Sample records for alpha emitting isotopes

  1. alpha-particle-emitting isotope 259db: Topics by E-print Network

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

    CERN Preprints Summary: Currently, 31 actinium, 31 thorium, 28 protactinium, and 23 uranium isotopes have so far been observed; the discovery of these isotopes is discussed. For...

  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. alpha particle-emitting isotopes: Topics by E-print Network

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

    -occur- ring radioactive isotopes such as uranium, and radium also have Maximum Contaminant Levels (MCL and 25 picoCuries per liter (pCiL). Although activities were below the...

  4. alpha emitting radionuclides: Topics by E-print Network

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

    on the response function of a TeO2 bolometer to alpha's emitted by 147Sm dissolved in the crystal at the growth phase. A Quenching Factor of (1.0076pm...

  5. Determination of isotopic thorium in biological samples by combined alpha spectrometry and neutron activation analysis.

    SciTech Connect (OSTI)

    Glover, S. E. (Samuel E.)

    2003-01-01T23:59:59.000Z

    Thorium is a naturally occurring element for whom all isotopes are radioactive . Many of these isotopes are alpha emitting radionuclides, some of which have limits for inhalation lower than plutonium in current regulations . Neutron activation analysis can provide for the low-level determination of 232Th but can not determine other isotopes of dosimetric importance . Biological and environmental samples often have large quantities of materials which activate strongly, limiting the capabilities of instrumental neutron activiation analysis . This paper will discuss the application of a combined technique using alpha spectrometry and radiochemical neutron activiation analysis for the determination of isotopic thorium .

  6. alpha particle emitting: Topics by E-print Network

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

    2002-07-31 462 Angular momentum transport and proton-alpha differential streaming in the solar wind CERN Preprints Summary: The effect of solar rotation on the proton-alpha...

  7. alpha particles emitted: Topics by E-print Network

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

    2002-07-31 462 Angular momentum transport and proton-alpha differential streaming in the solar wind CERN Preprints Summary: The effect of solar rotation on the proton-alpha...

  8. 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)

    2010-06-15T23:59:59.000Z

    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.

  9. alpha-particle emitting radiopharmaceuticals: Topics by E-print...

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

    44 Incidence characteristics of alpha particles on detectors irradiated in a radon progeny atmosphere Biology and Medicine Websites Summary: Incidence characteristics of...

  10. Artificial Alpha-Active Bismuth Isotopes

    E-Print Network [OSTI]

    Templeton, D.H.

    2010-01-01T23:59:59.000Z

    Laboratory Contract No. W-7405-eng-48 ARTIFICIAL ALPHA-thD." 203. Contract No. W-7405-eng-48 To be published as awith the Atom~c N~mber W~7405- eng-48 Enerp:y Commission in

  11. 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

    2012-12-12T23:59:59.000Z

    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.

  12. FAST-RESPONSE ISOTOPIC ALPHA CONTINUOUS AIR MONITOR (CAM)

    SciTech Connect (OSTI)

    Keith D. Patch

    2000-04-28T23:59:59.000Z

    The objective of this effort is to develop and test a novel Continuous Air Monitor (CAM) instrument for monitoring alpha-emitting radionuclides, using a technology that can be applied to Continuous Emission Monitoring (CEM) of thermal treatment system off gas streams. The CAM instrument will have very high alpha spectral resolution and provide real-time, on-line monitoring suitable for alerting workers of high concentrations of alpha-emitting radionuclides in the ambient air and for improved control of decontamination, dismantlement, and air emission control equipment. Base Phase I involves the design, development, and preliminary testing of a laboratory-scale instrument. Testing will initially be conducted using naturally-occurring radon progeny in ambient air. In the Optional Phase II, the Base Phase I instrument will be critically evaluated at the Lovelace Respiratory Research Institute (LRRI) with characterized plutonium aerosols; then an improved instrument will be built and field-tested at a suitable DOE site.

  13. On the Diffuse Lyman-alpha Halo Around Lyman-alpha Emitting Galaxies

    E-Print Network [OSTI]

    Lake, Ethan; Cen, Renyue; Sadoun, Raphael; Momose, Rieko; Ouchi, Masami

    2015-01-01T23:59:59.000Z

    Ly$\\alpha$ photons scattered by neutral hydrogen atoms in the circumgalactic media or produced in the halos of star-forming galaxies are expected to lead to extended Ly$\\alpha$ emission around galaxies. Such low surface brightness Ly$\\alpha$ halos (LAHs) have been detected by stacking Ly$\\alpha$ images of high-redshift star-forming galaxies. We study the origin of LAHs by performing radiative transfer modeling of nine $z=3.1$ Lyman-Alpha Emitters (LAEs) in a high resolution hydrodynamic galaxy formation simulation. We develop a method of computing the mean Ly$\\alpha$ surface brightness profile of each LAE by effectively integrating over many different observing directions. Without adjusting any parameters, our model yields an average Ly$\\alpha$ surface brightness profile in remarkable agreement with observations. We find that observed LAHs can not be accounted for solely by photons originating from the central LAE and scattered to large radii by hydrogen atoms in the circumgalactic gas. Instead, Ly$\\alpha$ em...

  14. alpha-particle emitting 211at: Topics by E-print Network

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

    Ag as anode Institute of Physics. DOI: 10.10631.2172734 Active-matrix organic light-emitting diode AMOLED displays have 108 Interference of spontaneously emitted photons Quantum...

  15. Dynamics of the Lyman alpha and C IV emitting gas in 3C 273

    E-Print Network [OSTI]

    Stephane Paltani; Marc Turler

    2002-10-04T23:59:59.000Z

    In this paper we study the variability properties of the Lyman alpha and C IV emission lines in 3C273 using archival IUE observations. Our data show for the first time the existence of variability on time scales of several years. We study the spatial distribution and the velocity field of the emitting gas by performing detailed analyses on the line variability using correlations, 1D and 2D response functions, and principal component analysis. In both lines we find evidence for two components, one which has the dynamic properties of gas in Keplerian motion around a black hole with a mass of the order of 10^9 Mo, and one which is characterized by high, blue-shifted velocities at large lag. There is no indication of the presence of optically thick emission medium neither in the Lya, nor in the Civ response functions. The component characterized by blue-shifted velocities, which is comparatively much stronger in Civ than in Lya, is more or less compatible with being the result of gas falling towards the central black hole with free-fall acceleration. We propose however that the line emission at high, blue-shifted velocities is better explained in terms of entrainment of gas clouds by the jet. This gas is therefore probably collisionally excited as a result of heating due to the intense infrared radiation from the jet, which would explain the strength of this component in Civ relative to Lya. This phenomenon might be a signature of disk-jet interaction.

  16. Characterization of Tank 48H Samples for Alpha Activity and Actinide Isotopics

    SciTech Connect (OSTI)

    Hobbs, D.T. [Westinghouse Savannah River Company, AIKEN, SC (United States); Coleman, C.J.; Hay, M.S.

    1995-12-04T23:59:59.000Z

    This document reports the total alpha activity and actinide isotopic results for samples taken from Tank 48H prior to the addition of sodium tetraphenylborate and MST in Batch {number_sign}1 of the ITP process. This information used to determine the quantity of MST for Batch {number_sign}1 of the ITP process and the total actinide content in the tank for dose calculations.

  17. A connection between extremely strong Damped Lyman-alpha Systems and Lyman-alpha Emitting Galaxies at small impact parameters

    E-Print Network [OSTI]

    Noterdaeme, P; Paris, I; Cai, Z; Finley, H; Ge, J; Pieri, M M; York, D G

    2014-01-01T23:59:59.000Z

    We present a study of ~100 high redshift (z~2-4) extremely strong damped Lyman-alpha systems (ESDLA, with N(HI)>0.5x10^22 cm^-2) detected in quasar spectra from the Baryon Oscillation Spectroscopic Survey SDSS-III DR11. We study the neutral hydrogen, metal, and dust content of this elusive population of absorbers and confirm our previous finding that the high column density end of the N(HI) frequency distribution has a relatively shallow slope with power-law index -3.6, similar to what is seen from 21-cm maps in nearby galaxies. The stacked absorption spectrum indicates a typical metallicity ~1/20th solar, similar to the mean metallicity of the overall DLA population. The relatively small velocity extent of the low-ionisation lines suggests that ESDLAs do not arise from large-scale flows of neutral gas. The high column densities involved are in turn more similar to what is seen in DLAs associated with gamma-ray burst afterglows (GRB-DLAs), which are known to occur close to star forming regions. This indicates...

  18. The emission probabilities of long range alpha particles from even-even 244-252Cm isotopes

    E-Print Network [OSTI]

    K. P. Santhosh; Sreejith Krishnan; B. Priyanka

    2014-09-02T23:59:59.000Z

    The alpha accompanied cold ternary fission of even-even 244Cm, 246Cm, 248Cm, 250Cm and 252Cm isotopes have been studied by taking the interacting barrier as the sum of Coulomb and proximity potential with the fragments in equatorial configuration. The favorable fragment combinations are obtained from the cold reaction valley plot and by calculating the relative yield for the charge minimized fragments. In the alpha accompanied ternary fission of 244Cm isotope, the highest yield is found for the fragment combination 110Ru+4He+130Sn, which possess near doubly magic nuclei 130Sn. For the ternary fission of 246Cm, 248Cm, 250Cm and 252Cm isotopes with 4He as light charged particle, the highest yield is obtained for the fragment combination with doubly magic nuclei 132Sn as the heavier fragment. The emission probabilities and kinetic energies of long range alpha particle have been computed for the 242,244,246,248Cm isotopes and are found to be in good agreement with the experimental data. The relative yields for the 4He accompanied ternary fission (equatorial and collinear) of 242-252Cm isotopes are compared with the corresponding yield for binary fission. The effect of deformation and orientation of fragments in the 4He accompanied ternary fission of 244-252Cm isotopes are studied. Our study reveals that the ground state deformation has an important role in the alpha accompanied ternary fission as that of shell effect.

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

    E-Print Network [OSTI]

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

    2015-01-01T23:59:59.000Z

    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 der...

  20. A New Mechanism for DNA Alterations Induced by Alpha Particles Such as Those Emitted by Radon and Radon Progeny

    E-Print Network [OSTI]

    Bruce E. Lehnert; Edwin H. Goodwin

    The mechanism(s) by which alpha (a) particles like those emitted from inhaled radon and radon progeny cause their carcinogenic effects in the lung remains unclear. Although direct nuclear traversals by a-particles may be involved in mediating these outcomes, increasing evidence indicates that a particles can cause alterations in DNA in the absence of direct hits to cell nuclei. Using the occurrence of excessive sister chromatid exchanges (SCE) as an index of DNA damage in human lung fibroblasts, we investigated the hypothesis that a-particles may induce DNA damage through the generation of extracellular factors. We have found that a relatively low dose of a-particles can result in the generation of extracellular factors, which, upon transfer to unexposed normal human cells, can cause excessive SCE to an extent equivalent to that observed when the cells are directly irradiated with the same irradiation dose. A short-lived, SCEinducing factor(s) is generated in a-irradiated culture medium containing serum in the absence of cells. A more persistent SCE-inducing factor(s), which can survive freeze-thaw and is heat labile is produced by fibroblasts after exposure to the a-particles. These results indicate that the initiating target for a-particle-induced genetic changes can be larger than a cell's nucleus or even a whole cell. How transmissible factors like those observed here in vitro may extend to the in vivo condition in the context of a-particle-induced carcinogenesis in the respiratory tract remains to be determined. Environ Health Perspect 1 05(Suppl 5):1095-1101 (1997) Key words: alpha particles, radon/radon progeny, indirect radiation effects, high LET radiation,

  1. Multi-isotopic gamma-ray assay system for alpha-contaminated waste

    SciTech Connect (OSTI)

    Close, D.A.; Pratt, J.C.; Caldwell, J.T.; Kunz, W.E.; Schultz, F.J.; Haff, K.W.

    1983-01-01T23:59:59.000Z

    The capability of an existing segmented gamma-ray system is being expanded for the analysis of alpha-contaminated waste drums. A cursory assay of 114 transuranic waste drums of 208-l capacity has been made. Analysis of these data indicates a detection limit better than 100 nCi/g of waste for /sup 237/Np//sup 233/Pa, /sup 239/Pu, /sup 241/Am, /sup 243/Am//sup 239/Np, /sup 60/Co, /sup 125/Sb, /sup 134/ /sup 137/Cs, and /sup 154/Eu. A pending Code of Federal Regulation (10CFR61) stipulates that the nuclear industry quantify not only its transuranic waste, but also certain beta- and gamma-ray-emitting fission products. An assay system based on gamma-ray spectroscopy is the only system that can meet this requirement for the fission products.

  2. 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

    2012-02-29T23:59:59.000Z

    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.

  3. alpha-active iridium isotopes: Topics by E-print Network

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

    CERN Preprints Summary: Currently, 31 actinium, 31 thorium, 28 protactinium, and 23 uranium isotopes have so far been observed; the discovery of these isotopes is discussed. For...

  4. 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

    2015-06-12T23:59:59.000Z

    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.

  5. Isotope effect in the photochemical decomposition of CO{sub 2} (ice) by Lyman-{alpha} radiation

    SciTech Connect (OSTI)

    Yuan Chunqing; Yates, John T. Jr. [Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904 (United States)

    2013-04-21T23:59:59.000Z

    The photochemical decomposition of CO{sub 2}(ice) at 75 K by Lyman-{alpha} radiation (10.2 eV) has been studied using transmission infrared spectroscopy. An isotope effect in the decomposition of the CO{sub 2} molecule in the ice has been discovered, favoring {sup 12}CO{sub 2} photodecomposition over {sup 13}CO{sub 2} by about 10%. The effect is caused by electronic energy transfer from the excited CO{sub 2} molecule to the ice matrix, which favors quenching of the heavier electronically-excited {sup 13}CO{sub 2} molecule over {sup 12}CO{sub 2}. The effect is similar to the Menzel-Gomer-Redhead isotope effect in desorption from adsorbed molecules on surfaces when electronically excited. An enhancement of the rate of formation of lattice-trapped CO and CO{sub 3} species is observed for the photolysis of the {sup 12}CO{sub 2} molecule compared to the {sup 13}CO{sub 2} molecule in the ice. Only 0.5% of the primary photoexcitation results in O-CO bond dissociation to produce trapped-CO and trapped-CO{sub 3} product molecules and the majority of the electronically-excited CO{sub 2} molecules return to the ground state. Here either vibrational relaxation occurs (majority process) or desorption of CO{sub 2} occurs (minority process) from highly vibrationally-excited CO{sub 2} molecules in the ice. The observation of the {sup 12}C/{sup 13}C isotope effect in the Lyman-{alpha} induced photodecomposition of CO{sub 2} (ice) suggests that over astronomical time scales the isotope enrichment effect may distort historical information derived from isotope ratios in space wherever photochemistry can occur.

  6. 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.

    2010-06-23T23:59:59.000Z

    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.

  7. ISOTOPES

    E-Print Network [OSTI]

    Lederer, C. Michael

    2013-01-01T23:59:59.000Z

    rare (0.017%) isotope 36s at enrichments of 70% at a price32). The enrichment of carbon isotopes by C02-carbamatesulfur isotopes by S02-NaHS03 exchange and the enrichment of

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

    E-Print Network [OSTI]

    Bhakta, Viharkumar Satish

    2011-10-21T23:59:59.000Z

    Institute using the K500 superconducting cyclotron following the production reaction Bi-209(?, 2n)At-211 using a thick bismuth target of 500 ?m. We carried out two irradiation experiments where the initial energy of the alpha-particle beam, 80 Me...

  9. Complete kinetic isotope effect description of transition states for acid-catalyzed hydrolyses of methyl. cap alpha. - and. beta. -glucopyranosides

    SciTech Connect (OSTI)

    Bennet, A.J.; Sinnott, M.L.

    1986-11-12T23:59:59.000Z

    The following kinetic isotope effects (k/sub light//k/sub heavy/) have been measured by the isotopic quasi-racemate method for the hydrolyses of methyl ..cap alpha..- and ..beta..-glucopyranosides, respectively in 2.0 M HClO/sub 4/ at 80/sup 0/C (..cap alpha..-D 1.137 +/- 0.007, 1.089 +/- 0.006; ..beta..-D 1.073 +/- 0.003, 1.045 +/- 0.004; ..gamma..-D (C5) 0.987 +/- 0.002, 0.971 +/- 0.003; leaving group d/sub 3/ 1.006 +/- 0.001, 1.015 +/- 0.002; leaving group /sup 18/O 1.026 +/- 0.001, 1.024 +/ +/- 0.002; anomeric /sup 13/C 1.007 +/- 0.001, 1.011 +/- 0.002). In conjunction with studies of the effect of added solutes on the rates of hydrolysis of various aldopyranosyl derivatives, which indicate such reactions are truly unimolecular, and model ring /sup 18/O and ..beta..-deuterium effects, it is possible to locate the dihedral angles about the O5-C1 and C1-C2 bonds at the transition state using these data. If the dihedral angles so derived are used as constraints in calculations using N.L. Allinger's MM2 molecular mechanics program, transition-state structures are obtained. The geometry of these transition states stands in contradiction to the theory of stereoelectronic control.

  10. Targeting of Osseous Sites with Alpha-emitting Ra-223: Comparison with the Beta-emitter Sr-89 in Mice

    SciTech Connect (OSTI)

    Henriksen, Gjermund; Fisher, Darrell R.; Roeske, John C.; Bruland, Oyvind S.; Larsen, Roy H.

    2003-05-16T23:59:59.000Z

    The bone-seeking property of and the potential to irradiate red marrow by the alpha-particle emitter Ra-223 (t1/2 = 11.43 d) were compared to those of the beta-emitter Sr-89 (t1/2 = 50.53 d). Methods: The biodistributions of Ra-223 and Sr-89 were studied in mice. Tissue uptakes were determined at 1 h, 6 h, 1 d, 3 d, and 14 d after intravenous administration. The potential redistribution of progeny from Ra-223 located in bone was investigated. Radiation absorbed doses were calculated for soft tissues and bone. Doses were also estimated for marrow-containing cavities assuming spheric geometries. Results: We found that both Sr-89 and Ra-223 selectively concentrated on bone surfaces relative to soft tissues. The measured bone uptake of Ra-223 was slightly higher than that of Sr-89. At the 24 h time-point, the femur uptake of Ra-223 was 40.1% of the administered activity per gram tissue. The uptake in spleen and most other soft tissues was higher for Ra-223 than for Sr-89. We observed rapid clearance of Ra-223 from soft tissues within the first 24 hours, but the bone surface uptake of Ra-223 increased with time up to 24 h. Among the soft tissues, the spleen had the greatest accumulation and retention of Ra-223. The femur-to-spleen ratio increased with time, from 6.4 at 6 h to 23.7 at 3 days after injections. We found little redistribution of Ra-223 daughter products away from bone (about 2% at 6 h and less than 1% detectable at 3 d). Estimates of dose to marrow-containing cavities showed that the Ra-223 alpha-emitter might have a marrow-sparing advantage compared to beta-emitters due to high linear-energy-transfer and short alpha range targeting osteoid surfaces. The alpha-emitters irradiate a smaller fraction of the marrow-containing volumes--sparing marrow and enhancing survival of marrow cells. At the same time, the bone surfaces receives a therapeutically effective radiation dose. Conclusion: The results of this study indicate that Ra-223 is a promising candidate for high linear-energy-transfer alpha-particle irradiation of cancer cells on bone surfaces. Radium-223 can, together with its daughter radionuclides, deliver an intense and highly localized field of radiation to bone surfaces with substantially less irradiation of healthy bone marrow dose compared to standard, bone-seeking beta-emitters such as Sr-89.

  11. Relative Biologic Effects of Low-Dose-Rate {alpha}-Emitting {sup 227}Th-Rituximab and {beta}-Emitting {sup 90}Y-Tiuexetan-Ibritumomab Versus External Beam X-Radiation

    SciTech Connect (OSTI)

    Dahle, Jostein [Department of Radiation Biology, Norwegian Radium Hospital, Montebello, Oslo (Norway)], E-mail: jostein.dahle@rr-research.no; Bruland, Oyvind S. [University of Oslo and Department of Oncology, Norwegian Radium Hospital, Montebello, Oslo (Norway); Larsen, Roy H. [Department of Radiation Biology, The Norwegian Radium Hospital, Montebello, Oslo (Norway)

    2008-09-01T23:59:59.000Z

    Purpose: To determine the relative biologic effects (RBE) of {alpha}-particle radiation from {sup 227}Th-rituximab and of {beta}-radiation from {sup 90}Y-tiuexetan-ibritumomab (Zevalin) compared with external beam X-radiation in the Raji lymphoma xenograft model. Methods and Materials: Radioimmunoconjugates were administered intravenously in nude mice with Raji lymphoma xenografts at different levels of activity. Absorbed dose to tumor was estimated by separate biodistribution experiments for {sup 227}Th-rituximab and Zevalin. Tumor growth was measured two to three times per week after injection or X-radiation. Treatment-induced increase in growth delay to reach tumor volumes of 500 and 1,000 mm{sup 3}, respectively, was used as an end point. Results: The absorbed radiation dose-rate in tumor was slightly more than 0.1 Gy/d for the first week following injection of {sup 227}Th-rituximab, and thereafter gradually decreased to 0.03 Gy/d at 21 days after injection. For treatment with Zevalin the maximum dose-rate in tumor was achieved already 6 h after injection (0.2 Gy/d), and thereafter decreased to 0.01 Gy/d after 7 days. The relative biologic effect was between 2.5 and 7.2 for {sup 227}Th-rituximab and between 1 and 1.3 for Zevalin. Conclusions: Both at low doses and low-dose-rates, the {sup 227}Th-rituximab treatment was more effective per absorbed radiation dose unit than the two other treatments. The considerable effect at low doses suggests that the best way to administer low-dose-rates, {alpha}-emitting radioimmunoconjugates is via multiple injections.

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

    SciTech Connect (OSTI)

    Yang, Lin [Institute of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Institute of Electronic Engineering, China Academy of Engineering Physics, Mianyang 621900 (China); Tan, Xiaohua; Wan, Xiang; Chen, Lei; Jin, Dazhi; Qian, Muyang [Institute of Electronic Engineering, China Academy of Engineering Physics, Mianyang 621900 (China); Li, Gongping, E-mail: ligp@lzu.edu.cn [Institute of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China)

    2014-04-28T23:59:59.000Z

    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.

  13. First In Vivo Evaluation of Liposome-encapsulated 223Ra as a Potential Alpha-particle-emitting Cancer Therapeutic Agent

    SciTech Connect (OSTI)

    Jonasdottir, Thora J.; Fisher, Darrell R.; Borrebaek, Jorgen; Bruland, Oyvind S.; Larsen, Roy H.

    2006-09-13T23:59:59.000Z

    Liposomes carrying chemotherapeutics have had some success in cancer treatment and may be suitable carriers for therapeutic radionuclides. This study was designed to evaluate the biodistribution of and to estimate the radiation doses from the alpha emitter 223Ra loaded into pegylated liposomes in selected tissues. 223Ra was encapsulated in pegylated liposomal doxorubicin by ionophore-mediated loading. The biodistribution of liposomal 223Ra was compared to free cationic 223Ra in Balb/C mice. We showed that liposomal 223 Ra circulated in the blood with an initial half-time in excess of 24 hours, which agreed well with that reported for liposomal doxorubicin in rodents, while the blood half-time of cationic 223Ra was considerably less than one hour. When liposomal 223 Ra was catabolized, the released 223Ra was either excreted or taken up in the skeleton. This skeletal uptake increased up to 14 days after treatment, but did not reach the level seen with free 223Ra. Pre-treatment with non-radioactive liposomal doxorubicin 4 days in advance lessened the liver uptake of liposomal 223 Ra. Dose estimates showed that the spleen, followed by bone surfaces, received the highest absorbed doses. Liposomal 223 Ra was relatively stable in vivo and may have potential for radionuclide therapy and combination therapy with chemotherapeutic agents.

  14. 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

    2012-01-01T23:59:59.000Z

    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.

  15. The Uncertainties in the 22Ne + alpha-capture Reaction Rates and the Production of the Heavy Magnesium Isotopes in Asymptotic Giant Branch Stars of Intermediate Mass

    E-Print Network [OSTI]

    A. Karakas; M. Lugaro; M. Wiescher; J. Goerres; C. Ugalde

    2006-01-27T23:59:59.000Z

    We present new rates for the 22Ne(alpha, n)25Mg and 22Ne(alpha,gamma)26Mg reactions, with uncertainties that have been considerably reduced compared to previous estimates, and we study how these new rates affect the production of the heavy magnesium isotopes in models of intermediate mass Asymptotic Giant Branch (AGB) stars of different initial compositions. All the models have deep third dredge-up, hot bottom burning and mass loss. Calculations have been performed using the two most commonly used estimates of the 22Ne + alpha rates as well as the new recommended rates, and with combinations of their upper and lower limits. The main result of the present study is that with the new rates, uncertainties on the production of isotopes from Mg to P coming from the 22Ne + alpha-capture rates have been considerably reduced. We have therefore removed one of the important sources of uncertainty to effect models of AGB stars. We have studied the effects of varying the mass-loss rate on nucleosynthesis and discuss other uncertainties related to the physics employed in the computation of stellar structure, such as the modeling of convection, the inclusion of a partial mixing zone and the definition of convective borders. These uncertainties are found to be much larger than those coming from 22Ne + alpha-capture rates, when using our new estimates. Much effort is needed to improve the situation for AGB models.

  16. 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

    2006-05-30T23:59:59.000Z

    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.

  17. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12 Investigation Peer ReviewIronNuclear Physics » Isotopes

  18. Beta delayed alpha emission from the neutron deficient rare earth isotopes {sup 152}Tm and {sup 150}Ho

    SciTech Connect (OSTI)

    Nacher, E. [Instituto de Fisica Corpuscular, CSIC - Univ. de Valencia (Spain); Instituto de Estructura de la Materia, CSIC, Madrid (Spain); Tain, J. L.; Rubio, B.; Algora, A.; Estevez Aguado, M. E.; Gadea, A. [Instituto de Fisica Corpuscular, CSIC - Univ. de Valencia (Spain); Batist, L. [PNPI, Gatchina (Russian Federation); Briz, J. A. [Instituto de Estructura de la Materia, CSIC, Madrid (Spain); Cano-Ott, D. [CIEMAT, Madrid (Spain); Doering, J.; Mukha, I.; Plettner, C.; Roeckl, E. [GSI, Darmstadt (Germany); Gierlik, M.; Janas, Z. [University of Warsaw (Poland)

    2011-11-30T23:59:59.000Z

    The study of beta-delayed proton emission is a well known method to aid the determination of the beta strength distribution in nuclei far from the stability line. At the neutron deficient side of the nuclear chart the process of proton or alpha emission from excited states is energetically allowed when one goes far enough from stability. However, beta-delayed alphas have seldom been measured for nuclei heavier than A = 20. Here we present a study of the beta-delayed alpha-particle emission from {sup 152}Tm and {sup 150}Ho and their importance in the full B(GT) distribution.

  19. Influence of Magnolol on the bystander effect induced by alpha-particle irradiation

    E-Print Network [OSTI]

    Yu, K.N.

    . Introduction Alpha particles emitted from radon and radon progeny contribute the main part of the natural

  20. An alpha scintillation spectrometer

    E-Print Network [OSTI]

    Yates, Ralph Aaron

    1952-01-01T23:59:59.000Z

    phosphor covered light-piper. The ten different energy alpha particles that were emitted from the Uranium were blended into a continuous distribution, there being no apparent difference between this and the thick Thorium distribution. The same was true... investi- gation of the properties of alpha radiation. In his work, the scin- tillations produced by alpha particles impinging on a zinc-sulphide screen were observed and counted visually with the aid of a low power microscope. The scintillations...

  1. The Use of Isotope Dilution Alpha Spectrometry and Liquid Scintillation Counting to Determine Radionuclides in Environmental Samples

    SciTech Connect (OSTI)

    Bylyku, Elida [Center of Applied Nuclear Physics, Tirana University, Tirana (Albania)

    2009-04-19T23:59:59.000Z

    In Albania in recent years it has been of increasing interest to determine various pollutants in the environment and their possible effects on human health. The radiochemical procedure used to identify Pu, Am, U, Th, and Sr radioisotopes in soil, sediment, water, coal, and milk samples is described. The analysis is carried out in the presence of respective tracer solutions and combines the procedure for Pu analysis based on anion exchange, the selective method for Sr isolation based on extraction chromatography using Sr-Spec resin, and the application of the TRU-Spec column for separation of Am fraction. An acid digestion method has been applied for the decomposition of samples. The radiochemical procedure involves the separation of Pu from Th, Am, and Sr by anion exchange, followed by the preconcentration of Am and Sr by coprecipitation with calcium oxalate. Am is separated from Sr by extraction chromatography. Uranium is separated from the bulk elements by liquid-liquid extraction using UTEVA registered resin. Thin sources for alpha spectrometric measurements are prepared by microprecipitation with NdF3. Two International Atomic Energy Agency reference materials were analyzed in parallel with the samples.

  2. Accelerated alpha-decay of 232U isotope achieved by exposure of its aqueous solution with gold nanoparticles to laser radiation

    E-Print Network [OSTI]

    A. V. Simakin; G. A. Shafeev

    2011-12-29T23:59:59.000Z

    Experimental results are presented on laser-induced accelerated alpha-decay of Uranium-232 nuclei under laser exposure of Au nanoparticles in aqueous solutions of its salt. It is demonstrated that the decrease of alpha-activity strongly depends on the peak intensity of the laser radiation in the liquid and is highest at several terawatt per square centimeter. The decrease of alpha-activity of the exposed solutions is accompanied by the deviation of gamma-activities of daughter nuclides of Uranium-232 from their equilibrium values. Possible mechanisms of the laser influence on the alpha-activity are discussed on the basis of the amplification of the electric field of laser wave on metallic nanoparticles.

  3. 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

    2011-12-30T23:59:59.000Z

    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. 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

    2012-01-01T23:59:59.000Z

    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.

  5. Background canceling surface alpha detector

    DOE Patents [OSTI]

    MacArthur, D.W.; Allander, K.S.; Bounds, J.A.

    1996-06-11T23:59:59.000Z

    A background canceling long range alpha detector which is capable of providing output proportional to both the alpha radiation emitted from a surface and to radioactive gas emanating from the surface. The detector operates by using an electrical field between first and second signal planes, an enclosure and the surface or substance to be monitored for alpha radiation. The first and second signal planes are maintained at the same voltage with respect to the electrically conductive enclosure, reducing leakage currents. In the presence of alpha radiation and radioactive gas decay, the signal from the first signal plane is proportional to both the surface alpha radiation and to the airborne radioactive gas, while the signal from the second signal plane is proportional only to the airborne radioactive gas. The difference between these two signals is proportional to the surface alpha radiation alone. 5 figs.

  6. Possible stimulation of nuclear alpha-decay by superfluid helium

    E-Print Network [OSTI]

    A. L. Barabanov

    2009-09-03T23:59:59.000Z

    It is suggested that superfluid helium (condensate of 4-He atoms) may stimulate nuclear alpha-decay in a situation when an alpha-emitter moves through superfluid helium with fine-tuned velocity, so that the backward-emitted alpha-particle is at rest in the laboratory frame. It is shown that the probability of stimulated alpha-decay in this case may be sizable enough to be detected.

  7. 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

    2010-05-18T23:59:59.000Z

    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.

  8. 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)

    2002-07-30T23:59:59.000Z

    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.

  9. Transport of Radioactive Material by Alpha Recoil

    SciTech Connect (OSTI)

    Icenhour, A.S.

    2005-05-19T23:59:59.000Z

    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.

  10. Isotopic studies of the environmental chemistry of lead 

    E-Print Network [OSTI]

    Sugden, Carol Louise

    Lead emitted into the environment, primarily from the combustion of leaded petrol and industrial activities, such as metal smelting and coal burning, retains the isotopic signature of the ores from which it is derived. Accordingly, it is possible...

  11. alpha-emitting radiopharmaceuticals final: Topics by E-print...

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

    Peer Review Report Engineering Websites Summary: ) for Pine Creek Lake, McCurtain County, Oklahoma Prepared by Battelle Memorial Institute Prepared Contract No....

  12. alpha-particle-emitting radioimmunoconjugate 227th-rituximab...

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

    Selahattin 5 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

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

    SciTech Connect (OSTI)

    Robert Hayes, Craig Marianno

    2007-01-01T23:59:59.000Z

    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.

  14. High Flux Isotopes Reactor (HFIR) Cooling Towers Demolition Waste Management

    SciTech Connect (OSTI)

    Pudelek, R. E.; Gilbert, W. C.

    2002-02-26T23:59:59.000Z

    This paper describes the results of a joint initiative between Oak Ridge National Laboratory, operated by UT-Battelle, and Bechtel Jacobs Company, LLC (BJC) to characterize, package, transport, treat, and dispose of demolition waste from the High Flux Isotope Reactor (HFIR), Cooling Tower. The demolition and removal of waste from the site was the first critical step in the planned HFIR beryllium reflector replacement outage scheduled. The outage was scheduled to last a maximum of six months. Demolition and removal of the waste was critical because a new tower was to be constructed over the old concrete water basin. A detailed sampling and analysis plan was developed to characterize the hazardous and radiological constituents of the components of the Cooling Tower. Analyses were performed for Resource Conservation and Recovery Act (RCRA) heavy metals and semi-volatile constituents as defined by 40 CFR 261 and radiological parameters including gross alpha, gross beta, gross gamma, alpha-emitting isotopes and beta-emitting isotopes. Analysis of metals and semi-volatile constituents indicated no exceedances of regulatory limits. Analysis of radionuclides identified uranium and thorium and associated daughters. In addition 60Co, 99Tc, 226Rm, and 228Rm were identified. Most of the tower materials were determined to be low level radioactive waste. A small quantity was determined not to be radioactive, or could be decontaminated. The tower was dismantled October 2000 to January 2001 using a detailed step-by-step process to aid waste segregation and container loading. The volume of waste as packaged for treatment was approximately 1982 cubic meters (70,000 cubic feet). This volume was comprised of plastic ({approx}47%), wood ({approx}38%) and asbestos transite ({approx}14%). The remaining {approx}1% consisted of the fire protection piping (contaminated with lead-based paint) and incidental metal from conduit, nails and braces/supports, and sludge from the basin. The waste, except for the asbestos, was volume reduced via a private contract mechanism established by BJC. After volume reduction, the waste was packaged for rail shipment. This large waste management project successfully met cost and schedule goals.

  15. White organic light-emitting diodes with an ultra-thin premixed emitting layer

    E-Print Network [OSTI]

    Jeon, T; Tondelier, Denis; Bonnassieux, Yvan; Forget, Sebastien; Chenais, Sebastien; Ishow, Elena

    2014-01-01T23:59:59.000Z

    We described an approach to achieve fine color control of fluorescent White Organic Light-Emitting Diodes (OLED), based on an Ultra-thin Premixed emitting Layer (UPL). The UPL consists of a mixture of two dyes (red-emitting 4-di(4'-tert-butylbiphenyl-4-yl)amino-4'-dicyanovinylbenzene or fvin and green-emitting 4-di(4'-tert-butylbiphenyl-4-yl)aminobenzaldehyde or fcho) premixed in a single evaporation cell: since these two molecules have comparable structures and similar melting temperatures, a blend can be evaporated, giving rise to thin films of identical and reproducible composition compared to those of the pre-mixture. The principle of fine color tuning is demonstrated by evaporating a 1-nm-thick layer of this blend within the hole-transport layer (4,4'-bis[N-(1-naphtyl)-N-phenylamino]biphenyl (\\alpha-NPB)) of a standard fluorescent OLED structure. Upon playing on the position of the UPL inside the hole-transport layer, as well as on the premix composition, two independent parameters are available to finel...

  16. A new method of alpha ray measurement using a Quadrupole Mass Spectrometer

    E-Print Network [OSTI]

    Y. Iwata; Y. Inoue; M. Minowa

    2007-04-16T23:59:59.000Z

    We propose a new method of alpha($\\alpha$)-ray measurement that detects helium atoms with a Quadrupole Mass Spectrometer(QMS). A demonstration is undertaken with a plastic-covered $^{241}$Am $\\alpha$-emitting source to detect $\\alpha$-rays stopped in the capsule. We successfully detect helium atoms that diffuse out of the capsule by accumulating them for one to 20 hours in a closed chamber. The detected amount is found to be proportional to the accumulation time. Our method is applicable to probe $\\alpha$-emitting radioactivity in bulk material.

  17. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1991-05-08T23:59:59.000Z

    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.

  18. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

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

    1993-01-01T23:59:59.000Z

    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.

  19. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1993-03-30T23:59:59.000Z

    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.

  20. from Isotope Production Facility

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

    Cancer-fighting treatment gets boost from Isotope Production Facility April 13, 2012 Isotope Production Facility produces cancer-fighting actinium 2:32 Isotope cancer treatment...

  1. Toward ZnO Light Emitting Diode

    E-Print Network [OSTI]

    Liu, Jianlin

    2008-01-01T23:59:59.000Z

    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

  2. Isotopically controlled semiconductors

    E-Print Network [OSTI]

    Haller, Eugene E.

    2006-01-01T23:59:59.000Z

    16 Isotopically Controlled Semiconductors Eugene E. Hallerof isotopically engineered semiconductors; for outstandingisotopically controlled semiconductor crystals. This article

  3. Infrared emitting device and method

    DOE Patents [OSTI]

    Kurtz, Steven R. (Albuquerque, NM); Biefeld, Robert M. (Albuquerque, NM); Dawson, L. Ralph (Albuquerque, NM); Howard, Arnold J. (Albuquerque, NM); Baucom, Kevin C. (Albuquerque, NM)

    1997-01-01T23:59:59.000Z

    An infrared emitting device and method. The infrared emitting device comprises a III-V compound semiconductor substrate upon which are grown a quantum-well active region having a plurality of quantum-well layers formed of a ternary alloy comprising InAsSb sandwiched between barrier layers formed of a ternary alloy having a smaller lattice constant and a larger energy bandgap than the quantum-well layers. The quantum-well layers are preferably compressively strained to increase the threshold energy for Auger recombination; and a method is provided for determining the preferred thickness for the quantum-well layers. Embodiments of the present invention are described having at least one cladding layer to increase the optical and carrier confinement in the active region, and to provide for waveguiding of the light generated within the active region. Examples have been set forth showing embodiments of the present invention as surface- and edge-emitting light emitting diodes (LEDs), an optically-pumped semiconductor laser, and an electrically-injected semiconductor diode laser. The light emission from each of the infrared emitting devices of the present invention is in the midwave infrared region of the spectrum from about 2 to 6 microns.

  4. 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

    2015-06-11T23:59:59.000Z

    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.

  5. 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

    2015-01-01T23:59:59.000Z

    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.

  6. 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)

    1998-01-01T23:59:59.000Z

    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.

  7. Broadband light-emitting diode

    DOE Patents [OSTI]

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

    1998-01-01T23:59:59.000Z

    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.

  8. Broadband light-emitting diode

    DOE Patents [OSTI]

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

    1998-07-14T23:59:59.000Z

    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.

  9. Infrared emitting device and method

    DOE Patents [OSTI]

    Kurtz, S.R.; Biefeld, R.M.; Dawson, L.R.; Howard, A.J.; Baucom, K.C.

    1997-04-29T23:59:59.000Z

    The infrared emitting device comprises a III-V compound semiconductor substrate upon which are grown a quantum-well active region having a plurality of quantum-well layers formed of a ternary alloy comprising InAsSb sandwiched between barrier layers formed of a ternary alloy having a smaller lattice constant and a larger energy bandgap than the quantum-well layers. The quantum-well layers are preferably compressively strained to increase the threshold energy for Auger recombination; and a method is provided for determining the preferred thickness for the quantum-well layers. Embodiments of the present invention are described having at least one cladding layer to increase the optical and carrier confinement in the active region, and to provide for waveguiding of the light generated within the active region. Examples have been set forth showing embodiments of the present invention as surface- and edge-emitting light emitting diodes (LEDs), an optically-pumped semiconductor laser, and an electrically-injected semiconductor diode laser. The light emission from each of the infrared emitting devices of the present invention is in the midwave infrared region of the spectrum from about 2 to 6 microns. 8 figs.

  10. Apparatus for detecting alpha radiation in difficult access areas

    DOE Patents [OSTI]

    Steadman, Peter (Santa Fe, NM); MacArthur, Duncan W. (Los Alamos, NM)

    1997-09-02T23:59:59.000Z

    An electrostatic alpha radiation detector for measuring alpha radiation emitted from inside an enclosure comprising an electrically conductive expandable electrode for insertion into the enclosure. After insertion, the electrically conductive expandable electrode is insulated from the enclosure and defines a decay cavity between the electrically conductive expandable electrode and the enclosure so that air ions generated in the decay cavity are electrostatically captured by the electrically conductive expandable electrode and the enclosure when an electric potential is applied between the electrically conductive expandable electrode and the enclosure. Indicator means are attached to the electrically conductive expandable electrode for indicating an electrical current produced by generation of the air ions generated in the decay cavity by collisions between air molecules and the alpha particles emitted from the enclosure. A voltage source is connected between the indicator means and the electrically conductive enclosure for creating an electric field between the electrically conductive expandable electrode and the enclosure.

  11. Apparatus for detecting alpha radiation in difficult access areas

    DOE Patents [OSTI]

    Steadman, P.; MacArthur, D.W.

    1997-09-02T23:59:59.000Z

    An electrostatic alpha radiation detector for measuring alpha radiation emitted from inside an enclosure comprising an electrically conductive expandable electrode for insertion into the enclosure is disclosed. After insertion, the electrically conductive expandable electrode is insulated from the enclosure and defines a decay cavity between the electrically conductive expandable electrode and the enclosure so that air ions generated in the decay cavity are electrostatically captured by the electrically conductive expandable electrode and the enclosure when an electric potential is applied between the electrically conductive expandable electrode and the enclosure. Indicator means are attached to the electrically conductive expandable electrode for indicating an electrical current produced by generation of the air ions generated in the decay cavity by collisions between air molecules and the alpha particles emitted from the enclosure. A voltage source is connected between the indicator means and the electrically conductive enclosure for creating an electric field between the electrically conductive expandable electrode and the enclosure. 4 figs.

  12. 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

  13. Quantum Dot Light Emitting Diode

    SciTech Connect (OSTI)

    Kahen, Keith

    2008-07-31T23:59:59.000Z

    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.

  14. Quantum Dot Light Emitting Diode

    SciTech Connect (OSTI)

    Keith Kahen

    2008-07-31T23:59:59.000Z

    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.

  15. 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)

    2012-04-17T23:59:59.000Z

    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.

  16. White light-emitting organic electroluminescent devices

    DOE Patents [OSTI]

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

    2006-06-20T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    White emitting polyfluorene functionalized with azide hybridized on near-UV light emitting diode generation using CdSe/ZnS core-shell nanocrystals hybridized with InGaN/GaN light emitting diodesGaN/conjugated polymer hybrid light-emitting diodes," Appl. Phys. Lett. 70, 2664-2666 (1997). 9. H. V. Demir, S

  18. Visible light emitting vertical cavity surface emitting lasers

    DOE Patents [OSTI]

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

    1995-06-27T23:59:59.000Z

    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.

  19. Visible light emitting vertical cavity surface emitting lasers

    DOE Patents [OSTI]

    Bryan, Robert P. (Boulder, CO); Olbright, Gregory R. (Boulder, CO); Lott, James A. (Albuquerque, NM); Schneider, Jr., Richard P. (Albuquerque, NM)

    1995-01-01T23:59:59.000Z

    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-y).sub.1-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.

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

    E-Print Network [OSTI]

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

    2007-11-15T23:59:59.000Z

    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.

  1. Isotope Science and Production

    E-Print Network [OSTI]

    Isotope Science and Production 35 years of experience in isotope production, processing, and applications. Llllll Committed to the safe and reliable production of radioisotopes, products, and services nuclear materials in trucks and cargo containers. Isotopes for Threat Reduction Isotope production at Los

  2. Stable isotope studies

    SciTech Connect (OSTI)

    Ishida, T.

    1992-01-01T23:59:59.000Z

    The research has been in four general areas: (1) correlation of isotope effects with molecular forces and molecular structures, (2) correlation of zero-point energy and its isotope effects with molecular structure and molecular forces, (3) vapor pressure isotope effects, and (4) fractionation of stable isotopes. 73 refs, 38 figs, 29 tabs.

  3. alpha cap alpha: Topics by E-print Network

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

    present review provides an update on alphas measurements from the past year. W. J. Stirling 1997-09-23 3 ALPHA OMEGA ALPHA National Honor Medical Society Biology and Medicine...

  4. alpha pkc alpha: Topics by E-print Network

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

    present review provides an update on alphas measurements from the past year. W. J. Stirling 1997-09-23 3 ALPHA OMEGA ALPHA National Honor Medical Society Biology and Medicine...

  5. Event counting alpha detector

    DOE Patents [OSTI]

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

    1996-08-27T23:59:59.000Z

    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.

  6. Event counting alpha detector

    DOE Patents [OSTI]

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

    1996-01-01T23:59:59.000Z

    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.

  7. Sandia National Laboratories: light-emitting diode

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

    light-emitting diode Sandian Receives the Illuminating Engineering Society of North America, South Region Technical Award On December 12, 2014, in Capabilities, Energy, Energy...

  8. 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

    1994-01-01T23:59:59.000Z

    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...

  9. 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

    1994-01-01T23:59:59.000Z

    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...

  10. The effects of alpha particle irradiation on stainless steel

    E-Print Network [OSTI]

    Shipp, John Douglas

    1999-01-01T23:59:59.000Z

    and an approximation based on the first year's fluence. . . . . . . . . 17 CHAPTER I INTRODUCTION The storage of Weapons Grade Plutonium (WGPu) pits has prompted this study of the effects of alpha particle irradiation on stainless steel. Previous studies of alpha... and properties of WGPu. ISOTOPE Pu-239 Pu-240 P0-241 Density* Crystal Structure* ATOMIC ABD. (/o) 94. 0 5. 8 0. 2 15. 7 g/cm' BCC 'Note: The density and crystal structure of elemental plutonium is 19. 7 g/cm' and FCC, respectively...

  11. Detection of the Natural Alpha Decay of Tungsten

    E-Print Network [OSTI]

    C. Cozzini; G. Angloher; C. Bucci; F. von Feilitzsch; D. Hauff; S. Henry; Th. Jagemann; J. Jochum; H. Kraus; B. Majorovits; V. Mikhailik; J. Ninkovic; F. Petricca; W. Potzel; F. Proebst; Y. Ramachers; W. Rau; M. Razeti; W. Seidel; M. Stark; L. Stodolsky; A. J. B. Tolhurst; W. Westphal; H. Wulandari

    2004-10-26T23:59:59.000Z

    The natural alpha decay of 180W has been unambiguously detected for the first time. The alpha peak is found in a (gamma,beta and neutron)-free background spectrum. This has been achieved by the simultaneous measurement of phonon and light signals with the CRESST cryogenic detectors. A half-life of T1/2 = (1.8 +- 0.2) x 10^18 y and an energy release of Q = (2516.4 +- 1.1 (stat.) +- 1.2 (sys.)) keV have been measured. New limits are also set on the half-lives of the other naturally occurring tungsten isotopes.

  12. 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)

    2010-12-28T23:59:59.000Z

    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.

  13. Light emitting device having peripheral emissive region

    DOE Patents [OSTI]

    Forrest, Stephen R

    2013-05-28T23:59:59.000Z

    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.

  14. On the Alpha Activity of Natural Tungsten Isotopes

    E-Print Network [OSTI]

    F. A. Danevich A; A. Sh. Georgadze A; V. V. Kobychev A; S. S. Nagorny A; A. S. Nikolaiko A; W

    The indication for the ? decay of 180W with a half-life T ? 1/2 =1.1+0.8 ?0.4(stat)±0.3(syst)×1018 yr has been observed for the first time with the help of the super-low background 116CdWO4 crystal scintillators. In conservative approach the lower limit on half-life of 180W has been established as T ? 1/2 (180W) ? 0.7×1018 yr at 90 % C.L. Besides, new T ? 1/2 bounds were set for ? decay of

  15. 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

    2001-04-21T23:59:59.000Z

    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.

  16. 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

    2010-08-12T23:59:59.000Z

    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.

  17. 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

    2010-09-17T23:59:59.000Z

    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.

  18. Stable blue phosphorescent organic light emitting devices

    DOE Patents [OSTI]

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

    2014-08-26T23:59:59.000Z

    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.

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

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

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

  20. 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...

  1. Highly efficient blue organic light emitting devices with indium...

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

    efficient blue organic light emitting devices with indium-free transparent anode on flexible substrates. Highly efficient blue organic light emitting devices with indium-free...

  2. An Infrared Spectral Database for Detection of Gases Emitted...

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

    Database for Detection of Gases Emitted by Biomass Burning. An Infrared Spectral Database for Detection of Gases Emitted by Biomass Burning. Abstract: We report the construction of...

  3. array lasers emitting: Topics by E-print Network

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

    Array and Graphene Hybrid Light Emitting Diodes Jung Min Lee, Jae a class of light emitting diode (LED) with interesting mechanical, optical, and electrical characteristics,...

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

    E-Print Network [OSTI]

    J. C. Pei; F. R. Xu

    2007-02-01T23:59:59.000Z

    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.

  5. Hybrid isotope separation scheme

    DOE Patents [OSTI]

    Maya, J.

    1991-06-18T23:59:59.000Z

    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.

  6. Hybrid isotope separation scheme

    DOE Patents [OSTI]

    Maya, Jakob (Brookline, MA)

    1991-01-01T23:59:59.000Z

    A method of 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.

  7. 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.

    1999-09-01T23:59:59.000Z

    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.

  8. Stable isotope enrichment

    ScienceCinema (OSTI)

    Egle, Brian

    2014-07-15T23:59:59.000Z

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

  9. Isotopically controlled semiconductors

    E-Print Network [OSTI]

    Haller, E.E.

    2004-01-01T23:59:59.000Z

    and phonons in semiconductors,” J. Non-Cryst. Solids 141 (LVM) Spectroscopy of Semiconductors,” Mat. Res. Soc. Symp.Isotopically Engineered Semiconductors – New Media for the

  10. Stable isotope enrichment

    SciTech Connect (OSTI)

    Egle, Brian

    2014-07-14T23:59:59.000Z

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

  11. Discovery of the Tungsten Isotopes

    E-Print Network [OSTI]

    A. Fritsch; J. Q. Ginepro; M. Heim; A. Schuh; A. Shore; M. Thoennessen

    2009-03-25T23:59:59.000Z

    Thirty-five tungsten 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 Titanium Isotopes

    E-Print Network [OSTI]

    D. Meierfrankenfeld; M. Thoennessen

    2010-09-08T23:59:59.000Z

    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.

  13. Discovery of the Tin Isotopes

    E-Print Network [OSTI]

    S. Amos; M. Thoennessen

    2010-09-08T23:59:59.000Z

    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.

  14. Discovery of the tungsten isotopes

    SciTech Connect (OSTI)

    Fritsch, A.; Ginepro, J.Q.; Heim, M.; Schuh, A.; Shore, A. [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Thoennessen, M. [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)], E-mail: thoennessen@nscl.msu.edu

    2010-05-15T23:59:59.000Z

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

  15. Discovery of the Tungsten Isotopes

    E-Print Network [OSTI]

    Fritsch, A; Heim, M; Schuh, A; Shore, A; Thoennessen, M

    2009-01-01T23:59:59.000Z

    Thirty-five tungsten 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. Side-emitting fiber optic position sensor

    DOE Patents [OSTI]

    Weiss, Jonathan D. (Albuquerque, NM)

    2008-02-12T23:59:59.000Z

    A side-emitting fiber optic position sensor and method of determining an unknown position of an object by using the sensor. In one embodiment, a concentrated beam of light source illuminates the side of a side-emitting fiber optic at an unknown axial position along the fiber's length. Some of this side-illuminated light is in-scattered into the fiber and captured. As the captured light is guided down the fiber, its intensity decreases due to loss from side-emission away from the fiber and from bulk absorption within the fiber. By measuring the intensity of light emitted from one (or both) ends of the fiber with a photodetector(s), the axial position of the light source is determined by comparing the photodetector's signal to a calibrated response curve, look-up table, or by using a mathematical model. Alternatively, the side-emitting fiber is illuminated at one end, while a photodetector measures the intensity of light emitted from the side of the fiber, at an unknown position. As the photodetector moves further away from the illuminated end, the detector's signal strength decreases due to loss from side-emission and/or bulk absorption. As before, the detector's signal is correlated to a unique position along the fiber.

  17. QCD Studies and alpha_s Measurements at LEP

    E-Print Network [OSTI]

    Stefan Soldner-Rembold

    2004-11-01T23:59:59.000Z

    The LEP experiments have measured event shapes using data taken at e+e- center-of-mass energies ranging from 91 GeV to 209 GeV. Using the final LEP event shape measurements, a combined value of the strong coupling constant alpha_s(M_Z) has been extracted. Events with photon radiation have been used to extend the measurements to lower center-of-mass energies sqrt(s') to study the running of alpha_s. Alternative alpha_s measurements using four-jet rates have also been performed.

  18. Visible light surface emitting semiconductor laser

    DOE Patents [OSTI]

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

    1993-01-01T23:59:59.000Z

    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. (Carbon isotope fractionation inplants)

    SciTech Connect (OSTI)

    O'Leary, M.H.

    1990-01-01T23:59:59.000Z

    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.

  20. Binding Energies and Radii of the Nuclei with N >=Z in an Alpha-Cluster Model

    E-Print Network [OSTI]

    G. K. Nie

    2008-07-01T23:59:59.000Z

    Using the surface tension energy put in dependence on the number of alpha-clusters in the core in a phenomenological model representing a nucleus as a core and a nuclear molecule on its surface leads to widening the number of isotopes to be described from the narrow strip of beta-stability to the isotopes with N >= Z. The number of alpha-clusters in the molecule is obtained from the analysis of experimental binding energies and the specific density of the core binding energy \\rho and the radii are calculated. It is shown that for the isotopes of one Z with growing A the number of alpha-clusters of the molecule decreases mostly to 3 and \\rho increases to reach a saturation value within \\rho = 2.5 \\div 2.7 MeV/fm^3 at the beta - stable isotopes, so the narrow strip of the binding energies of the beta - stable isotopes with Z <= 84 is outlined by a function of one variable Z.

  1. 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)

    1988-01-01T23:59:59.000Z

    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.

  2. Photochemical isotope separation

    DOE Patents [OSTI]

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

    1987-01-01T23:59:59.000Z

    A process 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.

  3. Photochemical isotope separation

    DOE Patents [OSTI]

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

    1987-04-28T23:59:59.000Z

    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.

  4. alpha-emitting radioisotopes production: Topics by E-print Network

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

    deduplication and compression with the cloud to reduce the storage footprint as well as CapEx and OpEx costs Chaudhuri, Surajit 255 Product Information Transparent Engineering...

  5. antibody alpha-particle-emitting radionuclides: Topics by E-print...

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

    21 22 23 24 25 Next Page Last Page Topic Index 41 COUNCIL ON RADIONUCLIDES AND RADIOPHARMACEUTICALS POSITION PAPER ON MIXED WASTE CiteSeer Summary: The Council on Radionuclides...

  6. alpha-emitting radionuclides bismuth-213: Topics by E-print Network

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

    4 sup 0 K, sup 5 sup 3 Mn, sup 6 sup 0 Fe, sup 8 sup 7 Rb, sup 9 sup 3 Zr, sup 9 sup 8 Tc, sup 1 sup 0 sup 7 Pd, sup 1 sup 2 sup 9 I, sup 1 sup 3 sup 5 Cs, sup 1 sup 4 sup 6 Sm,...

  7. DOSES IN HUMAN ORGANS DUE TO ALPHA, BETA AND GAMMA RADIATIONS EMITTED BY THORON PROGENY IN

    E-Print Network [OSTI]

    Yu, K.N.

    progeny than that of the radon progeny. It is interesting to note that after the lungs, where body. The DCF to other organs was obtained as 20 mSv WLM­1 , which is larger than the DCF for radon progeny, which was 13 mSv WLM­1 . This is a consequence of the longer half-life of the relevant thoron

  8. alpha-particle-emitting 211at-labeled trastuzumab: Topics by...

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

    10 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  9. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurTheBrookhaven National LaboratoryJeffreyMs.Princeton PlasmaU.S. DOE Office of

  10. 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.)

    2002-01-01T23:59:59.000Z

    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.

  11. Ultra-high-resolution alpha spectrometry for nuclear forensics and safeguards applications

    SciTech Connect (OSTI)

    Bacrania, Minesh K [Los Alamos National Laboratory; Croce, Mark [Los Alamos National Laboratory; Bond, Evelyn [Los Alamos National Laboratory; Dry, Donald [Los Alamos National Laboratory; Moody, W. Allen [Los Alamos National Laboratory; Lamont, Stephen [Los Alamos National Laboratory; Rabin, Michael [Los Alamos National Laboratory; Rim, Jung [Los Alamos National Laboratory; Smith, Audrey [Los Alamos National Laboratory; Beall, James [NIST-BOULDER; Bennett, Douglas [NIST-BOULDER; Kotsubo, Vincent [NIST-BOULDER; Horansky, Robert [NIST-BOULDER; Hilton, Gene [NIST-BOULDER; Schmidt, Daniel [NIST-BOULDER; Ullom, Joel [NIST-BOULDER; Cantor, Robin [STAR CRYOELECTRONICS

    2010-01-01T23:59:59.000Z

    We will present our work on the development of ultra-high-resolution detectors for alpha particle spectrometry. These detectors, based on superconducting transition-edge sensors, offer energy resolution that is five to ten times better than conventional silicon detectors. Using these microcalorimeter detectors, the isotopic composition of mixed-actinide samples can be determined rapidly without the need for actinide separation chemistry to isolate each element, or mass spectrometry to separate isotopic signatures that can not be resolved using traditional alpha spectrometry (e.g. Pu-239/Pu-240, or Pu-238/Am-241). This paper will cover the detector and measurement system, actinide source preparation, and the quantitative isotopic analysis of a number of forensics- and safeguards-relevant radioactive sources.

  12. Physics with Rare Isotope Beams

    SciTech Connect (OSTI)

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

    2013-11-08T23:59:59.000Z

    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.

  13. Can a many-nucleon structure be visible in bremsstrahlung emission during $\\alpha$ decay?

    E-Print Network [OSTI]

    Maydanyuk, Sergei P; Zou, Li-Ping

    2015-01-01T23:59:59.000Z

    We analyze if the nucleon structure of the $\\alpha$ decaying nucleus can be visible in the experimental bremsstrahlung spectra of the emitted photons which accompany such a decay. We develop a new formalism of the bremsstrahlung model taking into account distribution of nucleons in the $\\alpha$ decaying nuclear system. We conclude the following: (1) After inclusion of the nucleon structure into the model the calculated bremsstrahlung spectrum is changed very slowly for a majority of the $\\alpha$ decaying nuclei. However, we have observed that visible changes really exist for the $^{106}{\\rm Te}$ nucleus ($Q_{\\alpha}=4.29$ MeV, $T_{1/2}$=70 mks) even for the energy of the emitted photons up to 1 MeV. This nucleus is a good candidate for future experimental study of this task. (2) Inclusion of the nucleon structure into the model increases the bremsstrahlung probability of the emitted photons. (3) We find the following tendencies for obtaining the nuclei, which have bremsstrahlung spectra more sensitive to the ...

  14. Isotopic Scaling and the Symmetry Energy in Spectator Fragmentation

    E-Print Network [OSTI]

    Auger, G; Begemann-Blaich, M L; Bellaize, N; Bittiger, R; Bocage, F; Borderie, B; Bougault, R; Bouriquet, B; Charvet, J L; Chbihi, A; Dayras, R; Durand, D; Frankland, J D; Galíchet, E; Gourio, D; Guinet, D; Hudan, S; Imme, G; Lautesse, P; Lavaud, F; Legrain, R; López, O; Lynen, U; Müller, W F J; Nalpas, L; Orth, H; Plagnol, E; Raciti, G; Rosato, E; Saija, A; Schwarz, C; Seidel, W; Sfienti, C; Tamain, B; Trautmann, W; Trzcinski, A; Turzó, K; Vient, E; Vigilante, M; Volant, C; Zwieglinski, B; Botvina, A S; The INDRA Collaboration

    2004-01-01T23:59:59.000Z

    Isotopic effects in the fragmentation of excited target residues following collisions of $^{12}$C on $^{112,124}$Sn at incident energies of 300 and 600 MeV per nucleon were studied with the INDRA 4$\\pi$ detector. The measured yield ratios for light particles and fragments with atomic number $Z \\leq$ 5 obey the exponential law of isotopic scaling. The deduced scaling parameters decrease with increasing centrality to values as low as $\\alpha = 0.25 \\pm 0.02$ for the central event group at 600 MeV per nucleon. Symmetry term coefficients, deduced from these data within the statistical description of isotopic scaling, are near $\\gamma =$ 25 MeV for peripheral and $\\gamma <$ 10 MeV for central collisions.

  15. Photon/electron-rejecting alpha liquid scintillation (PERALS{reg_sign}) spectrometry: A review

    SciTech Connect (OSTI)

    McDowell, J.W.

    1992-12-31T23:59:59.000Z

    Alpha spectrometry by liquid scintillation has become a practical reality within the last three to four years. The present ability to identify and reject virtually all pulses from beta and gamma radiation (<99.95) and to obtain useful (5%) resolution of alpha energies allows alpha liquid-scintillation spectrometry to be viewed in a different perspective than formerly. Instrumentation and reagents now are available so that radiochemical laboratories can consider alpha liquid scintillation as a useful addition to their present methods of alpha counting and spectrometry. Coupling this instrumentation with extractive scintillators that have efficient light output and high liquid-liquid extraction selectivity for a given radionuclide produces a system that allows both great sensitivity and high accuracy in alpha counting. Thus the method is applicable to both the detection of low levels of activity in the environment (0.001 cpm) and to the accurate determination of the amount of an alpha-emitting radionuclide for accountability purposes (accuracy limited only by sampling errors). This article attempts to survey the known applications of alpha liquid scintillation and preview some additional applications that are just now developing.

  16. Long range alpha particle detector

    DOE Patents [OSTI]

    MacArthur, D.W.; Wolf, M.A.; McAtee, J.L.; Unruh, W.P.; Cucchiara, A.L.; Huchton, R.L.

    1993-02-02T23:59:59.000Z

    An alpha particle detector capable of detecting alpha radiation from distant sources. In one embodiment, a high voltage is generated in a first electrically conductive mesh while a fan draws air containing air molecules ionized by alpha particles through an air passage and across a second electrically conductive mesh. The current in the second electrically conductive mesh can be detected and used for measurement or alarm. The detector can be used for area, personnel and equipment monitoring.

  17. Nuclear Alpha-Particle Condensates

    E-Print Network [OSTI]

    T. Yamada; Y. Funaki; H. Horiuchi; G. Roepke; P. Schuck; A. Tohsaki

    2011-03-21T23:59:59.000Z

    The $\\alpha$-particle condensate in nuclei is a novel state described by a product state of $\\alpha$'s, all with their c.o.m. in the lowest 0S orbit. We demonstrate that a typical $\\alpha$-particle condensate is the Hoyle state ($E_{x}=7.65$ MeV, $0^+_2$ state in $^{12}$C), which plays a crucial role for the synthesis of $^{12}$C in the universe. The influence of antisymmentrization in the Hoyle state on the bosonic character of the $\\alpha$ particle is discussed in detail. It is shown to be weak. The bosonic aspects in the Hoyle state, therefore, are predominant. It is conjectured that $\\alpha$-particle condensate states also exist in heavier $n\\alpha$ nuclei, like $^{16}$O, $^{20}$Ne, etc. For instance the $0^+_6$ state of $^{16}$O at $E_{x}=15.1$ MeV is identified from a theoretical analysis as being a strong candidate of a $4\\alpha$ condensate. The calculated small width (34 keV) of $0^+_6$, consistent with data, lends credit to the existence of heavier Hoyle-analogue states. In non-self-conjugated nuclei such as $^{11}$B and $^{13}$C, we discuss candidates for the product states of clusters, composed of $\\alpha$'s, triton's, and neutrons etc. The relationship of $\\alpha$-particle condensation in finite nuclei to quartetting in symmetric nuclear matter is investigated with the help of an in-medium modified four-nucleon equation. A nonlinear order parameter equation for quartet condensation is derived and solved for $\\alpha$ particle condensation in infinite nuclear matter. The strong qualitative difference with the pairing case is pointed out.

  18. High-purity, isotopically enriched bulk silicon

    E-Print Network [OSTI]

    2004-01-01T23:59:59.000Z

    Russia. The stated isotope enrichments are summarized inenrichments >99% have been achieved for each isotope andthe enrichment is highest, are presented. isotope at. % nat.

  19. 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. (Waterloo); (Kyungpook National University)

    2012-10-25T23:59:59.000Z

    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.

  20. 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)

    2011-03-22T23:59:59.000Z

    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.

  1. Highly Efficient Silicon Light Emitting Diode

    E-Print Network [OSTI]

    Leminh Holleman Wallinga; P. Leminh; J. Holleman; H. Wallinga

    2000-01-01T23:59:59.000Z

    In this paper, we describe the fabrication, using standard silicon processing techniques, of silicon light-emitting diodes (LED) that efficiently emit photons with energy around the silicon bandgap. The improved efficiency had been explained by the spatial confinement of charge carriers due to a local strain field that is formed by dislocation loop arrays. The dependence of device electroluminescent properties on the annealing conditions is carefully examined as a high temperature process has profound influence on these dislocations. Increased luminescent intensity at higher device temperature, together with pure diffusion current conduction mechanism evidently shows the influence of the dislocation loops. The electrical properties of the diode are reasonable with low leakage reverse current.

  2. Thermo-electrically pumped semiconductor light emitting diodes

    E-Print Network [OSTI]

    Santhanam, Parthiban

    2014-01-01T23:59:59.000Z

    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. ...

  3. Water Cooling of High Power Light Emitting Diode Henrik Srensen

    E-Print Network [OSTI]

    Berning, Torsten

    Water Cooling of High Power Light Emitting Diode Henrik Sørensen Department of Energy Technology and product lifetime. The high power Light Emitting Diodes (LED) belongs to the group of electronics

  4. 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

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

    SciTech Connect (OSTI)

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

    1988-08-09T23:59:59.000Z

    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.

  6. Measurements of the Cerenkov light emitted by a TeO2 crystal

    E-Print Network [OSTI]

    F. Bellini; N. Casali; I. Dafinei; M. Marafini; S. Morganti; F. Orio; D. Pinci; M. Vignati; C. Voena

    2012-12-12T23:59:59.000Z

    Bolometers have proven to be good instruments to search for rare processes because of their excellent energy resolution and their extremely low intrinsic background. In this kind of detectors, the capability of discriminating alpha particles from electrons represents an important aspect for the background reduction. One possibility for obtaining such a discrimination is provided by the detection of the Cerenkov light which, at the low energies of the natural radioactivity, is only emitted by electrons. In this paper, the results of the analysis of the light emitted by a TeO2 crystal at room temperature when transversed by a cosmic ray are reported. Light is promptly emitted after the particle crossing and a clear evidence of its directionality is also found. These results represent a strong indication that Cerenkov light is the main, if not even the only, component of the light signal in a TeO2 crystal. They open the possibility to make large improvements in the performance of experiments based on this kind of materials

  7. Masses and Radii of the Nuclei with N>=Z in an Alpha-Cluster Model

    E-Print Network [OSTI]

    G. K. Nie

    2009-11-05T23:59:59.000Z

    In the framework of a recently developed alpha-cluster model a nucleus is represented as a core (alpha-cluster liquid drop with dissolved excess neutron pairs in it) and a nuclear molecule on its surface. From analysis of experimental nuclear binding energies one can find the number of alpha-clusters in the molecule and calculate the nuclear charge radii. It was shown that for isotopes of one Z with growing A the number of alpha-clusters in the molecule decreases to three, which corresponds to the nucleus 12C for even Z and 15N for odd Z, and the specific density of the core binding energy \\rho grows and reaches its saturation value. In this paper it is shown that the value \\rho=2.55 MeV/fm^3 explains the particular number of excess neutrons in stable nuclei.

  8. 12.6 keV Kr K-alpha X-ray Source For High Energy Density Physics Experiments

    SciTech Connect (OSTI)

    Kugland, N; Constantin, C G; Niemann, C; Neumayer, P; Chung, H; Doppner, T; Kemp, A; Glenzer, S H; Girard, F

    2008-04-22T23:59:59.000Z

    A high contrast 12.6 keV Kr K{alpha} source has been demonstrated on the petawatt-class Titan laser facility. The contrast ratio (K{alpha} to continuum) is 65, with a competitive ultra short pulse laser to x-ray conversion efficiency of 10{sup -5}. Filtered shadowgraphy indicates that the Kr K{alpha} and K{beta} x-rays are emitted from a roughly 1 x 2 mm emission volume, making this source suitable for area backlighting and scattering. Spectral calculations indicate a typical bulk electron temperature of 50-70 eV (i.e. mean ionization state 13-16), based on the observed ratio of K{alpha} to K{beta}. Kr gas jets provide a debris-free high energy K{alpha} source for time-resolved diagnosis of dense matter.

  9. Transportation of medical isotopes

    SciTech Connect (OSTI)

    Nielsen, D.L.

    1997-11-19T23:59:59.000Z

    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.

  10. EEG alpha power and alpha power asymmetry in sleep and wakefulness

    E-Print Network [OSTI]

    Wisconsin at Madison, University of

    EEG alpha power and alpha power asymmetry in sleep and wakefulness RUTH M. BENCA,a,b WILLIAM H--Madison, USA Abstract Asymmetry of waking electroencephalography ~EEG! alpha power in frontal regions has been regarding alpha asymmetry during sleep. The present study was performed to compare alpha power and alpha

  11. 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)

    2013-12-09T23:59:59.000Z

    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.

  12. Tunable, superconducting, surface-emitting teraherz source

    DOE Patents [OSTI]

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

    2010-05-11T23:59:59.000Z

    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.

  13. 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)

    2009-10-27T23:59:59.000Z

    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.

  14. 7, 1271512750, 2007 Hydrogen isotope

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    imply that there must be a very strong concomitant isotopic enrichment in the radical channel (CH2O + hACPD 7, 12715­12750, 2007 Hydrogen isotope fractionation in the photolysis of formaldehyde T. S a Creative Commons License. Atmospheric Chemistry and Physics Discussions Hydrogen isotope fractionation

  15. Alpha Kappa Alpha Artificial Records, 1932-2000s

    E-Print Network [OSTI]

    2015-01-01T23:59:59.000Z

    THE OTHER SIDE OF THE RAINBOW ..... -; ALPHA KAPPA ALPHA SORORITY DELTA CHAPTER A REAL POT OF GOLD LIFt" EV'RY vOICE AND SING Li.6,t eV'!LY vo-i.c.e and ~-i.ng, T-i...t ea-uh and heaVe.l1 iU'lg, KUla w-i.,th tne. hMmolUe!.> 06 Llbeuy; Lei oun. !Le60...

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

    E-Print Network [OSTI]

    Gustavo R. Gonzalez-Martin

    2008-05-03T23:59:59.000Z

    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.

  17. Policy for Permitting Low-Emitting Sources  (West Virginia)

    Broader source: Energy.gov [DOE]

    While this policy alleviates some requirements on low-emitting emission sources, it does not change the policy of requiring applicants to submit reasonable information concerning all potential...

  18. alingap light emitting: Topics by E-print Network

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

    show a low threshold voltage for light emission of Potma, Eric Olaf 4 LIGHT EMITTING DIODE CHARACTERISTICS (SAMPLE LAB WRITEUP) Engineering Websites Summary: , 1997...

  19. active compounds emitted: Topics by E-print Network

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

    switching occurs even Rocca, Jorge J. 5 Transparent Active Matrix Organic Light-Emitting Diode Displays Driven by Chemistry Websites Summary: and portable electronics. In...

  20. airborne noise emitted: Topics by E-print Network

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

    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 Wetzel,...

  1. auger electron emitting: Topics by E-print Network

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

    diodes constructed from an electron online 30 September 2013 Keywords: Organic light-emitting diode Alternating current AC driving Color- and brightness-tunable organic...

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

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

    semipolar light-emitting diodes (LEDs) on low-defect bulk gallium nitride (GaN) substrates. Peak internal quantum efficiency (IQE) values of greater than 80% are...

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

    DOE Patents [OSTI]

    Thompson, Mark E.; Dapkus, P. Daniel

    2014-07-22T23:59:59.000Z

    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.

  4. Separation and Analysis of Actinides by Extraction Chromotography Coupled with Alpha Liquid Scintillation Spectrometry

    SciTech Connect (OSTI)

    Cadieux, J.R.; Reboul, S.H.

    1995-09-21T23:59:59.000Z

    This work describes the development and testing of a new method for the separation and analysis of most actinides of interest in environmental samples. It combines simplified extraction chromatography using highly selective absorption resins to partition the individual actinides with the measurement of their alpha activities by liquid scintillation spectrometry. The liquid scintillation counting technique pioneered by McDowell proved useful in determination of alpha emitting radionuclide in a wide variety of matrices. Alpha emitters are chemically extracted into an organic phase which also contains the scintillation cocktail. Oxygen is purged from the solution to improve the energy resolution of the measurement and the counting sample is sealed in a small glass tube for assay. The Photon-Electron Rejecting Alpha Liquid Scintillation (PERALS{trademark}) Spectrometer provides high counting efficiency, low background, pulse shape discrimination for photon/electron/{beta} particle rejection and moderate energy resolution in a compact package. Chemical extraction/liquid scintillation counting significantly reduces the extensive chemical purification and electroplating required for conventional alpha spectrometry with semiconductor detectors. PERALS{trademark} analyses have been used routinely for quickly surveying suspect samples and determining the source of unknown alpha activities.

  5. ISOTOPE METHODS IN HOMOGENEOUS CATALYSIS.

    SciTech Connect (OSTI)

    BULLOCK,R.M.; BENDER,B.R.

    2000-12-01T23:59:59.000Z

    The use of isotope labels has had a fundamentally important role in the determination of mechanisms of homogeneously catalyzed reactions. Mechanistic data is valuable since it can assist in the design and rational improvement of homogeneous catalysts. There are several ways to use isotopes in mechanistic chemistry. Isotopes can be introduced into controlled experiments and followed where they go or don't go; in this way, Libby, Calvin, Taube and others used isotopes to elucidate mechanistic pathways for very different, yet important chemistries. Another important isotope method is the study of kinetic isotope effects (KIEs) and equilibrium isotope effect (EIEs). Here the mere observation of where a label winds up is no longer enough - what matters is how much slower (or faster) a labeled molecule reacts than the unlabeled material. The most careti studies essentially involve the measurement of isotope fractionation between a reference ground state and the transition state. Thus kinetic isotope effects provide unique data unavailable from other methods, since information about the transition state of a reaction is obtained. Because getting an experimental glimpse of transition states is really tantamount to understanding catalysis, kinetic isotope effects are very powerful.

  6. 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)

    1995-01-01T23:59:59.000Z

    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.

  7. Laser isotope separation of erbium and other isotopes

    DOE Patents [OSTI]

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

    1995-08-22T23:59:59.000Z

    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.

  8. Workshop on Precision Measurements of $\\alpha_s$

    SciTech Connect (OSTI)

    Bethke, Siegfried; /Munich, Max Planck Inst.; Hoang, Andre H.; /Vienna U.; Kluth, Stefan; /Munich, Max Planck Inst.; Schieck, Jochen; /Munich U.; Stewart, Iain W.; Aoki, S.; Beneke, M.; Bethke, S.; Blumlein, J.; Brambilla, N.; Brodsky, S.; /MIT, LNS

    2011-10-01T23:59:59.000Z

    These are the proceedings of the Workshop on Precision Measurements of {alpha}{sub s} held at the Max-Planck-Institute for Physics, Munich, February 9-11, 2011. The workshop explored in depth the determination of {alpha}{sub s}(m{sub Z}) in the {ovr MS} scheme from the key categories where high precision measurements are currently being made, including DIS and global PDF fits, {tau}-decays, electro-weak 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.

  9. Water isotopes and the general circulation

    E-Print Network [OSTI]

    Noone, David

    is depleted. #12;Distillation: vapor and condensate Isotopic fractionation -35 -30 -25 -20 -15 -10 -5 0 5 0 0 of idealized isotopic fractionation Expression of isotopic fractionation in nature Attributing signals" 18 = (R/Rstandard-1)x1000 R = moles of H2 18O/moles of H2 16O #12;Isotopic fractionation Isotopic

  10. 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

    2002-07-31T23:59:59.000Z

    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.

  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. Effects of emitted electron temperature on the plasma sheath

    SciTech Connect (OSTI)

    Sheehan, J. P., E-mail: sheehanj@umich.edu [Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States); Kaganovich, I. D.; Wang, H.; Raitses, Y. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Sydorenko, D. [Physics Department, University of Alberta, Edmonton, Alberta T6G 2E9 (Canada); Hershkowitz, N. [Department of Engineering Physics, University of Wisconsin–Madison, Madison, Wisconsin 53706 (United States)

    2014-06-15T23:59:59.000Z

    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.

  13. 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

    2005-05-27T23:59:59.000Z

    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.

  14. RAPID FUSION METHOD FOR DETERMINATION OF PLUTONIUM ISOTOPES IN LARGE RICE SAMPLES

    SciTech Connect (OSTI)

    Maxwell, S.

    2013-03-01T23:59:59.000Z

    A new rapid fusion method for the determination of plutonium in large rice samples has been developed at the Savannah River National Laboratory (Aiken, SC, USA) that can be used to determine very low levels of plutonium isotopes in rice. The recent accident at Fukushima Nuclear Power Plant in March, 2011 reinforces the need to have rapid, reliable radiochemical analyses for radionuclides in environmental and food samples. Public concern regarding foods, particularly foods such as rice in Japan, highlights the need for analytical techniques that will allow very large sample aliquots of rice to be used for analysis so that very low levels of plutonium isotopes may be detected. The new method to determine plutonium isotopes in large rice samples utilizes a furnace ashing step, a rapid sodium hydroxide fusion method, a lanthanum fluoride matrix removal step, and a column separation process with TEVA Resin? cartridges. The method can be applied to rice sample aliquots as large as 5 kg. Plutonium isotopes can be determined using alpha spectrometry or inductively-coupled plasma mass spectrometry (ICP-MS). The method showed high chemical recoveries and effective removal of interferences. The rapid fusion technique is a rugged sample digestion method that ensures that any refractory plutonium particles are effectively digested. The MDA for a 5 kg rice sample using alpha spectrometry is 7E-5 mBq g{sup -1}. The method can easily be adapted for use by ICP-MS to allow detection of plutonium isotopic ratios.

  15. 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.

    1985-03-26T23:59:59.000Z

    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.

  16. 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)

    1996-01-01T23:59:59.000Z

    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).

  17. Efficient semiconductor light-emitting device and method

    DOE Patents [OSTI]

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

    1996-02-20T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    V. Yu. Denisov; H. Ikezoe

    2005-10-27T23:59:59.000Z

    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.

  19. Novel Isotope Effects and Organic Reaction Mechanisms

    E-Print Network [OSTI]

    Kelly, Kelmara K.

    2010-07-14T23:59:59.000Z

    to account for the observed isotope effects. In the dimerization of cyclopentadiene, novel "dynamic" isotope effects are observed on the 13C distribution in the product, and a method for the prediction of these isotope effects is developed here...

  20. The Giant Monopole Resonance in the Sn Isotopes: Why is Tin so "Fluffy"?

    E-Print Network [OSTI]

    U. Garg

    2006-08-03T23:59:59.000Z

    The isoscalar giant monopole resonance (GMR) has been investigated in a series of Sn isotopes (A=112--124) using inelstic scattering of 400-MeV alpha particles at extremely forward angles (including 0deg). The primary aim of the investigation has been to explore the role of the "symmetry-energy" term in the expression for nuclear incompressibility. It is found that the energies of the GMR in the Sn isotopes are significantly lower than those expected from the nuclear incompressibility previously extracted from the available data on the compressional-mode giant resonances.

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

    E-Print Network [OSTI]

    Kwok, Hoi S.

    , Kowloon, Hong Kong, China ABSTRACT For top emitting Organic Light-Emitting Diodes (OLED), the study of top layer is very important aiming to acquire good device performance. In this report, Pt as anode for Cu coated on glass as anode, copper (II) phthalocyanine (CuPc) as organic buffer layer, N,N'- diphenyl

  2. 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

  3. A Damped Ly-alpha Absorption-line System in an Apparent Void at Redshift 2.38

    E-Print Network [OSTI]

    L. E. H. Godfrey; P. J. Francis

    2005-06-22T23:59:59.000Z

    We study the contents of an apparent void in the distribution of Ly-alpha emitting galaxies at redshift 2.38. We show that this void is not empty, but contains a damped Ly-alpha absorption-line system, seen in absorption against background QSO 2138-4427. Imaging does not reveal any galaxy associated with this absorption-line system, but it contains metals (Fe/H ~ -1.3), and its large velocity range (~ 180 km/s) implies a significant mass.

  4. Four-nucleon alpha-type correlations and proton-neutron pairing away of N=Z line

    E-Print Network [OSTI]

    N. Sandulescu; D. Negrea; C. W. Johnson

    2012-09-15T23:59:59.000Z

    We study the competition between alpha-type and conventional pair condensation in the ground state of nuclei with neutrons and protons interacting via a charge-independent pairing interaction. The ground state is described by a product of two condensates, one of alpha-like quartets and the other one of pairs in excess relative to the isotope with N=Z. It is shown that this ansatz for the ground state gives very accurate pairing correlation energies for nuclei with the valence nucleons above the closed cores 16O, 40Ca and 100Sn. These results indicate that alpha-type correlations are important not only for the self-conjugate nuclei but also for nuclei away of N=Z line. In the latter case alpha-like quartets coexist with the collective Cooper pairs formed by the nucleons in excess.

  5. Four-nucleon alpha-type correlations and proton-neutron pairing away of N=Z line

    E-Print Network [OSTI]

    Sandulescu, N; Johnson, C W

    2012-01-01T23:59:59.000Z

    We study the competition between alpha-type and conventional pair condensation in the ground state of nuclei with neutrons and protons interacting via a charge-independent pairing interaction. The ground state is described by a product of two condensates, one of alpha-like quartets and the other one of pairs in excess relative to the isotope with N=Z. It is shown that this ansatz for the ground state gives very accurate pairing correlation energies for nuclei with the valence nucleons above the closed cores 16O, 40Ca and 100Sn. These results indicate that alpha-type correlations are important not only for the self-conjugate nuclei but also for nuclei away of N=Z line. In the latter case alpha-like quartets coexist with the collective Cooper pairs formed by the nucleons in excess.

  6. Chromatographic hydrogen isotope separation

    DOE Patents [OSTI]

    Aldridge, Frederick T. (Livermore, CA)

    1981-01-01T23:59:59.000Z

    Intermetallic compounds with the CaCu.sub.5 type of crystal structure, particularly LaNiCo.sub.4 and CaNi.sub.5, exhibit high separation factors and fast equilibrium times and therefore are useful for packing a chromatographic hydrogen isotope separation colum. The addition of an inert metal to dilute the hydride improves performance of the column. A large scale mutli-stage chromatographic separation process run as a secondary process off a hydrogen feedstream from an industrial plant which uses large volumes of hydrogen can produce large quantities of heavy water at an effective cost for use in heavy water reactors.

  7. ARM - Measurement - Isotope ratio

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow,ice particleSizegovMeasurementsIsotope ratio

  8. Nuclear Reaction Cross-Section Measurements via Characterization of Soft Radiation Emitting Products

    SciTech Connect (OSTI)

    Kettern, K.; Spahn, I.; Spellerberg, S.; Qaim, S.M.; Coenen, H.H. [Institut fuer Nuklearchemie, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany)

    2005-05-24T23:59:59.000Z

    Nuclear reaction cross-section measurements via the activation technique are generally made using high-resolution {gamma}-ray spectrometry. However, in cases where the radioactive product decays exclusively by EC (without emitting a {gamma}-ray) resort has to be made to the rather subtle technique of x-ray spectrometry. Similarly for characterisation of pure {beta}- emitters, gas-flow proportional or liquid-scintillation counting is applied. In both cases the use of radiochemical methods is most essential. We studied the natTi(p,xn)49V and 85Rb(p,4n)82Sr reactions via x-ray spectrometry. In each case a clean radiochemical separation was performed and a thin source was prepared. The radioactivity of 49V was determined using the soft 4.5-keV k{alpha} x-rays and that of 82Sr via the 13.4-keV k{alpha} x-rays. In another study, the reactions natTi(p,x)45Ca, 89Y(n,p)89Sr, and natPb(p,x)204Tl were investigated. All the products are pure {beta}- emitters and therefore clean radiochemical separations were mandatory. The radioactivity of each of the three products was determined via low-level anticoincidence {beta}- counting. Furthermore, in the case of 45Ca, liquid-scintillation counting was also used. The results obtained using different techniques are compared.

  9. The marine biogeochemistry of zinc isotopes

    E-Print Network [OSTI]

    John, Seth G

    2007-01-01T23:59:59.000Z

    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, ...

  10. Stable Isotope Fractionations in Biogeochemical Reactive Transport

    E-Print Network [OSTI]

    Druhan, Jennifer Lea

    2012-01-01T23:59:59.000Z

    characteristic of stable isotope enrichment. The values of !isotope ratios of sulfur in these sulfate samples demonstrated a clear enrichmentisotope ( 34 S) (Canfield, 2001). The characteristic enrichment

  11. Strategic Isotope Production | ornl.gov

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

    Strategic Isotope Production SHARE Strategic Isotope Production Typical capsules used in the transport of 252Cf source material inside heavily shielded shipping casks. ORNL's...

  12. Isotopic Trends in Production of Superheavies

    SciTech Connect (OSTI)

    Antonenko, N.V. [Institut fuer Theoretische Physik der Justus-Liebig-Universitaet, D-35392 Giessen (Germany); Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Adamian, G.G.; Zubov, A.S. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Scheid, W. [Institut fuer Theoretische Physik der Justus-Liebig-Universitaet, D-35392 Giessen (Germany)

    2005-11-21T23:59:59.000Z

    The isotopic trends are discussed for cold and hot fusion reactions leading to superheavies. The possibilities of production of new isotopes in incomplete fusion reactions are treated.

  13. 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

    2010-05-13T23:59:59.000Z

    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.

  14. 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

  15. Method of separating boron isotopes

    DOE Patents [OSTI]

    Jensen, Reed J. (Los Alamos, NM); Thorne, James M. (Provo, UT); Cluff, Coran L. (Provo, UT); Hayes, John K. (Salt Lake City, UT)

    1984-01-01T23:59:59.000Z

    A method of boron isotope enrichment involving the isotope preferential photolysis of (2-chloroethenyl)dichloroborane as the feed material. The photolysis can readily be achieved with CO.sub.2 laser radiation and using fluences significantly below those required to dissociate BCl.sub.3.

  16. Method of separating boron isotopes

    DOE Patents [OSTI]

    Jensen, R.J.; Thorne, J.M.; Cluff, C.L.

    1981-01-23T23:59:59.000Z

    A method of boron isotope enrichment involving the isotope preferential photolysis of (2-chloroethenyl)-dichloroborane as the feed material. The photolysis can readily by achieved with CO/sub 2/ laser radiation and using fluences significantly below those required to dissociate BCl/sub 3/.

  17. 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

  18. Pulse-shape discrimination of scintillation from alpha and beta particles with liquid scintillator and Geiger-mode multipixel avalanche diodes

    E-Print Network [OSTI]

    Kreslo, I; Delaquis, S; Ereditato, A; Janos, S; Messina, M; Moser, U; Rossi, B; Zeller, M

    2011-01-01T23:59:59.000Z

    A successfull application of Geiger-mode multipixel avalanche diodes (GMAPDs) for pulse-shape discrimination in alpha-beta spectrometry using organic liquid scintillator is described in this paper. Efficient discrimination of alpha and beta components in the emission of radioactive isotopes is achieved for alpha energies above 0.3 MeV. The ultra-compact design of the scintillating detector helps to efficiently suppress cosmic-ray and ambient radiation background. This approach allows construction of hand-held robust devices for monitoring of radioactive contamination in various environmental conditions.

  19. Pulse-shape discrimination of scintillation from alpha and beta particles with liquid scintillator and Geiger-mode multipixel avalanche diodes

    E-Print Network [OSTI]

    I. Kreslo; I. Badhrees; S. Delaquis; A. Ereditato; S. Janos; M. Messina; U. Moser; B. Rossi; M. Zeller

    2011-06-23T23:59:59.000Z

    A successfull application of Geiger-mode multipixel avalanche diodes (GMAPDs) for pulse-shape discrimination in alpha-beta spectrometry using organic liquid scintillator is described in this paper. Efficient discrimination of alpha and beta components in the emission of radioactive isotopes is achieved for alpha energies above 0.3 MeV. The ultra-compact design of the scintillating detector helps to efficiently suppress cosmic-ray and ambient radiation background. This approach allows construction of hand-held robust devices for monitoring of radioactive contamination in various environmental conditions.

  20. 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

    2015-01-01T23:59:59.000Z

    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...

  1. Isotope separation by laser means

    DOE Patents [OSTI]

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

    1982-06-15T23:59:59.000Z

    A process 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.

  2. 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

    2015-01-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Kong, Jieying

    2012-01-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Choi, Jae Ik

    2014-01-01T23:59:59.000Z

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

  5. White light emitting diode as liquid crystal display backlight

    E-Print Network [OSTI]

    Soon, Chian Myau

    2007-01-01T23:59:59.000Z

    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 ...

  6. Metal-halide perovskites for photovoltaic and light-emitting...

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

    Metal-halide perovskites for photovoltaic and light-emitting devices September 15, 2015 at 4:30 pm36-428 Sam Stranks Massachusetts Institute of Technology peopleStranks...

  7. 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 ...

  8. Organic light emitting device structure for obtaining chromaticity stability

    DOE Patents [OSTI]

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

    2007-05-01T23:59:59.000Z

    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. Interference of Cooper Pairs Emitted from Independent Superconductors

    E-Print Network [OSTI]

    Mauro Iazzi; Kazuya Yuasa

    2010-05-16T23:59:59.000Z

    We discuss the interference in the two-particle distribution of the electrons emitted from two independent superconductors. It is clarified that, while the interference appearing in the antibunching correlation is due to the Hanbury Brown and Twiss effect, that in the positive correlation due to superconductivity is intrinsically different and is nothing but the first-order interference of Cooper pairs emitted from different sources. This is the equivalent of the interference of two independent Bose-Einstein condensates.

  10. SOURCES-3A: A code for calculating ({alpha}, n), spontaneous fission, and delayed neutron sources and spectra

    SciTech Connect (OSTI)

    Perry, R.T.; Wilson, W.B.; Charlton, W.S.

    1998-04-01T23:59:59.000Z

    In many systems, it is imperative to have accurate knowledge of all significant sources of neutrons due to the decay of radionuclides. These sources can include neutrons resulting from the spontaneous fission of actinides, the interaction of actinide decay {alpha}-particles in ({alpha},n) reactions with low- or medium-Z nuclides, and/or delayed neutrons from the fission products of actinides. Numerous systems exist in which these neutron sources could be important. These include, but are not limited to, clean and spent nuclear fuel (UO{sub 2}, ThO{sub 2}, MOX, etc.), enrichment plant operations (UF{sub 6}, PuF{sub 4}, etc.), waste tank studies, waste products in borosilicate glass or glass-ceramic mixtures, and weapons-grade plutonium in storage containers. SOURCES-3A 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 in homogeneous media (i.e., a mixture of {alpha}-emitting source material and low-Z target material) and in interface problems (i.e., a slab of {alpha}-emitting source material in contact with a slab of low-Z target material). The code is also capable of calculating the neutron production rates due to ({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.

  11. Apparatus and process for separating hydrogen isotopes

    DOE Patents [OSTI]

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

    2013-06-25T23:59:59.000Z

    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.

  12. Method for laser induced isotope enrichment

    DOE Patents [OSTI]

    Pronko, Peter P.; Vanrompay, Paul A.; Zhang, Zhiyu

    2004-09-07T23:59:59.000Z

    Methods for separating isotopes or chemical species of an element and causing enrichment of a desired isotope or chemical species of an element utilizing laser ablation plasmas to modify or fabricate a material containing such isotopes or chemical species are provided. This invention may be used for a wide variety of materials which contain elements having different isotopes or chemical species.

  13. 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

  14. Low-Cost Light-Emitting Diode Luminaire for General Illumination...

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

    Cost Light-Emitting Diode Luminaire for General Illumination Low-Cost Light-Emitting Diode Luminaire for General Illumination Presenter: Paul Fini, CREE Santa Barbara Technology...

  15. Compelling Research Opportunities using Isotopes

    SciTech Connect (OSTI)

    None

    2009-04-23T23:59:59.000Z

    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.

  16. Electrochemical Isotope Effect and Lithium Isotope Separation Jay R. Black,

    E-Print Network [OSTI]

    Mcdonough, William F.

    results showing a large lithium isotope separation due to electrodeposition. The fractionation is tunable lithium were plated from solutions of 1 M LiClO4 in propylene carbonate (PC) on planar nickel electrodes

  17. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProducts (VAP) VAP7-0973ManagedStrategic|AljazeeraO S o'ware a nd D ata Alok

  18. First observation of /sup 162/Hf decay completion of an alpha -decay chain

    E-Print Network [OSTI]

    Schrewe, U J; Hagberg, E; Hardy, J C; Koslowsky, V T; Schmeing, H; Sharma, K S

    1981-01-01T23:59:59.000Z

    The new isotope /sup 162/Hf (T/sub 1/2/=(37.6+or-0.8)s) is produced in a /sup 142/Nd (/sup 24/Mg,4n) reaction. The activities produced in this reaction are transported to a measuring station by use of a He- jet system. Decay properties are observed with alpha -, gamma -, and gamma - gamma -spectroscopy. The Z-assignment of the new isotope is based on a cross bombardment on /sup 141/Pr target and on the results of a gamma -X-ray coincidence measurement. The mass assignment is deduced from the excitation function measurements. From the measured alpha -decay energy E/sub alpha /=4308 (10) keV new mass values are derived for /sup 162/Hf, /sup 166/W, /sup 170/Os, /sup 174/Pt, and /sup 178/Hg. These new mass values make it possible to establish systematics of two-proton and one-proton binding energies far from stability. (20 refs).

  19. Novel hybrid isotope separation scheme and apparatus

    DOE Patents [OSTI]

    Maya, Jakob (Brookline, MA)

    1991-01-01T23:59:59.000Z

    A method of 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.

  20. Novel hybrid isotope separation scheme and apparatus

    DOE Patents [OSTI]

    Maya, J.

    1991-06-18T23:59:59.000Z

    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.

  1. Selective photoionisation of lutetium isotopes

    SciTech Connect (OSTI)

    D'yachkov, Aleksei B; Kovalevich, S K; Labozin, Valerii P; Mironov, Sergei M; Panchenko, Vladislav Ya; Firsov, Valerii A; Tsvetkov, G O; Shatalova, G G [National Research Centre 'Kurchatov Institute', Moscow (Russian Federation)

    2012-10-31T23:59:59.000Z

    A three-stage laser photoionisation scheme intended for enriching the {sup 176}Lu isotope from natural lutetium was considered. An investigation was made of the hyperfine structure of the second excited state 5d6s7s {yields} {sup 4}D{sub 3/2} with an energy of 37194 cm{sup -1} and the autoionisation state with an energy of 53375 cm{sup -1} of the {sup 176}Lu and {sup 175}Lu isotopes. The total electron momentum of the autoionisation level and the constant A of hyperfine magnetic interaction were determined. Due to a small value of the isotopic shift between {sup 176}Lu and {sup 175}Lu, appreciable selectivity of their separation may be achieved with individual hyperfine structure components. The first tentative enrichment of the 176Lu isotope was performed to a concentration of 60 % - 70 %. (laser applications and other topics in quantum electronics)

  2. 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)

    2010-07-15T23:59:59.000Z

    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.

  3. 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...

  4. ALPHN: A computer program for calculating ([alpha], n) neutron production in canisters of high-level waste

    SciTech Connect (OSTI)

    Salmon, R.; Hermann, O.W.

    1992-10-01T23:59:59.000Z

    The rate of neutron production from ([alpha], n) reactions in canisters of immobilized high-level waste containing borosilicate glass or glass-ceramic compositions is significant and must be considered when estimating neutron shielding requirements. The personal computer program ALPHA calculates the ([alpha], n) neutron production rate of a canister of vitrified high-level waste. The user supplies the chemical composition of the glass or glass-ceramic and the curies of the alpha-emitting actinides present. The output of the program gives the ([alpha], n) neutron production of each actinide in neutrons per second and the total for the canister. The ([alpha], n) neutron production rates are source terms only; that is, they are production rates within the glass and do not take into account the shielding effect of the glass. For a given glass composition, the user can calculate up to eight cases simultaneously; these cases are based on the same glass composition but contain different quantities of actinides per canister. In a typical application, these cases might represent the same canister of vitrified high-level waste at eight different decay times. Run time for a typical problem containing 20 chemical species, 24 actinides, and 8 decay times was 35 s on an IBM AT personal computer. Results of an example based on an expected canister composition at the Defense Waste Processing Facility are shown.

  5. ALPHN: A computer program for calculating ({alpha}, n) neutron production in canisters of high-level waste

    SciTech Connect (OSTI)

    Salmon, R.; Hermann, O.W.

    1992-10-01T23:59:59.000Z

    The rate of neutron production from ({alpha}, n) reactions in canisters of immobilized high-level waste containing borosilicate glass or glass-ceramic compositions is significant and must be considered when estimating neutron shielding requirements. The personal computer program ALPHA calculates the ({alpha}, n) neutron production rate of a canister of vitrified high-level waste. The user supplies the chemical composition of the glass or glass-ceramic and the curies of the alpha-emitting actinides present. The output of the program gives the ({alpha}, n) neutron production of each actinide in neutrons per second and the total for the canister. The ({alpha}, n) neutron production rates are source terms only; that is, they are production rates within the glass and do not take into account the shielding effect of the glass. For a given glass composition, the user can calculate up to eight cases simultaneously; these cases are based on the same glass composition but contain different quantities of actinides per canister. In a typical application, these cases might represent the same canister of vitrified high-level waste at eight different decay times. Run time for a typical problem containing 20 chemical species, 24 actinides, and 8 decay times was 35 s on an IBM AT personal computer. Results of an example based on an expected canister composition at the Defense Waste Processing Facility are shown.

  6. Production of gallium-66, a positron emitting nuclide for radioimmunotherapy

    SciTech Connect (OSTI)

    Mirzadeh, S. (Oak Ridge National Lab., TN (United States)); Chu, Y.Y. (Brookhaven National Lab., Upton, NY (United States))

    1991-01-01T23:59:59.000Z

    Excitation functions for production of {sup 66}Ga via {alpha}-induced nuclear reactions on enriched {sup 66}Zn and {sup 64}Zn have been measured with E{sub {alpha}}{le}27.3 MeV and E{sub {alpha}}{le}43.7 MeV employing the stack-thin target technique. In addition, the induced activity of {sup 67} Ga in the same sets of targets allowed an evaluation of the excitation functions of the corresponding nuclear reactions.

  7. Production of gallium-66, positron emitting nuclide for radioimmumotherapy

    SciTech Connect (OSTI)

    Mirzadeh, S. (Oak Ridge National Lab., TN (USA)); Chu, Yung Yee (Brookhaven National Lab., Upton, NY (USA))

    1991-01-01T23:59:59.000Z

    Excitation functions for production of {sup 66}Ga via {alpha}-induced nuclear reactions on enriched {sup 66}Zn have been measured with E{sub {alpha}}{le}27.3 MeV and E{sub {alpha}}{le}43.7 MeV employing the stack-thin target technique. In addition, the induced activity of {sup 67}Ga in the same sets of targets allowed an evaluation of the excitation functions of the corresponding nuclear reactions. 17 refs., 2 figs., 2 tabs.

  8. Production of gallium-66, a positron emitting nuclide for radioimmunotherapy

    SciTech Connect (OSTI)

    Mirzadeh, S. [Oak Ridge National Lab., TN (United States); Chu, Y.Y. [Brookhaven National Lab., Upton, NY (United States)

    1991-12-31T23:59:59.000Z

    Excitation functions for production of {sup 66}Ga via {alpha}-induced nuclear reactions on enriched {sup 66}Zn and {sup 64}Zn have been measured with E{sub {alpha}}{le}27.3 MeV and E{sub {alpha}}{le}43.7 MeV employing the stack-thin target technique. In addition, the induced activity of {sup 67} Ga in the same sets of targets allowed an evaluation of the excitation functions of the corresponding nuclear reactions.

  9. High gas flow alpha detector

    DOE Patents [OSTI]

    Bolton, R.D.; Bounds, J.A.; Rawool-Sullivan, M.W.

    1996-05-07T23:59:59.000Z

    An alpha detector for application in areas of high velocity gas flows, such as smokestacks and air vents. A plurality of spaced apart signal collectors are placed inside an enclosure, which would include smokestacks and air vents, in sufficient numbers to substantially span said enclosure so that gas ions generated within the gas flow are electrostatically captured by the signal collector means. Electrometer means and a voltage source are connected to the signal collectors to generate an electrical field between adjacent signal collectors, and to indicate a current produced through collection of the gas ions by the signal collectors. 4 figs.

  10. High gas flow alpha detector

    DOE Patents [OSTI]

    Bolton, Richard D. (Los Alamos, NM); Bounds, John A. (Los Alamos, NM); Rawool-Sullivan, Mohini W. (Los Alamos, NM)

    1996-01-01T23:59:59.000Z

    An alpha detector for application in areas of high velocity gas flows, such as smokestacks and air vents. A plurality of spaced apart signal collectors are placed inside an enclosure, which would include smokestacks and air vents, in sufficient numbers to substantially span said enclosure so that gas ions generated within the gas flow are electrostatically captured by the signal collector means. Electrometer means and a voltage source are connected to the signal collectors to generate an electrical field between adjacent signal collectors, and to indicate a current produced through collection of the gas ions by the signal collectors.

  11. Alpha Technologies | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTriWildcat Place: Wayne,Energy Information Jump to:Alpha Energy

  12. 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]

    Kwok, Hoi S.

    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

  13. Isotope specific resolution recovery image reconstruction in high resolution PET imaging

    SciTech Connect (OSTI)

    Kotasidis, Fotis A. [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva, Switzerland and Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, M20 3LJ, Manchester (United Kingdom)] [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva, Switzerland and Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, M20 3LJ, Manchester (United Kingdom); Angelis, Georgios I. [Faculty of Health Sciences, Brain and Mind Research Institute, University of Sydney, NSW 2006, Sydney (Australia)] [Faculty of Health Sciences, Brain and Mind Research Institute, University of Sydney, NSW 2006, Sydney (Australia); Anton-Rodriguez, Jose; Matthews, Julian C. [Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, Manchester M20 3LJ (United Kingdom)] [Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, Manchester M20 3LJ (United Kingdom); Reader, Andrew J. [Montreal Neurological Institute, McGill University, Montreal QC H3A 2B4, Canada and Department of Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas’ Hospital, London SE1 7EH (United Kingdom)] [Montreal Neurological Institute, McGill University, Montreal QC H3A 2B4, Canada and Department of Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas’ Hospital, London SE1 7EH (United Kingdom); Zaidi, Habib [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva (Switzerland) [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva (Switzerland); Geneva Neuroscience Centre, Geneva University, CH-1205 Geneva (Switzerland); Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, PO Box 30 001, Groningen 9700 RB (Netherlands)

    2014-05-15T23:59:59.000Z

    Purpose: Measuring and incorporating a scanner-specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However, due to the short half-life of clinically used isotopes, other long-lived isotopes not used in clinical practice are used to perform the PSF measurements. As such, non-optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction, usually underestimating the true PSF owing to the difference in positron range. In high resolution brain and preclinical imaging, this effect is of particular importance since the PSFs become more positron range limited and isotope-specific PSFs can help maximize the performance benefit from using resolution recovery image reconstruction algorithms. Methods: In this work, the authors used a printing technique to simultaneously measure multiple point sources on the High Resolution Research Tomograph (HRRT), and the authors demonstrated the feasibility of deriving isotope-dependent system matrices from fluorine-18 and carbon-11 point sources. Furthermore, the authors evaluated the impact of incorporating them within RM image reconstruction, using carbon-11 phantom and clinical datasets on the HRRT. Results: The results obtained using these two isotopes illustrate that even small differences in positron range can result in different PSF maps, leading to further improvements in contrast recovery when used in image reconstruction. The difference is more pronounced in the centre of the field-of-view where the full width at half maximum (FWHM) from the positron range has a larger contribution to the overall FWHM compared to the edge where the parallax error dominates the overall FWHM. Conclusions: Based on the proposed methodology, measured isotope-specific and spatially variant PSFs can be reliably derived and used for improved spatial resolution and variance performance in resolution recovery image reconstruction. The benefits are expected to be more substantial for more energetic positron emitting isotopes such as Oxygen-15 and Rubidium-82.

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

    SciTech Connect (OSTI)

    Huang, C.Y. [University of Sydney, Camperdown, NSW (Australia); Guatelli, S [University of Wollongong, Wollongong, NSW (Australia); Oborn, B [Illawarra Cancer Care Centre, Wollongong, NSW (Australia); Allen, B [University of Western Sydney, Liverpool, NSW (Australia)

    2014-06-01T23:59:59.000Z

    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.

  15. Local Varying-Alpha Theories

    E-Print Network [OSTI]

    John D. Barrow; Joao Magueijo

    2015-01-30T23:59:59.000Z

    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.

  16. Beta/alpha continuous air monitor

    DOE Patents [OSTI]

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

    1989-01-01T23:59:59.000Z

    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.

  17. Beta/alpha continuous air monitor

    DOE Patents [OSTI]

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

    1988-06-27T23:59:59.000Z

    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.

  18. Prospects for alpha particle studies on TFTR

    SciTech Connect (OSTI)

    Zweben, S.J.

    1987-05-01T23:59:59.000Z

    TFTR is expected to produce approximately 5 MW of alpha heating during the D/T Q approx. = 1 phase of operation in 1990. At that point the collective confinement properties and the heating effects of alpha particles become accessible for study for the first time. This paper outlines the potential performance of TFTR with respect to alpha particle production, the diagnostics which will be available for alpha particle measurements, and the physics issues which can be studied both before and during D/T operation.

  19. 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 

  20. 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

    2004-11-30T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

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

    2005-11-29T23:59:59.000Z

    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.

  2. Close-packed array of light emitting devices

    SciTech Connect (OSTI)

    Ivanov, Ilia N.; Simpson, John T.

    2013-04-09T23:59:59.000Z

    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.

  3. Oxycarbonitride phosphors and light emitting devices using the same

    DOE Patents [OSTI]

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

    2014-07-08T23:59:59.000Z

    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.

  4. Oxycarbonitride phosphors and light emitting devices using the same

    DOE Patents [OSTI]

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

    2013-10-08T23:59:59.000Z

    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.

  5. 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

    2010-01-01T23:59:59.000Z

    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.

  6. On spontaneous fission and alpha-decay half-lives of atomic nuclei

    E-Print Network [OSTI]

    K. Pomorski; M. Warda; A. Zdeb

    2015-01-16T23:59:59.000Z

    It is shown, that the Gamow-like model with only one adjustable parameter - radius constant is able to reproduce well the alpha-decay half-lives for all even-even nuclei with the proton number larger than 50. The systematics for odd-A and odd-odd isotopes can be also well described when ones introduces an additional hindrance factor. Similar model based on the W. J. Swiatecki idea from 1955 is developed to reproduce the spontaneous fission half-lives of transactinide nuclei. The achieved accuracy of reproduction of the data is better than that obtained in more advanced theories.

  7. Nickel isotopes in stellar matter

    E-Print Network [OSTI]

    Jameel-Un Nabi

    2014-08-19T23:59:59.000Z

    Isotopes of nickel play a key role during the silicon burning phase up to the presupernova phase of massive stars. Electron capture rates on these nickel isotopes are also important during the phase of core contraction. I present here the microscopic calculation of ground and excited states Gamow-Teller (GT) strength distributions for key nickel isotopes. The calculation is performed within the frame-work of pn-QRPA model. A judicious choice of model parameters, specially of the Gamow-Teller strength parameters and the deformation parameter, resulted in a much improved calculation of GT strength functions. The excited state GT distributions are much different from the corresponding ground-state distributions resulting in a failure of the Brink's hypothesis. The electron capture and positron decay rates on nickel isotopes are also calculated within the framework of pn-QRPA model relevant to the presupernova evolution of massive stars. The electron capture rates on odd-A isotopes of nickel are shown to have dominant contributions from parent excited states during as early as silicon burning phases. Comparison is being made with the large scale shell model calculation. During the silicon burning phases of massive stars the electron capture rates on $^{57,59}$Ni are around an order of magnitude bigger than shell model rates and can bear consequences for core-collapse simulators.

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

    E-Print Network [OSTI]

    Thomas Kluge

    2006-10-13T23:59:59.000Z

    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.

  9. Mechanistic studies using kinetic isotope effects

    E-Print Network [OSTI]

    Schulmeier, Brian E.

    1999-01-01T23:59:59.000Z

    Understanding reaction mechanisms is an important aspect of chemistry. A now convenient way to study reaction mechanisms is kinetic isotope effects at natural abundance. This technique circumvents the cumbersome methods of traditional isotope effect...

  10. 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.

  11. 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 V

  12. 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.

    2014-08-03T23:59:59.000Z

    a Keithley 2400 Source Measure Unit (SMU). Photon flux was measured simultaneously using a calibrated silicon photodiode centered over the light-emitting pixel. Radiance in W sr-1 m-2 and luminance in cd m-2 10 were calculated based...

  13. 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

  14. 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

  15. Isotope Development & Production | Nuclear Science | ORNL

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

    Medical Radioisotope Radiochemical Separation & Processing Strategic Isotope Production Super Heavy Element Discovery Nuclear Security Science & Technology Nuclear Systems...

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

    SciTech Connect (OSTI)

    Kwang-Ohk Cheon

    2003-08-05T23:59:59.000Z

    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.

  17. Ultimate Isotope Precision for Carbonates Thermo Scientific

    E-Print Network [OSTI]

    Lachniet, Matthew S.

    Ultimate Isotope Precision for Carbonates Thermo Scientific KIEL IV Carbonate Device Part of Thermo integration cycle Ultimate Isotope Precision for Carbonates The Thermo Scientific KIEL IV Carbonate DeviceV Thermo Scientific MAT 253 or the 3-kV DELTA V isotope ratio mass spectrometer meets the requirements

  18. Isotope Cancer Treatment Research at LANL

    ScienceCinema (OSTI)

    Weidner, John; Nortier, Meiring

    2014-06-02T23:59:59.000Z

    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.

  19. alpha inducido por: Topics by E-print Network

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

    present review provides an update on alphas measurements from the past year. W. J. Stirling 1997-09-23 5 ALPHA OMEGA ALPHA National Honor Medical Society Biology and Medicine...

  20. alpha pparalpha protects: Topics by E-print Network

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

    present review provides an update on alphas measurements from the past year. W. J. Stirling 1997-09-23 6 ALPHA OMEGA ALPHA National Honor Medical Society Biology and Medicine...

  1. alpha autoradiography: Topics by E-print Network

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

    present review provides an update on alphas measurements from the past year. W. J. Stirling 1997-09-23 6 ALPHA OMEGA ALPHA National Honor Medical Society Biology and Medicine...

  2. alpha device: Topics by E-print Network

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

    present review provides an update on alphas measurements from the past year. W. J. Stirling 1997-09-23 3 ALPHA OMEGA ALPHA National Honor Medical Society Biology and Medicine...

  3. alpha dosimetry: Topics by E-print Network

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

    present review provides an update on alphas measurements from the past year. W. J. Stirling 1997-09-23 3 ALPHA OMEGA ALPHA National Honor Medical Society Biology and Medicine...

  4. alpha kaudu transleeritavatest: Topics by E-print Network

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

    present review provides an update on alphas measurements from the past year. W. J. Stirling 1997-09-23 3 ALPHA OMEGA ALPHA National Honor Medical Society Biology and Medicine...

  5. alpha muzka ostajotsja: Topics by E-print Network

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

    present review provides an update on alphas measurements from the past year. W. J. Stirling 1997-09-23 3 ALPHA OMEGA ALPHA National Honor Medical Society Biology and Medicine...

  6. alpha particle physics: Topics by E-print Network

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

    towards an alpha product state. It is shown that single alpha particle orbits in condensates of different nuclei are almost the same. It is thus argued that alpha particle...

  7. Cluster structures in Oxygen isotopes

    E-Print Network [OSTI]

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

    2007-06-01T23:59:59.000Z

    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.

  8. 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.

    2013-09-01T23:59:59.000Z

    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.

  9. The Multiphase Halo of NGC 891: WIYN H-alpha and BVI Imaging

    E-Print Network [OSTI]

    J. Christopher Howk; Blair D. Savage

    1999-10-14T23:59:59.000Z

    We present new, deep optical images (BVI+H-alpha) of the interstellar medium (ISM) far above the plane of NGC 891. These sub-arcsecond images give a direct visual view of two physically distinct ``phases'' of the thick interstellar disk of this galaxy. A dense phase of the thick disk ISM is observed in our BVI images as highly-structured dust-bearing clouds viewed against the stellar light of the galaxy. These structures are traceable to heights |z|=2 kpc from the midplane. Very few highly-structured dust features are present at |z|>2 kpc. The more prominent dust structures have gas masses in excess of 10^5 solar masses, each having visual extinctions well in excess of unity. A warm ionized phase of the high-z ISM is observed through its well-studied H-alpha emission. Our images of the well-studied diffuse ionized medium, to date the highest-resolution observations of this phase of the ISM in NGC 891, show it is relatively smoothly distributed with some filamentary structure superposed on this smooth background. There is little correspondence between the H-alpha emitting material and the absorbing dust structures. These two phases of the multiphase high-z ISM are physically distinct. The H-alpha emission is being heavily extincted in many places by the dense dust-bearing medium. Our H-alpha observations show evidence for several discrete H II regions at large distances from the midplane (to |z|=2 kpc). The presence of these H II regions in the thick disk of NGC 891 suggests that on-going star formation may be present in some of the dense, high-z clouds visible in our images. (Abstract Abridged)

  10. alpha energy measurements: Topics by E-print Network

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

    with ATLAS Jet Production Measurements. CERN Preprints Summary: An inclusive jet multiplicity ratio is sensitive to the strong coupling constant, alphaS and has reduced...

  11. alpha continuous air: Topics by E-print Network

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

    HEP - Experiment (arXiv) Summary: We present a review of measurements of alphaS. The individual measurements are discussed and intermediate averages for classes of related...

  12. CRAD, Quality Assurance - Oak Ridge National Laboratory TRU ALPHA...

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

    Quality Assurance - Oak Ridge National Laboratory TRU ALPHA LLWT Project CRAD, Quality Assurance - Oak Ridge National Laboratory TRU ALPHA LLWT Project November 2003 A section of...

  13. SUMOylation of ROR{alpha} potentiates transcriptional activation function

    SciTech Connect (OSTI)

    Hwang, Eun Ju [Department of Biological Sciences, Research Center for Women's Disease, Sookmyung Women's University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742 (Korea, Republic of); Lee, Ji Min [Department of Biological Sciences, Seoul National University, Seoul 151-742 (Korea, Republic of); Jeong, Jiyeong; Park, Joo Hyeon; Yang, Young; Lim, Jong-Seok [Department of Biological Sciences, Research Center for Women's Disease, Sookmyung Women's University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742 (Korea, Republic of); Kim, Jung Hwa [Department of Medical Sciences, Inha University, Incheon 402-751 (Korea, Republic of); Baek, Sung Hee [Department of Biological Sciences, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, Keun Il [Department of Biological Sciences, Research Center for Women's Disease, Sookmyung Women's University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742 (Korea, Republic of)], E-mail: kikim@sookmyung.ac.kr

    2009-01-16T23:59:59.000Z

    SUMOylation regulates a variety of cellular processes, including control of transcriptional activities of nuclear receptors. Here, we present SUMOylation of orphan nuclear receptor, ROR{alpha} by both SUMO-1 and SUMO-2. SUMOylation of ROR{alpha} occurred on the 240th lysine residue at the hinge region of human protein. PIAS family members, PIASx{alpha}, PIAS3, and PIASy, increased SUMOylation of ROR{alpha}, whereas SENP2 specifically removed SUMO from ROR{alpha}. SUMOylation-defective mutant form of ROR{alpha} exhibited decreased transcriptional activity on ROR{alpha}-responsive promoters indicating that SUMOylation may positively regulate transcriptional function of ROR{alpha}.

  14. alpha iib beta: Topics by E-print Network

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

    Yu. G. Zdesenko 2004-04-13 9 Alpha Backgrounds and Their Implications for Neutrinoless Double-Beta Decay Experiments Using HPGe Detectors Physics Websites Summary: Alpha...

  15. alpha trihydroxy-5 beta: Topics by E-print Network

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

    Yu. G. Zdesenko 2004-04-13 7 Alpha Backgrounds and Their Implications for Neutrinoless Double-Beta Decay Experiments Using HPGe Detectors Physics Websites Summary: Alpha...

  16. alpha implication des: Topics by E-print Network

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

    XI, Universit de 3 Alpha Backgrounds and Their Implications for Neutrinoless Double-Beta Decay Experiments Using HPGe Detectors Physics Websites Summary: Alpha...

  17. alpha 2-macroglobulin implications: Topics by E-print Network

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

    J Mol Obbard, Darren 6 Alpha Backgrounds and Their Implications for Neutrinoless Double-Beta Decay Experiments Using HPGe Detectors Physics Websites Summary: Alpha...

  18. alpha gross beta: Topics by E-print Network

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

    Yu. G. Zdesenko 2004-04-13 14 Alpha Backgrounds and Their Implications for Neutrinoless Double-Beta Decay Experiments Using HPGe Detectors Physics Websites Summary: Alpha...

  19. alpha beta forms: Topics by E-print Network

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

    R. Williamson 2005-04-04 14 Alpha Backgrounds and Their Implications for Neutrinoless Double-Beta Decay Experiments Using HPGe Detectors Physics Websites Summary: Alpha...

  20. alpha magnetic spectrometer: Topics by E-print Network

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

    23 24 25 Next Page Last Page Topic Index 1 Testing and Final Construction of the Superconducting Magnet for the Alpha Magnetic Spectrometer MIT - DSpace Summary: The Alpha...

  1. alpha-deuterium isotope effects: Topics by E-print Network

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

    by High-Field Ion Mobility ions, including isotopomers and isobars, using ion mobility spectrometry (IMS), specifically, the field) and ion mobility spectrometry (IMS).1,2...

  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. Luminescence and Squeezing of a Superconducting Light Emitting Diode

    E-Print Network [OSTI]

    Patrik Hlobil; Peter P. Orth

    2015-05-11T23:59:59.000Z

    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.

  4. Luminescence and Squeezing of a Superconducting Light Emitting Diode

    E-Print Network [OSTI]

    Hlobil, Patrik

    2015-01-01T23:59:59.000Z

    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.

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

    DOE Patents [OSTI]

    Omary, Mohammad A

    2013-11-12T23:59:59.000Z

    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").

  6. Luminescence and Squeezing of a Superconducting Light Emitting Diode

    E-Print Network [OSTI]

    Patrik Hlobil; Peter P. Orth

    2015-02-17T23:59:59.000Z

    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.

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

    DOE Patents [OSTI]

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

    2014-01-21T23:59:59.000Z

    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.

  8. Electrically injected visible vertical cavity surface emitting laser diodes

    DOE Patents [OSTI]

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

    1994-09-27T23:59:59.000Z

    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.

  9. Coherent flash of light emitted by a cold atomic cloud

    SciTech Connect (OSTI)

    Chalony, M. [Institut Non Lineaire de Nice, Universite de Nice Sophia-Antipolis, CNRS, F-06560 Valbonne (France); Pierrat, R. [Institut Langevin, ESPCI ParisTech, CNRS UMR 7587, 10 rue Vauquelin, F-75005 Paris (France); Delande, D. [Laboratoire Kastler Brossel, UPMC-Paris 6, ENS, CNRS, 4 Place Jussieu, F-75005 Paris (France); Wilkowski, D. [Institut Non Lineaire de Nice, Universite de Nice Sophia-Antipolis, CNRS, F-06560 Valbonne (France); Centre for Quantum Technologies, National University of Singapore, 117543 Singapore (Singapore)

    2011-07-15T23:59:59.000Z

    When a resonant laser sent on an optically thick cold atomic cloud is abruptly switched off, a coherent flash of light is emitted in the forward direction. This transient phenomenon is observed due to the highly resonant character of the atomic scatterers. We analyze quantitatively its temporal properties and show very good agreement with theoretical predictions. Based on complementary experiments, the phase of the coherent field is reconstructed without interferometric tools.

  10. Organic light emitting device having multiple separate emissive layers

    DOE Patents [OSTI]

    Forrest, Stephen R. (Ann Arbor, MI)

    2012-03-27T23:59:59.000Z

    An organic light emitting device having multiple separate emissive layers is provided. Each emissive layer may define an exciton formation region, allowing exciton formation to occur across the entire emissive region. By aligning the energy levels of each emissive layer with the adjacent emissive layers, exciton formation in each layer may be improved. Devices incorporating multiple emissive layers with multiple exciton formation regions may exhibit improved performance, including internal quantum efficiencies of up to 100%.

  11. 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

  12. High-Efficiency and Stable White Organic Light-Emitting Diode...

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

    Efficiency and Stable White Organic Light-Emitting Diode Using a Single Emitter High-Efficiency and Stable White Organic Light-Emitting Diode Using a Single Emitter Presenter: Jian...

  13. 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

  14. 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

  15. auger-electron emitting estrogen: Topics by E-print Network

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

    Ag as anode Institute of Physics. DOI: 10.10631.2172734 Active-matrix organic light-emitting diode AMOLED displays have 63 Interference of spontaneously emitted photons Quantum...

  16. advanced semiconductor light-emitting: Topics by E-print Network

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

    vertical radiation using a two-dimensional photonic crystal in a semiconductor light-emitting diode Engineering Websites Summary: light-emitting diode Alexei A. Erchak,a) Daniel...

  17. Evaluation of potential applications for templated arrays of heterostructural semiconductor nanowires as light emitting devices

    E-Print Network [OSTI]

    Zou, Ting, M. Eng. Massachusetts Institute of Technology

    2006-01-01T23:59:59.000Z

    While light emitting devices, such as laser diodes (LDs) and light emitting diodes (LEDs), were first introduced decades ago, they have been the subject of continuing research and improvements due to their relatively poor ...

  18. 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.

    2010-01-01T23:59:59.000Z

    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.

  19. NEW APPROACHES TO CONFINED ALPHA DIAGNOSTICS

    SciTech Connect (OSTI)

    FISHER,R.K

    2004-04-01T23:59:59.000Z

    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.

  20. 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)

    2004-10-01T23:59:59.000Z

    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.

  1. Nuclear diagnostic for fast alpha particles

    DOE Patents [OSTI]

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

    1983-11-23T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Williams, Roger T.

    1994-01-01T23:59:59.000Z

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

  3. Determination of the 242Pu Branching Ratio via Alpha-Gamma Coincidence

    SciTech Connect (OSTI)

    Wang, T F

    2012-05-24T23:59:59.000Z

    When the burn-up is high, the {sup 242}Pu isotopic content becomes more important. The traditional correlation method will fail. The {sup 242}Pu isotopic content in the sample plays an essential role if the neutron coincidence method is used to quantify the total amount of plutonium. In one of the earlier measurements we had a chance to measure an isotopic pure (> 99.95 %) {sup 242}Pu thick sample and realized that the difference in the branching ratio (BR) value among current nuclear data3) for the two important gamma-rays at 103.5-keV and 158.8-keV. In this study, the thick sample was counted on a 15% ORTEC safeguards type HPGe to further improve BR determination of the 159-keV gamma-ray. Furthermore, we have made a thin {sup 242}Pu sample from the thick sample and performed alpha-gamma coincidence measurements. Our preliminary gamma-ray BR results are 4.37(6) E-4, 2.79(8) E-5, and 2.25(8) E-6 for 44.9-keV, 103.5-keV, and 158.9-keV, respectively.

  4. 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)

    2014-02-17T23:59:59.000Z

    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.

  5. Enhanced light emission from top-emitting organic light-emitting diodes by optimizing surface plasmon polariton losses

    E-Print Network [OSTI]

    Fuchs, Cornelius; Wieczorek, Martin; Gather, Malte C; Hofmann, Simone; Reineke, Sebastian; Leo, Karl; Scholz, Reinhard

    2015-01-01T23:59:59.000Z

    We demonstrate enhanced light extraction for monochrome top-emitting organic light-emitting diodes (OLEDs). The enhancement by a factor of 1.2 compared to a reference sample is caused by the use of a hole transport layer (HTL) material possessing a low refractive index (1.52). The low refractive index reduces the in-plane wave vector of the surface plasmon polariton (SPP) excited at the interface between the bottom opaque metallic electrode (anode) and the HTL. The shift of the SPP dispersion relation decreases the power dissipated into lost evanescent excitations and thus increases the outcoupling efficiency, although the SPP remains constant in intensity. The proposed method is suitable for emitter materials owning isotropic orientation of the transition dipole moments as well as anisotropic, preferentially horizontal orientation, resulting in comparable enhancement factors. Furthermore, for sufficiently low refractive indices of the HTL material, the SPP can be modeled as a propagating plane wave within ot...

  6. Direct radiative effect of aerosols emitted by transport from road, shipping and

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Direct radiative effect of aerosols emitted by transport from road, shipping and aviation 1234567.0 License. Atmospheric Chemistry and Physics Direct radiative effect of aerosols emitted by transport: from ­ Published: 17 May 2010 Abstract. Aerosols and their precursors are emitted abun- dantly by transport

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. Vertical Pillar-Superlattice Array and Graphene Hybrid Light Emitting Diodes

    E-Print Network [OSTI]

    Rogers, John A.

    Vertical Pillar-Superlattice Array and Graphene Hybrid Light Emitting Diodes Jung Min Lee, Jae a class of light emitting diode (LED) with interesting mechanical, optical, and electrical characteristics, light-emitting diodes, 3D architectures, transparent electrodes V ertical arrays of one-dimensional (1D

  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. 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

  1. 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

  2. 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: iamsfchen@njupt.edu.cn, E-mail: wei-huang@njupt.edu.cn; Xu, Ying; Zhao, Xiaofei; Cheng, Fan [Key Laboratory for Organic Electronics and Information Displays (KLOEID) and Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, 210023 Nanjing (China)] [Key Laboratory for Organic Electronics and Information Displays (KLOEID) and Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, 210023 Nanjing (China); Huang, Wei, E-mail: iamsfchen@njupt.edu.cn, E-mail: wei-huang@njupt.edu.cn [Key Laboratory for Organic Electronics and Information Displays (KLOEID) and Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, 210023 Nanjing (China) [Key Laboratory for Organic Electronics and Information Displays (KLOEID) and Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications, 210023 Nanjing (China); Jiangsu-Singapore Joint Research Center for Organic/Bio- Electronics and Information Displays and Institute of Advanced Materials, Nanjing University of Technology, Nanjing 211816 (China)

    2014-04-15T23:59:59.000Z

    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.

  3. Analysis of hydrogen isotope mixtures

    DOE Patents [OSTI]

    Villa-Aleman, Eliel (Aiken, SC)

    1994-01-01T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    Yu, K.N.

    . INTRODUCTION Alpha particles from inhaled radon progeny are the most important source of irradiation

  5. Stable Isotope Signatures for Microbial Forensics

    SciTech Connect (OSTI)

    Kreuzer, Helen W.

    2012-01-03T23:59:59.000Z

    The isotopic distribution of the atoms composing the molecules of microorganisms is a function of the substrates used by the organisms. The stable isotope content of an organism is fixed so long as no further substrate consumption and biosynthesis occurs, while the radioactive isotopic content decays over time. The distribution of stable isotopes of C, N, O and H in heterotrophic microorganisms is a direct function of the culture medium, and therefore the stable isotope composition can be used to associate samples with potential culture media and also with one another. The 14C content depends upon the 14C content, and therefore the age, of the organic components of the culture medium, as well as on the age of the culture itself. Stable isotope signatures can thus be used for sample matching, to associate cultures with specific growth media, and to predict characteristics of growth media.

  6. Stable Isotope Enrichment Capabilities at ORNL

    SciTech Connect (OSTI)

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

    2013-01-01T23:59:59.000Z

    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.

  7. 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

    2014-12-30T23:59:59.000Z

    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.

  8. Alpha Channeling in Rotating Plasma with Stationary Waves

    SciTech Connect (OSTI)

    A. Fetterman and N.J. Fisch

    2010-02-15T23:59:59.000Z

    An extension of the alpha channeling effect to supersonically rotating mirrors shows that the rotation itself can be driven using alpha particle energy. Alpha channeling uses radiofrequency waves to remove alpha particles collisionlessly at low energy. We show that stationary magnetic fields with high n? can be used for this purpose, and simulations show that a large fraction of the alpha energy can be converted to rotation energy.

  9. Stable Isotope Protocols: Sampling and Sample Processing

    E-Print Network [OSTI]

    Levin, Lisa A; Currin, Carolyn

    2012-01-01T23:59:59.000Z

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

  10. 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.

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

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

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

  12. Atom trap trace analysis of krypton isotopes

    SciTech Connect (OSTI)

    Bailey, K.; Chen, C. Y.; Du, X.; Li, Y. M.; Lu, Z.-T.; O'Connor, T. P.; Young, L.

    1999-11-17T23:59:59.000Z

    A new method of ultrasensitive isotope trace analysis has been developed. This method, based on the technique of laser manipulation of neutral atoms, has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton gas sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. This method is free of contamination from other isotopes and elements and can be applied to several different isotope tracers for a wide range of applications. The demonstrated detection efficiency is 1 x 10{sup {minus}7}. System improvements could increase the efficiency by many orders of magnitude.

  13. Stable Isotope Fractionations in Biogeochemical Reactive Transport

    E-Print Network [OSTI]

    Druhan, Jennifer Lea

    2012-01-01T23:59:59.000Z

    34 S fractionation . Summary A mesoscale study of isotopicion exchange and ! 44 Ca . A mesoscale study of isotopicmodeling and ! 34 S . A mesoscale study of isotopic

  14. Method for isotope enrichment by photoinduced chemiionization

    DOE Patents [OSTI]

    Dubrin, James W. (Walnut Creek, CA)

    1985-01-01T23:59:59.000Z

    Isotope enrichment, particularly .sup.235 U enrichment, is achieved by irradiating an isotopically mixed vapor feed with radiant energy at a wavelength or wavelengths chosen to selectively excite the species containing a desired isotope to a predetermined energy level. The vapor feed if simultaneously reacted with an atomic or molecular reactant species capable of preferentially transforming the excited species into an ionic product by a chemiionization reaction. The ionic product, enriched in the desired isotope, is electrostatically or electromagnetically extracted from the reaction system.

  15. THE CHANDRA DEEP PROTOCLUSTER SURVEY: Ly{alpha} BLOBS ARE POWERED BY HEATING, NOT COOLING

    SciTech Connect (OSTI)

    Geach, J. E.; Alexander, D. M.; Lehmer, B. D.; Matsuda, Y. [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Smail, Ian; Bower, R. G. [Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Chapman, S. C. [Institute of Astronomy, Madingley Road, Cambridge, CB3 0HA (United Kingdom); Scharf, C. A.; Bauer, F. E.; Basu-Zych, A. [Columbia Astrophysics Laboratory, Columbia University, Pupin Laboratories, 550 West 120th Street, Room 1418, New York, NY 10027 (United States); Ivison, R. J. [SUPA, Institute for Astronomy, Royal Observatory of Edinburgh, Blackford Hill, Edinburgh, EH9 3HJ (United Kingdom); Volonteri, M. [Department of Astronomy, University of Michigan, Ann Arbor, MI (United States); Yamada, T. [National Astronomical Observatory of Japan, Tokyo 181-8588 (Japan); Blain, A. W. [Department of Astronomy, California Institute of Technology, MC 105-24, 1200, East California Boulevard, Pasadena, CA 91125 (United States)], E-mail: j.e.geach@durham.ac.uk

    2009-07-20T23:59:59.000Z

    We present the results of a 400 ks Chandra survey of 29 extended Ly{alpha} emitting nebulae (Ly{alpha} Blobs, LABs) in the z = 3.09 protocluster in the SS A22 field. We detect luminous X-ray counterparts in five LABs, implying a large fraction of active galactic nuclei (AGN) in LABs, f{sub AGN} = 17{sup +12}{sub -7}% down to L{sub 2-32keV} {approx} 10{sup 44} erg s{sup -1}. All of the AGN appear to be heavily obscured, with spectral indices implying obscuring column densities of N{sub H} > 10{sup 23} cm{sup -2}. The AGN fraction should be considered a lower limit, since several more LABs not detected with Chandra show AGN signatures in their mid-infrared (mid-IR) emission. We show that the UV luminosities of the AGN are easily capable of powering the extended Ly{alpha} emission via photoionization alone. When combined with the UV flux from a starburst component, and energy deposited by mechanical feedback, we demonstrate that 'heating' by a central source, rather than gravitational cooling is the most likely power source of LABs. We argue that all LABs could be powered in this manner, but that the luminous host galaxies are often just below the sensitivity limits of current instrumentation, or are heavily obscured. No individual LABs show evidence for extended X-ray emission, and a stack equivalent to a {approx}>9 Ms exposure of an average LAB also yields no statistical detection of a diffuse X-ray component. The resulting diffuse X-ray/Ly{alpha} luminosity limit implies there is no hot (T {approx}> 10{sup 7} K) gas component in these halos, and also rules out inverse Compton scattering of cosmic microwave background photons, or local far-IR photons, as a viable power source for LABs.

  16. O isotopic composition of CaCO3 measured by continuous ow isotope ratio mass spectrometry

    E-Print Network [OSTI]

    d13 C and d18 O isotopic composition of CaCO3 measured by continuous ¯ow isotope ratio mass. This new method streamlines the classical phosphoric acid/calcium carbonate (H3PO4/CaCO3) reaction method XL continuous flow isotope ratio mass spectrometer. Conditions for which the H3PO4/CaCO3 reaction

  17. 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)

    1994-10-04T23:59:59.000Z

    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.

  18. 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)

    1994-08-02T23:59:59.000Z

    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.

  19. Efficient bottom cathodes for organic light-emitting devices

    SciTech Connect (OSTI)

    Liu Jie; Duggal, Anil R.; Shiang, Joseph J.; Heller, Christian M. [General Electric Global Research, 1 Research Circle, Niskayuna, New York 12309 (United States)

    2004-08-02T23:59:59.000Z

    Bilayers of aluminum and an alkali fluoride are well-known top cathode contacts for organic light-emitting devices but have never been successfully applied as bottom contacts. We describe a bilayer bottom cathode contact for organic electronic devices based on reversing the well-known top cathode structure such that the aluminum, rather than the alkali fluoride, contacts the organic material. Electron-only devices were fabricated showing enhanced electron injection from this bottom contact. Kelvin probe, x-ray photoelectron spectroscopy experiments, and thermodynamic calculations suggest that the enhancement results from n doping of the organic material by dissociated alkali metals.

  20. 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

    2013-05-28T23:59:59.000Z

    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.

  1. Poly (p-phenyleneacetylene) light-emitting diodes

    DOE Patents [OSTI]

    Shinar, J.; Swanson, L.S.; Lu, F.; Ding, Y.; Barton, T.J.; Vardeny, Z.V.

    1994-10-04T23:59:59.000Z

    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.

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

    DOE Patents [OSTI]

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

    1994-08-02T23:59:59.000Z

    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.

  3. Graphene surface emitting terahertz laser: Diffusion pumping concept

    SciTech Connect (OSTI)

    Davoyan, Arthur R., E-mail: davoyan@seas.upenn.edu [Kotelnikov Institute of Radio Engineering and Electronics (Saratov Branch), Russian Academy of Sciences, Saratov 410019, Russia and Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Morozov, Mikhail Yu.; Popov, Vyacheslav V. [Kotelnikov Institute of Radio Engineering and Electronics (Saratov Branch), Russian Academy of Sciences, Saratov 410019 (Russian Federation)] [Kotelnikov Institute of Radio Engineering and Electronics (Saratov Branch), Russian Academy of Sciences, Saratov 410019 (Russian Federation); Satou, Akira; Otsuji, Taiichi [Research Institute of Electrical Communication (RIEC), Tohoku University, Sendai, Miyagi 980-8577 (Japan)] [Research Institute of Electrical Communication (RIEC), Tohoku University, Sendai, Miyagi 980-8577 (Japan)

    2013-12-16T23:59:59.000Z

    We suggest a concept of a tunable graphene-based terahertz (THz) surface emitting laser with diffusion pumping. We employ significant difference in the electronic energy gap of graphene and a typical wide-gap semiconductor, and demonstrate that carriers generated in the semiconductor can be efficiently captured by graphene resulting in population inversion and corresponding?THz lasing from graphene. We develop design principles for such a laser and estimate its performance. We predict up to 50?W/cm{sup 2} terahertz power output for 100?kW/cm{sup 2} pump power at frequency around 10?THz at room temperature.

  4. 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)

    1992-01-01T23:59:59.000Z

    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.

  5. Solid-state radiation-emitting compositions and devices

    DOE Patents [OSTI]

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

    1992-08-11T23:59:59.000Z

    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.

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

    E-Print Network [OSTI]

    M. Thoennessen

    2012-03-09T23:59:59.000Z

    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.

  7. Gamma Spectrum from Neutron Capture on Tungsten Isotopes

    E-Print Network [OSTI]

    Hurst, Aaron

    2011-01-01T23:59:59.000Z

    FROM NEUTRON CAPTURE ON TUNGSTEN ISOTOPES A. M. HURST ?1,2 ,capture on the stable tungsten isotopes is presented, withknown decay schemes of the tungsten isotopes from neutron

  8. 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)

    1986-01-01T23:59:59.000Z

    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.

  9. Synthesis of peptide .alpha.-thioesters

    DOE Patents [OSTI]

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

    2008-08-19T23:59:59.000Z

    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.

  10. Alternating current long range alpha particle detector

    DOE Patents [OSTI]

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

    1993-02-16T23:59:59.000Z

    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.

  11. Tropical Pacific nutrient dynamics in the modern and pleistocene ocean : insights from the nitrogen isotope system

    E-Print Network [OSTI]

    Rafter, Patrick Anthony

    2009-01-01T23:59:59.000Z

    nitrogen isotopes, an enrichment that is conventionallyisotopes upon denitrification also imparts a strong isotopic enrichment

  12. Organic light-emitting devices using spin-dependent processes

    DOE Patents [OSTI]

    Vardeny, Z. Valy (Salt Lake City, UT); Wohlgenannt, Markus (Salt Lake City, UT)

    2010-03-23T23:59:59.000Z

    The maximum luminous efficiency of organic light-emitting materials is increased through spin-dependent processing. The technique is applicable to all electro-luminescent processes in which light is produced by singlet exciton decay, and all devices which use such effects, including LEDs, super-radiant devices, amplified stimulated emission devices, lasers, other optical microcavity devices, electrically pumped optical amplifiers, and phosphorescence (Ph) based light emitting devices. In preferred embodiments, the emissive material is doped with an impurity, or otherwise modified, to increase the spin-lattice relaxation rate (i.e., decrease the spin-lattice time), and hence raise the efficiency of the device. The material may be a polymer, oligomer, small molecule, single crystal, molecular crystal, or fullerene. The impurity is preferably a magnetic or paramagnetic substance. The invention is applicable to IR, UV, and other electromagnetic radiation generation and is thus not limited to the visible region of the spectrum. The methods of the invention may also be combined with other techniques used to improve device performance.

  13. Monitoring lensed starlight emitted close to the Galactic Center

    E-Print Network [OSTI]

    Adi Nusser; Tom Broadhurst

    2004-07-12T23:59:59.000Z

    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.

  14. 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)

    2013-12-15T23:59:59.000Z

    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.

  15. Isotopic Scaling in Nuclear Reactions

    E-Print Network [OSTI]

    M. B. Tsang; W. A. Friedman; C. K. Gelbke; W. G. Lynch; G. Verde; H. Xu

    2001-03-26T23:59:59.000Z

    A three parameter scaling relationship between isotopic distributions for elements with Z$\\leq 8$ has been observed that allows a simple description of the dependence of such distributions on the overall isospin of the system. This scaling law (termed iso-scaling) applies for a variety of reaction mechanisms that are dominated by phase space, including evaporation, multifragmentation and deeply inelastic scattering. The origins of this scaling behavior for the various reaction mechanisms are explained. For multifragmentation processes, the systematics is influenced by the density dependence of the asymmetry term of the equation of state.

  16. Fan-less long range alpha detector

    DOE Patents [OSTI]

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

    1994-05-10T23:59:59.000Z

    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.

  17. Lunar surface outgassing and alpha particle measurements

    SciTech Connect (OSTI)

    Lawson, S. L. (Stefanie L.); Feldman, W. C. (William C.); Lawrence, David J. (David Jeffery),; Moore, K. R. (Kurt R.); Elphic, R. C. (Richard C.); Maurice, S. (Sylvestre); Belian, Richard D.; Binder, Alan B.

    2002-01-01T23:59:59.000Z

    The Lunar Prospector Alpha Particle Spectrometer (LP APS) searched for lunar surface gas release events and mapped their distribution by detecting alpha particle?; produced by the decay of gaseous radon-222 (5.5 MeV, 3.8 day half-life), solid polonium-2 18 (6.0 MeV, 3 minute half-life), and solid polonium-210 (5.3 MeV, 138 day half-life, but held up in production by the 21 year half-life of lead-210). These three nuclides are radioactive daughters from the decay of uranium-238.

  18. 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.

    2010-01-01T23:59:59.000Z

    carbon and nitrogen isotope enrichment in primate tissuesfactor (a) and isotope enrichment values (e), which provideisotope values from different modern primate tissues. Additionally, using these mean apparent enrichment

  19. CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope...

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

    Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor Contractor ORR CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor Contractor ORR...

  20. CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope...

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

    Oak Ridge National Laboratory High Flux Isotope Reactor CRAD, Engineering - Oak Ridge National Laboratory High Flux Isotope Reactor February 2007 A section of Appendix C to DOE G...

  1. aluminium isotopes: Topics by E-print Network

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

    CERN Preprints Summary: Currently, 31 actinium, 31 thorium, 28 protactinium, and 23 uranium isotopes have so far been observed; the discovery of these isotopes is discussed. For...

  2. americium isotopes: Topics by E-print Network

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

    CERN Preprints Summary: Currently, 31 actinium, 31 thorium, 28 protactinium, and 23 uranium isotopes have so far been observed; the discovery of these isotopes is discussed. For...

  3. activated bismuth isotopes: Topics by E-print Network

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

    CERN Preprints Summary: Currently, 31 actinium, 31 thorium, 28 protactinium, and 23 uranium isotopes have so far been observed; the discovery of these isotopes is discussed. For...

  4. astatine isotopes: Topics by E-print Network

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

    CERN Preprints Summary: Currently, 31 actinium, 31 thorium, 28 protactinium, and 23 uranium isotopes have so far been observed; the discovery of these isotopes is discussed. For...

  5. A Helium Isotope Perspective On The Dixie Valley, Nevada, Hydrothermal...

    Open Energy Info (EERE)

    Helium Isotope Perspective On The Dixie Valley, Nevada, Hydrothermal System Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: A Helium Isotope...

  6. Isotopic Analysis- Fluid At Dixie Valley Geothermal Area (Kennedy...

    Open Energy Info (EERE)

    geothermal resources with deep, fault hosted permeable fluid flow pathways and the helium Isotopic composition of the surface fluids. The authors suggest that helium isotopes...

  7. Fractionation of Oxygen Isotopes in Phosphate during its Interactions...

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

    Fractionation of Oxygen Isotopes in Phosphate during its Interactions with Iron Oxides. Fractionation of Oxygen Isotopes in Phosphate during its Interactions with Iron Oxides....

  8. applied isotope techniques: Topics by E-print Network

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

    M. 22 Applied Radiation and Isotopes 55 (2001) 707713 Bronchial dosimeter for radon progeny Biology and Medicine Websites Summary: Applied Radiation and Isotopes 55 (2001)...

  9. Mapping High-velocity H-alpha and Lyman-alpha Emission from Supernova 1987A

    E-Print Network [OSTI]

    France, Kevin; Fransson, Claes; Larsson, Josefin; Frank, Kari A; Burrows, David N; Challis, Peter; Kirshner, Robert P; Chevalier, Roger A; Garnavich, Peter; Heng, Kevin; Lawrence, Stephen S; Lundqvist, Peter; Smith, Nathan; Sonneborn, George

    2015-01-01T23:59:59.000Z

    We present new {\\it Hubble Space Telescope} images of high-velocity H-$\\alpha$ and Lyman-$\\alpha$ emission in the outer debris of SN~1987A. The H-$\\alpha$ images are dominated by emission from hydrogen atoms crossing the reverse shock. For the first time we observe emission from the reverse shock surface well above and below the equatorial ring, suggesting a bipolar or conical structure perpendicular to the ring plane. Using the H$\\alpha$ imaging, we measure the mass flux of hydrogen atoms crossing the reverse shock front, in the velocity intervals ($-$7,500~$<$~$V_{obs}$~$<$~$-$2,800 km s$^{-1}$) and (1,000~$<$~$V_{obs}$~$<$~7,500 km s$^{-1}$), $\\dot{M_{H}}$ = 1.2~$\\times$~10$^{-3}$ M$_{\\odot}$ yr$^{-1}$. We also present the first Lyman-$\\alpha$ imaging of the whole remnant and new $Chandra$ X-ray observations. Comparing the spatial distribution of the Lyman-$\\alpha$ and X-ray emission, we observe that the majority of the high-velocity Lyman-$\\alpha$ emission originates interior to the equatorial...

  10. Advanced Mass Spectrometers for Hydrogen Isotope Analyses

    SciTech Connect (OSTI)

    Chastagner, P.

    2001-08-01T23:59:59.000Z

    This report is a summary of the results of a joint Savannah River Laboratory (SRL) - Savannah River Plant (SRP) ''Hydrogen Isotope Mass Spectrometer Evaluation Program''. The program was undertaken to evaluate two prototype hydrogen isotope mass spectrometers and obtain sufficient data to permit SRP personnel to specify the mass spectrometers to replace obsolete instruments.

  11. Positive and inverse isotope effect on superconductivity

    E-Print Network [OSTI]

    Tian De Cao

    2009-09-04T23:59:59.000Z

    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.

  12. MARK E. CONRAD Center for Isotope Geochemistry

    E-Print Network [OSTI]

    Ajo-Franklin, Jonathan

    with stable isotopes, fate and transport of groundwater contaminants, vadose zone hydrology, metal uptake by lichens, paleoclimatic patterns in California and stable isotope systematics of clay minerals. Geologist of gold property in the Mother Lode of California. Exploration Geologist (Anaconda Minerals Company; 6

  13. The Quest for the Heaviest Uranium Isotope

    E-Print Network [OSTI]

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

    2012-01-17T23:59:59.000Z

    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.

  14. Isotope separation by selective photodissociation of glyoxal

    DOE Patents [OSTI]

    Marling, John B. (Pleasanton, CA)

    1976-01-01T23:59:59.000Z

    Dissociation products, mainly formaldehyde and carbon monoxide, enriched in a desired isotope of carbon, oxygen, or hydrogen are obtained by the selective photodissociation of glyoxal wherein glyoxal is subjected to electromagnetic radiation of a predetermined wavelength such that photon absorption excites and induces dissociation of only those molecules of glyoxal containing the desired isotope.

  15. [Carbon isotope fractionation inplants]. Final report

    SciTech Connect (OSTI)

    O`Leary, M.H.

    1990-12-31T23:59:59.000Z

    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.

  16. RAPID DETERMINATION OF ACTINIDES IN URINE BY INDUCTIVELY-COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY: A HYBRID APPROACH

    SciTech Connect (OSTI)

    Maxwell, S.; Jones, V.

    2009-05-27T23:59:59.000Z

    A new rapid separation method that allows separation and preconcentration of actinides in urine samples was developed for the measurement of longer lived actinides by inductively coupled plasma mass spectrometry (ICP-MS) and short-lived actinides by alpha spectrometry; a hybrid approach. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration, if required, is performed using a streamlined calcium phosphate precipitation. Similar technology has been applied to separate actinides prior to measurement by alpha spectrometry, but this new method has been developed with elution reagents now compatible with ICP-MS as well. Purified solutions are split between ICP-MS and alpha spectrometry so that long- and short-lived actinide isotopes can be measured successfully. The method allows for simultaneous extraction of 24 samples (including QC samples) in less than 3 h. Simultaneous sample preparation can offer significant time savings over sequential sample preparation. For example, sequential sample preparation of 24 samples taking just 15 min each requires 6 h to complete. The simplicity and speed of this new method makes it attractive for radiological emergency response. If preconcentration is applied, the method is applicable to larger sample aliquots for occupational exposures as well. The chemical recoveries are typically greater than 90%, in contrast to other reported methods using flow injection separation techniques for urine samples where plutonium yields were 70-80%. This method allows measurement of both long-lived and short-lived actinide isotopes. 239Pu, 242Pu, 237Np, 243Am, 234U, 235U and 238U were measured by ICP-MS, while 236Pu, 238Pu, 239Pu, 241Am, 243Am and 244Cm were measured by alpha spectrometry. The method can also be adapted so that the separation of uranium isotopes for assay is not required, if uranium assay by direct dilution of the urine sample is preferred instead. Multiple vacuum box locations may be set-up to supply several ICP-MS units with purified sample fractions such that a high sample throughput may be achieved, while still allowing for rapid measurement of short-lived actinides by alpha spectrometry.

  17. Transformer Recharging with Alpha Channeling in Tokamaks

    SciTech Connect (OSTI)

    N.J. Fisch

    2009-12-21T23:59:59.000Z

    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. __________________________________________________

  18. ISOTOPES

    E-Print Network [OSTI]

    Lederer, C. Michael

    2013-01-01T23:59:59.000Z

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

  19. ISOTOPES

    E-Print Network [OSTI]

    Lederer, C. Michael

    2013-01-01T23:59:59.000Z

    lithium hydroxide (56, 14), A plant utilizing this reaction to produce 1000 kg per year of 99.99% 7Li at a price

  20. ISOTOPES

    E-Print Network [OSTI]

    Lederer, C. Michael

    2013-01-01T23:59:59.000Z

    §fissile materials in fast breeder reactors currently underwater reactor, FBR = fast breeder reactor. The band belowinc 1 udes heavy-water reactors, fast breeders, and 11

  1. ISOTOPES

    E-Print Network [OSTI]

    Lederer, C. Michael

    2013-01-01T23:59:59.000Z

    1978). United States Gas Centrifuge Program for 72. Energy~~;h)radius in a gas centrifuge with va 400 m/s. P 0 and U68,14) of a gas centrifuge with radius = 0.09145 m, length=

  2. ISOTOPES

    E-Print Network [OSTI]

    Lederer, C. Michael

    2013-01-01T23:59:59.000Z

    the columns used to separate UF5, which had a separativeof uranium by dissociation of UF5, by multiple vibrational

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

    DOE Patents [OSTI]

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

    1999-08-31T23:59:59.000Z

    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.

  4. 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)

    1999-01-01T23:59:59.000Z

    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. 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)

    1992-01-01T23:59:59.000Z

    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.

  6. 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 [Y?ld?z Technical University, Department of Physics, Esenler, Istanbul (Turkey); Tekin, Emine; Pravadal?, Selin [National Metrology Inst?tute of Turkey (TUB?TAK-UME), Kocaeli (Turkey)

    2013-12-16T23:59:59.000Z

    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.

  7. Thermal properties of organic light-emitting diodes

    SciTech Connect (OSTI)

    Bergemann, Kevin; Krasny, Robert; Forrest, Stephen R.

    2012-01-01T23:59:59.000Z

    Thermal management is important for the efficient operation of organic light-emitting diodes (OLED, or PHOLED) at high brightness, with the device operating temperature influencing both lifetime and performance. We apply a transmission-matrix approach to analytically model the effects of thermal conduction, convection and radiation on OLED temperature. The model predictions match experiment without requiring the use of fitting parameters. This allows for the simulation of the thermal response of various device architectures, materials combinations and environmental factors under a variety of operating conditions. Using these simulations, we find that 87% of the heat is dissipated through the air space adjacent to the glass package cap. Furthermore, an air gap between the device cathode and cap provides a significant thermal impedance. Minimizing the thickness of the internal air gap can lead to nearly room temperature operation, even at very high brightness.

  8. Mid-ultraviolet light-emitting diode detects dipicolinic acid.

    SciTech Connect (OSTI)

    Bogart, Katherine Huderle Andersen; Lee, Stephen Roger; Temkin, Henryk (Texas Tech University, Lubbock, TX); Crawford, Mary Hagerott; Dasgupta, Purnendu K. (Texas Tech University, Lubbock, TX); Li, Qingyang (Texas Tech University, Lubbock, TX); Allerman, Andrew Alan; Fischer, Arthur Joseph

    2005-06-01T23:59:59.000Z

    Dipicolinic acid (DPA, 2,6-pyridinedicarboxylic acid) is a substance uniquely present in bacterial spores such as that from anthrax (B. anthracis). It is known that DPA can be detected by the long-lived fluorescence of its terbium chelate; the best limit of detection (LOD) reported thus far using a large benchtop gated fluorescence instrument using a pulsed Xe lamp is 2 nM. We use a novel AlGaN light-emitting diode (LED) fabricated on a sapphire substrate that has peak emission at 291 nm. Although the overlap of the emission band of this LED with the absorption band of Tb-DPA ({lambda}{sub max} doublet: 273, 279 nm) is not ideal, we demonstrate that a compact detector based on this LED and an off-the-shelf gated photodetection module can provide an LOD of 0.4 nM, thus providing a basis for convenient early warning detectors.

  9. 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)

    2012-02-14T23:59:59.000Z

    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.

  10. Model for Triplet State Engineering in Organic Light Emitting Diodes

    E-Print Network [OSTI]

    Prodhan, Suryoday; Ramasesha, S

    2014-01-01T23:59:59.000Z

    Engineering the position of the lowest triplet state (T1) relative to the first excited singlet state (S1) is of great importance in improving the efficiencies of organic light emitting diodes and organic photovoltaic cells. We have carried out model exact calculations of substituted polyene chains to understand the factors that affect the energy gap between S1 and T1. The factors studied are backbone dimerisation, different donor-acceptor substitutions and twisted geometry. The largest system studied is an eighteen carbon polyene which spans a Hilbert space of about 991 million. We show that for reverse intersystem crossing (RISC) process, the best system involves substituting all carbon sites on one half of the polyene with donors and the other half with acceptors.

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

    E-Print Network [OSTI]

    Reineke, Sebastian; Lüssem, Björn; Leo, Karl

    2013-01-01T23:59:59.000Z

    White organic light-emitting diodes (OLEDs) are ultra-thin, large-area light sources made from organic semiconductor materials. Over the last decades, much research has been spent on finding the suitable materials to realize highly efficient monochrome and white OLEDs. With their high efficiency, color-tunability, and color-quality, white OLEDs are emerging to become one of the next generation light sources. In this review, we discuss the physics of a variety of device concepts that are introduced to realize white OLEDs based on both polymer and small molecule organic materi als. Owing to the fact that about 80 % of the internally generated photons are trapped within the thin-film layer structure, we put a second focus on reviewing promising concepts for improved light outcoupling.

  12. 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

    2011-01-01T23:59:59.000Z

    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.

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

    DOE Patents [OSTI]

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

    2009-08-25T23:59:59.000Z

    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).

  14. Nuclear Half-Lives for Alpha Radioactivity of Elements with 100 $\\leq$ Z $\\leq$ 130

    E-Print Network [OSTI]

    P. Roy Chowdhury; C. Samanta; D. N. Basu

    2008-02-29T23:59:59.000Z

    Theoretical estimates for the half lives of about 1700 isotopes of heavy elements with Z from 100 to 130 are tabulated using theoretical Q-values. The quantum mechanical tunneling probabilities are calculated within a WKB framework using microscopic nuclear potentials. The microscopic nucleus-nucleus potentials are obtained by folding the densities of interacting nuclei with a density dependent M3Y (DDM3Y) effective nucleon-nucleon interaction. The alpha-decay half lives calculated in this formalism using the experimental Q-values were found to be in good agreement over a wide range of experimental data spanning about twenty orders of magnitude. The theoretical Q-values used for the present calculations are extracted from three different mass estimates viz. Myers-Swiatecki [MS], Muntian-Hofmann-Patyk-Sobiczewski [M] and Koura-Tachibana-Uno-Yamada [KUTY].

  15. Running alpha(s) from Landau-gauge gluon and ghost correlations

    E-Print Network [OSTI]

    A. Sternbeck; E. -M. Ilgenfritz; K. Maltman; M. Müller-Preussker; L. von Smekal; A. G. Williams

    2007-10-16T23:59:59.000Z

    We estimate the running coupling constant of the strong interactions within the nonperturbative framework of lattice QCD in Landau gauge. Our calculation is based on the ghost-gluon vertex which in the particular case of Landau gauge allows for a definition of alpha(s) in a MOM scheme solely in terms of the gluon and ghost dressing functions. As a first step we investigate the zero and two-flavour case and report here on preliminary results.

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

    SciTech Connect (OSTI)

    Maxwell, S.

    2010-07-26T23:59:59.000Z

    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.

  17. Construction of Building 9201-1 (Alpha 1) - part 2

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

    2 Even while Building 9201-1 (Alpha 1) was being constructed, the first experimental Alpha unit (XAX) in Building 9731 successfully operated, after a week of start up efforts, on...

  18. Alpha phase precipitation from phase-separated beta phase in...

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

    Alpha phase precipitation from phase-separated beta phase in a model Ti-Mo-Al alloy studied by direct coupling of transmission Alpha phase precipitation from phase-separated beta...

  19. Study of alpha background in a dark matter detector

    E-Print Network [OSTI]

    Yegoryan, Hayk

    2010-01-01T23:59:59.000Z

    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 ...

  20. alpha darbepoetine epo: Topics by E-print Network

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

    Phenomenology (arXiv) Summary: In the framework of nonrelativistic QCD, we compute the leading double-logarithmic corrections of order alphas3 ln2(1alphas) to the...

  1. alpha dinucleotide repeat: Topics by E-print Network

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

    Institute 12;www.rpi.edu Alpha Epsilon Lambda Alpha Sigma Chapter Co-terminal Honor Society Rensselaer Polytechnic Institute Chapter President Chaz Goodwine goodwc2@rpi.edu...

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

    DOE Patents [OSTI]

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

    1998-06-09T23:59:59.000Z

    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.

  3. alpha particle counting: Topics by E-print Network

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

    Francesco Giudice; Ben Gripaios; Rakhi Mahbubani 2011-08-08 5 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  4. alpha particles progress: Topics by E-print Network

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

    17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  5. alpha particle diagnostics: Topics by E-print Network

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

    kW, 140 GHz gyrotron tubes used with the Joint Egedal, Jan 3 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  6. alpha particle preformation: Topics by E-print Network

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

    output intensity of a Raman amplifier and the optimal 3 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  7. alpha particles: Topics by E-print Network

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

    17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  8. alpha particles biological effects: Topics by E-print Network

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

    streams in interplanetary space. Bo Li; Xing Li 2006-06-07 8 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  9. alpha particles aberraciones: Topics by E-print Network

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

    17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  10. alpha particle analysis: Topics by E-print Network

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

    17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  11. alpha particle induced: Topics by E-print Network

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

    F. L. Roman; V. Avrigeanu; W. von Oertzen 2008-08-05 7 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  12. alpha particles due: Topics by E-print Network

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

    17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  13. alpha particle transfer: Topics by E-print Network

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

    their transferring energy to the wave. This could, in turn 2 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  14. alpha particle destabilization: Topics by E-print Network

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

    their theoretical predictions 1,2, toroidicity-induced 2 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  15. alpha particle scattering: Topics by E-print Network

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

    particle condensation. S. Ohkubo; Y. Hirabayashi 2011-02-11 5 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  16. alpha particle orbits: Topics by E-print Network

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

    17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  17. alpha particle effects: Topics by E-print Network

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

    streams in interplanetary space. Bo Li; Xing Li 2006-06-07 8 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  18. alpha particles final: Topics by E-print Network

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

    17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  19. alpha particle spectra: Topics by E-print Network

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

    angles. Sergei P. Maydanyuk; Sergei V. Belchikov 2004-12-22 3 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  20. alpha particle radioimmunotherapy: Topics by E-print Network

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

    in tissues (<100 micrometer) (more) Bck, Tom 2011-01-01 2 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  1. alpha particle diagnostic: Topics by E-print Network

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

    kW, 140 GHz gyrotron tubes used with the Joint Egedal, Jan 3 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  2. alpha particle spectroscopy: Topics by E-print Network

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

    17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Nuclear Alpha-Particle Condensates Nuclear Experiment (arXiv) Summary: The alpha-particle condensate in nuclei is...

  3. alpha phase dipalmitoylphosphatidylcholine: Topics by E-print...

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

    Lyman Alpha Radiative Transfer in a Multi-Phase Medium Astrophysics (arXiv) Summary: Hydrogen Ly-alpha is our primary emission-line window into high redshift galaxies....

  4. 2014-05-16 Issuance: Test Procedures for Integrated Light-Emitting...

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

    16 Issuance: Test Procedures for Integrated Light-Emitting Diode Lamps; Supplemental Notice of Proposed Rulemaking 2014-05-16 Issuance: Test Procedures for Integrated...

  5. algainp light-emitting diodes: Topics by E-print Network

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

    materials for different organic layers, which compose the standard organic light emitting diode (OLED) architecture.; Chapter one introduces (more) Borek, Carsten 2008-01-01...

  6. Wire-shaped semiconductor light-emitting diodes for general-purpose lighting

    SciTech Connect (OSTI)

    Mauk, Michael G.

    2002-10-28T23:59:59.000Z

    The object of this work is to develop and optimize a new type of light-emitting diode (LED) with a wire-shaped, cylindrical geometry.

  7. 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...

  8. Discussion of Alpha Particle Physics Issues for AT Burning Plasmas

    E-Print Network [OSTI]

    machines » Projections to burning plasma #12;Alpha self-heating in AT regimes v Production and control

  9. Modifications of alpha processing software to improve calculation of limits for qualitative detection

    SciTech Connect (OSTI)

    Kirkpatrick, J.R.

    1997-01-01T23:59:59.000Z

    The work described in this report was done for the Bioassay Counting Laboratory (BCL) of the Center of Excellence for Bioassay of the Analytical Services Organization at the Oak Ridge Y-12 Plant. BCL takes urine and fecal samples and tests for alpha radiation. An automated system, supplied by Canberra Industries, counts the activities in the samples and processes the results. The Canberra system includes hardware and software. The managers of BCL want to improve the accuracy of the results they report to their final customers. The desired improvements are of particular interest to the managers of BCL because the levels of alpha-emitting radionuclides in samples measured at BCL are usually so low that a significant fraction of the measured signal is due to background and to the reagent material used to extract the radioactive nuclides from the samples. Also, the background and reagent signals show a significant level of random variation. The customers at BCL requested four major modifications of the software. The requested software changes have been made and tested. The present report is in two parts. The first part describes what the modifications were supposed to accomplish. The second part describes the changes on a line-by-line basis. The second part includes listings of the changed software and discusses possible steps to correct a particular error condition. Last, the second part describes the effect of truncation errors on the standard deviations calculated from samples whose signals are very nearly the same.

  10. CHARGE-EXCHANGE LIMITS ON LOW-ENERGY {alpha}-PARTICLE FLUXES IN SOLAR FLARES

    SciTech Connect (OSTI)

    Hudson, H. S. [SSL, UC Berkeley, CA 94720 (United States); Fletcher, L.; MacKinnon, A. L. [School of Physics and Astronomy, SUPA, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Woods, T. N., E-mail: hhudson@ssl.berkeley.edu [Laboratory for Atmospheric and Space Physics, University of Colorado, 1234 Innovation Dr., Boulder, CO 80303 (United States)

    2012-06-20T23:59:59.000Z

    This paper reports on a search for flare emission via charge-exchange radiation in the wings of the Ly{alpha} line of He II at 304 A, as originally suggested for hydrogen by Orrall and Zirker. Via this mechanism a primary {alpha} particle that penetrates into the neutral chromosphere can pick up an atomic electron and emit in the He II bound-bound spectrum before it stops. The Extreme-ultraviolet Variability Experiment on board the Solar Dynamics Observatory gives us our first chance to search for this effect systematically. The Orrall-Zirker mechanism has great importance for flare physics because of the essential roles that particle acceleration plays; this mechanism is one of the few proposed that would allow remote sensing of primary accelerated particles below a few MeV nucleon{sup -1}. We study 10 events in total, including the {gamma}-ray events SOL2010-06-12 (M2.0) and SOL2011-02-24 (M3.5) (the latter a limb flare), seven X-class flares, and one prominent M-class event that produced solar energetic particles. The absence of charge-exchange line wings may point to a need for more complete theoretical work. Some of the events do have broadband signatures, which could correspond to continua from other origins, but these do not have the spectral signatures expected from the Orrall-Zirker mechanism.

  11. 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

    2012-09-27T23:59:59.000Z

    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).

  12. Isotopic composition of Silurian seawater

    SciTech Connect (OSTI)

    Knauth, L.P.; Kealy, S.; Larimer, S.

    1985-01-01T23:59:59.000Z

    Direct isotopic analyses of 21 samples of the Silurian hydrosphere preserved as fluid inclusions in Silurian halite deposits in the Michigan Basin Salina Group yield delta/sup 18/O, deltaD ranging from 0.2 to +5.9 and -26 to -73, respectively. delta/sup 18/O has the same range as observed for modern halite facies evaporite waters and is a few per thousand higher than 100 analyses of fluid inclusions in Permian halite. deltaD is about 20 to 30 per thousand lower than modern and Permian examples. The trajectory of evaporating seawater on a deltaD-delta/sup 18/O diagram initially has a positive slope of 3-6, but hooks strongly downward to negative values, the shape of the hook depending upon humidity. Halite begins to precipitate at delta values similar to those observed for the most /sup 18/O rich fluid inclusions. Subsequent evaporation yields progressively more negative delta values as observed for the fluid inclusions. The fluid inclusion data can be readily explained in terms of evaporating seawater and are consistent with the degree of evaporation deduced from measured bromide profiles. These data are strongly inconsistent with arguments that Silurian seawater was 5.5 per thousand depleted in /sup 18/O. delta/sup 18/O for evaporite waters is systematically related to that of seawater, and does not show a -5.5 per thousand shift in the Silurian, even allowing for variables which affect the isotope evaporation trajectory. The lower deltaD may indicate a component of gypsum dehydration waters or may suggest a D-depleted Silurian hydrosphere.

  13. Comparison of isotopic transmutation modelling codes

    E-Print Network [OSTI]

    Beard, Carl Allen

    1990-01-01T23:59:59.000Z

    . Numerical solutions to the equations that govern isotopic transmutation can be obtained in several ways. Each method possesses a certain amount of intrinsic error which is inherent in the solution scheme, but which can also vary depending upon... of the removed nuclide if it falls between two long-lived isotopes, or by adding the initial concentration of the short-lived isotope to the first long-lived nuclide which occurs in the production chain. In this second case, the final contribution from...

  14. Theory of the helium isotope shift

    E-Print Network [OSTI]

    Yerokhin, Vladimir A

    2015-01-01T23:59:59.000Z

    Theory of the isotope shift of the centroid energies of light few-electron atoms is reviewed. Numerical results are presented for the isotope shift of the $2^3P$-$2^3S$ and $2^1S$-$2^3S$ transition energies of $^3$He and $^4$He. By comparing theoretical predictions for the isotope shift with the experimental results, the difference of the squares of the nuclear charge radii of $^3$He and $^4$He, $\\delta R^2$, is determined with high accuracy.

  15. Helium isotopes in historical lavas from Mount Vesuvius Comment on `Noble gas isotopic ratios from historical lavas

    E-Print Network [OSTI]

    Graham, David W.

    Discussion Helium isotopes in historical lavas from Mount Vesuvius Comment on `Noble gas isotopic. Introduction Helium isotope results recently published by Tedesco et al. [1] appear to show a decrease in 3 He. Results Helium isotope results from our laboratory are reported in Table 1. The 3 He/4 He ratio has been

  16. The acoustic spectrum of alpha Cen A

    E-Print Network [OSTI]

    F. Bouchy; F. Carrier

    2002-06-04T23:59:59.000Z

    This paper presents the analysis of Doppler p-mode observations of the G2V star $\\alpha$ Cen A obtained with the spectrograph CORALIE in May 2001. Thirteen nights of observations have made it possible to collect 1850 radial velocity measurements with a standard deviation of about 1.5 m s$^{-1}$. Twenty-eight oscillation modes have been identified in the power spectrum between 1.8 and 2.9 mHz with amplitudes in the range 12 to 44 cm s$^{-1}$. The average large and small spacing are respectively equal to 105.5 and 5.6 $\\mu$Hz. A comparison with stellar models of $\\alpha$ Cen A is presented.

  17. Automatically processed alpha-track radon monitor

    DOE Patents [OSTI]

    Langner, G.H. Jr.

    1993-01-12T23:59:59.000Z

    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.

  18. 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

    2013-01-01T23:59:59.000Z

    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.

  19. Electron Screening and Alpha-Decay

    E-Print Network [OSTI]

    Agatino Musumarra

    2010-10-21T23:59:59.000Z

    The interplay between nuclear and electromagnetic forces in astrophysical relevant reactions at very low energies is nowadays one of the major subjects of investigation in nuclear astrophysics. Puzzling results concerning the role of Electron Screening (ES) on cross sections of reactions involving light nuclei at low energy open a Pandora pot and many new questions rise on the limits and reliability of the present interpretation of the screening enhancement factor. In the present paper we discuss the simplest physical case where the ES plays an important role in order to have unambiguous determination of ES energy in a clear theoretical scenario. This is the case of alpha-decay of heavy mass nuclei. We deduce the correct sudden and adiabatic limit for such a system including the important relativistic corrections. Then we demonstrate rigorously how in this case the calculation of the sudden and the adiabatic limits leads to the same result. In order to get this result we use the Hellmann-Feynman theorem. After computing the electron screening energy for some systems we discuss the strong modifications of alpha-decay systematic due to electron screening. We conclude proposing a measurement of alpha-decay lifetime of bare nuclei in order to directly deduce ES Energy for heavy nuclei laying in the mass region around 210-240 u.

  20. $\\alpha$ Centauri A in the far infrared

    E-Print Network [OSTI]

    Liseau, R; Olofsson, G; Bryden, G; Marshall, J P; Ardila, D; Aran, A Bayo; Danchi, W C; del Burgo, C; Eiroa, C; Ertel, S; Fridlund, M C W; Krivov, A V; Pilbratt, G L; Roberge, A; Thébault, P; Wiegert, J; White, G J

    2012-01-01T23:59:59.000Z

    Chromospheres and coronae are common phenomena on solar-type stars. Understanding the energy transfer to these heated atmospheric layers requires direct access to the relevant empirical data. Study of these structures has, by and large, been limited to the Sun thus far. The region of the temperature reversal can be directly observed only in the far infrared and submm. We aim at the determination of the characteristics of the atmosphere in the region of the temperature minimum of the solar sister star alpha Cen A. For the nearby binary system alpha Centauri, stellar parameters are known with high accuracy from measurements. For the basic model parameters Teff, log g and [Fe/H], we interpolate in the grid of GAIA/PHOENIX stellar model atmospheres and compute the corresponding model for the G2 V star alpha Cen A. Comparison with photometric measurements shows excellent agreement between observed photospheric data in the optical and infrared. For longer wavelengths, the modelled spectral energy distribution is co...

  1. Lyman-alpha Absorption from Heliosheath Neutrals

    E-Print Network [OSTI]

    Brian E. Wood; Vladislav V. Izmodenov; Jeffrey L. Linsky; Yury G. Malama

    2006-11-30T23:59:59.000Z

    We assess what information HST observations of stellar Ly-alpha lines can provide on the heliosheath, the region of the heliosphere between the termination shock and heliopause. To search for evidence of heliosheath absorption, we conduct a systematic inspection of stellar Ly-alpha lines reconstructed after correcting for ISM absorption (and heliospheric/astrospheric absorption, if present). Most of the stellar lines are well centered on the stellar radial velocity, as expected, but the three lines of sight with the most downwind orientations relative to the ISM flow (Chi1 Ori, HD 28205, and HD 28568) have significantly blueshifted Ly-alpha lines. Since it is in downwind directions where heliosheath absorption should be strongest, the blueshifts are almost certainly caused by previously undetected heliosheath absorption. We make an initial comparison between the heliosheath absorption and the predictions of a pair of heliospheric models. A model with a complex multi-component treatment of plasma within the heliosphere predicts less absorption than a model with a simple single-fluid treatment, which leads to better agreement with the data. Finally, we find that nonplanetary energetic neutral atom (ENA) fluxes measured by the ASPERA-3 instrument on board Mars Express, which have been interpreted as being from the heliosheath, are probably too high to be consistent with the relative lack of heliosheath absorption seen by HST. This would argue for a local interplanetary source for these ENAs instead of a heliosheath source.

  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.

    1998-12-14T23:59:59.000Z

    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. Detection of alpha radiation in a beta radiation field

    DOE Patents [OSTI]

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

    2001-01-01T23:59:59.000Z

    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.

  4. 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

    1994-01-10T23:59:59.000Z

    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.

  5. The Origin and Properties of X-ray-emitting Gas in the Halos of both Starburst and Normal Spiral Galaxies

    E-Print Network [OSTI]

    David K. Strickland

    2004-10-12T23:59:59.000Z

    I discuss the empirical properties of diffuse X-ray emitting gas in the halos of both nearby starburst galaxies and normal spiral galaxies, based on high resolution X-ray spectral imaging with the Chandra X-ray Observatory. Diffuse thermal X-ray emission can provide us with unique observational probes of outflow and accretion processes occurring in star-forming galaxies, and their interaction with the inter-galactic medium. I consider both the spatial distribution of the diffuse X-ray emission in and around edge-on starburst galaxies with superwinds (e.g. surface brightness profiles, distribution with respect to H-alpha and radio emission), and its spectral properties (e.g. thermal or non-thermal nature, abundance ratios, temperatures and soft and hard X-ray luminosities). These results are discussed in the context of current theoretical models of supernova-driven superwinds, and compared to the more limited data on extra-planar hot gas around edge-on normal galaxies.

  6. Degradation of Isotopic Lactate and Acetate

    E-Print Network [OSTI]

    Aronoff, S.

    2010-01-01T23:59:59.000Z

    prescribed, BaC03 from the degradation of Ba acetnte co~~above procedure by the degradation of sjnthetic radio-lacticNo. W-7405-Eng o -48 DEGRADATION OF ISOTOPIC LACTATE AND

  7. The Isotopic Abundances of Magnesium in Stars

    E-Print Network [OSTI]

    Pamela Gay; David L. Lambert

    1999-11-11T23:59:59.000Z

    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.

  8. 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 ...

  9. 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

  10. Predictions of Alpha Decay Half lives of Heavy and Superheavy Elements

    E-Print Network [OSTI]

    C. Samanta; P. Roy Chowdhury; D. N. Basu

    2007-05-28T23:59:59.000Z

    Theoretical estimates for the lifetimes of several isotopes of heavy elements with Z=102-120 are presented by calculating the quantum mechanical tunneling probability in a WKB framework and using microscopic nucleus-nucleus potential obtained by folding the densities of interacting nuclei with the DDM3Y effective nuclear interaction. The $\\alpha$-decay half lives calculated in this formalism using the experimental $Q$-values are in good agreement over a wide range of experimental data. Half lives are also calculated using $Q$-values extracted from two mass formulae. The Viola-Seaborg-Sobiczewski (VSS) estimates of $\\alpha$-decay half lives with the same $Q$-values are presented for comparison. The half life calculations are found to be quite sensitive to the choice of $Q$-values. Comparison with the experimental data delineates the inadequacies of older mass predictions in the domain of heavy and superheavy elements as compared to the newer one by Muntian-Hofmann-Patyk-Sobiczewski, and highlights necessity of a more accurate mass formula which can predict $Q$-values with even higher precision.

  11. Saturated and efficient blue phosphorescent organic light emitting devices with Lambertian angular emission

    E-Print Network [OSTI]

    Saturated and efficient blue phosphorescent organic light emitting devices with Lambertian angular a microcavity to optimize the color of a phosphorescent organic light emitting device OLED based on the-sky blue.1063/1.2742577 The development of a stable, efficient, and saturated blue remains an important goal for phosphorescent organic

  12. 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

  13. 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)

    2009-06-30T23:59:59.000Z

    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.

  14. 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

  15. Emitting gas regions in Mrk 493: An extensive Fe II line emission region

    E-Print Network [OSTI]

    L. C. Popovic; A. Smirnova; D. Ilic; A. Moiseev; J. Kovacevic; V. Afanasiev

    2007-01-24T23:59:59.000Z

    We performed 3D spectroscopic observations of Mrk 493 in order to investigate the Fe II emitting region and their possible connection with the Hydrogen emitting region. We found that there is a strong Fe II emission in an extensive region ~ 4" x 4" around Sy 1 nucleus. The Fe II line width indicates that these lines are originated in an intermediate line region.

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

    E-Print Network [OSTI]

    iPage | i Modeling Population Exposures to Pollutants Emitted from Natural Gas Cooking. LBNL4885E #12;Modeling Population Exposures to Pollutants Emitted from Natural Gas Cooking Burners distributions resulting from use of natural gas cooking appliances across households in California. The model

  17. 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

  18. Light extraction efficiency enhancement of InGaN quantum wells light-emitting diodes with

    E-Print Network [OSTI]

    Gilchrist, James F.

    Light extraction efficiency enhancement of InGaN quantum wells light-emitting diodes@lehigh.edu Abstract: Improvement of light extraction efficiency of InGaN light emitting diodes (LEDs) using microstructures on the light extraction efficiency of III-Nitride LEDs was studied. Depending on the size

  19. 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

  20. 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

  1. Semiconductor lasers with broad tunnel-coupled waveguides, emitting at a wavelength of 980 nm

    SciTech Connect (OSTI)

    Zvonkov, N B; Ershov, A V; Zvonkov, B N; Maksimov, G A; Uskova, E A [Scientific-Research Physicotechnical Institute at the Nizhnii Novgorod State University, Nizhnii Novgorod (Russian Federation); Akhlestina, S A [Research Insitute of Chemistry, N.I. Lobachevskii Nizhnii Novgorod State University, Nizhnii Novgorod (Russian Federation)

    1999-03-31T23:59:59.000Z

    InGaP/GaAs/InGaAs semiconductor lasers with broad tunnel-coupled waveguides were developed and investigated experimentally. Output radiation power of 5.2 - 5.8 W was obtained from an emitting region 100 {mu}m wide with a 36{sup 0} divergence of the emitted radiation in a plane perpendicular to the p - n junction. (lasers)

  2. GaN light-emitting diodes with Archimedean lattice photonic crystals Aurlien David,a

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    GaN light-emitting diodes with Archimedean lattice photonic crystals Aurélien David,a Tetsuo Fujii 2005; published online 16 February 2006 We study GaN-based light emitting diodes incorporating the semiconductor due to its index contrast with air.1­6 Recently, PhCs were used as out- coupling gratings in GaN

  3. Carbon isotope fractionation in autotrophic Chromatium

    E-Print Network [OSTI]

    Wong, William Wai-Lun

    1974-01-01T23:59:59.000Z

    CARSON ISOTOPE FRACTIONATION IN AUTOTPOPHIC CHROYATIUN A Thesis 'JILLIAJJ J JAI LJJN BONG Submitted to the Graduate College of Texas A&H University in partial fulfillment of the requirenent for the degree of PLASTER OF SCIENCE August 1974...) August 1974 ABSTRACT Carbon Isotope Fractionation in Autotrophic Chromatium (August 1974) blilliam Wai-Lun Wang, B. S. , Texas Lutheran College Co-Chairmen of Advisory Committee: Dr. Isilliam N. Sackett Dr. Chauncey P. . Benedict Bacterial cells...

  4. Mass Parameterizations and Predictions of Isotopic Observables

    E-Print Network [OSTI]

    S. R. Souza; P. Danielewicz; S. Das Gupta; R. Donangelo; W. A. Friedman; W. G. Lynch; W. P. Tan; M. B. Tsang

    2003-03-24T23:59:59.000Z

    We discuss the accuracy of mass models for extrapolating to very asymmetric nuclei and the impact of such extrapolations on the predictions of isotopic observables in multifragmentation. We obtain improved mass predictions by incorporating measured masses and extrapolating to unmeasured masses with a mass formula that includes surface symmetry and Coulomb terms. We find that using accurate masses has a significant impact on the predicted isotopic observables.

  5. Structure effects in the region of superheavy elements via the $\\alpha$-decay chain of $^{293}$118

    E-Print Network [OSTI]

    Gupta, Raj K; Kumar, Rajesh; Balasubramaniam, M; Scheid, W; 10.1088/0954-3899/28/11/310

    2011-01-01T23:59:59.000Z

    The $\\alpha$-decay chain of $^{293}$118, first proposed in the Berkeley cold fusion experiment $^{208}$Pb($^{86}$Kr,1n) and now retracted, is calculated by using the preformed cluster model (PCM) of one of us (RKG). Also, the possible branchings of $\\alpha$-particles to heavier cluster decays of all the parents in this chain are calculated for the first time. The calculated Q-values, penetrabilities and preformation factors for $\\alpha$-decays suggest that the $^{285}$114 nucleus with Z=114, N=171 is a magic nucleus, either due to the magicity of Z=114, or of N=172 or of both. The N=172 is proposed to be a magic number in certain relativistic mean-field calculations, but with Z=120. The calculated cluster decays point to new interesting possibilities of $^{14}$C decay of the $^{281}$112 parent, giving rise to a (reasonably) deformed Z=106, N=161, $^{267}$106 daughter (N=162 being now established as the deformed magic shell) or to a doubly magic $^{48}$Ca cluster emitted from any of the parent nucleus in the $...

  6. Determination of $\\alpha_{s}$ using Jet Rates at LEP with the OPAL detector

    E-Print Network [OSTI]

    Abbiendi, G; Åkesson, P F; Alexander, G; Anagnostou, G; Anderson, K J; Asai, S; Axen, D; Bailey, I; Barberio, E; Barillari, T; Barlow, R J; Batley, J Richard; Bechtle, P; Behnke, T; Bell, K W; Bell, P J; Bella, G; Bellerive, A; Benelli, G; Bethke, Siegfried; Biebel, O; Boeriu, O; Bock, P; Boutemeur, M; Braibant, S; Brown, R M; Burckhart, H J; Campana, S; Capiluppi, P; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Ciocca, C; Csilling, A; Cuffiani, M; Dado, S; de Roeck, A; De Wolf, E A; Desch, Klaus; Dienes, B; Donkers, M; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Etzion, E; Fabbri, F L; Ferrari, P; Fiedler, F; Fleck, I; Ford, M; Frey, A; Gagnon, P; Gary, J W; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Giunta, M; Goldberg, J; Gross, E; Grunhaus, Jacob; Gruwé, M; Günther, P O; Sen-Gupta, A; Hajdu, C; Hamann, M; Hanson, G G; Harel, A; Hauschild, M; Hawkes, C M; Hawkings, R; Hemingway, R J; Herten, G; Heuer, R D; Hill, J C; Horváth, D; Igo-Kemenes, P; Ishii, K; Jeremie, H; Jovanovic, P; Junk, T R; Kanzaki, J; Karlen, D; Kawagoe, K; Kawamoto, T; Keeler, R K; Kellogg, R G; Kennedy, B W; Kluth, S; Kobayashi, T; Kobel, M; Komamiya, S; Kramer, T; Krasznahorkay, A; Krieger, P; Von Krogh, J; Kühl, T; Kupper, M; Lafferty, G D; Landsman, H; Lanske, D; Lellouch, D; Letts, J; Levinson, L; Lillich, J; Lloyd, S L; Loebinger, F K; Lü, J; Ludwig, A; Ludwig, J; Mader, W; Marcellini, S; Martin, A J; Mashimo, T; Mättig, P; McKenna, J A; McPherson, R A; Meijers, F; Menges, W; Merritt, F S; Mes, H; Meyer, N; Michelini, A; Mihara, S; Mikenberg, G; Miller, D J; Mohr, W; Mori, T; Mutter, A; Nagai, K; Nakamura, I; Nanjo, H; Neal, H A; Nisius, R; O'Neale, S W; Oh, A; Oreglia, M J; Orito, S; Pahl, C; Pásztor, G; Pater, J R; Pilcher, J E; Pinfold, J L; Plane, D E; Pooth, O; Przybycien, M B; Quadt, A; Rabbertz, K; Rembser, C; Renkel, P; Roney, J M; Rossi, A M; Rozen, Y; Runge, K; Sachs, K; Saeki, T; Sarkisyan-Grinbaum, E; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schieck, J; Schörner-Sadenius, T; Schröder, M; Schumacher, M; Seuster, R; Shears, T G; Shen, B C; Sherwood, P; Skuja, A; Smith, A M; Sobie, R J; Söldner-Rembold, S; Spanó, F; Stahl, A; Strom, D; Ströhmer, R; Tarem, S; Tasevsky, M; Teuscher, R; Thomson, M A; Torrence, E; Toya, D; Tran, P; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Ujvári, B; Vollmer, C F; Vannerem, P; Vertesi, R; Verzocchi, M; Voss, H; Vossebeld, Joost Herman; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wilson, G W; Wilson, J A; Wolf, G; Wyatt, T R; Yamashita, S; Zer-Zion, D; Zivkovic, L

    2006-01-01T23:59:59.000Z

    Hadronic events produced in e+e- collisions by the LEP collider and recorded by the OPAL detector were used to form distributions based on the number of reconstructed jets. The data were collected between 1995 and 2000 and correspond to energies of 91 GeV, 130-136 GeV and 161-209 GeV. The jet rates were determined using four different jet-finding algorithms (Cone, JADE, Durham and Cambridge). The differential two-jet rate and the average jet rate with the Durham and Cambridge algorithms were used to measure alpha(s) in the LEP energy range by fitting an expression in which order alpah_2s calculations were matched to a NLLA prediction and fitted to the data. Combining the measurements at different centre-of-mass energies, the value of alpha_s (Mz) was determined to be alpha(s)(Mz)=0.1177+-0.0006(stat.)+-0.0012$(expt.)+-0.0010(had.)+-0.0032

  7. Ion desolvation as a mechanism for kinetic isotope fractionation in aqueous systems

    E-Print Network [OSTI]

    Hofmann, A.E.

    2014-01-01T23:59:59.000Z

    equilibrium light?isotope  enrichment is a key unknown in of light?isotope  enrichment  during  precipitation.  possible light? isotope enrichment from diffusion?limited 

  8. NATIONAL USES AND NEEDS FOR SEPARATED STABLE ISOTOPES IN PHYSICS, CHEMISTRY, AND GEOSCIENCE RESEARCH

    E-Print Network [OSTI]

    Zisman, M.S.

    2010-01-01T23:59:59.000Z

    of purchasing a low-enrichment isotope and having it furtherfour main areas: of isotopes, marginal enrichment and a highthe allowing isotope much interest enrichment into play, in

  9. Oxygen isotope fractionation in the vacuum ultraviolet photodissociation of carbon monoxide: Wavelength, pressure and temperature dependency.

    E-Print Network [OSTI]

    Chakraborty, Subrata

    2013-01-01T23:59:59.000Z

    Oxygen isotope fractionation in the vacuum ultravioletmeasurement of the associated oxygen isotopic composition ofwavelength dependency of the oxygen isotopic composition in

  10. Constraints on the ionizing flux emitted by T Tauri stars

    E-Print Network [OSTI]

    R. D. Alexander; C. J. Clarke; J. E. Pringle

    2005-01-06T23:59:59.000Z

    We present the results of an analysis of ultraviolet observations of T Tauri Stars (TTS). By analysing emission measures taken from the literature we derive rates of ionizing photons from the chromospheres of 5 classical TTS in the range ~10^41-10^44 photons/s, although these values are subject to large uncertainties. We propose that the HeII/CIV line ratio can be used as a reddening-independent indicator of the hardness of the ultraviolet spectrum emitted by TTS. By studying this line ratio in a much larger sample of objects we find evidence for an ionizing flux which does not decrease, and may even increase, as TTS evolve. This implies that a significant fraction of the ionizing flux from TTS is not powered by the accretion of disc material onto the central object, and we discuss the significance of this result and its implications for models of disc evolution. The presence of a significant ionizing flux in the later stages of circumstellar disc evolution provides an important new constraint on disc photoevaporation models.

  11. White Light Emitting Diode Development for General Illumination Applications

    SciTech Connect (OSTI)

    James Ibbetson

    2006-05-01T23:59:59.000Z

    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.

  12. Microchemical investigations of dust emitted by a lead smelter

    SciTech Connect (OSTI)

    Sobanska, S.; Ricq, N. [Ecole des Mines de Douai (France). Dept. Chimie et Environnement] [Ecole des Mines de Douai (France). Dept. Chimie et Environnement; [Univ. de Lille I, Villeneuve d`Ascq (France); Laboudigue, A.; Guillermo, R. [Ecole des Mines de Douai (France). Dept. Chimie et Environnement] [Ecole des Mines de Douai (France). Dept. Chimie et Environnement; Bremard, C.; Laureyns, J.; Merlin, J.C.; Wignacourt, J.P. [Univ. de Lille I, Villeneuve d`Ascq (France)] [Univ. de Lille I, Villeneuve d`Ascq (France)

    1999-05-01T23:59:59.000Z

    Dusts emitted by an important pyrometallurgical lead smelter have been sampled within the pipes of the grilling and furnace working units before and after the filtering systems, respectively. Particle size distribution, elementary analyses, and X-ray powder diffraction analysis indicate PbS, PbSO{sub 4}, PbSO{sub 4}{center_dot}PbO, Pb, ZnS small particles less than 5 {micro}m in size to contribute mainly to the current atmospheric pollution. Although at least 90% of dust are retained on the filters, the amounts of the respirable smaller particles are significantly larger in the current emission. The average chemical speciation was found to be analogous for the dust samples collected before and after the filters. The scanning electron microscopy associated with energy-dispersive X-ray analysis and Raman microspectrometry established the morphology and chemical composition at the level of individual particles. A lot of minor compounds were found as small heterogeneous individual particles in the heterogeneous particles of grilling dust. Among the homogeneous particles of furnace dust, amorphous C, {beta}-PbO, PbO-PbCl{sub 2}, FeO, CdS, CdSO{sub 4} were often detected as homogeneous mixtures with the major compounds within the particles.

  13. Producing a compound Nucleus via Inelastic Scattering: The 90Zr(alpha,alpha')90Zr* Case

    SciTech Connect (OSTI)

    Escher, J E; Dietrich, F S

    2008-05-23T23:59:59.000Z

    In a Surrogate reaction a compound nucleus is produced via a direct reaction (pickup, stripping, or inelastic scattering). For a proper application of the Surrogate approach it is necessary to predict the resulting angular momentum and parity distribution in the compound nucleus. A model for determining these distributions is developed for the case of inelastic alpha scattering off a spherical nucleus. The focus is on obtaining a first, simple description of the direct-reaction process that produces the compound nucleus and on providing the basis for a more complete treatment of the problem. The approximations employed in the present description are discussed and the extensions required for a more rigorous treatment of the problem are outlined. To illustrate the formalism, an application to {sup 90}Zr({alpha},{alpha}{prime}){sup 90}Zr* is presented.

  14. Carbonitride based phosphors and light emitting devices using the same

    DOE Patents [OSTI]

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

    2013-08-20T23:59:59.000Z

    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

  15. 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)

    2014-04-01T23:59:59.000Z

    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.

  16. Alpha decay chains from element 113

    E-Print Network [OSTI]

    P. Roy Chowdhury; D. N. Basu; C. Samanta

    2007-04-30T23:59:59.000Z

    Theoretical estimates of $\\alpha$-decay half lives of several nuclei in the decay from element 113 are presented. Calculations in a WKB framework using DDM3Y interaction and experimental Q-values are in good agreement with the experimental data. Half life calculations are found to be quite sensitive to the Q-values and angular momenta transfers. Calculated decay lifetime decreases, owing to more penetrability as well as thinner barrier, as Q-value increases. Deviations to this predominant behaviour observed in some recent experimental data may be attributed to non zero spin-parities in some cases.

  17. Electron shell and the alpha-decay

    E-Print Network [OSTI]

    Sergey Yu. Igashov; Yury M. Tchuvil'sky

    2012-12-03T23:59:59.000Z

    The ratio of the alpha-decay widths of a bare nucleus and the related atom is calculated. Both the change of the form and thus the penetrability of the potential barrier and the effect of reflection in the classically-allowed region appearing due to the electron shell are taken into account in the calculations of this ratio. The contribution of each of these two effects is of one and the same order of magnitude. For long-lived radioactive samples the values of the total effect turn out to be somewhat below 1 percent.

  18. 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)

    2014-05-02T23:59:59.000Z

    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.

  19. Alpha Renewable Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTriWildcat Place: Wayne,Energy Information Jump to:Alpha Energy Place:

  20. Tri Alpha Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit withTianlin Baxin Hydropower StationTown ofTownNote-BangladeshTri Alpha Energy

  1. Organic light emitting device architecture for reducing the number of organic materials

    DOE Patents [OSTI]

    D'Andrade, Brian (Westampton, NJ); Esler, James (Levittown, PA)

    2011-10-18T23:59:59.000Z

    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.

  2. H$\\alpha$ and EUV observations of a partial CME

    E-Print Network [OSTI]

    Christian, Damian J; Antolin, Patrick; Mathioudakis, Mihalis

    2015-01-01T23:59:59.000Z

    We have obtained H$\\alpha$ high spatial and time resolution observations of the upper solar chromosphere and supplemented these with multi-wavelength observations from the Solar Dynamic Observatory (SDO) and the {\\it Hinode} ExtremeUltraviolet Imaging Spectrometer (EIS). The H$\\alpha$ observations were conducted on 11 February 2012 with the Hydrogen-Alpha Rapid Dynamics Camera (HARDcam) instrument at the National Solar Observatory's Dunn Solar Telescope. Our H$\\alpha$ observations found large downflows of chromospheric material returning from coronal heights following a failed prominence eruption. We have detected several large condensations ("blobs") returning to the solar surface at velocities of $\\approx$200 km s$^{-1}$ in both H$\\alpha$ and several SDO AIA band passes. The average derived size of these "blobs" in H$\\alpha$ is 500 by 3000 km$^2$ in the directions perpendicular and parallel to the direction of travel, respectively. A comparison of our "blob" widths to those found from coronal rain, indicate...

  3. Design, construction, and operation of a laboratory scale reactor for the production of high-purity, isotopically enriched bulk silicon

    E-Print Network [OSTI]

    Ager III, J.W.; Beeman, J.W.; Hansen, W.L.; Haller, E.E.

    2004-01-01T23:59:59.000Z

    Russia. The stated isotope enrichments are summarized inenrichments >99% have been achieved for each isotope and

  4. Lyman alpha Absorption Systems and the Intergalactic Medium

    E-Print Network [OSTI]

    George Efstathiou; Joop Schaye; Tom Theuns

    2000-04-10T23:59:59.000Z

    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.

  5. 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

  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. Journal of Crystal Growth 298 (2007) 272275 Dislocation analysis in homoepitaxial GaInN/GaN light emitting

    E-Print Network [OSTI]

    Wetzel, Christian M.

    2007-01-01T23:59:59.000Z

    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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. Journal of Light Emitting Diodes Vol 2 N0 1, April 2010 1 Abstract--Semiconductor nanocrystal quantum dots (NQD)

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    Journal of Light Emitting Diodes Vol 2 N0 1, April 2010 1 Abstract-- Semiconductor nanocrystal convertors integrated on light-emitting diodes (LEDs). The use of nonradiative energy transfer, also known-LEDs for lighting applications. Index Terms-- Förster resonance energy transfer, light emitting diode, nanocrystal

  16. Interface electronic structures of organic light-emitting diodes with WO3 interlayer: A study by photoelectron spectroscopy

    E-Print Network [OSTI]

    Kim, Sehun

    Interface electronic structures of organic light-emitting diodes with WO3 interlayer: A study injec- tion and transport layers in an organic light-emitting diode (OLED) structure has been studied B.V. All rights reserved. 1. Introduction OLEDs (organic light-emitting diodes) are display de

  17. Surface Plasmon Enhanced Phosphorescent Organic Light Emitting Diodes

    SciTech Connect (OSTI)

    Guillermo Bazan; Alexander Mikhailovsky

    2008-08-01T23:59:59.000Z

    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.

  18. alpha 1-adrenoceptor antagonist: Topics by E-print Network

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

    present review provides an update on alphas measurements from the past year. W. J. Stirling 1997-09-23 5 Antagonistic competition moderates virulence in Bacillus thuringiensis...

  19. alpha spectrometry measurement: Topics by E-print Network

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

    Carlo code, known as AASI, is developed for simulating energy spectra in alpha spectrometry. The code documented here is a comprehensive package where all the major processes...

  20. alpha spectrometry 232u: Topics by E-print Network

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

    the source. Simulations and measurements highlight the importance of coincidences in high-resolution alpha spectrometry. To show the validity of the simulated results,...