Sample records for highly insulating glazing

  1. Thermal insulated glazing unit

    SciTech Connect (OSTI)

    Selkowitz, Stephen E. (Piedmont, CA); Arasteh, Dariush K. (Oakland, CA); Hartmann, John L. (Seattle, WA)

    1991-01-01T23:59:59.000Z

    An improved insulated glazing unit is provided which can attain about R5 to about R10 thermal performance at the center of the glass while having dimensions about the same as those of a conventional double glazed insulated glazing unit. An outer glazing and inner glazing are sealed to a spacer to form a gas impermeable space. One or more rigid, non-structural glazings are attached to the inside of the spacer to divide the space between the inner and outer glazings to provide insulating gaps between glazings of from about 0.20 inches to about 0.40 inches. One or more glazing surfaces facing each thermal gap are coated with a low emissivity coating. Finally, the thermal gaps are filled with a low conductance gas such as krypton gas.

  2. Thermal insulated glazing unit

    SciTech Connect (OSTI)

    Selkowitz, S.E.; Arasteh, D.K.; Hartmann, J.L.

    1988-04-05T23:59:59.000Z

    An improved insulated glazing unit is provided which can attain about R5 to about R10 thermal performance at the center of the glass while having dimensions about the same as those of a conventional double glazed insulated glazing unit. An outer glazing and inner glazing are sealed to a spacer to form a gas impermeable space. One or more rigid, non-structural glazings are attached to the inside of the spacer to divide the space between the inner and outer glazings to provide insulating gaps between glazings of from about 0.20 inches to about 0.40 inches. One or more glazing surfaces facing each thermal gap are coated with a low emissivity coating. Finally, the thermal gaps are filled with a low conductance gas such as krypton gas. 2 figs.

  3. Highly Insulating Glazing Systems using Non-Structural Center Glazing Layers

    SciTech Connect (OSTI)

    Kohler, Christian; Arasteh, Dariush; Goudey, Howdy; Kohler, Christian

    2008-04-09T23:59:59.000Z

    Three layer insulating glass units with two low-e coatings and an effective gas fill are known to be highly insulating, with center-of-glass U-factors as low as 0.57 W/m{sup 2}-K (0.10 Btu/h-ft{sup 2}- F). Such units have historically been built with center layers of glass or plastic which extend all the way through the spacer system. This paper shows that triple glazing systems with non-structural center layers which do not create a hermetic seal at the edge have the potential to be as thermally efficient as standard designs, while potentially removing some of the production and product integration issues that have discouraged the use of triples.

  4. Long term experience with semi-conductive glaze high voltage post insulators

    SciTech Connect (OSTI)

    Baker, A.C.; Maney, J.W.; Szilagyi, Z. (Lapp Insulator Co., LeRoy, NY (US))

    1990-01-01T23:59:59.000Z

    Insulators using semi-conductive glaze have long been known for their superior contamination performance. Early glazes for this type however were not stable and successful use of semi-conductive glazed porcelain insulators was delayed many years until tin-antimony oxide glazes were developed. Service experience of eighteen years is now available for line and station post insulators with this type of glaze. Based on this experience, the aging characteristics of tin-antimony oxide semi-conductive glazes are described and quantified. Several different applications of these insulators are also described.

  5. Highly Insulating Glazing Systems using Non-Structural Center Glazing Dariush Arasteh, Howdy Goudey, and Christian Kohler

    E-Print Network [OSTI]

    units with two low-e coatings and an effective gas fill are known to be highly insulating, with center technological routes have emerged: - Aerogel is a micro-porous insulating material currently under R&D worldwide

  6. Flexible edge seal for vacuum insulating glazing units

    DOE Patents [OSTI]

    Bettger, Kenneth J.; Stark, David H.

    2012-12-11T23:59:59.000Z

    A flexible edge seal is provided for a vacuum insulating glazing unit having a first glass pane and a second glass pane spaced-apart from the first. The edge seal comprises a seal member formed of a hermetically bondable material and having a first end, a second end and a center section disposed therebetween. The first end is hermetically bondable to a first glass pane. The second end is hermetically bondable to a second glass pane. The center section comprises a plurality of convolutes.

  7. Energy Performance and Comfort Level in High Rise and Highly Glazed Office Buildings

    E-Print Network [OSTI]

    Bayraktar, M.; Perino, M.; Yilmaz, A. Z.

    2010-01-01T23:59:59.000Z

    Thermal and visual comfort in buildings play a significant role on occupants' performance but on the other hand achieving energy savings and high comfort levels can be a quite difficult task especially in high rise buildings with highly glazed...

  8. Highly Insulating Glazing Systems using Non-Structural Center Glazing Layers

    E-Print Network [OSTI]

    Arasteh, Dariush

    2008-01-01T23:59:59.000Z

    low as 0.57 W/m 2 -K (0.10 Btu/h-ft 2 -°F). Such units havevalues Btu/h-ft 2 -°F), windows relatedA 0.57 W/m 2 -K (0.10 Btu/h-ft 2 -°F) window is targeted as

  9. Spectrally selective glazings

    SciTech Connect (OSTI)

    NONE

    1998-08-01T23:59:59.000Z

    Spectrally selective glazing is window glass that permits some portions of the solar spectrum to enter a building while blocking others. This high-performance glazing admits as much daylight as possible while preventing transmission of as much solar heat as possible. By controlling solar heat gains in summer, preventing loss of interior heat in winter, and allowing occupants to reduce electric lighting use by making maximum use of daylight, spectrally selective glazing significantly reduces building energy consumption and peak demand. Because new spectrally selective glazings can have a virtually clear appearance, they admit more daylight and permit much brighter, more open views to the outside while still providing the solar control of the dark, reflective energy-efficient glass of the past. This Federal Technology Alert provides detailed information and procedures for Federal energy managers to consider spectrally selective glazings. The principle of spectrally selective glazings is explained. Benefits related to energy efficiency and other architectural criteria are delineated. Guidelines are provided for appropriate application of spectrally selective glazing, and step-by-step instructions are given for estimating energy savings. Case studies are also presented to illustrate actual costs and energy savings. Current manufacturers, technology users, and references for further reading are included for users who have questions not fully addressed here.

  10. High temperature structural insulating material

    DOE Patents [OSTI]

    Chen, W.Y.

    1984-07-27T23:59:59.000Z

    A high temperature structural insulating material useful as a liner for cylinders of high temperature engines through the favorable combination of high service temperature (above about 800/sup 0/C), low thermal conductivity (below about 0.2 W/m/sup 0/C), and high compressive strength (above about 250 psi). The insulating material is produced by selecting hollow ceramic beads with a softening temperature above about 800/sup 0/C, a diameter within the range of 20-200 ..mu..m, and a wall thickness in the range of about 2 to 4 ..mu..m; compacting the beads and a compatible silicate binder composition under pressure and sintering conditions to provide the desired structural form with the structure having a closed-cell, compact array of bonded beads.

  11. High temperature structural insulating material

    DOE Patents [OSTI]

    Chen, Wayne Y. (Munster, IN)

    1987-01-01T23:59:59.000Z

    A high temperature structural insulating material useful as a liner for cylinders of high temperature engines through the favorable combination of high service temperature (above about 800.degree. C.), low thermal conductivity (below about 0.2 W/m.degree. C.), and high compressive strength (above about 250 psi). The insulating material is produced by selecting hollow ceramic beads with a softening temperature above about 800.degree. C., a diameter within the range of 20-200 .mu.m, and a wall thickness in the range of about 2-4 .mu.m; compacting the beads and a compatible silicate binder composition under pressure and sintering conditions to provide the desired structural form with the structure having a closed-cell, compact array of bonded beads.

  12. Establishing the value of advanced glazings

    SciTech Connect (OSTI)

    Lee, E; Selkowitz, S.

    1999-01-01T23:59:59.000Z

    Numerous glazing technologies are under development worldwide to improve the performance of building facades. High-performance glazings can provide substantial energy and related environmental benefits, but often at greatly increased first cost when compared to conventional design solutions. To increase market viability, we discuss strategies to reduce the actual and owner-perceived costs associated with developing and producing advanced window systems, specifically switchable electrochromic glazings, and we also suggest marketing strategies designed to appeal to early adopter and mainstream purchasers. These strategies may be applicable to a broad range of advanced glazing materials.

  13. Highly Insulating Residential Windows Using Smart Automated Shading...

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

    Highly Insulating Residential Windows Using Smart Automated Shading Highly Insulating Residential Windows Using Smart Automated Shading Addthis 1 of 3 Residential Smart Window with...

  14. Gaseous insulators for high voltage electrical equipment

    DOE Patents [OSTI]

    Christophorou, Loucas G. (Oak Ridge, TN); James, David R. (Knoxville, TN); Pace, Marshall O. (Knoxville, TN); Pai, Robert Y. (Concord, TN)

    1981-01-01T23:59:59.000Z

    Gaseous insulators comprise compounds having high attachment cross sections for electrons having energies in the 0-1.3 electron volt range. Multi-component gaseous insulators comprise compounds and mixtures having overall high electron attachment cross sections in the 0-1.3 electron volt range and moderating gases having high cross sections for inelastic interactions with electrons of energies 1-4 electron volts. Suitable electron attachment components include hexafluorobutyne, perfluorobutene-2, perfluorocyclobutane, perfluorodimethylcyclobutane, perfluorocyclohexene, perfluoromethylcyclohexane, hexafluorobutadiene, perfluoroheptene-1 and hexafluoroazomethane. Suitable moderating gases include N.sub.2, CO, CO.sub.2 and H.sub.2. The gaseous insulating mixture can also contain SF.sub.6, perfluoropropane and perfluorobenzene.

  15. Method and apparatus for filling thermal insulating systems

    DOE Patents [OSTI]

    Arasteh, D.K.

    1992-01-14T23:59:59.000Z

    A method for filling insulated glazing units is disclosed. The method utilizes a vacuum chamber in which the insulated glazing units are placed. The insulated glazing units and vacuum chamber are evacuated simultaneously. The units are then refilled with a low conductance gas such as Krypton while the chamber is simultaneously refilled with air. 3 figs.

  16. Performance of High-Performance Glazing in IECC Compliant Building Simulation Model

    E-Print Network [OSTI]

    Mukhopadhyay, J.; Haberl, J. S.

    windows with evacuated or low-conductance gas-filled gaps (Carmody et al. 2004), and aerogel windows to reduce the heat loss (V-factor) of windows (Hartman et al. 1987). Technologies to reduce solar heat gain include improvements to existing low.../12-04, [CDROM]. College Station, TX: Energy Systems Laboratory, Texas A&M University. Hartman, J., M.Rubin, and D. Arasteh. 1987. Thermal and solar-optical properties of silica aerogel for use in insulated windows. Proceedings of the 12th - 138 ? ESL-PA-06...

  17. State-of-the-Art Highly Insulating Window Frames - Research and Market Review

    SciTech Connect (OSTI)

    Gustavsen, Arild; Jelle, Bjorn Petter; Arasteh, Dariush; Kohler, Christian

    2007-01-01T23:59:59.000Z

    This document reports the findings of a market and research review related to state-of-the-art highly insulating window frames. The market review focuses on window frames that satisfy the Passivhaus requirements (window U-value less or equal to 0.8 W/m{sup 2}K ), while other examples are also given in order to show the variety of materials and solutions that may be used for constructing window frames with a low thermal transmittance (U-value). The market search shows that several combinations of materials are used in order to obtain window frames with a low U-value. The most common insulating material seems to be Polyurethane (PUR), which is used together with most of the common structural materials such as wood, aluminum, and PVC. The frame research review also shows examples of window frames developed in order to increase the energy efficiency of the frames and the glazings which the frames are to be used together with. The authors find that two main tracks are used in searching for better solutions. The first one is to minimize the heat losses through the frame itself. The result is that conductive materials are replaced by highly thermal insulating materials and air cavities. The other option is to reduce the window frame area to a minimum, which is done by focusing on the net energy gain by the entire window (frame, spacer and glazing). Literature shows that a window with a higher U-value may give a net energy gain to a building that is higher than a window with a smaller U-value. The net energy gain is calculated by subtracting the transmission losses through the window from the solar energy passing through the windows. The net energy gain depends on frame versus glazing area, solar factor, solar irradiance, calculation period and U-value. The frame research review also discusses heat transfer modeling issues related to window frames. Thermal performance increasing measures, surface modeling, and frame cavity modeling are among the topics discussed. The review shows that the current knowledge gives the basis for improving the calculation procedures in the calculation standards. At the same time it is room for improvement within some areas, e.g. to fully understand the natural convection effects inside irregular vertical frame cavities (jambs) and ventilated frame cavities.

  18. High temperature insulation for ceramic matrix composites

    SciTech Connect (OSTI)

    Merrill, Gary B. (Monroeville, PA); Morrison, Jay Alan (Orlando, FL)

    2000-01-01T23:59:59.000Z

    A ceramic composition is provided to insulate ceramic matrix composites under high temperature, high heat flux environments. The composite comprises a plurality of hollow oxide-based spheres of varios dimentions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere. The spheres may be any combination of Mullite spheres, Alumina spheres, or stabilized Zirconia spheres. The filler powder may be any combination of Alumina, Mullite, Ceria, or Hafnia. Preferably, the phosphate binder is Aluminum Ortho-Phosphate. A method of manufacturing the ceramic insulating composition and its application to CMC substates are also provided.

  19. High temperature insulation for ceramic matrix composites

    DOE Patents [OSTI]

    Merrill, Gary B.; Morrison, Jay Alan

    2004-01-13T23:59:59.000Z

    A ceramic composition is provided to insulate ceramic matrix composites under high temperature, high heat flux environments. The composition comprises a plurality of hollow oxide-based spheres of various dimensions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere. The spheres may be any combination of Mullite spheres, Alumina spheres, or stabilized Zirconia spheres. The filler powder may be any combination of Alumina, Mullite, Ceria, or Hafnia. Preferably, the phosphate binder is Aluminum Ortho-Phosphate. A method of manufacturing the ceramic insulating composition and its application to CMC substrates are also provided.

  20. High temperature insulation for ceramic matrix composites

    SciTech Connect (OSTI)

    Merrill, Gary B. (Monroeville, PA); Morrison, Jay Alan (Orlando, FL)

    2001-01-01T23:59:59.000Z

    A ceramic composition is provided to insulate ceramic matrix composites under high temperature, high heat flux environments. The composition comprises a plurality of hollow oxide-based spheres of various dimensions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere. The spheres may be any combination of Mullite spheres, Alumina spheres, or stabilized Zirconia spheres. The filler powder may be any combination of Alumina, Mullite, Ceria, or Hafnia. Preferably, the phosphate binder is Aluminum Ortho-Phosphate. A method of manufacturing the ceramic insulating composition and its application to CMC substrates are also provided.

  1. Highly Insulating Windows Volume Purchase Program Final Report

    SciTech Connect (OSTI)

    Parker, Graham B.; Mapes, Terry S.; Zalis, WJ

    2013-02-01T23:59:59.000Z

    This report summarizes the Highly Insulating Windows Volume Purchase Program, conduced by PNNL for DOE-BTP, including a summary of outcomes and lessons learned.

  2. Issue 5: Optimizing High Levels of Insulation

    Broader source: Energy.gov [DOE]

    This presentation was given at the Summer 2012 DOE Building America meeting on July 25, 2012, and addressed the question "How much insulation is too much?"

  3. Expansion Joint Concepts for High Temperature Insulation Systems

    E-Print Network [OSTI]

    Harrison, M. R.

    1980-01-01T23:59:59.000Z

    EXPANSION JOINT CONCEPTS FOR HIGH TEMPERATURE INSULATION SYSTEMS Michael R. Harrison Johns-Manville Sales Corporation ";.,' Denver, Colorado ABSTRACT As high temperature steam and process piping expands with heat, joints beg in to open...

  4. CALCULATING OPTICAL CONSTANTS OF GLAZING MATERIALS

    E-Print Network [OSTI]

    Rubin, Michael

    2013-01-01T23:59:59.000Z

    Solar Energy CALCULATING OPTICAL CONSTANTS OF GLAZING MATERIALS Michael Rub August 1981 TWO-WEEK LOAN

  5. Integrating automated shading and smart glazings with daylight controls

    E-Print Network [OSTI]

    Selkowitz, Stephen; Lee, Eleanor

    2004-01-01T23:59:59.000Z

    Automated Shading and Smart Glazings with Daylight Controlsdaylighting, controls, smart glazing, shading, fielddeveloping switchable “smart glazings” for over a decade and

  6. Technology reviews: Glazing systems

    SciTech Connect (OSTI)

    Schuman, J.; Rubinstein, F.; Papamichael, K.; Beltran, L.; Lee, E.S.; Selkowitz, S.

    1992-09-01T23:59:59.000Z

    We present a representative review of existing, emerging, and future technology options in each of five hardware and systems areas in envelope and lighting technologies: lighting systems, glazing systems, shading systems, daylighting optical systems, and dynamic curtain wall systems. The term technology is used here to describe any design choice for energy efficiency, ranging from individual components to more complex systems to general design strategies. The purpose of this task is to characterize the state of the art in envelope and lighting technologies in order to identify those with promise for advanced integrated systems, with an emphasis on California commercial buildings. For each technology category, the following activities have been attempted to the extent possible: Identify key performance characteristics and criteria for each technology; determine the performance range of available technologies; identify the most promising technologies and promising trends in technology advances; examine market forces and market trends; and develop a continuously growing in-house database to be used throughout the project. A variety of information sources have been used in these technology characterizations, including miscellaneous periodicals, manufacturer catalogs and cut sheets, other research documents, and data from previous computer simulations. We include these different sources in order to best show the type and variety of data available, however publication here does not imply our guarantee of these data. Within each category, several broad classes are identified, and within each class we examine the generic individual technologies that fag into that class.

  7. Fabrication of high gradient insulators by stack compression

    DOE Patents [OSTI]

    Harris, John Richardson; Sanders, Dave; Hawkins, Steven Anthony; Norona, Marcelo

    2014-04-29T23:59:59.000Z

    Individual layers of a high gradient insulator (HGI) are first pre-cut to their final dimensions. The pre-cut layers are then stacked to form an assembly that is subsequently pressed into an HGI unit with the desired dimension. The individual layers are stacked, and alignment is maintained, using a sacrificial alignment tube that is removed after the stack is hot pressed. The HGI's are used as high voltage vacuum insulators in energy storage and transmission structures or devices, e.g. in particle accelerators and pulsed power systems.

  8. State-of-the-Art Highly Insulating Window Frames - Research and Market Review

    E-Print Network [OSTI]

    Gustavsen, Arild

    2008-01-01T23:59:59.000Z

    through vacuum and electrochromic vacuum glazed windows,technologies, such as an electrochromic vacuum glazedof rebate depth on an electrochromic vacuum glazed window.

  9. Dynamic measurement of heat loss coefficients through Trombe wall glazing systems

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1981-01-01T23:59:59.000Z

    A Trombe wall presents a unique opportunity to measure the heat-loss coefficient through the glazing system because the wall itself can be used as a heat meter. Since the instantaneous heat flux through the outer wall surface can be determined, the heat loss coefficient at night can be calculated by dividing by the wall surface-to-ambient temperature difference. This technique has been used to determine heat-loss coefficients for Los Alamos test rooms during the winter of 1980-1981. Glazing systems studied include single and double glazing both with and without night insulation used in conjunction with a flat black paint, and both single and double glazing used in conjunction with a selective surface.

  10. SUPERGLASS. Engineering field tests - Phase 3. Production, market planning, and product evaluation for a high-thermal-performance insulating glass design utilizing HEAT MIRROR transparent insulation. Final report

    SciTech Connect (OSTI)

    Tilford, C L

    1982-11-01T23:59:59.000Z

    HEAT MIRROR transparent window insulation consists of a clear polyester film two mils (.002'') thick with a thin, clear low-emissivity (.15) coating deposited on one side by state-of-the-art vacuum deposition processes. This neutral-colored invisible coating reflects long-wave infrared energy (heat). When mounted by being stretched with a 1/2'' air-gap on each side of the film, the resulting unit reduces heat loss by 60% compared to dual insulating glass. Southwall Corporation produces HEAT MIRROR transparent insulation and markets it to manufacturers of sealed insulating glass (I.G.) units and window and building manufacturers who make their own I.G. These companies build and sell the SUPERGLASS sealed glazing units. Units made and installed in buildings by six customers were visited. These units were located in many geographic regions, including the Pacific Northwest, Rocky Mountains, New England, Southeast, and West Coast. As much as could be obtained of their history was recorded, as was their current condition and performance. These units had been in place from two weeks to over a year. All of the units were performing thermally very well, as measured by taking temperature profiles through them and through adjacent conventional I.G. units. Some units had minor visual defects (attributed to I.G. assembly techniques) which are discussed in detail. Overall occupant acceptance was enthusiastically positive. In addition to saving energy, without compromise of optical quality or appearance, the product makes rooms with large glazing areas comfortable to be in in cold weather. All defects observed were present when built; there appears to be no in-field degradation of quality at this time.

  11. Highly Insulating Windows with a U-value less than 0.6 W/m2K

    SciTech Connect (OSTI)

    Wendell Rhine; Ying Tang; Wenting Dong; Roxana Trifu; Reduane Begag

    2008-11-30T23:59:59.000Z

    U.S. households rely primarily on three sources of energy: natural gas, electricity, and fuel oil. In the past several decades, electricity consumption by households has grown dramatically, and a significant portion of electricity used in homes is for lighting. Lighting includes both indoor and outdoor lighting and is found in virtually every household in the United States. In 2001, according to the US Energy Information Administration, lighting accounted for 101 billion kWh (8.8 percent) of U.S. household electricity use. Incandescent lamps, which are commonly found in households, are highly inefficient sources of light because about 90 percent of the energy used is lost as heat. For that reason, lighting has been one focus area to increase the efficiency of household electricity consumption. Windows have several functions, and one of the main functions is to provide a view to the outside. Daylighting is another one of windows main functions and determines the distribution of daylight to a space. Daylighting windows do not need to be transparent, and a translucent daylighting window is sufficient, and often desired, to diffuse the light and make the space more environmentally pleasing. In homes, skylights are one source of daylighting, but skylights are not very energy efficient and are inseparably linked to solar heat gain. In some climates, added solar heat gains from daylighting may be welcome; but in other climates, heat gain must be controlled. More energy efficient skylights and daylighting solutions, in general, are desired and can be designed by insulating them with aerogels. Aerogels are a highly insulating and transparent material in its pure form. The overall objective for this project was to prepare an economical, translucent, fiber-reinforced aerogel insulation material for daylighting applications that is durable for manufacturing purposes. This advanced insulation material will increase the thermal performance of daylighting windows, while satisfying constraints such as durability, cost, user acceptance, size limits, and environmental safety concerns. The energy efficient daylighting window will consist of a translucent and resilient aerogel panel sandwiched between glass panes in double glazed windows. Compared to the best windows available today, the double glazed translucent windows with 1/2-inch aerogel inserts will have a U-value of 1.2 W/m{sup 2} K (0.211 BTU/ft{sup 2} h F) without any coating or low conductivity fill gases. These windows will be more effective than the windows with an Energy Star rating of U-2 W/m{sup 2} K and could be made even more efficient by using low-e coated glass glazings and inert gas fills. This report summarizes the work accomplished on Cooperative Agreement DE-FC26-03NT41950. During this project, Aspen Aerogels made transparent and translucent aerogels from TMOS and TEOS. We characterized the transparency of the aerogels, reinforced the transparent aerogels with fibers and prepared large translucent aerogel panels and blankets. We also conducted an initial market study for energy efficient translucent windows. A lab-scale process was developed that could be scaled-up to manufacture blankets of these translucent aerogels. The large blankets prepared were used to fabricate prototype translucent windows and skylights. The primary goal of this project was to develop transparent, resilient, hydrophobic silica aerogels that have low thermal conductivities (R-10/inch) to be used to produce aerogel insulated double-glazing windows with a U value of 0.6 W/m{sup 2}K. To meet this objective we developed a process and equipment to produce blankets of translucent, hydrophobic aerogel. We focused on silica, organically-modified silica aerogels (Ormosils), and fiber reinforced silica aerogels due to the appreciable expertise in silica sol-gel processing available with the personnel at Aspen Aerogels, and also due to the quantity of knowledge available in the scientific literature. The project was conducted in three budget periods, herein called BP1, BP2 and BP3.

  12. Improved DC Gun Insulator

    SciTech Connect (OSTI)

    M.L. Neubauer, K.B. Beard, R. Sah, C. Hernandez-Garcia, G. Neil

    2009-05-01T23:59:59.000Z

    Many user facilities such as synchrotron light sources and free electron lasers require accelerating structures that support electric fields of 10-100 MV/m, especially at the start of the accelerator chain where ceramic insulators are used for very high gradient DC guns. These insulators are difficult to manufacture, require long commissioning times, and have poor reliability, in part because energetic electrons bury themselves in the ceramic, creating a buildup of charge and causing eventual puncture. A novel ceramic manufacturing process is proposed. It will incorporate bulk resistivity in the region where it is needed to bleed off accumulated charge caused by highly energetic electrons. This process will be optimized to provide an appropriate gradient in bulk resistivity from the vacuum side to the air side of the HV standoff ceramic cylinder. A computer model will be used to determine the optimum cylinder dimensions and required resistivity gradient for an example RF gun application. A ceramic material example with resistivity gradient appropriate for use as a DC gun insulator will be fabricated by glazing using doping compounds and tested.

  13. Chapter 19. High Voltage Insulation, Diagnostics and Energetic Electron and Photon Beam Interactions

    E-Print Network [OSTI]

    Chapter 19. High Voltage Insulation, Diagnostics and Energetic Electron and Photon Beam Interactions 19-1 High Voltage Insulation, Diagnostics and Energetic Electron and Photon Beam Interactions 1. DC Properties of Modern Filled Epoxy Insulation Academic and Research Staff Dr. Chathan Cooke Sponsor

  14. Evaluation of Insulation Systems for the Optimal Design of High Voltage Pulse Transformers

    E-Print Network [OSTI]

    Sylvain, Candolfi; Davide, Aguglia; Philippe, Viarouge; Jürgen, Biela; Jerome, Cros

    2015-01-01T23:59:59.000Z

    This paper presents a study for the design of the insulation systems of high voltage pulse transformer based on experimental tests and numerical simulations. Data of high voltage tests on solid and liquid insulation materials are presented and discussed. The understanding of each part of the insulation is supported by electrostatic fields simulations.

  15. High Reliability R-10 Windows Using Vacuum Insulating Glass Units

    SciTech Connect (OSTI)

    Stark, David

    2012-08-16T23:59:59.000Z

    The objective of this effort was for EverSealed Windows (“EverSealed” or “ESW”) to design, assemble, thermally and environmentally test and demonstrate a Vacuum Insulating Glass Unit (“VIGU” or “VIG”) that would enable a whole window to meet or exceed the an R-10 insulating value (U-factor ? 0.1). To produce a VIGU that could withstand any North American environment, ESW believed it needed to design, produce and use a flexible edge seal system. This is because a rigid edge seal, used by all other know VIG producers and developers, limits the size and/or thermal environment of the VIG to where the unit is not practical for typical IG sizes and cannot withstand severe outdoor environments. The rigid-sealed VIG’s use would be limited to mild climates where it would not have a reasonable economic payback when compared to traditional double-pane or triple-pane IGs. ESW’s goals, in addition to achieving a sufficiently high R-value to enable a whole window to achieve R-10, included creating a VIG design that could be produced for a cost equal to or lower than a traditional triple-pane IG (low-e, argon filled). ESW achieved these goals. EverSealed produced, tested and demonstrated a flexible edge-seal VIG that had an R-13 insulating value and the edge-seal system durability to operate reliably for at least 40 years in the harshest climates of North America.

  16. Glazing materials for solar and architectural applications. Final report

    SciTech Connect (OSTI)

    Lampert, C.M. [ed.

    1994-09-01T23:59:59.000Z

    This report summarizes five collaborative research projects on glazings performed by participants in Subtask C of IEA Solar Heating and Cooling Programme (SHC) Task 10, Materials Research and Testing. The projects include materials characterization, optical and thermal measurements, and durability testing of several types of new glazings Three studies were completed on electrochromic and dispersed liquid crystals for smart windows, and two were completed for low-E coatings and transparent insulation materials for more conventional window and wall applications. In the area of optical switching materials for smart windows, the group developed more uniform characterization parameters that are useful to determine lifetime and performance of electrochromics. The detailed optical properties of an Asahi (Japan) prototype electrochromic window were measured in several laboratories. A one square meter array of prototype devices was tested outdoors and demonstrated significant cooling savings compared to tinted static glazing. Three dispersed liquid crystal window devices from Taliq (USA) were evaluated. In the off state, these liquid crystal windows scatter light greatly. When a voltage of about 100 V ac is applied, these windows become transparent. Undyed devices reduce total visible light transmittance by only .25 when switched, but this can be increased to .50 with the use of dyed liquid crystals. A wide range of solar-optical and emittance measurements were made on low-E coated glass and plastic. Samples of pyrolytic tin oxide from Ford glass (USA) and multilayer metal-dielectric coatings from Interpane (Germany) and Southwall (USA) were evaluated. In addition to optical characterization, the samples were exposure-tested in Switzerland. The thermal and optimal properties of two different types of transparent insulation materials were measured.

  17. Method for improving performance of highly stressed electrical insulating structures

    DOE Patents [OSTI]

    Wilson, Michael J. (Modesto, CA); Goerz, David A. (Brentwood, CA)

    2002-01-01T23:59:59.000Z

    Removing the electrical field from the internal volume of high-voltage structures; e.g., bushings, connectors, capacitors, and cables. The electrical field is removed from inherently weak regions of the interconnect, such as between the center conductor and the solid dielectric, and places it in the primary insulation. This is accomplished by providing a conductive surface on the inside surface of the principal solid dielectric insulator surrounding the center conductor and connects the center conductor to this conductive surface. The advantage of removing the electric fields from the weaker dielectric region to a stronger area improves reliability, increases component life and operating levels, reduces noise and losses, and allows for a smaller compact design. This electric field control approach is currently possible on many existing products at a modest cost. Several techniques are available to provide the level of electric field control needed. Choosing the optimum technique depends on material, size, and surface accessibility. The simplest deposition method uses a standard electroless plating technique, but other metalization techniques include vapor and energetic deposition, plasma spraying, conductive painting, and other controlled coating methods.

  18. Round-robin artificial contamination test on high voltage dc insulators

    SciTech Connect (OSTI)

    Naito, K.; Schneider, H.M.

    1995-07-01T23:59:59.000Z

    This paper summarizes the results of a worldwide round-robin test of high voltage dc (HVDC) insulators, which was carried out in six laboratories aiming at standardization of the method for artificial contamination tests on HVDC insulators. Flashover characteristics of three kinds of specimens were evaluated by the clean fog and the salt fog procedures. Sufficient information is now available to allow the preparation of provisional international specifications for artificial contamination testing of HVDC insulators.

  19. Measure Guideline: Three High Performance Mineral Fiber Insulation Board Retrofit Solutions

    SciTech Connect (OSTI)

    Neuhauser, K.

    2015-01-01T23:59:59.000Z

    This Measure Guideline describes a high performance enclosure retrofit package that uses mineral fiber insulation board. The Measure Guideline describes retrofit assembly and details for wood frame roof and walls and for cast concrete foundations. This Measure Guideline is intended to serve contractors and designers seeking guidance for non-foam exterior insulation retrofit.

  20. High constriction ratio continuous insulator based dielectrophoretic particle sorting

    E-Print Network [OSTI]

    Wang, Qianru, S.M. Massachusetts Institute of Technology

    2014-01-01T23:59:59.000Z

    Low frequency insulator based dielectrophoresis (iDEP) is a promising technique to study cell surface dielectric properties. To date, iDEP has been exploited to distinguish, characterize, and manipulate particles and ...

  1. High-temperature zirconia insulation and method for making same

    DOE Patents [OSTI]

    Wrenn, G.E. Jr.; Holcombe, C.E. Jr.; Lewis, J. Jr.

    1988-05-10T23:59:59.000Z

    The present invention is directed to a highly pure, partially stabilized, fibrous zirconia composite for use as thermal insulation in environments where temperatures up to about 2,000 C are utilized. The composite of the present invention is fabricated into any suitable configuration such as a cone, cylinder, dome or the like by vacuum molding an aqueous slurry of partially stabilized zirconia fibers into a desired configuration on a suitably shaped mandrel. The molded fibers are infiltrated with zirconyl nitrate and the resulting structure is then dried to form a rigid structure which may be removed and placed in a furnace. The structure is then heated in air to a temperature of about 600 C for driving off the nitrate from the structure and for oxidizing the zirconyl ion to zirconia. Thereafter, the structure is heated to about 950 to 1,250 C to fuse the zirconia fibers at their nexi in a matrix of zirconia. The composite produced by the present invention is self-supporting and can be readily machined to desired final dimensions. Additional heating to about 1,800 to 2,000 C further improves structural rigidity.

  2. Fabricate-on-Demand Vacuum Insulating Glazings | Department of Energy

    Office of Environmental Management (EM)

    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),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelinesProvedDecember 2005DepartmentDecember U.S. Department-5 METRIC SUMMARY FY 2015

  3. Fabricate-on-Demand Vacuum Insulating Glazings | Department of Energy

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

    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 Delicious Rank EERE:YearRound-UpHeat PumpRecord ofESPCofConstructionofFY 2011 Report toAnnuAl Progress rePort2

  4. Movable insulation. A guide to reducing heating and cooling losses through the windows in your home

    SciTech Connect (OSTI)

    Langdon, W.K.

    1980-01-01T23:59:59.000Z

    A typical house loses 25 to 30% of its heat through windows, and a house with large windows may lose as much as 50%. Numerous movable-insulation systems that will cut the heat loss through windows in half are described. Chapters are: The Energy-Responsive Dwelling, Past to Present; Window Heat Losses and Gains; Enhanced Glazing Systems; Choosing a Window-Insulation Design for Your Home; Pop-In Shutters; Thermal Curtains - Blankets that Fold; Thermal Shades - Blankets that Roll; Thermal Shutters and Folding Screens; Insulation Between Glazing and Interior Louvers; Exterior Hinged and Sliding Shutters; Sun-Shading Screens; Exterior Roll Shutters; Shutters for Skylights; Shutters for Clerestory Windows; Interior Greenhouse Insulation Systems; Exterior Insulation for Greenhouses; Movable Insulation to Assist Passive Space Heating; and Movable Insulation to Assist Solar Water Heaters. Appendices include the following: insulated shade and shutter construction; the economics of window insulation; movable insulation products, hardware, and components; further technical information; and design sources. (MCW)

  5. Integrating automated shading and smart glazings with daylight controls

    E-Print Network [OSTI]

    Selkowitz, Stephen; Lee, Eleanor

    2004-01-01T23:59:59.000Z

    Effect of Venetian Blinds on Daylight Photoelectric Controland Smart Glazings with Daylight Controls Stephen Selkowitzwith the outdoors and daylight to enhance the quality of the

  6. Side-by-Side Field Evaluation of Highly Insulating Windows in the PNNL Lab Homes

    SciTech Connect (OSTI)

    Widder, Sarah H.; Parker, Graham B.; Baechler, Michael C.; Bauman, Nathan N.

    2012-08-01T23:59:59.000Z

    To examine the energy, air leakage, and thermal performance of highly insulating windows, a field evaluation was undertaken in a matched pair of all-electric, factory-built “Lab Homes” located on the Pacific Northwest National Laboratory (PNNL) campus in Richland, Washington. The “baseline” Lab Home B was retrofitted with “standard” double-pane clear aluminum-frame slider windows and patio doors, while the “experimental” Lab Home A was retrofitted with Jeld-Wen® triple-pane vinyl-frame slider windows and patio doors with a U-factor of 0.2 and solar heat gain coefficient of 0.19. To assess the window, the building shell air leakage, energy use, and interior temperatures of each home were compared during the 2012 winter heating and summer cooling seasons. The measured energy savings in Lab Home B averaged 5,821 watt-hours per day (Wh/day) during the heating season and 6,518 Wh/day during the cooling season. The overall whole-house energy savings of Lab Home B compared to Lab Home A are 11.6% ± 1.53% for the heating season and 18.4 ± 2.06% for the cooling season for identical occupancy conditions with no window coverings deployed. Extrapolating these energy savings numbers based on typical average heating degree days and cooling degree days per year yields an estimated annual energy savings of 12.2%, or 1,784 kWh/yr. The data suggest that highly insulating windows are an effective energy-saving measure that should be considered for high-performance new homes and in existing retrofits. However, the cost effectiveness of the measure, as determined by the simple payback period, suggests that highly insulating window costs continue to make windows difficult to justify on a cost basis alone. Additional reductions in costs via improvements in manufacturing and/or market penetration that continue to drive down costs will make highly insulating windows much more viable as a cost-effective energy efficiency measure. This study also illustrates that highly insulating windows have important impacts on peak load, occupant comfort, and condensation potential, which are not captured in the energy savings calculation. More consistent and uniform interior temperature distributions suggest that highly insulated windows, as part of a high performance building envelope, may enable more centralized duct design and downsized HVAC systems. Shorter, more centralized duct systems and smaller HVAC systems to yield additional cost savings, making highly insulating windows more cost effective as part of a package of new construction or retrofit measures which achieve significant reductions in home energy use.

  7. Thermal insulation for high temperature microwave sintering operations and method thereof

    DOE Patents [OSTI]

    Holcombe, C.E.; Dykes, N.L.; Morrow, M.S.

    1995-09-12T23:59:59.000Z

    Superior microwave transparent thermal insulations for high temperature microwave sintering operations were prepared. One embodiment of the thermal insulation comprises granules of boron nitride coated with a very thin layer of glassy carbon made by preparing a glassy carbon precursor and blending it with boron nitride powder to form a mixture. The blended mixture is granulated to form a grit which is dried and heated to form the granules of boron nitride coated with a glassy carbon. Alternatively, grains of glassy carbon are coated with boron nitride by blending a mixture of a slurry comprising boron nitride, boric acid binder, and methyl alcohol with glassy carbon grains to form a blended mixture. The blended mixture is dried to form grains of glassy carbon coated with boron nitride. In addition, a physical mixture of boron nitride powder and glassy carbon grains has also been shown to be an excellent thermal insulation material for microwave processing and sintering. 1 fig.

  8. Method of preparing thermal insulation for high temperature microwave sintering operations

    DOE Patents [OSTI]

    Holcombe, C.E.; Dykes, N.L.; Morrow, M.S.

    1996-07-16T23:59:59.000Z

    Superior microwave transparent thermal insulations for high temperature microwave sintering operations were prepared. One embodiment of the thermal insulation comprises granules of boron nitride coated with a very thin layer of glassy carbon made by preparing a glassy carbon precursor and blending it with boron nitride powder to form a mixture. The blended mixture is granulated to form a grit which is dried and heated to form the granules of boron nitride coated with a glassy carbon. Alternatively, grains of glassy carbon are coated with boron nitride by blending a mixture of a slurry comprising boron nitride, boric acid binder, and methyl alcohol with glassy carbon grains to form a blended mixture. The blended mixture is dried to form grains of glassy carbon coated with boron nitride. In addition, a physical mixture of boron nitride powder and glassy carbon grains has also been shown to be an excellent thermal insulation material for microwave processing and sintering. 1 fig.

  9. Method of preparing thermal insulation for high temperature microwave sintering operations

    DOE Patents [OSTI]

    Holcombe, Cressie E. (Knoxville, TN); Dykes, Norman L. (Oak Ridge, TN); Morrow, Marvin S. (Kingston, TN)

    1996-01-01T23:59:59.000Z

    Superior microwave transparent thermal insulations for high temperature microwave sintering operations were prepared. One embodiment of the thermal insulation comprises granules of boron nitride coated with a very thin layer of glassy carbon made by preparing a glassy carbon precursor and blending it with boron nitride powder to form a mixture. The blended mixture is granulated to form a grit which is dried and heated to form the granules of boron nitride coated with a glassy carbon. Alternatively, grains of glassy carbon are coated with boron nitride by blending a mixture of a slurry comprising boron nitride, boric acid binder, and methyl alcohol with glassy carbon grains to form a blended mixture. The blended mixture is dried to form grains of glassy carbon coated with boron nitride. In addition, a physical mixture of boron nitride powder and glassy carbon grains has also been shown to be an excellent thermal insulation material for microwave processing and sintering.

  10. Thermal insulation for high temperature microwave sintering operations and method thereof

    DOE Patents [OSTI]

    Holcombe, Cressie E. (Knoxville, TN); Dykes, Norman L. (Oak Ridge, TN); Morrow, Marvin S. (Kingston, TN)

    1995-01-01T23:59:59.000Z

    Superior microwave transparent thermal insulations for high temperature microwave sintering operations were prepared. One embodiment of the thermal insulation comprises granules of boron nitride coated with a very thin layer of glassy carbon made by preparing a glassy carbon precursor and blending it with boron nitride powder to form a mixture. The blended mixture is granulated to form a grit which is dried and heated to form the granules of boron nitride coated with a glassy carbon. Alternatively, grains of glassy carbon are coated with boron nitride by blending a mixture of a slurry comprising boron nitride, boric acid binder, and methyl alcohol with glassy carbon grains to form a blended mixture. The blended mixture is dried to form grains of glassy carbon coated with boron nitride. In addition, a physical mixture of boron nitride powder and glassy carbon grains has also been shown to be an excellent thermal insulation material for microwave processing and sintering.

  11. SINTEF Building and Infrastructure State-of-the-Art Highly Insulating

    E-Print Network [OSTI]

    is that conductive materials are replaced by highly thermal insulating materials and air cavities. The other option be used for constructing window frames with a low thermal transmittance (U-value). The market search shows that several combinations of materials are used in order to obtain window frames with a low U-value. The most

  12. Durability of Polymeric Glazing and Absorber Materials

    SciTech Connect (OSTI)

    Jorgensen, G.; Terwilliger, K.; Bingham, C.; Lindquist, C.; Milbourne, M.

    2005-11-01T23:59:59.000Z

    The Solar Heating and Lighting Program has set the goal of reducing the cost of solar water heating systems by at least 50%. An attractive approach to such large cost reduction is to replace glass and metal parts with less-expensive, lighter-weight, more-integrated polymeric components. The key challenge with polymers is to maintain performance and assure requisite durability for extended lifetimes. We have begun evaluation of several new UV-screened polycarbonate sheet glazing constructions. This has involved interactions with several major polymer industry companies to obtain improved candidate samples. Proposed absorber materials were tested for UV resistance, and appear adequate for unglazed ICS absorbers.

  13. Calcium silicate insulation structure

    DOE Patents [OSTI]

    Kollie, Thomas G. (Oak Ridge, TN); Lauf, Robert J. (Oak Ridge, TN)

    1995-01-01T23:59:59.000Z

    An insulative structure including a powder-filled evacuated casing utilizes a quantity of finely divided synthetic calcium silicate having a relatively high surface area. The resultant structure-provides superior thermal insulating characteristics over a broad temperature range and is particularly well-suited as a panel for a refrigerator or freezer or the insulative barrier for a cooler or a insulated bottle.

  14. A high-speed, low-power analog-to-digital converter in fully depleted silicon-on-insulator technology

    E-Print Network [OSTI]

    Lundberg, Kent Howard

    2002-01-01T23:59:59.000Z

    This thesis demonstrates a one-volt, high-speed, ultra-low-power, six-bit flash analog-to-digital converter fabricated in a fully depleted silicon-on-insulator CMOS technology. Silicon-on-insulator CMOS technology provides ...

  15. Boson topological insulators: A window into highly entangled quantum phases

    E-Print Network [OSTI]

    Wang, Chong

    We study several aspects of the realization of global symmetries in highly entangled phases of quantum matter. Examples include gapped topological ordered phases, gapless quantum spin liquids, and non-Fermi liquid phases. ...

  16. Electronic properties of doped Mott insulators and high temperature superconductors

    E-Print Network [OSTI]

    Ribeiro, Tiago Castro

    2005-01-01T23:59:59.000Z

    High-temperature superconducting cuprates, which are the quintessential example of a strongly correlated system and the most extensively studied materials after semiconductors, spurred the development in the fields of ...

  17. "Flexible aerogel as a superior thermal insulation for high temperature superconductor cable applications"

    SciTech Connect (OSTI)

    White, Shannon O. [Aspen Aerogel, Inc.; Demko, Jonathan A [ORNL; Tomich, A. [Aspen Aerogel, Inc.

    2010-01-01T23:59:59.000Z

    High temperature superconducting (HTS) cables are an advanced technology that can both strengthen and improve the national electrical distribution infrastructure. HTS cables require sufficient cooling to overcome inherent low temperature heat loading. Heat loads are minimized by the use of cryogenic envelopes or cryostats. Cryostats require improvement in efficiency, reliability, and cost reduction to meet the demanding needs of HTS conductors (1G and 2G wires). Aspen Aerogels has developed a compression resistant aerogel thermal insulation package to replace compression sensitive multi-layer insulation (MLI), the incumbent thermal insulation, in flexible cryostats for HTS cables. Oak Ridge National Laboratory tested a prototype aerogel package in a lab-scale pipe apparatus to measure the rate of heat invasion. The lab-scale pipe test results of the aerogel solution will be presented and directly compared to MLI. A compatibility assessment of the aerogel material with HTS system components will also be presented. The aerogel thermal insulation solution presented will meet the demanding needs of HTS cables.

  18. Field Evaluation of Highly Insulating Windows in the Lab Homes: Winter Experiment

    SciTech Connect (OSTI)

    Parker, Graham B.; Widder, Sarah H.; Bauman, Nathan N.

    2012-06-01T23:59:59.000Z

    This field evaluation of highly insulating windows was undertaken in a matched pair of 'Lab Homes' located on the Pacific Northwest National Laboratory (PNNL) campus during the 2012 winter heating season. Improving the insulation and solar heat gain characteristics of a home's windows has the potential to significantly improve the home's building envelope and overall thermal performance by reducing heat loss (in the winter), and cooling loss and solar heat gain (in the summer) through the windows. A high quality installation and/or window retrofit will also minimize or reduce air leakage through the window cavity and thus also contribute to reduced heat loss in the winter and cooling loss in the summer. These improvements all contribute to decreasing overall annual home energy use. Occupant comfort (non-quantifiable) can also be increased by minimizing or eliminating the cold 'draft' (temperature) many residents experience at or near window surfaces that are at a noticeably lower temperature than the room air temperature. Lastly, although not measured in this experiment, highly insulating windows (triple-pane in this experiment) also have the potential to significantly reduce the noise transmittance through windows compared to standard double-pane windows. The metered data taken in the Lab Homes and data analysis presented here represent 70 days of data taken during the 2012 heating season. As such, the savings from highly insulating windows in the experimental home (Lab Home B) compared to the standard double-pane clear glass windows in the baseline home (Lab Home A) are only a portion of the energy savings expected from a year-long experiment that would include a cooling season. The cooling season experiment will take place in the homes in the summer of 2012, and results of that experiment will be reported in a subsequent report available to all stakeholders.

  19. Development of high performance refractory fibers with enhanced insulating properties and longer service lifetimes

    SciTech Connect (OSTI)

    Martin, P.C.; DePoorter, G.L.; Munoz, D.R.

    1991-02-01T23:59:59.000Z

    We have initiated a three phase investigation of the development of high performance refractory fibers with enhanced insulating properties and longer usable lifetimes. This report presents the results of the first phase of the study, performed from Aug. 1989 through Feb. 1991, which shows that significant energy saving are possible through the use of high temperature insulating fibers that better retain their efficient insulating properties during the service lifetime of the fibers. The remaining phases of this program include the pilot scale development and then full scale production feasibility development and evaluation of enhanced high temperature refractory insulting fibers. This first proof of principle phase of the program presents a summary of the current use patterns of refractory fibers, a laboratory evaluation of the high temperature performance characteristics of selected typical refractory fibers and an analysis of the potential energy savings through the use of enhanced refractory fibers. The current use patterns of refractory fibers span a wide range of industries and high temperature furnaces within those industries. The majority of high temperature fiber applications are in furnaces operating between 2000 and 26000{degrees}F. The fibers used in furnaces operating within this range provide attractive thermal resistance and low thermal storage at reasonable cost. A series of heat treatment studies performed for this phase of the program has shown that the refractory fibers, as initially manufactured, have attractive thermal conductivities for high temperature applications but the fibers go through rapid devitrification and subsequent crystal growth upon high temperature exposure. Development of improved fibers, maintaining the favorable characteristics of the existing as-manufactured fibers, could save between 1 and 4% of the energy consumed in high temperature furnaces using refractory fibers.

  20. Chromogenic switchable glazing: Towards the development of the smart window

    SciTech Connect (OSTI)

    Lampert, C.M.

    1995-06-01T23:59:59.000Z

    The science and technology of chromogenic materials for switchable glazings in building applications is discussed. These glazings can be used for dynamic control of solar and visible energy. Currently many researchers and engineers are involved with the development of products in this field. A summary of activities in Japan, Europe, Australia, USA and Canada is made. The activities of the International Energy Agency are included. Both non-electrically activated and electrically activated glazings are discussed. Technologies covered in the first category are photochromics, and thermochromics and thermotropics. A discussion of electrically activated chromogenic glazings includes dispersed liquid crystals, dispersed particles and electrochromics. A selection of device structures and performance characteristics are compared. A discussion of transparent conductors is presented. Technical issues concerning large-area development of smart windows are discussed.

  1. High transition temperature superconductor/insulator bilayers for the development of ultra-fast electronics

    SciTech Connect (OSTI)

    Sirena, M.; Félix, L. Avilés [Consejo Nacional de Investigaciones Científicas y Técnicas, Centro Atómico Bariloche, CNEA, Bustillo 9500, 8400 Bariloche (Argentina) [Consejo Nacional de Investigaciones Científicas y Técnicas, Centro Atómico Bariloche, CNEA, Bustillo 9500, 8400 Bariloche (Argentina); Instituto Balseiro, Universidad Nacional de Cuyo and CNEA, 8400 Bariloche (Argentina); Haberkorn, N. [Consejo Nacional de Investigaciones Científicas y Técnicas, Centro Atómico Bariloche, CNEA, Bustillo 9500, 8400 Bariloche (Argentina)] [Consejo Nacional de Investigaciones Científicas y Técnicas, Centro Atómico Bariloche, CNEA, Bustillo 9500, 8400 Bariloche (Argentina)

    2013-07-29T23:59:59.000Z

    High transition temperature superconductor (HTc)/SrTiO{sub 3} (STO) bilayers were fabricated by sputtering deposition on (100) STO substrates. Their transport and morphological properties were characterized using conductive atomic force microscopy. The STO barriers present good insulating properties, with long attenuation lengths (? ? 1 nm) which reduce the junction resistance and increase the operating critical current. The samples present roughness values smaller than 1 nm, with an extremely low density of surface defects (?5 × 10{sup ?5} defects/?m{sup 2}). The high control of the barrier quality over large defect free surfaces is encouraging for the development of microelectronics devices based in HTc Josephson junctions.

  2. Shrink Tube Insulation Apparatus for Rebco Superconducting Tapes for Use in High Field Magnets

    E-Print Network [OSTI]

    Whittington, Andrew

    An increasing number of applications require the use of high temperature superconductors (HTS) such as (RE=Rare Earth) Ba2Cu3O7-x (REBCO) coated conductors [1]. HTS conductors show particularly great potential for high field magnets applications [1] due to their high upper critical fields [2], But several groups have shown that REBCO coated conductors are prone to delamination failure [3] [4] [5]. Under relatively low transverse stress the HTS film separates from the substrate and the conductor degrades [6]. This is problematic due to high transverse stresses that occur in fully epoxy impregnated solenoids wound with this conductor. Application of thin walled heat shrink tubing introduces a weak plane around the conductor, preventing delamination degradation [7]. However, manual application of the shrink tubing is impractical, requiring three operators limited to insulating 100 m lengths or less of REBCO conductor. The high risk of damage to the conductor, also associated with this process, shows the need for...

  3. Atomic scale 0-pi transition in a high-Tc superconductor/ferromagnetic-insulator/high-T superconductor Josephson junction

    E-Print Network [OSTI]

    Kawabata, Shiro; Asano, Yasuhiro

    2011-01-01T23:59:59.000Z

    We study the Josephson transport in a high-Tc superconductor/ferromagnetic-insulator(FI)/high-Tc superconductor numerically. We found the formation of a pi-junction in such systems. More remarkably the ground state of such junction alternates between 0- and pi-states when thickness of FI is increasing by a single atomic layer. We propose an experimental setup for observing the atomic-scale 0-pi transition. Such FI-based pi-junctions can be used to implement highly-coherent quantum bits.

  4. Investigation of a high impedance magnetically insulated transmission line oscillator with hollow load

    SciTech Connect (OSTI)

    Zhou Heng; Shu Ting; Li Zhiqiang [College of Opto-electric Science and Engineering, National University of Defense Technology, Hunan 410073 (China)

    2012-09-15T23:59:59.000Z

    A novel high-impedance magnetically insulated transmission line oscillator (MILO) with greatly restrained power deposition on the anode has been investigated. Methods to increase the MILO impedance and decrease the anode current are discussed. A MILO with impedance of 30 {Omega} and power conversion efficiency of 25% is presented by particle-in-cell simulations. Compared with the previous MILO in our lab, the anode current of the proposed MILO is reduced about 50%, the power conversion efficiency doubles, and the power deposition on anode is reduced nearly one half. Furthermore, considerations for reducing the power deposition on load have also been carried out in MILO design, and the load current is reduced to 4.6 kA, only 17% of the total anode current. Finally, a hollow load was introduced to reduce the power deposition density on the load, without decreasing the power conversion efficiency.

  5. Electrical wire insulation and electromagnetic coil

    DOE Patents [OSTI]

    Bich, George J. (Penn Hills, PA); Gupta, Tapan K. (Monroeville, PA)

    1984-01-01T23:59:59.000Z

    An electromagnetic coil for high temperature and high radiation application in which glass is used to insulate the electrical wire. A process for applying the insulation to the wire is disclosed which results in improved insulation properties.

  6. Peg supported thermal insulation panel

    DOE Patents [OSTI]

    Nowobilski, Jeffert J. (Orchard Park, NY); Owens, William J. (Kenmore, NY)

    1985-01-01T23:59:59.000Z

    A thermal insulation panel which is lightweight, load bearing, accommodates thermal stress, and has excellent high temperature insulation capability comprising high performance insulation between thin metal walls supported by high density, high strength glass pegs made in compliance with specified conditions of time, temperature and pressure.

  7. Peg supported thermal insulation panel

    DOE Patents [OSTI]

    Nowobilski, J.J.; Owens, W.J.

    1985-04-30T23:59:59.000Z

    A thermal insulation panel which is lightweight, load bearing, accommodates thermal stress, and has excellent high temperature insulation capability comprises high performance insulation between thin metal walls supported by high density, high strength glass pegs made in compliance with specified conditions of time, temperature and pressure. 2 figs.

  8. Espinosa Glaze Polychrome Bowl New Mexico Cultural Assets Digital Repository

    E-Print Network [OSTI]

    Maccabe, Barney

    Espinosa Glaze Polychrome Bowl NM CADRe New Mexico Cultural Assets Digital Repository and e for Advanced Research Computing; thomas@phys.unm.edu) Led by the University of New Mexico Maxwell Museum of Anthropology (MMA), the New Mexico Cultural Assets Digital Repository and efacility is being established

  9. High voltage capability electrical coils insulated with materials containing SF.sub.6 gas

    DOE Patents [OSTI]

    Lanoue, Thomas J. (Muncie, IN); Zeise, Clarence L. (Penn Township, Allegheny County, PA); Wagenaar, Loren (Muncie, IN); Westervelt, Dean C. (Acme, PA)

    1988-01-01T23:59:59.000Z

    A coil is made having a plurality of layers of adjacent metal conductor windings subject to voltage stress, where the windings have insulation therebetween containing a small number of minute disposed throughout its cross-section, where the voids are voids filled with SF.sub.6 gas to substitute for air or other gaseous materials in from about 60% to about 95% of the cross-sectional void volume in the insulation, thus incorporating an amount of SF.sub.6 gas in the cross-section of the insulation effective to substantially increase corona inception voltages.

  10. A search model for topological insulators with high-throughput robustness descriptors

    SciTech Connect (OSTI)

    Yang, Kesong; Setyawan, Wahyu; Wang, Shidong; Nardelli, Marco B.; Curtarolo, Stephano

    2012-05-13T23:59:59.000Z

    Topological insulators (TI) are becoming one of the most studied classes of novel materials because of their great potential for applications ranging from spintronics to quantum computers. To fully integrate TI materials in electronic devices, high-quality epitaxial single-crystalline phases with sufficiently large bulk bandgaps are necessary. Current efforts have relied mostly on costly and time-consuming trial-and-error procedures. Here we show that by defining a reliable and accessible descriptor {cflx X}TI, which represents the topological robustness or feasibility of the candidate, and by searching the quantum materials repository aflowlib.org, we have automatically discovered 28 TIs (some of them already known) in five different symmetry families. These include peculiar ternary halides, Cs{l_brace}Sn,Pb,Ge{r_brace}{l_brace}Cl,Br,I{r_brace}{sub 3}, which could have been hardly anticipated without high-throughput means. Our search model, by relying on the significance of repositories in materials development, opens new avenues for the discovery of more TIs in different and unexplored classes of systems.

  11. Key Elements of and Materials Performance Targets for Highly Insulating Window Frames

    SciTech Connect (OSTI)

    Gustavsen, Arild; Grynning, Steinar; Arasteh, Dariush; Jelle, Bjorn Petter; Goudey, Howdy

    2011-03-28T23:59:59.000Z

    The thermal performance of windows is important for energy efficient buildings. Windows typically account for about 30-50 percent of the transmission losses though the building envelope, even if their area fraction of the envelope is far less. The reason for this can be found by comparing the thermal transmittance (U-factor) of windows to the U-factor of their opaque counterparts (wall, roof and floor constructions). In well insulated buildings the U-factor of walls, roofs an floors can be between 0.1-0.2 W/(m2K). The best windows have U-values of about 0.7-1.0. It is therefore obvious that the U-factor of windows needs to be reduced, even though looking at the whole energy balance for windows (i.e. solar gains minus transmission losses) makes the picture more complex.In high performance windows the frame design and material use is of utmost importance, as the frame performance is usually the limiting factor for reducing the total window U-factor further. This paper describes simulation studies analyzing the effects on frame and edge-of-glass U-factors of different surface emissivities as well as frame material and spacer conductivities. The goal of this work is to define materials research targets for window frame components that will result in better frame thermal performance than is exhibited by the best products available on the market today.

  12. Fourier analysis of conductive heat transfer for glazed roofing materials

    SciTech Connect (OSTI)

    Roslan, Nurhana Lyana; Bahaman, Nurfaradila; Almanan, Raja Noorliyana Raja; Ismail, Razidah [Faculty of Computer and Mathematical Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia); Zakaria, Nor Zaini [Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor (Malaysia)

    2014-07-10T23:59:59.000Z

    For low-rise buildings, roof is the most exposed surface to solar radiation. The main mode of heat transfer from outdoor via the roof is conduction. The rate of heat transfer and the thermal impact is dependent on the thermophysical properties of roofing materials. Thus, it is important to analyze the heat distribution for the various types of roofing materials. The objectives of this paper are to obtain the Fourier series for the conductive heat transfer for two types of glazed roofing materials, namely polycarbonate and polyfilled, and also to determine the relationship between the ambient temperature and the conductive heat transfer for these materials. Ambient and surface temperature data were collected from an empirical field investigation in the campus of Universiti Teknologi MARA Shah Alam. The roofing materials were installed on free-standing structures in natural ventilation. Since the temperature data are generally periodic, Fourier series and numerical harmonic analysis are applied. Based on the 24-point harmonic analysis, the eleventh order harmonics is found to generate an adequate Fourier series expansion for both glazed roofing materials. In addition, there exists a linear relationship between the ambient temperature and the conductive heat transfer for both glazed roofing materials. Based on the gradient of the graphs, lower heat transfer is indicated through polyfilled. Thus polyfilled would have a lower thermal impact compared to polycarbonate.

  13. Vacuum insulation of the high energy negative ion source for fusion application

    SciTech Connect (OSTI)

    Kojima, A.; Hanada, M.; Inoue, T.; Watanabe, K.; Taniguchi, M.; Kashiwagi, M.; Umeda, N.; Tobari, H. [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Hilmi, A.; Kobayashi, S.; Yamano, Y. [Saitama University, Saitama, Saitama-ken, 338-8570 (Japan); Grisham, L. R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2012-02-15T23:59:59.000Z

    Vacuum insulation on a large size negative ion accelerator with multiple extraction apertures and acceleration grids for fusion application was experimentally examined and designed. In the experiment, vacuum insulation characteristics were investigated in the JT-60 negative ion source with >1000 apertures on the grid with the surface area of {approx}2 m{sup 2}. The sustainable voltages varied with a square root of the gap lengths between the grids, and decreased with number of the apertures and with the surface area of the grids. Based on the obtained results, the JT-60SA (super advanced) negative ion source is designed to produce 22 A, 500 keV D{sup -} ion beams for 100 s.

  14. International Symposium on Daylighting Buildings (IEA SHC TASK 31) Integrating Automated Shading and Smart Glazings with Daylight

    E-Print Network [OSTI]

    International Symposium on Daylighting Buildings (IEA SHC TASK 31) Integrating Automated Shading and Smart Glazings with Daylight Controls Stephen Selkowitz Eleanor Lee Lawrence Berkeley National Laboratory Keywords: daylighting, controls, smart glazing, shading, field testing, IEA31 1. INTRODUCTION Most

  15. Thermal Insulation Systems

    E-Print Network [OSTI]

    Stanley, T. F.

    1982-01-01T23:59:59.000Z

    Thermal insulation systems are receiving a high degree of attention in view of increasing energy cost. Industrial, commercial and residential energy users are all well aware of energy cost increases and great emphasis is being directed to energy...

  16. Method for minimizing contaminant particle effects in gas-insulated electrical apparatus

    DOE Patents [OSTI]

    Pace, M.O.; Adcock, J.L.; Christophorou, L.G.

    1984-01-01T23:59:59.000Z

    Electrical breakdown of a gas insulator in high voltage apparatus is prevented by placing an electrical insulative coating on contaminant particles in the gas insulator.

  17. Method for minimizing contaminant particle effects in gas-insulated electrical apparatus

    DOE Patents [OSTI]

    Pace, Marshall O. (Knoxville, TN); Adcock, James L. (Knoxville, TN); Christophorou, Loucas G. (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

    Electrical breakdown of a gas insulator in high voltage apparatus is preved by placing an electrical insulative coating on contaminant particles in the gas insulator.

  18. Insulation fact sheet

    SciTech Connect (OSTI)

    NONE

    1997-08-01T23:59:59.000Z

    Electricity bills, oil bills, gas bills - all homeowners pay for one or more of these utilities, and wish they paid less. Often many of us do not really know how to control or reduce our utility bills. We resign ourselves to high bills because we think that is the price we have to pay for a comfortable home. We encourage our children to turn off the lights and appliances, but may not recognize the benefits of insulating the attic. This publication provides facts relative to home insulation. It discusses where to insulate, what products to use, the decision making process, installation options, and sources of additional information.

  19. Use of high temperature insulation for ceramic matrix composites in gas turbines

    DOE Patents [OSTI]

    Morrison, Jay Alan (Orlando, FL); Merrill, Gary Brian (Pittsburgh, PA); Ludeman, Evan McNeil (New Boston, NH); Lane, Jay Edgar (Murrysville, PA)

    2001-01-01T23:59:59.000Z

    A ceramic composition for insulating components, made of ceramic matrix composites, of gas turbines is provided. The composition comprises a plurality of hollow oxide-based spheres of various dimensions, a phosphate binder, and at least one oxide filler powder, whereby the phosphate binder partially fills gaps between the spheres and the filler powders. The spheres are situated in the phosphate binder and the filler powders such that each sphere is in contact with at least one other sphere and the arrangement of spheres is such that the composition is dimensionally stable and chemically stable at a temperature of approximately 1600.degree. C. A stationary vane of a gas turbine comprising the composition of the present invention bonded to the outer surface of the vane is provided. A combustor comprising the composition bonded to the inner surface of the combustor is provided. A transition duct comprising the insulating coating bonded to the inner surface of the transition is provided. Because of abradable properties of the composition, a gas turbine blade tip seal comprising the composition also is provided. The composition is bonded to the inside surface of a shroud so that a blade tip carves grooves in the composition so as to create a customized seal for the turbine blade tip.

  20. Cooper Pairs in Insulators?!

    ScienceCinema (OSTI)

    James Valles

    2010-01-08T23:59:59.000Z

    Nearly 50 years elapsed between the discovery of superconductivity and the emergence of the microscopic theory describing this zero resistance state. The explanation required a novel phase of matter in which conduction electrons joined in weakly bound pairs and condensed with other pairs into a single quantum state. Surprisingly, this Cooper pair formation has also been invoked to account for recently uncovered high-resistance or insulating phases of matter. To address this possibility, we have used nanotechnology to create an insulating system that we can probe directly for Cooper pairs. I will present the evidence that Cooper pairs exist and dominate the electrical transport in these insulators and I will discuss how these findings provide new insight into superconductor to insulator quantum phase transitions. 

  1. Transport phenomena in intrinsic semiconductors and insulators at high current densities: Suppression of the broken neutrality drift

    SciTech Connect (OSTI)

    Mnatsakanov, T. T.; Tandoev, A. G.; Yurkov, S. N. [All-Russia Electrotechnical Institute, Krasnokazarmennaya 12, 111250 Moscow (Russian Federation)] [All-Russia Electrotechnical Institute, Krasnokazarmennaya 12, 111250 Moscow (Russian Federation); Levinshtein, M. E. [The Ioffe Physico-Technical Institute, Politekhnicheskaya 26, 194021 St. Petersburg (Russian Federation)] [The Ioffe Physico-Technical Institute, Politekhnicheskaya 26, 194021 St. Petersburg (Russian Federation)

    2013-08-14T23:59:59.000Z

    It is shown that, in addition to the diffusion and broken neutrality drift (BND) modes well-known for insulators and very lightly doped semiconductors, the quasineutral drift (QND) mode is possible. The transition from the BND to QND mode is accompanied by the appearance of a portion with a very sharp current rise in the current-voltage characteristic. This effect is observed in a new type of semiconductor detectors (CIDs, Current Injected Detectors) of high-intensity neutron and proton radiation, suggested, in particular, for Large Hadron Collider. The effect is unambiguously attributed now to the presence of radiation-induced deep centers in a semiconductor. It is shown, however, in this paper that the effect of a very sharp rise in current upon a slight increase in voltage is even possible when there are no deep centers. An equation adequately describing the possible transport modes in intrinsic semiconductors and insulators is derived. The results of an analytical study are confirmed by an adequate simulation.

  2. Impact of Different Glazing Systems on Cooling Load of a Detached Residential Building at Bhubaneswar, India

    E-Print Network [OSTI]

    Sahoo, P. K.; Sahoo, R.

    2010-01-01T23:59:59.000Z

    assuming north?south and east?west facings of the building. For each orientation, different types of glazing (Table 4) and different glazing areas are considered. The first case(the base case) assumes a single clear glazing with a window-to-wall ratio.... Floor plan of the east-west oriented residential building taken for study (not to scale) Table 1. The zones basic characteristics Zone Area (m2) Volume (m3) Occupancy (people/m2) Venti- lation (l/s) HVAC system Bed room1 15.12 52...

  3. Large Fermi energy modulation in graphene transistors with high-pressure O{sub 2}-annealed Y{sub 2}O{sub 3} topgate insulators

    SciTech Connect (OSTI)

    Kanayama, Kaoru; Nagashio, Kosuke, E-mail: nagashio@material.t.u-tokyo.ac.jp; Nishimura, Tomonori; Toriumi, Akira [Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2014-02-24T23:59:59.000Z

    We demonstrate a considerable suppression of the low-field leakage through a Y{sub 2}O{sub 3} topgate insulator on graphene by applying high-pressure O{sub 2} at 100?atm during post-deposition annealing (HP-PDA). Consequently, the quantum capacitance measurement for the monolayer graphene reveals the largest Fermi energy modulation (E{sub F}?=??0.52?eV, i.e., the carrier density of ?2?×?10{sup 13}?cm{sup ?2}) in the solid-state topgate insulators reported so far. HP-PDA is the robust method to improve the electrical quality of high-k insulators on graphene.

  4. Superconducting Topological Insulators

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

    Superconducting Topological Insulators Superconducting Topological Insulators Print Wednesday, 26 January 2011 00:00 Three-dimensional topological insulators (TIs), discovered...

  5. Recovery Act: Electrochromic Glazing Technology: Improved Performance, Lower Price

    SciTech Connect (OSTI)

    Burdis, Mark; Sbar, Neil

    2012-06-30T23:59:59.000Z

    The growing dependency of the US on energy imports and anticipated further increases in energy prices reinforce the concerns about meeting the energy demand in the future and one element of a secure energy future is conservation. It is estimated that the buildings sector represents 40% of the US's total energy consumption. And buildings produce as much as one third of the greenhouse gas emissions primarily through fossil fuel usage during their operational phase. A significant fraction of this energy usage is simply due to inefficient window technology. Electrochromic (EC) windows allow electronic control of their optical properties so that the transparency to light can be adjusted from clear to dark. This ability to control the amount of solar energy allowed into the building can be advantageously used to minimize lighting, heating and air conditioning costs. Currently, the penetration of EC windows into the marketplace is extremely small, and consequently there is a huge opportunity for energy savings if this market can be expanded. In order to increase the potential energy savings it is necessary to increase the quantity of EC windows in operation. Additionally, any incremental improvement in the energy performance of each window will add to the potential energy savings. The overall goals of this project were therefore to improve the energy performance and lower the cost of dynamic (EC) smart windows for residential and commercial building applications. This project is obviously of benefit to the public by addressing two major areas: lowering the cost and improving the energy performance of EC glazings. The high level goals for these activities were: (i) to improve the range between the clear and the tinted state, (ii) reduce the price of EC windows by utilizing lower cost materials, (iii) lowering the U-Value1 SAGE Electrochromics Inc. is the only company in the US which has a track record of producing EC windows, and presently has a small operational factory in Faribault MN which is shipping products throughout the world. There is a much larger factory currently under construction close by. This project was targeted specifically to address the issues outlined above, with a view to implementation on the new high volume manufacturing facility. Each of the Tasks which were addressed in this project is relatively straightforward to implement in this new facility and so the benefits of the work will be realized quickly. , and (iv) ensure the proposed changes have no detrimental effect to the proven durability of the window. The research described here has helped to understand and provide solutions to several interesting and previously unresolved issues of the technology as well as make progress in areas which will have a significant impact on energy saving. In particular several materials improvements have been made, and tasks related to throughput and yield improvements have been completed. All of this has been accomplished without any detrimental effect on the proven durability of the SageGlass EC device. The project was divided into four main areas: 1. Improvement of the Properties of the EC device by material enhancements (Task 2); 2. Reduce the cost of production by improving the efficiency and yields of some key manufacturing processes (Task 3); 3. Further reduce the cost by significant modifications to the structure of the device (Task 4); 4. Ensure the durability of the EC device is not affected by any of the changes resulting from these activities (Task 5). A detailed description of the activities carried out in these areas is given in the following report, along with the aims and goals of the work. We will see that we have completed Tasks 2 and 3 fully, and the durability of the resulting device structure has been unaffected. Some of Task 4 was not carried out because of difficulties with integrating the installation of the required targets into the production coater due to external constraints not related to this project. We will also see that the durability of the devices produced as a result of this work was

  6. Thermal properties of granular silica aerogel for high-performance insulation systems

    E-Print Network [OSTI]

    Neugebauer, Adam (Adam Halbert)

    2013-01-01T23:59:59.000Z

    Based on mounting evidence in support of anthropogenic global climate change, there is an urgency for developments in high-performance building techniques and technologies. New construction projects provide substantial ...

  7. Dielectric-wall linear accelerator with a high voltage fast rise time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators

    DOE Patents [OSTI]

    Caporaso, G.J.; Sampayan, S.E.; Kirbie, H.C.

    1998-10-13T23:59:59.000Z

    A dielectric-wall linear accelerator is improved by a high-voltage, fast rise-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface. 12 figs.

  8. Simulation of complex glazing products; from optical data measurements to model based predictive controls

    SciTech Connect (OSTI)

    Kohler, Christian

    2012-08-01T23:59:59.000Z

    Complex glazing systems such as venetian blinds, fritted glass and woven shades require more detailed optical and thermal input data for their components than specular non light-redirecting glazing systems. Various methods for measuring these data sets are described in this paper. These data sets are used in multiple simulation tools to model the thermal and optical properties of complex glazing systems. The output from these tools can be used to generate simplified rating values or as an input to other simulation tools such as whole building annual energy programs, or lighting analysis tools. I also describe some of the challenges of creating a rating system for these products and which factors affect this rating. A potential future direction of simulation and building operations is model based predictive controls, where detailed computer models are run in real-time, receiving data for an actual building and providing control input to building elements such as shades.

  9. A cost and benefit analysis of future end-of-life vehicle glazing recycling in France: a

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and aluminum, and not minor wastes such as glazing (Gerrard and Kandlikar 2007). The new recycling target (95 and polluted with organic material. The treatment and recycling of glass does however become difficult1 A cost and benefit analysis of future end-of- life vehicle glazing recycling in France

  10. Application of High-Performance Aerogel Insulating Materials (Analysis & Test Results)

    SciTech Connect (OSTI)

    Goranson, Paul L [ORNL; Freudenberg, Kevin D [ORNL; McGinnis, William Dean [ORNL; Dudek, L. [Princeton Plasma Physics Laboratory (PPPL); Zarnstorff, M. C. [Princeton Plasma Physics Laboratory (PPPL)

    2009-01-01T23:59:59.000Z

    The NCSX stellarator core design is built around a 3-period, highly shaped plasma with an assembly of four magnet systems, the TF coils (TF), the Modular Coils (MC), the PF Coils (PF), and the Trim Coils, that surrounds an all welded Vacuum Vessel (VV). The VV features approximately 100 ports for heating, pumping, diagnostics, and maintenance access. The entire system is surrounded by a cryostat to permit operation of the coils at liquid nitrogen temperature. The VV and coils are assembled in 120 segments. The VV segments must be placed inside the MC by sliding the coils over each end of the vessel subassembly. Installation of the port extensions is done after this operation. They are slipped through access holes in the MC onto port stubs and welded on from inside. Figures 1 & 2 illustrate the assembly of the MC over a VV section and installation of TF and port extensions to complete a sector of the VV.

  11. Strained-Si-on-Insulator (SSOI) and SiGe-on-Insulator (SGOI): Fabrication Obstacles and Solutions

    E-Print Network [OSTI]

    Strained-Si-on-Insulator (SSOI) and SiGe-on-Insulator (SGOI): Fabrication Obstacles and Solutions-Si and SiGe-on-insulator were fabricated, combining both the benefits of high-mobility strained-Si and SOI) to oxidized handle wafers. Layer transfer onto insulating handle wafers can be accomplished using grind

  12. Topological insulators/Isolants topologiques An introduction to topological insulators

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Topological insulators/Isolants topologiques An introduction to topological insulators Introduction topology, the insulator is called a topological insulator. We introduce this notion of topological order sont finalement discutées. Keywords: topological insulator, topological band theory, quantum anomalous

  13. Fully synthetic taped insulation cables

    DOE Patents [OSTI]

    Forsyth, Eric B. (Brookhaven, NY); Muller, Albert C. (Center Moriches, NY)

    1984-01-01T23:59:59.000Z

    A high voltage oil-impregnated electrical cable with fully polymer taped insulation operable to 765 kV. Biaxially oriented, specially processed, polyethylene, polybutene or polypropylene tape with an embossed pattern is wound in multiple layers over a conductive core with a permeable screen around the insulation. Conventional oil which closely matches the dielectric constant of the tape is used, and the cable can be impregnated after field installation because of its excellent impregnation characteristics.

  14. Gas filled panel insulation

    DOE Patents [OSTI]

    Griffith, B.T.; Arasteh, D.K.; Selkowitz, S.E.

    1993-12-14T23:59:59.000Z

    A structural or flexible highly insulative panel which may be translucent, is formed from multi-layer polymeric material in the form of an envelope surrounding a baffle. The baffle is designed so as to minimize heat transfer across the panel, by using material which forms substantially closed spaces to suppress convection of the low conductivity gas fill. At least a portion of the baffle carries a low emissivity surface for suppression of infrared radiation. 18 figures.

  15. IEA-SHC Task 27: Environmental Performance Assessment of glazing and windows: context, overview, main concerns

    E-Print Network [OSTI]

    IEA-SHC Task 27: Environmental Performance Assessment of glazing and windows: context, overview and objectives, and most often of limited use in other contexts. A short review of the studies already performed the work undertaken within the programme of IEA/SHCP/Task 27, which will be presented in the third part

  16. Enhancement of Topological Insulators Surface Conduction

    E-Print Network [OSTI]

    Yu, Xinxin

    2012-01-01T23:59:59.000Z

    Enhancement of Topological Insulators Surface Conduction AEnhancement of Topological Insulators Surface Conduction byTopological Insulator

  17. Multiple density layered insulator

    DOE Patents [OSTI]

    Alger, T.W.

    1994-09-06T23:59:59.000Z

    A multiple density layered insulator for use with a laser is disclosed which provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation. 4 figs.

  18. Multiple density layered insulator

    DOE Patents [OSTI]

    Alger, Terry W. (Tracy, CA)

    1994-01-01T23:59:59.000Z

    A multiple density layered insulator for use with a laser is disclosed wh provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation.

  19. Silicon-on-insulator-based high-voltage, high-temperature integrated circuit gate driver for silicon carbide-based power field effect transistors

    SciTech Connect (OSTI)

    Tolbert, Leon M [ORNL; Huque, Mohammad A [ORNL; Blalock, Benjamin J [ORNL; Islam, Syed K [ORNL

    2010-01-01T23:59:59.000Z

    Silicon carbide (SiC)-based field effect transistors (FETs) are gaining popularity as switching elements in power electronic circuits designed for high-temperature environments like hybrid electric vehicle, aircraft, well logging, geothermal power generation etc. Like any other power switches, SiC-based power devices also need gate driver circuits to interface them with the logic units. The placement of the gate driver circuit next to the power switch is optimal for minimising system complexity. Successful operation of the gate driver circuit in a harsh environment, especially with minimal or no heat sink and without liquid cooling, can increase the power-to-volume ratio as well as the power-to-weight ratio for power conversion modules such as a DC-DC converter, inverter etc. A silicon-on-insulator (SOI)-based high-voltage, high-temperature integrated circuit (IC) gate driver for SiC power FETs has been designed and fabricated using a commercially available 0.8--m, 2-poly and 3-metal bipolar-complementary metal oxide semiconductor (CMOS)-double diffused metal oxide semiconductor (DMOS) process. The prototype circuit-s maximum gate drive supply can be 40-V with peak 2.3-A sourcing/sinking current driving capability. Owing to the wide driving range, this gate driver IC can be used to drive a wide variety of SiC FET switches (both normally OFF metal oxide semiconductor field effect transistor (MOSFET) and normally ON junction field effect transistor (JFET)). The switching frequency is 20-kHz and the duty cycle can be varied from 0 to 100-. The circuit has been successfully tested with SiC power MOSFETs and JFETs without any heat sink and cooling mechanism. During these tests, SiC switches were kept at room temperature and ambient temperature of the driver circuit was increased to 200-C. The circuit underwent numerous temperature cycles with negligible performance degradation.

  20. The use of coated micropowders to reduce radiation heat transfer in foam insulation

    E-Print Network [OSTI]

    Marge, Arlene Lanciani

    1991-01-01T23:59:59.000Z

    Polyurethane foam is the most effective insulation currently available for buildings. Chlorofluorocarbon (CFC) blowing agents, which have low thermal conductivities, contribute highly to the effectiveness of this insulation. ...

  1. Sierra Designs 20 degrees F Wild Bill Climashield Sleeping Bag ClimashieldTM HL, a high-loft continuous filament insulation, offers excellent thermal

    E-Print Network [OSTI]

    Walker, Lawrence R.

    -loft continuous filament insulation, offers excellent thermal efficiency, durability and water resistance Chest to create a pillow; no need for a pillow to take up valuable space in your backpack Insulated draft tube

  2. Exploring the possibility of low temperature glazing in faience from the Djoser Step Pyramid through compositional analysis

    E-Print Network [OSTI]

    Whisenant, Lawrence A

    2012-01-01T23:59:59.000Z

    Egyptian faience, a glazed, non-clay based ceramic material, is found throughout Egypt in a time range pre-dating the Predynastic Period (5500 - 3100 BCE) and extending well beyond the Roman Period (30 BCE - 641 CE). One ...

  3. Transport properties in the vicinity of Mott insulators

    E-Print Network [OSTI]

    Nave, Cody Patrick, 1980-

    2007-01-01T23:59:59.000Z

    Understanding the states in the vicinity of the Mott insulator is crucial to understanding both the physics of the transition between a Mott insulating phase and a metallic phase and the physics of the cuprate high-temperature ...

  4. ITER CENTRAL SOLENOID COIL INSULATION QUALIFICATION

    SciTech Connect (OSTI)

    Martovetsky, N N; Mann, T L; Miller, J R; Freudenberg, K D; Reed, R P; Walsh, R P; McColskey, J D; Evans, D

    2009-06-11T23:59:59.000Z

    An insulation system for ITER Central Solenoid must have sufficiently high electrical and structural strength. Design efforts to bring stresses in the turn and layer insulation within allowables failed. It turned out to be impossible to eliminate high local tensile stresses in the winding pack. When high local stresses can not be designed out, the qualification procedure requires verification of the acceptable structural and electrical strength by testing. We built two 4 x 4 arrays of the conductor jacket with two options of the CS insulation and subjected the arrays to 1.2 million compressive cycles at 60 MPa and at 76 K. Such conditions simulated stresses in the CS insulation. We performed voltage withstand tests and after end of cycling we measured the breakdown voltages between in the arrays. After that we dissectioned the arrays and studied micro cracks in the insulation. We report details of the specimens preparation, test procedures and test results.

  5. ITER Central Solenoid Coil Insulation Qualification

    SciTech Connect (OSTI)

    Martovetsky, Nicolai N [ORNL] [ORNL; Mann Jr, Thomas Latta [ORNL] [ORNL; Miller, John L [ORNL] [ORNL; Freudenberg, Kevin D [ORNL] [ORNL; Reed, Richard P [Cryogenic Materials, Inc.] [Cryogenic Materials, Inc.; Walsh, Robert P [Florida State University] [Florida State University; McColskey, J D [National Institute of Standards and Technology (NIST), Boulder] [National Institute of Standards and Technology (NIST), Boulder; Evans, D [Advanced Cryogenic Materials] [Advanced Cryogenic Materials

    2010-01-01T23:59:59.000Z

    An insulation system for ITER Central Solenoid must have sufficiently high electrical and structural strength. Design efforts to bring stresses in the turn and layer insulation within allowables failed. It turned out to be impossible to eliminate high local tensile stresses in the winding pack. When high local stresses can not be designed out, the qualification procedure requires verification of the acceptable structural and electrical strength by testing. We built two 4x4 arrays of the conductor jacket with two options of the CS insulation and subjected the arrays to 1.2 million compressive cycles at 60 MPa and at 76 K. Such conditions simulated stresses in the CS insulation. We performed voltage withstand tests and after end of cycling we measured the breakdown voltages between in the arrays. After that we dissectioned the arrays and studied micro cracks in the insulation. We report details of the specimens preparation, test procedures and test results.

  6. Membranes Improve Insulation Efficiency

    E-Print Network [OSTI]

    Bullock, C. A.

    1986-01-01T23:59:59.000Z

    No Clear White Alum Temp Mem Mem Mem Foil FIGURE 7 Temperature Inside Room and Temperature Next to Top of Sheetrock Under Various insulation Configurations. It should be noted that after this test was completed, the fiber insulation was inspected...

  7. Inner surface flash-over of insulator of low-inductance high-voltage self-breakdown gas switch and its application

    SciTech Connect (OSTI)

    Zhang, Hong-bo, E-mail: walkman67@163.com; Liu, Jin-liang [College of Opto-electronic Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China)] [College of Opto-electronic Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China)

    2014-04-15T23:59:59.000Z

    In this paper, the inner surface flash-over of high-voltage self-breakdown switch, which is used as a main switch of pulse modulator, is analyzed in theory by employing the method of distributed element equivalent circuit. Moreover, the field distortion of the switch is simulated by using software. The results of theoretical analysis and simulation by software show that the inner surface flash-over usually starts at the junction points among the stainless steel, insulator, and insulation gas in the switch. A switch with improved structure is designed and fabricated according to the theoretical analysis and simulation results. Several methods to avoid inner surface flash-over are used to improve the structure of switch. In experiment, the inductance of the switch is no more than 100 nH, the working voltage of the switch is about 600 kV, and the output voltage and current of the accelerator is about 500 kV and 50 kA, respectively. And the zero-to-peak rise time of output voltage at matched load is less than 30 ns due to the small inductance of switch. The original switch was broken-down after dozens of experiments, and the improved switch has been worked more than 200 times stably.

  8. Insulating polymer concrete

    DOE Patents [OSTI]

    Schorr, H. Peter (Douglaston, NY); Fontana, Jack J. (Shirley, NY); Steinberg, Meyer (Melville, NY)

    1987-01-01T23:59:59.000Z

    A lightweight insulating polymer concrete formed from a lightweight closed cell aggregate and a water resistance polymeric binder.

  9. Topological Insulators & Superconductors

    E-Print Network [OSTI]

    Topological Insulators & Superconductors New Frontiers in Low-Dimensional Systems Program 3-5 November 2010 Jadwin Hall, Fourth Floor, Room 407 Topological Insulators and Superconductors have quickly Insulators and Superconductors will gather the world- leading researchers in this field to present recent

  10. Reduction in Vehicle Temperatures and Fuel Use from Cabin Ventilation, Solar-Reflective Paint, and a New Solar-Reflective Glazing

    SciTech Connect (OSTI)

    Rugh, J.; Chaney, L.; Meyer, J.; Rustagi, M.; Olson, K.; Kogler, R.

    2007-05-01T23:59:59.000Z

    An analysis to determine the impact of reducing the thermal load on a vehicle using solar-reflective paint and glazing.

  11. Thermal Insulation Performance in the Process Industries: Facts and Fallacies

    E-Print Network [OSTI]

    Tye, R. P.

    on Industrial Insulation," Eurima-News, Roskilde, Denmark (October, 1979). 4. "High Temperature Thermal Insulation Usage in the U.K. Process Industries," UKAEA, Harwell, Report, 1982. 5. Tye, R.P., J. Thermal Insulation 2., 69, July, 1983. 6. Tye, R...

  12. Vacuum insulation tandem accelerator for B. Bayanov1

    E-Print Network [OSTI]

    Taskaev, Sergey Yur'evich

    273 Vacuum insulation tandem accelerator for NCT B. Bayanov1 , Yu. Belchenko1 , V. Belov1 , G of high current hydrogen negative ions by special geometry of potential electrodes with vacuum insulation. Fig. 1 shows the construction of vacuum insulation tandem accelerator developed at BINP, as a base

  13. Process for making ceramic insulation

    DOE Patents [OSTI]

    Akash, Akash (Salt Lake City, UT); Balakrishnan, G. Nair (Sandy, UT)

    2009-12-08T23:59:59.000Z

    A method is provided for producing insulation materials and insulation for high temperature applications using novel castable and powder-based ceramics. The ceramic components produced using the proposed process offers (i) a fine porosity (from nano-to micro scale); (ii) a superior strength-to-weight ratio; and (iii) flexibility in designing multilayered features offering multifunctionality which will increase the service lifetime of insulation and refractory components used in the solid oxide fuel cell, direct carbon fuel cell, furnace, metal melting, glass, chemical, paper/pulp, automobile, industrial heating, coal, and power generation industries. Further, the ceramic components made using this method may have net-shape and/or net-size advantages with minimum post machining requirements.

  14. High performance organic field-effect transistors with ultra-thin HfO{sub 2} gate insulator deposited directly onto the organic semiconductor

    SciTech Connect (OSTI)

    Ono, S., E-mail: shimpei@criepi.denken.or.jp [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan); Häusermann, R. [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan) [Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511 (Japan); Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland); Chiba, D. [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan) [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho Kawaguchi, Saitama 322-0012 (Japan); Department of Applied Physics, University of Tokyo, Tokyo 113-8656 (Japan); Shimamura, K.; Ono, T. [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)] [Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Batlogg, B. [Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland)] [Laboratory for Solid State Physics, ETH Zurich, Zurich 8093 (Switzerland)

    2014-01-06T23:59:59.000Z

    We have produced stable organic field-effect transistors (OFETs) with an ultra-thin HfO{sub 2} gate insulator deposited directly on top of rubrene single crystals by atomic layer deposition (ALD). We find that ALD is a gentle deposition process to grow thin films without damaging rubrene single crystals, as results these devices have a negligibly small threshold voltage and are very stable against gate-bias-stress, and the mobility exceeds 1 cm{sup 2}/V s. Moreover, the devices show very little degradation even when kept in air for more than 2 months. These results demonstrate thin HfO{sub 2} layers deposited by ALD to be well suited as high capacitance gate dielectrics in OFETs operating at small gate voltage. In addition, the dielectric layer acts as an effective passivation layer to protect the organic semiconductor.

  15. Insulated laser tube structure and method of making same

    DOE Patents [OSTI]

    Dittbenner, Gerald R. (4353 Findlay Way, Livermore, CA 94550)

    1999-01-01T23:59:59.000Z

    An insulated high temperature ceramic laser tube having substantially uniform insulation along the length of the tube is disclosed having particulate ceramic insulation positioned between the outer wall of the ceramic laser tube and the inner surface of tubular ceramic fiber insulation which surrounds the ceramic laser tube. The particulate ceramic insulation is preferably a ceramic capable of sintering to the outer surface of the ceramic laser tube and to the inner surface of the tubular ceramic fiber insulation. The addition of the particulate ceramic insulation to fill all the voids between the ceramic laser tube and the fibrous ceramic insulation permits the laser tube to be operated at a substantially uniform temperature throughout the length of the laser tube.

  16. A Simple Holographic Insulator

    E-Print Network [OSTI]

    Eric Mefford; Gary T. Horowitz

    2014-07-11T23:59:59.000Z

    We present a simple holographic model of an insulator. Unlike most previous holographic insulators, the zero temperature infrared geometry is completely nonsingular. Both the low temperature DC conductivity and the optical conductivity at zero temperature satisfy power laws with the same exponent, given by the scaling dimension of an operator in the IR. Changing a parameter in the model converts it from an insulator to a conductor with a standard Drude peak.

  17. Irradiation requirements of Nb3Sn based SC magnets electrical insulation

    E-Print Network [OSTI]

    McDonald, Kirk

    Irradiation requirements of Nb3Sn based SC magnets electrical insulation developed within the Eu electrical insulation candidates · EuCARD insulators certification conditions · Post irradiation tests and neutrino factories will be subjected to very high radiation doses. · The electrical insulation employed

  18. Pipe Insulation Economies

    E-Print Network [OSTI]

    Schilling, R. E.

    PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram written in IBM basic to simplify the economic insulation thickness for an insulated pipe. Many... ECONOMIES" 30 LOCATE 10,29:PRINT"ROBERT E. SCHILLING,P.E." 40 LOCATE l2,3l:PRINT"EATON CORPORATION" 50 LOCATE l3,26:PRINT"119 Q SOUTH CHILLICOTHE ROAD" 598 ESL-IE-86-06-97 Proceedings from the Eighth Annual Industrial Energy Technology Conference...

  19. Load responsive multilayer insulation performance testing

    SciTech Connect (OSTI)

    Dye, S.; Kopelove, A. [Quest Thermal Group, 6452 Fig Street Suite A, Arvada, CO 80004 (United States); Mills, G. L. [Ball Aerospace and Technologies Corp, 1600 Commerce Street, Boulder, CO 80301 (United States)

    2014-01-29T23:59:59.000Z

    Cryogenic insulation designed to operate at various pressures from one atmosphere to vacuum, with high thermal performance and light weight, is needed for cryogenically fueled space launch vehicles and aircraft. Multilayer insulation (MLI) performs well in a high vacuum, but the required vacuum shell for use in the atmosphere is heavy. Spray-on foam insulation (SOFI) is often used in these systems because of its light weight, but can have a higher heat flux than desired. We report on the continued development of Load Responsive Multilayer Insulation (LRMLI), an advanced thermal insulation system that uses dynamic beam discrete spacers that provide high thermal performance both in atmosphere and vacuum. LRMLI consists of layers of thermal radiation barriers separated and supported by micromolded polymer spacers. The spacers have low thermal conductance, and self-support a thin, lightweight vacuum shell that provides internal high vacuum in the insulation. The dynamic load responsive spacers compress to support the external load of a vacuum shell in one atmosphere, and decompress under reduced atmospheric pressure for lower heat leak. Structural load testing was performed on the spacers with various configurations. LRMLI was installed on a 400 liter tank and boil off testing with liquid nitrogen performed at various chamber pressures from one atmosphere to high vacuum. Testing was also performed with an MLI blanket on the outside of the LRMLI.

  20. A New Generation of Building Insulation by Foaming Polymer Blend...

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

    insulation technologies available on the market. Instead of hydroflurocarbon, it uses carbon dioxide as the blowing agent. This technology represents a highly valuable market...

  1. Measure Guideline: Internal Insulation of Masonry Walls

    SciTech Connect (OSTI)

    Straube, J. F.; Ueno, K.; Schumacher, C. J.

    2012-07-01T23:59:59.000Z

    This measure guideline provides recommendations for interior insulation assemblies that control interstitial condensation and durability risks; recommendations for acceptable thermal performance are also provided. An illustrated guide of high-risk exterior details (which concentrate bulk water), and recommended remediation details is provided. This is followed by a recommended methodology for risk assessment of a masonry interior insulation project: a series of steps are suggested to assess the risks associated with this retrofit, with greater certainty with added steps.

  2. Highly tunable electron transport in epitaxial topological insulator (Bi{sub 1-x}Sb{sub x}){sub 2}Te{sub 3} thin films

    SciTech Connect (OSTI)

    He Xiaoyue; Guan Tong; Wang Xiuxia; Feng Baojie; Cheng Peng; Chen Lan; Li Yongqing; Wu Kehui [Institute of Physics, Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2012-09-17T23:59:59.000Z

    Atomically smooth, single crystalline (Bi{sub 1-x}Sb{sub x}){sub 2}Te{sub 3} films have been grown on SrTiO{sub 3}(111) substrates by molecular beam epitaxy. A full range of Sb-Bi compositions have been studied in order to obtain the lowest possible bulk conductivity. For the samples with optimized Sb compositions (x=0.5{+-}0.1), the carrier type can be tuned from n-type to p-type across the whole thickness with the help of a back-gate. Linear magnetoresistance has been observed at gate voltages close to the maximum in the longitudinal resistance of a (Bi{sub 0.5}Sb{sub 0.5}){sub 2}Te{sub 3} sample. These highly tunable (Bi{sub 1-x}Sb{sub x}){sub 2}Te{sub 3} thin films provide an excellent platform to explore the intrinsic transport properties of the three-dimensional topological insulators.

  3. Cooper-Pair Injection into Topological Insulators and Helical Wires

    E-Print Network [OSTI]

    Sato, Koji

    2013-01-01T23:59:59.000Z

    Topological Insulator . . . . . . . . . . . . . . . . . . . . . . . .phenomena : Topological Insulators and Superconductors. ”Colloquium : Topological insulators. ” Rev. Mod. Phys. , 82:

  4. Insulator for laser housing

    DOE Patents [OSTI]

    Duncan, D.B.

    1992-12-29T23:59:59.000Z

    The present invention provides a heat-resistant electrical insulator adapted for joining laser housing portions, which insulator comprises: an annulus; a channel in the annulus traversing the circumference and length of the housing; at least two ports, each communicating with the channel and an outer surface of the housing; and an attachment for securely attaching each end of the annulus to a laser housing member. 3 figs.

  5. Insulator for laser housing

    DOE Patents [OSTI]

    Duncan, David B. (Auburn, CA)

    1992-01-01T23:59:59.000Z

    The present invention provides a heat-resistant electrical insulator adapted for joining laser housing portions, which insulator comprises: an annulus; a channel in the annulus traversing the circumference and length of the housing; at least two ports, each communicating with the channel and an outer surface of the housing; and an attachment for securely attaching each end of the annulus to a laser housing member.

  6. A Study of the Filling of Wall Cavities With Retrofit Wall Insulation.

    SciTech Connect (OSTI)

    Flores, Joseph A.; Grill, Alan R.

    1988-08-01T23:59:59.000Z

    The Pacific Northwest Power Marketing Agency, the Bonneville Power Administration (BPA), conducted a retrofit wall insulation study to determine the effects of various obstructions within a wall cavity, where voids are likely to occur, and preferred filling methods and material types. The insulation test structure was composed of four 8-foot /times/ 12-foot walls, and was built using standard construction practices. The inside walls were clear plastic glazing, instead of gypsum board, to enable viewing of the filling process. A total of eight tests were performed: four cellulose, two rockwool, and two fiberglass. One- and two-hole filling methods were observed. All insulations were found to perform in the same basic manner with all experiencing the same problem areas. Common installer problems were empty spaces at the tops of cavities and missed cavities, especially above headers. Wiring and lath and plaster consistently caused reduced insulation densities in cavities. The problems with wiring, lath and plaster, and other features in the wall cavities were avoided with the use of a filler tube. The filler tube also provided a more consistent fill along the length of the entire cavity. 2 figs., 3 tabs.

  7. Design Tool for Cryogenic Thermal Insulation Systems

    SciTech Connect (OSTI)

    Demko, Jonathan A [ORNL] [ORNL; Fesmire, J. E. [NASA Kennedy Space Center, Kennedy Space Center, Florida] [NASA Kennedy Space Center, Kennedy Space Center, Florida; Augustynowicz, S. D. [Sierra Lobo Inc., Kennedy Space Center, Florida] [Sierra Lobo Inc., Kennedy Space Center, Florida

    2008-01-01T23:59:59.000Z

    Thermal isolation of low-temperature systems from ambient environments is a constant issue faced by practitioners of cryogenics. For energy-efficient systems and processes to be realized, thermal insulation must be considered as an integrated system, not merely an add-on element. A design tool to determine the performance of insulation systems for comparative trade-off studies of different available material options was developed. The approach is to apply thermal analysis to standard shapes (plane walls, cylinders, spheres) that are relatively simple to characterize with a one-dimensional analytical or numerical model. The user describes the system hot and cold boundary geometry and the operating environment. Basic outputs such as heat load and temperature profiles are determined. The user can select from a built-in insulation material database or input user defined materials. Existing information has been combined with the new experimental thermal conductivity data produced by the Cryogenics Test Laboratory for cryogenic and vacuum environments, including high vacuum, soft vacuum, and no vacuum. Materials in the design tool include multilayer insulation, aerogel blankets, aerogel bulk-fill, foams, powders, composites, and other insulation system constructions. A comparison of the design tool to a specific composite thermal insulation system is given.

  8. Electoral Competition, Political Uncertainty and Policy Insulation

    E-Print Network [OSTI]

    de Figueiredo, Rui J. P. Jr.

    2001-01-01T23:59:59.000Z

    Uncertainty and Policy Insulation Horn, Murray. 1995. TheUncertainty and Policy Insulation United States Congress.UNCERTAINTY AND POLICY INSULATION Rui J. P. de Figueiredo,

  9. Basement Insulation Systems - Building America Top Innovation...

    Energy Savers [EERE]

    Basement Insulation Systems - Building America Top Innovation Basement Insulation Systems - Building America Top Innovation This photo shows a framed basement wall with insulation...

  10. Sheath insulator final test report, TFE Verification Program

    SciTech Connect (OSTI)

    Not Available

    1994-07-01T23:59:59.000Z

    The sheath insulator in a thermionic cell has two functions. First, the sheath insulator must electrically isolate the collector form the outer containment sheath tube that is in contact with the reactor liquid metal coolant. Second, The sheath insulator must provide for high uniform thermal conductance between the collector and the reactor coolant to remove away waste heat. The goals of the sheath insulator test program were to demonstrate that suitable ceramic materials and fabrication processes were available, and to validate the performance of the sheath insulator for TFE-VP requirements. This report discusses the objectives of the test program, fabrication development, ex-reactor test program, in-reactor test program, and the insulator seal specifications.

  11. Development of a methodology to discriminate incipient insulator faults from distribution system load

    E-Print Network [OSTI]

    Richards, Christopher Scott

    2000-01-01T23:59:59.000Z

    of incipient insulator faults 4. Determining characteristics most likely to discriminate incipient insulator faults from distribution system load current From this work, the aggregate of the non-harmonic components and the high frequency energy of the leakage...

  12. 1998 IEEE Int. Symp. on Electrical Insulation (Washington) page 1 of 4

    E-Print Network [OSTI]

    Judd, Martin

    1998 IEEE Int. Symp. on Electrical Insulation (Washington) page 1 of 4 HIGH BANDWIDTH MEASUREMENT. These pulses are of interest because when they occur in gas insulated substations they generate UHF signals of particle generated pulses under conditions similar to those present in high voltage gas insulated apparatus

  13. Fully synthetic taped insulation cables

    DOE Patents [OSTI]

    Forsyth, E.B.; Muller, A.C.

    1983-07-15T23:59:59.000Z

    The present invention is a cable which, although constructed from inexpensive polyolefin tapes and using typical impregnating oils, furnishes high voltage capability up to 765 kV, and has such excellent dielectric characteristics and heat transfer properties that it is capable of operation at capacities equal to or higher than presently available cables at a given voltage. This is accomplished by using polyethylene, polybutene or polypropylene insulating tape which has been specially processed to attain properties which are not generally found in these materials, but are required for their use in impregnated electrical cables. Chief among these properties is compatibility with impregnating oil.

  14. Notes on topological insulators

    E-Print Network [OSTI]

    Dan Li; Ralph M. Kaufmann; Birgit Wehefritz-Kaufmann

    2015-01-13T23:59:59.000Z

    This paper is a survey of the $\\mathbb{Z}/\\mathbb{Z}_2$-valued invariants of topological insulators in condensed matter physics. The $\\mathbb{Z}$-valued topological invariant was originally called the TKNN invariant in physics, which has been fully understood as the first Chern number. The $\\mathbb{Z}_2$ invariant is more mysterious, we will devote our efforts to reviewing its equivalent descriptions from different point of views. We emphasize that both invariants are realizations of the Atiyah--Singer index theorem in condensed matter physics. The topological K-theory also plays an important role in the classification of topological insulators with different symmetries.

  15. Topological Mott Insulators

    SciTech Connect (OSTI)

    Raghu, S.

    2010-03-02T23:59:59.000Z

    We consider extended Hubbard models with repulsive interactions on a honeycomb lattice, and the transitions from the semimetal to Mott insulating phases at half-filling. Because of the frustrated nature of the second-neighbor interactions, topological Mott phases displaying the quantum Hall and the quantum spin Hall effects are found for spinless and spin fermion models, respectively. The mean-field phase diagram is presented and the fluctuations are treated within the random phase approximation. Renormalization group analysis shows that these states can be favored over the topologically trivial Mott insulating states.

  16. Contaminant trap for gas-insulated apparatus

    DOE Patents [OSTI]

    Adcock, J.L.; Pace, M.O.; Christophorou, L.G.

    1984-01-01T23:59:59.000Z

    A resinous body is placed in gas-insulated electrical apparatus to remove particulate material from the insulating gas.

  17. Physics World Archive Topological insulators

    E-Print Network [OSTI]

    Johannesson, Henrik

    Physics World Archive Topological insulators Charles Kane, Joel Moore From Physics World February, how- ever, now uncovered a new electronic phase called a topological insulator. Putting the name; this "spin current" is a milestone in the realization of practical "spintronics". Topological insulators have

  18. Topological Insulator Nanowires and Nanoribbons

    E-Print Network [OSTI]

    Cui, Yi

    Topological Insulator Nanowires and Nanoribbons Desheng Kong, Jason C. Randel,,| Hailin Peng,, Judy material show that it is a three-dimensional topological insulator possessing conductive surface states topological insulator materials have a large surface-to-volume ratio that can manifest the conductive surface

  19. Holographic fractional topological insulators

    SciTech Connect (OSTI)

    Hoyos, Carlos; Jensen, Kristan; Karch, Andreas [Department of Physics, University of Washington, Seattle, Washington 98195-1560 (United States)

    2010-10-15T23:59:59.000Z

    We give a holographic realization of the recently proposed low-energy effective action describing a fractional topological insulator. In particular we verify that the surface of this hypothetical material supports a fractional quantum Hall current corresponding to half that of a Laughlin state.

  20. A pulser for medium-frequency modulated direct-current reactive sputter deposition of insulators

    E-Print Network [OSTI]

    Cao, Hui

    for medium-frequency modulated direct-current dc reactive sputter deposition of electrical insulators at the target surface inherent to high- deposition-rate reactive sputtering of electrical insulators. TypicallyA pulser for medium-frequency modulated direct-current reactive sputter deposition of insulators G

  1. The Insulator Binding Protein CTCF Positions 20 Nucleosomes around Its Binding Sites across the Human

    E-Print Network [OSTI]

    Weng, Zhiping

    The Insulator Binding Protein CTCF Positions 20 Nucleosomes around Its Binding Sites across occupied by the insulator binding protein CTCF across the human genome. These nucleosomes are highly of CTCF function. Citation: Fu Y, Sinha M, Peterson CL, Weng Z (2008) The Insulator Binding Protein CTCF

  2. Radiative Heat Transfer Analysis of Fibrous Insulation Materials Using the ZonalGEF Method

    E-Print Network [OSTI]

    Yuen, Walter W.

    Radiative Heat Transfer Analysis of Fibrous Insulation Materials Using the Zonal­GEF Method Walter to analyze radiative heat transfer in high porosity insulation materials which have a large scattering for LI900, a material used in the insulation tile for the space shuttle. Comparisons are presented

  3. Electrical insulator assembly with oxygen permeation barrier

    DOE Patents [OSTI]

    Van Der Beck, R.R.; Bond, J.A.

    1994-03-29T23:59:59.000Z

    A high-voltage electrical insulator for electrically insulating a thermoelectric module in a spacecraft from a niobium-1% zirconium alloy wall of a heat exchanger filled with liquid lithium while providing good thermal conductivity between the heat exchanger and the thermoelectric module. The insulator has a single crystal alumina layer (SxAl[sub 2]O[sub 3], sapphire) with a niobium foil layer bonded thereto on the surface of the alumina crystal facing the heat exchanger wall, and a molybdenum layer bonded to the niobium layer to act as an oxygen permeation barrier to preclude the oxygen depleting effects of the lithium from causing undesirable niobium-aluminum intermetallic layers near the alumina-niobium interface. 3 figures.

  4. Science and technology of building seals, sealants, glazing, and waterproofing: Seventh volume

    SciTech Connect (OSTI)

    Klosowski, J.M. [ed.

    1998-12-31T23:59:59.000Z

    This book captures papers from the Charles J. Parise Seventh Symposium on the Science and Technology of Building Seals. Sealants, Glazing, and Waterproofing. The overriding theme behind the papers is durability. This topic is fundamental to all users and specifiers of sealants. The first set of papers in this book addresses the topic of stress and fatigue. Joint designs vary from the square section to exaggerated hour-glass shapes. The joint designs are factors in the longevity of a sealant in the joint. The available work on accelerated weathering tests and how that relates to the damage caused by real weathering is summarized. Acrylic latex sealants can come in many qualities and some can be formulated to have properties that approach and in some cases match some of the chemically curing sealants. The unique sealant applications in roofs and doing the old fashion listing of the performance needed for each application is addressed. Destruction of a joint can be more than a failed sealant. It can be a fine sealant in a joint that is picked clean by birds. Destruction of weather protection offered by sealant, the diagnosis of the cause and solutions, especially in EIFS systems, was discussed in several papers. The esthetic concerns of fluid migration from sealants and sealant staining potential were addressed. Relative to sealant testing, the paper of work done at V.P.I. on adhesion testing is a landmark paper. Papers on finite element analysis are presented. These show where the stress concentration starts and maximizes in various joint designs and provides the basis for better joint design and better joint geometry. There is a concluding series of papers that address the adhesion of waterproofing membranes; firestopping from a latex viewpoint; polysulfide sealants for chemical containment; and a final paper looks at the myriad of places sealants are used in modern buildings and spaceframe structures.

  5. Compact vacuum insulation

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1993-01-01T23:59:59.000Z

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially "point" or "line" contacts with the metal wall sheets. In the case of monolithic spacers that form "line" contacts, two such spacers with the line contacts running perpendicular to each other form effectively "point" contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.

  6. Compact vacuum insulation embodiments

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1992-01-01T23:59:59.000Z

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially "point" or "line" contacts with the metal wall sheets. In the case of monolithic spacers that form "line" contacts, two such spacers with the line contacts running perpendicular to each other form effectively "point" contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.

  7. Compact vacuum insulation embodiments

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1992-04-28T23:59:59.000Z

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially point' or line' contacts with the metal wall sheets. In the case of monolithic spacers that form line' contacts, two such spacers with the line contacts running perpendicular to each other form effectively point' contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included. 26 figs.

  8. Process for forming transparent aerogel insulating arrays

    DOE Patents [OSTI]

    Tewari, Param H. (Milpitas, CA); Hunt, Arlon J. (Oakland, CA)

    1986-01-01T23:59:59.000Z

    An improved supercritical drying process for forming transparent silica aerogel arrays is described. The process is of the type utilizing the steps of hydrolyzing and condensing aloxides to form alcogels. A subsequent step removes the alcohol to form aerogels. The improvement includes the additional step, after alcogels are formed, of substituting a solvent, such as CO.sub.2, for the alcohol in the alcogels, the solvent having a critical temperature less than the critical temperature of the alcohol. The resulting gels are dried at a supercritical temperature for the selected solvent, such as CO.sub.2, to thereby provide a transparent aerogel array within a substantially reduced (days-to-hours) time period. The supercritical drying occurs at about 40.degree. C. instead of at about 270.degree. C. The improved process provides increased yields of large scale, structurally sound arrays. The transparent aerogel array, formed in sheets or slabs, as made in accordance with the improved process, can replace the air gap within a double glazed window, for example, to provide a substantial reduction in heat transfer. The thus formed transparent aerogel arrays may also be utilized, for example, in windows of refrigerators and ovens, or in the walls and doors thereof or as the active material in detectors for analyzing high energy elementry particles or cosmic rays.

  9. Process for forming transparent aerogel insulating arrays

    DOE Patents [OSTI]

    Tewari, P.H.; Hunt, A.J.

    1985-09-04T23:59:59.000Z

    An improved supercritical drying process for forming transparent silica aerogel arrays is described. The process is of the type utilizing the steps of hydrolyzing and condensing aloxides to form alcogels. A subsequent step removes the alcohol to form aerogels. The improvement includes the additional step, after alcogels are formed, of substituting a solvent, such as CO/sub 2/, for the alcohol in the alcogels, the solvent having a critical temperature less than the critical temperature of the alcohol. The resulting gels are dried at a supercritical temperature for the selected solvent, such as CO/sub 2/, to thereby provide a transparent aerogel array within a substantially reduced (days-to-hours) time period. The supercritical drying occurs at about 40/sup 0/C instead of at about 270/sup 0/C. The improved process provides increased yields of large scale, structurally sound arrays. The transparent aerogel array, formed in sheets or slabs, as made in accordance with the improved process, can replace the air gap within a double glazed window, for example, to provide a substantial reduction in heat transfer. The thus formed transparent aerogel arrays may also be utilized, for example, in windows of refrigerators and ovens, or in the walls and doors thereof or as the active material in detectors for analyzing high energy elementary particles or cosmic rays.

  10. 2D Dirac Materials: From Graphene to Topological Insulators

    E-Print Network [OSTI]

    Teweldebrhan, Desalegne Bekuretsion

    2011-01-01T23:59:59.000Z

    2D Topological Insulators. . . . . . . . . . . . . . . . .structure for a topological insulator. The Dirac cone fallsband structure for topological insulators. With the Fermi

  11. On the origin of the two-dimensional electron gas at AlGaN/GaN heterojunctions and its influence on recessed-gate metal-insulator-semiconductor high electron mobility transistors

    SciTech Connect (OSTI)

    Bakeroot, B., E-mail: Benoit.Bakeroot@elis.ugent.be [Centre for Microsystems Technology (CMST), imec and Ghent University, Technologiepark 914a, 9052 Gent (Belgium); You, S.; Van Hove, M.; De Jaeger, B.; Geens, K.; Stoffels, S.; Decoutere, S. [imec, Kapeldreef 75, 3001 Leuven (Belgium); Wu, T.-L.; Hu, J. [imec, Kapeldreef 75, 3001 Leuven (Belgium); Department of Electrical Engineering, KU Leuven, 3001 Leuven (Belgium)

    2014-10-07T23:59:59.000Z

    It is commonly accepted that interface states at the passivation surface of AlGaN/GaN heterostructures play an important role in the formation of the 2DEG density. Several interface state models are cited throughout literature, some with discrete levels, others with different kinds of distributions, or a combination of both. The purpose of this article is to compare the existing interface state models with both direct and indirect measurements of these interface states from literature (e.g., through the hysteresis of transfer characteristics of Metal-Insulator-Semiconductor High Electron Mobility Transistors (MISHEMTs) employing such an interface in the gate region) and Technology Computer Aided Design (TCAD) simulations of 2DEG densities as a function of the AlGaN thickness. The discrepancies between those measurements and TCAD simulations (also those commonly found in literature) are discussed. Then, an alternative model inspired by the Disorder Induced Gap State model for compound semiconductors is proposed. It is shown that defining a deep border trap inside the insulator can solve these discrepancies and that this alternative model can explain the origin of the two dimensional electron gas in combination with a high-quality interface that, by definition, has a low interface state density.

  12. Interfacial Coatings for Inorganic Composite Insulation Systems

    SciTech Connect (OSTI)

    Hooker, M. W.; Fabian, P. E.; Stewart, M. W.; Grandlienard, S. D.; Kano, K. S. [Composite Technology Development, Inc., Lafayette, CO, 80026 (United States)

    2006-03-31T23:59:59.000Z

    Inorganic (ceramic) insulation materials are known to have good radiation resistance and desirable electrical and mechanical properties at cryogenic and elevated temperatures. In addition, ceramic materials can withstand the high-temperature reaction cycle used with Nb3Sn superconductor materials, allowing the insulation to be co-processed with the superconductor in a wind-and-react fabrication process. A critical aspect in the manufacture of ceramic-based insulation systems is the deposition of suitable fiber-coating materials that prevent chemical reaction of the fiber and matrix materials, and thus provide a compliant interface between the fiber and matrix, which minimizes the impact of brittle failure of the ceramic matrix. Ceramic insulation produced with CTD-FI-202 fiber interfaces have been found to exhibit very high shear and compressive strengths. However, this material is costly to produce. Thus, the goal of the present work is to evaluate alternative, lower-cost materials and processes. A variety of oxide and polyimide coatings were evaluated, and one commercially available polyimide coating has been shown to provide some improvement as compared to uncoated and de-sized S2 glass.

  13. Buildings sector demand-side efficiency technology summaries

    SciTech Connect (OSTI)

    Koomey, J.G.; Johnson, F.X.; Schuman, J. [and others

    1994-03-01T23:59:59.000Z

    This report provides descriptions of the following energy efficiency technologies: energy management systems; electronic fluorescent ballasts; compact fluorescent lamps; lighting controls; room air conditioners; high albedo materials, coatings and paints; solar domestic water heaters; heat pump water heaters; energy-efficient motors; adjustable-speed drives; energy-efficient refrigerators; daylight control glazing; insulating glazing; solar control glazing; switchable glazing; tree planting; and advanced insulation. For each technology, the report provides a description of performance characteristics, consumer utility, development status, technology standards, equipment cost, installation, maintenance, conservation programs, and environmental impacts.

  14. Thermal insulations using vacuum panels

    DOE Patents [OSTI]

    Glicksman, Leon R. (Lynnfield, MA); Burke, Melissa S. (Pittsburgh, PA)

    1991-07-16T23:59:59.000Z

    Thermal insulation vacuum panels are formed of an inner core of compressed low thermal conductivity powders enclosed by a ceramic/glass envelope evaluated to a low pressure.

  15. Using fiberglass volumes for VPI of superconductive magnetic systems’ insulation

    SciTech Connect (OSTI)

    Andreev, I. S.; Bezrukov, A. A.; Pischugin, A. B. [Sredne-Nevskiy Shipyard (SNSZ), 10 Zavodskaya str., c. Pontonniy, Saint-Petersburg (Russian Federation); Bursikov, A. S.; Klimchenko, Y. A.; Marushin, E. L.; Mednikov, A. A.; Rodin, I. Y.; Stepanov, D. B. [The D.V. Efremov Scientific Research Institute of Electrophysical Apparatus (NIIEFA), 3 Doroga na Metallostroy, Metallostroy, Saint-Petersburg (Russian Federation)

    2014-01-29T23:59:59.000Z

    The paper describes the method of manufacturing fiberglass molds for vacuum pressure impregnation (VPI) of high-voltage insulation of superconductive magnetic systems (SMS) with epoxidian hot-setting compounds. The basic advantages of using such vacuum volumes are improved quality of insulation impregnation in complex-shaped areas, and considerable cost-saving of preparing VPI of large-sized components due to dispensing with the stage of fabricating a metal impregnating volume. Such fiberglass vacuum molds were used for VPI of high-voltage insulation samples of an ITER reactor’s PF1 poloidal coil. Electric insulation of these samples has successfully undergone a wide range of high-voltage and mechanical tests at room and cryogenic temperatures. Some results of the tests are also given in this paper.

  16. Analysis and testing of multilayer and aerogel insulation configurations

    SciTech Connect (OSTI)

    Johnson, W L [NASA Kennedy Space Center, Kennedy Space Center, Florida; Demko, Jonathan A [ORNL; Fesmire, J. E. [NASA Kennedy Space Center, Kennedy Space Center, Florida

    2010-01-01T23:59:59.000Z

    Multilayer insulation systems that have robust operational characteristics have long been a goal of many research projects. Such thermal insulation systems may need to offer some degree of structural support and/or mechanical integrity during loss of vacuum scenarios while continuing to provide insulative value to the vessel. Aerogel-based composite blankets can be the best insulation materials in ambient pressure environments; in high vacuum, the thermal performance of aerogel improves by about one order of magnitude. Standard multilayer insulation (MLI) is typically 50% worse at ambient pressure and at soft vacuum, but as much as two or three orders of magnitude better at high vacuum. Different combinations of aerogel blanket and multilayer insulation materials have been tested at the Cryogenics Test Laboratory of NASA Kennedy Space Center. Analysis performed at Oak Ridge National Laboratory showed an importance to the relative location of the MLI and aerogel blankets. Apparent thermal conductivity testing under cryogenicvacuum conditions was performed to verify the analytical conclusion. Tests results are shown to be in agreement with the analysis which indicated that the best performance is obtained with aerogel layers located in the middle of the blanket insulation system.

  17. Superconducting Topological Insulators

    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),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security AdministrationcontrollerNanocrystalline Gallium OxideSumin KimSuperconducting Topological Insulators

  18. Superconducting ``metals'' and ``insulators'' Smitha Vishveshwara

    E-Print Network [OSTI]

    Superconducting ``metals'' and ``insulators'' Smitha Vishveshwara Department of Physics, University to the distinction between normal metals and insulators: the superconducting ``metal'' with delocalized qua- siparticle excitations and the superconducting ``insulator'' with localized quasiparticles. We describe

  19. Compact vacuum insulation

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1992-10-27T23:59:59.000Z

    Improved compact insulation panel is provided which is comprised of two adjacent metal sheets spaced close together with a plurality of spherical, or other discretely shaped, glass or ceramic beads optimally positioned between the sheets to provide support and maintain the spacing between the metal sheets when the gases there between are evacuated to form a vacuum. These spherical glass beads provide the maximum support while minimizing thermal conductance. In its preferred embodiment; these two metal sheets are textured with ribs or concave protrusions in conjunction with the glass beads to maximize the structural integrity of the panels while increasing the spacing between beads, thereby reducing the number of beads and the number of thermal conduction paths. Glass or porcelain-enameled liners in combination with the glass spacers and metal sidewalls effectively decrease thermal conductivity, and various laminates, including wood, porcelain-enameled metal, and others effectively increase the strength and insulation capabilities of the panels. Also, a metal web is provided to hold the spacers in place, and strategic grooves are shown to accommodate expansion and contraction or shaping of the panels. 35 figs.

  20. Compact vacuum insulation

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1992-01-01T23:59:59.000Z

    Improved compact insulation panel is provided which is comprised of two adjacent metal sheets spaced close together with a plurality of spherical, or other discretely shaped, glass or ceramic beads optimally positioned between the sheets to provide support and maintain the spacing between the metal sheets when the gases therebetween are evacuated to form a vacuum. These spherical glass beads provide the maximum support while minimizing thermal conductance. In its preferred embodiment; these two metal sheets are textured with ribs or concave protrusions in conjunction with the glass beads to maximize the structural integrity of the panels while increasing the spacing between beads, thereby reducing the number of beads and the number of thermal conduction paths. Glass or porcelain-enameled liners in combination with the glass spacers and metal sidewalls effectively decrease thermal conductivity, and variious laminates, including wood, porcelain-enameled metal, and others effectively increase the strength and insulation capabilities of the panels. Also, a metal web is provided to hold the spacers in place, and strategic grooves are shown to accommodate expansion and contraction or shaping of the panels.

  1. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Flipping Photoelectron Spins in Topological Insulators Print Tuesday, 23 April 2013 10:00 Inherently strange crystalline...

  2. Flipping Photoelectron Spins in Topological Insulators

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

    Flipping Photoelectron Spins in Topological Insulators Print Inherently strange crystalline materials called 3D topological insulators (TIs) are all the rage in materials science....

  3. Solar Decathlon Technology Spotlight: Structural Insulated Panels...

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

    Decathlon Technology Spotlight: Structural Insulated Panels Solar Decathlon Technology Spotlight: Structural Insulated Panels September 20, 2011 - 7:13am Addthis These structural...

  4. Types of Insulation | Department of Energy

    Energy Savers [EERE]

    -- into insulation systems that can include a variety of backings, such as kraft paper, plastic film, polyethylene bubbles, or cardboard, as well as thermal insulation materials....

  5. Aerogel Impregnated Polyurethane Piping and Duct Insulation ...

    Energy Savers [EERE]

    Aerogel Impregnated Polyurethane Piping and Duct Insulation Aerogel Impregnated Polyurethane Piping and Duct Insulation Emerging Technologies Project for the 2013 Building...

  6. Density Matrix Topological Insulators

    E-Print Network [OSTI]

    A. Rivas; O. Viyuela; M. A. Martin-Delgado

    2013-10-31T23:59:59.000Z

    Thermal noise can destroy topological insulators (TI). However we demonstrate how TIs can be made stable in dissipative systems. To that aim, we introduce the notion of band Liouvillian as the dissipative counterpart of band Hamiltonian, and show a method to evaluate the topological order of its steady state. This is based on a generalization of the Chern number valid for general mixed states (referred to as density matrix Chern value), which witnesses topological order in a system coupled to external noise. Additionally, we study its relation with the electrical conductivity at finite temperature, which is not a topological property. Nonetheless, the density matrix Chern value represents the part of the conductivity which is topological due to the presence of quantum mixed edge states at finite temperature. To make our formalism concrete, we apply these concepts to the two-dimensional Haldane model in the presence of thermal dissipation, but our results hold for arbitrary dimensions and density matrices.

  7. Multiple layer insulation cover

    DOE Patents [OSTI]

    Farrell, James J. (Livingston Manor, NY); Donohoe, Anthony J. (Ovid, NY)

    1981-11-03T23:59:59.000Z

    A multiple layer insulation cover for preventing heat loss in, for example, a greenhouse, is disclosed. The cover is comprised of spaced layers of thin foil covered fabric separated from each other by air spaces. The spacing is accomplished by the inflation of spaced air bladders which are integrally formed in the cover and to which the layers of the cover are secured. The bladders are inflated after the cover has been deployed in its intended use to separate the layers of the foil material. The sizes of the material layers are selected to compensate for sagging across the width of the cover so that the desired spacing is uniformly maintained when the cover has been deployed. The bladders are deflated as the cover is stored thereby expediting the storage process and reducing the amount of storage space required.

  8. Insulation Mechanisms of in vivo Biomolecular Circuits Kayzad S. Nilgiriwala, Phillip M. Rivera and Domitilla Del Vecchio

    E-Print Network [OSTI]

    Del Vecchio, Domitilla

    Insulation Mechanisms of in vivo Biomolecular Circuits Kayzad S. Nilgiriwala, Phillip M. Rivera,2,3). It has been theoretically shown that a system can be insulated from retroactivity by using high gain, effectively insulating the cycle from retroactivity by downstream DNA targets. Hence, phosphorylation cycles

  9. Design and analysis of SMES-ETM electrical insulation

    SciTech Connect (OSTI)

    Wu, J.L.; Roach, J.F.; Johnson, D.C.; Dederer, J.T.; Singh, S.K.; Hackworth, D.T. [Westinghouse Science & Technology Center, Pittsburgh, PA (United States)

    1994-12-31T23:59:59.000Z

    The mechanical design and the electrical field analysis of the Ebasco/Westinghouse SMES-ETM coil electrical insulation system are presented. The electrical insulation design of the coil includes the turn to turn, layer to layer, and between the coil to the wall of the liquid helium vessel of the cryostat. A finite element analysis code (WEMAP) was used to obtain detailed electrical field plots of the high electrically stressed regions of the coil. These analytical results were used in conjunction with the experimental data of dielectric breakdown, available in the literature or obtained by in-house testing, to determine the optimum configuration and materials of the insulation spacers. An adequate design safety factor between the insulation capability and the maximum operating electrical stress was adopted to ensure the design integrity under all operating conditions and to allow for the uncertainties of the experimental dielectric breakdown data.

  10. Identification of building applications for a variable-conductance insulation

    SciTech Connect (OSTI)

    Potter, T.F. [National Renewable Energy Lab., Golden, CO (United States); Tuluca, A. [Winter (Steven) Associates, Inc., New York, NY (United States)

    1992-07-01T23:59:59.000Z

    Recent experiments have confirmed the feasibility of controllable, reversible disabling of a vacuum insulation panel, which may result in the development of energy-efficient building envelope components. These components could extend the managed energy exchange through the building envelope from about 30% (typical with fenestration systems in commercial buildings), to as much as 90% of the gross wall and roof areas. Further investigation will be required to optimized the thermal response and the magnitude of the R-value swing (from a difference between insulating and conducting insulating values of 4 to as high as a factor of 100). The potential for energy reduction by using the variable-conductance insulation in the building envelope is discussed, and other potential building applications are mentioned.

  11. Ceramic electrical insulation for electrical coils, transformers, and magnets

    DOE Patents [OSTI]

    Rice, John A. (Longmont, CO); Hazelton, Craig S. (Lafayette, CO); Fabian, Paul E. (Broomfield, CO)

    2002-01-01T23:59:59.000Z

    A high temperature electrical insulation is described, which is suitable for electrical windings for any number of applications. The inventive insulation comprises a cured preceramic polymer resin, which is preferably a polysiloxane resin. A method for insulating electrical windings, which are intended for use in high temperature environments, such as superconductors and the like, advantageously comprises the steps of, first, applying a preceramic polymer layer to a conductor core, to function as an insulation layer, and second, curing the preceramic polymer layer. The conductor core preferably comprises a metallic wire, which may be wound into a coil. In the preferred method, the applying step comprises a step of wrapping the conductor core with a sleeve or tape of glass or ceramic fabric which has been impregnated by a preceramic polymer resin. The inventive insulation system allows conducting coils and magnets to be fabricated using existing processing equipment, and maximizes the mechanical and thermal performance at both elevated and cryogenic temperatures. It also permits co-processing of the wire and the insulation to increase production efficiencies and reduce overall costs, while still remarkably enhancing performance.

  12. Tunable Dirac Fermion Dynamics in Topological Insulators

    E-Print Network [OSTI]

    Wang, Wei Hua

    Tunable Dirac Fermion Dynamics in Topological Insulators Chaoyu Chen1 , Zhuojin Xie1 , Ya Feng1, Beijing 100190, China. Three-dimensional topological insulators are characterized by insulating bulk state topological insulators. We have directly revealed signatures of the electron-phonon coupling and found

  13. STATE OF CALIFORNIA INSULATION STAGE CHECKLIST

    E-Print Network [OSTI]

    STATE OF CALIFORNIA INSULATION STAGE CHECKLIST CEC-CF-6R-ENV-22 (Revised 05/12) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-ENV-22 Quality Insulation Installation (QII) - Insulation Stage be insulated in a manner that resists thermal bridging of the assembly separating conditioned from

  14. Chromatin insulators: lessons from the fly

    E-Print Network [OSTI]

    Corces, Victor G.

    Chromatin insulators: lessons from the fly B.V.Gurudatta and Victor G.Corces Abstract Chromatin insulators are DNA^protein complexes with broad functions in nuclear biology. Drosophila has at least five different types of insulators; recent results suggest that these different insulators share some components

  15. Insulation products promote thermal efficiency

    SciTech Connect (OSTI)

    Chalmers, R.

    1985-04-01T23:59:59.000Z

    The judicious use of thermal insulation products in non-residential buildings can provide a number of advantages including increased energy efficiency, lower first costs (by avoiding overside HVAC systems), improved fire safety and better acoustics. Thermal insulation products are those products which retard the flow of heat energy. Materials include glass, plastics, and organic materials such as wood fibers, vermiculite and perlite. Forms range from the familiar batts and blankets of glass fibers to foamed plastic, rigid boards, losse fill and systems combining two or more products, such as polystyrene boards covered with insulating plaster. The R values of selected insulation materials with a cost/sq. ft. of each material at R 10 are given. Costs cover both the material and installation and may vary depending on local conditions.

  16. Correlation effects on topological insulator

    E-Print Network [OSTI]

    Xiong-Jun Liu; Yang Liu; Xin Liu

    2010-11-24T23:59:59.000Z

    The strong correlation effects on topological insulator are studied in a two-sublattice system with an onsite single-particle energy difference $\\Delta$ between two sublattices. At $\\Delta=0$, increasing the onsite interaction strength $U$ drives the transition from the quantum spin Hall insulating state to the non-topological antiferromagnetic Mott-insulating (AFMI) state. When $\\Delta$ is larger than a certain value, a topologically trivial band insulator or AFMI at small values of $U$ may change into a quantum anomalous Hall state with antiferromagnetic ordering at intermediate values of $U$. Further increasing $U$ drives the system back into the topologically trivial state of AFMI. The corresponding phenomena is observable in the solid state and cold atom systems. We also propose a scheme to realize and detect these effects in cold atom systems.

  17. Measure Guideline: Basement Insulation Basics

    SciTech Connect (OSTI)

    Aldrich, R.; Mantha, P.; Puttagunta, S.

    2012-10-01T23:59:59.000Z

    This guideline is intended to describe good practices for insulating basements in new and existing homes, and is intended to be a practical resources for building contractors, designers, and also to homeowners.

  18. The Facility The Propellants North Administrative and Maintenance

    E-Print Network [OSTI]

    and Maintenance Facility Inside Propellants North is window glazing and framing from the iconic firing rooms with energy recovery technology · Highly insulated roof and walls · Lighting fixtures with smart lighting glazing and framing · Reclaimed and processed waste concrete from Kennedy's demolition projects

  19. Variable pressure thermal insulating jacket

    DOE Patents [OSTI]

    Nelson, P.A.; Malecha, R.F.; Chilenskas, A.A.

    1994-09-20T23:59:59.000Z

    A device for controlled insulation of a thermal device is disclosed. The device includes a thermal jacket with a closed volume able to be evacuated to form an insulating jacket around the thermal source. A getter material is in communication with the closed volume of the thermal jacket. The getter material can absorb and desorb a control gas to control gas pressure in the volume of the thermal jacket to control thermal conductivity in the thermal jacket. 10 figs.

  20. Cost-Effective Cable Insulation: Nanoclay Reinforced Ethylene-Propylene-Rubber for Low-Cost HVDC Cabling

    SciTech Connect (OSTI)

    None

    2012-02-24T23:59:59.000Z

    GENI Project: GE is developing new, low-cost insulation for high-voltage direct current (HVDC) electricity transmission cables. The current material used to insulate HVDC transmission cables is very expensive and can account for as much as 1/3 of the total cost of a high-voltage transmission system. GE is embedding nanomaterials into specialty rubber to create its insulation. Not only are these materials less expensive than those used in conventional HVDC insulation, but also they will help suppress excess charge accumulation. The excess charge left behind on a cable poses a major challenge for high-voltage insulation—if it’s not kept to a low level, it could ultimately lead the insulation to fail. GE’s low-cost insulation is compatible with existing U.S. cable manufacturing processes, further enhancing its cost effectiveness.

  1. Surprising Control over Photoelectrons from a Topological Insulator

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

    over Photoelectrons from a Topological Insulator Print Tuesday, 12 March 2013 00:00 Topological insulators are insulators in the bulk but metals on the surface, and the...

  2. GROUND PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

    is WIUUTEO GROUND PLANE INSULATION FAILURE IN THE FIRST TPCOn August 27, 1980, an insulation failure occurred dt-ringby a failure uf ground plane insulation. ACKNOWLEDGMENTS The

  3. Typical Clothing Ensemble Insulation Levels for Sixteen Body Parts

    E-Print Network [OSTI]

    Lee, Juyoun; Zhang, Hui; Arens, Edward

    2013-01-01T23:59:59.000Z

    Thermal Comfort.1994 CLO Insulation Levels For Sixteen Bodya mesh arm chair whose insulation level was measured. FigureExperimental Conditions. CLO Insulation Levels For Sixteen

  4. Vertically aligned gas-insulated transmission line having particle traps at the inner conductor

    DOE Patents [OSTI]

    Dale, Steinar J. (Monroeville, PA)

    1984-01-01T23:59:59.000Z

    Gas insulated electrical apparatus having first and second conductors separated by an insulating support within an insulating gas environment, and particle traps disposed along the surface of the high potential conductor for trapping and inactivating foreign particles which may be present within the insulating gas medium. Several embodiments of the invention were developed which are particularly suited for vertically aligned gas insulated transmission lines. The particle traps are grooves or cavities formed into the walls of the tubular inner conductor, without extending into the hollow portion of the conductor. In other embodiments, the traps are appendages or insert flanges extending from the inner conductor, with the insulator supports contacting the appendages instead of the inner conductor.

  5. Electrical Insulation Paper and Its Physical Properties at Cryogenic Temperatures

    SciTech Connect (OSTI)

    Tuncer, Enis [ORNL] [ORNL; Polyzos, Georgios [ORNL] [ORNL; Sauers, Isidor [ORNL] [ORNL; James, David Randy [ORNL] [ORNL

    2011-01-01T23:59:59.000Z

    Paper is widely used in various engineering applications due to its physical properties and ease of manufacture. As a result paper has been selected or designed as an electrical insulation material for parts and components in high voltage technology. In the current study we select a paper employed in conventional transformers as the electrical insulation material. The potential of this paper is investigated at cryogenic temperatures to determine its physical properties for high temperature superconducting power applications. Dielectric measurements were performed using impedance spectroscopy at a constant frequency. Dielectric breakdown tests were performed on samples at 77 K using a liquid nitrogen bath.

  6. Approximating Metal-Insulator Transitions

    E-Print Network [OSTI]

    C. Danieli; K. Rayanov; B. Pavlov; G. Martin; S. Flach

    2014-05-06T23:59:59.000Z

    We consider quantum wave propagation in one-dimensional quasiperiodic lattices. We propose an iterative construction of quasiperiodic potentials from sequences of potentials with increasing spatial period. At each finite iteration step the eigenstates reflect the properties of the limiting quasiperiodic potential properties up to a controlled maximum system size. We then observe approximate metal-insulator transitions (MIT) at the finite iteration steps. We also report evidence on mobility edges which are at variance to the celebrated Aubry-Andre model. The dynamics near the MIT shows a critical slowing down of the ballistic group velocity in the metallic phase similar to the divergence of the localization length in the insulating phase.

  7. STATE OF CALIFORNIA ENVELOPE INSULATION; ROOFING; FENESTRATION

    E-Print Network [OSTI]

    STATE OF CALIFORNIA ENVELOPE ­ INSULATION; ROOFING; FENESTRATION CEC-CF-6R-ENV-01 (Revised 08/09) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-ENV-01 Envelope ­ Insulation; Roofing:__________________________________ Brand Name:_______________________________ Thickness (inches):_________________________ Thermal

  8. Degradation of Structural Alloys Under Thermal Insulation

    E-Print Network [OSTI]

    McIntyre, D. R.

    1984-01-01T23:59:59.000Z

    Wet thermal insulation may actively degrade steel and stainless steel structures by general corrosion or stress-corrosion cracking. Two different mechanisms of water ingress into insulation are discussed; flooding from external sources...

  9. Insulation board and process of making

    DOE Patents [OSTI]

    Nowobilski, Jeffert J. (Orchard Park, NY); Owens, William J. (Kenmore, NY)

    1985-01-01T23:59:59.000Z

    Insulation board capable of bearing a load without significant loss of insulating capacity due to compression, produced by a method wherein the board is made in compliance with specified conditions of time, temperature and pressure.

  10. Metal-Insulator Photocathode Heterojunction for Directed Electron...

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

    Insulator Photocathode Heterojunction for Directed Electron Emission. Metal-Insulator Photocathode Heterojunction for Directed Electron Emission. Abstract: New photocathode...

  11. Dynamics of Dirac Fermions in Topological Insulators

    E-Print Network [OSTI]

    Arnold, Anton

    Dynamics of Dirac Fermions in Topological Insulators R. Hammer1 , C. Ertler1 , W. P¨otz1 , and A.hammer@uni-graz.at Abstract We study the coherent dynamics of Dirac fermions on the surface of topological insulators in one topological insulators (TI) we investigate theoretically the dynamics of Dirac fermion wave packets on their 2

  12. A Holographic Fractional Topological Insulator

    E-Print Network [OSTI]

    Carlos Hoyos-Badajoz; Kristan Jensen; Andreas Karch

    2010-07-19T23:59:59.000Z

    We give a holographic realization of the recently proposed low energy effective action describing a fractional topological insulator. In particular we verify that the surface of this hypothetical material supports a fractional quantum Hall current corresponding to half that of a Laughlin state.

  13. Vacuum-insulated catalytic converter

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO)

    2001-01-01T23:59:59.000Z

    A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

  14. Theory of the Anomalous Hall Effect in the Insulating Regime

    E-Print Network [OSTI]

    Liu, Xiongjun

    2012-10-19T23:59:59.000Z

    , the AHE was revived in recent years by generating many new understandings and phenomena, e.g. spin-Hall effect, topological insulators. The phase diagram of the AHE was shown recently to exhibit three distinct regions: a skew scattering region in the high...

  15. Microstructures and properties of laser-glazed plasma-sprayed ZrO{sub 2}-YO{sub 1.5}/Ni-22Cr-10Al-1Y thermal barrier coatings

    SciTech Connect (OSTI)

    Tsai, H.L.; Tsai, P.C. [National Taiwan Inst. of Tech., Taipei (Taiwan, Province of China). Dept. of Mechanical Engineering and Technology

    1995-12-01T23:59:59.000Z

    Thermal barrier coatings (TBCs) consisting of two layers with various yttria contents (ZrO{sub 2}-YO{sub 1.5}/Ni-22Cr-10Al-1Y) were plasma sprayed, and parts of the various specimens were glazed by using a pulsed CO{sub 2} laser. All the specimens were then subjected to furnace thermal cycling tests at 1,100 C; the effect of laser glazing on the durability and failure mechanism of the TBCs was then evaluated. From these results, two models were developed to show the failure mechanism of as-sprayed and laser-glazed TBCs: model A, which is thermal-stress dominant, and model V, which is oxidation-stress dominant. For top coats containing cubic phase, cubic and monoclinic phases, or tetragonal and a relatively larger amount of monoclinic phases, whose degradation is thermal-stress dominant, laser glazing improved the durability of TBCs by a factor of about 2 to 6. Segmented cracks that occurred during glazing proved beneficial for accommodating thermal stress and raising the tolerance to oxidation, which resulted in a higher durability. Thermal barrier coatings with top coats containing tetragonal phase had the highest durability. Degradation of such TBCs resulted mainly from oxidation of the bond coats. For top coats with a greater amount of monoclinic phase, thermal mismatch stress occurred during cooling and detrimentally affected durability.

  16. Variably insulating portable heater/cooler

    DOE Patents [OSTI]

    Potter, Thomas F. (Denver, CO)

    1998-01-01T23:59:59.000Z

    A compact vacuum insulation panel comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning "on" and "off" the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls.

  17. Variably insulating portable heater/cooler

    DOE Patents [OSTI]

    Potter, T.F.

    1998-09-29T23:59:59.000Z

    A compact vacuum insulation panel is described comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning ``on`` and ``off`` the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls. 25 figs.

  18. Material-controlled dynamic vacuum insulation

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1996-10-08T23:59:59.000Z

    A compact vacuum insulation panel is described comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning ``on`` and ``off`` the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls. 25 figs.

  19. Material-controlled dynamic vacuum insulation

    DOE Patents [OSTI]

    Benson, David K. (14154 W. First Dr., Golden, CO 80401); Potter, Thomas F. (515 S. Magnolia La., Denver, CO 80224)

    1996-10-08T23:59:59.000Z

    A compact vacuum insulation panel comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber includes apparatus and methods for enabling and disabling, or turning "on" and "off" the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls.

  20. Radiation-controlled dynamic vacuum insulation

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1995-07-18T23:59:59.000Z

    A compact vacuum insulation panel is described comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber that includes apparatus and methods for enabling and disabling, or turning ``on`` and ``off`` the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls. 25 figs.

  1. Radiation-controlled dynamic vacuum insulation

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1995-01-01T23:59:59.000Z

    A compact vacuum insulation panel comprising a chamber enclosed by two sheets of metal, glass-like spaces disposed in the chamber between the sidewalls, and a high-grade vacuum in the chamber that includes apparatus and methods for enabling and disabling, or turning "on" and "off" the thermal insulating capability of the panel. One type of enabling and disabling apparatus and method includes a metal hydride for releasing hydrogen gas into the chamber in response to heat, and a hydrogen grate between the metal hydride and the chamber for selectively preventing and allowing return of the hydrogen gas to the metal hydride. Another type of enabling and disabling apparatus and method includes a variable emissivity coating on the sheets of metal in which the emissivity is controllably variable by heat or electricity. Still another type of enabling and disabling apparatus and method includes metal-to-metal contact devices that can be actuated to establish or break metal-to-metal heat paths or thermal short circuits between the metal sidewalls.

  2. Insulation assembly for electric machine

    SciTech Connect (OSTI)

    Rhoads, Frederick W.; Titmuss, David F.; Parish, Harold; Campbell, John D.

    2013-10-15T23:59:59.000Z

    An insulation assembly is provided that includes a generally annularly-shaped main body and at least two spaced-apart fingers extending radially inwards from the main body. The spaced-apart fingers define a gap between the fingers. A slot liner may be inserted within the gap. The main body may include a plurality of circumferentially distributed segments. Each one of the plurality of segments may be operatively connected to another of the plurality of segments to form the continuous main body. The slot liner may be formed as a single extruded piece defining a plurality of cavities. A plurality of conductors (extendable from the stator assembly) may be axially inserted within a respective one of the plurality of cavities. The insulation assembly electrically isolates the conductors in the electric motor from the stator stack and from other conductors.

  3. Metal-insulator transition in Na{sub x}WO{sub 3}: Photoemission spectromicroscopy study

    SciTech Connect (OSTI)

    Paul, Sanhita, E-mail: raj@iiserkol.ac.in; Ghosh, Anirudha, E-mail: raj@iiserkol.ac.in; Raj, Satyabrata, E-mail: raj@iiserkol.ac.in [Department of Physical Sciences, Indian Institute of Science Education and Research - Kolkata, Mohanpur Campus, Nadia -741252, West Bengal (India)

    2014-04-24T23:59:59.000Z

    We have investigated the validity of percolation model, which is quite often invoked to explain the metal-insulator transition in sodium tungsten bronzes, Na{sub x}WO{sub 3} by photoelectron spectromicroscopy. The spatially resolved direct spectromicroscopic probing on both the insulating and metallic phases of high quality single crystals of Na{sub x}WO{sub 3} reveals the absence of any microscopic inhomogeneities embedded in the system within the experimental limit. Neither any metallic domains in the insulating host nor any insulating domains in the metallic host have been found to support the validity of percolation model to explain the metal-insulator transition in Na{sub x}WO{sub 3}.

  4. Impact of Thermally Insulated Floors

    E-Print Network [OSTI]

    Alghimlas, F.; Omar, E. A.

    2004-01-01T23:59:59.000Z

    Measures for their Implementation in Kuwait (DOE-1), Volume 2: Development of Typical Meteorological Year for Kuwait (Element 2, Sub-element 6). Kuwait Institute for Scientific Research Report No. KISR5857, Kuwait. 2000. ... Department of Kuwait Institute for Scientific Research for revision of the code this paper analyzes the effect of using un-insulated floors on the peak cooling demand and energy consumption of a middle income residential private villa and a one- bedroom...

  5. Topological Insulators at Room Temperature

    SciTech Connect (OSTI)

    Zhang, Haijun; /Beijing, Inst. Phys.; Liu, Chao-Xing; /Tsinghua U., Beijing; Qi, Xiao-Liang; /Stanford U., Phys. Dept.; Dai, Xi; Fang, Zhong; /Beijing, Inst. Phys.; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

    2010-03-25T23:59:59.000Z

    Topological insulators are new states of quantum matter with surface states protected by the time-reversal symmetry. In this work, we perform first-principle electronic structure calculations for Sb{sub 2}Te{sub 3}, Sb{sub 2}Se{sub 3}, Bi{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3} crystals. Our calculations predict that Sb{sub 2}Te{sub 3}, Bi{sub 2}T e{sub 3} and Bi{sub 2}Se{sub 3} are topological insulators, while Sb{sub 2}Se{sub 3} is not. In particular, Bi{sub 2}Se{sub 3} has a topologically non-trivial energy gap of 0.3eV , suitable for room temperature applications. We present a simple and unified continuum model which captures the salient topological features of this class of materials. These topological insulators have robust surface states consisting of a single Dirac cone at the {Lambda} point.

  6. T-Duality of Topological Insulators

    E-Print Network [OSTI]

    Varghese Mathai; Guo Chuan Thiang

    2015-04-08T23:59:59.000Z

    Topological insulators and D-brane charges in string theory can both be classified by the same family of groups. In this letter, we extend this connection via a geometric transform, giving a novel duality of topological insulators which can be viewed as a condensed matter analog of T-duality in string theory. For 2D Chern insulators, this duality exchanges the rank and Chern number of the valence bands.

  7. Floating insulated conductors for heating subsurface formations

    DOE Patents [OSTI]

    Burns, David; Goodwin, Charles R.

    2014-07-29T23:59:59.000Z

    A heating system for a subsurface formation includes a conduit located in a first opening in the subsurface formation. Three electrical conductors are located in the conduit. A return conductor is located inside the conduit. The return conductor is electrically coupled to the ends of the electrical conductors distal from the surface of the formation. Insulation is located inside the conduit. The insulation electrically insulates the three electrical conductors, the return conductor, and the conduit from each other.

  8. Insulator damage endangers public, power reliability; ratepayers...

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

    Insulator-damage-endangers-public-power-reliability-ratepayers-foot-repair-bill Sign In About | Careers | Contact | Investors | bpa.gov Search News & Us Expand News & Us...

  9. How Much Insulation is Too Much?

    Broader source: Energy.gov [DOE]

    This presentation was given at the Summer 2012 DOE Building America meeting on July 25, 2012, and addressed the question "How much insulation is too much?"

  10. Farmers RECC- Residential Insulation Rebate Program

    Broader source: Energy.gov [DOE]

    The Farmers Rural Electric Cooperative (RECC) Button-Up Program provides free energy audits and rebates for insulation upgrades to its residential customers. Farmers RECC's energy advisor will...

  11. Thermal insulation by heat resistant polymers.

    E-Print Network [OSTI]

    Ahmed, Ashraf Fathy

    2009-01-01T23:59:59.000Z

    ??Internal insulation in a solid rocket motor is a layer of heat-barrier material placed between the internal surface of the case and the propellant. The… (more)

  12. Building America Expert Meeting: Interior Insulation Retrofit...

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

    Building Science Corporation team held an Expert Meeting on Interior Insulation Retrofit of Mass Masonry Wall Assemblies on July 30, 2011, at the Westford Regency Hotel in...

  13. Insulation and Heat Treatment of Bi-2212 Wire for Wind-and-React Coils

    SciTech Connect (OSTI)

    Peter K. F. Hwang

    2007-10-22T23:59:59.000Z

    Higher Field Magnets demand higher field materials such as Bi-2212 round superconducting wire. The Bi-2212 wire manufacture process depends on the coil fabrication method and wire insulation material. Considering the wind-and-react method, the coil must unifirmly heated to the melt temperature and uniformly cooled to the solidification temperature. During heat treat cycle for tightly wound coils, the leakage melt from conductor can chemically react with insulation on the conductor and creat short turns in the coils. In this research project, conductor, insulation, and coils are made to systemically study the suitable insulation materials, coil fabrication method, and heat treatment cycles. In this phase I study, 800 meters Bi-2212 wire with 3 different insulation materials have been produced. Best insulation material has been identified after testing six small coils for insulation integrity and critical current at 4.2 K. Four larger coils (2" dia) have been also made with Bi-2212 wrapped with best insulation and with different heattreatment cycle. These coils were tested for Ic in a 6T background field and at 4.2 K. The test result shows that Ic from 4 coils are very close to short samples (1 meter) result. It demonstrates that HTS coils can be made with Bi-2212 wire with best insulation consistently. Better wire insulation, improving coil winding technique, and wire manufacture process can be used for a wide range of high field magnet application including acclerators such as Muon Collider, fusion energy research, NMR spectroscopy, MRI, and other industrial magnets.

  14. From topological insulators to superconductors and Confinement

    E-Print Network [OSTI]

    M. Cristina Diamantini; Pasquale Sodano; Carlo A. Trugenberger

    2012-02-01T23:59:59.000Z

    Topological matter in 3D is characterized by the presence of a topological BF term in its long-distance effective action. We show that, in 3D, there is another marginal term that must be added to the action in order to fully determine the physical content of the model. The quantum phase structure is governed by three parameters that drive the condensation of topological defects: the BF coupling, the electric permittivity and the magnetic permeability of the material. For intermediate levels of electric permittivity and magnetic permeability the material is a topological insulator. We predict, however, new states of matter when these parameters cross critical values: a topological superconductor when electric permittivity is increased and magnetic permeability is lowered and a charge confinement phase in the opposite case of low electric permittivity and high magnetic permeability. Synthetic topological matter may be fabricated as 3D arrays of Josephson junctions.

  15. High Performance Building Facade Solutions PIER Final Project Report

    E-Print Network [OSTI]

    Lee, Eleanor

    2011-01-01T23:59:59.000Z

    such as electrochromic glazings will have major market andsuch as electrochromic glazings will have major market andMarket Program”. These insights were summarized in a document: “Electrochromic

  16. On Holographic Insulators and Supersolids

    E-Print Network [OSTI]

    Kiritsis, Elias

    2015-01-01T23:59:59.000Z

    We obtain holographic realisations for systems that have strong similarities to Mott insulators and supersolids, after examining the ground states of Einstein-Maxwell-scalar systems. The real part of the AC conductivity has a hard gap and a discrete spectrum only. We add momentum dissipation to resolve the delta function in the conductivity due to translational invariance. We develop tools to directly calculate the Drude weight for a large class of solutions and to support our claims. Numerical RG flows are also constructed to verify that such saddle points are IR fixed points of asymptotically AdS_4 geometries.

  17. Topological insulators of bosons/spins T. Senthil (MIT)

    E-Print Network [OSTI]

    Topological insulators of bosons/spins T. Senthil (MIT) Thanks: X.-G.Wen, M.P.A. Fisher Trivial phases Eg: Band insulators, superfluids, antiferromagnets, ......... Gapped `topologically ordered phases Eg: Band insulators, superfluids, antiferromagnets, ......... Gapped `topologically ordered

  18. Classification and characterization of topological insulators and superconductors

    E-Print Network [OSTI]

    Mong, Roger

    2012-01-01T23:59:59.000Z

    Antiferromagnetic topological insulators 5.1 Z 2 topological1.3 Topological insulators in 3D . . . . . . . . . . . . .1.3.1 Strong topological insulators (STI) . . . . . 1.3.2

  19. Widespread spin polarizationeffects in photoemission from topological insulators

    E-Print Network [OSTI]

    Jozwiak, C.

    2012-01-01T23:59:59.000Z

    photoemission from topological insulators C. Jozwiak, 1, ?approach in the 3D topological insulators. [1] D. Hsieh, D.three-dimensional topological insulator Bi 2 Se 3 using a

  20. APPLIED PHYSICS REVIEWS Semi-insulating semiconductor heterostructures: Optoelectronic

    E-Print Network [OSTI]

    Nolte, David D.

    APPLIED PHYSICS REVIEWS Semi-insulating semiconductor heterostructures: Optoelectronic properties of optoelectronic properties of and uses for semi-insulating semiconductor heterostructures and thin films. The principal optical and optoelectronic properties of semi-insulating epilayers and heterostructures

  1. Low-cost exterior insulation process and structure

    DOE Patents [OSTI]

    Vohra, A.

    1999-03-02T23:59:59.000Z

    A low-cost exterior insulation process of stacking bags of insulating material against a wall and covering them with wire mesh and stucco provides a durable structure with good insulating value. 2 figs.

  2. Low-cost exterior insulation process and structure

    DOE Patents [OSTI]

    Vohra, Arun (Bethesda, MD)

    1999-01-01T23:59:59.000Z

    A low-cost exterior insulation process of stacking bags of insulating material against a wall and covering them with wire mesh and stucco provides a durable structure with good insulating value.

  3. Modular cell biology: retroactivity and insulation Domitilla Del Vecchio1,

    E-Print Network [OSTI]

    Sontag, Eduardo

    Modular cell biology: retroactivity and insulation Domitilla Del Vecchio1, *, Alexander J Ninfa2 a remarkable insulation property, due to the fast timescales of the phosphorylation and dephosphorylation: computational methods; metabolic and regulatory networks Keywords: feedback; insulation; modularity; singular

  4. Charge and spin topological insulators

    SciTech Connect (OSTI)

    Kopaev, Yu. V., E-mail: kopaev@sci.lebedev.ru; Gorbatsevich, A. A.; Belyavskii, V. I. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2011-09-15T23:59:59.000Z

    The topologically nontrivial states of matter-charge and spin topological insulators, which exhibit, respectively, properties of the integer quantum Hall effect and the quantum spin Hall effect-are discussed. The topological characteristics (invariant with respect to weak adiabatic changes in the Hamiltonian parameters) which lead to such states are considered. The model of a 2D hexagonal lattice having symmetries broken with respect to time reversal and spatial inversion which was proposed by Haldane and marked the beginning of unprecedented activity in the study of topologically nontrivial states is discussed. This model relates the microscopic nature of the symmetry breaking with respect to the time reversal to the occurrence of spontaneous orbital currents which circulate within a unit cell. Such currents become zero upon summation over the unit cell, but they may form spreading current states at the surface which are similar to the edge current states under the quantum Hall effect. The first model of spontaneous currents (exciton insulator model) is considered, and the possibility of implementing new topologically nontrivial states in this model is discussed.

  5. Comprehensive study of the metal-insulator transition in pulsed laser deposited epitaxial VO2 thin films

    E-Print Network [OSTI]

    Wu, Junqiao

    Comprehensive study of the metal-insulator transition in pulsed laser deposited epitaxial VO2 thin properties of high-quality VO2 thin films across its metal-insulator phase transition. Detailed x-ray deposition,9 sol-gel deriving,10 sputtering,11 and pulsed laser deposition,12 the study of VO2 is reviving

  6. Uniform insulation applied-B ion diode

    DOE Patents [OSTI]

    Seidel, David B. (Albuquerque, NM); Slutz, Stephen A. (Albuquerque, NM)

    1988-01-01T23:59:59.000Z

    An applied-B field extraction ion diode has uniform insulation over an anode surface for increased efficiency. When the uniform insulation is accomplished with anode coils, and a charge-exchange foil is properly placed, the ions may be focused at a point on the z axis.

  7. Kingspan Insulated Panels: Order (2013-CE-5353)

    Broader source: Energy.gov [DOE]

    DOE ordered Kingspan Insulated Panels, Inc. to pay a $8,000 civil penalty after finding Kingspan Insulated Panels had failed to certify that any basic models of walk-in cooler and freezer components comply with the applicable energy conservation standards.

  8. Measurement of Exterior Foundation Insulation to Assess Durability in Energy-Saving Performance

    SciTech Connect (OSTI)

    Kehrer, Manfred [ORNL; Christian, Jeff [Oak Ridge National Laboratory (ORNL)

    2012-04-01T23:59:59.000Z

    The foundation of a house is a sometimes ignored component of the building because of its low visibility. It is increasingly evident, however, that attention to good foundation design and construction significantly benefits the homeowner and the builder by mitigating future problems. Good foundation design and construction practice involves not only insulating to save energy but also providing effective structural design as well as moisture, termite, and radon control techniques as appropriate. Energy efficiency in housing is augmented by use of exterior slab and basement insulation, but high moisture content in the insulation material has led to concerns about its durability. The activity under this task was to extract six different exterior insulation systems that were characterized at installation and have been in the ground for 9 months to 15 years. R-value and moisture content were measured and inspections conducted for evidence of termite intrusion or deterioration. Based on the results, the durability of the various systems has been documented and assessments made of which systems appear to be best practice. Heat flux and temperature measurement data had been archived for some of the exterior insulation tests, thereby providing a unique opportunity to assess energy-saving performance and durability over the long term. The results show that the durability of foundation insulation systems depends on insulation type as well as on foundation type and local boundary conditions, the latter of which may have a marked influence on the durability of energy-saving performance.

  9. Materials - Next-generation insulation ... | ornl.gov

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

    Materials - Next-generation insulation ... A composite foam insulation panel being developed by Oak Ridge National Laboratory and partners could reduce wall-generated heating and...

  10. Exterior Rigid Insulation Best Practices - Building America Top...

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

    Effec guid-exterior rigid insulation.jpg For years, Building America research teams have advocated using the thermal, air, and vapor properties of rigid foam sheathing insulation...

  11. Building America Expert Meeting Report: Interior Insulation Retrofit...

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

    Interior Insulation Retrofit of Mass Masonry Wall Assembliesessment of risk factors for premature building deterioration due to interior insulation retrofits, and methods to reduce...

  12. Sensitivity of forced air distribution system efficiency to climate, duct location, air leakage and insulation

    E-Print Network [OSTI]

    Walker, Iain

    2001-01-01T23:59:59.000Z

    Location, Air Leakage and Insulation Iain S. Walker Energy4 Duct Insulation, Location and Leakageinsulation

  13. Fabrication of heterojunction solar cells by improved tin oxide deposition on insulating layer

    DOE Patents [OSTI]

    Feng, Tom (Morris Plains, NJ); Ghosh, Amal K. (New Providence, NJ)

    1980-01-01T23:59:59.000Z

    Highly efficient tin oxide-silicon heterojunction solar cells are prepared by heating a silicon substrate, having an insulating layer thereon, to provide a substrate temperature in the range of about 300.degree. C. to about 400.degree. C. and thereafter spraying the so-heated substrate with a solution of tin tetrachloride in a organic ester boiling below about 250.degree. C. Preferably the insulating layer is naturally grown silicon oxide layer.

  14. Thermal Performance of Exterior Insulation and Finish Systems Containing Vacuum Insulation Panels

    SciTech Connect (OSTI)

    Childs, Kenneth W [ORNL; Stovall, Therese K [ORNL; Biswas, Kaushik [ORNL; Carbary, Lawrence D [Dow Corning Corporation, Midland, MI

    2013-01-01T23:59:59.000Z

    A high-performance wall system is under development to improve wall thermal performance to a level of U-factor of 0.19 W/(m2 K) (R-30 [h ft2 F]/Btu) in a standard wall thickness by incorporating vacuum insulation panels (VIPs) into an exterior insulation finish system (EIFS). Such a system would be applicable to new construction and will offer a solution to more challenging retrofit situations as well. Multiple design options were considered to balance the need to protect theVIPs during construction and building operation, while minimizing heat transfer through the wall system. The results reported here encompass an indepth assessment of potential system performances including thermal modeling, detailed laboratory measurements under controlled conditions on the component, and system levels according to ASTM C518 (ASTM 2010). The results demonstrate the importance of maximizing the VIP coverage over the wall face. The results also reveal the impact of both the design and execution of system details, such as the joints between adjacent VIPs. The test results include an explicit modeled evaluation of the system performance in a clear wall.

  15. Removable fibrous glass insulation fitted to complex equipment shapes results in $178,000/yr savings

    SciTech Connect (OSTI)

    Not Available

    1985-08-01T23:59:59.000Z

    In early 1980, PPG Industries embarked on a general plant energy conservation effort at its Lake Charles, LA plant where chlor-alkalis, various chlorinated hydrocarbons, and vinyl chloride monomer are manufactured. Company engineers sought a means of insulating process steam components that, because of their complex shapes, were not (and normally are not) insulated. These components included flanges on heat exchanger heads and reboilers, steam valves in process areas, manways and other equipment. PPG plant engineers specified removable, reusable blanket insulation. The blankets are constructed of a fibrous glass mat form insulation encased in a silicone-impregnated glass cloth or similar weather barrier. Each insulation blanket was custom-made for its particular equipment shape and service application to ensure a close fit and optimal energy efficiency. Insulation thickness, type of weather barrier, and mesh were specified according to intended use. For protection from abrasion or puncture, some of the blankets also were covered with stainless steel, Monel, or Inconel wire mesh. Overall, the blankets provide high strength, durability, low thermal conductivity ratings, and an operating range of up to 1200/sup 0/F. Reduced maintenance costs and improved worker productivity have been evidenced since installing the blanket insulation. Further, PPG has increased energy efficiency. Project savings were tracked for 30 months (insulation and installation costs vs. fuel and maintenance savings) and revealed annual plant savings of $178,000-$130,000 in energy savings and $48,000 in maintenance savings. With the cost of the insulation blankets being about $125,000, PPG recovered its investment in under a year.

  16. Automatic insulation resistance testing apparatus

    DOE Patents [OSTI]

    Wyant, Francis J.; Nowlen, Steven P.; Luker, Spencer M.

    2005-06-14T23:59:59.000Z

    An apparatus and method for automatic measurement of insulation resistances of a multi-conductor cable. In one embodiment of the invention, the apparatus comprises a power supply source, an input measuring means, an output measuring means, a plurality of input relay controlled contacts, a plurality of output relay controlled contacts, a relay controller and a computer. In another embodiment of the invention the apparatus comprises a power supply source, an input measuring means, an output measuring means, an input switching unit, an output switching unit and a control unit/data logger. Embodiments of the apparatus of the invention may also incorporate cable fire testing means. The apparatus and methods of the present invention use either voltage or current for input and output measured variables.

  17. Slab edge insulating form system and methods

    DOE Patents [OSTI]

    Lee, Brain E. (Corral de Tierra, CA); Barsun, Stephan K. (Davis, CA); Bourne, Richard C. (Davis, CA); Hoeschele, Marc A. (Davis, CA); Springer, David A. (Winters, CA)

    2009-10-06T23:59:59.000Z

    A method of forming an insulated concrete foundation is provided comprising constructing a foundation frame, the frame comprising an insulating form having an opening, inserting a pocket former into the opening; placing concrete inside the foundation frame; and removing the pocket former after the placed concrete has set, wherein the concrete forms a pocket in the placed concrete that is accessible through the opening. The method may further comprise sealing the opening by placing a sealing plug or sealing material in the opening. A system for forming an insulated concrete foundation is provided comprising a plurality of interconnected insulating forms, the insulating forms having a rigid outer member protecting and encasing an insulating material, and at least one gripping lip extending outwardly from the outer member to provide a pest barrier. At least one insulating form has an opening into which a removable pocket former is inserted. The system may also provide a tension anchor positioned in the pocket former and a tendon connected to the tension anchor.

  18. Excavationless Exterior Foundation Insulation Field Study

    SciTech Connect (OSTI)

    Schirber, T.; Mosiman, G.; Ojczyk, C.

    2014-10-01T23:59:59.000Z

    Building science research supports installing exterior (soil side) foundation insulation as the optimal method to enhance the hygrothermal performance of new homes. With exterior foundation insulation, water management strategies are maximized while insulating the basement space and ensuring a more even temperature at the foundation wall. However, such an approach can be very costly and disruptive when applied to an existing home, requiring deep excavation around the entire house. The NorthernSTAR Building America Partnership team implemented an innovative, minimally invasive foundation insulation upgrade technique on an existing home. The approach consisted of using hydrovac excavation technology combined with a liquid insulating foam. The team was able to excavate a continuous 4" wide by 4' to 5' deep trench around the entire house, 128 linear feet, except for one small part under the stoop that was obstructed with concrete debris. The combination pressure washer and vacuum extraction technology also enabled the elimination of large trenches and soil stockpiles normally produced by backhoe excavation. The resulting trench was filled with liquid insulating foam, which also served as a water-control layer of the assembly. The insulation was brought above grade using a liquid foam/rigid foam hybrid system and terminated at the top of the rim joist. Cost savings over the traditional excavation process ranged from 23% to 50%. The excavationless process could result in even greater savings since replacement of building structures, exterior features, utility meters, and landscaping would be minimal or non-existent in an excavationless process.

  19. Insulation failure assessment under random energization overvoltages

    SciTech Connect (OSTI)

    Mahdy, A.M.; Anis, H.I. [Cairo Univ. (Egypt)] [Cairo Univ. (Egypt); El-Morshedy, A. [Faculty of Science for Girls, Dammam (Saudi Arabia)] [Faculty of Science for Girls, Dammam (Saudi Arabia)

    1996-03-01T23:59:59.000Z

    This paper offers a new simple approach to the evaluation of the risk of failure of external insulation in view of their known probabilistic nature. This is applied to EHV transmission systems subjected to energization overvoltages. The randomness, both in the applied stresses and insulation`s withstand characteristics are numerically simulated and then integrated to assess the risk of failure. Overvoltage control methods are accounted for, such as the use of pre-insertion breaker resistors, series capacitive compensation, and the installation of shunt reactors.

  20. Measure Guideline: Hybrid Foundation Insulation Retrofits

    SciTech Connect (OSTI)

    Ueno, K.; Lstiburek, J.

    2012-05-01T23:59:59.000Z

    This measure guideline provides recommendations for designs and variations for retrofit hybrid assemblies in improving interior foundation insulation and water management of basements. Variations include closed cell spray foam (ccSPF) with membrane waterproofing or air gap membrane drainage layers, rigid board foam insulation at flat walls (cast concrete or CMU block), a 'partial drainage' detail making use of the bulk water drainage that occurs through the field of a rubble stone wall, and non-drained spray foam assemblies (including slab insulation).

  1. Silicon on insulator achieved using electrochemical etching

    DOE Patents [OSTI]

    McCarthy, Anthony M. (Menlo Park, CA)

    1997-01-01T23:59:59.000Z

    Bulk crystalline silicon wafers are transferred after the completion of circuit fabrication to form thin films of crystalline circuitry on almost any support, such as metal, semiconductor, plastic, polymer, glass, wood, and paper. In particular, this technique is suitable to form silicon-on-insulator (SOI) wafers, whereby the devices and circuits formed exhibit superior performance after transfer due to the removal of the silicon substrate. The added cost of the transfer process to conventional silicon fabrication is insignificant. No epitaxial, lift-off, release or buried oxide layers are needed to perform the transfer of single or multiple wafers onto support members. The transfer process may be performed at temperatures of 50.degree. C. or less, permits transparency around the circuits and does not require post-transfer patterning. Consequently, the technique opens up new avenues for the use of integrated circuit devices in high-brightness, high-resolution video-speed color displays, reduced-thickness increased-flexibility intelligent cards, flexible electronics on ultrathin support members, adhesive electronics, touch screen electronics, items requiring low weight materials, smart cards, intelligent keys for encryption systems, toys, large area circuits, flexible supports, and other applications. The added process flexibility also permits a cheap technique for increasing circuit speed of market driven technologies such as microprocessors at little added expense.

  2. Silicon on insulator achieved using electrochemical etching

    DOE Patents [OSTI]

    McCarthy, A.M.

    1997-10-07T23:59:59.000Z

    Bulk crystalline silicon wafers are transferred after the completion of circuit fabrication to form thin films of crystalline circuitry on almost any support, such as metal, semiconductor, plastic, polymer, glass, wood, and paper. In particular, this technique is suitable to form silicon-on-insulator (SOI) wafers, whereby the devices and circuits formed exhibit superior performance after transfer due to the removal of the silicon substrate. The added cost of the transfer process to conventional silicon fabrication is insignificant. No epitaxial, lift-off, release or buried oxide layers are needed to perform the transfer of single or multiple wafers onto support members. The transfer process may be performed at temperatures of 50 C or less, permits transparency around the circuits and does not require post-transfer patterning. Consequently, the technique opens up new avenues for the use of integrated circuit devices in high-brightness, high-resolution video-speed color displays, reduced-thickness increased-flexibility intelligent cards, flexible electronics on ultrathin support members, adhesive electronics, touch screen electronics, items requiring low weight materials, smart cards, intelligent keys for encryption systems, toys, large area circuits, flexible supports, and other applications. The added process flexibility also permits a cheap technique for increasing circuit speed of market driven technologies such as microprocessors at little added expense. 57 figs.

  3. 1 Introduction 3 2 Topological insulators -Overview 5

    E-Print Network [OSTI]

    Johannesson, Henrik

    Contents 1 Introduction 3 2 Topological insulators - Overview 5 2.1 Introduction quantum spin Hall insulator . . . . . . . . . . . . . 7 2.4 Three dimensional topological insulator . . . . . . . . . . . . . . . . 9 3 Bulk band structure in a 2D spin orbit induced topological insulator 11 3.1 Introduction

  4. Advanced insulations for refrigerator/freezers: The potential for new shell designs incorporating polymer barrier construction

    SciTech Connect (OSTI)

    Griffith, B.T.; Arasteh, D.

    1992-11-01T23:59:59.000Z

    The impending phase-out of chlorofluorocarbons (CFCs) used to expand foam insulation, combined with requirements for increased energy efficiency, make the use of non-CFC-based high performance insulation technologies increasingly attractive. The majority of current efforts are directed at using advanced insulations in the form of thin, flat low-conductivity gas-filled or evacuated orthogonal panels, which we refer to as Advanced Insulation Panels (AIPs). AIPs can be used in composite with blown polymer foams to improve insulation performance in refrigerator/freezers (R/Fs) of conventional design and manufacture. This AIP/foam composite approach is appealing because it appears to be a feasible, near-term method for incorporating advanced insulations into R/Fs without substantial redesign or retooling. However, the requirements for adequate flow of foam during the foam-in-place operation impose limitations on the allowable thickness and coverage area of AIPs. This report examines design alternatives which may offer a greater increase in overall thermal resistance than is possible with the use of AIP/foam composites in current R/F design. These design alternatives generally involve a basic redesign of the R/F taking into account the unique requirements of advanced insulations and the importance of minimizing thermal bridging with high thermal resistance insulations. The focus here is on R/F doors because they are relatively simple and independent R/F components and are therefore good candidates for development of alterative designs. R/F doors have significant thermal bridging problems due to the steel outer shell construction. A three dimensional finite difference computer modeling exercise of a R/F door geometry was used to compare the overall levels of thermal resistance (R-value) for various design configurations.

  5. Air leakage of Insulated Concrete Form houses

    E-Print Network [OSTI]

    Durschlag, Hannah (Hanna Rebekah)

    2012-01-01T23:59:59.000Z

    Air leakage has been shown to increase building energy use due to additional heating and cooling loads. Although many construction types have been examined for leakage, an exploration of a large number of Insulated Concrete ...

  6. Insulate Steam Distribution and Condensate Return Lines

    SciTech Connect (OSTI)

    Not Available

    2006-01-01T23:59:59.000Z

    This revised ITP tip sheet on insulating steam distribution and condensate return lines provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  7. Saving Energy and Money with Aerogel Insulation

    Broader source: Energy.gov [DOE]

    The Energy Department is investing in an innovative insulation material that saves energy and money for industrial facilities while also helping to support 50 full-time clean energy jobs for Americans.

  8. Install Removable Insulation on Valves and Fittings

    SciTech Connect (OSTI)

    Not Available

    2006-01-01T23:59:59.000Z

    This revised ITP tip sheet on installing removable insulation on valves and fittings provides how-to advice for improving the system using low-cost, proven practices and technologies.

  9. Nonlinear boundary value problem of magnetic insulation

    E-Print Network [OSTI]

    A. V. Sinitsyn

    2000-09-09T23:59:59.000Z

    On the basis of generalization of upper and lower solution method to the singular two point boundary value problems, the existence theorem of solutions for the system, which models a process of magnetic insulation in plasma is proved.

  10. Metal-insulator transition in holography

    E-Print Network [OSTI]

    Aristomenis Donos; Sean A. Hartnoll

    2013-01-19T23:59:59.000Z

    We exhibit an interaction-driven metal-insulator quantum phase transition in a holographic model. Use of a helical lattice enables us to break translation invariance while preserving homogeneity. The metallic phase is characterized by a sharp Drude peak and a d.c. resistivity that increases with temperature. In the insulating phase the Drude spectral weight is transferred into a `mid-infrared' peak and to energy scales of order the chemical potential. The d.c. resistivity now decreases with temperature. In the metallic phase, operators breaking translation invariance are irrelevant at low energy scales. In the insulating phase, translation symmetry breaking effects are present at low energies. We find the near horizon extremal geometry that captures the insulating physics.

  11. Phosphorylation based insulation devices design and implementation

    E-Print Network [OSTI]

    Rivera Ortiz, Phillip M. (Phillip Michael)

    2013-01-01T23:59:59.000Z

    This thesis presents the analysis of a phosphorylation based insulation device implemented in Saccharomyces cerevisae and the minimization of the retroactivity to the input and retroactivity to the output of a single cycle ...

  12. Thermal conductivity of thermal-battery insulations

    SciTech Connect (OSTI)

    Guidotti, R.A.; Moss, M.

    1995-08-01T23:59:59.000Z

    The thermal conductivities of a variety of insulating materials used in thermal batteries were measured in atmospheres of argon and helium using several techniques. (Helium was used to simulate the hydrogen atmosphere that results when a Li(Si)/FeS{sub 2} thermal battery ages.) The guarded-hot-plate method was used with the Min-K insulation because of its extremely low thermal conductivity. For comparison purposes, the thermal conductivity of the Min-K insulating board was also measured using the hot-probe method. The thermal-comparator method was used for the rigid Fiberfrax board and Fiberfrax paper. The thermal conductivity of the paper was measured under several levels of compression to simulate the conditions of the insulating wrap used on the stack in a thermal battery. The results of preliminary thermal-characterization tests with several silica aerogel materials are also presented.

  13. PHYSICAL REVIEW B 83, 165440 (2011) Electron interaction-driven insulating ground state in Bi2Se3 topological insulators

    E-Print Network [OSTI]

    Wang, Wei Hua

    2011-01-01T23:59:59.000Z

    topological insulators in the two-dimensional limit Minhao Liu,1 Cui-Zu Chang,1,2 Zuocheng Zhang,1 Yi Zhang,2 of ultrathin Bi2Se3 topological insulators with thickness from one quintuple layer to six quintuple layers that this unusual insulating ground state in the two-dimensional limit of topological insulators is induced

  14. T-Duality and Topological Insulators

    E-Print Network [OSTI]

    Mathai, Varghese

    2015-01-01T23:59:59.000Z

    It is well known that topological insulators are classified by a family of groups, which coincidentally also classifies D-brane charges on orientifolds in string theory. In this letter, we extend this correlation via a geometric analog of the real Fourier transform to obtain a novel duality of topological insulators that can be viewed as a condensed matter analog of T-duality in string theory.

  15. Status of surface conduction in topological insulators

    SciTech Connect (OSTI)

    Barua, Sourabh, E-mail: sbarua@iitk.ac.in; Rajeev, K. P. [Department of Physics, Indian Institute of Technology Kanpur, Kanpur 208016 (India)] [Department of Physics, Indian Institute of Technology Kanpur, Kanpur 208016 (India)

    2014-01-15T23:59:59.000Z

    In this report, we scrutinize the thickness dependent resistivity data from the recent literature on electrical transport measurements in topological insulators. A linear increase in resistivity with increase in thickness is expected in the case of these materials since they have an insulating bulk and a conducting surface. However, such a trend is not seen in the resistivity versus thickness data for all the cases examined, except for some samples, where it holds for a range of thickness.

  16. Panelized wall system with foam core insulation

    DOE Patents [OSTI]

    Kosny, Jan (Oak Ridge, TN); Gaskin, Sally (Houston, TX)

    2009-10-20T23:59:59.000Z

    A wall system includes a plurality of wall members, the wall members having a first metal panel, a second metal panel, and an insulating core between the first panel and the second panel. At least one of the first panel and the second panel include ridge portions. The insulating core can be a foam, such as a polyurethane foam. The foam can include at least one opacifier to improve the k-factor of the foam.

  17. A Guide to Insulation Selection for Industrial Applications

    E-Print Network [OSTI]

    Harrison, M. R.

    1979-01-01T23:59:59.000Z

    of new insulations on th mar ket, it is important that the insulation selection process be upgraded. Insulation peci fications need to be reviewed in terms of new products and installation techniques. Also, the specific application or end use should... be critically analyzed to determine whic~ pro f ducts are best suited for that application. INSULATION MATERIAL SELECTION The selection and specification of insulation materials can be broken down int two I separate but interrelated activities. The first...

  18. Topological insulators and superconductors from string theory

    SciTech Connect (OSTI)

    Ryu, Shinsei; Takayanagi, Tadashi [Department of Physics, University of California, Berkeley, California 94720 (United States); Institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, Kashiwa, Chiba 277-8582 (Japan)

    2010-10-15T23:59:59.000Z

    Topological insulators and superconductors in different spatial dimensions and with different discrete symmetries have been fully classified recently, revealing a periodic structure for the pattern of possible types of topological insulators and superconductors, both in terms of spatial dimensions and in terms of symmetry classes. It was proposed that K theory is behind the periodicity. On the other hand, D-branes, a solitonic object in string theory, are also known to be classified by K theory. In this paper, by inspecting low-energy effective field theories realized by two parallel D-branes, we establish a one-to-one correspondence between the K-theory classification of topological insulators/superconductors and D-brane charges. In addition, the string theory realization of topological insulators and superconductors comes naturally with gauge interactions, and the Wess-Zumino term of the D-branes gives rise to a gauge field theory of topological nature, such as ones with the Chern-Simons term or the {theta} term in various dimensions. This sheds light on topological insulators and superconductors beyond noninteracting systems, and the underlying topological field theory description thereof. In particular, our string theory realization includes the honeycomb lattice Kitaev model in two spatial dimensions, and its higher-dimensional extensions. Increasing the number of D-branes naturally leads to a realization of topological insulators and superconductors in terms of holography (AdS/CFT).

  19. Topological Insulators and Superconductors from String Theory

    E-Print Network [OSTI]

    Shinsei Ryu; Tadashi Takayanagi

    2010-08-01T23:59:59.000Z

    Topological insulators and superconductors in different spatial dimensions and with different discrete symmetries have been fully classified recently, revealing a periodic structure for the pattern of possible types of topological insulators and supercondutors, both in terms of spatial dimensions and in terms of symmetry classes. It was proposed that K-theory is behind the periodicity. On the other hand, D-branes, a solitonic object in string theory, are also known to be classified by K-theory. In this paper, by inspecting low-energy effective field theories realized by two parallel D-branes, we establish a one-to-one correspondence between the K-theory classification of topological insulators/superconductors and D-brane charges. In addition, the string theory realization of topological insulators and superconductors comes naturally with gauge interactions, and the Wess-Zumino term of the D-branes gives rise to a gauge field theory of topological nature, such as ones with the Chern-Simons term or the $\\theta$-term in various dimensions. This sheds light on topological insulators and superconductors beyond non-interacting systems, and the underlying topological field theory description thereof. In particular, our string theory realization includes the honeycomb lattice Kitaev model in two spatial dimensions, and its higher-dimensional extensions. Increasing the number of D-branes naturally leads to a realization of topological insulators and superconductors in terms of holography (AdS/CFT).

  20. Magnetic insulation at finite temperatures

    SciTech Connect (OSTI)

    Goedecke, G. H.; Davis, Brian T.; Chen, Chiping [Physics Department, New Mexico State University, Las Cruces, New Mexico 88003 and Raytheon Missile Systems, 1151 E. Hermans Road, Tucson, Arizona 85706 (United States); Intense Beam Theoretical Research Group, Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 and Raytheon Missile Systems, 1151 E. Hermans Road, Tucson, Arizona 85706 (United States)

    2006-08-15T23:59:59.000Z

    A finite-temperature non-neutral plasma (FTNNP) theory of magnetically insulated (MI) electron flows in crossed-field vacuum devices is developed and applied in planar geometry. It is shown that, in contrast to the single type of MI flow predicted by traditional cold-plasma treatments, the nonlinear FTNNP equations admit five types of steady flow, of which three types are MI flows, including flows in which the electric field and/or the tangential velocity at the cathode may be zero or nonzero. It is also shown that finite-temperature Vlasov-Poisson treatments yield solutions for electron number densities and electrostatic potentials that are a subset of the FTNNP solutions. The algorithms that are used to solve the FTNNP equations numerically are discussed, and the numerical results are presented for several examples of the three types of MI flow. Results include prediction of the existence, boundaries, number density profiles, and other properties of sheaths of electrons in the anode-cathode gap.

  1. BOA: Pipe-asbestos insulation removal robot system

    SciTech Connect (OSTI)

    Schempf, H.; Bares, J.; Mutschler, E. [and others

    1995-12-31T23:59:59.000Z

    This paper describes the BOA system, a mobile pipe-external crawler used to remotely strip and bag (possibly contaminated) asbestos-containing lagging and insulation materials (ACLIM) from various diameter pipes in (primarily) industrial installations across the DOE weapons complex. The mechanical removal of ACLIM is very cost-effective due to the relatively low productivity and high cost involved in human removal scenarios. BOA, a mechanical system capable of removing most forms of lagging (paper, plaster, aluminum sheet, clamps, screws and chicken-wire), and insulation (paper, tar, asbestos fiber, mag-block) uses a circular cutter and compression paddles to cut and strip the insulation off the pipe through compression, while a HEPA-filter and encapsulant system maintain a certifiable vacuum and moisture content inside the system and on the pipe, respectively. The crawler system has been built and is currently undergoing testing. Key design parameters and performance parameters are developed and used in performance testing. Since the current system is a testbed, we also discuss future enhancements and outline two deployment scenarios (robotic and manual) for the final system to be designed and completed by the end of FY `95. An on-site demonstration is currently planned for Fernald in Ohio and Oak Ridge in Tennessee.

  2. Method for forming fibrous silicon carbide insulating material

    DOE Patents [OSTI]

    Wei, G.C.

    1983-10-12T23:59:59.000Z

    A method whereby silicon carbide-bonded SiC fiber composites are prepared from carbon-bonded C fiber composites is disclosed. Carbon-bonded C fiber composite material is treated with gaseous silicon monoxide generated from the reaction of a mixture of colloidal silica and carbon black at an elevated temperature in an argon atmosphere. The carbon in the carbon bond and fiber is thus chemically converted to SiC resulting in a silicon carbide-bonded SiC fiber composite that can be used for fabricating dense, high-strength high-toughness SiC composites or as thermal insulating materials in oxidizing environments.

  3. Method for forming fibrous silicon carbide insulating material

    DOE Patents [OSTI]

    Wei, George C. (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

    A method whereby silicon carbide-bonded SiC fiber composites are prepared from carbon-bonded C fiber composites is disclosed. Carbon-bonded C fiber composite material is treated with gaseous silicon monoxide generated from the reaction of a mixture of colloidal silica and carbon black at an elevated temperature in an argon atmosphere. The carbon in the carbon bond and fiber is thus chemically converted to SiC resulting in a silicon carbide-bonded SiC fiber composite that can be used for fabricating dense, high-strength high-toughness SiC composites or as thermal insulating materials in oxidizing environments.

  4. Insulating Structural Ceramics Program, Final Report

    SciTech Connect (OSTI)

    Andrews, Mark J.; Tandon, Raj; Ott, Eric; Hind, Abi Akar; Long, Mike; Jensen, Robert; Wheat, Leonard; Cusac, Dave; Lin, H. T.; Wereszczak, Andrew A.; Ferber, Mattison K.; Lee, Sun Kun; Yoon, Hyung K.; Moreti, James; Park, Paul; Rockwood, Jill; Boyer, Carrie; Ragle, Christie; Balmer-Millar, Marilou; Aardahl, Chris; Habeger, Craig; Rappe, Ken; Tran, Diana; Koshkarian, Kent; Readey, Michael; ,

    2005-11-22T23:59:59.000Z

    New materials and corresponding manufacturing processes are likely candidates for diesel engine components as society and customers demand lower emission engines without sacrificing power and fuel efficiency. Strategies for improving thermal efficiency directly compete with methodologies for reducing emissions, and so the technical challenge becomes an optimization of controlling parameters to achieve both goals. Approaches being considered to increase overall thermal efficiency are to insulate certain diesel engine components in the combustion chamber, thereby increasing the brake mean effective pressure ratings (BMEP). Achieving higher BMEP rating by insulating the combustion chamber, in turn, requires advances in material technologies for engine components such as pistons, port liners, valves, and cylinder heads. A series of characterization tests were performed to establish the material properties of ceramic powder. Mechanical chacterizations were also obtained from the selected materials as a function of temperature utilizing ASTM standards: fast fracture strength, fatique resistance, corrosion resistance, thermal shock, and fracture toughness. All ceramic materials examined showed excellent wear properties and resistance to the corrosive diesel engine environments. The study concluded that the ceramics examined did not meet all of the cylinder head insert structural design requirements. Therefore we do not recommend at this time their use for this application. The potential for increased stresses and temperatures in the hot section of the diesel engine combined with the highly corrosive combustion products and residues has driven the need for expanded materials capability for hot section engine components. Corrosion and strength requirements necessitate the examination of more advanced high temperture alloys. Alloy developments and the understanding of processing, structure, and properties of supperalloy materials have been driven, in large part, by the gas turbine community over the last fifty years. Characterization of these high temperature materials has, consequently, concentrated heavily upon application conditions similiar to to that encountered in the turbine engine environment. Significantly less work has been performed on hot corrosion degradation of these materials in a diesel engine environment. This report examines both the current high temperature alloy capability and examines the capability of advanced nickle-based alloys and methods to improve production costs. Microstructures, mechanical properties, and the oxidation/corrosion behavior of commercially available silicon nitride ceramics were investigated for diesel engine valve train applications. Contact, sliding, and scratch damage mechanisms of commercially available silicon nitride ceramics were investigated as a function of microstructure. The silicon nitrides with a course microstructure showed a higher material removal rate that agrees with a higher wear volume in the sliding contact tests. The overall objective of this program is to develop catalyst materials systems for an advanced Lean-NOx aftertreatment system that will provide high NOx reduction with minimum engine fuel efficiency penalty. With Government regulations on diesel engine NOx emissions increasingly becoming more restrictive, engine manufacturers are finding it difficult to meet the regulations solely with engine design strategies (i.e. improved combustion, retarded timing, exhaust gas recirculation, etc.). Aftertreatment is the logical technical approach that will be necessary to achieve the required emission levels while at the same time minimally impacting the engine design and its associated reliability and durability concerns.

  5. An Insulating Glass Knowledge Base

    SciTech Connect (OSTI)

    Michael L. Doll; Gerald Hendrickson; Gerard Lagos; Russell Pylkki; Chris Christensen; Charlie Cureija

    2005-08-01T23:59:59.000Z

    This report will discuss issues relevant to Insulating Glass (IG) durability performance by presenting the observations and developed conclusions in a logical sequential format. This concluding effort discusses Phase II activities and focuses on beginning to quantifying IG durability issues while continuing the approach presented in the Phase I activities (Appendix 1) which discuss a qualitative assessment of durability issues. Phase II developed a focus around two specific IG design classes previously presented in Phase I of this project. The typical box spacer and thermoplastic spacer design including their Failure Modes and Effect Analysis (FMEA) and Fault Tree diagrams were chosen to address two currently used IG design options with varying components and failure modes. The system failures occur due to failures of components or their interfaces. Efforts to begin quantifying the durability issues focused on the development and delivery of an included computer based IG durability simulation program. The focus/effort to deliver the foundation for a comprehensive IG durability simulation tool is necessary to address advancements needed to meet current and future building envelope energy performance goals. This need is based upon the current lack of IG field failure data and the lengthy field observation time necessary for this data collection. Ultimately, the simulation program is intended to be used by designers throughout the current and future industry supply chain. Its use is intended to advance IG durability as expectations grow around energy conservation and with the growth of embedded technologies as required to meet energy needs. In addition the tool has the immediate benefit of providing insight for research and improvement prioritization. Included in the simulation model presentation are elements and/or methods to address IG materials, design, process, quality, induced stress (environmental and other factors), validation, etc. In addition, acquired data is presented in support of project and model assumptions. Finally, current and suggested testing protocol and procedure for future model validation and IG physical testing are discussed.

  6. Dynamic predictive clothing insulation models based on outdoor air and indoor operative temperatures

    E-Print Network [OSTI]

    Schiavon, Stefano; Lee, Kwang Ho

    2012-01-01T23:59:59.000Z

    predictive clothing insulation models based on outdoor airrange of the clothing insulation calculated for eachbuilding). Figure 8 Clothing insulation versus dress code [

  7. Influence of two dynamic predictive clothing insulation models on building energy performance

    E-Print Network [OSTI]

    Lee, Kwang Ho; Schiavon, Stefano

    2013-01-01T23:59:59.000Z

    Predictive Clothing Insulation Models on Building Energyunnecessarily higher clothing insulation and lower heatingthat the constant clothing insulation assumption lead to the

  8. Predictive clothing insulation model based on outdoor air and indoor operative temperatures

    E-Print Network [OSTI]

    Schiavon, Stefano; Lee, Kwang Ho

    2012-01-01T23:59:59.000Z

    2012) Predictive clothing insulation model based on outdoorPredictive clothing insulation model based on outdoor airpredictive models of clothing insulation have been developed

  9. Versatile Indian sari: Clothing insulation with different drapes of typical sari ensembles

    E-Print Network [OSTI]

    Indraganti, Madhavi; Lee, Juyoun; Zhang, Hui; Arens, Edward

    2014-01-01T23:59:59.000Z

    Extension of the Clothing Insulation Database for Standardand air movement on that insulation. , s.l. : s.n. Havenith,Estimation of the thermal insulation and evaporative

  10. Topological insulators and topological nonlinear {sigma} models

    SciTech Connect (OSTI)

    Yao Hong; Lee, Dung-Hai [Department of Physics, University of California at Berkeley, Berkeley, California 94720 (United States) and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2010-12-15T23:59:59.000Z

    In this paper we link the physics of topological nonlinear {sigma} models with that of Chern-Simons insulators. We show that corresponding to every 2n-dimensional Chern-Simons insulator there is a (n-1)-dimensional topological nonlinear {sigma} model with the Wess-Zumino-Witten term. Breaking internal symmetry in these nonlinear {sigma} models leads to nonlinear {sigma} models with the {theta} term. [This is analogous to the dimension reduction leading from 2n-dimensional Chern-Simons insulators to (2n-1) and (2n-2)-dimensional topological insulators protected by discrete symmetries.] The correspondence described in this paper allows one to derive the topological term in a theory involving fermions and order parameters (we shall referred to them as ''fermion-{sigma} models'') when the conventional gradient-expansion method fails. We also discuss the quantum number of solitons in topological nonlinear {sigma} model and the electromagnetic action of the (2n-1)-dimensional topological insulators. Throughout the paper we use a simple model to illustrate how things work.

  11. Radio-transparent multi-layer insulation for radiowave receivers

    SciTech Connect (OSTI)

    Choi, J. [Korea University, Anam-dong Seongbuk-gu, Seoul 136-713 (Korea, Republic of)] [Korea University, Anam-dong Seongbuk-gu, Seoul 136-713 (Korea, Republic of); Ishitsuka, H. [Department of Particle and Nuclear Physics, School of High Energy Accelerator Science, The Graduate University for Advanced Studies (SOKENDAI), Shonan Village, Hayama, Kanagawa 240-0193 (Japan)] [Department of Particle and Nuclear Physics, School of High Energy Accelerator Science, The Graduate University for Advanced Studies (SOKENDAI), Shonan Village, Hayama, Kanagawa 240-0193 (Japan); Mima, S. [Terahertz Sensing and Imaging Team, Terahertz-wave Research Group, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)] [Terahertz Sensing and Imaging Team, Terahertz-wave Research Group, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Oguri, S., E-mail: shugo@post.kek.jp [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Oho, Tsukuba, Ibaraki 305-0801 (Japan); Takahashi, K. [Terahertz Sensing and Imaging Team, Terahertz-wave Research Group, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan) [Terahertz Sensing and Imaging Team, Terahertz-wave Research Group, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Department of Physics, Tohoku University, Sendai, Miyagi 980-8578 (Japan); Tajima, O. [Department of Particle and Nuclear Physics, School of High Energy Accelerator Science, The Graduate University for Advanced Studies (SOKENDAI), Shonan Village, Hayama, Kanagawa 240-0193 (Japan) [Department of Particle and Nuclear Physics, School of High Energy Accelerator Science, The Graduate University for Advanced Studies (SOKENDAI), Shonan Village, Hayama, Kanagawa 240-0193 (Japan); Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Oho, Tsukuba, Ibaraki 305-0801 (Japan)

    2013-11-15T23:59:59.000Z

    In the field of radiowave detection, enlarging the receiver aperture to enhance the amount of light detected is essential for greater scientific achievements. One challenge in using radio transmittable apertures is keeping the detectors cool. This is because transparency to thermal radiation above the radio frequency range increases the thermal load. In shielding from thermal radiation, a general strategy is to install thermal filters in the light path between aperture and detectors. However, there is difficulty in fabricating metal mesh filters of large diameters. It is also difficult to maintain large diameter absorptive-type filters in cold because of their limited thermal conductance. A technology that maintains cold conditions while allowing larger apertures has been long-awaited. We propose radio-transparent multi-layer insulation (RT-MLI) composed from a set of stacked insulating layers. The insulator is transparent to radio frequencies, but not transparent to infrared radiation. The basic idea for cooling is similar to conventional multi-layer insulation. It leads to a reduction in thermal radiation while maintaining a uniform surface temperature. The advantage of this technique over other filter types is that no thermal links are required. As insulator material, we used foamed polystyrene; its low index of refraction makes an anti-reflection coating unnecessary. We measured the basic performance of RT-MLI to confirm that thermal loads are lowered with more layers. We also confirmed that our RT-MLI has high transmittance to radiowaves, but blocks infrared radiation. For example, RT-MLI with 12 layers has a transmittance greater than 95% (lower than 1%) below 200 GHz (above 4 THz). We demonstrated its effects in a system with absorptive-type filters, where aperture diameters were 200 mm. Low temperatures were successfully maintained for the filters. We conclude that this technology significantly enhances the cooling of radiowave receivers, and is particularly suitable for large-aperture systems. This technology is expected to be applicable to various fields, including radio astronomy, geo-environmental assessment, and radar systems.

  12. Constraints on topological order in Mott Insulators

    E-Print Network [OSTI]

    Michael P. Zaletel; Ashvin Vishwanath

    2015-04-18T23:59:59.000Z

    We point out certain symmetry induced constraints on topological order in Mott Insulators (quantum magnets with an odd number of spin $\\tfrac{1}{2}$ per unit cell). We show, for example, that the double semion topological order is incompatible with time reversal and translation symmetry in Mott insulators. This sharpens the Hastings-Oshikawa-Lieb-Schultz-Mattis theorem for 2D quantum magnets, which guarantees that a fully symmetric gapped Mott insulator must be topologically ordered, but is silent on which topological order is permitted. An application of our result is the Kagome lattice quantum antiferromagnet where recent numerical calculations of entanglement entropy indicate a ground state compatible with either toric code or double semion topological order. Our result rules out the latter possibility.

  13. Multilayer insulation blanket, fabricating apparatus and method

    DOE Patents [OSTI]

    Gonczy, John D. (Oak Lawn, IL); Niemann, Ralph C. (Downers Grove, IL); Boroski, William N. (Aurora, IL)

    1992-01-01T23:59:59.000Z

    An improved multilayer insulation blanket for insulating cryogenic structures operating at very low temperatures is disclosed. An apparatus and method for fabricating the improved blanket are also disclosed. In the improved blanket, each successive layer of insulating material is greater in length and width than the preceding layer so as to accommodate thermal contraction of the layers closest to the cryogenic structure. The fabricating apparatus has a rotatable cylindrical mandrel having an outer surface of fixed radius that is substantially arcuate, preferably convex, in cross-section. The method of fabricating the improved blanket comprises (a) winding a continuous sheet of thermally reflective material around the circumference of the mandrel to form multiple layers, (b) binding the layers along two lines substantially parallel to the edges of the circumference of the mandrel, (c) cutting the layers along a line parallel to the axle of the mandrel, and (d) removing the bound layers from the mandrel.

  14. Method of fabricating a multilayer insulation blanket

    DOE Patents [OSTI]

    Gonczy, John D. (Oak Lawn, IL); Niemann, Ralph C. (Downers Grove, IL); Boroski, William N. (Aurora, IL)

    1993-01-01T23:59:59.000Z

    An improved multilayer insulation blanket for insulating cryogenic structures operating at very low temperatures is disclosed. An apparatus and method for fabricating the improved blanket are also disclosed. In the improved blanket, each successive layer of insulating material is greater in length and width than the preceding layer so as to accommodate thermal contraction of the layers closest to the cryogenic structure. The fabricating apparatus has a rotatable cylindrical mandrel having an outer surface of fixed radius that is substantially arcuate, preferably convex, in cross-section. The method of fabricating the improved blanket comprises (a) winding a continuous sheet of thermally reflective material around the circumference of the mandrel to form multiple layers, (b) binding the layers along two lines substantially parallel to the edges of the circumference of the mandrel, (c) cutting the layers along a line parallel to the axle of the mandrel, and (d) removing the bound layers from the mandrel.

  15. Nuclear reactor vessel fuel thermal insulating barrier

    DOE Patents [OSTI]

    Keegan, C. Patrick; Scobel, James H.; Wright, Richard F.

    2013-03-19T23:59:59.000Z

    The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel that has a hemispherical lower section that increases in volume from the center line of the reactor to the outer extent of the diameter of the thermal insulating barrier and smoothly transitions up the side walls of the vessel. The space between the thermal insulating harrier and the reactor vessel forms a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive inlet valve for the cooling water includes a buoyant door that is normally maintained sealed under its own weight and floats open when the cavity is Hooded. Passively opening steam vents are also provided.

  16. Insulation spacer eliminates electric shorts between lines

    SciTech Connect (OSTI)

    Colaizzi, J.F.; Rockafellow, G.B.

    1983-03-01T23:59:59.000Z

    The design criteria incorporated into the pipeline insulating spacer were: spacer material selected must have a very large compressive and tensile strength in order to withstand the weight and stress resulting on the pipelines; provide the necessary abrasive resistance, dielectric strength, and will not decay underground; must not soften with heat when used around or near stream lines or will not cold flow under pressure; minimum length and circumference to reduce ''Shielding Effects'' from any cathodic protection system; and provide a material that incorporates a maximum strength at a minimum thickness. Explains that electric shorts are caused by 2 or more metallic structures in contact with each other. Notes that the insulating spacer's use has been expanded to provide electrical and physical insulation between carrier pipe and casing, supports for piping in compressing stations, and for pipelines that are suspended on bridges.

  17. Is graphene in vacuum an insulator?

    E-Print Network [OSTI]

    Joaquín E. Drut; Timo A. Lähde

    2009-01-15T23:59:59.000Z

    We present evidence, from Lattice Monte Carlo simulations of the phase diagram of graphene as a function of the Coulomb coupling between quasiparticles, that graphene in vacuum is likely to be an insulator. We find a semimetal-insulator transition at $\\alpha_g^\\text{crit} = 1.11 \\pm 0.06$, where $\\alpha_g^{} \\simeq 2.16$ in vacuum, and $\\alpha_g^{} \\simeq 0.79$ on a SiO$_2^{}$ substrate. Our analysis uses the logarithmic derivative of the order parameter, supplemented by an equation of state. The insulating phase disappears above a critical number of four-component fermion flavors $4 < N_f^{\\text{crit}} < 6$. Our data are consistent with a second-order transition.

  18. Casimir repulsion between Topological Insulators in the diluted regime

    E-Print Network [OSTI]

    Pablo Rodriguez-Lopez

    2011-07-15T23:59:59.000Z

    The Pairwise Summation Approximation (PSA) of Casimir energy is applied to a system of two dielectrics with magnetoelectric coupling. In particular, the case of Topological Insulators (TI) is studied in detail. Depending on the the optical response of the TI, we obtain a stable equilibrium distance, atraction for all distances, or repulsion for all distances at zero temperature. This equilibrium distance disappears in the high temperature limit. These results are independent on the geometry of the TI, but are only valid in the diluted approximation.

  19. Development of New Generation of Thermally-Enhanced Fiber Glass Insulation

    SciTech Connect (OSTI)

    Kosny, Jan [ORNL; Yarbrough, David W [ORNL; Childs, Phillip W [ORNL; Miller, William A [ORNL; Atchley, Jerald Allen [ORNL; Shrestha, Som S [ORNL

    2010-03-01T23:59:59.000Z

    This report presents experimental and numerical results from thermal performance studies. The purpose of this Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC and John s Manville was to design a basic concept of a new generation of thermally-enhanced fiber glass insulation. Different types of Phase Change Materials (PCMs) have been tested as dynamic components in buildings during the last 4 decades. Most historical studies have found that PCMs enhance building energy performance. Some PCM-enhanced building materials, like PCM-gypsum boards or PCM-impregnated concretes have already found their limited applications in different countries. Today, continued improvements in building envelope technologies suggest that throughout Southern and Central U.S. climates, residences may soon be routinely constructed with PCM in order to maximize insulation effectiveness and maintain low heating and cooling loads. The proposed thermally-enhanced fiber glass insulation will maximize this integration by utilizing a highly-efficient building envelope with high-R thermal insulation, active thermal mass and superior air-tightness. Improved thermal resistance will come from modifications in infrared internal characteristics of the fiber glass insulation. Thermal mass effect can be provided by proprietary thermally-active microencapsulated phase change material (PCM). Work carried out at the Oak Ridge National Laboratory (ORNL) on the CRADA is described in this report.

  20. Edge modes in band topological insulators

    E-Print Network [OSTI]

    Lukasz Fidkowski; T. S. Jackson; Israel Klich

    2011-05-09T23:59:59.000Z

    We characterize gapless edge modes in translation invariant topological insulators. We show that the edge mode spectrum is a continuous deformation of the spectrum of a certain gluing function defining the occupied state bundle over the Brillouin zone (BZ). Topologically non-trivial gluing functions, corresponding to non-trivial bundles, then yield edge modes exhibiting spectral flow. We illustrate our results for the case of chiral edge states in two dimensional Chern insulators, as well as helical edges in quantum spin Hall states.

  1. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, Anthony M. (Menlo Park, CA)

    1998-06-02T23:59:59.000Z

    A method for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors.

  2. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, A.M.

    1996-01-30T23:59:59.000Z

    A method is disclosed for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors. 10 figs.

  3. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, Anthony M. (Menlo Park, CA)

    1996-01-01T23:59:59.000Z

    A method for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors.

  4. Silicon on insulator with active buried regions

    DOE Patents [OSTI]

    McCarthy, A.M.

    1998-06-02T23:59:59.000Z

    A method is disclosed for forming patterned buried components, such as collectors, sources and drains, in silicon-on-insulator (SOI) devices. The method is carried out by epitaxially growing a suitable sequence of single or multiple etch stop layers ending with a thin silicon layer on a silicon substrate, masking the silicon such that the desired pattern is exposed, introducing dopant and activating in the thin silicon layer to form doped regions. Then, bonding the silicon layer to an insulator substrate, and removing the silicon substrate. The method additionally involves forming electrical contact regions in the thin silicon layer for the buried collectors. 10 figs.

  5. Observation of a Macroscopically Quantum-Entangled Insulator

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

    Insulator Print Wednesday, 27 May 2009 00:00 It has recently been proposed that insulators with large band gaps and strong spin-orbit coupling can host a new phase of...

  6. Observation of a Macroscopically Quantum-Entangled Insulator

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

    of a Macroscopically Quantum-Entangled Insulator Print It has recently been proposed that insulators with large band gaps and strong spin-orbit coupling can host a new phase of...

  7. Gapped symmetry preserving surface state for the electron topological insulator

    E-Print Network [OSTI]

    Wang, Chong

    It is well known that the three-dimensional (3D) electronic topological insulator (TI) with charge-conservation and time-reversal symmetry cannot have a trivial insulating surface that preserves symmetry. It is often ...

  8. A Rapid Scanning Inspection Method for Insulated Ferromagnetic Tubing

    E-Print Network [OSTI]

    Marsh, G. M.; Milewits, M.

    1984-01-01T23:59:59.000Z

    long expanse of insulated piping. PA Incorporated has developed an electromagnetic inspection device which rapidly scans nearly 100 percent of an insulated pipeline (flanges and tees excluded) and provides a quantitative (2 percent) measurement...

  9. An analytical and experimental investigation for an interstitial insulation technology

    E-Print Network [OSTI]

    Kim, Dong Keun

    2009-05-15T23:59:59.000Z

    ) as the interstitial insulation material. Both the inner and outer surface temperatures of the coaxial pipes were measured in order to evaluate the effective thermal conductivity and thermal diffusivity of the insulation concept. The predicted results from the model...

  10. Classification and characterization of topological insulators and superconductors

    E-Print Network [OSTI]

    Mong, Roger

    2012-01-01T23:59:59.000Z

    Weak topological insulators (WTI) . . . . . 1.4 Topologicalweak topological insulators (WTI). The surfaces of STIs haveSTI STM TI TRIM/TRIMs TRS TKNN VPT WTI one-dimension, two-

  11. antiferromagnetic mott insulator: Topics by E-print Network

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

    A&M University - TxSpace Summary: PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram...

  12. atomic mott insulator: Topics by E-print Network

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

    A&M University - TxSpace Summary: PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram...

  13. Moisture Durability of Vapor Permeable Insulating Sheathing (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-10-01T23:59:59.000Z

    In this project, Building America team Building Science Corporation researched some of the ramifications of using exterior, vapor permeable insulation on retrofit walls with vapor permeable cavity insulation. Retrofit strategies are a key factor in reducing exterior building stock consumption.

  14. Performance of Titanium-Oxide/Polymer Insulation in Bi-2212/Ag-alloy Round Wire Wound Superconducting Coils

    E-Print Network [OSTI]

    Peng Chen; Ulf P Trociewitz; Matthieu Dalban-Canassy; Jianyi Jiang; Eric E Hellstrom; David C Larbalestier

    2013-03-20T23:59:59.000Z

    Conductor insulation is one of the key components needed to make Ag-alloy clad Bi2Sr2CaCu2O8+x (Bi-2212/Ag) superconducting round wire (RW) successful for high field magnet applications as dielectric standoff and high winding current densities (Jw) directly depend on it. In this study, a TiO2/polymer insulation coating developed by nGimat LLC was applied to test samples and a high field test coil. The insulation was investigated by differential thermal analysis (DTA), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), dielectric properties measurement, and transport critical current (Ic) properties measurement. About 29% of the insulation by weight is polymer. When the Bi-2212/Ag wire is full heat treated, this decomposes with slow heating to 400{\\deg}C in pure O2. After the full reaction, we found that the TiO2 did not degrade the critical current properties, adhered well to the conductor, and provided a breakdown voltage of >100 V, which allowed the test coil to survive quenching in 31.2 T background field, while providing a 2.6 T field increment. For Bi-2212/Ag RW with a typical diameter of 1.0-1.5 mm, this ~15 um thick insulation allows a very high coil packing factor of ~0.74, whereas earlier alumino-silicate braid insulation only allows packing factors of 0.38-0.48.

  15. Evaluation of Magnetic Insulation in SF6 Filled Regions

    SciTech Connect (OSTI)

    Houck, T; Ferriera, T; Goerz, D; Javedani, J; Speer, R; Tully, L; Vogtlin, G

    2009-06-08T23:59:59.000Z

    The use of magnetic fields perpendicular to quasistatic electric fields to deter electrical breakdown in vacuum, referred to as magnetic insulation, is well understood and used in numerous applications. Here we define quasi-static as applied high-voltage pulse widths much longer than the transit time of light across the electrode gap. For this report we extend the concept of magnetic insulation to include the inhibition of electrical breakdown in gases. Ionization and electrical breakdown of gases in crossed electric and magnetic fields is only a moderately explored research area. For sufficiently large magnetic fields an electron does not gain sufficient energy over a single cycloidal path to ionize the gas molecules. However, it may be possible for the electron to gain sufficient energy for ionization over a number of collisions. To study breakdown in a gas, the collective behavior of an avalanche of electrons in the formation of a streamer in the gas is required. Effective reduced electric field (EREF) theory, which considers the bulk properties of an electron avalanche, has been successful at describing the influence of a crossed magnetic field on the electric field required for breakdown in gases; however, available data to verify the theory has been limited to low gas pressures and weak electronegative gases. High power devices, for example explosively driven magnetic flux compressors, operate at electrical field stresses, magnetic fields, and insulating gas pressures nearly two orders of magnitude greater than published research for crossed fields in gases. The primary limitation of conducting experiments at higher pressures, e.g. atmospheric, is generating the large magnetic fields, 10's Tesla, and electric fields, >100 kV/cm, required to see a significant effect. In this paper we describe measurements made with a coaxial geometry diode, form factor of 1.2, operating at peak electrical field stress of 220 kV/cm, maximum magnetic field of 20 Tesla, and SF{sub 6} pressure of 760 torr.

  16. Mechanics of Insulator Behavior in Concrete Crosstie Fastening Systems

    E-Print Network [OSTI]

    Barkan, Christopher P.L.

    of Insulator Behavior Analysis of failure modes and causes · Failure Mode and Effect Analysis (FMEA) used

  17. Topological insulators and superconductors Xiao-Liang Qi

    E-Print Network [OSTI]

    Wu, Zhigang

    Topological insulators and superconductors Xiao-Liang Qi Microsoft Research, Station Q, Elings Hall, California 94305, USA (Received 2 August 2010; published 14 October 2011) Topological insulators are new-dimensional and three-dimensional topological insulators are reviewed, and both the topological band theory

  18. Molecular Cell Mode of Regulation and the Insulation

    E-Print Network [OSTI]

    Molecular Cell Article Mode of Regulation and the Insulation of Bacterial Gene Expression Vered.molcel.2012.04.032 SUMMARY A gene can be said to be insulated from environ- mental variations if its the insulation of the lac promoter of E. coli and of synthetic constructs in which the transcription factor CRP

  19. MOTT INSULATORS, SPIN LIQUIDS AND QUANTUM DISORDERED SUPERCONDUCTIVITY

    E-Print Network [OSTI]

    COURSE 7 MOTT INSULATORS, SPIN LIQUIDS AND QUANTUM DISORDERED SUPERCONDUCTIVITY MATTHEW P.A. FISHER insulators and quantum magnetism 583 3.1 Spin models and quantum magnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . 637 #12;MOTT INSULATORS, SPIN LIQUIDS AND QUANTUM DISORDERED SUPERCONDUCTIVITY Matthew P.A. Fisher

  20. The Insulation Energy Appraisal Assessing the True Value of Insulated System

    E-Print Network [OSTI]

    Schell, S.

    Insulation remains a seriously under-utilized technology in the manufacturing and industrial sectors of the economy even though its role in energy efficiency and environmental preservation is clear. The objective of the presentation is to educate...

  1. D-Algebra Structure of Topological Insulators

    E-Print Network [OSTI]

    B. Estienne; N. Regnault; B. A. Bernevig

    2013-02-01T23:59:59.000Z

    In the quantum Hall effect, the density operators at different wave-vectors generally do not commute and give rise to the Girvin MacDonald Plazmann (GMP) algebra with important consequences such as ground-state center of mass degeneracy at fractional filling fraction, and W_{1 + \\infty} symmetry of the filled Landau levels. We show that the natural generalization of the GMP algebra to higher dimensional topological insulators involves the concept of a D-algebra formed by using the fully anti-symmetric tensor in D-dimensions. For insulators in even dimensional space, the D-algebra is isotropic and closes for the case of constant non-Abelian F(k) ^ F(k) ... ^ F(k) connection (D-Berry curvature), and its structure factors are proportional to the D/2-Chern number. In odd dimensions, the algebra is not isotropic, contains the weak topological insulator index (layers of the topological insulator in one less dimension) and does not contain the Chern-Simons \\theta form (F ^ A - 2/3 A ^ A ^ A in 3 dimensions). The Chern-Simons form appears in a certain combination of the parallel transport and simple translation operator which is not an algebra. The possible relation to D-dimensional volume preserving diffeomorphisms and parallel transport of extended objects is also discussed.

  2. Cladding Attachment Over Thick Exterior Insulating Sheathing

    SciTech Connect (OSTI)

    Baker, P.; Eng, P.; Lepage, R.

    2014-01-01T23:59:59.000Z

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of both wood framed walls as well as mass masonry wall assemblies. For thick layers of exterior insulation (levels greater than 1.5 inches), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location (Straube and Smegal 2009, Pettit 2009, Joyce 2009, Ueno 2010). The research presented in this report is intended to help develop a better understanding of the system mechanics involved and the potential for environmental exposure induced movement between the furring strip and the framing. BSC sought to address the following research questions: 1. What are the relative roles of the mechanisms and the magnitudes of the force that influence the vertical displacement resistance of the system? 2. Can the capacity at a specified deflection be reliably calculated using mechanics based equations? 3. What are the impacts of environmental exposure on the vertical displacement of furring strips attached directly through insulation back to a wood structure?

  3. Tunable Chern insulator with shaken optical lattices

    E-Print Network [OSTI]

    Albert Verdeny; Florian Mintert

    2015-04-16T23:59:59.000Z

    Driven optical lattices permit the engineering of effective dynamics with well-controllable tunneling properties. We describe the realization of a tunable a Chern insulator by driving particles on a shaken hexagonal lattice with optimally designed polychromatic driving forces. Its implementation does not require shallow lattices, which favors the study of strongly-correlated phases with non-trivial topology.

  4. A Novel Method for Transport and Cooling of a Muon Beam Based on Magnetic Insulation

    SciTech Connect (OSTI)

    Stratakis, Diktys; Gallardo, Juan C.; Palmer, Robert B. [Department of Physics, Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2010-11-04T23:59:59.000Z

    Unwanted field emission is a well known problem for high-gradient accelerating structures as it can cause damage and initiate breakdown. Recent experiments indicated that the deleterious effects of field-emission are greatly enhanced in the presence of external magnetic fields. In the context of designing a muon accelerator this imposes numerous constraints since rf cavities need to operate within strong magnetic fields in order to successfully transport the beam. Here, a novel design of a magnetically insulated cavity in which the walls are parallel to the magnetic field lines is presented. We show that with magnetic insulation, damage from field emission can be significantly suppressed. Effects of coil positioning errors on the cavity performance are discussed and the required magnetic field strength to achieve insulation is estimated. We present a conceptual design of a muon collider cooling lattice with magnetic insulated cavities and cross-check its performance to the one with pillbox cavities. Finally an experiment to test magnetic insulation is described.

  5. Specific features of the photoconductivity of semi-insulating cadmium telluride

    SciTech Connect (OSTI)

    Golubyatnikov, V. A.; Grigor’ev, F. I.; Lysenko, A. P., E-mail: aplysenko@hse.ru; Strogankova, N. I.; Shadov, M. B. [National Research University Higher School of Economics, Moscow Institute of Electronics and Mathematics (Russian Federation); Belov, A. G. [OAO GIREDMET State Research and Design Institute of the Rare-Metal Industry (Russian Federation)

    2014-12-15T23:59:59.000Z

    The effect of local illumination providing a high level of free-carrier injection on the conductivity of a sample of semi-insulating cadmium telluride and on the properties of ohmic contacts to the sample is studied. It is found that, irrespective of the illumination region, the contact resistance of ohmic contacts decreases and the concentration of majority carriers in the sample grows in proportion to the illumination intensity. It is shown that inherent heterogeneities in crystals of semi-insulating semiconductors can be studied by scanning with a light probe.

  6. Dielectric breakdown model for conductor-loaded and insulator-loaded composite materials P. Bergero,1

    E-Print Network [OSTI]

    Peruani, Fernando

    Dielectric breakdown model for conductor-loaded and insulator-loaded composite materials P. Bergero strength is highly desirable, and in the past years composite materials such as resin matrix filled- tors, and composites containing carbon black and titanium dioxide have recently been tested

  7. A design study on the scaling limit of ultra-thin silicon- on-insulator MOSFETs

    E-Print Network [OSTI]

    Lu, Wei-Yuan

    2007-01-01T23:59:59.000Z

    oxygen-ion implantation (SIMOX) and wafer bonding are particularly suitable for VLSI applications due to their compatibility with established CMOS processing technology.technologies for the formation of silicon-on-insulator structures. They are SIMOX (Separation by Implanted Oxygen),technology is illustrated in Fig. 4.19. A high dose of oxygen

  8. Intrinsic ultrathin topological insulators grown via molecular beam epitaxy characterized by in-situ angle resolved photoemission spectroscopy

    SciTech Connect (OSTI)

    Lee, J. J.; Vishik, I. M.; Ma, Y.; Shen, Z. X. [Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Geballe Laboratory for Advanced Materials, Department of Applied Physics, Stanford University, Stanford, California 94305 (United States); Schmitt, F. T.; Moore, R. G. [Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Geballe Laboratory for Advanced Materials, Department of Applied Physics, Stanford University, Stanford, California 94305 (United States)

    2012-07-02T23:59:59.000Z

    We demonstrate the capability of growing high quality ultrathin (10 or fewer quintuple layers) films of the topological insulators Bi{sub 2}Se{sub 3} and Bi{sub 2}Te{sub 3} using molecular beam epitaxy. Unlike previous growth techniques, which often pin the Fermi energy in the conduction band for ultrathin samples, our samples remain intrinsic bulk insulators. We characterize these films using in-situ angle resolved photoemission spectroscopy, which is a direct probe of bandstructure, and ex-situ atomic force microscopy. We find that the conduction band lies above the Fermi energy, indicating bulk insulating behavior with only the surface states crossing the Fermi energy. The use of a thermal cracker allows for more stoichiometric flux rates during growth, while still creating intrinsically doped films, paving the way for future improvements in growth of topological insulators.

  9. Pipeline system insulation: Thermal insulation and corrosion prevention. (Latest citations from the Rubber and Plastics Research Association database). Published Search

    SciTech Connect (OSTI)

    NONE

    1995-11-01T23:59:59.000Z

    The bibliography contains citations concerning thermal and corrosion insulation of pipeline systems used to transport liquids and gases. Topics include thermal aging of polyurethane used for foam heating pipes, extrusion film pipeline insulation materials and processes, flexible expanded nitrile rubber pipeline insulation with Class 1 fire rating, and underground fiberglass reinforced polyester insulated pipeline systems. Applications in solar heating systems; underground water, oil, and gas pipelines; interior hot and cold water lines under seawater; and chemical plant pipeline system insulation are included. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  10. Pipeline system insulation: Thermal insulation and corrosion prevention. (Latest citations from the Rubber and Plastics Research Association database). Published Search

    SciTech Connect (OSTI)

    NONE

    1995-01-01T23:59:59.000Z

    The bibliography contains citations concerning thermal and corrosion insulation of pipeline systems used to transport liquids and gases. Topics include thermal aging of polyurethane used for foam heating pipes, extrusion film pipeline insulation materials and processes, flexible expanded nitrile rubber pipeline insulation with Class 1 fire rating, and underground fiberglass reinforced polyester insulated pipeline systems. Applications in solar heating systems; underground water, oil, and gas pipelines; interior hot and cold water lines under seawater; and chemical plant pipeline system insulation are included. (Contains 250 citations and includes a subject term index and title list.)

  11. Pipeline system insulation: Thermal insulation and corrosion prevention. (Latest citations from the Rubber and Plastics Research Association database). Published Search

    SciTech Connect (OSTI)

    Not Available

    1994-05-01T23:59:59.000Z

    The bibliography contains citations concerning thermal and corrosion insulation of pipeline systems used to transport liquids and gases. Topics include thermal aging of polyurethane used for foam heating pipes, extrusion film pipeline insulation materials and processes, flexible expanded nitrile rubber pipeline insulation with Class 1 fire rating, and underground fiberglass reinforced polyester insulated pipeline systems. Applications in solar heating systems; underground water, oil, and gas pipelines; interior hot and cold water lines under seawater; and chemical plant pipeline system insulation are included. (Contains 250 citations and includes a subject term index and title list.)

  12. Apparatus for improving performance of electrical insulating structures

    DOE Patents [OSTI]

    Wilson, Michael J. (Modesto, CA); Goerz, David A. (Brentwood, CA)

    2002-01-01T23:59:59.000Z

    Removing the electrical field from the internal volume of high-voltage structures; e.g., bushings, connectors, capacitors, and cables. The electrical field is removed from inherently weak regions of the interconnect, such as between the center conductor and the solid dielectric, and places it in the primary insulation. This is accomplished by providing a conductive surface on the inside surface of the principal solid dielectric insulator surrounding the center conductor and connects the center conductor to this conductive surface. The advantage of removing the electric fields from the weaker dielectric region to a stronger area improves reliability, increases component life and operating levels, reduces noise and losses, and allows for a smaller compact design. This electric field control approach is currently possible on many existing products at a modest cost. Several techniques are available to provide the level of electric field control needed. Choosing the optimum technique depends on material, size, and surface accessibility. The simplest deposition method uses a standard electroless plating technique, but other metalization techniques include vapor and energetic deposition, plasma spraying, conductive painting, and other controlled coating methods.

  13. Affordable Window Insulation with R-10/inch Rating

    SciTech Connect (OSTI)

    Jenifer Marchesi Redouane Begag; Je Kyun Lee; Danny Ou; Jong Ho Sonn; George Gould; Wendell Rhine

    2004-10-15T23:59:59.000Z

    During the performance of contract DE-FC26-00-NT40998, entitled ''Affordable Window Insulation with R-10/inch Value'', research was conducted at Aspen Aerogels, Inc. to develop new transparent aerogel materials suitable for window insulation applications. The project requirements were to develop a formulation or multiple formulations that have high transparency (85-90%) in the visible region, are hydrophobic (will not opacify with exposure to water vapor or liquid), and have at least 2% resiliency (interpreted as recoverable 2% strain and better than 5% strain to failure in compression). Results from an unrelated project showed that silica aerogels covalently bonded to organic polymers exhibit excellent mechanical properties. At the outset of this project, we believed that such a route is the best to improve mechanical properties. We have applied Design of Experiment (DOE) techniques to optimize formulations including both silica aerogels and organically modified silica aerogels (''Ormosils''). We used these DOE results to optimize formulations around the local/global optimization points. This report documents that we succeeded in developing a number of formulations that meet all of the stated criteria. We successfully developed formulations utilizing a two-step approach where the first step involves acid catalyzed hydrolysis and the second step involves base catalyzed condensation to make the gels. The gels were dried using supercritical CO{sub 2} and we were able to make 1 foot x 1 foot x 0.5 inch panels that met the criteria established.

  14. Particle trap for compressed gas insulated transmission systems

    DOE Patents [OSTI]

    Cookson, A.H.

    1984-04-26T23:59:59.000Z

    A particle trap is provided for gas insulated transmission lines having a central high voltage conductor supported within an outer coaxial conductive sheath by a dielectric support member. A cavity between the inner conductor and outer sheath is filled with a dielectric insulating gas. A cone-like particle deflector, mounted to the inner conductor, deflects moving particles away from the support member, to radially outer portions of the cavity. A conductive shield is disposed adjacent the outer sheath to form a field-free region in radially outer portions of the cavity, between the shield and the sheath. Particles traveling along the cavity are deflected by the cone-like deflector into the field-free region where they are held immobile. In a vertical embodiment, particles enter the field-free region through an upper end of a gap formed between shield and sheath members. In a horizontal embodiment, the deflector cone has a base which is terminated radially internally of the shield. Apertures in the shield located adjacent the deflector allow passage of deflected particles into the field-free region. The dielectric support member is thereby protected from contaminating particles that may otherwise come to rest thereon.

  15. Particle trap for compressed gas insulated transmission systems

    DOE Patents [OSTI]

    Cookson, Alan H. (Pittsburgh, PA)

    1985-01-01T23:59:59.000Z

    A particle trap is provided for gas insulated transmission lines having a central high voltage conductor supported within an outer coaxial conductive sheath by a dielectric support member. A cavity between the inner conductor and outer sheath is filled with a dielectric insulating gas. A cone-like particle deflector, mounted to the inner conductor, deflects moving particles away from the support member, to radially outer portions of the cavity. A conductive shield is disposed adjacent the outer sheath to form a field-free region in radially outer portions of the cavity, between the shield and the sheath. Particles traveling along the cavity are deflected by the cone-like deflector into the field-free region where they are held immobile. In a vertical embodiment, particles enter the field-free region through an upper end of a gap formed between shield and sheath members. In a horizontal embodiment, the deflector cone has a base which is terminated radially internally of the shield. Apertures in the shield located adjacent the deflector allow passage of deflected particles into the field-free region. The dielectric support member is thereby protected from contaminating particles that may otherwise come to rest thereon.

  16. Apparatus for improving performance of electrical insulating structures

    DOE Patents [OSTI]

    Wilson, Michael J.; Goerz, David A.

    2004-08-31T23:59:59.000Z

    Removing the electrical field from the internal volume of high-voltage structures; e.g., bushings, connectors, capacitors, and cables. The electrical field is removed from inherently weak regions of the interconnect, such as between the center conductor and the solid dielectric, and places it in the primary insulation. This is accomplished by providing a conductive surface on the inside surface of the principal solid dielectric insulator surrounding the center conductor and connects the center conductor to this conductive surface. The advantage of removing the electric fields from the weaker dielectric region to a stronger area improves reliability, increases component life and operating levels, reduces noise and losses, and allows for a smaller compact design. This electric field control approach is currently possible on many existing products at a modest cost. Several techniques are available to provide the level of electric field control needed. Choosing the optimum technique depends on material, size, and surface accessibility. The simplest deposition method uses a standard electroless plating technique, but other metalization techniques include vapor and energetic deposition, plasma spraying, conductive painting, and other controlled coating methods.

  17. Multiterminal Conductance of a Floquet Topological Insulator

    E-Print Network [OSTI]

    L. E. F. Foa Torres; P. M. Perez-Piskunow; C. A. Balseiro; G. Usaj

    2014-09-08T23:59:59.000Z

    We report on simulations of the dc conductance and quantum Hall response of a Floquet topological insulator using Floquet scattering theory. Our results reveal that laser-induced edge states in graphene lead to quantum Hall plateaus once imperfect matching with the non-illuminated leads is lessened. But the magnitude of the Hall plateaus is not directly related to the number and chirality of all the edge states at a given energy as usual. Instead, the plateaus are dominated only by those edge states adding to the dc density of states. Therefore, the dc quantum Hall conductance of a Floquet topological insulator is not directly linked to topological invariants of the full the Floquet bands.

  18. Electric-Magnetic Duality and Topological Insulators

    E-Print Network [OSTI]

    Andreas Karch

    2009-10-03T23:59:59.000Z

    We work out the action of the SL(2,Z) electric-magnetic duality group for an insulator with a non-trivial permittivity, permeability and theta-angle. This theory has recently been proposed to be the correct low-energy effective action for topological insulators. As applications, we give manifestly SL(2,Z) covariant expressions for the Faraday rotation at orthogonal incidence at the interface of two such materials, as well as for the induced magnetic and electric charges, slightly clarifying the meaning of expressions previously derived in the literature. We also use electric-magnetic duality to find a gravitational dual for a strongly coupled version of this theory using the AdS/CFT correspondence.

  19. Fractional topological insulators in three dimensions

    E-Print Network [OSTI]

    Joseph Maciejko; Xiao-Liang Qi; Andreas Karch; Shou-Cheng Zhang

    2010-11-14T23:59:59.000Z

    Topological insulators can be generally defined by a topological field theory with an axion angle theta of 0 or pi. In this work, we introduce the concept of fractional topological insulator defined by a fractional axion angle and show that it can be consistent with time reversal (T) invariance if ground state degeneracies are present. The fractional axion angle can be measured experimentally by the quantized fractional bulk magnetoelectric polarization P_3, and a `halved' fractional quantum Hall effect on the surface with Hall conductance of the form (p/q)(e^2/2h) with p,q odd. In the simplest of these states the electron behaves as a bound state of three fractionally charged `quarks' coupled to a deconfined non-Abelian SU(3) `color' gauge field, where the fractional charge of the quarks changes the quantization condition of P_3 and allows fractional values consistent with T-invariance.

  20. Electric-Magnetic Duality and Topological Insulators

    SciTech Connect (OSTI)

    Karch, A. [Department of Physics, University of Washington, Seattle, Washington 98195-1560 (United States)

    2009-10-23T23:59:59.000Z

    We work out the action of the SL(2,Z) electric-magnetic duality group for an insulator with a nontrivial permittivity, permeability, and theta angle. This theory has recently been proposed to be the correct low-energy effective action for topological insulators. As applications, we give manifestly SL(2,Z) covariant expressions for the Faraday rotation at orthogonal incidence at the interface of two such materials, as well as for the induced magnetic and electric charges, slightly clarifying the meaning of expressions previously derived in the literature. We also use electric-magnetic duality to find a gravitational dual for a strongly coupled version of this theory using the gauge/gravity correspondence.

  1. Fractional Topological Insulators in Three Dimensions

    SciTech Connect (OSTI)

    Maciejko, Joseph; Zhang Shoucheng [Department of Physics, Stanford University, Stanford, California 94305 (United States); Qi Xiaoliang [Microsoft Research, Station Q, Elings Hall, University of California, Santa Barbara, California 93106 (United States); Department of Physics, Stanford University, Stanford, California 94305 (United States); Karch, Andreas [Department of Physics, University of Washington, Seattle, Washington 98195-1560 (United States)

    2010-12-10T23:59:59.000Z

    Topological insulators can be generally defined by a topological field theory with an axion angle {theta} of 0 or {pi}. In this work, we introduce the concept of fractional topological insulator defined by a fractional axion angle and show that it can be consistent with time reversal T invariance if ground state degeneracies are present. The fractional axion angle can be measured experimentally by the quantized fractional bulk magnetoelectric polarization P{sub 3}, and a 'halved' fractional quantum Hall effect on the surface with Hall conductance of the form {sigma}{sub H}=(p/q)(e{sup 2}/2h) with p, q odd. In the simplest of these states the electron behaves as a bound state of three fractionally charged 'quarks' coupled to a deconfined non-Abelian SU(3) 'color' gauge field, where the fractional charge of the quarks changes the quantization condition of P{sub 3} and allows fractional values consistent with T invariance.

  2. Transgression field theory for interacting topological insulators

    E-Print Network [OSTI]

    Aç?k, Özgür

    2013-01-01T23:59:59.000Z

    We consider effective topological field theories of quantum Hall systems and time-reversal invariant topological insulators that are Chern-Simons and BF field theories. The edge states of these systems are related to the gauge invariance of the effective actions. For the edge states at the interface of two topological insulators, transgression field theory is proposed as a gauge invariant effective action. Transgression actions of Chern-Simons theories for (2+1)D and (4+1)D and BF theories for (3+1)D are constructed. By using transgression actions, the edge states are written in terms of the bulk connections of effective Chern-Simons and BF theories.

  3. Apparatus for insulating windows and the like

    DOE Patents [OSTI]

    Mitchell, Robert A. (R.D. #1, Box 462-A, Voorheesville, NY 12186)

    1984-01-01T23:59:59.000Z

    Apparatus for insulating window openings through walls and the like includes a thermal shutter, a rail for mounting the shutter adjacent to the window opening and a coupling for connecting the shutter to the rail. The thermal shutter includes an insulated panel adhered to frame members which surround the periphery of the panel. The frame members include a hard portion for providing the frame and a soft portion for providing a seal with that portion of the wall adjacent to the periphery of the opening. The coupling means is preferably integral with the attachment rail. According to a preferred embodiment, the coupling means includes a continuous hinge of reduced thickness. The thermal shutter can be permanently attached, hinged, bi-folded, or sliding with respect to the window and wall. A distribution method is to market the apparatus in "kit" form.

  4. Contaminant trap for gas-insulated apparatus

    DOE Patents [OSTI]

    Adcock, James L. (Knoxville, TN); Pace, Marshall O. (Knoxville, TN); Christophorou, Loucas G. (Oak Ridge, TN)

    1984-01-01T23:59:59.000Z

    A contaminant trap for a gas-insulated electrical conductor is provided. A resinous dielectric body such as Kel-F wax, grease or other sticky polymeric or oligomeric compound is disposed on the inside wall of the outer housing for the conductor. The resinous body is sufficiently sticky at ambient temperatures to immobilize contaminant particles in the insulating gas on the exposed surfaces thereof. An electric resistance heating element is disposed in the resinous body to selectively raise the temperature of the resinous body to a molten state so that the contaminant particles collected on the surface of the body sink into the body so that the surface of the resinous body is renewed to a particle-less condition and, when cooled, returns to a sticky collecting surface.

  5. Molecular Beam Epitaxial Growth of Bi2Te3 and Sb2Te3 Topological Insulators on GaAs (111) Substrates: A Potential Route to Fabricate Topological Insulator p-n Junction

    E-Print Network [OSTI]

    Zhaoquan Zeng; Timothy A. Morgan; Dongsheng Fan; Chen Li; Yusuke Hirono; Xian Hu; Yanfei Zhao; Joon Sue Lee; Zhiming M. Wang; Jian Wang; Shuiqing Yu; Michael E. Hawkridge; Mourad Benamara; Gregory J. Salamo

    2013-03-11T23:59:59.000Z

    High quality Bi2Te3 and Sb2Te3 topological insulators films were epitaxially grown on GaAs (111) substrate using solid source molecular beam epitaxy. Their growth and behavior on both vicinal and non-vicinal GaAs (111) substrates were investigated by reflection high-energy electron diffraction, atomic force microscopy, x-ray diffraction, and high resolution transmission electron microscopy. It is found that non-vicinal GaAs (111) substrate is better than a vicinal substrate to provide high quality Bi2Te3 and Sb2Te3 films. Hall and magnetoresistance measurements indicate that p type Sb2Te3 and n type Bi2Te3 topological insulator films can be directly grown on a GaAs (111) substrate, which may pave a way to fabricate topological insulator p-n junction on the same substrate, compatible with the fabrication process of present semiconductor optoelectronic devices.

  6. Widespread spin polarization effects in photoemission from topological insulators

    SciTech Connect (OSTI)

    Jozwiak, C.; Chen, Y. L.; Fedorov, A. V.; Analytis, J. G.; Rotundu, C. R.; Schmid, A. K.; Denlinger, J. D.; Chuang, Y.-D.; Lee, D.-H.; Fisher, I. R.; Birgeneau, R. J.; Shen, Z.-X.; Hussain, Z.; Lanzara, A.

    2011-06-22T23:59:59.000Z

    High-resolution spin- and angle-resolved photoemission spectroscopy (spin-ARPES) was performed on the three-dimensional topological insulator Bi{sub 2}Se{sub 3} using a recently developed high-efficiency spectrometer. The topological surface state's helical spin structure is observed, in agreement with theoretical prediction. Spin textures of both chiralities, at energies above and below the Dirac point, are observed, and the spin structure is found to persist at room temperature. The measurements reveal additional unexpected spin polarization effects, which also originate from the spin-orbit interaction, but are well differentiated from topological physics by contrasting momentum and photon energy and polarization dependencies. These observations demonstrate significant deviations of photoelectron and quasiparticle spin polarizations. Our findings illustrate the inherent complexity of spin-resolved ARPES and demonstrate key considerations for interpreting experimental results.

  7. Excavationless Exterior Foundation Insulation Exploratory Study

    SciTech Connect (OSTI)

    Mosiman, G.; Wagner, R.; Schirber, T.

    2013-02-01T23:59:59.000Z

    The key objective of this exploratory study was to investigate the feasibility of the development or adoption of technologies that would enable a large percentage of existing homes in cold climates to apply a combination 'excavationless' soil removal process with appropriate insulation and water management on the exterior of existing foundations at a low cost. Our approach was to explore existing excavation and material technologies and systems to discover whether potential successful combinations existed.

  8. Witten effect in a crystalline topological insulator

    SciTech Connect (OSTI)

    Rosenberg, G.; Franz, M. [Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, V6T 1Z1 (Canada)

    2010-07-15T23:59:59.000Z

    It has been noted a long time ago that a term of the form theta(e{sup 2}/2pih)Bcentre dotE may be added to the standard Maxwell Lagrangian without modifying the familiar laws of electricity and magnetism. theta is known to particle physicists as the 'axion' field and whether or not it has a nonzero expectation value in vacuum remains a fundamental open question of the standard model. A key manifestation of the axion term is the Witten effect: a unit magnetic monopole placed inside a medium with thetanot =0 is predicted to bind a (generally fractional) electric charge -e(theta/2pi+n) with n integer. Here we conduct a test of the Witten effect based on the recently established fact that the axion term with theta=pi emerges naturally in the description of the electromagnetic response of a class of crystalline solids called topological insulators--materials distinguished by strong spin-orbit coupling and nontrivial band structures. Using a simple physical model for a topological insulator we demonstrate the existence of a fractional charge bound to a monopole by an explicit numerical calculation. We also propose a scheme for generating an 'artificial' magnetic monopole in a topological insulator film that may be used to facilitate an experimental test of Witten's prediction.

  9. Topological insulators with arbitrarily tunable entanglement

    E-Print Network [OSTI]

    J. C. Budich; J. Eisert; E. J. Bergholtz

    2014-05-15T23:59:59.000Z

    We elucidate how Chern and topological insulators fulfill an area law for the entanglement entropy. By explicit construction of a family of lattice Hamiltonians, we are able to demonstrate that the area law contribution can be tuned to an arbitrarily small value, but is topologically protected from vanishing exactly. We prove this by introducing novel methods to bound entanglement entropies from correlations using perturbation bounds, drawing intuition from ideas of quantum information theory. This rigorous approach is complemented by an intuitive understanding in terms of entanglement edge states. These insights have a number of important consequences: The area law has no universal component, no matter how small, and the entanglement scaling cannot be used as a faithful diagnostic of topological insulators. This holds for all Renyi entropies which uniquely determine the entanglement spectrum which is hence also non-universal. The existence of arbitrarily weakly entangled topological insulators furthermore opens up possibilities of devising correlated topological phases in which the entanglement entropy is small and which are thereby numerically tractable, specifically in tensor network approaches.

  10. Smoldering combustion hazards of thermal insulation materials

    SciTech Connect (OSTI)

    Ohlemiller, T.J.; Rogers, F.E.

    1980-07-01T23:59:59.000Z

    Work on the smolder ignitability in cellulosic insulation and on thermal analytical characterization of the oxidation of this material is presented. Thermal analysis (TGA and DSC) shows that both retarded and unretarded cellulosic insulation oxidizes in two overall stages, both of which are exothermic. The second stage (oxidation of the char left as a residue of the first stage) is much more energetic on a unit mass basis than the first. However, kinetics and a sufficient exothermicity make the first stage responsible for ignition in most realistic circumstances. Existing smolder retardants such as boric acid have their major effect on the kinetics of the second oxidation stage and thus produce only a rather small (20/sup 0/C) increase in smolder ignition temperature. Several simplified analogs of attic insulations have been tested to determine the variability of minimum smolder ignition temperature. These employed planar or tubular constant temperature heat sources in a thermal environment quite similar to a realistic attic application. Go/no-go tests provided the borderline (minimum) ignition temperature for each configuration. The wide range (150/sup 0/C) of minimum ignition temperatures confirmed the predominant dependence of smolder ignition on heat flow geometry. Other factors (bulk density, retardants) produced much less effect on ignitability.

  11. Humidity effects on wire insulation breakdown strength.

    SciTech Connect (OSTI)

    Appelhans, Leah

    2013-08-01T23:59:59.000Z

    Methods for the testing of the dielectric breakdown strength of insulation on metal wires under variable humidity conditions were developed. Two methods, an ASTM method and the twisted pair method, were compared to determine if the twisted pair method could be used for determination of breakdown strength under variable humidity conditions. It was concluded that, although there were small differences in outcomes between the two testing methods, the non-standard method (twisted pair) would be appropriate to use for further testing of the effects of humidity on breakdown performance. The dielectric breakdown strength of 34G copper wire insulated with double layer Poly-Thermaleze/Polyamide-imide insulation was measured using the twisted pair method under a variety of relative humidity (RH) conditions and exposure times. Humidity at 50% RH and below was not found to affect the dielectric breakdown strength. At 80% RH the dielectric breakdown strength was significantly diminished. No effect for exposure time up to 140 hours was observed at 50 or 80%RH.

  12. Correctly specify insulation for process equipment and piping

    SciTech Connect (OSTI)

    Allen, C. [Raytheon Engineers and Constructors, Birmingham, AL (United States)

    1997-05-01T23:59:59.000Z

    Insulation serves as a thermal barrier to resist the flow of heat. When insulation is installed over piping or equipment to minimize heat losses, the insulation is categorized as heat conservation. Software programs for determining heat losses are based on ASTM C 680. If heat conservation insulation is calculated to determine the most cost-effective thickness for piping or equipment, then the insulation is categorized as economic insulation. Methods for manually determining economic thicknesses using various graphs and precalculated charts are given in Turner and Malloy. However, modern software programs available from industrial associations calculate economic thicknesses based on after-tax annual costs. Costs associated with owning insulation are expressed on an equivalent uniform annual cost basis. The thickness with the lowest annual cost is reported as the economic thickness. Some of the economic data needed to calculate economic thicknesses are fuel cost, depreciation period, annual fuel inflation rate, annual hours of operation, return on investment, effective income tax rate, annual insulation maintenance costs, and installed costs. To obtain accurate economical thicknesses, it is best to solicit installed costs from a local contractor likely to bid on the work. This paper covers the most suitable insulation materials for certain applications, the most economic material and thickness to use, and how the total insulation system should be designed.

  13. Building America Webinar: High Performance Enclosure Strategies...

    Energy Savers [EERE]

    Webinar: High Performance Enclosure Strategies: Part II, New Construction - August 13, 2014 - Cladding Attachment Over Thick Exterior Rigid Insulation Building America Webinar:...

  14. Affordable Cold Climate Infill Housing with Hybrid Insulation Approach, Wyandotte, Michigan (Fact Sheet)

    SciTech Connect (OSTI)

    Metzger, C.; Lukachko, A.; Grin, A.; Bergey, D.

    2013-11-01T23:59:59.000Z

    Even builders who are relatively new to energy-efficient construction can consistently reach a target whole house airtightness of 1.5 air changes per hour at 50 Pascals (ACH50) with high R-value enclosures that use a hybrid insulation approach. The City of Wyandotte, Michigan, started a construction program in 2010 to build affordable, energy-efficient homes on lots in existing neighborhoods. A goal of the program was to engage local builders in energy-efficient construction and be able to deliver the new houses for less than $100/ft2. By the end of 2012, approximately 25 new houses were built by five local builders under this program. To help builders consistently achieve the airtightness target, a local architect worked with researchers from Building Science Corporation, a U.S. Department of Energy Building America team, to develop a technology specification with several key pieces. A high R-value wall and roof assembly made use of 2 ?6 advanced framing and a hybrid insulation approach that included insulating sheathing to control thermal bridging and closed cell spray polyurethane foam insulation (ccSPF) for its airtightness and vapor control benefits. This approach allows the air barrier to be completed and tested before any finishing work occurs, ensuring that problems are spotted and corrected early in the construction process.

  15. Thermal balance of a wall with PCM-enhanced thermal insulation

    SciTech Connect (OSTI)

    Kosny, Jan [ORNL] [ORNL; Kossecka, Elizabeth [Institute of Fundamental Technological Research, Polish Academy of Sciences] [Institute of Fundamental Technological Research, Polish Academy of Sciences; Williams, Teresa [ORNL] [ORNL

    2010-01-01T23:59:59.000Z

    ABSTRACT: PCM insulation mixtures function as lightweight thermal mass components. It is expected that these types of dynamic insulation systems will contribute to the objective of reducing energy use in buildings. In this paper, dynamic thermal properties of a material in which phase hange occurs are analyzed, using the temperature-dependent specific heat model. Integral formula for the total heat flow in finite time interval, across the surface of a slab of the phase change material, was derived. Simulations have been performed to analyze heat transfer through a light-weight wall assembly with PCM-enhanced insulation, in different external climate thermal conditions. Results of simulations indicate that for cyclic processes, the effect of PCM in an insulation layer results rather in time shifting of the heat flux extreme values than in reduction of the total heat flow. The heat gains maxima, resulting in high cooling loads, are shifted in time by about two hours and reduced about 15% to 30% for not very high external sol-air temperatures.

  16. Influence Of Three Dynamic Predictive Clothing Insulation Models On Building Energy Use, HVAC Sizing And Thermal Comfort

    E-Print Network [OSTI]

    Schiavon, Stefano; Lee, Kwang Ho

    2013-01-01T23:59:59.000Z

    Predictive Clothing Insulation Models based on Outdoor AirPREDICTIVE CLOTHING INSULATION MODELS ON BUILDING ENERGYthat the clothing insulation is equal to a constant value of

  17. Compact gas-insulated transformer. Fourteenth quarterly report

    SciTech Connect (OSTI)

    Not Available

    1983-08-01T23:59:59.000Z

    Objective is to develop a compact, more efficient, quieter transformer which does not rely on mineral oil insulation. Compressed SF/sub 6/ is used as the external insulation and polymer film as the insulation between turns. A separate liquid cooling system is also provided. This document reports progress made in design, mechanical, dielectric, short circuit, thermal, materials, prototype, accessories, commercialization, and system studies. (DLC)

  18. Shaking the bonds: Atomic vibrations drive insulator to metal...

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

    phase stability for more than 50 years. When heated to just above room temperature, the material undergoes an abrupt transformation from an electrical insulator to a conducting...

  19. Electrical spin injection in 2D semiconductors and topological insulators

    SciTech Connect (OSTI)

    Golub, L. E.; Ivchenko, E. L. [Ioffe Physical-Technical Institute of the Russian Academy of Sciences, St. Petersburg (Russian Federation)

    2013-12-04T23:59:59.000Z

    We have developed a theory of spin orientation by electric current in 2D semiconductors. It is shown that the spin depends on the relation between the energy and spin relaxation times and can vary by a factor of two for the limiting cases of fast and slow energy relaxation. For symmetrically-doped (110)-grown semiconductor quantum wells the effect of current-induced spin orientation is shown to exist due to random spatial variation of the Rashba spin-orbit splitting. We demonstrate that the spin depends strongly on the correlation length of this random spin-orbit field. We calculate the spin orientation degree in two-dimensional topological insulators. In high electric fields when the “streaming” regime is realized, the spin orientation degree weakly depends on the electric field and can reach values about 5%.

  20. Gas-controlled dynamic vacuum insulation with gas gate

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1994-06-07T23:59:59.000Z

    Disclosed is a dynamic vacuum insulation comprising sidewalls enclosing an evacuated chamber and gas control means for releasing hydrogen gas into a chamber to increase gas molecule conduction of heat across the chamber and retrieving hydrogen gas from the chamber. The gas control means includes a metal hydride that absorbs and retains hydrogen gas at cooler temperatures and releases hydrogen gas at hotter temperatures; a hydride heating means for selectively heating the metal hydride to temperatures high enough to release hydrogen gas from the metal hydride; and gate means positioned between the metal hydride and the chamber for selectively allowing hydrogen to flow or not to flow between said metal hydride and said chamber. 25 figs.

  1. Gas-controlled dynamic vacuum insulation with gas gate

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO); Potter, Thomas F. (Denver, CO)

    1994-06-07T23:59:59.000Z

    Disclosed is a dynamic vacuum insulation comprising sidewalls enclosing an evacuated chamber and gas control means for releasing hydrogen gas into a chamber to increase gas molecule conduction of heat across the chamber and retrieving hydrogen gas from the chamber. The gas control means includes a metal hydride that absorbs and retains hydrogen gas at cooler temperatures and releases hydrogen gas at hotter temperatures; a hydride heating means for selectively heating the metal hydride to temperatures high enough to release hydrogen gas from the metal hydride; and gate means positioned between the metal hydride and the chamber for selectively allowing hydrogen to flow or not to flow between said metal hydride and said chamber.

  2. Irradiation imposed degradation of the mechanical and electrical properties of electrical insulation for future accelerator magnets

    SciTech Connect (OSTI)

    Polinski, J.; Chorowski, M.; Bogdan, P.; Strychalski, M. [Wroclaw University of Technology, Wyb. Wyspianskiego 27, 50-370 Wroclaw (Poland); Rijk, G. de [European Organization for Nuclear Research CERN, 1211 Geneva (Switzerland)

    2014-01-27T23:59:59.000Z

    Future accelerators will make extensive use of superconductors made of Nb{sub 3}Sn, which allows higher magnetic fields than NbTi. However, the wind-and-react technology of Nb{sub 3}Sn superconducting magnet production makes polyimide Kapton® non applicable for the coils' electrical insulation. A Nb{sub 3}Sn technology compatible insulation material should be characterized by high radiation resistivity, good thermal conductivity, and excellent mechanical properties. Candidate materials for the electrical insulation of future accelerator's magnet coils have to be radiation certified with respect to potential degradation of their electrical, thermal, and mechanical properties. This contribution presents procedures and results of tests of the electrical and mechanical properties of DGEBA epoxy + D400 hardener, which is one of the candidates for the electrical insulation of future magnets. Two test sample types have been used to determine the material degradation due to irradiation: a untreated one (unirradiated) and irradiated at 77 K with 11 kGy/min intense, 4MeV energy electrons beam to a total dose of 50 MGy.

  3. Topological insulators with SU(2) Landau levels

    E-Print Network [OSTI]

    Yi Li; Shou-Cheng Zhang; Congjun Wu

    2013-10-23T23:59:59.000Z

    We construct continuum models of 3D and 4D topological insulators by coupling spin-1/2 fermions to an SU(2) background gauge field, which is equivalent to a spatially dependent spin-orbit coupling. Higher dimensional generalizations of flat Landau levels are obtained in the Landau-like gauge. The 2D helical Dirac modes with opposite helicities and 3D Weyl modes with opposite chiralities are spatially separated along the third and fourth dimensions, respectively. Stable 2D helical Fermi surfaces and 3D chiral Fermi surfaces appear on open boundaries, respectively. The charge pumping in 4D Landau level systems shows quantized 4D quantum Hall effect.

  4. Möbius Graphene Strip as Topological Insulator

    E-Print Network [OSTI]

    Z. L. Guo; Z. R. Gong; H. Dong; C. P. Sun

    2009-06-09T23:59:59.000Z

    We study the electronic properties of M\\"{o}bius graphene strip with a zigzag edge. We show that such graphene strip behaves as a topological insulator with a gapped bulk and a robust metallic surface, which enjoys some features due to its nontrivial topology of the spatial configuration, such as the existence of edge states and the non-Abelian induced gauge field. We predict that the topological properties of the M\\"{o}bius graphene strip can be experimentally displayed by the destructive interference in the transmission spectrum, and the robustness of edge states under certain perturbations.

  5. Novel metals and insulators from holography

    E-Print Network [OSTI]

    Aristomenis Donos; Jerome P. Gauntlett

    2014-06-02T23:59:59.000Z

    Using simple holographic models in $D=4$ spacetime dimensions we construct black hole solutions dual to $d=3$ CFTs at finite charge density with a Q-lattice deformation. At zero temperature we find new ground state solutions with broken translation invariance, either in one or both spatial directions, which exhibit insulating or metallic behaviour depending on the parameters of the holographic theory. For low temperatures and small frequencies, the real part of the optical conductivity has a power-law behaviour, with the exponent determined by the ground state. We also obtain an expression for the the DC conductivity at finite temperature in terms of horizon data of the black hole solutions.

  6. Holographic Metals and Insulators with Helical Symmetry

    E-Print Network [OSTI]

    Aristomenis Donos; Blaise Goutéraux; Elias Kiritsis

    2014-09-17T23:59:59.000Z

    Homogeneous, zero temperature scaling solutions with Bianchi VII spatial geometry are constructed in Einstein-Maxwell-Dilaton theory. They correspond to quantum critical saddle points with helical symmetry at finite density. Assuming $AdS_{5}$ UV asymptotics, the small frequency/(temperature) dependence of the AC/(DC) electric conductivity along the director of the helix are computed. A large class of insulating and conducting anisotropic phases is found, as well as isotropic, metallic phases. Conduction can be dominated by dissipation due to weak breaking of translation symmetry or by a quantum critical current.

  7. Types of Insulation | Department of Energy

    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),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassiveSubmittedStatusButlerTransportation6/14/11 Page 1Two NovelTwoTypes ofInsulation

  8. Insulating conduction in Sn/Si(111): Possibility of a Mott insulating ground state and metallization/localization induced by carrier doping

    E-Print Network [OSTI]

    Hasegawa, Shuji

    Insulating conduction in Sn/Si(111): Possibility of a Mott insulating ground state measurements. The temperature dependence of the surface-state conductivity showed an insulating behavior from is insulating with a very small energy gap, which is consistent with a recent theoretical study G. Profeta and E

  9. Electrical Transport of Topological Insulator-Bi2Se3 and Thermoelectric Properties of Graphene

    E-Print Network [OSTI]

    WEI, PENG

    2011-01-01T23:59:59.000Z

    Hall effect and topological insulators. Phys Today Klitzing,L. & Mele, E. J. Topological insulators in three dimensions.Zhang, H. J. et al. Topological insulators in Bi 2 Se 3 , Bi

  10. Scattering of Dirac Fermions in Barrier Geometries on the Surface of Topological Insulators

    E-Print Network [OSTI]

    Torquato, Salvatore

    Scattering of Dirac Fermions in Barrier Geometries on the Surface of Topological Insulators Lindsay Fleischer 1 Introduction Predicted theoretically and discovered experimentally, the topological insulators topological in- sulators and the trivial insulating vacuum have wavefunctions which are not smoothly

  11. Polarization dependent photocurrents in thin films of the topological insulator Bi?Se?

    E-Print Network [OSTI]

    Lau, Claudia (Claudia M.)

    2012-01-01T23:59:59.000Z

    Topological insulators are a new class of three-dimensional quantum materials whose interior or bulk is an insulator but whose surface is a conductor. Bi?Se? is a prototypical topological insulator that physicists at MIT ...

  12. Topological Field Theory of Time-Reversal Invariant Insulators

    E-Print Network [OSTI]

    Xiao-Liang Qi; Taylor Hughes; Shou-Cheng Zhang

    2008-02-24T23:59:59.000Z

    We show that the fundamental time reversal invariant (TRI) insulator exists in 4+1 dimensions, where the effective field theory is described by the 4+1 dimensional Chern-Simons theory and the topological properties of the electronic structure is classified by the second Chern number. These topological properties are the natural generalizations of the time reversal breaking (TRB) quantum Hall insulator in 2+1 dimensions. The TRI quantum spin Hall insulator in 2+1 dimensions and the topological insulator in 3+1 dimension can be obtained as descendants from the fundamental TRI insulator in 4+1 dimensions through a dimensional reduction procedure. The effective topological field theory, and the $Z_2$ topological classification for the TRI insulators in 2+1 and 3+1 dimensions are naturally obtained from this procedure. All physically measurable topological response functions of the TRI insulators are completely described by the effective topological field theory. Our effective topological field theory predicts a number of novel and measurable phenomena, the most striking of which is the topological magneto-electric effect, where an electric field generates a magnetic field in the same direction, with an universal constant of proportionality quantized in odd multiples of the fine structure constant $\\alpha=e^2/\\hbar c$. Finally, we present a general classification of all topological insulators in various dimensions, and describe them in terms of a unified topological Chern-Simons field theory in phase space.

  13. Bosonic Topological Insulators and Paramagnets: a view from cobordisms

    E-Print Network [OSTI]

    Anton Kapustin

    2014-11-14T23:59:59.000Z

    We classify Bosonic Topological Insulators and Paramagnets in DTopological Insulator protected by time-reversal symmetry whose surface admits an all-fermion topologically ordered state. For D=4 there is a unique "beyond group cohomology" phase. It is protected by gravitational anomalies of the boundary theory and is stable without any additional symmetry.

  14. Topological Field Theory of Time-Reversal Invariant Insulators

    SciTech Connect (OSTI)

    Qi, Xiao-Liang; Hughes, Taylor; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

    2010-03-19T23:59:59.000Z

    We show that the fundamental time reversal invariant (TRI) insulator exists in 4 + 1 dimensions, where the effective field theory is described by the 4 + 1 dimensional Chern-Simons theory and the topological properties of the electronic structure is classified by the second Chern number. These topological properties are the natural generalizations of the time reversal breaking (TRB) quantum Hall insulator in 2 + 1 dimensions. The TRI quantum spin Hall insulator in 2 + 1 dimensions and the topological insulator in 3 + 1 dimension can be obtained as descendants from the fundamental TRI insulator in 4 + 1 dimensions through a dimensional reduction procedure. The effective topological field theory, and the Z{sub 2} topological classification for the TRI insulators in 2+1 and 3+1 dimensions are naturally obtained from this procedure. All physically measurable topological response functions of the TRI insulators are completely described by the effective topological field theory. Our effective topological field theory predicts a number of novel and measurable phenomena, the most striking of which is the topological magneto-electric effect, where an electric field generates a magnetic field in the same direction, with an universal constant of proportionality quantized in odd multiples of the fine structure constant {alpha} = e{sup 2}/hc. Finally, we present a general classification of all topological insulators in various dimensions, and describe them in terms of a unified topological Chern-Simons field theory in phase space.

  15. Process for manufacturing hollow fused-silica insulator cylinder

    DOE Patents [OSTI]

    Sampayan, Stephen E. (Manteca, CA); Krogh, Michael L. (Lee's Summit, MO); Davis, Steven C. (Lee's Summit, MO); Decker, Derek E. (Discovery Bay, CA); Rosenblum, Ben Z. (Overland Park, KS); Sanders, David M. (Livermore, CA); Elizondo-Decanini, Juan M. (Albuquerque, NM)

    2001-01-01T23:59:59.000Z

    A method for building hollow insulator cylinders that can have each end closed off with a high voltage electrode to contain a vacuum. A series of fused-silica round flat plates are fabricated with a large central hole and equal inside and outside diameters. The thickness of each is related to the electron orbit diameter of electrons that escape the material surface, loop, and return back. Electrons in such electron orbits can support avalanche mechanisms that result in surface flashover. For example, the thickness of each of the fused-silica round flat plates is about 0.5 millimeter. In general, the thinner the better. Metal, such as gold, is deposited onto each top and bottom surface of the fused-silica round flat plates using chemical vapor deposition (CVD). Eutectic metals can also be used with one alloy constituent on the top and the other on the bottom. The CVD, or a separate diffusion step, can be used to defuse the deposited metal deep into each fused-silica round flat plate. The conductive layer may also be applied by ion implantation or gas diffusion into the surface. The resulting structure may then be fused together into an insulator stack. The coated plates are aligned and then stacked, head-to-toe. Such stack is heated and pressed together enough to cause the metal interfaces to fuse, e.g., by welding, brazing or eutectic bonding. Such fusing is preferably complete enough to maintain a vacuum within the inner core of the assembled structure. A hollow cylinder structure results that can be used as a core liner in a dielectric wall accelerator and as a vacuum envelope for a vacuum tube device where the voltage gradients exceed 150 kV/cm.

  16. Correlated topological insulators and the fractional magnetoelectric effect

    SciTech Connect (OSTI)

    Swingle, B.; Barkeshli, M.; McGreevy, J.; Senthil, T. [Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2011-05-15T23:59:59.000Z

    Topological insulators are characterized by the presence of gapless surface modes protected by time-reversal symmetry. In three space dimensions the magnetoelectric response is described in terms of a bulk {theta} term for the electromagnetic field. Here we construct theoretical examples of such phases that cannot be smoothly connected to any band insulator. Such correlated topological insulators admit the possibility of fractional magnetoelectric response described by fractional {theta}/{pi}. We show that fractional {theta}/{pi} is only possible in a gapped time-reversal-invariant system of bosons or fermions if the system also has deconfined fractional excitations and associated degenerate ground states on topologically nontrivial spaces. We illustrate this result with a concrete example of a time-reversal-symmetric topological insulator of correlated bosons with {theta}=({pi}/4). Extensions to electronic fractional topological insulators are briefly described.

  17. Correlated Topological Insulators and the Fractional Magnetoelectric Effect

    E-Print Network [OSTI]

    Brian Swingle; Maissam Barkeshli; John McGreevy; T. Senthil

    2010-05-06T23:59:59.000Z

    Topological insulators are characterized by the presence of gapless surface modes protected by time-reversal symmetry. In three space dimensions the magnetoelectric response is described in terms of a bulk theta term for the electromagnetic field. Here we construct theoretical examples of such phases that cannot be smoothly connected to any band insulator. Such correlated topological insulators admit the possibility of fractional magnetoelectric response described by fractional theta/pi. We show that fractional theta/pi is only possible in a gapped time reversal invariant system of bosons or fermions if the system also has deconfined fractional excitations and associated degenerate ground states on topologically non-trivial spaces. We illustrate this result with a concrete example of a time reversal symmetric topological insulator of correlated bosons with theta = pi/4. Extensions to electronic fractional topological insulators are briefly described.

  18. Design of Experiments Results for the Feedthru Insulator

    SciTech Connect (OSTI)

    BENAVIDES,GILBERT L.; VAN ORNUM,DAVID J.; BACA,MAUREEN R.; APPEL,PATRICIA E.

    1999-12-01T23:59:59.000Z

    A design of experiments (DoE) was performed at Ceramtec to improve the yield of a cermet part known as the feedthru insulator. The factors chosen to be varied in this DoE were syringe orifice size, fill condition, solvent, and surfactant. These factors were chosen because of their anticipated effect on the cermet slurry and its consequences to the feedthru insulator in succeeding fabrication operations. Response variables to the DoE were chosen to be indirect indicators of production yield for the feedthru insulator. The solvent amount used to mix the cermet slurry had the greatest overall effect on the response variables. Based upon this DoE, there is the potential to improve the yield not only for the feedthru insulator but for other cermet parts as well. This report thoroughly documents the DoE and contains additional information regarding the feedthru insulator.

  19. Testing of Compact Bolted Fasteners with Insulation and Friction-Enhanced Shims for NCSX

    SciTech Connect (OSTI)

    L. E. Dudek, J.H. Chrzanowski, G. Gettelfinger, P. Heitzenroeder, S. Jurczynski, M. Viola and K. Freudenberg

    2009-02-04T23:59:59.000Z

    The fastening of the National Compact Stellarator Experiment's (NCSX) modular coils presented a number of engineering and manufacturing challenges due to the high magnetic forces, need to control induced currents, tight tolerances and restrictive space envelope. A fastening method using high strength studs, jack nuts, insulating spacers, bushings and alumina coated shims was developed which met the requirements. A test program was conducted to verify the design. The tests included measurements of flatness of the spacers, determination of contact area, torque vs. tension of the studs and jack nuts, friction coefficient tests on the alumina and G-10 insulators, electrical tests, and tension relaxation tests due to temperature excursions from room temperature to liquid nitrogen temperatures. This paper will describe the design and the results of the test program.

  20. Development of a Process to Build Polyimide Insulated Magnets For Operation at 350C

    SciTech Connect (OSTI)

    Zatz, Irving J.

    2013-07-09T23:59:59.000Z

    An extensive R&D program has been conducted that has confirmed the feasibility of designing and fabricating copper alloy magnets that can successfully operate at temperatures as high as 350C. The process, originally developed for the possibility of manufacturing in-vessel resonant magnetic field perturbation (RMP) coils for JET, has been optimized for insulated magnet (and, potentially, other high temperature component) applications. One of the benefits of high temperature operation is that active cooling may no longer be required, greatly simplifying magnet/component design. These elevated temperatures are beyond the safe operating limits of conventional OFHC copper and the epoxies that bond and insulate the turns of typical magnets. This would necessitate the use an alternative copper alloy conductor such as C18150 (CuCrZr). Coil manufacture with polyimide is very similar to conventional epoxy bonded coils. Conductors would be dry wound then impregnated with polyimide of low enough viscosity to permit saturation, then cured; similar to the vacuum pressure impregnation process used for conventional epoxy bonded coils. Representative polyimide insulated coils were mechanically tested at both room temperature and 350C. Mechanical tests included turn-to-turn shear bond strength and overall polyimide adhesion strength, as well as the flexural strength of a 48-turn polyimide-bonded coil bundle. This paper will detail the results of the testing program on coil samples. These results demonstrate mechanical properties as good, or better than epoxy bonded magnets, even at 350C.

  1. Scattering theory of topological insulators and superconductors

    E-Print Network [OSTI]

    I. C. Fulga; F. Hassler; A. R. Akhmerov

    2013-01-10T23:59:59.000Z

    The topological invariant of a topological insulator (or superconductor) is given by the number of symmetry-protected edge states present at the Fermi level. Despite this fact, established expressions for the topological invariant require knowledge of all states below the Fermi energy. Here, we propose a way to calculate the topological invariant employing solely its scattering matrix at the Fermi level without knowledge of the full spectrum. Since the approach based on scattering matrices requires much less information than the Hamiltonian-based approaches (surface versus bulk), it is numerically more efficient. In particular, is better-suited for studying disordered systems. Moreover, it directly connects the topological invariant to transport properties potentially providing a new way to probe topological phases.

  2. Electromagnetic Scattering by Spheres of Topological Insulators

    E-Print Network [OSTI]

    Ge, Lixin; Zi, Jian

    2015-01-01T23:59:59.000Z

    The electromagnetic scattering properties of topological insulator (TI) spheres are systematically studied in this paper. Unconventional backward scattering caused by the topological magneto-electric (TME) effect of TIs are found in both Rayleigh and Mie scattering regimes. This enhanced backward scattering can be achieved by introducing an impedance-matched background which can suppress the bulk scattering. For the cross-polarized scattering coefficients, interesting antiresonances are found in the Mie scattering regime, wherein the cross-polarized electromagnetic fields induced by the TME effect are trapped inside TI spheres. In the Rayleigh limit, the quantized TME effect of TIs can be determined by measuring the electric-field components of scattered waves in the far field.

  3. Photonic spin Hall effect in topological insulators

    E-Print Network [OSTI]

    Zhou, Xinxing; Ling, Xiaohui; Chen, Shizhen; Luo, Hailu; Wen, Shuangchun

    2013-01-01T23:59:59.000Z

    In this paper we theoretically investigate the photonic spin Hall effect (SHE) of a Gaussian beam reflected from the interface between air and topological insulators (TIs). The photonic SHE is attributed to spin-orbit coupling and manifests itself as in-plane and transverse spin-dependent splitting. We reveal that the spin-orbit coupling effect in TIs can be routed by adjusting the axion angle variations. Unlike the transverse spin-dependent splitting, we find that the in-plane one is sensitive to the axion angle. It is shown that the polarization structure in magneto-optical Kerr effect is significantly altered due to the spin-dependent splitting in photonic SHE. We theoretically propose a weak measurement method to determine the strength of axion coupling by probing the in-plane splitting of photonic SHE.

  4. Topological Insulators Avoid the Parity Anomaly

    E-Print Network [OSTI]

    Michael Mulligan; F. J. Burnell

    2013-01-17T23:59:59.000Z

    The surface of a 3+1d topological insulator hosts an odd number of gapless Dirac fermions when charge conjugation and time-reversal symmetries are preserved. Viewed as a purely 2+1d system, this surface theory would necessarily explicitly break parity and time-reversal when coupled to a fluctuating gauge field. Here we explain why such a state can exist on the boundary of a 3+1d system without breaking these symmetries, even if the number of boundary components is odd. This is accomplished from two complementary perspectives: topological quantization conditions and regularization. We first discuss the conditions under which (continuous) large gauge transformations may exist when the theory lives on a boundary of a higher-dimensional spacetime. Next, we show how the higher-dimensional bulk theory is essential in providing a parity-invariant regularization of the theory living on the lower-dimensional boundary or defect.

  5. Highly Insulating Residential Windows Using Smart Automated Shading...

    Office of Environmental Management (EM)

    The windows will function autonomously and in a networked configuration. Project Impact LBNL is aiming toward a mature market cost increment of 12ft2 of window. LBNL will also...

  6. Highly Insulating Residential Windows Using Smart Automated Shading |

    Energy Savers [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 Office of Inspector General Office0-72.pdfGeorge Waldmann GeorgeLogging|America Top Innovation |R Walls -of

  7. High-Voltage Insulators and Components - Energy Innovation Portal

    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),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun withconfinement plasmas in theinPlastics - Energy

  8. Highly Insulating Residential Windows Using Smart Automated Shading |

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

    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 Delicious Rank EERE:Year in3.pdfEnergy Health and Productivity QuestionnaireSingle EmitterOffersDepartment

  9. Highly insulating Residential Windows Using Smart Automated Shading

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

    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 Delicious Rank EERE:YearRound-UpHeatMulti-Dimensional Subject:Ground HawaiiWaste Heat Recovery:|Department ofChristian

  10. Characterization of the pentacene thin-film transistors with an epoxy resin-based polymeric gate insulator

    E-Print Network [OSTI]

    Boyer, Edmond

    Characterization of the pentacene thin-film transistors with an epoxy resin-based polymeric gate seeking desirable semi- conductor/insulator combinations [3]. In this study, we adopted an epoxy resin fabricated and characterized. SU-8, a reliable epoxy-based pho- toresist, is tested as a potential highly

  11. Noncontact deep level photo-thermal spectroscopy: Technique and application to semi-insulating GaAs Wafers

    E-Print Network [OSTI]

    Mandelis, Andreas

    to high resistivity materials, since the Debye-Huckel length is too large several milli- meters for semi materials. In DLPTS, the thermal recovery of carriers after excita- tion is monitored by a subNoncontact deep level photo-thermal spectroscopy: Technique and application to semi-insulating Ga

  12. Holographic classification of Topological Insulators and its 8-fold periodicity

    E-Print Network [OSTI]

    André LeClair; Denis Bernard

    2012-05-16T23:59:59.000Z

    Using generic properties of Clifford algebras in any spatial dimension, we explicitly classify Dirac hamiltonians with zero modes protected by the discrete symmetries of time-reversal, particle-hole symmetry, and chirality. Assuming the boundary states of topological insulators are Dirac fermions, we thereby holographically reproduce the Periodic Table of topological insulators found by Kitaev and Ryu. et. al, without using topological invariants nor K-theory. In addition we find candidate Z_2 topological insulators in classes AI, AII in dimensions 0,4 mod 8 and in classes C, D in dimensions 2,6 mod 8.

  13. Torsional Response and Dissipationless Viscosity in Topological Insulators

    E-Print Network [OSTI]

    Taylor L. Hughes; Robert G. Leigh; Eduardo Fradkin

    2011-01-18T23:59:59.000Z

    We consider the visco-elastic response of the electronic degrees of freedom in 2D and 3D topological insulators (TI). Our primary focus is on the 2D Chern insulator which exhibits a bulk dissipationless viscosity analogous to the quantum Hall viscosity predicted in integer and fractional quantum Hall states. We show that the dissipationless viscosity is the response of a TI to torsional deformations of the underlying lattice geometry. The visco-elastic response also indicates that crystal dislocations in Chern insulators will carry momentum density. We briefly discuss generalizations to 3D which imply that time-reversal invariant TI's will exhibit a quantum Hall viscosity on their surfaces.

  14. Outdoor polymeric insulators long-term exposed to HVDC

    SciTech Connect (OSTI)

    Soerqvist, T.; Vlastos, A.E. [Chalmers Univ. of Technology, Gothenburg (Sweden)] [Chalmers Univ. of Technology, Gothenburg (Sweden)

    1997-04-01T23:59:59.000Z

    Field experience from outdoor polymeric insulators exposed to HVDC under natural contamination conditions is presented. This paper summarizes the peak leakage current statistics, the hydrophobicity and the surface material conditions studied by electron spectroscopy for chemical analysis (ESCA) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. The results show a strong interrelation between the surface conditions and the performance with respect to leakage currents. Moreover, the results show that the surface conditions and the performance of the insulators exposed to HVDC are rather similar to those of the insulators exposed to HVAC.

  15. Experimental Realization of a Three-Dimensional Topological Insulator, Bi 2Te3

    SciTech Connect (OSTI)

    Siemons, W.

    2010-02-24T23:59:59.000Z

    Three-dimensional topological insulators are a new state of quantum matter with a bulk gap and odd number of relativistic Dirac fermions on the surface. By investigating the surface state of Bi{sub 2}Te{sub 3} with angle-resolved photoemission spectroscopy, we demonstrate that the surface state consists of a single nondegenerate Dirac cone. Furthermore, with appropriate hole doping, the Fermi level can be tuned to intersect only the surface states, indicating a full energy gap for the bulk states. Our results establish that Bi{sub 2}Te{sub 3} is a simple model system for the three-dimensional topological insulator with a single Dirac cone on the surface. The large bulk gap of Bi{sub 2}Te{sub 3} also points to promising potential for high-temperature spintronics applications.

  16. Pipeline system insulation: thermal insulation and corrosion prevention. December 1985-February 1988 (citations from the rubber and plastics research association data base). Report for December 1985-February 1988

    SciTech Connect (OSTI)

    Not Available

    1988-03-01T23:59:59.000Z

    This bibliography contains citations concerning thermal and corrosion insulating of pipeline systems used to transfer liquids and gases. Thermal aging of polyurethane foam for insulating heating pipes, extrusion-film pipeline-insulation materials and processes, flexible expanded nitrile-rubber pipeline insulation with class 1 fire rating, and underground fiberglass-reinforced polyester insulated-pipeline systems are among the topics discussed. Applications in solar-heating systems, underground water, oil, and gas, interior hot water and cold water lines under seawater, and chemical-plant pipeline-system insulation are included. (This updated bibliography contains 139 citations, all of which are new entries to the previous edition.)

  17. Science Highlight August 2010 New State of Topological Insulators Offers New Opportunities

    E-Print Network [OSTI]

    Wechsler, Risa H.

    Science Highlight ­ August 2010 New State of Topological Insulators Offers New Opportunities Three dimensional topological insulators are a new state of quantum matter with a bulk gap and odd number insulator enters the insulating masive Dirac fermion state, a state that harbors striking topological

  18. Topological Insulators with Ultracold Atoms Indubala I. Satija and Erhai Zhao

    E-Print Network [OSTI]

    Satija, Indu

    Chapter 12 Topological Insulators with Ultracold Atoms Indubala I. Satija and Erhai Zhao Abstract- tance is topological insulators, materials that are insulating in the interior but con- duct along of matter known as Topological Insulators. I.I. Satija (B) · E. Zhao School of Physics, Astronomy

  19. Fermi-level tuning of topological insulator thin films Masaki Aitani,1

    E-Print Network [OSTI]

    Hasegawa, Shuji

    Fermi-level tuning of topological insulator thin films Masaki Aitani,1 Yusuke Sakamoto,1 Toru Topological insulators are insulating materials but have metallic edge states with peculiar prop- erties properties of topological insulator ultrathin Bi2Te3 films by angle-resolved photoemission spectroscopy

  20. PHYSICAL REVIEW B 85, 115415 (2012) Smooth gauge for topological insulators

    E-Print Network [OSTI]

    Vanderbilt, David

    2012-01-01T23:59:59.000Z

    PHYSICAL REVIEW B 85, 115415 (2012) Smooth gauge for topological insulators Alexey A. Soluyanov polarization3,4 and the anomalous Hall conductance.5,6 The recent discovery of topological insulators7,8 has-like functions for 2D Z2 insulators (i.e., quantum spin- Hall insulators) that are smooth functions of k

  1. Topological Insulators with Ultracold Atoms Indubala I Satija and Erhai Zhao

    E-Print Network [OSTI]

    Satija, Indu

    Topological Insulators with Ultracold Atoms Indubala I Satija and Erhai Zhao School of Physics is topological insulators, materials that are insulating in the interior but conduct along the edges. Quantum to the family of exotic states of matter known as Topological Insulators. QH and QSH effect usually requires

  2. Sound-insulation layers low-frequency modeling, using the fuzzy structure theory

    E-Print Network [OSTI]

    Boyer, Edmond

    09NVC-0163 Sound-insulation layers low-frequency modeling, using the fuzzy structure theory Laurent [20,200] Hz, sound-insulation layer modeling remains a critical topic. Recent work allows- insulation layer. Nevertheless, such an approach requires a FE model of sound-insulation layer, which may

  3. Key-Insulated Signcryption (Science and Technology on Communication Security Laboratory,

    E-Print Network [OSTI]

    Zheng, Yuliang

    Key-Insulated Signcryption Jia Fan 1 (Science and Technology on Communication Security Laboratory addresses the issue of key exposure by proposing a key-insulated signcryption technique. We define a security model for key-insulated signcryption and prove that the key- insulated signcryption technique

  4. Exchange-Coupling-Induced Symmetry Breaking in Topological Insulators

    E-Print Network [OSTI]

    Wei, Peng

    An exchange gap in the Dirac surface states of a topological insulator (TI) is necessary for observing the predicted unique features such as the topological magnetoelectric effect as well as to confine Majorana fermions. ...

  5. Correlated topological insulators and the fractional magnetoelectric effect

    E-Print Network [OSTI]

    Swingle, Brian Gordon

    Topological insulators are characterized by the presence of gapless surface modes protected by time-reversal symmetry. In three space dimensions the magnetoelectric response is described in terms of a bulk ? [theta] term ...

  6. Topological crystalline insulators and Dirac octets in antiperovskites

    E-Print Network [OSTI]

    Liu, Junwei

    We predict a class of topological crystalline insulators in the antiperovskite material family with the chemical formula A[subscript 3]BX. Here the nontrivial topology arises from band inversion between two J = 3/2 quartets, ...

  7. Classification of Interacting Electronic Topological Insulators in Three Dimensions

    E-Print Network [OSTI]

    Wang, Chong

    A fundamental open problem in condensed-matter physics is how the dichotomy between conventional and topological band insulators is modified in the presence of strong electron interactions. We show that there are six ...

  8. Driven electronic states at the surface of a topological insulator

    E-Print Network [OSTI]

    Fregoso, Benjamin M.

    Motivated by recent photoemission experiments on the surface of topological insulators we compute the spectrum of driven topological surface excitations in the presence of an external light source. We completely characterize ...

  9. Interacting fermionic topological insulators/superconductors in three dimensions

    E-Print Network [OSTI]

    Wang, Chong

    Symmetry protected topological (SPT) phases are a minimal generalization of the concept of topological insulators to interacting systems. In this paper, we describe the classification and properties of such phases for ...

  10. Topological Crystalline Insulators in the SnTe Material Class

    E-Print Network [OSTI]

    Hsieh, Timothy Hwa-wei

    Topological crystalline insulators are new states of matter in which the topological nature of electronic structures arises from crystal symmetries. Here we predict the first material realization of topological crystalline ...

  11. Homotopy Theory of Strong and Weak Topological Insulators

    E-Print Network [OSTI]

    Ricardo Kennedy; Charles Guggenheim

    2014-09-08T23:59:59.000Z

    We use homotopy theory to extend the notion of strong and weak topological insulators to the non-stable regime (low numbers of occupied/empty energy bands). We show that for strong topological insulators in d spatial dimensions to be "truly d-dimensional", i.e. not realizable by stacking lower-dimensional insulators, a more restrictive definition of "strong" is required. However, this does not exclude weak topological insulators from being "truly d-dimensional", which we demonstrate by an example. Additionally, we prove some useful technical results, including the homotopy theoretic derivation of the factorization of invariants over the torus into invariants over spheres in the stable regime, as well as the rigorous justification of replacing $T^d$ by $S^d$ and $T^{d_k}\\times S^{d_x}$ by $S^{d_k+d_x}$ as is common in the current literature.

  12. Microscopic Realization of Two-Dimensional Bosonic Topological Insulators

    E-Print Network [OSTI]

    Liu, Zheng-Xin

    It is well known that a bosonic Mott insulator can be realized by condensing vortices of a boson condensate. Usually, a vortex becomes an antivortex (and vice versa) under time reversal symmetry, and the condensation of ...

  13. Topological Spin Texture in a Quantum Anomalous Hall Insulator

    E-Print Network [OSTI]

    Wu, Jiansheng

    The quantum anomalous Hall (QAH) effect has been recently discovered in an experiment using a thin-film topological insulator with ferromagnetic ordering and strong spin-orbit coupling. Here we investigate the spin degree ...

  14. Measure Guideline: Sealing and Insulating of Ducts in Existing Homes

    SciTech Connect (OSTI)

    Aldrich, R.; Puttagunta, S.

    2011-12-01T23:59:59.000Z

    This document begins with a discussion on potential cost and performance benefits of duct sealing and insulating. It continues with a review of typical duct materials and components and the overall procedures for assessing and improving the duct system.

  15. Design of a variable-conductance vacuum insulation

    SciTech Connect (OSTI)

    Benson, D K; Potter, T F; Tracy, C E

    1994-01-01T23:59:59.000Z

    This paper describes one approach to the design of a variable-conductance vacuum insulation. In this design, the vacuum insulation consists of a permanently sealed, thin sheet steel, evacuated envelope of whatever geometry is required for the application. The steel envelope is supported internally against the atmospheric pressure loads by an array of discrete, low-conductance, ceramic supports, and radiative heat transfer is blocked by layers of thin metal radiation shields. Thermal conductance through this insulation is controlled electronically by changing the temperature of a small metal hydride connected to the vacuum envelope. The hydride reversibly absorbs/desorbs hydrogen to produce a hydrogen pressure typically within the range from less than 10{sup {minus}6} to as much as 1 torr. Design calculations are compared with results from laboratory tests of bench scale samples, and some possible automotive applications for this variable-conductance vacuum insulation are suggested.

  16. Aerogel-Based Insulation for Industrial Steam Distribution Systems

    SciTech Connect (OSTI)

    John Williams

    2011-03-30T23:59:59.000Z

    Thermal losses in industrial steam distribution systems account for 977 trillion Btu/year in the US, more than 1% of total domestic energy consumption. Aspen Aerogels worked with Department of Energy’s Industrial Technologies Program to specify, develop, scale-up, demonstrate, and deliver Pyrogel XT®, an aerogel-based pipe insulation, to market to reduce energy losses in industrial steam systems. The product developed has become Aspen’s best selling flexible aerogel blanket insulation and has led to over 60 new jobs. Additionally, this product has delivered more than ~0.7 TBTU of domestic energy savings to date, and could produce annual energy savings of 149 TBTU by 2030. Pyrogel XT’s commercial success has been driven by it’s 2-4X better thermal performance, improved durability, greater resistance to corrosion under insulation (CUI), and faster installation times than incumbent insulation materials.

  17. Aerogel Insulation: The Materials Science of Empty Space

    Broader source: Energy.gov [DOE]

    Empty space can be good, like a blank canvas for an artist, or it can be bad, like an attic without insulation for a homeowner.  But when a technological breakthrough provides just the right amount...

  18. Energy and Emissions Savings through Insulation Upgrade Projects

    E-Print Network [OSTI]

    Lettich, M.

    2008-01-01T23:59:59.000Z

    The presentation demonstrates the value of including insulation system assessment, repairs and upgrades on a facility's physical function and its importance in the overall energy and environmental management program. Financial and environmental...

  19. Manipulation of bacteria using three dimensional insulator based dielectrophoresis

    E-Print Network [OSTI]

    Braff, William Allan

    2011-01-01T23:59:59.000Z

    Insulator-based dielectrophoresis (iDEP) is a very promising technique for sorting microparticles based on their electrical properties. By using constrictions in a microchannel to generate large electric field gradients, ...

  20. A Comprehensive Map of Insulator Elements for the Drosophila Genome

    E-Print Network [OSTI]

    White, Kevin P.

    Insulators are DNA sequences that control the interactions among genomic regulatory elements and act as chromatin boundaries. A thorough understanding of their location and function is necessary to address the complexities ...

  1. Temperature dependence of ambipolar diffusion in silicon-on-insulator

    E-Print Network [OSTI]

    Zhao, Hui

    2008-03-01T23:59:59.000Z

    Spatiotemporal dynamics of electron-hole pairs locally excited in a silicon-on-insulator structure by indirect interband absorption are studied by measuring differential transmission caused by free-carrier absorption of a ...

  2. Linear particle accelerator with seal structure between electrodes and insulators

    DOE Patents [OSTI]

    Broadhurst, John H. (Golden Valley, MN)

    1989-01-01T23:59:59.000Z

    An electrostatic linear accelerator includes an electrode stack comprised of primary electrodes formed or Kovar and supported by annular glass insulators having the same thermal expansion rate as the electrodes. Each glass insulator is provided with a pair of fused-in Kovar ring inserts which are bonded to the electrodes. Each electrode is designed to define a concavo-convex particle trap so that secondary charged particles generated within the accelerated beam area cannot reach the inner surface of an insulator. Each insulator has a generated inner surface profile which is so configured that the electrical field at this surface contains no significant tangential component. A spark gap trigger assembly is provided, which energizes spark gaps protecting the electrodes affected by over voltage to prevent excessive energy dissipation in the electrode stack.

  3. Kingspan Insulated Panels: Proposed Penalty (2013-CE-5353)

    Broader source: Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that Kingspan Insulated Panels, Inc. failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards.

  4. Thermal Effects of Moisture in Rigid Insulation Board

    E-Print Network [OSTI]

    Crow, G. W.

    The impact of moisture in rigid roof insulation upon energy consumption is often assumed to be a simple function of the conductance. This paper will show that there are complex interactions between conductance, thermal mass, and climate. The energy...

  5. aluminum nitride insulator: Topics by E-print Network

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

    K-r grown by a modified Bridgman tech- nique,r6 Rollins, Andrew M. 27 Low-voltage organic thin film transistors with hydrophobic aluminum nitride film as gate insulator Materials...

  6. An Investigation of Insulator Proteins in Mosquito Genomes

    E-Print Network [OSTI]

    Johanson, Michael

    2013-08-02T23:59:59.000Z

    of transgenes in mosquito species. The use of insulator sequences to flank transgenes may have the ability to overcome position effects caused by the genomic environment surrounding the insertion site. CTCF is a multifunctional protein, conserved from humans...

  7. Performance of MHD insulating materials in a potassium environment

    SciTech Connect (OSTI)

    Natesan, K.; Park, J.H.; Rink, D.L. (Argonne National Lab., IL (United States)); Thomas, C.A. (USDOE Pittsburgh Energy Technology Center, PA (United States))

    1991-12-01T23:59:59.000Z

    The objectives of this study are to evaluate the compatibility of the MHD insulating materials boron nitride and silicon nitride in a potassium environment at temperatures of 1000 and 1400{degrees}F (538 and 760{degrees}C, respectively) and to measure the electrical conductivities of the specimens before and after exposure to potassium. Based on the test results, an assessment is to be made of the suitability of these materials for application as insulator materials in an MHD channel.

  8. Topological insulators/superconductors: Potential future electronic materials

    SciTech Connect (OSTI)

    Hor, Y. S. [Department of Physics, Missouri University of Science and Technology, Rolla, MO 65409 (United States)

    2014-03-05T23:59:59.000Z

    A new material called topological insulator has been discovered and becomes one of the fastest growing field in condensed matter physics. Topological insulator is a new quantum phase of matter which has Dirac-like conductivity on its surface, but bulk insulator through its interior. It is considered a challenging problem for the surface transport measurements because of dominant internal conductance due to imperfections of the existing crystals of topological insulators. By a proper method, the internal bulk conduction can be suppressed in a topological insulator, and permit the detection of the surface currents which is necessary for future fault-tolerant quantum computing applications. Doped topological insulators have depicted a large variety of bulk physical properties ranging from magnetic to superconducting behaviors. By chemical doping, a TI can change into a bulk superconductor. Nb{sub x}Bi{sub 2}Se{sub 3} is shown to be a superconductor with T{sub c} ? 3.2 K, which could be a potential candidate for a topological superconductor.

  9. External Insulation of Masonry Walls and Wood Framed Walls

    SciTech Connect (OSTI)

    Baker, P.

    2013-01-01T23:59:59.000Z

    The use of exterior insulation on a building is an accepted and effective means to increase the overall thermal resistance of the assembly that also has other advantages of improved water management and often increased air tightness of building assemblies. For thin layers of insulation (1" to 1 1/2"), the cladding can typically be attached directly through the insulation back to the structure. For thicker insulation layers, furring strips have been added as a cladding attachment location. This approach has been used in the past on numerous Building America test homes and communities (both new and retrofit applications), and has been proven to be an effective and durable means to provide cladding attachment. However, the lack of engineering data has been a problem for many designers, contractors, and code officials. This research project developed baseline engineering analysis to support the installation of thick layers of exterior insulation on existing masonry and frame walls. Furthermore, water management details necessary to integrate windows, doors, decks, balconies and roofs were created to provide guidance on the integration of exterior insulation strategies with other enclosure elements.

  10. Topology of crystalline insulators and superconductors

    E-Print Network [OSTI]

    Ken Shiozaki; Masatoshi Sato

    2014-10-14T23:59:59.000Z

    We complete a classification of topological phases and their topological defects in crystalline insulators and superconductors. We consider topological phases and defects described by non-interacting Bloch and Bogoliubov de Gennes Hamiltonians that support additional order-two spatial symmetry, besides any of ten classes of symmetries defined by time-reversal symmetry and particle-hole symmetry. The additional order-two spatial symmetry we consider is general and it includes $Z_2$ global symmetry, mirror reflection, two-fold rotation, inversion, and their magnetic point group symmetries. We find that the topological periodic table shows a novel periodicity in the number of flipped coordinates under the order-two spatial symmetry, in addition to the Bott-periodicity in the space dimensions. Various symmetry protected topological phases and gapless modes will be identified and discussed in a unified framework. We also present topological classification of symmetry protected Fermi points. The bulk classification and the surface Fermi point classification provide a novel realization of the bulk-boundary correspondence in terms of the K-theory.

  11. Advanced insulated gate bipolar transistor gate drive

    DOE Patents [OSTI]

    Short, James Evans (Monongahela, PA); West, Shawn Michael (West Mifflin, PA); Fabean, Robert J. (Donora, PA)

    2009-08-04T23:59:59.000Z

    A gate drive for an insulated gate bipolar transistor (IGBT) includes a control and protection module coupled to a collector terminal of the IGBT, an optical communications module coupled to the control and protection module, a power supply module coupled to the control and protection module and an output power stage module with inputs coupled to the power supply module and the control and protection module, and outputs coupled to a gate terminal and an emitter terminal of the IGBT. The optical communications module is configured to send control signals to the control and protection module. The power supply module is configured to distribute inputted power to the control and protection module. The control and protection module outputs on/off, soft turn-off and/or soft turn-on signals to the output power stage module, which, in turn, supplies a current based on the signal(s) from the control and protection module for charging or discharging an input capacitance of the IGBT.

  12. CERTIFICATE OF FIELD VERIFICATION AND DIAGNOSTIC TESTING CF-4R-ENV-22 Quality Insulation Installation (QII) -Insulation Stage Checklist (Page 1 of 3)

    E-Print Network [OSTI]

    CERTIFICATE OF FIELD VERIFICATION AND DIAGNOSTIC TESTING CF-4R-ENV-22 Quality Insulation Installation (QII) - Insulation Stage Checklist (Page 1 of 3) Site Address: Enforcement Agency: Permit Number: ____________ 2008 Residential Compliance Forms May 2012 All structural framing areas shall be insulated in a manner

  13. Large anomalous Hall effect in ferromagnetic insulator-topological insulator heterostructures

    SciTech Connect (OSTI)

    Alegria, L. D.; Petta, J. R. [Department of Physics, Princeton University, Princeton, New Jersey 08544 (United States); Ji, H.; Cava, R. J. [Department of Chemistry, Princeton University, Princeton, New Jersey 08544 (United States); Yao, N. [Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, New Jersey 08544 (United States); Clarke, J. J. [Hitachi High Technologies America, Inc., Clarksburg, Maryland 20871 (United States)

    2014-08-04T23:59:59.000Z

    We demonstrate the van der Waals epitaxy of the topological insulator compound Bi{sub 2}Te{sub 3} on the ferromagnetic insulator Cr{sub 2}Ge{sub 2}Te{sub 6}. The layers are oriented with (001)Bi{sub 2}Te{sub 3}||(001)Cr{sub 2}Ge{sub 2}Te{sub 6} and (110)Bi{sub 2}Te{sub 3}||(100)Cr{sub 2}Ge{sub 2}Te{sub 6}. Cross-sectional transmission electron microscopy indicates the formation of a sharp interface. At low temperatures, bilayers consisting of Bi{sub 2}Te{sub 3} on Cr{sub 2}Ge{sub 2}Te{sub 6} exhibit a large anomalous Hall effect (AHE). Tilted field studies of the AHE indicate that the easy axis lies along the c-axis of the heterostructure, consistent with magnetization measurements in bulk Cr{sub 2}Ge{sub 2}Te{sub 6}. The 61?K Curie temperature of Cr{sub 2}Ge{sub 2}Te{sub 6} and the use of near-stoichiometric materials may lead to the development of spintronic devices based on the AHE.

  14. Scientists Connect Thermoelectric Materials and Topological Insulators...

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

    and relativity in combination produce a unique conducting state on the surface. Excellent thermoelectric performance depends on a material having both high conductivity and high...

  15. Thermal insulation standards for residential building envelopes in Iran

    SciTech Connect (OSTI)

    Eslami, H.M.

    1987-01-01T23:59:59.000Z

    This project develops thermal-insulation standards for residential-building envelopes in Iran which would later serve as the groundwork for development of thermal-insulation regulations in the country. The energy performance of the opaque components of present common construction systems was studied. The results clearly indicate the need for improvement of the energy performance of building components through the application of thermal insulation. The initial cost of insulating the building varied from 2.0-3.5% of the total construction cost, depending on the climate location, form and size of the building. Discounted pay-back period ranged from two to four years. Component performance standards were developed with prescriptive recommendations to meet with the level of technical skills of the parties involved in the implementation and control of standards. The macro-economic assessment of insulation standards proves annual savings of billions of Rials on the national level and also the creation of more jobs in construction-related industries.

  16. Supporting documentation for the 1997 revision to the DOE Insulation Fact Sheet

    SciTech Connect (OSTI)

    Stovall, T.K.

    1997-08-22T23:59:59.000Z

    The Department of Energy (DOE) Insulation Fact Sheet has been revised to reflect developments in energy conservation technology and the insulation market. A nationwide insulation cost survey was made by polling insulation contractors and builders, and the results are reported here. These costs, along with regional weather data, regional fuel costs, and fuel-specific system efficiencies were used to produce recommended insulation levels for new and existing houses. This report contains all of the methodology, algorithms, assumptions, references, and data resources that were used to produce the 1997 DOE Insulation Fact Sheet.

  17. The fabrication of a vanadium-stainless steel test section for MHD testing of insulator coatings in flowing lithium

    SciTech Connect (OSTI)

    Reed, C.B.; Mattas, R.F.; Smith, D.L.; Chung, H.; Tsai, H.-C. [Argonne National Lab., IL (United States); Morgan, G.D.; Wille, G.W. [McDonnell Douglas Aerospace, St. Louis, MO (United States). High Energy Systems; Johnson, W.R. [General Atomics, San Diego, CA (United States); Young, C. [Century Tubes, Inc., San Diego, CA (United States)

    1996-12-31T23:59:59.000Z

    To test the magnetohydrodynamic (MHD) pressure drop reduction performance of candidate insulator coatings for the ITER Vanadium/Lithium Breeding Blanket, a test section comprised of a V- 4Cr-4Ti liner inside a stainless steel pipe was designed and fabricated. Theoretically, the MHD pressure drop reduction benefit resulting, from an electrically insulating coating on a vanadium- lined pipe is identical to the benefit derived from an insulated pipe fabricated of vanadium alone. A duplex test section design consisting of a V alloy liner encased in a SS pressure boundary provided protection for vanadium from atmospheric contamination during operation at high temperature and obviated any potential problems with vanadium welding while also minimizing the amount of V alloy material required. From the MHD and insulator coating- point of view, the test section outer SS wall and inner V alloy liner can be modeled simply as a wall having a sandwich construction. Two 52.3 mm OD x 2.9 m long V-alloy tubes were fabricated by Century Tubes from 64 mm x 200 mm x 1245 mm extrusions produced by Teledyne Wah Chang. The test section`s duplex structure was subsequently fabricated at Century Tubes by drawing down a SS pipe (2 inch schedule 10) over one of the 53.2 mm diameter V tubes.

  18. Chiral Topological Insulator on Nambu 3-Algebraic Geometry

    E-Print Network [OSTI]

    Kazuki Hasebe

    2014-08-02T23:59:59.000Z

    Chiral topological insulator (AIII-class) with Landau levels is constructed based on the Nambu 3-algebraic geometry. We clarify the geometric origin of the chiral symmetry of the AIII-class topological insulator in the context of non-commutative geometry of 4D quantum Hall effect. The many-body groundstate wavefunction is explicitly derived as a $(l,l,l-1)$ Laughlin-Halperin type wavefunction with unique $K$-matrix structure. Fundamental excitation is identified with anyonic string-like object with fractional charge ${1}/({1+2(l-1)^2})$. The Hall effect of the chiral topological insulators turns out be a color version of Hall effect, which exhibits a dual property of the Hall and spin-Hall effects.

  19. Plasmon-phonon interactions in topological insulator rings

    E-Print Network [OSTI]

    Autore, Marta; Di Gaspare, Alessandra; Giliberti, Valeria; Limaj, Odeta; Roy, Pascale; Brahlek, Matthew; Koirala, Nikesh; Oh, Seongshik; de Abajo, Francisco Javier Garcìa; Lupi, Stefano

    2015-01-01T23:59:59.000Z

    The great potential of Dirac electrons for plasmonics and photonics has been readily recognized after their discovery in graphene, followed by applications to smart optical devices. Dirac carriers are also found in topological insulators (TI) --quantum systems having an insulating gap in the bulk and intrinsic Dirac metallic states at the surface--. Here, we investigate the plasmonic response of ring structures patterned in Bi$_2$Se$_3$ TI films, which we investigate through terahertz (THz) spectroscopy. The rings are observed to exhibit a bonding and an antibonding plasmon modes, which we tune in frequency by varying their diameter. We develop an analytical theory based on the THz conductivity of unpatterned films, which accurately describes the strong plasmon-phonon hybridization and Fano interference experimentally observed as the bonding plasmon is swiped across the promineng 2\\,THz phonon exhibited by this material. This work opens the road for the investigation of plasmons in topological insulators and ...

  20. Surface state dominated transport in topological insulator Bi{sub 2}Te{sub 3} nanowires

    SciTech Connect (OSTI)

    Hamdou, Bacel, E-mail: bhamdou@physnet.uni-hamburg.de; Gooth, Johannes; Dorn, August; Nielsch, Kornelius, E-mail: knielsch@physnet.uni-hamburg.de [Institute of Applied Physics, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg (Germany)] [Institute of Applied Physics, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg (Germany); Pippel, Eckhard [Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle (Germany)] [Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle (Germany)

    2013-11-04T23:59:59.000Z

    We report on low temperature magnetoresistance measurements on single-crystalline Bi{sub 2}Te{sub 3} nanowires synthesized via catalytic growth and post-annealing in a Te-rich atmosphere. The observation of Aharonov-Bohm oscillations indicates the presence of topological surface states. Analyses of Subnikov-de Haas oscillations in perpendicular magnetoresistance yield extremely low two-dimensional carrier concentrations and effective electron masses, and very high carrier mobilities. All our findings are in excellent agreement with theoretical predictions of massless Dirac fermions at the surfaces of topological insulators.

  1. Spin connection and boundary states in a topological insulator

    E-Print Network [OSTI]

    V. Parente; P. Lucignano; P. Vitale; A. Tagliacozzo; F. Guinea

    2010-11-02T23:59:59.000Z

    We study the surface resistivity of a three-dimensional topological insulator when the boundaries exhibit a non trivial curvature. We obtain an analytical solution for a spherical topological insulator, and we show that a non trivial quantum spin connection emerges from the three dimensional band structure. We analyze the effect of the spin connection on the scattering by a bump on a flat surface. Quantum effects induced by the geometry lead to resonances when the electron wavelength is comparable to the size of the bump.

  2. Characterization of 3d topological insulators by 2d invariants

    E-Print Network [OSTI]

    Rahul Roy

    2010-04-20T23:59:59.000Z

    The prediction of non-trivial topological phases in Bloch insulators in three dimensions has recently been experimentally verified. Here, I provide a picture for obtaining the $Z_{2}$ invariants for a three dimensional topological insulator by deforming suitable 2d planes in momentum space and by using a formula for the 2d $Z_{2}$ invariant based on the Chern number. The physical interpretation of this formula is also clarified through the connection between this formulation of the $Z_{2}$ invariant and the quantization of spin Hall conductance in two dimensions.

  3. Investigation of single unit flashovers in HVDC insulator strings

    SciTech Connect (OSTI)

    Ishikawa, Kouichi; Kageyama, Hiroshi; Yamada, Yasuhiro [Kansai Electric Power Co., Inc., Osaka (Japan)] [Kansai Electric Power Co., Inc., Osaka (Japan); Matsuoka, Ryosuke; Ito, Susumu; Sakanishi, Kenji [NGK Insulators, Ltd., Nagoya (Japan)] [NGK Insulators, Ltd., Nagoya (Japan)

    1996-10-01T23:59:59.000Z

    In HVDC transmission lines, a special phenomenon, so called single unit flashover, is observed under some special conditions. Only one or two insulator units repeat flashovers, not resulting in an overall flashover along the string. However, higher magnitudes of audible noise, radio and television interferences, may give a serious problem. Based on the investigation on {+-}500-kV full scale insulator strings, higher occurrence probability of single unit flashovers under cold-wet-switch-on conditions was clarified compared with normal continuous operating voltage conditions. Effectiveness of the newly proposed countermeasures to prevent single unit flashovers was demonstrated by experiments in laboratory and in field.

  4. Characterization of Min-K TE-1400 Thermal Insulation

    SciTech Connect (OSTI)

    Hemrick, James Gordon [ORNL; Lara-Curzio, Edgar [ORNL; King, James [ORNL

    2008-07-01T23:59:59.000Z

    Min-K 1400TE insulation material was characterized at Oak Ridge National Laboratory for use in structural applications under gradient temperature conditions. Initial compression testing was performed at room temperature at various loading rates ranging between 5 and 500 psi/hour (?35 and 3500 kPa/hour) to determine the effect of sample size and test specimen geometry on the compressive strength of Min-K. To determine the loading rates that would be used for stress relaxation testing, compression tests were next carried out at various levels followed by stress relaxation under constant strain at temperatures of 650, 850, and 900oC. Additional high temperature compression testing was performed with samples loaded at a rate of 53 psi/hour (365 kPa/hour) in three load steps of 50, 100 and 200 psi (345, 690, and 1380 kPa) with quick unload/load cycles between steps and followed by a hold period in load control (3 to 100 hours) to allow for sample creep. Testing was carried out at 190, 382, 813, and 850oC. Isothermal stress relaxation testing was performed at temperatures of 190, 382, 813, and 850oC and initial loads of 100 and 200 psi (690 and 1380 kPa). Gradient stress relaxation testing was intended to be performed at temperatures of 850/450oC and 450/190oC with initial loads of 100 or 200 psi (690 and 1380 kPa) performed under constant strain utilizing a twelve-step loading scheme with loading every half hour at a rate of 5.56% strain/hour.

  5. Experimental Investigation on Thermal Properties of a Steel-jacketed Steam Heating Pipeline with Vacuum Insulation

    E-Print Network [OSTI]

    Na, W.; Zou, P.

    2006-01-01T23:59:59.000Z

    The steel-jacketed steam heating pipeline employs vacuum insulation to improve the insulating effect and reduce the corrosion, and hence increases the heat transfer efficiency of the heating network and building energy efficiency. It is important...

  6. asbestos pipe-insulation removal: Topics by E-print Network

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

    A&M University - TxSpace Summary: PIPE INSULATION ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram...

  7. Industrial Insulation: An Energy Efficient Technology That Saves Money and Reduces

    E-Print Network [OSTI]

    Brayman, B.

    -but no one knew exactly just how much. Everyone understands that insulation protects people from hot surfaces and that it prevents condensation. Until recently, however no one could quantify the emissions saved for the insulation investment incurred. In fact...

  8. EI2 Insulation Helps Anxious Pooch Find Calm in the Storm | Department...

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

    EI2 Insulation Helps Anxious Pooch Find Calm in the Storm EI2 Insulation Helps Anxious Pooch Find Calm in the Storm Photo of a dog sitting on a bed or couch with a stuffed toy in...

  9. Low-Cost, Haziness-Free, Transparent Insulation Based On a Porous...

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

    Low-Cost, Haziness-Free, Transparent Insulation Based On a Porous Silica Material Low-Cost, Haziness-Free, Transparent Insulation Based On a Porous Silica Material Image of porous...

  10. Graphene-on-Insulator Transistors Made Using C on Ni Chemical-Vapor Deposition

    E-Print Network [OSTI]

    Keast, Craig L.

    Graphene transistors are made by transferring a thin graphene film grown on Ni onto an insulating SiO[subscript 2] substrate. The properties and integration of these graphene-on-insulator transistors are presented and ...

  11. Structurally-driven metal-insulator transition in Ca{sub 2}Ru{sub 1-x}Cr{sub x}O{sub 4} (0{<=}x<0.14): A single crystal X-ray diffraction study

    SciTech Connect (OSTI)

    Qi, T.F., E-mail: tqi2@uky.ed [Center for Advanced Materials, University of Kentucky, Lexington, KY 40506 (United States); Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States); Ge, M. [Center for Advanced Materials, University of Kentucky, Lexington, KY 40506 (United States); High Magnetic Field Laboratory, University of Science and Technology of China, Hefei, Anhui 230026 (China); Korneta, O.B. [Center for Advanced Materials, University of Kentucky, Lexington, KY 40506 (United States); Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States); Parkin, S. [Center for Advanced Materials, University of Kentucky, Lexington, KY 40506 (United States); Department of Chemistry, University of Kentucky, Lexington, KY 40506 (United States); De Long, L.E.; Cao, G. [Center for Advanced Materials, University of Kentucky, Lexington, KY 40506 (United States); Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States)

    2011-04-15T23:59:59.000Z

    Correlation between structure and transport properties are investigated in high-quality single-crystals of Ca{sub 2}Ru{sub 1-x}Cr{sub x}O{sub 4} with 0insulator (MI) transition at 357 K. Upon chromium doping on the ruthenium site, the metal-insulator transition temperature (T{sub MI}) was drastically reduced, and is related to the competition between structural changes that occur upon Cr doping and with decreasing temperature. A strong suppression of structural distortions with increasing Cr substitution was identified. No clear T{sub MI} can be observed when x>13.5% and the system behaves as an insulator. Such a large, sharp metal-insulator transition and tuneable transition temperature may have potential applications in electronic devices. -- Graphical abstract: The metal-insulator transition temperature (T{sub MI}) was drastically reduced by Cr doping, and is closely related to the distortion of structure. Display Omitted Research highlights: {yields} The metal-insulator transition temperature (T{sub MI}) was drastically reduced by doping Cr into Ca{sub 2}RuO{sub 4} single crystal. {yields} Detailed single crystal structural analysis provided important insight into this structurally-driven metal-insulator transition. {yields} Negative Volume Thermal Expansion (NVTE) was observed with increasing temperature.

  12. Particle trap with dielectric barrier for use in gas insulated transmission lines

    DOE Patents [OSTI]

    Dale, Steinar J. (Monroeville, PA)

    1982-01-01T23:59:59.000Z

    A gas-insulated transmission line includes an outer sheath, an inner conductor within the outer sheath, insulating supports supporting the inner conductor within the outer sheath, and an insulating gas electrically insulating the inner conductor from the outer sheath. An apertured particle trapping electrode is disposed within the outer sheath, and the electrode has a pair of dielectric members secured at each longitudinal end thereof, with the dielectric members extending outwardly from the apertured electrode.

  13. Particle trap with dielectric barrier for use in gas insulated transmission lines

    DOE Patents [OSTI]

    Dale, S.J.

    1982-06-15T23:59:59.000Z

    A gas-insulated transmission line includes an outer sheath, an inner conductor within the outer sheath, insulating supports supporting the inner conductor within the outer sheath, and an insulating gas electrically insulating the inner conductor from the outer sheath. An apertured particle trapping electrode is disposed within the outer sheath, and the electrode has a pair of dielectric members secured at each longitudinal end thereof, with the dielectric members extending outwardly from the apertured electrode. 7 figs.

  14. Distinct Length Scales in the VO{sub 2} Metal–Insulator Transition Revealed by Bi-chromatic Optical Probing

    SciTech Connect (OSTI)

    Wang, Lei [College of William and Mary, Williamsburg, VA (United States); Novikova, Irina B. [College of William and Mary, Williamsburg, VA (United States); Klopf, John M. [JLAB, Newport News, VA (United States); Madaras, Scott E. [JLAB, Newport News, VA (United States); Williams, Gwyn P. [College of William and Mary, Williamsburg, VA (United States); Madaras, Eric [Nasa Langley Research Center, Hampton, VA (United States); Lu, Liwei [Univ. of Virginia, Charlottesville, VA (United States); Wolf, Stuart A. [Univ. of Virginia, Charlottesville, VA (United States); Lukaszew, Rosa A. [College of William and Mary, Williamsburg, VA (United States)

    2014-01-01T23:59:59.000Z

    Upon a heating-induced metal–instulator transition (MIT) in VO{sub 2}, microscopic metallic VO{sub 2} puddles nucleate and coarsen within the insulating matrix. This coexistence of the two phases across the transition spans distinct length scales as their relative domain sizes change. Far-field optical probing is applied to follow the dynamic evolution of the highly correlated metallic domains as the MIT progresses.

  15. Robustness of topological order and formation of quantum well states in topological insulators

    E-Print Network [OSTI]

    Wang, Wei Hua

    Robustness of topological order and formation of quantum well states in topological insulators (like transport measurements) and ultimate application of the topological insulators usually in- volve-resolved photoemission measurements to directly probe the surface state of the prototypical topological insulators, Bi2Se

  16. Topological insulators with inversion symmetry Liang Fu and C. L. Kane

    E-Print Network [OSTI]

    Kane, Charles

    Topological insulators with inversion symmetry Liang Fu and C. L. Kane Department of Physics; revised manuscript received 17 January 2007; published 2 July 2007 Topological insulators are materials insulators. This distinction is characterized by Z2 topological invariants, which characterize the ground

  17. Crossover between weak localization and weak antilocalization in magnetically doped topological insulator

    E-Print Network [OSTI]

    Wang, Wei Hua

    ;Topological insulators (TI) are a new class of quantum materials with insulating bulk enclosedCrossover between weak localization and weak antilocalization in magnetically doped topological insulator Minhao Liu1,* , Jinsong Zhang1,* , Cui-Zu Chang1,2,* , Zuocheng Zhang1 , Xiao Feng2 , Kang Li2

  18. PHYSICAL REVIEW B 83, 035108 (2011) Wannier representation of Z2 topological insulators

    E-Print Network [OSTI]

    Vanderbilt, David

    2011-01-01T23:59:59.000Z

    PHYSICAL REVIEW B 83, 035108 (2011) Wannier representation of Z2 topological insulators Alexey A insulators in two dimensions. It is well known that there is a topological obstruction to the construction of interest in topological insulators. These are materials that are gapped in the bulk, just like ordinary

  19. Superconducting Proximity Effect and Majorana Fermions at the Surface of a Topological Insulator

    E-Print Network [OSTI]

    Kane, Charles

    Superconducting Proximity Effect and Majorana Fermions at the Surface of a Topological Insulator an s-wave superconductor and the surface states of a strong topological insulator. The resulting two by the topological insulator form a nonchiral one-dimensional wire for Majorana fermions, and that circuits formed

  20. Electrically Controllable Surface Magnetism on the Surface of Topological Insulators Jia-Ji Zhu,1

    E-Print Network [OSTI]

    Electrically Controllable Surface Magnetism on the Surface of Topological Insulators Jia-Ji Zhu,1 impurities on the surface of three- dimensional topological insulators, mediated by the helical Dirac named topolo- gical insulator (TI) in a number of materials, such as a two-dimensional (2D) HgTe quantum

  1. Superconductivity in Topological Insulator Sb2Te3 Induced by Pressure

    E-Print Network [OSTI]

    Wang, Wei Hua

    Superconductivity in Topological Insulator Sb2Te3 Induced by Pressure J. Zhu1 *, J. L. Zhang1 *, P superconductivity and topology nature. A s new states of quantum matter, topological insulators are characterized to topological insulators, topological superconductors are expected to have a full pairing gap in the bulk

  2. Realistic Time-Reversal Invariant Topological Insulators with Neutral Atoms N. Goldman,1

    E-Print Network [OSTI]

    Satija, Indu

    Realistic Time-Reversal Invariant Topological Insulators with Neutral Atoms N. Goldman,1 I. Satija topological insulators in alkali atomic gases. We introduce an original method to synthesize a gauge field.10.Jk, 81.16.Ta Topological insulators are a broad class of unconven- tional materials

  3. PHYSICAL REVIEW B 88, 085406 (2013) Topological insulators with commensurate antiferromagnetism

    E-Print Network [OSTI]

    Gilbert, Matthew

    2013-01-01T23:59:59.000Z

    PHYSICAL REVIEW B 88, 085406 (2013) Topological insulators with commensurate antiferromagnetism of the surface states of a 3D topological insulator in the presence of AFM fields with different propagation in the system.1 Nevertheless, the vast majority of topological band insulator states that have been

  4. Spatial fluctuations of helical Dirac fermions on the surface of topological insulators (DMR-0819860)

    E-Print Network [OSTI]

    Petta, Jason

    Spatial fluctuations of helical Dirac fermions on the surface of topological insulators (DMR.Yazdani Princeton Center for Complex Materials (PCCM) Helical Dirac fermions on the surface topological insulators for Dirac electrons in graphene. Bulk defects in a topological insulators play a similar role; however, many

  5. Interaction-Induced Criticality in Z2 Topological Insulators P. M. Ostrovsky,1,2

    E-Print Network [OSTI]

    Fominov, Yakov

    Interaction-Induced Criticality in Z2 Topological Insulators P. M. Ostrovsky,1,2 I. V. Gornyi,1 interaction effects in topological insulators with strong spin-orbit coupling. We find that the interplay-dimensional topological insulator. Remarkably, this interaction-induced criticality, characterized by a universal value

  6. Ultrathin Topological Insulator Bi2Se3 Nanoribbons Exfoliated by Atomic Force

    E-Print Network [OSTI]

    Cui, Yi

    Ultrathin Topological Insulator Bi2Se3 Nanoribbons Exfoliated by Atomic Force Microscopy Seung Sae, Stanford University, Stanford, California 94305 ABSTRACT Ultrathin topological insulator nanostructures), the layered bismuth selenide (Bi2Se3), a single Dirac-cone topological insulator with a large bulk gap, can

  7. Superconductivity on the surface of topological insulators and in two-dimensional noncentrosymmetric materials

    E-Print Network [OSTI]

    Superconductivity on the surface of topological insulators and in two, as it pertains to the surface of a three-dimensional time-reversal symmetric topological band insulator. We also TRS topological band insulator.7­9 In a recent work, Hor et al.10 have reported the observation

  8. Topological Insulators in Three Dimensions Liang Fu, C. L. Kane, and E. J. Mele

    E-Print Network [OSTI]

    Kane, Charles

    Topological Insulators in Three Dimensions Liang Fu, C. L. Kane, and E. J. Mele Department (STI) topological insulators. The WTI are like layered 2D QSH states, but are destroyed by disorder insulator by a Z2 topological invariant [6], analogous to the TKNN invariant of the integer quantum Hall

  9. Topological Insulator in the Presence of Spatially Correlated Disorder Adrian Girschik,1

    E-Print Network [OSTI]

    Rotter, Stefan

    Topological Insulator in the Presence of Spatially Correlated Disorder Adrian Girschik,1 Florian-dimensional topological insulators and on the quantum spin Hall effect which the helical edge states in these systems give can induce a non-trivial phase called the topological Anderson insulator (TAI). In extension

  10. Optical signature of topological insulators Ming-Che Chang1,* and Min-Fong Yang2,

    E-Print Network [OSTI]

    Chang, Ming-Che

    Optical signature of topological insulators Ming-Che Chang1,* and Min-Fong Yang2, 1Department 16 September 2009 The axion coupling in topological insulators couples electric polarization, 73.20. r, 78.20. e I. INTRODUCTION A distinctive property of topological insulators is the ex

  11. The discovery of topological insulators and possible topological superconductors has greatly expanded research into

    E-Print Network [OSTI]

    Weston, Ken

    The discovery of topological insulators and possible topological superconductors has greatly Superconductor, a Copper-doped Topological Insulator: Cu1/4Bi2Se3 Ben J. Lawson1, Y. S. Hor2, J. Mannhart3, Lu Li in CuxBi2Se3 and its implications for pairing in the undoped topological insulator" PRL, 104, 057001

  12. Engineering Time-Reversal Invariant Topological Insulators With Ultra-Cold Atoms N. Goldman,1

    E-Print Network [OSTI]

    Satija, Indu

    Engineering Time-Reversal Invariant Topological Insulators With Ultra-Cold Atoms N. Goldman,1 I: February 1, 2010) Topological insulators are a broad class of unconven- tional phases of matter-reversal violations. Here, we lay out an experiment to realize time-reversal invariant topological insulators in ultra

  13. HgTe-low-field Strained HgTe: a textbook 3D topological insulator

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    HgTe-low-field Strained HgTe: a textbook 3D topological insulator Cl´ement Bouvier, Tristan Meunier martyrs 38054 Grenoble Cedex 9, France (Dated: December 9, 2011) Topological insulators can be seen-conductors and topological- insulators, other contributions make transport data more difficult to unravel. This letter

  14. Bosonic topological insulator in three dimensions and the statistical Witten effect

    E-Print Network [OSTI]

    Bosonic topological insulator in three dimensions and the statistical Witten effect Max A-known that one signature of the three-dimensional electron topological insulator is the Witten effect-odd-integer polarization charge. In the present work, we propose a corre- sponding phenomenon for the topological insulator

  15. Using Strain Gauges to Detect Epoxy Debonding in Insulated Rail Joints

    E-Print Network [OSTI]

    Barkan, Christopher P.L.

    within a control block. Adjacent circuits within the track are separated by insulated rail joints (alsoUsing Strain Gauges to Detect Epoxy Debonding in Insulated Rail Joints Daniel Peltier, Christopher mainline track. These require insulated rail joints every several kilometers in order to electrically

  16. Development of lifetime test procedure for powder evacuated panel insulation. CRADA final report

    SciTech Connect (OSTI)

    Wilkes, K E; Graves, R S; Childs, K W

    1996-03-01T23:59:59.000Z

    This CRADA is between Appliance Research Consortium (ARC) of the Association of Home Appliance Manufacturers (AHAM) and the Lockheed Martin Energy Research Corp. A Powder Evacuated Panel (PEP) is a "super" thermal insulation, having a thermal resistivity (R) substantially above that of existing insulation without the environmental problems of some insulations such as Chlorofluorocarbon (CFC) blown foam.

  17. Sustainable wall construction and exterior insulation retrofit technology process and structure

    DOE Patents [OSTI]

    Vohra, Arun (Bethesda, MD)

    2000-01-01T23:59:59.000Z

    A low-cost process for exterior wall insulation retrofit, or new wall construction by stacking layers of fabric tube filled with insulating material against a wall and covering them with mesh and stucco provides a durable structure with good insulating value.

  18. Mathematical models of magnetic insulation Naoufel BEN ABDALLAH 1 , Pierre DEGOND 1

    E-Print Network [OSTI]

    Méhats, Florian

    Mathematical models of magnetic insulation Naoufel BEN ABDALLAH 1 , Pierre DEGOND 1 and Florian M Palaiseau Cedex, France Abstract The problem of magnetic insulation in a plane diode is discussed. Starting We study the stationary self­consistent problem of magnetic insulation under space­charge lim

  19. Identification of a sound-insulation layer modelled by fuzzy structure theory -Experimental validation

    E-Print Network [OSTI]

    Boyer, Edmond

    Identification of a sound-insulation layer modelled by fuzzy structure theory - Experimental.fernandez@univ-paris-est.fr Abstract One proposes a novel approach to model sound-insulation layers based on the use of the fuzzy in computational models. The keypoint of the method is the construction of a mean elastoacoustic sound-insulation

  20. INFLUENCE OF ANISOTROPIC THERMAL CONDUCTIVITY IN THE APPARATUS INSULATION FOR SUBLIMATION GROWTH OF SIC

    E-Print Network [OSTI]

    INFLUENCE OF ANISOTROPIC THERMAL CONDUCTIVITY IN THE APPARATUS INSULATION FOR SUBLIMATION GROWTH insulation for sublimation growth of SiC: Numerical investigation of heat transfer J¨urgen Geiser, Olaf Klein). As it is not unusual for the thermal insulation of PVT growth apparatus to possess an anisotropic thermal conductivity

  1. Key-Insulated Symmetric Key Cryptography and Mitigating Attacks against Cryptographic Cloud Software

    E-Print Network [OSTI]

    Dodis, Yevgeniy

    Key-Insulated Symmetric Key Cryptography and Mitigating Attacks against Cryptographic Cloud- sociated cryptographic keys in their entirety. In this paper, we investigate key-insulated symmetric key. To illustrate the feasibility of key-insulated symmetric key cryptography, we also report a proof

  2. AIP/123-QED Fuzzy structure theory modeling of sound-insulation layers in complex

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    AIP/123-QED Fuzzy structure theory modeling of sound-insulation layers in complex vibroacoustic France (Dated: September 11, 2008) Fuzzy structure theory for sound-insulation layers 1 hal-00684495 is proposed in developing an elas- toacoustic element useful to model sound-insulation layers for compu

  3. Semi-insulating crystalline silicon formed by oxygen doping during low-temperature chemical vapor deposition

    E-Print Network [OSTI]

    Semi-insulating crystalline silicon formed by oxygen doping during low-temperature chemical vapor) In this letter we demonstrate the use of oxygen as a dopant in silicon to create semi-insulating, crystalline of the films exhibit classical characteristics of space-charge-limited current associated with insulators

  4. Insulators for cold urban areas: The problem of Road Salt Ravi Gorur and Sreeram Venkataraman

    E-Print Network [OSTI]

    Insulators for cold urban areas: The problem of Road Salt Ravi Gorur and Sreeram Venkataraman of insulators in winter due to road salt. We have started a research project at Arizona State University are more concerned with the effect that the road salts have on insulators, both ceramic and composite

  5. Smart Insulating Container with Anti-Theft Features by M2M Tracking

    E-Print Network [OSTI]

    Shinozuka, Masanobu

    Smart Insulating Container with Anti-Theft Features by M2M Tracking Cheng-Ting Lee, Chun-Min ChangChen, Brucelai, TroyChiu}@itri.org.tw, pai.chou@gmail.com Abstract--This paper describes a smart insulating and responsive but also of low overhead. I. INTRODUCTION Smart insulating shipping containers are an important

  6. STOCHASTIC COMPUTATIONAL DYNAMICAL MODEL OF UNCERTAIN STRUCTURE COUPLED WITH AN INSULATION LAYER

    E-Print Network [OSTI]

    Boyer, Edmond

    STOCHASTIC COMPUTATIONAL DYNAMICAL MODEL OF UNCERTAIN STRUCTURE COUPLED WITH AN INSULATION LAYER the effect of insulation layers in complex dynamical systems for low- and medium-frequency ranges such as car booming noise analysis, one introduces a sim- plified stochastic model of insulation layers based

  7. Fluid-Insulator transitions in a system of interacting Bose gas in 1D disordered lattices

    E-Print Network [OSTI]

    Shyamasundar, R.K.

    Fluid-Insulator transitions in a system of interacting Bose gas in 1D disordered lattices insulator, Ander In this seminar, I shall discuss about our recent experimental results where we investigate strengths for which such critical momentum vanishes separating a fluid regime from an insulating one

  8. Insulators, long-range interactions, and genome function Jingping Yang and Victor G Corces

    E-Print Network [OSTI]

    Corces, Victor G.

    Insulators, long-range interactions, and genome function Jingping Yang and Victor G Corces Insulators are DNA­protein complexes that can mediate interactions in cis or trans between different regions together by contacts between specific insulator sites. Here we provide an overview of new evidence that has

  9. Continental insulation, mantle cooling, and the surface area of oceans and continents

    E-Print Network [OSTI]

    Manga, Michael

    Continental insulation, mantle cooling, and the surface area of oceans and continents A. Lenardica May 2005 Abstract It is generally assumed that continents, acting as thermal insulation above. The theory predicts that parameter regimes exist for which increased continental insulation has no effect

  10. Sound-insulation layer modelling in car computational vibroacoustics in the medium-frequency range

    E-Print Network [OSTI]

    Boyer, Edmond

    Sound-insulation layer modelling in car computational vibroacoustics in the medium-frequency range In a previous article, a simplified low- and medium-frequency model for un- certain automotive sound-insulation. In this paper, the insulation simplified model is implemented in an in- dustrial stochastic vibroacoustic model

  11. Supporting Documentation for the 2008 Update to the Insulation Fact Sheet

    SciTech Connect (OSTI)

    Stovall, Therese K [ORNL

    2008-02-01T23:59:59.000Z

    The Insulation Fact Sheet provides consumers for general guidance and recommended insulation levels for their home. This fact sheet has been on-line since 1995 and this update addresses new insulation materials, as well as updated costs for energy and materials.

  12. Topological BF field theory description of topological insulators

    E-Print Network [OSTI]

    Gil Young Cho; Joel E. Moore

    2010-12-03T23:59:59.000Z

    Topological phases of matter are described universally by topological field theories in the same way that symmetry-breaking phases of matter are described by Landau-Ginzburg field theories. We propose that topological insulators in two and three dimensions are described by a version of abelian $BF$ theory. For the two-dimensional topological insulator or quantum spin Hall state, this description is essentially equivalent to a pair of Chern-Simons theories, consistent with the realization of this phase as paired integer quantum Hall effect states. The $BF$ description can be motivated from the local excitations produced when a $\\pi$ flux is threaded through this state. For the three-dimensional topological insulator, the $BF$ description is less obvious but quite versatile: it contains a gapless surface Dirac fermion when time-reversal-symmetry is preserved and yields "axion electrodynamics", i.e., an electromagnetic $E \\cdot B$ term, when time-reversal symmetry is broken and the surfaces are gapped. Just as changing the coefficients and charges of 2D Chern-Simons theory allows one to obtain fractional quantum Hall states starting from integer states, $BF$ theory could also describe (at a macroscopic level) fractional 3D topological insulators with fractional statistics of point-like and line-like objects.

  13. Topological insulating phases in mono and bilayer graphene

    E-Print Network [OSTI]

    Alberto Cortijo; Adolfo G. Grushin; Maria A. H. Vozmediano

    2010-11-20T23:59:59.000Z

    We analyze the influence of different quadratic interactions giving rise to time reversal invariant topological insulating phases in mono and bilayer graphene. We make use of the effective action formalism to determine the dependence of the Chern Simons coefficient on the different interactions.

  14. Disordered Topological Insulators: A Non-Commutative Geometry Perspective

    E-Print Network [OSTI]

    Emil Prodan

    2010-12-22T23:59:59.000Z

    This review deals with strongly disordered topological insulators and covers some recent applications of a well established analytic theory based on the methods of Non-Commutative Geometry (NCG) and developed for the Integer Quantum Hall-Effect. Our main goal is to exemplify how this theory can be used to define topological invariants in the presence of strong disorder, other than the Chern number, and to discuss the physical properties protected by these invariants. Working with two explicit 2-dimensional models, one for a Chern insulator and one for a Quantum spin-Hall insulator, we first give an in-depth account of the key bulk properties of these topological insulators in the clean and disordered regimes. Extensive numerical simulations are employed here. A brisk but self-contained presentation of the non-commutative theory of the Chern number is given and a novel numerical technique to evaluate the non-commutative Chern number is presented. The non-commutative spin-Chern number is defined and the analytic theory together with the explicit calculation of the topological invariants in the presence of strong disorder are used to explain the key bulk properties seen in the numerical experiments presented in the first part of the review.

  15. Heat insulating system for a fast reactor shield slab

    DOE Patents [OSTI]

    Kotora, Jr., James (LaGrange Park, IL); Groh, Edward F. (Naperville, IL); Kann, William J. (Park Ridge, IL); Burelbach, James P. (Glen Ellyn, IL)

    1986-01-01T23:59:59.000Z

    Improved thermal insulation for a nuclear reactor deck comprising many helical coil springs disposed in generally parallel, side-by-side laterally overlapping or interfitted relationship to one another so as to define a three-dimensional composite having both metal and voids between the metal, and enclosure means for holding the composite to the underside of the deck.

  16. alternative insulation materials: Topics by E-print Network

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

    alternative insulation materials First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 1f noise in...

  17. Hall effect at a tunable metal-insulator transition

    E-Print Network [OSTI]

    Teizer, Winfried; Hellman, F.; Dynes, RC.

    2003-01-01T23:59:59.000Z

    Using a rotating magnetic field, the Hall effect in three-dimensional amorphous GdxSi1-x has been measured in the critical regime of the metal-insulator transition for a constant total magnetic field. The Hall coefficient R-0 is negative, indicating...

  18. Design, Simulation and Modeling of Insulated Gate Bipolar Transistor

    E-Print Network [OSTI]

    Gupta, Kaustubh

    2013-07-09T23:59:59.000Z

    The market for Insulated Gate Bipolar Transistor (IGBT) is growing and there is a need for techniques to improve the design, modeling and simulation of IGBT. In this thesis, we first developed a new method to optimize the layout and dimensions...

  19. Cladding Attachment Over Thick Exterior Insulating Sheathing (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-11-01T23:59:59.000Z

    The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of wood-framed walls and mass masonry wall assemblies. The location of the insulation on the exterior of the structure has many direct benefits, including better effective R-value from reduced thermal bridging, better condensation resistance, reduced thermal stress on the structure, as well as other commonly associated improvements such as increased airtightness and improved water management. For thick layers of exterior insulation (more than 1.5 in.), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location. Although the approach has proven effective, there is significant resistance to its widespread implementation due to a lack of research and understanding of the mechanisms involved in the development of the vertical displacement resistance capacity. In addition, the long-term in-service performance of the system has been questioned due to potential creep effects of the assembly under the sustained dead load of the cladding and effects of varying environmental conditions. In addition, the current International Building Code (IBC) and International Residential Code (IRC) do not have a provision that specifically allows this assembly.

  20. Heat insulating system for a fast reactor shield slab

    DOE Patents [OSTI]

    Kotora, J. Jr.; Groh, E.F.; Kann, W.J.; Burelbach, J.P.

    1984-04-10T23:59:59.000Z

    Improved thermal insulation for a nuclear reactor deck comprises many helical coil springs disposed in generally parallel, side-by-side laterally overlapping or interfitted relationship to one another so as to define a three-dimensional composite having both metal and voids between the metal, and enclosure means for holding the composite to the underside of the deck.

  1. System for increasing corona inception voltage of insulating oils

    DOE Patents [OSTI]

    Rohwein, G.J.

    1998-05-19T23:59:59.000Z

    The Corona Inception Voltage of insulating oils is increased by repetitive cycles of prestressing the oil with a voltage greater than the corona inception voltage, and either simultaneously or serially removing byproducts of corona by evacuation and heating the oil. 5 figs.

  2. Moisture Control in Insulated Raised Floor Systems in Southern Louisiana

    E-Print Network [OSTI]

    polyisocyanurate foam, open-cell sprayed polyurethane foams of vary- ing vapor permeance, closed-cell sprayed polyurethane foam, and kraft-faced fiberglass batt insulation. Expected Outcomes This research will result Association Southern Forest Products Association Contact Information Samuel V. Glass USDA Forest Service

  3. Topological BF field theory description of topological insulators

    SciTech Connect (OSTI)

    Cho, Gil Young [Department of Physics, University of California, Berkeley, CA 94720 (United States); Moore, Joel E., E-mail: jemoore@berkeley.edu [Department of Physics, University of California, Berkeley, CA 94720 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2011-06-15T23:59:59.000Z

    Research Highlights: > We show that a BF theory is the effective theory of 2D and 3D topological insulators. > The non-gauge-invariance of the bulk theory yields surface terms for a bosonized Dirac fermion. > The 'axion' term in electromagnetism is correctly obtained from gapped surfaces. > Generalizations to possible fractional phases are discussed in closing. - Abstract: Topological phases of matter are described universally by topological field theories in the same way that symmetry-breaking phases of matter are described by Landau-Ginzburg field theories. We propose that topological insulators in two and three dimensions are described by a version of abelian BF theory. For the two-dimensional topological insulator or quantum spin Hall state, this description is essentially equivalent to a pair of Chern-Simons theories, consistent with the realization of this phase as paired integer quantum Hall effect states. The BF description can be motivated from the local excitations produced when a {pi} flux is threaded through this state. For the three-dimensional topological insulator, the BF description is less obvious but quite versatile: it contains a gapless surface Dirac fermion when time-reversal-symmetry is preserved and yields 'axion electrodynamics', i.e., an electromagnetic E . B term, when time-reversal symmetry is broken and the surfaces are gapped. Just as changing the coefficients and charges of 2D Chern-Simons theory allows one to obtain fractional quantum Hall states starting from integer states, BF theory could also describe (at a macroscopic level) fractional 3D topological insulators with fractional statistics of point-like and line-like objects.

  4. A combined compensation method for the output voltage of an insulated core transformer power supply

    SciTech Connect (OSTI)

    Yang, L.; Yang, J., E-mail: jyang@mail.hust.edu.cn; Liu, K. F.; Qin, B.; Chen, D. Z. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-06-15T23:59:59.000Z

    An insulated core transformer (ICT) power supply is an ideal high-voltage generator for irradiation accelerators with energy lower than 3 MeV. However, there is a significant problem that the structure of the segmented cores leads to an increase in the leakage flux and voltage differences between rectifier disks. A high level of consistency in the output of the disks helps to achieve a compact structure by improving the utilization of both the rectifier components and the insulation distances, and consequently increase the output voltage of the power supply. The output voltages of the disks which are far away from the primary coils need to be improved to reduce their inhomogeneity. In this study, by investigating and comparing the existing compensation methods, a new combined compensation method is proposed, which increases the turns on the secondary coils and employs parallel capacitors to improve the consistency of the disks, while covering the entire operating range of the power supply. This method turns out to be both feasible and effective during the development of an ICT power supply. The non-uniformity of the output voltages of the disks is less than 3.5% from no-load to full-load, and the power supply reaches an output specification of 350 kV/60 mA.

  5. Diamond logic inverter with enhancement-mode metal-insulator-semiconductor field effect transistor

    SciTech Connect (OSTI)

    Liu, J. W., E-mail: liu.jiangwei@nims.go.jp [International Center for Young Scientists (ICYS), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Liao, M. Y.; Imura, M. [Optical and Electronic Materials Unit, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Watanabe, E.; Oosato, H. [Nanofabrication Platform, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Koide, Y., E-mail: koide.yasuo@nims.go.jp [Optical and Electronic Materials Unit, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Nanofabrication Platform, NIMS, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Center of Materials Research for Low Carbon Emission, NIMS, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2014-08-25T23:59:59.000Z

    A diamond logic inverter is demonstrated using an enhancement-mode hydrogenated-diamond metal-insulator-semiconductor field effect transistor (MISFET) coupled with a load resistor. The gate insulator has a bilayer structure of a sputtering-deposited LaAlO{sub 3} layer and a thin atomic-layer-deposited Al{sub 2}O{sub 3} buffer layer. The source-drain current maximum, extrinsic transconductance, and threshold voltage of the MISFET are measured to be ?40.7?mA·mm{sup ?1}, 13.2?±?0.1?mS·mm{sup ?1}, and ?3.1?±?0.1?V, respectively. The logic inverters show distinct inversion (NOT-gate) characteristics for input voltages ranging from 4.0 to ?10.0?V. With increasing the load resistance, the gain of the logic inverter increases from 5.6 to as large as 19.4. The pulse response against the high and low input voltages shows the inversion response with the low and high output voltages.

  6. Insulation of Bi-2212 Superconducting Wire

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

    RESEARCH POSTER PRESENTATION DESIGN 2012 www.PosterPresentations.com Bismuth strontium calcium copper oxide, or Bi 2 Sr 2 CaCu 2 O 8+x (Bi-2212) is a high-temperature...

  7. Limitation of the electron emission in an ion diode with magnetic self-insulation

    SciTech Connect (OSTI)

    Pushkarev, A. I.; Isakova, Yu. I.; Guselnikov, V. I. [Tomsk Polytechnic University, 30, Lenin Ave., Tomsk 634050 (Russian Federation)

    2011-08-15T23:59:59.000Z

    The results of a study of the generation of a pulsed ion beam of gigawatt power formed by a diode with an explosive-emission potential electrode in a mode of magnetic self-insulation are presented. The studies were conducted at the TEMP-4M ion accelerator set in double pulse formation mode: the first pulse was negative (300-500 ns and 100-150 kV) and the second, positive (150 ns and 250-300 kV). The ion current density was 20-40 A/cm{sup 2}; the beam composition was protons and carbon ions. It was shown that plasma is effectively formed over the entire working surface of the graphite potential electrode. During the ion beam generation, a condition of magnetic cutoff of electrons along the entire length of the diode (B/B{sub cr}{>=} 4) is fulfilled. Because of the high drift rate, the residence time of the electrons and protons in the anode-cathode gap is 3-5 ns, while for the C{sup +} carbon ions, it is more than 8 ns. This denotes low efficiency of magnetic self-insulation in a diode of such a design. At the same time, it has been experimentally observed that, during the generation of ion current (second pulse), the electronic component of the total current is suppressed by a factor of 1.5-2 for a strip diode with plane and focusing geometry. A new model of the effect of limiting the electron emission explaining the decrease in the electronic component of the total current in a diode with magnetic self-insulation is proposed.

  8. Quantum insulating states of F=2 cold atoms in optical lattices

    E-Print Network [OSTI]

    Fei Zhou; Gordon W. Semenoff

    2006-11-09T23:59:59.000Z

    In this Letter we study various spin correlated insulating states of F=2 cold atoms in optical lattices. We find that the effective spin exchange interaction due to virtual hopping contains an {\\em octopole} coupling between two neighboring lattice sites. Depending on scattering lengths and numbers of particles per site the ground states are either rotationally invariant dimer or trimer Mott insulators or insulating states with various spin orders. Three spin ordered insulating phases are ferromagnetic, cyclic and nematic Mott insulators. We estimate the phase boundaries for states with different numbers of atoms per lattice site.

  9. Survey and evaluation of available thermal insulation materials for use on solar heating and cooling systems

    SciTech Connect (OSTI)

    Not Available

    1980-03-01T23:59:59.000Z

    This is the final report of a survey and evaluation of insulation materials for use with components of solar heating and cooling systems. The survey was performed by mailing questionnaires to manufacturers of insulation materials and by conducting an extensive literature search to obtain data on relevant properties of various types of insulation materials. The study evaluated insulation materials for active and passive solar heating and cooling systems and for multifunction applications. Primary and secondary considerations for selecting insulation materials for various components of solar heating and cooling systems are presented.

  10. Presented on the European Wind Energy Conference & Exhibition, Brussels, Belgium, March, 31 Network of offshore wind farms connected by gas insulated

    E-Print Network [OSTI]

    Heinemann, Detlev

    ­April, 3 rd 2008. Network of offshore wind farms connected by gas insulated transmission lines? Anja Summary The offshore wind power industry faces two major challenges: the connection of wind farms to the high voltage grid onshore and a smart grid integration of this offshore generated wind power. In terms

  11. Current isolating epitaxial buffer layers for high voltage photodiode array

    DOE Patents [OSTI]

    Morse, Jeffrey D. (Martinez, CA); Cooper, Gregory A. (Pleasant Hill, CA)

    2002-01-01T23:59:59.000Z

    An array of photodiodes in series on a common semi-insulating substrate has a non-conductive buffer layer between the photodiodes and the semi-insulating substrate. The buffer layer reduces current injection leakage between the photodiodes of the array and allows optical energy to be converted to high voltage electrical energy.

  12. The effects of insulation defects on the corrosion of sub-sea super duplex stainless steel process pipes

    SciTech Connect (OSTI)

    Francis, R.; Irwin, J.; Byrne, G.; Warburton, G. [Weir Materials Ltd., Manchester (United Kingdom)

    1995-10-01T23:59:59.000Z

    There is an increasing use of CRAs (corrosion resistant alloys) for subsea flowlines. These pipes carry corrosive fluids at high temperatures and pressures, and insulation is usually, applied to prevent excessive cooling of the process fluids. The present tests were undertaken to investigate the effect of insulation defects on the susceptibility to localized corrosion of a super duplex stainless steel at different internal temperatures. Four different commercial coating systems were tested, Neoprene, EPDM, Polyurethane and Polyurethane foam. The results show that pitting occurred at an average temperature of 55 C for neoprene and EPDM, and at lower temperatures for the other two coatings. The reasons for this are discussed, and the implications for service applications.

  13. The CR 2.0mm (.079") insulation displacement connector features a mounting height as low as

    E-Print Network [OSTI]

    Wedeward, Kevin

    7 The CR 2.0mm (.079") insulation displacement connector features a mounting height as low as 6.9mm") pitch insulation displacement connector allows automatic harness production for connection of UL1007 of misinsertion without being permanently distorted. · Twin U-slot insulation displacement section The insulation

  14. High Performance Window Retrofit

    SciTech Connect (OSTI)

    Shrestha, Som S [ORNL; Hun, Diana E [ORNL; Desjarlais, Andre Omer [ORNL

    2013-12-01T23:59:59.000Z

    The US Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) and Traco partnered to develop high-performance windows for commercial building that are cost-effective. The main performance requirement for these windows was that they needed to have an R-value of at least 5 ft2 F h/Btu. This project seeks to quantify the potential energy savings from installing these windows in commercial buildings that are at least 20 years old. To this end, we are conducting evaluations at a two-story test facility that is representative of a commercial building from the 1980s, and are gathering measurements on the performance of its windows before and after double-pane, clear-glazed units are upgraded with R5 windows. Additionally, we will use these data to calibrate EnergyPlus models that we will allow us to extrapolate results to other climates. Findings from this project will provide empirical data on the benefits from high-performance windows, which will help promote their adoption in new and existing commercial buildings. This report describes the experimental setup, and includes some of the field and simulation results.

  15. Magnetically insulated diode for generating pulsed neutron and gamma ray emissions

    DOE Patents [OSTI]

    Kuswa, G.W.; Leeper, R.J.

    1984-08-16T23:59:59.000Z

    A magnetically insulated diode employs a permanent magnet to generate a magnetic insulating field between a spaced anode and cathode in a vacuum. An ion source is provided in the vicinity of the anode and used to liberate ions for acceleration toward the cathode. The ions are virtually unaffected by the magnetic field and are accelerated into a target for generating a nuclear reaction. The ions and target material may be selected to generate either neutrons or gamma ray emissions from the reaction of the accelerated ions and the target. In another aspect of the invention, a field coil is employed as part of one of the electrodes. A plasma prefill is provided between the electrodes prior to the application of a pulsating potential to one of the electrodes. The field coil multiplies the applied voltage for high diode voltage applications. The diode may be used to generate a /sup 7/Li(p,..gamma..)/sup 8/Be reaction to produce 16.5 MeV gamma emission.

  16. Magnetically insulated diode for generating pulsed neutron and gamma ray emissions

    DOE Patents [OSTI]

    Kuswa, Glenn W. (Albuquerque, NM); Leeper, Ramon J. (Albuquerque, NM)

    1987-01-01T23:59:59.000Z

    A magnetically insulated diode employs a permanent magnet to generate a magnetic insulating field between a spaced anode and cathode in a vacuum. An ion source is provided in the vicinity of the anode and used to liberate ions for acceleration toward the cathode. The ions are virtually unaffected by the magnetic field and are accelerated into a target for generating an nuclear reaction. The ions and target material may be selected to generate either neutrons or gamma ray emissions from the reaction of the accelerated ions and the target. In another aspect of the invention, a field coil is employed as part of one of the electrodes. A plasma prefill is provided between the electrodes prior to the application of a pulsating potential to one of the electrodes. The field coil multiplies the applied voltage for high diode voltage applications. The diode may be used to generate a .sup.7 Li(p,.gamma.).sup.8 Be reaction to produce 16.5 MeV gamma emission.

  17. A supersymmetric holographic dual of a fractional topological insulator

    E-Print Network [OSTI]

    Martin Ammon; Michael Gutperle

    2012-04-10T23:59:59.000Z

    We construct a supersymmetric generalization of the holographic dual of a fractional topological insulator found in \\cite{HoyosBadajoz:2010ac}. This is accomplished by introducing a nontrivial gauge field on the world volume of the probe D7 brane. The BPS equations are derived from the $\\kappa$-symmetry transformation of the probe brane. The BPS equations are shown to reduce to two first oder nonlinear partial differential equations. Solutions of the BPS equations correspond to a probe brane configuration which preserves four of the thirty-two supersymmetries of the $AdS_5\\times S^5$ background. Solutions of the BPS equations which correspond to a holographic fractional topological insulator are obtained numerically.

  18. Dirac Quantization and Fractional Magnetoelectric Effect on Interacting Topological Insulators

    E-Print Network [OSTI]

    K. -S. Park; H. Han

    2010-10-10T23:59:59.000Z

    We use Dirac quantization of flux to study fractional charges and axion angles \\theta in interacting topological insulators with gapless surface modes protected by time-reversal symmetry. In interacting topological insulators, there are two types of fractional axion angle due to conventional odd and nontrivial even flux quantization at the boundary. On even flux quantization in a gapped time reversal invariant system, we show that there is a halved quarter fractional quantum Hall effect on the surface with Hall conductance of p/4q e2/2h with p and q odd integers. The gapless surface modes can be characterized by a nontrivial Z2 anomaly emerged from the even flux quantization. It is suggested that the electron can be regarded as a bound state of fractionally charged quarks confined by a nonabelian color gauge field on the Dirac quantization of complex spinor fields.

  19. Geometrically induced electric polarization in conical topological insulators

    E-Print Network [OSTI]

    Jakson M. Fonseca; Winder A. Moura-Melo; Afranio R. Pereira

    2011-11-29T23:59:59.000Z

    We study the topological magnetoelectric effect on a conical topological insulator when a point charge $q$ is near the cone apex. The Hall current induced on the cone surface and the image charge configuration are determined. We also study a kind of gravitational Aharonov-Bohm effect in this geometry and realize a phase diference betwen the components of the wavefunctions (spinors) upon closed parallel transport around the (singular) cone tip. Concretely, a net current flowing towards cone apex (or botton) shows up, yielding electric polarization of the conical topological insulator. Such an effect may be detected, for instance, by means of the net accumulated Hall charge near the apex. Once it depends only on the geometry of the material (essetially, the cone apperture angle) this may be faced as a microscopic scale realization of (2+1)-dimensional Einstein gravity.

  20. Topological Hofstadter Insulators in a Two-Dimensional Quasicrystal

    E-Print Network [OSTI]

    Duc-Thanh Tran; Alexandre Dauphin; Nathan Goldman; Pierre Gaspard

    2015-03-17T23:59:59.000Z

    We investigate the properties of a two-dimensional quasicrystal in the presence of a uniform magnetic field. In this configuration, the density of states (DOS) displays a Hofstadter butterfly-like structure when it is represented as a function of the magnetic flux per tile. We show that the low-DOS regions of the energy spectrum are associated with chiral edge states, in direct analogy with the Chern insulators realized with periodic lattices. We establish the topological nature of the edge states by computing the topological Chern number associated with the bulk of the quasicrystal. This topological characterization of the non-periodic lattice is achieved through a local (real-space) topological marker. This work opens a route for the exploration of topological insulating materials in a wide range of non-periodic lattice systems, including photonic crystals and cold atoms in optical lattices.