Ising model correspond to the presence of melt water or ice on the sea ice surface. The model exhibits a second-order phase transition from isolated to clustered melt ponds, with the evolution of pond complexity in the clustered phase consistent with the observations.

  6. Incorporation of a physically based melt pond scheme into the sea ice component of a climate model

    E-Print Network [OSTI]

    Feltham, Daniel

    Incorporation of a physically based melt pond scheme into the sea ice component of a climate model and evolution of melt ponds. Melt ponds accumulate on the surface of sea ice from snow and sea ice melt, melt ponds cover up to 50% of the sea ice surface. We have developed a melt pond evolution theory. Here

  7. A model of the threedimensional evolution of Arctic melt ponds on firstyear and multiyear sea ice

    E-Print Network [OSTI]

    Feltham, Daniel

    A model of the threedimensional evolution of Arctic melt ponds on firstyear and multiyear sea ice F in Arctic melt ponds on the surface of sea ice. An accurate estimate of the fraction of the sea ice surface covered in melt ponds is essential for a realistic estimate of the albedo for global climate models. We

  8. Influence of tides on melting and freezing beneath FilchnerRonne Ice Shelf, Antarctica

    E-Print Network [OSTI]

    Holland, David

    Influence of tides on melting and freezing beneath FilchnerRonne Ice Shelf, Antarctica Keith doubles. With tidal forcing, the spatial pattern and magnitude of basal melting and freezing generally), Influence of tides on melting and freezing beneath FilchnerRonne Ice Shelf, Antarctica, Geophys. Res. Lett

  9. Sediment Melt-Migration Dynamics in Perennial Antarctic Lake Ice Steven M. Jepsen*

    E-Print Network [OSTI]

    Priscu, John C.

    Sediment Melt-Migration Dynamics in Perennial Antarctic Lake Ice Steven M. Jepsen* Edward E. Adams examined sediment melt-migration dynamics in the ice cover of Lake Fryxell, Taylor Valley, McMurdo Dry. The specific objectives were to determine the thermal conditions required for sediment melt and how sediment

  10. A continuum model of melt pond evolution on Arctic sea ice Daniela Flocco1

    E-Print Network [OSTI]

    Feltham, Daniel

    A continuum model of melt pond evolution on Arctic sea ice Daniela Flocco1 and Daniel L. Feltham1 to generate meltwater that accumulates in ponds. The melt ponds reduce the albedo of the sea ice cover during), which simulates the formation and evolution of the melt pond cover. In order to be compatible

  11. 2 Internal melting in Antarctic sea ice: Development of ``gap layers'' 3 S. F. Ackley,1

    E-Print Network [OSTI]

    Texas at San Antonio, University of

    accelerate melting by 63increasing the absorption of solar radiation within the sea 64ice. Algal blooms only in the Antarctic to date. 48 In contrast, massive surface melt, resulting in the complete 49 loss

  12. Large-Scale Oceanographic Constraints on the Distribution of Melting and Freezing under Ice Shelves

    E-Print Network [OSTI]

    Gnanadesikan, Anand

    Large-Scale Oceanographic Constraints on the Distribution of Melting and Freezing under Ice Shelves experience asymmetric melting and freezing. Topography may constrain oceanic circulation (and thus basal melt­freeze patterns) through its influence on the potential vorticity (PV) field. However, melting and freezing induce

  13. Arctic melt ponds and bifurcations in the climate system I. Sudakova,, S. A. Vakulenkob,c, K. M. Goldena

    E-Print Network [OSTI]

    Golden, Kenneth M.

    Arctic melt ponds and bifurcations in the climate system I. Sudakova,, S. A. Vakulenkob,c, K. M Abstract Understanding how sea ice melts is critical to climate projections. In the Arctic, melt ponds, by incorporating geometric information about melt pond evolution. This study is based on a bifurcation analysis

  14. High pressure melt ejection and direct containment heating in ice condenser containments

    SciTech Connect (OSTI)

    Pilch, M.; Tarbell, W.W.; Carroll, D.E.; Tills, J.L.

    1986-01-01

    A response of a typical ice condenser containment to a high pressure melt dispersal accident has been studied. While ice beds may be effective in reducing the potential loading caused by direct heating of the containment atmosphere, analyses suggest two other modes of containment failure that have not been previously identified. Calculations with the CONTAIN code indicate that ejected core debris may interact with steam from the primary system, generating sufficient hydrogen to threaten containment integrity. Further, if the debris ejected into the cavity promptly fails the seal table, the dispersed material could enter the in-core instrument room and attack the containment liner. The timing of the failure of the seal table is highly dependent on the characteristics of the debris-to-steel energy transfer.

  15. Some Thoughts on the Freezing and Melting of Sea Ice and Their Effects on the Ocean

    E-Print Network [OSTI]

    Washington at Seattle, University of

    Some Thoughts on the Freezing and Melting of Sea Ice and Their Effects on the Ocean K. Aagaard. The high-latitude freezing and melting cycle can variously result in haline con- vection, freshwater of this process is that water distilled at the surface of the Arctic Ocean by freezing ends up at mid

  16. 07/06/2009 Melting Ice Could Lead to Massive Waves of Climate Refugees Treehugger 06/30/2009 MELTING GREENLAND ICE SHEETS MAY THREATEN

    E-Print Network [OSTI]

    Hu, Aixue

    07/06/2009 Melting Ice Could Lead to Massive Waves of Climate Refugees Treehugger 06 Could Lead to Massive Waves of Climate Refugees Baltimore Chronicle & Sentinel, The 06/08/2009 Rapid Waves of Climate Refugees Green Options 06/04/2009 in the news Peterborough Examiner, The 06

  17. Basal melt rates beneath Whillans Ice Stream, West Antarctica

    E-Print Network [OSTI]

    Beem, Lucas H.; Jezek, Ken C.; van der Veen, Cornelis J.

    2010-08-05

    and J.E. Mitchell. 1994. The role of the margins in the dynamics of an active ice stream. J. Glaciol., 40(136), 527–538. Engelhardt, H. 2004a. Ice temperature and high geothermal flux at Siple Dome, West Antarctica, from borehole measurements. J. Glaciol... ratio which varies laterally across the shear margin. Basal drag, ?b, basal velocity, U(b), basal temperature gradient, @T/@z(b), esti- mates of geothermal flux, G, plus knowledge of basal ice properties, density, ?, latent heat of fusion of ice, Li...

  18. ARM - What About Melting Polar Ice Caps and Sea Levels?

    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,ProductstoacessProductsrlprofrlprofmerge1turnPlainsVisitingWhat About Melting

  19. Melting of the Patagonian Ice Sheet and deglacial perturbations of the nitrogen cycle in the eastern South Pacific

    E-Print Network [OSTI]

    Cattin, Rodolphe

    Melting of the Patagonian Ice Sheet and deglacial perturbations of the nitrogen cycle; published 18 February 2006. [1] We report the last glacial-interglacial transition of marine denitrification denitrification changes are in close agreement with the fresh-water pulses that resulted from the melting

  20. Thermal Storage with Ice Harvesting Systems 

    E-Print Network [OSTI]

    Knebel, D. E.

    1986-01-01

    Application of Harvesting Ice Storage Systems. Thermal storage systems are becoming widely accepted techniques for utility load management. This paper discusses the principles of ice harvesting equipment and their application to the multi...

  1. A three-phase free boundary problem with melting ice and dissolving gas

    E-Print Network [OSTI]

    Maurizio Ceseri; John M. Stockie

    2014-11-05

    We develop a mathematical model for a three-phase free boundary problem in one dimension that involves the interactions between gas, water and ice. The dynamics are driven by melting of the ice layer, while the pressurized gas also dissolves within the meltwater. The model incorporates a Stefan condition at the water-ice interface along with Henry's law for dissolution of gas at the gas-water interface. We employ a quasi-steady approximation for the phase temperatures and then derive a series solution for the interface positions. A non-standard feature of the model is an integral free boundary condition that arises from mass conservation owing to changes in gas density at the gas-water interface, which makes the problem non-self-adjoint. We derive a two-scale asymptotic series solution for the dissolved gas concentration, which because of the non-self-adjointness gives rise to a Fourier series expansion in eigenfunctions that do not satisfy the usual orthogonality conditions. Numerical simulations of the original governing equations are used to validate the series approximations.

  2. Early Mars climate near the NoachianHesperian boundary: Independent evidence for cold conditions from basal melting of the south polar ice sheet (Dorsa

    E-Print Network [OSTI]

    Marchant, David R.

    from basal melting of the south polar ice sheet (Dorsa Argentea Formation) and implications for valley of the Amazonian, the mean annual surface temperatures of Mars are so cold that basal melting does not occur in ice-developed eskers (sediment-filled former sub-glacial meltwater chan- nels) in the south circumpolar Dorsa Argentea

  3. Real-time Non-contact Millimeter Wave Characterization of Water-Freezing and Ice-Melting Dynamics

    E-Print Network [OSTI]

    Woskov, Paul P.

    We applied millimeter wave radiometry for the first time to monitor water-freezing and ice-melting dynamics in real-time non-contact. The measurements were completed at a frequency of 137 GHz. Small amounts (about 2 mL) ...

  4. arXiv:1408.2487v2[physics.ao-ph]22Aug2014 Ising model for melt ponds on Arctic sea ice

    E-Print Network [OSTI]

    Golden, Kenneth M.

    arXiv:1408.2487v2[physics.ao-ph]22Aug2014 Ising model for melt ponds on Arctic sea ice Yi-Ping Ma,1 of water on the ice surface. Recent observations show an onset of pond complexity at a critical area modeling, we introduce a two dimensional Ising model for pond evolution which incorporates ice

  5. Optimization of Ice Thermal Storage Systems Design for HVAC Systems 

    E-Print Network [OSTI]

    Nassif, N.; Hall, C.; Freelnad, D.

    2013-01-01

    energy cost. A tool for optimal ice storage design is developed, considering the charging and discharge times and optimal sizing of ice thermal storage system. Detailed simulation studies using real office building located near Orlando, FL including...

  6. ARKTOS: An intelligent system for SAR sea ice image classification

    E-Print Network [OSTI]

    Soh, L. K.; Tsatsoulis, Costas; Gineris, D.; Bertoia, C.

    2004-01-01

    We present an intelligent system for satellite sea ice image analysis named Advanced Reasoning using Knowledge for T ping Of Sea ice (ARKTOS). ARKTOS performs fully automated analysis of synthetic aperture radar (SAR) sea ice images by mimicking...

  7. Effect of Thermal Radiation on Melting Times of DT Ice Layers in Polymer-Capsule Targets for IFE Reactors

    SciTech Connect (OSTI)

    Gosnell, Timothy R.; Hoffer, James K. [Los Alamos National Laboratory (United States)

    2004-06-15

    Estimates of the time-to-melt for cryogenic DT inertial fusion targets in the presence of thermal radiation are presented. This time is defined as that required for thermal radiation in a hypothetical reactor to raise the temperature of small polymer capsules containing solid DT by 1 K and to fully liquefy the contents. The time estimates are in turn based on estimates of the infrared absorption spectra of both solid DT and the polymer capsule material. Assuming typical target dimensions and rapid equilibration of the target temperature, the estimates show that the absorption of thermal radiation and subsequent heating of likely capsule materials will dominate the corresponding quantities of DT ice and thus that the former effect largely determines the time-to-melt of the target. Specific estimates are made for capsules fabricated from Kapton{sup TM} polyimide. Comparisons are also made for capsules coated with reflective metal coatings, and the potential benefit of these coatings is discussed.

  8. Sediment plume response to surface melting and supraglacial lake drainages on the Greenland ice sheet

    E-Print Network [OSTI]

    Space Center, Technical University of Denmark, Ørsteds Plads Building 348, DK-2800 Kgs. Lyngby, Denmark-sheet melt extent from Special Sensor Microwave/Imager (SSM/I) passive microwave data; and (3) supraglacial extent and timing with passive microwave, thermal and scatterometer satellite data and show melt

  9. A model of melt pond evolution on sea ice P. D. Taylor and D. L. Feltham

    E-Print Network [OSTI]

    Feltham, Daniel

    , C12007, doi:10.1029/2004JC002361. 1. Introduction [2] Sea ice is formed by the freezing of seawater into the upper layers of the ocean. Drainage is believed to be the primary source of desalination of sea ice

  10. Spatial and temporal melt variability at Helheim Glacier, East Greenland, and its effect on ice dynamics

    E-Print Network [OSTI]

    Anderson, M. L.; Larsen, T. B.; Nettles, M.; Elosegui, P.; van As, D.; Hamilton, Gordon S.; Stearns, Leigh; Davis, J. L.; Ahlstrom, A. P.; de Juan, J.; Ekstrom, G.; Stenseng, L.; Khan, S. A.; Forsberg, R.; Dahl-Jensen, D.

    2010-12-29

    [1] Understanding the behavior of large outlet glaciers draining the Greenland Ice Sheet is critical for assessing the impact of climate change on sea level rise. The flow of marine-terminating outlet glaciers is partly governed by calving...

  11. Complex systems influence melting of Greenland ice sheet

    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 WebQuantityBonneville Power Administration would like submit the following commentsMethods for Estimating:ILaboratory Hydrides-AComplex

  12. Operation and Control of Full Ice-storage System 

    E-Print Network [OSTI]

    Liu, Q.; Liu, Y.

    2006-01-01

    In a dividing time ice-storage system, the refrigerator does not operate during power's on-peak period, and all the cooling is supplied by the ice stored in off-peak period, so that the use of electricity can be maintained. When the ice is thawing...

  13. CO2 isotopes as tracers of firn air diffusion and age in an Arctic ice cap with summer melting, Devon Island, Canada

    E-Print Network [OSTI]

    Chappellaz, Jérôme

    and the effects of summer melting. The 14 CO2 profile from the permeable firn includes the 1963 thermonuclear peak, and accumulation rates were calibrated with the depth of the 1963 thermonuclear 3 H peak. The average ages for CO2 and the ice matrix. Calibrated with the 1963 peak for thermonuclear 14 CO2, a 21.2-year reaction halftime

  14. Sensitive response of the Greenland Ice Sheet to surface melt drainage over soft bed

    E-Print Network [OSTI]

    Bougamont, M. H.; Christoffersen, P.; Hubbard, A.. L..; Fitzpatrick, A.. A..; Doyle, S. H.; Carter, S. P.

    2014-09-29

    by frictional and geothermal heating accumulates at the 136 bed over the course of winter and is released together with the first SGL drainage 137 events. With either one of these factors included, our model was able to reproduce the 138 2010 spring... . Measurements of ice 492 deformation, temperature and cross-borehole conductivity in boreholes to the 493 bedrock. Journal Of Glaciology 48, 369-385 (2002). 494 25 Pimentel, S. & Flowers, G. E. A numerical study of hydrologically driven 495 glacier dynamics...

  15. Field demonstration of the ICE 250{trademark} Cleaning System

    SciTech Connect (OSTI)

    Johnston, J.L.; Jackson, L.M.

    1999-10-05

    The ICE 250{trademark} Cleaning System was engineered to convert water into small ice particles for use in cleaning and decontamination applications. Ice crystals are produced in a special icemaker and pressured through a hose-nozzle onto the surface to be cleaned. The Rocky Mountain Oilfield Testing Center and Ice Cleaning Systems, Inc., conducted a test of this system at Naval Petroleum Reserve No. 3 to evaluate the system's cleaning capabilities in an oil field environment. Equipment cleaned included an oil storage tank, a rod pumping unit, a road grader, and a wellhead. Contaminants were unrefined sour crude oil, hydraulic fluid, paraffin, and dirt, occurring separately and as mixtures. In all four demonstration cleaning tasks, the ICE 250 System effectively removed surface contaminant mixtures in a timely manner and left no oily residue. A minimal amount of waste moisture was generated, thereby reducing cleanup and disposal costs.

  16. Air conditioning system with supplemental ice storing and cooling capacity

    DOE Patents [OSTI]

    Weng, Kuo-Lianq (Taichung, TW); Weng, Kuo-Liang (Taichung, TW)

    1998-01-01

    The present air conditioning system with ice storing and cooling capacity can generate and store ice in its pipe assembly or in an ice storage tank particularly equipped for the system, depending on the type of the air conditioning system. The system is characterized in particular in that ice can be produced and stored in the air conditioning system whereby the time of supplying cooled air can be effectively extended with the merit that the operation cycle of the on and off of the compressor can be prolonged, extending the operation lifespan of the compressor in one aspect. In another aspect, ice production and storage in great amount can be performed in an off-peak period of the electrical power consumption and the stored ice can be utilized in the peak period of the power consumption so as to provide supplemental cooling capacity for the compressor of the air conditioning system whereby the shift of peak and off-peak power consumption can be effected with ease. The present air conditioning system can lower the installation expense for an ice-storing air conditioning system and can also be applied to an old conventional air conditioning system.

  17. Sea ice in the paleoclimate system: the challenge of reconstructing sea ice from proxies e an introduction

    E-Print Network [OSTI]

    University, Denmark e Department of Earth Sciences, University of Cambridge, UK f British Antarctic Survey. In the climate system, sea ice cover generally acts as an amplifier: it in- fluences the energy budget). Under perennial sea ice there is generally little primary production apart from under special conditions

  18. Thesis proposal CSF Brazil 2014 Innovant de-icing system for more electric aircraft

    E-Print Network [OSTI]

    Bordenave, Charles

    . Mechanical de-icing systems are low energy solution that are focused on breaking down and shedding the ice-mechanical systems give a durable, light-weight, power-saver solution which justifies the recent efforts

  19. Fluid Flow and Thermodynamic Analysis of a Wing Anti-Icing System

    E-Print Network [OSTI]

    is controlled through regulating the hot flow passing a wing anti-icing valve by an automatic control system

  20. Experimental Investigation of Direct Expansion Dynamic Ice-on-coil Storage System Used in Residential Buildings 

    E-Print Network [OSTI]

    Zheng, M.; Kong, F.; Han, Z.; Liu, W.

    2006-01-01

    expansion dynamic ice-on-coil storage system that overcame the disadvantages of static and dynamic ice-storage system. It is concluded that periodic ice moving avoids the increased heat resistance that creates a decreased evaporating temperature. Due to a...

  1. USING THE UTAH ENERGY BALANCE SNOW MELT MODEL TO QUANTIFY SNOW AND GLACIER MELT IN THE HIMALAYAN REGION

    E-Print Network [OSTI]

    Tarboton, David

    USING THE UTAH ENERGY BALANCE SNOW MELT MODEL TO QUANTIFY SNOW AND GLACIER MELT IN THE HIMALAYAN of glacier ice as a substrate and generation of melt from the ice substrate when seasonal snow has melted for the entire domain. Therefore, regional variability in snow and glacier melting is computed. Outflow can

  2. Retrieval of Melt Pond Coverage from MODIS using Optimal Estimation 

    E-Print Network [OSTI]

    Dodd, Emma

    2011-11-24

    Melt pond coverage on sea ice is an important influence on sea ice albedo reduction during the summer and can also affect the monitoring of sea ice extent, sea ice models and sea ice forecasting. Techniques to estimate melt pond coverage from global...

  3. American Indian Complex to Cool Off Using Ice Storage System

    Broader source: Energy.gov [DOE]

    In Oklahoma City, summer temperatures can get above 100 degrees, making cooling more of a necessity than a luxury. But the designers of the American Indian Cultural Center and Museum (AICCM) wanted to make cooling choices that reflect American Indian cultures' respect for the land. So, rather than using conventional air-conditioning, the museum's main complex will use an ice storage system estimated to save 644,000 kilowatt hours of electricity a year.

  4. Process Systems Engineering Ice cream scheduling

    E-Print Network [OSTI]

    Grossmann, Ignacio E.

    storage tanks than mixers and packers - Model size largely determined by storage stage 328-9-2010 #12;S P Systems Engineering Intermediate storage 2. Considerably more storage tanks than mixers and packers Model runs Single continuous packing campaigns Mixer changes between products Only mixing full storage

  5. Ice shelf-ocean interactions in a general circulation model : melt-rate modulation due to mean flow and tidal currents

    E-Print Network [OSTI]

    Dansereau, Véronique

    2012-01-01

    Interactions between the ocean circulation in sub-ice shelf cavities and the overlying ice shelf have received considerable attention in the context of observed changes in flow speeds of marine ice sheets around Antarctica. ...

  6. Accurate freezing and melting equations for the Lennard-Jones system

    E-Print Network [OSTI]

    Sergey A. Khrapak; Gregor E. Morfill

    2011-04-14

    Analyzing three approximate methods to locate liquid-solid coexistence in simple systems, an observation is made that all of them predict the same functional dependence of the temperature on density at freezing and melting of the conventional Lennard-Jones system. The emerging equations can be written as $T={\\mathcal A}\\rho^4+{\\mathcal B}\\rho^2$ in normalized units. We suggest to determine the values of the coefficients ${\\mathcal A}$ at freezing and melting from the high-temperature limit, governed by the inverse twelfth power repulsive potential. The coefficients ${\\mathcal B}$ can be determined from the triple point parameters of the LJ fluid. This produces freezing and melting equations which are exact in the high-temperature limit and at the triple point, and show remarkably good agreement with numerical simulation data in the intermediate region.

  7. The Role of Snow and Ice in the Climate System

    SciTech Connect (OSTI)

    Barry, Roger G.

    2007-12-19

    Global snow and ice cover (the 'cryosphere') plays a major role in global climate and hydrology through a range of complex interactions and feedbacks, the best known of which is the ice - albedo feedback. Snow and ice cover undergo marked seasonal and long term changes in extent and thickness. The perennial elements - the major ice sheets and permafrost - play a role in present-day regional and local climate and hydrology, but the large seasonal variations in snow cover and sea ice are of importance on continental to hemispheric scales. The characteristics of these variations, especially in the Northern Hemisphere, and evidence for recent trends in snow and ice extent are discussed.

  8. The Role of Snow and Ice in the Climate System

    ScienceCinema (OSTI)

    Barry, Roger G.

    2009-09-01

    Global snow and ice cover (the 'cryosphere') plays a major role in global climate and hydrology through a range of complex interactions and feedbacks, the best known of which is the ice - albedo feedback. Snow and ice cover undergo marked seasonal and long term changes in extent and thickness. The perennial elements - the major ice sheets and permafrost - play a role in present-day regional and local climate and hydrology, but the large seasonal variations in snow cover and sea ice are of importance on continental to hemispheric scales. The characteristics of these variations, especially in the Northern Hemisphere, and evidence for recent trends in snow and ice extent are discussed.

  9. EXPERIMENTAL AND COMPUTATIONAL INVESTIGATION OF SNOW MELTING

    E-Print Network [OSTI]

    EXPERIMENTAL AND COMPUTATIONAL INVESTIGATION OF SNOW MELTING ON HEATED HORIZONTAL SURFACES By SEAN INVESTIGATION OF SNOW MELTING ON HEATED HORIZONTAL SURFACES Thesis Approved: Dean of the Graduate College Thesis..............................................................................................................5 2.3 Snow/Ice Physical Properties

  10. Melting temperatures of the ZrO{sub 2}-MOX system

    SciTech Connect (OSTI)

    Uchida, T.; Hirooka, S.; Kato, M.; Morimoto, K.; Sugata, H.; Shibata, K.; Sato, D.

    2013-07-01

    Severe accidents occurred at the Fukushima Daiichi Nuclear Power Plant Units 1-3 on March 11, 2011. MOX fuels were loaded in the Unit 3. For the thermal analysis of the severe accident, melting temperature and phase state of MOX corium were investigated. The simulated coriums were prepared from 4%Pu-containing MOX, 8%Pu-containing MOX and ZrO{sub 2}. Then X-ray diffraction, density and melting temperature measurements were carried out as a function of zirconium and plutonium contents. The cubic phase was observed in the 25%Zr-containing corium and the tetragonal phase was observed in the 50% and 75%Zr-containing coria. The lattice parameter and density monotonically changed with Pu content. Melting temperature increased with increasing Pu content; melting temperature were estimated to be 2932 K for 4%Pu MOX corium and 3012 K for 8%Pu MOX corium in the 25%ZrO{sub 2}-MOX system. The lowest melting temperature was observed for 50%Zr-containing corium. (authors)

  11. MODELING OF HYDRONIC AND ELECTRIC-CABLE SNOW-MELTING SYSTEMS FOR PAVEMENTS

    E-Print Network [OSTI]

    Smart Bridge Research Project at the Oklahoma State University with the close cooperationMODELING OF HYDRONIC AND ELECTRIC-CABLE SNOW-MELTING SYSTEMS FOR PAVEMENTS AND BRIDGE DECKS By XIA FOR PAVEMENTS AND BRIDGE DECKS Thesis Approved: _______________________________________________ Thesis Advisor

  12. A PHOTOMETRIC SYSTEM FOR DETECTION OF WATER AND METHANE ICES ON KUIPER BELT OBJECTS

    SciTech Connect (OSTI)

    Trujillo, Chadwick A.; Sheppard, Scott S.; Schaller, Emily L. E-mail: sheppard@dtm.ciw.edu

    2011-04-01

    We present a new near-infrared photometric system for detection of water ice and methane ice in the solar system. The system consists of two medium-band filters in the K-band region of the near-infrared, which are sensitive to water ice and methane ice, plus continuum observations in the J band and Y band. The primary purpose of this system is to distinguish between three basic types of Kuiper Belt Objects (KBOs)-those rich in water ice, those rich in methane ice, and those with little absorbance. In this work, we present proof-of-concept observations of 51 KBOs using our filter system, 21 of which have never been observed in the near-infrared spectroscopically. We show that our custom photometric system is consistent with previous spectroscopic observations while reducing telescope observing time by a factor of {approx}3. We use our filters to identify Haumea collisional family members, which are thought to be collisional remnants of a much larger body and are characterized by large fractions of water ice on their surfaces. We add 2009 YE{sub 7} to the Haumea collisional family based on our water ice band observations (J - H{sub 2}O = -1.03 {+-} 0.27) which indicate a high amount of water ice absorption, our calculated proper orbital elements, and the neutral optical colors we measured, V - R = 0.38 {+-} 0.04, which are all consistent with the rest of the Haumea family. We identify several objects dynamically similar to Haumea as being distinct from the Haumea family as they do not have water ice on their surfaces. In addition, we find that only the largest KBOs have methane ice, and Haumea itself has significantly less water ice absorption than the smaller Haumea family members. We find no evidence for other families in the Kuiper Belt.

  13. Ice electrode electrolytic cell

    DOE Patents [OSTI]

    Glenn, D.F.; Suciu, D.F.; Harris, T.L.; Ingram, J.C.

    1993-04-06

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  14. Ice electrode electrolytic cell

    DOE Patents [OSTI]

    Glenn, David F. (Idaho Falls, ID); Suciu, Dan F. (Idaho Falls, ID); Harris, Taryl L. (Idaho Falls, ID); Ingram, Jani C. (Idaho Falls, ID)

    1993-01-01

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  15. Weak chaos and the 'melting transition' in a confined microplasma system

    SciTech Connect (OSTI)

    Antonopoulos, Chris; Basios, Vasileios [Interdisciplinary Center for Nonlinear Phenomena and Complex Systems (CeNoLi), Service de Physique des Systemes Complexes et Mecanique Statistique, Universite Libre de Bruxelles, 1050 Brussels (Belgium); Bountis, Tassos [Center for Research and Applications of Nonlinear Systems (CRANS), Department of Mathematics, University of Patras, 26500 Patras (Greece)

    2010-01-15

    We present results demonstrating the occurrence of changes in the collective dynamics of a Hamiltonian system which describes a confined microplasma characterized by long-range Coulomb interactions. In its lower energy regime, we first detect macroscopically the transition from a 'crystallinelike' to a 'liquidlike' behavior, which we call the 'melting transition'. We then proceed to study this transition using a microscopic chaos indicator called the smaller alignment index (SALI), which utilizes two deviation vectors in the tangent dynamics of the flow and is nearly constant for ordered (quasiperiodic) orbits, while it decays exponentially to zero for chaotic orbits as exp[-(lambda{sub 1}-lambda{sub 2})t], where lambda{sub 1}>lambda{sub 2}>0 are the two largest Lyapunov exponents. During the melting phase, SALI exhibits a peculiar stairlike decay to zero, reminiscent of 'sticky' orbits of Hamiltonian systems near the boundaries of resonance islands. This alerts us to the importance of the DELTAlambda=lambda{sub 1}-lambda{sub 2} variations in that regime and helps us identify the energy range over which 'melting' occurs as a multistage diffusion process through weakly chaotic layers in the phase space of the microplasma. Additional evidence supporting further the above findings is given by examining the GALI{sub k} indices, which generalize SALI (=GALI{sub 2}) to the case of k>2 deviation vectors and depend on the complete spectrum of Lyapunov exponents of the tangent flow about the reference orbit.

  16. Oceanic control of the sea ice edge and multiple equilibria in the climate system

    E-Print Network [OSTI]

    Rose, Brian E. J. (Brian Edward James)

    2010-01-01

    I study fundamental mechanisms of atmosphere-ocean-sea ice interaction. Hierarchies of idealized models are invoked to argue that multiple equilibria and abrupt change are robust features of the climate system. The main ...

  17. Biogeochemistry in Sea Ice: CICE model developments

    SciTech Connect (OSTI)

    Jeffery, Nicole; Hunke, Elizabeth; Elliott, Scott; Turner, Adrian

    2012-06-18

    Polar primary production unfolds in a dynamic sea ice environment, and the interactions of sea ice with ocean support and mediate this production. In spring, for example, fresh melt water contributes to the shoaling of the mixed layer enhancing ice edge blooms. In contrast, sea ice formation in the fall reduces light penetration to the upper ocean slowing primary production in marine waters. Polar biogeochemical modeling studies typically consider these types of ice-ocean interactions. However, sea ice itself is a biogeochemically active medium, contributing a significant and, possibly, essential source of primary production to polar regions in early spring and fall. Here we present numerical simulations using the Los Alamos Sea Ice Model (CICE) with prognostic salinity and sea ice biogeochemistry. This study investigates the relationship between sea ice multiphase physics and sea ice productivity. Of particular emphasis are the processes of gravity drainage, melt water flushing, and snow loading. During sea ice formation, desalination by gravity drainage facilitates nutrient exchange between ocean and ice maintaining ice algal blooms in early spring. Melt water flushing releases ice algae and nutrients to underlying waters limiting ice production. Finally, snow loading, particularly in the Southern Ocean, forces sea ice below the ocean surface driving an upward flow of nutrient rich water into the ice to the benefit of interior and freeboard communities. Incorporating ice microphysics in CICE has given us an important tool for assessing the importance of these processes for polar algal production at global scales.

  18. Re-entrant melting and freezing in a model system of charged colloids

    E-Print Network [OSTI]

    C. Patrick Royall; Mirjam E. Leunissen; Antti-Pekka Hynninen; Marjolein Dijkstra; Alfons van Blaaderen

    2005-12-27

    We studied the phase behavior of charged and sterically stabilized colloids using confocal microscopy in a less polar solvent (dielectric constant 5.4). Upon increasing the colloid volume fraction we found a transition from a fluid to a body centered cubic crystal at 0.0415+/-0.0005, followed by re-entrant melting at 0.1165+/-0.0015. A second crystal of different symmetry, random hexagonal close-packed, was formed at a volume fraction around 0.5, similar to that of hard spheres. We attribute the intriguing phase behavior to particle interactions that depend strongly on volume fraction, mainly due to changes in the colloid charge. In this low polarity system the colloids acquire charge through ion adsorption. The low ionic strength leads to fewer ions per colloid at elevated volume fractions and consequently a density-dependent colloid charge.

  19. Modeling the evolution of polar ice sheets: Ice sheet system model workshop; Bergen, Norway, 2-4 June 2014

    E-Print Network [OSTI]

    Larour, E; Schlegel, N; Morlighem, M

    2014-01-01

    Model Workshop; Bergen, Norway, 2?4 June 2014 The Ice SheetUniversity of Bergen in Norway, in June 2014. This is the

  20. Warming of the arctic ice-ocean system is faster than the global average since the 1960s

    E-Print Network [OSTI]

    Zhang, Jinlun

    Warming of the arctic ice-ocean system is faster than the global average since the 1960s Jinlun.203°C. The warming of the world ocean is associated with an increase in global surface air temperature heat flux. Citation: Zhang, J. (2005), Warming of the arctic ice-ocean system is faster than the global

  1. Network Modeling of Arctic Melt Ponds Meenakshi Barjatiaa

    E-Print Network [OSTI]

    Golden, Kenneth M.

    Network Modeling of Arctic Melt Ponds Meenakshi Barjatiaa , Tolga Tasdizena,b, , Boya Songc. In late spring and summer, the albedo of the ice pack is determined primarily by melt ponds that form on the sea ice surface. The transition of pond configurations from isolated structures to interconnected

  2. Retrograde melting in transition metal-silicon systems : thermodynamic modeling, experimental verification, and potential application

    E-Print Network [OSTI]

    Fenning, David P

    2010-01-01

    A theoretical framework is presented in this work for retrograde melting in silicon driven by the retrograde solubility of low-concentration metallic solutes at temperatures above the binary eutectic. High enthalpy of ...

  3. *Deborah E. Eason, Garrett Ito, John M. Sinton Insights into melt and chemical transport rates in the mantle

    E-Print Network [OSTI]

    Geist, Dennis

    of glacial melting. Models of mantle decompression following ice sheet removal predict the greatest melt], we model melt migration in the mantle during and after ice sheet removal (glacial unloading*Deborah E. Eason, Garrett Ito, John M. Sinton Insights into melt and chemical transport rates

  4. Optimal Control of Harvesting Ice Thermal Storage Systems 

    E-Print Network [OSTI]

    Knebel, D. E.

    1988-01-01

    Thermal storage is becoming a standard consideration in HVAC and process cooling systems. As the technology is refined, more attention is being given to minimize the energy consumption and power demand requirements. This paper addresses a method...

  5. Implementation and Initial Evaluation of the Glimmer Community Ice Sheet Model in the Community Earth System Model

    E-Print Network [OSTI]

    Born, Andreas

    2013) ABSTRACT The Glimmer Community Ice Sheet Model (Glimmer-CISM) has been implemented in the Community Earth System Model (CESM). Glimmer-CISM is forced by a surface mass balance (SMB) computed

  6. Acceleration of Greenland ice mass loss in spring 2004

    E-Print Network [OSTI]

    Chen, Zhongping

    of increased melting at the ice sheet surface and increased glacial discharge at the coasts. All these trends, suggest that both accumulation and melting have increased during the past decade, with melting increasing thinning in the 1990s at low elevations8 where increased melting is probably more important than increased

  7. Ice Thermal Storage Systems for Nuclear Power Plant Supplemental Cooling and Peak Power Shifting

    SciTech Connect (OSTI)

    Haihua Zhao; Hongbin Zhang; Phil Sharpe; Blaise Hamanaka; Wei Yan; WoonSeong Jeong

    2013-03-01

    Availability of cooling water has been one of the major issues for the nuclear power plant site selection. Cooling water issues have frequently disrupted the normal operation at some nuclear power plants during heat waves and long draught. One potential solution is to use ice thermal storage (ITS) systems that reduce cooling water requirements and boost the plant’s thermal efficiency in hot hours. ITS uses cheap off-peak electricity to make ice and uses the ice for supplemental cooling during peak demand time. ITS also provides a way to shift a large amount of electricity from off peak time to peak time. For once-through cooling plants near a limited water body, adding ITS can bring significant economic benefits and avoid forced derating and shutdown during extremely hot weather. For the new plants using dry cooling towers, adding the ITS systems can effectively reduce the efficiency loss during hot weather so that new plants could be considered in regions lack of cooling water. This paper will review light water reactor cooling issues and present the feasibility study results.

  8. ICeL Systems Corp | Open Energy Information

    Open Energy Info (EERE)

    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 Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar2-0057-EA JumpDuimen RiverScoringUtilities Comm JumpImagingICFICeL Systems

  9. Optimizing the performance of Ice-storage Systems in Electricity Load Management through a credit mechanism. An analytical work for Jiangsu, China

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

    Han, Yafeng; Shen, Bo; Hu, Huajin; Fan, Fei

    2015-01-12

    Ice-storage air-conditioning is a technique that uses ice for thermal energy storage. Replacing existing air conditioning systems with ice storage has the advantage of shifting the load from on-peak times to off-peak times that often have excess generation. However, increasing the use of ice-storage faces significant challenges in China. One major barrier is the inefficiency in the current electricity tariff structure. There is a lack of effective incentive mechanism that induces ice-storage systems from achieving optimal load-shifting results. This study presents an analysis that compares the potential impacts of ice-storage systems on load-shifting under a new credit-based incentive scheme andmore »the existing incentive arrangement in Jiangsu, China. The study indicates that by changing how ice-storage systems are incentivized in Jiangsu, load-shifting results can be improved.« less

  10. Optimizing the performance of Ice-storage Systems in Electricity Load Management through a credit mechanism. An analytical work for Jiangsu, China

    SciTech Connect (OSTI)

    Han, Yafeng; Shen, Bo; Hu, Huajin; Fan, Fei

    2015-01-12

    Ice-storage air-conditioning is a technique that uses ice for thermal energy storage. Replacing existing air conditioning systems with ice storage has the advantage of shifting the load from on-peak times to off-peak times that often have excess generation. However, increasing the use of ice-storage faces significant challenges in China. One major barrier is the inefficiency in the current electricity tariff structure. There is a lack of effective incentive mechanism that induces ice-storage systems from achieving optimal load-shifting results. This study presents an analysis that compares the potential impacts of ice-storage systems on load-shifting under a new credit-based incentive scheme and the existing incentive arrangement in Jiangsu, China. The study indicates that by changing how ice-storage systems are incentivized in Jiangsu, load-shifting results can be improved.

  11. Thermal Storage Options for HVAC Systems 

    E-Print Network [OSTI]

    Weston, R. F.; Gidwani, B. N.

    1986-01-01

    is based on the specific heat of water rather than the latent 'heat of fusion of ice as in ice storage, it requires about 4 times the storage capacity of an equivalent ice storage system. ? Salt Storage: This system utilizes eutectic salts which... freeze and melt around 47 o F. Exist ing chillers can be easily retrofitted for salt storage or chilled water storage. For ice stor age systems, a direct refrigerant system or glycol chillers are suitable. This paper discusses the details of each...

  12. Ice Thermal Storage Systems for LWR Supplemental Cooling and Peak Power Shifting

    SciTech Connect (OSTI)

    Haihua Zhao; Hongbin Zhang; Phil Sharpe; Blaise Hamanaka; Wei Yan; WoonSeong Jeong

    2010-06-01

    Availability of enough cooling water has been one of the major issues for the nuclear power plant site selection. Cooling water issues have frequently disrupted the normal operation at some nuclear power plants during heat waves and long draught. The issues become more severe due to the new round of nuclear power expansion and global warming. During hot summer days, cooling water leaving a power plant may become too hot to threaten aquatic life so that environmental regulations may force the plant to reduce power output or even temporarily to be shutdown. For new nuclear power plants to be built at areas without enough cooling water, dry cooling can be used to remove waste heat directly into the atmosphere. However, dry cooling will result in much lower thermal efficiency when the weather is hot. One potential solution for the above mentioned issues is to use ice thermal storage systems (ITS) that reduce cooling water requirements and boost the plant’s thermal efficiency in hot hours. ITS uses cheap off-peak electricity to make ice and uses those ice for supplemental cooling during peak demand time. ITS is suitable for supplemental cooling storage due to its very high energy storage density. ITS also provides a way to shift large amount of electricity from off peak time to peak time. Some gas turbine plants already use ITS to increase thermal efficiency during peak hours in summer. ITSs have also been widely used for building cooling to save energy cost. Among three cooling methods for LWR applications: once-through, wet cooling tower, and dry cooling tower, once-through cooling plants near a large water body like an ocean or a large lake and wet cooling plants can maintain the designed turbine backpressure (or condensation temperature) during 99% of the time; therefore, adding ITS to those plants will not generate large benefits. For once-through cooling plants near a limited water body like a river or a small lake, adding ITS can bring significant economic benefits and avoid forced derating and shutdown during extremely hot weather. For the new plants using dry cooling towers, adding the ice thermal storage systems can effectively reduce the efficiency loss and water consumption during hot weather so that new LWRs could be considered in regions without enough cooling water. \\ This paper presents the feasibility study of using ice thermal storage systems for LWR supplemental cooling and peak power shifting. LWR cooling issues and ITS application status will be reviewed. Two ITS application case studies will be presented and compared with alternative options: one for once-through cooling without enough cooling for short time, and the other with dry cooling. Because capital cost, especially the ice storage structure/building cost, is the major cost for ITS, two different cost estimation models are developed: one based on scaling method, and the other based on a preliminary design using Building Information Modeling (BIM), an emerging technology in Architecture/Engineering/Construction, which enables design options, performance analysis and cost estimating in the early design stage.

  13. Electrothermal Icing Protection of Aerosurfaces Using Conductive Polymer Nanocomposites

    E-Print Network [OSTI]

    Buschhorn, Samuel T.

    Ice protection systems (IPS) are critical components for many aerospace flight vehicles, including commercial transports and unmanned aerial systems (UAS), and can include anti-icing, de-icing, ice sensing, etc. Here, an ...

  14. Fluid Migration During Ice/Rock Planetesimal Differentiation 

    E-Print Network [OSTI]

    Raney, Robert 1987-

    2012-12-12

    fast melt water can segregate from the core of an ice-rich planetesimal. To answer this question we treat the core as two phase flow problem: a compacting viscous “solid” (ice/rock mixture) and a segregating liquid (melt water). The model developed...

  15. Liu, Rees and Spitler. 1 Simulation of a Geothermal Bridge Deck Anti-icing System and Experimental Validation

    E-Print Network [OSTI]

    Liu, Rees and Spitler. 1 Simulation of a Geothermal Bridge Deck Anti-icing System and Experimental and a ground-coupled heat pump system with vertical borehole heat exchangers as a heat source. The models pumps that, in turn, extract heat with the ground via vertical U-tube borehole heat exchangers (Fig.1

  16. Cryoconite Hole Ecosystems in Antarctic Glacier Ice Brent C. Christner, Montana State University, Department of Land

    E-Print Network [OSTI]

    Christner, Brent C.

    released from the melted glacial ice and attached to deposited airborne particulates provide the biological glacial melting. Cryoconite hole ecosystems exist and thrive under the harsh conditions associated, are warmed by the sun, and melt into the ice producing a cylindrical basin of liquid water. Organisms

  17. Ice-shelf melting around antarctica

    E-Print Network [OSTI]

    Rignot, E; Jacobs, S; Mouginot, J; Scheuchl, B

    2013-01-01

    Ronne Larsen B Larsen C Rayner Thyer Stancomb Brunt Edwardyear (m/year) Edward VIII Rayner/Thyer Shirase Prince Harald

  18. Ice-shelf melting around antarctica

    E-Print Network [OSTI]

    Rignot, E; Rignot, E; Jacobs, S; Mouginot, J; Scheuchl, B

    2013-01-01

    27. D. D. Bogard, D. H. Garrison, Meteorit. Planet. Sci.L. Fox, Icarus 37. D. H. Garrison, D. D. Bogard, Meteorit.

  19. Ice-shelf melting around antarctica

    E-Print Network [OSTI]

    Rignot, E; Rignot, E; Jacobs, S; Mouginot, J; Scheuchl, B

    2013-01-01

    year (m/year) Edward VIII Rayner/Thyer Shirase Prince HaraldPrince Harald Shirase Weddell Sea Ronne Larsen B Larsen C Rayner Thyer Stancomb Brunt Edward

  20. ARM - Lesson Plans: When Land Ice Melts

    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 Home Room News PublicationsClimatePastThe PacificWeatherWhen

  1. Arctic Sea ice model sensitivities.

    SciTech Connect (OSTI)

    Peterson, Kara J.; Bochev, Pavel Blagoveston; Paskaleva, Biliana Stefanova

    2010-12-01

    Arctic sea ice is an important component of the global climate system and, due to feedback effects, the Arctic ice cover is changing rapidly. Predictive mathematical models are of paramount importance for accurate estimates of the future ice trajectory. However, the sea ice components of Global Climate Models (GCMs) vary significantly in their prediction of the future state of Arctic sea ice and have generally underestimated the rate of decline in minimum sea ice extent seen over the past thirty years. One of the contributing factors to this variability is the sensitivity of the sea ice state to internal model parameters. A new sea ice model that holds some promise for improving sea ice predictions incorporates an anisotropic elastic-decohesive rheology and dynamics solved using the material-point method (MPM), which combines Lagrangian particles for advection with a background grid for gradient computations. We evaluate the variability of this MPM sea ice code and compare it with the Los Alamos National Laboratory CICE code for a single year simulation of the Arctic basin using consistent ocean and atmospheric forcing. Sensitivities of ice volume, ice area, ice extent, root mean square (RMS) ice speed, central Arctic ice thickness,and central Arctic ice speed with respect to ten different dynamic and thermodynamic parameters are evaluated both individually and in combination using the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA). We find similar responses for the two codes and some interesting seasonal variability in the strength of the parameters on the solution.

  2. Passive ice freezing-releasing heat pipe

    DOE Patents [OSTI]

    Gorski, Anthony J. (Lemont, IL); Schertz, William W. (Batavia, IL)

    1982-01-01

    A heat pipe device has been developed which permits completely passive ice formation and periodic release of ice without requiring the ambient temperature to rise above the melting point of water. This passive design enables the maximum amount of cooling capacity to be stored in the tank.

  3. Technique for continuous high-resolution analysis of trace substances in firn and ice cores

    SciTech Connect (OSTI)

    Roethlisberger, R.; Bigler, M.; Hutterli, M.; Sommer, S.; Stauffer, B.; Junghans, H.G.; Wagenbach, D.

    2000-01-15

    The very successful application of a CFA (Continuous flow analysis) system in the GRIP project (Greenland Ice Core Project) for high-resolution ammonium, calcium, hydrogen peroxide, and formaldehyde measurements along a deep ice core led to further development of this analysis technique. The authors included methods for continuous analysis technique. The authors included methods for continuous analysis of sodium, nitrate, sulfate, and electrolytical conductivity, while the existing methods have been improved. The melting device has been optimized to allow the simultaneous analysis of eight components. Furthermore, a new melter was developed for analyzing firn cores. The system has been used in the frame of the European Project for Ice Coring in Antarctica (EPICA) for in-situ analysis of several firn cores from Dronning Maud Land, Antarctica, and for the new ice core drilled at Dome C, Antarctica.

  4. Synchrotron X-ray Diffraction Investigation of the Anomalous Behavior of Ice During Freezing of Aqueous Systems

    E-Print Network [OSTI]

    Elliott, James

    Synchrotron X-ray Diffraction Investigation of the Anomalous Behavior of Ice During Freezing be used to quantify stresses during freezing, which could improve our understanding of the role of water, such as freeze-induced destabilization of biological systems, and laboratory or industrial practices

  5. Blast from the Past: Melting Glaciers as a Relevant Source for

    E-Print Network [OSTI]

    Gilli, Adrian

    melting in the future (1). Glacial ice may contain significant amounts of chemicals deposited in earlierBlast from the Past: Melting Glaciers as a Relevant Source for Persistent Organic Pollutants C H R, 2009. Accepted August 31, 2009. In this study, the hypothesis that melting Alpine glaciers may

  6. Surface energy balance and melt thresholds over 11 years at Taylor Glacier, Antarctica

    E-Print Network [OSTI]

    Fountain, Andrew G.

    , Antarctica, melting of glacial ice is the primary source of water to streams, lakes, and associated, 1981; Gooseff et al., 2006]. Consequently, glacial melt is the critically important water source an understanding of glacial melt- water production. [3] Past runoff modeling for the MDV has included both

  7. Using Temporal Information in an Automated Classification of Summer, Marginal Ice Zone Imagery*

    E-Print Network [OSTI]

    Kansas, University of

    * Donna Haverkamp and Costas Tsatsoulis Department of Electrical Engineering and Computer Science- analyzed temperature records and regional statistics in order to achieve an automated ice's ice/water concentrations and melt state with temperature and wind data, a current interpretation

  8. Co-gasification of municipal solid waste and material recovery in a large-scale gasification and melting system

    SciTech Connect (OSTI)

    Tanigaki, Nobuhiro; Manako, Kazutaka; Osada, Morihiro

    2012-04-15

    Highlights: Black-Right-Pointing-Pointer This study evaluates the effects of co-gasification of MSW with MSW bottom ash. Black-Right-Pointing-Pointer No significant difference between MSW treatment with and without MSW bottom ash. Black-Right-Pointing-Pointer PCDD/DFs yields are significantly low because of the high carbon conversion ratio. Black-Right-Pointing-Pointer Slag quality is significantly stable and slag contains few hazardous heavy metals. Black-Right-Pointing-Pointer The final landfill amount is reduced and materials are recovered by DMS process. - Abstract: This study evaluates the effects of co-gasification of municipal solid waste with and without the municipal solid waste bottom ash using two large-scale commercial operation plants. From the viewpoint of operation data, there is no significant difference between municipal solid waste treatment with and without the bottom ash. The carbon conversion ratios are as high as 91.7% and 95.3%, respectively and this leads to significantly low PCDD/DFs yields via complete syngas combustion. The gross power generation efficiencies are 18.9% with the bottom ash and 23.0% without municipal solid waste bottom ash, respectively. The effects of the equivalence ratio are also evaluated. With the equivalence ratio increasing, carbon monoxide concentration is decreased, and carbon dioxide and the syngas temperature (top gas temperature) are increased. The carbon conversion ratio is also increased. These tendencies are seen in both modes. Co-gasification using the gasification and melting system (Direct Melting System) has a possibility to recover materials effectively. More than 90% of chlorine is distributed in fly ash. Low-boiling-point heavy metals, such as lead and zinc, are distributed in fly ash at rates of 95.2% and 92.0%, respectively. Most of high-boiling-point heavy metals, such as iron and copper, are distributed in metal. It is also clarified that slag is stable and contains few harmful heavy metals such as lead. Compared with the conventional waste management framework, 85% of the final landfill amount reduction is achieved by co-gasification of municipal solid waste with bottom ash and incombustible residues. These results indicate that the combined production of slag with co-gasification of municipal solid waste with the bottom ash constitutes an ideal approach to environmental conservation and resource recycling.

  9. Energy policies avoiding a tipping point in the climate system Olivier Bahn a,, Neil R. Edwards b

    E-Print Network [OSTI]

    Stocker, Thomas

    emission reduction from today's level, with transition to nuclear and/or renewable energy, possiblyEnergy policies avoiding a tipping point in the climate system Olivier Bahn a,Ã, Neil R. Edwards b rainforest, loss of Arctic summer sea ice, melting of the West Antarctic ice sheet, and a collapse

  10. Research on direct containment heating and pressurized melt expulsion from the reactor coolant system

    SciTech Connect (OSTI)

    Tarbell, W.W.; Pilch, M.; Brockmann, J.E.; Powers, D.A.

    1988-01-01

    The expulsion of high temperature core debris from the reactor cavity into the containment atmosphere has recently been identified as an important potential contributor to containment failure in the event of a severe accident. Experiments and analyses have shown that failure of the reactor vessel while the primary system is pressurized can result in the rapid discharge of molten core debris into the cavity. Gas from the blowdown of the coolant system may then entrain the debris as fine particulate that may be carried out of the cavity region. Containment loading can result from the combustion of hydrogen produced by the interaction of the debris with steam from the primary system and from thermal and chemical energy transferred from the debris to the atmosphere is directed towards identifying and quantifying the phenomena associated with the pressurized discharge of the core debris and the direct containment heating processes. Experiments are being performed to provide the information needed to develop phenomenological models for use in system level code predictions. Emphasis has been primarily on the use of scaled cavities (ranging from 1:10 to 1:50 linear scale) and the quantification of the extent of the material dispersed. Information has been obtained on the physics of the jet behavior, the entrainment of the debris, debris characteristics (e.g., size and number distributions), debris-gas heat transfer and chemistry, aerosol generation, and the influence of water. Models and codes are reviewed and discussed and representative calculations are presented.

  11. Vapor deposition of water on graphitic surfaces: Formation of amorphous ice, bilayer ice, ice I, and liquid water

    SciTech Connect (OSTI)

    Lupi, Laura; Kastelowitz, Noah; Molinero, Valeria

    2014-11-14

    Carbonaceous surfaces are a major source of atmospheric particles and could play an important role in the formation of ice. Here we investigate through molecular simulations the stability, metastability, and molecular pathways of deposition of amorphous ice, bilayer ice, and ice I from water vapor on graphitic and atomless Lennard-Jones surfaces as a function of temperature. We find that bilayer ice is the most stable ice polymorph for small cluster sizes, nevertheless it can grow metastable well above its region of thermodynamic stability. In agreement with experiments, the simulations predict that on increasing temperature the outcome of water deposition is amorphous ice, bilayer ice, ice I, and liquid water. The deposition nucleation of bilayer ice and ice I is preceded by the formation of small liquid clusters, which have two wetting states: bilayer pancake-like (wetting) at small cluster size and droplet-like (non-wetting) at larger cluster size. The wetting state of liquid clusters determines which ice polymorph is nucleated: bilayer ice nucleates from wetting bilayer liquid clusters and ice I from non-wetting liquid clusters. The maximum temperature for nucleation of bilayer ice on flat surfaces, T{sub B}{sup max} is given by the maximum temperature for which liquid water clusters reach the equilibrium melting line of bilayer ice as wetting bilayer clusters. Increasing water-surface attraction stabilizes the pancake-like wetting state of liquid clusters leading to larger T{sub B}{sup max} for the flat non-hydrogen bonding surfaces of this study. The findings of this study should be of relevance for the understanding of ice formation by deposition mode on carbonaceous atmospheric particles, including soot.

  12. Analysis of Cloud-resolving Simulations of a Tropical Mesoscale Convective System Observed during TWP-ICE: Vertical Fluxes and Draft Properties in Convective and Stratiform Regions

    SciTech Connect (OSTI)

    Mrowiec, Agnieszka A.; Rio, Catherine; Fridlind, Ann; Ackerman, Andrew; Del Genio, Anthony D.; Pauluis, Olivier; Varble, Adam; Fan, Jiwen

    2012-10-02

    We analyze three cloud-resolving model simulations of a strong convective event observed during the TWP-ICE campaign, differing in dynamical core, microphysical scheme or both. Based on simulated and observed radar reflectivity, simulations roughly reproduce observed convective and stratiform precipitating areas. To identify the characteristics of convective and stratiform drafts that are difficult to observe but relevant to climate model parameterization, independent vertical wind speed thresholds are calculated to capture 90% of total convective and stratiform updraft and downdraft mass fluxes. Convective updrafts are fairly consistent across simulations (likely owing to fixed large-scale forcings and surface conditions), except that hydrometeor loadings differ substantially. Convective downdraft and stratiform updraft and downdraft mass fluxes vary notably below the melting level, but share similar vertically uniform draft velocities despite differing hydrometeor loadings. All identified convective and stratiform downdrafts contain precipitation below ~10 km and nearly all updrafts are cloudy above the melting level. Cold pool properties diverge substantially in a manner that is consistent with convective downdraft mass flux differences below the melting level. Despite differences in hydrometeor loadings and cold pool properties, convective updraft and downdraft mass fluxes are linearly correlated with convective area, the ratio of ice in downdrafts to that in updrafts is ~0.5 independent of species, and the ratio of downdraft to updraft mass flux is ~0.5-0.6, which may represent a minimum evaporation efficiency under moist conditions. Hydrometeor loading in stratiform regions is found to be a fraction of hydrometeor loading in convective regions that ranges from ~10% (graupel) to ~90% (cloud ice). These findings may lead to improved convection parameterizations.

  13. Flight tests of a digital data acquisition system for analysis of ultrasonic pulse-echo signals used to measure ice accretion

    E-Print Network [OSTI]

    Ryan, Justin Mark

    1986-01-01

    A number of signal processing algorithms were developed for analyzing ultrasonic signals used to measure aircraft ice accretion in flight. A high speed digital signal acquisition system was designed and constructed to ...

  14. Experimental investigations at high temperatures and pressures on melting and mineral solubility in systems of feldspars with water, with special reference to the origin of granite

    E-Print Network [OSTI]

    Makhluf, Adam Rafiq

    2015-01-01

    mixing properties of albite-water melts. Transactions of themelting and activities of water at high pressures. Americanfor determining the solubility of water in silicate melts.

  15. Turbulent heat exchange between water and ice at an evolving ice-water interface

    E-Print Network [OSTI]

    Ramudu, Eshwan; Olson, Peter; Gnanadesikan, Anand

    2015-01-01

    We conduct laboratory experiments on the time evolution of an ice layer cooled from below and subjected to a turbulent shear flow of warm water from above. Our study is motivated by observations of warm water intrusion into the ocean cavity under Antarctic ice shelves, accelerating the melting of their basal surfaces. The strength of the applied turbulent shear flow in our experiments is represented in terms of its Reynolds number $\\textit{Re}$, which is varied over the range $2.0\\times10^3 \\le \\textit{Re} \\le 1.0\\times10^4$. Depending on the water temperature, partial transient melting of the ice occurs at the lower end of this range of $\\textit{Re}$ and complete transient melting of the ice occurs at the higher end. Following these episodes of transient melting, the ice reforms at a rate that is independent of $\\textit{Re}$. We fit our experimental measurements of ice thickness and temperature to a one-dimensional model for the evolution of the ice thickness in which the turbulent heat transfer is parameter...

  16. Energy optimization in ice hockey halls I. The system COP as a multivariable function, brine and design choices

    E-Print Network [OSTI]

    Andrea Ferrantelli; Paul Melóis; Miska Räikkönen; Martti Viljanen

    2013-05-03

    This work is the first in a series of articles addressing the energy optimization in ice hockey halls. Here we adopt an analytical method, called functional optimization, to find which design and operating conditions maximize the Coefficient Of Performance of the entire cooling system (brine pumps and cooling tower), which we call ${\\rm COP}_{sys}$. This is addressed as a function of several variables, like electric consumption and brine physical properties. By maximizing such function, the best configuration and brine choices for the system can thus be determined accurately and rigorously. We investigate the importance of pipe diameter, depth and brine type (ethylene glycol and ammonia) for average-sized ice rinks. An optimal brine density is found, and we compute the weight of the electric consumption of the brine pumps on ${\\rm COP}_{sys}$. Our formulas are validated with heat flow measurement data obtained at an ice hockey hall in Finland. They are also confronted with technical and cost-related constraints, and implemented by simulations with the program COMSOL Multiphysics. The multivariable approach here discussed is general, and can be applied to the rigorous preliminary study of diverse situations in building physics and in many other areas of interest.

  17. Predicting Land-Ice Retreat and Sea-Level Rise with the Community Earth System Model

    SciTech Connect (OSTI)

    Lipscomb, William

    2012-06-19

    Coastal stakeholders need defensible predictions of 21st century sea-level rise (SLR). IPCC assessments suggest 21st century SLR of {approx}0.5 m under aggressive emission scenarios. Semi-empirical models project SLR of {approx}1 m or more by 2100. Although some sea-level contributions are fairly well constrained by models, others are highly uncertain. Recent studies suggest a potential large contribution ({approx}0.5 m/century) from the marine-based West Antarctic Ice Sheet, linked to changes in Southern Ocean wind stress. To assess the likelihood of fast retreat of marine ice sheets, we need coupled ice-sheet/ocean models that do not yet exist (but are well under way). CESM is uniquely positioned to provide integrated, physics based sea-level predictions.

  18. Hydrological and biogeochemical cycling along the Greenland ice sheet margin

    E-Print Network [OSTI]

    Bhatia, Maya Pilar, 1979-

    2012-01-01

    Global warming has led to a significant increase in Greenland ice sheet (GrIS) melt and runoff since 1990, resulting in escalated export of fresh water and associated sediment to the surrounding North Atlantic and Arctic ...

  19. Iced Coffee Iced Chai Tea Latte

    E-Print Network [OSTI]

    Iced Coffee Iced Chai Tea Latte Iced Americano Iced Cappuccino Iced Latte Iced Mocha Iced White the Cooler Canned Soda Bottled Water Arizona Teas Energy Drinks Red Bull, SF Red Bull & Bing Jones Sodas $0.50 Listed prices do not include applicable sales tax. #12;Brewed Coffee Cafe au Lait Hot Tea Chai Tea Latte

  20. ICE SHEETS, GLOBAL WARMING, AND ARTICLE 2 OF THE UNFCCC An Editorial Essay

    E-Print Network [OSTI]

    Oppenheimer, Michael

    in area and perhaps in mass since the Last Glacial Maximum (Bindschadler, 1998; Huybrechts, 2002) provides of ice loss by altering the mass balance between precipitation rates on the one hand, and melting and ice site has been tied to the availability of surface melt water, which percolates to and lubricates

  1. LABORATORY STUDIES ON THE IRRADIATION OF METHANE IN INTERSTELLAR, COMETARY, AND SOLAR SYSTEM ICES

    E-Print Network [OSTI]

    Kaiser, Ralf I.

    on the identification of CHx (x ¼ 1Y4) and C2Hx (x ¼ 2Y6) species and also investigates their formation pathways and their moons such as Titan. Subject headinggs: astrochemistry -- cosmic rays -- ISM: molecules -- methods- tected methane in interstellar ices via its 4 deformation mode at 7.676 m (1303 cmÀ1 ). The abundance

  2. Ice thickness measurements by Raman scattering

    E-Print Network [OSTI]

    Pershin, Sergey M; Klinkov, Vladimir K; Yulmetov, Renat N; Bunkin, Alexey F

    2014-01-01

    A compact Raman LIDAR system with a spectrograph was used for express ice thickness measurements. The difference between the Raman spectra of ice and liquid water is employed to locate the ice-water interface while elastic scattering was used for air-ice surface detection. This approach yields an error of only 2 mm for an 80-mm-thick ice sample, indicating that it is promising express noncontact thickness measurements technique in field experiments.

  3. Method and apparatus for melting glass batch

    DOE Patents [OSTI]

    Fassbender, Alexander G. (Kennewick, WA); Walkup, Paul C. (Richland, WA); Mudge, Lyle K. (Richland, WA)

    1988-01-01

    A glass melting system involving preheating, precalcining, and prefluxing of batch materials prior to injection into a glass furnace. The precursors are heated by convection rather than by radiation in present furnaces. Upon injection into the furnace, batch materials are intimately coated with molten flux so as to undergo or at least begin the process of dissolution reaction prior to entering the melt pool.

  4. High pressure melt ejection

    SciTech Connect (OSTI)

    Tarbell, W.W.; Brockmann, J.E.; Pilch, M.

    1983-01-01

    Recent probabilistic risk assessments have identified the potential for reactor pressure vessel failure while the reactor coolant system is at elevated pressure. The analyses postulate that the blowdown of steam and hydrogen into the reactor cavity will cause the core material to be swept from the cavity region into the containment building. The High Pressure Melt Streaming (HIPS) program is an experimental study of the high pressure ejection of molten material and subsequent interactions within a concrete cavity. The program focuses on using prototypic system conditions and scaled models of reactor geometries to accurately simulate the ex-vessel processes during high-pressure accident sequences. Scaling analyses of the experiment show that the criteria established for core debris removal from the cavity are met or exceeded. Tests are performed at two scales, representing 1/10th and 1/20th linear reproductions of the Zion reactor plant. Results of the 1/20th scale tests are presented.

  5. Integrated navigation for AUV operations under ice shelves

    E-Print Network [OSTI]

    Griffiths, Gwyn

    2000 Heat Wipes Out Giant Antarctic Ice Shelf The Independent, 31 January 2000 Catastrophic Melting VI Pine Island Bay #12;The (virtual) mission ... #12;The first mission- March 2003: Pine Island Bay NASA 30 km Sea Ice Pine Island Glacier Open Water 9 February 2003 #12;The Pine Island Bay Glacier

  6. Passive ice freezing-releasing heat pipe. [Patent application

    DOE Patents [OSTI]

    Gorski, A.J.; Schertz, W.W.

    1980-09-29

    A heat pipe device has been developed which permits completely passive ice formation and periodic release of ice without requiring the ambient temperature to rise above the melting point of water. This passive design enables the maximum amount of cooling capacity to be stored in the tank.

  7. Effects of glacial ice on subsurface temperatures of hydrothermal systems in Yellowstone National Park, Wyoming: Fluid-inclusion evidence

    SciTech Connect (OSTI)

    Bargar, K.E.; Fournier, R.O. (Geological Survey, Menlo Park, CA (USA))

    1988-12-01

    Hydrothermal quartz and fluorite crystals containing liquid-rich fluid inclusions (coexisting vapor-rich fluid inclusions were not observed) were found in drill cores from eight relatively shallow research holes drilled by the US Geological Survey in and near major geyser basins of Yellowstone National Park. Homogenization temperatures (T{sub h}) for mostly secondary fluid inclusions show variations in temperature that have occurred at give depths since precipitation of the host minerals. Within major hydrothermal upflow zones, fluid-inclusion T{sub h} values all were found to be equal to or higher (commonly 20-50 C and up to 155 C higher) than present temperatures at the depths sampled. During periods when thick glacial ice covered the Yellowstone National Park region, pore-fluid pressures in the underlying rock were increased in proportion to the weight of the overlying column of ice. Accordingly, theoretical reference boiling-point curves that reflect the maximum temperature attainable in a hot-water geothermal system at a given depth were elevated, and temperatures within zones of major hydrothermal upflow (drill holes Y-2, Y-3, Y-6, Y-11, Y-13, and upper part of Y-5) increased. The thicknesses of ice required to elevate boiling-point curves sufficiently to account for the observed fluid-inclusion T{sub h} values are within the ranges estimated by glacial geologic studies. At the margins of major hydrothermal upflow zones (drill holes Y-4 and Y-9), fluid-inclusion T{sub h} values at given depths range from 57 C lower to about the same as the current temperature measurements because of a previous decrease in the rate of discharge of warm water and/or an increase in the rate of recharge of cold water into the hydrothermal system.

  8. Interstellar Ices

    E-Print Network [OSTI]

    Boogert, A C A

    2003-01-01

    Currently ~36 different absorption bands have been detected in the infrared spectra of cold, dense interstellar and circumstellar environments. These are attributed to the vibrational transitions of ~17 different molecules frozen on dust grains. We review identification issues and summarize the techniques required to extract information on the physical and chemical evolution of these ices. Both laboratory simulations and line of sight studies are essential. Examples are given for ice bands observed toward high mass protostars, fields stars and recent work on ices in disks surrounding low mass protostars. A number of clear trends have emerged in recent years. One prominent ice component consists of an intimate mixture between H2O, CH3OH and CO2 molecules. Apparently a stable balance exists between low temperature hydrogenation and oxidation reactions on grain surfaces. In contrast, an equally prominent ice component, consisting almost entirely of CO, must have accreted directly from the gas phase. Thermal proc...

  9. Investigation of Glacial Dynamics in the Lambert Glacier-Amery Ice Shelf System (LAS) Using Remote Sensing 

    E-Print Network [OSTI]

    Chi, Zhaohui 1982-

    2012-12-10

    Numerous recent studies have documented dynamic changes in the behaviors of large marine-terminating outlet glaciers and ice streams in Greenland, the Antarctic Peninsula, and West Antarctica. However, fewer observations of outlet glaciers and ice...

  10. THE EXTENT OF PLEISTOCENE ICE CAP, GLACIAL DEPOSITS AND GLACIOKARST IN THE ALADAGLAR

    E-Print Network [OSTI]

    Zreda, Marek

    holes, ice caves, glacial melt-water streams, stone circles and girlands represent glacialTHE EXTENT OF PLEISTOCENE ICE CAP, GLACIAL DEPOSITS AND GLACIOKARST IN THE ALADAGLAR MASSIF between 1100 m and 3756 m of altitudes. Many of the glacial landforms, such as moraines and ice

  11. NOAA Technical Memorandum ERL GLERL-18 PHOTOSYNTHETICALLY ACTIVE RADIATION TRANSMITTANCE THROUGH ICE

    E-Print Network [OSTI]

    to obtain the ratios shown in Figure 9. 9. Ratio of under-ice to above-ice radiation (T) versus true solar. 12. Ratio of below- to above-ice radiation (T) as a function of true solar time (TST) during a period of melting snow for 7 March 1977. 13. Radiation transmittance (T) as a function of true solar time (TST

  12. Tightly integrated single- and multi-crystal data collection strategy calculation and parallelized data processing in JBluIce beamline control system

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

    Pothineni, Sudhir Babu; Venugopalan, Nagarajan; Ogata, Craig M.; Hilgart, Mark C.; Stepanov, Sergey; Sanishvili, Ruslan; Becker, Michael; Winter, Graeme; Sauter, Nicholas K.; Smith, Janet L.; et al

    2014-11-18

    The calculation of single- and multi-crystal data collection strategies and a data processing pipeline have been tightly integrated into the macromolecular crystallographic data acquisition and beamline control software JBluIce. Both tasks employ wrapper scripts around existing crystallographic software. JBluIce executes scripts through a distributed resource management system to make efficient use of all available computing resources through parallel processing. The JBluIce single-crystal data collection strategy feature uses a choice of strategy programs to help users rank sample crystals and collect data. The strategy results can be conveniently exported to a data collection run. The JBluIce multi-crystal strategy feature calculates amore »collection strategy to optimize coverage of reciprocal space in cases where incomplete data are available from previous samples. The JBluIce data processing runs simultaneously with data collection using a choice of data reduction wrappers for integration and scaling of newly collected data, with an option for merging with pre-existing data. Data are processed separately if collected from multiple sites on a crystal or from multiple crystals, then scaled and merged. Results from all strategy and processing calculations are displayed in relevant tabs of JBluIce.« less

  13. Tightly integrated single- and multi-crystal data collection strategy calculation and parallelized data processing in JBluIce beamline control system

    SciTech Connect (OSTI)

    Pothineni, Sudhir Babu; Venugopalan, Nagarajan; Ogata, Craig M.; Hilgart, Mark C.; Stepanov, Sergey; Sanishvili, Ruslan; Becker, Michael; Winter, Graeme; Sauter, Nicholas K.; Smith, Janet L.; Fischetti, Robert F.

    2014-11-18

    The calculation of single- and multi-crystal data collection strategies and a data processing pipeline have been tightly integrated into the macromolecular crystallographic data acquisition and beamline control software JBluIce. Both tasks employ wrapper scripts around existing crystallographic software. JBluIce executes scripts through a distributed resource management system to make efficient use of all available computing resources through parallel processing. The JBluIce single-crystal data collection strategy feature uses a choice of strategy programs to help users rank sample crystals and collect data. The strategy results can be conveniently exported to a data collection run. The JBluIce multi-crystal strategy feature calculates a collection strategy to optimize coverage of reciprocal space in cases where incomplete data are available from previous samples. The JBluIce data processing runs simultaneously with data collection using a choice of data reduction wrappers for integration and scaling of newly collected data, with an option for merging with pre-existing data. Data are processed separately if collected from multiple sites on a crystal or from multiple crystals, then scaled and merged. Results from all strategy and processing calculations are displayed in relevant tabs of JBluIce.

  14. Rubber friction on ice and snow surfaces 

    E-Print Network [OSTI]

    Skouvaklis, Gerasimos

    2011-06-28

    The friction of rubber on ice and snow surfaces is complex. Deeper scientific understanding is important for optimising performance of tyres in winter. Rubber, ice and snow systems exhibit frictional behaviour which ...

  15. Melt containment member

    DOE Patents [OSTI]

    Rieken, Joel R.; Heidloff, Andrew J.

    2014-09-09

    A tubular melt containment member for transient containment of molten metals and alloys, especially reactive metals and alloys, includes a melt-contacting layer or region that comprises an oxygen-deficient rare earth oxide material that is less reactive as compared to the counterpart stoichiometric rare earth oxide. The oxygen-deficient (sub-stoichiometric) rare earth oxide can comprise oxygen-deficient yttria represented by Y.sub.2O.sub.3-x wherein x is from 0.01 to 0.1. Use of the oxygen-deficient rare earth oxide as the melt-contacting layer or region material reduces reaction with the melt for a given melt temperature and melt contact time.

  16. A view of treatment process of melted nuclear fuel on a severe accident plant using a molten salt system

    SciTech Connect (OSTI)

    Fujita, R.; Takahashi, Y.; Nakamura, H.; Mizuguchi, K. [Power and Industrial Research and Development Center, Toshiba Corporation Power Systems Company, 4-1 Ukishima-cho, Kawasaki-ku, Kawasaki 210-0862 (Japan); Oomori, T. [Chemical System Design and Engineering Department, Toshiba Corporation Power Systems Company, 8 Shinsugita-cho, Isogo-ku, Yokohama 235-8523 (Japan)

    2013-07-01

    At severe accident such as Fukushima Daiichi Nuclear Power Plant Accident, the nuclear fuels in the reactor would melt and form debris which contains stable UO2-ZrO2 mixture corium and parts of vessel such as zircaloy and iron component. The requirements for solution of issues are below; -) the reasonable treatment process of the debris should be simple and in-situ in Fukushima Daiichi power plant, -) the desirable treatment process is to take out UO{sub 2} and PuO{sub 2} or metallic U and TRU metal, and dispose other fission products as high level radioactive waste; and -) the candidate of treatment process should generate the smallest secondary waste. Pyro-process has advantages to treat the debris because of the high solubility of the debris and its total process feasibility. Toshiba proposes a new pyro-process in molten salts using electrolysing Zr before debris fuel being treated.

  17. High-Resolution Monitoring of Internal Layers Over the Greenland Ice Sheet P. Kanagaratnam, S.P. Gogineni

    E-Print Network [OSTI]

    Kansas, University of

    been attributed to the melting of mountain glaciers among other causes. The mass balance of the glacial attributed half of this rise to thermal expansion of the ocean and melting of mountain glaciers. To assess extent, intensity of summer melt, wind-generated surface roughness, ice temperature, and absolute

  18. Iced Coffee Iced Yerba Mate "Tea"

    E-Print Network [OSTI]

    Iced Coffee Iced Yerba Mate "Tea" Iced Yerba Mate Latte Iced Chai Tea Latte Original, Green Tea Canned Soda Xing Tea Bottled Water Arizona Teas Energy Drinks Red Bull, SF Red Bull & Bing Jones Sodas $0 Cafe au Lait Hot Tea Yerba Mate "Tea" Yerba Mate Latte Chai Tea Latte - Original, Green Tea, or Sugar

  19. Diffusive over-hydration of olivine-hosted melt inclusions

    E-Print Network [OSTI]

    Hartley, Margaret E.; Neave, David A.; Maclennan, John; Edmonds, Marie; Thordarson, Thor

    2015-06-11

    to co m fic en is Zh er an te Ce pi en se pr th at th pr pr W ou close to their centres as possible (which reduces the likelihood of mpositions into magma reservoirs where crystallisation is oc- rring (Maclennan, 2008; Rudge et al., 2013). Mixing... primary melts In order to assess the extent of diffusive re-equilibration in the Z inclusions, H2O/Ce must be determined for undegassed melts. olatile saturation models indicate that the Skuggafjöll magma upted under ice/water pressures of ?1.4 MPa...

  20. Seasat, ERS-112 and NSCAT Scatterometer Observed Changes on the Large Ice Sheets

    E-Print Network [OSTI]

    Long, David G.

    scattering characteristics and regional melting delineation. SASS-NSCAT differences show 18 year changes but is switched off during SAR-mode operation. Over glacial ice, o"(dB)is approximately a linear function of 8in

  1. Relationships between Water Wettability and Ice Adhesion

    E-Print Network [OSTI]

    Meuler, Adam J.

    Ice formation and accretion may hinder the operation of many systems critical to national infrastructure, including airplanes, power lines, windmills, ships, and telecommunications equipment. Yet despite the pervasiveness ...

  2. Outgassing of icy bodies in the solar system - I. The sublimation of hexagonal water ice through dust layers

    E-Print Network [OSTI]

    Gundlach, Bastian; Blum, Jürgen

    2011-01-01

    Our knowledge about the physical processes determining the activity of comets were mainly influenced by several extremely successful space missions, the predictions of theoretical models and the results of laboratory experiments. However, novel computer models should not be treated in isolation but should be based on experimental results. Therefore, a new experimental setup was constructed to investigate the temperature dependent sublimation properties of hexagonal water ice and the gas diffusion through a dry dust layer covering the ice surface. We show that this experimental setup is capable to reproduce known gas production rates of pure hexagonal water ice. The reduction of the gas production rate due to an additional dust layer on top of the ice surface was measured and compared with the results of another experimental setup in which the gas diffusion through dust layers at room temperature was investigated. We found that the relative permeability of the dust layer is inversely proportional to its thickn...

  3. Sedimentation profiles of systems with reentrant melting behavior J. Dzubiella,* H. M. Harreis, C. N. Likos, and H. Lowen

    E-Print Network [OSTI]

    Dzubiella, Joachim

    Colloidal particles in a suspension under gravitational in- fluence show spatial inhomogeneities due to extract the hard-sphere equation of state experimentally by investigating sterically stabilized colloids 4 examine sedimentation density profiles of star polymer solutions as an example of colloidal systems

  4. Retrograde Melting and Internal Liquid Gettering in Silicon

    SciTech Connect (OSTI)

    Hudelson, Steve; Newman, Bonna K.; Bernardis, Sarah; Fenning, David P.; Bertoni, Mariana I.; Marcus, Matthew A.; Fakra, Sirine C.; Lai, Barry; Buonassisi, Tonio

    2011-07-01

    Retrograde melting (melting upon cooling) is observed in silicon doped with 3d transition metals, via synchrotron-based temperature-dependent X-ray microprobe measurements. Liquid metal-silicon droplets formed via retrograde melting act as efficient sinks for metal impurities dissolved within the silicon matrix. Cooling results in decomposition of the homogeneous liquid phase into solid multiple-metal alloy precipitates. These phenomena represent a novel pathway for engineering impurities in semiconductor-based systems.

  5. Ocean Challenge, Vol.19, Autumn 2012 Early Online The shrinking Greenland ice Sheet

    E-Print Network [OSTI]

    Johnson, Helen

    , the circulation within Greenland's fjords is not well known, and the interaction between glacial ice and the ocean's melting demands that oceanographers get involved! Unlike Antarctica, Greenland is not surrounded speeding up of the glacial ice flux over land. This in turn has caused concern over the vulnerability

  6. ARM - Lesson Plans: When Floating Ice Melts in the Sea

    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 Home Room News PublicationsClimatePastThe PacificWeather

  7. Integrated Ice Storage/Sprinkler HVAC System Sharply Cuts Energy Costs and Air-Distribution First Costs 

    E-Print Network [OSTI]

    Meckler, G.

    1986-01-01

    by distributing a small quantity (0.1 to 0.2 cfm/sq ft) of very dry, 40°F primary air. All dehumidification is handled by the ice-chilled primary air, which is distributed in variable, volume, determined by the space dehumidification requirement, to fan-coil...

  8. Scrap uranium recycling via electron beam melting

    SciTech Connect (OSTI)

    McKoon, R.

    1993-11-01

    A program is underway at the Lawrence Livermore National Laboratory (LLNL) to recycle scrap uranium metal. Currently, much of the material from forging and machining processes is considered radioactive waste and is disposed of by oxidation and encapsulation at significant cost. In the recycling process, uranium and uranium alloys in various forms will be processed by electron beam melting and continuously cast into ingots meeting applicable specifications for virgin material. Existing vacuum processing facilities at LLNL are in compliance with all current federal and state environmental, safety and health regulations for the electron beam melting and vaporization of uranium metal. One of these facilities has been retrofitted with an auxiliary electron beam gun system, water-cooled hearth, crucible and ingot puller to create an electron beam melt furnace. In this furnace, basic process R&D on uranium recycling will be performed with the goal of eventual transfer of this technology to a production facility.

  9. Community Ice Sheet Model (CISM2) Development and Marine Ice...

    Office of Scientific and Technical Information (OSTI)

    Conference: Community Ice Sheet Model (CISM2) Development and Marine Ice Sheet Simulations Citation Details In-Document Search Title: Community Ice Sheet Model (CISM2) Development...

  10. Arctic ice islands

    SciTech Connect (OSTI)

    Sackinger, W.M.; Jeffries, M.O.; Lu, M.C.; Li, F.C.

    1988-01-01

    The development of offshore oil and gas resources in the Arctic waters of Alaska requires offshore structures which successfully resist the lateral forces due to moving, drifting ice. Ice islands are floating, a tabular icebergs, up to 60 meters thick, of solid ice throughout their thickness. The ice islands are thus regarded as the strongest ice features in the Arctic; fixed offshore structures which can directly withstand the impact of ice islands are possible but in some locations may be so expensive as to make oilfield development uneconomic. The resolution of the ice island problem requires two research steps: (1) calculation of the probability of interaction between an ice island and an offshore structure in a given region; and (2) if the probability if sufficiently large, then the study of possible interactions between ice island and structure, to discover mitigative measures to deal with the moving ice island. The ice island research conducted during the 1983-1988 interval, which is summarized in this report, was concerned with the first step. Monte Carlo simulations of ice island generation and movement suggest that ice island lifetimes range from 0 to 70 years, and that 85% of the lifetimes are less then 35 years. The simulation shows a mean value of 18 ice islands present at any time in the Arctic Ocean, with a 90% probability of less than 30 ice islands. At this time, approximately 34 ice islands are known, from observations, to exist in the Arctic Ocean, not including the 10-meter thick class of ice islands. Return interval plots from the simulation show that coastal zones of the Beaufort and Chukchi Seas, already leased for oil development, have ice island recurrences of 10 to 100 years. This implies that the ice island hazard must be considered thoroughly, and appropriate safety measures adopted, when offshore oil production plans are formulated for the Alaskan Arctic offshore. 132 refs., 161 figs., 17 tabs.

  11. Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming

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

    de la Peña, S.; Howat, I. M.; Nienow, P. W.; van den Broeke, M. R.; Mosley-Thompson, E.; Price, S. F.; Mair, D.; Noël, B.; Sole, A. J.

    2015-06-11

    Atmospheric warming over the Greenland Ice Sheet during the last 2 decades has increased the amount of surface meltwater production, resulting in the migration of melt and percolation regimes to higher altitudes and an increase in the amount of ice content from refrozen meltwater found in the firn above the superimposed ice zone. Here we present field and airborne radar observations of buried ice layers within the near-surface (0–20 m) firn in western Greenland, obtained from campaigns between 1998 and 2014. We find a sharp increase in firn-ice content in the form of thick widespread layers in the percolation zone,more »which decreases the capacity of the firn to store meltwater. The estimated total annual ice content retained in the near-surface firn in areas with positive surface mass balance west of the ice divide in Greenland reached a maximum of 74 ± 25 Gt in 2012, compared to the 1958–1999 average of 13 ± 2 Gt, while the percolation zone area more than doubled between 2003 and 2012. Increased melt and column densification resulted in surface lowering averaging –0.80 ± 0.39 m yr?¹ between 1800 and 2800 m in the accumulation zone of western Greenland. Since 2007, modeled annual melt and refreezing rates in the percolation zone at elevations below 2100 m surpass the annual snowfall from the previous year, implying that mass gain in the region is retained after melt in the form of refrozen meltwater. If current melt trends over high elevation regions continue, subsequent changes in firn structure will have implications for the hydrology of the ice sheet and related abrupt seasonal densification could become increasingly significant for altimetry-derived ice sheet mass balance estimates.« less

  12. Europa: Tidal heating of upwelling thermal plumes and the origin of lenticulae and chaos melting

    E-Print Network [OSTI]

    Head III, James William

    ; Pappalardo and Head, 2001], and 3) a seafloor plume model in which tidal energy focused in the silicate ice in the shallow crust of Europa. We show that tidal energy can be preferentially focused in risingEuropa: Tidal heating of upwelling thermal plumes and the origin of lenticulae and chaos melting

  13. Quantitative estimates of velocity sensitivity to surface melt variations at a large Greenland outlet glacier

    E-Print Network [OSTI]

    Anderson, M. L.; Nettles, M.; Larsen, T. B.; Hamilton, Gordon S.; Stearns, Leigh

    2011-09-01

    , marine-terminating outlet glaciers that drain the ice sheet. We use a validated model of meltwater input and GPS-derived surface velocities to quantify the sensitivity of glacier flow speed to changes in surface melt at Helheim Glacier during two summer...

  14. Did changes in the Subpolar North Atlantic trigger the recent mass loss from the Greenland Ice Sheet?

    E-Print Network [OSTI]

    Straneo, Fiamma

    . The loss was not so much a result of increased surface melt but, rather, of ice loss due to the widespread; Holland et al. 2008]. Specifically, increased melting due, for example, to warming ocean waters can speed that STW penetrate inside Greenland's glacial fjords is limited to a handful of summer profiles from

  15. Development of a Mobile Ice Nucleus Counter

    SciTech Connect (OSTI)

    Kok, Gregory; Kulkarni, Gourihar

    2014-07-10

    An ice nucleus counter has been constructed. The instrument uses built-in refrigeration systems for wall cooling. A cascade refrigeration system will allow the cold wall to operate as low as -70 deg C, and a single stage system can operate the warm wall at -45 deg C. A unique optical particle counter has been constructed using polarization detection of the scattered light. This allows differentiation of the particles exiting the chamber to determine if they are ice or liquid.

  16. Neglecting ice-atmosphere interactions underestimates ice sheet melt in millennial-scale deglaciation simulations

    E-Print Network [OSTI]

    Pritchard, M. S.; Bush, A. B.; Marshall, S. J.

    2008-01-01

    Pergamon Press, New York. Peltier, W. R. (1985), The LAGEOSWu, P. , and W. R. Peltier (1982), Viscous gravitationalmodel based on Wu and Peltier [1982] and Peltier [1985]. A

  17. 'Like cupcakes melting in the sun...' /

    E-Print Network [OSTI]

    Skaller, Philip Emmanuel; Skaller, Philip Emmanuel.

    2014-01-01

    cupcakes melting in the sun’ A Dissertation submitted incupcakes melting in the sun’ by Philip Emmanuel SkallerLike cupcakes melting in the sun ’ was a performance of 7

  18. Ferritic steel melt and FLiBe/steel experiment : melting ferritic steel.

    SciTech Connect (OSTI)

    Troncosa, Kenneth P.; Smith, Brandon M.; Tanaka, Tina Joan

    2004-11-01

    In preparation for developing a Z-pinch IFE power plant, the interaction of ferritic steel with the coolant, FLiBe, must be explored. Sandia National Laboratories Fusion Technology Department was asked to drop molten ferritic steel and FLiBe in a vacuum system and determine the gas byproducts and ability to recycle the steel. We tried various methods of resistive heating of ferritic steel using available power supplies and easily obtained heaters. Although we could melt the steel, we could not cause a drop to fall. This report describes the various experiments that were performed and includes some suggestions and materials needed to be successful. Although the steel was easily melted, it was not possible to drip the molten steel into a FLiBe pool Levitation melting of the drop is likely to be more successful.

  19. Largest Ice-Bank Promotes Load Management 

    E-Print Network [OSTI]

    Brarmann, G. L.

    1983-01-01

    conservation measures were incorporated in the design of the new research facility, the ice-bank system has been the most cost-effective of the load management projects at Union Oil....

  20. Glaciers and Ice Sheets Mapping Orbiter concept

    E-Print Network [OSTI]

    Jezek, Kenneth; Rodriguez, Ernesto; Gogineni, Sivaprasad; Freeman, Anthony; Curlander, John; Paden, John D.; Allen, Christopher Thomas

    2006-05-13

    We describe a concept for a spaceborne radar system designed to measure the surface and basal topography of terrestrial ice sheets and to determine the physical properties of the glacier bed. Our primary objective is to ...

  1. optimal initial conditions for coupling ice sheet models to earth...

    Office of Scientific and Technical Information (OSTI)

    optimal initial conditions for coupling ice sheet models to earth system models Perego, Mauro Sandia National Laboratories Sandia National Laboratories; Price, Stephen F. Dr...

  2. optimal initial conditions for coupling ice sheet models to earth...

    Office of Scientific and Technical Information (OSTI)

    for coupling ice sheet models to earth system models Authors: Perego, Mauro 1 ; Price, Stephen F. Dr 2 ; Stadler, Georg 3 + Show Author Affiliations Sandia National...

  3. Specific heat in two-dimensional melting

    E-Print Network [OSTI]

    Sven Deutschländer; Antonio M. Puertas; Georg Maret; Peter Keim

    2014-05-14

    We report the specific heat $c_N$ around the melting transition(s) of micrometer-sized superparamagnetic particles confined in two dimensions, calculated from fluctuations of positions and internal energy, and corresponding Monte Carlo simulations. Since colloidal systems provide single particle resolution, they offer the unique possibility to compare the experimental temperatures of peak position of $c_N(T)$ and symmetry breaking, respectively. While order parameter correlation functions confirm the Kosterlitz-Thouless-Halperin-Nelson-Young melting scenario where translational and orientational order symmetries are broken at different temperatures with an intermediate so called hexatic phase, we observe a single peak of the specific heat within the hexatic phase, with excellent agreement between experiment and simulation. Thus, the peak is not associated with broken symmetries but can be explained with the total defect density, which correlates with the maximum increase of isolated dislocations. The absence of a latent heat strongly supports the continuous character of both transitions.

  4. Parameterizing Size Distribution in Ice Clouds

    SciTech Connect (OSTI)

    DeSlover, Daniel; Mitchell, David L.

    2009-09-25

    PARAMETERIZING SIZE DISTRIBUTIONS IN ICE CLOUDS David L. Mitchell and Daniel H. DeSlover ABSTRACT An outstanding problem that contributes considerable uncertainty to Global Climate Model (GCM) predictions of future climate is the characterization of ice particle sizes in cirrus clouds. Recent parameterizations of ice cloud effective diameter differ by a factor of three, which, for overcast conditions, often translate to changes in outgoing longwave radiation (OLR) of 55 W m-2 or more. Much of this uncertainty in cirrus particle sizes is related to the problem of ice particle shattering during in situ sampling of the ice particle size distribution (PSD). Ice particles often shatter into many smaller ice fragments upon collision with the rim of the probe inlet tube. These small ice artifacts are counted as real ice crystals, resulting in anomalously high concentrations of small ice crystals (D < 100 µm) and underestimates of the mean and effective size of the PSD. Half of the cirrus cloud optical depth calculated from these in situ measurements can be due to this shattering phenomenon. Another challenge is the determination of ice and liquid water amounts in mixed phase clouds. Mixed phase clouds in the Arctic contain mostly liquid water, and the presence of ice is important for determining their lifecycle. Colder high clouds between -20 and -36 oC may also be mixed phase but in this case their condensate is mostly ice with low levels of liquid water. Rather than affecting their lifecycle, the presence of liquid dramatically affects the cloud optical properties, which affects cloud-climate feedback processes in GCMs. This project has made advancements in solving both of these problems. Regarding the first problem, PSD in ice clouds are uncertain due to the inability to reliably measure the concentrations of the smallest crystals (D < 100 µm), known as the “small mode”. Rather than using in situ probe measurements aboard aircraft, we employed a treatment of ice cloud optical properties formulated in terms of PSD parameters in combination with remote measurements of thermal radiances to characterize the small mode. This is possible since the absorption efficiency (Qabs) of small mode crystals is larger at 12 µm wavelength relative to 11 µm wavelength due to the process of wave resonance or photon tunneling more active at 12 µm. This makes the 12/11 µm absorption optical depth ratio (or equivalently the 12/11 µm Qabs ratio) a means for detecting the relative concentration of small ice particles in cirrus. Using this principle, this project tested and developed PSD schemes that can help characterize cirrus clouds at each of the three ARM sites: SGP, NSA and TWP. This was the main effort of this project. These PSD schemes and ice sedimentation velocities predicted from them have been used to test the new cirrus microphysics parameterization in the GCM known as the Community Climate Systems Model (CCSM) as part of an ongoing collaboration with NCAR. Regarding the second problem, we developed and did preliminary testing on a passive thermal method for retrieving the total water path (TWP) of Arctic mixed phase clouds where TWPs are often in the range of 20 to 130 g m-2 (difficult for microwave radiometers to accurately measure). We also developed a new radar method for retrieving the cloud ice water content (IWC), which can be vertically integrated to yield the ice water path (IWP). These techniques were combined to determine the IWP and liquid water path (LWP) in Arctic clouds, and hence the fraction of ice and liquid water. We have tested this approach using a case study from the ARM field campaign called M-PACE (Mixed-Phase Arctic Cloud Experiment). This research led to a new satellite remote sensing method that appears promising for detecting low levels of liquid water in high clouds typically between -20 and -36 oC. We hope to develop this method in future research.

  5. FAFCO Ice Storage test report

    SciTech Connect (OSTI)

    Stovall, T.K.

    1993-11-01

    The Ice Storage Test Facility (ISTF) is designed to test commercial ice storage systems. FAFCO provided a storage tank equipped with coils designed for use with a secondary fluid system. The FAFCO ice storage system was tested over a wide range of operating conditions. Measured system performance during charging showed the ability to freeze the tank fully, storing from 150 to 200 ton-h. However, the charging rate showed significant variations during the latter portion of the charge cycle. During discharge cycles, the storage tank outlet temperature was strongly affected by the discharge rate and tank state of charge. The discharge capacity was dependent upon both the selected discharge rate and maximum allowable tank outlet temperature. Based on these tests, storage tank selection must depend on both charge and discharge conditions. This report describes FAFCO system performance fully under both charging and discharging conditions. While the test results reported here are accurate for the prototype 1990 FAFCO Model 200, currently available FAFCO models incorporate significant design enhancements beyond the Model 200. At least one major modification was instituted as a direct result of the ISTF tests. Such design improvements were one of EPRI`s primary goals in founding the ISTF.

  6. Global Simulations of Ice nucleation and Ice Supersaturation...

    Office of Scientific and Technical Information (OSTI)

    Article: Global Simulations of Ice nucleation and Ice Supersaturation with an Improved Cloud Scheme in the Community Atmosphere Model Citation Details In-Document Search Title:...

  7. Effects of volatiles on melt production and reactive flow in the mantle

    E-Print Network [OSTI]

    Keller, Tobias

    2015-01-01

    Magmatism in the Earth interior has a significant impact on its dynamic, thermal and compositional evolution. Experimental studies of petrology of mantle melting find that small concentrations of water and carbon dioxide have a significant effect on the solidus temperature and distribution of melting in the upper mantle. However, it has remained unclear what effect small fractions of deep, volatile-rich melts have on melting and melt transport in the shallow asthenosphere. We present a method to simulate the thermochemical evolution of the upper mantle in the presence of volatiles. The method is based on a novel, thermodynamically consistent framework for reactive, disequilibrium, multi-component melting/crystallisation. This is coupled with a system of equations representing conservation of mass, momentum, and energy for a partially molten grain aggregate. Application of this method to upwelling-column models demonstrates that it captures leading-order features of hydrated and carbonated peridotite melting. ...

  8. Topological Constraints in Directed Polymer Melts

    E-Print Network [OSTI]

    Serna, Pablo; Nahum, Adam

    2015-01-01

    Polymers in a melt may be subject to topological constraints, as in the example of unlinked polymer rings. How to do statistical mechanics in the presence of such constraints remains a fundamental open problem. We study the effect of topological constraints on a melt of directed polymers using simulations of a simple quasi-2D model. We find that fixing the global topology of the melt to be trivial changes the polymer conformations drastically. Polymers of length $L$ wander in the transverse direction only by a distance of order $(\\ln L)^\\zeta$ with $\\zeta \\simeq 1.5$. This is strongly suppressed in comparison with the Brownian scaling $L^{1/2}$ which holds in the absence of the topological constraint. It is also much less than the prediction $L^{1/4}$ of a mean-field-like `array of obstacles' model: thus we rule out such a model in the present setting. Dynamics are also strongly affected by the constraints, and a tagged monomer in an infinite system performs logarithmically slow subdiffusion. To cast light on...

  9. Development, sensitivity analysis, and uncertainty quantification of high-fidelity arctic sea ice models.

    SciTech Connect (OSTI)

    Peterson, Kara J.; Bochev, Pavel Blagoveston; Paskaleva, Biliana S.

    2010-09-01

    Arctic sea ice is an important component of the global climate system and due to feedback effects the Arctic ice cover is changing rapidly. Predictive mathematical models are of paramount importance for accurate estimates of the future ice trajectory. However, the sea ice components of Global Climate Models (GCMs) vary significantly in their prediction of the future state of Arctic sea ice and have generally underestimated the rate of decline in minimum sea ice extent seen over the past thirty years. One of the contributing factors to this variability is the sensitivity of the sea ice to model physical parameters. A new sea ice model that has the potential to improve sea ice predictions incorporates an anisotropic elastic-decohesive rheology and dynamics solved using the material-point method (MPM), which combines Lagrangian particles for advection with a background grid for gradient computations. We evaluate the variability of the Los Alamos National Laboratory CICE code and the MPM sea ice code for a single year simulation of the Arctic basin using consistent ocean and atmospheric forcing. Sensitivities of ice volume, ice area, ice extent, root mean square (RMS) ice speed, central Arctic ice thickness, and central Arctic ice speed with respect to ten different dynamic and thermodynamic parameters are evaluated both individually and in combination using the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA). We find similar responses for the two codes and some interesting seasonal variability in the strength of the parameters on the solution.

  10. Focused synthetic aperture radar processing of ice-sounder data collected over the Greenland ice sheet

    E-Print Network [OSTI]

    Legarsky, J.; Gogineni, Sivaprasad; Akins, T. L.

    2001-10-01

    We developed a synthetic aperture radar (SAR) processing algorithm for airborne/spaceborne ice-sounding radar systems and applied it to data collected in Greenland. By using focused SAR (phase-corrected coherent averaging), we improved along...

  11. JOURNAL OF GEOPHYSICAL RESEARCH, VOL 104, NO C7, PAGES 15,66915,677, JULY 15, 1999 An energyconserving thermodynamic model of sea ice

    E-Print Network [OSTI]

    Bitz, Cecilia

    of internal brine­pocket melting on surface ablation. Sea ice models that parameterize latent heat storage season. Compared with our energy­conserving model, a nonconserving model underestimates top to brine pockets, which change size in order to remain in thermal equilibrium with the ice [Schwerdtfeger

  12. THE STRUCTURE OF SURFACE H{sub 2}O LAYERS OF ICE-COVERED PLANETS WITH HIGH-PRESSURE ICE

    SciTech Connect (OSTI)

    Ueta, S.; Sasaki, T. E-mail: takanori@geo.titech.ac.jp

    2013-10-01

    Many extrasolar (bound) terrestrial planets and free-floating (unbound) planets have been discovered. While the existence of bound and unbound terrestrial planets with liquid water is an important question, of particular importance is the question of these planets' habitability. Even for a globally ice-covered planet, geothermal heat from the planetary interior may melt the interior ice, creating an internal ocean covered by an ice shell. In this paper, we discuss the conditions that terrestrial planets must satisfy for such an internal ocean to exist on the timescale of planetary evolution. The question is addressed in terms of planetary mass, distance from a central star, water abundance, and abundance of radiogenic heat sources. In addition, we investigate the structure of the surface H{sub 2}O layers of ice-covered planets by considering the effects of ice under high pressure (high-pressure ice). As a fiducial case, a 1 M{sub ?} planet at 1 AU from its central star and with 0.6-25 times the H{sub 2}O mass of the Earth could have an internal ocean. We find that high-pressure ice layers may appear between the internal ocean and the rock portion on a planet with an H{sub 2}O mass over 25 times that of the Earth. The planetary mass and abundance of surface water strongly restrict the conditions under which an extrasolar terrestrial planet may have an internal ocean with no high-pressure ice under the ocean. Such high-pressure ice layers underlying the internal ocean are likely to affect the habitability of the planet.

  13. Long-term ice sheetclimate interactions under anthropogenic greenhouse forcing simulated with a complex Earth System Model

    E-Print Network [OSTI]

    Winguth, Arne

    with a complex Earth System Model Miren Vizcai´no Æ Uwe Mikolajewicz Æ Matthias Gro¨ger Æ Ernst Maier-Reimer Æ-millennia simulations have been performed with a complex Earth System Model (ESM) for different anthropogenic climate climate change Á Meridional overturning circulation Á Earth system modelling Á Sea level 1 Introduction

  14. Anisotropic Interfacial Free Energies of the Hard-Sphere Crystal-Melt Interfaces Yan Mu, Andrew Houk, and Xueyu Song*

    E-Print Network [OSTI]

    Song, Xueyu

    Anisotropic Interfacial Free Energies of the Hard-Sphere Crystal-Melt Interfaces Yan Mu, Andrew-melt interfacial free energy calculations using capillary wave approach. Using this method, we have calculated the free energies of the fcc crystal-melt interfaces for the hard-sphere system as a function of crystal

  15. Drilling deep in South Pole Ice

    E-Print Network [OSTI]

    Karg, Timo

    2014-01-01

    To detect the tiny flux of ultra-high energy neutrinos from active galactic nuclei or from interactions of highest energy cosmic rays with the microwave background photons needs target masses of the order of several hundred cubic kilometers. Clear Antarctic ice has been discussed as a favorable material for hybrid detection of optical, radio and acoustic signals from ultra-high energy neutrino interactions. To apply these technologies at the adequate scale hundreds of holes have to be drilled in the ice down to depths of about 2500 m to deploy the corresponding sensors. To do this on a reasonable time scale is impossible with presently available tools. Remote drilling and deployment schemes have to be developed to make such a detector design reality. After a short discussion of the status of modern hot water drilling we present here a design of an autonomous melting probe, tested 50 years ago to reach a depth of about 1000 m in Greenland ice. A scenario how to build such a probe today with modern technologies...

  16. Curvature fluctuations and the Lyapunov exponent at melting

    SciTech Connect (OSTI)

    Mehra, V.; Ramaswamy, R. [School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067 (India)] [School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067 (India)

    1997-09-01

    We calculate the maximal Lyapunov exponent in constant-energy molecular-dynamics simulations at the melting transition for finite clusters of 6{endash}13 particles (model rare-gas and metallic systems) as well as for bulk rare-gas solids. For clusters, the Lyapunov exponent generally varies linearly with the total energy, but the {ital slope} changes sharply at the melting transition. In the bulk system, melting corresponds to a jump in the Lyapunov exponent, and this corresponds to a singularity in the variance of the curvature of the potential-energy surface. In these systems there are two mechanisms of chaos{emdash}local instability and parametric instability. We calculate the contribution of the parametric instability toward the chaoticity of these systems using a recently proposed formalism. The contribution of parametric instability is a continuous function of energy in small clusters but not in the bulk where the melting corresponds to a decrease in this quantity. This implies that the melting in small clusters does not lead to enhanced local instability. {copyright} {ital 1997} {ital The American Physical Society}

  17. Melting a granular glass by cooling

    E-Print Network [OSTI]

    Jan Plagge; Claus Heussinger

    2013-02-05

    Driven granular systems readily form glassy phases at high particle volume fractions and low driving amplitudes. We use computer simulations of a driven granular glass to evidence a re-entrance melting transition into a fluid state, which, contrary to intuition, occurs by \\emph{reducing} the amplitude of the driving. This transition is accompanied by anomalous particle dynamics and super-diffusive behavior on intermediate time-scales. We highlight the special role played by frictional interactions, which help particles to escape their glassy cages. Such an effect is in striking contrast to what friction is expected to do: reduce particle mobility by making them stick.

  18. Melting Objects M. W. Jones

    E-Print Network [OSTI]

    Jones, Mark W.

    both thermal flow and the latent heat during the phase change. The mechanism for energy transfer realistic animations of melting objects. The work presented here introduces a method that accurately models object and the method is particularly suited to rigid solids with complex surface geometry

  19. Seismicity on the western Greenland Ice Sheet: Surface fracture in the vicinity of active moulins

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

    Carmichael, Joshua D.; Joughin, Ian; Behn, Mark D.; Das, Sarah; King, Matt A.; Stevens, Laura; Lizarralde, Dan

    2015-06-25

    We analyzed geophone and GPS measurements collected within the ablation zone of the western Greenland Ice Sheet during a ~35 day period of the 2011 melt season to study changes in ice deformation before, during, and after a supraglacial lake drainage event. During rapid lake drainage, ice flow speeds increased to ~400% of winter values, and icequake activity peaked. At times >7 days after drainage, this seismicity developed variability over both diurnal and longer periods (~10 days), while coincident ice speeds fell to ~150% of winter values and showed nightly peaks in spatial variability. Approximately 95% of all detected seismicitymore »in the lake basin and its immediate vicinity was triggered by fracture propagation within near-surface ice (« less

  20. Black carbon aerosols and the third polar ice cap

    SciTech Connect (OSTI)

    Menon, Surabi; Koch, Dorothy; Beig, Gufran; Sahu, Saroj; Fasullo, John; Orlikowski, Daniel

    2010-04-15

    Recent thinning of glaciers over the Himalayas (sometimes referred to as the third polar region) have raised concern on future water supplies since these glaciers supply water to large river systems that support millions of people inhabiting the surrounding areas. Black carbon (BC) aerosols, released from incomplete combustion, have been increasingly implicated as causing large changes in the hydrology and radiative forcing over Asia and its deposition on snow is thought to increase snow melt. In India BC emissions from biofuel combustion is highly prevalent and compared to other regions, BC aerosol amounts are high. Here, we quantify the impact of BC aerosols on snow cover and precipitation from 1990 to 2010 over the Indian subcontinental region using two different BC emission inventories. New estimates indicate that Indian BC emissions from coal and biofuel are large and transport is expected to expand rapidly in coming years. We show that over the Himalayas, from 1990 to 2000, simulated snow/ice cover decreases by {approx}0.9% due to aerosols. The contribution of the enhanced Indian BC to this decline is {approx}36%, similar to that simulated for 2000 to 2010. Spatial patterns of modeled changes in snow cover and precipitation are similar to observations (from 1990 to 2000), and are mainly obtained with the newer BC estimates.

  1. Evolution of supra-glacial lakes across the Greenland Ice Sheet 

    E-Print Network [OSTI]

    Sundal, Aud

    2008-12-05

    We used 268 cloud-free Moderate-resolution Imaging Spectroradiometer (MODIS) images spanning the melt seasons 2003 and 2005-2007 to study the seasonal evolution of supra-glacial lakes in three different regions of the Greenland ice sheet. Lake area...

  2. The Ross Sea Response to Evolving Ocean-Ice Interactions in a Changing Climate 

    E-Print Network [OSTI]

    Wiederwohl, Christina 1980-

    2012-12-03

    decade (1994–2007) mostly (50%) from larger melt water inputs from the Pine Island (17.7 km^3 per decade) and Dotson (14.8 km^3 per decade) glaciers. Two decades of steady (1978-2000) strengthening of sea ice productivity (200 km^3 per decade) within...

  3. Ex-Vessel Core Melt Modeling Comparison between MELTSPREAD-CORQUENCH and MELCOR 2.1

    SciTech Connect (OSTI)

    Robb, Kevin R.; Farmer, Mitchell; Francis, Matthew W.

    2014-03-01

    System-level code analyses by both United States and international researchers predict major core melting, bottom head failure, and corium-concrete interaction for Fukushima Daiichi Unit 1 (1F1). Although system codes such as MELCOR and MAAP are capable of capturing a wide range of accident phenomena, they currently do not contain detailed models for evaluating some ex-vessel core melt behavior. However, specialized codes containing more detailed modeling are available for melt spreading such as MELTSPREAD as well as long-term molten corium-concrete interaction (MCCI) and debris coolability such as CORQUENCH. In a preceding study, Enhanced Ex-Vessel Analysis for Fukushima Daiichi Unit 1: Melt Spreading and Core-Concrete Interaction Analyses with MELTSPREAD and CORQUENCH, the MELTSPREAD-CORQUENCH codes predicted the 1F1 core melt readily cooled in contrast to predictions by MELCOR. The user community has taken notice and is in the process of updating their systems codes; specifically MAAP and MELCOR, to improve and reduce conservatism in their ex-vessel core melt models. This report investigates why the MELCOR v2.1 code, compared to the MELTSPREAD and CORQUENCH 3.03 codes, yield differing predictions of ex-vessel melt progression. To accomplish this, the differences in the treatment of the ex-vessel melt with respect to melt spreading and long-term coolability are examined. The differences in modeling approaches are summarized, and a comparison of example code predictions is provided.

  4. The role of ice nuclei recycling in the maintenance of cloud ice in Arctic mixed-phase stratocumulus

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

    Solomon, A.; Feingold, G.; Shupe, M. D.

    2015-09-25

    This study investigates the maintenance of cloud ice production in Arctic mixed-phase stratocumulus in large eddy simulations that include a prognostic ice nuclei (IN) formulation and a diurnal cycle. Balances derived from a mixed-layer model and phase analyses are used to provide insight into buffering mechanisms that maintain ice in these cloud systems. We find that, for the case under investigation, IN recycling through subcloud sublimation considerably prolongs ice production over a multi-day integration. This effective source of IN to the cloud dominates over mixing sources from above or below the cloud-driven mixed layer. Competing feedbacks between dynamical mixing andmore »recycling are found to slow the rate of ice lost from the mixed layer when a diurnal cycle is simulated. The results of this study have important implications for maintaining phase partitioning of cloud ice and liquid that determine the radiative forcing of Arctic mixed-phase clouds.« less

  5. The role of ice nuclei recycling in the maintenance of cloud ice in Arctic mixed-phase stratocumulus

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

    Solomon, A.; Feingold, G.; Shupe, M. D.

    2015-04-21

    This study investigates the maintenance of cloud ice production in Arctic mixed phase stratocumulus in large-eddy simulations that include a prognostic ice nuclei (IN) formulation and a diurnal cycle. Balances derived from a mixed-layer model and phase analyses are used to provide insight into buffering mechanisms that maintain ice in these cloud systems. We find that for the case under investigation, IN recycling through subcloud sublimation considerably prolongs ice production over a multi-day integration. This effective source of IN to the cloud dominates over mixing sources from above or below the cloud-driven mixed layer. Competing feedbacks between dynamical mixing andmore »recycling are found to slow the rate of ice lost from the mixed layer when a diurnal cycle is simulated. The results of this study have important implications for maintaining phase partitioning of cloud ice and liquid that determine the radiative forcing of Arctic mixed-phase clouds.« less

  6. Ice Bear® Storage Module | Department of Energy

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

    Ice Bear Storage Module Ice Bear Storage Module Thermal Energy Storage for Light Commercial Refrigerant-Based Air Conditioning Units The Ice Bear storage technology was...

  7. IDENTIFICATION NUMBER: 4ME20 Abstract--Artificial welding of melt-textured YBCO blocks

    E-Print Network [OSTI]

    Amoros, Jaume

    1 IDENTIFICATION NUMBER: 4ME20 Abstract--Artificial welding of melt-textured YBCO blocks opens the superconducting quality of the welds, we have developed a Hall probe mapping system, able to record the local to characterize welded samples prepared with a new Ag induced surface melting joining technique. The magnetization

  8. Evaluation of melting process of the permafrost on Mars: Its implication for surface features

    E-Print Network [OSTI]

    Manga, Michael

    . The point of our simulation is incorporation of thermal convection in porous media, which has not been in the melted zone causes drastic change in heat transfer, which results in focusing in the growth of the melt surface features around the outflow channels. INDEX TERMS: 6225 Planetology: Solar System Objects: Mars

  9. Reducing uncertainty in high-resolution sea ice models.

    SciTech Connect (OSTI)

    Peterson, Kara J.; Bochev, Pavel Blagoveston

    2013-07-01

    Arctic sea ice is an important component of the global climate system, reflecting a significant amount of solar radiation, insulating the ocean from the atmosphere and influencing ocean circulation by modifying the salinity of the upper ocean. The thickness and extent of Arctic sea ice have shown a significant decline in recent decades with implications for global climate as well as regional geopolitics. Increasing interest in exploration as well as climate feedback effects make predictive mathematical modeling of sea ice a task of tremendous practical import. Satellite data obtained over the last few decades have provided a wealth of information on sea ice motion and deformation. The data clearly show that ice deformation is focused along narrow linear features and this type of deformation is not well-represented in existing models. To improve sea ice dynamics we have incorporated an anisotropic rheology into the Los Alamos National Laboratory global sea ice model, CICE. Sensitivity analyses were performed using the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA) to determine the impact of material parameters on sea ice response functions. Two material strength parameters that exhibited the most significant impact on responses were further analyzed to evaluate their influence on quantitative comparisons between model output and data. The sensitivity analysis along with ten year model runs indicate that while the anisotropic rheology provides some benefit in velocity predictions, additional improvements are required to make this material model a viable alternative for global sea ice simulations.

  10. Quantum Hooke's Law to classify pulse laser induced ultrafast melting

    SciTech Connect (OSTI)

    Hu, Hao; Ding, Hepeng; Liu, Feng

    2015-02-03

    Ultrafast crystal-to-liquid phase transition induced by femtosecond pulse laser excitation is an interesting material's behavior manifesting the complexity of light-matter interaction. There exist two types of such phase transitions: one occurs at a time scale shorter than a picosecond via a nonthermal process mediated by electron-hole plasma formation; the other at a longer time scale via a thermal melting process mediated by electron-phonon interaction. However, it remains unclear what material would undergo which process and why? Here, by exploiting the property of quantum electronic stress (QES) governed by quantum Hooke's law, we classify the transitions by two distinct classes of materials: the faster nonthermal process can only occur in materials like ice having an anomalous phase diagram characterized with dTm/dP < 0, where Tm is the melting temperature and P is pressure, above a high threshold laser fluence; while the slower thermal process may occur in all materials. Especially, the nonthermal transition is shown to be induced by the QES, acting like a negative internal pressure, which drives the crystal into a “super pressing” state to spontaneously transform into a higher-density liquid phase. Our findings significantly advance fundamental understanding of ultrafast crystal-to-liquid phase transitions, enabling quantitative a priori predictions.

  11. Quantum Hooke's Law to classify pulse laser induced ultrafast melting

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

    Hu, Hao; Ding, Hepeng; Liu, Feng

    2015-02-03

    Ultrafast crystal-to-liquid phase transition induced by femtosecond pulse laser excitation is an interesting material's behavior manifesting the complexity of light-matter interaction. There exist two types of such phase transitions: one occurs at a time scale shorter than a picosecond via a nonthermal process mediated by electron-hole plasma formation; the other at a longer time scale via a thermal melting process mediated by electron-phonon interaction. However, it remains unclear what material would undergo which process and why? Here, by exploiting the property of quantum electronic stress (QES) governed by quantum Hooke's law, we classify the transitions by two distinct classes ofmore »materials: the faster nonthermal process can only occur in materials like ice having an anomalous phase diagram characterized with dTm/dP m is the melting temperature and P is pressure, above a high threshold laser fluence; while the slower thermal process may occur in all materials. Especially, the nonthermal transition is shown to be induced by the QES, acting like a negative internal pressure, which drives the crystal into a “super pressing” state to spontaneously transform into a higher-density liquid phase. Our findings significantly advance fundamental understanding of ultrafast crystal-to-liquid phase transitions, enabling quantitative a priori predictions.« less

  12. WATER ICE IN THE KUIPER BELT

    SciTech Connect (OSTI)

    Brown, M. E.; Fraser, W. C. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Schaller, E. L., E-mail: mbrown@caltech.edu [NASA Dryden Aircraft Operations Facility, Palmdale, CA 93550 (United States)

    2012-06-15

    We examine a large collection of low-resolution near-infrared spectra of Kuiper Belt objects (KBOs) and centaurs in an attempt to understand the presence of water ice in the Kuiper Belt. We find that water ice on the surface of these objects occurs in three separate manners: (1) Haumea family members uniquely show surfaces of nearly pure water ice, presumably a consequence of the fragmentation of the icy mantle of a larger differentiated proto-Haumea; (2) large objects with absolute magnitudes of H < 3 (and a limited number to H = 4.5) have surface coverings of water ice-perhaps mixed with ammonia-that appears to be related to possibly ancient cryovolcanism on these large objects; and (3) smaller KBOs and centaurs which are neither Haumea family members nor cold-classical KBOs appear to divide into two families (which we refer to as 'neutral' and 'red'), each of which is a mixture of a common nearly neutral component and either a slightly red or very red component that also includes water ice. A model suggesting that the difference between neutral and red objects due to formation in an early compact solar system either inside or outside, respectively, of the {approx}20 AU methanol evaporation line is supported by the observation that methanol is only detected on the reddest objects, which are those which would be expected to have the most of the methanol containing mixture.

  13. Energy conservation in ice skating rinks

    SciTech Connect (OSTI)

    Dietrich, B.K.; McAvoy, T.J.

    1980-01-01

    An economic and energy analysis of ice rinks was made to examine the areas in which energy could be profitably conserved. The areas where new equipment could make a major reduction in energy use are: the use of waste heat for space heating, the installation of a low emissivity false ceiling to reduce radiant heat, the use of a load cycling controller to reduce refrigeration costs, and the installation of more efficient lighting systems. Changes in rink operating procedure that could cut energy use are: higher refrigerant temperatures, thinner ice, the use of colder resurfacing water, turning the compressors and pumps off at night, and reducing ventilation.

  14. Energy Saving Melting and Revert Reduction Technology (E-SMARRT): Development of Surface Engineered Coating Systems for Aluminum Pressure Die Casting Dies: Towards a 'Smart' Die Coating

    SciTech Connect (OSTI)

    Dr. John J. Moore; Dr. Jianliang Lin,

    2012-07-31

    The main objective of this research program was to design and develop an optimal coating system that extends die life by minimizing premature die failure. In high-pressure aluminum die-casting, the die, core pins and inserts must withstand severe processing conditions. Many of the dies and tools in the industry are being coated to improve wear-resistance and decrease down-time for maintenance. However, thermal fatigue in metal itself can still be a major problem, especially since it often leads to catastrophic failure (i.e. die breakage) as opposed to a wear-based failure (parts begin to go out of tolerance). Tooling costs remain the largest portion of production costs for many of these parts, so the ability prevent catastrophic failures would be transformative for the manufacturing industry.The technology offers energy savings through reduced energy use in the die casting process from several factors, including increased life of the tools and dies, reuse of the dies and die components, reduction/elimination of lubricants, and reduced machine down time, and reduction of Al solder sticking on the die. The use of the optimized die coating system will also reduce environmental wastes and scrap parts. Current (2012) annual energy saving estimates, based on initial dissemination to the casting industry in 2010 and market penetration of 80% by 2020, is 3.1 trillion BTU's/year. The average annual estimate of CO2 reduction per year through 2020 is 0.63 Million Metric Tons of Carbon Equivalent (MM TCE).

  15. Third international workshop on ice storage for cooling applications

    SciTech Connect (OSTI)

    Gorski, A.J.

    1986-04-01

    The third international workshop on ice storage for cooling applications which was informal and interactive in nature, was open to persons interested in all ice-growing technologies and in ice storage, both seasonal and diurnal. Presentations were made on some 20 topics, ranging from freezers in Alaska to ice cooling of commercial jet aircraft. Workshop tours included visits to ice-storage systems at Commonwealth Edison's facilities in Bolingbrook and Des Plaines Valley, the A.C. Neilsen builing in Northbrook, and the new State of Illinois Center in Chicago. The first workshop in the present series considered the future of ice storage and predicted applications in the agricultural sector, desalinization, and commercial ice production. Progress has been rapid in the intervening two years, and an important topic at the third workshop was the possible use of ''warm ices'' (clathrate hydrates) for energy storage. This report consists primarily of abstracts of presentations made at the workshop. Persons wishing to obtain further information about particular papers should contact the speakers directly; speakers' addresses and telephone numbers are listed in this report.

  16. Detection of melting by X-ray imaging at high pressure

    SciTech Connect (OSTI)

    Li, Li; Weidner, Donald J.

    2014-06-15

    The occurrence of partial melting at elevated pressure and temperature is documented in real time through measurement of volume strain induced by a fixed temperature change. Here we present the methodology for measuring volume strains to one part in 10{sup ?4} for mm{sup 3} sized samples in situ as a function of time during a step in temperature. By calibrating the system for sample thermal expansion at temperatures lower than the solidus, the onset of melting can be detected when the melting volume increase is of comparable size to the thermal expansion induced volume change. We illustrate this technique with a peridotite sample at 1.5 GPa during partial melting. The Re capsule is imaged with a CCD camera at 20 frames/s. Temperature steps of 100 K induce volume strains that triple with melting. The analysis relies on image comparison for strain determination and the thermal inertia of the sample is clearly seen in the time history of the volume strain. Coupled with a thermodynamic model of the melting, we infer that we identify melting with 2 vol.% melting.

  17. Purification of tantalum by plasma arc melting

    DOE Patents [OSTI]

    Dunn, Paul S. (Santa Fe, NM); Korzekwa, Deniece R. (Los Alamos, NM)

    1999-01-01

    Purification of tantalum by plasma arc melting. The level of oxygen and carbon impurities in tantalum was reduced by plasma arc melting the tantalum using a flowing plasma gas generated from a gas mixture of helium and hydrogen. The flowing plasma gases of the present invention were found to be superior to other known flowing plasma gases used for this purpose.

  18. Melt dumping in string stabilized ribbon growth

    DOE Patents [OSTI]

    Sachs, Emanuel M. (42 Old Middlesex Rd., Belmont, MA 02178)

    1986-12-09

    A method and apparatus for stabilizing the edge positions of a ribbon drawn from a melt includes the use of wettable strings drawn in parallel up through the melt surface, the ribbon being grown between the strings. A furnace and various features of the crucible used therein permit continuous automatic growth of flat ribbons without close temperature control or the need for visual inspection.

  19. Modeling the impediment of methane ebullition bubbles by seasonal lake ice

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

    Greene, S.; Walter Anthony, K. M.; Archer, D.; Sepulveda-Jauregui, A.; Martinez-Cruz, K.

    2014-12-08

    Microbial methane (CH4) ebullition (bubbling) from anoxic lake sediments comprises a globally significant flux to the atmosphere, but ebullition bubbles in temperate and polar lakes can be trapped by winter ice cover and later released during spring thaw. This "ice-bubble storage" (IBS) constitutes a novel mode of CH4 emission. Before bubbles are encapsulated by downward-growing ice, some of their CH4 dissolves into the lake water, where it may be subject to oxidation. We present field characterization and a model of the annual CH4 cycle in Goldstream Lake, a thermokarst (thaw) lake in interior Alaska. We find that summertime ebullition dominatesmore »annual CH4 emissions to the atmosphere. Eighty percent of CH4 in bubbles trapped by ice dissolves into the lake water column in winter, and about half of that is oxidized. The ice growth rate and the magnitude of the CH4 ebullition flux are important controlling factors of bubble dissolution. Seven percent of annual ebullition CH4 is trapped as IBS and later emitted as ice melts. In a future warmer climate, there will likely be less seasonal ice cover, less IBS, less CH4 dissolution from trapped bubbles, and greater CH4 emissions from northern lakes.« less

  20. Modeling the impediment of methane ebullition bubbles by seasonal lake ice

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

    Greene, S.; Walter Anthony, K. M.; Archer, D.; Sepulveda-Jauregui, A.; Martinez-Cruz, K.

    2014-07-15

    Microbial methane (CH4) ebullition (bubbling) from anoxic lake sediments comprises a globally significant flux to the atmosphere, but ebullition bubbles in temperate and polar lakes can be trapped by winter ice cover and later released during spring thaw. This "ice-bubble storage" (IBS) constitutes a novel mode of CH4 emission. Before bubbles are encapsulated by downward-growing ice, some of their CH4 dissolves into the lake water, where it may be subject to oxidation. We present field characterization and a model of the annual CH4 cycle in Goldstream Lake, a thermokarst (thaw) lake in interior Alaska. We find that summertime ebullition dominatesmore »annual CH4 emissions to the atmosphere. Eighty percent of CH4 in bubbles trapped by ice dissolves into the lake water column in winter, and about half of that is oxidized. The ice growth rate and the magnitude of the CH4 ebullition flux are important controlling factors of bubble dissolution. Seven percent of annual ebullition CH4 is trapped as IBS and later emitted as ice melts. In a future warmer climate, there will likely be less seasonal ice cover, less IBS, less CH4 dissolution from trapped bubbles, and greater CH4 emissions from northern lakes.« less

  1. Nanotexturing of surfaces to reduce melting point.

    SciTech Connect (OSTI)

    Garcia, Ernest J.; Zubia, David; Mireles, Jose; Marquez, Noel; Quinones, Stella

    2011-11-01

    This investigation examined the use of nano-patterned structures on Silicon-on-Insulator (SOI) material to reduce the bulk material melting point (1414 C). It has been found that sharp-tipped and other similar structures have a propensity to move to the lower energy states of spherical structures and as a result exhibit lower melting points than the bulk material. Such a reduction of the melting point would offer a number of interesting opportunities for bonding in microsystems packaging applications. Nano patterning process capabilities were developed to create the required structures for the investigation. One of the technical challenges of the project was understanding and creating the specialized conditions required to observe the melting and reshaping phenomena. Through systematic experimentation and review of the literature these conditions were determined and used to conduct phase change experiments. Melting temperatures as low as 1030 C were observed.

  2. Hidden force floating ice

    E-Print Network [OSTI]

    Chang Q. Sun

    2015-01-17

    Because of the segmental specific-heat disparity of the hydrogen bond (O:H-O) and the Coulomb repulsion between oxygen ions, cooling elongates the O:H-O bond at freezing by stretching its containing angle and shortening the H-O bond with an association of larger O:H elongation, which makes ice less dense than water, allowing it to float.

  3. Ice Storm Supercomputer

    ScienceCinema (OSTI)

    None

    2013-05-28

    "A new Idaho National Laboratory supercomputer is helping scientists create more realistic simulations of nuclear fuel. Dubbed 'Ice Storm,' this 2048-processor machine allows researchers to model and predict the complex physics behind nuclear reactor behavior. And with a new visualization lab, the team can see the results of its simulations on the big screen." For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

  4. Low melting high lithia glass compositions and methods

    DOE Patents [OSTI]

    Jantzen, Carol M.; Pickett, John B.; Cicero-Herman, Connie A.; Marra, James C.

    2003-09-23

    The invention relates to methods of vitrifying waste and for lowering the melting point of glass forming systems by including lithia formers in the glass forming composition in significant amounts, typically from about 0.16 wt % to about 11 wt %, based on the total glass forming oxides. The lithia is typically included as a replacement for alkali oxide glass formers that would normally be present in a particular glass forming system. Replacement can occur on a mole percent or weight percent basis, and typically results in a composition wherein lithia forms about 10 wt % to about 100 wt % of the alkali oxide glass formers present in the composition. The present invention also relates to the high lithia glass compositions formed by these methods. The invention is useful for stabilization of numerous types of waste materials, including aqueous waste uranium oxides The decrease in melting point achieved by the present invention desirably prevents volatilization of hazardous or radioactive species during vitrification.

  5. Confined bilayer water melts like two highly correlated layers of Lennard-Jones particles

    E-Print Network [OSTI]

    Jon Zubeltzu; Fabiano Corsetti; M. -V. Férnandez-Serra; Emilio Artacho

    2015-10-20

    A confined bilayer of water is studied at different temperatures and densities by classical and {\\em ab initio} molecular dynamics simulations. At high density, hydrogen disorder is found to be behind the reported continuous phase transition. We observe the existence of a hexatic phase, suggesting that the Kosterlitz-Thouless-Halperin-Nelson-Young theory of a defect-mediated 2D crystal melting occurs. The liquid at different densities maintains the basic structure of the triangular ice. The two layers of liquid at high density show a strong correlation between one another without exchange of matter.

  6. Climate Impacts of Ice Nucleation

    SciTech Connect (OSTI)

    Gettelman, A.; Liu, Xiaohong; Barahona, Donifan; Lohmann, U.; Chen, Chih-Chieh

    2012-10-27

    Several different ice nucleation parameterizations in two different General Circulation Models are used to understand the effects of ice nucleation on the mean climate state, and the climate effect of aerosol perturbations to ice clouds. The simulations have different ice microphysical states that are consistent with the spread of observations. These different states occur from different parameterizations of the ice cloud nucleation processes, and feature different balances of homogeneous and heterogeneous nucleation. At reasonable efficiencies, consistent with laboratory measurements and constrained by the global radiative balance, black carbon has a small (-0.06 Wm?2) and not statistically significant climate effect. Indirect effects of anthropogenic aerosols on cirrus clouds occur mostly due to increases in homogeneous nucleation fraction as a consequence of anthropogenic sulfur emissions. The resulting ice indirect effects do not seem strongly dependent on the ice micro-physical balance, but are slightly larger for those states with less homogeneous nucleation in the base state. The total ice AIE is estimated at 0.26±0.09 Wm?2 (1? uncertainty). This represents an offset of 20-30% of the simulated total Aerosol Indirect Effect for ice and liquid clouds.

  7. ITP Metal Casting: Advanced Melting Technologies: Energy Saving...

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

    Advanced Melting Technologies: Energy Saving Concepts and Opportunities for the Metal Casting Industry ITP Metal Casting: Advanced Melting Technologies: Energy Saving Concepts and...

  8. Theory of melting at high pressures: Amending density functional theory with quantum Monte Carlo

    SciTech Connect (OSTI)

    Shulenburger, L.; Desjarlais, M. P.; Mattsson, T. R.

    2014-10-01

    We present an improved first-principles description of melting under pressure based on thermodynamic integration comparing Density Functional Theory (DFT) and quantum Monte Carlo (QMC) treatments of the system. The method is applied to address the longstanding discrepancy between density functional theory (DFT) calculations and diamond anvil cell (DAC) experiments on the melting curve of xenon, a noble gas solid where van der Waals binding is challenging for traditional DFT methods. The calculations show excellent agreement with data below 20 GPa and that the high-pressure melt curve is well described by a Lindemann behavior up to at least 80 GPa, a finding in stark contrast to DAC data.

  9. Structure order, local potentials, and physical anomalies of water ice

    E-Print Network [OSTI]

    Chang Q Sun

    2014-07-11

    Hydrogen-bond forms a pair of asymmetric, coupled, H-bridged oscillators with ultra-short-range interactions and memory. hydrogen bond cooperative relaxation and the associated binding electron entrapment and nonbonding electron polarization discriminate water and ice from other usual materials in the physical anomalies. As a strongly correlated fluctuating system, water prefers the statistically mean of tetrahedrally-coordinated structure with a supersolid skin that is elastic, polarized, ice like, hydrophobic, with 3/4 density.

  10. ARM - Ice Cores

    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? WeDatastreamstps DocumentationAtlanticENAField ParticipantsField Campaign StatisticsPastIce Cores

  11. Energy Saving Melting and Revert Reduction Technology (E-SMARRT): Melting Efficiency Improvement

    SciTech Connect (OSTI)

    Principal Investigator Kent Peaslee; Co-PI���¢��������s: Von Richards, Jeffrey Smith

    2012-07-31

    Steel foundries melt recycled scrap in electric furnaces and typically consume 35-100% excess energy from the theoretical energy requirement required to pour metal castings. This excess melting energy is multiplied by yield losses during casting and finishing operations resulting in the embodied energy in a cast product typically being three to six times the theoretical energy requirement. The purpose of this research project was to study steel foundry melting operations to understand energy use and requirements for casting operations, define variations in energy consumption, determine technologies and practices that are successful in reducing melting energy and develop new melting techniques and tools to improve the energy efficiency of melting in steel foundry operations.

  12. Therapeutic Hypothermia: Protective Cooling Using Medical Ice...

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

    Therapeutic Hypothermia: Protective Cooling Using Medical Ice Slurry Technology available for licensing: Proprietary method and equipment for making an ice slurry coolant to induce...

  13. Light propagation in the South Pole ice

    SciTech Connect (OSTI)

    Williams, Dawn; Collaboration: IceCube Collaboration

    2014-11-18

    The IceCube Neutrino Observatory is located in the ice near the geographic South Pole. Particle showers from neutrino interactions in the ice produce light which is detected by IceCube modules, and the amount and pattern of deposited light are used to reconstruct the properties of the incident neutrino. Since light is scattered and absorbed by ice between the neutrino interaction vertex and the sensor, IceCube event reconstruction depends on understanding the propagation of light through the ice. This paper presents the current status of modeling light propagation in South Pole ice, including the recent observation of an azimuthal anisotropy in the scattering.

  14. Vacuum Induction Melting Unit Induction heating is a process wherein induced eddy currents heat conductive materials. This heating

    E-Print Network [OSTI]

    Subramaniam, Anandh

    Vacuum Induction Melting Unit Induction heating is a process wherein induced eddy currents heat can be melted at a time. There are three main parts to the system: chiller, power unit and vacuum unit. The vacuum unit with rotary and diffusion pumps can attain a vacuum of 106 m bar. The power can deliver

  15. Frustration and Melting of Colloidal Molecular Crystals

    E-Print Network [OSTI]

    C. J. Olson Reichhardt; C. Reichhardt

    2002-10-14

    Using numerical simulations we show that a variety of novel colloidal crystalline states and multi-step melting phenomena occur on square and triangular two-dimensional periodic substrates. At half-integer fillings different kinds of frustration effects can be realized. A two-step melting transition can occur in which individual colloidal molecules initially rotate, destroying the overall orientational order, followed by the onset of interwell colloidal hopping, in good agreement with recent experiments.

  16. MEAT, POULTRY, Still contains ice

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    MEAT, POULTRY, SEAFOOD Still contains ice crystals and feels as cold, and ground meats Refreeze Discard Poultry and ground poultry Refreeze Discard Variety meats may safely re-freeze foods that s:ll contain ice crystals or that have been

  17. Manufacturing laser glass by continuous melting

    SciTech Connect (OSTI)

    Campbell, J H; Suratwala, T; krenitsky, S; Takeuchi, K

    2000-07-01

    A novel, continuous melting process is being used to manufacture meter-sized plates of laser glass at a rate 20-times faster, 5-times cheaper, and with 2-3 times better optical quality than with previous one-at-a-time, ''discontinuous'' technology processes. This new technology for manufacturing laser glass, which is arguably the most difficult continuously-melted optical material ever produced, comes as a result of a $60 million, six-year joint R&D program between government and industry. The glasses manufactured by the new continuous melting process are Nd-doped phosphate-based glasses and are marketed under the product names LG-770 (Schott Glass Technologies) and LHG-8 (Hoya Corporation USA). With this advance in glass manufacturing technology, it is now possible to construct high-energy, high-peak-power lasers for use in fusion energy development, national defense, and basic physics research that would have been impractical to build using the old melting technology. The development of continuously melted laser glass required technological advances that have lead to improvements in the manufacture of other optical glass products as well. For example, advances in forming, annealing, and conditioning steps of the laser glass continuous melting process are now being used in manufacture of other large-size optical glasses.

  18. Glass Furnace Combustion and Melting Research Facility.

    SciTech Connect (OSTI)

    Connors, John J.; McConnell, John F.; Henry, Vincent I.; MacDonald, Blake A.; Gallagher, Robert J.; Field, William B.; Walsh, Peter M.; Simmons, Michael C.; Adams, Michael E.; Leadbetter, James M.; Tomasewski, Jack W.; Operacz, Walter J.; Houf, William G.; Davis, James W.; Marvin, Bart G.; Gunner, Bruce E.; Farrell, Rick G.; Bivins, David P.; Curtis, Warren; Harris, James E.

    2004-08-01

    The need for a Combustion and Melting Research Facility focused on the solution of glass manufacturing problems common to all segments of the glass industry was given high priority in the earliest version of the Glass Industry Technology Roadmap (Eisenhauer et al., 1997). Visteon Glass Systems and, later, PPG Industries proposed to meet this requirement, in partnership with the DOE/OIT Glass Program and Sandia National Laboratories, by designing and building a research furnace equipped with state-of-the-art diagnostics in the DOE Combustion Research Facility located at the Sandia site in Livermore, CA. Input on the configuration and objectives of the facility was sought from the entire industry by a variety of routes: (1) through a survey distributed to industry leaders by GMIC, (2) by conducting an open workshop following the OIT Glass Industry Project Review in September 1999, (3) from discussions with numerous glass engineers, scientists, and executives, and (4) during visits to glass manufacturing plants and research centers. The recommendations from industry were that the melting tank be made large enough to reproduce the essential processes and features of industrial furnaces yet flexible enough to be operated in as many as possible of the configurations found in industry as well as in ways never before attempted in practice. Realization of these objectives, while still providing access to the glass bath and combustion space for optical diagnostics and measurements using conventional probes, was the principal challenge in the development of the tank furnace design. The present report describes a facility having the requirements identified as important by members of the glass industry and equipped to do the work that the industry recommended should be the focus of research. The intent is that the laboratory would be available to U.S. glass manufacturers for collaboration with Sandia scientists and engineers on both precompetitive basic research and the solution of proprietary glass production problems. As a consequence of the substantial increase in scale and scope of the initial furnace concept in response to industry recommendations, constraints on funding of industrial programs by DOE, and reorientation of the Department's priorities, the OIT Glass Program is unable to provide the support for construction of such a facility. However, it is the present investigators' hope that a group of industry partners will emerge to carry the project forward, taking advantage of the detailed furnace design presented in this report. The engineering, including complete construction drawings, bill of materials, and equipment specifications, is complete. The project is ready to begin construction as soon as the quotations are updated. The design of the research melter closely follows the most advanced industrial practice, firing by natural gas with oxygen. The melting area is 13 ft x 6 ft, with a glass depth of 3 ft and an average height in the combustion space of 3 ft. The maximum pull rate is 25 tons/day, ranging from 100% batch to 100% cullet, continuously fed, with variable batch composition, particle size distribution, and raft configuration. The tank is equipped with bubblers to control glass circulation. The furnace can be fired in three modes: (1) using a single large burner mounted on the front wall, (2) by six burners in a staggered/opposed arrangement, three in each breast wall, and (3) by down-fired burners mounted in the crown in any combination with the front wall or breast-wall-mounted burners. Horizontal slots are provided between the tank blocks and tuck stones and between the breast wall and skewback blocks, running the entire length of the furnace on both sides, to permit access to the combustion space and the surface of the glass for optical measurements and sampling probes. Vertical slots in the breast walls provide additional access for measurements and sampling. The furnace and tank are to be fully instrumented with standard measuring equipment, such as flow meters, thermocouples, continuous gas composition

  19. THE CHOICE OF THE PROPER REFRACTORY FOR THE CASTING OF HIGH MELTING ELECTROPOSITIVE METALS

    E-Print Network [OSTI]

    Brewer, Leo

    2008-01-01

    for the Casting of High Melting Electropositive Metals Leothe Casting of High Melting Electropositive Metals" (Report

  20. Magnetization plateaus of dipolar spin ice on kagome lattice

    SciTech Connect (OSTI)

    Xie, Y. L.; Wang, Y. L.; Yan, Z. B.; Liu, J.-M.

    2014-05-07

    Unlike spin ice on pyrochlore lattice, the spin ice structure on kagome lattice retains net magnetic charge, indicating non-negligible dipolar interaction in modulating the spin ice states. While it is predicted that the dipolar spin ice on kagome lattice exhibits a ground state with magnetic charge order and ?3?×??3 spin order, our work focuses on the magnetization plateau of this system. By employing the Wang-Landau algorithm, it is revealed that the lattice exhibits the fantastic three-step magnetization in response to magnetic field h along the [10] and [01] directions, respectively. For the h//[1 0] case, an additional ?3/6M{sub s} step, where M{sub s} is the saturated magnetization, is observed in a specific temperature range, corresponding to a new state with charge order and short-range spin order.

  1. IceCube: An Instrument for Neutrino Astronomy

    SciTech Connect (OSTI)

    IceCube Collaboration; Halzen, F.; Klein, S.

    2010-06-04

    Neutrino astronomy beyond the Sun was first imagined in the late 1950s; by the 1970s, it was realized that kilometer-scale neutrino detectors were required. The first such instrument, IceCube, is near completion and taking data. The IceCube project transforms a cubic kilometer of deep and ultra-transparent Antarctic ice into a particle detector. A total of 5,160 optical sensors are embedded into a gigaton of Antarctic ice to detect the Cherenkov light emitted by secondary particles produced when neutrinos interact with nuclei in the ice. Each optical sensor is a complete data acquisition system, including a phototube, digitization electronics, control and trigger systems and LEDs for calibration. The light patterns reveal the type (flavor) of neutrino interaction and the energy and direction of the neutrino, making neutrino astronomy possible. The scientific missions of IceCube include such varied tasks as the search for sources of cosmic rays, the observation of Galactic supernova explosions, the search for dark matter, and the study of the neutrinos themselves. These reach energies well beyond those produced with accelerator beams.

  2. Energy Saving Melting and Revert Reduction Technology: Melting Efficiency in Die Casting Operations

    SciTech Connect (OSTI)

    David Schwam

    2012-12-15

    This project addressed multiple aspects of the aluminum melting and handling in die casting operations, with the objective of increasing the energy efficiency while improving the quality of the molten metal. The efficiency of melting has always played an important role in the profitability of aluminum die casting operations. Consequently, die casters need to make careful choices in selecting and operating melting equipment and procedures. The capital cost of new melting equipment with higher efficiency can sometimes be recovered relatively fast when it replaces old melting equipment with lower efficiency. Upgrades designed to improve energy efficiency of existing equipment may be well justified. Energy efficiency is however not the only factor in optimizing melting operations. Melt losses and metal quality are also very important. Selection of melting equipment has to take into consideration the specific conditions at the die casting shop such as availability of floor space, average quantity of metal used as well as the ability to supply more metal during peaks in demand. In all these cases, it is essential to make informed decisions based on the best available data.

  3. Winter Driving Tips Driving in Ice & Snow

    E-Print Network [OSTI]

    Capogna, Luca

    Winter Driving Tips Driving in Ice & Snow: When you must drive, clear the ice and snow from your in ice and snow, other drivers will be traveling cautiously. Don't disrupt the flow of traffic by driving handle better in ice and snow, but they do not have flawless traction, and skids can occur unexpectedly

  4. Towards a Fine-Resolution Global Coupled Climate System for Prediction...

    Office of Scientific and Technical Information (OSTI)

    58 GEOSCIENCES climate, numerical modeling, earth system model, ocean, sea-ice, mesoscale eddies climate, numerical modeling, earth system model, ocean, sea-ice, mesoscale...

  5. Sputtering of Oxygen Ice by Low Energy Ions

    E-Print Network [OSTI]

    Muntean, E A; Field, T A; Fitzsimmons, A; Hunniford, C A; McCullough, R W

    2015-01-01

    Naturally occurring ices lie on both interstellar dust grains and on celestial objects, such as those in the outer solar system. These ices are continu- ously subjected to irradiation by ions from the solar wind and/or cosmic rays, which modify their surfaces. As a result, new molecular species may form which can be sputtered off into space or planetary atmospheres. We determined the experimental values of sputtering yields for irradiation of oxygen ice at 10 K by singly (He+, C+, N+, O+ and Ar+) and doubly (C2+, N2+ and O2+) charged ions with 4 keV kinetic energy. In these laboratory experiments, oxygen ice was deposited and irradiated by ions in an ultra high vacuum chamber at low temperature to simulate the environment of space. The number of molecules removed by sputtering was observed by measurement of the ice thickness using laser interferometry. Preliminary mass spectra were taken of sputtered species and of molecules formed in the ice by temperature programmed desorption (TPD). We find that the experi...

  6. Vacuum Arc Melting Unit Arc Melting is used for melting metals typically to form alloys. Heating is via an electric arc struck

    E-Print Network [OSTI]

    Subramaniam, Anandh

    Vacuum Arc Melting Unit Arc Melting is used for melting metals­ typically to form alloys. Heating unit is used as a power source. Heat generated by the electric arc struck between the electrode unit. The vacuum unit with rotary and diffusion pumps can attain a vacuum of 106 m bar. The cold

  7. Critical Mechanisms for the Formation of Extreme Arctic Sea-Ice Extent in the Summers of 2007 and 1996

    SciTech Connect (OSTI)

    Dong, Xiquan; Zib, Benjamin J.; Xi, Baike; Stanfield, Ryan; Deng, Yi; Zhang, Xiangdong; Lin, B.; Long, Charles N.

    2014-07-29

    A warming Arctic climate is undergoing significant e 21 nvironmental change, most evidenced by the reduction of Arctic sea-ice extent during the summer. In this study, we examine two extreme anomalies of September sea-ice extent in 2007 and 1996, and investigate the impacts of cloud fraction (CF), atmospheric precipitable water vapor (PWV), downwelling longwave flux (DLF), surface air temperature (SAT), pressure and winds on the sea-ice variation in 2007 and 1996 using both satellite-derived sea-ice products and MERRA reanalysis. The area of the Laptev, East Siberian and West Chukchi seas (70-90oN, 90-180oE) has experienced the largest variation in sea-ice extent from year-to-year and defined here as the Area Of Focus (AOF). The record low September sea-ice extent in 2007 was associated with positive anomalies 30 of CF, PWV, DLF, and SAT over the AOF. Persistent anti-cyclone positioned over the Beaufort Sea coupled with low pressure over Eurasia induced easterly zonal and southerly meridional winds. In contrast, negative CF, PWV, DLF and SAT anomalies, as well as opposite wind patterns to those in 2007, characterized the 1996 high September sea-ice extent. Through this study, we hypothesize the following positive feedbacks of clouds, water vapor, radiation and atmospheric variables on the sea-ice retreat during the summer 2007. The record low sea-ice extent during the summer 2007 is initially triggered by the atmospheric circulation anomaly. The southerly winds across the Chukchi and East Siberian seas transport warm, moist air from the north Pacific, which is not only enhancing sea-ice melt across the AOF, but also increasing clouds. The positive cloud feedback results in higher SAT and more sea-ice melt. Therefore, 40 more water vapor could be evaporated from open seas and higher SAT to form more clouds, which will enhance positive cloud feedback. This enhanced positive cloud feedback will then further increase SAT and accelerate the sea-ice retreat during the summer 2007.

  8. Melting Ice and Tangled Nets: Litigation and Conservation Policy in the US, Australia, and Canada

    E-Print Network [OSTI]

    Shaffer, Robert

    2012-01-01

    Beachfront development, light pollution, and sand compactiondevelopment and light pollution, both of which have been

  9. New climate model predicts likelihood of Greenland ice melt, sea level rise

    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 Home Room NewsInformationJessework usesofPublications64 2.251 2.211New SpeciesNewNationalNew Algaland

  10. Method of forming calthrate ice

    DOE Patents [OSTI]

    Hino, T.; Gorski, A.J.

    1985-09-30

    A method of forming clathrate ice in a supercooled water-based liquid contained in a vessel is disclosed. Initially, an oscillator device is located in the liquid in the vessel. The oscillator device is then oscillated ultransonically so that small crystals are formed in the liquid. Thes small crystals serve as seed crystals for ice formation in the liquid and thereby prevent supercooling of the liquid. Preferably, the oscillating device is controlled by a thermostat which initiates operation of the oscillator device when the temperature of the liquid is lowered to the freezing point. Thereafter, the operation of the oscillator device is terminated when ice is sensed in the liquid by an ice sensor.

  11. Method of forming clathrate ice

    DOE Patents [OSTI]

    Hino, Toshiyuki (Tokyo, JP); Gorski, Anthony J. (Lemont, IL)

    1987-01-01

    A method of forming clathrate ice in a supercooled water-based liquid contained in a vessel is disclosed. Initially, an oscillator device is located in the liquid in the vessel. The oscillator device is then oscillated ultrasonically so that small crystals are formed in the liquid. These small crystals serve as seed crystals for ice formation in the liquid and thereby prevent supercooling of the liquid. Preferably, the oscillating device is controlled by a thermostat which initiates operation of the oscillator device when the temperature of the liquid is lowered to the freezing point. Thereafter, the operation of the oscillator device is terminated when ice is sensed in the liquid by an ice sensor.

  12. Method and apparatus for melting metals

    DOE Patents [OSTI]

    Moore, Alan F.; Schechter, Donald E.; Morrow, Marvin Stanley

    2006-03-14

    A method and apparatus for melting metals uses microwave energy as the primary source of heat. The metal or mixture of metals are placed in a ceramic crucible which couples, at least partially, with the microwaves to be used. The crucible is encased in a ceramic casket for insulation and placed within a microwave chamber. The chamber may be evacuated and refilled to exclude oxygen. After melting, the crucible may be removed for pouring or poured within the chamber by dripping or running into a heated mold within the chamber. Apparent coupling of the microwaves with softened or molten metal produces high temperatures with great energy savings.

  13. Pressurized melt ejection into scaled reactor cavities

    SciTech Connect (OSTI)

    Tarbell, W.W.; Pilch, M.; Brockmann, J.E.; Ross, J.W.; Gilbert, D.W.

    1986-10-01

    This report describes four tests performed in the High-Pressure Melt Streaming Program (HIPS) using linear-scaled cavities of the Zion Nuclear Power Plant. These experiments were conducted to study the phenomena involved in high-pressure ejection of core debris into the cavity beneath the reactor pressure vessel. One-tenth and one-twentieth linear scale models of reactor cavities were constructed and instrumented. The first test used an apparatus constructed of alumina firebrick to minimize the potential interaction between the ejected melt and cavity material. The remaining three experiments used scaled representations of the Zion nuclear plant geometry, constructed of prototypic concrete composition.

  14. Rock melting tool with annealer section

    DOE Patents [OSTI]

    Bussod, Gilles Y. (Santa Fe, NM); Dick, Aaron J. (Oakland, CA); Cort, George E. (Montrose, CO)

    1998-01-01

    A rock melting penetrator is provided with an afterbody that rapidly cools a molten geological structure formed around the melting tip of the penetrator to the glass transition temperature for the surrounding molten glass-like material. An annealing afterbody then cools the glass slowly from the glass transition temperature through the annealing temperature range to form a solid self-supporting glass casing. This allows thermally induced strains to relax by viscous deformations as the molten glass cools and prevents fracturing of the resulting glass liner. The quality of the glass lining is improved, along with its ability to provide a rigid impermeable casing in unstable rock formations.

  15. An experimental and theoretical study of the ice accretion process during artificial and natural icing conditions

    E-Print Network [OSTI]

    Kirby, Mark Samuel

    1986-01-01

    Real-time measurements of ice growth during artificial and natural icing conditions were conducted using an ultrasonic pulse-echo technique. This technique allows ice thickness to be measured with an accuracy of ?0.5 mm; ...

  16. Melt spreading code assessment, modifications, and application to the EPR core catcher design.

    SciTech Connect (OSTI)

    Farmer, M. T .; Nuclear Engineering Division

    2009-03-30

    The Evolutionary Power Reactor (EPR) is under consideration by various utilities in the United States to provide base load electrical production, and as a result the design is undergoing a certification review by the U.S. Nuclear Regulatory Commission (NRC). The severe accident design philosophy for this reactor is based upon the fact that the projected power rating results in a narrow margin for in-vessel melt retention by external cooling of the reactor vessel. As a result, the design addresses ex-vessel core melt stabilization using a mitigation strategy that includes: (1) an external core melt retention system to temporarily hold core melt released from the vessel; (2) a layer of 'sacrificial' material that is admixed with the melt while in the core melt retention system; (3) a melt plug in the lower part of the retention system that, when failed, provides a pathway for the mixture to spread to a large core spreading chamber; and finally, (4) cooling and stabilization of the spread melt by controlled top and bottom flooding. The overall concept is illustrated in Figure 1.1. The melt spreading process relies heavily on inertial flow of a low-viscosity admixed melt to a segmented spreading chamber, and assumes that the melt mass will be distributed to a uniform height in the chamber. The spreading phenomenon thus needs to be modeled properly in order to adequately assess the EPR design. The MELTSPREAD code, developed at Argonne National Laboratory, can model segmented, and both uniform and nonuniform spreading. The NRC is thus utilizing MELTSPREAD to evaluate melt spreading in the EPR design. MELTSPREAD was originally developed to support resolution of the Mark I containment shell vulnerability issue. Following closure of this issue, development of MELTSPREAD ceased in the early 1990's, at which time the melt spreading database upon which the code had been validated was rather limited. In particular, the database that was utilized for initial validation consisted of: (1) comparison to an analytical solution for the dam break problem, (2) water spreading tests in a 1/10 linear scale model of the Mark I containment by Theofanous et al., and (3) steel spreading tests by Suzuki et al. that were also conducted in a geometry similar to the Mark I. The objective of this work was to utilize the MELTSPREAD code to check the assumption of uniform melt spreading in the EPR core catcher design. As a starting point for the project, the code was validated against the worldwide melt spreading database that emerged after the code was originally written in the very early 1990's. As part of this exercise, the code was extensively modified and upgraded to incorporate findings from these various analytical and experiment programs. In terms of expanding the ability of the code to analyze various melt simulant experiments, the options to input user-specified melt and/or substrate material properties was added. The ability to perform invisicid and/or adiabatic spreading analysis was also added so that comparisons with analytical solutions and isothermal spreading tests could be carried out. In terms of refining the capability to carry out reactor material melt spreading analyses, the code was upgraded with a new melt viscosity model; the capability was added to treat situations in which solid fraction buildup between the liquidus-solidus is non-linear; and finally, the ability to treat an interfacial heat transfer resistance between the melt and substrate was incorporated. This last set of changes substantially improved the predictive capability of the code in terms of addressing reactor material melt spreading tests. Aside from improvements and upgrades, a method was developed to fit the model to the various melt spreading tests in a manner that allowed uncertainties in the model predictions to be statistically characterized. With these results, a sensitivity study was performed to investigate the assumption of uniform spreading in the EPR core catcher that addressed parametric variations in: (1) melt pour mass, (2) melt composition, (3) me

  17. Storage of Dressed Chinook Salmon, Oncorhynchus tshawytscha, in Refrigerated Freshwater, Diluted Seawater, Seawater, and in Ice

    E-Print Network [OSTI]

    Storage of Dressed Chinook Salmon, Oncorhynchus tshawytscha, in Refrigerated Freshwater, Diluted during storage. Iced storage offers several advantages over the water chilling systems, including little by 25 per- cent within four days after transfer to ice, and weight gained during water storage was lost

  18. Tidally driven ice speed variation at Helheim Glacier, Greenland, observed with terrestrial radar interferometry

    E-Print Network [OSTI]

    Holland, David

    Tidally driven ice speed variation at Helheim Glacier, Greenland, observed with terrestrial radar Space Flight Center, Greenbelt, MD, USA 4 Earth System Science Interdisciplinary Center, University is usually packed with dense ice melange. Helheim Glacier accelerated and retreated between 2000 and 2005

  19. Evaluation of Arctic sea ice thickness simulated by Arctic Ocean Model Intercomparison Project models

    E-Print Network [OSTI]

    Zhang, Jinlun

    Evaluation of Arctic sea ice thickness simulated by Arctic Ocean Model Intercomparison Project March 2012. [1] Six Arctic Ocean Model Intercomparison Project model simulations are compared and Assimilation System models. Citation: Johnson, M., et al. (2012), Evaluation of Arctic sea ice thickness

  20. Office Building Uses Ice Storage, Heat Recovery, and Cold-Air Distribution 

    E-Print Network [OSTI]

    Tackett, R. K.

    1989-01-01

    Ice storage offers many opportunities to use other tcchnologies, such as heat recovery and cold-air distribution. In fact, by using them, the designer can improve the efficiency and lower the construction cost of an ice system. This paper presents a...

  1. Method for the melting of metals

    DOE Patents [OSTI]

    White, Jack C. (Albany, OR); Traut, Davis E. (Corvallis, OR)

    1992-01-01

    A method of quantitatively determining the molten pool configuration in melting of metals. The method includes the steps of introducing hafnium metal seeds into a molten metal pool at intervals to form ingots, neutron activating the ingots and determining the hafnium location by radiometric means. Hafnium possesses exactly the proper metallurgical and radiochemical properties for this use.

  2. Energy Savings in Electric Arc Furnace Melting 

    E-Print Network [OSTI]

    Lubbeck, W.

    1982-01-01

    Arc furnace melting which at one time was almost exclusively used to produce alloy steel and steel castings is now widely accepted in the industry as an efficient process to produce all types of steel and iron. Presently, about 28% of steel...

  3. Heterogeneous ice nucleation and water uptake by field-collected atmospheric particles below 273 K

    SciTech Connect (OSTI)

    Wang, Bingbing; Laskin, Alexander; Roedel, Tobias R.; Gilles, Marry K.; Moffet, Ryan C.; Tivanski, Alexei V.; Knopf, Daniel A.

    2012-09-25

    Atmospheric ice formation induced by particles with complex chemical and physical properties through heterogeneous nucleation is not well understood. Heterogeneous ice nucleation and water uptake by ambient particles collected from urban environments in Los Angeles and Mexico City are presented. Using a vapour controlled cooling system equipped with an optical microscopy, the range of onset conditions for ice nucleation and water uptake by the collected particles was determined as a function of temperature (200{273 K) and relative humidity with respect to ice (RHice) up to water saturation. Three distinctly different types of authentic atmospheric particles were investigated including soot particles associated with organics/inorganics, inorganic particles of marine origin coated with organic material, and Pb/Zn containing inorganic particles apportioned to anthropogenic emissions relevant to waste incineration. Single particle characterization was provided by micro-spectroscopic analyses using computer controlled scanning electron microscopy with energy dispersive analysis of X-rays (CCSEM/EDX) and scanning transmission X-ray microscopy with near edge X-ray absorption ne structure spectroscopy (STXM/NEXAFS). Above 230 K, signicant differences in water uptake and immersion freezing effciencies of the different particle types were observed. Below 230 K, the particles exhibited high deposition ice nucleation effciencies and formed ice at RHice values well below homogeneous ice nucleation limits. The data show that the chemical composition of these eld{collected particles plays an important role in determining water uptake and immersion freezing. Heterogeneous ice nucleation rate coeffcients, cumulative ice nuclei (IN) spectrum, and IN activated fraction for deposition ice nucleation are derived. The presented ice nucleation data demonstrate that anthropogenic and marine particles comprising of various chemical and physical properties exhibit distinctly different ice nucleation effciencies and can serve as effcient IN at atmospheric conditions typical for cirrus and mixed phase clouds. This indicates a potential link between human activities and cloud formation, and thus climate.

  4. High pressure ejection of melt from a reactor pressure vessel. The discharge phase. Revision 7

    SciTech Connect (OSTI)

    Pilch, M.; Tarbell, W.M.

    1985-09-01

    Recent probabilistic risk-assessment studies identified potential accident sequences in which reactor vessel failure occurs while the primary system is at elevated pressure. The phenomenology of the discharge phase is reviewed here. We propose an improved model for hole ablation following vessel failure, and we compare the model with experiment data. Gas blowthrough is identified as a mechanism that allows steam to escape through the vessel breach before melt ejection is complete. Gas blowthrough leads to pneumatic atomization of the remaining melt before significant depressurization of the primary system occurs.

  5. Ice at the Interface: Atmosphere-Ice-Ocean Boundary Layer Processes and Their Role in Polar Change---Workshop Report

    SciTech Connect (OSTI)

    Hunke, Elizabeth C. [Los Alamos National Laboratory

    2012-07-23

    The atmosphere-ocean boundary layer in which sea ice resides includes many complex processes that require a more realistic treatment in GCMs, particularly as models move toward full earth system descriptions. The primary purpose of the workshop was to define and discuss such coupled processes from observational and modeling points of view, including insight from both the Arctic and Antarctic systems. The workshop met each of its overarching goals, including fostering collaboration among experimentalists, theorists and modelers, proposing modeling strategies, and ascertaining data availability and needs. Several scientific themes emerged from the workshop, such as the importance of episodic or extreme events, precipitation, stratification above and below the ice, and the marginal ice zone, whose seasonal Arctic migrations now traverse more territory than in the past.

  6. Dynamics and pattern selection at the crystal-melt interface

    SciTech Connect (OSTI)

    Cummins, H.Z.

    1990-01-01

    This report discusses: light scattering at the crystal-melt interface; morphological instability and pattern selection; and sidebranching.

  7. Coherent radar ice thickness measurements over the Greenland ice sheet

    E-Print Network [OSTI]

    Gogineni, S. Prasad; Tammana, Dilip; Braaten, David A.; Leuschen, C.; Legarsky, J.; Kanagaratnam, P.; Stiles, J.; Allen, C.; Jezek, K.; Akins, T. L.

    2001-12-27

    averaged over a distance covered by aircraft in 1 s (-130 m).) tt(X, g = -d) = Sice(t: T, x). (6) The value t = - can be interpreted as the time when S ice(t, x) represents the wave energy due to scattering specifically from depth d, as opposed... of the Greenland ice sheet produced by Mark Fahnestock (Department of Meteorology, University of Maryland, College Park) and Ron Kwok (Jet Propulsion Laboratory, California Institute of Technology, Pasa- dena). The helpful suggestions and comments of two...

  8. Runoff simulations from the Greenland ice sheet at Kangerlussuaq from 2006-2007 to 2007/08. West Greenland

    SciTech Connect (OSTI)

    Mernild, Sebastian Haugard [Los Alamos National Laboratory; Hasholt, Bent [UNIV OF COPENHAGEN; Van Den Broeke, Michiel [UTRECHT UNIV; Liston, Glen [COLORADO STATE UNIV

    2009-01-01

    This study focuses on runoff from a large sector of the Greenland Ice Sheet (GrIS) - the Kangerlussuaq drainage area, West Greenland - for the runoff observation period 2006/07 to 2007/08. SnowModel, a state-of-the-art snow-evolution modeling system, was used to simulate winter accumulation and summer ablation processes, including runoff. Independent in situ end-of-winter snow depth and high-resolution runoff observations were used for validation of simulated accumulation and ablation processes. Runoff was modeled on both daily and hourly time steps, filling a data gap of runoff exiting part of the GrIS. Using hourly meteorological driving data instead of smoothed daily-averaged data produced more realistic meteorological conditions in relation to snow and melt threshold surface processes, and produced 6-17% higher annual cumulative runoff. The simulated runoff series yielded useful insights into the present conditions of inter-seasonal and inter-annual variability of Kangerlussuaq runoff, and provided an acceptable degree of agreement between simulated and observed runoff. The simulated spatial runoff distributions, in some areas of the GrIS terminus, were as high as 2,750 mm w.eq. of runoff for 2006/07, while only 900 mm w.eq was simulated for 2007/08. The simulated total runoff from Kangerlussuaq was 1.9 km{sup 3} for 2006/07 and 1.2 km{sup 3} for 2007/08, indicating a reduction of 35-40% caused by the climate conditions and changes in the GrIS freshwater storage. The reduction in runoff from 2006/07 to 2007/08 occurred simultaneously with the reduction in the overall pattern of satellite-derived GrIS surface melt from 2007 to 2008.

  9. Low melting high lithia glass compositions and methods

    DOE Patents [OSTI]

    Jantzen, Carol M. (Aiken, SC); Pickett, John B. (Aiken, SC); Cicero-Herman, Connie A. (Aiken, SC); Marra, James C. (Aiken, SC)

    2000-01-01

    The invention relates to methods of vitrifying waste and for lowering the melting point of glass forming systems by including lithia formers in the glass forming composition in significant amounts, typically from about 0.16 wt % to about 11 wt %, based on the total glass forming oxides. The lithia is typically included as a replacement for alkali oxide glass formers that would normally be present in a particular glass forming system. Replacement can occur on a mole percent or weight percent basis, and typically results in a composition wherein lithia forms about 10 wt % to about 100 wt % of the alkali oxide glass formers present in the composition. The present invention also relates to the high lithia glass compositions formed by these methods. The invention is useful for stabilization of numerous types of waste materials, including aqueous waste streams, sludge solids, mixtures of aqueous supernate and sludge solids, combinations of spent filter aids from waste water treatment and waste sludges, supernate alone, incinerator ash, incinerator offgas blowdown, or combinations thereof, geological mine tailings and sludges, asbestos, inorganic filter media, cement waste forms in need of remediation, spent or partially spent ion exchange resins or zeolites, contaminated soils, lead paint, etc. The decrease in melting point achieved by the present invention desirably prevents volatilization of hazardous or radioactive species during vitrification.

  10. Low melting high lithia glass compositions and methods

    DOE Patents [OSTI]

    Jantzen, Carol M.; Pickett, John B.; Cicero-Herman, Connie A.; Marra, James C.

    2004-11-02

    The invention relates to methods of vitrifying waste and for lowering the melting point of glass forming systems by including lithia formers in the glass forming composition in significant amounts, typically from about 0.16 wt % to about 11 wt %, based on the total glass forming oxides. The lithia is typically included as a replacement for alkali oxide glass formers that would normally be present in a particular glass forming system. Replacement can occur on a mole percent or weight percent basis, and typically results in a composition wherein lithia forms about 10 wt % to about 100 wt % of the alkali oxide glass formers present in the composition. The present invention also relates to the high lithia glass compositions formed by these methods. The invention is useful for stabilization of numerous types of waste materials, including aqueous waste streams, sludge solids, mixtures of aqueous supernate and sludge solids, combinations of spent filter aids from waste water treatment and waste sludges, supernate alone, incinerator ash, incinerator offgas blowdown, or combinations thereof, geological mine tailings and sludges, asbestos, inorganic filter media, cement waste forms in need of remediation, spent or partially spent ion exchange resins or zeolites, contaminated soils, lead paint, etc. The decrease in melting point achieved by the present invention desirably prevents volatilization of hazardous or radioactive species during vitrification.

  11. Low melting high lithia glass compositions and methods

    DOE Patents [OSTI]

    Jantzen, Carol M.; Pickett, John B.; Cicero-Herman, Connie A.; Marra, James C.

    2003-10-07

    The invention relates to methods of vitrifying waste and for lowering the melting point of glass forming systems by including lithia formers in the glass forming composition in significant amounts, typically from about 0.16 wt % to about 11 wt %, based on the total glass forming oxides. The lithia is typically included as a replacement for alkali oxide glass formers that would normally be present in a particular glass forming system. Replacement can occur on a mole percent or weight percent basis, and typically results in a composition wherein lithia forms about 10 wt % to about 100 wt % of the alkali oxide glass formers present in the composition. The present invention also relates to the high lithia glass compositions formed by these methods. The invention is useful for stabilization of numerous types of waste materials, including aqueous waste streams, sludge solids, mixtures of aqueous supernate and sludge solids, combinations of spent filter aids from waste water treatment and waste sludges, supernate alone, incinerator ash, incinerator offgas blowdown, or combinations thereof, geological mine tailings and sludges, asbestos, inorganic filter media, cement waste forms in need of remediation, spent or partially spent ion exchange resins or zeolites, contaminated soils, lead paint, etc. The decrease in melting point achieved by the present invention desirably prevents volatilization of hazardous or radioactive species during vitrification.

  12. 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 ...

  13. The convective desalination of sea ice

    E-Print Network [OSTI]

    Rees Jones, David

    2014-07-01

    in the interstices of an ice matrix. My focus is on one of the processes by which the salt content of sea ice decreases, namely convective desalination, which is also often called gravity drainage by geophysicists. Modelling convective desalination requires...

  14. Evaluation of Cloud-resolving and Limited Area Model Intercomparison Simulations using TWP-ICE Observations. Part 2: Rain Microphysics

    SciTech Connect (OSTI)

    Varble, Adam; Zipser, Edward J.; Fridlind, Ann; Zhu, Ping; Ackerman, Andrew; Chaboureau, Jean-Pierre; Fan, Jiwen; Hill, Adrian; Shipway, Ben; Williams, Christopher R.

    2014-12-27

    Ten 3D cloud-resolving model (CRM) simulations and four 3D limited area model (LAM) simulations of an intense mesoscale convective system observed on January 23-24, 2006 during the Tropical Warm Pool – International Cloud Experiment (TWP-ICE) are compared with each other and with observations and retrievals from a scanning polarimetric radar, co-located UHF and VHF vertical profilers, and a Joss-Waldvogel disdrometer in an attempt to explain published results showing a low bias in simulated stratiform rainfall. Despite different forcing methodologies, similar precipitation microphysics errors appear in CRMs and LAMs with differences that depend on the details of the bulk microphysics scheme used. One-moment schemes produce too many small raindrops, which biases Doppler velocities low, but produces rain water contents (RWCs) that are similar to observed. Two-moment rain schemes with a gamma shape parameter (?) of 0 produce excessive size sorting, which leads to larger Doppler velocities than those produced in one-moment schemes, but lower RWCs than observed. Two moment schemes also produce a convective median volume diameter distribution that is too broad relative to observations and thus, may have issues balancing raindrop formation, collision coalescence, and raindrop breakup. Assuming a ? of 2.5 rather than 0 for the raindrop size distribution improves one-moment scheme biases, and allowing ? to have values greater than 0 may improve two-moment schemes. Under-predicted stratiform rain rates are associated with under-predicted ice water contents at the melting level rather than excessive rain evaporation, in turn likely associated with convective detrainment that is too high in the troposphere and mesoscale circulations that are too weak. In addition to stronger convective updrafts than observed, limited domain size prevents a large, well-developed stratiform region from developing in CRMs, while a dry bias in ECMWF analyses does the same to the LAMs.

  15. Stable levitation and dynamics of ice particles at low pressures

    E-Print Network [OSTI]

    Nicholas Kowalski; Bernard Xie; Colin V. Parker; Cheng Chin

    2015-04-13

    We demonstrate stable levitation and trapping of ice particles of 30~200 micon at low background gas pressures in the presence of a temperature gradient. The thermophoretic force levitates the particles, which have long lifetimes of over an hour. The equilibrium position depends on the background pressure and temperature gradient, which is consistent with theoretical expectations. Furthermore, we investigate interesting launching and merging dynamics of the levitated particles, as well as the development of instability at high background pressures. Our system provides a robust platform to investigate the aggregation of floating ice particles in air, and potentially chemical and biological processes in a microgravity environment.

  16. Electrical properties of saline ices and ice-silicate mixtures: geophysical and astrobiological consequences (Invited)

    E-Print Network [OSTI]

    Stillman, David E.

    MR22A-05 Electrical properties of saline ices and ice-silicate mixtures: geophysical) electrical-properties measurements of laboratory- produced saline ice, salt hydrates, and ice of interior properties, and habitability. The electrical properties of saline H2O are controlled by the binary

  17. PROJECT SUMMARY: Ocean Surfaces on Snowball Earth Submitted to NSF Polar Programs (Antarctic Integrated and System Science), June 2007

    E-Print Network [OSTI]

    Winglee, Robert M.

    not experienced melting. Laboratory work will investigate the migration of salt in sea ice, the optical properties evolution through this climatic bottleneck, and for interpretation of Neoproterozoic glacial deposits

  18. Performance of a stand-alone wind-electric ice maker for remote villages

    SciTech Connect (OSTI)

    Davis, H.C. [National Renewable Energy Lab., Golden, CO (United States); Brandemuehl, M.J. [University of Colorado, Boulder, CO (United States). Joint Center for Energy Management; Bergey, M.L.S. [Bergey Windpower Co., Norman, OK (United States)

    1995-01-01

    Two ice makers in the 1.1 metric tons per 24 hours (1.2 tons per day) size range were tested to determine their performance when directly coupled to a variable-frequency wind turbine generator. Initial tests were conducted using a dynamometer to simulate to wind to evaluate whether previously determined potential problems were significant and to define basic performance parameters. Field testing in Norman, Oklahoma, was completed to determine the performance of one of the ice makers under real wind conditions. As expected, the ice makers produced more ice at a higher speed than rated, and less ice at a lower speed. Due to the large start-up torque requirement of reciprocating compressors, the ice making system experienced a large start-up current and corresponding voltage drop which required a larger wind turbine that expected to provide the necessary current and voltage. Performance curves for ice production and power consumption are presented. A spreadsheet model was constructed to predict ice production at a user-defined site given the wind conditions for that location. Future work should include long-term performance tests and research on reducing the large start-up currents the system experiences when first coming on line.

  19. http://www.ices.cmu.edu/ballista Prof. Philip Koopman

    E-Print Network [OSTI]

    Koopman, Philip

    http://www.ices.cmu.edu/ballista Prof. Philip Koopman koopman@cmu.edu - (412) 268-5225 - http robustness #12;3 Overview: Automated Robustness Testing u System Robustness · Motivation · Ballista automatic · Technology Transfer · Application to Non OS APIs u Conclusions A Ballista is an ancient siege weapon

  20. Physics of polymer melts: A novel perspective

    E-Print Network [OSTI]

    Shirish M. Chitanvis

    2000-02-25

    We have mapped the physics of polymer melts onto a time-dependent Landau-Ginzburg $|\\psi|^4$ field theory using techniques of functional integration. Time in the theory is simply a label for the location of a given monomer along the extent of a flexible chain. With this model, one can show that the limit of infinitesimal concentration of a polymer melt corresponds to a {\\em dynamic} critical phenomenon. The transition to the entangled state is also shown to be a critical point. For larger concentrations, when the role of fluctuations is reduced, a mean field approximation is justifiably employed to show the existence of tube-like structures reminiscent of Edwards' model.

  1. Thermally efficient melting for glass making

    DOE Patents [OSTI]

    Chen, Michael S. K. (Zionsville, PA); Painter, Corning F. (Allentown, PA); Pastore, Steven P. (Allentown, PA); Roth, Gary (Trexlertown, PA); Winchester, David C. (Allentown, PA)

    1991-01-01

    The present invention is an integrated process for the production of glass utilizing combustion heat to melt glassmaking materials in a glassmaking furnace. The fuel combusted to produce heat sufficient to melt the glassmaking materials is combusted with oxygen-enriched oxidant to reduce heat losses from the offgas of the glassmaking furnace. The process further reduces heat losses by quenching hot offgas from the glassmaking furnace with a process stream to retain the heat recovered from quench in the glassmaking process with subsequent additional heat recovery by heat exchange of the fuel to the glassmaking furnace, as well as the glassmaking materials, such as batch and cullet. The process includes recovery of a commercially pure carbon dioxide product by separatory means from the cooled, residual offgas from the glassmaking furnace.

  2. Low-melting point heat transfer fluid

    DOE Patents [OSTI]

    Cordaro, Joseph Gabriel (Oakland, CA); Bradshaw, Robert W. (Livermore, CA)

    2010-11-09

    A low-melting point, heat transfer fluid made of a mixture of five inorganic salts including about 29.1-33.5 mol % LiNO.sub.3, 0-3.9 mol % NaNO.sub.3, 2.4-8.2 mol % KNO.sub.3, 18.6-19.9 mol % NaNO.sub.2, and 40-45.6 mol % KNO.sub.2. These compositions can have liquidus temperatures below 80.degree. C. for some compositions.

  3. Shallow melt apparatus for semicontinuous czochralski crystal growth

    DOE Patents [OSTI]

    Wang, Tihu; Ciszek, Theodore F.

    2006-01-10

    In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt crucible (20) to eliminate the necessity supplying a large quantity of feed stock materials that had to be preloaded in a deep crucible to grow a large ingot, comprising a gas tight container a crucible with a deepened periphery (25) to prevent snapping of a shallow melt and reduce turbulent melt convection; source supply means for adding source material to the semiconductor melt; a double barrier (23) to minimize heat transfer between the deepened periphery (25) and the shallow melt in the growth compartment; offset holes (24) in the double barrier (23) to increase melt travel length between the deepened periphery (25) and the shallow growth compartment; and the interface heater/heat sink (22) to control the interface shape and crystal growth rate.

  4. Behavior of melts during softening and melting down of iron ore sinter under load

    SciTech Connect (OSTI)

    Cho, Y.H. [Research Inst. of Industrial Science and Technology, Pohang (Korea, Republic of)

    1995-12-01

    In order to achieve effective operation in the blast furnace, the distribution control and quality improvement of burden materials are very important. In spite of the difficulties in obtaining suitable samples and making direct observation, significant progress including the placement of probes into the stack, tuyere drilling and laboratory simulation studies has been made. Investigation of the behavior of melts during softening and melting down was carried out in the temperature range of 800 C to 1,515 C. In this report, emphasis is given to investigating the mineral formation and properties of melts during softening and melting down of the iron ore sinter. Sized coke layers were placed above and below the sample to maintain uniform upward flow of gas and insure a smooth downward flow of melts. When the temperature of the sample reached the set point during the test the power was shut off and the sample was cooled in the furnace air. The weight, the height, porosity and contraction of each sample were measured. Chemical composition, observation of microstructures, SEM analysis and X-ray diffraction analysis were conducted. Results are presented.

  5. Medical ice slurry production device

    DOE Patents [OSTI]

    Kasza, Kenneth E. (Palos Park, IL); Oras, John (Des Plaines, IL); Son, HyunJin (Naperville, IL)

    2008-06-24

    The present invention relates to an apparatus for producing sterile ice slurries for medical cooling applications. The apparatus is capable of producing highly loaded slurries suitable for delivery to targeted internal organs of a patient, such as the brain, heart, lungs, stomach, kidneys, pancreas, and others, through medical size diameter tubing. The ice slurry production apparatus includes a slurry production reservoir adapted to contain a volume of a saline solution. A flexible membrane crystallization surface is provided within the slurry production reservoir. The crystallization surface is chilled to a temperature below a freezing point of the saline solution within the reservoir such that ice particles form on the crystallization surface. A deflector in the form of a reciprocating member is provided for periodically distorting the crystallization surface and dislodging the ice particles which form on the crystallization surface. Using reservoir mixing the slurry is conditioned for easy pumping directly out of the production reservoir via medical tubing or delivery through other means such as squeeze bottles, squeeze bags, hypodermic syringes, manual hand delivery, and the like.

  6. $1/f$ noise on the brink of wet granular melting

    E-Print Network [OSTI]

    Kai Huang

    2015-07-23

    The collective behavior of a two-dimensional wet granular cluster under horizontal swirling motions is investigated experimentally. Depending on the balance between the energy injection and dissipation, the cluster evolves into various nonequilibrium stationary states with strong internal structure fluctuations with time. Quantitative characterizations of the fluctuations with the bond orientational order parameter $q_{\\rm 6}$ reveal power spectra of the form $f^{\\alpha}$ with the exponent $\\alpha$ closely related to the stationary states of the system. In particular, $1/f$ type of noise with $\\alpha\\approx-1$ emerges as melting starts from the free surface of the cluster, suggesting the possibility of using $1/f$ noise as an indicator for phase transitions in systems driven far from thermodynamic equilibrium.

  7. Eutectic precipitation of melt quenched titanium-silicon-neodymium alloy

    SciTech Connect (OSTI)

    Li, G.P.; Liu, Y.Y.; Li, D.; Hu, Z.Q. . Inst. of Metal Research)

    1995-01-15

    Titanium based metallic glasses have attracted keen interest because of the promise of industrial applications owing to their improves corrosion resistance, better mechanical properties, occurrence of superconductivity and superior magnetic properties. The titanium alloy systems where metallic glass has been obtained include Ti-Cu, Ti-Be, Ti-Si, Ti-B. Polk et al. had reported that they were able to produce an amorphous phase in binary Ti[sub 80]Si[sub 20] alloy system by using an arc-melting piston and anvil apparatus. In the present study, the authors have investigated the effect of adding rare earth element Nd on eutective precipitation of the amorphous Ti[sub 80]Si[sub 20] alloy and the orientation relationship which exists between the [beta]-Ti and Ti[sub 5]Si[sub 3].

  8. Theory of melting at high pressures: Amending density functional theory with quantum Monte Carlo

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

    Shulenburger, L.; Desjarlais, M. P.; Mattsson, T. R.

    2014-10-01

    We present an improved first-principles description of melting under pressure based on thermodynamic integration comparing Density Functional Theory (DFT) and quantum Monte Carlo (QMC) treatments of the system. The method is applied to address the longstanding discrepancy between density functional theory (DFT) calculations and diamond anvil cell (DAC) experiments on the melting curve of xenon, a noble gas solid where van der Waals binding is challenging for traditional DFT methods. The calculations show excellent agreement with data below 20 GPa and that the high-pressure melt curve is well described by a Lindemann behavior up to at least 80 GPa, amore »finding in stark contrast to DAC data.« less

  9. Effect of Drug Loading and Laser Surface Melting on Drug Release Profile from Biodegradable Polymer

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    Effect of Drug Loading and Laser Surface Melting on Drug Release Profile from Biodegradable Polymer(L-lactic acid) is promising in drug delivery applications because it allows for drug release in a controlled manner. In a polymer-based drug delivery system, drug release is controlled by polymer degradation

  10. Effect of Drug Loading and Laser Surface Melting on Drug Release Profile from Biodegradable Polymer

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    1 Effect of Drug Loading and Laser Surface Melting on Drug Release Profile from Biodegradable The biodegradable polymer such as poly(L-lactic acid) is promising in drug delivery applications because it allows for drug release in a controlled manner. In a polymer-based drug delivery system, drug release

  11. Tropical North Atlantic Hydrologic Cycle Variability in the Florida Straits During the Last Ice Age 

    E-Print Network [OSTI]

    Them, Theodore

    2012-10-19

    Abrupt, millennial-scale climate oscillations, known as Dansgaard-Oeschger (D-O) cycles, characterized the climate system during the last ice age. Proxy evidence suggests these climate oscillations resulted in global-scale reorganizations...

  12. Odd-even effect of melting finite polymer film on square lattice

    E-Print Network [OSTI]

    Tieyan Si

    2015-03-24

    Two dimensional film system bears many exotic thermodynamics behaviors. We proposed a mathematical physics model to explore how the melting temperature of a two dimensional mathematical dimer film depends on the odd-eveness of the finite width of dimer film. A weak external bond between dimers is introduced into the classical dimer model in this dimer film. We derived a general equation of melting temperature and applied it for computing the melting temperature of a dimer film covering a finite square lattice. The melting temperature is proportional to the external bonding energy that we assume it binds neighboring dimers together and proportional to the inverse of entropy per site. Further more, it shows fusing two small rectangular dimer film with odd number of length into one big rectangular film gains more entropy than fusing two small rectangles with even number of length into the same big rectangle. Fusing two small toruses with even number of length into one big torus reduces entropy. Fusing two small toruses with odd number of length increases the entropy. Thus two dimer films with even number of length repel each other, two dimer films with odd length attract each other. The odd-even effect is also reflected on the correlation function of two topologically distinguishable loops in a torus surface. The entropy of finite system dominates odd-even effect. This model has straightforward extension to longer polymers and three dimensional systems.

  13. Melting Instantons, Domain Walls, and Large N

    E-Print Network [OSTI]

    H. B. Thacker

    2008-10-22

    Monte Carlo studies of $CP^{N-1}$ sigma models have shown that the structure of topological charge in these models undergoes a sharp transition at $N=N_c\\approx 4$. For $NN_c$ it is dominated by extended, thin, 1-dimensionally coherent membranes of topological charge, which can be interpreted as domain walls between discrete quasi-stable vacua. These vacua differ by a unit of background electric flux. The transition can be identified as the delocalization of topological charge, or "instanton melting," a phenomenon first suggested by Witten to resolve the conflict between instantons and large $N$ behavior. Implications for $QCD$ are discussed.

  14. Microwave Melting | Y-12 National Security Complex

    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 WebQuantityBonneville Power Administration wouldMass map shines light on77 PAGE OFDetection ofOctober10 Years2,2004Microwave Melting

  15. Bedmap2: improved ice bed, surface and thickness datasets for Antarctica

    E-Print Network [OSTI]

    2013-01-01

    Surface configuration, ice thick- ness, volume and bedrockconstruction of the ice thick- ness grids. between flightof the physical ice thick- ness, rather than an “ice-

  16. Partial melting and melt segregation in a convecting mantle Harro Schmeling*

    E-Print Network [OSTI]

    Schmeling, Harro

    Abstract Various causes for mantle melting (decompression, heating or release of water) combined that the earth is a giant heat engine powered partly by primordial heat and partly by the decay of long lived in a deforming medium are discussed with emphasis on the physical processes involved. To combine these processes

  17. Shallow Melt Apparatus for Semicontinuous Czochralski Crystal Growth

    DOE Patents [OSTI]

    Wang, T.; Ciszek, T. F.

    2006-01-10

    In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt crucible (20) to eliminate the necessity supplying a large quantity of feed stock materials that had to be preloaded in a deep crucible to grow a large ingot, comprising a gas tight container a crucible with a deepened periphery (25) to prevent snapping of a shallow melt and reduce turbulent melt convection; source supply means for adding source material to the semiconductor melt; a double barrier (23) to minimize heat transfer between the deepened periphery (25) and the shallow melt in the growth compartment; offset holes (24) in the double barrier (23) to increase melt travel length between the deepened periphery (25) and the shallow growth compartment; and the interface heater/heat sink (22) to control the interface shape and crystal growth rate.

  18. Hydrogen ICE Vehicle Testing Activities

    SciTech Connect (OSTI)

    J. Francfort; D. Karner

    2006-04-01

    The Advanced Vehicle Testing Activity teamed with Electric Transportation Applications and Arizona Public Service to develop and monitor the operations of the APS Alternative Fuel (Hydrogen) Pilot Plant. The Pilot Plant provides 100% hydrogen, and hydrogen and compressed natural gas (H/CNG)-blended fuels for the evaluation of hydrogen and H/CNG internal combustion engine (ICE) vehicles in controlled and fleet testing environments. Since June 2002, twenty hydrogen and H/CNG vehicles have accumulated 300,000 test miles and 5,700 fueling events. The AVTA is part of the Department of Energy’s FreedomCAR and Vehicle Technologies Program. These testing activities are managed by the Idaho National Laboratory. This paper discusses the Pilot Plant design and monitoring, and hydrogen ICE vehicle testing methods and results.

  19. On the theory of proton solid echo in polymer melts

    E-Print Network [OSTI]

    Fatkullin, N; Mattea, C; Stapf, S

    2015-01-01

    Based on a modified Anderson-Weiss approximation (N. Fatkullin, A. Gubaidullin, C. Mattea, S.Stapf, J. Chem. Phys. 137 (2012), 224907) an improved theory of proton spin solid echo in polymer melts is formulated, taking into account contribution from intermolecular magnetic dipole-dipole interactions. The solid echo build-up function defined by the relation , where , and are the respective signals arising from ( ),( ) and ( ) spin echo experiments, where is an operator rotating the spin system on the angle relatively axis , is investigated. It is shown that the intermolecular part of this function at short times , where is a characteristic time for flip-flop transitions between proton spins, contains information about the relative mean squared displacements of polymer segments at different macromolecules, opening up a new opportunity for obtaining information about polymer dynamics in the millisecond regime.

  20. Ice-lens formation and geometrical supercooling in soils and other colloidal materials

    E-Print Network [OSTI]

    Robert W. Style; Stephen S. L. Peppin; Alan C. F. Cocks; John S. Wettlaufer

    2011-09-09

    We present a new, physically-intuitive model of ice-lens formation and growth during the freezing of soils and other dense, particulate suspensions. Motivated by experimental evidence, we consider the growth of an ice-filled crack in a freezing soil. At low temperatures, ice in the crack exerts large pressures on the crack walls that will eventually cause the crack to split open. We show that the crack will then propagate across the soil to form a new lens. The process is controlled by two factors: the cohesion of the soil, and the geometrical supercooling of the water in the soil; a new concept introduced to measure the energy available to form a new ice lens. When the supercooling exceeds a critical amount (proportional to the cohesive strength of the soil) a new ice lens forms. This condition for ice-lens formation and growth does not appeal to any ad hoc, empirical assumptions, and explains how periodic ice lenses can form with or without the presence of a frozen fringe. The proposed mechanism is in good agreement with experiments, in particular explaining ice-lens pattern formation, and surges in heave rate associated with the growth of new lenses. Importantly for systems with no frozen fringe, ice-lens formation and frost heave can be predicted given only the unfrozen properties of the soil. We use our theory to estimate ice-lens growth temperatures obtaining quantitative agreement with the limited experimental data that is currently available. Finally we suggest experiments that might be performed in order to verify this theory in more detail. The theory is generalizable to complex natural-soil scenarios, and should therefore be useful in the prediction of macroscopic frost heave rates.

  1. Proceedings of the 1996 spring technical conference of the ASME Internal Combustion Engine Division. Volume 2: Engine design and engine systems; ICE-Volume 26-2

    SciTech Connect (OSTI)

    Uzkan, T.

    1996-12-31

    Although the cost of the petroleum crude has not increased much within the last decade, the drive to develop internal combustion engines is still continuing. The basic motivation of this drive is to reduce both emissions and costs. Recent developments in computer chip production and information management technology have opened up new applications in engine controls and monitoring. The development of new information is continuing at a rapid pace. Some of these research and development results were presented at the 1996 Spring Technical Conference of the ASME Internal Combustion Engine Division in Youngstown, Ohio, April 21--24, 1996. The papers presented covered various aspects of the design, development, and application of compression ignition and spark ignition engines. The conference was held at the Holiday Inn Metroplex Complex and hosted by Altronic Incorporated of Girard, Ohio. The written papers submitted to the conference have been published in three conference volumes. Volume 2 includes the papers on the topics of engine design, engine systems, and engine user experience.

  2. Energy-Efficient Melting and Direct Delivery of High Quality...

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

    High Quality Molten Aluminum itmdelivery.pdf More Documents & Publications ITP Metal Casting: Advanced Melting Technologies: Energy Saving Concepts and Opportunities for the...

  3. Energy-Efficient Melting and Direct Delivery of High Quality...

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

    radiation and some convec- tion. These furnaces are characterized by poor thermal efficien- cies ranging from approximately 20%-45%. The Energy Efficient Isothermal Melting...

  4. On the scalability of the Albany/FELIX first-order Stokes approximation ice sheet solver for large-scale simulations of the Greenland and Antarctic ice sheets

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

    Tezaur, Irina K.; Tuminaro, Raymond S.; Perego, Mauro; Salinger, Andrew G.; Price, Stephen F.

    2015-01-01

    We examine the scalability of the recently developed Albany/FELIX finite-element based code for the first-order Stokes momentum balance equations for ice flow. We focus our analysis on the performance of two possible preconditioners for the iterative solution of the sparse linear systems that arise from the discretization of the governing equations: (1) a preconditioner based on the incomplete LU (ILU) factorization, and (2) a recently-developed algebraic multigrid (AMG) preconditioner, constructed using the idea of semi-coarsening. A strong scalability study on a realistic, high resolution Greenland ice sheet problem reveals that, for a given number of processor cores, the AMG preconditionermore »results in faster linear solve times but the ILU preconditioner exhibits better scalability. A weak scalability study is performed on a realistic, moderate resolution Antarctic ice sheet problem, a substantial fraction of which contains floating ice shelves, making it fundamentally different from the Greenland ice sheet problem. Here, we show that as the problem size increases, the performance of the ILU preconditioner deteriorates whereas the AMG preconditioner maintains scalability. This is because the linear systems are extremely ill-conditioned in the presence of floating ice shelves, and the ill-conditioning has a greater negative effect on the ILU preconditioner than on the AMG preconditioner.« less

  5. Geol 795 Paleoceanography Ice Sheet Dynamics and Climate Change

    E-Print Network [OSTI]

    Barranco, Joseph

    Geol 795 ­ Paleoceanography Ice Sheet Dynamics and Climate Change Class Meetings: Tuesday 9 of articles related ice sheet dynamics and the role of ice sheets in past, present, and future climate change ice sheet dynamics and the role of ice sheets in climate change. We will discuss effective ways

  6. Plasma Sprayed Pour Tubes and Other Melt Handling Components for Use in Gas Atomization

    SciTech Connect (OSTI)

    Byrd, David; Rieken, Joel; Heidloff, Andy; Besser, Matthew; Anderson, Iver

    2011-04-01

    Ames Laboratory has successfully used plasma sprayed ceramic components made from yttria stabilized zirconia as melt pouring tubes for gas atomization for many years. These tubes have proven to be strong, thermal shock resistant and versatile. Various configurations are possible both internally and externally. Accurate dimensions are achieved internally with a machined fugitive graphite mandrel and externally by diamond grinding. The previous study of the effect of spray parameters on density was extended to determine the effect of the resulting density on the thermal shock characteristics on down-quenching and up-quenching. Encouraging results also prompted investigation of the use of plasma spraying as a method to construct a melt pour exit stopper that is mechanically robust, thermal shock resistant, and not susceptible to attack by reactive melt additions. The Ames Laboratory operates two close-coupled high pressure gas atomizers. These two atomizers are designed to produce fine and coarse spherical metal powders (5{mu} to 500{mu} diameter) of many different metals and alloys. The systems vary in size, but generally the smaller atomizer can produce up to 5 kg of powder whereas the larger can produce up to 25 kg depending on the charge form and density. In order to make powders of such varying compositions, it is necessary to have melt systems capable of heating and containing the liquid charge to the desired superheat temperature prior to pouring through the atomization nozzle. For some metals and alloys this is not a problem; however for some more reactive and/or high melting materials this can pose unique challenges. Figure 1 is a schematic that illustrates the atomization system and its components.

  7. IceT users' guide and reference.

    SciTech Connect (OSTI)

    Moreland, Kenneth D.

    2011-01-01

    The Image Composition Engine for Tiles (IceT) is a high-performance sort-last parallel rendering library. In addition to providing accelerated rendering for a standard display, IceT provides the unique ability to generate images for tiled displays. The overall resolution of the display may be several times larger than any viewport that may be rendered by a single machine. This document is an overview of the user interface to IceT.

  8. In situ cosmogenic radiocarbon production and 2-D ice flow line modeling for an Antarctic blue ice area

    E-Print Network [OSTI]

    Severinghaus, Jeffrey P.

    In situ cosmogenic radiocarbon production and 2-D ice flow line modeling for an Antarctic blue ice; accepted 12 April 2012; published 24 May 2012. [1] Radiocarbon measurements at ice margin sites and blue and 2-D ice flow line modeling for an Antarctic blue ice area, J. Geophys. Res., 117, F02029, doi:10

  9. BISICLES Captures Details of Retreating Antarctic Ice

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

    software framework, and linked them to the existing Community Ice Sheet Model code (CISM). With AMR, researchers can now model dynamic points of interest at extremely high...

  10. The Next ICE Age | Department of Energy

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

    More Documents & Publications The Next ICE Age Fuel Modification t Facilitate Future Combustion Regimes? Optimization of Advanced Diesel Engine Combustion Strategies...

  11. The Stability of the Greenland Ice Sheet

    E-Print Network [OSTI]

    Biasutti, Michela

    , distribution and seasonality · Solid Earth: · Geothermal heatflux Abrupt Climate Change Studies Symposium 21 Rebound (GIA) GPS stations measure vertical deformation of solid Earth as ice

  12. Viscosity of interfacial water regulates ice nucleation

    SciTech Connect (OSTI)

    Li, Kaiyong; Chen, Jing; Zhang, Qiaolan; Zhang, Yifan; University of Chinese Academy of Sciences, Beijing 100049 ; Xu, Shun; Zhou, Xin; Cui, Dapeng; Wang, Jianjun Song, Yanlin

    2014-03-10

    Ice formation on solid surfaces is an important phenomenon in many fields, such as cloud formation and atmospheric icing, and a key factor for applications in preventing freezing. Here, we report temperature-dependent nucleation rates of ice for hydrophilic and hydrophobic surfaces. The results show that hydrophilic surface presents a lower ice nucleation rate. We develop a strategy to extract the thermodynamic parameters, J{sub 0} and ?, in the context of classical nucleation theory. From the extracted J{sub 0} and ?, we reveal the dominant role played by interfacial water. The results provide an insight into freezing mechanism on solid surfaces.

  13. Mathematics Of Ice To Aid Global Warming Forecasts Mathematics Of Ice To Aid Global Warming Forecasts

    E-Print Network [OSTI]

    Golden, Kenneth M.

    Mathematics Of Ice To Aid Global Warming Forecasts Mathematics Of Ice To Aid Global Warming forecasts of how global warming will affect polar icepacks. See also: Earth & Climate q Global Warming q the effects of climate warming, and its presence greatly reduces solar heating of the polar oceans." "Sea ice

  14. Relationship between ice water content and equivalent radar reflectivity for clouds consisting of nonspherical ice particles

    E-Print Network [OSTI]

    Baum, Bryan A.

    Relationship between ice water content and equivalent radar reflectivity for clouds consisting investigates the relationship between ice water content (IWC) and equivalent radar reflectivity (Ze) at 94 GHz. Baum, and A. J. Heymsfield (2008), Relationship between ice water content and equivalent radar

  15. A New Approach for Exploring Ice Sheets and Sub-Ice Geology

    E-Print Network [OSTI]

    Kristoffersen, Yngve

    A New Approach for Exploring Ice Sheets and Sub-Ice Geology Active seismic measurements were geology driven by ice flow [Smith et al., 2007] and the long record of seismic exploration of subglacial sur- veys because of the considerable logistical effort necessary for seismic data acquisition

  16. Satellite SAR Remote Sensing of Great Lakes Ice Cover, Part 2. Ice Classification and Mapping

    E-Print Network [OSTI]

    (look-up table) for different ice types. The library is used in the computer classifica- tion (freshwater) ice types using the Jet Propulsion Laboratory C-band scatterometer, together with surface data set, composed of over 20 variations of different ice types measured at incident angles from 0

  17. Melt Infiltrated Ceramic Composites (Hipercomp) for Gas Turbine Engine Applications

    SciTech Connect (OSTI)

    Gregory Corman; Krishan Luthra

    2005-09-30

    This report covers work performed under the Continuous Fiber Ceramic Composites (CFCC) program by GE Global Research and its partners from 1994 through 2005. The processing of prepreg-derived, melt infiltrated (MI) composite systems based on monofilament and multifilament tow SiC fibers is described. Extensive mechanical and environmental exposure characterizations were performed on these systems, as well as on competing Ceramic Matrix Composite (CMC) systems. Although current monofilament SiC fibers have inherent oxidative stability limitations due to their carbon surface coatings, the MI CMC system based on multifilament tow (Hi-Nicalon ) proved to have excellent mechanical, thermal and time-dependent properties. The materials database generated from the material testing was used to design turbine hot gas path components, namely the shroud and combustor liner, utilizing the CMC materials. The feasibility of using such MI CMC materials in gas turbine engines was demonstrated via combustion rig testing of turbine shrouds and combustor liners, and through field engine tests of shrouds in a 2MW engine for >1000 hours. A unique combustion test facility was also developed that allowed coupons of the CMC materials to be exposed to high-pressure, high-velocity combustion gas environments for times up to {approx}4000 hours.

  18. Low-melting point heat transfer fluid

    DOE Patents [OSTI]

    Cordaro, Joseph G. (Oakland, CA); Bradshaw, Robert W. (Livermore, CA)

    2011-04-12

    A low-melting point, heat transfer fluid comprising a mixture of LiNO.sub.3, NaNO.sub.3, KNO.sub.3, NaNO.sub.2 and KNO.sub.2 salts where the Li, Na and K cations are present in amounts of about 20-33.5 mol % Li, about 18.6-40 mol % Na, and about 40-50.3 mol % K and where the nitrate and nitrite anions are present in amounts of about 36-50 mol % NO.sub.3, and about 50-62.5 mol % NO.sub.2. These compositions can have liquidus temperatures between 70.degree. C. and 80.degree. C. for some compositions.

  19. Melting Alpine Glaciers Enrich High-Elevation Lakes with Reactive

    E-Print Network [OSTI]

    Wolfe, Alexander P.

    melt alone (SF lakes) and those fed by both glacial and snowpack meltwaters (GSF lakes). We foundMelting Alpine Glaciers Enrich High-Elevation Lakes with Reactive Nitrogen J A S M I N E E . S A R century in many regions of the world. Resulting changes in glacial runoff not only affect the hydrological

  20. DNA Melting in the Presence of Fluorescent Intercalating

    E-Print Network [OSTI]

    Fygenson, Deborah Kuchnir

    absorption characteristics that complicate conventional uv measurements of DNA melting. In this article, we was designed to be complementary to uv absorption measurements in that it reports the number of melted duplexes, Vol. 65, 40­44 (2002) © 2002 Wiley Periodicals, Inc. 40 #12;conventional uv absorption measurements

  1. Evaluation of Cloud-Resolving Model Intercomparison Simulations Using TWP-ICE Observations: Precipitation and Cloud Structure

    SciTech Connect (OSTI)

    Varble, Adam; Fridlind, Ann; Zipser, Edward J.; Ackerman, Andrew; Chaboureau, Jean-Pierre; Fan, Jiwen; Hill, Adrian; McFarlane, Sally A.; Pinty, Jean-Pierre; Shipway, Ben

    2011-10-04

    The Tropical Warm Pool – International Cloud Experiment (TWP-ICE) provided high quality model forcing and observational datasets through which detailed model and observational intercomparisons could be performed. In this first of a two part study, precipitation and cloud structures within nine cloud-resolving model simulations are compared with scanning radar reflectivity and satellite infrared brightness temperature observations during an active monsoon period from 19 to 25 January 2006. Most simulations slightly overestimate volumetric convective rainfall. Overestimation of simulated convective area by 50% or more in several simulations is somewhat offset by underestimation of mean convective rain rates. Stratiform volumetric rainfall is underestimated by 13% to 53% despite overestimation of stratiform area by up to 65% because stratiform rain rates in every simulation are much lower than observed. Although simulations match the peaked convective radar reflectivity distribution at low levels, they do not reproduce the peaked distributions observed above the melting level. Simulated radar reflectivity aloft in convective regions is too high in most simulations. In stratiform regions, there is a large spread in model results with none resembling observed distributions. Above the melting level, observed radar reflectivity decreases more gradually with height than simulated radar reflectivity. A few simulations produce unrealistically uniform and cold 10.8-?m infrared brightness temperatures, but several simulations produce distributions close to observed. Assumed ice particle size distributions appear to play a larger role than ice water contents in producing incorrect simulated radar reflectivity distributions aloft despite substantial differences in mean graupel and snow water contents across models.

  2. Intertemporal Computable Equilibrium System (ICES) | Open Energy

    Open Energy Info (EERE)

    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 Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas: Energy ResourcesOrder at 8, 13Renewable PowerMismatch | Open Energy

  3. A direct evidence of vibrationally delocalized response at ice surface

    SciTech Connect (OSTI)

    Ishiyama, Tatsuya; Morita, Akihiro

    2014-11-14

    Surface-specific vibrational spectroscopic responses at isotope diluted ice and amorphous ice are investigated by molecular dynamics (MD) simulations combined with quantum mechanics/molecular mechanics calculations. The intense response specific to the ordinary crystal ice surface is predicted to be significantly suppressed in the isotopically diluted and amorphous ices, demonstrating the vibrational delocalization at the ordinary ice surface. The collective vibration at the ice surface is also analyzed with varying temperature by the MD simulation.

  4. Experimental study of slab solar collection on the hydronic system of road

    SciTech Connect (OSTI)

    Gao, Qing; Huang, Yong; Li, Ming; Liu, Yan [Jilin University, Changchun (China); Yan, Y.Y. [University of Nottingham (United Kingdom)

    2010-12-15

    This paper studied the slab solar collection (SSC) process, which is one of the essential compositions of road hydronic ice-snow melting (HISM) system that stores solar energy in summer to melt ice and snow on the road in winter. Its aim is to find out the heat transfer characteristic of the SSC and heat collecting efficiency and the influence of pipe spacing and flow rate by experiment. As shown in experimental results, the average heat collecting capacity is about 150-250 W/m{sup 2} in natural summer condition, while the solar radiation intensity is about 300-1000 W/m{sup 2}. It is shown that the increment of fluid flow results in the increment of heat collection efficiency, while the increment of pipe spacing results in the decrement of the efficiency in experiment modes. The results show that the road slab can obtain about 30% solar heat in summertime, and the solar collection can lower the pavement temperature and reduce the insolation weathering. (author)

  5. ARM - TWP-ICE Maps

    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, AlaskaManus Site-Inactive TWP Related Links Facilities andTWP-ICE Maps

  6. IceCube at NERSC

    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 Home Room NewsInformation CurrentHenry Bellamy, Ph.D.FoodHydropower,Principal InvestigatorsIceCube at

  7. Results from IceCube/IceTop Ooty, 17/12/12 Tom Gaisser for the IceCube Collab. 1

    E-Print Network [OSTI]

    Gaisser, Thomas K.

    , 17/12/12 Tom Gaisser for the IceCube Collab. 3 #12;Mumbai, 11/12/12 Tom;Mumbai, 11/12/12 Tom Gaisser for the IceCube Collab. 5 DetecMng neutrinos in H of interac,ons IceTop #12;Mumbai, 11/12/12 Tom Gaisser for the IceCube Collab. 6

  8. Radar attenuation and temperature within the Greenland Ice Sheet

    E-Print Network [OSTI]

    2015-01-01

    on obliquely propagating radio waves, IEEE Trans. Geosci.dielectric attenuation of radio waves through ice is alsoattenuation of radio waves through ice is also temperature

  9. ICR-ICE Standard Operating Procedures (Update Sept 2013) | Department...

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

    ICR-ICE Standard Operating Procedures (Update Sept 2013) ICR-ICE Standard Operating Procedures (Update Sept 2013) ICRICE SOPSep 2013Final.pdf More Documents & Publications...

  10. Rapid development of an ice sheet climate application using the...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Rapid development of an ice sheet climate application using the components-based approach Citation Details In-Document Search Title: Rapid development of an ice...

  11. Cosmic-ray results from IceCube/ Mumbai, 12/12/12 Tom Gaisser for the IceCube Collab. 1

    E-Print Network [OSTI]

    Gaisser, Thomas K.

    Cosmic-ray results from IceCube/ IceTop Mumbai, 12/12/12 Tom Gaisser for the IceCube Collab. 1 #12;Mumbai, 12/12/12 Tom Gaisser for the IceCube Collab. 2 events ­ IceTop/deep IceCube Mumbai, 12/12/12 Tom Gaisser for the IceCube Collab

  12. Ice Cover on the Great Lakes NATIONALOCEANIC

    E-Print Network [OSTI]

    : In the shallow waters where whitefish spawn, ice cover protects their eggs from destructive wind and wave action://coastwatch.glerl.noaa.gov/glsea/cur/glsea_cur.png #12;GLERL Research Forecast capability The capability to forecast and predict ice cover is important for recreational safety and rescue efforts as well as for navigation, weather forecasting, adapting to lake level

  13. Total reflection infrared spectroscopy of water-ice and frozen aqueous NaCl solutions

    SciTech Connect (OSTI)

    Walker, Rachel L.; Searles, Keith; Willard, Jesse A.; Michelsen, Rebecca R. H., E-mail: RMichelsen@rmc.edu [Department of Chemistry, Randolph-Macon College, P.O. Box 5005, Ashland, Virginia 23005 (United States)] [Department of Chemistry, Randolph-Macon College, P.O. Box 5005, Ashland, Virginia 23005 (United States)

    2013-12-28

    Liquid-like and liquid water at and near the surface of water-ice and frozen aqueous sodium chloride films were observed using attenuated total reflection infrared spectroscopy (ATR-IR). The concentration of NaCl ranged from 0.0001 to 0.01 M and the temperature varied from the melting point of water down to 256 K. The amount of liquid brine at the interface of the frozen films with the germanium ATR crystal increased with salt concentration and temperature. Experimental spectra are compared to reflection spectra calculated for a simplified morphology of a uniform liquid layer between the germanium crystal and the frozen film. This morphology allows for the amount of liquid observed in an experimental spectrum to be converted to the thickness of a homogenous layer with an equivalent amount of liquid. These equivalent thickness ranges from a nanometer for water-ice at 260 K to 170 nm for 0.01 M NaCl close to the melting point. The amounts of brine observed are over an order of magnitude less than the total liquid predicted by equilibrium thermodynamic models, implying that the vast majority of the liquid fraction of frozen solutions may be found in internal inclusions, grain boundaries, and the like. Thus, the amount of liquid and the solutes dissolved in them that are available to react with atmospheric gases on the surfaces of snow and ice are not well described by thermodynamic equilibrium models which assume the liquid phase is located entirely at the surface.

  14. Flow-History-Dependent Behavior in Entangled Polymer Melt Flow with Multiscale Simulation

    E-Print Network [OSTI]

    Takahiro Murashima; Takashi Taniguchi

    2011-10-05

    Polymer melts represent the flow-history-dependent behavior. To clearly show this behavior, we have investigated flow behavior of an entangled polymer melt around two cylinders placed in tandem along the flow direction in a two dimensional periodic system. In this system, the polymer states around a cylinder in downstream side are different from the ones around another cylinder in upstream side because the former ones have a memory of a strain experienced when passing around the cylinder in upstream side but the latter ones do not have the memory. Therefore, the shear stress distributions around two cylinders are found to be different from each other. Moreover, we have found that the averaged flow velocity decreases accordingly with increasing the distance between two cylinders while the applied external force is constant. While this behavior is consistent with that of the Newtonian fluid, the flow-history-dependent behavior enhances the reduction of the flow resistance.

  15. Numerical study of a slip-link model for polymer melts and nanocomposites

    E-Print Network [OSTI]

    Diego Delbiondo; Elian Masnada; Samy Merabia; Marc Couty; Jean-Louis Barrat

    2013-06-10

    We present a numerical study of the slip link model introduced by Likhtman for describing the dy- namics of dense polymer melts. After reviewing the technical aspects associated with the implemen- tation of the model, we extend previous work in several directions. The dependence of the relaxation modulus with the slip link density and the slip link stiffness is reported. Then the nonlinear rheolog- ical properties of the model, for a particular set of parameters, are explored. Finally, we introduce excluded volume interactions in a mean field such as manner in order to describe inhomogeneous systems, and we apply this description to a simple nanocomposite model. With this extension, the slip link model appears as a simple and generic model of a polymer melt, that can be used as an alternative to molecular dynamics for coarse grained simulations of complex polymeric systems.

  16. A parallel high-order accurate finite element nonlinear Stokes ice sheet model and benchmark experiments

    SciTech Connect (OSTI)

    Leng, Wei [Chinese Academy of Sciences; Ju, Lili [University of South Carolina; Gunzburger, Max [Florida State University; Price, Stephen [Los Alamos National Laboratory; Ringler, Todd [Los Alamos National Laboratory,

    2012-01-01

    The numerical modeling of glacier and ice sheet evolution is a subject of growing interest, in part because of the potential for models to inform estimates of global sea level change. This paper focuses on the development of a numerical model that determines the velocity and pressure fields within an ice sheet. Our numerical model features a high-fidelity mathematical model involving the nonlinear Stokes system and combinations of no-sliding and sliding basal boundary conditions, high-order accurate finite element discretizations based on variable resolution grids, and highly scalable parallel solution strategies, all of which contribute to a numerical model that can achieve accurate velocity and pressure approximations in a highly efficient manner. We demonstrate the accuracy and efficiency of our model by analytical solution tests, established ice sheet benchmark experiments, and comparisons with other well-established ice sheet models.

  17. Assessment of ceramic coatings for metal fuel melting crucible

    SciTech Connect (OSTI)

    Kim, Ki-Hwan; Song, Hoon; Kim, Jong-Hwan; Oh, Seok-Jin; Kim, Hyung-Tae; Lee, Chan-Bock

    2013-07-01

    The objective of this study is to develop a coating method and material for crucibles to prevent material interactions with the U-Zr/U-TRU-Zr fuels during the manufacturing of SFR fuels. Refractory coatings were applied to niobium substrates by vacuum plasma-spray coating method. Melt dipping tests conducted were the coated rods lowered into the fuel melt at 1600 C. degrees, and withdrawn and cooled outside the crucible in the inert atmosphere of the induction furnace. Melt dipping tests of the coated Nb rods indicated that plasma-sprayed Y{sub 2}O{sub 3} coating doesn't form significant reaction layer between fuel melt and coating layer. Melt dipping tests of the coated Nb rods showed that TiC, TaC, and Y{sub 2}O{sub 3} coatings exhibited the promising performance among other ceramic coatings. These materials could be promising candidate materials for the reusable melt crucible of metal fuel for SFR. In addition, in order to develop the vacuum plasma-spray coating method for re-usable crucible of metal fuel slugs to be overcome the issue of thermal expansion mismatch between coating material and crucible, various combinations of coating conditions were investigated to find the bonding effect on the substrate in pursuit of more effective ways to withstand the thermal stresses. It is observed that most coating methods maintained sound coating state in U-Zr melt. (authors)

  18. Melt zones beneath five volcanic complexes in California: an assessment of shallow magma occurrences

    SciTech Connect (OSTI)

    Goldstein, N.E.; Flexser, S.

    1984-12-01

    Recent geological and geophysical data for five magma-hydrothermal systems were studied for the purpose of developing estimates for the depth, volume and location of magma beneath each area. The areas studied were: (1) Salton Trough, (2) The Geysers-Clear Lake, (3) Long Valley caldera, (4) Coso volcanic field, and (5) Medicine Lake volcano, all located in California and all selected on the basis of recent volcanic activity and published indications of crustal melt zones. 23 figs.

  19. MELTING OF GLASS BATCH: MODEL FOR MULTIPLE OVERLAPPING GAS-EVOLVING...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: MELTING OF GLASS BATCH: MODEL FOR MULTIPLE OVERLAPPING GAS-EVOLVING REACTIONS Citation Details In-Document Search Title: MELTING OF GLASS BATCH: MODEL FOR MULTIPLE...

  20. Geek-Up: K East Reactor Demolition, Retrograde Melting and Cloud Pattern Tracking

    Broader source: Energy.gov [DOE]

    Recovery Act funds help clean up the Hanford site, retrograde melting (melting as something cools) and how open-cell clouds could help predict climate change.

  1. Exploration of Melt Spinning as a Route to Large Volume Production...

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

    Exploration of Melt Spinning as a Route to Large Volume Production of Skutterudite Thermoelectric Materials Exploration of Melt Spinning as a Route to Large Volume Production of...

  2. String melting in a photon bath

    SciTech Connect (OSTI)

    Karouby, Johanna, E-mail: karoubyj@mit.edu [Center for Theoretical Physics and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachussetts 02139 (United States)

    2013-10-01

    We compute the decay rate of a metastable cosmic string in contact with a thermal bath by finding the instanton solution. The new feature is that this decay rate is found in the context of non thermal scalar fields in contact with a thermal bath of photons. In general, to make topologically unstable strings stable, one can couple them to such a bath. The resulting plasma effect creates metastable configurations which can decay from the false vacuum to the true vacuum. In our specific set-up, the instanton computation is realized for the case of two out-of-equilibrium complex scalar fields: one is charged and coupled to the photon field, and the other is neutral. New effects coming from the thermal bath of photons make the radius of the nucleated bubble and most of the relevant physical quantities temperature-dependent. However, the temperature appears in a different way than in the purely thermal case, where all scalar fields are in thermal equilibrium. As a result of the tunneling, the core of the initial string melts while bubbles of true vacuum expand at the speed of light.

  3. Hybrid Dynamic Density Functional Theory for Polymer Melts and Blends

    E-Print Network [OSTI]

    Takashi Honda; Toshihiro Kawakatsu

    2006-09-05

    We propose a high-speed and accurate hybrid dynamic density functional theory for the computer simulations of the phase separation processes of polymer melts and blends. The proposed theory is a combination of the dynamic self-consistent field (SCF) theory and a time-dependent Ginzburg-Landau type theory with the random phase approximation (GRPA). The SCF theory is known to be accurate in evaluating the free energy of the polymer systems in both weak and strong segregation regions although it has a disadvantage of the requirement of a considerable amount of computational cost. On the other hand, the GRPA theory has an advantage of much smaller amount of required computational cost than the SCF theory while its applicability is limited to the weak segregation region. To make the accuracy of the SCF theory and the high-performance of the GRPA theory compatible, we adjust the chemical potential of the GRPA theory by using the SCF theory every constant time steps in the dynamic simulations. The performance of the GRPA and the hybrid theories is tested by using several systems composed of an A/B homopolymer, an AB diblock copolymer, or an ABC triblock copolymer. Using the hybrid theory, we succeeded in reproducing the metastable complex phase-separated domain structures of an ABC triblock copolymer observed by experiments.

  4. Hydrogen Fuel Pilot Plant and Hydrogen ICE Vehicle Testing

    SciTech Connect (OSTI)

    J. Francfort (INEEL)

    2005-03-01

    The U.S. Department Energy's Advanced Vehicle Testing Activity (AVTA) teamed with Electric Transportation Applications (ETA) and Arizona Public Service (APS) to develop the APS Alternative Fuel (Hydrogen) Pilot Plant that produces and compresses hydrogen on site through an electrolysis process by operating a PEM fuel cell in reverse; natural gas is also compressed onsite. The Pilot Plant dispenses 100% hydrogen, 15 to 50% blends of hydrogen and compressed natural gas (H/CNG), and 100% CNG via a credit card billing system at pressures up to 5,000 psi. Thirty internal combustion engine (ICE) vehicles (including Daimler Chrysler, Ford and General Motors vehicles) are operating on 100% hydrogen and 15 to 50% H/CNG blends. Since the Pilot Plant started operating in June 2002, they hydrogen and H/CNG ICE vehicels have accumulated 250,000 test miles.

  5. Method for Synthesizing Extremeley High Temperature Melting Materials

    DOE Patents [OSTI]

    Saboungi, Marie-Louise and Glorieux, Benoit

    2005-11-22

    The invention relates to a method of synthesizing high-temperature melting materials. More specifically the invention relates to a containerless method of synthesizing very high temperature melting materials such as borides, carbides and transition-metal, lanthanide and actinide oxides, using an Aerodynamic Levitator and a laser. The object of the invention is to provide a method for synthesizing extremely high-temperature melting materials that are otherwise difficult to produce, without the use of containers, allowing the manipulation of the phase (amorphous/crystalline/metastable) and permitting changes of the environment such as different gaseous compositions.

  6. Method for synthesizing extremely high-temperature melting materials

    DOE Patents [OSTI]

    Saboungi, Marie-Louise (Chicago, IL); Glorieux, Benoit (Perpignan, FR)

    2007-11-06

    The invention relates to a method of synthesizing high-temperature melting materials. More specifically the invention relates to a containerless method of synthesizing very high temperature melting materials such as carbides and transition-metal, lanthanide and actinide oxides, using an aerodynamic levitator and a laser. The object of the invention is to provide a method for synthesizing extremely high-temperature melting materials that are otherwise difficult to produce, without the use of containers, allowing the manipulation of the phase (amorphous/crystalline/metastable) and permitting changes of the environment such as different gaseous compositions.

  7. Method For Synthesizing Extremely High-Temperature Melting Materials

    DOE Patents [OSTI]

    Saboungi, Marie-Louise (Chicago, IL); Glorieux, Benoit (Perpignan, FR)

    2005-11-22

    The invention relates to a method of synthesizing high-temperature melting materials. More specifically the invention relates to a containerless method of synthesizing very high temperature melting materials such as borides, carbides and transition-metal, lanthanide and actinide oxides, using an Aerodynamic Levitator and a laser. The object of the invention is to provide a method for synthesizing extremely high-temperature melting materials that are otherwise difficult to produce, without the use of containers, allowing the manipulation of the phase (amorphous/crystalline/metastable) and permitting changes of the environment such as different gaseous compositions.

  8. Remote sensing of seawater and drifting ice in Svalbard fjords by compact Raman LIDAR

    E-Print Network [OSTI]

    Bunkin, Alexey F; Lednev, Vasily N; Lushnikov, Dmitry L; Marchenko, Aleksey V; Morozov, Eugene G; Pershin, Sergey M; Yulmetov, Renat N

    2013-01-01

    A compact Raman LIDAR system for remote sensing of sea and drifting ice was developed at the Wave Research Center at the Prokhorov General Physics Institute of the RAS. The developed system is based on a diode pumped solid state YVO4:Nd laser combined with compact spectrograph equipped with gated detector. The system exhibits high sensitivity and can be used for mapping or depth profiling of different parameters within many oceanographic problems. Light weight (~20 kg) and low power consumption (300 W) make possible to install the device on any vehicle including unmanned aircraft or submarine system. The Raman LIDAR presented was used for Svalbard fjords study and analysis of different influence of the open sea and glaciers on the water properties. Temperature, phytoplankton, and dissolved organic matter distributions in the seawater were studied in the Ice Fjord, Van Mijen Fjord and Rinders Fjord. Drifting ice and seawater in the Rinders Fjord were characterized by the Raman spectroscopy and fluorescence. It...

  9. Remote sounding of Greenland supraglacial melt lakes: implications for subglacial hydraulics

    E-Print Network [OSTI]

    Box, Jason E.

    to Greenland ice-sheet flow may be a feedback between abrupt lake drainage events and ice dynamics. Lake to lift the ice sheet locally, if water flow in the subglacial environment is constrained laterally

  10. NEW INSIGHT ON THE ORIGIN OF SPIRAL TROUGHS IN MARTIAN POLAR ICE CAPS. Zuoxun Zeng1,2,3,4

    E-Print Network [OSTI]

    Texas at San Antonio, University of

    of the Lecture of Geomechanics, From [9]). This is similar to the spiral trough system in the Martian polar ice the writing group of the Lecture of Geomechanics, 1972, From [9]) Analytic solution for the stress field

  11. The interaction of radio frequency electromagnetic fields with atmospheric water droplets and application to aircraft ice prevention

    E-Print Network [OSTI]

    Hansman, Robert John

    1982-01-01

    In this work the physics of advanced microwave anti-icing systems, which pre-heat impinging supercooled water droplets prior to impact, is studied by means of a computer simulation and is found to be feasible. In order to ...

  12. Radiostratigraphy and age structure of the Greenland Ice Sheet

    E-Print Network [OSTI]

    2015-01-01

    is 3.15, equivalent to a radio-wave velocity in ice of 168.9to be vertical) that a radio wave travels through ice during?t is where v ice is the radio-wave velocity in ice, ?z ¼ v

  13. Crystalline water ice on the Kuiper belt object (50000) Quaoar

    E-Print Network [OSTI]

    Jewitt, David C.

    .............................................................. Crystalline water ice on the Kuiper the presence of crystalline water ice and ammonia hydrate. Crystallinity indicates that the ice has been heated to at least 110 K. Both ammonia hydrate and crystalline water ice should be destroyed by energetic particle

  14. Melt generation in the Earth's mantle at Convergent Plate Margins

    E-Print Network [OSTI]

    Till, Christy B

    2011-01-01

    The five geologic studies presented in this thesis document how the recycling of tectonic plates at subduction zones has a profound effect on the melting behavior of the Earth's mantle. Two experimental studies (Chapters ...

  15. Effect of Alumina Source on the Rate of Melting Demonstrated...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Effect of Alumina Source on the Rate of Melting Demonstrated with Nuclear Waste Glass Batch Citation Details In-Document Search Title: Effect of Alumina Source on...

  16. Building Icelandic Igneous Crust by Repeated Melt Injections

    E-Print Network [OSTI]

    Greenfield, Tim; White, Robert S.

    2015-10-27

    Observations of microseismicity provide a powerful tool for mapping the movement of melt in the crust. Here we record remarkable sequences of earthquakes 20 km below the surface in the normally ductile crust in the vicinity of Askja volcano...

  17. Melt extrusion and continuous manufacturing of pharmaceutical materials

    E-Print Network [OSTI]

    Bell, Erin R

    2011-01-01

    Melt extrusion is an alternative processing technique that operates continuously, reduces the total number of unit operations, allows for incorporation of difficult-to-process drug substances, and has the potential to ...

  18. Molecular simulations of heterogeneous ice nucleation. I. Controlling ice nucleation through surface hydrophilicity

    E-Print Network [OSTI]

    Stephen J. Cox; Shawn M. Kathmann; Ben Slater; Angelos Michaelides

    2015-05-29

    Ice formation is one of the most common and important processes on earth and almost always occurs at the surface of a material. A basic understanding of how the physicochemical properties of a material's surface affect its ability to form ice has remained elusive. Here, we use molecular dynamics simulations to directly probe heterogeneous ice nucleation at a hexagonal surface of a nanoparticle of varying hydrophilicity. Surprisingly, we find that structurally identical surfaces can both inhibit and promote ice formation and analogous to a chemical catalyst, it is found that an optimal interaction between the surface and the water exists for promoting ice nucleation. We use our microscopic understanding of the mechanism to design a modified surface in silico with enhanced ice nucleating ability.

  19. Chapter 1 x Introduction 63 C1.2 When a person ice-skates, the ice surface actually melts beneath the blades, so

    E-Print Network [OSTI]

    Bahrami, Majid

    100 kg, L 30 cm, W 5 mm, and h 0.1 mm. Do you think our assumption of negligible air resistance! It appears that our assumption of negligible air drag was grossly incorrect. C1.3 Two thin flat plates)] Ans. (b) C1.4 Oil of viscosity P and density U drains steadily down the side of a tall, wide vertical

  20. Method and apparatus for melt growth of crystalline semiconductor sheets

    DOE Patents [OSTI]

    Ciszek, T.F.; Hurd, J.L.

    1981-02-25

    An economical method is presented for forming thin sheets of crystalline silicon suitable for use in a photovoltaic conversion cell by solidification from the liquid phase. Two spatially separated, generally coplanar filaments wettable by liquid silicon and joined together at the end by a bridge member are immersed in a silicon melt and then slowly withdrawn from the melt so that a silicon crystal is grown between the edge of the bridge and the filaments.

  1. Apparatus for melt growth of crystalline semiconductor sheets

    DOE Patents [OSTI]

    Ciszek, Theodore F. (Evergreen, CO); Hurd, Jeffery L. (Golden, CO)

    1986-01-01

    An economical method is presented for forming thin sheets of crystalline silicon suitable for use in a photovoltaic conversion cell by solidification from the liquid phase. Two spatially separated, generally coplanar filaments wettable by liquid silicon and joined together at the end by a bridge member are immersed in a silicon melt and then slowly withdrawn from the melt so that a silicon crystal is grown between the edge of the bridge and the filaments.

  2. Self-Consistent-Field Study of Adsorption and Desorption Kinetics of Polyethylene Melts on Graphite and Comparison with Atomistic Simulations

    E-Print Network [OSTI]

    Doros N. Theodorou; Georgios G. Vogiatzis; Georgios Kritikos

    2015-02-20

    A method is formulated, based on combining self-consistent field theory with dynamically corrected transition state theory, for estimating the rates of adsorption and desorption of end-constrained chains (e.g. by crosslinks or entanglements) from a polymer melt onto a solid substrate. This approach is tested on a polyethylene/graphite system, where the whole methodology is parametrized by atomistically detailed molecular simulations. For short-chain melts, which can still be addressed by molecular dynamics simulations with reasonable computational resources, the self-consistent field approach gives predictions of the adsorption and desorption rate constants which are gratifyingly close to molecular dynamics estimates.

  3. A Smoothed Particle Hydrodynamics Model for Ice Sheet and Ice Shelf Dynamics

    SciTech Connect (OSTI)

    Pan, Wenxiao; Tartakovsky, Alexandre M.; Monaghan, Joseph J.

    2012-02-08

    Mathematical modeling of ice sheets is complicated by the non-linearity of the governing equations and boundary conditions. Standard grid-based methods require complex front tracking techniques and have limited capability to handle large material deformations and abrupt changes in bottom topography. As a consequence, numerical methods are usually restricted to shallow ice sheet and ice shelf approximations. We propose a new smoothed particle hydrodynamics (SPH) model for coupled ice sheet and ice shelf dynamics. SPH is a fully Lagrangian particle method. It is highly scalable and its Lagrangian nature and meshless discretization are well suited to the simulation of free surface flows, large material deformation, and material fragmentation. In this paper SPH is used to study ice sheet/ice shelf behavior, and the dynamics of the grounding line. The steady state position of the grounding line obtained from the SPH simulations is in good agreement with laboratory observations for a wide range of simulated bedrock slopes, and density ratios similar to those of ice and sea water. The numerical accuracy of the SPH algorithm is further verified by simulating the plane shear flow of two immiscible fluids and the propagation of a highly viscous blob of fluid along a horizontal surface. In the experiment, the ice was represented with a viscous newtonian fluid. For consistency, in the described SPH model the ice is also modeled as a viscous newtonian fluid. Typically, ice sheets are modeled as a non-Newtonian fluid, accounting for the changes in the mechanical properties of ice. Implementation of a non-Newtonian rheology in the SPH model is the subject of our ongoing research.

  4. Smoothed particle hydrodynamics Non-Newtonian model for ice-sheet and ice-shelf dynamics

    SciTech Connect (OSTI)

    Pan, Wenxiao; Tartakovsky, Alexandre M.; Monaghan, Joseph J.

    2013-06-01

    Mathematical modeling of ice sheets is complicated by the non-linearity of the governing equations and boundary conditions. Standard grid-based methods require complex front tracking techniques and have limited capability to handle large material deformations and abrupt changes in bottom topography. As a consequence, numerical methods are usually restricted to shallow ice sheet and ice shelf approximations. We propose a new smoothed particle hydrodynamics (SPH) non-Newtonian model for coupled ice sheet and ice shelf dynamics. SPH, a fully Lagrangian particle method, is highly scalable and its Lagrangian nature and meshless discretization are well suited to the simulation of free surface ?ows, large material deformation, and material fragmentation. In this paper, SPH is used to study 3D ice sheet/ice shelf behavior, and the dynamics of the grounding line. The steady state position of the grounding line obtained from SPH simulations is in good agreement with laboratory observations for a wide range of simulated bedrock slopes, and density ratios, similar to those of ice and sea water. The numerical accuracy of the SPH algorithm is veri?ed by simulating Poiseuille ?ow, plane shear ?ow with free surface and the propagation of a blob of ice along a horizontal surface. In the laboratory experiment, the ice was represented with a viscous Newtonian ?uid. In the present work, however, the ice is modeled as both viscous Newtonian ?uid and non-Newtonian ?uid, such that the e?ect of non-Newtonian rheology on the dynamics of grounding line was examined. The non-Newtonian constitutive relation is prescribed to be Glen’s law for the creep of polycrystalline ice. A V-shaped bedrock ramp is further introduced to model the real geometry of bedrock slope.

  5. Do blue-ice moraines in the Heritage Range show the West Antarctic ice sheet survived the last interglacial?

    E-Print Network [OSTI]

    Do blue-ice moraines in the Heritage Range show the West Antarctic ice sheet survived the last in revised form 10 January 2011 Accepted 28 January 2011 Available online xxxx Keywords: Blue-ice moraine cosmogenic isotope data on blue-ice moraines in the Heritage Range, West Antarctica. The age of the moraines

  6. Inter-annual sea-ice dynamics and micro-algal biomass in winter pack ice of Marguerite Bay, Antarctica

    E-Print Network [OSTI]

    Stewart, Frank

    in this region (Stammerjohn et al., 2003; Stammerjohn and Smith, 1996). Changes in mesoscale ice dynamics

  7. Processes driving sea ice variability in the Bering Sea in an eddying ocean/sea ice model: Mean seasonal cycle

    E-Print Network [OSTI]

    Eisenman, Ian

    the southern ice edge, especially on the western side. The sea ice force balance analysis shows that sea ice air from northerly winds and ice motion away from the coast. South of St Lawrence Island, winds drive is important both climatically and economically. Understanding the processes that control the temporal

  8. High-Pressure Melt Streaming (HIPS) program plan

    SciTech Connect (OSTI)

    Tarbell, W.; Brockmann, J.; Pilch, M.

    1984-08-01

    The Zion Probabilistic Safety Study (ZPSS) envisions accident sequences that could lead to failure of the reactor vessel while the primary system is pressurized. The resulting ejection of molten core material into the reactor cavity followed by the blowdown of steam and hydrogen is shown to cause the debris to enter into the containment region. The High Pressure Melt Streaming (HIPS) program has been developed to provide an experimental and analytical investigation of the scenario described above. One-tenth linear scale models of the Zion cavity region will be used to investigate the debris dispersal phenomena. Smaller-scale experiments (SPIT-tests) are also used to study high-velocity jets, jet-water interactions, and 1/20th scale cavity geometries. Both matrices are developed using a factorial design approach. The document describes certain aspects of the ZPSS ex-vessel phenomena, the experimental matrices, test equipment, and instrumentation, and the program's analytical efforts. Preliminary data from SPIT testing are included.

  9. Communication: On the stability of ice 0, ice i, and I{sub h}

    SciTech Connect (OSTI)

    Quigley, D.; Alfè, D.; Slater, B.

    2014-10-28

    Using ab initio methods, we examine the stability of ice 0, a recently proposed tetragonal form of ice implicated in the homogeneous freezing of water [J. Russo, F. Romano, and H. Tanaka, Nat. Mater. 13, 670 (2014)]. Vibrational frequencies are computed across the complete Brillouin Zone using Density Functional Theory (DFT), to confirm mechanical stability and quantify the free energy of ice 0 relative to ice I{sub h}. The robustness of this result is tested via dispersion corrected semi-local and hybrid DFT, and Quantum Monte-Carlo calculation of lattice energies. Results indicate that popular molecular models only slightly overestimate the stability of ice zero. In addition, we study all possible realisations of proton disorder within the ice zero unit cell, and identify the ground state as ferroelectric. Comparisons are made to other low density metastable forms of ice, suggesting that the ice i structure [C. J. Fennel and J. D. Gezelter, J. Chem. Theory Comput. 1, 662 (2005)] may be equally relevant to ice formation.

  10. Weakening of ice by magnesium perchlorate hydrate

    E-Print Network [OSTI]

    Lenferink, Hendrik J., 1985-

    2012-01-01

    I show that perchlorate hydrates, which have been indirectly detected at high Martian circumpolar latitudes by the Phoenix Mars Lander, have a dramatic effect upon the rheological behavior of polycrystalline water ice under ...

  11. Widespread Excess Ice in Arcadia Planitia, Mars

    E-Print Network [OSTI]

    Bramson, Ali M; Putzig, Nathaniel E; Sutton, Sarah; Plaut, Jeffrey J; Brothers, T Charles; Holt, John W

    2015-01-01

    The distribution of subsurface water ice on Mars is a key constraint on past climate, while the volumetric concentration of buried ice (pore-filling versus excess) provides information about the process that led to its deposition. We investigate the subsurface of Arcadia Planitia by measuring the depth of terraces in simple impact craters and mapping a widespread subsurface reflection in radar sounding data. Assuming that the contrast in material strengths responsible for the terracing is the same dielectric interface that causes the radar reflection, we can combine these data to estimate the dielectric constant of the overlying material. We compare these results to a three-component dielectric mixing model to constrain composition. Our results indicate a widespread, decameters-thick layer that is excess water ice ~10^4 km^3 in volume. The accumulation and long-term preservation of this ice is a challenge for current Martian climate models.

  12. Spreading of oil spilled under ice

    SciTech Connect (OSTI)

    Yapa, P.D.; Chowdhury, T. )

    1990-12-01

    A new set of equations is presented to describe the process of oil spreading under ice in clam waters. These equations consider the gravity (buoyancy)-inertia phase, the gravity (buoyancy)-viscous phase, and the termination of spreading during the buoyancy-surface-tension phase. The derivation considers both the constant discharge mode and the constant volume mode. Therefore, a complete description of the spreading phenomena from the time of initial spill to the termination of spreading is presented. Laboratory experiments were conducted using both real ice covers in a cold room and artificial ice covers. The experiments included different ice-cover roughnesses from smooth to rough, oils of different viscosities, and a variety of discharge conditions. The experimental data show close agreement with the theory. These equations can be used during cleanup or environmental impact assessment to estimate the area of an oil slick with respect to time.

  13. Recent vs from IceCube

    E-Print Network [OSTI]

    Klein, Spencer R.; IceCube Collaboration

    2008-01-01

    in the Sun and the Earth, look for low-energy (10 MeV)Sun. IceTop has made a preliminary measurement of the cosmic-ray energy

  14. Benchmarking the x-ray phase contrast imaging for ICF DT ice characterization using roughened surrogates

    SciTech Connect (OSTI)

    Dewald, E; Kozioziemski, B; Moody, J; Koch, J; Mapoles, E; Montesanti, R; Youngblood, K; Letts, S; Nikroo, A; Sater, J; Atherton, J

    2008-06-26

    We use x-ray phase contrast imaging to characterize the inner surface roughness of DT ice layers in capsules planned for future ignition experiments. It is therefore important to quantify how well the x-ray data correlates with the actual ice roughness. We benchmarked the accuracy of our system using surrogates with fabricated roughness characterized with high precision standard techniques. Cylindrical artifacts with azimuthally uniform sinusoidal perturbations with 100 um period and 1 um amplitude demonstrated 0.02 um accuracy limited by the resolution of the imager and the source size of our phase contrast system. Spherical surrogates with random roughness close to that required for the DT ice for a successful ignition experiment were used to correlate the actual surface roughness to that obtained from the x-ray measurements. When comparing average power spectra of individual measurements, the accuracy mode number limits of the x-ray phase contrast system benchmarked against surface characterization performed by Atomic Force Microscopy are 60 and 90 for surrogates smoother and rougher than the required roughness for the ice. These agreement mode number limits are >100 when comparing matching individual measurements. We will discuss the implications for interpreting DT ice roughness data derived from phase-contrast x-ray imaging.

  15. Changing monsoon patterns, snow and glacial melt, its impacts and adaptation options in northern India: Synthesis

    E-Print Network [OSTI]

    Butler, David R. - Department of Geography, Texas State University

    Editorial Changing monsoon patterns, snow and glacial melt, its impacts and adaptation options of northern India. Flows in such Himalayan rivers are derived from both contemporary precipitation and melting glacier melt, and in warmer drier summers through enhanced melt making up for reduced precipita- tion (e

  16. On the correlation between ice water content and ice crystal size and its application to radiative transfer and general circulation models

    E-Print Network [OSTI]

    Liou, K. N.

    On the correlation between ice water content and ice crystal size and its application to radiative analysis involving ice water content (IWC) and mean effective ice crystal size (De) intended, K. N., Y. Gu, Q. Yue, and G. McFarguhar (2008), On the correlation between ice water content and ice

  17. IceCube: Performance, Status, and Future

    E-Print Network [OSTI]

    Carsten Rott; for the IceCube Collaboration

    2006-11-28

    High-energy neutrinos are uniquely suited to study a large variety of physics as they traverse the universe almost untouched, in contrast to conventional astronomical messengers like photons or cosmic rays which are limited by interactions with radiation and matter at high energies or deflected by ambient magnetic fields. Located at the South Pole, IceCube combined with its predecessor AMANDA comprise the world's largest neutrino telescope. IceCube currently consists of nine strings, each containing 60 digital optical modules, deployed at depths of 1.5 to 2.5km in the ice and an array of 16 surface air-shower stations. IceCube is expected to be completed in early 2011 at which time it will instrument a volume of one km^3 below the IceTop air-shower array covering an area of one km^2. The current IceCube detector performance is described and an outlook given into the large variety of physics that it can address, with an emphasis on the search for ultra-high-energy neutrinos which may shed light on the origins of the highest energy cosmic rays.

  18. IceCube: Performance, Status, and Future

    E-Print Network [OSTI]

    Rott, C

    2006-01-01

    High-energy neutrinos are uniquely suited to study a large variety of physics as they traverse the universe almost untouched, in contrast to conventional astronomical messengers like photons or cosmic rays which are limited by interactions with radiation and matter at high energies or deflected by ambient magnetic fields. Located at the South Pole, IceCube combined with its predecessor AMANDA comprise the world's largest neutrino telescope. IceCube currently consists of nine strings, each containing 60 digital optical modules, deployed at depths of 1.5 to 2.5km in the ice and an array of 16 surface air-shower stations. IceCube is expected to be completed in early 2011 at which time it will instrument a volume of one km^3 below the IceTop air-shower array covering an area of one km^2. The current IceCube detector performance is described and an outlook given into the large variety of physics that it can address, with an emphasis on the search for ultra-high-energy neutrinos which may shed light on the origins ...

  19. Ice chemistry in starless molecular cores

    E-Print Network [OSTI]

    Kalvans, Juris

    2015-01-01

    Starless molecular cores are natural laboratories for interstellar molecular chemistry research. The chemistry of ices in such objects was investigated with a three-phase (gas, surface, and mantle) model. We considered the center part of five starless cores, with their physical conditions derived from observations. The ice chemistry of oxygen, nitrogen, sulfur, and complex organic molecules (COMs) was analyzed. We found that an ice-depth dimension, measured, e.g., in monolayers, is essential for modeling of chemistry in interstellar ices. Particularly, the H2O:CO:CO2:N2:NH3 ice abundance ratio regulates the production and destruction of minor species. It is suggested that photodesorption during core collapse period is responsible for high abundance of interstellar H2O2 and O2H, and other species synthesized on the surface. The calculated abundances of COMs in ice were compared to observed gas-phase values. Smaller activation barriers for CO and H2CO hydrogenation may help explain the production of a number of...

  20. Combustion Technology Development for an Advanced Glass Melting System 

    E-Print Network [OSTI]

    Stickler, D. B.; Westra, L.; Woodroffe, J.; Jeong, K. M.; Donaldson, L. W.

    1987-01-01

    Concept feasibility of an innovative technology for glass production has recently been demonstrated. It is based on suspension heating of the glass-forming batch minerals while entrained in a combustion flow of preheated air and natural gas...

  1. The melting lines of model systems calculated from coexistence simulations

    E-Print Network [OSTI]

    Song, Xueyu

    rapidly as a function of the potential cutoff, indicating that long-range corrections to the free energies of the solid and liquid phases very nearly cancel. This approach provides an alternative to traditional methods them. Tradition- ally, these calculations have been made using free energy calculations: by calculating

  2. Rapid Conditioning for the Next Generation Melting System

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

    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 of Natural GasAdjustmentsShirleyEnergyTher i nAandSummary From: JuliaDepartment-8-2008 October5 of 9ofOn a blustery day

  3. Technology demonstration of Ka-band digitally-beamformed radar for ice topography mapping

    E-Print Network [OSTI]

    Sadowy, G; Heavey, B; Moller, D; Rignot, E; Zawadzki, M; Rengarajan, S

    2007-01-01

    Beamformed Radar for Ice Topography Mapping Gregory Sadowy,Glacier and Land Ice Surface Topography Interferometer) is aGLISTIN will collect ice topography measurements over a wide

  4. On the Interaction of Methyl Azide (CH3N3) Ices with Ionizing Radiation: Formation of Methanimine (CH2NH), Hydrogen Cyanide (HCN), and Hydrogen Isocyanide (HNC)

    E-Print Network [OSTI]

    Kaiser, Ralf I.

    On the Interaction of Methyl Azide (CH3N3) Ices with Ionizing Radiation: Formation of Methanimine in solar system analogue ices. Introduction Methyl azide (CH3N3) is an organic compound suggested to be present in Titan's atmosphere.1 To date, the Voyager Infrared Radiometer and Infrared Spectrometer (IRIS

  5. Energy Saving Melting and Revert Reduction Technology (Energy-SMARRT): Clean Steel Casting Production

    SciTech Connect (OSTI)

    Kuyucak, Selcuk; Li, Delin

    2013-12-31

    Inclusions in steel castings can cause rework, scrap, poor machining, and reduced casting performance, which can obviously result in excess energy consumption. Significant progress in understanding inclusion source, formation and control has been made. Inclusions can be defined as non-metallic materials such as refractory, sand, slag, or coatings, embedded in a metallic matrix. This research project has focused on the mold filling aspects to examine the effects of pouring methods and gating designs on the steel casting cleanliness through water modeling, computer modeling, and melting/casting experiments. Early in the research project, comprehensive studies of bottom-pouring water modeling and low-alloy steel casting experiments were completed. The extent of air entrainment in bottom-poured large castings was demonstrated by water modeling. Current gating systems are designed to prevent air aspiration. However, air entrainment is equally harmful and no prevention measures are in current practice. In this study, new basin designs included a basin dam, submerged nozzle, and nozzle extension. The entrained air and inclusions from the gating system were significantly reduced using the new basin method. Near the end of the project, there has been close collaboration with Wescast Industries Inc., a company manufacturing automotive exhaust components. Both computer modeling using Magma software and melting/casting experiments on thin wall turbo-housing stainless steel castings were completed in this short period of time. Six gating designs were created, including the current gating on the pattern, non-pressurized, partially pressurized, naturally pressurized, naturally pressurized without filter, and radial choke gating without filter, for Magma modeling. The melt filling velocity and temperature were determined from the modeling. Based on the simulation results, three gating designs were chosen for further melting and casting experiments on the same casting pattern using the lip pouring method. It was observed again that gating designs greatly influenced the melt filling velocity and the number of inclusion defects. The radial choked gating showed improvements in casting cleanliness and yield over the other gatings, even though no mold filters were used in the gating system.

  6. Computer simulation study of surface wave dynamics at the crystal--melt interface

    E-Print Network [OSTI]

    Jorge Benet; Luis G. MacDowell; Eduardo Sanz

    2014-10-01

    We study, by means of computer simulations, the crystal-melt interface of three different systems: hard-spheres, Lennard Jones and the TIP4P/2005 water model. In particular, we focus on the dynamics of surface waves. We observe that the processes involved in the relaxation of surface waves are characterized by distinct time scales: a slow one related to the continuous recrystallization and melting, that is governed by capillary forces; and a fast one which we suggest to be due to a combination of processes that quickly cause small perturbations to the shape of the interface (like e. g. Rayleigh waves, subdiffusion, or attachment/detachment of particles to/from the crystal). The relaxation of surface waves becomes dominated by the slow process as the wavelength increases. Moreover, we see that the slow relaxation is not influenced by the details of the microscopic dynamics. In a time scale characteristic for the diffusion of the liquid phase, the relaxation dynamics of the crystal-melt interface of water is around one order of magnitude slower than that of Lennard Jones or hard spheres, which we ascribe to the presence of orientational degrees of freedom in the water molecule. Finally, we estimate the rate of crystal growth from our analysis of the capillary wave dynamics and compare it with previous simulation studies and with experiments for the case of water.

  7. Assimilation of Ice Concentration in an IceOcean Model R. W. LINDSAY AND J. ZHANG

    E-Print Network [OSTI]

    Zhang, Jinlun

    of the actual fields. The simulated ice thickness can then be used to determine the major modes of variability of the ice thickness and the physical processes that are important in their formation. The simulations from concentration measured by satellites is subject to errors (Kwok 2002), particularly during the summer when

  8. ICED'09/148 INTERNATIONAL CONFERENCE ON ENGINEERING DESIGN, ICED'09

    E-Print Network [OSTI]

    Papalambros, Panos

    , marketing, and psychology. Quantitative models from these disciplines can be integrated into a design for teaching product design and for designing products taking into account market and policy environments alongICED'09/148 INTERNATIONAL CONFERENCE ON ENGINEERING DESIGN, ICED'09 24 - 27 AUGUST 2009, STANFORD

  9. Device and method for skull-melting depth measurement

    DOE Patents [OSTI]

    Lauf, R.J.; Heestand, R.L.

    1993-02-09

    A method of skull-melting comprises the steps of: (a) providing a vessel adapted for a skull-melting process, the vessel having an interior, an underside, and an orifice connecting the interior and the underside; (b) disposing a waveguide in the orifice so that the waveguide protrudes sufficiently into the interior to interact with the skull-melting process; (c) providing a signal energy transducer in signal communication with the waveguide; (d) introducing into the vessel a molten working material; (e) carrying out the skull-melting process so that a solidified skull of the working material is formed, the skull and the vessel having an interface therebetween, the skull becoming fused to the waveguide so the signal energy can be transmitted through the waveguide and the skull without interference from the interface; (f) activating the signal energy transducer so that a signal is propagated through the waveguide; and, (g) controlling at least one variable of the skull-melting process utilizing feedback information derived from the propagated signal energy.

  10. Heat transfer in ice hockey halls: measurements, energy analysis and analytical ice pad temperature profile

    E-Print Network [OSTI]

    Ferrantelli, Andrea

    2015-01-01

    We consider heat transfer processes in an ice hockey hall, during operating conditions, with a bottom-up approach based upon on-site measurements. Detailed temperature data of both the ice pad and the air above the ice rink are used for a heat balance calculation in the steady-state regime, which quantifies the impact of each single heat source. We solve the heat equation in the ice slab in transient regime, and obtain a general analytical formula for the temperature profile. This solution is then applied to the resurfacing process by using our measurements as (time-dependent) boundary conditions (b.c.), and compared to an analogous numerical computation with good agreement. Our analytical formula is given with implicit initial condition and b.c., therefore it can be used not only in ice halls, but in a large variety of engineering applications.

  11. Heat transfer in ice hockey halls: measurements, energy analysis and analytical ice pad temperature profile

    E-Print Network [OSTI]

    Andrea Ferrantelli; Klaus Viljanen

    2015-06-30

    We consider heat transfer processes in an ice hockey hall, during operating conditions, with a bottom-up approach based upon on-site measurements. Detailed temperature data of both the ice pad and the air above the ice rink are used for a heat balance calculation in the steady-state regime, which quantifies the impact of each single heat source. We solve the heat equation in the ice slab in transient regime, and obtain a general analytical formula for the temperature profile. This solution is then applied to the resurfacing process by using our measurements as (time-dependent) boundary conditions (b.c.), and compared to an analogous numerical computation with good agreement. Our analytical formula is given with implicit initial condition and b.c., therefore it can be used not only in ice halls, but in a large variety of engineering applications.

  12. Technical and economical considerations of new DRI melting process

    SciTech Connect (OSTI)

    Ito, Shuzo; Tokuda, Koji; Sammt, F.; Gray, R.

    1997-12-31

    The new DRI melting process can effectively and economically produce high quality molten iron. This process utilizes hot charging of DRI directly from a reduction furnace into a dedicated new melting furnace. The molten iron from this DRI premelter can be charged into a steelmaking furnace, such as an electric arc furnace (EAF), where the molten iron, together with other iron sources, can be processed to produce steel. Alternatively the molten iron can be pigged or granulated for off-site merchant sales. Comprehensive research and development of the new process has been conducted including operational process simulation, melting tests using FASTMET DRI, slag technology development, and refractory corrosion testing. This paper describes the process concept, its operational characteristics and further applications of the process.

  13. Melt processing of Bi--2212 superconductors using alumina

    DOE Patents [OSTI]

    Holesinger, Terry G. (Los Alamos, NM)

    1999-01-01

    Superconducting articles and a method of forming them, where the superconducting phase of an article is Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.y (Bi-2212). Alumina is combined with Bi-2212 powder or Bi-2212 precursor powder and, in order to form an intimate mixture, the mixture is melted and rapidly cooled to form a glassy solid. The glassy solid is comminuted and the resulting powder is combined with a carrier. An alternative to melting is to form the mixture of nanophase alumina and material having a particle size of less than about 10 microns. The powder, with the carrier, is melt processed to form a superconducting article.

  14. A study of the influence of isotopic substitution on the melting point and temperature of maximum density of water by means of path integral simulations of rigid models

    E-Print Network [OSTI]

    McBride, Carl; Noya, Eva G; Vega, Carlos; 10.1039/C2CP42393F

    2012-01-01

    The melting point of ice Ih, as well as the temperature of maximum density (TMD) in the liquid phase, has been computed using the path integral Monte Carlo method. Two new models are introduced; TIP4PQ_D2O and TIP4PQ_T2O which are specifically designed to study D2O and T2O respectively. We have also used these models to study the "competing quantum effects" proposal of Habershon, Markland and Manolopoulos; the TIP4PQ/2005, TIP4PQ/2005 (D2O) and TIP4PQ/2005 (T2O) models are able to study the isotopic substitution of hydrogen for deuterium or tritium whilst constraining the geometry, while the TIP4PQ_D2O and TIP4PQ_T2O models, where the O-H bond lengths are progressively shortened, permit the study of the influence of geometry (and thus dipole moment) on the isotopic effects. For TIP4PQ_D2O - TIP4PQ/2005 we found a melting point shift of 4.9 K (experimentally the value is 3.68K) and a TMD shift of 6K (experimentally 7.2K). For TIP4PQ_T2O - TIP4PQ/2005 we found a melting point shift of 5.2 K (experimentally the ...

  15. An AeroCom Assessment of Black Carbon in Arctic Snow and Sea Ice

    SciTech Connect (OSTI)

    Jiao, C.; Flanner, M. G.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Berntsen, T.; Bian, Huisheng; Carslaw, K. S.; Chin, Mian; De Luca, N.; Diehl, Thomas; Ghan, Steven J.; Iversen, T.; Kirkevag, A.; Koch, Dorothy; Liu, Xiaohong; Mann, G. W.; Penner, Joyce E.; Pitari, G.; Schulz, M.; Seland, O.; Skeie, R. B.; Steenrod, Stephen D.; Stier, P.; Takemura, T.; Tsigaridis, Kostas; van Noije, T.; Yun, Yuxing; Zhang, Kai

    2014-03-07

    Though many global aerosols models prognose surface deposition, only a few models have been used to directly simulate the radiative effect from black carbon (BC) deposition to snow and sea-ice. Here, we apply aerosol deposition fields from 25 models contributing to two phases of the Aerosol Comparisons between Observations and Models (AeroCom) project to simulate and evaluate within snow BC concentrations and radiative effect in the Arctic. We accomplish this by driving the offline land and sea-ice components of the Community Earth System Model with different deposition fields and meteorological conditions from 2004-2009, during which an extensive field campaign of BC measurements in Arctic snow occurred. We find that models generally underestimate BC concentrations in snow in northern Russia and Norway, while overestimating BC amounts elsewhere in the Arctic. Although simulated BC distributions in snow are poorly correlated with measurements, mean values are reasonable. The multi-model mean (range) bias in BC concentrations, sampled over the same grid cells, snow depths, and months of measurements, are -4.4 (-13.2 to +10.7) ng g?1 for an earlier Phase of AeroCom models (Phase I), and +4.1 (-13.0 to +21.4) ng g?1 for a more recent Phase of AeroCom models (Phase II), compared to the observational mean of 19.2 ng g?1. Factors determining model BC concentrations in Arctic snow include Arctic BC emissions, transport of extra-Arctic aerosols, precipitation, deposition efficiency of aerosols within the Arctic, and meltwater removal of particles in snow. Sensitivity studies show that the model–measurement evaluation is only weakly affected by meltwater scavenging efficiency because most measurements were conducted in non-melting snow. The Arctic (60-90?N) atmospheric residence time for BC in Phase II models ranges from 3.7 to 23.2 days, implying large inter-model variation in local BC deposition efficiency. Combined with the fact that most Arctic BC deposition originates from extra-Arctic emissions, these results suggest that aerosol removal processes are a leading source of variation in model performance. The multi-model mean (full range) of Arctic radiative effect from BC in snow is 0.15 (0.07-0.25) W m?2 and 0.18 (0.06-0.28) W m?2 in Phase I and Phase II models, respectively. After correcting for model biases relative to observed BC concentrations in different regions of the Arctic, we obtain a multi-model mean Arctic radiative effect of 0.17 W m?2 for the combined AeroCom ensembles. Finally, there is a high correlation between modeled BC concentrations sampled over the observational sites and the Arctic as a whole, indicating that the field campaign provided a reasonable sample of the Arctic.

  16. Fast Numerical Method for Growth and Retreat of Subsurface Ice on Mars Norbert Schorghofer

    E-Print Network [OSTI]

    Schörghofer, Norbert

    ice, retreat of pore ice, retreat of an ice sheet, and retreat of pore ice due to geothermal heating is the vertical spatial resolution and D the diffusion coefficient. The vertical grid spacing needs to be finer

  17. Aerosol source term in high pressure melt ejection

    SciTech Connect (OSTI)

    Brockmann, J.E.; Tarbell, W.W.

    1984-11-01

    Pressurized ejection of melt from a reactor pressure vessel has been identified as an important element of a severe reactor accident. Copious aerosol production is observed when thermitically generated melts pressurized with nitrogen or carbon dioxide to 1.3 to 17 MPa are ejected into an air atmosphere. Aerosol particle size distributions measured in the tests have modes of about 0.5, 5, and > 10 ..mu..m. Mechanisms leading to formation of these multimodal size distributions are suggested. This aerosol is a potentially important fission product source term that has not been considered in previous severe accident analyses.

  18. Depleted uranium dioxide melting in cold crucible melter and production of granules from the melt for use in casks for spent nuclear fuel and radioactive wastes

    SciTech Connect (OSTI)

    Gotovchikov, V.T.; Seredenko, V.A.; Shatalov, V.V.; Mironov, B.S.; Kaplenkov, V.N.; Seredenko, A.V.; Saranchin, V.K.; Shulgin, A.S. [All-Russian Research Institute of Chemical Technology (ARRICT), Moscow (Russian Federation); Haire, M.J.; Forsberg, C.W. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

    2007-07-01

    This paper describes the results of a joint research program between the Russian Research Institute of Chemical Technology and Oak Ridge National Laboratory in the United States to develop new radiation shielding materials for use in the construction of casks for spent nuclear fuel (SNF) and radioactive wastes. Research and development is underway to develop SNF storage, transport, and disposal casks using shielding made with two new depleted uranium dioxide (DUO{sub 2}) materials: a DUO{sub 2}-steel cermet, and, DUCRETE with DUAGG (DUO{sub 2} aggregate). Melting the DUO{sub 2} and allowing it to freeze will produce a near 100% theoretical density product and assures that the product produces no volatile materials upon subsequent heating. Induction cold-crucible melters (ICCM) are being developed for this specific application. An ICCM is, potentially, a high throughput low-cost process. Schematics of a pilot facility were developed for the production of molten DUO{sub 2} from DU{sub 3}O{sub 8} to produce granules <1 mm in diameter in a continuous mode of operation. Thermodynamic analysis was conducted for uranium-oxygen system in the temperature range from 300 to 4000 K in various gas mediums. Temperature limits of stability for various uranium oxides were determined. Experiments on melting DUO{sub 2} were carried out in a high frequency ICCM in a cold crucible with a 120 mm in diameter. The microstructure of molten DUO{sub 2} was studied and lattice parameters were determined. It was experimentally proved, and validated by X-ray analysis, that an opportunity exists to produce molten DUO{sub 2} from mixed oxides (primarily DU{sub 3}O{sub 8}) by reduction melting in ICCM. This will allow using DU{sub 3}O{sub 8} directly to make DUO{sub 2}-a separate unit operation to produce UO{sub 2} feed material is not needed. Experiments were conducted concerning the addition of alloying components, gadolinium et al. oxides, into the DUO{sub 2} melt while in the crucible. These additives improve neutron and gamma radiation shielding and operation properties of the final solids. Cermet samples of 50 wt % DUO{sub 2} were produced. (authors)

  19. Improving Process Heating System Performance: A Sourcebook for...

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

    in Process Heating Systems Save Energy Now in Your Process Heating Systems ITP Metal Casting: Advanced Melting Technologies: Energy Saving Concepts and Opportunities for the...

  20. Equations of state of ice VI and ice VII at high pressure and high temperature

    SciTech Connect (OSTI)

    Bezacier, Lucile; Hanfland, Michael; Journaux, Baptiste; Perrillat, Jean-Philippe; Cardon, Hervé; Daniel, Isabelle

    2014-09-14

    High-pressure H{sub 2}O polymorphs among which ice VI and ice VII are abundant in the interiors of large icy satellites and exo-planets. Knowledge of the elastic properties of these pure H{sub 2}O ices at high-temperature and high-pressure is thus crucial to decipher the internal structure of icy bodies. In this study we assess for the first time the pressure-volume-temperature (PVT) relations of both polycrystalline pure ice VI and ice VII at high pressures and temperatures from 1 to 9 GPa and 300 to 450 K, respectively, by using in situ synchrotron X-ray diffraction. The PVT data are adjusted to a second-order Birch-Murnaghan equation of state and give V{sub 0} = 14.17(2) cm{sup 3}?mol{sup ?1}, K{sub 0} = 14.05(23) GPa, and ?{sub 0} = 14.6(14) × 10{sup ?5} K{sup ?1} for ice VI and V{sub 0} = 12.49(1) cm{sup 3}?mol{sup ?1}, K{sub 0} = 20.15(16) GPa, and ?{sub 0} = 11.6(5) × 10{sup ?5} K{sup ?1} for ice VII.

  1. A reconciled estimate of ice-sheet mass balance

    E-Print Network [OSTI]

    2012-01-01

    Estimate of Ice-Sheet Mass Balance Andrew Shepherd, 1 * Erikand models of surface mass balance and glacial isostaticThis Ice Sheet Mass Balance Exercise (IMBIE) was facilitated

  2. Searching for Cosmic Accelerators via IceCube

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

    Searching for Cosmic Accelerators via IceCube Searching for Cosmic Accelerators via IceCube Berkeley Lab Researchers Part of an International Hunt November 21, 2013 Lynn Yarris,...

  3. Cirrus cloud formation and the role of heterogeneous ice nuclei

    E-Print Network [OSTI]

    Froyd, Karl D.

    2013-01-01

    Composition, size, and phase are key properties that define the ability of an aerosol particle to initiate ice in cirrus clouds. Properties of cirrus ice nuclei (IN) have not been well constrained due to a lack of systematic ...

  4. An update on modeling land-ice/ocean interactions in CESM

    SciTech Connect (OSTI)

    Asay-davis, Xylar

    2011-01-24

    This talk is an update on ongoing land-ice/ocean coupling work within the Community Earth System Model (CESM). The coupling method is designed to allow simulation of a fully dynamic ice/ocean interface, while requiring minimal modification to the existing ocean model (the Parallel Ocean Program, POP). The method makes use of an immersed boundary method (IBM) to represent the geometry of the ice-ocean interface without requiring that the computational grid be modified in time. We show many of the remaining development challenges that need to be addressed in order to perform global, century long climate runs with fully coupled ocean and ice sheet models. These challenges include moving to a new grid where the computational pole is no longer at the true south pole and several changes to the coupler (the software tool used to communicate between model components) to allow the boundary between land and ocean to vary in time. We discuss benefits for ice/ocean coupling that would be gained from longer-term ocean model development to allow for natural salt fluxes (which conserve both water and salt mass, rather than water volume).

  5. Laboratory investigations of irradiated acetonitrile-containing ices on an interstellar dust analog

    SciTech Connect (OSTI)

    Abdulgalil, Ali G. M.; Marchione, Demian; Rosu-Finsen, Alexander; Collings, Mark P.; McCoustra, Martin R. S.

    2012-07-15

    Reflection-absorption infrared spectroscopy is used to study the impact of low-energy electron irradiation of acetonitrile-containing ices, under conditions close to those in the dense star-forming regions in the interstellar medium. Both the incident electron energy and the surface coverage were varied. The experiments reveal that solid acetonitrile is desorbed from its ultrathin solid films with a cross section of the order of 10{sup -17} cm{sup 2}. Evidence is presented for a significantly larger desorption cross section for acetonitrile molecules at the water-ice interface, similar to that previously observed for the benzene-water system.

  6. Effects of exchange bias on magnetotransport in permalloy kagome artificial spin ice

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

    Le, B. L.; Rench, D. W.; Misra, R.; O’Brien, L.; Leighton, C.; Samarth, N.; Schiffer, P.

    2015-02-01

    We investigate the magnetotransport properties of connected kagome artificial spin ice networks composed of permalloy nanowires. Our data show clear evidence of magnetic switching among the wires, both in the longitudinal and transverse magnetoresistance. An unusual asymmetry with field sweep direction appears at temperatures below about 20 K that appears to be associated with exchange bias resulting from surface oxidation of permalloy, and which disappears in alumina-capped samples. These results demonstrate that exchange bias is a phenomenon that must be considered in understanding the physics of such artificial spin ice systems, and that opens up new possibilities for their control.

  7. Scalable, Efficient, and Accurate Community Ice Sheet Model (SEACISM) PRINCIPAL INVESTIGATOR: Katherine J. Evans

    E-Print Network [OSTI]

    is to develop a scalable, efficient, and accurate Community Ice Sheet Model (Glimmer-CISM). A state-of -the's leadership computing facility system. CISM has short-term requirements to provide accurate, quantitative to the climate model development effort with minimal structural modification. CISM has already been coupled

  8. Instruments and Methods Intermediate-depth ice coring of high-altitude and polar glaciers

    E-Print Network [OSTI]

    Howat, Ian M.

    environmental impact and not to contaminate the ice core. In some cases, the borehole fluid and fuel make up >50% of the total field operation cargo. Reducing borehole-fluid and fuel require- ments minimizes contamination and ETED system. A new cutter design, drilling with a lubricant/cutting fluid and a new anti

  9. Light-absorbing Particles in Snow and Ice: Measurement and Modeling of Climatic and Hydrological Impact

    SciTech Connect (OSTI)

    Qian, Yun; Yasunari, Teppei J.; Doherty, Sarah J.; Flanner, M. G.; Lau, William K.; Ming, J.; Wang, Hailong; Wang, Mo; Warren, Stephen G.; Zhang, Rudong

    2015-01-01

    Light absorbing particles (LAP, e.g., black carbon, brown carbon, and dust) influence water and energy budgets of the atmosphere and snowpack in multiple ways. In addition to their effects associated with atmospheric heating by absorption of solar radiation and interactions with clouds, LAP in snow on land and ice can reduce the surface reflectance (a.k.a., surface darkening), which is likely to accelerate the snow aging process and further reduces snow albedo and increases the speed of snowpack melt. LAP in snow and ice (LAPSI) has been identified as one of major forcings affecting climate change, e.g. in the fourth and fifth assessment reports of IPCC. However, the uncertainty level in quantifying this effect remains very high. In this review paper, we document various technical methods of measuring LAPSI and review the progress made in measuring the LAPSI in Arctic, Tibetan Plateau and other mid-latitude regions. We also report the progress in modeling the mass concentrations, albedo reduction, radiative forcing, andclimatic and hydrological impact of LAPSI at global and regional scales. Finally we identify some research needs for reducing the uncertainties in the impact of LAPSI on global and regional climate and the hydrological cycle.

  10. Covered Product Category: Water-Cooled Ice Machines

    Office of Energy Efficiency and Renewable Energy (EERE)

    The Federal Energy Management Program (FEMP) provides acquisition guidance and federal efficiency requirements for water-cooled ice machines.

  11. Evaluation of Cloud-Resolving Model Intercomparison Simulations Using TWP-ICE Observations: Precipitation and Cloud Structure

    SciTech Connect (OSTI)

    Varble, Adam C.; Fridlind, Ann; Zipser, Ed; Ackerman, Andrew; Chaboureau, Jean-Pierre; Fan, Jiwen; Hill, Adrian; McFarlane, Sally A.; Pinty, Jean-Pierre; Shipway, Ben

    2011-06-24

    The Tropical Warm Pool - International Cloud Experiment (TWP-ICE) provided high quality model forcing and observational datasets through which detailed model and observational intercomparisons could be performed. In this first of a two part study, precipitation and cloud structures within nine cloud-resolving model simulations are compared with scanning radar reflectivity and satellite infrared brightness temperature observations during an active monsoon period from 19 to 25 January 2006. Most simulations slightly overestimate volumetric convective rainfall. Overestimation of simulated convective area by 50% or more in several simulations is somewhat offset by underestimation of mean convective rain rates. Stratiform volumetric rainfall is underestimated by 13% to 53% despite overestimation of stratiform area by up to 65% because stratiform rain rates in every simulation are much lower than observed. Although simulations match the peaked convective radar reflectivity distribution at low levels, they do not reproduce the peaked distributions observed above the melting level. Simulated radar reflectivity aloft in convective regions is too high in most simulations. 29 In stratiform regions, there is a large spread in model results with none resembling 30 observed distributions. Above the melting level, observed radar reflectivity decreases 31 more gradually with height than simulated radar reflectivity. A few simulations produce 32 unrealistically uniform and cold 10.8-?m infrared brightness temperatures, but several 33 simulations produce distributions close to observed. Assumed ice particle size 34 distributions appear to play a larger role than ice water contents in producing incorrect 35 simulated radar reflectivity distributions aloft despite substantial differences in mean 36 graupel and snow water contents across models. 37

  12. On the scalability of the Albany/FELIX first-order Stokes approximation ice sheet solver for large-scale simulations of the Greenland and Antarctic ice sheets

    SciTech Connect (OSTI)

    Tezaur, Irina K. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Tuminaro, Raymond S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Perego, Mauro [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Salinger, Andrew G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Price, Stephen F. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-01-01

    We examine the scalability of the recently developed Albany/FELIX finite-element based code for the first-order Stokes momentum balance equations for ice flow. We focus our analysis on the performance of two possible preconditioners for the iterative solution of the sparse linear systems that arise from the discretization of the governing equations: (1) a preconditioner based on the incomplete LU (ILU) factorization, and (2) a recently-developed algebraic multigrid (AMG) preconditioner, constructed using the idea of semi-coarsening. A strong scalability study on a realistic, high resolution Greenland ice sheet problem reveals that, for a given number of processor cores, the AMG preconditioner results in faster linear solve times but the ILU preconditioner exhibits better scalability. A weak scalability study is performed on a realistic, moderate resolution Antarctic ice sheet problem, a substantial fraction of which contains floating ice shelves, making it fundamentally different from the Greenland ice sheet problem. Here, we show that as the problem size increases, the performance of the ILU preconditioner deteriorates whereas the AMG preconditioner maintains scalability. This is because the linear systems are extremely ill-conditioned in the presence of floating ice shelves, and the ill-conditioning has a greater negative effect on the ILU preconditioner than on the AMG preconditioner.

  13. A Mechanism for Extrusion Instabilities in Polymer Melts

    E-Print Network [OSTI]

    Georgiou, Georgios

    POLYMER ENGINEERINGAND SCIENCE, DECEMBER 1999, Vol. 39, No. 12 #12;A Mechanismfor ExtrusionA Mechanism for Extrusion Instabilities in Polymer Melts M.FWULLAS Faculty of Applied Physics Foundationfor Research and Technology-HeUas(Fo. R. T.H.) Znstitute of Electronic Structure and Laser,P.O. Box

  14. Ice Simulation Using GPGPU Shadi Alawneh and Dennis Peters

    E-Print Network [OSTI]

    Peters, Dennis

    is to increase the understanding of interactions between ice and steel structures such as ships and oil rigsIce Simulation Using GPGPU Shadi Alawneh and Dennis Peters Electrical and Computer Engineering.alawneh, dpeters}@mun.ca Abstract-- Simulation of the behaviour of a ship operating in pack ice

  15. Hyper-Real-Time Ice Simulation and Modeling Using GPGPU

    E-Print Network [OSTI]

    Peters, Dennis

    Hyper-Real-Time Ice Simulation and Modeling Using GPGPU By c Shadi Alawneh, B. Eng., M. Eng's, Newfoundland Title: Hyper-Real-Time Ice Simulation and Modeling Using GPGPU Author: Shadi Alawneh, B. Eng operating in pack ice is a computationally in- tensive process to which General Purpose Computing

  16. Introduction Microorganisms in sea ice function ecologically in the

    E-Print Network [OSTI]

    Stewart, Frank

    where pelagic and sea ice habitats are intrinsically coupled (Laws 1985, Garrison 1991, Eicken 1992, Knox 1994, Garrison & Mathot 1996, Arrigo et al. 1997, Brierley & Thomas 2002). For instance, sea ice algae - primarily diatoms and phototrophic flagellates (e.g. Garrison 1991) - are inocula for ice

  17. 4, 709732, 2007 Ice-shelf ocean

    E-Print Network [OSTI]

    Boyer, Edmond

    and out over the continental slope10 into deep water. Glacial melt water is concentrated in a 200 m thick in the water mass transformations that take place there. The source water is Warm Deep Water (WDW), derived from Circumpolar Deep Water, an old, salty and relatively warm wa- ter mass. Around Antarctica

  18. 29April2011JohnLearnedatIceCubeDedication1 IceCube Dedication Symposium, Madison, Wisconsin

    E-Print Network [OSTI]

    Learned, John

    29April2011JohnLearnedatIceCubeDedication1 IceCube Dedication Symposium, Madison, Wisconsin 29 of Neutrino Studies #12;"Talking to the neighbors" 29April2011JohnLearnedatIceCubeDedication2 "A modest://www.economist.com/PrinterFriendly.cfm?story_id=18526871 Not what this talk is about.... SETI with Neutrinos #12;29April2011JohnLearnedatIceCubeDedication3

  19. GeoMelt{sup R} ICV{sup TM} Treatment of Sellafield Pond Solids Waste - 13414

    SciTech Connect (OSTI)

    Witwer, Keith; Woosley, Steve; Campbell, Brett [Kurion, Inc., GeoMelt Division, 3015 Horn Rapids Road, Richland, Washington (United States)] [Kurion, Inc., GeoMelt Division, 3015 Horn Rapids Road, Richland, Washington (United States); Wong, Martin; Hill, Joanne [AMEC Inc., Birchwood Park, 601 Faraday Street, Birchwood, Warrington, WA3 6GN (United Kingdom)] [AMEC Inc., Birchwood Park, 601 Faraday Street, Birchwood, Warrington, WA3 6GN (United Kingdom)

    2013-07-01

    Kurion, Inc., in partnership with AMEC Ltd., is demonstrating its GeoMelt{sup R} In-Container Vitrification (ICV){sup TM} Technology to Sellafield Ltd. (SL). SL is evaluating the proposition of directly converting a container (skip/box/drum) of raw solid ILW into an immobilized waste form using thermal treatment, such that the resulting product is suitable for interim storage at Sellafield and subsequent disposal at a future Geological Disposal Facility. Potential SL feed streams include sludges, ion-exchange media, sand, plutonium contaminated material, concrete, uranium, fuel cladding, soils, metals, and decommissioning wastes. The solid wastes have significant proportions of metallic constituents in the form of containers, plant equipment, structural material and swarf arising from the nuclear operations at Sellafield. GeoMelt's proprietary ICV process was selected for demonstration, with the focus being high and reactive metal wastes arising from solid ILW material. A composite surrogate recipe was used to demonstrate the technology towards treating waste forms of diverse types and shapes, as well as those considered difficult to process; all the while requiring few (if any) pre-treatment activities. Key strategic objectives, along with their success criterion, were established by SL for this testing, namely: 1. Passivate and stabilize the raw waste simulant, as demonstrated by the entire quantity of material being vitrified, 2. Immobilize the radiological and chemo-toxic species, as demonstrated via indicative mass balance using elemental analyses from an array of samples, 3. Production of an inert and durable product as evidenced by transformation of reactive metals to their inert oxide forms and satisfactory leachability results using PCT testing. Two tests were performed using the GeoMelt Demonstration Unit located at AMEC's Birchwood Park Facilities in the UK. Post-melt examination of the first test indicated some of the waste simulant had not fully processed, due to insufficient processing time and melt temperature. A second test, incorporating operational experience from the first test, was performed and resulted in all of the 138 kg of feed material being treated. The waste simulant portion, at 41 kg, constituted 30 wt% of the total feed mass, with over 90% of this being made up of various reactive and non-reactive metals. The 95 liters of staged material was volume reduced to 41 liters, providing a 57% overall feed to product volume reduction in a fully passivated two-phase glass/metal product. The GeoMelt equipment operated as designed, vitrifying the entire batch of waste simulant. Post-melt analytical testing verified that 91-99+% of the radiological tracer metals were uniformly distributed within the glass/cast refractory/metal product, and the remaining fraction was captured in the offgas filtration systems. PCT testing of the glass and inner refractory liner showed leachability results that outperform the DOE regulatory limit of 2 g/m{sup 2} for the radiological species of interest (Sr, Ru, Cs, Eu, Re), and by more than an order of magnitude better for standard reference analytes (B, Na, Si). (authors)

  20. Decadal scale variations in ice flow along Whillans Ice Stream and its tributaries, West Antarctica

    E-Print Network [OSTI]

    Stearns, Leigh; Jezek, Kenneth C.; van der Veen, Cornelis J.

    2005-01-05

    We investigate velocity changes occurring along Whillans Ice Stream (WIS) by comparing velocities derived from repeat aerial photographs acquired in 1985–89 (average date of 1987) to interferometric satellite radar (InSAR) ...

  1. Decadal-scale variations in ice flow along Whillans Ice Stream and its tributaries, West Antarctica

    E-Print Network [OSTI]

    Stearns, Leigh; Jezek, K.A.; van der Veen, Cornelis J.

    2005-01-01

    We investigate velocity changes occurring along Whillans Ice Stream (WIS) by comparing velocities derived from repeat aerial photographs acquired in 1985–89 (average date of 1987) to interferometric satellite radar (InSAR) ...

  2. Prediction of lake ice in the Netherlands

    E-Print Network [OSTI]

    Haak, Hein

    by HARMONIE ·Flake driven by ECMWF ensembles ·Conclusions and Outlook #12;Lake workshop sept 2012 Motivation Operational Observations ECMWF model #12;Lake workshop sept 2012 h D Air Water Ice ·Surface energy ·Radiative fluxes (Qs, Ql, absorbed solar radiation) ·Turbulent fluxes (sensible and latent heat fluxes

  3. Ice-volcano interactions Eyjafjallajkull volcano, Iceland

    E-Print Network [OSTI]

    Berthier, Etienne

    Ice-volcano interactions in Eyjafjallajökull volcano, Iceland Eyjólfur Magnússon1, Magnús Tumi Sciences, University of Iceland, Reykjavík, Iceland 2. Institute of Earth Sciences, University of Iceland, Reykjavík, Iceland 3. Icelandic Coast Guard SPIRIT workshop 29&30 April 2010, Toulouse Picture by Eyjólfur

  4. Shear wave attenuation and dispersion in melt-bearing olivine polycrystals

    E-Print Network [OSTI]

    interpretation and seismological implications Ulrich H. Faul, John D. Fitz Gerald, and Ian Jackson Research: seismic wave attenuation, olivine, partial melting, grain boundary sliding, grain boundary structure and dispersion in melt-bearing olivine polycrystals: 2. Microstructural interpretation and seismological

  5. CATALYTIC LIQUEFACTION BY ZINC CHLORIDE MELTS AT PRE-PYROLYSIS TEMPERATURE

    E-Print Network [OSTI]

    Vermeulen, T.

    2012-01-01

    CHLORIDE MELTS AT PRE-PYROLYSIS TEMPERATURE T. Vermeulen, C.CHLORIDE MELTS AT PRE-PYROLYSIS TEMPERATURE T. Vermeulen, C.rather than by thermal pyrolysis which requires appreciably

  6. ITP Metal Casting: Advanced Melting Technologies: Energy Saving Concepts and Opportunities for the Metal Casting Industry

    Office of Energy Efficiency and Renewable Energy (EERE)

    The study examines current and emerging melting technologies and discusses their technical barriers to scale-up issues and research needed to advance these technologies, improving melting efficiency, lowering metal transfer heat loss, and reducing scrap.

  7. Porous compaction in transient creep regime and implications for melt, petroleum, and CO2 circulation

    E-Print Network [OSTI]

    Kaminski, Edouard

    Porous compaction in transient creep regime and implications for melt, petroleum, and CO2 in transient creep regime and implications for melt, petroleum, and CO2 circulation, J. Geophys. Res., 113, B

  8. A melting model for variably depleted and enriched lherzolite in the plagioclase and spinel stability fields

    E-Print Network [OSTI]

    Till, Christy B.

    Here we develop a lherzolite melting model and explore the effects of variations in mantle composition, pressure, temperature, and H[subscript 2]O content on melt composition. New experiments and a compilation of experimental ...

  9. Advanced Melting Technologies: Energy Saving Concepts and Opportunities for the Metal Casting Industry

    SciTech Connect (OSTI)

    None

    2005-11-01

    The study examines current and emerging melting technologies and discusses their technical barriers to scale-up issues and research needed to advance these technologies, improving melting efficiency, lowering metal transfer heat loss, and reducing scrap.

  10. UDC 552.161 MELTING OF ACID VOLCANITES IN CONTACT WITH A

    E-Print Network [OSTI]

    Podladchikov, Yuri

    of Sciences, Moscow, and Sakhalin Pedagogic Institute, Yuzhno-Sakhalinsk There is evidence of melting of acid

  11. Lattice model of linear telechelic polymer melts. I. Inclusion of chain semiflexibility in the lattice cluster theory

    E-Print Network [OSTI]

    Wen-Sheng Xu; Karl F. Freed

    2015-06-26

    The lattice cluster theory (LCT) for the thermodynamics of polymer systems has recently been reformulated to treat strongly interacting self-assembling polymers composed of fully flexible linear telechelic chains [J. Dudowicz and K. F. Freed, J. Chem. Phys. \\textbf{136}, 064902 (2012)]. Here, we further extend the LCT for linear telechelic polymer melts to include a description of chain semiflexibility, which is treated by introducing a bending energy penalty whenever a pair of consecutive bonds from a single chain lies along orthogonal directions. An analytical expression for the Helmholtz free energy is derived for the model of semiflexible linear telechelic polymer melts. The extension provides a theoretical tool for investigating the influence of chain stiffness on the thermodynamics of self-assembling telechelic polymers, and for further exploring the influence of self-assembly on glass formation in such systems.

  12. Modeling the Fracture of Ice Sheets on Parallel Computers

    SciTech Connect (OSTI)

    Waisman, Haim; Tuminaro, Ray

    2013-10-10

    The objective of this project was to investigate the complex fracture of ice and understand its role within larger ice sheet simulations and global climate change. This objective was achieved by developing novel physics based models for ice, novel numerical tools to enable the modeling of the physics and by collaboration with the ice community experts. At the present time, ice fracture is not explicitly considered within ice sheet models due in part to large computational costs associated with the accurate modeling of this complex phenomena. However, fracture not only plays an extremely important role in regional behavior but also influences ice dynamics over much larger zones in ways that are currently not well understood. To this end, our research findings through this project offers significant advancement to the field and closes a large gap of knowledge in understanding and modeling the fracture of ice sheets in the polar regions. Thus, we believe that our objective has been achieved and our research accomplishments are significant. This is corroborated through a set of published papers, posters and presentations at technical conferences in the field. In particular significant progress has been made in the mechanics of ice, fracture of ice sheets and ice shelves in polar regions and sophisticated numerical methods that enable the solution of the physics in an efficient way.

  13. Freezing, melting, nonwetting, and coexistence in (KCl)32 John P. Rose and FL Stephen Berry

    E-Print Network [OSTI]

    Berry, R. Stephen

    Freezing, melting, nonwetting, and coexistence in (KCl)32 John P. Rose and FL Stephen Berry that of homogeneousclusters. The melting and freezing, nonwetting, and the complexity of the potential surfaceof (KC1)33areCl clustersexhibit simpleisomerizationdynamics, large NaCl clusters exhibit freezing/melting behavior sim- ilar

  14. Melting in an Enclosure with Discrete Heating at a Constant Rate

    E-Print Network [OSTI]

    Zhang, Yuwen

    - Melting in an Enclosure with Discrete Heating at a Constant Rate Yuwen Zhang Zhongqi Chen Qijie · The melting of n-octadecane that is discretely heated at a constant rate from one side of an enclosure- Experimental Thermal and Fluid Science 1993; 6:196-201 rate heating mode of the melting process

  15. Microscopic Description of Entanglements in Polyethylene Networks and Melts: Strong, Weak, Pairwise, and Collective Attributes

    E-Print Network [OSTI]

    Stefanos D. Anogiannakis; Christos Tzoumanekas; Doros N. Theodorou

    2013-01-30

    We present atomistic molecular dynamics simulations of two Polyethylene systems where all entanglements are trapped: a perfect network, and a melt with grafted chain ends. We examine microscopically at what level topological constraints can be considered as a collective entanglement effect, as in tube model theories, or as certain pairwise uncrossability interactions, as in slip-link models. A pairwise parameter, which varies between these limiting cases, shows that, for the systems studied, the character of the entanglement environment is more pairwise than collective. We employ a novel methodology, which analyzes entanglement constraints into a complete set of pairwise interactions, similar to slip links. Entanglement confinement is assembled by a plethora of links, with a spectrum of confinement strengths, from strong to weak. The strength of interactions is quantified through a link `persistence', which is the fraction of time for which the links are active. By weighting links according to their strength, we show that confinement is imposed mainly by the strong ones, and that the weak, trapped, uncrossability interactions cannot contribute to the low frequency modulus of an elastomer, or the plateau modulus of a melt. A self-consistent scheme for mapping topological constraints to specific, strong binary links, according to a given entanglement density, is proposed and validated. Our results demonstrate that slip links can be viewed as the strongest pairwise interactions of a collective entanglement environment. The methodology developed provides a basis for bridging the gap between atomistic simulations and mesoscopic slip link models.

  16. Methods of vitrifying waste with low melting high lithia glass compositions

    DOE Patents [OSTI]

    Jantzen, Carol M. (Aiken, SC); Pickett, John B. (Aiken, SC); Cicero-Herman, Connie A. (Aiken, SC); Marra, James C. (Aiken, SC)

    2001-01-01

    The invention relates to methods of vitrifying waste and for lowering the melting point of glass forming systems by including lithia formers in the glass forming composition in significant amounts, typically from about 0.16 wt % to about 11 wt %, based on the total glass forming oxides. The lithia is typically included as a replacement for alkali oxide glass formers that would normally be present in a particular glass forming system. Replacement can occur on a mole percent or weight percent basis, and typically results in a composition wherein lithia forms about 10 wt % to about 100 wt % of the alkali oxide glass formers present in the composition. The present invention also relates to the high lithia glass compositions formed by these methods. The invention is useful for stabilization of numerous types of waste materials, including aqueous waste streams, sludge solids, mixtures of aqueous supernate and sludge solids, combinations of spent filter aids from waste water treatment and waste sludges, supernate alone, incinerator ash, incinerator offgas blowdown, or combinations thereof, geological mine tailings and sludges, asbestos, inorganic filter media, cement waste forms in need of remediation, spent or partially spent ion exchange resins or zeolites, contaminated soils, lead paint, etc. The decrease in melting point achieved by the present invention desirably prevents volatilization of hazardous or radioactive species during vitrification.

  17. Pressurized melt ejection into water pools

    SciTech Connect (OSTI)

    Tarbell, W.W.; Pilch, M. (Sandia National Labs., Albuquerque, NM (USA)); Ross, J.W.; Oliver, M.S.; Gilbert, D.W.; Nichols, R.T. (Ktech Corp., Albuquerque, NM (USA))

    1991-03-01

    Direct Containment Heating is important because it is one of the postulated methods for early containment failure. If the reactor pressure vessel (RPV) should fail at an instrument tube penetration in the lower head, the resulting aperture would allow the molten core material to be discharged at high velocity into the cavity. Scaled experiments have demonstrated that the gas discharged during blowdown of the pressure system can entrain core debris and carry it out of the cavity region. Although these experiments were performed with the cavity initially devoid of water, other tests with the cavity partially filled with water exhibited similar results. The objective of the work described here is twofold: (1) to study the jet ejection and debris dispersal behavior when water is in contact with the lower head of the RPV and completely fills the cavity; and, (2) to compare the results of an experiment where the cavity is partially filled with water. These tests are of interest not only because they consider the dispersal of water and debris from the cavity but they also consider the potential consequences of codispersing water with core debris into the containment. Because the core debris may impart sufficient energy to the containment atmosphere to raise the pressure to potentially threatening levels, it is important to identify possible mitigating mechanisms. Analytical efforts have suggested that the codispersed water may act as a finely distributed heat sink that would have the beneficial effect of absorbing debris energy. This has not been confirmed experimentally, although the work presented here does attempt to identify the potential for water preexisting in the cavity to be dispersed as small droplets. 17 refs., 41 figs., 12 tabs.

  18. Molecular origin of the difference in the HOH bend of the IR spectra between liquid water and ice

    SciTech Connect (OSTI)

    Imoto, Sho; Xantheas, Sotiris S.; Saito, Shinji

    2013-02-07

    The intensity of the HOH bend in the IR spectrum of ice is significantly smaller than the corresponding one in liquid water. This difference in the IR intensities of the HOH bend in the two systems is investigated using MD simulations with the flexible, polarizable, ab-initio based TTM3-F model for water, a potential that correctly reproduces the experimentally observed increase of the HOH bend in liquid water and ice from the water monomer value. We have identified two factors that are responsible for the difference in the intensity of the HOH bend in liquid water and ice: (i) the decrease of the intensity of the HOH bend in ice caused by the strong anti-correlation between the permanent dipole moment of a molecule and the induced dipole moment of a neighboring hydrogen bond acceptor molecule and (ii) the weakening of this anti-correlation by the disordered hydrogen bond network in liquid water. The presence of the anti-correlation in ice is further confirmed by ab initio electronic structure calculations of water pentamer clusters extracted from the trajectories of the MD simulations for ice and liquid water.

  19. Polymer crystal-melt interfaces and nucleation in polyethylene

    E-Print Network [OSTI]

    Scott T. Milner

    2010-09-22

    Kinetic barriers cause polymers to crystallize incompletely, into nanoscale lamellae interleaved with amorphous regions. As a result, crystalline polymers are full of crystal-melt interfaces, which dominate their physical properties. The longstanding theoretical challenge to understand these interfaces has new relevance, because of accumulating evidence that polymer crystals often nucleate via a metastable, partially ordered "rotator" phase. To test this idea requires a theory of the bulk and interfacial free energies of the critical nucleus. We present a new approach to the crystal-melt interface, which represents the amorphous region as a grafted brush of loops in a self-consistent pressure field. We combine this theory with estimates of bulk free energy differences, to calculate nucleation barriers and rates via rotator versus crystal nuclei for polyethylene. We find rotator-phase nucleation is indeed favored throughout the temperature range where nucleation is observed. Our methods can be extended to other polymers.

  20. Extensional viscosity measurements of polyethylene using a melt flow indexer 

    E-Print Network [OSTI]

    Moffatt, Scott Gordon

    1999-01-01

    . . . . . . . . 142 APPENDIX C: CONSTANT STRESS RHEOMETER TESTING PROCEDURE. . . . . . APPENDIX D: MELT FLOW INDEXER DATA . . . . . 147 APPENDIX E: CAPILLARY RHEOMETER DATA. . . . . . 184 APPENDIX F: OSCILLATORY RHEOMETER DATA . . . . . . . . 213 APPENDIX G...) [Padmanabhan and Macosko (1997)] . . . . . 14 5 Bagley Correction Factor for the Capillary Rheometer. 23 6 Flow Index Determination. . . . . . . 28 7 Definitions of Lengths Used in the Darby Method. 8 Carreau-Yasuda Fit of Complex Viscosity Data for Resin E...

  1. By simulating biogeochemical cycles, the Greenland ice sheet, and more--with reach to the lower thermosphere--this system gives the research community a flexible, state-of-the-

    E-Print Network [OSTI]

    climate variability and change. THE COMMUNITY EARTH SYSTEM MODEL A Framework for Collaborative Research in the CCSM4/CESM1 (version 1.0 of the Community Earth System Model) special collection of the Journal processes must be represented before a climate model becomes an Earth system model (ESM), but typically

  2. Removing a sheet from the surface of a melt using gas jets

    DOE Patents [OSTI]

    Kellerman, Peter L; Thronson, Gregory D; Sun, Dawei

    2014-04-01

    In one embodiment, a sheet production apparatus comprises a vessel configured to hold a melt of a material. A cooling plate is disposed proximate the melt and is configured to form a sheet of the material on the melt. A first gas jet is configured to direct a gas toward an edge of the vessel. A sheet of a material is translated horizontally on a surface of the melt and the sheet is removed from the melt. The first gas jet may be directed at the meniscus and may stabilize this meniscus or increase local pressure within the meniscus.

  3. Melt-spin processing of high {Tc} oxide superconductors

    SciTech Connect (OSTI)

    Folkerts, T.J.; Wu, Hengning; Yoo, S.I.; Merkle, B.D.; Arrasmith, S.R.; Dennis, K.W.; Kramer, M.J.; McCallum, R.W.

    1993-10-01

    Containerless techniques offer distinct advantages for the melt processing of oxide superconductors. The majority of these materials form liquids which are highly reactive with standard crucible materials such as Al{sub 2}O{sub 3} and Pt, resulting in non-negligible contamination. We have developed a containerless melt-spin processing technique where in 50--400 {mu}m particles of REBa{sub 2}Cu{sub 3}O{sub 7-x} high temperature oxide superconductors are melted in free fall through a vertical tube furnace and quenched onto a copper wheel. Previously this method has been successful in producing glasses of NdBa{sub 2}Cu{sub 3}O{sub 7-x} and GdBa{sub 2}Cu{sub 3}O{sub 7-x}. In this report we discuss the results for both stoichiometric and non-stoichiometric YBa{sub 2}Cu{sub 3}O{sub 7-x} (Y123). Thermal, microstructural, and superconducting characterization of both the as-quenched and the annealed materials will be presented.

  4. Many-body interactions and melting of colloidal crystals

    E-Print Network [OSTI]

    J. Dobnikar; Y. Chen; R. Rzehak; H. H. von Grünberg

    2008-01-25

    We study the melting behavior of charged colloidal crystals, using a simulation technique that combines a continuous mean-field Poisson-Boltzmann description for the microscopic electrolyte ions with a Brownian-dynamics simulation for the mesoscopic colloids. This technique ensures that many-body interactions between the colloids are fully taken into account, and thus allows us to investigate how many-body interactions affect the solid-liquid phase behavior of charged colloids. Using the Lindemann criterion, we determine the melting line in a phase-diagram spanned by the colloidal charge and the salt concentration. We compare our results to predictions based on the established description of colloidal suspensions in terms of pairwise additive Yukawa potentials, and find good agreement at high-salt, but not at low-salt concentration. Analyzing the effective pair-interaction between two colloids in a crystalline environment, we demonstrate that the difference in the melting behavior observed at low salt is due to many-body interactions.

  5. Design of an Automatic Landing System for the Meridian UAV using Fuzzy Logic

    E-Print Network [OSTI]

    Royer, David Andrew

    2010-04-22

    This document describes the design of an automatic landing system for the Meridian unmanned aerial vehicle (UAV) in development for glacial ice research. The Center for Remote Sensing of Ice Sheets (CReSIS), established by the National Science...

  6. Atom addition reactions in interstellar ice analogues

    E-Print Network [OSTI]

    Linnartz, Harold; Fedoseev, Gleb

    2015-01-01

    This review paper summarizes the state-of-the-art in laboratory based interstellar ice chemistry. The focus is on atom addition reactions, illustrating how water, carbon dioxide and methanol can form in the solid state at astronomically relevant temperatures, and also the formation of more complex species such as hydroxylamine, an important prebiotic molecule, and glycolaldehyde, the smallest sugar, is discussed. These reactions are particularly relevant during the dark ages of star and planet formation, i.e., when the role of UV light is restricted. A quantitative characterization of such processes is only possible through dedicated laboratory studies, i.e., under full control of a large set of parameters such as temperature, atom-flux, and ice morphology. The resulting numbers, physical and chemical constants, e.g., barrier heights, reaction rates and branching ratios, provide information on the molecular processes at work and are needed as input for astrochemical models, in order to bridge the timescales t...

  7. Should we geoengineer larger ice caps?

    E-Print Network [OSTI]

    Haqq-Misra, Jacob

    2015-01-01

    The climate of Earth is susceptible to catastrophes that could threaten the longevity of human civilization. Geoengineering to reduce incoming solar radiation has been suggested as a way to mediate the warming effects of contemporary climate change, but a geoengineering program for thousands of years could also be used to enlarge the size of the polar ice caps and create a permanently cooler climate. Such a large ice cap state would make Earth less susceptible to climate threats and could allow human civilization to survive further into the future than otherwise possible. Intentionally extending Earth's glacial coverage will require uninterrupted commitment to this program for millenia but would ultimately reach a cooler equilibrium state where geoengineering is no longer needed. Whether or not this program is ever attempted, this concept illustrates the need to identify preference among potential climate states to ensure the long-term success of civilization.

  8. Large Scale Ice Water Path and 3-D Ice Water Content

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Liu, Guosheng

    2008-01-15

    Cloud ice water concentration is one of the most important, yet poorly observed, cloud properties. Developing physical parameterizations used in general circulation models through single-column modeling is one of the key foci of the ARM program. In addition to the vertical profiles of temperature, water vapor and condensed water at the model grids, large-scale horizontal advective tendencies of these variables are also required as forcing terms in the single-column models. Observed horizontal advection of condensed water has not been available because the radar/lidar/radiometer observations at the ARM site are single-point measurement, therefore, do not provide horizontal distribution of condensed water. The intention of this product is to provide large-scale distribution of cloud ice water by merging available surface and satellite measurements. The satellite cloud ice water algorithm uses ARM ground-based measurements as baseline, produces datasets for 3-D cloud ice water distributions in a 10 deg x 10 deg area near ARM site. The approach of the study is to expand a (surface) point measurement to an (satellite) areal measurement. That is, this study takes the advantage of the high quality cloud measurements at the point of ARM site. We use the cloud characteristics derived from the point measurement to guide/constrain satellite retrieval, then use the satellite algorithm to derive the cloud ice water distributions within an area, i.e., 10 deg x 10 deg centered at ARM site.

  9. Large Scale Ice Water Path and 3-D Ice Water Content

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Liu, Guosheng

    Cloud ice water concentration is one of the most important, yet poorly observed, cloud properties. Developing physical parameterizations used in general circulation models through single-column modeling is one of the key foci of the ARM program. In addition to the vertical profiles of temperature, water vapor and condensed water at the model grids, large-scale horizontal advective tendencies of these variables are also required as forcing terms in the single-column models. Observed horizontal advection of condensed water has not been available because the radar/lidar/radiometer observations at the ARM site are single-point measurement, therefore, do not provide horizontal distribution of condensed water. The intention of this product is to provide large-scale distribution of cloud ice water by merging available surface and satellite measurements. The satellite cloud ice water algorithm uses ARM ground-based measurements as baseline, produces datasets for 3-D cloud ice water distributions in a 10 deg x 10 deg area near ARM site. The approach of the study is to expand a (surface) point measurement to an (satellite) areal measurement. That is, this study takes the advantage of the high quality cloud measurements at the point of ARM site. We use the cloud characteristics derived from the point measurement to guide/constrain satellite retrieval, then use the satellite algorithm to derive the cloud ice water distributions within an area, i.e., 10 deg x 10 deg centered at ARM site.

  10. Resonant vibrational energy transfer in ice Ih

    SciTech Connect (OSTI)

    Shi, L.; Li, F.; Skinner, J. L.

    2014-06-28

    Fascinating anisotropy decay experiments have recently been performed on H{sub 2}O ice Ih by Timmer and Bakker [R. L. A. Timmer, and H. J. Bakker, J. Phys. Chem. A 114, 4148 (2010)]. The very fast decay (on the order of 100 fs) is indicative of resonant energy transfer between OH stretches on different molecules. Isotope dilution experiments with deuterium show a dramatic dependence on the hydrogen mole fraction, which confirms the energy transfer picture. Timmer and Bakker have interpreted the experiments with a Förster incoherent hopping model, finding that energy transfer within the first solvation shell dominates the relaxation process. We have developed a microscopic theory of vibrational spectroscopy of water and ice, and herein we use this theory to calculate the anisotropy decay in ice as a function of hydrogen mole fraction. We obtain very good agreement with experiment. Interpretation of our results shows that four nearest-neighbor acceptors dominate the energy transfer, and that while the incoherent hopping picture is qualitatively correct, vibrational energy transport is partially coherent on the relevant timescale.

  11. Microscopic Description of Entanglements in Polyethylene Networks and Melts: Strong, Weak, Pairwise, and Collective Attributes

    E-Print Network [OSTI]

    Anogiannakis, Stefanos D; Theodorou, Doros N

    2012-01-01

    We present atomistic molecular dynamics simulations of two Polyethylene systems where all entanglements are trapped: a perfect network, and a melt with grafted chain ends. We examine microscopically at what level topological constraints can be considered as a collective entanglement effect, as in tube model theories, or as certain pairwise uncrossability interactions, as in slip-link models. A pairwise parameter, which varies between these limiting cases, shows that, for the systems studied, the character of the entanglement environment is more pairwise than collective. We employ a novel methodology, which analyzes entanglement constraints into a complete set of pairwise interactions, similar to slip links. Entanglement confinement is assembled by a plethora of links, with a spectrum of confinement strengths, from strong to weak. The strength of interactions is quantified through a link `persistence', which is the fraction of time for which the links are active. By weighting links according to their strength,...

  12. Multifractal analysis of stress time series during ultrathin lubricant film melting

    E-Print Network [OSTI]

    A. V. Khomenko; I. A. Lyashenko; V. N. Borisyuk

    2010-07-20

    Melting of an ultrathin lubricant film confined between two atomically flat surfaces is we studied using the rheological model for viscoelastic matter approximation. Phase diagram with domains, corresponding to sliding, dry, and two types of $stick-slip$ friction regimes has been built taking into account additive noises of stress, strain, and temperature of the lubricant. The stress time series have been obtained for all regimes of friction using the Stratonovich interpretation. It has been shown that self-similar regime of lubricant melting is observed when intensity of temperature noise is much larger than intensities of strain and stress noises. This regime is defined by homogenous distribution, at which characteristic stress scale is absent. We study stress time series obtained for all friction regimes using multifractal detrended fluctuation analysis. It has been shown that multifractality of these series is caused by different correlations that are present in the system and also by a power-law distribution. Since the power-law distribution is related to small stresses, this case corresponds to self-similar solid-like lubricant.

  13. Structural aspects of glass-formation in Ni-Nb melts

    SciTech Connect (OSTI)

    Holland-Moritz, D.; Yang, F.; Gegner, J.; Meyer, A. [Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln (Germany); Hansen, T. [Institut Laue-Langevin (ILL), 38042 Grenoble (France); Ruiz-Martín, M. D. [Grup de Caracterització de Materials, Departament de Física i Enginyeria Nuclear, Universitat Politècnica de Catalunya, Barcelona (Spain); Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln (Germany)

    2014-05-28

    We report on investigations of the static structure factors of glass-forming Ni{sub 59.5}Nb{sub 40.5} alloy melts by combination of the containerless processing technique of electrostatic levitation with neutron diffraction. By application of the isotopic substitution method, the full set of partial structure factors was determined. The short-range order in liquid Ni{sub 59.5}Nb{sub 40.5} is characterized by a large nearest neighbor coordination number of Z{sub NN}?=?14.3 and a chemical short-range order with an affinity for the formation of heterogeneous Nb-Ni nearest neighbors. The structure factors observed here in the liquid state closely resemble those reported for amorphous Nb-Ni solids. The comparison with earlier results on the short-range structure in Zr-based glass-forming melts suggests that a large local density of packing, chemical order, and structural frustration are, amongst others, common structural properties of these metallic glass-forming systems, which favor glass-formation.

  14. A radio air shower surface detector as an extension for IceCube and IceTop

    E-Print Network [OSTI]

    J. Auffenberg; T. Gaisser; K. Helbing; T. Huege; T. Karg; A. Karle

    2007-08-24

    The IceCube neutrino detector is built into the Antarctic ice sheet at the South Pole to measure high energy neutrinos. For this, 4800 photomultiplier tubes (PMTs) are being deployed at depths between 1450 and 2450 meters into the ice to measure neutrino induced charged particles like muons. IceTop is a surface air shower detector consisting of 160 Cherenkov ice tanks located on top of IceCube. To extend IceTop, a radio air shower detector could be built to significantly increase the sensitivity at higher shower energies and for inclined showers. As air showers induced by cosmic rays are a major part of the muonic background in IceCube, IceTop is not only an air shower detector, but also a veto to reduce the background in IceCube. Air showers are detectable by radio signals with a radio surface detector. The major emission process is the coherent synchrotron radiation emitted by e+ e- shower particles in the Earths magnetic field (geosynchrotron effect). Simulations of the expected radio signals of air showers are shown. The sensitivity and the energy threshold of different antenna field configurations are estimated.

  15. IceVeto: Extended PeV neutrino astronomy in the Southern Hemisphere with IceCube

    SciTech Connect (OSTI)

    Auffenberg, Jan; Collaboration: IceCube Collaboration

    2014-11-18

    IceCube, the world's largest high-energy neutrino observatory, built at the South Pole, recently reported evidence of an astrophysical neutrino flux extending to PeV energies in the Southern Hemisphere. This observation raises the question of how the sensitivity in this energy range could be further increased. In the down-going sector, in IceCube's case the Southern Hemisphere, backgrounds from atmospheric muons and neutrinos pose a challenge to the identification of an astrophysical neutrino flux. The IceCube analysis, that led to the evidence for astrophysical neutrinos, is based on an in-ice veto strategy for background rejection. One possibility available to IceCube is the concept of an extended surface detector, IceVeto, which could allow the rejection of a large fraction of atmospheric backgrounds, primarily for muons from cosmic ray (CR) air showers as well as from neutrinos in the same air showers. Building on the experience of IceTop/IceCube, possibly the most cost-effective and sensitive way to build IceVeto is as an extension of the IceTop detector, with simple photomultiplier based detector modules for CR air shower detection. Initial simulations and estimates indicate that such a veto detector will significantly increase the sensitivity to an astrophysical flux of ?{sub ?} induced muon tracks in the Southern Hemisphere compared to current analyses. Here we present the motivation and capabilities based on initial simulations. Conceptual ideas for a simplified surface array will be discussed briefly.

  16. Carbon dioxide in silica-undersaturated melt Part I: The effect of mixed alkalis (K and Na) on CO2 solubility and speciation.

    E-Print Network [OSTI]

    Boyer, Edmond

    . These low-silica melts can dissolve a large quantity of CO2 and are rich in alkalis. However, the way CO2 experimental results on the CO2 solubility and speciation in synthetic nephelinite in the NKCMAS system, equilibrated at high-pressure (50-300 MPa), high-temperature (1250C) with an excess C-O-H fluid phase

  17. ORIGINAL PAPER Sedimentary pellets as an ice-cover proxy in a High Arctic

    E-Print Network [OSTI]

    Vincent, Warwick F.

    ORIGINAL PAPER Sedimentary pellets as an ice-cover proxy in a High Arctic ice-covered lake Jessica-cover extent and dynamics on this perennially ice-covered, High Arctic lake. These pellets are interpreted growth. The pellets remain frozen in the ice until a summer or series of summers with reduced ice cover

  18. Glacial conditions that contribute to the regeneration of Fountain Glacier proglacial icing, Bylot Island, Canada

    E-Print Network [OSTI]

    Moorman, Brian

    Glacial conditions that contribute to the regeneration of Fountain Glacier proglacial icing, Bylot icings are one of the most common forms of extrusive ice found in the Canadian Arctic. However, the icing. Its regeneration depends on the availability of subglacial water and on the balance between ice

  19. In this issue we say good-bye to Centre Manager, Tamsin Falconer after eight years with the ARC, profile Nancy Bertler's Roosevelt Island ice coring programme and highlight the research projects of some of our graduate students. We also

    E-Print Network [OSTI]

    Zealand, our new Intermediate Depth Ice Core Drilling system, modelled after the Danish Hans Tausen Drill Antarctic Ice Sheet collapse. In preparation for the drilling seasons, Antarctica New Zealand and US Polar 1,000 snow samples, and winterised over 50,000 lbs of equipment and fuel for next year's drilling

  20. Meltwater effects on flow of Greenland's ice sheet less severe...

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

    Side effects of increasing meltwater less severe than feared Meltwater effects on flow of Greenland's ice sheet less severe for sea level rise than earlier feared, scientists...

  1. Sandia Energy - NASA Award for Marginal Ice Zone Observations...

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

    NASA Award for Marginal Ice Zone Observations and Process Experiment (MIZOPEX) Home Climate Office of Science News News & Events Research & Capabilities Monitoring Analysis...

  2. THE STICKINESS OF MICROMETER-SIZED WATER-ICE PARTICLES

    SciTech Connect (OSTI)

    Gundlach, B.; Blum, J.

    2015-01-01

    Water ice is one of the most abundant materials in dense molecular clouds and in the outer reaches of protoplanetary disks. In contrast to other materials (e.g., silicates), water ice is assumed to be stickier due to its higher specific surface energy, leading to faster or more efficient growth in mutual collisions. However, experiments investigating the stickiness of water ice have been scarce, particularly in the astrophysically relevant micrometer-sized region and at low temperatures. In this work, we present an experimental setup to grow aggregates composed of ?m-sized water-ice particles, which we used to measure the sticking and erosion thresholds of the ice particles at different temperatures between 114 K and 260 K. We show with our experiments that for low temperatures (below ?210 K), ?m-sized water-ice particles stick below a threshold velocity of 9.6 m s{sup –1}, which is approximately 10 times higher than the sticking threshold of ?m-sized silica particles. Furthermore, erosion of the grown ice aggregates is observed for velocities above 15.3 m s{sup –1}. A comparison of the experimentally derived sticking threshold with model predictions is performed to determine important material properties of water ice, i.e., the specific surface energy and the viscous relaxation time. Our experimental results indicate that the presence of water ice in the outer reaches of protoplanetary disks can enhance the growth of planetesimals by direct sticking of particles.

  3. IceCube: An Instrument for Neutrino Astronomy

    E-Print Network [OSTI]

    Halzen, F.

    2010-01-01

    detectors: searching for radio waves or for acoustic pulsespredictions 93 . In cold ice, radio-wave attenuation lengthperfect reflector for radio waves. With this reflection,

  4. Covered Product Category: Air-Cooled Ice Machines

    Broader source: Energy.gov [DOE]

    The Federal Energy Management Program (FEMP) provides acquisition guidance for air-cooled ice machines, which are covered by the ENERGY STAR program.

  5. Acceleration of Greenland ice mass loss in spring 2004

    E-Print Network [OSTI]

    Velicogna, I; Velicogna, I; Wahr, J

    2006-01-01

    10.1029/ 2005GL025550 (2006). Peltier, W. R. Global glacial2004). Tushingham, A. M. & Peltier, W. R. ICE-3G: A new

  6. IceCube: A Cubic Kilometer Radiation Detector

    E-Print Network [OSTI]

    Klein, S.; IceCube Collaboration

    2008-01-01

    Cubic Kilometer Radiation Detector The IceCube CollaborationA Cubic Kilometer Radiation Detector Spencer R. Klein, forlarge detector is to search for optical Cherenkov radiation

  7. ARM - Field Campaign - SGP Ice Nuclei Characterization Experiment

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

    and their impact on clouds and climate therefore remain relatively unconstrained. Soils of all types and plant surfaces are sources for ice nucleating particles that are...

  8. A METHOD FOR AIRCRAFT ICING DIAGNOSIS IN PRECIPITATION

    E-Print Network [OSTI]

    Fabry, Frederic

    A METHOD FOR AIRCRAFT ICING DIAGNOSIS IN PRECIPITATION François A. Turcotte Department precipitation event and its microphysics was simulated using a high resolution three-dimensional kinematic cloud

  9. Radiokrypton Dating Identifies Ancient Antarctic Ice | U.S. DOE...

    Office of Science (SC) Website

    Radiokrypton Dating Identifies Ancient Antarctic Ice Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Funding Opportunities Nuclear Science...

  10. Energy Saving Melting and Revert Reduction Technology: Innovative Semi-Solid Metal (SSM) Processing

    SciTech Connect (OSTI)

    Diran Apelian

    2012-08-15

    Semi-solid metal (SSM) processing has emerged as an attractive method for near-net-shape manufacturing due to the distinct advantages it holds over conventional near-net-shape forming technologies. These advantages include lower cycle time, increased die life, reduced porosity, reduced solidification shrinkage, improved mechanical properties, etc. SSM processing techniques can not only produce the complex dimensional details (e.g. thin-walled sections) associated with conventional high-pressure die castings, but also can produce high integrity castings currently attainable only with squeeze and low-pressure permanent mold casting processes. There are two primary semi-solid processing routes, (a) thixocasting and (b) rheocasting. In the thixocasting route, one starts from a non-dendritic solid precursor material that is specially prepared by a primary aluminum manufacturer, using continuous casting methods. Upon reheating this material into the mushy (a.k.a. "two-phase") zone, a thixotropic slurry is formed, which becomes the feed for the casting operation. In the rheocasting route (a.k.a. "slurry-on-demand" or "SoD"), one starts from the liquid state, and the thixotropic slurry is formed directly from the melt via careful thermal management of the system; the slurry is subsequently fed into the die cavity. Of these two routes, rheocasting is favored in that there is no premium added to the billet cost, and the scrap recycling issues are alleviated. The CRP (Trade Marked) is a process where the molten metal flows through a reactor prior to casting. The role of the reactor is to ensure that copious nucleation takes place and that the nuclei are well distributed throughout the system prior to entering the casting cavity. The CRP (Trade Marked) has been successfully applied in hyper-eutectic Al-Si alloys (i.e., 390 alloy) where two liquids of equal or different compositions and temperatures are mixed in the reactor and creating a SSM slurry. The process has been mostly used for hypo-eutectic Al-Si alloys (i.e., 356, 357, etc.) where a single melt passes through the reactor. In addition, the CRP (Trade Marked) was designed to be flexible for thixocasting or rheocasting applications as well as batch or continuous casting. Variable heat extraction rates can be obtained by controlling either the superheat of the melt, the temperature of the channel system, or the temperature of the reactor. This program had four main objectives all of which were focused on a mechanistic understanding of the process in order to be able to scale it up, to develop it into a robust process,and for SSM processing to be commercially used.

  11. Method to decrease loss of aluminum and magnesium melts

    DOE Patents [OSTI]

    Hryn, John N. (Naperville, IL); Pellin, Michael J. (Naperville, IL); Calaway, Jr., Wallis F. (Woodridge, IL); Moore, Jerry F. (Naperville, IL); Krumdick, Gregory K. (Crete, IL)

    2002-01-01

    A method to minimize oxidation of metal during melting processes is provided, the method comprising placing solid phase metal into a furnace environ-ment, transforming the solid-phase metal into molten metal phase having a molten metal surface, and creating a barrier between the surface and the environment. Also provided is a method for isolating the surface of molten metal from its environment, the method comprising confining the molten metal to a controlled atmos-phere, and imposing a floating substrate between the surface and the atmosphere.

  12. An Extendible Reconfigurable Robot Based on Hot Melt Adhesives

    E-Print Network [OSTI]

    Brodbeck, Luzius; Iida, Fumiya

    2015-01-01

    liquid HMA from the nozzle of the HMA-supplier. The thermo-connector is covered by a flat copper connection surface (25mm× 30mm) that is heated and cooled to form or break bonds with the HMA in contact with the connection surface. A Peltier element (Cente... the experimental setup and robot platform, this section explains the experimental results on the me- chanical bounds of self-reconfiguration with our robotic (a) melting cavity HMA stick nozzle servo motor (b) connection surface peltier element power resisitor (c...

  13. Core melt/coolant interactions: modelling. [PWR; BWR

    SciTech Connect (OSTI)

    Berman, M.; McGlaun, J.M.; Corradini, M.L.

    1983-01-01

    If there is not adequate cooling water in the core of a light-water reactor (LWR), the fission product decay heat would eventually cause the reactor fuel and cladding to melt. This could lead to slumping of the molten core materials into the lower plenum of the reactor vessel, possibly followed by failure of the vessel wall and pouring of the molten materials into the reactor cavity. When the molten core materials enter either region, there is a strong possibility of molten core contacting water. This paper focuses on analysis of recent FITS experiments, mechanistic and probabilistic model development, and the application of these models to reactor considerations.

  14. Hydrostatic extrusion of Cu-Ag melt spun ribbon

    DOE Patents [OSTI]

    Hill, Mary Ann (Los Alamos, NM); Bingert, John F. (Jemez Springs, NM); Bingert, Sherri A. (Jemez Springs, NM); Thoma, Dan J. (Los Alamos, NM)

    1998-01-01

    The present invention provides a method of producing high-strength and high-conductance copper and silver materials comprising the steps of combining a predetermined ratio of the copper with the silver to produce a composite material, and melt spinning the composite material to produce a ribbon of copper and silver. The ribbon of copper and silver is heated in a hydrogen atmosphere, and thereafter die pressed into a slug. The slug then is placed into a high-purity copper vessel and the vessel is sealed with an electron beam. The vessel and slug then are extruded into wire form using a cold hydrostatic extrusion process.

  15. Hydrostatic extrusion of Cu-Ag melt spun ribbon

    DOE Patents [OSTI]

    Hill, M.A.; Bingert, J.F.; Bingert, S.A.; Thoma, D.J.

    1998-09-08

    The present invention provides a method of producing high-strength and high-conductance copper and silver materials comprising the steps of combining a predetermined ratio of the copper with the silver to produce a composite material, and melt spinning the composite material to produce a ribbon of copper and silver. The ribbon of copper and silver is heated in a hydrogen atmosphere, and thereafter die pressed into a slug. The slug then is placed into a high-purity copper vessel and the vessel is sealed with an electron beam. The vessel and slug then are extruded into wire form using a cold hydrostatic extrusion process. 5 figs.

  16. Low-melting point inorganic nitrate salt heat transfer fluid

    DOE Patents [OSTI]

    Bradshaw, Robert W. (Livermore, CA); Brosseau, Douglas A. (Albuquerque, NM)

    2009-09-15

    A low-melting point, heat transfer fluid made of a mixture of four inorganic nitrate salts: 9-18 wt % NaNO.sub.3, 40-52 wt % KNO.sub.3, 13-21 wt % LiNO.sub.3, and 20-27 wt % Ca(NO.sub.3).sub.2. These compositions can have liquidus temperatures less than 100 C; thermal stability limits greater than 500 C; and viscosity in the range of 5-6 cP at 300 C; and 2-3 cP at 400 C.

  17. Sandia Energy - Molten Salt Test Loop Melted Salt

    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 WebQuantityBonneville Power AdministrationRobust, High-Throughput Analysis ofSampleLignin-Feasting MicrobeMesaAnalysisSuccessMelted

  18. Effective stress profiles and seepage flows beneath glaciers and ice sheets

    E-Print Network [OSTI]

    Rempel, Alan W.

    stress for ice infiltration Qb Heat flux into glacier base Qf Heat produced by dissipation Qg Geothermal Vertical coordinate Exponent in permeability relation #12; Exponent in ice-saturation relation il Ice

  19. Analytical determination of performance degradation on a helicopter main rotor due to ice accretion 

    E-Print Network [OSTI]

    Camba, Javier

    1986-01-01

    artificial icing tests Canada's National Research Council (NRC) Icing Tunnel and simulated ice tests the OSU Transonic Airfoil Facility using a irfo'1 1 s inbicitave of current rotorcraft technol ogy. The final correlations are: Lift Increment Prediction...

  20. Incorporation of particulates into accreted ice above subglacial Vostok lake, Antarctica 

    E-Print Network [OSTI]

    Siegert, M. J.; Royston-Bishop, G.; Priscu, J. C.; Tranter, M.; Christner, B.; Lee, V.

    2005-01-01

    The nature of microscopic particulates in meteoric and accreted ice from the Vostok (Antarctica) ice core is assessed in conjunction with existing ice-core data to investigate the mechanism by which particulates are ...

  1. The re-evaluation of the AVR melt-wire experiment with specific focus on different modeling strategies and simplifications

    SciTech Connect (OSTI)

    R. Sonat Sen; Carel F. Viljoen

    2012-10-01

    The AVR is a pebble-bed type reactor that operated in Germany for 21 years and was closed down in December 1988. The AVR melt-wire experiments, where graphite spheres with melt wires of different melting temperatures were introduced into the core, indicate that measured pebble temperatures significantly exceeded temperatures calculated with the analysis codes available at the time. The reason for these discrepancies are often attributed to the special design features of the AVR, in particular the control rod “noses” protruding into the core, and to inherent features of the pebble bed reactor. In a previous study different possible bypass flows were investigated. This study investigates different modeling strategies and assumptions for the solution of the core neutronics. Due to the complexities specific to the AVR there is not currently a code system that can take into account the noses while simultaneously solving the burnup and diffusion equations in three dimensions. A number of modeling simplifications were therefore made in the historic analysis of the AVR. The aim of this study is to quantify the effects these different simplifications have on the results. This includes the effects of modeling the core neutronics, burn-up and thermo-hydraulics in both two and three dimensions, as well as other simplifications of the geometry. The comparison of the most realistic case to the one comparable to historic calculations show that the difference in temperature predicted with these two models can be as high as 300 degrees C. The gas temperature distribution at the top of the core, where the maximum temperatures occur, is in fair agreement with the melt-wire experiment data even though few simplifications are introduced to the models and the power history has not been simulated. The results also serve as input to the final modeling strategy to repeat the modeling of the operational history of the AVR, which is planned for the future.

  2. Distribution of CO2 ice on the large moons of Uranus and evidence for compositional stratification of their near-surfaces

    E-Print Network [OSTI]

    Cartwright, Richard J; Rivkin, Andy S; Trilling, David E; Pinilla-Alonso, Noemi

    2015-01-01

    The surfaces of the large Uranian satellites are characterized by a mixture of H2O ice and a dark, potentially carbon-rich, constituent, along with CO2 ice. At the mean heliocentric distance of the Uranian system, native CO2 ice should be removed on timescales shorter than the age of the Solar System. Consequently, the detected CO2 ice might be actively produced. Analogous to irradiation of icy moons in the Jupiter and Saturn systems, we hypothesize that charged particles caught in Uranus' magnetic field bombard the surfaces of the Uranian satellites, driving a radiolytic CO2 production cycle. To test this hypothesis, we investigated the distribution of CO2 ice by analyzing near-infrared (NIR) spectra of these moons, gathered using the SpeX spectrograph at NASA's Infrared Telescope Facility (IRTF) (2000 - 2013). Additionally, we made spectrophotometric measurements using images gathered by the Infrared Array Camera (IRAC) onboard the Spitzer Space Telescope (2003 - 2005). We find that the detected CO2 ice is ...

  3. H2 ICE Combustion | Argonne National Laboratory

    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 WebQuantityBonneville Power Administration would likeUniverse (Journalvivo Low-Dose Lowï‚— WeUpdate JonGuided 8/12/15GuyH2 ICE Combustion

  4. Ice in Arctic Mixed-phase Stratocumulus

    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 WebQuantityBonneville Power Administration would likeUniverse (JournalvivoHighHussein KhalilResearch88 Sign In AboutWorkshop:Ice Nuclei

  5. Southern Great Plains Ice Nuclei Characterization Experiment

    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 Home RoomPreservation ofAlbuquerque|Sensitive Species3performedValleySouthern Great Plains Ice Nuclei

  6. Melt state behaviour of PEEK and processing window interpretation for fast compression moulding process

    SciTech Connect (OSTI)

    Bessard, Emeline; De Almeida, Olivier; Bernhart, Gerard [Universite de Toulouse, INSA, UPS, Mines Albi, ISAE, ICA (Institut Clement Ader), Campus Jarlard, F-81013 Albi cedex 09 (France); Ecole des Mines Albi, Campus Jarlard, F-81013 Albi (France)

    2011-01-17

    Fast mould heating is nowadays possible by using induction technology for example with the Cage System registered developed by RocTool. It allows heating and cooling kinetics of about 100 deg. C per minute and new perspectives are thus possible to optimize the compression moulding process of long fibre reinforced thermoplastic composites. Indeed, a high forming temperature may favour polymer creep and so on composite consolidation. Nevertheless, the processing time of PEEK composite above melt temperature must be reduced to a few minutes due to the fast thermal degradation of the matrix. On the other hand, high cooling rates may have negative effect on matrix crystallinity. The proposed procedure consist in performing a few minutes isotherm around 300 deg. C during the fast cooling. It would favour a high degree of crystallinity of PEEK without extending the cycle time.

  7. Electrical charging during the sharkskin instability of a metallocene melt

    E-Print Network [OSTI]

    S. Tonon; A. Lavernhe-Gerbier; F. Flores; A. Allal; C. Guerret-Piécourt

    2007-07-18

    Flow instabilities are widely studied because of their economical and theoretical interest, however few results have been published about the polymer electrification during the extrusion. Nevertheless the generation of the electrical charges is characteristic of the interaction between the polymer melt and the die walls. In our study, the capillary extrusion of a metallocene polyethylene (mPE) through a tungsten carbide die is characterized through accurate electrical measurements thanks a Faraday pail. No significant charges are observed since the extrudate surface remains smooth. However, as soon as the sharkskin distortion appears, measurable charges are collected (around 5 10-8 C/m2). Higher level of charges are measured during the spurt or the gross-melt fracture (g.m.f) defects. This work is focused on the electrical charging during the sharkskin instability. The variation of the electrical charges versus the apparent wall shear stress is investigated for different die geometries. This curve exhibits a linear increase, followed by a sudden growth just before the onset of the spurt instability. This abrupt charging corresponds also to the end of the sharkskin instability. It is also well-known that wall slip appears just at the same time, with smaller velocity values than during spurt flow. Our results indicate that electrification could be a signature of the wall slip. We show also that the electrification curves can be shifted according to the time-temperature superposition principle, leading to the conclusion that molecular features of the polymer are also involved in this process.

  8. Microwires fabricated by glass-coated melt spinning

    SciTech Connect (OSTI)

    Zhao, Y. Y.; Li, H.; Hao, H. Y.; Li, M.; Zhang, Y. [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083 (China)] [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083 (China); Liaw, P. K. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996-2200 (United States)] [Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996-2200 (United States)

    2013-07-15

    The glass-coated melt spinning method offers a route for the manufacture of metal filaments with a few micrometers in diameter in a single operation directly from the melt. Cobalt-based amorphous wires, Cu-15.0 atomic percent (at. %) Sn shape-memory wires, and Ni{sub 2}MnGa (atomic percent) ferromagnetic wires were successfully produced by this method. The cobalt-based amorphous wire is flexible, and Cu-15.0 at. % Sn shape-memory wires have the tensile elongation of 14%. However, because of chemical reaction with glass and oxidation, it is hard to make Cu–Al–Ni shape-memory wires and Ni–Nb–Sn amorphous wires. Conditions for preparing these materials were summarized, and the differences of the solidification processes among glass-coated amorphous cobalt-based wires, Cu-15.0 at. % Sn shape-memory wires, and Ni{sub 2}MnGa wires were analyzed and discussed.

  9. Removing a sheet from the surface of a melt using elasticity and buoyancy

    DOE Patents [OSTI]

    Kellerman, Peter L.; Sun, Dawei; Helenbrook, Brian; Harvey, David S.

    2014-07-01

    Embodiments related to sheet production are disclosed. A melt of a material is cooled to form a sheet of the material on the melt. The sheet is formed in a first region at a first sheet height. The sheet is translated to a second region such that it has a second sheet height higher than the first sheet height. The sheet is then separated from the melt. A seed wafer may be used to form the sheet.

  10. IceCube Project Monthly Report November 2007

    E-Print Network [OSTI]

    Saffman, Mark

    the current budgets or the budgets modified by the cost performance index. Change Log - IceCube Total Project IceCube array with a detector uptime of 97%, above the internal monthly goal of 95%. #12;Cost design, development, procured materials, and the construction of the infrastructure that supports

  11. ENERGY BASED ICE COLLISION FORCES Claude Daley1

    E-Print Network [OSTI]

    Daley, Claude

    1 ENERGY BASED ICE COLLISION FORCES Claude Daley1 1 Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1C 3X5 ABSTRACT Ice collision forces can be determined by energy considerations. A variety of interaction geometry cases are considered. The indentation energy functions for eight different

  12. ENERGY BASED ICE COLLISION FORCES Claude Daley1

    E-Print Network [OSTI]

    Daley, Claude

    ENERGY BASED ICE COLLISION FORCES Claude Daley1 1 Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1C 3X5 ABSTRACT Ice collision forces can be determined by energy considerations. A variety of interaction geometry cases are considered. The indentation energy functions for eight different

  13. ORIGINAL ARTICLE Diatom assemblages promote ice formation in large

    E-Print Network [OSTI]

    Lee Jr., Richard E.

    (Oyserman et al., 2012; Twiss et al., 2012). Conducted during times of expansive ice cover, these surveys (Saxton et al., 2012; Twiss et al., 2012). The physical processes involved in the develop- ment of diatom demonstrated the presence of viable diatoms in meltwater from lake ice (Twiss et al., 2012), consistent

  14. Ice Storm Damage Greater Along the Terrestrial-Aquatic Interface

    E-Print Network [OSTI]

    Kraft, Clifford E.

    Ice Storm Damage Greater Along the Terrestrial-Aquatic Interface in Forested Landscapes Andrew A- tems. In 1998, a severe ice storm damaged over ten million hectares of forest across northern New York investigated the spatial arrangement of forest damage at the terrestrial-aquatic interface, an ecological edge

  15. Has the ice man arrived? Tact on the Internet

    E-Print Network [OSTI]

    Hearst, Marti

    Has the ice man arrived? Tact on the Internet Jonathan Grudin, UC Irvine and Microsoft Research resides in this extremely efficient spread of information. It is efficient, but it is not dis- crete. Eugene O'Neill's play The Ice Man Cometh outlines a series of calamities that occur when his characters

  16. CO diffusion into amorphous H2O ices

    E-Print Network [OSTI]

    Lauck, Trish; Shulenberger, Katherine; Rajappan, Mahesh; Oberg, Karin I; Cuppen, Herma M

    2015-01-01

    The mobility of atoms, molecules and radicals in icy grain mantles regulate ice restructuring, desorption, and chemistry in astrophysical environments. Interstellar ices are dominated by H2O, and diffusion on external and internal (pore) surfaces of H2O-rich ices is therefore a key process to constrain. This study aims to quantify the diffusion kinetics and barrier of the abundant ice constituent CO into H2O dominated ices at low temperatures (15-23 K), by measuring the mixing rate of initially layered H2O(:CO2)/CO ices. The mixed fraction of CO as a function of time is determined by monitoring the shape of the infrared CO stretching band. Mixing is observed at all investigated temperatures on minute time scales, and can be ascribed to CO diffusion in H2O ice pores. The diffusion coefficient and final mixed fraction depend on ice temperature, porosity, thickness and composition. The experiments are analyzed by applying Fick's diffusion equation under the assumption that mixing is due to CO diffusion into an i...

  17. 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

  18. Earth Planets Space, 57, 895902, 2005 Short time-scale heating of the Earth's mantle by ice-sheet dynamics

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    -scale energy transfer from the ice sheet loading and unloading processes to the Earth's interior via viscous flow can represent a non-negligible mantle energy source with cryogenic origins. Volumetric heating rebound. 1. Introduction The Earth is a nonlinear dynamical system with a fluid atmosphere and oceans

  19. Methods and apparatus for rotor blade ice detection

    DOE Patents [OSTI]

    LeMieux, David Lawrence

    2006-08-08

    A method for detecting ice on a wind turbine having a rotor and one or more rotor blades each having blade roots includes monitoring meteorological conditions relating to icing conditions and monitoring one or more physical characteristics of the wind turbine in operation that vary in accordance with at least one of the mass of the one or more rotor blades or a mass imbalance between the rotor blades. The method also includes using the one or more monitored physical characteristics to determine whether a blade mass anomaly exists, determining whether the monitored meteorological conditions are consistent with blade icing; and signaling an icing-related blade mass anomaly when a blade mass anomaly is determined to exist and the monitored meteorological conditions are determined to be consistent with icing.

  20. THE PHASES OF WATER ICE IN THE SOLAR NEBULA

    SciTech Connect (OSTI)

    Ciesla, Fred J.

    2014-03-20

    Understanding the phases of water ice that were present in the solar nebula has implications for understanding cometary and planetary compositions as well as the internal evolution of these bodies. Here we show that amorphous ice formed more readily than previously recognized, with formation at temperatures <70 K being possible under protoplanetary disk conditions. We further argue that photodesorption and freeze-out of water molecules near the surface layers of the solar nebula would have provided the conditions needed for amorphous ice to form. This processing would be a natural consequence of ice dynamics and would allow for the trapping of noble gases and other volatiles in water ice in the outer solar nebula.

  1. In situ apparatus for the study of clathrate hydrates relevant to solar system bodies using synchrotron X-ray diffraction and Raman spectroscopy

    E-Print Network [OSTI]

    Day, Sarah J; Evans, Aneurin; Parker, Julia E

    2015-01-01

    Clathrate hydrates are believed to play a significant role in various solar system environments, e.g. comets, and the surfaces and interiors of icy satellites, however the structural factors governing their formation and dissociation are poorly understood. We demonstrate the use of a high pressure gas cell, combined with variable temperature cooling and time-resolved data collection, to the in situ study of clathrate hydrates under conditions relevant to solar system environments. Clathrates formed and processed within the cell are monitored in situ using synchrotron X-ray powder diffraction and Raman spectroscopy. X-ray diffraction allows the formation of clathrate hydrates to be observed as CO2 gas is applied to ice formed within the cell. Complete conversion is obtained by annealing at temperatures just below the ice melting point. A subsequent rise in the quantity of clathrate is observed as the cell is thermally cycled. Four regions between 100-5000cm-1 are present in the Raman spectra that carry feature...

  2. The future of water, ice, snow underThe future of water, ice, snow under global warmingglobal warming

    E-Print Network [OSTI]

    Hurricane Katrina, the Kerry--Gingrich debate over globalGingrich debate over global warming, the local and regional warming.effects of global warming. Climate extends beyond temperature and rainfall, toClimate extendsThe future of water, ice, snow underThe future of water, ice, snow under global warmingglobal

  3. Observations of ice thickness and frazil ice in the St. Lawrence Island polynya from satellite imagery, upward looking sonar, and

    E-Print Network [OSTI]

    Washington at Seattle, University of

    with meteorological observations and a heat flux model. South of the island, we compare the ULS and thermalObservations of ice thickness and frazil ice in the St. Lawrence Island polynya from satellite, this paper examines the behavior of the Bering Sea St. Lawrence Island polynya using a combination

  4. Results from IceCube Mumbai, 11/12/12 Tom Gaisser for the IceCube Collab. 1

    E-Print Network [OSTI]

    Gaisser, Thomas K.

    Results from IceCube Mumbai, 11/12/12 Tom Gaisser for the IceCube Collab. 1 #12;2 39 Ins>tu>ons ~220 collaborators Mumbai, 11/12/12 Tom Gaisser-10 20 79 2010-11 7 86 Mumbai, 11/12/12 Tom Gaisser

  5. CO2 diffusion in polar ice: observations from naturally formed CO2 spikes in the Siple Dome (Antarctica) ice core

    E-Print Network [OSTI]

    Raggio Parkway, Reno, Nevada 89512-1095, USA ABSTRACT. One common assumption in interpreting ice-core CO2 records is that diffusion in the ice does not affect the concentration profile. However, this assumption/Ar and Kr/Ar), electrical conductivity and Ca2+ ion concentrations to show that substantial CO2 diffusion

  6. IntrAst1 (Petrovay) Chracteristics and origon of the Solar System SOLAR SYSTEM BODIES

    E-Print Network [OSTI]

    Petrovay, Kristóf

    ) Chracteristics and origon of the Solar System CHEMICAL DIFFERENTIATION IN THE SOLAR SYSTEM Chemical choose from theoretical models, based on empirical constraints. Constraints: > surface, gravity field mostly consist of ice. beyond r 30 AU methane ice also persists. Volatiles: gas or liquid at room

  7. Formation of Hydrogen, Oxygen, and Hydrogen Peroxide in Electron Irradiated Crystalline Water Ice

    E-Print Network [OSTI]

    Weijun Zheng; David Jewitt; Ralf I. Kaiser

    2005-11-18

    Water ice is abundant both astrophysically, for example in molecular clouds, and in planetary systems. The Kuiper belt objects, many satellites of the outer solar system, the nuclei of comets and some planetary rings are all known to be water-rich. Processing of water ice by energetic particles and ultraviolet photons plays an important role in astrochemistry. To explore the detailed nature of this processing, we have conducted a systematic laboratory study of the irradiation of crystalline water ice in an ultrahigh vacuum setup by energetic electrons holding a linear energy transfer of 4.3 +/- 0.1 keV mm-1. The irradiated samples were monitored during the experiment both on line and in situ via mass spectrometry (gas phase) and Fourier transform infrared spectroscopy (solid state). We observed the production of hydrogen and oxygen, both molecular and atomic, and of hydrogen peroxide. The likely reaction mechanisms responsible for these species are discussed. Additional formation routes were derived from the sublimation profiles of molecular hydrogen (90-140 K), molecular oxygen (147 -151 K) and hydrogen peroxide (170 K). We also present evidence on the involvement of hydroxyl radicals and possibly oxygen atoms as building blocks to yield hydrogen peroxide at low temperatures (12 K) and via a diffusion-controlled mechanism in the warming up phase of the irradiated sample.

  8. Ocean-ice/oil-weathering computer program user's manual. Final report

    SciTech Connect (OSTI)

    Kirstein, B.E.; Redding, R.T.

    1987-10-01

    The ocean-ice/oil-weathering code is written in FORTRAN as a series of stand-alone subroutines that can easily be installed on most any computer. All of the trial-and-error routines, integration routines, and other special routines are written in the code so that nothing more than the normal system functions such as EXP are required. The code is user-interactive and requests input by prompting questions with suggested input. Therefore, the user can actually learn about the nature of crude oil and oil weathering by using this code. The ocean-ice oil-weathering model considers the following weathering processes: evaporation; dispersion (oil into water); moussee (water into oil); and spreading; These processes are used to predict the mass balance and composition of oil remaining in the slick as a function of time and environmental parameters.

  9. Electrochemical reactions in a pure Na2SO4 melt

    SciTech Connect (OSTI)

    Fang, W.C.; Rapp, R.A.

    1983-12-01

    Cyclic voltammetry and chronopotentiometry were used to study the electrochemical reduction reactions of SO3 gas O2 and SO4S ions in a Na2SO4 melt at 900C. The reduction reaction of SO3 follows a ce mechanism: SO3 first reacts chemically with SO4S to form S2O7S and then proceeds via a one-electron electrochemical reduction reaction to form SO3 . The reduction of peroxide O2 ions forms either OS or both OS and superoxide O2S ions. Sulfate ions are subjected to decomposition at either very positive or very negative potentials. At very high positive potentials, sulfate ions decompose to evolve SO2 and O2 gases, in addition superoxide ions are also formed. At very negative potentials, sulfate ions decompose to form sulfide and peroxide. 24 references, 11 figures, 2 tables.

  10. Light absorption from particulate impurities in snow and ice determined by spectrophotometric analysis of filters

    SciTech Connect (OSTI)

    Grenfell, Thomas C.; Doherty, Sarah J.; Clarke, Antony D.; Warren, Stephen G.

    2011-05-10

    Light absorption by particulate impurities in snow and ice can affect the surface albedo and is important for the climate. The absorption properties of these particles can be determined by collecting and melting snow samples and extracting the particulate material by filtration of the meltwater. This paper describes the optical design and testing of a new instrument to measure the absorption spectrum from 400 to 750 nm wavelength of the particles collected on filters using an ''integrating-sandwich'' configuration. The measured absorption is shown to be unaffected by scattering of light from the deposited particulates. A set of calibration standards is used to derive an upper limit for the concentration of black carbon (BC) in the snow. The wavelength dependence of the absorption spectra from 450 to 600 nm is used to calculate an absorption Angstrom exponent for the aerosol. This exponent is used to estimate the actual BC concentration in the snow samples as well as the relative contributions of BC and non-BC constituents to the absorption of solar radiation integrated over the wavelength band 300 to 750 nm.

  11. Dissipation at tidal and seismic frequencies in a melt-free Moon U. H. Faul,2

    E-Print Network [OSTI]

    Nimmo, Francis

    Dissipation at tidal and seismic frequencies in a melt-free Moon F. Nimmo,1 U. H. Faul,2 and E. J. Successful models can reproduce the dissipation factor (Q) measured at both tidal and seismic frequencies, and the tidal Love numbers h2 and k2, without requiring any mantle melting. However, the frequency

  12. DSC Evidence for Microstructure and Phase Transitions in Polyethylene Melts at High Temperatures

    E-Print Network [OSTI]

    Hussein, Ibnelwaleed A.

    DSC Evidence for Microstructure and Phase Transitions in Polyethylene Melts at High Temperatures polyethylenes of types HDPE, LDPE, and LLDPE. DSC data were obtained for a range of heating and cooling rates previous rheology findings of order and high-temperature transitions in polyethylene melts. Introduction

  13. Melting and crystallization in Ni nanoclusters: The mesoscale regime Yue Qi and Tahir C agin

    E-Print Network [OSTI]

    Goddard III, William A.

    Melting and crystallization in Ni nanoclusters: The mesoscale regime Yue Qi and Tahir C¸ agin to a mesoscale nanocrystal regime well-defined bulk and surface properties above 750 atoms 2.7 nm . We find that the mesoscale nanocrystals melt via surface processes, leading to Tm,N Tm,bulk N 1/3 , dropping from Tm

  14. Low-melting elemental metal or fusible alloy encapsulated polymerization initiator for delayed initiation

    DOE Patents [OSTI]

    Hermes, Robert E.

    2015-12-22

    An encapsulated composition for polymerization includes an initiator composition for initiating a polymerization reaction, and a capsule prepared from an elemental metal or fusible alloy having a melting temperature from about 20.degree. C. to about 200.degree. C. A fluid for polymerization includes the encapsulated composition and a monomer. When the capsule melts or breaks open, the initiator is released.

  15. The Effect of Thermoplastics Melt Flow Behaviour on the Dynamics of Fire Growth 

    E-Print Network [OSTI]

    Sherratt, Jo

    of large-scale storage in warehouses, there is an uncertainty posed by large quantities of thermoplastic. Some forms of thermoplastic exhibit melt-flow behaviour when heated, and a large vertical array exposed to a fire may melt and ignite forming a pool...

  16. Investigation of residual stresses induced during the selective laser melting process

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    jean-claude.boyer@insa-lyon.fr Keywords: Selective laser melting, layer additional method, Residual stresses. Abstract. The selective laser melting process (SLM), belonging to the family of additive manufacturing processes, can create complex geometry parts from a CAD file. Previously, only prototypes were

  17. Comparisons of numerical modelling of the Selective Laser Melting Laurent VAN BELLE1, 2, a

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and arc additive layer manufacturing (WAALM), laser metal deposition (LMD), selective laser melting (SLM laser melting (SLM) first developed for rapid prototyping (RP) is now used for rapid manufacturing is based upon a double meshing with a multi step birth and death technique of manufactured part

  18. Glass science tutorial: Lecture No. 4, commercial glass melting and associated air emission issues

    SciTech Connect (OSTI)

    Kruger, A.A.

    1995-01-01

    This document serves as a manual for a workshop on commercial glass melting and associated air emission issues. Areas covered include: An overview of the glass industry; Furnace design and construction practices; Melting furnace operation; Energy input methods and controls; Air legislation and regulations; Soda lime emission mechanisms; and, Post furnace emission controls. Supporting papers are also included.

  19. ccsd-00001059(version1):26Jan2004 Continuous melting of compact polymers

    E-Print Network [OSTI]

    Boyer, Edmond

    ccsd-00001059(version1):26Jan2004 Continuous melting of compact polymers Jesper Lykke Jacobsen and bending rigidity in compact polymers can be ad- dressed within a lattice model introduced by P.J. Flory for polymers on surfaces, such as DNA adsorbed on a lipid bilayer. We predict a continuous melting transition

  20. Mullite Decomposition Kinetics and Melt Stabilization in the Temperature Range 19002000C

    E-Print Network [OSTI]

    Mitchell, Brian S.

    of mullite is as fiber reinforce- ment in high-temperature ceramic-matrix composites. Inviscid melt spinning2 composition was thus obtained, setting the groundwork for inviscid melt spin- ning mullite fiber making of the component phases of traditional ceramics and refractory materials, it is also a strong candidate material

  1. Generation of CO2-rich melts during basalt magma ascent and degassing

    E-Print Network [OSTI]

    Boyer, Edmond

    to solubilities. In contrast, the rate of vesiculation controls the final melt CO2 concentration. HighGeneration of CO2-rich melts during basalt magma ascent and degassing Michel Pichavant . Ida Di magma degassing, continuous decompressions of volatile-bearing (2.7-3.8 wt% H2O, 600-1300 ppm CO2

  2. Partially melted, mica-bearing crust in Central Tibet B. R. Hacker1

    E-Print Network [OSTI]

    Hacker, Bradley R.

    Partially melted, mica-bearing crust in Central Tibet B. R. Hacker1 , M. H. Ritzwoller2 , and J in the west than the east. The depth of the Curie temperature for magnetite inferred from satellite magnetic to deep crust consists of a mica-bearing residue from which melt has been extracted or is being extracted

  3. New mapping of kilometric anisotropies over the granulitic continental crust of Madagascar: melt -fluid migration and

    E-Print Network [OSTI]

    into the melt therefore Th spectrometric signal marks melt migration in the shear zone. The magnetic field is cause by magnetic mineral in the rocks. Low and high magnetic anomalies measured in nanotesla are associated with graphite mineralisations and disappearance of iron bearing minerals, high anomalies

  4. The anisotropic free energy of the Lennard-Jones crystal-melt interface James R. Morris

    E-Print Network [OSTI]

    Song, Xueyu

    The anisotropic free energy of the Lennard-Jones crystal-melt interface James R. Morris Metal; accepted 22 May 2003 We have calculated the free energy of the crystal-melt interface for the Lennard are in good agreement with previous calculations of the free energies, based upon simulations used

  5. The matching of 3D Rolie-Poly viscoelastic numerical simulations with experimental polymer melt flow

    E-Print Network [OSTI]

    Jimack, Peter

    Kingdom J. Embery and D. Auhl IRC in Polymer Science and Technology, Department of Physics and AstronomyThe matching of 3D Rolie-Poly viscoelastic numerical simulations with experimental polymer melt of commercial viscoelastic polymer melts. Numerical simulation techniques have steadily advanced over the last

  6. An FTIR Study of Hydrogen in Anorthosite and Associated Melt Inclusions

    SciTech Connect (OSTI)

    Seaman,S.; Dyar, M.; Marinkovic, N.; Dunbar, N.

    2006-01-01

    High-resolution Fourier transform infrared (FTIR) spectroscopy has been used to document the presence of hydrogen, to estimate its concentration, and to document its oxygen speciation in anorthoclase crystals and associated melt inclusions from Mount Erebus, Antarctica. Synchrotron-generated infrared radiation, 100 to 1000 times brighter than globar-generated infrared radiation, permits rapid collection of maps that depict relative intensities of a chosen FTIR band across the mapped area. Spectra and/or compositional maps showing variations in water concentration were collected from anorthoclase megacrysts and melt inclusions in the megacrysts. Studies of anorthoclase megacrysts involved collection of spectra from three mutually perpendicular sections cut from the crystals. FTIR spectra of anorthoclase crystals are characterized by a broad absorption band at approximately 3200 cm{sup -1} in the mid-IR range. The universal mass absorption coefficient for mid-IR range feldspar spectra, established by Johnson and Rossman (2003), was used for quantitative estimates of water concentrations in the feldspar crystals based on integrated area under the 3200 cm{sup -1} band. Water concentration in the anorthoclase sample was approximately 126 ppm, with an overall error of approximately {+-}30%. FTIR spectra of melt inclusions are characterized by a broad asymmetric absorption band at {approx}3550 cm{sup -1} that was used to calculate total water concentration. The absence of a band at 1630 cm{sup -1} suggests that water in the melt inclusions occurs as OH{sup -} rather than as molecular H{sub 2}O. Absorption coefficients established by Mandeville et al. (2002) for H species in glass were used to calculate water concentrations in the melt inclusions. Melt inclusions in the Mt. Erebus anorthoclase have water concentrations ranging from 0.12 to 0.39 wt%, with an overall error of approximately {+-}15%. The ratio of water in anorthoclase crystals to water in the melt from which the crystals formed, based on this study, and at these low melt water concentrations, is approximately 1:10. However, water concentration varies significantly from one melt inclusion to another, possibly suggesting initial melt water heterogeneity. Maps of water concentration show that variations in water concentration within melt inclusions are associated with fractures that cut the melt inclusions and in some cases do not extend out into surrounding crystals or into crystal inclusions. Thin ({approx}50 {micro}m thick) zones of elevated water concentrations on the boundaries of the crystals in contact with melt inclusions suggest that water has diffused into the crystals from the melt inclusions.

  7. Photodesorption of ices I: CO, N2 and CO2

    E-Print Network [OSTI]

    Karin I. Oberg; Ewine F. van Dishoeck; Harold Linnartz

    2009-01-23

    A longstanding problem in astrochemistry is how molecules can be maintained in the gas phase in dense inter- and circumstellar regions. Photodesorption is a non-thermal desorption mechanism, which may explain the small amounts of observed cold gas in cloud cores and disk mid-planes. This paper aims to determine the UV photodesorption yields and to constrain the photodesorption mechanisms of three astrochemically relevant ices: CO, N2 and CO2. In addition, the possibility of co-desorption in mixed and layered CO:N2 ices is explored. The ice photodesorption is studied experimentally under ultra high vacuum conditions and at 15-60 K using a hydrogen discharge lamp (7-10.5 eV). The ice desorption during irradiation is monitored by reflection absorption infrared spectroscopy of the ice and simultaneous mass spectrometry of the desorbed molecules. Both the UV photodesorption yields per incident photon and the photodesorption mechanisms are molecule specific. CO photodesorbs without dissociation from the surface layer of the ice. N2, which lacks an electronic transition in this wavelength range, has a photodesorption yield that is more than an order of magnitude lower. This yield increases significantly due to co-desorption when N2 is mixed in with or layered on top of CO ice. CO2 photodesorbs through dissociation and subsequent recombination from the top 10 layers of the ice. At low temperatures (15-18 K) the derived photodesorption yields are 2.7x10^-3 and CO2 photodesorption yield is 1.2x10^-3x(1-e^(-X/2.9)) + 1.1x10^-3x(1-e^(-X/4.6)) molecules photon-1, where X is the ice thickness in monolayers and the two parts of the expression represent a CO2 and CO photodesorption pathway.

  8. MEASUREMENT OF THE SHOCK-HEATED MELT CURVE OF LEAD USING PYROMETRY AND REFLECTOMETRY

    SciTech Connect (OSTI)

    D. Partouche-Sebban and J. L. Pelissier, Commissariat a` l'Energie Atomique,; F. G. Abeyta, Los Alamos National Laboratory; W. W. Anderson, Los Alamos National Laboratory; M. E. Byers, Los Alamos National Laboratory; D. Dennis-Koller, Los Alamos National Laboratory; J. S. Esparza, Los Alamos National Laboratory; S. D. Borror, Bechtel Nevada; C. A. Kruschwitz, Bechtel Nevada

    2004-01-01

    Data on the high-pressure melting temperatures of metals is of great interest in several fields of physics including geophysics. Measuring melt curves is difficult but can be performed in static experiments (with laser-heated diamond-anvil cells for instance) or dynamically (i.e., using shock experiments). However, at the present time, both experimental and theoretical results for the melt curve of lead are at too much variance to be considered definitive. As a result, we decided to perform a series of shock experiments designed to provide a measurement of the melt curve of lead up to about 50 GPa in pressure. At the same time, we developed and fielded a new reflectivity diagnostic, using it to make measurements on tin. The results show that the melt curve of lead is somewhat higher than the one previously obtained with static compression and heating techniques.

  9. Gas ageice age differences and the chronology of the Vostok ice core, M. L. Bender,1

    E-Print Network [OSTI]

    Chappellaz, Jérôme

    Gas age­ice age differences and the chronology of the Vostok ice core, 0­100 ka M. L. Bender,1 G. [1] Gas is trapped in polar ice at depths of $50­120 m and is therefore significantly younger than cores (Vostok, Dome Fuji, and Dome C). We recorrelate the gas records of Vostok and Greenland Ice Sheet

  10. Fast numerical method for growth and retreat of subsurface ice on Mars Norbert Schorghofer

    E-Print Network [OSTI]

    Schörghofer, Norbert

    ice, retreat of pore ice, retreat of an ice sheet, and retreat of pore ice due to geothermal heating) Dtexpl: vertical spatial resolution and D the diffusion coef- ficient. The vertical grid spacing needs to be finer than the diurnal skin depth of the temperature cycle. The diurnal

  11. Modelling the reorientation of sea-ice faults as the wind changes direction

    E-Print Network [OSTI]

    Feltham, Daniel

    Modelling the reorientation of sea-ice faults as the wind changes direction Alexander V. WILCHINSKY-1290, USA ABSTRACT. A discrete-element model of sea ice is used to study how a 908 change in wind direction alters the pattern of faults generated through mechanical failure of the ice. The sea-ice domain is 400

  12. A Model of Viscoelastic Ice-Shelf Flexure

    E-Print Network [OSTI]

    MacAyeal, Douglas R.; Sergienko, Olga V.; Banwell, Alison F.

    2015-07-15

    -shelf and ice-stream motion and stress fields. Examples of these phenomena27 include tide-driven grounding-line flexure and migration [e.g., Sayag and Worster, 2013, Tsai and28 Gudmundsson, 2015], tidally pulsed grounding line ice velocity variations [e... -shelf flexure that is applicable to circumstances where the114 ratio of vertical to horizontal length scales, H and L, respectively, is small (H/L ? 1), and where115 the vertical displacement (assumed constant through the depth of the ice shelf) due to flexure...

  13. Fast and slow crystal growth kinetics in glass-forming melts

    SciTech Connect (OSTI)

    Orava, J.; Greer, A. L., E-mail: alg13@cam.ac.uk [WPI-Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan and Department of Materials Science and Metallurgy, 27 Charles Babbage Road, University of Cambridge, Cambridge CB3 0FS (United Kingdom)

    2014-06-07

    Published values of crystal growth rates are compared for supercooled glass-forming liquids undergoing congruent freezing at a planar crystal-liquid interface. For the purposes of comparison pure metals are considered to be glass-forming systems, using data from molecular-dynamics simulations. For each system, the growth rate has a maximum value U{sub max} at a temperature T{sub max} that lies between the glass-transition temperature T{sub g} and the melting temperature T{sub m}. A classification is suggested, based on the lability (specifically, the propensity for fast crystallization), of the liquid. High-lability systems show “fast” growth characterized by a high U{sub max}, a low T{sub max}?/?T{sub m}, and a very broad peak in U vs. T?/?T{sub m}. In contrast, systems showing “slow” growth have a low U{sub max}, a high T{sub max}?/?T{sub m}, and a sharp peak in U vs. T?/?T{sub m}. Despite the difference of more than 11 orders of magnitude in U{sub max} seen in pure metals and in silica, the range of glass-forming systems surveyed fit into a common pattern in which the lability increases with lower reduced glass-transition temperature (T{sub g}?/?T{sub m}) and higher fragility of the liquid. A single parameter, a linear combination of T{sub g}?/?T{sub m} and fragility, can show a good correlation with U{sub max}. For all the systems, growth at U{sub max} is coupled to the atomic/molecular mobility in the liquid. It is found that, across the diversity of glass-forming systems, T{sub max}?/?T{sub g} = 1.48 ± 0.15.

  14. Microphysical Consequences of the Spatial Distribution of Ice Nucleation in Mixed-Phase Stratiform Clouds

    SciTech Connect (OSTI)

    Yang, Fan; Ovchinnikov, Mikhail; Shaw, Raymond A.

    2014-07-28

    Mixed-phase stratiform clouds can persist even with steady ice precipitation fluxes, and the origin and microphysical properties of the ice crystals are of interest. Vapor deposition growth and sedimentation of ice particles along with a uniform volume source of ice nucleation, leads to a power law relation between ice water content wi and ice number concentration ni with exponent 2.5. The result is independent of assumptions about the vertical velocity structure of the cloud and is therefore more general than the related expression of Yang et al. [2013]. The sensitivity of the wi-ni relationship to the spatial distribution of ice nucleation is confirmed by Lagrangian tracking and ice growth with cloud-volume, cloud-top, and cloud-base sources of ice particles through a time-dependent cloud field. Based on observed wi and ni from ISDAC, a lower bound of 0.006 m^3/s is obtained for the ice crystal formation rate.

  15. Minimalist Model of Ice Microphysics in Mixed-phase Stratiform Clouds

    SciTech Connect (OSTI)

    Yang, F.; Ovchinnikov, Mikhail; Shaw, Raymond A.

    2013-07-28

    The question of whether persistent ice crystal precipitation from super cooled layer clouds can be explained by time-dependent, stochastic ice nucleation is explored using an approximate, analytical model, and a large-eddy simulation (LES) cloud model. The updraft velocity in the cloud defines an accumulation zone, where small ice particles cannot fall out until they are large enough, which will increase the residence time of ice particles in the cloud. Ice particles reach a quasi-steady state between growth by vapor deposition and fall speed at cloud base. The analytical model predicts that ice water content (wi) has a 2.5 power law relationship with ice number concentration ni. wi and ni from a LES cloud model with stochastic ice nucleation also confirm the 2.5 power law relationship. The prefactor of the power law is proportional to the ice nucleation rate, and therefore provides a quantitative link to observations of ice microphysical properties.

  16. Ice Concentration Retrieval in Stratiform Mixed-phase Clouds Using Cloud Radar Reflectivity Measurements and 1D Ice Growth Model Simulations

    SciTech Connect (OSTI)

    Zhang, Damao; Wang, Zhien; Heymsfield, Andrew J.; Fan, Jiwen; Luo, Tao

    2014-10-01

    Measurement of ice number concentration in clouds is important but still challenging. Stratiform mixed-phase clouds (SMCs) provide a simple scenario for retrieving ice number concentration from remote sensing measurements. The simple ice generation and growth pattern in SMCs offers opportunities to use cloud radar reflectivity (Ze) measurements and other cloud properties to infer ice number concentration quantitatively. To understand the strong temperature dependency of ice habit and growth rate quantitatively, we develop a 1-D ice growth model to calculate the ice diffusional growth along its falling trajectory in SMCs. The radar reflectivity and fall velocity profiles of ice crystals calculated from the 1-D ice growth model are evaluated with the Atmospheric Radiation Measurements (ARM) Climate Research Facility (ACRF) ground-based high vertical resolution radar measurements. Combining Ze measurements and 1-D ice growth model simulations, we develop a method to retrieve the ice number concentrations in SMCs at given cloud top temperature (CTT) and liquid water path (LWP). The retrieved ice concentrations in SMCs are evaluated with in situ measurements and with a three-dimensional cloud-resolving model simulation with a bin microphysical scheme. These comparisons show that the retrieved ice number concentrations are within an uncertainty of a factor of 2, statistically.

  17. Reliable Distributed Computing for Decision Support Systems

    E-Print Network [OSTI]

    Bargiela, Andrzej

    of pipes and network nodes spread over a large geographical area, calls for a control of computational system it is serv- icing. Addressing the reliability issues of dis- tributed systems involves tackling

  18. 1 | De-icing salt damage to trees | November 2011 Pathology Advisory Note

    E-Print Network [OSTI]

    1 | De-icing salt damage to trees | November 2011 Pathology Advisory Note (No. 11) De-icing salt damage to trees De-icing Salt Damage to Trees Joan F Webber, David R Rose, Martin C Dobson #12;2 | De-icing salt damage to trees | November 2011 S a l t D a m a g e De-icing Salt Damage Introduction Rock salt

  19. Evaluation of expected solar flare neutrino events in the IceCube observatory

    E-Print Network [OSTI]

    de Wasseige, G; Hanson, K; van Eijndhoven, N; Klein, K -L

    2015-01-01

    Since the end of the eighties and in response to a reported increase in the total neutrino flux in the Homestake experiment in coincidence with a solar flare, solar neutrino detectors have searched for solar flare signals. Neutrinos from the decay of mesons, which are themselves produced in collisions of accelerated protons with the solar atmosphere, would provide a novel window on the underlying physics of the acceleration process. For our studies we focus on the IceCube Neutrino Observatory, a cubic kilometer neutrino detector located at the geographical South Pole. Due to its Supernova data acquisition system and its DeepCore component, dedicated to low energy neutrinos, IceCube may be sensitive to solar flare neutrinos and thus permit either a measurement of the signal or the establishment of more stringent upper limits on the solar flare neutrino flux. We present an approach for a time profile analysis based on a stacking method and an evaluation of a possible solar flare signal in IceCube using the Gean...

  20. Dynamics and pattern selection at the crystal-melt interface. Progress report No. 4, March 1, 1989--February 28, 1990

    SciTech Connect (OSTI)

    Cummins, H.Z.

    1990-12-31

    This report discusses: light scattering at the crystal-melt interface; morphological instability and pattern selection; and sidebranching.