Sample records for mixed temperatures led

  1. Temperature-dependent ion beam mixing

    SciTech Connect (OSTI)

    Rehn, L.E.; Alexander, D.E.

    1993-08-01T23:59:59.000Z

    Recent work on enhanced interdiffusion rates during ion-beam mixing at elevated temperatures is reviewed. As discussed previously, expected increase in ion-beam mixing rates due to `radiation-enhanced diffusion` (RED), i.e. the free migration of isolated vacancy and interstitial defects, is well documented in single-crystal specimens in the range of 0.4 to 0.6 of absolute melting temperature. In contrast, the increase often observed at somewhat lower temperatures during ion-beam mixing of polycrystalline specimens is not well understood. However, sufficient evidence is available to show that this increase reflects intracascade enhancement of a thermally-activated process that also occurs without irradiation. Recent evidence is presented which suggests that this process is Diffusion-induced Grain-Boundary Migration (DIGM). An important complementary conclusion is that because ion-beam mixing in single-crystal specimens exhibits no significant temperature dependence below that of RED, models that invoke only irradiation-specific phenomena, e.g., cascade-overlap, thermal-spikes, or liquid-diffusion, and hence which predict no difference in mixing behavior between single- or poly-crystalline specimens, cannot account for the existing results.

  2. Consequences of Mixed Pixels on Temperature Emissivity Separation

    SciTech Connect (OSTI)

    Heasler, Patrick G.; Foley, Michael G.; Thompson, Sandra E.

    2007-02-01T23:59:59.000Z

    This report investigates the effect that a mixed pixel can have on temperature/emissivity seperation (i.e. temperature/emissivity estimation using long-wave infra-red data). Almost all temperature/emissivity estimation methods are based on a model that assumes both temperature and emissivity within the imaged pixel is homogeneous. A mixed pixel has heterogeneous temperature/emissivity and therefore does not satisfy the assumption. Needless to say, this heterogeneity causes biases in the estimates and this report quantifies the magnitude of the biases.

  3. Non-Sooting, Low Flame Temperature Mixing-Controlled DI Diesel...

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

    Sooting, Low Flame Temperature Mixing-Controlled DI Diesel Combustion Non-Sooting, Low Flame Temperature Mixing-Controlled DI Diesel Combustion 2003 DEER Conference Presentation:...

  4. LED Update

    SciTech Connect (OSTI)

    Johnson, Mark L.; Gordon, Kelly L.

    2006-09-01T23:59:59.000Z

    This article, which will appear in RESIDENTIAL LIGHTING MAGAZINE, interviews PNNL's Kelly Gordon and presents the interview in question and answer format. The topic is a light emitting diode (LED) lighting also known as solid state lighting. Solid state lighting will be a new category in an energy efficient lighting fixture design competition called Lighting for Tomorrow sponsored by the US Department of Energy Emerging Technologies Office, the American Institute for Lighting, and the Consortium for Energy Efficiency. LED technology has been around since the ’60s, but it has been used mostly for indicator lights on electronics equipment. The big breakthrough was the development in the 1990s of blue LEDs which can be combined with the red and green LEDs that already existed to make white light. LEDs produce 25 to 40 lumens of light per watt of energy used, almost as much as a CFL (50 lumens per watt) and much more efficient than incandescent sources, which are around 15 lumens per watt. They are much longer lived and practical in harsh environments unsuitable for incandescent lighting. They are ready for niche applications now, like under-counter lighting and may be practical for additional applications as technological challenges are worked out and the technology is advancing in leaps and bounds.

  5. LED lamp

    DOE Patents [OSTI]

    Galvez, Miguel; Grossman, Kenneth; Betts, David

    2013-11-12T23:59:59.000Z

    There is herein described a lamp for providing white light comprising a plurality of light sources positioned on a substrate. Each of said light sources comprises a blue light emitting diode (LED) and a dome that substantially covers said LED. A first portion of said blue light from said LEDs is transmitted through said domes and a second portion of said blue light is converted into a red light by a first phosphor contained in said domes. A cover is disposed over all of said light sources that transmits at least a portion of said red and blue light emitted by said light sources. The cover contains a second phosphor that emits a yellow light in response to said blue light. The red, blue and yellow light combining to form the white light and the white light having a color rendering index (CRI) of at least about 80.

  6. Driving Down HB-LED Costs: Implementation of Process Simulation Tools and Temperature Control Methods of High Yield MOCVD Growth

    SciTech Connect (OSTI)

    William Quinn

    2012-04-30T23:59:59.000Z

    The overall objective of this multi-faceted program is to develop epitaxial growth systems that meet a goal of 75% (4X) cost reduction in the epitaxy phase of HB-LED manufacture. A 75% reduction in yielded epitaxy cost is necessary in order to achieve the cost goals for widespread penetration of HB-LEDâ??s into back-lighting units (BLU) for LCD panels and ultimately for solid-state lighting (SSL). To do this, the program will address significant improvements in overall equipment Cost of Ownership, or CoO. CoO is a model that includes all costs associated with the epitaxy portion of production. These aspects include cost of yield, capital cost, operational costs, and maintenance costs. We divide the program into three phases where later phases will incorporate the gains of prior phases. Phase one activities are enabling technologies. In collaboration with Sandia National Laboratories we develop a Fluent-compatible chemistry predictive model and a set of mid-infrared and near-ultraviolet pyrometer monitoring tools. Where previously the modeling of the reactor dynamics were studied within FLUENT alone, here, FLUENT and Chemkin are integrated into a comprehensive model of fluid dynamics and the most advanced transport equations developed for Chemkin. Specifically, the Chemkin model offered the key reaction terms for gas-phase nucleation, a key consideration in the optimization of the MOCVD process. This new predictive model is used to design new MOCVD reactors with optimized growth conditions and the newly developed pyrometers are used monitor and control the MOCVD process temperature to within 0.5°C run-to-run and within each wafer. This portion of the grant is in collaboration with partners at Sandia National Laboratories. Phase two activities are continuous improvement projects which extend the current reactor platform along the lines of improved operational efficiency, improved systems control for throughput, and carrier modifications for increased yield. Programmatically, improvements made in Phase I are applied to developments of Phase II when applicable. Phase three is the culmination of the individual tasks from both phases one and two applied to proposed production platforms. We selectively combine previously demonstrated tasks and other options to develop a high-volume production-worthy MOCVD system demonstrating >3x throughput, 1.3x capital efficiency, and 0.7x cost of ownership. In a parallel demonstration we validate the concept of an improved, larger deposition system which utilizes the predictive modeling of chemistry-based flow analysis and extensions of the improvements demonstrated on the current platforms. This validation includes the build and testing of a prototype version of the hardware and demonstration of 69% reduction in the cost of ownership. Also, in this phase we present a stand-alone project to develop a high-temperature system which improves source efficiency by 30% while concurrently increasing growth rate by 1.3x. The material quality is held to the same material quality specifications of our existing baseline processes. The merits of other line item tasks in phase three are discussed for inclusion on next-generation platforms.

  7. Temperature-Dependent Heterogeneous Efflorescence of Mixed Ammonium Sulfate/Calcium Carbonate Particles

    E-Print Network [OSTI]

    Temperature-Dependent Heterogeneous Efflorescence of Mixed Ammonium Sulfate/Calcium Carbonate sulfate/calcium carbonate microparticles. Deliquescence and efflorescence relative humidities and calcium carbonate and (b) supersaturated with respect to ammonium sulfate and saturated with respect

  8. Temperature dependence of ion-beam mixing in crystalline and amorphous germanium isotope multilayer structures

    SciTech Connect (OSTI)

    Radek, M.; Bracht, H., E-mail: bracht@uni-muenster.de [Institute of Materials Physics, Westfälische Wilhelms-Universität Münster, 48149 Münster (Germany); Posselt, M.; Liedke, B.; Schmidt, B. [Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, D-01328 Dresden (Germany); Bougeard, D. [Institut für Experimentelle und Angewandte Physik, 93040 Regensburg (Germany)

    2014-01-14T23:59:59.000Z

    Self-atom mixing induced by 310 keV gallium (Ga) ion implantation in crystalline and preamorphized germanium (Ge) at temperatures between 164 K and 623 K and a dose of 1?×?10{sup 15}?cm{sup ?2} is investigated using isotopic multilayer structures of alternating {sup 70}Ge and {sup nat}Ge layers grown by molecular beam epitaxy. The distribution of the implanted Ga atoms and the ion-beam induced depth-dependent self-atom mixing was determined by means of secondary ion mass spectrometry. Three different temperature regimes of self-atom mixing, i.e., low-, intermediate-, and high-temperature regimes are observed. At temperatures up to 423 K, the mixing is independent of the initial structure, whereas at 523?K, the intermixing of the preamorphized Ge structure is about twice as high as that of crystalline Ge. At 623?K, the intermixing of the initially amorphous Ge structure is strongly reduced and approaches the mixing of the crystalline material. The temperature dependence of ion-beam mixing is described by competitive amorphization and recrystallization processes.

  9. NON-SOOTING, LOW FLAME TEMPERATURE MIXING-CONTROLLED DI DIESEL COMBUSTION

    SciTech Connect (OSTI)

    Pickett, L; Siebers, D

    2003-08-24T23:59:59.000Z

    Methods of producing non-sooting, low flame temperature diesel combustion were investigated in an optically-accessible, quiescent constant-volume combustion vessel under mixing-controlled diesel combustion conditions. Combustion and soot processes of single, isolated fuel jets were studied after auto-ignition and transient premixed combustion and while the injector was fully-open (i.e. during the mixing-controlled phase of heat release for diesel combustion). The investigation showed that small injector tip orifices could be used to produce non-sooting and low flame temperature combustion simultaneously. The use of small orifices was shown to enable non-sooting and low flame temperature combustion in two different ways as summarized below. A more detailed description of the experimental methods and results is provided in Ref. [1-3]. First, using an injector tip with a 50 micron orifice and ambient oxygen concentrations as low as 10% (simulating the use of extensive EGR), a fuel jet was non-sooting at typical diesel ambient temperatures (1000 K). Second, using the same injector tip at a reduced ambient gas temperature (850 K), but with 21% oxygen, it was shown that non-sooting, mixing-controlled combustion occurred at the lift-off length in a fuel-air mixture with a cross-sectional average equivalence ratio of approximately 0.6-suggesting that the quasi-steady combustion was fuel-lean and thereby avoided the formation of a diffusion flame. The adiabatic flame temperature with reduced ambient oxygen concentration or fuel-lean combustion was approximately 2000 K, compared to typical diesel flame temperatures that exceed 2600 K. The 50 micron orifice results above were obtained using a No.2 diesel fuel. However, using an oxygenated fuel (20 wt% oxygen), the investigation showed that the same low temperature combustion, either with reduced ambient oxygen concentration or fuel-lean combustion, was realized with a 100 micron orifice. Although these single, isolated jets do not have jet-jet interactions that would occur in realistic engines, the results are useful for understanding limiting-case behavior of single-jet mixing and combustion during an injection event. The non-sooting and low flame temperature mixing-controlled combustion realized using small orifice tips suggests that the use of small orifices offers the potential for a simultaneous soot and NOx reduction in an engine, much like diesel HCCI combustion. However, further research is needed to determine whether these methods could be successfully implemented in real engines.

  10. Method for stabilizing low-level mixed wastes at room temperature

    DOE Patents [OSTI]

    Wagh, A.S.; Singh, D.

    1997-07-08T23:59:59.000Z

    A method to stabilize solid and liquid waste at room temperature is provided comprising combining solid waste with a starter oxide to obtain a powder, contacting the powder with an acid solution to create a slurry, said acid solution containing the liquid waste, shaping the now-mixed slurry into a predetermined form, and allowing the now-formed slurry to set. The invention also provides for a method to encapsulate and stabilize waste containing cesium comprising combining the waste with Zr(OH){sub 4} to create a solid-phase mixture, mixing phosphoric acid with the solid-phase mixture to create a slurry, subjecting the slurry to pressure; and allowing the now pressurized slurry to set. Lastly, the invention provides for a method to stabilize liquid waste, comprising supplying a powder containing magnesium, sodium and phosphate in predetermined proportions, mixing said powder with the liquid waste, such as tritium, and allowing the resulting slurry to set. 4 figs.

  11. Method for stabilizing low-level mixed wastes at room temperature

    DOE Patents [OSTI]

    Wagh, Arun S. (Joliet, IL); Singh, Dileep (Westmont, IL)

    1997-01-01T23:59:59.000Z

    A method to stabilize solid and liquid waste at room temperature is provided comprising combining solid waste with a starter oxide to obtain a powder, contacting the powder with an acid solution to create a slurry, said acid solution containing the liquid waste, shaping the now-mixed slurry into a predetermined form, and allowing the now-formed slurry to set. The invention also provides for a method to encapsulate and stabilize waste containing cesium comprising combining the waste with Zr(OH).sub.4 to create a solid-phase mixture, mixing phosphoric acid with the solid-phase mixture to create a slurry, subjecting the slurry to pressure; and allowing the now pressurized slurry to set. Lastly, the invention provides for a method to stabilize liquid waste, comprising supplying a powder containing magnesium, sodium and phosphate in predetermined proportions, mixing said powder with the liquid waste, such as tritium, and allowing the resulting slurry to set.

  12. LED Market Intelligence Report

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

    early adopters of LED technologies, particularly around dimming capabilities. 16 LED Market Intelligence Report Home Depot Walmart Cree Philips TCP GE LSG Osram Feit Costco...

  13. OSMOTIC COEFFICIENTS, SOLUBILITIES, AND DELIQUESCENCE RELATIONS IN MIXED AQUEOUS SALT SOLUTIONS AT ELEVATED TEMPERATURE

    SciTech Connect (OSTI)

    M.S. Gruszkiewicz; D.A. Palmer

    2006-02-22T23:59:59.000Z

    While thermodynamic properties of pure aqueous electrolytes are relatively well known at ambient temperature, there are far fewer data for binary systems extending to elevated temperatures and high concentrations. There is no general theoretically sound basis for prediction of the temperature dependence of ionic activities, and consequently temperature extrapolations based on ambient temperature data and empirical equations are uncertain and require empirical verification. Thermodynamic properties of mixed brines in a wide range of concentrations would enhance the understanding and precise modeling of the effects of deliquescence of initially dry solids in humid air in geological environments and in modeling the composition of waters during heating, cooling, evaporation or condensation processes. These conditions are of interest in the analysis of waters on metal surfaces at the proposed radioactive waste repository at Yucca Mountain, Nevada. The results obtained in this project will be useful for modeling the long-term evolution of the chemical environment, and this in turn is useful for the analysis of the corrosion of waste packages. In particular, there are few reliable experimental data available on the relationship between relative humidity and composition that reveals the eutonic points of the mixtures and the mixture deliquescence RH. The deliquescence RH for multicomponent mixtures is lower than that of pure component or binary solutions, but is not easy to predict quantitatively since the solutions are highly nonideal. In this work we used the ORNL low-temperature and high-temperature isopiestic facilities, capable of precise measurements of vapor pressure between ambient temperature and 250 C for determination of not only osmotic coefficients, but also solubilities and deliquescence points of aqueous mixed solutions in a range of temperatures. In addition to standard solutions of CaCl{sub 2}, LiCl, and NaCl used as references, precise direct-pressure measurements were also made at elevated temperatures. The project included multicomponent mixtures useful for verification of models, and a set of binary solutions with common ions (such as KNO{sub 3} + NaNO{sub 3}, KNO{sub 3} + Ca(NO{sub 3}){sub 2}, NaNO{sub 3} + Na{sub 2}SO{sub 4}, and KNO{sub 3} + K{sub 2}SO{sub 4}) needed for determination of the mixing parameters in the Pitzer ion-interaction model for mixtures. The results are compared with existing experimental results and model predictions.

  14. Solving the 'Green Gap' in LED Technology

    Broader source: Energy.gov [DOE]

    One long-standing high-priority research area for DOE is to increase the efficiency of deep green LEDs. Although most products today use phosphor conversion (PC) to produce white light from a blue LED, having a good green source could lead to color-mixed white sources that would avoid the losses associated with the PC approach.

  15. LEDs_3LEDs_3 current efficiency

    E-Print Network [OSTI]

    Pulfrey, David L.

    efficiencySec. 8.2 From our toolbox Current efficiency #12;4 Light extraction efficiencyLight extraction extraction efficiencyDesign to improve extraction efficiencySec. 8.4 What are the features of this LED from;6 Various efficienciesVarious efficienciesSecs. 8.4, 8.5 Present record is 56%Wall-plug efficiency Wall

  16. LED Lighting Retrofit

    E-Print Network [OSTI]

    Shaw-Meadow, N.

    2011-01-01T23:59:59.000Z

    ? Municipal Street Lighting Consortium ? American Public Power Association (APPA) ? Demonstration in Energy Efficiency Development (DEED) ? Source of funding and database of completed LED roadway projects 6 Rules of the Road ESL-KT-11-11-57 CATEE 2011..., 2011 ? 9 Solar-Assisted LED Case Study LaQuinta Hotel, Cedar Park, Texas ? Utilizes 18 - ActiveLED Solar-Assisted Parking Lot Lights ? Utilizes ?power management? to extend battery life while handling light output ? Reduces load which reduces PV...

  17. LED Lighting Basics

    Broader source: Energy.gov [DOE]

    Light-Emitting diodes (LEDs) efficiently produce light in a fundamentally different way than any legacy or traditional source of light.

  18. Sandia National Laboratories: LED

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

    electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

  19. LED MR16 Lamps

    Broader source: Energy.gov [DOE]

    The following CALiPER report provides detailed analysis of LED MR16 lamp performance, covering basic performance characteristics as well as subjective evaluation of beam, shadow, and color quality. Pending reports will offer analysis on performance attributes that are not captured by LM-79 testing. These reports are intended to educate the industry on market trends, potential issues, and important areas for improvement.

  20. Global LED Manufacturing

    Energy Savers [EERE]

    0.20.5W 5630 PPA 0.51.0W 7030 PCT XVGA HDMI UHD 4K2K UHD 8K4K 0.81.2W 3030 EMC 1.22.0W 3535 EMC w Flip-Chip 0.50.8W 2835 PCT ? 1.01.5 W ???? Revolution of LED...

  1. LED Price Tracking Form

    Broader source: Energy.gov [DOE]

    DOE intends to update the SSL Pricing and Efficacy Trend Analysis for Utility Program Planning report on an annual basis, but doing so requires that we have sufficient product and purchase data including acquisition date, purchase price, product category, and rated initial lumens. Those interested in helping collect this data are asked to use the LED Price Tracking FormMicrosoft Excel and follow the instructions for submitting data.

  2. LED PAR38 Lamps

    Broader source: Energy.gov [DOE]

    The following CALiPER reports provide detailed analysis of LED PAR38 lamp performance, covering basic performance characteristics as well as subjective evaluation of beam, shadow, and color quality. Pending reports will offer analysis on flicker, dimming and power quality characteristics; stress testing; and lumen and chromaticity maintenance. These reports are intended to educate the industry on market trends, potential issues, and important areas for improvement.

  3. The Explorationon the Energy Saving Potential of an Innovative Dual-temperature Air Conditioner and the Mechanism of the Theoretical Mixed Refrigeration Cycl

    E-Print Network [OSTI]

    Zhao,L.; Zhao,X.; Hu,A.

    2014-01-01T23:59:59.000Z

    The Exploration on the Energy Saving Potential of an Innovative Dual-temperature Air Conditioner and the Mechanism of the Theoretical Mixed Refrigeration Cycle Zhao Lei, Zhao Xijin, Hu Andu Professor, graduate student, graduate student...-temperature air conditioning system and its corresponding theoretical mixed refrigeration cycle are proposed. This consists of a separate air handling unit and a metal radiation panel as the dual-temperature evaporators, a compressor, a condenser, two thermal...

  4. New GATEWAY Report Monitors LED System Performance in a High...

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

    the light. The Yuma site is an extreme environment: high ambient temperatures and direct solar radiation heat up the luminaires throughout the day, and at sunset the LED...

  5. Semiconductors 4-bit I2C LED dimmer

    E-Print Network [OSTI]

    Berns, Hans-Gerd

    with SMBus · Internal power-on reset · Noise filter on SCL/SDA inputs · 4 open drain outputs directly drive for dimming LEDs in 256 discrete steps for Red/Green/Blue (RGB) color mixing and back light applications to 1.69 second. The open drain outputs directly drive the LEDs with maximum output sink current of 25 m

  6. White LED with High Package Extraction Efficiency

    SciTech Connect (OSTI)

    Yi Zheng; Matthew Stough

    2008-09-30T23:59:59.000Z

    The goal of this project is to develop a high efficiency phosphor converting (white) Light Emitting Diode (pcLED) 1-Watt package through an increase in package extraction efficiency. A transparent/translucent monolithic phosphor is proposed to replace the powdered phosphor to reduce the scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is proposed between blue LED die and phosphor layer to recover inward yellow emission. At the end of the project we expect to recycle approximately 50% of the unrecovered backward light in current package construction, and develop a pcLED device with 80 lm/W{sub e} using our technology improvements and commercially available chip/package source. The success of the project will benefit luminous efficacy of white LEDs by increasing package extraction efficiency. In most phosphor-converting white LEDs, the white color is obtained by combining a blue LED die (or chip) with a powdered phosphor layer. The phosphor partially absorbs the blue light from the LED die and converts it into a broad green-yellow emission. The mixture of the transmitted blue light and green-yellow light emerging gives white light. There are two major drawbacks for current pcLEDs in terms of package extraction efficiency. The first is light scattering caused by phosphor particles. When the blue photons from the chip strike the phosphor particles, some blue light will be scattered by phosphor particles. Converted yellow emission photons are also scattered. A portion of scattered light is in the backward direction toward the die. The amount of this backward light varies and depends in part on the particle size of phosphors. The other drawback is that yellow emission from phosphor powders is isotropic. Although some backward light can be recovered by the reflector in current LED packages, there is still a portion of backward light that will be absorbed inside the package and further converted to heat. Heat generated in the package may cause a deterioration of encapsulant materials, affecting the performance of both the LED die and phosphor, leading to a decrease in the luminous efficacy over lifetime. Recent studies from research groups at Rensselaer Polytechnic Institute found that, under the condition to obtain a white light, about 40% of the light is transmitted outward of the phosphor layer and 60% of the light is reflected inward.1,2 It is claimed that using scattered photon extraction (SPE) technique, luminous efficacy is increased by 60%. In this project, a transparent/translucent monolithic phosphor was used to replace the powdered phosphor layer. In the normal pcLED package, the powdered phosphor is mixed with silicone either to be deposited on the top of LED die forming a chip level conversion (CLC) white LED or to be casted in the package forming a volume conversion white LED. In the monolithic phosphors there are no phosphor powder/silicone interfaces so it can reduce the light scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is inserted in the white LED package between the blue LED die and phosphor layer. It will selectively transmit the blue light from the LED die and reflect the phosphor's yellow inward emission outward. The two technologies try to recover backward light to the outward direction in the pcLED package thereby improving the package extraction efficiency.

  7. LED Record Efficacy and Brightness

    Broader source: Energy.gov [DOE]

    Designed for general lighting applications such as street, industrial, and parking garage lighting, the Cree XLamp® power LED sets new records for LED brightness and efficacy, up to 85 lm/W at 350 mA. The XLamp utilizes Cree's performance breakthrough EZBright™ LED chip; both products include technology that was developed in part with R&D funding support from DOE.

  8. The Application of Fluorescence Lifetime Imaging Microscopy to Quantitatively Map Mixing and Temperature in Microfluidic Systems 

    E-Print Network [OSTI]

    Graham, Emmelyn M

    2008-01-01T23:59:59.000Z

    The technique of Fluorescence Lifetime Imaging Microscopy (FLIM) has been employed to quantitatively and spatially map the fluid composition and temperature within microfluidic systems. A molecular probe with a ...

  9. The production of temperature and salinity variance and covariance : implications for mixing

    E-Print Network [OSTI]

    Schanze, Julian J. (Julian Johannes)

    2013-01-01T23:59:59.000Z

    Large-scale thermal forcing and freshwater fluxes play an essential role in setting temperature and salinity in the ocean. A number of recent estimates of the global oceanic freshwater balance as well as the global oceanic ...

  10. Measuring LCSTs by Novel Temperature Gradient Methods: Evidence for Intermolecular Interactions in Mixed Polymer Solutions

    E-Print Network [OSTI]

    the precipitation mechanisms are often complex, it is generally accepted that the desorption of water molecules from the temperature along the tube was a simple matter of measuring the lengthwise position. As a demonstration inverted microscope by employing dark field microscopy (Figure 2). Interestingl

  11. Synthesis and crystallographic study of Pb-Sr hydroxyapatite solid solutions by high temperature mixing method under hydrothermal conditions

    SciTech Connect (OSTI)

    Zhu Kongjun, E-mail: kjzhu@nuaa.edu.cn [Aeronautical Key Laboratory for Smart Materials and Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Yanagisawa, Kazumichi [Research Laboratory of Hydrothermal Chemistry, Faculty of Science, Kochi University, Kochi-shi 780-8520 (Japan); Shimanouchi, Rie [Department of Material Science, Faculty of Science, Kochi University, Kochi-shi, 780-8520 (Japan); Onda, Ayumu; Kajiyoshi, Koji [Research Laboratory of Hydrothermal Chemistry, Faculty of Science, Kochi University, Kochi-shi 780-8520 (Japan); Qiu Jinhao [Aeronautical Key Laboratory for Smart Materials and Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

    2009-06-03T23:59:59.000Z

    The solid solutions in the system of Pb and Sr hydroxyapatite, Sr{sub 10-x}Pb{sub x}HAp (x = 0-10), were successfully synthesized by high-temperature mixing method (HTMM) at 160 deg. C for 12 h under hydrothermal conditions. The samples were characterized by X-ray diffraction, chemical analysis and electron microscopic observation, and the site of the metal ions in the solid solutions was analyzed with the Rietveld method. The lattice constants, both a and c, of the solid solutions varied linearly with Pb content. It was found that Pb ions in the solid solutions preferentially occupied the M(2) site in the apatite structure. HTMM gives Sr-Pb HAp solid solutions much better crystallization. However, due to the formation of intermediate compound of Pb{sub 3}O{sub 2}(OH){sub 2} in the Pb(NO{sub 3}){sub 2}.4H{sub 2}O solution before mixing with (NH{sub 4}){sub 2}HPO{sub 4} solution at 160 deg. C, HTMM causes the decrease of crystallization of the samples with high Pb content.

  12. The oxidation of Type 310S stainless steel in mixed gases at elevated temperatures

    SciTech Connect (OSTI)

    Wolf, J.S. [Clemson Univ., SC (United States). Dept. of Mechanical Engineering; Cavin, O.B.; DeVan, J.H. [Oak Ridge National Lab., TN (United States)

    1992-04-01T23:59:59.000Z

    Sheet specimens of Type 310S stainless steel were exposed to air as well as to ``lean`` and ``rich`` sulfidizing atmospheres at temperatures near 900{degrees}C to determine the relationships that exist between the scale structure, the rate of reaction, and the stresses generated during exposure. One goal of this experimental research program was to examine how these factors might be related to the breakdown of protective scales in sulfidizing atmospheres. It was found that the scales formed in air and the ``lean`` atmosphere are protective and non-spalling while those formed in the ``rich`` atmosphere spall, initially react at rates 1000 times greater than counterparts in less aggressive atmospheres, and later exhibit a ``breakaway``-type rapid reaction. Only those scales formed in air provide the cooperative, tractive interfacial forces required to produce uniform dilatation and deformation of the substrate. However, evidence exists for at least localized stresses in all of the scales examined.

  13. The oxidation of Type 310S stainless steel in mixed gases at elevated temperatures

    SciTech Connect (OSTI)

    Wolf, J.S. (Clemson Univ., SC (United States). Dept. of Mechanical Engineering); Cavin, O.B.; DeVan, J.H. (Oak Ridge National Lab., TN (United States))

    1992-04-01T23:59:59.000Z

    Sheet specimens of Type 310S stainless steel were exposed to air as well as to lean'' and rich'' sulfidizing atmospheres at temperatures near 900{degrees}C to determine the relationships that exist between the scale structure, the rate of reaction, and the stresses generated during exposure. One goal of this experimental research program was to examine how these factors might be related to the breakdown of protective scales in sulfidizing atmospheres. It was found that the scales formed in air and the lean'' atmosphere are protective and non-spalling while those formed in the rich'' atmosphere spall, initially react at rates 1000 times greater than counterparts in less aggressive atmospheres, and later exhibit a breakaway''-type rapid reaction. Only those scales formed in air provide the cooperative, tractive interfacial forces required to produce uniform dilatation and deformation of the substrate. However, evidence exists for at least localized stresses in all of the scales examined.

  14. Ongoing LED RD Challenges (LED droop still challenge)

    Energy Savers [EERE]

    and Nonpolar GaN Semi polar GaN SOLUTION New GaN Crystal Planes * Semipolar planes for blue, green and yellow LEDs A. Romanov et al. : J. Appl. Phys. 100 (2006) 023533. (1122)...

  15. Metacapacitors for LED Lighting: Metacapacitors

    SciTech Connect (OSTI)

    None

    2010-09-02T23:59:59.000Z

    ADEPT Project: The CUNY Energy Institute is developing less expensive, more efficient, smaller, and longer-lasting power converters for energy-efficient LED lights. LEDs produce light more efficiently than incandescent lights and last significantly longer than compact fluorescent bulbs, but they require more sophisticated power converter technology, which increases their cost. LEDs need more sophisticated converters because they require a different type of power (low voltage direct current, or DC) than what's generally supplied by power outlets. The CUNY Energy Institute is developing sophisticated power converters for LEDs that contain capacitors made from new, nanoscale materials. Capacitors are electrical components that are used to store energy. CUNY's unique capacitors are configured with advanced power circuits to more efficiently control and convert power to the LED lighting source. They also eliminate the need for large magnetic components, instead relying on networks of capacitors that can be easily printed on plastic substrate. CUNY's prototype LED power converter already meets DOE's 2020 projections for the energy efficiency of LED power converters.

  16. Integrated LED-based luminare for general lighting

    DOE Patents [OSTI]

    Dowling, Kevin J.; Lys, Ihor A.; Roberge, Brian; Williamson, Ryan C.; Roberts, Ron; Datta, Michael; Mollnow, Tomas; Morgan, Frederick M.

    2013-03-05T23:59:59.000Z

    Lighting apparatus and methods employing LED light sources are described. The LED light sources are integrated with other components in the form of a luminaire or other general purpose lighting structure. Some of the lighting structures are formed as Parabolic Aluminum Reflector (PAR) luminaires, allowing them to be inserted into conventional sockets. The lighting structures display beneficial operating characteristics, such as efficient operation, high thermal dissipation, high output, and good color mixing.

  17. Finite temperature corrections and embedded strings in noncommutative geometry and the standard model with neutrino mixing

    SciTech Connect (OSTI)

    Martins, R. A. [Centro de Analise Matematica, Geometria e Sistemas Dinamicos, Departamento de Matematica, Instituto Superior Tecnico, Avenida Rovisco Pais, 1049-001 Lisbon (Portugal)

    2007-08-15T23:59:59.000Z

    The recent extension of the standard model to include massive neutrinos in the framework of noncommutative geometry and the spectral action principle involves new scalar fields and their interactions with the usual complex scalar doublet. After ensuring that they bring no unphysical consequences, we address the question of how these fields affect the physics predicted in the Weinberg-Salam theory, particularly in the context of the electroweak phase transition. Applying the Dolan-Jackiw procedure, we calculate the finite temperature corrections, and find that the phase transition is first order. The new scalar interactions significantly improve the stability of the electroweak Z string, through the 'bag' phenomenon described by Vachaspati and Watkins ['Bound states can stabilize electroweak strings', Phys. Lett. B 318, 163-168 (1993)]. (Recently, cosmic strings have climbed back into interest due to a new evidence.) Sourced by static embedded strings, an internal space analogy of Cartan's torsion is drawn, and a possible Higgs-force-like 'gravitational' effect of this nonpropagating torsion on the fermion masses is described. We also check that the field generating the Majorana mass for the {nu}{sub R} is nonzero in the physical vacuum.

  18. Sandia National Laboratories: white LED

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

    electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

  19. Sandia National Laboratories: Red LED

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

    electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

  20. Sandia National Laboratories: Blue LED

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

    electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

  1. Maintenance Practices for LED Streetlights

    Broader source: Energy.gov [DOE]

    This April 14, 2014 webinar answered important questions about the maintenance and reliability of LED streetlights, and how to take these issues into account when planning and preparing for a...

  2. Mixing and flame structures inferred from OH-PLIF for conventional and low-temperature diesel engine combustion

    SciTech Connect (OSTI)

    Singh, Satbir [General Motors Research and Development, Warren, MI 48090 (United States); Musculus, Mark P.B. [Sandia National Laboratories, Livermore, CA 94551 (United States); Reitz, Rolf D. [Department of Mechanical Engineering, University of Wisconsin, Madison, WI 53706 (United States)

    2009-10-15T23:59:59.000Z

    The structure of first- and second-stage combustion is investigated in a heavy-duty, single-cylinder optical engine using chemiluminescence imaging, Mie-scatter imaging of liquid-fuel, and OH planar laser-induced fluorescence (OH-PLIF) along with calculations of fluorescence quenching. Three different diesel combustion modes are studied: conventional non-diluted high-temperature combustion (HTC) with either (1) short or (2) long ignition delay, and (3) highly diluted low-temperature combustion (LTC) with early fuel injection. For the short ignition delay HTC condition, the OH fluorescence images show that second-stage combustion occurs mainly on the fuel jet periphery in a thickness of about 1 mm. For the long ignition delay HTC condition, the second-stage combustion zone on the jet periphery is thicker (5-6 mm). For the early-injection LTC condition, the second-stage combustion is even thicker (20-25 mm) and occurs only in the down-stream regions of the jet. The relationship between OH concentration and OH-PLIF intensity over a range of equivalence ratios is estimated from quenching calculations using collider species concentrations predicted by chemical kinetics simulations of combustion. The calculations show that both OH concentration and OH-PLIF intensity peak near stoichiometric mixtures and fall by an order of magnitude or more for equivalence ratios less than 0.2-0.4 and greater than 1.4-1.6. Using the OH fluorescence quenching predictions together with OH-PLIF images, quantitative boundaries for mixing are established for the three engine combustion modes. (author)

  3. Optimized Phosphors for Warm White LED Light Engines

    SciTech Connect (OSTI)

    Setlur, Anant; Brewster, Megan; Garcia, Florencio; Hill, M. Christine; Lyons, Robert; Murphy, James; Stecher, Tom; Stoklosa, Stan; Weaver, Stan; Happek, Uwe; Aesram, Danny; Deshpande, Anirudha

    2012-07-30T23:59:59.000Z

    The objective of this program is to develop phosphor systems and LED light engines that have steady-state LED efficacies (using LEDs with a 60% wall-plug efficiency) of 105–120 lm/W with correlated color temperatures (CCT) ~3000 K, color rendering indices (CRI) >85, <0.003 distance from the blackbody curve (dbb), and <2% loss in phosphor efficiency under high temperature, high humidity conditions. In order to reach these goals, this involves the composition and processing optimization of phosphors previously developed by GE in combination with light engine package modification.

  4. LED Lighting Facts®

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED Lighting Facts LEDLED

  5. LED lamp power management system and method

    DOE Patents [OSTI]

    Gaines, James; Clauberg, Bernd; Van Erp, Josephus A. M.

    2013-03-19T23:59:59.000Z

    An LED lamp power management system and method including an LED lamp having an LED controller 58; a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 reduces power loss in one of the channel switch 62 and the shunt switch 68 when LED lamp electronics power loss (P.sub.loss) exceeds an LED lamp electronics power loss limit (P.sub.lim); and each of the channel switches 62 receives a channel switch control signal 63 from the LED controller 58 and each of the shunt switches 68 receives a shunt switch control signal 69 from the LED controller 58.

  6. LED lamp color control system and method

    DOE Patents [OSTI]

    Gaines, James; Clauberg, Bernd; Van Erp, Josephus A.M.

    2013-02-05T23:59:59.000Z

    An LED lamp color control system and method including an LED lamp having an LED controller 58; and a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 determines whether the LED source 80 is in a feedback controllable range, stores measured optical flux for the LED source 80 when the LED source 80 is in the feedback controllable range, and bypasses storing the measured optical flux when the LED source 80 is not in the feedback controllable range.

  7. Multicolor, High Efficiency, Nanotextured LEDs

    SciTech Connect (OSTI)

    Jung Han; Arto Nurmikko

    2011-09-30T23:59:59.000Z

    We report on research results in this project which synergize advanced material science approaches with fundamental optical physics concepts pertaining to light-matter interaction, with the goal of solving seminal problems for the development of very high performance light emitting diodes (LEDs) in the blue and green for Solid State Lighting applications. Accomplishments in the duration of the contract period include (i) heteroepitaxy of nitrogen-polar LEDs on sapphire, (ii) heteroepitaxy of semipolar (11{bar 2}2) green LEDs on sapphire, (iii) synthesis of quantum-dot loaded nanoporous GaN that emits white light without phosphor conversion, (iv) demonstration of the highest quality semipolar (11{bar 2}2) GaN on sapphire using orientation-controlled epitaxy, (v) synthesis of nanoscale GaN and InGaN medium, and (vi) development of a novel liftoff process for manufacturing GaN thin-film vertical LEDs. The body of results is presented in this report shows how a solid foundation has been laid, with several noticeable accomplishments, for innovative research, consistent with the stated milestones.

  8. Low Emission Development Strategies (LEDS): Technical, Institutional...

    Open Energy Info (EERE)

    Strategies (LEDS): Technical, Institutional and Policy Lessons Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Low Emission Development Strategies (LEDS): Technical,...

  9. LED Chips and Packaging for 120 LPW SSL Component

    SciTech Connect (OSTI)

    James Ibbetson

    2009-09-30T23:59:59.000Z

    Cree has developed a new, high-efficiency, low-cost, light emitting diode (LED) lamp module that should be capable of replacing standard, halogen, fluorescent and metal halide lamps based on the total cost of ownership. White LEDs are produced by combining one or more saturated color LEDs with a phosphor or other light down-converting media to achieve white broad-band illumination. This two year project addressed LED chip and package efficiency improvements to establish a technology platform suitable for low-cost, high-efficiency commercial luminaires. Novel photonic-crystal LEDs were developed to improve the light extraction efficiency of blue GaN-based LEDs compared to the baseline technology. Improved packaging designs that reduced down-conversion and absorption related light losses, led to a higher overall LED efficiency. Specifically, blue LEDs were demonstrated with light output nearing 600 mW and an external quantum efficiency greater than 60 percent (using 1 mm2 chips at an operating current of 350 mA). The results were achieved using a novel, production capable photonic-crystal LED fabrication process. These LEDs formed the basis for a multi-chip white lamp module prototype, which provided 510 lumens light output at a correlated color temperature (CCT) of 3875 K and an operating current of 350 mA per 1mm2 chip. The overall conversion efficiency at 4100 K improved to ~ 65%. The resulting efficacy is 112 lumens per watt (LPW) â?? a 33% improvement over the start of the project. In addition, a proof-of-concept luminaire was demonstrated that provided a flux of 1700 lumens at a 3842 K CCT.

  10. WhiteOptics' Low-Cost Reflector Composite Boosts LED Fixture Efficiency

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, WhiteOptics has developed a composite coating that can be used to improve efficiency in backlit, indirect, and cavity-mixing LED luminaire designs by maximizing light reflection and output. The highly diffuse coating, which is based on a novel high-reflectance particle technology, allows for uniform distribution of light without exaggerating the point-source nature of the LEDs, and is intended to offer an overall system cost-improving solution for LED optics.

  11. Mixing it up - Measuring diffusion in supercooled liquid solutions of methanol and ethanol at temperatures near the glass transition

    SciTech Connect (OSTI)

    Matthiesen, Jesper; Smith, R. Scott; Kay, Bruce D.

    2011-03-17T23:59:59.000Z

    Do liquid mixtures, cooled to temperatures below their freezing point, behave as normal liquids? We address this question using nanoscale films of methanol and ethanol supercooled liquid solutions of varying composition (7 -93% methanol) at temperatures near their glass transition,Tg. The permeation of Kr through these films is used to determine the diffusivities of the supercooled liquid mixtures. We find that the temperature dependent diffusivities of the mixtures are well-fit by a Vogel-Fulcher-Tamman equation indicating that the mixtures exhibit fragile behavior at temperatures just above their Tg. Further, for a given temperature, the composition dependent diffusivity is well-fit by a Vignes-type equation, i.e. the diffusivity of any mixture can be predicted using an exponential weighting of the diffusion of the pure methanol and ethanol diffusivities. These results show that deeply supercooled liquid mixtures can be used to provide valuable insight into the properties of normal liquid mixtures.

  12. LOW-COST LED LUMINAIRE FOR GENERAL ILLUMINATION

    SciTech Connect (OSTI)

    Lowes, Ted

    2014-07-31T23:59:59.000Z

    During this two-year Solid-State Lighting (SSL) Manufacturing R&D project Cree developed novel light emitting diode (LED) technologies contributing to a cost-optimized, efficient LED troffer luminaire platform emitting at ~3500K correlated color temperature (CCT) at a color rendering index (CRI) of >90. To successfully achieve program goals, Cree used a comprehensive approach to address cost reduction of the various optical, thermal and electrical subsystems in the luminaire without impacting performance. These developments built on Cree’s high- brightness, low-cost LED platforms to design a novel LED component architecture that will enable low-cost troffer luminaire designs with high total system efficacy. The project scope included cost reductions to nearly all major troffer subsystems as well as assembly costs. For example, no thermal management components were included in the troffer, owing to the optimized distribution of compact low- to mid-power LEDs. It is estimated that a significant manufacturing cost savings will result relative to Cree’s conventional troffers at the start of the project. A chief project accomplishment was the successful development of a new compact, high-efficacy LED component geometry with a broad far-field intensity distribution and even color point vs. emission angle. After further optimization and testing for production, the Cree XQ series of LEDs resulted. XQ LEDs are currently utilized in Cree’s AR series troffers, and they are being considered for use in other platforms. The XQ lens geometry influenced the independent development of Cree’s XB-E and XB-G high-voltage LEDs, which also have a broad intensity distribution at high efficacy, and are finding wide implementation in Cree’s omnidirectional A-lamps.

  13. A Practical Primer to LED Technology

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

    heatsink is what allows the high flux LED to generate much more light An LED (Light Emitting Diode) consists of a chip of semiconducting material treated to create a structure...

  14. LED Watch: The Outlook for OLEDs

    Broader source: Energy.gov [DOE]

    December 2014 LED Watch: The Outlook for OLEDs James Brodrick, U.S. Department of Energy LD+A Magazine

  15. Dual LED/incandescent security fixture

    DOE Patents [OSTI]

    Gauna, Kevin Wayne

    2005-06-21T23:59:59.000Z

    A dual LED and incandescent security lighting system uses a hybrid approach to LED illumination. It combines an ambient LED illuminator with a standard incandescent lamp on a motion control sensor. The LED illuminator will activate with the onset of darkness (daylight control) and typically remain on during the course of the night ("always on"). The LED illumination, typically amber, is sufficient to provide low to moderate level lighting coverage to the wall and ground area adjacent to and under the fixture. The incandescent lamp is integrated with a motion control circuit and sensor. When movement in the field of view is detected (after darkness), the incandescent lamp is switched on, providing an increased level of illumination to the area. Instead of an "always on" LED illuminator, the LEDs may also be switched off when the incandescent lamp is switched on.

  16. LED Linear Lamps and Troffer Lighting

    Broader source: Energy.gov [DOE]

    The CALiPER program performed a series of investigations on linear LED lamps. Each report in the series covers the performance of up to 31 linear LED lamps, which were purchased in late 2012 or 2013. The first report focuses on bare lamp performance of LED T8 replacement lamps and subsequent reports examine performance in various troffers, as well as cost-effectiveness. There is also a concise guidance document that describes the findings of the Series 21 studies and provides practical advice to manufacturers, specifiers, and consumers (Report 21.4: Summary of Linear (T8) LED Lamp Testing , 5 pages, June 2014).

  17. LED Replacements for Linear Fluorescent Lamps Webcast

    Broader source: Energy.gov [DOE]

    In this June 20, 2011 webcast on LED products marketed as replacements for linear fluorescent lamps, Jason Tuenge of the Pacific Northwest National Laboratory (PNNL) discussed current Lighting...

  18. LED Street Lighting Conversion Workshop Presentations

    Broader source: Energy.gov [DOE]

    This page provides links to the presentations given at the National League of Cities Mobile Workshop, LED Street Lighting Conversion: Saving Your Community Money, While Improving Public Safety,...

  19. Sandia National Laboratories: high-brightness LED

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

    Partnership, Research & Capabilities, Solid-State Lighting Solid state lighting (SSL), which uses light-emitting diodes (LEDs), has the potential to be 10 times more energy...

  20. Sandia National Laboratories: efficient LED lighting

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

    Partnership, Research & Capabilities, Solid-State Lighting Solid state lighting (SSL), which uses light-emitting diodes (LEDs), has the potential to be 10 times more energy...

  1. Challenges in LED Research and Development

    Broader source: Energy.gov [DOE]

    View the video about LED lighting technology, where it is headed, and the DOE’s role in its continued R&D.

  2. Municipal Consortium LED Street Lighting Workshop Presentations...

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

    Controls Norma Isahakian, City of Los Angeles Bureau of Street Lighting San Jose's "Smart" LED Streetlights: Controlled Amy Olay, City of San Jose Adaptive Lighting Controls...

  3. Today LED Holiday Lights, Tomorrow the World?

    SciTech Connect (OSTI)

    Gordon, Kelly L.

    2004-12-20T23:59:59.000Z

    This article for The APEM Advantage, the quarterly newsletter of the Association of Professional Energy Managers (APEM) describes the recent increase in the popularity of light emitting diode (LED) lighting and compares LED light output with that of incandescent and compact fluorescent lighting.

  4. Locally Led Conservation The Local Work Group

    E-Print Network [OSTI]

    Grants ­ Conservation Stewardship Program ­ Environmental Quality Incentive Program ­ Farm & Ranch Lands1 Locally Led Conservation & The Local Work Group Mark Habiger NRCS #12;2 What Is "Locally Led Conservation"? · Community Stakeholders ­ 1. Assessing their natural resource conservation needs ­ 2. Setting

  5. LED Light Sources for Projection Display Applications

    E-Print Network [OSTI]

    Palffy-Muhoray, Peter

    LED Light Sources for Projection Display Applications By Chenhui Peng 04-13-2012 #12;Outline · 1. · The first practical LED is in red color and it is made with gallium arsenide (GaAs). 4http://en.wikipedia.org/wiki/Light with holes and release energy in the form of photons. 5http://en.wikipedia.org/wiki/Light-emitting_diode #12

  6. Financing Guidance for LED Street Lighting Programs

    Broader source: Energy.gov [DOE]

    Financing an LED street lighting replacement program can present a hurdle for many system owners, even if the planned transition offers very favorable economics. Replacing the existing system requires a significant budget, particularly as the scope of the program increases. Cities such as Los Angeles and Seattle have invested many millions of dollars into their (very successful) LED street lighting replacement programs.

  7. High Performance Green LEDs by Homoepitaxial

    SciTech Connect (OSTI)

    Wetzel, Christian; Schubert, E Fred

    2009-11-22T23:59:59.000Z

    This work's objective was the development of processes to double or triple the light output power from green and deep green (525 - 555 nm) AlGaInN light emitting diode (LED) dies within 3 years in reference to the Lumileds Luxeon II. The project paid particular effort to all aspects of the internal generation efficiency of light. LEDs in this spectral region show the highest potential for significant performance boosts and enable the realization of phosphor-free white LEDs comprised by red-green-blue LED modules. Such modules will perform at and outperform the efficacy target projections for white-light LED systems in the Department of Energy's accelerated roadmap of the SSL initiative.

  8. An LED pulser for measuring photomultiplier linearity

    E-Print Network [OSTI]

    Friend, M; Quinn, B

    2011-01-01T23:59:59.000Z

    A light-emitting diode (LED) pulser for testing the low-rate response of a photomultiplier tube (PMT) to scintillator-like pulses has been designed, developed, and implemented. This pulser is intended to simulate 80 ns full width at half maximum photon pulses over the dynamic range of the PMT, in order to precisely determine PMT linearity. This particular design has the advantage that, unlike many LED test rigs, it does not require the use of multiple calibrated LEDs, making it insensitive to LED gain drifts. Instead, a finite-difference measurement is made using two LEDs which need not be calibrated with respect to one another. These measurements give a better than 1% mapping of the response function, allowing for the testing and development of particularly linear PMT bases.

  9. 130 LPW 1000 Lm Warm White LED for Illumination

    SciTech Connect (OSTI)

    Soer, Wouter

    2012-06-14T23:59:59.000Z

    An illumination-grade warm-white LED, having correlated color temperature (CCT) between 2700 and 3500 K and capable of producing 1000 lm output at over 130 lm/W at room temperature, has been developed in this program. The high-power warm-white LED is an ideal source for use in indoor and outdoor lighting applications. Over the two year period, we have made the following accomplishments: • Developed a low-cost high-power white LED package and commercialized a series of products with CCT ranging from 2700 to 5700 K under the product name LUXEON M; • Demonstrated a record efficacy of 124.8 lm/W at a flux of 1023 lm, CCT of 3435 K and color rendering index (CRI) over 80 at room temperature in the productized package; • Demonstrated a record efficacy of 133.1 lm/W at a flux of 1015 lm, CCT of 3475 K and CRI over 80 at room temperature in an R&D package. The new high-power LED package is a die-on-ceramic surface mountable LED package. It has four 2 mm2 InGaN pump dice, flip-chip attached to a ceramic submount in a 2x2 array configuration. The submount design utilizes a design approach that combines a high-thermal- conductivity ceramic core for die attach and a low-cost and low-thermal-conductivity ceramic frame for mechanical support and as optical lens carrier. The LED package has a thermal resistance of less than 1.25 K/W. The white LED fabrication also adopts a new batch level (instead of die-by-die) phosphor deposition process with precision layer thickness and composition control, which provides not only tight color control, but also low cost. The efficacy performance goal was achieved through the progress in following key areas: (1) high-efficiency royal blue pump LED development through active region design and epitaxial growth quality improvement (funded by internal programs); (2) improvement in extraction efficiency from the LED package through improvement of InGaN-die-level and package-level optical extraction efficiency; and (3) improvement in phosphor system efficiency by improving the lumen equivalent (LE) and phosphor package efficiency (PPE) through improvement in phosphor-package interactions. The high-power warm-white LED product developed has been proven to have good reliability through extensive reliability tests. The new kilo-lumen package has been commercialized under the product name LUXEON M. As of the end of the program, the LUXEON M product has been released in the following CCT/CRI combinations: 3000K/70, 4000K/70, 5000K/70, 5700K/70, 2700K/80, 3000K/80 and 4000K/80. LM-80 tests for the products with CCTs of 4000 K and higher have reached 8500 hours, and per IESNA TM-21-11 have established an L70 lumen maintenance value of >51,000 hours at A drive current and up to 120 °C board temperature.

  10. Studies of high temperature ternary phases in mixed-metal-rich early transition metal sulfide and phosphide systems

    SciTech Connect (OSTI)

    Marking, G.A.

    1994-01-04T23:59:59.000Z

    Investigations of ternary mixed early transition metal-rich sulfide and phosphide systems resulted in the discovery of new structures and new phases. A new series of Zr and Hf - group V transition metal - sulfur K-phases was synthesized and crystallographically characterized. When the group V transition metal was Nb or Ta, the unit cell volume was larger than any previously reported K-phase. The presence of adventitious oxygen was determined in two K-phases through a combination of neutron scattering and X-ray diffraction experiments. A compound Hf{sub 10}Ta{sub 3}S{sub 3} was found to crystallize in a new-structure type similar to the known gamma brasses. This structure is unique in that it is the only reported {open_quotes}stuffed{close_quotes} gamma-brass type structure. The metal components, Hf and Ta, are larger in size and more electropositive than the metals found in normal gamma brasses (e.g. Cu and Zn) and because of the larger metallic radii, sulfur can be incorporated into the structure where it plays an integral role in stabilizing this phase relative to others. X-ray single-crystal, X-ray powder and neutron powder refinements were performed on this structure. A new structure was found in the ternary Nb-Zr-P system which has characteristics in common with many known early transition metal-rich sulfides, selenides, and phosphides. This structure has the simplest known interconnection of the basic building blocks known for this structural class. Anomalous scattering was a powerful tool for differentiating between Zr and Nb when using Mo K{alpha} X-radiation. The compounds ZrNbP and HfNbP formed in the space group Prima with the simple Co{sub 2}Si structure which is among the most common structures found for crystalline solid materials. Solid solution compounds in the Ta-Nb-P, Ta-Zr-P, Nb-Zr-P, Hf-Nb-P, and Hf-Zr-S systems were crystallographically characterized. The structural information corroborated ideas about bonding in metal-rich compounds.

  11. High Power UV LED Industrial Curing Systems

    SciTech Connect (OSTI)

    Karlicek, Robert, F., Jr; Sargent, Robert

    2012-05-14T23:59:59.000Z

    UV curing is a green technology that is largely underutilized because UV radiation sources like Hg Lamps are unreliable and difficult to use. High Power UV LEDs are now efficient enough to replace Hg Lamps, and offer significantly improved performance relative to Hg Lamps. In this study, a modular, scalable high power UV LED curing system was designed and tested, performing well in industrial coating evaluations. In order to achieve mechanical form factors similar to commercial Hg Lamp systems, a new patent pending design was employed enabling high irradiance at long working distances. While high power UV LEDs are currently only available at longer UVA wavelengths, rapid progress on UVC LEDs and the development of new formulations designed specifically for use with UV LED sources will converge to drive more rapid adoption of UV curing technology. An assessment of the environmental impact of replacing Hg Lamp systems with UV LED systems was performed. Since UV curing is used in only a small portion of the industrial printing, painting and coating markets, the ease of use of UV LED systems should increase the use of UV curing technology. Even a small penetration of the significant number of industrial applications still using oven curing and drying will lead to significant reductions in energy consumption and reductions in the emission of green house gases and solvent emissions.

  12. LED Lighting Facts | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED Lighting Facts LED

  13. Decisions that led to Y-12

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

    German physicists Otto Hahn and Fritz Strass- mann's claim that they had achieved nuclear fission. He led a team that included Alfred O. C. Nier who was an expert on mass...

  14. LED Essentials- Technology, Applications, Advantages, Disadvantages

    Broader source: Energy.gov [DOE]

    On October 11, 2007, Kevin Dowling, VP of Innovation for Philips Solid-State Lighting Solutions, presented a broad introduction to LED technology, and discussed the technology status, advantages...

  15. LED Color Stability: 10 Important Questions

    Broader source: Energy.gov [DOE]

    This April 15, 2014 webinar examined the causes of color shift, and took a look at existing metrics used to describe color shift/color stability in LED lighting. The lumen maintenance lifetime of...

  16. Text-Alternative Version LED Lighting Forecast

    Broader source: Energy.gov [DOE]

    The DOE report Energy Savings Forecast of Solid-State Lighting in General Illumination Applications estimates the energy savings of LED white-light sources over the analysis period of 2013 to 2030....

  17. LEDS GP Success Story: Fostering Coordinated LEDS Support in Kenya (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-03-01T23:59:59.000Z

    The LEDS Global Partnership (LEDS GP) strives to advance climate-resilient, low-emission development through catalyzing collaboration, information exchange, and action on the ground. The Government of Kenya is a key LEDS GP member and offers an inspiring example of how LEDS GP is having an impact globally. The 2012 LEDS Collaboration in Action workshop in London provided an interactive space for members to share experiences on cross-ministerial LEDS leadership and to learn about concrete development impacts of LEDS around the world. Inspired by these stories, the Kenya's Ministry of State for Planning, National Development and Vision 2030 (MPND) began to collaborate closely with the Ministry of Environment and Mineral Resources to create strong links between climate change action and development in the country, culminating in the integration of Kenya's National Climate Change Action Plan and the country's Medium Term Development Plan.

  18. Pittsburgh LED Street Lighting Research Project Performance Criteria

    Broader source: Energy.gov [DOE]

    A Pittsburgh LED Street Lighting Research Project document on Technical and Aesthetic Performance for Business District LED Lighting.

  19. Mixed oxide solid solutions

    DOE Patents [OSTI]

    Magno, Scott (Dublin, CA); Wang, Ruiping (Fremont, CA); Derouane, Eric (Liverpool, GB)

    2003-01-01T23:59:59.000Z

    The present invention is a mixed oxide solid solution containing a tetravalent and a pentavalent cation that can be used as a support for a metal combustion catalyst. The invention is furthermore a combustion catalyst containing the mixed oxide solid solution and a method of making the mixed oxide solid solution. The tetravalent cation is zirconium(+4), hafnium(+4) or thorium(+4). In one embodiment, the pentavalent cation is tantalum(+5), niobium(+5) or bismuth(+5). Mixed oxide solid solutions of the present invention exhibit enhanced thermal stability, maintaining relatively high surface areas at high temperatures in the presence of water vapor.

  20. Research on optimization of cooling structure of LED element (The 2nd report)

    SciTech Connect (OSTI)

    Kobayashi, T.; Sakate, Y. [Department of Electronics and Control Engineering, Tsuyama National College of Technology, Okayama (Japan); Hashimoto, R. [Collaborative Research Center, Hiroshima University, Hiroshima (Japan); Takashina, T. [International Industry Academia Collaboration Division, Hiroshima University, Hiroshima (Japan); Kanematsu, H. [Department of Materials Science and Engineering, Suzuka National College of Technology, Mie (Japan); Utsumi, Y. [Laboratory of Advanced Science and Technology for Industry, University of Hyogo, Hyogo (Japan)

    2014-02-20T23:59:59.000Z

    This report shows a design guideline on the parts dimension of LED light bulb for heat transfer. LED light bulb is popular owing to the high efficiency and long life. However, LED element is a point heat source. Therefore, LED light bulb has some problems about heat transfer when it is used for lighting. It sometimes causes deterioration by the raise of local temperature, resulting in lowering of efficiency and shorter life. Thus the thermal analysis focused on the number of element, all parts thickness, length, and radiant heat was studied, as systematic report on the points has not been found. In this report, heat radiation was taken into account in the thermal analysis in addition to natural heat convection. Furthermore the temperature of a heat sink model for LED light bulb was measured with thermocouples and thermo-viewer to verify the calculation. The emissivity of aluminum used for the calculation was 0.4. As the result of analysis, it was found that the maximum temperature was mainly influenced by ring length, ring diameter and disk thickness as a design guideline. Concretely, longer length, larger diameter and thicker disk gave lower temperature of LED element. The temperatures of the best and worst model were around 70 °C and 120 °C respectively in the above condition. The temperatures calculated were consistent with those in experiment.

  1. LED Lighting Forecast | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED Lighting Facts

  2. LED Outdoor Area Lighting Fact Sheet

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED LightingOutdoor Area

  3. What led to the pervasiveness of hybrids between Cx. pipiens and Cx. molestus in

    E-Print Network [OSTI]

    What led to the pervasiveness of hybrids between Cx. pipiens and Cx. molestus in North America populations with a few hybrid individuals, as well as populations with pure Cx. pipiens signatures and populations with a mix of pure Cx. pipiens and pure Cx. molestus signatures (Fig. 2). Indeed, previous

  4. LED structure with enhanced mirror reflectivity

    DOE Patents [OSTI]

    Bergmann, Michael; Donofrio, Matthew; Heikman, Sten; Schneider, Kevin S; Haberern, Kevin W; Edmond, John A

    2014-04-01T23:59:59.000Z

    Embodiments of the present invention are generally related to LED chips having improved overall emission by reducing the light-absorbing effects of barrier layers adjacent mirror contacts. In one embodiment, a LED chip comprises one or more LEDs, with each LED having an active region, a first contact under the active region having a highly reflective mirror, and a barrier layer adjacent the mirror. The barrier layer is smaller than the mirror such that it does not extend beyond the periphery of the mirror. In another possible embodiment, an insulator is further provided, with the insulator adjacent the barrier layer and adjacent portions of the mirror not contacted by the active region or by the barrier layer. In yet another embodiment, a second contact is provided on the active region. In a further embodiment, the barrier layer is smaller than the mirror such that the periphery of the mirror is at least 40% free of the barrier layer, and the second contact is below the first contact and accessible from the bottom of the chip.

  5. LEDs for Energy Efficient Greenhouse Lighting

    E-Print Network [OSTI]

    Singh, Devesh; Meinhardt-Wollweber, Merve; Roth, Bernhard

    2014-01-01T23:59:59.000Z

    Light energy is an important factor for plant growth. In regions where the natural light source, i.e. solar radiation, is not sufficient for growth optimization, additional light sources are being used. Traditional light sources such as high pressure sodium lamps and other metal halide lamps are not very efficient and generate high radiant heat. Therefore, new sustainable solutions should be developed for energy efficient greenhouse lighting. Recent developments in the field of light source technologies have opened up new perspectives for sustainable and highly efficient light sources in the form of light-emitting diodes, i.e. LEDs, for greenhouse lighting. This review focuses on the potential of LEDs to replace traditional light sources in the greenhouse. In a comparative economic analysis of traditional vs. LED lighting, we show that the introduction of LEDs allows reduction of the production cost of vegetables in the long-run of several years, due to the high energy efficiency, low maintenance cost and lon...

  6. Sustainable LED Fluorescent Light Replacement Technology

    SciTech Connect (OSTI)

    None

    2011-06-30T23:59:59.000Z

    Ilumisys and the National Center for Manufacturing Sciences (NCMS) partnered on a three-year project awarded by the United States (U.S.) Department of Energy (DOE), to quantify the impacts of LED lamps, incandescent lamps and fluorescent benchmark lamps over a product lifecycle – i.e. to develop a sustainable design and manufacturing strategy that addresses product manufacturing, use, recycling and disposal scenarios for LED-based lighting. Based on the knowledge gained from extensive product tear-down studies of fluorescent and screw-in lighting products, lifecycle assessment tools, and accelerated lifecycle testing protocols, an interactive Sustainable LED Design Guide has been developed to aid architectural and lighting designers and engineers in making design decisions that consider three important environmental impacts (greenhouse gas emissions, energy use and mercury emission) across all phases of the life of an LED lighting product. Critical information developed for the lifecycle analysis and product feature comparisons is the useful life of the lighting product as well as its performance. The Design Guide is available at www.ncms.org, and was developed based on operational and durability testing of a variety of lighting products including power consumption, light output, and useful life of a lamp in order to allow a more realistic comparison of lamp designs. This report describes the main project tasks, results and innovative features of the lifecycle assessment (LCA)-based design tools, and the key considerations driving the sustainable design of LED lighting systems. The Design Guide incorporates the following three novel features for efficiently evaluating LED lighting features in value-chains: • Bill-of-Materials (BOM) Builder – Designers may import process data for each component and supply functional data for the product, including power, consumption, lumen output and expected useful life. • Environmental Impact Review – Designs are comparable across lifecycle phases, subsystems, and environmental impact category, and can be normalized to a userdefined functional unit. • Drill-down Review – These provide an indepth look at individual lamp designs with the ability to review across subsystem or lifecycle phase.

  7. Low-Cost Illumination-Grade LEDs

    SciTech Connect (OSTI)

    Epler, John

    2013-08-31T23:59:59.000Z

    Solid State Lighting is a cost-effective, energy-conserving technology serving a rapidly expand- ing multi-billion dollar market. This program was designed to accelerate this lighting revolution by reducing the manufacturing cost of Illumination-Grade LEDs. The technical strategy was to investigate growth substrate alternatives to standard planar sapphire, select the most effective and compatible option, and demonstrate a significant increase in Lumen/$ with a marketable LED. The most obvious alternate substrate, silicon, was extensively studied in the first two years of the program. The superior thermal and mechanical properties of Si were expected to improve wavelength uniformity and hence color yield in the manufacture of high-power illumination- grade LEDs. However, improvements in efficiency and epitaxy uniformity on standard c-plane sapphire diminished the advantages of switching to Si. Furthermore, the cost of sapphire decreased significantly and the cost of processing Si devices using our thin film process was higher than expected. We concluded that GaN on Si was a viable technology but not a practical option for Philips Lumileds. Therefore in 2012 and 2013, we sought and received amendments which broadened the scope to include other substrates and extended the time of execution. Proprietary engineered substrates, off-axis (non-c-plane) sapphire, and c-plane patterned sapphire substrates (PSS) were all investigated in the final 18 months of this program. Excellent epitaxy quality was achieved on all three candidates; however we eliminated engineered substrates and non-c-plane sapphire because of their higher combined cost of substrate, device fabrication and packaging. Ultimately, by fabricating a flip-chip (FC) LED based upon c-plane PSS we attained a 42% reduction in LED manufacturing cost relative to our LUXEON Rebel product (Q1-2012). Combined with a flux gain from 85 to 102 Lm, the LUXEON Q delivered a 210% increase in Lm/$ over this time period. The technology was commercialized in our LUXEON Q product in Sept., 2013. Also, the retention of the sapphire increased the robustness of the device, enabling sales of low-cost submount-free chips to lighting manufacturers. Thus, blue LED die sales were initiated in the form of a PSS-FC in February, 2013.

  8. Series Input Modular Architecture for Driving Multiple LEDs

    E-Print Network [OSTI]

    , where each cell drives four 700 mA LEDs. Keywords ­ solid-state lighting, light emitting diodes, LED have been achieved over the past decade in solid state light emitting diodes (LEDs), leading to high

  9. Demonstration Assessment of Light Emitting Diode (LED) Street...

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

    Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Final Report Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Final Report This...

  10. Demonstration Assessment of Light-Emitting Diode (LED) Freezer...

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

    Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case Lighting Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case Lighting This document is a report...

  11. (Expired) Nationwide Limited Public Interest Waiver for LED Lighting...

    Energy Savers [EERE]

    (Expired) Nationwide Limited Public Interest Waiver for LED Lighting and HVAC Units: February 11, 2010 (Expired) Nationwide Limited Public Interest Waiver for LED Lighting and HVAC...

  12. Energy Department Announces New University-Led Projects to Create...

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

    University-Led Projects to Create More Efficient, Lower Cost Concentrating Solar Power Systems Energy Department Announces New University-Led Projects to Create More Efficient,...

  13. Research Led by Sandia Reveals Leading-Edge Erosion Significantly...

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

    Research Led by Sandia Reveals Leading-Edge Erosion Significantly Reduces Wind Turbine Performance Research Led by Sandia Reveals Leading-Edge Erosion Significantly Reduces Wind...

  14. Mixing it up - Measuring diffusion in supercooled liquid solutions...

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

    Mixing it up - Measuring diffusion in supercooled liquid solutions of methanol and ethanol at temperatures near the glass Mixing it up - Measuring diffusion in supercooled liquid...

  15. LED North America - Energy Innovation Portal

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 - -/e),,s - 1 2 3 4 5 6 7 8 9LDRD, What doesLED

  16. White LED with High Package Extraction Efficiency

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem Not Found Item Not Found The item youTheWSRC-TR-97-0100WHITE LED WITH HIGH PACKAGE

  17. SemiLEDs | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f < RAPID‎ |Rippey JumpAir JumpCalifornia | OpenSelawik|SemiLEDs Jump

  18. SunLed Technologies | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries PvtStratosolar Jump to: navigation,SunElectra Jump to: navigation,SunLed

  19. Recessed LED Downlights | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin of ContaminationHubs+18, 2012 Qualified11Department ofMeetingSynthetic DieselRecessed LED

  20. Demonstration of LED Retrofit Lamps at the Smithsonian American Art Museum, Washington, DC

    SciTech Connect (OSTI)

    Miller, Naomi J.; Rosenfeld, Scott M.

    2012-06-22T23:59:59.000Z

    This report documents observations and results obtained from a lighting demonstration project conducted under the U.S. Department of Energy GATEWAY Solid-State Lighting (SSL) Technology Demonstration Program at the Smithsonain American Art Museum in Washington, DC. LED Lamp samples were tested in the museum workshop, temporarily installed in a gallery for feedback, and ultimately replaced all traditional incandescent lamps in one gallery of modernist art at the American Art Museum and partially replacing lamps in two galleries at the Musesum's Renwick Gallery. This report describes the selection and testing process, technology challenges, perceptions, economics, energy use, and mixed results of usign LED replacement lamps in art galleries housing national treasures.

  1. New and Underutilized Technology: High Bay LED Lighting

    Broader source: Energy.gov [DOE]

    The following information outlines key deployment considerations for high bay LED lighting within the Federal sector.

  2. Text-Alternative Version: LED Essentials- Technology, Applications, Advantages, Disadvantages

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the LED Essentials - Technology, Applications, Advantages, Disadvantages webcast.

  3. Microscopic, electrical and optical studies on InGaN/GaN quantum wells based LED devices

    SciTech Connect (OSTI)

    Mutta, Geeta Rani; Venturi, Giulia; Castaldini, Antonio; Cavallini, Anna [Department of Physics and Astronomy, University of Bologna, Viale Carlo Berti Pichat 6/II, 40127 Bologna (Italy); Meneghini, Matteo; Zanoni, Enrico; Meneghesso, Gaudenzio [University of Padova, Department of Information Engineering, via Gradenigo 6/B, Padova 35131 (Italy); Zhu, Dandan; Humphreys, Colin [Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ (United Kingdom)

    2014-02-21T23:59:59.000Z

    We report here on the micro structural, electronic and optical properties of a GaN-based InGaN/GaN MQW LED grown by the MOVPE method. The present study shows that the threading dislocations present in these LED structures are terminated as V pits at the surface and have an impact on the electrical and optical activity of these devices. It has been pointed that these dislocations were of edge, screw and mixed types. EBIC maps suggest that the electrically active defects are screw and mixed dislocations and behave as nonradiative recombinant centres.

  4. Regenerative braking on bicycles to power LED safety flashers

    E-Print Network [OSTI]

    Collier, Ian M

    2005-01-01T23:59:59.000Z

    This work develops a method for capturing some of the kinetic energy ordinarily lost during braking on bicycles to power LED safety flashers. The system is designed to eliminate: (a) battery changing in popular LED flashers, ...

  5. Building highly efficient LEDs in the yellow-green spectrum

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    Argonne and Purdue researchers are peering deep into the atomic structure and composition of LED lights in order to build highly efficient LEDs in the yellow-green spectrum.

  6. EECBG Success Story: Small Nebraska Town Welcomes LEDs and Energy...

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

    historic square, built in the 1850's, is about to become home to something new: LED lights. Learn more. Addthis Related Articles Tecumseh is installing 95 new LED light fixtures...

  7. LED Manufacturing Process Modifications Will Boost Quality and

    E-Print Network [OSTI]

    2012 The Issue Highly energyefficient LightEmitting Diode (LED) lighting products have made great process that will enable LED manufacturers to produce higher quality, energyefficient products at lower

  8. LEDs Go Ivy League: Princeton’s Dillon Gymnasium

    Broader source: Energy.gov [DOE]

    View the video about LED lighting in Dillon Gymnasium, a focal point of sports and recreation at Princeton since 1947. William Evans discusses measurable benefits of LED lighting in the gym and...

  9. Text-Alternative Version: Challenges in LED Research and Development

    Broader source: Energy.gov [DOE]

    Narrator: LEDs have made remarkable progress in the past decade and gained a strong foothold in the US marketplace. In 2012, LED lighting saved an estimated 71 trillion BTUs, equivalent to annual...

  10. Net weekly variation of vertical temperature structure in the upper ocean layers (Autumn, North Atlantic)

    E-Print Network [OSTI]

    Gilcrest, Robert A

    1957-01-01T23:59:59.000Z

    in Halstead's Figure 3 (tigure 5). Cloud cover affects both the incoming short-wave and out- going long~vs radiation. The cloud observations of the ship reports give the total oloud oover in tenths, the number of tenths of low oloud, and the type of m... Depths (after Leipper and Adams? 1952) Temperatures at Selected Depths (Smoothed) Model Temperature Profile Relation Betveen Mixed-layer Depth and Surface Temperature at 50oR l5oW Fraotional Transmission of Radiation Through led. t Air M?ss Effect...

  11. Text-Alternative Version: LED Replacements for Linear Fluorescent Lamps

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "LED Replacements for Linear Fluorescent Lamps" webcast, held June 20, 2011.

  12. Text-Alternative Version: LEDs for Interior Office Applications

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the LEDs for Interior Office Applications webcast, held March 18, 2010.

  13. Text-Alternative Version: Evaluating LED Street Lighting Solutions

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the Evaluating LED Street Lighting Solutions webcast, held July 20, 2010.

  14. Two-stage Ignition as an Indicator of Low Temperature Combustion in a Late Injection Pre-mixed Compression Ignition Control Strategy

    E-Print Network [OSTI]

    Bittle, Joshua

    2011-02-22T23:59:59.000Z

    cool-flame is not observed. By controlling initial conditions (pressure, temperature, and composition), the creation and duration of the cool-flame event is predictable. Further, the effect that injection timing and the exhaust gas recirculation level...

  15. Mann LED Elevator Ligh ng: ECI Savings Table Cost (billed)

    E-Print Network [OSTI]

    Lipson, Michal

    the elevators, deter mined an LED replace ment lamp for the ex is ng halogen lamps, cal culated a cost benefitMann LED Elevator Ligh ng: ECI Savings Table Utility Historical Energy Use (MMBtu) Est. FY 2012,000 2 Energy Conservation Initiative (ECI) Project Summary Mann LED Elevator Ligh ng, Facility 1027 Mann

  16. Cree Sets New Benchmarks for LED Efficacy and Brightness

    Broader source: Energy.gov [DOE]

    Cree has successfully created a cool white LED prototype that delivers 107 lm/W at 350mA. This achievement builds on the Cree EZBright® LED chip platform, developed in part with prior funding support from DOE. Cree made the prototype LED under their DOE project focused on developing LED chips incorporating photonic crystal elements for improved light extraction and novel package technology for higher down-conversion efficiency compared to conventional LEDs. Based on a 1 millimeter-square chip, the new prototype LED produces white light with a CCT of 5500K and a CRI of 73. Integration of four of these prototype LEDs can produce luminous flux of more than 450 lumens.

  17. Economizer Control Using Mixed Air Enthalpy

    E-Print Network [OSTI]

    Feng, J.; Liu, M.; Pang, W.

    2007-01-01T23:59:59.000Z

    economizer is db-temperature based economizer. Table7. Economizer Operation Testing Period: April.3 rd ~Aug. 22 th ,2007 Temperature- based Economizer Mixed-air enthalpy economizer Operation hours 888 1251 Energy saving - 15.7% 6...

  18. Low-temperature transport properties of the mixed-valence semiconductor Ru{sub 0.5}Pd{sub 0.5}Sb{sub 3}

    SciTech Connect (OSTI)

    Nolas, G.S. [Research and Development Division, Marlow Industries, Dallas, Texas 75238 (United States)] [Research and Development Division, Marlow Industries, Dallas, Texas 75238 (United States); Harris, V.G.; Tritt, T.M. [Materials Physics Branch, Naval Research Laboratory, Washington, DC 20375 (United States)] [Materials Physics Branch, Naval Research Laboratory, Washington, DC 20375 (United States); Slack, G.A. [Department of Physics, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)] [Department of Physics, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    1996-12-01T23:59:59.000Z

    We have measured the transport properties of Ru{sub 0.5}Pd{sub 0.5}Sb{sub 3} from 300 down to 4 K and compared them to those of the binary-skutterudite antimonides. In particular, the lattice thermal conductivity of this compound is substantially lower than that of CoSb{sub 3} and IrSb{sub 3}. This is attributed to the mixed-valency of ruthenium in this compound. Using near-edge extended absorption fine structure analysis, it is observed that ruthenium in this compound is in the Ru{sup 4+}- and Ru{sup 2+}-valence states in approximately equal proportions. The potential for thermoelectric applications of this material is also discussed. {copyright} {ital 1996 American Institute of Physics.}

  19. Neutrino Mixing

    E-Print Network [OSTI]

    Carlo Giunti; Marco Laveder

    2004-10-01T23:59:59.000Z

    In this review we present the main features of the current status of neutrino physics. After a review of the theory of neutrino mixing and oscillations, we discuss the current status of solar and atmospheric neutrino oscillation experiments. We show that the current data can be nicely accommodated in the framework of three-neutrino mixing. We discuss also the problem of the determination of the absolute neutrino mass scale through Tritium beta-decay experiments and astrophysical observations, and the exploration of the Majorana nature of massive neutrinos through neutrinoless double-beta decay experiments. Finally, future prospects are briefly discussed.

  20. Radioactive mixed waste disposal

    SciTech Connect (OSTI)

    Jasen, W.G.; Erpenbeck, E.G.

    1993-02-01T23:59:59.000Z

    Various types of waste have been generated during the 50-year history of the Hanford Site. Regulatory changes in the last 20 years have provided the emphasis for better management of these wastes. Interpretations of the Atomic Energy Act of 1954 (AEA), the Resource Conservation and Recovery Act of 1976 (RCRA), and the Hazardous and Solid Waste Amendments (HSWA) have led to the definition of radioactive mixed wastes (RMW). The radioactive and hazardous properties of these wastes have resulted in the initiation of special projects for the management of these wastes. Other solid wastes at the Hanford Site include low-level wastes, transuranic (TRU), and nonradioactive hazardous wastes. This paper describes a system for the treatment, storage, and disposal (TSD) of solid radioactive waste.

  1. To Bridge LEDs' Green Gap, Scientists Think Small

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

    where LED efficiency plunges, simulations at the U.S. Department of Energy's National Energy Research Scientific Computing Center (NERSC) have shown. Using NERSC's Cray XC30...

  2. LED Luminaire Lifetime: Recommendations for Testing and Reporting

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

    product life, and many relied on the gradual lumen depreciation of the LED (light-emitting diode) source as the best indicator- resulting, on occasion, in unrealistic claims...

  3. LED Provides Effective and Efficient Parking Area Lighting at...

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

    White Light Options for Parking Area Lighting Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Final Report Guide to FEMP-Designated Parking Lot...

  4. The City of Los Angeles LED Streetlight Program

    Broader source: Energy.gov [DOE]

    View the video about the Los Angeles LED streetlight program, featuring an interview with City of Los Angeles Bureau of Street Lighting Director, Ed Ebrahimian.

  5. ORNL-led team demonstrates desalination with nanoporous graphene...

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

    Communications 865.576.6448 ORNL-led team demonstrates desalination with nanoporous graphene membrane Researchers created nanopores in graphene (red, and enlarged in the circle...

  6. Article Published on LED Lumen Maintenance and Light Loss Factors...

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

    of a comprehensive lifetime rating - as well as the problematic relationship between SSL lifetime and lumen maintenance - determining an appropriate LLD factor for LED products...

  7. CBEA LED Site Lighting Specification - Version 1.3, Released...

    Energy Savers [EERE]

    Applications Outdoor Area Lighting Home About the Solid-State Lighting Program R&D Program Market-Based Programs SSL Basics Using LEDs Information Resources Financial Opportunities...

  8. Lighting the Great Outdoors: LEDs in Exterior Applications

    SciTech Connect (OSTI)

    Cook, Tyson D. S.; Bryan, Mary M.; Kinzey, Bruce R.; Myer, Michael

    2008-08-17T23:59:59.000Z

    Recent progress in the development of white light LEDs promises great impact by opening up the huge potential for LED illumination in new areas. One such area is general illumination for exterior applications. For example, there are an estimated combined 60.5 million roadway and parking installations in the U.S. These lights account for an estimated 53.3 TWh of electricity usage annually -- nearly 7% of all lighting. If LEDs could provide the same light performance with just 25% greater efficiency, savings of over 13 TWh could be achieved. In 2007, the authors assessed emerging LED lighting technologies in a parking garage and on a city street. The purpose of these tests was to enable a utility to determine whether energy efficiency programs promoting white light LED products might be justified. The results have supported the great promise of LEDs in exterior applications, while also highlighting the barriers that continue to hinder their widespread adoption. Such barriers include 1) inconsistent product quality across manufacturers; 2) lack of key metrics for comparing LEDs to conventional sources; and 3) high upfront cost of LED luminaires compared to conventional luminaires. This paper examines these barriers, ways in which energy-efficiency programs could help to overcome them, and the potential for energy and financial savings from LED lighting in these two exterior applications.

  9. LEDs Go Ivy League: Princeton University and DOE GATEWAY Demonstrations

    Broader source: Energy.gov [DOE]

    View the video about LED lighting at Princeton University, which has dramatically reduced energy costs in a number of installations around campus. William Evans, electrical engineer, describes the...

  10. Adopting LED Technology: What Federal Facility Managers Need to Know

    Broader source: Energy.gov [DOE]

    This document describes the presentation slides for the "Adopting LED Technology: What Federal Facility Managers Need to Know" webinar that took place on September 11, 2014.

  11. Cooking Up New Nanoribbons to Make Better White LEDs | Advanced...

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

    appealing white phosphors based on LEDs. The materials combine the rare-earth element europium with aluminum oxide to form europium aluminate nanoribbons. Powders of europium oxide...

  12. Unveiling neutrino mixing and leptonic CP violation

    SciTech Connect (OSTI)

    Mena, Olga; /Fermilab

    2005-01-01T23:59:59.000Z

    We review the present understanding of neutrino masses and mixings, discussing what are the unknowns in the three family oscillation scenario. Despite the anticipated success coming from the planned long baseline neutrino experiments in unraveling the leptonic mixing sector, there are two important unknowns which may remain obscure: the mixing angle {theta}{sub 13} and the CP-phase {delta}. The measurement of these two parameters has led us to consider the combination of superbeams and neutrino factories as the key to unveil the neutrino oscillation picture.

  13. Low Cost Lithography Tool for High Brightness LED Manufacturing

    SciTech Connect (OSTI)

    Andrew Hawryluk; Emily True

    2012-06-30T23:59:59.000Z

    The objective of this activity was to address the need for improved manufacturing tools for LEDs. Improvements include lower cost (both capital equipment cost reductions and cost-ofownership reductions), better automation and better yields. To meet the DOE objective of $1- 2/kilolumen, it will be necessary to develop these highly automated manufacturing tools. Lithography is used extensively in the fabrication of high-brightness LEDs, but the tools used to date are not scalable to high-volume manufacturing. This activity addressed the LED lithography process. During R&D and low volume manufacturing, most LED companies use contact-printers. However, several industries have shown that these printers are incompatible with high volume manufacturing and the LED industry needs to evolve to projection steppers. The need for projection lithography tools for LED manufacturing is identified in the Solid State Lighting Manufacturing Roadmap Draft, June 2009. The Roadmap states that Projection tools are needed by 2011. This work will modify a stepper, originally designed for semiconductor manufacturing, for use in LED manufacturing. This work addresses improvements to yield, material handling, automation and throughput for LED manufacturing while reducing the capital equipment cost.

  14. A NEW LED-LED PORTABLE CO2 GAS SENSOR BASED ON AN INTERCHANGEABLE MEMBRANE SYSTEM FOR INDUSTRIAL APPLICATIONS

    E-Print Network [OSTI]

    Lee, Hyowon

    to oxygen scavenging [5]. High CO2 levels (10- 80 %) are desirable for foods such as meat and poultryA NEW LED-LED PORTABLE CO2 GAS SENSOR BASED ON AN INTERCHANGEABLE MEMBRANE SYSTEM FOR INDUSTRIAL APPLICATIONS Abstract A new system for CO2 measurement (0-100%) by based on a paired emitter-detector diode

  15. Lumen and Chromaticity Maintenance of LED PAR38 Lamps Operated in Steady-State Conditions

    SciTech Connect (OSTI)

    Royer, Michael P.

    2014-12-01T23:59:59.000Z

    The lumen depreciation and color shift of 38 different lamps (32 LED, 2 CFL, 1 ceramic metal halide [CMH], 3 halogen) were monitored in a specially developed automated long-term test apparatus (ALTA2) for nearly 14,000 hours. Five samples of each lamp model were tested, with measurements recorded on a weekly basis. The lamps were operated continuously at a target ambient temperature between 44°C and 45°C.

  16. LED Lights for All Occasions | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED Lighting FactsLED

  17. Team Led by Argonne National Lab Selected as DOE's Batteries...

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

    Team Led by Argonne National Lab Selected as DOE's Batteries and Energy Storage Hub On November 30, 2012 In features Energy Department Announces Team to Receive up to 120...

  18. WEBINAR: CAN LEDS PERFORM IN A PERFORMING ARTS BUILDING? | Department...

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

    the Nadine McGuire Theatre + Dance Pavilion at the University of Florida. Can LEDs render skin tones and makeup accurately in a dressing room? Can they provide the vertical...

  19. EECBG Success Story: Solar LED Light Pilot Project Illuminates...

    Energy Savers [EERE]

    courtesy of Lionel Green, Sand Mountain Reporter. A strip of new solar-powered light emitting-diode (LED) streetlights in Boaz, Alabama were installed with grant funds from the...

  20. MOF Coating a Promising Path to White LEDs

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

    (MOF); the structure was determined at Beamline 11.3.1. Coating a blue light-emitting diode (LED) with this compound readily generates white light with high luminous...

  1. Text-Alternative Version: LED Color Stability Webinar

    Broader source: Energy.gov [DOE]

    Michael Royer: All right, welcome ladies and gentleman. I'm Michael Royer of Pacific Northwest National Laboratory, and I'd like to welcome you to today's webinar on LED Color Stability, Ten...

  2. Measured Off-Grid LED Lighting System Performance

    E-Print Network [OSTI]

    Granderson, Jessica

    2009-01-01T23:59:59.000Z

    Budget: The Economics of Off-Grid Lighting for SmallA. Jacobson. 2007. "The Off-Grid Lighting Market in WesternTesting for Emerging Off-grid White-LED Illumination Systems

  3. Implementing and Sustaining Operator Led Energy Efficiency Improvements

    E-Print Network [OSTI]

    Hoyle, A.; Knight, N.; Rutkowski, M.

    2011-01-01T23:59:59.000Z

    , to significantly reduce energy consumption, the site must focus on a strategic approach which involves developing, implementing and sustaining a client specific program of energy optimization. We discuss ways of sustaining energy performance through operator led...

  4. Sandia National Laboratories: AlGaAs LEDs

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

    electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

  5. Advances in Chip Technology, Packaging Enable White LED Breakthroughs

    Broader source: Energy.gov [DOE]

    Significant advances in chip technology have enabled Cree, Inc.'s Santa Barbara Technology Center to demonstrate white LEDs with record efficacies as high as 74 lumens per watt - on par with...

  6. Laboratory Evaluation of LED T8 Replacement Lamp Products

    SciTech Connect (OSTI)

    Richman, Eric E.; Kinzey, Bruce R.; Miller, Naomi J.

    2011-05-23T23:59:59.000Z

    A report on a lab setting analysis involving LED lamps intended to directly replace T8 fluorescent lamps (4') showing light output, power, and economic comparisons with other fluorescent options.

  7. WEBINAR: LED LIGHTING IN A PERFORMING ARTS BUILDING

    Broader source: Energy.gov [DOE]

    Can LEDs render skin tones and makeup accurately in a dressing room? Can they provide the vertical footcandles in a studio to make dancers' bodies visible, or deliver acting studio lighting to...

  8. Demonstrating LED and Fiber Optic Lighting in Commissary Applications

    Broader source: Energy.gov [DOE]

    Presentation—given at the Federal Utility Partnership Working Group (FUPWG) Fall 2008 meeting—covers goals of the project and applications for light-emitting diodes (LEDs) and fiber optic lighting.

  9. af led lyskilder: Topics by E-print Network

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

    Effective Fabrication of a Solar PV Panel for LED Lighting CiteSeer Summary: Abstract Solar cells are very fragile so they need a encapsulant and encasing for protection and...

  10. White LED Benchmark of 65 Lumens Per Watt Achieved

    Broader source: Energy.gov [DOE]

    Novel chip design and the balance of multiple interrelated design parameters have enabled Cree, Inc.'s Santa Barbara Technology Center to demonstrate white LEDs with efficacies greater than 65 lumens per watt at 350 mA. The results are particularly significant because they were achieved with a pre-production prototype chip using the same package used in Cree's commercially available XLamp® 7090 high power LED, rather than a laboratory device.

  11. An Integrated Solid-State LED Luminaire for General Lighting

    SciTech Connect (OSTI)

    Kevin Dowling; Fritz Morgan Ihor Lys; Mike Datta; Bernd Keller; Thomas Yuan

    2009-03-31T23:59:59.000Z

    A strong systems approach to designing and building practical LED-based replacement lamps is lacking. The general method of taking high-performance LEDs and marrying them to standard printed circuit boards, drivers and a heat sink has fallen short of the promise of LED lighting. In this program, a top-down assessment of requirements and a bottom-up reinvention of LED sources, electronics, optics and mechanics have resulted in the highest performance lamp possible. The team, comprised of Color Kinetics, the leaders in LED lighting and Cree, the leaders in LED devices took an approach to reinvent the package, the driver and the overall form and aesthetic of a replacement source. The challenge was to create a new benchmark in LED lighting - the resultant lamp, a PAR38 equivalent, met the light output, color, color quality and efficacy marks set out in the program as well as being dimmable, which is important for market acceptance. The approach combined the use of multiple source die, a chip-on-board approach, a very efficient driver topology, the use of both direct emission and phosphor conversion, and a unique faceted optic to avoid the losses, artifacts and hotspots of lensed approaches. The integral heat sink provided a mechanical base and airflow using a chimney-effect for use in a wide variety of locations and orientations. These research results led to a much better understanding of the system effects of component level technologies. It was clear that best-of-breed sub-system results do not necessarily result in the best end result for the complete system. In doing this work, we did not neglect the practical aspects of these systems. These were not rarified results and commercially impractical but lent themselves to eventual commercial products in the marketplace. The end result - a high performance replacement lamp - will save significant energy while providing a high-quality light source.

  12. High-Efficiency Non-Polar GaN-Based LEDs

    SciTech Connect (OSTI)

    Paul Fini

    2010-11-30T23:59:59.000Z

    Inlustra Technologies with subcontractor U.C. Santa Barbara conducted a project with the principle goal of demonstrating high internal quantum efficiency blue (430 nm) and green (540nm) light emitting diodes (LEDs) on low-defect density non-polar GaN wafers. Inlustra pursued the fabrication of smooth thick a-plane and m-plane GaN films, as well as defect reduction techniques such as lateral epitaxial overgrowth (LEO) to uniformly lower dislocation density in these films. Limited free-standing wafers were produced as well. By the end of the reporting period, Inlustra had met its milestone of dislocation reduction to < 5 x 10{sup 6} cm{sup -2}. Stacking faults were still present in appreciable density ({approx} 1 x 10{sup 5} cm{sup -1}), but were not the primary focus of defect reduction since there have been no published studies establishing their detrimental effects on LED performance. Inlustra's LEO progress built a solid foundation upon which further commercial development of GaN substrates will occur. UCSB encountered multiple delays in its LED growth and fabrication efforts due to unavoidable facilities outages imposed by ongoing construction in an area adjacent to the metalorganic chemical vapor deposition (MOCVD) laboratory. This, combined with the large amount of ab initio optimization required for the MOCVD system used during the project, resulted in unsatisfactory LED progress. Although numerous blue-green photoluminescence results were obtained, only a few LED structures exhibited electroluminescence at appreciable levels. UCSB also conducting extensive modeling (led by Prof. Van de Walle) on the problem of non-radiative Auger recombination in GaN-based LED structures, which has been posited to contribute to LED efficiency 'droop' at elevated current density. Unlike previous modeling efforts, UCSB's approach was truly a first-principles ab initio methodology. Building on solid numerical foundations, the Auger recombination rates of In{sub x}Ga{sub 1-x}N alloys were calculated from first-principles density-functional and many-body-perturbation theory. The differing mechanisms of inter- and intra-band recombination were found to affect different parts of the emission spectrum. In the blue to green spectral region and at room temperature the Auger coefficient was calculated to be as large as 2 x 10{sup -30} cm{sup 6} s{sup -1}; in the infrared it is even larger. These results indicated that Auger recombination may be responsible for the loss of quantum efficiency that affects InGaN-based light emitters, whether on non-polar or polar crystal planes.

  13. High-Power Warm-White Hybrid LED Package for Illumination

    SciTech Connect (OSTI)

    Soer, Wouter

    2013-09-19T23:59:59.000Z

    In this project, an integrated warm-white hybrid light engine was developed. The hybrid approach involves combining phosphor-converted off-white InGaN LEDs and direct-emitting red AlInGaP LEDs in a single light engine to achieve high efficacy together with high color rendering index. We developed and integrated technology improvements in InGaN and AlInGaP die technology, phosphor technology, package architecture and encapsulation, to realize a hybrid warm-white LED package with an efficacy of 140 lm/W at a correlated color temperature of 3000K and a color rendering index of 90, measured under representative operating conditions. This efficacy is 26% higher than the best warm-white LEDs of similar specification that are commercially available at the end of the project. Since the InGaN- and AlInGaP-based LEDs used in the hybrid engine show different behavior as a function of current and temperature, a control system needs to be in place to ensure a stable color point over all operating conditions. In this project, we developed an electronic control circuit that is fully integrated into the light engine in such a way that the module can simply be driven by a conventional single-channel driver. The integrated control circuit uses a switch-mode boost converter topology to control the LED drive currents based on the temperature and the input current of the light engine. A color control performance of 5 SDCM was demonstrated, and improvement to 3 SDCM is considered well within reach. The combination of high efficacy and ease of integration with existing single-channel drivers is expected to facilitate the adoption of the hybrid technology and accelerate the energy savings associated with solid-state lighting. In the product commercialization plan, downlights and indirect-lit troffers have been selected as the first target applications for this product concept. Fully functional integrated prototypes have been developed for both applications, and the business case evaluation is ongoing as of the end of the project.

  14. Advanced method for increasing the efficiency of white light quantum dot LEDs

    SciTech Connect (OSTI)

    Duty, Chad E [ORNL; Bennett, Charlee J C [ORNL; Sabau, Adrian S [ORNL; Jellison Jr, Gerald Earle [ORNL; Boudreaux, Philip R [ORNL; Walker, Steven C [ORNL; Ott, Ronald D [ORNL

    2011-01-01T23:59:59.000Z

    Covering a light-emitting diode (LED) with quantum dots (QDs) can produce a broad spectrum of white light. However, current techniques for applying QDs to LEDs suffer from a high density of defects and a non-uniform distribution of QDs, which, respectively, diminish the efficiency and quality of emitted light. Oak Ridge National Laboratory (ORNL) has the unique capability to thermally anneal QD structures at extremely high power densities for very short durations. This process, called pulse thermal processing (PTP), reduces the number of point defects while maintaining the size and shape of the original QD nanostructure. Therefore, the efficiency of the QD wavelength conversion layer is improved without altering the emission spectrum defined by the size distribution of theQD nanoparticles. The current research uses a thermal model to predict annealing temperatures during PTP and demonstrates up to a 300% increase in photoluminescence for QDs on passive substrates.

  15. An LED-based Flasher System for VERITAS

    E-Print Network [OSTI]

    Hanna, D; McCutcheon, M; Nikkinen, L; 10.1016/j.nima.2009.10.107

    2009-01-01T23:59:59.000Z

    We describe a flasher system designed for use in monitoring the gains of the photomultiplier tubes used in the VERITAS gamma-ray telescopes. This system uses blue light-emitting diodes (LEDs) so it can be operated at much higher rates than a traditional laser-based system. Calibration information can be obtained with better statistical precision with reduced loss of observing time. The LEDs are also much less expensive than a laser. The design features of the new system are presented, along with measurements made with a prototype mounted on one of the VERITAS telescopes.

  16. Global Rebalancing: US Protection versus Europe-led reflation

    E-Print Network [OSTI]

    Irvin, George; Izurieta, Alex

    2006-01-01T23:59:59.000Z

    impact of a Europe-led reflation is re-enforced by the strong income and trade linkages with middle- income and poor regions of the world (eg, Eastern Europe, Latin America and Africa)18. An EU-led reflation supposes a set of demand... switching on the required scale within an acceptable time frame. The central point is that the extra growth cannot come entirely or even chiefly from Asia (where resources are already stretched to the limit), but must come from a combination of renewed EU...

  17. LED Luminaire Lifetime: Recommendations For Testing and Reporting |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED Lighting

  18. LED Performance Specification Series: T8 Replacement Lamps

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED LightingOutdoor

  19. LED T8 Replacement Lamps | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED LightingOutdoorLEDT8

  20. LEDs Ready for Takeoff at Louisiana Airport | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED

  1. Philips Lumileds Develops a Low-Cost, High-Power, Warm-White LED Package

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, Philips Lumileds has developed a low-cost, high-power, warm-white LED package for general illumination. During the course of the two-year project, this package was used to commercialize a series of products with correlated color temperatures (CCTs) ranging from 2700 to 5700 K, under the product name LUXEON M. A record efficacy of nearly 125 lm/W was demonstrated at a flux of 1023 lumens, a CCT of 3435 K, and a color rendering index (CRI) of more than 80 at room temperature in the productized package. In an R&D package, a record efficacy of more than 133 lm/W at a flux of 1015 lumens, a CCT of 3475 K, and a CRI greater than 80 at room temperature were demonstrated.

  2. Measured turbulent mixing in a small-scale circuit breaker model

    E-Print Network [OSTI]

    Basse, Nils Plesner

    to understand how hot gas from the arc zone mixes with colder gas in the mixing volume. This mixing process with cold gas that is present, for example, in the exhausts and mixing volume. Understanding the details of the mixing process is imperative to estimate the temperature distribution within the entire breaker volume

  3. The Elusive “Life” of LEDs: How TM-21 Contributes to the Solution

    SciTech Connect (OSTI)

    Richman, Eric E.

    2011-11-18T23:59:59.000Z

    This magazine article discusses the issue of LED 'lifetime' and explains where TM-21 plays as part of the solution to this issue. In August 2011, the Illuminating Engineering Society (IES) published the TM-21 document entitled 'Lumen degradation lifetime estimation method for LED light sources.' TM-21 is the IES-recommended method for projecting lumen degradation of an LED package, array or module based on data collected according to LM-80. The lighting community expects TM-21 to become the standard method for projecting useful LED lighting product life at realistic operating temperature. This article presents the development process behind TM-21, and clarifies how and when to apply the lifetime extrapolation method to arrive at reasonable and useful estimations. Why TM-21 and why now? We are all familiar with the very real but sometimes exaggerated long-life attributes of LED technology. Not the least of these is the potential for very long life that helps make it an attractive design choice. The trick has been and continues to be how to measure or estimate this longevity to provide assurance to users of this technology's reliability (life) compared to other options. We also understand that the overall reliability of a complete LED lighting fixture can be affected by the reliability of individual product components (driver, lens, etc.) and should be accounted for in lifetime estimations. The useful life of standard lighting technologies is defined as the time to filament or cathode failure. For most of these lamps, the time period prior to failure exhibits acceptable levels of light output, as shown with the solid lines in Fig. 1. This makes it easy to determine when to replace the lamp. However, LEDs do not have filament burn-out that conveniently announces the end of life (dashed line in Fig. 1). Further, the rapid development of the technology and the desire to bring products to market in a timely manner does not allow for actual testing verification of the long lives claimed (100,000 or even 35,000 hours). As a result, the industry has come to accept a definition of the end of the useful life of an LED as the point when it no longer provides a specified level of light output. And finally, the life and performance of LED lighting products depends greatly on excess heat retained at the diode. This is why LEDs require testing at multiple temperatures such that when a source is installed in a luminaire, its actual operating temperature can be measured and lumen depreciation of the product can be derived. Therefore, to serve the solid-state lighting industry, the Technical Procedures Committee (TPC) of the IES proceeded to develop appropriate tests for use in rating LED product longevity. The initial need was a measure of the basic lumen degradation of LED source components identified by a module, package, or array of diodes and this came in the form of LM-80. Importantly, LM-80 only specifies how to measure lumen depreciation to a minimum of 6000 hours (but recommends testing to 10,000 hours or longer). LM-80 stops short of using that data to estimate any depreciation after that, which is where TM-21 comes in. The TM-21 working group (WG) as part of the IES TPC was formed to develop the lumen depreciation projection method and spent over three years exploring many options. The WG evaluated various projection options starting with an analysis of various mathematical, engineering-based models to provide effective depreciation fit and a useful projection method. Next, the WG analyzed LED lumen maintenance behavior using over 40 sets of LM-80-08 test data (20 sets with 10,000 hours or more) collected from four major LED manufacturers. The working group also examined the accuracy of proposed projections using various proposed models and LM-80 data that extended up to 15,000 hours.

  4. An Brief Overview Of Using LEDs In Lab

    E-Print Network [OSTI]

    Baas, Bevan

    Diodes · A Light-Emitting Diode (LED) is a special type of diode that emits photons (light) when current ­ Forward biased Diode Operation 0 V 5 V Current ~0 high (too high)5 V 0 V I anode cathode #12;3 Light-Emitting

  5. Small Area Array-Based LED Luminaire Design

    SciTech Connect (OSTI)

    Thomas Yuan

    2008-01-09T23:59:59.000Z

    This report contains a summary of technical achievements during a three-year project to demonstrate high efficiency LED luminaire designs based on small area array-based gallium nitride diodes. Novel GaN-based LED array designs are described, specifically addressing the thermal, optical, electrical and mechanical requirements for the incorporation of such arrays into viable solid-state LED luminaires. This work resulted in the demonstration of an integrated luminaire prototype of 1000 lumens cool white light output with reflector shaped beams and efficacy of 89.4 lm/W at CCT of 6000oK and CRI of 73; and performance of 903 lumens warm white light output with reflector shaped beams and efficacy of 63.0 lm/W at CCT of 2800oK and CRI of 82. In addition, up to 1275 lumens cool white light output at 114.2 lm/W and 1156 lumens warm white light output at 76.5 lm/W were achieved if the reflector was not used. The success to integrate small area array-based LED designs and address thermal, optical, electrical and mechanical requirements was clearly achieved in these luminaire prototypes with outstanding performance and high efficiency.

  6. Ultratech Develops an Improved Lithography Tool for LED Wafer Manufacturing

    Broader source: Energy.gov [DOE]

    Ultratech modified an existing lithography tool used for semiconductor manufacturing to better meet the cost and performance targets of the high-brightness LED manufacturing industry. The goal was to make the equipment compatible with the wide range of substrate diameters and thicknesses prevalent in the industry while reducing the capital cost and the overall cost of ownership (COO).

  7. Development and Evaluation of an Advanced LED Warning System for

    E-Print Network [OSTI]

    Minnesota, University of

    .dot.state.mn.us/stateaid/sa_traffic_safety.html #12;Project Need · ITS Safety Plan: ITS Critical Strategy 5: Use Intersection Collision Warning.g. radar) · Utilize alternative energy source (solar and/or wind) · Utilize LED blinker signs #12;Before;Stop Case 2: #12;Roll-through Case: #12;Acknowledgments and Special Thanks · Local Road Research Board

  8. Biofuels in the ASEAN Low Emission Development Strategies (LEDS) Forum

    E-Print Network [OSTI]

    9/20/2012 1 Biofuels in the ASEAN Low Emission Development Strategies (LEDS) Forum Bangkok, Thailand 19-21 September 2012 Biofuel Policy Group Asian Institute of Technology Outline of the Presentation 1. Objectives of this Presentation 2. Background 3. Status of Biofuel Development in ASEAN 4

  9. Heterostructures for Increased Quantum Efficiency in Nitride LEDs

    SciTech Connect (OSTI)

    Davis, Robert

    2010-09-30T23:59:59.000Z

    Task 1. Development of an advanced LED simulator useful for the design of efficient nitride-based devices. Simulator will contain graphical interface software that can be used to specify the device structure, the material parameters, the operating conditions and the desired output results. I-4 Task 2. Theoretical and experimental investigations regarding the influence on the microstructure, defect concentration, mechanical stress and strain and IQE of controlled changes in the chemistry and process route of deposition of the buffer layer underlying the active region of nitride-based blue- and greenemitting LEDs. I-9 Task 3. Theoretical and experimental investigations regarding the influence on the physical properties including polarization and IQE of controlled changes in the geometry, chemistry, defect density, and microstructure of components in the active region of nitride-based blue- and green-emitting LEDs. II-37 Task 4. Theoretical and experimental investigations regarding the influence on IQE of novel heterostructure designs to funnel carriers into the active region for enhanced recombination efficiency and elimination of diffusion beyond this region. II-52 Task 5. Theoretical and experimental investigations regarding the influence of enhanced p-type doping on the chemical, electrical, and microstructural characteristics of the acceptor-doped layers, the hole injection levels at Ohmic contacts, the specific contact resistivity and the IQE of nitride-based blue- and green-emitting LEDs. Development and optical and electrical characterization of reflective Ohmic contacts to n- and p-type GaN films. I

  10. Development of Advanced LED Phosphors by Spray-based Processes for Solid State Lighting

    SciTech Connect (OSTI)

    Cabot Corporation

    2007-09-30T23:59:59.000Z

    The overarching goal of the project was to develop luminescent materials using aerosol processes for making improved LED devices for solid state lighting. In essence this means improving white light emitting phosphor based LEDs by improvement of the phosphor and phosphor layer. The structure of these types of light sources, displayed in Figure 1, comprises of a blue or UV LED under a phosphor layer that converts the blue or UV light to a broad visible (white) light. Traditionally, this is done with a blue emitting diode combined with a blue absorbing, broadly yellow emitting phosphor such as Y{sub 3}Al{sub 5}O{sub 12}:Ce (YAG). A similar result may be achieved by combining a UV emitting diode and at least three different UV absorbing phosphors: red, green, and blue emitting. These emitted colors mix to make white light. The efficiency of these LEDs is based on the combined efficiency of the LED, phosphor, and the interaction between the two. The Cabot SSL project attempted to improve the over all efficiency of the LED light source be improving the efficiency of the phosphor and the interaction between the LED light and the phosphor. Cabot's spray based process for producing phosphor powders is able to improve the brightness of the powder itself by increasing the activator (the species that emits the light) concentration without adverse quenching effects compared to conventional synthesis. This will allow less phosphor powder to be used, and will decrease the cost of the light source; thus lowering the barrier of entry to the lighting market. Cabot's process also allows for chemical flexibility of the phosphor particles, which may result in tunable emission spectra and so light sources with improved color rendering. Another benefit of Cabot's process is the resulting spherical morphology of the particles. Less light scattering results when spherical particles are used in the phosphor layer (Figure 1) compared to when conventional, irregular shaped phosphor particles are used. This spherical morphology will result in better light extraction and so an improvement of efficiency in the overall device. Cabot is a 2.5 billion dollar company that makes specialized materials using propriety spray based technologies. It is a core competency of Cabot's to exploit the spray based technology and resulting material/morphology advantages. Once a business opportunity is clearly identified, Cabot is positioned to increase the scale of the production to meet opportunity's need. Cabot has demonstrated the capability to make spherical morphology micron-sized phosphor powders by spray based routes for PDP and CRT applications, but the value proposition is still unproven for LED applications. Cabot believes that the improvements in phosphor powders yielded by their process will result in a commercial advantage over existing technologies. Through the SSL project, Cabot has produced a number of different compositions in a spherical morphology that may be useful for solid state lights, as well as demonstrated processes that are able to produce particles from 10 nanometers to 3 micrometers. Towards the end of the project we demonstrated that our process produces YAG:Ce powder that has both higher internal quantum efficiency (0.6 compared to 0.45) and external quantum efficiency (0.85 compared to 0.6) than the commercial standard (see section 3.4.4.3). We, however, only produced these highly bright materials in research and development quantities, and were never able to produce high quantum efficiency materials in a reproducible manner at a commercial scale.

  11. Abbreviated epitaxial growth mode (AGM) method for reducing cost and improving quality of LEDs and lasers

    SciTech Connect (OSTI)

    Tansu, Nelson; Chan, Helen M; Vinci, Richard P; Ee, Yik-Khoon; Biser, Jeffrey

    2013-09-24T23:59:59.000Z

    The use of an abbreviated GaN growth mode on nano-patterned AGOG sapphire substrates, which utilizes a process of using 15 nm low temperature GaN buffer and bypassing etch-back and recovery processes during epitaxy, enables the growth of high-quality GaN template on nano-patterned AGOG sapphire. The GaN template grown on nano-patterned AGOG sapphire by employing abbreviated growth mode has two orders of magnitude lower threading dislocation density than that of conventional GaN template grown on planar sapphire. The use of abbreviated growth mode also leads to significant reduction in cost of the epitaxy. The growths and characteristics of InGaN quantum wells (QWs) light emitting diodes (LEDs) on both templates were compared. The InGaN QWs LEDs grown on the nano-patterned AGOG sapphire demonstrated at least a 24% enhancement of output power enhancement over that of LEDs grown on conventional GaN templates.

  12. A Touch Panel using Silicone Rubber with embedded IR-LEDs Yuichiro Sakamoto,

    E-Print Network [OSTI]

    Tanaka, Jiro

    LED LED FTIR FTIR FTIR FTIR FTIR LED LED A Touch Panel using Silicone Rubber with embedded Shizuki and Jiro Tanaka In this paper, we present a novel touch panel using silicone rubber with embedded are difficult to detect for one made of acryl panel Moreover, it integrates IR-LEDs silicone rubber for multi

  13. New GATEWAY Report Monitors LED System Performance in a High-Temperature

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy China 2015of 2005 attheMohammed Khan -DepartmentDepartment ofDevelopment | Department

  14. New GATEWAY Report Monitors LED System Performance in a High-Temperature

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking ofOilNEW HAMPSHIREof Energy InvestigatesEnvironment | Department of

  15. Thermal Decomposition of Bulk K-CoMoSx Mixed Alcohol Catalyst Precursors and Effects on Catalyst Morphology and Performance

    SciTech Connect (OSTI)

    Menart, M. J.; Hensley, J. E.; Costelow, K. E.

    2012-09-26T23:59:59.000Z

    Cobalt molybdenum sulfide-type mixed alcohol catalysts were synthesized via calcination of precipitated bulk sulfides and studied with temperature programmed decomposition analysis. Precursors containing aqueous potassium were also considered. Precipitates thermally decomposed in unique events which released ammonia, carbon dioxide, and sulfur. Higher temperature treatments led to more crystalline and less active catalysts in general with ethanol productivity falling from 203 to 97 g (kg cat){sup -1} h{sup -1} when the calcination temperature was increased from 375 to 500 C. The addition of potassium to the precursor led to materials with crystalline potassium sulfides and good catalytic performance. In general, less potassium was required to promote alcohol selectivity when added before calcination. At calcination temperatures above 350 C, segregated cobalt sulfides were observed, suggesting that thermally decomposed sulfide precursors may contain a mixture of molybdenum and cobalt sulfides instead of a dispersed CoMoS type of material. When dimethyl disulfide was fed to the precursor during calcination, crystalline cobalt sulfides were not detected, suggesting an important role of free sulfur during decomposition.

  16. LED Retrofit Project in TSH Basement On July 14 2014, McMaster Facilities Services completed an energy conservation lighting

    E-Print Network [OSTI]

    Haykin, Simon

    replaced with the new LED (light emitting diode) tubes. LEDs have better lighting quality, lower energy

  17. OSRAM SYLVANIA Develops High-Efficiency LED Troffer Replacement

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, OSRAM SYLVANIA is developing a high-efficiency LED 2'x2' troffer replacement that is expected to be commercially available in the spring of 2012 and to be cost-competitive with existing troffers of that size. It is projected to have a light output of up to 4,000 lumens, an efficacy of more than 100 lm/W, and a CCT of 3500K.

  18. KLA-Tencor's Inspection Tool Reduces LED Manufacturing Costs

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, KLA-Tencor is developing an improved inspection tool for LED manufacturing that promises to significantly increase overall process yields and minimize expensive waste. The power of the inspection tool lies in optical detection techniques coupled with defect source analysis software to statistically correlate front-end geometric anomalies in the substrate to killer defects on the back end of the manufacturing line, which give rise to an undesirable or unusable end product.

  19. Observed Minimum Illuminance Threshold for Night Market Vendors in Kenya who use LED Lamps

    E-Print Network [OSTI]

    Johnstone, Peter

    2009-01-01T23:59:59.000Z

    data logger equipped rechargeable LED lamps, monitoring theadoption of the LED lamps, and a follow-up survey.s kiosk illuminated by an LED lamp Radecsky, K. , P.

  20. Assessing the Performance of 5mm White LED Light Sources for Developing-Country Applications

    E-Print Network [OSTI]

    Mills, Evan

    2007-01-01T23:59:59.000Z

    lamp calibrated by Labsphere Spectral measurements - LEDs inLEDs we tested is exceptionally good (as good or better than many compact fluorescent lamps),lamp. Off-grid lighting products using the poorer LEDs would

  1. Application Summary Report 22: LED MR16 Lamps

    SciTech Connect (OSTI)

    Royer, Michael P.

    2014-07-23T23:59:59.000Z

    This report analyzes the independently tested photometric performance of 27 LED MR16 lamps. It describes initial performance based on light output, efficacy, distribution, color quality, electrical characteristics, and form factor, with comparisons to a selection of benchmark halogen MR16s and ENERGY STAR qualification thresholds. Three types of products were targeted. First, CALiPER sought 3000 K lamps with the highest rated lumen output (i.e., at least 500 lm) or a claim of equivalency to a 50 W halogen MR16 or higher. The test results indicate that while the initial performance of LED MR16s has improved across the board, market-available products still do not produce the lumen output and center beam intensity of typical 50 W halogen MR16 lamps. In fact, most of the 18 lamps in this category had lower lumen output and center beam intensity than a typical 35 W halogen MR16 lamp. Second, CALiPER sought lamps with a CRI of 90 or greater. Only four manufacturers were identified with a product in this category. CALiPER testing confirmed the performance of these lamps, which are a good option for applications where high color fidelity is needed. A vast majority of the LED MR16 lamps have a CRI in the low 80s; this is generally acceptable for ambient lighting, but may not always be acceptable for focal lighting. For typical LED packages, there is a fundamental tradeoff between CRI and efficacy, but the lamps in the high-CRI group in this report still offer comparable performance to the rest of the Series 22 products in other performance areas. Finally, CALiPER sought lamps with a narrow distribution, denoted as a beam angle less than 15°. Five such lamps were purchased. Notably, no lamp was identified as having high lumen output (500 lumens or greater), high CRI (90 or greater), a narrow distribution (15° or less), and an efficacy greater than 60 lm/W. This would be an important achievement for LED MR16s especially if output could reach approximately 700 800 lumens, or the approximate equivalent of a 50 W halogen MR16 lamp. Many factors beyond photometric performance should be considered during specification. For example, performance over time, transformer and dimmer compatibility, and total system performance are all critical to a successful installation. Subsequent CALiPER reports will investigate more complex issues.

  2. LED Site Lighting in the Commercial Building Sector: Opportunities, Challenges, and the CBEA Performance Specification

    Broader source: Energy.gov [DOE]

    This March 26, 2009 webcast presented information about the Commercial Building Energy Alliances' (CBEA) efforts to explore the viability of LED site lighting in commercial parking lots. LED...

  3. High Efficacy Green LEDs by Polarization Controlled MOVPE

    SciTech Connect (OSTI)

    Wetzel, Christian

    2013-03-31T23:59:59.000Z

    Amazing performance in GaInN/GaN based LEDs has become possible by advanced epitaxial growth on a wide variety of substrates over the last decade. An immediate push towards product development and worldwide competition for market share have effectively reduced production cost and generated substantial primary energy savings on a worldwide scale. At all times of the development, this economic pressure forced very fundamental decisions that would shape huge industrial investment. One of those major aspects is the choice of epitaxial growth substrate. The natural questions are to what extend a decision for a certain substrate will limit the ultimate performance and to what extent, the choice of a currently more expensive substrate such as native GaN could overcome any of the remaining performance limitations. Therefore, this project has set out to explore what performance characteristic could be achieved under the utilization of bulk GaN substrate. Our work was guided by the hypotheses that line defects such as threading dislocations in the active region should be avoided and the huge piezoelectric polarization needs to be attenuated – if not turned off – for higher performing LEDs, particularly in the longer wavelength green and deep green portions of the visible spectrum. At their relatively lower performance level, deep green LEDs are a stronger indicator of relative performance improvements and seem particular sensitive to the challenges at hand. The project therefore made use of recently developed non-polar and semipolar bulk GaN substrates that were made available at Kyma Technologies by crystallographic cuts from thick polar growth of GaN. This approach naturally leads to rather small pieces of substrates, cm along the long side while mm along the short one. Small size and limited volume of sample material therefore set the limits of the ensuing development work. During the course of the project we achieved green and deep green LEDs in all those crystal growth orientations: polar c-plane, non- polar a-plane, non-polar m-plane, and semipolar planes. The active region in those structures shows dramatically reduced densities of threading dislocations unless the wavelength was extended as far as 510 nm and beyond. With the appearance of such defects, the light output power dropped precipitously supporting the necessity to avoid any and all of such defects to reach the active region. Further aspects of the non-polar growth orientation proved extremely promising for the development of such structures. Chief among them is our success to achieve extremely uniform quantum wells in these various crystal orientations that prove devoid of any alloy fluctuation beyond the theoretical limit of a binominal distribution. This became very Rensselaer Wetzel DE?EE0000627 3 directly apparent in highly advanced atom probe tomography performed in collaboration at Northwestern University. Furthermore, under reduced or absence of piezoelectric polarization, green emitters in those growth geometries exhibit an unsurpassed wavelength stability over very wide excitation and drive current ranges. Such a performance had not been possible in any polar c-plane growth and now places green LEDs in terms of wavelength stability up par with typical 450 nm blue emitters. The project also incorporated enabling opportunities in the development of micro and nano- patterned substrate technologies. Originally developped as a means to enhance generated light extraction we have demonstrated that the method of nano-patterning, in contrast to micro- patterning also results in a substantial reduction of threading dislocation generation. In green LEDs, we thereby see equal contributions of enhanced light extraction and reduced defect generation to a threefold enhancement of the green light output power. These results have opened entirely new approaches for future rapid and low cost epitaxial material development by avoidance of thick defect accommodation layers. All methods developed within this project have meanwhile widely been publicized by the members o

  4. Feedback-Controlled LED Photobioreactor for Photophysiological Studies of Cyanobacteria

    SciTech Connect (OSTI)

    Melnicki, Matthew R.; Pinchuk, Grigoriy E.; Hill, Eric A.; Kucek, Leo A.; Stolyar, Sergey; Fredrickson, Jim K.; Konopka, Allan; Beliaev, Alex S.

    2013-04-09T23:59:59.000Z

    A custom photobioreactor (PBR) was designed to enable automatic light adjustments using computerized feedback control. A black anodized aluminum enclosure, constructed to surround the borosilicate reactor vessel, prevents the transmission of ambient light and serves as a mount for arrays of light-emitting diodes (LEDs). The high-output LEDs provide narrow-band light of either 630 or 680 nm for preferential excitation of the cyanobacterial light-harvesting pigments, phycobilin or chlorophyll a, respectively. Custom developed software BioLume provides automatic control of optical properties and a computer feedback loop can automatically adjust the incident irradiance as necessary to maintain a fixed transmitted light through the culture, based on user-determined set points. This feedback control serves to compensate for culture dynamics which have optical effects, (e.g., changing cell density, pigment adaptations) and thus can determine the appropriate light conditions for physiological comparisons or to cultivate light-sensitive strains, without prior analyses. The LED PBR may also be controlled as a turbidostat, using a feedback loop to continuously adjust the rate of media-dilution based on the transmitted light measurements, with a fast and precise response. This cultivation system gains further merit as a high-performance analytical device, using non-invasive tools (e.g., dissolved gas sensors, online mass spectrometry) to automate real-time measurements, thus permitting unsupervised experiments to search for optimal growth conditions, to monitor physiological responses to perturbations, as well as to quantitate photophysiological parameters using an in situ light-saturation response routine.

  5. Synthesis and luminescence properties of rare earth activated phosphors for near UV-emitting LEDs for efficacious generation of white light

    E-Print Network [OSTI]

    Han, Jinkyu

    2013-01-01T23:59:59.000Z

    high-color-rendering LED lamps using oxyfluoride andin white LED. (a) Typical LED lamp package. (b) Uniformin white LED. (a) Typical LED lamp package. (b) Uniform

  6. Considerations When Comparing LED and Conventional Lighting | Department of

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T, Inc.'sEnergyTexas1.SpaceFluor Federal Services -Energy Using LEDs »

  7. LED Holiday Lights: Festive, Safe, and Efficient! | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM to 2:05PMDOE-STD-1107-97LSEED:LDVFrequentlyLED

  8. LEDs: The Future of Lighting is Here | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LEDLEDs on Semipolar

  9. LED Lighting on the National Mall | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking ofOil & Gas » MethaneJohnsonKristina Pflanz About Us KristinaLED

  10. #AskEnergySaver: LED Lights | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of Bad CholesteroliManage#AskEnergySaver: LED Lights #AskEnergySaver:

  11. Reducing LED Costs Through Innovation | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreakingMay 2015 < prevQuick Guide:U.N.June 8,PastRadiationReducing LED Costs

  12. LED Traffic Lights Get Buy American Stamp | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy ChinaofSchaeferApril 1, 1999 InspectionVolunteersKarenThisDepartment ofLED traffic lights

  13. Mixed-mode cooling.

    E-Print Network [OSTI]

    Brager, Gail

    2006-01-01T23:59:59.000Z

    curtain walls and fluorescent lighting, led to the more common building forms we see today in North America—typically all-glass,

  14. Interaction Techniques with Virtual Humans in Mixed Environments

    E-Print Network [OSTI]

    Kallmann, Marcelo

    animation have led to the integration of Virtual Humans [9] into interactive 3D environments. With emergeInteraction Techniques with Virtual Humans in Mixed Environments Selim Balcisoy, Marcelo Kallmann use virtual humans as mediators between the real and virtual world. Keywords: Interaction Techniques

  15. Slutrapport for PSO 337-068 Udvikling af LED lyskilder og lamper

    E-Print Network [OSTI]

    bulb. - two LED pendants/lamps, a LED table lamp and a chair with LED lighting developed by designers Cluster lampe 13 Teknisk design af Cluster 15 Konklusion 16 Lysflyder 17 Hvordan opstod ideen om en LEDSlutrapport for PSO 337-068 Udvikling af LED lyskilder og lamper Carsten Dam-Hansen, Paul Michael

  16. mixed-bean-chili

    E-Print Network [OSTI]

    ... J. Infante) MIXED BEAN CHILI So, I added 1 cup of tvp to 2 cups of water, ... was about 6 cups of water to mix everything together) Cook for about 5 hours at ...

  17. Revolutionary Method for Increasing the Efficiency of White Light Quantum Dot LEDs

    SciTech Connect (OSTI)

    Duty, Chad E [ORNL; Bennett, Charlee J C [ORNL; Sabau, Adrian S [ORNL; Jellison Jr, Gerald Earle [ORNL; Boudreaux, Philip R [ORNL; Walker, Steven C [ORNL; Ott, Ronald D [ORNL

    2011-01-01T23:59:59.000Z

    Covering a light-emitting diode (LED) with quantum dots (QDs) can produce a broad spectrum of white light. However, current techniques for applying QDs to LEDs suffer from a high density of defects and a non-uniform distribution of QDs, which respec-tively diminish the efficiency and quality of emitted light. Oak Ridge National Laboratory (ORNL) has the unique capability to thermally anneal QD structures at extremely high power densities for very short durations. This process, called pulse thermal proc-essing (PTP), reduces the number of point defects while main-taining the size and shape of the original QD nanostructure. Therefore, the efficiency of the QD wavelength conversion layer is improved without altering the emission spectrum defined by the size distribution of the quantum dot nanoparticles. The cur-rent research uses a thermal model to predict annealing tempera-tures during PTP and demonstrates up to a 300% increase in pho-toluminescence for QDs on passive substrates

  18. Development of substrate-removal-free vertical ultraviolet light-emitting diode (RefV-LED)

    SciTech Connect (OSTI)

    Kurose, N., E-mail: kurose@fc.ritsumei.ac.jp; Aoyagi, Y. [The Research Organization of Science and Technology, Ritsumeikan University, 1-1-1, Noji-higashi, Kusatsu, Shiga 525-8577 (Japan)] [The Research Organization of Science and Technology, Ritsumeikan University, 1-1-1, Noji-higashi, Kusatsu, Shiga 525-8577 (Japan); Shibano, K.; Araki, T. [Department of Science and Technology, Ritsumeikan University, 1-1-1, Noji-higashi, Kusatsu, Shiga 525-8577 (Japan)] [Department of Science and Technology, Ritsumeikan University, 1-1-1, Noji-higashi, Kusatsu, Shiga 525-8577 (Japan)

    2014-02-15T23:59:59.000Z

    A vertical ultraviolet (UV) light-emitting diode (LED) that does not require substrate removal is developed. Spontaneous via holes are formed in n-AlN layer epitaxially grown on a high conductive n+Si substrate and the injected current flows directly from the p-electrode to high doped n{sup +} Si substrate through p-AlGaN, multi-quantum wells, n-AlGaN and spontaneous via holes in n-AlN. The spontaneous via holes were formed by controlling feeding-sequence of metal-organic gas sources and NH{sub 3} and growth temperature in MOCVD. The via holes make insulating n-AlN to be conductive. We measured the current-voltage, current-light intensity and emission characteristics of this device. It exhibited a built-in voltage of 3.8 V and emission was stated at 350 nm from quantum wells with successive emission centered at 400?nm. This UV LED can be produced, including formation of n and p electrodes, without any resist process.

  19. Rotational Mixing and Lithium Depletion

    E-Print Network [OSTI]

    Pinsonneault, M H

    2010-01-01T23:59:59.000Z

    I review basic observational features in Population I stars which strongly implicate rotation as a mixing agent; these include dispersion at fixed temperature in coeval populations and main sequence lithium depletion for a range of masses at a rate which decays with time. New developments related to the possible suppression of mixing at late ages, close binary mergers and their lithium signature, and an alternate origin for dispersion in young cool stars tied to radius anomalies observed in active young stars are discussed. I highlight uncertainties in models of Population II lithium depletion and dispersion related to the treatment of angular momentum loss. Finally, the origins of rotation are tied to conditions in the pre-main sequence, and there is thus some evidence that enviroment and planet formation could impact stellar rotational properties. This may be related to recent observational evidence for cluster to cluster variations in lithium depletion and a connection between the presence of planets and s...

  20. Thermal dissociation behavior and dissociation enthalpies of methane-carbon dioxide mixed hydrates

    SciTech Connect (OSTI)

    Kwon, T.H.; Kneafsey, T.J.; Rees, E.V.L.

    2011-02-15T23:59:59.000Z

    Replacement of methane with carbon dioxide in hydrate has been proposed as a strategy for geologic sequestration of carbon dioxide (CO{sub 2}) and/or production of methane (CH{sub 4}) from natural hydrate deposits. This replacement strategy requires a better understanding of the thermodynamic characteristics of binary mixtures of CH{sub 4} and CO{sub 2} hydrate (CH{sub 4}-CO{sub 2} mixed hydrates), as well as thermophysical property changes during gas exchange. This study explores the thermal dissociation behavior and dissociation enthalpies of CH{sub 4}-CO{sub 2} mixed hydrates. We prepared CH{sub 4}-CO{sub 2} mixed hydrate samples from two different, well-defined gas mixtures. During thermal dissociation of a CH{sub 4}-CO{sub 2} mixed hydrate sample, gas samples from the head space were periodically collected and analyzed using gas chromatography. The changes in CH{sub 4}-CO{sub 2} compositions in both the vapor phase and hydrate phase during dissociation were estimated based on the gas chromatography measurements. It was found that the CO{sub 2} concentration in the vapor phase became richer during dissociation because the initial hydrate composition contained relatively more CO{sub 2} than the vapor phase. The composition change in the vapor phase during hydrate dissociation affected the dissociation pressure and temperature; the richer CO{sub 2} in the vapor phase led to a lower dissociation pressure. Furthermore, the increase in CO{sub 2} concentration in the vapor phase enriched the hydrate in CO{sub 2}. The dissociation enthalpy of the CH{sub 4}-CO{sub 2} mixed hydrate was computed by fitting the Clausius-Clapeyron equation to the pressure-temperature (PT) trace of a dissociation test. It was observed that the dissociation enthalpy of the CH{sub 4}-CO{sub 2} mixed hydrate lays between the limiting values of pure CH{sub 4} hydrate and CO{sub 2} hydrate, increasing with the CO{sub 2} fraction in the hydrate phase.

  1. Vehicle Traffic Control Signal Heads— Light Emitting Diode Circular Signal Supplement (VTCSH-LED). This replaced the so-called Interim LED Purchase Specifications,

    E-Print Network [OSTI]

    S. Behura

    Engineers ’ (ITE) specification for light-emitting diode (LED) circular traffic signals recently was updated (June 27, 2005) and published under the name

  2. Mixing fraction of inner solar system material in comet 81P/Wild2

    SciTech Connect (OSTI)

    Westphal, Andrew J.; Fakra, Sirine C.; Gainsforth, Zack; Marcus, Matthew A.; Ogliore, Ryan C.; Butterworth, Anna L.

    2008-04-01T23:59:59.000Z

    The presence of crystalline silicates in the comae of comets, inferred through infrared observations, has been a long-standing puzzle. Crystalline silicates are unexpectedif comets are composed of pristine interstellar material, since interstellar silicates are almost entirely amorphous. Heating to> 1100 K can anneal silicates to crystallinity,but no protoplanetary heating sources have been identified that were sufficiently strong to heat materials in the outer nebula to such high temperatures. This conundrum led to the suggestion that large-scalemixing was important in theprotoplanetary disk. Reports of refractory calcium - aluminum-rich inclusion-like objects and large concentrations of noble gases in Stardust samples underscore the need for such mixing. However, the evidence from the Stardust samples until now has been largely anecdotal, and it has not been possible to place quantitative constraints on the mixing fraction. Here we report synchrotron-based X-ray microprobe measurements of the relative concentrations of the chemical state of iron in material from a known comet, the Jupiter-family comet 81P/Wild2. We find that the comet is rich in iron sulfides. The elemental S/Fe ratio based on the sulfide concentration, S/Fe> 0.31(2 sigma), is higher than in most chondritic meteorites. We also found that Fe-bearing silicates are at least 50percent crystalline. Based on these measurements, we estimate the fraction psi of inner nebular material in 81P/Wild2. With the lower bound on the crystalline Fe-bearing silicate fraction, we find that psi> 0.5. If the observed S depletion in the inner solar system predated or was contemporaneous with large-scale mixing, our lower bound on the S/Fe ratio gives an upper bound on psi of ~;; 0.65. This measurement may be used to test mixing models of the early solar system.

  3. Mixed-mode cooling.

    E-Print Network [OSTI]

    Brager, Gail

    2006-01-01T23:59:59.000Z

    ASHRAE’s permission. Mixed-Mode Cooling Photo Credit: Paulnatural ventilation for cooling. Buildings typically had1950s of large-scale mechanical cooling, along with other

  4. Intel Led OpenMP Training Session at NERSC This Wednesday March...

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

    Led OpenMP Training Session at NERSC This Wednesday March 25 Intel Led OpenMP Training Session at NERSC This Wednesday March 25 March 24, 2015 by Katie Antypas (0 Comments) This...

  5. Fabrication of InGaP LEDs on a graded buffer substrate

    E-Print Network [OSTI]

    Martínez, Josué F

    2007-01-01T23:59:59.000Z

    Introduction: Computer display panels create a vast color palette by combining color from three light emitting diodes (LEDs), each producing red, green, or blue light. The light from these three LEDs is chosen so that the ...

  6. Have You Used LED Lighting? Tell Us About It. | Department of...

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

    It. May 7, 2009 - 5:00am Addthis This week, John shared his experiences with light-emitting diode (LED) lighting. In a future blog, he'll share more about LED lighting. Have you...

  7. An Investigation into the Perception of Color under LED White Composite Spectra with Modulated Color Rendering

    E-Print Network [OSTI]

    O'Reilly, Una-May

    emitting diodes, LEDs. We examined seven LED white composite spectra with different color rendering of a pilot study that evaluates the perceptual impact of modulation of color rendering using multi-chip light

  8. Development and Industrialization of InGaN/GaN LEDs on Patterned...

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

    of InGaNGaN LEDs on Patterned Sapphire Substrates for Low Cost Emitter Architecture Development and Industrialization of InGaNGaN LEDs on Patterned Sapphire...

  9. Text-Alternative Version: Model Specification for LED Roadway Luminaires Webcast

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "Model Specification for LED Roadway Luminaires" webcast, held November 15, 2011.

  10. Text-Alternative Version: Successful Selection of LED Streetlight Luminaires Webcast

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "Successful Selection of LED Streetlight Luminaires" webcast, held March 6, 2013.

  11. TESLA-FEL 2007-03 Application of low cost GaAs LED as neutron

    E-Print Network [OSTI]

    neutrons in unbiased Gallium Arsenide (GaAs) Light Emitting Diodes (LED) resulted in a reduction Keywords: COTS components, Displacement damage, Electron Linear Accelerator, GaAs Light emitting diode (LED) Gallium Arsenide (GaAs) light emitting diode (LED) for the assessment of integrated neutron fluence

  12. UV-LED LITHOGRAPHY FOR 3-D HIGH ASPECT RATIO MICROSTRUCTURE PATTERNING

    E-Print Network [OSTI]

    in microfabrication. Table 1 compares the performance of UV-LEDs with a mercury lamp for several key parametersUV-LED LITHOGRAPHY FOR 3-D HIGH ASPECT RATIO MICROSTRUCTURE PATTERNING Jungkwun `JK' Kim*, Seung of Technology, Atlanta, GA, USA ABSTRACT This paper presents a UV lithography method that utilizes a UV-LED

  13. Color shift reduction of a multi-domain IPS-LCD using RGB-LED backlight

    E-Print Network [OSTI]

    Wu, Shin-Tson

    -emitting diodes (LEDs) and cold-cathode fluorescent lamp (CCFL) backlights. Simulation results indicateColor shift reduction of a multi-domain IPS- LCD using RGB-LED backlight Ruibo Lu, Qi Hong, Zhibing that the LED backlight exhibits a wider color gamut, better angular color uniformity, and 2-4X smaller static

  14. Issues, Models and Solutions for Triac Modulated Phase Dimming of LED Lamps

    E-Print Network [OSTI]

    Lehman, Brad

    Issues, Models and Solutions for Triac Modulated Phase Dimming of LED Lamps Dustin Rand (Raytheon Edison socket LED lamps directly from residential phase modulated dimmer switches. In order to explain brightness "White Light" LEDs have experts predicting that the "bright white replacement lamp" could trigger

  15. Liquid mixing device

    SciTech Connect (OSTI)

    O'Leary, R. P.

    1985-08-06T23:59:59.000Z

    A mixing device for mixing at least two liquids to produce a homogenous mixture. The device includes an elongated chamber in which a vertically oriented elongated mixing cavity is located. The cavity is sealed at its lower end and it is open at its upper end and in communication with the interior of the chamber. An elongated conduit extends the length of the cavity and is adapted to receive liquids to be mixed. The conduit includes a plurality of ports located at longitudinally spaced positions therealong and which ports are directed in different directions. The ports create plural streams of liquid which interact and mix with one another within the cavity. The mixed liquids overflow the cavity and out its top end into the chamber 24. The chamber 24 includes an outlet from which the mixed liquids are withdrawn. In accordance with the preferred embodiment gas eductor means are provided in the inlet to the conduit to introduce gas bubbles within the cavity. Gas vent means are also provided in the device to vent any introduced gases from the device so that only the mixed liquids flow out the outlet.

  16. Demonstration Assessment of Light Emitting Diode (LED) Residential Downlights and Undercabinet Lights in the Lane County Tour of Homes, Eugene, Oregon

    SciTech Connect (OSTI)

    Ton, My K.; Richman, Eric E.; Gilbride, Theresa L.

    2008-11-10T23:59:59.000Z

    In August 2008 the Pacific Northwest National Laboratory (PNNL) conducted a light emitting diode (LED) residential lighting demonstration project for the U.S. Department of Energy (DOE), Office of Building Technologies, as part of DOE’s Solid State Lighting (SSL) Technology Demonstration Gateway Program. Two lighting technologies, an LED replacement for downlight lamps (bulbs) and an LED undercabinet lighting fixture, were tested in the demonstration which was conducted in two homes built for the 2008 Tour of Homes in Eugene, Oregon. The homes were built by the Lane County Home Builders Association (HBA), and Future B Homes. The Energy Trust of Oregon (ETO) also participated in the demonstration project. The LED downlight product, the LR6, made by Cree LED Lighting Solutions acts as a screw-in replacement for incandescent and halogen bulbs in recessed can downlights. The second product tested is Phillips/Color Kinetics’ eW® Profile Powercore undercabinet fixture designed to mount under kitchen cabinets to illuminate the countertop and backsplash surfaces. Quantitative and qualitative measurements of light performance and electrical power usage were taken at each site before and after initially installed halogen and incandescent lamps were replaced with the LED products. Energy savings and simple paybacks were also calculated and builders who toured the homes were surveyed for their responses to the LED products. The LED downlight product drew 12 Watts of power, cutting energy use by 82% compared to the 65W incandescent lamp and by 84% compared to the 75W halogen lamp. The LED undercabinet fixture drew 10 watts, cutting energy use by 83% to 90% compared to the halogen product, which was tested at two power settings: a low power 60W setting and a high power 105W setting. The LED downlight consistently provided more light than the halogen and incandescent lamps in horizontal measurements at counter height and floor level. It also outperformed in vertical illuminance measurements taken on the walls, indicating better lateral dispersion of the light. The undercabinet fixture’s light output was midway between the low and high power halogen undercabinet fixture light outputs (35.8 foot candle versus 13.4 fc and 53.4 fc) but it produced a more uniform light (max/min ratio of 7.0 versus 10.8). The color correlated temperature (CCT, the blue or yellowness) of the LED light correlated well with the halogen and incandescent lights (2675 K vs 2700 K). The color rendering of the LED downlight also correlated well at 92 CRI compared to 100 CRI for the halogen and incandescent lamps. The LED undercabinet fixture had measures of 2880 K CCT and 71 CRI compared to the 2700 K and 100 CRI scores for the halogen undercabinet fixture. Builders who toured the homes were surveyed; they gave the LED downlight high marks for brightness, said the undercabinet improved shadows and glare and said both products improved overall visibility, home appearance, and home value. Paybacks on the LED downlight ranged from 7.6 years (assuming electricity cost of 11 c/kWh) to 13.5 years (at 5C/kWh). Paybacks on the LED undercabinet fixture in a new home ranged from 4.4 years (11c/kWh electricity) to 7.6 years (5c/kWh) based on product costs of $95 per LED downlight and $140 per LED undercabinet fixture at 3 hrs per day of usage for the downlight and 2 hrs per day for the undercabinet lighting.

  17. Guidelines for mixed waste minimization

    SciTech Connect (OSTI)

    Owens, C.

    1992-02-01T23:59:59.000Z

    Currently, there is no commercial mixed waste disposal available in the United States. Storage and treatment for commercial mixed waste is limited. Host States and compacts region officials are encouraging their mixed waste generators to minimize their mixed wastes because of management limitations. This document provides a guide to mixed waste minimization.

  18. Performance of T12 and T8 Fluorescent Lamps and Troffers and LED Linear Replacement Lamps CALiPER Benchmark Report

    SciTech Connect (OSTI)

    Myer, Michael; Paget, Maria L.; Lingard, Robert D.

    2009-01-16T23:59:59.000Z

    The Department of Energy (DOE) Commercially Available LED Product Evaluation and Reporting (CALiPER) Program was established in 2006 to investigate the performance of light-emitting diode (LED) based luminaires and replacement lamps. To help users better compare LED products with conventional lighting technologies, CALiPER has also performed benchmark research and testing of traditional (i.e., non-LED) lamps and fixtures. This benchmark report addresses standard 4-foot fluorescent lamps (i.e., T12 and T8) and the 2-foot by 4-foot recessed troffers in which they are commonly used. This report also examines available LED replacements for T12 and T8 fluorescent lamps, and their application in fluorescent troffers. The construction and operation of linear fluorescent lamps and troffers are discussed, as well as fluorescent lamp and fixture performance, based on manufacturer data and CALiPER benchmark testing. In addition, the report describes LED replacements for linear fluorescent lamps, and compares their bare lamp and in situ performance with fluorescent benchmarks on a range of standard lighting measures, including power usage, light output and distribution, efficacy, correlated color temperature, and the color rendering index. Potential performance and application issues indicated by CALiPER testing results are also examined.

  19. ADVANCED MIXING MODELS

    SciTech Connect (OSTI)

    Lee, S.; Dimenna, R.; Tamburello, D.

    2011-02-14T23:59:59.000Z

    The process of recovering and processing High Level Waste (HLW) the waste in storage tanks at the Savannah River Site (SRS) typically requires mixing the contents of the tank with one to four mixers (pumps) located within the tank. The typical criteria to establish a mixed condition in a tank are based on the number of pumps in operation and the time duration of operation. To ensure that a mixed condition is achieved, operating times are typically set conservatively long. This approach results in high operational costs because of the long mixing times and high maintenance and repair costs for the same reason. A significant reduction in both of these costs might be realized by reducing the required mixing time based on calculating a reliable indicator of mixing with a suitably validated computer code. The focus of the present work is to establish mixing criteria applicable to miscible fluids, with an ultimate goal of addressing waste processing in HLW tanks at SRS and quantifying the mixing time required to suspend sludge particles with the submersible jet pump. A single-phase computational fluid dynamics (CFD) approach was taken for the analysis of jet flow patterns with an emphasis on the velocity decay and the turbulent flow evolution for the farfield region from the pump. Literature results for a turbulent jet flow are reviewed, since the decay of the axial jet velocity and the evolution of the jet flow patterns are important phenomena affecting sludge suspension and mixing operations. The work described in this report suggests a basis for further development of the theory leading to the identified mixing indicators, with benchmark analyses demonstrating their consistency with widely accepted correlations. Although the indicators are somewhat generic in nature, they are applied to Savannah River Site (SRS) waste tanks to provide a better, physically based estimate of the required mixing time. Waste storage tanks at SRS contain settled sludge which varies in height from zero to 10 ft. The sludge has been characterized and modeled as micron-sized solids, typically 1 to 5 microns, at weight fractions as high as 20 to 30 wt%, specific gravities to 1.4, and viscosities up to 64 cp during motion. The sludge is suspended and mixed through the use of submersible slurry jet pumps. To suspend settled sludge, water is added to the tank as a slurry medium and stirred with the jet pump. Although there is considerable technical literature on mixing and solid suspension in agitated tanks, very little literature has been published on jet mixing in a large-scale tank. One of the main objectives in the waste processing is to provide feed of a uniform slurry composition at a certain weight percentage (e.g. typically {approx}13 wt% at SRS) over an extended period of time. In preparation of the sludge for slurrying, several important questions have been raised with regard to sludge suspension and mixing of the solid suspension in the bulk of the tank: (1) How much time is required to prepare a slurry with a uniform solid composition? (2) How long will it take to suspend and mix the sludge for uniform composition in any particular waste tank? (3) What are good mixing indicators to answer the questions concerning sludge mixing stated above in a general fashion applicable to any waste tank/slurry pump geometry and fluid/sludge combination?

  20. A multifluid mix model with material strength effects

    SciTech Connect (OSTI)

    Chang, C. H. [Los Alamos National Laboratory; Scannapieco, A. J. [Los Alamos National Laboratory

    2012-04-23T23:59:59.000Z

    We present a new multifluid mix model. Its features include material strength effects and pressure and temperature nonequilibrium between mixing materials. It is applicable to both interpenetration and demixing of immiscible fluids and diffusion of miscible fluids. The presented model exhibits the appropriate smooth transition in mathematical form as the mixture evolves from multiphase to molecular mixing, extending its applicability to the intermediate stages in which both types of mixing are present. Virtual mass force and momentum exchange have been generalized for heterogeneous multimaterial mixtures. The compression work has been extended so that the resulting species energy equations are consistent with the pressure force and material strength.

  1. DUAL USE OF LEDS: SIGNALING AND COMMUNICATIONS IN ITS Grantham Pang, Chi-ho Chan, Hugh Liu, Thomas Kwan

    E-Print Network [OSTI]

    Pang, Grantham

    of an incandescent lamp is 800 hours while the life expectancy of LED is 10-23 years. This result shows that LED has : · LED indicator lamps (as in some dashboard, traffic signals, card readers). · LED displays (1 DUAL USE OF LEDS: SIGNALING AND COMMUNICATIONS IN ITS Grantham Pang, Chi-ho Chan, Hugh Liu

  2. Fuel Mix Disclosure

    Broader source: Energy.gov [DOE]

    Hawaii requires the state’s retail electric suppliers to disclose details regarding the fuel mix of their electric generation to retail customers. Such information must be provided on customers’...

  3. Fuel Mix Disclosure

    Broader source: Energy.gov [DOE]

    Washington’s retail electric suppliers must disclose details regarding the fuel mix of their electric generation to customers. Electric suppliers must provide such information in a standard format...

  4. Correlating electroluminescence characterization and physics-based models of InGaN/GaN LEDs: Pitfalls and open issues

    SciTech Connect (OSTI)

    Calciati, Marco; Vallone, Marco; Zhou, Xiangyu; Ghione, Giovanni [Dipartimento di Elettronica e Telecomunicazioni, Politecnico di Torino, corso Duca degli Abruzzi 24, 10129 Torino (Italy); Goano, Michele, E-mail: michele.goano@polito.it; Bertazzi, Francesco [Dipartimento di Elettronica e Telecomunicazioni, Politecnico di Torino, corso Duca degli Abruzzi 24, 10129 Torino (Italy); IEIIT-CNR, Politecnico di Torino, corso Duca degli Abruzzi 24, 10129 Torino (Italy); Meneghini, Matteo; Meneghesso, Gaudenzio; Zanoni, Enrico [Dipartimento di Ingegneria dell'Informazione, Universitŕ di Padova, Via Gradenigo 6/B, 35131 Padova (Italy); Bellotti, Enrico [Department of Electrical and Computer Engineering, Boston University, 8 Saint Mary's Street, 02215 Boston, MA (United States); Verzellesi, Giovanni [Dipartimento di Scienze e Metodi dell'Ingegneria, Universitŕ di Modena e Reggio Emilia, 42122 Reggio Emilia (Italy); Zhu, Dandan; Humphreys, Colin [Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS (United Kingdom)

    2014-06-15T23:59:59.000Z

    Electroluminescence (EL) characterization of InGaN/GaN light-emitting diodes (LEDs), coupled with numerical device models of different sophistication, is routinely adopted not only to establish correlations between device efficiency and structural features, but also to make inferences about the loss mechanisms responsible for LED efficiency droop at high driving currents. The limits of this investigative approach are discussed here in a case study based on a comprehensive set of current- and temperature-dependent EL data from blue LEDs with low and high densities of threading dislocations (TDs). First, the effects limiting the applicability of simpler (closed-form and/or one-dimensional) classes of models are addressed, like lateral current crowding, vertical carrier distribution nonuniformity, and interband transition broadening. Then, the major sources of uncertainty affecting state-of-the-art numerical device simulation are reviewed and discussed, including (i) the approximations in the transport description through the multi-quantum-well active region, (ii) the alternative valence band parametrizations proposed to calculate the spontaneous emission rate, (iii) the difficulties in defining the Auger coefficients due to inadequacies in the microscopic quantum well description and the possible presence of extra, non-Auger high-current-density recombination mechanisms and/or Auger-induced leakage. In the case of the present LED structures, the application of three-dimensional numerical-simulation-based analysis to the EL data leads to an explanation of efficiency droop in terms of TD-related and Auger-like nonradiative losses, with a C coefficient in the 10{sup ?30} cm{sup 6}/s range at room temperature, close to the larger theoretical calculations reported so far. However, a study of the combined effects of structural and model uncertainties suggests that the C values thus determined could be overestimated by about an order of magnitude. This preliminary attempt at uncertainty quantification confirms, beyond the present case, the need for an improved description of carrier transport and microscopic radiative and nonradiative recombination mechanisms in device-level LED numerical models.

  5. Measured Off-Grid LED Lighting System Performance

    SciTech Connect (OSTI)

    Granderson, Jessica; Galvin, James; Bolotov, Dmitriy; Clear, Robert; Jacobson, Arne; Mills, Evan

    2008-12-18T23:59:59.000Z

    This report is a product of our ongoing effort to support the development of high-quality yet affordable products for off-grid lighting in the developing world that have good potential to succeed in the market. The effort includes work to develop low-cost testing procedures, to identify useful performance metrics, and to facilitate the development of industry standards and product rating protocols. We conducted laboratory testing of nine distinct product lines. In some cases we also tested multiple generations of a single product line and/or operating modes for a product. The resultsare summarized in Table 1. We found that power consumption and light output varied by nearly a factor of 12, with efficacy varying by a factor of more than six. Of particular note, overall luminous efficacy varied from 8.2 to 53.1 lumens per watt. Color quality indices variedmaterially, especially for correlated color temperature. Maximum illuminance, beamcandlepower, and luminance varied by 8x, 32x, and 61x respectively, suggesting considerable differences among products in terms of service levels and visual comfort. Glare varied by1.4x, and was above acceptable thresholds in most cases. Optical losses play a role in overall performance, varying by a factor of 3.2 and ranging as high as 24percent. These findings collectively indicate considerable potential for improved product design.

  6. Loop Current Mixed Layer Energy Response to Hurricane Lili (2002). Part I: Observations

    E-Print Network [OSTI]

    Miami, University of

    Loop Current Mixed Layer Energy Response to Hurricane Lili (2002). Part I: Observations ERIC W-dimensional oceanic energy evolution in response to Hurricane Lili's (2002) passage. Mixed layer temperature analyses, Florida (Manuscript received 4 May 2011, in final form 3 October 2011) ABSTRACT The ocean mixed layer

  7. 13. Neutrino mixing 1 13. NEUTRINO MASS, MIXING, AND OSCILLATIONS

    E-Print Network [OSTI]

    13. Neutrino mixing 1 13. NEUTRINO MASS, MIXING, AND OSCILLATIONS Updated October 2011 by K compelling evidences for oscillations of neutrinos caused by nonzero neutrino masses and neutrino mixing. The data imply the existence of 3-neutrino mixing in vacuum. We review the theory of neutrino oscillations

  8. 13. Neutrino mixing 1 13. NEUTRINO MASS, MIXING, AND OSCILLATIONS

    E-Print Network [OSTI]

    13. Neutrino mixing 1 13. NEUTRINO MASS, MIXING, AND OSCILLATIONS Written May 2010 by K. Nakamura for oscillations of neutrinos caused by nonzero neutrino masses and neutrino mixing. The data imply the existence of 3-neutrino mixing in vacuum. We review the theory of neutrino oscillations, the phenomenology

  9. LED exit signs: Improved technology leads the way to energy savings

    SciTech Connect (OSTI)

    Sardinsky, R.; Hawthorne, S.

    1994-12-31T23:59:59.000Z

    Recent innovations in light-emitting diode (LED) exit signs may make LED signs the best choice among the energy efficient options available. In the past, LED signs have offered low power consumption, projected long lamp life, and low maintenance requirements. Now, the best of the LED signs also offer improved optical designs that reduce their already low power consumption while improving visibility and appearance, and even reduce their cost. LED exit signs are gaining market share, and E Source expects this technology to eventually dominate over incandescent, compact fluorescent, and electroluminescent signs. More research is needed, however, to confirm manufacturers` claims of 20-year operating lives for LED signs. Conservative estimates place the number of exit signs in US buildings at about 40 million. Although each sign represents a very small part of a building`s load, exit signs are ready targets for energy efficiency upgrades -- they operate continuously and most use inefficient incandescent sources. With an LED sign, annual energy and maintenance costs can be reduced by more than 90 percent compared to a typical incandescent sign. Low annual costs help to offset the LED sign`s relatively high first cost. More than 25 utilities offer DSM incentives for energy efficient exit signs, and efficient alternatives are becoming more readily available. Recent improvements in optical designs enable many LED signs to visually out perform other sources. In addition to these benefits, LED exit signs have lower life cycle cost than most other options. The biggest barrier to their success, however, is that their first cost has been considerably higher than competing technologies. LED sign prices are falling rapidly, though, because manufacturers are continually improving optical designs of the fixtures to use fewer LEDs and thus even less energy while providing better performance.

  10. Philips Lumileds Achieves 139 lm/W in a Neutral White LED

    Broader source: Energy.gov [DOE]

    Philips Lumileds' LUXEON Rebel LED can now deliver 139 lm/W in a neutral white LED. The top bin LED, developed with a single InGaN die and phosphor conversion, shows high-performance characteristics up to 139 lm/W and 138 lumens at 350 mA, with a forward voltage of 2.83 V. The CCT of the device is 5385K and the CRI is 70.

  11. Effect of ocean temperature on southwestern U.S. climate analyzed

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

    LANL's Space and Remote Sensing group led the scientists to perform multiple linear regression analysis of surface air temperature and precipitation records provided by the...

  12. Mixed surfactant systems for enhanced oil recovery

    SciTech Connect (OSTI)

    Llave, F.M.; Gall, B.L.; Noll, L.A.

    1990-12-01T23:59:59.000Z

    The results of an evaluation of mixed surfactant systems for enhanced oil recovery are described. Several surfactant combinations have been studied. These include alkyl aryl sulfonates as primary surfactants and carboxymethylated ethoxylated (CME) surfactants and ethoxylated sulfonates (ES) as secondary surfactants. The ethoxylated surfactants increase the salinity tolerance of the primary surfactants and, in theory, allow tailoring of the surfactant system to match selected reservoir conditions. The experiments conducted included interfacial tension (IFT) measurements, phase behavior measurements, adsorption and/or chromatographic separation of mixed surfactant systems, measurements of solution properties such as the critical micelle concentration (CMC) of surfactant mixtures, and crude oil displacement experiments. The effects of temperature, surfactant concentration, salinity, presence of divalent ions, hydrocarbon type, and component proportions in the mixed surfactant combinations, and injection strategies on the performance potential of the targeted surfactant/hydrocarbon systems were studied. 40 refs., 37 figs., 8 tabs.

  13. Finite temperature reservoir engineering and entanglement dynamics

    E-Print Network [OSTI]

    S. Fedortchenko; A. Keller; T. Coudreau; P. Milman

    2014-05-29T23:59:59.000Z

    We propose experimental methods to engineer reservoirs at arbitrary temperature which are feasible with current technology. Our results generalize to mixed states the possibility of quantum state engineering through controlled decoherence. Finite temperature engineered reservoirs can lead to the experimental observation of thermal entanglement --the appearance and increase of entanglement with temperature-- to the study of the dependence of finite time disentanglement and revival with temperature, quantum thermodynamical effects, among many other applications, enlarging the comprehension of temperature dependent entanglement properties.

  14. Text-Alternative Version: MSSLC Member Case Studies- LED Street Lighting Programs Webinar

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "MSSLC Member Case Studies - LED Street Lighting Programs" webcast, held May 8, 2013.

  15. Text Alternative Version: Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products" webcast, held March 28, 2013.

  16. New Family of Tiny Crystals Glow Bright in LED Lights | Advanced...

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

    crystals that glow different colors may be the missing ingredient for white light-emitting diode (LED) lighting that illuminates homes and offices as effectively as natural...

  17. Scalable Light Module for Low-Cost, High Efficiency LED Luminaires...

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

    Low-Cost, High Efficiency LED Luminaires More Documents & Publications Low-Cost Light-Emitting Diode Luminaire for General Illumination 2015 Project Portfolio 2014 Solid-State...

  18. Text-Alternative Version: CALiPER Series 21 on LED Linear Lamps and Troffer Lighting

    Broader source: Energy.gov [DOE]

    Following is a text version of a video about CALiPER Application Report Series 21 on LED Linear Lamps and Troffer Lighting.

  19. Text-Alternative Version: LED Replacement Lamps: Current Performance and the Latest on ENERGY STAR®

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the LED Replacement Lamps: Current Performance and the Latest on ENERGY STAR® webcast.

  20. LED Linear Lamps and Troffer Lighting: CALiPER Report Series 21

    ScienceCinema (OSTI)

    Beeson, Tracy; Miller, Naomi

    2014-06-23T23:59:59.000Z

    Video about CALiPER Report Series 21 on LED Linear Lamps and Troffer Lighting, featuring interviews with Tracy Beeson and Naomi Miller of Pacific Northwest National Laboratory.

  1. Researchers Say They've Solved the Mystery of LED Lighting "Droop...

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

    Sciences Team. Despite being cool, ultra-efficient and long lasting, the light-emitting diode (LED) faces a problem called "efficiency droop." New findings from simulations...

  2. LEDS Tool: Step-By-Step Guidance to a Long-Term Framework for...

    Open Energy Info (EERE)

    OpenEI Keyword(s): LEDS Guidance Developing Implementing Process Language: "English, Spanish; Castilian" is not in the list of possible values (Abkhazian, Achinese, Acoli,...

  3. 2015 DOE SSL R&D Workshop LED Topic Table Questions to Consider

    Broader source: Energy.gov [DOE]

    This document was distributed during the LED Topic Table portion of the DOE SSL R&D Workshop and aimed to prompt discussion on the following topics:

  4. NUCLEAR MIXING METERS FOR CLASSICAL NOVAE

    SciTech Connect (OSTI)

    Kelly, Keegan J.; Iliadis, Christian; Downen, Lori; Champagne, Art [Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255 (United States); José, Jordi [Departament de Física i Enginyeria Nuclear, EUETIB, Universitat Politčcnica de Catalunya, E-08036 Barcelona (Spain)

    2013-11-10T23:59:59.000Z

    Classical novae are caused by mass transfer episodes from a main-sequence star onto a white dwarf via Roche lobe overflow. This material possesses angular momentum and forms an accretion disk around the white dwarf. Ultimately, a fraction of this material spirals in and piles up on the white dwarf surface under electron-degenerate conditions. The subsequently occurring thermonuclear runaway reaches hundreds of megakelvin and explosively ejects matter into the interstellar medium. The exact peak temperature strongly depends on the underlying white dwarf mass, the accreted mass and metallicity, and the initial white dwarf luminosity. Observations of elemental abundance enrichments in these classical nova events imply that the ejected matter consists not only of processed solar material from the main-sequence partner but also of material from the outer layers of the underlying white dwarf. This indicates that white dwarf and accreted matter mix prior to the thermonuclear runaway. The processes by which this mixing occurs require further investigation to be understood. In this work, we analyze elemental abundances ejected from hydrodynamic nova models in search of elemental abundance ratios that are useful indicators of the total amount of mixing. We identify the abundance ratios ?CNO/H, Ne/H, Mg/H, Al/H, and Si/H as useful mixing meters in ONe novae. The impact of thermonuclear reaction rate uncertainties on the mixing meters is investigated using Monte Carlo post-processing network calculations with temperature-density evolutions of all mass zones computed by the hydrodynamic models. We find that the current uncertainties in the {sup 30}P(p, ?){sup 31}S rate influence the Si/H abundance ratio, but overall the mixing meters found here are robust against nuclear physics uncertainties. A comparison of our results with observations of ONe novae provides strong constraints for classical nova models.

  5. ADVANCED MIXING MODELS

    SciTech Connect (OSTI)

    Lee, S; Richard Dimenna, R; David Tamburello, D

    2008-11-13T23:59:59.000Z

    The process of recovering the waste in storage tanks at the Savannah River Site (SRS) typically requires mixing the contents of the tank with one to four dual-nozzle jet mixers located within the tank. The typical criteria to establish a mixed condition in a tank are based on the number of pumps in operation and the time duration of operation. To ensure that a mixed condition is achieved, operating times are set conservatively long. This approach results in high operational costs because of the long mixing times and high maintenance and repair costs for the same reason. A significant reduction in both of these costs might be realized by reducing the required mixing time based on calculating a reliable indicator of mixing with a suitably validated computer code. The work described in this report establishes the basis for further development of the theory leading to the identified mixing indicators, the benchmark analyses demonstrating their consistency with widely accepted correlations, and the application of those indicators to SRS waste tanks to provide a better, physically based estimate of the required mixing time. Waste storage tanks at SRS contain settled sludge which varies in height from zero to 10 ft. The sludge has been characterized and modeled as micron-sized solids, typically 1 to 5 microns, at weight fractions as high as 20 to 30 wt%, specific gravities to 1.4, and viscosities up to 64 cp during motion. The sludge is suspended and mixed through the use of submersible slurry jet pumps. To suspend settled sludge, water is added to the tank as a slurry medium and stirred with the jet pump. Although there is considerable technical literature on mixing and solid suspension in agitated tanks, very little literature has been published on jet mixing in a large-scale tank. If shorter mixing times can be shown to support Defense Waste Processing Facility (DWPF) or other feed requirements, longer pump lifetimes can be achieved with associated operational cost and schedule savings. The focus of the present work is to establish mixing criteria associated with the waste processing at SRS and to quantify the mixing time required to suspend sludge particles with the submersible jet pump. Literature results for a turbulent jet flow are reviewed briefly, since the decay of the axial jet velocity and the evolution of the jet flow patterns are important phenomena affecting sludge suspension and mixing operations. One of the main objectives in the waste processing is to provide the DWPF a uniform slurry composition at a certain weight percentage (typically {approx}13 wt%) over an extended period of time. In preparation of the sludge for slurrying to DWPF, several important questions have been raised with regard to sludge suspension and mixing of the solid suspension in the bulk of the tank: (1) How much time is required to prepare a slurry with a uniform solid composition for DWPF? (2) How long will it take to suspend and mix the sludge for uniform composition in any particular waste tank? (3) What are good mixing indicators to answer the questions concerning sludge mixing stated above in a general fashion applicable to any waste tank/slurry pump geometry and fluid/sludge combination? Grenville and Tilton (1996) investigated the mixing process by giving a pulse of tracer (electrolyte) through the submersible jet nozzle and by monitoring the conductivity at three locations within the cylindrical tank. They proposed that the mixing process was controlled by the turbulent kinetic energy dissipation rate in the region far away from the jet entrance. They took the energy dissipation rates in the regions remote from the nozzle to be proportional to jet velocity and jet diameter at that location. The reduction in the jet velocity was taken to be proportional to the nozzle velocity and distance from the nozzle. Based on their analysis, a correlation was proposed. The proposed correlation was shown to be valid over a wide range of Reynolds numbers (50,000 to 300,000) with a relative standard deviation of {+-} 11.83%. An improved correlat

  6. Temperature, Temperature, Earth, geotherm for

    E-Print Network [OSTI]

    Treiman, Allan H.

    Temperature, Temperature, Earth, geotherm for total global heat flow Venus, geotherm for total global heat flow, 500 Ma #12;Temperature, Temperature, #12;Earth's modern regional continental geotherms Venusian Geotherms, 500 Ma Temperature, Temperature, After Blatt, Tracy, and Owens Petrology #12;Ca2Mg5Si8

  7. Turbulence and turbulent mixing in natural fluids

    E-Print Network [OSTI]

    Gibson, Carl H

    2010-01-01T23:59:59.000Z

    Turbulence and turbulent mixing in natural fluids begins with big bang turbulence powered by spinning combustible combinations of Planck particles and Planck antiparticles. Particle prograde accretion on a spinning pair releases 42% of the particle rest mass energy to produce more fuel for turbulent combustion. Negative viscosity and negative turbulence stresses work against gravity, creating mass-energy and space-time from the vacuum. Turbulence mixes cooling temperatures until a quark-gluon strong-force SF freeze-out. Gluon-viscosity anti-gravity ({\\Lambda}SF) exponentially inflates the fireball to preserve big bang turbulence information at scales larger than ct as the first fossil turbulence. Cosmic microwave background CMB temperature anisotropies show big bang turbulence fossils along with fossils of weak plasma turbulence triggered (10^12 s) as plasma viscous forces permit gravitational fragmentation on supercluster to galaxy mass scales (10^13 s). Turbulent morphologies and viscous-turbulent lengths a...

  8. Mixed anion materials and compounds for novel proton conducting membranes

    DOE Patents [OSTI]

    Poling, Steven Andrew; Nelson, Carly R.; Martin, Steve W.

    2006-09-05T23:59:59.000Z

    The present invention provides new amorphous or partially crystalline mixed anion chalcogenide compounds for use in proton exchange membranes which are able to operate over a wide variety of temperature ranges, including in the intermediate temperature range of about 100 .degree. C. to 300.degree. C., and new uses for crystalline mixed anion chalcogenide compounds in such proton exchange membranes. In one embodiment, the proton conductivity of the compounds is between about 10.sup.-8 S/cm and 10.sup.-1 S/cm within a temperature range of between about -60 and 300.degree. C. and a relative humidity of less than about 12%..

  9. Mixed waste: Proceedings

    SciTech Connect (OSTI)

    Moghissi, A.A.; Blauvelt, R.K.; Benda, G.A.; Rothermich, N.E. [eds.] [Temple Univ., Philadelphia, PA (United States). Dept. of Environmental Safety and Health

    1993-12-31T23:59:59.000Z

    This volume contains the peer-reviewed and edited versions of papers submitted for presentation a the Second International Mixed Waste Symposium. Following the tradition of the First International Mixed Waste Symposium, these proceedings were prepared in advance of the meeting for distribution to participants. The symposium was organized by the Mixed Waste Committee of the American Society of Mechanical Engineers. The topics discussed at the symposium include: stabilization technologies, alternative treatment technologies, regulatory issues, vitrification technologies, characterization of wastes, thermal technologies, laboratory and analytical issues, waste storage and disposal, organic treatment technologies, waste minimization, packaging and transportation, treatment of mercury contaminated wastes and bioprocessing, and environmental restoration. Individual abstracts are catalogued separately for the data base.

  10. Mixing by Swimming Algae

    E-Print Network [OSTI]

    Guasto, Jeffrey S; Gollub, J P; Pesci, Adriana I; Goldstein, Raymond E

    2009-01-01T23:59:59.000Z

    In this fluid dynamics video, we demonstrate the microscale mixing enhancement of passive tracer particles in suspensions of swimming microalgae, Chlamydomonas reinhardtii. These biflagellated, single-celled eukaryotes (10 micron diameter) swim with a "breaststroke" pulling motion of their flagella at speeds of about 100 microns/s and exhibit heterogeneous trajectory shapes. Fluorescent tracer particles (2 micron diameter) allowed us to quantify the enhanced mixing caused by the swimmers, which is relevant to suspension feeding and biogenic mixing. Without swimmers present, tracer particles diffuse slowly due solely to Brownian motion. As the swimmer concentration is increased, the probability density functions (PDFs) of tracer displacements develop strong exponential tails, and the Gaussian core broadens. High-speed imaging (500 Hz) of tracer-swimmer interactions demonstrates the importance of flagellar beating in creating oscillatory flows that exceed Brownian motion out to about 5 cell radii from the swimm...

  11. Effect of mixing on polymerization of styrene 

    E-Print Network [OSTI]

    Treybig, Michael Norris

    1977-01-01T23:59:59.000Z

    was performed by co- feeding styrene monomer, batch prepared living polystyrllithium seed and benzene. Reaction conditions such as temperature, initial monomer and polymer concentrations, residence time and mixing speed were varied to achieve different... for the laboratory reactor. Micromixing was found to pro- duce a broad distribution with a high molecular weight tail, whereas total segregation would produce a more narrow polymer distribution with a low molecular weight tail. Before making the laboratory...

  12. Process for etching mixed metal oxides

    DOE Patents [OSTI]

    Ashby, C.I.H.; Ginley, D.S.

    1994-10-18T23:59:59.000Z

    An etching process is described using dicarboxylic and tricarboxylic acids as chelating etchants for mixed metal oxide films such as high temperature superconductors and ferroelectric materials. Undesirable differential etching rates between different metal oxides are avoided by selection of the proper acid or combination of acids. Feature sizes below one micron, excellent quality vertical edges, and film thicknesses in the 100 Angstrom range may be achieved by this method. 1 fig.

  13. Process for etching mixed metal oxides

    DOE Patents [OSTI]

    Ashby, Carol I. H. (Edgewood, NM); Ginley, David S. (Evergreen, CO)

    1994-01-01T23:59:59.000Z

    An etching process using dicarboxylic and tricarboxylic acids as chelating etchants for mixed metal oxide films such as high temperature superconductors and ferroelectric materials. Undesirable differential etching rates between different metal oxides are avoided by selection of the proper acid or combination of acids. Feature sizes below one micron, excellent quality vertical edges, and film thicknesses in the 100 Angstom range may be achieved by this method.

  14. Mixed crystal organic scintillators

    DOE Patents [OSTI]

    Zaitseva, Natalia P; Carman, M Leslie; Glenn, Andrew M; Hamel, Sebastien; Hatarik, Robert; Payne, Stephen A; Stoeffl, Wolfgang

    2014-09-16T23:59:59.000Z

    A mixed organic crystal according to one embodiment includes a single mixed crystal having two compounds with different bandgap energies, the organic crystal having a physical property of exhibiting a signal response signature for neutrons from a radioactive source, wherein the signal response signature does not include a significantly-delayed luminescence characteristic of neutrons interacting with the organic crystal relative to a luminescence characteristic of gamma rays interacting with the organic crystal. According to one embodiment, an organic crystal includes bibenzyl and stilbene or a stilbene derivative, the organic crystal having a physical property of exhibiting a signal response signature for neutrons from a radioactive source.

  15. TRUE COLORS: LEDS AND THE RELATIONSHIP BETWEEN CCT, CRI, OPTICAL SAFETY, MATERIAL DEGRADATION, AND PHOTOBIOLOGICAL STIMULATION

    SciTech Connect (OSTI)

    Royer, Michael P.

    2014-08-30T23:59:59.000Z

    This document analyzes the optical, material, and photobiological hazards of LED light sources compared to conventional light sources. It documents that LEDs generally produce the same amount of blue light, which is the primary contributor to the risks, as other sources at the same CCT. Duv may have some effect on the amount of blue light, but CRI does not.

  16. The evolving price of household LED lamps: Recent trends and historical comparisons for the US market

    SciTech Connect (OSTI)

    Gerke, Brian F.; Ngo, Allison T.; Alstone, Andrea L.; Fisseha, Kibret S.

    2014-10-14T23:59:59.000Z

    In recent years, household LED light bulbs (LED A lamps) have undergone a dramatic price decline. Since late 2011, we have been collecting data, on a weekly basis, for retail offerings of LED A lamps on the Internet. The resulting data set allows us to track the recent price decline in detail. LED A lamp prices declined roughly exponentially with time in 2011-2014, with decline rates of 28percent to 44percent per year depending on lumen output, and with higher-lumen lamps exhibiting more rapid price declines. By combining the Internet price data with publicly available lamp shipments indices for the US market, it is also possible to correlate LED A lamp prices against cumulative production, yielding an experience curve for LED A lamps. In 2012-2013, LED A lamp prices declined by 20-25percent for each doubling in cumulative shipments. Similar analysis of historical data for other lighting technologies reveals that LED prices have fallen significantly more rapidly with cumulative production than did their technological predecessors, which exhibited a historical decline of 14-15percent per doubling of production.

  17. CONSTRUCTING AN ELASTIC TOUCH PANEL WITH EMBEDDED IR-LEDS USING SILICONE RUBBER

    E-Print Network [OSTI]

    Tanaka, Jiro

    CONSTRUCTING AN ELASTIC TOUCH PANEL WITH EMBEDDED IR-LEDS USING SILICONE RUBBER Yuichiro Sakamoto a technique for the construction of an elastic touch panel using silicone rubber. The technique is similar is made of transparent silicone rubber rather than acrylic. Moreover, we embedded infrared LEDs within

  18. Department of Mechanical Engineering Spring 2013 Lumax Lighting 2: LED Industrial High Bay Light Fixture

    E-Print Network [OSTI]

    Demirel, Melik C.

    PENNSTATE Department of Mechanical Engineering Spring 2013 Lumax Lighting 2: LED Industrial High Bay Light Fixture Overview The problem that our sponsor, Rich Taylor, presented to the team was to design a light fixture for an industrial setting using high power LED lights. The challenge

  19. Cree's High-Power White LED Delivers 121 lm/W

    Broader source: Energy.gov [DOE]

    Cree's commercial high-power white LEDs can now deliver 121 lm/W at 35A/cm2 current density. These particular Cree XLamp® XP-G LEDs deliver 267 lumens at a drive current of 700 mA and an operating...

  20. LED Lighting Flicker and Potential Health Concerns: IEEE Standard PAR1789 Update

    E-Print Network [OSTI]

    Lehman, Brad

    LED Lighting Flicker and Potential Health Concerns: IEEE Standard PAR1789 Update Arnold Wilkins for mitigating health risks to viewers" has been formed to advise the lighting industry, ANSI/NEMA, IEC, EnergyStar and other standards groups about the emerging concern of flicker in LED lighting. This paper introduces

  1. Proposal -Interactive City Lighting LED based lighting systems have enabled radically new

    E-Print Network [OSTI]

    Proposal - Interactive City Lighting Abstract LED based lighting systems have also be integrated with sensors and smart environments. This has opened up a new world. The use of the LED as a potential means for providing interactive city lighting for social

  2. Largest-area Photonic Crystal LED Fabricated Demonstrates Uniform Light Emission

    Broader source: Energy.gov [DOE]

    Lumileds Lighting, the University of New Mexico, and Sandia National Laboratories teamed to demonstrate uniform light emission from the largest-area III-Nitride photonic crystal LED (1 x 1 mm2) ever fabricated. Most previous photonic crystal LED research has relied on small-area patterns written by slow, serial-writing electron-beam lithography.

  3. An Efficient LED System-in-Module for General Lighting Applications

    SciTech Connect (OSTI)

    None

    2008-09-14T23:59:59.000Z

    The objective of the project was to realize an LED-based lighting technology platform for general illumination, starting with LED chips, and integrating the necessary technologies to make compact, user-friendly, high-efficiency, energy-saving sources of controlled white (or variable-colored) light. The project is to build the system around the LEDs, and not to work on the LEDs themselves, in order that working products can be introduced soon after the LEDs reach suitable efficiency for mass-production of high-power light sources for general illumination. Because the light sources are intended for general illumination, color must be accurately maintained, requiring feedback control in the electronics. The project objective has been realized and screw base demonstrators, based on the technology developed in the project, have been built.

  4. Unitarity constraints on trimaximal mixing

    SciTech Connect (OSTI)

    Kumar, Sanjeev [Department of Physics and Astrophysics, University of Delhi, Delhi -110005 (India)

    2010-07-01T23:59:59.000Z

    When the neutrino mass eigenstate {nu}{sub 2} is trimaximally mixed, the mixing matrix is called trimaximal. The middle column of the trimaximal mixing matrix is identical to tribimaximal mixing and the other two columns are subject to unitarity constraints. This corresponds to a mixing matrix with four independent parameters in the most general case. Apart from the two Majorana phases, the mixing matrix has only one free parameter in the CP conserving limit. Trimaximality results in interesting interplay between mixing angles and CP violation. A notion of maximal CP violation naturally emerges here: CP violation is maximal for maximal 2-3 mixing. Similarly, there is a natural constraint on the deviation from maximal 2-3 mixing which takes its maximal value in the CP conserving limit.

  5. Optical Wireless based on High Brightness Visible LEDs Grantham Pang, Thomas Kwan, Hugh Liu, Chi-Ho Chan

    E-Print Network [OSTI]

    Pang, Grantham

    and encoded with audio or data signal. Hence, an LED indicator lamp or traffic light can become an information for incandescent lamps [3,4]. This advancement has led to the production of large- area full-color LED displaysOptical Wireless based on High Brightness Visible LEDs Grantham Pang, Thomas Kwan, Hugh Liu, Chi

  6. 78.1: Ultra Compact Polarization Recycling System for White Light LED based Pico-Projection System

    E-Print Network [OSTI]

    78.1: Ultra Compact Polarization Recycling System for White Light LED based Pico-Projection System polarization recycling system, for white light LED based projectors, is proposed. White light LED is applied. In this paper, we propose an ultra compact polarization recycling system for white light LED based projection

  7. Quality and Performance of LED Flashlights in Kenya: Common End User Preferences and Complaints

    SciTech Connect (OSTI)

    Tracy, Jenny; Jacobson, Arne; Mills, Evan

    2009-09-14T23:59:59.000Z

    Flashlights that use LED technology have quickly emerged as the dominant source of portable lighting in Kenya. While flashlights do not normally provide a substitute for kerosene and other highly inefficient fuels, they are an important early manifestation of LED lighting in the developing world that can serve as a platform - or deterrent - to the diffusion of the technology into the broader off-grid lighting market. The lead acid batteries embedded in flashlights also represent an important source of hazardous waste, and flashlight durability is thus an important determinant of the rate of waste disposal. Low-cost LED flashlights with prices from $1 to $4 are now widely available in shops and markets throughout Kenya. The increased penetration of LED technology in the flashlight market is significant, as over half of all Kenyan households report owning a flashlight (Kamfor, 2002). While this shift from conventional incandescent technology to modern LEDs may appear to be a promising development, end users that our research team interviewed expressed a number of complaints about the quality and performance of these new flashlights. This raises concerns about the interests of low-income flashlight users, and it may also indicate the onset of a broader market spoiling effect for off-grid lighting products based on LED technology (Mills and Jacobson, 2008; Lighting Africa, 2007). The quality of low-cost LED flashlights can contribute to market spoiling because these products appear to represent the first contact that most Kenyans have with LED technology. In this report, our team uses interviews with 46 end users of flashlights to collect information about their experiences, perceptions, and preferences. We focus especially on highlighting common complaints from respondents about the flashlights that they have used, as well as on noting the features that they indicated were important when evaluating the quality of a flashlight. In previous laboratory tests, researchers from our team found a wide range of quality and performance among battery powered LED lights (Granderson, et al. 2008).

  8. Novel physical solvents for selective CO{sub 2} capture from fuel gas streams at elevated pressures and temperatures

    SciTech Connect (OSTI)

    Yannick J. Heintz; Laurent Sehabiague; Badie I. Morsi; Kenneth L. Jones; Henry W. Pennline [United States Department of Energy (DOE), Pittsburgh, PA (United States). National Energy Technology Laboratory

    2008-11-15T23:59:59.000Z

    Three perfluorinated compounds (PFCs), PP10, PP11, and PP25, manufactured by F2 Chemicals Ltd., U.K., were investigated as physical solvents for selective CO{sub 2} capture from synthesis gas or syngas streams at elevated pressures and temperatures. The equilibrium solubility, the hydrodynamic, and the mass-transfer parameters of CO{sub 2} in the solvents were measured in a 4-L ZipperClave agitated reactor under wide ranges of operating conditions: pressures (6-30 bar), temperatures (300-500 K), mixing speeds (10-20 Hz), and liquid heights (0.14-0.22 m). The CO{sub 2} solubilities in the three solvents decreased with an increasing temperature at constant pressure and followed Henry's law. The CO{sub 2} solubilities in PP25 were greater than those in PP10 and PP11. The volumetric liquid-side mass-transfer coefficients (k{sub La}) of CO{sub 2} in the PFCs increased with mixing speed, pressure, and temperature. Also, the gas-liquid interfacial areas of CO{sub 2} in the three PFCs appeared to control the behavior of k{sub La}. This study proved the thermal and chemical stability and the ability of the PFCs to selectively absorb CO{sub 2} at temperatures up to 500 K and pressures as high as 30 bar. A preliminary conceptual process design using PP25 for selective CO{sub 2} capture from hot-shifted gas with pressure-swing and pressure-temperature-swing regeneration options was devised. The pressure-temperature-swing option led to greater PP25 solvent loss but a more favorable (more negative) net enthalpy than the pressure-swing option. However, for either regeneration option to be economically viable, the PP25 solvent must be completely recovered from the process. 109 refs., 9 figs., 14 tabs.

  9. A Study of mixing in computer simulated laminar flow systems 

    E-Print Network [OSTI]

    McFarland, Allison Anne

    1984-01-01T23:59:59.000Z

    1984 Major Subject: Chemical Engineering A STUDY OF MIXING IN COMPUTER SIMULATED LAMINAR FLOW SYSTEMS A Thesis by ALLISON ANNE MCFARLAND Approved as to style and content by: Gary B. Tatterson (Chairman) ries J. Glover (Member) A. Ted Watson...: Dr. Gary B. Tatterson Mixing is a process that reduces nonuniformities or gradients in composition, properties, or temperature of material in bulk. It is a basic part of many chemical engineering processes, yet the theoretical understanding...

  10. Vapochromic LED

    DOE Patents [OSTI]

    Kunugi, Yoshihito (Hiroshima, JP); Mann, Kent R. (North Oaks, MN); Miller, Larry L. (Minnetonka, MN); Exstrom, Christopher L. (Kearney, NE)

    2003-06-17T23:59:59.000Z

    A sandwich device was prepared by electrodeposition of an insoluble layer of oligomerized tris(4-(2-thienyl)phenyl)amine onto conducting indium-tin oxide coated glass, spin coating the stacked platinum compound, tetrakis(p-decylphenylisocyano)platinum tetranitroplatinate, from toluene onto the oligomer layer, and then coating the platinum complex with aluminum by vapor deposition. This device showed rectification of current and gave electroluminescence. The electroluminescence spectrum (.lambda..sub.max =545 nm) corresponded to the photoluminescence spectrum of the platinum complex. Exposure of the device to acetone vapor caused the electroemission to shift to 575 nm. Exposure to toluene vapor caused a return to the original spectrum. These results demonstrate a new type of sensor that reports the arrival of organic vapors with an electroluminescent signal. The sensor comprises (a) a first electrode; (b) a hole transport layer formed on the first electrode; (c) a sensing/emitting layer formed on the hole transport layer, the sensing/emitting layer comprising a material that changes color upon exposure to the analyte vapors; (d) an electron conductor layer formed on the sensing layer; and (e) a second electrode formed on the electron conductor layer. The hole transport layer emits light at a shorter wavelength than the sensing/emitting layer and at least the first electrode comprises an optically transparent material.

  11. Vapochromic LED

    DOE Patents [OSTI]

    Kunugi, Yoshihito (Hiroshima, JP); Mann, Kent R. (North Oaks, MN); Miller, Larry L. (Minnetonka, MN); Exstrom, Christopher L. (Kearney, NE)

    2002-01-15T23:59:59.000Z

    A sandwich device was prepared by electrodeposition of an insoluble layer of oligomerized tris(4-(2-thienyl)phenyl)amine onto conducting indium-tin oxide coated glass, spin coating the stacked platinum compound, tetrakis(p-decylphenylisocyano)platinum tetranitroplatinate, from toluene onto the oligomer layer, and then coating the platinum complex with aluminum by vapor deposition. This device showed rectification of current and gave electroluminescence. The electroluminescence spectrum (.mu..sub.max =545 nm) corresponded to the photoluminescence spectrum of the platinum complex. Exposure of the device to acetone vapor caused the electroemission to shift to 575 nm. Exposure to toluene vapor caused a return to the original spectrum. These results demonstrate a new type of sensor that reports the arrival of organic vapors with an electroluminescent signal. The sensor comprises (a) a first electrode; (b) a hole transport layer formed on the first electrode; (c) a sensing/emitting layer formed on the hole transport layer, the sensing/emitting layer comprising a material that changes color upon exposure to the analyte vapors; (d) an electron conductor layer formed on the sensing layer; and (e) a second electrode formed on the electron conductor layer. The hole transport layer emits light at a shorter wavelength than the sensing/emitting layer and at least the first electrode comprises an optically transparent material.

  12. Philips Lumileds Is Exploring the Use of Silicon Substrates to Lower the Cost of LEDs

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, Philips Lumileds is exploring the use of nitride epitaxy on 150mm silicon substrates to produce low-cost, warm-white, high-performance general-illumination LEDs. Most LEDs are made with C-plane sapphire substrates, but silicon—at roughly half a penny per square millimeter—is much cheaper, and it's also easier to obtain. Philips Lumileds is attempting to adapt the use of silicon to the manufacture of LEDs, drawing upon the knowledge base and depreciated equipment of the computer industry, which has been using silicon substrates for decades.

  13. High Efficiency m-plane LEDs on Low Defect Density Bulk GaN Substrates

    SciTech Connect (OSTI)

    David, Aurelien

    2012-10-15T23:59:59.000Z

    Solid-state lighting is a key technology for reduction of energy consumption in the US and worldwide. In principle, by replacing standard incandescent bulbs and other light sources with sources based on light-emitting diodes (LEDs), ultimate energy efficiency can be achieved. The efficiency of LEDs has improved tremendously over the past two decades, however further progress is required for solid- state lighting to reach its full potential. The ability of an LED at converting electricity to light is quantified by its internal quantum efficiency (IQE). The material of choice for visible LEDs is Gallium Nitride (GaN), which is at the basis of blue-emitting LEDs. A key factor limiting the performance of GaN LEDs is the so-called efficiency droop, whereby the IQE of the LED decreases significantly at high current density. Despite decades of research, efficiency droop remains a major issue. Since high-current operation is necessary for practical lighting applications, reducing droop is a major challenge for the scientific community and the LED industry. Our approach to solving the droop issue is the use of newly available low-defect-density bulk GaN non-polar substrates. In contrast to the standard foreign substrates (sapphire, silicon carbide, silicon) used in the industry, we have employed native bulk GaN substrates with very low defect density, thus ensuring exquisite material quality and high IQE. Whereas all commercial LEDs are grown along the c-plane crystal direction of GaN, we have used m-plane non-polar substrates; these drastically modify the physical properties of the LED and enable a reduction of droop. With this approach, we have demonstrated very high IQE performance and low droop. Our results focused on violet and blue LEDs. For these, we have demonstrated very high peak IQEs and current droops of 6% and 10% respectively (up to a high current density of 200A.cm-2). All these results were obtained under electrical operation. These high IQE and low droop values are in line with the program’s milestones. They demonstrate that bulk non-polar GaN substrates represent a disruptive technology for LED performance. Application of this technology to real-world products is feasible, provided that the cost of GaN substrates is compatible with the market’s requirement.

  14. LED Provides Effective and Efficient Parking Area Lighting at the NAVFAC Engineering Service Center

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED LightingOutdoorLED

  15. 13. Neutrino mixing 1 13. NEUTRINO MASS, MIXING, AND OSCILLATIONS

    E-Print Network [OSTI]

    13. Neutrino mixing 1 13. NEUTRINO MASS, MIXING, AND OSCILLATIONS Updated May 2012 by K. Nakamura have provided compelling evidences for oscillations of neutrinos caused by nonzero neutrino masses of neutrino oscillations, the phenomenology of neutrino mixing, the problem of the nature - Dirac or Majorana

  16. Scientists ignite aluminum water mix

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

    Scientists ignite aluminum water mix Scientists ignite aluminum water mix Don't worry, that beer can you're holding is not going to spontaneously burst into flames. June 30, 2014...

  17. Nozzle mixing apparatus

    SciTech Connect (OSTI)

    Mensink, D.L.

    1992-12-31T23:59:59.000Z

    This invention is comprised of a nozzle device for causing two fluids to mix together. In particular, a spray nozzle comprise two hollow, concentric housings, an inner housing and an outer housing. The inner housing has a channel formed therethrough for a first fluid. Its outer surface cooperates with the interior surface of the outer housing to define the second channel for a second fluid. The outer surface of the inner housing and the inner surface of the outer housing each carry a plurality of vanes that interleave but do not touch, each vane of one housing being between two vanes of the other housing. The vanes are curved and the inner surface of the outer housing and the outer surface of the inner housing converge to narrow the second channel. The shape of second channel results in a swirling, accelerating second fluid that will impact the first fluid just past the end of the nozzle where mixing will take place.

  18. Cosmological Kinetic Mixing

    E-Print Network [OSTI]

    Ashok Das; Jorge Gamboa; Miguel Pino

    2015-04-15T23:59:59.000Z

    In this paper we generalize the kinetic mixing idea to time reparametrization invariant theories, namely, relativistic point particles and cosmology in order to obtain new insights for dark matter and energy. In the first example, two relativistic particles interact through an appropriately chosen coupling term. It is shown that the system can be diagonalized by means of a non-local field redefinition, and, as a result of this procedure, the mass of one the particles gets rescaled. In the second case, inspired by the previous example, two cosmological models (each with its own scale factor) are made to interact in a similar fashion. The equations of motion are solved numerically in different scenarios (dust, radiation or a cosmological constant coupled to each sector of the system). When a cosmological constant term is present, kinetic mixing rescales it to a lower value which may be more amenable to observations.

  19. Coolant mixing in LMFBR rod bundles and outlet plenum mixing transients. Final report

    SciTech Connect (OSTI)

    Todreas, N.E.; Cheng, S.K.; Basehore, K.

    1984-08-01T23:59:59.000Z

    This project principally undertook the investigation of the thermal hydraulic performance of wire wrapped fuel bundles of LMFBR configuration. Results obtained included phenomenological models for friction factors, flow split and mixing characteristics; correlations for predicting these characteristics suitable for insertion in design codes; numerical codes for analyzing bundle behavior both of the lumped subchannel and distributed parameter categories and experimental techniques for pressure velocity, flow split, salt conductivity and temperature measurement in water cooled mockups of bundles and subchannels. Flow regimes investigated included laminar, transition and turbulent flow under forced convection and mixed convection conditions. Forced convections conditions were emphasized. Continuing efforts are underway at MIT to complete the investigation of the mixed convection regime initiated here. A number of investigations on outlet plenum behavior were also made. The reports of these investigations are identified.

  20. Member Case Studies: LED Street Lighting Programs in Algona (IA), Asheville (NC), and Boston (MA)

    Broader source: Energy.gov [DOE]

    This May 8, 2013 webcast featured presentations from DOE Municipal Solid-State Street Lighting Consortium member cities about their experiences with LED street lighting. Presenters John Bilsten of...

  1. LED Linear Lamps and Troffer Lighting: CALiPER Report Series 21

    Broader source: Energy.gov [DOE]

    View the video about CALiPER Report Series 21 on LED Linear Lamps and Troffer Lighting, featuring interviews with Tracy Beeson and Naomi Miller of Pacific Northwest National Laboratory.

  2. Transcranial LED therapy for cognitive dysfunction in chronic, mild traumatic brain injury: Two case reports

    E-Print Network [OSTI]

    Hamblin, Michael R.

    Two chronic, traumatic brain injury (TBI) cases are presented, where cognitive function improved following treatment with transcranial light emitting diodes (LEDs). At age 59, P1 had closed-head injury from a motor vehicle ...

  3. Deposition of colloidal quantum dots by microcontact printing for LED display technology

    E-Print Network [OSTI]

    Kim, LeeAnn

    2006-01-01T23:59:59.000Z

    This thesis demonstrates a new deposition method of colloidal quantum dots within a quantum dot organic light-emitting diode (QD-LED). A monolayer of quantum dots is microcontact printed as small as 20 ,Lm lines as well ...

  4. Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products

    Broader source: Energy.gov [DOE]

    This March 28, 2013 webcast reviewed DOE's recently completed three-part study of the life-cycle energy and environmental impacts of LED lighting products relative to incandescent and CFL...

  5. Psychophysical evaluations of modulated color rendering for energy performance of LED-based architectural lighting

    E-Print Network [OSTI]

    Thompson, Maria do Rosário

    2007-01-01T23:59:59.000Z

    This thesis is focused on the visual perception evaluation of colors within an environment of a highly automated lighting control strategy. Digitally controlled lighting systems equipped with light emitting diodes, LEDs, ...

  6. Quality and Performance of LED Flashlights in Kenya: Common End User Preferences and Complaints

    E-Print Network [OSTI]

    Tracy, Jenny

    2010-01-01T23:59:59.000Z

    at ensure the success of the off-grid lighting market. Theand E. Mills. 2008. "Measured Off? Grid LED Lighting Systemtechnology into the broader off-grid lighting market. The

  7. adjustable red-green-blue led: Topics by E-print Network

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

    or by combining green and red phosphors on a background consisting of a blue-light emitting diode (LED) or by employing nanocrystals (NCs) of the three primary colors (red,...

  8. Text-Alternative Version: CALiPER Report Series 20 on LED PAR38 Lamps

    Broader source: Energy.gov [DOE]

    Michael Royer, Lighting Engineer, Pacific Northwest National Laboratory: The CALiPER program looks at typical LED lamp performance attributes. As we've gone through the progression of reports, we...

  9. DOE Publishes CALiPER Snapshot Report on LED MR16 Lamps

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released a Snapshot Report on MR16 lamps, which utilizes the LED Lighting Facts® program's extensive product database to help industry...

  10. Dimming LEDs with Phase-Cut Dimmers: The Specifier's Process for Maximizing Success

    SciTech Connect (OSTI)

    Miller, Naomi J.; Poplawski, Michael E.

    2013-10-01T23:59:59.000Z

    This report reviews how phase-cut dimmers work, how LEDs differ from the incandescent lamps that the dimmers were historically designed to control, and how these differences can lead to complications when trying to dim LEDs. Compatibility between a specific LED source and a specific phase-cut dimmer is often unknown and difficult to assess, and ensuring compatibility adds complexity to the design, specification, bidding, and construction observation phases for new buildings and major remodel projects. To maximize project success, this report provides both general guidance and step-by-step procedures for designing phase-controlled LED dimming on both new and existing projects, as well as real-world examples of how to use those procedures.

  11. DOE Publishes CALiPER Report on LED T8 Lamps

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released an Application Summary Report that focuses on the bare-lamp performance of 31 linear LED lamps intended as an alternative to T8...

  12. Collective Experience: A Database-Fuelled, Inter-Disciplinary Team-Led Learning System

    E-Print Network [OSTI]

    Celi, Leo Anthony G.

    We describe the framework of a data-fuelled, interdisciplinary team-led learning system. The idea is to build models using patients from one's own institution whose features are similar to an index patient as regards an ...

  13. Applied Materials Develops an Advanced Epitaxial Growth System to Bring Down LED Costs

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, Applied Materials has developed an advanced epitaxial growth system for gallium nitride (GaN) LED devices that decreases operating costs, increases internal quantum efficiency, and improves binning yields.

  14. Quality and Performance of LED Flashlights in Kenya: Common End User Preferences and Complaints

    E-Print Network [OSTI]

    Tracy, Jenny

    2010-01-01T23:59:59.000Z

    grid lighting market. The lead acid batteries embedded inrechargeable sealed lead-acid batteries are the most popularlead-acid (SLA) battery, LED flashlights powered by dry cell batteries,

  15. LED Replacement Lamps: Current Performance and the Latest on ENERGY STAR®

    Broader source: Energy.gov [DOE]

    This May 19, 2009 webcast summarized CALiPER's recent benchmark testing of common omnidirectional incandescent lamps (e.g., A-lamps), and provided an update on ENERGY STAR criteria for LED integral...

  16. Text-Alternative Version: LED Lighting in a Performing Arts Building Webinar

    Broader source: Energy.gov [DOE]

     Welcome ladies and gentlemen. I'm Bob Davis with the Pacific Northwest National Laboratory, and I'd like to welcome you to today's webcast titled, LEDs, Can They Perform in a Performing Arts...

  17. EECBG Success Story: Shining Energy-Saving LEDs on Utah Starry...

    Energy Savers [EERE]

    LEDs across 14 rural communities. About 2,500 streetlights will be replaced and could save the town 20% to 50% on electricity bills. Learn more. Addthis Related Articles A...

  18. Digital Architecture for Driving Large LED Arrays with Dynamic Bus Voltage Regulation and Phase Shifted PWM

    E-Print Network [OSTI]

    Emitting Diodes (HB-LEDs) with improved system efficiency and reduced EMI. Key advantages are achieved - This paper introduces a digital architecture suitable for driving a large number of High Brightness Light

  19. Successful Selection of LED Streetlight Luminaires: Optimizing Illumination and Economic Performance

    Broader source: Energy.gov [DOE]

    This March 6, 2013 webcast reviewed the factors involved in successful selection of LED streetlight luminaires. Presenters Eric Haugaard of Cree Lighting and Chad Stalker of Philips Lumileds guided...

  20. Two PPPL-led teams win increased supercomputing time to study...

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

    Two PPPL-led teams win increased supercomputing time to study conditions inside fusion plasmas By John Greenwald January 9, 2014 Tweet Widget Google Plus One Share on Facebook...

  1. Cooking with Dry Egg Mix

    E-Print Network [OSTI]

    Anding, Jenna

    2008-12-09T23:59:59.000Z

    package has been opened, place the unused egg mix in a resealable bag or in an airtight container and store it in the refrigerator. How to prepare it To make liquid eggs, stir 1 part mix with 2 parts warm water. Use a fork to blend the egg mix...

  2. Magnetically coupled system for mixing

    SciTech Connect (OSTI)

    Miller, III, Harlan; Meichel, George; Legere, Edward; Malkiel, Edwin; Woods, Robert Paul; Ashley, Oliver; Katz, Joseph; Ward, Jason; Petersen, Paul

    2014-04-01T23:59:59.000Z

    The invention provides a mixing system comprising a magnetically coupled drive system and a foil for cultivating algae, or cyanobacteria, in an open or enclosed vessel. The invention provides effective mixing, low energy usage, low capital expenditure, and ease of drive system component maintenance while maintaining the integrity of a sealed mixing vessel.

  3. Veeco Develops a Tool to Reduce Epitaxy Costs and Increase LED Brightness

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, Veeco is working on reducing epitaxy costs and increasing LED efficiency by developing a physical vapor deposition (PVD) tool for depositing aluminum nitride buffer layers on LED substrates. PVD, also known as "sputtering," is an alternative to metal-organic chemical vapor deposition (MOCVD). PVD is a purely physical process that involves plasma sputter bombardment rather than a chemical reaction at the surface to be coated, as in MOCVD.

  4. CALiPER Report 21.3: Cost-Effectiveness of Linear (T8) LED Lamps

    SciTech Connect (OSTI)

    Miller, Naomi J.; Perrin, Tess E.; Royer, Michael P.

    2014-05-27T23:59:59.000Z

    Meeting performance expectations is important for driving adoption of linear LED lamps, but cost-effectiveness may be an overriding factor in many cases. Linear LED lamps cost more initially than fluorescent lamps, but energy and maintenance savings may mean that the life-cycle cost is lower. This report details a series of life-cycle cost simulations that compared a two-lamp troffer using LED lamps (38 W total power draw) or fluorescent lamps (51 W total power draw) over a 10-year study period. Variables included LED system cost ($40, $80, or $120), annual operating hours (2,000 hours or 4,000 hours), LED installation time (15 minutes or 30 minutes), and melded electricity rate ($0.06/kWh, $0.12/kWh, $0.18/kWh, or $0.24/kWh). A full factorial of simulations allows users to interpolate between these values to aid in making rough estimates of economic feasibility for their own projects. In general, while their initial cost premium remains high, linear LED lamps are more likely to be cost-effective when electric utility rates are higher than average and hours of operation are long, and if their installation time is shorter.

  5. Assessment of LED Technology in Ornamental Post-Top Luminaires (Host Site: Sacramento, CA)

    SciTech Connect (OSTI)

    Tuenge, Jason R.

    2011-12-01T23:59:59.000Z

    The DOE Municipal Solid-State Street Lighting Consortium has evaluated four different LED replacements for existing ornamental post-top street lights in Sacramento, California. The project team was composed of the City and its consultant, PNNL (representing the Consortium), and the Sacramento Municipal Utility District. Product selection was finalized in March 2011, yielding one complete luminaire replacement and three lamp-ballast retrofit kits. Computer simulations, field measurements, and laboratory testing were performed to compare the performance and cost-effectiveness of the LED products relative to the existing luminaire with 100 W high-pressure sodium lamp. After it was confirmed the LED products were not equivalent to HPS in terms of initial photopic illumination, the following parameters were scaled proportionally to enable equitable (albeit hypothetical) comparisons: light output, input wattage, and pricing. Four replacement scenarios were considered for each LED product, incorporating new IES guidance for mesopic multipliers and lumen maintenance extrapolation, but life cycle analysis indicated cost effectiveness was also unacceptable. Although LED efficacy and pricing continue to improve, this project serves as a timely and objective notice that LED technology may not be quite ready yet for such applications.

  6. CALiPER Retail Lamps Study RRL3.2 Lumen and Chromaticity Maintenance of LED A lamps Operated in Steady-State Conditions

    SciTech Connect (OSTI)

    Royer, Michael P.; McCullough, Jeffrey J.; Tucker, Joseph C.

    2014-12-01T23:59:59.000Z

    The lumen depreciation and color shift of 17 different A lamps (15 LED, 1 CFL, 1 halogen) was monitored in the automated long-term test apparatus (ALTA) for more than 7,500 hours. Ten samples of each lamp model were tested, with measurements recorded on a weekly basis. The lamps were operated continuously at an ambient temperature of 45°C (-1°C). Importantly, the steady-state test conditions were not optimized for inducing catastrophic failure for any of the lamp technologies—to which thermal cycling is a strong contributor— and are not typical of normal use patterns—which usually include off periods where the lamp cools down. Further, the test conditions differ from those used in standardized long-term test methods (i.e., IES LM-80, IES LM-84), so the results should not be directly compared. On the other hand, the test conditions are similar to those used by ENERGY STAR (when elevated temperature testing is called for). Likewise, the conditions and assumptions used by manufacturers to generated lifetime claims may vary; the CALiPER long-term data is informative, but cannot necessarily be used to discredit manufacturer claims. The test method used for this investigation should be interpreted as one more focused on the long-term effects of elevated temperature operation, at an ambient temperature that is not uncommon in luminaires. On average, the lumen maintenance of the LED lamps monitored in the ALTA was better than benchmark lamps, but there was considerable variation from lamp model to lamp model. While three lamp models had average lumen maintenance above 99% at the end of the study period, two products had average lumen maintenance below 65%, constituting a parametric failure. These two products, along with a third, also exhibited substantial color shift, another form of parametric failure. While none of the LED lamps exhibited catastrophic failure—and all of the benchmarks did—the early degradation of performance is concerning, especially with a new technology trying to build a reputation with consumers. Beyond the observed parametric failures nearly half of the products failed to meet early-life thresholds for lumen maintenance, which were borrowed from ENERGY STAR specifications. That is, the lumen maintenance was sufficiently low at 6,000 hours that seven of the products are unlikely to have lumen maintenance above 70% at their rated lifetime (which was usually 25,000 hours). Given the methods used for this investigation—most notably continuous operation—the results should not be interpreted as indicative of a lamp’s performance in a typical environment. Likewise, these results are not directly relatable to manufacturer lifetime claims. This report is best used to understand the variation in LED product performance, compare the robustness of LED lamps and benchmark conventional lamps, and understand the characteristics of lumen and chromaticity change. A key takeaway is that the long-term performance of LED lamps can vary greatly from model to model (i.e., the technology is not homogenous), although the lamp-to-lamp consistency within a given model is relatively good. Further, operation of LED lamps in an enclosed luminaire (or otherwise in high ambient temperatures), can induce parametric failure of LEDs much earlier than their rated lifetime; manufacturer warnings about such conditions should be followed if performance degradation is unacceptable.

  7. Impact of photonic crystals on LED light extraction efficiency: approaches and limits to vertical structure designs

    SciTech Connect (OSTI)

    Matioli, Elison; Weisbuch, Claude

    2010-01-01T23:59:59.000Z

    The enhancement of the extraction efficiency in light emitting diodes (LEDs) through the use of photonic crystals (PhCs) requires a structure design that optimizes the interaction of the guided modes with the PhCs. The main optimization parameters are related to the vertical structure of the LED, such as the thickness of layers, depth of the PhCs, position of the quantum wells as well as the PhC period and fill factor. We review the impact of the vertical design of different approaches of PhC LEDs through a theoretical and experimental standpoint, assessing quantitatively the competing mechanisms that act over each guided mode. Three approaches are described to overcome the main limitation of LEDs with surface PhCs, i.e. the insufficient interaction of low order guided modes with the PhCs. The introduction of an AlGaN confining layer in such structure is shown to be effective in extracting a fraction of the optical energy of low order modes; however, this approach is limited by the growth of the lattice mismatched AlGaN layer on GaN. The second approach, based on thin-film LEDs with PhCs, is limited by the presence of an absorbing reflective metal layer close to the guided modes that plays a major role in the competition between PhC extraction and metal dissipation. Finally, we demonstrate both experimentally and theoretically the superior extraction of the guided light in embedded PhC LEDs due to the higher interaction between all optical modes and the PhCs, which resulted in a close to unity extraction efficiency for this device. The use of high-resolution angle-resolved measurements to experimentally determine the PhC extraction parameters was an essential tool for corroborating the theoretical models and quantifying the competing absorption and extraction mechanisms in LEDs.

  8. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting in Leavenworth, KS

    SciTech Connect (OSTI)

    Myer, Michael; Kinzey, Bruce R.; Curry, Ku'uipo

    2011-05-06T23:59:59.000Z

    This report describes the process and results of a demonstration of solid-state lighting (SSL) technology in a commercial parking lot lighting application, under the U.S. Department of Energy (DOE) Solid-State Lighting Technology GATEWAY Demonstration Program. The parking lot is for customers and employees of a Walmart Supercenter in Leavenworth, Kansas and this installation represents the first use of the LED Parking Lot Performance Specification developed by the DOE’s Commercial Building Energy Alliance. The application is a parking lot covering more than a half million square feet, lighted primarily by light-emitting diodes (LEDs). Metal halide wall packs were installed along the building facade. This site is new construction, so the installed baseline(s) were hypothetical designs. It was acknowledged early on that deviating from Walmart’s typical design would reduce the illuminance on the site. Walmart primarily uses 1000W pulse-start metal halide (PMH) lamps. In order to provide a comparison between both typical design and a design using conventional luminaires providing a lower illuminance, a 400W PMH design was also considered. As mentioned already, the illuminance would be reduced by shifting from the PMH system to the LED system. The Illuminating Engineering Society of North America (IES) provides recommended minimum illuminance values for parking lots. All designs exceeded the recommended illuminance values in IES RP-20, some by a wider margin than others. Energy savings from installing the LED system compared to the different PMH systems varied. Compared to the 1000W PMH system, the LED system would save 63 percent of the energy. However, this corresponds to a 68 percent reduction in illuminance as well. In comparison to the 400W PMH system, the LED system would save 44 percent of the energy and provide similar minimum illuminance values at the time of relamping. The LED system cost more than either of the PMH systems when comparing initial costs. However, when the life-cycle costs from energy and maintenance were factored into the scenario, the LED system had lower costs at the end of a 10-year analysis period. The LED system had a 6.1 year payback compared to the 1000W PMH system and a 7.5 year payback versus the 400W PMH system. The costs reflect high initial cost for the LED luminaire, plus more luminaires and (subsequently) more poles for the LED system. The other major issue affecting cost effectiveness was that Leavenworth, Kansas has very low electricity costs. The melded rate for this site was $0.056 per kWh for electricity. However, if the national electricity rate of $0.1022/kWh was used the payback would change to between four and five years for the LED system. This demonstration met the GATEWAY requirements of saving energy, matching or improving illumination, and being cost effective. The project also demonstrated that the Commercial Building Energy Alliance (CBEA) specification works in practice. Walmart appreciated having an entire site lighted by LEDs to gain more experience with the technology. Walmart is reviewing the results of the demonstration as they consider their entire real estate portfolio.

  9. Lumen Maintenance and Light Loss Factors: Consequences of Current Design Practices for LED's

    SciTech Connect (OSTI)

    Royer, Michael P.

    2013-09-17T23:59:59.000Z

    Synopsis: Light loss factors are used to help lighting systems meet quantitative design criteria throughout the life of the installation, but they also influence energy use. As the light sources currently being specified continue to evolve, it is necessary to reevaluate the methods used in calculating light loss factors, as well as carefully consider the consequences of different product performance attributes. Because of the unique operating characteristics of LEDs and lack of a comprehensive lifetime rating—as well as the problematic relationship between lifetime and lumen maintenance—determining an appropriate lamp lumen depreciation (LLD) factor for LED products is difficult. As a result, a unique solution has been advocated: when quantity of light is an important design consideration, the IES recommends using an LLD of not greater than 0.70. This method deviates from the typical practice for conventional sources of using the ratio of mean to initial lumen output, and can misrepresent actual performance, increase energy use, and inhibit comparisons between products. This paper discusses the complications related to LLD and LEDs, compares the performance of conventional and LED products, and examines alternatives to a maximum LLD of 0.70 for LEDs.

  10. LEDS Global Partnership in Action: Advancing Climate-Resilient Low Emission Development Around the World (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-11-01T23:59:59.000Z

    Many countries around the globe are designing and implementing low emission development strategies (LEDS). These LEDS seek to achieve social, economic, and environmental development goals while reducing long-term greenhouse gas (GHG) emissions and increasing resiliency to climate change impacts. The LEDS Global Partnership (LEDS GP) harnesses the collective knowledge and resources of more than 120 countries and international donor and technical organizations to strengthen climate-resilient low emission development efforts around the world.

  11. LED Light Fixture Project FC1 Director's Conference Room: Life Cycle Cost and Break-even Analysis

    E-Print Network [OSTI]

    Johnston, Daniel

    . A light-emitting diode (LED) is a solid-state lighting source that switches on instantly, is readily

  12. Use Patterns of LED Flashlights in Kenya and a One-Year Cost Analysis of Flashlight Ownership

    E-Print Network [OSTI]

    Tracy, Jennifer

    2010-01-01T23:59:59.000Z

    rechargeable sealed-lead acid (SLA) batteries are alsolead-acid (SLA) battery, LED flashlights powered by dry cell batteries,

  13. Low-Cost Substrates for High-Performance Nanorod Array LEDs

    SciTech Connect (OSTI)

    Sands, Timothy; Stach, Eric; Garcia, Edwin

    2009-04-30T23:59:59.000Z

    The completed project, entitled â??Low-Cost Substrates for High-Performance Nanorod LEDs,â?ť targeted the goal of a phosphor-free nanorod-based white LED with IQE > 50% across the spectrum from 450 nm to 600 nm on metallized silicon substrates. The principal achievements of this project included: â?˘ Demonstration of (In,Ga)N nanopyramid heterostructures by a conventional OMVPE process. â?˘ Verification of complete filtering of threading dislocations to yield dislocation-free pyramidal heterostructures. â?˘ Demonstration of electroluminescence with a peak wavelength of ~600 nm from an (In,Ga)N nanopyramid array LED. â?˘ Development of a reflective ZrN/AlN buffer layer for epitaxial growth of GaN films and GaN nanopyramid arrays on (111)Si.

  14. Characterization of failure modes in deep UV and deep green LEDs utilizing advanced semiconductor localization techniques.

    SciTech Connect (OSTI)

    Tangyunyong, Paiboon; Miller, Mary A.; Cole, Edward Isaac, Jr.

    2012-03-01T23:59:59.000Z

    We present the results of a two-year early career LDRD that focused on defect localization in deep green and deep ultraviolet (UV) light-emitting diodes (LEDs). We describe the laser-based techniques (TIVA/LIVA) used to localize the defects and interpret data acquired. We also describe a defect screening method based on a quick electrical measurement to determine whether defects should be present in the LEDs. We then describe the stress conditions that caused the devices to fail and how the TIVA/LIVA techniques were used to monitor the defect signals as the devices degraded and failed. We also describe the correlation between the initial defects and final degraded or failed state of the devices. Finally we show characterization results of the devices in the failed conditions and present preliminary theories as to why the devices failed for both the InGaN (green) and AlGaN (UV) LEDs.

  15. Development of Advanced Manufacturing Methods for Warm White LEDs for General Lighting

    SciTech Connect (OSTI)

    Deshpande, Anirudha; Kolodin, Boris; Jacob, Cherian; Chowdhury, Ashfaqul; Kuenzler, Glenn; Sater, Karen; Aesram, Danny; Glaettli, Steven; Gallagher, Brian; Langer, Paul; Setlur, Anant; Beers, Bill

    2012-03-31T23:59:59.000Z

    GE Lighting Solutions will develop precise and efficient manufacturing techniques for the “remote phosphor” platform of warm-white LED products. In volume, this will be demonstrated to drive significant materials, labor and capital productivity to achieve a maximum possible 53% reduction in overall cost. In addition, the typical total color variation for these white LEDs in production will be well within the ANSI bins and as low as a 4-step MacAdam ellipse centered on the black body curve. Achievement of both of these objectives will be demonstrated while meeting a performance target of > 75 lm/W for a warm-white LED and a reliability target of <30% lumen drop / <2-step MacAdam ellipse shift, estimated over 50,000 hrs.

  16. Epitaxial Growth of GaN-based LEDs on Simple Sacrificial Substrates

    SciTech Connect (OSTI)

    Ian Ferguson; Chris Summers

    2009-12-31T23:59:59.000Z

    The objective of this project is to produce alternative substrate technologies for GaN-based LEDs by developing an ALD interlayer of Al{sub 2}O{sub 3} on sacrificial substrates such as ZnO and Si. A sacrificial substrate is used for device growth that can easily be removed using a wet chemical etchant leaving only the thin GaN epi-layer. After substrate removal, the GaN LED chip can then be mounted in several different ways to a metal heat sink/reflector and light extraction techniques can then be applied to the chip and compared for performance. Success in this work will lead to high efficiency LED devices with a simple low cost fabrication method and high product yield as stated by DOE goals for its solid state lighting portfolio.

  17. LED-Induced Fluorescence System for Tea Classification and Quality Assessment

    E-Print Network [OSTI]

    Dong, Yongjiang; Mei, Liang; Feng, Chao; Yan, Chunsheng; He, Sailing

    2013-01-01T23:59:59.000Z

    A fluorescence system is developed by using several light emitting diodes (LEDs) with different wavelengths as excitation light sources. The fluorescence detection head consists of multi LED light sources and a multimode fiber for fluorescence collection, where the LEDs and the corresponding filters can be easily chosen to get appropriate excitation wavelengths for different applications. By analyzing fluorescence spectra with the principal component analysis method, the system is utilized in the classification of four types of green tea beverages and two types of black tea beverages. Qualities of the Xihu Longjing tea leaves of different grades, as well as the corresponding liquid tea samples, are studied to further investigate the ability and application of the system in the evaluation of classification/quality of tea and other foods.

  18. Lattice-mismatched GaInP LED devices and methods of fabricating same

    DOE Patents [OSTI]

    Mascarenhas, Angelo; Steiner, Myles A; Bhusal, Lekhnath; Zhang, Yong

    2014-10-21T23:59:59.000Z

    A method (100) of fabricating an LED or the active regions of an LED and an LED (200). The method includes growing, depositing or otherwise providing a bottom cladding layer (208) of a selected semiconductor alloy with an adjusted bandgap provided by intentionally disordering the structure of the cladding layer (208). A first active layer (202) may be grown above the bottom cladding layer (208) wherein the first active layer (202) is fabricated of the same semiconductor alloy, with however, a partially ordered structure. The first active layer (202) will also be fabricated to include a selected n or p type doping. The method further includes growing a second active layer (204) above the first active layer (202) where the second active layer (204) Is fabricated from the same semiconductor alloy.

  19. LEDS-An overview of the state of the art in technology and application

    SciTech Connect (OSTI)

    Johnson, Stephen

    2002-03-01T23:59:59.000Z

    Solid state lighting in the form of Light Emitting Diodes (LEDs) is bringing new sources with different operating characteristics to the market. With the control in dimension, optics, intensity and color, these sources have the potential to transform the way we use light. This paper will review the recent improvements in performance that have been achieved by these devices, focusing on those product attributes identified as being critical to end users. The paper will conclude with a consideration of applications capitalizing on the LEDs' unique operating and physical properties.

  20. Mixed Mode Matrix Multiplication

    SciTech Connect (OSTI)

    Meng-Shiou Wu; Srinivas Aluru; Ricky A. Kendall

    2004-09-30T23:59:59.000Z

    In modern clustering environments where the memory hierarchy has many layers (distributed memory, shared memory layer, cache,...), an important question is how to fully utilize all available resources and identify the most dominant layer in certain computations. When combining algorithms on all layers together, what would be the best method to get the best performance out of all the resources we have? Mixed mode programming model that uses thread programming on the shared memory layer and message passing programming on the distributed memory layer is a method that many researchers are using to utilize the memory resources. In this paper, they take an algorithmic approach that uses matrix multiplication as a tool to show how cache algorithms affect the performance of both shared memory and distributed memory algorithms. They show that with good underlying cache algorithm, overall performance is stable. When underlying cache algorithm is bad, superlinear speedup may occur, and an increasing number of threads may also improve performance.

  1. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    Electricity suppliers and electricity companies must also provide a fuel mix report to customers twice annually, within the June and December billing cycles. Emissions information must be disclos...

  2. Optimal broadcasting of mixed states

    SciTech Connect (OSTI)

    Dang Guifang; Fan Heng [Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China)

    2007-08-15T23:59:59.000Z

    The N to M (M{>=}N) universal quantum broadcasting of mixed states {rho}{sup xN} is proposed for a qubit system. The broadcasting of mixed states is universal and optimal in the sense that the shrinking factor is independent of the input state and achieves the upper bound. The quantum broadcasting of mixed qubits is a generalization of the universal quantum cloning machine for identical pure input states. A pure state decomposition of the identical mixed qubits {rho}{sup xN} is obtained.

  3. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    Maryland’s 1999 electric utility restructuring legislation requires all electric companies and electricity suppliers to provide customers with details regarding the fuel mix and emissions of...

  4. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    Ohio's 1999 electric industry restructuring law requires the state's electricity suppliers to disclose details regarding their fuel mix and emissions to customers. Electric utilities and...

  5. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    Virginia’s 1999 electric industry restructuring law requires the state's electricity providers to disclose -- "to the extent feasible" -- fuel mix and emissions data regarding electric generation....

  6. Optimal operation of a mixed fluid cascade LNG process

    E-Print Network [OSTI]

    Skogestad, Sigurd

    Optimal operation of a mixed fluid cascade LNG process Jřrgen Bauck Jensen & Sigurd Skogestad distances is to first produce liquefied natural gas (LNG) and then transport the LNG by ships. At atmospheric pressure LNG has approximately 600 times the density of gaseous NG and a temperature of ap

  7. Overview of Neutrino Mixing Models and Their Mixing Angle Predictions

    SciTech Connect (OSTI)

    Albright, Carl H.

    2009-11-01T23:59:59.000Z

    An overview of neutrino-mixing models is presented with emphasis on the types of horizontal flavor and vertical family symmetries that have been invoked. Distributions for the mixing angles of many models are displayed. Ways to differentiate among the models and to narrow the list of viable models are discussed.

  8. Measurements of moisture suction in hot mix asphalt mixes

    E-Print Network [OSTI]

    Kassem, Emad Abdel-Rahman

    2006-10-30T23:59:59.000Z

    The presence of moisture in hot mix asphalt (HMA) causes loss of strength and durability of the mix, which is referred to as moisture damage. This study deals with the development of experimental methods for measuring total suction in HMA, which can...

  9. Chip-Scale Power Conversion for LED Lighting: Integrated Power Chip Converter for Solid-State Lighting

    SciTech Connect (OSTI)

    None

    2010-10-01T23:59:59.000Z

    ADEPT Project: Teledyne is developing cost-effective power drivers for energy-efficient LED lights that fit on a compact chip. These power drivers are important because they transmit power throughout the LED device. Traditional LED driver components waste energy and don't last as long as the LED itself. They are also large and bulky, so they must be assembled onto a circuit board separately which increases the overall manufacturing cost of the LED light. Teledyne is shrinking the size and improving the efficiency of its LED driver components by using thin layers of an iron magnetic alloy and new gallium nitride on silicon devices. Smaller, more efficient components will enable the drivers to be integrated on a single chip, reducing costs. The new semiconductors in Teledyne's drivers can also handle higher levels of power and last longer without sacrificing efficiency. Initial applications for Teledyne's LED power drivers include refrigerated grocery display cases and retail lighting.

  10. Influence of coarse aggregate size, shape and surface texture on rutting of hot mix asphalt concrete

    E-Print Network [OSTI]

    Yeggoni, Mohan

    1993-01-01T23:59:59.000Z

    increased Hveem Stability, Marshall Stability and resistance to creep of hot mix asphalt concrete. The resilient modulus of the specimens was also enhanced by the increase in the amount of crushed aggregate in the mix at high temperatures (115'F). Fractal...

  11. MEASURED AND SIMULATED SF6 MIXING BEHAVIOUR R BINI, N T BASSE AND M SEEGER

    E-Print Network [OSTI]

    Basse, Nils Plesner

    distribution of the gas during the post-arc phase. Understanding the details of the mixing process occurring to investigate the turbulent mixing of the hot gas coming from an arc inside a small volume. We successfully.seeger@ch.abb.com ABSTRACT The dielectric performance of SF6 high voltage gas circuit breakers depends on the temperature

  12. SHEAR LAYER INSTABILITY AND MIXING IN MICRO HEAT SPREADERS C. Sert and A. Beskok

    E-Print Network [OSTI]

    Beskok, Ali

    SHEAR LAYER INSTABILITY AND MIXING IN MICRO HEAT SPREADERS C. Sert and A. Beskok Texas A the chip surface temperature by oscillatory flow forced convection and mixing. Numerical simulations are performed for an MHS device with channel to reservoir expansion ratio H/h 25. The boundary conditions

  13. FIELD PERFORMANCE AND LABORATORY EVALUATION OF WARM MIX ASPHALT PRODUCED WITH RUBBERIZED BITUMEN

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    FIELD PERFORMANCE AND LABORATORY EVALUATION OF WARM MIX ASPHALT PRODUCED WITH RUBBERIZED BITUMEN of rubberized bitumen has been spread out mainly due to environmental aspects, but high mixing and compaction temperatures are necessary due to the higher viscosity of this bitumen. A WMA mixture (using a surfactant

  14. Asia-Pacific Trade Economists' Conference Trade-Led Growth in Times of Crisis

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Asia-Pacific Trade Economists' Conference Trade-Led Growth in Times of Crisis The World Trade session 2: The Crisis: A Catalyst for More Coherent Trade Policies and Inclusive Growth? Author: Patrick A or carrying the endorsement of the United Nations. #12;1 Policy Brief October 26, 2009 The World Trade Regime

  15. 1 Introduction The development of wind energy use has led to

    E-Print Network [OSTI]

    Heinemann, Detlev

    1 Introduction The development of wind energy use has led to a noticeable contribution in of electricity by wind energy acts as a negative load leading to an increase in fluctuations of net load patterns conventional reserves have to be kept ready to replace the wind energy share in case of decreasing wind speeds

  16. Depth of cure and compressive strength of dental composites cured with blue light emitting diodes (LEDs)

    E-Print Network [OSTI]

    Ashworth, Stephen H.

    Depth of cure and compressive strength of dental composites cured with blue light emitting diodes with either a light emitting diode (LED) based light curing unit (LCU) or a conventional halogen LCU do reserved. Keywords: Blue light emitting diodes; Light curing unit; Composites; Irradiance; Spectrum; Depth

  17. Coupled optical and electronic simulations of electrically pumped photonic-crystal-based LEDs

    E-Print Network [OSTI]

    Dutton, Robert W.

    to investigate design tradeoffs in electrically pumped photonic crystal light emitting diodes. A finite. Keywords: Photonic crystal light emitting diode, electrically pumped device 1. INTRODUCTION Recently optoelectronic devices, such as light emitting diodes (LEDs) and lasers. It has been suggested that a thin slab

  18. Ruofan Wu, Hieu Pham Trung Nguyen and Zetian Mi INTRODUCTION TO LEDs

    E-Print Network [OSTI]

    Barthelat, Francois

    -in-a-Wire Light Emitting Diodes and Prevention Method Nano-electronic Devices and Materials, Electrical Computer., Efficiency droop in nitride-based light-emitting diodes. Physica Status Solidi a-Applications and Materials history. Nature Photonics 2007, 1 (4), 189-192. [4] Holonyak, N., Is the light emitting diode (LED

  19. DOE Publishes CALiPER Report on Linear (T8) LED Lamps in Recessed Troffers

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released Report 21.2, which is part of a series of investigations on linear LED lamps. Report 21.2 focuses on the performance of three linear (T8...

  20. DOE Publishes CALiPER Report on Cost-Effectiveness of Linear (T8) LED Lamps

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released Report 21.3, which is part of a series of investigations on linear LED lamps. Report 21.3 details a set of life-cycle cost simulations...

  1. forestry.gov.uk/carboncode The Woodland Carbon Code is an initiative led by the

    E-Print Network [OSTI]

    carbon from these projects brings many benefits in addition to carbon sequestration. is effectivelyforestry.gov.uk/carboncode ® The Woodland Carbon Code is an initiative led by the Forestry Commission and supported by a Carbon Advisory Group of UK forest industry and carbon market experts. A buyers

  2. Office of International Programs Education Abroad CSU Faculty-Led Programs Support

    E-Print Network [OSTI]

    Office of International Programs ­ Education Abroad 12/2012 CSU Faculty-Led Programs Support Below describes the levels of support and ways that the Office of International Programs ­ Education Abroad unit in the field of international education Application and Maintain website and online application system

  3. High-power LEDs based on InGaAsP/InP heterostructures

    SciTech Connect (OSTI)

    Rakovics, V. [Hungarian Academy of Sciences, Institute of Technical Physics and Materials Science, Research Centre for Natural Sciences (Hungary); Imenkov, A. N.; Sherstnev, V. V.; Serebrennikova, O. Yu.; Il’inskaya, N. D.; Yakovlev, Yu. P., E-mail: Yak@iropt1.ioffe.ru [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

    2014-12-15T23:59:59.000Z

    High-power light-emitting diodes (LEDs) with mesa diameters of 100, 200, and 300 ?m are developed on the basis of InGaAsP/InP heterostructures. The mesas are close in shape to a truncated cone with a generatrix inclination angle of ?45° in the vicinity of the active region of the LED, with a ring etched around the mesa serving as a reflector. The emission spectra and directivity patterns of these LEDs are studied in a wide range of current densities and it is shown that radiative recombination is dominant to a current density of ?5000 A/cm{sup 2}, which makes these structures promising for the development of high-power LEDs. An emission power of ?14 mW is obtained in the continuous-wave mode (I = 0.2 A, ? = 1.1 ?m), and that of 77 mW, in the pulsed mode (I = 2 A, ? = 1.1 ?m), which corresponds to external quantum efficiencies of 6.2 and 3.4%, respectively.

  4. General practitioner-led commissioning in the NHS: progress, prospects and pitfalls

    E-Print Network [OSTI]

    Birmingham, University of

    General practitioner-led commissioning in the NHS: progress, prospects and pitfalls Russell Mannion of general practitioner (GP) consortia. These organisations will have responsibility for commissioning on impact of the previous models of GP commissioning that have been introduced in the NHS with the aim

  5. Calibration of Cangaroo II Telescope Using a Fast Blue LED Light Flasher

    E-Print Network [OSTI]

    Enomoto, Ryoji

    , as well as test the data acquisition electronics. Our technique is an independent variation of the laser , and a risetime of #24; 1 ns. The LED has a double emitter giving a non-uniform light pool. By drilling a small

  6. Philips' LED Luminaires Brighten the Rensselaer Engineering Fabrication & Prototyping Facility (also known as the Machine Shop)

    E-Print Network [OSTI]

    Linhardt, Robert J.

    . #12;To help bridge its research efforts with currently available solid state lighting technology outreach to increase campus and community awareness as to the benefits of solid state lighting. About Royal a donation of LED fixtures from Philips Lighting. The Smart Lighting Sustainability Club, comprised

  7. December 2014 CCE-Led One-Time Service Projects Transportation Provided

    E-Print Network [OSTI]

    Collins, Gary S.

    December 2014 CCE-Led One-Time Service Projects Transportation Provided Check In Times Listed Place Senior Center Manicures 6 PM ­ 8 PM 4 Colton Pen Friends 8:15 AM ­ 11:30 AM Recycling Outreach Friends 8:15 AM ­ 11:30 AM Recycling Outreach Campus to Community 10 AM ­ 1 PM Whitman Senior Living

  8. Mercury Releases to Air and Rivers Contaminate Ocean Fish: Dartmouth-Led Effort Publishes Major Findings

    E-Print Network [OSTI]

    Myers, Lawrence C.

    Mercury Releases to Air and Rivers Contaminate Ocean Fish: Dartmouth-Led Effort Publishes Major and in Sources to Seafood: Mercury Pollution in the Marine Environment-- a companion report by the Dartmouth released into the air and then deposited into oceans, contaminates seafood commonly eaten by people

  9. Crystal coat warms up LED light 16:46 01 February 2008

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    in the commercial market. Illuminating buildings accounts for about a quarter of the electricity used in the US in the home. Now researchers have used nanocrystals to create LEDs that give off a warm white light. Fine Articles 'Smart' lamp offers true mood lighting http://technology.newscientist.com/article/mg19626276

  10. Phosphors for near UV-Emitting LED's for Efficacious Generation of White Light

    SciTech Connect (OSTI)

    McKittrick, Joanna

    2013-09-30T23:59:59.000Z

    1) We studied phosphors for near-UV (nUV) LED application as an alternative to blue LEDs currently being used in SSL systems. We have shown that nUV light sources could be very efficient at high current and will have significantly less binning at both the chip and phosphor levels. We identified phosphor blends that could yield 4100K lamps with a CRI of approximately 80 and LPWnUV,opt equal to 179 for the best performing phosphor blend. Considering the fact that the lamps were not optimized for light coupling, the results are quite impressive. The main bottleneck is an optimum blue phosphor with a peak near 440 nm with a full width half maximum of about 25 nm and a quantum efficiency of >95%. Unfortunately, that may be a very difficult task when we want to excite a phosphor at ~400 nm with a very small margin for Stokes shift. Another way is to have all the phosphors in the blend having the excitation peak at 400 nm or slightly shorter wavelength. This could lead to a white light source with no body color and optimum efficacy due to no self-absorption effects by phosphors in the blend. This is even harder than finding an ideal blue phosphor, but not necessarily impossible. 2) With the phosphor blends identified, light sources using nUV LEDs at high current could be designed with comparable efficacy to those using blue LEDs. It will allow us to design light sources with multiple wattages using the same chips and phosphor blends simply by varying the input current. In the case of blue LEDs, this is not currently possible because varying the current will lower the efficacy at high current and alter the color point. With improvement of phosphor blends, control over CRI could improve. Less binning at the chip level and also at the phosphor blend level could reduce the cost of SSL light sources. 3) This study provided a deeper understanding of phosphor characteristics needed for LEDs in general and nUV LEDs in particular. Two students received Ph.D. degrees and three undergraduates participated in this work. Two of the undergraduate students are now in graduate school. The results were widely disseminated – 20 archival journal publications (published, accepted or in preparation) and three conference proceedings resulted. The students presented their work at 11 different national/international conferences (32 oral or poster presentations) and the PI’s delivered 12 invited, keynote or plenary lectures.

  11. High temperature Seebeck coefficient metrology

    SciTech Connect (OSTI)

    Martin, J. [Materials Science and Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Tritt, T. [Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634 (United States); Uher, C. [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2010-12-15T23:59:59.000Z

    We present an overview of the challenges and practices of thermoelectric metrology on bulk materials at high temperature (300 to 1300 K). The Seebeck coefficient, when combined with thermal and electrical conductivity, is an essential property measurement for evaluating the potential performance of novel thermoelectric materials. However, there is some question as to which measurement technique(s) provides the most accurate determination of the Seebeck coefficient at high temperature. This has led to the implementation of nonideal practices that have further complicated the confirmation of reported high ZT materials. To ensure meaningful interlaboratory comparison of data, thermoelectric measurements must be reliable, accurate, and consistent. This article will summarize and compare the relevant measurement techniques and apparatus designs required to effectively manage uncertainty, while also providing a reference resource of previous advances in high temperature thermoelectric metrology.

  12. High temperature Seebeck coefficient metrology

    SciTech Connect (OSTI)

    Martin, J.; Tritt, T.; Uher, Ctirad

    2010-01-01T23:59:59.000Z

    We present an overview of the challenges and practices of thermoelectric metrology on bulk materials at high temperature (300 to 1300 K). The Seebeck coefficient, when combined with thermal and electrical conductivity, is an essential propertymeasurement for evaluating the potential performance of novel thermoelectricmaterials. However, there is some question as to which measurement technique(s) provides the most accurate determination of the Seebeck coefficient at high temperature. This has led to the implementation of nonideal practices that have further complicated the confirmation of reported high ZT materials. To ensure meaningful interlaboratory comparison of data, thermoelectricmeasurements must be reliable, accurate, and consistent. This article will summarize and compare the relevant measurement techniques and apparatus designs required to effectively manage uncertainty, while also providing a reference resource of previous advances in high temperature thermoelectric metrology.

  13. Sequential high temperature reduction, low temperature hydrolysis...

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

    high temperature reduction, low temperature hydrolysis for the regeneration of sulfated NOx trap catalysts. Sequential high temperature reduction, low temperature hydrolysis for...

  14. The temperature sensitivity of a bistable RAM

    E-Print Network [OSTI]

    Brown, Janet Kay

    1986-01-01T23:59:59.000Z

    is applied to the polycrystalline-silicon resistor of a new bistable RAM cell. The effect of temperature on the resistor is explored with respect to the operation of the RAM cell's refresh mechanism. A temperature range of 0 ? 100'C is investigated... of user defined function, DER 16. TB, fpiy verses doping concentration 17. TB, f ty verses temperature range Page 16 17 26 27' 28 29 30 CHAPTER I INTRODUCTION The search for small, dense memories has led to the dynamic RAM cell which...

  15. Neutrino Mixing and Discrete Symmetries

    E-Print Network [OSTI]

    Hu, Bo

    2012-01-01T23:59:59.000Z

    A model independent study of neutrino mixing based on a new method to derive mixing patterns is presented. An interesting result we find is that, in the case where unbroken residual symmetries of the Majorana neutrino and left-handed charged-lepton mass matrices obey some general assumptions, the complete set of possible mixing patterns can be determined by the solutions to the constraint equation with the help of algebraic number theory. This method can also be applied to more general cases beyond the minimal scenario. Several applications and phenomenological implications are discussed.

  16. Massive zero-metal stars: Energy production and mixing

    E-Print Network [OSTI]

    C. W. Straka; W. M. Tscharnuter

    2001-03-21T23:59:59.000Z

    Time-dependent nuclear network calculations at constant temperature show that for zero-metal stars >= 20 Msun (i) beta-decay reactions and (ii) the 13N(p,gamma)14O reaction must be included. It is also shown that the nuclear timescale in these zero-metal stars is shorter than the mixing timescale and therefore the assumption of instantaneous mixing across convective regions is not fulfilled. We conclude that proper modeling of these processes may alter the evolution of massive zero-metal stars.

  17. Optical and electrical studies of cerium mixed oxides

    SciTech Connect (OSTI)

    Sherly, T. R., E-mail: trsherly@gmail.com [Post Graduate Department of Physics, Sanathana Dharma College, Alappuzha, Kerala (India); Raveendran, R. [Nanoscience Research Laboratory, Sree Narayana College, Kollam, Kerala 691001 (India)

    2014-10-15T23:59:59.000Z

    The fast development in nanotechnology makes enthusiastic interest in developing nanomaterials having tailor made properties. Cerium mixed oxide materials have received great attention due to their UV absorption property, high reactivity, stability at high temperature, good electrical property etc and these materials find wide applications in solid oxide fuel cells, solar control films, cosmetics, display units, gas sensors etc. In this study cerium mixed oxide compounds were prepared by co-precipitation method. All the samples were doped with Zn (II) and Fe (II). Preliminary characterizations such as XRD, SEM / EDS, TEM were done. UV - Vis, Diffuse reflectance, PL, FT-IR, Raman and ac conductivity studies of the samples were performed.

  18. LED lamp or bulb with remote phosphor and diffuser configuration with enhanced scattering properties

    DOE Patents [OSTI]

    Tong, Tao; Le Toquin, Ronan; Keller, Bernd; Tarsa, Eric; Youmans, Mark; Lowes, Theodore; Medendorp, Jr., Nicholas W; Van De Ven, Antony; Negley, Gerald

    2014-11-11T23:59:59.000Z

    An LED lamp or bulb is disclosed that comprises a light source, a heat sink structure and an optical cavity. The optical cavity comprises a phosphor carrier having a conversions material and arranged over an opening to the cavity. The phosphor carrier comprises a thermally conductive transparent material and is thermally coupled to the heat sink structure. An LED based light source is mounted in the optical cavity remote to the phosphor carrier with light from the light source passing through the phosphor carrier. A diffuser dome is included that is mounted over the optical cavity, with light from the optical cavity passing through the diffuser dome. The properties of the diffuser, such as geometry, scattering properties of the scattering layer, surface roughness or smoothness, and spatial distribution of the scattering layer properties may be used to control various lamp properties such as color uniformity and light intensity distribution as a function of viewing angle.

  19. A portable time-domain LED fluorimeter for nanosecond fluorescence lifetime measurements

    SciTech Connect (OSTI)

    Wang, Hongtao; Salthouse, Christopher D., E-mail: salthouse@ecs.umass.edu [Electrical and Computer Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Qi, Ying; Mountziaris, T. J. [Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States) [Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Chemical Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States)

    2014-05-15T23:59:59.000Z

    Fluorescence lifetime measurements are becoming increasingly important in chemical and biological research. Time-domain lifetime measurements offer fluorescence multiplexing and improved handling of interferers compared with the frequency-domain technique. In this paper, an all solid-state, filterless, and highly portable light-emitting-diode based time-domain fluorimeter (LED TDF) is reported for the measurement of nanosecond fluorescence lifetimes. LED based excitation provides more wavelengths options compared to laser diode based excitation, but the excitation is less effective due to the uncollimated beam, less optical power, and longer latency in state transition. Pulse triggering and pre-bias techniques were implemented in our LED TDF to improve the peak optical power to over 100 mW. The proposed pulsing circuit achieved an excitation light fall time of less than 2 ns. Electrical resetting technique realized a time-gated photo-detector to remove the interference of the excitation light with fluorescence. These techniques allow the LED fluorimeter to accurately measure the fluorescence lifetime of fluorescein down to concentration of 0.5 ?M. In addition, all filters required in traditional instruments are eliminated for the non-attenuated excitation/emission light power. These achievements make the reported device attractive to biochemical laboratories seeking for highly portable lifetime detection devices for developing sensors based on fluorescence lifetime changes. The device was initially validated by measuring the lifetimes of three commercial fluorophores and comparing them with reported lifetime data. It was subsequently used to characterize a ZnSe quantum dot based DNA sensor.

  20. Observed Minimum Illuminance Threshold for Night Market Vendors in Kenya who use LED Lamps

    SciTech Connect (OSTI)

    Johnstone, Peter; Jacobson, Arne; Mills, Evan; Radecsky, Kristen

    2009-03-21T23:59:59.000Z

    Creation of light for work, socializing, and general illumination is a fundamental application of technology around the world. For those who lack access to electricity, an emerging and diverse range of LED based lighting products hold promise for replacing and/or augmenting their current fuel-based lighting sources that are costly and dirty. Along with analysis of environmental factors, economic models for total cost-ofownership of LED lighting products are an important tool for studying the impacts of these products as they emerge in markets of developing countries. One important metric in those models is the minimum illuminance demanded by end-users for a given task before recharging the lamp or replacing batteries. It impacts the lighting service cost per unit time if charging is done with purchased electricity, batteries, or charging services. The concept is illustrated in figure 1: LED lighting products are generally brightest immediately after the battery is charged or replaced and the illuminance degrades as the battery is discharged. When a minimum threshold level of illuminance is reached, the operational time for the battery charge cycle is over. The cost to recharge depends on the method utilized; these include charging at a shop at a fixed price per charge, charging on personal grid connections, using solar chargers, and purchasing dry cell batteries. This Research Note reports on the observed"charge-triggering" illuminance level threshold for night market vendors who use LED lighting products to provide general and task oriented illumination. All the study participants charged with AC power, either at a fixed-price charge shop or with electricity at their home.

  1. Aspen Ecology in the MixedAspen Ecology in the Mixed Conifer TypeConifer Type

    E-Print Network [OSTI]

    Aspen Ecology in the MixedAspen Ecology in the Mixed Conifer TypeConifer Type Wayne D. Shepperd Colorado State University Fort Collins, CO Aspen Ecology in the MixedAspen Ecology in the Mixed Conifer disturbances to meet the desired objective #12;Aspen in Mixed Conifer ForestsAspen in Mixed Conifer Forests

  2. CALiPER Report 20.3: Robustness of LED PAR38 Lamps

    SciTech Connect (OSTI)

    Poplawski, Michael E.; Royer, Michael P.; Brown, Charles C.

    2014-12-31T23:59:59.000Z

    Three samples of 40 of the Series 20 PAR38 lamps underwent multi-stress testing, whereby samples were subjected to increasing levels of simultaneous thermal, humidity, electrical, and vibrational stress. The results do not explicitly predict expected lifetime or reliability, but they can be compared with one another, as well as with benchmark conventional products, to assess the relative robustness of the product designs. On average, the 32 LED lamp models tested were substantially more robust than the conventional benchmark lamps. As with other performance attributes, however, there was great variability in the robustness and design maturity of the LED lamps. Several LED lamp samples failed within the first one or two levels of the ten-level stress plan, while all three samples of some lamp models completed all ten levels. One potential area of improvement is design maturity, given that more than 25% of the lamp models demonstrated a difference in failure level for the three samples that was greater than or equal to the maximum for the benchmarks. At the same time, the fact that nearly 75% of the lamp models exhibited better design maturity than the benchmarks is noteworthy, given the relative stage of development for the technology.

  3. Self-reported Impacts of LED Lighting Technology Compared to Fuel-based Lighting on Night Market Business Prosperity in Kenya

    E-Print Network [OSTI]

    Johnstone, Peter

    2009-01-01T23:59:59.000Z

    s kiosk illuminated by her LED lamp [1/2009] “A.N. ” Market:charge at a shop) “The [LED] lamp is very important and mylamp, hurricane lamp, and LED lamp illuminate night market

  4. LED Lamp Project Lights the Way to Flicker-Free Replacement Jade Sky Technologies and UC Davis's California Lighting Technology Center demonstrate the

    E-Print Network [OSTI]

    California at Davis, University of

    LED Lamp Project Lights the Way to Flicker-Free Replacement Jade Sky the flicker and dimming requirements set by the Voluntary California Quality LED Lamp for incentivized LED replacement lamps. These criteria go beyond energy efficiency

  5. Fluid Mixing from Viscous Fingering

    E-Print Network [OSTI]

    Jha, Birendra

    Mixing efficiency at low Reynolds numbers can be enhanced by exploiting hydrodynamic instabilities that induce heterogeneity and disorder in the flow. The unstable displacement of fluids with different viscosities, or ...

  6. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    Rhode Island requires all entities that sell electricity in the state to disclose details regarding the fuel mix and emissions of their electric generation to end-use customers. This information...

  7. Mixed-mu superconducting bearings

    DOE Patents [OSTI]

    Hull, J.R.; Mulcahy, T.M.

    1998-03-03T23:59:59.000Z

    A mixed-mu superconducting bearing is disclosed including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure. 9 figs.

  8. Mixed-mu superconducting bearings

    DOE Patents [OSTI]

    Hull, John R. (Hinsdale, IL); Mulcahy, Thomas M. (Western Springs, IL)

    1998-01-01T23:59:59.000Z

    A mixed-mu superconducting bearing including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure.

  9. Is the tribimaximal mixing accidental?

    SciTech Connect (OSTI)

    Abbas, Mohammed [Ain Shams University, Faculty of Sciences, Abbassiyah 11566, Cairo (Egypt); Center for Theoretical Physics (CTP), British University in Egypt, BUE, El-Sherouk City, Cairo (Egypt); Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, I-34014 Trieste (Italy); Smirnov, A. Yu. [Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, I-34014 Trieste (Italy); Institute for Nuclear Research, Russian Academy of Sciences, Moscow (Russian Federation)

    2010-07-01T23:59:59.000Z

    The tribimaximal (TBM) mixing is not accidental if structures of the corresponding leptonic mass matrices follow immediately from certain (residual or broken) flavor symmetry. We develop a simple formalism which allows one to analyze effects of deviations of the lepton mixing from TBM on the structure of the neutrino mass matrix and on the underlying flavor symmetry. We show that possible deviations from the TBM mixing can lead to strong modifications of the mass matrix and strong violation of the TBM-mass relations. As a result, the mass matrix may have an 'anarchical' structure with random values of elements or it may have some symmetry that differs from the TBM symmetry. Interesting examples include matrices with texture zeros, matrices with certain 'flavor alignment' as well as hierarchical matrices with a two-component structure, where the dominant and subdominant contributions have different symmetries. This opens up new approaches to understanding the lepton mixing.

  10. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    In 2001, Nevada enacted legislation requiring the state’s electric utilities to provide details regarding the fuel mix and emissions of electric generation to their customers. Utilities must...

  11. Fuel Mix and Emissions Disclosure

    Broader source: Energy.gov [DOE]

    Michigan's Customer Choice and Electric Reliability Act of 2000 (P.A. 141) requires electric suppliers to disclose to customers details related to the fuel mix and emissions, in pounds per megawatt...

  12. NOVEL TECHNOLOGIES DEVELOPED BY CREE LOWER THE COST OF HIGH-PERFORMANCE LED TROFFERS ON THE MARKET

    Broader source: Energy.gov [DOE]

    Cree used a comprehensive approach to reduce the costs of various optical, thermal, and electrical subsystems without impacting performance, resulting in an LED troffer luminaire platform emitting...

  13. Text-Alternative Version: LED Site Lighting in the Commercial Building Sector: Opportunities, Challenges, and the CBEA Performance Specification

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the LED Site Lighting in the Commercial Building Sector: Opportunities, Challenges, and the CBEA Performance Specification webcast.

  14. Electrophoretic Deposition of Highly Efficient Phosphors for White Solid State Lighting using near UV-Emitting LEDs /

    E-Print Network [OSTI]

    Choi, Jae Ik

    2014-01-01T23:59:59.000Z

    application in white light emitting diode,” J. Mater. Res. ,phosphors for white light emitting diodes (LEDs)”, 220 thconverted white light emitting diodes by electrophoretic

  15. Mixed-Mode Ventilation and Building Retrofits

    E-Print Network [OSTI]

    Brager, Gail; Ackerly, Katie

    2010-01-01T23:59:59.000Z

    Page 15 Mixed-Mode Ventilation and Building RetrofitsEngineers. 2000. Mixed-mode ventilation. CIBSE ApplicationsMichael. 2000. Hybrid Ventilation Systems: An Arup Approach

  16. Occupant satisfaction in mixed-mode buildings.

    E-Print Network [OSTI]

    Brager, Gail; Baker, Lindsay

    2008-01-01T23:59:59.000Z

    Strategies for Mixed-Mode Buildings, Summary Report, CenterCBE). 2006. Website: Mixed-Mode Building Case Studies.Department of Environmental Building Research Establishment

  17. Occupant satisfaction in mixed-mode buildings

    E-Print Network [OSTI]

    Brager, Gail; Baker, Lindsay

    2009-01-01T23:59:59.000Z

    Environmental Quality in Green Buildings”. Indoor Air; 14 (Strategies for Mixed-Mode Buildings, Summary Report, CenterCBE). 2006. Website: Mixed-Mode Building Case Studies.

  18. Neutrino Masses and Flavor Mixing

    E-Print Network [OSTI]

    Fritzsch, Harald

    2015-01-01T23:59:59.000Z

    We discuss the neutrino oscillations, using texture zero mass matrices for the leptons. The reactor mixing angle $\\theta^{}_{l}$ is calculated. The ratio of the masses of two neutrinos is determined by the solar mixing angle. We can calculate the masses of the three neutrinos: $m_1$ $\\approx$ 0.003 eV - $m_2$ $\\approx$ 0.012 eV - $m_3$ $\\approx$ 0.048 eV.

  19. Neutrino Masses and Flavor Mixing

    E-Print Network [OSTI]

    Harald Fritzsch

    2015-03-06T23:59:59.000Z

    We discuss the neutrino oscillations, using texture zero mass matrices for the leptons. The reactor mixing angle $\\theta^{}_{l}$ is calculated. The ratio of the masses of two neutrinos is determined by the solar mixing angle. We can calculate the masses of the three neutrinos: $m_1$ $\\approx$ 0.003 eV - $m_2$ $\\approx$ 0.012 eV - $m_3$ $\\approx$ 0.048 eV.

  20. Quantum computing with mixed states

    E-Print Network [OSTI]

    Michael Siomau; Stephan Fritzsche

    2011-01-17T23:59:59.000Z

    We discuss a model for quantum computing with initially mixed states. Although such a computer is known to be less powerful than a quantum computer operating with pure (entangled) states, it may efficiently solve some problems for which no efficient classical algorithms are known. We suggest a new implementation of quantum computation with initially mixed states in which an algorithm realization is achieved by means of optimal basis independent transformations of qubits.

  1. Quantum computing with mixed states

    E-Print Network [OSTI]

    Siomau, Michael

    2011-01-01T23:59:59.000Z

    We discuss a model for quantum computing with initially mixed states. Although such a computer is known to be less powerful than a quantum computer operating with pure (entangled) states, it may efficiently solve some problems for which no efficient classical algorithms are known. We suggest a new implementation of quantum computation with initially mixed states in which an algorithm realization is achieved by means of optimal basis independent transformations of qubits.

  2. Development of Production PVD-AIN Buffer Layer System and Processes to Reduce Epitaxy Costs and Increase LED Efficiency

    SciTech Connect (OSTI)

    Cerio, Frank

    2013-09-14T23:59:59.000Z

    The DOE has set aggressive goals for solid state lighting (SSL) adoption, which require manufacturing and quality improvements for virtually all process steps leading to an LED luminaire product. The goals pertinent to this proposed project are to reduce the cost and improve the quality of the epitaxial growth processes used to build LED structures. The objectives outlined in this proposal focus on achieving cost reduction and performance improvements over state-of-the-art, using technologies that are low in cost and amenable to high efficiency manufacturing. The objectives of the outlined proposal focus on cost reductions in epitaxial growth by reducing epitaxy layer thickness and hetero-epitaxial strain, and by enabling the use of larger, less expensive silicon substrates and would be accomplished through the introduction of a high productivity reactive sputtering system and an effective sputtered aluminum-nitride (AlN) buffer/nucleation layer process. Success of the proposed project could enable efficient adoption of GaN on-silicon (GaN/Si) epitaxial technology on 150mm silicon substrates. The reduction in epitaxy cost per cm{sup 2} using 150mm GaN-on-Si technology derives from (1) a reduction in cost of ownership and increase in throughput for the buffer deposition process via the elimination of MOCVD buffer layers and other throughput and CoO enhancements, (2) improvement in brightness through reductions in defect density, (3) reduction in substrate cost through the replacement of sapphire with silicon, and (4) reduction in non-ESD yield loss through reductions in wafer bow and temperature variation. The adoption of 150mm GaN/Si processing will also facilitate significant cost reductions in subsequent wafer fabrication manufacturing costs. There were three phases to this project. These three phases overlap in order to aggressively facilitate a commercially available production GaN/Si capability. In Phase I of the project, the repeatability of the performance was analyzed and improvements implemented to the Veeco PVD-AlN prototype system to establish a specification and baseline PVD-AlN films on sapphire and in parallel the evaluation of PVD AlN on silicon substrates began. In Phase II of the project a Beta tool based on a scaled-up process module capable of depositing uniform films on batches of 4”or 6” diameter substrates in a production worthy operation was developed and qualified. In Phase III, the means to increase the throughput of the PVD-AlN system was evaluated and focused primarily on minimizing the impact of the substrate heating and cooling times that dominated the overall cycle time.

  3. LED Traffic Light as a Communications Device Grantham Pang, Thomas Kwan, Chi-Ho Chan, Hugh Liu.

    E-Print Network [OSTI]

    Pang, Grantham

    :http://www.eee.hku.hk/~gpang Abstract The visible light from an LED (light emitting diode) traffic light can be modulated and encoded on the description of an audio information system made up of high brightness, visible light emitting diodes (LEDs messages 1. Introduction Recently, high intensity light emitting diodes for traffic signals are available

  4. Nice, Cte d'Azur, France, 27-29 September 2006 THERMAL MODELING OF HIGH POWER LED MODULES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    generation a part of the input electric power is converted into light, which is described by the wall plugNice, Côte d'Azur, France, 27-29 September 2006 THERMAL MODELING OF HIGH POWER LED MODULES D a study of accuracy issues in thermal modeling of high power LED modules on system level. Both physical

  5. Quantum efficiency enhancement in nanocrystals using nonradiative energy transfer with optimized donor-acceptor ratio for hybrid LEDs

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    Quantum efficiency enhancement in nanocrystals using nonradiative energy transfer with optimized donor-acceptor ratio for hybrid LEDs Sedat Nizamoglu, Onur Akin, and Hilmi Volkan Demira Department emitting diodes LEDs . For this purpose, we investigate energy gradient mixture of nanocrystal solids

  6. Room-temperature direct bandgap electroluminesence from Ge-on-Si light-emitting diodes

    E-Print Network [OSTI]

    Sun, Xiaochen

    We report what we believe to be the first demonstration of direct bandgap electroluminescence (EL) from Ge/Si heterojunction light-emitting diodes (LEDs) at room temperature. In-plane biaxial tensile strain is used to ...

  7. Philips Light Sources & Electronics is Developing an Efficient, Smaller, Cost-Effective Family of LED Drivers

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, Philips Light Sources & Electronics is developing a new family of LED drivers that are more efficient and cost-effective as well as smaller in size than currently available drivers. The new drivers are switch-mode power supplies that are similar to today's drivers, but with an improved design. In addition, they have a different topology—boost plus LLC—for wattages of 40W and above, but they retain the commonly used flyback topology at lower wattages.

  8. Solar LED Light Pilot Project Illuminates the Way in Alabama | Department

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33Frequently AskedEnergyIssues DOE's Nuclear EnergySmart Metersof Energy LED Light Pilot

  9. Zimbabwe-Terms of Reference for Future LEDS | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTriWildcat 1 Wind Projectsource History ViewZAP JumpZenergyZeppiniLEDS

  10. Intel Led OpenMP Training Session at NERSC This Wednesday March 25

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes | National Nuclear Security AdministrationIntegratingIntel IntelLed

  11. Unique PPPL-led workshop assesses research crucial to the success of ITER |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrinceton Plasma Physics Lab Unique PPPL-led workshop assesses

  12. Kenya-EC-LEDS in the Agriculture Sector | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOf Kilauea Volcano, Hawaii |Island,Kas Farmssource HistoryKenworthLEDS in

  13. Enhancing Capacity for Low Emission Development Strategies (EC-LEDS) | Open

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model,DOEHazel Crest,EnergySerranopolis JumpESLEnergy Information LEDS)

  14. Temperature (oC)! Height(km)!

    E-Print Network [OSTI]

    and forecasting ! ·Temperature decreases in altitude + water vapor > instabilities can develop ·Well mixed + O2 + M = O3 + M to proceed. It is M here that transfers the excess energy to the surrounding created and transported to high latitudes PSCs form in cold, dark, polar lower stratosphere PSCs process

  15. Compositional changes in red and violet smoke mixes after combustion

    SciTech Connect (OSTI)

    Buchanan, M.V.; Rubin, I.B.; Moneyhun, J.H.

    1983-01-01T23:59:59.000Z

    Anthraquinone-derived dyes are commonly used in colored dye mixes prepared for signal smoke grenades. Biological studies have shown, however, that a number of these dyes exhibit bacterial mutagenicity. In addition, these dyes are similar in structure to several polycyclic aromatic hydrocarbons which are well-known carcinogens. The grenades contain not only anthraquinone-derived dyes, but also a pyrotechnic fuel and cooling and starting mixes consisting primarily of potassium chlorate and nitrate, sodium bicarbonate, and sulfur. These dyes are volatilized at temperatures up to 550/sup 0/C during the detonation of the grenade, which could subject the dyes to oxidative and pyrolytic reactions that could result in a variety of reaction by-products. As part of a program to investigate possible environmental and occupational risks of the colored smoke dyes and in signal grenades, two colored smoke mixes, red and violet, have been studied both before and after detonation to evaluate any differences in composition due to the combustion process. This report focuses primarily on the separation and identification of the components of the original and combusted red and violet smoke mixes. The conditions for the detonation of the smoke grenades and sampling of the combusted smoke mixes are also discussed.

  16. A photometric investigation of ultra-efficient LEDs with high color rendering index and high

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    and distribution temperature," J. Opt. Soc. Am. 58(11), 1528­1535 (1968). #119158 - $15.00 USD Received 27 Oct 2009 Sun2 and Hilmi Volkan Demir1,2* 1 Department of Electrical and Electronics Engineering, Department temperature of 3000 K are shown to be achieved using nanocrystal luminophores. ©2009 Optical Society

  17. Demonstration of LED Retrofit Lamps at the Jordan Schnitzer Museum of Art

    SciTech Connect (OSTI)

    Miller, Naomi J.

    2011-09-01T23:59:59.000Z

    The Jordan Schnitzer Museum of Art in Eugene, Oregon, houses a remarkable permanent collection of Asian art and antiquities, modern art, and sculpture, and also hosts traveling exhibitions. In the winter and spring of 2011, a series of digital photographs by artist Chris Jordan, titled "Running the Numbers," was exhibited in the Coeta and Donald Barker Special Exhibitions Gallery. These works graphically illustrate waste (energy, money, health, consumer objects, etc.) in contemporary culture. The Bonneville Power Administration and the Eugene Water and Electricity Board provided a set of Cree 12W light-emitting diode (LED) PAR38 replacement lamps (Cree LRP38) for the museum to test for accent lighting in lieu of their standard Sylvania 90W PAR38 130V Narrow Flood lamps (which draw 78.9W at 120V). At the same time, the museum tested LED replacement lamps from three other manufacturers, and chose the Cree lamp as the most versatile and most appropriate color product for this exhibit. The lamps were installed for the opening of the show in January 2011. This report describes the process for the demonstration, the energy and economic results, and results of a survey of the museum staff and gallery visitors on four similar clusters of art lighted separately by four PAR38 lamps.

  18. Demonstration Assessment of Light-Emitting Diode (LED) Street Lighting Host Site: Lija Loop, Portland, Oregon

    SciTech Connect (OSTI)

    Kinzey, Bruce R.; Myer, Michael

    2009-11-01T23:59:59.000Z

    This report describes the process and results of a demonstration of solid-state lighting (SSL) technology in a residential street lighting application, under the U.S. Department of Energy GATEWAY Solid-State Lighting Technology Demonstration Program. In this project, eight 100W (nominal) high-pressure sodium cobra head fixtures were replaced with a like number of LED street light luminaires manufactured by Leotek, Inc. The Leotek product achieved an estimated payback in the Lija Loop installation of about 20 years for replacement scenarios and a much shorter 7.6 years for new installations. Much of the associated energy savings (55%) supporting these payback periods, however, were achieved by reducing average horizontal photopic illuminance a similar amount (53%). Examined from a different perspective, the measured performance suggests that the Leotek product is at approximate parity with the HPS cobra head in terms of average delivered photopic illumination for a given power consumption. HPS comprises the second most efficacious street lighting technology available, exceeded only by low pressure sodium (LPS). LPS technology is not considered suitable for most street lighting applications due to its monochromatic spectral output and poor color rendering ability; therefore, this LED product is performing at an efficiency level comparable to its primary competition in this application.

  19. Electron transport and frozen concentration gradients in a mixed valent viologen molten salt

    SciTech Connect (OSTI)

    Terrill, R.H.; Hatazawa, Tsuyonobu; Murray, R.W. [Univ. of North Carolina, Chapel Hill, NC (United States)

    1995-11-09T23:59:59.000Z

    This paper shows that electrolytically generated crossed concentration gradients of viologen (2+) and viologen (1+) in films of its mixed valent molten salt on interdigitated array electrodes can be thermally and stably frozen in place in the interelectrode gaps. A study is presented of properties of the gradient-containing films, as compared to films that are non-mixed valent (V{sup 2+}) or that are mixed valent but lack concentration gradients. Comparisons of charge transport measurements show that the 2-5 {mu}m wide concentration gradients are persistent in the molten salt at lowered temperatures, where ionic motions are quenched relative to electron hopping as shown by differences in conductivity between mixed valent and non-mixed valent films as the temperature is lowered from +50 to -70{degree}C. Differences in the magnitude and shape of high-field current-voltage curves taken from mixed valent nongradient and V{sup 2+}/V{sup +} gradient-containing samples are interpreted with an electron-hopping model that includes a parameter for kinetic dispersity. Differences between the capacitance of the mixed valent and non-mixed valent phase of the viologen molten salt are consistent with the formation of an electronic space charge at the metal/redox conductor interface. 18 refs., 8 figs., 1 tab.

  20. Collectibility for Mixed Quantum States

    E-Print Network [OSTI]

    ?ukasz Rudnicki; Zbigniew Pucha?a; Pawe? Horodecki; Karol ?yczkowski

    2012-11-02T23:59:59.000Z

    Bounds analogous to entropic uncertainty relations allow one to design practical tests to detect quantum entanglement by a collective measurement performed on several copies of the state analyzed. This approach, initially worked out for pure states only [Phys. Rev. Lett. 107, 150502 (2011)], is extended here for mixed quantum states. We define collectibility for any mixed states of a multipartite system. Deriving bounds for collectibility for positive partially transposed states of given purity provides a new insight into the structure of entangled quantum states. In case of two qubits the application of complementary measurements and coincidence based detections leads to a new test of entanglement of pseudopure states.

  1. Mixed ternary heterojunction solar cell

    DOE Patents [OSTI]

    Chen, Wen S. (Seattle, WA); Stewart, John M. (Seattle, WA)

    1992-08-25T23:59:59.000Z

    A thin film heterojunction solar cell and a method of making it has a p-type layer of mixed ternary I-III-VI.sub.2 semiconductor material in contact with an n-type layer of mixed binary II-VI semiconductor material. The p-type semiconductor material includes a low resistivity copper-rich region adjacent the back metal contact of the cell and a composition gradient providing a minority carrier mirror that improves the photovoltaic performance of the cell. The p-type semiconductor material preferably is CuInGaSe.sub.2 or CuIn(SSe).sub.2.

  2. Bs Mixing at the Tevatron

    SciTech Connect (OSTI)

    Gomez-Ceballos, Guillelmo; /Cantabria Inst. of Phys.

    2006-04-01T23:59:59.000Z

    The Tevatron collider at Fermilab provides a very rich environment for the study of B{sub s} mesons. B{sub s} Mixing is the most important analysis within the B Physics program of both experiments. In this paper they summarize the most recent results on this topic from both D0 and CDF experiments. There were very important updates in both experiments after his last talk, hence the organizers warmly recommended me to include the latest available results on B{sub s} mixing, instead of what he presents there.

  3. Preshot Predictions for Defect Induced Mix (DIME) Capsules

    SciTech Connect (OSTI)

    Bradley, Paul A. [Los Alamos National Laboratory; Krasheninnikova, Natalia S. [Los Alamos National Laboratory; Tregillis, Ian L. [Los Alamos National Laboratory; Schmitt, Mark J. [Los Alamos National Laboratory

    2012-07-31T23:59:59.000Z

    In this memo, we evaluate the most probable yield and other results for the Defect Induced Mix (DIME-12A) Polar Direct Drive (PDD) capsule-only shots. We evaluate the expected yield, bang time, burn averaged ion temperature, and the average electron temperature of the Ge line-emitting region. We also include synthetic images of the capsule backlit by Cu K-{alpha} emission (8.39 keV) and core self-emission synthetic images. This memo is a companion to the maximum credible yield memo (LA-UR-12-00287) published earlier.

  4. Retail Lamps Study 3.1: Dimming, Flicker, and Power Quality Characteristics of LED A Lamps.

    SciTech Connect (OSTI)

    Royer, Michael P.; Poplawski, Michael E.; Brown, Charles C.

    2014-12-14T23:59:59.000Z

    To date, all three reports in the retail lamps series have focused on basic performance parameters, such as lumen output, efficacy, and color quality. This report goes a step further, examining the photoelectric characteristics (i.e., dimming and flicker) of a subset of lamps from CALiPER Retails Lamps Study 3. Specifically, this report focuses on the dimming, power quality, and flicker characteristics of 14 LED A lamps, as controlled by four different retail-available dimmers. The results demonstrate notable variation across the various lamps, but little variation between the four dimmers. Overall, the LED lamps: ~tended to have higher relative light output compared to the incandescent and halogen benchmark at the same dimmer output signal (RMS voltage). The lamps’ dimming curves (i.e., the relationship between control signal and relative light output) ranged from linear to very similar to the square-law curve typical of an incandescent lamp. ~generally exhibited symmetrical behavior—the same dimming curve—when measured proceeding from maximum to minimum or minimum to maximum control signal. ~mostly dimmed below 10% of full light output, with some exceptions for specific lamp and dimmer combinations ~exhibited a range of flicker characteristics, with many comparing favorably to the level typical of a magnetically-ballasted fluorescent lamp through at least a majority of the dimming range. ~ always exceeded the relative (normalized) efficacy over the dimming range of the benchmark lamps, which rapidly decline in efficacy when they are dimmed. This report generally does not attempt to rank the performance of one product compared to another, but instead focuses on the collective performance of the group versus conventional incandescent or halogen lamps, the performance of which is likely to be the baseline for a majority of consumers. Undoubtedly, some LED lamps perform better—or more similar to conventional lamps—than others. Some perform desirably for one characteristic, but not others. Consumers (and specifiers) may have a hard time distinguishing better-performing lamps from one another; at this time, physical experimentation is likely the best evaluation tool.

  5. Advances in compressible turbulent mixing

    SciTech Connect (OSTI)

    Dannevik, W.P.; Buckingham, A.C.; Leith, C.E. [eds.

    1992-01-01T23:59:59.000Z

    This volume includes some recent additions to original material prepared for the Princeton International Workshop on the Physics of Compressible Turbulent Mixing, held in 1988. Workshop participants were asked to emphasize the physics of the compressible mixing process rather than measurement techniques or computational methods. Actual experimental results and their meaning were given precedence over discussions of new diagnostic developments. Theoretical interpretations and understanding were stressed rather than the exposition of new analytical model developments or advances in numerical procedures. By design, compressibility influences on turbulent mixing were discussed--almost exclusively--from the perspective of supersonic flow field studies. The papers are arranged in three topical categories: Foundations, Vortical Domination, and Strongly Coupled Compressibility. The Foundations category is a collection of seminal studies that connect current study in compressible turbulent mixing with compressible, high-speed turbulent flow research that almost vanished about two decades ago. A number of contributions are included on flow instability initiation, evolution, and transition between the states of unstable flow onset through those descriptive of fully developed turbulence. The Vortical Domination category includes theoretical and experimental studies of coherent structures, vortex pairing, vortex-dynamics-influenced pressure focusing. In the Strongly Coupled Compressibility category the organizers included the high-speed turbulent flow investigations in which the interaction of shock waves could be considered an important source for production of new turbulence or for the enhancement of pre-existing turbulence. Individual papers are processed separately.

  6. Dark energy and particle mixing

    E-Print Network [OSTI]

    A. Capolupo; S. Capozziello; G. Vitiello

    2008-08-30T23:59:59.000Z

    We show that the vacuum condensate due to particle mixing is responsible of a dynamically evolving dark energy. In particular, we show that values of the adiabatic index close to -1 for vacuum condensates of neutrinos and quarks imply, at the present epoch, contributions to the vacuum energy compatible with the estimated upper bound on the dark energy.

  7. Updated database plus software for line-mixing in CO2 infrared spectra and their test using laboratory spectra

    E-Print Network [OSTI]

    Gamache, Robert R.

    Updated database plus software for line-mixing in CO2 infrared spectra and their test using-mixing into account and the corresponding database/software package were described and widely tested. In this study from the CDSD-296 database and the high-temperature CDSD-1000 if necessary. Previously missing

  8. LED Surgical Task Lighting Scoping Study: A Hospital Energy Alliance Project

    SciTech Connect (OSTI)

    Tuenge, Jason R.

    2011-01-17T23:59:59.000Z

    Tungsten-halogen (halogen) lamps have traditionally been used to light surgical tasks in hospitals, even though they are in many respects ill-suited to the application due to the large percentage of radiant energy outside the visible spectrum and issues with color rendering/quality. Light-emitting diode (LED) technology offers potential for adjustable color and improved color rendition/quality, while simultaneously reducing side-effects from non-visible radiant energy. It also has the potential for significant energy savings, although this is a fairly narrow application in the larger commercial building energy use sector. Based on analysis of available products and Hospital Energy Alliance member interest, it is recommended that a product specification and field measurement procedure be developed for implementation in demonstration projects.

  9. LED Lighting in a Performing Arts Building at the University of Florida

    SciTech Connect (OSTI)

    Miller, Naomi J.; Kaye, Stan; Coleman, Patricia; Wilkerson, Andrea M.; Perrin, Tess E.; Sullivan, Gregory P.

    2014-07-01T23:59:59.000Z

    The U.S. DOE GATEWAY Demonstration Program supports demonstrations of high-performance solid-state lighting (SSL) products in order to develop empirical data and experience with the in-the-field applications of this advanced lighting technology. This report describes the process and results of the 2013 - 2014 GATEWAY demonstration of SSL technology in the Nadine McGuire Theatre and Dance Pavilion at the University of Florida, Gainesville, FL. The LED solutions combined with dimming controls utilized in four interior spaces - the Acting Studio, Dance Studio, Scene Shop, and Dressing Room - received high marks from instructors, students/performers, and reduced energy use in all cases. The report discusses in depth and detail of each project area including specifications, energy savings, and user observations. The report concludes with lessons learned during the demonstration.

  10. A SUB-GRID VOLUME-OF-FLUIDS (VOF) MODEL FOR MIXING IN RESOLVED SCALE AND IN UNRESOLVED SCALE COMPUTATIONS

    SciTech Connect (OSTI)

    VOLD, ERIK L. [Los Alamos National Laboratory; SCANNAPIECO, TONY J. [Los Alamos National Laboratory

    2007-10-16T23:59:59.000Z

    A sub-grid mix model based on a volume-of-fluids (VOF) representation is described for computational simulations of the transient mixing between reactive fluids, in which the atomically mixed components enter into the reactivity. The multi-fluid model allows each fluid species to have independent values for density, energy, pressure and temperature, as well as independent velocities and volume fractions. Fluid volume fractions are further divided into mix components to represent their 'mixedness' for more accurate prediction of reactivity. Time dependent conversion from unmixed volume fractions (denoted cf) to atomically mixed (af) fluids by diffusive processes is represented in resolved scale simulations with the volume fractions (cf, af mix). In unresolved scale simulations, the transition to atomically mixed materials begins with a conversion from unmixed material to a sub-grid volume fraction (pf). This fraction represents the unresolved small scales in the fluids, heterogeneously mixed by turbulent or multi-phase mixing processes, and this fraction then proceeds in a second step to the atomically mixed fraction by diffusion (cf, pf, af mix). Species velocities are evaluated with a species drift flux, {rho}{sub i}u{sub di} = {rho}{sub i}(u{sub i}-u), used to describe the fluid mixing sources in several closure options. A simple example of mixing fluids during 'interfacial deceleration mixing with a small amount of diffusion illustrates the generation of atomically mixed fluids in two cases, for resolved scale simulations and for unresolved scale simulations. Application to reactive mixing, including Inertial Confinement Fusion (ICF), is planned for future work.

  11. Occupant satisfaction in mixed-mode buildings.

    E-Print Network [OSTI]

    Brager, Gail; Baker, Lindsay

    2008-01-01T23:59:59.000Z

    curtain walls and fluorescent lighting, led to the more common commercial building forms of today that are typically all-glass,

  12. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting on Residential and Commercial Streets in Palo Alto, CA

    SciTech Connect (OSTI)

    Myer, Michael; Kinzey, Bruce R.; Tam, Christine

    2010-06-24T23:59:59.000Z

    This report is part of a GATEWAY demonstration that replaced existing HPS streetlights with two different types of LED products and one induction product. Energy savings ranged from 6% to 44%.

  13. Long-term Testing Results for the 2008 Installation of LED Luminaires at the I-35 West Bridge in Minneapolis

    SciTech Connect (OSTI)

    Kinzey, Bruce R.; Davis, Robert G.

    2014-09-30T23:59:59.000Z

    This document reports the long-term testing results from an extended GATEWAY project that was first reported in “Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting at the I-35W Bridge, in Minneapolis, MN,” August 2009. That original report presented the results of lighting the newly reconstructed I 35W Bridge using LEDs in place of conventional high-pressure sodium (HPS) roadway luminaires, comparing energy use and illuminance levels with a simulated baseline condition. That installation was an early stage implementation of LED lighting and remains one of the oldest installations in continued operation today. This document provides an update of the LED system’s performance since its installation in September 2008.

  14. Demonstration Assessment of Light-Emitting Diode (LED) Accent Lighting at the Field Museum in Chicago, IL

    SciTech Connect (OSTI)

    Myer, Michael; Kinzey, Bruce R.

    2010-12-10T23:59:59.000Z

    This report reviews a demonstration of light-emitting diode (LED) accent lighting compared to halogen (typical) accent lighting in a gallery of the Field Museum in Chicago, IL.

  15. Design and fabrication of high-index-contrast self-assembled texture for light extraction enhancement in LEDs

    E-Print Network [OSTI]

    Sheng, Xing

    We developed a high-index-contrast photonic structure for improving the light extraction efficiency of light-emitting diodes (LEDs) by a self-assembly approach. In this approach, a two-dimensional grating can be ...

  16. CALiPER Report 20.1: Quality of Beam, Shadow, and Color in LED PAR38 Lamps

    Broader source: Energy.gov [DOE]

    View the video about CALiPER Report 20.1 which focuses on human-evaluated characteristics, including beam quality, shadow quality, and color quality in LED PAR38 lamps.

  17. Assessing the Performance of LED-Based Flashlights Available in the Kenyan Off-Grid Lighting Market

    E-Print Network [OSTI]

    Tracy, Jennifer

    2010-01-01T23:59:59.000Z

    testing of emerging off-grid White-LED illumination systems,the economics behind off-grid lighting products for smallAvailable in the Kenyan Off-Grid Lighting Market Jennifer

  18. DOE Publishes CALiPER Report on Linear (T8) LED Lamps in a 2x4...

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

    than those with a wide distribution (i.e., with a diffuse optic), and all of the linear LED lamps resulted in a higher luminaire efficiency than the fluorescent benchmark. The...

  19. GaN-Ready Aluminum Nitride Substrates for Cost-Effective, Very Low Dislocation Density III-Nitride LED's

    SciTech Connect (OSTI)

    Sandra Schujman; Leo Schowalter

    2010-10-15T23:59:59.000Z

    The objective of this project was to develop and then demonstrate the efficacy of a costeffective approach for a low defect density substrate on which AlInGaN LEDs can be fabricated. The efficacy of this “GaN-ready” substrate would then be tested by growing high efficiency, long lifetime InxGa1-xN blue LEDs. The approach used to meet the project objectives was to start with low dislocation density AlN single-crystal substrates and grow graded AlxGa1-xN layers on top. Pseudomorphic AlxGa1-xN epitaxial layers grown on bulk AlN substrates were used to fabricate light emitting diodes and demonstrate better device performance as a result of the low defect density in these layers when benched marked against state-of-the-art LEDs fabricated on sapphire substrates. The pseudomorphic LEDs showed excellent output powers compared to similar wavelength devices grown on sapphire substrates, with lifetimes exceeding 10,000 hours (which was the longest time that could reliably be estimated). In addition, high internal quantum efficiencies were demonstrated at high driving current densities even though the external quantum efficiencies were low due to poor photon extraction. Unfortunately, these pseudomorphic LEDs require high Al content so they emit in the ultraviolet. Sapphire based LEDs typically have threading dislocation densities (TDD) > 108 cm-2 while the pseudomorphic LEDs have TDD ? 105 cm-2. The resulting TDD, when grading the AlxGa1-xN layer all the way to pure GaN to produce a “GaN-ready” substrate, has varied between the mid 108 down to the 106 cm-2. These inconsistencies are not well understood. Finally, an approach to improve the LED structures on AlN substrates for light extraction efficiency was developed by thinning and roughening the substrate.

  20. Fundamental Studies and Development of III-N Visible LEDs for High-Power Solid-State Lighting Applications

    SciTech Connect (OSTI)

    Dupuis, Russell

    2012-02-29T23:59:59.000Z

    The goal of this program is to understand in a fundamental way the impact of strain, defects, polarization, and Stokes loss in relation to unique device structures upon the internal quantum efficiency (IQE) and efficiency droop (ED) of III-nitride (III-N) light-emitting diodes (LEDs) and to employ this understanding in the design and growth of high-efficiency LEDs capable of highly-reliable, high-current, high-power operation. This knowledge will be the basis for our advanced device epitaxial designs that lead to improved device performance. The primary approach we will employ is to exploit new scientific and engineering knowledge generated through the application of a set of unique advanced growth and characterization tools to develop new concepts in strain-, polarization-, and carrier dynamics-engineered and low-defect materials and device designs having reduced dislocations and improved carrier collection followed by efficient photon generation. We studied the effects of crystalline defect, polarizations, hole transport, electron-spillover, electron blocking layer, underlying layer below the multiplequantum- well active region, and developed high-efficiency and efficiency-droop-mitigated blue LEDs with a new LED epitaxial structures. We believe new LEDs developed in this program will make a breakthrough in the development of high-efficiency high-power visible III-N LEDs from violet to green spectral region.

  1. High-resolution inverse Raman and resonant-wave-mixing spectroscopy

    SciTech Connect (OSTI)

    Rahn, L.A. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01T23:59:59.000Z

    These research activities consist of high-resolution inverse Raman spectroscopy (IRS) and resonant wave-mixing spectroscopy to support the development of nonlinear-optical techniques for temperature and concentration measurements in combustion research. Objectives of this work include development of spectral models of important molecular species needed to perform coherent anti-Stokes Raman spectroscopy (CARS) measurements and the investigation of new nonlinear-optical processes as potential diagnostic techniques. Some of the techniques being investigated include frequency-degenerate and nearly frequency-degenerate resonant four-wave-mixing (DFWM and NDFWM), and resonant multi-wave mixing (RMWM).

  2. Neutrino mixing, flavor states and dark energy

    E-Print Network [OSTI]

    M. Blasone; A. Capolupo; S. Capozziello; G. Vitiello

    2007-11-06T23:59:59.000Z

    We shortly summarize the quantum field theory formalism for the neutrino mixing and report on recent results showing that the vacuum condensate induced by neutrino mixing can be interpreted as a dark energy component of the Universe.

  3. Estimating a mixed strategy employing maximum entropy

    E-Print Network [OSTI]

    Golan, Amos; Karp, Larry; Perloff, Jeffrey M.

    1996-01-01T23:59:59.000Z

    MIXED STRATEGY EMPLOYING MAXIMUM ENTROPY by Amos Golan LarryMixed Strategy Employing Maximum Entropy Amos Golan Larry S.Abstract Generalized maximum entropy may be used to estimate

  4. HETEROGENEOUS REBURNING BY MIXED FUELS

    SciTech Connect (OSTI)

    Wei-Yin Chen; Benson B. Gathitu

    2005-01-14T23:59:59.000Z

    Recent studies of heterogeneous reburning, i.e., reburning involving a coal-derived char, have elucidated its variables, kinetics and mechanisms that are valuable to the development of a highly efficient reburning process. Young lignite chars contain catalysts that not only reduce NO, but they also reduce HCN that is an important intermediate that recycles to NO in the burnout zone. Gaseous CO scavenges the surface oxides that are formed during NO reduction, regenerating the active sites on the char surface. Based on this mechanistic information, cost-effective mixed fuels containing these multiple features has been designed and tested in a simulated reburning apparatus. Remarkably high reduction of NO and HCN has been observed and it is anticipated that mixed fuel will remove 85% of NO in a three-stage reburning process.

  5. Heterogeneous Reburning By Mixed Fuels

    SciTech Connect (OSTI)

    Anderson Hall

    2009-03-31T23:59:59.000Z

    Recent studies of heterogeneous reburning, i.e., reburning involving a coal-derived char, have elucidated its variables, kinetics and mechanisms that are valuable to the development of a highly efficient reburning process. Young lignite chars contain catalysts that not only reduce NO, but they also reduce HCN that is an important intermediate that recycles to NO in the burnout zone. Gaseous CO scavenges the surface oxides that are formed during NO reduction, regenerating the active sites on the char surface. Based on this mechanistic information, cost-effective mixed fuels containing these multiple features has been designed and tested in a simulated reburning apparatus. Remarkably high reduction of NO and HCN has been observed and it is anticipated that mixed fuel will remove 85% of NO in a three-stage reburning process.

  6. Mixing

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

    Pyrocamera t 0 5 ps 10 ps Pyrocamera Diffractive grating wavenumber 1.3 cm -1 Fourier transform Measured Simulated :) Single-shot :) Simple reliable :) Indiv. pulse...

  7. Optimization Online - Analysis of mixed integer programming ...

    E-Print Network [OSTI]

    Thiago Henrique Nogueira

    2014-07-15T23:59:59.000Z

    Jul 15, 2014 ... Analysis of mixed integer programming formulations for single machine scheduling problems with sequence dependent setup times and ...

  8. Dark energy induced by neutrino mixing

    E-Print Network [OSTI]

    Antonio Capolupo; Salvatore Capozziello; Giuseppe Vitiello

    2006-12-11T23:59:59.000Z

    The energy content of the vacuum condensate induced by the neutrino mixing is interpreted as dynamically evolving dark energy.

  9. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting at the I-35W Bridge, Minneapolis, MN

    SciTech Connect (OSTI)

    Kinzey, Bruce R.; Myer, Michael

    2009-08-31T23:59:59.000Z

    This report describes the process and results of a demonstration of solid-state lighting (SSL) technology conducted in 2009 at the recently reconstructed I-35W bridge in Minneapolis, MN. The project was supported under the U.S. Department of Energy (DOE) Solid-State Lighting GATEWAY Technology Demonstration Program. Other participants in the demonstration project included the Minnesota Department of Transportation (Mn/DOT), Federal Highways Administration (FHWA), and BetaLED™ (a division of Ruud Lighting). Pacific Northwest National Laboratory (PNNL) conducted the measurements and analysis of the results. DOE has implemented a three-year evaluation of the LED luminaires in this installation in order to develop new longitudinal field data on LED performance in a challenging, real-world environment. This document provides information through the initial phase of the I-35W bridge project, up to and including the opening of the bridge to the public and the initial feedback received on the LED lighting installation from bridge users. Initial findings of the evaluation are favorable, with minimum energy savings level of 13% for the LED installation relative to the simulated base case using 250W high-pressure sodium (HPS) fixtures. The LEDs had an average illuminance level of 0.91 foot candles compared to 1.29 fc for the HPS lamps. The LED luminaires cost $38,000 more than HPS lamps, yielding a lengthy payback period, however the bridge contractor had offered to include the LED luminaires as part of the construction package at no additional cost. One potentially significant benefit of the LEDs in this installation is avoiding rolling lane closures on the heavily-traveled interstate bridge for the purpose of relamping the HPS fixtures. Rolling lane closures involve multiple crew members and various maintenance and safety vehicles, diversion of traffic, as well as related administrative tasks (e.g., approvals, scheduling, etc.). Mn/DOT records show an average cost of relamping fixtures along interstate roadways of between $130-150 per pole. The previous bridge saw a lamp mortality rate of approximately 50% every two years, though the new bridge was designed to minimize many of the vibration issues. A voluntary Web-based feedback survey of nearly 500 self-described bridge users showed strong preference for the LED lighting - positive comments outnumbered negative ones by about five-to-one.

  10. High Temperatures & Electricity Demand

    E-Print Network [OSTI]

    High Temperatures & Electricity Demand An Assessment of Supply Adequacy in California Trends.......................................................................................................1 HIGH TEMPERATURES AND ELECTRICITY DEMAND.....................................................................................................................7 SECTION I: HIGH TEMPERATURES AND ELECTRICITY DEMAND ..........................9 BACKGROUND

  11. Color stable phosphors for LED lamps and methods for preparing them

    DOE Patents [OSTI]

    Murphy, James Edward; Setlur, Anant Achyut; Camardello, Samuel Joseph

    2013-11-26T23:59:59.000Z

    An LED lamp includes a light source configured to emit radiation with a peak intensity at a wavelength between about 250 nm and about 550 nm; and a phosphor composition configured to be radiationally coupled to the light source. The phosphor composition includes particles of a phosphor of formula I, said particles having a coating composition disposed on surfaces thereof; ((Sr.sub.1-zM.sub.z).sub.1-(x+w)A.sub.wCe.sub.x).sub.3(Al.sub.1-ySi.sub.y-)O.sub.4+y+3(x-w)F.sub.1-y-3(x-w) I wherein the coating composition comprises a material selected from aluminum oxide, magnesium oxide, calcium oxide, barium oxide, strontium oxide, zinc oxide, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, barium hydroxide, strontium hydroxide, zinc hydroxide, aluminum phosphate, magnesium phosphate, calcium phosphate, barium phosphate, strontium phosphate, and combinations thereof; and A is Li, NA, K, or Rb, or a combination thereof; M is Ca, Ba, Mg, Zn, or a combination thereof; and 0

  12. Replacement of Lighting Fixtures with LED Energy Efficient Lights at the Parking Facility, Milwaukee, Wisconsin

    SciTech Connect (OSTI)

    David Brien

    2012-06-21T23:59:59.000Z

    The Forest County Potawatomi Community (FCPC or Tribe) owns a six-story parking facility adjacent to its Potawatomi Bingo Casino (the Casino) in Milwaukee, Wisconsin, as well as a valet parking facility under the Casino (collectively, the Parking Facility). The Parking Facility contained 205-watt metal halide-type lights that, for security reasons, operated 24 hours per day, 7 days per week. Starting on August 30, 2010, the Tribe replaced these fixtures with 1,760 state-of-the-art, energy efficient 55-Watt LED lights. This project resulted in an immediate average reduction in monthly peak demand of 238 kW over the fourth quarter of 2010. The average reduction in monthly peak demand from October 1 through December 31, 2010 translates into a forecast annual electrical energy reduction of approximately 1,995,000 kWh or 47.3% of the pre-project demand. This project was technically effective, economically feasible, and beneficial to the public not only in terms of long term energy efficiency and associated emissions reductions, but also in the short-term jobs provided for the S.E. Wisconsin region. The project was implemented, from approval by U.S. Department of Energy (DOE) to completion, in less than 6 months. The project utilized off-the-shelf proven technologies that were fabricated locally and installed by local trade contractors.

  13. B0-B0bar mixing

    E-Print Network [OSTI]

    Olivier Schneider

    2008-06-30T23:59:59.000Z

    The subject of particle-antiparticle mixing in the neutral B meson systems is reviewed. The formalism of B0-B0bar mixing is recalled and basic Standard Model predictions are given, before experimental issues are discussed and the latest combinations of experimental results on mixing parameters are presented, including those on mixing-induced CP violation, mass differences, and decay-width differences. Finally, time-integrated mixing results are used to improve our knowledge on the fractions of the various b-hadron species produced in Z decays and at high-energy colliders.

  14. B0-B0bar mixing

    E-Print Network [OSTI]

    Olivier Schneider

    2006-06-17T23:59:59.000Z

    The subject of particle-antiparticle mixing in the neutral B meson systems is reviewed. The formalism of B0-B0bar mixing is recalled and basic Standard Model predictions are given, before experimental issues are discussed and the latest combinations of experimental results on mixing parameters are presented, including those on mixing-induced CP violation, mass differences, and decay-width differences. Finally, time-integrated mixing results are used to improve our knowledge on the fractions of the various b-hadron species produced in Z decays and at high-energy colliders.

  15. Tailored mixing inside a translating droplet

    E-Print Network [OSTI]

    Rodolphe Chabreyrie; Dmitri Vainchtein; Cristel Chandre; Pushpendra Singh; Nadine Aubry

    2008-03-03T23:59:59.000Z

    Tailored mixing inside individual droplets could be useful to ensure that reactions within microscopic discrete fluid volumes, which are used as microreactors in ``digital microfluidic'' applications, take place in a controlled fashion. In this article we consider a translating spherical liquid drop to which we impose a time periodic rigid-body rotation. Such a rotation not only induces mixing via chaotic advection, which operates through the stretching and folding of material lines, but also offers the possibility of tuning the mixing by controlling the location and size of the mixing region. Tuned mixing is achieved by judiciously adjusting the amplitude and frequency of the rotation, which are determined by using a resonance condition and following the evolution of adiabatic invariants. As the size of the mixing region is increased, complete mixing within the drop is obtained.

  16. Expandable mixing section gravel and cobble eductor

    DOE Patents [OSTI]

    Miller, Arthur L. (Kenyon, MN); Krawza, Kenneth I. (Lakeville, MN)

    1997-01-01T23:59:59.000Z

    In a hydraulically powered pump for excavating and transporting slurries in hich it is immersed, the improvement of a gravel and cobble eductor including an expandable mixing section, comprising: a primary flow conduit that terminates in a nozzle that creates a water jet internal to a tubular mixing section of the pump when water pressure is applied from a primary supply flow; a tubular mixing section having a center line in alignment with the nozzle that creates a water jet; a mixing section/exit diffuser column that envelopes the flexible liner; and a secondary inlet conduit that forms an opening at a bas portion of the column and adjacent to the nozzle and water jet to receive water saturated gravel as a secondary flow that mixes with the primary flow inside of the mixing section to form a combined total flow that exits the mixing section and decelerates in the exit diffuser.

  17. Corium quench in deep pool mixing experiments

    SciTech Connect (OSTI)

    Spencer, B.W.; McUmber, L.; Gregorash, D.; Aeschlimann, R.; Sienicki, J.J.

    1985-01-01T23:59:59.000Z

    The results of two recent corium-water thermal interaction (CWTI) tests are described in which a stream of molten corium was poured into a deep pool of water in order to determine the mixing behavior, the corium-to-water heat transfer rates, and the characteristic sizes of the quenched debris. The corium composition was 60% UO/sub 2/, 16% ZrO/sub 2/, and 24% stainless steel by weight; its initial temperature was 3080 K, approx.160 K above the oxide phase liquidus temperature. The corium pour stream was a single-phase 2.2 cm dia liquid column which entered the water pool in film boiling at approx.4 m/s. The water subcooling was 6 and 75C in the two tests. Test results showed that with low subcooling, rapid steam generation caused the pool to boil up into a high void fraction regime. In contrast, with large subcooling no net steam generation occurred, and the pool remained relatively quiescent. Breakup of the jet appeared to occur by surface stripping. In neither test was the breakup complete during transit through the 32 cm deep water pool, and molten corium channeled to the base where it formed a melt layer. The characteristic heat transfer rates measured 3.5 MJ/s and 2.7 MJ/s during the fall stage for small and large subcooling, respectively; during the initial stage of bed quench, the surface heat fluxes measured 2.4 MW/m/sup 2/ and 3.7 MW/m/sup 2/, respectively. A small mass of particles was formed in each test, measuring typically 0.1 to 1 mm and 1 to 5 mm dia for the large and small subcooling conditions, respectively. 9 refs., 13 figs., 1 tab.

  18. Orifice mixing of immiscible liquids

    E-Print Network [OSTI]

    McDonough, Joseph Aloysius

    1960-01-01T23:59:59.000Z

    solution (7). The present study of orif1ce mixing is a continuation of previous research on this project which yielded a relationship explaining the effect of operating conditions upon the format1on of 1nterfacial area for the system water-kerosene.... The experimental technique evolved by Helch (18), Vesselhoff (19), McNair (8), and Scott (IA) was changed only slightly. Their work on water-kerosene was repeated for the liquid pairs trichloroethylene-water, heptanol-water, 20 per oent aqueous sucrose-kerosene...

  19. Tensor B mode and stochastic Faraday mixing

    E-Print Network [OSTI]

    Massimo Giovannini

    2014-06-12T23:59:59.000Z

    This paper investigates the Faraday effect as a different source of B mode polarization. The E mode polarization is Faraday rotated provided a stochastic large-scale magnetic field is present prior to photon decoupling. In the first part of the paper we discuss the case where the tensor modes of the geometry are absent and we argue that the B mode recently detected by the Bicep2 collaboration cannot be explained by a large-scale magnetic field rotating, through the Faraday effect, the well established E mode polarization. In this case, the observed temperature autocorrelations would be excessively distorted by the magnetic field. In the second part of the paper the formation of Faraday rotation is treated as a stationary, random and Markovian process with the aim of generalizing a set of scaling laws originally derived in the absence of the tensor modes of the geometry. We show that the scalar, vector and tensor modes of the brightness perturbations can all be Faraday rotated even if the vector and tensor parts of the effect have been neglected, so far, by focussing the attention on the scalar aspects of the problem. The mixing between the power spectra of the E mode and B mode polarizations involves a unitary transformation depending nonlinearly on the Faraday rotation rate. The present approach is suitable for a general scrutiny of the polarization observables and of their frequency dependence.

  20. Jade Sky Technologies Partners with CLTC on LED Replacement Lamp Upgrade Project UC Davis' California Lighting Technology Center will utilize Jade Sky Technologies' driver ICs to help spur

    E-Print Network [OSTI]

    California at Davis, University of

    Jade Sky Technologies Partners with CLTC on LED Replacement Lamp Upgrade Project UC Davis and power factor. "JST shares our goal of making the transition to LED lamps a satisfying experience of cost-effective, easy-to-use LED lighting solutions Milpitas, Calif. ­ October 15, 2013 ­ Jade Sky

  1. Current crowding in GaInN / GaN LEDs grown on insulating substrates X. Guo, E. F. Schubert and J. Jahns

    E-Print Network [OSTI]

    Jahns, Jürgen

    Current crowding in GaInN / GaN LEDs grown on insulating substrates X. Guo, E. F. Schubert and J spreading in a mesa-structure GaN-based LED grown on an insulating or semi-insulating substrate. (b. Jahns Current crowding in mesa-structure GaInN/GaN light-emitting diodes (LEDs) grown on insulating

  2. Mixed waste characterization reference document

    SciTech Connect (OSTI)

    NONE

    1997-09-01T23:59:59.000Z

    Waste characterization and monitoring are major activities in the management of waste from generation through storage and treatment to disposal. Adequate waste characterization is necessary to ensure safe storage, selection of appropriate and effective treatment, and adherence to disposal standards. For some wastes characterization objectives can be difficult and costly to achieve. The purpose of this document is to evaluate costs of characterizing one such waste type, mixed (hazardous and radioactive) waste. For the purpose of this document, waste characterization includes treatment system monitoring, where monitoring is a supplement or substitute for waste characterization. This document establishes a cost baseline for mixed waste characterization and treatment system monitoring requirements from which to evaluate alternatives. The cost baseline established as part of this work includes costs for a thermal treatment technology (i.e., a rotary kiln incinerator), a nonthermal treatment process (i.e., waste sorting, macronencapsulation, and catalytic wet oxidation), and no treatment (i.e., disposal of waste at the Waste Isolation Pilot Plant (WIPP)). The analysis of improvement over the baseline includes assessment of promising areas for technology development in front-end waste characterization, process equipment, off gas controls, and monitoring. Based on this assessment, an ideal characterization and monitoring configuration is described that minimizes costs and optimizes resources required for waste characterization.

  3. Argonne is a partner in the Argonne-Northwestern Solar Energy Research Center led by Northwestern University. Argonne is a partner in the Center for Emergent Superconductivity led by Brookhaven National Laboratory.

    E-Print Network [OSTI]

    Kemner, Ken

    Argonne is a partner in the Argonne-Northwestern Solar Energy Research Center led by Northwestern Conductivity (CES) W. Kwok (MSD) Argonne-Northwestern Solar Energy Research (ANSER) M. Pellin (MSD) #12; Administrative Support J. Hogan and G. Cutinello Chemical Sciences & Engineering (CSE) E.E. Bunel High Energy

  4. NREL Provides Guidance to Improve Air Mixing and Thermal Comfort in Homes (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-02-01T23:59:59.000Z

    NREL research determines optimal HVAC system design for proper air mixing and thermal comfort in homes. As U.S. homes become more energy efficient, heating, ventilation, and cooling (HVAC) systems will be downsized, and the air flow volumes required to meet heating and cooling loads may be too small to maintain uniform room air mixing-which can affect thermal comfort. Researchers at the National Renewable Energy Laboratory (NREL) evaluated the performance of high sidewall air supply inlets and confirmed that these systems can achieve good air mixing and provide suitable comfort levels for occupants. Using computational fluid dynamics modeling, NREL scientists tested the performance of high sidewall supply air jets over a wide range of parameters including supply air temperature, air velocity, and inlet size. This technique uses the model output to determine how well the supply air mixes with the room air. Thermal comfort is evaluated by monitoring air temperature and velocity in more than 600,000 control volumes that make up the occupied zone of a single room. The room has an acceptable comfort level when more than 70% of the control volumes meet the comfort criteria on both air temperature and velocity. The study shows that high sidewall supply air jets achieve uniform mixing in a room, which is essential for providing acceptable comfort levels. The study also provides information required to optimize overall space conditioning system design in both heating and cooling modes.

  5. Superconductivity in Metal-mixed Ion-Implanted Polymer Films

    E-Print Network [OSTI]

    A. P. Micolich; E. Tavenner; B. J. Powell; A. R. Hamilton; M. T. Curry; R. E. Giedd; P. Meredith

    2006-03-15T23:59:59.000Z

    Ion-implantation of normally insulating polymers offers an alternative to depositing conjugated organics onto plastic films to make electronic circuits. We used a 50 keV nitrogen ion beam to mix a thin 10 nm Sn/Sb alloy film into the sub-surface of polyetheretherketone (PEEK) and report the low temperature properties of this material. We observed metallic behavior, and the onset of superconductivity below 3 K. There are strong indications that the superconductivity does not result from a residual thin-film of alloy, but instead from a network of alloy grains coupled via a weakly conducting, ion-beam carbonized polymer matrix.

  6. Demonstration Assessment of LED Roadway Lighting: NE Cully Boulevard Portland, OR

    SciTech Connect (OSTI)

    Royer, Michael P.; Poplawski, Michael E.; Tuenge, Jason R.

    2012-06-29T23:59:59.000Z

    A new roadway lighting demonstration project was initiated in late 2010, which was planned in conjunction with other upgrades to NE Cully Boulevard, a residential collector road in the northeast area of Portland, OR. With the NE Cully Boulevard project, the Portland Bureau of Transportation hoped to demonstrate different light source technologies and different luminaires side-by-side. This report documents the initial performance of six different newly installed luminaires, including three LED products, one induction product, one ceramic metal halide product, and one high-pressure sodium (HPS) product that represented the baseline solution. It includes reported, calculated, and measured performance; evaluates the economic feasibility of each of the alternative luminaires; and documents user feedback collected from a group of local Illuminating Engineering Society (IES) members that toured the site. This report does not contain any long-term performance evaluations or laboratory measurements of luminaire performance. Although not all of the installed products performed equally, the alternative luminaires generally offered higher efficacy, more appropriate luminous intensity distributions, and favorable color quality when compared to the baseline HPS luminaire. However, some products did not provide sufficient illumination to all areas—vehicular drive lanes, bicycle lanes, and sidewalks—or would likely fail to meet design criteria over the life of the installation due to expected depreciation in lumen output. While the overall performance of the alternative luminaires was generally better than the baseline HPS luminaire, cost remains a significant barrier to widespread adoption. Based on the cost of the small quantity of luminaires purchased for this demonstration, the shortest calculated payback period for one of the alternative luminaire types was 17.3 years. The luminaire prices were notably higher than typical prices for currently available luminaires purchased in larger quantities. At prices that are more typical, the payback would be less than 10 years. In addition to the demonstration luminaires, a networked control system was installed for additional evaluation and demonstration purposes. The capability of control system to measure luminaire input power was explored in this study. A more exhaustive demonstration and evaluation of the control system will be the subject of future GATEWAY report(s).

  7. Mixing in thermally stratified nonlinear spin-up with uniform boundary fluxes

    SciTech Connect (OSTI)

    Baghdasarian, Meline; Pacheco-Vega, Arturo [Department of Mechanical Engineering, California State University, Los Angeles, Los Angeles, California 90032 (United States); Pacheco, J. Rafael, E-mail: rpacheco@asu.edu [SAP Americas Inc., Scottsdale, Arizona 85251 (United States); School of Mathematical and Statistical Sciences, Arizona State University, Tempe, Arizona 85287 (United States); Environmental Fluid Dynamics Laboratories, Department of Civil Engineering and Geological Sciences, The University of Notre Dame, South Bend, Indiana 46556 (United States); Verzicco, Roberto [Dipartimento di Ingegneria Meccanica, Universita di Roma “Tor Vergata”, Via del Politecnico 1, 00133, Roma (Italy); PoF, University of Twente, 7500 AE Enschede (Netherlands)

    2014-09-15T23:59:59.000Z

    Studies of stratified spin-up experiments in enclosed cylinders have reported the presence of small pockets of well-mixed fluids but quantitative measurements of the mixedness of the fluid has been lacking. Previous numerical simulations have not addressed these measurements. Here we present numerical simulations that explain how the combined effect of spin-up and thermal boundary conditions enhances or hinders mixing of a fluid in a cylinder. The energy of the system is characterized by splitting the potential energy into diabatic and adiabatic components, and measurements of efficiency of mixing are based on both, the ratio of dissipation of available potential energy to forcing and variance of temperature. The numerical simulations of the Navier–Stokes equations for the problem with different sets of thermal boundary conditions at the horizontal walls helped shed some light on the physical mechanisms of mixing, for which a clear explanation was absent.

  8. Optimal Control of Evolution Mixed Variational Inclusions

    SciTech Connect (OSTI)

    Alduncin, Gonzalo, E-mail: alduncin@geofisica.unam.mx [Universidad Nacional Autónoma de México, Departamento de Recursos Naturales, Instituto de Geofísica (Mexico)

    2013-12-15T23:59:59.000Z

    Optimal control problems of primal and dual evolution mixed variational inclusions, in reflexive Banach spaces, are studied. The solvability analysis of the mixed state systems is established via duality principles. The optimality analysis is performed in terms of perturbation conjugate duality methods, and proximation penalty-duality algorithms to mixed optimality conditions are further presented. Applications to nonlinear diffusion constrained problems as well as quasistatic elastoviscoplastic bilateral contact problems exemplify the theory.

  9. Alan Turing's fundamental contributions to computing led to the development of modern computing technology, and his work conti-

    E-Print Network [OSTI]

    Teuscher, Christof

    Alan Turing's fundamental contributions to computing led to the development of modern computing phyllotaxis and connectionism. AlanTuring: Life and Legacy of a Great Thinker Approx.584 p.,77 illus-mail:orders@springer.de · Internet:www.springer.de Available from ____copies: Teuscher,C.(Ed): Alan Turing: Life and Legacy

  10. Scientists at the National Renewable Energy Laboratory (NREL) invent a deep green LED that can lead to higher-efficiency

    E-Print Network [OSTI]

    Scientists at the National Renewable Energy Laboratory (NREL) invent a deep green LED that can lead by the so-called "green gap:"the inability to develop light in the green spectrum that can be combined with red and blue to produce white light. NREL researchers conceptualized a green emission by taking

  11. Hydration reactions associated with eclogite-facies metamor-phism of granulites in the Norwegian Caledonides led to the formation

    E-Print Network [OSTI]

    Svensen, Henrik

    in the Norwegian Caledonides led to the formation of saline brines with exceptional compositions. Primary omphacite a plethora of solid phases.A total of 18 different minerals have been identified in multiphase brines, and 12 granulite by the increasingly saline brine during K-feldspar breakdown. INTRODUCTION Primary brine fluid

  12. DOE Publishes CALiPER Report on Dimming, Flicker, and Power Quality Characteristics of LED PAR38 Lamps

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released Report 20.2, which is part of a series of investigations on LED PAR38 lamps. Report 20.2 focuses on dimming, flicker, and power quality...

  13. Screening of antifeedant activity in brain extracts led to the identification of sulfakinin as a satiety promoter in

    E-Print Network [OSTI]

    Belles, Xavier

    , Institut de Biologia Molecular de Barcelona, Spain; 2 Department of Organic Chemistry, Facultat de Qui. The study of the mechanisms that regulate this cycle led us to look for food-intake inhibitors in brain) GHMRFamide (Pea-SK). A synthetic version of the peptide inhibited food intake when injected at doses of 1 mg

  14. The light-emitting diode (LED) is an fairly new kind of light source found currently in

    E-Print Network [OSTI]

    The light-emitting diode (LED) is an fairly new kind of light source found currently in only a few applications, such as traffic lights and exit signs. As a relatively untested technology, luminaire this technology an ideal replacement for less efficient incandescent light sources, particularly in applications

  15. Off-grid energy services for the poor: Introducing LED lighting in the Millennium Villages Project in Malawi

    E-Print Network [OSTI]

    Modi, Vijay

    ) powered by batteries, which are in turn charged by grid electricity or small solar panels, have emerged 2009 Keywords: Solar Lighting Development a b s t r a c t Lanterns that use light-emitting diodes (LEDs as a cost-competitive alternative to kerosene and other fuel-based lighting technologies, offering brighter

  16. Research Support in Hungary Machine scheduling LED public lighting Microsimulation in public transportation Finally Optimization and Operation Research methods for

    E-Print Network [OSTI]

    Balázs, Bánhelyi

    Euros per full time researcher year. The Hungarian research support scheme has several other smallerResearch Support in Hungary Machine scheduling LED public lighting Microsimulation in public transportation Finally Optimization and Operation Research methods for Real Life Industrial Problems Tibor

  17. GaN/ZnO and AlGaN/ZnO heterostructure LEDs: growth, fabrication, optical and electrical characterization

    E-Print Network [OSTI]

    Wetzel, Christian M.

    GaN/ZnO and AlGaN/ZnO heterostructure LEDs: growth, fabrication, optical and electrical 12180-3590, U.S.A. ABSTRACT The wide bandgap polar semiconductors GaN and ZnO and their related alloys fields, and surface terminations. With a small lattice mismatch of ~1.8 % between GaN and Zn

  18. DISCOVER-AQ Outlook for Friday, July 21, 2011 High surface temperatures of near 100 F today in the study region have led to substantial ozone

    E-Print Network [OSTI]

    Orange for PM2.5 today, which is the first time that has occurred during DISCOVER-AQ. South and SW winds expected. Southerly winds continue to bring moisture into our region. 500 mb NAM at 2 PM. #12;Tomorrow Saturday: Heat and humidity sticks around. Sunday: Hot, sticky, and cloud coverage > 50%. Light Winds Juicy

  19. Seesaw enhancement of lepton mixing

    SciTech Connect (OSTI)

    Smirnov, A.Y. (Institute for Advanced Study, Princeton, New Jersey 08540 (United States) International Centre for Theoretical Physics, 34100 Trieste (Italy) Institute for Nuclear Research, 117312 Moscow (Russian Federation))

    1993-10-01T23:59:59.000Z

    The seesaw mechanism of neutrino mass generation may enhance lepton mixing up to maximal even if the Dirac mass matrices of leptons have a structure similar to that in the quark sector. Two sets of conditions for such an enhancement are found. The first one includes the seesaw generation of heavy Majorana masses for right-handed neutrinos and a universality of Yukawa couplings which can follow from the unification of neutrinos with new superheavy neutral leptons. The second set is related to the lepton number symmetry of the Yukawa interactions in the Dirac basis of neutrinos. Models which realize these conditions have a strong hierarchy or strong degeneration of Majorana masses of the right-handed neutrinos.

  20. Hygroscopic Properties of Internally Mixed Particles Composed...

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

    composed of sea salts and water soluble organic compounds of anthropogenic origin. Mixing of sea salt and organic components has profound effects on the evolving chemical...

  1. Optimization Online - Convex Quadratic Relaxations for Mixed ...

    E-Print Network [OSTI]

    Hassan L. Hijazi

    2013-09-30T23:59:59.000Z

    Sep 30, 2013 ... Convex Quadratic Relaxations for Mixed-Integer Nonlinear Programs in Power Systems. Hassan L. Hijazi (hassan.hijazi ***at*** nicta.com.au)

  2. Independent Oversight Review, Advanced Mixed Waste Treatment...

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

    April 2013 Review of Radiation Protection Program Implementation at the Advanced Mixed Waste Treatment Project of the Idaho Site This report documents an independent review of...

  3. Optimization Online - Concrete Structure Design Using Mixed ...

    E-Print Network [OSTI]

    Andres Guerra

    2009-11-26T23:59:59.000Z

    Nov 26, 2009 ... Abstract: We present a mixed-integer nonlinear programming (MINLP) formulation to achieve minimum-cost designs for reinforced concrete ...

  4. TANK MIXING STUDY WITH FLOW RECIRCULATION

    SciTech Connect (OSTI)

    Lee, S.

    2014-06-25T23:59:59.000Z

    The primary objective of this work is to quantify the mixing time when two miscible fluids are mixed by one recirculation pump and to evaluate adequacy of 2.5 hours of pump recirculation to be considered well mixed in SRS tanks, JT-71/72. The work scope described here consists of two modeling analyses. They are the steady state flow pattern analysis during pump recirculation operation of the tank liquid and transient species transport calculations based on the initial steady state flow patterns. The modeling calculations for the mixing time are performed by using the 99% homogeneity criterion for the entire domain of the tank contents.

  5. Lanthanide doped strontium barium mixed halide scintillators

    SciTech Connect (OSTI)

    Gundiah, Gautam; Bizarri, Gregory; Hanrahan, Stephen M; Bourret-Courchesne, Edith; Derenzo, Stephen E

    2013-07-16T23:59:59.000Z

    The present invention provides for a composition comprising an inorganic scintillator comprising a lanthanide-doped strontium barium mixed halide useful for detecting nuclear material.

  6. Optimization Online - Mixed-Integer Nonlinear Optimization

    E-Print Network [OSTI]

    Pietro Belotti

    2012-12-02T23:59:59.000Z

    Dec 2, 2012 ... Mixed-Integer Nonlinear Optimization. Pietro Belotti(pbelott ***at*** clemson.edu) Sven Leyffer(leyffer ***at*** mcs.anl.gov) Christian ...

  7. Laboratory Evaluation of Hot-Mix Asphalt Concrete Fatigue Cracking Resistance

    E-Print Network [OSTI]

    Jamison, Brandon Parker

    2012-02-14T23:59:59.000Z

    that the crack initiates in the center of the specimen, including Walubita et al. (5), Mohammad et al. (10), and Mull et al. (21). Notch depths vary depending on many factors such as specimen thickness, diameter, loading rate, test temperature, and mix type...

  8. Electromagnetic mixed waste processing system for asbestos decontamination

    SciTech Connect (OSTI)

    Kasevich, R.S.; Vaux, W. [KAI Technologies, Inc., Portsmouth, NH (United States); Ulerich, N. [Westinghouse Electric Corp., Pittsburgh, PA (United States). Science and Technology Center; Nocito, T. [Ohio DSI Corporation, New York (New York)

    1996-12-31T23:59:59.000Z

    The overall objective of this three-phase program is to develop an integrated process for treating asbestos-containing material that is contaminated with radioactive and hazardous constituents. The integrated process will attempt to minimize processing and disposal costs. The objectives of Phase 1 were to establish the technical feasibility of asbestos decomposition, inorganic radionuclide nd heavy metal removal, and organic volatilization. Phase 1 resulted in the successful bench-scale demonstration of the elements required to develop a mixed waste treatment process for asbestos-containing material (ACM) contaminated with radioactive metals, heavy metals, and organics. Using the Phase 1 data, a conceptual process was developed. The Phase 2 program, currently in progress, is developing an integrated system design for ACM waste processing. The Phase 3 program will target demonstration of the mixed waste processing system at a DOE facility. The electromagnetic mixed waste processing system employs patented technologies to convert DOE asbestos to a non-hazardous, radionuclide-free, stable waste. The dry, contaminated asbestos is initially heated with radiofrequency energy to remove organic volatiles. Second,the radionuclides are removed by solvent extraction coupled with ion exchange solution treatment. Third, the ABCOV method converts the asbestos to an amorphous silica suspension at low temperature (100{degrees}C). Finally the amorphous silica is solidified for disposal.

  9. Measurements and Models for Hazardous chemical and Mixed Wastes

    SciTech Connect (OSTI)

    Laurel A. Watts; Cynthia D. Holcomb; Stephanie L. Outcalt; Beverly Louie; Michael E. Mullins; Tony N. Rogers

    2002-08-21T23:59:59.000Z

    Mixed solvent aqueous waste of various chemical compositions constitutes a significant fraction of the total waste produced by industry in the United States. Not only does the chemical process industry create large quantities of aqueous waste, but the majority of the waste inventory at the DOE sites previously used for nuclear weapons production is mixed solvent aqueous waste. In addition, large quantities of waste are expected to be generated in the clean-up of those sites. In order to effectively treat, safely handle, and properly dispose of these wastes, accurate and comprehensive knowledge of basic thermophysical properties is essential. The goal of this work is to develop a phase equilibrium model for mixed solvent aqueous solutions containing salts. An equation of state was sought for these mixtures that (a) would require a minimum of adjustable parameters and (b) could be obtained from a available data or data that were easily measured. A model was developed to predict vapor composition and pressure given the liquid composition and temperature. It is based on the Peng-Robinson equation of state, adapted to include non-volatile and salt components. The model itself is capable of predicting the vapor-liquid equilibria of a wide variety of systems composed of water, organic solvents, salts, nonvolatile solutes, and acids or bases. The representative system o water + acetone + 2-propanol + NaNo3 was selected to test and verify the model. Vapor-liquid equilibrium and phase density measurements were performed for this system and its constituent binaries.

  10. LED ProspectsLED Prospects photometric units

    E-Print Network [OSTI]

    Pulfrey, David L.

    Illuminated by: (a) high-CRI source (b) low-CRI source EFS #12;6 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/ #12;7 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/ #12;8 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/ #12;9 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes-dot-org/ #12;10 http://www.ecse.rpi.edu/~schubert/Light-Emitting-Diodes

  11. LEDs_2LEDs_2 radiative recombination efficiency

    E-Print Network [OSTI]

    Pulfrey, David L.

    (E) lead to a peak in the light intensity. E.F. Schubert, Light-Emitting Diodes, CUP, 2006 [EFS] #12

  12. Inference of ICF implosion core mix using experimental data and theoretical mix modeling

    SciTech Connect (OSTI)

    Sherrill, Leslie Welser [Los Alamos National Laboratory; Haynes, Donald A [Los Alamos National Laboratory; Cooley, James H [Los Alamos National Laboratory; Sherrill, Manolo E [Los Alamos National Laboratory; Mancini, Roberto C [UNR; Tommasini, Riccardo [LLNL; Golovkin, Igor E [PRISM COMP. SCIENCES; Haan, Steven W [LLNL

    2009-01-01T23:59:59.000Z

    The mixing between fuel and shell materials in Inertial Confinement Fusion (lCF) implosion cores is a current topic of interest. The goal of this work was to design direct-drive ICF experiments which have varying levels of mix, and subsequently to extract information on mixing directly from the experimental data using spectroscopic techniques. The experimental design was accomplished using hydrodynamic simulations in conjunction with Haan's saturation model, which was used to predict the mix levels of candidate experimental configurations. These theoretical predictions were then compared to the mixing information which was extracted from the experimental data, and it was found that Haan's mix model predicted trends in the width of the mix layer as a function of initial shell thickness. These results contribute to an assessment of the range of validity and predictive capability of the Haan saturation model, as well as increasing confidence in the methods used to extract mixing information from experimental data.

  13. Gasification Characteristics of Coal/Biomass Mixed Fuels

    SciTech Connect (OSTI)

    Mitchell, Reginald

    2013-09-30T23:59:59.000Z

    A research project was undertaken that had the overall objective of developing the models needed to accurately predict conversion rates of coal/biomass mixtures to synthesis gas under conditions relevant to a commercially-available coal gasification system configured to co- produce electric power as well as chemicals and liquid fuels. In our efforts to accomplish this goal, experiments were performed in an entrained flow reactor in order to produce coal and biomass chars at high heating rates and temperatures, typical of the heating rates and temperatures fuel particles experience in real systems. Mixed chars derived from coal/biomass mixtures containing up to 50% biomass and the chars of the pure coal and biomass components were subjected to a matrix of reactivity tests in a pressurized thermogravimetric analyzer (TGA) in order to obtain data on mass loss rates as functions of gas temperature, pressure and composition as well as to obtain information on the variations in mass specific surface area during char conversion under kinetically-limited conditions. The experimental data were used as targets when determining the unknown parameters in the chemical reactivity and specific surface area models developed. These parameters included rate coefficients for the reactions in the reaction mechanism, enthalpies of formation and absolute entropies of adsorbed species formed on the carbonaceous surfaces, and pore structure coefficients in the model used to describe how the mass specific surface area of the char varies with conversion. So that the reactivity models can be used at high temperatures when mass transport processes impact char conversion rates, Thiele modulus – effectiveness factor relations were also derived for the reaction mechanisms developed. In addition, the reactivity model and a mode of conversion model were combined in a char-particle gasification model that includes the effects of chemical reaction and diffusion of reactive gases through particle pores and energy exchange between the particle and its environment. This char-particle gasification model is capable of predicting the average mass loss rates, sizes, apparent densities, specific surface areas, and temperatures of the char particles produced when co-firing coal and biomass to the type environments established in entrained flow gasifiers operating at high temperatures and elevated pressures. A key result of this work is the finding that the reactivities of the mixed chars were not always in between the reactivities of the pure component chars at comparable gasification conditions. Mixed char reactivity to CO{sub 2} was lower than the reactivities of both the pure Wyodak coal and pure corn stover chars to CO{sub 2}. In contrast, mixed char reactivity to H{sub 2}O was higher than the reactivities of both the pure Wyodak coal and pure corn stover chars to H{sub 2}O. This was found to be in part, a consequence of the reduced mass specific surface areas of the coal char particles formed during devolatilization when the coal and biomass particles are co-fired. The biomass particles devolatilize prior to the coal particles, impacting the temperature and the composition of the environment in which the coal particles devolatilize. This situation results in coal char particles within the mixed char that differ in specific surface area and reactivity from the coal char particles produced in the absence of the devolatilizing biomass particles. Due to presence of this “affected” coal char, it was not possible to develop a mixed char reactivity model that uses linear mixing rules to determine the reactivity of a mixed char from only the reactivities of the pure mixture components. However, it was possible to predict both mixed char specific surface area and reactivity for a wide range of fuel mixture rat os provided the specific surface area and reactivity of the affected coal char particles are known. Using the kinetic parameters determined for the Wyodak coal and corn stover chars, the model was found to adequately predict the observed conversion times a

  14. Method and apparatus for cooling high temperature superconductors with neon-nitrogen mixtures

    DOE Patents [OSTI]

    Laverman, Royce J. (South Holland, IL); Lai, Ban-Yen (Hinsdale, IL)

    1993-01-01T23:59:59.000Z

    Apparatus and methods for cooling high temperature superconducting materials (HTSC) to superconductive temperatures within the range of 27.degree. K. to 77.degree. K. using a mixed refrigerant consisting of liquefied neon and nitrogen containing up to about ten mole percent neon by contacting and surrounding the HTSC material with the mixed refrigerant so that free convection or forced flow convection heat transfer can be effected.

  15. Neutrino Mixing and Oscillations in Astrophysical Environments

    E-Print Network [OSTI]

    A. B. Balantekin

    2014-01-22T23:59:59.000Z

    A brief review of the current status of neutrino mixing and oscillations in astrophysical environments, with particular emphasis on the Sun and core-collapse supernovae, is given. Implications of the existence of sterile states which mix with the active neutrinos are discussed.

  16. Milestone M4900: Simulant Mixing Analytical Results

    SciTech Connect (OSTI)

    Kaplan, D.I.

    2001-07-26T23:59:59.000Z

    This report addresses Milestone M4900, ''Simulant Mixing Sample Analysis Results,'' and contains the data generated during the ''Mixing of Process Heels, Process Solutions, and Recycle Streams: Small-Scale Simulant'' task. The Task Technical and Quality Assurance Plan for this task is BNF-003-98-0079A. A report with a narrative description and discussion of the data will be issued separately.

  17. Adaptive wavelet deconvolution for strongly mixing sequences

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Adaptive wavelet deconvolution for strongly mixing sequences Christophe Chesneau Abstract square error over Besov balls, we explore the performances of two wavelet estimators: a standard linear, Strongly mixing, Adap- tivity, Wavelets, Hard thresholding. AMS 2000 Subject Classifications: 62G07, 62G20

  18. Neutrino mixing and oscillations in astrophysical environments

    SciTech Connect (OSTI)

    Balantekin, A. B. [Physics Department, University of Wisconsin, Madison WI 53706 (United States)

    2014-05-02T23:59:59.000Z

    A brief review of the current status of neutrino mixing and oscillations in astrophysical environments, with particular emphasis on the Sun and core-collapse supernovae, is given. Implications of the existence of sterile states which mix with the active neutrinos are discussed.

  19. Predictions From High Scale Mixing Unification Hypothesis

    E-Print Network [OSTI]

    Srivastava, Rahul

    2015-01-01T23:59:59.000Z

    Starting with 'High Scale Mixing Unification' hypothesis, we investigate the renormalization group evolution of mixing parameters and masses for both Dirac and Majorana type neutrinos. Following this hypothesis, the PMNS mixing parameters are taken to be identical to the CKM ones at a unifying high scale. Then, they are evolved to a low scale using MSSM renormalization-group equations. For both type of neutrinos, the renormalization group evolution 'naturally' results in a non-zero and small value of leptonic mixing angle $\\theta_{13}$. One of the important predictions of this analysis is that, in both cases, the mixing angle $\\theta_{23}$ turns out to be non-maximal for most of the parameter range. We also elaborate on the important differences between Dirac and Majorana neutrinos within our framework and how to experimentally distinguish between the two scenarios. Furthermore, for both cases, we also derive constraints on the allowed parameter range for the SUSY breaking and unification scales, for which th...

  20. Mixed waste characterization, treatment & disposal focus area

    SciTech Connect (OSTI)

    NONE

    1996-08-01T23:59:59.000Z

    The mission of the Mixed Waste Characterization, Treatment, and Disposal Focus Area (referred to as the Mixed Waste Focus Area or MWFA) is to provide treatment systems capable of treating DOE`s mixed waste in partnership with users, and with continual participation of stakeholders, tribal governments, and regulators. The MWFA deals with the problem of eliminating mixed waste from current and future storage in the DOE complex. Mixed waste is waste that contains both hazardous chemical components, subject to the requirements of the Resource Conservation and Recovery Act (RCRA), and radioactive components, subject to the requirements of the Atomic Energy Act. The radioactive components include transuranic (TRU) and low-level waste (LLW). TRU waste primarily comes from the reprocessing of spent fuel and the use of plutonium in the fabrication of nuclear weapons. LLW includes radioactive waste other than uranium mill tailings, TRU, and high-level waste, including spent fuel.

  1. Thin films of mixed metal compounds

    DOE Patents [OSTI]

    Mickelsen, R.A.; Chen, W.S.

    1985-06-11T23:59:59.000Z

    Disclosed is a thin film heterojunction solar cell, said heterojunction comprising a p-type I-III-IV[sub 2] chalcopyrite substrate and an overlying layer of an n-type ternary mixed metal compound wherein said ternary mixed metal compound is applied to said substrate by introducing the vapor of a first metal compound to a vessel containing said substrate from a first vapor source while simultaneously introducing a vapor of a second metal compound from a second vapor source of said vessel, said first and second metals comprising the metal components of said mixed metal compound; independently controlling the vaporization rate of said first and second vapor sources; reducing the mean free path between vapor particles in said vessel, said gas being present in an amount sufficient to induce homogeneity of said vapor mixture; and depositing said mixed metal compound on said substrate in the form of a uniform composition polycrystalline mixed metal compound. 5 figs.

  2. Second Law Analysis of Constant Temperature Diesel Combustion

    SciTech Connect (OSTI)

    Druecke, Dr. Ben [University of Wisconsin; Foster, Prof. Dave [University of Wisconsin; Klein, Prof. Sandy [University of Wisconsin; Daw, C Stuart [ORNL; Chakravarthy, Veerathu K [ORNL; Graves, Ronald L [ORNL

    2006-01-01T23:59:59.000Z

    The results from a second law analysis of a constant temperature diesel combustion process are presented and show that this process is not significantly more reversible than conventional combustion. In addition to quantifying the total availability destruction in combustion, the magnitudes of the combustion irreversibilities attributable to each irreversible subprocess (mixing, oxidation and internal heat transfer) were determined. The primary contributor to combustion irreversibilities is the thermal interaction of reacting and non-reacting species during the oxidation and internal thermal energy transfer subprocesses. Increasing combustion temperature significantly decreases availability destruction by making the oxidation and internal thermal energy transfer processes more reversible. While increasing combustion temperature decreases combustion irreversibility, it also results in an increase in exhaust temperature. A tradeoff exists between large availability destruction at low combustion temperatures and large amounts of availability discarded in the exhaust at high combustion temperatures. The optimum amount of work was found to occur for a combustion temperature of approximately 1600 K.

  3. Absorber Materials at Room and Cryogenic Temperatures

    SciTech Connect (OSTI)

    F. Marhauser, T.S. Elliott, A.T. Wu, E.P. Chojnacki, E. Savrun

    2011-09-01T23:59:59.000Z

    We recently reported on investigations of RF absorber materials at cryogenic temperatures conducted at Jefferson Laboratory (JLab). The work was initiated to find a replacement material for the 2 Kelvin low power waveguide Higher Order Mode (HOM) absorbers employed within the original cavity cryomodules of the Continuous Electron Beam Accelerator Facility (CEBAF). This effort eventually led to suitable candidates as reported in this paper. Furthermore, though constrained by small funds for labor and resources, we have analyzed a variety of lossy ceramic materials, several of which could be usable as HOM absorbers for both normal conducting and superconducting RF structures, e.g. as loads in cavity waveguides and beam tubes either at room or cryogenic temperatures and, depending on cooling measures, low to high operational power levels.

  4. Correlation of Beam Electron and LED Signal Losses under Irradiation and Long-term Recovery of Lead Tungstate Crystals

    E-Print Network [OSTI]

    V. A. Batarin; J. Butler; A. M. Davidenko; A. A. Derevschikov; Y. M. Goncharenko; V. N. Grishin; V. A. Kachanov; A. S. Konstantinov; V. I. Kravtsov; Y. Kubota; V. S. Lukanin; Y. A. Matulenko; Y. M. Melnick; A. P. Meschanin; N. E. Mikhalin; N. G. Minaev; V. V. Mochalov; D. A. Morozov; L. V. Nogach; A. V. Ryazantsev; P. A. Semenov; V. K. Semenov; K. E. Shestermanov; L. F. Soloviev; S. Stone; A. V. Uzunian; A. N. Vasiliev; A. E. Yakutin; J. Yarba

    2005-04-13T23:59:59.000Z

    Radiation damage in lead tungstate crystals reduces their transparency. The calibration that relates the amount of light detected in such crystals to incident energy of photons or electrons is of paramount importance to maintaining the energy resolution the detection system. We report on tests of lead tungstate crystals, read out by photomultiplier tubes, exposed to irradiation by monoenergetic electron or pion beams. The beam electrons themselves were used to measure the scintillation light output, and a blue light emitting diode (LED) was used to track variations of crystals transparency. We report on the correlation of the LED measurement with radiation damage by the beams and also show that it can accurately monitor the crystals recovery from such damage.

  5. Method and apparatus for low temperature destruction of halogenated hydrocarbons

    DOE Patents [OSTI]

    Reagen, William Kevin (Stillwater, MN); Janikowski, Stuart Kevin (Idaho Falls, ID)

    1999-01-01T23:59:59.000Z

    A method and apparatus for decomposing halogenated hydrocarbons are provided. The halogenated hydrocarbon is mixed with solvating agents and maintained in a predetermined atmosphere and at a predetermined temperature. The mixture is contacted with recyclable reactive material for chemically reacting with the recyclable material to create dehalogenated hydrocarbons and halogenated inorganic compounds. A feature of the invention is that the process enables low temperature destruction of halogenated hydrocarbons.

  6. Assessing the Performance of LED-Based Flashlights Available in the Kenyan Off-Grid Lighting Market

    SciTech Connect (OSTI)

    Tracy, Jennifer; Jacobson, Arne; Mills, Evan

    2010-03-02T23:59:59.000Z

    Low cost rechargeable flashlights that use LED technology are increasingly available in African markets. While LED technology holds promise to provide affordable, high quality lighting services, the widespread dissemination of low quality products may make it difficult to realize this potential. This study includes performance results for three brands of commonly available LED flashlights that were purchased in Kenya in 2009. The performance of the flashlights was evaluated by testing five units for each of the three brands. The tests included measurements of battery capacity, time required to charge the battery, maximum illuminance at one meter, operation time and lux-hours from a fully charged battery, light distribution, and color rendering. All flashlights tested performed well below the manufacturers? rated specifications; the measured battery capacity was 30-50percent lower than the rated capacity and the time required to fully charge the battery was 6-25percent greater than the rated time requirement. Our analysis further shows that within each brand there is considerable variability in each performance indicator. The five samples within a single brand varied from each other by as much as 22percent for battery capacity measurements, 3.6percent for the number of hours required for a full charge, 23percent for maximum initial lux, 38percent for run time, 11percent for light distribution and by as much as 200percent for color rendering. Results obtained are useful for creating a framework for quality assurance of off-grid LED products and will be valuable for informing consumers, distributors and product manufacturers about product performance.

  7. Demonstration Assessment of Light Emitting Diode (LED) Commercial Garage Lights In the Providence Portland Medical Center, Portland, Oregon

    SciTech Connect (OSTI)

    Ton, My K.; Richman, Eric E.; Gilbride, Theresa L.

    2008-11-11T23:59:59.000Z

    This U.S. Department of Energy GATEWAY Demonstration project studied the applicability of light-emitting diode (LED) luminaires for commercial parking garage applications. High-pressure sodium (HPS) area luminaires were replaced with new LED area luminaires. The project was supported under the U.S. Department of Energy (DOE) Solid State Lighting Program. Other participants in the demonstration project included Providence Portland Medical Center in Portland, Oregon, the Energy Trust of Oregon, and Lighting Sciences Group (LSG) Inc. Pacific Northwest National Laboratory (PNNL) conducted the measurements and analysis of the results. PNNL manages GATEWAY demonstrations for DOE and represents their perspective in the conduct of the work. Quantitative and qualitative measurements of light and electrical power were taken at the site for both HPS and LED light sources. Economic costs were estimated and garage users’ responses to the new light sources were gauged with a survey. Six LED luminaires were installed in the below-ground parking level A, replacing six existing 150W HPS lamps spread out over two rows of parking spaces. Illuminance measurements were taken at floor level approximately every 4 ft on a 60-ft x 40-ft grid to measure light output of these LED luminaires which were termed the “Version 1” luminaires. PNNL conducted power measurements of the circuit in the garage to which the 6 luminaires were connected and determined that they drew an average of 82 W per lamp. An improved LED luminaire, Version 2, was installed in Level B of the parking garage. Illuminance measurements were not made of this second luminaire on site due to higher traffic conditions, but photometric measurements of this lamp and Version 1 were made in an independent testing laboratory and power usage for Version 2 was also measured. Version 1 was found to produce 3600 lumens and Version 2 was found to produce 4700 lumens of light and to consume 78 Watts. Maximum and minimum light levels were measured for the HPS and LED Version 1 luminaires and projected for the Version 2 luminaires. Maximum light levels were 23.51 foot candles, 20.54 fc, and 26.7 fc respectively and minimum light levels were 1.49 fc, 1.45 fc, and 1.88 fc. These results indicate very similar or even slightly higher light levels produced by the LED lamps, despite the higher lumen output of the HPS lamp. The LED lamps provide higher luminaire efficacy because all of the light is directed down and out. None of it is “lost” in the fixture. Also the HPS luminaire had poorly designed optics and a plastic covering that tended to get dirty and cracked, further decreasing the realized light output.[is this an accurate way to say this?] Consumer perceptions of the Version 2 LED were collected via a written survey form given to maintenance and security personnel. More than half felt the LED luminaires provided more light than the HPS lamps and a majority expressed a preference for the new lamps when viewing the relamped area through a security camera. Respondents commented that the LED luminaires were less glary, created less shadows, had a positive impact on visibility, and improved the overall appearance of the area. PNNL conducted an economic analysis and found that the Version 1 lamp produced annual energy savings of 955 kWh and energy cost savings of $76.39 per lamp at electricity rates of 6.5 cents per kWh and $105.03 at 11 cents per kWh. PNNL found that the Version 2 lamp produced annual energy savings of 991 kWh and energy cost savings of $79.26 per lamp at electricity rates of 6.5 cents per kWh and $108.98 at 11 cents per kWh. PNNL also calculated simple payback and found that Version 1 showed paybacks of 5.4 yrs at 6.5c/kWh and 4.1 yrs at 11c/kWh while Version 2 showed paybacks of 5.2 yrs at 6.5c/kWh and 3.9 yrs at 11c/kWh.

  8. The photocatalysis of Bi{sub 2}MoO{sub 6} under the irradiation of blue LED

    SciTech Connect (OSTI)

    Sun, Yuanyuan; Wang, Wenzhong, E-mail: wzwang@mail.sic.ac.cn; Zhang, Ling; Sun, Songmei

    2013-10-15T23:59:59.000Z

    Graphical abstract: - Highlights: • ·OH trap and hole sink were involved to investigate the active radicals. • Holes play a more important role in the degradation of RhB. • The ·OH were related to the decomposition of phenol. • The ·O{sub 2}-played a leading role in the photodegradation of phenol. • Blue LED is competitive and promising alternative for the future application. - Abstract: Bi{sub 2}MoO{sub 6} has been reported as a promising photocatalyst in wastewater treatment. The active radicals generated over the Bi{sub 2}MoO{sub 6} during the photocatalytic process were thought to be hydroxyl radical (·OH) but have not been proved. Herein, Bi{sub 2}MoO{sub 6} with nanoplate like morphology was synthesized and its photocatalytic performances in the degradation of rhodamine B (RhB) and phenol as colored and colorless model pollutants respectively were evaluated under the irradiation of blue light emitting diode (LED). The tert-butyl alcohol (TBA) as a ·OH trap and ethylene diamine tetraacetic acid (EDTA) as a hole sink were involved to investigate the main active groups that are generated on Bi{sub 2}MoO{sub 6} and function during the photodegradation of RhB and phenol. In addition, it is a competitive and promising alternative plan to use blue LED as light source for the future practical application in environmental remediation.

  9. Method for low temperature preparation of a noble metal alloy

    DOE Patents [OSTI]

    Even, Jr., William R. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    A method for producing fine, essentially contamination free, noble metal alloys is disclosed. The alloys comprise particles in a size range of 5 to 500 nm. The method comprises 1. A method for preparing a noble metal alloy at low temperature, the method comprising the steps of forming solution of organometallic compounds by dissolving the compounds into a quantity of a compatible solvent medium capable of solvating the organometallic, mixing a portion of each solution to provide a desired molarity ratio of ions in the mixed solution, adding a support material, rapidly quenching droplets of the mixed solution to initiate a solute-solvent phase separation as the solvent freezes, removing said liquid cryogen, collecting and freezing drying the frozen droplets to produce a dry powder, and finally reducing the powder to a metal by flowing dry hydrogen over the powder while warming the powder to a temperature of about 150.degree. C.

  10. Synthesis and luminescence properties of rare earth activated phosphors for near UV-emitting LEDs for efficacious generation of white light

    E-Print Network [OSTI]

    Han, Jinkyu

    2013-01-01T23:59:59.000Z

    LEDs is the significant current droop at high current, whicha binning problem and current droop problems [9]. Thus, theinvestigated due to less current droop and improved binning

  11. Data Sheet Fujitsu Display B24T-7 LED proGREEN Displays Page 1 / 4 http://www.fujitsu.com/fts/displays

    E-Print Network [OSTI]

    Ott, Albrecht

    , EN 60950, RoHS, WEEE, IT-Eco-Declaration Model B24T- LED Germany TÜV GS Russia GOST USA/Canada FCC

  12. Data Sheet Fujitsu Display B22T-7 LED proGREEN Displays Page 1 / 4 http://www.fujitsu.com/fts/displays

    E-Print Network [OSTI]

    Ott, Albrecht

    , EN 60950, RoHS, WEEE, IT-Eco-Declaration Model B22T-7 LED Germany TÜV GS Russia GOST USA/Canada FCC

  13. Asphalt Pavement Aging and TemperatureAsphalt Pavement Aging and Temperature Dependent Properties using a FunctionallyDependent Properties using a Functionally

    E-Print Network [OSTI]

    Paulino, Glaucio H.

    Asphalt Pavement Aging and TemperatureAsphalt Pavement Aging and Temperature Dependent Properties Analysis Time Integration Analysis Application Examples: Asphalt Pavement Summary and Conclusions #12) ­ Large fraction produced as hot-mix asphalt (HMA) ­ Most common form of pavement surfacing material (96

  14. Cooled, temperature controlled electrometer

    DOE Patents [OSTI]

    Morgan, John P. (Idaho Falls, ID)

    1992-01-01T23:59:59.000Z

    A cooled, temperature controlled electrometer for the measurement of small currents. The device employs a thermal transfer system to remove heat from the electrometer circuit and its environment and dissipate it to the external environment by means of a heat sink. The operation of the thermal transfer system is governed by a temperature regulation circuit which activates the thermal transfer system when the temperature of the electrometer circuit and its environment exceeds a level previously inputted to the external variable temperature control circuit. The variable temperature control circuit functions as subpart of the temperature control circuit. To provide temperature stability and uniformity, the electrometer circuit is enclosed by an insulated housing.

  15. Cooled, temperature controlled electrometer

    DOE Patents [OSTI]

    Morgan, John P.

    1992-08-04T23:59:59.000Z

    A cooled, temperature controlled electrometer for the measurement of small currents. The device employs a thermal transfer system to remove heat from the electrometer circuit and its environment and dissipate it to the external environment by means of a heat sink. The operation of the thermal transfer system is governed by a temperature regulation circuit which activates the thermal transfer system when the temperature of the electrometer circuit and its environment exceeds a level previously inputted to the external variable temperature control circuit. The variable temperature control circuit functions as subpart of the temperature control circuit. To provide temperature stability and uniformity, the electrometer circuit is enclosed by an insulated housing.

  16. Mixed oxygen ion/electron-conducting ceramics for oxygen separation

    SciTech Connect (OSTI)

    Stevenson, J.W.; Armstrong, B.L.; Armstrong, T.R.; Bates, J.L.; Pederson, L.R.; Weber, W.J.

    1995-05-01T23:59:59.000Z

    Solid mixed-conducting electrolytes in the series La{sub l-x}A{sub x}Co{sub l-y}Fe{sub y}O{sub 3-{delta}} (A = Sr,Ca,Ba) are potentially useful as passive membranes to separate high purity oxygen from air and as cathodes in fuel cells. All of the compositions studied exhibited very high electrical conductivities. At lower temperatures, conductivities increased with increasing temperature, characterized by activation energies of 0.05 to 0.16 eV that are consistent with a small polaron (localized electronic carrier) conduction mechanism. At higher temperatures, electronic conductivities tended to decrease with increasing temperature, which is attributed to decreased electronic carrier populations associated with lattice oxygen loss. Oxygen ion conductivities were higher than that of yttria stabilized zirconia and increased with the cobalt content and also increased with the extent of divalent A-site substitution. Thermogravimetric studies were conducted to establish the extent of oxygen vacancy formation as a function of temperature, oxygen partial pressure, and composition. These vacancy populations strongly depend on the extent of A-site substitution. Passive oxygen permeation rates were established for each of the compositions as a function of temperature and oxygen partial pressure gradient. For 2.5 mm thick membranes in an oxygen vs nitrogen partial pressure gradient, oxygen fluxes at 900 C ranged from approximately 0.3 sccm/cm{sup 2} for compositions high in iron and with low amounts of strontium A-site substitution to approximately 0.8 sccm/cm{sup 2} for compositions high in cobalt and strontium. A-site substitution with calcium instead of strontium resulted in substantially lower fluxes.

  17. Fast mix table construction for material discretization

    SciTech Connect (OSTI)

    Johnson, S. R. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

    2013-07-01T23:59:59.000Z

    An effective hybrid Monte Carlo-deterministic implementation typically requires the approximation of a continuous geometry description with a discretized piecewise-constant material field. The inherent geometry discretization error can be reduced somewhat by using material mixing, where multiple materials inside a discrete mesh voxel are homogenized. Material mixing requires the construction of a 'mix table,' which stores the volume fractions in every mixture so that multiple voxels with similar compositions can reference the same mixture. Mix table construction is a potentially expensive serial operation for large problems with many materials and voxels. We formulate an efficient algorithm to construct a sparse mix table in O(number of voxels x log number of mixtures) time. The new algorithm is implemented in ADVANTG and used to discretize continuous geometries onto a structured Cartesian grid. When applied to an end-of-life MCNP model of the High Flux Isotope Reactor with 270 distinct materials, the new method improves the material mixing time by a factor of 100 compared to a naive mix table implementation. (authors)

  18. $B_d-\\bar{B}_d$ mixing vs. $B_s-\\bar{B}_s$ mixing with the anomalous $Wtb$ couplings

    E-Print Network [OSTI]

    Jong Phil Lee; Kang Young Lee

    2008-09-29T23:59:59.000Z

    We explore the effects of the anomalous $tbW$ couplings on the $\\bd$ mixing and recently measured $\\bs$ mixing. The combined analysis of mixings via box diagrams with penguin decays provides strong constraints on the anomalous top quark couplings. We find the bound from the $\\bd$ mixing data is stronger than that from the $\\bs$ mixing.

  19. Absence of Thermophoretic Flow in Relativistic Heavy-Ion Collisions as an Indicator for the Absence of a Mixed Phase

    E-Print Network [OSTI]

    Markus H. Thoma

    2002-04-30T23:59:59.000Z

    If a quark-gluon plasma is formed in relativistic heavy-ion collisions, there may or may not be a mixed phase of quarks, gluons and hadronic clusters when the critical temperature is reached in the expansion of the fireball. If there is a temperature gradient in the fireball, the hadronic clusters, embedded in the heat bath of quarks and gluons, are subjected to a thermophoretic force. It is shown that even for small temperature gradients and short lifetimes of the mixed phase, thermophoresis would lead to a flow essentially stronger than the observed one. The absence of this strong flow provides support for a rapid or sudden hadronization mechanism without a mixed phase.

  20. Ultra High Temperature Rapid Thermal Annealing of GaN

    SciTech Connect (OSTI)

    Cao, X.A.; Fu, M.; Han, J.; Pearton, S.J.; Rieger, D.J.; Sekhar, J.A.; Shul, R.J.; Singh, R.K.; Wilson, R.G.; Zolper, J.C.

    1998-11-20T23:59:59.000Z

    All of the major acceptor (Mg, C, Be) and donor (Si, S, Se and Te) dopants have been implanted into GaN films grown on A1203 substrates. Annealing was performed at 1100- 1500 C, using AIN encapsulation. Activation percentages of >90Y0 were obtained for Si+ implantation annealed at 1400 C, while higher temperatures led to a decrease in both carrier concentration and electron mobility. No measurable redistribution of any of the implanted dopants was observed at 1450 C.