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Sample records for lsc floorplan lsc

  1. LSC Users Manual David W. Ignat

    E-Print Network [OSTI]

    of the computer program LSC was funded by the United States Department of Energy, Oce of Fusion Energy, under Usage 18 3.1 Preliminaries . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3.2 Description

  2. LSC Users Manual David W. Ignat

    E-Print Network [OSTI]

    of the computer program LSC was funded by the United States Department of Energy, Office of Fusion Energy, under Usage 18 3.1 Preliminaries . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3.2 Description

  3. The LSC Glitch Group : Monitoring Noise Transients during the fifth LIGO Science Run

    E-Print Network [OSTI]

    L. Blackburn; L. Cadonati; S. Caride; S. Caudill; S. Chatterji; N. Christensen; J. Dalrymple; S. Desai; A. Di Credico; G. Ely; J. Garofoli; L. Goggin; G. González; R. Gouaty; C. Gray; A. Gretarsson; D. Hoak; T. Isogai; E. Katsavounidis; J. Kissel; S. Klimenko; R. A. Mercer; S. Mohapatra; S. Mukherjee; F. Raab; K. Riles; P. Saulson; R. Schofield; P. Shawhan; J. Slutsky; J. R. Smith; R. Stone; C. Vorvick; M. Zanolin; N. Zotov; J. Zweizig


    The LIGO Scientific Collaboration (LSC) glitch group is part of the LIGO detector characterization effort. It consists of data analysts and detector experts who, during and after science runs, collaborate for a better understanding of noise transients in the detectors. Goals of the glitch group during the fifth LIGO science run (S5) included (1) offline assessment of the detector data quality, with focus on noise transients, (2) veto recommendations for astrophysical analysis and (3) feedback to the commissioning team on anomalies seen in gravitational wave and auxiliary data channels. Other activities included the study of auto-correlation of triggers from burst searches, stationarity of the detector noise and veto studies. The group identified causes for several noise transients that triggered false alarms in the gravitational wave searches; the times of such transients were identified and vetoed from the data generating the LSC astrophysical results.

  4. Linear Vlasov solver for microbunching gain estimation with inclusion of CSR, LSC and linac geometric impedances

    E-Print Network [OSTI]

    Tsai, Cheng-Ying; Li, Rui; Tennant, Chris


    As is known, microbunching instability (MBI) has been one of the most challenging issues in designs of magnetic chicanes for short-wavelength free-electron lasers or linear colliders, as well as those of transport lines for recirculating or energy recovery linac machines. To more accurately quantify MBI in a single-pass system and for more complete analyses, we further extend and continue to increase the capabilities of our previously developed linear Vlasov solver [1] to incorporate more relevant impedance models into the code, including transient and steady-state free-space and/or shielding coherent synchrotron radiation (CSR) impedances, the longitudinal space charge (LSC) impedances, and the linac geometric impedances with extension of the existing formulation to include beam acceleration [2]. Then, we directly solve the linearized Vlasov equation numerically for microbunching gain amplification factor. In this study we apply this code to a beamline lattice of transport arc [3] following an upstream linac...

  5. United States Geological Survey, LSC | 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 DeliciousPlasmaP a g eWorks -09-0018-CXNuonYuchengRichlands,project activitiesCommerce Jump to: navigation,UnitedUnited

  6. Temperature Dependent Wire Delay Estimation in Floorplanning

    E-Print Network [OSTI]

    Nannarelli, Alberto

    Temperature Dependent Wire Delay Estimation in Floorplanning Andreas Thor Winther, Wei Liu, Alberto, Arizona State University, Tempe, USA Abstract--Due to large variations in temperature in VLSI cir- cuits and the linear relationship between metal resistance and temperature, the delay through wires of the same length


    E-Print Network [OSTI]

    Young, Evangeline Fun Yu

    with flexibility in shape, we show that there exists a slicing floorplan F such that area(F) 5 min{(l + & ), 2, (1 + cr)}Atotoz where Atotal is the total area of all the modules, A,,, is the maximum module area, (Y= J floorplans. As a re- sult, slicing floorplans are used in many existing floorplan- ning systems [4, 3, 6, 51

  8. Net Balanced Floorplanning Based on Elastic Energy Model

    E-Print Network [OSTI]

    Nannarelli, Alberto

    Net Balanced Floorplanning Based on Elastic Energy Model Wei Liu and Alberto Nannarelli Dept variations can introduce extra signal skew, it is desirable to have floorplans with balanced net delays based on the elastic energy model. The B*-tree, which is based on an ordered binary tree, is used

  9. Unification of Partitioning, Placement and Floorplanning Saurabh N. Adya

    E-Print Network [OSTI]

    Markov, Igor

    to solve the more general placement problem, which in- cludes cell placement, floorplanning, mixed-size placement and achi- eving routability. At every step of min-cut placement, either parti- tioning to 70% by 2005, and 90% by 2011. This growth is mostly fueled by chips for high-bandwidth communication

  10. Thermal Signature: A Simple Yet Accurate Thermal Index for Floorplan Optimization

    E-Print Network [OSTI]

    Sapatnekar, Sachin

    methods have been proposed for fast thermal analysis, and have been integrated in thermalThermal Signature: A Simple Yet Accurate Thermal Index for Floorplan Optimization ABSTRACT evaluation should be done extremely fast with high accuracy. A new thermal index, named thermal signature

  11. Bus-Aware Microarchitectural Floorplanning Dae Hyun Kim Sung Kyu Lim

    E-Print Network [OSTI]

    Lim, Sung Kyu

    and long, thereby consuming significant area, delay, and power. In our architecture, we have 51 buses on other important floorplanning objectives including area, performance, power, and thermal. We developed on area, performance, and power objectives under thermal constraint. I. INTRODUCTION Microarchitectural

  12. Oxygen Transport Ceramic Membranes Quarterly Report

    E-Print Network [OSTI]

    Eagar, Thomas W.

    . Processing of perovskites of LSC, LSF and LSCF composition were continued for evaluation of mechanical

  13. Facility Floorplan

    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:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article) | SciTech Connect Journal Article: X-rayContract Documents PPPL TheA

  14. Chromium (III), Titanium (III), and Vanadium (IV) sensitization of rare earth complexes for luminescent solar concentrator applications

    E-Print Network [OSTI]

    Thompson, Nicholas John


    High optical concentrations without excess heating in a stationary system can be achieved with a luminescent solar concentrator (LSC). Neodymium (Nd) and ytterbium (Yb) are excellent infrared LSC materials: inexpensive, ...

  15. Methods for measurement of heterogeneous materials with laser-induced breakdown spectroscopy (LIBS)

    E-Print Network [OSTI]

    Effenberger, Andrew Jay


    pulse laser-induced breakdown spectroscopy ICCD – intensified charge-coupled device LSC – laser-supported combustion

  16. Collective behavior of semiconductor nanoparticles for use in solar energy harvesting

    E-Print Network [OSTI]

    Shcherbatyuk, Georgiy


    as the normalized short circuit current (I LSC ) generatedwhere I PV is the short circuit current generated by the PV

  17. Engineering Exploration Day Saturday, February 13, 2010

    E-Print Network [OSTI]

    Rutledge, Steven

    Engineering Exploration Day Saturday, February 13, 2010 Fort Collins, Colorado #12;2 EXPLORATION Engineering, Dr. Ken Reardon LSC Room 224-226 Electrical & Computer Engineering, Karen Ungerer LSC Room 228 Environmental Engineering, Dr. Sybil Sharvelle LSC Room 230 Mechanical Engineering, Dr. Patrick Fitzhorn


    E-Print Network [OSTI]

    our purposes: · Serial LSC LDC communication is simulated using Altera transceivers · LSC gains another channel (thus, "dual-output" HOLA) · Another LDC+ROMB block was added to receive data from the second channel. FEMB, LDC, and ROMB were simulated functionally, while LSC (including Altera transceiver

  19. Hadronic production of thermal photons 

    E-Print Network [OSTI]

    Turbide, S.; Rapp, Ralf; Gale, C.


    )]. ................................................................................ 11? Figure 2-5. Internal Strain Gage Locations on Transverse Reinforcement, Concrete Core, and Concrete Cover [taken from Alberson (2009)]. .......................... 12? Figure 2-6. Brass Insert with Tip Installed in the Surface of the LSC [taken...-7. Transverse and Longitudinal Strain Locations on the LSC Specimens? Small Face 1 and Large Face 1 during the Initial Orientation. .................... 26? Figure 3-8. Transverse Surface Strains on the LSC Specimens? Small Face 1 and Large Face 1...

  20. Integration formulas via the Legendre-Fenchel Subdifferential of ...

    E-Print Network [OSTI]


    setting of locally convex spaces, the above integration formula was established in [15] for proper lsc convex functions. Moreover, a criterion using only the exact ...

  1. GrGrfico de Controle por Atributosfico de Controle por Atributos VVctorctor HugoHugo LachosLachos DDvilavila

    E-Print Network [OSTI]

    Lachos, Victor

    número observado de itens não conformes. Uma estimativa da fração não conforme é : n pp pLSC pLM n pp p,0 )1( 3 05,0 096,0 25 95,005,0 305,0 )1( 3 = × -= - -= == = × += - += n pp pLSC pLM n pp pLSC #12 controle para fração não conforme: i i n pp pLIC pLM n pp pLSC )1( 3 )1( 3 - -= = - += = = = m i i m i i

  2. GREENHOUSE GAS (GHG) INVENTORY REPORT 20102011 Dalhousie Office of Sustainability

    E-Print Network [OSTI]

    Brownstone, Rob

    Caption. LSC Solar thermal panels installed 20102011. #12;Page | 1 TableofContents Table ......................................................................................... 35 Appendix I: Nova Scotia Power Emission Factors ......

  3. Radiation-Detection Instrument Registration RSO Form 51 (11/04)

    E-Print Network [OSTI]

    Wilcock, William

    GM Based Exposure Rate (EXP) instrument ­ e.g. Xetex, GM Dose Rate Moveable Plug-In Ion Chamber (IC radiation-detection instrument - e.g. MCA, gas-flow ion chamber, MDH 3. Instrument Data Readout Unit LSC, GC only): Detector Unit: Type (Check One): GM NaI ZnS LSC Ion Chamber Other Manufacturer: Serial

  4. HOLA status February 2011 What's been done

    E-Print Network [OSTI]

    to set up a test stand What needs to be done: Finish up a full FEMB/LSC/LDC/ROMB testbench in Modelsim chip (DAQ LDC) Serial connection (via optical transceiver) FPGA provides a parallel interface transceiver) (only forward channel shown) TLK2501 chip (FTK LDC) TLK2501 chip (DAQ LDC) OLD LSC CORE (altera

  5. Dye-doped polymer nanoparticles for flexible, bulk luminescent solar concentrators

    E-Print Network [OSTI]

    Rosenberg, Ron, S.B. Massachusetts Institute of Technology


    Bulk luminescent solar concentrators (LSC) cannot make use of Forster resonance energy transfer (FRET) due to necessarily low dye concentrations. In this thesis, we attempt to present a poly-vinylalcohol (PVA) waveguide ...

  6. Analysis of a small sample geometry for concurrent identification and quantification of mixed-nuclide samples 

    E-Print Network [OSTI]

    Krieger, Kenneth Vincent


    sample, each emitting a different type of radiation. High purity germanium detectors (HPGe) and liquid scintillation counters (LSC) can be used to quantify activities of several known sources. This can be done without buying more or expensive equipment...

  7. Applications of non-imaging micro-optic systems

    E-Print Network [OSTI]

    Baker, Katherine Anne


    LIST OF ABBREVIATIONS AR CPV CSP DEP F F/# ITO LSC Nm PMSCadapt the solar concentrator for CSP using (a) two parabolicfor concentrated solar power (CSP), also known as solar

  8. Three-dimensional flow structures and dynamics of turbulent thermal convection in a cylindrical cell

    E-Print Network [OSTI]

    Tong, Penger

    , such as the mean velocity profile in the LSC plane, the boundary layer thickness and its scaling with Ra and Pr and organize their motions spatially between the top and bottom plates, leading to an oscillatory motion

  9. A Case Study Examination of an Engineering Articulation Process between a Community College and a University 

    E-Print Network [OSTI]

    Phillips, Claire


    college engineering science programs F 2 F Face to face FOS Field of study FTC First time in college (student) LSC, Lone Star Lone Star College (System) OECD Organization for Economic Cooperation and Development SACS Southern Association of Colleges...

  10. Engineering Exploration Day Schedule 8:00 a.m. -9:00 a.m. -Registration/Check-In Lory Student Center 228 (All Tracks)

    E-Print Network [OSTI]

    -2 · Biomedical/Chemical & Biological Engineering Lab ­ Nanostructured Biopolymers for Tissue Engineering ­ SCOTT/Mechanical Engineering Lab ­ Biomaterials Surface Micro/Nano-Engineering Laboratory - SCOTT 367 · Chemical & Biological Engineering Overview ­ Dr. Matt Kipper, Associate Professor ­ LSC Cherokee Ballroom · Chemical & Biological

  11. Electrochemically-Controlled Compositional Oscillations of Oxide Surfaces

    SciTech Connect (OSTI)

    Mutoro, Eva [Massachusetts Institute of Technology (MIT); Crumlin, Ethan [Massachusetts Institute of Technology (MIT); Pöpke, Hendrik [Institute of Physical Chemistry, Justus-Liebig-University Giessen; Luerssen, Bjoern [Institute of Physical Chemistry, Justus-Liebig-University Giessen; Amati, Matteo [Sincrotrone Trieste Elettra; Abyaneh, Majid [Sincrotrone Trieste, Basovizza, Italy; Biegalski, Michael D [ORNL; Christen, Hans M [ORNL; Gregoratti, Luca [Sincrotrone Trieste, Basovizza, Italy; Janek, Jürgen [Institute of Physical Chemistry, Justus-Liebig-University Giessen; Shao-Horn, Yang [Massachusetts Institute of Technology (MIT)


    Perovskite oxides can exhibit a wide range of interesting characteristics such as being catalytically active and electronically and/or ionically conducting, and thus they have been used in a number of solid-state devices such as solid oxide fuel cells and sensors. As the surface compositions of perovskites can greatly influence the catalytic properties, knowing and controlling their surface chemistries is crucial to enhance device performance. In this study, we demonstrate that the surface strontium (Sr) and cobalt (Co) concentrations of perovskite-based thin films can be controlled reversibly at elevated temperatures by applying small electrical potential biases. The surface chemistry changes of La0.8Sr0.2CoO3 (LSC113), LaSrCoO4 (LSC214), and LSC214-decorated LSC113 films (LSC113/214) were investigated in situ by utilizing synchrotron-based X-ray photoelectron spectroscopy (XPS), where the largest changes of surface Sr was found for the LSC113/214 surface. These findings offer the potential of reversibly controlling the surface functionality of perovskites.

  12. FABSYN: Floorplan-aware bus architecture synthesis

    E-Print Network [OSTI]

    Pasricha, S; Dutt, N D; Bozorgzadeh, E; Ben-Romdhane, M


    on-chip communication architectures,” in Proc. CODES-ISSS,application-speci?c architectures for heterogeneous multi-the SoC communication architecture design space,” in Proc.

  13. Lighting system combining daylight concentrators and an artificial source

    DOE Patents [OSTI]

    Bornstein, Jonathan G. (Miami, FL); Friedman, Peter S. (Toledo, OH)


    A combined lighting system for a building interior includes a stack of luminescent solar concentrators (LSC), an optical conduit made of preferably optical fibers for transmitting daylight from the LSC stack, a collimating lens set at an angle, a fixture for receiving the daylight at one end and for distributing the daylight as illumination inside the building, an artificial light source at the other end of the fixture for directing artifical light into the fixture for distribution as illumination inside the building, an automatic dimmer/brightener for the artificial light source, and a daylight sensor positioned near to the LSC stack for controlling the automatic dimmer/brightener in response to the daylight sensed. The system also has a reflector positioned behind the artificial light source and a fan for exhausting heated air out of the fixture during summer and for forcing heated air into the fixture for passage into the building interior during winter.

  14. Simulation of a cascaded longitudinal space charge amplifier for broadband radiation production using a superconducting linac

    E-Print Network [OSTI]

    Halavanau, A


    Longitudinal space charge (LSC) effects are generally considered as harmful in free-electron lasers as they can seed unfavorable energy modulations that can result in density modulations with associated emittance dilution. It was pointed out, however, that such "micro-bunching instabilities'' could be potentially useful to support the generation of broadband coherent radiation. Therefore there has been an increasing interest in devising accelerator beam lines capable of controlling LSC induced density modulations. In the present paper we augment these previous investigations by combining a grid-less space charge algorithm with the popular particle-tracking program {\\sc elegant}. This high-fidelity model of the space charge is used to benchmark conventional LSC models. We finally employ the developed model to optimize the performance of a cascaded longitudinal space charge amplifier using beam parameters comparable to the ones achievable at Fermilab Accelerator Science \\& Technology (FAST) facility current...

  15. Full Spectrum Diffused and Beamed Solar Energy Application Using Optical Fibre

    E-Print Network [OSTI]

    Dutta Majumdar, M R


    Existing solar energy application systems use small fraction of full spectrum of solar energy. So attempts are made to show how full spectrum solar energy can be used for diffused and beamed form of incident solar energy. Luminescent Solar Concentrator (LSC) principle with optical fibre in diffused sun light and dielectric mirror separation technique with optical fibre in beamed form are discussed. Comparison of both the cases are done. Keywords: full spectrum, solar photonics, diffused solar energy, beamed solar energy, LSC, dielectric mirror, optical fibre, Photo-Voltaic

  16. The Generic Graph Component Library Dr. Dobb's Journal September 2000

    E-Print Network [OSTI]

    Lumsdaine, Andrew

    by Jeremy G. Siek and Andrew Lumsdaine). The most important aspect of designing the library was to defineThe Generic Graph Component Library Dr. Dobb's Journal September 2000 Generic programming for, and, respectively. The Standard Template Library has established a solid foundation

  17. The Centre for Blood Research Dr. Scott Tebbutt

    E-Print Network [OSTI]

    Strynadka, Natalie

    The Centre for Blood Research Dr. Scott Tebbutt Associate Professor, UBC Chief Scientific Officer, October 3, 2012 12:00 pm in LSC3 Life Sciences Centre 2350 Health Sciences Mall "Blood-based signatures, CBR Director, Professor of Medicine, UBC Peripheral whole blood is often the sample of choice

  18. The Centre for Blood Research Seminar Series

    E-Print Network [OSTI]

    Strynadka, Natalie

    The Centre for Blood Research Seminar Series Wednesday, April 24th, 2013 LSC 3 - Life Sciences Red Blood Cells" The glycoprotein, Band 3 or anion exchanger 1 (AE1) catalyzes the electro per cell, similar to Glycophorin A with which it interacts forming the Wright (Wr) blood group antigen

  19. The Centre for Blood Research Seminar Series

    E-Print Network [OSTI]

    Strynadka, Natalie

    The Centre for Blood Research Seminar Series Wednesday, March 13th, 2013 LSC 3 - Life Sciences "PARticipating in Metalloprotease Signaling in Blood Vessels" When plaques coating blood vessel walls rupture and expose collagen, platelets spring into action to form a blood clot at the damaged site. Dr. Kuliopulois

  20. Revised for 2012-2013 Find the Biology Curricula on the Web At

    E-Print Network [OSTI]

    Raina, Ramesh

    on Environmental Sciences BA Degree in Biology BS Degree in Biochemistry BS Degree in Biotechnology Minor.S. Biotechnology; B.S. Biology with Focus in Environmental Sciences; and a Minor in Biology. Short. Douglas Frank, Undergraduate Advisor for BS with Environmental Focus Room 446, LSC, 443-4529 dafrank

  1. Test of the consistency of various linearized semiclassical initial value time correlation functions in application to inelastic neutron scattering

    E-Print Network [OSTI]

    Miller, William H.

    functions in application to inelastic neutron scattering from liquid para-hydrogen Jian Liua and William H for inelastic neutron scattering from liquid para-hydrogen at 14 K. Various time correlations functions were neutron scattering experimental data all suggest that the LSC-IVR is indeed a good short

  2. Advances in Micro-Scale Laser Peening Technology Y. Lawrence Yao, Wenwu Zhang, and Hongqiang Chen

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    . In modeling improvements, plasma expansion is modeled as laser supported combustion wave, in which radial laser supported combustion (LSC) wave [3]. The 1D results are then modified to consider spatial by an intense (>1GW/cm2 ) laser pulse, the surface layer instantane- ously vaporizes into a high temperature

  3. Cycling and Transit Green Buildings

    E-Print Network [OSTI]

    Lotze, Heike K.

    solar thermal panels at the LSC. 2. Solar wall on the Mona Campbell Bld. 3. 80 solar Photovoltaic (PV) panels installed in front of a solar wall system on the roof of the Computer Science Bld. Water certified Mona Campbell Bld using the green directory and signs or watch our video. Features include a rain

  4. Plant, Cell and Environment {^992) 15, 471-477 Hydraulic architecture of sugarcane in relation to patterns of

    E-Print Network [OSTI]

    Neufeld, Howard S.

    transpiration were also measured in intact plants as a function of plant size. Leaf specific hydraulic surface area; E, transpiration per unit leaf area; L, hydraulic conductance; Lsc. leaf specific as the hydraulic conductance (L) per unit segment length L = q/{AP/Ax) (1) where q is the rate of water flow

  5. Verifying a Virtual Component Interface-based PCI Bus Wrapper Using an

    E-Print Network [OSTI]

    Verifying a Virtual Component Interface-based PCI Bus Wrapper Using an LSC-Based Specification Peripheral Component Interface (PCI) transaction as the VSIA expected integrators to use the VCI standard safety properties. We then specify both the VCI protocol and the PCI protocol using Live Sequence Charts

  6. The Centre for Blood Research Seminar Series

    E-Print Network [OSTI]

    Strynadka, Natalie

    The Centre for Blood Research Seminar Series Wednesday, July 17th, 2013 LSC 3 - Life Sciences. The latter represents challenges in regard to cost, safety, ecological friendliness, and process equipment that including >50 mM salts such as NaCitrate with 8 to 10% (w/w) solutions of PAA allowed for almost complete

  7. Stochastic 3D Modeling of La0.6Sr0.4CoO3-Cathodes Based on Structural Segmentation of FIB-SEM Images

    E-Print Network [OSTI]

    Schmidt, Volker

    Graph, SOFC, Sphere Representation, Watershed Transformation 1. Introduction In this paper the microstructure of La0.6Sr0.4CoO3- (LSC) cathodes in solid oxide fuel cells (SOFC) is investigated. For classical SOFC electrodes (e.g. Ni- YSZ anodes or LSM-YSZ cathodes) microstructure effects are widely discussed


    E-Print Network [OSTI]

    control from FTK D[16] @ 100 MHz #12;Testbench 6 A similar testbench (with two LDC+ROMB receivers) was implemented in Mentor Graphics Modelsim. FEMB, LDC, and ROMB were simulated functionally, while LSC ­ using (based on S32PCI64): · Implements S-LINK protocol · Provides access to S-LINK via PCI bus 8 S-LINK LDC


    E-Print Network [OSTI]

    Knowles, David William

    LASER SAFETY COMMITTEE CHARTER November, 2005 Function The Safety Review Committee (SRC) performs-committees to address specific health and safety matters. The Laser Safety Committee (LSC) is one of the SRC expert sub-committees. The Laser SafetyCommittee recommends policies and practices regarding the conduct and regulatory compliance


    E-Print Network [OSTI]

    ELECTRICAL & COMPUTER ENGINEERING SEMINAR "Geometry as a Prior in Signal Processing" by Yuejie Chi Electrical Engineering Princeton University Monday, March 19, 2012, 11:00 a.m. Location LSC 210 Abstract processing. Biography: Yuejie Chi is a Ph.D. candidate in Electrical Engineering at Princeton University


    E-Print Network [OSTI]

    ELECTRICAL & COMPUTER ENGINEERING SEMINAR "Considerations for Curriculum Planning and Revitalization in Engineering" by Prof. Michael A. de Miranda School of Education and Department of Electrical and Computer Engineering Colorado State University Monday, Feb. 20, 2012, 11:00 a.m. Location: LSC 210 Abstract

  12. Cathode side hardware for carbonate fuel cells

    DOE Patents [OSTI]

    Xu, Gengfu (Danbury, CT); Yuh, Chao-Yi (New Milford, CT)


    Carbonate fuel cathode side hardware having a thin coating of a conductive ceramic formed from one of LSC (La.sub.0.8Sr.sub.0.2CoO.sub.3) and lithiated NiO (Li.sub.xNiO, where x is 0.1 to 1).

  13. Monte-Carlo simulations of light propagation in luminescent solar concentrators based on semiconductor nanoparticles

    E-Print Network [OSTI]

    Ilan, Boaz

    Monte-Carlo simulations of photon transport to predict the performance of LSCs based on "type-II" CdSe. In addition, when the LSC has CdSe-CdTe nanorods that are aligned perpendicular to the top surface, the escape.1063/1.3619809] I. INTRODUCTION Photovoltaic (PV) solar cells have become much more efficient over the past few

  14. Greenhouse Policies and Procedures Dept. of Biology

    E-Print Network [OSTI]

    Raina, Ramesh

    Greenhouse Policies and Procedures Dept. of Biology Syracuse University Implemented 1 March 2012 Greenhouse manager: Paul Logue Greenhouse Committee: David Althoff, Heather Coleman, Jason Fridley, Paul Logue #12;2 Facilities The state of the art greenhouse on the 5th floor of LSC has ten independently

  15. Passport to Leadership Series Course Descriptions 11/2011 Passport to Leadership Series

    E-Print Network [OSTI]

    New Mexico, University of

    Passport to Leadership Series Course Descriptions 11/2011 Passport to Leadership Series Course # Course Title Description LSC100 Essentials of Leadership This course is intended for individuals with leadership/management experience. Learn the challenges of leadership today; be introduced to the interaction

  16. Characterization of marine exopolymeric substance (EPS) responsible for binding of thorium (IV) isotopes 

    E-Print Network [OSTI]

    Alvarado Quiroz, Nicolas Gabriel


    for technical assistance. I personally would like to give my gratitude to the deliverEdocs and Interlibrary Loan (ILL) Services and Thesis office at Texas A&M University, College Station for their prompt turnaround time. Finally, I give thanks to my family....3 Liquid Scintillation Counting (LSC) - 14C, 32P, 35S and 234Th(IV) ............49 III.3.4 Determination of Organic Phosphate and Sulphate by Ion Chromatography (IC)......................................................................50 III.3...

  17. Performance of La0.8Sr0.2CoO3 coated NiO as cathodes for molten carbonate fuel cells

    E-Print Network [OSTI]

    Popov, Branko N.

    Performance of La0.8Sr0.2CoO3 coated NiO as cathodes for molten carbonate fuel cells Prabhu Ganesan.2CoO3; Nickel oxide 1. Introduction The molten carbonate fuel cell (MCFC) is a promising power current density of 160 mA/cm2 . The LSC­NiO shows promise as an alternate cathode in molten carbonate fuel

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

    E-Print Network [OSTI]

    Weiss, Stephan


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

  19. Advanced Measurement and Modeling Techniques for Improved SOFC Cathodes

    SciTech Connect (OSTI)

    Stuart Adler; L. Dunyushkina; S. Huff; Y. Lu; J. Wilson


    The goal of this project was to develop an improved understanding of factors governing performance and degradation of mixed-conducting SOFC cathodes. Two new diagnostic tools were developed to help achieve this goal: (1) microelectrode half-cells for improved isolation of cathode impedance on thin electrolytes, and (2) nonlinear electrochemical impedance spectroscopy (NLEIS), a variant of traditional impedance that allows workers to probe nonlinear rates as a function of frequency. After reporting on the development and efficacy of these tools, this document reports on the use of these and other tools to better understand performance and degradation of cathodes based on the mixed conductor La{sub 1-x}Sr{sub x}CoO{sub 3-{delta}} (LSC) on gadolinia or samaria-doped ceria (GDC or SDC). We describe the use of NLEIS to measure O{sub 2} exchange on thin-film LSC electrodes, and show that O{sub 2} exchange is most likely governed by dissociative adsorption. We also describe parametric studies of porous LSC electrodes using impedance and NLEIS. Our results suggest that O{sub 2} exchange and ion transport co-limit performance under most relevant conditions, but it is O{sub 2} exchange that is most sensitive to processing, and subject to the greatest degradation and sample-to-sample variation. We recommend further work that focuses on electrodes of well-defined or characterized geometry, and probes the details of surface structure, composition, and impurities. Parallel work on primarily electronic conductors (LSM) would also be of benefit to developers, and to improved understanding of surface vs. bulk diffusion.

  20. An Analysis of A Low-Energy, Low-Water Use Community in Mexico City 

    E-Print Network [OSTI]

    Bermudez Alcocer, Jose Luis


    . Apartment Type A Access Floorplan with Lightwells (De Anda, 1952). ...........104 Figure 35. Apartment Type A Lower (or Upper) Floorplan with Lightwells. ......................105 Figure 36. Floorplan with Lightwells and Zones...

  1. Development of an expert system for generating optimum floorplans for VLSI circuits 

    E-Print Network [OSTI]

    Mehta, Ketan R


    in the implementation of my system is also discussed. A. CURRENT VLSI DESIGN SYSTEMS The Hughes Automated Layout System The Hughes Automated Layout System (HAL) is an example of an in-house, custom built system for the specific needs of an organization... to thank my parents and my brother for their support and encouragement throughout my study at Texas A & M University. TABLE OF CONTENTS CHAPTER Page INTRODUCTION A. CURRENT VLSI DESIGN SYSTEMS The Hughes Automated Layout System Timberwolf Placement...

  2. Status of ArDM-1t: First observations from operation with a full ton-scale liquid argon target

    E-Print Network [OSTI]

    ArDM Collaboration; J. Calvo; C. Cantini; M. Daniel; U. Degunda; S. Di Luise; L. Epprecht; A. Gendotti; S. Horikawa; L. Knecht; B. Montes; W. Mu; M. Munoz; S. Murphy; G. Natterer; K. Nguyen; K. Nikolics; L. Periale; C. Regenfus; L. Romero; A. Rubbia; R. Santorelli; F. Sergiampietri; D. Sgalaberna; T. Viant; S. Wu


    ArDM-1t is the first operating ton-scale liquid argon detector for direct search of Dark Matter particles. Developed at CERN as Recognized Experiment RE18, the experiment has been approved in 2010 to be installed in the Spanish underground site LSC (Laboratorio Subterraneo de Canfranc). Under the label of LSC EXP-08-2010 the ArDM detector underwent an intensive period of technical completion and safety approval until the recent filling of the target vessel with almost 2 ton of liquid argon. This report describes the experimental achievements during commissioning of ArDM and the transition into a stage of first physics data taking in single phase operational mode. We present preliminary observations from this run. A first indication for the background discrimination power of LAr detectors at the ton-scale is shown. We present an outlook for completing the detector with the electric drift field and upgrade of the scintillation light readout system with novel detector modules based on SiPMs in order to improve the light yield.

  3. Lowering the background level and the energy threshold of Micromegas x-ray detectors for axion searches

    E-Print Network [OSTI]

    F. J. Iguaz; S. Aune; F. Aznar; J. F. Castel; T. Dafni; M. Davenport; E. Ferrer-Ribas; J. Galan; J. A. Garcia; J. G. Garza; I. Giomataris; I. G. Irastorza; T. Papaevangelou; A. Rodriguez; A. Tomas; T. Vafeiadis; S. C. Yildiz


    Axion helioscopes search for solar axions by their conversion in x-rays in the presence of high magnetic fields. The use of low background x-ray detectors is an essential component contributing to the sensitivity of these searches. In this work, we review the recent advances on Micromegas detectors used in the CERN Axion Solar Telescope (CAST) and proposed for the future International Axion Observatory (IAXO). The actual setup in CAST has achieved background levels below 10$^{-6}$ keV$^{-1}$ cm$^{-2}$ s$^{-1}$, a factor 100 lower than the first generation of Micromegas detectors. This reduction is based on active and passive shielding techniques, the selection of radiopure materials, offline discrimination techniques and the high granularity of the readout. We describe in detail the background model of the detector, based on its operation at CAST site and at the Canfranc Underground Laboratory (LSC), as well as on Geant4 simulations. The best levels currently achieved at LSC are low than 10$^{-7}$ keV$^{-1}$ cm$^{-2}$ s$^{-1}$ and show good prospects for the application of this technology in IAXO. Finally, we present some ideas and results for reducing the energy threshold of these detectors below 1 keV, using high-transparent windows, autotrigger electronics and studying the cluster shape at different energies. As a high flux of axion-like-particles is expected in this energy range, a sub-keV threshold detector could enlarge the physics case of axion helioscopes.

  4. 90Sr liquid scintillation urine analysis utilizing different approaches for tracer recovery.

    SciTech Connect (OSTI)

    Piraner, Olga [Centers for Disease Control and Prevention, Atlanta, GA; Preston, Rose T. [Sandia Staffing Alliance, LLC, Albuquerque, NM; Shanks, Sonoya Toyoko; Jones, Robert [Centers for Disease Control and Prevention, Atlanta, GA


    90Sr is one of the isotopes most commonly produced by nuclear fission. This medium lived isotope presents serious challenges to radiation workers, the environment, and following a nuclear event, the general public. Methods of identifying this nuclide have been in existence for a number of years (e.g. Horwitz, E.P. [1], Maxwell, S.L.[2], EPA 905.0 [3]) which are time consuming, requiring a month or more for full analysis. This time frame is unacceptable in the present security environment. It is therefore important to have a dependable and rapid method for the determination of Sr. The purposes of this study are to reduce analysis time to less than half a day by utilizing a single method of radiation measurement while continuing to yield precise results. This paper presents findings on three methods that can meet this criteria; (1) stable Sr carrier, (2) 85Sr by gamma spectroscopy, and (3) 85Sr by LSC. Two methods of analyzing and calculating the 85Sr tracer recovery were investigated (gamma spectroscopy and a low energy window-Sr85LEBAB by LSC) as well as the use of two different types of Sr tracer (85Sr and stable Sr carrier). Three separate stock blank urine samples were spiked with various activity levels of 239Pu, 137Cs, 90Sr /90Y to determine the effectiveness of the Eichrome Sr-spec%C2%AE resin 2mL extractive columns. The objective was to compare the recoveries of 85Sr versus a stable strontium carrier, attempt to compare the rate at which samples can be processed by evaluating evaporation, neutralization, and removing the use of another instrument (gamma spectrometer) by using the LSC spectrometer to obtain 85Sr recovery. It was found that when using a calibration curve comprised of a different cocktail and a non-optimum discriminator setting reasonable results (bias of %C2%B1 25%) were achieved. The results from spiked samples containing 85Sr demonstrated that a higher recovery is obtained when using gamma spectroscopy (89-95%) than when using the LEB window from LSC (120-470%). The high recovery for 85Sr by LSC analysis may be due to the interference/cross talk from the alpha region since alpha counts were observed in all sample sets. After further investigation it was determined that the alpha counts were due to 239Pu breakthrough on the Sr-spec%C2%AE column. This requires further development to purify the Sr before an accurate tracer recovery determination can be made. Sample preparation times varied and ranged from 4-6 hours depending on the specific sample preparation process. The results from the spiked samples containing stable strontium nitrate Sr(NO3)2 carrier demonstrate that gravimetric analysis yields the most consistent high recoveries (97-101%) when evaporation is carefully performed. Since this method did not have a variation on the tracer recovery method, the samples were counted in 1) LEB/Alpha/Beta mode optimized for Sr-90, 2) DPM for Sr-90, and 3) general LEB/Alpha/Beta mode. The results (from the known) ranged from 79-104%, 107-177%, and 85-89% for 1, 2, and 3 respectively. Counting the prepared samples in a generic low energy beta/alpha/beta protocol yielded more accurate and consistent results and also yielded the shortest sample preparation turn-around-time of 3.5 hours.

  5. Local Sensitivity of Predicted CO2 Injectivity and Plume Extent to Model Inputs for the FutureGen 2.0 site

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

    Zhang, Z. Fred; White, Signe K.; Bonneville, Alain; Gilmore, Tyler J.


    Numerical simulations have been used for estimating CO2 injectivity, CO2 plume extent, pressure distribution, and Area of Review (AoR), and for the design of CO2 injection operations and monitoring network for the FutureGen project. The simulation results are affected by uncertainties associated with numerous input parameters, the conceptual model, initial and boundary conditions, and factors related to injection operations. Furthermore, the uncertainties in the simulation results also vary in space and time. The key need is to identify those uncertainties that critically impact the simulation results and quantify their impacts. We introduce an approach to determine the local sensitivity coefficientmore »(LSC), defined as the response of the output in percent, to rank the importance of model inputs on outputs. The uncertainty of an input with higher sensitivity has larger impacts on the output. The LSC is scalable by the error of an input parameter. The composite sensitivity of an output to a subset of inputs can be calculated by summing the individual LSC values. We propose a local sensitivity coefficient method and applied it to the FutureGen 2.0 Site in Morgan County, Illinois, USA, to investigate the sensitivity of input parameters and initial conditions. The conceptual model for the site consists of 31 layers, each of which has a unique set of input parameters. The sensitivity of 11 parameters for each layer and 7 inputs as initial conditions is then investigated. For CO2 injectivity and plume size, about half of the uncertainty is due to only 4 or 5 of the 348 inputs and 3/4 of the uncertainty is due to about 15 of the inputs. The initial conditions and the properties of the injection layer and its neighbour layers contribute to most of the sensitivity. Overall, the simulation outputs are very sensitive to only a small fraction of the inputs. However, the parameters that are important for controlling CO2 injectivity are not the same as those controlling the plume size. The three most sensitive inputs for injectivity were the horizontal permeability of Mt Simon 11 (the injection layer), the initial fracture-pressure gradient, and the residual aqueous saturation of Mt Simon 11, while those for the plume area were the initial salt concentration, the initial pressure, and the initial fracture-pressure gradient. The advantages of requiring only a single set of simulation results, scalability to the proper parameter errors, and easy calculation of the composite sensitivities make this approach very cost-effective for estimating AoR uncertainty and guiding cost-effective site characterization, injection well design, and monitoring network design for CO2 storage projects.« less


    E-Print Network [OSTI]

    Chang, Yao-Wen

    not correspond to most real designs. Further, it does not consider interconnection cost which is a crucial metric placements and interconnection costs. Our floorplanner with the estimated uncertain data can effectively the dimensions and interconnections of modules are not fully determined. In this paper, we propose a sequence

  7. The NEXT experiment: A high pressure xenon gas TPC for neutrinoless double beta decay searches

    E-Print Network [OSTI]

    D. Lorca; J. Martín-Albo; F. Monrabal; for the NEXT Collaboration


    Neutrinoless double beta decay is a hypothetical, very slow nuclear transition in which two neutrons undergo beta decay simultaneously and without the emission of neutrinos. The importance of this process goes beyond its intrinsic interest: an unambiguous observation would establish a Majorana nature for the neutrino and prove the violation of lepton number. NEXT is a new experiment to search for neutrinoless double beta decay using a radiopure high-pressure xenon gas TPC, filled with 100 kg of Xe enriched in Xe-136. NEXT will be the first large high-pressure gas TPC to use electroluminescence readout with SOFT (Separated, Optimized FuncTions) technology. The design consists in asymmetric TPC, with photomultipliers behind a transparent cathode and position-sensitive light pixels behind the anode. The experiment is approved to start data taking at the Laboratorio Subterr\\'aneo de Canfranc (LSC), Spain, in 2014.

  8. STAG UK Newsletter Issue 3

    E-Print Network [OSTI]

    al C01..1.litC.uvnl. ll L.irL:. uGo!J:putsr, t~liG is CnptlxLn JDllCB .,~irk ~Jf t~lC: uGG Lntcrpr-lsc ? .c)oe,in thirty SGC0YlU c,Ju(ltclo't,m.Cocio zoro~ zoro ?'oro,duGtruct zoro. 1! COL?p. 11'lll1.irty :J(. CUllI.1Bo ?? 00 ??? 1 Ki~$pock .? Ki...,lor tho bonofi t of our over scc,s ~,:.()r.ibvrs9 BooD is Dri tish DrvadcuBtinL Corporo.tion? affcctiolllcltcly l:no\\,Til as "Auntyl! ,'Tholl sJ.J.c? D been Lood. Thln~,s nrc looking v.p for tho club! ll.t tllC last count'lHc had. 43 Ueu()crs 1r.:.nc1...

  9. Characterization of Atomic and Electronic Structures of Electrochemically Active SOFC Cathode Surfaces

    SciTech Connect (OSTI)

    Kevin Blinn; Yongman Choi; Meilin Liu


    The objective of this project is to gain a fundamental understanding of the oxygen-reduction mechanism on mixed conducting cathode materials by means of quantum-chemical calculations coupled with direct experimental measurements, such as vibrational spectroscopy. We have made progress in the elucidation of the mechanisms of oxygen reduction of perovkite-type cathode materials for SOFCs using these quantum chemical calculations. We established computational framework for predicting properties such as oxygen diffusivity and reaction rate constants for adsorption, incorporation, and TPB reactions, and formulated predictions for LSM- and LSC-based cathode materials. We have also further developed Raman spectroscopy as well as SERS as a characterization tool for SOFC cathode materials. Raman spectroscopy was used to detect chemical changes in the cathode from operation conditions, and SERS was used to probe for pertinent adsorbed species in oxygen reduction. However, much work on the subject of unraveling oxygen reduction for SOFC cathodes remains to be done.


    SciTech Connect (OSTI)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana


    In the present quarter, experiments are presented on ceramic/metal interactions of Zirconia/Ni-B-Si system and with a thin Ti coating deposited on zirconia surface. Processing of perovskites of LSC, LSF and LSCF composition for evaluation of mechanical properties as a function of environment are begun. The studies are to be in parallel with LSFCO composition to characterize the segregation of cations and slow crack growth in environmental conditions. La{sub 1-x}Sr{sub x}FeO{sub 3-d} has also been characterized for paramagnetic ordering at room temperature and the evolution of magnetic moments as a function of temperature are investigated. Investigation on the thermodynamic properties of the membrane materials are continued to develop a complete model for the membrane transport.

  11. Light Collection in the Prototypes of the ANAIS Dark Matter Project

    E-Print Network [OSTI]

    Amaré, Julio; Cuesta, Clara; García, Eduardo; Martínez, María; Oliván, Miguel A; Ortigoza, Ysrael; de Solórzano, Alfonso Ortíz; Pobes, Carlos; Puimedón, Jorge; Sarsa, María Luisa; Villar, José Ángel; Villar, Patricia


    The ANAIS experiment aims at the confirmation of the DAMA/LIBRA signal using the same target and technique at the Canfranc Underground Laboratory (LSC) in Spain. ANAIS detectors consist of large NaI crystals coupled to two photomultipliers (PMTs). In this work we present Single Electron Response (SER) data for several units of the Hamamatsu R12669SEL2 PMT model extracted from normal operation data of ANAIS underground prototypes and we compare them with PMT SER characterization previously done at surface lab before coupling them to NaI crystal. Moreover, total light collection for different ANAIS prototypes has been calculated, producing an excellent average result of 15 phe/keV, which has a good impact in both energy resolution and threshold.

  12. Managing Research Data in Big Science

    E-Print Network [OSTI]

    Norman Gray; Tobia Carozzi; Graham Woan


    The project which led to this report was funded by JISC in 2010--2011 as part of its 'Managing Research Data' programme, to examine the way in which Big Science data is managed, and produce any recommendations which may be appropriate. Big science data is different: it comes in large volumes, and it is shared and exploited in ways which may differ from other disciplines. This project has explored these differences using as a case-study Gravitational Wave data generated by the LSC, and has produced recommendations intended to be useful variously to JISC, the funding council (STFC) and the LSC community. In Sect. 1 we define what we mean by 'big science', describe the overall data culture there, laying stress on how it necessarily or contingently differs from other disciplines. In Sect. 2 we discuss the benefits of a formal data-preservation strategy, and the cases for open data and for well-preserved data that follow from that. This leads to our recommendations that, in essence, funders should adopt rather light-touch prescriptions regarding data preservation planning: normal data management practice, in the areas under study, corresponds to notably good practice in most other areas, so that the only change we suggest is to make this planning more formal, which makes it more easily auditable, and more amenable to constructive criticism. In Sect. 3 we briefly discuss the LIGO data management plan, and pull together whatever information is available on the estimation of digital preservation costs. The report is informed, throughout, by the OAIS reference model for an open archive.

  13. Synchrotron Investigations of SOFC Cathode Degradation

    SciTech Connect (OSTI)

    Idzerda, Yves


    The atomic variations occurring in cathode/electrolyte interface regions of La{sub 1-x}Sr{sub x}Co{sub y}Fe{sub 1-y}O{sub 3-?} (LSCF) cathodes and other SOFC related materials have been investigated and characterized using soft X-ray Absorption Spectroscopy (XAS) and diffuse soft X-ray Resonant Scattering (XRS). X-ray Absorption Spectroscopy in the soft X-ray region (soft XAS) is shown to be a sensitive technique to quantify the disruption that occurs and can be used to suggest a concrete mechanism for the degradation. For LSC, LSF, and LSCF films, a significant degradation mechanism is shown to be Sr out-diffusion. By using the XAS spectra of hexavalent Cr in SrCrO4 and trivalent Cr in Cr2O3, the driving factor for Sr segregation was identified to be the oxygen vacancy concentration at the anode and cathode side of of symmetric LSCF/GDC/LSCF heterostructures. This is direct evidence of vacancy induced cation diffusion and is shown to be a significant indicator of cathode/electrolyte interfacial degradation. X-ray absorption spectroscopy is used to identify the occupation of the A-sites and B-sites for LSC, LSF, and LSCF cathodes doped with other transition metals, including doping induced migration of Sr to the anti-site for Sr, a significant cathode degradation indicator. By using spatially resolved valence mapping of Co, a complete picture of the surface electrochemistry can be determined. This is especially important in identifying degradation phenomena where the degradation is spatially localized to the extremities of the electrochemistry and not the average. For samples that have electrochemical parameters that are measured to be spatially uniform, the Co valence modifications were correlated to the effects of current density, overpotential, and humidity.

  14. B9783rdFLOORPLAN E.O. Lawrence Berkeley National Laboratory -Building 978: JBEI & ABPDU, 5885 Hollis Street, Suite 320 & 400, Berkeley, CA 94608 -WASTE QUANTITIES

    E-Print Network [OSTI]

    Eisen, Michael

    50% 108-95-2 551 chloroform 50% 67-66-3 VACUUM PUMP OIL oil - 100% 000826-00-0 N N C WASTE LIQ 221 - Building 978: JBEI & ABPDU, 5885 Hollis Street, Suite 320 & 400, Berkeley, CA 94608 - WASTE QUANTITIES 9 8 Max Ave Ann Common Name Cas N Secret EHS Class Mix State Haz Cat Waste days Cont Unit Daily Daily

  15. Selective Extraction of Uranium from Liquid or Supercritical Carbon Dioxide

    SciTech Connect (OSTI)

    Farawila, Anne F.; O'Hara, Matthew J.; Wai, Chien M.; Taylor, Harry Z.; Liao, Yu-Jung


    Current liquid-liquid extraction processes used in recycling irradiated nuclear fuel rely on (1) strong nitric acid to dissolve uranium oxide fuel, and (2) the use of aliphatic hydrocarbons as a diluent in formulating the solvent used to extract uranium. The nitric acid dissolution process is not selective. It dissolves virtually the entire fuel meat which complicates the uranium extraction process. In addition, a solvent washing process is used to remove TBP degradation products, which adds complexity to the recycling plant and increases the overall plant footprint and cost. A liquid or supercritical carbon dioxide (l/sc -CO2) system was designed to mitigate these problems. Indeed, TBP nitric acid complexes are highly soluble in l/sc -CO2 and are capable of extracting uranium directly from UO2, UO3 and U3O8 powders. This eliminates the need for total acid dissolution of the irradiated fuel. Furthermore, since CO2 is easily recycled by evaporation at room temperature and pressure, it eliminates the complex solvent washing process. In this report, we demonstrate: (1) A reprocessing scheme starting with the selective extraction of uranium from solid uranium oxides into a TBP-HNO3 loaded Sc-CO2 phase, (2) Back extraction of uranium into an aqueous phase, and (3) Conversion of recovered purified uranium into uranium oxide. The purified uranium product from step 3 can be disposed of as low level waste, or mixed with enriched uranium for use in a reactor for another fuel cycle. After an introduction on the concept and properties of supercritical fluids, we first report the characterization of the different oxides used for this project. Our extraction system and our online monitoring capability using UV-Vis absorbance spectroscopy directly in sc-CO2 is then presented. Next, the uranium extraction efficiencies and kinetics is demonstrated for different oxides and under different physical and chemical conditions: l/sc -CO2 pressure and temperature, TBP/HNO3 complex used, reductant or complexant used for selectivity, and ionic liquids used as supportive media. To complete the extraction and recovery cycle, we then demonstrate uranium back extraction from the TBP loaded sc-CO2 phase into an aqueous phase and the characterization of the uranium complex formed at the end of this process. Another aspect of this project was to limit proliferation risks by either co-extracting uranium and plutonium, or by leaving plutonium behind by selectively extracting uranium. We report that the former is easily achieved, since plutonium is in the tetravalent or hexavalent oxidation state in the oxidizing environment created by the TBP-nitric acid complex, and is therefore co-extracted. The latter is more challenging, as a reductant or complexant to plutonium has to be used to selectively extract uranium. After undertaking experiments on different reducing or complexing systems (e.g., AcetoHydroxamic Acid (AHA), Fe(II), ascorbic acid), oxalic acid was chosen as it can complex tetravalent actinides (Pu, Np, Th) in the aqueous phase while allowing the extraction of hexavalent uranium in the sc-CO2 phase. Finally, we show results using an alternative media to commonly used aqueous phases: ionic liquids. We show the dissolution of uranium in ionic liquids and its extraction using sc-CO2 with and without the presence of AHA. The possible separation of trivalent actinides from uranium is also demonstrated in ionic liquids using neodymium as a surrogate and diglycolamides as the extractant.

  16. STAG UK Newsletter Issue 3 

    E-Print Network [OSTI]

    :.> Lokci for 50~OOO YOaro 7 11011 8toP980 ~lC coulet cQpturG 11i1>1 tDl~o 'LiL! l.>ack to Cheroll i\\)r trial, 111ho tHO IJ.< D. c')uplq of fiL,ltts al.ward tIl() Lntorprise, mid L.ir1-: thre1.~tGllo to biol1 U1) tIle ship .. rlllJcro tll...0. 2l.ul enLaced. i1..lT,'}i tint :Ci11al C01..1.litC.uvnl. ll L.irL:. uGo!J:putsr, t~liG is CnptlxLn JDllCB .,~irk ~Jf t~lC: uGG Lntcrpr-lsc ? .c)oe,in thirty SGC0YlU c,Ju(ltclo't,m.Cocio zoro~ zoro ?'oro,duGtruct zoro. 1! COL?p. 11'lll1.irty :J...

  17. Mitigation Plans for the Microbunching-Instability-Related COTR at ASTA/FNAL

    SciTech Connect (OSTI)

    Lumpkin, A. H.; Johnson, A. M.


    At the Advanced Superconducting Test Accelerator (ASTA) now under construction at Fermilab, we anticipate the appearance of the microbunching instability related to the longitudinal space charge (LSC) impedances. With a photoinjector source and up to two chicane compressors planned, the conditions should result in the shift of some microbunched features into the visible light regime. The presence of longitudinal microstructures (microbunching) in the electron beam or the leading edge spikes can result in strong, spatially localized coherent enhancements of optical transition radiation (COTR) that mask the actual beam profile. Several efforts on mitigation of the effects in the diagnostics task have been identified. At ASTA we have designed the beam profiling stations to have mitigation features based on spectral filtering, scintillator choice, and the timing of the trigger to the digital camera's CCD chip. Since the COTR is more intense in the NIR than UV we have selectable bandpass filters centered at 420 nm which also overlap the spectral emissions of the LYSO:Ce scintillators. By delaying the CCD trigger timing of the integration window by 40-50 ns, we can reject the prompt OTR signal and integrate on the delayed scintillator light predominately. This combination of options should allow mitigation of COTR enhancements of order 100-1000 in the distribution.

  18. Waste properties of a strippable coating used for the TMI-2 reactor building decontamination

    SciTech Connect (OSTI)

    Dougherty, D.R.; Adams, J.W.; Barletta, R.E.


    Strippable coating material considered for use in the TMI-2 reactor building decontamination has been tested for Sr, Cs, and Co leachability, for radiation stability, and for resistance to biodegradation. It was also immersion tested in water, a water solution saturated with toluene and xylene, toluene, xylene, and liquid scintillation counting (LSC) cocktail. Leach testing, performed using a modified IAEA procedure, resulted in all of the Cs and Co activity and most of the Sr activity being released from the coating in just a few days. Immersion resulted in swelling of the coating in all of the liquids tested. Gamma irradiation of the coating did not produce any apparent physical changes in the coating to a dose of 1 x 10/sup 8/ rad, however, radiolytic gas generation of H/sub 2/, CO, and CO/sub 2/ was observed. Biodegradation testing was performed in soil samples from the Barnwell, South Carolina, and Hanford, Washington, low-level waste disposal sites. These test results indicate that strippable coating radwaste of itself will not meet the requirements for stabilized Class B waste outlined in 10 CFR 61 (proposed) and the NRC Draft Branch Technical Position on Waste Form.

  19. Strippable coating used for the TMI-2 reactor building decontamination

    SciTech Connect (OSTI)

    Adams, J.W.; Dougherty, D.R.; Barletta, R.E.


    Strippable coating material used in the TMI-2 reactor building decontamination has been tested for Sr, Cs, and Co leachability, for radiation stability, thermal stability, and for resistance to biodegradation. It was also immersion tested in water, a water solution saturated with toluene and xylene, toluene, xylene, and liquid scintillation counting (LSC) cocktail. Leach testing resulted in all of the Cs and Co activity and most of the Sr activity being released from the coating in just a few days. Immersion resulted in swelling of the coating in all of the liquids tested. Gamma irradiation and heating of the coating did not produce any apparent physical changes in the coating to 1 x 10/sup 8/ rad and 100/sup 0/C; however, gas generation of H/sub 2/, CO, CO/sub 2/ was observed in both cases. Biodegradation of the coating occurred readily in soils as indicated by monitoring CO/sub 2/ produced from microbial respiration. These test results indicate that strippable coating radwaste would have to be stabilized to meet the requirements for Class B waste outlined in 10 CFR Part 61 and the NRC Draft Technical Position on Waste Form.

  20. NEXT-100 Technical Design Report (TDR). Executive Summary

    E-Print Network [OSTI]

    NEXT Collaboration; V. Álvarez; F. I. G. M. Borges; S. Cárcel; J. M. Carmona; J. Castel; J. M. Catalá; S. Cebrián; A. Cervera; D. Chan; C. A. N. Conde; T. Dafni; T. H. V. T. Dias; J. Díaz; M. Egorov; R. Esteve; P. Evtoukhovitch; L. M. P. Fernandes; P. Ferrario; A. L. Ferreira; E. Ferrer-Ribas; E. D. C. Freitas; V. M. Gehman; A. Gil; I. Giomataris; A. Goldschmidt; H. Gómez; J. J. Gómez-Cadenas; K. González; D. González-Díaz; R. M. Gutiérrez; J. Hauptman; J. A. Hernando Morata; D. C. Herrera; V. Herrero; F. J. Iguaz; I. G. Irastorza; V. Kalinnikov; D. Kiang; L. Labarga; I. Liubarsky; J. A. M. Lopes; D. Lorca; M. Losada; G. Luzón; A. Marí; J. Martín-Albo; A. Martínez; T. Miller; A. Moiseenko; F. Monrabal; C. M. B. Monteiro; J. M. Monzó; F. J. Mora; L. M. Moutinho; J. Muñoz Vidal; H. Natal da Luz; G. Navarro; M. Nebot; D. Nygren; C. A. B. Oliveira; R. Palma; J. Pérez; J. L. Pérez Aparicio; J. Renner; L. Ripoll; A. Rodríguez; J. Rodríguez; F. P. Santos; J. M. F. dos Santos; L. Segui; L. Serra; D. Shuman; C. Sofka; M. Sorel; J. F. Toledo; A. Tomás; J. Torrent; Z. Tsamalaidze; D. Vázquez; E. Velicheva; J. F. C. A. Veloso; J. A. Villar; R. C. Webb; T. Weber; J. White; N. Yahlali


    In this Technical Design Report (TDR) we describe the NEXT-100 detector that will search for neutrinoless double beta decay (bbonu) in Xe-136 at the Laboratorio Subterraneo de Canfranc (LSC), in Spain. The document formalizes the design presented in our Conceptual Design Report (CDR): an electroluminescence time projection chamber, with separate readout planes for calorimetry and tracking, located, respectively, behind cathode and anode. The detector is designed to hold a maximum of about 150 kg of xenon at 15 bar, or 100 kg at 10 bar. This option builds in the capability to increase the total isotope mass by 50% while keeping the operating pressure at a manageable level. The readout plane performing the energy measurement is composed of Hamamatsu R11410-10 photomultipliers, specially designed for operation in low-background, xenon-based detectors. Each individual PMT will be isolated from the gas by an individual, pressure resistant enclosure and will be coupled to the sensitive volume through a sapphire window. The tracking plane consists in an array of Hamamatsu S10362-11-050P MPPCs used as tracking pixels. They will be arranged in square boards holding 64 sensors (8 times8) with a 1-cm pitch. The inner walls of the TPC, the sapphire windows and the boards holding the MPPCs will be coated with tetraphenyl butadiene (TPB), a wavelength shifter, to improve the light collection.

  1. Leak before break evaluation for main steam piping system made of SA106 Gr.C

    SciTech Connect (OSTI)

    Yang, Kyoung Mo; Jee, Kye Kwang; Pyo, Chang Ryul; Ra, In Sik [Korea Power Engineering Company, Seoul (Korea, Republic of)


    The basis of the leak before break (LBB) concept is to demonstrate that piping will leak significantly before a double ended guillotine break (DEGB) occurs. This is demonstrated by quantifying and evaluating the leak process and prescribing safe shutdown of the plant on the basis of the monitored leak rate. The application of LBB for power plant design has reduced plant cost while improving plant integrity. Several evaluations employing LBB analysis on system piping based on DEGB design have been completed. However, the application of LBB on main steam (MS) piping, which is LBB applicable piping, has not been performed due to several uncertainties associated with occurrence of steam hammer and dynamic strain aging (DSA). The objective of this paper is to demonstrate the applicability of the LBB design concept to main steam lines manufactured with SA106 Gr.C carbon steel. Based on the material properties, including fracture toughness and tensile properties obtained from the comprehensive material tests for base and weld metals, a parametric study was performed as described in this paper. The PICEP code was used to determine leak size crack (LSC) and the FLET code was used to perform the stability assessment of MS piping. The effects of material properties obtained from tests were evaluated to determine the LBB applicability for the MS piping. It can be shown from this parametric study that the MS piping has a high possibility of design using LBB analysis.

  2. Next Generation Print-based Manufacturing for Photovoltaics and Solid State Lighting

    SciTech Connect (OSTI)

    Sue A. Carter


    For the grand challenge of reducing our energy and carbon footprint, the development of renewable energy and energy efficient technologies offer a potential solution. Energy technologies can reduce our dependence on foreign oil as well as the energy consumed by the petroleum industry, the leading consumer of energy by a U.S. industry sector. Nonetheless, the manufacturing processes utilized to manufacture equipment for alternative energy technologies often involve energy-intensive processes. This undermines some of the advantages to moving to 'green' technologies in the first place. Our answer to the Industrial Technology Program's (ITP) Grand Challenge FOA was to develop a transformational low cost manufacturing process for plastic-based photovoltaics that will lower by over 50% both energy consumption and greenhouse emissions and offer a return-of-investment of over 20%. We demonstrated a Luminescent Solar Concentrator fabricated on a plastic acrylic substrate (i.e. no glass) that increases the power output of the PV cell by 2.2x with a 2% power efficiency as well as an LSC with a 7% power efficiency that increased the power output from the PV cells by 35%. S large area 20-inch x 60-inch building-integrated photovoltaic window was fabricated using contract manufacturing with a 4% power efficiency which improved the power output of the PV cell by over 50%. In addition, accelerated lifetimes of the luminescent material demonstrate lifetimes of 20-years.

  3. Development of the Low Swirl Injector for Fuel-Flexible GasTurbines

    SciTech Connect (OSTI)

    Littlejohn, D.; Cheng, R.K.; Nazeer,W.A.; Smith, K.O


    Industrial gas turbines are primarily fueled with natural gas. However, changes in fuel cost and availability, and a desire to control carbon dioxide emissions, are creating pressure to utilize other fuels. There is an increased interest in the use of fuels from coal gasification, such as syngas and hydrogen, and renewable fuels, such as biogas and biodiesel. Current turbine fuel injectors have had years of development to optimize their performance with natural gas. The new fuels appearing on the horizon can have combustion properties that differ substantially from natural gas. Factors such as turbulent flame speed, heat content, autoignition characteristics, and range of flammability must be considered when evaluating injector performance. The low swirl injector utilizes a unique flame stabilization mechanism and is under development for gas turbine applications. Its design and mode of operation allow it to operate effectively over a wide range of conditions. Studies conducted at LBNL indicate that the LSI can operate on fuels with a wide range of flame speeds, including hydrogen. It can also utilize low heat content fuels, such as biogas and syngas. We will discuss the low swirl injector operating parameters, and how the LSC performs with various alternative fuels.

  4. A Re-Examination of the Origins of the Peculiar Velocity Field Within the Local Supercluster

    E-Print Network [OSTI]

    David Burstein


    The recent re-evaulation of the peculiar velocity field outside the Local Supercluster (Dekel et al. 1999, ApJ 522) has permitted a re-examination of the origins of the peculiar velocity field within the Local Supercluster using the Mark III Catalog of Galaxy Peculiar Velocities for spiral galaxies. It is shown that the large-scale coherent pattern of peculiar velocities within the LSC are well-fit by a combination of the Outside-Region-(generated)-Motions (O-R-M) from the Potent model with a Virgocentric infall pattern that produces 220 km/s of Virgocentric infall at the Local Group (LG) towards the Virgo cluster moving at 88 km/s towards the LG. The part of the Cosmic Microwave Background motion of the LG this model cannot fit is that perpendicular to the Supergalactic plane (the SGZ direction). On what size scale the remaing 270 km/s CMB SGZ motion of the LG is shared by neighboring galaxies cannot be determined from the present data set, but may be found if we can accurately measure galaxy distances close to the Galactic plane.

  5. Low Background Micromegas in CAST

    E-Print Network [OSTI]

    J. G. Garza; S. Aune; D. Calvet; J. F. Castel; F. E. Christensen; T. Dafni; M. Davenport; T. Decker; E. Ferrer-Ribas; J. Galán; J. A. García; I. Giomataris; R. M. Hill; F. J. Iguaz; I. G. Irastorza; A. C. Jakobsen; D. Jourde; H. Mirallas; I. Ortega; T. Papaevangelou; M. J. Pivovaroff; J. Ruz; A. Tomás; T. Vafeiadis; J. K. Vogel


    Solar axions could be converted into x-rays inside the strong magnetic field of an axion helioscope, triggering the detection of this elusive particle. Low background x-ray detectors are an essential component for the sensitivity of these searches. We report on the latest developments of the Micromegas detectors for the CERN Axion Solar Telescope (CAST), including technological pathfinder activities for the future International Axion Observatory (IAXO). The use of low background techniques and the application of discrimination algorithms based on the high granularity of the readout have led to background levels below 10$^{-6}$ counts/keV/cm$^2$/s, more than a factor 100 lower than the first generation of Micromegas detectors. The best levels achieved at the Canfranc Underground Laboratory (LSC) are as low as 10$^{-7}$ counts/keV/cm$^2$/s, showing good prospects for the application of this technology in IAXO. The current background model, based on underground and surface measurements, is presented, as well as the strategies to further reduce the background level. Finally, we will describe the R&D paths to achieve sub-keV energy thresholds, which could broaden the physics case of axion helioscopes.

  6. To appear in IEEE Trans. on Computer-Aided Design of Integrated Circuits and Systems Min-Cut Floorplacement

    E-Print Network [OSTI]

    Markov, Igor

    determined manually. Moreover, this step is generally performed only once and separate from cell placement, which includes cell placement, floorplanning, mixed-size placement and achieving routability. At every step of min-cut placement, either partitioning or wirelength- driven, fixed-outline floorplanning

  7. Oxygen Transport Ceramic Membranes

    SciTech Connect (OSTI)

    S. Bandopadhyay; N. Nagabhushana


    In the present quarter, experiments are presented on ceramic/metal interactions of Zirconia/ Ni-B-Si system and with a thin Ti coating deposited on zirconia surface. Existing facilities were modified for evaluation of environmental assisted slow crack growth and creep in flexural mode. Processing of perovskites of LSC, LSF and LSCF composition were continued for evaluation of mechanical properties as a function of environment. These studies in parallel to those on the LSFCO composition is expect to yield important information on questions such as the role of cation segregation and the stability of the perovskite structure on crack initiation vs. crack growth. Studies have been continued on the La{sub 1-x}Sr{sub x}FeO{sub 3-d} composition using neutron diffraction and TGA studies. A transition from p-type to n-type of conductor was observed at relative low pO{sub 2}, at which the majority carriers changed from the holes to electrons because of the valence state decreases in Fe due to the further loss of oxygen. Investigation on the thermodynamic properties of the membrane materials are continued to develop a complete model for the membrane transport. Data obtained at 850 C show that the stoichiometry in La{sub 0.2}Sr{sub 0.8}Fe{sub 0.8}Cr{sub 0.2}O{sub 3-x} vary from {approx}2.85 to 2.6 over the pressure range studied. From the stoichiometry a lower limit of 2.6 corresponding to the reduction of all Fe{sup 4+} to Fe{sup 3+} and no reduction of Cr{sup 3+} is expected.

  8. The development of potassium tantalate niobate thin films for satellite-based pyroelectric detectors

    SciTech Connect (OSTI)

    Cherry, H B.B. [Univ. of California, Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering


    Potassium tantalate niobate (KTN) pyroelectric detectors are expected to provide detectivities, of 3.7 x 10{sup 11} cmHz {sup {1/2}}W{sup {minus}1} for satellite-based infrared detection at 90 K. The background limited detectivity for a room-temperature thermal detector is 1.8 x 10{sup 10} cmHz{sup {1/2}}W{sup {minus}1}. KTN is a unique ferroelectric for this application because of the ability to tailor the temperature of its pyroelectric response by adjusting its ratio of tantalum to niobium. The ability to fabricate high quality KTN thin films on Si-based substrates is crucial to the development of KTN pyroelectric detectors. Si{sub x}N{sub y} membranes created on the Si substrate will provide the weak thermal link necessary to reach background limited detectivities. The device dimensions obtainable by thin film processing are expected to increase the ferroelectric response by 20 times over bulk fabricated KTN detectors. In addition, microfabrication techniques allow for easier array development. This is the first reported attempt at growth of KTN films on Si-based substrates. Pure phase perovskite films were grown by pulsed laser deposition on SrRuO{sub 3}/Pt/Ti/Si{sub x}N{sub y}/Si and SrRuO{sub 3}/Si{sub x}N{sub y}/Si structures; room temperature dielectric permittivities for the KTN films were 290 and 2.5, respectively. The dielectric permittivity for bulk grown, single crystal KTN is {approximately}380. In addition to depressed dielectric permittivities, no ferroelectric hysteresis was found between 80 and 300 K for either structure. RBS, AES, TEM and multi-frequency dielectric measurements were used to investigate the origin of this apparent lack of ferroelectricity. Other issues addressed by this dissertation include: the role of oxygen and target density during pulsed laser deposition of KTN thin films; the use of YBCO, LSC and Pt as direct contact bottom electrodes to the KTN films, and the adhesion of the bottom electrode layers to Si{sub x}N{sub y}/Si.

  9. Critical Causes of Degradation in Integrated Laboratory Scale Cells during High Temperature Electrolysis

    SciTech Connect (OSTI)

    M.S. Sohal; J.E. O'Brien; C.M. Stoots; J. J. Hartvigsen; D. Larsen; S. Elangovan; J.S. Herring; J.D. Carter; V.I. Sharma; B. Yildiz


    An ongoing project at Idaho National Laboratory involves generating hydrogen from steam using solid oxide electrolysis cells (SOEC). This report describes background information about SOECs, the Integrated Laboratory Scale (ILS) testing of solid-oxide electrolysis stacks, ILS performance degradation, and post-test examination of SOECs by various researchers. The ILS test was a 720- cell, three-module test comprised of 12 stacks of 60 cells each. A peak H2 production rate of 5.7 Nm3/hr was achieved. Initially, the module area-specific resistance ranged from 1.25 Ocm2 to just over 2 Ocm2. Total H2 production rate decreased from 5.7 Nm3/hr to a steady state value of 0.7 Nm3/hr. The decrease was primarily due to cell degradation. Post test examination by Ceramatec showed that the hydrogen electrode appeared to be in good condition. The oxygen evolution electrode does show delamination in operation and an apparent foreign layer deposited at the electrolyte interface. Post test examination by Argonne National Laboratory showed that the O2-electrode delaminated from the electrolyte near the edge. One possible reason for this delamination is excessive pressure buildup with high O2 flow in the over-sintered region. According to post test examination at the Massachusetts Institute of Technology, the electrochemical reactions have been recognized as one of the prevalent causes of their degradation. Specifically, two important degradation mechanisms were examined: (1) transport of Crcontaining species from steel interconnects into the oxygen electrode and LSC bond layers in SOECs, and (2) cation segregation and phase separation in the bond layer. INL conducted a workshop October 27, 2008 to discuss possible causes of degradation in a SOEC stack. Generally, it was agreed that the following are major degradation issues relating to SOECs: • Delamination of the O2-electrode and bond layer on the steam/O2-electrode side • Contaminants (Ni, Cr, Si, etc.) on reaction sites (triple phase boundary) • Loss of electrical/ionic conductivity of electrolyte.

  10. Epoch 3.2.2: Experiences of a First-Time User

    E-Print Network [OSTI]

    Haynal, Steve

    Out Select Hold #12;Compressor Power Rail Problems l Custom more compact arrangement of DP led Diagram l Floorplanning l Compression l Algorithm l Why This Compression? l Datapath l Power Rail Problems #12;Rogue Chip Block Diagram IN FIFO OUT FIFO TEST COMPRESSOR MID FIFO & SWITCHING DES 10 10 10 10

  11. Demo Abstract: A Cooja-based Tool for Maintaining Sensor Network Coverage Requirements in a Building

    E-Print Network [OSTI]

    Sreenan, Cormac J.

    Wireless Sensor Network (WSN) simulator, but it lacks support for modelling sens- ing coverage. We introduce WSN-Maintain, a Cooja-based tool for maintaining coverage requirements in an in-building WSN. To analyse the coverage of a building, WSN-Maintain takes as input the floorplan of the building

  12. Generating Circuit Current Constraints to Guarantee Power Grid Safety

    E-Print Network [OSTI]

    Najm, Farid N.

    Generating Circuit Current Constraints to Guarantee Power Grid Safety Zahi Moudallal ECE Dept, as well as power grid-aware placement and floorplanning. We give a rigorous problem definition and develop of power grids is a necessity in modern chip design. We will use the term "power grid" to refer to either

  13. Studying Thermal Management for Graphics-Processor Architectures Jeremy W. Sheaffer, Kevin Skadron, David P. Luebke

    E-Print Network [OSTI]

    Huang, Wei

    with the need for energy and thermal effi- ciency, creates a rich design space well-suited for studyStudying Thermal Management for Graphics-Processor Architectures Jeremy W. Sheaffer, Kevin Skadron workloads enables significant thermal gains on chips designed employing static floorplan repartitioning. 1

  14. Quantum Dynamical Behaviour in Complex Systems - A Semiclassical Approach

    SciTech Connect (OSTI)

    Gliebe, Cheryn E; Ananth, Nandini


    One of the biggest challenges in Chemical Dynamics is describing the behavior of complex systems accurately. Classical MD simulations have evolved to a point where calculations involving thousands of atoms are routinely carried out. Capturing coherence, tunneling and other such quantum effects for these systems, however, has proven considerably harder. Semiclassical methods such as the Initial Value Representation (SC-IVR) provide a practical way to include quantum effects while still utilizing only classical trajectory information. For smaller systems, this method has been proven to be most effective, encouraging the hope that it can be extended to deal with a large number of degrees of freedom. Several variations upon the original idea of the SCIVR have been developed to help make these larger calculations more tractable; these range from the simplest, classical limit form, the Linearized IVR (LSC-IVR) to the quantum limit form, the Exact Forward-Backward version (EFB-IVR). In this thesis a method to tune between these limits is described which allows us to choose exactly which degrees of freedom we wish to treat in a more quantum mechanical fashion and to what extent. This formulation is called the Tuning IVR (TIVR). We further describe methodology being developed to evaluate the prefactor term that appears in the IVR formalism. The regular prefactor is composed of the Monodromy matrices (jacobians of the transformation from initial to finial coordinates and momenta) which are time evolved using the Hessian. Standard MD simulations require the potential surfaces and their gradients, but very rarely is there any information on the second derivative. We would like to be able to carry out the SC-IVR calculation without this information too. With this in mind a finite difference scheme to obtain the Hessian on-the-fly is proposed. Wealso apply the IVR formalism to a few problems of current interest. A method to obtain energy eigenvalues accurately for complex systems is described. We proposed the use of a semiclassical correction term to a preliminary quantum calculation using, for instance, a variational approach. This allows us to increase the accuracy significantly. Modeling Nonadiabatic dynamics has always been a challenge to classical simulations because the multi-state nature of the dynamics cannot be described accurately by the time evolution on a single average surface, as is the classical approach. We show that using the Meyer-Miller-Stock-Thoss (MMST) representation of the exact vibronic Hamiltonian in combination with the IVR allows us to accurately describe dynamics where the non Born-Oppenheimer regime. One final problem that we address is that of extending this method to the long time regime. We propose the use of a time independent sampling function in the Monte Carlo integration over the phase space of initial trajectory conditions. This allows us to better choose the regions of importance at the various points in time; by using more trajectories in the important regions, we show that the integration can be converged much easier. An algorithm based loosely on the methods of Diffusion Monte Carlo is developed that allows us to carry out this time dependent sampling in a most efficient manner.


    SciTech Connect (OSTI)

    Professor Anil V. Virkar


    This report summarizes the work done during the entire project period, between October 1, 1999 and March 31, 2003, which includes a six-month no-cost extension. During the project, eight research papers have, either been, published, accepted for publication, or submitted for publication. In addition, several presentations have been made in technical meetings and workshops. The project also has provided support for four graduate students working towards advanced degrees. The principal technical objective of the project was to analyze the role of electrode microstructure on solid oxide fuel cell performance. Prior theoretical work conducted in our laboratory demonstrated that the particle size of composite electrodes has a profound effect on cell performance; the finer the particle size, the lower the activation polarization, the better the performance. The composite cathodes examined consisted of electronically conducting perovskites such as Sr-doped LaMnO{sub 3} (LSM) or Sr-doped LaCoO{sub 3} (LSC), which is also a mixed conductor, as the electrocatalyst, and yttria-stabilized zirconia (YSZ) or rare earth oxide doped CeO{sub 2} as the ionic conductor. The composite anodes examined were mixtures of Ni and YSZ. A procedure was developed for the synthesis of nanosize YSZ by molecular decomposition, in which unwanted species were removed by leaching, leaving behind nanosize YSZ. Anode-supported cells were made using the as-synthesized powders, or using commercially acquired powders. The electrolyte was usually a thin ({approx}10 microns), dense layer of YSZ, supported on a thick ({approx}1 mm), porous Ni + YSZ anode. The cathode was a porous mixture of electrocatalyst and an ionic conductor. Most of the cell testing was done at 800 C with hydrogen as fuel and air as the oxidant. Maximum power densities as high as 1.8 W/cm{sup 2} were demonstrated. Polarization behavior of the cells was theoretically analyzed. A limited amount of cell testing was done using liquid hydrocarbon fuels where reforming was achieved internally. Significant polarization losses also occur at the anode, especially at high fuel utilizations. An analysis of polarization losses requires that various contributions are isolated, and their dependence on pertinent parameters is quantitatively described. An investigation of fuel composition on gas transport through porous anodes was investigated and the role of fuel diluents was explored. This work showed that the molecular weight of the diluent has a significant effect on anode concentration polarization. This further showed that the presence of some molecular hydrogen is necessary to minimize polarization losses. Theoretical analysis has shown that the electrode microstructure has a profound effect on cell performance. In a series of experiments, cathode microstructural parameters were varied, without altering other parameters. Cathode microstructural parameters, especially three phase boundary (TPB) length, were estimated using techniques in quantitative stereology. Cell performance was quantitatively correlated with the relevant microstructural parameters, and charge transfer resistivity was explicitly evaluated. This is the first time that a fundamental parameter, which governs the activation polarization, has been quantitatively determined. An important parameter, which governs the cathodic activation polarization, and thus cell performance, is the ionic conductivity of the composite cathode. The traditional composite cathode is a mixture of LSM and YSZ. It is well known that Sr and Mg-doped LaGaO{sub 3} (LSGM), exhibits higher oxygen ion conductivity compared to YSZ. Cells were fabricated with composite cathodes comprising a mixture of LSM and LSGM. Studies demonstrated that LSGM-based composite cathodes exhibit excellent behavior. Studies have shown that Ni + YSZ is an excellent anode. In fact, in most cells, the principal polarization losses, at least at low fuel utilizations, are associated with the cathode. Theoretical analysis conducted in our group has also shown that anode-supported cells exhibi

  16. Argonne Physics Division - ATLAS

    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:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article) |govInstrumentsmfrirt DocumentationSitesWeather Outreach HomeDeKalbAnnual SiteKevin Ott10 ArgonneDear Friend,Floorplan ATLAS

  17. Argonne Physics Division - ATLAS

    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:1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:5 TablesExports(Journal Article) |govInstrumentsmfrirt DocumentationSitesWeather Outreach HomeDeKalbAnnual SiteKevin Ott10 ArgonneDear Friend,Floorplan

  18. Architectural considerations in the design of a superconducting quantum annealing processor

    E-Print Network [OSTI]

    P. I. Bunyk; E. Hoskinson; M. W. Johnson; E. Tolkacheva; F. Altomare; A. J. Berkley; R. Harris; J. P. Hilton; T. Lanting; J. Whittaker


    We have developed a quantum annealing processor, based on an array of tunably coupled rf-SQUID flux qubits, fabricated in a superconducting integrated circuit process [1]. Implementing this type of processor at a scale of 512 qubits and 1472 programmable inter-qubit couplers and operating at ~ 20 mK has required attention to a number of considerations that one may ignore at the smaller scale of a few dozen or so devices. Here we discuss some of these considerations, and the delicate balance necessary for the construction of a practical processor that respects the demanding physical requirements imposed by a quantum algorithm. In particular we will review some of the design trade-offs at play in the floor-planning of the physical layout, driven by the desire to have an algorithmically useful set of inter-qubit couplers, and the simultaneous need to embed programmable control circuitry into the processor fabric. In this context we have developed a new ultra-low power embedded superconducting digital-to-analog flux converters (DACs) used to program the processor with zero static power dissipation, optimized to achieve maximum flux storage density per unit area. The 512 single-stage, 3520 two-stage, and 512 three-stage flux-DACs are controlled with an XYZ addressing scheme requiring 56 wires. Our estimate of on-chip dissipated energy for worst-case reprogramming of the whole processor is ~ 65 fJ. Several chips based on this architecture have been fabricated and operated successfully at our facility, as well as two outside facilities (see for example [2]).