National Library of Energy BETA

Sample records for alpha emitting isotopes

  1. Direct analysis of air filter samples for alpha emitting isotopes

    SciTech Connect (OSTI)

    Mohagheghi, A.H.; Ghanbari, F.; Ebara, S.B.; Enghauser, M.E. [Sandia National Labs., Albuquerque, NM (United States); Bakhtiar, S.N. [Westinghouse WIPP, Carlsbad, NM (United States)

    1997-04-01

    The traditional method for determination of alpha emitting isotopes on air filters has been to process the samples by radiochemical methods. However, this method is too slow for cases of incidents involving radioactive materials where the determination of personnel received dose is urgent. A method is developed to directly analyze the air filters taken from personal and area air monitors. The site knowledge is used in combination with alpha spectral information to identify isotopes. A mathematical function is developed to estimate the activity for each isotope. The strengths and weaknesses of the method are discussed.

  2. Alpha-emitting isotopes and chromium in a coastal California aquifer Jill N. Densmore a,

    E-Print Network [OSTI]

    .epa.gov/drink/contaminants/#List, accessed December 3, 2013). Understanding the chemistry and distribution of isotopes within the uranium) of 15 pCi/L, when adjusted for uranium activity; there is concern that new wells in the area may exceed-dependent water-quality data collected from the wells in 2011 (with analyses for isotopes within the uranium

  3. Constraining Reionization with Lyman Alpha Emitting Galaxies

    E-Print Network [OSTI]

    Dijkstra, Mark

    2015-01-01

    Neutral diffuse intergalactic gas that existed during the Epoch of Reionization (EoR) suppresses Lyman Alpha (Lya) flux emitted by background galaxies. In this chapter I summarise the increasing observational support for the claim that Lya photons emitted by galaxies at z>6 are suppressed by intervening HI gas. I describe key physical processes that affect Lya transfer during the EoR. I argue that in spite of the uncertainties associated with this complex multiscale problem, the data on Lya emitting galaxies at z=0-6 strongly suggests that the observed reduction in Lya flux from galaxies at z>6 is due to additional intervening HI gas. The main question is what fraction of this additional HI gas is in the diffuse neutral IGM. I summarise how future surveys on existing and upcoming instruments are expected to reduce existing observational uncertainties enormously. With these improved data we will likely be able to nail down reionization with Lya emitting galaxies.

  4. THE SPATIALLY RESOLVED H{alpha}-EMITTING WIND STRUCTURE OF P CYGNI

    SciTech Connect (OSTI)

    Balan, Aurelian; Tycner, C. [Department of Physics, Central Michigan University, Mount Pleasant, MI 48859 (United States); Zavala, R. T.; Benson, J. A.; Hutter, D. J. [US Naval Observatory, Flagstaff Station, 10391 W. Naval Observatory Rd., Flagstaff, AZ 86001 (United States); Templeton, M., E-mail: abalan@delta.ed, E-mail: c.tycner@cmich.ed, E-mail: bzavala@nofs.navy.mi, E-mail: jbenson@nofs.navy.mi, E-mail: djh@nofs.navy.mi, E-mail: matthewt@aavso.or [American Association of Variable Star Observers, 49 Bay State Road, Cambridge, MA 02138 (United States)

    2010-06-15

    High spatial resolution observations of the H{alpha}-emitting wind structure associated with the luminous blue variable star P Cygni were obtained with the Navy Prototype Optical Interferometer. These observations represent the most comprehensive interferometric data set on P Cyg to date. We demonstrate how the apparent size of the H{alpha}-emitting region of the wind structure of P Cyg compares between the 2005, 2007, and 2008 observing seasons and how this relates to the H{alpha} line spectroscopy. Using the data sets from 2005, 2007, and 2008 observing seasons, we fit a circularly symmetric Gaussian model to the interferometric signature from the H{alpha}-emitting wind structure of P Cyg. Based on our results, we conclude that the radial extent of the H{alpha}-emitting wind structure around P Cyg is stable at the 10% level. We also show how the radial distribution of the H{alpha} flux from the wind structure deviates from a Gaussian shape, whereas a two-component Gaussian model is sufficient to fully describe the H{alpha}-emitting region around P Cyg.

  5. New experimental limits on the alpha decays of lead isotopes

    E-Print Network [OSTI]

    J. W. Beeman; F. Bellini; L. Cardani; N. Casali; S. Di Domizio; E. Fiorini; L. Gironi; S. S. Nagorny; S. Nisi; F. Orio; L. Pattavina; G. Pessina; G. Piperno; S. Pirro; E. Previtali; C. Rusconi; C. Tomei; M. Vignati

    2012-12-12

    For the first time a PbWO4 crystal was grown using ancient Roman lead and it was run as a cryogenic detector. Thanks to the simultaneous and independent read-out of heat and scintillation light, the detector was able to discriminate beta/gamma interactions with respect to alpha particles down to low energies. New more stringent limits on the alpha decays of the lead isotopes are presented. In particular a limit of T_{1/2} > 1.4*10^20 y at a 90% C.L. was evaluated for the alpha decay of 204Pb to 200Hg.

  6. A single-particle/single-cell microbeam based on an isotopic alpha source

    E-Print Network [OSTI]

    the alpha particles are emitted to 4p and an acceptance of 10 mrad lm for the ion op- tics (see below) we

  7. Measurement of (alpha,n) reaction cross sections of erbium isotopes for testing astrophysical rate predictions

    E-Print Network [OSTI]

    G. G Kiss; T. Szücs; T. Rauscher; Zs Török; L. Csedreki; Zs Fülöp; Gy Gyürky; Z. Halász

    2015-03-06

    The $\\gamma$-process in core-collapse and/or type Ia supernova explosions is thought to explain the origin of the majority of the so-called $p$ nuclei (the 35 proton-rich isotopes between Se and Hg). Reaction rates for $\\gamma$-process reaction network studies have to be predicted using Hauser-Feshbach statistical model calculations. Recent investigations have shown problems in the prediction of $\\alpha$-widths at astrophysical energies which are an essential input for the statistical model. It has an impact on the reliability of abundance predictions in the upper mass range of the $p$ nuclei. With the measurement of the $^{164,166}$Er($\\alpha$,n)$^{167,169}$Yb reaction cross sections at energies close to the astrophysically relevant energy range we tested the recently suggested low energy modification of the $\\alpha$+nucleus optical potential in a mass region where $\\gamma$-process calculations exhibit an underproduction of the $p$ nuclei. Using the same optical potential for the $\\alpha$-width which was derived from combined $^{162}$Er($\\alpha$,n) and $^{162}$Er($\\alpha$,$\\gamma$) measurement makes it plausible that a low-energy modification of the optical $\\alpha$+nucleus potential is needed.

  8. Measurement and analysis of. cap alpha. particles emitted in reactions of /sup 12/C bombarding /sup 12/C, /sup 27/Al, and /sup nat/Ca

    SciTech Connect (OSTI)

    XIE Yuan-xiang; WU Guo-hua; ZHU Yong-tai; MIAO Rong-zhi; FONG En-pu; YIN Xu; MIAO He-bing; CAI Jing-xiang; SHEN Wen-qing; SUN Shu-ming

    1985-10-01

    The energy spectra and angular distributions of the ..cap alpha.. particles emitted in the reactions of 69.5 MeV /sup 12/C bombarding /sup 12/C, /sup 27/Al, and /sup nat/Ca have been measured and analyzed using the fast-particle exciton model. The contribution from the equilibrium and pre-equilibrium ..cap alpha.. emissions is calculated to be 89%, 81%, and 83% of the total ..cap alpha.. yields for the three reactions, respectively, where the pre-equilibrium ..cap alpha.. emissions are 11%, 14%, and 16%, respectively. A small contribution comes from other reaction mechanisms.

  9. Activities of ?-ray emitting isotopes in rainwater from Greater Sudbury, Canada following the Fukushima incident

    E-Print Network [OSTI]

    B. T. Cleveland; F. A. Duncan; I. T. Lawson; N. J. T. Smith; E. Vazquez-Jauregui

    2012-02-29

    We report the activity measured in rainwater samples collected in the Greater Sudbury area of eastern Canada on 3, 16, 20, and 26 April 2011. The samples were gamma-ray counted in a germanium detector and the isotopes 131I and 137Cs, produced by the fission of 235U, and 134Cs, produced by neutron capture on 133Cs, were observed at elevated levels compared to a reference sample of ice-water. These elevated activities are ascribed to the accident at the Fukushima Dai-ichi nuclear reactor complex in Japan that followed the 11 March earthquake and tsunami. The activity levels observed at no time presented health concerns.

  10. First measurement of several $?$-delayed neutron emitting isotopes beyond N=126

    E-Print Network [OSTI]

    R. Caballero-Folch; C. Domingo-Pardo; J. Agramunt; A. Algora; F. Ameil; A. Arcones; Y. Ayyad; J. Benlliure; I. N. Borzov; M. Bowry; F. Calvino; D. Cano-Ott; G. Cortés; T. Davinson; I. Dillmann; A. Estrade; A. Evdokimov; T. Faestermann; F. Farinon; D. Galaviz; A. R. García; H. Geissel; W. Gelletly; R. Gernhäuser; M. B. Gómez-Hornillos; C. Guerrero; M. Heil; C. Hinke; R. Knöbel; I. Kojouharov; J. Kurcewicz; N. Kurz; Y. Litvinov; L. Maier; J. Marganiec; T. Marketin; M. Marta; T. Martínez; G. Martínez-Pinedo; F. Montes; I. Mukha; D. R. Napoli; C. Nociforo; C. Paradela; S. Pietri; Zs. Podolyák; A. Prochazka; S. Rice; A. Riego; B. Rubio; H. Schaffner; Ch. Scheidenberger; K. Smith; E. Sokol; K. Steiger; B. Sun; J. L. Taín; M. Takechi; D. Testov; H. Weick; E. Wilson; J. S. Winfield; R. Wood; P. Woods; A. Yeremin

    2015-11-04

    The $\\beta$-delayed neutron emission probabilities of neutron rich Hg and Tl nuclei have been measured together with $\\beta$-decay half-lives for 20 isotopes of Au, Hg, Tl, Pb and Bi in the mass region N$\\gtrsim$126. These are the heaviest species where neutron emission has been observed so far. These measurements provide key information to evaluate the performance of nuclear microscopic and phenomenological models in reproducing the high-energy part of the $\\beta$-decay strength distribution. In doing so, it provides important constraints to global theoretical models currently used in $r$-process nucleosynthesis.

  11. Isotopes

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

    Nuclear Physics Isotopes Isotopes Isotopes produced at Los Alamos National Laboratory are saving lives, advancing cutting-edge research and keeping the U.S. safe. Get Expertise...

  12. Measurement of alpha-induced reaction cross sections on erbium isotopes for ? process studies

    SciTech Connect (OSTI)

    Kiss, G. G.; Szücs, T.; Török, Zs.; Fülöp, Zs.; Gyürky, Gy.; Halász, Z.; Somorjai, E. [Institute for Nuclear Research (MTA Atomki), H-4001 Debrecen, POB.51 (Hungary); Rauscher, T. [Centre for Astrophysics Research, School of Physics, Astronomy and Mathematics, University of Hertfordshire, Hatfield AL10 9AB (United Kingdom)

    2014-05-02

    The cross sections of the {sup 162}Er(?,?){sup 166}Yb and {sup 162,164,166}Er(?,n){sup 165,167,169}Yb reactions have been measured at MTA Atomki. The radiative alpha capture reaction cross section was measured between E{sub c.m.} = 11.21 MeV and E{sub c.m.} = 16.09 MeV just above the astrophysically relevant energy region (which lies between 7.8 and 11.48 MeV at T{sub 9} = 3 GK). The {sup 162}Er(?,n){sup 165}Yb, {sup 164}Er(?,n){sup 167}Yb and {sup 166}Er(?,n){sup 169}Yb reactions were studied between E{sub c.m.} = 12.19 and 16.09 MeV, E{sub c.m.} = 13.17 and 16.59 MeV and E{sub c.m.} = 12.68 and 17.08 MeV, respectively. The aim of this work is to provide experimental data for modeling the ? process which is thought to be responsible for the production of the proton-rich isotopes heavier than iron.

  13. Systematic trends in beta-delayed particle emitting nuclei: The case of beta-p-alpha emission from 21Mg

    E-Print Network [OSTI]

    M. V. Lund; M. J. G. Borge; J. A. Briz; J. Cederkäll; H. O. U. Fynbo; J. H. Jensen; B. Jonson; K. L. Laursen; T. Nilsson; A. Perea; V. Pesudo; K. Riisager; O. Tengblad

    2015-06-12

    We have observed beta+-delayed alpha and p-alpha emission from the proton-rich nucleus 21Mg produced at the ISOLDE facility at CERN. The assignments were cross-checked with a time distribution analysis. This is the third identified case of beta-p-alpha emission. We discuss the systematic of beta-delayed particle emission decays, show that our observed decays fit naturally into the existing pattern, and argue that the patterns are to a large extent caused by odd-even effects.

  14. RAPID DETERMINATION OF 237 NP AND PU ISOTOPES IN WATER BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY

    SciTech Connect (OSTI)

    Maxwell, S.; Jones, V.; Culligan, B.; Nichols, S.; Noyes, G.

    2010-06-23

    A new method that allows rapid preconcentration and separation of plutonium and neptunium in water samples was developed for the measurement of {sup 237}Np and Pu isotopes by inductively-coupled plasma mass spectrometry (ICP-MS) and alpha spectrometry; a hybrid approach. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via peak tailing. The method provide enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then moving Pu to DGA resin for additional removal of uranium. The decontamination factor for uranium from Pu is almost 100,000 and the decontamination factor for U from Np is greater than 10,000. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration is performed using a streamlined calcium phosphate precipitation method. Purified solutions are split between ICP-MS and alpha spectrometry so that long and short-lived Pu isotopes can be measured successfully. The method allows for simultaneous extraction of 20 samples (including QC samples) in 4 to 6 hours, and can also be used for emergency response. {sup 239}Pu, {sup 242}Pu and {sup 237}Np were measured by ICP-MS, while {sup 236}Pu, {sup 238}Pu, and {sup 239}Pu were measured by alpha spectrometry.

  15. Production of the Alpha-Particle Emitting Radionuclide Astatine-211 at the Texas A&M Cyclotron Institute 

    E-Print Network [OSTI]

    Bhakta, Viharkumar Satish

    2011-10-21

    current throughout the experiment. Figure 9 displays an enclosed external target system prepared for bombardment. A close-circuit camera system was utilized to monitor the alpha-particle beam before commencement of bombardment. 26 Figure 7... ............................................................................. 28 2.6 Gamma-ray Spectroscopy .................................................................... 35 2.7 Neutron Production .............................................................................. 39 3. RESULTS AND DISCUSSION...

  16. Stark broadening for diagnostics of the electron density in non-equilibrium plasma utilizing isotope hydrogen alpha lines

    SciTech Connect (OSTI)

    Yang, Lin; Tan, Xiaohua; Wan, Xiang; Chen, Lei; Jin, Dazhi; Qian, Muyang; Li, Gongping

    2014-04-28

    Two Stark broadening parameters including FWHM (full width at half maximum) and FWHA (full width at half area) of isotope hydrogen alpha lines are simultaneously introduced to determine the electron density of a pulsed vacuum arc jet. To estimate the gas temperature, the rotational temperature of the C{sub 2} Swan system is fit to 2500?±?100?K. A modified Boltzmann-plot method with b{sub i}-factor is introduced to determine the modified electron temperature. The comparison between results of atomic and ionic lines indicates the jet is in partial local thermodynamic equilibrium and the electron temperature is close to 13?000?±?400?K. Based on the computational results of Gig-Card calculation, a simple and precise interpolation algorithm for the discrete-points tables can be constructed to obtain the traditional n{sub e}-T{sub e} diagnostic maps of two Stark broadening parameters. The results from FWHA formula by the direct use of FWHM?=?FWHA and these from the diagnostic map are different. It can be attributed to the imprecise FWHA formula form and the deviation between FWHM and FWHA. The variation of the reduced mass pair due to the non-equilibrium effect contributes to the difference of the results derived from two hydrogen isotope alpha lines. Based on the Stark broadening analysis in this work, a corrected method is set up to determine n{sub e} of (1.10?±?0.08)?×?10{sup 21}?m{sup ?3}, the reference reduced mass ?{sub 0} pair of (3.30?±?0.82 and 1.65?±?0.41), and the ion kinetic temperature of 7900?±?1800?K.

  17. Lyman-Alpha Emitting Galaxies as a Probe of Reionization: Large-Scale Bubble Morphology and Small-Scale Absorbers

    E-Print Network [OSTI]

    Kakiichi, Koki; Ciardi, Benedetta; Graziani, Luca

    2015-01-01

    The visibility of LyA emitting galaxies during the Epoch of Reionization is controlled by both diffuse HI patches in large-scale bubble morphology and small-scale absorbers. To investigate the impact on LyA photons, we apply a novel combination of analytic and numerical calculations to three scenarios: (i) the `bubble' model, where only diffuse HI outside ionized bubbles is present; (ii) the `web' model, where HI exists only in overdense self-shielded gas; and (iii) the more realistic 'web-bubble' model, which contains both. Our analysis confirms that there is a degeneracy between the ionization structure of the intergalactic medium (IGM) and the HI fraction inferred from LyA surveys, as the three models suppress LyA flux equally with very different HI fractions. We argue that a joint analysis of the LyA luminosity function and the rest-frame equivalent width distribution/LyA fraction can break this degeneracy and provide constraints on the reionization history and its topology. We further show that constrain...

  18. Anisotropic alpha decay from oriented odd-mass isotopes of some light actinides

    SciTech Connect (OSTI)

    Berggren, T. )

    1994-11-01

    Half-lives and anisotropies in the [alpha] decay of [sup 205,207,209]Rn, [sup 219]Rn, [sup 221]Fr, [sup 227,229]Pa, and [sup 229]U have been calculated using the reaction-theoretical formalism proposed by Jackson and Rhoades-Brown and adapted for axially symmetric deformed nuclei by Berggren and Olanders. The possibility of octupole deformation has been taken into account. In addition, a variant of triaxial octupole deformation has been considered tentatively in the case of [sup 227]Pa and [sup 229]Pa.

  19. Activities of \\gamma-ray emitting isotopes in rainwater from Greater Sudbury, Canada following the Fukushima incident

    E-Print Network [OSTI]

    Cleveland, B T; Lawson, I T; Smith, N J T; Vazquez-Jauregui, E

    2012-01-01

    We report the activity measured in rainwater samples collected in the Greater Sudbury area of eastern Canada on 3, 16, 20, and 26 April 2011. The samples were gamma-ray counted in a germanium detector and the isotopes 131I and 137Cs, produced by the fission of 235U, and 134Cs, produced by neutron capture on 133Cs, were observed at elevated levels compared to a reference sample of ice-water. These elevated activities are ascribed to the accident at the Fukushima Dai-ichi nuclear reactor complex in Japan that followed the 11 March earthquake and tsunami. The activity levels observed at no time presented health concerns.

  20. Treatment of HER2-Expressing Breast Cancer and Ovarian Cancer Cells With Alpha Particle-Emitting {sup 227}Th-Trastuzumab

    SciTech Connect (OSTI)

    Heyerdahl, Helen; Krogh, Cecilie; Borrebaek, Jorgen; Larsen, Asmund; Dahle, Jostein

    2011-02-01

    Purpose: To evaluate the cytotoxic effects of low-dose-rate alpha particle-emitting radioimmunoconjugate {sup 227}Th-p-isothiocyanato-benzyl-DOTA-trastuzumab ({sup 227}Th-trastuzumab [where DOTA is 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]) internalized by breast and ovarian cancer cell lines in order to assess the potential of {sup 227}Th-trastuzumab as a therapeutic agent against metastatic cancers that overexpress the HER2 oncogene. Methods and Materials: Clonogenic survival and cell growth rates of breast cancer cells treated with {sup 227}Th-trastuzumab were compared with rates of cells treated with nonbinding {sup 227}Th-rituximab, cold trastuzumab, and X-radiation. Cell growth experiments were also performed with ovarian cancer cells. Cell-associated radioactivity was measured at several time points, and the mean radiation dose to cells was calculated. Results: SKBR-3 cells got 50% of the mean absorbed radiation dose from internalized activity and 50% from cell surface-bound activity, while BT-474 and SKOV-3 cells got 75% radiation dose from internalized activity and 25% from cell surface-bound activity. Incubation of breast cancer cells with 2.5 kBq/ml {sup 227}Th-trastuzumab for 1 h at 4{sup o}C, followed by washing, resulted in mean absorbed radiation doses of 2 to 2.5 Gy. A dose-dependent inhibition of cell growth and an increase in apoptosis were induced in all cell lines. Conclusions: Clinically relevant activity concentrations of {sup 227}Th-trastuzumab induced a specific cytotoxic effect in three HER2-expressing cell lines. The cytotoxic effect of {sup 227}Th-trastuzumab was higher than that of single-dose X-radiation (relative biological effectiveness = 1.2). These results warrant further studies of treatment of breast cancer and ovarian cancer with {sup 227}Th-trastuzumab.

  1. Isolation and Puification of Uranium Isotopes for Measurement by Mass-Spectrometry (233, 234, 235, 236, 238U) and Alpha Spectrometry (232U)

    SciTech Connect (OSTI)

    Marinelli, R; Hamilton, T; Brown, T; Marchetti, A; Williams, R; Tumey, S

    2006-05-30

    This report describes a standardized methodology used by researchers from the Center for Accelerator Mass Spectrometry (CAMS) (Energy and Environment Directorate) and the Environmental Radiochemistry Group (Chemistry and Materials Science Directorate) at the Lawrence Livermore National Laboratory (LLNL) for the full isotopic analysis of uranium from solution. The methodology has largely been developed for use in characterizing the uranium composition of selected nuclear materials but may also be applicable to environmental studies and assessments of public, military or occupational exposures to uranium using in-vitro bioassay monitoring techniques. Uranium isotope concentrations and isotopic ratios are measured using a combination of Multi Collector Inductively Coupled Plasma Mass Spectrometry (MC ICP-MS), Accelerator Mass Spectrometry (AMS) and Alpha Spectrometry.

  2. Alpha Backgrounds for HPGe Detectors in Neutrinoless Double-Beta Decay Experiments

    E-Print Network [OSTI]

    R. A. Johnson; T. H. Burritt; S. R. Elliott; V. M. Gehman; V. E. Guiseppe; J. F. Wilkerson

    2011-12-30

    The Majorana Experiment will use arrays of enriched HPGe detectors to search for the neutrinoless double-beta decay of 76Ge. Such a decay, if found, would show lepton-number violation and confirm the Majorana nature of the neutrino. Searches for such rare events are hindered by obscuring backgrounds which must be understood and mitigated as much as possible. A potentially important background contribution to this and other double-beta decay experiments could come from decays of alpha-emitting isotopes in the 232Th and 238U decay chains on or near the surfaces of the detectors. An alpha particle emitted external to an HPGe crystal can lose energy before entering the active region of the detector, either in some external-bulk material or within the dead region of the crystal. The measured energy of the event will only correspond to a partial amount of the total kinetic energy of the alpha and might obscure the signal from neutrinoless double-beta decay. A test stand was built and measurements were performed to quantitatively assess this background. We present results from these measurements and compare them to simulations using Geant4. These results are then used to measure the alpha backgrounds in an underground detector in situ. We also make estimates of surface contamination tolerances for double-beta decay experiments using solid-state detectors.

  3. Alpha Backgrounds for HPGe Detectors in Neutrinoless Double-Beta Decay Experiments

    SciTech Connect (OSTI)

    Johnson, R. A. [University of Washington, Seattle; Burritt, T. H. [University of Washington, Seattle; Elliott, S. R. [Los Alamos National Laboratory (LANL); Gehman, V. M. [Los Alamos National Laboratory (LANL); Guiseppe, V.E. [University of South Dakota; Wilkerson, J. F. [UNC/Triangle Univ. Nucl. Lab, Durham, NC/ORNL

    2012-01-01

    The Majorana Experiment will use arrays of enriched HPGe detectors to search for the neutrinoless double-beta decay of 76Ge. Such a decay, if found, would show lepton-number violation and confirm the Majorana nature of the neutrino. Searches for such rare events are hindered by obscuring backgrounds which must be understood and mitigated as much as possible. A potentially important background contribution to this and other double-beta decay experiments could come from decays of alpha-emitting isotopes in the 232Th and 238U decay chains on or near the surfaces of the detectors. An alpha particle emitted external to an HPGe crystal can lose energy before entering the active region of the detector, either in some external-bulk material or within the dead region of the crystal. The measured energy of the event will only correspond to a partial amount of the total kinetic energy of the alpha and might obscure the signal from neutrinoless double-beta decay. A test stand was built and measurements were performed to quantitatively assess this background. We present results from these measurements and compare them to simulations using Geant4. These results are then used to measure the alpha backgrounds in an underground detector in situ. We also make estimates of surface contamination tolerances for double-beta decay experiments using solid-state detectors.

  4. Laser isotope purification of lead for use in semiconductor chip interconnects

    SciTech Connect (OSTI)

    Scheibner, K.; Haynam, C.; Worden, E.; Esser, B.

    1996-03-19

    Lead, used throughout the electronics industries, typically contains small amounts of radioactive {sup 210}Pb (a daughter product of the planets ubiquitous {sup 238}U) whose {sup 210}Po daughter emits an {alpha}-particle that is known to cause soft errors in electronic circuits. The {sup 210}Pb is not separable by chemical means. This paper describes the generic Atomic Vapor Laser Isotope Separation (AVLIS) process developed at the Lawrence Livermore National Laboratory (LLNL) over the last 20 years, with particular emphasis on recent efforts to develop the process physics and component technologies required to remove the offending {sup 210}Pb using lasers. We have constructed a developmental facility that includes a process laser development area and a test bed for the vaporizer and ion and product collectors. We will be testing much of the equipment and demonstrating pilot scale AVLIS on a surrogate material later this year. Detection of the very low alpha emission even from commercially available low-alpha lead is challenging. LLNL`s detection capabilities will be described. The goal of the development of lead purification technology is to demonstrate the capability in FY97, and to deploy a production machine capable of up to several MT/y of isotopically purified material, possible beginning in FY98.

  5. Laser isotope purification of lead for use in semiconductor chip interconnects

    SciTech Connect (OSTI)

    Scheibner, K.; Haynam, C.; Worden, E.; Esser, B.

    1996-02-01

    Lead, used throughout the electronics industries, typically contains small amounts of radioactive {sup 210}Pb (a daughter product of the planet`s ubiquitous {sup 210}U) whose {sup 210}Po daughter emits and {alpha}-particle that is known to cause soft errors in electronic circuits. The {sup 210}Pb is not easily separable by chemical means. This paper describes the generic Atomic Vapor Laser Isotope Separation (AVLIS) process developed at the Lawrence Livermore National Laboratory (LLNL) over the last 20 years, with particular emphasis on recent efforts to develop the process physics and component technologies required to remove the offending {sup 210}Pb using lasers. We have constructed a developmental facility that includes a process laser development area and a test bed for the vaporizer and ion and product collectors. We will be testing much of the equipment and demonstrating pilot-scale AVLIS on a surrogate material later this year. Detection of the very low alpha emission even from commercially available low-alpha lead is challenging. LLNL`s detection capabilities will be described. The goal of the development of lead purification technology is to demonstrate the capability in FY97, and to begin filling orders of up to several MT/y of isotopically purified material in FY98.

  6. Light emitting ceramic device

    DOE Patents [OSTI]

    Valentine, Paul; Edwards, Doreen D.; Walker, Jr., William John; Slack, Lyle H.; Brown, Wayne Douglas; Osborne, Cathy; Norton, Michael; Begley, Richard

    2010-05-18

    A light-emitting ceramic based panel, hereafter termed "electroceramescent" panel, is herein claimed. The electroceramescent panel is formed on a substrate providing mechanical support as well as serving as the base electrode for the device. One or more semiconductive ceramic layers directly overlay the substrate, and electrical conductivity and ionic diffusion are controlled. Light emitting regions overlay the semiconductive ceramic layers, and said regions consist sequentially of a layer of a ceramic insulation layer and an electroluminescent layer, comprised of doped phosphors or the equivalent. One or more conductive top electrode layers having optically transmissive areas overlay the light emitting regions, and a multi-layered top barrier cover comprising one or more optically transmissive non-combustible insulation layers overlay said top electrode regions.

  7. Methods for the synthesis and polymerization of .alpha.,.alpha.'-dihalo-p-xylenes

    DOE Patents [OSTI]

    Ferraris, John P. (Coppell, TX); Neef, Charles J. (Garland, TX)

    2002-07-30

    The present invention describes an improved method for the polymerization of .alpha.,.alpha.-dihalo-p-xylene's such as the .alpha.,.alpha.'-dihalo-2-methoxy-5-(2-ethylhexyloxy)-xylene's. The procedure for synthesis is based on the specific order of addition of reagents and the use of an anionic initiator that allows control of the molecular weight of the polymer. The molecular weight control allows processability of the polymer which is important for its utility in applications including in light-emitting-diodes, field effect transistors and photovoltaic devices.

  8. Transport of Radioactive Material by Alpha Recoil

    SciTech Connect (OSTI)

    Icenhour, A.S.

    2005-05-19

    The movement of high-specific-activity radioactive particles (i.e., alpha recoil) has been observed and studied since the early 1900s. These studies have been motivated by concerns about containment of radioactivity and the protection of human health. Additionally, studies have investigated the potential advantage of alpha recoil to effect separations of various isotopes. This report provides a review of the observations and results of a number of the studies.

  9. Use of MCNPX for Alpha Spectrometry Simulations of a Continuous Air Monitor

    SciTech Connect (OSTI)

    Robert Hayes, Craig Marianno

    2007-01-01

    The purpose of this study was to determine if the alpha energy spectrum in a Passive Implanted Planar Silicon (PIPS) detector, as modeled by MCNPX [1], can be used to design a radon stripping algorithm for a continuous air monitor (CAM). This stripping algorithm would be employed to discriminate naturally occurring radioisotopes from the anthropogenic for nuclear safety -related applications. It is hoped that using an algorithm based on MCNPX simulations, the CAM will not be prone to false alarms when radon levels are dynamic as identified in other CAM systems [2,3]. This work is focused on the design of the next generation air particulate detector (NGAPD) for the United States Navy. The primary isotope of interest is Co-60. This radionuclide emits a beta with an average energy of 96 keV. Therefore, once deposited on the CAM filter, it will produce a beta continuum seen by the PIPS detector. In addition, as radon progeny is deposited on the air filter, these will give rise to characteristic alpha peaks and a beta continuum. This is primarily an issue in port-or land-based applications. Ultimately, measurement of a radon alpha spectrum is desired to predict the amount of beta activity which would be measured from the radon progeny decay chains. All excess beta activity could then be attributed to anthropogenic sources once the radon progeny contributions have been stripped out.

  10. Scintillation of thin tetraphenyl butadiene films under alpha particle excitation

    E-Print Network [OSTI]

    Pollmann, Tina; Ku?niak, Marcin

    2010-01-01

    The alpha induced scintillation of the wavelength shifter 1,1,4,4-tetraphenyl-1,3-butadiene (TPB) was studied to improve the understanding of possible surface alpha backgrounds in the DEAP dark matter search experiment. We found that vacuum deposited thin TPB films emit 882 +/-210 photons per MeV under alpha particle excitation. The scintillation pulse shape consists of a double exponential decay with lifetimes of 11 +/-5 ns and 275 +/-10ns.

  11. AVLIS enrichment of medical isotopes

    SciTech Connect (OSTI)

    Haynam, C.A.; Scheibner, K.F.; Stern, R.C.; Worden, E.F.

    1996-12-31

    Under the Sponsorship of the United states Enrichment Corporation (USEC), we are currently investigating the large scale separation of several isotopes of medical interest using atomic vapor isotope separation (AVLIS). This work includes analysis and experiments in the enrichment of thallium 203 as a precursor to the production of thallium 201 used in cardiac imaging following heart attacks, on the stripping of strontium 84 from natural strontium as precursor to the production of strontium 89, and on the stripping of lead 210 from lead used in integrated circuits to reduce the number of alpha particle induced logic errors.

  12. Alpha Radiation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O D S TA I N P A T TSorbentsAllosteric ModulationAlphaBasics

  13. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1993-01-01

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

  14. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1993-03-30

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

  15. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1991-05-08

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using, a metal hydride.

  16. Toward ZnO Light Emitting Diode

    E-Print Network [OSTI]

    Liu, Jianlin

    2008-01-01

    applications such as light emitting diodes (LEDs) and laser009 "Toward ZnO Light Emitting Diode" Jianlin Liu July 2008Title: “Toward ZnO Light Emitting Diode” Sponsor: UC Energy

  17. SciTech Connect: "light emitting diode"

    Office of Scientific and Technical Information (OSTI)

    light emitting diode" Find + Advanced Search Term Search Semantic Search Advanced Search All Fields: "light emitting diode" Semantic Semantic Term Title: Full Text:...

  18. Ab initio alpha-alpha scattering

    E-Print Network [OSTI]

    Serdar Elhatisari; Dean Lee; Gautam Rupak; Evgeny Epelbaum; Hermann Krebs; Timo A. Lähde; Thomas Luu; Ulf-G. Meißner

    2015-06-11

    Processes involving alpha particles and alpha-like nuclei comprise a major part of stellar nucleosynthesis and hypothesized mechanisms for thermonuclear supernovae. In an effort towards understanding alpha processes from first principles, we describe in this letter the first ab initio calculation of alpha-alpha scattering. We use lattice effective field theory to describe the low-energy interactions of nucleons and apply a technique called the adiabatic projection method to reduce the eight-body system to an effective two-cluster system. We find good agreement between lattice results and experimental phase shifts for S-wave and D-wave scattering. The computational scaling with particle number suggests that alpha processes involving heavier nuclei are also within reach in the near future.

  19. Ab initio alpha-alpha scattering

    E-Print Network [OSTI]

    Elhatisari, Serdar; Rupak, Gautam; Epelbaum, Evgeny; Krebs, Hermann; Lähde, Timo A; Luu, Thomas; Meißner, Ulf-G

    2015-01-01

    Processes involving alpha particles and alpha-like nuclei comprise a major part of stellar nucleosynthesis and hypothesized mechanisms for thermonuclear supernovae. In an effort towards understanding alpha processes from first principles, we describe in this letter the first ab initio calculation of alpha-alpha scattering. We use lattice effective field theory to describe the low-energy interactions of nucleons and apply a technique called the adiabatic projection method to reduce the eight-body system to an effective two-cluster system. We find good agreement between lattice results and experimental phase shifts for S-wave and D-wave scattering. The computational scaling with particle number suggests that alpha processes involving heavier nuclei are also within reach in the near future.

  20. Blue light emitting thiogallate phosphor

    DOE Patents [OSTI]

    Dye, Robert C. (Los Alamos, NM); Smith, David C. (Los Alamos, NM); King, Christopher N. (Portland, OR); Tuenge, Richard T. (Hillsboro, OR)

    1998-01-01

    A crystalline blue emitting thiogallate phosphor of the formula RGa.sub.2 S.sub.4 :Ce.sub.x where R is selected from the group consisting of calcium, strontium, barium and zinc, and x is from about 1 to 10 atomic percent, the phosphor characterized as having a crystalline microstructure on the size order of from about 100 .ANG. to about 10,000 .ANG. is provided together with a process of preparing a crystalline blue emitting thiogallate phosphor by depositing on a substrate by CVD and resultant thin film electroluminescent devices including a layer of such deposited phosphor on an ordinary glass substrate.

  1. Production of A=6,7 Nuclides in the Alpha + Alpha Reaction and Cosmic Ray Nucleosynthesis

    E-Print Network [OSTI]

    David J. Mercer; Sam M. Austin; J. A. Brown; S. A. Danczyk; S. E. Hirzebruck; J. H. Kelley; T. Suomijarvi; D. A. Roberts; T. P Walker

    2001-04-03

    Cross sections for production of 6He, 6Li, 7Li, and 7Be in the alpha+alpha reaction were measured at bombarding energies of 159.3, 279.6, and 619.8 MeV, and are found to decrease rapidly with increasing energy. These cross sections are essential for the calculation of the rate of nucleosynthesis of the lithium isotopes in the cosmic rays and thereby play a key role in our understanding of the synthesis of Li, Be, and B. The results for 6Li differ significantly from the tabulated values commonly used in cosmic-ray production calculations and lead to lower production of 6Li.

  2. High-efficiency microcavity top-emitting organic light-emitting diodes using silver anode

    E-Print Network [OSTI]

    -film transistors can be bur- ied under the organic light-emitting diode OLED .3 Thus, complicated pixel circuitsHigh-efficiency microcavity top-emitting organic light-emitting diodes using silver anode Huajun February 2006 Top-emitting organic light-emitting diodes TOLEDs employing highly reflective Ag as anode

  3. Introduction In nuclear medicine, a pharmaceutical tagged with a radioactive isotope (a radio

    E-Print Network [OSTI]

    Duncan, James S.

    tomographic imaging methods in medicine. The first medical scanner to perform x­ray computed tomography (x the gamma rays emitted in the radioactive decay of the isotope. Unlike x­ray techniques, where the radiation within the lungs is mapped by detecting the gamma rays emitted. A conventional nuclear medicine image

  4. Broadband light-emitting diode

    DOE Patents [OSTI]

    Fritz, I.J.; Klem, J.F.; Hafich, M.J.

    1998-07-14

    A broadband light-emitting diode is disclosed. The broadband light-emitting diode (LED) comprises a plurality of III-V compound semiconductor layers grown on a semiconductor substrate, with the semiconductor layers including a pair of cladding layers sandwiched about a strained-quantum-well active region having a plurality of different energy bandgaps for generating light in a wavelength range of about 1.3--2 {micro}m. In one embodiment of the present invention, the active region may comprise a first-grown quantum-well layer and a last-grown quantum-well layer that are oppositely strained; whereas in another embodiment of the invention, the active region is formed from a short-period superlattice structure (i.e. a pseudo alloy) comprising alternating thin layers of InGaAs and InGaAlAs. The use a short-period superlattice structure for the active region allows different layers within the active region to be simply and accurately grown by repetitively opening and closing one or more shutters in an MBE growth apparatus to repetitively switch between different growth states therein. The broadband LED may be formed as either a surface-emitting LED or as an edge-emitting LED for use in applications such as chemical sensing, fiber optic gyroscopes, wavelength-divisionmultiplexed (WDM) fiber-optic data links, and WDM fiber-optic sensor networks for automobiles and aircraft. 10 figs.

  5. Broadband light-emitting diode

    DOE Patents [OSTI]

    Fritz, Ian J. (Albuquerque, NM); Klem, John F. (Sandia Park, NM); Hafich, Michael J. (Albuquerque, NM)

    1998-01-01

    A broadband light-emitting diode. The broadband light-emitting diode (LED) comprises a plurality of III-V compound semiconductor layers grown on a semiconductor substrate, with the semiconductor layers including a pair of cladding layers sandwiched about a strained-quantum-well active region having a plurality of different energy bandgaps for generating light in a wavelength range of about 1.3-2 .mu.m. In one embodiment of the present invention, the active region may comprise a first-grown quantum-well layer and a last-grown quantum-well layer that are oppositely strained; whereas in another embodiment of the invention, the active region is formed from a short-period superlattice structure (i.e. a pseudo alloy) comprising alternating thin layers of InGaAs and InGaAlAs. The use a short-period superlattice structure for the active region allows different layers within the active region to be simply and accurately grown by repetitively opening and closing one or more shutters in an MBE growth apparatus to repetitively switch between different growth states therein. The broadband LED may be formed as either a surface-emitting LED or as an edge-emitting LED for use in applications such as chemical sensing, fiber optic gyroscopes, wavelength-division-multiplexed (WDM) fiber-optic data links, and WDM fiber-optic sensor networks for automobiles and aircraft.

  6. PPPL-2878 UC-426 February 1993 Tritium Diagnostics by Balmer-alpha Emission

    E-Print Network [OSTI]

    PPPL-2878 UC-426 February 1993 Tritium Diagnostics by Balmer-alpha Emission C H Skinner, A T Ramsey emission from tritium in a plasma may be distinguished from deuterium emission by a small isotope shift. A diagnostic system to measure tritium Balmer-alpha emission from the plasma edge has been installed on TFTR

  7. Isotopes Products

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATIONIntroducing theActivation byIs a SmallIsotope

  8. Investigating Heavy Metal Contamination of the Puget Sound Environment with New Isotopic Tracers Rachel Weber, Senior, Earth and Space Sciences, Mary Gates Scholar

    E-Print Network [OSTI]

    Winglee, Robert M.

    Sciences Tacoma Smelter Background The Tacoma Smelter operated for approximately 100 years at the southern to calibrate isotopic tracers of heavy metals emitted by the Tacoma Smelter. Preliminary data from lead isotope a clear isotopic fingerprint of Tacoma Smelter Pb. The analytical error is smaller than the data points

  9. Quantum Dot Light Emitting Diode

    SciTech Connect (OSTI)

    Keith Kahen

    2008-07-31

    The project objective is to create low cost coatable inorganic light emitting diodes, composed of quantum dot emitters and inorganic nanoparticles, which have the potential for efficiencies equivalent to that of LEDs and OLEDs and lifetime, brightness, and environmental stability between that of LEDs and OLEDs. At the end of the project the Recipient shall gain an understanding of the device physics and properties of Quantum-Dot LEDs (QD-LEDs), have reliable and accurate nanocrystal synthesis routines, and have formed green-yellow emitting QD-LEDs with a device efficiency greater than 3 lumens/W, a brightness greater than 400 cd/m2, and a device operational lifetime of more than 1000 hours. Thus the aim of the project is to break the current cost-efficiency paradigm by creating novel low cost inorganic LEDs composed of inorganic nanoparticles.

  10. Quantum Dot Light Emitting Diode

    SciTech Connect (OSTI)

    Kahen, Keith

    2008-07-31

    The project objective is to create low cost coatable inorganic light emitting diodes, composed of quantum dot emitters and inorganic nanoparticles, which have the potential for efficiencies equivalent to that of LEDs and OLEDs and lifetime, brightness, and environmental stability between that of LEDs and OLEDs. At the end of the project the Recipient shall gain an understanding of the device physics and properties of Quantum-Dot LEDs (QD-LEDs), have reliable and accurate nanocrystal synthesis routines, and have formed green-yellow emitting QD-LEDs with a device efficiency greater than 3 lumens/W, a brightness greater than 400 cd/m{sup 2}, and a device operational lifetime of more than 1000 hours. Thus the aim of the project is to break the current cost-efficiency paradigm by creating novel low cost inorganic LEDs composed of inorganic nanoparticles.

  11. Porous light-emitting compositions

    DOE Patents [OSTI]

    Burrell, Anthony K. (Los Alamos, NM); McCleskey, Thomas Mark (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Bauer, Eve (Los Alamos, NM); Mueller, Alexander H. (Los Alamos, NM)

    2012-04-17

    Light-emitting devices are prepared by coating a porous substrate using a polymer-assisted deposition process. Solutions of metal precursor and soluble polymers having binding properties for metal precursor were coated onto porous substrates. The coated substrates were heated at high temperatures under a suitable atmosphere. The result was a substrate with a conformal coating that did not substantially block the pores of the substrate.

  12. LIGHT EMITTING DIODE CHARACTERISTICS (SAMPLE LAB WRITEUP)

    E-Print Network [OSTI]

    McNeill, John A.

    1 LIGHT EMITTING DIODE CHARACTERISTICS (SAMPLE LAB WRITEUP) John A. McNeill ECE Box 000 January 19, 1997 ABSTRACT This lab investigates the V-I characteristic of a light-emitting diode (LED

  13. Electrodeposited Light-Emitting Nanojunctions Wendong Xing,

    E-Print Network [OSTI]

    Potma, Eric Olaf

    Electrodeposited Light-Emitting Nanojunctions Wendong Xing, Wenbo Yan, Talin Ayvazian, Yong Wang-CdSe. Light-emitting nanojunctions (LEnJs) prepared at both temperatures show a low threshold voltage for light emission of

  14. White light-emitting organic electroluminescent devices

    DOE Patents [OSTI]

    Shiang, Joseph John; Duggal, Anil Raj; Parthasarathy, Gautam

    2006-06-20

    A light-emitting device comprises a light-emitting member, which comprises two electrodes, at least two organic electroluminescent ("EL") materials disposed between the electrodes, a charge blocking material disposed between the electrodes, and at least one photoluminescent ("PL") material. The light-emitting member emits electromagnetic ("EM") radiation having a first spectrum in response to a voltage applied across the two electrodes. The PL material absorbs a portion of the EM radiation emitted by the light-emitting member and emits EM radiation having second spectrum different than the first spectrum. Each of the organic EL materials emits EM radiation having a wavelength range selected from the group consisting of blue and red wavelength ranges.

  15. Isotopic Anomalies in CP Stars: Helium, Mercury, Platinum, and Calcium

    E-Print Network [OSTI]

    C. R. Cowley; S. Hubrig; F. Castelli

    2007-11-15

    We review the classical observational results for isotopic abundance variations for several elements in CP stars. We concentrate on the "newest" anomaly, in calcium. The cosmically very rare isotope, Ca-48 can rival and even dominate the more common, alpha nuclide, Ca-40. Relevant examples are found in the hot, non-magnetic HgMn stars, and the field horizontal-branch star, Feige 86. The calcium anomaly is also present in cool, magnetic stars, including the notorious HD 101065, Przybylski's star.

  16. Visible light emitting vertical cavity surface emitting lasers

    DOE Patents [OSTI]

    Bryan, R.P.; Olbright, G.R.; Lott, J.A.; Schneider, R.P. Jr.

    1995-06-27

    A vertical cavity surface emitting laser that emits visible radiation is built upon a substrate, then having mirrors, the first mirror on top of the substrate; both sets of mirrors being a distributed Bragg reflector of either dielectrics or other materials which affect the resistivity or of semiconductors, such that the structure within the mirror comprises a plurality of sets, each having a thickness of {lambda}/2n where n is the index of refraction of each of the sets; each of the mirrors adjacent to spacers which are on either side of an optically active bulk or quantum well layer; and the spacers and the optically active layer are from one of the following material systems: In{sub z}(Al{sub y}Ga{sub 1{minus}y}){sub 1{minus}z}P, InAlGaAs, AlGaAs, InGaAs, or AlGaP/GaP, wherein the optically active region having a length equal to m {lambda}/2n{sub eff} where m is an integer and n{sub eff} is the effective index of refraction of the laser cavity, and the spacer layer and one of the mirrors being transmissive to radiation having a wavelength of {lambda}/n, typically within the green to red portion of the visible spectrum. 10 figs.

  17. Measurement of the Internal Magnetic Field of Plasmas using an Alpha Particle Source

    SciTech Connect (OSTI)

    S.J. Zweben; D.S. Darrow; P.W. Ross; J.L. Lowrance; G. Renda

    2004-05-13

    The internal magnetic fields of plasmas can be measured under certain conditions from the integrated v x B deflection of MeV alpha particles emitted by a small radioactive source. This alpha source and large-area alpha particle detector would be located inside the vacuum vessel but outside the plasma. Alphas with a typical energy of 5.5 MeV (241Am) can reach the center of almost all laboratory plasmas and magnetic fusion devices, so this method can potentially determine the q(r) profile of tokamaks or STs. Orbit calculations, background evaluations, and conceptual designs for such a vxB (or ''AVB'') detector are described.

  18. Event counting alpha detector

    DOE Patents [OSTI]

    Bolton, R.D.; MacArthur, D.W.

    1996-08-27

    An electrostatic detector is disclosed for atmospheric radon or other weak sources of alpha radiation. In one embodiment, nested enclosures are insulated from one another, open at the top, and have a high voltage pin inside and insulated from the inside enclosure. An electric field is produced between the pin and the inside enclosure. Air ions produced by collision with alpha particles inside the decay volume defined by the inside enclosure are attracted to the pin and the inner enclosure. With low alpha concentrations, individual alpha events can be measured to indicate the presence of radon or other alpha radiation. In another embodiment, an electrical field is produced between parallel plates which are insulated from a single decay cavity enclosure. 6 figs.

  19. Event counting alpha detector

    DOE Patents [OSTI]

    Bolton, Richard D. (Los Alamos, NM); MacArthur, Duncan W. (Los Alamos, NM)

    1996-01-01

    An electrostatic detector for atmospheric radon or other weak sources of alpha radiation. In one embodiment, nested enclosures are insulated from one another, open at the top, and have a high voltage pin inside and insulated from the inside enclosure. An electric field is produced between the pin and the inside enclosure. Air ions produced by collision with alpha particles inside the decay volume defined by the inside enclosure are attracted to the pin and the inner enclosure. With low alpha concentrations, individual alpha events can be measured to indicate the presence of radon or other alpha radiation. In another embodiment, an electrical field is produced between parallel plates which are insulated from a single decay cavity enclosure.

  20. Energy Savings Estimates of Light Emitting Diodes

    Broader source: Energy.gov [DOE]

    This report is an analysis of niche markets and applications for light emitting diodes (LEDs), undertaken on behalf of the U.S. Department of Energy

  1. Examining the stability of thermally fissile Th and U isotopes

    E-Print Network [OSTI]

    Bharat Kumar; S. K. Biswal; S. K. Singh; S. K. Patra

    2015-08-03

    The properties of recently predicted thermally fissile Th and U isotopes are studied within the framework of relativistic mean field (RMF) approach using axially deformed basis. We calculated the ground, first intrinsic excited state and matter density for highly neutron-rich thorium and uranium isotopes. The possible modes of decay like $\\alpha$-decay and $\\beta$-decay are analyzed. We found that the neutron-rich isotopes are stable against $\\alpha$-decay, however they are very much unstable against $\\beta$-decay. The life time of these nuclei predicted to be tens of second against $\\beta$-decay. If these nuclei utilize before their decay time, a lots of energy can be produced within the help of multi-fragmentation fission. Also, these nuclei have a great implication in astrophysical point of view. The total nucleonic densities distribution are calculated, from which the clusters inside the parent nuclei are determined. %Most of the thorium isotopes are $\\alpha$ emitters, where as some %of them have short half-lives. In some cases, we found the isomeric states with energy range from 2 to 3 MeV and three minima in the potential energy surface of $^{228-230}$Th and $^{228-234}$U isotopes.

  2. {alpha} decay of {sup 180,181}Pb

    SciTech Connect (OSTI)

    Andreyev, A. N.; Antalic, S.; Saro, S.; Ackermann, D.; Comas, V. F.; Heinz, S.; Heredia, J. A.; Hessberger, F. P.; Khuyagbaatar, J.; Kojouharov, I.; Kindler, B.; Lommel, B.; Mann, R.; Cocolios, T. E.; Elseviers, J.; Huyse, M.; Duppen, P. Van; Venhart, M.; Franchoo, S.; Hofmann, S.

    2009-11-15

    A detailed {alpha}-decay study of the neutron-deficient isotope {sup 181}Pb has been performed in the complete fusion reaction {sup 40}Ca+{sup 144}Sm{yields}{sup 184}Pb* at the velocity filter SHIP (GSI, Darmstadt). In comparison with the literature, more precise data have been deduced for the I{sup {pi}}=(9/2{sup -}) ground state in this nucleus, which is presumably based on the neutron {nu}h{sub 9/2} spherical orbital. Improved {alpha}-decay data were also measured for {sup 180}Pb.

  3. Evaluation of beta partical densitometry for determination of self-absorption factors in gross alpha and gross beta radioactivity measurements on air particulate filter samples 

    E-Print Network [OSTI]

    Breida, Margaret A

    1994-01-01

    Alpha and beta particles emitted from radioactive material collected on an air filter may be significantly attenuated by the mass (thickness) of collected dust. In this study, we determined the mass or thickness of the simulated dust deposit...

  4. Modeling of temporal behavior of isotopic exchange between gaseous hydrogen and palladium hydride power

    SciTech Connect (OSTI)

    Melius, C F; Foltz, G W

    1987-01-01

    A parametric rate-equation model is described which depicts the time dependent behavior of the isotopic exchange process occurring between the solid and gas phases in gaseous hydrogen (deuterium) flows through packed-powder palladium deuteride (hydride) beds. The exchange mechanism is assumed to be rate-limited by processes taking place on the surface of the powder. The fundamental kinetic parameter of the model is the isotopic exchange probability, p, which is the probability that an isotopic exchange event occurs during a collision of a gas phase atom with the surface. Isotope effects between the gas and solid phases are explicitly included in terms of the isotope separation factor, ..cap alpha... Results of the model are compared with recent experimental measurements of isotope exchange in the ..beta..-phase hydrogen/palladium system and, using a literature value of ..cap alpha.. = 2.4, a good description of the experimental data is obtained for p approx. 10/sup -7/. In view of the importance of the isotope effects in the hydrogen/palladium system and the range of ..cap alpha.. values reported for the ..beta..-phase in the literature, the sensitivity of the model results to a variation in the value of ..cap alpha.. is examined.

  5. Alpha Particle Diagnostic

    SciTech Connect (OSTI)

    Fisher, Ray, K.

    2009-05-13

    The study of burning plasmas is the next frontier in fusion energy research, and will be a major objective of the U.S. fusion program through U.S. collaboration with our international partners on the ITER Project. For DT magnetic fusion to be useful for energy production, it is essential that the energetic alpha particles produced by the fusion reactions be confined long enough to deposit a significant fraction of their initial ~3.5 MeV energy in the plasma before they are lost. Development of diagnostics to study the behavior of energetic confined alpha particles is a very important if not essential part of burning plasma research. Despite the clear need for these measurements, development of diagnostics to study confined the fast confined alphas to date has proven extremely difficult, and the available techniques remain for the most part unproven and with significant uncertainties. Research under this grant had the goal of developing diagnostics of fast confined alphas, primarily based on measurements of the neutron and ion tails resulting from alpha particle knock-on collisions with the plasma deuterium and tritium fuel ions. One of the strengths of this approach is the ability to measure the alphas in the hot plasma core where the interesting ignition physics will occur.

  6. Green emitting phosphors and blends thereof

    DOE Patents [OSTI]

    Setlur, Anant Achyut (Niskayuna, NY); Siclovan, Oltea Puica (Rexford, NY); Nammalwar, Prasanth Kumar (Bangalore, IN); Sathyanarayan, Ramesh Rao (Bangalore, IN); Porob, Digamber G. (Goa, IN); Chandran, Ramachandran Gopi (Bangalore, IN); Heward, William Jordan (Saratoga Springs, NY); Radkov, Emil Vergilov (Euclid, OH); Briel, Linda Jane Valyou (Niskayuna, NY)

    2010-12-28

    Phosphor compositions, blends thereof and light emitting devices including white light emitting LED based devices, and backlights, based on such phosphor compositions. The devices include a light source and a phosphor material as described. Also disclosed are phosphor blends including such a phosphor and devices made therefrom.

  7. Light emitting device having peripheral emissive region

    DOE Patents [OSTI]

    Forrest, Stephen R

    2013-05-28

    Light emitting devices are provided that include one or more OLEDs disposed only on a peripheral region of the substrate. An OLED may be disposed only on a peripheral region of a substantially transparent substrate and configured to emit light into the substrate. Another surface of the substrate may be roughened or include other features to outcouple light from the substrate. The edges of the substrate may be beveled and/or reflective. The area of the OLED(s) may be relatively small compared to the substrate surface area through which light is emitted from the device. One or more OLEDs also or alternatively may be disposed on an edge of the substrate about perpendicular to the surface of the substrate through which light is emitted, such that they emit light into the substrate. A mode expanding region may be included between each such OLED and the substrate.

  8. Studies of isotopic exchange between gaseous hydrogen and palladium hydride powder

    SciTech Connect (OSTI)

    Foltz, G.W.; Melius, C.F.

    1987-12-01

    A gas flow apparatus has been constructed and used to study the isotopic exchange reaction occurring between the solid and gas phases in hydrogen (deuterium) gas flows directed through packed-powder beds of ..beta..-phase palladium deuteride (hydride). Spontaneous Raman light scattering is employed to obtain a real-time analysis of the isotopic composition of the gas (H/sub 2/, D/sub 2/, HD) exiting from the bed. A parametric rate-equation model is described which depicts the time-dependent behavior of the isotopic exchange process. The exchange mechanism is assumed to be rate-limited by processes occurring on the surface of the powder. The fundamental kinetic parameter of the model is the isotopic exchange probability, p, which is the probability that an isotopic exchange event occurs during a collision of a gas-phase atom with the surface. Isotope effects between the gas and solid phases are explicitly included in terms of the isotope separation factor, ..cap alpha... Results of the model are compared with the experimental measurements and, using a literature value of ..cap alpha.. = 2.4, good agreement is obtained for p approx. = 10/sup -7/. In view of the importance of the isotope effects in the hydrogen/palladium system and the range of a values reported for the ..beta..-phase in the literature, the sensitivity of the model results to a variation in the value of ..cap alpha.. is examined.

  9. Elastic {alpha} scattering on {sup 112}Sn and {sup 124}Sn at astrophysically relevant energies

    SciTech Connect (OSTI)

    Galaviz, D.; Mohr, P.; Zilges, A. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt (Germany); Fueloep, Zs.; Gyuerky, Gy.; Mate, Z.; Somorjai, E. [ATOMKI, P.O. Box 51, H-4001 Debrecen (Hungary); Rauscher, T. [Departement fuer Physik und Astronomie, Universitaet Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)

    2005-06-01

    The cross sections for the elastic scattering reactions {sup 112,124}Sn({alpha},{alpha}){sup 112,124}Sn at energies above and below the Coulomb barrier are presented and compared to predictions for global {alpha}-nucleus potentials. The high precision of the new data allows a study of the global {alpha}-nucleus potentials at both the proton- and neutron-rich sides of an isotopic chain. In addition, local {alpha}-nucleus potentials have been extracted for both nuclei and used to reproduce elastic scattering data at higher energies. Predictions from the capture cross section of the reaction {sup 112}Sn({alpha},{gamma}){sup 116}Te at astrophysically relevant energies are presented and compared to experimental data.

  10. Synthesis and characterization of lanthanum phosphate nanoparticles as carriers for 223Ra and 225Ra for targeted alpha therapy

    SciTech Connect (OSTI)

    Rojas Marin, Jessika V; Woodward, Jonathan; Chen, Nan; Rondinone, Adam Justin; Castano, Carlos H; Mirzadeh, Saed

    2015-01-01

    Introduction. Targeted alpha therapy (TAT) has the potential for killing specific tumor cells with minimum collateral damage to surrounding healthy tissue. Radionuclides such as 223Ra, 225Ra, and 225Ac are of special interest for radiotherapeutic applications as they emit multiple -particles during their decay. Utilizing appropriate carriers capable of retaining both the parent radioisotope as well as daughter products is important for the effective delivery of the radioisotope to the tumor site while mitigating global in vivo radiotoxicity. Methods. In this work, core and core+2 shells (NPs with 2 additional layers of cold LaPO4 deposited on the core surfaces) LaPO4 nanoparticles (NPs) were synthesized containing either 223Ra or 225Ra/225Ac and the retention of the parents and daughters within the NPs in vitro was investigated. Results. The NPs crystallized in rhabdophane phase with mean diameters of 3.4 and 6.3 nm for core and core+2 shells, respectively. The core LaPO 4 NPs retained up to 88% of 223Ra over 35 days. However, in the core+2 shell NPs, the retention of 223Ra and its daughter, 211Pb, was improved to > 99.9% over 27 days. Additionally, the retention of 225Ra/225Ac parents was > 99.98% and ~80% for the 221Fr and 213Bi daughters over 35 days for the core+2 shell NPs. Conclusions. These results suggest that LaPO4 NPs are potentially effective carriers of radium isotopes.

  11. Fragment Isotope Distributions and the Isospin Dependent Equation of State

    E-Print Network [OSTI]

    W. P. Tan; B-A. Li; R. Donangelo; C. K. Gelbke; M-J. van Goetherm; X. D. Liu; W. G. Lynch; S. Souza; M. B. Tsang; G. Verde; A. Wagner; N. S. Xu

    2001-04-21

    Calculations predict a connection between the isotopic composition of particles emitted during an energetic nucleus-nucleus collision and the density dependence of the asymmetry term of the nuclear equation of state (EOS). This connection is investigated for central 112Sn+112Sn and 124Sn+124Sn collisions at E/A=50 MeV in the limit of an equilibrated freezeout condition. Comparisons between measured isotopic yields ratios and theoretical predictions in the equilibrium limit are used to assess the sensitivity to the density dependence of the asymmetry term of the EOS. This analysis suggests that such comparisons may provide an opportunity to constrain the asymmetry term of the EOS.

  12. Two source emission behaviour of alpha fragments of projectile having energy around 1 GeV per nucleon

    E-Print Network [OSTI]

    V. Singh; M. K. Singh; Ramji Pathak

    2010-09-17

    The emission of projectile fragments alpha has been studied in ^{84}Kr interactions with nuclei of the nuclear emulsion detector composition at relativistic energy below 2 GeV per nucleon. The angular distribution of projectile fragments alpha in terms of transverse momentum could not be explained by a straight and clean-cut collision geometry hypothesis of Participant - Spectator (PS) Model. Therefore, it is assumed that projectile fragments alpha were produced from two separate sources that belong to the projectile spectator region differing drastically in their temperatures. It has been clearly observed that the emission of projectile fragments alpha are from two different sources. The contribution of projectile fragments alpha from contact layer or hot source is a few percent of the total emission of projectile fragments alphas. Most of the projectile fragments alphas are emitted from the cold source. It has been noticed that the temperature of hot and cold regions are dependent on the projectile mass number.

  13. Two source emission behavior of projectile fragments alpha in 84^Kr interactions at around 1 GeV per nucleon

    E-Print Network [OSTI]

    M. K. Singh; Ramji Pathak; V. Singh

    2010-08-12

    The emission of projectile fragments alpha has been studied in 84^Kr interactions with nuclei of the nuclear emulsion detector composition at relativistic energy below 2 GeV per nucleon. The angular distribution of projectile fragments alpha in terms of transverse momentum could not be explained by a straight and clean-cut collision geometry hypothesis of Participant - Spectator (PS) Model. Therefore, it is assumed that projectile fragments alpha were produced from two separate sources that belong to the projectile spectator region differing drastically in their temperatures. It has been clearly observed that the emission of projectile fragments alpha are from two different sources. The contribution of projectile fragments alpha from contact layer or hot source is a few percent of the total emission of projectile fragments alphas. Most of the projectile fragments alphas are emitted from the cold source.

  14. Top-emitting Organic Light-Emitting Diode with a Cap Layer Chengfeng Qiu, Huajun Peng, Haiying Chen, Zhilang Xie,

    E-Print Network [OSTI]

    , Kowloon, Hong Kong, China ABSTRACT For top emitting Organic Light-Emitting Diodes (OLED), the study of top layer. INTRODUCTION Organic light-emitting diodes (OLEDs) [1] is challenging liquid-crystal display (LCD8.4.4-86 Top-emitting Organic Light-Emitting Diode with a Cap Layer Chengfeng Qiu, Huajun Peng

  15. Regioselective synthesis using the deuterium isotope effect

    SciTech Connect (OSTI)

    Miyano, M.

    1981-04-24

    Dehydration of 1a by various procedures invariably produced more exo olefin 2a than endo olefin 3a. This could be reversed by introduction of deuterium in the Me-21 group of the starting material. Thus, dehydration of 1b could afford more endo olefin 3b than exo olefin 2b due to the deuterium isotope effect. A regioselective synthesis of 18-oxoprogesterone (15a) from 3..beta..-hydroxypregn-5-en-20-one (5a) was carried out taking advantage of the deuterium isotope effect as depicted in Scheme I. The key steps were dehydration of 7b to predominantly endo olefin 9b and removal of the deuteriums from 18-oxoprogesterone-17..cap alpha..,21,21,21-d/sub 4/ (15b) to give 15a.

  16. Helium-cluster decay widths of molecular states in beryllium and carbon isotopes

    E-Print Network [OSTI]

    J. C. Pei; F. R. Xu

    2007-02-01

    The $\\alpha$ particle and $^6$He emissions from possible molecular states in beryllium and carbon isotopes have been studied using a mean-field-type cluster potential. Calculations can reproduce well the $\\alpha$-decay widths of excited states in $^{8}$Be, $^{12}$C and $^{20}$Ne. For the nucleus $^{10}$Be, we discussed the $\\alpha$-decay widths with different shapes or decay modes, in order to understand the very different decay widths of two excited states. The widths of $^{6}$He decay from $^{12}$Be and $\\alpha$ decays from $^{13,14}$C are predicted, which could be useful for future experiments.

  17. Examining the stability of thermally fissile Th and U isotopes

    E-Print Network [OSTI]

    Kumar, Bharat; Singh, S K; Patra, S K

    2015-01-01

    The properties of recently predicted thermally fissile Th and U isotopes are studied within the framework of relativistic mean field (RMF) approach using axially deformed basis. We calculated the ground, first intrinsic excited state and matter density for highly neutron-rich thorium and uranium isotopes. The possible modes of decay like $\\alpha$-decay and $\\beta$-decay are analyzed. We found that the neutron-rich isotopes are stable against $\\alpha$-decay, however they are very much unstable against $\\beta$-decay. The life time of these nuclei predicted to be tens of second against $\\beta$-decay. If these nuclei utilize before their decay time, a lots of energy can be produced within the help of multi-fragmentation fission. Also, these nuclei have a great implication in astrophysical point of view. The total nucleonic densities distribution are calculated, from which the clusters inside the parent nuclei are determined. %Most of the thorium isotopes are $\\alpha$ emitters, where as some %of them have short ha...

  18. Thermal pumping of light-emitting diodes

    E-Print Network [OSTI]

    Gray, Dodd (Dodd J.)

    2011-01-01

    The work presented here is a study of thermally enhanced injection in light-emitting diodes (LEDs). This effect, which we refer to as "thermal pumping", results from Peltier energy exchange from the lattice to charge ...

  19. Hybrid isotope separation scheme

    DOE Patents [OSTI]

    Maya, J.

    1991-06-18

    A method is described for yielding selectively a desired enrichment in a specific isotope including the steps of inputting into a spinning chamber a gas from which a scavenger, radiating the gas with a wave length or frequency characteristic of the absorption of a particular isotope of the atomic or molecular gas, thereby inducing a photochemical reaction between the scavenger, and collecting the specific isotope-containing chemical by using a recombination surface or by a scooping apparatus. 2 figures.

  20. Stable blue phosphorescent organic light emitting devices

    DOE Patents [OSTI]

    Forrest, Stephen R.; Thompson, Mark; Giebink, Noel

    2014-08-26

    Novel combination of materials and device architectures for organic light emitting devices is provided. An organic light emitting device, is provided, having an anode, a cathode, and an emissive layer disposed between the anode and the cathode. The emissive layer includes a host and a phosphorescent emissive dopant having a peak emissive wavelength less than 500 nm, and a radiative phosphorescent lifetime less than 1 microsecond. Preferably, the phosphorescent emissive dopant includes a ligand having a carbazole group.

  1. Stable isotope enrichment

    ScienceCinema (OSTI)

    Egle, Brian

    2014-07-15

    Brian Egle is working to increase the nation's capacity to produce stable isotopes for use including medicine, industry and national security.

  2. Stable isotope enrichment

    SciTech Connect (OSTI)

    Egle, Brian

    2014-07-14

    Brian Egle is working to increase the nation's capacity to produce stable isotopes for use including medicine, industry and national security.

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

    Energy Savers [EERE]

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

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

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

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

  5. Light-Emitting Diodes on Semipolar Bulk Gallium Nitride Substrate...

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

    Light-Emitting Diodes on Semipolar Bulk Gallium Nitride Substrate Light-Emitting Diodes on Semipolar Bulk Gallium Nitride Substrate Presenter: Arpan Chakraborty, Soraa Inc. This...

  6. SOURCES 4A: A Code for Calculating (alpha,n), Spontaneous Fission, and Delayed Neutron Sources and Spectra

    SciTech Connect (OSTI)

    Madland, D.G.; Arthur, E.D.; Estes, G.P.; Stewart, J.E.; Bozoian, M.; Perry, R.T.; Parish, T.A.; Brown, T.H.; England, T.R.; Wilson, W.B.; Charlton, W.S.

    1999-09-01

    SOURCES 4A is a computer code that determines neutron production rates and spectra from ({alpha},n) reactions, spontaneous fission, and delayed neutron emission due to the decay of radionuclides. The code is capable of calculating ({alpha},n) source rates and spectra in four types of problems: homogeneous media (i.e., a mixture of {alpha}-emitting source material and low-Z target material), two-region interface problems (i.e., a slab of {alpha}-emitting source material in contact with a slab of low-Z target material), three-region interface problems (i.e., a thin slab of low-Z target material sandwiched between {alpha}-emitting source material and low-Z target material), and ({alpha},n) reactions induced by a monoenergetic beam of {alpha}-particles incident on a slab of target material. Spontaneous fission spectra are calculated with evaluated half-life, spontaneous fission branching, and Watt spectrum parameters for 43 actinides. The ({alpha},n) spectra are calculated using an assumed isotropic angular distribution in the center-of-mass system with a library of 89 nuclide decay {alpha}-particle spectra, 24 sets of measured and/or evaluated ({alpha},n) cross sections and product nuclide level branching fractions, and functional {alpha}-particle stopping cross sections for Z < 106. The delayed neutron spectra are taken from an evaluated library of 105 precursors. The code outputs the magnitude and spectra of the resultant neutron source. It also provides an analysis of the contributions to that source by each nuclide in the problem.

  7. Price Quotes and Isotope Ordering

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

    Ordering Price Quotes and Isotope Ordering Isotopes produced at Los Alamos National Laboratory are saving lives, advancing cutting-edge research and keeping the U.S. safe. Isotope...

  8. Discovery of the Indium Isotopes

    E-Print Network [OSTI]

    S. Amos; M. Thoennessen

    2010-09-08

    Thirty-eight indium isotopes (A = 98-135) have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  9. Discovery of the Titanium Isotopes

    E-Print Network [OSTI]

    D. Meierfrankenfeld; M. Thoennessen

    2010-09-08

    Twentyfive titanium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  10. Discovery of the Mercury Isotopes

    E-Print Network [OSTI]

    D. Meierfrankenfeld; M. Thoennessen

    2010-09-08

    Forty mercury isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  11. Discovery of the Cobalt Isotopes

    E-Print Network [OSTI]

    T. Szymanski; M. Thoennessen

    2009-09-04

    Twenty-six cobalt isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  12. Discovery of the Tin Isotopes

    E-Print Network [OSTI]

    S. Amos; M. Thoennessen

    2010-09-08

    Thirty-eight tin isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  13. Discovery of the Cadmium Isotopes

    E-Print Network [OSTI]

    S. Amos; M. Thoennessen

    2009-10-22

    Thirty-seven cadmium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  14. (Carbon isotope fractionation inplants)

    SciTech Connect (OSTI)

    O'Leary, M.H.

    1990-01-01

    The objectives of this research are: To develop a theoretical and experimental framework for understanding isotope fractionations in plants; and to develop methods for using this isotope fractionation for understanding the dynamics of CO{sub 2} fixation in plants. Progress is described.

  15. Photochemical isotope separation

    DOE Patents [OSTI]

    Robinson, C.P.; Jensen, R.J.; Cotter, T.P.; Greiner, N.R.; Boyer, K.

    1987-04-28

    A process is described for separating isotopes by selective excitation of isotopic species of a volatile compound by tuned laser light. A highly cooled gas of the volatile compound is produced in which the isotopic shift is sharpened and defined. Before substantial condensation occurs, the cooled gas is irradiated with laser light precisely tuned to a desired wavelength to selectively excite a particular isotopic species in the cooled gas. The laser light may impart sufficient energy to the excited species to cause it to undergo photochemical reaction or even to photoionize. Alternatively, a two-photon irradiation may be applied to the cooled gas to induce photochemical reaction or photoionization. The process is particularly applicable to the separation of isotopes of uranium and plutonium. 8 figs.

  16. Laser isotope separation

    DOE Patents [OSTI]

    Robinson, C. Paul (Los Alamos, NM); Jensen, Reed J. (Los Alamos, NM); Cotter, Theodore P. (Munich, DE); Boyer, Keith (Los Alamos, NM); Greiner, Norman R. (Los Alamos, NM)

    1988-01-01

    A process and apparatus for separating isotopes by selective excitation of isotopic species of a volatile compound by tuned laser light. A highly cooled gas of the volatile compound is produced in which the isotopic shift is sharpened and defined. Before substantial condensation occurs, the cooled gas is irradiated with laser light precisely tuned to a desired wavelength to selectively excite a particular isotopic species in the cooled gas. The laser light may impart sufficient energy to the excited species to cause it to undergo photolysis, photochemical reaction or even to photoionize. Alternatively, a two-photon irradiation may be applied to the cooled gas to induce photolysis, photochemical reaction or photoionization. The process is particularly applicable to the separation of isotopes of uranium.

  17. SOURCES 4C : a code for calculating ([alpha],n), spontaneous fission, and delayed neutron sources and spectra.

    SciTech Connect (OSTI)

    Wilson, W. B. (William B.); Perry, R. T. (Robert T.); Shores, E. F. (Erik F.); Charlton, W. S. (William S.); Parish, Theodore A.; Estes, G. P. (Guy P.); Brown, T. H. (Thomas H.); Arthur, Edward D. (Edward Dana),; Bozoian, Michael; England, T. R.; Madland, D. G.; Stewart, J. E. (James E.)

    2002-01-01

    SOURCES 4C is a computer code that determines neutron production rates and spectra from ({alpha},n) reactions, spontaneous fission, and delayed neutron emission due to radionuclide decay. The code is capable of calculating ({alpha},n) source rates and spectra in four types of problems: homogeneous media (i.e., an intimate mixture of a-emitting source material and low-Z target material), two-region interface problems (i.e., a slab of {alpha}-emitting source material in contact with a slab of low-Z target material), three-region interface problems (i.e., a thin slab of low-Z target material sandwiched between {alpha}-emitting source material and low-Z target material), and ({alpha},n) reactions induced by a monoenergetic beam of {alpha}-particles incident on a slab of target material. Spontaneous fission spectra are calculated with evaluated half-life, spontaneous fission branching, and Watt spectrum parameters for 44 actinides. The ({alpha},n) spectra are calculated using an assumed isotropic angular distribution in the center-of-mass system with a library of 107 nuclide decay {alpha}-particle spectra, 24 sets of measured and/or evaluated ({alpha},n) cross sections and product nuclide level branching fractions, and functional {alpha}-particle stopping cross sections for Z < 106. The delayed neutron spectra are taken from an evaluated library of 105 precursors. The code provides the magnitude and spectra, if desired, of the resultant neutron source in addition to an analysis of the'contributions by each nuclide in the problem. LASTCALL, a graphical user interface, is included in the code package.

  18. Visible light surface emitting semiconductor laser

    DOE Patents [OSTI]

    Olbright, Gregory R. (Boulder, CO); Jewell, Jack L. (Bridgewater, NJ)

    1993-01-01

    A vertical-cavity surface-emitting laser is disclosed comprising a laser cavity sandwiched between two distributed Bragg reflectors. The laser cavity comprises a pair of spacer layers surrounding one or more active, optically emitting quantum-well layers having a bandgap in the visible which serve as the active optically emitting material of the device. The thickness of the laser cavity is m .lambda./2n.sub.eff where m is an integer, .lambda. is the free-space wavelength of the laser radiation and n.sub.eff is the effective index of refraction of the cavity. Electrical pumping of the laser is achieved by heavily doping the bottom mirror and substrate to one conductivity-type and heavily doping regions of the upper mirror with the opposite conductivity type to form a diode structure and applying a suitable voltage to the diode structure. Specific embodiments of the invention for generating red, green, and blue radiation are described.

  19. Progress on Production of Alpha-emitting Radioisotopes for Cancer Therapy |

    Office of Science (SC) Website

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe 26thIWalter H.4 »Programming Challenges Workshop AdvancedU.S.

  20. Physics with Rare Isotope Beams

    SciTech Connect (OSTI)

    Segel, Ralph E. [Northwestern University] [Northwestern University

    2013-11-08

    Using stable and radioactive beams provided by ATLAS nuclear reactions of special interest in astrophysics have been studied with emphasis on breakout from the hot CNO cycle to the rp-process. The masses of nuclear fragments provided by a strong fission source have been measured in order to help trace the path of the r process. 8Li ions produced by the d(7Li,8Li)n reaction have been trapped and the electrons and alphas emitted in the ensuing beta-decay measured. The neutrino directions were therefore determined, which leads to a measurement of the electron-neutrino correlation. The energies and kinematics are such that a sensitive search for any tensor admixture could be performed and an upper limit of 0.6% was placed on any such admixture. Earlier work on the electromagnetic form factors of the proton was extended. Graduate students were active participants in all of these eperiments, which formed the basis for six PhD theses.

  1. Surface plasmonpolariton mediated emission of light from top-emitting organic light-emitting diode type structures

    E-Print Network [OSTI]

    Exeter, University of

    .60.Jb; 72.80.Le Keywords: Surface plasmons; Organic light-emitting diodes (OLEDs); Microstructure 1Surface plasmon­polariton mediated emission of light from top-emitting organic light-emitting diode as significant loss channels in organic light-emitting diode devices. We present experimental data illustrating

  2. Atomic vapor laser isotope separation

    SciTech Connect (OSTI)

    Stern, R.C.; Paisner, J.A.

    1986-08-15

    The atomic vapor laser isotope separation (AVLIS) process for the enrichment of uranium is evaluated. (AIP)

  3. Surface alpha clustering

    SciTech Connect (OSTI)

    Rotter, I.

    1983-05-01

    The problem of alpha decay is discussed on the basis of a theory which describes discrete and continuous states in a unified manner. A formula for numerical calculations is given in which configurational mixing as well as channel coupling is taken into account. The R-matrix approximation is shown to be justified if the width is spread over a small number of decay channels. Generally, renormalization of the wave function is necessary if a factorization of the width is assumed. The importance of channel coupling for the case of a small reduced width is discussed.

  4. Gamma-Ray Library and Uncertainty Analysis: Passively Emitted Gamma Rays Used in Safeguards Technology

    SciTech Connect (OSTI)

    Parker, W

    2009-09-18

    Non-destructive gamma-ray analysis is a fundamental part of nuclear safeguards, including nuclear energy safeguards technology. Developing safeguards capabilities for nuclear energy will certainly benefit from the advanced use of gamma-ray spectroscopy as well as the ability to model various reactor scenarios. There is currently a wide variety of nuclear data that could be used in computer modeling and gamma-ray spectroscopy analysis. The data can be discrepant (with varying uncertainties), and it may difficult for a modeler or software developer to determine the best nuclear data set for a particular situation. To use gamma-ray spectroscopy to determine the relative isotopic composition of nuclear materials, the gamma-ray energies and the branching ratios or intensities of the gamma-rays emitted from the nuclides in the material must be well known. A variety of computer simulation codes will be used during the development of the nuclear energy safeguards, and, to compare the results of various codes, it will be essential to have all the {gamma}-ray libraries agree. Assessing our nuclear data needs allows us to create a prioritized list of desired measurements, and provides uncertainties for energies and especially for branching intensities. Of interest are actinides, fission products, and activation products, and most particularly mixtures of all of these radioactive isotopes, including mixtures of actinides and other products. Recent work includes the development of new detectors with increased energy resolution, and studies of gamma-rays and their lines used in simulation codes. Because new detectors are being developed, there is an increased need for well known nuclear data for radioactive isotopes of some elements. Safeguards technology should take advantage of all types of gamma-ray detectors, including new super cooled detectors, germanium detectors and cadmium zinc telluride detectors. Mixed isotopes, particularly mixed actinides found in nuclear reactor streams can be especially challenging to identify. The super cooled detectors have a marked improvement in energy resolution, allowing the possibility of deconvolution of mixtures of gamma rays that was unavailable with high purity germanium detectors. Isotopic analysis codes require libraries of gamma rays. In certain situations, isotope identification can be made in the field, sometimes with a short turnaround time, depending on the choice of detector and software analysis package. Sodium iodide and high purity germanium detectors have been successfully used in field scenarios. The newer super cooled detectors offer dramatically increased resolution, but they have lower efficiency and so can require longer collection times. The different peak shapes require software development for the specific detector type and field application. Libraries can be tailored to specific scenarios; by eliminating isotopes that are certainly not present, the analysis time may be shortened and the accuracy may be increased. The intent of this project was to create one accurate library of gamma rays emitted from isotopes of interest to be used as a reliable reference in safeguards work. All simulation and spectroscopy analysis codes can draw upon this best library to improve accuracy and cross-code consistency. Modeling codes may include MCNP and COG. Gamma-ray spectroscopy analysis codes may include MGA, MGAU, U235 and FRAM. The intent is to give developers and users the tools to use in nuclear energy safeguards work. In this project, the library created was limited to a selection of actinide isotopes of immediate interest to reactor technology. These isotopes included {sup 234-238}U, {sup 237}Np, {sup 238-242}Pu, {sup 241,243}Am and {sup 244}Cm. These isotopes were examined, and the best of gamma-ray data, including line energies and relative strengths were selected.

  5. Perchlorate Isotope Forensics

    SciTech Connect (OSTI)

    Bohlke, J. K. [U.S. Geological Survey, Reston, VA; Sturchio, N. C. [University of Illinois, Chicago; Gu, Baohua [ORNL; Horita, Juske [ORNL; Brown, Gilbert M [ORNL; Jackson, W. Andrew [Tennessee Technological University; Batista, Jacimaria [University of Nevada, Las Vegas

    2006-01-01

    Perchlorate has been detected recently in a variety of soils, waters, plants, and food products at levels that may be detrimental to human health. These discoveries have generated considerable interest in perchlorate source identification. In this study, comprehensive stable isotope analyses ({sup 37}Cl/{sup 35}Cl and {sup 18}O/{sup 17}O/{sup 16}O) of perchlorate from known synthetic and natural sources reveal systematic differences in isotopic characteristics that are related to the formation mechanisms. In addition, isotopic analyses of perchlorate extracted from groundwater and surface water demonstrate the feasibility of identifying perchlorate sources in contaminated environments on the basis of this technique. Both natural and synthetic sources of perchlorate have been identified in water samples from some perchlorate occurrences in the United States by the isotopic method.

  6. Plasma isotope separation methods

    SciTech Connect (OSTI)

    Grossman, M.W. ); Shepp, T.A. )

    1991-12-01

    Isotope separation has many important industrial, medical, and research applications. Large-scale processes have typically utilized complex cascade systems; for example, the gas centrifuge. Alternatively, high single-stage enrichment processes (as in the case of the calutron) are very energy intensive. Plasma-based methods being developed for the past 15 to 20 years have attempted to overcome these two drawbacks. In this review, six major types of isotope separation methods which involve plasma phenomena are discussed. These methods are: plasma centrifuge, AVLIS (atomic vapor laser isotope separation), ion wave, ICR (ion-cyclotron resonance), calutron, and gas discharge. The emphasis of this paper is to describe the plasma phenomena in these major categories. An attempt was made to include enough references so that more detailed study or evaluation of a particular method could readily be pursued. A brief discussion of isotope separation using mass balance concepts is also carried out.

  7. On the Lyman-alpha Emission of Starburst Galaxies

    E-Print Network [OSTI]

    David Valls-Gabaud

    1993-06-13

    Nearby starburst galaxies have consistently shown anomalous Ly-alpha/H-beta ratios. By re-analysing the published IUE/optical observations, we show that most starbursts present a normal Ly-alpha emission, consistent with case B recombination theory, provided extinction laws appropriate to their metallicities are used. This implies that extinction is more important than multiple resonant scattering effects. The anomalous emission and absorption lines present in a few remaining galaxies are simply explained if they are observed in the post-burst phase, between about 10$^7$ and 10$^8$ yrs after the start of the burst. We use updated stellar population synthesis models to show that anomalous ratios are produced by the aging of stellar populations, since the underlying stellar Ly-alpha line is important in the cooler massive stars. The inferred low-duty cycle of massive star formation accounts naturally for the failure to detect large numbers of Ly-alpha--emitting galaxies in deep surveys and at high redshift. Some testable predictions of the proposed scenario are also discussed.

  8. Chromium Isotope Fractionation During Reduction of Cr(VI) Under Saturated Flow Conditions

    SciTech Connect (OSTI)

    Jamieson-Hanes, Julia H.; Gibson, Blair D.; Lindsay, Matthew B.J.; Kim, Yeongkyoo; Ptacek, Carol J.; Blowes, David W.

    2012-10-25

    Chromium isotopes are potentially useful indicators of Cr(VI) reduction reactions in groundwater flow systems; however, the influence of transport on Cr isotope fractionation has not been fully examined. Laboratory batch and column experiments were conducted to evaluate isotopic fractionation of Cr during Cr(VI) reduction under both static and controlled flow conditions. Organic carbon was used to reduce Cr(VI) in simulated groundwater containing 20 mg L{sup -1} Cr(VI) in both batch and column experiments. Isotope measurements were performed on dissolved Cr on samples from the batch experiments, and on effluent and profile samples from the column experiment. Analysis of the residual solid-phase materials by scanning electron microscopy (SEM) and by X-ray absorption near edge structure (XANES) spectroscopy confirmed association of Cr(III) with organic carbon in the column solids. Decreases in dissolved Cr(VI) concentrations were coupled with increases in {delta}{sup 53}Cr, indicating that Cr isotope enrichment occurred during reduction of Cr(VI). The {delta}{sup 53}Cr data from the column experiment was fit by linear regression yielding a fractionation factor ({alpha}) of 0.9979, whereas the batch experiments exhibited Rayleigh-type isotope fractionation ({alpha} = 0.9965). The linear characteristic of the column {delta}{sup 53}Cr data may reflect the contribution of transport on Cr isotope fractionation.

  9. Isotope effect studies of the pyridoxal 5'-phosphate dependent histidine decarboxylase from Morganella morganii

    SciTech Connect (OSTI)

    Abell, L.M.; O'Leary, M.H.

    1988-08-09

    The pyridoxal 5'-phosphate dependent histidine decarboxylase from Morganella morganii shows a nitrogen isotope effect k/sup 14//k/sup 15/ = 0.9770 +/- 0.0021, a carbon isotope effect k/sup 12//k/sup 13/ = 1.0308 +/- 0.0006, and a carbon isotope effect for L-(..cap alpha..-/sup 2/H)histidine of 1.0333 +/- 0.0001 at pH 6.3, 37/sup 0/C. These results indicate that the overall decarboxylation rate is limited jointly by the rate of Schiff base interchange and by the rate of decarboxylation. Although the observed isotope effects are quite different from those for the analogous glutamate decarboxylase from Escherichia coli, the intrinsic isotope effects for the two enzymes are essentially the same. The difference in observed isotope effects occurs because of a roughly twofold difference in the partitioning of the pyridoxal 5'-phosphate-substrate Schiff base between decarboxylation and Schiff base interchange. The observed nitrogen isotope effect requires that the imine nitrogen in this Schiff base is protonated. Comparison of carbon isotope effects for deuteriated and undeuteriated substrates reveals that the deuterium isotope effect on the decarboxylation step is about 1.20; thus, in the transition state for the decarboxylation step, the carbon-carbon bond is about two-thirds broken.

  10. Method of making organic light emitting devices

    DOE Patents [OSTI]

    Shiang, Joseph John (Niskayuna, NY); Janora, Kevin Henry (Schenectady, NY); Parthasarathy, Gautam (Saratoga Springs, NY); Cella, James Anthony (Clifton Park, NY); Chichak, Kelly Scott (Clifton Park, NY)

    2011-03-22

    The present invention provides a method for the preparation of organic light-emitting devices comprising a bilayer structure made by forming a first film layer comprising an electroactive material and an INP precursor material, and exposing the first film layer to a radiation source under an inert atmosphere to generate an interpenetrating network polymer composition comprising the electroactive material. At least one additional layer is disposed on the reacted first film layer to complete the bilayer structure. The bilayer structure is comprised within an organic light-emitting device comprising standard features such as electrodes and optionally one or more additional layers serving as a bipolar emission layer, a hole injection layer, an electron injection layer, an electron transport layer, a hole transport layer, exciton-hole transporting layer, exciton-electron transporting layer, a hole transporting emission layer, or an electron transporting emission layer.

  11. Transportation of medical isotopes

    SciTech Connect (OSTI)

    Nielsen, D.L.

    1997-11-19

    A Draft Technical Information Document (HNF-1855) is being prepared to evaluate proposed interim tritium and medical isotope production at the Fast Flux Test Facility (FFTF). This assessment examines the potential health and safety impacts of transportation operations associated with the production of medical isotopes. Incident-free and accidental impacts are assessed using bounding source terms for the shipment of nonradiological target materials to the Hanford Site, the shipment of irradiated targets from the FFTF to the 325 Building, and the shipment of medical isotope products from the 325 Building to medical distributors. The health and safety consequences to workers and the public from the incident-free transportation of targets and isotope products would be within acceptable levels. For transportation accidents, risks to works and the public also would be within acceptable levels. This assessment is based on best information available at this time. As the medical isotope program matures, this analysis will be revised, if necessary, to support development of a final revision to the Technical Information Document.

  12. High-Performance Organic Light-Emitting Diodes Using ITO

    E-Print Network [OSTI]

    Ho, Seng-Tiong

    High-Performance Organic Light-Emitting Diodes Using ITO Anodes Grown on Plastic by Room,* Mark E. Madsen, Antonio DiVenere, and Seng-Tiong Ho Organic light-emitting diodes (OLEDs) fabricated

  13. Thermo-electrically pumped semiconductor light emitting diodes

    E-Print Network [OSTI]

    Santhanam, Parthiban

    2014-01-01

    Thermo-electric heat exchange in semiconductor light emitting diodes (LEDs) allows these devices to emit optical power in excess of the electrical power used to drive them, with the remaining power drawn from ambient heat. ...

  14. Applied Radiation and Isotopes 55 (2001) 707713 Bronchial dosimeter for radon progeny

    E-Print Network [OSTI]

    Yu, Peter K.N.

    2001-01-01

    Applied Radiation and Isotopes 55 (2001) 707­713 Bronchial dosimeter for radon progeny T June 2001 Abstract A true bronchial dosimeter has been designed, consisting of four 400-mesh wire. In this way, the bronchial dosimeter directly gives bronchial dose from the alpha counts recorded on the wire

  15. Oxycarbonitride phosphors and light emitting devices using the same

    DOE Patents [OSTI]

    Li, Yuanqiang; Romanelli, Michael D.; Tian, Yongchi

    2015-12-22

    A family of oxycarbonitride phosphor compositions is provided. Also provided are light emitting devices incorporating the oxycarbonitride phosphor compositions.

  16. Aalborg Universitet Water cooling of high power light emitting diode

    E-Print Network [OSTI]

    Berning, Torsten

    Aalborg Universitet Water cooling of high power light emitting diode Sørensen, Henrik Published in Citation for published version (APA): Sørensen, H. (2012). Water cooling of high power light emitting diode from vbn.aau.dk on: juli 07, 2015 #12;Water Cooling of High Power Light Emitting Diode Henrik Sørensen

  17. Organic Light-Emitting Diodes Having Carbon Nanotube Anodes

    E-Print Network [OSTI]

    Gruner, George

    , flexible anodes for organic light-emitting diodes (OLEDs). For polymer-based OLEDs having the structure applications. Polymer and small molecule-based organic light-emitting diodes (OLEDs) are rapidly approachingOrganic Light-Emitting Diodes Having Carbon Nanotube Anodes Jianfeng Li, Liangbing Hu, Lian Wang

  18. Method for separating boron isotopes

    DOE Patents [OSTI]

    Rockwood, Stephen D. (Los Alamos, NM)

    1978-01-01

    A method of separating boron isotopes .sup.10 B and .sup.11 B by laser-induced selective excitation and photodissociation of BCl.sub.3 molecules containing a particular boron isotope. The photodissociation products react with an appropriate chemical scavenger and the reaction products may readily be separated from undissociated BCl.sub.3, thus effecting the desired separation of the boron isotopes.

  19. Binding Energies of the Alpha Particle and the A=3 Isobars from a Theoretical Geometric Model

    E-Print Network [OSTI]

    Gustavo R. Gonzalez-Martin

    2008-05-03

    We assume a triple geometric structure for the electromagnetic nuclear interaction. This nuclear electromagnetism is used to calculate the binding energies of the alpha particle and the A=3 isobar nuclides. The approximation for the resultant wave equation which lead to the deuteron binding energy from the modified Mathieu equation for the radial eigenvalue equation also establishes proton-electron-proton magnetic bonds in these nuclides and determines their binding energies. Completely theoretical calculations give 28.5 Mev., 7.64 Mev. and 8.42 Mev. for the binding energies of the alpha particle, the helium 3 isotope and tritium respectively. These values admit correction factors due to the approximations made.

  20. Isotop kl. B Supportlab.

    E-Print Network [OSTI]

    Isotop kl. B lab. Nærlager Supportlab. Supportlab. Supportlab. Lab. GMO1/BSL2 Supportlab. Supportlab. Supportlab. Supportlab. Lab. GMO1/BSL2 Vareindlevering post/frost Kontor Sofastue / Thekøkken. GMO1/BSL2 Supportlab. �velseslab, eksist. �velseslab, eksist. Forberedelseslab. Rum, køl/ centrifuge

  1. A micrometer-size movable light emitting area in a resonant tunneling light emitting diode

    SciTech Connect (OSTI)

    Pettinari, G., E-mail: giorgio.pettinari@cnr.it [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom); National Research Council (CNR), Institute for Photonics and Nanotechnologies (IFN-CNR), Via Cineto Romano 42, 00156 Roma (Italy); Balakrishnan, N.; Makarovsky, O.; Campion, R. P.; Patanè, A. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)] [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Polimeni, A.; Capizzi, M. [CNISM-Dipartimento di Fisica, Sapienza Università di Roma, P.le A. Moro 2, 00185 Roma (Italy)] [CNISM-Dipartimento di Fisica, Sapienza Università di Roma, P.le A. Moro 2, 00185 Roma (Italy)

    2013-12-09

    We report on the fabrication of a micrometer-size movable light emitting area in a GaAs/AlAs quantum well resonant tunneling p-i-n diode. The spatial position of the micrometer-size light emitting area shifts linearly with increasing applied bias, up to 30??m for a bias increment of 0.2?V. Also, the simultaneous resonant tunneling injection of both electrons and holes into the quantum well states is achieved at specific positions of the diode, thus resulting in a tenfold increase of the electroluminescence intensity.

  2. Tunable, superconducting, surface-emitting teraherz source

    DOE Patents [OSTI]

    Welp, Ulrich (Lisle, IL); Koshelev, Alexei E. (Bolingbrook, IL); Gray, Kenneth E. (Evanston, IL); Kwok, Wai-Kwong (Evanston, IL); Vlasko-Vlasov, Vitalii (Downers Grove, IL)

    2009-10-27

    A compact, solid-state THz source based on the driven Josephson vortex lattice in a highly anisotropic superconductor such as Bi.sub.2Sr.sub.2CaCu.sub.2O.sub.8 that allows cw emission at tunable frequency. A second order metallic Bragg grating is used to achieve impedance matching and to induce surface emission of THz-radiation from a Bi.sub.2Sr.sub.2CaCu.sub.2O.sub.8 sample. Steering of the emitted THz beam is accomplished by tuning the Josephson vortex spacing around the grating period using a superimposed magnetic control field.

  3. Tunable, superconducting, surface-emitting teraherz source

    DOE Patents [OSTI]

    Welp, Ulrich; Koshelev, Alexei E.; Gray, Kenneth E.; Kwok, Wai-Kwong; Vlasko-Vlasov, Vitalii

    2010-05-11

    A compact, solid-state THz source based on the driven Josephson vortex lattice in a highly anisotropic superconductor such as Bi.sub.2Sr.sub.2CaCu.sub.2O.sub.8 that allows cw emission at tunable frequency. A second order metallic Bragg grating is used to achieve impedance matching and to induce surface emission of THz-radiation from a Bi.sub.2Sr.sub.2CaCu.sub.2O.sub.8 sample. Steering of the emitted THz beam is accomplished by tuning the Josephson vortex spacing around the grating period using a superimposed magnetic control field.

  4. Supported palladium materials for isotope separation

    SciTech Connect (OSTI)

    Rutherford, W.M.; Ellis, R.E.; Abell, G.C.

    1988-01-21

    Several palladium packing materials were investigated for their suitability for use in the separation of hydrogen isotopes by displacement chromatography. The materials included palladium on Chromosorb and several formulations of palladium on commercially available alpha-alumina-based catalyst supports. All materials showed some degradation upon being subjected to repeated hydriding-dehydriding cycles; however, the degradation did not lead to unacceptably low permeability to gas flow. Dynamic performance of the packings was evaluated by displacement of deuterium with protium at several temperatures and flow rates. Isotopic exchange was generally rapid. However, high surface area packings (greater than 4 m/sup 2//g) yielded transition zones that were initially sharp, but had long ''tails'' at deuterium concentrations below 5%. Best results were obtained with a packing containing 48.2% palladium on Norton catalyst support No. SA5*21 (surface area = 0.33 m/sup 2//g). Improved performance was observed as the displacement temperature was increased to 80/sup 0/C from 22/sup 0/C. The slight decrease in equilibrium separation was more than offset by improved kinetics at the higher temperature. 19 figs., 6 tabs.

  5. ALPHA-PARTICLE RADIOBIOLOGICAL EXPERIMENTS USING THIN CR-39 DETECTORS

    E-Print Network [OSTI]

    Yu, Peter K.N.

    sterilisation. For alpha-particle radiobiological experiments, it is easier to quantify the alpha energies

  6. White emitting polyfluorene functionalized with azide hybridized on near-UV light emitting diode

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    . Griffin, C. W. Jeon, and M. D. Dawson, "Spectral conversion of InGaN ultraviolet microarray light functionalization to facilitate cross-linking intentionally when cast into solid-state form. Hybridized on n-UV InGaN/Ga generation using CdSe/ZnS core-shell nanocrystals hybridized with InGaN/GaN light emitting diodes

  7. Nuclear Reactions Important in Alpha-Rich Freezeouts

    E-Print Network [OSTI]

    G. C. Jordan IV; S. S. Gupta; B. S. Meyer; L. -S. The

    2002-11-08

    The alpha-rich freezeout from equilibrium occurs during the core-collapse explosion of a massive star when the supernova shock wave passes through the Si-rich shell of the star. The nuclei are heated to high temperature and broken down into nucleons and alpha particles. These subsequently reassemble as the material expands and cools, thereby producing new heavy nuclei, including a number of important supernova observables. In this paper we introduce two web-based applications. The first displays the results of a reaction-rate sensitivity study of alpha-rich freezeout yields. The second allows the interested reader to run paramaterized explosive silicon burning calculations in which the user inputs his own parameters. These tools are intended to aid in the identification of nuclear reaction rates important for experimental study. We then analyze several iron-group isotopes (59Ni, 57Co, 56Co, and 55Fe) in terms of their roles as observables and examine the reaction rates that are important in their production.

  8. Laser isotope separation of erbium and other isotopes

    DOE Patents [OSTI]

    Haynam, C.A.; Worden, E.F.

    1995-08-22

    Laser isotope separation is accomplished using at least two photoionization pathways of an isotope simultaneously, where each pathway comprises two or more transition steps. This separation method has been applied to the selective photoionization of erbium isotopes, particularly for the enrichment of {sup 167}Er. The hyperfine structure of {sup 167}Er was used to find two three-step photoionization pathways having a common upper energy level. 3 figs.

  9. Laser isotope separation of erbium and other isotopes

    DOE Patents [OSTI]

    Haynam, Christopher A. (3035 Ferdale Ct., Pleasanton, CA 94566); Worden, Earl F. (117 Vereda del Ciervo, Diablo, CA 94528)

    1995-01-01

    Laser isotope separation is accomplished using at least two photoionization pathways of an isotope simultaneously, where each pathway comprises two or more transition steps. This separation method has been applied to the selective photoionization of erbium isotopes, particularly for the enrichment of .sup.167 Er. The hyperfine structure of .sup.167 Er was used to find two three-step photoionization pathways having a common upper energy level.

  10. Isotope separation with the RICH detector of the AMS Experiment

    E-Print Network [OSTI]

    Arruda, Luísa; Borges, João; Carmo, Fernando; Gonçalves, Patrícia; Pereira, Rui; Pimenta, Mário

    2007-01-01

    The Alpha Magnetic Spectrometer (AMS), to be installed on the International Space Station (ISS) in 2008, is a cosmic ray detector with several subsystems, one of which is a proximity focusing Ring Imaging Cherenkov (RICH) detector. This detector will be equipped with a dual radiator (aerogel+NaF), a lateral conical mirror and a detection plane made of 680 photomultipliers and light guides, enabling precise measurements of particle electric charge and velocity. Combining velocity measurements with data on particle rigidity from the AMS Tracker it is possible to obtain a measurement for particle mass, allowing the separation of isotopes. A Monte Carlo simulation of the RICH detector, based on realistic properties measured at ion beam tests, was performed to evaluate isotope separation capabilities. Results for three elements -- H (Z=1), He (Z=2) and Be (Z=4) -- are presented.

  11. Isotope separation with the RICH detector of the AMS Experiment

    E-Print Network [OSTI]

    Luísa Arruda; Fernando Barão; João Borges; Fernando Carmo; Patrícia Gonçalves; Rui Pereira; Mário Pimenta

    2007-10-03

    The Alpha Magnetic Spectrometer (AMS), to be installed on the International Space Station (ISS) in 2008, is a cosmic ray detector with several subsystems, one of which is a proximity focusing Ring Imaging Cherenkov (RICH) detector. This detector will be equipped with a dual radiator (aerogel+NaF), a lateral conical mirror and a detection plane made of 680 photomultipliers and light guides, enabling precise measurements of particle electric charge and velocity. Combining velocity measurements with data on particle rigidity from the AMS Tracker it is possible to obtain a measurement for particle mass, allowing the separation of isotopes. A Monte Carlo simulation of the RICH detector, based on realistic properties measured at ion beam tests, was performed to evaluate isotope separation capabilities. Results for three elements -- H (Z=1), He (Z=2) and Be (Z=4) -- are presented.

  12. Electron emitting filaments for electron discharge devices

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Pincosy, Philip A. (Oakland, CA); Ehlers, Kenneth W. (Alamo, CA)

    1988-01-01

    Electrons are copiously emitted by a device comprising a loop-shaped filament made of lanthanum hexaboride. The filament is directly heated by an electrical current produced along the filament by a power supply connected to the terminal legs of the filament. To produce a filament, a diamond saw or the like is used to cut a slice from a bar made of lanthanum hexaboride. The diamond saw is then used to cut the slice into the shape of a loop which may be generally rectangular, U-shaped, hairpin-shaped, zigzag-shaped, or generally circular. The filaments provide high electron emission at a relatively low operating temperature, such as 1600.degree. C. To achieve uniform heating, the filament is formed with a cross section which is tapered between the opposite ends of the filament to compensate for non-uniform current distribution along the filament due to the emission of electrons from the filament.

  13. Electron emitting filaments for electron discharge devices

    DOE Patents [OSTI]

    Leung, K.N.; Pincosy, P.A.; Ehlers, K.W.

    1983-06-10

    Electrons are copiously emitted by a device comprising a loop-shaped filament made of lanthanum hexaboride. The filament is directly heated by an electrical current produced along the filament by a power supply connected to the terminal legs of the filament. To produce a filament, a diamond saw or the like is used to cut a slice from a bar made of lanthanum hexaboride. The diamond saw is then used to cut the slice into the shape of a loop which may be generally rectangular, U-shaped, hairpin-shaped, zigzag-shaped, or generally circular. The filaments provide high electron emission at a relatively low operating temperature, such as 1600/sup 0/C. To achieve uniform heating, the filament is formed with a cross section which is tapered between the opposite ends of the filament to compensate for nonuniform current distribution along the filament due to the emission of electrons from the filament.

  14. Ionic liquid polyoxometalates as light emitting materials

    SciTech Connect (OSTI)

    Ortiz-acosta, Denisse [Los Alamos National Laboratory; Del Sesto, Rico E [Los Alamos National Laboratory; Scott, Brian [Los Alamos National Laboratory; Bennett, Bryan L [Los Alamos National Laboratory; Purdy, Geraldine M [Los Alamos National Laboratory; Muenchausen, Ross E [Los Alamos National Laboratory; Mc Kigney, Edward [Los Alamos National Laboratory; Gilbertson, Robert [Los Alamos National Laboratory

    2008-01-01

    The low melting point, negligible vapor pressure, good solubility, and thermal and chemical stability make ionic liquids useful materials for a wide variety of applications. Polyoxometalates are early transition metal oxygen clusters that can be synthesized in many different sizes and with a variety of heterometals. The most attractive feature of POMs is that their physical properties, in particular electrical, magnetic, and optical properties, can be easily modified following known procedures. It has been shown that POMs can exhibit cooperative properties, as superconductivity and energy transfer. POM ionic liquids can be obtained by selecting the appropliate cation. Different alkyl ammonium and alkyl phosphonium salts are being used to produce new POM ionic liquids together with organic or inorganic luminescent centers to design light emitting materials. Ammonium and phosphonium cations with activated, polymerizable groups are being used to further polymerize the ionic liquid into transparent, solid materials with high metal density.

  15. Tightly Correlated X-ray/H$?$ Emitting Filaments in the Superbubble and Large-Scale Superwind of NGC 3079

    E-Print Network [OSTI]

    G. Cecil; J. Bland-Hawthorn; S. Veilleux

    2002-05-29

    Using Chandra and HST we show that X-ray and H$\\alpha$ filaments that form the 1.3-kpc diameter superbubble of NGC 3079 have strikingly similar patterns at 0."8 resolution. This tight match seems to arise from cool disk gas that has been driven by the wind, with X-rays being emitted from upstream, stand-off bowshocks or by conductive cooling at the cloud/wind interfaces. We find that the soft X-ray plasma has thermal and kinetic energies of $2\\times10^{56}\\sqrt{\\eta_x}$ and $5\\times10^{54}\\sqrt{\\eta_X}$ erg respectively, where $\\eta_X$ is the filling factor of the X-ray gas and may be small; these are comparable to the energies of the optical line-emitting gas. X-rays are also seen from the base of the radio counterbubble that is obscured optically by the galaxy disk, and from the nucleus (whose spectrum shows the Fe K$\\alpha$ line). Hydrodynamical simulations reproduce the obbservations well using large filling factors within both filament systems; assuming otherwise seriously underestimates the mass loss in the superwind. The superbubble is surrounded by a fainter conical halo of X-rays that fill the area delineated by high angle, H$\\alpha$-emitting filaments, supporting our previous assertion that these filaments form the contact discontinuity/shock between galaxy gas and shocked wind. About 40\\arcsec (3 kpc) above the disk, an X-ray arc may partially close beyond the bubble, but the north-east quadrant remains open, consistent with the superwind having broken out into at least the galaxy halo.

  16. Light emitting device comprising phosphorescent materials for white light generation

    DOE Patents [OSTI]

    Thompson, Mark E.; Dapkus, P. Daniel

    2014-07-22

    The present invention relates to phosphors for energy downconversion of high energy light to generate a broadband light spectrum, which emit light of different emission wavelengths.

  17. Demonstration Assessment of Light-Emitting Diode (LED) Street...

    Office of Scientific and Technical Information (OSTI)

    Street Lighting Host Site: Lija Loop, Portland, Oregon Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Street Lighting Host Site:...

  18. Demonstration Assessment of Light-Emitting Diode Parking Structure...

    Office of Scientific and Technical Information (OSTI)

    Parking Structure Lighting at U.S. Department of Labor Headquarters Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode Parking Structure...

  19. Isotopically labeled compositions and method

    DOE Patents [OSTI]

    Schmidt, Jurgen G. (Los Alamos, NM); Kimball, David B. (Los Alamos, NM); Alvarez, Marc A. (Santa Fe, NM); Williams, Robert F. (Los Alamos, NM); Martinez, Rudolfo A. (Santa Fe, NM)

    2011-07-12

    Compounds having stable isotopes .sup.13C and/or .sup.2H were synthesized from precursor compositions having solid phase supports or affinity tags.

  20. Elastic alpha-scattering of 112Sn and 124Sn at astrophysically relevant energies

    E-Print Network [OSTI]

    D. Galaviz; Zs. Fulop; Gy. Gyurky; Z. Mate; P. Mohr; T. Rauscher; E. Somorjai; A. Zilges

    2005-05-27

    The cross sections for the elastic scattering reactions {112,124}Sn(a,a){112,124}Sn at energies above and below the Coulomb barrier are presented and compared to predictions for global alpha-nucleus potentials. The high precision of the new data allows a study of the global alpha-nucleus potentials at both the proton and neutron-rich sides of an isotopic chain. In addition, local alpha-nucleus potentials have been extracted for both nuclei, and used to reproduce elastic scattering data at higher energies. Predictions from the capture cross section of the reaction 112Sn(a,g)116Te at astrophysically relevant energies are presented and compared to experimental data.

  1. Alpha-nucleus potential for alpha-decay and sub-barrier fusion

    E-Print Network [OSTI]

    V. Yu. Denisov; H. Ikezoe

    2005-10-27

    The set of parameters for alpha-nucleus potential is derived by using the data for both the alpha-decay half-lives and the fusion cross-sections around the barrier for reactions alpha+40Ca, alpha+59Co, alpha+208Pb. The alpha-decay half-lives are obtained in the framework of a cluster model using the WKB approximation. The evaluated alpha-decay half-lives and the fusion cross-sections agreed well with the data. Fusion reactions between alpha-particle and heavy nuclei can be used for both the formation of very heavy nuclei and spectroscopic studies of the formed compound nuclei.

  2. Aspartate beta-decarboxylase from Alcaligenes faecalis: carbon-13 kinetic isotope effect and deuterium exchange experiments

    SciTech Connect (OSTI)

    Rosenberg, R.M.; O'Leary, M.H.

    1985-03-26

    The authors have measured the /sup 13/C kinetic isotope effect at pH 4.0, 5.0, 6.0, and 6.5 and in D/sub 2/O at pH 5.0 and the rate of D-H exchange of the alpha and beta protons of aspartic acid in D/sub 2/O at pH 5.0 for the reaction catalyzed by the enzyme aspartate beta-decarboxylase from Alcaligenes faecalis. The /sup 13/C kinetic isotope effect, with a value of 1.0099 +/- 0.0002 at pH 5.0, is less than the intrinsic isotope effect for the decarboxylation step, indicating that the decarboxylation step is not entirely rate limiting. The authors have been able to estimate probable values of the relative free energies of the transition states of the enzymatic reaction up to and including the decarboxylation step from the /sup 13/C kinetic isotope effect and the rate of D-H exchange of alpha-H. The pH dependence of the kinetic isotope effect reflects the pKa of the pyridine nitrogen of the coenzyme pyridoxal 5'-phosphate but not that of the imine nitrogen. A mechanism is proposed for the exchange of aspartate beta-H that is consistent with the stereochemistry suggested earlier.

  3. RADIOCHEMICAL STUDIES OF NEUTRON DEFICIENT ACTINIDE ISOTOPES

    E-Print Network [OSTI]

    Williams, Kimberly Eve

    2011-01-01

    Isotope Targets and Foils, AERE-R 5097, Paper 10 (1965). V.Isotope Targets and Foils, AERE-R 5097 Paper 12 (1965). K.M.Isotope Targets and Foils, AERE-R-5097 Paper 11 (1965). M.

  4. X-Ray Synchrotron Emitting Fe-Rich Ejecta in SNR RCW 86

    E-Print Network [OSTI]

    Jeonghee Rho; Kristy K. Dyer; Kazimierz J. Borkowski; Stephen P. Reynolds

    2002-07-31

    Supernova remnants may exhibit both thermal and nonthermal X-ray emission. We present Chandra observations of RCW 86. Striking differences in the morphology of X-rays below 1 keV and above 2 keV point to a different physical origin. Hard X-ray emission is correlated fairly well with the edges of regions of radio emission, suggesting that these are the locations of shock waves at which both short-lived X-ray emitting electrons, and longer-lived radio-emitting electrons, are accelerated. Soft X-rays are spatially well-correlated with optical emission from nonradiative shocks, which are almost certainly portions of the outer blast wave. These soft X-rays are well fit with simple thermal plane-shock models. Harder X-rays show Fe K alpha emission and are well described with a similar soft thermal component, but a much stronger synchrotron continuum dominating above 2 keV, and a strong Fe K alpha line. Quantitative analysis of this line and the surrounding continuum shows that it cannot be produced by thermal emission from a cosmic-abundance plasma; the ionization time is too short, as shown both by the low centroid energy (6.4 keV) and the absence of oxygen lines below 1 keV. Instead, a model of a plane shock into Fe-rich ejecta, with a synchrotron continuum, provides a natural explanation. This requires that reverse shocks into ejecta be accelerating electrons to energies of order 50 TeV. We show that maximum energies of this order can be produced by radiation-limited diffusive shock acceleration at the reverse shocks.

  5. Advanced isotope separation

    SciTech Connect (OSTI)

    Not Available

    1982-05-04

    The Study Group briefly reviewed the technical status of the three Advanced Isotope Separation (AIS) processes. It also reviewed the evaluation work that has been carried out by DOE's Process Evaluation Board (PEB) and the Union Carbide Corporation-Nuclear Division (UCCND). The Study Group briefly reviewed a recent draft assessment made for DOE staff of the nonproliferation implications of the AIS technologies. The staff also very briefly summarized the status of GCEP and Advanced Centrifuge development. The Study Group concluded that: (1) there has not been sufficient progress to provide a firm scientific, technical or economic basis on which to select one of the three competing AIS processes for full-scale engineering development at this time; and (2) however, should budgetary restraints or other factors force such a selection, we believe that the evaluation process that is being carried out by the PEB provides the best basis available for making a decision. The Study Group recommended that: (1) any decisions on AIS processes should include a comparison with gas centrifuge processes, and should not be made independently from the plutonium isotope program; (2) in evaluating the various enrichment processes, all applicable costs (including R and D and sales overhead) and an appropriate discounting approach should be included in order to make comparisons on a private industry basis; (3) if the three AIS programs continue with limited resources, the work should be reoriented to focus only on the most pressing technical problems; and (4) if a decision is made to develop the Atomic Vapor Laser Isotope Separation process, the solid collector option should be pursued in parallel to alleviate the potential program impact of liquid collector thermal control problems.

  6. Alpha Gamma Hot Cell Facility

    E-Print Network [OSTI]

    Kemner, Ken

    . These operations can result in elevated radiological risks to the facility and workers. ARG-US -- meaning and should be developed for and deployed in nuclear and radiological facilities to aid operation and reduceAlpha Gamma Hot Cell Facility Argonne National Laboratory is a U.S. Department of Energy laboratory

  7. Isotopic Composition of Light Nuclei in Cosmic Rays: Results from AMS-01

    E-Print Network [OSTI]

    ,

    2011-01-01

    The variety of isotopes in cosmic rays allows us to study different aspects of the processes that cosmic rays undergo between the time they are produced and the time of their arrival in the heliosphere. In this paper we present measurements of the isotopic ratios 2H/4He, 3He/4He, 6Li/7Li, 7Be/(9Be+10Be) and 10B/11B in the range 0.2-1.4 GeV of kinetic energy per nucleon. The measurements are based on the data collected by the Alpha Magnetic Spectrometer, AMS-01, during the STS-91 flight in 1998 June.

  8. Isotopic Composition of Light Nuclei in Cosmic Rays: Results from AMS-01

    E-Print Network [OSTI]

    The AMS-01 Collaboration

    2011-06-12

    The variety of isotopes in cosmic rays allows us to study different aspects of the processes that cosmic rays undergo between the time they are produced and the time of their arrival in the heliosphere. In this paper we present measurements of the isotopic ratios 2H/4He, 3He/4He, 6Li/7Li, 7Be/(9Be+10Be) and 10B/11B in the range 0.2-1.4 GeV of kinetic energy per nucleon. The measurements are based on the data collected by the Alpha Magnetic Spectrometer, AMS-01, during the STS-91 flight in 1998 June.

  9. Effects of emitted electron temperature on the plasma sheath

    SciTech Connect (OSTI)

    Sheehan, J. P.; Kaganovich, I. D.; Wang, H.; Raitses, Y.; Sydorenko, D.; Hershkowitz, N.

    2014-06-15

    It has long been known that electron emission from a surface significantly affects the sheath surrounding that surface. Typical fluid theory of a planar sheath with emitted electrons assumes that the plasma electrons follow the Boltzmann relation and the emitted electrons are emitted with zero energy and predicts a potential drop of 1.03T{sub e}/e across the sheath in the floating condition. By considering the modified velocity distribution function caused by plasma electrons lost to the wall and the half-Maxwellian distribution of the emitted electrons, it is shown that ratio of plasma electron temperature to emitted electron temperature significantly affects the sheath potential when the plasma electron temperature is within an order of magnitude of the emitted electron temperature. When the plasma electron temperature equals the emitted electron temperature the emissive sheath potential goes to zero. One dimensional particle-in-cell simulations corroborate the predictions made by this theory. The effects of the addition of a monoenergetic electron beam to the Maxwellian plasma electrons were explored, showing that the emissive sheath potential is close to the beam energy only when the emitted electron flux is less than the beam flux.

  10. Saturn's emitted power Liming Li,1,2

    E-Print Network [OSTI]

    depends on precise measurements of the emitted thermal energy and the absorbed solar energy. We here energy and absorbed solar energy for a planet is generally called the energy balance [Conrath et al., 1989]. An internal heat source is inferred for the planet if the emitted thermal energy exceeds

  11. TRICOLOR LIGHT EMITTING DIODE DOT MATRIX DISPLAY SYSTEM WITHAUDIO OUTPUT

    E-Print Network [OSTI]

    Pang, Grantham

    1 TRICOLOR LIGHT EMITTING DIODE DOT MATRIX DISPLAY SYSTEM WITHAUDIO OUTPUT Grantham Pang, Chi emitting diodes; tricolor display; audio communication. I. Introduction This paper relates to a tricolor broadcasting through the visible light rays transmitted by the display panel or assembly. Keywords: light

  12. Indoor positioning algorithm using light-emitting diode visible light

    E-Print Network [OSTI]

    Kavehrad, Mohsen

    Indoor positioning algorithm using light- emitting diode visible light communications Zhou Zhou of Use: http://spiedl.org/terms #12;Indoor positioning algorithm using light-emitting diode visible light. This paper proposes a novel indoor positioning algorithm using visible light communications (VLC

  13. Photonic modes of organic light emitting Submitted by

    E-Print Network [OSTI]

    Exeter, University of

    is a metallic cathode. To achieve high efficiency OLEDs a primary issue to address is how the light resultingPhotonic modes of organic light emitting structures Submitted by Peter Allen Hobson for the award of a degree by this or any other University. #12;Abstract 2 Abstract Organic light emitting diodes

  14. The marine biogeochemistry of zinc isotopes

    E-Print Network [OSTI]

    John, Seth G

    2007-01-01

    Zinc (Zn) stable isotopes can record information about important oceanographic processes. This thesis presents data on Zn isotopes in anthropogenic materials, hydrothermal fluids and minerals, cultured marine phytoplankton, ...

  15. {gamma}-ray emitting radionuclide production in a multidimensional...

    Office of Scientific and Technical Information (OSTI)

    evolution and are further evolved with a 160 isotope network coupled to our PPM hydro code. Authors: Bazan, Grant 1 ; Arnett, David 2 + Show Author Affiliations...

  16. Efficient semiconductor light-emitting device and method

    DOE Patents [OSTI]

    Choquette, K.D.; Lear, K.L.; Schneider, R.P. Jr.

    1996-02-20

    A semiconductor light-emitting device and method are disclosed. The semiconductor light-emitting device is provided with at least one control layer or control region which includes an annular oxidized portion thereof to channel an injection current into the active region, and to provide a lateral refractive index profile for index guiding the light generated within the device. A periodic composition grading of at least one of the mirror stacks in the device provides a reduced operating voltage of the device. The semiconductor light-emitting device has a high efficiency for light generation, and may be formed either as a resonant-cavity light-emitting diode (RCLED) or as a vertical-cavity surface-emitting laser (VCSEL). 12 figs.

  17. Efficient semiconductor light-emitting device and method

    DOE Patents [OSTI]

    Choquette, Kent D. (Albuquerque, NM); Lear, Kevin L. (Albuquerque, NM); Schneider, Jr., Richard P. (Albuquerque, NM)

    1996-01-01

    A semiconductor light-emitting device and method. The semiconductor light-emitting device is provided with at least one control layer or control region which includes an annular oxidized portion thereof to channel an injection current into the active region, and to provide a lateral refractive index profile for index guiding the light generated within the device. A periodic composition grading of at least one of the mirror stacks in the device provides a reduced operating voltage of the device. The semiconductor light-emitting device has a high efficiency for light generation, and may be formed either as a resonant-cavity light-emitting diode (RCLED) or as a vertical-cavity surface-emitting laser (VCSEL).

  18. Isotope Research 229 Th production

    E-Print Network [OSTI]

    Isotope Research ­ 229 Th production We recently completed an ARRA-funded project of this type on 229 Th production reactions [Str11]. This long-lived isotope is important as a precursor to 225 Ac of accelerator production of 229 Th via the 230 Th(p,2n)229 Pa reaction. The 229 Pa decays primarily by electron

  19. Experimental Validation of the Multi-Isotope Process Monitor Concept

    SciTech Connect (OSTI)

    Orton, Christopher R.; Schwantes, Jon M.; Fraga, Carlos G.; Douglas, Matthew; Christensen, Richard

    2010-05-13

    Researchers from Pacific Northwest National Laboratory, in conjunction with personnel from The Ohio State University, are working to develop a system for monitoring spent nuclear fuel reprocessing facilities on-line, non-destructively, and in near-real-time. This method, known as the Multi-Isotope Process (MIP) Monitor, is based upon the measurement of distribution patterns of a suite of indicator (radioactive) isotopes present within particular process streams. Distribution patterns, monitored on-line by gamma spectrometry, are then compared in near-real-time to patterns representing "normal" process conditions using multivariate pattern recognition software. By targeting gamma-emitting indicator isotopes, the MIP Monitor approach is compatible with the use of small, portable, high-resolution gamma detectors that may be easily deployed throughout the facility. In addition, utilization of a suite of radio-elements, including ones with multiple oxidation states, increases the likelihood that attempts to divert material via process manipulation would be detected. Proof-of-principle modeling exercises simulating changes in acid strength have been completed and the results are promising. Laboratory validation is currently under way and significant results are available. The latest experimental results, along with an overview of the method will be presented.

  20. Organic Light-Emitting Diodes and Organic Light-emitting Electrochemical Cells Based on Silole-Fluorene Derivatives

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and to stop the well known spectral shift degradation occurring in fluorene based materials. In this paper we1 Organic Light-Emitting Diodes and Organic Light-emitting Electrochemical Cells Based on Silole-Fluorene, copolymerization of siloles with fluorene was aimed at improving electron injection into the polymer layer and so

  1. Supernova-Driven Outflows in NGC 7552: A Comparison of H-alpha and UV Tracers

    E-Print Network [OSTI]

    Wood, Corey M; Calzetti, Daniela; Leitherer, Claus; Chisholm, John; Gallagher, John S

    2015-01-01

    We investigate the supernova-driven galactic wind of the barred spiral galaxy NGC 7552, using both ground-based optical nebular emission lines and far-ultraviolet absorption lines measured with the Hubble Space Telescope Cosmic Origins Spectrograph. We detect broad (~300 km/s) blueshifted (-40 km/s) optical emission lines associated with the galaxy's kpc-scale star-forming ring. The broad line kinematics and diagnostic line ratios suggest that the H-alpha emission comes from clouds of high density gas entrained in a turbulent outflow. We compare the H-alpha emission line profile to the UV absorption line profile measured along a coincident sight line and find significant differences. The maximum blueshift of the H-alpha-emitting gas is ~290 km/s, whereas the UV line profile extends to blueshifts upwards of 1000 km/s. The mass outflow rate estimated from the UV is roughly nine times greater than that estimated from H-alpha. We argue that the H-alpha emission traces a cluster-scale outflow of dense, low velocit...

  2. Blue Wings and Bumps via Fermi-like Acceleration of Lyman-alpha photons across Shocks

    E-Print Network [OSTI]

    Chung, Andrew S; Ciardi, Benedetta; Gronke, Max

    2015-01-01

    We explore the impact of Fermi-like acceleration of Lyman-alpha (Ly{\\alpha}) photons across shock fronts on the observed Ly{\\alpha} spectral line shape. We first confirm the result of Neufeld & McKee (1988) that this mechanism gives rise to extended blue wings which may have been observed in some radio galaxies. Our Monte-Carlo radiative transfer calculations further show that in a minor modification of the shell-model, in which we add an additional static shell of hydrogen, this process can naturally explain the small blue bumps observed in a subset of Ly{\\alpha} emitting galaxies, which have been difficult to explain with conventional shell-models. Blue bumps can be produced with an additional column density of static hydrogen as small as $N_{HI}^{static} \\ll N_{HI}^{shell}$, and typically occur at roughly the outflow velocity of the shell. In our model the spectra of so-called 'blue-bump objects' might reflect an evolutionary stage in which the outflows regulating the escape of Ly{\\alpha} photons are s...

  3. Precision Test of Many-Body QED in the Be$^+$ $2p$ Fine Structure Doublet Using Short-Lived Isotopes

    E-Print Network [OSTI]

    Nörtershäuser, Wilfried; Krieger, Andreas; Pachucki, Krzysztof; Puchalski, Mariusz; Blaum, Klaus; Bissell, Mark L; Frömmgen, Nadja; Hammen, Michael; Kowalska, Magdalena; Krämer, Jörg; Kreim, Kim; Neugart, Rainer; Neyens, Gerda; Sánchez, Rodolfo; Yordanov, Deyan T

    2015-01-01

    Absolute transition frequencies of the $2s\\; ^2{\\rm S}_{1/2} \\rightarrow 2p\\;^2\\mathrm{P}_{1/2,3/2}$ transitions in Be$^+$ were measured for the isotopes $^{7,9-12}$Be. The fine structure splitting of the $2p$ state and its isotope dependence are extracted and compared to results of \\textit{ab initio} calculations using explicitly correlated basis functions, including relativistic and quantum electrodynamics effects at the order of $m \\alpha^6$ and $m \\alpha^7 \\ln \\alpha$. Accuracy has been improved in both the theory and experiment by 2 orders of magnitude, and good agreement is observed. This represents one of the most accurate tests of quantum electrodynamics for many-electron systems, being insensitive to nuclear uncertainties.

  4. Comparison of MCNP6 and experimental results for neutron counts, Rossi-{alpha}, and Feynman-{alpha} distributions

    SciTech Connect (OSTI)

    Talamo, A.; Gohar, Y.; Sadovich, S.; Kiyavitskaya, H.; Bournos, V.; Fokov, Y.; Routkovskaya, C.

    2013-07-01

    MCNP6, the general-purpose Monte Carlo N-Particle code, has the capability to perform time-dependent calculations by tracking the time interval between successive events of the neutron random walk. In fixed-source calculations for a subcritical assembly, the zero time value is assigned at the moment the neutron is emitted by the external neutron source. The PTRAC and F8 cards of MCNP allow to tally the time when a neutron is captured by {sup 3}He(n, p) reactions in the neutron detector. From this information, it is possible to build three different time distributions: neutron counts, Rossi-{alpha}, and Feynman-{alpha}. The neutron counts time distribution represents the number of neutrons captured as a function of time. The Rossi-a distribution represents the number of neutron pairs captured as a function of the time interval between two capture events. The Feynman-a distribution represents the variance-to-mean ratio, minus one, of the neutron counts array as a function of a fixed time interval. The MCNP6 results for these three time distributions have been compared with the experimental data of the YALINA Thermal facility and have been found to be in quite good agreement. (authors)

  5. Growths of staggered InGaN quantum wells light-emitting diodes emitting at 520525 nm employing graded growth-temperature profile

    E-Print Network [OSTI]

    Gilchrist, James F.

    Growths of staggered InGaN quantum wells light-emitting diodes emitting at 520­525 nm employing current spreading and light extraction in GaN-based light emitting diodes Appl. Phys. Lett. 100, 061107 (2012) Electrically driven nanopyramid green light emitting diode Appl. Phys. Lett. 100, 061106 (2012

  6. Laser separation of medical isotopes

    SciTech Connect (OSTI)

    Eerkens, J.W.; Puglishi, D.A.; Miller, W.H.

    1996-12-31

    There is an increasing demand for different separated isotopes as feed material for reactor and cyclotron-produced radioisotopes used by a fast-growing radiopharmaceutical industry. One new technology that may meet future demands for medical isotopes is molecular laser isotope separation (MLIS). This method was investigated for the enrichment of uranium in the 1970`s and 1980s by Los Alamos National Laboratory, Isotope Technologies, and others around the world. While South Africa and Japan have continued the development of MLIS for uranium and are testing pilot units, around 1985 the United States dropped the LANL MLIS program in favor of AVLIS (atomic vapor LIS), which uses electron-beam-heated uranium metal vapor. AVLIS appears difficult and expensive to apply to most isotopes of medical interest, however, whereas MLIS technology, which is based on cooled hexafluorides or other gaseous molecules, can be adapted more readily. The attraction of MLIS for radiopharmaceutical firms is that it allows them to operate their own dedicated separators for small-quantity productions of critical medical isotopes, rather than having to depend on large enrichment complexes run by governments, which are only optimal for large-quantity productions. At the University of Missouri, the authors are investigating LIS of molybdenum isotopes using MoF{sub 6}, which behaves in a way similar to UF{sub 6}, studied in the past.

  7. Kinetic deuterium isotope effects on deamination and N-hydroxylation of cyclohexylamine by rabbit liver microsomes

    SciTech Connect (OSTI)

    Kurebayashi, H.

    1989-04-01

    Deuterium isotope effects on the kinetic parameters for deamination and N-hydroxylation of cyclohexylamine (CHA) catalyzed by rabbit liver microsomes with NADPH are investigated. Both reactions are inhibited by carbon monoxide and have the characteristics of typical cytochrome P450-dependent monooxygenase reactions. A small and significant deuterium isotope effect operates in the oxidative deamination of CHA. The apparent isotope effects, i.e., VH/VD and (V/K)H/(V/K)D ratios for deamination, are 1.75 and 1.8-2.3, respectively. On the basis of N-hydroxylation, the VH/VD and (V/K)H/(V/K)D ratios are 0.8-0.9. The N-hydroxylation rate of alpha-deuterated CHA (D-CHA) is somewhat higher than that of CHA. The increased increment of hydroxylamine formation seems to coincide with the decreased amount of deamination. Substitution of deuterium in the alpha-position of CHA results in metabolic switching of cytochrome P450 from deamination to N-hydroxylation with low deuterium isotope effects. The data are interpreted in terms of an initial one-electron abstraction from the nitrogen to form an aminium cation radical followed by recombination with iron-bound hydroxyl radical leading to N-hydroxylamine, or followed by alpha-carbon deprotonation to form a neutral carbon radical. The latter can lead to a carbinolamine intermediate for deamination by way of amine or recombination with nascent iron-bound hydroxyl radical. The relative rates of the reactions depend on the alpha-carbon deprotonation rates of amines.

  8. Apparatus and process for separating hydrogen isotopes

    DOE Patents [OSTI]

    Heung, Leung K; Sessions, Henry T; Xiao, Xin

    2013-06-25

    The apparatus and process for separating hydrogen isotopes is provided using dual columns, each column having an opposite hydrogen isotopic effect such that when a hydrogen isotope mixture feedstock is cycled between the two respective columns, two different hydrogen isotopes are separated from the feedstock.

  9. Compelling Research Opportunities using Isotopes

    SciTech Connect (OSTI)

    2009-04-23

    Isotopes are vital to the science and technology base of the US economy. Isotopes, both stable and radioactive, are essential tools in the growing science, technology, engineering, and health enterprises of the 21st century. The scientific discoveries and associated advances made as a result of the availability of isotopes today span widely from medicine to biology, physics, chemistry, and a broad range of applications in environmental and material sciences. Isotope issues have become crucial aspects of homeland security. Isotopes are utilized in new resource development, in energy from bio-fuels, petrochemical and nuclear fuels, in drug discovery, health care therapies and diagnostics, in nutrition, in agriculture, and in many other areas. The development and production of isotope products unavailable or difficult to get commercially have been most recently the responsibility of the Department of Energy's Nuclear Energy program. The President's FY09 Budget request proposed the transfer of the Isotope Production program to the Department of Energy's Office of Science in Nuclear Physics and to rename it the National Isotope Production and Application program (NIPA). The transfer has now taken place with the signing of the 2009 appropriations bill. In preparation for this, the Nuclear Science Advisory Committee (NSAC) was requested to establish a standing subcommittee, the NSAC Isotope Subcommittee (NSACI), to advise the DOE Office of Nuclear Physics. The request came in the form of two charges: one, on setting research priorities in the short term for the most compelling opportunities from the vast array of disciplines that develop and use isotopes and two, on making a long term strategic plan for the NIPA program. This is the final report to address charge 1. NSACI membership is comprised of experts from the diverse research communities, industry, production, and homeland security. NSACI discussed research opportunities divided into three areas: (1) medicine, pharmaceuticals, and biology, (2) physical sciences and engineering, and (3) national security and other applications. In each area, compelling research opportunities were considered and the subcommittee as a whole determined the final priorities for research opportunities as the foundations for the recommendations. While it was challenging to prioritize across disciplines, our order of recommendations reflect the compelling research prioritization along with consideration of time urgency for action as well as various geopolitical market issues. Common observations to all areas of research include the needs for domestic availability of crucial stable and radioactive isotopes and the education of the skilled workforce that will develop new advances using isotopes in the future. The six recommendations of NSACI reflect these concerns and the compelling research opportunities for potential new discoveries. The science case for each of the recommendations is elaborated in the respective chapters.

  10. Raman scattering method and apparatus for measuring isotope ratios and isotopic abundances

    DOE Patents [OSTI]

    Harney, Robert C. (5665 Charlotte Way, No. 80, Livermore, CA 94550); Bloom, Stewart D. (141 Via Serena, Alamo, CA 94507)

    1978-01-01

    Raman scattering is used to measure isotope ratios and/or isotopic abundances. A beam of quasi-monochromatic photons is directed onto the sample to be analyzed, and the resulting Raman-scattered photons are detected and counted for each isotopic species of interest. These photon counts are treated mathematically to yield the desired isotope ratios or isotopic abundances.

  11. Development of ZnO Based Light Emitting Diodes and Laser Diodes

    E-Print Network [OSTI]

    Kong, Jieying

    2012-01-01

    E. Fred Schubert, Light-Emitting Diodes, New York (2006) [8]ZnO homojunction light emitting diode 3. 1. Motivation ofAlGaAs red light-emitting diodes, in: G.B. Stringfellow, M.

  12. Alpha

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O D S TA I N P A T TSorbentsAllosteric Modulation ofOeffect

  13. Identification of {gamma} rays from {sup 172}Au and {alpha} decays of {sup 172}Au, {sup 168}Ir, and {sup 164}Re

    SciTech Connect (OSTI)

    Hadinia, B.; Cederwall, B.; Andgren, K.; Baeck, T.; Johnson, A.; Khaplanov, A.; Wyss, R.; Page, R. D.; Grahn, T.; Paul, E. S.; Sandzelius, M.; Scholey, C.; Greenlees, P. T.; Jakobsson, U.; Jones, P. M.; Julin, R.; Juutinen, J.; Ketelhut, S.; Leino, M.; Nyman, M.

    2009-12-15

    The very neutron deficient odd-odd nucleus {sup 172}Au was studied in reactions of 342 and 348 MeV {sup 78}Kr beams with an isotopically enriched {sup 96}Ru target. The {alpha} decays previously reported for {sup 172}Au were confirmed and the decay chain extended down to {sup 152}Tm through the discovery of a new {alpha}-decaying state in {sup 164}Re[E{sub {alpha}}=5623(10) keV; t{sub 1/2}=864{sub -110}{sup +150} ms; b{sub {alpha}}=3(1)%]. Fine structure in these {alpha} decays of {sup 172}Au and {sup 168}Ir were identified. A new {alpha}-decaying state was also observed and assigned as the ground state in {sup 172}Au[E{sub {alpha}}=6762(10) keV; t{sub 1/2}=22{sub -5}{sup +6} ms]. This decay chain was also correlated down to {sup 152}Tm through previously reported {alpha} decays. Prompt {gamma} rays from excited states in {sup 172}Au have been identified using the recoil-decay tagging technique. The partial level scheme constructed for {sup 172}Au indicates that it has an irregular structure. Possible configurations of the {alpha}-decaying states in {sup 172}Au are discussed in terms of the systematics of nuclei in this region and total Routhian surface calculations.

  14. Thermoelectrically Pumped Light-Emitting Diodes Operating above Unity Efficiency

    E-Print Network [OSTI]

    Santhanam, Parthiban

    A heated semiconductor light-emitting diode at low forward bias voltage Velectrical work to pump heat from the lattice to the photon field. Here the rates of both radiative and nonradiative recombination ...

  15. Demonstration Assessment of Light-Emitting Diode (LED) Accent...

    Office of Scientific and Technical Information (OSTI)

    Accent Lighting at the Field Museum in Chicago, IL Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Accent Lighting at the Field...

  16. Demonstration Assessment of Light-Emitting Diode (LED) Parking...

    Office of Scientific and Technical Information (OSTI)

    Search Title: Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting at T.J.Maxx in Manchester, NH Phase I A report describing the process and results of...

  17. Improving the external extraction efficiency of organic light emitting devices

    E-Print Network [OSTI]

    Ho, John C., 1980-

    2004-01-01

    Over the last decade Organic Light Emitting Device (OLED) technology has matured, progressing to the point where state-of-the-art OLEDs can demonstrate external extraction efficiencies that surpass those of fluorescent ...

  18. Experimental detection of photons emitted during inhibited spontaneous emission

    E-Print Network [OSTI]

    Migdall, Alan

    Experimental detection of photons emitted during inhibited spontaneous emission David Branning of a "sudden mirror replacement" thought experiment, in which a mirror that is inhibiting spontaneous emission time prediction. Keywords: inhibited spontaneous emission, cavity QED, parametric downconversion

  19. Bright Light-Emitting Diodes based on Organometal Halide Perovskite

    E-Print Network [OSTI]

    Tan, Zhi-Kuang; Moghaddam, Reza Saberi; Lai, May Ling; Docampo, Pablo; Higler, Ruben; Deschler, Felix; Price, Michael; Sadhanala, Aditya; Pazos, Luis M.; Credgington, Dan; Hanusch, Fabian; Bein, Thomas; Snaith, Henry J.; Friend, Richard H.

    2014-08-03

    temperature and high vacuum processes, rendering them uneconomical for use in large area displays. Here, we report high brightness light-emitting diodes based on solution-processed organometal halide perovskites. We demonstrate electroluminescence in the near...

  20. Demonstration Assessment of Light-Emitting Diode Roadway Lighting...

    Office of Scientific and Technical Information (OSTI)

    New York Citation Details In-Document Search Title: Demonstration Assessment of Light-Emitting Diode Roadway Lighting on the FDR Drive in New York, New York This a report about a...

  1. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting

    SciTech Connect (OSTI)

    None

    2009-11-01

    A U.S. Department of Energy Solid-State Lighting Gateway Report on a Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting in Lija Loop, Portland, Oregon.

  2. White light emitting diode as liquid crystal display backlight

    E-Print Network [OSTI]

    Soon, Chian Myau

    2007-01-01

    The discovery of high brightness (white) light emitting diode (LED) is considered as a real threat to the current lighting industry in various applications. One of the most promising sectors would be using white LED to ...

  3. Wide band-gap nanowires for light emitting diodes

    E-Print Network [OSTI]

    Chesin, Jordan (Jordan Paul)

    2015-01-01

    Wide band-gap nanowires composed of GaN and ZnO are promising materials for unique designs and potential efficiency improvement of light emitting diodes (LEDs) for solid state lighting. The large surface-to-volume ratio ...

  4. White organic light-emitting diodes: Status and perspective

    E-Print Network [OSTI]

    Reineke, Sebastian

    White organic light-emitting diodes (OLEDs) are ultrathin, large-area light sources made from organic semiconductor materials. Over the past decades, much research has been spent on finding suitable materials to realize ...

  5. Novel hybrid isotope separation scheme and apparatus

    DOE Patents [OSTI]

    Maya, J.

    1991-06-18

    A method is described for yielding selectively a desired enrichment in a specific isotope including the steps of inputting into a spinning chamber a gas from which the specific isotope is to be isolated, radiating the gas with frequencies characteristic of the absorption of a particular isotope of the atomic or molecular gas, thereby inducing a photoionization reaction of the desired isotope, and collecting the specific isotope ion by suitable ion collection means. 3 figures.

  6. Physics with isotopically controlled semiconductors

    SciTech Connect (OSTI)

    Haller, E. E., E-mail: eehaller@lbl.gov [University of California at Berkeley, Department of Materials Science and Engineering (United States)

    2010-07-15

    This paper is based on a tutorial presentation at the International Conference on Defects in Semiconductors (ICDS-25) held in Saint Petersburg, Russia in July 2009. The tutorial focused on a review of recent research involving isotopically controlled semiconductors. Studies with isotopically enriched semiconductor structures experienced a dramatic expansion at the end of the Cold War when significant quantities of enriched isotopes of elements forming semiconductors became available for worldwide collaborations. Isotopes of an element differ in nuclear mass, may have different nuclear spins and undergo different nuclear reactions. Among the latter, the capture of thermal neutrons which can lead to neutron transmutation doping, is the most prominent effect for semiconductors. Experimental and theoretical research exploiting the differences in all the properties has been conducted and will be illustrated with selected examples.

  7. Alternative methods for degradation studies by alpha radiolysis: tributyl phosphate and CMPO

    SciTech Connect (OSTI)

    Pearson, J.; Nilsson, M. [University of California, Department of Chemical Engineering and Materials Science, 916 Engineering Tower, Irvine, CA 92697-2575 (United States); Miller, G.E. [University of California, Department of Chemistry, 1102 Natural Sciences 2, Irvine, CA 92697-2025 (United States)

    2013-07-01

    Solvent extraction separation processes used in the recycling of used nuclear fuel are susceptible to radiolytic damage from radioactive isotopes present in used fuel. Studying the respective effects on matter of both low linear energy transfer (LET) radiation such as gamma radiation and high LET such as alpha radiation will allow for accurate prediction and modeling of process performance losses with respect to dose. The effects of gamma radiation on solvent extraction ligands have been more extensively studied than the effects of alpha radiation due to the inherent difficulty in producing a sufficient and confluent dose of alpha particles within a sample without leaving the sample contaminated with long lived radioactive isotopes. We have developed a method for studying the effects of high LET radiation in situ via {sup 10}B activation and the high LET particles that result from the {sup 10}B(n,a){sup 7}Li reaction which follows. In this study we applied this method to organic solutions of tributyl phosphate (TBP) and CMPO (compound octylphenyl-N, N-diisobutyl-carbamoyl methyl phosphine oxide) representing the PUREX and TRUEX processes respectively. Rates of degradation of TBP and CMPO and their respective degradation products in the presence of both high and low LET radiation are presented and compared to values reported in the literature. Preliminary data appears to show decreased degradation of CMPO in the presence of an aqueous acidic phase, which agrees with other studies performed on TBP solutions. (authors)

  8. Organic light emitting device structure for obtaining chromaticity stability

    DOE Patents [OSTI]

    Tung, Yeh-Jiun (Princeton, NJ); Ngo, Tan (Levittown, PA)

    2007-05-01

    The present invention relates to organic light emitting devices (OLEDs). The devices of the present invention are efficient white or multicolored phosphorescent OLEDs which have a high color stability over a wide range of luminances. The devices of the present invention comprise an emissive region having at least two emissive layers, with each emissive layer comprising a different host and emissive dopant, wherein at least one of the emissive dopants emits by phosphorescence.

  9. High power light emitting diode based setup for photobleaching fluorescent impurities

    E-Print Network [OSTI]

    Kaufman, Laura

    High power light emitting diode based setup for photobleaching fluorescent impurities Tobias K be photobleached before final sample preparation. The instrument consists of high power light emitting diodes

  10. Modeling Population Exposures to Pollutants Emitted from Natural Gas Cooking Burners

    E-Print Network [OSTI]

    Lobscheid, Agnes

    2012-01-01

    BC et al. (2009). Natural Gas Variability in California:to Pollutants  Emitted from Natural Gas Cooking Burners  Pollutants Emitted from Natural Gas Cooking Burners Agnes B.

  11. Thermal Neutron Capture Cross Sections of the Palladium Isotopes

    E-Print Network [OSTI]

    2006-01-01

    CROSS SECTIONS OF THE PALLADIUM ISOTOPES R.B. Firestone ? ,? ? for all stable Palladium isotopes with the guidedscheme is complete. The Palladium isotope decay schemes are

  12. Isotope production facility produces cancer-fighting actinium

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

    Cancer therapy gets a boost from new isotope Isotope production facility produces cancer-fighting actinium A new medical isotope project shows promise for rapidly producing major...

  13. Local Varying-Alpha Theories

    E-Print Network [OSTI]

    John D. Barrow; Joao Magueijo

    2015-01-30

    In a recent paper we demonstrated how the simplest model for varying alpha may be interpreted as the effect of a dielectric material, generalized to be consistent with Lorentz invariance. Unlike normal dielectrics, such a medium cannot change the speed of light, and its dynamics obey a Klein-Gordon equation. This work immediately suggests an extension of the standard theory, even if we require compliance with Lorentz invariance. Instead of a wave equation, the dynamics may satisfy a local algebraic relation involving the permittivity and the properties of the electromagnetic field, in analogy with more conventional dielectric (but still preserving Lorentz invariance). We develop the formalism for such theories and investigate some phenomenological implications. The problem of the divergence of the classical self-energy can be solved, or at least softened, in this framework. Some interesting new cosmological solutions for the very early universe are found, including the possibility of a bounce, inflation and expansion with a loitering phase, all of which are induced by early variations in alpha.

  14. Beta/alpha continuous air monitor

    DOE Patents [OSTI]

    Becker, Gregory K. (Idaho Falls, ID); Martz, Dowell E. (Grand Junction, CO)

    1989-01-01

    A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinguishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts.

  15. Beta/alpha continuous air monitor

    DOE Patents [OSTI]

    Becker, G.K.; Martz, D.E.

    1988-06-27

    A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinquishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts. 7 figs.

  16. SU-E-J-03: A Comprehensive Comparison Between Alpha and Beta Emitters for Cancer Radioimmunotherapy

    SciTech Connect (OSTI)

    Huang, C.Y.; Guatelli, S; Oborn, B; Allen, B

    2014-06-01

    Purpose: The purpose of this study is to perform a comprehensive comparison of the therapeutic efficacy and cytotoxicity of alpha and beta emitters for Radioimmunotherapy (RIT). For each stage of cancer development, specific models were built for the separate objectives of RIT to be addressed:a) kill isolated cancer cells in transit in the lymphatic and vascular circulation,b) regress avascular cell clusters,c) regress tumor vasculature and tumors. Methods: Because of the nature of short range, high LET alpha and long energy beta radiation and heterogeneous antigen expression among cancer cells, the microdosimetric approach is essential for the RIT assessment. Geant4 based microdosimetric models are developed for the three different stages of cancer progression: cancer cells, cell clusters and tumors. The energy deposition, specific energy resulted from different source distribution in the three models was calculated separately for 4 alpha emitting radioisotopes ({sup 211}At, {sup 213}Bi, {sup 223}Ra and {sup 225}Ac) and 6 beta emitters ({sup 32}P, {sup 33}P, {sup 67}Cu, {sup 90}Y, {sup 131}I and {sup 177}Lu). The cell survival, therapeutic efficacy and cytotoxicity are determined and compared between alpha and beta emitters. Results: We show that internal targeted alpha radiation has advantages over beta radiation for killing isolated cancer cells, regressing small cell clusters and also solid tumors. Alpha particles have much higher dose specificity and potency than beta particles. They can deposit 3 logs more dose than beta emitters to single cells and solid tumor. Tumor control probability relies on deep penetration of radioisotopes to cancer cell clusters and solid tumors. Conclusion: The results of this study provide a quantitative understanding of the efficacy and cytotoxicity of RIT for each stage of cancer development.

  17. SHOE V.1.5 ALPHA

    Energy Science and Technology Software Center (OSTI)

    002913MLTPL00 Sandia Higher Order Elements (SHOE) v 0.5 alpha  http://midas3.kitware.com/midas/folder/10328 

  18. Improved repetition rate mixed isotope CO{sub 2} TEA laser

    SciTech Connect (OSTI)

    Cohn, D. B., E-mail: dbctechnology@earthlink.net [DBC Technology Corp., 4221 Mesa St, Torrance, California 90505 (United States)

    2014-09-15

    A compact CO{sub 2} TEA laser has been developed for remote chemical detection that operates at a repetition rate of 250 Hz. It emits 700 mJ/pulse at 10.6 ?m in a multimode beam with the {sup 12}C{sup 16}O{sub 2} isotope. With mixed {sup 12}C{sup 16}O{sub 2} plus {sup 13}C{sup 16}O{sub 2} isotopes it emits multiple lines in both isotope manifolds to improve detection of a broad range of chemicals. In particular, output pulse energies are 110?mJ/pulse at 9.77 ?m, 250 mJ/pulse at 10??m, and 550 mJ/pulse at 11.15??m, useful for detection of the chemical agents Sarin, Tabun, and VX. Related work shows capability for long term sealed operation with a catalyst and an agile tuner at a wavelength shift rate of 200 Hz.

  19. Optical Simulation of Top-emitting Organic Light Emitting Diodes H. J. Peng, C.F. Qiu, Z. L. Xie, H. Y. Chen, M. Wong and H. S. Kwok

    E-Print Network [OSTI]

    8.3.3-89 Optical Simulation of Top-emitting Organic Light Emitting Diodes H. J. Peng, C.F. Qiu, Z the optical effects for the top-emitting organic light emitting diodes. The optical performance of the devices with experiments Keywords: Top-emitting organic light emitting diode, optical modeling, microcavity INTRODUCTION

  20. alpha(s) Determinations from Jets and Scaling Violations at HERA

    E-Print Network [OSTI]

    Thomas Kluge

    2006-10-13

    A review is given on recent alpha(s) determinations from the H1 and ZEUS Collaborations. These are based on measurements of jet cross sections, event shape variables, as well as on the observed scaling violation of the structure function F_2. A HERA average on alpha(s)(m_Z) is presented, in comparison with world mean values.

  1. Standard guide for determination of plutonium and neptunium in uranium hexafluoride by alpha spectrometry

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This method covers the determination of plutonium and neptunium isotopes in uranium hexafluoride by alpha spectroscopy. The method can also be applicable to any matrix that may be converted to a nitric acid system. 1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory requirements prior to use.

  2. Evidence for an alpha cluster condensed state in 16O(alpha,alpha') at 400 MeV

    E-Print Network [OSTI]

    T. Wakasa; E. Ihara; K. Fujita; Y. Funaki; K. Hatanaka; H. Horiuchi; M. Itoh; J. Kamiya; G. Ropke; H. Sakaguchi; N. Sakamoto; Y. Sakemi; P. Schuck; Y. Shimizu; M. Takashina; S. Terashima; A. Tohsaki; M. Uchida; H. P. Yoshida; M. Yosoi

    2006-11-13

    Inelastic $\\alpha$ scattering on 16O is studied at 400 MeV by using an ice target. Near the 4-alpha breakup threshold of 14.4 MeV, a broad peak is observed at an excitation energy of 13.6+/-0.2 MeV with a width of 0.6+/-0.2 MeV. The spin-parity is estimated to be 0+ from the momentum-transfer dependence. The observed width is significantly larger than those of the neighboring 0+ states indicating a state with a well-developed alpha cluster structure. The magnitude of the cross section is sensitive to the density distribution of the constituent alpha clusters. The observed cross section is consistent with the theoretical prediction for the alpha cluster condensed state characterized by its dilute density distribution with a large root-mean-square radius of about 4.3 fm.

  3. High-alpha space trucks

    SciTech Connect (OSTI)

    Cook, L.M. [Ball Aerospace and Technology Corp. 1600 Commerce St. MS CO-9 Boulder, Colorado80301 (United States); Ball, J. [McDonnel Douglas Aerospace 5301 Bolsa Ave. MS 13-3 Huntington Beach, California92647 (United States)

    1997-01-01

    Vertically-landing Reusable Launch Vehicles (RLVs) are the best hope of building a true {open_quotes}Space Truck{close_quotes} with current technology. Because they do not require a low angle-of-attack (AOA, or alpha) horizontal landing, they can be designed to operate exclusively at very high angles-of-attack. This offers savings in vehicle dry weight and complexity, which can be traded for significantly heavier payload, more ascent velocity, or extra design margin. The price for abandoning low angle-of-attack flight is reduced crossrange. To quantify the potential weight reduction, a trade study was performed to determine the relationship between a vehicle{close_quote}s maximum crossrange (angle-of-attack) and it{close_quote}s dry weight (payload margin). At the study conclusion, three vertically-landing (VL) vehicles provided multiple points on a payload weight vs. maximum crossrange curve, showing significant payload increases as crossrange is sacrificed. This is primarily the result of being able to simplify the structure, fly a cooler entry trajectory, and be aerodynamically stable through the entire flight. This reduces subsystem requirements and complexity, enhancing reliability. Further benefits are realized in reduced landing propellant requirements and simplifying or eliminating the {open_quotes}rotation{close_quotes} maneuver. This paper also suggests unique operability solutions that adapt high-alpha vehicles to traditional high-crossrange missions such as the polar {open_quotes}once-around{close_quotes} flight, and proposes a small scale drop-test program to prove the subsonic and landing portion of the flight envelope. {copyright} {ital 1997 American Institute of Physics.}

  4. Isotope specific arbitrary material sorter

    DOE Patents [OSTI]

    Barty, Christopher P.J.

    2015-12-08

    A laser-based mono-energetic gamma-ray source is used to provide a rapid and unique, isotope specific method for sorting materials. The objects to be sorted are passed on a conveyor in front of a MEGa-ray beam which has been tuned to the nuclear resonance fluorescence transition of the desired material. As the material containing the desired isotope traverses the beam, a reduction in the transmitted MEGa-ray beam occurs. Alternately, the laser-based mono-energetic gamma-ray source is used to provide non-destructive and non-intrusive, quantitative determination of the absolute amount of a specific isotope contained within pipe as part of a moving fluid or quasi-fluid material stream.

  5. Flip-chip light emitting diode with resonant optical microcavity

    SciTech Connect (OSTI)

    Gee, James M.; Bogart, Katherine H.A.; Fischer, Arthur J.

    2005-11-29

    A flip-chip light emitting diode with enhanced efficiency. The device structure employs a microcavity structure in a flip-chip configuration. The microcavity enhances the light emission in vertical modes, which are readily extracted from the device. Most of the rest of the light is emitted into waveguided lateral modes. Flip-chip configuration is advantageous for light emitting diodes (LEDs) grown on dielectric substrates (e.g., gallium nitride LEDs grown on sapphire substrates) in general due to better thermal dissipation and lower series resistance. Flip-chip configuration is advantageous for microcavity LEDs in particular because (a) one of the reflectors is a high-reflectivity metal ohmic contact that is already part of the flip-chip configuration, and (b) current conduction is only required through a single distributed Bragg reflector. Some of the waveguided lateral modes can also be extracted with angled sidewalls used for the interdigitated contacts in the flip-chip configuration.

  6. Close-packed array of light emitting devices

    DOE Patents [OSTI]

    Ivanov, Ilia N.; Simpson, John T.

    2013-04-09

    A close-packed array of light emitting diodes includes a nonconductive substrate having a plurality of elongate channels extending therethrough from a first side to a second side, where each of the elongate channels in at least a portion of the substrate includes a conductive rod therein. The conductive rods have a density over the substrate of at least about 1,000 rods per square centimeter and include first conductive rods and second conductive rods. The close-packed array further includes a plurality of light emitting diodes on the first side of the substrate, where each light emitting diode is in physical contact with at least one first conductive rod and in electrical contact with at least one second conductive rod.

  7. Oxycarbonitride phosphors and light emitting devices using the same

    DOE Patents [OSTI]

    Li, Yuanqiang; Romanelli, Michael Dennis; Tian, Yongchi

    2013-10-08

    Disclosed herein is a novel family of oxycarbidonitride phosphor compositions and light emitting devices incorporating the same. Within the sextant system of M--Al--Si--O--N--C--Ln and quintuplet system of M--Si--O--N--C--Ln (M=alkaline earth element, Ln=rare earth element), the phosphors are composed of either one single crystalline phase or two crystalline phases with high chemical and thermal stability. In certain embodiments, the disclosed phosphor of silicon oxycarbidonitrides emits green light at wavelength between 530-550 nm. In further embodiments, the disclosed phosphor compositions emit blue-green to yellow light in a wavelength range of 450-650 nm under near-UV and blue light excitation.

  8. Light-emitting block copolymers composition, process and use

    DOE Patents [OSTI]

    Ferraris, John P.; Gutierrez, Jose J.

    2006-11-14

    Generally, and in one form, the present invention is a composition of light-emitting block copolymer. In another form, the present invention is a process producing a light-emitting block copolymers that intends polymerizing a first di(halo-methyl) aromatic monomer compound in the presence of an anionic initiator and a base to form a polymer and contacting a second di(halo-methyl) aromatic monomer compound with the polymer to form a homopolymer or block copolymer wherein the block copolymer is a diblock, triblock, or star polymer. In yet another form, the present invention is an electroluminescent device comprising a light-emitting block copolymer, wherein the electroluminescent device is to be used in the manufacturing of optical and electrical devices.

  9. Light emitting ceramic device and method for fabricating the same

    DOE Patents [OSTI]

    Valentine, Paul; Edwards, Doreen D.; Walker Jr., William John; Slack, Lyle H.; Brown, Wayne Douglas; Osborne, Cathy; Norton, Michael; Begley, Richard

    2004-11-30

    A light-emitting ceramic based panel, hereafter termed "electroceramescent" panel, and alternative methods of fabrication for the same are claimed. The electroceramescent panel is formed on a substrate providing mechanical support as well as serving as the base electrode for the device. One or more semiconductive ceramic layers directly overlay the substrate, and electrical conductivity and ionic diffusion are controlled. Light emitting regions overlay the semiconductive ceramic layers, and said regions consist sequentially of a layer of a ceramic insulation layer and an electroluminescent layer, comprised of doped phosphors or the equivalent. One or more conductive top electrode layers having optically transmissive areas overlay the light emitting regions, and a multi-layered top barrier cover comprising one or more optically transmissive non-combustible insulation layers overlay said top electrode regions.

  10. Oxycarbonitride phosphors and light emitting devices using the same

    DOE Patents [OSTI]

    Li, Yuanqiang; Romanelli, Michael Dennis; Tian, Yongchi

    2014-07-08

    Disclosed herein is a novel family of oxycarbonitride phosphor compositions and light emitting devices incorporating the same. Within the sextant system of M--Al--Si--O--N--C--Ln and quintuplet system of M--Si--O--N--C--Ln (M=alkaline earth element, Ln=rare earth element), the phosphors are composed of either one single crystalline phase or two crystalline phases with high chemical and thermal stability. In certain embodiments, the disclosed phosphor of silicon oxycarbonitrides emits green light at wavelength between 530-550 nm. In further embodiments, the disclosed phosphor compositions emit blue-green to yellow light in a wavelength range of 450-650 nm under near-UV and blue light excitation.

  11. Determination of alpha_s from the QCD static energy: an update

    E-Print Network [OSTI]

    Alexei Bazavov; Nora Brambilla; Xavier Garcia i Tormo; Peter Petreczky; Joan Soto; Antonio Vairo

    2014-11-04

    We present an update of our determination of the strong coupling alpha_s from the quantum chromodynamics static energy. This updated analysis includes new lattice data, at smaller lattice spacings and reaching shorter distances, the use of better suited perturbative expressions to compare with data in a wider distance range, and a comprehensive and detailed estimate of the error sources that contribute to the uncertainty of the final result. Our updated value for alpha_s at the Z-mass scale, M_Z, is alpha_s(M_Z)=0.1166^{+0.0012}_{-0.0008}, which supersedes our previous result.

  12. Online Catalog of Isotope Products from DOE's National Isotope Development Center

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The National Isotope Development Center (NIDC) interfaces with the User Community and manages the coordination of isotope production across the facilities and business operations involved in the production, sale, and distribution of isotopes. A virtual center, the NIDC is funded by the Isotope Development and Production for Research and Applications (IDPRA) subprogram of the Office of Nuclear Physics in the U.S. Department of Energy Office of Science. The Isotope subprogram supports the production, and the development of production techniques of radioactive and stable isotopes that are in short supply for research and applications. Isotopes are high-priority commodities of strategic importance for the Nation and are essential for energy, medical, and national security applications and for basic research; a goal of the program is to make critical isotopes more readily available to meet domestic U.S. needs. This subprogram is steward of the Isotope Production Facility (IPF) at Los Alamos National Laboratory (LANL), the Brookhaven Linear Isotope Producer (BLIP) facility at BNL, and hot cell facilities for processing isotopes at ORNL, BNL and LANL. The subprogram also coordinates and supports isotope production at a suite of university, national laboratory, and commercial accelerator and reactor facilities throughout the Nation to promote a reliable supply of domestic isotopes. The National Isotope Development Center (NIDC) at ORNL coordinates isotope production across the many facilities and manages the business operations of the sale and distribution of isotopes.

  13. Isotope Development & Production | Nuclear Science | ORNL

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

    Separation & Processing Strategic Isotope Production Super Heavy Element Discovery Nuclear Security Science & Technology Nuclear Systems Modeling, Simulation & Validation...

  14. Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression

    SciTech Connect (OSTI)

    Lochter, Andre; Navre, Marc; Werb, Zena; Bissell, Mina J

    1998-06-29

    Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits {alpha}6 and {beta}1, but not against {alpha}1 and {alpha}2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against {beta}1, but not against a6 or {alpha}2, interfered with cell adhesion to basement membrane constituents. Blocking antibodies against {alpha}1 integrins impaired only cell adhesion to type IV collagen. Antibodies against {alpha}1, {alpha}2, {alpha}6, and {beta}1, but not {alpha}5, integrin subunits reduced invasion of a reconstituted basement membrane. Integrins {alpha}1 and {alpha}2, which contributed only marginally to motility and adhesion, regulated proteinase production. Antibodies against {alpha}1 and {alpha}2, but not {alpha}6 and {beta}1, integrin subunits inhibited both transcription and protein expression of the matrix metalloproteinase stromelysin-1. Inhibition of tumor cell invasion by antibodies against {alpha}1 and {alpha}2 was reversed by addition of recombinant stromelysin-1. In contrast, stromelysin-1 could not rescue invasion inhibited by anti-{alpha}6 antibodies. Our data indicate that {alpha}1 and {alpha}2 integrins confer invasive behavior by regulating stromelysin-1 expression, whereas {alpha}6 integrins regulate cell motility. These results provide new insights into the specific functions of integrins during tumor cell invasion.

  15. Cluster structures in Oxygen isotopes

    E-Print Network [OSTI]

    N. Furutachi; M. kimura; A. Doté; Y. Kanada-En'yo; S. oryu

    2007-06-01

    Cluster structure of 16O,18O and 20O is investigated by the antisymmettrized molecular dynamics (AMD) plus generator coordinate method (GCM). We have found the K^{\\pi}=0$_2^+$ and 0$_1^-$ rotational bands of 18O that have the prominent 14C+\\alpha cluster structure. Clustering systematics becomes richer in 20O. We suggest the K^{\\pi}=0$_2^+$ band that is the mixture of the 12C+\\alpha+4n and 14C+6He cluster structures, and the K^{\\pi}=0$_1^-$ band that has the 14C+6He cluster structure. The K^{\\pi}=0$_3^+$ and 0$_2^-$ bands that have the prominent 16C+\\alpha cluster structure are also found.

  16. Isotope Cancer Treatment Research at LANL

    ScienceCinema (OSTI)

    Weidner, John; Nortier, Meiring

    2014-06-02

    Los Alamos National Laboratory has produced medical isotopes for diagnostic and imaging purposes for more than 30 years. Now LANL researchers have branched out into isotope cancer treatment studies. New results show that an accelerator-based approach can produce clinical trial quantities of actinium-225, an isotope that has promise as a way to kill tumors without damaging surrounding healthy cells.

  17. Lighting affects appearance LightSource emits photons

    E-Print Network [OSTI]

    Jacobs, David

    1 Lighting affects appearance #12;2 LightSource emits photons Photons travel in a straight line). And then some reach the eye/camera. #12;3 Basic fact: Light is linear Double intensity of sources, double photons reaching eye. Turn on two lights, and photons reaching eye are same as sum of number when each

  18. Lighting affects appearance LightSource emits photons

    E-Print Network [OSTI]

    Jacobs, David

    1 Lighting affects appearance #12;2 LightSource emits photons Photons travel in a straight line). And then some reach the eye/camera. #12;3 Reflectance Model how objects reflect light. Model light sources Algorithms for computing Shading: computing intensities within polygons Determine what light strikes what

  19. Actual Reflectometer on Fusion Experiment Emit radio frequency waves,

    E-Print Network [OSTI]

    Budny, Robert

    Actual Reflectometer on Fusion Experiment Emit radio frequency waves, measure reflected waves waves downloaded from URL. Added interactive graphics & visualization without changing existing Fortran 1019 1 keV 1 T Visualize Input Plasma Cross Sections Wave Reflection Layer (Cut-off Location) Compute

  20. Fabrication of High Efficiency, Printable Organic Light Emitting Diodes

    E-Print Network [OSTI]

    Petta, Jason

    design of OLED: Transparent Anode--ITO Glass substrate Organic layer(s) Metal Cathode Light #12;PRISMFabrication of High Efficiency, Printable Organic Light Emitting Diodes Michael AdamsMichael Adams: Design, fabricate, and characterize high efficiency OLEDs · Introduction · Background on OLEDs · Methods

  1. Calibrations of alpha Cen A & B

    E-Print Network [OSTI]

    Morel, P; Lebreton, Y; Thévenin, F; Berthomieu, G

    2000-01-01

    Detailed evolutionary models of the visual binary alpha Centauri, including pre main-sequence evolution, have been performed using the masses recently determined by Pourbaix et al. (1999). Models have been constructed using the CEFF equation of state, OPAL opacities, NACRE thermonuclear reaction rates and microscopic diffusion. A chi^2-minimization is performed to derive the most reliable set of modeling parameters wp={t_alpha Cen, Yi, [Fe/H]i, alpha A, alpha B}, where t alpha Cen is the age of the system, Yi the initial helium content, [Fe/H]i the initial metallicity and, alpha A and alpha B the convection parameters of the two components. Using the basic Bohm-Vitense (1958) mixing-length theory of convection, we derive wp BV={2710 Myr, 0.284,0.257, 1.53, 1.57}. We obtain a noticeably smaller age than estimated previously, in agreement with Pourbaix et al. (1999), mainly because of the larger masses. If convective core overshoot is considered we get wp ov={3530 Myr, 0.279,0.264,1.64,1.66}. The use of Canuto ...

  2. A single-particle/single-cell microbeam based on an isotopic alpha source

    E-Print Network [OSTI]

    . Randers-Pehrson, D.J. Brenner Columbia University, Radiological Research Accelerator Facility, 136 S-alone; Accelerator 1. Introduction and overall design Columbia UniversityÕs Radiological Research Accelerator Facility (RARAF) is home to a sin- gle-cell/single-particle microbeam based on a 4.2 MV Van de Graaff

  3. The Electric and Optical Properties of Doped Small Molecular Organic Light-Emitting Devices

    SciTech Connect (OSTI)

    Kwang-Ohk Cheon

    2003-08-05

    Organic light-emitting devices (OLEDs) constitute a new and exciting emissive display technology. In general, the basic OLED structure consists of a stack of fluorescent organic layers sandwiched between a transparent conducting-anode and metallic cathode. When an appropriate bias is applied to the device, holes are injected from the anode and electrons from the cathode; some of the recombination events between the holes and electrons result in electroluminescence (EL). Until now, most of the efforts in developing OLEDs have focused on display applications, hence on devices within the visible range. However some organic devices have been developed for ultraviolet or infrared emission. Various aspects of the device physics of doped small molecular OLEDs were described and discussed. The doping layer thickness and concentration were varied systematically to study their effects on device performances, energy transfer, and turn-off dynamics. Low-energy-gap DCM2 guest molecules, in either {alpha}-NPD or DPVBi host layers, are optically efficient fluorophores but also generate deep carrier trap-sites. Since their traps reduce the carrier mobility, the current density decreases with increased doping concentration. At the same time, due to efficient energy transfer, the quantum efficiency of the devices is improved by light doping or thin doping thickness, in comparison with the undoped neat devices. However, heavy doping induces concentration quenching effects. Thus, the doping concentration and doping thickness may be optimized for best performance.

  4. $\\alpha_s$ from the updated ALEPH data for hadronic $\\tau$ decays

    E-Print Network [OSTI]

    Boito, Diogo; Maltman, Kim; Osborne, James; Peris, Santiago

    2015-01-01

    We extract the strong coupling $\\alpha_s(m_\\tau^2)$ from the recently updated ALEPH non-strange spectral functions obtained from hadronic $\\tau$ decays. We apply a self-consistent analysis method, first tested in the analysis of OPAL data, to extract $\\alpha_s(m_\\tau^2)$ and non-perturbative contributions. The analysis yields $\\alpha_s^{\\rm FO}(m_\\tau^2)=0.296\\pm0.010 $, using Fixed Order Perturbation Theory (FOPT), and $\\alpha^{\\rm CI}_s(m_\\tau^2)= 0.310\\pm0.014$, using Contour Improved Perturbation Theory (CIPT). The weighted average of these results with those previously obtained from OPAL data give $\\alpha_s^{\\rm FO}(m_\\tau^2)=0.303\\pm 0.009$ and $\\alpha_s^{\\rm CI}(m_\\tau^2)=0.319\\pm 0.012$, which gives, after evolution to the $Z$ boson mass scale, $\\alpha^{\\rm FO}_s(m_Z^2)=0.1165\\pm0.0012 $ and $\\alpha_s^{\\rm CI}(m_Z^2)=0.1185\\pm0.0015 $, respectively. We observe that non-perturbative effects limit the accuracy with which $\\alpha_s$ can be extracted from $\\tau$ decay data.

  5. The Multi-Isotope Process (MIP) Monitor Project: FY13 Final Report

    SciTech Connect (OSTI)

    Meier, David E.; Coble, Jamie B.; Jordan, David V.; Mcdonald, Luther W.; Forrester, Joel B.; Schwantes, Jon M.; Unlu, Kenan; Landsberger, Sheldon; Bender, Sarah; Dayman, Kenneth J.; Reilly, Dallas D.

    2013-09-01

    The Multi-Isotope Process (MIP) Monitor provides an efficient approach to monitoring the process conditions in reprocessing facilities in support of the goal of “… (minimization of) the risks of nuclear proliferation and terrorism.” The MIP Monitor measures the distribution of the radioactive isotopes in product and waste streams of a nuclear reprocessing facility. These isotopes are monitored online by gamma spectrometry and compared, in near-real-time, to spectral patterns representing “normal” process conditions using multivariate analysis and pattern recognition algorithms. The combination of multivariate analysis and gamma spectroscopy allows us to detect small changes in the gamma spectrum, which may indicate changes in process conditions. By targeting multiple gamma-emitting indicator isotopes, the MIP Monitor approach is compatible with the use of small, portable, relatively high-resolution gamma detectors that may be easily deployed throughout an existing facility. The automated multivariate analysis can provide a level of data obscurity, giving a built-in information barrier to protect sensitive or proprietary operational data. Proof-of-concept simulations and experiments have been performed in previous years to demonstrate the validity of this tool in a laboratory setting for systems representing aqueous reprocessing facilities. However, pyroprocessing is emerging as an alternative to aqueous reprocessing techniques.

  6. Temporal stability of blue phosphorescent organic light-emitting diodes affected by thermal annealing of emitting layers

    E-Print Network [OSTI]

    Chen, Shaw H.

    Temporal stability of blue phosphorescent organic light-emitting diodes affected by thermal morphological instability as part of the challenge to the PhOLED device lifetime. Introduction Blue. In addition to the need for efficient and stable blue emitters,1,2 the technological advances in blue Ph

  7. NEW APPROACHES TO CONFINED ALPHA DIAGNOSTICS

    SciTech Connect (OSTI)

    FISHER,R.K

    2004-04-01

    Three new approaches to obtain information on the confined fast alphas in International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by {approx}140 microns per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER.

  8. Approaches to confined alpha diagnostics on ITER

    SciTech Connect (OSTI)

    Fisher, R.K. [General Atomics, PO Box 85608, San Diego, California 92186-5608 (United States)

    2004-10-01

    Three approaches to obtain information on the confined fast alphas in the International Thermonuclear Experimental Reactor (ITER) are proposed. The first technique measures the energetic charge exchange (CX) neutrals that result from the alpha collision-induced knock-on fuel ion tails undergoing electron capture on the MeV D neutral beams planned for heating and current drive. The second technique measures the energetic knock-on neutron tail due to alphas using the lengths of the proton recoil tracks produced by neutron collisions in nuclear emulsions. The range of the 14 to 20 MeV recoil protons increases by {approx}140 {mu}m per MeV. The third approach would measure the CX helium neutrals resulting from confined alphas capturing two electrons in the ablation cloud surrounding a dense gas jet that has been proposed for disruption mitigation in ITER.

  9. Nuclear diagnostic for fast alpha particles

    DOE Patents [OSTI]

    Grisham, L.R.; Post, D.E. Jr.; Dawson, J.M.

    1983-11-23

    This invention relates generally to high energy confined plasmas and more particularly is directed to measuring the velocity distribution of confined energetic alpha particles resulting from deuterium-tritium fusion reactions in a confined energetic plasma.

  10. Alpha particles in effective field theory

    SciTech Connect (OSTI)

    Caniu, C.

    2014-11-11

    Using an effective field theory for alpha (?) particles at non-relativistic energies, we calculate the strong scattering amplitude modified by Coulomb corrections for a system of two ?s. For the strong interaction, we consider a momentum-dependent interaction which, in contrast to an energy dependent interaction alone [1], could be more useful in extending the theory to systems with more than two ? particles. We will present preliminary results of our EFT calculations for systems with two alpha particles.

  11. Calibrations of alpha Cen A & B

    E-Print Network [OSTI]

    P. Morel; J. Provost; Y. Lebreton; F. Thevenin; G. Berthomieu

    2000-10-10

    Detailed evolutionary models of the visual binary alpha Centauri, including pre main-sequence evolution, have been performed using the masses recently determined by Pourbaix et al. (1999). Models have been constructed using the CEFF equation of state, OPAL opacities, NACRE thermonuclear reaction rates and microscopic diffusion. A chi^2-minimization is performed to derive the most reliable set of modeling parameters wp={t_alpha Cen, Yi, [Fe/H]i, alpha A, alpha B}, where t alpha Cen is the age of the system, Yi the initial helium content, [Fe/H]i the initial metallicity and, alpha A and alpha B the convection parameters of the two components. Using the basic Bohm-Vitense (1958) mixing-length theory of convection, we derive wp BV={2710 Myr, 0.284,0.257, 1.53, 1.57}. We obtain a noticeably smaller age than estimated previously, in agreement with Pourbaix et al. (1999), mainly because of the larger masses. If convective core overshoot is considered we get wp ov={3530 Myr, 0.279,0.264,1.64,1.66}. The use of Canuto & Mazitelli (1991, 1992) convection theory leads to the set wp CM={4086 Myr, 0.271, 0.264, 0.964, 0.986}. Using the observational constraints adopted by Guenther & Demarque (2000), and the basic mixing-length theory, we obtain wp GD={5640 Myr, 0.300, 0.296, 1.86, 1.97} and surface lithium depletions close to their observed values. A seismological analysis of our calibrated models has been performed. The determination of large and small spacings between the frequencies of acoustic oscillations from seismic observations would help to discriminate between the models of alpha Cen computed with different masses and to confirm or rules out the new determination of masses.

  12. Preparation and properties of (R)-(-)-1-azabicyclo(2. 2. 2)oct-3-yl- (R)-(+)-alpha-hydroxy-alpha-(4-( sup 125 I)iodophenyl)-alpha-phenyl acetate and (R)-(-)-1-azabicyclo(2. 2. 2)oct-3-yl-(S)-(-)-alpha-hydroxy-alpha- (4-( sup 125 I)iodophenyl)-alpha-phenyl acetate as potential radiopharmaceuticals

    SciTech Connect (OSTI)

    Cohen, V.I.; Rzeszotarski, W.J.; Gibson, R.E.; Fan, L.H.; Reba, R.C. )

    1989-10-01

    rac-4-Nitrobenzilic acid was synthesized and resolved with quinidine and quinine to give the corresponding (R)- and (S)-salts. The resolved diastereomeric salts were converted to (R)- and (S)-4-nitrobenzilic acids and subsequent esterification gave their corresponding ethyl esters. Transesterification with (R)-(-)-3-quinuclidinol afforded (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(R)-(+)-alpha-hydroxy-alpha- (4-nitrophenyl)-alpha-phenyl acetate and (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(S)-(-)-alpha-hydroxy- alpha-(4-nitrophenyl)-alpha-phenyl acetate. After hydrogenation, the (R,R)- and (R,S)-amines were converted to the respective triazene derivatives. The triazene derivatives reacted with sodium ({sup 125}I)iodide to give (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(R)-(+)- alpha-hydroxy-alpha-(4-({sup 125}I)iodophenyl)-alpha-phenyl acetate and (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(S)-(-)-alpha-hydroxy- alpha-(4-(125I)iodophenyl)-alpha-phenyl acetate. The evaluation of their affinities to muscarinic acetylcholine receptors (MAcChR) shows that (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(S)-(-)-alpha-hydroxy-alpha-(4- ({sup 125}I)iodophenyl)-alpha-phenyl acetate exhibits an affinity for the MAcChR from corpus striatum that is approximately threefold lower than that of (R)-(-)-1-azabicyclo(2.2.2)oct-3-yl-(R)-(+)-alpha-hydroxy-alpha-(4- ({sup 125}I)iodophenyl)-alpha-phenyl acetate.

  13. Benchmark of SCALE (SAS2H) isotopic predictions of depletion analyses for San Onofre PWR MOX fuel

    SciTech Connect (OSTI)

    Hermann, O.W.

    2000-02-01

    The isotopic composition of mixed-oxide (MOX) fuel, fabricated with both uranium and plutonium, after discharge from reactors is of significant interest to the Fissile Materials Disposition Program. The validation of the SCALE (SAS2H) depletion code for use in the prediction of isotopic compositions of MOX fuel, similar to previous validation studies on uranium-only fueled reactors, has corresponding significance. The EEI-Westinghouse Plutonium Recycle Demonstration Program examined the use of MOX fuel in the San Onofre PWR, Unit 1, during cycles 2 and 3. Isotopic analyses of the MOX spent fuel were conducted on 13 actinides and {sup 148}Nd by either mass or alpha spectrometry. Six fuel pellet samples were taken from four different fuel pins of an irradiated MOX assembly. The measured actinide inventories from those samples has been used to benchmark SAS2H for MOX fuel applications. The average percentage differences in the code results compared with the measurement were {minus}0.9% for {sup 235}U and 5.2% for {sup 239}Pu. The differences for most of the isotopes were significantly larger than in the cases for uranium-only fueled reactors. In general, comparisons of code results with alpha spectrometer data had extreme differences, although the differences in the calculations compared with mass spectrometer analyses were not extremely larger than that of uranium-only fueled reactors. This benchmark study should be useful in estimating uncertainties of inventory, criticality and dose calculations of MOX spent fuel.

  14. THE RGB AND AGB STAR NUCLEOSYNTHESIS IN LIGHT OF THE RECENT {sup 17}O(p, {alpha}){sup 14}N AND {sup 18}O(p, {alpha}){sup 15}N REACTION-RATE DETERMINATIONS

    SciTech Connect (OSTI)

    Palmerini, S.; Sergi, M. L.; La Cognata, M.; Pizzone, R. G.; Spitaleri, C. [INFN-Laboratori Nazionali del Sud, Catania (Italy)] [INFN-Laboratori Nazionali del Sud, Catania (Italy); Lamia, L. [Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy)] [Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy)

    2013-02-20

    In recent years, the Trojan Horse Method (THM) has been used to investigate the low-energy cross sections of proton-induced reactions on A = 17 and A = 18 oxygen isotopes, overcoming extrapolation procedures and enhancement effects due to electron screening. In particular, the strengths of the 20 keV and 65 keV resonances in the {sup 18}O(p, {alpha}){sup 15}N and {sup 17}O(p, {alpha}){sup 14}N reactions, respectively, have been extracted, as well as the contribution of the tail of the broad 656 keV resonance in the {sup 18}O(p, {alpha}){sup 15}N reaction inside the Gamow window. The strength of the 65 keV resonance in the {sup 17}O(p, {alpha}){sup 14}N reaction, measured by means of the THM, has been used to renormalize the corresponding resonance strength in the {sup 17}O + p radiative capture channel. As a result, more accurate reaction rates for the {sup 18}O(p, {alpha}){sup 15}N, {sup 17}O(p, {alpha}){sup 14}N, and {sup 17}O(p, {gamma}){sup 18}F processes have been deduced, devoid of systematic errors due to extrapolation or the electron screening effect. Such rates have been introduced into state-of-the-art red giant branch and asymptotic giant branch (AGB) models for proton-capture nucleosynthesis coupled with extra-mixing episodes. The predicted abundances have been compared with isotopic compositions provided by geochemical analysis of presolar grains. As a result, an improved agreement is found between the models and the isotopic mix of oxide grains of AGB origins, whose composition is the signature of low-temperature proton-capture nucleosynthesis. The low {sup 14}N/{sup 15}N found in SiC grains cannot be explained by the revised nuclear reaction rates and remains a serious problem that has not been satisfactorily addressed.

  15. Analysis of hydrogen isotope mixtures

    DOE Patents [OSTI]

    Villa-Aleman, Eliel (Aiken, SC)

    1994-01-01

    An apparatus and method for determining the concentrations of hydrogen isotopes in a sample. Hydrogen in the sample is separated from other elements using a filter selectively permeable to hydrogen. Then the hydrogen is condensed onto a cold finger or cryopump. The cold finger is rotated as pulsed laser energy vaporizes a portion of the condensed hydrogen, forming a packet of molecular hydrogen. The desorbed hydrogen is ionized and admitted into a mass spectrometer for analysis.

  16. Luminescence and Squeezing of a Superconducting Light Emitting Diode

    E-Print Network [OSTI]

    Hlobil, Patrik

    2015-01-01

    We investigate a semiconductor $p$-$n$ junction in contact with superconducting leads that is operated under forward bias as a light-emitting diode. The presence of superconductivity results in a significant increase of the electroluminescence in a certain frequency window. We demonstrate that the tunneling of Cooper pairs induces an additional luminescence peak on resonance. There is a transfer of superconducting to photonic coherence which results in the emission of entangled photon pairs and squeezing of the fluctuations in the quadrature amplitudes of the emitted light. The squeezing angle can be electrically manipulated by changing the relative phase of the order parameters in the superconductors. We finally derive the conditions for lasing in the system and show that the laser threshold is reduced due to superconductivity. This shows how macroscopic coherence of a superconductor can be used to control the properties of light.

  17. Organic light-emitting diodes from homoleptic square planar complexes

    SciTech Connect (OSTI)

    Omary, Mohammad A

    2013-11-12

    Homoleptic square planar complexes [M(N.LAMBDA.N).sub.2], wherein two identical N.LAMBDA.N bidentate anionic ligands are coordinated to the M(II) metal center, including bidentate square planar complexes of triazolates, possess optical and electrical properties that make them useful for a wide variety of optical and electrical devices and applications. In particular, the complexes are useful for obtaining white or monochromatic organic light-emitting diodes ("OLEDs"). Improved white organic light emitting diode ("WOLED") designs have improved efficacy and/or color stability at high brightness in single- or two-emitter white or monochrome OLEDs that utilize homoleptic square planar complexes, including bis[3,5-bis(2-pyridyl)-1,2,4-triazolato]platinum(II) ("Pt(ptp).sub.2").

  18. Luminescence and Squeezing of a Superconducting Light Emitting Diode

    E-Print Network [OSTI]

    Patrik Hlobil; Peter P. Orth

    2015-05-11

    We investigate a semiconductor $p$-$n$ junction in contact with superconducting leads that is operated under forward bias as a light-emitting diode. The presence of superconductivity results in a significant increase of the electroluminescence in a certain frequency window. We demonstrate that the tunneling of Cooper pairs induces an additional luminescence peak on resonance. There is a transfer of superconducting to photonic coherence which results in the emission of entangled photon pairs and squeezing of the fluctuations in the quadrature amplitudes of the emitted light. The squeezing angle can be electrically manipulated by changing the relative phase of the order parameters in the superconductors. We finally derive the conditions for lasing in the system and show that the laser threshold is reduced due to superconductivity. This shows how macroscopic coherence of a superconductor can be used to control the properties of light.

  19. High extraction efficiency ultraviolet light-emitting diode

    DOE Patents [OSTI]

    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.

  20. Phosphorescent organic light emitting diodes with high efficiency and brightness

    DOE Patents [OSTI]

    Forrest, Stephen R; Zhang, Yifan

    2015-11-12

    An organic light emitting device including a) an anode; b) a cathode; and c) an emissive layer disposed between the anode and the cathode, the emissive layer comprising an organic host compound and a phosphorescent compound exhibiting a Stokes Shift overlap greater than 0.3 eV. The organic light emitting device may further include a hole transport layer disposed between the emissive layer and the anode; and an electron transport layer disposed between the emissive layer and the cathode. In some embodiments, the phosphorescent compound exhibits a phosphorescent lifetime of less than 10 .mu.s. In some embodiments, the concentration of the phosphorescent compound ranges from 0.5 wt. % to 10 wt. %.

  1. Vertical-cavity surface-emitting laser device

    DOE Patents [OSTI]

    Hadley, G.R.; Lear, K.L.; Awyoung, A.; Choquette, K.D.

    1999-05-11

    A vertical-cavity surface-emitting laser device is disclosed. The vertical-cavity surface-emitting laser (VCSEL) device comprises one or more VCSELs with each VCSEL having a mode-control region thereabout, with the mode-control region forming an optical cavity with an effective cavity length different from the effective cavity length within each VCSEL. Embodiments of the present invention can be formed as single VCSELs and as one- or two-dimensional arrays of VCSELs, with either an index-guided mode of operation or an index anti-guided mode of operation being defined by a sign of the difference in the two effective cavity lengths. 10 figs.

  2. Concave-hemisphere-patterned organic top-light emitting device

    DOE Patents [OSTI]

    Forrest, Stephen R; Slootsky, Michael; Lunt, Richard

    2014-01-21

    A first device is provided. The first device includes an organic light emitting device, which further comprises a first electrode, a second electrode, and an organic emissive layer disposed between the first and second electrode. Preferably, the second electrode is more transparent than the first electrode. The organic emissive layer has a first portion shaped to form an indentation in the direction of the first electrode, and a second portion shaped to form a protrusion in the direction of the second electrode. The first device may include a plurality of organic light emitting devices. The indentation may have a shape that is formed from a partial sphere, a partial cylinder, a pyramid, or a pyramid with a mesa, among others. The protrusions may be formed between adjoining indentations or between an indentation and a surface parallel to the substrate.

  3. Wide Area Thermal Processing of Light Emitting Materials

    SciTech Connect (OSTI)

    Duty, Chad E; Joshi, Pooran C; Jellison Jr, Gerald Earle; Angelini, Joseph Attilio; Sabau, Adrian S

    2011-10-01

    Laboratory laser materials synthesis of wide bandgap materials has been successfully used to create white light emitting materials (LEMs). This technology development has progressed to the exploration on design and construction of apparatus for wide area doping and phase transformation of wide bandgap material substrates. The objective of this proposal is to develop concepts for wide area doping and phase transformation based on AppliCote Associates, LLC laser technology and ORNL high density pulsed plasma arc technology.

  4. Laterally injected light-emitting diode and laser diode

    DOE Patents [OSTI]

    Miller, Mary A.; Crawford, Mary H.; Allerman, Andrew A.

    2015-06-16

    A p-type superlattice is used to laterally inject holes into an III-nitride multiple quantum well active layer, enabling efficient light extraction from the active area. Laterally-injected light-emitting diodes and laser diodes can enable brighter, more efficient devices that impact a wide range of wavelengths and applications. For UV wavelengths, applications include fluorescence-based biological sensing, epoxy curing, and water purification. For visible devices, applications include solid state lighting and projection systems.

  5. Electrically injected visible vertical cavity surface emitting laser diodes

    DOE Patents [OSTI]

    Schneider, R.P.; Lott, J.A.

    1994-09-27

    Visible laser light output from an electrically injected vertical cavity surface emitting laser (VSCEL) diode is enabled by the addition of phase-matching spacer layers on either side of the active region to form the optical cavity. The spacer layers comprise InAlP which act as charge carrier confinement means. Distributed Bragg reflector layers are formed on either side of the optical cavity to act as mirrors. 5 figs.

  6. ISOTOPIC COMPOSITION OF LIGHT NUCLEI IN COSMIC RAYS: RESULTS FROM AMS-01

    SciTech Connect (OSTI)

    Aguilar, M.; Alcaraz, J.; Berdugo, J. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, E-28040 Madrid (Spain); Allaby, J. [European Laboratory for Particle Physics, CERN, CH-1211 Geneva 23 (Switzerland); Alpat, B.; Ambrosi, G.; Azzarello, P.; Battiston, R. [INFN-Sezione di Perugia, I-06100 Perugia (Italy); Anderhub, H. [Eidgenoessische Technische Hochschule, ETH Zuerich, CH-8093 Zuerich (Switzerland); Ao, L. [Chinese Academy of Launching Vehicle Technology, CALT, 100076 Beijing (China); Arefiev, A. [Institute of Theoretical and Experimental Physics, ITEP, Moscow 117259 (Russian Federation); Arruda, L.; Barao, F.; Barreira, G. [Laboratorio de Instrumentacao e Fisica Experimental de Particulas, LIP, P-1000 Lisboa (Portugal); Basile, M.; Bellagamba, L. [Dipartimento di Fisica and INFN, Universita di Bologna, I-40126 Bologna (Italy); Bartoloni, A. [INFN-Sezione di Roma, I-00185 Roma (Italy); Becker, R.; Becker, U.; Berges, P., E-mail: Nicola.Tomassetti@pg.infn.it [Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2011-08-01

    The variety of isotopes in cosmic rays allows us to study different aspects of the processes that cosmic rays undergo between the time they are produced and the time of their arrival in the heliosphere. In this paper, we present measurements of the isotopic ratios {sup 2}H/{sup 4}He, {sup 3}He/{sup 4}He, {sup 6}Li/{sup 7}Li, {sup 7}Be/({sup 9}Be+{sup 10}Be), and {sup 10}B/{sup 11}B in the range 0.2-1.4 GeV of kinetic energy per nucleon. The measurements are based on the data collected by the Alpha Magnetic Spectrometer, AMS-01, during the STS-91 flight in 1998 June.

  7. Carbon Isotopic Studies of Assimilated and Ecosystem Respired CO2 in a Southeastern Pine Forest. Final Report and Conference Proceedings

    SciTech Connect (OSTI)

    Conte, Maureen H

    2008-04-10

    Carbon dioxide is the major “greenhouse” gas responsible for global warming. Southeastern pine forests appear to be among the largest terrestrial sinks of carbon dioxide in the US. This collaborative study specifically addressed the isotopic signatures of the large fluxes of carbon taken up by photosynthesis and given off by respiration in this ecosystem. By measuring these isotopic signatures at the ecosystem level, we have provided data that will help to more accurately quantify the magnitude of carbon fluxes on the regional scale and how these fluxes vary in response to climatic parameters such as rainfall and air temperature. The focus of the MBL subcontract was to evaluate how processes operating at the physiological and ecosystem scales affects the resultant isotopic signature of plant waxes that are emitted as aerosols into the convective boundary layer. These wax aerosols provide a large-spatial scale integrative signal of isotopic discrimination of atmospheric carbon dioxide by terrestrial photosynthesis (Conte and Weber 2002). The ecosystem studies have greatly expanded of knowledge of wax biosynthetic controls on their isootpic signature The wax aerosol data products produced under this grant are directly applicable as input for global carbon modeling studies that use variations in the concentration and carbon isotopic composition of atmospheric carbon dioxide to quantify the magnitude and spatial and temporal patterns of carbon uptake on the global scale.

  8. Green exciplex emission from a bilayer light-emitting diode containing a rare earth ternary complex

    E-Print Network [OSTI]

    Huang, Yanyi

    Green exciplex emission from a bilayer light-emitting diode containing a rare earth ternary complex form 18 October 2001 Abstract A bilayer organic light-emitting diode using a blue-fluorescent yttrium

  9. Multispectral imaging of the ocular fundus using light emitting diode illumination

    E-Print Network [OSTI]

    Claridge, Ela

    Multispectral imaging of the ocular fundus using light emitting diode illumination N. L. Everdell,1 on light emitting diode LED illumination that produces multispectral optical images of the human ocular

  10. Materials and architectures for efficient harvesting of singlet and triplet excitons for white light emitting OLEDs

    DOE Patents [OSTI]

    Thompson, Mark E; Forrest, Stephen

    2015-02-03

    The present invention relates to organic light emitting devices (OLEDs), and more specifically to OLEDS that emit light using a combination of fluorescent emitters and phosphorescent emitters for the efficient utilization of all of the electrically generated excitons.

  11. Phase-locked arrays of surface-emitting terahertz quantum-cascade lasers

    E-Print Network [OSTI]

    Kao, Tsung-Yu

    We report the demonstration of phase-locked arrays of surface-emitting distributed-feedback (DFB) terahertz quantum-cascade lasers with single-mode operations. Carefully designed “phase sector” locks several surface-emitting ...

  12. Injection and transport processes in organic light emitting diodes based on N. Huby a,b

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Injection and transport processes in organic light emitting diodes based on a silole. N. Huby a- conductors in light emitting diodes1 . The different fields of research around the organic electronic allowed

  13. Light extraction enhanced white light-emitting diodes with multi-layered phosphor configuration

    E-Print Network [OSTI]

    You, Jiun Pyng; Tran, Nguyen T.; Shi, Frank G.

    2010-01-01

    and J. K. Kim, “Solid-state light sources getting smart,”power phosphor-converted light-emitting diodes based on III-for phosphor- based white-light-emitting diodes,” Appl.

  14. Efficient Light-Emitting Diodes Based on Nanocrystalline Perovskite in a Dielectric Polymer Matrix

    E-Print Network [OSTI]

    Li, Guangru; Tan, Zhi-Kuang; Di, Dawei; Lai, May Ling; Jiang, Lang; Lim, Jonathan Hua-Wei; Friend, Richard H.; Greenham, Neil C.

    2015-02-24

    Electroluminescence in light-emitting devices relies on the encounter and radiative recombination of electrons and holes in the emissive layer. In organometal halide perovskite light-emitting diodes, poor film formation creates electrical shunting...

  15. Observable form of pulses emitted from relativistic collapsing objects

    SciTech Connect (OSTI)

    Frolov, Valeri P.; Lee, Hyun Kyu

    2005-02-15

    In this work, we discuss observable characteristics of the radiation emitted from a surface of a collapsing object. We study a simplified model in which a radiation of massless particles has a sharp in time profile, and it happens at the surface at the same moment of comoving time. Since the radiating surface has finite size the observed radiation will occur during some finite time. Its redshift and bending angle are affected by the strong gravitational field. We obtain a simple expression for the observed flux of the radiation as a function of time. To find an explicit expression for the flux we develop an analytical approximation for the bending angle and time delay for null rays emitted by a collapsing surface. In the case of the bending angle this approximation is an improved version of the earlier proposed Beloborodov-Leahy-approximation. For rays emitted at R>2R{sub g} the accuracy of the proposed improved approximations for the bending angle and time delay is of order (or less) than 2%-3%. By using this approximation we obtain an approximate analytical expression for the observed flux and study its properties.

  16. Observable Form of Pulses Emitted From Relativistic Collapsing Objects

    SciTech Connect (OSTI)

    Frolov, V.

    2005-01-28

    In this work, we discuss observable characteristics of the radiation emitted from a surface of a collapsing object. We study a simplified model in which a radiation of massless particles has a sharp in time profile and it happens at the surface at the same moment of comoving time. Since the radiating surface has finite size the observed radiation will occur during some finite time. Its redshift and bending angle are affected by the strong gravitational field. We obtain a simple expression for the observed flux of the radiation as a function of time. To find an explicit expression for the flux we develop an analytical approximation for the bending angle and time delay for null rays emitted by a collapsing surface. In the case of the bending angle this approximation is an improved version of the earlier proposed Beloborodov-Leahy-approximation. For rays emitted at R > 2R{sub g} the accuracy of the proposed improved approximations for the bending angle and time delay is of order (or less) than 2-3%. By using this approximation we obtain an approximate analytical expression for the observed flux and study its properties.

  17. The Spin-Kinetic Temperature Coupling and the Heating Rate due to Lyman Alpha Scattering before Reionization: Predictions for 21cm Emission and Absorption

    E-Print Network [OSTI]

    Xuelei Chen; Jordi Miralda-Escude

    2003-07-25

    We investigate the interaction of Lyman alpha photons produced by the first stars in the universe with the intergalactic medium (IGM) prior to reionization. The background Lyman alpha spectral profile is obtained by solving a Fokker-Planck equation. Accurate values of the heating and scattering rates, and the spin-kinetic temperature coupling coefficient, are presented. We show that the heating rate induced by the Lyman alpha scatterings is much lower than found previously, and is basically negligible. The dominant heating source is most likely the X-rays from the first ionizing sources, which are able to penetrate into the atomic medium. The scattering of Lyman alpha photons couples the hydrogen spin temperature to the kinetic temperature. If the first ionizing sources in the universe did not emit significant X-rays, the spin temperature would be rapidly brought down to the very low gas kinetic temperature, and a 21cm absorption signal against the CMB larger than 100 mK would be predicted. However, we argue that sufficient X-rays are likely to have been emitted by the first stellar population, implying that the gas kinetic temperature should rapidly increase, turning a reduced and brief absorption signal into emission, with a smaller amplitude of about 10 mK. The detection of the 21cm absorption and emission feature would be a hallmark in unravelling the history of the ``dark age'' before reionization.

  18. Process development for the fabrication of light emitting vacuum field emission triodes 

    E-Print Network [OSTI]

    Williams, Roger T.

    1994-01-01

    . Light emitting diodes and triodes are also fabricated to address the feasibility of their application to flat panel displays....

  19. Stable Isotope Enrichment Capabilities at ORNL

    SciTech Connect (OSTI)

    Egle, Brian; Aaron, W Scott; Hart, Kevin J

    2013-01-01

    The Oak Ridge National Laboratory (ORNL) and the US Department of Energy Nuclear Physics Program have built a high-resolution Electromagnetic Isotope Separator (EMIS) as a prototype for reestablishing a US based enrichment capability for stable isotopes. ORNL has over 60 years of experience providing enriched stable isotopes and related technical services to the international accelerator target community, as well as medical, research, industrial, national security, and other communities. ORNL is investigating the combined use of electromagnetic and gas centrifuge isotope separation technologies to provide research quantities (milligram to several kilograms) of enriched stable isotopes. In preparation for implementing a larger scale production facility, a 10 mA high-resolution EMIS prototype has been built and tested. Initial testing of the device has simultaneously collected greater than 98% enriched samples of all the molybdenum isotopes from natural abundance feedstock.

  20. Isotopic mass separation with the RICH detector of the AMS Experiment

    E-Print Network [OSTI]

    Arruda, Luísa; Borges, João; Gonçalves, Patrícia; Pereira, Rui; Pimenta, Mário; Carmo, Fernando

    2008-01-01

    The Alpha Magnetic Spectrometer (AMS) to be installed on the International Space Station (ISS) will be equipped with a proximity focusing Ring Imaging Cerenkov detector (RICH). Reconstruction of the Cerenkov angle and the electric charge with RICH are discussed. A likelihood method for the Cerenkov angle reconstruction was applied leading to a velocity determination for protons with a resolution around 0.1%. The electric charge reconstruction is based on the counting of the number of photoelectrons and on an overall efficiency estimation on an event-by-event basis. The isotopic mass separation of helium and beryllium is presented.

  1. Isotopic mass separation with the RICH detector of the AMS Experiment

    E-Print Network [OSTI]

    Luísa Arruda; Fernando Barão; João Borges; Patrícia Gonçalves; Rui Pereira; Mário Pimenta; Fernando Carmo

    2008-01-30

    The Alpha Magnetic Spectrometer (AMS) to be installed on the International Space Station (ISS) will be equipped with a proximity focusing Ring Imaging Cerenkov detector (RICH). Reconstruction of the Cerenkov angle and the electric charge with RICH are discussed. A likelihood method for the Cerenkov angle reconstruction was applied leading to a velocity determination for protons with a resolution around 0.1%. The electric charge reconstruction is based on the counting of the number of photoelectrons and on an overall efficiency estimation on an event-by-event basis. The isotopic mass separation of helium and beryllium is presented.

  2. Highly efficient inverted top emitting organic light emitting diodes using a transparent top electrode with color stability on viewing angle

    SciTech Connect (OSTI)

    Kim, Jung-Bum; Lee, Jeong-Hwan; Moon, Chang-Ki; Kim, Jang-Joo, E-mail: jjkim@snu.ac.kr [Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2014-02-17

    We report a highly efficient phosphorescent green inverted top emitting organic light emitting diode with excellent color stability by using the 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile/indium zinc oxide top electrode and bis(2-phenylpyridine)iridium(III) acetylacetonate as the emitter in an exciplex forming co-host system. The device shows a high external quantum efficiency of 23.4% at 1000?cd/m{sup 2} corresponding to a current efficiency of 110?cd/A, low efficiency roll-off with 21% at 10?000?cd/m{sup 2} and low turn on voltage of 2.4?V. Especially, the device showed very small color change with the variation of ?x?=?0.02, ?y?=?0.02 in the CIE 1931 coordinates as the viewing angle changes from 0° to 60°. The performance of the device is superior to that of the metal/metal cavity structured device.

  3. Piper Alpha and Independence Marion King Hubbert (1903 1989) Piper Alpha (6 July 1988)

    E-Print Network [OSTI]

    be a second Piper Alpha tragedy for Scotland if its historical effect on oil production has not been by the Yes campaign. Following Piper Alpha, oil production was deliberately cut back in order to allow assessment of Scotland's likely remaining oil wealth (including new finds). The Hubbert production forecast

  4. R(s) and hadronic tau-Decays in Order alpha_s^4: technical aspects

    E-Print Network [OSTI]

    P. A. Baikov; K. G. Chetyrkin; J. H. Kühn

    2009-06-16

    We report on some technical aspects of our calculation of alpha_s^4 corrections to R(s) and the semi-leptonic tau decay width [1-3]. We discuss the inner structure of the result as well as the issue of its correctness. We demonstrate recently appeared independent evidence positively testing one of two components of the full result.

  5. Efficient blue organic light-emitting diodes employing thermally activated delayed

    E-Print Network [OSTI]

    Cai, Long

    Efficient blue organic light-emitting diodes employing thermally activated delayed fluorescence,2 * Organic light-emitting diodes (OLEDs) employing thermally activated delayed fluorescence (TADF) have energy is high enough and the 3 LE state is higher than the 3 CT state. O rganic light-emitting diodes

  6. A description and evaluation of light-emitting diode displays for generation of visual stimuli*

    E-Print Network [OSTI]

    Massaro, Dominic

    A description and evaluation of light-emitting diode displays for generation of visual stimuli 53706 A description of the design and function of light-emitting diode (LED) display modules is given (Time, April 1972). Light-emitting diodes (L~Ds) are examples of these spin-offs, LED display devices

  7. Correlation between the Indium Tin Oxide morphology and the performances of polymer light-emitting diodes

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    : This paper reports on performance enhancement of polymer light-emitting diodes (PLEDs) based on poly(2,5-bis. Keywords : Polymer light emitting diode; Indium tin oxide; Atomic force microscopy; Rutherford backscattering spectroscopy 1. Introduction Polymer light-emitting diodes (PLEDs) have received worldwide

  8. High efficiency light emitting diode with anisotropically etched GaN-sapphire interface

    E-Print Network [OSTI]

    High efficiency light emitting diode with anisotropically etched GaN- sapphire interface M. H. Lo and optimization of a light-emitting diode projection micro-stereolithography three-dimensional manufacturingGaN micro-light emitting diodes Appl. Phys. Lett. 101, 231110 (2012) A bright cadmium-free, hybrid organic

  9. spectroscopic techniques A Multi-Source Portable Light Emitting Diode Spectrofluorometer

    E-Print Network [OSTI]

    spectroscopic techniques A Multi-Source Portable Light Emitting Diode Spectrofluorometer SAFWAN only 1.5 kg that uses multiple light emitting diodes (LEDs) as excitation sources was developed emitting diodes; LEDs; Animal forage; Excitation-emission matrices; EEM. INTRODUCTION Movement of chemical

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

    E-Print Network [OSTI]

    Ashworth, Stephen H.

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

  11. Poly(p-phenylene vinylene)/tris(8-hydroxy) quinoline aluminum heterostructure light emitting diode

    E-Print Network [OSTI]

    Poly(p-phenylene vinylene)/tris(8-hydroxy) quinoline aluminum heterostructure light emitting diode are presented from polymer/molecular organic heterostructure light emitting diodes composed of a layer,2 organic light emitting diodes OLEDs utilizing fluorescent molecules have attracted considerable interest

  12. Point defect engineered Si sub-bandgap light-emitting diode

    E-Print Network [OSTI]

    Bao, Jiming

    Point defect engineered Si sub-bandgap light-emitting diode Jiming Bao1 , Malek Tabbal1,2 , Taegon light emission in Si and demonstrate a sub-bandgap light emitting diode based on the introduction OCIS codes: (230.3670) Light-emitting diodes; (160.6000) Semiconductors; (130-0250) Optoelectronics

  13. Enhancement of Barrier Properties Using Ultrathin Hybrid Passivation Layer for Organic Light Emitting Diodes

    E-Print Network [OSTI]

    Hwang, Sung Woo

    acrylate layer and MS-31 (MgO : SiO2 ¼ 3 : 1 wt %) layer was adopted in organic light emitting diode (OLED the penetrations of oxygen and moisture. [DOI: 10.1143/JJAP.45.5970] KEYWORDS: organic light emitting diode (OLED. Introduction As a next generation display, the organic light emitting diode (OLED) has to great performances

  14. Room temperature 1.6 m electroluminescence from Ge light emitting diode on Si substrate

    E-Print Network [OSTI]

    Vuckovic, Jelena

    Room temperature 1.6 µm electroluminescence from Ge light emitting diode on Si substrate Szu n+/p light emitting diode on a Si substrate. Unlike normal electrically pumped devices, this device.4670) Optical materials; (230.3670) Light-emitting diodes. References and links 1. L. C. Kimerling, "Silicon

  15. Color-tunable light emitting diodes based on quantum dot suspension

    E-Print Network [OSTI]

    Wu, Shin-Tson

    Color-tunable light emitting diodes based on quantum dot suspension Zhenyue Luo, Haiwei Chen, Yifan March 2015 We propose a color-tunable light emitting diode (LED) consisting of a blue LED as the light, rendering and metamerism; (230.3670) Light-emitting diodes. http://dx.doi.org/10.1364/AO.54.002845 1

  16. Enhanced coupling of light from organic light emitting diodes using nanoporous films

    E-Print Network [OSTI]

    Enhanced coupling of light from organic light emitting diodes using nanoporous films H. J. Peng, Y the light extraction efficiency for organic light emitting diode OLED . Nanoporous alumina film was used by Bragg scattering. The corrugated light- emitting diode had two-times the efficiency as compared

  17. Light extraction analysis and enhancement in a quantum dot light emitting diode

    E-Print Network [OSTI]

    Wu, Shin-Tson

    Light extraction analysis and enhancement in a quantum dot light emitting diode Ruidong Zhu outcoupling and angular performance of quantum dot light emitting diode (QLED). To illustrate the design principles, we use a red QLED as an example and compare its performance with an organic light emitting diode

  18. Space charge spectroscopy of integrated quantum well infrared photodetectorlight emitting diode

    E-Print Network [OSTI]

    Perera, A. G. Unil

    Space charge spectroscopy of integrated quantum well infrared photodetector±light emitting diode M ± light emitting diode (QWIP-LED). Quasistatic capacitance±voltage (C±V ) characteristics under reverse.V. All rights reserved. Keywords: Quantum-well infrared photodetector; Light-emitting diode; Space charge

  19. Coupled optical and electronic simulations of electrically pumped photonic-crystal-based light-emitting diodes

    E-Print Network [OSTI]

    Dutton, Robert W.

    trade-offs in electrically pumped photonic-crystal-based light-emitting diodes. A finite- toelectronic devices, such as light-emitting diodes LEDs and lasers. It has been suggested that a thin slabCoupled optical and electronic simulations of electrically pumped photonic-crystal-based light-emitting

  20. Effective intermediate layers for highly efficient stacked organic light-emitting devices

    E-Print Network [OSTI]

    studied in stacked organic light-emitting devices OLEDs . Stacked OLEDs with two identical emissive units organic light-emitting diode OLED device.1­3 The first three-color SOLED was reported in 1997, in whichEffective intermediate layers for highly efficient stacked organic light-emitting devices J. X. Sun

  1. 22.3 / H. J. Peng 22.3: High Efficiency Electrophosphorescent Organic Light Emitting Diodes

    E-Print Network [OSTI]

    in an organic light emitting diode (OLEDs) based on tris(phenyl pyridine)iridium [Ir(ppy)3]. Using. The improvement is due to a carefully designed microcavity. 1. Introduction Organic light emitting diodes (OLEDs rate can be enhanced due to Purcell effect. Therefore, a microcaivty OLED should emit more light than

  2. DNA Bases Thymine and Adenine in Bio-Organic Light Emitting Diodes

    E-Print Network [OSTI]

    Cincinnati, University of

    -7707 USA. We report on the use of nucleic acid bases (NBs) in organic light emitting diodes (OLEDs). NBs. DNA has been used in organic light-emitting diodes (OLEDs)4,5,7­14 yielding significant increasesDNA Bases Thymine and Adenine in Bio-Organic Light Emitting Diodes Eliot F. Gomez1 , Vishak

  3. High performance flexible top-emitting warm-white organic light-emitting devices and chromaticity shift mechanism

    SciTech Connect (OSTI)

    Shi, Hongying; Deng, Lingling; Chen, Shufen E-mail: wei-huang@njupt.edu.cn; Xu, Ying; Zhao, Xiaofei; Cheng, Fan; Huang, Wei E-mail: wei-huang@njupt.edu.cn; Jiangsu-Singapore Joint Research Center for Organic/Bio- Electronics and Information Displays and Institute of Advanced Materials, Nanjing University of Technology, Nanjing 211816

    2014-04-15

    Flexible warm-white top-emitting organic light-emitting devices (TEOLEDs) are fabricated onto PET substrates with a simple semi-transparent cathode Sm/Ag and two-color phosphors respectively doped into a single host material TCTA. By adjusting the relative position of the orange-red EML sandwiched between the blue emitting layers, the optimized device exhibits the highest power/current efficiency of 8.07 lm/W and near 13 cd/A, with a correlated color temperature (CCT) of 4105 K and a color rendering index (CRI) of 70. In addition, a moderate chromaticity variation of (-0.025, +0.008) around warm white illumination coordinates (0.45, 0.44) is obtained over a large luminance range of 1000 to 10000 cd/m{sup 2}. The emission mechanism is discussed via delta-doping method and single-carrier device, which is summarized that the carrier trapping, the exciton quenching, the mobility change and the recombination zone alteration are negative to color stability while the energy transfer process and the blue/red/blue sandwiched structure are contributed to the color stability in our flexible white TEOLEDs.

  4. EIS-0249: Medical Isotopes Production Project

    Broader source: Energy.gov [DOE]

    This EIS evaluates the potential environmental impacts of a proposal to establish a production capability for molybdenum-99 (Mo-99) and related medical isotopes.

  5. Strategic Isotope Production | ornl.gov

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

    Testing facility (IMET) are routinely used in the production, purification, packaging, and shipping of a number of isotopes of national importance, including: 75Se, 63Ni,...

  6. Stable Isotope Protocols: Sampling and Sample Processing

    E-Print Network [OSTI]

    Levin, Lisa A; Currin, Carolyn

    2012-01-01

    plants, benthic microalgae [BMI], benthic macroalgae) andin a dessicator, prior to analysis. A.2 Benthic microalgaeBenthic microalgae (BMI) can be collected for isotope

  7. Integration of Nontraditional Isotopic Systems Into Reaction...

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

    Nontraditional Isotopic Systems Into Reaction-Transport Models of EGS For Exploration, Evaluation of Water-Rock Interaction, and Impacts of Water Chemistry on Reservoir...

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

    E-Print Network [OSTI]

    Choi, Jae Ik

    2014-01-01

    application in white light emitting diode,” J. Mater. Res. ,S.Y. Choi. “White light-emitting diodes of GaN-based Sr 2phosphor for white light-emitting diodes prepared by sol–gel

  9. Big Bang Nucleosynthesis and the Helium Isotope Ratio

    E-Print Network [OSTI]

    Ryan Cooke

    2015-10-09

    The conventional approach to search for departures from the standard model of physics during Big Bang Nucleosynthesis involves a careful, and subtle measurement of the mass fraction of baryons consisting of helium. Recent measurements of this quantity tentatively support new physics beyond the standard model but, historically, this method has suffered from hidden systematic uncertainties. In this letter, I show that a combined measurement of the primordial deuterium abundance and the primordial helium isotope ratio has the potential to provide a complementary and reliable probe of new physics beyond the standard model. Using the recent determination of the primordial deuterium abundance and assuming that the measured pre-solar 3He/4He meteoritic abundance reflects the primordial value, a bound can be placed on the effective number of neutrino species, Neff(BBN) = 3.01 (+0.95 -0.76, with 95 per cent confidence). Although this value of Neff supports the standard model, it is presently unclear if the pre-solar 3He/4He ratio reflects the primordial value. New astrophysical measurements of the helium isotope ratio in near-pristine environments, together with updated calculations and experimental values of several important nuclear reactions (some of which are already being attempted), will lead to much improved limits on possible departures from the standard model. To this end, I describe an analysis strategy to measure the 3He I flux emitted from nearby low metallicity H II regions. The proposed technique can be attempted with the next generation of large telescopes, and will be easier to realize in metal-poor H II regions with quiescent kinematics.

  10. Discovery of Isotopes of Elements with Z $\\ge$ 100

    E-Print Network [OSTI]

    M. Thoennessen

    2012-03-09

    Currently, 163 isotopes of elements with Z $\\ge$ 100 have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  11. Alternating current long range alpha particle detector

    DOE Patents [OSTI]

    MacArthur, D.W.; McAtee, J.L.

    1993-02-16

    An alpha particle detector, utilizing alternating currents, which is capable of detecting alpha particles from distinct sources. The use of alternating currents allows use of simpler ac circuits which, in turn, are not susceptible to dc error components. It also allows the benefit of gas gain, if desired. In the invention, a voltage source creates an electric field between two conductive grids, and between the grids and a conductive enclosure. Air containing air ions created by collision with alpha particles is drawn into the enclosure and detected. In some embodiments, the air flow into the enclosure is interrupted, creating an alternating flow of ions. In another embodiment, a modulated voltage is applied to the grid, also modulating the detection of ions.

  12. Synthesis of peptide .alpha.-thioesters

    DOE Patents [OSTI]

    Camarero, Julio A. (Livermore, CA); Mitchell, Alexander R. (Livermore, CA); De Yoreo, James J. (Clayton, CA)

    2008-08-19

    Disclosed herein is a new method for the solid phase peptide synthesis (SPPS) of C-terminal peptide .alpha. thioesters using Fmoc/t-Bu chemistry. This method is based on the use of an aryl hydrazine linker, which is totally stable to conditions required for Fmoc-SPPS. When the peptide synthesis has been completed, activation of the linker is achieved by mild oxidation. The oxidation step converts the acyl-hydrazine group into a highly reactive acyl-diazene intermediate which reacts with an .alpha.-amino acid alkylthioester (H-AA-SR) to yield the corresponding peptide .alpha.-thioester in good yield. A variety of peptide thioesters, cyclic peptides and a fully functional Src homology 3 (SH3) protein domain have been successfully prepared.

  13. Nuclear diagnostic for fast alpha particles

    DOE Patents [OSTI]

    Grisham, Larry R. (Lawrence Township, Mercer County, NJ); Post, Jr., Douglass E. (Belle Mead, NJ); Dawson, John M. (Pacific Palisades, CA)

    1986-01-01

    Measurement of the velocity distribution of confined energetic alpha particles resulting from deuterium-tritium fusion reactions in a magnetically contained plasma is provided. The fusion plasma is seeded with energetic boron neutrals for producing, by means of the reaction .sup.10 B (.alpha.,n) .sup.13 N reaction, radioactive nitrogen nuclei which are then collected by a probe. The radioactivity of the probe is then measured by conventional techniques in determining the energy distribution of the alpha particles in the plasma. In a preferred embodiment, diborane gas (B.sub.2 H.sub.6) is the source of the boron neutrals to produce .sup.13 N which decays almost exclusively by positron emission with a convenient half-life of 10 minutes.

  14. Uranium isotopes fingerprint biotic reduction

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

    Stylo, Malgorzata; Neubert, Nadja; Wang, Yuheng; Monga, Nikhil; Romaniello, Stephen J.; Weyer, Stefan; Bernier-Latmani, Rizlan

    2015-04-20

    Knowledge of paleo-redox conditions in the Earth’s history provides a window into events that shaped the evolution of life on our planet. The role of microbial activity in paleo-redox processes remains unexplored due to the inability to discriminate biotic from abiotic redox transformations in the rock record. The ability to deconvolute these two processes would provide a means to identify environmental niches in which microbial activity was prevalent at a specific time in paleo-history and to correlate specific biogeochemical events with the corresponding microbial metabolism. Here, we demonstrate that the isotopic signature associated with microbial reduction of hexavalent uranium (U),more »i.e., the accumulation of the heavy isotope in the U(IV) phase, is readily distinguishable from that generated by abiotic uranium reduction in laboratory experiments. Thus, isotope signatures preserved in the geologic record through the reductive precipitation of uranium may provide the sought-after tool to probe for biotic processes. Because uranium is a common element in the Earth’s crust and a wide variety of metabolic groups of microorganisms catalyze the biological reduction of U(VI), this tool is applicable to a multiplicity of geological epochs and terrestrial environments. The findings of this study indicate that biological activity contributed to the formation of many authigenic U deposits, including sandstone U deposits of various ages, as well as modern, Cretaceous, and Archean black shales. In addition, engineered bioremediation activities also exhibit a biotic signature, suggesting that, although multiple pathways may be involved in the reduction, direct enzymatic reduction contributes substantially to the immobilization of uranium.« less

  15. Recipient luminophoric mediums having narrow spectrum luminescent materials and related semiconductor light emitting devices and methods

    DOE Patents [OSTI]

    LeToquin, Ronan P; Tong, Tao; Glass, Robert C

    2014-12-30

    Light emitting devices include a light emitting diode ("LED") and a recipient luminophoric medium that is configured to down-convert at least some of the light emitted by the LED. In some embodiments, the recipient luminophoric medium includes a first broad-spectrum luminescent material and a narrow-spectrum luminescent material. The broad-spectrum luminescent material may down-convert radiation emitted by the LED to radiation having a peak wavelength in the red color range. The narrow-spectrum luminescent material may also down-convert radiation emitted by the LED into the cyan, green or red color range.

  16. Spatial periphery of lithium isotopes

    SciTech Connect (OSTI)

    Galanina, L. I., E-mail: galan_lidiya@mail.ru; Zelenskaja, N. S. [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation)

    2013-12-15

    The spatial structure of lithium isotopes is studied with the aid of the charge-exchange and (t, p) reactions on lithium nuclei. It is shown that an excited isobaric-analog state of {sup 6}Li (0{sup +}, 3.56MeV) has a halo structure formed by a proton and a neutron, that, in the {sup 9}Li nucleus, there is virtually no neutron halo, and that {sup 11}Li is a Borromean nucleus formed by a {sup 9}Li core and a two-neutron halo manifesting itself in cigar-like and dineutron configurations.

  17. Uranium molecular laser isotope separation

    SciTech Connect (OSTI)

    Jensen, R.J.; Sullivan, A.

    1982-01-01

    The Molecular Laser Isotope Separation program is moving into the engineering phase, and it is possible to determine in some detail the plant cost terms involved in the process economics. A brief description of the MLIS process physics is given as a motivation to the engineering and economics discussion. Much of the plant cost arises from lasers and the overall optical system. In the paper, the authors discuss lasers as operating units and systems, along with temporal multiplexing and Raman shifting. Estimates of plant laser costs are given.

  18. Testing the Mutually Enhanced Magicity Effect in Nuclear Incompressibility via the Giant Monopole Resonance in the $^{204,206,208}$Pb Isotopes

    E-Print Network [OSTI]

    D. Patel; U. Garg; M. Fujiwara; T. Adachi; H. Akimune; G. P. A. Berg; M. N. Harakeh; M. Itoh; C. Iwamoto; A. Long; J. T. Matta; T. Murakami; A. Okamoto; K. Sault; R. Talwar; M. Uchida; M. Yosoi

    2013-08-09

    Using inelastic $\\alpha$-scattering at extremely forward angles, including $0^\\circ$, the strength distributions of the isoscalar giant monopole resonance (ISGMR) have been measured in the $^{204,206,208}$Pb isotopes in order to examine the proposed mutually enhanced magicity (MEM) effect on the nuclear incompressibility. The MEM effect had been suggested as a likely explanation of the "softness" of nuclear incompressibility observed in the ISGMR measurements in the Sn and Cd isotopes. Our experimental results rule out any manifestation of the MEM effect in nuclear incompressibility and leave the question of the softness of the open-shell nuclei unresolved still.

  19. Workshop on Precision Measurements of alphas

    E-Print Network [OSTI]

    S. Bethke; A. H. Hoang; S. Kluth; J. Schieck; I. W. Stewart; S. Aoki; M. Beneke; J. Blumlein; N. Brambilla; S. Brodsky; S. Descotes-Genon; J. Erler; S. Forte; T. Gehrmann; C. Glasman; M. Golterman; S. Hashimoto; A. Kronfeld; J. Kuhn; P. Lepage; A. Martin; V. Mateu; S. Menke; Y. Nomura; C. Pahl; F. Petriello; A. Pich; K. Rabbertz; G. Salam; H. Schulz; R. Sommer; M. Steinhauser; B. Webber; CP. Yuan; G. Zanderighi

    2011-10-22

    These are the proceedings of the "Workshop on Precision Measurements of alphas" held at the Max-Planck-Institute for Physics, Munich, February 9-11, 2011. The workshop explored in depth the determination of alphas(mZ) in the MS-bar scheme from the key categories where high precision measurements are currently being made, including DIS and global PDF fits, tau-decays, electroweak precision observables and Z-decays, event-shapes, and lattice QCD. These proceedings contain a short summary contribution from the speakers, as well as the lists of authors, conveners, participants, and talks.

  20. Fan-less long range alpha detector

    DOE Patents [OSTI]

    MacArthur, D.W.; Bounds, J.A.

    1994-05-10

    A fan-less long range alpha detector is disclosed which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces. 2 figures.

  1. Modelling Bose Einstein Correlations via Elementary Emitting Cells

    E-Print Network [OSTI]

    Oleg Utyuzh; Grzegorz Wilk; Zbigniew Wlodarczyk

    2007-04-24

    We propose a method of numerical modeling Bose Einstein Correlations by using the notion of Elementary Emitting Cells (EEC). They are intermediary objects containing identical bosons and are supposed to be produced independently during the hadronization process. Only bosons in EEC, which represents a single quantum state here, are subjected to the effects of Bose-Einstein (BE) statistics, which forces them to follow a geometrical distribution. There are no such effects between particles from different EECs. We illustrate our proposition by calculating a representative number of typical distributions and discussing their sensitivity to EECs and their characteristics.

  2. High efficiency III-nitride light-emitting diodes

    DOE Patents [OSTI]

    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.

  3. Solid-state radiation-emitting compositions and devices

    DOE Patents [OSTI]

    Ashley, C.S.; Brinker, C.J.; Reed, S.; Walko, R.J.

    1992-08-11

    The invention relates to a composition for the volumetric generation of radiation, wherein a first substance functions as a source of exciting radiation, and a second substance interacts with the exciting radiation to provide a second radiation. The compositions comprise a porous substrate which is loaded with: a source of exciting radiation, a component capable of emitting radiation upon interaction with the exciting radiation, or both. Preferably, the composition is an aerogel substrate loaded with both a source of exciting radiation, such as tritium, and a component capable of interacting with the exciting radiation, e.g., a phosphor, to produce radiation of a second energy. 4 figs.

  4. Fabrication of poly(p-phenyleneacetylene) light-emitting diodes

    DOE Patents [OSTI]

    Shinar, Joseph (Ames, IA); Swanson, Leland S. (Ames, IA); Lu, Feng (Ames, IA); Ding, Yiwei (Ames, IA)

    1994-08-02

    Acetylene containing poly(p-phenyleneacetylene) (PPA) - based light-emitting diodes (LEDs) are provided. The LEDs are fabricated by coating a hole-injecting electrode, preferably an indium tin oxide (ITO) coated glass substrate, with a PPA polymer, such as a 2,5-dibutoxy or a 2,5-dihexoxy derivative of PPA, dissolved in an organic solvent. This is then followed by evaporating a layer of material capable of injecting electrons, such as A1 or A1/Ca, onto the polymer to form a base electrode. This composition is then annealed to form efficient EL diodes.

  5. Poly (p-phenyleneneacetylene) light-emitting diodes

    DOE Patents [OSTI]

    Shinar, Joseph (Ames, IA); Swanson, Leland S. (Ames, IA); Lu, Feng (Ames, IA); Ding, Yiwei (Ames, IA); Barton, Thomas J. (Ames, IA); Vardeny, Zeev V. (Salt Lake City, UT)

    1994-10-04

    Acetylene containing poly(p-phenyleneacetylene) (PPA) - based light-emitting diodes (LEDs) are provided. The LEDs are fabricated by coating a hole-injecting electrode, preferably an indium tin oxide (ITO) coated glass substrate, with a PPA polymer, such as a 2,5-dibutoxy or a 2,5-dihexoxy derivative of PPA, dissolved in an organic solvent. This is then followed by evaporating a layer of material capable of injecting electrons, such as Al or Al/Ca, onto the polymer to form a base electrode. This composition is then annealed to form efficient EL diodes.

  6. Fabrication of poly(p-phenyleneacetylene) light-emitting diodes

    DOE Patents [OSTI]

    Shinar, J.; Swanson, L.S.; Lu, F.; Ding, Y.

    1994-08-02

    Acetylene-containing poly(p-phenyleneacetylene) (PPA)-based light-emitting diodes (LEDs) are provided. The LEDs are fabricated by coating a hole-injecting electrode, preferably an indium tin oxide (ITO) coated glass substrate, with a PPA polymer, such as a 2,5-dibutoxy or a 2,5-dihexoxy derivative of PPA, dissolved in an organic solvent. This is then followed by evaporating a layer of material capable of injecting electrons, such as Al or Al/Ca, onto the polymer to form a base electrode. This composition is then annealed to form efficient EL diodes. 8 figs.

  7. Organimetallic Fluorescent Complex Polymers For Light Emitting Applications

    DOE Patents [OSTI]

    Shi, Song Q. (Phoenix, AZ); So, Franky (Tempe, AZ)

    1997-10-28

    A fluorescent complex polymer with fluorescent organometallic complexes connected by organic chain spacers is utilized in the fabrication of light emitting devices on a substantially transparent planar substrate by depositing a first conductive layer having p-type conductivity on the planar surface of the substrate, depositing a layer of a hole transporting and electron blocking material on the first conductive layer, depositing a layer of the fluorescent complex polymer on the layer of hole transporting and electron blocking material as an electron transporting emissive layer and depositing a second conductive layer having n-type conductivity on the layer of fluorescent complex polymer.

  8. Solid-state radiation-emitting compositions and devices

    DOE Patents [OSTI]

    Ashley, Carol S. (Albuquerque, NM); Brinker, C. Jeffrey (Albuquerque, NM); Reed, Scott (Albuquerque, NM); Walko, Robert J. (Albuquerque, NM)

    1992-01-01

    The invention relates to a composition for the volumetric generation of radiation, wherein a first substance functions as a source of exciting radiation, and a second substance interacts with the exciting radiation to provide a second radiation. The compositions comprise a porous substrate which is loaded with: a source of exciting radiation, a component capable of emitting radiation upon interaction with the exciting radiation, or both. Preferably, the composition is an aerogel substrate loaded with both a source of exciting radiation, such as tritium, and a component capable of interacting with the exciting radiation, e.g., a phosphor, to produce radiation of a second energy.

  9. Isotopic Analysis- Gas At Long Valley Caldera Geothermal Area...

    Open Energy Info (EERE)

    Isotopic Analysis- Gas At Long Valley Caldera Geothermal Area (Farrar, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic...

  10. Isotopic Analysis- Gas At Long Valley Caldera Geothermal Area...

    Open Energy Info (EERE)

    Isotopic Analysis- Gas At Long Valley Caldera Geothermal Area (Welhan, Et Al., 1988) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic...

  11. BETA DECAY MEASUREMENTS OF NEUTRON DEFICIENT CESIUM ISOTOPES

    E-Print Network [OSTI]

    Parry, R.F.

    2010-01-01

    OF NEUTRON DEFICIENT CESIUM ISOTOPES by Roger Franklin Parryof Neutron Deficient Cesium Isotopes Table of ContentsReferences Wapstra xenon and cesium mass excess values 108

  12. Strontium Isotopes Test Long-Term Zonal Isolation of Injected...

    Office of Scientific and Technical Information (OSTI)

    Strontium Isotopes Test Long-Term Zonal Isolation of Injected and Marcellus Formation Water after Hydraulic Fracturing Citation Details In-Document Search Title: Strontium Isotopes...

  13. Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes...

    Office of Environmental Management (EM)

    Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes Presentation from the 34th Tritium Focus Group...

  14. Advances in Hydrogen Isotope Separation Using Thermal Cycling...

    Office of Environmental Management (EM)

    Hydrogen Isotope Separation Using Thermal Cycling Absorption Process (TCAP) Advances in Hydrogen Isotope Separation Using Thermal Cycling Absorption Process (TCAP) Presentation...

  15. Hydrogen Isotope Research Center (HRC), University of Toyama...

    Office of Environmental Management (EM)

    Hydrogen Isotope Research Center (HRC), University of Toyama Hydrogen Isotope Research Center (HRC), University of Toyama Presentation from the 34th Tritium Focus Group Meeting...

  16. 2008 Workshop on The Nation's Needs for Isotopes: Present and...

    Office of Science (SC) Website

    and radioactive isotope products that are used worldwide. Hundreds of applications in medicine, industry, national security and research depend on isotopes as vital components. The...

  17. Permeation of Multiple Isotopes in the Transition Between Surface...

    Office of Environmental Management (EM)

    Permeation of Multiple Isotopes in the Transition Between Surface- and Diffusion-Limited Regimes Permeation of Multiple Isotopes in the Transition Between Surface- and...

  18. Isotopic Analysis At Central Nevada Seismic Zone Region (Kennedy...

    Open Energy Info (EERE)

    Isotopic Analysis At Central Nevada Seismic Zone Region (Kennedy & Van Soest, 2007) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic...

  19. Positive and inverse isotope effect on superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2009-09-04

    This article improves the BCS theory to include the inverse isotope effect on superconductivity. An affective model can be deduced from the model including electron-phonon interactions, and the phonon-induced attraction is simply and clearly explained on the electron Green function. The focus of this work is on how the positive or inverse isotope effect occurs in superconductors.

  20. [Carbon isotope fractionation inplants]. Final report

    SciTech Connect (OSTI)

    O`Leary, M.H.

    1990-12-31

    The objectives of this research are: To develop a theoretical and experimental framework for understanding isotope fractionations in plants; and to develop methods for using this isotope fractionation for understanding the dynamics of CO{sub 2} fixation in plants. Progress is described.

  1. The Quest for the Heaviest Uranium Isotope

    E-Print Network [OSTI]

    S. Schramm; D. Gridnev; D. V. Tarasov; V. N. Tarasov; W. Greiner

    2012-01-17

    We study Uranium isotopes and surrounding elements at very large neutron number excess. Relativistic mean field and Skyrme-type approaches with different parametrizations are used in the study. Most models show clear indications for isotopes that are stable with respect to neutron emission far beyond N=184 up to the range of around N=258.

  2. Efficient palladium isotope chromatograph for hydrogen (EPIC)

    SciTech Connect (OSTI)

    Embury, M.C.; Ellefson, R.E.; Melke, H.B. )

    1992-03-01

    The Efficient Palladium Isotope Chromatograph (EPIC) is a rapid cycling, computer-operated displacement chromatograph for the separation of hydrogen isotopes. EPIC incorporates several features that optimize product throughput and purity. This paper describes this palladium displacement chromatograph, the operations with protium and deuterium, and the design modifications for operation with tritium.

  3. ISOTOPES

    E-Print Network [OSTI]

    Lederer, C. Michael

    2013-01-01

    constructed to enrich liquid UF6 slightly as feed for thej) b. Optimum a. s: .X. UF6 feed, (kg per year) XBL 7912 -

  4. ISOTOPES

    E-Print Network [OSTI]

    Lederer, C. Michael

    2013-01-01

    scale use of gas centrifuges for uranium is imminent, andUranium Enrichment (1978). United States Gas Centrifuge

  5. Isotopes

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation CurrentHenryInhibitingInteractivePGAS andUniversityCancer therapy gets

  6. Device and method for separating oxygen isotopes

    DOE Patents [OSTI]

    Rockwood, Stephen D. (Los Alamos, NM); Sander, Robert K. (Los Alamos, NM)

    1984-01-01

    A device and method for separating oxygen isotopes with an ArF laser which produces coherent radiation at approximately 193 nm. The output of the ArF laser is filtered in natural air and applied to an irradiation cell where it preferentially photodissociates molecules of oxygen gas containing .sup.17 O or .sup.18 O oxygen nuclides. A scavenger such as O.sub.2, CO or ethylene is used to collect the preferentially dissociated oxygen atoms and recycled to produce isotopically enriched molecular oxygen gas. Other embodiments utilize an ArF laser which is narrowly tuned with a prism or diffraction grating to preferentially photodissociate desired isotopes. Similarly, desired mixtures of isotopic gas can be used as a filter to photodissociate enriched preselected isotopes of oxygen.

  7. Transformer Recharging with Alpha Channeling in Tokamaks

    SciTech Connect (OSTI)

    N.J. Fisch

    2009-12-21

    Transformer recharging with lower hybrid waves in tokamaks can give low average auxiliary power if the resistivity is kept high enough during the radio frequency (rf) recharging stage. At the same time, operation in the hot ion mode via alpha channeling increases the effective fusion reactivity. This paper will address the extent to which these two large cost saving steps are compatible. __________________________________________________

  8. Monitoring lensed starlight emitted close to the Galactic Center

    E-Print Network [OSTI]

    Adi Nusser; Tom Broadhurst

    2004-07-12

    We describe the feasibility of detecting the gravitational deflection of light emitted by stars moving under the influence of the massive object at the Galactic center. Light emitted by a star orbiting behind the central mass has a smaller impact parameter than the star itself, and suffers the effect of gravitational lensing, providing a closer probe of the central mass distribution and hence a stricter test of the black hole hypothesis. A mass of $4.3\\times 10^{6} M_{\\odot}$ causes a $0.1-2\\rm mas$ deviation in the apparent position of orbiting stars projected within $10^{\\circ}$ of the line of sight to the galactic center. In addtion, we may uniquely constrain the distance to the center of the galaxy because lensing deflections constrain the ratio $\\rg/R_{0}$ of the Schwarzschild radius to the distance to the black hole, $R_{o}$, whereas the ratio $\\rg/R_{o}^{3}$ is obtained by fitting the orbit.

  9. Atomic vapor laser isotope separation of lead-210 isotope

    DOE Patents [OSTI]

    Scheibner, Karl F. (Tracy, CA); Haynam, Christopher A. (Pleasanton, CA); Johnson, Michael A. (Pleasanton, CA); Worden, Earl F. (Diablo, CA)

    1999-01-01

    An isotopically selective laser process and apparatus for removal of Pb-210 from natural lead that involves a one-photon near-resonant, two-photon resonant excitation of one or more Rydberg levels, followed by field ionization and then electrostatic extraction. The wavelength to the near-resonant intermediate state is counter propagated with respect to the second wavelength required to populate the final Rydberg state. This scheme takes advantage of the large first excited state cross section, and only modest laser fluences are required. The non-resonant process helps to avoid two problems: first, stimulated Raman Gain due to the nearby F=3/2 hyperfine component of Pb-207 and, second, direct absorption of the first transition process light by Pb-207.

  10. Atomic vapor laser isotope separation of lead-210 isotope

    DOE Patents [OSTI]

    Scheibner, K.F.; Haynam, C.A.; Johnson, M.A.; Worden, E.F.

    1999-08-31

    An isotopically selective laser process and apparatus for removal of Pb-210 from natural lead that involves a one-photon near-resonant, two-photon resonant excitation of one or more Rydberg levels, followed by field ionization and then electrostatic extraction. The wavelength to the near-resonant intermediate state is counter propagated with respect to the second wavelength required to populate the final Rydberg state. This scheme takes advantage of the large first excited state cross section, and only modest laser fluences are required. The non-resonant process helps to avoid two problems: first, stimulated Raman Gain due to the nearby F=3/2 hyperfine component of Pb-207 and, second, direct absorption of the first transition process light by Pb-207. 5 figs.

  11. Study of alpha background in a dark matter detector

    E-Print Network [OSTI]

    Yegoryan, Hayk

    2010-01-01

    Alpha background, specifically from radon and its progeny in the uranium and thorium chains, has been a major issue in dark matter detectors. This work focuses on alpha background presence in the DMTPC experiment by examining ...

  12. Nuclear isospin asymmetry in $\\alpha$ decays of heavy nuclei

    E-Print Network [OSTI]

    Shin, Eunkyoung; Hyun, Chang Ho; Oh, Yongseok

    2015-01-01

    The effects of nuclear isospin asymmetry on $\\alpha$ decay lifetimes of heavy nuclei are investigated within various phenomenological models of nuclear potential for the $\\alpha$ particle. We consider the widely used simple square well potential and Woods-Saxon potential, and modify them by including an isospin asymmetry term. We then suggest a model for the potential of the $\\alpha$ particle motivated by a microscopic phenomenological approach of the Skyrme force model, which naturally introduce the isospin dependent form of the nuclear potential for the $\\alpha$ particle. The empirical $\\alpha$ decay lifetime formula of Viola and Seaborg is also modified to include isospin asymmetry effects. The obtained $\\alpha$ decay half-lives are in good agreement with the experimental data and we find that including the nuclear isospin effects somehow improves the theoretical results for $\\alpha$ decay half-lives. The implications of these results are discussed and the predictions on the $\\alpha$ decay lifetimes of sup...

  13. Antibody-mediated reduction of {alpha}-ketoamides

    DOE Patents [OSTI]

    Schultz, P.G.; Gallop, M.A.

    1998-06-09

    Monoclonal antibodies raised against a 4-nitrophenyl phosphonate hapten catalyze the stereospecific reduction of an {alpha}-ketoamide to the corresponding {alpha}-hydroxyamide in the presence of an appropriate reducing agent.

  14. The effects of alpha particle irradiation on stainless steel 

    E-Print Network [OSTI]

    Shipp, John Douglas

    1999-01-01

    A Monte Carlo code was developed to calculate the alpha particle emission rate from WGPu. It yielded information pertaining to the alpha particle source strength at the WGPU and stainless steel interface as well as the damage production and He...

  15. DETERMINATION OF 237NP AND PU ISOTOPES IN LARGE SOIL SAMPLES BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY

    SciTech Connect (OSTI)

    Maxwell, S.

    2010-07-26

    A new method for the determination of {sup 237}Np and Pu isotopes in large soil samples has been developed that provides enhanced uranium removal to facilitate assay by inductively coupled plasma mass spectrometry (ICP-MS). This method allows rapid preconcentration and separation of plutonium and neptunium in large soil samples for the measurement of {sup 237}Np and Pu isotopes by ICP-MS. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via {sup 238}U peak tailing. The method provides enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then transferring Pu to DGA resin for additional purification. The decontamination factor for removal of uranium from plutonium for this method is greater than 1 x 10{sup 6}. Alpha spectrometry can also be applied so that the shorter-lived {sup 238}Pu isotope can be measured successfully. {sup 239}Pu, {sup 242}Pu and {sup 237}Np were measured by ICP-MS, while {sup 236}Pu and {sup 238}Pu were measured by alpha spectrometry.

  16. Atomic vapor laser isotope separation

    SciTech Connect (OSTI)

    Stern, R.C.; Paisner, J.A.

    1985-11-08

    Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements.

  17. Apparatus for storing hydrogen isotopes

    DOE Patents [OSTI]

    McMullen, John W. (Los Alamos, NM); Wheeler, Michael G. (Los Alamos, NM); Cullingford, Hatice S. (Houston, TX); Sherman, Robert H. (Los Alamos, NM)

    1985-01-01

    An improved method and apparatus for storing isotopes of hydrogen (especially tritium) are provided. The hydrogen gas(es) is (are) stored as hydrides of material (for example uranium) within boreholes in a block of copper. The mass of the block is critically important to the operation, as is the selection of copper, because no cooling pipes are used. Because no cooling pipes are used, there can be no failure due to cooling pipes. And because copper is used instead of stainless steel, a significantly higher temperature can be reached before the eutectic formation of uranium with copper occurs, (the eutectic of uranium with the iron in stainless steel forming at a significantly lower temperature).

  18. Isotopic Studies of Contaminant Transport at the Hanford Site, WA

    E-Print Network [OSTI]

    Christensen, J.N.; Conrad, M.E.; DePaolo, D.J.; Dresel, P.E.

    2008-01-01

    1977. Subcommission on geochronology: Convention on the useby W. Sharp, Berkeley Geochronology Center). Isotopic

  19. Electroluminescence property of organic light emitting diode (OLED)

    SciTech Connect (OSTI)

    Özdemir, Orhan; Kavak, Pelin; Saatci, A. Evrim; Gökdemir, F. P?nar; Menda, U. Deneb; Can, Nursel; Kutlu, Kubilay; Tekin, Emine; Pravadal?, Selin

    2013-12-16

    Transport properties of electrons and holes were investigated not only in a anthracene-containing poly(p-phenylene-ethynylene)- alt - poly(p-phenylene-vinylene) (PPE-PPV) polymer (AnE-PVstat) light emitting diodes (OLED) but also in an ITO/Ag/polymer/Ag electron and ITO/PEDOT:PSS/polymer/Au hole only devices. Mobility of injected carriers followed the Poole-Frenkel type conduction mechanism and distinguished in the frequency range due to the difference of transit times in admittance measurement. Beginning of light output took place at the turn-on voltage (or flat band voltage), 1.8 V, which was the difference of energy band gap of polymer and two barrier offsets between metals and polymer.

  20. Electrically pumped edge-emitting photonic bandgap semiconductor laser

    DOE Patents [OSTI]

    Lin, Shawn-Yu; Zubrzycki, Walter J.

    2004-01-06

    A highly efficient, electrically pumped edge-emitting semiconductor laser based on a one- or two-dimensional photonic bandgap (PBG) structure is described. The laser optical cavity is formed using a pair of PBG mirrors operating in the photonic band gap regime. Transverse confinement is achieved by surrounding an active semiconductor layer of high refractive index with lower-index cladding layers. The cladding layers can be electrically insulating in the passive PBG mirror and waveguide regions with a small conducting aperture for efficient channeling of the injection pump current into the active region. The active layer can comprise a quantum well structure. The quantum well structure can be relaxed in the passive regions to provide efficient extraction of laser light from the active region.

  1. Method of electroplating a conversion electron emitting source on implant

    DOE Patents [OSTI]

    Srivastava, Suresh C. (Setauket, NY); Gonzales, Gilbert R. (New York, NY); Adzic, Radoslav (East Setauket, NY); Meinken, George E. (Middle Island, NY)

    2012-02-14

    Methods for preparing an implant coated with a conversion electron emitting source (CEES) are disclosed. The typical method includes cleaning the surface of the implant; placing the implant in an activating solution comprising hydrochloric acid to activate the surface; reducing the surface by H.sub.2 evolution in H.sub.2SO.sub.4 solution; and placing the implant in an electroplating solution that includes ions of the CEES, HCl, H.sub.2SO.sub.4, and resorcinol, gelatin, or a combination thereof. Alternatively, before tin plating, a seed layer is formed on the surface. The electroplated CEES coating can be further protected and stabilized by annealing in a heated oven, by passivation, or by being covered with a protective film. The invention also relates to a holding device for holding an implant, wherein the device selectively prevents electrodeposition on the portions of the implant contacting the device.

  2. Solid-state radiation-emitting compositions and devices

    DOE Patents [OSTI]

    Ashley, Carol S. (14316 Bauer Rd., NE., Albuquerque, NM 87123); Brinker, C. Jeffrey (14 Eagle Nest Dr., NE., Albuquerque, NM 87122); Reed, Scott (10308 Leymon Ct., NW., Albuquerque, NM 87114); Shepodd, Timothy J. (1838 Broadmore St., Livermore, CA 94550); Leonard, Leroy E. (4944 Ten Oaks Rd., Dayton, MD 21036); Ellefson, Robert E. (193 Elmwood Dr., Centerville, OH 45459); Gill, John T. (906 E. Linden Ave., Miamisburg, OH 45342); Walko, Robert J. (3215 Blume, NE., Albuquerque, NM 87111); Renschler, Clifford L. (7 Lagarto Rd., Tijeras, NM 87059)

    1992-01-01

    The invention relates to a composition for the volumetric generation of radiation, wherein a first substance functions as a source of exciting radiation, and a second substance interacts with the exciting radiation to provide a second radiation. The compositions comprise a porous substrate which is loaded with: a source of exciting radiation, a component capable of emitting radiation upon interaction with the exciting radiation, or both. In the composition, a composite is formed from a carrier material and at least one of the source of the exciting radiation or the component which is capable of interacting with the exciting radiation. The composite is then employed for loading a porous substrate, preferably an aerogel substrate.

  3. Blue fluorescent organic light emitting diodes with multilayered graphene anode

    SciTech Connect (OSTI)

    Hwang, Joohyun [OLED Lighting Research Team, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of)] [OLED Lighting Research Team, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of); Choi, Hong Kyw [Graphene Electronics Creative Research Section, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of)] [Graphene Electronics Creative Research Section, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of); Moon, Jaehyun; Shin, Jin-Wook; Joo, Chul Woong; Han, Jun-Han; Cho, Doo-Hee; Huh, Jin Woo [OLED Lighting Research Team, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of)] [OLED Lighting Research Team, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of); Choi, Sung-Yool [Graphene Electronics Creative Research Section, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of)] [Graphene Electronics Creative Research Section, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of); Lee, Jeong-Ik, E-mail: jiklee@etri.re.kr [OLED Lighting Research Team, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of)] [OLED Lighting Research Team, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of); Chu, Hye Yong [OLED Lighting Research Team, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of)] [OLED Lighting Research Team, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700 (Korea, Republic of)

    2012-10-15

    As an innovative anode for organic light emitting devices (OLEDs), we have investigated graphene films. Graphene has importance due to its huge potential in flexible OLED applications. In this work, graphene films have been catalytically grown and transferred to the glass substrate for OLED fabrications. We have successfully fabricated 2 mm × 2 mm device area blue fluorescent OLEDs with graphene anodes which showed 2.1% of external quantum efficiency at 1000 cd/m{sup 2}. This is the highest value reported among fluorescent OLEDs using graphene anodes. Oxygen plasma treatment on graphene has been found to improve hole injections in low voltage regime, which has been interpreted as oxygen plasma induced work function modification. However, plasma treatment also increases the sheet resistance of graphene, limiting the maximum luminance. In summary, our works demonstrate the practical possibility of graphene as an anode material for OLEDs and suggest a processing route which can be applied to various graphene related devices.

  4. The Multi-Isotope Process (MIP) Monitor Project: FY12 Progress and Accomplishments

    SciTech Connect (OSTI)

    Coble, Jamie B.; Orton, Christopher R.; Jordan, David V.; Schwantes, Jon M.; Bender, Sarah; Dayman, Kenneth J.; Unlu, Kenan; Landsberger, Sheldon

    2012-09-27

    The Multi-Isotope Process (MIP) Monitor, being developed at Pacific Northwest National Laboratory (PNNL), provides an efficient approach to monitoring the process conditions in reprocessing facilities in support of the goal of "...(minimization of) the risks of nuclear proliferation and terrorism." The MIP Monitor measures distributions of a suite of indicator (radioactive) isotopes present within product and waste streams of a nuclear reprocessing facility. These indicator isotopes are monitored on-line by gamma spectrometry and compared, in near-real-time, to spectral patterns representing "normal" process conditions using multivariate pattern recognition software. The monitor utilizes this multivariate analysis and gamma spectroscopy of reprocessing streams to detect small changes in the gamma spectrum, which may indicate changes in process conditions. Multivariate analysis methods common in chemometrics, such as principal component analysis (PCA) and partial least squares regression (PLS), act as pattern recognition techniques, which can detect small deviations from the expected, nominal condition. By targeting multiple gamma-emitting indicator isotopes, the MIP Monitor approach is compatible with the use of small, portable, relatively high-resolution gamma detectors that may be easily deployed throughout an existing facility. The automated multivariate analysis can provide a level of data obscurity, giving a built-in information barrier to protect sensitive or proprietary operational data. Proof-of-concept simulations and experiments have been performed in previous years to demonstrate the validity of this tool in a laboratory setting. Development of the MIP Monitor approach continues to evaluate the efficacy of the monitor for automated, real-time or near-real-time application. This report details follow-on research and development efforts sponsored by the U.S. Department of Energy Fuel Cycle Research and Development related to the MIP Monitor for fiscal year 2012 (FY12).

  5. Organic light-emitting device with a phosphor-sensitized fluorescent emission layer

    DOE Patents [OSTI]

    Forrest, Stephen (Ann Arbor, MI); Kanno, Hiroshi (Osaka, JP)

    2009-08-25

    The present invention relates to organic light emitting devices (OLEDs), and more specifically to OLEDS that emit light using a combination of fluorescent emitters and phosphorescent emitters. The emissive region of the devices of the present invention comprise at least one phosphor-sensitized layer which has a combined emission from a phosphorescent emitter and a fluorescent emitter. In preferred embodiments, the invention relates to white-emitting OLEDS (WOLEDs).

  6. Low Voltage, Low Power Organic Light Emitting Transistors for AMOLED Displays

    SciTech Connect (OSTI)

    McCarthy, M. A. [University of Florida, Gainesville; Liu, B. [University of Florida, Gainesville; Donoghue, E. P. [University of Florida, Gainesville; Kravchenko, Ivan I [ORNL; Kim, D. Y. [University of Florida, Gainesville; Reynolds, J. R. [University of Florida, Gainesville; So, Franky [University of Florida, Gainesville; Rinzler, A. G. [University of Florida, Gainesville

    2011-01-01

    Low voltage, low power dissipation, high aperture ratio organic light emitting transistors are demonstrated. The high level of performance is enabled by a carbon nanotube source electrode that permits integration of the drive transistor and the organic light emitting diode into an efficient single stacked device. Given the demonstrated performance, this technology could break the technical logjam holding back widespread deployment of active matrix organic light emitting displays at flat panel screen sizes.

  7. Short course on St-02 applications of isotope dilutions and isotopic measurements

    SciTech Connect (OSTI)

    Miller, P.

    1998-01-05

    This short course includes information on these topics and subtopics: (I) Nuclear Properties: (A) Historic roots; (B) Nomenclature; (C) Nuclear Stability and abundance; (D) Uses of isotopic techniques; (II) Instrumentation: (A) Sources; (B) Mass resolving elements; (C) Detectors; (III) Making Isotopic Measurements by ICP-MS: (A) Deadtime Correction; (B) Mass Discrimination; (C) Signal /Noise considerations; (IV) Applications and examples: (A) Isotope dilution; (B) Double Spike; (C) Biological Application; (D) Environmental Application; (E) Geological.

  8. Alpha Cluster Model of Atomic Nuclei

    E-Print Network [OSTI]

    Sosin, Zbigniew; Kallunkathariyil, Jinesh; ?ukasik, Jerzy; Paw?owski, Piotr

    2015-01-01

    The description of the nuclear system in its ground state and at low excitations based on the equation of state (EoS) around the saturation density is presented. In the expansion of the EoS around the saturation point additional spin polarization terms are taken into account. In addition for atomic nuclei a correction of the average nucleonic energy for the surface energy is introduced. The ground state configurations for the N=Z even-even nuclei, obtained with the proposed EoS, exhibit a clear cluster structure. At the nuclear surface these clusters can be identified as alpha particles. Taking into account an additional interaction between clusters the binding energy and sizes of the considered nuclei are very accurately described. From properties of the {\\alpha} particle, 3He and t limits of the EoS parameters are established.

  9. Automatically processed alpha-track radon monitor

    DOE Patents [OSTI]

    Langner, G.H. Jr.

    1993-01-12

    An automatically processed alpha-track radon monitor is provided which includes a housing having an aperture allowing radon entry, and a filter that excludes the entry of radon daughters into the housing. A flexible track registration material is located within the housing that records alpha-particle emissions from the decay of radon and radon daughters inside the housing. The flexible track registration material is capable of being spliced such that the registration material from a plurality of monitors can be spliced into a single strip to facilitate automatic processing of the registration material from the plurality of monitors. A process for the automatic counting of radon registered by a radon monitor is also provided.

  10. Automatically processed alpha-track radon monitor

    DOE Patents [OSTI]

    Langner, Jr., G. Harold (Mack, CO)

    1993-01-01

    An automatically processed alpha-track radon monitor is provided which includes a housing having an aperture allowing radon entry, and a filter that excludes the entry of radon daughters into the housing. A flexible track registration material is located within the housing that records alpha-particle emissions from the decay of radon and radon daughters inside the housing. The flexible track registration material is capable of being spliced such that the registration material from a plurality of monitors can be spliced into a single strip to facilitate automatic processing of the registration material from the plurality of monitors. A process for the automatic counting of radon registered by a radon monitor is also provided.

  11. Discovery of the $^{151}$Eu $\\alpha$ decay

    E-Print Network [OSTI]

    Casali, N; Orio, F; Pattavina, L; Beeman, J W; Bellini, F; Cardani, L; Dafinei, I; Di Domizio, S; Di Vacri, M L; Gironi, L; Kosmyna, M B; Nazarenko, B P; Nisi, S; Pessina, G; Piperno, G; Pirro, S; Rusconi, C; Shekhovtsov, A N; Tomei, C; Vignati, M

    2013-01-01

    We report on the observation of the $^{151}$Eu $\\alpha$ decay to the ground state of $^{147}$Pm. We measured a half-life of T_{1/2}=(4.62$\\pm$0.95(stat.)$\\pm$0.68(syst.))$\\times 10^{18}$ y and a Q-value of 1948.9$\\pm$6.9 keV, using a 6.15 g Li$_6$Eu(BO$_3$)$_3$ crystal operated as scintillating bolometer.

  12. A new seismic analysis of Alpha Centauri

    E-Print Network [OSTI]

    A. Thoul; R. Scuflaire; A. Noels; B. Vatovez; M. Briquet; M. -A. Dupret; J. Montalban

    2003-03-20

    Models of alpha Cen A & B have been computed using the masses determined by Pourbaix et al. (2002) and the data derived from the spectroscopic analysis of Neuforge and Magain (1997). The seismological data obtained by Bouchy and Carrier (2001, 2002) do help improve our knowledge of the evolutionary status of the system. All the constraints are satisfied with a model which gives an age of about 6 Gyr for the binary.

  13. A new seismic analysis of Alpha Centauri

    E-Print Network [OSTI]

    Thoul, A; Noels, A; Vatovez, B; Briquet, M; Dupret, M A; Montalban, J

    2003-01-01

    Models of alpha Cen A & B have been computed using the masses determined by Pourbaix et al. (2002) and the data derived from the spectroscopic analysis of Neuforge and Magain (1997). The seismological data obtained by Bouchy and Carrier (2001, 2002) do help improve our knowledge of the evolutionary status of the system. All the constraints are satisfied with a model which gives an age of about 6 Gyr for the binary.

  14. Oxygen isotopes in crystalline silicates of comet Wild 2: A comparison of oxygen isotope systematics between Wild 2 particles

    E-Print Network [OSTI]

    Meyers, Stephen R.

    Oxygen isotopes in crystalline silicates of comet Wild 2: A comparison of oxygen isotope 2012 Keywords: oxygen isotope ratios crystalline silicate comet 81P/Wild 2 solar system formation Stardust Abstract: Oxygen three-isotope ratios of nine crystalline silicate particles from comet Wild 2

  15. Energy Savings Estimates of Light Emitting Diodes in Niche Lighting Applications

    SciTech Connect (OSTI)

    none,

    2011-01-01

    This report is an analysis of niche markets and applications for light-emitting diodes (LEDs), undertaken on behalf of the U.S. Department of Energy.

  16. 2014-06-18 Issuance: Test Procedure for Integrated Light-Emitting...

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

    6-18 Issuance: Test Procedure for Integrated Light-Emitting Diode Lamps; Supplemental Notice of Proposed Rulemaking 2014-06-18 Issuance: Test Procedure for Integrated...

  17. Development of bottom-emitting 1300 nm vertical-cavity surface...

    Office of Scientific and Technical Information (OSTI)

    1300 nm vertical-cavity surface-emitting lasers. No abstract prepared. Authors: Fish, M. A. 1 ; Serkland, Darwin Keith ; Guilfoyle, Peter S. 1 ; Stone, Richard V. 1 ;...

  18. Demonstration Assessment of Light-Emitting Diode (LED) Area Lights for a Commercial Garage

    SciTech Connect (OSTI)

    None

    2008-11-01

    This U.S. Department of Energy GATEWAY Demonstration project studied the applicability of light-emitting diode (LED) luminaires for commercial parking garage applications.

  19. Energy Savings Estimates of Light Emitting Diodes in Niche Lighting Applications

    SciTech Connect (OSTI)

    None

    2008-10-01

    This report is an analysis of niche markets and applications for light-emitting diodes (LEDs), undertaken on behalf of the U.S. Department of Energy.

  20. High performance flexible top-emitting warm-white organic light...

    Office of Scientific and Technical Information (OSTI)

    TCTA. By adjusting the relative position of the orange-red EML sandwiched between the blue emitting layers, the optimized device exhibits the highest powercurrent efficiency of...

  1. Detection of alpha radiation in a beta radiation field

    DOE Patents [OSTI]

    Mohagheghi, Amir H. (Albuquerque, NM); Reese, Robert P. (Edgewood, NM)

    2001-01-01

    An apparatus and method for detecting alpha particles in the presence of high activities of beta particles utilizing an alpha spectrometer. The apparatus of the present invention utilizes a magnetic field applied around the sample in an alpha spectrometer to deflect the beta particles from the sample prior to reaching the detector, thus permitting detection of low concentrations of alpha particles. In the method of the invention, the strength of magnetic field required to adequately deflect the beta particles and permit alpha particle detection is given by an algorithm that controls the field strength as a function of sample beta energy and the distance of the sample to the detector.

  2. Alpha Particle Physics Experiments in the Tokamak Fusion Test Reactor

    SciTech Connect (OSTI)

    Budny, R.V.; Darrow, D.S.; Medley, S.S.; Nazikian, R.; Zweben, S.J.; et al.

    1998-12-14

    Alpha particle physics experiments were done on the Tokamak Fusion Test Reactor (TFTR) during its deuterium-tritium (DT) run from 1993-1997. These experiments utilized several new alpha particle diagnostics and hundreds of DT discharges to characterize the alpha particle confinement and wave-particle interactions. In general, the results from the alpha particle diagnostics agreed with the classical single-particle confinement model in magnetohydrodynamic (MHD) quiescent discharges. Also, the observed alpha particle interactions with sawteeth, toroidal Alfvén eigenmodes (TAE), and ion cyclotron resonant frequency (ICRF) waves were roughly consistent with theoretical modeling. This paper reviews what was learned and identifies what remains to be understood.

  3. Neutron Deficient Isotopes of Rhodium and Palladium

    E-Print Network [OSTI]

    Perlman, I.

    2010-01-01

    S OF RHODI U! \\~ AFD PALLADIUM by Manfred Lindner and I.Isotopes of B." odinm. and Palladium Hanfred Lindner and 1.i.a ABSTRACT A palladium activit;)r assigned to mass

  4. Atomic vapor laser isotope separation process

    DOE Patents [OSTI]

    Wyeth, R.W.; Paisner, J.A.; Story, T.

    1990-08-21

    A laser spectroscopy system is utilized in an atomic vapor laser isotope separation process. The system determines spectral components of an atomic vapor utilizing a laser heterodyne technique. 23 figs.

  5. Nonequilibrium clumped isotope signals in microbial methane

    E-Print Network [OSTI]

    Wang, David T.

    Methane is a key component in the global carbon cycle with a wide range of anthropogenic and natural sources. Although isotopic compositions of methane have traditionally aided source identification, the abundance of its ...

  6. A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER

    E-Print Network [OSTI]

    O'Donnell, Tom

    A SUPERCONDUCTING-SOLENOID ISOTOPE SPECTROMETER FOR PRODUCTION OF NEUTRON-RICH NUCLEI ( 136 Xe Superconducting Cyclotron Laboratory's weekly \\Green Sheet," 30 July 1999 #12; c Thomas W. O'Donnell 2000 All

  7. Photodisintegration of the isotope {sup 116}Cd

    SciTech Connect (OSTI)

    Belyshev, S. S.; Ishkhanov, B. S. [Moscow State University (Russian Federation)] [Moscow State University (Russian Federation); Orlin, V. N.; Stopani, K. A.; Khankin, V. V.; Shvedunov, N. V., E-mail: gg.swedn@gmail.com [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation)

    2013-08-15

    The results obtained by measuring the yields of photodisintegration of the isotope {sup 116}Cd irradiated with bremsstrahlung photons whose spectrum had an endpoint energy of 55 MeV are presented and compared with the results of theoretical calculations.

  8. The Isotopic Abundances of Magnesium in Stars

    E-Print Network [OSTI]

    Pamela Gay; David L. Lambert

    1999-11-11

    Isotopic abundance ratios 24^Mg:25^Mg:26^Mg are derived for 20 stars from high- resolution spectra of the MgH A-X 0-0 band at 5140AA. With the exception of the weak g-band giant HR 1299, the stars are dwarfs that sample the metallicity range -1.8 < [Fe/H] <0.0. The abundance of 25^Mg amd 26^Mg relative to the dominant isotope 24^Mg decreases with decreasing [Fe/H] in fair accord with predictions from a recent model of galactic chemical evolution in which the Mg isotopes are synthesised by massive stars. Several stars appear especially enriched in the heavier Mg isotopes suggesting contamination by material from the envelopes of intermediate-mass AGB stars.

  9. GEOL 715: STABLE ISOTOPE GEOCHEMISTRY (Spring, 2015)

    E-Print Network [OSTI]

    , nomenclature, standards -kinetic and equilibrium fractionation processes -mass and isotope budgets -Rayleigh in terrestrial plants and plankton -applications: carbon budgets, tracking anthropogenic CO2, carbon export rates sources, trophic levels, terrestrial vs marine sources 3. Recent advances: -mass independent fractionation

  10. The Giant Monopole Resonance in Pb isotopes

    E-Print Network [OSTI]

    Elias Khan

    2009-07-20

    The extraction of the nuclear incompressibility from the isoscalar giant monopole resonance (GMR) measurements is analysed. Both pairing and mutually enhanced magicity (MEM) effects play a role in the shift of the GMR energy between the doubly closed shell $^{208}$Pb nucleus and other Pb isotopes. Pairing effects are microscopically predicted whereas the MEM effect is phenomenologically evaluated. Accurate measurements of the GMR in open-shell Pb isotopes are called for.

  11. Probing surface distribution of $\\alpha$-cluster in $^{20}$Ne via $\\alpha$-transfer reaction

    E-Print Network [OSTI]

    Fukui, Tokuro; Suhara, Tadahiro; Kanada-En'yo, Yoshiko; Ogata, Kazuyuki

    2015-01-01

    Direct evidence of the $\\alpha$-cluster development in bound states has not been obtained yet although a number of experimental studies were carried out to extract the information of the clustering. In particular in conventional analyses of $\\alpha$-transfer reactions, there exist a few significant problems on reaction models, which are insufficient to qualitatively discuss the cluster structure. We aim to verify the development of the $\\alpha$-cluster structure from observables. As the first application, it is argued to extract the spatial information of the cluster structure of the $^{20}$Ne nucleus in its ground state through the cross section of the $\\alpha$-transfer reaction $^{16}$O($^6$Li,~$d$)$^{20}$Ne. For the analysis of the transfer reaction, we work with the coupled-channels Born approximation (CCBA) approach, in which the breakup effect of $^6$Li is explicitly taken into account by means of the continuum-discretized coupled-channels method (CDCC) based on the three-body $\\alpha + d + {}^{16}$O mo...

  12. Environmental assessment: special isotope separation process selection

    SciTech Connect (OSTI)

    Not Available

    1986-04-01

    This Environmental Assessment (EA) evaluates the differences in potential environmental impacts between two plutonium Special Isotope Separation (SIS) technologies: Atomic Vapor Laser Isotope Separation (AVLIS) and Molecular Laser Isotope Separation (MLIS). Both SIS technologies use PuO/sub 2/ as feed; AVLIS converts feed to plutonium metal and MLIS converts feed to PuF/sub 6/. The AVLIS process uses laser energy to selectively photoionize and electrostatically separate plutonium isotopes from an atomic vapor stream. The MLIS process uses laser energy to selectively disassociate specific isotopes of plutonium in the form of PuF/sub 6/ molecules to create PuF/sub 5/ for collection and further processing. Both processes produce plutonium metal as their product. An evaluation of differences in potential environmental impacts attributed to the construction of an SIS facility, based on either technology, included a comparison of construction materials, land areas required, and the size of the design and construction workforce. The differences in potential environmental impacts from operating an SIS facility were also compared. No large differences in potential environmental impacts would be expected from the use of process chemicals. An AVLIS or an MLIS facility would produce operating effluents that would meet all applicable radiation, chemical, and hazardous waste standards and would be constructed to protect workers, the public and the environment. This EA has not revealed any significant differences in the potential environmental impacts that could occur as a result of deploying either the AVLIS or the MLIS Special Isotope Separation technology.

  13. Radio Emitting Dust in the Free-Electron Layer of Spiral Galaxies: Testing the Disk/Halo Interface

    E-Print Network [OSTI]

    A. Ferrara; R. J. Dettmar

    1994-01-10

    We present a study of the radio emission from rotating, charged dust grains immersed in the ionized gas constituting the thick, H$\\alpha$-emitting disk of many spiral galaxies. Using up-to-date optical constants, the charge on the grains exposed to the diffuse galactic UV flux has been calculated. An analytical approximation for the grain charge has been derived, which is then used to obtain the grain rotation frequency. Grains are found to have substantial radio emission peaked at a cutoff frequency in the range 10-100~GHz, depending on the grain size distribution and on the efficiency of the radiative damping of the grain rotation. The dust radio emission is compared to the free-free emission from the ionized gas component; some constraints on the magnetic field strength in the observed dusty filaments are also discussed. The model can be used to test the disk-halo interface environment in spiral galaxies, to determine the amount and size distribution of dust in their ionized component, and to investigate the rotation mechanisms for the dust. Numerical estimates are given for experimental purposes.

  14. {alpha} decay and shape coexistence in the {alpha}-rotor model

    SciTech Connect (OSTI)

    Richards, J.D.; Bingham, C.R.; Nazarewicz, W.; Wauters, J.; Berggren, T.; Berggren, T.; Bingham, C.R.; Nazarewicz, W.; Nazarewicz, W.

    1997-09-01

    The particle-plus-rotor model was employed to study the fine structure seen in the {alpha} decay of even-even neutron-deficient nuclei in the Hg-Po region. The configuration mixing resulting from the shape coexistence between well-deformed prolate bands and spherical (or quasirotational oblate) structures in the daughter nuclei was considered. Experimental {alpha}-decay branching ratios are reproduced within one order of magnitude, except for the case of {sup 180}Hg, where the daughter nucleus {sup 176}Pt is expected to be triaxial in its ground state. The effect of configuration mixing on the relative intensities is discussed in detail, together with the sensitivity of results to the choice of the {alpha}-nucleus optical model parameters. {copyright} {ital 1997} {ital The American Physical Society}

  15. Bulk chemical and Hfâ??W isotopic consequences of incomplete accretion during planet formation

    E-Print Network [OSTI]

    Dwyer, Christina A; Nimmo, Francis; Chambers, John E

    2015-01-01

    Bulk chemical and Hf–W isotopic consequences of incompletestyle affects the bulk chemical and isotopic outcomes ofto investigate the bulk chemical and isotopic consequences

  16. COUPLING LEAD ISOTOPE ANALYSIS AND PETROGRAPHY TO CHARACTERIZE FABRICS OF STORAGE AND TRADE

    E-Print Network [OSTI]

    Claeys, Philippe

    COUPLING LEAD ISOTOPE ANALYSIS AND PETROGRAPHY TO CHARACTERIZE FABRICS OF STORAGE AND TRADE of petrography and lead isotopes within pottery provenance study. KEYWORDS: LEAD ISOTOPES, THIN SECTION, SHERD

  17. The 106Cd(alpha,alpha)106Cd elastic scattering in a wide energy range for gamma-process studies

    E-Print Network [OSTI]

    A. Ornelas; G. G. Kiss; P. Mohr; D. Galaviz; Zs. Fülöp; Gy. Gyürky; Z. Máté; T. Rauscher; E. Somorjai; K. Sonnabend; A. Zilges

    2015-04-29

    Alpha elastic scattering angular distributions of the 106Cd(alpha,alpha)106Cd reaction were measured at three energies around the Coulomb barrier to provide a sensitive test for the alpha + nucleus optical potential parameter sets. Furthermore, the new high precision angular distributions, together with the data available from the literature were used to study the energy dependence of the locally optimized {\\alpha}+nucleus optical potential in a wide energy region ranging from E_Lab = 27.0 MeV down to 16.1 MeV. The potentials under study are a basic prerequisite for the prediction of alpha-induced reaction cross sections and thus, for the calculation of stellar reaction rates used for the astrophysical gamma process. Therefore, statistical model predictions using as input the optical potentials discussed in the present work are compared to the available 106Cd + alpha cross section data.

  18. TRIFID (TRansuranic Isotopic Fraction Interrogation Device): A second generation plutonium isotopic analysis system

    SciTech Connect (OSTI)

    Fleissner, J G; Coressel, T W; Freier, D A; Macklin, L L

    1989-01-01

    The TRIFID (Transuranic Isotopic Fraction Interrogation Device) system is a second generation plutonium isotopic analysis system which incorporates many new and unique features in the area of isotopic data acquisition and isotopic analysis instrument consisting of a Canberra Series 95-MCA interfaced to a Compaq 386 computer. The entire TRIFID software package, including MCA communications and isotopic analysis routines, was developed using the C programming language. Extensive use has been made of user friendly screens and menus for ease of operation and training and to facilitate use by technical level operators. Automated TRIFID features provide for MCA/ADC setup and acquisition, spectral storage, isotopic analysis, and report generation. One unique feature of the TRIFID system design allows it to be pre-programed for an entire day's counting. The isotopic analysis module (EPICS) contains an expert system formalism which is used to detect and assay for spectral interferences, and to automatically adjust peak fitting constraints based on spectral intensity variations. A TRIFID system has been in operation in a production laboratory at the Rocky Flats Plant since September 1988. Marked decreases in training and hands-on operation time have been achieved in comparison to the older, preceding isotopic systems. 2 refs., 3 figs.

  19. Abbreviated MOVPE nucleation of III-nitride light-emitting diodes on nano-patterned sapphire

    E-Print Network [OSTI]

    Gilchrist, James F.

    -patterned AGOG sapphire demonstrated a 24% enhancement of output power enhancement over that of LEDs grown) light-emitting diodes (LEDs) on both templates were compared. The InGaN QWs LEDs grown on the nano- emitting diodes (LEDs) in solid state lighting applications [1 À11]. In conventional metalorganic vapor

  20. Proton implanted singlemode holey vertical-cavity surface-emitting lasers

    E-Print Network [OSTI]

    Choquette, Kent

    Proton implanted singlemode holey vertical-cavity surface-emitting lasers P.O. Leisher, A.J. Danner of proton implant confined vertical-cavity surface-emitting lasers. The index confinement and selective loss (both fundamental and non-fundamental) operation [9]. Although proton implantation for current

  1. Light extraction from organic light-emitting diodes for lighting applications by sand-blasting

    E-Print Network [OSTI]

    Light extraction from organic light-emitting diodes for lighting applications by sand@ust.hk Abstract: Light extraction from organic light-emitting diodes (OLEDs) by scattering the light is one of the effective methods for large-area lighting applications. In this paper, we present a very simple and cost

  2. Method to generate high efficient devices which emit high quality light for illumination

    DOE Patents [OSTI]

    Krummacher, Benjamin C. (Sunnyvale, CA); Mathai, Mathew (Santa Clara, CA); Choong, Vi-En (San Jose, CA); Choulis, Stelios A. (San Jose, CA)

    2009-06-30

    An electroluminescent apparatus includes an OLED device emitting light in the blue and green spectrums, and at least one down conversion layer. The down conversion layer absorbs at least part of the green spectrum light and emits light in at least one of the orange spectra and red spectra.

  3. Nanocluster-based white-light-emitting material employing surface tuning

    DOE Patents [OSTI]

    Wilcoxon, Jess P. (Albuquerque, NM); Abrams, Billie L. (Albuquerque, NM); Thoma, Steven G. (Albuquerque, NM)

    2007-06-26

    A method for making a nanocrystal-based material capable of emitting light over a sufficiently broad spectral range to appear white. Surface-modifying ligands are used to shift and broaden the emission of semiconductor nanocrystals to produce nanoparticle-based materials that emit white light.

  4. Light Extraction Efficiency and Radiation Patterns of III-Nitride Light-Emitting Diodes

    E-Print Network [OSTI]

    Gilchrist, James F.

    Light Extraction Efficiency and Radiation Patterns of III-Nitride Light-Emitting Diodes, IEEE DOI: 10.1109/JPHOT.2011.2150745 1943-0655/$26.00 ©2011 IEEE #12;Light Extraction Efficiency and Radiation Patterns of III-Nitride Light-Emitting Diodes With Colloidal Microlens Arrays With Various Aspect

  5. Efficiency improvement of phosphorescent organic light-emitting diodes using semitransparent Ag as anode

    E-Print Network [OSTI]

    Efficiency improvement of phosphorescent organic light-emitting diodes using semitransparent Ag The emission efficiency in an organic light-emitting diode OLED based on fac tris phenyl pyridine iridium Ir current efficiency of 81 cd/A and a power efficiency of 79 lm/W, compared with 46 cd/A and 39 lm

  6. Hydrocarbons emitted by waggle-dancing honey bees stimulate colony foraging activity by causing experienced

    E-Print Network [OSTI]

    Hydrocarbons emitted by waggle-dancing honey bees stimulate colony foraging activity by causing of the hydrocarbons emitted by waggle-dancing bees are investigated in this study. First, we test the hypothesis itself. waggle dance / cuticular hydrocarbon / nectar foraging / semiochemical / pheromone 1

  7. Reproducedwith pennissionfrom PNL V ARIANTS OF A LOW CO2-EMITTING

    E-Print Network [OSTI]

    ~-~--- Reproducedwith pennissionfrom PNL ~ V ARIANTS OF A LOW CO2-EMITTING ENERGY SUPPLY SYSTEM for the LESS Constructions 4 Constructing Alternative Low CO2-Emitting Energy Supply Systems 6 The Comparable variants of a Low Emissions Energy Supply System (LESS) for the World, which were presented in Section 3

  8. Genetic algorithms used for the optimization of light-emitting diodes and solar thermal collectors

    E-Print Network [OSTI]

    Mayer, Alexandre

    Genetic algorithms used for the optimization of light-emitting diodes and solar thermal collectors developed for the optimization of light-emitting diodes (LED) and solar thermal collectors. The surface a light-extraction efficiency of only 3.7%). The solar thermal collector we considered consists

  9. Efficient organic light-emitting diodes using polycrystalline silicon thin films as semitransparent anode

    E-Print Network [OSTI]

    .1063/1.2032604 Organic light-emitting diodes OLED have attracted much interest due to their potential application in flat with silicon microdisplay OLED.8,9 However, silicon has high absorption in the visible light which greatlyEfficient organic light-emitting diodes using polycrystalline silicon thin films as semitransparent

  10. Vanadium pentoxide modified polycrystalline silicon anode for active-matrix organic light-emitting diodes

    E-Print Network [OSTI]

    to be an efficient anode for organic light-emitting diode OLED X. L. Zhu, J. X. Sun, H. J. Peng, Z. G. Meng, M. Wong of Physics. DOI: 10.1063/1.2099520 Organic light-emitting diodes OLEDs have attracted wide attention dueVanadium pentoxide modified polycrystalline silicon anode for active-matrix organic light

  11. Fabrication of color tunable organic light-emitting diodes by an alignment free mask patterning method

    E-Print Network [OSTI]

    proposed for fabricating the side-by- side color tunable organic light-emitting diodes (OLEDs-voltage organic light emitting diodes (OLEDs) in 1987 [1], OLEDs have attracted much attention for the application of the white light OLEDs can be as high as 100 lm/W at a illumination level of 1000 cd/m2 [2], which is beyond

  12. Comparative study of metal or oxide capped indiumtin oxide anodes for organic light-emitting diodes

    E-Print Network [OSTI]

    of Physics. DOI: 10.1063/1.1556184 I. INTRODUCTION Organic light-emitting diodes OLEDs 1 are challengingComparative study of metal or oxide capped indium­tin oxide anodes for organic light as anodes in organic light-emitting diodes based on N,N -diphenyl-N,N bis 3-methyl-phenyl-1,1 -biphenyl-4

  13. White Light Emitting Diode Development for General Illumination Applications

    SciTech Connect (OSTI)

    James Ibbetson

    2006-05-01

    This report contains a summary of technical achievements during a 3-year project aimed at developing the chip and packaging technology necessary to demonstrate efficient, high flux light-emitting diode (LED) arrays using Cree's gallium nitride/silicon carbide (GaN/SiC) LED technology as the starting point. Novel chip designs and fabrication processes are described that led to high power blue LEDs that achieved 310 mW of light output at 350 mA drive current, corresponding to quantum and wall plug efficiencies of 32.5% and 26.5%, respectively. When combined with phosphor, high power white LEDs with luminous output of 67 lumens and efficacy of 57 lumens per watt were also demonstrated. Advances in packaging technology are described that enabled compact, multi-chip white LED lamp modules with 800-1000 lumens output at efficacies of up to 55 lumens per watt. Lamp modules with junction-to-ambient thermal resistance as low as 1.7 C/watt have also been demonstrated.

  14. Coincidence measurements between alpha particles and gamma rays in reactions induced by 85 and 155 MeV ¹²C on ¹??Sm 

    E-Print Network [OSTI]

    Cala, Steven Edward

    1978-01-01

    to fusion. Gamma rays in coincidence with the emitted alpha particles show that a fused system composed of the target plus the massive part of the projectile is produced. 12 In this work, 7. 1 and 12. 9 Nev/nucleon C beams incident on 154 Sm have been... in Reactions Induced by 85 and 155 NeV C on Sm. (August 1978) Steven Edward Cela, B. S. , Purdue University Chairmen of Advisory Committee: Prof. Thomas T. Sugihara A great deal has been learned about the compound nucleus and the fusion process by studying...

  15. Alpha resonant scattering for astrophysical reaction studies

    SciTech Connect (OSTI)

    Yamaguchi, H.; Kahl, D.; Nakao, T. [Center for Nuclear Study (CNS), University of Tokyo, RIKEN campus, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Wakabayashi, Y.; Kubano, S. [The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Hashimoto, T. [Research Center for Nuclear Physics (RCNP), Osaka University, 10-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Hayakawa, S. [Istituto Nazionale Fisica Nucleare - Laboratori Nazionali del Sud (INFN-LNS), Via S. Sofia 62, 95125 Catania (Italy); Kawabata, T. [Department of Physics, Kyoto University, Kita-Shirakawa, Kyoto 606-8502 (Japan); Iwasa, N. [Department of Physics, Tohoku University, Aoba, Sendai, Miyagi 980-8578 (Japan); Teranishi, T. [Department of Physics, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan); Kwon, Y. K. [Institute for Basic Science, 70, Yuseong-daero 1689-gil, Yuseong-gu, Daejeon 305-811 (Korea, Republic of); Binh, D. N. [30 MeV Cyclotron Center, Tran Hung Dao Hospital, Hoan Kiem District, Hanoi (Viet Nam); Khiem, L. H.; Duy, N. G. [Institute of Physics, Vietnam Academy of Science and Technology, 18 Hong Quoc Viet, Nghia do, Hanoi (Viet Nam)

    2014-05-02

    Several alpha-induced astrophysical reactions have been studied at CRIB (CNS Radioactive Ion Beam separator), which is a low-energy RI beam separator at Center for Nuclear Study (CNS) of the University of Tokyo. One of the methods to study them is the ? resonant scattering using the thick-target method in inverse kinematics. Among the recent studies at CRIB, the measurement of {sup 7}Be+? resonant scattering is discussed. Based on the result of the experiment, we evaluated the contributions of high-lying resonances for the {sup 7}Be(?,?) reaction, and proposed a new cluster band in {sup 11}C.

  16. Resolving the stellar sources of isotopically rare presolar silicate grains through Mg and Fe isotopic analyses

    SciTech Connect (OSTI)

    Nguyen, Ann N.; Messenger, Scott, E-mail: lan-anh.n.nguyen@nasa.gov [Robert M. Walker Laboratory for Space Science, Astromaterials Research and Exploration Science Directorate, NASA Johnson Space Center, Houston, TX 77058 (United States)

    2014-04-01

    We conducted multi-element isotopic analyses of 11 presolar silicate grains from the Acfer 094 meteorite having unusual O isotopic compositions. Eight grains are {sup 18}O-rich, one is {sup 16}O-rich, and two are extremely {sup 17}O-rich. We constrained the grains' stellar sources by measuring their Si and Mg isotopic ratios, and also the {sup 54}Fe/{sup 56}Fe and {sup 57}Fe/{sup 56}Fe ratios for five grains. The Mg and Fe isotopic measurements were conducted after surrounding matrix grains were removed for more accurate ratios. Most of the {sup 18}O-rich silicates had anomalous Mg isotopic ratios, and their combined isotopic constraints are consistent with origins in low-mass Type II supernovae (SNe II) rather than high-metallicity stars. The isotopic ratios of the {sup 16}O-rich silicate are also consistent with an SN origin. Mixing small amounts of interior stellar material with the stellar envelope replicated all measured isotopic ratios except for {sup 29}Si/{sup 28}Si and {sup 54}Fe/{sup 56}Fe in some grains. The {sup 29}Si/{sup 28}Si ratios of all SN-derived grains are matched by doubling the {sup 29}Si yield in the Ne- and Si-burning zones. The {sup 54}Fe/{sup 56}Fe ratios of the grains imply elemental fractionation in the Si/S zone, or introduction of isotopically solar Fe by secondary processing. The two highly {sup 17}O-rich silicates exhibited significant {sup 25}Mg and/or {sup 26}Mg enrichments and their isotopic ratios are best explained by strong dilution of 1.15 M {sub ?} CO nova matter. We estimate that ?12% and 1% of presolar silicates have SN and nova origins, respectively, similar to presolar SiC and oxides. This implies that asymptotic giant branch stars are the dominant dust producers in the galaxy.

  17. Laser Isotope Separation Employing Condensation Repression

    SciTech Connect (OSTI)

    Eerkens, Jeff W.; Miller, William H.

    2004-09-15

    Molecular laser isotope separation (MLIS) techniques using condensation repression (CR) harvesting are reviewed and compared with atomic vapor laser isotope separation (AVLIS), gaseous diffusion (DIF), ultracentrifuges (UCF), and electromagnetic separations (EMS). Two different CR-MLIS or CRISLA (Condensation Repression Isotope Separation by Laser Activation) approaches have been under investigation at the University of Missouri (MU), one involving supersonic super-cooled free jets and dimer formation, and the other subsonic cold-wall condensation. Both employ mixtures of an isotopomer (e.g. {sup i}QF{sub 6}) and a carrier gas, operated at low temperatures and pressures. Present theories of VT relaxation, dimerization, and condensation are found to be unsatisfactory to explain/predict experimental CRISLA results. They were replaced by fundamentally new models that allow ab-initio calculation of isotope enrichments and predictions of condensation parameters for laser-excited and non-excited vapors which are in good agreement with experiment. Because of supersonic speeds, throughputs for free-jet CRISLA are a thousand times higher than cold-wall CRISLA schemes, and thus preferred for large-quantity Uranium enrichments. For small-quantity separations of (radioactive) medical isotopes, the simpler coldwall CRISLA method may be adequate.

  18. Performance checks with the Alpha Sentry CAM

    SciTech Connect (OSTI)

    Rodgers, J.C.

    1994-08-01

    Before a CAM is put into service, it must be calibrated. The flow meter and detector must be calibrated with an external flow meter to provide accurate flow data, and the detector must be calibrated to produce accurate DPM data. Both flow and DPM data enter into the calculation of the Derived Air Concentration exposure (DAC-hr) by the CAM software. The focus of this report is on methods for checking that the DAC-hr alarm functionality has been properly calibrated and available in installed CAM instruments. The process begins with detector calibration. In order to calibrate the detector, the Alpha Sentry CAM is placed in an off-line calibration mode and detector efficiency calibration is selected. The user is prompted to enter the calibration source DPM and place the source in the CAM head. Upon latching the filter door with the source in place, a count is automatically initiated and completed. From the count data and the user entered DPM data, an efficiency is determined in the Alpha Sentry Manager (ASM) and stored in non-volatile memory in the CAM head electronics. This source is typically a plated {sup 239}Pu or {sup 241}Am source diffused into a stainless steel planchet.

  19. GHRS Observations of the Lyman alpha Forest

    E-Print Network [OSTI]

    Simon L. Morris

    1996-10-28

    I review the results obtained using the GHRS on low redshift Lyman alpha absorbers. Until the advent of HST and the GHRS, the existence of such absorbers was doubted. The confirmation of their existence, in one of the first GHRS GTO team results to be published, must rank as one of the HSTs most interesting results. The GHRS resolution allows us to probe equivalent widths well below those detectable with the FOS, and has led to a number of interesting new questions. One example is the apparent disagreement between the GHRS result that there are many Lyman alpha absorbers which are not associated with luminous galaxies, and FOS studies which suggest that all such absorbers have a nearby galaxy causing them. This almost certainly shows that the equivalent width (or column density) range reachable by the GHRS includes gas from a wide range of causes, and not only the halos of luminous galaxies. With these data, we are seeing the debris left over from Galaxy formation, material flung out from galaxy interactions and starbursts, and also diffuse halo material at the outer edges of normal galaxies.

  20. MFTF-. cap alpha. + T progress report

    SciTech Connect (OSTI)

    Nelson, W.D.

    1985-04-01

    Early in FY 1983, several upgrades of the Mirror Fusion Test Facility (MFTF-B) at Lawrence Livermore National Laboratory (LLNL) were proposed to the fusion community. The one most favorably received was designated MFTF-..cap alpha..+T. The engineering design of this device, guided by LLNL, has been a principal activity of the Fusion Engineering Design Center during FY 1983. This interim progress report represents a snapshot of the device design, which was begun in FY 1983 and will continue for several years. The report is organized as a complete design description. Because it is an interim report, some parts are incomplete; they will be supplied as the design study proceeds. As described in this report, MFTF-..cap alpha..+T uses existing facilities, many MFTF-B components, and a number of innovations to improve on the physics parameters of MFTF-B. It burns deuterium-tritium and has a central-cell Q of 2, a wall loading GAMMA/sub n/ of 2 MW/m/sup 2/ (with a central-cell insert module), and an availability of 10%. The machine is fully shielded, allows hands-on maintenance of components outside the vacuum vessel 24 h after shutdown, and has provisions for repair of all operating components.

  1. Lyman alpha Absorption Systems and the Intergalactic Medium

    E-Print Network [OSTI]

    George Efstathiou; Joop Schaye; Tom Theuns

    2000-04-10

    The last few years have seen a dramatic improvement in our understanding of the origin of Lyman alpha absorption systems. Hydrodynamic numerical simulations of cold dark matter dominated universes have shown that the many properties of the Lyman alpha absorption systems can be explained by a photoionized, space-filling, intergalactic medium. Lyman alpha lines offer promising probes of the photoionizing background, the amplitude of the mass fluctuations at high redshift and the evolution of the equation of state of the intergalactic medium.

  2. Overview of the U.S. Department of Energy's Isotope Programs

    SciTech Connect (OSTI)

    Carty, J.

    2004-10-05

    This presentation provides an overview of the U.S. Department of Energy's Isotopes Program. The charter of the Isotope Programs covers the production and sale of radioactive and stable isotopes, associated byproducts, surplus materials, and related isotope services.

  3. Carbonitride based phosphors and light emitting devices using the same

    DOE Patents [OSTI]

    Li, Yuanqiang; Tian, Yongchi; Romanelli, Michael Dennis

    2013-08-20

    Disclosed herein is a novel group of carbidonitride phosphors and light emitting devices which utilize these phosphors. In certain embodiments, the present invention is directed to a novel family of carbidonitride-based phosphors expressed as follows: Ca.sub.1-xAl.sub.x-xySi.sub.1-x+xyN.sub.2-x-xyC.sub.xy:A; (1) Ca.sub.1-x-zNa.sub.zM(III).sub.x-xy-zSi.sub.1-x+xy+zN.sub.2-x-xyC.sub.xy:- A; (2) M(II).sub.1-x-zM(I).sub.zM(III).sub.x-xy-zSi.sub.1-x+xy+zN.sub.2-x- -xyC.sub.xy:A; (3) M(II).sub.1-x-zM(I).sub.zM(III).sub.x-xy-zSi.sub.1-x+xy+zN.sub.2-x-xy-2w/- 3C.sub.xyO.sub.w-v/2H.sub.v:A; and (4) M(II).sub.1-x-zM(I).sub.zM(III).sub.x-xy-zSi.sub.1-x+xy+zN.sub.2-x-xy-2w/- 3-v/3C.sub.xyO.sub.wH.sub.v:A, (4a) wherein 0xy+z, and 0

  4. Two- and three-alpha systems with nonlocal potential

    E-Print Network [OSTI]

    Z. Papp; S. Moszkowski

    2008-03-26

    Two body data alone cannot determine the potential uniquely, one needs three-body data as well. A method is presented here which simultaneously fits local or nonlocal potentials to two-body and three-body observables. The interaction of composite particles, due to the Pauli effect and the indistinguishability of the constituent particles, is genuinely nonlocal. As an example, we use a Pauli-correct nonlocal fish-bone type optical model for the $\\alpha-\\alpha$ potential and derive the fitting parameters such that it reproduces the two-$\\alpha$ and three-$\\alpha$ experimental data.

  5. Penguin pollution estimates relevant for phi_2/alpha extraction

    E-Print Network [OSTI]

    Jure Zupan

    2007-08-16

    A review of methods to extract the standard CKM unitarity triangle angle alpha is provided. The sizes of related theoretical errors are reviewed.

  6. Alpha-particle optical potential proofs at astrophysically relevant energies

    E-Print Network [OSTI]

    M. Avrigeanu; V. Avrigeanu

    2008-11-01

    $(\\alpha,\\gamma)$ and $(\\alpha$,n) reaction cross sections recently measured close to the reaction thresholds are rather well described by a previously developed regional optical potential. Thus, particular features of the $\\alpha$-particle optical potential at energies below the Coulomb barrier, besides parameters describing $\\alpha$-particle elastic scattering at higher energies are confirmed. Additional limitations of similar statistical model calculations for minor reaction channels are shown to be most likely due to an overlooked process or critical values of statistical model parameters around closed nuclear shells.

  7. Sieving hydrogen isotopes through two dimensional crystals

    E-Print Network [OSTI]

    M. Lozada-Hidalgo; S. Hu; O. Marshall; A. Mishchenko; A. N. Grigorenko; R. A. W. Dryfe; B. Radha; I. V. Grigorieva; A. K. Geim

    2015-11-20

    One-atom-thick crystals are impermeable to atoms and molecules, but hydrogen ions (thermal protons) penetrate through them. We show that monolayers of graphene and boron nitride can be used to separate hydrogen ion isotopes. Employing electrical measurements and mass spectrometry, we find that deuterons permeate through these crystals much slower than protons, resulting in a separation factor of 10 at room temperature. The isotope effect is attributed to a difference of about 60 meV between zero-point energies of incident protons and deuterons, which translates into the equivalent difference in the activation barriers posed by two dimensional crystals. In addition to providing insight into the proton transport mechanism, the demonstrated approach offers a competitive and scalable way for hydrogen isotope enrichment.

  8. Apparatus for separating and recovering hydrogen isotopes

    DOE Patents [OSTI]

    Heung, Leung K. (Aiken, SC)

    1994-01-01

    An apparatus for recovering hydrogen and separating its isotopes. The apparatus includes a housing bearing at least a fluid inlet and a fluid outlet. A baffle is disposed within the housing, attached thereto by a bracket. A hollow conduit is coiled about the baffle, in spaced relation to the baffle and the housing. The coiled conduit is at least partially filled with a hydride. The hydride can be heated to a high temperature and cooled to a low temperature quickly by circulating a heat transfer fluid in the housing. The spacing between the baffle and the housing maximizes the heat exchange rate between the fluid in the housing and the hydride in the conduit. The apparatus can be used to recover hydrogen isotopes (protium, deuterium and tritium) from gaseous mixtures, or to separate hydrogen isotopes from each other.

  9. Sieving hydrogen isotopes through two dimensional crystals

    E-Print Network [OSTI]

    Lozada-Hidalgo, M; Marshall, O; Mishchenko, A; Grigorenko, A N; Dryfe, R A W; Radha, B; Grigorieva, I V; Geim, A K

    2015-01-01

    One-atom-thick crystals are impermeable to atoms and molecules, but hydrogen ions (thermal protons) penetrate through them. We show that monolayers of graphene and boron nitride can be used to separate hydrogen ion isotopes. Employing electrical measurements and mass spectrometry, we find that deuterons permeate through these crystals much slower than protons, resulting in a separation factor of 10 at room temperature. The isotope effect is attributed to a difference of about 60 meV between zero-point energies of incident protons and deuterons, which translates into the equivalent difference in the activation barriers posed by two dimensional crystals. In addition to providing insight into the proton transport mechanism, the demonstrated approach offers a competitive and scalable way for hydrogen isotope enrichment.

  10. Diffusion in silicon isotope heterostructures

    SciTech Connect (OSTI)

    Silvestri, Hughes Howland

    2004-05-14

    The simultaneous diffusion of Si and the dopants B, P, and As has been studied by the use of a multilayer structure of isotopically enriched Si. This structure, consisting of 5 pairs of 120 nm thick natural Si and {sup 28}Si enriched layers, enables the observation of {sup 30}Si self-diffusion from the natural layers into the {sup 28}Si enriched layers, as well as dopant diffusion from an implanted source in an amorphous Si cap layer, via Secondary Ion Mass Spectrometry (SIMS). The dopant diffusion created regions of the multilayer structure that were extrinsic at the diffusion temperatures. In these regions, the Fermi level shift due to the extrinsic condition altered the concentration and charge state of the native defects involved in the diffusion process, which affected the dopant and self-diffusion. The simultaneously recorded diffusion profiles enabled the modeling of the coupled dopant and self-diffusion. From the modeling of the simultaneous diffusion, the dopant diffusion mechanisms, the native defect charge states, and the self- and dopant diffusion coefficients can be determined. This information is necessary to enhance the physical modeling of dopant diffusion in Si. It is of particular interest to the modeling of future electronic Si devices, where the nanometer-scale features have created the need for precise physical models of atomic diffusion in Si. The modeling of the experimental profiles of simultaneous diffusion of B and Si under p-type extrinsic conditions revealed that both species are mediated by neutral and singly, positively charged Si self-interstitials. The diffusion of As and Si under extrinsic n-type conditions yielded a model consisting of the interstitialcy and vacancy mechanisms of diffusion via singly negatively charged self-interstitials and neutral vacancies. The simultaneous diffusion of P and Si has been modeled on the basis of neutral and singly negatively charged self-interstitials and neutral and singly positively charged P species. Additionally, the temperature dependence of the diffusion coefficient of Si in Ge was measured over the temperature range of 550 C to 900 C using a buried Si layer in an epitaxially grown Ge layer.

  11. Organic light emitting device architecture for reducing the number of organic materials

    DOE Patents [OSTI]

    D'Andrade, Brian (Westampton, NJ); Esler, James (Levittown, PA)

    2011-10-18

    An organic light emitting device is provided. The device includes an anode and a cathode. A first emissive layer is disposed between the anode and the cathode. The first emissive layer includes a first non-emitting organic material, which is an organometallic material present in the first emissive layer in a concentration of at least 50 wt %. The first emissive layer also includes a first emitting organic material. A second emissive layer is disposed between the first emissive layer and the cathode, preferably, in direct contact with the first emissive layer. The second emissive material includes a second non-emitting organic material and a second emitting organic material. The first and second non-emitting materials, and the first and second emitting materials, are all different materials. A first non-emissive layer is disposed between the first emissive layer and the anode, and in direct contact with the first emissive layer. The first non- emissive layer comprises the first non-emissive organic material.

  12. PHYSICAL, MAGNETIC, SEDIMENTOLOGICAL, GEOCHEMICAL, ISOTOPIC AND MICROPALEONTOLOGICAL FEATURES OF RAPIDLY DEPOSITED

    E-Print Network [OSTI]

    PHYSICAL, MAGNETIC, SEDIMENTOLOGICAL, GEOCHEMICAL, ISOTOPIC AND MICROPALEONTOLOGICAL FEATURES Sediments, Québec City. Symposium preceedings: 103-108. ABSTRACT: Sedimentological, geochemical, isotopic

  13. Method for production of an isotopically enriched compound

    DOE Patents [OSTI]

    Watrous, Matthew G.

    2012-12-11

    A method is presented for producing and isolating an isotopically enriched compound of a desired isotope from a parent radionuclide. The method includes forming, or placing, a precipitate containing a parent radionuclide of the desired daughter isotope in a first reaction zone and allowing sufficient time for the parent to decay into the desired gaseous daughter radioisotope. The method further contemplates collecting the desired daughter isotope as a solid in a second reaction zone through the application of temperatures below the freezing point of the desired isotope to a second reaction zone that is connected to the first reaction zone. Specifically, a method is presented for producing isotopically enriched compounds of xenon, including the radioactive isotope Xe-131m and the stable isotope Xe-131.

  14. Isotope and Temperature Effects in Liquid Water Probed by Soft...

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

    Isotope and Temperature Effects in Liquid Water Probed by Soft X Rays Isotope and Temperature Effects in Liquid Water Probed by Soft X Rays Print Wednesday, 24 September 2008 00:00...

  15. Oxygen isotope records of carboniferous seasonality on the Russian platform 

    E-Print Network [OSTI]

    Wang, Huayu

    1998-01-01

    Seven isotopic and eight trace element (TE) profiles across shell growth lines are presented, based on over 1000 stable isotope and electron microprobe analyses on six brachiopod shells (Gigantoproductus), to quantify seasonal temperature change...

  16. Physiology of multiple sulfur isotope fractionation during microbial sulfate reduction

    E-Print Network [OSTI]

    Sim, Min Sub

    2012-01-01

    Microbial sulfate reduction (MSR) utilizes sulfate as an electron acceptor and produces sulfide that is depleted in heavy isotopes of sulfur relative to starting sulfate. The fractionation of S-isotopes is commonly used ...

  17. Hydrogen isotope fractionation during lipid biosynthesis by Haloarcula marismortui

    E-Print Network [OSTI]

    Hydrogen isotope fractionation during lipid biosynthesis by Haloarcula marismortui Sitindra S studied the controls on the fractionation of hydrogen isotopes during lipid biosynthesis by Haloarcula marismortui, a halophilic archaea, in pure culture experiments by varying organic substrate, the hydrogen

  18. Isotopic abundance in atom trap trace analysis

    DOE Patents [OSTI]

    Lu, Zheng-Tian; Hu, Shiu-Ming; Jiang, Wei; Mueller, Peter

    2014-03-18

    A method and system for detecting ratios and amounts of isotopes of noble gases. The method and system is constructed to be able to measure noble gas isotopes in water and ice, which helps reveal the geological age of the samples and understand their movements. The method and system uses a combination of a cooled discharge source, a beam collimator, a beam slower and magneto-optic trap with a laser to apply resonance frequency energy to the noble gas to be quenched and detected.

  19. Coherent photonuclear reactions for isotope transmutation

    E-Print Network [OSTI]

    H. Ejiri; S. Date

    2011-02-22

    Coherent photonuclear isotope transmutation (CPIT) produces exclusively radioactive isotopes (RIs) by coherent photonuclear reactions via E1 giant resonances. Photons to be used are medium energy photons produced by laser photons backscattered off GeV electrons. The cross sections are as large as 0.2 - 0.6 b, being independent of individual nuclides. A large fraction of photons is effectively used for the photonuclear reactions, while the scattered GeV electrons remain in the storage ring to be re-used. CPIT with medium energy photons provides specific/desired RIs with the high rate and the high density for nuclear science, molecular biology and for nuclear medicines.

  20. Stable carbon and nitrogen isotope enrichment in primate tissues

    E-Print Network [OSTI]

    Crowley, Brooke E.; Carter, Melinda L.; Karpanty, Sarah M.; Zihlman, Adrienne L.; Koch, Paul L.; Dominy, Nathaniel J.

    2010-01-01

    of sample treatment and diagenesis on the isotopic integrityHare PE (1986) Effects of diagenesis on strontium, carbon,

  1. High efficiency and brightness fluorescent organic light emitting diode by triplet-triplet fusion

    DOE Patents [OSTI]

    Forrest, Stephen; Zhang, Yifan

    2015-02-10

    A first device is provided. The first device further comprises an organic light emitting device. The organic light emitting device further comprises an anode, a cathode, and an emissive layer disposed between the anode and the cathode. The emissive layer may include an organic host compound and at least one organic emitting compound capable of fluorescent emission at room temperature. Various configurations are described for providing a range of current densities in which T-T fusion dominates over S-T annihilation, leading to very high efficiency fluorescent OLEDs.

  2. Discovery of palladium, antimony, tellurium, iodine, and xenon isotopes

    E-Print Network [OSTI]

    J. Kathawa; C. Fry; M. Thoennessen

    2012-01-20

    Currently, thirty-eight palladium, thirty-eight antimony, thirty-nine tellurium, thirty-eight iodine, and forty xenon isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  3. Discovery of palladium, antimony, tellurium, iodine, and xenon isotopes

    SciTech Connect (OSTI)

    Kathawa, J.; Fry, C.; Thoennessen, M., E-mail: thoennessen@nscl.msu.edu

    2013-01-15

    Currently, thirty-eight palladium, thirty-eight antimony, thirty-nine tellurium, thirty-eight iodine, and forty xenon isotopes have been observed and the discovery of these isotopes is described here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  4. Discovery of Cesium, Lanthanum, Praseodymium and Promethium Isotopes

    E-Print Network [OSTI]

    E. May; M. Thoennessen

    2011-09-08

    Currently, forty-one cesium, thirty-five lanthanum, thirty-two praseodymium, and thirty-one promethium, isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  5. Hydrogen isotope fractionation during lipid biosynthesis by Tetrahymena thermophila

    E-Print Network [OSTI]

    Hydrogen isotope fractionation during lipid biosynthesis by Tetrahymena thermophila Sitindra S Accepted 7 September 2013 Available online 16 September 2013 a b s t r a c t Hydrogen isotope ratio values from recording the hydrogen isotope composition of ambient water, dD values of lipids also depend

  6. Discovery of Gallium, Germanium, Lutetium, and Hafnium Isotopes

    E-Print Network [OSTI]

    Gross, J L

    2011-01-01

    Currently, twenty-eight gallium, thirty-one germanium, thirty-five lutetium, and thirty-six hafnium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  7. Discovery of Gallium, Germanium, Lutetium, and Hafnium Isotopes

    E-Print Network [OSTI]

    J. L. Gross; M. Thoennessen

    2011-09-28

    Currently, twenty-eight gallium, thirty-one germanium, thirty-five lutetium, and thirty-six hafnium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  8. Discovery of the actinium, thorium, protactinium, and uranium isotopes

    E-Print Network [OSTI]

    C. Fry; M. Thoennessen

    2012-03-06

    Currently, 31 actinium, 31 thorium, 28 protactinium, and 23 uranium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  9. Evidence of magnetic isotope effects during thermochemical sulfate reduction

    E-Print Network [OSTI]

    Kaufman, Alan Jay

    such as adsorption of S-bearing com- pounds on surfaces of solids (13). Magnetic isotope effects are expressedEvidence of magnetic isotope effects during thermochemical sulfate reduction Harry Oduroa,b,1 S are attributed to a magnetic isotope effect (MIE) associated with the formation of thiol-disulfide, ion

  10. Discovery of Yttrium, Zirconium, Niobium, Technetium, and Ruthenium Isotopes

    E-Print Network [OSTI]

    A. Nystrom; M. Thoennessen

    2011-02-11

    Currently, thirty-four yttrium, thirty-five zirconium, thirty-four niobium, thirty-five technetium, and thirty-eight ruthenium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  11. Discovery of Yttrium, Zirconium, Niobium, Technetium, and Ruthenium Isotopes

    E-Print Network [OSTI]

    Nystrom, A

    2011-01-01

    Currently, thirty-four yttrium, thirty-five zirconium, thirty-four niobium, thirty-five technetium, and thirty-eight ruthenium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  12. E.L. Grossman Chapter 10 Oxygen Isotope Stratigraphy

    E-Print Network [OSTI]

    Grossman, Ethan L.

    E.L. Grossman Chapter 10 Oxygen Isotope Stratigraphy Abstract:Variations in the 18 O/16 O ratios isotope stratigraphy, however, is hampered by the lack of unaltered authigenic marine sediments. Chapter.6. Oxygen Isotope Stratigraphy 188 10.6.1. Cenozoic 188 10.6.2. Mesozoic 191 10.6.3. Paleozoic 193

  13. Discovery of Samarium, Europium, Gadolinium, and Terbium Isotopes

    E-Print Network [OSTI]

    E. May; M. Thoennessen

    2012-01-19

    Currently, thirty-four samarium, thirty-four europium, thirty-one gadolinium, and thirty-one terbium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  14. Discovery of the astatine, radon, francium, and radium isotopes

    E-Print Network [OSTI]

    C. Fry; M. Thoennessen

    2012-05-26

    Currently, thirty-nine astatine, thirty-nine radon, thirty-five francium, and thirty-four radium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  15. Discovery of the thallium, lead, bismuth, and polonium isotopes

    E-Print Network [OSTI]

    C. Fry; M. Thoennessen

    2012-01-21

    Currently, forty-two thallium, forty-two lead, forty-one bismuth, and forty-two polonium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  16. Discovery of dysprosium, holmium, erbium, thulium and ytterbium isotopes

    E-Print Network [OSTI]

    C. Fry; M. Thoennessen

    2012-05-26

    Currently, 31 dysprosium, 32 holmium, 32 erbium, 33 thulium and 31 ytterbium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  17. Discovery of Tantalum, Rhenium, Osmium, and Iridium Isotopes

    E-Print Network [OSTI]

    R. Robinson; M. Thoennessen

    2011-09-02

    Currently, thirty-eight tantalum, thirty-eight rhenium, thirty-nine osmium, and thirty-eight iridium, isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  18. 4.2: Design of an Improved Pixel for a Polysilicon Active Matrix Organic Light Emitting Diode Display

    E-Print Network [OSTI]

    4.2: Design of an Improved Pixel for a Polysilicon Active Matrix Organic Light Emitting Diode active matrix organic light emitting diode (AMOLED) pixel with high pixel to pixel luminance uniformity such as organic light emitting diodes (OLEDs) are presently of great interest due to their potential application

  19. Intramolecular excimer emission as a blue light source in fluorescent organic light emitting diodes: a promising molecular design

    E-Print Network [OSTI]

    Boyer, Edmond

    Intramolecular excimer emission as a blue light source in fluorescent organic light emitting diodes Light Emitting Diode (OLED), intermolecular p­p interactions should be usually suppressed to avoid any Emitting Diodes (SMOLEDs) is almost absent from the literature. In this work, three aryl-substituted Di

  20. Journal of Crystal Growth 298 (2007) 272275 Dislocation analysis in homoepitaxial GaInN/GaN light emitting

    E-Print Network [OSTI]

    Wetzel, Christian M.

    2007-01-01

    of GaInN/GaN-based light emitting diodes (LED) on quasi-bulk GaN with an atomically flat polished were much improved. The optical output power of the light emitting diode increased by more than one. Cathodoluminescence; A1. Threading dislocation density; A2. Homoepitaxial growth; B1. GaInN; B3. Light emitting diode

  1. Vacuum-free lamination of low work function cathode for efficient solution-processed organic light-emitting diodes

    E-Print Network [OSTI]

    Meng, Hsin-Fei

    -coated organic light-emitting diode is transferred from a soft polydimethylsiloxane (PDMS) mold by lamination, or blade coating [1,2] for organic light emitting diode (OLED) as well as solar cell. The top electrodeVacuum-free lamination of low work function cathode for efficient solution-processed organic light-emitting

  2. Junction temperature, spectral shift, and efficiency in GaInN-based blue and green light emitting diodes

    E-Print Network [OSTI]

    Wetzel, Christian M.

    Keywords: GaInN/GaN Light emitting diode temperature Micro-Raman Photoluminescence Electroluminescence well light emitting diode (LED) dies is analyzed by micro-Raman, photoluminescence, cathodoluminescenceJunction temperature, spectral shift, and efficiency in GaInN-based blue and green light emitting

  3. Wavelength-resolved low-frequency noise of GaInN/GaN green light emitting diodes

    E-Print Network [OSTI]

    Wetzel, Christian M.

    Wavelength-resolved low-frequency noise of GaInN/GaN green light emitting diodes S. L. Rumyantseva well light emitting diodes. The light intensity noise was measured as a function of wavelength within the light emitting diode spectral emission line. The spectral noise density is found to increase

  4. Thickness-dependent changes in the optical properties of PPV-and PF-based polymer light emitting diodes

    E-Print Network [OSTI]

    Carter, Sue

    the thickness-dependent optical properties of single layer polymer light emitting diodes for two materials, poly the electronic and optical properties of these materials in light emitting diode LED structures.2 OurThickness-dependent changes in the optical properties of PPV- and PF-based polymer light emitting

  5. Enhanced hole injection in a polymer light emitting diode using a small molecule monolayer bound to the anode

    E-Print Network [OSTI]

    Schwartz, Jeffrey

    Enhanced hole injection in a polymer light emitting diode using a small molecule monolayer bound of modern display technologies [1]. A simple polymer light emitting diode (PLED) can be constructed-naphthyl)-N,N0 -diphenyl1- 1,1-biphenyl1-4, 40 -diamine (a-NPD) in light emitting diode devices [14

  6. High-density organic light emitting diodes by nanoimprint technology Krutarth Trivedi, Caleb Nelson, Li Tao, Mathew Goeckner, Walter Hua)

    E-Print Network [OSTI]

    Hu, Wenchuang "Walter"

    High-density organic light emitting diodes by nanoimprint technology Krutarth Trivedi, Caleb Nelson sources. Despite the considerable development of inorganic semiconductor based light emitting diodes of miniaturization to nanoscale. Organic light emitting diode (OLED) technology is immune to quantum confinement

  7. Efficiency enhancement in a light-emitting diode with a two-dimensional surface grating photonic crystal

    E-Print Network [OSTI]

    Baba, Toshihiko

    Efficiency enhancement in a light-emitting diode with a two-dimensional surface grating photonic 21 November 2003 We demonstrate a light-emitting diode exhibiting 1.7­2.7-fold enhancement in light light emitting diode LED , the ef- ficiency is limited to several percents by a low light extrac- tion

  8. Polarization engineering via staggered InGaN quantum wells for radiative efficiency enhancement of light emitting diodes

    E-Print Network [OSTI]

    Gilchrist, James F.

    of light emitting diodes Ronald A. Arif, Yik-Khoon Ee, and Nelson Tansu Citation: Appl. Phys. Lett. 91 extraction in GaN-based light emitting diodes Appl. Phys. Lett. 100, 061107 (2012) Electrically driven nanopyramid green light emitting diode Appl. Phys. Lett. 100, 061106 (2012) Ultraviolet electroluminescence

  9. Enhanced emission efficiency in organic light-emitting diodes using deoxyribonucleic acid complex as an electron blocking layer

    E-Print Network [OSTI]

    Cincinnati, University of

    as an integral element of organic light-emitting diodes OLED . Devices that incorporate DNA thin films#12;Enhanced emission efficiency in organic light-emitting diodes using deoxyribonucleic acid as an electron blocking EB material has been demonstrated in both green- and blue-emitting organic light

  10. AC-driven, color-and brightness-tunable organic light-emitting diodes constructed from an electron only device

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    - and brightness-tunable organic light-emitting diode (OLED) is reported. This OLED was realized by inserting emission from an organic light- emitting diode (OLED) [1] results from the electron/hole recombinationAC-driven, color- and brightness-tunable organic light-emitting diodes constructed from an electron

  11. Using a low-index host layer to increase emission from organic light-emitting diode structures

    E-Print Network [OSTI]

    Exeter, University of

    The out-coupling efficiency of organic light-emitting diodes (OLEDs) may be significantly increased by use.60.Jb; 72.80.Le Keywords: Organic light-emitting diode (OLED); Out-coupling efficiency; Refractive index organic light-emitting diodes (OLEDs), with a large amount of this work centring on the efficiency

  12. Optoelectronic properties of poly(fluorene) co-polymer light-emitting devices on a plastic substrate*

    E-Print Network [OSTI]

    Kanicki, Jerzy

    displays. Thus far, most of the organic light-emitting device (OLED) displays are fabri- cated on rigidOptoelectronic properties of poly(fluorene) co-polymer light-emitting devices on a plastic of red, green, and blue poly(fluorene) co-polymer light- emitting devices (PLEDs) on a plastic substrate

  13. Direct nanoimprint of submicron organic light-emitting structures Jian Wang, Xiaoyun Sun, Lei Chen, and Stephen Y. Choua)

    E-Print Network [OSTI]

    light-emitting diodes OLED , organic flat panel dis- plays, and organic lasers have been under intensiveDirect nanoimprint of submicron organic light-emitting structures Jian Wang, Xiaoyun Sun, Lei Chen demonstrated a method to directly pattern organic light-emitting structures with a submicron resolution without

  14. Lyman Alpha Absorption in The Cosmic Web

    E-Print Network [OSTI]

    J. Richard Bond; James W. Wadsley

    1997-10-10

    We describe large scale structure at high redshift in terms of the Cosmic Web picture for {S,Lambda,O,H}CDM models: how galactic-scale ``peak-patches'', filaments and membranes create an interconnected intergalactic medium. The ideas are applied to our Ly$\\alpha$ forest simulations of ``shear-field patches''. We discuss simulation method and design, resolution dependence, the statistical combination of patches, UV flux scaling, and whether filtered Zel'dovich maps are useful. The response to changes in power spectrum shape and amplitude, and in cosmological parameters, is described. We also show Omega_b h^2 derived from UV rescaling is overestimated if the resolution is not adequate.

  15. Synthesis of alpha-amino acids

    DOE Patents [OSTI]

    Davis, J.W. Jr.

    1983-01-25

    A method is described for synthesizing alpha amino acids proceeding through novel intermediates of the formulas: R[sub 1]R[sub 2]C(OSOCl)CN, R[sub 1]R[sub 2]C(Cl)CN and [R[sub 1]R[sub 2]C(CN)O][sub 2]SO wherein R[sub 1] and R[sub 2] are each selected from hydrogen monovalent substituted and unsubstituted hydrocarbon radicals of 1 to 10 carbon atoms. The use of these intermediates allows the synthesis steps to be exothermic and results in an overall synthesis method which is faster than the synthesis methods of the prior art. No Drawings

  16. Surface Plasmon Enhanced Phosphorescent Organic Light Emitting Diodes

    SciTech Connect (OSTI)

    Guillermo Bazan; Alexander Mikhailovsky

    2008-08-01

    The objective of the proposed work was to develop the fundamental understanding and practical techniques for enhancement of Phosphorescent Organic Light Emitting Diodes (PhOLEDs) performance by utilizing radiative decay control technology. Briefly, the main technical goal is the acceleration of radiative recombination rate in organometallic triplet emitters by using the interaction with surface plasmon resonances in noble metal nanostructures. Increased photonic output will enable one to eliminate constraints imposed on PhOLED efficiency by triplet-triplet annihilation, triplet-polaron annihilation, and saturation of chromophores with long radiative decay times. Surface plasmon enhanced (SPE) PhOLEDs will operate more efficiently at high injection current densities and will be less prone to degradation mechanisms. Additionally, introduction of metal nanostructures into PhOLEDs may improve their performance due to the improvement of the charge transport through organic layers via multiple possible mechanisms ('electrical bridging' effects, doping-like phenomena, etc.). SPE PhOLED technology is particularly beneficial for solution-fabricated electrophosphorescent devices. Small transition moment of triplet emitters allows achieving a significant enhancement of the emission rate while keeping undesirable quenching processes introduced by the metal nanostructures at a reasonably low level. Plasmonic structures can be introduced easily into solution-fabricated PhOLEDs by blending and spin coating techniques and can be used for enhancement of performance in existing device architectures. This constitutes a significant benefit for a large scale fabrication of PhOLEDs, e.g. by roll-to-roll fabrication techniques. Besides multieexciton annihilation, the power efficacy of PhOLEDs is often limited by high operational bias voltages required for overcoming built-in potential barriers to injection and transport of electrical charges through a device. This problem is especially pronounced in solution processed OLEDs lacking the accuracy and precision of fabrication found in their small molecule counterparts. From this point of view, it seems beneficial to develop materials allowing reduction of the operation bias voltage via improvement of the charge injection. The materials sought have to be compatible with solution-based fabrication process and allow easy incorporation of metal nanostructures.

  17. Signatures of reionization on Lyman alpha emitters

    E-Print Network [OSTI]

    Pratika Dayal; Andrea Ferrara; Simona Gallerani

    2008-07-23

    We use a semi-analytic model of Lyman alpha emitters (LAEs) to constrain the reionization history. By considering two physically motivated scenarios in which reionization ends either early (ERM, z_i ~ 7) or late (LRM, z_i ~ 6), we fix the global value of the IGM neutral fraction (e.g. chi_{HI}=3 times 10^{-4}, 0.15 at z=6.56 for the ERM and LRM, respectively) leaving only the star formation efficiency and the effective escape fraction of Lya photons as free parameters. The ERM fits the observed LAE luminosity function (LF) at z=5.7 and 6.56 requiring no redshift evolution or mass dependence of the star formation efficiency, and LAE star formation rates (SFR) of 3-103 solar masses/year, contributing approximately 8% of the cosmic SFR density at z=5.7. The LRM requires a physically uncomfortable drop of approximately 4.5 times in the SFR of the emitters from z=6.5 to 5.7. Thus, the data seem to imply that the Universe was already highly ionized at z=6.56. The mass-dependent Lya transmissivity is between 0.36-0.51 (ERM) and less than 0.26 (LRM) at z=6.56. The LF data at z=4.5 imply an extra Lya line damping factor of approximately 0.25 possibly due to dust; the presence of a (clumpy) dust component with E(B-V) ~ 0.28 is also required to reproduce the observed large Lya equivalent widths at the same redshift. Additional useful information can be extracted from the line profile (weighted) skewness, found to be S_W=10-17 Angstrom for the two reionization models, which shows an interesting L_alpha-chi_{HI} anti-correlation, holding under the model assumptions. The shortcomings of the model and strategies to overcome them are discussed.

  18. Laser Isotope Enrichment for Medical and Industrial Applications

    SciTech Connect (OSTI)

    Leonard Bond

    2006-07-01

    Laser Isotope Enrichment for Medical and Industrial Applications by Jeff Eerkens (University of Missouri), Jay Kunze (Idaho State University), and Leonard Bond (Idaho National Laboratory) The principal isotope enrichment business in the world is the enrichment of uranium for commercial power reactor fuels. However, there are a number of other needs for separated isotopes. Some examples are: 1) Pure isotopic targets for irradiation to produce medical radioisotopes. 2) Pure isotopes for semiconductors. 3) Low neutron capture isotopes for various uses in nuclear reactors. 4) Isotopes for industrial tracer/identification applications. Examples of interest to medicine are targets to produce radio-isotopes such as S-33, Mo-98, Mo-100, W-186, Sn-112; while for MRI diagnostics, the non-radioactive Xe-129 isotope is wanted. For super-semiconductor applications some desired industrial isotopes are Si-28, Ga-69, Ge-74, Se-80, Te-128, etc. An example of a low cross section isotope for use in reactors is Zn-68 as a corrosion inhibitor material in nuclear reactor primary systems. Neutron activation of Ar isotopes is of interest in industrial tracer and diagnostic applications (e.g. oil-logging). . In the past few years there has been a sufficient supply of isotopes in common demand, because of huge Russian stockpiles produced with old electromagnetic and centrifuge separators previously used for uranium enrichment. Production of specialized isotopes in the USA has been largely accomplished using old ”calutrons” (electromagnetic separators) at Oak Ridge National Laboratory. These methods of separating isotopes are rather energy inefficient. Use of lasers for isotope separation has been considered for many decades. None of the proposed methods have attained sufficient proof of principal status to be economically attractive to pursue commercially. Some of the authors have succeeded in separating sulfur isotopes using a rather new and different method, known as condensation repression. In this scheme a gas, of the selected isotopes for enrichment, is irradiated with a laser at a particular wavelength that would excite only one of the isotopes. The entire gas is subject to low temperatures sufficient to cause condensation on a cold surface. Those molecules in the gas that the laser excited are not as likely to condense as are the unexcited molecules. Hence the gas drawn out of the system will be enriched in the isotope that was excited by the laser. We have evaluated the relative energy required in this process if applied on a commercial scale. We estimate the energy required for laser isotope enrichment is about 20% of that required in centrifuge separations, and 2% of that required by use of "calutrons".

  19. Method for using a yeast alpha-amylase promoter

    DOE Patents [OSTI]

    Gao, Johnway (Richland, WA); Skeen, Rodney S. (Pendleton, OR); Hooker, Brian S. (Kennewick, WA); Anderson, Daniel B. (Pasco, WA)

    2003-04-22

    The present invention provides the promoter clone discovery of an alpha-amylase gene of a starch utilizing yeast strain Schwanniomyces castellii. The isolated alpha-amylase promoter is an inducible promoter, which can regulate strong gene expression in starch culture medium.

  20. Generating long streams of $1/f^alpha$ noise

    E-Print Network [OSTI]

    S. Plaszczynski

    2008-07-09

    We review existing methods for generating long streams of 1/f^alpha noise ($0logistic maps, we give hints on how to design generators with $\\alpha>2$. The software is available from http://planck.lal.in2p3.fr/article.php3?id\\_article=8

  1. Radioactive isotopes in Danish drinking water

    E-Print Network [OSTI]

    Radioactive isotopes in Danish drinking water Sven P. Nielsen Risø National Laboratory Working OF INVESTIGATION 11 3 DESCRIPTION OF INVESTIGATION 12 4 RADIOACTIVITY IN DRINKING WATER 13 5 SAMPLING 15 6 27 #12;4 #12;5 Preface This project for investigation of radioactivity in drinking water shall

  2. Water isotopes and the general circulation

    E-Print Network [OSTI]

    Noone, David

    quantities are equator to pole temperature gradient, and the vertical thermal stratification #12;Isotopic" is the fractionation factor is a function of temperature F depends on large scale circulation and thermal state Both, temperature gradient/condensation) 2. Entrainment of non-depleted water (humidity, stratification/sheer) #12

  3. INTRODUCTION The oxygen isotopic compositions of minerals

    E-Print Network [OSTI]

    González, Luis A.

    .5 ka) and the associated migration of prairie into and out of the area (the prairie period; Dorale et of the Gulf of Mexico, Pacific, andArctic air masses (Bryson, 1966; Fig. 1). Gulf of Mexico air sup- plies of Mexico air masses and its precipitation is isotopically more negative than gulf moisture (e.g., typically

  4. Synthesis of rutherfordium isotopes in the {sup 238}U({sup 26}Mg, xn){sup 264-x}Rf reaction and study of their decay properties

    SciTech Connect (OSTI)

    Gates, J. M.; Garcia, M. A.; Dragojevic, I.; Folden, C. M. III; Nelson, S. L.; Nitsche, H.; Gregorich, K. E.; Stavsetra, L.; Sudowe, R.; Duellmann, Ch. E.; Dvorak, J.; Tuerler, A.; Eichler, R.; Loveland, W.; Pang, G. K.

    2008-03-15

    Isotopes of rutherfordium ({sup 258-261}Rf) were produced in irradiations of {sup 238}U targets with {sup 26}Mg beams. Excitation functions were measured for the 4n,5n, and 6n exit channels. Production of {sup 261}Rf in the 3n exit channel with a cross section of 28{sub -26}{sup +92} pb was observed. {alpha}-decay of {sup 258}Rf was observed for the first time with an {alpha}-particle energy of 9.05 {+-} 0.03 MeV and an {alpha}/total-decay branching ratio of 0.31 {+-} 0.11. In {sup 259}Rf, the electron capture/total-decay branching ratio was measured to be 0.15{+-}0.04. The measured half-lives for {sup 258}Rf, {sup 259}Rf, and {sup 260}Rf were 14.7{sub -1.0}{sup +1.2} ms, 2.5{sub -0.3}{sup +0.4} s, and 22.2{sub -2.4}{sup +3.0} ms, respectively, in agreement with literature data. The systematics of the {alpha}-decay Q-values and of the partial spontaneous fission half-lives were evaluated for even-even nuclides in the region of the N=152,Z=100 deformed shell. The influence of the N=152 shell on the {alpha}-decay Q-values for rutherfordium was observed to be similar to that of the lighter elements (96{<=}Z{<=}102). However, the N=152 shell does not stabilize the rutherfordium isotopes against spontaneous fission, as it does in the lighter elements (96{<=}Z{<=}102)

  5. Non-canonical mass laws in equilibrium isotopic fractionations: Evidence from the vapor pressure isotope effect of SF6

    E-Print Network [OSTI]

    Cartigny, Pierre

    Non-canonical mass laws in equilibrium isotopic fractionations: Evidence from the vapor pressure report experimental observations of the vapor pressure isotope effect, including 33 S/32 S and 34 S/32. That equilibrium involves a reversed vapor pressure isotope effect; i.e., vapor is between 2& and 3& higher in 34 S

  6. Colloidal semiconductor nanocrystals as nanoscale emissive probes in light emitting diodes and cell biology

    E-Print Network [OSTI]

    Huang, Hao, Ph. D. Massachusetts Institute of Technology

    2008-01-01

    This thesis employs colloidal semiconductor nanocrystals (NCs) as nanoscale emissive probes to investigate the physics of light emitting diodes (LEDs), as well as to unveil properties of cells that conventional imaging ...

  7. An evaluation of styrene levels emitted during cast polymer production of cultured marble building materials 

    E-Print Network [OSTI]

    Bell, Lewis Ray

    1994-01-01

    emitted into the surrounding facility and outside ambient air. These concentrations were tabulated and compared against styrene levels from each major process in the fabrication of cultured marble. Additionally, the removal effectiveness of the ventilation...

  8. A strategy for the use of light emitting diodes by autonomous underwater vehicles

    E-Print Network [OSTI]

    Curran, Joseph R. (Joseph Robinson)

    2004-01-01

    Light Emitting Diode (LED) technology has advanced dramatically in a few short years. An expensive and difficult to manufacture LED array containing nearly 100 individual LEDs and measuring at least 5 cm² can now be replaced ...

  9. Collisionless ion collection by non-emitting spherical bodies in E x B fields

    E-Print Network [OSTI]

    Patacchini, Leonardo

    2010-01-01

    The three-dimensional interaction of a magnetized, collisionless flowing plasma with a non-emitting conducting sphere is solved in the entire range of physically allowed parameters, in the ion-collecting regime. This can ...

  10. Efficiency loss mechanisms in colloidal quantum-dot light-emitting diodes

    E-Print Network [OSTI]

    Shirasaki, Yasuhiro

    2013-01-01

    Saturated and tunable emission colors make colloidal quantum-dot light-emitting diodes (QD-LEDs) interesting for the next generation of display and lighting technologies. However, there still remain various hurdles to the ...

  11. Method and apparatus for improving the performance of light emitting diodes

    DOE Patents [OSTI]

    Lowery, Christopher H. (Fremont, CA); McElfresh, David K. (Union City, CA); Burchet, Steve (Cedar Crest, NM); Adolf, Douglas B. (Albuquerque, NM); Martin, James (Tijeras, NM)

    1996-01-01

    A method for increasing the resistance of a light emitting diode and other semiconductor devices to extremes of temperature is disclosed. During the manufacture of the light emitting diode, a liquid coating is applied to the light emitting die after the die has been placed in its lead frame. After the liquid coating has been placed on the die and its lead frames, a thermosetting encapsulant material is placed over the coating. The operation that cures the thermosetting material leaves the coating liquid intact. As the die and the encapsulant expand and contract at different rates with respect to changes in temperature, and as in known light emitting diodes the encapsulating material adheres to the die and lead frames, this liquid coating reduces the stresses that these different rates of expansion and contraction normally cause by eliminating the adherence of the encapsulating material to the die and frame.

  12. Diffusion injected multi-quantum well light-emitting diode structure

    SciTech Connect (OSTI)

    Riuttanen, L., E-mail: lauri.riuttanen@aalto.fi; Nykänen, H.; Svensk, O.; Suihkonen, S.; Sopanen, M. [Department of Micro- and Nanosciences, Aalto University, P.O. Box 13500, FI-00076 Aalto (Finland); Kivisaari, P.; Oksanen, J.; Tulkki, J. [Department of Biomedical Engineering and Computational Science, Aalto University, P.O. Box 12200, FI-00076 Aalto (Finland)

    2014-02-24

    The attention towards light-emitting diode (LED) structures based on nanowires, surface plasmon coupled LEDs, and large-area high-power LEDs has been increasing for their potential in increasing the optical output power and efficiency of LEDs. In this work we demonstrate an alternative way to inject charge carriers into the active region of an LED, which is based on completely different current transport mechanism compared to conventional current injection approaches. The demonstrated structure is expected to help overcoming some of the challenges related to current injection with conventional structures. A functioning III-nitride diffusion injected light-emitting diode structure, in which the light-emitting active region is located outside the pn-junction, is realized and characterized. In this device design, the charge carriers are injected into the active region by bipolar diffusion, which could also be utilized to excite otherwise challenging to realize light-emitting structures.

  13. Artist's rendition of a 1.54 mm-emitting laser

    E-Print Network [OSTI]

    Sargent, Edward H. "Ted"

    Artist's rendition of a 1.54 mm-emitting laser made by solution- processing a colloidal quantum dot detectivity, represented by the symbol D*. Epitaxially grown InGaAs devices on an InP substrate achieve

  14. Development of monolithic CMOS-compatible visible light emitting diode arrays on silicon

    E-Print Network [OSTI]

    Chilukuri, Kamesh

    2006-01-01

    The synergies associated with integrating Si-based CMOS ICs and III-V-material-based light-emitting devices are very exciting and such integration has been an active area of research and development for quite some time ...

  15. Fiber Fabry-Perot interferometer (FFPI) sensor using vertical cavity surface emitting laser (VCSEL) 

    E-Print Network [OSTI]

    Lee, Kyung-Woo

    2006-10-30

    This research represents the first effort to apply vertical cavity surface emitting lasers (VCSELs) to the monitoring of interferometric fiber optic sensors. Modulation of the drive current causes thermal tuning of the laser light frequency...

  16. Fabrication and optimization of light emitting devices with core-shell quantum dots

    E-Print Network [OSTI]

    Song, Katherine Wei

    2013-01-01

    Quantum dot light emitting devices (QD-LEDs) are promising options for the next generation of solid state lighting, color displays, and other optoelectronic applications. Overcoating quantum dots (QDs) -- semiconducting ...

  17. Energy Policy Seminar Series: Climate impacts of methane-emitting energy technologies

    E-Print Network [OSTI]

    Chen, Kuang-Yu

    of greenhouse gases, most notably methane and carbon dioxide, and these gases have dissimilar properties. This research finds that methane-emitting energy such as natural gas becomes significantly more carbon dioxide

  18. Demonstration Assessment of Light-Emitting Diode (LED) Post-Top...

    Office of Scientific and Technical Information (OSTI)

    Central Park in New York City A review of five post-top light-emitting diode (LED) pedestrian luminaires installed in New York City's Central Park for possible replacement to the...

  19. Adhesion in flexible organic and hybrid organic/inorganic light emitting device and solar cells

    SciTech Connect (OSTI)

    Yu, D.; Kwabi, D.; Akogwu, O.; Du, J. [Princeton Institute of Science and Technology of Materials, Princeton University, 70 Prospect Street, Princeton, New Jersey 08544 (United States); Department of Mechanical and Aerospace Engineering, Princeton University, Olden Street, Princeton, New Jersey 08544 (United States); Oyewole, O. K. [Department of Theoretical and Applied Physics, African University of Science and Technology, Km 10, Airport Road, Galadimawa, Abuja, Federal Capital Territory (Nigeria); Department of Materials Science and Engineering, Kwara State University, Malete, Kwara State (Nigeria); Tong, T. [Princeton Institute of Science and Technology of Materials, Princeton University, 70 Prospect Street, Princeton, New Jersey 08544 (United States); Department of Electrical Engineering, Princeton University, Olden Street, Princeton, New Jersey 08544 (United States); Anye, V. C.; Rwenyagila, E. [Department of Materials Science and Engineering, African University of Science and Technology, Km 10, Airport Road, Galadimawa, Abuja, Federal Capital Territory (Nigeria); Asare, J.; Fashina, A. [Department of Theoretical and Applied Physics, African University of Science and Technology, Km 10, Airport Road, Galadimawa, Abuja, Federal Capital Territory (Nigeria); Soboyejo, W. O. [Princeton Institute of Science and Technology of Materials, Princeton University, 70 Prospect Street, Princeton, New Jersey 08544 (United States); Department of Mechanical and Aerospace Engineering, Princeton University, Olden Street, Princeton, New Jersey 08544 (United States); Department of Materials Science and Engineering, African University of Science and Technology, Km 10, Airport Road, Galadimawa, Abuja, Federal Capital Territory (Nigeria)

    2014-08-21

    This paper presents the results of an experimental study of the adhesion between bi-material pairs that are relevant to organic light emitting devices, hybrid organic/inorganic light emitting devices, organic bulk heterojunction solar cells, and hybrid organic/inorganic solar cells on flexible substrates. Adhesion between the possible bi-material pairs is measured using force microscopy (AFM) techniques. These include: interfaces that are relevant to organic light emitting devices, hybrid organic/inorganic light emitting devices, bulk heterojunction solar cells, and hybrid combinations of titanium dioxide (TiO{sub 2}) and poly(3-hexylthiophene). The results of AFM measurements are incorporated into the Derjaguin-Muller-Toporov model for the determination of adhesion energies. The implications of the results are then discussed for the design of robust organic and hybrid organic/inorganic electronic devices.

  20. Physical properties and design of light-emitting devices based on organic materials and nanoparticles

    E-Print Network [OSTI]

    Anikeeva, Polina Olegovna

    2009-01-01

    This thesis presents the detailed experimental and theoretical characterization of light-emitting devices (LEDs) based on organic semiconductors and colloidal quantum dots (QDs). This hybrid material system has several ...

  1. Climate effects of seasonally varying Biomass Burning emitted Carbonaceous Aerosols (BBCA)

    E-Print Network [OSTI]

    Jeong, Gill-Ran

    The climate impact of the seasonality of Biomass Burning emitted Carbonaceous Aerosols (BBCA) is studied using an aerosol-climate model coupled with a slab ocean model in a set of 60-year long simulations, driven by BBCA ...

  2. Note: Scanned multi-light-emitting-diode illumination for volumetric particle image velocimetry

    E-Print Network [OSTI]

    Wettlaufer, John S.

    Note: Scanned multi-light-emitting-diode illumination for volumetric particle image velocimetry M-based three-dimensional illumination systems for volumetric particle image velocimetry PIV that uses a single

  3. Elastic alpha scattering experiments and the alpha-nucleus optical potential at low energies

    E-Print Network [OSTI]

    P. Mohr; G. G. Kiss; Zs. Fülöp; D. Galaviz; Gy. Gyürky; E. Somorjai

    2012-12-12

    High precision angular distribution data of ($\\alpha$,$\\alpha$) elastic scattering are presented for the nuclei $^{89}$Y, $^{92}$Mo, $^{106,110,116}$Cd, $^{112,124}$Sn, and $^{144}$Sm at energies around the Coulomb barrier. Such data with small experimental uncertainties over the full angular range (20-170 degrees) are the indispensable prerequisite for the extraction of local optical potentials and for the determination of the total reaction cross section $\\sigma_{\\rm{reac}}$. A systematic fitting procedure was applied to the presented experimental scattering data to obtain comprehensive local potential parameter sets which are composed of a real folding potential and an imaginary potential of Woods-Saxon surface type. The obtained potential parameters were used in turn to construct a new systematic $\\alpha$-nucleus potential with very few parameters. Although this new potential cannot reproduce the angular distributions with the same small deviations as the local potential, the new potential is able to predict the total reaction cross sections for all cases under study.

  4. A simple procedure to prepare spherical {alpha}-alumina powders

    SciTech Connect (OSTI)

    Liu Hongyu [State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China); Ning Guiling [State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China)], E-mail: ninggl@dlut.edu.cn; Gan Zhihong; Lin Yuan [State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China)

    2009-04-02

    Spherical {alpha}-alumina powders were prepared by the controlled hydrolysis of aluminum isopropoxide in a hydrolysis system consisting of octanol and acetonitrile. Diverse solvents to dissolve reactant formed diverse hydrolysis systems and affected particle shape of {alpha}-alumina powders. The precursors crystallized to {gamma}-alumina at 1000 deg. C and converted to {alpha}-alumina at 1150 deg. C without intermediate phases. The particle morphology of precursor was retained after it crystallized to {alpha}-alumina. The heating rate influenced the particle shape and the state of agglomeration during calcination process. The thermal properties of the precursors were characterized by thermal gravimetric and differential thermal analysis. X-ray diffraction technique was used to confirm the conversion of crystalline phase of alumina powders from amorphous to {alpha}-phase. Transmission electron microscopy was used to investigate the morphologies and size of the precursors and products.

  5. Integration of photoactive and electroactive components with vertical cavity surface emitting lasers

    DOE Patents [OSTI]

    Bryan, R.P.; Esherick, P.; Jewell, J.L.; Lear, K.L.; Olbright, G.R.

    1997-04-29

    A monolithically integrated optoelectronic device is provided which integrates a vertical cavity surface emitting laser and either a photosensitive or an electrosensitive device either as input or output to the vertical cavity surface emitting laser either in parallel or series connection. Both vertical and side-by-side arrangements are disclosed, and optical and electronic feedback means are provided. Arrays of these devices can be configured to enable optical computing and neural network applications. 9 figs.

  6. Strontium-isotope stratigraphy of Enewetak Atoll

    SciTech Connect (OSTI)

    Ludwig, K.R.; Halley, R.B.; Simmons, K.R.; Peterman, Z.E.

    1988-02-01

    /sup 87/Sr//sup 86/Sr ratios determined for samples from a 350 m core of Neogene lagoonal, shallow-water limestones from Enewetak Atoll display a remarkably informative trend. Like the recently published data for Deep Sea Drilling Project (DSDP) carbonates, /sup 87/Sr//sup 86/Sr at Enewetak increases monotonically but not smoothly from the early Miocene to the Pleistocene. The data show intervals of little or no change in /sup 87/Sr//sup 86/Sr, punctuated by sharp transitions to lower values toward greater core depths. The sharp transitions correlate with observed solution disconformities caused by periods of subaerial erosion, whereas the intervals of little or no change in /sup 87/Sr//sup 86/Sr correspond to intervals of rapid accumulation of shallow-water carbonate sediments. When converted to numerical ages using the published DSDP 590B trend, the best-resolved time breaks are at 282 m (12.3 to 18.2 Ma missing) and 121.6 m (3.0 to 5.3 Ma missing) below the lagoon floor. At Enewetak, Sr isotopes offer a stratigraphic resolution for these shallow-marine Neogene carbonates comparable to that of nannofossil zonation in deep-sea carbonates (0.3-3 m.y.). In addition, the correlation of times of Sr-isotope breaks at Enewetak with times of rapid Sr-isotope change in the DSDP 590B samples confirms the importance of sea-level changes in the evolution of global-marine Sr isotopes and shows that the Sr-isotope response to sea-level falls is rapid.

  7. Enriching stable isotopes: Alternative use for Urenco technology

    SciTech Connect (OSTI)

    Rakhorst, H.; de Jong, P.G.T.; Dawson, P.D.

    1996-12-31

    The International Urenco Group utilizes a technologically advanced centrifuge process to enrich uranium in the fissionable isotope {sup 235}U. The group operates plants in the United Kingdom, the Netherlands, and Germany and currently holds a 10% share of the multibillion dollar world enrichment market. In the early 1990s, Urenco embarked on a strategy of building on the company`s uniquely advanced centrifuge process and laser isotope separation (LIS) experience to enrich nonradioactive isotopes colloquially known as stable isotopes. This paper summarizes the present status of Urenco`s stable isotopes business.

  8. THE MULTI-ISOTOPE PROCESS (MIP) MONITOR: A NEAR-REAL-TIME, NON-DESTRUCTIVE, INDICATOR OF SPENT NUCLEAR FUEL REPROCESSING CONDITIONS

    SciTech Connect (OSTI)

    Schwantes, Jon M.; Orton, Christopher R.; Fraga, Carlos G.; Douglas, Matthew; Christensen, Richard

    2010-05-07

    Researchers from Pacific Northwest National Laboratory and The Ohio State University are working to develop a system for monitoring spent nuclear fuel reprocessing facilities on-line, non-destructively, and in near-real-time. This method, known as the Multi-Isotope Process (MIP) Monitor, is based upon the measurement of distribution patterns of a suite of indicator (radioactive) isotopes present within product and waste streams of a nuclear reprocessing facility. Signatures from these indicator isotopes are monitored on-line by gamma spectrometry and compared, in near-real-time, to patterns representing "normal" process conditions using multivariate pattern recognition software. By targeting gamma-emitting indicator isotopes, the MIP Monitor approach is compatible with the use of small, portable, high-resolution gamma detectors that may be easily deployed throughout an existing facility. In addition, utilization of a suite of radio-elements, including ones with multiple oxidation states, increases the likelihood that attempts to divert material via process manipulation would be detected. Proof-of-principle modeling exercises simulating changes in acid strength have been completed and the results are promising. Laboratory validation is currently under way and significant results are available. The latest experimental results, along with an overview of the method will be presented.

  9. MONITORING SPENT NUCLEAR FUEL REPROCESSING CONDITIONS NON-DESTRUCTIVELY AND IN NEAR-REAL-TIME USING THE MULTI-ISOTOPE PROCESS (MIP) MONITOR

    SciTech Connect (OSTI)

    Orton, Christopher R.; Fraga, Carlos G.; Douglas, Matthew; Christensen, Richard; Schwantes, Jon M.

    2010-05-07

    Researchers from Pacific Northwest National Laboratory and The Ohio State University are working to develop a system for monitoring spent nuclear fuel reprocessing facilities on-line, nondestructively, and in near-real-time. This method, known as the Multi-Isotope Process (MIP) Monitor, is based upon the measurement of distribution patterns of a suite of indicator (radioactive) isotopes present within product and waste streams of a nuclear reprocessing facility. Signatures from these indicator isotopes are monitored on-line by gamma spectrometry and compared, in near-real-time, to patterns representing "normal" process conditions using multivariate pattern recognition software. By targeting gamma-emitting indicator isotopes, the MIP Monitor approach is compatible with the use of small, portable, high-resolution gamma detectors that may be easily deployed throughout an existing facility. In addition, utilization of a suite of radio-elements, including ones with multiple oxidation states, increases the likelihood that attempts to divert material via process manipulation would be detected. Proof-of-principle modeling exercises simulating changes in acid strength have been completed and the results are promising. Laboratory testing is currently under way and significant results are available. Recent experimental results, along with an overview of the method are presented.

  10. Quasiparticle-vibration coupling in relativistic framework: shell structure of Z=120 isotopes

    E-Print Network [OSTI]

    Elena Litvinova

    2011-08-17

    For the first time, the shell structure of open-shell nuclei is described in a fully self-consistent extension of the covariant energy density functional theory. The approach implies quasiparticle-vibration coupling for superfluid systems. One-body Dyson equation formulated in the doubled quasiparticle space of Dirac spinors is solved for nucleonic propagators in tin isotopes which represent the reference case: the obtained energies of the single-quasiparticle levels and their spectroscopic amplitudes are in agreement with data. The model is applied to describe the shell evolution in a chain of superheavy isotopes $^{292,296,300,304}$120 and finds a rather stable proton spherical shell closure at Z = 120. An interplay of the pairing correlations and the quasiparticle-phonon coupling gives rise for a smooth evolution of the neutron shell gap between N = 172 and N = 184 neutron numbers. Vibrational corrections to the alpha decay energies reach several hundred keV and can be either positive and negative, thus also smearing the shell effects.

  11. A New Kind of Column Materials for Gas Chromatographic Hydrogen Isotope Separation

    SciTech Connect (OSTI)

    Hara, M.; Shima, H.; Akamaru, S.; Abe, T.; Matsuyama, M.; Watanabe, K. [Toyama University (Japan)

    2005-07-15

    A new kind of materials that can be applied to a gas chromatographic hydrogen isotope separation system was developed to reduce the amount of Pd-Pt alloy required for making the column and to improve the separation efficiency. Pd and Pt were deposited on {alpha}-Al{sub 2}O{sub 3} powder by using a barrel sputtering system. Prepared sample powder was characterized from surface morphology, element distributions on the surface, composition and crystallinity. The characterization showed that a uniform layer of Pd-Pt alloy with expected composition was formed on Al{sub 2}O{sub 3} particles. The crystallinity, however, was poor, but improved after annealing at 1073 K for 2 hours. The hydrogen absorbing behavior was also improved by the annealing. A separation column was prepared from the annealed powder and was subjected to experiments on hydrogen isotope separation. The column of annealed powder gave considerably good separation efficiency around room temperature, in spite that only 0.35 g of Pd-Pt was used for the column. The amount of Pd-Pt alloy used here should be compared to previous results, where 1.5 g of Pd-Pt powder was required for high separation efficiency. The new material was quite effective to reduce the amount of Pd-Pt alloy without compromising the separation efficiency and can give further improvement.

  12. Microscopic description of fission in neutron-rich Radium isotopes with the Gogny energy density functional

    E-Print Network [OSTI]

    Rodriguez-Guzman, R R

    2015-01-01

    Mean field calculations, based on the D1S, D1N and D1M parametrizations of the Gogny energy density functional, have been carried out to obtain the potential energy surfaces relevant to fission in several Ra isotopes with the neutron number 144 $\\le$ N $\\le$ 176. Inner and outer barrier heights as well as first and second isomer excitation energies are given. The existence of a well developed third minimum along the fission paths of Ra nuclei, is analyzed in terms of the energetics of the "fragments" defining such elongated configuration. The masses and charges of the fission fragments are studied as functions of the neutron number in the parent Ra isotope. The comparison between fission and $\\alpha$-decay half-lives, reveals that the former becomes faster for increasing neutron numbers. Though there exists a strong variance of the results with respect to the parameters used in the computation of the spontaneous fission rate, a change in tendency is observed at N=164 with a steady increase that makes heavier ...

  13. Rapid fusion method for the determination of refractory thorium and uranium isotopes in soil samples

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

    Maxwell, Sherrod L.; Hutchison, Jay B.; McAlister, Daniel R.

    2015-02-14

    Recently, approximately 80% of participating laboratories failed to accurately determine uranium isotopes in soil samples in the U.S Department of Energy Mixed Analyte Performance Evaluation Program (MAPEP) Session 30, due to incomplete dissolution of refractory particles in the samples. Failing laboratories employed acid dissolution methods, including hydrofluoric acid, to recover uranium from the soil matrix. The failures illustrate the importance of rugged soil dissolution methods for the accurate measurement of analytes in the sample matrix. A new rapid fusion method has been developed by the Savannah River National Laboratory (SRNL) to prepare 1-2 g soil sample aliquots very quickly, withmore »total dissolution of refractory particles. Soil samples are fused with sodium hydroxide at 600 ºC in zirconium crucibles to enable complete dissolution of the sample. Uranium and thorium are separated on stacked TEVA and TRU extraction chromatographic resin cartridges, prior to isotopic measurements by alpha spectrometry on cerium fluoride microprecipitation sources. Plutonium can also be separated and measured using this method. Batches of 12 samples can be prepared for measurement in « less

  14. Demonstration of a semipolar (10(1)over-bar(3)over-bar) InGaN/GaN green light emitting diode

    E-Print Network [OSTI]

    2005-01-01

    InGaN / GaN green light emitting diode R. Sharma, a? P. M.green ??525 nm? light emitting diode ?LED?. The fabricated

  15. Method of preparing mercury with an arbitrary isotopic distribution

    DOE Patents [OSTI]

    Grossman, M.W.; George, W.A.

    1986-12-16

    This invention provides for a process for preparing mercury with a predetermined, arbitrary, isotopic distribution. In one embodiment, different isotopic types of Hg[sub 2]Cl[sub 2], corresponding to the predetermined isotopic distribution of Hg desired, are placed in an electrolyte solution of HCl and H[sub 2]O. The resulting mercurous ions are then electrolytically plated onto a cathode wire producing mercury containing the predetermined isotopic distribution. In a similar fashion, Hg with a predetermined isotopic distribution is obtained from different isotopic types of HgO. In this embodiment, the HgO is dissolved in an electrolytic solution of glacial acetic acid and H[sub 2]O. The isotopic specific Hg is then electrolytically plated onto a cathode and then recovered. 1 fig.

  16. Thalamocortical Mechanisms for the Anteriorization of Alpha Rhythms during Propofol-Induced Unconsciousness

    E-Print Network [OSTI]

    Vijayan, Sujith

    As humans are induced into a state of general anesthesia via propofol, the normal alpha rhythm (8–13 Hz) in the occipital cortex disappears and a frontal alpha rhythm emerges. This spatial shift in alpha activity is called ...

  17. EASY-II: a system for modelling of n, d, p, {\\gamma} and {\\alpha} activation and transmutation processes

    E-Print Network [OSTI]

    Sublet, Jean-Christophe; Morgan, Guy; Koning, Arjan; Rochman, Dimitri

    2013-01-01

    EASY-II is designed as a functional replacement for the previous European Activation System, EASY-2010. It has extended nuclear data and new software, FISPACT-II, written in object-style Fortran to provide new capabilities for predictions of activation, transmutation, depletion and burnup. The new FISPACT-II code has allowed us to implement many more features in terms of energy range, up to GeV; incident particles: alpha, gamma, proton, deuteron and neutron; and neutron physics: self-shielding effects, temperature dependence, pathways analysis, sensitivity and error estimation using covariance data. These capabilities cover most application needs: nuclear fission and fusion, accelerator physics, isotope production, waste management and many more. In parallel, the maturity of modern general-purpose libraries such as TENDL-2012 encompassing thousands of target nuclides, the evolution of the ENDF format and the capabilities of the latest generation of processing codes PREPRO-2012, NJOY2012 and CALENDF-2010 have ...

  18. Antihydrogen Trapped in the ALPHA Experiment

    ScienceCinema (OSTI)

    None

    2011-04-25

    In 2010 the ALPHA collaboration succeeded in trapping antihydrogen atoms for the first time.[i]  Stored antihydrogen promises to be a unique tool for making high precision measurements of the structure of this first anti-atom. Achieving this milestone presented several substantial experimental challenges and this talk will describe how they were overcome.   The unique design features of the ALPHA apparatus will be explained.[ii]  These allow a high intensity positron source and an antiproton imaging detector similar to the one used in the ATHENA[iii] experiment to be combined with an innovative magnet design of the anti-atom trap. This seeks to minimise the perturbations to trapped charged particles which may cause particle loss and heating[iv].   The diagnostic techniques used to measure the diameter, number, density, and temperatures of both plasmas will be presented as will the methods developed to actively compress and cool of both plasma species to sizes and temperatures [v],[vi], [vii] where trapping attempts with a reasonable chance of success can be tried.   The results of the successful trapping experiments will be outlined as well as some subsequent experiments to improve the trapping rate and storage time. [i] 'Trapped antihydrogen' G.B. Andresen et al., Nature 468, 673 (2010) [ii]'A Magnetic Trap for Antihydrogen Confinement' W. Bertsche et al., Nucl. Instr. Meth. Phys. Res. A566, 746 (2006) [iii] Production and detection of cold antihydrogen atoms M.Amoretti et al., Nature 419, 456 (2002). [iv]' Antihydrogen formation dynamics in a multipolar neutral anti-atom trap' G.B. Andresen et al., Phys. Lett. B 685, 141 (2010) [v]' Evaporative Cooling of Antiprotons to Cryogenic Temperatures',                                   G.B. Andresen et al. Phys. Rev. Lett 105, 013003 (2010) [vi]'Compression of Antiproton Clouds for Antihydrogen Trapping' G. B. Andresen et al. Phys. Rev. Lett 100, 203401 (2008) [vii]  'Autoresonant Excitation of Antiproton Plasmas' G.B. Andresen et al., Phys. Rev. Lett. 106, 025002 (2011) Organizer: Ferdinand Hahn PH/DT Detector Seminar webpage  

  19. Thick-Target Neutron Yield from the 19F(alpha,n) Reaction

    E-Print Network [OSTI]

    E. B. Norman; T. E. Chupp; K. T. Lesko; G. L. Woodruff; P. J. Grant

    2015-01-10

    Thick-target neutron yields from the 19F(alpha,n) reaction are reported for E(alpha) = 3.5 - 10.0 MeV.

  20. Particle Physics Aspects of Antihydrogen Studies with ALPHA at CERN

    E-Print Network [OSTI]

    ALPHA Collaboration; M. C. Fujiwara; G. B. Andresen; W. Bertsche; P. D. Bowe; C. C. Bray; E. Butler; C. L. Cesar; S. Chapman; M. Charlton; J. Fajans; R. Funakoshi; D. R. Gill; J. S. Hangst; W. N. Hardy; R. S. Hayano; M. E. Hayden; A. J. Humphries; R. Hydomako; M. J. Jenkins; L. V. Jorgensen; L. Kurchaninov; W. Lai; R. Lambo; N. Madsen; P. Nolan; K. Olchanski; A. Olin; A. Povilus; P. Pusa; F. Robicheaux; E. Sarid; S. Seif El Nasr; D. M. Silveira; J. W. Storey; R. I. Thompson; D. P. van der Werf; L. Wasilenko; J. S. Wurtele; Y. Yamazaki

    2008-05-27

    We discuss aspects of antihydrogen studies, that relate to particle physics ideas and techniques, within the context of the ALPHA experiment at CERN's Antiproton Decelerator facility. We review the fundamental physics motivations for antihydrogen studies, and their potential physics reach. We argue that initial spectroscopy measurements, once antihydrogen is trapped, could provide competitive tests of CPT, possibly probing physics at the Planck Scale. We discuss some of the particle detection techniques used in ALPHA. Preliminary results from commissioning studies of a partial system of the ALPHA Si vertex detector are presented, the results of which highlight the power of annihilation vertex detection capability in antihydrogen studies.