Science.gov

Sample records for solid state maser

  1. New maser emission from nonmetastable ammonia in NGC 7538. IV. Coincident masers in adjacent states of para-ammonia

    SciTech Connect

    Hoffman, Ian M.; Joyce, Spenser A.

    2014-02-20

    We present the first detection of para-ammonia masers in NGC 7538: multiple epochs of observation of the {sup 14}NH{sub 3} (J, K) = (10, 8) and (9,8) lines. We detect both thermal absorption and nonthermal emission in the (10,8) and (9,8) transitions and the absence of a maser in the (11,8) transition. The (9,8) maser is observed to increase in intensity by 40% over six months. Using interferometric observations with a synthesized beam of 0.''25, we find that the (10,8) and (9,8) masers originate at the same sky position near IRS 1. With strong evidence that the (10,8) and (9,8) masers arise in the same volume, we discuss the application of pumping models for the simultaneous excitation of nonmetastable (J > K) para-ammonia states having the same value of K and consecutive values of J. We also present detections of thermal absorption in rotational states ranging in energy from E/k{sub B} ∼ 200 K to 2000 K, and several non-detections in higher-energy states. In particular, we describe the populations in eight adjacent rotational states with K = 6, including two maser transitions, along with the implications for ortho-ammonia pumping models. An existing torus model for molecular gas in the environment of IRS 1 has been applied to the masers; a variety of maser species are shown to agree with the model. Historical and new interferometric observations of {sup 15}NH{sub 3} (3,3) masers in the region indicate a precession of the rotating torus at a rate comparable to continuum-emission-based models of the region. We discuss the general necessity of interferometric observations for diagnosing the excitation state of the masers and for determining the geometry of the molecular environment.

  2. Excited-state hydroxyl maser catalogue from the methanol multibeam survey - I. Positions and variability

    NASA Astrophysics Data System (ADS)

    Avison, A.; Quinn, L. J.; Fuller, G. A.; Caswell, J. L.; Green, J. A.; Breen, S. L.; Ellingsen, S. P.; Gray, M. D.; Pestalozzi, M.; Thompson, M. A.; Voronkov, M. A.

    2016-09-01

    We present the results of the first complete unbaised survey of the Galactic plane for 6035-MHz excited-state hydroxyl (ex-OH) masers undertaken as part of the methanol multibeam (MMB) survey. These observations cover the Galactic longitude ranges 186° < l < 60° including the Galactic Centre. We report the detection of 127 ex-OH masers within the survey region, 47 being new sources. The positions of new detections were determined from interferometric observations with the Australia Telescope Compact Array. We discuss the association of 6035-MHz masers in our survey with the 6668-MHz masers from the MMB Survey, finding 37 likely CH3OH-ex-OH maser pairs with physical separations of ≤0.03 pc and 55 pairings separated by ≤0.1 pc. Using these we calculate for the first time an ex-OH maser lifetime of between 3.3 × 103 and 8.3 × 103 yr. We also discuss the variability of the 6035-MHz masers and detection rates of counterpart 6030-MHz ex-OH masers (28 per cent of our sample having detection at both frequencies).

  3. Solid State Division

    SciTech Connect

    Green, P.H.; Watson, D.M.

    1989-08-01

    This report contains brief discussions on work done in the Solid State Division of Oak Ridge National Laboratory. The topics covered are: Theoretical Solid State Physics; Neutron scattering; Physical properties of materials; The synthesis and characterization of materials; Ion beam and laser processing; and Structure of solids and surfaces. (LSP)

  4. Solid-state configurations

    NASA Technical Reports Server (NTRS)

    Schroeder, K. G.

    1980-01-01

    Two prototype solid-state phased array systems concepts developed for the solar power satellite (SPS) are described. In both concepts, the beam was centered on the rectenna by means of phase conjugation of a pilot signal emanating from the ground. Also discussed are results of solid state studies.

  5. Proposal for a room-temperature diamond maser.

    PubMed

    Jin, Liang; Pfender, Matthias; Aslam, Nabeel; Neumann, Philipp; Yang, Sen; Wrachtrup, Jörg; Liu, Ren-Bao

    2015-01-01

    The application of masers is limited by its demanding working conditions (high vacuum or low temperature). A room-temperature solid-state maser is highly desirable, but the lifetimes of emitters (electron spins) in solids at room temperature are usually too short (∼ns) for population inversion. Masing from pentacene spins in p-terphenyl crystals, which have a long spin lifetime (∼0.1 ms), has been demonstrated. This maser, however, operates only in the pulsed mode. Here we propose a room-temperature maser based on nitrogen-vacancy centres in diamond, which features the longest known solid-state spin lifetime (∼5 ms) at room temperature, high optical pumping efficiency (∼10(6) s(-1)) and material stability. Our numerical simulation demonstrates that a maser with a coherence time of approximately minutes is feasible under readily accessible conditions (cavity Q-factor ∼5 × 10(4), diamond size ∼3 × 3 × 0.5 mm(3) and pump power <10 W). A room-temperature diamond maser may facilitate a broad range of microwave technologies. PMID:26394758

  6. Proposal for a room-temperature diamond maser

    NASA Astrophysics Data System (ADS)

    Jin, Liang; Pfender, Matthias; Aslam, Nabeel; Neumann, Philipp; Yang, Sen; Wrachtrup, Jörg; Liu, Ren-Bao

    2015-09-01

    The application of masers is limited by its demanding working conditions (high vacuum or low temperature). A room-temperature solid-state maser is highly desirable, but the lifetimes of emitters (electron spins) in solids at room temperature are usually too short (~ns) for population inversion. Masing from pentacene spins in p-terphenyl crystals, which have a long spin lifetime (~0.1 ms), has been demonstrated. This maser, however, operates only in the pulsed mode. Here we propose a room-temperature maser based on nitrogen-vacancy centres in diamond, which features the longest known solid-state spin lifetime (~5 ms) at room temperature, high optical pumping efficiency (~106 s-1) and material stability. Our numerical simulation demonstrates that a maser with a coherence time of approximately minutes is feasible under readily accessible conditions (cavity Q-factor ~5 × 104, diamond size ~3 × 3 × 0.5 mm3 and pump power <10 W). A room-temperature diamond maser may facilitate a broad range of microwave technologies.

  7. Proposal for a room-temperature diamond maser

    PubMed Central

    Jin, Liang; Pfender, Matthias; Aslam, Nabeel; Neumann, Philipp; Yang, Sen; Wrachtrup, Jörg; Liu, Ren-Bao

    2015-01-01

    The application of masers is limited by its demanding working conditions (high vacuum or low temperature). A room-temperature solid-state maser is highly desirable, but the lifetimes of emitters (electron spins) in solids at room temperature are usually too short (∼ns) for population inversion. Masing from pentacene spins in p-terphenyl crystals, which have a long spin lifetime (∼0.1 ms), has been demonstrated. This maser, however, operates only in the pulsed mode. Here we propose a room-temperature maser based on nitrogen-vacancy centres in diamond, which features the longest known solid-state spin lifetime (∼5 ms) at room temperature, high optical pumping efficiency (∼106 s−1) and material stability. Our numerical simulation demonstrates that a maser with a coherence time of approximately minutes is feasible under readily accessible conditions (cavity Q-factor ∼5 × 104, diamond size ∼3 × 3 × 0.5 mm3 and pump power <10 W). A room-temperature diamond maser may facilitate a broad range of microwave technologies. PMID:26394758

  8. The Organic Solid State.

    ERIC Educational Resources Information Center

    Cowan, Dwaine O.; Wlygul, Frank M.

    1986-01-01

    Reviews interesting and useful electrical, magnetic, and optical properties of the organic solid state. Offers speculation as to areas of fruitful research. Discusses organic superconductors, conducting organic polymers, organic metals, and traces recent history of creation of organic metals. (JM)

  9. Solid state switch

    DOEpatents

    Merritt, Bernard T.; Dreifuerst, Gary R.

    1994-01-01

    A solid state switch, with reverse conducting thyristors, is designed to operate at 20 kV hold-off voltage, 1500 A peak, 1.0 .mu.s pulsewidth, and 4500 pps, to replace thyratrons. The solid state switch is more reliable, more economical, and more easily repaired. The switch includes a stack of circuit card assemblies, a magnetic assist and a trigger chassis. Each circuit card assembly contains a reverse conducting thyristor, a resistor capacitor network, and triggering circuitry.

  10. Cosmic Masers

    ERIC Educational Resources Information Center

    Dickinson, Dale F.

    1978-01-01

    Intense radiation at microwave frequencies is emitted by certain nebular regions and stellar atmospheres. It is generated by maser action, which does for microwaves what laser action does for light. Describes in detail the types of masers and their action. (Author/MA)

  11. A survey for ground-state OH masers towards a sample of Herbig-Haro objects

    NASA Astrophysics Data System (ADS)

    de Witt, A.; Bietenholz, M.; Booth, R.; Gaylard, M.

    2014-03-01

    Herbig-Haro objects are regions of shocked gas and dust which are produced when collimated outflows from a protostar interact with the surrounding dense gas. They have many similarities to supernova remnants which are interacting with molecular clouds. 1720-MHz OH masers have been identified towards a number of interacting supernova remnants. Observations and models indicate that these masers are shock excited and are produced behind C-type shocks. If conditions behind the shock fronts of Herbig-Haro objects are similarly able to support 1720-MHz OH masers they could be a useful diagnostic tool for star formation. We therefore searched for 1720-MHz OH maser emission towards a sample of 97 Herbig-Haro objects using the Green Bank Radio Telescope. We detected 1720-MHz OH lines in emission in 17 of them, but neither their spectral signature nor follow-up observations with the Very Large Array showed any conclusive evidence of maser emission. We conclude that the emission detected from our single-dish observations must be extended and most likely originates from thermal or quasi-thermal excitation processes. We also investigated the properties of Herbig-Haro shocks more closely and conclude that despite the overall similarities to supernova remnants, the conditions required for maser emission, in particular a sufficient velocity-coherent column density, are not likely to occur in Herbig-Haro objects.

  12. Solid state switch

    DOEpatents

    Merritt, B.T.; Dreifuerst, G.R.

    1994-07-19

    A solid state switch, with reverse conducting thyristors, is designed to operate at 20 kV hold-off voltage, 1,500 A peak, 1.0 [mu]s pulsewidth, and 4,500 pps, to replace thyratrons. The solid state switch is more reliable, more economical, and more easily repaired. The switch includes a stack of circuit card assemblies, a magnetic assist and a trigger chassis. Each circuit card assembly contains a reverse conducting thyristor, a resistor capacitor network, and triggering circuitry. 6 figs.

  13. Solid State Lighting

    SciTech Connect

    Hastbacka, Mildred; Dieckmann, John; Bouza, Antonio

    2013-03-30

    The article discusses solid state lighting technologies. This topic was covered in two previous ASHRAE Journal columns (2010). This article covers advancements in technologies and the associated efficacies. The life-cycle, energy savings and market potential of these technologies are addressed as well.

  14. Solid-State Devices.

    ERIC Educational Resources Information Center

    Sutliff, Ronald D.; And Others

    This self-study course is designed to familiarize Marine Corps enlisted personnel with the principles of solid-state devices and their functions. The course contains four study units. Each study unit begins with a general objective, which is a statement of what the student should learn from the unit. The study units are divided into numbered work…

  15. Solid State Laser

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Titan-CW Ti:sapphire (titanium-doped sapphire) tunable laser is an innovation in solid-state laser technology jointly developed by the Research and Solid State Laser Divisions of Schwartz Electro-optics, Inc. (SEO). SEO is producing the laser for the commercial market, an outgrowth of a program sponsored by Langley Research Center to develop Ti:sapphire technology for space use. SEO's Titan-CW series of Ti:sapphire tunable lasers have applicability in analytical equipment designed for qualitative analysis of carbohydrates and proteins, structural analysis of water, starch/sugar analyses, and measurements of salt in meat. Further applications are expected in semiconductor manufacture, in medicine for diagnosis and therapy, and in biochemistry.

  16. Tunable solid state lasers

    SciTech Connect

    Hammerling, R.; Budgor, A.B.; Pinto, A.

    1985-01-01

    This book presents the papers given at a conference on solid state lasers. Topics considered at the conference included transition-metal-doped lasers, line-narrowed alexandrite lasers, NASA specification, meteorological lidars, laser materials spectroscopy, laser pumped single pass gain, vibronic laser materials growth, crystal growth methods, vibronic laser theory, cross-fertilization through interdisciplinary fields, and laser action of color centers in diamonds.

  17. Solid State Research

    NASA Technical Reports Server (NTRS)

    Shaver, David C.

    1996-01-01

    This report covers in detail the research work of the Solid State Division at Lincoln Laboratory for the period 1 May - 31 July 1996. The topics covered are Electrooptical Devices, Quantum Electronics, Materials Research, Submicrometer Technology, High Speed Electronics, Microelectronics, and Analog Device Technology. Funding is provided primarily by the Air Force, with additional Support provided by the Army, DARPA, Navy, BMDO, NASA, and NIST.

  18. Solid State Research

    NASA Technical Reports Server (NTRS)

    Shaver, David C.

    1995-01-01

    This report covers in detail the research work of the Solid State Division at Lincoln Laboratory for the period 1 May-31 July 1995. The topics covered are: Electrooptical Devices, Quantum Electronics, Materials Research, Submicrometer Technology, High Speed Electronics, Microelectronics, and analog device technology. Funding is provided primarily by the Air Force, with additional Support provided by the Army, ARPA, Navy, BMDO, NASA and NIST.

  19. Solid state research

    NASA Astrophysics Data System (ADS)

    McWhorter, Alan L.

    1995-02-01

    This report covers in detail the research work of the Solid State Division at Lincoln Laboratory for the period 1 May through 31 July 1994. The topics covered are Electrooptical Devices, Quantum Electronics, Materials Research, Submicrometer Technology, High Speed Electronics, Microelectronics, and Analog Device Technology. Funding is provided primarily by the Air Force, with additional support provided by the Army, ARPA, Navy, BMDO, NASA, and NIST.

  20. Solid state research

    NASA Astrophysics Data System (ADS)

    Shaver, David C.

    1994-11-01

    This report covers in detail the research work of the Solid State Division at Lincoln Laboratory for the period 1 August through 31 October 1994. The topics covered are Electrooptical Devices, Quantum Electronics, Materials Research, Submicrometer Technology, High Speed Electronics, Microelectronics, and Analog Device Technology. Funding is provided primarily by the Air Force, with additional support provided by the Army, ARPA, Navy, BMDO, NASA, and NIST.

  1. Solid state optical microscope

    DOEpatents

    Young, Ian T.

    1983-01-01

    A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

  2. Solid state optical microscope

    DOEpatents

    Young, I.T.

    1983-08-09

    A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal. 2 figs.

  3. Solid state thermal engine

    SciTech Connect

    Wayman, C.M.

    1981-01-27

    An improved solid state thermal engine utilizes as a drive member a braided belt fabricated from a memory alloy such as nickel-titanium and nickel-titanium ternary alloys, copper-zinc and copper-zinc ternary alloys, and the like. The braided belt is mounted on a set of pulleys to provide passage through a hot zone where the belt contracts and develops tension, and through a cold zone where it relaxes and stretches. Since more energy is delivered by contraction than is required for relaxation, positive work output results with an efficiency of between onefifth and one-third of the carnot cycle.

  4. Solid state devices

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The Solid State Device research program is directed toward developing innovative devices for space remote and in-situ sensing, and for data processing. Innovative devices can result from the standard structures in innovative materials such as low and high temperature superconductors, strained layer superlattices, or diamond films. Innovative devices can also result from innovative structures achieved using electron tunneling or nanolithography in standard materials. A final step is to use both innovative structures and innovative materials. A new area of emphasis is the miniaturization of sensors and instruments molded by using the techniques of electronic device fabrication to micromachine silicon into micromechanical and electromechanical sensors and actuators.

  5. Solid state oxygen sensor

    DOEpatents

    Garzon, Fernando H.; Chung, Brandon W.; Raistrick, Ian D.; Brosha, Eric L.

    1996-01-01

    Solid state oxygen sensors are provided with a yttria-doped zirconia as an electrolyte and use the electrochemical oxygen pumping of the zirconia electrolyte. A linear relationship between oxygen concentration and the voltage arising at a current plateau occurs when oxygen accessing the electrolyte is limited by a diffusion barrier. A diffusion barrier is formed herein with a mixed electronic and oxygen ion-conducting membrane of lanthanum-containing perovskite or zirconia-containing fluorite. A heater may be used to maintain an adequate oxygen diffusion coefficient in the mixed conducting layer.

  6. Solid state oxygen sensor

    DOEpatents

    Garzon, F.H.; Chung, B.W.; Raistrick, I.D.; Brosha, E.L.

    1996-08-06

    Solid state oxygen sensors are provided with a yttria-doped zirconia as an electrolyte and use the electrochemical oxygen pumping of the zirconia electrolyte. A linear relationship between oxygen concentration and the voltage arising at a current plateau occurs when oxygen accessing the electrolyte is limited by a diffusion barrier. A diffusion barrier is formed herein with a mixed electronic and oxygen ion-conducting membrane of lanthanum-containing perovskite or zirconia-containing fluorite. A heater may be used to maintain an adequate oxygen diffusion coefficient in the mixed conducting layer. 4 figs.

  7. Solid state heat engine

    SciTech Connect

    Cory, J.S.

    1981-12-15

    A compact solid state turbine heat engine can be devised by pairing the nitinol elements. Each element is characterized by being in thermal contact with at least one hot water and one cold water bath and mechanically coupled to at least one driven pulley and driver pulley. A second nitinol element is similarly configured with a driver pulley, driven pulley, hot and cold water bath. The driver pulley associated with the first nitinol element is mechanically coupled to the driven pulley of the second nitinol element. Similarly, the driver pulley of the second nitinol element is mechanically coupled to the driven pulley of the first nitinol element. The paired nitinol elements form a compound solid state turbine engine wherein each nitinol element lies in a single plane and wherein the engine may be combined with a plurality of such pairs for increased power output. The nitinol elements may also incorporate a snubber to limit the strain on the element and the engine may further incorporate a variable radius pulley to increase the efficiency of mechanical conversion.

  8. Packaging of solid state devices

    DOEpatents

    Glidden, Steven C.; Sanders, Howard D.

    2006-01-03

    A package for one or more solid state devices in a single module that allows for operation at high voltage, high current, or both high voltage and high current. Low thermal resistance between the solid state devices and an exterior of the package and matched coefficient of thermal expansion between the solid state devices and the materials used in packaging enables high power operation. The solid state devices are soldered between two layers of ceramic with metal traces that interconnect the devices and external contacts. This approach provides a simple method for assembling and encapsulating high power solid state devices.

  9. Solid state television camera

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The design, fabrication, and tests of a solid state television camera using a new charge-coupled imaging device are reported. An RCA charge-coupled device arranged in a 512 by 320 format and directly compatible with EIA format standards was the sensor selected. This is a three-phase, sealed surface-channel array that has 163,840 sensor elements, which employs a vertical frame transfer system for image readout. Included are test results of the complete camera system, circuit description and changes to such circuits as a result of integration and test, maintenance and operation section, recommendations to improve the camera system, and a complete set of electrical and mechanical drawing sketches.

  10. Solid state power controllers

    NASA Technical Reports Server (NTRS)

    Gibbs, R. S.

    1973-01-01

    The rationale, analysis, design, breadboarding and testing of the incremental functional requirements are reported that led to the development of prototype 1 and 5 Amp dc and 1 Amp ac solid state power controllers (SSPC's). The SSPC's are to be considered for use as a replacement of electro-mechanical relays and circuit breakers in future spacecraft and aircraft. They satisfy the combined function of both the relay and circuit breaker and can be remotely controlled by small signals, typically 10 mA, 5 to 28 Vdc. They have the advantage over conventional relay/circuit breaker systems in that they can be located near utilization equipment and the primary ac or dc bus. The low level control, trip indication and status signals can be circuited by small guage wire for control, computer interface, logic, electrical multiplexing, unboard testing, and power management and distribution purposes. This results in increased system versatility at appreciable weight saving and increased reliability.

  11. Solid state rapid thermocycling

    SciTech Connect

    Beer, Neil Reginald; Spadaccini, Christopher

    2014-05-13

    The rapid thermal cycling of a material is targeted. A solid state heat exchanger with a first well and second well is coupled to a power module. A thermoelectric element is coupled to the first well, the second well, and the power module, is configured to transfer thermal energy from the first well to the second well when current from the power module flows through the thermoelectric element in a first direction, and is configured to transfer thermal energy from the second well to the first well when current from the power module flows through the thermoelectric element in a second direction. A controller may be coupled to the thermoelectric elements, and may switch the direction of current flowing through the thermoelectric element in response to a determination by sensors coupled to the wells that the amount of thermal energy in the wells falls below or exceeds a pre-determined threshold.

  12. A Solid State Pyranometer

    NASA Astrophysics Data System (ADS)

    Dumitrescu, Anca Laura; Paulescu, Marius; Ercuta, Aurel

    2015-12-01

    The construction of a solid state device-based pyranometer designated to broadband irradiance measurements is presented in this paper. The device is built on the physical basis that the temperature difference between two bodies of identical shape and external surface area, identically exposed to the incident radiation, but having different absorption and heat transfer coefficients (e.g. one body is painted white and the other is painted black), is proportional to the incident irradiance. This proportionality may be put in evidence if the two bodies consisting of identical arrays of correspondingly painted semiconductor diodes, due to the thermal behaviour of their p-n junction. It is theoretically predicted and experimentally confirmed that the voltage drop across a diode passed through a constant forward current linearly decreases with the temperature of the junction. In other words, a signal proportional to the irradiance of the light source may be obtained via conventional analog electronics. The calibration of the apparatus, as performed by means of a professional device (LP PYRA 03), indicates a good linearity.

  13. Solid state power controllers

    NASA Technical Reports Server (NTRS)

    Gibbs, R. S.

    1974-01-01

    Solid state power controllers (SSPC's) are to be considered for use as replacements of electromechanical relays and circuit breakers in future spacecraft and aircraft. They satisfy the combined function of both the relay and circuit breaker and can be remotely controlled by small signals, typically 10 mA, 5 to 28 v(dc). They have the advantage over conventional relay/circuit breaker systems in that they can be located near the utilization equipment and the primary ac or dc bus. The low level control, trip indication and status signals can be circuited by small gauge wire for control, computer interface, logic, electrical multiplexing, onboard testing, power management, and distribution purposes. This results in increased system versatility at appreciable weight saving and increased reliability. Conventional systems require the heavy gage load wiring and the control wiring to be routed from the bus to the load to other remote relay contacts, switches, sensors, etc. and to the circuit breaker located in the flight engineer's compartment for purposes of manual reset.

  14. Solid state laser

    NASA Technical Reports Server (NTRS)

    Rines, Glen A. (Inventor); Moulton, Peter F. (Inventor); Harrison, James (Inventor)

    1993-01-01

    A wavelength-tunable, injection-seeded, dispersion-compensated, dispersively-pumped solid state laser includes a lasing medium; a highly reflective mirror; an output coupler; at least one isosceles Brewster prism oriented to the minimum deviation angle between the medium and the mirror for directing light of different wavelengths along different paths; means for varying the angle of the highly reflective mirror relative to the light from at least one Brewster angle for selecting a predetermined laser operating wavelength; a dispersion compensation apparatus associated with the lasing medium; a laser injection seeding port disposed between the dispersion compensation apparatus and one of the mirror and coupler and including a reflective surface at an acute non-Brewster angle to the laser beam for introducing a seed input; a dispersion compensation apparatus associated with the laser medium including opposite chirality optical elements; the lasing medium including a pump surface disposed at an acute angle to the laser beam to define a discrete path for the pumping laser beam separate from the pumped laser beam.

  15. Solid state electrochemical current source

    DOEpatents

    Potanin, Alexander Arkadyevich; Vedeneev, Nikolai Ivanovich

    2002-04-30

    A cathode and a solid state electrochemical cell comprising said cathode, a solid anode and solid fluoride ion conducting electrolyte. The cathode comprises a metal oxide and a compound fluoride containing at least two metals with different valences. Representative compound fluorides include solid solutions of bismuth fluoride and potassium fluoride; and lead fluoride and potassium fluoride. Representative metal oxides include copper oxide, lead oxide, manganese oxide, vanadium oxide and silver oxide.

  16. High power solid state lasers

    SciTech Connect

    Weber, H.

    1988-01-01

    These proceedings discuss the following subjects: trends in materials processing with laser radiation; slabs and high power systems; glasses and new crystals; solid state lasers at HOYA Corp.; lamps, resonators and transmission; glasses as active materials for high average power solid state lasers; flashlamp pumped GGG-crystals; alexandrite lasers; designing telescope resonators; mode operation of neodymium: YAG lasers; intracavity frequency doubling with KTP crystal and thermal effects in cylinder lasers.

  17. Solid State Photovoltaic Research Branch

    SciTech Connect

    Not Available

    1990-09-01

    This report summarizes the progress of the Solid State Photovoltaic Research Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30,l 1989. Six technical sections of the report cover these main areas of SERIs in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Laser Raman and Luminescence Spectroscopy. Sections have been indexed separately for inclusion on the data base.

  18. Solid state electrolyte systems

    SciTech Connect

    Pederson, L.R.; Armstrong, B.L.; Armstrong, T.R.

    1997-12-01

    Lanthanum gallates are a new family of solid electrolytes that exhibit high ionic conductivity and are stable to high temperatures. Compositions have been developed that are as much as a factor of two more conductive than yttria-stabilized zirconia at a given temperature, through partial replacement of lanthanum by calcium, strontium, and/or barium and through partial replacement of gallium by magnesium. Oxide powders were prepared using combustion synthesis techniques developed in this laboratory; these were sintered to >95% of theoretical density and consisted of a single crystalline phase. Electrical conductivities, electron and ion transference numbers, thermal expansion, and phase behavior were evaluated as a function of temperature and oxygen partial pressure. A key advantage of the use of lanthanum gallate electrolytes in solid oxide fuel cells is that the temperature of operation may be lowered to perhaps 800 C, yet provide approximately the same power density as zirconia-based cells operating at 1000 C. Ceramic electrolytes that conduct both oxygen ions and electrons are potentially useful to passively separate pure oxygen from an air source at low cost. In such materials, an oxygen ion flux in one direction is charge-compensated by an opposing electron flux. The authors have examined a wide range of mixed ion and electron conducting perovskite ceramics in the system La{sub 1{minus}x}M{sub x}Co{sub 1{minus}y{minus}z}Fe{sub y}N{sub z}O{sub 3{minus}{delta}}, where M = Sr, Ca, and Ba, and N = Pr, Mn, Ni, Cu, Ti, and Al, as well as mixed conducting brownmillerite ceramics, and have characterized oxygen permeation behavior, defect chemistry, structural and phase stability, and performance as cathodes.

  19. Modern solid state laser materials

    SciTech Connect

    Krupke, W.F.

    1984-06-20

    This document contains visual aids used in an invited talk entitled Modern Solid State Laser Materials, presented at the Conference on Lasers and Electro-Optics (CLEO) held in Anaheim, California, on June 20, 1984. Interest at LLNL in solid state lasers focuses on evaluating the potential of solid state laser media for high average power applications, including inertial fusion power production. This talk identifies the relevant bulk material parameters characterizing average power capacity and uses chromium and neodymium co-doped gadolinium scandium gallium garnet (Nd:Cr:GSGG) as an example of a laser material with improved laser properties relative to Nd:YAG (plausible large-scale growth, more efficient spectral coupling to xenon flashlamp radiation, reduced stimulated emission cross section, adequate thermal shock and optical damage threshold parameters, etc.). Recently measured spectroscopic, kinetic, and thermo-mechanical properties of Nd:Cr:GSGG are given.

  20. Solid-state lithium battery

    SciTech Connect

    Ihlefeld, Jon; Clem, Paul G; Edney, Cynthia; Ingersoll, David; Nagasubramanian, Ganesan; Fenton, Kyle Ross

    2014-11-04

    The present invention is directed to a higher power, thin film lithium-ion electrolyte on a metallic substrate, enabling mass-produced solid-state lithium batteries. High-temperature thermodynamic equilibrium processing enables co-firing of oxides and base metals, providing a means to integrate the crystalline, lithium-stable, fast lithium-ion conductor lanthanum lithium tantalate (La.sub.1/3-xLi.sub.3xTaO.sub.3) directly with a thin metal foil current collector appropriate for a lithium-free solid-state battery.

  1. Physical characteristics of bright Class I methanol masers

    NASA Astrophysics Data System (ADS)

    Leurini, S.; Menten, K. M.; Walmsley, C. M.

    2016-07-01

    44 GHz line is almost always stronger than the 36 GHz maser. By comparison between observed isotropic photon luminosities and our model predictions, we infer maser beam solid angles of roughly 10-3 steradian. Conclusions: We find that the Class I masers can reasonably be separated into three families: the (J + 1)-1-J0-E type series, the (J + 1)0-J1-A type, and the J2-J1-E lines at 25 GHz. The 25 GHz lines behave in a different fashion from the other masers as they are only inverted at high densities above 106 cm-3 in contrast to other Class I masers. Therefore, the detection of maser activity in all three families is a clear indication of high densities.

  2. Solid-state radioluminescent compositions

    DOEpatents

    Clough, Roger L.; Gill, John T.; Hawkins, Daniel B.; Renschler, Clifford L.; Shepodd, Timothy J.; Smith, Henry M.

    1991-01-01

    A solid state radioluminescent composition for light source comprises an optically clear polymer organic matrix containing tritiated organic materials and dyes capable of "red" shifting primary scintillation emissions from the polymer matrix. The tritiated organic materials are made by reducing, with tritium, an unsaturated organic compound that prior to reduction contains olefinic or alkynylic bonds.

  3. Excitation of millimeter and submillimeter water masers

    NASA Technical Reports Server (NTRS)

    Neufeld, David A.; Melnick, Gary J.

    1991-01-01

    The excitation of maser emission in millimeter and submillimeter transitions of interstellar and circumstellar water is considered. An escape probability method is used to determine the equilibrium populations in 349 rotational states of both ortho- and para-water under varying conditions of gas temperature, density, water abundance, and radiation field. It is shown that, under those conditions believed to prevail around late-type stars and within star-forming regions, strong millimeter and submillimeter water maser emission can be generated by collisional excitations by H2. Several maser transitions can have strengths close to that of the 22 GHz line. The water maser line which can be observed from mountaintop facilities and those which will require air- or space-borne platforms are indicated. The exact portion of parameter space in which each maser transition exhibits peak emission is shown.

  4. A search for water masers associated with class II methanol masers - II. Longitude range 341° to 6°

    NASA Astrophysics Data System (ADS)

    Titmarsh, A. M.; Ellingsen, S. P.; Breen, S. L.; Caswell, J. L.; Voronkov, M. A.

    2016-06-01

    This is the second paper in a series of catalogues of 22-GHz water maser observations towards the 6.7-GHz methanol masers from the Methanol Multibeam (MMB) survey. In this paper, we present our water maser observations made with the Australia Telescope Compact Array towards the masers from the MMB survey between l = 341° through the Galactic Centre to l = 6°. Of the 204 6.7-GHz methanol masers in this longitude range, we found 101 to have associated water maser emission (˜50 per cent). We found no difference in the 6.7-GHz methanol maser luminosities of those with and without water masers. In sources where both maser species are observed, the luminosities of the methanol and water masers are weakly correlated. Studying the mid-infrared colours from GLIMPSE (Galactic Legacy Infrared Midplane Survey Extraordinaire), we found no differences between the colours of those sources associated with both methanol and water masers and those associated with just methanol. Comparing the column density and dust mass calculated from the 870-μm thermal dust emission observed by ATLASGAL (APEX Telescope Large Area Survey of the GALaxy), we found no differences between those sources associated with both water and methanol masers and those with methanol only. Since water masers are collisionally pumped and often show emission further away from their accompanying young stellar object (YSO) than the radiatively pumped 6.7-GHz methanol masers, it is likely that water masers are not as tightly correlated to the evolution of the parent YSO and so do not trace such a well-defined evolutionary state as 6.7-GHz methanol masers.

  5. XANES: Solid state mineral analysis

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    Researchers in the field of mineral physics have become aware of new analytical techniques for studying the electronic structure of solids; one such technique is the X ray absorption fine structure (XFAS) method. In this technique the fine structure of the X ray K-edge, for example, can b e employed as a critical probe of t h e intricacies of a crystal structure (P. A. Lee, P. H. Citrin, P. Eisenberger, and B. M. Kincaid, Rev. Mod. Phys., 53, 799, 1981).A similar, related technique, X ray absorption near-edge spectroscopy (XANES), is a relatively unknown method of studying the electronic structure of solids. XANES is new, and due to its complex nature, data on all but very simple solids have not yet been applied rigorously. Among the first XANES results on minerals is the recent study reported by G. Knapp, B. Veal, H. Pan, and T. Klipper (Solid State Comm. 44, 1343, 1982) on perovskites, magnesiowustites, and other 3d oxides in the zircon and spinel groups. The interpretation of these results is still semiquantitative, being based on ground state and basic selection rule considerations. The results show, however, a strong correlation between near-edge spectra and crystal structure.

  6. Solid-state membrane module

    DOEpatents

    Gordon, John Howard; Taylor, Dale M.

    2011-06-07

    Solid-state membrane modules comprising at least one membrane unit, where the membrane unit has a dense mixed conducting oxide layer, and at least one conduit or manifold wherein the conduit or manifold comprises a dense layer and at least one of a porous layer and a slotted layer contiguous with the dense layer. The solid-state membrane modules may be used to carry out a variety of processes including the separating of any ionizable component from a feedstream wherein such ionizable component is capable of being transported through a dense mixed conducting oxide layer of the membrane units making up the membrane modules. For ease of construction, the membrane units may be planar.

  7. Solid-state membrane module

    SciTech Connect

    Hinklin, Thomas Ray; Lewinsohn, Charles Arthur

    2015-06-30

    A module for separating oxygen from an oxygen-containing gaseous mixture comprising planar solid-state membrane units, each membrane unit comprising planar dense mixed conducting oxides layers, planar channel-free porous support layers, and one or more planar intermediate support layers comprising at least one channeled porous support layer. The porosity of the planar channeled porous support layers is less than the porosity of the planar channel-free porous support layers.

  8. Solid-State Nuclear Power

    NASA Technical Reports Server (NTRS)

    George, Jeffrey A.

    2012-01-01

    A strategy for "Solid-State" Nuclear Power is proposed to guide development of technologies and systems into the second 50 years of nuclear spaceflight. The strategy emphasizes a simple and highly integrated system architecture with few moving parts or fluid loops; the leverage of modern advances in materials, manufacturing, semiconductors, microelectromechanical and nanotechnology devices; and the targeted advancement of high temperature nuclear fuels, materials and static power conversion to enable high performance from simple system topologies.

  9. Radiation sensitive solid state switch

    NASA Technical Reports Server (NTRS)

    Hutto, R. J. (Inventor)

    1973-01-01

    A mechanically operable solid state switch suited for use in achieving a variable circuit-switching function is described. This switch is characterized by an annular array of photoresponsive switching devices, disposed in communication with an included source of radiation, and a plurality of interchangeable, mechanically operable interrupter disks. Each disk has a predetermined pattern of transparent and opaque portions. Operative displacement of each disk serves to make and break selected electrical circuits through the photo responsive devices of said array.

  10. Magnetic state selection in atomic frequency and time standards. [hydrogen masers

    NASA Technical Reports Server (NTRS)

    Peters, H. E.

    1982-01-01

    Atomic standards such as those based upon cesium and hydrogen rely upon magnetic state selection to obtain population inversion in the hyperfine transition levels. Use of new design approaches and improved magnetic materials has made it possible to fabricate improved state selectors of small size, and thus the efficiency of utilization of beam flux is greatly improved and the size and weight of the standard is reduced. The sensitivity to magnetic perturbations is also decreased, so that the accuracy and stability of the standard is improved. Several new state selector designs are illustrated and the application to standards utilizing different atomic species is analyzed.

  11. Solid-state proton conductors

    SciTech Connect

    Jewulski, J.R.; Osif, T.L.; Remick, R.J.

    1990-12-01

    The purpose of this program was to survey the field of solid-state proton conductors (SSPC), identify conductors that could be used to develop solid-state fuel cells suitable for use with coal derived fuel gases, and begin the experimental research required for the development of these fuel cells. This document covers the following topics: the history of developments and current status of the SSPC, including a review of proton conducting electrolyte structures, the current status of the medium temperature SSPC development, electrodes for moderate temperature (SSPC) fuel cell, basic material and measurement techniques applicable for SSPC development, modeling and optimization studies. Correlation and optimization studies, to include correlation studies on proton conduction and oxide cathode optimization for the SSPC fuel cell. Experiments with the SSPC fuel cells including the fabrication of the electrolyte disks, apparatus for conducting measurements, the strontium-cerium based electrolyte, the barium-cerium based electrolyte with solid foil electrodes, the barium-cerium based electrolyte with porous electrodes, and conduction mechanisms. 164 refs., 27 figs., 13 tabs.

  12. Solid State Memory Study Final Report

    NASA Technical Reports Server (NTRS)

    Katti, R.

    1994-01-01

    Existing and future solid state nonvolatile memory technologies are described and evaluated in this report. Solid state memory technologies can offer size, speed, power, weight, and ruggedness advantages over conventional moving media storage technologoies such as disk or tape. This technology list is a broad sampling of past, present, emerging, and future solid state memory technologies.

  13. Solid-state optical microscope

    DOEpatents

    Young, I.T.

    1981-01-07

    A solid state optical microscope is described wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. Means for scanning in one of two orthogonal directions are provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

  14. Solid state electrochromic light modulator

    DOEpatents

    Cogan, Stuart F.; Rauh, R. David

    1993-01-01

    An all solid-state variable transmission electrochromic device has a source of charge compensating ions. An inorganic oxide counterelectrode film which on reduction with the accompanying insertion of the charge compensating ions increases its transmission of light of predetermined wavelength is separated from a primary electrochromic film which on reduction with the accompanying insertion of the charge compensating ions decreases its transmission of light of predetermined wavelength by an insulating electrolyte film that transports the charge compensating ions. First and second electrodes are contiguous with the inorganic oxide counter electrode film and the primary electrochromic film, respectively, and separated by the three films.

  15. Solid-State Personal Dosimetry

    NASA Technical Reports Server (NTRS)

    Wrbanek, John D.; Fralick, Gustave C.; Wrbanek, Susan Y.

    2005-01-01

    This document is a web site page, and a data sheet about Personal protection (i.e., space suits) presented to the Radiation and Micrometeoroid Mitigation Technology Focus Group meeting. The website describes the work of the PI to improve solid state personal radiation dosimetry. The data sheet presents work on the active personal radiation detection system that is to provide real-time local radiation exposure information during EVA. Should undue exposure occur, knowledge of the dynamic intensity conditions during the exposure will allow more precise diagnostic assessment of the potential health risk to the exposed individual.

  16. Solid state electrochromic light modulator

    DOEpatents

    Cogan, S.F.; Rauh, R.D.

    1990-07-03

    An all solid-state variable transmission electrochromic device has a source of charge compensating ions. An inorganic oxide counter electrode film which on reduction with the accompanying insertion of the charge compensating ions increases its transmission of light of predetermined wavelength is separated from a primary electrochromic film which on reduction with the accompanying insertion of the charge compensating ions decreases its transmission of light of predetermined wavelength by an insulating electrolyte film that transports the charge compensating ions. First and second electrodes are contiguous with the inorganic oxide counter electrode film and the primary electrochromic film, respectively, and separated by the three films. 4 figs.

  17. Solid state nuclear track detection

    SciTech Connect

    Durrani, S.A.; Bull, R.K.

    1987-01-01

    This book is a basic work on the technique variously known as 'nuclear track analysis', 'track-etch technique', or 'solid state nuclear tract detection'. This has greatly expanded in range, scope and depth since the early 1960's, soon after its discovery, until there is hardly a field now in which it has not found an actual or potential use. Such applications range from archaeology, geology, space physics, medicine and biology to reactor physics and nuclear physics-to name but a few.

  18. Solid state electrochromic light modulator

    DOEpatents

    Cogan, Stuart F.; Rauh, R. David

    1993-12-07

    An all solid-state variable transmission electrochromic device has a source of charge compensating ions. An inorganic oxide counterelectrode film which on reduction with the accompanying insertion of the charge compensating ions increases its transmission of light of predetermined wavelength is separated from a primary electrochromic film which on reduction with the accompanying insertion of the charge compensating ions decreases its transmission of light of predetermined wavelength by an insulating electrolyte film that transports the charge compensating ions. First and second electrodes are contiguous with the inorganic oxide counter electrode film and the primary electrochromic film, respectively, and separated by the three films.

  19. Solid state electrochromic light modulator

    DOEpatents

    Cogan, Stuart F.; Rauh, R. David

    1990-01-01

    An all solid-state variable transmission electrochromic device has a source of charge compensating ions. An inorganic oxide counterelectrode film which on reduction with the accompanying insertion of the charge compensating ions increases its transmission of light of predetermined wavelength is separated from a primary electrochromic film which on reduction with the accompanying insertion of the charge compensating ions decreases its transmission of light of predetermined wavelength by an insulating electrolyte film that transports the charge compensating ions. First and second electrodes are contiguous with the inorganic oxide counter electrode film and the primary electrochromic film, respectively, and separated by the three films.

  20. Solid-state array cameras.

    PubMed

    Strull, G; List, W F; Irwin, E L; Farnsworth, D L

    1972-05-01

    Over the past few years there has been growing interest shown in the rapidly maturing technology of totally solid-state imaging. This paper presents a synopsis of developments made in this field at the Westinghouse ATL facilities with emphasis on row-column organized monolithic arrays of diffused junction phototransistors. The complete processing sequence applicable to the fabrication of modern highdensity arrays is described from wafer ingot preparation to final sensor testing. Special steps found necessary for high yield processing, such as surface etching prior to both sawing and lapping, are discussed along with the rationale behind their adoption. Camera systems built around matrix array photosensors are presented in a historical time-wise progression beginning with the first 50 x 50 element converter developed in 1965 and running through the most recent 400 x 500 element system delivered in 1972. The freedom of mechanical architecture made available to system designers by solid-state array cameras is noted from the description of a bare-chip packaged cubic inch camera. Hybrid scan systems employing one-dimensional line arrays are cited, and the basic tradeoffs to their use are listed. PMID:20119094

  1. Contamination and solid state welds.

    SciTech Connect

    Mills, Bernice E.

    2007-05-01

    Since sensitivity to contamination is one of the verities of solid state joining, there is a need for assessing contamination of the part(s) to be joined, preferably nondestructively while it can be remedied. As the surfaces that are joined in pinch welds are inaccessible and thus provide a greater challenge, most of the discussion is of the search for the origin and effect of contamination on pinch welding and ways to detect and mitigate it. An example of contamination and the investigation and remediation of such a system is presented. Suggestions are made for techniques for nondestructive evaluation of contamination of surfaces for other solid state welds as well as for pinch welds. Surfaces that have good visual access are amenable to inspection by diffuse reflection infrared Fourier transform (DRIFT) spectroscopy. Although other techniques are useful for specific classes of contaminants (such as hydrocarbons), DRIFT can be used most classes of contaminants. Surfaces such as the interior of open tubes or stems that are to be pinch welded can be inspected using infrared reflection spectroscopy. It must be demonstrated whether or not this tool can detect graphite based contamination, which has been seen in stems. For tubes with one closed end, the technique that should be investigated is emission infrared spectroscopy.

  2. Solid state photochemistry of polycarbonates

    NASA Technical Reports Server (NTRS)

    Gupta, A.; Rembaum, A.; Moacanin, J.

    1978-01-01

    The quantum yield of photoFries rearrangement in a polycarbonate film has been analyzed as a function of temperature and humidity on the basis of previously reported (Koyler and Mann, 1977) experimental data. Results indicate that in the homogeneous amorphous phase, photoFries rearrangement is a concerted process proceeding either from the pi star reversed arrow n singlet, in which case it must be subject to considerable self quenching, or from a triplet, presumably the first triplet since the lifetime of higher triplets is expected to be very short in the solid phase. If the parent excited state is the first triplet, chain scission is possibly an independent process, probably occurring from the pi star reversed arrow n singlet. Evidence of chain scission on photodegradation in the solid state includes loss of C-O and C-C bond intensities revealed in the Fourier transform infrared spectra, gel permeation chromotography elution profiles of degraded film samples dissolved in CHCl3, and a decrease in tensile strength and T sub g as photodegradation proceeds. Chain scission is apparently inhibited as photoFries products accumulate.

  3. Solid state Raman image amplification

    NASA Astrophysics Data System (ADS)

    Calmes, Lonnie K.; Murray, James T.; Austin, William L.; Powell, Richard C.

    1998-07-01

    Lite Cycles has developed a new type of eye-safe, range-gated, lidar sensing element based on Solid-state Raman Image Amplification (SSRIA) in a solid-state optical crystal. SSRIA can amplify low-level infrared images with gains greater than 106 with the addition of only quantum-limited noise. The high gains from SSRIA can compensate for low quantum efficiency detectors and can reduce the need for detector cooling. The range-gate of SSRIA is controlled by the pulsewidth of the pump laser and can be as short as 30 - 100 cm for nanosecond pulses and less than 5 mm if picosecond pulses are used. SSRIA results in higher SNR images throughout a broad range of incident light levels, in contrast to the increasing noise factor with reduced gain in image intensified CCDs. A theoretical framework for the optical resolution of SSRIA is presented and it is shown that SSRIA can produce higher resolution than ICCDs. SSRIA is also superior in rejecting unwanted sunlight background, further increasing image SNR, and can be used for real-time optical signal processing. Applications for military use include eye-safe imaging lidars that can be used for autonomous vehicle identification and targeting.

  4. Solid State Lighting Program (Falcon)

    SciTech Connect

    Meeks, Steven

    2012-06-30

    Over the past two years, KLA-Tencor and partners successfully developed and deployed software and hardware tools that increase product yield for High Brightness LED (HBLED) manufacturing and reduce product development and factory ramp times. This report summarizes our development effort and details of how the results of the Solid State Light Program (Falcon) have started to help HBLED manufacturers optimize process control by enabling them to flag and correct identified killer defect conditions at any point of origin in the process manufacturing flow. This constitutes a quantum leap in yield management over current practice. Current practice consists of die dispositioning which is just rejection of bad die at end of process based upon probe tests, loosely assisted by optical in-line monitoring for gross process deficiencies. For the first time, and as a result of our Solid State Lighting Program, our LED manufacturing partners have obtained the software and hardware tools that optimize individual process steps to control killer defects at the point in the processes where they originate. Products developed during our two year program enable optimized inspection strategies for many product lines to minimize cost and maximize yield. The Solid State Lighting Program was structured in three phases: i) the development of advanced imaging modes that achieve clear separation between LED defect types, improves signal to noise and scan rates, and minimizes nuisance defects for both front end and back end inspection tools, ii) the creation of defect source analysis (DSA) software that connect the defect maps from back-end and front-end HBLED manufacturing tools to permit the automatic overlay and traceability of defects between tools and process steps, suppress nuisance defects, and identify the origin of killer defects with process step and conditions, and iii) working with partners (Philips Lumileds) on product wafers, obtain a detailed statistical correlation of automated

  5. Pumping the stellar hydroxyl maser

    NASA Technical Reports Server (NTRS)

    Dickinson, Dale F.

    1987-01-01

    IRAS far-IR flux data for 163 OH maser stars were analyzed to quantify the contributions 35 and 53 microns inversions make to pumping of the hydroxyl maser. The 35 microns transition is from the 3,3 ground state to the 1,5 rotationally excited level and subsequent decay; the 53 microns transition is a change from the ground state to the 1,3 excited level and relaxation. The stars examined included Mira, short period semi-regular and long-period semi-regular variables. Both transition lines had rough parity in contributing to the approximately 8 percent pumping efficiency at 1612 MHz. However, the individual contributions of the lines could not be determined for the stellar population studied.

  6. Modeling and spatial structure of interstellar masers

    NASA Astrophysics Data System (ADS)

    Voronkov, Maxim A.

    2002-09-01

    This thesis presents a study of masers on the methanol, hydroxyl, and water vapor molecules seen in star-forming regions. A modeling of such masers is a complex numerical task where the radiation transfer equation is coupled with the system describing the balance of the level populations. The general method to solve such non-LTE multiline problem is a Monte Carlo method, the algorithm of which was described by Bernes (1979). The latter algorithm appears to account for the radiation field incorrectly. A modification of the Monte-Carlo method which is based on the averaging of formal solutions of the radiation transfer equation is proposed. This method was tested on two models of E-methanol masers in the limiting cases of the hot gas and the hot external radiation, which are probably corresponded to Class I and Class II methanol masers. Another model of the Class II methanol masers developed by Sobolev and Deguchi (1994) involve the pumping through two first torsionally excited states of the methanol molecule. Among other transitions the model predicts a weak maser at 44.9 GHz. The search for this transition towards brightest Class II methanol maser sources was undertaken to confirm the model. The line was detected in W3(OH) and probably NGC 6334F. The arguments in favor of weak masing in W3(OH) is given. The observational studies of interstellar masers are mainly devoted to the interferometric (VLBI) experiments. In this thesis the first space-VLBI observations of OH maser (1665/1667 MHz) were reported. The study with high angular resolution allows us to put a constraint on the interstellar scattering in the direction of the maser OH34.26+0.15. It appears to be about one order of magnitude lower than that obtained using the pulsar data. This fact gives rise to an idea that there is large scale variations in the spatial distribution of the scattering material. In this thesis the detailed study of the star-forming region GL2789 was performed. Using the Medicina 32-m

  7. Inexpensive solid state radiation detector

    NASA Astrophysics Data System (ADS)

    Aplin, Karen; Hastings, Peter; Harrison, R. Giles; Nicoll, Keri

    2015-04-01

    Monitoring of environmental radioactivity is of interest both within the geosciences community and to groups such as the emergency services who need to quickly assess the safety of an environment. Here we present a light weight and inexpensive detector based on solid state technology, that can be easily worn or carried, or used disposably. It responds to gamma radiation and other radioactive particles such as those from space weather and cosmic rays. Unlike traditional technology such as the Geiger counter, the detector can operate at low voltage without the need for step-up circuitry, and it can also distinguish different particle energies. It is suitable for monitoring background radioactivity from cosmic rays and radon as well as responding to higher radioactivity levels. We anticipate that the device will have a broad range of end users, from terrestrial to space applications.

  8. A compact solid state laser

    NASA Astrophysics Data System (ADS)

    Pati, Bhabana; Park, Eric D.; Stebbins, Kenneth

    2016-03-01

    A compact laser producing green wavelength with a volume of < 8 cm3 and a weight of < 80 g finds its application in many fields from military to space based. We built a small solid-state laser that produces 1 mJ of energy per-pulse at a 1 - 20 Hz repetition rate. The laser is passively Q-switched using a Cr4+:YAG saturable absorber to generate pulses <10 ns. A nonlinear crystal doubles the frequency to generate light at 523 nm. The laser is side-pumped by a single bar diode laser using a unique pump cavity to homogenize the pump intensity in the laser rod. The laser components can easily be modified to change the output wavelength from UV to mid IR.

  9. Study of solid state photomultiplier

    NASA Technical Reports Server (NTRS)

    Hays, K. M.; Laviolette, R. A.

    1987-01-01

    Available solid state photomultiplier (SSPM) detectors were tested under low-background, low temperature conditions to determine the conditions producing optimal sensitivity in a space-based astronomy system such as a liquid cooled helium telescope in orbit. Detector temperatures varied between 6 and 9 K, with background flux ranging from 10 to the 13th power to less than 10 to the 6th power photons/square cm-s. Measured parameters included quantum efficiency, noise, dark current, and spectral response. Experimental data were reduced, analyzed, and combined with existing data to build the SSPM data base included herein. The results were compared to analytical models of SSPM performance where appropriate models existed. Analytical models presented here were developed to be as consistent with the data base as practicable. Significant differences between the theory and data are described. Some models were developed or updated as a result of this study.

  10. Hydrogen maser clocks in space for solid-Earth research and time-transfer applications: Experiment overview and evaluation of Russian miniature sapphire loaded cavity

    NASA Technical Reports Server (NTRS)

    Busca, G.; Bernier, L. G.; Silvestrin, P.; Feltham, S.; Gaygerov, B. A.; Tatarenkov, V. M.

    1994-01-01

    The Observatoire Cantonal de Neuchatel (ON) is developing for ESTEC a compact H-maser for space use based upon a miniature sapphire loaded microwave cavity, a technique pioneered at VNIIFTRI. Various contacts between West-European parties, headed by ESA, and the Russian parties, headed by ESA, led to the proposal for flying two H-masers on Meteor 3M, a Russian meteorology satellite in low polar orbit. The experiment will include two masers, one provided by ON and the other by VNIIFTRI. T/F transfer and precise positioning will be performed by both a microwave link, using PRARE equipment, and an optical link, using LASSO-like equipment. The main objectives of the experiment are precise orbit determination and point positioning for geodetic/geophysical research, ultra-accurate time comparison and dissemination as well as in-orbit demonstration of operation and performance of H-masers. Within the scope of a preliminary space H-maser development phase performed for ESTEC at ON in preparation to the joint experiment, a Russian miniature sapphire loaded microwave cavity, on loan from VNIIFTRI, was evaluated in a full-size EFOS hydrogen maser built by ON. The experimental evaluation confirmed the theoretical expectation that with a hydrogen storage volume of only 0.65 liter an atomic quality factor of 1.5 x 10(exp 9) can be obtained for a -105 dBm output power. This represents a theoretical Allan deviation of 1.7 x 10(exp -15) averaged on a 1000 s time interval. From a full-size design to a compact one, therefore, the sacrifice in performance due to the reduction of the storage volume is very small.

  11. Enhanced magnetic Purcell effect in room-temperature masers

    PubMed Central

    Breeze, Jonathan; Tan, Ke-Jie; Richards, Benjamin; Sathian, Juna; Oxborrow, Mark; Alford, Neil McN

    2015-01-01

    Recently, the world’s first room-temperature maser was demonstrated. The maser consisted of a sapphire ring housing a crystal of pentacene-doped p-terphenyl, pumped by a pulsed rhodamine-dye laser. Stimulated emission of microwaves was aided by the high quality factor and small magnetic mode volume of the maser cavity yet the peak optical pumping power was 1.4 kW. Here we report dramatic miniaturization and 2 orders of magnitude reduction in optical pumping power for a room-temperature maser by coupling a strontium titanate resonator with the spin-polarized population inversion provided by triplet states in an optically excited pentacene-doped p-terphenyl crystal. We observe maser emission in a thimble-sized resonator using a xenon flash lamp as an optical pump source with peak optical power of 70 W. This is a significant step towards the goal of continuous maser operation. PMID:25698634

  12. Enhanced magnetic Purcell effect in room-temperature masers.

    PubMed

    Breeze, Jonathan; Tan, Ke-Jie; Richards, Benjamin; Sathian, Juna; Oxborrow, Mark; Alford, Neil McN

    2015-01-01

    Recently, the world's first room-temperature maser was demonstrated. The maser consisted of a sapphire ring housing a crystal of pentacene-doped p-terphenyl, pumped by a pulsed rhodamine-dye laser. Stimulated emission of microwaves was aided by the high quality factor and small magnetic mode volume of the maser cavity yet the peak optical pumping power was 1.4 kW. Here we report dramatic miniaturization and 2 orders of magnitude reduction in optical pumping power for a room-temperature maser by coupling a strontium titanate resonator with the spin-polarized population inversion provided by triplet states in an optically excited pentacene-doped p-terphenyl crystal. We observe maser emission in a thimble-sized resonator using a xenon flash lamp as an optical pump source with peak optical power of 70 W. This is a significant step towards the goal of continuous maser operation. PMID:25698634

  13. Performance of Soviet and US hydrogen masers

    NASA Technical Reports Server (NTRS)

    Uljanov, Adolph A.; Demidov, Nikolai A.; Mattison, Edward M.; Vessot, Robert F. C.; Allan, David W.; Winkler, Gernot M. R.

    1990-01-01

    The frequencies of Soviet- and U.S.-built hydrogen masers located at the Smithsonian Astrophysical Observatory and at the United States Naval Observatory (USNO) were compared with each other and, via Global Positioning System (GPS) common-view measurements, with three primary frequency-reference scales. The best masers were found to have fractional frequency stabilities as low as 6 times 10(exp -16) for averaging times of approximately 10(exp 4) s. Members of the USNO maser ensemble provided frequency prediction better than 1 times 10(exp 14) for periods up to a few weeks. The frequency residuals of these masers, after removal of frequency drift and rate of change of drift, had stabilities of a few parts in 10(exp -15), with serveral masers achieving residual stabilities well below 1 times 10(exp -15) for intervals from 10(exp 5)s to 2 times 10(exp 6)s. The fractional frequency drifts of the 13 masers studied, relative to the primary reference standards, ranged from -0.2 times 10(exp -15)/day to +9.6 times 10(exp -15)/day.

  14. Solid-state rechargeable magnesium battery

    DOEpatents

    Shao, Yuyan; Liu, Jun; Liu, Tianbiao; Li, Guosheng

    2016-09-06

    Embodiments of a solid-state electrolyte comprising magnesium borohydride, polyethylene oxide, and optionally a Group IIA or transition metal oxide are disclosed. The solid-state electrolyte may be a thin film comprising a dispersion of magnesium borohydride and magnesium oxide nanoparticles in polyethylene oxide. Rechargeable magnesium batteries including the disclosed solid-state electrolyte may have a coulombic efficiency .gtoreq.95% and exhibit cycling stability for at least 50 cycles.

  15. Solid state radiative heat pump

    DOEpatents

    Berdahl, P.H.

    1984-09-28

    A solid state radiative heat pump operable at room temperature (300 K) utilizes a semiconductor having a gap energy in the range of 0.03-0.25 eV and operated reversibly to produce an excess or deficit of change carriers as compared equilibrium. In one form of the invention an infrared semiconductor photodiode is used, with forward or reverse bias, to emit an excess or deficit of infrared radiation. In another form of the invention, a homogenous semiconductor is subjected to orthogonal magnetic and electric fields to emit an excess or deficit of infrared radiation. Three methods of enhancing transmission of radiation the active surface of the semiconductor are disclosed. In one method, an anti-refection layer is coated into the active surface of the semiconductor, the anti-reflection layer having an index of refraction equal to the square root of that of the semiconductor. In the second method, a passive layer is speaced trom the active surface of the semiconductor by a submicron vacuum gap, the passive layer having an index of refractive equal to that of the semiconductor. In the third method, a coupler with a paraboloid reflecting surface surface is in contact with the active surface of the semiconductor, the coupler having an index of refraction about the same as that of the semiconductor.

  16. Solid state radiative heat pump

    DOEpatents

    Berdahl, Paul H.

    1986-01-01

    A solid state radiative heat pump (10, 50, 70) operable at room temperature (300.degree. K.) utilizes a semiconductor having a gap energy in the range of 0.03-0.25 eV and operated reversibly to produce an excess or deficit of charge carriers as compared to thermal equilibrium. In one form of the invention (10, 70) an infrared semiconductor photodiode (21, 71) is used, with forward or reverse bias, to emit an excess or deficit of infrared radiation. In another form of the invention (50), a homogeneous semiconductor (51) is subjected to orthogonal magnetic and electric fields to emit an excess or deficit of infrared radiation. Three methods of enhancing transmission of radiation through the active surface of the semiconductor are disclosed. In one method, an anti-reflection layer (19) is coated into the active surface (13) of the semiconductor (11), the anti-reflection layer (19) having an index of refraction equal to the square root of that of the semiconductor (11). In the second method, a passive layer (75) is spaced from the active surface (73) of the semiconductor (71) by a submicron vacuum gap, the passive layer having an index of refractive equal to that of the semiconductor. In the third method, a coupler (91) with a paraboloid reflecting surface (92) is in contact with the active surface (13, 53) of the semiconductor (11, 51), the coupler having an index of refraction about the same as that of the semiconductor.

  17. Solid state safety jumper cables

    DOEpatents

    Kronberg, J.W.

    1993-02-23

    Solid state jumper cables for connecting two batteries in parallel, having two bridge rectifiers for developing a reference voltage, a four-input decoder for determining which terminals are to be connected based on a comparison of the voltage at each of the four terminals to the reference voltage, and a pair of relays for effecting the correct connection depending on the determination of the decoder. No connection will be made unless only one terminal of each battery has a higher voltage than the reference voltage, indicating positive'' terminals, and one has a lower voltage than the reference voltage, indicating negative'' terminals, and that, therefore, the two high voltage terminals may be connected and the two lower voltage terminals may be connected. Current flows once the appropriate relay device is closed. The relay device is preferably a MOSFET (metal oxide semiconductor field effect transistor) combined with a series array of photodiodes that develop MOSFET gate-closing potential when the decoder output causes an LED to light.

  18. Solid state safety jumper cables

    DOEpatents

    Kronberg, James W.

    1993-01-01

    Solid state jumper cables for connecting two batteries in parallel, having two bridge rectifiers for developing a reference voltage, a four-input decoder for determining which terminals are to be connected based on a comparison of the voltage at each of the four terminals to the reference voltage, and a pair of relays for effecting the correct connection depending on the determination of the decoder. No connection will be made unless only one terminal of each battery has a higher voltage than the reference voltage, indicating "positive" terminals, and one has a lower voltage than the reference voltage, indicating "negative" terminals, and that, therefore, the two high voltage terminals may be connected and the two lower voltage terminals may be connected. Current flows once the appropriate relay device is closed. The relay device is preferably a MOSFET (metal oxide semiconductor field effect transistor) combined with a series array of photodiodes that develop MOSFET gate-closing potential when the decoder output causes an LED to light.

  19. High temperature solid state storage cell

    SciTech Connect

    Rea, Jesse R.; Kallianidis, Milton; Kelsey, G. Stephen

    1983-01-01

    A completely solid state high temperature storage cell comprised of a solid rechargeable cathode such as TiS.sub.2, a solid electrolyte which remains solid at the high temperature operating conditions of the cell and which exhibits high ionic conductivity at such elevated temperatures such as an electrolyte comprised of lithium iodide, and a solid lithium or other alkali metal alloy anode (such as a lithium-silicon alloy) with 5-50% by weight of said anode being comprised of said solid electrolyte.

  20. Solid State Reactor Final Report

    SciTech Connect

    Mays, G.T.

    2004-03-10

    The Solid State Reactor (SSR) is an advanced reactor concept designed to take advantage of Oak Ridge National Laboratory's (ORNL's) recently developed graphite foam that has enhanced heat transfer characteristics and excellent high-temperature mechanical properties, to provide an inherently safe, self-regulated, source of heat for power and other potential applications. This work was funded by the U.S. Department of Energy's Nuclear Energy Research Initiative (NERI) program (Project No. 99-064) from August 1999 through September 30, 2002. The initial concept of utilizing the graphite foam as a basis for developing an advanced reactor concept envisioned that a suite of reactor configurations and power levels could be developed for several different applications. The initial focus was looking at the reactor as a heat source that was scalable, independent of any heat removal/power conversion process. These applications might include conventional power generation, isotope production and destruction (actinides), and hydrogen production. Having conducted the initial research on the graphite foam and having performed the scoping parametric analyses from neutronics and thermal-hydraulic perspectives, it was necessary to focus on a particular application that would (1) demonstrate the viability of the overall concept and (2) require a reasonably structured design analysis process that would synthesize those important parameters that influence the concept the most as part of a feasible, working reactor system. Thus, the application targeted for this concept was supplying power for remote/harsh environments and a design that was easily deployable, simplistic from an operational standpoint, and utilized the new graphite foam. Specifically, a 500-kW(t) reactor concept was pursued that is naturally load following, inherently safe, optimized via neutronic studies to achieve near-zero reactivity change with burnup, and proliferation resistant. These four major areas of research

  1. Solid state recorders for airborne reconnaissance

    NASA Astrophysics Data System (ADS)

    Klang, Mark R.

    2003-08-01

    Solid state recorders have become the recorder of choice for meeting airborne ruggedized requirements for reconnaissance and flight test. The cost of solid state recorders have decreased over the past few years that they are now less expense than the traditional high speed tape recorders. CALCULEX, Inc manufactures solid state recorders called MONSSTR (Modular Non-volatile Solid State Recorder). MONSSTR is being used on many different platforms such as F/A-22, Global Hawk, F-14, F-15, F-16, U-2, RF-4, and Tornado. This paper will discuss the advantages of using solid state recorders to meet the airborne reconnaissance requirement and the ability to record instrumentation data. The CALCULEX recorder has the ability to record sensor data and flight test data in the same chassis. This is an important feature because it eliminates additional boxes on the aircraft. The major advantages to using a solid state recorder include; reliability, small size, light weight, and power. Solid state recorders also have a larger storage capacity and higher bandwidth capability than other recording devices.

  2. Solid-state NMR and Membrane Proteins

    PubMed Central

    Opella, Stanley J.

    2015-01-01

    The native environment for a membrane protein is a phospholipid bilayer. Because the protein is immobilized on NMR timescales by the interactions within a bilayer membrane, solid-state NMR methods are essential to obtain high-resolution spectra. Approaches have been developed for both unoriented and oriented samples, however, they all rest on the foundation of the most fundamental aspects solid-state NMR, and the chemical shift and homo- and hetero-nuclear dipole-dipole interactions. Solid-state NMR has advanced sufficiently to enable the structures of membrane proteins to be determined under near-native conditions in phospholipid bilayers. PMID:25681966

  3. Hydrogen-Maser/Ruby-Maser/Quartz-Crystal Oscillator

    NASA Technical Reports Server (NTRS)

    Wang, Rabi T.; Dick, G. John

    1994-01-01

    Highly stable oscillator suitable for use as 100-MHz frequency standard consists of 100-MHz hydrogen maser combined with double-phase-locked-loop receiver. Generates 100-MHz signal with reduced noise. Contains 100-MHz voltage-controlled quartz-crystal oscillator (VCO) locked in phase to superconducting-cavity maser oscillator (SCMO). SCMO, locks in phase to hydrogen maser, phase-locking receiver and its SCMO/ VCO combination to hydrogen maser. Aspects of SCMO described in previous reports, including "Performance of Superconducting-Cavity Maser" (NPO-18175), NASA Tech Briefs, Vol. 15, No. 6. Performances of component oscillators complement each other.

  4. Solid-state light sources getting smart.

    PubMed

    Schubert, E Fred; Kim, Jong Kyu

    2005-05-27

    More than a century after the introduction of incandescent lighting and half a century after the introduction of fluorescent lighting, solid-state light sources are revolutionizing an increasing number of applications. Whereas the efficiency of conventional incandescent and fluorescent lights is limited by fundamental factors that cannot be overcome, the efficiency of solid-state sources is limited only by human creativity and imagination. The high efficiency of solid-state sources already provides energy savings and environmental benefits in a number of applications. However, solid-state sources also offer controllability of their spectral power distribution, spatial distribution, color temperature, temporal modulation, and polarization properties. Such "smart" light sources can adjust to specific environments and requirements, a property that could result in tremendous benefits in lighting, automobiles, transportation, communication, imaging, agriculture, and medicine. PMID:15919985

  5. Concepts for future solid state lighting solutions

    NASA Astrophysics Data System (ADS)

    von Malm, N.; Wirth, R.; Illek, S.; Steegmüller, U.

    2010-08-01

    In this contribution the relevant technological aspects of LED-based lamps for solid state lighting are discussed. In addition to general energy efficiency considerations improvements in LED chip technology and white light generation are presented.

  6. Solid-state diffusion in amorphous zirconolite

    SciTech Connect

    Yang, C.; Dove, M. T.; Trachenko, K.; Zarkadoula, E.; Todorov, I. T.; Geisler, T.; Brazhkin, V. V.

    2014-11-14

    We discuss how structural disorder and amorphization affect solid-state diffusion, and consider zirconolite as a currently important case study. By performing extensive molecular dynamics simulations, we disentangle the effects of amorphization and density, and show that a profound increase of solid-state diffusion takes place as a result of amorphization. Importantly, this can take place at the same density as in the crystal, representing an interesting general insight regarding solid-state diffusion. We find that decreasing the density in the amorphous system increases pre-factors of diffusion constants, but does not change the activation energy in the density range considered. We also find that atomic species in zirconolite are affected differently by amorphization and density change. Our microscopic insights are relevant for understanding how solid-state diffusion changes due to disorder and for building predictive models of operation of materials to be used to encapsulate nuclear waste.

  7. Standards Development for Solid-State Lighting

    SciTech Connect

    2011-12-16

    To accelerate the development and implementation of needed standards for solid-state lighting products, DOE works closely with a network of standards-setting organizations and offers technical assistance and support

  8. Grating enhanced solid-state laser amplifiers

    DOEpatents

    Erlandson, Alvin C.; Britten, Jerald A.

    2010-11-09

    A novel method and apparatus for suppressing ASE and parasitic oscillation modes in a high average power laser is introduced. Such an invention, as disclosed herein, uses diffraction gratings to increase gain, stored energy density, and pumping efficiency of solid-state laser gain media, such as, but not limited to rods, disks and slabs. By coupling predetermined gratings to solid-state gain media, such as crystal or ceramic laser gain media, ASE and parasitic oscillation modes can be effectively suppressed.

  9. Scalar operators in solid-state NMR

    SciTech Connect

    Sun, Boqin

    1991-11-01

    Selectivity and resolution of solid-state NMR spectra are determined by dispersion of local magnetic fields originating from relaxation effects and orientation-dependent resonant frequencies of spin nuclei. Theoretically, the orientation-dependent resonant frequencies can be represented by a set of irreducible tensors. Among these tensors, only zero rank tensors (scalar operators) are capable of providing high resolution NMR spectra. This thesis presents a series of new developments in high resolution solid-state NMR concerning the reconstruction of various scalar operators motion in solid C{sub 60} is analyzed.

  10. Self-protecting solid state isolated switch

    NASA Technical Reports Server (NTRS)

    Hoffman, A. C.; Gooder, S. T.

    1974-01-01

    Solid state switch has following capabilities: (1) Hybrid or IC from compatible with direct mounting on solar array substrate; (2) Continuous signal is not required to hold it in either on or off state; (3) Separate signal lines for on and off control; (4) Electrically isolated from input signals; and (5) Current surges will not cause switch failure.

  11. Protect motors with solid-state overloads

    SciTech Connect

    Forsell, K.A. )

    1993-03-01

    Magnetic motor starters that rely on bimetal or melting alloy overload protection do not provide the flexibility of solid-state overload technology. The point is best illustrated by the number of different overload relay trip curves that describe tripping time as a function of motor current. Solid-state overloads have a trip curve for a cold start with three-phase current, and a family of trip curves for three-phase conditions where the overload and motor are already warm. An overload relay can also be described by its single-phase trip-time curves for cold and warm initial states. All thermal overloads have single phase trip curves that are similar in shape to their three-phase curves. Slower response to phase loss for motor loads less than locked rotor is inherent in thermal overload relay design. The paper describes the power source problem; single-phase problems; thermal overloads versus solid state; and thermal NEMA overload.

  12. Modular nonvolatile solid state recorder (MONSSTR) update

    NASA Astrophysics Data System (ADS)

    Klang, Mark R.; Small, Martin B.; Beams, Tom

    2001-12-01

    Solid state recorders have begun replacing traditional tape recorders in fulfilling the requirement to record images on airborne platforms. With the advances in electro-optical, IR, SAR, Multi and Hyper-spectral sensors and video recording requirements, solid state recorders have become the recorder of choice. Solid state recorders provide the additional storage, higher sustained bandwidth, less power, less weight and smaller footprint to meet the current and future recording requirements. CALCULEX, Inc., manufactures a non-volatile flash memory solid state recorder called the MONSSTR (Modular Non-volatile Solid State Recorder). MONSSTR is being used to record images from many different digital sensors on high performance aircraft such as the RF- 4, F-16 and the Royal Air Force Tornado. MONSSTR, with its internal multiplexer, is also used to record instrumentation data. This includes multiple streams of PCM and multiple channels of 1553 data. Instrumentation data is being recorded by MONSSTR systems in a range of platforms including F-22, F-15, F-16, Comanche Helicopter and US Navy torpedos. MONSSTR can also be used as a cockpit video recorder. This paper will provide an update of the MONSSTR.

  13. Isothermal Equation Of State For Compressed Solids

    NASA Technical Reports Server (NTRS)

    Vinet, Pascal; Ferrante, John

    1989-01-01

    Same equation with three adjustable parameters applies to different materials. Improved equation of state describes pressure on solid as function of relative volume at constant temperature. Even though types of interatomic interactions differ from one substance to another, form of equation determined primarily by overlap of electron wave functions during compression. Consequently, equation universal in sense it applies to variety of substances, including ionic, metallic, covalent, and rare-gas solids. Only three parameters needed to describe equation for given material.

  14. Solid state lithium-iodine primary battery

    SciTech Connect

    Sekido, S.; Ninomiya, Y.; Sotomura, T.

    1984-01-10

    A solid-state primary cell comprising a lithium anode, an iodine cathode containing a charge transfer complex and a solid lithium iodide electrolyte doped with a 1-normal-alkyl-pyridinium iodide. The anode surface can be coated with LiOH or Li/sub 3/N. The iodine cathode comprises a complex of iodine and 1-normal-alkyl-pyridinium iodide and preferably contains titanium dioxide powder, alumina gel powder or silica gel powder admixed with the complex.

  15. Passivation-free solid state battery

    DOEpatents

    Abraham, Kuzhikalail M.; Peramunage, Dharmasena

    1998-01-01

    This invention pertains to passivation-free solid-state rechargeable batteries composed of Li.sub.4 Ti.sub.5 O.sub.12 anode, a solid polymer electrolyte and a high voltage cathode. The solid polymer electrolyte comprises a polymer host, such as polyacrylonitrile, poly(vinyl chloride), poly(vinyl sulfone), and poly(vinylidene fluoride), plasticized by a solution of a Li salt in an organic solvent. The high voltage cathode includes LiMn.sub.2 O.sub.4, LiCoO.sub.2, LiNiO.sub.2 and LiV.sub.2 O.sub.5 and their derivatives.

  16. Passivation-free solid state battery

    DOEpatents

    Abraham, K.M.; Peramunage, D.

    1998-06-16

    This invention pertains to passivation-free solid-state rechargeable batteries composed of Li{sub 4}Ti{sub 5}O{sub 12} anode, a solid polymer electrolyte and a high voltage cathode. The solid polymer electrolyte comprises a polymer host, such as polyacrylonitrile, poly(vinyl chloride), poly(vinyl sulfone), and poly(vinylidene fluoride), plasticized by a solution of a Li salt in an organic solvent. The high voltage cathode includes LiMn{sub 2}O{sub 4}, LiCoO{sub 2}, LiNiO{sub 2} and LiV{sub 2}O{sub 5} and their derivatives. 5 figs.

  17. Solid state physics of transuranics

    SciTech Connect

    Terminello, L J; Allen, P G; Shuh, D K; Terry, J

    2000-08-22

    The experimental validation of first principals calculations of plutonium and its alloys is an important part of LLNL's science-based stockpile stewardship mission. This project has addressed this issue in the following ways. We have measured the electronic structure of U, Pu, and their alloys using valence band photoemission (PES), Soft X-Ray fluorescence (SXF), and X-Ray Absorption Spectroscopy (XAS). In the long term, this will allow a direct comparison between calculated and measured density of electronic states, identifying the degree of f-electron localization in the alloys, and thus, permit selection of the best modeling code.

  18. Solid state division progress report, period ending February 29, 1980

    SciTech Connect

    Not Available

    1980-09-01

    Research is reported concerning theoretical solid state physics; surface and near-surface properties of solids; defects in solids; transport properties of solids; neutron scattering; crystal growth and characterization; and isotope research materials.

  19. Is solid state the future of lighting?

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, Douglas A.

    2004-01-01

    The rapid pace of solid state technological development over the past four decades has resulted in almost universal acceptance of the phrase "Moore's Law," whether it is used accurately to refer to the exponential increase in computer processor power or to refer to some more amorphous scope of rapid change. More recent breakthroughs in LED science and engineering have precipitated a vigorous discussion of the depth and pace with which solid state light sources will penetrate the $50-billion world-wide lighting market. This discussion has not two perspectives but many, and each perspective can provide valuable insight into key issues that will determine the role that solid state technology will play in the lighting market of 2020 and beyond.

  20. Solid state recording current meter conversion

    USGS Publications Warehouse

    Cheng, Ralph T.; Wang, Lichen

    1985-01-01

    The authors describe the conversion of an Endeco-174 current meter to a solid-state recording current meter. A removable solid-state module was designed to fit in the space originally occupied by an 8-track tape cartridge. The module contains a CPU and 128 kilobytes of nonvolatile CMOS memory. The solid-state module communicates with any terminal or computer using an RS-232C interface at 4800 baud rate. A primary consideration for conversion was to keep modifications of the current meter to a minimum. The communication protocol was designed to emulate the Endeco tape translation unit, thus the need for a translation unit was eliminated and the original data reduction programs can be used without any modification. After conversion, the data recording section of the current meter contains no moving parts; the storage capacity of the module is equivalent to that of the original tape cartridge.

  1. Driver circuit for solid state light sources

    DOEpatents

    Palmer, Fred; Denvir, Kerry; Allen, Steven

    2016-02-16

    A driver circuit for a light source including one or more solid state light sources, a luminaire including the same, and a method of so driving the solid state light sources are provided. The driver circuit includes a rectifier circuit that receives an alternating current (AC) input voltage and provides a rectified AC voltage. The driver circuit also includes a switching converter circuit coupled to the light source. The switching converter circuit provides a direct current (DC) output to the light source in response to the rectified AC voltage. The driver circuit also includes a mixing circuit, coupled to the light source, to switch current through at least one solid state light source of the light source in response to each of a plurality of consecutive half-waves of the rectified AC voltage.

  2. Monolithic solid-state lasers for spaceflight

    NASA Astrophysics Data System (ADS)

    Krainak, Michael A.; Yu, Anthony W.; Stephen, Mark A.; Merritt, Scott; Glebov, Leonid; Glebova, Larissa; Ryasnyanskiy, Aleksandr; Smirnov, Vadim; Mu, Xiaodong; Meissner, Stephanie; Meissner, Helmuth

    2015-02-01

    A new solution for building high power, solid state lasers for space flight is to fabricate the whole laser resonator in a single (monolithic) structure or alternatively to build a contiguous diffusion bonded or welded structure. Monolithic lasers provide numerous advantages for space flight solid-state lasers by minimizing misalignment concerns. The closed cavity is immune to contamination. The number of components is minimized thus increasing reliability. Bragg mirrors serve as the high reflector and output coupler thus minimizing optical coatings and coating damage. The Bragg mirrors also provide spectral and spatial mode selection for high fidelity. The monolithic structure allows short cavities resulting in short pulses. Passive saturable absorber Q-switches provide a soft aperture for spatial mode filtering and improved pointing stability. We will review our recent commercial and in-house developments toward fully monolithic solid-state lasers.

  3. Density functional theory in the solid state

    PubMed Central

    Hasnip, Philip J.; Refson, Keith; Probert, Matt I. J.; Yates, Jonathan R.; Clark, Stewart J.; Pickard, Chris J.

    2014-01-01

    Density functional theory (DFT) has been used in many fields of the physical sciences, but none so successfully as in the solid state. From its origins in condensed matter physics, it has expanded into materials science, high-pressure physics and mineralogy, solid-state chemistry and more, powering entire computational subdisciplines. Modern DFT simulation codes can calculate a vast range of structural, chemical, optical, spectroscopic, elastic, vibrational and thermodynamic phenomena. The ability to predict structure–property relationships has revolutionized experimental fields, such as vibrational and solid-state NMR spectroscopy, where it is the primary method to analyse and interpret experimental spectra. In semiconductor physics, great progress has been made in the electronic structure of bulk and defect states despite the severe challenges presented by the description of excited states. Studies are no longer restricted to known crystallographic structures. DFT is increasingly used as an exploratory tool for materials discovery and computational experiments, culminating in ex nihilo crystal structure prediction, which addresses the long-standing difficult problem of how to predict crystal structure polymorphs from nothing but a specified chemical composition. We present an overview of the capabilities of solid-state DFT simulations in all of these topics, illustrated with recent examples using the CASTEP computer program. PMID:24516184

  4. Solid State Lasers from an Efficiency Perspective

    NASA Technical Reports Server (NTRS)

    Barnes, Norman P.

    2007-01-01

    Solid state lasers have remained a vibrant area of research because several major innovations expanded their capability. Major innovations are presented with emphasis focused on the laser efficiency. A product of efficiencies approach is developed and applied to describe laser performance. Efficiency factors are presented in closed form where practical and energy transfer effects are included where needed. In turn, efficiency factors are used to estimate threshold and slope efficiency, allowing a facile estimate of performance. Spectroscopic, thermal, and mechanical data are provided for common solid state laser materials.

  5. Maser pulse emission mechanisms

    NASA Astrophysics Data System (ADS)

    Melrose, D. B.

    Polar cap models of coherent radio emission mechanisms in pulsars are reviewed, noting deficiencies present in models with curvature emission due to bunches and the possibilities of descriptions based on maser processes. The lack of a no-velocity dispersion theory of bunching radiation is noted to make assumptions based on uniform particle velocities questionable. Streaming instability-produced bunching is also subject to inaccuracy when the bunching occurs at distances of over one stellar radius, or when the growth velocity is insufficient. Conditions are defined for successful bunching through particle trapping by waves, and it is mentioned that models with this mechanism offer predictions which do not match data from observations. Similar objections are found with self-bunching, plasma emission, and klystron mechanisms. Maser-emission models are concluded to avoid the problems associated with differences between observed and predicted dispersion delays found in other types of models.

  6. Maser science at Tidbinbilla

    NASA Astrophysics Data System (ADS)

    Horiuchi, Shinji; Lovell, Jim

    2007-03-01

    The 70 m antenna at Canberra Deep Space Communication Complex (Tidbinbilla) is the largest and most sensitive dish in the southern hemisphere, working at 1, 3, 13 and 18 cm, and as such is in high demand from astronomers both in Australia and overseas. In this paper we present the current status of the single dish spectroscopy system and highlight some recent results in maser science.

  7. Radiative instabilities and 1000 second fluctuations in astrophysical masers

    NASA Astrophysics Data System (ADS)

    Scappaticci, Gerardo A.; Watson, William D.

    1992-03-01

    A stability analysis for small (linear) perturbations is presented for the radiation in astrophysical masers treated in the usual, linear maser approximation. Instabilities that oscillate with a period of about L/c, where L is the length of the maser are found. They occur (1) when the maser is partly but not heavily saturated, (2) when the decay rate Gamma for the molecular states is near c/L, and (3) when the product of the brightness temperature T0 of the incident radiation and the angle for the beaming is less than a critical value that depends upon the particular masing transition. A fourth parameter, the fractional inversion in the pumping multiplied by (T0/frequency), determines the importance of spontaneous emission which can eliminate the instabilities. These instabilities are a likely cause for the fluctuations in the radiation from the 18 cm OH masers that have been reported to occur on time scales as short as 1000 s. The calculations are applicable to other types of astrophysical masers as well, and suggest that spontaneous emission will prevent similar instabilities in the H2O and SiO masers.

  8. An Alfven wave maser in the laboratory

    SciTech Connect

    Maggs, J.E.; Morales, G.J.; Carter, T.A.

    2005-01-01

    A frequency selective Alfven wave resonator results from the application of a locally nonuniform magnetic field to a plasma source region between the cathode and anode in a large laboratory device. When a threshold in the plasma discharge current is exceeded, selective amplification produces a highly coherent ({delta}{omega}/{omega}<5x10{sup -3}), large amplitude shear Alfven wave that propagates out of the resonator, through a semitransparent mesh anode, into the adjacent plasma column where the magnetic field is uniform. This phenomenon is similar to that encountered in the operation of masers/lasers at microwave and optical frequencies. The current threshold for maser action is found to depend upon the confinement magnetic field strength B{sub 0}. Its scaling is consistent with the condition for matching the drift speed of the bulk plasma electrons with the phase velocity of the mode in the resonator. The largest spontaneously amplified signals are obtained at low B{sub 0} and large plasma currents. The magnetic fluctuations {delta}B associated with the Alfven maser can be as large as {delta}B/B{sub 0}{approx_equal}1.5% and are observed to affect the plasma current. Steady-state behavior leading to coherent signals lasting until the discharge is terminated can be achieved when the growth conditions are well-above threshold. The maser is observed to evolve in time from an initial m=0 mode to an m=1 mode structure in the transition to the late steady state. The laboratory phenomenon reported is analogous to the Alfven wave maser proposed to exist in naturally occurring, near-earth plasmas.

  9. Entanglement and Squeezing in Solid State Circuits

    SciTech Connect

    Wen Yihuo; Gui Lulong

    2008-11-07

    We investigate the dynamics of a system consisting of a Cooper-pair box and two superconducting transmission line resonators. There exist both linear and nonlinear interactions in such a system. We show that single-photon entanglement state can be generated in a simple way in the linear interaction regime. In nonlinear interaction regime, we derive the Hamiltonian of degenerate three-wave mixing and propose a scheme for generating squeezed state of microwave using the three-wave mixing in solid state circuits. In the following, we design a system for generating squeezed states of nanamechanical resonator.

  10. Solid-state NMR for bacterial biofilms

    NASA Astrophysics Data System (ADS)

    Reichhardt, Courtney; Cegelski, Lynette

    2014-04-01

    Bacteria associate with surfaces and one another by elaborating an extracellular matrix to encapsulate cells, creating communities termed biofilms. Biofilms are beneficial in some ecological niches, but also contribute to the pathogenesis of serious and chronic infectious diseases. New approaches and quantitative measurements are needed to define the composition and architecture of bacterial biofilms to help drive the development of strategies to interfere with biofilm assembly. Solid-state nuclear magnetic resonance (NMR) is uniquely suited to the examination of insoluble and complex macromolecular and whole-cell systems. This article highlights three examples that implement solid-state NMR to deliver insights into bacterial biofilm composition and changes in cell-wall composition as cells transition to the biofilm lifestyle. Most recently, solid-state NMR measurements provided a total accounting of the protein and polysaccharide components in the extracellular matrix of an Escherichia coli biofilm and transformed our qualitative descriptions of matrix composition into chemical parameters that permit quantitative comparisons among samples. We present additional data for whole biofilm samples (cells plus the extracellular matrix) that complement matrix-only analyses. The study of bacterial biofilms by solid-state NMR is an exciting avenue ripe with many opportunities and we close the article by articulating some outstanding questions and future directions in this area.

  11. Nanoscale solid-state cooling: a review.

    PubMed

    Ziabari, Amirkoushyar; Zebarjadi, Mona; Vashaee, Daryoosh; Shakouri, Ali

    2016-09-01

    The recent developments in nanoscale solid-state cooling are reviewed. This includes both theoretical and experimental studies of different physical concepts, as well as nanostructured material design and device configurations. We primarily focus on thermoelectric, thermionic and thermo-magnetic coolers. Particular emphasis is given to the concepts based on metal-semiconductor superlattices, graded materials, non-equilibrium thermoelectric devices, Thomson coolers, and photon assisted Peltier coolers as promising methods for efficient solid-state cooling. Thermomagnetic effects such as magneto-Peltier and Nernst-Ettingshausen cooling are briefly described and recent advances and future trends in these areas are reviewed. The ongoing progress in solid-state cooling concepts such as spin-calorimetrics, electrocalorics, non-equilibrium/nonlinear Peltier devices, superconducting junctions and two-dimensional materials are also elucidated and practical achievements are reviewed. We explain the thermoreflectance thermal imaging microscopy and the transient Harman method as two unique techniques developed for characterization of thermoelectric microrefrigerators. The future prospects for solid-state cooling are briefly summarized. PMID:27519021

  12. Solid-state NMR imaging system

    SciTech Connect

    Gopalsami, N.; Dieckman, S.L.; Ellingson, W.A.

    1990-01-01

    An accessory for use with a solid-state NMR spectrometer includes a special imaging probe with linear, high-field strength gradient fields and high-power broadband RF coils using a back projection method for data acquisition and image reconstruction, and a real-time pulse programmer adaptable for use by a conventional computer for complex high speed pulse sequences.

  13. The Pythagorean Theorem and the Solid State

    ERIC Educational Resources Information Center

    Kelly, Brenda S.; Splittgerber, Allan G.

    2005-01-01

    Packing efficiency and crystal density can be calculated from basic geometric principles employing the Pythagorean theorem, if the unit-cell structure is known. The procedures illustrated have applicability in courses such as general chemistry, intermediate and advanced inorganic, materials science, and solid-state physics.

  14. Solid state lasers - The next 10 years

    NASA Astrophysics Data System (ADS)

    Byer, Robert L.

    1988-10-01

    Major advances in solid state laser technology historically have been preceded by advances in pumping technology. The helical lamp used to pump the early ruby lasers was superseded by the linear flashlamp now used to pump Nd:YAG lasers. The next advance in pumping technology is the diode laser array. The improvements in power and efficiency of the diode laser coupled with the fortuitous spectral overlap of the diode laser emission wavelength with the Nd ion absorption bands near 805 nm have led to a revolution in solid state laser capability. Progress has been rapid with new ions and wavelengths reported in the near infrared from 946 nm to 2010 nm. Frequency extension via nonlinear interactions has led to green and blue sources of coherent radiation. Linewidths of less than 10 kHz have been demonstrated. Overall electrical efficiencies of greater than 10% have been achieved. As diode laser sources decrease in cost, high average power diode laser pumped solid state laser sources will become available. Power levels exceeding 1 kW appear possible. Potential applications of these compact all solid state laser sources to spectroscopy, quantum noise limited sensors, astronomy, and materials processing will be discussed.

  15. Solid-state NMR imaging system

    DOEpatents

    Gopalsami, Nachappa; Dieckman, Stephen L.; Ellingson, William A.

    1992-01-01

    An apparatus for use with a solid-state NMR spectrometer includes a special imaging probe with linear, high-field strength gradient fields and high-power broadband RF coils using a back projection method for data acquisition and image reconstruction, and a real-time pulse programmer adaptable for use by a conventional computer for complex high speed pulse sequences.

  16. Nanoscale solid-state cooling: a review

    NASA Astrophysics Data System (ADS)

    Ziabari, Amirkoushyar; Zebarjadi, Mona; Vashaee, Daryoosh; Shakouri, Ali

    2016-09-01

    The recent developments in nanoscale solid-state cooling are reviewed. This includes both theoretical and experimental studies of different physical concepts, as well as nanostructured material design and device configurations. We primarily focus on thermoelectric, thermionic and thermo-magnetic coolers. Particular emphasis is given to the concepts based on metal–semiconductor superlattices, graded materials, non-equilibrium thermoelectric devices, Thomson coolers, and photon assisted Peltier coolers as promising methods for efficient solid-state cooling. Thermomagnetic effects such as magneto–Peltier and Nernst–Ettingshausen cooling are briefly described and recent advances and future trends in these areas are reviewed. The ongoing progress in solid-state cooling concepts such as spin-calorimetrics, electrocalorics, non-equilibrium/nonlinear Peltier devices, superconducting junctions and two-dimensional materials are also elucidated and practical achievements are reviewed. We explain the thermoreflectance thermal imaging microscopy and the transient Harman method as two unique techniques developed for characterization of thermoelectric microrefrigerators. The future prospects for solid-state cooling are briefly summarized.

  17. Technique for improving solid state mosaic images

    NASA Technical Reports Server (NTRS)

    Saboe, J. M.

    1969-01-01

    Method identifies and corrects mosaic image faults in solid state visual displays and opto-electronic presentation systems. Composite video signals containing faults due to defective sensing elements are corrected by a memory unit that contains the stored fault pattern and supplies the appropriate fault word to the blanking circuit.

  18. Solar-pumped solid state Nd lasers

    NASA Technical Reports Server (NTRS)

    Williams, M. D.; Zapata, L.

    1985-01-01

    Solid state neodymium lasers are considered candidates for space-based polar-pumped laser for continuous power transmission. Laser performance for three different slab laser configurations has been computed to show the excellent power capability of such systems if heat problems can be solved. Ideas involving geometries and materials are offered as potential solutions to the heat problem.

  19. Light activated solid-state opening switches

    SciTech Connect

    Petr, R.A.; Kachen, G.I.; Reilly, J.P.; Schaefer, R.B. ); Heyse, M.W. )

    1993-01-01

    Light-activated solid-state opening switches are shown to be a viable approach for switching inductive circuits. Measured photoswitch performance indicates that light-activated opening switches have the power density ratings needed to develop compact inductive power systems.

  20. Light activated solid-state opening switches

    NASA Astrophysics Data System (ADS)

    Petr, R. A.; Kachen, G. I.; Reilly, J. P.; Schaefer, R. B.; Heyse, M. W.

    1993-01-01

    The paper shows light-activated solid-state opening switches to be a viable approach for switching inductive circuits. Measured photoswitch performance indicates that light-activated opening switches have the power density ratings required to develop compact inductive power systems.

  1. SPS solid state antenna power combiner

    NASA Technical Reports Server (NTRS)

    Fitzsimmons, G. W.

    1980-01-01

    Solid state dc-rf converters offer potential improvements in reliability, mass and low voltage operation, provided that anticipated efficiencies in excess of 80 percent can be realized. Field effect transistors offer the greatest potential in the SPS frequency band at 2.45 GHz. To implement this approach it is essential that means be found to sum the power of many relatively low power solid state sources in a low-loss manner, and that means be provided to properly control the phase of the outputs of the large number of solid state sources required. To avoid the power combining losses associated with circuit hybrids it was proposed that the power from multiple solid state amplifiers be combined by direct coupling of each amplifier's output to the radiating antenna structure. The selected power-combining antenna consists of a unique printed (metalized) microstrip circuit on a ceramic type dielectric substrate which is backed by a shallow lightweight aluminum cavity which sums the power of four microwave sources. The antenna behaves like two one-half wavelength slot-line antennas coupled together via their common cavity structure.

  2. Solid state, S-band, power amplifier

    NASA Technical Reports Server (NTRS)

    Digrindakis, M.

    1973-01-01

    The final design and specifications for a solid state, S-band, power amplifier is reported. Modifications from a previously proposed design were incorporated to improve efficiency and meet input overdrive and noise floor requirements. Reports on the system design, driver amplifier, power amplifier, and voltage and current limiter are included along with a discussion of the testing program.

  3. Coordinated garbage collection for raid array of solid state disks

    DOEpatents

    Dillow, David A; Ki, Youngjae; Oral, Hakki S; Shipman, Galen M; Wang, Feiyi

    2014-04-29

    An optimized redundant array of solid state devices may include an array of one or more optimized solid-state devices and a controller coupled to the solid-state devices for managing the solid-state devices. The controller may be configured to globally coordinate the garbage collection activities of each of said optimized solid-state devices, for instance, to minimize the degraded performance time and increase the optimal performance time of the entire array of devices.

  4. Solid-state dimer method for calculating solid-solid phase transitions

    SciTech Connect

    Xiao, Penghao; Henkelman, Graeme; Sheppard, Daniel; Rogal, Jutta

    2014-05-07

    The dimer method is a minimum mode following algorithm for finding saddle points on a potential energy surface of atomic systems. Here, the dimer method is extended to include the cell degrees of freedom for periodic solid-state systems. Using this method, reaction pathways of solid-solid phase transitions can be determined without having to specify the final state structure or reaction mechanism. Example calculations include concerted phase transitions between CdSe polymorphs and a nucleation and growth mechanism for the A15 to BCC transition in Mo.

  5. Solid State Processing of Bulk Metallic Glasses

    NASA Astrophysics Data System (ADS)

    Eckert, Jurgen

    1998-03-01

    Glasses are generally produced from the undercooled liquid state by rapid quenching methods or quasi-statically at slow cooling by the effective control of heterogeneous nucleation. For metallic systems, the latter method has recently led to the development of multicomponent metallic glasses with large glass forming ability and a wide supercooled liquid region before crystallization. Large-scale bulk samples can now be produced by conventional casting techniques. These materials exhibit advanced engineering properties such as excellent wear behavior, almost theoretical strength and good corrosion resistance, and are highly processable at temperatures above the glass transition temperature. As an alternative to quenching or casting techniques, glass formation can also be achieved by solid state processing without passing through the liquid state. Therefore, mechanical alloying as a special form of solid state reaction technique and subsequent consolidation of the resulting powders above the glass transition temperature can be used to prepare bulk metallic glasses through the powder metallurgy route. This paper surveys results of studies regarding the factors governing glass formation by solid state processing. The thermal stability of mechanically alloyed powders is compared with data for melt quenched samples, showing that basically the same glassy state can be reached approaching it from the liquid or the solid state. Special emphasis is given to the glass forming ranges achievable by the different techniques, and to preparation of nanostructured composite materials based on glassy alloys. The results are discussed with respect to the influence of processing conditions, impurity effects and heterogeneous nucleation of crystalline phases. Examples for consolidated bulk samples from mechanically alloyed powders are presented and compared with data for cast bulk specimens.

  6. New Observations Deepen Mystery Surrounding Water Masers in Elliptical Galaxy

    NASA Astrophysics Data System (ADS)

    individual maser "spots" as their orbital motion carries them across our line of sight. However, in NGC 1052, this does not appear to be the case. Instead of residing within a disk orbiting the possible black hole, the water masers in NGC 1052 may lie in a "jet" of material being ejected by the central engine of the active nucleus. The high-resolution VLBA observations allowed the team of researchers to locate the water masers with respect to the jet. If the masers were in a disk around a black hole, the masers would be expected to lie in a line perpendicular to the jet axis around the radio core. Two "clumps" of maser emission, each composed of several weaker features, were found instead to lie along the jet axis. "The fact that the masers don't lie transverse to the jet axis means that these masers possibly do not trace a molecular disk around a possible black hole, but could be coming from gas either in the jet material itself, or in some molecular gas just in front of the jet," said Claussen. The researchers don't yet know exactly which of the radio continuum brightness peaks represent the true core of the galaxy, but further analysis of existing data taken by other groups in conjunction with the new data will allow them to determine just where the central engine lies with respect to the jet and the water masers. The shape of the spectrum of the water masers in NGC 1052 also is different than that of the other water megamasers. Typical spectra of water masers in spiral galaxies are composed of many narrow, "spiky" features. The maser spectrum in NGC 1052 is broad and relatively smooth. Periodic monitoring of the maser emission in NGC 1052 using single-dish radio telescopes in Germany, Australia, and the United States has been performed over the past two years. In that time, the features of the maser spectrum have drifted toward longer wavelengths, presumably because of velocity changes that affected the Doppler shift of the radio waves. The overall velocity has changed

  7. Timescale algorithms combining cesium clocks and hydrogen masers

    NASA Technical Reports Server (NTRS)

    Breakiron, Lee A.

    1992-01-01

    The United States Naval Observatory (USNO) atomic timescale, formerly based on an ensemble of cesium clocks, is now produced by an ensemble of cesium clocks and hydrogen masers. In order to optimize stability and reliability, equal clock weighting has been replaced by a procedure reflecting the relative, time-varying noise characteristics of the two different types of clocks. Correlation of frequency drift is required, and residual drift is avoided by the eventual complete deweighting of the masers.

  8. Highly repeatable all-solid-state polarization-state generator

    NASA Astrophysics Data System (ADS)

    Yao, X. Steve; Yan, Lianshan; Shi, Yongqiang

    2005-06-01

    We report an all solid-state polarization-state generator that uses magneto-optic polarization rotators. The device can generate either five or six distinctive polarization states uniformly across a Poincaré sphere with repeatability better than 0.1°. It is ideal for polarization analysis, swept-wavelength measurement, and monitoring of polarization-related parameters and signal-to-noise ratios of optical networks.

  9. Passive maser development at NRL

    NASA Technical Reports Server (NTRS)

    White, J. D.; Frank, A.; Folen, V.

    1981-01-01

    The application of passive hydrogen masers to satellites was investigated. The NRL maser is of compact design suitable for the space environment. It is based on a dielectrically loaded sapphire cavity and uses a computer optimized set of four shields. The servo design is a phase sensitive method which directly measures the phase dispersion of the interrogating signal as it passes through the cavity.

  10. Detection of a new type of methanol maser

    NASA Astrophysics Data System (ADS)

    Wilson, T. L.; Walmsley, C. M.; Jewell, P. R.; Snyder, L. E.

    1984-05-01

    The discovery of emission and absorption at 23121 MHz, attributed to the 92 - 101 A+ transition of methanol (CH3OH) is reported. The emission lines are from W3(OH), Orion-KL, and NGC 7538-IRS1; absorption was found toward the compact H II region in W31. Negative results for a number of other regions are given. The emission from W3(OH) is caused by maser amplification of the background continuum source. Maser amplification probably also explains the observed emission from NGC 7538-IRS1. The 92 - 101 A+ maser emission is the first detected from the A symmetry state of methanol and the first methanol maser found outside of Orion-KL.

  11. Mega-masers, Dark Energy and the Hubble Constant

    SciTech Connect

    Lo, Fred K.Y.

    2007-10-15

    Powerful water maser emission (water mega-masers) can be found in accretion disks in the nuclei of some galaxies. Besides providing a measure of the mass at the nucleus, such mega-masers can be used to determine the distance to the host galaxy, based on a kinematic model. We will explain the importance of determining the Hubble Constant to high accuracy for constraining the equation of state of Dark Energy and describe the Mega-maser Cosmology Project that has the goal of determining the Hubble Constant to better than 3%. Time permitting, we will also present the scientific capabilities of the current and future NRAO facilities: ALMA, EVLA, VLBA and GBT, for addressing key astrophysical problems

  12. Solid state mechanochemical processes for better electroceramics.

    PubMed

    Mamoru, Senna

    2014-01-01

    The present short overview focuses on the renovation of solid state processes toward phase pure and well-crystallized complex oxides centered on the electroceramic materials. Elevation of the reactivity and preservation of stoichiometry of the starting mixture or precursor are of universal importance. Mechanical activation, being considered as versatile, may also need reconsideration in view of contamination and process rationalization. After briefly reviewing mechanochemical processes for direct synthesis of complex oxides, solid state processes toward well crystallized fine particles of complex oxides are discussed by starting from mechanochemically derived precursors with subsequent optimized calcination. Case studies were cited from literatures for complex oxides, including author's own experimental studies mainly with BaBi(2)Ta(2)O(9) (BBT), Ba(Mg(1/3)Ta(2/3))O(3) (BMT) and KNbO(3) (KN). The substances discussed are mostly associated with ferroelectric materials, with a few exceptions of iron-containing magnetic materials. PMID:25286196

  13. Evolution of a solid state laser

    NASA Astrophysics Data System (ADS)

    Yamamoto, R. M.; Parker, J. M.; Allen, K. L.; Allmon, R. W.; Alviso, K. F.; Barty, C. P. J.; Bhachu, B. S.; Boley, C. D.; Burnham, A. K.; Combs, R. L.; Cutter, K. P.; Fochs, S. N.; Gonzales, S. A.; Hurd, R. L.; LaFortune, K. N.; Manning, W. J.; McClelland, M. A.; Merrill, R. D.; Molina, L.; Parks, C. W.; Pax, P. H.; Posey, A. S.; Rotter, M. D.; Roy, B. M.; Rubenchik, A. M.; Soules, T. F.; Webb, D. E.

    2007-04-01

    Lawrence Livermore National Laboratory (LLNL) has been developing compact solid state lasers since the 1990's. One of the first lasers to be developed utilized flashlamp pumped architecture and neodymium glass as the laser gain media. In the early 2000's, a diode pumped version of the original flashlamp pumped laser was designed and built, responding to the requirements that a laser system for the military be compact in both size and weight while creating significant power (~100 kW) for the missions envisioned. This paper will discuss the evolution of solid state lasers at LLNL and provide a glimpse into the types of capabilities that could be achieved in the near future.

  14. Solid-state-laser-rod holder

    DOEpatents

    Gettemy, D.J.; Barnes, N.P.; Griggs, J.E.

    1981-08-11

    The disclosure relates to a solid state laser rod holder comprising Invar, copper tubing, and epoxy joints. Materials and coefficients of expansion of the components of the holder combine with the rod to produce a joint which will give before the rod itself will. The rod may be lased at about 70 to 80/sup 0/K and returned from such a temperature to room temperature repeatedly without its or the holder's destruction.

  15. High energy efficient solid state laser sources

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1987-01-01

    Investigations continue of diode-laser-pumped solid-state laser oscillators and nonlinear processes using them as sources. Diode laser array pumped Nd:YAG and Nd:glass lasers have been demonstrated. Theoretical studies of non-planar oscillators have been advanced, producing new designs which should be more resistant to feedback and offer better frequency stability. A monolithic, singly resonant Optical Parametric Oscillator in MgO:LiNbO3 has been operated.

  16. High energy efficient solid state laser sources

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1987-01-01

    Diode-laser-pumped solid-state laser oscillators and nonlinear processes were investigated. A new generation on nonplanar oscillator was fabricated, and it is anticipated that passive linewidths will be pushed to the kilohertz regime. A number of diode-pumped laser transitions were demonstrated in the rod configuration. Second-harmonic conversion efficiencies as high as 15% are routinely obtained in a servo-locked external resonant doubling crystal at 15 mW cw input power levels at 1064 nm.

  17. Pulsed solid state lasers for medicine

    NASA Astrophysics Data System (ADS)

    Kertesz, Ivan; Danileiko, A. Y.; Denker, Boris I.; Kroo, Norbert; Osiko, Vyacheslav V.; Prokhorov, Alexander M.

    1994-02-01

    The effect on living tissues of different pulsed solid state lasers: Nd:YAG ((lambda) equals 1.06 micrometers ) Er:glass (1.54 micrometers ), Ho:YAG (2.1 micrometers ) and Er:YAG (2.94 micrometers ) is compared with the continuous wave Nd:YAG- and CO2-lasers used in operating theaters. Portable Er:glass- and Er:YAG-lasers are developed for surgery/cosmetics and HIV-safe blood testing.

  18. Solid state synthesis of poly(dichlorophosphazene)

    DOEpatents

    Allen, Christopher W.; Hneihen, Azzam S.; Peterson, Eric S.

    2001-01-01

    A method for making poly(dichlorophosphazene) using solid state reactants is disclosed and described. The present invention improves upon previous methods by removing the need for chlorinated hydrocarbon solvents, eliminating complicated equipment and simplifying the overall process by providing a "single pot" two step reaction sequence. This may be accomplished by the condensation reaction of raw materials in the melt phase of the reactants and in the absence of an environmentally damaging solvent.

  19. SPS solid state antenna power combiner

    NASA Technical Reports Server (NTRS)

    Fitzsimmons, G. W.

    1980-01-01

    A concept for a solar power satellite antenna power combiner which utilizes solid state dc-rf converters is described. To avoid the power combining losses associated with circuit hybrids it is proposed that the power from multiple solid state amplifiers be combined by direct coupling of each amplifier's output to the radiating antenna structure. The selected power-combining antenna consists of a printed (metalized) microstrip circuit on a ceramic type dielectric substrate which is backed by a shallow lightweight aluminum cavity which sums the power of four microwave sources. The antenna behaves like two one-half wavelength slot-line antennas coupled together via their common cavity structure. A significant feature of the antenna configuration selected is that the radiated energy is summed to yield a single radiated output phase which represents the average insertion phase of the four power amplifiers. This energy may be sampled and, by comparison with the input signal, one can phase error correct to maintain the insertion phase of all solid state power combining modules at exactly the same value. This insures that the insertion phase of each SPS power combining antenna module is identical. An experiment verification program is described.

  20. Solid-state ring laser gyroscope

    NASA Astrophysics Data System (ADS)

    Schwartz, S.

    The ring laser gyroscope is a rotation sensor used in most kinds of inertial navigation units. It usually consists in a ring cavity filled with a mixture of helium and neon, together with high-voltage pumping electrodes. The use of a gaseous gain medium, while resulting naturally in a stable bidirectional regime enabling rotation sensing, is however the main industrially limiting factor for the ring laser gyroscopes in terms of cost, reliability and lifetime. We study in this book the possibility of substituting for the gaseous gain medium a solid-state medium (diode-pumped Nd-YAG). For this, a theoretical and experimental overview of the lasing regimes of the solid-state ring laser is reported. We show that the bidirectional emission can be obtained thanks to a feedback loop acting on the states of polarization and inducing differential losses proportional to the difference of intensity between the counterpropagating modes. This leads to the achievement of a solid-state ring laser gyroscope, whose frequency response is modified by mode coupling effects. Several configurations, either mechanically or optically based, are then successively studied, with a view to improving the quality of this frequency response. In particular, vibration of the gain crystal along the longitudinal axis appears to be a very promising technique for reaching high inertial performances with a solid-state ring laser gyroscope. Gyrolaser à état solide. Le gyrolaser est un capteur de rotation utilisé dans la plupart des centrales de navigation inertielle. Dans sa forme usuelle, il est constitué d'une cavité laser en anneau remplie d'un mélange d'hélium et de néon pompé par des électrodes à haute tension. L'utilisation d'un milieu amplificateur gazeux, si elle permet de garantir naturellement le fonctionnement bidirectionnel stable nécessaire à la mesure des rotations, constitue en revanche la principale limitation industrielle des gyrolasers actuels en termes de coût, fiabilit

  1. BOOK REVIEW: Solid State Physics: An Introduction

    NASA Astrophysics Data System (ADS)

    Jakoby, Bernhard

    2009-07-01

    There's a wealth of excellent textbooks on solid state physics. The author of the present book is well aware of this fact and does not attempt to write just another one. Rather, he has provided a very compact introduction to solid state physics for third-year students. As we are faced with the continuous appearance interdisciplinary fields and associated study curricula in natural and engineering sciences (biophysics, mechatronics, etc), a compact text in solid state physics would be appreciated by students of these disciplines as well. The book features 11 chapters where each is provided with supplementary discussion questions and problems. The first chapters deal with a review of chemical bonding mechanisms, crystal structures and mechanical properties of solids, which are brief but by no means superficial. The following, somewhat more detailed chapter on thermal properties of lattices includes a nice introduction to phonons. The foundations of solid state electronics are treated in the next three chapters. Here the author first discusses the classical treatment of electronic behaviour in metals (Drude model) and continues with a quantum-theoretical approach starting with the free-electron model and leading to the band structures in conductive solids. The next chapter is devoted to semiconductors and ends with a brief but, with respect to the topical scope, adequate discussion of semiconductor devices. The classical topics of magnetic and dielectric behaviour are treated in the sequel. The book closes with a chapter on superconductivity and a brief chapter covering the modern topics of quantum confinement and aspects of nanoscale physics. In my opinion, the author has succeeded in creating a very concise yet not superficial textbook. The account presented often probes subjects deep enough to lay the basis for a thorough understanding, preparing the reader for more specialized textbooks. For instance, I think that this book may serve as an excellent first

  2. A Model of Solid State Gas Sensors

    NASA Astrophysics Data System (ADS)

    Woestman, J. T.; Brailsford, A. D.; Shane, M.; Logothetis, E. M.

    1997-03-01

    Solid state gas sensors are widely used to measure the concentrations of gases such as CO, CH_4, C_3H_6, H_2, C_3H8 and O2 The applications of these sensors range from air-to-fuel ratio control in combustion processes including those in automotive engines and industrial furnaces to leakage detection of inflammable and toxic gases in domestic and industrial environments. As the need increases to accurately measure smaller and smaller concentrations, problems such as poor selectivity, stability and response time limit the use of these sensors. In an effort to overcome some of these limitations, a theoretical model of the transient behavior of solid state gas sensors has been developed. In this presentation, a model for the transient response of an electrochemical gas sensor to gas mixtures containing O2 and one reducing species, such as CO, is discussed. This model accounts for the transport of the reactive species to the sampling electrode, the catalyzed oxidation/reduction reaction of these species and the generation of the resulting electrical signal. The model will be shown to reproduce the results of published steady state models and to agree with experimental steady state and transient data.

  3. Accurate maser positions for MALT-45

    NASA Astrophysics Data System (ADS)

    Jordan, Christopher; Bains, Indra; Voronkov, Maxim; Lo, Nadia; Jones, Paul; Muller, Erik; Cunningham, Maria; Burton, Michael; Brooks, Kate; Green, James; Fuller, Gary; Barnes, Peter; Ellingsen, Simon; Urquhart, James; Morgan, Larry; Rowell, Gavin; Walsh, Andrew; Loenen, Edo; Baan, Willem; Hill, Tracey; Purcell, Cormac; Breen, Shari; Peretto, Nicolas; Jackson, James; Lowe, Vicki; Longmore, Steven

    2013-10-01

    MALT-45 is an untargeted survey, mapping the Galactic plane in CS (1-0), Class I methanol masers, SiO masers and thermal emission, and high frequency continuum emission. After obtaining images from the survey, a number of masers were detected, but without accurate positions. This project seeks to resolve each maser and its environment, with the ultimate goal of placing the Class I methanol maser into a timeline of high mass star formation.

  4. Solid state dye laser for medical applications

    NASA Astrophysics Data System (ADS)

    Aldag, Henry R.

    1994-06-01

    The development of solid state dye lasers could lead to a major breakthrough in the cost and compactness of a medical device. Advantages include: elimination of the flow system for the gain medium; ease with which to implement wavelength agility or the replacement of a degraded rod or sheet; and toxicity and flammability become a non-issue. Dye lasers have played a role in cardiology, dermatology, and urology. Of these cardiology is of interest to Palomar. The Palomar Model 3010 flashlamp-pumped dye laser medical device was used during phase 1 FDA clinical trials to break-up blood clots that cause heart attacks, a process known as coronary laser thrombolysis. It is the objective of this research and development effort to produce solid matrix lasers that will replace liquid dye lasers in these medical specialties.

  5. Supramolecular interactions in the solid state

    PubMed Central

    Resnati, Giuseppe; Boldyreva, Elena; Bombicz, Petra; Kawano, Masaki

    2015-01-01

    In the last few decades, supramolecular chemistry has been at the forefront of chemical research, with the aim of understanding chemistry beyond the covalent bond. Since the long-range periodicity in crystals is a product of the directionally specific short-range intermolecular interactions that are responsible for molecular assembly, analysis of crystalline solids provides a primary means to investigate intermolecular interactions and recognition phenomena. This article discusses some areas of contemporary research involving supramolecular interactions in the solid state. The topics covered are: (1) an overview and historical review of halogen bonding; (2) exploring non-ambient conditions to investigate intermolecular interactions in crystals; (3) the role of intermolecular interactions in morphotropy, being the link between isostructurality and polymorphism; (4) strategic realisation of kinetic coordination polymers by exploiting multi-interactive linker molecules. The discussion touches upon many of the prerequisites for controlled preparation and characterization of crystalline materials. PMID:26594375

  6. Enhanced electrodes for solid state gas sensors

    DOEpatents

    Garzon, Fernando H.; Brosha, Eric L.

    2001-01-01

    A solid state gas sensor generates an electrical potential between an equilibrium electrode and a second electrode indicative of a gas to be sensed. A solid electrolyte substrate has the second electrode mounted on a first portion of the electrolyte substrate and a composite equilibrium electrode including conterminous transition metal oxide and Pt components mounted on a second portion of the electrolyte substrate. The composite equilibrium electrode and the second electrode are electrically connected to generate an electrical potential indicative of the gas that is being sensed. In a particular embodiment of the present invention, the second electrode is a reference electrode that is exposed to a reference oxygen gas mixture so that the electrical potential is indicative of the oxygen in a gas stream.

  7. Energy compensated solid state gamma dosimeter

    SciTech Connect

    Sinclair, F.; Clapp, A.; Entine, G.; Kronenberg, S.

    1988-02-01

    Solid state semiconductor detectors using pulse mode detection are attractive candidates for real time dosimetry systems. Their high atomic number relative to that of tissue gives a nonlinear response as a function of the photon energy over the range from 30 keV to 10 MeV. An analytical model of a silicon PIN diode has been developed, including the photoelectric and Compton interactions as well as the ejection of the secondary electrons from the sensitive volume. The authors tested a nonlinear pulse height compensation algorithm using calibrated gamma and x-ray fluxes, and find that this approach improves the dose accuracy.

  8. High Speed Solid State Circuit Breaker

    NASA Technical Reports Server (NTRS)

    Podlesak, Thomas F.

    1993-01-01

    The U.S. Army Research Laboratory, Fort Monmouth, NJ, has developed and is installing two 3.3 MW high speed solid state circuit breakers at the Army's Pulse Power Center. These circuit breakers will interrupt 4160V three phase power mains in no more than 300 microseconds, two orders of magnitude faster than conventional mechanical contact type circuit breakers. These circuit breakers utilize Gate Turnoff Thyristors (GTO's) and are currently utility type devices using air cooling in an air conditioned enclosure. Future refinements include liquid cooling, either water or two phase organic coolant, and more advanced semiconductors. Each of these refinements promises a more compact, more reliable unit.

  9. Pulsed Power for Solid-State Lasers

    SciTech Connect

    Gagnon, W; Albrecht, G; Trenholme, J; Newton, M

    2007-04-19

    Beginning in the early 1970s, a number of research and development efforts were undertaken at U.S. National Laboratories with a goal of developing high power lasers whose characteristics were suitable for investigating the feasibility of laser-driven fusion. A number of different laser systems were developed and tested at ever larger scale in pursuit of the optimum driver for laser fusion experiments. Each of these systems had associated with it a unique pulsed power option. A considerable amount of original and innovative engineering was carried out in support of these options. Ultimately, the Solid-state Laser approach was selected as the optimum driver for the application. Following this, the Laser Program at the Lawrence Livermore National Laboratory and the University of Rochester undertook aggressive efforts directed at developing the technology. In particular, at Lawrence Livermore National Laboratory, a series of laser systems beginning with the Cyclops laser and culminating in the present with the National Ignition Facility were developed and tested. As a result, a large amount of design information for solid-state laser pulsed power systems has been documented. Some of it is in the form of published papers, but most of it is buried in internal memoranda, engineering reports and LLNL annual reports. One of the goals of this book is to gather this information into a single useable format, such that it is easily accessed and understood by other engineers and physicists for use with future designs. It can also serve as a primer, which when seriously studied, makes the subsequent reading of original work and follow-up references considerably easier. While this book deals only with the solid-state laser pulsed power systems, in the bibliography we have included a representative cross section of papers and references from much of the very fine work carried out at other institutions in support of different laser approaches. Finally, in recent years, there has

  10. Solid-state turn coordinator display

    NASA Technical Reports Server (NTRS)

    Meredith, B. D.; Crouch, R. K.; Kelly, W. L., IV

    1975-01-01

    A solid state turn coordinator display which employs light emitting diodes (LED's) as the display medium was developed to demonstrate the feasibility of such displays for aircraft applications. The input to the display is supplied by a fluidic inertial rate sensor used in an aircraft wing leveler system. The display is composed of the LED radial display face and the electronics necessary to address and drive the individual lines of LED's. Three levels of brightness are provided to compensate for the different amounts of ambient light present in the cockpit.

  11. Solid state transport-based thermoelectric converter

    DOEpatents

    Hu, Zhiyu

    2010-04-13

    A solid state thermoelectric converter includes a thermally insulating separator layer, a semiconducting collector and an electron emitter. The electron emitter comprises a metal nanoparticle layer or plurality of metal nanocatalyst particles disposed on one side of said separator layer. A first electrically conductive lead is electrically coupled to the electron emitter. The collector layer is disposed on the other side of the separator layer, wherein the thickness of the separator layer is less than 1 .mu.m. A second conductive lead is electrically coupled to the collector layer.

  12. The 60 GHz solid state power amplifier

    NASA Technical Reports Server (NTRS)

    Mcclymonds, J.

    1991-01-01

    A new amplifier architecture was developed during this contract that is superior to any other solid state approach. The amplifier produced 6 watts with 4 percent efficiency over a 2 GHz band at 61.5 GHz. The unit was 7 x 9 x 3 inches in size, 5.5 pounds in weight, and the conduction cooling through the baseplate is suitable for use in space. The amplifier used high efficiency GaAs IMPATT diodes which were mounted in 1-diode circuits, called modules. Eighteen modules were used in the design, and power combining was accomplished with a proprietary passive component called a combiner plate.

  13. Nanoengineering for solid-state lighting.

    SciTech Connect

    Schubert, E. Fred; Koleske, Daniel David; Wetzel, Christian; Lee, Stephen Roger; Missert, Nancy A.; Lin, Shawn-Yu; Crawford, Mary Hagerott; Fischer, Arthur Joseph

    2009-09-01

    This report summarizes results from a 3-year Laboratory Directed Research and Development project performed in collaboration with researchers at Rensselaer Polytechnic Institute. Our collaborative effort was supported by Sandia's National Institute for Nanoengineering and focused on the study and application of nanoscience and nanoengineering concepts to improve the efficiency of semiconductor light-emitting diodes for solid-state lighting applications. The project explored LED efficiency advances with two primary thrusts: (1) the study of nanoscale InGaN materials properties, particularly nanoscale crystalline defects, and their impact on internal quantum efficiency, and (2) nanoscale engineering of dielectric and metal materials and integration with LED heterostructures for enhanced light extraction efficiency.

  14. Solid State Marx Modulators for Emerging Applications

    SciTech Connect

    Kemp, M.A.; /SLAC

    2012-09-14

    Emerging linear accelerator applications increasingly push the boundaries of RF system performance and economics. The power modulator is an integral part of RF systems whose characteristics play a key role in the determining parameters such as efficiency, footprint, cost, stability, and availability. Particularly within the past decade, solid-state switch based modulators have become the standard in high-performance, high power modulators. One topology, the Marx modulator, has characteristics which make it particularly attractive for several emerging applications. This paper is an overview of the Marx topology, some recent developments, and a case study of how this architecture can be applied to a few proposed linear accelerators.

  15. Fast-neutron solid-state dosimeter

    DOEpatents

    Kecker, K.H.; Haywood, F.F.; Perdue, P.T.; Thorngate, J.H.

    1975-07-22

    This patent relates to an improved fast-neutron solid-state dosimeter that does not require separation of materials before it can be read out, that utilizes materials that do not melt or otherwise degrade at about 300$sup 0$C readout temperature, that provides a more efficient dosimeter, and that can be reused. The dosimeters are fabricated by intimately mixing a TL material, such as CaSO$sub 4$:Dy, with a powdered polyphenyl, such as p-sexiphenyl, and hot- pressing the mixture to form pellets, followed by out-gassing in a vacuum furnace at 150$sup 0$C prior to first use dosimeters. (auth)

  16. Programmable solid state atom sources for nanofabrication

    NASA Astrophysics Data System (ADS)

    Han, Han; Imboden, Matthias; Stark, Thomas; Del Corro, Pablo G.; Pardo, Flavio; Bolle, Cristian A.; Lally, Richard W.; Bishop, David J.

    2015-06-01

    In this paper we discuss the development of a MEMS-based solid state atom source that can provide controllable atom deposition ranging over eight orders of magnitude, from ten atoms per square micron up to hundreds of atomic layers, on a target ~1 mm away. Using a micron-scale silicon plate as a thermal evaporation source we demonstrate the deposition of indium, silver, gold, copper, iron, aluminum, lead and tin. Because of their small sizes and rapid thermal response times, pulse width modulation techniques are a powerful way to control the atomic flux. Pulsing the source with precise voltages and timing provides control in terms of when and how many atoms get deposited. By arranging many of these devices into an array, one has a multi-material, programmable solid state evaporation source. These micro atom sources are a complementary technology that can enhance the capability of a variety of nano-fabrication techniques.In this paper we discuss the development of a MEMS-based solid state atom source that can provide controllable atom deposition ranging over eight orders of magnitude, from ten atoms per square micron up to hundreds of atomic layers, on a target ~1 mm away. Using a micron-scale silicon plate as a thermal evaporation source we demonstrate the deposition of indium, silver, gold, copper, iron, aluminum, lead and tin. Because of their small sizes and rapid thermal response times, pulse width modulation techniques are a powerful way to control the atomic flux. Pulsing the source with precise voltages and timing provides control in terms of when and how many atoms get deposited. By arranging many of these devices into an array, one has a multi-material, programmable solid state evaporation source. These micro atom sources are a complementary technology that can enhance the capability of a variety of nano-fabrication techniques. Electronic supplementary information (ESI) available: A document containing further information about device characterization

  17. Evaluation of modern hydrogen masers

    NASA Technical Reports Server (NTRS)

    Kirk, A.; Kuhnle, P.; Sydnor, R. L.

    1983-01-01

    The masers were tested for environmental sensitivities (magnetic field, temperature, barometric pressure) and long-term aging. Allan variance runs of 72 days were made in order to attain averaging times from several seconds to 1 million seconds. Auto- and cross-correlation techniques were used to determine the effects of uncontrolled parameters such as humidity. Three-cornered-hat and other data reduction techniques were used to determine the characteristics of the individual masers.

  18. New interstellar masers in nonmetastable ammonia

    NASA Technical Reports Server (NTRS)

    Madden, S. C.; Irvine, W. M.; Matthews, H. E.; Brown, R. D.; Godfrey, P. D.

    1986-01-01

    The first astronomical detections of several ammonia inversion transitions involving nonmetastable levels with energies as high as 1090 K above the ground state are reported. The (J, K) = (9, 6) inversion transition shows maser-like emission in the directions of W51, NGC 7538, W49, and DR 21(OH). The NH3 (6, 3) line exhibits similar characteristics in W51 but is seen in absorption in NGC 7538. These are the first definite detections of ammonia masers in space. The intensities and narrow line widths (0.5-1.5 km/s) for the emission features are in contrast to the previously detected broad, weak, nonmetastable lines attributed to thermal emission in these sources. Temporal variability appears to be evident in the (9, 6) emission in W49 over a 4 month period. The highly excited (J, K) = (9, 6) and (6, 3) ammonia lines are found in regions containig compact H II regions and strongly infrared sources with associated H2O and OH masers; i.e., in regions of active star formation.

  19. Experimental aspects of solid-state voltammetry

    SciTech Connect

    Wooster, T.T.; Longmire, M.L.; Zhang, H.

    1992-05-15

    This paper describes the properties of poly(ether) polymer electrolytes as solvent media for solid-state voltammetry. Experimental requirements for microelectrode voltammetry and results for the dependency of diffusive transport of electroactive solutes on polymer solvent molecular weight, structure, and temperature (and related phase state) are described for eight poly(ether)s: linear poly(ethylene oxides) MW = 400, 1000, 2000, and 600 000 (Me{sub 2}PEG-400, Me{sub 2}PEG-1000, Me{sub 2}PEG-2000, PEO-600 000), linear poly(propylene oxide) MW = 4000 (PPO-4000), the comb polymer poly(bis[(methoxyethoxy)ethoxy]phosphazine) (MEEP), the block copolymer poly(ether)-poly(urethane urea)(PEUU), and the cross-linked poly(ether) network PEO. 28 refs., 10 figs., 1 tab.

  20. Nanocrystal-enabled solid state bonding.

    SciTech Connect

    San Diego State University, San Diego, CA; Puskar, Joseph David; Tikare, Veena; Garcia Cardona, Cristina; Reece, Mark; Brewer, Luke N.; Holm, Elizabeth Ann

    2010-10-01

    In this project, we performed a preliminary set of sintering experiments to examine nanocrystal-enabled diffusion bonding (NEDB) in Ag-on-Ag and Cu-on-Cu using Ag nanoparticles. The experimental test matrix included the effects of material system, temperature, pressure, and particle size. The nanoparticle compacts were bonded between plates using a customized hot press, tested in shear, and examined post mortem using microscopy techniques. NEDB was found to be a feasible mechanism for low-temperature, low-pressure, solid-state bonding of like materials, creating bonded interfaces that were able to support substantial loads. The maximum supported shear strength varied substantially within sample cohorts due to variation in bonded area; however, systematic variation with fabrication conditions was also observed. Mesoscale sintering simulations were performed in order to understand whether sintering models can aid in understanding the NEDB process. A pressure-assisted sintering model was incorporated into the SPPARKS kinetic Monte Carlo sintering code. Results reproduce most of the qualitative behavior observed in experiments, indicating that simulation can augment experiments during the development of the NEDB process. Because NEDB offers a promising route to low-temperature, low-pressure, solid-state bonding, we recommend further research and development with a goal of devising new NEDB bonding processes to support Sandia's customers.

  1. Solid-state power conversion handbook

    SciTech Connect

    Tarter, R.E.

    1993-01-01

    This new handbook is the first to be devoted to the field of solid-state power conversion. The material in this book is to be used in engineering practice and is oriented toward application rather than theory. The purpose of the book is to assemble in a single volume all the pertinent and comprehensive information necessary to meet the growing demands placed upon solid-state power conversion equipment. These demands include increased efficiency, improved reliability, higher packaging density, improved performance, and meeting safety and electromagnetic compatibility (EMC) requirements. The material presented includes a thorough analysis of fundamental electrical and magnetic aspects of power conversion plus thermal, protection, and reliability considerations. Attention is focused on semi-conductor and magnetic components and on analysis of various topologies. The handbook is organized into four sections. (1) Chapters 1-3 present the relations of various waveforms, transient components with emphasis on power semiconductors and magnetic components. (2) Chapters 4-12 deal with single-level conversion of rectifier circuits, filters, inverters and converters, feedback and stability analysis, and modulators and pulse-forming networks. (3) Chapters 13-16 discuss ancillary topics related to safety, EMC, thermal management, and reliability. (4) Chapters 17-19 cover design and operation of power supplies and systems from a detailed building block standpoint.

  2. Solid state voltammetry and sensors in solids and gases

    SciTech Connect

    Murray, R.W.

    1992-04-01

    This project explores the electrochemical reactivity of electron transfer donor/acceptors dissolved in and diffusing through solid and semi-solid, ionically conductive media. The emphasis is on developing voltammetric experiments that are quantitatively interpretable in terms of the mass transport and electron transfer rates and thermodynamic equilibria of the redox solutes, and to exploit such experiments to probe their chemical and electrochemical behavior in the solid media. Techniques for quantitative voltammetry in solids were essentially unknown prior to initiation of this DOE project. We mainly employ poly(ethers)s containing dissolved metal salts electrolytes ( polymer electrolytes''), as prototype solid and semi-solid solvents. During this award year we have (a) concluded a study of plasticization chemistry in poly (ether) polymer electrolytes, (b) made progress in devising techniques for measuring the rates of electron transfer reactions in solid and semi-solid poly (ether)s, (c) continued efforts to design and understand the behavior of microband electrodes of various widths (0.1 to 10 {mu}m) in voltammetry of redox solutes, and (d) initiated synthetic efforts to attach ethylene oxide chains of various lengths to redox solutes.

  3. Ground-Based Investigations with the Cryogenic Hydrogen Maser

    NASA Technical Reports Server (NTRS)

    Walsworth, Ronald L.; Mattison, Edward; Vessot, Robert F. C.

    2003-01-01

    The cryogenic hydrogen maser (CHM) developed at the Smithsonian Astrophysical Observatory (SAO) was designed to be functionally similar to SAO room temperature hydrogen masers with appropriate modifications made for operation at cryogenic temperatures. A schematic of the SAO CHM is shown in Figure 1, and a description of this device and its operation follows. A beam of molecular hydrogen is dissociated into atoms at room temperature. The resultant beam of atomic hydrogen is then cooled, magnetically state selected, and focused into a quartz storage bulb centered inside of a microwave cavity resonant with the hydrogen hyperfine transition at 1420 MHz. The quartz storage bulb is coated with a superfluid He-4 film, and both the bulb and cavity are maintained near 0.5 K. The maser signal is coupled out inductively and carried to room temperature via semi-rigid coaxial cable. After passing through a room temperature isolator and preamp, the maser signal is detected with a low-noise heterodyne receiver as used in the room temperature SAO hydrogen masers. The maser temperature is lowered to 0.5 K using a recirculating He-3 refrigerator. This refrigerator consists of several cooling stages: a liquid nitrogen stage at 77 K, a liquid 4He bath at 4.2 K, a pumped He-4 pot at approximately 1.7 K, and the pumped, recirculating He-3 stage at 0.5 K. The atomic hydrogen beam, state selector, storage bulb and cavity are all connected inside a single, maser vacuum chamber (MVC). This space is pumped out from below by a turbo pump. Above the MVC, an inlet to the space allows for the input of flowing superfluid 4He film. External to the MVC is a second, outer vacuum chamber (OVC), maintained for operation of the cryostat and also pumped by a turbo pump. Inside the OVC, there is radiation shielding at 77 K and 1.7 K.

  4. Supernova remnant masers: Shock interactions with molecular clouds

    NASA Astrophysics Data System (ADS)

    Hewitt, John William

    Maser emission from the 1720-MHz transition of hydroxyl(OH) has identified shock interactions in 10% of all supernova remnants(SNRs). Such maser-emitting SNRs are also bright in molecular line emission. Though somewhat rare, SNRs interacting with dense molecular clouds are an important class in which to study cosmic ray acceleration, SNR evolution, and effects on the energetics and chemistry of the interstellar medium. To study molecular shocks via a multiwavelength approach, the VLA, GBT, Spitzer Space Telescope have been used in the following ways: (i) With the GBT widespread OH(1720 MHz) emission and absorption in other OH lines is observed across the interaction site. Observations of all four ground-state transitions at 1720, 1667/5 and 1612 MHz allows us to model OH excitation, yielding the temperature, density and OH abundance in the post-shock gas. Maser emission is found to have a higher flux density with the GBT than with high-resolution VLA observations for 10 of 15 observed remnants, suggesting maser emission is present on large spatial scales. (ii) Sensitive VLA observations of select SNRs (W44, IC 443, Kes 69, 3C 391, G357.7+0.3) reveal the nature of enhanced 1720 MHz emission. Numerous weak compact masers as well as diffuse extended emission are detected tracing the shock-front. Zeeman splitting of masers permits the post-shock magnetic field strength and the line of sight field direction to be directly measured. (iii) Rotational lines of molecular hydrogen are detected at the position of several masers with Spitzer IRS spectroscopy between 5 and 35 mm. Excitation of the hydrogen lines requires the passage of a C-type shock through dense molecular gas, in agreement with the conditions derived from OH excitation. The presence of bright ionic lines requires multiple shocks present at the interaction site. (iv) A new survey for SNR-masers has identified four new interacting SNRs within 10 degrees of the Galactic Center. Maser-emitting SNRs are found to

  5. Solid state neutron dosimeter for space applications

    SciTech Connect

    Nagarkar, V.; Entine, G.; Stoppel, P.; Cirignano, L. ); Swinehart, P. )

    1992-08-01

    One of the most important contributions to the radiation exposure of astronauts engaged in space flight is the significant flux of high energy neutrons arising from both primary and secondary sources of ionizing radiation. Under NASA sponsorship, the authors are developing a solid state neutron sensor capable of being incorporated into a very compact, flight instrument to provide high quality real time measurement of this important radiation flux. The dosimeter uses a special, high neutron sensitivity, PIN diode that is insensitive t the other forms of ionizing radiation. The dosimeter will have the ability to measure and record neutron dose over a range of 50 microgray to tens of milligrays (5 millirads to several rads) over a flight of up to 30 days. the performance characteristics of the PIN diode with a detailed description of the overall dosimeter is presented. in this paper.

  6. Solid-State Spectral Light Source System

    NASA Technical Reports Server (NTRS)

    Maffione, Robert; Dana, David

    2011-01-01

    A solid-state light source combines an array of light-emitting diodes (LEDs) with advanced electronic control and stabilization over both the spectrum and overall level of the light output. The use of LEDs provides efficient operation over a wide range of wavelengths and power levels, while electronic control permits extremely stable output and dynamic control over the output. In this innovation, LEDs are used instead of incandescent bulbs. Optical feedback and digital control are used to monitor and regulate the output of each LED. Because individual LEDs generate light within narrower ranges of wavelengths than incandescent bulbs, multiple LEDs are combined to provide a broad, continuous spectrum, or to produce light within discrete wavebands that are suitable for specific radiometric sensors.

  7. Radioactive isotopes in solid state physics

    NASA Astrophysics Data System (ADS)

    Forkel-Wirth, D.

    1996-04-01

    A wide range of solid state physics techniques is using radioactive ion beams, both from on-line and off-line separators. The different techniques can be roughly subdivided into two classes: one, including the hyperfine techniques like Mößbauer spectroscopy (MS), Perturbed Angular Correlation (PAC) spectroscopy, β-NMR and the ion-beam technique of Emission Channeling (EC). They all crucially depend on the availability of radioactive isotopes with very specific decay properties. The second group comprises radio-tracer techniques which combine radioactive probe atoms with conventional semiconductor physics methods like Deep Level Transient Spectroscopy (DLTS), Capacitance Voltage measurements (CV), Hall-effect measurements or Photoluminescence Spectroscopy (PL). They are perfectly feasible without any radioactive probe atom, however, using such isotopes enables the unambiguous chemical identification of impurities. The present paper gives an overview on the potential of nuclear techniques by describing some typical experiments.

  8. Compact high voltage solid state switch

    DOEpatents

    Glidden, Steven C.

    2003-09-23

    A compact, solid state, high voltage switch capable of high conduction current with a high rate of current risetime (high di/dt) that can be used to replace thyratrons in existing and new applications. The switch has multiple thyristors packaged in a single enclosure. Each thyristor has its own gate drive circuit that circuit obtains its energy from the energy that is being switched in the main circuit. The gate drives are triggered with a low voltage, low current pulse isolated by a small inexpensive transformer. The gate circuits can also be triggered with an optical signal, eliminating the trigger transformer altogether. This approach makes it easier to connect many thyristors in series to obtain the hold off voltages of greater than 80 kV.

  9. Efficient scalable solid-state neutron detector

    SciTech Connect

    Moses, Daniel

    2015-06-15

    We report on scalable solid-state neutron detector system that is specifically designed to yield high thermal neutron detection sensitivity. The basic detector unit in this system is made of a {sup 6}Li foil coupled to two crystalline silicon diodes. The theoretical intrinsic efficiency of a detector-unit is 23.8% and that of detector element comprising a stack of five detector-units is 60%. Based on the measured performance of this detector-unit, the performance of a detector system comprising a planar array of detector elements, scaled to encompass effective area of 0.43 m{sup 2}, is estimated to yield the minimum absolute efficiency required of radiological portal monitors used in homeland security.

  10. Solid-state spectral transmissometer and radiometer

    NASA Technical Reports Server (NTRS)

    Carder, K. L.; Steward, R. G.; Payne, P. R.

    1985-01-01

    An in situ instrument designed to measure the spectral attenuation coefficient of seawater and the ocean remote-sensing reflectance from 400 to 750 nm is in the test and development stage. It employs a 256 channel, charge-coupled type of linear array measuring the spectral intensities diffracted by a grating. Examples of the types of data delivered by this instrument have been simulated using a breadboard laboratory instrument and an above-water, solid-state radiometer. Algorithms developed using data from these instruments provide measures of chlorophyll a plus phaeophytin a concentrations from less than 0.1 to 77.0 mg/cu m, gelbstoff spectral absorption coefficients, and detrital spectral backscattering coefficients for waters of the west Florida shelf.

  11. Electronically shielded solid state charged particle detector

    DOEpatents

    Balmer, D.K.; Haverty, T.W.; Nordin, C.W.; Tyree, W.H.

    1996-08-20

    An electronically shielded solid state charged particle detector system having enhanced radio frequency interference immunity includes a detector housing with a detector entrance opening for receiving the charged particles. A charged particle detector having an active surface is disposed within the housing. The active surface faces toward the detector entrance opening for providing electrical signals representative of the received charged particles when the received charged particles are applied to the active surface. A conductive layer is disposed upon the active surface. In a preferred embodiment, a nonconductive layer is disposed between the conductive layer and the active surface. The conductive layer is electrically coupled to the detector housing to provide a substantially continuous conductive electrical shield surrounding the active surface. The inner surface of the detector housing is supplemented with a radio frequency absorbing material such as ferrite. 1 fig.

  12. High-efficiency solid state power amplifier

    NASA Technical Reports Server (NTRS)

    Wallis, Robert E. (Inventor); Cheng, Sheng (Inventor)

    2005-01-01

    A high-efficiency solid state power amplifier (SSPA) for specific use in a spacecraft is provided. The SSPA has a mass of less than 850 g and includes two different X-band power amplifier sections, i.e., a lumped power amplifier with a single 11-W output and a distributed power amplifier with eight 2.75-W outputs. These two amplifier sections provide output power that is scalable from 11 to 15 watts without major design changes. Five different hybrid microcircuits, including high-efficiency Heterostructure Field Effect Transistor (HFET) amplifiers and Monolithic Microwave Integrated Circuit (MMIC) phase shifters have been developed for use within the SSPA. A highly efficient packaging approach enables the integration of a large number of hybrid circuits into the SSPA.

  13. Solid-state curved focal plane arrays

    NASA Technical Reports Server (NTRS)

    Nikzad, Shouleh (Inventor); Hoenk, Michael (Inventor); Jones, Todd (Inventor)

    2010-01-01

    The present invention relates to curved focal plane arrays. More specifically, the present invention relates to a system and method for making solid-state curved focal plane arrays from standard and high-purity devices that may be matched to a given optical system. There are two ways to make a curved focal plane arrays starting with the fully fabricated device. One way, is to thin the device and conform it to a curvature. A second way, is to back-illuminate a thick device without making a thinned membrane. The thick device is a special class of devices; for example devices fabricated with high purity silicon. One surface of the device (the non VLSI fabricated surface, also referred to as the back surface) can be polished to form a curved surface.

  14. Solid-state lighting technology perspective.

    SciTech Connect

    Tsao, Jeffrey Yeenien; Coltrin, Michael Elliott

    2006-08-01

    Solid-State Lighting (SSL) uses inorganic light-emitting diodes (LEDs) and organic light-emitting diodes (OLEDs) to convert electricity into light for illumination. SSL has the potential for enormous energy savings and accompanying environmental benefits if its promise of 50% (or greater) energy efficiencies can be achieved. This report provides a broad summary of the technologies that underlie SSL. The applications for SSL and potential impact on U.S. and world-wide energy consumption, and impact on the human visual experience are discussed. The properties of visible light and different technical metrics to characterize its properties are summarized. The many factors contributing to the capital and operating costs for SSL and traditional lighting sources (incandescent, fluorescent, and high-intensity discharge lamps) are discussed, with extrapolations for future SSL goals. The technologies underlying LEDs and OLEDs are also described, including current and possible alternative future technologies and some of the present limitations.

  15. Solid state synthesis of calcium borohydroxyapatite

    NASA Astrophysics Data System (ADS)

    Güler, H.; Gündoğmaz, G.; Kurtuluş, F.; Çelik, G.; Gacanoğlu, Ş. S.

    2011-11-01

    Calcium borohydroxyapatite was synthesized by the solid-state reaction of colemanite (Ca 2B 6O 11·5H 2O) and diamonium hydrogenphosphate ((NH 4) 2HPO 4) at 1200 °C for 12 h. X-ray diffraction pattern showed only the formation of calcium borohydroxyapatite. The experimental analysis assigned the chemical formula as Ca 10[(PO 4) 5.80(BO 3) 0.20](OH) 2. It was indexed in the hexagonal system with the refined unit cell parameters of a = 9.557(3) Å, c = 6.926(8) Å and space group P6 3/ m. The experimental results verified that if colemanite was used as a primary reactant for both calcium and boron source, the calcium borohydroxyapatite could be obtained.

  16. Efficient scalable solid-state neutron detector

    NASA Astrophysics Data System (ADS)

    Moses, Daniel

    2015-06-01

    We report on scalable solid-state neutron detector system that is specifically designed to yield high thermal neutron detection sensitivity. The basic detector unit in this system is made of a 6Li foil coupled to two crystalline silicon diodes. The theoretical intrinsic efficiency of a detector-unit is 23.8% and that of detector element comprising a stack of five detector-units is 60%. Based on the measured performance of this detector-unit, the performance of a detector system comprising a planar array of detector elements, scaled to encompass effective area of 0.43 m2, is estimated to yield the minimum absolute efficiency required of radiological portal monitors used in homeland security.

  17. Efficient scalable solid-state neutron detector.

    PubMed

    Moses, Daniel

    2015-06-01

    We report on scalable solid-state neutron detector system that is specifically designed to yield high thermal neutron detection sensitivity. The basic detector unit in this system is made of a (6)Li foil coupled to two crystalline silicon diodes. The theoretical intrinsic efficiency of a detector-unit is 23.8% and that of detector element comprising a stack of five detector-units is 60%. Based on the measured performance of this detector-unit, the performance of a detector system comprising a planar array of detector elements, scaled to encompass effective area of 0.43 m(2), is estimated to yield the minimum absolute efficiency required of radiological portal monitors used in homeland security. PMID:26133869

  18. Principles of solid-state power conversion

    NASA Astrophysics Data System (ADS)

    Tarter, R. E.

    1985-12-01

    The purpose of this book is to assemble, in one place, the comprehensive tools necessary to meet the growing demands placed upon solid-state power conversion equipment. Aspects of transient analysis, circuit analysis, and waveforms are discussed, taking into account waveform relations, magnetic fields, dielectric fields, the RL circuit, the RC circuit, the RLC circuit, the RLCR circuit with a DC input, AC circuit analysis, and components scaling. Semiconductors and resistors are considered along with capacitors, transformers, inductors, conductors, rectifiers and filters, phase-control circuits, transistor inverters, thyristor inverters, switching regulators, DC-DC converters, protection and safety, electromagnetic compatibility and grounding, semiconductor and equipment cooling, reliability and quality, regulated power supplies, and uninterruptible power systems. Attention is given to magnetic materials, toroid tape core transformers, permalloy powder cores, a six-phase dual bridge, thermal conduction and resistance, heat pipes, and thermoelectric coolers.

  19. Solid state potentiometric gaseous oxide sensor

    NASA Technical Reports Server (NTRS)

    Wachsman, Eric D. (Inventor); Azad, Abdul Majeed (Inventor)

    2003-01-01

    A solid state electrochemical cell (10a) for measuring the concentration of a component of a gas mixture (12) includes first semiconductor electrode (14) and second semiconductor electrode (16) formed from first and second semiconductor materials, respectively. The materials are selected so as to undergo a change in resistivity upon contacting a gas component, such as CO or NO. An electrolyte (18) is provided in contact with the first and second semiconductor electrodes. A reference cell can be included in contact with the electrolyte. Preferably, a voltage response of the first semiconductor electrode is opposite in slope direction to that of the second semiconductor electrode to produce a voltage response equal to the sum of the absolute values of the control system uses measured pollutant concentrations to direct adjustment of engine combustion conditions.

  20. Electronically shielded solid state charged particle detector

    SciTech Connect

    Balmer, D.K.; Haverty, T.W.; Nordin, C.W.; Tyree, W.H.

    1995-12-31

    An electronically shielded solid state charged particle detector system having enhanced radio frequency interference immunity includes a detector housing with a detector entrance opening for receiving the charged particles. A charged particle detector having an active surface is disposed within the housing. The active surface faces toward the detector entrance opening for providing electrical signals representative of the received charged particles when the received charged particles are applied to the active surface. A conductive layer is disposed upon the active surface. In a preferred embodiment, a nonconductive layer is disposed between the conductive layer and the active surface. The conductive layer is electrically coupled to the detector housing to provide a substantially continuous conductive electrical shield surrounding the active surface. The inner surface of the detector housing is supplemented with a radio frequency absorbing material such as ferrite.

  1. Electronically shielded solid state charged particle detector

    DOEpatents

    Balmer, David K.; Haverty, Thomas W.; Nordin, Carl W.; Tyree, William H.

    1996-08-20

    An electronically shielded solid state charged particle detector system having enhanced radio frequency interference immunity includes a detector housing with a detector entrance opening for receiving the charged particles. A charged particle detector having an active surface is disposed within the housing. The active surface faces toward the detector entrance opening for providing electrical signals representative of the received charged particles when the received charged particles are applied to the active surface. A conductive layer is disposed upon the active surface. In a preferred embodiment, a nonconductive layer is disposed between the conductive layer and the active surface. The conductive layer is electrically coupled to the detector housing to provide a substantially continuous conductive electrical shield surrounding the active surface. The inner surface of the detector housing is supplemented with a radio frequency absorbing material such as ferrite.

  2. Flexible solid-state photoelectrochromic windows

    SciTech Connect

    Pichot, F.; Ferrere, S.; Pitts, R.J.; Gregg, B.A.

    1999-11-01

    Photoelectrochromic smart window technology is extended to include the use of flexible substrates and solid-state electrolytes. This should facilitate their application as retrofit modifications of office windows, where, by blocking incoming solar irradiation, they could substantially lower air-conditioning costs. These devices are based on a dye-sensitized TiO{sub 2} electrode coupled with a 500 nm thick WO{sub 3} electrochromic counter electrode, separated by a cross-linked polymer electrolyte containing LiI. A novel method for preparing conducting nanoporous TiO{sub 2} films is described that allows for the construction of these devices on flexible organic substrates. Colloidal solutions of TiO{sub 2} free of surfactants were spin-coated onto indium-tin oxide coated polyester substrates, resulting in highly transparent films ranging from 100 nm to 1 {micro}m in thickness. Upon annealing at 100 C, these films were strongly adherent and displayed excellent photoconductivity as shown by their current-voltage characteristics. The devices typically transmit 75% of visible light in the bleached state. After a few minutes of exposure to white light (75 mW/cm{sup 2}), the windows turn dark blue, transmitting only 30% of visible light. They spontaneously bleach back to their initial noncolored state upon removal of the light source.

  3. Solid State Technology Meets Collider Challenge

    SciTech Connect

    Hazi, A

    2005-09-20

    Probing the frontiers of particle physics and delving into the mysteries of the universe and its beginnings require machines that can accelerate beams of fundamental particles to very high energies and then collide those beams together, producing a multitude of exotic subatomic particles. The proposed Next Linear Collider (NLC), being developed by Stanford Linear Accelerator Center (SLAC), Lawrence Livermore and Lawrence Berkeley national laboratories, and Fermi National Accelerator Laboratory (Fermilab), is such a machine. The NLC is expected to produce a variety of subatomic particles by smashing together electrons and their antimatter counterparts (positrons) at nearly the speed of light with energies in the teraelectronvolt (TeV) range. Plans are that the NLC will initially operate at 0.5 TeV and ultimately be scaled up to 1.5 TeV. (See S&TR, April 2000, pp. 12-16.) Work at the facility will complement the research to be conducted at another high-energy particle accelerator, the 14-TeV Large Hadron Collider at the European Laboratory for Particle Physics (commonly known by the acronym CERN from its former name) in Geneva, which is scheduled for completion in 2007. Achieving beam energy levels in the TeV range requires modulator systems that can convert ac line power--the same type of power one gets from the wall plug--into dc pulses. Ultimately, these pulses are transformed into radiofrequency (rf) pulses that ''kick'' the particles up to the required energy levels. Livermore scientists and engineers have designed a solid-state modulator to replace oldstyle modulators based on vacuum-tube technology. These new modulators promise to be far more efficient, reliable, and serviceable than the previous components. Livermore's Laboratory Directed Research and Development Program supported the basic research and development on the solid-state modulator technology, and SLAC supported the systems integration.

  4. Solid-state NMR studies of supercapacitors.

    PubMed

    Griffin, John M; Forse, Alexander C; Grey, Clare P

    2016-01-01

    Electrochemical double-layer capacitors, or 'supercapacitors' are attracting increasing attention as high-power energy storage devices for a wide range of technological applications. These devices store charge through electrostatic interactions between liquid electrolyte ions and the surfaces of porous carbon electrodes. However, many aspects of the fundamental mechanism of supercapacitance are still not well understood, and there is a lack of experimental techniques which are capable of studying working devices. Recently, solid-state NMR has emerged as a powerful tool for studying the local environments and behaviour of electrolyte ions in supercapacitor electrodes. In this Trends article, we review these recent developments and applications. We first discuss the basic principles underlying the mechanism of supercapacitance, as well as the key NMR observables that are relevant to the study of supercapacitor electrodes. We then review some practical aspects of the study of working devices using ex situ and in situ methodologies and explain the key advances that these techniques have allowed on the study of supercapacitor charging mechanisms. NMR experiments have revealed that the pores of the carbon electrodes contain a significant number of electrolyte ions in the absence of any charging potential. This has important implications for the molecular mechanisms of supercapacitance, as charge can be stored by different ion adsorption/desorption processes. Crucially, we show how in situ NMR experiments can be used to quantitatively study and characterise the charging mechanism, with the experiments providing the most detailed picture of charge storage to date, offering the opportunity to design enhanced devices. Finally, an outlook for future directions for solid-state NMR in supercapacitor research is offered. PMID:26974032

  5. Modified Reference SPS with Solid State Transmitting Antenna

    NASA Technical Reports Server (NTRS)

    Woodcock, G. R.; Sperber, B. R.

    1980-01-01

    The development of solid state microwave power amplifiers for a solar power satellite transmitting antenna is discussed. State-of-the-art power-added efficiency, gain, and single device power of various microwave solid state devices are compared. The GaAs field effect transistors and the Si-bipolar transistors appear potentially feasible for solar power satellite use. The integration of solid state devices into antenna array elements is examined and issues concerning antenna integration and consequent satellite configurations are examined.

  6. A commercial hydrogen maser: Progress report

    NASA Technical Reports Server (NTRS)

    Dials, M. A.; Wert, L.

    1983-01-01

    The design of the new small passive hydrogen maser prototype and some anticipated design changes between the version reported and the commercial versions are discussed. Specifications of the commercial hydrogen maser and performance data of the prototype are given.

  7. Nanoprobes, nanostructured materials and solid state materials

    NASA Astrophysics Data System (ADS)

    Yin, Houping

    2005-07-01

    Novel templates have been developed to prepare nanostructured porous materials through nonsurfactant templated pathway. And new applications of these materials, such as drug delivery and molecular imprinting, have been explored. The relationship between template content and pore structure has been investigated. The composition and pore structures were studied in detail using IR, TGA, SEM, TEM, BET and XRD. The obtained mesoporous materials have tunable diameters in the range of 2--12 nm. Due to the many advantages of this nonsurfactant templated pathway, such as environment friendly and biocompatibility, controlled release of antibiotics in the nanoporous materials were studied. The in vitro release properties were found to depend on the silica structures which were well tuned by varying the template content. A controlled long-term release pattern of vancomycin was achieved when the template content was 30 wt% or lower. Nanoscale electrochemical probes with dimensions as small as 50 nm in diameter and 1--2 mum in length were fabricated using electron beam deposition on the apex of conventional micron size electrodes. The electroactive region was limited to the extreme tip of the nanoprobe by coating with an insulating polymer and re-opening of the coating at the extreme tip. The novel nanoelectrodes thus prepared were employed to probe neurons in mouse brain slice and the results suggest that the nanoprobes were capable of recording neuronal excitatory postsynaptic potential signals. Interesting solid state chemistry was found in oxygenated iron phthalocyanine. Their Mossbauer spectra show the formation of four oxygenated species apart from the unoxygenated parent compound. The oxygen-bridged compounds formed in the solid matrix bear no resemblance to the one formed by solution chemistry. Tentative assignment of species has been made with the help of Mossbauer and IR spectroscopy. An effort to modify aniline trimer for potential nanoelectronics applications and to

  8. Coincident Maser Emission in NGC 7538 IRS 1 from the (J,K) = (10,8) and (9,8) States of Para-Ammonia

    NASA Astrophysics Data System (ADS)

    Hoffman, Ian M.

    2013-01-01

    Using the Green Bank Telescope and the Very Large Array, we have detected the (J,K)=(10,8) and (9,8) ammonia lines from NGC 7538 for the first time. These are the first interferometric observations of the (10,8) transition of nonmetastable (J>K) para-ammonia (K not a multiple of three) in any source; in this case a synthesized beam of approximately 200 milliarcseconds. Both transitions show compact (< 100 milliarcseconds) and narrow (0.5 km/s) emission with high brightness temperature (> 104 K), indicative of maser amplification. Furthermore, the emission from both transitions occurs at the same velocity and at the same sky position within IRS 1, consistent with the conjecture that both transitions arise in the same volume of gas. We discuss the possible pumping of a maser for which population inversions can occur in adjacent "rungs" of value J within a "ladder" of value K. We also describe ongoing observations to constrain more fully the pumping and level populations elsewhere in the K=8 ladder. This work is supported by the Weaver Fund of Wittenberg University.

  9. Astrophysical masers; Proceedings of the Conference, Arlington, VA, Mar. 9-11, 1992

    NASA Technical Reports Server (NTRS)

    Clegg, Andrew W. (Editor); Nedoluha, Gerald E. (Editor)

    1993-01-01

    Various papers on astrophysical masers are presented. The general topics addressed include: theory, maser surveys, extragalactic masers, masers in star-forming regions (general), OH masers in star-forming regions, water masers in star-forming regions, methanol masers in star-forming regions, proper motions, scattering, variability, circumstellar masers (general), circumstellar OH masers, circumstellar water masers, circumstellar SiO masers, and solar system masers.

  10. Electron correlations in solid state physics

    SciTech Connect

    Freericks, J.K.

    1991-04-01

    Exactly solvable models of electron correlations in solid state physics are presented. These models include the spinless Falicov- Kimball model, the t-t{prime}-J model, and the Hubbard model. The spinless Falicov-Kimball model is analyzed in one-dimension. Perturbation theory and numerical techniques are employed to determine the phase diagram at zero temperature. A fractal structure is found where the ground-state changes (discontinuously) at each rational electron filling. The t-t{prime}-J model (strongly interacting limit of a Hubbard model) is studied on eight-site small clusters in the simple-cubic, body-centered-cubic, face-centered-cubic, and square lattices. Symmetry is used to simplify the problem and determine the exact many-body wavefunctions. Ground states are found that exhibit magnetic order or heavy-fermionic character. Attempts to extrapolate to the thermodynamic limit are also made. The Hubbard model is examined on an eight-site square-lattice cluster in the presence of and in the absence of a magnetic field'' that couples only to orbital motion. A new magnetic phase is discovered for the ordinary Hubbard model at half-filling. In the magnetic field'' case, it is found that the strongly frustrated Heisenberg model may be studied from adiabatic continuation of a tight-binding model (from weak to strong coupling) at one point. The full symmetries of the Hamiltonian are utilized to make the exact diagonalization feasibile. Finally, the presence of hidden'' extra symmetry for finite size clusters with periodic boundary conditions is analyzed for a variety of clusters. Moderately sized systems allow nonrigid transformations that map a lattice onto itself preserving its neighbor structure; similar operations are not present in smaller or larger systems. The additional symmetry requires particular representations of the space group to stick together explaining many puzzling degeneracies found in exact diagonalization studies.

  11. Lithium Polymer Electrolytes and Solid State NMR

    NASA Technical Reports Server (NTRS)

    Berkeley, Emily R.

    2004-01-01

    Research is being done at the Glenn Research Center (GRC) developing new kinds of batteries that do not depend on a solution. Currently, batteries use liquid electrolytes containing lithium. Problems with the liquid electrolyte are (1) solvents used can leak out of the battery, so larger, more restrictive, packages have to be made, inhibiting the diversity of application and decreasing the power density; (2) the liquid is incompatible with the lithium metal anode, so alternative, less efficient, anodes are required. The Materials Department at GRC has been working to synthesize polymer electrolytes that can replace the liquid electrolytes. The advantages are that polymer electrolytes do not have the potential to leak so they can be used for a variety of tasks, small or large, including in the space rover or in space suits. The polymers generated by Dr. Mary Ann Meador's group are in the form of rod -coil structures. The rod aspect gives the polymer structural integrity, while the coil makes it flexible. Lithium ions are used in these polymers because of their high mobility. The coils have repeating units of oxygen which stabilize the positive lithium by donating electron density. This aids in the movement of the lithium within the polymer, which contributes to higher conductivity. In addition to conductivity testing, these polymers are characterized using DSC, TGA, FTIR, and solid state NMR. Solid state NMR is used in classifying materials that are not soluble in solvents, such as polymers. The NMR spins the sample at a magic angle (54.7') allowing the significant peaks to emerge. Although solid state NMR is a helpful technique in determining bonding, the process of preparing the sample and tuning it properly are intricate jobs that require patience; especially since each run takes about six hours. The NMR allows for the advancement of polymer synthesis by showing if the expected results were achieved. Using the NMR, in addition to looking at polymers, allows for

  12. Solid-state Raman image amplification

    NASA Astrophysics Data System (ADS)

    Calmes, Lonnie Kirkland

    Amplification of low-light-level optical images is important for extending the range of lidar systems that image and detect objects in the atmosphere and underwater. The use of range-gating to produce images of particular range bins is also important in minimizing the image degradation due to light that is scattered backward from aerosols, smoke, or water along the imaging path. For practical lidar systems that must be operated within sight of unprotected observers, eye safety is of the utmost importance. This dissertation describes a new type of eye-safe, range-gated lidar sensing element based on Solid-state Raman Image Amplification (SSRIA) in a solid- state optical crystal. SSRIA can amplify low-level images in the eye-safe infrared at 1.556 μm with gains up to 106 with the addition of only quantum- limited noise. The high gains from SSRIA can compensate for low quantum efficiency detectors and can reduce the need for detector cooling. The range-gate of SSRIA is controlled by the pulsewidth of the pump laser and can be as short as 30-100 cm, using pump pulses of 2-6.7 nsec FWHM. A rate equation theoretical model is derived to help in the design of short pulsed Raman lasers. A theoretical model for the quantum noise properties of SSRIA is presented. SSRIA results in higher SNR images throughout a broad range of incident light levels, in contrast to the increasing noise factor with reduced gain in image intensified CCD's. A theoretical framework for the optical resolution of SSRIA is presented and it is shown that SSRIA can produce higher resolution than ICCD's. SSRIA is also superior in rejecting unwanted sunlight background, further increasing image SNR. Lastly, SSRIA can be combined with optical pre-filtering to perform optical image processing functions such as high-pass filtering and automatic target detection/recognition. The application of this technology to underwater imaging, called Marine Raman Image Amplification (MARIA) is also discussed. MARIA

  13. Solid state photomultiplier for astronomy, phase 2

    NASA Technical Reports Server (NTRS)

    Besser, P. J.; Hays, K. M.; Laviolette, R. A.

    1989-01-01

    Epitaxial layers with varying donor concentration profiles were grown on silicon substrate wafers using chemical vapor deposition (CVD) techniques, and solid state photomultiplier (SSPM) devices were fabricated from the wafers. Representative detectors were tested in a low background photon flux, low temperature environment to determine the device characteristics for comparison to NASA goals for astronomical applications. The SSPM temperatures varied between 6 and 11 K with background fluxes in the range from less than 5 x 10 to the 6th power to 10 to the 13th power photons/square cm per second at wavelengths of 3.2 and 20 cm. Measured parameters included quantum efficiency, dark count rate and bias current. Temperature for optimal performance is 10 K, the highest ever obtained for SSPMs. The devices exhibit a combination of the lowest dark current and highest quantum efficiency yet achieved. Experimental data were reduced, analyzed and used to generate recommendations for future studies. The background and present status of the microscopic theory of SSPM operation were reviewed and summarized. Present emphasis is on modeling of the avalanche process which is the basis for SSPM operation. Approaches to the solution of the Boltzmann transport equation are described and the treatment of electron scattering mechanisms is presented. The microscopic single-electron transport theory is ready to be implemented for large-scale computations.

  14. Radiation-Hardened Solid-State Drive

    NASA Technical Reports Server (NTRS)

    Sheldon, Douglas J.

    2010-01-01

    A method is provided for a radiationhardened (rad-hard) solid-state drive for space mission memory applications by combining rad-hard and commercial off-the-shelf (COTS) non-volatile memories (NVMs) into a hybrid architecture. The architecture is controlled by a rad-hard ASIC (application specific integrated circuit) or a FPGA (field programmable gate array). Specific error handling and data management protocols are developed for use in a rad-hard environment. The rad-hard memories are smaller in overall memory density, but are used to control and manage radiation-induced errors in the main, and much larger density, non-rad-hard COTS memory devices. Small amounts of rad-hard memory are used as error buffers and temporary caches for radiation-induced errors in the large COTS memories. The rad-hard ASIC/FPGA implements a variety of error-handling protocols to manage these radiation-induced errors. The large COTS memory is triplicated for protection, and CRC-based counters are calculated for sub-areas in each COTS NVM array. These counters are stored in the rad-hard non-volatile memory. Through monitoring, rewriting, regeneration, triplication, and long-term storage, radiation-induced errors in the large NV memory are managed. The rad-hard ASIC/FPGA also interfaces with the external computer buses.

  15. Introduction to cryogenic solid state cooling

    NASA Astrophysics Data System (ADS)

    Heremans, Joseph P.

    2016-05-01

    Thermoelectric (Peltier) coolers have historically not been used for cooling to temperatures much below 200 K, because of limitations with existing thermoelectric materials. There are many advantages to solid-state coolers: they have no moving parts, are compact, vibration-free, inherently durable, and scalable to low power levels. A significant drawback is their low coefficient of performance. The figure of merit, zT, is the materials characteristic that sets this efficiency in Peltier coolers. The zT decreases rapidly with temperature, roughly following a T7/2 law. However, new material developments have taken place in the last decade that have made it possible to reach zT>0.5 down to 50 K. Many new ideas have also been put forward that enable better ZT's and lower temperatures. This article reviews the difficulties associated with Peltier cooling at cryogenic temperatures, as an introduction to the following presentations and proceeding entries that will present solutions that have been developed since 2010.

  16. NASA developments in solid state power amplifiers

    NASA Technical Reports Server (NTRS)

    Leonard, Regis F.

    1990-01-01

    Over the last ten years, NASA has undertaken an extensive program aimed at development of solid state power amplifiers for space applications. Historically, the program may be divided into three phases. The first efforts were carried out in support of the advanced communications technology satellite (ACTS) program, which is developing an experimental version of a Ka-band commercial communications system. These first amplifiers attempted to use hybrid technology. The second phase was still targeted at ACTS frequencies, but concentrated on monolithic implementations, while the current, third phase, is a monolithic effort that focusses on frequencies appropriate for other NASA programs and stresses amplifier efficiency. The topics covered include: (1) 20 GHz hybrid amplifiers; (2) 20 GHz monolithic MESFET power amplifiers; (3) Texas Instruments' (TI) 20 GHz variable power amplifier; (4) TI 20 GHz high power amplifier; (5) high efficiency monolithic power amplifiers; (6) GHz high efficiency variable power amplifier; (7) TI 32 GHz monolithic power amplifier performance; (8) design goals for Hughes' 32 GHz variable power amplifier; and (9) performance goals for Hughes' pseudomorphic 60 GHz power amplifier.

  17. A novel solid state general illumination source

    NASA Astrophysics Data System (ADS)

    Nicol, David B.

    A novel solid state illumination source has been developed. A two terminal dual LED has been created with the ability to control the relative intensities of the two emission peaks by varying drive current. Doping profiles have been used to extend the dynamic range of the dual LED over other reported devices. Operation of the dual LEDs is explained as a function of drive current. In addition, novel use of phosphor mixtures allows the creation of a broadband spectral power distribution that can be varied using a dual LED as an excitation source. Combinations of phosphors that have varied excitation spectra provide the ability to selectively excite different phosphors with the different LED emission peaks. First and second generations of the two terminal dual LED and the phosphor combination are discussed. The final source has the ability to mimic the light of a blackbody radiator over a range of 3200 K - 5300 K. The development of a three terminal dual LED as a pump source was prohibited by the need for a III-nitride tunnel junction, that proved unattainable in the scope of this work. However, several novel doping schemes were investigated toward this end. Finally, a circadian light source has also been developed that can affect physiological changes in humans, and a light box for entrainment of circadian rhythms in rats has been built.

  18. Solid State Replacement of Rotating Mirror Cameras

    SciTech Connect

    Frank, A M; Bartolick, J M

    2006-08-25

    Rotating mirror cameras have been the mainstay of mega-frame per second imaging for decades. There is still no electronic camera that can match a film based rotary mirror camera for the combination of frame count, speed, resolution and dynamic range. The rotary mirror cameras are predominantly used in the range of 0.1 to 100 micro-seconds per frame, for 25 to more than a hundred frames. Electron tube gated cameras dominate the sub microsecond regime but are frame count limited. Video cameras are pushing into the microsecond regime but are resolution limited by the high data rates. An all solid state architecture, dubbed ''In-situ Storage Image Sensor'' or ''ISIS'', by Prof. Goji Etoh, has made its first appearance into the market and its evaluation is discussed. Recent work at Lawrence Livermore National Laboratory has concentrated both on evaluation of the presently available technologies and exploring the capabilities of the ISIS architecture. It is clear though there is presently no single chip camera that can simultaneously match the rotary mirror cameras, the ISIS architecture has the potential to approach their performance.

  19. Inorganic membranes and solid state sciences

    NASA Astrophysics Data System (ADS)

    Cot, Louis; Ayral, André; Durand, Jean; Guizard, Christian; Hovnanian, Nadine; Julbe, Anne; Larbot, André

    2000-05-01

    The latest developments in inorganic membranes are closely related to recent advances in solid state science. Sol-gel processing, plasma-enhanced chemical vapor deposition and hydrothermal synthesis are methods that can be used for inorganic membrane preparation. Innovative concepts from material science (templating effect, nanophase materials, growing of continuous zeolite layers, hybrid organic-inorganic materials) have been applied by our group to the preparation of inorganic membrane materials. Sol-gel-derived nanophase ceramic membranes are presented with current applications in nanofiltration and catalytic membrane reactors. Silica membranes with an ordered porosity, due to liquid crystal phase templating effect, are described with potential application in pervaporation. Defect-free and thermally stable zeolite membranes can be obtained through an original synthesis method, in which zeolite crystals are grown inside the pores of a support. Hybrid organic-inorganic materials with permselective properties for gas separation and facilitated transport of solutes in liquid media, have been successfully adapted to membrane applications. Potential membrane developments offered by CVD deposition techniques are also illustrated through several examples related to the preparation of purely inorganic and hybrid organic-inorganic membrane materials.

  20. Solid state replacement of rotating mirror cameras

    NASA Astrophysics Data System (ADS)

    Frank, Alan M.; Bartolick, Joseph M.

    2007-01-01

    Rotating mirror cameras have been the mainstay of mega-frame per second imaging for decades. There is still no electronic camera that can match a film based rotary mirror camera for the combination of frame count, speed, resolution and dynamic range. The rotary mirror cameras are predominantly used in the range of 0.1 to 100 micro-seconds per frame, for 25 to more than a hundred frames. Electron tube gated cameras dominate the sub microsecond regime but are frame count limited. Video cameras are pushing into the microsecond regime but are resolution limited by the high data rates. An all solid state architecture, dubbed 'In-situ Storage Image Sensor' or 'ISIS', by Prof. Goji Etoh has made its first appearance into the market and its evaluation is discussed. Recent work at Lawrence Livermore National Laboratory has concentrated both on evaluation of the presently available technologies and exploring the capabilities of the ISIS architecture. It is clear though there is presently no single chip camera that can simultaneously match the rotary mirror cameras, the ISIS architecture has the potential to approach their performance.

  1. SOLID-STATE CERAMIC LIGHTING PROJECT

    SciTech Connect

    Wayne D. Brown

    2003-06-01

    Meadow River Enterprises, Inc. (MRE) and the New York State College of Ceramics at Alfred University (NYSCC) received a DOE cooperative agreement award in September 1999 to develop an energy-efficient Solid-State Ceramic Lamp (SSCL). The program spanned a nominal two(2) year period ending in February of 2002. The federal contribution to the program totaled $1.6 million supporting approximately 78% of the program costs. The SSCL is a rugged electroluminescent lamp designed for outdoor applications. MRE has filed a provisional patent for this ''second generation'' technology and currently produces and markets blue-green phosphor SSCL devices. White phosphor SSCL devices are also available in prototype quantities. In addition to reducing energy consumption, the ceramic EL lamp offers several economic and societal advantages including lower lifecycle costs and reduced ''light pollution''. Significant further performance improvements are possible but will require a dramatic change in device physical construction related to the use of micro-powder materials and processes. The subject ''second-generation'' program spans a 27 month period and combines the materials and processing expertise of NYSCC, the manufacturing expertise of Meadow River Enterprises, and the phosphor development expertise of OSRAM Sylvania to develop an improved SSCL system. The development plan also includes important contributions by Marshall University (a part of the West Virginia University system). All primary development objectives have been achieved with the exception of improved phosphor powders. The performance characteristics of the first generation SSCL devices were carefully analyzed in year 1 and a second generation lamp was defined and optimized in year 2. The provisional patent was ''perfected'' through a comprehensive patent application filed in November 2002. Lamp efficiency was improved more than 2:1.

  2. Sample preparation for actinide solid state research

    NASA Astrophysics Data System (ADS)

    Spirlet, J. C.

    1982-09-01

    The actinide elements (5f elements) and their compounds constitute a very interesting group for solid state research. The electronic properties of the 5f elements show intermediate behavior between the well-understood, completely localized 4f system (lanthanides) and the 3d system (transition elements). The possibility of understanding some unexplained properties of the 3d elements through a systematic investigation of the electronic structures of the actinides considerably increased interest in samples with well-defined composition and structure and with well-known purity. In some cases, single crystals of low defect densities and high purity levels are needed to allow sophisticated investigations of physical properties. Actinide compounds are easily obtained at a high purity level by direct synthesis from pure elements using noncontaminating techniques. Examples of these techniques are the reaction of the actinide metal powder with the vapor of an oxidant in a sealed quartz ampoule, leviation melting on a water-cooled pedestal or melting in a Huking crucible. Actinide metals are produced by metallothermic reduction of commercially available oxides or carbides or by the van Arkel purification process. The metals are refined to the desired purity level by evaporation in vacuum for the more volatile elements (Ac, Pu, Am, Cm, Bk) and by the van Arkel process for the metals with low vapor pressure. Single crystals of actinide compounds have been grown by chemical vapor transport methods (oxides, chalcogenides), high temperature solution growth techniques (oxides), and pulling from the melt by the Czochralski method (oxides, intermetallics). Thin solid films have been prepared by vacuum evaporation or by focused ion-beam sputtering. The materials are analyzed for trace-level impurity content by inductively-coupled plasma spectroscopy, by spark source mass spectroscopy and by secondary-ion mass spectroscopy. The chemical composition of the compounds is determined by

  3. SOLID STATE ENERGY CONVERSION ALLIANCE DELPHI SOLID OXIDE FUEL CELL

    SciTech Connect

    Steven Shaffer; Sean Kelly; Subhasish Mukerjee; David Schumann; Gail Geiger; Kevin Keegan; John Noetzel; Larry Chick

    2003-12-08

    The objective of Phase I under this project is to develop a 5 kW Solid Oxide Fuel Cell power system for a range of fuels and applications. During Phase I, the following will be accomplished: Develop and demonstrate technology transfer efforts on a 5 kW stationary distributed power generation system that incorporates steam reforming of natural gas with the option of piped-in water (Demonstration System A). Initiate development of a 5 kW system for later mass-market automotive auxiliary power unit application, which will incorporate Catalytic Partial Oxidation (CPO) reforming of gasoline, with anode exhaust gas injected into an ultra-lean burn internal combustion engine. This technical progress report covers work performed by Delphi from January 1, 2003 to June 30, 2003, under Department of Energy Cooperative Agreement DE-FC-02NT41246. This report highlights technical results of the work performed under the following tasks: Task 1 System Design and Integration; Task 2 Solid Oxide Fuel Cell Stack Developments; Task 3 Reformer Developments; Task 4 Development of Balance of Plant (BOP) Components; Task 5 Manufacturing Development (Privately Funded); Task 6 System Fabrication; Task 7 System Testing; Task 8 Program Management; and Task 9 Stack Testing with Coal-Based Reformate.

  4. Analysis of NTSC's Timekeeping Hydrogen Masers

    NASA Astrophysics Data System (ADS)

    Song, H. J.; Dong, S. W.; Wang, Z. M.; Qu, L. L.; Jing, Y. J.; Li, W.

    2015-11-01

    In this article, the hydrogen masers were tested in NTSC (National Time Service Center) keeping time laboratory. In order to avoid the impact of larger noise of caesium atomic clocks, TA(k) or UTC(k) was not used as reference, and four hydrogen masers were mutually referred and tested. The frequency stabilities of hydrogen masers were analyzed by using four-cornered hat method, and the Allan standard deviation of single hydrogen maser was estimated in different sampling time. Then according to the characteristics of hydrogen masers, by removing the trend term, excluding outliers, and smoothing data with mathematical methods to separate the Gaussian noise of hydrogen masers, and finally through the normal Kolmogorov-Smirnov test, a single hydrogen maser's Gaussian noise has been estimated.

  5. Characteristics of advanced hydrogen maser frequency standards

    NASA Technical Reports Server (NTRS)

    Peters, H. E.

    1973-01-01

    In house research and development at Goddard Space Flight Center to provide advanced frequency and time standards for the most demanding applications is concentrated primarily in field operable atomic hydrogen masers. Some of the most important goals for the new maser designs have been improved long and short term stability, elimination of the need for auto tuning, increased maser oscillation level, improved hydrogen economy, increased operational life, minimization of operator control or monitoring, improvement in magnetic isolation or sensitivity, and reduction in size and weight. New design concepts which have been incorporated in these masers to achieve these goals are described. The basic maser assemblies and control systems have recently been completed; the masers are oscillating; and operational testing has begun. Data illustrating the improvements in maser performance was available and presented.

  6. Solid-state optical refrigeration to sub-100 Kelvin regime

    DOE PAGESBeta

    Melgaard, Seth D.; Albrecht, Alexander R.; Hehlen, Markus P.; Sheik-Bahae, Mansoor

    2016-02-05

    We report that since the first demonstration of net cooling twenty years ago, optical refrigeration of solids has progressed to outperform all other solid-state cooling processes. It has become the first and only solid-state refrigerator capable of reaching cryogenic temperatures, and now the first solid-state cooling below 100 K. Such substantial progress required a multi-disciplinary approach of pump laser absorption enhancement, material characterization and purification, and thermal management. Here we present the culmination of two decades of progress, the record cooling to ≈91K from room temperature.

  7. Solid-state optical refrigeration to sub-100 Kelvin regime

    NASA Astrophysics Data System (ADS)

    Melgaard, Seth D.; Albrecht, Alexander R.; Hehlen, Markus P.; Sheik-Bahae, Mansoor

    2016-02-01

    Since the first demonstration of net cooling twenty years ago, optical refrigeration of solids has progressed to outperform all other solid-state cooling processes. It has become the first and only solid-state refrigerator capable of reaching cryogenic temperatures, and now the first solid-state cooling below 100 K. Such substantial progress required a multi-disciplinary approach of pump laser absorption enhancement, material characterization and purification, and thermal management. Here we present the culmination of two decades of progress, the record cooling to ≈ 91 K from room temperature.

  8. Solid-state optical refrigeration to sub-100 Kelvin regime.

    PubMed

    Melgaard, Seth D; Albrecht, Alexander R; Hehlen, Markus P; Sheik-Bahae, Mansoor

    2016-01-01

    Since the first demonstration of net cooling twenty years ago, optical refrigeration of solids has progressed to outperform all other solid-state cooling processes. It has become the first and only solid-state refrigerator capable of reaching cryogenic temperatures, and now the first solid-state cooling below 100 K. Such substantial progress required a multi-disciplinary approach of pump laser absorption enhancement, material characterization and purification, and thermal management. Here we present the culmination of two decades of progress, the record cooling to ≈ 91 K from room temperature. PMID:26847703

  9. Solid-state optical refrigeration to sub-100 Kelvin regime

    PubMed Central

    Melgaard, Seth D.; Albrecht, Alexander R.; Hehlen, Markus P.; Sheik-Bahae, Mansoor

    2016-01-01

    Since the first demonstration of net cooling twenty years ago, optical refrigeration of solids has progressed to outperform all other solid-state cooling processes. It has become the first and only solid-state refrigerator capable of reaching cryogenic temperatures, and now the first solid-state cooling below 100 K. Such substantial progress required a multi-disciplinary approach of pump laser absorption enhancement, material characterization and purification, and thermal management. Here we present the culmination of two decades of progress, the record cooling to ≈ 91 K from room temperature. PMID:26847703

  10. Advanced mid-IR Solid-State Laser Developments

    NASA Technical Reports Server (NTRS)

    Yu, Jirong

    2005-01-01

    This paper reviews the state-of-the-art 2-micron solid-state laser developments. A world record one-Joule-per-pulse energy laser system and an advanced thermal management with fully conductive cooled laser technique are discussed

  11. General purpose solid state camera for SERTS

    NASA Astrophysics Data System (ADS)

    Payne, Leslie J.; Haas, J. Patrick

    1996-11-01

    The Laboratory for Astronomy and Solar Physics at Goddard Space Flight Center uses a variety of CCD's and other solid state imaging sensors for its instrumentation programs. Traditionally, custom camera systems are built around the imaging device to optimize the circuitry for the particular sensor. This usually produces a camera that is small, uses little power and is elegant. Although these are desirable characteristics, this approach is also expensive and time consuming. An alternative approach is to design a `universal' camera that is easily customized to meet specific mission requirements. This is the approach our team used for SERTS. The camera design used to support the SERTS mission is a general purpose camera design that is derived from an existing camera on the SOHO spacecraft. This camera is designed to be rugged, modest in power requirements and flexible. The base design of the camera supports quadrant CCD devices with up to 4 phases. Imaging devices with simpler architectures are in general supportable. The basic camera is comprised of a main electronics box which performs all timing generation, voltage level control, data processing and compression. A second unit, placed close to the detector head, is responsible for driving the image device control electrodes and amplifying the multichannel detector video. Programmable high voltage units are used for the single stage MCP type intensifier. The detector head is customized for each sensor type supported. Auxiliary equipment includes a frame buffer that works either as a multi-frame storage unit or as a photon counting accumulation unit. This unit also performs interface buffering so that the camera may appear as a piece of GPIB instrumentation.

  12. Solid State Molecular Reactors in Space

    NASA Astrophysics Data System (ADS)

    Maurette, M.

    2011-03-01

    Lunar minerals and impact glasses, convert the polyatomic beam of solar wind (SW) ions into a flux of small molecules (e.g., H2, N2, H2O, CO, CO2, CH4, C2H4, C2H6, HCN, metal carbides and deuterides, etc.). They thus behave as "Solid State Molecular Reactors". Moreover, ~100-200 μm size micrometeoroids (μMs) have also been exposed to the SW in the zodiacal cloud, before being captured by the Earth and recovered as Antarctic micrometeorites. They are mostly composed of a PAH-rich hydrous-carbonaceous material, which amplifies their power as molecular reactors. In particular, during the first ~200 Myr of the post-lunar period, about 75% of the μMs have been melted and/or volatilized upon atmospheric entry. The release of their volatile species triggered a cosmic volcanism around the mesopause that ruled the formation of the early Earth's atmosphere and climate. Furthermore, a fraction of the μMs that survive unmelted upon atmospheric entry did settle on the proto-oceans floors. Upon further burial in sediments their constituent PAH-rich kerogen was cracked into abiotic oil, which generated giant oil slicks that fed prebiotic chemistry. Many stars, of all ages and types, are embedded into a secondary debris-disk loaded with ion implanted μMs. Some of them are expelled to the interstellar medium (ISM) where they behave first as "dormant-invisible" molecular reactors, until they became reactivated by various processes to synthesize interstellar molecules. This short paper only focus on some highlights of this research dealing with the synthesis of important interstellar molecules, including the most abundant ones (H2 and CO) and H2O, HCN and PAHs, all involved in prebiotic chemistry.

  13. SOLID STATE ENERGY CONVERSION ALLIANCE DELPHI SOLID OXIDE FUEL CELL

    SciTech Connect

    Steven Shaffer; Sean Kelly; Subhasish Mukerjee; David Schumann; Gail Geiger; Kevin Keegan; Larry Chick

    2004-05-07

    The objective of this project is to develop a 5 kW Solid Oxide Fuel Cell power system for a range of fuels and applications. During Phase I, the following will be accomplished: Develop and demonstrate technology transfer efforts on a 5 kW stationary distributed power generation system that incorporates steam reforming of natural gas with the option of piped-in water (Demonstration System A). Initiate development of a 5 kW system for later mass-market automotive auxiliary power unit application, which will incorporate Catalytic Partial Oxidation (CPO) reforming of gasoline, with anode exhaust gas injected into an ultra-lean burn internal combustion engine. This technical progress report covers work performed by Delphi from July 1, 2003 to December 31, 2003, under Department of Energy Cooperative Agreement DE-FC-02NT41246. This report highlights technical results of the work performed under the following tasks: Task 1 System Design and Integration; Task 2 Solid Oxide Fuel Cell Stack Developments; Task 3 Reformer Developments; Task 4 Development of Balance of Plant (BOP) Components; Task 5 Manufacturing Development (Privately Funded); Task 6 System Fabrication; Task 7 System Testing; Task 8 Program Management; Task 9 Stack Testing with Coal-Based Reformate; and Task 10 Technology Transfer from SECA CORE Technology Program. In this reporting period, unless otherwise noted Task 6--System Fabrication and Task 7--System Testing will be reported within Task 1 System Design and Integration. Task 8--Program Management, Task 9--Stack Testing with Coal Based Reformate, and Task 10--Technology Transfer from SECA CORE Technology Program will be reported on in the Executive Summary section of this report.

  14. Solid state device technology for Solar Power Satellite

    NASA Technical Reports Server (NTRS)

    Weir, D. G.

    1980-01-01

    The feasibility of using solid state elements in the solar power satellite transmitter system is addressed. Recommendations are given concerning device types, the antenna modules, and the overall antenna system. The development of a solid state amplifier based on GaAs field effect transistor devices is also described.

  15. Metal speciation of phosphorus derived from solid state spectroscopic analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Significant improvements have been made in the last decade towards understanding metal species associated with manure P using XANES and solid-state 31P NMR techniques. Both solid-state techniques are particularly sensitive to inorganic forms of P associated with metals in manure samples. In unamen...

  16. Solid State Energy Conversion Alliance Delphi SOFC

    SciTech Connect

    Steven Shaffer; Gary Blake; Sean Kelly; Subhasish Mukerjee; Karl Haltiner; Larry Chick; David Schumann; Jeff Weissman; Gail Geiger; Ralphi Dellarocco

    2006-12-31

    The following report details the results under the DOE SECA program for the period July 2006 through December 2006. Developments pertain to the development of a 3 to 5 kW Solid Oxide Fuel Cell power system for a range of fuels and applications. This report details technical results of the work performed under the following tasks for the SOFC Power System: Task 1 SOFC System Development; Task 2 Solid Oxide Fuel Cell Stack Developments; Task 3 Reformer Developments; Task 4 Development of Balance of Plant Components; Task 5 Project Management; and Task 6 System Modeling & Cell Evaluation for High Efficiency Coal-Based Solid Oxide Fuel Cell Gas Turbine Hybrid System.

  17. Solid State Joining of Dissimilar Titanium Alloys

    NASA Astrophysics Data System (ADS)

    Morton, Todd W.

    Solid state joining of titanium via friction stir welding and diffusion bonding have emerged as enablers of efficient monolithic structural designs by the eliminations fasteners for the aerospace industry. As design complexity and service demands increase, the need for joints of dissimilar alloys has emerged. Complex thermomechanical conditions in friction stir weld joints and high temperature deformation behavior differences between alloys used in dissimilar joints gives rise to a highly variable flow pattern within a stir zone. Experiments performed welding Ti-6Al-4V to beta21S show that mechanical intermixing of the two alloys is the primary mechanism for the generation of the localized chemistry and microstructure, the magnitude of which can be directly related to pin rotation and travel speed weld parameters. Mechanical mixing of the two alloys is heavily influenced by strain rate softening phenomena, and can be used to manipulate weld nugget structure by switching which alloy is subjected to the advancing side of the pin. Turbulent mixing of a weld nugget and a significant reduction in defects and weld forces are observed when the beta21S is put on the advancing side of the weld where higher strain rates are present. Chemical diffusion driven by the heat of weld parameters is characterized using energy dispersive x-ray spectroscopy (EDS) and is shown to be a secondary process responsible for generating short-range chemical gradients that lead to a gradient of alpha particle structures. Diffusion calculations are inconsistent with an assumption of steady-state diffusion and show that material interfaces in the weld nugget evolve through the break-down of turbulent interface features generated by material flows. A high degree of recrystallization is seen throughout the welds, with unique, hybrid chemistry grains that are generated at material interfaces in the weld nugget that help to unify the crystal structure of dissimilar alloys. The degree of

  18. Preliminary field evaluation of solid state cameras for security applications

    SciTech Connect

    Murray, D.W.

    1987-07-01

    Recent developments in solid state imager technology have resulted in a series of compact, lightweight, all-solid-state closed circuit television (CCTV) cameras. Although it is widely known that the various solid state cameras have less light sensitivity and lower resolution than their vacuum tube counterparts, the potential for having a much longer Mean Time Between Failure (MTBF) for the all-solid-state cameras is generating considerable interest within the security community. Questions have been raised as to whether the newest and best of the solid state cameras are a viable alternative to the high maintenance vacuum tube cameras in exterior security applications. To help answer these questions, a series of tests were performed by Sandia National Laboratories at various test sites and under several lighting conditions. The results of these tests as well as a description of the test equipment, test sites, and procedures are presented in this report.

  19. The Galileo Solid-State Imaging experiment

    USGS Publications Warehouse

    Belton, M.J.S.; Klaasen, K.P.; Clary, M.C.; Anderson, J.L.; Anger, C.D.; Carr, M.H.; Chapman, C.R.; Davies, M.E.; Greeley, R.; Anderson, D.; Bolef, L.K.; Townsend, T.E.; Greenberg, R.; Head, J. W., III; Neukum, G.; Pilcher, C.B.; Veverka, J.; Gierasch, P.J.; Fanale, F.P.; Ingersoll, A.P.; Masursky, H.; Morrison, D.; Pollack, James B.

    1992-01-01

    The Solid State Imaging (SSI) experiment on the Galileo Orbiter spacecraft utilizes a high-resolution (1500 mm focal length) television camera with an 800 ?? 800 pixel virtual-phase, charge-coupled detector. It is designed to return images of Jupiter and its satellites that are characterized by a combination of sensitivity levels, spatial resolution, geometric fiedelity, and spectral range unmatched by imaging data obtained previously. The spectral range extends from approximately 375 to 1100 nm and only in the near ultra-violet region (??? 350 nm) is the spectral coverage reduced from previous missions. The camera is approximately 100 times more sensitive than those used in the Voyager mission, and, because of the nature of the satellite encounters, will produce images with approximately 100 times the ground resolution (i.e., ??? 50 m lp-1) on the Galilean satellites. We describe aspects of the detector including its sensitivity to energetic particle radiation and how the requirements for a large full-well capacity and long-term stability in operating voltages led to the choice of the virtual phase chip. The F/8.5 camera system can reach point sources of V(mag) ??? 11 with S/N ??? 10 and extended sources with surface brightness as low as 20 kR in its highest gain state and longest exposure mode. We describe the performance of the system as determined by ground calibration and the improvements that have been made to the telescope (same basic catadioptric design that was used in Mariner 10 and the Voyager high-resolution cameras) to reduce the scattered light reaching the detector. The images are linearly digitized 8-bits deep and, after flat-fielding, are cosmetically clean. Information 'preserving' and 'non-preserving' on-board data compression capabilities are outlined. A special "summation" mode, designed for use deep in the Jovian radiation belts, near Io, is also described. The detector is 'preflashed' before each exposure to ensure the photometric linearity

  20. Solid-State NMR Studies of Amyloid Fibril Structure

    NASA Astrophysics Data System (ADS)

    Tycko, Robert

    2011-05-01

    Current interest in amyloid fibrils stems from their involvement in neurodegenerative and other diseases and from their role as an alternative structural state for many peptides and proteins. Solid-state nuclear magnetic resonance (NMR) methods have the unique capability of providing detailed structural constraints for amyloid fibrils, sufficient for the development of full molecular models. In this article, recent progress in the application of solid-state NMR to fibrils associated with Alzheimer's disease, prion fibrils, and related systems is reviewed, along with relevant developments in solid-state NMR techniques and technology.

  1. Solid State NMR Studies of Amyloid Fibril Structure

    PubMed Central

    Tycko, Robert

    2011-01-01

    Current interest in amyloid fibrils stems from their involvement in neurodegenerative and other diseases and from their role as an alternative structural state for many peptides and proteins. Solid state NMR methods have the unique capability of providing detailed structural constraints for amyloid fibrils, sufficient for the development of full molecular models. In this article, recent progress in the application of solid state NMR to fibrils associated with Alzheimer’s disease, prion fibrils, and related systems is reviewed, along with relevant developments in solid state NMR techniques and technology. PMID:21219138

  2. Solid State Ionic Materials - Proceedings of the 4th Asian Conference on Solid State Ionics

    NASA Astrophysics Data System (ADS)

    Chowdari, B. V. R.; Yahaya, M.; Talib, I. A.; Salleh, M. M.

    1994-07-01

    The Table of Contents for the full book PDF is as follows: * Preface * I. INVITED PAPERS * Diffusion of Cations and Anions in Solid Electrolytes * Silver Ion Conductors in the Crystalline State * NMR Studies of Superionic Conductors * Hall Effect and Thermoelectric Power in High Tc Hg-Ba-Ca-Cu-O Ceramics * Solid Electrolyte Materials Prepared by Sol-Gel Chemistry * Preparation of Proton-Conducting Gel Films and their Application to Electrochromic Devices * Thin Film Fuel Cells * Zirconia based Solid Oxide Ion Conductors in Solid Oxide Fuel Cells * The Influence of Anion Substitution on Some Phosphate-based Ion Conducting Glasses * Lithium Intercalation in Carbon Electrodes and its Relevance in Rocking Chair Batteries * Chemical Sensors using Proton Conducting Ceramics * NMR/NQR Studies of Y-Ba-Cu-O Superconductors * Silver Molybdate Glasses and Battery Systems * New Highly Conducting Polymer Ionics and their Application in Electrochemical Devices * Study of Li Electrokinetics on Oligomeric Electrolytes using Microelectrodes * Calculation of Conductivity for Mixed-Phase Electrolytes PEO-MX-Immiscible Additive by Means of Effective Medium Theory * II. CONTRIBUTED PAPERS * Phase Relationship and Electrical Conductivity of Sr-V-O System with Vanadium Suboxide * Amorphous Li+ Ionic Conductors in Li2SO4-Li2O-P2O5 System * Fast Ion Transport in KCl-Al2O3 Composites * The Effect of the Second Phase Precipitation on the Ionic Conductivity of Zr0.85Mg0.15O1.85 * Conductivity Measurements and Phase Relationships in CaCl2-CaHCl Solid Electrolyte * Relationships Between Crystal Structure and Sodium Ion Conductivity in Na7Fe4(AsO4)6 and Na3Al2(AsO4)3 * Electrical Conductivity and Solubility Limit of Ti4+ Ion in Na1+x TiyZr2-ySixP3-xO12 System * Study on Sodium Fast Ion Conductors of Na1+3xAlxTi2-xSi2xP3-2xO12 System * Influences of Zirconia on the Properties of β''-Alumina Ceramics * Decay of Luminescence from Cr3+ Ions in β-Alumina * Lithium Ion Conductivity in the Li4XO4-Li2

  3. Solid-state impact-ionization multiplier

    NASA Astrophysics Data System (ADS)

    Lee, Hong-Wei

    This dissertation presents an innovative solid-state current amplifier based on impact-ionization. Unlike avalanche photodetectors which use the same amplification principle, this device can be integrated with any external current source. A discrete amplifier was built on a silicon surface using standard CMOS fabrication processes including lithography, oxidation, ion implantation, diffusion, chemical wet etching, metal deposition, annealing, and rapid thermal processing. Testing was performed by connecting the device to a silicon photodiode, indium-gallium-arsenide photodiodes, and a function generator to demonstrate its compatibility with arbitrary current sources. Current gains above 100 along with pre-amplified leakage currents of less than 10 nA were measured. This amplifier can also be cascaded to achieve very high gains similar to the photomultiplier tube but with much smaller size and no vacuum environment required. Testing was done by amplifying the output signal from an external silicon photodiode. Current gains over 600 were measured when two amplifying devices were cascaded. Additionally, the gain saturation phenomenon of the amplifier due to the space-charge effect is investigated. The measured gain saturation is observed to match very well with the theoretical based predictions. We also present a design rule for obtaining high current gain from the cascaded structure without experiencing gain saturation. Initial bandwidth of the SIM when connected to a silicon photodiode was measured to be about 300 kHz. As we replace the photodiode by a function generator, the bandwidth improved to 450 kHz which is the frequency limit of the system. These results were made on the first generation of SIM devices. We discovered that the space-charge resistance Rsc plays a significant role in determining frequency response. In future generations of the device, we can begin with optimizing the device geometry to reduce this resistance. Also, we can reduce the size of the

  4. Accurate water maser positions from HOPS

    NASA Astrophysics Data System (ADS)

    Walsh, Andrew J.; Purcell, Cormac R.; Longmore, Steven N.; Breen, Shari L.; Green, James A.; Harvey-Smith, Lisa; Jordan, Christopher H.; Macpherson, Christopher

    2014-08-01

    We report on high spatial resolution water maser observations, using the Australia Telescope Compact Array, towards water maser sites previously identified in the H2O southern Galactic Plane Survey (HOPS). Of the 540 masers identified in the single-dish observations of Walsh et al., we detect emission in all but 31 fields. We report on 2790 spectral features (maser spots), with brightnesses ranging from 0.06 to 576 Jy and with velocities ranging from -238.5 to +300.5 km s-1. These spectral features are grouped into 631 maser sites. We have compared the positions of these sites to the literature to associate the sites with astrophysical objects. We identify 433 (69 per cent) with star formation, 121 (19 per cent) with evolved stars and 77 (12 per cent) as unknown. We find that maser sites associated with evolved stars tend to have more maser spots and have smaller angular sizes than those associated with star formation. We present evidence that maser sites associated with evolved stars show an increased likelihood of having a velocity range between 15 and 35 km s-1 compared to other maser sites. Of the 31 non-detections, we conclude they were not detected due to intrinsic variability and confirm previous results showing that such variable masers tend to be weaker and have simpler spectra with fewer peaks.

  5. Modeling solid-state transformations occurring in dissolution testing.

    PubMed

    Laaksonen, Timo; Aaltonen, Jaakko

    2013-04-15

    Changes in the solid-state form can occur during dissolution testing of drugs. This can often complicate interpretation of results. Additionally, there can be several mechanisms through which such a change proceeds, e.g. solvent-mediated transformation or crystal growth within the drug material itself. Here, a mathematical model was constructed to study the dissolution testing of a material, which undergoes such changes. The model consisted of two processes: the recrystallization of the drug from a supersaturated liquid state caused by the dissolution of the more soluble solid form and the crystal growth of the stable solid form at the surface of the drug formulation. Comparison to experimental data on theophylline dissolution showed that the results obtained with the model matched real solid-state changes and that it was able to distinguish between cases where the transformation was controlled either by solvent-mediated crystallization or solid-state crystal growth. PMID:23506958

  6. Cavity approach to the random solid state.

    PubMed

    Mao, Xiaoming; Goldbart, Paul M; Mézard, Marc; Weigt, Martin

    2005-09-30

    The cavity approach is used to address the physical properties of random solids in equilibrium. Particular attention is paid to the fraction of localized particles and the distribution of localization lengths characterizing their thermal motion. This approach is of relevance to a wide class of random solids, including rubbery media (formed via the vulcanization of polymer fluids) and chemical gels (formed by the random covalent bonding of fluids of atoms or small molecules). The cavity approach confirms results that have been obtained previously via replica mean-field theory, doing so in a way that sheds new light on their physical origin. PMID:16241698

  7. Solid-state magnetic resonance spectroscopy of fullerenes

    SciTech Connect

    Tycko, R.; Haddon, R.C.; Dabbagh, G.; Glarum, S.H.; Douglass, D.C.; Mujsce, A.M. )

    1991-01-24

    The authors report solid-state {sup 13}C NMR measurements on powder samples of C{sub 60} and of a mixture of C{sub 60} and C{sub 70}. The NMR results show that, at 296 K, C{sub 60} molecules rotate rapidly and isotropically in the solid state, while C{sub 70} molecules rotate somewhat more anisotropically. These results are consistent with the proposed spherical geometry of C{sub 60} and prolate spheroidal geometry of C{sub 70}. The rotational correlation time of C{sub 60} molecules in the solid state becomes greater than 50 {mu}s at about 100 K.

  8. Diode laser-pumped solid-state lasers

    NASA Technical Reports Server (NTRS)

    Fan, Tso Yee; Byer, Robert L.

    1988-01-01

    Recently, interest in diode laser-pumped solid-state lasers has increased due to their advantages over flashlamp-pumped solid-state lasers. A historical overview is presented of semiconductor diode-pumped solid-state lasers beginning with work in the early 1960s and continuing through recent work on wavelength extension of these devices by laser operation on new transitions. Modeling of these devices by rate equations to obtain expressions for threshold, slope efficiency, and figures of merit is also given.

  9. The solid state detector technology for picosecond laser ranging

    NASA Technical Reports Server (NTRS)

    Prochazka, Ivan

    1993-01-01

    We developed an all solid state laser ranging detector technology, which makes the goal of millimeter accuracy achievable. Our design and construction philosophy is to combine the techniques of single photon ranging, ultrashort laser pulses, and fast fixed threshold discrimination while avoiding any analog signal processing within the laser ranging chain. The all solid state laser ranging detector package consists of the START detector and the STOP solid state photon counting module. Both the detectors are working in an optically triggered avalanche switching regime. The optical signal is triggering an avalanche current buildup which results in the generation of a uniform, fast risetime output pulse.

  10. Solid-State Metalloproteins-An Alternative to Immobilisation.

    PubMed

    Rapson, Trevor D

    2016-01-01

    This commentary outlines a protein engineering approach as an alternative to immobilisation developed in our laboratory. We use a recombinant silk protein into which metal active sites can be incorporated to produce solid-state metalloprotein materials. The silk protein directly coordinates to the metal centres providing control over their reactivity akin to that seen in naturally occurring metalloproteins. These solid-state materials are remarkably stable at a range of temperatures and different solvent conditions. I discuss the genesis of this approach and highlight areas where such solid-state materials could find application. PMID:27428936

  11. Fabrication and characterization of solid-state, conducting polymer actuators

    SciTech Connect

    Xie, J.; Sansinena, J. M.; Gao, J.; Wang, H. L.

    2004-01-01

    We report here the fabrication and characterization of solid-state, conducting polymer actuators. The electrochemical activity of polyaniline (PANI) thin film coated with solid-state polyelectrolyte is very similar to the polyaniline thin film in an aqueous solution. The solid-state actuator is adhere to a lever arm of an force transducer and the force generation is measured in real time. The force generated by the actuator is found to be length dependent. However, the overall torques generated by the actuators with different lengths remains essentially the same. The effect of stimulation signals such as voltage, current, on the bending angle and displacement is also studied using square wave potential.

  12. Solar Power Satellite (SPS) solid-state antenna power combiner

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A low loss power-combining microstrip antenna suitable for solid state solar power satellite (SPS) application was developed. A unique approach for performing both the combining and radiating function in a single cavity-type circuit was verified, representing substantial refinements over previous demonstration models in terms of detailed geometry to obtain good matching and adequate bandwidth at the design frequency. The combiner circuit was designed, built, and tested and the overall results support the view that the solid state power-combining antenna approach is a viable candidate for a solid state SPS antenna building block.

  13. Interstellar A-type methanol masers

    NASA Astrophysics Data System (ADS)

    Zeng, Q.; Lou, G. F.

    1990-02-01

    The formation conditions for A-type methanol masers are discussed. The correlation between A-type masers and external radiation fields is determined, with emphasis on the energy levels of A-type methanol and brightness temperature. Radiative transfer equations and statistical equilibrium are solved using a large velocity gradient model and the escape probability model. It is demonstrated that the 9(2)-10(1)A+ emission in W3(OH) and 7(0)-6(1)A in SgrB2 are masers, as discovered previously. The formation of the first type of masers requires pumping from an external radiation field, while the second type might be excited in the absence of an external radiation field. It is also pointed out that according to calculations there are A-type maser series similar to E-type methanol maser series of J2-J1E.

  14. High Extraction Phosphors for Solid State Lighting

    SciTech Connect

    Summers, Chris; Menkara, Hisham; Wagner, Brent

    2011-09-01

    We have developed high-index, high efficiency bulk luminescent materials and novel nano-sized phosphors for improved solid-state white LED lamps. These advances can potentially contribute to reducing the loss in luminous efficiencies due to scattering, re-absorption, and thermal quenching. The bulk and nanostructured luminescent materials investigated are index matched to GaN and have broad and size-tunable absorption bands, size and impurity tuned emission bands, size-driven elimination of scattering effects, and a separation between absorption and emission bands. These innovations were accomplished through the use of novel synthesis techniques suitable for high volume production for LED lamp applications. The program produced a full-color set of high quantum yield phosphors with high chemical stability. In the bulk phosphor study, the ZnSeS:Cu,Ag phosphor was optimized to achieve >91% efficiency using erbium (Er) and other activators as sensitizers. Detailed analysis of temperature quenching effects on a large number of ZnSeS:Cu,Ag,X and strontium- and calcium-thiogallate phosphors lead to a breakthrough in the understanding of the anti-quenching behavior and a physical bandgap model was developed of this phenomena. In a follow up to this study, optimized phosphor blends for high efficiency and color performance were developed and demonstrated a 2-component phosphor system with good white chromaticity, color temperature, and high color rendering. By extending the protocols of quantum dot synthesis, large nanocrystals, greater than 20 nm in diameter were synthesized and exhibited bulk-like behavior and blue light absorption. The optimization of ZnSe:Mn nanophosphors achieved ~85% QE The limitations of core-shell nanocrystal systems were addressed by investigating alternative deltadoped structures. To address the manufacturability of these systems, a one-pot manufacturing protocol was developed for ZnSe:Mn nanophosphors. To enhance the stability of these material

  15. Chemical reactivity in solid-state pharmaceuticals: formulation implications.

    PubMed

    Byrn, S R; Xu, W; Newman, A W

    2001-05-16

    Solid-state reactions that occur in drug substances and formulations include solid-state phase transformations, dehydration/desolvation, and chemical reactions. Chemical reactivity is the focus of this chapter. Of particular interest are cases where the drug-substance may be unstable or react with excipients in the formulation. Water absorption can enhance molecular mobility of solids and lead to solid-state reactivity. Mobility can be measured using various methods including glass transition (T(g)) measurements, solid-state NMR, and X-ray crystallography. Solid-state reactions of drug substances can include oxidation, cyclization, hydrolysis, and deamidation. Oxidation studies of vitamin A, peptides (DL-Ala-DL-Met, N-formyl-Met-Leu-Phe methyl ester, and Met-enkaphalin acetate salt), and steroids (hydrocortisone and prednisolone derivatives) are discussed. Cyclization reactions of crystalline and amorphous angiotensin-converting enzyme (ACE) inhibitors (spirapril hydrochloride, quinapril hydrochloride, and moexipril) are presented which investigate mobility and chemical reactivity. Examples of drug-excipient interactions, such as transacylation, the Maillard browning reaction, and acid base reactions are discussed for a variety of compounds including aspirin, fluoxitine, and ibuprofen. Once solid-state reactions are understood in a pharmaceutical system, the necessary steps can be taken to prevent reactivity and improve the stability of drug substances and products. PMID:11325479

  16. Handel's Maser-Soliton Theory of ball lightning: The creation of stable three-dimensional cavitons by an atmospheric maser within an open resonator

    NASA Astrophysics Data System (ADS)

    Carlson, Glenn Andrew

    This dissertation develops details of Handel's Maser-Soliton Theory of ball lightning. The atmosphere between a thundercloud and the Earth's surface is modeled as an idealized stable open resonator with water vapor as the active medium and the thundercloud and Earth's surface as reflecting surfaces. The stable resonator generates a maser beam that narrows to the beam waist at the Earth's surface, which is assumed to be planar. Two candidate rotational transitions are identified within the ν1ν 2ν3 = 010 vibrational band of water having wavelengths of 13.9 cm and 1.12 cm, and relevant spectroscopic parameters are retrieved from the HITRAN 2008 molecular spectroscopic database. The maser is modeled as a continuously pumped four-level maser that includes the effects of nonradiative relaxation due to molecular collisions and of microwave absorption in atmospheric oxygen. Since maser spiking is highly unlikely to occur due to the high rate of collisional relaxation at normal atmospheric pressure, the electrical breakdown of air must be achieved by the steady state output of the atmospheric maser. A parametric analysis is performed to relate the size of the atmospheric maser to the pumping rate needed to create a steady state population inversion sufficient to generate maser radiation intense enough at the beam waist to result in the electrical breakdown of air. The analysis suggests that electric field intensities at the beam waist sufficient to cause electrical breakdown of air could only be created through huge pumping rates (˜105 to 107 times the critical pumping rate) and only for the most highly curved clouds (g ≈ 0) that give the narrowest beam waists.

  17. On the classification and list of transitions of methanol masers

    NASA Astrophysics Data System (ADS)

    Sobolev, A. M.

    A classification of methanol masers according to the type of maser sources is suggested. The list of candidates to be methanol masering transitions is compiled on the basis of general regularities analysis combined with results of statistical equilibrium calculations.

  18. Angular wander measurements of maser clusters

    NASA Astrophysics Data System (ADS)

    Mutel, Robert L.

    Angular wander measurements of the relative positions of closely spaced maser features provides a powerful probe of interstellar turbulence associated with regions of star formation. Differential angular wander is easily measured in a maser complex and can strongly distinguish between shallow and steep power-law turbulence. The best candidates for such measurements appear to be the 6 and 12 GHz type II methanol masers.

  19. Solid State Ionic Materials - Proceedings of the 4th Asian Conference on Solid State Ionics

    NASA Astrophysics Data System (ADS)

    Chowdari, B. V. R.; Yahaya, M.; Talib, I. A.; Salleh, M. M.

    1994-07-01

    The Table of Contents for the full book PDF is as follows: * Preface * I. INVITED PAPERS * Diffusion of Cations and Anions in Solid Electrolytes * Silver Ion Conductors in the Crystalline State * NMR Studies of Superionic Conductors * Hall Effect and Thermoelectric Power in High Tc Hg-Ba-Ca-Cu-O Ceramics * Solid Electrolyte Materials Prepared by Sol-Gel Chemistry * Preparation of Proton-Conducting Gel Films and their Application to Electrochromic Devices * Thin Film Fuel Cells * Zirconia based Solid Oxide Ion Conductors in Solid Oxide Fuel Cells * The Influence of Anion Substitution on Some Phosphate-based Ion Conducting Glasses * Lithium Intercalation in Carbon Electrodes and its Relevance in Rocking Chair Batteries * Chemical Sensors using Proton Conducting Ceramics * NMR/NQR Studies of Y-Ba-Cu-O Superconductors * Silver Molybdate Glasses and Battery Systems * New Highly Conducting Polymer Ionics and their Application in Electrochemical Devices * Study of Li Electrokinetics on Oligomeric Electrolytes using Microelectrodes * Calculation of Conductivity for Mixed-Phase Electrolytes PEO-MX-Immiscible Additive by Means of Effective Medium Theory * II. CONTRIBUTED PAPERS * Phase Relationship and Electrical Conductivity of Sr-V-O System with Vanadium Suboxide * Amorphous Li+ Ionic Conductors in Li2SO4-Li2O-P2O5 System * Fast Ion Transport in KCl-Al2O3 Composites * The Effect of the Second Phase Precipitation on the Ionic Conductivity of Zr0.85Mg0.15O1.85 * Conductivity Measurements and Phase Relationships in CaCl2-CaHCl Solid Electrolyte * Relationships Between Crystal Structure and Sodium Ion Conductivity in Na7Fe4(AsO4)6 and Na3Al2(AsO4)3 * Electrical Conductivity and Solubility Limit of Ti4+ Ion in Na1+x TiyZr2-ySixP3-xO12 System * Study on Sodium Fast Ion Conductors of Na1+3xAlxTi2-xSi2xP3-2xO12 System * Influences of Zirconia on the Properties of β''-Alumina Ceramics * Decay of Luminescence from Cr3+ Ions in β-Alumina * Lithium Ion Conductivity in the Li4XO4-Li2

  20. Solid state technology: A compilation. [on semiconductor devices

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A compilation, covering selected solid state devices developed and integrated into systems by NASA to improve performance, is presented. Data are also given on device shielding in hostile radiation environments.

  1. Solid-State Synthesis of a Thermochromic Compound

    NASA Astrophysics Data System (ADS)

    Changyun, Chen; Zhihua, Zhou; Yiming, Zhou; Jiangyan, Du

    2000-09-01

    Bis(diethylammonium) tetrachloronickelate(II) was prepared by solid-state reaction at mild temperature. Classroom demonstration of the synthesis and discussions of thermochromic mechanism of the compound prepared were described.

  2. Electronic aperture control devised for solid state imaging system

    NASA Technical Reports Server (NTRS)

    Anders, R. A.; Callahan, D. E.; Mc Cann, D. H.

    1968-01-01

    Electronic means of performing the equivalent of automatic aperture control has been devised for the new class of television cameras that incorporates a solid state imaging device in the form of phototransistor mosaic sensors.

  3. Solid-state Bonding of Superplastic Aluminum Alloy 7475 Sheet

    NASA Technical Reports Server (NTRS)

    Byun, T. D. S.; Vastava, R. B.

    1985-01-01

    Experimental works were carried out to study the feasibility of solid state bonding of superplastic aluminum 7475 sheet. Amount of deformation, bonding time, surface cleaning method and intermediate layer were the process parameters investigated. Other parameters, held constant by the superplastic forming condition which is required to obtain a concurrent solid state bonding, are bonding temperature, bonding pressure and atmosphere. Bond integrity was evaluated through metallographic examination, X-ray line scan analysis, SEM fractographic analysis and lap shear tests. The early results of the development program indicated that sound solid state bonding was accomplished for this high strength 7475 alloy with significant amounts of deformation. A thin intermediate layer of the soft 5052 aluminum alloy aided in achieving a solid state bonding by reducing the required amount of plastic deformation at the interface. Bond strength was substantially increased by a post bond heat treatment.

  4. Solid State Photochemical Isomerization: A Convenient Laboratory Experiment.

    ERIC Educational Resources Information Center

    Burton, W. B.

    1979-01-01

    Describes the use of benzophenone in the role of a solid state sensitizer in a photochemical isomerization and as an indicator in preparative layer chromatography for purification of the isomeride. (Author/SA)

  5. Plasmon-Assisted Nd(3+)-Based Solid-State Nanolaser.

    PubMed

    Molina, Pablo; Yraola, Eduardo; Ramírez, Mariola O; Tserkezis, Christos; Plaza, José L; Aizpurua, Javier; Bravo-Abad, Jorge; Bausá, Luisa E

    2016-02-10

    Solid-state lasers constitute essential tools in a variety of scientific and technological areas, being available in many different designs. However, although nanolasing has been successfully achieved for dyes and semiconductor gain media associated with plasmonic structures, the operation of solid-state lasers beyond the diffraction limit has not been reported yet. Here, we demonstrate room temperature laser action with subwavelength confinement in a Nd(3+)-based solid-state laser by means of the localized surface plasmon resonances supported by chains of metallic nanoparticles. We show a 50% reduction of the pump power at threshold and a remarkable 15-fold improvement of the slope efficiency with respect to the bulk laser operation. The results can be extended to the large diversity of solid-state lasers with the subsequent impact on their applications. PMID:26751848

  6. Solid-state X-band Combiner Study

    NASA Technical Reports Server (NTRS)

    Pitzalis, O., Jr.; Russell, K. J.

    1979-01-01

    The feasibility of developing solid-state amplifiers at 4 and 10 GHz for application in spacecraft altimeters was studied. Bipolar-transistor, field-effect-transistor, and Impatt-diode amplifier designs based on 1980 solid-state technology are investigated. Several output power levels of the pulsed, low-duty-factor amplifiers are considered at each frequency. Proposed transistor and diode amplifier designs are illustrated in block diagrams. Projections of size, weight, and primary power requirements are given for each design.

  7. Progress in solid state dye laser development

    SciTech Connect

    Hermes, R.E.

    1990-01-01

    A triaxial flashlamp (15 cm) was used to optically pump laser rods prepared from an acrylate based copolymer (0.95 cm O.D. {times} 10.0 cm L.). The performance of 13 laser dyes incorporated into this polymeric solid host is reported. The best lasing performance was obtained with sulforhodamine-B, with a calculated slope efficiency of 0.52% and a maximum single pulse output energy of 580 mJ. A commercially available fluorescent polymeric material was also evaluated. 12 refs., 2 figs.

  8. Solid State Division progress report, September 30, 1981

    SciTech Connect

    Not Available

    1982-04-01

    Progress made during the 19 months from March 1, 1980, through September 30, 1981, is reported in the following areas: theoretical solid state physics (surfaces, electronic and magnetic properties, particle-solid interactions, and laser annealing); surface and near-surface properties of solids (plasma materials interactions, ion-solid interactions, pulsed laser annealing, and semiconductor physics and photovoltaic conversion); defects in solids (radiation effects, fracture, and defects and impurities in insulating crystals); transport properties of solids (fast-ion conductors, superconductivity, and physical properties of insulating materials); neutron scattering (small-angle scattering, lattice dynamics, and magnetic properties); crystal growth and characterization (nuclear waste forms, ferroelectric mateirals, high-temperature materials, and special materials); and isotope research materials. Publications and papers are listed. (WHK)

  9. Microstructural analysis of solid-state resistance welds

    SciTech Connect

    Kanne, W.R.Jr.

    1993-07-01

    No melting is present in solid-state welds and the microstructure is therefore very different from the solidification structures found in fusion welds. Improved properties of the weld result from the solid-state metallurgical structure. Solid-state resistance welding therefore has advantages compared to fusion welding processes. Different types of solid-state resistance welds have been developed for several unique applications ranging from small tube closure welds to vessel fabrication welds. Solid-state resistance upset welds have a hot worked microstructure, usually with recrystallization near the mating surfaces. Quality of the weld can be related to the metallographic appearance of the bond line at the mating surfaces. Impurities such as oxidation effect both the appearance of the bond line and weld quality. Microstructural examination of flow lines can provide a remarkably clear picture of the deformation pattern, or upsetting, that occurs during welding. Unusual effects such as multiple interfaces can be clearly seen from microstructural examination. Hardness traverses across metallographic sections are used to relate weld area strength to microstructural characteristics. Solid-state weld and heat-affected zone strengths have been compared to base metal and to fusion weld strengths using hardness data.

  10. Microstructural analysis of solid-state resistance welds

    SciTech Connect

    Kanne, W.R.Jr.

    1993-01-01

    No melting is present in solid-state welds and the microstructure is therefore very different from the solidification structures found in fusion welds. Improved properties of the weld result from the solid-state metallurgical structure. Solid-state resistance welding therefore has advantages compared to fusion welding processes. Different types of solid-state resistance welds have been developed for several unique applications ranging from small tube closure welds to vessel fabrication welds. Solid-state resistance upset welds have a hot worked microstructure, usually with recrystallization near the mating surfaces. Quality of the weld can be related to the metallographic appearance of the bond line at the mating surfaces. Impurities such as oxidation effect both the appearance of the bond line and weld quality. Microstructural examination of flow lines can provide a remarkably clear picture of the deformation pattern, or upsetting, that occurs during welding. Unusual effects such as multiple interfaces can be clearly seen from microstructural examination. Hardness traverses across metallographic sections are used to relate weld area strength to microstructural characteristics. Solid-state weld and heat-affected zone strengths have been compared to base metal and to fusion weld strengths using hardness data.