Science.gov

Sample records for high efficient facility

  1. High efficiency waste to energy facility -- Pilot plant design

    SciTech Connect

    Orita, Norihiko; Kawahara, Yuuzou; Takahashi, Kazuyoshi; Yamauchi, Toru; Hosoda, Takuo

    1998-07-01

    Waste To Energy facilities are commonly acceptable to the environment and give benefits in two main areas: one is a hygienic waste disposal and another is waste heat energy recovery to save fossil fuel consumption. Recovered energy is used for electricity supply, and it is required to increase the efficiency of refuse to electric energy conversion, and to spread the plant construction throughout the country of Japan, by the government. The national project started in 1992, and pilot plant design details were established in 1995. The objective of the project is to get 30% of energy conversion efficiency through the measure by raising the steam temperature and pressure to 500 C and 9.8 MPa respectively. The pilot plant is operating under the design conditions, which verify the success of applied technologies. This paper describes key technologies which were used to design the refuse burning boiler, which generates the highest steam temperature and pressure steam.

  2. Low turbulence/high efficiency cyclone separators: Facility qualification results

    SciTech Connect

    Razgaitis, R.; Paul, D.D.; Bioarski, A.A.; Jordan, H. ); Brodkey, R.S.; Munson-McGee, M. . Dept. of Chemical Engineering)

    1985-01-01

    The objective of this work is to experimentally investigate the near-wall turbulent flow-fields characteristic of cyclone separators in order to determine the influence of wall-originating turbulence on the separation of fine particles. In particular, seven turbulence suppression concepts will be evaluated with reference to a well-established baseline condition. Concepts which appear attractive will be studied and characterized in more detail. The work accomplished to date is principally the design, construction, and qualification of two of the facilities that will be used to study the various concepts of turbulence suppression. The qualification of the primary facility, the Cyclonic Wind Tunnel (CWT), has required the development and adaptation of laser Doppler velocimetry (LDV) to perform simultaneous two-dimensional turbulence measurements in a highly swirling flow. A companion facility to the CWT is the Curvilinear Boundary Layer (CBL) apparatus. The purpose of the CBL is to provide a thick, visually-observable near-wall flow region under dynamically similar conditions to the CWT to that a physical understanding of the turbulence suppression process can be obtained. 9 refs., 15 figs.

  3. A facile grating approach towards broadband, wide-angle and high-efficiency holographic metasurfaces.

    PubMed

    Deng, Zi-Lan; Zhang, Shuang; Wang, Guo Ping

    2016-01-21

    We analytically show that an incident light can be almost completely diffracted into the -1(st) order in wide-angle and broadband by suitably designed thin metallic nano-gratings with simple rectangular cross sections. Such extraordinary optical diffraction results from the excitation of localized cavity modes and exists even when the grating period is modulated in a broad range. By modulating the period with binary holography techniques, we can shape an incident wave into arbitrary wavefronts with near-unity conversion efficiencies. To show the efficacy of this approach, we demonstrate three reflection-type metasurfaces for achieving near-complete conversions from a Gaussian beam into a focused beam, Bessel beam, and vortex beam, respectively, with the complete suppression of the undesired specular reflection. Our findings provide a facile approach to build arbitrary wavefront-shaping metasurfaces with wide-angle, broadband, and high efficiency performance. PMID:26689542

  4. Facile and high-efficient immobilization of histidine-tagged multimeric protein G on magnetic nanoparticles

    PubMed Central

    2014-01-01

    This work reports the high-efficient and one-step immobilization of multimeric protein G on magnetic nanoparticles. The histidine-tagged (His-tag) recombinant multimeric protein G was overexpressed in Escherichia coli BL21 by the repeated linking of protein G monomers with a flexible linker. High-efficient immobilization on magnetic nanoparticles was demonstrated by two different preparation methods through the amino-silane and chloro-silane functionalization on silica-coated magnetic nanoparticles. Three kinds of multimeric protein G such as His-tag monomer, dimer, and trimer were tested for immobilization efficiency. For these tests, bicinchoninic acid (BCA) assay was employed to determine the amount of immobilized His-tag multimeric protein G. The result showed that the immobilization efficiency of the His-tag multimeric protein G of the monomer, dimer, and trimer was increased with the use of chloro-silane-functionalized magnetic nanoparticles in the range of 98% to 99%, rather than the use of amino-silane-functionalized magnetic nanoparticles in the range of 55% to 77%, respectively. PMID:25593554

  5. High efficiency gratings for beam steering on the National Ignition Facility (NIF) laser

    SciTech Connect

    Perry, M.D.; Dixit, S.N.; Shore, B.W.; Boyd, R.D.; Britten, J.A.; Powell, H.T.

    1995-05-26

    The design of the National Ignition Facility (NIF) is based on conversion of 1.05 {mu}m wavelength light (1{omega}) into third harmonic light (3{omega}) by passage through KDP frequency conversion crystals. It is important for proper coupling of radiation into the targets that the final beam impinging upon the target should have little 1{omega} or 2{omega} light. It is also desirable to avoid direct line-of sight for neutrons between the target and the KDP crystals, in order to prevent damage. These issues can be overcome by employing diffraction gratings immediately before the final NIF focusing lens to direct the 3{omega} beam to the target. A single grating design is highly dispersive, and may introduce intolerable divergence into the beam. In order to overcome this limitation, we propose to use a grating pair. This will provide transverse offset of the beam and eliminate the dispersion while offering several other advantages.

  6. Improving a high-efficiency, gated spectrometer for x-ray Thomson scattering experiments at the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Döppner, T.; Kraus, D.; Neumayer, P.; Bachmann, B.; Emig, J.; Falcone, R. W.; Fletcher, L. B.; Hardy, M.; Kalantar, D. H.; Kritcher, A. L.; Landen, O. L.; Ma, T.; Saunders, A. M.; Wood, R. D.

    2016-11-01

    We are developing x-ray Thomson scattering for applications in implosion experiments at the National Ignition Facility. In particular we have designed and fielded MACS, a high-efficiency, gated x-ray spectrometer at 7.5-10 keV [T. Döppner et al., Rev. Sci. Instrum. 85, 11D617 (2014)]. Here we report on two new Bragg crystals based on Highly Oriented Pyrolytic Graphite (HOPG), a flat crystal and a dual-section cylindrically curved crystal. We have performed in situ calibration measurements using a brass foil target, and we used the flat HOPG crystal to measure Mo K-shell emission at 18 keV in 2nd order diffraction. Such high photon energy line emission will be required to penetrate and probe ultra-high-density plasmas or plasmas of mid-Z elements.

  7. Facile and Scalable Preparation of Graphene Oxide-Based Magnetic Hybrids for Fast and Highly Efficient Removal of Organic Dyes

    NASA Astrophysics Data System (ADS)

    Jiao, Tifeng; Liu, Yazhou; Wu, Yitian; Zhang, Qingrui; Yan, Xuehai; Gao, Faming; Bauer, Adam J. P.; Liu, Jianzhao; Zeng, Tingying; Li, Bingbing

    2015-07-01

    This study reports the facile preparation and the dye removal efficiency of nanohybrids composed of graphene oxide (GO) and Fe3O4 nanoparticles with various geometrical structures. In comparison to previously reported GO/Fe3O4 composites prepared through the one-pot, in situ deposition of Fe3O4 nanoparticles, the GO/Fe3O4 nanohybrids reported here were obtained by taking advantage of the physical affinities between sulfonated GO and Fe3O4 nanoparticles, which allows tuning the dimensions and geometries of Fe3O4 nanoparticles in order to decrease their contact area with GO, while still maintaining the magnetic properties of the nanohybrids for easy separation and adsorbent recycling. Both the as-prepared and regenerated nanohybrids demonstrate a nearly 100% removal rate for methylene blue and an impressively high removal rate for Rhodamine B. This study provides new insights into the facile and controllable industrial scale fabrication of safe and highly efficient GO-based adsorbents for dye or other organic pollutants in a wide range of environmental-related applications.

  8. Facile and Scalable Preparation of Graphene Oxide-Based Magnetic Hybrids for Fast and Highly Efficient Removal of Organic Dyes

    PubMed Central

    Jiao, Tifeng; Liu, Yazhou; Wu, Yitian; Zhang, Qingrui; Yan, Xuehai; Gao, Faming; Bauer, Adam J. P.; Liu, Jianzhao; Zeng, Tingying; Li, Bingbing

    2015-01-01

    This study reports the facile preparation and the dye removal efficiency of nanohybrids composed of graphene oxide (GO) and Fe3O4 nanoparticles with various geometrical structures. In comparison to previously reported GO/Fe3O4 composites prepared through the one-pot, in situ deposition of Fe3O4 nanoparticles, the GO/Fe3O4 nanohybrids reported here were obtained by taking advantage of the physical affinities between sulfonated GO and Fe3O4 nanoparticles, which allows tuning the dimensions and geometries of Fe3O4 nanoparticles in order to decrease their contact area with GO, while still maintaining the magnetic properties of the nanohybrids for easy separation and adsorbent recycling. Both the as-prepared and regenerated nanohybrids demonstrate a nearly 100% removal rate for methylene blue and an impressively high removal rate for Rhodamine B. This study provides new insights into the facile and controllable industrial scale fabrication of safe and highly efficient GO-based adsorbents for dye or other organic pollutants in a wide range of environmental-related applications. PMID:26220847

  9. Qualification of a high-efficiency, gated spectrometer for x-ray Thomson scattering on the National Ignition Facility

    SciTech Connect

    Döppner, T.; Kritcher, A. L.; Bachmann, B.; Burns, S.; Hawreliak, J.; House, A.; Landen, O. L.; LePape, S.; Ma, T.; Pak, A.; Swift, D.; Neumayer, P.; Kraus, D.; Falcone, R. W.; Glenzer, S. H.

    2014-11-15

    We have designed, built, and successfully fielded a highly efficient and gated Bragg crystal spectrometer for x-ray Thomson scattering measurements on the National Ignition Facility (NIF). It utilizes a cylindrically curved Highly Oriented Pyrolytic Graphite crystal. Its spectral range of 7.4–10 keV is optimized for scattering experiments using a Zn He-α x-ray probe at 9.0 keV or Mo K-shell line emission around 18 keV in second diffraction order. The spectrometer has been designed as a diagnostic instrument manipulator-based instrument for the NIF target chamber at the Lawrence Livermore National Laboratory, USA. Here, we report on details of the spectrometer snout, its novel debris shield configuration and an in situ spectral calibration experiment with a Brass foil target, which demonstrated a spectral resolution of E/ΔE = 220 at 9.8 keV.

  10. Facile synthesis of highly efficient and recyclable magnetic solid acid from biomass waste.

    PubMed

    Liu, Wu-Jun; Tian, Ke; Jiang, Hong; Yu, Han-Qing

    2013-01-01

    In this work, sawdust, a biomass waste, is converted into a magnetic porous carbonaceous (MPC) solid acid catalyst by an integrated fast pyrolysis-sulfonation process. The resultant magnetic solid acid has a porous structure with high surface area of 296.4 m(2) g(-1), which can be attributed to the catalytic effect of Fe. The catalytic activity and recyclability of the solid acid catalyst are evaluated during three typical acid-catalyzed reactions: esterification, dehydration, and hydrolysis. The favorable catalytic performance in all three reactions is attributed to the acid's high strength with 2.57 mmol g(-1) of total acid sites. Moreover, the solid acid can be reused five times without a noticeable decrease in catalytic activity, indicating the stability of the porous carbon (PC)-sulfonic acid group structure. The findings in the present work offer effective alternatives for environmentally friendly utilization of abundant biomass waste. PMID:23939253

  11. Facile synthesis of highly efficient and recyclable magnetic solid acid from biomass waste

    NASA Astrophysics Data System (ADS)

    Liu, Wu-Jun; Tian, Ke; Jiang, Hong; Yu, Han-Qing

    2013-08-01

    In this work, sawdust, a biomass waste, is converted into a magnetic porous carbonaceous (MPC) solid acid catalyst by an integrated fast pyrolysis-sulfonation process. The resultant magnetic solid acid has a porous structure with high surface area of 296.4 m2 g-1, which can be attributed to the catalytic effect of Fe. The catalytic activity and recyclability of the solid acid catalyst are evaluated during three typical acid-catalyzed reactions: esterification, dehydration, and hydrolysis. The favorable catalytic performance in all three reactions is attributed to the acid's high strength with 2.57 mmol g-1 of total acid sites. Moreover, the solid acid can be reused five times without a noticeable decrease in catalytic activity, indicating the stability of the porous carbon (PC)-sulfonic acid group structure. The findings in the present work offer effective alternatives for environmentally friendly utilization of abundant biomass waste.

  12. Facile synthesis of highly efficient and recyclable magnetic solid acid from biomass waste

    PubMed Central

    Liu, Wu-Jun; Tian, Ke; Jiang, Hong; Yu, Han-Qing

    2013-01-01

    In this work, sawdust, a biomass waste, is converted into a magnetic porous carbonaceous (MPC) solid acid catalyst by an integrated fast pyrolysis–sulfonation process. The resultant magnetic solid acid has a porous structure with high surface area of 296.4 m2 g−1, which can be attributed to the catalytic effect of Fe. The catalytic activity and recyclability of the solid acid catalyst are evaluated during three typical acid-catalyzed reactions: esterification, dehydration, and hydrolysis. The favorable catalytic performance in all three reactions is attributed to the acid's high strength with 2.57 mmol g−1 of total acid sites. Moreover, the solid acid can be reused five times without a noticeable decrease in catalytic activity, indicating the stability of the porous carbon (PC)–sulfonic acid group structure. The findings in the present work offer effective alternatives for environmentally friendly utilization of abundant biomass waste. PMID:23939253

  13. High energy forming facility

    NASA Technical Reports Server (NTRS)

    Ciurlionis, B.

    1967-01-01

    Watertight, high-explosive forming facility, 25 feet in diameter and 15 feet deep, withstands repeated explosions of 10 pounds of TNT equivalent. The shell is fabricated of high strength steel and allows various structural elements to deform or move elastically and independently while retaining structural integrity.

  14. Nanofluidic crystal: a facile, high-efficiency and high-power-density scaling up scheme for energy harvesting based on nanofluidic reverse electrodialysis.

    PubMed

    Ouyang, Wei; Wang, Wei; Zhang, Haixia; Wu, Wengang; Li, Zhihong

    2013-08-30

    The great advances in nanotechnology call for advances in miniaturized power sources for micro/nano-scale systems. Nanofluidic channels have received great attention as promising high-power-density substitutes for ion exchange membranes for use in energy harvesting from ambient ionic concentration gradient, namely reverse electrodialysis. This paper proposes the nanofluidic crystal (NFC), of packed nanoparticles in micro-meter-sized confined space, as a facile, high-efficiency and high-power-density scaling-up scheme for energy harvesting by nanofluidic reverse electrodialysis (NRED). Obtained from the self-assembly of nanoparticles in a micropore, the NFC forms an ion-selective network with enormous nanochannels due to electrical double-layer overlap in the nanoparticle interstices. As a proof-of-concept demonstration, a maximum efficiency of 42.3 ± 1.84%, a maximum power density of 2.82 ± 0.22 W m(-2), and a maximum output power of 1.17 ± 0.09 nW/unit (nearly three orders of magnitude of amplification compared to other NREDs) were achieved in our prototype cell, which was prepared within 30 min. The current NFC-based prototype cell can be parallelized and cascaded to achieve the desired output power and open circuit voltage. This NFC-based scaling-up scheme for energy harvesting based on NRED is promising for the building of self-powered micro/nano-scale systems.

  15. Facile Synthesis of DendriMac Polymers via the Combination of Living Anionic Polymerization and Highly Efficient Coupling Reactions.

    PubMed

    Ma, Hongwei; Wang, Qiuyun; Sang, Wei; Han, Li; Liu, Pibo; Sheng, Heyu; Wang, Yurong; Li, Yang

    2016-01-01

    Two DendriMac polymers (Dendri-hydr and Dendri-click) are efficiently and conveniently synthesized via the combination of living anionic polymerization (LAP) and hydrosilylation/click chemistry. Based on the end-capping of DPE derivatives (DPE-SiH and DPE-DA) toward polymeric anions, the polymeric core and arms are effectively synthesized, and the base polymers can be regarded as polymeric bricks. Hydrosilylation and click chemistry are used as coupling reactions to construct the DendriMac polymers with high efficiency and convenience. The numbers of branched arms are calculated by SEC as 5.84 and 6.08 for Dendri-hydr and Dendri-click, respectively, which indicate that the DendriMac architectures exhibit high structural integrity. Because of its independence, high efficiency, and convenience, the whole construction can be regarded as the "building of polymeric bricks."

  16. Facile synthesis of biocompatible cysteine-coated CuS nanoparticles with high photothermal conversion efficiency for cancer therapy.

    PubMed

    Liu, Xijian; Li, Bo; Fu, Fanfan; Xu, Kaibing; Zou, Rujia; Wang, Qian; Zhang, Bingjie; Chen, Zhigang; Hu, Junqing

    2014-08-14

    The semiconductor compounds have been proven to be promising candidates as a new type of photothermal therapy agent, but unsatisfactory photothermal conversion efficiencies limit their widespread application in photothermal therapy (PTT). Herein, we synthesized cysteine-coated CuS nanoparticles (Cys-CuS NPs) as highly efficient PTT agents by a simple aqueous solution method. The Cys-CuS NPs have a good biocompatibility owing to their biocompatible cysteine coating and exhibit a strong absorption in the near-infrared region due to the localized surface plasma resonances of valence-band free carriers. The photothermal conversion efficiency of Cys-CuS NPs reaches 38.0%, which is much higher than that of the recently reported Cu9S5 and Cu(2-x)Se nanocrystals. More importantly, tumor growth can be efficiently inhibited in vivo by the fatal heat arising from the excellent photothermal effect of Cys-CuS NPs at a low concentration under the irradiation of a 980 nm laser with a safe power density of 0.72 W cm(-2). Therefore, the Cys-CuS NPs have great potential as ideal photothermal agents for cancer therapy. PMID:24950757

  17. Reliable, efficient systems for biomedical research facility

    SciTech Connect

    Basso, P.

    1997-05-01

    Medical Sciences Research Building III (MSRB III) is a 10-story, 207,000 ft{sup 2} (19,230 m{sup 2}) biomedical research facility on the campus of the University of Michigan. The design of MSRB III required a variety of technological solutions to complex design issues. The systems also had to accommodate future modifications. Closely integrated, modular systems with a high degree of flexibility were designed to respond to this requirement. Additionally, designs were kept as simple as possible for operation and maintenance personnel. Integrated electronic controls were used to provide vital data during troubleshooting and maintenance procedures. Equipment was also specified that provides reliability and minimizes maintenance. Other features include 100% redundancy of all central equipment servicing the animal housing area; redundant temperature controls for each individual animal housing room for fail-safe operation to protect the animals against overheating; and accessibility to all items requiring maintenance through an above-ceiling coordination process. It is critical that the engineering systems for MSRB III provide a safe, comfortable, energy efficient environment. The achievement of this design intent was noted by the University`s Commissioning Review Committee which stated: The Commissioning Process performed during both the design phase and construction phase of MSRB III was a significant success, providing an efficiently functioning facility that has been built in accordance with its design intent.

  18. One-pot facile synthesis of branched Ag-ZnO heterojunction nanostructure as highly efficient photocatalytic catalyst

    NASA Astrophysics Data System (ADS)

    Huang, Qingli; Zhang, Qitao; Yuan, Saisai; Zhang, Yongcai; Zhang, Ming

    2015-10-01

    In this paper, the branched Ag-ZnO heterojunction nanostructure and the branched ZnO were synthesized successfully by a facile, green and one-pot hydrothermal method. Such branched heterojunction and the comparing branched pure ZnO were characterized by X-ray diffraction, field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL) and UV-vis diffuse reflectance spectra (DRS). The photocatalytic degradation of RhB aqueous solution and acetaldehyde (CH3CHO) gas results both showed that the branched Ag-ZnO heterojunction possessed the enhanced photocatalytic properties in comparison to the branched ZnO and Ag-ZnO counterparts due to its special interface structures and fast separation of its photogenerated charge carriers. This method is simple, feasible and can provide an important clue for synthesis and application of other branched metal/semiconductor heterojunction nanostructures.

  19. Energy efficiency in California laboratory-type facilities

    SciTech Connect

    Mills, E.; Bell, G.; Sartor, D.

    1996-07-31

    The central aim of this project is to provide knowledge and tools for increasing the energy efficiency and performance of new and existing laboratory-type facilities in California. We approach the task along three avenues: (1) identification of current energy use and savings potential, (2) development of a {ital Design guide for energy- Efficient Research Laboratories}, and (3) development of a research agenda for focused technology development and improving out understanding of the market. Laboratory-type facilities use a considerable amount of energy resources. They are also important to the local and state economy, and energy costs are a factor in the overall competitiveness of industries utilizing laboratory-type facilities. Although the potential for energy savings is considerable, improving energy efficiency in laboratory-type facilities is no easy task, and there are many formidable barriers to improving energy efficiency in these specialized facilities. Insufficient motivation for individual stake holders to invest in improving energy efficiency using existing technologies as well as conducting related R&D is indicative of the ``public goods`` nature of the opportunity to achieve energy savings in this sector. Due to demanding environmental control requirements and specialized processes, laboratory-type facilities epitomize the important intersection between energy demands in the buildings sector and the industrial sector. Moreover, given the high importance and value of the activities conducted in laboratory-type facilities, they represent one of the most powerful contexts in which energy efficiency improvements stand to yield abundant non-energy benefits if properly applied.

  20. Assessment of Efficiency of Regenerative Heating System of Feed Water for High Temperature Turbine Plant on Decentralized Power Engineering Facilities

    NASA Astrophysics Data System (ADS)

    Larionov, Kirill; Gvozdjakov, Dmitrij; Zenkov, Andrej; Zaytsev, Vladimir

    2016-02-01

    The results of theoretical researches on efficiency of air heater use have been presented. The results of the research show the possibility of increase of energy efficiency of electrical power unit on electrical energy consumption by 2% at the initial temperature of steam 1073 K. The possibility of decrease of unit consumption of reference fuel by 4% has been stated.

  1. High power, high frequency component test facility

    NASA Technical Reports Server (NTRS)

    Roth, Mary Ellen; Krawczonek, Walter

    1990-01-01

    The NASA Lewis Research Center has available a high frequency, high power laboratory facility for testing various components of aerospace and/or terrestrial power systems. This facility is described here. All of its capabilities and potential applications are detailed.

  2. Facile and Scalable Fabrication of Highly Efficient Lead Iodide Perovskite Thin-Film Solar Cells in Air Using Gas Pump Method.

    PubMed

    Ding, Bin; Gao, Lili; Liang, Lusheng; Chu, Qianqian; Song, Xiaoxuan; Li, Yan; Yang, Guanjun; Fan, Bin; Wang, Mingkui; Li, Chengxin; Li, Changjiu

    2016-08-10

    Control of the perovskite film formation process to produce high-quality organic-inorganic metal halide perovskite thin films with uniform morphology, high surface coverage, and minimum pinholes is of great importance to highly efficient solar cells. Herein, we report on large-area light-absorbing perovskite films fabrication with a new facile and scalable gas pump method. By decreasing the total pressure in the evaporation environment, the gas pump method can significantly enhance the solvent evaporation rate by 8 times faster and thereby produce an extremely dense, uniform, and full-coverage perovskite thin film. The resulting planar perovskite solar cells can achieve an impressive power conversion efficiency up to 19.00% with an average efficiency of 17.38 ± 0.70% for 32 devices with an area of 5 × 2 mm, 13.91% for devices with a large area up to 1.13 cm(2). The perovskite films can be easily fabricated in air conditions with a relative humidity of 45-55%, which definitely has a promising prospect in industrial application of large-area perovskite solar panels.

  3. Facile and Scalable Fabrication of Highly Efficient Lead Iodide Perovskite Thin-Film Solar Cells in Air Using Gas Pump Method.

    PubMed

    Ding, Bin; Gao, Lili; Liang, Lusheng; Chu, Qianqian; Song, Xiaoxuan; Li, Yan; Yang, Guanjun; Fan, Bin; Wang, Mingkui; Li, Chengxin; Li, Changjiu

    2016-08-10

    Control of the perovskite film formation process to produce high-quality organic-inorganic metal halide perovskite thin films with uniform morphology, high surface coverage, and minimum pinholes is of great importance to highly efficient solar cells. Herein, we report on large-area light-absorbing perovskite films fabrication with a new facile and scalable gas pump method. By decreasing the total pressure in the evaporation environment, the gas pump method can significantly enhance the solvent evaporation rate by 8 times faster and thereby produce an extremely dense, uniform, and full-coverage perovskite thin film. The resulting planar perovskite solar cells can achieve an impressive power conversion efficiency up to 19.00% with an average efficiency of 17.38 ± 0.70% for 32 devices with an area of 5 × 2 mm, 13.91% for devices with a large area up to 1.13 cm(2). The perovskite films can be easily fabricated in air conditions with a relative humidity of 45-55%, which definitely has a promising prospect in industrial application of large-area perovskite solar panels. PMID:27428311

  4. Facile fabrication of highly efficient carbon nanotube thin film replacing CuS counter electrode with enhanced photovoltaic performance in quantum dot-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Gopi, Chandu V. V. M.; Venkata-Haritha, Mallineni; Kim, Soo-Kyoung; Kim, Hee-Je

    2016-04-01

    An ideal counter electrode (CE), with high electrocatalytic activity, high performance stability, cost-efficient and applicable fabrication simplicity, is necessary to give full play to the advantages of quantum dot-sensitized solar cells (QDSSCs). Herein, we report a facile one-step preparation for carbon nanotubes (CNTs) have been explored as an electrocatalyst and low-cost alternative to platinum (Pt) and cuprous sulfide (CuS) CEs for polysulfide reduction in QDSSCs. QDSSC using this newly prepared CNT as a CE achieves a higher power conversion efficiency of 4.67% than those with a CuS (3.67%) or Pt CE (1.56%). Besides, a preliminary stability test reveals that the new CNT CE exhibits good stability. The results of Tafel polarization and electrochemical impedance spectroscopy measurements revealed that the CNTs had higher electrocatalytic activity for the polysulfide redox reaction and a smaller charge transfer resistance (8.61 Ω) at the CE/electrolyte interface than the CuS (21.87 Ω) and Pt (54.99 Ω) CEs. These results indicate that the CNT CE has superior electrocatalytic activity and can potentially replace CuS and Pt as CEs in QDSSCs. The preparation method of the CNT CE is simple and shows much promise as an efficient, stable, cost-effective and environmentally friendly CE for QDSSCs.

  5. Trypsin immobilization on hairy polymer chains hybrid magnetic nanoparticles for ultra fast, highly efficient proteome digestion, facile 18O labeling and absolute protein quantification.

    PubMed

    Qin, Weijie; Song, Zifeng; Fan, Chao; Zhang, Wanjun; Cai, Yun; Zhang, Yangjun; Qian, Xiaohong

    2012-04-01

    In recent years, quantitative proteomic research attracts great attention because of the urgent needs in biological and clinical research, such as biomarker discovery and verification. Currently, mass spectrometry (MS) based bottom up strategy has become the method of choice for proteomic quantification. In this strategy, the amount of proteins is determined by quantifying the corresponding proteolytic peptides of the proteins, therefore highly efficient and complete protein digestion is crucial for achieving accurate quantification results. However, the digestion efficiency and completeness obtained using conventional free protease digestion is not satisfactory for highly complex proteomic samples. In this work, we developed a new type of immobilized trypsin using hairy noncross-linked polymer chains hybrid magnetic nanoparticle as the matrix aiming at ultra fast, highly efficient proteomic digestion and facile (18)O labeling for absolution protein quantification. The hybrid nanoparticle is synthesized by in situ growth of hairy polymer chains from the magnetic nanoparticle surface using surface initiated atom transfer radical polymerization technique. The flexible noncross-linked polymer chains not only provide large amount of binding sites but also work as scaffolds to support three-dimensional trypsin immobilization which leads to increased loading amount and improved accessibility of the immobilized trypsin. For complex proteomic samples, obviously increased digestion efficiency and completeness was demonstrated by 27.2% and 40.8% increase in the number of identified proteins and peptides as well as remarkably reduced undigested proteins residues compared with that obtained using conventional free trypsin digestion. The successful application in absolute protein quantification of enolase from Thermoanaerobacter tengcongensis protein extracts using (18)O labeling and MRM strategy further demonstrated the potential of this hybrid nanoparticle immobilized trypsin

  6. Facile and green reduction of covalently PEGylated nanographene oxide via a `water-only' route for high-efficiency photothermal therapy

    NASA Astrophysics Data System (ADS)

    Chen, Jingqin; Wang, Xiaoping; Chen, Tongsheng

    2014-02-01

    A facile and green strategy is reported for the fabrication of nanosized and reduced covalently PEGylated graphene oxide (nrGO-PEG) with great biocompatibility and high near-infrared (NIR) absorbance. Covalently PEGylated nGO (nGO-PEG) was synthesized by the reaction of nGO-COOH and methoxypolyethylene glycol amine (mPEG-NH2). The neutral and purified nGO-PEG solution was then directly bathed in water at 90°C for 24 h without any additive to obtain nrGO-PEG. Covalent PEGylation not only prevented the aggregation of nGO but also dramatically promoted the reduction extent of nGO during this reduction process. The resulting single-layered nrGO-PEG sheets were approximately 50 nm in average lateral dimension and exhibited great biocompatibility and approximately 7.6-fold increment in NIR absorption. Moreover, this facile reduction process repaired the aromatic structure of GO. CCK-8 and flow cytometry (FCM) assays showed that exposure of A549 cells to 100 μg/mL of nrGO-PEG for 2 h, exhibiting 71.5% of uptake ratio, did not induce significant cytotoxicity. However, after irradiation with 808 nm laser (0.6 W/cm2) for 5 min, the cells incubated with 6 μg/mL of nrGO-PEG solution showed approximately 90% decrease of cell viability, demonstrating the high-efficiency photothermal therapy of nrGO-PEG to tumor cells in vitro. This work established nrGO-PEG as a promising photothermal agent due to its small size, great biocompatibility, high photothermal efficiency, and low cost.

  7. Facile and green reduction of covalently PEGylated nanographene oxide via a ‘water-only’ route for high-efficiency photothermal therapy

    PubMed Central

    2014-01-01

    A facile and green strategy is reported for the fabrication of nanosized and reduced covalently PEGylated graphene oxide (nrGO-PEG) with great biocompatibility and high near-infrared (NIR) absorbance. Covalently PEGylated nGO (nGO-PEG) was synthesized by the reaction of nGO-COOH and methoxypolyethylene glycol amine (mPEG-NH2). The neutral and purified nGO-PEG solution was then directly bathed in water at 90°C for 24 h without any additive to obtain nrGO-PEG. Covalent PEGylation not only prevented the aggregation of nGO but also dramatically promoted the reduction extent of nGO during this reduction process. The resulting single-layered nrGO-PEG sheets were approximately 50 nm in average lateral dimension and exhibited great biocompatibility and approximately 7.6-fold increment in NIR absorption. Moreover, this facile reduction process repaired the aromatic structure of GO. CCK-8 and flow cytometry (FCM) assays showed that exposure of A549 cells to 100 μg/mL of nrGO-PEG for 2 h, exhibiting 71.5% of uptake ratio, did not induce significant cytotoxicity. However, after irradiation with 808 nm laser (0.6 W/cm2) for 5 min, the cells incubated with 6 μg/mL of nrGO-PEG solution showed approximately 90% decrease of cell viability, demonstrating the high-efficiency photothermal therapy of nrGO-PEG to tumor cells in vitro. This work established nrGO-PEG as a promising photothermal agent due to its small size, great biocompatibility, high photothermal efficiency, and low cost. PMID:24548613

  8. Facile fabrication of high-efficiency near-infrared absorption film with tungsten bronze nanoparticle dense layer

    PubMed Central

    2014-01-01

    An excellent transparent film with effective absorption property in near-infrared (NIR) region based on cesium-doped tungsten oxide nanoparticles was fabricated using a facile double layer coating method via the theoretical considerations. The optical performance was evaluated; the double layer-coated film exhibited 10% transmittance at 1,000 nm in the NIR region and over 80% transmittance at 550 nm in the visible region. To optimize the selectivity, the optical spectrum of this film was correlated with a theoretical model by combining the contributions of the Mie-Gans absorption-based localized surface plasmon resonance and reflections by the interfaces of the heterogeneous layers and the nanoparticles in the film. Through comparison of the composite and double layer coating method, the difference of the nanoscale distances between nanoparticles in each layer was significantly revealed. It is worth noting that the nanodistance between the nanoparticles decreased in the double layer film, which enhanced the optical properties of the film, yielding a haze value of 1% or less without any additional process. These results are very attractive for the nanocomposite coating process, which would lead to industrial fields of NIR shielding and thermo-medical applications. PACS 78.67.Sc; 78.67.Bf; 81.15.-z PMID:24982605

  9. Facile fabrication of high-efficiency near-infrared absorption film with tungsten bronze nanoparticle dense layer

    NASA Astrophysics Data System (ADS)

    Lee, Seong Yun; Kim, Jae Young; Lee, Jun Young; Song, Ho Jun; Lee, Sangkug; Choi, Kyung Ho; Shin, Gyojic

    2014-06-01

    An excellent transparent film with effective absorption property in near-infrared (NIR) region based on cesium-doped tungsten oxide nanoparticles was fabricated using a facile double layer coating method via the theoretical considerations. The optical performance was evaluated; the double layer-coated film exhibited 10% transmittance at 1,000 nm in the NIR region and over 80% transmittance at 550 nm in the visible region. To optimize the selectivity, the optical spectrum of this film was correlated with a theoretical model by combining the contributions of the Mie-Gans absorption-based localized surface plasmon resonance and reflections by the interfaces of the heterogeneous layers and the nanoparticles in the film. Through comparison of the composite and double layer coating method, the difference of the nanoscale distances between nanoparticles in each layer was significantly revealed. It is worth noting that the nanodistance between the nanoparticles decreased in the double layer film, which enhanced the optical properties of the film, yielding a haze value of 1% or less without any additional process. These results are very attractive for the nanocomposite coating process, which would lead to industrial fields of NIR shielding and thermo-medical applications.

  10. NETL- High-Pressure Combustion Research Facility

    ScienceCinema

    None

    2016-07-12

    NETL's High-Pressure Combustion Facility is a unique resource within the National Laboratories system. It provides the test capabilities needed to evaluate new combustion concepts for high-pressure, high-temperature hydrogen and natural gas turbines. These concepts will be critical for the next generation of ultra clean, ultra efficient power systems.

  11. NETL- High-Pressure Combustion Research Facility

    SciTech Connect

    2013-07-08

    NETL's High-Pressure Combustion Facility is a unique resource within the National Laboratories system. It provides the test capabilities needed to evaluate new combustion concepts for high-pressure, high-temperature hydrogen and natural gas turbines. These concepts will be critical for the next generation of ultra clean, ultra efficient power systems.

  12. Facile and highly efficient removal of trace Gd(III) by adsorption of colloidal graphene oxide suspensions sealed in dialysis bag.

    PubMed

    Chen, Weifan; Wang, Linlin; Zhuo, Mingpeng; Liu, Yue; Wang, Yiping; Li, Yongxiu

    2014-08-30

    A facile, highly efficient and second-pollution-free strategy to remove trace Gd(III) from aqueous solutions by adsorption of colloidal graphene oxide (GO) suspensions in dialysis bag has been developed. The effects of pH, ionic strength and temperature on Gd(III) adsorption, and the pH-dependent desorption were investigated. The maximum adsorption capacity of Gd(III)on GO at pH=5.9±0.1 and T=303K was 286.86mgg(-1), higher than any other currently reported. The Gd(III)-saturated GO suspension could resume colloidal state in 0.1M HNO3 with desorption rate of 85.00% in the fifth adsorption-desorption cycle. Gd(III) adsorption rate on GO was dependent more on pH and ionic strength than on temperature. The abundant oxygen-containing functional groups such as carboxyl and hydroxyl played a vital role on adsorption. The thermodynamics and kinetics investigations revealed that the adsorption of Gd(III) on GO was an endothermic, spontaneous and monolayer absorption process, which well fitted the pseudo-second-order model. GO could be a promising adsorbent applied in the enrichment and removal of lanthanides from aqueous solutions. More significantly, the combination of colloidal GO suspension with dialysis membrane facilely solves the re-pollution of the treated solutions due to the great difficulties in separation and recovery of GO.

  13. Facile and highly efficient removal of trace Gd(III) by adsorption of colloidal graphene oxide suspensions sealed in dialysis bag.

    PubMed

    Chen, Weifan; Wang, Linlin; Zhuo, Mingpeng; Liu, Yue; Wang, Yiping; Li, Yongxiu

    2014-08-30

    A facile, highly efficient and second-pollution-free strategy to remove trace Gd(III) from aqueous solutions by adsorption of colloidal graphene oxide (GO) suspensions in dialysis bag has been developed. The effects of pH, ionic strength and temperature on Gd(III) adsorption, and the pH-dependent desorption were investigated. The maximum adsorption capacity of Gd(III)on GO at pH=5.9±0.1 and T=303K was 286.86mgg(-1), higher than any other currently reported. The Gd(III)-saturated GO suspension could resume colloidal state in 0.1M HNO3 with desorption rate of 85.00% in the fifth adsorption-desorption cycle. Gd(III) adsorption rate on GO was dependent more on pH and ionic strength than on temperature. The abundant oxygen-containing functional groups such as carboxyl and hydroxyl played a vital role on adsorption. The thermodynamics and kinetics investigations revealed that the adsorption of Gd(III) on GO was an endothermic, spontaneous and monolayer absorption process, which well fitted the pseudo-second-order model. GO could be a promising adsorbent applied in the enrichment and removal of lanthanides from aqueous solutions. More significantly, the combination of colloidal GO suspension with dialysis membrane facilely solves the re-pollution of the treated solutions due to the great difficulties in separation and recovery of GO. PMID:25108829

  14. High-pressure water facility

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA Test Operations Group employees, from left, Todd Pearson, Tim Delcuze and Rodney Wilkinson maintain a water pump in Stennis Space Center's high-pressure water facility. The three were part of a group of employees who rode out Hurricane Katrina at the facility and helped protect NASA's rocket engine test complex.

  15. High-Average Power Facilities

    SciTech Connect

    Dowell, David H.; Power, John G.; /Argonne

    2012-09-05

    There has been significant progress in the development of high-power facilities in recent years yet major challenges remain. The task of WG4 was to identify which facilities were capable of addressing the outstanding R&D issues presently preventing high-power operation. To this end, information from each of the facilities represented at the workshop was tabulated and the results are presented herein. A brief description of the major challenges is given, but the detailed elaboration can be found in the other three working group summaries.

  16. Facile synthesis of porous CuS film as a high efficient counter electrode for quantum-dot-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Lin, Yibing; Lin, Yu; Wu, Jihuai; Zhang, Xiaolong; Fang, Biaopeng

    2016-06-01

    In this paper, porous CuS film has been successfully prepared by a facile method and employed as a counter electrode (CE) in quantum-dot-sensitized solar cells (QDSSCs) for its highest catalytic activity. This CuS thin film was deposited on FTO substrate via spin coating process which is simple to operate, and its electrochemical properties were further studied by EIS and Tafel measurement. With the cycling time of depositing CuS up to 8, it displays high electrocatalytic activity toward polysulfide reduction, rationalizing the improved QDSSCs performance. Using the CdS/CdSe-sensitized QDSSCs, the cells exhibit improved short-circuit photocurrent density ( J sc) and fill factor (FF), achieving solar cell conversion efficiency ( η) as high as 5.60 % under AM 1.5 illumination of 100 mW cm-2. This work provides a novel and simple method for the preparation of CEs, which could be utilized in other metal sulfides CEs for QDSSCs.

  17. Facile in situ growth of highly monodispersed Ag nanoparticles on electrospun PU nanofiber membranes: Flexible and high efficiency substrates for surface enhanced Raman scattering

    NASA Astrophysics Data System (ADS)

    Amarjargal, Altangerel; Tijing, Leonard D.; Shon, Ho Kyong; Park, Chan-Hee; Kim, Cheol Sang

    2014-07-01

    In this study, by utilizing a two-step route of electrospinning and polyol immersion, in the absence of any surfactant or sensitizing and stabilizing reagent, a well-distributed assembly of Ag NPs on the electrospun polyurethane (PU) nanofibers was successfully fabricated through a simple and controllable manner. Based on the FE-SEM, XRD and FT-IR analyses, the polyol medium plays an important role in the growth of highly monodispersed Ag NPs, wherein the hydroxyl group of ethylene glycol (EG) can be bridged to the amide group on the surface of the PU nanofibers through intermolecular hydrogen bonds. Fabrication of a polymer fibrous membrane effectively attached/decorated with noble metal NPs, which is essential as flexible and high efficiency substrates for SERS application where the molecule analytes are directly adsorbed on their surfaces is important, could be realized by the present electrospun PU-Ag(EG) nanofibers, employing 4-mercaptobenzoic acid (4-MBA) as probe molecules.

  18. High Power Proton Facilities

    NASA Astrophysics Data System (ADS)

    Nagaitsev, Sergei

    2015-04-01

    This presentation will provide an overview of the capabilities and challenges of high intensity proton accelerators, such as J-PARC, Fermilab MI, SNS, ISIS, PSI, ESS (in the future) and others. The presentation will focus on lessons learned, new concepts, beam loss mechanisms and methods to mitigate them.

  19. Status of the ELSA facility. Last results at high efficiency and first test of a 60 parameters, on line tunable wiggler

    NASA Astrophysics Data System (ADS)

    Guimbal, Ph.; Binet, A.; Blésès, J. P.; Fontenay, V.; Joly, S.; Loulergue, A.; Marmouget, J. G.; Pranal, Y.; Rodolfo, J.; Sabary, F.; Striby, S.; Touati, D.

    1996-02-01

    Prior to the 1995 shutdown of the ELSA facility, we recorded our first time-resolved photon spectra. They clearly showed the chaotic behaviour predicted at high coupling but their low signal-to-noise and time resolution precluded a fine analysis. A new high-sensitivity, high-speed spectrometer should overcome these limits. We also successfully tested a new device based on secondary emission to acquire time-resolved electron spectra and we made preliminary tests of the 60-parameters-on-line tapering of the TRIA wiggler. The facility is to be run again at the end of the year with an improved level of performance and reliability.

  20. Facile deposition of Ag{sub 3}PO{sub 4} on graphene-like MoS{sub 2} nanosheets for highly efficient photocatalysis

    SciTech Connect

    Wang, Peifu; Shi, Penghui; Hong, Yuanchen; Zhou, Xuejun; Yao, Weifeng

    2015-02-15

    Graphical abstract: The photocatalytic performance of Ag{sub 3}PO{sub 4} was highly improved by the in situ deposition of Ag{sub 3}PO{sub 4} particles on graphene-like MoS{sub 2} nanosheets. - Highlights: • A novel composite photocatalyst was synthesized by depositing Ag{sub 3}PO{sub 4} on the graphene-like MoS{sub 2} nanosheets. • Ag{sub 3}PO{sub 4}/MoS{sub 2} photocatalyst exhibited a high photocatalytic activity for RhB degradation. • Graphene-like MoS{sub 2} nanosheets. • MoS{sub 2} nanosheets play an important role in photocatalytic activity by serving as an effective acceptor of the photogenerated carriers. - Abstract: A facile method for the in situ deposition of Ag{sub 3}PO{sub 4} on graphene-like MoS{sub 2} nanosheets was developed to improve the photocatalytic performance of Ag{sub 3}PO{sub 4} catalysts. The heterostructure of Ag{sub 3}PO{sub 4}/MoS{sub 2} composites was characterized by using X-ray diffraction spectra (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The prepared Ag{sub 3}PO{sub 4}/MoS{sub 2} photocatalyst exhibited a much higher photocatalytic activity than that of Ag{sub 3}PO{sub 4} for the degradation of Rhodamine B (RhB) under visible light irradiation (>400 nm). The improved photocatalytic activity of Ag{sub 3}PO{sub 4}/MoS{sub 2} is attributed to the efficient separation of photogenerated electron–hole pairs in the composite. This result provides a new perspective on the design of high-performance photocatalysts which is promising for energy applications.

  1. High efficiency incandescent lighting

    SciTech Connect

    Bermel, Peter; Ilic, Ognjen; Chan, Walker R.; Musabeyoglu, Ahmet; Cukierman, Aviv Ruben; Harradon, Michael Robert; Celanovic, Ivan; Soljacic, Marin

    2014-09-02

    Incandescent lighting structure. The structure includes a thermal emitter that can, but does not have to, include a first photonic crystal on its surface to tailor thermal emission coupled to, in a high-view-factor geometry, a second photonic filter selected to reflect infrared radiation back to the emitter while passing visible light. This structure is highly efficient as compared to standard incandescent light bulbs.

  2. High Exposure Facility Technical Description

    SciTech Connect

    Carter, Gregory L.; Stithem, Arthur R.; Murphy, Mark K.; Smith, Alex K.

    2008-02-12

    The High Exposure Facility is a collimated high-level gamma irradiator that is located in the basement of the 318 building. It was custom developed by PNNL back in 1982 to meet the needs for high range radiological instrument calibrations and dosimeter irradiations. At the time no commercially available product existed that could create exposure rates up to 20,000 R/h. This document is intended to pass on the design criteria that was employed to create this unique facility, while maintaining compliance with ANSI N543-1974, "General Safety Standard for Installations Using Non-Medical X-Ray and Sealed Gamma-Ray Sources, Energies up to 10 MeV."

  3. High efficiency magnetic bearings

    NASA Technical Reports Server (NTRS)

    Studer, Philip A.; Jayaraman, Chaitanya P.; Anand, Davinder K.; Kirk, James A.

    1993-01-01

    Research activities concerning high efficiency permanent magnet plus electromagnet (PM/EM) pancake magnetic bearings at the University of Maryland are reported. A description of the construction and working of the magnetic bearing is provided. Next, parameters needed to describe the bearing are explained. Then, methods developed for the design and testing of magnetic bearings are summarized. Finally, a new magnetic bearing which allows active torque control in the off axes directions is discussed.

  4. High Efficiency, Clean Combustion

    SciTech Connect

    Donald Stanton

    2010-03-31

    Energy use in trucks has been increasing at a faster rate than that of automobiles within the U.S. transportation sector. According to the Energy Information Administration (EIA) Annual Energy Outlook (AEO), a 23% increase in fuel consumption for the U.S. heavy duty truck segment is expected between 2009 to 2020. The heavy duty vehicle oil consumption is projected to grow between 2009 and 2050 while light duty vehicle (LDV) fuel consumption will eventually experience a decrease. By 2050, the oil consumption rate by LDVs is anticipated to decrease below 2009 levels due to CAFE standards and biofuel use. In contrast, the heavy duty oil consumption rate is anticipated to double. The increasing trend in oil consumption for heavy trucks is linked to the vitality, security, and growth of the U.S. economy. An essential part of a stable and vibrant U.S. economy is a productive U.S. trucking industry. Studies have shown that the U.S. gross domestic product (GDP) is strongly correlated to freight transport. Over 90% of all U.S. freight tonnage is transported by diesel power and over 75% is transported by trucks. Given the vital role that the trucking industry plays in the economy, improving the efficiency of the transportation of goods was a central focus of the Cummins High Efficient Clean Combustion (HECC) program. In a commercial vehicle, the diesel engine remains the largest source of fuel efficiency loss, but remains the greatest opportunity for fuel efficiency improvements. In addition to reducing oil consumption and the dependency on foreign oil, this project will mitigate the impact on the environment by meeting US EPA 2010 emissions regulations. Innovation is a key element in sustaining a U.S. trucking industry that is competitive in global markets. Unlike passenger vehicles, the trucking industry cannot simply downsize the vehicle and still transport the freight with improved efficiency. The truck manufacturing and supporting industries are faced with numerous

  5. Superstructure high efficiency photovoltaics

    NASA Technical Reports Server (NTRS)

    Wagner, M.; So, L. C.; Leburton, J. P.

    1987-01-01

    A novel class of photovoltaic cascade structures is introduced which features multijunction upper subcells. These superstructure high efficiency photovoltaics (SHEP's) exhibit enhanced upper subcell spectral response because of the additional junctions which serve to reduce bulk recombination losses by decreasing the mean collection distance for photogenerated minority carriers. Two possible electrical configurations were studied and compared: a three-terminal scheme that allows both subcells to be operated at their individual maximum power points and a two-terminal configuration with an intercell ohmic contact for series interconnection. The three-terminal devices were found to be superior both in terms of beginning-of-life expectancy and radiation tolerance. Realistic simulations of three-terminal AlGaAs/GaAs SHEP's show that one sun AMO efficiencies in excess of 26 percent are possible.

  6. High efficiency photoionization detector

    DOEpatents

    Anderson, D.F.

    1984-01-31

    A high efficiency photoionization detector is described using tetraaminoethylenes in a gaseous state having a low ionization potential and a relative photoionization cross section which closely matches the emission spectrum of xenon gas. Imaging proportional counters are also disclosed using the novel photoionization detector of the invention. The compound of greatest interest is TMAE which comprises tetrakis(dimethylamino)ethylene which has a measured ionization potential of 5.36 [+-] 0.02 eV, and a vapor pressure of 0.35 torr at 20 C. 6 figs.

  7. High efficiency multifrequency feed

    NASA Technical Reports Server (NTRS)

    Ajioka, J. S.; Tsuda, G. I.; Leeper, W. A. (Inventor)

    1974-01-01

    Antenna systems and particularly compact and simple antenna feeds which can transmit and receive simultaneously in at least three frequency bands, each with high efficiency and polarization diversity are described. The feed system is applicable for frequency bands having nominal frequency bands with the ratio 1:4:6. By way of example, satellite communications telemetry bands operate in frequency bands 0.8 - 1.0 GHz, 3.7 - 4.2 GHz and 5.9 - 6.4 GHz. In addition, the antenna system of the invention has monopulse capability for reception with circular or diverse polarization at frequency band 1.

  8. High efficiency photoionization detector

    DOEpatents

    Anderson, David F.

    1984-01-01

    A high efficiency photoionization detector using tetraaminoethylenes in a gaseous state having a low ionization potential and a relative photoionization cross section which closely matches the emission spectrum of xenon gas. Imaging proportional counters are also disclosed using the novel photoionization detector of the invention. The compound of greatest interest is TMAE which comprises tetrakis(dimethylamino)ethylene which has a measured ionization potential of 5.36.+-.0.02 eV, and a vapor pressure of 0.35 torr at 20.degree. C.

  9. HIGH EFFICIENCY SYNGAS GENERATION

    SciTech Connect

    Robert J. Copeland; Yevgenia Gershanovich; Brian Windecker

    2005-02-01

    This project investigated an efficient and low cost method of auto-thermally reforming natural gas to hydrogen and carbon monoxide. Reforming is the highest cost step in producing products such as methanol and Fisher Tropsch liquids (i.e., gas to liquids); and reducing the cost of reforming is the key to reducing the cost of these products. Steam reforming is expensive because of the high cost of the high nickel alloy reforming tubes (i.e., indirectly fired reforming tubes). Conventional auto-thermal or Partial Oxidation (POX) reforming minimizes the size and cost of the reformers and provides a near optimum mixture of CO and hydrogen. However POX requires pure oxygen, which consumes power and significantly increases the cost to reforming. Our high efficiency process extracts oxygen from low-pressure air with novel oxygen sorbent and transfers the oxygen to a nickel-catalyzed reformer. The syngas is generated at process pressure (typically 20 to 40 bar) without nitrogen dilution and has a 1CO to 2H{sub 2} ratio that is near optimum for the subsequent production of Fisher-Tropsch liquid to liquids and other chemicals (i.e., Gas to Liquids, GTL). Our high process efficiency comes from the way we transfer the oxygen into the reformer. All of the components of the process, except for the oxygen sorbent, are commonly used in commercial practice. A process based on a longlived, regenerable, oxygen transfer sorbent could substantially reduce the cost of natural gas reforming to syngas. Lower cost syngas (CO + 2H{sub 2}) that is the feedstock for GTL would reduce the cost of GTL and for other commercial applications (e.g., methanol, other organic chemicals). The vast gas resources of Alaska's North Slope (ANS) offer more than 22 Tcf of gas and GTL production in this application alone, and could account for as much as 300,000 to 700,000 bpd for 20 to 30+ years. We developed a new sorbent, which is an essential part of the High Efficiency Oxygen Process (HOP). We tested the

  10. High-efficiency CARM

    SciTech Connect

    Bratman, V.L.; Kol`chugin, B.D.; Samsonov, S.V.; Volkov, A.B.

    1995-12-31

    The Cyclotron Autoresonance Maser (CARM) is a well-known variety of FEMs. Unlike the ubitron in which electrons move in a periodical undulator field, in the CARM the particles move along helical trajectories in a uniform magnetic field. Since it is much simpler to generate strong homogeneous magnetic fields than periodical ones for a relatively low electron energy ({Brit_pounds}{le}1-3 MeV) the period of particles` trajectories in the CARM can be sufficiently smaller than in the undulator in which, moreover, the field decreases rapidly in the transverse direction. In spite of this evident advantage, the number of papers on CARM is an order less than on ubitron, which is apparently caused by the low (not more than 10 %) CARM efficiency in experiments. At the same time, ubitrons operating in two rather complicated regimes-trapping and adiabatic deceleration of particles and combined undulator and reversed guiding fields - yielded efficiencies of 34 % and 27 %, respectively. The aim of this work is to demonstrate that high efficiency can be reached even for a simplest version of the CARM. In order to reduce sensitivity to an axial velocity spread of particles, a short interaction length where electrons underwent only 4-5 cyclotron oscillations was used in this work. Like experiments, a narrow anode outlet of a field-emission electron gun cut out the {open_quotes}most rectilinear{close_quotes} near-axis part of the electron beam. Additionally, magnetic field of a small correcting coil compensated spurious electron oscillations pumped by the anode aperture. A kicker in the form of a sloping to the axis frame with current provided a control value of rotary velocity at a small additional velocity spread. A simple cavity consisting of a cylindrical waveguide section restricted by a cut-off waveguide on the cathode side and by a Bragg reflector on the collector side was used as the CARM-oscillator microwave system.

  11. Facile method for synthesis of TiO{sub 2} film and its application in high efficiency dye sensitized-solar cell (DSSC)

    SciTech Connect

    Widiyandari, Hendri Gunawan, S. K.V.; Suseno, Jatmiko Endro; Purwanto, Agus; Diharjo, Kuncoro

    2014-02-24

    Dye-sensitized solar cells (DSSC) is a device which converts a solar energy to electrical energy. Different with semiconductor thin film based solar cell, DSSC utilize the sensitized-dye to absorb the photon and semiconductor such as titanium dioxide (TiO{sub 2}) and zinc oxide (ZnO) as a working electrode photoanode. In this report, the preparation of TiO{sub 2} film using a facile method of spray deposition and its application in DSSC have been presented. TiO{sub 2} photoanode was synthesized by growing the droplet of titanium tetraisopropoxide diluted in acid solution on the substrate of conductive glass flourine-doped tin oxide (FTO) with variation of precursor volume. DSSC was assemblied by sandwiching both of photoanode electrode and platinum counter electrode subsequently filling the area between these electrodes with triodine/iodine electrolite solution as redox pairs. The characterization of the as prepared DSSC using solar simulator (AM 1.5G, 100 mW/cm{sup 2}) and I-V source meter Keithley 2400 showed that the performance of DSSC was affected by the precursor volume.. The overall conversion efficiency of DSSC using the optimum TiO{sub 2} film was about 1.97% with the open circuit voltage (V{sub oc}) of 0.73 V, short circuit current density (J{sub sc}) of 4.61 mA and fill factor (FF) of 0.58.

  12. High Efficiency Integrated Package

    SciTech Connect

    Ibbetson, James

    2013-09-15

    Solid-state lighting based on LEDs has emerged as a superior alternative to inefficient conventional lighting, particularly incandescent. LED lighting can lead to 80 percent energy savings; can last 50,000 hours – 2-50 times longer than most bulbs; and contains no toxic lead or mercury. However, to enable mass adoption, particularly at the consumer level, the cost of LED luminaires must be reduced by an order of magnitude while achieving superior efficiency, light quality and lifetime. To become viable, energy-efficient replacement solutions must deliver system efficacies of ≥ 100 lumens per watt (LPW) with excellent color rendering (CRI > 85) at a cost that enables payback cycles of two years or less for commercial applications. This development will enable significant site energy savings as it targets commercial and retail lighting applications that are most sensitive to the lifetime operating costs with their extended operating hours per day. If costs are reduced substantially, dramatic energy savings can be realized by replacing incandescent lighting in the residential market as well. In light of these challenges, Cree proposed to develop a multi-chip integrated LED package with an output of > 1000 lumens of warm white light operating at an efficacy of at least 128 LPW with a CRI > 85. This product will serve as the light engine for replacement lamps and luminaires. At the end of the proposed program, this integrated package was to be used in a proof-of-concept lamp prototype to demonstrate the component’s viability in a common form factor. During this project Cree SBTC developed an efficient, compact warm-white LED package with an integrated remote color down-converter. Via a combination of intensive optical, electrical, and thermal optimization, a package design was obtained that met nearly all project goals. This package emitted 1295 lm under instant-on, room-temperature testing conditions, with an efficacy of 128.4 lm/W at a color temperature of ~2873

  13. Facile method to prepare poly(S-co-HEA)/Ag nanocomposite particles with high efficient catalytic activity and surface enhanced Raman scattering

    NASA Astrophysics Data System (ADS)

    Chao, Zhiyin; Wang, Lan; Song, Linyong; Zhou, Yifeng; Nie, Wangyan; Chen, Pengpeng

    2015-02-01

    Surface hydroxyl-functionalized poly(styrene-co-hydroxyethyl acrylate) [P(S-co-HEA)] microsphere were used to prepare P(S-co-HEA)/silver composite particles. Based on the weak interaction between silver ions and hydroxyl, silver ions were adsorbed onto the polymer surface and reduced by diethanolamine (DEA). The morphology of P(S-co-HEA)/Ag was easily controlled by the molar ratio of DEA/AgNO3. The composite particles were characterized by SEM, XRD, and UV-vis spectroscopy. The obtained P(S-co-HEA)/Ag particles with small and denser silver nanoparticles showed a high efficient activity to catalyze reduction of methylene blue (MB). While the P(S-co-HEA)/Ag particles with big and denser silver nanoparticles showed highly sensitive Raman enhanced performance.

  14. Facile synthesis of mesoporous spinel NiCo2O4 nanostructures as highly efficient electrocatalysts for urea electro-oxidation

    NASA Astrophysics Data System (ADS)

    Ding, Rui; Qi, Li; Jia, Mingjun; Wang, Hongyu

    2014-01-01

    Mesoporous spinel nickel cobaltite (NiCo2O4) nanostructures were synthesized via a facile chemical deposition method coupled with a simple post-annealing process. The physicochemical properties were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS) and nitrogen sorption measurements. The electrocatalytic performances were investigated by cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) tests. The obtained NiCo2O4 materials exhibit typical agglomerate mesoporous nanostructures with a large surface area (190.1 m2 g-1) and high mesopore volume (0.943 cm3 g-1). Remarkably, the NiCo2O4 shows much higher catalytic activity, lower overpotential, better stability and greater tolerance towards urea electro-oxidation compared to those of cobalt oxide (Co3O4) synthesized by the same procedure. The NiCo2O4 electrode delivers a current density of 136 mA cm-2 mg-1 at 0.7 V (vs. Hg/HgO) in 1 M KOH and 0.33 M urea electrolytes accompanied with a desirable stability. The impressive electrocatalytic activity is largely ascribed to the high intrinsic electronic conductivity, superior mesoporous nanostructures and rich surface Ni active species of the NiCo2O4 materials, which can largely boost the interfacial electroactive sites and charge transfer rates for urea electro-oxidation, indicating promising applications in future wastewater remediation, hydrogen production and fuel cells.Mesoporous spinel nickel cobaltite (NiCo2O4) nanostructures were synthesized via a facile chemical deposition method coupled with a simple post-annealing process. The physicochemical properties were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS) and nitrogen sorption measurements. The electrocatalytic performances were investigated by cyclic voltammetry

  15. Wastewater treatment facilities: Energy efficient improvements and cogeneration

    SciTech Connect

    Kunkle, R.; Gray, R.; Delzel, D.

    1992-10-01

    The Washington State Energy Office (WSEO) has worked with both the Bonneville Power Administration (BPA) and the US Department of Energy to provide technical and financial assistance to local governments. Based on a recent study conducted by Ecotope for WSEO, local governments spend an estimated $45 million on utility bills statewide. Water and wastewater facilities account for almost a third of this cost. As a result, WSEO decided to focus its efforts on the energy intensive water and wastewater sector. The ultimate goal of this project was to develop mechanisms to incorporate energy efficiency improvements into wastewater treatment facilities in retrofits and during upgrades, remodels, and new construction. Project activities included the following: The review of the existing regulatory environment for treatment system construction, A summary of financing options for efficiency improvements in treatment facilities, A literature review of energy efficiency opportunities in treatment plants, Survey and site visits to characterize existing facilities in Washington State, Estimates of the energy efficiency and cogeneration potential in the sector, and A case study to illustrate the implementation of an efficiency improvement in a treatment facility.

  16. AET's new energy-efficient facility gears up for production

    SciTech Connect

    Pucci, A.

    1993-01-01

    American Energy Technologies, Inc. (AET), a company based just north of Green Cove Springs, Florida, has become the largest manufacturer of solar thermal products in the U.S. Phase 1 of the construction of AET's new manufacturing facility, which commenced in October 1992, was completed in April 1993. It houses high-output tooling designed by AET to ensure affordable, high-quality solar thermal hardware which is rated among the most efficient in the world today. The AET facility has integrated a number of energy-efficient design considerations and conservation measures. The passive-solar design of the building minimizes direct solar gain in the summer and maximizes tropical winds for passive cooling. Strategically placed native landscaping requires minimal maintenance, thus reducing water consumption, and provides natural shading for the offices. The exterior walls are constructed of Poly Steel hollow-core styrofoam forms filled with pumped concrete. This design provides an insulation rate of R-22, a wind load of 160 mph, and a two-hour fire rating. The light-colored office and the plant's exterior skin assist in reducing the cooling load with the protection of Lomit, a spray-applied radiant barrier manufactured by SOLEC Corporation, which coats the office roof decks. Climate control for the manufacturing area is provided by an AET solar heating system which works in tandem with two LPG Amana Command Aire 80s for back up. Office space heating is supplied by a warm forced-air system by US Solar Corporation which utilizes a 320-square-foot solar array with a 1,000-gallon storage tank. Circulation is powered by a Siemens Solar Pro photovoltaic array and the thermal system also provides solar hot water for the manufacturing process.

  17. Facile fabrication of large-grain CH3NH3PbI3-xBrx films for high-efficiency solar cells via CH3NH3Br-selective Ostwald ripening

    DOE PAGESBeta

    Yang, Mengjin; Zhang, Taiyang; Schulz, Philip; Li, Zhen; Li, Ge; Kim, Dong Hoe; Guo, Nanjie; Berry, Joseph J.; Zhu, Kai; Zhao, Yixin

    2016-08-01

    Organometallic halide perovskite solar cells (PSCs) have shown great promise as a low-cost, high-efficiency photovoltaic technology. Structural and electro-optical properties of the perovskite absorber layer are most critical to device operation characteristics. Here we present a facile fabrication of high-efficiency PSCs based on compact, large-grain, pinhole-free CH3NH3PbI3-xBrx (MAPbI3-xBrx) thin films with high reproducibility. A simple methylammonium bromide (MABr) treatment via spin-coating with a proper MABr concentration converts MAPbI3 thin films with different initial film qualities (for example, grain size and pinholes) to high-quality MAPbI3-xBrx thin films following an Ostwald ripening process, which is strongly affected by MABr concentration and ismore » ineffective when replacing MABr with methylammonium iodide. A higher MABr concentration enhances I-Br anion exchange reaction, yielding poorer device performance. Lastly, this MABr-selective Ostwald ripening process improves cell efficiency but also enhances device stability and thus represents a simple, promising strategy for further improving PSC performance with higher reproducibility and reliability.« less

  18. Facile fabrication of large-grain CH3NH3PbI3−xBrx films for high-efficiency solar cells via CH3NH3Br-selective Ostwald ripening

    PubMed Central

    Yang, Mengjin; Zhang, Taiyang; Schulz, Philip; Li, Zhen; Li, Ge; Kim, Dong Hoe; Guo, Nanjie; Berry, Joseph J.; Zhu, Kai; Zhao, Yixin

    2016-01-01

    Organometallic halide perovskite solar cells (PSCs) have shown great promise as a low-cost, high-efficiency photovoltaic technology. Structural and electro-optical properties of the perovskite absorber layer are most critical to device operation characteristics. Here we present a facile fabrication of high-efficiency PSCs based on compact, large-grain, pinhole-free CH3NH3PbI3−xBrx (MAPbI3−xBrx) thin films with high reproducibility. A simple methylammonium bromide (MABr) treatment via spin-coating with a proper MABr concentration converts MAPbI3 thin films with different initial film qualities (for example, grain size and pinholes) to high-quality MAPbI3−xBrx thin films following an Ostwald ripening process, which is strongly affected by MABr concentration and is ineffective when replacing MABr with methylammonium iodide. A higher MABr concentration enhances I–Br anion exchange reaction, yielding poorer device performance. This MABr-selective Ostwald ripening process improves cell efficiency but also enhances device stability and thus represents a simple, promising strategy for further improving PSC performance with higher reproducibility and reliability. PMID:27477212

  19. Facile fabrication of large-grain CH3NH3PbI3-xBrx films for high-efficiency solar cells via CH3NH3Br-selective Ostwald ripening

    NASA Astrophysics Data System (ADS)

    Yang, Mengjin; Zhang, Taiyang; Schulz, Philip; Li, Zhen; Li, Ge; Kim, Dong Hoe; Guo, Nanjie; Berry, Joseph J.; Zhu, Kai; Zhao, Yixin

    2016-08-01

    Organometallic halide perovskite solar cells (PSCs) have shown great promise as a low-cost, high-efficiency photovoltaic technology. Structural and electro-optical properties of the perovskite absorber layer are most critical to device operation characteristics. Here we present a facile fabrication of high-efficiency PSCs based on compact, large-grain, pinhole-free CH3NH3PbI3-xBrx (MAPbI3-xBrx) thin films with high reproducibility. A simple methylammonium bromide (MABr) treatment via spin-coating with a proper MABr concentration converts MAPbI3 thin films with different initial film qualities (for example, grain size and pinholes) to high-quality MAPbI3-xBrx thin films following an Ostwald ripening process, which is strongly affected by MABr concentration and is ineffective when replacing MABr with methylammonium iodide. A higher MABr concentration enhances I-Br anion exchange reaction, yielding poorer device performance. This MABr-selective Ostwald ripening process improves cell efficiency but also enhances device stability and thus represents a simple, promising strategy for further improving PSC performance with higher reproducibility and reliability.

  20. Facile fabrication of large-grain CH3NH3PbI3-xBrx films for high-efficiency solar cells via CH3NH3Br-selective Ostwald ripening.

    PubMed

    Yang, Mengjin; Zhang, Taiyang; Schulz, Philip; Li, Zhen; Li, Ge; Kim, Dong Hoe; Guo, Nanjie; Berry, Joseph J; Zhu, Kai; Zhao, Yixin

    2016-01-01

    Organometallic halide perovskite solar cells (PSCs) have shown great promise as a low-cost, high-efficiency photovoltaic technology. Structural and electro-optical properties of the perovskite absorber layer are most critical to device operation characteristics. Here we present a facile fabrication of high-efficiency PSCs based on compact, large-grain, pinhole-free CH3NH3PbI3-xBrx (MAPbI3-xBrx) thin films with high reproducibility. A simple methylammonium bromide (MABr) treatment via spin-coating with a proper MABr concentration converts MAPbI3 thin films with different initial film qualities (for example, grain size and pinholes) to high-quality MAPbI3-xBrx thin films following an Ostwald ripening process, which is strongly affected by MABr concentration and is ineffective when replacing MABr with methylammonium iodide. A higher MABr concentration enhances I-Br anion exchange reaction, yielding poorer device performance. This MABr-selective Ostwald ripening process improves cell efficiency but also enhances device stability and thus represents a simple, promising strategy for further improving PSC performance with higher reproducibility and reliability. PMID:27477212

  1. High Efficiency Furnace

    SciTech Connect

    Hwang, K. S.; Koestler, D. J.

    1985-08-27

    Disclosed is a dwelling furnace having at least one clam-shell type primary heat exchanger in parallel orientation with a secondary heat exchanger, both the primary and secondary heat exchangers being vertically oriented relative to a furnace housing and parallel to the flow of air to be heated. The primary heat exchanger has a combustion chamber in the lower end thereof, and the lower end of the secondary heat exchanger exhausts into a tertiary heat exchanger oriented approximately perpendicular to the primary and secondary heat exchangers and horizontally relative to the housing, below the combustion chambers of the primary heat exchangers and below the exhaust outlet of the secondary heat exchanger. The tertiary heat exchanger includes a plurality of condensation tubes for retrieving the latent heat of condensation of the combustion gases. The furnace further comprises an induced draft blower for drawing combustion gases through the heat exchangers and inducting sufficient air to the combustion chamber of the primary heat exchanger for efficient combustion.

  2. High efficiency furnace

    SciTech Connect

    Hwang, K. S.; Koestler, D. J.

    1985-12-31

    Disclosed is a dwelling furnace having at least one clam-shell type primary heat exchanger in parallel orientation with a secondary heat exchanger, both the primary and secondary heat exchangers being vertically oriented relative to a furnace housing and parallel to the flow of air to be heated. The primary heat exchanger has a combustion chamber in the lower end thereof, and the lower end of the secondary heat exchanger exhausts into a tertiary heat exchanger oriented approximately perpendicular to the primary and secondary heat exchangers and horizontally relative to the housing, below the combustion chambers of the primary heat exchangers and below the exhaust outlet of the secondary heat exchanger. The tertiary heat exchanger includes a plurality of condensation tubes for retrieving the latent heat of condensation of the combustion gases. The furnace further comprises an induced draft blower for drawing combustion gases through the heat exchangers and inducting sufficient air to the combustion chamber of the primary heat exchanger for efficient combustion.

  3. HPF HIGH PRESSURE FACILITY GAS ANALYSIS SYSTEM IN BASEMENT / HIGH TEMPERATURE GAS FACILITY IN THE E

    NASA Technical Reports Server (NTRS)

    1980-01-01

    HPF HIGH PRESSURE FACILITY GAS ANALYSIS SYSTEM IN BASEMENT / HIGH TEMPERATURE GAS FACILITY IN THE ENGINE RESEARCH BUILDING ERB TEST CELL CE-13 / AUTOMATIC SCAN VALUE SYSTEM ON THE SECOND FLOOR OF THE INSTRUMENT RESEARCH LABORATORY IRL

  4. High efficiency gas burner

    DOEpatents

    Schuetz, Mark A.

    1983-01-01

    A burner assembly provides for 100% premixing of fuel and air by drawing the air into at least one high velocity stream of fuel without power assist. Specifically, the nozzle assembly for injecting the fuel into a throat comprises a plurality of nozzles in a generally circular array. Preferably, swirl is imparted to the air/fuel mixture by angling the nozzles. The diffuser comprises a conical primary diffuser followed by a cusp diffuser.

  5. Energy-Efficient Design for Florida Educational Facilities.

    ERIC Educational Resources Information Center

    Florida Solar Energy Center, Cape Canaveral.

    This manual provides a detailed simulation analysis of a variety of energy conservation measures (ECMs) with the intent of giving educational facility design teams in Florida a basis for decision making. The manual's three sections cover energy efficiency design considerations that appear throughout the following design processes: schematic…

  6. A facile one-pot method to synthesize a three-dimensional graphene@carbon nanotube composite as a high-efficiency microwave absorber.

    PubMed

    Wang, Lei; Huang, Ying; Li, Chao; Chen, Junjiao; Sun, Xu

    2015-01-21

    A novel three-dimensional graphene@carbon nanotube (CNTs) composite has been prepared using a facile one-pot pyrolysis strategy using urea as the carbon source, in which the density and length of CNTs on graphene are rationally tuned by adding an appropriate amount of urea to a precursor mixture. Correspondingly, the density and length of CNTs on graphene have a significant effect on the microwave absorption properties of graphene@CNTs. When most of the graphene surface is clearly covered by the CNTs whose length ranges from 300 to 600 nm, the graphene@CNT composite exhibits excellent microwave absorption properties. The maximum reflection loss value can reach -44.6 dB at 8.6 GHz and the absorption bandwidth with a reflection loss below -10 dB ranges from 7.1 to 10.4 GHz with an addition amount of only 5 wt% graphene@CNTs composite in the paraffin matrix.

  7. Facile "living" radical polymerization of methyl methacrylate in the presence of iniferter agents: homogeneous and highly efficient catalysis from copper(II) acetate.

    PubMed

    Jiang, Hongjuan; Zhang, Lifen; Jiang, Xiaowu; Bao, Xiaoguang; Cheng, Zhenping; Zhu, Xiulin

    2014-08-01

    A facile homogeneous polymerization system involving the iniferter agent 1-cyano-1-methylethyl diethyldithiocarbamate (MANDC) and copper(II) acetate (Cu(OAc)2 ) is successfully developed in bulk using methyl methacylate (MMA) as a model monomer. The detailed polymerization kinetics with different molar ratios (e.g., [MMA]0 /[MANDC]0 /[Cu(OAc)2 ]0 = 500/1/x (x = 0.1, 0.2, 0.5, 1.0)) demonstrate that this system has the typical "living"/controlled features of "living" radical polymerization, even with ppm level catalyst Cu(OAc)2 , first order polymerization kinetics, a linear increase in molecular weight with monomer conversion and narrow molecular weight distributions for the resultant PMMA. (1) H NMR spectra and chain-extension experiments further confirm the "living" characteristics of this process. A plausible mechanism is discussed.

  8. Test facility for high pressure plasmas

    SciTech Connect

    Block, R.; Laroussi, M.; Schoenbach, K.H.

    1999-07-01

    High pressure nonthermal plasmas are gaining increasing importance because of their wide range of applications, e.g. in air plasma ramparts, gas processing, surface treatment, thin film deposition, and chemical and biological decontamination. In order to compare various methods of plasma generation with respect to efficiency, development of instabilities, homogeneity, lifetime etc., a central test facility for high pressure plasmas is being established. The facility will allow one to study large volume (> 100 cm{sup 3}), nonthermal (gas temperature: < 2,000 K) plasmas over a large pressure range (10{sup {minus}6} Torr up to more than 1 atmosphere) in a standardized discharge cell. The setup was designed to generate plasmas in air as well as in gas mixtures. The available voltage range extends to 25 kV dc (10 kW power). The electrodes can be water cooled. Electrical diagnostics include a 400 Mhz, 2 GS/s 4-channel oscilloscope for current and voltage measurements and the detection of the onset of instabilities. For optical diagnostics, a CCD video camera is used to record the appearance of dc discharges. A high-speed light intensified CCD-camera (25 mm MCP with photocathode, gating speed: 200 ps, adjustable in 10 ps steps) allows to study the development of instabilities and can also be utilized in temporally resolved spectroscopic measurements. Optical emission spectroscopy allows one to determine plasma parameters such as electron density (through Stark broadening measurements) and gas temperature measurements. Interferometry is well suited for electron density measurements especially in weakly ionized plasmas.

  9. High efficiency solar cell processing

    NASA Technical Reports Server (NTRS)

    Ho, F.; Iles, P. A.

    1985-01-01

    At the time of writing, cells made by several groups are approaching 19% efficiency. General aspects of the processing required for such cells are discussed. Most processing used for high efficiency cells is derived from space-cell or concentrator cell technology, and recent advances have been obtained from improved techniques rather than from better understanding of the limiting mechanisms. Theory and modeling are fairly well developed, and adequate to guide further asymptotic increases in performance of near conventional cells. There are several competitive cell designs with promise of higher performance ( 20%) but for these designs further improvements are required. The available cell processing technology to fabricate high efficiency cells is examined.

  10. Energy Efficiency Strategies for Municipal Wastewater Treatment Facilities

    SciTech Connect

    Daw, J.; Hallett, K.; DeWolfe, J.; Venner, I.

    2012-01-01

    Water and wastewater systems are significant energy consumers with an estimated 3%-4% of total U.S. electricity consumption used for the movement and treatment of water and wastewater. Water-energy issues are of growing importance in the context of water shortages, higher energy and material costs, and a changing climate. In this economic environment, it is in the best interest for utilities to find efficiencies, both in water and energy use. Performing energy audits at water and wastewater treatment facilities is one way community energy managers can identify opportunities to save money, energy, and water. In this paper the importance of energy use in wastewater facilities is illustrated by a case study of a process energy audit performed for Crested Butte, Colorado's wastewater treatment plant. The energy audit identified opportunities for significant energy savings by looking at power intensive unit processes such as influent pumping, aeration, ultraviolet disinfection, and solids handling. This case study presents best practices that can be readily adopted by facility managers in their pursuit of energy and financial savings in water and wastewater treatment. This paper is intended to improve community energy managers understanding of the role that the water and wastewater sector plays in a community's total energy consumption. The energy efficiency strategies described provide information on energy savings opportunities, which can be used as a basis for discussing energy management goals with water and wastewater treatment facility managers.

  11. Sultan - forced flow, high field test facility

    SciTech Connect

    Horvath, I.; Vecsey, G.; Weymuth, P.; Zellweger, J.

    1981-09-01

    Three European laboratories: CNEN (Frascati, I) ECN (Petten, NL) and SIN (Villigen, CH) decided to coordinate their development efforts and to install a common high field forced flow test facility at Villigen Switzerland. The test facility SULTAN (Supraleiter Testanlage) is presently under construction. As a first step, an 8T/1m bore solenoid with cryogenic periphery will be ready in 1981. The cryogenic system, data acquisition system and power supplies which are contributed by SIN are described. Experimental feasibilities, including cooling, and instrumentation are reviewed. Progress of components and facility construction is described. Planned extension of the background field up to 12T by insert coils is outlined. 5 refs.

  12. High efficiency SPS klystron design

    NASA Technical Reports Server (NTRS)

    Nalos, E. J.

    1980-01-01

    The most likely compact configuration to realize both high efficiency and high gain (approx. 40 dB) is a 5-6 cavity design focused by an electromagnet. The basic klystron efficiency cannot be expected to exceed 70-75% without collector depression. It was estimated that the net benefit of a 5 stage collector over a 2 stage collector is between 1.5 and 3.5 kW per tube. A modulating anode is incorporated in the design to enable rapid shutoff of the beam current in case the r.f. drive should be removed.

  13. High efficiency solar panel /HESP/

    NASA Technical Reports Server (NTRS)

    Stella, P. M.; Gay, C.; Uno, F.; Scott-Monck, J.

    1978-01-01

    A family of high efficiency, weldable silicon solar cells, incorporating nearly every feature of advanced cell technology developed in the past four years, was produced and subjected to space qualification testing. This matrix contained both field and non-field cells ranging in thickness from 0.10 mm to 0.30 mm, and in base resistivity from nominal two to one hundred ohm-cm. Initial power outputs as high as 20 mW/sq cm (14.8% AM0 efficiency) were produced by certain cell types within the matrix.

  14. High intensity neutrino oscillation facilities in Europe

    NASA Astrophysics Data System (ADS)

    Edgecock, T. R.; Caretta, O.; Davenne, T.; Densam, C.; Fitton, M.; Kelliher, D.; Loveridge, P.; Machida, S.; Prior, C.; Rogers, C.; Rooney, M.; Thomason, J.; Wilcox, D.; Wildner, E.; Efthymiopoulos, I.; Garoby, R.; Gilardoni, S.; Hansen, C.; Benedetto, E.; Jensen, E.; Kosmicki, A.; Martini, M.; Osborne, J.; Prior, G.; Stora, T.; Melo Mendonca, T.; Vlachoudis, V.; Waaijer, C.; Cupial, P.; Chancé, A.; Longhin, A.; Payet, J.; Zito, M.; Baussan, E.; Bobeth, C.; Bouquerel, E.; Dracos, M.; Gaudiot, G.; Lepers, B.; Osswald, F.; Poussot, P.; Vassilopoulos, N.; Wurtz, J.; Zeter, V.; Bielski, J.; Kozien, M.; Lacny, L.; Skoczen, B.; Szybinski, B.; Ustrycka, A.; Wroblewski, A.; Marie-Jeanne, M.; Balint, P.; Fourel, C.; Giraud, J.; Jacob, J.; Lamy, T.; Latrasse, L.; Sortais, P.; Thuillier, T.; Mitrofanov, S.; Loiselet, M.; Keutgen, Th.; Delbar, Th.; Debray, F.; Trophine, C.; Veys, S.; Daversin, C.; Zorin, V.; Izotov, I.; Skalyga, V.; Burt, G.; Dexter, A. C.; Kravchuk, V. L.; Marchi, T.; Cinausero, M.; Gramegna, F.; De Angelis, G.; Prete, G.; Collazuol, G.; Laveder, M.; Mazzocco, M.; Mezzetto, M.; Signorini, C.; Vardaci, E.; Di Nitto, A.; Brondi, A.; La Rana, G.; Migliozzi, P.; Moro, R.; Palladino, V.; Gelli, N.; Berkovits, D.; Hass, M.; Hirsh, T. Y.; Schaumann, M.; Stahl, A.; Wehner, J.; Bross, A.; Kopp, J.; Neuffer, D.; Wands, R.; Bayes, R.; Laing, A.; Soler, P.; Agarwalla, S. K.; Cervera Villanueva, A.; Donini, A.; Ghosh, T.; Gómez Cadenas, J. J.; Hernández, P.; Martín-Albo, J.; Mena, O.; Burguet-Castell, J.; Agostino, L.; Buizza-Avanzini, M.; Marafini, M.; Patzak, T.; Tonazzo, A.; Duchesneau, D.; Mosca, L.; Bogomilov, M.; Karadzhov, Y.; Matev, R.; Tsenov, R.; Akhmedov, E.; Blennow, M.; Lindner, M.; Schwetz, T.; Fernández Martinez, E.; Maltoni, M.; Menéndez, J.; Giunti, C.; González García, M. C.; Salvado, J.; Coloma, P.; Huber, P.; Li, T.; López Pavón, J.; Orme, C.; Pascoli, S.; Meloni, D.; Tang, J.; Winter, W.; Ohlsson, T.; Zhang, H.; Scotto-Lavina, L.; Terranova, F.; Bonesini, M.; Tortora, L.; Alekou, A.; Aslaninejad, M.; Bontoiu, C.; Kurup, A.; Jenner, L. J.; Long, K.; Pasternak, J.; Pozimski, J.; Back, J. J.; Harrison, P.; Beard, K.; Bogacz, A.; Berg, J. S.; Stratakis, D.; Witte, H.; Snopok, P.; Bliss, N.; Cordwell, M.; Moss, A.; Pattalwar, S.; Apollonio, M.

    2013-02-01

    The EUROnu project has studied three possible options for future, high intensity neutrino oscillation facilities in Europe. The first is a Super Beam, in which the neutrinos come from the decay of pions created by bombarding targets with a 4 MW proton beam from the CERN High Power Superconducting Proton Linac. The far detector for this facility is the 500 kt MEMPHYS water Cherenkov, located in the Fréjus tunnel. The second facility is the Neutrino Factory, in which the neutrinos come from the decay of μ+ and μ- beams in a storage ring. The far detector in this case is a 100 kt magnetized iron neutrino detector at a baseline of 2000 km. The third option is a Beta Beam, in which the neutrinos come from the decay of beta emitting isotopes, in particular He6 and Ne18, also stored in a ring. The far detector is also the MEMPHYS detector in the Fréjus tunnel. EUROnu has undertaken conceptual designs of these facilities and studied the performance of the detectors. Based on this, it has determined the physics reach of each facility, in particular for the measurement of CP violation in the lepton sector, and estimated the cost of construction. These have demonstrated that the best facility to build is the Neutrino Factory. However, if a powerful proton driver is constructed for another purpose or if the MEMPHYS detector is built for astroparticle physics, the Super Beam also becomes very attractive.

  15. High Efficiency Engine Technologies Program

    SciTech Connect

    Rich Kruiswyk

    2010-07-13

    Caterpillar's Product Development and Global Technology Division carried out a research program on waste heat recovery with support from DOE (Department of Energy) and the DOE National Energy Technology Laboratory. The objective of the program was to develop a new air management and exhaust energy recovery system that would demonstrate a minimum 10% improvement in thermal efficiency over a base heavy-duty on-highway diesel truck engine. The base engine for this program was a 2007 C15 15.2L series-turbocharged on-highway truck engine with a LPL (low-pressure loop) exhaust recirculation system. The focus of the program was on the development of high efficiency turbomachinery and a high efficiency turbocompound waste heat recovery system. The focus of each area of development was as follows: (1) For turbine stages, the focus was on investigation and development of technologies that would improve on-engine exhaust energy utilization compared to the conventional radial turbines in widespread use today. (2) For compressor stages, the focus was on investigating compressor wheel design parameters beyond the range typically utilized in production, to determine the potential efficiency benefits thereof. (3) For turbocompound, the focus was on the development of a robust bearing system that would provide higher bearing efficiencies compared to systems used in turbocompound power turbines in production. None of the turbocharger technologies investigated involved addition of moving parts, actuators, or exotic materials, thereby increasing the likelihood of a favorable cost-value tradeoff for each technology. And the turbocompound system requires less hardware addition than competing bottoming cycle technologies, making it a more attractive solution from a cost and packaging standpoint. Main outcomes of the program are as follows: (1) Two turbine technologies that demonstrated up to 6% improvement in turbine efficiency on gas stand and 1-3% improvement in thermal efficiency in

  16. Enabling High Efficiency Ethanol Engines

    SciTech Connect

    Szybist, J.; Confer, K.

    2011-03-01

    Delphi Automotive Systems and ORNL established this CRADA to explore the potential to improve the energy efficiency of spark-ignited engines operating on ethanol-gasoline blends. By taking advantage of the fuel properties of ethanol, such as high compression ratio and high latent heat of vaporization, it is possible to increase efficiency with ethanol blends. Increasing the efficiency with ethanol-containing blends aims to remove a market barrier of reduced fuel economy with E85 fuel blends, which is currently about 30% lower than with petroleum-derived gasoline. The same or higher engine efficiency is achieved with E85, and the reduction in fuel economy is due to the lower energy density of E85. By making ethanol-blends more efficient, the fuel economy gap between gasoline and E85 can be reduced. In the partnership between Delphi and ORNL, each organization brought a unique and complementary set of skills to the project. Delphi has extensive knowledge and experience in powertrain components and subsystems as well as overcoming real-world implementation barriers. ORNL has extensive knowledge and expertise in non-traditional fuels and improving engine system efficiency for the next generation of internal combustion engines. Partnering to combine these knowledge bases was essential towards making progress to reducing the fuel economy gap between gasoline and E85. ORNL and Delphi maintained strong collaboration throughout the project. Meetings were held regularly, usually on a bi-weekly basis, with additional reports, presentations, and meetings as necessary to maintain progress. Delphi provided substantial hardware support to the project by providing components for the single-cylinder engine experiments, engineering support for hardware modifications, guidance for operational strategies on engine research, and hardware support by providing a flexible multi-cylinder engine to be used for optimizing engine efficiency with ethanol-containing fuels.

  17. High pressure turbomachinery ground test facility

    NASA Technical Reports Server (NTRS)

    Scheuermann, Patrick E.

    1992-01-01

    Turbomachinery test facilities are at present scarce to non-existent world-wide. The turbomachinery test facility at Stennis Space Center will provide for advanced development and research and development capabilities for liquid hydrogen/liquid oxygen propellant rocket engine components. The facility will provide ultra-high pressure via gas generators to deliver the needed turbine drive on various turbomachinery. State of the art process control systems will provide the vital pressure, temperature and flow requirements during tests. These systems will better control adverse transient conditions during start-up and shutdown, and by using advanced control theory, as well as incorporate test article health monitoring. Also, digital data acquisition systems will obtain high frequency (up to 20 KHz) and low frequency (up to 1 KHz) data during the test. Pressures of up to 15,000 psi will be generated to pressurize high pressure tanks supplying cryogens to various test article inlets thus pushing turbopump materials and manufacturing processes to their limits. By planning for future projects the test facility will be easily adaptable to multi-program test configurations over a range of thermodynamic positions.

  18. High magnetic field facilities in Latin America

    NASA Astrophysics Data System (ADS)

    Sato, R.; Grössinger, R.; Bertorello, H.; Broto, J. M.; Davies, H. A.; Estevez-Rams, E.; Gonzalez, J.; Matutes, J.; Sinnecker, J. P.; Sagredo, V.

    2006-11-01

    The EC supported a network (under the Framework 5 ALFA Programme) designated HIFIELD (Project number II0147FI) and entitled: "Measurement methods involving high magnetic fields for advanced and novel materials". As a result, high field facilities were initiated, constructed or extended at the following laboratories in Latin America: University Cordoba (Argentina), CES, Merida (Venezuela), CIMAV, Chihuahua (Mexico), University Federal de Rio de Janeiro (Brazil).

  19. Test facilities for high power electric propulsion

    NASA Technical Reports Server (NTRS)

    Sovey, James S.; Vetrone, Robert H.; Grisnik, Stanley P.; Myers, Roger M.; Parkes, James E.

    1991-01-01

    Electric propulsion has applications for orbit raising, maneuvering of large space systems, and interplanetary missions. These missions involve propulsion power levels from tenths to tens of megawatts, depending upon the application. General facility requirements for testing high power electric propulsion at the component and thrust systems level are defined. The characteristics and pumping capabilities of many large vacuum chambers in the United States are reviewed and compared with the requirements for high power electric propulsion testing.

  20. High Efficiency Room Air Conditioner

    SciTech Connect

    Bansal, Pradeep

    2015-01-01

    This project was undertaken as a CRADA project between UT-Battelle and Geberal Electric Company and was funded by Department of Energy to design and develop of a high efficiency room air conditioner. A number of novel elements were investigated to improve the energy efficiency of a state-of-the-art WAC with base capacity of 10,000 BTU/h. One of the major modifications was made by downgrading its capacity from 10,000 BTU/hr to 8,000 BTU/hr by replacing the original compressor with a lower capacity (8,000 BTU/hr) but high efficiency compressor having an EER of 9.7 as compared with 9.3 of the original compressor. However, all heat exchangers from the original unit were retained to provide higher EER. The other subsequent major modifications included- (i) the AC fan motor was replaced by a brushless high efficiency ECM motor along with its fan housing, (ii) the capillary tube was replaced with a needle valve to better control the refrigerant flow and refrigerant set points, and (iii) the unit was tested with a drop-in environmentally friendly binary mixture of R32 (90% molar concentration)/R125 (10% molar concentration). The WAC was tested in the environmental chambers at ORNL as per the design rating conditions of AHAM/ASHRAE (Outdoor- 95F and 40%RH, Indoor- 80F, 51.5%RH). All these modifications resulted in enhancing the EER of the WAC by up to 25%.

  1. Very high-vacuum heat treatment facility

    NASA Technical Reports Server (NTRS)

    Folkner, W. M.; Moody, M. V.; Richard, J.-P.

    1987-01-01

    A vacuum heat treatment facility, with hot zone dimensions of 12 x 19 x 19 cm, has been designed and constructed at a cost substantially below that of a commercial unit. The design incorporates efficient water cooling and a resistive heating element. A vacuum pressure of 1.5 x 10 to the -8th torr at room temperature has been obtained after baking. The temperature limit is approximately 1900 C. This limit results from the choice of niobium as the hot zone material.

  2. A simple, high efficiency, high resolution spectropolarimeter

    NASA Astrophysics Data System (ADS)

    Barden, Samuel C.

    2012-09-01

    A simple concept is described that uses volume phase holographic gratings as polarizing dispersers for a high efficiency, high resolution spectropolarimeter. Although the idea has previously been mentioned in the literature as possible, such a concept has not been explored in detail. Performance analysis is presented for a VPHG spectropolarimeter concept that could be utilized for both solar and night-time astronomy. Instrumental peak efficiency can approach 100% with spectral dispersions permitting R~200,000 spectral resolution with diffraction limited telescopes. The instrument has 3-channels: two dispersed image planes with orthogonal polarization and an undispersed image plane. The concept has a range of versatility where it could be configured (with appropriate half-wave plates) for slit-fed spectroscopy or without slits for snapshot/hyperspectral/tomographic spectroscopic imaging. Multiplex gratings could also be used for the simultaneous recording of two separate spectral bands or multiple instruments could be daisy chained with beam splitters for further spectral coverage.

  3. High Efficiency Germanium Immersion Gratings

    SciTech Connect

    Kuzmenko, P J; Davis, P J; Little, S L; Little, L M; Bixler, J V

    2006-05-01

    We have fabricated several germanium immersion gratings by single crystal, single point diamond flycutting on an ultra-precision lathe. Use of a dead sharp tool produces groove corners less than 0.1 micron in radius and consequently high diffraction efficiency. We measured first order efficiencies in immersion of over 80% at 10.6 micron wavelength. Wavefront error was low averaging 0.06 wave rms (at 633 nm) across the full aperture. The grating spectral response was free of ghosts down to our detection limit of 1 part in 10{sup 4}. Scatter should be low based upon the surface roughness. Measurement of the spectral line profile of a CO{sub 2} laser sets an upper bound on total integrated scatter of 0.5%.

  4. High Performance Imaging Streak Camera for the National Ignition Facility

    SciTech Connect

    Opachich, Y. P.; Kalantar, D.; MacPhee, A.; Holder, J.; Kimbrough, J.; Bell, P. M.; Bradley, D.; Hatch, B.; Brown, C.; Landen, O.; Perfect, B. H.; Guidry, B.; Mead, A.; Charest, M.; Palmer, N.; Homoelle, D.; Browning, D.; Silbernagel, C.; Brienza-Larsen, G.; Griffin, M.; Lee, J. J.; Haugh, M. J.

    2012-01-01

    An x-ray streak camera platform has been characterized and implemented for use at the National Ignition Facility. The camera has been modified to meet the experiment requirements of the National Ignition Campaign and to perform reliably in conditions that produce high EMI. A train of temporal UV timing markers has been added to the diagnostic in order to calibrate the temporal axis of the instrument and the detector efficiency of the streak camera was improved by using a CsI photocathode. The performance of the streak camera has been characterized and is summarized in this paper. The detector efficiency and cathode measurements are also presented.

  5. High-efficiency photovoltaic cells

    DOEpatents

    Yang, H.T.; Zehr, S.W.

    1982-06-21

    High efficiency solar converters comprised of a two cell, non-lattice matched, monolithic stacked semiconductor configuration using optimum pairs of cells having bandgaps in the range 1.6 to 1.7 eV and 0.95 to 1.1 eV, and a method of fabrication thereof, are disclosed. The high band gap subcells are fabricated using metal organic chemical vapor deposition (MOCVD), liquid phase epitaxy (LPE) or molecular beam epitaxy (MBE) to produce the required AlGaAs layers of optimized composition, thickness and doping to produce high performance, heteroface homojunction devices. The low bandgap subcells are similarly fabricated from AlGa(As)Sb compositions by LPE, MBE or MOCVD. These subcells are then coupled to form a monolithic structure by an appropriate bonding technique which also forms the required transparent intercell ohmic contact (IOC) between the two subcells. Improved ohmic contacts to the high bandgap semiconductor structure can be formed by vacuum evaporating to suitable metal or semiconductor materials which react during laser annealing to form a low bandgap semiconductor which provides a low contact resistance structure.

  6. High precision Woelter optic calibration facility

    SciTech Connect

    Morales, R.I.; Remington, B.A.; Schwinn, T.

    1994-05-02

    We have developed an off-line facility for very precise characterization of the reflectance and spatial resolution of the grazing incidence Woelter Type 1 x-ray optics used at Nova. The primary component of the facility is a high brightness, ``point`` x-ray source consisting of a focussed DC electron beam incident onto a precision manipulated target/pinhole array. The data are recorded with a selection of detectors. For imaging measurements we use direct exposure x-ray film modules or an x-ray CCD camera. For energy-resolved reflectance measurements, we use lithium drifted silicon detectors and a proportional counter. An in situ laser alignment system allows precise location and rapid periodic alignment verification of the x-ray point source, the statically mounted Woelter optic, and the chosen detector.

  7. High efficiency shale oil recovery

    SciTech Connect

    Adams, C.D.

    1992-07-18

    The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated at bench-scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although an oil shale batch sample is sealed in the batch kiln from the start until the end of the run, the process conditions for the batch are the same as the conditions that an element of oil shale would encounter in a larger continuous process kiln. For example, similar conditions of heatup rate, oxidation of the residue and cool-down prevail for the element in both systems. This batch kiln is a unit constructed in a 1987 Phase I SBIR tar sand retorting project. The kiln worked fairly well in that project; however, the need for certain modifications was observed. These modifications are now underway to simplify the operation and make the data and analysis more exact. The second quarter agenda consisted of (a) kiln modifications; (b) sample preparation; and (c) Heat Transfer calibration runs (part of proposal task number 3 -- to be completed by the end of month 7).

  8. High efficiency laser spectrum conditioner

    DOEpatents

    Greiner, Norman R.

    1980-01-01

    A high efficiency laser spectrum conditioner for generating a collinear parallel output beam containing a predetermined set of frequencies from a multifrequency laser. A diffraction grating and spherical mirror are used in combination, to disperse the various frequencies of the input laser beam and direct these frequencies along various parallel lines spatially separated from one another to an apertured mask. Selection of the desired frequencies is accomplished by placement of apertures at locations on the mask where the desired frequencies intersect the mask. A recollimated parallel output beam with the desired set of frequencies is subsequently generated utilizing a mirror and grating matched and geometrically aligned in the same manner as the input grating and mirror.

  9. High-temperature helium-loop facility

    SciTech Connect

    Tokarz, R.D.

    1981-09-01

    The high-temperature helium loop is a facility for materials testing in ultrapure helium gas at high temperatures. The closed loop system is capable of recirculating high-purity helium or helium with controlled impurities. The gas loop maximum operating conditions are as follows: 300 psi pressure, 500 lb/h flow rate, and 2100/sup 0/F temperature. The two test sections can accept samples up to 3.5 in. diameter and 5 ft long. The gas loop is fully instrumented to continuously monitor all parameters of loop operation as well as helium impurities. The loop is fully automated to operate continuously and requires only a daily servicing by a qualified operator to replenish recorder charts and helium makeup gas. Because of its versatility and high degree of parameter control, the helium loop is applicable to many types of materials research. This report describes the test apparatus, operating parameters, peripheral systems, and instrumentation system.

  10. High efficiency shale oil recovery

    SciTech Connect

    Adams, D.C.

    1992-01-01

    The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated at bench-scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although a batch oil shale sample will be sealed in the batch kiln from the start until the end of the run, the process conditions for the batch will be the same as the conditions that an element of oil shale would encounter in a large continuous process kiln. For example, similar conditions of heat-up rate (20 deg F/min during the pyrolysis), oxidation of the residue and cool-down will prevail for the element in both systems. This batch kiln is a unit constructed in a 1987 Phase I SBIR tar sand retorting project. The kiln worked fairly well in that project; however, the need for certain modifications was observed. These modifications are now underway to simplify the operation and make the data and analysis more exact. The agenda for the first three months of the project consisted of the first of nine tasks and was specified as the following four items: 1. Sample acquisition and equipment alteration: Obtain seven oil shale samples, of varying grade each 10 lb or more, and samples of quartz sand. Order equipment for kiln modification. 3. Set up and modify kiln for operation, including electric heaters on the ends of the kiln. 4. Connect data logger and make other repairs and changes in rotary batch kiln.

  11. High efficiency shale oil recovery

    SciTech Connect

    Adams, D.C.

    1993-04-22

    The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated on a small scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although an oil shale batch sample is sealed in the batch kiln from the start until the end of the run, the process conditions for the batch are the same as the conditions that an element of oil shale would encounter in a continuous process kiln. Similar chemical and physical conditions (heating, mixing, pyrolysis, oxidation) exist in both systems.The two most important data objectives in this phase of the project are to demonstrate (1) that the heat recovery projected for this project is reasonable and (2) that an oil shale kiln will run well and not plug up due to sticking and agglomeration. The following was completed this quarter. (1) Twelve pyrolysis runs were made on five different oil shales. All of the runs exhibited a complete absence of any plugging, tendency. Heat transfer for Green River oil shale in the rotary kiln was 84.6 Btu/hr/ft[sup 2]/[degrees]F, and this will provide for ample heat exchange in the Adams kiln. (2) One retorted residue sample was oxidized at 1000[degrees]F. Preliminary indications are that the ash of this run appears to have been completely oxidized. (3) Further minor equipment repairs and improvements were required during the course of the several runs.

  12. High efficiency shale oil recovery

    SciTech Connect

    Adams, D.C.

    1992-01-01

    The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated on a small scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although an oil shale batch sample is sealed in the batch kiln from the start until the end of the run, the process conditions for the batch are the same as the conditions that an element of oil shale would encounter in a continuous process kiln. Similar chemical and physical (heating, mixing) conditions exist in both systems. The two most important data objectives in this phase of the project are to demonstrate (1) that the heat recovery projected for this project is reasonable and (2) that an oil shale kiln will run well and not plug up due to sticking and agglomeration. The following was completed and is reported on this quarter: (1) A software routine was written to eliminate intermittently inaccurate temperature readings. (2) We completed the quartz sand calibration runs, resolving calibration questions from the 3rd quarter. (3) We also made low temperature retorting runs to identify the need for certain kiln modifications and kiln modifications were completed. (4) Heat Conductance data on two Pyrolysis runs were completed on two samples of Occidental oil shale.

  13. High temperature aircraft research furnace facilities

    NASA Technical Reports Server (NTRS)

    Smith, James E., Jr.; Cashon, John L.

    1992-01-01

    Focus is on the design, fabrication, and development of the High Temperature Aircraft Research Furnace Facilities (HTARFF). The HTARFF was developed to process electrically conductive materials with high melting points in a low gravity environment. The basic principle of operation is to accurately translate a high temperature arc-plasma gas front as it orbits around a cylindrical sample, thereby making it possible to precisely traverse the entire surface of a sample. The furnace utilizes the gas-tungsten-arc-welding (GTAW) process, also commonly referred to as Tungsten-Inert-Gas (TIG). The HTARFF was developed to further research efforts in the areas of directional solidification, float-zone processing, welding in a low-gravity environment, and segregation effects in metals. The furnace is intended for use aboard the NASA-JSC Reduced Gravity Program KC-135A Aircraft.

  14. High Efficiency Cascade Solar Cells

    SciTech Connect

    Shuguang Deng, Seamus Curran, Igor Vasiliev

    2010-09-28

    This report summarizes the main work performed by New Mexico State University and University of Houston on a DOE sponsored project High Efficiency Cascade Solar Cells. The main tasks of this project include materials synthesis, characterization, theoretical calculations, organic solar cell device fabrication and test. The objective of this project is to develop organic nano-electronic-based photovoltaics. Carbon nanotubes and organic conjugated polymers were used to synthesize nanocomposites as the new active semiconductor materials that were used for fabricating two device architectures: thin film coating and cascade solar cell fiber. Chemical vapor deposition technique was employed to synthesized a variety of carbon nanotubes (single-walled CNT, doubled-walled CNT, multi-walled CNT, N-doped SWCNT, DWCNT and MWCNT, and B-doped SWCNT, DWCNT and MWCNT) and a few novel carbon structures (CNT-based nanolance, nanocross and supported graphene film) that have potential applications in organic solar cells. Purification procedures were developed for removing amorphous carbons from carbon nanotubes, and a controlled oxidation method was established for partial truncation of fullerene molecules. Carbon nanotubes (DWCNT and DWCNT) were functionalized with fullerenes and dyes covalently and used to form nanocomposites with conjugated polymers. Biologically synthesized Tellurium nanotubes were used to form composite with the conjugated polymers as well, which generated the highest reported optical limiting values from composites. Several materials characterization technique including SEM/TEM, Raman, AFM, UV-vis, adsorption and EDS were employed to characterize the physical and chemical properties of the carbon nanotubes, the functionalized carbon nanotubes and the nanocomposites synthesized in this project. These techniques allowed us to have a spectroscopic and morphological control of the composite formation and to understand the materials assembled. A parallel 136-CPU

  15. Highly efficient welding power supply

    NASA Astrophysics Data System (ADS)

    Thommes, J. M.

    1980-09-01

    The results and findings of an energy efficient welding power development project are presented. The power source developed is to be used for electric arc welding processes in which 3.5 trillion Btu of energy can be saved annually. The power source developed incorporates the use of switch mode power supply techniques in order to convert industrial supply mains to appropriate welding voltages and currents. A series capacitor switch mode power circuit was the circuit technique chosen in order to optimize energy efficiency, costs, reliability, size/weight, and welding performance. Test results demonstrated an effective efficiency (taking into account idle power consumption) of 80 to 91 percent for the energy efficient power source while the conventional types of power sources tested ranged from 41 to 74 percent efficiency. Line power factor was also improved for the energy efficient power source. Field tests indicated additional refinements of weld process performance and power source audible noise emission reduction could be beneficial.

  16. Numerical Simulations of High Enthalpy Pulse Facilities

    NASA Technical Reports Server (NTRS)

    Wilson, Gregory J.; Edwards, Thomas A. (Technical Monitor)

    1995-01-01

    Axisymmetric flows within shock tubes and expansion tubes are simulated including the effects of finite rate chemistry and both laminar and turbulent boundary layers. The simulations demonstrate the usefulness of computational fluid dynamics for characterizing the flows in high enthalpy pulse facilities. The modeling and numerical requirements necessary to simulate these flows accurately are also discussed. Although there is a large body of analysis which explains and quantifies the boundary layer growth between the shock and the interface in a shock tube, there is a need for more detailed solutions. Phenomena such as thermochemical nonequilibrium. or turbulent transition behind the shock are excluded in the assumptions of Mirels' analysis. Additionally there is inadequate capability to predict the influence of the boundary layer on the expanded gas behind the interface. Quantifying the gas in this region is particularly important in expansion tubes because it is the location of the test gas. Unsteady simulations of the viscous flow in shock tubes are computationally expensive because they must follow features such as a shock wave over the length of the facility and simultaneously resolve the small length scales within the boundary layer. As a result, efficient numerical algorithms are required. The numerical approach of the present work is to solve the axisymmetric gas dynamic equations using an finite-volume formulation where the inviscid fluxes are computed with a upwind TVD scheme. Multiple species equations are included in the formulation so that finite-rate chemistry can be modeled. The simulations cluster grid points at the shock and interface and translate this clustered grid with these features to minimize numerical errors. The solutions are advanced at a CFL number of less than one based on the inviscid gas dynamics. To avoid limitations on the time step due to the viscous terms, these terms are treated implicitly. This requires a block tri

  17. High efficiency, long life terrestrial solar panel

    NASA Technical Reports Server (NTRS)

    Chao, T.; Khemthong, S.; Ling, R.; Olah, S.

    1977-01-01

    The design of a high efficiency, long life terrestrial module was completed. It utilized 256 rectangular, high efficiency solar cells to achieve high packing density and electrical output. Tooling for the fabrication of solar cells was in house and evaluation of the cell performance was begun. Based on the power output analysis, the goal of a 13% efficiency module was achievable.

  18. High efficiency turbine blade coatings.

    SciTech Connect

    Youchison, Dennis L.; Gallis, Michail A.

    2014-06-01

    The development of advanced thermal barrier coatings (TBCs) of yttria stabilized zirconia (YSZ) that exhibit lower thermal conductivity through better control of electron beam - physical vapor deposition (EB-PVD) processing is of prime interest to both the aerospace and power industries. This report summarizes the work performed under a two-year Lab-Directed Research and Development (LDRD) project (38664) to produce lower thermal conductivity, graded-layer thermal barrier coatings for turbine blades in an effort to increase the efficiency of high temperature gas turbines. This project was sponsored by the Nuclear Fuel Cycle Investment Area. Therefore, particular importance was given to the processing of the large blades required for industrial gas turbines proposed for use in the Brayton cycle of nuclear plants powered by high temperature gas-cooled reactors (HTGRs). During this modest (~1 full-time equivalent (FTE)) project, the processing technology was developed to create graded TBCs by coupling ion beam-assisted deposition (IBAD) with substrate pivoting in the alumina-YSZ system. The Electron Beam - 1200 kW (EB-1200) PVD system was used to deposit a variety of TBC coatings with micron layered microstructures and reduced thermal conductivity below 1.5 W/m.K. The use of IBAD produced fully stoichiometric coatings at a reduced substrate temperature of 600 oC and a reduced oxygen background pressure of 0.1 Pa. IBAD was also used to successfully demonstrate the transitioning of amorphous PVD-deposited alumina to the -phase alumina required as an oxygen diffusion barrier and for good adhesion to the substrate Ni2Al3 bondcoat. This process replaces the time consuming thermally grown oxide formation required before the YSZ deposition. In addition to the process technology, Direct Simulation Monte Carlo plume modeling and spectroscopic characterization of the PVD plumes were performed. The project consisted of five tasks. These included the production of layered

  19. Efficiency and cost advantages of an advanced-technology nuclear electrolytic hydrogen-energy production facility

    NASA Technical Reports Server (NTRS)

    Donakowski, T. D.; Escher, W. J. D.; Gregory, D. P.

    1977-01-01

    The concept of an advanced-technology (viz., 1985 technology) nuclear-electrolytic water electrolysis facility was assessed for hydrogen production cost and efficiency expectations. The facility integrates (1) a high-temperature gas-cooled nuclear reactor (HTGR) operating a binary work cycle, (2) direct-current (d-c) electricity generation via acyclic generators, and (3) high-current-density, high-pressure electrolyzers using a solid polymer electrolyte (SPE). All subsystems are close-coupled and optimally interfaced for hydrogen production alone (i.e., without separate production of electrical power). Pipeline-pressure hydrogen and oxygen are produced at 6900 kPa (1000 psi). We found that this advanced facility would produce hydrogen at costs that were approximately half those associated with contemporary-technology nuclear electrolysis: $5.36 versus $10.86/million Btu, respectively. The nuclear-heat-to-hydrogen-energy conversion efficiency for the advanced system was estimated as 43%, versus 25% for the contemporary system.

  20. High Energy Efficiency Air Conditioning

    SciTech Connect

    Edward McCullough; Patrick Dhooge; Jonathan Nimitz

    2003-12-31

    This project determined the performance of a new high efficiency refrigerant, Ikon B, in a residential air conditioner designed to use R-22. The refrigerant R-22, used in residential and small commercial air conditioners, is being phased out of production in developed countries beginning this year because of concerns regarding its ozone depletion potential. Although a replacement refrigerant, R-410A, is available, it operates at much higher pressure than R-22 and requires new equipment. R-22 air conditioners will continue to be in use for many years to come. Air conditioning is a large part of expensive summer peak power use in many parts of the U.S. Previous testing and computer simulations of Ikon B indicated that it would have 20 - 25% higher coefficient of performance (COP, the amount of cooling obtained per energy used) than R-22 in an air-cooled air conditioner. In this project, a typical new R-22 residential air conditioner was obtained, installed in a large environmental chamber, instrumented, and run both with its original charge of R-22 and then with Ikon B. In the environmental chamber, controlled temperature and humidity could be maintained to obtain repeatable and comparable energy use results. Tests with Ikon B included runs with and without a power controller, and an extended run for several months with subsequent analyses to check compatibility of Ikon B with the air conditioner materials and lubricant. Baseline energy use of the air conditioner with its original R-22 charge was measured at 90 deg F and 100 deg F. After changeover to Ikon B and a larger expansion orifice, energy use was measured at 90 deg F and 100 deg F. Ikon B proved to have about 19% higher COP at 90 deg F and about 26% higher COP at 100 deg F versus R-22. Ikon B had about 20% lower cooling capacity at 90 deg F and about 17% lower cooling capacity at 100 deg F versus R-22 in this system. All results over multiple runs were within 1% relative standard deviation (RSD). All of these

  1. High efficiency stationary hydrogen storage

    SciTech Connect

    Hynek, S.; Fuller, W.; Truslow, S.

    1995-09-01

    Stationary storage of hydrogen permits one to make hydrogen now and use it later. With stationary hydrogen storage, one can use excess electrical generation capacity to power an electrolyzer, and store the resultant hydrogen for later use or transshipment. One can also use stationary hydrogen as a buffer at fueling stations to accommodate non-steady fueling demand, thus permitting the hydrogen supply system (e.g., methane reformer or electrolyzer) to be sized to meet the average, rather than the peak, demand. We at ADL designed, built, and tested a stationary hydrogen storage device that thermally couples a high-temperature metal hydride to a phase change material (PCM). The PCM captures and stores the heat of the hydriding reaction as its own heat of fusion (that is, it melts), and subsequently returns that heat of fusion (by freezing) to facilitate the dehydriding reaction. A key component of this stationary hydrogen storage device is the metal hydride itself. We used nickel-coated magnesium powder (NCMP) - magnesium particles coated with a thin layer of nickel by means of chemical vapor deposition (CVD). Magnesium hydride can store a higher weight fraction of hydrogen than any other practical metal hydride, and it is less expensive than any other metal hydride. We designed and constructed an experimental NCM/PCM reactor out of 310 stainless steel in the form of a shell-and-tube heat exchanger, with the tube side packed with NCMP and the shell side filled with a eutectic mixture of NaCL, KCl, and MgCl{sub 2}. Our experimental results indicate that with proper attention to limiting thermal losses, our overall efficiency will exceed 90% (DOE goal: >75%) and our overall system cost will be only 33% (DOE goal: <50%) of the value of the delivered hydrogen. It appears that NCMP can be used to purify hydrogen streams and store hydrogen at the same time. These prospects make the NCMP/PCM reactor an attractive component in a reformer-based hydrogen fueling station.

  2. Post-occupancy energy efficiency evaluation of a LEED Platinum Federal Government facility

    NASA Astrophysics Data System (ADS)

    Tincher, Theresa

    The purpose of this study was to gain a comprehensive understanding of the Leadership in Energy and Environmental Design (LEEDRTM) certification system and its relevance to Federal policies, building codes, and building standards, develop experience with whole building energy modeling, and determine the actual post-occupancy energy usage as compared with developed model and design projections. This thesis hypothesized the U.S. Green Building Council's LEED rating system compared favorably to other policies, codes, and standards in use at the time, and the U.S. Bureau of Reclamations' LEED Platinum Lower Colorado Regional Office Green Building (LCROGB), located in Boulder City, Nevada, operated at least as energy efficiently as designed. Both hypotheses were shown to be true. Based on the design and development requirements for the 49,818 square foot LCROGB being studied, the primary building requirements addressed were the U.S. Guiding Principles for Federal Leadership in High Performance and Sustainable Buildings, ASHRAE Standard 90.1-2007, and the LEED V2009 certification system for new construction. LEED V2009 certification requirements compared favorably by either meeting or exceeding other stated requirements. The whole building energy simulation, QUick Energy Simulation Tool (eQUEST) Version 3.65, was used for the study, and baseline and proposed models were developed. The eQUEST results compared favorably with the designer's simulations developed using the Hourly Analysis Program (HAP) Version 4.5. eQUEST predicted a 32.7% savings in overall energy usage, compared to the HAP 38.9% prediction. In 2013, the LCROGB used 600,042 kWh of energy, and 60% was electrical and 40% was natural gas. This usage demonstrated high building efficiency with an Energy Use Intensity (EUI) of 41.1 kBtu/sf/yr. Following more than two years of post-occupancy operation, the LCROGB was electrically more efficient than predicted by either HAP or eQUEST, although the facility was

  3. High Efficiency, High Performance Clothes Dryer

    SciTech Connect

    Peter Pescatore; Phil Carbone

    2005-03-31

    This program covered the development of two separate products; an electric heat pump clothes dryer and a modulating gas dryer. These development efforts were independent of one another and are presented in this report in two separate volumes. Volume 1 details the Heat Pump Dryer Development while Volume 2 details the Modulating Gas Dryer Development. In both product development efforts, the intent was to develop high efficiency, high performance designs that would be attractive to US consumers. Working with Whirlpool Corporation as our commercial partner, TIAX applied this approach of satisfying consumer needs throughout the Product Development Process for both dryer designs. Heat pump clothes dryers have been in existence for years, especially in Europe, but have not been able to penetrate the market. This has been especially true in the US market where no volume production heat pump dryers are available. The issue has typically been around two key areas: cost and performance. Cost is a given in that a heat pump clothes dryer has numerous additional components associated with it. While heat pump dryers have been able to achieve significant energy savings compared to standard electric resistance dryers (over 50% in some cases), designs to date have been hampered by excessively long dry times, a major market driver in the US. The development work done on the heat pump dryer over the course of this program led to a demonstration dryer that delivered the following performance characteristics: (1) 40-50% energy savings on large loads with 35 F lower fabric temperatures and similar dry times; (2) 10-30 F reduction in fabric temperature for delicate loads with up to 50% energy savings and 30-40% time savings; (3) Improved fabric temperature uniformity; and (4) Robust performance across a range of vent restrictions. For the gas dryer development, the concept developed was one of modulating the gas flow to the dryer throughout the dry cycle. Through heat modulation in a

  4. Using business intelligence for efficient inter-facility patient transfer.

    PubMed

    Haque, Waqar; Derksen, Beth Ann; Calado, Devin; Foster, Lee

    2015-01-01

    In the context of inter-facility patient transfer, a transfer operator must be able to objectively identify a destination which meets the needs of a patient, while keeping in mind each facility's limitations. We propose a solution which uses Business Intelligence (BI) techniques to analyze data related to healthcare infrastructure and services, and provides a web based system to identify optimal destination(s). The proposed inter-facility transfer system uses a single data warehouse with an Online Analytical Processing (OLAP) cube built on top that supplies analytical data to multiple reports embedded in web pages. The data visualization tool includes map based navigation of the health authority as well as an interactive filtering mechanism which finds facilities meeting the selected criteria. The data visualization is backed by an intuitive data entry web form which safely constrains the data, ensuring consistency and a single version of truth. The overall time required to identify the destination for inter-facility transfers is reduced from hours to a few minutes with this interactive solution.

  5. Integrated Framework for Patient Safety and Energy Efficiency in Healthcare Facilities Retrofit Projects.

    PubMed

    Mohammadpour, Atefeh; Anumba, Chimay J; Messner, John I

    2016-07-01

    There is a growing focus on enhancing energy efficiency in healthcare facilities, many of which are decades old. Since replacement of all aging healthcare facilities is not economically feasible, the retrofitting of these facilities is an appropriate path, which also provides an opportunity to incorporate energy efficiency measures. In undertaking energy efficiency retrofits, it is vital that the safety of the patients in these facilities is maintained or enhanced. However, the interactions between patient safety and energy efficiency have not been adequately addressed to realize the full benefits of retrofitting healthcare facilities. To address this, an innovative integrated framework, the Patient Safety and Energy Efficiency (PATSiE) framework, was developed to simultaneously enhance patient safety and energy efficiency. The framework includes a step -: by -: step procedure for enhancing both patient safety and energy efficiency. It provides a structured overview of the different stages involved in retrofitting healthcare facilities and improves understanding of the intricacies associated with integrating patient safety improvements with energy efficiency enhancements. Evaluation of the PATSiE framework was conducted through focus groups with the key stakeholders in two case study healthcare facilities. The feedback from these stakeholders was generally positive, as they considered the framework useful and applicable to retrofit projects in the healthcare industry.

  6. Integrated Framework for Patient Safety and Energy Efficiency in Healthcare Facilities Retrofit Projects.

    PubMed

    Mohammadpour, Atefeh; Anumba, Chimay J; Messner, John I

    2016-07-01

    There is a growing focus on enhancing energy efficiency in healthcare facilities, many of which are decades old. Since replacement of all aging healthcare facilities is not economically feasible, the retrofitting of these facilities is an appropriate path, which also provides an opportunity to incorporate energy efficiency measures. In undertaking energy efficiency retrofits, it is vital that the safety of the patients in these facilities is maintained or enhanced. However, the interactions between patient safety and energy efficiency have not been adequately addressed to realize the full benefits of retrofitting healthcare facilities. To address this, an innovative integrated framework, the Patient Safety and Energy Efficiency (PATSiE) framework, was developed to simultaneously enhance patient safety and energy efficiency. The framework includes a step -: by -: step procedure for enhancing both patient safety and energy efficiency. It provides a structured overview of the different stages involved in retrofitting healthcare facilities and improves understanding of the intricacies associated with integrating patient safety improvements with energy efficiency enhancements. Evaluation of the PATSiE framework was conducted through focus groups with the key stakeholders in two case study healthcare facilities. The feedback from these stakeholders was generally positive, as they considered the framework useful and applicable to retrofit projects in the healthcare industry. PMID:27492415

  7. High efficiency thermionic converter studies

    NASA Technical Reports Server (NTRS)

    Huffman, F. N.; Sommer, A. H.; Balestra, C. L.; Briere, T. R.; Lieb, D.; Oettinger, P. E.; Goodale, D. B.

    1977-01-01

    Research in thermionic energy conversion technology is reported. The objectives were to produce converters suitable for use in out of core space reactors, radioisotope generators, and solar satellites. The development of emitter electrodes that operate at low cesium pressure, stable low work function collector electrodes, and more efficient means of space charge neutralization were investigated to improve thermionic converter performance. Potential improvements in collector properties were noted with evaporated thin film barium oxide coatings. Experiments with cesium carbonate suggest this substance may provide optimum combinations of cesium and oxygen for thermionic conversion.

  8. High energy efficient solid state laser sources

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1989-01-01

    Recent progress in the development of highly efficient coherent optical sources was reviewed. This work has focused on nonlinear frequency conversion of the highly coherent output of the non-planar ring laser oscillators developed earlier in the program, and includes high efficiency second harmonic generation and the operation of optical parametric oscillators for wavelength diversity and tunability.

  9. High energy efficient solid state laser sources

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1988-01-01

    Recent progress in the development of highly efficient coherent optical sources is reviewed. This work focusses on nonlinear frequency conversion of the highly coherent output of the Non-Planar Ring Laser Oscillators developed earlier in the program, and includes high efficiency second harmonic generation and the operation of optical parametric oscillators for wavelength diversity and tunability.

  10. Laboratory 15 kV high voltage solar array facility

    NASA Technical Reports Server (NTRS)

    Kolecki, J. C.; Gooder, S. T.

    1976-01-01

    The laboratory high voltage solar array facility is a photoelectric power generating system. Consisting of nine modules with over 23,000 solar cells, the facility is capable of delivering more than a kilowatt of power. The physical and electrical characteristics of the facility are described.

  11. Efficient high density train operations

    DOEpatents

    Gordon, Susanna P.; Evans, John A.

    2001-01-01

    The present invention provides methods for preventing low train voltages and managing interference, thereby improving the efficiency, reliability, and passenger comfort associated with commuter trains. An algorithm implementing neural network technology is used to predict low voltages before they occur. Once voltages are predicted, then multiple trains can be controlled to prevent low voltage events. Further, algorithms for managing inference are presented in the present invention. Different types of interference problems are addressed in the present invention such as "Interference. During Acceleration", "Interference Near Station Stops", and "Interference During Delay Recovery." Managing such interference avoids unnecessary brake/acceleration cycles during acceleration, immediately before station stops, and after substantial delays. Algorithms are demonstrated to avoid oscillatory brake/acceleration cycles due to interference and to smooth the trajectories of closely following trains. This is achieved by maintaining sufficient following distances to avoid unnecessary braking/accelerating. These methods generate smooth train trajectories, making for a more comfortable ride, and improve train motor reliability by avoiding unnecessary mode-changes between propulsion and braking. These algorithms can also have a favorable impact on traction power system requirements and energy consumption.

  12. Highly Efficient Multilayer Thermoelectric Devices

    NASA Technical Reports Server (NTRS)

    Boufelfel, Ali

    2006-01-01

    Multilayer thermoelectric devices now at the prototype stage of development exhibit a combination of desirable characteristics, including high figures of merit and high performance/cost ratios. These devices are capable of producing temperature differences of the order of 50 K in operation at or near room temperature. A solvent-free batch process for mass production of these state-of-the-art thermoelectric devices has also been developed. Like prior thermoelectric devices, the present ones have commercial potential mainly by virtue of their utility as means of controlled cooling (and/or, in some cases, heating) of sensors, integrated circuits, and temperature-critical components of scientific instruments. The advantages of thermoelectric devices for such uses include no need for circulating working fluids through or within the devices, generation of little if any noise, and high reliability. The disadvantages of prior thermoelectric devices include high power consumption and relatively low coefficients of performance. The present development program was undertaken in the hope of reducing the magnitudes of the aforementioned disadvantages and, especially, obtaining higher figures of merit for operation at and near room temperature. Accomplishments of the program thus far include development of an algorithm to estimate the heat extracted by, and the maximum temperature drop produced by, a thermoelectric device; solution of the problem of exchange of heat between a thermoelectric cooler and a water-cooled copper block; retrofitting of a vacuum chamber for depositing materials by sputtering; design of masks; and fabrication of multilayer thermoelectric devices of two different designs, denoted I and II. For both the I and II designs, the thicknesses of layers are of the order of nanometers. In devices of design I, nonconsecutive semiconductor layers are electrically connected in series. Devices of design II contain superlattices comprising alternating electron

  13. High efficiency solar photovoltaic power module concept

    NASA Technical Reports Server (NTRS)

    Bekey, I.

    1978-01-01

    The investigation of a preliminary concept for high efficiency solar power generation in space is presented. The concept was a synergistic combination of spectral splitting, tailored bandgap cells, high concentration ratios, and cool cell areas.

  14. High-Efficiency dc/dc Converter

    NASA Technical Reports Server (NTRS)

    Sturman, J.

    1982-01-01

    High-efficiency dc/dc converter has been developed that provides commonly used voltages of plus or minus 12 Volts from an unregulated dc source of from 14 to 40 Volts. Unique features of converter are its high efficiency at low power level and ability to provide output either larger or smaller than input voltage.

  15. High-Efficiency Power Module

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N. (Inventor); Wintucky, Edwin G. (Inventor)

    2015-01-01

    One or more embodiments of the present invention pertain to an all solid-state microwave power module. The module includes a plurality of solid-state amplifiers configured to amplify a signal using a low power stage, a medium power stage, and a high power stage. The module also includes a power conditioner configured to activate a voltage sequencer (e.g., bias controller) when power is received from a power source. The voltage sequencer is configured to sequentially apply voltage to a gate of each amplifier and sequentially apply voltage to a drain of each amplifier.

  16. High-Efficiency Power Module

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N (Inventor); Wintucky, Edwin G (Inventor)

    2013-01-01

    One or more embodiments of the present invention pertain to an all solid-state microwave power module. The module includes a plurality of solid-state amplifiers configured to amplify a signal using a low power stage, a medium power stage, and a high power stage. The module also includes a power conditioner configured to activate a voltage sequencer (e.g., bias controller) when power is received from a power source. The voltage sequencer is configured to sequentially apply voltage to a gate of each amplifier and sequentially apply voltage to a drain of each amplifier.

  17. High-efficiency target-ion sources for RIB generation

    SciTech Connect

    Alton, G.D.

    1993-12-31

    A brief review is given of high-efficiency ion sources which have been developed or are under development at ISOL facilities which show particular promise for use at existing, future, or radioactive ion beam (RIB) facilities now under construction. Emphasis will be placed on those sources which have demonstrated high ionization efficiency, species versatility, and operational reliability and which have been carefully designed for safe handling in the high level radioactivity radiation fields incumbent at such facilities. Brief discussions will also be made of the fundamental processes which affect the realizable beam intensities in target-ion sources. Among the sources which will be reviewed will be selected examples of state-of-the-art electron-beam plasma-type ion sources, thermal-ionization, surface-ionization, ECR, and selectively chosen ion source concepts which show promise for radioactive ion beam generation. A few advanced, chemically selective target-ion sources will be described, such as sources based on the use of laser-resonance ionization, which, in principle, offer a more satisfactory solution to isobaric contamination problems than conventional electromagnetic techniques. Particular attention will be given to the sources which have been selected for initial or future use at the Holifield Radioactive Ion Beam Facility now under construction at the Oak Ridge National Laboratory.

  18. Facile removal of high mannose structures prior to extracting complex type N-glycans from de-N-glycosylated peptides retained by C18 solid phase to allow more efficient glycomic mapping

    PubMed Central

    Lin, Chi-Hung; Kuo, Chu-Wei; Jarvis, Donald L; Khoo, Kay-Hooi

    2014-01-01

    The relative amount of high mannose structures within an N-glycomic pool differs from one source to another but quite often it predominates over the larger size complex type structures carrying biologically important glyco-epitopes. An efficient method to separate these two classes of N-glycans would significantly aid in detecting the lower abundant components by mass spectrometry. Capitalizing on an initial observation that only high mannose type structures were recovered in the flow through fraction when PNGase F digested peptides were passed through a C18 cartridge in 0.1% formic acid, we demonstrated here that native complex type N-glycans can be retained by C18 cartridge and to be efficiently separated from both the smaller high mannose type structures, as well as de-N-glycosylated peptides by stepwise elution with increasing acetonitrile concentration. The weak retention of the largely hydrophilic N-glycans on C18 resin is dependent not only on size but also increased by the presence of α6-fucosylation. This was shown by comparing the resulting N-glycomic profiles of the washed and low acetonitrile eluted fractions derived from both a human cancer cell line and an insect cell line. PMID:24174266

  19. High Efficiency Microwave Power Amplifier (HEMPA) Design

    NASA Technical Reports Server (NTRS)

    Sims, W. Herbert

    2004-01-01

    This paper will focus on developing an exotic switching technique that enhances the DC-to-RF conversion efficiency of microwave power amplifiers. For years, switching techniques implemented in the 10 kHz to 30 MHz region have resulted in DC-to-RF conversion efficiencies of 90-95-percent. Currently amplifier conversion efficiency, in the 2-3 GHz region approaches, 10-20-percent. Using a combination of analytical modeling and hardware testing, a High Efficiency Microwave Power Amplifier was built that demonstrated conversion efficiencies four to five times higher than current state of the art.

  20. Facile synthesis of efficient visible active C-doped TiO{sub 2} nanomaterials with high surface area for the simultaneous removal of phenol and Cr(VI)

    SciTech Connect

    Mani, A.Daya; Reddy, P.Manoj Kumar; Srinivaas, M.; Ghosal, P.; Xanthopoulos, N.; Subrahmanyam, Ch.

    2015-01-15

    Highlights: • Facile synthesis of C-doped TiO{sub 2} nanomaterials with high surface area. • Utilization of citric acid and ascorbic acid as fuels based on evolution of gases. • Enhanced visible activity for the oxidation of phenol and reduction of Cr(VI). • Study of simultaneous oxidation of phenol and reduction of Cr(VI) for the first time. • Proposed plausible mechanism for the simultaneous removal of phenol and Cr(VI). - Abstract: A single step synthesis of carbon doped TiO{sub 2} (anatase) nanomaterials have been reported by using combustion synthesis using ascorbic acid and citric acid fuels. X-ray diffraction studies indicated the formation of nanosized anatase titania, whereas, transmission electron microscopy confirmed the formation of nanosized TiO{sub 2} anatase. The carbon doping into TiO{sub 2} matrix was identified by X-ray photoelectron spectroscopy, whereas, thermogravimetric study quantified the carbon doping. Diffuse reflectance UV–vis spectra indicated the band gap of less than 3 eV, a prerequisite for the photocatalytic activity under visible light irradiation. The N{sub 2} adsorption studies revealed the high surface area (upto 290 m{sup 2}/g) of the synthesized photocatalysts. Typical photocatalytic activity data indicated that the simultaneous removal of Cr(VI) and phenol is advantageous than degradation of the individual pollutants.

  1. Multicolor, High Efficiency, Nanotextured LEDs

    SciTech Connect

    Jung Han; Arto Nurmikko

    2011-09-30

    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.

  2. A facile and high-yield formation of dipyrrin-boronic acid dyads and triads: a light-harvesting system in the visible region based on the efficient energy transfer.

    PubMed

    Yamamura, Masaki; Yazaki, Shinya; Seki, Motofumi; Matsui, Yasunori; Ikeda, Hiroshi; Nabeshima, Tatsuya

    2015-03-01

    Artificial light-harvesting systems, Ar,O-BODIPY dyads and triads conjugated with a light harvester, were synthesized in high yield by the reaction of an N2O2-type dipyrrin with boronic acids. Dyad 2 having a pyrene unit underwent quantitative Förster resonance energy transfer (FRET) from the antenna unit, pyrene, to the fluorophore unit, Ar,O-BODIPY. Triads 3·5 and 4·5 were quantitatively prepared by mixing pyridine-appended compounds 3 and 4 with saloph·Zn complex 5, respectively. Triad 4·5 underwent efficient FRET from the saloph·Zn complex unit to the fluorophore unit at the rate of 2.0 × 10(11) s(-1). Interestingly, the fluorescence quenching process in the excited state of the triad 3·5 took place following the energy transfer event. Thus, appropriate positioning of the energy donor and acceptor is necessary to construct a highly efficient FRET system. PMID:25554254

  3. High School Educational Specifications: Facilities Planning Standards. Edition I.

    ERIC Educational Resources Information Center

    Jefferson County School District R-1, Denver, CO.

    The Jefferson County School District (Colorado) has developed a manual of high school specifications for Design Advisory Groups and consultants to use for planning and designing the district's high school facilities. The specifications are provided to help build facilities that best meet the educational needs of the students to be served.…

  4. High Efficiency Centrifugal Compressor for Rotorcraft Applications

    NASA Technical Reports Server (NTRS)

    Medic, Gorazd; Sharma, Om P.; Jongwook, Joo; Hardin, Larry W.; McCormick, Duane C.; Cousins, William T.; Lurie, Elizabeth A.; Shabbir, Aamir; Holley, Brian M.; Van Slooten, Paul R.

    2014-01-01

    The report "High Efficiency Centrifugal Compressor for Rotorcraft Applications" documents the work conducted at UTRC under the NRA Contract NNC08CB03C, with cost share 2/3 NASA, and 1/3 UTRC, that has been extended to 4.5 years. The purpose of this effort was to identify key technical barriers to advancing the state-of-the-art of small centrifugal compressor stages; to delineate the measurements required to provide insight into the flow physics of the technical barriers; to design, fabricate, install, and test a state-of-the-art research compressor that is representative of the rear stage of an axial-centrifugal aero-engine; and to acquire detailed aerodynamic performance and research quality data to clarify flow physics and to establish detailed data sets for future application. The design activity centered on meeting the goal set outlined in the NASA solicitation-the design target was to increase efficiency at higher work factor, while also reducing the maximum diameter of the stage. To fit within the existing Small Engine Components Test Facility at NASA Glenn Research Center (GRC) and to facilitate component re-use, certain key design parameters were fixed by UTRC, including impeller tip diameter, impeller rotational speed, and impeller inlet hub and shroud radii. This report describes the design effort of the High Efficiency Centrifugal Compressor stage (HECC) and delineation of measurements, fabrication of the compressor, and the initial tests that were performed. A new High-Efficiency Centrifugal Compressor stage with a very challenging reduction in radius ratio was successfully designed, fabricated and installed at GRC. The testing was successful, with no mechanical problems and the running clearances were achieved without impeller rubs. Overall, measured pressure ratio of 4.68, work factor of 0.81, and at design exit corrected flow rate of 3 lbm/s met the target requirements. Polytropic efficiency of 85.5 percent and stall margin of 7.5 percent were

  5. High efficiency fuel cell/advanced turbine power cycles

    SciTech Connect

    Morehead, H.

    1995-10-19

    An outline of the Westinghouse high-efficiency fuel cell/advanced turbine power cycle is presented. The following topics are discussed: The Westinghouse SOFC pilot manufacturing facility, cell scale-up plan, pressure effects on SOFC power and efficiency, sureCell versus conventional gas turbine plants, sureCell product line for distributed power applications, 20 MW pressurized-SOFC/gas turbine power plant, 10 MW SOFC/CT power plant, sureCell plant concept design requirements, and Westinghouse SOFC market entry.

  6. Energy-Efficiency & Water Institute Research Facility, Purdue University, (IN)

    SciTech Connect

    Nnanna, Agbai

    2015-01-30

    The renovation of the Schneider Avenue Building to construct two research laboratories within the building is complete. The research laboratories are for the Purdue Calumet Water Institute and the Energy Efficiency and Reliability Center. The Water Institute occupies approximately 1000+ SF of research space plus supporting offices. The Energy-Efficiency Center occupies approximately 1000+ SF that houses the research space. The labs will enhance the Water & Energy Institute’s research capabilities necessary to tackle these issues through the development of practical approaches critical to local government and industry. The addition of these research laboratories to the Purdue University Calumet campus is in both direct support of the University’s Strategic Plan as well as the 2008 Campus Master Plan that identifies a 20% shortage of research space.

  7. Money for Research, Not for Energy Bills: Finding Energy and Cost Savings in High Performance Computer Facility Designs

    SciTech Connect

    Drewmark Communications; Sartor, Dale; Wilson, Mark

    2010-07-01

    High-performance computing facilities in the United States consume an enormous amount of electricity, cutting into research budgets and challenging public- and private-sector efforts to reduce energy consumption and meet environmental goals. However, these facilities can greatly reduce their energy demand through energy-efficient design of the facility itself. Using a case study of a facility under design, this article discusses strategies and technologies that can be used to help achieve energy reductions.

  8. Strategic interaction among hospitals and nursing facilities: the efficiency effects of payment systems and vertical integration.

    PubMed

    Banks, D; Parker, E; Wendel, J

    2001-03-01

    Rising post-acute care expenditures for Medicare transfer patients and increasing vertical integration between hospitals and nursing facilities raise questions about the links between payment system structure, the incentive for vertical integration and the impact on efficiency. In the United States, policy-makers are responding to these concerns by initiating prospective payments to nursing facilities, and are exploring the bundling of payments to hospitals. This paper develops a static profit-maximization model of the strategic interaction between the transferring hospital and a receiving nursing facility. This model suggests that the post-1984 system of prospective payment for hospital care, coupled with nursing facility payments that reimburse for services performed, induces inefficient under-provision of hospital services and encourages vertical integration. It further indicates that the extension of prospective payment to nursing facilities will not eliminate the incentive to vertically integrate, and will not result in efficient production unless such integration takes place. Bundling prospective payments for hospitals and nursing facilities will neither remove the incentive for vertical integration nor induce production efficiency without such vertical integration. However, bundled payment will induce efficient production, with or without vertical integration, if nursing facilities are reimbursed for services performed.

  9. Very High Efficiency Solar Cell Modules

    SciTech Connect

    Barnett, A.; Kirkpatrick, D.; Honsberg, C.; Moore, D.; Wanlass, M.; Emery, K.; Schwartz, R.; Carlson, D.; Bowden, S.; Aiken, D.; Gray, A.; Kurtz, S.; Kazmerski, L., et al

    2009-01-01

    The Very High Efficiency Solar Cell (VHESC) program is developing integrated optical system - PV modules for portable applications that operate at greater than 50% efficiency. We are integrating the optical design with the solar cell design, and have entered previously unoccupied design space. Our approach is driven by proven quantitative models for the solar cell design, the optical design, and the integration of these designs. Optical systems efficiency with an optical efficiency of 93% and solar cell device results under ideal dichroic splitting optics summing to 42.7 {+-} 2.5% are described.

  10. Multi Band Gap High Efficiency Converter (RAINBOW)

    NASA Technical Reports Server (NTRS)

    Bekey, I.; Lewis, C.; Phillips, W.; Shields, V.; Stella, P.

    1997-01-01

    The RAINBOW multi band gap system represents a unique combination of solar cells, concentrators and beam splitters. RAINBOW is a flexible system which can readily expand as new high efficiency components are developed.

  11. High-efficiency silicon solar cell research

    NASA Technical Reports Server (NTRS)

    Daud, T.

    1984-01-01

    Progress reports on research in high-efficiency silicon solar cells were presented by eight contractors and JPL. The presentations covered the issues of Bulk and Surface Loss, Modeling, Measurements, and Proof of Concept.

  12. Design issues for a laboratory high gain fusion facility

    SciTech Connect

    Hogan, W.J.

    1987-11-02

    In an inertial fusion laboratory high gain facility, experiments will be carried out with up to 1000 MJ of thermonuclear yield. The experiment area of such a facility will include many systems and structures that will have to operate successfully in the difficult environment created by the sudden large energy release. This paper estimates many of the nuclear effects that will occur, discusses the implied design issues and suggests possible solutions so that a useful experimental facility can be built. 4 figs.

  13. Energy Efficient Florida Educational Facilities: Phase VI. Progress Report: Phase I and II.

    ERIC Educational Resources Information Center

    Callahan, Michael P.; Parker, Danny S.

    A Florida study examined differences in energy uses in two adjacent portable classrooms to determine if these types of facilities can be made more energy efficient through retrofitting. Retrofitting included an efficient lighting system, new air conditioners, and reflective white metal roofs. Data show the white metal roofing reduced roof,…

  14. Research Support Facility - A Model of Super Efficiency (RSF) (Fact Sheet)

    SciTech Connect

    Not Available

    2010-08-01

    This fact sheet published by the National Renewable Energy Laboratory discusses the lab's newest building, the Research Support Facility (RSF). The RSF is a showcase for ultra-efficient workplaces. Various renewable energy and energy efficiency features have been employed so that the building achieves a Leadership in Energy and Environmental Design (LEED) Platinum rating from the U.S. Green Building Council.

  15. Occupational Safety Review of High Technology Facilities

    SciTech Connect

    Lee Cadwallader

    2005-01-31

    This report contains reviews of operating experiences, selected accident events, and industrial safety performance indicators that document the performance of the major US DOE magnetic fusion experiments and particle accelerators. These data are useful to form a basis for the occupational safety level at matured research facilities with known sets of safety rules and regulations. Some of the issues discussed are radiation safety, electromagnetic energy exposure events, and some of the more widespread issues of working at height, equipment fires, confined space work, electrical work, and other industrial hazards. Nuclear power plant industrial safety data are also included for comparison.

  16. Modular High Current Test Facility at LLNL

    SciTech Connect

    Tully, L K; Goerz, D A; Speer, R D; Ferriera, T J

    2008-05-20

    This paper describes the 1 MA, 225 kJ test facility in operation at Lawrence Livermore National Laboratory (LLNL). The capacitor bank is constructed from three parallel 1.5 mF modules. The modules are capable of switching simultaneously or sequentially via solid dielectric puncture switches. The bank nominally operates up to 10 kV and reaches peak current with all three cabled modules in approximately 30 {micro}s. Parallel output plates from the bank allow for cable or busbar interfacing to the load. This versatile bank is currently in use for code validation experiments, railgun related activities, switch testing, and diagnostic development.

  17. Managing the Theatre Facility at Smoky Hill High School.

    ERIC Educational Resources Information Center

    Pearl, Michael

    1989-01-01

    Discusses the management of a school theater facility. Discusses the role of the theater manager at Smoky Hill High School. Discusses the creation of the plan to oversee the operation and scheduling of the theater facility. Includes a copy of the contract form for using the theater. (SR)

  18. High efficiency advanced absorption heat pump

    NASA Astrophysics Data System (ADS)

    Reid, E. A., Jr.

    1982-03-01

    A high efficiency absorption heat pump for the residential market is investigated. The performance targets established for this high efficiency absorption heat pump are a heating coefficient of performance of 1.5 and a cooling coefficient of performance of 0.8 at rating conditions, including parasitic electric power consumption. The resulting heat pump would have a space heating capacity of 68,000 BTU/hour, and a space cooling capacity of 36,000 BTU/hour at rating conditions. A very simplified schematic block diagram of the high efficiency absorption heat pump cycle is shown. High temperature, high pressure, refrigerant vapor is produced in the refrigerant generator and heat exchange system, is condensed to a liquid in the condenser, expanded to a low pressure vapor in the evaporator, and mixed with and reabsorbed into the weakened solution returned from the refrigerant generator and heat exchange system in the absorber.

  19. Green Schools as High Performance Learning Facilities

    ERIC Educational Resources Information Center

    Gordon, Douglas E.

    2010-01-01

    In practice, a green school is the physical result of a consensus process of planning, design, and construction that takes into account a building's performance over its entire 50- to 60-year life cycle. The main focus of the process is to reinforce optimal learning, a goal very much in keeping with the parallel goals of resource efficiency and…

  20. Facile Fabrication of Sandwich Structured WO3 Nanoplate Arrays for Efficient Photoelectrochemical Water Splitting.

    PubMed

    Feng, Xiaoyang; Chen, Yubin; Qin, Zhixiao; Wang, Menglong; Guo, Liejin

    2016-07-20

    Herein, sandwich structured tungsten trioxide (WO3) nanoplate arrays were first synthesized for photoelectrochemical (PEC) water splitting via a facile hydrothermal method followed by an annealing treatment. It was demonstrated that the annealing temperature played an important role in determining the morphology and crystal phase of the WO3 film. Only when the hydrothermally prepared precursor was annealed at 500 °C could the sandwich structured WO3 nanoplates be achieved, probably due to the crystalline phase transition and increased thermal stress during the annealing process. The sandwich structured WO3 photoanode exhibited a photocurrent density of 1.88 mA cm(-2) and an incident photon-to-current conversion efficiency (IPCE) as high as 65% at 400 nm in neutral Na2SO4 solution under AM 1.5G illumination. To our knowledge, this value is one of the best PEC performances for WO3 photoanodes. Meanwhile, simultaneous hydrogen and oxygen evolution was demonstrated for the PEC water splitting. It was concluded that the high PEC performance should be attributed to the large electrochemically active surface area and active monoclinic phase. The present study can provide guidance to develop highly efficient nanostructured photoelectrodes with the favorable morphology.

  1. High efficiency pump for space helium transfer

    NASA Technical Reports Server (NTRS)

    Hasenbein, Robert; Izenson, Michael G.; Swift, Walter L.; Sixsmith, Herbert

    1991-01-01

    A centrifugal pump was developed for the efficient and reliable transfer of liquid helium in space. The pump can be used to refill cryostats on orbiting satellites which use liquid helium for refrigeration at extremely low temperatures. The pump meets the head and flow requirements of on-orbit helium transfer: a flow rate of 800 L/hr at a head of 128 J/kg. The overall pump efficiency at the design point is 0.45. The design head and flow requirements are met with zero net positive suction head, which is the condition in an orbiting helium supply Dewar. The mass transfer efficiency calculated for a space transfer operation is 0.99. Steel ball bearings are used with gas fiber-reinforced teflon retainers to provide solid lubrication. These bearings have demonstrated the longest life in liquid helium endurance tests under simulated pumping conditions. Technology developed in the project also has application for liquid helium circulation in terrestrial facilities and for transfer of cryogenic rocket propellants in space.

  2. High-speed seal and bearing test facility

    NASA Technical Reports Server (NTRS)

    Panos, Jean B.

    1994-01-01

    The following topics are discussed in this viewgraph presentation: high speed seal/bearing rig background, project status, facility features, test rig capabilities, EMD testing advantages, and future opportunities.

  3. The Jefferson Lab High Power THz User Facility

    SciTech Connect

    John Klopf; Amelia Greer; Joseph Gubeli; George Neil; Michelle D. Shinn; Timothy Siggins; David W. Waldman; Gwyn Williams; Alan Todd; Vincent Christina; Oleg Chubar

    2007-04-27

    We describe here, a high power (100 Watt average, 10 MW peak) broadband THz facility based on emission from sub-picosecond bunches of relativistic electrons and the beam transport system that delivers this beam in to a user laboratory.

  4. Technology Development for High Efficiency Optical Communications

    NASA Technical Reports Server (NTRS)

    Farr, William H.

    2012-01-01

    Deep space optical communications is a significantly more challenging operational domain than near Earth space optical communications, primarily due to effects resulting from the vastly increased range between transmitter and receiver. The NASA Game Changing Development Program Deep Space Optical Communications Project is developing four key technologies for the implementation of a high efficiency telecommunications system that will enable greater than 10X the data rate of a state-of-the-art deep space RF system (Ka-band) for similar transceiver mass and power burden on the spacecraft. These technologies are a low mass spacecraft disturbance isolation assembly, a flight qualified photon counting detector array, a high efficiency flight laser amplifier and a high efficiency photon counting detector array for the ground-based receiver.

  5. High-efficiency solid state power amplifier

    NASA Technical Reports Server (NTRS)

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

    2005-01-01

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

  6. High efficiency particulate removal with sintered metal filters

    NASA Astrophysics Data System (ADS)

    Kirstein, B. E.; Paplawsky, W. J.; Pence, D. T.; Hedahl, T. G.

    Because of their particle removal efficiencies and durability, sintered metal filters have been chosen for high efficiency particulate air (HEPA) filter protection in the off gas treatment system for a proposed transuranic waste treatment facility. Process evaluation of sintered metal filters indicated a lack of sufficient process design data to ensure trouble free operation. Subsequence pilot scale testing was performed with flyash as the test particulate. The test results showed that the sintered metal filters can have an efficiency greater than 0.9999999 for the specific test conditions used. Stable pressure drop characteristics were observed in pulsed and reversed flow blowback modes of operation. Over 4900 hours of operation were obtained with operating conditions ranging up to approximately 90 C and 24 vol % water vapor in the gas stream.

  7. Facile integration of multiple magnetite nanoparticles for theranostics combining efficient MRI and thermal therapy

    NASA Astrophysics Data System (ADS)

    Huang, Guoming; Zhu, Xianglong; Li, Hui; Wang, Lirong; Chi, Xiaoqin; Chen, Jiahe; Wang, Xiaomin; Chen, Zhong; Gao, Jinhao

    2015-01-01

    Multifunctional nanostructures with both diagnostic and therapeutic capabilities have attracted considerable attention in biomedical research because they can offer great advantages in disease management and prognosis. In this work, a facile way to transfer the hydrophobic iron oxide (IO) nanoparticles into aqueous media by employing carboxylic graphene oxide (GO-COOH) as the transferring agent has been reported. In this one-step process, IO nanoparticles adhere to GO-COOH and form water-dispersible clusters via hydrophobic interactions between the hydrophobic ligands of IO nanoparticles and the basal plane of GO-COOH. The multiple IO nanoparticles on GO-COOH sheets (IO/GO-COOH) present a significant increase in T2 contrast enhancement. Moreover, the IO/GO-COOH nanoclusters also display a high photothermal conversion efficiency and can effectively inhibit tumor growth through the photothermal effects. It is envisioned that such IO/GO-COOH nanocomposites combining efficient MRI and photothermal therapy hold great promise in theranostic applications.Multifunctional nanostructures with both diagnostic and therapeutic capabilities have attracted considerable attention in biomedical research because they can offer great advantages in disease management and prognosis. In this work, a facile way to transfer the hydrophobic iron oxide (IO) nanoparticles into aqueous media by employing carboxylic graphene oxide (GO-COOH) as the transferring agent has been reported. In this one-step process, IO nanoparticles adhere to GO-COOH and form water-dispersible clusters via hydrophobic interactions between the hydrophobic ligands of IO nanoparticles and the basal plane of GO-COOH. The multiple IO nanoparticles on GO-COOH sheets (IO/GO-COOH) present a significant increase in T2 contrast enhancement. Moreover, the IO/GO-COOH nanoclusters also display a high photothermal conversion efficiency and can effectively inhibit tumor growth through the photothermal effects. It is envisioned

  8. Facile synthesis of efficient photocatalytic tantalum nitride nanoparticles

    SciTech Connect

    Wang, Zheng; Wang, Jiangting; Hou, Jungang; Huang, Kai; Jiao, Shuqiang; Zhu, Hongmin

    2012-11-15

    Graphical abstract: Tantalum nitride nanoparticles as a visible-light-driven photocatalyst prepared by a novel homogeneously chemical reduction of tantalum pentachloride using sodium in liquid ammonia and the morphologies, visible-light photocatalytic properties and stability of tantalum nitride nanoparticles were investigated. Highlights: ► Tantalum nitride nanoparticles have been prepared by a homogeneously chemical reduction. ► The crystal structure of tantalum nitride was determined by Rietveld refinement and XRD patterns. ► The Tantalum nitride nanoparticle size was in the range of 20–50 nm. ► Much high photocatalytic activities of Ta{sub 3}N{sub 5} nanoparticles were obtained under visible-light irradiation. -- Abstract: Tantalum nitride nanoparticles, as visible-light photocatalysts were synthesized by a two-step homogeneously chemical reduction without any polymers and templates. The well-crystallized Ta{sub 3}N{sub 5} nanoparticles with a range of 20–50 nm in size have been characterized by a number of techniques, such as XRD, XPS, SEM, TEM, BET and UV–Vis spectrum. Most importantly, the Ta{sub 3}N{sub 5} nanoparticles with good stability exhibited higher photooxidation activities in the water splitting and degradation of methylene blue under visible light irradiation than bulk Ta{sub 3}N{sub 5} particles and commercial P25 TiO{sub 2}, demonstrating that Ta{sub 3}N{sub 5} nanoparticle is a promising candidate as a visible-light photocatalyst.

  9. Proposal for superstructure based high efficiency photovoltaics

    NASA Technical Reports Server (NTRS)

    Wagner, M.; Leburton, J. P.

    1986-01-01

    A novel class of cascade structures is proposed which features multijunction upper subcells, referred to as superstructure high-efficiency photovoltaics (SHEPs). The additional junctions enhance spectral response and improve radiation tolerance by reducing bulk recombination losses. This is important because ternary III-V alloys, which tend to have short minority-carrier diffusion lengths, are the only viable materials for the high-bandgap upper subcells required for cascade solar cells. Realistic simulations of AlGaAs SHEPs show that one-sun AM0 efficiencies in excess of 26 percent are possible.

  10. High-efficiency filtration meets IAQ goals

    SciTech Connect

    Aaronson, E.L. ); Fencl, F. )

    1994-12-01

    This article describes multi-stage filtration system which provided initial cost savings and is expected to save even more in energy costs while fulfilling IAQ requirements. The use of high-efficiency filtration has enabled the city of Kansas City, Mo., to save an estimated $500,000 in initial HVAC system costs for its Bartle Hall expansion project, which is currently under construction. Once operational, the new HVAC system, with its high-efficiency filters, is expected to save thousands of dollars per week more in energy costs while also delivering superior indoor air quality (IAQ).

  11. Measure Guideline. High Efficiency Natural Gas Furnaces

    SciTech Connect

    Brand, L.; Rose, W.

    2012-10-01

    This measure guideline covers installation of high-efficiency gas furnaces, including: when to install a high-efficiency gas furnace as a retrofit measure; how to identify and address risks; and the steps to be used in the selection and installation process. The guideline is written for Building America practitioners and HVAC contractors and installers. It includes a compilation of information provided by manufacturers, researchers, and the Department of Energy as well as recent research results from the Partnership for Advanced Residential Retrofit (PARR) Building America team.

  12. Measure Guideline: High Efficiency Natural Gas Furnaces

    SciTech Connect

    Brand, L.; Rose, W.

    2012-10-01

    This Measure Guideline covers installation of high-efficiency gas furnaces. Topics covered include when to install a high-efficiency gas furnace as a retrofit measure, how to identify and address risks, and the steps to be used in the selection and installation process. The guideline is written for Building America practitioners and HVAC contractors and installers. It includes a compilation of information provided by manufacturers, researchers, and the Department of Energy as well as recent research results from the Partnership for Advanced Residential Retrofit (PARR) Building America team.

  13. Highly efficient heralding of entangled single photons.

    PubMed

    Ramelow, Sven; Mech, Alexandra; Giustina, Marissa; Gröblacher, Simon; Wieczorek, Witlef; Beyer, Jörn; Lita, Adriana; Calkins, Brice; Gerrits, Thomas; Nam, Sae Woo; Zeilinger, Anton; Ursin, Rupert

    2013-03-25

    Single photons are an important prerequisite for a broad spectrum of quantum optical applications. We experimentally demonstrate a heralded single-photon source based on spontaneous parametric down-conversion in collinear bulk optics, and fiber-coupled bolometric transition-edge sensors. Without correcting for background, losses, or detection inefficiencies, we measure an overall heralding efficiency of 83%. By violating a Bell inequality, we confirm the single-photon character and high-quality entanglement of our heralded single photons which, in combination with the high heralding efficiency, are a necessary ingredient for advanced quantum communication protocols such as one-sided device-independent quantum key distribution.

  14. Facility Configuration Study of the High Temperature Gas-Cooled Reactor Component Test Facility

    SciTech Connect

    S. L. Austad; L. E. Guillen; D. S. Ferguson; B. L. Blakely; D. M. Pace; D. Lopez; J. D. Zolynski; B. L. Cowley; V. J. Balls; E.A. Harvego, P.E.; C.W. McKnight, P.E.; R.S. Stewart; B.D. Christensen

    2008-04-01

    A test facility, referred to as the High Temperature Gas-Cooled Reactor Component Test Facility or CTF, will be sited at Idaho National Laboratory for the purposes of supporting development of high temperature gas thermal-hydraulic technologies (helium, helium-Nitrogen, CO2, etc.) as applied in heat transport and heat transfer applications in High Temperature Gas-Cooled Reactors. Such applications include, but are not limited to: primary coolant; secondary coolant; intermediate, secondary, and tertiary heat transfer; and demonstration of processes requiring high temperatures such as hydrogen production. The facility will initially support completion of the Next Generation Nuclear Plant. It will secondarily be open for use by the full range of suppliers, end-users, facilitators, government laboratories, and others in the domestic and international community supporting the development and application of High Temperature Gas-Cooled Reactor technology. This pre-conceptual facility configuration study, which forms the basis for a cost estimate to support CTF scoping and planning, accomplishes the following objectives: • Identifies pre-conceptual design requirements • Develops test loop equipment schematics and layout • Identifies space allocations for each of the facility functions, as required • Develops a pre-conceptual site layout including transportation, parking and support structures, and railway systems • Identifies pre-conceptual utility and support system needs • Establishes pre-conceptual electrical one-line drawings and schedule for development of power needs.

  15. Biosecurity Measures in 48 Isolation Facilities Managing Highly Infectious Diseases

    PubMed Central

    Puro, Vincenzo; Schilling, Stefan; Thomson, Gail; De Iaco, Giuseppina; Brouqui, Philippe; Maltezou, Helena C.; Bannister, Barbara; Gottschalk, René; Brodt, Hans-Rheinhard; Ippolito, Giuseppe

    2012-01-01

    Biosecurity measures are traditionally applied to laboratories, but they may also be usefully applied in highly specialized clinical settings, such as the isolation facilities for the management of patients with highly infectious diseases (eg, viral hemorrhagic fevers, SARS, smallpox, potentially severe pandemic flu, and MDR- and XDR-tuberculosis). In 2009 the European Network for Highly Infectious Diseases conducted a survey in 48 isolation facilities in 16 European countries to determine biosecurity measures for access control to the facility. Security personnel are present in 39 facilities (81%). In 35 facilities (73%), entrance to the isolation area is restricted; control methods include electronic keys, a PIN system, closed-circuit TV, and guards at the doors. In 25 facilities (52%), identification and registration of all staff entering and exiting the isolation area are required. Access control is used in most surveyed centers, but specific lacks exist in some facilities. Further data are needed to assess other biosecurity aspects, such as the security measures during the transportation of potentially contaminated materials and measures to address the risk of an “insider attack.” PMID:22571373

  16. Evaluation of a high-efficiency, filter-bank system.

    PubMed

    Martin, Stephen B; Beamer, Bryan R; Moyer, Ernest S

    2006-04-01

    National Institute for Occupational Safety and Health (NIOSH) investigators evaluated filtration efficiencies at three U.S. Postal Service (USPS) facilities. Ventilation and filtration systems (VFSs) had been installed after the 2001 bioterrorist attacks when the USPS unknowingly processed letters laden with B. anthracis spores. The new VFS units included high-efficiency particulate air (HEPA) filters and were required by USPS contract specifications to provide an overall filtration efficiency of at least 99.97% for particles between 0.3 microm and 3.0 micro m. The USPS evaluation involved a modification of methodology used to test total filtration system efficiency in agricultural tractor cab enclosures. The modified sampling strategy not only proved effective for monitoring the total filtration system component of VFS performance but also distinguished between filtration systems performing to the high USPS performance criteria and those needing repair or replacement. The results clearly showed the importance of choosing a pair of optical particle counters that have been closely matched immediately prior to testing. The modified methodology is readily adaptable to any workplace wishing to evaluate air filtration systems, including high-efficiency systems. PMID:16531293

  17. High efficiency novel window air conditioner

    SciTech Connect

    Bansal, Pradeep

    2015-01-01

    This paper presents the technical development of a high efficiency window air conditioner. In order to achieve higher energy efficiency ratio (EER), the original capacity of the R410A unit was downgraded by replacing the original compressor with a lower capacity but higher EER compressor, while all heat exchangers and the chassis from the original unit were retained. The other subsequent major modifications included – the AC fan motor being replaced with a brushless high efficiency electronically commuted motor (ECM) motor, the capillary tube being replaced with a needle valve to better control the refrigerant flow and refrigerant set points, and R410A being replaced with drop-in environmentally friendly binary mixture of R32 (85% molar concentration)/R125 (15% molar concentration). All these modifications resulted in significant EER enhancement of the modified unit.

  18. High efficiency novel window air conditioner

    DOE PAGESBeta

    Bansal, Pradeep

    2015-01-01

    This paper presents the technical development of a high efficiency window air conditioner. In order to achieve higher energy efficiency ratio (EER), the original capacity of the R410A unit was downgraded by replacing the original compressor with a lower capacity but higher EER compressor, while all heat exchangers and the chassis from the original unit were retained. The other subsequent major modifications included – the AC fan motor being replaced with a brushless high efficiency electronically commuted motor (ECM) motor, the capillary tube being replaced with a needle valve to better control the refrigerant flow and refrigerant set points, andmore » R410A being replaced with drop-in environmentally friendly binary mixture of R32 (85% molar concentration)/R125 (15% molar concentration). All these modifications resulted in significant EER enhancement of the modified unit.« less

  19. Economic comparison of power factor correction by capacitors and high power factor/high-efficiency motors

    SciTech Connect

    Slack, K.D.; Capehart, B.L.

    1998-12-01

    The traditional approach to power factor correction in a facility is to add capacitors to individual loads such as motors and fluorescent lighting circuits, to add a capacitor bank with switching to a major distribution panel, or to add a capacitor bank with switching to the power input panel from the utility lines. Recently it has been shown that careful selection of high-efficiency motors for a facility can result in new motors with a significantly higher power factor than the motors they replaced. This article compares and discusses the cost-effectiveness of installing capacitors on individual motors with the cost-effectiveness of installing high-efficiency, high power factor motors.

  20. Novel Nanophosphors for High Efficiency Fluorescent Lamps

    SciTech Connect

    Alok M. Srivastava

    2005-09-30

    This is the Yearly Report of the Novel Nanophosphors for High Efficiency Fluorescent Lamps, Department of Energy (DOE). The overall goal of this three-year program is to develop novel hybrid phosphors by coating commercially available lamp phosphors with highly stable wide band-gap nanocrystalline phosphors (NCP). The novel hybrid phosphors will increase the efficiency of the fluorescent lamps by up to 32%, enabling total energy savings of 0.26 quads, the reduction in the U.S. energy bill by $6.5 billion and the reduction of the annual carbon emission by 4.1 billion kilogram. The prime technical approach is the development of NCP quantum-splitting phosphor (QSP) and ultra-violet emitting phosphors with quantum efficiencies exceeding that of the conventional phosphors at 185 nm. Our chief achievement, during the current contract period, pertains to the successful synthesis and characterization of coated phosphors. We demonstrated several synthesis techniques for the coating of micron sized commercial phosphors with quantum-splitting and UV emitting nanophosphors. We have also continued our fundamental investigations into the physical processes that determine the quantum efficiency of the nanophosphors and this has further helped codify a set of rules for the host lattice that support efficient quantum splitting and UV emission at room temperature. In this report we summarize the technical work completed under the Program, summarize our findings about the performance limits of the various technologies we investigated, and outline promising paths for future work.

  1. TRIDENT high-energy-density facility experimental capabilities and diagnostics.

    PubMed

    Batha, S H; Aragonez, R; Archuleta, F L; Archuleta, T N; Benage, J F; Cobble, J A; Cowan, J S; Fatherley, V E; Flippo, K A; Gautier, D C; Gonzales, R P; Greenfield, S R; Hegelich, B M; Hurry, T R; Johnson, R P; Kline, J L; Letzring, S A; Loomis, E N; Lopez, F E; Luo, S N; Montgomery, D S; Oertel, J A; Paisley, D L; Reid, S M; Sanchez, P G; Seifter, A; Shimada, T; Workman, J B

    2008-10-01

    The newly upgraded TRIDENT high-energy-density (HED) facility provides high-energy short-pulse laser-matter interactions with powers in excess of 200 TW and energies greater than 120 J. In addition, TRIDENT retains two long-pulse (nanoseconds to microseconds) beams that are available for simultaneous use in either the same experiment or a separate one. The facility's flexibility is enhanced by the presence of two separate target chambers with a third undergoing commissioning. This capability allows the experimental configuration to be optimized by choosing the chamber with the most advantageous geometry and features. The TRIDENT facility also provides a wide range of standard instruments including optical, x-ray, and particle diagnostics. In addition, one chamber has a 10 in. manipulator allowing OMEGA and National Ignition Facility (NIF) diagnostics to be prototyped and calibrated.

  2. TRIDENT high-energy-density facility experimental capabilities and diagnosticsa)

    NASA Astrophysics Data System (ADS)

    Batha, S. H.; Aragonez, R.; Archuleta, F. L.; Archuleta, T. N.; Benage, J. F.; Cobble, J. A.; Cowan, J. S.; Fatherley, V. E.; Flippo, K. A.; Gautier, D. C.; Gonzales, R. P.; Greenfield, S. R.; Hegelich, B. M.; Hurry, T. R.; Johnson, R. P.; Kline, J. L.; Letzring, S. A.; Loomis, E. N.; Lopez, F. E.; Luo, S. N.; Montgomery, D. S.; Oertel, J. A.; Paisley, D. L.; Reid, S. M.; Sanchez, P. G.; Seifter, A.; Shimada, T.; Workman, J. B.

    2008-10-01

    The newly upgraded TRIDENT high-energy-density (HED) facility provides high-energy short-pulse laser-matter interactions with powers in excess of 200TW and energies greater than 120J. In addition, TRIDENT retains two long-pulse (nanoseconds to microseconds) beams that are available for simultaneous use in either the same experiment or a separate one. The facility's flexibility is enhanced by the presence of two separate target chambers with a third undergoing commissioning. This capability allows the experimental configuration to be optimized by choosing the chamber with the most advantageous geometry and features. The TRIDENT facility also provides a wide range of standard instruments including optical, x-ray, and particle diagnostics. In addition, one chamber has a 10in. manipulator allowing OMEGA and National Ignition Facility (NIF) diagnostics to be prototyped and calibrated.

  3. Efficient circuit triggers high-current, high-voltage pulses

    NASA Technical Reports Server (NTRS)

    Green, E. D.

    1964-01-01

    Modified circuit uses diodes to effectively disconnect the charging resistors from the circuit during the discharge cycle. Result is an efficient parallel charging, high voltage pulse modulator with low voltage rating of components.

  4. Recent progress on LULI high power laser facilities

    NASA Astrophysics Data System (ADS)

    Zou, J. P.; Blanc, C. L.; Audebert, P.; Janicot, S.; Sautivet, A. M.; Martin, L.; Sauteret, C.; Paillard, J. L.; Jacquemot, S.; Amiranoff, F.

    2008-05-01

    LULI is actively involved in laser developments to continuously upgrade its facilities. We will report on the optimization of the dynamic wavefront control for the LULI2000 facility and on the first phase of the LULI PW project (200J, 1ps). We will also present the ELFIE project, the upgrade of the 100TW system, including an energy enhancement and the development of a short-pulse high-energy OPCPA beam line.

  5. High Efficiency Solar Integrated Roof Membrane Product

    SciTech Connect

    Partyka, Eric; Shenoy, Anil

    2013-05-15

    This project was designed to address the Solar Energy Technology Program objective, to develop new methods to integrate photovoltaic (PV) cells or modules within a building-integrated photovoltaic (BIPV) application that will result in lower installed cost as well as higher efficiencies of the encapsulated/embedded PV module. The technology assessment and development focused on the evaluation and identification of manufacturing technologies and equipment capable of producing such low-cost, high-efficiency, flexible BIPV solar cells on single-ply roofing membranes.

  6. High efficiency compound semiconductor concentrator photovoltaics

    NASA Technical Reports Server (NTRS)

    Borden, P.; Gregory, P.; Saxena, R.; Owen, R.; Moore, O.

    1980-01-01

    Special emphasis was given to the high yield pilot production of packaged AlGaAs/GaAs concentrator solar cells, using organometallic VPE for materials growth, the demonstration of a concentrator module using 12 of these cells which achieved 16.4 percent conversion efficiency at 50 C coolant inlet temperature, and the demonstration of a spectral splitting converter module that achieved in excess of 20 percent efficiency. This converter employed ten silicon and ten AlGaAs cells with a dichroic filter functioning as the beam splitter. A monolithic array of AlGaAs/GaAs solar cells is described.

  7. Highly efficient charged particle veto detector CUP

    NASA Astrophysics Data System (ADS)

    Palacz, M.; Nyberg, J.; Bednarczyk, P.; Dworski, J.; Górska, M.; Iwanicki, J.; Kapusta, M.; Kownacki, J.; Kulczycka, E.; Lagergren, K.; Moszyński, M.; Pieńkowski, L.; Stolarz, A.; Wolski, D.; Ziębliński, M.

    2005-09-01

    A novel, highly efficient, plastic scintillator detector has been constructed. The primary application of the detector is to act as a veto device in heavy-ion-induced fusion-evaporation reactions, in which the structure of proton-rich nuclides is investigated by γ-ray spectroscopy methods. The detector rejects events in which light charged particles, like protons and α particles, are emitted in the evaporation process, facilitating selection of reaction channels associated with emission of only neutrons. The detector was used in a EUROBALL experiment, with achieved efficiencies of 80% and 63% for protons and α particles, respectively. The design of the detector, its performance and limitations are discussed.

  8. Aqueous route to facile, efficient and functional silica coating of metal nanoparticles at room temperature

    NASA Astrophysics Data System (ADS)

    Shah, Kwok Wei; Sreethawong, Thammanoon; Liu, Shu-Hua; Zhang, Shuang-Yuan; Tan, Li Sirh; Han, Ming-Yong

    2014-09-01

    Various metal (Ag, Au, and Pt)@thiol-functionalized silica (SiO2-SH) nanoparticles (NPs) are successfully prepared at room temperature by a facile, efficient, functional, universal and scalable coating process in alcohol-free aqueous solution using pre-hydrolyzed 3-(mercaptopropyl)trimethoxysilane (MPTMS). The controlled pre-hydrolysis of the silane precursor in water and the consecutive condensation processes are the key to achieve the effective and uniform silica coating on metal NPs in aqueous solution. The thickness of the silica shell is tuned by simply varying the coating time. The silica shell can act as an effective protecting layer for Ag NPs in Ag@SiO2-SH NPs under conditions for silica coating in aqueous solution; however, it leads to a directional dissolution of Ag NPs in a more strongly basic ammonia solution. The environmentally friendly silica coating process in water is also applied to prepare highly surface-enhanced Raman scattering (SERS)-active Ag@SiO2-SH NPs with different types of Raman molecules for highly sensitive SERS-based applications in various fields.Various metal (Ag, Au, and Pt)@thiol-functionalized silica (SiO2-SH) nanoparticles (NPs) are successfully prepared at room temperature by a facile, efficient, functional, universal and scalable coating process in alcohol-free aqueous solution using pre-hydrolyzed 3-(mercaptopropyl)trimethoxysilane (MPTMS). The controlled pre-hydrolysis of the silane precursor in water and the consecutive condensation processes are the key to achieve the effective and uniform silica coating on metal NPs in aqueous solution. The thickness of the silica shell is tuned by simply varying the coating time. The silica shell can act as an effective protecting layer for Ag NPs in Ag@SiO2-SH NPs under conditions for silica coating in aqueous solution; however, it leads to a directional dissolution of Ag NPs in a more strongly basic ammonia solution. The environmentally friendly silica coating process in water is also

  9. High efficiency, low cost scrubber upgrades

    SciTech Connect

    Klingspor, J.S.; Walters, M.

    1998-07-01

    ABB introduced the LS-2 technology; a limestone based wet FGD system, which is capable of producing high purity gypsum from low grade limestone, in late 1995. Drawing from 30,000 MWe of worldwide wet FGD experience, ABB has incorporated several innovations in the new system designed to reduce the overall cost of SO{sub 2} compliance. Collectively, these improvements are referred to as LS-2. The improvements include a compact high efficiency absorber, a simple dry grinding system, a closed coupled flue gas reheat system, and a tightly integrated dewatering system. The compact absorber includes features such a high velocity spray zone, significantly improved gas-liquid contact system, compact reaction tank, and a high velocity mist eliminator. The LS-2 system is being demonstrated at Ohio Edison's Niles Plant at the 130 MWe level, and this turnkey installation was designed and erected in a 20-month period. At Niles, all of the gypsum is sold to a local wallboard manufacturer. Many of the features included in the LS-2 design and demonstrated at Niles can be used to improve the efficiency and operation of existing systems including open spray towers and tray towers. The SO{sub 2} removal efficiency can be significantly improved by installing the high efficiency LS-2 style spray header design and the unique wall rings. The absorber bypass can be eliminated or reduced by including the LS-2 style high velocity mist eliminator. Also, the LS-2 style spray header design combined with wall rings allow for an increase in absorber gas velocity at a maintained or improved performance without the need for costly upgrades of the absorber recycle pumps. the first upgrade using LS-2 technology was done at CPA's Coal Creek Station (2{times}545 MWe). The experience form the scrubber upgrade at Coal Creek is discussed along with operating results.

  10. Methodologies for high efficiency perovskite solar cells

    NASA Astrophysics Data System (ADS)

    Park, Nam-Gyu

    2016-06-01

    Since the report on long-term durable solid-state perovskite solar cell in 2012, perovskite solar cells based on lead halide perovskites having organic cations such as methylammonium CH3NH3PbI3 or formamidinium HC(NH2)2PbI3 have received great attention because of superb photovoltaic performance with power conversion efficiency exceeding 22 %. In this review, emergence of perovskite solar cell is briefly introduced. Since understanding fundamentals of light absorbers is directly related to their photovoltaic performance, opto-electronic properties of organo lead halide perovskites are investigated in order to provide insight into design of higher efficiency perovskite solar cells. Since the conversion efficiency of perovskite solar cell is found to depend significantly on perovskite film quality, methodologies for fabricating high quality perovskite films are particularly emphasized, including various solution-processes and vacuum deposition method.

  11. High efficiency low cost solar cell power

    NASA Technical Reports Server (NTRS)

    Bekey, I.; Blocker, W.

    1978-01-01

    A concept for generating high-efficiency, low-cost, solar-cell power is outlined with reference to solar cell parameters, optical concentrators, and thermal control procedures. A design for a 12.5-kw power module for space operation is discussed noting the optical system, spectrum splitter, light conversion system, cell cooling, power conditioner, and tracking mechanism. It is found that for an unconcentrated array, efficiency approaches 60% when ten or more bandgaps are used. For a 12-band system, a computer program distributed bandgaps for maximum efficiency and equal cell currents. Rigid materials and thin films have been proposed for optical components and prisms, gratings, and dichroic mirrors have been recommended for spectrum splitting. Various radiator concepts are noted including that of Weatherston and Smith (1960) and Hedgepeth and Knapp (1978). The concept may be suitable for the Solar Power Satellite.

  12. High efficiency electrotransformation of Lactobacillus casei.

    PubMed

    Welker, Dennis L; Hughes, Joanne E; Steele, James L; Broadbent, Jeff R

    2015-01-01

    We investigated whether protocols allowing high efficiency electrotransformation of other lactic acid bacteria were applicable to five strains of Lactobacillus casei (12A, 32G, A2-362, ATCC 334 and BL23). Addition of 1% glycine or 0.9 M NaCl during cell growth, limitation of the growth of the cell cultures to OD600 0.6-0.8, pre-electroporation treatment of cells with water or with a lithium acetate (100 mM)/dithiothreitol (10 mM) solution and optimization of electroporation conditions all improved transformation efficiencies. However, the five strains varied in their responses to these treatments. Transformation efficiencies of 10(6) colony forming units μg(-1) pTRKH2 DNA and higher were obtained with three strains which is sufficient for construction of chromosomal gene knock-outs and gene replacements. PMID:25670703

  13. Laboratory Astrophysics on High Power Lasers and Pulsed Power Facilities

    SciTech Connect

    Remington, B A

    2002-02-05

    Over the past decade a new genre of laboratory astrophysics has emerged, made possible by the new high energy density (HED) experimental facilities, such as large lasers, z-pinch generators, and high current particle accelerators. (Remington, 1999; 2000; Drake, 1998; Takabe, 2001) On these facilities, macroscopic collections of matter can be created in astrophysically relevant conditions, and its collective properties measured. Examples of processes and issues that can be experimentally addressed include compressible hydrodynamic mixing, strong shock phenomena, radiative shocks, radiation flow, high Mach-number jets, complex opacities, photoionized plasmas, equations of state of highly compressed matter, and relativistic plasmas. These processes are relevant to a wide range of astrophysical phenomena, such as supernovae and supernova remnants, astrophysical jets, radiatively driven molecular clouds, accreting black holes, planetary interiors, and gamma-ray bursts. These phenomena will be discussed in the context of laboratory astrophysics experiments possible on existing and future HED facilities.

  14. The second generation Singapore high resolution proton beam writing facility

    SciTech Connect

    Kan, J. A. van; Malar, P.; Baysic de Vera, Armin

    2012-02-15

    A new proton beam focusing facility, designed for proton beam writing (PBW) applications has been tested. PBW allows for proximity free structuring of high aspect ratio, high-density 3D nanostructures. The new facility is designed around OM52 compact quadrupole lenses capable of operating in a variety of high demagnification configurations. Performance tests show that proton beams can be focused down to 19.0 x 29.9 nm{sup 2} and single line scans show a beam width of 12.6 nm. The ultimate goal of sub 10 nm structuring with MeV protons will be discussed.

  15. Creation of High Efficient Firefly Luciferase

    NASA Astrophysics Data System (ADS)

    Nakatsu, Toru

    Firefly emits visible yellow-green light. The bioluminescence reaction is carried out by the enzyme luciferase. The bioluminescence of luciferase is widely used as an excellent tool for monitoring gene expression, the measurement of the amount of ATP and in vivo imaging. Recently a study of the cancer metastasis is carried out by in vivo luminescence imaging system, because luminescence imaging is less toxic and more useful for long-term assay than fluorescence imaging by GFP. However the luminescence is much dimmer than fluorescence. Then bioluminescence imaging in living organisms demands the high efficient luciferase which emits near infrared lights or enhances the emission intensity. Here I introduce an idea for creating the high efficient luciferase based on the crystal structure.

  16. Breeding for high water-use efficiency.

    PubMed

    Condon, A G; Richards, R A; Rebetzke, G J; Farquhar, G D

    2004-11-01

    There is a pressing need to improve the water-use efficiency of rain-fed and irrigated crop production. Breeding crop varieties with higher water-use efficiency is seen as providing part of the solution. Three key processes can be exploited in breeding for high water-use efficiency: (i) moving more of the available water through the crop rather than it being wasted as evaporation from the soil surface or drainage beyond the root zone or being left behind in the root zone at harvest; (ii) acquiring more carbon (biomass) in exchange for the water transpired by the crop, i.e. improving crop transpiration efficiency; (iii) partitioning more of the achieved biomass into the harvested product. The relative importance of any one of these processes will vary depending on how water availability varies during the crop cycle. However, these three processes are not independent. Targeting specific traits to improve one process may have detrimental effects on the other two, but there may also be positive interactions. Progress in breeding for improved water-use efficiency of rain-fed wheat is reviewed to illustrate the nature of some of these interactions and to highlight opportunities that may be exploited in other crops as well as potential pitfalls. For C3 species, measuring carbon isotope discrimination provides a powerful means of improving water-use efficiency of leaf gas exchange, but experience has shown that improvements in leaf-level water-use efficiency may not always translate into higher crop water-use efficiency or yield. In fact, the reverse has frequently been observed. Reasons for this are explored in some detail. Crop simulation modelling can be used to assess the likely impact on water-use efficiency and yield of changing the expression of traits of interest. Results of such simulations indicate that greater progress may be achieved by pyramiding traits so that potential negative effects of individual traits are neutralized. DNA-based selection techniques may

  17. High energy efficient solid state laser sources

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1987-01-01

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

  18. High Efficiency Thermoelectric Materials and Devices

    NASA Technical Reports Server (NTRS)

    Kochergin, Vladimir (Inventor)

    2013-01-01

    Growth of thermoelectric materials in the form of quantum well super-lattices on three-dimensionally structured substrates provide the means to achieve high conversion efficiency of the thermoelectric module combined with inexpensiveness of fabrication and compatibility with large scale production. Thermoelectric devices utilizing thermoelectric materials in the form of quantum well semiconductor super-lattices grown on three-dimensionally structured substrates provide improved thermoelectric characteristics that can be used for power generation, cooling and other applications..

  19. High-Pressure Gaseous Burner (HPGB) Facility Became Operational

    NASA Technical Reports Server (NTRS)

    Nguyen, Quang-Viet

    2003-01-01

    A gas-fueled high-pressure combustion facility with optical access, developed over the last 3 years, is now collecting research data in a production mode. The High-Pressure Gaseous Burner (HPGB) rig at the NASA Glenn Research Center can operate at sustained pressures up to 60 atm with a variety of gaseous fuels and liquid jet fuel. The facility is unique because it is the only continuous-flow, hydrogen-capable 60-atm rig in the world with optical access. It will provide researchers with new insights into flame conditions that simulate the environment inside the ultra-high-pressure-ratio combustion chambers of tomorrow s advanced aircraft engines. The facility provides optical access to the flame zone through four fused-silica optical windows, enabling the calibration of nonintrusive optical diagnostics to measure chemical species and temperature. The data from the HPGB rig enable the validation of numerical codes that simulate gas turbine combustors.

  20. High efficiency silicon concentrator solar cells

    NASA Astrophysics Data System (ADS)

    Zhao, Jianhua

    1990-06-01

    Techniques were investigated for improving the energy conversion efficiency of silicon concentrator solar cells. This aim was achieved with the demonstration of bifacially contacted silicon concentrator solar cells of markedly superior performance. An additional achievement was the demonstration of substantial improvements in the performance of non-concentrating, one-sun cells. The improvements in the one-sun cell area were achieved by optimization of the Passivated Emitter Solar Cell (PESC) technology. Aluminum gettering and emitter surface oxide-passivation played key roles for the PESC cells. The optimized PESC one-sun cell demonstrated an independently confirmed efficiency of 21.4 percent. The optimized PESC technology was also successfully applied to the fabrication of silicon concentrator cells on low resistivity substrates. The effects of metal contact resistance and heavy phosphorus diffusion were areas requiring additional careful investigation in this case. A concentrator cell after optimization demonstrated 23.4 percent efficiency at 100 suns, again independently confirmed. Although very high by normal standards, the efficiency was limited by the trade-off of the resistance and the shading of the front metal fingers. The need for the trade-off was eliminated by the application of prismatic covers, which steer the incident light onto the cell active areas avoiding metal fingers. The Passivated Emitter and Rear Cells (PERC) incorporating TCA (trichloro-ethane) processing improved the one-sun cell efficiency further to 21.8 percent. The improvement came from low recombination at surfaces and in the bulk resulting from the TCA processing and from reduced rear contact area. Antireflection coatings and prismatic cover design were also theoretically optimized. When combined with light trapping techniques, 27 percent efficiency silicon concentrator cell will be obtained with this approach in the near future.

  1. High level radioactive waste management facility design criteria

    SciTech Connect

    Sheikh, N.A.; Salaymeh, S.R.

    1993-10-01

    This paper discusses the engineering systems for the structural design of the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS). At the DWPF, high level radioactive liquids will be mixed with glass particles and heated in a melter. This molten glass will then be poured into stainless steel canisters where it will harden. This process will transform the high level waste into a more stable, manageable substance. This paper discuss the structural design requirements for this unique one of a kind facility. A special emphasis will be concentrated on the design criteria pertaining to earthquake, wind and tornado, and flooding.

  2. High efficiency crystalline silicon solar cells

    NASA Technical Reports Server (NTRS)

    Sah, C. Tang

    1986-01-01

    A review of the entire research program since its inception ten years ago is given. The initial effort focused on the effects of impurities on the efficiency of silicon solar cells to provide figures of maximum allowable impurity density for efficiencies up to about 16 to 17%. Highly accurate experimental techniques were extended to characterize the recombination properties of the residual imputities in the silicon solar cell. A numerical simulator of the solar cell was also developed, using the Circuit Technique for Semiconductor Analysis. Recent effort focused on the delineation of the material and device parameters which limited the silicon efficiency to below 20% and on an investigation of cell designs to break the 20% barrier. Designs of the cell device structure and geometry can further reduce recombination losses as well as the sensitivity and criticalness of the fabrication technology required to exceed 20%. Further research is needed on the fundamental characterization of the carrier recombination properties at the chemical impurity and physical defect centers. It is shown that only single crystalline silicon cell technology can be successful in attaining efficiencies greater than 20%.

  3. Highly efficient fully transparent inverted OLEDs

    NASA Astrophysics Data System (ADS)

    Meyer, J.; Winkler, T.; Hamwi, S.; Schmale, S.; Kröger, M.; Görrn, P.; Johannes, H.-H.; Riedl, T.; Lang, E.; Becker, D.; Dobbertin, T.; Kowalsky, W.

    2007-09-01

    One of the unique selling propositions of OLEDs is their potential to realize highly transparent devices over the visible spectrum. This is because organic semiconductors provide a large Stokes-Shift and low intrinsic absorption losses. Hence, new areas of applications for displays and ambient lighting become accessible, for instance, the integration of OLEDs into the windshield or the ceiling of automobiles. The main challenge in the realization of fully transparent devices is the deposition of the top electrode. ITO is commonly used as transparent bottom anode in a conventional OLED. To obtain uniform light emission over the entire viewing angle and a low series resistance, a TCO such as ITO is desirable as top contact as well. However, sputter deposition of ITO on top of organic layers causes damage induced by high energetic particles and UV radiation. We have found an efficient process to protect the organic layers against the ITO rf magnetron deposition process of ITO for an inverted OLED (IOLED). The inverted structure allows the integration of OLEDs in more powerful n-channel transistors used in active matrix backplanes. Employing the green electrophosphorescent material Ir(ppy) 3 lead to IOLED with a current efficiency of 50 cd/A and power efficiency of 24 lm/W at 100 cd/m2. The average transmittance exceeds 80 % in the visible region. The on-set voltage for light emission is lower than 3 V. In addition, by vertical stacking we achieved a very high current efficiency of more than 70 cd/A for transparent IOLED.

  4. The Grenoble High Magnetic Field Laboratory as a user facility

    NASA Astrophysics Data System (ADS)

    Debray, F.; Jongbloets, H.; Joss, W.; Martinez, G.; Mossang, E.; Picoche, J. C.; Plante, A.; Rub, P.; Sala, P.; Wyder, P.

    2001-01-01

    The Grenoble High Magnetic Field Laboratory (GHMFL), run jointly by the Centre National de la Recherche Scientifique (CNRS, France) and the Max-Planck Gesellschaft (MPG, Germany) is a leading laboratory pursuing research in the highest static magnetic fields technically feasible. The laboratory maintains strong in-house research activities and partly operates as a user facility for qualified external researchers. It has developed highly sophisticated instrumentation for specific use under high magnetic fields, including transport, magnetization, visible and infrared optical measurements at low temperatures and/or high pressures, EPR and NMR investigations in high magnetic fields. The laboratory delivers around 5000 h of magnet time per year. Access for users to the high magnetic field facility is supported by the European Union, in the framework of the Human Potential Program : “Transnational Access to Major Research Infrastructures”.We give an overview of the technical aspects of the facility and of the laboratory activities as a facility over the last few years. The general organization of the user community and repartition between countries will also be reviewed.

  5. High Efficiency Colloidal Quantum Dot Phosphors

    SciTech Connect

    Kahen, Keith

    2013-12-31

    The project showed that non-Cd containing, InP-based nanocrystals (semiconductor materials with dimensions of ~6 nm) have high potential for enabling next-generation, nanocrystal-based, on chip phosphors for solid state lighting. Typical nanocrystals fall short of the requirements for on chip phosphors due to their loss of quantum efficiency under the operating conditions of LEDs, such as, high temperature (up to 150 °C) and high optical flux (up to 200 W/cm2). The InP-based nanocrystals invented during this project maintain high quantum efficiency (>80%) in polymer-based films under these operating conditions for emission wavelengths ranging from ~530 to 620 nm. These nanocrystals also show other desirable attributes, such as, lack of blinking (a common problem with nanocrystals which limits their performance) and no increase in the emission spectral width from room to 150 °C (emitters with narrower spectral widths enable higher efficiency LEDs). Prior to these nanocrystals, no nanocrystal system (regardless of nanocrystal type) showed this collection of properties; in fact, other nanocrystal systems are typically limited to showing only one desirable trait (such as high temperature stability) but being deficient in other properties (such as high flux stability). The project showed that one can reproducibly obtain these properties by generating a novel compositional structure inside of the nanomaterials; in addition, the project formulated an initial theoretical framework linking the compositional structure to the list of high performance optical properties. Over the course of the project, the synthetic methodology for producing the novel composition was evolved to enable the synthesis of these nanomaterials at a cost approximately equal to that required for forming typical conventional nanocrystals. Given the above results, the last major remaining step prior to scale up of the nanomaterials is to limit the oxidation of these materials during the tens of

  6. New high-efficiency silicon solar cells

    NASA Technical Reports Server (NTRS)

    Daud, T.; Crotty, G. T.

    1985-01-01

    A design for silicon solar cells was investigated as an approach to increasing the cell open-circuit voltage and efficiency for flat-plate terrestrial photovoltaic applications. This deviates from past designs, where either the entire front surface of the cell is covered by a planar junction or the surface is textured before junction formation, which results in an even greater (up to 70%) junction area. The heavily doped front region and the junction space charge region are potential areas of high recombination for generated and injected minority carriers. The design presented reduces junction area by spreading equidiameter dot junctions across the surface of the cell, spaced about a diffusion length or less from each other. Various dot diameters and spacings allowed variations in total junction area. A simplified analysis was done to obtain a first-order design optimization. Efficiencies of up to 19% can be obtained. Cell fabrication involved extra masking steps for selective junction diffusion, and made surface passivation a key element in obtaining good collection. It also involved photolithography, with line widths down to microns. A method is demonstrated for achieving potentially high open-circuit voltages and solar-cell efficiencies.

  7. HIGH-EFFICIENCY AUTONOMOUS LASER ADAPTIVE OPTICS

    SciTech Connect

    Baranec, Christoph; Riddle, Reed; Tendulkar, Shriharsh; Hogstrom, Kristina; Bui, Khanh; Dekany, Richard; Kulkarni, Shrinivas; Law, Nicholas M.; Ramaprakash, A. N.; Burse, Mahesh; Chordia, Pravin; Das, Hillol; Punnadi, Sujit

    2014-07-20

    As new large-scale astronomical surveys greatly increase the number of objects targeted and discoveries made, the requirement for efficient follow-up observations is crucial. Adaptive optics imaging, which compensates for the image-blurring effects of Earth's turbulent atmosphere, is essential for these surveys, but the scarcity, complexity and high demand of current systems limit their availability for following up large numbers of targets. To address this need, we have engineered and implemented Robo-AO, a fully autonomous laser adaptive optics and imaging system that routinely images over 200 objects per night with an acuity 10 times sharper at visible wavelengths than typically possible from the ground. By greatly improving the angular resolution, sensitivity, and efficiency of 1-3 m class telescopes, we have eliminated a major obstacle in the follow-up of the discoveries from current and future large astronomical surveys.

  8. High efficiency ion beam accelerator system

    NASA Technical Reports Server (NTRS)

    Aston, G.

    1981-01-01

    An ion accelerator system that successfully combines geometrical and electrostatic focusing principles is presented. This accelerator system uses thin, concave, multiple-hole, closely spaced graphite screen and focusing grids which are coupled to single slot accelerator and decelerator grids to provide high ion extraction efficiency and good focusing. Tests with the system showed a substantial improvement in ion beam current density and collimation as compared with a Pierce electrode configuration. Durability of the thin graphite screen and focusing grids has been proven, and tests are being performed to determine the minimum screen and focusing grid spacing and thickness required to extract the maximum reliable beam current density. Compared with present neutral beam injector accelerator systems, this one has more efficient ion extraction, easier grid alignment, easier fabrication, a less cumbersome design, and the capacity to be constructed in a modular fashion. Conceptual neutral beam injector designs using this modular approach have electrostatic beam deflection plates downstream of each module.

  9. Highly efficient Raman distributed feedback fibre lasers.

    PubMed

    Shi, Jindan; Alam, Shaif-ul; Ibsen, Morten

    2012-02-27

    We demonstrate highly efficient Raman distributed feedback (DFB) fibre lasers for the first time with up to 1.6 W of continuous wave (CW) output power. The DFB Bragg gratings are written directly into two types of commercially available passive germano-silica fibres. Two lasers of 30 cm length are pumped with up to 15 W of CW power at 1068 nm. The threshold power is ~2 W for a Raman-DFB (R-DFB) laser written in standard low-NA fibre, and only ~1 W for a laser written in a high-NA fibre, both of which oscillate in a narrow linewidth of <0.01 nm at ~1117 nm and ~1109 nm, respectively. The slope efficiencies are ~74% and ~93% with respect to absorbed pump power in the low-NA fibre and high-NA fibre respectively. Such high conversion efficiency suggests that very little energy is lost in the form of heat through inefficient energy transfer. Our results are supported by numerical simulations, and furthermore open up for the possibility of having narrow linewidth all-fibre laser sources in wavelength bands not traditionally covered by rare-earth doped silica fibres. Simulations also imply that this technology has the potential to produce even shorter R-DFB laser devices at the centimetre-level and with mW-level thresholds, if Bragg gratings formed in fibre materials with higher intrinsic Raman gain coefficient than silica are used. These materials include for example tellurite or chalcogenide glasses. Using glasses like these would also open up the possibility of having narrow linewidth fibre sources with DFB laser oscillating much further into the IR than what currently is possible with rare-earth doped silica glasses. PMID:22418313

  10. Highly efficient Raman distributed feedback fibre lasers.

    PubMed

    Shi, Jindan; Alam, Shaif-ul; Ibsen, Morten

    2012-02-27

    We demonstrate highly efficient Raman distributed feedback (DFB) fibre lasers for the first time with up to 1.6 W of continuous wave (CW) output power. The DFB Bragg gratings are written directly into two types of commercially available passive germano-silica fibres. Two lasers of 30 cm length are pumped with up to 15 W of CW power at 1068 nm. The threshold power is ~2 W for a Raman-DFB (R-DFB) laser written in standard low-NA fibre, and only ~1 W for a laser written in a high-NA fibre, both of which oscillate in a narrow linewidth of <0.01 nm at ~1117 nm and ~1109 nm, respectively. The slope efficiencies are ~74% and ~93% with respect to absorbed pump power in the low-NA fibre and high-NA fibre respectively. Such high conversion efficiency suggests that very little energy is lost in the form of heat through inefficient energy transfer. Our results are supported by numerical simulations, and furthermore open up for the possibility of having narrow linewidth all-fibre laser sources in wavelength bands not traditionally covered by rare-earth doped silica fibres. Simulations also imply that this technology has the potential to produce even shorter R-DFB laser devices at the centimetre-level and with mW-level thresholds, if Bragg gratings formed in fibre materials with higher intrinsic Raman gain coefficient than silica are used. These materials include for example tellurite or chalcogenide glasses. Using glasses like these would also open up the possibility of having narrow linewidth fibre sources with DFB laser oscillating much further into the IR than what currently is possible with rare-earth doped silica glasses.

  11. Development of manufacturing capability for high-concentration, high-efficiency silicon solar cells

    SciTech Connect

    Sinton, R.A.; Verlinden, P.J.; Crane, R.A.; Swanson, R.N.

    1996-10-01

    This report presents a summary of the major results from a program to develop a manufacturable, high-efficiency silicon concentrator solar cell and a cost-effective manufacturing facility. The program was jointly funded by the Electric Power Research Institute, Sandia National Laboratories through the Concentrator Initiative, and SunPower Corporation. The key achievements of the program include the demonstration of 26%-efficient silicon concentrator solar cells with design-point (20 W/cm{sup 2}) efficiencies over 25%. High-performance front-surface passivations; that were developed to achieve this result were verified to be absolutely stable against degradation by 475 days of field exposure at twice the design concentration. SunPower demonstrated pilot production of more than 1500 of these cells. This cell technology was also applied to pilot production to supply 7000 17.7-cm{sup 2} one-sun cells (3500 yielded wafers) that demonstrated exceptional quality control. The average efficiency of 21.3% for these cells approaches the peak efficiency ever demonstrated for a single small laboratory cell within 2% (absolute). Extensive cost models were developed through this program and calibrated by the pilot-production project. The production levels achieved indicate that SunPower could produce 7-10 MW of concentrator cells per year in the current facility based upon the cell performance demonstrated during the program.

  12. High Power RF Test Facility at the SNS

    SciTech Connect

    Y.W. Kang; D.E. Anderson; I.E. Campisi; M. Champion; M.T. Crofford; R.E. Fuja; P.A. Gurd; S. Hasan; K.-U. Kasemir; M.P. McCarthy; D. Stout; J.Y. Tang; A.V. Vassioutchenko; M. Wezensky; G.K. Davis; M. A. Drury; T. Powers; M. Stirbet

    2005-05-16

    RF Test Facility has been completed in the SNS project at ORNL to support test and conditioning operation of RF subsystems and components. The system consists of two transmitters for two klystrons powered by a common high voltage pulsed converter modulator that can provide power to two independent RF systems. The waveguides are configured with WR2100 and WR1150 sizes for presently used frequencies: 402.5 MHz and 805 MHz. Both 402.5 MHz and 805 MHz systems have circulator protected klystrons that can be powered by the modulator capable of delivering 11 MW peak and 1 MW average power. The facility has been equipped with computer control for various RF processing and complete dual frequency operation. More than forty 805 MHz fundamental power couplers for the SNS superconducting linac (SCL) cavities have been RF conditioned in this facility. The facility provides more than 1000 ft2 floor area for various test setups. The facility also has a shielded cave area that can support high power tests of normal conducting and superconducting accelerating cavities and components.

  13. Efficiency of U.S. Dialysis Centers: An Updated Examination of Facility Characteristics That Influence Production of Dialysis Treatments

    PubMed Central

    Shreay, Sanatan; Ma, Martin; McCluskey, Jill; Mittelhammer, Ron C; Gitlin, Matthew; Stephens, J Mark

    2014-01-01

    Objective To explore the relative efficiency of dialysis facilities in the United States and identify factors that are associated with efficiency in the production of dialysis treatments. Data Sources/Study Setting Medicare cost report data from 4,343 free-standing dialysis facilities in the United States that offered in-center hemodialysis in 2010. Study Design A cross-sectional, facility-level retrospective database analysis, utilizing data envelopment analysis (DEA) to estimate facility efficiency. Data Collection/Extraction Methods Treatment data and cost and labor inputs of dialysis treatments were obtained from 2010 Medicare Renal Cost Reports. Demographic data were obtained from the 2010 U.S. Census. Principal Findings Only 26.6 percent of facilities were technically efficient. Neither the intensity of market competition nor the profit status of the facility had a significant effect on efficiency. Facilities that were members of large chains were less likely to be efficient. Cost and labor savings due to changes in drug protocols had little effect on overall dialysis center efficiency. Conclusions The majority of free-standing dialysis facilities in the United States were functioning in a technically inefficient manner. As payment systems increasingly employ capitation and bundling provisions, these institutions will need to evaluate their efficiency to remain competitive. PMID:24237043

  14. Facile and Efficient Preparation of Tri-component Fluorescent Glycopolymers via RAFT-controlled Polymerization

    PubMed Central

    Wang, Wei; Lester, John M.; Amorosa, Anthony E.; Chance, Deborah L.; Mossine, Valeri V.; Mawhinney, Thomas P.

    2015-01-01

    Synthetic glycopolymers are instrumental and versatile tools used in various biochemical and biomedical research fields. An example of a facile and efficient synthesis of well-controlled fluorescent statistical glycopolymers using reversible addition-fragmentation chain-transfer (RAFT)-based polymerization is demonstrated. The synthesis starts with the preparation of β-galactose-containing glycomonomer 2-lactobionamidoethyl methacrylamide obtained by reaction of lactobionolactone and N-(2-aminoethyl) methacrylamide (AEMA). 2-Gluconamidoethyl methacrylamide (GAEMA) is used as a structural analog lacking a terminal β-galactoside. The following RAFT-mediated copolymerization reaction involves three different monomers: N-(2-hydroxyethyl) acrylamide as spacer, AEMA as target for further fluorescence labeling, and the glycomonomers. Tolerant of aqueous systems, the RAFT agent used in the reaction is (4-cyanopentanoic acid)-4-dithiobenzoate. Low dispersities (≤1.32), predictable copolymer compositions, and high reproducibility of the polymerizations were observed among the products. Fluorescent polymers are obtained by modifying the glycopolymers with carboxyfluorescein succinimidyl ester targeting the primary amine functional groups on AEMA. Lectin-binding specificities of the resulting glycopolymers are verified by testing with corresponding agarose beads coated with specific glycoepitope recognizing lectins. Because of the ease of the synthesis, the tight control of the product compositions and the good reproducibility of the reaction, this protocol can be translated towards preparation of other RAFT-based glycopolymers with specific structures and compositions, as desired. PMID:26132587

  15. A rapid, efficient, and facile solution for dental hypersensitivity: The tannin-iron complex.

    PubMed

    Oh, Dongyeop X; Prajatelistia, Ekavianty; Ju, Sung-Won; Jeong Kim, Hyo; Baek, Soo-Jin; Joon Cha, Hyung; Ho Jun, Sang; Ahn, Jin-Soo; Soo Hwang, Dong

    2015-01-01

    Dental hypersensitivity due to exposure of dentinal tubules under the enamel layer to saliva is a very popular and highly elusive technology priority in dentistry. Blocking water flow within exposed dentinal tubules is a key principle for curing dental hypersensitivity. Some salts used in "at home" solutions remineralize the tubules inside by concentrating saliva ingredients. An "in-office" option of applying dense resin sealants on the tubule entrance has only localized effects on well-defined sore spots. We report a self-assembled film that was formed by facile, rapid (4 min), and efficient (approximately 0.5 g/L concentration) dip-coating of teeth in an aqueous solution containing a tannic acid-iron(III) complex. It quickly and effectively occluded the dentinal tubules of human teeth. It withstood intense tooth brushing and induced hydroxyapatite remineralisation within the dentinal tubules. This strategy holds great promise for future applications as an effective and user-friendly desensitizer for managing dental hypersensitivity. PMID:26039461

  16. A rapid, efficient, and facile solution for dental hypersensitivity: The tannin–iron complex

    PubMed Central

    Oh, Dongyeop X.; Prajatelistia, Ekavianty; Ju, Sung-Won; Jeong Kim, Hyo; Baek, Soo-Jin; Joon Cha, Hyung; Ho Jun, Sang; Ahn, Jin-Soo; Soo Hwang, Dong

    2015-01-01

    Dental hypersensitivity due to exposure of dentinal tubules under the enamel layer to saliva is a very popular and highly elusive technology priority in dentistry. Blocking water flow within exposed dentinal tubules is a key principle for curing dental hypersensitivity. Some salts used in “at home” solutions remineralize the tubules inside by concentrating saliva ingredients. An “in-office” option of applying dense resin sealants on the tubule entrance has only localized effects on well-defined sore spots. We report a self-assembled film that was formed by facile, rapid (4 min), and efficient (approximately 0.5 g/L concentration) dip-coating of teeth in an aqueous solution containing a tannic acid–iron(III) complex. It quickly and effectively occluded the dentinal tubules of human teeth. It withstood intense tooth brushing and induced hydroxyapatite remineralisation within the dentinal tubules. This strategy holds great promise for future applications as an effective and user-friendly desensitizer for managing dental hypersensitivity. PMID:26039461

  17. High Quantum Efficiency OLED Lighting Systems

    SciTech Connect

    Shiang, Joseph

    2011-09-30

    The overall goal of the program was to apply improvements in light outcoupling technology to a practical large area plastic luminaire, and thus enable the product vision of an extremely thin form factor high efficiency large area light source. The target substrate was plastic and the baseline device was operating at 35 LPW at the start of the program. The target LPW of the program was a >2x improvement in the LPW efficacy and the overall amount of light to be delivered was relatively high 900 lumens. Despite the extremely difficult challenges associated with scaling up a wet solution process on plastic substrates, the program was able to make substantial progress. A small molecule wet solution process was successfully implemented on plastic substrates with almost no loss in efficiency in transitioning from the laboratory scale glass to large area plastic substrates. By transitioning to a small molecule based process, the LPW entitlement increased from 35 LPW to 60 LPW. A further 10% improvement in outcoupling efficiency was demonstrated via the use of a highly reflecting cathode, which reduced absorptive loss in the OLED device. The calculated potential improvement in some cases is even larger, ~30%, and thus there is considerable room for optimism in improving the net light coupling efficacy, provided absorptive loss mechanisms are eliminated. Further improvements are possible if scattering schemes such as the silver nanowire based hard coat structure are fully developed. The wet coating processes were successfully scaled to large area plastic substrate and resulted in the construction of a 900 lumens luminaire device.

  18. New line of high efficiency turbochargers

    SciTech Connect

    Chellini, R,

    1994-11-01

    The French firm Hispano Suiza has recently introduced the first of a new family of high-efficiency turbochargers. The design objectives for these turbochargers is to combine the most advanced technology in both the compressor and turbine components. The HS 5800 New Generation Turbocharger is suited for diesel engines in the 1700-3000 kW power range for a single turbocharger unit. When the HS 4800 and HS 6800 sizes are introduced the line will cover a range of engines from 1200 to 9000 kW. 5 figs.

  19. Replacement of Lighting Fixtures with LED Energy Efficient Lights at the Parking Facility, Milwaukee, Wisconsin

    SciTech Connect

    David Brien

    2012-06-21

    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.

  20. Optimization of a high efficiency free electron laser amplifier

    NASA Astrophysics Data System (ADS)

    Schneidmiller, E. A.; Yurkov, M. V.

    2015-03-01

    The free electron laser (FEL) amplifier is implemented in x-ray FEL facilities to generate short wavelength radiation. The problem of an efficiency increase of an FEL amplifier is now of great practical importance. The technique of undulator tapering in the postsaturation regime is used at the existing x-ray FELs LCLS, SACLA and FERMI, and is planned for use at FLASH, European XFEL, Swiss FEL, and PAL XFEL. There are also discussions on the future of high peak and average power FELs for scientific and industrial applications. In this paper we perform a detailed analysis of the tapering strategies for high power seeded FEL amplifiers. Analysis of the radiation properties from the modulated electron beam and application of similarity techniques allows us to derive the universal law of the undulator tapering.

  1. Efficient and facile synthesis of acrylamide libraries for protein-guided tethering.

    PubMed

    Allen, Charlotte E; Curran, Peter R; Brearley, Andrew S; Boissel, Valerie; Sviridenko, Lilya; Press, Neil J; Stonehouse, Jeffrey P; Armstrong, Alan

    2015-02-01

    A kinetic template-guided tethering (KTGT) strategy has been developed for the site-directed discovery of fragments that bind to defined protein surfaces, where acrylamide-modified fragments can be irreversibly captured in a protein-templated conjugate addition reaction. Herein, an efficient and facile method is reported for the preparation of acrylamide libraries from a diverse range of amine fragments using a solid-supported quaternary amine base.

  2. Development of a Large Scale, High Speed Wheel Test Facility

    NASA Technical Reports Server (NTRS)

    Kondoleon, Anthony; Seltzer, Donald; Thornton, Richard; Thompson, Marc

    1996-01-01

    Draper Laboratory, with its internal research and development budget, has for the past two years been funding a joint effort with the Massachusetts Institute of Technology (MIT) for the development of a large scale, high speed wheel test facility. This facility was developed to perform experiments and carry out evaluations on levitation and propulsion designs for MagLev systems currently under consideration. The facility was developed to rotate a large (2 meter) wheel which could operate with peripheral speeds of greater than 100 meters/second. The rim of the wheel was constructed of a non-magnetic, non-conductive composite material to avoid the generation of errors from spurious forces. A sensor package containing a multi-axis force and torque sensor mounted to the base of the station, provides a signal of the lift and drag forces on the package being tested. Position tables mounted on the station allow for the introduction of errors in real time. A computer controlled data acquisition system was developed around a Macintosh IIfx to record the test data and control the speed of the wheel. This paper describes the development of this test facility. A detailed description of the major components is presented. Recently completed tests carried out on a novel Electrodynamic (EDS) suspension system, developed by MIT as part of this joint effort are described and presented. Adaptation of this facility for linear motor and other propulsion and levitation testing is described.

  3. High performance construction materials for treatment, storage, and disposal facilities

    SciTech Connect

    Porter, C.L.

    1996-12-31

    Mixed hazardous/radioactive waste treatment, storage, and disposal (TSD) facilities are often required to either withstand harsh service environments or in the case of disposal facilities exhibit an extremely long service life. The default construction material, Portland cement based concrete (PCC) does not always meet the challenge. For example, many radioactive waste processing facilities are constructed with PCC and then lined with stainless steel. The stainless steel liner is added to provide a surface which can be decontaminated. Installation of the stainless steel liner is both expensive and labor intensive. Similarly, hazardous waste facilities generally require concrete surfaces to be lined with a material that reduces the permeability of the concrete and provides resistance to the harsh chemical environment prevalent in such facilities. This paper is a highly condensed report of the results of a research effort designed to expand the engineering knowledge on two alternate materials which exhibit properties that would allow them to replace the stainless steel lined concrete combination. The two materials are: (1) ICOM, a composite concrete made from a proprietary blend of resins, corrosion-resistant fillers and fine aggregates, and (2) sulfur concrete (SC) made from sulfur polymer cement (SPC). Both materials meet or exceed the mechanical and structural properties of PCC, with the added characteristic of impermeability. The experimental results which are briefly summarized below indicate that these materials are good candidates for applications where a PCC structure has traditionally required supplemental liners due to the poor performance of the PCC alone.

  4. High-Aperture-Efficiency Horn Antenna

    NASA Technical Reports Server (NTRS)

    Pickens, Wesley; Hoppe, Daniel; Epp, Larry; Kahn, Abdur

    2005-01-01

    A horn antenna (see Figure 1) has been developed to satisfy requirements specific to its use as an essential component of a high-efficiency Ka-band amplifier: The combination of the horn antenna and an associated microstrip-patch antenna array is required to function as a spatial power divider that feeds 25 monolithic microwave integrated-circuit (MMIC) power amplifiers. The foregoing requirement translates to, among other things, a further requirement that the horn produce a uniform, vertically polarized electromagnetic field in its patches identically so that the MMICs can operate at maximum efficiency. The horn is fed from a square waveguide of 5.9436-mm-square cross section via a transition piece. The horn features cosine-tapered, dielectric-filled longitudinal corrugations in its vertical walls to create a hard boundary condition: This aspect of the horn design causes the field in the horn aperture to be substantially vertically polarized and to be nearly uniform in amplitude and phase. As used here, cosine-tapered signifies that the depth of the corrugations is a cosine function of distance along the horn. Preliminary results of finite-element simulations of performance have shown that by virtue of the cosine taper the impedance response of this horn can be expected to be better than has been achieved previously in a similar horn having linearly tapered dielectric- filled longitudinal corrugations. It is possible to create a hard boundary condition by use of a single dielectric-filled corrugation in each affected wall, but better results can be obtained with more corrugations. Simulations were performed for a one- and a three-corrugation cosine-taper design. For comparison, a simulation was also performed for a linear- taper design (see Figure 2). The three-corrugation design was chosen to minimize the cost of fabrication while still affording acceptably high performance. Future designs using more corrugations per wavelength are expected to provide better

  5. Vacuum MOCVD fabrication of high efficience cells

    NASA Technical Reports Server (NTRS)

    Partain, L. D.; Fraas, L. M.; Mcleod, P. S.; Cape, J. A.

    1985-01-01

    Vacuum metal-organic-chemical-vapor-deposition (MOCVD) is a new fabrication process with improved safety and easier scalability due to its metal rather than glass construction and its uniform multiport gas injection system. It uses source materials more efficiently than other methods because the vacuum molecular flow conditions allow the high sticking coefficient reactants to reach the substrates as undeflected molecular beams and the hot chamber walls cause the low sticking coefficient reactants to bounce off the walls and interact with the substrates many times. This high source utilization reduces the materials costs power device and substantially decreases the amounts of toxic materials that must be handled as process effluents. The molecular beams allow precise growth control. With improved source purifications, vacuum MOCVD has provided p GaAs layers with 10-micron minority carrier diffusion lengths and GaAs and GaAsSb solar cells with 20% AMO efficiencies at 59X and 99X sunlight concentration ratios. Mechanical stacking has been identified as the quickest, most direct and logical path to stacked multiple-junction solar cells that perform better than the best single-junction devices. The mechanical stack is configured for immediate use in solar arrays and allows interconnections that improve the system end-of-life performance in space.

  6. Efficient high-permeability fracturing offshore

    SciTech Connect

    Phillipi, M.; Farabee, M.

    1996-12-31

    Offshore operators can more efficiently and effectively perform high-permeability and conventional hydraulic fracture treatments by blending treatment slurries under microprocessor control, adding undiluted acid on-the-fly, and altering sand concentrations and other slurry properties instantaneously. A two-skid system has been designed with these considerations in mind. The system, which can be shipped efficiently in ISO containers, has been tested on fluids up to 210-cp viscosity and can step or ramp sand concentrations up to a maximum of 20 lb/gal. All additives, including acid treatments, are added on-the-fly; leftover additives and acids may be stored for future jobs. The system may be applied in most conditions, including offshore wells requiring conventional or high-permeability fracture treatments and certain land-based wells in remote areas where a compact skid is needed. Three significant benefits have resulted from using the compact-skid system: offshore operators have been able to ship the skid system at 20% of shipping costs of non-ISO equipment; on-the-fly mixing has prevented material waste associated with batch-mixing; and volumes pumped on actual jobs have closely matched job designs. Data have been collected from several Gulf of Mexico jobs run with the two-part skid system that has been designed for conducting hydraulic fracture treatments from offshore rigs.

  7. Optimize Deployment of Renewable Energy Technologies for Government Agencies, Industrial Facilities, and Military Installations: NREL Offers Proven Tools and Resources to Reduce Energy Use and Improve Efficiency (Brochure)

    SciTech Connect

    Not Available

    2010-01-01

    The National Renewable Energy Lab provides expertise, facilities, and technical assistance to campuses, facilities, and government agencies to apply renewable energy and energy efficiency technologies.

  8. Highlighting High Performance: The Solar Energy Research Facility, Golden, Colorado

    SciTech Connect

    Torcellini, P.; Epstein, K.

    2001-06-26

    The National Renewable Energy Laboratory's Solar Energy Research Facility in Golden, Colorado, uses a stair-step configuration to allow daylight and heat into the office areas, while the laboratories in the back of the building are in a more controlled environment where tight levels of ventilation, humidity, temperature, and light are critical. A unique mechanical system makes the most of the natural environment and the building's design to efficiently heat and cool the building at an annual utility bill savings of almost $200,000 per year.

  9. High Efficiency, Illumination Quality OLEDs for Lighting

    SciTech Connect

    Joseph Shiang; James Cella; Kelly Chichak; Anil Duggal; Kevin Janora; Chris Heller; Gautam Parthasarathy; Jeffery Youmans; Joseph Shiang

    2008-03-31

    The goal of the program was to demonstrate a 45 lumen per watt white light device based upon the use of multiple emission colors through the use of solution processing. This performance level is a dramatic extension of the team's previous 15 LPW large area illumination device. The fundamental material system was based upon commercial polymer materials. The team was largely able to achieve these goals, and was able to deliver to DOE a 90 lumen illumination source that had an average performance of 34 LPW a 1000 cd/m{sup 2} with peak performances near 40LPW. The average color temperature is 3200K and the calculated CRI 85. The device operated at a brightness of approximately 1000cd/m{sup 2}. The use of multiple emission colors particularly red and blue, provided additional degrees of design flexibility in achieving white light, but also required the use of a multilayered structure to separate the different recombination zones and prevent interconversion of blue emission to red emission. The use of commercial materials had the advantage that improvements by the chemical manufacturers in charge transport efficiency, operating life and material purity could be rapidly incorporated without the expenditure of additional effort. The program was designed to take maximum advantage of the known characteristics of these material and proceeded in seven steps. (1) Identify the most promising materials, (2) assemble them into multi-layer structures to control excitation and transport within the OLED, (3) identify materials development needs that would optimize performance within multilayer structures, (4) build a prototype that demonstrates the potential entitlement of the novel multilayer OLED architecture (5) integrate all of the developments to find the single best materials set to implement the novel multilayer architecture, (6) further optimize the best materials set, (7) make a large area high illumination quality white OLED. A photo of the final deliverable is shown. In

  10. High energy-density science on the National Ignition Facility

    SciTech Connect

    Campbell, E.M.; Cauble, R.; Remington, B.A.

    1997-08-01

    The National Ignition Facility, as well as its French counterpart Le Laser Megajoule, have been designed to confront one of the most difficult and compelling problem in shock physics - the creation of a hot, compassed DT plasma surrounded and confined by cold, nearly degenerate DT fuel. At the same time, these laser facilities will present the shock physics community with unique tools for the study of high energy density matter at states unreachable by any other laboratory technique. Here we describe how these lasers can contribute to investigations of high energy density in the area of material properties and equations of state, extend present laboratory shock techniques such as high-speed jets to new regimes, and allow study of extreme conditions found in astrophysical phenomena.

  11. High-Efficiency Microwave Power Amplifier

    NASA Technical Reports Server (NTRS)

    Sims, Williams H.

    2005-01-01

    A high-efficiency power amplifier that operates in the S band (frequencies of the order of a few gigahertz) utilizes transistors operating under class-D bias and excitation conditions. Class-D operation has been utilized at lower frequencies, but, until now, has not been exploited in the S band. Nominally, in class D operation, a transistor is switched rapidly between "on" and "off" states so that at any given instant, it sustains either high current or high voltage, but not both at the same time. In the ideal case of zero "on" resistance, infinite "off" resistance, zero inductance and capacitance, and perfect switching, the output signal would be a perfect square wave. Relative to the traditional classes A, B, and C of amplifier operation, class D offers the potential to achieve greater power efficiency. In addition, relative to class-A amplifiers, class-D amplifiers are less likely to go into oscillation. In order to design this amplifier, it was necessary to derive mathematical models of microwave power transistors for incorporation into a larger mathematical model for computational simulation of the operation of a class-D microwave amplifier. The design incorporates state-of-the-art switching techniques applicable only in the microwave frequency range. Another major novel feature is a transmission-line power splitter/combiner designed with the help of phasing techniques to enable an approximation of a square-wave signal (which is inherently a wideband signal) to propagate through what would, if designed in a more traditional manner, behave as a more severely band-limited device (see figure). The amplifier includes an input, a driver, and a final stage. Each stage contains a pair of GaAs-based field-effect transistors biased in class D. The input signal can range from -10 to +10 dBm into a 50-ohm load. The table summarizes the performances of the three stages

  12. Novel Nanophosphors for High Efficiency Fluorescent Lamps

    SciTech Connect

    Alok Srivatava

    2007-03-31

    This is the Final Report of the Novel Nanophosphors for High Efficiency Fluorescent Lamps, Department of Energy (DOE). The overall goal of this three-year program is to develop novel hybrid phosphors by coating commercially available lamp phosphors with highly stable wide band-gap nanocrystalline phosphors (NCP). The prime technical approach is the development of NCP quantum-splitting phosphor (QSP) and ultra-violet (UV) emitting phosphors with quantum efficiencies exceeding that of the conventional phosphors at 185 nm. The novel hybrid phosphors will increase the efficiency of the fluorescent lamps by up to 32%, enabling total energy savings of 0.26 quads, the reduction in the U.S. energy bill by $6.5 billion and the reduction of the annual carbon emission by 4.1 billion kilogram. Our work started by investigating through modeling calculations the requirement for the particle size of the NCP. Our work to develop suitable nanocrystalline phosphors started with the known oxide quantum splitting and UV emitting phosphors. We demonstrated several synthesis techniques for the production of high quality nanocrystalline materials that crystallizes in the desired phase and with the desired particle size. In collaboration with our subcontractor we demonstrated the feasibility for the manufacture of NC phosphors. We also demonstrated novel techniques of coating the NCP on the surface of micron sized phosphors. Our chief achievement pertains to the successful testing of the coated hybrid phosphor systems in linear fluorescent lamps. In linear fluorescent lamp tests, we have demonstrated up to 7% increase in the efficacy of hybrid phosphors over the conventional (uncoated) phosphors. We have also demonstrated the improvement in the lumen maintenance of the coated phosphors. A hybrid phosphor system based on the commercial red emitting phosphor, Y{sub 2}O{sub 3}:Eu{sup 3+} did not show the anticipated improvement in lamp efficacy. We explored the reasons for this observation

  13. A Measurement Management Technology for Improving Energy Efficiency in Data Centers and Telecommunication Facilities

    SciTech Connect

    Hendrik Hamann, Levente Klein

    2012-06-28

    Data center (DC) electricity use is increasing at an annual rate of over 20% and presents a concern for the Information Technology (IT) industry, governments, and the society. A large fraction of the energy use is consumed by the compressor cooling to maintain the recommended operating conditions for IT equipment. The most common way to improve the DC efficiency is achieved by optimally provisioning the cooling power to match the global heat dissipation in the DC. However, at a more granular level, the large range of heat densities of today's IT equipment makes the task of provisioning cooling power optimized to the level of individual computer room air conditioning (CRAC) units much more challenging. Distributed sensing within a DC enables the development of new strategies to improve energy efficiency, such as hot spot elimination through targeted cooling, matching power consumption at rack level with workload schedule, and minimizing power losses. The scope of Measurement and Management Technologies (MMT) is to develop a software tool and the underlying sensing technology to provide critical decision support and control for DC and telecommunication facilities (TF) operations. A key aspect of MMT technology is integration of modeling tools to understand how changes in one operational parameter affect the overall DC response. It is demonstrated that reduced ordered models for DC can generate, in less than 2 seconds computational time, a three dimensional thermal model in a 50 kft{sup 2} DC. This rapid modeling enables real time visualization of the DC conditions and enables 'what if' scenarios simulations to characterize response to 'disturbances'. One such example is thermal zone modeling that matches the cooling power to the heat generated at a local level by identifying DC zones cooled by a specific CRAC. Turning off a CRAC unit can be simulated to understand how the other CRAC utilization changes and how server temperature responds. Several new sensing

  14. High efficiency recombineering in lactic acid bacteria

    PubMed Central

    van Pijkeren, Jan-Peter; Britton, Robert A.

    2012-01-01

    The ability to efficiently generate targeted point mutations in the chromosome without the need for antibiotics, or other means of selection, is a powerful strategy for genome engineering. Although oligonucleotide-mediated recombineering (ssDNA recombineering) has been utilized in Escherichia coli for over a decade, the successful adaptation of ssDNA recombineering to Gram-positive bacteria has not been reported. Here we describe the development and application of ssDNA recombineering in lactic acid bacteria. Mutations were incorporated in the chromosome of Lactobacillus reuteri and Lactococcus lactis without selection at frequencies ranging between 0.4% and 19%. Whole genome sequence analysis showed that ssDNA recombineering is specific and not hypermutagenic. To highlight the utility of ssDNA recombineering we reduced the intrinsic vancomymycin resistance of L. reuteri >100-fold. By creating a single amino acid change in the d-Ala-d-Ala ligase enzyme we reduced the minimum inhibitory concentration for vancomycin from >256 to 1.5 µg/ml, well below the clinically relevant minimum inhibitory concentration. Recombineering thus allows high efficiency mutagenesis in lactobacilli and lactococci, and may be used to further enhance beneficial properties and safety of strains used in medicine and industry. We expect that this work will serve as a blueprint for the adaptation of ssDNA recombineering to other Gram-positive bacteria. PMID:22328729

  15. Tips for selecting highly efficient cyclones

    SciTech Connect

    Amrein, D.L.

    1995-05-01

    Cyclone dust collectors have been used--and misused--all over the world for more than 100 years. One reason for the misuse is a common perception among users that all cyclones are created equal--that is, as long as a cyclone resembles a cylinder with an attached cone, it will do its job. However, to maximize separation efficiency in a specific application requires a precise cyclone design, engineered to exact fit many possible variables. A well-designed cyclone, for instance, can achieve efficiencies as high s 99.9+% when operated properly within the envelope of its specifications. Nonetheless, cyclones are often used only as first-stage filters for performing crude separations, with final collections being carried out by more-costly baghouses and scrubbers. Compared with baghouses and scrubbers, cyclones have two important considerations in their favor. One, they are almost invariably safer--in terms of the potential for generating fires and explosions--than fabric filters. Second, cyclones have lower maintenance costs since there are no filter media to replace. The paper discusses the operation, design, and troubleshooting of cyclones.

  16. Highly Efficient Vector-Inversion Pulse Generators

    NASA Technical Reports Server (NTRS)

    Rose, Franklin

    2004-01-01

    Improved transmission-line pulse generators of the vector-inversion type are being developed as lightweight sources of pulsed high voltage for diverse applications, including spacecraft thrusters, portable x-ray imaging systems, impulse radar systems, and corona-discharge systems for sterilizing gases. In this development, more than the customary attention is paid to principles of operation and details of construction so as to the maximize the efficiency of the pulse-generation process while minimizing the sizes of components. An important element of this approach is segmenting a pulse generator in such a manner that the electric field in each segment is always below the threshold for electrical breakdown. One design of particular interest, a complete description of which was not available at the time of writing this article, involves two parallel-plate transmission lines that are wound on a mandrel, share a common conductor, and are switched in such a manner that the pulse generator is divided into a "fast" and a "slow" section. A major innovation in this design is the addition of ferrite to the "slow" section to reduce the size of the mandrel needed for a given efficiency.

  17. High efficiency francium trap for precision spectroscopy

    NASA Astrophysics Data System (ADS)

    Aubin, Seth Andre Morgan

    We cooled and trapped francium in a high efficiency magneto-optical trap. The francium is produced artificially in a nuclear fusion reaction using the Stony Brook superconducting LINAC. We observed an average trap population of 50,000 210Fr, corresponding to a trapping efficiency of 1.2%. The trapped atoms are cooled to a temperature of 75 muK. We used the new trapping apparatus for spectroscopic studies of the 9S 1/2 level of 210Fr to test the precision of atomic theory. We measured the hyperfine splitting of the 9S1/2 level, and with time-correlated single photon counting, we measured its radiative lifetime. We found a lifetime of 107.53 +/- 0.80 ns and a hyperfine splitting of 4045.1 +/- 1.1 MHz. We characterized the optical properties of a dipole trap based on an axicon lens to provide a low perturbation environment for precision spectroscopy. The axicon generates a region of darkness surrounded by light. For blue-detuned light, cold atoms are trapped in the dark region and experience almost no perturbing fields. This work continues the spectroscopic studies of francium for tests of atomic theory and opens the way for nuclear anapole moment measurements.

  18. Demonstration of Color Separation with 2ω KDP Wedge in High Power Laser Facilities

    NASA Astrophysics Data System (ADS)

    Wang, Fang; Li, Fu-Quan; Han, Wei; Feng, Bin; Zhou, Li-Dan; Jia, Huai-Ting; Cao, Hua-Bao

    2014-01-01

    A 2ω wedge design is proposed with KDP crystal to disperse the unconverted light away from the target in a high power laser facility for inertial confinement fusion. The ultraviolet B-integral problem is released, and about 1.2 times in color separation angle is achieved according to both theoretical and experimental investigations when compared with conventional 3ω wedge. The frequency conversion efficiency is unaffected when the wedge is along the non-sensitive axis of the tripler.

  19. High efficiency Brayton cycles using LNG

    DOEpatents

    Morrow, Charles W.

    2006-04-18

    A modified, closed-loop Brayton cycle power conversion system that uses liquefied natural gas as the cold heat sink media. When combined with a helium gas cooled nuclear reactor, achievable efficiency can approach 68 76% (as compared to 35% for conventional steam cycle power cooled by air or water). A superheater heat exchanger can be used to exchange heat from a side-stream of hot helium gas split-off from the primary helium coolant loop to post-heat vaporized natural gas exiting from low and high-pressure coolers. The superheater raises the exit temperature of the natural gas to close to room temperature, which makes the gas more attractive to sell on the open market. An additional benefit is significantly reduced costs of a LNG revaporization plant, since the nuclear reactor provides the heat for vaporization instead of burning a portion of the LNG to provide the heat.

  20. High power, high efficiency diode pumped Raman fiber laser

    NASA Astrophysics Data System (ADS)

    Glick, Yaakov; Fromzel, Viktor; Zhang, Jun; Dahan, Asaf; Ter-Gabrielyan, Nikolay; Pattnaik, Radha K.; Dubinskii, Mark

    2016-06-01

    We demonstrate a high power high efficiency Raman fiber laser pumped directly by a laser diode module at 976 nm. 80 Watts of CW power were obtained at a wavelength of 1020 nm with an optical-to-optical efficiency of 53%. When working quasi-CW, at a duty cycle of 30%, 85 W of peak power was produced with an efficiency of 60%. A commercial graded-index (GRIN) core fiber acts as the Raman fiber in a power oscillator configuration, which includes spectral selection to prevent generation of the 2nd Stokes. In addition, significant brightness enhancement of the pump beam is attained due to the Raman gain distribution profile in the GRIN fiber. To the best of our knowledge, this is the highest power Raman fiber laser directly pumped by laser diodes, which also exhibits a record efficiency for such a laser. In addition, it is the highest power Raman fiber laser (regardless of pumping source) demonstrated based on a GRIN fiber.

  1. A high-efficiency superhydrophobic plasma separator.

    PubMed

    Liu, Changchun; Liao, Shih-Chuan; Song, Jinzhao; Mauk, Michael G; Li, Xuanwen; Wu, Gaoxiang; Ge, Dengteng; Greenberg, Robert M; Yang, Shu; Bau, Haim H

    2016-02-01

    To meet stringent limit-of-detection specifications for low abundance target molecules, a relatively large volume of plasma is needed for many blood-based clinical diagnostics. Conventional centrifugation methods for plasma separation are not suitable for on-site testing or bedside diagnostics. Here, we report a simple, yet high-efficiency, clamshell-style, superhydrophobic plasma separator that is capable of separating a relatively large volume of plasma from several hundred microliters of whole blood (finger-prick blood volume). The plasma separator consists of a superhydrophobic top cover with a separation membrane and a superhydrophobic bottom substrate. Unlike previously reported membrane-based plasma separators, the separation membrane in our device is positioned at the top of the sandwiched whole blood film to increase the membrane separation capacity and plasma yield. In addition, the device's superhydrophobic characteristics (i) facilitates the formation of well-defined, contracted, thin blood film with a high contact angle; (ii) minimizes biomolecular adhesion to surfaces; (iii) increases blood clotting time; and (iv) reduces blood cell hemolysis. The device demonstrated a "blood in-plasma out" capability, consistently extracting 65 ± 21.5 μL of plasma from 200 μL of whole blood in less than 10 min without electrical power. The device was used to separate plasma from Schistosoma mansoni genomic DNA-spiked whole blood with a recovery efficiency of >84.5 ± 25.8%. The S. mansoni genomic DNA in the separated plasma was successfully tested on our custom-made microfluidic chip by using loop mediated isothermal amplification (LAMP) method.

  2. A High-Efficiency Superhydrophobic Plasma Separator

    PubMed Central

    Liu, Changchun; Liao, Shih-Chuan; Song, Jinzhao; Mauk, Michael G.; Li, Xuanwen; Wu, Gaoxiang; Ge, Dengteng; Greenberg, Robert M.; Yang, Shu; Bau, Haim H.

    2016-01-01

    To meet stringent limit-of-detection specifications for low abundance target molecules, a relatively large volume of plasma is needed for many blood-based clinical diagnostics. Conventional centrifugation methods for plasma separation are not suitable for on-site testing or bedside diagnostics. Here, we report a simple, yet high-efficiency, clamshell-style, superhydrophobic plasma separator that is capable of separating a relatively large volume of plasma from several hundred microliters of whole blood (finger-prick blood volume). The plasma separator consists of a superhydrophobic top cover with a separation membrane and a superhydrophobic bottom substrate. Unlike previously reported membrane-based plasma separators, the separation membrane in our device is positioned at the top of the sandwiched whole blood film to increase the membrane separation capacity and plasma yield. In addition, the device’s superhydrophobic characteristics (i) facilitates the formation of well-defined, contracted, thin blood film with a high contact angle; (ii) minimizes biomolecular adhesion to surfaces; (iii) increases blood clotting time; and (iv) reduces blood cell hemolysis. The device demonstrated a “blood in-plasma out” capability, consistently extracting 65±21.5 μL of plasma from 200 μL of whole blood in less than 10 min without electrical power. The device was used to separate plasma from Schistosoma mansoni genomic DNA-spiked whole blood with a recovery efficiency of > 84.5 ± 25.8 %. The S. mansoni genomic DNA in the separated plasma was successfully tested on our custom-made microfluidic chip by using loop mediated isothermal amplification (LAMP) method. PMID:26732765

  3. Novel High Efficient Organic Photovoltaic Materials

    NASA Technical Reports Server (NTRS)

    Sun, Sam; Haliburton, James; Wang, Yi-Qing; Fan, Zhen; Taft, Charles; Maaref, Shahin; Bailey, Sheila (Technical Monitor)

    2003-01-01

    Solar energy is a renewable, nonpolluting, and most abundant energy source for human exploration of a remote site or outer space. In order to generate appreciable electrical power in space or on the earth, it is necessary to collect sunlight from large areas and with high efficiency due to the low density of sunlight. Future organic or polymer (plastic) solar cells appear very attractive due to their unique features such as light weight, flexible shape, tunability of energy band-gaps via versatile molecular or supramolecular design, synthesis, processing and device fabrication schemes, and much lower cost on large scale industrial production. It has been predicted that supramolecular and nano-phase separated block copolymer systems containing electron rich donor blocks and electron deficient acceptor blocks may facilitate the charge carrier separation and migration due to improved electronic ultrastructure and morphology in comparison to polymer composite system. This presentation will describe our recent progress in the design, synthesis and characterization of a novel block copolymer system containing donor and acceptor blocks covalently attached. Specifically, the donor block contains an electron donating alkyloxy derivatized polyphenylenevinylene (RO-PPV), the acceptor block contains an electron withdrawing alkyl-sulfone derivatized polyphenylenevinylene (SF-PPV). The key synthetic strategy includes the synthesis of each individual block first, then couple the blocks together. While the donor block has a strong PL emission at around 560 nm, and acceptor block has a strong PL emission at around 520 nm, the PL emissions of final block copolymers are severely quenched. This verifies the expected electron transfer and charge separation due to interfaces of donor and acceptor nano phase separated blocks. The system therefore has potential for variety light harvesting applications, including high efficient photovoltaic applications.

  4. A high-efficiency superhydrophobic plasma separator.

    PubMed

    Liu, Changchun; Liao, Shih-Chuan; Song, Jinzhao; Mauk, Michael G; Li, Xuanwen; Wu, Gaoxiang; Ge, Dengteng; Greenberg, Robert M; Yang, Shu; Bau, Haim H

    2016-02-01

    To meet stringent limit-of-detection specifications for low abundance target molecules, a relatively large volume of plasma is needed for many blood-based clinical diagnostics. Conventional centrifugation methods for plasma separation are not suitable for on-site testing or bedside diagnostics. Here, we report a simple, yet high-efficiency, clamshell-style, superhydrophobic plasma separator that is capable of separating a relatively large volume of plasma from several hundred microliters of whole blood (finger-prick blood volume). The plasma separator consists of a superhydrophobic top cover with a separation membrane and a superhydrophobic bottom substrate. Unlike previously reported membrane-based plasma separators, the separation membrane in our device is positioned at the top of the sandwiched whole blood film to increase the membrane separation capacity and plasma yield. In addition, the device's superhydrophobic characteristics (i) facilitates the formation of well-defined, contracted, thin blood film with a high contact angle; (ii) minimizes biomolecular adhesion to surfaces; (iii) increases blood clotting time; and (iv) reduces blood cell hemolysis. The device demonstrated a "blood in-plasma out" capability, consistently extracting 65 ± 21.5 μL of plasma from 200 μL of whole blood in less than 10 min without electrical power. The device was used to separate plasma from Schistosoma mansoni genomic DNA-spiked whole blood with a recovery efficiency of >84.5 ± 25.8%. The S. mansoni genomic DNA in the separated plasma was successfully tested on our custom-made microfluidic chip by using loop mediated isothermal amplification (LAMP) method. PMID:26732765

  5. Facile Preparation of Nanostructured, Superhydrophobic Filter Paper for Efficient Water/Oil Separation.

    PubMed

    Wang, Jianhua; Wong, Jessica X H; Kwok, Honoria; Li, Xiaochun; Yu, Hua-Zhong

    2016-01-01

    In this paper, we present a facile and cost-effective method to obtain superhydrophobic filter paper and demonstrate its application for efficient water/oil separation. By coupling structurally distinct organosilane precursors (e.g., octadecyltrichlorosilane and methyltrichlorosilane) to paper fibers under controlled reaction conditions, we have formulated a simple, inexpensive, and efficient protocol to achieve a desirable superhydrophobic and superoleophilic surface on conventional filter paper. The silanized superhydrophobic filter paper showed nanostructured morphology and demonstrated great separation efficiency (up to 99.4%) for water/oil mixtures. The modified filter paper is stable in both aqueous solutions and organic solvents, and can be reused multiple times. The present study shows that our newly developed binary silanization is a promising method of modifying cellulose-based materials for practical applications, in particular the treatment of industrial waste water and ecosystem recovery. PMID:26982055

  6. Facile Preparation of Nanostructured, Superhydrophobic Filter Paper for Efficient Water/Oil Separation.

    PubMed

    Wang, Jianhua; Wong, Jessica X H; Kwok, Honoria; Li, Xiaochun; Yu, Hua-Zhong

    2016-01-01

    In this paper, we present a facile and cost-effective method to obtain superhydrophobic filter paper and demonstrate its application for efficient water/oil separation. By coupling structurally distinct organosilane precursors (e.g., octadecyltrichlorosilane and methyltrichlorosilane) to paper fibers under controlled reaction conditions, we have formulated a simple, inexpensive, and efficient protocol to achieve a desirable superhydrophobic and superoleophilic surface on conventional filter paper. The silanized superhydrophobic filter paper showed nanostructured morphology and demonstrated great separation efficiency (up to 99.4%) for water/oil mixtures. The modified filter paper is stable in both aqueous solutions and organic solvents, and can be reused multiple times. The present study shows that our newly developed binary silanization is a promising method of modifying cellulose-based materials for practical applications, in particular the treatment of industrial waste water and ecosystem recovery.

  7. Facile Preparation of Nanostructured, Superhydrophobic Filter Paper for Efficient Water/Oil Separation

    PubMed Central

    Wang, Jianhua; Wong, Jessica X. H.; Kwok, Honoria; Li, Xiaochun; Yu, Hua-Zhong

    2016-01-01

    In this paper, we present a facile and cost-effective method to obtain superhydrophobic filter paper and demonstrate its application for efficient water/oil separation. By coupling structurally distinct organosilane precursors (e.g., octadecyltrichlorosilane and methyltrichlorosilane) to paper fibers under controlled reaction conditions, we have formulated a simple, inexpensive, and efficient protocol to achieve a desirable superhydrophobic and superoleophilic surface on conventional filter paper. The silanized superhydrophobic filter paper showed nanostructured morphology and demonstrated great separation efficiency (up to 99.4%) for water/oil mixtures. The modified filter paper is stable in both aqueous solutions and organic solvents, and can be reused multiple times. The present study shows that our newly developed binary silanization is a promising method of modifying cellulose-based materials for practical applications, in particular the treatment of industrial waste water and ecosystem recovery. PMID:26982055

  8. The entire beam wavefront control of high power laser facility

    NASA Astrophysics Data System (ADS)

    Dai, Wanjun; Wang, Deen; Hu, Dongxia; Zhang, Xin; Zhou, Wei; Yuan, Qiang; Deng, Xuewei; Wang, Yuancheng; Deng, Wu; Yang, Ying; Zhu, Qihua; Jing, Feng

    2015-02-01

    Experiment of entire beam wavefront compensation was carried out in a beamline of a high power laser facility, and two adaptive optics systems with different intentions were applied in the chosen beamline. After correction, the far-filed irradiance distribution is concentrated evidently and the entrance rate of 3ω focal spot to a 500-μm hole is improved to be about 95% under number kilojoules energy.

  9. High Energy Density Physics on LULI2000 Laser Facility

    NASA Astrophysics Data System (ADS)

    Koenig, M.; Benuzzi-Mounaix, A.; Ozaki, N.; Ravasio, A.; Vinci, T.; Lepape, S.; Tanaka, K.; Riley, D.

    2006-07-01

    We present here a summary of some High Density Energy Physics experiments performed on the new facility LULI 2000. First, different flyer plate targets scheme have been tested loading shock in fused-quartz plate. Temperature data along the Hugoniot curve have been obtained. Second, a strongly coupled and degenerated Aluminium plasma has been probed by X-ray Thomson scattering. Compton shift from electrons has been observed in various density conditions.

  10. High-temperature acoustic test facilities and methods

    NASA Astrophysics Data System (ADS)

    Pearson, Jerome

    1994-09-01

    The Wright Laboratory is the Air Force center for air vehicles, responsible for developing advanced technology and incorporating it into new flight vehicles and for continuous technological improvement of operational air vehicles. Part of that responsibility is the problem of acoustic fatigue. With the advent of jet aircraft in the 1950's, acoustic fatigue of aircraft structure became a significant problem. In the 1960's the Wright Laboratory constructed the first large acoustic fatigue test facilities in the United States, and the laboratory has been a dominant factor in high-intensity acoustic testing since that time. This paper discusses some of the intense environments encountered by new and planned Air Force flight vehicles, and describes three new acoustic test facilities of the Wright Laboratory designed for testing structures in these dynamic environments. These new test facilities represent the state of the art in high-temperature, high-intensity acoustic testing and random fatigue testing. They will allow the laboratory scientists and engineers to test the new structures and materials required to withstand the severe environments of captive-carry missiles, augmented lift wings and flaps, exhaust structures of stealth aircraft, and hypersonic vehicle structures well into the twenty-first century.

  11. White LED with High Package Extraction Efficiency

    SciTech Connect

    Yi Zheng; Matthew Stough

    2008-09-30

    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

  12. Tailored Materials for High Efficiency CIDI Engines

    SciTech Connect

    Grant, G.J.; Jana, S.

    2012-03-30

    The overall goal of the project, Tailored Materials for High Efficiency Compression Ignition Direct Injection (CIDI) Engines, is to enable the implementation of new combustion strategies, such as homogeneous charge compression ignition (HCCI), that have the potential to significantly increase the energy efficiency of current diesel engines and decrease fuel consumption and environmental emissions. These strategies, however, are increasing the demands on conventional engine materials, either from increases in peak cylinder pressure (PCP) or from increases in the temperature of operation. The specific objective of this project is to investigate the application of a new material processing technology, friction stir processing (FSP), to improve the thermal and mechanical properties of engine components. The concept is to modify the surfaces of conventional, low-cost engine materials. The project focused primarily on FSP in aluminum materials that are compositional analogs to the typical piston and head alloys seen in small- to mid-sized CIDI engines. Investigations have been primarily of two types over the duration of this project: (1) FSP of a cast hypoeutectic Al-Si-Mg (A356/357) alloy with no introduction of any new components, and (2) FSP of Al-Cu-Ni alloys (Alloy 339) by physically stirring-in various quantities of carbon nanotubes/nanofibers or carbon fibers. Experimental work to date on aluminum systems has shown significant increases in fatigue lifetime and stress-level performance in aluminum-silicon alloys using friction processing alone, but work to demonstrate the addition of carbon nanotubes and fibers into aluminum substrates has shown mixed results due primarily to the difficulty in achieving porosity-free, homogeneous distributions of the particulate. A limited effort to understand the effects of FSP on steel materials was also undertaken during the course of this project. Processed regions were created in high-strength, low-alloyed steels up to 0.5 in

  13. Solvent extraction studies with high-burnup Fast Flux Test Facility fuel in the Solvent Extraction Test Facility

    SciTech Connect

    Benker, D.E.; Bigelow, J.E.; Bond, W.D.; Chattin, F.R.; King, L.J.; Kitts, F.G.; Ross, R.G.; Stacy, R.G.

    1986-10-01

    A batch of high-burnup fuel from the Fast Flux Test Facility (FFTF) was processed in the Solvent Extraction Test Facility (SETF) during Campaign 9. The fuel had a burnup of {similar_to}0 MWd/kg and a cooling time of {similar_to} year. Two runs were made with this fuel; in the first, the solvent contained 30% tri-n-butyl phosphate (TBP) and partitioning of the uranium and plutonium was effected by reducing the plutonium with hydroxylamine nitrate (HAN); in the second, the solvent contained 10% TBP and a low operating temperature was used in an attempt to partition without reducing the plutonium valence. The plutonium reoxidation problem, which was present in previous runs that used HAN, may have been solved by lowering the temperature and acidity in the partition contactor. An automatic control system was used to maintain high loadings of heavy metals in the coextraction-coscrub contactor in order to increase its efficiency while maintaining low losses of uranium and plutonium to the aqueous raffinate. An in-line photometer system was used to measure the plutonium concentration in an intermediate extraction stage; and based on this data, a computer algorithm determined the appropriate adjustments in the addition rate of the extractant. The control system was successfully demonstrated in a preliminary run with purified uranium. However, a variety of equipment and start up problems prevented an extended demonstration from being accomplished during the runs with the FFTF fuel.

  14. High Purity Germanium Gamma-PHA Assay of Uranium Scrap Cans Used in 321-M Facility

    NASA Astrophysics Data System (ADS)

    Salaymeh, S. R.; Dewberry, R. A.; Casella, V.

    2001-12-01

    The Analytical Development Section of SRTC was requested by the Facilities Disposition Division (FDD) to determine the holdup of enriched uranium in the 321-M facility as part of an overall deactivation project of the facility. The 321-M facility was used to fabricate enriched uranium fuel assemblies, lithium-aluminum target tubes, neptunium assemblies, and miscellaneous components for the production reactors. The facility also includes the 324-M storage building and the passageway connecting it to 321-M. The results of the holdup assays are essential for determining compliance with the Solid Waste's Waste Acceptance Criteria, Material Control & Accountability, and to meet criticality safety controls. This report describes and documents the use of a portable HPGe detector and EG&G DART system that contains a high voltage power supply, signal processing electronics, a personal computer with Gamma-Vision software, and space to store and manipulate multiple 4096-channel gamma-ray spectra to assay for 235U content. The system was used to assay a large number of scrap cans used to store highly enriched uranium (HEU) chips and filings. This report includes a description of two efficiency calibration configurations and also the results of the assay. A description of the quality control checks is included as well.

  15. High efficient ZnO nanowalnuts photocatalyst: A case study

    SciTech Connect

    Yan, Feng; Zhang, Siwen; Liu, Yang; Liu, Hongfeng; Qu, Fengyu; Cai, Xue; Wu, Xiang

    2014-11-15

    Highlights: • Walnut-like ZnO nanostructures are synthesized through a facile hydrothermal method. • Morphologies and microstructures of the as-obtained ZnO products were investigated. • The photocatalytic results demonstrate that methyl orange (MO) aqueous solution can be degraded over 97% after 45 min under UV light irradiation. - Abstract: Walnut-like ZnO nanostructures are successfully synthesized through a facile hydrothermal method. The structure and morphology of the as-synthesized products were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The photocatalytic properties of ZnO nanowalnuts are investigated by photodegradating several organic dyes, such as Congo red (CR), methyl orange (MO) and eosin red aqueous solutions under UV irradiation, respectively. The results demonstrate that methyl orange (MO) aqueous solution can be degraded over 97% after 45 min under UV light irradiation. In addition, eosin red and Congo red (CR) aqueous solution degradation experiments are also conducted in the same condition, respectively. It showed that ZnO nanowalnuts represent high photocatalytic activities with a degradation efficiency of 87% for CR with 115 min of irradiation and 97% for eosin red with 55 min of irradiation. The reported ZnO products may be promising candidates as the photocatalysts in waste water treatment.

  16. Facile Preparation of Molybdenum Bronzes as an Efficient Hole Extraction Layer in Organic Photovoltaics.

    PubMed

    Wang, Jiantai; Zhang, Jun; Meng, Bin; Zhang, Baohua; Xie, Zhiyuan; Wang, Lixiang

    2015-06-24

    We proposed a facile and green one-pot strategy to synthesize Mo bronzes nanoparticles to serve as an efficient hole extraction layer in polymer solar cells. Mo bronzes were obtained through reducing the fractional self-aggregated ammonium heptamolybdate with appropriate reducing agent ascorbic acid, and its optoelectronic properties were fully characterized. The synthesized Mo bronzes displayed strong n-type semiconductor characteristics with a work function of 5.2-5.4 eV, matched well with the energy levels of current donor polymers. The presented gap states of the Mo bronzes near the Fermi level were beneficial for facilitating charge extraction. The as-synthesized Mo bronzes were used as hole extraction layer in polymer solar cells and significantly enhanced the photovoltaic performance and stability. The power conversion efficiency was increased by more than 18% compared with the polyethylene dioxythiophene:polystyrenesulfonate-based reference cell. The excellent performance and facile preparation render the as-synthesized solution-processed Mo bronzes nanoparticles a promising candidate for hole extraction layer in low-cost and efficient polymer solar cells.

  17. Conceptual definition of a high voltage power supply test facility

    NASA Technical Reports Server (NTRS)

    Biess, John J.; Chu, Teh-Ming; Stevens, N. John

    1989-01-01

    NASA Lewis Research Center is presently developing a 60 GHz traveling wave tube for satellite cross-link communications. The operating voltage for this new tube is - 20 kV. There is concern about the high voltage insulation system and NASA is planning a space station high voltage experiment that will demonstrate both the 60 GHz communications and high voltage electronics technology. The experiment interfaces, requirements, conceptual design, technology issues and safety issues are determined. A block diagram of the high voltage power supply test facility was generated. It includes the high voltage power supply, the 60 GHz traveling wave tube, the communications package, the antenna package, a high voltage diagnostics package and a command and data processor system. The interfaces with the space station and the attached payload accommodations equipment were determined. A brief description of the different subsystems and a discussion of the technology development needs are presented.

  18. Novel High Efficient Organic Photovoltaic Materials

    NASA Technical Reports Server (NTRS)

    Sun, Sam; Haliburton, James; Fan, Zben; Taft, Charles; Wang, Yi-Qing; Maaref, Shahin; Mackey, Willie R. (Technical Monitor)

    2001-01-01

    In man's mission to the outer space or a remote site, the most abundant, renewable, nonpolluting, and unlimited external energy source is light. Photovoltaic (PV) materials can convert light into electrical power. In order to generate appreciable electrical power in space or on the Earth, it is necessary to collect sunlight from large areas due to the low density of sunlight, and this would be very costly using current commercially available inorganic solar cells. Future organic or polymer based solar cells seemed very attractive due to several reasons. These include lightweight, flexible shape, ultra-fast optoelectronic response time (this also makes organic PV materials attractive for developing ultra-fast photo detectors), tunability of energy band-gaps via molecular design, versatile materials synthesis and device fabrication schemes, and much lower cost on large-scale industrial production. It has been predicted that nano-phase separated block copolymer systems containing electron rich donor blocks and electron deficient acceptor blocks will facilitate the charge separation and migration due to improved electronic ultrastructure and morphology in comparison to current polymer composite photovoltaic system. This presentation will describe our recent progress in the design, synthesis and characterization of a novel donor-bridge-acceptor block copolymer system for potential high-efficient organic optoelectronic applications. Specifically, the donor block contains an electron donating alkyloxy derivatized polyphenylenevinylene, the acceptor block contains an electron withdrawing alkyl-sulfone derivatized polyphenylenevinylene, and the bridge block contains an electronically neutral non-conjugated aliphatic hydrocarbon chain. The key synthetic strategy includes the synthesis of each individual block first, then couple the blocks together. While the donor block stabilizes the holes, the acceptor block stabilizes the electrons. The bridge block is designed to hinder

  19. Broad-beam, high current, metal ion implantation facility

    SciTech Connect

    Brown, I.G.; Dickinson, M.R.; Galvin, J.E.; Godechot, X.; MacGill, R.A.

    1990-07-01

    We have developed a high current metal ion implantation facility with which high current beams of virtually all the solid metals of the Periodic Table can be produced. The facility makes use of a metal vapor vacuum arc ion source which is operated in a pulsed mode, with pulse width 0.25 ms and repetition rate up to 100 pps. Beam extraction voltage is up to 100 kV, corresponding to an ion energy of up to several hundred keV because of the ion charge state multiplicity; beam current is up to several Amperes peak and around 10 mA time averaged delivered onto target. Implantation is done in a broad-beam mode, with a direct line-of-sight from ion source to target. Here we describe the facility and some of the implants that have been carried out using it, including the seeding' of silicon wafers prior to CVD with titanium, palladium or tungsten, the formation of buried iridium silicide layers, and actinide (uranium and thorium) doping of III-V compounds. 16 refs., 6 figs.

  20. Basic studies of 3-V high efficiency cell components

    NASA Astrophysics Data System (ADS)

    Lundstrom, M. S.; Melloch, M. R.; Pierret, R. F.; Carpenter, M. S.; Chuang, H. L.; Keshavarzi, A.; Klausmeier-Brown, M. E.; Lush, G. B.; Morgan, J. M.; Stellwag, T. B.

    1990-07-01

    This project's objective is to improve our fundamental understanding of the generation, recombination, and transport of carriers within III-V homo- and heterostructures. The research consists of fabricating and characterizing solar cell building blocks such as junctions and heterojunctions as well as basic measurements of material parameters. A significant effort is also being directed at characterizing loss mechanisms in high-quality, III-V solar cells fabricated in industrial research laboratories throughout the United States. The project's goal is to use our understanding of the device physics of high-efficiency cell components to maximize cell efficiency. A related goal is the demonstration of new cell structures fabricated by molecular beam epitaxy (MBE). The development of measurement techniques and characterization methodologies is also a project objective. We expect that the insight into III-V device physics occurring during the course of this work will help to identify paths toward higher efficiency III-V cells. This report describes our progress during the fourth year of the project. The past year's efforts centered on completing studies of heavy doping effects in p(sup +)-GaAs and assessing the importance of similar effects in n(sup +)-GaAs, and at continuing research on characterizing, controlling, and passivating perimeter recombination currents. We also initiated work to identify the dominant loss mechanism in Al(sub 0.2)Ga(sub 0.8) As solar cells and brought on-line a new MBE growth facility and demonstrated the high-quality of the films by fabricating, with assistance from Spire Corporation, 23.8 percent 1-sun solar cells.

  1. Sandia National Laboratories' new high level acoustic test facility

    SciTech Connect

    Rogers, J. D.; Hendrick, D. M.

    1989-01-01

    A high intensity acoustic test facility has been designed and is under construction at Sandia National Laboratories in Albuquerque, NM. The chamber is designed to provide an acoustic environment of 154dB (re 20 {mu}Pa) overall sound pressure level over the bandwidth of 50 Hz to 10,000 Hz. The chamber has a volume of 16,000 cubic feet with interior dimensions of 21.6 ft {times} 24.6 ft {times} 30 ft. The construction of the chamber should be complete by the summer of 1990. This paper discusses the design goals and constraints of the facility. The construction characteristics are discussed in detail, as are the acoustic performance design characteristics. The authors hope that this work will help others in designing acoustic chambers. 12 refs., 6 figs.

  2. A high-efficiency aerothermoelastic analysis method

    NASA Astrophysics Data System (ADS)

    Wan, ZhiQiang; Wang, YaoKun; Liu, YunZhen; Yang, Chao

    2014-06-01

    In this paper, a high-efficiency aerothermoelastic analysis method based on unified hypersonic lifting surface theory is established. The method adopts a two-way coupling form that couples the structure, aerodynamic force, and aerodynamic thermo and heat conduction. The aerodynamic force is first calculated based on unified hypersonic lifting surface theory, and then the Eckert reference temperature method is used to solve the temperature field, where the transient heat conduction is solved using Fourier's law, and the modal method is used for the aeroelastic correction. Finally, flutter is analyzed based on the p-k method. The aerothermoelastic behavior of a typical hypersonic low-aspect ratio wing is then analyzed, and the results indicate the following: (1) the combined effects of the aerodynamic load and thermal load both deform the wing, which would increase if the flexibility, size, and flight time of the hypersonic aircraft increase; (2) the effect of heat accumulation should be noted, and therefore, the trajectory parameters should be considered in the design of hypersonic flight vehicles to avoid hazardous conditions, such as flutter.

  3. Highly Efficient Contactless Electrical Energy Transmission System

    NASA Astrophysics Data System (ADS)

    Ayano, Hideki; Nagase, Hiroshi; Inaba, Hiromi

    This paper proposes a new concept for a contactless electrical energy transmission system for an elevator and an automated guided vehicle. The system has rechargeable batteries on the car and electrical energy is supplied at a specific place. When electric power is supplied to the car, it runs automatically and approaches the battery charger. Therefore, a comparatively large gap is needed between the primary transformer at the battery charger and the secondary transformer on the car in order to prevent damage which would be caused by a collision. In this case, a drop of the transformer coupling rate due to the large gap must be prevented. In conventional contactless electrical energy transmission technology, since electric power is received by a pick-up coil from a power line, a large-sized transformer is required. And when the distance over which the car runs is long, the copper loss of the line also increases. The developed system adopts a high frequency inverter using a soft switching method to miniaturize the transformer. The system has a coupling rate of 0.88 for a transformer gap length of 10mm and can operate at 91% efficiency.

  4. Multi-petascale highly efficient parallel supercomputer

    DOEpatents

    Asaad, Sameh; Bellofatto, Ralph E.; Blocksome, Michael A.; Blumrich, Matthias A.; Boyle, Peter; Brunheroto, Jose R.; Chen, Dong; Cher, Chen -Yong; Chiu, George L.; Christ, Norman; Coteus, Paul W.; Davis, Kristan D.; Dozsa, Gabor J.; Eichenberger, Alexandre E.; Eisley, Noel A.; Ellavsky, Matthew R.; Evans, Kahn C.; Fleischer, Bruce M.; Fox, Thomas W.; Gara, Alan; Giampapa, Mark E.; Gooding, Thomas M.; Gschwind, Michael K.; Gunnels, John A.; Hall, Shawn A.; Haring, Rudolf A.; Heidelberger, Philip; Inglett, Todd A.; Knudson, Brant L.; Kopcsay, Gerard V.; Kumar, Sameer; Mamidala, Amith R.; Marcella, James A.; Megerian, Mark G.; Miller, Douglas R.; Miller, Samuel J.; Muff, Adam J.; Mundy, Michael B.; O'Brien, John K.; O'Brien, Kathryn M.; Ohmacht, Martin; Parker, Jeffrey J.; Poole, Ruth J.; Ratterman, Joseph D.; Salapura, Valentina; Satterfield, David L.; Senger, Robert M.; Smith, Brian; Steinmacher-Burow, Burkhard; Stockdell, William M.; Stunkel, Craig B.; Sugavanam, Krishnan; Sugawara, Yutaka; Takken, Todd E.; Trager, Barry M.; Van Oosten, James L.; Wait, Charles D.; Walkup, Robert E.; Watson, Alfred T.; Wisniewski, Robert W.; Wu, Peng

    2015-07-14

    A Multi-Petascale Highly Efficient Parallel Supercomputer of 100 petaOPS-scale computing, at decreased cost, power and footprint, and that allows for a maximum packaging density of processing nodes from an interconnect point of view. The Supercomputer exploits technological advances in VLSI that enables a computing model where many processors can be integrated into a single Application Specific Integrated Circuit (ASIC). Each ASIC computing node comprises a system-on-chip ASIC utilizing four or more processors integrated into one die, with each having full access to all system resources and enabling adaptive partitioning of the processors to functions such as compute or messaging I/O on an application by application basis, and preferably, enable adaptive partitioning of functions in accordance with various algorithmic phases within an application, or if I/O or other processors are underutilized, then can participate in computation or communication nodes are interconnected by a five dimensional torus network with DMA that optimally maximize the throughput of packet communications between nodes and minimize latency.

  5. High efficiency transformation of E. coli by high voltage electroporation.

    PubMed

    Dower, W J; Miller, J F; Ragsdale, C W

    1988-07-11

    E. coli can be transformed to extremely high efficiencies by subjecting a mixture of cells and DNA to brief but intense electrical fields of exponential decay waveform (electroporation). We have obtained 10(9) to 10(10) transformants/micrograms with strains LE392 and DH5 alpha, and plasmids pUC18 and pBR329. The process is highly dependent on two characteristics of the electrical pulse: the electric field strength and the pulse length (RC time constant). The frequency of transformation is a linear function of the DNA concentration over at least six orders of magnitude; and the efficiency of transformation is a function of the cell concentration. Most of the surviving cells are competent with up to 80% transformed at high DNA concentration. The mechanism does not appear to include binding of the DNA to the cells prior to entry. Possible mechanisms are discussed and a simple procedure for the practical use of this technique is presented. PMID:3041370

  6. High-Efficiency Klystron For Television Transmitters

    NASA Technical Reports Server (NTRS)

    Ramins, Peter; Dayton, James; Mccune, Earl, Sr.; Kosmahl, Henry

    1990-01-01

    Improved klystron designed for use as final amplifier in ultrahigh-frequency (UHF) television transmitter. New device incorporates multistage depressed collector (MSDC) of advanced design to increase efficiency by recovering, from spent electron beam, some of residual kinetic energy otherwise dissipated as heat. Concept applied to increase efficiencies of microwave communication, equipment, radar systems, and particle-beam accelerators.

  7. Production of high intensity Beta beams at the ISOLDE facility

    SciTech Connect

    Hodak, Rastislav; Stora, Thierry; Mendonca, Tania M.

    2011-12-16

    We discuss a design study devoted to a construction of the Beta beams facility at CERN, a next generation European facility aiming for a production of pure and collimated ultra-relativistic beam of electron (anti)neutrinos with help of accelerated {beta}-decaying radioactive ions circulating in a storage decay ring. This high intense source of (anti)neutrinos directed towards a remote underground neutrino detector will allow to measure neutrino oscillations with high accuracy offering a unique chance for establishing a value of the {beta}{sub 13} mixing angle and CP violating phase. Recently, a significant progress have been achieved on the conceptual design of high power targets required for a production and an extraction of two baseline isotopes, {sup 6}He and {sup 18}Ne, at the unexampled rate of several 10{sup 13} ions/s. There is a possibility to produce these isotopes using the so-called Isotope Separation On Line (ISOL) method at the ISOLDE facility (CERN). The {sup 6}He production is realized by taking advantage of the {sup 9}Be(n,{alpha}){sup 6}He reaction and with help of spallation neutrons and porous BeO target material. The production of {sup 18}Ne through the {sup 19}F(p,2n){sup 18}Ne reaction at required intensities is even more challenging. Currently, a molten salt (NaF) loop target is proposed for a production of high rate of {sup 18}Ne required for the Beta beams project. The progress on the design study associated with new data and plans for future is briefly presented.

  8. High Performance Computing Facility Operational Assessment, CY 2011 Oak Ridge Leadership Computing Facility

    SciTech Connect

    Baker, Ann E; Barker, Ashley D; Bland, Arthur S Buddy; Boudwin, Kathlyn J.; Hack, James J; Kendall, Ricky A; Messer, Bronson; Rogers, James H; Shipman, Galen M; Wells, Jack C; White, Julia C; Hudson, Douglas L

    2012-02-01

    Oak Ridge National Laboratory's Leadership Computing Facility (OLCF) continues to deliver the most powerful resources in the U.S. for open science. At 2.33 petaflops peak performance, the Cray XT Jaguar delivered more than 1.4 billion core hours in calendar year (CY) 2011 to researchers around the world for computational simulations relevant to national and energy security; advancing the frontiers of knowledge in physical sciences and areas of biological, medical, environmental, and computer sciences; and providing world-class research facilities for the nation's science enterprise. Users reported more than 670 publications this year arising from their use of OLCF resources. Of these we report the 300 in this review that are consistent with guidance provided. Scientific achievements by OLCF users cut across all range scales from atomic to molecular to large-scale structures. At the atomic scale, researchers discovered that the anomalously long half-life of Carbon-14 can be explained by calculating, for the first time, the very complex three-body interactions between all the neutrons and protons in the nucleus. At the molecular scale, researchers combined experimental results from LBL's light source and simulations on Jaguar to discover how DNA replication continues past a damaged site so a mutation can be repaired later. Other researchers combined experimental results from ORNL's Spallation Neutron Source and simulations on Jaguar to reveal the molecular structure of ligno-cellulosic material used in bioethanol production. This year, Jaguar has been used to do billion-cell CFD calculations to develop shock wave compression turbo machinery as a means to meet DOE goals for reducing carbon sequestration costs. General Electric used Jaguar to calculate the unsteady flow through turbo machinery to learn what efficiencies the traditional steady flow assumption is hiding from designers. Even a 1% improvement in turbine design can save the nation billions of gallons of

  9. X-29 High Alpha Test in the National Transonic Facility

    NASA Technical Reports Server (NTRS)

    Underwood, Pamela J.; Owens, Lewis R.; Wahls, Richard A.; Williams, Susan

    2003-01-01

    This paper describes the X-29A research program at the National Transonic Facility. This wind tunnel test leveraged the X-29A high alpha flight test program by enabling ground-to-flight correlation studies with an emphasis on Reynolds number effects. The background and objectives of this test program, as well as the comparison of high Reynolds number wind tunnel data to X-29A flight test data are presented. The effects of Reynolds number on the forebody pressures at high angles of attack are also presented. The purpose of this paper is to document this test and serve as a reference for future ground-to-flight correlation studies, and high angle-of-attack investigations. Good ground-to-flight correlations were observed for angles of attack up to 50 deg, and Reynolds number effects were also observed.

  10. Location, use, and locational efficiency of health facilities in a Madras neighbourhood.

    PubMed

    Kumaran, V V

    1983-01-01

    The present paper has two related aims: an attempt to measure locational efficiency of health facilities in a Madras neighbourhood - Alandur - through an analysis of use patterns obtained from a questionnaire study, and an application of two significant methods on problems relating to organisation of health services - set covering reasoning and maximal covering location method. Some major conclusions of the two related analyses are: - Generally use declines with distance. However, beyond the eleventh distance zone, the use increases sharply, only to decrease after the fourteenth distance zone, the number of visits attributable to quality services at locations in these distance zones. - Among the variables determining the use patterns, distance is most important, followed by cost of treatment, the quality care, nature of facility and its availability. - Set covering method yielded 5 potential health location sites which proved to be efficient in both population coverage and maximum time distances of five and ten minutes /maximal covering location method/. Two alternative sets identified by set covering method proved to be inefficient on both population and distance counts when maximal covering method was applied.

  11. High efficiency quasi-monochromatic infrared emitter

    SciTech Connect

    Brucoli, Giovanni; Besbes, Mondher; Benisty, Henri Greffet, Jean-Jacques; Bouchon, Patrick; Haïdar, Riad

    2014-02-24

    Incandescent radiation sources are widely used as mid-infrared emitters owing to the lack of alternative for compact and low cost sources. A drawback of miniature hot systems such as membranes is their low efficiency, e.g., for battery powered systems. For targeted narrow-band applications such as gas spectroscopy, the efficiency is even lower. In this paper, we introduce design rules valid for very generic membranes demonstrating that their energy efficiency for use as incandescent infrared sources can be increased by two orders of magnitude.

  12. High Efficiency Submillimeter-Wave Imaging Array

    NASA Technical Reports Server (NTRS)

    Llombart, Nuria; Skalare, Anders; Gill, John J.; Siegel, Peter H.

    2008-01-01

    The period of a focal array is limited by the angular sampling and the f number of the system. This fact will limit the efficiency of imaging array systems to around 50%. Recently it been demonstrated that the use of a dielectric layer on top of an array of apertures can improve this efficiency limit. In this paper, we describe a similar structure that improves the efficiency in imaging applications and that it is easy to manufacture due to its compatibility with planar lithographic techniques.

  13. A high-efficiency energy conversion system

    SciTech Connect

    Belcher, A.E.

    1996-12-31

    A fundamentally new method for converting pressure into rotative motion is introduced. A historical background is given and an idealized non-turbine Brayton cycle engine and associated equations are described. Salient features are explained, together with suggested applications. Concerns over global warming, unacceptable levels of air pollution, and the need for more efficient utilization of nonrenewable energy resources, are issues which continue to plague us. The situation is further exacerbated by the possibility that underdeveloped countries, under pressure to expand their economies, might adopt power generating systems which could produce high levels of emissions. This scenario could easily develop if equipment, which once complied with stringent standards, failed to be adequately maintained through the absence of a reliable technical infrastructure. The Brayton cycle manometric engine has the potential for eliminating, or at least mitigating, many of the above issues. It is therefore of considerable importance to all populations, irrespective of demographic or economic considerations. This engine is inherently simple--the engine proper has only one moving part. It has no pistons, vanes, or other such conventional occlusive devices, yet it is a positive displacement machine. Sealing is achieved by what can best be described as a series of traveling U-tube manometers. Its construction does not require precision engineering nor the use of exotic materials, making it easy to maintain with the most rudimentary resources. Rotational velocity is low, and its normal life cycle is expected to extend to several decades. These advantages more than offset the machine`s large size. It is suited only to large and medium-scale stationary applications.

  14. Open air demolition of facilities highly contaminated with plutonium

    SciTech Connect

    Lloyd, E.R.; Lackey, M.B.; Stevens, J.M.; Zinsli, L.C.

    2007-07-01

    The demolition of highly contaminated plutonium buildings usually is a long and expensive process that involves decontaminating the building to near free- release standards and then using conventional methods to remove the structure. It doesn't, however, have to be that way. Fluor has torn down buildings highly contaminated with plutonium without excessive decontamination. By removing the select source term and fixing the remaining contamination on the walls, ceilings, floors, and equipment surfaces; open-air demolition is not only feasible, but it can be done cheaper, better (safer), and faster. Open-air demolition techniques were used to demolish two highly contaminated buildings to slab-on-grade. These facilities on the Department of Energy's Hanford Site were located in, or very near, compounds of operating nuclear facilities that housed hundreds of people working on a daily basis. To keep the facilities operating and the personnel safe, the projects had to be creative in demolishing the structures. Several key techniques were used to control contamination and keep it within the confines of the demolition area: spraying fixatives before demolition; applying fixative and misting with a fine spray of water as the buildings were being taken down; and demolishing the buildings in a controlled and methodical manner. In addition, detailed air-dispersion modeling was done to establish necessary building and meteorological conditions and to confirm the adequacy of the proposed methods. Both demolition projects were accomplished without any spread of contamination outside the modest buffer areas established for contamination control. Furthermore, personnel exposure to radiological and physical hazards was significantly reduced by using heavy equipment rather than 'hands on' techniques. (authors)

  15. OPEN AIR DEMOLITION OF FACILITIES HIGHLY CONTAMINATED WITH PLUTONIUM

    SciTech Connect

    LLOYD, E.R.

    2007-05-31

    The demolition of highly contaminated plutonium buildings usually is a long and expensive process that involves decontaminating the building to near free- release standards and then using conventional methods to remove the structure. It doesn't, however, have to be that way. Fluor has torn down buildings highly contaminated with plutonium without excessive decontamination. By removing the select source term and fixing the remaining contamination on the walls, ceilings, floors, and equipment surfaces; open-air demolition is not only feasible, but it can be done cheaper, better (safer), and faster. Open-air demolition techniques were used to demolish two highly contaminated buildings to slab-on-grade. These facilities on the Department of Energy's Hanford Site were located in, or very near, compounds of operating nuclear facilities that housed hundreds of people working on a daily basis. To keep the facilities operating and the personnel safe, the projects had to be creative in demolishing the structures. Several key techniques were used to control contamination and keep it within the confines of the demolition area: spraying fixatives before demolition; applying fixative and misting with a fine spray of water as the buildings were being taken down; and demolishing the buildings in a controlled and methodical manner. In addition, detailed air-dispersion modeling was done to establish necessary building and meteorological conditions and to confirm the adequacy of the proposed methods. Both demolition projects were accomplished without any spread of contamination outside the modest buffer areas established for contamination control. Furthermore, personnel exposure to radiological and physical hazards was significantly reduced by using heavy equipment rather than ''hands on'' techniques.

  16. A High Efficiency Grazing Incidence Pumped X-ray Laser

    SciTech Connect

    Dunn, J; Keenan, R; Price, D F; Patel, P K; Smith, R F; Shlyaptsev, V N

    2006-08-31

    The main objective of the project is to demonstrate a proof-of-principle, new type of high efficiency, short wavelength x-ray laser source that will operate at unprecedented high repetition rates (10Hz) that could be scaled to 1kHz or higher. The development of a high average power, tabletop x-ray laser would serve to complement the wavelength range of 3rd and future 4th generation light sources, e.g. the LCLS, being developed by DOE-Basic Energy Sciences. The latter are large, expensive, central, synchrotron-based facilities while the tabletop x-ray laser is compact, high-power laser-driven, and relatively inexpensive. The demonstration of such a unique, ultra-fast source would allow us to attract funding from DOE-BES, NSF and other agencies to pursue probing of diverse materials undergoing ultrafast changes. Secondly, this capability would have a profound impact on the semiconductor industry since a coherent x-ray laser source would be ideal for ''at wavelength'' {approx}13 nm metrology and microscopy of optics and masks used in EUV lithography. The project has major technical challenges. We will perform grazing-incidence pumped laser-plasma experiments in flat or groove targets which are required to improve the pumping efficiency by ten times. Plasma density characterization using our existing unique picosecond x-ray laser interferometry of laser-irradiated targets is necessary. Simulations of optical laser propagation as well as x-ray laser production and propagation through freely expanding and confined plasma geometries are essential. The research would be conducted using the Physics Directorate Callisto and COMET high power lasers. At the end of the project, we expect to have a high-efficiency x-ray laser scheme operating below 20 nm at 10Hz with a pulse duration of {approx}2 ps. This will represent the state-of-the-art in x-ray lasers and would be a major step forward from our present picosecond laser-driven x-ray lasers. There is an added bonus of creating

  17. Facile and efficient reprogramming of ciliary body epithelial cells into induced pluripotent stem cells.

    PubMed

    Ni, Aiguo; Wu, Ming Jing; Nakanishi, Yuka; Chavala, Sai H

    2013-09-15

    Induced pluripotent stem (iPS) cells are attractive for cell replacement therapy, because they overcome ethical and immune rejection issues that are associated with embryonic stem cells. iPS cells have been derived from autonomous fibroblasts at low efficiency using multiple ectopic transcription factors. Recent evidence suggests that the epigenome of donor cell sources plays an important role in the reprogramming and differentiation characteristics of iPS cells. Thus, identification of somatic cell types that are easily accessible and are more amenable for cellular reprogramming is critical for regenerative medicine applications. Here, we identify ciliary body epithelial cells (CECs) as a new cell type for iPS cell generation that has higher reprogramming efficiency compared with fibroblasts. The ciliary body is composed of epithelial cells that are located in the anterior portion of the eye at the level of the lens and is readily surgically accessible. CECs also have a reduced reprogramming requirement, as we demonstrate that ectopic Sox2 and c-Myc are dispensable. Enhanced reprogramming efficiency may be due to increased basal levels of Sox2 in CECs. In addition, we are the first to report a cellular reprogramming haploinsufficiency observed when reprogramming with fewer factors (Oct4 and Klf4) in Sox2 hemizygous cells. Taken together, endogenous Sox2 levels are critical for the enhanced efficiency and reduced exogenous requirement that permit facile cellular reprogramming of CECs.

  18. High efficiency silicon solar cell review

    NASA Technical Reports Server (NTRS)

    Godlewski, M. P. (Editor)

    1975-01-01

    An overview is presented of the current research and development efforts to improve the performance of the silicon solar cell. The 24 papers presented reviewed experimental and analytic modeling work which emphasizes the improvment of conversion efficiency and the reduction of manufacturing costs. A summary is given of the round-table discussion, in which the near- and far-term directions of future efficiency improvements were discussed.

  19. High Efficient Cryocooler for Liquid Hydrogen System

    NASA Astrophysics Data System (ADS)

    Nakagome, H.

    2006-04-01

    Conversion into Hydrogen Energy Society is advanced focusing on the application to a fuel cell electric vehicle. As volume and weight density of liquid hydrogen are large, it is the method which was most excellent as the storage method of hydrogen. However, in order to store liquid hydrogen stably over a long period of time, decreasing the loss of energy, development of an efficient small cryocooler becomes important. This paper reports the research about improvement in the refrigeration efficiency of a two-stage GM cryocooler. In order that the GM cryocooler may operate by the Simon expansion, it carries out asymptotic of the COP of the GM cryocooler to the Carnot COP as a compression ratio is lowered. When experimented based on this view, it was checked that refrigeration efficiency rises with reduction in a compression ratio. Furthermore, if the compression ratio is lowered, refrigeration efficiency will fall rapidly. The peak value of the refrigeration efficiency in 20K level attained 28%Carnot. It was verified by optimization of the compression ratio of the GM cryocooler that refrigeration efficiency can be improved significantly. Therefore, sharp reduction of the energy consumption of a liquid hydrogen system will be attained by applying the result of this research.

  20. A ternary TiO2/WO3/graphene nanocomposite adsorbent: facile preparation and efficient removal of Rhodamine B

    NASA Astrophysics Data System (ADS)

    Zhang, Yong-qiang; Li, Xiao-hui; Lü, Jie; Si, Chong-dian; Liu, Guang-jun; Gao, Hong-tao; Wang, Pi-bo

    2014-08-01

    Ternary TiO2/WO3/graphene (TWG) nanocomposites were prepared by a facile salt-ultrasonic assisted hydrothermal method. The products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption-desorption. Both anatase TiO2 and orthorhombic WO3 formed in the nanocomposites, along with a highly disordered overlay of individual graphene nanosheets. Polyhedral and spherical TiO2 and WO3 nanoparticles of uniform size 10-30 nm were densely anchored to the graphene sheets. The maximum specific surface area of the products was 144.59 m2·g-1. The products showed clear abilities for the removal of Rhodamine B in the absence of illumination. Furthermore, the adsorption activity of the products exhibited only a slight decrease after three successive cycles. The results demonstrate that the ternary nanocomposites could be used as a high-efficiency adsorbent for the removal of environmental contaminants.

  1. Opportunities for Energy Efficiency and Open Automated Demand Response in Wastewater Treatment Facilities in California -- Phase I Report

    SciTech Connect

    Lekov, Alex; Thompson, Lisa; McKane, Aimee; Song, Katherine; Piette, Mary Ann

    2009-04-01

    This report summarizes the Lawrence Berkeley National Laboratory?s research to date in characterizing energy efficiency and automated demand response opportunities for wastewater treatment facilities in California. The report describes the characteristics of wastewater treatment facilities, the nature of the wastewater stream, energy use and demand, as well as details of the wastewater treatment process. It also discusses control systems and energy efficiency and automated demand response opportunities. In addition, several energy efficiency and load management case studies are provided for wastewater treatment facilities.This study shows that wastewater treatment facilities can be excellent candidates for open automated demand response and that facilities which have implemented energy efficiency measures and have centralized control systems are well-suited to shift or shed electrical loads in response to financial incentives, utility bill savings, and/or opportunities to enhance reliability of service. Control technologies installed for energy efficiency and load management purposes can often be adapted for automated demand response at little additional cost. These improved controls may prepare facilities to be more receptive to open automated demand response due to both increased confidence in the opportunities for controlling energy cost/use and access to the real-time data.

  2. Efficiency of antenatal care and childbirth services in selected primary health care facilities in rural Tanzania: a cross-sectional study

    PubMed Central

    2014-01-01

    Background Cost studies are paramount for demonstrating how resources have been spent and identifying opportunities for more efficient use of resources. The main objective of this study was to assess the actual dimension and distribution of the costs of providing antenatal care (ANC) and childbirth services in selected rural primary health care facilities in Tanzania. In addition, the study analyzed determining factors of service provision efficiency in order to inform health policy and planning. Methods This was a retrospective quantitative cross-sectional study conducted in 11 health centers and dispensaries in Lindi and Mtwara rural districts. Cost analysis was carried out using step down cost accounting technique. Unit costs reflected efficiency of service provision. Multivariate regression analysis on the drivers of observed relative efficiency in service provision between the study facilities was conducted. Reported personnel workload was also described. Results The health facilities spent on average 7 USD per capita in 2009. As expected, fewer resources were spent for service provision at dispensaries than at health centers. Personnel costs contributed a high approximate 44% to total costs. ANC and childbirth consumed approximately 11% and 12% of total costs; and 8% and 10% of reported service provision time respectively. On average, unit costs were rather high, 16 USD per ANC visit and 79.4 USD per childbirth. The unit costs showed variation in relative efficiency in providing the services between the health facilities. The results showed that efficiency in ANC depended on the number of staff, structural quality of care, process quality of care and perceived quality of care. Population-staff ratio and structural quality of basic emergency obstetric care services highly influenced childbirth efficiency. Conclusions Differences in the efficiency of service provision present an opportunity for efficiency improvement. Taking into consideration client

  3. High Efficiency Large Area Polysilicon Solar Cells

    NASA Technical Reports Server (NTRS)

    Johnson, S. M.; Winter, C.

    1985-01-01

    Large area (100 sq cm) polysilicon solar cells having efficiencies of up to 14.1% (100 mW/sq cm, 25 C) were fabricated and a detailed analysis was performed to identify the efficiency loss mechanisms. The 1-5 characteristics of the best cell were dominated by recombination in the quasi-neutral base due to the combination of minority carrier diffusion length and base resistivity. An analysis of the microstructural defects present in the material and their effect on the electrical properties is presented.

  4. [A novel and facile microchip based on nitrocellulose membrane toward efficient capture of circulating tumor cells].

    PubMed

    Zhang, Peng; Sun, Changlong; Zhang, Ren; Gao, Mingxia; Zhang, Xiangmin

    2013-06-01

    A novel and facile circulating tumor cell (CTC) microchip has been developed for the isolation and detection of cancer cells. The CTC microchip was prepared based on the nitrocellulose membrane substrate, which shows high affinity to proteins and hence can adsorb antibodies naturally. We employed non-small-cells of lung cancer NCI-H1650 as target cells and testified the high capture efficacy of the CTC microchip. Furthermore, we spiked 500 cancer cells to 1 mL healthy donor's whole blood in order to simulate the detection of CTC in patient and detected 182 cancer cells ultimately, indicating the huge application potential in the future.

  5. High efficiency germanium-assisted grating coupler.

    PubMed

    Yang, Shuyu; Zhang, Yi; Baehr-Jones, Tom; Hochberg, Michael

    2014-12-15

    We propose a fiber to submicron silicon waveguide vertical coupler utilizing germanium-on-silicon gratings. The germanium is epitaxially grown on silicon in the same step for building photodetectors. Coupling efficiency based on FDTD simulation is 76% at 1.55 µm and the optical 1dB bandwidth is 40 nm.

  6. High-Tech Means High-Efficiency: The Business Case for EnergyManagement in High-Tech Industries

    SciTech Connect

    Shanshoian, Gary; Blazek, Michele; Naughton, Phil; Seese, RobertS.; Mills, Evan; Tschudi, William

    2005-11-15

    In the race to apply new technologies in ''high-tech'' facilities such as data centers, laboratories, and clean rooms, much emphasis has been placed on improving service, building capacity, and increasing speed. These facilities are socially and economically important, as part of the critical infrastructure for pharmaceuticals,electronics, communications, and many other sectors. With a singular focus on throughput, some important design issues can be overlooked, such as the energy efficiency of individual equipment (e.g., lasers, routers and switches) as well as the integration of high-tech equipment into the power distribution system and the building envelope. Among technology-based businesses, improving energy efficiency presents an often untapped opportunity to increase profits, enhance process control,maximize asset value, improve the work place environment, and manage a variety of business risks. Oddly enough, the adoption of energy efficiency improvements in this sector lags behind many others. As a result, millions of dollars are left on the table with each year ofoperation.

  7. Energy efficiency indicators for high electric-load buildings

    SciTech Connect

    Aebischer, Bernard; Balmer, Markus A.; Kinney, Satkartar; Le Strat, Pascale; Shibata, Yoshiaki; Varone, Frederic

    2003-06-01

    Energy per unit of floor area is not an adequate indicator for energy efficiency in high electric-load buildings. For two activities, restaurants and computer centres, alternative indicators for energy efficiency are discussed.

  8. The Greening of a Plutonium Facility through Personnel Safety, Operational Efficiency, and Infrastructure Improvements - 12108

    SciTech Connect

    Dodge, Robert L.; Cournoyer, Michael E.

    2012-07-01

    Chemical and metallurgical operations involving plutonium and other hazardous materials account for most activities performed at the Los Alamos National Laboratory's Plutonium Facility (TA-55). Engineered barriers provide the most effective protection from hazardous materials. These safety features serve to protect workers and provide defense in depth against the hazards associated with operations. Although not designed to specifically meet environmental requirements the safety-based design does meet or exceed the requirements of the environmental regulations enacted during and since its construction. TA-55's Waste Services Group supports this safety methodology by ensuring safe, efficient and compliant management of all radioactive and hazardous wastes generated at the TA-55. A key function of this group is the implementation of measures that lower the overall risk of radiological and hazardous material operations. Processes and procedures that reduce waste generation compared to current, prevalent processes or procedures used for the same purpose are identified. Some of these 'Best Practices' include implementation of a chemical control system, elimination of aerosol cans, reduction in hazardous waste, implementation of zero liquid discharge, and the re-cyclization of nitric acid. P2/WMin opportunities have been implemented in the areas of personnel and facility attributes, environmental compliance, energy conservation, and green focused infrastructure expansion with the overall objective of minimizing raw material and energy consumption and waste generation. This increases technical knowledge and augments operational safety. (authors)

  9. Highly Efficient Self-Replicating RNA Enzymes

    PubMed Central

    Robertson, Michael P.; Joyce, Gerald F.

    2014-01-01

    SUMMARY An RNA enzyme has been developed that catalyzes the joining of oligonucleotide substrates to form additional copies of itself, undergoing self-replication with exponential growth. The enzyme also can cross-replicate with a partner enzyme, resulting in their mutual exponential growth and enabling self-sustained Darwinian evolution. The opportunity for inventive evolution within this synthetic genetic system depends on the diversity of the evolving population, which is limited by the catalytic efficiency of the enzyme. Directed evolution was used to improve the efficiency of the enzyme and increase its exponential growth rate to 0.14 min−1, corresponding to a doubling time of 5 min. This is close to the limit of 0.21 min−1 imposed by the rate of product release, but sufficient to enable more than 80 logs of growth per day. PMID:24388759

  10. Highly Efficient Protein Misfolding Cyclic Amplification

    PubMed Central

    Ostapchenko, Valeriy G.; Savtchenk, Regina; Alexeeva, Irina; Rohwer, Robert G.; Baskakov, Ilia V.

    2011-01-01

    Protein misfolding cyclic amplification (PMCA) provides faithful replication of mammalian prions in vitro and has numerous applications in prion research. However, the low efficiency of conversion of PrPC into PrPSc in PMCA limits the applicability of PMCA for many uses including structural studies of infectious prions. It also implies that only a small sub-fraction of PrPC may be available for conversion. Here we show that the yield, rate, and robustness of prion conversion and the sensitivity of prion detection are significantly improved by a simple modification of the PMCA format. Conducting PMCA reactions in the presence of Teflon beads (PMCAb) increased the conversion of PrPC into PrPSc from ∼10% to up to 100%. In PMCAb, a single 24-hour round consistently amplified PrPSc by 600-700-fold. Furthermore, the sensitivity of prion detection in one round (24 hours) increased by 2-3 orders of magnitude. Using serial PMCAb, a 1012-fold dilution of scrapie brain material could be amplified to the level detectible by Western blotting in 3 rounds (72 hours). The improvements in amplification efficiency were observed for the commonly used hamster 263K strain and for the synthetic strain SSLOW that otherwise amplifies poorly in PMCA. The increase in the amplification efficiency did not come at the expense of prion replication specificity. The current study demonstrates that poor conversion efficiencies observed previously have not been due to the scarcity of a sub-fraction of PrPC susceptible to conversion nor due to limited concentrations of essential cellular cofactors required for conversion. The new PMCAb format offers immediate practical benefits and opens new avenues for developing fast ultrasensitive assays and for producing abundant quantities of PrPSc in vitro. PMID:21347353

  11. High efficiency air cycle air conditioning system

    SciTech Connect

    Rannenberg, G. C.

    1985-11-19

    An air cycle air conditioning system is provided with regenerative heat exchangers upstream and downstream of an expansion turbine. A closedloop liquid circulatory system serially connects the two regenerative heat exchangers for regeneration without the bulk associated with air-to-air heat exchange. The liquid circulatory system may also provide heat transport to a remote sink heat exchanger and from a remote load as well as heat exchange within the sink heat exchanger and load for enhanced compactness and efficiency.

  12. Comparison of Two High Intensity Acoustic Test Facilities

    NASA Astrophysics Data System (ADS)

    Launay, A.; Tadao Sakita, M.; Kim, Youngkey K.

    2004-08-01

    In two different countries, at the same period of time, the institutes in charge of the development of space activities have decided to extend their satellite integration and test center, and to implement a reverberant acoustic chamber. In Brazil the INPE laboratory (LIT : Laboratorio de Integracao e Testes) and in South Korea the KARI laboratory (SITC : Satellite Integration and Test Center) started their projects in July 2000 for the RATF (Reverberant Acoustic Test Facility) and in May 2001 for the HIAC (High Intensity Acoustic Chamber) respectively, writing the technical specifications. The kick-off meetings took place in December 2000 and in February 2002 and the opening ceremonies in December 19, 2002 in Brazil and in August 22, 2003 in Korea. This paper compares the two projects in terms of design choices, manufacturing processes, equipment installed and technical final characteristics.

  13. An Experimental Test Facility to Support Development of the Fluoride Salt Cooled High Temperature Reactor

    SciTech Connect

    Yoder Jr, Graydon L; Aaron, Adam M; Cunningham, Richard Burns; Fugate, David L; Holcomb, David Eugene; Kisner, Roger A; Peretz, Fred J; Robb, Kevin R; Wilgen, John B; Wilson, Dane F

    2014-01-01

    The need for high-temperature (greater than 600 C) energy exchange and delivery systems is significantly increasing as the world strives to improve energy efficiency and develop alternatives to petroleum-based fuels. Liquid fluoride salts are one of the few energy transport fluids that have the capability of operating at high temperatures in combination with low system pressures. The Fluoride Salt-Cooled High-Temperature Reactor design uses fluoride salt to remove core heat and interface with a power conversion system. Although a significant amount of experimentation has been performed with these salts, specific aspects of this reactor concept will require experimental confirmation during the development process. The experimental facility described here has been constructed to support the development of the Fluoride Salt Cooled High Temperature Reactor concept. The facility is capable of operating at up to 700 C and incorporates a centrifugal pump to circulate FLiNaK salt through a removable test section. A unique inductive heating technique is used to apply heat to the test section, allowing heat transfer testing to be performed. An air-cooled heat exchanger removes added heat. Supporting loop infrastructure includes a pressure control system; trace heating system; and a complement of instrumentation to measure salt flow, temperatures, and pressures around the loop. The initial experiment is aimed at measuring fluoride salt heat transfer inside a heated pebble bed similar to that used for the core of the pebble bed advanced high-temperature reactor. This document describes the details of the loop design, auxiliary systems used to support the facility, the inductive heating system, and facility capabilities.

  14. High Efficiency Electron-Laser Interactions in Tapered Helical Undulators

    NASA Astrophysics Data System (ADS)

    Duris, Joseph Patrick

    Efficient coupling of relativistic electron beams with high power radiation lies at the heart of advanced accelerator and light source research and development. The inverse free electron laser is a stable accelerator capable of harnessing very high intensity laser electric fields to efficiently transfer large powers from lasers to electron beams. In this dissertation, we first present the theoretical framework to describe the interaction, and then apply our improved understanding of the IFEL to the design and numerical study of meter-long, GeV IFELs for compact light sources. The central experimental work of the dissertation is the UCLA BNL helical inverse free electron laser experiment at the Accelerator Test Facility in Brookhaven National Laboratory which used a strongly tapered 54cm long, helical, permanent magnet undulator and a several hundred GW CO2 laser to accelerate electrons from 52 to 106MeV, setting new records for inverse free electron laser energy gain (54MeV) and average accelerating gradient (100MeV/m). The undulator design and fabrication as well as experimental diagnostics are presented. In order to improve the stability and quality of the accelerated electron beam, we redesigned the undulator for a slightly reduced output energy by modifying the magnet gap throughout the undulator, and we used this modified undulator to demonstrated capture of >25% of the injected beam without prebunching. In the study of heavily loaded GeV inverse free electron lasers, we show that a majority of the power may be transferred from a laser to the accelerated electron beam. Reversing the process to decelerate high power electron beams, a mechanism we refer to as tapering enhanced stimulated superradiant amplification, offers a clear path to high power light sources. We present studies of radiation production for a wide range of wavelengths (10mum, 13nm, and 0.3nm) using this method and discuss the design for a deceleration experiment using the same undulator used

  15. Development of a pollution prevention and energy efficiency clearinghouse for biomedical research facilities.

    PubMed Central

    Barker, L F; Rau, E H; Pfister, E A; Calcagni, J

    2000-01-01

    This is the report of the National Association of Physicians for the Environment Committee on Development of a Pollution Prevention and Energy Efficiency Clearinghouse for Biomedical Research Facilities from the Leadership Conference on Biomedical Research and the Environment held at the National Institutes of Health in Bethesda, Maryland, on 1--2 November 1999. A major goal of the conference was the establishment of a World Wide Web-based clearinghouse, which would lend tremendous resources to the biomedical research community by providing access to a database of peer-reviewed articles and references dealing with a host of aspects of biomedical research relating to energy efficiency, pollution prevention, and waste reduction. A temporary website has been established with the assistance of the U.S. Environmental Protection Agency (EPA) Regions III and IV, where a pilot site provides access to the EPA's existing databases on these topics. A system of peer review for articles and promising techniques still must be developed, but a glimpse of topics and search engines is available for comment and review on the EPA Region IV-supported website (http://wrrc.p2pays.org/). PMID:11121361

  16. Direct drive implosion experiments on SGIII prototype laser facility: Assessing energy coupling efficiency and implosion symmetry

    SciTech Connect

    Pu Yudong; Huang Tianxuan; Li Huang; Zhan Xiayu; Peng Xiaoshi; Tang Qi; Song Zifeng; Chen Jiabin; Song Tianming; Chen Ming; Yu Ruizhen; He Xiaoan; Li Chaoguang; Zhang Lu; Zheng Jiahua; Jing Longfei; Chen Bolun; Su Ming; Jiang Wei; Yu Bo; and others

    2012-07-15

    Direct drive implosion experiments were conducted on SGIII prototype laser facility. From the time resolved x-ray images, the bright ring and the central bright spot are observed. The radial velocity of the convergent bright ring indicates the shell velocity, and the times when the central bright spot is first seen and becomes most intensive indicate the times of shock convergence and later stagnation, respectively. Radiation hydrodynamic simulations were carried out by changing laser energy deposition factors. When the simulated results are brought close to the measured ones, it is found that the energy coupling efficiency is around 70%. The implosion symmetry is indicated by the core x-ray emission pattern which is pancake when viewing from the equator, and splits into several bright spots when viewing close to the pole. A simple model is developed to understand this asymmetry. It is speculated that the observed implosion asymmetry can be attributed to the laser arrangement which is originally designed for indirect drive experiments. Further improvements of energy coupling efficiency and implosion symmetry in future experiments can be achieved by optimizing target design and laser arrangement.

  17. A high-efficiency mode coupler autotracking feed

    NASA Astrophysics Data System (ADS)

    Cipolla, Frank; Seck, Gerry

    The design, construction, and installation of high-efficiency autotracking feeds using a tracking mode coupler at both S, C, and X band are presented. These feeds have shown greater than 65 percent efficiencies when mounted in a doubly shaped dual reflector antenna. The mode coupler feed attributes include high-efficiency in both the data and track channels, full waveguide bandwidth operation, good feed error gradients, high-power handling, and active cross talk correction.

  18. High Efficiency Thermoelectric Radioisotope Power Systems

    NASA Technical Reports Server (NTRS)

    El-Genk, Mohamed; Saber, Hamed; Caillat, Thierry

    2004-01-01

    The work performed and whose results presented in this report is a joint effort between the University of New Mexico s Institute for Space and Nuclear Power Studies (ISNPS) and the Jet Propulsion Laboratory (JPL), California Institute of Technology. In addition to the development, design, and fabrication of skutterudites and skutterudites-based segmented unicouples this effort included conducting performance tests of these unicouples for hundreds of hours to verify theoretical predictions of the conversion efficiency. The performance predictions of these unicouples are obtained using 1-D and 3-D models developed for that purpose and for estimating the actual performance and side heat losses in the tests conducted at ISNPS. In addition to the performance tests, the development of the 1-D and 3-D models and the development of Advanced Radioisotope Power systems for Beginning-Of-Life (BOM) power of 108 We are carried out at ISNPS. The materials synthesis and fabrication of the unicouples are carried out at JPL. The research conducted at ISNPS is documented in chapters 2-5 and that conducted at JP, in documented in chapter 5. An important consideration in the design and optimization of segmented thermoelectric unicouples (STUs) is determining the relative lengths, cross-section areas, and the interfacial temperatures of the segments of the different materials in the n- and p-legs. These variables are determined using a genetic algorithm (GA) in conjunction with one-dimensional analytical model of STUs that is developed in chapter 2. Results indicated that when optimized for maximum conversion efficiency, the interfacial temperatures between various segments in a STU are close to those at the intersections of the Figure-Of-Merit (FOM), ZT, curves of the thermoelectric materials of the adjacent segments. When optimizing the STUs for maximum electrical power density, however, the interfacial temperatures are different from those at the intersections of the ZT curves, but

  19. Analysis of the DNA sequencing quality and efficiency of the Apollo100 robotic microcycler in a core facility setting.

    PubMed

    Logsdon, M E; Trounstine, M C; Zianni, M R

    2011-07-01

    Sanger, or dideoxynucleotide sequencing, is an important tool for biomolecular research. An important trend in DNA sequencing is to find new and innovative ways to provide high-quality, reliable sequences in a more efficient manner, using automated capillary electrophoresis. The Apollo100 combines Sanger cycle sequencing and solid-phase reversible immobilization for product purification in a single instrument with robotic liquid handling and microfluidic (Microscale On-chip Valve) chips that have onboard thermal cycling and pneumatic mixing. Experiments were performed to determine how the DNA sequencing results from the Apollo100 compared with conventional, manual methods used in a core facility setting. Through rigorous experimentation of multiple baseline runs and a dilution series of template concentration, the Apollo100 generated sequencing that exceeded 900 bases with a quality score of 20 or above. When comparing actual client samples of amplicons, plasmids, and cosmids, Apollo100 sequencing results did not differ significantly from those reactions prepared manually. In addition, bacterial genomic DNA was sequenced successfully, directly with the Apollo100, although results were of lower quality than the standard manual method. As a result of the microscale capabilities, the Apollo100 offers valuable savings with respect to the quantity of reagents consumed compared with current manual sequencing methods, thereby continuing the demand for smaller template and reagent requirements. In conclusion, the Apollo100 can generate high-quality DNA sequences for common templates equivalent to those produced using manual sequencing methods and increases efficiency through reduced labor and reagents.

  20. High Performance Computing Facility Operational Assessment, FY 2010 Oak Ridge Leadership Computing Facility

    SciTech Connect

    Bland, Arthur S Buddy; Hack, James J; Baker, Ann E; Barker, Ashley D; Boudwin, Kathlyn J.; Kendall, Ricky A; Messer, Bronson; Rogers, James H; Shipman, Galen M; White, Julia C

    2010-08-01

    Oak Ridge National Laboratory's (ORNL's) Cray XT5 supercomputer, Jaguar, kicked off the era of petascale scientific computing in 2008 with applications that sustained more than a thousand trillion floating point calculations per second - or 1 petaflop. Jaguar continues to grow even more powerful as it helps researchers broaden the boundaries of knowledge in virtually every domain of computational science, including weather and climate, nuclear energy, geosciences, combustion, bioenergy, fusion, and materials science. Their insights promise to broaden our knowledge in areas that are vitally important to the Department of Energy (DOE) and the nation as a whole, particularly energy assurance and climate change. The science of the 21st century, however, will demand further revolutions in computing, supercomputers capable of a million trillion calculations a second - 1 exaflop - and beyond. These systems will allow investigators to continue attacking global challenges through modeling and simulation and to unravel longstanding scientific questions. Creating such systems will also require new approaches to daunting challenges. High-performance systems of the future will need to be codesigned for scientific and engineering applications with best-in-class communications networks and data-management infrastructures and teams of skilled researchers able to take full advantage of these new resources. The Oak Ridge Leadership Computing Facility (OLCF) provides the nation's most powerful open resource for capability computing, with a sustainable path that will maintain and extend national leadership for DOE's Office of Science (SC). The OLCF has engaged a world-class team to support petascale science and to take a dramatic step forward, fielding new capabilities for high-end science. This report highlights the successful delivery and operation of a petascale system and shows how the OLCF fosters application development teams, developing cutting-edge tools and resources for next

  1. A high-efficiency double quantum dot heat engine

    NASA Astrophysics Data System (ADS)

    Liu, Y. S.; Yang, X. F.; Hong, X. K.; Si, M. S.; Chi, F.; Guo, Y.

    2013-08-01

    High-efficiency heat engine requires a large output power at the cost of less input heat energy as possible. Here we propose a heat engine composed of serially connected two quantum dots sandwiched between two metallic electrodes. The efficiency of the heat engine can approach the maximum allowable Carnot efficiency ηC. We also find that the strong intradot Coulomb interaction can induce additional work regions for the heat engine, whereas the interdot Coulomb interaction always suppresses the efficiency. Our results presented here indicate a way to fabricate high-efficiency quantum-dot thermoelectric devices.

  2. Highly efficient photodimerization of olefins in a nanotemplate on HOPG by scanning tunneling microscopy.

    PubMed

    Xue, JinDong; Xu, Jing; Hu, FangYun; Liao, LingYan; Li, Min; Duan, WuBiao; Zeng, QingDao; Wang, Chen

    2014-12-21

    Efficient photochemical reactions on a surface are of great importance for their potential applications in optoelectronic devices. In this work, a highly efficient photodimerization reaction of an olefin cocrystal built from two trans-1,2-bis(4-pyridyl)ethylenes (4,4'-bpe) and two isophthalic acid molecules via N···H-O hydrogen bonds in between was achieved in a nanotemplate on a highly oriented pyrolytic graphite (HOPG) surface. 4,4'-Bpe molecules first undergo the trans-cis isomerization followed by [2+2] photodimerization in the nanotemplate on HOPG upon UV irradiation. The efficiency of the isomerization as well as the photodimerization in the presence of the nanotemplate is much higher than that in its absence. These results provide a facile way to achieve highly efficient photodimerization of olefins on a large scale on surfaces.

  3. Recovery Act: High-Efficiency, Wideband Three-Phase Rectifiers and Adaptive Rectifier Management for Telecomm Central Office and Large Data Center Applications

    SciTech Connect

    Mark A. Johnson

    2012-06-29

    Lineage Power and Verizon teamed up to address a DOE funding opportunity focused on improving the power conversion chain in telecommunications facilities and data centers. The project had three significant elements: the design and development of high efficiency and high power three-phase rectifiers by Lineage Power, design and development of software to optimize overall plant energy efficiency by Lineage Power, and a field trial in active Verizon telecommunications facilities where energy consumption was measured before and after efficiency upgrades.

  4. Development of high-efficiency solar cells on silicon web

    NASA Technical Reports Server (NTRS)

    Rohatgi, A.; Meier, D. L.; Campbell, R. B.; Seidensticker, R. G.; Rai-Choudhury, P.

    1985-01-01

    High-efficiency dendritic cells were discussed. The influence of twin planes and heat treatment on the location and effect of trace impurities was of particular interest. Proper heat treatment often increases efficiency by causing impurities to pile up at twin planes. Oxide passivation had a beneficial effect on efficiency. A very efficient antireflective (AR) coating of zinc selenide and magnesium fluoride was designed and fabricated. An aluminum back-surface reflector was also effective.

  5. Efficient high-capacity steganography technique

    NASA Astrophysics Data System (ADS)

    Abdulla, Alan A.; Jassim, Sabah A.; Sellahewa, Harin

    2013-05-01

    Performance indicators characterizing modern steganographic techniques include capacity (i.e. the quantity of data that can be hidden in the cover medium), stego quality (i.e. artifacts visibility), security (i.e. undetectability), and strength or robustness (intended as the resistance against active attacks aimed to destroy the secret message). Fibonacci based embedding techniques have been researched and proposed in the literature to achieve efficient steganography in terms of capacity with respect to stego quality. In this paper, we investigated an innovative idea that extends Fibonacci-like steganography by bit-plane(s) mapping instead of bit-plane(s) replacement. Our proposed algorithm increases embedding capacity using bit-plane mapping to embed two bits of the secret message in three bits of a pixel of the cover, at the expense of a marginal loss in stego quality. While existing Fibonacci embedding algorithms do not use certain intensities of the cover for embedding due to the limitation imposed by the Zeckendorf theorem, our proposal solve this problem and make all intensity values candidates for embedding. Experimental results demonstrate that the proposed technique double the embedding capacity when compared to existing Fibonacci methods, and it is secure against statistical attacks such as RS, POV, and difference image histogram (DIH).

  6. Future carbon beams at SPIRAL1 facility: which method is the most efficient?

    PubMed

    Maunoury, L; Delahaye, P; Angot, J; Dubois, M; Dupuis, M; Frigot, R; Grinyer, J; Jardin, P; Leboucher, C; Lamy, T

    2014-02-01

    Compared to in-flight facilities, Isotope Separator On-Line ones can in principle produce significantly higher radioactive ion beam intensities. On the other hand, they have to cope with delays for the release and ionization which make the production of short-lived isotopes ion beams of reactive and refractory elements particularly difficult. Many efforts are focused on extending the capabilities of ISOL facilities to those challenging beams. In this context, the development of carbon beams is triggering interest [H. Frånberg, M. Ammann, H. W. Gäggeler, and U. Köster, Rev. Sci. Instrum. 77, 03A708 (2006); M. Kronberger, A. Gottberg, T. M. Mendonca, J. P. Ramos, C. Seiffert, P. Suominen, and T. Stora, in Proceedings of the EMIS 2012 [Nucl. Instrum. Methods Phys. Res. B Production of molecular sideband radioisotope beams at CERN-ISOLDE using a Helicon-type plasma ion source (to be published)]: despite its refractory nature, radioactive carbon beams can be produced from molecules (CO or CO2), which can subsequently be broken up and multi-ionized to the required charge state in charge breeders or ECR sources. This contribution will present results of experiments conducted at LPSC with the Phoenix charge breeder and at GANIL with the Nanogan ECR ion source for the ionization of carbon beams in the frame of the ENSAR and EMILIE projects. Carbon is to date the lightest condensable element charge bred with an ECR ion source. Charge breeding efficiencies will be compared with those obtained using Nanogan ECRIS and charge breeding times will be presented as well. PMID:24593427

  7. Future carbon beams at SPIRAL1 facility: Which method is the most efficient?

    NASA Astrophysics Data System (ADS)

    Maunoury, L.; Delahaye, P.; Angot, J.; Dubois, M.; Dupuis, M.; Frigot, R.; Grinyer, J.; Jardin, P.; Leboucher, C.; Lamy, T.

    2014-02-01

    Compared to in-flight facilities, Isotope Separator On-Line ones can in principle produce significantly higher radioactive ion beam intensities. On the other hand, they have to cope with delays for the release and ionization which make the production of short-lived isotopes ion beams of reactive and refractory elements particularly difficult. Many efforts are focused on extending the capabilities of ISOL facilities to those challenging beams. In this context, the development of carbon beams is triggering interest [H. Frånberg, M. Ammann, H. W. Gäggeler, and U. Köster, Rev. Sci. Instrum. 77, 03A708 (2006); M. Kronberger, A. Gottberg, T. M. Mendonca, J. P. Ramos, C. Seiffert, P. Suominen, and T. Stora, in Proceedings of the EMIS 2012 [Nucl. Instrum. Methods Phys. Res. B Production of molecular sideband radioisotope beams at CERN-ISOLDE using a Helicon-type plasma ion source (to be published)]: despite its refractory nature, radioactive carbon beams can be produced from molecules (CO or CO2), which can subsequently be broken up and multi-ionized to the required charge state in charge breeders or ECR sources. This contribution will present results of experiments conducted at LPSC with the Phoenix charge breeder and at GANIL with the Nanogan ECR ion source for the ionization of carbon beams in the frame of the ENSAR and EMILIE projects. Carbon is to date the lightest condensable element charge bred with an ECR ion source. Charge breeding efficiencies will be compared with those obtained using Nanogan ECRIS and charge breeding times will be presented as well.

  8. Future carbon beams at SPIRAL1 facility: which method is the most efficient?

    PubMed

    Maunoury, L; Delahaye, P; Angot, J; Dubois, M; Dupuis, M; Frigot, R; Grinyer, J; Jardin, P; Leboucher, C; Lamy, T

    2014-02-01

    Compared to in-flight facilities, Isotope Separator On-Line ones can in principle produce significantly higher radioactive ion beam intensities. On the other hand, they have to cope with delays for the release and ionization which make the production of short-lived isotopes ion beams of reactive and refractory elements particularly difficult. Many efforts are focused on extending the capabilities of ISOL facilities to those challenging beams. In this context, the development of carbon beams is triggering interest [H. Frånberg, M. Ammann, H. W. Gäggeler, and U. Köster, Rev. Sci. Instrum. 77, 03A708 (2006); M. Kronberger, A. Gottberg, T. M. Mendonca, J. P. Ramos, C. Seiffert, P. Suominen, and T. Stora, in Proceedings of the EMIS 2012 [Nucl. Instrum. Methods Phys. Res. B Production of molecular sideband radioisotope beams at CERN-ISOLDE using a Helicon-type plasma ion source (to be published)]: despite its refractory nature, radioactive carbon beams can be produced from molecules (CO or CO2), which can subsequently be broken up and multi-ionized to the required charge state in charge breeders or ECR sources. This contribution will present results of experiments conducted at LPSC with the Phoenix charge breeder and at GANIL with the Nanogan ECR ion source for the ionization of carbon beams in the frame of the ENSAR and EMILIE projects. Carbon is to date the lightest condensable element charge bred with an ECR ion source. Charge breeding efficiencies will be compared with those obtained using Nanogan ECRIS and charge breeding times will be presented as well.

  9. Future carbon beams at SPIRAL1 facility: Which method is the most efficient?

    SciTech Connect

    Maunoury, L. Delahaye, P.; Dubois, M.; Dupuis, M.; Frigot, R.; Grinyer, J.; Jardin, P.; Leboucher, C.

    2014-02-15

    Compared to in-flight facilities, Isotope Separator On-Line ones can in principle produce significantly higher radioactive ion beam intensities. On the other hand, they have to cope with delays for the release and ionization which make the production of short-lived isotopes ion beams of reactive and refractory elements particularly difficult. Many efforts are focused on extending the capabilities of ISOL facilities to those challenging beams. In this context, the development of carbon beams is triggering interest [H. Frånberg, M. Ammann, H. W. Gäggeler, and U. Köster, Rev. Sci. Instrum. 77, 03A708 (2006); M. Kronberger, A. Gottberg, T. M. Mendonca, J. P. Ramos, C. Seiffert, P. Suominen, and T. Stora, in Proceedings of the EMIS 2012 [Nucl. Instrum. Methods Phys. Res. B Production of molecular sideband radioisotope beams at CERN-ISOLDE using a Helicon-type plasma ion source (to be published)]: despite its refractory nature, radioactive carbon beams can be produced from molecules (CO or CO{sub 2}), which can subsequently be broken up and multi-ionized to the required charge state in charge breeders or ECR sources. This contribution will present results of experiments conducted at LPSC with the Phoenix charge breeder and at GANIL with the Nanogan ECR ion source for the ionization of carbon beams in the frame of the ENSAR and EMILIE projects. Carbon is to date the lightest condensable element charge bred with an ECR ion source. Charge breeding efficiencies will be compared with those obtained using Nanogan ECRIS and charge breeding times will be presented as well.

  10. Facile preparation of silver nanoparticle films as an efficient surface-enhanced Raman scattering substrate

    NASA Astrophysics Data System (ADS)

    Sun, Yujing; Zhang, Yue; Shi, Yan; Xiao, Xianping; Dai, Haichao; Hu, Jingting; Ni, Pengjuan; Li, Zhuang

    2013-10-01

    Here, we report a new and facile method to prepare silver nanoparticles (Ag NPs) film for surface-enhanced Raman scattering (SERS)-based sensing. The porous Ni foam was used as a template to generate high quality of Ag NPs by seed-mediated growth of metallic nanoparticles. The preparation process is very economic and environment-friendly, can achieve the recovery of the raw materials. We found that the type of silver-plating solution and the growth time are two key factors to determine the magnitude of SERS signal enhancement. Using rhodamine 6G (R6G) and 4-animothiophenol (4-ATP) as probe molecules, the created Ag NP films exhibited relatively high enhancement ability, good stability, and well reproducibility. The synthesized SERS-active substrate was further used to detect melamine molecules, an illegal additive in infant milk powder, and the limitation of detection can reach 1 μM.

  11. Facile Fabrication of N-Doped Graphene as Efficient Electrocatalyst for Oxygen Reduction Reaction.

    PubMed

    Liao, Yongliang; Gao, Yuan; Zhu, Shenmin; Zheng, Junsheng; Chen, Zhixin; Yin, Chao; Lou, Xianghong; Zhang, Di

    2015-09-01

    A facile bottom-up method is reported here for the fabrication of N-doped graphene for oxygen reduction. It consists of a two-step calcination strategy and uses α-hydroxy acids (AHAs) as carbon source and melamine as nitrogen source. Three different AHAs, malic acid, tartaric acid, and citric acid, were chosen as the carbon sources. The prepared N-doped graphenes have a typical thin layered structure with a large specific surface area. It was found that the N content in the obtained N-doped graphenes varies from 4.12 to 8.11 at. % depending on the AHAs used. All of the samples showed high performance in oxygen reduction reaction (ORR). The N-doped graphene prepared from citric acid demonstrated the highest electrocatalytic activity, which is comparable to the commercial Pt/C and exhibited good durability, attributing to the high pyridinic N content in the composite. PMID:26291928

  12. Uniform, stable, and efficient planar-heterojunction perovskite solar cells by facile low-pressure chemical vapor deposition under fully open-air conditions.

    PubMed

    Luo, Paifeng; Liu, Zhaofan; Xia, Wei; Yuan, Chenchen; Cheng, Jigui; Lu, Yingwei

    2015-02-01

    Recently, hybrid perovskite solar cells (PSCs) have attracted extensive attention due to their high efficiency and simple preparing process. Herein, a facile low-pressure chemical vapor deposition (LPCVD) technology is first developed to fabricate PSCs, which can effectively reduce the over-rapid intercalating reaction rate and easily overcome this blocking issue during the solution process. As a result, the prepared uniform perovskite films exhibit good crystallization, strong absorption, and long carrier diffusion length. More strikingly, CH3NH3PbI3 absorbers by LPCVD demonstrate excellent moisture-resistant feature even under laser illumination and high-temperature conditions, which indicates that our proprietary method is very suitable for the future low-cost, nonvacuum production of the new generation photovoltaic devices. Finally, high efficiency of 12.73% is successfully achieved under fully open-air conditions. To the best of our knowledge, this is the first report of efficient PSCs with such a high humidity above 60%.

  13. Facile synthesis of high surface area molybdenum nitride and carbide

    SciTech Connect

    Roy, Aaron; Serov, Alexey; Artyushkova, Kateryna; Brosha, Eric L.; Atanassov, Plamen; Ward, Tim L.

    2015-08-15

    The synthesis of high surface area γ-Mo{sub 2}N and α-Mo{sub 2}C is reported (116 and 120 m{sup 2}/g) without the temperature programmed reduction of MoO{sub 3}. γ-Mo{sub 2}N was prepared in an NH{sub 3}-free synthesis using forming gas (7 at% H{sub 2}, N{sub 2}-balance) as the reactive atmosphere. Three precursors were studied ((NH{sub 4}){sub 6}Mo{sub 7}O{sub 24}·4H{sub 2}O, (NH{sub 4}){sub 2} Mg(MoO{sub 4}){sub 2}, and MgMoO{sub 4}) along with the sacrificial support method (SSM) as a means of reducing the particle size of Mo{sub 2}N and Mo{sub 2}C. In situ X-ray diffraction (XRD) studies were carried out to identify reaction intermediates, the temperature at which various intermediates form, and the average domain size of the Mo{sub 2}N products. Materials were synthesized in bulk and further characterized by XRD, HRTEM, XPS, and BET. - Highlights: • Facile synthesis of γ-Mo2N and α-Mo2C with surface area exceeding 100 m{sup 2}/g. • Sacrificial support method was used to achieve these high surface areas. • Materials can serve as catalysts or supports in (electro)chemical processes.

  14. High Efficiency, High Density Terrestrial Panel. [for solar cell modules

    NASA Technical Reports Server (NTRS)

    Wohlgemuth, J.; Wihl, M.; Rosenfield, T.

    1979-01-01

    Terrestrial panels were fabricated using rectangular cells. Packing densities in excess of 90% with panel conversion efficiencies greater than 13% were obtained. Higher density panels can be produced on a cost competitive basis with the standard salami panels.

  15. Facile Method To Prepare Microcapsules Inspired by Polyphenol Chemistry for Efficient Enzyme Immobilization.

    PubMed

    Zhang, Shaohua; Jiang, Zhongyi; Wang, Xiaoli; Yang, Chen; Shi, Jiafu

    2015-09-01

    In this study, a method inspired by polyphenol chemistry is developed for the facile preparation of microcapsules under mild conditions. Specifically, the preparation process includes four steps: formation of the sacrificial template, generation of the polyphenol coating on the template surface, cross-linking of the polyphenol coating by cationic polymers, and removal of the template. Tannic acid (TA) is chosen as a representative polyphenol coating precursor for the preparation of microcapsules. The strong interfacial affinity of TA contributes to the formation of polyphenol coating through oxidative oligomerization, while the high reactivity of TA is in charge of reacting/cross-linking with cationic polymer polyethylenimine (PEI) through Schiff base/Michael addition reaction. The chemical/topological structures of the resultant microcapsules are simultaneously characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier Transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), etc. The wall thickness of the microcapsules could be tailored from 257±20 nm to 486±46 nm through changing the TA concentration. The microcapsules are then utilized for encapsulating glucose oxidase (GOD), and the immobilized enzyme exhibits desired catalytic activity and enhanced pH and thermal stabilities. Owing to the structural diversity and functional versatility of polyphenols, this study may offer a facile and generic method to prepare microcapsules and other kinds of functional porous materials.

  16. High efficiency radioisotope thermophotovoltaic prototype generator

    NASA Technical Reports Server (NTRS)

    Avery, James E.; Samaras, John E.; Fraas, Lewis M.; Ewell, Richard

    1995-01-01

    250 Watts of heat input, we expect this prototype to produce over 300 Watts of electrical energy output for a system energy conversion efficiency of over 12%. This low risk, near term design provides advances relative to present radioisotope thermophotovoltaic generators and has the additional advantage of allowing component and system development and testing to begin immediately. Improved cells and filters can easily be incorporated in this baseline system if they should become available in the future.

  17. Biologically inspired highly efficient buoyancy engine

    NASA Astrophysics Data System (ADS)

    Akle, Barbar; Habchi, Wassim; Abdelnour, Rita; Blottman, John, III; Leo, Donald

    2012-04-01

    Undersea distributed networked sensor systems require a miniaturization of platforms and a means of both spatial and temporal persistence. One aspect of this system is the necessity to modulate sensor depth for optimal positioning and station-keeping. Current approaches involve pneumatic bladders or electrolysis; both require mechanical subsystems and consume significant power. These are not suitable for the miniaturization of sensor platforms. Presented in this study is a novel biologically inspired method that relies on ionic motion and osmotic pressures to displace a volume of water from the ocean into and out of the proposed buoyancy engine. At a constant device volume, the displaced water will alter buoyancy leading to either sinking or floating. The engine is composed of an enclosure sided on the ocean's end by a Nafion ionomer and by a flexible membrane separating the water from a gas enclosure. Two electrodes are placed one inside the enclosure and the other attached to the engine on the outside. The semi-permeable membrane Nafion allows water motion in and out of the enclosure while blocking anions from being transferred. The two electrodes generate local concentration changes of ions upon the application of an electrical field; these changes lead to osmotic pressures and hence the transfer of water through the semi-permeable membrane. Some aquatic organisms such as pelagic crustacean perform this buoyancy control using an exchange of ions through their tissue to modulate its density relative to the ambient sea water. In this paper, the authors provide an experimental proof of concept of this buoyancy engine. The efficiency of changing the engine's buoyancy is calculated and optimized as a function of electrode surface area. For example electrodes made of a 3mm diameter Ag/AgCl proved to transfer approximately 4mm3 of water consuming 4 Joules of electrical energy. The speed of displacement is optimized as a function of the surface area of the Nafion

  18. High efficiency radioisotope thermophotovoltaic prototype generator

    NASA Astrophysics Data System (ADS)

    Avery, James E.; Samaras, John E.; Fraas, Lewis M.; Ewell, Richard

    1995-10-01

    250 Watts of heat input, we expect this prototype to produce over 300 Watts of electrical energy output for a system energy conversion efficiency of over 12%. This low risk, near term design provides advances relative to present radioisotope thermophotovoltaic generators and has the additional advantage of allowing component and system development and testing to begin immediately. Improved cells and filters can easily be incorporated in this baseline system if they should become available in the future.

  19. High efficiency low cost GaAs/Ge cell technology

    NASA Technical Reports Server (NTRS)

    Ho, Frank

    1990-01-01

    Viewgraphs on high efficiency low cost GaAs/Ge cell technology are presented. Topics covered include: high efficiency, low cost GaAs/Ge solar cells; advantages of Ge; comparison of typical production cells for space applications; panel level comparisons; and solar cell technology trends.

  20. Vacuum testing of high efficiency AMTEC cells

    SciTech Connect

    Schuller, M.; Phillips, P.H.; Reiners, E.; Merrill, J.; Crowley, C.; Izenson, M.

    1996-12-31

    The Phillips Laboratory Power and Thermal Management Division (PL/VTP), in cooperation with JPL, AMPS, Creare, and ORION, is performing vacuum testing of high performance Alkali Metal Thermal to Electric Conversion (AMTEC) cells, including the Micro-Machined Evaporator (MME) and PL-9A cells. The MME cell was designed to test an improved evaporator, which should allow long term operation at evaporator temperatures as high as 1,100 K. The PL-9A cell was designed and built by AMPS under contract to ORION to test an improved heat shield assembly. The testing at Phillips Lab is done in a vacuum test stand which simulates the environment of an AMTEC cell operating as part of a spacecraft power system. The test configuration consists of the MME cell (later replaced by by the PL-9A cell) in the center of an array of six other AMTEC cells. The seven cells are encased in multifoil insulation. Testing shows that there is little difference between cell current/voltage performance when measured in vacuum tests compared to guard heater tests. The author are also examining the differences between fast I-V curve sweeps, recorded manually, with the cell operating at constant heat input, over a period of five minutes or less, and equilibrium I-V curve sweeps, in which the cell reaches thermal equilibrium at each data point.

  1. TLD efficiency of 7LiF for doses deposited by high-LET particles

    NASA Technical Reports Server (NTRS)

    Benton, E. R.; Frank, A. L.; Benton, E. V.

    2000-01-01

    The efficiency of 7 LiF TLDs (TLD-700) in registering dose from high-LET (> or = 10 keV/micrometers) charged particles (relative to 137Cs gamma rays) has been measured for a number of accelerated heavy ions at various particle accelerator facilities. These measured efficiency values have been compared with similar results obtained from the open literature and a dose efficiency function has been fitted to the combined data set. While it was found that the dose efficiency is not only a function of LET, but also of the charge of the incident particle, the fitted function can be used to correct the undermeasured value of dose from exposures made in mixed radiation fields where LET information is available. This LET-dependent dose efficiency function is used in our laboratory in determining total absorbed dose and dose equivalent from combined TLD and CR-39 plastic nuclear track detector measurements.

  2. Compact and highly efficient laser pump cavity

    DOEpatents

    Chang, Jim J.; Bass, Isaac L.; Zapata, Luis E.

    1999-01-01

    A new, compact, side-pumped laser pump cavity design which uses non-conventional optics for injection of laser-diode light into a laser pump chamber includes a plurality of elongated light concentration channels. In one embodiment, the light concentration channels are compound parabolic concentrators (CPC) which have very small exit apertures so that light will not escape from the pumping chamber and will be multiply reflected through the laser rod. This new design effectively traps the pump radiation inside the pump chamber that encloses the laser rod. It enables more uniform laser pumping and highly effective recycle of pump radiation, leading to significantly improved laser performance. This new design also effectively widens the acceptable radiation wavelength of the diodes, resulting in a more reliable laser performance with lower cost.

  3. A facile and efficient transposon mutagenesis method for generation of multi-codon deletions in protein sequences.

    PubMed

    Liu, Shu-Su; Wei, Xuan; Ji, Qun; Xin, Xiu; Jiang, Biao; Liu, Jia

    2016-06-10

    Substitutions, insertions and deletions are all important mutation events in natural and laboratory protein evolution. However, protein engineering using insertions and deletions (indels) is hindered by the lack of a convenient mutagenesis method. Here, we describe a general transposon mutagenesis method that allows for removal of up to five consecutive in-frame codons from a random position of a target protein. This method, referred to as codon deletion mutagenesis (CDM), relies on an engineered Mu transposon that carries asymmetric terminal sequences flanking the MuA transposase recognition sites. CDM requires minimal DNA manipulations, and can generate multi-codon deletions with high efficiency (>90%). As a proof of principle, we constructed five libraries of green fluorescent protein (GFP) containing one to five random codon deletions, respectively. Several variants with multi-codon deletions remained fluorescent, none of which could be easily identified using traditional mutagenesis method. CDM provides a facile and efficient approach to sampling a protein sequence with multi-codon deletions. It will not only facilitate our understanding of the effects of amino acid deletions on protein function but also expedite protein engineering using deletion mutagenesis. PMID:27071724

  4. High Performance Computing Facility Operational Assessment, FY 2011 Oak Ridge Leadership Computing Facility

    SciTech Connect

    Baker, Ann E; Bland, Arthur S Buddy; Hack, James J; Barker, Ashley D; Boudwin, Kathlyn J.; Kendall, Ricky A; Messer, Bronson; Rogers, James H; Shipman, Galen M; Wells, Jack C; White, Julia C

    2011-08-01

    Oak Ridge National Laboratory's Leadership Computing Facility (OLCF) continues to deliver the most powerful resources in the U.S. for open science. At 2.33 petaflops peak performance, the Cray XT Jaguar delivered more than 1.5 billion core hours in calendar year (CY) 2010 to researchers around the world for computational simulations relevant to national and energy security; advancing the frontiers of knowledge in physical sciences and areas of biological, medical, environmental, and computer sciences; and providing world-class research facilities for the nation's science enterprise. Scientific achievements by OLCF users range from collaboration with university experimentalists to produce a working supercapacitor that uses atom-thick sheets of carbon materials to finely determining the resolution requirements for simulations of coal gasifiers and their components, thus laying the foundation for development of commercial-scale gasifiers. OLCF users are pushing the boundaries with software applications sustaining more than one petaflop of performance in the quest to illuminate the fundamental nature of electronic devices. Other teams of researchers are working to resolve predictive capabilities of climate models, to refine and validate genome sequencing, and to explore the most fundamental materials in nature - quarks and gluons - and their unique properties. Details of these scientific endeavors - not possible without access to leadership-class computing resources - are detailed in Section 4 of this report and in the INCITE in Review. Effective operations of the OLCF play a key role in the scientific missions and accomplishments of its users. This Operational Assessment Report (OAR) will delineate the policies, procedures, and innovations implemented by the OLCF to continue delivering a petaflop-scale resource for cutting-edge research. The 2010 operational assessment of the OLCF yielded recommendations that have been addressed (Reference Section 1) and where

  5. 2250-MHz High Efficiency Microwave Power Amplifier (HEMPA)

    NASA Technical Reports Server (NTRS)

    Sims, W. Herbert; Bell, Joseph L. (Technical Monitor)

    2001-01-01

    Tnis paper will focus on developing an exotic switching technique that enhances the DC-to-RF conversion efficiency of microwave power amplifiers. For years, switching techniques implemented in the 10 kHz to 30 MHz region have resulted in DC-to-RF conversion efficiencies of 90-95-percent. Currently amplifier conversion efficiency, in the 2-3 GHz region approaches, 10-20-percent. Using a combination of analytical modeling and hardware testing, a High Efficiency Microwave Power Amplifier was built that demonstrated conversion efficiencies four to five times higher than current state of the art.

  6. Does High School Facility Quality Affect Student Achievement? A Two-Level Hierarchical Linear Model

    ERIC Educational Resources Information Center

    Bowers, Alex J.; Urick, Angela

    2011-01-01

    The purpose of this study is to isolate the independent effects of high school facility quality on student achievement using a large, nationally representative U.S. database of student achievement and school facility quality. Prior research on linking school facility quality to student achievement has been mixed. Studies that relate overall…

  7. The Grizzly Powerhouse: A modern high-head hydrogenerating facility

    SciTech Connect

    Siebensohn, F.B.

    1995-12-31

    With the emphasis on the modernization of existing plants, there are not all that many new hydropower stations being built nowadays. A noteworthy exception from this trend is the Grizzly Powerhouse, located in the High Sierra near Quincy in northern California. This new $75 million facility is an addition to the existing 65 MW Bucks Creek hydroelectric project on the North Fork Feather River watershed in Plumas County, that is owned and operated by Pacific Gas and Electric Company. The Grizzly project is a cooperative development between Pacific Gas and Electric and the City of Santa Clara. The City paid for the powerhouse and will receive its electricity for at least 30 years. Pacific Gas and Electric has an option to buy the Grizzly project thereafter. The energy generated serves about 15,000 homes in Santa Clara and meets approximately seven percent of the City`s current peak power needs. AMERICAN HYDRO CORPORATION of York, Pennsylvania was the Prime Contractor for the supply of the power generation equipment, and as such was responsible for the performance of the system components. These included the turbine with the inlet/shut-off valve, the pressure relief valve, the governor and the generator with its excitation system.

  8. Energy efficient engine high-pressure turbine detailed design report

    NASA Technical Reports Server (NTRS)

    Thulin, R. D.; Howe, D. C.; Singer, I. D.

    1982-01-01

    The energy efficient engine high-pressure turbine is a single stage system based on technology advancements in the areas of aerodynamics, structures and materials to achieve high performance, low operating economics and durability commensurate with commercial service requirements. Low loss performance features combined with a low through-flow velocity approach results in a predicted efficiency of 88.8 for a flight propulsion system. Turbine airfoil durability goals are achieved through the use of advanced high-strength and high-temperature capability single crystal materials and effective cooling management. Overall, this design reflects a considerable extension in turbine technology that is applicable to future, energy efficient gas-turbine engines.

  9. Description of high-occupancy-vehicle facilities in North America. Technical report

    SciTech Connect

    Turnbull, K.F.; Hanks, J.W.

    1990-07-01

    The report presents a description of existing high-occupancy vehicle (HOV) facilities in operation either on freeways or in separate rights-of-way in North America. Up-to-date information is provided on the design, operations, enforcement characteristics, and current utilization rates for 40 HOV facilities in 20 metropolitan areas. The report includes general descriptions of each facility, maps showing the location of each facility, representative cross-sections and a series of tables containing detailed information in each project.

  10. On-shot laser beam diagnostics for high-power laser facility with phase modulation imaging

    NASA Astrophysics Data System (ADS)

    Pan, X.; Veetil, S. P.; Liu, C.; Tao, H.; Jiang, Y.; Lin, Q.; Li, X.; Zhu, J.

    2016-05-01

    A coherent-modulation-imaging-based (CMI) algorithm has been employed for on-shot laser beam diagnostics in high-power laser facilities, where high-intensity short-pulsed lasers from terawatt to petawatt are designed to realize inertial confinement fusion (ICF). A single-shot intensity measurement is sufficient for wave-front reconstruction, both for the near-field and far-field at the same time. The iterative reconstruction process is computationally very efficient and was completed in dozens of seconds by the additional use of a GPU device to speed it up. The compact measurement unit—including a CCD and a piece of pre-characterized phase plate—makes it convenient for focal-spot intensity prediction in the target chamber. It can be placed almost anywhere in high-power laser facilities to achieve near-field wave-front diagnostics. The feasibility of the method has been demonstrated by conducting a series of experiments with diagnostic beams and seed pulses with deactivated amplifiers in our high-power laser system.

  11. A facile one-step solution deposition via non-solvent/solvent mixture for efficient organometal halide perovskite light-emitting diodes.

    PubMed

    Jiao, Bo; Zhu, Xiaobo; Wu, Wen; Dong, Hua; Xia, Bin; Xi, Jun; Lei, Ting; Hou, Xun; Wu, Zhaoxin

    2016-06-01

    Although organometal halide perovskite materials have shown great potential in light-emitting diodes, their performance is greatly restricted by the poor morphology of the perovskite layer. In this work, we demonstrate a facile one-step solution method to improve the perovskite film morphology via a non-solvent/solvent mixture. An efficient CH3NH3PbBr3-based light-emitting diode was prepared with a chlorobenzene/N,N-dimethylformamide mixed solvent. A high efficiency of 0.54 cd A(-1) is demonstrated, which is 22 times higher than that of a device fabricated by a traditional one-step solution process. Furthermore, the uniformity of the emission region and the device stability are strongly improved by this facile one-step solution process. Our work paves a new way for the morphological control of perovskite films for application in light-emitting diodes.

  12. Highlighting High Performance: The Solar Energy Research Facility, Golden, Colorado

    SciTech Connect

    2001-06-01

    The Solar Energy Research Facility uses a stair-step configuration to allow daylight and heat into the office areas, while the laboratories in the back of the building are in a more controlled environment.

  13. High efficiency in human muscle: an anomaly and an opportunity?

    PubMed Central

    Nelson, Frank E.; Ortega, Justus D.; Jubrias, Sharon A.; Conley, Kevin E.; Kushmerick, Martin J.

    2011-01-01

    Summary Can human muscle be highly efficient in vivo? Animal muscles typically show contraction-coupling efficiencies <50% in vitro but a recent study reports that the human first dorsal interosseous (FDI) muscle of the hand has an efficiency value in vivo of 68%. We examine two key factors that could account for this apparently high efficiency value: (1) transfer of cross-bridge work into mechanical work and (2) the use of elastic energy to do external work. Our analysis supports a high contractile efficiency reflective of nearly complete transfer of muscular to mechanical work with no contribution by recycling of elastic energy to mechanical work. Our survey of reported contraction-coupling efficiency values puts the FDI value higher than typical values found in small animals in vitro but within the range of values for human muscle in vivo. These high efficiency values support recent studies that suggest lower Ca2+ cycling costs in working contractions and a decline in cost during repeated contractions. In the end, our analysis indicates that the FDI muscle may be exceptional in having an efficiency value on the higher end of that reported for human muscle. Thus, the FDI muscle may be an exception both in contraction-coupling efficiency and in Ca2+ cycling costs, which makes it an ideal muscle model system offering prime conditions for studying the energetics of muscle contraction in vivo. PMID:21795559

  14. High efficiency in human muscle: an anomaly and an opportunity?

    PubMed

    Nelson, Frank E; Ortega, Justus D; Jubrias, Sharon A; Conley, Kevin E; Kushmerick, Martin J

    2011-08-15

    Can human muscle be highly efficient in vivo? Animal muscles typically show contraction-coupling efficiencies <50% in vitro but a recent study reports that the human first dorsal interosseous (FDI) muscle of the hand has an efficiency value in vivo of 68%. We examine two key factors that could account for this apparently high efficiency value: (1) transfer of cross-bridge work into mechanical work and (2) the use of elastic energy to do external work. Our analysis supports a high contractile efficiency reflective of nearly complete transfer of muscular to mechanical work with no contribution by recycling of elastic energy to mechanical work. Our survey of reported contraction-coupling efficiency values puts the FDI value higher than typical values found in small animals in vitro but within the range of values for human muscle in vivo. These high efficiency values support recent studies that suggest lower Ca(2+) cycling costs in working contractions and a decline in cost during repeated contractions. In the end, our analysis indicates that the FDI muscle may be exceptional in having an efficiency value on the higher end of that reported for human muscle. Thus, the FDI muscle may be an exception both in contraction-coupling efficiency and in Ca(2+) cycling costs, which makes it an ideal muscle model system offering prime conditions for studying the energetics of muscle contraction in vivo.

  15. High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency

    SciTech Connect

    Singer, Brett C.; Tschudi, William F.

    2009-09-08

    This document presents a road map for improving the energy efficiency of hospitals and other healthcare facilities. The report compiles input from a broad array of experts in healthcare facility design and operations. The initial section lists challenges and barriers to efficiency improvements in healthcare. Opportunities are organized around the following ten themes: understanding and benchmarking energy use; best practices and training; codes and standards; improved utilization of existing HVAC designs and technology; innovation in HVAC design and technology; electrical system design; lighting; medical equipment and process loads; economic and organizational issues; and the design of next generation sustainable hospitals. Achieving energy efficiency will require a broad set of activities including research, development, deployment, demonstration, training, etc., organized around 48 specific objectives. Specific activities are prioritized in consideration of potential impact, likelihood of near- or mid-term feasibility and anticipated cost-effectiveness. This document is intended to be broad in consideration though not exhaustive. Opportunities and needs are identified and described with the goal of focusing efforts and resources.

  16. Copper-Based Ultrathin Nickel Nanocone Films with High-Efficiency Dropwise Condensation Heat Transfer Performance.

    PubMed

    Zhao, Ye; Luo, Yuting; Zhu, Jie; Li, Juan; Gao, Xuefeng

    2015-06-10

    We report a type of copper-based ultrathin nickel nanocone films with high-efficiency dropwise condensation heat transfer (DCHT) performance, which can be fabricated by facile electrodeposition and low-surface-energy chemistry modification. Compared with flat copper samples, our nanosamples show condensate microdrop self-propelling (CMDSP) function and over 89% enhancement in the DCHT coefficient. Such remarkable enhancement may be ascribed to the cooperation of surface nanostructure-induced CMDSP function as well as in situ integration and ultrathin nature of nanofilms. These findings are very significant to design and develop advanced DCHT materials and devices, which help improve the efficiency of thermal management and energy utilization.

  17. High efficiency IMPATT diodes for 60 GHz intersatellite link applications

    NASA Technical Reports Server (NTRS)

    Haugland, E. J.

    1984-01-01

    Intersatellite links are expected to play an increasingly important role in future satellite systems. Improved components are required to properly utilize the wide bandwidth allocated for intersatellite link applications around 60 GHz. IMPATT diodes offer the highest potential performance as solid state power sources for a 60 GHz transmitter. Presently available devices do not have the desired power and efficiency. High efficiency, high power IMPATT diodes for intersatellite link applications are being developed by NASA and other government agencies. The development of high efficiency 60 GHz IMPATT diodes by NASA is described.

  18. Summary of efficiency testing of standard and high-capacity high-efficiency particulate air filters subjected to simulated tornado depressurization and explosive shock waves

    SciTech Connect

    Smith, P.R.; Gregory, W.S.

    1985-04-01

    Pressure transients in nuclear facility air cleaning systems can originate from natural phenomena such as tornadoes or from accident-induced explosive blast waves. This study was concerned with the effective efficiency of high-efficiency particulate air (HEPA) filters during pressure surges resulting from simulated tornado and explosion transients. The primary objective of the study was to examine filter efficiencies at pressure levels below the point of structural failure. Both standard and high-capacity 0.61-m by 0.61-m HEPA filters were evaluated, as were several 0.2-m by 0.2-m HEPA filters. For a particular manufacturer, the material release when subjected to tornado transients is the same (per unit area) for both the 0.2-m by 0.2-m and the 0.61-m by 0.61-m filters. For tornado transients, the material release was on the order of micrograms per square meter. When subjecting clean HEPA filters to simulated tornado transients with aerosol entrained in the pressure pulse, all filters tested showed a degradation of filter efficiency. For explosive transients, the material release from preloaded high-capacity filters was as much as 340 g. When preloaded high-capacity filters were subjected to shock waves approximately 50% of the structural limit level, 1 to 2 mg of particulate was released.

  19. Development of an Improved High Efficiency Thin Solar Cell

    NASA Technical Reports Server (NTRS)

    Lindmayer, J.; Wrigley, C.; Storti, G.

    1979-01-01

    High efficiency cells (up to 14 AMO at 25 C)were fabricated from 10 - 15 ohm-cm silicon by using screen printed aluminum paste as the alloy source for the production of back surface fields. Thick consistency pastes that have been cured prior to a short heat treatment at 850 C were most effective in achieving these efficiency levels.

  20. Efficient High Performance Collective Communication for Distributed Memory Environments

    ERIC Educational Resources Information Center

    Ali, Qasim

    2009-01-01

    Collective communication allows efficient communication and synchronization among a collection of processes, unlike point-to-point communication that only involves a pair of communicating processes. Achieving high performance for both kernels and full-scale applications running on a distributed memory system requires an efficient implementation of…

  1. High efficiency hydrocarbon-free resonance transition potassium laser

    NASA Astrophysics Data System (ADS)

    Zweiback, Jason; Hager, Gordon; Krupke, William F.

    2009-05-01

    We experimentally demonstrate a high efficiency potassium laser using a 0.15 nm bandwidth alexandrite laser as the pump source. The laser uses naturally occurring helium as the buffer gas. We achieve a 64% slope efficiency and a 57% optical to optical conversion. A pulsed laser model shows good agreement with the data.

  2. A highly efficient neutron time-of-flight detector for inertial confinement fusion experiments

    NASA Astrophysics Data System (ADS)

    Izumi, N.; Yamaguchi, K.; Yamagajo, T.; Nakano, T.; Kasai, T.; Urano, T.; Azechi, H.; Nakai, S.; Iida, T.

    1999-01-01

    We have developed the highly efficient neutron detector system MANDALA for the inertial-confinement-fusion experiment. The MANDALA system consists of 842 elements plastic scintillation detectors and data acquisition electronics. The detection level is the yield of 1.2×105 for 2.5 MeV and 1×105 for 14.1 MeV neutrons (with 100 detected hits). We have calibrated the intrinsic detection efficiencies of the detector elements using a neutron generator facility. Timing calibration and integrity test of the system were also carried out with a 60Co γ ray source. MANDALA system was applied to the implosion experiments at the GEKKO XII laser facility. The integrity test was carried out by implosion experiments.

  3. Efficient cytosolic delivery mediated by polymersomes facilely prepared from a degradable, amphiphilic, and amphoteric copolymer

    NASA Astrophysics Data System (ADS)

    Huang, Zhonghui; Teng, Wei; Liu, Longshan; Wang, Lichun; Wang, Qinmei; Dong, Yugang

    2013-07-01

    To solve problems in polymersome preparation caused by liposolubility of copolymers and to improve the cytosolic delivery efficiency of polymersomes to drugs, a lipopolysaccharide-amine (LPSA) copolymer with amphotericity and amphiphilicity is developed. LPSA contains two hydrophilic oppositely charged blocks (anionic oxidized alginate (OA), cationic polyethyleneimine (PEI 1.8k)) and one hydrophobic block (cholesteryl), where OA is the backbone and cholesteryl-grafted PEI is the side chain. The two hydrophilic blocks first guarantee that LPSA will dissolve in water, and then help polymersome formation via electrostatic interactions to generate water insoluble interpolyelectrolyte complexes, which supplement the hydrophobic part to reach the right hydrophilicity/hydrophobicity ratio, and thus realize a one-step self-assembly of polymersomes in water. Our results show LPSA nanopolymersomes (LNPs) have low cytotoxicity and degradability, and an excellent ability to enter cells. TEM observation demonstrates that LNPs are entrapped in endosomes after endocytosis, and are then released to cytosols because of their strong endosomal escape capacity. As an example of cytosolic delivery to bioactive molecules, pDNA is delivered in mesenchymal stem cells, and more than 95% of cells express a large target protein, indicating that LNPs have high cytosolic delivery efficiency. Our study provides a novel, easy, and universal method to design copolymers for the preparation of polymersomes as efficient cytosolic delivery nanocarriers.

  4. Chemical Entity Semantic Specification: Knowledge representation for efficient semantic cheminformatics and facile data integration

    PubMed Central

    2011-01-01

    Background Over the past several centuries, chemistry has permeated virtually every facet of human lifestyle, enriching fields as diverse as medicine, agriculture, manufacturing, warfare, and electronics, among numerous others. Unfortunately, application-specific, incompatible chemical information formats and representation strategies have emerged as a result of such diverse adoption of chemistry. Although a number of efforts have been dedicated to unifying the computational representation of chemical information, disparities between the various chemical databases still persist and stand in the way of cross-domain, interdisciplinary investigations. Through a common syntax and formal semantics, Semantic Web technology offers the ability to accurately represent, integrate, reason about and query across diverse chemical information. Results Here we specify and implement the Chemical Entity Semantic Specification (CHESS) for the representation of polyatomic chemical entities, their substructures, bonds, atoms, and reactions using Semantic Web technologies. CHESS provides means to capture aspects of their corresponding chemical descriptors, connectivity, functional composition, and geometric structure while specifying mechanisms for data provenance. We demonstrate that using our readily extensible specification, it is possible to efficiently integrate multiple disparate chemical data sources, while retaining appropriate correspondence of chemical descriptors, with very little additional effort. We demonstrate the impact of some of our representational decisions on the performance of chemically-aware knowledgebase searching and rudimentary reaction candidate selection. Finally, we provide access to the tools necessary to carry out chemical entity encoding in CHESS, along with a sample knowledgebase. Conclusions By harnessing the power of Semantic Web technologies with CHESS, it is possible to provide a means of facile cross-domain chemical knowledge integration with full

  5. Facile mesoporous template-assisted hydrothermal synthesis of ordered mesoporous magnesium silicate as an efficient adsorbent

    NASA Astrophysics Data System (ADS)

    Lu, Qingshan; Li, Qiang; Zhang, Jingjing; Li, Jingfeng; Lu, Jinhua

    2016-01-01

    Mesoporous materials with unique structure as well as special morphology have potential applications in pollutant adsorption. In this work, using mesoporous silica SBA-15 filled with carbon (C@SBA-15) as both silicon source and assisted template, the ordered mesoporous magnesium silicate (Mg3Si4O9(OH)4) has been fabricated at 140 °C by a novel and facile hydrothermal method. During the hydrothermal process, the magnesium silicate grew along the silica walls at the expense of consuming silica and deposited on the carbon surface of the C@SBA-15. Meanwhile, the rigid carbon inside the pores of the SBA-15 supported the magnesium silicate as mesoporous walls under hydrothermal condition. The obtained magnesium silicate possessed ordered mesoporous structure, high specific surface area of 446 m2/g, large pore volume of 0.84 cm3/g, and hierarchical structure assembled with ultrathin nanosheets of 15 nm in thickness. These characteristics endow the ordered mesoporous magnesium silicate with the fast adsorption rate and high adsorption capacity of 382 mg/g for methylene blue. In addition, this synthesis method opens a new approach to fabricate other ordered mesoporous silicates.

  6. A high temperature fatigue and structures testing facility

    NASA Technical Reports Server (NTRS)

    Bartolotta, Paul A.; Mcgaw, Michael A.

    1987-01-01

    As man strives for higher levels of sophistication in air and space transportation, awareness of the need for accurate life and material behavior predictions for advanced propulsion system components is heightened. Such sophistication will require complex operating conditions and advanced materials to meet goals in performance, thrust-to-weight ratio, and fuel efficiency. To accomplish these goals will require that components be designed using a high percentage of the material's ultimate capabilities. This serves only to complicate matters dealing with life and material behavior predictions. An essential component of material behavior model development is the underlying experimentation which must occur to identify phenomena. To support experimentation, the NASA Lewis Research Center's High Temperature Fatigue and Structures Laboratory has been expanded significantly. Several new materials testing systems have been added, as well as an extensive computer system. The intent of this paper is to present an overview of the laboratory, and to discuss specific aspects of the test systems. A limited discussion of computer capabilities will also be presented.

  7. Laser driven nuclear science and applications: The need of high efficiency, high power and high repetition rate Laser beams

    NASA Astrophysics Data System (ADS)

    Gales, S.

    2015-10-01

    Extreme Light Infrastructure (ELI) is a pan European research initiative selected on the European Strategy Forum on Research Infrastructures Roadmap that aims to close the gap between the existing laboratory-based laser driven research and international facility-grade research centre. The ELI-NP facility, one of the three ELI pillars under construction, placed in Romania and to be operational in 2018, has as core elements a couple of new generation 10 PW laser systems and a narrow bandwidth Compton backscattering gamma source with photon energies up to 19 MeV. ELI-NP will address nuclear photonics, nuclear astrophysics and quantum electrodynamics involving extreme photon fields. Prospective applications of high power laser in nuclear astrophysics, accelerator physics, in particular towards future Accelerator Driven System, as well as in nuclear photonics, for detection and characterization of nuclear material, and for nuclear medicine, will be discussed. Key issues in these research areas will be at reach with significant increase of the repetition rates and of the efficiency at the plug of the high power laser systems as proposed by the ICAN collaboration.

  8. Regenerative fuel cell combines high efficiency with low cost

    NASA Technical Reports Server (NTRS)

    Doyle, H.; Frank, H.; Stephens, C. W.

    1965-01-01

    Hydrogen/oxygen regenerative fuel cell stores electrical energy efficiently and inexpensively. The fuel cell has a high energy-to-weight ratio, and is adapted for a large number of cycles with deep discharge.

  9. III-V High-Efficiency Multijunction Photovoltaics (Fact Sheet)

    SciTech Connect

    Not Available

    2011-06-01

    Capabilities fact sheet that includes scope, core competencies and capabilities, and contact/web information for III-V High-Efficiency Multijunction Photovoltaics at the National Center for Photovoltaics.

  10. Development of high-efficiency solar cells on silicon web

    NASA Technical Reports Server (NTRS)

    Rohatgi, A.; Meier, D. L.; Campbell, R. B.; Seidensticker, R. G.; Rai-Choudhury, P.

    1984-01-01

    The development of high efficiency solar cells on a silicon web is discussed. Heat treatment effects on web quality; the influence of twin plane lamellae, trace impurities and stress on minority carrier lifetime; and the fabrication of cells are discussed.

  11. High efficiency solar cell research for space applications

    NASA Technical Reports Server (NTRS)

    Flood, D. J.

    1985-01-01

    A review is given of NASA photovoltaic research with emphasis on the activities of the Lewis Research Center. High efficiency solar cell research is discussed, as well as solar arrays, multi-junction cell bandgaps, and plasmon coupling.

  12. High efficiency multichannel collimator for structural studies of liquids and low-Z materials at high pressures and temperatures.

    PubMed

    Morard, G; Mezouar, M; Bauchau, S; Álvarez-Murga, M; Hodeau, J-L; Garbarino, G

    2011-02-01

    A high efficiency multichannel collimator (MCC) device has been developed at the high pressure beamline ID27 of the European Synchrotron Radiation Facility to drastically reduce the x-ray background from the sample environment in the Paris-Edinburgh press. The main technical difficulty, which resides in the minimum slits size achievable using the classical mono-bloc design, has been resolved using an original concept based on a set of independent slits. Then, a very small slit size of 50 μm was manufactured resulting in a great improvement of the signal to background ratio. In addition, the transfer function of the MCC has been measured using the x-ray diffusion signal of a metal doped glass and efficiently applied to correct the raw data. The potential of this new device is illustrated in two challenging examples: iron-sulfur liquid structures and C(60) polymerization process at high pressure and high temperature.

  13. High efficiency multichannel collimator for structural studies of liquids and low-Z materials at high pressures and temperatures

    SciTech Connect

    Morard, G.; Mezouar, M.; Bauchau, S.; Garbarino, G.; Alvarez-Murga, M.; Hodeau, J.-L.

    2011-02-15

    A high efficiency multichannel collimator (MCC) device has been developed at the high pressure beamline ID27 of the European Synchrotron Radiation Facility to drastically reduce the x-ray background from the sample environment in the Paris-Edinburgh press. The main technical difficulty, which resides in the minimum slits size achievable using the classical mono-bloc design, has been resolved using an original concept based on a set of independent slits. Then, a very small slit size of 50 {mu}m was manufactured resulting in a great improvement of the signal to background ratio. In addition, the transfer function of the MCC has been measured using the x-ray diffusion signal of a metal doped glass and efficiently applied to correct the raw data. The potential of this new device is illustrated in two challenging examples: iron-sulfur liquid structures and C{sub 60} polymerization process at high pressure and high temperature.

  14. Global climate change: Mitigation opportunities high efficiency large chiller technology

    SciTech Connect

    Stanga, M.V.

    1997-12-31

    This paper, comprised of presentation viewgraphs, examines the impact of high efficiency large chiller technology on world electricity consumption and carbon dioxide emissions. Background data are summarized, and sample calculations are presented. Calculations show that presently available high energy efficiency chiller technology has the ability to substantially reduce energy consumption from large chillers. If this technology is widely implemented on a global basis, it could reduce carbon dioxide emissions by 65 million tons by 2010.

  15. Energy efficient engine: High pressure turbine uncooled rig technology report

    NASA Technical Reports Server (NTRS)

    Gardner, W. B.

    1979-01-01

    Results obtained from testing five performance builds (three vane cascades and two rotating rigs of the Energy Efficient Engine uncooled rig have established the uncooled aerodynamic efficiency of the high-pressure turbine at 91.1 percent. This efficiency level was attained by increasing the rim speed and annulus area (AN(2)), and by increasing the turbine reaction level. The increase in AN(2) resulted in a performance improvement of 1.15 percent. At the design point pressure ratio, the increased reaction level rig demonstrated an efficiency of 91.1 percent. The results of this program have verified the aerodynamic design assumptions established for the Energy Efficient Engine high-pressure turbine component.

  16. High-efficiency silicon concentrator solar cell research

    NASA Astrophysics Data System (ADS)

    Greene, M. A.; Blakers, A. W.; Zhao, Jianhua; Wang, Ahua; Milne, A. M.; Ximing, Dai; Chong, C. M.

    1989-12-01

    This project continued the development of high efficiency silicon concentrator solar cells with the goal of achieving a 24% efficient module ready cell. This target was comfortably achieved with efficiencies as high as 25.2% at 125 suns concentration measured at Sandia National Laboratories. In outdoor testing at Sandia, cells of this type but of more modest performance resulted in lens/cell efficiency above 20% for the first time. Exciting results were obtained with a new cell structure, the PERC cell (passivated emitter and rear cell) which demonstrated an efficiency of 21.8% for a nonconcentrating cell and creditable performance out to 20 suns for concentrator cells. Progress was also reported for cells fabricated on n-type substrates and for plasma grooved, buried contact solar cells.

  17. High-efficiency silicon concentrator solar cell research

    SciTech Connect

    Green, M.A.; Blakers, A.W.; Jianhua, Zhao; Aihua, Wang; Milne, A.M.; Dai, Ximing; Chong, C.M. . Solar Photovoltaic Lab.)

    1989-12-01

    This project continued the development of high efficiency silicon concentrator solar cells with the goal of achieving a 24% efficient module ready'' cell. This target was comfortably achieved with efficiencies as high as 25.2% at 125 suns concentration measured at Sandia National Laboratories. In outdoor testing at Sandia, cells of this type but of more modest performance resulted in lens/cell efficiency above 20% for the first time. Exciting results were obtained with a new cell structure, the PERC cell (passivated emitter and rear cell) which demonstrated an efficiency of 21.8% for a nonconcentrating cell and creditable performance out to 20 suns for concentrator cells. Progress was also reported for cells fabricated on n-type substrates and for plasma grooved, buried contact solar cells. 22 refs., 23 figs., 9 tabs.

  18. Power Systems Development Facility: High Temperature, High Pressure Filtration in Gasification Operation

    SciTech Connect

    Martin, R.A.; Guan, X.; Gardner, B.; Hendrix, H.

    2002-09-18

    High temperature, high pressure gas filtration is a fundamental component of several advanced coal-fired power systems. This paper discusses the hot-gas filter vessel operation in coal gasification mode at the Power Systems Development Facility (PSDF). The PSDF, near Wilsonville, Alabama, is funded by the U.S. Department of Energy (DOE), Southern Company, and other industrial participants currently including the Electric Power Research Institute, Siemens Westinghouse Power Corporation, Kellogg Brown & Root Inc. (KBR), and Peabody Energy. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems designed at sufficient size to provide data for commercial scale-up.

  19. N-231 High Reynolds Number Channel I is a blowdown Facility that utilizes interchangeable test

    NASA Technical Reports Server (NTRS)

    1980-01-01

    N-231 High Reynolds Number Channel I is a blowdown Facility that utilizes interchangeable test sections and nozzles. The facility provides experimental support for the fluid mechanics research, including experimental verification of aerodynamic computer codes and boundary-layer and airfoil studies that require high Reynolds number simulation. (Tunnel 1)

  20. The emerging High Efficiency Video Coding standard (HEVC)

    NASA Astrophysics Data System (ADS)

    Raja, Gulistan; Khan, Awais

    2013-12-01

    High definition video (HDV) is becoming popular day by day. This paper describes the performance analysis of latest upcoming video standard known as High Efficiency Video Coding (HEVC). HEVC is designed to fulfil all the requirements for future high definition videos. In this paper, three configurations (intra only, low delay and random access) of HEVC are analyzed using various 480p, 720p and 1080p high definition test video sequences. Simulation results show the superior objective and subjective quality of HEVC.

  1. High Efficiency Adsorption Chillers: High Efficiency Adsorption Cooling Using Metal Organic Heat Carriers

    SciTech Connect

    2010-10-01

    BEETIT Project: PNNL is incorporating significant improvements in materials that adsorb liquids or gases to design more efficient adsorption chillers. An adsorption chiller is a type of air conditioner that is powered by heat, solar or waste heat, or combustion of natural gas. Unlike typical chillers, this type has few moving parts and uses almost no electricity to operate. PNNL is designing adsorbent materials at the molecular level with at least 3 times higher refrigerant capacity and up to 20 times faster kinetics than adsorbents used in current chillers. By using the new adsorbent, PNNL is able to create a chiller that is significantly smaller, has twice the energy efficiency, and lower costs for materials and assembly time compared to conventional adsorption chillers.

  2. A high efficiency architecture for cascaded Raman fiber lasers.

    PubMed

    Supradeepa, V R; Nichsolson, Jeffrey W; Headley, Clifford E; Yan, Man F; Palsdottir, Bera; Jakobsen, Dan

    2013-03-25

    We demonstrate a new high efficiency architecture for cascaded Raman fiber lasers based on a single pass cascaded amplifier configuration. Conversion is seeded at all intermediate Stokes wavelengths using a multi-wavelength seed source. A lower power Raman laser based on the conventional cascaded Raman resonator architecture provides a convenient seed source providing all the necessary wavelengths simultaneously. In this work we demonstrate a 1480nm laser pumped by an 1117nm Yb-doped fiber laser with maximum output power of 204W and conversion efficiency of 65% (quantum-limited efficiency is ~75%). We believe both the output power and conversion efficiency (relative to quantum-limited efficiency) are the highest reported for cascaded Raman fiber lasers.

  3. An efficient high power microwave source at 35 GHz using an induction linac free electron accelerator

    SciTech Connect

    Clark, J.C.; Orzechowski, T.J.; Yarema, S.M.

    1986-11-01

    The Electron Laser Facility (ELF) is a free-electron laser (FEL) amplifier operating in the millimeter-wave regime. ELF uses the electron beam produced by the Experimental Test Accelerator (ETA), which is a linear-induction accelerator. We discuss here (1) the experimental results reflecting the high-peak-power output and high-extraction efficiency obtained from an FEL amplifier operated with a tapered wiggler magnetic field and (2) the results of studies of the exponential gain and saturated power obtained from an FEL amplifier with a flat wiggler while we parametrically varied the input power to the amplifier and the beam current into the wiggler.

  4. Facile Synthesis of Porous Dendritic Bimetallic Platinum-Nickel Nanocrystals as Efficient Catalysts for the Oxygen Reduction Reaction.

    PubMed

    Eid, Kamel; Wang, Hongjing; Malgras, Victor; Alothman, Zeid Abdullah; Yamauchi, Yusuke; Wang, Liang

    2016-05-01

    Certain bimetallic nanocrystals (NCs) possess promising catalytic properties for electrochemical energy conversion. Herein, we report a facile method for the one-step synthesis of porous dendritic PtNi NCs in aqueous solution at room temperature that contrasts with the traditional multistep thermal decomposition approach. The dendritic PtNi NCs assembled by interconnected arms are efficient catalysts for the oxygen reduction reaction. This direct and efficient method is favorable for the up-scaled synthesis of active catalysts used in electrochemical applications. PMID:26879517

  5. High efficiency tantalum-based ceramic composite structures

    NASA Technical Reports Server (NTRS)

    Stewart, David A. (Inventor); Leiser, Daniel B. (Inventor); DiFiore, Robert R. (Inventor); Katvala, Victor W. (Inventor)

    2010-01-01

    Tantalum-based ceramics are suitable for use in thermal protection systems. These composite structures have high efficiency surfaces (low catalytic efficiency and high emittance), thereby reducing heat flux to a spacecraft during planetary re-entry. These ceramics contain tantalum disilicide, molybdenum disilicide and borosilicate glass. The components are milled, along with a processing aid, then applied to a surface of a porous substrate, such as a fibrous silica or carbon substrate. Following application, the coating is then sintered on the substrate. The composite structure is substantially impervious to hot gas penetration and capable of surviving high heat fluxes at temperatures approaching 3000.degree. F. and above.

  6. Mid-infrared interband cascade photodetectors with high quantum efficiency

    NASA Astrophysics Data System (ADS)

    Tian, Zhao-Bing; Singh, Anjali; Rigg, Kevin; Krishna, Sanjay

    2016-02-01

    Antimony-based Interband Cascade (IC) photodetectors are emerging as viable candidates for highperformance infrared applications, especially at high operating temperatures. In our previous IC detector designs using InAs/GaSb Type-II superlattices, the quantum efficiency was relatively low as the designs were optimized for high signal to noise ratio. Here we report our recent development of low-noise mid-IR IC photodetectors with high external quantum efficiency. By adopting IC detectors with thicker absorber designs, the quantum efficiency of these mid-IR IC detectors has been increased up to 35%. These IC devices continue to have low-dark current and high temperature operations. Some further analysis on the device characteristics is also presented.

  7. Metal–Dielectric Waveguides for High Efficiency Fluorescence Imaging

    PubMed Central

    Zhu, Liangfu; Zhang, Douguo; Wang, Ruxue; Wang, Pei; Ming, Hai; Badugu, Ramachandram; Du, Luping; Yuan, Xiaocong; Lakowicz, Joseph R.

    2015-01-01

    We demonstrate that Metal–Dielectric Waveguide structures (MDWs) with high efficiency of fluorescence coupling can be suitable as substrates for fluorescence imaging. This hybrid MDWs consists of a continuous metal film and a dielectric top layer. The optical modes sustaining inside this structure can be excited with a high numerical aperture (N.A) objective, and then focused into a virtual optical probe with high intensity, leading to efficient excitation of fluorophores deposited on top of the MDWs. The emitted fluorophores couple with the optical modes thus enabling the directional emission, which is verified by the back focal plane (BFP) imaging. These unique properties of MDWs have been adopted in a scanning laser confocal optical microscopy, and show the merit of high efficiency fluorescence imaging. MDWs can be easily fabricated by vapor deposition and/or spin coating, the silica surface of the MDWs is suitable for biomolecule tethering, and will offer new opportunities for cell biology and biophysics research. PMID:26525494

  8. Development of high-efficiency solar cells on silicon web

    NASA Technical Reports Server (NTRS)

    Meier, D. L.; Greggi, J.; Okeeffe, T. W.; Rai-Choudhury, P.

    1986-01-01

    Work was performed to improve web base material with a goal of obtaining solar cell efficiencies in excess of 18% (AM1). Efforts in this program are directed toward identifying carrier loss mechanisms in web silicon, eliminating or reducing these mechanisms, designing a high efficiency cell structure with the aid of numerical models, and fabricating high efficiency web solar cells. Fabrication techniques must preserve or enhance carrier lifetime in the bulk of the cell and minimize recombination of carriers at the external surfaces. Three completed cells were viewed by cross-sectional transmission electron microscopy (TEM) in order to investigate further the relation between structural defects and electrical performance of web cells. Consistent with past TEM examinations, the cell with the highest efficiency (15.0%) had no dislocations but did have 11 twin planes.

  9. Conversion efficiency of high-Z backlighter materials

    SciTech Connect

    Keiter, Paul A.; Tierney, Heidi; Workman, Jonathan; Comely, Andrew; Morton, John; Taylor, Mark

    2008-10-15

    High-Z backlighter materials are commonly used as x-ray sources for diagnosing laser-driven experiments. In order to properly plan for experiments and analyze the data, it is important to understand both the number and distribution of photons emitted by the x-ray source when it is irradiated by a laser. The conversion efficiency of L-shell and M-shell emitters is not as well understood as K-shell emitters. The conversion efficiency of the former is typically presented in terms of the entire L- or M-shell spectral region. However, for some applications, one may only want to use a subset of this spectral region. Laser conversion efficiency for L-shell and M-shell emitters suitable for high-energy (>3 keV) absorption spectroscopy is presented at multiple laser intensities. The measured conversion efficiency of the materials ranges from 0.2% to 0.6%.

  10. Development of an Improved High Efficiency Thin Silicon Solar Cell

    NASA Technical Reports Server (NTRS)

    Storti, G.; Wrigley, C.

    1979-01-01

    Breakage and front contact failure in high efficiency, textured ultrathin cells was reduced as a consequence of the introduction of process modifications. In a small production run, over one hundred ultrathin cells, having an average AMO efficiency of 13%, were fabricated from 10-25 ohm cm silicon. An in-house aluminum paste for back surface field formation was developed that resulted in cell efficiencies equivalent to those from commercial pastes. The quality of the back surface field was found to be dependent on the orientation of the silicon slice during alloying.

  11. High efficiency cw laser-pumped tunable alexandrite laser

    SciTech Connect

    Lai, S.T.; Shand, M.L.

    1983-10-01

    High efficiency cw alexandrite laser operation has been achieved. With longitudinal pumping by a krypton laser in a nearly concentric cavity, a 51% output power slope efficiency has been measured. Including the transmission at the input coupler mirror, a quantum yield of 85% has been attained above threshold. Tunability from 726 to 802 nm has also been demonstrated. The low loss and good thermal properties make alexandrite ideal for cw laser operation.

  12. Design of dense transmission diffraction gratings for high efficiency.

    PubMed

    Golub, Michael A

    2015-01-01

    We propose a design method for dense surface-relief diffraction gratings with high efficiency in transmission mode. Closed-form analytical relations between diffraction efficiency, polarization, and grating parameters are derived and verified in the resonance domain of diffraction under general three-dimensional angles of incidence traditionally termed conical mounting. A powerful tool for rigorous design of computer-generated holograms and diffractive optical elements with spectroscopic scale periods is now enabled.

  13. High efficiency inorganic/organic hybrid tandem solar cells.

    PubMed

    Seo, Ji Hoon; Kim, Dong-Ho; Kwon, Se-Hun; Song, Myungkwan; Choi, Min-Seung; Ryu, Seung Yoon; Lee, Hyung Woo; Park, Yun Chang; Kwon, Jung-Dae; Nam, Kee-Seok; Jeong, Yongsoo; Kang, Jae-Wook; Kim, Chang Su

    2012-08-28

    Hybrid tandem solar cells comprising an inorganic bottom cell and an organic top cell have been designed and fabricated. The interlayer combination and thickness matching were optimized in order to increase the overall photovoltaic conversion efficiency. A maximum power conversion efficiency of 5.72% was achieved along with a V(oc) of 1.42 V, reaching as high as 92% of the sum of the subcell V(oc) values. PMID:22807214

  14. High Efficiency Solar Power via Separated Photo and Voltaic Pathways

    SciTech Connect

    Michael J. Naughton

    2009-02-17

    This project demonstrates a novel nanostructured solar cell architecture capable of achieving high efficiency levels that is relatively simple and inexpensive to manufacture. The high efficiency will be achieved by the novel structure that separates the path of the photons from the path of the generated charge carriers. In this way, the photon path can be long for maximum light absorption, while the path for carriers can be short for maximum electronic energy harvesting. The combination of maximum light absorption coupled with maximum carrier harvesting is the basis for the expected high efficiency. The project will develop high efficiency solar cell prototypes utilizing this unique nanostructured architecture. The project addresses the fundamental limitation inherent in all current solar cell designs, and which opens a pathway to development for high efficiency solar cells at low cost. Realizing this goal will result in a levelized cost of electricity in the range of 10¢/kWh, which would achieve the long-sought goal of making photovoltaic electricity cost competitive with fossil-fuel generated electricity without any governmental subsidies. This breakthrough would spur the already rapid growth in the photovoltaic industry to an explosive pace, with significant, widespread benefit to the national economy and the nation’s energy security. The initial target of the program is to develop single-junction solar cells using ultrathin amorphous silicon with the performance approaching that of single crystal silicon cells.

  15. The high-efficiency γ-ray spectroscopy setup γ3 at HIγS

    NASA Astrophysics Data System (ADS)

    Löher, B.; Derya, V.; Aumann, T.; Beller, J.; Cooper, N.; Duchêne, M.; Endres, J.; Fiori, E.; Isaak, J.; Kelley, J.; Knörzer, M.; Pietralla, N.; Romig, C.; Savran, D.; Scheck, M.; Scheit, H.; Silva, J.; Tonchev, A.; Tornow, W.; Weller, H.; Werner, V.; Zilges, A.

    2013-09-01

    The existing Nuclear Resonance Fluorescence (NRF) setup at the HIγS facility at the Triangle Universities Nuclear Laboratory at Duke University has been extended in order to perform γ-γ coincidence experiments. The new setup combines large volume LaBr3 : Ce detectors and high resolution HPGe detectors in a very close geometry to offer high efficiency, high energy resolution as well as high count rate capabilities at the same time. The combination of a highly efficient γ-ray spectroscopy setup with the mono-energetic high-intensity photon beam of HIγS provides a worldwide unique experimental facility to investigate the γ-decay pattern of dipole excitations in atomic nuclei. The performance of the new setup has been assessed by studying the nucleus 32S at 8.125 MeV beam energy. The relative γ-decay branching ratio from the 1+ level at 8125.4 keV to the first excited 2+ state was determined to 15.7(3)%.

  16. Multiple Exciton Generation for Highly Efficient Solar Cells

    NASA Astrophysics Data System (ADS)

    Nozik, Arthur

    2007-03-01

    In order to utilize solar power for the production of electricity and fuel on a massive scale, it will be necessary to develop solar photon conversion systems that have an appropriate combination of high efficiency and low capital cost (/m^2). One new potential approach to high solar cell efficiency is to utilize the unique properties of semiconductor quantum dot nanostructures to control the relaxation dynamics of photogenerated carriers to produce either enhanced photocurrent through efficient multiple exciton generation (MEG) or enhanced photopotential through hot electron transport and transfer processes. To achieve these desirable effects it is necessary to understand and control the dynamics of electron relaxation, cooling, multiple exciton generation , transport, and interfacial electron transfer of the photogenerated carriers with fs to ns time resolution. We have been studying these fundamental dynamics in bulk and nanoscale semiconductors (quantum dots, quantum wires, and quantum wells) using femtosecond transient absorption, photoluminescence, and THz spectroscopy. This work will be summarized and recent advances in creating multiple excitons from a single photon will be discussed, including a unique model to explain efficient MEG based on the coherent superposition of multiple excitonic states. Various possible configurations for quantum dot solar cells that could produce ultra-high conversion efficiencies for the production of electricity, as well as for producing solar fuels (for example, hydrogen from water splitting), will be discussed, along with associated thermodynamic calculations that show the increase in the maximum theoretical gain in solar photon conversion efficiency for both electricity and fuel production.

  17. Traffic control for high occupancy vehicle facilities in Virginia. Final report, March 1995-September 1997

    SciTech Connect

    McGhee, C.C.

    1998-04-01

    High occupancy vehicle (HOV) facilities are an important tool in relieving the congestion that continues to build on many urban roadways. By moving more people in fewer vehicles, the existing infrastructure can be used more efficiently. operating HOV lanes is not a simple matter however. HOV lanes can be controversal, and the task of making them comprehensible and easy to use is not insignificant. The study includes a literature review of signing and pavement marking for special use lanes, a survey of several states with active HOV programs, and a review of the HOV facilities in Virginia. The literature suggests that the majority of motorists do understand the meaning of the term HOV as well as the use of the diamond symbol that indicates an HOV lane. Motorist confusion occurs with HOV regulations are not consistent across a region, however. Varying the hours of operation or minimum vehicle occupancy increases the signing requirements and places a greater burden on motorists. HOV signs must be clear and state the relevant restrictions on use. In addition, other efforts should be undertaken to educate motorists about HOV benefits and requirements for use. Enforcement is critical to the success of HOV programs and should be a coordinated effort between the Department of Transportation and the enforcement agencies.

  18. High-speed, efficient metal - semiconductor - metal photodetectors

    SciTech Connect

    Collin, St; Pardo, F; Bardou, N; Pelouard, J.-L.; Averin, S V

    2010-08-03

    Design principles and the fabrication technique of highly efficient, high-speed photodetectors based on MSM nanostructures are developed. To efficiently confine light in the region of the strong field as well as to decrease light losses due to reflection from the diode contacts, use is made of a nanoscale interdigital diffraction grating and a multilayer Bragg grating. Measurements of the reflection coefficients and the quantum efficiency for a multilayer structure are in good agreement with theoretical estimates. A record-high quantum efficiency (QE = 46 %) is obtained for high speed MSM photodetectors. The detector has a high spectral selectivity ({Delta}{lambda}{sub 1/2} = 17 nm) at a wavelength of 800 nm. Taking into account the diode capacitance and the drift time of photogenerated carriers, the performance of the detectors under study is {approx} 500 GHz. The low level of the dark current density in the structures under study (j={sup 1} pA {mu}m{sup -2}) makes it possible to realise on their basis highly sensitive, high-speed selective detectors of optical radiation.

  19. Highly efficient enrichment of phosphopeptides by a magnetic lanthanide metal-organic framework.

    PubMed

    Xie, Yiqin; Deng, Chunhui

    2016-10-01

    Highly efficient enrichment of phosphopeptides from complex biological samples is crucial prior to mass spectrometry analysis due to the low abundance and ion suppression effects. In this study, a facile route was designed for preparation of a magnetic erbium(Er)-based metal-organic framework (denoted as Fe3O4@PDA@Er(btc)), which was synthesized with 1,3,5-benzenetricarboxylic acid(H3btc) as ligand and grafted on the polydopamine (PDA) - coated Fe3O4. The as-prepared material exhibited ultra-high sensitivity (detection limit of 20amol/μL) and selectivity at a low mass ratio of β-Casein/BSA (1:500). Moreover, it was also investigated for enrichment of phosphopeptides from human serum, which provided a promising technique for highly efficient enrichment of low-abundance phosphorylated peptides in the practical application. PMID:27474271

  20. One-pot facile synthesis of reusable tremella-like M1@M2@M1(OH)2 (M1 = Co, Ni, M2 = Pt/Pd, Pt, Pd and Au) three layers core-shell nanostructures as highly efficient catalysts.

    PubMed

    Liu, Yadong; Fang, Zhen; Kuai, Long; Geng, Baoyou

    2014-08-21

    In this work, a general, facile, successive and eco-friendly method for multilayer nanostructures has been established for the first time. We take full advantage of the structural and compositional character of M1@M2 (M1 = Co, Ni, M2 = Pt/Pd, Pt, Pd and Au) core-shell nanostructures to prepare a series of reusable tremella-like M1@M2@M1(OH)2 three layer core-shell or yolk-shell nanocomposites with a magnetic core, a porous noble metal shell, and an ultrathin cobalt or nickel hydroxide shell. We evaluated their catalytic performance using a model reaction based on the reduction of 4-nitrophenol. These novel M1@M2@M1(OH)2 nanomaterials with a unique internal micro environment promoted the efficiency of the catalytic reaction, prolonged the service life of the catalyst and enhanced the overall activity of the catalyst in the catalytic process. The novel three layer core-shell nanocomposites can be extended to other applications such as biomedical detection, energy conversion and storage systems. PMID:25008373

  1. High Efficient Synthesis of Iron-based Superconductors

    NASA Astrophysics Data System (ADS)

    Fang, Ai-Hua; Huang, Fu-Qiang; Xie, Xiao-Ming; Jiang, Mian-Heng

    We have performed systematic investigations aimed at high efficient synthesis of the 1111 family iron-based superconductors. By using meta-stable reactive starting materials of LnAs and FeO, assisted by mechanical alloying and fast heating, high purity samples with Tconset greater than 50K can be made with sintering temperatures between 1433K-1073K, and sintering time from 20 min to 40 h. High purity phase with sintering temperature as low as 973K was demonstrated successfully although Tconset fall below 50K and weak grain boundary suppressed greatly the zero resistance temperature. Ultra fast microwave sintering brings the sintering time further down to 5 min. Samples prepared by the above high efficient methods typically posses submicron grain and very high upper critical field, indicating very high pinning power. Besides offering cost advantages, the developed methods may play important roles in the exploit of novel superconductors.

  2. High efficiency, high temperature separations on silica based monolithic columns.

    PubMed

    Rogeberg, Magnus; Wilson, Steven Ray; Malerod, Helle; Lundanes, Elsa; Tanaka, Nobuo; Greibrokk, Tyge

    2011-10-14

    The effect of temperature on separation using reversed-phase monolithic columns has been investigated using a nano-LC pumping system for gradient separation of tryptic peptides with MS detection. A goal of this study was to find optimal conditions for high-speed separations. The chromatographic performance of the columns was evaluated by peak capacity and peak capacity per time unit. Column lengths ranging from 20 to 100 cm and intermediate gradient times from 10 to 30 min were investigated to assess the potential of these columns in a final step separation, e.g. after fractionation or specific sample preparation. Flow rates from 250 to 2000 nL/min and temperatures from 20 to 120°C were investigated. Temperature had a significant effect on fast separations, and a flow rate of 2000 nL/min and a temperature of 80°C gave the highest peak capacity per time unit. These settings produced 70% more protein identifications in a biological sample compared to a conventional packed column. Alternatively, an equal amount of protein identifications was obtained with a 40% reduction in run time compared to the conventional packed column.

  3. Shock-Ignited High Gain/Yield Targets for the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Perkins, L. J.; Lafortune, K. N.; Bedrosiian, P.; Tabak, M.; Miles, A.; Dixit, S.; Betti, R.; Anderson, K.; Zhou, C.

    2006-10-01

    Shock-ignition, a new concept for ICF ignition [C.Zhou, R.Betti Bull APS, v50, 2005], is being studied as a future option for efficiently achieving high gains in large laser facilities such as NIF. Accordingly, this offers the potential for testing: (1)High yield (up to 200MJ), reactor-relevant targets for inertial fusion energy (2)High fusion yield targets for DOE NNSA stockpile application (3)Targets with appreciable gain at low laser drive energies (gains of 10's at 150kJ) (4)Ignition of simple, non-cryo (room temperature) single shell gas targets at (unity gain). By contrast to conventional hotspot ignition, we separate the assembly and ignition phases by initially imploding a massive cryogenic shell on a low adiabat (alpha 0.7) at low velocity (less than 2e7cm/s) using a direct drive pulse of modest total energy. The assembled fuel is then separately ignited by a strong, spherically convergent shock driven by a high intensity spike at the end of the pulse and timed to reach the center as the main fuel is stagnating and starting to rebound. Like fast ignition, shock ignition can achieve high gains with low drive energy, but has the advantages of requiring only a single laser with less demanding timing and spatial focusing requirements.

  4. Classical Keggin Intercalated into Layered Double Hydroxides: Facile Preparation and Catalytic Efficiency in Knoevenagel Condensation Reactions.

    PubMed

    Jia, Yueqing; Fang, Yanjun; Zhang, Yingkui; Miras, Haralampos N; Song, Yu-Fei

    2015-10-12

    The family of polyoxometalate (POM) intercalated layered double hydroxide (LDH) composite materials has shown great promise for the design of functional materials with numerous applications. It is known that intercalation of the classical Keggin polyoxometalate (POM) of [PW12 O40 ](3-) (PW12 ) into layered double hydroxides (LDHs) is very unlikely to take place by conventional ion exchange methods due to spatial and geometrical restrictions. In this paper, such an intercalated compound of Mg0.73 Al0.22 (OH)2 [PW12 O40 ]0.04 ⋅0.98 H2 O (Mg3 Al-PW12 ) has been successfully obtained by applying a spontaneous flocculation method. The Mg3 Al-PW12 has been fully characterized by using a wide range of methods (XRD, SEM, TEM, XPS, EDX, XPS, FT-IR, NMR, BET). XRD patterns of Mg3 Al-PW12 exhibit no impurity phase usually observed next to the (003) diffraction peak. Subsequent application of the Mg3 Al-PW12 as catalyst in Knoevenagel condensation reactions of various aldehydes and ketones with Z-CH2 -Z' type substrates (ethyl cyanoacetate and malononitrile) at 60 °C in mixed solvents (V2-propanol :Vwater =2:1) demonstrated highly efficient catalytic activity. The synergistic effect between the acidic and basic sites of the Mg3 Al-PW12 composite proved to be crucial for the efficiency of the condensation reactions. Additionally, the Mg3 Al-PW12 -catalyzed Knoevenagel condensation of benzaldehyde with ethyl cyanoacetate demonstrated the highest turnover number (TON) of 47 980 reported so far for this reaction.

  5. A high-efficiency thermoelectric converter for space applications

    SciTech Connect

    Metzger, J.D.; El-Genk, M.S.

    1990-12-31

    This paper presents a concept for using high-temperature superconducting materials in thermoelectric generators (SCTE) to produce electricity at conversion efficiencies approaching 50% of the Carrot efficiency. The SCTE generator is applicable to systems operating in temperature ranges of high-temperature superconducting materials and thus would be a low-grade converter. Operating in cryogenic temperature ranges provides the advantage of inherently increasing the limits of the Carrot efficiency. Potential applications are for systems operating in space where the ambient temperatures are in the cryogenic temperature range. The advantage of using high-temperature superconducting material in a thermoelectric converter is that it would significantly reduce or eliminate the Joule heating losses in a thermoelectric element. This paper investigates the system aspects and the material requirements of the SCTE converter concept, and presents a conceptual design and an application for a space power system.

  6. Low Cost, High Efficiency, High Pressure Hydrogen Storage

    SciTech Connect

    Mark Leavitt

    2010-03-31

    A technical and design evaluation was carried out to meet DOE hydrogen fuel targets for 2010. These targets consisted of a system gravimetric capacity of 2.0 kWh/kg, a system volumetric capacity of 1.5 kWh/L and a system cost of $4/kWh. In compressed hydrogen storage systems, the vast majority of the weight and volume is associated with the hydrogen storage tank. In order to meet gravimetric targets for compressed hydrogen tanks, 10,000 psi carbon resin composites were used to provide the high strength required as well as low weight. For the 10,000 psi tanks, carbon fiber is the largest portion of their cost. Quantum Technologies is a tier one hydrogen system supplier for automotive companies around the world. Over the course of the program Quantum focused on development of technology to allow the compressed hydrogen storage tank to meet DOE goals. At the start of the program in 2004 Quantum was supplying systems with a specific energy of 1.1-1.6 kWh/kg, a volumetric capacity of 1.3 kWh/L and a cost of $73/kWh. Based on the inequities between DOE targets and Quantum’s then current capabilities, focus was placed first on cost reduction and second on weight reduction. Both of these were to be accomplished without reduction of the fuel system’s performance or reliability. Three distinct areas were investigated; optimization of composite structures, development of “smart tanks” that could monitor health of tank thus allowing for lower design safety factor, and the development of “Cool Fuel” technology to allow higher density gas to be stored, thus allowing smaller/lower pressure tanks that would hold the required fuel supply. The second phase of the project deals with three additional distinct tasks focusing on composite structure optimization, liner optimization, and metal.

  7. Enabling High Efficiency Nanoplasmonics with Novel Nanoantenna Architectures

    PubMed Central

    Cohen, Moshik; Shavit, Reuven; Zalevsky, Zeev

    2015-01-01

    Surface plasmon polaritons (SPPs) are propagating excitations that arise from coupling of light with collective electron oscillations. Characterized by high field intensity and nanometric dimensions, SPPs fashion rapid expansion of interest from fundamental and applicative perspectives. However, high metallic losses at optical frequencies still make nanoplasmonics impractical when high absolute efficiency is paramount, with major challenge is efficient plasmon generation in deep nanoscale. Here we introduce the Plantenna, the first reported nanodevice with the potential of addressing these limitations utilizing novel plasmonic architecture. The Plantenna has simple 2D structure, ultracompact dimensions and is fabricated on Silicon chip for future CMOS integration. We design the Plantenna to feed channel (20 nm × 20 nm) nanoplasmonic waveguides, achieving 52% coupling efficiency with Plantenna dimensions of λ3/17,000. We theoretically and experimentally show that the Plantenna enormously outperforms dipole couplers, achieving 28 dB higher efficiency with broad polarization diversity and huge local field enhancement. Our findings confirm the Plantenna as enabling device for high efficiency plasmonic technologies such as quantum nanoplasmonics, molecular strong coupling and plasmon nanolasers. PMID:26620270

  8. Enabling High Efficiency Nanoplasmonics with Novel Nanoantenna Architectures.

    PubMed

    Cohen, Moshik; Shavit, Reuven; Zalevsky, Zeev

    2015-01-01

    Surface plasmon polaritons (SPPs) are propagating excitations that arise from coupling of light with collective electron oscillations. Characterized by high field intensity and nanometric dimensions, SPPs fashion rapid expansion of interest from fundamental and applicative perspectives. However, high metallic losses at optical frequencies still make nanoplasmonics impractical when high absolute efficiency is paramount, with major challenge is efficient plasmon generation in deep nanoscale. Here we introduce the Plantenna, the first reported nanodevice with the potential of addressing these limitations utilizing novel plasmonic architecture. The Plantenna has simple 2D structure, ultracompact dimensions and is fabricated on Silicon chip for future CMOS integration. We design the Plantenna to feed channel (20 nm × 20 nm) nanoplasmonic waveguides, achieving 52% coupling efficiency with Plantenna dimensions of λ(3)/17,000. We theoretically and experimentally show that the Plantenna enormously outperforms dipole couplers, achieving 28 dB higher efficiency with broad polarization diversity and huge local field enhancement. Our findings confirm the Plantenna as enabling device for high efficiency plasmonic technologies such as quantum nanoplasmonics, molecular strong coupling and plasmon nanolasers. PMID:26620270

  9. Efficiency enhancement in high power backward-wave oscillators

    SciTech Connect

    Goebel, D.M.; Feicht, J.R. Adler, E.A. ); Ponti, E.S. ); Eisenhart, R.L. ); Lemke, R.W. )

    1999-06-01

    High power microwave (HPM) sources based on the backward-wave oscillator (BWO) have been investigated for the past two decades primarily because of their potential for very high efficiency (15 to 40%) operation. Several different effects have been proposed to explain this high efficiency compared to conventional BWO's. One of the major contributors to the high efficiency of the plasma-filled Pasotron HPM BWO source is the presence of optimally phased end reflections. The Pasotron uses a long pulse ([ge]100 [micro]s) plasma-cathode electron-gun and plasma-filled slow-wave structure to produce microwave pulses in the range of 1 to 10 MW without the use of externally produced magnetic fields. The efficiency of the Pasotron can be enhanced by up to a factor of two when the device is configured as a standing-wave oscillator in which properly phased reflections from the downstream collector end of the finite length SWS constructively interfere with the fundamental backward-wave modes and improve the coupling of the beam to the circuit. Operation in this configuration increases the efficiency up to 30% but causes the frequency to vary in discrete steps and the output power to change strongly with beam parameters and oscillation frequency.

  10. Highly efficient integration and expression of piggyBac-derived cassettes in the honeybee (Apis mellifera)

    PubMed Central

    Schulte, Christina; Theilenberg, Eva; Müller-Borg, Marion; Gempe, Tanja; Beye, Martin

    2014-01-01

    Honeybees (Apis mellifera), which are important pollinators of plants, display remarkable individual behaviors that collectively contribute to the organization of a complex society. Advances in dissecting the complex processes of honeybee behavior have been limited in the recent past due to a lack of genetic manipulation tools. These tools are difficult to apply in honeybees because the unit of reproduction is the colony, and many interesting phenotypes are developmentally specified at later stages. Here, we report highly efficient integration and expression of piggyBac-derived cassettes in the honeybee. We demonstrate that 27 and 20% of queens stably transmitted two different expression cassettes to their offspring, which is a 6- to 30-fold increase in efficiency compared with those generally reported in other insect species. This high efficiency implies that an average beekeeping facility with a limited number of colonies can apply this tool. We demonstrated that the cassette stably and efficiently expressed marker genes in progeny under either an artificial or an endogenous promoter. This evidence of efficient expression encourages the use of this system to inhibit gene functions through RNAi in specific tissues and developmental stages by using various promoters. We also showed that the transgenic marker could be used to select transgenic offspring to be employed to facilitate the building of transgenic colonies via the haploid males. We present here the first to our knowledge genetic engineering tool that will efficiently allow for the systematic detection and better understanding of processes underlying the biology of honeybees. PMID:24821811

  11. High power, high efficiency millimeter wavelength traveling wave tubes for high rate communications from deep space

    NASA Technical Reports Server (NTRS)

    Dayton, James A., Jr.

    1991-01-01

    The high-power transmitters needed for high data rate communications from deep space will require a new class of compact, high efficiency traveling wave tubes (TWT's). Many of the recent TWT developments in the microwave frequency range are generically applicable to mm wave devices, in particular much of the technology of computer aided design, cathodes, and multistage depressed collectors. However, because TWT dimensions scale approximately with wavelength, mm wave devices will be physically much smaller with inherently more stringent fabrication tolerances and sensitivity to thermal dissipation.

  12. Second Generation Advanced Reburning for High Efficiency NOx Control

    SciTech Connect

    Roy Payne; Lary Swanson; Antonio Marquez; Ary Chang; Vladimir M. Zamansky; Pete M. Maly; Vitali V. Lissianski

    2000-09-30

    This project is designed to develop a family of novel NO{sub x} control technologies, called Second Generation Advanced Reburning (SGAR) which has the potential to achieve 90+% NO{sub x} control in coal-fired boilers at a significantly lower cost than SCR. The twelfth reporting period in Phase II (July 3-October 15, 2000) included design validation AR-Lean tests (Task No.2.6) in the 10 x 10{sup 6} Btu/hr Tower Furnace. The objective of tests was to determine the efficiency of AR-Lean at higher than optimum OFA/N-Agent injection temperatures in large pilot-scale combustion facility. Tests demonstrated that co-injection of urea with overfire air resulted in NO{sub x} reduction. However, observed NO{sub x} reduction was smaller than that under optimum conditions.

  13. Second Generation Advanced Reburning for High Efficiency NOx Control

    SciTech Connect

    Vladimir Zamansky

    2000-06-30

    This project is designed to develop a family of novel NO{sub x} control technologies, called Second Generation Advanced Reburning (SGAR) which has the potential to achieve 90+ NO{sub x} control in coal-fired boilers at a significantly lower cost than SCR. The eleventh reporting period in Phase II (April 1-June 30, 2000) included design validation AR-Lean tests (Task 2.6) in the 10 x 10{sup 6} Btu/hr Tower Furnace. The objective of tests was to determine the efficiency of AR-Lean at higher than optimum OFA/N-Agent injection temperatures in large pilot-scale combustion facility. Tests demonstrated that co-injection of urea with overfire air resulted in NO{sub x} reduction. However, observed NO{sub x} reduction was smaller than that under optimum conditions.

  14. Second Generation Advanced Reburning for High Efficiency NOx Control

    SciTech Connect

    Vladimir M. Zamansky; Peter M. Maly; Vitali V. Lissianski

    1999-06-30

    This project is designed to develop a family of novel NO{sub x} control technologies, called Second Generation Advanced Reburning which has the potential to achieve 90+ NO{sub x} control in coal fired boilers at a significantly lower cost than Selective Catalytic Reduction. The seventh reporting period in Phase II (April 1-June 30, 1999) included experimental activities and combined chemistry-mixing modeling on advanced gas reburning. The goal of combustion tests was to determine the efficiency of advanced reburning using coal as the reburning fuel. Tests were conducted in Boiler Simulator Facility (BSF). Several coals were tested. The modeling effort was focused on the description of N-agent injection along with overfire air. Modeling identified process parameters that can be used to optimize the AR-Lean process.

  15. Investigation of beat-waves generation with high efficiency

    SciTech Connect

    Song, W.; Shi, Y. C.; Deng, Y. Q.; Zhu, X. X.; Zhang, Z. Q.; Hu, X. G.

    2013-10-21

    A method for generating high power beating radio-frequency wave with high conversion efficiency is proposed. Based on Cherenkov radiation, two longitudinal resonant modes are excited simultaneously and interacted with intense electron beam synchronously. An experiment was carried out and beat-waves with an average power of about 2.3 GW, frequencies of 9.29 GHz and 10.31 GHz, and efficiency of about 40% were obtained. Through controlling the electron energy, the amplitude proportions of the two resonant modes are altered, and different beat-wave patterns are formed.

  16. High-efficiency transmission gratings fabricated in bulk fused silica

    SciTech Connect

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

    1996-03-01

    The authors present the design and performance of high-efficiency transmission gratings fabricated in bulk fused silica for use in ultraviolet high-power laser systems. The gratings exhibit a diffraction efficiency exceeding 95% in the m = {minus}1 order and damage threshold greater than 13 J/cm{sup 2} for 1 nsec pulses at 351 nm. Model calculations and experimental measurements are in good agreement. They describe the design and fabrication of these gratings based on the transfer ion etching of photoresist patterns produced by interference lithography.

  17. Investigation of beat-waves generation with high efficiency

    NASA Astrophysics Data System (ADS)

    Song, W.; Shi, Y. C.; Deng, Y. Q.; Zhu, X. X.; Zhang, Z. Q.; Hu, X. G.

    2013-10-01

    A method for generating high power beating radio-frequency wave with high conversion efficiency is proposed. Based on Cherenkov radiation, two longitudinal resonant modes are excited simultaneously and interacted with intense electron beam synchronously. An experiment was carried out and beat-waves with an average power of about 2.3 GW, frequencies of 9.29 GHz and 10.31 GHz, and efficiency of about 40% were obtained. Through controlling the electron energy, the amplitude proportions of the two resonant modes are altered, and different beat-wave patterns are formed.

  18. High efficiency III-nitride light-emitting diodes

    DOEpatents

    Crawford, Mary; Koleske, Daniel; Cho, Jaehee; Zhu, Di; Noemaun, Ahmed; Schubert, Martin F; Schubert, E. Fred

    2013-05-28

    Tailored doping of barrier layers enables balancing of the radiative recombination among the multiple-quantum-wells in III-Nitride light-emitting diodes. This tailored doping enables more symmetric carrier transport and uniform carrier distribution which help to reduce electron leakage and thus reduce the efficiency droop in high-power III-Nitride LEDs. Mitigation of the efficiency droop in III-Nitride LEDs may enable the pervasive market penetration of solid-state-lighting technologies in high-power lighting and illumination.

  19. High efficiency silicon solar cell based on asymmetric nanowire

    PubMed Central

    Ko, Myung-Dong; Rim, Taiuk; Kim, Kihyun; Meyyappan, M.; Baek, Chang-Ki

    2015-01-01

    Improving the efficiency of solar cells through novel materials and devices is critical to realize the full potential of solar energy to meet the growing worldwide energy demands. We present here a highly efficient radial p-n junction silicon solar cell using an asymmetric nanowire structure with a shorter bottom core diameter than at the top. A maximum short circuit current density of 27.5 mA/cm2 and an efficiency of 7.53% were realized without anti-reflection coating. Changing the silicon nanowire (SiNW) structure from conventional symmetric to asymmetric nature improves the efficiency due to increased short circuit current density. From numerical simulation and measurement of the optical characteristics, the total reflection on the sidewalls is seen to increase the light trapping path and charge carrier generation in the radial junction of the asymmetric SiNW, yielding high external quantum efficiency and short circuit current density. The proposed asymmetric structure has great potential to effectively improve the efficiency of the SiNW solar cells. PMID:26152914

  20. High efficiency all-polymer tandem solar cells

    NASA Astrophysics Data System (ADS)

    Yuan, Jianyu; Gu, Jinan; Shi, Guozheng; Sun, Jianxia; Wang, Hai-Qiao; Ma, Wanli

    2016-05-01

    In this work, we have reported for the first time an efficient all-polymer tandem cell using identical sub-cells based on P2F-DO:N2200. A high power conversion efficiency (PCE) of 6.70% was achieved, which is among the highest efficiencies for all polymer solar cells and 43% larger than the PCE of single junction cell. The largely improved device performance can be mainly attributed to the enhanced absorption of tandem cell. Meanwhile, the carrier collection in device remains efficient by optimizing the recombination layer and sub-cell film thickness. Thus tandem structure can become an easy approach to effectively boost the performance of current all polymer solar cells.

  1. High efficiency all-polymer tandem solar cells

    PubMed Central

    Yuan, Jianyu; Gu, Jinan; Shi, Guozheng; Sun, Jianxia; Wang, Hai-Qiao; Ma, Wanli

    2016-01-01

    In this work, we have reported for the first time an efficient all-polymer tandem cell using identical sub-cells based on P2F-DO:N2200. A high power conversion efficiency (PCE) of 6.70% was achieved, which is among the highest efficiencies for all polymer solar cells and 43% larger than the PCE of single junction cell. The largely improved device performance can be mainly attributed to the enhanced absorption of tandem cell. Meanwhile, the carrier collection in device remains efficient by optimizing the recombination layer and sub-cell film thickness. Thus tandem structure can become an easy approach to effectively boost the performance of current all polymer solar cells. PMID:27226354

  2. High efficiency all-polymer tandem solar cells.

    PubMed

    Yuan, Jianyu; Gu, Jinan; Shi, Guozheng; Sun, Jianxia; Wang, Hai-Qiao; Ma, Wanli

    2016-01-01

    In this work, we have reported for the first time an efficient all-polymer tandem cell using identical sub-cells based on P2F-DO:N2200. A high power conversion efficiency (PCE) of 6.70% was achieved, which is among the highest efficiencies for all polymer solar cells and 43% larger than the PCE of single junction cell. The largely improved device performance can be mainly attributed to the enhanced absorption of tandem cell. Meanwhile, the carrier collection in device remains efficient by optimizing the recombination layer and sub-cell film thickness. Thus tandem structure can become an easy approach to effectively boost the performance of current all polymer solar cells. PMID:27226354

  3. High extraction efficiency ultraviolet light-emitting diode

    DOEpatents

    Wierer, Jonathan; Montano, Ines; Allerman, Andrew A.

    2015-11-24

    Ultraviolet light-emitting diodes with tailored AlGaN quantum wells can achieve high extraction efficiency. For efficient bottom light extraction, parallel polarized light is preferred, because it propagates predominately perpendicular to the QW plane and into the typical and more efficient light escape cones. This is favored over perpendicular polarized light that propagates along the QW plane which requires multiple, lossy bounces before extraction. The thickness and carrier density of AlGaN QW layers have a strong influence on the valence subband structure, and the resulting optical polarization and light extraction of ultraviolet light-emitting diodes. At Al>0.3, thinner QW layers (<2.5 nm are preferred) result in light preferentially polarized parallel to the QW plane. Also, active regions consisting of six or more QWs, to reduce carrier density, and with thin barriers, to efficiently inject carriers in all the QWs, are preferred.

  4. UTILIZATION OF COMPUTER FACILITIES IN THE MATHEMATICS AND BUSINESS CURRICULUM IN A LARGE SUBURBAN HIGH SCHOOL.

    ERIC Educational Resources Information Center

    RENO, MARTIN; AND OTHERS

    A STUDY WAS UNDERTAKEN TO EXPLORE IN A QUALITATIVE WAY THE POSSIBLE UTILIZATION OF COMPUTER AND DATA PROCESSING METHODS IN HIGH SCHOOL EDUCATION. OBJECTIVES WERE--(1) TO ESTABLISH A WORKING RELATIONSHIP WITH A COMPUTER FACILITY SO THAT ABLE STUDENTS AND THEIR TEACHERS WOULD HAVE ACCESS TO THE FACILITIES, (2) TO DEVELOP A UNIT FOR THE UTILIZATION…

  5. Realization of highly efficient hexagonal boron nitride neutron detectors

    NASA Astrophysics Data System (ADS)

    Maity, A.; Doan, T. C.; Li, J.; Lin, J. Y.; Jiang, H. X.

    2016-08-01

    We report the achievement of highly efficient 10B enriched hexagonal boron nitride (h-10BN) direct conversion neutron detectors. These detectors were realized from freestanding 4-in. diameter h-10BN wafers 43 μm in thickness obtained from epitaxy growth and subsequent mechanical separation from sapphire substrates. Both sides of the film were subjected to ohmic contact deposition to form a simple vertical "photoconductor-type" detector. Transport measurements revealed excellent vertical transport properties including high electrical resistivity (>1013 Ω cm) and mobility-lifetime (μτ) products. A much larger μτ product for holes compared to that of electrons along the c-axis of h-BN was observed, implying that holes (electrons) behave like majority (minority) carriers in undoped h-BN. Exposure to thermal neutrons from a californium-252 (252Cf) source moderated by a high density polyethylene moderator reveals that 43 μm h-10BN detectors possess 51.4% detection efficiency at a bias voltage of 400 V, which is the highest reported efficiency for any semiconductor-based neutron detector. The results point to the possibility of obtaining highly efficient, compact solid-state neutron detectors with high gamma rejection and low manufacturing and maintenance costs.

  6. A test stand for the evaluation of high efficiency mist eliminators

    NASA Astrophysics Data System (ADS)

    Giffin, Paxton K.; Parsons, Michael S.; Waggoner, Charles A.

    2012-10-01

    High efficiency mist eliminators (HEME) are airstream filtering elements primarily used to remove liquid and solid aerosols. HEME elements are designed to reduce aerosol load on downstream high efficiency particulate air filters and to have a liquid particle removal efficiency of 99.5% for aerosols as small as 1 μm in size. The test stand described herein is designed to evaluate the loading capacity and filtering efficiency of a single HEME element. The loading capacity was determined with or without use of a water spray cleaning system to wash the interior surface of the element. The HEME element is challenged with a liquid waste surrogate using Laskin nozzles and large dispersion nozzles. The waste surrogate used was a highly caustic solution with both suspended and dissolved solids representative of actual exposures at mixed, hazardous, and radiological, waste treatment facilities. The filtering efficiency performance was determined by challenging the element with a dried waste surrogate aerosol and di-octyl phthalate intermittently during the loading process. Capabilities of the test stand and representative results obtained during testing are presented.

  7. Scaling Studies for High Temperature Test Facility and Modular High Temperature Gas-Cooled Reactor

    SciTech Connect

    Richard R. Schult; Paul D. Bayless; Richard W. Johnson; James R. Wolf; Brian Woods

    2012-02-01

    The Oregon State University (OSU) High Temperature Test Facility (HTTF) is an integral experimental facility that will be constructed on the OSU campus in Corvallis, Oregon. The HTTF project was initiated, by the U.S. Nuclear Regulatory Commission (NRC), on September 5, 2008 as Task 4 of the 5-year High Temperature Gas Reactor Cooperative Agreement via NRC Contract 04-08-138. Until August, 2010, when a DOE contract was initiated to fund additional capabilities for the HTTF project, all of the funding support for the HTTF was provided by the NRC via their cooperative agreement. The U.S. Department of Energy (DOE) began their involvement with the HTTF project in late 2009 via the Next Generation Nuclear Plant (NGNP) project. Because the NRC's interests in HTTF experiments were only centered on the depressurized conduction cooldown (DCC) scenario, NGNP involvement focused on expanding the experimental envelope of the HTTF to include steady-state operations and also the pressurized conduction cooldown (PCC).

  8. ENERGY EFFICIENCY UPGRADES FOR SANITATION FACILITIES IN SELAWIK, AK FINAL REPORT

    SciTech Connect

    POLLIS, REBECCA

    2014-10-17

    The Native Village of Selawik is a federally recognized Alaskan tribe, located at the mouth of the Selawik River, about 90 miles east of Kotzebue in northwest Alaska. Due to the community’s rural location and cold climate, it is common for electric rates to be four times higher than the cost urban residents pay. These high energy costs were the driving factor for Selawik pursuing funding from the Department of Energy in order to achieve significant energy cost savings. The main objective of the project was to improve the overall energy efficiency of the water treatment/distribution and sewer collection systems in Selawik by implementing the retrofit measures identified in a previously conducted utility energy audit. One purpose for the proposed improvements was to enable the community to realize significant savings associated with the cost of energy. Another purpose of the upgrades was to repair the vacuum sewer system on the west side of Selawik to prevent future freeze-up problems during winter months.

  9. Innovative-Simplified Nuclear Power Plant Efficiency Evaluation with High-Efficiency Steam Injector System

    SciTech Connect

    Shoji, Goto; Shuichi, Ohmori; Michitsugu, Mori

    2006-07-01

    It is possible to establish simplified system with reduced space and total equipment weight using high-efficiency Steam Injectors (SI) instead of low-pressure feedwater heaters in Nuclear Power Plant (NPP). The SI works as a heat exchanger through direct contact between feedwater from condensers and extracted steam from turbines. It can get higher pressure than supplied steam pressure. The maintenance and reliability are still higher than the feedwater ones because SI has no movable parts. This paper describes the analysis of the heat balance, plant efficiency and the operation of this Innovative-Simplified NPP with high-efficiency SI. The plant efficiency and operation are compared with the electric power of 1100 MWe-class BWR system and the Innovative-Simplified BWR system with SI. The SI model is adapted into the heat balance simulator with a simplified model. The results show that plant efficiencies of the Innovated-Simplified BWR system are almost equal to original BWR ones. The present research is one of the projects that are carried out by Tokyo Electric Power Company, Toshiba Corporation, and six Universities in Japan, funded from the Institute of Applied Energy (IAE) of Japan as the national public research-funded program. (authors)

  10. Guidance for the Implementation and Follow-up of Identified Energy and Water Efficiency Measures in Covered Facilities

    SciTech Connect

    2012-09-01

    This document provides specific guidance to agencies on the implementation and follow-up of energy and water efficiency measures identified and undertaken per Section 432 of the Energy Independence and Security Act of 2007 (EISA) (42 U.S.C. 8253(f)(4) and (5)) This guidance also provides context for how these activities fit into the comprehensive approach to facility energy and water management outlined by the statute and incorporates by reference previous DOE guidance released for Section 432 of EISA and other related documents. 42 U.S.C. 8253(f)(7)(A) specifies that facility energy managers shall certify compliance for each covered facility with the 42 U.S.C. 8253(f)(2)-(5) requirements via a web-based tracking system and make it publicly available. This document also describes the role of the tracking system that has been developed for the collection and reporting of data needed for the demonstration of compliance and progress toward meeting all energy and water efficiency requirements outlined in the statute.

  11. Potential high efficiency solar cells: Applications from space photovoltaic research

    NASA Technical Reports Server (NTRS)

    Flood, D. J.

    1986-01-01

    NASA involvement in photovoltaic energy conversion research development and applications spans over two decades of continuous progress. Solar cell research and development programs conducted by the Lewis Research Center's Photovoltaic Branch have produced a sound technology base not only for the space program, but for terrestrial applications as well. The fundamental goals which have guided the NASA photovoltaic program are to improve the efficiency and lifetime, and to reduce the mass and cost of photovoltaic energy conversion devices and arrays for use in space. The major efforts in the current Lewis program are on high efficiency, single crystal GaAs planar and concentrator cells, radiation hard InP cells, and superlattice solar cells. A brief historical perspective of accomplishments in high efficiency space solar cells will be given, and current work in all of the above categories will be described. The applicability of space cell research and technology to terrestrial photovoltaics will be discussed.

  12. Overview of SERI's high efficiency solar cell research

    NASA Technical Reports Server (NTRS)

    Benner, J. P.; Cole, L. A.; Leboeuf, C. M.

    1985-01-01

    The bulk of the research efforts supported by the Solar Energy Research Institute (SERI) High Efficiency Concepts area has been directed towards establishing the feasibility of achieving very high efficiencies, 30% for concentrator and more than 20% for thin film flat plate, in solar cell designs which could possibly be produced competitively. The research has accomplished a great deal during the past two years. Even though the desired performance levels have not yet been demonstrated, based on the recent progress, a greater portion of the terrestrial photovoltaics community believes that these efficiencies are attainable. The program will now allocate a larger portion of resources to low cost, large area deposition technology. The program is currently shifting greater emphasis on to the study of crystal growth in order to provide the understanding and tools needed to design a large area process.

  13. Low Threshold and High Efficiency Nd:S-VAP Laser

    NASA Astrophysics Data System (ADS)

    Zhao, Shengzhi; Wang, Qingpu; Zhang, Xingyu; Wang, Xiaojie; Wang, Xiangtai; Sun, Lianke; Zhang, Shaojun

    1995-06-01

    The absorption spectrum of a new sort of crystal Nd:S-VAP was measured, which showed that Nd:S-VAP can be appropriately pumped at 583.0 and 809.0 nm. By using tunable dye-laser (570.0-600.0 nm) as pumping light, the performance of low threshold and high efficiency Nd:S-VAP laser has been realized. The characteristics of the output laser, such as 1.5 nm linewidth, 5 ns pulse width, almost total polarity, up to 50% conversion efficiency, down to 2 mJ threshold energy and so on, were presented. Meanwhile, the prospect of Nd:S-VAP crystal for low threshold, high efficiency miniature laser was discussed.

  14. Highly efficient light management for perovskite solar cells

    PubMed Central

    Wang, Dong-Lin; Cui, Hui-Juan; Hou, Guo-Jiao; Zhu, Zhen-Gang; Yan, Qing-Bo; Su, Gang

    2016-01-01

    Organic-inorganic halide perovskite solar cells have enormous potential to impact the existing photovoltaic industry. As realizing a higher conversion efficiency of the solar cell is still the most crucial task, a great number of schemes were proposed to minimize the carrier loss by optimizing the electrical properties of the perovskite solar cells. Here, we focus on another significant aspect that is to minimize the light loss by optimizing the light management to gain a high efficiency for perovskite solar cells. In our scheme, the slotted and inverted prism structured SiO2 layers are adopted to trap more light into the solar cells, and a better transparent conducting oxide layer is employed to reduce the parasitic absorption. For such an implementation, the efficiency and the serviceable angle of the perovskite solar cell can be promoted impressively. This proposal would shed new light on developing the high-performance perovskite solar cells. PMID:26733112

  15. High efficiency micro solar cells integrated with lens array

    NASA Astrophysics Data System (ADS)

    Fidaner, Onur; Suarez, Ferran A.; Wiemer, Michael; Sabnis, Vijit A.; Asano, Tetsuya; Itou, Akihiro; Inoue, Daijiro; Hayashi, Nobuhiko; Arase, Hidekazu; Matsushita, Akio; Nakagawa, Tohru

    2014-03-01

    We demonstrate high efficiency triple junction solar cells with submillimeter dimensions in an all-back-contact architecture. 550 × 550 μm2 cells flash at 41.3% efficiency under the air mass 1.5 direct normal spectrum at 50 W/cm2 at 25 °C. Compared to standard size production cells, the micro cells have reduced performance at 1-sun due to perimeter recombination, but the performance gap closes at higher concentrations. Micro cells integrated with lens arrays were tested on-sun with an efficiency of 34.7%. All-back-contact architecture and submillimeter dimensions are advantageous for module integration and heat dissipation, allowing for high-performance, compact, lightweight, and cost-effective concentrated photovoltaic modules.

  16. Highly efficient light management for perovskite solar cells.

    PubMed

    Wang, Dong-Lin; Cui, Hui-Juan; Hou, Guo-Jiao; Zhu, Zhen-Gang; Yan, Qing-Bo; Su, Gang

    2016-01-06

    Organic-inorganic halide perovskite solar cells have enormous potential to impact the existing photovoltaic industry. As realizing a higher conversion efficiency of the solar cell is still the most crucial task, a great number of schemes were proposed to minimize the carrier loss by optimizing the electrical properties of the perovskite solar cells. Here, we focus on another significant aspect that is to minimize the light loss by optimizing the light management to gain a high efficiency for perovskite solar cells. In our scheme, the slotted and inverted prism structured SiO2 layers are adopted to trap more light into the solar cells, and a better transparent conducting oxide layer is employed to reduce the parasitic absorption. For such an implementation, the efficiency and the serviceable angle of the perovskite solar cell can be promoted impressively. This proposal would shed new light on developing the high-performance perovskite solar cells.

  17. Consideration for high accuracy radiation efficiency measurements for the Solar Power Satellite (SPS) subarrays

    NASA Technical Reports Server (NTRS)

    Kozakoff, D. J.; Schuchardt, J. M.; Ryan, C. E.

    1980-01-01

    The transmit beam and radiation efficiency for 10 metersquare subarray panels were quantified. Measurement performance potential of far field elevated and ground reflection ranges and near field technique were evaluated. The state-of-the-art of critical components and/or unique facilities required was identified. Relative cost, complexity and performance tradeoffs were performed for techniques capable of achieving accuracy objectives. It is considered that because of the large electrical size of the SPS subarray panels and the requirement for high accuracy measurements, specialized measurement facilities are required. Most critical measurement error sources have been identified for both conventional far field and near field techniques. Although the adopted error budget requires advances in state-of-the-art of microwave instrumentation, the requirements appear feasible based on extrapolation from today's technology. Additional performance and cost tradeoffs need to be completed before the choice of the preferred measurement technique is finalized.

  18. Energy Efficient Florida Educational Facilities. Improvements to a Portable Classroom in a Volusia County School.

    ERIC Educational Resources Information Center

    Callahan, Michael P.; Parker, Danny S.

    The Florida Department of Education is monitoring the energy use of two adjacent portable classrooms to compare their energy efficiency in a hot and humid climate and determine if they can be made more energy efficient either by retrofit or when the portables were constructed. This report provides the background of this research and describes the…

  19. Complex in vivo Ligation Using Homologous Recombination and High-efficiency Plasmid Rescue from Saccharomyces cerevisiae

    PubMed Central

    Finnigan, Gregory C.; Thorner, Jeremy

    2015-01-01

    The protocols presented here allow for the facile generation of a wide variety of complex multipart DNA constructs (tagged gene products, gene fusions, chimeric proteins, and other variants) using homologous recombination and in vivo ligation in budding yeast (Saccharomyces cerevisiae). This method is straightforward, efficient and cost-effective, and can be used both for vector creation and for subsequent one-step, high frequency integration into a chromosomal locus in yeast. The procedure utilizes PCR with extended oligonucleotide “tails” of homology between multiple fragments to allow for reassembly in yeast in a single transformation followed by a method for highly efficient plasmid extraction from yeast (for transformation into bacteria). The latter is an improvement on existing methods of yeast plasmid extraction, which, historically, has been a limiting step in recovery of desired constructs. We describe the utility and convenience of our techniques, and provide several examples. PMID:26523287

  20. Basic studies of 3-5 high efficiency cell components

    SciTech Connect

    Lundstrom, M.S.; Melloch, M.R.; Pierret, R.F.; Carpenter, M.S.; Chuang, H.L.; Dodd, P.E.; Keshavarzi, A.; Klausmeier-Brown, M.E.; Lush, G.B.; Stellwag, T.B. )

    1993-01-01

    This project's objective is to improve our understanding of the generation, recombination, and transport of carriers within III-V homo- and heterostructures. The research itself consists of fabricating and characterizing solar cell building blocks'' such as junctions and heterojunctions as well as basic measurements of material parameters. A significant effort is also being directed at characterizing loss mechanisms in high-quality, III-V solar cells fabricated in industrial research laboratories throughout the United States. The project's goal is to use our understanding of the device physics of high-efficiency cell components to maximize cell efficiency. A related goal is the demonstration of new cell structures fabricated by molecular beam epitaxy (MBE). The development of measurement techniques and characterization methodologies is also a project objective. This report describes our progress during the fifth and final year of the project. During the past five years, we've teamed a great deal about heavy doping effects in p[sup +] and n[sup +] GaAs and have explored their implications for solar cells. We have developed an understanding of the dominant recombination losses in present-day, high-efficiency cells. We've learned to appreciated the importance of recombination at the perimeter of the cell and have developed techniques for chemically passivating such edges. Finally, we've demonstrated that films grown by molecular beam epitaxy are suitable for high-efficiency cell research.

  1. Development of a high efficiency thin silicon solar cell

    NASA Technical Reports Server (NTRS)

    Lindmayer, J.

    1975-01-01

    Progress is reported in an attempt to realize higher specific power output and radiation resistance from thin solar cells for space applications. The efforts applied to establishing the technological base for fabricating high efficiency thin solar cells are described. Progress is characterized by continuous improvements in all parameters of the space cell.

  2. Development of a high efficiency thin silicon solar cell

    NASA Technical Reports Server (NTRS)

    Lindmayer, J.

    1975-01-01

    Specific power output and radiation resistance characteristics developed for thin film silicon solar cells are reported. The technological base for fabricating these high efficiency cells and limitations of cell photovoltage are included. In addition, optical and electronic measurement instrumentation and mathematical analyses aids are included. Antireflection coatings for these cells are discussed.

  3. Development of High Efficiency (14%) Solar Cell Array Module

    NASA Technical Reports Server (NTRS)

    Iles, P. A.; Khemthong, S.; Olah, S.; Sampson, W. J.; Ling, K. S.

    1979-01-01

    High efficiency solar cells required for the low cost modules was developed. The production tooling for the manufacture of the cells and modules was designed. The tooling consisted of: (1) back contact soldering machine; (2) vacuum pickup; (3) antireflective coating tooling; and (4) test fixture.

  4. Basic studies of 3-5 high efficiency cell components

    NASA Astrophysics Data System (ADS)

    Lundstrom, M. S.; Melloch, M. R.; Pierret, R. F.; Carpenter, M. S.; Chuang, H. L.; Dodd, P. E.; Keshavarzi, A.; Klausmeier-Brown, M. E.; Lush, G. B.; Stellwag, T. B.

    1993-01-01

    This project's objective is to improve our understanding of the generation, recombination, and transport of carriers within III-V homo- and heterostructures. The research itself consists of fabricating and characterizing solar cell 'building blocks' such as junctions and heterojunctions as well as basic measurements of material parameters. A significant effort is also being directed at characterizing loss mechanisms in high-quality, III-V solar cells fabricated in industrial research laboratories throughout the United States. The project's goal is to use our understanding of the device physics of high-efficiency cell components to maximize cell efficiency. A related goal is the demonstration of new cell structures fabricated by molecular beam epitaxy (MBE). The development of measurement techniques and characterization methodologies is also a project objective. This report describes our progress during the fifth and final year of the project. During the past five years, we've teamed a great deal about heavy doping effects in p(sup +) and n(sup +) GaAs and have explored their implications for solar cells. We have developed an understanding of the dominant recombination losses in present-day, high-efficiency cells. We've learned to appreciated the importance of recombination at the perimeter of the cell and have developed techniques for chemically passivating such edges. Finally, we've demonstrated that films grown by molecular beam epitaxy are suitable for high-efficiency cell research.

  5. High-efficiency K-band tracking antenna feed

    NASA Technical Reports Server (NTRS)

    Beavin, R. L.; Simanyi, A. I.

    1975-01-01

    Antenna feed features high aperture efficiency of multimode near-field horn and develops tracking signals without conventional monopulse bridge. Feed assembly is relatively simple and very compact. However, feed is sensitive to cross-polarized energy which couples into orthogonal error channel.

  6. 40 CFR 761.71 - High efficiency boilers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROHIBITIONS Storage and Disposal § 761.71 High efficiency boilers. (a) To burn mineral oil dielectric fluid... percent when PCBs are being burned. (iv) The mineral oil dielectric fluid does not comprise more than 10 percent (on a volume basis) of the total fuel feed rate. (v) The mineral oil dielectric fluid is not...

  7. 40 CFR 761.71 - High efficiency boilers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROHIBITIONS Storage and Disposal § 761.71 High efficiency boilers. (a) To burn mineral oil dielectric fluid... percent when PCBs are being burned. (iv) The mineral oil dielectric fluid does not comprise more than 10 percent (on a volume basis) of the total fuel feed rate. (v) The mineral oil dielectric fluid is not...

  8. 40 CFR 761.71 - High efficiency boilers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROHIBITIONS Storage and Disposal § 761.71 High efficiency boilers. (a) To burn mineral oil dielectric fluid... percent when PCBs are being burned. (iv) The mineral oil dielectric fluid does not comprise more than 10 percent (on a volume basis) of the total fuel feed rate. (v) The mineral oil dielectric fluid is not...

  9. 40 CFR 761.71 - High efficiency boilers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PROHIBITIONS Storage and Disposal § 761.71 High efficiency boilers. (a) To burn mineral oil dielectric fluid... percent when PCBs are being burned. (iv) The mineral oil dielectric fluid does not comprise more than 10 percent (on a volume basis) of the total fuel feed rate. (v) The mineral oil dielectric fluid is not...

  10. 40 CFR 761.71 - High efficiency boilers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PROHIBITIONS Storage and Disposal § 761.71 High efficiency boilers. (a) To burn mineral oil dielectric fluid... percent when PCBs are being burned. (iv) The mineral oil dielectric fluid does not comprise more than 10 percent (on a volume basis) of the total fuel feed rate. (v) The mineral oil dielectric fluid is not...

  11. Super Boiler: First Generation, Ultra-High Efficiency Firetube Boiler

    SciTech Connect

    2006-06-01

    This factsheet describes a research project whose goal is to develop and demonstrate a first-generation ultra-high-efficiency, ultra-low emissions, compact gas-fired package boiler (Super Boiler), and formulate a long-range RD&D plan for advanced boiler technology out to the year 2020.

  12. High efficiency solar cells for laser power beaming applications

    NASA Technical Reports Server (NTRS)

    Jain, Raj K.; Landis, G. A.

    1995-01-01

    Understanding solar cell response to pulsed laser outputs is important for the evaluation of power beaming applications. The time response of high efficiency GaAs and silicon solar cells to a 25 nS monochromatic pulse input is described. The PC-1D computer code is used to analyze the cell current during and after the pulse for various conditions.

  13. High-quantum efficiency, long-lived luminescing refractory oxides

    DOEpatents

    Chen, Yok; Gonzalez, Roberto; Summers, Geoffrey P.

    1984-01-01

    A crystal having a high-quantum efficiency and a long period of luminescence is formed of an oxide selected from the group consisting of magnesium oxide and calcium oxide and possessing a concentration ratio of H.sup.- ions to F centers in the range of about 0.05 to about 10.

  14. High-quantum efficiency, long-lived luminescing refractory oxides

    DOEpatents

    Chen, Y.; Gonzalez, R.; Summers, G.P.

    A crystal having a high-quantum efficiency and a long period of luminescence is formed of MgO or CaO and possessing a concentration ratio of H/sup -/ ions to F centers in the range of about 0.05 to about 10.

  15. Evaluation of high efficiency gene knockout strategies for Trypanosoma cruzi

    PubMed Central

    2009-01-01

    Background Trypanosoma cruzi, a kinetoplastid protozoan parasite that causes Chagas disease, infects approximately 15 million people in Central and South America. In contrast to the substantial in silico studies of the T. cruzi genome, transcriptome, and proteome, only a few genes have been experimentally characterized and validated, mainly due to the lack of facile methods for gene manipulation needed for reverse genetic studies. Current strategies for gene disruption in T. cruzi are tedious and time consuming. In this study we have compared the conventional multi-step cloning technique with two knockout strategies that have been proven to work in other organisms, one-step-PCR- and Multisite Gateway-based systems. Results While the one-step-PCR strategy was found to be the fastest method for production of knockout constructs, it does not efficiently target genes of interest using gene-specific sequences of less than 80 nucleotides. Alternatively, the Multisite Gateway based approach is less time-consuming than conventional methods and is able to efficiently and reproducibly delete target genes. Conclusion Using the Multisite Gateway strategy, we have rapidly produced constructs that successfully produce specific gene deletions in epimastigotes of T. cruzi. This methodology should greatly facilitate reverse genetic studies in T. cruzi. PMID:19432966

  16. High-efficiency heteroepitaxial solar cells for space power applications

    NASA Technical Reports Server (NTRS)

    Vernon, S. M.; Tobin, S. P.; Keavney, C. J.; Wojtczuk, S. J.

    1989-01-01

    The experimental results for several technical approaches aimed at achieving highly efficient solar cells for space-power applications are reported. Efficiencies of up to 24.5 percent (170X, AM0) and 21.7 percent (1X, AM0) have been achieved with homoepitaxial GaAs p/n cells. This one-sun AM0 efficiency value is believed to be the highest reported to date. Tandem solar cells utilizing GaAs-on-Ge structures have been fabricated and shown to have efficiencies up to 21.3 percent (1X, AM0), and a GaAs-on-Si cell at 15.2 percent (1X, AM0) is reported. Homoepitaxial n/p InP cells with an efficiency of 18.8 percent (1X, AM0) are also reported. The fabrication of heteroepitaxial InP solar cells with one-sun AM0 efficiency values of 9.4 percent (on GaAs) and 7.2 percent (on Si) is described.

  17. Ultra-Compact High-Efficiency Luminaire for General Illumination

    SciTech Connect

    Lowes, Ted

    2012-04-08

    Cree has developed a new ultra-compact light emitting diode (LED) luminaire capable of providing high efficacy with excellent color quality that can lead to significant energy savings in today's commercial and retail applications. This success was based on an integrated development effort tailoring the LED component characteristics, optics, thermal management and driver design for the small footprint to achieve an overall system efficiency of 70%. A new LED component was designed to provide high brightness and efficacy in a form factor that allowed for a small directional beam with a luminaire housing design able to dissipate the heat effectively using a small physical envelope. A very compact, 90% efficient driver was developed to meet the system performance while not taking away any thermal mass from the heat sink. A 91% efficient secondary optics was designed to maximize efficiency while providing a smooth beam. The reliability of the new LED component was robust under accelerated testing conditions. Luminaires were assembled integrating the novel LED component, secondary optics, heat sink and driver technology to demonstrate the system improvement. Cree has successfully completed this project by developing an ultra-compact LED luminaire that provided 380 lumens at a correlated color temperature (CCT) of 2822 K and color rendering index (CRI) of 94 with an efficacy of 94 lumens per watt (LPW) when operating at 4 W input power (steady state) with an overall system efficiency of 81%. At a higher input power of 9 Watts, the lamp provided 658 lumens at 71 LPW.

  18. Development of a high efficiency thin silicon solar cell

    NASA Technical Reports Server (NTRS)

    Storti, G.; Culik, J.; Wrigley, C.

    1980-01-01

    Significant improvements in open-circuit voltage and conversion efficiency, even on relatively high bulk resistivity silicon, were achieved by using a screen-printed aluminum paste back surface field. A 4 sq cm 50 micron m thick cell was fabricated from textured 10 omega-cm silicon which had an open-circuit voltage of 595 mV and AMO conversion efficiency at 25 C of 14.3%. The best 4 sq cm 50 micron thick cell (2 omega-cm silicon) produced had an open-circuit voltage of 607 mV and an AMO conversion efficiency of 15%. Processing modifications are described which resulted in better front contact integrity and reduced breakage. These modifications were utilized in the thin cell pilot line to fabricate 4 sq cm cells with an average AMO conversion efficiency at 25 C of better than 12.5% and with lot yields as great as 51% of starts; a production rate of 10,000 cells per month was demonstrated. A pilot line was operated which produced large area (25 cm) ultra-thin cells with an average AMO conversion efficiency at 25 deg of better than 11.5% and a lot yield as high as 17%.

  19. Gettering and passivation of high efficiency multicrystalline silicon solar cells

    NASA Astrophysics Data System (ADS)

    Rohatgi, A.; Narasimha, S.; Cai, L.

    1997-02-01

    A detailed study was conducted on aluminum and phosphorus gettering in HEM mc-Si and defect passivation by PECVD SiN in EFG mc-Si to achieve high efficiency solar cells on these promising photovoltaic materials. Solar cells with efficiencies as high as 18.6% (1 cm2 area) were achieved on multicrystalline silicon (mc-Si) grown by the heat exchanger method (HEM) by a process which implements impurity gettering, an effective back surface field, front surface passivation, and forming gas annealing. This represents the highest reported solar cell efficiency on mc-Si to date. PCD analysis revealed that the bulk lifetime in certain HEM samples after phosphorus gettering can be as high as 135 μs. By incorporating a deeper aluminum back surface field (Al-BSF), the back surface recombination velocity (Sb) for 0.65 Ω-cm HEM mc-Si solar cells was lowered from 10,000 cm/s to 2,000 cm/s resulting in the 18.6% efficient device. It was also observed that a screen-printed/RTP alloyed Al-BSF process could raise the efficiency of both float zone and relatively defect-free mc-Si solar cells by lowering Sb. However, this process was found to increase the electrical activity of extended defects so that mc-Si devices with a significant defect density showed an overall degradation in performance. In the case of EFG mc-Si, neural network modeling in conjunction with a study of post deposition annealing was used to provide guidelines for effective defect passivation by PECVD SiN films. Appropriate deposition and annealing conditions resulted in a 45% increase in cell efficiency due to AR coating and another 25-30% increase due to defect passivation by atomic hydrogen.

  20. Improving the efficiency of high purity water systems

    SciTech Connect

    Bukay, M.; Youngberg, D.

    1994-05-01

    High purity water (HPW) production involves the consumption of substantial amounts of energy, precious potable water, harsh/hazardous chemicals, and other environmental/impact materials. The discharge of some of the waste products from HPW systems is also a concern. The purpose of this paper is to discuss techniques to improve the efficiency of HPW production and thereby reduce any negative effects on the environment. It provides specific examples of how end-users and equipment suppliers are increasing the efficiency of their pretreatment, reverse osmosis, ion-exchange, and sanitization technology while frequently citing capital and operating cost reductions.

  1. High efficiency low cost monolithic module for SARSAT distress beacons

    NASA Technical Reports Server (NTRS)

    Petersen, Wendell C.; Siu, Daniel P.

    1992-01-01

    The program objectives were to develop a highly efficient, low cost RF module for SARSAT beacons; achieve significantly lower battery current drain, amount of heat generated, and size of battery required; utilize MMIC technology to improve efficiency, reliability, packaging, and cost; and provide a technology database for GaAs based UHF RF circuit architectures. Presented in viewgraph form are functional block diagrams of the SARSAT distress beacon and beacon RF module as well as performance goals, schematic diagrams, predicted performances, and measured performances for the phase modulator and power amplifier.

  2. Biocleavable Polycationic Micelles as Highly Efficient Gene Delivery Vectors

    NASA Astrophysics Data System (ADS)

    Zhang, Min; Xue, Ya-Nan; Liu, Min; Zhuo, Ren-Xi; Huang, Shi-Wen

    2010-11-01

    An amphiphilic disulfide-containing polyamidoamine was synthesized by Michael-type polyaddition reaction of piperazine to equimolar N, N'-bis(acryloyl)cystamine with 90% yield. The polycationic micelles (198 nm, 32.5 mV), prepared from the amphiphilic polyamidoamine by dialysis method, can condense foreign plasmid DNA to form nanosized polycationic micelles/DNA polyelectrolyte complexes with positive charges, which transfected 293T cells with high efficiency. Under optimized conditions, the transfection efficiencies of polycationic micelles/DNA complexes are comparable to, or even higher than that of commercially available branched PEI (Mw 25 kDa).

  3. High-efficiency heteroepitaxial InP solar cells

    NASA Technical Reports Server (NTRS)

    Wanlass, M. W.; Coutts, T. J.; Ward, J. S.; Emery, K. A.

    1991-01-01

    High-efficiency, thin-film InP solar cells grown heteroepitaxially on GaAs and Si single-crystal bulk substrates are being developed as a means of eliminating the problems associated with using single-crystal InP substrates. A novel device structure employing a compositionally graded Ga(x)In(1-x)As layer between the bulk substrate and the InP cell layers is used to reduce the dislocation density and improve the minority carrier properties in the InP. The structures are grown in a continuous sequence of steps using computer-controlled atmospheric pressure metalorganic vapor phase epitaxy (APMOVPE). Dislocation densities as low as 3 x 10(exp 7) sq cm and minority carrier lifetimes as high as 3.3 ns are achieved in the InP layers with this method using both GaAs or Si substrates. Structures prepared in this fashion are also completely free of microcracks. These results represent a substantial improvement in InP layer quality when compared to heteroepitaxial InP prepared using conventional techniques such as thermally cycled growth and post-growth annealing. The present work is is concerned with the fabrication and characterization of high-efficiency, thin-film InP solar cells. Both one-sun and concentrator cells were prepared for device structures grown on GaAs substrates. One-cell cells have efficiencies as high as 13.7 percent at 25 C. However, results for the concentrator cells are emphasized. The concentrator cell performance is characterized as a function of the air mass zero (AM0) solar concentration ratio and operating temperature. From these data, the temperature coefficients of the cell performance parameters are derived as a function of the concentration ratio. Under concentration, the cells exhibit a dramatic increase in efficiency and an improved temperature coefficient of efficiency. At 25 C, a peak conversion efficiency of 18.9 percent is reported. At 80 C, the peak AM0 efficiency is 15.7 percent at 75.6 suns. These are the highest efficiencies yet

  4. Analytic scaling analysis of high harmonic generation conversion efficiency.

    PubMed

    Falcão-Filho, E L; Gkortsas, M; Gordon, Ariel; Kärtner, Franz X

    2009-06-22

    Closed form expressions for the high harmonic generation (HHG) conversion efficiency are obtained for the plateau and cutoff regions. The presented formulas eliminate most of the computational complexity related to HHG simulations, and enable a detailed scaling analysis of HHG efficiency as a function of drive laser parameters and material properties. Moreover, in the total absence of any fitting procedure, the results show excellent agreement with experimental data reported in the literature. Thus, this paper opens new pathways for the global optimization problem of extreme ultraviolet (EUV) sources based on HHG.

  5. Development of high efficiency (14 percent) solar cell array module

    NASA Technical Reports Server (NTRS)

    Iles, P. A.; Khemthong, S.; Olah, S.; Sampson, W. J.; Ling, K. S.

    1980-01-01

    Most effort was concentrated on development of procedures to provide large area (3 in. diameter) high efficiency (16.5 percent AM1, 28 C) P+NN+ solar cells. Intensive tests with 3 in. slices gave consistently lower efficiency (13.5 percent). The problems were identified as incomplete formation of and optimum back surface field (BSF), and interaction of the BSF process and the shallow P+ junction. The problem was shown not to be caused by reduced quality of silicon near the edges of the larger slices.

  6. High-efficiency, 200 watt, 12-gigahertz traveling wave tube

    NASA Technical Reports Server (NTRS)

    Kosmahl, H. G.; Mcnary, B. D.; Sauseng, O.

    1974-01-01

    Design and performance of a highly efficient experimental 200-watt traveling wave tube for space communications are described. The tube uses a coupled cavity slow wave structure with periodic permanent magnet focusing. A two-step velocity taper is incorporated in the slow wave structure for velocity resynchronization with the modulated beam. The spent beam is reconditioned in a refocusing section before it is collected in a novel multistage depressed collector. The collector is radiation cooled and heat insulated from the tube body. At saturation the tube provides peak output power of 240 watts with a 35-db gain and an overall maximum efficiency of 56 percent.

  7. The National Ignition Facility: A New Era in High Energy Density Science

    SciTech Connect

    Moses, E

    2009-06-10

    The National Ignition Facility, the world's most energetic laser system, is now operational. This talk will describe NIF, the ignition campaign, and new opportunities in fusion energy and high energy density science enabled by NIF.

  8. High Efficiency LED Lamp for Solid-State Lighting

    SciTech Connect

    James Ibbetson

    2006-12-31

    This report contains a summary of technical achievements during a three-year project to demonstrate high efficiency, solid-state lamps based on gallium nitride/silicon carbide light-emitting diodes. Novel chip designs and fabrication processes are described for a new type of nitride light-emitting diode with the potential for very high efficiency. This work resulted in the demonstration of blue light-emitting diodes in the one watt class that achieved up to 495 mW of light output at 350 mA drive current, corresponding to quantum and wall plug efficiencies of 51% and 45%, respectively. When combined with a phosphor in Cree's 7090 XLamp package, these advanced blue-emitting devices resulted in white light-emitting diodes whose efficacy exceeded 85 lumens per watt. In addition, up to 1040 lumens at greater than 85 lumens per watt was achieved by combining multiple devices to make a compact white lamp module with high optical efficiency.

  9. High Efficiency Microwave Power Amplifier: From the Lab to Industry

    NASA Technical Reports Server (NTRS)

    Sims, William Herbert, III; Bell, Joseph L. (Technical Monitor)

    2001-01-01

    Since the beginnings of space travel, various microwave power amplifier designs have been employed. These included Class-A, -B, and -C bias arrangements. However, shared limitation of these topologies is the inherent high total consumption of input power associated with the generation of radio frequency (RF)/microwave power. The power amplifier has always been the largest drain for the limited available power on the spacecraft. Typically, the conversion efficiency of a microwave power amplifier is 10 to 20%. For a typical microwave power amplifier of 20 watts, input DC power of at least 100 watts is required. Such a large demand for input power suggests that a better method of RF/microwave power generation is required. The price paid for using a linear amplifier where high linearity is unnecessary includes higher initial and operating costs, lower DC-to-RF conversion efficiency, high power consumption, higher power dissipation and the accompanying need for higher capacity heat removal means, and an amplifier that is more prone to parasitic oscillation. The first use of a higher efficiency mode of power generation was described by Baxandall in 1959. This higher efficiency mode, Class-D, is achieved through distinct switching techniques to reduce the power losses associated with switching, conduction, and gate drive losses of a given transistor.

  10. Design of precision mounts for optimizing the conversion efficiency of KDP crystals for the National Ignition Facility

    SciTech Connect

    Hibbard, R.L., LLNL

    1998-03-30

    A key design challenge for the National Ignition Facility (NIF), being constructed at Lawrence Livermore National Laboratory (LLNL), [Hibbard, R L , 1998], is the frequency converter consisting of two KDP crystals and a focusing lens Frequency conversion is a critical performance factor for NIF and the optical mount design for this plays a key role in meeting design specifications The frequency converter is a monolithic cell that mounts the optics and is the point on the beamline where the frequency conversion crystals are optimally aligned and the cell is focused on target The lasing medium is neodymium in phosphate glass with a fundamental frequency (1{omega}) of 1 053 {micro}m Sum frequency generation in a pair of conversion crystals (KDP/KD*P) produces 1 8 MJ of the third harmonic light (3{omega} or {lambda}=O 35 pm). The phase-matching scheme on NIF is type I second harmonic generation followed by type II sum-frequency-mixing of the residual fundamental and the second harmonic light This laser unlike previous laser system designs, must achieve high conversion efficiency, 85%, which is close to the 90 8% theoretical maximum As a result, this design is very sensitive to angular variations in beam propagation and in the crystal axes orientation. Factors that influence the phase matching angle include crystal inhomogeneity, residual and induced stress in the crystals, the crystals` natural and mounted surface figure, mounting imperfections and gravity sag These angular variations need to be controlled within a 40 {micro}rad error budget. The optical mount contributions to the angular error budget are 20 {micro}rad and are what make the frequency converter in the Final Optics Cell (FOC) such a challenging precision design. The premise of using full edge support in the FOC design is primarily driven by the spherical target chamber design that has optics mounted at multiple longitudinal angles and thus gravity sag in the crystals that needs to be minimized To meet

  11. High-Adiabat High-Foot Inertial Confinement Fusion Implosion Experiments on the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Park, H.-S.; Hurricane, O. A.; Callahan, D. A.; Casey, D. T.; Dewald, E. L.; Dittrich, T. R.; Döppner, T.; Hinkel, D. E.; Berzak Hopkins, L. F.; Le Pape, S.; Ma, T.; Patel, P. K.; Remington, B. A.; Robey, H. F.; Salmonson, J. D.; Kline, J. L.

    2014-02-01

    This Letter reports on a series of high-adiabat implosions of cryogenic layered deuterium-tritium (DT) capsules indirectly driven by a "high-foot" laser drive pulse at the National Ignition Facility. High-foot implosions have high ablation velocities and large density gradient scale lengths and are more resistant to ablation-front Rayleigh-Taylor instability induced mixing of ablator material into the DT hot spot. Indeed, the observed hot spot mix in these implosions was low and the measured neutron yields were typically 50% (or higher) of the yields predicted by simulation. On one high performing shot (N130812), 1.7 MJ of laser energy at a peak power of 350 TW was used to obtain a peak hohlraum radiation temperature of ˜300 eV. The resulting experimental neutron yield was (2.4±0.05)×1015 DT, the fuel ρR was (0.86±0.063) g/cm2, and the measured Tion was (4.2±0.16) keV, corresponding to 8 kJ of fusion yield, with ˜1/3 of the yield caused by self-heating of the fuel by α particles emitted in the initial reactions. The generalized Lawson criteria, an ignition metric, was 0.43 and the neutron yield was ˜70% of the value predicted by simulations that include α-particle self-heating.

  12. High Quality Down Lighting Luminaire with 73% Overall System Efficiency

    SciTech Connect

    Robert Harrison; Steven C. Allen; Joseph Bernier; Robert Harrison

    2010-08-31

    This report summarizes work to develop a high flux, high efficiency LED-based downlight at OSRAM SYLVANIA under US Department of Energy contract DE-FC26-08NT01582. A new high power LED and electronic driver were developed for these downlights. The LED achieved 100 lumens per watt efficacy and 1700 lumen flux output at a correlated color temperature of 3500K. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.99, and total harmonic distortion <10%. Two styles of downlights using the LED and driver were shown to exceed the project targets for steady-state luminous efficacy and flux of 70 lumens per watt and 1300 lumens, respectively. Compared to similar existing downlights using compact fluorescent or LED sources, these downlights had much higher efficacy at nearly the same luminous flux.

  13. Broadband high-efficiency dielectric metasurfaces for the visible spectrum.

    PubMed

    Devlin, Robert C; Khorasaninejad, Mohammadreza; Chen, Wei Ting; Oh, Jaewon; Capasso, Federico

    2016-09-20

    Metasurfaces are planar optical elements that hold promise for overcoming the limitations of refractive and conventional diffractive optics. Original dielectric metasurfaces are limited to transparency windows at infrared wavelengths because of significant optical absorption and loss at visible wavelengths. Thus, it is critical that new materials and nanofabrication techniques be developed to extend dielectric metasurfaces across the visible spectrum and to enable applications such as high numerical aperture lenses, color holograms, and wearable optics. Here, we demonstrate high performance dielectric metasurfaces in the form of holograms for red, green, and blue wavelengths with record absolute efficiency (>78%). We use atomic layer deposition of amorphous titanium dioxide with surface roughness less than 1 nm and negligible optical loss. We use a process for fabricating dielectric metasurfaces that allows us to produce anisotropic, subwavelength-spaced dielectric nanostructures with shape birefringence. This process is capable of realizing any high-efficiency metasurface optical element, e.g., metalenses and axicons. PMID:27601634

  14. A Perspective on the Future of High Efficiency Engines

    SciTech Connect

    Wagner, Robert M; Curran, Scott; Green Jr, Johney Boyd

    2013-01-01

    New fuel economy standards and emissions regulations are accelerating the development of new engine technologies, sensors, and on-board computing. These developments will enable unprecedented engine control, which will in turn enable real-world implementations of low temperature combustion, high-speed controls, and other high efficiency engine technologies. With this expanded flexibility in engine design and control, the challenge will now be the exponential increase in the design and calibration space and the need for the development of new simulations, optimization methods, and self-learning control methodologies. This manuscript provides historical and future perspectives on the opportunities and challenges of this unparalleled technology growth on the next generation of high efficiency engines.

  15. Broadband high-efficiency dielectric metasurfaces for the visible spectrum.

    PubMed

    Devlin, Robert C; Khorasaninejad, Mohammadreza; Chen, Wei Ting; Oh, Jaewon; Capasso, Federico

    2016-09-20

    Metasurfaces are planar optical elements that hold promise for overcoming the limitations of refractive and conventional diffractive optics. Original dielectric metasurfaces are limited to transparency windows at infrared wavelengths because of significant optical absorption and loss at visible wavelengths. Thus, it is critical that new materials and nanofabrication techniques be developed to extend dielectric metasurfaces across the visible spectrum and to enable applications such as high numerical aperture lenses, color holograms, and wearable optics. Here, we demonstrate high performance dielectric metasurfaces in the form of holograms for red, green, and blue wavelengths with record absolute efficiency (>78%). We use atomic layer deposition of amorphous titanium dioxide with surface roughness less than 1 nm and negligible optical loss. We use a process for fabricating dielectric metasurfaces that allows us to produce anisotropic, subwavelength-spaced dielectric nanostructures with shape birefringence. This process is capable of realizing any high-efficiency metasurface optical element, e.g., metalenses and axicons.

  16. Broadband high-efficiency dielectric metasurfaces for the visible spectrum

    PubMed Central

    Devlin, Robert C.; Khorasaninejad, Mohammadreza; Chen, Wei Ting; Oh, Jaewon; Capasso, Federico

    2016-01-01

    Metasurfaces are planar optical elements that hold promise for overcoming the limitations of refractive and conventional diffractive optics. Original dielectric metasurfaces are limited to transparency windows at infrared wavelengths because of significant optical absorption and loss at visible wavelengths. Thus, it is critical that new materials and nanofabrication techniques be developed to extend dielectric metasurfaces across the visible spectrum and to enable applications such as high numerical aperture lenses, color holograms, and wearable optics. Here, we demonstrate high performance dielectric metasurfaces in the form of holograms for red, green, and blue wavelengths with record absolute efficiency (>78%). We use atomic layer deposition of amorphous titanium dioxide with surface roughness less than 1 nm and negligible optical loss. We use a process for fabricating dielectric metasurfaces that allows us to produce anisotropic, subwavelength-spaced dielectric nanostructures with shape birefringence. This process is capable of realizing any high-efficiency metasurface optical element, e.g., metalenses and axicons. PMID:27601634

  17. Optically Thin Metallic Films for High-Radiative-Efficiency Plasmonics

    NASA Astrophysics Data System (ADS)

    Yang, Yi; Zhen, Bo; Hsu, Chia Wei; Miller, Owen D.; Joannopoulos, John D.; Soljačić, Marin

    2016-07-01

    Plasmonics enables deep-subwavelength concentration of light and has become important for fundamental studies as well as real-life applications. Two major existing platforms of plasmonics are metallic nanoparticles and metallic films. Metallic nanoparticles allow efficient coupling to far field radiation, yet their synthesis typically leads to poor material quality. Metallic films offer substantially higher quality materials, but their coupling to radiation is typically jeopardized due to the large momentum mismatch with free space. Here, we propose and theoretically investigate optically thin metallic films as an ideal platform for high-radiative-efficiency plasmonics. For far-field scattering, adding a thin high-quality metallic substrate enables a higher quality factor while maintaining the localization and tunability that the nanoparticle provides. For near-field spontaneous emission, a thin metallic substrate, of high quality or not, greatly improves the field overlap between the emitter environment and propagating surface plasmons, enabling high-Purcell (total enhancement > $10^4$), high-quantum-yield (> 50 %) spontaneous emission, even as the gap size vanishes (3$\\sim$5 nm). The enhancement has almost spatially independent efficiency and does not suffer from quenching effects that commonly exist in previous structures.

  18. Optically Thin Metallic Films for High-Radiative-Efficiency Plasmonics.

    PubMed

    Yang, Yi; Zhen, Bo; Hsu, Chia Wei; Miller, Owen D; Joannopoulos, John D; Soljačić, Marin

    2016-07-13

    Plasmonics enables deep-subwavelength concentration of light and has become important for fundamental studies as well as real-life applications. Two major existing platforms of plasmonics are metallic nanoparticles and metallic films. Metallic nanoparticles allow efficient coupling to far field radiation, yet their synthesis typically leads to poor material quality. Metallic films offer substantially higher quality materials, but their coupling to radiation is typically jeopardized due to the large momentum mismatch with free space. Here, we propose and theoretically investigate optically thin metallic films as an ideal platform for high-radiative-efficiency plasmonics. For far-field scattering, adding a thin high-quality metallic substrate enables a higher quality factor while maintaining the localization and tunability that the nanoparticle provides. For near-field spontaneous emission, a thin metallic substrate, of high quality or not, greatly improves the field overlap between the emitter environment and propagating surface plasmons, enabling high-Purcell (total enhancement >10(4)), high-quantum-yield (>50%) spontaneous emission, even as the gap size vanishes (3-5 nm). The enhancement has almost spatially independent efficiency and does not suffer from quenching effects that commonly exist in previous structures.

  19. Progress on the XG-III high-intensity laser facility with three synchronized beams

    NASA Astrophysics Data System (ADS)

    Su, Jingqin; Zhu, Qihua; Xie, Na; Zhou, Kainan; Huang, Xiaojun; Zeng, Xiaoming; Wang, Xiao; Wang, Xiaodong; Xie, Xudong; Zhao, Lei; Zuo, Yanlei; Jiang, Dongbin; Sun, Li; Guo, Yi; Zhou, Song; Wen, Jing; Li, Qing; Huang, Zheng; Jiang, Xuejun; Jing, Feng

    2015-02-01

    The paper presents the technical design and progress on a special high-power laser facility, i.e. XG-III, which is being used for high-field physics research and fast ignition research. The laser facility outputs synchronized nanosecond, picosecond and femtosecond beams with three wavelengths, i.e. 527 nm, 1053 nm and 800 nm respectively, and multiple combinations of the beams can be used for physics experiments. The commissioning of the laser facility was completed by the end of 2013. The measurement results show that the main parameters of the three beams are equal to or greater than the designed ones.

  20. Efficiency and Loading Evaluation of High Efficiency Mist Eliminators (HEME) - 12003

    SciTech Connect

    Giffin, Paxton K.; Parsons, Michael S.; Waggoner, Charles A.

    2012-07-01

    High efficiency mist eliminators (HEME) are filters primarily used to remove moisture and/or liquid aerosols from an air stream. HEME elements are designed to reduce aerosol and particulate load on primary High Efficiency Particulate Air (HEPA) filters and to have a liquid particle removal efficiency of approximately 99.5% for aerosols down to sub-micron size particulates. The investigation presented here evaluates the loading capacity of the element in the absence of a water spray cleaning system. The theory is that without the cleaning system, the HEME element will suffer rapid buildup of solid aerosols, greatly reducing the particle loading capacity. Evaluation consists of challenging the element with a waste surrogate dry aerosol and di-octyl phthalate (DOP) at varying intervals of differential pressure to examine the filtering efficiency of three different element designs at three different media velocities. Also, the elements are challenged with a liquid waste surrogate using Laskin nozzles and large dispersion nozzles. These tests allow the loading capacity of the unit to be determined and the effectiveness of washing down the interior of the elements to be evaluated. (authors)

  1. Predicting High Harmonic Ion Cyclotron Heating Efficiency in Tokamak Plasmas

    NASA Astrophysics Data System (ADS)

    Green, D. L.; Berry, L. A.; Chen, G.; Ryan, P. M.; Canik, J. M.; Jaeger, E. F.

    2011-09-01

    Observations of improved radio frequency (rf) heating efficiency in ITER relevant high-confinement (H-)mode plasmas on the National Spherical Tokamak Experiment are investigated by whole-device linear simulation. The steady-state rf electric field is calculated for various antenna spectra and the results examined for characteristics that correlate with observations of improved or reduced rf heating efficiency. We find that launching toroidal wave numbers that give fast-wave propagation in the scrape-off plasma excites large amplitude (˜kVm-1) coaxial standing modes between the confined plasma density pedestal and conducting vessel wall. Qualitative comparison with measurements of the stored plasma energy suggests that these modes are a probable cause of degraded heating efficiency.

  2. Invited Article: Broadband highly efficient dielectric metadevices for polarization control

    NASA Astrophysics Data System (ADS)

    Kruk, Sergey; Hopkins, Ben; Kravchenko, Ivan I.; Miroshnichenko, Andrey; Neshev, Dragomir N.; Kivshar, Yuri S.

    2016-06-01

    Metadevices based on dielectric nanostructured surfaces with both electric and magnetic Mie-type resonances have resulted in the best efficiency to date for functional flat optics with only one disadvantage: a narrow operational bandwidth. Here we experimentally demonstrate broadband transparent all-dielectric metasurfaces for highly efficient polarization manipulation. We utilize the generalized Huygens principle, with a superposition of the scattering contributions from several electric and magnetic multipolar modes of the constituent meta-atoms, to achieve destructive interference in reflection over a large spectral bandwidth. By employing this novel concept, we demonstrate reflectionless (˜90% transmission) half-wave plates, quarter-wave plates, and vector beam q-plates that can operate across multiple telecom bands with ˜99% polarization conversion efficiency.

  3. Predicting high harmonic ion cyclotron heating efficiency in Tokamak plasmas.

    PubMed

    Green, D L; Berry, L A; Chen, G; Ryan, P M; Canik, J M; Jaeger, E F

    2011-09-30

    Observations of improved radio frequency (rf) heating efficiency in ITER relevant high-confinement (H-)mode plasmas on the National Spherical Tokamak Experiment are investigated by whole-device linear simulation. The steady-state rf electric field is calculated for various antenna spectra and the results examined for characteristics that correlate with observations of improved or reduced rf heating efficiency. We find that launching toroidal wave numbers that give fast-wave propagation in the scrape-off plasma excites large amplitude (∼kV m(-1)) coaxial standing modes between the confined plasma density pedestal and conducting vessel wall. Qualitative comparison with measurements of the stored plasma energy suggests that these modes are a probable cause of degraded heating efficiency.

  4. SECOND GENERATION ADVANCED REBURNING FOR HIGH EFFICIENCY NOx CONTROL

    SciTech Connect

    1998-10-30

    This project is designed to develop a family of novel NO{sub x} control technologies, called Second Generation Advanced Reburning which has the potential to achieve 90+% NO{sub x} control in coal fired boilers at a significantly lower cost than SCR. The fourth reporting period in Phase II (July 1--September 30, 1998) included experimental activities at pilot scale and combined chemistry-mixing modeling on gas reburning. The pilot scale tests reported in previous Quarterly Reports QR-2 and QR-3 were continued. The objective was to simulate furnace conditions at the Greenidge boiler No. 6 owned and operated by NYSEG and to improve the process performance. The tests were conducted in EER's Boiler Simulator Facility (BSF). During the reporting period, measurements of CO and ammonia emissions were conducted for reburn + SNCR conditions, as well as tests on the effect of sodium on NO{sub x} control efficiency. Exhaust levels of CO remained below 100 ppm in all tests. Prospective process conditions for the full-scale facility have been identified that can provide over 80% NO{sub x} reduction while maintaining ammonia slip below 4 ppm. Addition of sodium resulted in NO{sub x} control improvement of about 7-10 percentage points. The objective of modeling work was to further understand the influence of the mixing process on gas reburning and to identify factors that can increase the effectiveness of NO reduction. Modeling results demonstrated that the main features of gas reburning could be described using a detailed chemical mechanism with one-dimensional representation of mixing.

  5. High-Efficiency Harmonically Terminated Diode and Transistor Rectifiers

    SciTech Connect

    Roberg, M; Reveyrand, T; Ramos, I; Falkenstein, EA; Popovic, Z

    2012-12-01

    This paper presents a theoretical analysis of harmonically terminated high-efficiency power rectifiers and experimental validation on a class-C single Schottky-diode rectifier and a class-F-1 GaN transistor rectifier. The theory is based on a Fourier analysis of current and voltage waveforms, which arise across the rectifying element when different harmonic terminations are presented at its terminals. An analogy to harmonically terminated power amplifier (PA) theory is discussed. From the analysis, one can obtain an optimal value for the dc load given the RF circuit design. An upper limit on rectifier efficiency is derived for each case as a function of the device on-resistance. Measured results from fundamental frequency source-pull measurement of a Schottky diode rectifier with short-circuit terminations at the second and third harmonics are presented. A maximal device rectification efficiency of 72.8% at 2.45 GHz matches the theoretical prediction. A 2.14-GHz GaN HEMT rectifier is designed based on a class-F-1 PA. The gate of the transistor is terminated in an optimal impedance for self-synchronous rectification. Measurements of conversion efficiency and output dc voltage for varying gate RF impedance, dc load, and gate bias are shown with varying input RF power at the drain. The rectifier demonstrates an efficiency of 85% for a 10-W input RF power at the transistor drain with a dc voltage of 30 V across a 98-Omega resistor.

  6. Design, Fabrication and Test of a High Efficiency Refractive Secondary Concentrator for Solar Applications

    NASA Technical Reports Server (NTRS)

    Wong, Wayne A.; Geng, Steven M.; Castle, Charles H.; Macosko, Robert P.

    2000-01-01

    Common to many of the space applications that utilize solar thermal energy such as electric power conversion, thermal propulsion, and furnaces, is a need for highly efficient, solar concentration systems. An effort is underway to develop the refractive secondary concentrator, which uses refraction and total internal reflection to efficiently concentrate and direct solar energy. When used in combination with advanced primary concentrators, the refractive secondary concentrator enables very high system concentration ratios (10,000 to 1) and very high temperatures (greater than 2000 K). Presented is an overview of the effort at the NASA Glenn Research Center to evaluate the performance of a prototype single crystal sapphire refractive secondary concentrator and to compare the performance with analytical models. The effort involves the design and fabrication of a secondary concentrator, design and fabrication of a calorimeter and its support hardware, calibration of the calorimeter, testing of the secondary concentrator in NASA Glenn's Tank 6 solar thermal vacuum facility, and comparing the test results with predictions. Test results indicate an average throughput efficiency of 87%. It is anticipated that reduction of a known reflection loss with an anti-reflective coating would result in a secondary concentrator throughput efficiency of approximately 93%.

  7. HIGH ENERGY, HIGH BRIGHTNESS X-RAYS PRODUCED BY COMPTON BACKSCATTERING AT THE LIVERMORE PLEIADES FACILITY

    SciTech Connect

    Tremaine, A M; Anderson, S G; Betts, S; Crane, J; Gibson, D J; Hartemann, F V; Jacob, J S; Frigola, P; Lim, J; Rosenzweig, J; Travish, G

    2005-05-19

    PLEIADES (Picosecond Laser Electron Interaction for the Dynamic Evaluation of Structures) produces tunable 30-140 keV x-rays with 0.3-5 ps pulse lengths and up to 10{sup 7} photons/pulse by colliding a high brightness electron beam with a high power laser. The electron beam is created by an rf photo-injector system, accelerated by a 120 MeV linac, and focused to 20 {micro}m with novel permanent magnet quadrupoles. To produce Compton back scattered x-rays, the electron bunch is overlapped with a Ti:Sapphire laser that delivers 500 mJ, 100 fs, pulses to the interaction point. K-edge radiography at 115 keV on Uranium has verified the angle correlated energy spectrum inherent in Compton scattering and high-energy tunability of the Livermore source. Current upgrades to the facility will allow laser pumping of targets synchronized to the x-ray source enabling dynamic diffraction and time-resolved studies of high Z materials. Near future plans include extending the radiation energies to >400 keV, allowing for nuclear fluorescence studies of materials.

  8. Advanced Klystrons for High Efficiency Accelerator Systems - Final Report

    SciTech Connect

    Read, Michael; Ives, Robert Lawrence

    2014-03-26

    This program explored tailoring of RF pulses used to drive accelerator cavities. Simulations indicated that properly shaping the pulse risetime to match accelerator cavity characteristics reduced reflected power and increased total efficiency. Tailoring the pulse requires a high power, gridded, klystron to shape the risetime while also controlling the beam current. The Phase I program generated a preliminary design of a gridded electron gun for a klystron producing 5-10 MW of RF power. This required design of a segmented cathode using Controlled Porosity Reservoir cathodes to limit power deposition on the grid. The program was successful in computationally designing a gun producing a high quality electron beam with grid control. Additional analysis of pulse tailoring indicated that technique would only be useful for cavity drive pulses that were less than approximately 2-3 times the risetime. Otherwise, the efficiency gained during the risetime of the pulse became insignificant when considering the efficiency over the entire pulse. Consequently, it was determined that a Phase II program would not provide sufficient return to justify the cost. Never the less, other applications for a high power gridded gun are currently being pursued. This klystron, for example, would facilitate development inverse Comptom x-ray sources by providing a high repetition rate (10 -100 kHz) RF source.

  9. High-efficiency nanostructured window GaAs solar cells.

    PubMed

    Liang, Dong; Kang, Yangsen; Huo, Yijie; Chen, Yusi; Cui, Yi; Harris, James S

    2013-10-01

    Nanostructures have been widely used in solar cells due to their extraordinary optical properties. In most nanostructured cells, high short circuit current has been obtained due to enhanced light absorption. However, most of them suffer from lowered open circuit voltage and fill factor. One of the main challenges is formation of good junction and electrical contact. In particular, nanostructures in GaAs only have shown unsatisfactory performances (below 5% in energy conversion efficiency) which cannot match their ideal material properties and the record photovoltaic performances in industry. Here we demonstrate a completely new design for nanostructured solar cells that combines nanostructured window layer, metal mesa bar contact with small area, high quality planar junction. In this way, we not only keep the advanced optical properties of nanostructures such as broadband and wide angle antireflection, but also minimize its negative impact on electrical properties. High light absorption, efficient carrier collection, leakage elimination, and good lateral conductance can be simultaneously obtained. A nanostructured window cell using GaAs junction and AlGaAs nanocone window demonstrates 17% energy conversion efficiency and 0.982 V high open circuit voltage.

  10. Scattering Efficiency of High-Voltage Tethers in Space

    NASA Technical Reports Server (NTRS)

    Krivorutsky, E. N.; Khazanov, G. V.; Gamayunov, K. V.; Avanov, L. A.

    2005-01-01

    Several concepts have been proposed to remediate the effect of artificial Radiation Belts (RB) in Space Plasma. Among them is the high-voltage electrostatic tether remediation technique. Preliminary analysis that has been carried out later by several groups showed, that this technique could be very efficient and is able to control relativistic electron energies of artificial RB population. The relativistic electron population is the one of the most important topic of US Space Weather studies and very dangerous to many civilian and military space assets, it is also important to study some fundamentals of scattering efficiency of high-voltage tethers in space plasma. There are several fundamental issues that should be examined in order to validate high-voltage tether artificial RB remediation concept. The most critical among them are: power consumption, the size and stability of the plasma sheath around the tether, and scattering efficiency of this high-voltage system that is ultimately related with the plasma sheath size. This study would be focused on the scattering process itself and artificial RB remediation assuming that power consumption and the size of the plasma sheath are known.

  11. Technology benefits and ground test facilities for high-speed civil transport development

    NASA Technical Reports Server (NTRS)

    Winston, Matthew M.; Shields, Elwood M.; Morris, Shelby J., Jr.

    1992-01-01

    The advanced technology base necessary for successful twenty-first century High-Speed Civil Transport (HSCT) aircraft will require extensive ground testing in aerodynamics, propulsion, acoustics, structures, materials, and other disciplines. This paper analyzes the benefits of advanced technology application to HSCT concepts, addresses the adequacy of existing groundbased test facilities, and explores the need for new facilities required to support HSCT development. A substantial amount of HSCT-related ground testing can be accomplished in existing facilities. The HSCT development effort could also benefit significantly from some new facilities initially conceived for testing in other aeronautical research areas. A new structures testing facility is identified as critically needed to insure timely technology maturation.

  12. Lightweight High Efficiency Electric Motors for Space Applications

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A.; Tyler, Tony R.; Piper, P. J.

    2011-01-01

    Lightweight high efficiency electric motors are needed across a wide range of space applications from - thrust vector actuator control for launch and flight applications to - general vehicle, base camp habitat and experiment control for various mechanisms to - robotics for various stationary and mobile space exploration missions. QM Power?s Parallel Path Magnetic Technology Motors have slowly proven themselves to be a leading motor technology in this area; winning a NASA Phase II for "Lightweight High Efficiency Electric Motors and Actuators for Low Temperature Mobility and Robotics Applications" a US Army Phase II SBIR for "Improved Robot Actuator Motors for Medical Applications", an NSF Phase II SBIR for "Novel Low-Cost Electric Motors for Variable Speed Applications" and a DOE SBIR Phase I for "High Efficiency Commercial Refrigeration Motors" Parallel Path Magnetic Technology obtains the benefits of using permanent magnets while minimizing the historical trade-offs/limitations found in conventional permanent magnet designs. The resulting devices are smaller, lower weight, lower cost and have higher efficiency than competitive permanent magnet and non-permanent magnet designs. QM Power?s motors have been extensively tested and successfully validated by multiple commercial and aerospace customers and partners as Boeing Research and Technology. Prototypes have been made between 0.1 and 10 HP. They are also in the process of scaling motors to over 100kW with their development partners. In this paper, Parallel Path Magnetic Technology Motors will be discussed; specifically addressing their higher efficiency, higher power density, lighter weight, smaller physical size, higher low end torque, wider power zone, cooler temperatures, and greater reliability with lower cost and significant environment benefit for the same peak output power compared to typically motors. A further discussion on the inherent redundancy of these motors for space applications will be provided.

  13. Palladium-catalyzed Br/D exchange of arenes: Selective deuterium incorporation with versatile functional group tolerance and high efficiency

    SciTech Connect

    Zhang, Honghai -Hai; Bonnesen, Peter V.; Hong, Kunlun

    2015-01-01

    There is a facile method for introducing one or more deuterium atoms onto an aromatic nucleus via Br/D exchange with high functional group tolerance and high incorporation efficiency is disclosed. Deuterium-labeled aryl chlorides and aryl borates which could be used as substrates in cross-coupling reactions to construct more complicated deuterium-labeled compounds can also be synthesized by this method.

  14. Test Program for High Efficiency Gas Turbine Exhaust Diffuser

    SciTech Connect

    Norris, Thomas R.

    2009-12-31

    This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of “strutlets” to control stalls on a model diffuser strut. Strutlets are a novel flow-improving vane concept intended to improve the efficiency of flow in turbine exhausts. Strutlets can help reduce turbine back pressure, and incrementally improve turbine efficiency, increase power, and reduce greenhouse gas emmission. The long-term goal is a 0.5 percent improvement of each item, averaged over the US gas turbine fleet. The strutlets were tested in a physical scale model of a gas turbine exhaust diffuser. The test flow passage is a straight, annular diffuser with three sets of struts. At the end of Phase 1, the ability of strutlets to keep flow attached to struts was demonstrated, but the strutlet drag was too high for a net efficiency advantage. An independently sponsored followup project did develop a highly-modified low-drag strutlet. In combination with other flow improving vanes, complicance to the stated goals was demonstrated for for simple cycle power plants, and to most of the goals for combined cycle power plants using this particular exhaust geometry. Importantly, low frequency diffuser noise was reduced by 5 dB or more, compared to the baseline. Appolicability to other diffuser geometries is yet to be demonstrated.

  15. High efficiency GaAs/Ge monolithic tandem solar cells

    NASA Technical Reports Server (NTRS)

    Tobin, S. P.; Vernon, S. M.; Bajgar, C.; Haven, V. E.; Geoffroy, L. M.; Sanfacon, M. M.; Lillington, D. R.; Hart, R. E., Jr.

    1988-01-01

    Two-terminal monolithic tandem cells consisting of a GaAs solar cell grown epitaxially on a Ge solar cell substrate are very attractive for space applications. Tandem cells of GaAs grown by metal-organic chemical vapor deposition on thin Ge were investigated to address both higher efficiency and reduced weight. Two materials growth issues associated with this heteroepitaxial system, autodoping of the GaAs layers by Ge and diffusion of Ga and As into the Ge substrate, were addressed. The latter appears to result in information of an unintentional p-n junction in the Ge. Early simulator measurements gave efficiencies as high as 21.7 percent for 4 cm2 GaAs/Ge cells, but recent high-altitude testing has given efficiencies of 18 percent. Sources of errors in simulator measurements of two-terminal tandem cells are discussed. A limiting efficiency of about 36 percent for the tandem cell at AMO was calculated. Ways to improve the performance of present cells, primarily by increasing the Isc and Voc of the Ge cell, are proposed.

  16. Efficiency Analysis of a High-Specific Impulse Hall Thruster

    NASA Technical Reports Server (NTRS)

    Jacobson, David (Technical Monitor); Hofer, Richard R.; Gallimore, Alec D.

    2004-01-01

    Performance and plasma measurements of the high-specific impulse NASA-173Mv2 Hall thruster were analyzed using a phenomenological performance model that accounts for a partially-ionized plasma containing multiply-charged ions. Between discharge voltages of 300 to 900 V, the results showed that although the net decrease of efficiency due to multiply-charged ions was only 1.5 to 3.0 percent, the effects of multiply-charged ions on the ion and electron currents could not be neglected. Between 300 to 900 V, the increase of the discharge current was attributed to the increasing fraction of multiply-charged ions, while the maximum deviation of the electron current from its average value was only +5/-14 percent. These findings revealed how efficient operation at high-specific impulse was enabled through the regulation of the electron current with the applied magnetic field. Between 300 to 900 V, the voltage utilization ranged from 89 to 97 percent, the mass utilization from 86 to 90 percent, and the current utilization from 77 to 81 percent. Therefore, the anode efficiency was largely determined by the current utilization. The electron Hall parameter was nearly constant with voltage, decreasing from an average of 210 at 300 V to an average of 160 between 400 to 900 V. These results confirmed our claim that efficient operation can be achieved only over a limited range of Hall parameters.

  17. Wide-Band, High-Quantum-Efficiency Photodetector

    NASA Technical Reports Server (NTRS)

    Jackson, Deborah; Wilson, Daniel; Stern, Jeffrey

    2007-01-01

    A design has been proposed for a photodetector that would exhibit a high quantum efficiency (as much as 90 percent) over a wide wavelength band, which would typically be centered at a wavelength of 1.55 m. This and similar photodetectors would afford a capability for detecting single photons - a capability that is needed for research in quantum optics as well as for the practical development of secure optical communication systems for distribution of quantum cryptographic keys. The proposed photodetector would be of the hot-electron, phonon-cooled, thin-film superconductor type. The superconducting film in this device would be a meandering strip of niobium nitride. In the proposed photodetector, the quantum efficiency would be increased through incorporation of optiA design has been proposed for a photodetector that would exhibit a high quantum efficiency (as much as 90 percent) over a wide wavelength band, which would typically be centered at a wavelength of 1.55 m. This and similar photodetectors would afford a capability for detecting single photons - a capability that is needed for research in quantum optics as well as for the practical development of secure optical communication systems for distribution of quantum cryptographic keys. The proposed photodetector would be of the hot-electron, phonon-cooled, thin-film superconductor type. The superconducting film in this device would be a meandering strip of niobium nitride. In the proposed photodetector, the quantum efficiency would be increased through incorporation of opti-

  18. Laser doping for high-efficiency silicon solar cells

    NASA Astrophysics Data System (ADS)

    Jäger, Ulrich; Wolf, Andreas; Steinhauser, Bernd; Benick, Jan; Nekarda, Jan; Preu, Ralf

    2012-10-01

    Selective laser doping is a versatile tool for the local adaption of doping profiles in a silicon substrate. By adjusting the laser fluence as well as the pulse width the maximum melt depth in the silicon can be controlled. Longer pulses lead to lower temperatures in the material and can help to enlarge the process window as ablation sets in at higher fluencies. For the fabrication of highly efficient silicon solar cells, laser doping can be used for efficiency improvement and process simplification. In passivated emitter and rear cells (PERC), selective laser doping can be used for selective emitter formation. Employing such a process, an efficiency boost of Δ ƞ= 0.4%abs was observed on commercial Cz-Si material. Laser doping was also used for process simplification for the fabrication of locally doped point contacts at the rear of a solar cell. A simple approach employing a doped passivation layer and a laser doping process allows for efficiencies beyond 22% on high quality n-type silicon.

  19. High-efficiency solar cell and method for fabrication

    DOEpatents

    Hou, Hong Q.; Reinhardt, Kitt C.

    1999-01-01

    A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD).

  20. High-efficiency solar cell and method for fabrication

    DOEpatents

    Hou, H.Q.; Reinhardt, K.C.

    1999-08-31

    A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD). 4 figs.

  1. High voltage generator circuit with low power and high efficiency applied in EEPROM

    NASA Astrophysics Data System (ADS)

    Yan, Liu; Shilin, Zhang; Yiqiang, Zhao

    2012-06-01

    This paper presents a low power and high efficiency high voltage generator circuit embedded in electrically erasable programmable read-only memory (EEPROM). The low power is minimized by a capacitance divider circuit and a regulator circuit using the controlling clock switch technique. The high efficiency is dependent on the zero threshold voltage (Vth) MOSFET and the charge transfer switch (CTS) charge pump. The proposed high voltage generator circuit has been implemented in a 0.35 μm EEPROM CMOS process. Measured results show that the proposed high voltage generator circuit has a low power consumption of about 150.48 μW and a higher pumping efficiency (83.3%) than previously reported circuits. This high voltage generator circuit can also be widely used in low-power flash devices due to its high efficiency and low power dissipation.

  2. High-efficiency silicon heterojunction solar cells: Status and perspectives

    SciTech Connect

    De Wolf, S.

    2015-04-27

    Silicon heterojunction technology (HJT) uses silicon thin-film deposition techniques to fabricate photovoltaic devices from mono-crystalline silicon wafers (c-Si). This enables energy-conversion efficiencies above 21 %, also at industrial-production level. In this presentation we review the present status of this technology and point out recent trends. We first discuss how the properties of thin hydrogenated amorphous silicon (a-Si:H) films can be exploited to fabricate passivating contacts, which is the key to high- efficiency HJT solar cells. Such contacts enable very high operating voltages, approaching the theoretical limits, and yield small temperature coefficients. With this approach, an increasing number of groups are reporting devices with conversion efficiencies well over 20 % on n-type wafers, Panasonic leading the field with 24.7 %. Exciting results have also been obtained on p-type wafers. Despite these high voltages, important efficiency gains can still be made in fill factor and optical design. This requires improved understanding of carrier transport across device interfaces and reduced parasitic absorption in HJT solar cells. For the latter, several strategies can be followed: Short- wavelength losses can be reduced by replacing the front a-Si:H films with wider-bandgap window layers, such as silicon alloys or even metal oxides. Long-wavelength losses are mitigated by introducing new high-mobility TCO’s such as hydrogenated indium oxide, and also by designing new rear reflectors. Optical shadow losses caused by the front metalisation grid are significantly reduced by replacing printed silver electrodes with fine-line plated copper contacts, leading also to possible cost advantages. The ultimate approach to minimize optical losses is the implementation of back-contacted architectures, which are completely devoid of grid shadow losses and parasitic absorption in the front layers can be minimized irrespective of electrical transport requirements. The

  3. High-efficiency silicon heterojunction solar cells: Status and perspectives

    SciTech Connect

    De Wolf, S.; Geissbuehler, J.; Loper, P.; Martin de Nicholas, S.; Seif, J.; Tomasi, A.; Ballif, C.

    2015-05-11

    Silicon heterojunction technology (HJT) uses silicon thin-film deposition techniques to fabricate photovoltaic devices from mono-crystalline silicon wafers (c-Si). This enables energy-conversion efficiencies above 21 %, also at industrial-production level. In this presentation we review the present status of this technology and point out recent trends. We first discuss how the properties of thin hydrogenated amorphous silicon (a-Si:H) films can be exploited to fabricate passivating contacts, which is the key to high- efficiency HJT solar cells. Such contacts enable very high operating voltages, approaching the theoretical limits, and yield small temperature coefficients. With this approach, an increasing number of groups are reporting devices with conversion efficiencies well over 20 % on both-sides contacted n-type cells, Panasonic leading the field with 24.7 %. Exciting results have also been obtained on p-type wafers. Despite these high voltages, important efficiency gains can still be made in fill factor and optical design. This requires improved understanding of carrier transport across device interfaces and reduced parasitic absorption in HJT solar cells. For the latter, several strategies can be followed: Short-wavelength losses can be reduced by replacing the front a-Si:H films with wider-bandgap window layers, such as silicon alloys or even metal oxides. Long- wavelength losses are mitigated by introducing new high-mobility TCO’s such as hydrogenated indium oxide, and also by designing new rear reflectors. Optical shadow losses caused by the front metallization grid are significantly reduced by replacing printed silver electrodes with fine-line plated copper contacts, leading also to possible cost advantages. The ultimate approach to minimize optical losses is the implementation of back-contacted architectures, which are completely devoid of grid shadow losses and parasitic absorption in the front layers can be minimized irrespective of electrical

  4. [Efficiencies of contamination source for flooring and some materials used in unencapsulated radioactivity handling facilities].

    PubMed

    Yoshida, M; Yoshizawa, M; Minami, K

    1990-09-01

    The efficiencies of contamination source, defined in ISO Report 7506-1, were experimentally determined for such materials as flooring, polyethylene, smear-tested filter paper and stainless steel plate. 5 nuclides of 147Pm, 60Co, 137Cs, 204Tl and 90Sr-Y were used to study beta-ray energy dependence of the efficiency, and 241Am as alpha-ray emitter. The charge-up effect in the measurement by a window-less 2 pi-proportional counter was evaluated to obtain reliable surface emission rate. The measured efficiencies for non-permeable materials, except for two cases, are more than 0.5 even for 147Pm. The ISO recommendations were shown to be conservative enough on the basis of present results.

  5. DOE/Industrial Technologies Program DOE Award Number DE-FG36-05GO15099 Plant Wide Energy Efficiency Assessment Pilgrims Pride Corporation – Mt Pleasant Facility

    SciTech Connect

    Paper, Riyaz; Dooley, Bill; Turpish, William J; Symonds, Mark; Carswell, Needham

    2007-04-13

    areas for detailed analysis, perform a detailed analysis for several of the opportunities identified, and support the development of an energy strategy for the facility. The team consisted of Pace Global Energy Services, LLC; Hudson Technologies Company; Rocky Research, Inc.; and W.J. Turpish and Associates. The project used a systematic approach to complete a plant-wide energy efficiency assessment at the Mt Pleasant Facility. Major energy consuming equipment and processes were determined and opportunities for high annual savings potential were targeted for further evaluation. Exhibit 1 below summarizes the major savings opportunities at the site. The total energy savings represent 14% of the energy consumed on site on an MMBtu basis, with 12% of total energy savings achievable in projects with less than a two year payback. Pace Global Energy Services, LLC of Fairfax, Virginia provided the analysis of departmental energy use, identification of areas for detailed analysis, and support for the development of an energy strategy for the facility. Hudson Technologies Company analyzed the combustion and steam systems to identify opportunities for economic heat recovery and improvement in boiler operations. Rocky Research, Inc analyzed the refrigeration systems and W.J. Turpish and Associates reviewed the cooling towers and evaporative condensers.

  6. Efficient frequency doubler for the soft X-ray SASE FEL at the TESLA Test Facility

    NASA Astrophysics Data System (ADS)

    Feldhaus, J.; Körfer, M.; Möller, T.; Pflüger, J.; Saldin, E. L.; Schneidmiller, E. A.; Yurkov, M. V.

    2004-08-01

    This paper describes an effective frequency doubler scheme for SASE free electron lasers (FEL). It consists of an undulator tuned to the first harmonic, a dispersion section, and a tapered undulator tuned to the second harmonic. The first stage is a conventional soft X-ray SASE FEL. Its gain is controlled in such a way that the maximum energy modulation of the electron beam at the exit is about equal to the local energy spread, but still far away from saturation. When the electron bunch passes through the dispersion section this energy modulation leads to effective compression of the particles. Then the bunched electron beam enters the tapered undulator and produces strong radiation in the process of coherent deceleration. We demonstrate a frequency doubler scheme that can be integrated into the SASE FEL at the TESLA Test Facility at DESY, and will allow to reach 3 nm wavelength with GW-level of output peak power. This would extend the operating range of the FEL into the so-called water window and significantly expand the capabilities of the TTF FEL user facility.

  7. The high efficiency steel filters for nuclear air cleaning

    SciTech Connect

    Bergman, W.; Larsen, G.; Lopez, R.; Williams, K.; Violet, C.

    1990-08-01

    We have, in cooperation with industry, developed high-efficiency filters made from sintered stainless-steel fibers for use in several air-cleaning applications in the nuclear industry. These filters were developed to overcome the failure modes in present high-efficiency particulate air (HEPA) filters. HEPA filters are made from glass paper and glue, and they may fail when they get hot or wet and when they are overpressured. In developing our steel filters, we first evaluated the commercially available stainless-steel filter media made from sintered powder and sintered fiber. The sintered-fiber media performed much better than sintered-powder media, and the best media had the smallest fiber diameter. Using the best media, we then built prototype filters for venting compressed gases and evaluated them in our automated filter tester. 12 refs., 20 figs.

  8. Blanket options for high-efficiency fusion power

    SciTech Connect

    Usher, J L; Lazareth, O W; Fillo, J A; Horn, F L; Powell, J R

    1980-01-01

    The efficiencies of blankets for fusion reactors are usually in the range of 30 to 40%, limited by the operating temperatures (500/sup 0/C) of conventional structural materials such as stainless steels. In this project two-zone blankets are proposed; these blankets consist of a low-temperature shell surrounding a high-temperature interior zone. A survey of nucleonics and thermal hydraulic parameters has led to a reference blanket design consisting of a water-cooled stainless steel shell around a BeO, ZrO/sub 2/ interior (cooled by argon) utilizing Li/sub 2/O for tritium breeding. In this design, approximately 60% of the fusion energy is deposited in the high-temperature interior. The maximum argon temperature is 2230/sup 0/C leading to an overall efficiency estimate of 55 to 60% for this reference case.

  9. Highly efficient reflective Dammann grating with a triangular structure.

    PubMed

    Wang, Jin; Zhou, Changhe; Ma, Jianyong; Zong, Yonghong; Jia, Wei

    2016-07-01

    A highly efficient reflective Dammann grating with a triangular structure operating at 1064 nm wavelength under normal incidence for TE polarization is designed and fabricated. Rigorous coupled wave analysis and particle swarm optimization algorithms are adopted to design and analyze the properties. The triangular reflective grating could cancel the 0th order, and the mechanism is clarified by the simplified modal method. The gratings are fabricated by direct laser writing lithography. The diffraction efficiency of fabricated grating is more than 86% at 1064 nm wavelength (97.6% in theory). This reflective grating should be a useful optical element in the field of high-power lasers as well as other reflective applications. PMID:27409211

  10. High Energy-Efficiency Retrofits to Baltimore's Row Homes

    SciTech Connect

    Chalk, J.; Johnson, A.L.; Lipscomb, L.; Wendt, R.

    1999-04-19

    The purpose of the research project is to develop high-perfommnce, energy-eflicient retrofits of existing row homes in Baltimore, Maryland. These efficiency enhancements are to optimize building envelope improvements, mechanical equipment improvements and operational improvements to the highest cost-effective level. Furthermore, this project is to investigate and demonstrate the impact of high-performance energy-efficiency retrofit improvements on row homes in the Historic East area of Baltimore. Three homes awaiting renovation are planned to receive building envelope, mechanical system, and electrical system improvements that will improve their energy petiormance. An incremental additional cost ceiling of $4000 for the energy eftlciency improvements, beyond those normally installed, has been set by the project.

  11. Development of high-efficiency solar cells on silicon web

    NASA Technical Reports Server (NTRS)

    Meier, D. L.; Greggi, J.; Rai-Choudhury, P.

    1986-01-01

    Work is reported aimed at identifying and reducing sources of carrier recombination both in the starting web silicon material and in the processed cells. Cross-sectional transmission electron microscopy measurements of several web cells were made and analyzed. The effect of the heavily twinned region on cell efficiency was modeled, and the modeling results compared to measured values for processed cells. The effects of low energy, high dose hydrogen ion implantation on cell efficiency and diffusion length were examined. Cells were fabricated from web silicon known to have a high diffusion length, with a new double layer antireflection coating being applied to these cells. A new contact system, to be used with oxide passivated cells and which greatly reduces the area of contact between metal and silicon, was designed. The application of DLTS measurements to beveled samples was further investigated.

  12. High efficiency thin-film GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Zwerdling, S.; Wang, K. L.; Yeh, Y. C. M.

    1981-01-01

    The paper demonstrates the feasibility of producing high-efficiency GaAs solar cells with high power-to-weight ratios by organic metallic chemical vapor deposition (OM-CVD) growth of thin epi-layers on suitable substrates. An AM1 conversion efficiency of 18% (14% AM0), or 17% (13% AM0) with a 5% grid coverage is achieved for a single-crystal GaAs n(+)/p cell grown by OM-CVD on a Ge wafer. Thin GaAs epi-layers OM-CVD grown can be fabricated with good crystallographic quality using a Si-substrate on which a thin Ge epi-interlayer is first deposited by CVD from GeH4 and processed for improved surface morphology

  13. High-efficiency GaAs concentrator space cells

    NASA Technical Reports Server (NTRS)

    Werthen, J. G.; Virshup, G. F.; Macmillan, H. F.; Ford, C. W.; Hamaker, H. C.

    1987-01-01

    High efficiency Al sub x Ga sub 1-x As/GaAs heteroface solar concentrator cells have been developed for space applications. The cells, which were grown using metalorganic chemical vapor deposition (MOCVD), have been fabricated in both the p-n and n-p configurations. Magnesium and zinc are used as the p-type dopants, and Se is used as the n-type dopant. The space cells, which are designed for use in a Cassegrainian concentrator operating at 100 suns, AMO, have a circular illuminated area 4 mm in diameter on a 5 mm by 5 mm cell. These cells have exhibited flash-tested efficiencies as high as 23.6 percent at 28 C and 21.6 percent at 80 C.

  14. Highly Efficient Perovskite Solar Cells with Tunable Structural Color

    PubMed Central

    2015-01-01

    The performance of perovskite solar cells has been progressing over the past few years and efficiency is likely to continue to increase. However, a negative aspect for the integration of perovskite solar cells in the built environment is that the color gamut available in these materials is very limited and does not cover the green-to-blue region of the visible spectrum, which has been a big selling point for organic photovoltaics. Here, we integrate a porous photonic crystal (PC) scaffold within the photoactive layer of an opaque perovskite solar cell following a bottom-up approach employing inexpensive and scalable liquid processing techniques. The photovoltaic devices presented herein show high efficiency with tunable color across the visible spectrum. This now imbues the perovskite solar cells with highly desirable properties for cladding in the built environment and encourages design of sustainable colorful buildings and iridescent electric vehicles as future power generation sources. PMID:25650872

  15. High resolution PET breast imager with improved detection efficiency

    DOEpatents

    Majewski, Stanislaw

    2010-06-08

    A highly efficient PET breast imager for detecting lesions in the entire breast including those located close to the patient's chest wall. The breast imager includes a ring of imaging modules surrounding the imaged breast. Each imaging module includes a slant imaging light guide inserted between a gamma radiation sensor and a photodetector. The slant light guide permits the gamma radiation sensors to be placed in close proximity to the skin of the chest wall thereby extending the sensitive region of the imager to the base of the breast. Several types of photodetectors are proposed for use in the detector modules, with compact silicon photomultipliers as the preferred choice, due to its high compactness. The geometry of the detector heads and the arrangement of the detector ring significantly reduce dead regions thereby improving detection efficiency for lesions located close to the chest wall.

  16. Modelling and fabrication of high-efficiency silicon solar cells

    SciTech Connect

    Rohatgi, A.; Smith, A.W.; Salami, J.

    1991-10-01

    This report covers the research conducted on modelling and development of high-efficiency silicon solar cells during the period May 1989 to August 1990. First, considerable effort was devoted toward developing a ray-tracing program for the photovoltaic community to quantify and optimize surface texturing for solar cells. Second, attempts were made to develop a hydrodynamic model for device simulation. Such a model is somewhat slower than drift-diffusion type models like PC-1D, but it can account for more physical phenomena in the device, such as hot carrier effects, temperature gradients, thermal diffusion, and lattice heat flow. In addition, Fermi-Dirac statistics have been incorporated into the model to deal with heavy doping effects more accurately. Third and final component of the research includes development of silicon cell fabrication capabilities and fabrication of high-efficiency silicon cells. 84 refs., 46 figs., 10 tabs.

  17. Highly efficient perovskite solar cells with tunable structural color.

    PubMed

    Zhang, Wei; Anaya, Miguel; Lozano, Gabriel; Calvo, Mauricio E; Johnston, Michael B; Míguez, Hernán; Snaith, Henry J

    2015-03-11

    The performance of perovskite solar cells has been progressing over the past few years and efficiency is likely to continue to increase. However, a negative aspect for the integration of perovskite solar cells in the built environment is that the color gamut available in these materials is very limited and does not cover the green-to-blue region of the visible spectrum, which has been a big selling point for organic photovoltaics. Here, we integrate a porous photonic crystal (PC) scaffold within the photoactive layer of an opaque perovskite solar cell following a bottom-up approach employing inexpensive and scalable liquid processing techniques. The photovoltaic devices presented herein show high efficiency with tunable color across the visible spectrum. This now imbues the perovskite solar cells with highly desirable properties for cladding in the built environment and encourages design of sustainable colorful buildings and iridescent electric vehicles as future power generation sources.

  18. High-efficiency multi-colored photovoltaic cells

    NASA Astrophysics Data System (ADS)

    Hovel, H. J.

    1983-09-01

    The objective of this project was to explore tandem/solar cell structures and methods to produce them. One was made with amorphous Si on crystalline Si. Other combinations of well-established materials such as Ge, Si, GaAs, and GaAiAs have a potential of producing solar cell efficiency in a high range (30 to 50%). The theoretical performances of several material combinations were computed under single load operation, and the effects of series and shunt resistances are shown. Computations also were made of optimal optical coatings and ohmic grid designs that are needed to construct high efficiency working devices. The epitaxial growth of GaAs, Ge AlAs and Si are then described for use in several configurations. Additionally, measurements of individual solar cells and tandem solar cells at several suns intensity (starting at one sun) are described.

  19. Development of an improved high efficiency thin silicon solar cell

    NASA Technical Reports Server (NTRS)

    Wrigley, C.; Storti, G.

    1978-01-01

    Efforts were directed towards investigating means of producing more effective high-low junctions at the back of the cell. Cells with output power up to 77 mW (AM0 efficiency of 14.2 percent) were fabricated. Some reflectivity studies were also made. Deliveries of 2 cm x 2 cm experimental cells included a number having AM0 outputs greater than 70 mW.

  20. Highly efficient electron vortex beams generated by nanofabricated phase holograms

    SciTech Connect

    Grillo, Vincenzo; Mafakheri, Erfan; Frabboni, Stefano

    2014-01-27

    We propose an improved type of holographic-plate suitable for the shaping of electron beams. The plate is fabricated by a focused ion beam on a silicon nitride membrane and introduces a controllable phase shift to the electron wavefunction. We adopted the optimal blazed-profile design for the phase hologram, which results in the generation of highly efficient (25%) electron vortex beams. This approach paves the route towards applications in nano-scale imaging and materials science.

  1. HEPA (high efficiency particulate air) filter optimization/implementation

    SciTech Connect

    Nenni, J.A.

    1988-02-10

    Prefilters were installed in high efficiency particularly air (HEPA) filter plenums at the Rocky Flats Plant. It was determined that prefiltration systems would extend the life of first-stage HEPA filters and reduce the amount of HEPA filter waste in the transuranic waste category. A remote handling system was designed to remove prefilters without entry into the plenum to reduce secondary waste and decrease exposure to Filter Technicians. 3 figs., 4 tabs.

  2. Chemical beam epitaxy for high efficiency photovoltaic devices

    NASA Technical Reports Server (NTRS)

    Bensaoula, A.; Freundlich, A.; Vilela, M. F.; Medelci, N.; Renaud, P.

    1994-01-01

    InP-based multijunction tandem solar cells show great promise for the conversion efficiency (eta) and high radiation resistance. InP and its related ternary and quanternary compound semiconductors such as InGaAs and InGaAsP offer desirable combinations for energy bandgap values which are very suitable for multijunction tandem solar cell applications. The monolithically integrated InP/In(0.53)Ga(0.47)As tandem solar cells are expected to reach efficiencies above 30 percent. Wanlass, et.al., have reported AMO efficiencies as high as 20.1% for two terminal cells fabricated using atmospheric-pressure metalorganic vapor phase epitaxy (APMOVPE). The main limitations in their technique are first related to the degradation of the intercell ohmic contact (IOC), in this case the In(0.53)Ga(0.47)As tunnel junction during the growth of the top InP subcell structure, and second to the current matching, often limited by the In(0.53)Ga(0.47)As bottom subcell. Chemical beam epitaxy (CBE) has been shown to allow the growth of high quality materials with reproducible complex compositional and doping profiles. The main advantage of CBE compared to metalorganic chemical vapor deposition (MOCVD), the most popular technique for InP-based photovoltaic device fabrication, is the ability to grow high purity epilayers at much lower temperatures (450 C - 530 C). In a recent report it was shown that cost-wise CBE is a breakthrough technology for photovoltaic (PV) solar energy progress in the energy conversion efficiency of InP-based solar cells fabricated using chemical beam epitaxy. This communication summarizes our recent results on PV devices and demonstrates the strength of this new technology.

  3. Flexible, highly efficient all-polymer solar cells

    PubMed Central

    Kim, Taesu; Kim, Jae-Han; Kang, Tae Eui; Lee, Changyeon; Kang, Hyunbum; Shin, Minkwan; Wang, Cheng; Ma, Biwu; Jeong, Unyong; Kim, Taek-Soo; Kim, Bumjoon J.

    2015-01-01

    All-polymer solar cells have shown great potential as flexible and portable power generators. These devices should offer good mechanical endurance with high power-conversion efficiency for viability in commercial applications. In this work, we develop highly efficient and mechanically robust all-polymer solar cells that are based on the PBDTTTPD polymer donor and the P(NDI2HD-T) polymer acceptor. These systems exhibit high power-conversion efficiency of 6.64%. Also, the proposed all-polymer solar cells have even better performance than the control polymer-fullerene devices with phenyl-C61-butyric acid methyl ester (PCBM) as the electron acceptor (6.12%). More importantly, our all-polymer solar cells exhibit dramatically enhanced strength and flexibility compared with polymer/PCBM devices, with 60- and 470-fold improvements in elongation at break and toughness, respectively. The superior mechanical properties of all-polymer solar cells afford greater tolerance to severe deformations than conventional polymer-fullerene solar cells, making them much better candidates for applications in flexible and portable devices. PMID:26449658

  4. Telescoping Solar Array Concept for Achieving High Packaging Efficiency

    NASA Technical Reports Server (NTRS)

    Mikulas, Martin; Pappa, Richard; Warren, Jay; Rose, Geoff

    2015-01-01

    Lightweight, high-efficiency solar arrays are required for future deep space missions using high-power Solar Electric Propulsion (SEP). Structural performance metrics for state-of-the art 30-50 kW flexible blanket arrays recently demonstrated in ground tests are approximately 40 kW/cu m packaging efficiency, 150 W/kg specific power, 0.1 Hz deployed stiffness, and 0.2 g deployed strength. Much larger arrays with up to a megawatt or more of power and improved packaging and specific power are of interest to mission planners for minimizing launch and life cycle costs of Mars exploration. A new concept referred to as the Compact Telescoping Array (CTA) with 60 kW/cu m packaging efficiency at 1 MW of power is described herein. Performance metrics as a function of array size and corresponding power level are derived analytically and validated by finite element analysis. Feasible CTA packaging and deployment approaches are also described. The CTA was developed, in part, to serve as a NASA reference solar array concept against which other proposed designs of 50-1000 kW arrays for future high-power SEP missions could be compared.

  5. 4-GHz high-efficiency broadband FET power amplifiers

    NASA Astrophysics Data System (ADS)

    Chou, S.; Chang, C.

    1982-11-01

    The development and performance of a 4-GHz high-efficiency broadband FET power amplifier module for use in communications satellite transponders is discussed. The design, which is based on the parameters of a commercially available 7.2-mm multicell FET device, was optimized by the use of a CAD program, with broader bandwidth achieved by the addition of two open stubs to the input matching circuit. Six single-ended amplifier modules have been fabricated, tuned and tested, two being high-gain, 17.5% bandwidth designs and four being lower-gain, 25% bandwidth designs. The higher-gain modules, with a 0.5-dB bandwidth of 700 MHz (3.6 to 4.3 GHz) show a 6-dB gain and 3.23-W output power at the maximum efficiency of 48.6%, while broadband modules (0.5-dB bandwidth 900 MHz) deliver 5-W RF power at the maximum efficiency of 36%. The high-performance amplifiers may thus be used in satellite solid-state power amplifiers as replacements for traveling wave tubes.

  6. High efficiency neutron sensitive amorphous silicon pixel detectors

    SciTech Connect

    Mireshghi, A.; Cho, G.; Drewery, J.S.; Hong, W.S.; Jing, T.; Lee, H.; Kaplan, S.N.; Perez-Mendez, V.

    1993-11-01

    A multi-layer a-Si:H based thermal neutron detector was designed, fabricated and simulated by Monte Carlo method. The detector consists of two PECVD deposited a-Si:H pin detectors interfaced with coated layers of Gd, as a thermal neutron converter. Simulation results indicate that a detector consisting of 2 Gd films with thicknesses of 2 and 4 {mu}m, sandwiched properly with two layers of sufficiently thick ({approximately}30{mu}m) amorphous silicon diodes, has the optimum parameters. The detectors have an intrinsic efficiency of about 42% at a threshold setting of 7000 electrons, with an expected average signal size of {approximately}12000 electrons which is well above the noise. This efficiency will be further increased to nearly 63%, if we use Gd with 50% enrichment in {sup 157}Gd. We can fabricate position sensitive detectors with spatial resolution of 300 {mu}m with gamma sensitivity of {approximately}1 {times} 10{sup {minus}5}. These detectors are highly radiation resistant and are good candidates for use in various application, where high efficiency, high resolution, gamma insensitive position sensitive neutron detectors are needed.

  7. Flexible, highly efficient all-polymer solar cells.

    PubMed

    Kim, Taesu; Kim, Jae-Han; Kang, Tae Eui; Lee, Changyeon; Kang, Hyunbum; Shin, Minkwan; Wang, Cheng; Ma, Biwu; Jeong, Unyong; Kim, Taek-Soo; Kim, Bumjoon J

    2015-01-01

    All-polymer solar cells have shown great potential as flexible and portable power generators. These devices should offer good mechanical endurance with high power-conversion efficiency for viability in commercial applications. In this work, we develop highly efficient and mechanically robust all-polymer solar cells that are based on the PBDTTTPD polymer donor and the P(NDI2HD-T) polymer acceptor. These systems exhibit high power-conversion efficiency of 6.64%. Also, the proposed all-polymer solar cells have even better performance than the control polymer-fullerene devices with phenyl-C61-butyric acid methyl ester (PCBM) as the electron acceptor (6.12%). More importantly, our all-polymer solar cells exhibit dramatically enhanced strength and flexibility compared with polymer/PCBM devices, with 60- and 470-fold improvements in elongation at break and toughness, respectively. The superior mechanical properties of all-polymer solar cells afford greater tolerance to severe deformations than conventional polymer-fullerene solar cells, making them much better candidates for applications in flexible and portable devices.

  8. High efficiency of collisional Penrose process requires heavy particle production

    NASA Astrophysics Data System (ADS)

    Ogasawara, Kota; Harada, Tomohiro; Miyamoto, Umpei

    2016-02-01

    The center-of-mass energy of two particles can become arbitrarily large if they collide near the event horizon of an extremal Kerr black hole, which is called the Bañados-Silk-West effect. We consider such a high-energy collision of two particles which started from infinity and follow geodesics in the equatorial plane and investigate the energy extraction from such a high-energy particle collision and the production of particles in the equatorial plane. We analytically show that, on the one hand, if the produced particles are as massive as the colliding particles, the energy-extraction efficiency is bounded by 2.19 approximately. On the other hand, if a very massive particle is produced as a result of the high-energy collision, which has negative energy and necessarily falls into the black hole, the upper limit of the energy-extraction efficiency is increased to (2 +√{3 })2≃13.9 . Thus, higher efficiency of the energy extraction, which is typically as large as 10, provides strong evidence for the production of a heavy particle.

  9. Flexible, highly efficient all-polymer solar cells

    NASA Astrophysics Data System (ADS)

    Kim, Taesu; Kim, Jae-Han; Kang, Tae Eui; Lee, Changyeon; Kang, Hyunbum; Shin, Minkwan; Wang, Cheng; Ma, Biwu; Jeong, Unyong; Kim, Taek-Soo; Kim, Bumjoon J.

    2015-10-01

    All-polymer solar cells have shown great potential as flexible and portable power generators. These devices should offer good mechanical endurance with high power-conversion efficiency for viability in commercial applications. In this work, we develop highly efficient and mechanically robust all-polymer solar cells that are based on the PBDTTTPD polymer donor and the P(NDI2HD-T) polymer acceptor. These systems exhibit high power-conversion efficiency of 6.64%. Also, the proposed all-polymer solar cells have even better performance than the control polymer-fullerene devices with phenyl-C61-butyric acid methyl ester (PCBM) as the electron acceptor (6.12%). More importantly, our all-polymer solar cells exhibit dramatically enhanced strength and flexibility compared with polymer/PCBM devices, with 60- and 470-fold improvements in elongation at break and toughness, respectively. The superior mechanical properties of all-polymer solar cells afford greater tolerance to severe deformations than conventional polymer-fullerene solar cells, making them much better candidates for applications in flexible and portable devices.

  10. Efficient Hole-Transporting Materials with Triazole Core for High-Efficiency Perovskite Solar Cells.

    PubMed

    Choi, Hyeju; Jo, Hyeonjun; Paek, Sanghyun; Koh, Kyungkuk; Ko, Haye Min; Lee, Jae Kwan; Ko, Jaejung

    2016-02-18

    Efficient hole-transporting materials (HTMs), TAZ-[MeOTPA]2 and TAZ-[MeOTPATh]2 incorporating two electron-rich diphenylamino side arms, through direct linkage or thiophen bridges, respectively, on the C3- and C5-positions of a 4-phenyl-1,2,4-triazole core were synthesized. These synthetic HTMs with donor-acceptor type molecular structures exhibited effective intramolecular charge transfer for improving the hole-transporting properties. The structural modification of HTMs by thiophene bridging might increase intermolecular π-π stacking in the solid state and afford a better spectral response because of their increased π-conjugation length. Perovskite-based cells using TAZ-[MeOTPA]2 and TAZ-[MeOTPATh]2 as HTMs afforded high power conversion efficiencies of 10.9 % and 14.4 %, respectively, showing a photovoltaic performance comparable to that obtained using spiro-OMeTAD. These synthetically simple and inexpensive HTMs hold promise for replacing the more expensive spiro-OMeTAD in high-efficiency perovskite solar cells. PMID:26573775

  11. High-Efficiency Absorber for Damping the Transverse Wake Fields

    SciTech Connect

    Novokhatski, A.; Seeman, J.; Weathersby, S.; /SLAC

    2007-02-28

    Transverse wake fields generated by intense beams may propagate long distances in the vacuum chamber and dissipate power in different shielded elements such as bellows, vacuum valves or vacuum pumps. Induced heating in these elements may be high enough to deteriorate vacuum conditions. We have developed a broadband water-cooled bellows-absorber to capture and damp these harmful transverse fields without impacting the longitudinal beam impedance. Experimental results at the PEP-II SLAC B-factory demonstrate high efficiency of this device. This absorber may be useful in other machines like synchrotron light sources or International Linear Collider.

  12. High-efficiency absorber for damping transverse wakefields

    NASA Astrophysics Data System (ADS)

    Novokhatski, A.; Seeman, J.; Weathersby, S.

    2007-04-01

    Transverse wakefields generated by intense beams may propagate long distances in a vacuum chamber and dissipate power in different shielded elements such as bellows, vacuum valves, or vacuum pumps. Induced heating in these elements may be high enough to deteriorate vacuum conditions. We have developed a broadband water-cooled bellows absorber to capture and damp these harmful transverse fields without impacting the longitudinal beam impedance. Experimental results at the PEP-II SLAC B-factory demonstrate a high efficiency for this device. This absorber may be useful in super B-factories, the International Linear Collider, the Large Hadron Collider, or synchrotron light sources.

  13. High efficiency, low cost thin GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Fan, J. C. C.

    1982-01-01

    The feasibility of fabricating space-resistant, high efficiency, light-weight, low-cost GaAs shallow-homojunction solar cells for space application is demonstrated. This program addressed the optimal preparation of ultrathin GaAs single-crystal layers by AsCl3-GaAs-H2 and OMCVD process. Considerable progress has been made in both areas. Detailed studies on the AsCl3 process showed high-quality GaAs thin layers can be routinely grown. Later overgrowth of GaAs by OMCVD has been also observed and thin FaAs films were obtained from this process.

  14. The National Ignition Facility and the Golden Age of High Energy Density Science

    SciTech Connect

    Meier, W; Moses, E I; Newton, M

    2007-09-27

    The National Ignition Facility (NIF) is a 192-beam Nd:glass laser facility being constructed at the Lawrence Livermore National Laboratory (LLNL) to conduct research in inertial confinement fusion (ICF) and high energy density (HED) science. When completed, NIF will produce 1.8 MJ, 500 TW of ultraviolet light, making it the world's largest and highest-energy laser system. The NIF is poised to become the world's preeminent facility for conducting ICF and fusion energy research and for studying matter at extreme densities and temperatures.

  15. High efficiency CIP 10-I personal inhalable aerosol sampler

    NASA Astrophysics Data System (ADS)

    Görner, P.; Wrobel, R.; Simon, X.

    2009-02-01

    The CIP 10 personal aerosol sampler was first developed by Courbon for sampling the respirable fraction of mining dust. This respirable aerosol sampler was further improved by Fabries, then selectors for sampling thoracic and inhalable aerosols were designed. Kenny et al. evaluated the particle-size dependent sampling efficiency of the inhalable version in a large-scale wind tunnel using a life-size dummy. The authors found that the overall sampling efficiency decreases more rapidly than the CEN-ISO-ACGIH target efficiency curve. Görner and Witschger measured the aspiration efficiency of the CIP 10 omni-directional inlet. They found that the aspiration efficiency was high enough for inhalable aerosol sampling. This result led to the conclusion that the low sampling efficiency is due to some internal losses of the aspirated particles before they reach the final sampling stage, namely the CIP 10 rotating filter. Based on the assumption that the inhalable particles are selected at selector aspiration level, an experimental research project was conducted to improve particle transmission to the collection stage of the sampler. Two different inhalable selectors were designed by Görner and tested in a laboratory wind tunnel. The transmission efficiency of both models was measured by Roger following an experimental protocol described by Witschger. The T-shaped air flow circuit was finally adopted to draw the aspirated particles into the final collection stage of the CIP 10. Actually, in this selector, the almost horizontally aspirated particles should be conducted vertically to the rotating cup. In two previous prototypes, particles could be deposited in certain places by inertia (where the aerosol was forced to deviate drastically) or by sedimentation (where the aerosol decelerated). The aerodynamic behaviour of the adopted solution causes the particles to accelerate radially between two horizontal plates before they enter a vertical tube. This acceleration avoids the

  16. Highly Efficient Thermoresponsive Nanocomposite for Controlled Release Applications.

    PubMed

    Yassine, Omar; Zaher, Amir; Li, Er Qiang; Alfadhel, Ahmed; Perez, Jose E; Kavaldzhiev, Mincho; Contreras, Maria F; Thoroddsen, Sigurdur T; Khashab, Niveen M; Kosel, Jurgen

    2016-01-01

    Highly efficient magnetic release from nanocomposite microparticles is shown, which are made of Poly (N-isopropylacrylamide) hydrogel with embedded iron nanowires. A simple microfluidic technique was adopted to fabricate the microparticles with a high control of the nanowire concentration and in a relatively short time compared to chemical synthesis methods. The thermoresponsive microparticles were used for the remotely triggered release of Rhodamine (B). With a magnetic field of only 1 mT and 20 kHz a drug release of 6.5% and 70% was achieved in the continuous and pulsatile modes, respectively. Those release values are similar to the ones commonly obtained using superparamagnetic beads but accomplished with a magnetic field of five orders of magnitude lower power. The high efficiency is a result of the high remanent magnetization of the nanowires, which produce a large torque when exposed to a magnetic field. This causes the nanowires to vibrate, resulting in friction losses and heating. For comparison, microparticles with superparamagnetic beads were also fabricated and tested; while those worked at 73 mT and 600 kHz, no release was observed at the low field conditions. Cytotoxicity assays showed similar and high cell viability for microparticles with nanowires and beads. PMID:27335342

  17. Highly Efficient Thermoresponsive Nanocomposite for Controlled Release Applications

    NASA Astrophysics Data System (ADS)

    Yassine, Omar; Zaher, Amir; Li, Er Qiang; Alfadhel, Ahmed; Perez, Jose E.; Kavaldzhiev, Mincho; Contreras, Maria F.; Thoroddsen, Sigurdur T.; Khashab, Niveen M.; Kosel, Jurgen

    2016-06-01

    Highly efficient magnetic release from nanocomposite microparticles is shown, which are made of Poly (N-isopropylacrylamide) hydrogel with embedded iron nanowires. A simple microfluidic technique was adopted to fabricate the microparticles with a high control of the nanowire concentration and in a relatively short time compared to chemical synthesis methods. The thermoresponsive microparticles were used for the remotely triggered release of Rhodamine (B). With a magnetic field of only 1 mT and 20 kHz a drug release of 6.5% and 70% was achieved in the continuous and pulsatile modes, respectively. Those release values are similar to the ones commonly obtained using superparamagnetic beads but accomplished with a magnetic field of five orders of magnitude lower power. The high efficiency is a result of the high remanent magnetization of the nanowires, which produce a large torque when exposed to a magnetic field. This causes the nanowires to vibrate, resulting in friction losses and heating. For comparison, microparticles with superparamagnetic beads were also fabricated and tested; while those worked at 73 mT and 600 kHz, no release was observed at the low field conditions. Cytotoxicity assays showed similar and high cell viability for microparticles with nanowires and beads.

  18. Highly Efficient Thermoresponsive Nanocomposite for Controlled Release Applications

    PubMed Central

    Yassine, Omar; Zaher, Amir; Li, Er Qiang; Alfadhel, Ahmed; Perez, Jose E.; Kavaldzhiev, Mincho; Contreras, Maria F.; Thoroddsen, Sigurdur T.; Khashab, Niveen M.; Kosel, Jurgen

    2016-01-01

    Highly efficient magnetic release from nanocomposite microparticles is shown, which are made of Poly (N-isopropylacrylamide) hydrogel with embedded iron nanowires. A simple microfluidic technique was adopted to fabricate the microparticles with a high control of the nanowire concentration and in a relatively short time compared to chemical synthesis methods. The thermoresponsive microparticles were used for the remotely triggered release of Rhodamine (B). With a magnetic field of only 1 mT and 20 kHz a drug release of 6.5% and 70% was achieved in the continuous and pulsatile modes, respectively. Those release values are similar to the ones commonly obtained using superparamagnetic beads but accomplished with a magnetic field of five orders of magnitude lower power. The high efficiency is a result of the high remanent magnetization of the nanowires, which produce a large torque when exposed to a magnetic field. This causes the nanowires to vibrate, resulting in friction losses and heating. For comparison, microparticles with superparamagnetic beads were also fabricated and tested; while those worked at 73 mT and 600 kHz, no release was observed at the low field conditions. Cytotoxicity assays showed similar and high cell viability for microparticles with nanowires and beads. PMID:27335342

  19. Facile Synthesis of Single Crystal Vanadium Disulfide Nanosheets by Chemical Vapor Deposition for Efficient Hydrogen Evolution Reaction.

    PubMed

    Yuan, Jiangtan; Wu, Jingjie; Hardy, Will J; Loya, Philip; Lou, Minhan; Yang, Yingchao; Najmaei, Sina; Jiang, Menglei; Qin, Fan; Keyshar, Kunttal; Ji, Heng; Gao, Weilu; Bao, Jiming; Kono, Junichiro; Natelson, Douglas; Ajayan, Pulickel M; Lou, Jun

    2015-10-01

    A facile chemical vapor deposition method to prepare single-crystalline VS2 nanosheets for the hydrogen evolution reaction is reported. The electrocatalytic hydrogen evolution reaction (HER) activities of VS2 show an extremely low overpotential of -68 mV at 10 mA cm(-2), small Tafel slopes of ≈34 mV decade(-1), as well as high stability, demonstrating its potential as a candidate non-noble-metal catalyst for the HER. PMID:26293810

  20. Facile Synthesis of Single Crystal Vanadium Disulfide Nanosheets by Chemical Vapor Deposition for Efficient Hydrogen Evolution Reaction.

    PubMed

    Yuan, Jiangtan; Wu, Jingjie; Hardy, Will J; Loya, Philip; Lou, Minhan; Yang, Yingchao; Najmaei, Sina; Jiang, Menglei; Qin, Fan; Keyshar, Kunttal; Ji, Heng; Gao, Weilu; Bao, Jiming; Kono, Junichiro; Natelson, Douglas; Ajayan, Pulickel M; Lou, Jun

    2015-10-01

    A facile chemical vapor deposition method to prepare single-crystalline VS2 nanosheets for the hydrogen evolution reaction is reported. The electrocatalytic hydrogen evolution reaction (HER) activities of VS2 show an extremely low overpotential of -68 mV at 10 mA cm(-2), small Tafel slopes of ≈34 mV decade(-1), as well as high stability, demonstrating its potential as a candidate non-noble-metal catalyst for the HER.