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Sample records for nu6 nu7 nu13

  1. Dynamical transport of asteroid fragments from the nu6 resonance

    CERN Document Server

    Ito, T; Ito, Takashi; Malhotra, Renu

    2006-01-01

    A large disruption in the main asteroid belt can cause a large flux, an "asteroid shower", on the terrestrial planets. We quantitatively examine the hypothesis that such an event was the cause of the lunar late heavy bombardment (LHB). We performed numerical integrations of about 20000 test particles starting in the vicinity of the nu6 secular resonance in the main asteroid belt. The purpose of these integrations is to calculate, for each of the terrestrial planets, the collision probability of asteroids coming from an asteroid break-up event in the inner part of the main belt. Compared with previous studies, we simulate nearly two orders of magnitude larger number of particles, and we include the orbital effects of the eight planets, Mercury to Neptune. We also examined in detail the orbital evolution of asteroid fragments once they enter the Earth's activity sphere, including the effect of the Earth-Moon orbit. We obtained the collision probability, the distributions of impact velocities, impact positions, ...

  2. Analysis of the Coriolis Interaction between nu(6) and nu(8) Bands of HCOOH.

    Science.gov (United States)

    Tan; Goh; Ong; Teo

    2000-08-01

    The Fourier transform infrared (FTIR) spectrum of the nu(6) band of formic acid (HCOOH) has been recorded with a resolution of 0.0024 cm(-1) in the spectral range 1050-1160 cm(-1). The nu(6) band was found to be strongly perturbed by the nearby nu(8) band centered at about 1033.5 cm(-1). Using a Watson's A-reduced Hamiltonian in the I(r) representation, and with the inclusion of a-type Coriolis coupling constant, a simultaneous fit of nu(6) and nu(8) was performed. A total of 2485 infrared transitions including about 700 perturbed transitions of nu(6) and 19 transitions of nu(8) was fitted with an rms uncertainty of 0.0006 cm(-1). Accurate rovibrational constants up to sextic order for both nu(6) and nu(8) were obtained. The nu(6) band was analyzed to be a type AB hybrid with a band center at 1104.852109 +/- 0.000050 cm(-1). The band center for nu(8) was found to be 1033.4647 +/- 0.0021 cm(-1). Copyright 2000 Academic Press.

  3. Absolute Line Intensities for the nu6 Band of H2O2.

    Science.gov (United States)

    Klee; Winnewisser; Perrin; Flaud

    1999-05-01

    The purpose of this work was to obtain reliable absolute intensities for the nu6 band of H2O2. It was undertaken because strong discrepancies exist between the different nu6 band intensities which are presently available in the literature (A. Perrin, A. Valentin, J.-M. Flaud, C. Camy-Peyret, L. Schriver, A. Schriver, and P. Arcas, J. Mol. Spectrosc. 1995. 171, 358), (R. May, J. Quant. Radiat. Transfer 1991. 45, 267), and (R. L. Sams, personal communication). The method which was chosen in the present work was to measure simultaneously the far-infrared absorptions and the nu6 absorptions of H2O2. Consequently, Fourier transform spectra of H2O2 were recorded at Giessen in a spectral range (370-1270 cm-1) which covers both the R branch of the torsion-rotation band and the P branch of the nu6 band which appear at low and high wavenumbers, respectively. From the low wavenumber data, the partial pressure of H2O2 present in the cell during the recording of the spectra was determined by calibrating the observed absorptions in the torsion-rotation band with intensities computed using the permanent H2O2 dipole moment measured by Stark effect (A. Perrin, J.-M. Flaud, C. Camy-Peyret, R. Schermaul, M. Winnewisser, J.-Y. Mandin, V. Dana, M. Badaoui, and J. Koput, J. Mol. Spectrosc. 1996. 176, 287-296) and [E. A. Cohen and H. M. Pickett, J. Mol. Spectrosc. 1981. 87, 582-583). In the high frequency range, this value of the partial pressure of H2O2 was used to measure absolute line intensities in the nu6 band. Finally, the line intensities in the nu6 band were fitted using the theoretical methods described in detail in our previous works. Using these new results on line intensities together with the line position parameters that we obtained previously, a new synthetic spectra of the nu6 band was generated, leading to a total band intensity of 0.185 x 10(-16) cm-1/(molecule.cm-2) at 296 K. It has to be pointed out that the new line intensities agree to within the experimental

  4. The Coriolis Interaction between the nu(9) and nu(7) Fundamental Bands of Methylene Fluoride.

    Science.gov (United States)

    Goh; Tan; Ong; Teo

    2000-06-01

    The infrared spectrum of the nu(7) and nu(9) bands of methylene fluoride-d(2) (CD(2)F(2)) has been recorded with an unapodized resolution of 0.0024 cm(-1) in the frequency range of 940-1030 cm(-1) using the Fourier transform technique. A weak b-type Coriolis interaction term was found to couple these two vibrational states with band centers about 42 cm(-1) apart. By fitting a total of 1031 infrared transitions of both nu(7) and nu(9) with a standard deviation of 0.0011 cm(-1) using a Watson's A-reduced Hamiltonian in the I(r) representation with the inclusion of a b-type Coriolis resonance term, two sets of rovibrational constants for nu(7) = 1 and nu(9) = 1 states up to sextic order were derived. The nu(7) band is C type, while the nu(9) band is A type with band centers at 961.8958 +/- 0.0005 and 1003.7421 +/- 0.0001 cm(-1), respectively. Copyright 2000 Academic Press.

  5. Analysis of the Infrared Spectra of the Fundamentals nu3 and nu6 of 12CD3I and 13CD3I

    Science.gov (United States)

    Koivusaari

    1997-09-01

    The high-resolution infrared spectra of the lowest fundamental bands nu3 and nu6 of 12CD3I and 13CD3I have been measured using a Fourier transform spectrometer. The bands are analyzed on one hand by taking into account the Coriolis resonance nu3/nu6 and on the other hand without this Coriolis effect. The molecular constants obtained for the two vibration modes are introduced and a discussion of the influence of the Coriolis interaction to the parameter set is shortly outlined. Copyright 1997 Academic Press. Copyright 1997Academic Press

  6. High-Resolution Fourier Transform Infrared Spectroscopy of Vinyl Alcohol: Rotational Analysis of the nu(13) CH(2) Wagging Fundamental at 817 cm(-1).

    Science.gov (United States)

    Joo; Merer; Clouthier

    1999-09-01

    The first high-resolution infrared spectra of the unstable molecule vinyl alcohol are reported. The spectra have been obtained using a new precursor, 2-chloroethanol, which when pyrolyzed at 1050 degrees C gives strong infrared spectra of vinyl alcohol free of interfering hydrocarbon absorption bands. In this work, we have analyzed the strong nu(13) fundamental at 817 cm(-1) and substantially improved the ground state rotational constants by a simultaneous fitting of previous microwave data and a large number of infrared combination differences. The 13(1) upper state was found to be perturbed by the 15(2) "dark" state at 775.7 cm(-1), and a complete analysis of the perturbed rotational structure has been achieved using an interacting two-state model. Further small perturbations at high K(a) and J have been identified as interactions with the nu(10) and nu(12) fundamentals at 948 and 960 cm(-1), respectively. Copyright 1999 Academic Press.

  7. IR spectrum of CH3CN-BF3 in solid neon: matrix effects on the structure of a Lewis acid-base complex.

    Science.gov (United States)

    Eigner, Audrey A; Rohde, John A; Knutson, Christopher C; Phillips, James A

    2007-02-15

    We have observed several IR bands of CH3CN-BF3 in neon and nitrogen matrices. For the 11B isotopomer in neon matrices, we observed the BF3 symmetric deformation band (nu7) as a doublet at 600 and 603 cm(-1), the BF3 symmetric stretching band (nu6) as a doublet at 833 and 838 cm(-1), the BF3 asymmetric stretching mode (nu13) at 1281 cm(-1) (partially obscured), and the C-N stretching mode (nu2) as a doublet at 2352 and 2356 cm(-1). The nitrogen matrix data are largely consistent with those reported recently, though we do propose a refinement of one band assignment. Comparisons of the frequencies of a few key, structurally sensitive vibrational modes either observed in various condensed-phase environments or calculated for two minimum-energy gas-phase structures indicate that inert matrix media significantly alter the structural properties of CH3CN-BF3. Specifically, the B-N dative bond compresses relative to the gas phase and other concomitant changes occur as well. Furthermore, the frequency shifts depict structural changes that occur across the various matrix hosts in a manner that largely parallels the degree of stabilization offered by these inert media.

  8. Psychometric function for NU-6 word recognition in noise: effects of first language and dominant language.

    Science.gov (United States)

    Shi, Lu-Feng; Zaki, Nancy A

    2014-01-01

    The present study attempted to establish psychometric function in individuals whose first language is not English. Psychometric function was obtained for one of the most commonly used clinical tests, the Northwestern University Auditory Test No. 6 (Tillman & Carhart 1966), so that findings could be directly applied to everyday clinical practice. Five groups of 14 normal-hearing, adult listeners differing in their first language and dominant language (English monolinguals, English- and Arabic-dominant Arabic-English bilinguals, and English- and Russian-dominant Russian-English bilinguals) participated. Both forms of the Northwestern University Auditory Test No. 6 test (8 lists of 50 monosyllabic English words) were presented. The lists were randomly assigned to eight signal-to-noise ratios (-3 to 18 dB in 3 dB steps). Listeners responded verbally and in writing. Psychometric functions were derived via logistic regression and described by two parameters: the 50% correct performance level (θ) and the slope (k). Both English-dominant bilingual groups obtained psychometric functions comparable with monolinguals. The θ and k of the functions for these three groups of participants were consistent with the literature. Compared with these three groups, non-English-dominant bilinguals' functions grew significantly more gradually (i.e., a significantly higher θ and a significantly lower k). No differences in either θ or k were found between bilinguals with the same dominant language but different first languages. Bilinguals reporting themselves to be dominant in English generate monolingual-like psychometric functions. By contrast, a different set of psychometric properties describes the function of bilinguals dominant in their first language. Because first language did not appear to be a significant factor in determining bilinguals' functions, it is concluded that English learning history and English proficiency are more important variables than first language for clinicians to consider when administering English word-recognition tests to their bilingual clients. When working with bilingual clients who are dominant in their first language, clinicians are advised to refer to the normative data reported here specifically for these individuals.

  9. A combined IRAM and Herschel/HIFI study of cyano(di)acetylene in Orion KL: tentative detection of DC3N

    CERN Document Server

    Esplugues, G B; Viti, S; Goicoechea, J R; Tercero, B; Marcelino, N; Palau, Aina; Bell, T A; Bergin, E A; Crockett, N R; Wang, S

    2013-01-01

    We present a study of cyanoacetylene (HC3N) and cyanodiacetylene (HC5N) in Orion KL, through observations from two line surveys performed with the IRAM 30m telescope and the HIFI instrument on board the Herschel telescope. The frequency ranges covered are 80-280 GHz and 480-1906 GHz. We model the observed lines of HC3N, HC5N, their isotopologues (including DC3N), and vibrational modes, using a non-LTE radiative transfer code. To investigate the chemical origin of HC3N and DC3N in Orion KL, we use a time-dependent chemical model. We detect 40 lines of the ground state of HC3N and 68 lines of its 13C isotopologues. We also detect 297 lines of six vibrational modes of this molecule (nu_7, 2nu_7, 3nu_7, nu_6, nu_5, and nu_6+nu_7) and 35 rotational lines of the ground state of HC5N. We report the first tentative detection of DC3N in a giant molecular cloud with a DC3N/HC3N abundance ratio of 0.015. We provide column densities and isotopic and molecular abundances. We also perform a 2x2" map around Orion IRc2 and w...

  10. High Resolution Infrared Spectroscopy of Allene -D4.

    Science.gov (United States)

    Rousan, Khetam Ibrahim Khasawinah

    Two parallel bands of allene-d(,4), (nu)(,6) (occurring at 1920.2289 cm('-1)) and (nu)(,5) (occurring at 2228.4133 cm('-1)), and the perpendicular band, (nu)(,8) (occurring at 2321.2484 cm('-1)), were recorded by using two spectrometers under high resolution. The combination band, (nu)(,2) + (nu)(,7), was measured also; the band origin is located at 2276.0053 cm('-1), rather distant from the previously reported one at 2267.0 cm('-1). Initially, by using the 4.5 m grating spectrometer, deconvolution of the spectra achieved a resolution of (TURN)0.007 cm('-1). Although the resolution was high, a detailed analysis of the K structure could not be obtained. Other measurements were carried out by using a BOMEM Fourier transform spectrometer. Deconvolution of the spectra achieved a resolution of (TURN)0.002 cm(' -1). This made it possible to resolve and analyze these bands in detail. Successful ground state and upper state analyses were completed from this data. Combining all the three bands together, a ground state analysis has resulted in better values of. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI). than the previously published works on the same molecule by others. A set of accurate spectroscopic constants was obtained for each band. The spectrum of the (nu)(,8) band was analyzed in detail, including the perturbations. The perturbed states for (nu)(,8) were assigned as 2(nu)(,9) + (nu)(,10), (nu)(,2) + (nu)(,9) + (nu)(,11) and 2(nu)(,3) + (nu)(,4), and the spectroscopic constants for those perturbed states were calculated.

  11. The Coriolis-Coupled States v7 = 1 and v9 = 1 of trans-HCOOD and trans-DCOOD.

    Science.gov (United States)

    Baskakov; Bürger; Jerzembeck

    1999-01-01

    The Fourier transform gas-phase infrared spectra of the two lowest Coriolis-perturbed nu7 and nu9 bands of deuterated formic acid HCOOD and DCOOD have been measured with a resolution of ca. 0.003 cm-1. Combined analysis of the assigned IR transitions and all the available rotational data have allowed the determination of the band centers, rotational and centrifugal distortion parameters, and Coriolis coupling terms. Standard deviations of the IR transitions are 0.000246 cm-1 for HCOOD and 0.000209 cm-1 for DCOOD. Determined band centers are nu0(nu7) = 558.2723 cm-1, nu0(nu9) = 508.1321 cm-1 for HCOOD and nu0(nu7) = 554.4397 cm-1, nu0(nu9) = 492.2254 cm-1 for DCOOD. Copyright 1999 Academic Press.

  12. Application of a Discrete Nonlinear Spectral Model to Ideal Cases of Wind Wave Generation.

    Science.gov (United States)

    1982-04-01

    ER-4t IETURN END A28 UtIROUT1 4E PLOTV SUBR)UT14E P.JTV(XYNPTSISYMNJUTIER) RourINE TO PLOT VECTO1 Y AGA14ST VECTOR X )IME.NSI)4 Ki 1) ,YQ) INTEGER...TITLE C NF - NUMBER 3F FREOUENCIES C IGR).X - SUMA =R OF GRID POINTS IN X DIRECTION C IGR9( - NU13:R OF GRID POINTS IN Y DIRECTION C NPTSK - NJ’I3tR

  13. The Coriolis-Coupled States v(6) = 1 and v(8) = 1 of DCOOH.

    Science.gov (United States)

    Baskakov; Alanko; Koivusaari

    1999-11-01

    The Fourier transform gas-phase infrared spectra of the Coriolis-perturbed nu(6) and nu(8) bands of deuterated formic acid DCOOH were measured with a resolution of ca. 0.003 cm(-1). Combined analysis of the 8977 IR transitions and all the available rotational data (from literature) in the ground state, as well as in the excited vibrational states v(6) = 1 and v(8) = 1 was carried out. The Coriolis coupling terms were determined and improved sets of rotational and centrifugal distortion parameters for the ground and excited vibrational states were obtained. The determined band centers are nu(0) (nu(8)) = 873.385046(12) cm(-1) and nu(0) (nu(6)) = 970.8889551(46) cm(-1). Copyright 1999 Academic Press.

  14. CT-Derived Estimation of Cochlear Morphology and Electrode Array Position in Relation to Word Recognition in Nucleus-22 Recipients

    OpenAIRE

    Skinner, Margaret W.; Ketten, Darlene R.; Holden, Laura K.; Harding, Gary W.; Smith, Peter G.; Gates, George A.; Neely, J. Gail; Kletzker, G. Robert; Brunsden, Barry; Blocker, Barbara

    2002-01-01

    This study extended the findings of Ketten et al. [Ann. Otol. Rhinol. Laryngol. Suppl. 175:1–16 (1998)] by estimating the three-dimensional (3D) cochlear lengths, electrode array intracochlear insertion depths, and characteristic frequency ranges for 13 more Nucleus-22 implant recipients based on in vivo computed tomography (CT) scans. Array insertion depths were correlated with NU-6 word scores (obtained one year after SPEAK strategy use) by these patients and the 13 who used the SPEAK strat...

  15. Effective Field Theory of Fractional Quantized Hall Nematics

    Energy Technology Data Exchange (ETDEWEB)

    Mulligan, Michael; /MIT, LNS; Nayak, Chetan; /Station Q, UCSB; Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC

    2012-06-06

    We present a Landau-Ginzburg theory for a fractional quantized Hall nematic state and the transition to it from an isotropic fractional quantum Hall state. This justifies Lifshitz-Chern-Simons theory - which is shown to be its dual - on a more microscopic basis and enables us to compute a ground state wave function in the symmetry-broken phase. In such a state of matter, the Hall resistance remains quantized while the longitudinal DC resistivity due to thermally-excited quasiparticles is anisotropic. We interpret recent experiments at Landau level filling factor {nu} = 7/3 in terms of our theory.

  16. Word Frequency Analysis. MOS: 05C. Skill Levels 1 & 2

    Science.gov (United States)

    1981-05-01

    34- It FC F 4 Ijrv(1pE 11 ITrjt p~R 31 ,lrsr p 31 III.F IpIP 1 IFPICALAUTh1EFI1ICATIO4 NW r. 6 r nm a nu 6 not-?633GHC 3 DA-?633A/GRC 2 mA 33A/GKC...CLIPEI? 24 ELrCTRICAL -P! VVALL;ATICl-----------24 FULLY -24 21r3C3C . . .24 KFFP 7. - .74 10CIJ4T 24 PE R? SF83 24 SCALE 2’ 1 -1VAT 1ICN 74 SIM0*3 2

  17. The positions of secular resonance surfaces. [for major planet orbits

    Science.gov (United States)

    Williams, J. G.; Faulkner, J.

    1981-01-01

    The surfaces for the three strongest secular resonances have been located as a function of proper semimajor axis, eccentricity, and inclination for semimajor axes between 1.25 and 3.5 AU. The results are presented graphically. The nu5 resonance only occurs at high inclinations (approximately greater than 23 deg). The nu6 resonance passes through both the main belt and Mars-crossing space. The nu16 resonance starts near the inner edge of the belt and, at low inclinations at least, folds around a portion of the Mars-crossing space until it runs nearly parallel with the earth-crossing boundary.

  18. Low temperature vibrational spectroscopy. I. Hexachlorotellurates

    DEFF Research Database (Denmark)

    Berg, Rolf W.; Poulsen, Finn Willy; Bjerrum, Niels

    1977-01-01

    frequency lattice modes were observed and interpreted in terms of a phase transition near 165 K, similar to transitions in other K2[MX6] salts. The cubic tetramethylammonium hexachlorotellurate salt undergoes a phase transition of supposed first order at a temperature near 110 K, corresponding...... to transitions known in analogous uranium and tin compounds. Possible reasons for the transitions are discussed. In the low temperature phases the nu4 and nu6 bendings of [TeCl6]2− have been identified with bands near ~130 and ~110 cm−1. No evidence seemed to favor any stereochemical distortion due to the lone...

  19. Acoustic power absorption and enhancement generated by slow and fast MHD waves

    CERN Document Server

    Simoniello, R; Garcia, R A; Salabert, D; Jimenez, A; Elsworth, Y; Schunker, H

    2010-01-01

    We used long duration, high quality, unresolved (Sun-as-a star) observations collected by the ground based network BiSON and by the instruments GOLF and VIRGO on board the ESA/NASA SOHO satellite to search for solar-cycle-related changes in mode characteristics in velocity and continuum intensity for the frequency range between 2.5mHz < nu < 6.8mHz. Over the ascending phase of solar cycle 23 we found a suppression in the p-mode amplitudes both in the velocity and intensity data between 2.5mHz nu < 6.8mHz, we found an enhancement in ...

  20. Towards an Understanding of the Mid-Infrared Surface Brightness of Normal Galaxies

    CERN Document Server

    Dale, D A; Silbermann, N A; Contursi, A; Malhotra, S; Rubin, R H; Dale, Daniel A.; Helou, George; Silbermann, Nancy A.; Contursi, Alessandra; Malhotra, Sangeeta; Rubin, Robert H.

    1999-01-01

    We report a mid-infrared color and surface brightness analysis of IC 10, NGC 1313, and NGC 6946, three of the nearby galaxies studied under the Infrared Space Observatory Key Project on Normal Galaxies. Images with < 9 arcsecond (170 pc) resolution of these nearly face-on, late-type galaxies were obtained using the LW2 (6.75 mu) and LW3 (15 mu) ISOCAM filters. Though their global I_nu(6.75 mu)/I_nu(15 mu) flux ratios are similar and typical of normal galaxies, they show distinct trends of this color ratio with mid-infrared surface brightness. We find that I_nu(6.75 mu)/I_nu(15 mu) ~< 1 only occurs for regions of intense heating activity where the continuum rises at 15 micron and where PAH destruction can play an important role. The shape of the color-surface brightness trend also appears to depend, to the second-order, on the hardness of the ionizing radiation. We discuss these findings in the context of a two-component model for the phases of the interstellar medium and suggest that star formation inte...

  1. Measurement of Ds+ to mu+ nu and the Decay constant f_Ds

    CERN Document Server

    Artuso, M; Butt, J; Li, J; Menaa, N; Mountain, R; Nisar, S; Randrianarivony, K; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Asner, D M; Edwards, K W; Briere, R A; Brock, I; Chen, J; Ferguson, T; Tatishvili, G T; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Onyisi, P U E; Patterson, J R; Peterson, D; Pivarski, J; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Weinberger, M; Athar, S B; Patel, R; Potlia, V; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; White, E J; Wiss, J; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Smith, A; Zweber, P; Dobbs, S; Metreveli, Z V; Seth, K K; Tomaradze, A G; Ernst, J; Severini, H; Dytman, S A; Love, W; Savinov, V; Aquines, O; Li, Z; López, A; Mehrabyan, S S; Méndez, H; Ramírez, J; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Coan, T E; Gao, Y S; Liu, F

    2007-01-01

    We examine e+e- to Ds- Ds*+ or Ds-* Ds+ collisions at 4170 MeV using the CLEO-c detector in order to measure the decay constant f_Ds+. We use the Ds+ to ell+ nu channel, where the ell+ designates either a mu+ or a tau+. Analyzing both modes simultaneously, we determine B(D_s^+ to mu+ nu)= (0.657 +- 0.090 +- 0.028)%, B(D_s^+ to tau+ nu)= (7.1 +- 1.4 +- 0.3)%, and extract f_Ds+ = 282 +- 16 +- 7 MeV. Combining with our previous determination of B(D+ to mu+ nu), we find that the ratio f_Ds+/f_D+ = 1.27 +- 0.12 +- 0.03. (All new results here are preliminary.) We compare with current theoretical estimates.

  2. Electronic relaxations of radiative defects of the anion sublattice in cesium bromide crystals and exoemission of electrons

    CERN Document Server

    Galyij, P V

    2002-01-01

    The paper presents the results of investigations of thermostimulated exoelectron emission (TSEE) from CsBr crystal, excited by moderate doses (D <= 10 sup 4 Gy) of ultraviolet (h nu <= 7 eV) that selectively creates anion excitons and radiative defects in the anion sublattice. Having used the previously established connection between thermoactivated processes such as thermostimulated exoemission, electroconductivity, and luminescence in the irradiated crystal lattice, the concentrations of exoemission-active centers (EAC) and kinetics parameters of TSEE are calculated. The EAC concentration calculated on a base of the bulk, thermoactivated-recombinational, and band-gap Auger-like exoemission mechanisms, are in satisfactory agreement with the concentration of electron color centers in the irradiated crystals.

  3. Hvor mange kan vi byde velkommen til Verden?

    DEFF Research Database (Denmark)

    Nørgaard, Jørgen

    2011-01-01

    Verdens befolkningstal på nu 7 milliarder er naturligvis en af de væsentlige årsager til de menneskeskabte miljøproblemer, vi står overfor. Alligevel har det længe været et tabu at inddrage befolkningsudviklingen i miljødebatten. Men hvis den globale miljøbelastning skal minimeres betragteligt, s...... gør befolkningsreduktion til en af de billigste og mest nænsomme veje til redning af klimaet og miljøet. Det kræver dog at miljøorganisationerne tør tale dette afgørende emne....

  4. Post-Newtonian approximation of the Einstein-Cartan-Sciama-Kibble theory

    Energy Technology Data Exchange (ETDEWEB)

    Castagnino, M.; Levinas, M.L.; Umerez, N.

    1985-07-01

    The post-Newtonian approximation is applied to determine the exterior trajectories of test particles for the Einstein-Cartan-Sciama-Kibble generalization of general relativity, in which torsion due to matter spin does not propagate in the vacuum. The ideal-spinning-fluid model of Hehl et al. (1976) is employed, and the torsion corrections to the fourth-order potential psi are estimated. A significant reduction (relative to earlier theories) in the mass density required of an astronomical object for matter spin to be detectable is obtained, permitting experimental detection in stars with structures known to order v-bar and verification of the theory (via the acceleration equation) in objects with structures known to the second order in sigma-bar to the mu nu. 7 references.

  5. Arginine bi-directional translocation and breakdown into ornithine along the arbuscular mycorrhizal mycelium

    Institute of Scientific and Technical Information of China (English)

    JIN HaiRu

    2009-01-01

    Bi-directional translocatlon and degradation of Arginine (Arg) along the arbuscular mycorrhizal (AM) fungal mycellum were testified through 15N and/or 13C isotopic labeling. In vitro mycorrhizas of Glomus intraradices and Ri T-DNA-transformed carrot roots were grown in dual compartment Petri dishes. [15N-and/or13C]Arg was supplied to either the fungal compartment or the mycorrhizal compartment or separate dishes containing the uncolonized roots. The levels and labeling of free amino acids (AAs) in the mycorrhizal roots and in the extraradical mycelia(ERM) were measured by gas chromatogra-phy/mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The ERM of AM fungi exposed in either NH4+ or urea as sole external nitrogen source had much higher 15N enrichment of Arg, compared with those In nitrate or exogenous Arg; however, glycerol supplied as an external car-bon source to the ERM had no significant effect on the level of Arg in the ERM. Meanwhile, Arg bio-synthesized In the ERM could be translocated intact to the mycorrhizal roots and thereby the level of Arg in the mycorrhizal roots increased to about 20% after culture of ERM in 4 mmol/L NH4+ for 6 weeks.Also Arg was found to be bi-directionally transported along the AM fungal mycelium through [U-13C]Arg labeling either In the mycorrhizal compartment or in the fungal compartment. Once Arg was translo-cated to the potential N-limited sites, it would be further degraded into ornithine (Orn) and urea since either [U-13C] or [U-15N/U-13C]Orn was apparently shown up in the mycorrhizal root tissues when [U-13C] or [U-15N/U-13C]Arg was labeled In the fungal compartment, respectively. Evidently Orn formation indi-cated the ongoing activities of Arg translocation and degradation through the urea cycle in AM fungal mycelium.

  6. Arginine bi-directional translocation and breakdown into ornithine along the arbuscular mycorrhizal mycelium

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Bi-directional translocation and degradation of Arginine (Arg) along the arbuscular mycorrhizal (AM) fungal mycelium were testified through 15N and/or 13C isotopic labeling. In vitro mycorrhizas of Glomus intraradices and Ri T-DNA-transformed carrot roots were grown in dual compartment Petri dishes. [15N- and/or13C]Arg was supplied to either the fungal compartment or the mycorrhizal compartment or separate dishes containing the uncolonized roots. The levels and labeling of free amino acids (AAs) in the mycorrhizal roots and in the extraradical mycelia(ERM) were measured by gas chromatogra- phy/mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The ERM of AM fungi exposed in either NH4+ or urea as sole external nitrogen source had much higher 15N enrichment of Arg, compared with those in nitrate or exogenous Arg; however, glycerol supplied as an external car- bon source to the ERM had no significant effect on the level of Arg in the ERM. Meanwhile, Arg bio- synthesized in the ERM could be translocated intact to the mycorrhizal roots and thereby the level of Arg in the mycorrhizal roots increased to about 20% after culture of ERM in 4 mmol/L NH4+ for 6 weeks. Also Arg was found to be bi-directionally transported along the AM fungal mycelium through [U-13C]Arg labeling either in the mycorrhizal compartment or in the fungal compartment. Once Arg was translo- cated to the potential N-limited sites, it would be further degraded into ornithine (Orn) and urea since either [U-13C] or [U-15N/U-13C]Orn was apparently shown up in the mycorrhizal root tissues when [U-13C] or [U-15N/U-13C]Arg was labeled in the fungal compartment, respectively. Evidently Orn formation indi- cated the ongoing activities of Arg translocation and degradation through the urea cycle in AM fungal mycelium.

  7. The X-Ray to Mid-Infrared Relation of AGN at High Luminosity

    CERN Document Server

    Stern, Daniel

    2015-01-01

    The X-ray and mid-IR emission from active galactic nuclei (AGN) are strongly correlated. However, while various published parameterizations of this correlation are consistent with the low-redshift, local Seyfert galaxy population, extrapolations of these relations to high luminosity differ by an order of magnitude at nuL(nu)(6um) = 1e47 erg/s. Using data from the Wide-field Infrared Survey Explorer, we determine the mid-IR luminosities of the most luminous quasars from the Sloan Digital Sky Survey and present a revised formulation of the X-ray to mid-IR relation of AGN which is appropriate from the Seyfert regime to the powerful quasar regime.

  8. Evidence from Helioradiology of an Inner Tachocline in the Sun

    Science.gov (United States)

    Sturrock, P. A.; Bertello, L.; Fischbach, E.; Jenkins, J. H.

    2011-12-01

    One can make a good case that the Rieger and related solar oscillations may be understood as r-mode oscillations. The frequencies of these oscillations fit the formula 2*m*nu/(l*(l+1)), where l and m (two of the three spherical harmonic indices) take the values m = 1, l = 2,3,4,..., (the third index n does not affect the mode frequency), and the sidereal rotation frequency nu = 13.7 year-1. This value of the rotation frequency indicates that these oscillations occur in the tachocline, which separates the radiative zone from the convection zone. There is now strong evidence that beta decay rates are not constant, and there is a persuasive case that the Sun is responsible for variations in these rates. This new source of solar observational data, for which we propose the name "helioradiology," yields evidence that the solar core rotates more slowly than the radiative zone. This raises the possibility that there is a second, "inner," tachocline that separates the core from the radiative zone. This possibility in turn suggests that there may be a second group of "Rieger-like" oscillations that have their origin in this inner tachocline. We present evidence for such oscillations, derived from helioradiology data and also from the long-term diameter measurements acquired at the Mount Wilson Observatory.

  9. Darling-Dennison resonance and Coriolis coupling in the bending overtones of the A 1A(u) state of acetylene, C2H2.

    Science.gov (United States)

    Merer, Anthony J; Yamakita, Nami; Tsuchiya, Soji; Steeves, Adam H; Bechtel, Hans A; Field, Robert W

    2008-08-01

    Rotational analyses have been carried out for the overtones of the nu(4) (torsion) and nu(6) (in-plane cis-bend) vibrations of the A (1)A(u) state of C(2)H(2). The v(4)+v(6)=2 vibrational polyad was observed in high-sensitivity one-photon laser-induced fluorescence spectra and the v(4)+v(6)=3 polyad was observed in IR-UV double resonance spectra via the ground state nu(3) (Sigma(+) (u)) and nu(3)+nu(4) (Pi(u)) vibrational levels. The structures of these polyads are dominated by the effects of vibrational angular momentum: Vibrational levels of different symmetry interact via strong a-and b-axis Coriolis coupling, while levels of the same symmetry interact via Darling-Dennison resonance, where the interaction parameter has the exceptionally large value K(4466)=-51.68 cm(-1). The K-structures of the polyads bear almost no resemblance to the normal asymmetric top patterns, and many local avoided crossings occur between close-lying levels with nominal K-values differing by one or more units. Least squares analysis shows that the coupling parameters change only slightly with vibrational excitation, which has allowed successful predictions of the structures of the higher polyads: A number of weak bands from the v(4)+v(6)=4 and 5 polyads have been identified unambiguously. The state discovered by Scherer et al. [J. Chem. Phys. 85, 6315 (1986)], which appears to interact with the K=1 levels of the 3(3) vibrational state at low J, is identified as the second highest of the five K=1 members of the v(4)+v(6)=4 polyad. After allowing for the Darling-Dennison resonance, the zero-order bending structure can be represented by omega(4)=764.71, omega(6)=772.50, x(44)=0.19, x(66)=-4.23, and x(46)=11.39 cm(-1). The parameters x(46) and K(4466) are both sums of contributions from the vibrational angular momentum and from the anharmonic force field. For x(46) these contributions are 14.12 and -2.73 cm(-1), respectively, while the corresponding values for K(4466) are -28.24 and -23

  10. The Obliquity Distribution of Near-Earth Asteroids

    Science.gov (United States)

    Chesley, Steven R.; Farnocchia, D.; Cotto-Figueroa, D.; Statler, T. S.

    2013-05-01

    Abstract (2,250 Maximum Characters): Direct estimates of the Yarkovsky effect on near-Earth asteroids (NEAs) indicate that detectable semimajor axis drift rates are approximately 2-4 times more likely to be negative than positive (Nugent et al., AJ 144, 2012; Farnocchia et al., Icarus in press, 2013). The Yarkovsky effect induces a semimajor axis drift rate that is proportional to the cosine of the obliquity, and thus the excess of negative drift rates suggests an excess of retrograde rotation among the NEAs. This reinforces an earlier result from light curve inversion techniques (La Spina et al., Nature 428, 2004). The retrograde excess is presumed to arise from the nu6 resonance, which is situated near the inner edge of the main belt. Main-belt asteroids that are Yarkovsky-driven into the near-Earth region via the nu6 resonance must have a negative semimajor axis drift and therefore retrograde rotation, leading to an overabundance of retrograde rotators, even though other source regions may have parity between retrograde and direct rotators. The Yarkovsky detections do not directly shed light on the relative presence of mid-range obliquities, which tend to have low drift rates and therefore fail to yield statistically significant drift estimates, but they do present significantly different selection effects when compared to light curve inversions. We present preliminary results from our effort to derive independent constraints on the obliquity distribution of NEAs based on the distribution of estimated semimajor axis drift rates among the NEA population and their associated uncertainties. Our approach to solving the inverse problem starts by deriving the drift rates and associated signal-to-noise ratios for a semi-synthetic NEA population that assumes a parameterized obliquity distribution. The parameters are adjusted until the simulated distributions match the observed distributions, yielding not only an estimated distribution, but also uncertainties and

  11. Meteorite Source Regions as Revealed by the Near-Earth Object Population

    Science.gov (United States)

    Binzel, Richard P.; DeMeo, Francesca E.; Burt, Brian J.; Polishook, David; Burbine, Thomas H.; Bus, Schelte J.; Tokunaga, Alan; Birlan, Mirel

    2014-11-01

    Spectroscopic and taxonomic information is now available for 1000 near-Earth objects, having been obtained through both targeted surveys (e.g. [1], [2], [3]) or resulting from all-sky surveys (e.g. [4]). We determine their taxonomic types in the Bus-DeMeo system [5] [6] and subsequently examine meteorite correlations based on spectral analysis (e.g. [7],[8]). We correlate our spectral findings with the source region probabilities calculated using the methods of Bottke et al. [9]. In terms of taxonomy, very clear sources are indicated: Q-, Sq-, and S-types most strongly associated with ordinary chondrite meteorites show clear source signatures through the inner main-belt. V-types are relatively equally balanced between nu6 and 3:1 resonance sources, consistent with the orbital dispersion of the Vesta family. B- and C-types show distinct source region preferences for the outer belt and for Jupiter family comets. A Jupiter family comet source predominates for the D-type near-Earth objects, implying these "asteroidal" bodies may be extinct or dormant comets [10]. Similarly, near-Earth objects falling in the spectrally featureless "X-type" category also show a strong outer belt and Jupiter family comet source region preference. Finally the Xe-class near-Earth objects, which most closely match the spectral properties of enstatite achondrite (aubrite) meteorites seen in the Hungaria region[11], show a source region preference consistent with a Hungaria origin by entering near-Earth space through the Mars crossing and nu6 resonance pathways. This work supported by the National Science Foundation Grant 0907766 and NASA Grant NNX10AG27G.[1] Lazzarin, M. et al. (2004), Mem. S. A. It. Suppl. 5, 21. [2] Thomas, C. A. et al. (2014), Icarus 228, 217. [3] Tokunaga, A. et al. (2006) BAAS 38, 59.07. [4] Hasselmann, P. H., Carvano, J. M., Lazzaro, D. (2011) NASA PDS, EAR-A-I0035-5-SDSSTAX-V1.0. [5] Bus, S.J., Binzel, R.P. (2002). Icarus 158, 146. [6] DeMeo, F.E. et al. (2009), Icarus

  12. Collective and intrinsic structures in sup 1 sup 8 sup 3 W

    CERN Document Server

    Saitoh, T R; Sletten, G; Bark, R A; Bergström, M H; Regan, P; Toermaenen, S; Varmette, P G; Walker, P M; Wheldon, C

    1999-01-01

    The structure of sup 1 sup 8 sup 3 W has been studied by employing the sup 1 sup 7 sup 6 Yb( sup 1 sup 4 C,alpha 3n) reaction at 68 MeV. Five previously known rotational structure with one-quasiparticle configurations have been extended to higher spin states, and five new rotational bands with three- and five-quasiparticle configurations and a gamma-vibration of a one-quasiparticle structure have been newly identified. In the nu 7/2 sup - [503] and nu 11/2 sup + [615] rotational structures, a signal of an admixture of an octupole-vibrational structure has been observed in their in-band B(M1)/B(E2) ratios and g sub K factors. In the K suppi=19 sup - rotational band, a Coriolis effect on the nu 1/2 sup - [510] neutron has been identified. In all, 17 K-forbidden transitions have been observed. Energies of intrinsic states below 4 MeV have been calculated based on the Blocked BCS theory, and they are used in support of the configuration assignments.

  13. Collective and intrinsic structures in {sup 183}W

    Energy Technology Data Exchange (ETDEWEB)

    Saitoh, T.R.; Saitoh-Hashimoto, N.; Sletten, G.; Bark, R.A.; Bergstroem, M.; Regan, P.; Toermaenen, S.; Varmette, P.G.; Walker, P.M.; Wheldon, C

    1999-11-22

    The structure of {sup 183}W has been studied by employing the {sup 176}Yb({sup 14}C,{alpha}3n) reaction at 68 MeV. Five previously known rotational structure with one-quasiparticle configurations have been extended to higher spin states, and five new rotational bands with three- and five-quasiparticle configurations and a {gamma}-vibration of a one-quasiparticle structure have been newly identified. In the {nu}7/2{sup -}[503] and {nu}11/2{sup +}[615] rotational structures, a signal of an admixture of an octupole-vibrational structure has been observed in their in-band B(M1)/B(E2) ratios and g{sub K} factors. In the K{sup {pi}}=19{sup -} rotational band, a Coriolis effect on the {nu}1/2{sup -}[510] neutron has been identified. In all, 17 K-forbidden transitions have been observed. Energies of intrinsic states below 4 MeV have been calculated based on the Blocked BCS theory, and they are used in support of the configuration assignments.

  14. Erratum to 'Collective and intrinsic structures in sup 1 sup 8 sup 3 W' [Nucl. Phys. A 660 (1999) 171-196

    CERN Document Server

    Saitoh, T R; Sletten, G; Bark, R A; Bergström, M H; Regan, P; Toermaenen, S; Varmette, P G; Walker, P M; Wheldon, C

    2000-01-01

    The structure of sup 1 sup 8 sup 3 W has been studied by employing the sup 1 sup 7 sup 6 Yb( sup 1 sup 4 C,alpha 3n) reaction at 68 MeV. Five previously known rotational structure with one-quasiparticle configurations have been extended to higher spin states, and five new rotational bands with three- and five-quasiparticle configurations and a gamma-vibration of a one-quasiparticle structure have been newly identified. In the nu 7/2 sup - [503] and nu 11/2 sup + [615] rotational structures, a signal of an admixture of an octupole-vibrational structure has been observed in their in-band B(M1)/B(E2) ratios and g sub K factors. In the K suppi=19 sup - rotational band, a Coriolis effect on the nu 1/2 sup - [510] neutron has been identified. In all, 17 K-forbidden transitions have been observed. Energies of intrinsic states below 4 MeV have been calculated based on the Blocked BCS theory, and they are used in support of the configuration assignments.

  15. Erratum to 'Collective and intrinsic structures in {sup 183}W' [Nucl. Phys. A 660 (1999) 171-196

    Energy Technology Data Exchange (ETDEWEB)

    Saitoh, T.R.; Saitoh-Hashimoto, N.; Sletten, G.; Bark, R.A.; Bergstroem, M.; Regan, P.; Toermaenen, S.; Varmette, P.G.; Walker, P.M.; Wheldon, C

    2000-04-24

    The structure of {sup 183}W has been studied by employing the {sup 176}Yb({sup 14}C,{alpha}3n) reaction at 68 MeV. Five previously known rotational structure with one-quasiparticle configurations have been extended to higher spin states, and five new rotational bands with three- and five-quasiparticle configurations and a {gamma}-vibration of a one-quasiparticle structure have been newly identified. In the {nu}7/2{sup -}[503] and {nu}11/2{sup +}[615] rotational structures, a signal of an admixture of an octupole-vibrational structure has been observed in their in-band B(M1)/B(E2) ratios and g{sub K} factors. In the K{sup {pi}}=19{sup -} rotational band, a Coriolis effect on the {nu}1/2{sup -}[510] neutron has been identified. In all, 17 K-forbidden transitions have been observed. Energies of intrinsic states below 4 MeV have been calculated based on the Blocked BCS theory, and they are used in support of the configuration assignments.

  16. Spectral and Timing Evolution of the Black Hole X-ray Nova 4U 1543-47 During its 2002 Outburst

    CERN Document Server

    Park, S Q; McClintock, J E; Remillard, R A; Orosz, J A; Shrader, C R; Hunstead, R W; Campbell-Wilson, D; Ishwara-Chandra, C H; Rao, A P; Rupen, M P

    2003-01-01

    We present an X-ray spectral and timing analysis of 4U 1543-47 during its 2002 outburst based on 49 pointed observations obtained using the Rossi X-ray Timing Explorer (RXTE). The outburst reached a peak intensity of 4.2 Crab in the 2-12 keV band and declined by a factor of 32 throughout the month-long observation. A 21.9 +- 0.6 mJy radio flare was detected at 1026.75 MHz two days before the X-ray maximum; the radio source was also detected late in the outburst, after the X-ray source entered the low hard state. The X-ray light curve exhibits the classic shape of a rapid rise and an exponential decay. The spectrum is soft and dominated by emission from the accretion disk. The continuum is fit with a multicolor disk blackbody (kT_{max} = 1.04 keV) and a power-law (Gamma ~ 2.7). Midway through the decay phase, a strong low-frequency QPO (nu = 7.3-8.1 Hz) was present for several days. The spectra feature a broad Fe K alpha line that is asymmetric, suggesting that the line is due to relativistic broadening rather...

  17. Bandoniozyma gen. nov., a genus of fermentative and non-fermentative tremellaceous yeast species.

    Directory of Open Access Journals (Sweden)

    Patricia Valente

    Full Text Available BACKGROUND: Independent surveys across the globe led to the proposal of a new basidiomycetous yeast genus within the Bulleromyces clade of the Tremellales, Bandoniozyma gen. nov., with seven new species. METHODOLOGY/PRINCIPAL FINDINGS: The species were characterized by multiple methods, including the analysis of D1/D2 and ITS nucleotide sequences, and morphological and physiological/biochemical traits. Most species can ferment glucose, which is an unusual trait among basidiomycetous yeasts. CONCLUSIONS/SIGNIFICANCE: In this study we propose the new yeast genus Bandoniozyma, with seven species Bandoniozyma noutii sp. nov. (type species of genus; CBS 8364(T  =  DBVPG 4489(T, Bandoniozyma aquatica sp. nov. (UFMG-DH4.20(T  =  CBS 12527(T  =  ATCC MYA-4876(T, Bandoniozyma complexa sp. nov. (CBS 11570(T  =  ATCC MYA-4603(T  =  MA28a(T, Bandoniozyma fermentans sp. nov. (CBS 12399(T  =  NU7M71(T  =  BCRC 23267(T, Bandoniozyma glucofermentans sp. nov. (CBS 10381(T  =  NRRL Y-48076(T  =  ATCC MYA-4760(T  =  BG 02-7-15-015A-1-1(T, Bandoniozyma tunnelae sp. nov. (CBS 8024(T  =  DBVPG 7000(T, and Bandoniozyma visegradensis sp. nov. (CBS 12505(T  =  NRRL Y-48783(T  =  NCAIM Y.01952(T.

  18. Turbulence beneath finite amplitude water waves

    Energy Technology Data Exchange (ETDEWEB)

    Beya, J.F. [Universidad de Valparaiso, Escuela de Ingenieria Civil Oceanica, Facultad de Ingenieria, Valparaiso (Chile); The University of New South Wales, Water Research Laboratory, School of Civil and Environmental Engineering, Sydney, NSW (Australia); Peirson, W.L. [The University of New South Wales, Water Research Laboratory, School of Civil and Environmental Engineering, Sydney, NSW (Australia); Banner, M.L. [The University of New South Wales, School of Mathematics and Statistics, Sydney, NSW (Australia)

    2012-05-15

    Babanin and Haus (J Phys Oceanogr 39:2675-2679, 2009) recently presented evidence of near-surface turbulence generated below steep non-breaking deep-water waves. They proposed a threshold wave parameter a {sup 2}{omega}/{nu} = 3,000 for the spontaneous occurrence of turbulence beneath surface waves. This is in contrast to conventional understanding that irrotational wave theories provide a good approximation of non-wind-forced wave behaviour as validated by classical experiments. Many laboratory wave experiments were carried out in the early 1960s (e.g. Wiegel 1964). In those experiments, no evidence of turbulence was reported, and steep waves behaved as predicted by the high-order irrotational wave theories within the accuracy of the theories and experimental techniques at the time. This contribution describes flow visualisation experiments for steep non-breaking waves using conventional dye techniques in the wave boundary layer extending above the wave trough level. The measurements showed no evidence of turbulent mixing up to a value of a {sup 2}{omega}/{nu} = 7,000 at which breaking commenced in these experiments. These present findings are in accord with the conventional understandings of wave behaviour. (orig.)

  19. First Detection of Vibrational Spectra of the Vinyl and Hexatriynyl Radicals

    Science.gov (United States)

    Doyle, Timothy John

    The first vibrational spectrum of the C _2H_3 (vinyl) radical has been identified in an FTIR study of the vacuum ultraviolet (VUV) photolysis products of ethylene (C_2 H_4) and its D- and ^{13}C-substituted isotopomers and acetylene (C_2H_2) + HI trapped in Ar at 10 K. Absorptions at 900.2 and 685.4 cm^{-1} have been assigned to the nu_8(a^ {''}), out-of-plane wagging and the nu_7(a^'), in-plane asymmetric CH_2 bending - alphaCH bending modes. The assignments are supported by the isotopic data and by comparison with the results of a GVB ab initio calculation by Dupuis and Wendoloski, and an MBPT(2) ab initio calculation. A similar FTIR study of the products of the VUV photolysis of acetylene (C_2H _2) and 1,3-butadiene (C_4 H_6) trapped in solid Ar has resulted in the first identification of a vibration of the C_6H (hexatriynyl) radical at 1953.4 cm^{-1}. Various D and ^{13}C isotopomers have been observed. The complex, overlapping spectra resulting from partial ^{13}C substitution have been fitted using a force constant adjustment calculation and support the assignment of the 1953.4 cm^ {-1} absorption to a Cequiv C stretching fundamental of linear C_6 H.

  20. Bandoniozyma gen. nov., a Genus of Fermentative and Non-Fermentative Tremellaceous Yeast Species

    Science.gov (United States)

    Landell, Melissa Fontes; Crestani, Juliana; Pagnocca, Fernando Carlos; Sette, Lara Durães; Passarini, Michel Rodrigo Zambrano; Rosa, Carlos Augusto; Brandão, Luciana R.; Pimenta, Raphael S.; Ribeiro, José Roberto; Garcia, Karina Marques; Lee, Ching-Fu; Suh, Sung-Oui; Péter, Gábor; Dlauchy, Dénes; Fell, Jack W.; Scorzetti, Gloria; Theelen, Bart; Vainstein, Marilene H.

    2012-01-01

    Background Independent surveys across the globe led to the proposal of a new basidiomycetous yeast genus within the Bulleromyces clade of the Tremellales, Bandoniozyma gen. nov., with seven new species. Methodology/Principal Findings The species were characterized by multiple methods, including the analysis of D1/D2 and ITS nucleotide sequences, and morphological and physiological/biochemical traits. Most species can ferment glucose, which is an unusual trait among basidiomycetous yeasts. Conclusions/Significance In this study we propose the new yeast genus Bandoniozyma, with seven species Bandoniozyma noutii sp. nov. (type species of genus; CBS 8364T  =  DBVPG 4489T), Bandoniozyma aquatica sp. nov. (UFMG-DH4.20T  =  CBS 12527T  =  ATCC MYA-4876T), Bandoniozyma complexa sp. nov. (CBS 11570T  =  ATCC MYA-4603T  =  MA28aT), Bandoniozyma fermentans sp. nov. (CBS 12399T  =  NU7M71T  =  BCRC 23267T), Bandoniozyma glucofermentans sp. nov. (CBS 10381T  =  NRRL Y-48076T  =  ATCC MYA-4760T  =  BG 02-7-15-015A-1-1T), Bandoniozyma tunnelae sp. nov. (CBS 8024T  =  DBVPG 7000T), and Bandoniozyma visegradensis sp. nov. (CBS 12505T  =  NRRL Y-48783T  =  NCAIM Y.01952T). PMID:23056233

  1. Distinct structures and environments for the three hemes of the cytochrome bc1 complex from Rhodospirillum rubrum. A resonance Raman study using B-band excitations.

    Science.gov (United States)

    Le Moigne, C; Schoepp, B; Othman, S; Verméglio, A; Desbois, A

    1999-01-19

    The B-band excited resonance Raman (RR) spectra (100-1700 cm-1) of the bacterial cytochrome bc1 complex purified from Rhodospirillum rubrum are reported. Four redox states, i.e., the persulfate-oxidized, "as prepared", and ascorbate- and dithionite-reduced states of the complex, were investigated with the laser excitations at 406.7, 413.1, and 441.6 nm. Following the different absorption properties of the b- and c-type hemes and the different resonance enhancements of the vibrational modes of oxidized and reduced hemes, RR contributions from the b- and c-type hemes were characterized. For the nu2, nu10, and nu8 porphyrin vibrational modes, individual contributions of hemes c1, bH, and bL were determined. The data show that the macrocycle conformation of the three hemes of the cytochrome bc1 complex is different. In particular, the frequencies assigned to ferrous heme bL (1580, 1610, and 352 cm-1, respectively) reveal that its porphyrin is more strongly distorted than that of ferrous heme bH (1584, 1614, and 344 cm-1, respectively). The frequencies of the nu11 modes (1543, 1536, and 1526 cm-1 for ferrous heme c1, heme bH, and heme bL, respectively) confirm that the axial histidylimidazole ligands of heme bL have a marked anionic character. Strong differences in the peripheral interactions of the three hemes with the proteins were also detected through the frequency differences of the nu5, nu13, nu14, and nu42 modes. Considering that hemes bH and bL are inserted into a four-helice bundle, the RR data are interpreted in the frame of a strong protein constraint on heme bL.

  2. a Measurement of the Inclusive Semileptonic Branching Fractions and Lifetime Ratio of the B

    Science.gov (United States)

    Lambrecht, Mark Alan

    Separate measurements of the B_ {u} and B_{d} semileptonic branching fractions have been made using 1.4 fb^{-1} of data taken with the CLEO-II detector at the Upsilon(4S) resonance. A new technique is utilized in which a | B meson is exclusively reconstructed in order to tag the charge and flavor. Approximately 2000 fully reconstructed candidates are found in the data sample. Since the Upsilon(4S) decays to B | B, the tracks from the B meson can then be examined for lepton content. The efficiency corrected ratio of the number of leptons and the number of tags determines the semileptonic branching fractions. This method allows for the first separate measurement of the charged B meson semileptonic branching ratio in contrast to other techniques which measure the flavor averaged branching fractions. Assuming that the partial semileptonic decay widths of the charged and neutral B's are equal, the lifetime ratio can be measured from the ratio of semileptonic branching fractions. Since the flavor is explicitly tagged, no assumptions concerning the production fractions of the B_ {u} and B_{d} (f_{+-} and f_ {00}) are used, unlike results of past Upsilon(4S) experiments. Hence, with the exception of the partial semileptonic width equality, the only assumption used is that of the shape of the direct lepton (Btol X) momentum spectrum in efficiency determination. Theoretical dependence is thus kept at a minimum. The measured results for the branching fractions and lifetime ratio are: (UNFORMATTED TABLE OR EQUATION FOLLOWS)eqalign{{cal B}(B^+to Xl^+nu) &= (13.0 +/- 1.8 +/- 1.6)%cr { cal B}(B^0to Xl^+ nu) &= (14.5 +/- 2.1 +/- 1.9)%cr {tau(B^+)overtau(B^0) } &= 0.90 +/- 0.18 +/- 0.12.cr} (TABLE/EQUATION ENDS).

  3. VLT/SPHERE observations and shape reconstruction of asteroid (6) Hebe

    Science.gov (United States)

    Marsset, Michael; Carry, Benoit; Dumas, Christophe; Vernazza, Pierre; Jehin, Emmanuel; Sonnett, Sarah M.; Fusco, Thierry

    2016-10-01

    (6) Hebe is a large main-belt asteroid, accounting for about half a percent of the mass of the asteroid belt. Its spectral characteristics and close proximity to dynamical resonances within the main-belt (the 3:1 Kirkwood gap and the nu6 resonance) make it a probable parent body of the H-chondrites and IIE iron meteorites found on Earth.We present new AO images of Hebe obtained with the high-contrast imager SPHERE (Beuzit et al. 2008) as part of the science verification of the instrument. Hebe was observed close to its opposition date and throughout its rotation in order to derive its 3-D shape, and to allow a study of its surface craters. Our observations reveal impact zones that witness a severe collisional disruption for this asteroid. When combined to previous AO images and available lightcurves (both from the literature and from recent optical observations by our team), these new observations allow us to derive a reliable shape model using our KOALA algorithm (Carry et al. 2010). We further derive an estimate of Hebe's density based on its known astrometric mass.

  4. Understanding native Russian listeners' errors on an English word recognition test: model-based analysis of phoneme confusion.

    Science.gov (United States)

    Shi, Lu-Feng; Morozova, Natalia

    2012-08-01

    Word recognition is a basic component in a comprehensive hearing evaluation, but data are lacking for listeners speaking two languages. This study obtained such data for Russian natives in the US and analysed the data using the perceptual assimilation model (PAM) and speech learning model (SLM). Listeners were randomly presented 200 NU-6 words in quiet. Listeners responded verbally and in writing. Performance was scored on words and phonemes (word-initial consonants, vowels, and word-final consonants). Seven normal-hearing, adult monolingual English natives (NM), 16 English-dominant (ED), and 15 Russian-dominant (RD) Russian natives participated. ED and RD listeners differed significantly in their language background. Consistent with the SLM, NM outperformed ED listeners and ED outperformed RD listeners, whether responses were scored on words or phonemes. NM and ED listeners shared similar phoneme error patterns, whereas RD listeners' errors had unique patterns that could be largely understood via the PAM. RD listeners had particular difficulty differentiating vowel contrasts /i-I/, /æ-ε/, and /ɑ-Λ/, word-initial consonant contrasts /p-h/ and /b-f/, and word-final contrasts /f-v/. Both first-language phonology and second-language learning history affect word and phoneme recognition. Current findings may help clinicians differentiate word recognition errors due to language background from hearing pathologies.

  5. The study and development of the empirical correlations equation of natural convection heat transfer on vertical rectangular sub-channels

    Science.gov (United States)

    Kamajaya, Ketut; Umar, Efrizon; Sudjatmi, K. S.

    2012-06-01

    This study focused on natural convection heat transfer using a vertical rectangular sub-channel and water as the coolant fluid. To conduct this study has been made pipe heaters are equipped with thermocouples. Each heater is equipped with five thermocouples along the heating pipes. The diameter of each heater is 2.54 cm and 45 cm in length. The distance between the central heating and the pitch is 29.5 cm. Test equipment is equipped with a primary cooling system, a secondary cooling system and a heat exchanger. The purpose of this study is to obtain new empirical correlations equations of the vertical rectangular sub-channel, especially for the natural convection heat transfer within a bundle of vertical cylinders rectangular arrangement sub-channels. The empirical correlation equation can support the thermo-hydraulic analysis of research nuclear reactors that utilize cylindrical fuel rods, and also can be used in designing of baffle-free vertical shell and tube heat exchangers. The results of this study that the empirical correlation equations of natural convection heat transfer coefficients with rectangular arrangement is Nu = 6.3357 (Ra.Dh/x)0.0740.

  6. [Factors influencing long-term survival in patients with nonoperable lung cancer: an analysis by Cox model].

    Science.gov (United States)

    Dong, W; Zhao, W; Sun, L

    1996-09-01

    This paper reports a prospective survey of 173 patients with nonoperable lung cancer between January. 1, 1983 to March. 1, 1985. The follow-up rate was 97.7% over five years. Fourteen factors including sex, age, course of disease before treatment, clinical stage, performance status, size of mass, metastatic status, hemoglobin before treatment, short-term response to treatment and so on which might influence long term survival were studied by univariate analysis (Kruskal-Wallis test for Kaplan-Meier survival curve) and by multivariate analysis (Cox's proportional hazad model and audio-visual chart test for goodness of fit). Multivariate analysis using Cox's model revealed 6 significant prognostic factors: performance status, short-term response to treatment, clinical stage, hemoglobin before treatment, smoking index and method of treatment. The survival prediction equation was chi 2 = 72.14, nu = 6, P < 0.0001. The results indicate that the performance status and the CR rate of the initial treatment, among other things, is the major factors affecting prognosis.

  7. Gas-phase infrared multiple photon dissociation spectroscopy of isolated SF6- and SF5- anions.

    Science.gov (United States)

    Steill, Jeffrey D; Oomens, Jos; Eyler, John R; Compton, Robert N

    2008-12-28

    Resonantly enhanced multiple photon dissociation of gas-phase SF(6) (-) and SF(5) (-) is studied using tunable infrared light from the FELIX free electron laser. The photodissociation spectrum of the sulfur hexafluoride anion, producing SF(5) (-), is recorded over the spectral range of 250-1650 cm(-1). The infrared multiple photon dissociation cross section exhibits a strong, broad resonance enhancement at 675 cm(-1) in agreement with the calculated value of nu(3), one of the two IR-active fundamental vibrational modes predicted for the O(h)-symmetry ion. Much weaker absorption features are observed in the spectral region of 300-450 cm(-1) as well as at 580 cm(-1) that are not easily assigned to the other IR-active fundamental of SF(6) (-) since these resonances are observed at a much higher energy than the calculated values for the IR-active nu(4) mode. The potential role of binary combination bands is considered. Photodissociation from the sulfur pentafluoride anion produced only F(-), but photodetachment was also observed through SF(6) associative electron capture. The IR multiple photon dissociation spectrum of SF(5) (-) shows multiple resonances within the region of 400-900 cm(-1) and agreement with calculations is clear, including the observation of three fundamental frequencies: nu(1) at 780 cm(-1), nu(7) at 595 cm(-1), and nu(8) at 450 cm(-1). Comparisons of the measured frequencies with ab initio and density functional theory calculations confirm an SF(5) (-) anion of C(4v) symmetry. Similar comparisons for SF(6) (-) are not inconsistent with an anion of O(h) symmetry.

  8. A Search for B-→ τ- v-bar Recoiling Against a Fully Reconstructed B

    Energy Technology Data Exchange (ETDEWEB)

    Cartaro, Concetta

    2003-04-23

    We present a search for the B- → τ- v-bar decay in a data sample of 82 fb- collected at the Υ (4S) resonance with the BABAR detector at the SLAC PEP-II asymmetric B Factory. Continuum and combinatorial backgrounds are suppressed by selecting a sample of events with one completely reconstructed B. The decay products of the other B in the event are analyzed to search for a B- → τ- v-bar decay. The τ lepton is identified in the following decay channels: τ- → e - νν-bar τ- → {mu}- {nu}{bar {nu}}, {tau}-{yields} {pi}- {yields} {pi}-{pi}{sup 0}{nu}, τ- {yields} {pi}{sup -}{pi}{sup +}{pi}- {nu}. We find no evidence for a signal and set a 90% C.L. upper limit of B(B{sup -} {yields} τ{sup -}{bar {nu}}) < 7.7 x 10-4. We combine this result with another BABAR measurement searching for B-{yields} τ-} ν-bar decays in a sample with one B meson reconstructed in semi-leptonic channels. The two samples are statistically independent. We obtain a combined 90% C.L. upper limit of B(B- → τ-ν-bar) < 4.1 x 10-4. All results are preliminary.

  9. Characterization of a time-of-flight mass spectrometer and its applications in the study of solid surfaces; Charakterisierung eines Flugzeitmassenspektrometers und seine Anwendungen in der Festkoerperoberflaechenuntersuchung

    Energy Technology Data Exchange (ETDEWEB)

    Mazarov, P.

    2006-12-21

    The object and the purpose of the present work was to develop, to assemble and to start running a new TOF (time of flight) mass spectrometer for imaging SNMS analytic which is optimized for the analysis of highly molecular secondary ions. The most important purpose was the characterization of the TOF mass spectrometer. The obtained mass spectra of indium, tantalum and silver clusters reflect the excellent properties of the TOF mass spectrometer for the detection of large clusters with good detection efficiency up to masses of 16000 amu. The possibility of the deflection of selected saturated atom and cluster peaks serves for further improvement of the detection efficiency for large molecules. The accessible mass resolution was determined to be of the order of m/{delta}m=1000 in the high mass region. Numerous measurements were carried out to characterize the useful yield of this spectrometer. For a best possible adaptation of the TOF mass spectrometer for the detection of highly molecular particles, a device for post-acceleration of the detected particles by up to 10 keV were inserted directly before the MCP detector. The detection efficiency of positive secondary ions was determined for different post-acceleration voltages for the example of sputtered indium cluster ions. In addition, a new method was developed for the quantitative determination of the spectral ionization probability {alpha}{sup +}({nu}) of sputtered particles as a function of the emission velocity. The next application of the TOF mass spectrometer is the analysis of complicated organic molecules in solid state surfaces. During measurements of the photo-ionization behaviour of neutral tryptophan molecules, it was found out that a stable molecular ion signal is generated in the SNMS spectrum with h{nu}=7.9 eV can only be observed by the use of a continuous ion beam or very long (ms range) ion pulses. (orig.)

  10. Light-Driven Contact Hearing Aid for Broad-Spectrum Amplification: Safety and Effectiveness Pivotal Study.

    Science.gov (United States)

    Gantz, Bruce J; Perkins, Rodney; Murray, Michael; Levy, Suzanne Carr; Puria, Sunil

    2017-03-01

    Demonstrate safety and effectiveness of the light-driven contact hearing aid to support FDA clearance. A single-arm, open-label investigational-device clinical trial. Two private-practice and one hospital-based ENT clinics. Forty-three subjects (86 ears) with mild-to-severe bilateral sensorineural hearing impairment. Bilateral amplification delivered via a light-driven contact hearing aid comprising a Tympanic Lens (Lens) with a customized platform to directly drive the umbo and a behind-the-ear sound processor (Processor) that encodes sound into light pulses to wirelessly deliver signal and power to the Lens. The primary safety endpoint was a determination of "no change" (PTA4 hearing at the 120-day measurement interval. The primary efficacy endpoint was improvement in word recognition using NU-6 at the 30-day measurement interval over the baseline unaided case. Secondary efficacy endpoints included functional gain from 2 to 10 kHz and speech-in-noise improvement over the baseline unaided case using both omnidirectional and directional microphones. The results for the 86 ears in the study determined a mean change of -0.40 dB in PTA4, indicating no change in residual hearing (p Hearing in Noise Test was 0.75 dB (p = 0.028) and 3.14 dB (p < 0.0001) for the omnidirectional and directional microphone modes, respectively. The safety and effectiveness data supported a de novo 510(k) submission that received clearance from the FDA.

  11. Long-Lived Dynamical Niches in the Inner Solar System

    Science.gov (United States)

    Cuk, Matija

    2008-05-01

    Despite recent theoretical advances (Gomes et al. 2005, Chambers 2007) the cause of the Late Heavy Bombardment (a.k.a. Lunar Cataclysm) is still controversial. During the LHB, which ended by 3.8 Gya (with no clear start date; Chapman et al. 2007) multiple large impact basins formed on the Moon, and there is some evidence of bombardment on Earth, Mars and Vesta. While leading theories prefer late depletion of the main asteroid belt, trace element data in lunar soils point to overwhelmingly enstatite chondrite impactors, usually associated with the inner solar system. Bottke et al.(2007) have shown that even high-inclination planet-crossing planetesimals decay too fast to be a viable source of the LHB. However, there exist several stable niches, potentially relevant to the LHB. We show that putative Vulcanoids and Earth-Mars-belt asteroids (Evans and Tabachnik 1999) are not plausible sources of the LHB, and that the apparent complete depletion of those regions is likely due to YORP and Yarkovsky effects, rather than any purely dynamical causes. The region between Mars and the asteroid belt does offer a long-term refuge, the stability of which depends crucially on the long-term behavior of Mars's eccentricity (cf. Chambers 2007). If Mars originally had a more circular orbit (long term e < 0.09), small bodies could survive in this region until chaotic dynamics excites martian eccentricity (Laskar 1989, 2008). This scenario is very similar to the "Planet V" hypothesis (Chambers 2007), only that the planet never formed. The amount of mass required for the LHB is roughly similar to that of the asteroid belt, implying much higher small-body density in the transmartian region. This is still a negligible fraction of the material needed to form the inner planets, and would require that this region was not swept by the nu6 secular resonance, unlike the main belt.

  12. The even-even nucleus {sup 196}Hg and its relation to the ''magical quartet'' around {sup 194}Pt

    Energy Technology Data Exchange (ETDEWEB)

    Bernards, Christian; Albers, Michael; Fransen, Christoph; Heinze, Stefan; Jolie, Jan; Radeck, Desiree; Thomas, Tim [Institute for Nuclear Physics, University of Cologne (Germany)

    2009-07-01

    The investigation of {sup 196}Hg - especially the determination of level spins and multipole mixing ratios of {gamma} transitions between low-energy states - is of great interest for testing the existence of a relation between the nucleus {sup 196}Hg and the so-called magical quartet around {sup 194}Pt. Within the U{sub {nu}}(6/12) x U{sub {pi}}(6/4) extended supersymmetry, this quartet is supposed to be the supermultiplet being described the best. Similar to the quartet members {sup 194,195}Pt and {sup 195,196}Au, the nucleus {sup 196}Hg can be described theoretically by seven IBA-2 particles to the shell closure, in particular by two j = 3/2 proton fermions and five sd neutron bosons as a two-fermions - five-bosons supermultiplet member. In order to obtain experimental data on {sup 196}Hg a {gamma}{gamma} angular correlation experiment was performed at the Tandem accelerator of the Institute for Nuclear Physics in Cologne. Using a {sup 4}He beam with an energy of 28 MeV impinging a {sup 194}Pt target the reaction {sup 194}Pt({alpha}, 2n){sup 196}Hg was induced. To analyze the {gamma} decays of yrast and non-yrast {sup 196}Hg states 13 high purity germanium detectors were mounted in the Horus cube {gamma}-ray spectrometer, which allows the determination of level spins and multipole mixing ratios by the analysis of {gamma}{gamma} angular correlations. We discuss first results of the experiment.

  13. Laser induced threshold photoemission magnetic circular dichroism and its application to photoelectron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Takeshi, E-mail: nakagawa@ims.ac.jp [Institute for Molecular Science, Myodaiji-cho, Okazaki, 444-8585 (Japan); The Graduate University for Advanced Studies (Sokendai), Myodaiji-cho, Okazaki, 444-8585 (Japan); Yokoyama, Toshihiko, E-mail: yokoyama@ims.ac.jp [Institute for Molecular Science, Myodaiji-cho, Okazaki, 444-8585 (Japan); The Graduate University for Advanced Studies (Sokendai), Myodaiji-cho, Okazaki, 444-8585 (Japan)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Threshold photoemission magnetic circular dichroism results are presented. Black-Right-Pointing-Pointer The enhanced MCD contrast is used to observe magnetic domains by PEEM. Black-Right-Pointing-Pointer Magnetization axis, probing depth and angle dependence of MCD are described. Black-Right-Pointing-Pointer Laser based measurements in this method expand the possibility of PEEM. -- Abstract: This work enlightens the threshold photoemission magnetic circular dichroism (MCD) and its adaption on photoemission electron microscopy (PEEM) using lasers. MCD is a simple and efficient way to investigate magnetic properties since it does not need any spin analyzers with low efficiency, and thus the MCD related techniques have developed to observe magnetic domains. Usually, MCD in a total yield measurement in the valence band with weak spin-orbit coupling (SOC) excited by low photon energy (h{nu}{<=} 6 eV) does not compete with the X-ray magnetic circular dichroism (XMCD) with strong SOC. XMCD PEEM observation of magnetic domains has been successfully established while MCD PEEM derived from valence bands has not been. However, using angle and energy resolved photoelectron, valence band MCD provides large asymmetry similar to that by XMCD. Threshold measurement of photoelectron in a total electron yield procedure can take advantage of the measurement of photoelectrons with a limited angle and energy mode. This restriction of the photoelectron makes the threshold MCD technique an efficient way to get magnetic information and gives more than 10% asymmetry for Ni/Cu(0 0 1), which is comparable to that obtained by angle resolved photoemission. Thus the threshold MCD technique is a suitable method to observe magnetic domains by PEEM. For threshold MCD, incident angle dependence and high sensitivity to out-of-plane magnetized films compared with in-plane ones are discussed. Ultrashort pulse lasers make it feasible to measure two photon

  14. An astrometric search for a stellar companion to the sun

    Energy Technology Data Exchange (ETDEWEB)

    Perlmutter, S.

    1986-11-25

    A companion star within 0.8 pc of the Sun has been postulated to explain a possible 26 Myr periodicity in mass extinctions of species on the Earth. Such a star would already be catalogued in the Yale Bright Star catalogue unless it is fainter than m/sub nu/ = 6.5; this limits the possible stellar types for an unseen companion to red dwarfs, brown dwarfs, or compact objects. Red dwarfs account for about 75% of these possible stars. We describe here the design and development of an astrometric search for a nearby red dwarf companion with a six-month peak-to-peak parallax of greater than or equal to2.5 arcseconds. We are measuring the parallax of 2770 candidate faint red stars selected from the Dearborn Observatory catalogue. An automated 30-inch telescope and CCD camera system collect digitized images of the candidate stars, along with a 13' x 16' surrounding field of background stars. Second-epoch images, taken a few months later, are registered to the first epoch images using the background stars as fiducials. An apparent motion, m/sub a/, of the candidate stars is found to a precision of sigma/sub m//sub a/ approx. = 0.08 pixel approx. = 0.2 arcseconds for fields with N/sub fiducial/ greater than or equal to 10 fiducial stars visible above the background noise. This precision is sufficient to detect the parallactic motion of a star at 0.8 pc with a two month interval between the observation epochs. Images with fewer fiducial stars above background noise are observed with a longer interval between epochs. If a star is found with high parallactic motion, we will confirm its distance with further parallax measurements, photometry, and spectral studies, and will measure radial velocity and proper motion to establish its orbit. We have demonstrated the search procedure with observations of 41 stars, and have shown that none of these is a nearby star. 37 refs., 16 figs., 3 tabs.

  15. Dynamical and Physical Properties of 65803 Didymos, the Proposed AIDA Mission Target

    Science.gov (United States)

    Richardson, Derek C.; Barnouin, Olivier S.; Benner, Lance A. M.; Bottke, William; Campo Bagatin, Adriano; Cheng, Andrew F.; Eggl, Siegfried; Hamilton, Douglas P.; Hestroffer, Daniel; Hirabayashi, Masatoshi; Maurel, Clara; McMahon, Jay W.; Michel, Patrick; Murdoch, Naomi; Naidu, Shantanu P.; Pravec, Petr; Rivkin, Andrew S.; Rosenblatt, Pascal; Sarid, Gal; Scheeres, Daniel J.; Scheirich, Peter; Tsiganis, Kleomenis; Zhang, Yun; AIDA Dynamical and Physical Properties of Didymos Working Group

    2016-10-01

    Binary near-Earth asteroid (NEA) 65803 Didymos is the proposed Asteroid Impact & Deflection Assessment (AIDA) mission target, combining an orbiter [1] and a kinetic impactor for a planned encounter in fall 2022 [2]. The Dynamical and Physical Properties of Didymos Working Group supports this mission by addressing questions related to understanding the dynamical state of the system and inferring physical properties. Didymos is an Apollo-class NEA that likely reached its current orbit by exiting the inner main belt near or within the nu-6 resonance (> 82% chance) [3]. Remote observations [4] show Didymos is spectroscopically most consistent with ordinary chondrites. The diameters of the binary components are measured to be about 780 and 160 m [5]. A model of the short-term binary dynamics suggests possible librations of the secondary with up to ~10-deg amplitude, depending on its axial ratio. However, an equilibrium orbital and rotational solution is consistent with a libration amplitude of only ~1 deg. The primary, with an estimated 2.1 g/cc bulk density (uncertainty 30%) has a possibly super-critical rotation period of 2.26 h that may imply a cohesive strength of several tens of Pa. At this rate, perturbed regolith material may go through take-off/landing cycles and cause loss of fines due to solar radiation pressure. Based on a continuum analysis [6], the internal structure would likely fail before the equatorial region. A discrete analysis [7,8] shows that a minimum of 2.5 g/cc bulk density is needed for the structure to hold without cohesion. The system may be subject to weak thermal radiation forces (BYORP) with a period drift of no greater than 1 s/yr [9]. Experiments using the ISAE-SUPAERO drop tower [10] are underway to model the possible deployment of a lander on the secondary. References: [1] Michel et al. 2016, ASR 57, 2529; [2] Cheng et al. 2016, P&SS 127, 27; [3] Granvik et al. 2015, DPS 47, 214.07; [4] Dunn et al. 2013, LPSC 44, 1719; [5] Osip et al

  16. Origins and Asteroid Main-Belt Stratigraphy for H-, L-, LL-Chondrite Meteorites

    Science.gov (United States)

    Binzel, Richard; DeMeo, Francesca; Burbine, Thomas; Polishook, David; Birlan, Mirel

    2016-10-01

    We trace the origins of ordinary chondrite meteorites to their main-belt sources using their (presumably) larger counterparts observable as near-Earth asteroids (NEAs). We find the ordinary chondrite stratigraphy in the main belt to be LL, H, L (increasing distance from the Sun). We derive this result using spectral information from more than 1000 near-Earth asteroids [1]. Our methodology is to correlate each NEA's main-belt source region [2] with its modeled mineralogy [3]. We find LL chondrites predominantly originate from the inner edge of the asteroid belt (nu6 region at 2.1 AU), H chondrites from the 3:1 resonance region (2.5 AU), and the L chondrites from the outer belt 5:2 resonance region (2.8 AU). Each of these source regions has been cited by previous researchers [e.g. 4, 5, 6], but this work uses an independent methodology that simultaneously solves for the LL, H, L stratigraphy. We seek feedback from the planetary origins and meteoritical communities on the viability or implications of this stratrigraphy.Methodology: Spectroscopic and taxonomic data are from the NASA IRTF MIT-Hawaii Near-Earth Object Spectroscopic Survey (MITHNEOS) [1]. For each near-Earth asteroid, we use the Bottke source model [2] to assign a probability that the object is derived from five different main-belt source regions. For each spectrum, we apply the Shkuratov model [3] for radiative transfer within compositional mixing to derive estimates for the ol / (ol+px) ratio (and its uncertainty). The Bottke source region model [2] and the Shkuratov mineralogic model [3] each deliver a probability distribution. For each NEA, we convolve its source region probability distribution with its meteorite class distribution to yield a likelihood for where that class originates. Acknowledgements: This work supported by the National Science Foundation Grant 0907766 and NASA Grant NNX10AG27G.References: [1] Binzel et al. (2005), LPSC XXXVI, 36.1817. [2] Bottke et al. (2002). Icarus 156, 399. [3

  17. Performance of a Steel/Oxide Composite Waste Form for Combined Waste Steams from Advanced Electrochemical Processes

    Energy Technology Data Exchange (ETDEWEB)

    Indacochea, J. E. [Univ. of Illinois, Chicago, IL (United States); Gattu, V. K. [Univ. of Illinois, Chicago, IL (United States); Chen, X. [Univ. of Illinois, Chicago, IL (United States); Rahman, T. [Univ. of Illinois, Chicago, IL (United States)

    2017-06-15

    The results of electrochemical corrosion tests and modeling activities performed collaboratively by researchers at the University of Illinois at Chicago and Argonne National Laboratory as part of workpackage NU-13-IL-UIC-0203-02 are summarized herein. The overall objective of the project was to develop and demonstrate testing and modeling approaches that could be used to evaluate the use of composite alloy/ceramic materials as high-level durable waste forms. Several prototypical composite waste form materials were made from stainless steels representing fuel cladding, reagent metals representing metallic fuel waste streams, and reagent oxides representing oxide fuel waste streams to study the microstructures and corrosion behaviors of the oxide and alloy phases. Microelectrodes fabricated from small specimens of the composite materials were used in a series of electrochemical tests to assess the corrosion behaviors of the constituent phases and phase boundaries in an aggressive acid brine solution at various imposed surface potentials. The microstructures were characterized in detail before and after the electrochemical tests to relate the electrochemical responses to changes in both the electrode surface and the solution composition. The results of microscopic, electrochemical, and solution analyses were used to develop equivalent circuit and physical models representing the measured corrosion behaviors of the different materials pertinent to long-term corrosion behavior. This report provides details regarding (1) the production of the composite materials, (2) the protocol for the electrochemical measurements and interpretations of the responses of multi-phase alloy and oxide composites, (3) relating corrosion behaviors to microstructures of multi-phase alloys based on 316L stainless steel and HT9 (410 stainless steel was used as a substitute) with added Mo, Ni, and/or Mn, and (4) modeling the corrosion behaviors and rates of several alloy/oxide composite

  18. Electronic structure and physical properties of Heusler compounds for thermoelectric and spintronic applications

    Energy Technology Data Exchange (ETDEWEB)

    Ouardi, Siham

    2012-03-19

    sensitive HAXPES. The linear behavior of the spectra close to {epsilon}F proves the bulk origin of Dirac-cone type density of states. Furthermore, a systematic study on the optical and transport properties of PtYSb is presented. The compound exhibits promising thermoelectric properties with a high figure of merit (ZT=0.2) and a Hall mobility {mu}h of 300 cm{sup 2}/Vs at 350 K. The last part of this thesis describes the linear dichroism in angular-resolved photoemission from the valence band of NiTi{sub 0.9}Sc{sub 0.1}Sn and NiMnSb. High resolution photoelectron spectroscopy was performed with an excitation energy of h{nu}=7.938 keV. The linear polarization of the photons was changed using an in-vacuum diamond phase retarder. Noticeable linear dichroism is found in the valence bands and this allows for a symmetry analysis of the contributing states. The differences in the spectra are found to be caused by symmetry dependent angular asymmetry parameters, and these occur even in polycrystalline samples without preferential crystallographic orientation.