National Library of Energy BETA

Sample records for dielectric loaded structures

  1. DIELECTRIC-LOADED WAVE-GUIDES

    DOE Patents [OSTI]

    Robertson-Shersby-Harvie, R.B.; Mullett, L.B.

    1957-04-23

    This patent presents a particular arrangement for delectric loading of a wave-guide carrying an electromagnetic wave in the E or TM mode of at least the second order, to reduce the power dissipated as the result of conduction loss in the wave-guide walls. To achieve this desirabie result, the effective dielectric constants in the radial direction of adjacent coaxial tubular regions bounded approximateiy by successive nodai surfaces within the electromagnetic field are of two different values alternating in the radial direction, the intermost and outermost regions being of the lower value, and the dielectric constants between nodes are uniform.

  2. Rectangular Dielectric-lined Accelerator Structure

    SciTech Connect (OSTI)

    Wang Changbiao; Yakovlev, V.P.; Hirshfield, J.L.

    2004-12-07

    Results are reported from analysis of a rectangular X-band dielectric-lined accelerator structure operating in the symmetric LSM-11 mode that has a number of favorable attributes, by comparison with dielectric-lined cylindrical structures. These attributes include use of two planar one-piece precision-ground TiN coated dielectric slabs free of joints, open slots along two opposing metallic faces to suppress all anti-symmetric higher-order modes and to facilitate high-speed pumping, and significant reduction of wall losses by use of evanescent vacuum gaps beyond the dielectric slabs. It is shown that a structure operating at 11.424 GHz can be built with a shunt impedance > 60 M{omega}/m using low-loss alumina as the dielectric.

  3. Method of casting patterned dielectric structures

    DOE Patents [OSTI]

    Poco, John F.; Hrubesh, Lawrence W.

    2001-01-01

    A pattern of dielectric structures are formed directly on a substrate in a single step using sol-gel chemistry and molding procedures. The resulting dielectric structures are useful in vacuum applications for electronic devices. Porous, lightweight structures having a high aspect ratio that are suitable for use as spacers between the faceplate and baseplate of a field emission display can be manufactured using this method.

  4. Studies on metal-dielectric plasmonic structures.

    SciTech Connect (OSTI)

    Chettiar, Uday K.; Liu, Zhengtong; Thoreson, Mark D.; Shalaev, Vladimir M.; Drachev, Vladimir P.; Pack, Michael Vern; Kildishev, Alexander V.; Nyga, Piotr

    2010-01-01

    The interaction of light with nanostructured metal leads to a number of fascinating phenomena, including plasmon oscillations that can be harnessed for a variety of cutting-edge applications. Plasmon oscillation modes are the collective oscillation of free electrons in metals under incident light. Previously, surface plasmon modes have been used for communication, sensing, nonlinear optics and novel physics studies. In this report, we describe the scientific research completed on metal-dielectric plasmonic films accomplished during a multi-year Purdue Excellence in Science and Engineering Graduate Fellowship sponsored by Sandia National Laboratories. A variety of plasmonic structures, from random 2D metal-dielectric films to 3D composite metal-dielectric films, have been studied in this research for applications such as surface-enhanced Raman sensing, tunable superlenses with resolutions beyond the diffraction limit, enhanced molecular absorption, infrared obscurants, and other real-world applications.

  5. Structural features of dielectric oxide laser ceramics

    SciTech Connect (OSTI)

    Kaminskii, Alexandr A; Taranov, A V; Khazanov, E N; Akchurin, M Sh

    2012-10-31

    The relation between the transport characteristics of subterahertz thermal phonons and the structural features of singlephase dielectric crystalline laser ceramics based on cubic oxides synthesised in different technological regimes is studied. The effect of plastic deformation on the formation of the grain structure and intergrain layers (boundaries), as well as on the thermophysical, acoustic, optical, and laser characteristics of the materials is analysed. (active media)

  6. Dielectric-Lined High-Gradient Accelerator Structure

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-04-24

    Rectangular particle accelerator structures with internal planar dielectric elements have been studied, with a view towards devising structures with lower surface fields for a given accelerating field, as compared with structures without dielectrics. Success with this concept is expected to allow operation at higher accelerating gradients than otherwise on account of reduced breakdown probabilities. The project involves studies of RF breakdown on amorphous dielectrics in test cavities that could enable high-gradient structures to be built for a future multi-TeV collider. The aim is to determine what the limits are for RF fields at the surfaces of selected dielectrics, and the resulting acceleration gradient that could be achieved in a working structure. The dielectric of principal interest in this study is artificial CVD diamond, on account of its advertised high breakdown field ({approx}2 GV/m for dc), low loss tangent, and high thermal conductivity. Experimental studies at mm-wavelengths on materials and structures for achieving high acceleration gradient were based on the availability of the 34.3 GHz third-harmonic magnicon amplifier developed by Omega-P, and installed at the Yale University Beam Physics Laboratory. Peak power from the magnicon was measured to be about 20 MW in 0.5 {micro}s pulses, with a gain of 54 dB. Experiments for studying RF high-field effects on CVD diamond samples failed to show any evidence after more than 10{sup 5} RF pulses of RF breakdown up to a tangential surface field strength of 153 MV/m; studies at higher fields were not possible due to a degradation in magnicon performance. A rebuild of the tube is underway at this writing. Computed performance for a dielectric-loaded rectangular accelerator structure (DLA) shows highly competitive properties, as compared with an existing all-metal structure. For example, comparisons were made of a DLA structure having two planar CVD diamond elements with a all-metal CERN structure HDS

  7. Three-dimensional periodic dielectric structures having photonic Dirac points

    DOE Patents [OSTI]

    Bravo-Abad, Jorge; Joannopoulos, John D.; Soljacic, Marin

    2015-06-02

    The dielectric, three-dimensional photonic materials disclosed herein feature Dirac-like dispersion in quasi-two-dimensional systems. Embodiments include a face-centered cubic (fcc) structure formed by alternating layers of dielectric rods and dielectric slabs patterned with holes on respective triangular lattices. This fcc structure also includes a defect layer, which may comprise either dielectric rods or a dielectric slab with patterned with holes. This defect layer introduces Dirac cone dispersion into the fcc structure's photonic band structure. Examples of these fcc structures enable enhancement of the spontaneous emission coupling efficiency (the .beta.-factor) over large areas, contrary to the conventional wisdom that the .beta.-factor degrades as the system's size increases. These results enable large-area, low-threshold lasers; single-photon sources; quantum information processing devices; and energy harvesting systems.

  8. Structural assessment of accident loads

    SciTech Connect (OSTI)

    Wagenblast, G.R., Westinghouse Hanford

    1996-05-28

    Structural assessments were made for specific accident loads for specific catch, receiver, and storage tanks. The evaluation herein represents level-of-effort order-of-magnitude estimates of limiting loads that would lead to collapse or rupture of the tank and unmitigated loss of confinement for the waste. Structural capacities were established using failure criteria. Compliance with codes such as ACI, ASCE, ASME, RCRA, UBC, WAC, and DOE Orders was `NOT` maintained. Normal code practice is to prevent failure with margins consistent with expected variations in loads and strengths and confidence in analysis techniques. The evaluation herein represent estimates of code limits without code load factors or code strength reduction factors, and loading beyond such a limit is considered as an onset of some failure mode. The exact nature of the failure mode and its relation to a safe condition is a judgment of the analyst. Consequently, these `RESULTS SHALL NOT BE USED TO ESTABLISH OPERATING OR SAFETY LOAD LIMITS FOR THESE TANKS`.

  9. Chemical pressure effects on structural, dielectric and magnetic...

    Office of Scientific and Technical Information (OSTI)

    Chemical pressure effects on structural, dielectric and magnetic properties of solid solutions Mnsub 3-xCosub xTeOsub 6 Citation Details In-Document Search Title: Chemical ...

  10. Experimentally excellent beaming in a two-layer dielectric structure

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

    Tasolamprou, Anna C.; Zhang, Lei; Kafesaki, Maria; Koschny, Thomas; Soukoulis, Costas M.

    2014-09-15

    We demonstrate both experimentally and theoretically that a two-layer dielectric structure can provide collimation and enhanced transmission of a Gaussian beam passing through it. This is due to formation of surface localized states along the layered structure and the coupling of these states to outgoing propagating waves. As a result, a system of multiple cascading two-layers can sustain the beaming for large propagation distances.

  11. Dielectric barrier structure with hollow electrodes and its recoil effect

    SciTech Connect (OSTI)

    Yu, Shuang; Chen, Qunzhi; Liu, Jiahui; Wang, Kaile; Jiang, Zhe; Sun, Zhili; Zhang, Jue; Fang, Jing

    2015-06-15

    A dielectric barrier structure with hollow electrodes (HEDBS), in which gas flow oriented parallel to the electric field, was proposed. Results showed that with this structure, air can be effectively ignited, forming atmospheric low temperature plasma, and the proposed HEDBS could achieve much higher electron density (5 × 10{sup 15}/cm{sup 3}). It was also found that the flow condition, including outlet diameter and flow rate, played a key role in the evolution of electron density. Optical emission spectroscopy diagnostic results showed that the concentration of reactive species had the same variation trend as the electron density. The simulated distribution of discharge gas flow indicated that the HEDBS had a strong recoil effect on discharge gas, and could efficiently promote generating electron density as well as reactive species.

  12. Method of using sacrificial materials for fabricating internal cavities in laminated dielectric structures

    DOE Patents [OSTI]

    Peterson, Kenneth A.

    2009-02-24

    A method of using sacrificial materials for fabricating internal cavities and channels in laminated dielectric structures, which can be used as dielectric substrates and package mounts for microelectronic and microfluidic devices. A sacrificial mandrel is placed in-between two or more sheets of a deformable dielectric material (e.g., unfired LTCC glass/ceramic dielectric), wherein the sacrificial mandrel is not inserted into a cutout made in any of the sheets. The stack of sheets is laminated together, which deforms the sheet or sheets around the sacrificial mandrel. After lamination, the mandrel is removed, (e.g., during LTCC burnout), thereby creating a hollow internal cavity in the monolithic ceramic structure.

  13. Used Nuclear Fuel Loading and Structural Performance Under Normal...

    Office of Environmental Management (EM)

    Nuclear Fuel Loading and Structural Performance Under Normal Conditions of Transport - Modeling, Simulation and Experimental Integration RD&D Plan Used Nuclear Fuel Loading and ...

  14. Development of High-Gradient Dielectric Laser-Driven Particle Accelerator Structures

    SciTech Connect (OSTI)

    Byer, Robert L.

    2013-11-07

    The thrust of Stanford's program is to conduct research on high-gradient dielectric accelerator structures driven with high repetition-rate, tabletop infrared lasers. The close collaboration between Stanford and SLAC (Stanford Linear Accelerator Center) is critical to the success of this project, because it provides a unique environment where prototype dielectric accelerator structures can be rapidly fabricated and tested with a relativistic electron beam.

  15. Structural and dielectric properties of Gd doped bismuth ferrite-lead titanate

    SciTech Connect (OSTI)

    Mohanty, N. K. Behera, A. K. Satpathy, S. K. Behera, B. Nayak, P.

    2014-04-24

    0.5BiGd{sub x}Fe{sub 1−x}O{sub 3}−0.5PbTiO{sub 3} with x=0.05, 0.10, 0.15, 0.20 composite was prepared by mixed oxide method. Structural characterization was performed by X-ray diffraction and studied that the materials show tetragonal structure at room temperature for all concentration of Gd. Studies of dielectric properties (ε{sub r} and tanδ) of the above compound at different frequencies in a wide range of temperature (25°-500°C) with an impedance analyser revealed that the dielectric constant increases with increase in Gd concentration as well temperature and the compound do not have any dielectric anomaly in the studied frequency and temperature range.

  16. Periodic dielectric structure for production of photonic band gap and method for fabricating the same

    DOE Patents [OSTI]

    Ozbay, Ekmel; Tuttle, Gary; Michel, Erick; Ho, Kai-Ming; Biswas, Rana; Chan, Che-Ting; Soukoulis, Costas

    1995-01-01

    A method for fabricating a periodic dielectric structure which exhibits a photonic band gap. Alignment holes are formed in a wafer of dielectric material having a given crystal orientation. A planar layer of elongate rods is then formed in a section of the wafer. The formation of the rods includes the step of selectively removing the dielectric material of the wafer between the rods. The formation of alignment holes and layers of elongate rods and wafers is then repeated to form a plurality of patterned wafers. A stack of patterned wafers is then formed by rotating each successive wafer with respect to the next-previous wafer, and then placing the successive wafer on the stack. This stacking results in a stack of patterned wafers having a four-layer periodicity exhibiting a photonic band gap.

  17. Periodic dielectric structure for production of photonic band gap and method for fabricating the same

    DOE Patents [OSTI]

    Ozbay, E.; Tuttle, G.; Michel, E.; Ho, K.M.; Biswas, R.; Chan, C.T.; Soukoulis, C.

    1995-04-11

    A method is disclosed for fabricating a periodic dielectric structure which exhibits a photonic band gap. Alignment holes are formed in a wafer of dielectric material having a given crystal orientation. A planar layer of elongate rods is then formed in a section of the wafer. The formation of the rods includes the step of selectively removing the dielectric material of the wafer between the rods. The formation of alignment holes and layers of elongate rods and wafers is then repeated to form a plurality of patterned wafers. A stack of patterned wafers is then formed by rotating each successive wafer with respect to the next-previous wafer, and then placing the successive wafer on the stack. This stacking results in a stack of patterned wafers having a four-layer periodicity exhibiting a photonic band gap. 42 figures.

  18. Sensing Properties of a Fabry-Perot Dielectric Structure and Dimer Nanoparticles

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

    Polemi, A.; Shuford, K. L.

    2012-01-01

    We investigate the use of a Fabry-Perot dielectric structure combined with differently shaped nanoparticles for Surface Enhanced Raman Scattering. In particular, we show how an ideal two-layer Fabry-Perot configuration enhances the local surface field of silver nanoparticles positioned on the surface of the structure. We develop the concept using disc dimers and then extend the discussion to bowtie nanoparticles. The structure is excited by a single emitter, which couples to the nanoparticles through the dielectric layers, producing a wide aperture field that can be used to excite multiple dimers. We show how an array of nanoparticles can be properly arrangedmore » in order to increase the total scattering signal generated from the structure. The layered geometry produces robust field properties in between nanoparticles, making the overall sensing characteristics less sensitive to the interparticle seperation distance and incident polarization.« less

  19. Structure-dielectric properties relationships in copper-substituted magnesium ferrites

    SciTech Connect (OSTI)

    Druc, A.C.; Borhan, A.I.; Nedelcu, G.G.; Leontie, L.; Iordan, A.R.; Palamaru, M.N.

    2013-11-15

    Graphical abstract: - Highlights: • Synthesis of copper substituted magnesium ferrites materials is reported. • A shift from cubic to tetragonal structure starting with x = 0.84 was observed. • The dielectric properties are influenced by Cu-substitution. - Abstract: Nanocrystalline powders of copper-substituted magnesium ferrites with general formula Mg{sub 1−x}Cu{sub x}Fe{sub 2}O{sub 4} (x = 0.00, 0.17, 0.34, 0.50, 0.67, 0.84, 1.00) were prepared for the first time by sol–gel auto-combustion method, using glycine as fuel agent. Solid phase chemical reactions and the occurrence of spinel structure were monitored by using infrared spectroscopy. X-ray diffraction analysis confirmed the spinel single-phase formation. A shift from cubic structure to tetragonal structure starting with x = 0.84 was also observed. Microstructure of the samples was analyzed by scanning electron microscopy and particle size was estimated from the micrographs. Analysis of dielectric properties revealed very low values of dielectric loss at frequencies over 10 MHz.

  20. Design-Load Basis for LANL Structures, Systems, and Components

    SciTech Connect (OSTI)

    I. Cuesta

    2004-09-01

    This document supports the recommendations in the Los Alamos National Laboratory (LANL) Engineering Standard Manual (ESM), Chapter 5--Structural providing the basis for the loads, analysis procedures, and codes to be used in the ESM. It also provides the justification for eliminating the loads to be considered in design, and evidence that the design basis loads are appropriate and consistent with the graded approach required by the Department of Energy (DOE) Code of Federal Regulation Nuclear Safety Management, 10, Part 830. This document focuses on (1) the primary and secondary natural phenomena hazards listed in DOE-G-420.1-2, Appendix C, (2) additional loads not related to natural phenomena hazards, and (3) the design loads on structures during construction.

  1. Structural and dielectric properties of Nd/Ca co-doped bi-ferrite multiferroics

    SciTech Connect (OSTI)

    Kumar, Ashwini E-mail: ashu.dhanda@gmail.com; Sharma, Poorva E-mail: ashu.dhanda@gmail.com; Varshney, Dinesh E-mail: ashu.dhanda@gmail.com

    2014-04-24

    Single-phase polycrystalline samples of Bi{sub 0.8}Nd{sub 0.2−x}Ca{sub x}FeO{sub 3} (x = 0.0, 0.1) were synthesized by chemical coprecipitation method. X-ray diffraction patterns accompanied by Rietveld-refined crystal structure parameters reveal the phase transition of Bi{sub 0.8}Nd{sub 0.1}Ca{sub 0.1}FeO{sub 3} with rhombohedral R3c symmetry to triclinic structure of Bi{sub 0.8}Nd{sub 0.2}FeO{sub 3} sample. Frequency dependence of dielectric constant (ε') and dielectric loss (tanδ), infers enhancement of both ε' (tanδ) in narrow band gap of Nd/Ca co-doped BFO as compare to wide band pristine BFO.

  2. Laser acceleration and deflection of 963 keV electrons with a silicon dielectric structure

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

    Leedle, Kenneth J.; Pease, R. Fabian; Byer, Robert L.; Harris, James S.

    2015-02-12

    Radio frequency particle accelerators are ubiquitous in ultrasmall and ultrafast science, but their size and cost have prompted exploration of compact and scalable alternatives such as the dielectric laser accelerator. We present the first demonstration, to the best of our knowledge, of high gradient laser acceleration and deflection of electrons with a silicon structure. Driven by a 5 nJ, 130 fs mode-locked Ti:sapphire laser at 907 nm wavelength, our devices achieve accelerating gradients in excess of 200 MeV/m and suboptical cycle streaking of 96.30 keV electrons. These results pave the way for high gradient silicon dielectric laser accelerators using commercialmore » lasers and subfemtosecond electron beam experiments.« less

  3. Frequency splitter based on the directional emission from surface modes in dielectric photonic crystal structures

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

    Tasolamprou, Anna C.; Zhang, Lei; Kafesaki, Maria; Koschny, Thomas; Soukoulis, Costas M.

    2015-05-19

    We demonstrate the numerical design and the experimental validation of frequency dependent directional emission from a dielectric photonic crystal structure. The wave propagates through a photonic crystal line-defect waveguide, while a surface layer at the termination of the photonic crystal enables the excitation of surface modes and a subsequent grating layer transforms the surface energy into outgoing propagating waves of the form of a directional beam. The angle of the beam is controlled by the frequency and the structure operates as a frequency splitter in the intermediate and far field region.

  4. Structural, electronic, vibrational, and dielectric properties of LaBGeO{sub 5} from first principles

    SciTech Connect (OSTI)

    Shaltaf, R. Juwhari, H. K.; Hamad, B.; Khalifeh, J.; Rignanese, G.-M.; Gonze, X.

    2014-02-21

    Structural, electronic, vibrational, and dielectric properties of LaBGeO{sub 5} with the stillwellite structure are determined based on ab initio density functional theory. The theoretically relaxed structure is found to agree well with the existing experimental data with a deviation of less than 0.2%. Both the density of states and the electronic band structure are calculated, showing five distinct groups of valence bands. Furthermore, the Born effective charge, the dielectric permittivity tensors, and the vibrational frequencies at the center of the Brillouin zone are all obtained. Compared to existing model calculations, the vibrational frequencies are found in much better agreement with the published experimental infrared and Raman data, with absolute and relative rms values of 6.04?cm{sup ?1}, and 1.81%, respectively. Consequently, numerical values for both the parallel and perpendicular components of the permittivity tensor are established as 3.55 and 3.71 (10.34 and 12.28), respectively, for the high-(low-)frequency limit.

  5. Electric-field-induced local and mesoscale structural changes in polycrystalline dielectrics and ferroelectrics

    SciTech Connect (OSTI)

    Usher, Tedi -Marie; Levin, Igor; Daniels, John E.; Jones, Jacob L.

    2015-10-01

    In this study, the atomic-scale response of dielectrics/ferroelectrics to electric fields is central to their functionality. Here we introduce an in situ characterization method that reveals changes in the local atomic structure in polycrystalline materials under fields. The method employs atomic pair distribution functions (PDFs), determined from X-ray total scattering that depends on orientation relative to the applied field, to probe structural changes over length scales from sub-Ångstrom to several nanometres. The PDF is sensitive to local ionic displacements and their short-range order, a key uniqueness relative to other techniques. The method is applied to representative ferroelectrics, BaTiO3 and Na½Bi½TiO3, and dielectric SrTiO3. For Na½Bi½TiO3, the results reveal an abrupt field-induced monoclinic to rhombohedral phase transition, accompanied by ordering of the local Bi displacements and reorientation of the nanoscale ferroelectric domains. For BaTiO3 and SrTiO3, the local/nanoscale structural changes observed in the PDFs are dominated by piezoelectric lattice strain and ionic polarizability, respectively.

  6. Electric-field-induced local and mesoscale structural changes in polycrystalline dielectrics and ferroelectrics

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

    Usher, Tedi -Marie; Levin, Igor; Daniels, John E.; Jones, Jacob L.

    2015-10-01

    In this study, the atomic-scale response of dielectrics/ferroelectrics to electric fields is central to their functionality. Here we introduce an in situ characterization method that reveals changes in the local atomic structure in polycrystalline materials under fields. The method employs atomic pair distribution functions (PDFs), determined from X-ray total scattering that depends on orientation relative to the applied field, to probe structural changes over length scales from sub-Ångstrom to several nanometres. The PDF is sensitive to local ionic displacements and their short-range order, a key uniqueness relative to other techniques. The method is applied to representative ferroelectrics, BaTiO3 and Na½Bi½TiO3,more » and dielectric SrTiO3. For Na½Bi½TiO3, the results reveal an abrupt field-induced monoclinic to rhombohedral phase transition, accompanied by ordering of the local Bi displacements and reorientation of the nanoscale ferroelectric domains. For BaTiO3 and SrTiO3, the local/nanoscale structural changes observed in the PDFs are dominated by piezoelectric lattice strain and ionic polarizability, respectively.« less

  7. PROBABILISTIC STRUCTURAL RESPONSE OF STRUCTURE UNDER COLLAPSE LOADING

    SciTech Connect (OSTI)

    J. PEPIN; E. RODRIGUEZ; ET AL

    2001-01-05

    Engineers at Los Alamos National Laboratory (LANL) are currently developing the capability to provide a reliability-based structural evaluation technique for performing weapon reliability assessments. To enhance the analyst's confidence with these new methods, an integrated experiment and analysis project has been developed. The uncertainty associated with the collapse response of commercially available spherical marine float is evaluated with the aid of the non-linear explicit dynamics code DYNA3D (Whirley and Engelmann 1988) coupled with the probabilistic code NESSUS (Numerical Evaluation of Stochastic Structures Under Stress) (Thacker et al. 1998). Variations in geometric shape parameters and uncertainties in material parameters are characterized and included in the probabilistic model.

  8. Rapid analysis of scattering from periodic dielectric structures using accelerated Cartesian expansions

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

    Baczewski, Andrew David; Miller, Nicholas C.; Shanker, Balasubramaniam

    2012-03-22

    Here, the analysis of fields in periodic dielectric structures arise in numerous applications of recent interest, ranging from photonic bandgap structures and plasmonically active nanostructures to metamaterials. To achieve an accurate representation of the fields in these structures using numerical methods, dense spatial discretization is required. This, in turn, affects the cost of analysis, particularly for integral-equation-based methods, for which traditional iterative methods require Ο(Ν2) operations, Ν being the number of spatial degrees of freedom. In this paper, we introduce a method for the rapid solution of volumetric electric field integral equations used in the analysis of doubly periodic dielectricmore » structures. The crux of our method is the accelerated Cartesian expansion algorithm, which is used to evaluate the requisite potentials in Ο(Ν) cost. Results are provided that corroborate our claims of acceleration without compromising accuracy, as well as the application of our method to a number of compelling photonics applications.« less

  9. Periodic dielectric structure for production of photonic band gap and devices incorporating the same

    DOE Patents [OSTI]

    Ho, Kai-Ming; Chan, Che-Ting; Soukoulis, Costas

    1994-08-02

    A periodic dielectric structure which is capable of producing a photonic band gap and which is capable of practical construction. The periodic structure is formed of a plurality of layers, each layer being formed of a plurality of rods separated by a given spacing. The material of the rods contrasts with the material between the rods to have a refractive index contrast of at least two. The rods in each layer are arranged with their axes parallel and at a given spacing. Adjacent layers are rotated by 90.degree., such that the axes of the rods in any given layer are perpendicular to the axes in its neighbor. Alternating layers (that is, successive layers of rods having their axes parallel such as the first and third layers) are offset such that the rods of one are about at the midpoint between the rods of the other. A four-layer periocity is thus produced, and successive layers are stacked to form a three-dimensional structure which exhibits a photonic band gap. By virtue of forming the device in layers of elongate members, it is found that the device is susceptible of practical construction.

  10. Load test of the 272W Building high bay roof deck and support structure

    SciTech Connect (OSTI)

    McCoy, R.M.

    1994-09-28

    This reports the results of the Load Test of the 272W Building High Bay Roof Deck and Support Structure.

  11. Effects of coupling and asymmetries on load resilience of IC ITER-like structures

    SciTech Connect (OSTI)

    Bosia, G.; Bremond, S.; Colas, L.

    2005-09-26

    ITER-like structures feature an intrinsic resilience to load variations, which is related to the symmetry of the currents in the two branches of the structure. It has been suggested that the effects of coupling between the array elements would significantly impair the load resilience of the structure. In this paper the effect of inter strap coupling and of however induced electrical array asymmetries on the structure load resilience are quantitatively examined.

  12. Demonstrating Structural Adequacy of Nuclear Power Plant Containment Structures for Beyond Design-Basis Pressure Loadings

    SciTech Connect (OSTI)

    Braverman, J.I.; Morante, R.

    2010-07-18

    ABSTRACT Demonstrating the structural integrity of U.S. nuclear power plant (NPP) containment structures, for beyond design-basis internal pressure loadings, is necessary to satisfy Nuclear Regulatory Commission (NRC) requirements and performance goals. This paper discusses methods for demonstrating the structural adequacy of the containment for beyond design-basis pressure loadings. Three distinct evaluations are addressed: (1) estimating the ultimate pressure capacity of the containment structure (10 CFR 50 and US NRC Standard Review Plan, Section 3.8) ; (2) demonstrating the structural adequacy of the containment subjected to pressure loadings associated with combustible gas generation (10 CFR 52 and 10 CFR 50); and (3) demonstrating the containment structural integrity for severe accidents (10 CFR 52 as well as SECY 90-016, SECY 93-087, and related NRC staff requirements memoranda (SRMs)). The paper describes the technical basis for specific aspects of the methods presented. It also presents examples of past issues identified in licensing activities related to these evaluations.

  13. Structural and dielectric properties of CuO-doped SrTiO{sub 3} ceramics

    SciTech Connect (OSTI)

    Naidu, K. Chandra Babu Sarmash, T. Sofi; Maddaiah, M.; Reddy, V. Narasimha; Subbarao, T.

    2015-06-24

    Copper-doped SrTiO{sub 3} (ST) ceramic powders were processed by solid-state route diffusion (SRD) bulk preparation technique. We reported the effect of Cu{sup +2} ions on the dielectric response of ST and it established the substantial increase in dielectric constant (ε{sub r}) than undoped ST from 303K-673K and low loss (tanδ) for good dielectric applications. In respect of the electrical properties ac- activation energies were computed of range 0.089-0.319eV using lnσ Vs 1/T plots. The microstructure was examined with grain sizes 6-9µm of uniform distribution by field emission scanning electron microscope (FESEM). Some additional phases SrCu{sub 3}Ti{sub 4}O{sub 12} and TiO{sub 2} rutiles were detected by X-ray diffraction technique.

  14. Diamagnetic composite material structure for reducing undesired electromagnetic interference and eddy currents in dielectric wall accelerators and other devices

    DOE Patents [OSTI]

    Caporaso, George J.; Poole, Brian R.; Hawkins, Steven A.

    2015-06-30

    The devices, systems and techniques disclosed here can be used to reduce undesired effects by magnetic field induced eddy currents based on a diamagnetic composite material structure including diamagnetic composite sheets that are separated from one another to provide a high impedance composite material structure. In some implementations, each diamagnetic composite sheet includes patterned conductor layers are separated by a dielectric material and each patterned conductor layer includes voids and conductor areas. The voids in the patterned conductor layers of each diamagnetic composite sheet are arranged to be displaced in position from one patterned conductor layer to an adjacent patterned conductor layer while conductor areas of the patterned conductor layers collectively form a contiguous conductor structure in each diamagnetic composite sheet to prevent penetration by a magnetic field.

  15. High-power radio frequency pulse generation and extration based on wakefield excited by an intense charged particle beam in dielectric-loaded waveguides.

    SciTech Connect (OSTI)

    Gao, F.; High Energy Physics; Illinois Inst. of Tech

    2009-07-24

    Power extraction using a dielectric-loaded (DL) waveguide is a way to generate high-power radio frequency (RF) waves for future particle accelerators, especially for two-beam-acceleration. In a two-beam-acceleration scheme, a low-energy, high-current particle beam is passed through a deceleration section of waveguide (decelerator), where the power from the beam is partially transferred to trailing electromagnetic waves (wakefields); then with a properly designed RF output coupler, the power generated in the decelerator is extracted to an output waveguide, where finally the power can be transmitted and used to accelerate another usually high-energy low-current beam. The decelerator, together with the RF output coupler, is called a power extractor. At Argonne Wakefield Accelerator (AWA), we designed a 7.8GHz power extractor with a circular DL waveguide and tested it with single electron bunches and bunch trains. The output RF frequency (7.8GHz) is the sixth harmonic of the operational frequency (1.3GHz) of the electron gun and the linac at AWA. In single bunch excitation, a 1.7ns RF pulse with 30MW of power was generated by a single 66nC electron bunch passing through the decelerator. In subsequent experiments, by employing different splitting-recombining optics for the photoinjector laser, electron bunch trains were generated and thus longer RF pulses could be successfully generated and extracted. In 16-bunch experiments, 10ns and 22ns RF pulses have been generated and extracted; and in 4-bunch experiments, the maximum power generated was 44MW with 40MW extracted. A 26GHz DL power extractor has also been designed to test this technique in the millimeter-wave range. A power level of 148MW is expected to be generated by a bunch train with a bunch spacing of 769ps and bunch charges of 20nC each. The arrangement for the experiment is illustrated in a diagram. Higher-order-mode (HOM) power extraction has also been explored in a dual-frequency design. By using a bunch

  16. Multilayer dielectric diffraction gratings

    DOE Patents [OSTI]

    Perry, M.D.; Britten, J.A.; Nguyen, H.T.; Boyd, R.; Shore, B.W.

    1999-05-25

    The design and fabrication of dielectric grating structures with high diffraction efficiency used in reflection or transmission is described. By forming a multilayer structure of alternating index dielectric materials and placing a grating structure on top of the multilayer, a diffraction grating of adjustable efficiency, and variable optical bandwidth can be obtained. Diffraction efficiency into the first order in reflection varying between 1 and 98 percent has been achieved by controlling the design of the multilayer and the depth, shape, and material comprising the grooves of the grating structure. Methods for fabricating these gratings without the use of ion etching techniques are described. 7 figs.

  17. Multilayer dielectric diffraction gratings

    DOE Patents [OSTI]

    Perry, Michael D.; Britten, Jerald A.; Nguyen, Hoang T.; Boyd, Robert; Shore, Bruce W.

    1999-01-01

    The design and fabrication of dielectric grating structures with high diffraction efficiency used in reflection or transmission is described. By forming a multilayer structure of alternating index dielectric materials and placing a grating structure on top of the multilayer, a diffraction grating of adjustable efficiency, and variable optical bandwidth can be obtained. Diffraction efficiency into the first order in reflection varying between 1 and 98 percent has been achieved by controlling the design of the multilayer and the depth, shape, and material comprising the grooves of the grating structure. Methods for fabricating these gratings without the use of ion etching techniques are described.

  18. Effect of Zn doping on structural, magnetic and dielectric properties of LaFeO{sub 3} synthesized through sol–gel auto-combustion process

    SciTech Connect (OSTI)

    Bhat, Irshad; Husain, Shahid; Khan, Wasi; Patil, S.I.

    2013-11-15

    Graphical abstract: - Highlights: • We have synthesized the samples of LaFe{sub 1−x}Zn{sub x}O{sub 3} (0 ≤ x ≤ 0.3) using sol–gel auto-combustion process. • The doping of Zn{sup 2+} hugely enhances the dielectric constant (ε′) and it shows a colossal value. • The parent compound LaFeO{sub 3} does not show any relaxation peak, but the substitution of Zn at Fe{sup 3+} site brings the relaxation in the system. • The system shows a peak behavior thereby giving the Debye like dipolar relaxation response. - Abstract: We have studied the structural and dielectric properties of nano-crystalline LaFe{sub 1−x}Zn{sub x}O{sub 3} (0 ≤ x ≤ 0.3) pervoskite samples synthesized through sol–gel auto-combustion technique. X-ray diffraction and FTIR spectroscopy are used to confirm the single phase characteristics. Microstructural features are investigated using scanning electron microscope and compositional analysis is performed through energy dispersive spectroscopy. The average grain sizes, calculated from the Scherrer formula, lie in the range below 30 nm. The hysteresis (M-H) curves display a weak magnetic order and a shift in the hysteresis loops. Dielectric response has been discussed, in the framework of “universal dielectric response” model. The value of dielectric constant (ε′) increases drastically on Zn doping. The dielectric loss factor (ε″) shows Debye like dipolar relaxation behavior. The observed peaks in loss factor (ε″) are attributed to the fact that a strong correlation between the conduction mechanism and the dielectric behavior exists in ferrites.

  19. Gain analysis of higher-order-mode amplification in a dielectric-implanted multi-beam traveling wave structure

    SciTech Connect (OSTI)

    Gee, Anthony; Shin, Young-Min

    2013-01-01

    A multi-beam traveling wave amplifier designed with an overmoded staggered double grating array was examined by small signal analysis combined with simulation. Eigenmode and S-parameter analyses show that the 2cm long slow wave structure (SWS) has 1-5dB insertion loss over the passband (TM31 mode) with ~28% cold bandwidth. Analytic gain calculation indicates that in the SWS, TM31-mode is amplified with 15–20 dB/beam at 64–84GHz with three elliptical beams of 10kV and 150mA/beam, which was compared with particle-in-cell (PIC) simulations. PIC analysis on the analysis of instability with zero-input driving excitations demonstrated that background noises and non-operating lower order modes are noticeably suppressed by implanting equidistant dielectric absorbers; the overmoded structure only allowed the desired 3rd order mode to propagate in the structure. The designed circuit structure can be widely applied to multi-beam devices for high power RF generation.

  20. Modeling of fracture of protective concrete structures under impact loads

    SciTech Connect (OSTI)

    Radchenko, P. A. Batuev, S. P.; Radchenko, A. V.; Plevkov, V. S.

    2015-10-27

    This paper presents results of numerical simulation of interaction between a Boeing 747-400 aircraft and the protective shell of a nuclear power plant. The shell is presented as a complex multilayered cellular structure consisting of layers of concrete and fiber concrete bonded with steel trusses. Numerical simulation was performed three-dimensionally using the original algorithm and software taking into account algorithms for building grids of complex geometric objects and parallel computations. Dynamics of the stress-strain state and fracture of the structure were studied. Destruction is described using a two-stage model that allows taking into account anisotropy of elastic and strength properties of concrete and fiber concrete. It is shown that wave processes initiate destruction of the cellular shell structure; cells start to destruct in an unloading wave originating after the compression wave arrival at free cell surfaces.

  1. Modeling Blast Loading on Buried Reinforced Concrete Structures with Zapotec

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

    Bessette, Greg C.

    2008-01-01

    A coupled Euler-Lagrange solution approach is used to model the response of a buried reinforced concrete structure subjected to a close-in detonation of a high explosive charge. The coupling algorithm is discussed along with a set of benchmark calculations involving detonations in clay and sand.

  2. Load monitoring and compensation strategies for guided-waves based structural health monitoring using piezoelectric transducers

    SciTech Connect (OSTI)

    Roy, Surajit; Ladpli, Purim; Chang, Fu-Kuo

    2015-09-01

    Accurate interpretation of in-situ piezoelectric sensor signals is a challenging task. This article presents the development of a numerical compensation model based on physical insight to address the influence of structural loads on piezo-sensor signals. The model requires knowledge of in-situ strain and temperature distribution in a structure while acquiring sensor signals. The parameters of the numerical model are obtained using experiments on flat aluminum plate under uniaxial tensile loading. It is shown that the model parameters obtained experimentally can be used for different structures, and sensor layout. Furthermore, the combined effects of load and temperature on the piezo-sensor response are also investigated and it is observed that both of these factors have a coupled effect on the sensor signals. It is proposed to obtain compensation model parameters under a range of operating temperatures to address this coupling effect. An important outcome of this study is a new load monitoring concept using in-situ piezoelectric sensor signals to track changes in the load paths in a structure.

  3. Photo-induced tunneling currents in MOS structures with various HfO{sub 2}/SiO{sub 2} stacking dielectrics

    SciTech Connect (OSTI)

    Pang, Chin-Sheng; Hwu, Jenn-Gwo

    2014-04-15

    In this study, the current conduction mechanisms of structures with tandem high-k dielectric in illumination are discussed. Samples of Al/SiO{sub 2}/Si (S), Al/HfO{sub 2}/SiO{sub 2}/Si (H), and Al/3HfO{sub 2}/SiO{sub 2}/Si (3H) were examined. The significant observation of electron traps of sample H compares to sample S is found under the double bias capacitance-voltage (C-V) measurements in illumination. Moreover, the photo absorption sensitivity of sample H is higher than S due to the formation of HfO{sub 2} dielectric layer, which leads to larger numbers of carriers crowded through the sweep of V{sub G} before the domination of tunneling current. Additionally, the HfO{sub 2} dielectric layer would block the electrons passing through oxide from valance band, which would result in less electron-hole (e{sup −}-h{sup +}) pairs recombination effect. Also, it was found that both of the samples S and H show perimeter dependency of positive bias currents due to strong fringing field effect in dark and illumination; while sample 3H shows area dependency of positive bias currents in strong illumination. The non-uniform tunneling current through thin dielectric and through HfO{sub 2} stacking layers are importance to MOS(p) tunneling photo diodes.

  4. Synthesis of polyoxometalate-loaded epoxy composites

    DOE Patents [OSTI]

    Anderson, Benjamin J

    2014-10-07

    The synthesis of a polyoxometalate-loaded epoxy uses a one-step cure by applying an external stimulus to release the acid from the polyoxometalate and thereby catalyze the cure reaction of the epoxy resin. Such polyoxometalate-loaded epoxy composites afford the cured epoxy unique properties imparted by the intrinsic properties of the polyoxometalate. For example, polyoxometalate-loaded epoxy composites can be used as corrosion resistant epoxy coatings, for encapsulation of electronics with improved dielectric properties, and for structural applications with improved mechanical properties.

  5. Influence of spin-orbit effects on structures and dielectric properties of neutral lead clusters

    SciTech Connect (OSTI)

    Götz, D. A. Shayeghi, A.; Schäfer, R.; Johnston, R. L.; Schwerdtfeger, P.

    2014-04-28

    Combining molecular beam electric deflection experiments and global optimization techniques has proven to be a powerful tool for resolving equilibrium structures of neutral metal and semiconductor clusters. Herein, we present electric molecular beam deflection experiments on Pb{sub N} (N = 7–18) clusters. Promising structures are generated using the unbiased Birmingham Cluster Genetic Algorithm approach based on density functional theory. The structures are further relaxed within the framework of two-component density functional theory taking scalar relativistic and spin orbit effects into account. Quantum chemical results are used to model electric molecular beam deflection profiles based on molecular dynamics calculations. Comparison of measured and simulated beam profiles allows the assignment of equilibrium structures for the most cluster sizes in the examined range for the first time. Neutral lead clusters adopt mainly spherical geometries and resemble the structures of lead cluster cations apart from Pb{sub 10}. Their growth pattern deviates strongly from the one observed for tin and germanium clusters.

  6. Cavity resonance absorption in ultra-high bandwidth CRT deflection structure by a resistive load

    DOE Patents [OSTI]

    Dunham, Mark E.; Hudson, Charles L.

    1993-01-01

    An improved ultra-high bandwidth helical coil deflection structure for a hode ray tube is described comprising a first metal member having a bore therein, the metal walls of which form a first ground plane; a second metal member coaxially mounted in the bore of the first metal member and forming a second ground plane; a helical deflection coil coaxially mounted within the bore between the two ground planes; and a resistive load disposed in one end of the bore and electrically connected to the first and second ground planes, the resistive load having an impedance substantially equal to the characteristic impedance of the coaxial line formed by the two coaxial ground planes to inhibit cavity resonance in the structure within the ultra-high bandwidth of operation. Preferably, the resistive load comprises a carbon film on a surface of an end plug in one end of the bore.

  7. Cavity resonance absorption in ultra-high bandwidth CRT deflection structure by a resistive load

    DOE Patents [OSTI]

    Dunham, M.E.; Hudson, C.L.

    1993-05-11

    An improved ultra-high bandwidth helical coil deflection structure for a cathode ray tube is described comprising a first metal member having a bore therein, the metal walls of which form a first ground plane; a second metal member coaxially mounted in the bore of the first metal member and forming a second ground plane; a helical deflection coil coaxially mounted within the bore between the two ground planes; and a resistive load disposed in one end of the bore and electrically connected to the first and second ground planes, the resistive load having an impedance substantially equal to the characteristic impedance of the coaxial line formed by the two coaxial ground planes to inhibit cavity resonance in the structure within the ultra-high bandwidth of operation. Preferably, the resistive load comprises a carbon film on a surface of an end plug in one end of the bore.

  8. Load requirements for maintaining structural integrity of Hanford single-shell tanks during waste feed delivery and retrieval activities

    SciTech Connect (OSTI)

    JULYK, L.J.

    1999-09-22

    This document provides structural load requirements and their basis for maintaining the structural integrity of the Hanford Single-Shell Tanks during waste feed delivery and retrieval activities. The requirements are based on a review of previous requirements and their basis documents as well as load histories with particular emphasis on the proposed lead transfer feed tanks for the privatized vitrification plant.

  9. Structure and microwave dielectric characteristics of lithium-excess Ca{sub 0.6}Nd{sub 0.8/3}TiO{sub 3}/(Li{sub 0.5}Nd{sub 0.5})TiO{sub 3} ceramics

    SciTech Connect (OSTI)

    Zhou, Changrong; Chen, Guohua; Cen, Zhenyong; Yuan, Changlai; Yang, Yun; Li, Weizhou

    2013-11-15

    Graphical abstract: - Highlights: Dense ceramics were fabricated by the conventional solid-state route. Excess-Li addition lowers sintering temperature. Excess-Li addition improves the relative density and microwave dielectric properties. - Abstract: Compositions based on (1?x)Ca{sub 0.6}Nd{sub 8/3}TiO{sub 3}?x(Li{sub 1/2}Nd{sub 1/2})TiO{sub 3} + yLi (CNLNTx + yLi, x = 0.300.60, y = 00.05), suitable for microwave applications have been developed by systematically adding excess lithium in order to tune the microwave dielectric properties and lower sintering temperature. Addition of 0.03 excess-Li simultaneously reduced the sintering temperature and improved the relative density of sintered CNLNTx ceramics. The excess Li addition can compensate the evaporation of Li during sintering process and decrease the secondary phase content. The CNLNTx (x = 0.45) ceramics with 0.03 Li excess sintered at 1190 C have single phase orthorhombic perovskite structure, together with the optimum combination of microwave dielectric properties of ?{sub r} = 129, Q f = 3600 GHz, ?{sub f} = 38 ppm/C. Obviously, excess-Li addition can efficiently decrease the sintering temperature and improve the microwave dielectric properties. The high permittivity and relatively low sintering temperatures of lithium-excess Ca{sub 0.6}Nd{sub 0.8/3}TiO{sub 3}/(Li{sub 0.5}Nd{sub 0.5})TiO{sub 3} ceramics are ideal for the development of low cost ultra-small dielectric loaded antenna.

  10. A Scrutiny of the Equivalent Static Lateral Load Method of Design for Multistory Masonry Structures

    SciTech Connect (OSTI)

    Touqan, A. R.; Helou, S. H.

    2008-07-08

    Building structures with a soft storey are gaining widespread popularity in urban areas due to the scarcity of land and due to the pressing need for wide open spaces at the entrance level. In earthquake prone zones dynamic analysis based on the Equivalent Static Lateral Load method is attractive to the novice and the design codes leave the choice of the analysis procedure up to the discretion of the designer. The following is a comparison of the said method with the more elaborate Response Spectrum Method of analysis as they apply to a repertoire of different structural models. The results clearly show that the former provides similar results of response in structures with gradual change in storey stiffness; while it is over conservative for a bare frame structure. It is however less conservative for structures with a soft storey.

  11. NWTC Researchers Field-Test Advanced Control Turbine Systems to Increase Performance, Decrease Structural Loading of Wind Turbines and Plants

    SciTech Connect (OSTI)

    2015-08-01

    Researchers at the National Renewable Energy Laboratory's (NREL's) National Wind Technology Center (NWTC) are studying component controls, including new advanced actuators and sensors, for both conventional turbines as well as wind plants. This research will help develop innovative control strategies that reduce aerodynamic structural loads and improve performance. Structural loads can cause damage that increase maintenance costs and shorten the life of a turbine or wind plant.

  12. Structure, magnetism, specific heat, and dielectric properties of Eu{sub 2}Ta{sub 2}O{sub 7}

    SciTech Connect (OSTI)

    Kolodiazhnyi, T. Sakurai, H.; Matsushita, Y.

    2014-11-17

    Polycrystalline Eu{sub 2}Ta{sub 2}O{sub 7} containing layered perovskite slabs was prepared and analyzed. Eu{sub 2}Ta{sub 2}O{sub 7} crystallizes in the orthorhombic centrosymmetric Cmcm space group (with unit cell: a?=?3.95156(9), b?=?27.0775(6), and c?=?5.68279(13) ) isomorphous with high-temperature Sr{sub 2}Ta{sub 2}O{sub 7}. Dielectric measurements reveal that, in contrast to Sr{sub 2}Ta{sub 2}O{sub 7} which is ferroelectric below 166?K, Eu{sub 2}Ta{sub 2}O{sub 7} remains paraelectric down to at least 0.45?K and shows no magneto-dielectric coupling. Magnetic data in the 2400?K range indicate an antiferromagnetic phase transition with a sharp susceptibility peak at 2.71(5) K. Further analysis using specific heat measurements reveals that the second magnetic phase transition occurs at 1.10(5) K and dominates the spin entropy of the Eu{sup 2+} 4f{sup 7} ions. The possible origin of the two successive magnetic phase transitions in Eu{sub 2}Ta{sub 2}O{sub 7} requires further studies.

  13. Structural properties and dielectric function of graphene grown by high-temperature sublimation on 4H-SiC(000-1)

    SciTech Connect (OSTI)

    Bouhafs, C. Darakchieva, V.; Persson, I. L.; Persson, P. O. .; Yakimova, R.; Tiberj, A.; Paillet, M.; Zahab, A.-A.; Landois, P.; Juillaguet, S.; Schche, S.; Schubert, M.

    2015-02-28

    Understanding and controlling growth of graphene on the carbon face (C-face) of SiC presents a significant challenge. In this work, we study the structural, vibrational, and dielectric function properties of graphene grown on the C-face of 4H-SiC by high-temperature sublimation in an argon atmosphere. The effect of growth temperature on the graphene number of layers and crystallite size is investigated and discussed in relation to graphene coverage and thickness homogeneity. An amorphous carbon layer at the interface between SiC and the graphene is identified, and its evolution with growth temperature is established. Atomic force microscopy, micro-Raman scattering spectroscopy, spectroscopic ellipsometry, and high-resolution cross-sectional transmission electron microscopy are combined to determine and correlate thickness, stacking order, dielectric function, and interface properties of graphene. The role of surface defects and growth temperature on the graphene growth mechanism and stacking is discussed, and a conclusion about the critical factors to achieve decoupled graphene layers is drawn.

  14. Structural and dielectric properties of Ba{sub 0.7}Sr{sub 0.3}TiO{sub 3} thin films grown by PLD

    SciTech Connect (OSTI)

    James, K. K.; Satish, B.; Jayaraj, M. K.

    2014-01-28

    Ferroelectric thin films of Ba{sub 0.7}Sr{sub 0.3}TiO{sub 3} (BST) were deposited on Si/SiO{sub 2}/TiO{sub 2}/Pt (PtSi) substrate by pulsed laser deposition (PLD). Crystalline films with perovskite structure were obtained without post-deposition annealing. Phase purity of the deposited films was confirmed by x-ray diffraction. The lowest value of FWHM obtained for the film deposited at oxygen pressure 5.410{sup ?4} mbar and substrate temperature 600C, indicates the high crystallinity of the film. The room temperature dielectric constant at 100 kHz was 85. Butterfly loop, which is the characteristic of ferroelectric materials, was obtained in the regime of ?4 to +4V. The leakage current density was nearly 910{sup ?13} Acm{sup ?2}.

  15. Dielectric properties and electronic applications of aerogels

    SciTech Connect (OSTI)

    Hrubesh, L.W.; Pekala, R.W.

    1993-07-01

    Among their other exceptional properties, aerogels also exhibits unusual dielectric properties due to their nano-sized structures and high porosities. For example, our measurements of the dielectric constants and loss tangents for several aerogel varieties at microwave frequencies show that they both vary linearly with the aerogel density, indicating that the dielectric behavior of aerogels is more gas-like than solid-like. We have also measured the dielectric strength of silica aerogels and find that they are better than ceramics for high voltage insulation. The low dielectric constants and loss tangents of aerogels, along with their controllable thermal expansion properties, make them desirable materials for use as thin films in high speed integrated digital and microwave circuitry.

  16. Dielectric Wakefield Accelerator to drive the future FEL Light Source.

    SciTech Connect (OSTI)

    Jing, C.; Power, J.; Zholents, A. )

    2011-04-20

    X-ray free-electron lasers (FELs) are expensive instruments and a large part of the cost of the entire facility is driven by the accelerator. Using a high-energy gain dielectric wake-field accelerator (DWA) instead of the conventional accelerator may provide a significant cost saving and reduction of the facility size. In this article, we investigate using a collinear dielectric wakefield accelerator to provide a high repetition rate, high current, high energy beam to drive a future FEL x-ray light source. As an initial case study, a {approx}100 MV/m loaded gradient, 850 GHz quartz dielectric based 2-stage, wakefield accelerator is proposed to generate a main electron beam of 8 GeV, 50 pC/bunch, {approx}1.2 kA of peak current, 10 x 10 kHz (10 beamlines) in just 100 meters with the fill factor and beam loading considered. This scheme provides 10 parallel main beams with one 100 kHz drive beam. A drive-to-main beam efficiency {approx}38.5% can be achieved with an advanced transformer ratio enhancement technique. rf power dissipation in the structure is only 5 W/cm{sup 2} in the high repetition rate, high gradient operation mode, which is in the range of advanced water cooling capability. Details of study presented in the article include the overall layout, the transform ratio enhancement scheme used to increase the drive to main beam efficiency, main wakefield linac design, cooling of the structure, etc.

  17. Inverse Load Calculation of Wind Turbine Support Structures - A Numerical Verification Using the Comprehensive Simulation Code FAST: Preprint (Revised)

    SciTech Connect (OSTI)

    Pahn, T.; Jonkman, J.; Rolges, R.; Robertson, A.

    2012-11-01

    Physically measuring the dynamic responses of wind turbine support structures enables the calculation of the applied loads using an inverse procedure. In this process, inverse means deriving the inputs/forces from the outputs/responses. This paper presents results of a numerical verification of such an inverse load calculation. For this verification, the comprehensive simulation code FAST is used. FAST accounts for the coupled dynamics of wind inflow, aerodynamics, elasticity and turbine controls. Simulations are run using a 5-MW onshore wind turbine model with a tubular tower. Both the applied loads due to the instantaneous wind field and the resulting system responses are known from the simulations. Using the system responses as inputs to the inverse calculation, the applied loads are calculated, which in this case are the rotor thrust forces. These forces are compared to the rotor thrust forces known from the FAST simulations. The results of these comparisons are presented to assess the accuracy of the inverse calculation. To study the influences of turbine controls, load cases in normal operation between cut-in and rated wind speed, near rated wind speed and between rated and cut-out wind speed are chosen. The presented study shows that the inverse load calculation is capable of computing very good estimates of the rotor thrust. The accuracy of the inverse calculation does not depend on the control activity of the wind turbine.

  18. Ceramic-polymer nanocomposites with increased dielectric permittivity and low dielectric loss

    SciTech Connect (OSTI)

    Bhardwaj, Sumit Paul, Joginder; Raina, K. K.; Thakur, N. S.; Kumar, Ravi

    2014-04-24

    The use of lead free materials in device fabrication is very essential from environmental point of view. We have synthesized the lead free ferroelectric polymer nanocomposite films with increased dielectric properties. Lead free bismuth titanate has been used as active ceramic nanofillers having crystallite size 24nm and PVDF as the polymer matrix. Ferroelectric ?-phase of the polymer composite films was confirmed by X-ray diffraction pattern. Mapping data confirms the homogeneous dispersion of ceramic particles into the polymer matrix. Frequency dependent dielectric constant increases up to 43.4 at 100Hz, whereas dielectric loss decreases with 7 wt% bismuth titanate loading. This high dielectric constant lead free ferroelectric polymer films can be used for energy density applications.

  19. Resonant dielectric metamaterials

    DOE Patents [OSTI]

    Loui, Hung; Carroll, James; Clem, Paul G; Sinclair, Michael B

    2014-12-02

    A resonant dielectric metamaterial comprises a first and a second set of dielectric scattering particles (e.g., spheres) having different permittivities arranged in a cubic array. The array can be an ordered or randomized array of particles. The resonant dielectric metamaterials are low-loss 3D isotropic materials with negative permittivity and permeability. Such isotropic double negative materials offer polarization and direction independent electromagnetic wave propagation.

  20. Load test of the 283W Clearwell Roof Deck and Support Structure

    SciTech Connect (OSTI)

    McCoy, R.M.

    1994-09-12

    The 283W Clearwell roof area was load tested according to the approved load-test procedure, WHC-SD-GN-TP-30015, Revision 0, as modified below. The 283W Clearwell is located in the 200 West Area of the Hanford Site and has the following characteristics: Roof deck - concrete slab supported by columns and walls; Roof membrane - tar and gravel; Roof slope - flat (< 10 deg); and Roof elevation - approximately 6 in. above ground level. The 283W Clearwell was visited in April 1993 for a visual inspection, but could not be inspected because of the confined space requirements. It was revisited in February 1994 for the purpose of writing this test report. Because the roof could not be inspected, a test was determined to be the best way to qualify the roof for personnel access.

  1. Load test of the 277W Building high bay roof deck and support structure

    SciTech Connect (OSTI)

    McCoy, R.M.

    1994-12-02

    The 277W Building high bay roof area was load tested according to the approved load-test procedure, WHC-SD-GN-TP-30015, Revision 1. The 277W Building is located in the 200 West Area of the Hanford Site and has the following characteristics: roof deck -- wood decking supported by 4 x 14 timber purlins; roof membrane -- tar and gravel; roof slope -- flat (<10 deg); and roof elevation -- maximum height of about 63 ft. The 227W Building was visited in March 1994 for a visual inspection. During this inspection, cracked areas were visible in the decking, but it was not possible to determine whether these cracks extended completely through the decking, which is 2-in. thick. The building was revisited in March 1994 for the purpose of writing this test report. Because the roof requires personnel access, a test was determined to be the best way to qualify the roof. The conclusions are that the roof has been qualified for 500-lb total roof load and that the ``No Roof Access`` signs can be changed to ``Roof Access Restricted`` signs.

  2. Load test of the 3701U Building roof deck and support structure

    SciTech Connect (OSTI)

    McCoy, R.M.

    1994-09-14

    The 3701U Building roof area was load tested according to the approved load-test procedure. The 3701U Building is located in the 300 Area of the Hanford Site and has the following characteristics: Roof deck--metal decking supported by steel purlins; Roof membrane--tar and gravel; Roof slope--flat (<10 deg); and Roof elevation--height of about 12.5 ft. The 3701U Building was visited in August 1992 for a visual inspection, but because of insulation an inspection could not be performed. The building was revisited in March 1994 for the purpose of writing this test report. Because the roof could not be inspected, a test was determined to be the best way to qualify the roof for personnel access. The test procedure called for the use of a remotely-controlled robot. The conclusions are that the roof has been qualified for 500-lb total roof load and that the ``No Roof Access`` signs can be changed to ``Roof Access Restricted`` signs.

  3. Structural and dielectric properties of erbium doped BiFeO{sub 3}−PbTiO{sub 3} solid solutions

    SciTech Connect (OSTI)

    Vandana, Singh, Anupinder Singh, Lakhwant Kaur, Anumeet; Dahyia, Sajjan; Chatterjee, Ratnamala

    2014-04-24

    Single phase Er substituted at A-site BiFeO{sub 3}−PbTiO{sub 3} solid solutions were synthesized using solid state reaction route. The calcinations at different temperature reveals that the single and pure tetragonal phase formation has been accomplished at 1000°C. The SEM micrographs did not show any distinguishable change in grain size. The dielectric studies established that the dielectric constant decreases and ferroelectric T{sub c} increases with increase in Er.

  4. Effects of Ni{sup 3+} substitution on structural and temperature dependent dielectrical properties of NdFeO{sub 3}

    SciTech Connect (OSTI)

    Kaur, Pawanpreet Pandit, Rabia Sharma, K. K.; Kumar, Ravi

    2014-04-24

    The polycrystalline samples of NdFe{sub 1−x}Ni{sub x}O{sub 3} (x=0.0, 0.2) were prepared by solid state reaction route, the single phase of powdered samples were ensured by Rietveld refinement of their X-ray diffraction (XRD) data. We have also studied the variation of dielectric constant (ε′), tangent loss (tan δ) and AC conductivity (σ{sub ac}) as a function of frequency and temperature for both the compositions. It is noticed that both the increase in temperature and Ni{sup 3+} ion substitution results in enhancement of dielectric constant, tangent loss and AC conductivity.

  5. Cast dielectric composite linear accelerator

    DOE Patents [OSTI]

    Sanders, David M.; Sampayan, Stephen; Slenes, Kirk; Stoller, H. M.

    2009-11-10

    A linear accelerator having cast dielectric composite layers integrally formed with conductor electrodes in a solventless fabrication process, with the cast dielectric composite preferably having a nanoparticle filler in an organic polymer such as a thermosetting resin. By incorporating this cast dielectric composite the dielectric constant of critical insulating layers of the transmission lines of the accelerator are increased while simultaneously maintaining high dielectric strengths for the accelerator.

  6. Numerical simulation of effective mechanical properties of stochastic composites with consideration for structural evolution under intensive dynamic loading

    SciTech Connect (OSTI)

    Karakulov, Valerii V.; Smolin, Igor Yu. E-mail: skrp@ftf.tsu.ru; Skripnyak, Vladimir A. E-mail: skrp@ftf.tsu.ru

    2014-11-14

    Mechanical behavior of stochastic metal-ceramic composites with the aluminum matrix under high-rate deformation at shock-wave loading is numerically simulated with consideration for structural evolution. Effective values of mechanical parameters of metal-ceramic composites AlB{sub 4}C, AlSiC, and AlAl{sub 2}O{sub 3} are evaluated depending on different concentration of ceramic inclusions.

  7. REVIEW OF PRACTICE FOR DEEPLY EMBEDDED/BURIED NPP STRUCTURES SUBJECT TO SEISMIC LOADINGS.

    SciTech Connect (OSTI)

    XU,J.HOFMAYER,C.MILLER,C.GRAVES,H.

    2004-03-24

    Motivated by many design considerations, several conceptual designs for advanced reactors have proposed that the entire reactor building and a significant portion of the steam generator building will be either partially or completely embedded below grade. For the analysis of seismic events, the soil-structure interaction (SSI) effect and passive earth pressure for these types of deeply embedded structures will have a significant influence on the predicted seismic response. Sponsored by the US Nuclear Regulatory Commission (NRC), Brookhaven National Laboratory (BNL) is carrying out a research program to assess the significance of these proposed design features for advanced reactors, and to evaluate the existing analytical methods to determine their applicability and adequacy in capturing the seismic behavior of the proposed designs. This paper summarizes a literature review performed by BNL to determine the state of knowledge and practice for seismic analyses of deeply embedded and/or buried (DEB) nuclear containment type structures. Included in the paper is BNL's review of the open literature of existing standards, tests, and practices that have been used in the design and analysis of DEB structures. The paper also provides BNL's evaluation of available codes and guidelines with respect to seismic design practice of DEB structures. Based on BNL's review, a discussion is provided to highlight the applicability of the existing technologies for seismic analyses of DEB structures and to identify gaps that may exist in knowledge and potential issues that may require better understanding and further research.

  8. Dielectric strength of parylene HT

    SciTech Connect (OSTI)

    Diaham, S. Bechara, M.; Locatelli, M.-L.; Khazaka, R.; Tenailleau, C.

    2014-02-07

    The dielectric strength of parylene HT (PA-HT) films was studied at room temperature in a wide thickness range from 500 nm to 50 μm and was correlated with nano- and microstructure analyses. X-ray diffraction and polarized optical microscopy have revealed an enhancement of crystallization and spherulites development, respectively, with increasing the material thickness (d). Moreover, a critical thickness d{sub C} (between 5 and 10 μm) is identified corresponding to the beginning of spherulite developments in the films. Two distinct behaviors of the dielectric strength (F{sub B}) appear in the thickness range. For d ≥ d{sub C}, PA-HT films exhibit a decrease in the breakdown field following a negative slope (F{sub B} ∼ d{sup −0.4}), while for d < d{sub C}, it increases with increasing the thickness (F{sub B} ∼ d{sup 0.3}). An optimal thickness d{sub optim} ∼ 5 μm corresponding to a maximum dielectric strength (F{sub B} ∼ 10 MV/cm) is obtained. A model of spherulite development in PA-HT films with increasing the thickness is proposed. The decrease in F{sub B} above d{sub C} is explained by the spherulites development, whereas its increase below d{sub C} is induced by the crystallites growth. An annealing of the material shows both an enhancement of F{sub B} and an increase of the crystallites and spherulites dimensions, whatever the thickness. The breakdown field becomes thickness-independent below d{sub C} showing a strong influence of the nano-scale structural parameters. On the contrary, both nano- and micro-scale structural parameters appear as influent on F{sub B} for d ≥ d{sub C}.

  9. Thermally switchable dielectrics

    DOE Patents [OSTI]

    Dirk, Shawn M.; Johnson, Ross S.

    2013-04-30

    Precursor polymers to conjugated polymers, such as poly(phenylene vinylene), poly(poly(thiophene vinylene), poly(aniline vinylene), and poly(pyrrole vinylene), can be used as thermally switchable capacitor dielectrics that fail at a specific temperature due to the non-conjugated precursor polymer irreversibly switching from an insulator to the conjugated polymer, which serves as a bleed resistor. The precursor polymer is a good dielectric until it reaches a specific temperature determined by the stability of the leaving groups. Conjugation of the polymer backbone at high temperature effectively disables the capacitor, providing a `built-in` safety mechanism for electronic devices.

  10. DIELECTRIC WAKE FIELD RESONATOR ACCELERATOR MODULE

    SciTech Connect (OSTI)

    Hirshfield, Jay L.

    2013-11-06

    Results are presented from experiments, and numerical analysis of wake fields set up by electron bunches passing through a cylindrical or rectangular dielectric-lined structure. These bunches excite many TM-modes, with Ez components of the wake fields sharply localized on the axis of the structure periodically behind the bunches. The experiment with the cylindrical structure, carried out at ATF Brookhaven National Laboratory, used up to three 50 MeV bunches spaced by one wake field period (21 cm) to study the superposition of wake fields by measuring the energy loss of each bunch after it passed through the 53-cm long dielectric element. The millimeter-wave spectrum of radiation excited by the passage of bunches is also studied. Numerical analysis was aimed not only to simulate the behavior of our device, but in general to predict dielectric wake field accelerator performance. It is shown that one needs to match the radius of the cylindrical dielectric channel with the bunch longitudinal rms-length to achieve optimal performance.

  11. Mechanical properties of a structural polyurethane foam and the effect of particulate loading

    SciTech Connect (OSTI)

    Goods, S.H.; Neuschwanger, C.L.; Whinnery, L.L.

    1998-04-01

    The room temperature mechanical properties of a closed-cell, polyurethane encapsulant foam have been measured as a function of foam density. Tests were performed on both unfilled and filler reinforced specimens. Over the range of densities examined, the modulus of the unloaded foam could be described by a power-law relationship with respect to density. This power-law relationship could be explained in terms of the elastic compliance of the cellular structure of the foam using a simple geometric model found in the literature. The collapse stress of the foam was also found to exhibit a power-law relationship with respect to density. Additions of an aluminum powder filler increased the modulus relative to the unfilled foam.

  12. Systems and methods for determining strength of cylindrical structures by internal pressure loading

    DOE Patents [OSTI]

    DeTeresa, Steven John; Groves, Scott Eric; Sanchez, Roberto Joseph; Andrade, William Andrew

    2015-08-04

    In one embodiment, an apparatus, includes: a mandrel; an expansion cylinder, comprising: opposite first and second ends; an inner circumferential surface extending between the ends and characterized by an inner diameter, the inner circumferential surface defining a hollow cavity; an outer circumferential surface extending between the ends and characterized by an outer diameter that is greater than the inner diameter; and a plurality of slots extending from the inner circumferential surface to the outer circumferential surface and latitudinally oriented between the ends; and one or more base plates configured to engage one of the ends of the expansion cylinder. In another embodiment, a method includes: arranging an expansion cylinder inside a test cylinder; arranging a mandrel inside the expansion cylinder; applying a force to the mandrel for exerting a radial force on the expansion cylinder; and detecting one or more indicia of structural failure of the test cylinder.

  13. Molds for cable dielectrics

    DOE Patents [OSTI]

    Roose, L.D.

    1996-12-10

    Molds for use in making end moldings for high-voltage cables are described wherein the dielectric insulator of a cable is heated and molded to conform to a desired shape. As a consequence, high quality substantially bubble-free cable connectors suitable for mating to premanufactured fittings are made. 5 figs.

  14. Molds for cable dielectrics

    DOE Patents [OSTI]

    Roose, Lars D. (Albuquerque, NM)

    1996-01-01

    Molds for use in making end moldings for high-voltage cables are described wherein the dielectric insulator of a cable is heated and molded to conform to a desired shape. As a consequence, high quality substantially bubble-free cable connectors suitable for mating to premanufactured fittings are made.

  15. Surface-PlasmonoDielectric-polaritonic devices and systems

    DOE Patents [OSTI]

    Karalis, Aristeidis; Joannopoulos, John; Soljacic, Marin

    2013-06-25

    There is provided a structure for supporting propagation of surface plasmon polaritons. The structure includes a plasmonic material region and a dielectric material region, disposed adjacent to a selected surface of the plasmonic material region. At least one of the plasmonic material region and the dielectric material region have a dielectric permittivity distribution that is specified as a function of depth through the corresponding material region. This dielectric permittivity distribution is selected to impose prespecified group velocities, v.sub.gj, on a dispersion relation for a surface polaritonic mode of the structure for at least one of a corresponding set of prespecified frequencies, .omega..sub.j, and corresponding set of prespecified wavevectors, where j=1 to N.

  16. Single crystalline Pr{sub 2-x}Y{sub x}O{sub 3} (x=0-2) dielectrics on Si with tailored electronic and crystallographic structure

    SciTech Connect (OSTI)

    Seifarth, O.; Schubert, M. A.; Giussani, A.; Schroeder, T.; Klenov, D. O.; Schmeisser, D.

    2010-11-15

    Crystalline oxides on Si with tailored electronic and crystallographic properties are of importance for the integration of functional oxides or alternative semiconductors to enable novel device concepts in Si microelectronics. We present an electronic band gap study of single crystalline Pr{sub 2-x}Y{sub x}O{sub 3} (0{<=}x{<=}2) heterostructures on Si(111). The perfect solubility of the isomorphic bixbyites Pr{sub 2}O{sub 3} and Y{sub 2}O{sub 3} during molecular beam epitaxy thin film growth on Si enables a linear band gap tuning. Special focus is devoted to the determination of the electronic band offsets across the dielectric/Si interface. In addition, the composition x allows to control the crystallographic lattice parameter where, for example, Pr{sub 0.8}Y{sub 1.2}O{sub 3} enables the growth of fully lattice matched oxide heterostructures on Si.

  17. Load cell

    DOE Patents [OSTI]

    Spletzer, Barry L.

    2001-01-01

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs which can be combined to determine any one of the six general load components.

  18. Load cell

    DOE Patents [OSTI]

    Spletzer, Barry L.

    1998-01-01

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs, each directly proportional to one of the six general load components.

  19. Load cell

    DOE Patents [OSTI]

    Spletzer, B.L.

    1998-12-15

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs, each directly proportional to one of the six general load components. 16 figs.

  20. TWO-CHANNEL DIELECTRIC WAKE FIELD ACCELERATOR

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-05-30

    Experimental results are reported for test beam acceleration and deflection in a two-channel, cm-scale, rectangular dielectric-lined wakefield accelerator structure energized by a 14-MeV drive beam. The dominant waveguide mode of the structure is at {approx}30 GHz, and the structure is configured to exhibit a high transformer ratio ({approx}12:1). Accelerated bunches in the narrow secondary channel of the structure are continuously energized via Cherenkov radiation that is emitted by a drive bunch moving in the wider primary channel. Observed energy gains and losses, transverse deflections, and changes in the test bunch charge distribution compare favorably with predictions of theory.

  1. Cable load sensing device

    DOE Patents [OSTI]

    Beus, Michael J.; McCoy, William G.

    1998-01-01

    Apparatus for sensing the magnitude of a load on a cable as the cable is employed to support the load includes a beam structure clamped to the cable so that a length of the cable lies along the beam structure. A spacer associated with the beam structure forces a slight curvature in a portion of the length of cable under a cable "no-load" condition so that the portion of the length of cable is spaced from the beam structure to define a cable curved portion. A strain gauge circuit including strain gauges is secured to the beam structure by welding. As the cable is employed to support a load the load causes the cable curved portion to exert a force normal to the cable through the spacer and on the beam structure to deform the beam structure as the cable curved portion attempts to straighten under the load. As this deformation takes place, the resistance of the strain gauges is set to a value proportional to the magnitude of the normal strain on the beam structure during such deformation. The magnitude of the normal strain is manipulated in a control device to generate a value equal to the magnitude or weight of the load supported by the cable.

  2. Optical Magnetism from Dielectric Resonator Metamaterials. (Conference...

    Office of Scientific and Technical Information (OSTI)

    Optical Magnetism from Dielectric Resonator Metamaterials. Citation Details In-Document Search Title: Optical Magnetism from Dielectric Resonator Metamaterials. Abstract not ...

  3. Dielectric liquid pulsed-power switch

    DOE Patents [OSTI]

    Christophorou, Loucas G.; Faidas, Homer

    1990-01-01

    This disclosure identifies dielectric liquids for use as opening and closing switching media in pulsed power technology, and describes a dielectric-liquid-pulsed-power switch empolying flashlamps.

  4. Voltage sensor and dielectric material

    DOE Patents [OSTI]

    Yakymyshyn, Christopher Paul; Yakymyshyn, Pamela Jane; Brubaker, Michael Allen

    2006-10-17

    A voltage sensor is described that consists of an arrangement of impedance elements. The sensor is optimized to provide an output ratio that is substantially immune to changes in voltage, temperature variations or aging. Also disclosed is a material with a large and stable dielectric constant. The dielectric constant can be tailored to vary with position or direction in the material.

  5. Effect of ion-beam treatment on structure and fracture resistance of 12Cr1MoV steel under static, cyclic and dynamic loading

    SciTech Connect (OSTI)

    Panin, S. V. Vlasov, I. V. Sergeev, V. P.; Maruschak, P. O.

    2015-10-27

    Features of the structure and properties modification of 12Cr1MoV steel subjected to irradiation by zirconium ion beam have been investigated with the use of optical and electron microscopy as well as microhardness measurement. It has been shown that upon treatment the structure modification occurred across the entire cross-section of specimens with the thickness of 1 mm. Changes in the mechanical properties of these specimens under static, cyclic and impact loading are interpreted in terms of identified structure changes.

  6. Electrodynamic force of dielectric barrier discharge

    SciTech Connect (OSTI)

    Shang, J. S.; Roveda, F.; Huang, P. G.

    2011-06-01

    The periodic electrostatic force of dielectric barrier discharge (DBD) in nitrogen for flow control is investigated by a system of physics-based, two-dimensional model equations. The plasma generation process of DBD is mainly the avalanche growth of electrons through the secondary emission from cathode. Therefore, the charged particle motion of a succession of random micro discharges can be approximated by the drift-diffusion model. The force of DBD generated by charge separation and accumulation over the dielectrics is obtained by solving the model equations with the rigorous media interface boundary condition of Maxwell equations in the time domain. The discharge structure and force components by different electrical permittivity and amplitudes of externally applied electrical potential are delineated and quantified.

  7. Multilayer optical dielectric coating

    DOE Patents [OSTI]

    Emmett, John L.

    1990-01-01

    A highly damage resistant, multilayer, optical reflective coating includes alternating layers of doped and undoped dielectric material. The doping levels are low enough that there are no distinct interfaces between the doped and undoped layers so that the coating has properties nearly identical to the undoped material. The coating is fabricated at high temperature with plasma-assisted chemical vapor deposition techniques to eliminate defects, reduce energy-absorption sites, and maintain proper chemical stoichiometry. A number of differently-doped layer pairs, each layer having a thickness equal to one-quarter of a predetermined wavelength in the material are combined to form a narrowband reflective coating for a predetermined wavelength. Broadband reflectors are made by using a number of narrowband reflectors, each covering a portion of the broadband.

  8. The Dielectric Wall Accelerator

    SciTech Connect (OSTI)

    Caporaso, George J.; Chen, Yu-Jiuan; Sampayan, Stephen E.

    2009-01-01

    The Dielectric Wall Accelerator (DWA), a class of induction accelerators, employs a novel insulating beam tube to impress a longitudinal electric field on a bunch of charged particles. The surface flashover characteristics of this tube may permit the attainment of accelerating gradients on the order of 100 MV/m for accelerating pulses on the order of a nanosecond in duration. A virtual traveling wave of excitation along the tube is produced at any desired speed by controlling the timing of pulse generating modules that supply a tangential electric field to the tube wall. Because of the ability to control the speed of this virtual wave, the accelerator is capable of handling any charge to mass ratio particle; hence it can be used for electrons, protons and any ion. The accelerator architectures, key technologies and development challenges will be described.

  9. Exploration of multi-fold symmetry element-loaded superconducting radio frequency structure for reliable acceleration of low- & medium-beta ion species

    SciTech Connect (OSTI)

    Huang, Shichun; Geng, Rongli

    2015-09-01

    Reliable acceleration of low- to medium-beta proton or heavy ion species is needed for future high current superconducting radio frequency (SRF) accelerators. Due to the high-Q nature of an SRF resonator, it is sensitive to many factors such as electron loading (from either the accelerated beam or from parasitic field emitted electrons), mechanical vibration, and liquid helium bath pressure fluctuation etc. To increase the stability against those factors, a mechanically strong and stable RF structure is desirable. Guided by this consideration, multi-fold symmetry element-loaded SRF structures (MFSEL), cylindrical tanks with multiple (n>=3) rod-shaped radial elements, are being explored. The top goal of its optimization is to improve mechanical stability. A natural consequence of this structure is a lowered ratio of the peak surface electromagnetic field to the acceleration gradient as compared to the traditional spoke cavity. A disadvantage of this new structure is an increased size for a fixed resonant frequency and optimal beta. This paper describes the optimization of the electro-magnetic (EM) design and preliminary mechanical analysis for such structures.

  10. Dielectric behavior of barium modified strontium bismuth titanate ceramic

    SciTech Connect (OSTI)

    Nayak, P.; Badapanda, T.; Anwar, S.; Panigrahi, S.

    2014-04-24

    Barium Modified Strontium Bismuth Titanate(SBT) ceramic with general formula Sr1?xBaxBi4Ti4O15 is prepared by solid state reaction route. The structural analysis of the ceramics was done by X-ray diffraction technique. The X-ray patterns show that all the compositions are of single phase with orthorhombic structure. The temperature dependent dielectric behavior shows that the transition temperature decreases with Ba content but the maximum dielectric constant increases. The decreases of the transition with increase in Ba{sup 2+} ion, may be due to the decrease of orthorhombicity by the incorporation of Ba{sup 2+} ion in SBT lattice.

  11. Manipulating Stress in Cu/low-k Dielectric Nanocomposites

    SciTech Connect (OSTI)

    C Murray; P Besser; E Ryan; J Jordan-Sweet

    2011-12-31

    The interaction of x-rays with organic dielectric materials, which alters their mechanical properties, affects values of stress generated within encapsulated Cu structures. In particular, the evolution of stress within submicron Cu interconnect structures encapsulated by an organosilicate glass can be investigated in situ using synchrotron-based x-ray diffraction. The overall geometry of the composite, along with the amount of irradiation, dictates the change in stress of the Cu features. A quantitative comparison of these findings to mechanical modeling results reveals two modes of modification within the dielectric film: a densification that changes the effective eigenstrain followed by an increase in elastic modulus.

  12. Use of a hard mask for formation of gate and dielectric via nanofilament field emission devices

    DOE Patents [OSTI]

    Morse, Jeffrey D.; Contolini, Robert J.

    2001-01-01

    A process for fabricating a nanofilament field emission device in which a via in a dielectric layer is self-aligned to gate metal via structure located on top of the dielectric layer. By the use of a hard mask layer located on top of the gate metal layer, inert to the etch chemistry for the gate metal layer, and in which a via is formed by the pattern from etched nuclear tracks in a trackable material, a via is formed by the hard mask will eliminate any erosion of the gate metal layer during the dielectric via etch. Also, the hard mask layer will protect the gate metal layer while the gate structure is etched back from the edge of the dielectric via, if such is desired. This method provides more tolerance for the electroplating of a nanofilament in the dielectric via and sharpening of the nanofilament.

  13. Used Nuclear Fuel Loading and Structural Performance Under Normal Conditions of Transport - Modeling, Simulation and Experimental Integration RD&D Plan

    SciTech Connect (OSTI)

    Adkins, Harold E.

    2013-04-01

    Under current U.S. Nuclear Regulatory Commission regulation, it is not sufficient for used nuclear fuel (UNF) to simply maintain its integrity during the storage period, it must maintain its integrity in such a way that it can withstand the physical forces of handling and transportation associated with restaging the fuel and moving it to treatment or recycling facilities, or a geologic repository. Hence it is necessary to understand the performance characteristics of aged UNF cladding and ancillary components under loadings stemming from transport initiatives. Researchers would like to demonstrate that enough information, including experimental support and modeling and simulation capabilities, exists to establish a preliminary determination of UNF structural performance under normal conditions of transport (NCT). This research, development and demonstration (RD&D) plan describes a methodology, including development and use of analytical models, to evaluate loading and associated mechanical responses of UNF rods and key structural components. This methodology will be used to provide a preliminary assessment of the performance characteristics of UNF cladding and ancillary components under rail-related NCT loading. The methodology couples modeling and simulation and experimental efforts currently under way within the Used Fuel Disposition Campaign (UFDC). The methodology will involve limited uncertainty quantification in the form of sensitivity evaluations focused around available fuel and ancillary fuel structure properties exclusively. The work includes collecting information via literature review, soliciting input/guidance from subject matter experts, performing computational analyses, planning experimental measurement and possible execution (depending on timing), and preparing a variety of supporting documents that will feed into and provide the basis for future initiatives. The methodology demonstration will focus on structural performance evaluation of

  14. Controlled deposition of sulphur-containing semiconductor and dielectric nano-structured films on metals in SF{sub 6} ion-ion plasma

    SciTech Connect (OSTI)

    Rafalskyi, Dmytro; Bredin, Jrme; Aanesland, Ane

    2013-12-07

    In the present paper, the deposition processes and formation of films in SF{sub 6} ion-ion plasma, with positive and negative ion flows accelerated to the surface, are investigated. The PEGASES (acronym for Plasma Propulsion with Electronegative GASES) source is used as an ion-ion plasma source capable of generating almost ideal ion-ion plasma with negative ion to electron density ratio more than 2500. It is shown that film deposition in SF{sub 6} ion-ion plasma is very sensitive to the polarity of the incoming ions. The effect is observed for Cu, W, and Pt materials. The films formed on Cu electrodes during negative and positive ion assisted deposition were analyzed. Scanning electron microscope analysis has shown that both positive and negative ion fluxes influence the copper surface and leads to film formation, but with different structures of the surface: the low-energy positive ion bombardment causes the formation of a nano-pored film transparent for ions, while the negative ion bombardment leads to a continuous smooth insulating film. The transversal size of the pores in the porous film varies in the range 50500 nm, and further analysis of the film has shown that the film forms a diode together with the substrate preventing positive charge drain, and positive ions are neutralized by passing through the nano-pores. The film obtained with the negative ion bombardment has an insulating surface, but probably with a multi-layer structure: destroying the top surface layer allows to measure similar diode IV-characteristics as for the nano-pored film case. Basing on results, practical conclusions for the probes and electrodes cleaning in ion-ion SF{sub 6} plasmas have been made. Different applications are proposed for the discovered features of the controlled deposition from ion-ion plasmas, from Li-sulphur rechargeable batteries manufacturing and nanofluidics issues to the applications for microelectronics, including low-k materials formation.

  15. Effect of Dielectric Selection on Sintering Behavior of LTCC

    SciTech Connect (OSTI)

    Krueger, Daniel S.; Agee, Laura; Fadner, Cristie; Duncan, J. Brent

    2010-11-02

    Low Temperature Cofired Ceramic (LTCC) is a versatile ceramic packaging technology. LTCC’s functionality and performance can be enhanced with the incorporation of passive devices such as resistors, capacitors, and inductors into the structure of the substrate. This incorporation, which eliminates surface mount solder joints is desirable for improving system reliability and allows for increased package density. Commercially available dielectrics for embedding capacitors into LTCC are limited and the incorporation of such systems into LTCC substrates poses processing challenges related to material compatibility. This paper will review multiple dielectric systems and techniques for embedding capacitors into LTCC as well as present new data related to the cofiring behavior of LTCC and custom dielectrics.

  16. Alternating-current conductivity and dielectric relaxation of...

    Office of Scientific and Technical Information (OSTI)

    Language: English Subject: 36 MATERIALS SCIENCE; ACTIVATION ENERGY; ALTERNATING CURRENT; COPPER COMPOUNDS; DIELECTRIC MATERIALS; DIELECTRIC PROPERTIES; ELECTRIC CONDUCTIVITY; ...

  17. High Performance Dielectrics - Energy Innovation Portal

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

    High Performance Dielectrics Sandia National Laboratories Contact SNL About This Technology Publications: PDF Document Publication Market Sheet (342 KB) Technology Marketing Summary Current dielectric materials are limited and unable to meet all operating, temperature, response frequency, size, and reliability requirements needed for uncooled high-reliability electronics. To address this problem, scientists at Sandia have developed a method for producing dielectric materials using engineered

  18. LOADING DEVICE

    DOE Patents [OSTI]

    Ohlinger, L.A.

    1958-10-01

    A device is presented for loading or charging bodies of fissionable material into a reactor. This device consists of a car, mounted on tracks, into which the fissionable materials may be placed at a remote area, transported to the reactor, and inserted without danger to the operating personnel. The car has mounted on it a heavily shielded magazine for holding a number of the radioactive bodies. The magazine is of a U-shaped configuration and is inclined to the horizontal plane, with a cap covering the elevated open end, and a remotely operated plunger at the lower, closed end. After the fissionable bodies are loaded in the magazine and transported to the reactor, the plunger inserts the body at the lower end of the magazine into the reactor, then is withdrawn, thereby allowing gravity to roll the remaining bodies into position for successive loading in a similar manner.

  19. Dielectric composite materials and method for preparing

    DOE Patents [OSTI]

    Lauf, Robert J.; Anderson, Kimberly K.; Montgomery, Frederick C.; Collins, Jack L.; Felten, John J.

    2003-07-29

    The invention allows the fabrication of small, dense beads of dielectric materials with selected compositions, which are incorporated into a polymeric matrix for use in capacitors, filters, and the like. A porous, generally spherical bead of hydrous metal oxide containing titanium or zirconium is made by a sol-gel process to form a substantially rigid bead having a generally fine crystallite size and correspondingly finely distributed internal porosity. The resulting gel bead may be washed and hydrothermally reacted with a soluble alkaline earth salt (typically Ba or Sr) at elevated temperature and pressure to convert the bead into a mixed hydrous titanium- or zirconium-alkaline earth oxide while retaining the generally spherical shape. Alternatively, the gel bead may be made by coprecipitation. This mixed oxide bead is then washed, dried and calcined to produce the desired (BaTiO.sub.3, PbTiO.sub.3, SrZrO.sub.3) structure. The sintered beads are incorporated into a selected polymer matrix. The resulting dielectric composite material may be electrically "poled" if desired.

  20. Method for preparing dielectric composite materials

    DOE Patents [OSTI]

    Lauf, Robert J.; Anderson, Kimberly K.; Montgomery, Frederick C.; Collins, Jack L.; Felten, John J.

    2004-11-23

    The invention allows the fabrication of small, dense beads of dielectric materials with selected compositions, which are incorporated into a polymeric matrix for use in capacitors, filters, and the like. A porous, generally spherical bead of hydrous metal oxide containing titanium or zirconium is made by a sol-gel process to form a substantially rigid bead having a generally fine crystallite size and correspondingly finely distributed internal porosity. The resulting gel bead may be washed and hydrothermally reacted with a soluble alkaline earth salt (typically Ba or Sr) at elevated temperature and pressure to convert the bead into a mixed hydrous titanium- or zirconium-alkaline earth oxide while retaining the generally spherical shape. Alternatively, the gel bead may be made by coprecipitation. This mixed oxide bead is then washed, dried and calcined to produce the desired (BaTiO.sub.3, PbTiO.sub.3, SrZrO.sub.3) structure. The sintered beads are incorporated into a selected polymer matrix. The resulting dielectric composite material may be electrically "poled" if desired.

  1. Tailoring dielectric properties of ferroelectric-dielectric multilayers

    SciTech Connect (OSTI)

    Kesim, M. T.; Zhang, J.; Cole, M. W.; Misirlioglu, I. B.

    2014-01-13

    We develop a nonlinear thermodynamic model for multilayer ferroelectric heterostructures that takes into account electrostatic and electromechanical interactions between layers. We concentrate on the effect of relative layer fractions and in-plane thermal stresses on dielectric properties of Ba{sub 0.6}Sr{sub 0.4}TiO{sub 3}-, BaTiO{sub 3}-, and PbZr{sub 0.2}Ti{sub 0.8}O{sub 3} (PZT)-SrTiO{sub 3} (STO) multilayers on Si and c-sapphire. We show that dielectric properties of such multilayers can be significantly enhanced by tailoring the growth/processing temperature and the STO layer fraction. Our computations show that large tunabilities (?90% at 400?kV/cm) are possible in carefully designed barium strontium titanate-STO and PZT-STO even on Si for which there exist substantially large in-plane strains.

  2. Two-phase mixed media dielectric with macro dielectric beads for enhancing resistivity and breakdown strength

    DOE Patents [OSTI]

    Falabella, Steven; Meyer, Glenn A; Tang, Vincent; Guethlein, Gary

    2014-06-10

    A two-phase mixed media insulator having a dielectric fluid filling the interstices between macro-sized dielectric beads packed into a confined volume, so that the packed dielectric beads inhibit electro-hydrodynamically driven current flows of the dielectric liquid and thereby increase the resistivity and breakdown strength of the two-phase insulator over the dielectric liquid alone. In addition, an electrical apparatus incorporates the two-phase mixed media insulator to insulate between electrical components of different electrical potentials. And a method of electrically insulating between electrical components of different electrical potentials fills a confined volume between the electrical components with the two-phase dielectric composite, so that the macro dielectric beads are packed in the confined volume and interstices formed between the macro dielectric beads are filled with the dielectric liquid.

  3. Operation Hardtack. Project 1. 9. Loading on buried simulated structures in high-overpressure regions. Report for April-October 1958

    SciTech Connect (OSTI)

    Bultmann, E.H.; McDonough, G.F.; Sinnamon, G.K.

    1984-10-31

    The objective of this project was to study some of the factors affecting the transmission of air-blast-induced pressure through soil and the loading produced on buried structures by such pressures in the high-pressure region (approximately 250 psi). Factors studied were: (1) the attenuation of pressure in a sand deposit when the water table is a few feet below the ground surface; (2) the effect of duration of positive phase of blast on the pressure transmitted through such a soil; (3) the effect of structure flexibility on the pressure acting on structures buried in such a soil; and (4) the relationship between horizontal and vertical pressures in such a soil. The project employed 43 devices, each a rigid cylinder having one rigid end and one deformable-diaphragm end. The devices were buried at depths ranging from 0 to 20 feet at each of two locations at the Eniwetok Proving Ground. The locations were chosen to give a predicted ground surface overpressure of about 250 psi from each of two shots, Cactus and Koa.

  4. COAXIAL TWO-CHANNEL DIELECTRIC WAKE FIELD ACCELERATOR

    SciTech Connect (OSTI)

    Hirshfield, Jay L.

    2013-04-30

    Theory, computations, and experimental apparatus are presented that describe and are intended to confirm novel properties of a coaxial two-channel dielectric wake field accelerator. In this configuration, an annular drive beam in the outer coaxial channel excites multimode wakefields which, in the inner channel, can accelerate a test beam to an energy much higher than the energy of the drive beam. This high transformer ratio is the result of judicious choice of the dielectric structure parameters, and of the phase separation between drive bunches and test bunches. A structure with cm-scale wakefields has been build for tests at the Argonne Wakefield Accelerator Laboratory, and a structure with mm-scale wakefields has been built for tests at the SLAC FACET facility. Both tests await scheduling by the respective facilities.

  5. LOADED WAVEGUIDES

    DOE Patents [OSTI]

    Mullett, L.B.; Loach, B.G.; Adams, G.L.

    1958-06-24

    >Loaded waveguides are described for the propagation of electromagnetic waves with reduced phase velocities. A rectangular waveguide is dimensioned so as to cut-off the simple H/sub 01/ mode at the operating frequency. The waveguide is capacitance loaded, so as to reduce the phase velocity of the transmitted wave, by connecting an electrical conductor between directly opposite points in the major median plane on the narrower pair of waveguide walls. This conductor may take a corrugated shape or be an aperature member, the important factor being that the electrical length of the conductor is greater than one-half wavelength at the operating frequency. Prepared for the Second U.N. International ConferThe importance of nuclear standards is duscussed. A brief review of the international callaboration in this field is given. The proposal is made to let the International Organization for Standardization (ISO) coordinate the efforts from other groups. (W.D.M.)

  6. End moldings for cable dielectrics

    SciTech Connect (OSTI)

    Roose, L.D.

    1993-12-31

    End moldings for high-voltage cables are described wherein the dielectric insulator of the cable is heated and molded to conform to a desired shape. As a consequence, high quality substantially bubble- free cable connectors suitable for mating to premanufactured fittings are made. Disclosed are a method for making the cable connectors either in the field or in a factory, molds suitable for use with the method, and the molded cable connectors, themselves.

  7. End moldings for cable dielectrics

    DOE Patents [OSTI]

    Roose, Lars D. (Albuquerque, NM)

    2000-01-01

    End moldings for high-voltage cables are described wherein the dielectric insulator of the cable is heated and molded to conform to a desired shape. As a consequence, high quality substantially bubble-free cable connectors suitable for mating to premanufactured fittings are made. Disclosed is a method for making the cable connectors either in the field or in a factory, molds suitable for use with the method, and the molded cable connectors, themselves.

  8. Investigations on spectral and dielectric properties of semi-organic single crystal – morpholinium nitrate

    SciTech Connect (OSTI)

    Arul, H.; Babu, D. Rajan Vizhi, R. Ezhil

    2015-06-24

    Semi organic nonlinear optical crystal Morpholinium nitrate (MN) was synthesized and subsequently grown from the solution by slow evaporation method. The sample has been subjected to powder X-ray diffraction to identify the crystalline nature and the prominent peaks were indexed. The crystal belongs to the monoclinic system with a space group P2{sub 1}/C. Carbon NMR analysis confirms the presence of carbon in the structure of the title compound. Dielectric studies have been carried out on the grown crystal as a function of frequencies at different temperatures. Dielectric constant, dielectric loss and AC conductivity were also calculated.

  9. Dynamic response of Cu4Zr54 metallic glass to high strain rate shock loading: plasticity, spall and atomic-level structures

    SciTech Connect (OSTI)

    Luo, Shengnian; Arman, Bedri; Germann, Timothy C; Cagin, Tahir

    2009-01-01

    We investigate dynamic response of Cu{sub 46}Zr{sub 54} metallic glass under adiabatic planar shock wave loading (one-dimensional strain) wjth molecular dynamics simulations, including Hugoniot (shock) states, shock-induced plasticity and spallation. The Hugoniot states are obtained up to 60 CPa along with the von Mises shear flow strengths, and the dynamic spall strength, at different strain rates and temperatures. The spall strengths likely represent the limiting values achievable in experiments such as laser ablation. For the steady shock states, a clear elastic-plastic transition is identified (e.g., in the shock velocity-particle velocity curve), and the shear strength shows strain-softening. However, the elastic-plastic transition across the shock front displays transient stress overshoot (hardening) above the Hugoniot elastic limit followed by a relatively sluggish relaxation to the steady shock state, and the plastic shock front steepens with increasing shock strength. The local von Mises shear strain analysis is used to characterize local deformation, and the Voronoi tessellation analysis, the corresponding short-range structures at various stages of shock, release, tension and spallation. The plasticity in this glass is manifested as localized shear transformation zones and of local structure rather than thermal origin, and void nucleation occurs preferentially at the highly shear-deformed regions. The Voronoi and shear strain analyses show that the atoms with different local structures are of different shear resistances that lead to shear localization (e.g., the atoms indexed with (0,0,12,0) are most shear-resistant, and those with (0,2,8,1) are highly prone to shear flow). The dynamic changes in local structures are consistent with the observed deformation dynamics.

  10. Temperature and moisture dependence of dielectric constant for silica aerogels

    SciTech Connect (OSTI)

    Hrubesh, L.H., LLNL

    1997-03-01

    The dielectric constants of silica aerogels are among the lowest measured for any solid material. The silica aerogels also exhibit low thermal expansion and are thermally stable to temperatures exceeding 500{degrees}C. However, due to the open porosity and large surface areas for aerogels, their dielectric constants are strongly affected by moisture and temperature. This paper presents data for the dielectric constants of silica aerogels as a function of moisture content at 25{degrees}C, and as a function of temperature, for temperatures in the range from 25{degrees}C to 450{degrees}C. Dielectric constant data are also given for silica aerogels that are heat treated in dry nitrogen at 500{degrees}C, then cooled to 25{degrees}C for measurements in dry air. All measurements are made on bulk aerogel spheres at 22GHz microwave frequency, using a cavity perturbation method. The results of the dependence found here for bulk materials can be inferred to apply also to thin films of silica aerogels having similar nano-structures and densities.

  11. Field-driven Polarization and Domain Dynamics of Ferroelectric/Dielectric

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

    Superlattices | Stanford Synchrotron Radiation Lightsource Field-driven Polarization and Domain Dynamics of Ferroelectric/Dielectric Superlattices Thursday, March 1, 2012 - 10:00am SSRL Conference Room 137-226 Paul G. Evans, Materials Science and Engineering, University of Wisconsin-Madison The atomic-scale periodicity of ferroelectric/dielectric superlattices leads to an exciting variety of structural and dynamic effects in applied electric fields. The richness of these phenomena arises in

  12. Inactivation of Microcystis aeruginosa using dielectric barrier...

    Office of Scientific and Technical Information (OSTI)

    Subject: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 60 APPLIED LIFE SCIENCES; BIOPHYSICS; BIOTECHNOLOGY; DIELECTRIC MATERIALS; ...

  13. Dielectric Resonator Metamasurfaces: Optical Magnetism Emission...

    Office of Scientific and Technical Information (OSTI)

    Optical Magnetism Emission and Optical Devices. Citation Details In-Document Search Title: Dielectric Resonator Metamasurfaces: Optical Magnetism Emission and Optical Devices. ...

  14. Solar cell with silicon oxynitride dielectric layer

    SciTech Connect (OSTI)

    Shepherd, Michael; Smith, David D

    2015-04-28

    Solar cells with silicon oxynitride dielectric layers and methods of forming silicon oxynitride dielectric layers for solar cell fabrication are described. For example, an emitter region of a solar cell includes a portion of a substrate having a back surface opposite a light receiving surface. A silicon oxynitride (SiO.sub.xN.sub.y, 0dielectric layer is disposed on the back surface of the portion of the substrate. A semiconductor layer is disposed on the silicon oxynitride dielectric layer.

  15. Refining the phase diagram of Pb{sub 1−x}La{sub x}(Zr{sub 0.9}Ti{sub 0.1}){sub 1−x/4}O{sub 3} ceramics by structural, dielectric, and anelastic spectroscopy investigations

    SciTech Connect (OSTI)

    Craciun, F. Cordero, F.; Ciuchi, I. V.; Mitoseriu, L.; Galassi, C.

    2015-05-14

    We present the results of dielectric and anelastic spectroscopy measurements, together with X-ray diffraction investigations, which allow us to establish more precisely the phase diagram of Pb{sub 1−x}La{sub x}(Zr{sub 0.9}Ti{sub 0.1}){sub 1−x/4}O{sub 3} (PLZT x/90/10) in the compositional range around the AFE/FE phase boundary (0 < x < 0.04). From structural analysis and polarization-electric field measurements, we have found that the ground state of PLZT samples with x < 0.025 is rhombohedral R3c, while samples with x > 0.032 are antiferroelectric with orthorhombic Pbam structure. In-between, for compositions with 0.025 ≤ x ≤ 0.032, a coexistence of the AFE/FE phases is evidenced. The use of complementary dielectric and anelastic techniques allows to follow the phase transitions shifts throughout all the interesting composition range and to construct the temperature-composition phase diagram. The tilt instability line, separating the R3c and R3m low and high temperature phases, has been evidenced. Moreover, the new transition, associated with the onset of disordered tilting preceding the long range order of the R3c phase, previously found in Zr-rich Pb(Zr,Ti)O{sub 3}, is confirmed in rhombohedral PLZT x/90/10 compositions.

  16. Substrate dielectric effects on graphene field effect transistors

    SciTech Connect (OSTI)

    Hu, Zhaoying; Prasad Sinha, Dhiraj; Ung Lee, Ji, E-mail: jlee1@albany.edu; Liehr, Michael [College of Nanoscale Science and Engineering, The State University of New York at Albany, Albany, New York 12203 (United States)

    2014-05-21

    Graphene is emerging as a promising material for future electronics and optoelectronics applications due to its unique electronic structure. Understanding the graphene-dielectric interaction is of vital importance for the development of graphene field effect transistors (FETs) and other novel graphene devices. Here, we extend the exploration of substrate dielectrics from conventionally used thermally grown SiO{sub 2} and hexagonal boron nitride films to technologically relevant deposited dielectrics used in semiconductor industry. A systematic analysis of morphology and optical and electrical properties was performed to study the effects of different substrates (SiO{sub 2}, HfO{sub 2}, Al{sub 2}O{sub 3}, tetraethyl orthosilicate (TEOS)-oxide, and Si{sub 3}N{sub 4}) on the carrier transport of chemical vapor deposition-derived graphene FET devices. As baseline, we use graphene FETs fabricated on thermal SiO{sub 2} with a relatively high carrier mobility of 10?000 cm{sup 2}/(V s). Among the deposited dielectrics studied, silicon nitride showed the highest mobility, comparable to the properties of graphene fabricated on thermal SiO{sub 2}. We conclude that this result comes from lower long range scattering and short range scattering rates in the nitride compared those in the other deposited films. The carrier fluctuation caused by substrates, however, seems to be the main contributing factor for mobility degradation, as a universal mobility-disorder density product is observed for all the dielectrics examined. The extrinsic doping trend is further confirmed by Raman spectra. We also provide, for the first time, correlation between the intensity ratio of G peak and 2D peak in the Raman spectra to the carrier mobility of graphene for different substrates.

  17. Detecting Energy Modulation in a Dielectric Laser Accelerator

    SciTech Connect (OSTI)

    Lukaczyk, Louis

    2015-08-21

    The Dielectric Laser Acceleration group at SLAC uses micro-fabricated dielectric grating structures and conventional infrared lasers to accelerator electrons. These structures have been estimated to produce an accelerating gradient up to 2 orders of magnitude greater than that produced by conventional RF accelerators. The success of the experiment depends on both the laser damage threshold of the structure and the timing overlap of femtosecond duration laser pulses with the electron bunch. In recent dielectric laser acceleration experiments, the laser pulse was shorter both temporally and spatially than the electron bunch. As a result, the laser is theorized to have interacted with only a small portion of the electron bunch. The detection of this phenomenon, referred to as partial population modulation, required a new approach to the data analysis of the electron energy spectra. A fitting function was designed to separate the accelerated electron population from the un-accelerated electron population. The approach was unsuccessful in detecting acceleration in the partial population modulation data. However, the fitting functions provide an excellent figure of merit for previous data known to contain signatures of acceleration.

  18. HLW Glass Waste Loadings

    Office of Environmental Management (EM)

    HLW Glass Waste Loadings Ian L. Pegg Vitreous State Laboratory The Catholic University of ... (JHCM) technology Factors affecting waste loadings Waste loading requirements ...

  19. Bulk Modulus Capacitor Load Cells

    SciTech Connect (OSTI)

    Dickey, C.E.

    1990-04-01

    Measurement of forces present at various locations within the SSC Model Dipole collared coil assembly is of great practical interest to development engineers. Of particular interest are the forces between coils at the parting plane and forces that exist between coils and pole pieces. It is also desired to observe these forces under the various conditions that a magnet will experience such as: during the collaring process, post-collaring, under the influence of cryogens, and during field excitation. A twenty eight thousandths of an inch thick capacitor load cell which utilizes the hydrostatic condition of a stressed plastic dielectric has been designed. These cells are currently being installed on SSC Model Dipoles. The theory, development, and application of these cells will be discussed.

  20. All-dielectric metasurface analogue of electromagnetically induced...

    Office of Scientific and Technical Information (OSTI)

    induced transparency High Quality Factor Fano-Resonant All-Dielectric ... induced transparency High Quality Factor Fano-Resonant All-Dielectric ...

  1. A Dielectric Relaxometry Study of Segmental Dynamics in PDMS...

    Office of Scientific and Technical Information (OSTI)

    A Dielectric Relaxometry Study of Segmental Dynamics in PDMSBoron Composite and Hybrid Elastomers Citation Details In-Document Search Title: A Dielectric Relaxometry Study of...

  2. High thermal conductivity lossy dielectric using a multi layer configuration

    DOE Patents [OSTI]

    Tiegs, Terry N.; Kiggans, Jr., James O.

    2003-01-01

    Systems and methods are described for loss dielectrics. A loss dielectric includes at least one high dielectric loss layer and at least one high thermal conductivity-electrically insulating layer adjacent the at least one high dielectric loss layer. A method of manufacturing a loss dielectric includes providing at least one high dielectric loss layer and providing at least one high thermal conductivity-electrically insulating layer adjacent the at least one high dielectric loss layer. The systems and methods provide advantages because the loss dielectrics are less costly and more environmentally friendly than the available alternatives.

  3. High Temperature Thin Film Polymer Dielectric Based Capacitors...

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

    Thin Film Polymer Dielectric Based Capacitors for HEV Power Electronic Systems High Temperature Thin Film Polymer Dielectric Based Capacitors for HEV Power Electronic Systems 2009 ...

  4. High thermal conductivity lossy dielectric using co-densified...

    Office of Scientific and Technical Information (OSTI)

    Title: High thermal conductivity lossy dielectric using co-densified multilayer configuration Systems and methods are described for loss dielectrics. A method of manufacturing a ...

  5. Dielectric response of metal/SrTiO{sub 3}/two-dimensional electron liquid heterostructures

    SciTech Connect (OSTI)

    Mikheev, Evgeny; Raghavan, Santosh; Stemmer, Susanne

    2015-08-17

    Maximizing the effective dielectric constant of the gate dielectric stack is important for electrostatically controlling high carrier densities inherent to strongly correlated materials. SrTiO{sub 3} is uniquely suited for this purpose, given its extremely high dielectric constant, which can reach 10{sup 4}. Here, we present a systematic study of the thickness dependence of the dielectric response and leakage of SrTiO{sub 3} that is incorporated into a vertical structure on a high-carrier-density two-dimensional electron liquid (2DEL). A simple model can be used to interpret the data. The results show a need for improved interface control in the design of metal/SrTiO{sub 3}/2DEL devices.

  6. Nano-electromechanical rotation of graphene and giant enhancement in dielectric anisotropy in a liquid crystal

    SciTech Connect (OSTI)

    Basu, Rajratan Kinnamon, Daniel; Garvey, Alfred

    2015-05-18

    A nematic liquid crystal (LC) is doped with dilute concentrations of pristine monolayer graphene (GP) flakes, and the LC + GP hybrids are found to exhibit a dramatic increase in the dielectric anisotropy. Electric field-dependent conductance studies reveal that the graphene flakes follow the nematic director that mechanically rotates on increasing an applied electric field. Further studies show that the ?? electron stacking, between the graphene's honeycomb structure and the LC's benzene rings, stabilizes pseudo-nematic domains that collectively amplify the dielectric anisotropy by improving the orientational order parameter in the nematic phase. These anisotropic domains interact with the external electric field, resulting in a nonzero dielectric anisotropy in the isotropic phase as well. The enhancement in dielectric anisotropy, due to the LCgraphene coupling, is found to have subsequent positive impacts on the LC's orientational threshold field and elasticity that allows the nematic director to respond quicker on switching the electric field off.

  7. Dielectric

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

    Department of Energy Did You Use Federal Tax Credits for Energy Efficiency Last Year? Did You Use Federal Tax Credits for Energy Efficiency Last Year? March 11, 2014 - 9:51am Addthis Report your qualifying energy-efficient home upgrades on your 2013 tax forms. | Photo courtesy of ©iStockphoto.com/Tsuji Report your qualifying energy-efficient home upgrades on your 2013 tax forms. | Photo courtesy of ©iStockphoto.com/Tsuji Erik Hyrkas Erik Hyrkas Media Relations Specialist, Office of

  8. Exciton-dominated dielectric function of atomically thin MoS2 films

    SciTech Connect (OSTI)

    Yu, Yiling; Yu, Yifei; Cai, Yongqing; Li, Wei; Gurarslan, Alper; Peelaers, Hartwin; Aspnes, David E.; Van de Walle, Chris G.; Nguyen, Nhan V.; Zhang, Yong -Wei; Cao, Linyou

    2015-11-24

    We systematically measure the dielectric function of atomically thin MoS2 films with different layer numbers and demonstrate that excitonic effects play a dominant role in the dielectric function when the films are less than 5–7 layers thick. The dielectric function shows an anomalous dependence on the layer number. It decreases with the layer number increasing when the films are less than 5–7 layers thick but turns to increase with the layer number for thicker films. We show that this is because the excitonic effect is very strong in the thin MoS2 films and its contribution to the dielectric function may dominate over the contribution of the band structure. We also extract the value of layer-dependent exciton binding energy and Bohr radius in the films by fitting the experimental results with an intuitive model. The dominance of excitonic effects is in stark contrast with what reported at conventional materials whose dielectric functions are usually dictated by band structures. Lastly, the knowledge of the dielectric function may enable capabilities to engineer the light-matter interactions of atomically thin MoS2 films for the development of novel photonic devices, such as metamaterials, waveguides, light absorbers, and light emitters.

  9. Exciton-dominated dielectric function of atomically thin MoS2 films

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

    Yu, Yiling; Yu, Yifei; Cai, Yongqing; Li, Wei; Gurarslan, Alper; Peelaers, Hartwin; Aspnes, David E.; Van de Walle, Chris G.; Nguyen, Nhan V.; Zhang, Yong -Wei; et al

    2015-11-24

    We systematically measure the dielectric function of atomically thin MoS2 films with different layer numbers and demonstrate that excitonic effects play a dominant role in the dielectric function when the films are less than 5–7 layers thick. The dielectric function shows an anomalous dependence on the layer number. It decreases with the layer number increasing when the films are less than 5–7 layers thick but turns to increase with the layer number for thicker films. We show that this is because the excitonic effect is very strong in the thin MoS2 films and its contribution to the dielectric function maymore » dominate over the contribution of the band structure. We also extract the value of layer-dependent exciton binding energy and Bohr radius in the films by fitting the experimental results with an intuitive model. The dominance of excitonic effects is in stark contrast with what reported at conventional materials whose dielectric functions are usually dictated by band structures. Lastly, the knowledge of the dielectric function may enable capabilities to engineer the light-matter interactions of atomically thin MoS2 films for the development of novel photonic devices, such as metamaterials, waveguides, light absorbers, and light emitters.« less

  10. Overview of High Power Vacuum Dry RF Load Designs

    SciTech Connect (OSTI)

    Krasnykh, Anatoly

    2015-08-27

    A specific feature of RF linacs based on the pulsed traveling wave (TW) mode of operation is that only a portion of the RF energy is used for the beam acceleration. The residual RF energy has to be terminated into an RF load. Higher accelerating gradients require higher RF sources and RF loads, which can stably terminate the residual RF power. RF feeders (from the RF source though the accelerating section to the load) are vacuumed to transmit multi-megawatt high power RF. This overview will outline vacuumed RF loads only. A common method to terminate multi-MW RF power is to use circulated water (or other liquid) as an absorbing medium. A solid dielectric interface (a high quality ceramic) is required to separate vacuum and liquid RF absorber mediums. Using such RF load approaches in TW linacs is troubling because there is a fragile ceramic window barrier and a failure could become catastrophic for linac vacuum and RF systems. Traditional loads comprising of a ceramic disk have limited peak and average power handling capability and are therefore not suitable for high gradient TW linacs. This overview will focus on ''vacuum dry'' or ''all-metal'' loads that do not employ any dielectric interface between vacuum and absorber. The first prototype is an original design of RF loads for the Stanford Two-Mile Accelerator.

  11. Virtual gap dielectric wall accelerator

    DOE Patents [OSTI]

    Caporaso, George James; Chen, Yu-Jiuan; Nelson, Scott; Sullivan, Jim; Hawkins, Steven A

    2013-11-05

    A virtual, moving accelerating gap is formed along an insulating tube in a dielectric wall accelerator (DWA) by locally controlling the conductivity of the tube. Localized voltage concentration is thus achieved by sequential activation of a variable resistive tube or stalk down the axis of an inductive voltage adder, producing a "virtual" traveling wave along the tube. The tube conductivity can be controlled at a desired location, which can be moved at a desired rate, by light illumination, or by photoconductive switches, or by other means. As a result, an impressed voltage along the tube appears predominantly over a local region, the virtual gap. By making the length of the tube large in comparison to the virtual gap length, the effective gain of the accelerator can be made very large.

  12. Dielectric gas mixtures containing sulfur hexafluoride

    DOE Patents [OSTI]

    Cooke, Chathan M.

    1979-01-01

    Electrically insulating gaseous media of unexpectedly high dielectric strength comprised of mixtures of two or more dielectric gases are disclosed wherein the dielectric strength of at least one gas in each mixture increases at less than a linear rate with increasing pressure and the mixture gases are present in such proportions that the sum of their electrical discharge voltages at their respective partial pressures exceeds the electrical discharge voltage of each individual gas at the same temperature and pressure as that of the mixture.

  13. Liquid Argon Dielectric Strength Measurements Sarah Lockwitz

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

    Argon Dielectric Strength Measurements Sarah Lockwitz Fermilab LArTPC R&D Workshop July, 9 2014 Fermilab LAr Dielectric Strength July 9, 2014 S. Lockwitz et al. Recent Interest in LAr High Voltage (HV) 2 Experiment Voltage ICARUS 75 kV Darkside 50 60 kV MicroBooNE 128 kV CAPTAIN 50 kV LBNE 170 kV GLACIER 1-2 MV LAr Dielectric Strength July 9, 2014 S. Lockwitz et al. Recent Interest in LAr High Voltage (HV) * Noble liquids are becoming a popular detector medium 2 Experiment Voltage ICARUS 75

  14. Heavy loads

    SciTech Connect (OSTI)

    Metz, D.

    1982-01-01

    The extreme pressures on the roof and walls of an earth-sheltered residential home are discussed and the need for careful planning is stressed. Pertinent terms are defined. Footings and wall structure (reinforced concrete walls and concrete block walls) are described. Roofing systems are discussed in detail and illustrated: (1) poured-in-place concrete roof slabs; (2) pre-cast concrete planks; and (3) heavy timber roofs. Insulation of earth-sheltered homes is reviewed in terms of using: (1) urethanes; (2) extruded polystyrene; and (3) expanded polystyrene. Advantages, disadvantages, R-factors, costs, and installation are discussed. (MJJ)

  15. Methods and apparatus for vertical coupling from dielectric waveguides

    DOE Patents [OSTI]

    Yaacobi, Ami; Cordova, Brad Gilbert

    2014-06-17

    A frequency-chirped nano-antenna provides efficient sub-wavelength vertical emission from a dielectric waveguide. In one example, this nano-antenna includes a set of plasmonic dipoles on the opposite side of a SiYV.sub.4 waveguide from a ground plane. The resulting structure, which is less than half a wavelength long, emits a broadband beam (e.g., >300 nm) that can be coupled into an optical fiber. In some embodiments, a diffractive optical element with unevenly shaped regions of high- and low-index dielectric material collimates the broadband beam for higher coupling efficiency. In some cases, a negative lens element between the nano-antenna and the diffractive optical element accelerates the emitted beam's divergence (and improves coupling efficiency), allowing for more compact packaging. Like the diffractive optical element, the negative lens element includes unevenly shaped regions of high- and low-index dielectric material that can be designed to compensate for aberrations in the beam emitted by the nano-antenna.

  16. Thermoluminescence and dielectric response of gamma irradiated muscovite mica

    SciTech Connect (OSTI)

    Kaur, Sukhnandan Singh, Surinder Singh, Lakhwant; Lochab, S. P.

    2014-04-24

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

  17. Thin film dielectric composite materials

    DOE Patents [OSTI]

    Jia, Quanxi; Gibbons, Brady J.; Findikoglu, Alp T.; Park, Bae Ho

    2002-01-01

    A dielectric composite material comprising at least two crystal phases of different components with TiO.sub.2 as a first component and a material selected from the group consisting of Ba.sub.1-x Sr.sub.x TiO.sub.3 where x is from 0.3 to 0.7, Pb.sub.1-x Ca.sub.x TiO.sub.3 where x is from 0.4 to 0.7, Sr.sub.1-x Pb.sub.x TiO.sub.3 where x is from 0.2 to 0.4, Ba.sub.1-x Cd.sub.x TiO.sub.3 where x is from 0.02 to 0.1, BaTi.sub.1-x Zr.sub.x O.sub.3 where x is from 0.2 to 0.3, BaTi.sub.1-x Sn.sub.x O.sub.3 where x is from 0.15 to 0.3, BaTi.sub.1-x Hf.sub.x O.sub.3 where x is from 0.24 to 0.3, Pb.sub.1-1.3x La.sub.x TiO.sub.3+0.2x where x is from 0.23 to 0.3, (BaTiO.sub.3).sub.x (PbFeo.sub.0.5 Nb.sub.0.5 O.sub.3).sub.1-x where x is from 0.75 to 0.9, (PbTiO.sub.3).sub.- (PbCo.sub.0.5 W.sub.0.5 O.sub.3).sub.1-x where x is from 0.1 to 0.45, (PbTiO.sub.3).sub.x (PbMg.sub.0.5 W.sub.0.5 O.sub.3).sub.1-x where x is from 0.2 to 0.4, and (PbTiO.sub.3).sub.x (PbFe.sub.0.5 Ta.sub.0.5 O.sub.3).sub.1-x where x is from 0 to 0.2, as the second component is described. The dielectric composite material can be formed as a thin film upon suitable substrates.

  18. Shot loading trainer analysis

    SciTech Connect (OSTI)

    Peterson, T.K.

    1995-02-15

    This document presents the results from the analysis of the shot loading trainer (SLT). This device will be used to test the procedure for installing shot into the annulus of the Project W-320 shipping container. To ensure that the shot is installed uniformly around the container, vibrators will be used to settle the shot. The SLT was analyzed to ensure that it would not jeopardize worker safety during operation. The results from the static analysis of the SLT under deadweight and vibrator operating loads show that the stresses in the SLT are below code allowables. The results from the modal analysis show that the natural frequencies of the SLT are far below the operating frequencies of the vibrators, provided the SLT is mounted on pneumatic tires. The SLT was also analyzed for wind, seismic, deadweight, and moving/transporting loads. Analysis of the SLT is in accordance with SDC-4.1 for safety class 3 structures (DOE-RL 1993) and the American Institute of Steel Construction (AISC) Manual of Steel Construction (AISC 1989).

  19. Dielectric silicone elastomers with mixed ceramic nanoparticles

    SciTech Connect (OSTI)

    Stiubianu, George; Bele, Adrian; Cazacu, Maria; Racles, Carmen; Vlad, Stelian; Ignat, Mircea

    2015-11-15

    Highlights: • Composite ceramics nanoparticles (MCN) with zirconium dioxide and lead zirconate. • Dielectric elastomer films wDith PDMS matrix and MCN as dielectric filler. • Hydrophobic character—water resistant and good flexibility specific to siloxanes. • Increased value of dielectric constant with the content of MCN in dielectric films. • Increased energy output from uniaxial deformation of the dielectric elastomer films. - Abstract: A ceramic material consisting in a zirconium dioxide-lead zirconate mixture has been obtained by precipitation method, its composition being proved by wide angle X-ray powder diffraction and energy-dispersive X-ray spectroscopy. The average diameter of the ceramic particles ranged between 50 and 100 nm, as revealed by transmission electron microscopy images. These were surface treated and used as filler for a high molecular mass polydimethylsiloxane-α,ω-diol (Mn = 450,000) prepared in laboratory, the resulted composites being further processed as films and crosslinked. A condensation procedure, unusual for polydimethylsiloxane having such high molecular mass, with a trifunctional silane was approached for the crosslinking. The effect of filler content on electrical and mechanical properties of the resulted materials was studied and it was found that the dielectric permittivity of nanocomposites increased in line with the concentration of ceramic nanoparticles.

  20. Dielectric investigations in nanostructured tetragonal BaTiO{sub 3} ceramics

    SciTech Connect (OSTI)

    Silveira, L.G.D.; Alves, M.F.S.; Ctica, L.F.; Gotardo, R.A.M.; Nascimento, W.J.; Garcia, D.; Eiras, J.A.; Santos, I.A.

    2013-05-15

    Highlights: ? Nanostructured BaTiO{sub 3} ceramics processed by an innovative protocol. ? Dielectric relaxations related to strains and vacancies. ? Dielectric and ferroelectric properties enhanced by strain. - Abstract: In this paper, structural and dielectric properties of BaTiO{sub 3} ceramics obtained under extreme conditions were investigated. The temperature dependent dielectric investigations revealed that the phase transition temperatures of the BaTiO{sub 3} ceramics were raised as a function of residual strains associated to the nanostructuration, while structural characterizations showed a tetragonal arrangement at room temperature. From the frequency dependence analyses of the imaginary parts of dielectric permittivity, impedance and modulus function, three relaxation processes were identified. Two of them exhibit activation energies of 0.45 and 0.63 eV, and were attributed to single and double-ionization of oxygen vacancies. The whole set of results also indicated that the electrons resulting from the ionization of oxygen vacancies are trapped and do not contribute to the electrical conductivity, while the physical properties of the analyzed samples were enhanced by retaining a strained microstructure.

  1. Structural and dielectric/ferroelectric properties of (La{sub 1-x}Nd{sub x}){sub 2}Ti{sub 2}O{sub 7} synthesized by sol-gel route

    SciTech Connect (OSTI)

    Shao Zhenmian; Saitzek, Sebastien; Roussel, Pascal; Mentre, Olivier; Prihor Gheorghiu, Felicia; Mitoseriu, Liliana; Desfeux, Rachel

    2010-07-15

    A series of compounds with the general formula (La{sub 1-x}Nd{sub x}){sub 2}Ti{sub 2}O{sub 7} (0.0{<=}x{<=}1.0) has been prepared by the sol-gel method. The decomposition of the gel was characterized by thermo-gravimetric analysis coupled to mass spectrometry, indicating the reaction is achieved above 850 {sup o}C. The lattice parameters versus x show an expected decrease in the a and b parameters while c and the {beta} angle remain almost unchanged with respect to the monoclinic symmetry conserved for the full solid solution. Dielectric, piezoelectric and ferroelectric properties were measured on the entire series. - Graphical abstract: XRD patterns of (La{sub 1-x}Nd{sub x}){sub 2}Ti{sub 2}O{sub 7} powders for various x values. The (hkl) peaks positions (with h and k{ne}0) change with x values while the (00l) peaks positions remain unaffected.

  2. Loading and conjugating cavity biostructures

    DOE Patents [OSTI]

    Hainfeld, J.F.

    1995-08-22

    Methods for the preparation and use of a biological delivery system are disclosed. The method of preparation includes the loading of a non-biological material into a biostructure having a load-bearing structure. The method also includes the removal of some of the biostructure`s contents and the loading of a non-biological material into the biostructure. The biostructure is biologically compatible with the host, and preferably is derived from the host, the host`s species or a related species. The loaded biostructure is used directly, or it can be targeted to specific cells, tissues and/or organs within a host. The targeted biostructure can be used to deliver the non-biological material to a specified tissue, organ or cell within a host for diagnostic, therapeutic or other purposes. 11 figs.

  3. Loading and conjugating cavity biostructures

    DOE Patents [OSTI]

    Hainfeld, J.F.

    1997-11-25

    Methods for the preparation and use of a biological delivery system are disclosed. The method of preparation includes the loading of a non-biological material into a biostructure having a load-bearing structure. The method also includes the removal of some of the biostructure`s contents and the loading of a non-biological material into the biostructure. The biostructure is biologically compatible with the host, and preferably is derived from the host, the host`s species or a related species. The loaded biostructure is used directly, or it can be targeted to specific cells, tissues and/or organs within a host. The targeted biostructure can be used to deliver the non-biological material to a specified tissue, organ or cell within a host for diagnostic, therapeutic or other purposes. 11 figs.

  4. Loading and conjugating cavity biostructures

    DOE Patents [OSTI]

    Hainfeld, James F.

    1997-11-25

    Methods for the preparation and use of a biological delivery system are disclosed. The method of preparation includes the loading of a non-biological material into a biostructure having a load-bearing structure. The method also includes the removal of some of the biostructure's contents and the loading of a non-biological material into the biostructure. The biostructure is biologically compatible with the host, and preferably is derived from the host, the host's species or a related species. The loaded biostructure is used directly, or it can be targeted to specific cells, tissues and/or organs within a host. The targeted biostructure can be used to deliver the non-biological material to a specified tissue, organ or cell within a host for diagnostic, therapeutic or other purposes.

  5. Loading and conjugating cavity biostructures

    DOE Patents [OSTI]

    Hainfeld, James F.

    1995-08-22

    Methods for the preparation and use of a biological delivery system are disclosed. The method of preparation includes the loading of a non-biological material into a biostructure having a load-bearing structure. The method also includes the removal of some of the biostructure's contents and the loading of a non-biological material into the biostructure. The biostructure is biologically compatible with the host, and preferably is derived from the host, the host's species or a related species. The loaded biostructure is used directly, or it can be targeted to specific cells, tissues and/or organs within a host. The targeted biostructure can be used to deliver the non-biological material to a specified tissue, organ or cell within a host for diagnostic, therapeutic or other purposes.

  6. III-V semiconductor nanoresonators-a new strategy for passive, active, and nonlinear all-dielectric metamaterials

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

    Liu, Sheng; Keeler, Gordon A.; Reno, John L.; Sinclair, Michael B.; Brener, Igal

    2016-06-10

    We demonstrate 2D and multilayer dielectric metamaterials made from III–V semiconductors using a monolithic fabrication process. The resulting structures could be used to recompress chirped femtosecond optical pulses and in a variety of other optical applications requiring low loss. Moreover, these III–V all-dielectric metamaterials could enable novel active applications such as efficient nonlinear frequency converters, light emitters, detectors, and modulators.

  7. Numerical modeling of multi-GeV laser wakefield electron acceleration inside a dielectric capillary tube

    SciTech Connect (OSTI)

    Paradkar, B. S.; Cros, B.; Maynard, G.; Mora, P.

    2013-08-15

    Numerical modeling of laser wakefield electron acceleration inside a gas filled dielectric capillary tube is presented. Guiding of a short pulse laser inside a dielectric capillary tube over a long distance (∼1 m) and acceleration of an externally injected electron bunch to ultra-relativistic energies (∼5-10 GeV) are demonstrated in the quasi-linear regime of laser wakefield acceleration. Two dimensional axisymmetric simulations were performed with the code WAKE-EP (Extended Performances), which allows computationally efficient simulations of such long scale plasma. The code is an upgrade of the quasi-static particle code, WAKE [P. Mora and T. M. Antonsen, Jr., Phys. Plasmas 4, 217 (1997)], to simulate the acceleration of an externally injected electron bunch (including beam loading effect) and propagation of the laser beam inside a dielectric capillary. The influence of the transverse electric field of the plasma wake on the radial loss of the accelerated electrons to the dielectric wall is investigated. The stable acceleration of electrons to multi-GeV energy with a non-resonant laser pulse with a large spot-size is demonstrated.

  8. Dielectric supported radio-frequency cavities

    DOE Patents [OSTI]

    Yu, David U. L.; Lee, Terry G.

    2000-01-01

    A device which improves the electrical and thermomechanical performance of an RF cavity, for example, in a disk-loaded accelerating structure. A washer made of polycrystalline diamond is brazed in the middle to a copper disk washer and at the outer edge to the plane wave transformer tank wall, thus dissipating heat from the copper disk to the outer tank wall while at the same time providing strong mechanical support to the metal disk. The washer structure eliminates the longitudinal connecting rods and cooling channels used in the currently available cavities, and as a result minimizes problems such as shunt impedance degradation and field distortion in the plane wave transformer, and mechanical deflection and uneven cooling of the disk assembly.

  9. Compact microwave lamp having a tuning block and a dielectric located in a lamp cavity

    DOE Patents [OSTI]

    Simpson, James E.

    2000-01-01

    A microwave lamp having a compact structure utilizing a coupling slot which has a dielectric member extending therethrough and a tuning block adjoining the coupling slot. A non-conventional waveguide is used which has about the width of a WR-284 waveguide and about the length of a WR-340 waveguide.

  10. Dielectric and magnetic investigations of GaFeO{sub 3} single crystals

    SciTech Connect (OSTI)

    Srimathy, B. Bhaumik, Indranil Ganesamoorthy, S. Karnal, A. K. Kumar, J.

    2014-04-24

    Structural, dielectric and magnetic properties have been investigated for the polar ferrimagnet, GaFeO{sub 3} single crystals grown by optical floating zone technique. Phase formation was confirmed from X-ray diffraction. Hopping conduction mechanism of Fe{sup 2+} ions and oxygen vacancies contribute to the electric polarization and dielectric constant of the material. Disorderness in the cation site gives rise to the magnetic ordering and the splitting in the zero field cooled (ZFC) and field cooled (FC) magnetization curves reveals the movement of the domain walls.

  11. Surface photoconductivity of organosilicate glass dielectrics induced by vacuum-ultraviolet radiation

    SciTech Connect (OSTI)

    Zheng, H.; Nichols, M. T.; Pei, D.; Shohet, J. L.; Nishi, Y.

    2013-08-14

    The temporary increase in the electrical surface conductivity of low-k organosilicate glass (SiCOH) during exposure to vacuum-ultraviolet radiation (VUV) is investigated. To measure the photoconductivity, patterned comb structures are deposited on dielectric films and exposed to synchrotron radiation in the range of 825 eV, which is in the energy range of most plasma vacuum-ultraviolet radiation. The change in photo surface conductivity induced by VUV radiation may be beneficial in limiting charging damage of dielectrics by depleting the plasma-deposited charge.

  12. A new method for achieving enhanced dielectric response over a wide temperature range

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

    Maurya, Deepam; Sun, Fu -Chang; Pamir Alpay, S.; Priya, Shashank

    2015-10-19

    We report a novel approach for achieving high dielectric response over a wide temperature range. In this approach, multilayer ceramic heterostructures with constituent compositions having strategically tuned Curie points (TC) were designed and integrated with varying electrical connectivity. Interestingly, these multilayer structures exhibited different dielectric behavior in series and parallel configuration due to variations in electrical boundary conditions resulting in the differences in the strength of the electrostatic coupling. The results are explained using nonlinear thermodynamic model taking into account electrostatic interlayer interaction. We believe that present work will have huge significance in design of high performance ceramic capacitors.

  13. High payload six-axis load sensor

    DOE Patents [OSTI]

    Jansen, John F.; Lind, Randall F.

    2003-01-01

    A repairable high-payload six-axis load sensor includes a table, a base, and at least three shear-pin load transducers removably mounted between the table and the base. Removable mounting permits easy replacement of damaged shear pins. Preferably, the shear-pin load transducers are responsive to shear forces imparted along the two axes perpendicular to an axis of minimum sensitivity characteristic of the transducer. Responsive to an applied shear force, each shear-pin load transducer can produce an electrical signal proportional to the reaction force. The load sensor can further include a structure for receiving the proportional electrical signals and computing the applied load corresponding to the proportional electrical signals. The computed load can be expressed in terms of a three-dimensional XYZ Cartesian coordinate system.

  14. Tuneable dielectric films having low electrical losses

    DOE Patents [OSTI]

    Dimos, Duane Brian; Schwartz, Robert William; Raymond, Mark Victor; Al-Shareef, Husam Niman; Mueller, Carl; Galt, David

    2000-01-01

    The present invention is directed to a method for forming dielectric thin films having substantially reduced electrical losses at microwave and millimeter wave frequencies relative to conventional dielectric thin films. The reduction in losses is realized by dramatically increasing the grain sizes of the dielectric films, thereby minimizing intergranular scattering of the microwave signal due to grain boundaries and point defects. The increase in grain size is realized by heating the film to a temperature at which the grains experience regrowth. The grain size of the films can be further increased by first depositing the films with an excess of one of the compoents, such that a highly mobile grain boundary phase is formed.

  15. Method of fabricating a solar cell with a tunnel dielectric layer

    SciTech Connect (OSTI)

    Dennis, Tim; Harrington, Scott; Manning, Jane; Smith, David D.; Waldhauer, Ann

    2015-08-18

    Method of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.

  16. Method of fabricating a solar cell with a tunnel dielectric layer

    DOE Patents [OSTI]

    Dennis, Tim; Harrington, Scott; Manning, Jane; Smith, David D; Waldhauer, Ann

    2014-04-29

    Methods of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.

  17. Method of fabricating a solar cell with a tunnel dielectric layer

    DOE Patents [OSTI]

    Dennis, Tim; Harrington, Scott; Manning, Jane; Smith, David; Waldhauer, Ann

    2012-12-18

    Methods of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.

  18. Method for fabrication of crack-free ceramic dielectric films

    DOE Patents [OSTI]

    Ma, Beihai; Narayanan, Manoj; Balachandran, Uthamalingam; Chao, Sheng; Liu, Shanshan

    2016-05-31

    The invention provides a process for forming crack-free dielectric films on a substrate. The process comprises the application of a dielectric precursor layer of a thickness from about 0.3 .mu.m to about 1.0 .mu.m to a substrate. The deposition is followed by low temperature heat pretreatment, prepyrolysis, pyrolysis and crystallization step for each layer. The deposition, heat pretreatment, prepyrolysis, pyrolysis and crystallization are repeated until the dielectric film forms an overall thickness of from about 1.5 .mu.m to about 20.0 .mu.m and providing a final crystallization treatment to form a thick dielectric film. The process provides a thick crack-free dielectric film on a substrate, the dielectric forming a dense thick crack-free dielectric having an overall dielectric thickness of from about 1.5 .mu.m to about 20.0 .mu.m.

  19. Method for fabrication of crack-free ceramic dielectric films

    DOE Patents [OSTI]

    Ma, Beihai; Balachandran, Uthamalingam; Chao, Sheng; Liu, Shanshan; Narayanan, Manoj

    2014-02-11

    The invention provides a process for forming crack-free dielectric films on a substrate. The process comprise the application of a dielectric precursor layer of a thickness from about 0.3 .mu.m to about 1.0 .mu.m to a substrate. The deposition is followed by low temperature heat pretreatment, prepyrolysis, pyrolysis and crystallization step for each layer. The deposition, heat pretreatment, prepyrolysis, pyrolysis and crystallization are repeated until the dielectric film forms an overall thickness of from about 1.5 .mu.m to about 20.0 .mu.m and providing a final crystallization treatment to form a thick dielectric film. Also provided was a thick crack-free dielectric film on a substrate, the dielectric forming a dense thick crack-free dielectric having an overall dielectric thickness of from about 1.5 .mu.m to about 20.0 .mu.m.

  20. Method for producing high dielectric strength microvalves

    DOE Patents [OSTI]

    Kirby, Brian J.; Reichmuth, David S.; Shepodd, Timothy J.

    2006-04-04

    A microvalve having a cast-in-place and lithographically shaped mobile, polymer monolith for fluid flow control in microfluidic devices and method of manufacture. The microvalve contains a porous fluorinated polymer monolithic element whose pores are filled with an electrically insulating, high dielectric strength fluid, typically a perfluorinated liquid. This combination provides a microvalve that combines high dielectric strength with extremely low electrical conductivity. These microvalves have been shown to have resistivities of at least 100 G.OMEGA. and are compatible with solvents such as water at a pH between 2.7 and 9.0, 1-1 propanol, acetonitrile, and acetone.

  1. STATUS OF THE DIELECTRIC WALL ACCELERATOR

    SciTech Connect (OSTI)

    Caporaso, G J; Chen, Y; Sampayan, S; Akana, G; Anaya, R; Blackfield, D; Carroll, J; Cook, E; Falabella, S; Guethlein, G; Harris, J; Hawkins, S; Hickman, B; Holmes, C; Horner, A; Nelson, S; Paul, A; Pearson, D; Poole, B; Richardson, R; Sanders, D; Selenes, K; Sullivan, J; Wang, L; Watson, J; Weir, J

    2009-04-22

    The dielectric wall accelerator (DWA) system being developed at the Lawrence Livermore National Laboratory (LLNL) uses fast switched high voltage transmission lines to generate pulsed electric fields on the inside of a high gradient insulating (HGI) acceleration tube. High electric field gradients are achieved by the use of alternating insulators and conductors and short pulse times. The system is capable of accelerating any charge to mass ratio particle. Applications of high gradient proton and electron versions of this accelerator will be discussed. The status of the developmental new technologies that make the compact system possible will be reviewed. These include, high gradient vacuum insulators, solid dielectric materials, photoconductive switches and compact proton sources.

  2. Dielectric Properties of Ice and Liquid Water from First Principles

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

    Calculations | Argonne Leadership Computing Facility Dielectric Properties of Ice and Liquid Water from First Principles Calculations Authors: Lu, D., Gygi, F., Galli, G. We present a first-principles study of the static dielectric properties of ice and liquid water. The eigenmodes of the dielectric matrix ϵ are analyzed in terms of maximally localized dielectric functions similar, in their definition, to maximally localized Wannier orbitals obtained from Bloch eigenstates of the electronic

  3. Material behavior under complex loading

    SciTech Connect (OSTI)

    Breuer, H.J.; Raule, G.; Rodig, M.

    1984-09-01

    Studies of material behavior under complex loading form a bridge between standard material testing methods and the stress analysis calculations for reactor components at high temperatures. The aim of these studies is to determine the influence of typical load change sequences on material properties, to derive the equations required for stress analyses, to carry out tests under multiaxial conditions, and to investigate the structural deformation mechanisms of creep buckling and ratcheting. The present state of the investigations within the high-temperature gas-cooled reactor materials program is described, with emphasis on the experimental apparatus, the scope of the program, and the initial results obtained.

  4. Norbornylene-based polymer systems for dielectric applications

    DOE Patents [OSTI]

    Dirk, Shawn M.; Wheeler, David R.

    2012-07-17

    A capacitor having at least one electrode pair being separated by a dielectric component, with the dielectric component being made of a polymer such as a norbornylene-containing polymer with a dielectric constant greater than 3 and a dissipation factor less than 0.1 where the capacitor has an operating temperature greater than 100.degree. C. and less than 170.degree. C.

  5. RF cavity using liquid dielectric for tuning and cooling

    DOE Patents [OSTI]

    Popovic, Milorad; Johnson, Rolland P.

    2012-04-17

    A system for accelerating particles includes an RF cavity that contains a ferrite core and a liquid dielectric. Characteristics of the ferrite core and the liquid dielectric, among other factors, determine the resonant frequency of the RF cavity. The liquid dielectric is circulated to cool the ferrite core during the operation of the system.

  6. Load sensing system

    DOE Patents [OSTI]

    Sohns, Carl W.; Nodine, Robert N.; Wallace, Steven Allen

    1999-01-01

    A load sensing system inexpensively monitors the weight and temperature of stored nuclear material for long periods of time in widely variable environments. The system can include an electrostatic load cell that encodes weight and temperature into a digital signal which is sent to a remote monitor via a coaxial cable. The same cable is used to supply the load cell with power. When multiple load cells are used, vast

  7. Damage free integration of ultralow-k dielectrics by template replacement approach

    SciTech Connect (OSTI)

    Zhang, L.; De Gendt, S.; Marneffe, J.-F. de; Heylen, N.; Murdoch, G.; Tokei, Z.; Boemmels, J.; Baklanov, M. R.

    2015-08-31

    Cu/low-k integration by conventional damascene approach is becoming increasingly difficult as critical dimensions scale down. An alternative integration scheme is studied based on the replacement of a sacrificial template by ultralow-k dielectric. A metal structure is first formed by patterning a template material. After template removal, a k = 2.31 spin-on type of porous low-k dielectric is deposited onto the patterned metal lines. The chemical and electrical properties of spin-on dielectrics are studied on blanket wafers, indicating that during hard bake, most porogen is removed within few minutes, but 120 min are required to achieve the lowest k-value. The effective dielectric constant of the gap-fill low-k is investigated on a 45 nm ½ pitch Meander-Fork structure, leading to k{sub eff} below 2.4. The proposed approach solves the two major challenges in conventional Cu/low-k damascene integration approach: low-k plasma damage and metal penetration during barrier deposition on porous materials.

  8. Thermal analysis and temperature dependent dielectric responses of Co doped anatase TiO{sub 2} nanoparticles

    SciTech Connect (OSTI)

    Alamgir; Khan, Wasi; Ahammed, Nashiruddin; Naqvi, A. H.; Ahmad, Shabbir

    2015-05-15

    Nanoparticles (NPs) of pure and 5?mol % cobalt doped TiO{sub 2} synthesized through acid modified sol-gel method were characterized to understand their thermal, structural, morphological, and temperature dependent dielectric properties. Thermogravimetric analysis (TGA) has been used for thermal studies and indicates the weight loss in two steps due to the removal of residual organics. X-ray diffraction study was employed to confirm the formation of single anatase phase with tetragonal symmetry for both pure and 5?mol % Co doped TiO{sub 2} NPs. The average crystallite size of both samples was calculated from the Scherrers formula and was found in the range from 9-11?nm. TEM micrographs of these NPs reflect their shape and distribution. The dielectric constant (??), dielectric loss (tan?) and ac conductivity (?{sub ac}) were also studied as a function of temperature at different frequencies. Electrical responses of the synthesized NPs have been analyzed carefully in the framework of relevant models. It is also noticed that the dielectric constant (??) of the samples found to decrease with increasing frequency but increases with increasing temperature up to a particular value and then sharply decreases. Temperature variation of dielectric constant exhibits step like escalation and shows relaxation behavior. Study of dielectric properties shows dominant dependence on the grain size as well as Co ion incorporation in TiO{sub 2}.

  9. Load Model Data Tool

    SciTech Connect (OSTI)

    David Chassin, Pavel Etingov

    2013-04-30

    The LMDT software automates the process of the load composite model data preparation in the format supported by the major power system software vendors (GE and Siemens). Proper representation of the load composite model in power system dynamic analysis is very important. Software tools for power system simulation like GE PSLF and Siemens PSSE already include algorithms for the load composite modeling. However, these tools require that the input information on composite load to be provided in custom formats. Preparation of this data is time consuming and requires multiple manual operations. The LMDT software enables to automate this process. Software is designed to generate composite load model data. It uses the default load composition data, motor information, and bus information as an input. Software processes the input information and produces load composition model. Generated model can be stored in .dyd format supported by GE PSLF package or .dyr format supported by Siemens PSSE package.

  10. Load Model Data Tool

    Energy Science and Technology Software Center (OSTI)

    2013-04-30

    The LMDT software automates the process of the load composite model data preparation in the format supported by the major power system software vendors (GE and Siemens). Proper representation of the load composite model in power system dynamic analysis is very important. Software tools for power system simulation like GE PSLF and Siemens PSSE already include algorithms for the load composite modeling. However, these tools require that the input information on composite load to bemore » provided in custom formats. Preparation of this data is time consuming and requires multiple manual operations. The LMDT software enables to automate this process. Software is designed to generate composite load model data. It uses the default load composition data, motor information, and bus information as an input. Software processes the input information and produces load composition model. Generated model can be stored in .dyd format supported by GE PSLF package or .dyr format supported by Siemens PSSE package.« less

  11. Changes in the dielectric properties of medaka fish embryos during development, studied by electrorotation

    SciTech Connect (OSTI)

    Shirakashi, Ryo; Mischke, Miriam; Fischer, Peter; Memmel, Simon; Krohne, Georg; Fuhr, Guenter R.; Zimmermann, Heiko; Sukhorukov, Vladimir L.

    2012-11-09

    Highlights: Black-Right-Pointing-Pointer Electrorotation offers a non-invasive tool for dielectric analysis of fish embryos. Black-Right-Pointing-Pointer The three-shell dielectric model matches the rotation spectra of medaka eggs. Black-Right-Pointing-Pointer The capacitance value suggests a double-membrane structure of yolk envelope. -- Abstract: The Japanese medaka fish, Oryzias latipes, has become a powerful vertebrate model organism in developmental biology and genetics. The present study explores the dielectric properties of medaka embryos during pre-hatching development by means of the electrorotation (ROT) technique. Due to their layered structure, medaka eggs exhibited up to three ROT peaks in the kHz-MHz frequency range. During development from blastula to early somite stage, ROT spectra varied only slightly. But as the embryo progressed to the late-somite stage, the ROT peaks underwent significant changes in frequency and amplitude. Using morphological data obtained by light and electron microscopy, we analyzed the ROT spectra with a three-shell dielectric model that accounted for the major embryonic compartments. The analysis yielded a very high value for the ionic conductivity of the egg shell (chorion), which was confirmed by independent osmotic experiments. A relatively low capacitance of the yolk envelope was consistent with its double-membrane structure revealed by transmission electron microscopy. Yolk-free dead eggs exhibited only one co-field ROT peak, shifted markedly to lower frequencies with respect to the corresponding peak of live embryos. The dielectric data may be useful for monitoring the development and changes in fish embryos' viability/conditions in basic research and industrial aquaculture.

  12. Investigation on dielectric properties of atomic layer deposited Al{sub 2}O{sub 3} dielectric films

    SciTech Connect (OSTI)

    Y?ld?z, Dilber Esra; Y?ld?r?m, Mert; Gken, Muharrem

    2014-05-15

    Al/Al{sub 2}O{sub 3}/p-Si Schottky barrier diodes (SBDs) were fabricated using atomic layer deposition technique in order to investigate dielectric properties of SBDs. For this purpose, admittance measurements were conducted at room temperature between ?1?V and 3?V in the frequency range of 10 kHz and 1?MHz. In addition to the investigation of Al{sub 2}O{sub 3} morphology using atomic force microscope, dielectric parameters; such as dielectric constant (??), dielectric loss (??), dielectric loss tangent (tan??), and real and imaginary parts of dielectric modulus (M? and M?, respectively), were calculated and effect of frequency on these parameters of Al/Al{sub 2}O{sub 3}/p-Si SBDs was discussed. Variations in these parameters at low frequencies were associated with the effect of interface states in low frequency region. Besides dielectric parameters, ac electrical conductivity of these SBDs was also investigated.

  13. Photo-induced change of dielectric response in BaCoSiO{sub 4} stuffed tridymite

    SciTech Connect (OSTI)

    Taniguchi, Hiroki Okamura, Takuma; Yamamoto, Takafumi; Okazaki, Ryuji; Terasaki, Ichiro; Moriwake, Hiroki; Kuwabara, Akihide; Itoh, Mitsuru

    2014-04-28

    The photodielectric effect is demonstrated in Mott-insulator BaCoSiO{sub 4} with a stuffed-tridymite-type structure under irradiation of visible light at 365?nm. The real part of dielectric permittivity is enhanced by ?300% with little increase of tan?? in a low-frequency region. Results of diffuse reflectance spectroscopy, first-principles calculations and dielectric measurements suggest that the photodielectric effect stems from a response of photo-excited electrons in an unoccupied upper-Hubbard band for 3d-orbitals of cobalt, which have significantly small mobility due to the unique configuration of Co ions in the stuffed-tridymite-type structure.

  14. Load Leveling Battery System Costs

    Energy Science and Technology Software Center (OSTI)

    1994-10-12

    SYSPLAN evaluates capital investment in customer side of the meter load leveling battery systems. Such systems reduce the customer's monthly electrical demand charge by reducing the maximum power load supplied by the utility during the customer's peak demand. System equipment consists of a large array of batteries, a current converter, and balance of plant equipment and facilities required to support the battery and converter system. The system is installed on the customer's side of themore » meter and controlled and operated by the customer. Its economic feasibility depends largely on the customer's load profile. Load shape requirements, utility rate structures, and battery equipment cost and performance data serve as bases for determining whether a load leveling battery system is economically feasible for a particular installation. Life-cycle costs for system hardware include all costs associated with the purchase, installation, and operation of battery, converter, and balance of plant facilities and equipment. The SYSPLAN spreadsheet software is specifically designed to evaluate these costs and the reduced demand charge benefits; it completes a 20 year period life cycle cost analysis based on the battery system description and cost data. A built-in sensitivity analysis routine is also included for key battery cost parameters. The life cycle cost analysis spreadsheet is augmented by a system sizing routine to help users identify load leveling system size requirements for their facilities. The optional XSIZE system sizing spreadsheet which is included can be used to identify a range of battery system sizes that might be economically attractive. XSIZE output consisting of system operating requirements can then be passed by the temporary file SIZE to the main SYSPLAN spreadsheet.« less

  15. Enhanced dielectric-wall linear accelerator

    DOE Patents [OSTI]

    Sampayan, Stephen E.; Caporaso, George J.; Kirbie, Hugh C.

    1998-01-01

    A dielectric-wall linear accelerator is enhanced by a high-voltage, fast e-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.

  16. Enhanced dielectric-wall linear accelerator

    DOE Patents [OSTI]

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

    1998-09-22

    A dielectric-wall linear accelerator is enhanced by a high-voltage, fast e-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. 6 figs.

  17. Nondestructive millimeter wave imaging and spectroscopy using dielectric focusing probes

    SciTech Connect (OSTI)

    Hejase, Jose A.; Shane, Steven S.; Park, Kyoung Y.; Chahal, Premjeet

    2014-02-18

    A tool for interrogating objects over a wide band of frequencies with subwavelength resolution at small standoff distances (near field region) in the transmission mode using a single source and detector measurement setup in the millimeter wave band is presented. The design utilizes optics like principles for guiding electromagnetic millimeter waves from large cross-sectional areas to considerably smaller sub-wavelength areas. While plano-convex lenses can be used to focus waves to a fine resolution, they usually require a large stand-off distance thus resulting in alignment and spacing issues. The design procedure and simulation analysis of the focusing probes are presented in this study along with experimental verification of performance and imaging and spectroscopy examples. Nondestructive evaluation will find benefit from such an apparatus including biological tissue imaging, electronic package integrity testing, composite dielectric structure evaluation for defects and microfluidic sensing.

  18. Load sensing system

    DOE Patents [OSTI]

    Sohns, C.W.; Nodine, R.N.; Wallace, S.A.

    1999-05-04

    A load sensing system inexpensively monitors the weight and temperature of stored nuclear material for long periods of time in widely variable environments. The system can include an electrostatic load cell that encodes weight and temperature into a digital signal which is sent to a remote monitor via a coaxial cable. The same cable is used to supply the load cell with power. When multiple load cells are used, vast inventories of stored nuclear material can be continuously monitored and inventoried of minimal cost. 4 figs.

  19. Load regulating expansion fixture

    DOE Patents [OSTI]

    Wagner, L.M.; Strum, M.J.

    1998-12-15

    A free standing self contained device for bonding ultra thin metallic films, such as 0.001 inch beryllium foils is disclosed. The device will regulate to a predetermined load for solid state bonding when heated to a bonding temperature. The device includes a load regulating feature, whereby the expansion stresses generated for bonding are regulated and self adjusting. The load regulator comprises a pair of friction isolators with a plurality of annealed copper members located therebetween. The device, with the load regulator, will adjust to and maintain a stress level needed to successfully and economically complete a leak tight bond without damaging thin foils or other delicate components. 1 fig.

  20. Load regulating expansion fixture

    DOE Patents [OSTI]

    Wagner, Lawrence M.; Strum, Michael J.

    1998-01-01

    A free standing self contained device for bonding ultra thin metallic films, such as 0.001 inch beryllium foils. The device will regulate to a predetermined load for solid state bonding when heated to a bonding temperature. The device includes a load regulating feature, whereby the expansion stresses generated for bonding are regulated and self adjusting. The load regulator comprises a pair of friction isolators with a plurality of annealed copper members located therebetween. The device, with the load regulator, will adjust to and maintain a stress level needed to successfully and economically complete a leak tight bond without damaging thin foils or other delicate components.

  1. Solution processed lanthanum aluminate gate dielectrics for use in metal oxide-based thin film transistors

    SciTech Connect (OSTI)

    Esro, M.; Adamopoulos, G.; Mazzocco, R.; Kolosov, O.; Krier, A.; Vourlias, G.; Milne, W. I.

    2015-05-18

    We report on ZnO-based thin-film transistors (TFTs) employing lanthanum aluminate gate dielectrics (La{sub x}Al{sub 1−x}O{sub y}) grown by spray pyrolysis in ambient atmosphere at 440 °C. The structural, electronic, optical, morphological, and electrical properties of the La{sub x}Al{sub 1−x}O{sub y} films and devices as a function of the lanthanum to aluminium atomic ratio were investigated using a wide range of characterization techniques such as UV-visible absorption spectroscopy, impedance spectroscopy, spectroscopic ellipsometry, atomic force microscopy, x-ray diffraction, and field-effect measurements. As-deposited LaAlO{sub y} dielectrics exhibit a wide band gap (∼6.18 eV), high dielectric constant (k ∼ 16), low roughness (∼1.9 nm), and very low leakage currents (<3 nA/cm{sup 2}). TFTs employing solution processed LaAlO{sub y} gate dielectrics and ZnO semiconducting channels exhibit excellent electron transport characteristics with hysteresis-free operation, low operation voltages (∼10 V), high on/off current modulation ratio of >10{sup 6}, subthreshold swing of ∼650 mV dec{sup −1}, and electron mobility of ∼12 cm{sup 2} V{sup −1} s{sup −1}.

  2. Plasmas, Dielectrics and the Ultrafast: First Science and Operational...

    Office of Scientific and Technical Information (OSTI)

    Ultrafast: First Science and Operational Experience at FACET Citation Details In-Document Search Title: Plasmas, Dielectrics and the Ultrafast: First Science and Operational ...

  3. Fabricating Dielectric Ceramic Films on Copper Foils | Argonne...

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

    Fabricating Dielectric Ceramic Films on Copper Foils Technology available for licensing: A method for coating a ceramic film on copper foil. Process creates higher performing and ...

  4. Resonant dielectric metamaterials (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    The resonant dielectric metamaterials are low-loss 3D isotropic materials with negative permittivity and permeability. Such isotropic double negative materials offer polarization ...

  5. A Dielectric Relaxometry Study of Segmental Dynamics in PDMS...

    Office of Scientific and Technical Information (OSTI)

    in PDMSBoron Composite and Hybrid Elastomers Citation Details In-Document Search Title: A Dielectric Relaxometry Study of Segmental Dynamics in PDMSBoron Composite and ...

  6. Two-Phase Liquid Dielectric - Energy Innovation Portal

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

    Return to Search Two-Phase Liquid Dielectric Lawrence Livermore National Laboratory ... Lawrence Livermore National Laboratory researchers have developed a two-phase liquid ...

  7. Machine learning strategy for accelerated design of polymer dielectric...

    Office of Scientific and Technical Information (OSTI)

    Machine learning strategy for accelerated design of polymer dielectrics Citation Details In-Document Search Title: Machine learning strategy for accelerated design of polymer ...

  8. Viscoelastic effects on frequency tuning of a dielectric elastomer membrane resonator

    SciTech Connect (OSTI)

    Zhou, Jianyou; Jiang, Liying Khayat, Roger E.

    2014-03-28

    As a recent application of dielectric elastomers (DEs), DE resonators have become an alternative to conventional silicon-based resonators used in MEMS and have attracted much interest from the research community. However, most existing modeling works for the DE resonators ignore the intrinsic viscoelastic effect of the material that may strongly influence their dynamic performance. Based on the finite-deformation viscoelasticity theory for dielectrics, this paper theoretically examines the in-plane oscillation of a DE membrane resonator to demonstrate how the material viscoelasticity affects the actuation and frequency tuning processes of the resonator. From the simulation results, it is concluded that not only the applied voltage can change the natural frequency of the resonator, but also the inelastic deformation contributes to frequency tuning. Due to the viscoelasticity of the material, the electrical loading rate influences the actuation process of the DE resonator, while it has little effect on the final steady frequency tuned by the prescribed voltage within the safety range. With the consideration of the typical failure modes of the resonator and the evolution process of the material, the tunable frequency range and the safe range of the applied voltage of the DE membrane resonator with different dimension parameters are determined in this work, which are found to be dependent on the electrical loading rate. This work is expected to provide a better understanding on the frequency tuning of viscoelastic DE membrane resonators and a guideline for the design of DE devices.

  9. Superconducting structure

    DOE Patents [OSTI]

    Kwon, Chuhee; Jia, Quanxi; Foltyn, Stephen R.

    2003-04-01

    A superconductive structure including a dielectric oxide substrate, a thin buffer layer of a superconducting material thereon; and, a layer of a rare earth-barium-copper oxide superconducting film thereon the thin layer of yttrium-barium-copper oxide, the rare earth selected from the group consisting of samarium, gadolinium, ytterbium, erbium, neodymium, dysprosium, holmium, lutetium, a combination of more than one element from the rare earth group and a combination of one or more elements from the rare earth group with yttrium, the buffer layer of superconducting material characterized as having chemical and structural compatibility with the dielectric oxide substrate and the rare earth-barium-copper oxide superconducting film is provided.

  10. Superconducting Structure

    DOE Patents [OSTI]

    Kwon, Chuhee; Jia, Quanxi; Foltyn, Stephen R.

    2005-09-13

    A superconductive structure including a dielectric oxide substrate, a thin buffer layer of a superconducting material thereon; and, a layer of a rare earth-barium-copper oxide superconducting film thereon the thin layer of yttrium-barium-copper oxide, the rare earth selected from the group consisting of samarium, gadolinium, ytterbium, erbium, neodymium, dysprosium, holmium, lutetium, a combination of more than one element from the rare earth group and a combination of one or more elements from the rare earth group with yttrium, the buffer layer of superconducting material characterized as having chemical and structural compatibility with the dielectric oxide substrate and the rare earth-barium-copper oxide superconducting film is provided.

  11. Sequential lateral solidification of silicon thin films on low-k dielectrics for low temperature integration

    SciTech Connect (OSTI)

    Carta, Fabio Hlaing, Htay; Kymissis, Ioannis; Gates, Stephen M.; Edelstein, Daniel C.; Limanov, Alexander B.; Im, James S.

    2014-12-15

    We present the excimer laser crystallization of amorphous silicon on a low dielectric constant (low-k) insulator for very large scale integration monolithic 3D integration and demonstrate that low dielectric constant materials are suitable substrates for 3D integration through laser crystallization of silicon thin films. We crystallized 100 nm amorphous silicon on top of SiO{sub 2} and SiCOH (low-k) dielectrics, at different material thicknesses (1 μm, 0.75 μm, and 0.5 μm). The amorphous silicon crystallization on low-k dielectric requires 35% less laser energy than on an SiO{sub 2} dielectric. This difference is related to the thermal conductivity of the two materials, in agreement with one dimensional simulations of the crystallization process. We analyzed the morphology of the material through defect-enhanced microscopy, Raman spectroscopy, and X-ray diffraction analysis. SEM micrographs show that polycrystalline silicon is characterized by micron-long grains with an average width of 543 nm for the SiO{sub 2} sample and 570 nm for the low-k samples. Comparison of the Raman spectra does not show any major difference in film quality for the two different dielectrics, and polycrystalline silicon peaks are closely placed around 517 cm{sup −1}. From X-ray diffraction analysis, the material crystallized on SiO{sub 2} shows a preferential (111) crystal orientation. In the SiCOH case, the 111 peak strength decreases dramatically and samples do not show preferential crystal orientation. A 1D finite element method simulation of the crystallization process on a back end of line structure shows that copper (Cu) damascene interconnects reach a temperature of 70 °C or lower with a 0.5 μm dielectric layer between the Cu and the molten Si layer, a favorable condition for monolithic 3D integration.

  12. Detecting Partial Energy Modulation in a Dielectric Laser Accelerator - Oral Presentation

    SciTech Connect (OSTI)

    Lukaczyk, Louis

    2015-08-24

    The Dielectric Laser Acceleration group at SLAC uses micro-fabricated dielectric grating structures and conventional infrared lasers to accelerator electrons. These structures have been estimated to produce an accelerating gradient up to 2 orders of magnitude greater than that produced by conventional RF accelerators. The success of the experiment depends on both the laser damage threshold of the structure and the timing overlap of femtosecond duration laser pulses with the electron bunch. In recent dielectric laser acceleration experiments, the laser pulse was shorter both temporally and spatially than the electron bunch. As a result, the laser is theorized to have interacted with only a small portion of the electron bunch. The detection of this phenomenon, referred to as partial population modulation, required a new approach to the data analysis of the electron energy spectra. A fitting function was designed to separate the accelerated electron population from the unaccelerated electron population. The approach was unsuccessful in detecting acceleration in the partial population modulation data. However, the fitting functions provide an excellent figure of merit for previous data known to contain signatures of acceleration.

  13. Load Balancing Scientific Applications

    SciTech Connect (OSTI)

    Pearce, Olga Tkachyshyn

    2014-12-01

    The largest supercomputers have millions of independent processors, and concurrency levels are rapidly increasing. For ideal efficiency, developers of the simulations that run on these machines must ensure that computational work is evenly balanced among processors. Assigning work evenly is challenging because many large modern parallel codes simulate behavior of physical systems that evolve over time, and their workloads change over time. Furthermore, the cost of imbalanced load increases with scale because most large-scale scientific simulations today use a Single Program Multiple Data (SPMD) parallel programming model, and an increasing number of processors will wait for the slowest one at the synchronization points. To address load imbalance, many large-scale parallel applications use dynamic load balance algorithms to redistribute work evenly. The research objective of this dissertation is to develop methods to decide when and how to load balance the application, and to balance it effectively and affordably. We measure and evaluate the computational load of the application, and develop strategies to decide when and how to correct the imbalance. Depending on the simulation, a fast, local load balance algorithm may be suitable, or a more sophisticated and expensive algorithm may be required. We developed a model for comparison of load balance algorithms for a specific state of the simulation that enables the selection of a balancing algorithm that will minimize overall runtime.

  14. Modeling of dielectric elastomer as electromechanical resonator

    SciTech Connect (OSTI)

    Li, Bo Liu, Lei; Chen, Hualing; Jia, Shuhai; Zhang, Junshi; Li, Dichen

    2014-09-28

    Dielectric elastomers (DEs) feature nonlinear dynamics resulting from an electromechanical coupling. Under alternating voltage, the DE resonates with tunable performances. We present an analysis of the nonlinear dynamics of a DE as electromechanical resonator (DEER) configured as a pure shear actuator. A theoretical model is developed to characterize the complex performance under different boundary conditions. Physical mechanisms are presented and discussed. Chaotic behavior is also predicted, illustrating instabilities in the dynamics. The results provide a guide to the design and application of DEER in haptic devices.

  15. Experimental demonstration of superdirective dielectric antenna

    SciTech Connect (OSTI)

    Krasnok, Alexander E.; Filonov, Dmitry S.; Belov, Pavel A.; Simovski, Constantin R.; Kivshar, Yuri S.

    2014-03-31

    We propose and demonstrate experimentally a simple approach for achieving superdirectivity of emitted radiation for electrically small antennas based on a spherical dielectric resonator with a notch excited by a dipole source. Superdirectivity is achieved without using complex antenna arrays and for a wide range of frequencies. We also demonstrate the steering effect for a subwavelength displacement of the source. Finally, unlike previously known superdirective antennas, our design has significantly smaller losses, at the operation frequency radiation efficiency attains 80%, and matching holds in the 3%-wide frequency band without any special matching technique.

  16. A loaded thermoacoustic engine

    SciTech Connect (OSTI)

    Olson, J.R.; Swift, G.W.

    1995-11-01

    Measurements and analysis of the performance of a thermoacoustic engine driving a dissipative load are presented. The effect of the load can be explained qualitatively using a simple low-amplitude approximation and quantitatively by invoking a more accurate low-amplitude numerical solution. The heater power {ital @};DQ and hot-end temperature {ital T}{sub {ital H}} are found to be simple functions of the load impedance and the unloaded values of {ital @};DQ and {ital T}{sub {ital H}}. {copyright} {ital 1995} {ital Acoustical} {ital Society} {ital of} {ital America}.

  17. From Organized High-Throughput Data to Phenomenological Theory using Machine Learning: The Example of Dielectric Breakdown

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

    Kim, Chiho; Pilania, Ghanshyam; Ramprasad, Ramamurthy

    2016-02-02

    Understanding the behavior (and failure) of dielectric insulators experiencing extreme electric fields is critical to the operation of present and emerging electrical and electronic devices. Despite its importance, the development of a predictive theory of dielectric breakdown has remained a challenge, owing to the complex multiscale nature of this process. We focus on the intrinsic dielectric breakdown field of insulators—the theoretical limit of breakdown determined purely by the chemistry of the material, i.e., the elements the material is composed of, the atomic-level structure, and the bonding. Starting from a benchmark dataset (generated from laborious first principles computations) of the intrinsicmore » dielectric breakdown field of a variety of model insulators, simple predictive phenomenological models of dielectric breakdown are distilled using advanced statistical or machine learning schemes, revealing key correlations and analytical relationships between the breakdown field and easily accessible material properties. Lastly, the models are shown to be general, and can hence guide the screening and systematic identification of high electric field tolerant materials.« less

  18. Method of fabricating conductive electrodes on the front and backside of a thin film structure

    DOE Patents [OSTI]

    Tabada, Phillipe J.; Tabada, legal representative, Melody; Pannu, Satinderpall S.

    2011-05-22

    A method of fabricating a thin film device having conductive front and backside electrodes or contacts. Top-side cavities are first formed on a first dielectric layer, followed by the deposition of a metal layer on the first dielectric layer to fill the cavities. Defined metal structures are etched from the metal layer to include the cavity-filled metal, followed by depositing a second dielectric layer over the metal structures. Additional levels of defined metal structures may be formed in a similar manner with vias connecting metal structures between levels. After a final dielectric layer is deposited, a top surface of a metal structure of an uppermost metal layer is exposed through the final dielectric layer to form a front-side electrode, and a bottom surface of a cavity-filled portion of a metal structure of a lowermost metal layer is also exposed through the first dielectric layer to form a back-side electrode.

  19. IT and Building Loads

    SciTech Connect (OSTI)

    Hastbacka, Mildred; Rutberg, Michael; Bouza, Antonio

    2013-09-30

    The article discusses available technologies for reducing IT energy consumption and the commensurate cooling load in commercial buildings. This article addresses the energy savings and market potential of these strategies as well.

  20. LOADING MACHINE FOR REACTORS

    DOE Patents [OSTI]

    Simon, S.L.

    1959-07-01

    An apparatus is described for loading or charging slugs of fissionable material into a nuclear reactor. The apparatus of the invention is a "muzzle loading" type comprising a delivery tube or muzzle designed to be brought into alignment with any one of a plurality of fuel channels. The delivery tube is located within the pressure shell and it is also disposed within shielding barriers while the fuel cantridges or slugs are forced through the delivery tube by an externally driven flexible ram.

  1. Load research manual. Volume 3. Load research for advanced technologies

    SciTech Connect (OSTI)

    Brandenburg, L.; Clarkson, G.; Grund, Jr., C.; Leo, J.; Asbury, J.; Brandon-Brown, F.; Derderian, H.; Mueller, R.; Swaroop, R.

    1980-11-01

    This three-volume manual presents technical guidelines for electric utility load research. Special attention is given to issues raised by the load data reporting requirements of the Public Utility Regulatory Policies Act of 1978 and to problems faced by smaller utilities that are initiating load research programs. The manual includes guides to load research literature and glossaries of load research and statistical terms. In Volume 3, special load research procedures are presented for solar, wind, and cogeneration technologies.

  2. Method of manufacturing flexible metallic photonic band gap structures, and structures resulting therefrom

    DOE Patents [OSTI]

    Gupta, Sandhya; Tuttle, Gary L.; Sigalas, Mihail; McCalmont, Jonathan S.; Ho, Kai-Ming

    2001-08-14

    A method of manufacturing a flexible metallic photonic band gap structure operable in the infrared region, comprises the steps of spinning on a first layer of dielectric on a GaAs substrate, imidizing this first layer of dielectric, forming a first metal pattern on this first layer of dielectric, spinning on and imidizing a second layer of dielectric, and then removing the GaAs substrate. This method results in a flexible metallic photonic band gap structure operable with various filter characteristics in the infrared region. This method may be used to construct multi-layer flexible metallic photonic band gap structures. Metal grid defects and dielectric separation layer thicknesses are adjusted to control filter parameters.

  3. Nanostructure multilayer dielectric materials for capacitors and insulators

    DOE Patents [OSTI]

    Barbee, T.W. Jr.; Johnson, G.W.

    1998-04-21

    A capacitor is formed of at least two metal conductors having a multilayer dielectric and opposite dielectric-conductor interface layers in between. The multilayer dielectric includes many alternating layers of amorphous zirconium oxide (ZrO{sub 2}) and alumina (Al{sub 2}O{sub 3}). The dielectric-conductor interface layers are engineered for increased voltage breakdown and extended service life. The local interfacial work function is increased to reduce charge injection and thus increase breakdown voltage. Proper material choices can prevent electrochemical reactions and diffusion between the conductor and dielectric. Physical vapor deposition is used to deposit the zirconium oxide (ZrO{sub 2}) and alumina (Al{sub 2}O{sub 3}) in alternating layers to form a nano-laminate. 1 fig.

  4. Nanostructure multilayer dielectric materials for capacitors and insulators

    DOE Patents [OSTI]

    Barbee, Jr., Troy W.; Johnson, Gary W.

    1998-04-21

    A capacitor is formed of at least two metal conductors having a multilayer dielectric and opposite dielectric-conductor interface layers in between. The multilayer dielectric includes many alternating layers of amorphous zirconium oxide (ZrO.sub.2) and alumina (Al.sub.2 O.sub.3). The dielectric-conductor interface layers are engineered for increased voltage breakdown and extended service life. The local interfacial work function is increased to reduce charge injection and thus increase breakdown voltage. Proper material choices can prevent electrochemical reactions and diffusion between the conductor and dielectric. Physical vapor deposition is used to deposit the zirconium oxide (ZrO.sub.2) and alumina (Al.sub.2 O.sub.3) in alternating layers to form a nano-laminate.

  5. Load Monitoring CEC/LMTF Load Research Program

    SciTech Connect (OSTI)

    Huang, Zhenyu; Lesieutre, B.; Yang, Steve; Ellis, A.; Meklin, A.; Wong, B.; Gaikwad, A.; Brooks, D.; Hammerstrom, Donald J.; Phillips, John; Kosterev, Dmitry; Hoffman, M.; Ciniglio, O.; Hartwell, R.; Pourbeik, P.; Maitra, A.; Lu, Ning

    2007-11-30

    This white paper addresses the needs, options, current practices of load monitoring. Recommendations on load monitoring applications and future directions are also presented.

  6. High loading uranium fuel plate

    DOE Patents [OSTI]

    Wiencek, Thomas C.; Domagala, Robert F.; Thresh, Henry R.

    1990-01-01

    Two embodiments of a high uranium fuel plate are disclosed which contain a meat comprising structured uranium compound confined between a pair of diffusion bonded ductile metal cladding plates uniformly covering the meat, the meat having a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel plates are fabricated by a hot isostatic pressing process.

  7. Integration of nonlinear dielectric barium strontium titanate with polycrystalline yttrium iron garnet

    SciTech Connect (OSTI)

    Jia, Q.X.; Groves, J.R.; Arendt, P.; Fan, Y.; Findikoglu, A.T.; Foltyn, S.R.; Jiang, H.; Miranda, F.A.

    1999-03-01

    Biaxially oriented nonlinear dielectric Ba{sub 0.6}Sr{sub 0.4}TiO{sub 3} (BST) films have been grown on polycrystalline ferrite yttrium iron garnet (YIG) substrates. We use a structurally and chemically compatible MgO buffer to improve the crystallinity of the BST on polycrystalline YIG substrates, where the biaxially oriented MgO is deposited by an ion-beam assisted-deposition technique. The biaxially oriented BST has a dielectric loss of less than 0.01 and a capacitance tunability of greater than 25{percent} at a direct current bias voltage of 40 V at room temperature. {copyright} {ital 1999 American Institute of Physics.}

  8. Numerical simulation of torus breakdown to chaos in an atmospheric-pressure dielectric barrier discharge

    SciTech Connect (OSTI)

    Zhang, J.; Wang, Y. H.; Wang, D. Z. [Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-08-15

    Understanding the routes to chaos occurring in atmospheric-pressure dielectric barrier discharge systems by changing controlling parameters is very important to predict and control the dynamical behaviors. In this paper, a route of a quasiperiodic torus to chaos via the strange nonchaotic attractor is observed in an atmospheric-pressure dielectric barrier discharge driven by triangle-wave voltage. By increasing the driving frequency, the discharge system first bifurcates to a quasiperiodic torus from a stable single periodic state, and then torus and phase-locking periodic state appear and disappear alternately. In the meantime, the torus becomes increasingly wrinkling and stretching, and gradually approaches a fractal structure with the nonpositive largest Lyapunov exponent, i.e., a strange nonchaotic attractor. After that, the discharge system enters into chaotic state. If the driving frequency is further increased, another well known route of period-doubling bifurcation to chaos is also observed.

  9. Electric and magnetic response in dielectric dark states for low loss subwavelength optical meta atoms

    SciTech Connect (OSTI)

    Jain, Aditya; Moitra, Parikshit; Koschny, Thomas; Valentine, Jason; Soukoulis, Costas M.

    2015-07-14

    Artificially created surfaces or metasurfaces, composed of appropriately shaped subwavelength structures, namely, meta-atoms, control light at subwavelength scales. Historically, metasurfaces have used radiating metallic resonators as subwavelength inclusions. However, while resonant optical metasurfaces made from metal have been sufficiently subwavelength in the propagation direction, they are too lossy for many applications. Metasurfaces made out of radiating dielectric resonators have been proposed to solve the loss problem, but are marginally subwavelength at optical frequencies. We designed subwavelength resonators made out of nonradiating dielectrics. The resonators are decorated with appropriately placed scatterers, resulting in a meta-atom with an engineered electromagnetic response. A metasurface that yields an electric response is fabricated, experimentally characterized, and a method to obtain a magnetic response at optical frequencies is theoretically demonstrated. In conclusion, this design methodology paves the way for metasurfaces that are simultaneously subwavelength and low loss.

  10. Characterization of vertical strain silicon MOSFET incorporating dielectric pocket (SDP-VMOSFET)

    SciTech Connect (OSTI)

    Napiah, Z. A. F. M. E-mail: nazirah6969@gmail.com E-mail: idzdihar@utem.edu.my E-mail: yashidar@yahoo.com Makhtar, N. E-mail: nazirah6969@gmail.com E-mail: idzdihar@utem.edu.my E-mail: yashidar@yahoo.com Othman, M. A. E-mail: nazirah6969@gmail.com E-mail: idzdihar@utem.edu.my E-mail: yashidar@yahoo.com Idris, M. I. E-mail: nazirah6969@gmail.com E-mail: idzdihar@utem.edu.my E-mail: yashidar@yahoo.com Arith, F. E-mail: nazirah6969@gmail.com E-mail: idzdihar@utem.edu.my E-mail: yashidar@yahoo.com Yasin, N. Y. M. E-mail: nazirah6969@gmail.com E-mail: idzdihar@utem.edu.my E-mail: yashidar@yahoo.com Taib, S. N. E-mail: nazirah6969@gmail.com E-mail: idzdihar@utem.edu.my E-mail: yashidar@yahoo.com

    2014-02-24

    The vertical Metal-Oxide-Semiconductor Field-Effect-Transistor (MOSFET) leads to a double channel width that can increase the packaging density. The strained silicon MOSFET was introduced to modify the carrier transport properties of silicon in order to enhance transport of both electrons and holes within strained layer. Dielectric pocket was act to control encroachment of the drain doping into the channel and reduce short channel effects (SCE). SDP-VMOSFET which was a combination of those advantages was proposed to overcome the SCE in term of leakage current, threshold voltage roll-off also Drain Induce Barrier Lowering (DIBL). As a result, SDP-VMOSFET produces a better threshold voltage and DIBL compared to related structures. Meanwhile, it gives slightly increased for leakage current compared to Vertical MOSFET Incorporating Dielectric Pocket. The characteristics of the SDP-VMOSFET are analyzed in order to optimize the performance of the device and leading to the next generation of IC technology.

  11. Electric and magnetic response in dielectric dark states for low loss subwavelength optical meta atoms

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

    Jain, Aditya; Moitra, Parikshit; Koschny, Thomas; Valentine, Jason; Soukoulis, Costas M.

    2015-07-14

    Artificially created surfaces or metasurfaces, composed of appropriately shaped subwavelength structures, namely, meta-atoms, control light at subwavelength scales. Historically, metasurfaces have used radiating metallic resonators as subwavelength inclusions. However, while resonant optical metasurfaces made from metal have been sufficiently subwavelength in the propagation direction, they are too lossy for many applications. Metasurfaces made out of radiating dielectric resonators have been proposed to solve the loss problem, but are marginally subwavelength at optical frequencies. We designed subwavelength resonators made out of nonradiating dielectrics. The resonators are decorated with appropriately placed scatterers, resulting in a meta-atom with an engineered electromagnetic response. Amore » metasurface that yields an electric response is fabricated, experimentally characterized, and a method to obtain a magnetic response at optical frequencies is theoretically demonstrated. In conclusion, this design methodology paves the way for metasurfaces that are simultaneously subwavelength and low loss.« less

  12. Sandia Wind Turbine Loads Database

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

    Wind Turbine Loads Database - Sandia Energy Energy Search Icon Sandia Home Locations ... Twitter Google + Vimeo Newsletter Signup SlideShare Sandia Wind Turbine Loads Database ...

  13. Computational evaluation of the flexoelectric effect in dielectric solids

    SciTech Connect (OSTI)

    Abdollahi, Amir; Peco, Christian; Milln, Daniel; Arroyo, Marino; Arias, Irene

    2014-09-07

    Flexoelectricity is a size-dependent electromechanical mechanism coupling polarization and strain gradient. It exists in a wide variety of materials, and is most noticeable for nanoscale objects, where strain gradients are higher. Simulations are important to understand flexoelectricity because experiments at very small scales are difficult, and analytical solutions are scarce. Here, we computationally evaluate the role of flexoelectricity in the electromechanical response of linear dielectric solids in two-dimensions. We deal with the higher-order coupled partial differential equations using smooth meshfree basis functions in a Galerkin method, which allows us to consider general geometries and boundary conditions. We focus on the most common setups to quantify the flexoelectric response, namely, bending of cantilever beams and compression of truncated pyramids, which are generally interpreted through approximate solutions. While these approximations capture the size-dependent flexoelectric electromechanical coupling, we show that they only provide order-of-magnitude estimates as compared with a solution fully accounting for the multidimensional nature of the problem. We discuss the flexoelectric mechanism behind the enhanced size-dependent elasticity in beam configurations. We show that this mechanism is also responsible for the actuation of beams under purely electrical loading, supporting the idea that a mechanical flexoelectric sensor also behaves as an actuator. The predicted actuation-induced curvature is in a good agreement with experimental results. The truncated pyramid configuration highlights the critical role of geometry and boundary conditions on the effective electromechanical response. Our results suggest that computer simulations can help understanding and quantifying the physical properties of flexoelectric devices.

  14. A comparison of measured wind park load histories with the WISPER and WISPERX load spectra

    SciTech Connect (OSTI)

    Kelley, N.D.

    1995-01-01

    The blade-loading histories from two adjacent Micon 65/13 wind turbines are compared with the variable-amplitude test-loading histories known as the WISPER and WISPERX spectra. These standardized loading sequences were developed from blade flapwise load histories taken from nine different horizontal-axis wind turbines operating under a wide range of conditions in Europe. The subject turbines covered a broad spectrum of rotor diameters, materials, and operating environments. The final loading sequences were developed as a joint effort of thirteen different European organizations. The goal was to develop a meaningful loading standard for horizontal-axis wind turbine blades that represents common interaction effects seen in service. In 1990, NREL made extensive load measurements on two adjacent Micon 65/13 wind turbines in simultaneous operation in the very turbulent environment of a large wind park. Further, before and during the collection of the loads data, comprehensive measurements of the statistics of the turbulent environment were obtained at both the turbines under test and at two other locations within the park. The trend to larger but lighter wind turbine structures has made an understanding of the expected lifetime loading history of paramount importance. Experience in the US has shown that the turbulence-induced loads associated with multi-row wind parks in general are much more severe than for turbines operating individually or within widely spaced environments. Multi-row wind parks are much more common in the US than in Europe. In this paper we report on our results in applying the methodology utilized to develop the WISPER and WISPERX standardized loading sequences using the available data from the Micon turbines. While the intended purpose of the WISPER sequences were not to represent a specific operating environment, we believe the exercise is useful, especially when a turbine design is likely to be installed in a multi-row wind park.

  15. Multidimensional spectral load balancing

    DOE Patents [OSTI]

    Hendrickson, Bruce A.; Leland, Robert W.

    1996-12-24

    A method of and apparatus for graph partitioning involving the use of a plurality of eigenvectors of the Laplacian matrix of the graph of the problem for which load balancing is desired. The invention is particularly useful for optimizing parallel computer processing of a problem and for minimizing total pathway lengths of integrated circuits in the design stage.

  16. LOADING AND UNLOADING DEVICE

    DOE Patents [OSTI]

    Treshow, M.

    1960-08-16

    A device for loading and unloading fuel rods into and from a reactor tank through an access hole includes parallel links carrying a gripper. These links enable the gripper to go through the access hole and then to be moved laterally from the axis of the access hole to the various locations of the fuel rods in the reactor tank.

  17. Nonlinear dielectric thin films for active and electrically tunable microwave devices

    SciTech Connect (OSTI)

    Findikoglu, A.T.; Jia, Q.X.; Reagor, D.W.; Wu, X.D.

    1996-11-01

    The authors have prepared electrically tunable and active microwave devices incorporating (superconducting YBa{sub 2}Cu{sub 3}O{sub 7{minus}x})/(nonlinear dielectric SrTiO{sub 3}) or (normal metal Au)/(nonlinear dielectric Sr{sub 0.5}Ba{sub 0.5}TiO{sub 3}) bilayers. The dielectric layer thickness for these samples varied between 0.5 {micro}m and 2 {micro}m. The top electrode layer for each sample was patterned into a coplanar waveguide device structure. The authors have configures these devices as voltage-tunable resonators, voltage-tunable phase shifters, voltage-tunable mixers, and voltage-tunable filters. Under dc voltage bias, these prototype devices have exhibited up to 30% resonant frequency modulation, about 1{degree}/mm-GHz phase shift, more than 40 dB change in mixed microwave power, and fine-tunable symmetric filter profile with less than 2% bandwidth and more than 15% adaptive range.

  18. Subwavelength silicon through-hole arrays as an all-dielectric broadband terahertz gradient index metamaterial

    SciTech Connect (OSTI)

    Park, Sang-Gil; Jeong, Ki-Hun; Lee, Kanghee; Han, Daehoon; Ahn, Jaewook

    2014-09-01

    Structuring at subwavelength scales brings out artificial media with anomalous optical features called metamaterials. All-dielectric metamaterials have high potential for practical applications over the whole electromagnetic spectrum owing to low loss and optical isotropy. Here, we report subwavelength silicon through-hole arrays as an all-dielectric gradient index metamaterial with broadband THz operation. The unit cell consists of a single subwavelength through-hole on highly resistive monocrystalline silicon. Depending on the fill-factor and period, the effective index was linearly modulated at 0.3–1.6 THz. The experimental results also demonstrate silicon gradient refractive index (Si-GRIN) lenses with parabolic index profiles through the spatial modification of a single unit cell along the radial direction. Si-GRIN lenses either focus 0.4–1.6 THz beam to the diffraction-limit or serve as a flat and thin solid immersion lens on the backside of THz photoconductive antenna for highly efficient pulse extraction. This all-dielectric gradient index metamaterial opens up opportunities for integrated THz GRIN optics.

  19. Measuring alignment of loading fixture

    DOE Patents [OSTI]

    Scavone, Donald W. (Saratoga Springs, NY)

    1989-01-01

    An apparatus and method for measuring the alignment of a clevis and pin type loading fixture for compact tension specimens include a pair of substantially identical flat loading ligaments. Each loading ligament has two apertures for the reception of a respective pin of the loading fixture and a thickness less than one-half of a width of the clevis opening. The pair of loading ligaments are mounted in the clevis openings at respective sides thereof. The loading ligaments are then loaded by the pins of the loading fixture and the strain in each loading ligament is measured. By comparing the relative strain of each loading ligament, the alignment of the loading fixture is determined. Preferably, a suitable strain gage device is located at each longitudinal edge of a respective loading ligament equidistant from the two apertures in order to determine the strain thereat and hence the strain of each ligament. The loading ligaments are made substantially identical by jig grinding the loading ligaments as a matched set. Each loading ligament can also be individually calibrated prior to the measurement.

  20. High thermal conductivity lossy dielectric using co-densified multilayer configuration

    DOE Patents [OSTI]

    Tiegs, Terry N.; Kiggans, Jr., James O.

    2003-06-17

    Systems and methods are described for loss dielectrics. A method of manufacturing a lossy dielectric includes providing at least one high dielectric loss layer and providing at least one high thermal conductivity-electrically insulating layer adjacent the at least one high dielectric loss layer and then densifying together. The systems and methods provide advantages because the lossy dielectrics are less costly and more environmentally friendly than the available alternatives.

  1. Researchers measure how specific atoms move in dielectric materials...

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

    how atoms move in dielectric materials in order to store that charge," says Tedi-Marie Usher, a Ph.D. candidate in materials science and engineering at NC State and lead...

  2. Measurement of the optical dielectric function of monolayertransition...

    Office of Scientific and Technical Information (OSTI)

    Measurement of the optical dielectric function of monolayer transition-metal dichalcogenides:MoS2,MoSe2,WS2, andWSe2 This content will become publicly available on November 17,...

  3. Switchable and non-switchable zero backscattering of dielectric...

    Office of Scientific and Technical Information (OSTI)

    Title: Switchable and non-switchable zero backscattering of dielectric nano-resonators Authors: Wang, Feng ; Wei, Qi-Huo ; Htoon, Han Publication Date: 2015-02-27 OSTI Identifier: ...

  4. Local representation of the electronic dielectric response function

    SciTech Connect (OSTI)

    Lu, Deyu; Ge, Xiaochuan

    2015-12-11

    We present a local representation of the electronic dielectric response function, based on a spatial partition of the dielectric response into contributions from each occupied Wannier orbital using a generalized density functional perturbation theory. This procedure is fully ab initio, and therefore allows us to rigorously define local metrics, such as “bond polarizability,” on Wannier centers. We show that the locality of the bare response function is determined by the locality of three quantities: Wannier functions of the occupied manifold, the density matrix, and the Hamiltonian matrix. Furthermore, in systems with a gap, the bare dielectric response is exponentially localized, which supports the physical picture of the dielectric response function as a collection of interacting local responses that can be captured by a tight-binding model.

  5. Local representation of the electronic dielectric response function

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

    Lu, Deyu; Ge, Xiaochuan

    2015-12-11

    We present a local representation of the electronic dielectric response function, based on a spatial partition of the dielectric response into contributions from each occupied Wannier orbital using a generalized density functional perturbation theory. This procedure is fully ab initio, and therefore allows us to rigorously define local metrics, such as “bond polarizability,” on Wannier centers. We show that the locality of the bare response function is determined by the locality of three quantities: Wannier functions of the occupied manifold, the density matrix, and the Hamiltonian matrix. Furthermore, in systems with a gap, the bare dielectric response is exponentially localized,more » which supports the physical picture of the dielectric response function as a collection of interacting local responses that can be captured by a tight-binding model.« less

  6. Cube-corner reflectors with interference dielectric coating

    SciTech Connect (OSTI)

    Sokolov, A L; Murashkin, V V; Akent'ev, A S; Karaseva, E A

    2013-09-30

    The cube-corner reflectors (CCRs) with a special interference dielectric coating intended for ring retroreflector systems of space vehicles with uniaxial orientation are considered. The diffraction patterns of radiation reflected from the CCRs with different face coatings are studied. It is shown that the choice of the angle between the faces, the size and the coating of CCR faces allow essential variation in the diffraction pattern, thereby providing its optimisation for solving different navigation problems. (nanogradient dielectric coatings and metamaterials)

  7. Plasmas, Dielectrics and the Ultrafast: First Science and Operational

    Office of Scientific and Technical Information (OSTI)

    Experience at FACET (Conference) | SciTech Connect Conference: Plasmas, Dielectrics and the Ultrafast: First Science and Operational Experience at FACET Citation Details In-Document Search Title: Plasmas, Dielectrics and the Ultrafast: First Science and Operational Experience at FACET FACET (Facility for Advanced Accelerator and Experimental Tests) is an accelerator R&D test facility that has been recently constructed at SLAC National Accelerator Laboratory. The facility provides 20 GeV,

  8. Encapsulation methods and dielectric layers for organic electrical devices

    DOE Patents [OSTI]

    Blum, Yigal D; Chu, William Siu-Keung; MacQueen, David Brent; Shi, Yijan

    2013-07-02

    The disclosure provides methods and materials suitable for use as encapsulation barriers and dielectric layers in electronic devices. In one embodiment, for example, there is provided an electroluminescent device or other electronic device with a dielectric layer comprising alternating layers of a silicon-containing bonding material and a ceramic material. The methods provide, for example, electronic devices with increased stability and shelf-life. The invention is useful, for example, in the field of microelectronic devices.

  9. LDRD final report : mesoscale modeling of dynamic loading of heterogeneous

    Office of Scientific and Technical Information (OSTI)

    materials. (Technical Report) | SciTech Connect LDRD final report : mesoscale modeling of dynamic loading of heterogeneous materials. Citation Details In-Document Search Title: LDRD final report : mesoscale modeling of dynamic loading of heterogeneous materials. Material response to dynamic loading is often dominated by microstructure (grain structure, porosity, inclusions, defects). An example critically important to Sandia's mission is dynamic strength of polycrystalline metals where

  10. Controlling guided modes in plasmonic metal/dielectric multilayer waveguides

    SciTech Connect (OSTI)

    Wickremasinghe, N.; Wang, X.; Wagner, H. P.; Thompson, J.; Schmitzer, H.

    2015-06-07

    We investigate the mode properties of planar dielectric aluminum-quinoline (Alq{sub 3}) multilayer waveguides comprising one single or three equally spaced embedded nanometer-thin (∼10 nm thick) Alq{sub 3}-Mg{sub 0.9}:Ag{sub 0.1} composite metal-island layers. The plasmonic waveguides were fabricated by organic molecular beam deposition. Transverse magnetic (TM) and transverse electric (TE) modes were selectively excited using the m-line method. The symmetric plasmonic TM{sub 0} mode was launched in all waveguides and—in addition—two higher order plasmonic TM{sub 1} and TM{sub 2} modes were generated in waveguides comprising three metal layers. Other TM modes have hybrid dielectric-plasmonic characters, showing an increased effective refractive index when one electric field antinode is close to a metallic layer. TM modes which have all their antinode(s) in the dielectric layers propagate essentially like dielectric modes. TE modes with antinode(s) at the position of the metal layer(s) are strongly damped while the losses are low for TE modes comprising a node at the position of the composite metal film(s). The possibility to control the effective refractive index and the losses for individual hybrid plasmonic-dielectric TM and dielectric TE modes opens new design opportunities for mode selective waveguides and TM-TE mode couplers.

  11. Silica aerogel: An intrinsically low dielectric constant material

    SciTech Connect (OSTI)

    Hrubesh, L.W.

    1995-04-01

    Silica aerogels are highly porous solids having unique morphologies in wavelength of visible which both the pores and particles have sizes less than the wavelength of visible light. This fine nanostructure modifies the normal transport mechanisms within aerogels and endows them with a variety of exceptional physical properties. For example, aerogels have the lowest measured thermal conductivity and dielectric constant for any solid material. The intrinsically low dielectric properties of silica aerogels are the direct result of the extremely high achievable porosities, which are controllable over a range from 75% to more than 99.8 %, and which result in measured dielectric constants from 2.0 to less than 1.01. This paper discusses the synthesis of silica aerogels, processing them as thin films, and characterizing their dielectric properties. Existing data and other physical characteristics of bulk aerogels (e.g., thermal stablity, thermal expansion, moisture adsorption, modulus, dielectric strength, etc.), which are useful for evaluating them as potential dielectrics for microelectronics, are also given.

  12. Load responsive hydrodynamic bearing

    DOE Patents [OSTI]

    Kalsi, Manmohan S.; Somogyi, Dezso; Dietle, Lannie L.

    2002-01-01

    A load responsive hydrodynamic bearing is provided in the form of a thrust bearing or journal bearing for supporting, guiding and lubricating a relatively rotatable member to minimize wear thereof responsive to relative rotation under severe load. In the space between spaced relatively rotatable members and in the presence of a liquid or grease lubricant, one or more continuous ring shaped integral generally circular bearing bodies each define at least one dynamic surface and a plurality of support regions. Each of the support regions defines a static surface which is oriented in generally opposed relation with the dynamic surface for contact with one of the relatively rotatable members. A plurality of flexing regions are defined by the generally circular body of the bearing and are integral with and located between adjacent support regions. Each of the flexing regions has a first beam-like element being connected by an integral flexible hinge with one of the support regions and a second beam-like element having an integral flexible hinge connection with an adjacent support region. A least one local weakening geometry of the flexing region is located intermediate the first and second beam-like elements. In response to application of load from one of the relatively rotatable elements to the bearing, the beam-like elements and the local weakening geometry become flexed, causing the dynamic surface to deform and establish a hydrodynamic geometry for wedging lubricant into the dynamic interface.

  13. Electrical Load Modeling and Simulation

    SciTech Connect (OSTI)

    Chassin, David P.

    2013-01-01

    Electricity consumer demand response and load control are playing an increasingly important role in the development of a smart grid. Smart grid load management technologies such as Grid FriendlyTM controls and real-time pricing are making their way into the conventional model of grid planning and operations. However, the behavior of load both affects, and is affected by load control strategies that are designed to support electric grid planning and operations. This chapter discussed the natural behavior of electric loads, how it interacts with various load control and demand response strategies, what the consequences are for new grid operation concepts and the computing issues these new technologies raise.

  14. Semimetallization of dielectrics in strong optical fields

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

    Kwon, Ojoon; Paasch-Colberg, Tim; Apalkov, Vadym; Kim, Bum -Kyu; Kim, Ju -Jin; Stockman, Mark I.; Kim, D.

    2016-02-18

    At the heart of ever growing demands for faster signal processing is ultrafast charge transport and control by electromagnetic fields in semiconductors. Intense optical fields have opened fascinating avenues for new phenomena and applications in solids. Because the period of optical fields is on the order of a femtosecond, the current switching and its control by an optical field may pave a way to petahertz optoelectronic devices. Lately, a reversible semimetallization in fused silica on a femtosecond time scale by using a few-cycle strong field (~1 V/Å) is manifested. The strong Wannier-Stark localization and Zener-type tunneling were expected to drivemore » this ultrafast semimetallization. Wider spread of this technology demands better understanding of whether the strong field behavior is universally similar for different dielectrics. Here we employ a carrier-envelope-phase stabilized, few-cycle strong optical field to drive the semimetallization in sapphire, calcium fluoride and quartz and to compare this phenomenon and show its remarkable similarity between them. The similarity in response of these materials, despite the distinguishable differences in their physical properties, suggests the universality of the physical picture explained by the localization of Wannier-Stark states. Lastly, our results may blaze a trail to PHz-rate optoelectronics.« less

  15. Integration of atomic layer deposited high-k dielectrics on GaSb via hydrogen plasma exposure

    SciTech Connect (OSTI)

    Ruppalt, Laura B. Cleveland, Erin R.; Champlain, James G.; Bennett, Brian R.; Prokes, Sharka M.

    2014-12-15

    In this letter we report the efficacy of a hydrogen plasma pretreatment for integrating atomic layer deposited (ALD) high-k dielectric stacks with device-quality p-type GaSb(001) epitaxial layers. Molecular beam eptiaxy-grown GaSb surfaces were subjected to a 30 minute H{sub 2}/Ar plasma treatment and subsequently removed to air. High-k HfO{sub 2} and Al{sub 2}O{sub 3}/HfO{sub 2} bilayer insulating films were then deposited via ALD and samples were processed into standard metal-oxide-semiconductor (MOS) capacitors. The quality of the semiconductor/dielectric interface was probed by current-voltage and variable-frequency admittance measurements. Measurement results indicate that the H{sub 2}-plamsa pretreatment leads to a low density of interface states nearly independent of the deposited dielectric material, suggesting that pre-deposition H{sub 2}-plasma exposure, coupled with ALD of high-k dielectrics, may provide an effective means for achieving high-quality GaSb MOS structures for advanced Sb-based digital and analog electronics.

  16. commercial load | OpenEI Community

    Open Energy Info (EERE)

    data load data load profile OpenEI residential load TMY3 United States Load data Image source: NREL Files: applicationzip icon System Advisor Model Tool for Downloading Load Data...

  17. residential load | OpenEI Community

    Open Energy Info (EERE)

    data load data load profile OpenEI residential load TMY3 United States Load data Image source: NREL Files: applicationzip icon System Advisor Model Tool for Downloading Load Data...

  18. load profile | OpenEI Community

    Open Energy Info (EERE)

    data load data load profile OpenEI residential load TMY3 United States Load data Image source: NREL Files: applicationzip icon System Advisor Model Tool for Downloading Load Data...

  19. Embedded high-contrast distributed grating structures

    DOE Patents [OSTI]

    Zubrzycki, Walter J.; Vawter, Gregory A.; Allerman, Andrew A.

    2002-01-01

    A new class of fabrication methods for embedded distributed grating structures is claimed, together with optical devices which include such structures. These new methods are the only known approach to making defect-free high-dielectric contrast grating structures, which are smaller and more efficient than are conventional grating structures.

  20. Multidimensional spectral load balancing

    SciTech Connect (OSTI)

    Hendrickson, B.; Leland, R.

    1993-01-01

    We describe an algorithm for the static load balancing of scientific computations that generalizes and improves upon spectral bisection. Through a novel use of multiple eigenvectors, our new spectral algorithm can divide a computation into 4 or 8 pieces at once. These multidimensional spectral partitioning algorithms generate balanced partitions that have lower communication overhead and are less expensive to compute than those produced by spectral bisection. In addition, they automatically work to minimize message contention on a hypercube or mesh architecture. These spectral partitions are further improved by a multidimensional generalization of the Kernighan-Lin graph partitioning algorithm. Results on several computational grids are given and compared with other popular methods.

  1. Variable loading roller

    DOE Patents [OSTI]

    Williams, Daniel M.

    1989-01-01

    An automatic loading roller for transmitting torque in traction drive devices in manipulator arm joints includes a two-part camming device having a first cam portion rotatable in place on a shaft by an input torque and a second cam portion coaxially rotatable and translatable having a rotating drive surface thereon for engaging the driven surface of an output roller with a resultant force proportional to the torque transmitted. Complementary helical grooves on the respective cam portions interconnected through ball bearings interacting with those grooves effect the rotation and translation of the second cam portion in response to rotation of the first.

  2. Variable loading roller

    DOE Patents [OSTI]

    Williams, D.M.

    1988-01-21

    An automatic loading roller for transmitting torque in traction drive devices in manipulator arm joints includes a two-part camming device having a first cam portion rotatable in place on a shaft by an input torque and a second cam portion coaxially rotatable and translatable having a rotating drive surface thereon for engaging the driven surface of an output roller with a resultant force proportional to the torque transmitted. Complementary helical grooves in the respective cam portions interconnected through ball bearings interacting with those grooves effect the rotation and translation of the second cam portion in response to rotation of the first. 14 figs.

  3. Plug Loads Conservation Measures

    Energy Science and Technology Software Center (OSTI)

    2010-12-31

    This software requires inputs of simple plug loads inventory information and calculates the energy and cost benefits of various retrofit opportunities. This tool includes energy conservation measures for: Vending Machine Misers, Delamp Vending Machine, Desktop to Laptop retrofit, CRT to LCD monitors retrofit, Computer Power Management Settings, and Energy Star Refrigerator retrofit. This tool calculates energy savings, demand reduction, cost savings, building life cycle costs including: simple payback, discounted payback, net-present value, and savings tomore » investment ratio. In addition this tool also displays the environmental benefits of a project.« less

  4. Effect of mechanical alloying synthesis process on the dielectric properties of (Bi{sub 0.5}Na{sub 0.5}){sub 0.94}Ba{sub 0.06}TiO{sub 3} piezoceramics

    SciTech Connect (OSTI)

    Ghazanfari, Mohammad Reza; Amini, Rasool; Shams, Seyyedeh Fatemeh; Alizadeh, Morteza; Ardakani, Hamed Ahmadi

    2015-08-15

    Highlights: • MA samples show higher dielectric permittivity and Curie temperature. • In MA samples, dielectric loss is almost 27% less than conventional ones. • In MA samples, sintering time and temperature are lower than conventional ones. • In MA samples, particle morphology is more homogeneous conventional ones. • In MA samples, crystallite size is smaller conventional ones. - Abstract: In present work, in order to study the effects of synthesis techniques on dielectric properties, the BNBT lead-free piezoceramics with (Bi{sub 0.5}Na{sub 0.5}){sub 0.94}Ba{sub 0.06}TiO{sub 3} stoichiometry (called as BNBT6) were synthesized by mechanical alloying (MA) and conventional mixed oxides methods. The structural, microstructural, and dielectric properties were carried out by X-ray diffractometer (XRD), scanning electron microscope (SEM), and impedance analyzer LCR meter, respectively. Based on results, the density of MA samples is considerably higher than conventional samples owning to smaller particles size and more uniformity of particle shape of MA samples. Moreover, the dielectric properties of MA samples are comparatively improved in which the dielectric loss of these samples is almost 27% less than conventional ones. Furthermore, MA samples exhibit obviously higher dielectric permittivity and Curie temperature compared to the conventional samples.

  5. Dielectric characteristic of photoinduced isomerization in azo-dye doped polymeric matrices

    SciTech Connect (OSTI)

    Luo Duanbin; Deng Li

    2006-05-01

    The dielectric permittivities and losses of poly(methyl methacrylate) doped with different concentrations of azo dye are investigated under the irradiation of 532 nm light for the first time. The dielectric permittivities increase with the concentration of chromophores increasing, and the dielectric relaxation is mainly influenced by the doped azo-dye chromophores. Given the dye concentration, the dielectric permittivities depend on the pump power of 532 nm light. With the increase of pumping light power, the low frequency dielectric losses increase while the high frequency dielectric losses decrease. The results are explained based on the photoinduced isomerization of chromophores and the interaction between the chromophores and polymer matrices.

  6. Load Control System Reliability

    SciTech Connect (OSTI)

    Trudnowski, Daniel

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  7. The influence of carbon doping on the performance of Gd{sub 2}O{sub 3} as high-k gate dielectric

    SciTech Connect (OSTI)

    Shekhter, P.; Yehezkel, S.; Shriki, A.; Eizenberg, M.; Chaudhuri, A. R.; Osten, H. J.; Laha, A.

    2014-12-29

    One of the approaches for overcoming the issue of leakage current in modern metal-oxide-semiconductor devices is utilizing the high dielectric constants of lanthanide based oxides. We investigated the effect of carbon doping directly into Gd{sub 2}O{sub 3} layers on the performance of such devices. It was found that the amount of carbon introduced into the dielectric is above the solubility limit; carbon atoms enrich the oxide-semiconductor interface and cause a significant shift in the flat band voltage of the stack. Although the carbon atoms slightly degrade this interface, this method has a potential for tuning the flat band voltage of such structures.

  8. Millimeter-Wave Dielectric Properties of Single Crystal Ferroelectric and Dielectric Materials

    SciTech Connect (OSTI)

    McCloy, John S.; Korolev, Konstantin A.; Li, Zijing; Afsar, Mohammed N.; Sundaram, S. K.

    2011-01-03

    Transmittance measurements on various single crystal ferroelectric materials over a broad millimeter-wave frequency range have been performed. Frequency dependence of the complex dielectric permittivity has been determined in the millimeter wave region for the first time. The measurements have been employed using a free-space quasi-optical millimeter-wave spectrometer equipped with a set of high power backward wave oscillators (BWOs) as sources of coherent radiation, tunable in the range from 30 - 120 GHz. The uncertainties and possible sources of instrumentation and measurement errors related to the free-space millimeter-wave technique are discussed. This work has demonstrated that precise MMW permittivities can be obtained even on small thin crystals using the BWO quasi-optical approach.

  9. Numerical simulation of electron energy loss near inhomogeneous dielectrics

    SciTech Connect (OSTI)

    Garcia de Abajo, F.J.

    1997-12-01

    The nonrelativistic energy loss suffered by fast electrons passing near dielectric interfaces of arbitrary shape is calculated by solving Poisson{close_quote}s equation using the boundary-charge method. The potential induced by a moving electron is expressed in terms of surface-charge distributions placed at the interfaces. These surface charges, obtained by self-consistently solving the resulting integral equation, act back on the electron producing a retarding force and hence energy loss. The dielectrics are described by frequency-dependent dielectric functions. Two particular cases are discussed in further detail: interfaces invariant under translation along one particular direction and axially symmetric interfaces. Previous results for simple geometries, such as planes, spheres, and cylinders, based upon analytical solutions, are fully reproduced within this approach. Calculations are presented for electrons moving near wedges, coupled parallel cylinders, coupled spheres, and toroidal surfaces. {copyright} {ital 1997} {ital The American Physical Society}

  10. Quantitative nanometer-scale mapping of dielectric tunability

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

    Tselev, Alexander; Klein, Andreas; Gassmann, Juergen; Jesse, Stephen; Li, Qian; Kalinin, Sergei V.; Wisinger, Nina Balke

    2015-08-21

    Two scanning probe microscopy techniques—near-field scanning microwave microscopy (SMM) and piezoresponse force microscopy (PFM)—are used to characterize and image tunability in a thin (Ba,Sr)TiO3 film with nanometer scale spatial resolution. While sMIM allows direct probing of tunability by measurement of the change in the dielectric constant, in PFM, tunability can be extracted via electrostrictive response. The near-field microwave imaging and PFM provide similar information about dielectric tunability with PFM capable to deliver quantitative information on tunability with a higher spatial resolution close to 15 nm. This is the first time that information about the dielectric tunability is available on suchmore » length scales.« less