WorldWideScience

Sample records for 2 20 kev range

  1. QUIET-TIME INTERPLANETARY {approx}2-20 keV SUPERHALO ELECTRONS AT SOLAR MINIMUM

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Linghua [Department of Geophysics, Peking University, 100871 Beijing (China); Lin, Robert P.; Salem, Chadi; Pulupa, Marc; Larson, Davin E.; Luhmann, Janet G. [Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450 (United States); Yoon, Peter H., E-mail: wanglhwang@gmail.com [School of Space Research, Kyung Hee University, Yongin, Gyeonggi (Korea, Republic of)

    2012-07-01

    We present a statistical survey of {approx}2-20 keV superhalo electrons in the solar wind measured by the SupraThermal Electron instrument on board the two STEREO spacecraft during quiet-time periods from 2007 March through 2009 March at solar minimum. The observed superhalo electrons have a nearly isotropic angular distribution and a power-law spectrum, f{proportional_to}v{sup -{gamma}}, with {gamma} ranging from 5 to 8.7, with nearly half between 6.5 and 7.5, and an average index of 6.69 {+-} 0.90. The observed power-law spectrum varies significantly on a spatial scale of {approx}>0.1 AU and a temporal scale of {approx}>several days. The integrated density of quiet-time superhalo electrons at 2-20 keV ranges from {approx}10{sup -8} cm{sup -3} to 10{sup -6} cm{sup -3}, about 10{sup -9}-10{sup -6} of the solar wind density, and, as well as the power-law spectrum, shows no correlation with solar wind proton density, velocity, or temperature. The density of superhalo electrons appears to show a solar-cycle variation at solar minimum, while the power-law spectral index {gamma} has no solar-cycle variation. These quiet-time superhalo electrons are present even in the absence of any solar activity-e.g., active regions, flares or microflares, type III radio bursts, etc.-suggesting that they may be accelerated by processes such as resonant wave-particle interactions in the interplanetary medium, or possibly by nonthermal processes related to the acceleration of the solar wind such as nanoflares, or by acceleration at the CIR forward shocks.

  2. Multilayer optics for monochromatic high-resolution X-ray imaging diagnostic in a broad photon energy range from 2 keV to 22 keV

    Energy Technology Data Exchange (ETDEWEB)

    Troussel, Ph., E-mail: philippe.troussel@cea.fr [CEA, DAM, DIF, F-91297 Arpajon (France); Dennetiere, D. [Synchrotron Soleil, L’orme des Merisiers, 91190 Saint-Aubin (France); Maroni, R. [CEA, DAM, DIF, F-91297 Arpajon (France); Høghøj, P.; Hedacq, S. [Xenocs SA, 19, rue François Blumet, F-38360 Sassenage (France); Cibik, L.; Krumrey, M. [Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin (Germany)

    2014-12-11

    The “Commissariat à l’énergie atomique et aux énergies alternatives” (CEA) studies and designs advanced X-ray diagnostics to probe dense plasmas produced at the future Laser MegaJoule (LMJ) facility. Mainly for X-ray imaging with high spatial resolution, different types of multilayer mirrors were developed to provide broadband X-ray reflectance at grazing incidence. These coatings are deposited on two toroidal mirror substrates that are then mounted into a Wolter-type geometry (working at a grazing angle of 0.45°) to realize an X-ray microscope. Non-periodic (depth graded) W/Si multilayer can be used in the broad photon energy range from 2 keV to 22 keV. A third flat mirror can be added for the spectral selection of the microscope. This mirror is coated with a Mo/Si multilayer for which the d-spacing varies in the longitudinal direction to satisfy the Bragg condition within the angular acceptance of the microscope and also to compensate the angular dispersion due to the field of the microscope. We present a study of such a so-called Göbel mirror which was optimized for photon energy of 10.35 keV. The three mirrors were coated using magnetron sputtering technology by Xenocs SA. The reflectance in the entire photon energy range was determined in the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at the synchrotron radiation facility BESSY II in Berlin.

  3. FIRST INTEGRAL OBSERVATIONS OF V404 CYGNI DURING THE 2015 OUTBURST: SPECTRAL BEHAVIOR IN THE 20–650 KeV ENERGY RANGE

    Energy Technology Data Exchange (ETDEWEB)

    Roques, Jean-Pierre; Jourdain, Elisabeth [Université Toulouse, UPS-OMP, CNRS, IRAP, 9 Av. Roche, BP 44346, F-31028 Toulouse (France); Bazzano, Angela; Fiocchi, Mariateresa; Natalucci, Lorenzo; Ubertini, Pietro [Istituto di Astrofisica e Planetologia Spaziali, INAF, Via Fosso del Cavaliere 100, I-00133 Roma, Italy (Italy)

    2015-11-01

    In 2015 June, the source V404 Cygni (= GS2023+38) underwent an extraordinary outburst. We present the results obtained during the first revolution dedicated to this target by the INTEGRAL mission and focus on the spectral behavior in the hard X-ray domain, using both SPI and IBIS instruments. The source exhibits extreme variability and reaches fluxes of several tens of Crab. However, the emission between 20 and 650 keV can be understood in terms of two main components, varying on all the observable timescales, similar to what is observed in the persistent black hole system Cyg X-1. The low-energy component (up to ∼200 keV) presents a rather unusual shape, probably due to the intrinsic source variability. Nonetheless, a satisfactory description is obtained with a Comptonization model, if an unusually hot population of seed photons (kT{sub 0} ∼ 7 keV) is introduced. Above this first component, a clear excess extending up to 400–600 keV leads us to investigate a scenario where an additional (cutoff) power law could correspond to the contribution of the jet synchrotron emission, as proposed in Cyg X-1. A search for an annihilation feature did not provide any firm detection, with an upper limit of 2 × 10{sup −4} ph cm{sup −2} s{sup −1} (2σ) for a narrow line centered at 511 keV, on the averaged obtained spectrum.

  4. A balloon-borne instrument for high-resolution astrophysical spectroscopy in the 20-8000 keV energy range

    Science.gov (United States)

    Paciesas, W. S.; Baker, R.; Boclet, D.; Brown, S.; Cline, T.; Costlow, H.; Durouchoux, P.; Ehrmann, C.; Gehrels, N.; Hameury, J. M.

    1983-04-01

    The Low Energy Gamma ray Spectrometer (LEGS) is designed to perform fine energy resolution measurements of astrophysical sources. The instrument is configured for a particular balloon flight with either of two sets of high purity germanium detectors. In one configuration, the instrument uses an array of three coaxial detectors (effective volume equal to or approximately 230 cubic cm) inside an NaI (T1) shield and collimator (field of view equal to or approximately 16 deg FWHM) and operates in the 80 to 8000 keV energy range. In the other configuration, three planar detectors (effective area equal to or approximately square cm) surrounded by a combination of passive Fe and active NaI for shielding and collimation (field of view equal to or approximately 5 deg x 10 deg FWHM) are optimized for the 20 to 200 keV energy range. In a typical one day balloon flight, LEGS sensitivity limit (3 sigma) for narrow line features is less than or approximately .0008 ph/cm/s square (coaxial array: 80 to 2000 keV) and less than or approximately .0003 ph/square cm/s (planar array: 50 to 150 keV).

  5. Neutron Total Cross Sections of {sup 235}U From Transmission Measurements in the Energy Range 2 keV to 300 keV and Statistical Model Analysis of the Data

    Energy Technology Data Exchange (ETDEWEB)

    Derrien, H.; Harvey, J.A.; Larson, N.M.; Leal, L.C.; Wright, R.Q.

    2000-05-01

    The average {sup 235}U neutron total cross sections were obtained in the energy range 2 keV to 330 keV from high-resolution transmission measurements of a 0.033 atom/b sample.1 The experimental data were corrected for the contribution of isotope impurities and for resonance self-shielding effects in the sample. The results are in very good agreement with the experimental data of Poenitz et al.4 in the energy range 40 keV to 330 keV and are the only available accurate experimental data in the energy range 2 keV to 40 keV. ENDF/B-VI evaluated data are 1.7% larger. The SAMMY/FITACS code 2 was used for a statistical model analysis of the total cross section, selected fission cross sections and data in the energy range 2 keV to 200 keV. SAMMY/FITACS is an extended version of SAMMY which allows consistent analysis of the experimental data in the resolved and unresolved resonance region. The Reich-Moore resonance parameters were obtained 3 from a SAMMY Bayesian fits of high resolution experimental neutron transmission and partial cross section data below 2.25 keV, and the corresponding average parameters and covariance data were used in the present work as input for the statistical model analysis of the high energy range of the experimental data. The result of the analysis shows that the average resonance parameters obtained from the analysis of the unresolved resonance region are consistent with those obtained in the resolved energy region. Another important result is that ENDF/B-VI capture cross section could be too small by more than 10% in the energy range 10 keV to 200 keV.

  6. NEUTRON TOTAL CROSS SECTIONS OF 235U FROM TRANSMISSION MEASUREMENTS IN THE ENERGY RANGE 2 keV to 300 keV AND STATISTICAL MODEL ANALYSIS OF THE DATA

    Energy Technology Data Exchange (ETDEWEB)

    Derrien, H.

    2000-05-22

    The average {sup 235}U neutron total cross sections were obtained in the energy range 2 keV to 330 keV from high-resolution transmission measurements of a 0.033 atom/b sample. The experimental data were corrected for the contribution of isotope impurities and for resonance self-shielding effects in the sample. The results are in very good agreement with the experimental data of Poenitz et al. in the energy range 40 keV to 330 keV and are the only available accurate experimental data in the energy range 2 keV to 40 keV. ENDF/B-VI evaluated data are 1.7% larger. The SAMMY/FITACS code was used for a statistical model analysis of the total cross section, selected fission cross sections and {alpha} data in the energy range 2 keV to 200 keV. SAMMY/FITACS is an extended version of SAMMY which allows consistent analysis of the experimental data in the resolved and unresolved resonance region. The Reich-Moore resonance parameters were obtained from a SAMMY Bayesian fits of high resolution experimental neutron transmission and partial cross section data below 2.25 keV, and the corresponding average parameters and covariance data were used in the present work as input for the statistical model analysis of the high energy range of the experimental data. The result of the analysis shows that the average resonance parameters obtained from the analysis of the unresolved resonance region are consistent with those obtained in the resolved energy region. Another important result is that ENDF/B-VI capture cross section could be too small by more than 10% in the energy range 10 keV to 200 keV.

  7. First INTEGRAL Observations of V404 Cygni during the 2015 Outburst: Spectral Behavior in the 20-650 keV Energy Range

    Science.gov (United States)

    Roques, Jean-Pierre; Jourdain, Elisabeth; Bazzano, Angela; Fiocchi, Mariateresa; Natalucci, Lorenzo; Ubertini, Pietro

    2015-11-01

    In 2015 June, the source V404 Cygni (= GS2023+38) underwent an extraordinary outburst. We present the results obtained during the first revolution dedicated to this target by the INTEGRAL mission and focus on the spectral behavior in the hard X-ray domain, using both SPI and IBIS instruments. The source exhibits extreme variability and reaches fluxes of several tens of Crab. However, the emission between 20 and 650 keV can be understood in terms of two main components, varying on all the observable timescales, similar to what is observed in the persistent black hole system Cyg X-1. The low-energy component (up to ˜200 keV) presents a rather unusual shape, probably due to the intrinsic source variability. Nonetheless, a satisfactory description is obtained with a Comptonization model, if an unusually hot population of seed photons (kT0 ˜ 7 keV) is introduced. Above this first component, a clear excess extending up to 400-600 keV leads us to investigate a scenario where an additional (cutoff) power law could correspond to the contribution of the jet synchrotron emission, as proposed in Cyg X-1. A search for an annihilation feature did not provide any firm detection, with an upper limit of 2 × 10-4 ph cm-2 s-1 (2σ) for a narrow line centered at 511 keV, on the averaged obtained spectrum. Based on observations with INTEGRAL, an ESA project with instruments and science data center funded by ESA member states (especially the PI countries: Denmark, France, Germany, Italy, Spain, and Switzerland), Czech Republic, and Poland with the participation of Russia and USA.

  8. Neutron Resonance Parameters of 238U and the Calculated Cross Sections from the Reich-Moore Analysis of Experimental Data in the Neutron Energy Range from 0 keV to 20 keV

    Energy Technology Data Exchange (ETDEWEB)

    Derrien, H

    2005-12-05

    The neutron resonance parameters of {sup 238}U were obtained from a SAMMY analysis of high-resolution neutron transmission measurements and high-resolution capture cross section measurements performed at the Oak Ridge Electron Linear Accelerator (ORELA) in the years 1970-1990, and from more recent transmission and capture cross section measurements performed at the Geel Linear Accelerator (GELINA). Compared with previous evaluations, the energy range for this resonance analysis was extended from 10 to 20 keV, taking advantage of the high resolution of the most recent ORELA transmission measurements. The experimental database and the method of analysis are described in this report. The neutron transmissions and the capture cross sections calculated with the resonance parameters are compared with the experimental data. A description is given of the statistical properties of the resonance parameters and of the recommended values of the average parameters. The new evaluation results in a slight decrease of the effective capture resonance integral and improves the prediction of integral thermal benchmarks by 70 pcm to 200 pcm.

  9. First INTEGRAL observations of V404 Cygni during the 2015 outburst : spectral behavior in the 20 - 650 keV energy range

    CERN Document Server

    Roques, Jean-Pierre; Bazzano, Angela; Fiocchi, Mariateresa; Natalucci, Lorenzo; Ubertini, Pietro

    2015-01-01

    In June 2015, the source V404 Cygni (= GS2023+38) underwent an extraordinary outburst. We present the results obtained during the first revolution dedicated to this target by the INTEGRAL mission, and focus on the spectral behavior in the hard X-ray domain, using both SPI and IBIS instruments. The source exhibits extreme variability, and reaches fluxes of several tens of Crab. However, the emission between 20 and 650 keV can be understood in terms of two main components, varying on all the observable timescales, similar to what is observed in the persistent black hole system Cyg X-1. The low energy component (up to ~ 200 keV) presents a rather unusual shape, probably due to the intrinsic source variability. Nonetheless, a satisfactory description is obtained with a Comptonization model, if an unusually hot population of seed photons ($kT_0$ ~ 7 keV) is introduced. Above this first component, a clear excess extending up to 400-600 keV leads us to investigate a scenario where an additional (cutoff) power law co...

  10. Development of a soft x-ray diffractometer for a wideband multilayer grating with a novel layer structure in the 2-4 keV range

    Energy Technology Data Exchange (ETDEWEB)

    Imazono, Takashi; Koike, Masato; Kawachi, Tetsuya; Hasegawa, Noboru; Koeda, Masaru; Nagano, Tetsuya; Sasai, Hiroyuki; Oue, Yuki; Yonezawa, Zeno; Kuramoto, Satoshi; Terauchi, Masami; Takahashi, Hideyuki; Handa, Nobuo; Murano, Takanori [Quantum Beam Science Directorate, Japan Atomic Energy Agency, 8-1-7 Umemidai, Kizugawa, Kyoto 619-0215 (Japan); Device Dept., Shimadzu Corp., 1 Nishinokyo-Kuwabara-cho, Nakagyo-ku, Kyoto 604-8511 (Japan); IMRAM, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); ECBU, JEOL Ltd., 3-1-2 Musashino, Akishima, Tokyo 196-8558 (Japan)

    2012-07-11

    We have been developing a wavelength-dispersive soft x-ray spectrograph covering an energy region of 50-4000 eV to attach to a conventional electron microscope. Observation of soft x-ray emission in the 2-4 keV range needs a multilayer coated grating. In order to evaluate the performance of the optical component in the energy region, a goniometric apparatus has been newly developed and the preliminary performance has been tested using synchrotron radiation.

  11. Ranges, Reflection and Secondary Electron Emission for keV Hydrogen Ions Incident on Solid N2

    DEFF Research Database (Denmark)

    Børgesen, P.; Sørensen, H.; Hao-Ming, Chen

    1983-01-01

    Ranges were measured for 0.67–3.3 keV/amu hydrogen and deuterium ions in solid N2. Comparisons with similar results for N2-gas confirm the previously observed large phase effect in the stopping cross section. Measurements of the secondary electron emission coefficient for bulk solid N2 bombarded...... by 0.67–9 keV/amu ions also seem to support such a phase effect. It is argued that we may also extract information about the charge state of reflected projectiles....

  12. Single-crystal CVD diamond detector for low-energy charged particles with energies ranging from 100 keV to 2 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Yuki Sato; Hiroyuki Murakami [Nishina Center for Accelerator-Based Science, The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198, (Japan); Takehiro Shimaoka; Masakatsu Tsubota; Junichi, H. Kaneko [Graduate School of Engineering, Hokkaido University, N13, W8, Sapporo 060-8628, (Japan)

    2015-07-01

    The performance of a diamond detector made of a single-crystal diamond grown by chemical vapor deposition was studied for charged particles, having energies ranging from 100 keV to 2 MeV. Energy peaks of these low-energy ions were clearly observed. However, we observed that the pulse height for individual incident ion decreases with increasing atomic number of the ions. We estimated the charge collection efficiency of the generated charge carriers by charged particle incident. The charge collection above ∼95% is achieved for helium (He{sup +}) with the energy above 1.5 MeV. On the other hand, the charge collection efficiency for heavy-ions shows wrong values compared with that of He{sup +}, ∼70% for silicon (Si{sup +}) and 35 to 40% for gold (Au{sup 3+}), at the same incident energy range, respectively. (authors)

  13. Solar Wind ~20-300 keV Superhalo Electrons

    Science.gov (United States)

    Wang, L.; Yang, L.; He, J.; Tu, C. Y.; Pei, Z.

    2014-12-01

    High-energy superhalo electrons are present in the interplanetary medium even in absence of any solar activity, carrying important information on the electron acceleration in the solar wind. We present a statistical survey of ~20-300 keV superhalo electrons measured at 1 AU by the WIND 3DP instrument during quiet-time periods from 1995 January through 2013 December. The velocity distribution function of the observed quiet-time superhalo electrons generally fits to a power-law spectrum, f ~ v-γ, with γ ranging from ~4 to ~10. The integrated density of these superhalo electrons at 20-300 keV, nsup, ranges from 10-9 cm-3 to 10-5 cm-3. Both log(nsup) and γ show a good correlation with the sunspot number, with larger density and softer spectrum (γ~ 6-8) at solar maximum, and smaller density and harder spectrum (γ~ 4-5) at solar minimum. The observed power-law spectrum also has no clear association with flares, CMEs, active regions and solar wind core populations, while it shows a weak (~0.3) correlation with in situ solar wind turbulence spectrum. These results suggest that the seed particles of quiet-time superhalo electrons could originate from the Sun, and their acceleration could mainly occur in the interplanetary medium, probably by the electron interaction with solar wind turbulence, or by acceleration at the CIRs.

  14. Total electron scattering cross sections of molecules containing H, C, N, O and F in the energy range 0.2–6.0 keV

    Energy Technology Data Exchange (ETDEWEB)

    Gurung, Meera Devi; Ariyasinghe, W.M., E-mail: wickram_ariyasinghe@baylor.edu

    2017-03-15

    Based on the effective atomic total electron scattering cross sections (EATCS) of atoms in a molecular environment, a simple model is proposed to predict the total electron scattering cross sections (TCS) of H, C, N, O, and F containing molecules. The EATCS for these five atoms are reported for 0.2–6.0 keV energies. The predicted TCS by this model are compared with experimental TCS in the literature. The experimental TCS of CHF{sub 3}, C{sub 2}F{sub 4}, C{sub 2}F{sub 2}H{sub 2}, C{sub 4}F{sub 6}, and c-C{sub 4}F{sub 8} have been obtained for 0.2–4.5 keV electrons by measuring the attenuation of the electron beam through a gas cell.

  15. Total electron scattering cross sections of molecules containing H, C, N, O and F in the energy range 0.2-6.0 keV

    Science.gov (United States)

    Gurung, Meera Devi; Ariyasinghe, W. M.

    2017-03-01

    Based on the effective atomic total electron scattering cross sections (EATCS) of atoms in a molecular environment, a simple model is proposed to predict the total electron scattering cross sections (TCS) of H, C, N, O, and F containing molecules. The EATCS for these five atoms are reported for 0.2-6.0 keV energies. The predicted TCS by this model are compared with experimental TCS in the literature. The experimental TCS of CHF3, C2F4, C2F2H2, C4F6, and c-C4F8 have been obtained for 0.2-4.5 keV electrons by measuring the attenuation of the electron beam through a gas cell.

  16. The Hard X-ray 20-40 keV AGN Luminosity Function

    CERN Document Server

    Beckmann, V; Shrader, C R; Gehrels, N; Produit, N

    2006-01-01

    We have compiled a complete extragalactic sample based on 25,000 deg^2 to a limiting flux of 3E-11 ergs/cm**2/sec (7,000 deg^2 to a flux limit of 1E-11 ergs/cm**2/sec) in the 20 - 40 keV band with INTEGRAL. We have constructed a detailed exposure map to compensate for effects of non-uniform exposure. The flux-number relation is best described by a power-law with a slope of alpha = 1.66+-0.11. The integration of the cumulative flux per unit area leads to f = 2.6E-10 ergs/cm**2/sec/sr, which is about 1% of the known 20 - 40 keV X-ray background. We present the first luminosity function of AGNs in the 20-40 keV energy range, based on 38 extragalactic objects detected by the imager IBIS/ISGRI on-board INTEGRAL. The luminosity function shows a smoothly connected two power-law form, with an index of gamma_1 = 0.8 below, and gamma_2 = 2.1 above the turn-over luminosity of L* = 2.4E43 ergs/sec. The emissivity of all INTEGRAL AGNs per unit volume is W(> 1E41 ergs/sec) = 2.8E38 ergs/sec/Mpc**3. These results are consis...

  17. The Hard X-ray 20-40 keV AGN Luminosity Function

    Science.gov (United States)

    Beckmann, V.; Soldi, S.; Shrader, C. R.; Gehrels, N.; Produit, N.

    2006-01-01

    We have compiled a complete, significance limited extragalactic sample based on approximately 25,000 deg(sup 2) to a limiting flux of 3 x 10(exp -11) ergs per square centimeter per second. (approximately 7,000 deg(sup 2)) to a flux limit of 10(exp -11) ergs per square centimeter per second)) in the 20 - 40 keV band with INTEGRAL. We have constructed a detailed exposure map to compensate for effects of non-uniform exposure. The flux-number relation is best described by a power-law with a slope of alpha = 1.66 plus or minus 0.11. The integration of the cumulative flux per unit area leads to f(sub 20-40 keV) = 2.6 x 10(exp -10) ergs per square centimeter per second per sr(sup -1) which is about 1% of the known 20-40 keV X-ray background. We present the first luminosity function of AGN in the 20-40 keV energy range, based on 68 extragalactic objects detected by the imager IBIS/ISGRI on-board INTEGRAL. The luminosity function shows a smoothly connected two power-law form, with an index of gamma (sub 1) = 0.9 below, and gamma (sub 2) = 2.2 above the turn-over luminosity of L(sub *), = 4.6 x 10(sup 43) ergs per second. The emissivity of all INTEGRAL AGNs per unit volume is W(sub 20-40keV)(greater than 10(sup 41) ergs per second) = 2.8 x 10(sup 38) ergs per second h(sup 3)(sub 70) Mpc(sup -3). These results are consistent with those derived in the 2-20keV energy band and do not show a significant contribution by Compton-thick objects. Because the sample used in this study is truly local (z(raised bar) = 0.022)), only limited conclusions can be drawn for the evolution of AGNs in this energy band. But the objects explaining the peak in the cosmic X-ray background are likely to be either low luminosity AGN (L(sub x) less than 10(sup 41) ergs per second) or of other type, such as intermediate mass black holes, clusters, and star forming regions.

  18. The Range of 1-3 keV Electrons in Solid Oxygen and Carbon Monoxide

    DEFF Research Database (Denmark)

    Oehlenschlæger, M.; Andersen, H.H.; Schou, Jørgen

    1985-01-01

    The range of 1-3 keV electrons in films of solid oxygen and carbon monoxide has been measured by a mirror substrate method. The technique used here is identical to the one previously used for range measurements in solid hydrogen and nitrogen. The range in oxygen is slightly shorter than...... that in nitrogen whereas the range in carbon monoxide is about 20% larger than that in the nitrogen....

  19. Energy dependence of effective atomic numbers for photon energy absorption and photon interaction: Studies of some biological molecules in the energy range 1 keV-20 MeV

    DEFF Research Database (Denmark)

    Manohara, S.R.; Hanagodimath, S.M.; Gerward, Leif

    2008-01-01

    Effective atomic numbers for photon energy absorption, Z(PEA,eff), and for photon interaction, Z(PI,eff), have been calculated by a direct method in the photon-energy region from 1 keV to 20 MeV for biological molecules, such as fatty acids (lauric, myristic, palmitic, stearic, oleic, linoleic...... dependence of the mass attenuation coefficient, Z(PEA, eff), and the mass energy-absorption coefficient, Z(PI, eff), is shown graphically and in tabular form. Significant differences of 17%-38% between Z(PI, eff) and Z(PEA, eff) occur in the energy region 5-100 keV. The reasons for these differences...

  20. Angular distribution of ejected electrons from 20 keV He/sup +/ impact on He

    Energy Technology Data Exchange (ETDEWEB)

    Tokoro, N.; Takenouchi, S.; Urakawa, J.; Oda, N. (Tokyo Inst. of Tech. (Japan). Research Lab. of Nuclear Reactor)

    1982-10-28

    The angular distributions of ejected electrons in the energy range 5-70 eV have been measured at angles from 30 to 150/sup 0/ for 20 keV He/sup +/ impact on He. The angular dependence of excitation cross sections of autoionisation states 2s/sup 2/ /sup 1/S and 2p/sup 2/ /sup 1/D+2s2p /sup 1/P are in good agreement with previous data measured by Bordenave-Montesquieu et al (Phys. Rev.; A25:245 (1982)). The continuous parts of the electron spectra show symmetrical angular distributions around 90/sup 0/ in the laboratory frame for low-energy electrons (

  1. R-matrix analysis of {sup 235}U neutron transmission and cross sections in the energy range 0 to 2.25 keV

    Energy Technology Data Exchange (ETDEWEB)

    Leal, L.C.; Derrien, H.; Larson, N.M.; Wright, R.Q.

    1997-11-01

    This document describes a new R-matrix analysis of {sup 235}U cross section data in the energy range from 0 to 2,250 eV. The analysis was performed with the computer code SAMMY, that has recently been updated to permit, for the first time, inclusion of both differential and integral data within the analysis process. Fourteen differential data sets and six integral quantities were used in this evaluation: two measurements of fission plus capture, one of fission plus absorption, six of fission alone, two of transmission, and one of eta, plus standard values of thermal cross sections for fission, capture, and scattering, and of K1 and the Westcott g-factors for both fission and absorption. An excellent representation was obtained for the high-resolution transmission, fission, and capture cross-section data as well as for the integral quantities. The result is a single set of resonance parameters spanning the entire range up to 2,250 eV, a decided improvement over the present ENDF/VI evaluation, in which eleven discrete resonance parameter sets are required to cover that same energy range. This new evaluation is expected to greatly improve predictability of the criticality safety margins for nuclear systems in which {sup 235}U is present.

  2. SIMBOL-X, a new generation X-ray telescope for the 0.5-70 keV range

    CERN Document Server

    Ferrando, P

    2002-01-01

    SIMBOL-X is a high energy "mini" satellite class mission that is proposed by a French-Italian-English collaboration for a launch in 2009. SIMBOL-X is making use of a classical X-ray mirror, of ~ 600 cm2 maximum effective area, with a 30 m focal length in order to cover energies up to several tens of keV. This focal length will be achieved through the use of two spacecrafts in a formation flying configuration. This will give to SIMBOL-X unprecedented spatial resolution (20" HEW) and sensitivity in the hard X-ray range. By its coverage, from 0.5 to 70 keV, and sensitivity, SIMBOL-X will be an excellent instrument for the study of high energy processes in a large number of sources, as in particular accreting black-holes, extragalactic jets and AGNs.

  3. Measurement of the differential neutron-deuteron scattering cross section in the energy range from 100 keV to 600 keV using a proportional counter

    CERN Document Server

    Nolte, R; Plompen, A; Röttger, S

    2014-01-01

    The angular distribution of neutron-deuteron scattering was investigated using the proportional counter P2 simultaneously as scattering target and detector for the recoil deuterons. The measurements were carried out using monoenergetic neutrons in the energy range from 150 keV to 500 keV. Various techniques were employed to reduce distortions of the experimental pulse-height distribution by photon-induced events. The experimental data were compared with realistic simulations which were carried out using different evaluated data sets. This comparison allows to conclude on inconsistencies in the evaluations.

  4. Evaluation of Silicon Neutron Resonance Parameters in the Energy Range Thermal to 1800 keV

    Energy Technology Data Exchange (ETDEWEB)

    Derrien, H.

    2002-09-30

    The evaluation of the neutron cross sections of the three stable isotopes of silicon in the energy range thermal to 20 MeV was performed by Hetrick et al. for ENDF/B-VI (Evaluated Nuclear Data File). Resonance parameters were obtained in the energy range thermal to 1500 keV from a SAMMY analysis of the Oak Ridge National Laboratory experimental neutron transmission data. A new measurement of the capture cross section of natural silicon in the energy range 1 to 700 keV has recently been performed at the Oak Ridge Electron Linear Accelerator. Results of this measurement were used in a SAMMY reevaluation of the resonance parameters, allowing determination of the capture width of a large number of resonances. The experimental data base is described; properties of the resonance parameters are given. For the first time the direct neutron capture component has been taken into account from the calculation by Rauscher et al. in the energy range from thermal to 1 MeV. Results of benchmark calculations are also given. The new evaluation is available in the ENDF/B-VI format.

  5. Measurement of the Np237(n,γ) cross section from 20 meV to 500 keV with a high efficiency, highly segmented 4π BaF2 detector

    Science.gov (United States)

    Esch, E.-I.; Reifarth, R.; Bond, E. M.; Bredeweg, T. A.; Couture, A.; Glover, S. E.; Greife, U.; Haight, R. C.; Hatarik, A. M.; Hatarik, R.; Jandel, M.; Kawano, T.; Mertz, A.; O'Donnell, J. M.; Rundberg, R. S.; Schwantes, J. M.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.

    2008-03-01

    The Np237(n,γ)Np238 cross section has been measured in the neutron energy range from 20 meV to 500 keV using the DANCE array at the Los Alamos National Laboratory. This new facility allows experiments with submilligram samples and is therefore well suited to investigate isotopes with half-lives as low as a few hundred days. In this benchmark measurement, only 0.42 mg of Np237 was sufficient to determine differential cross sections relative to the well-known resonance at 0.5 eV. The thermal cross section was measured to σ2200m/s=177±5 barn, σkT=25.3meV=167±4 barn and the resonance integral to RI=693±6 barn.

  6. Calibration of semiconductor detectors in the 200-8500 keV range at VNIIM.

    Science.gov (United States)

    Tereshchenko, Evgeny E; Moiseev, Nikolay

    2012-09-01

    At the ionising radiation department of the D.I. Mendeleyev Institute for Metrology, a semiconductor detector was calibrated in the energy range 200-8500 keV using (n,2γ) and (n,γ) reactions. Separate cylindrical targets (77 mm diameter and 10mm height) were made from mercuric sulphate, sodium chloride and metallic titanium. A (252)Cf spontaneous fission neutron source, placed in 150 mm diameter polyethylene ball, was used to generate thermal neutrons. The optimal target dimensions were determined taking into account the thermal neutron cross-sections and gamma-radiation attenuations in the target materials. The influence of the background radiation induced by neutrons from the walls, floors and ceilings was also taken into account. The shapes of the efficiency curves for point and volume sources in the 200-8500 keV range have been investigated. The experimental results are in good agreement with Monte-Carlo calculations. The emission rate of the 6.13 MeV photons from a (238)Pu-(13)C source was determined with an expanded uncertainty, U(c), of 10% (k=2).

  7. Cluster effect on projected range of 30 keV C{sub 60}{sup +} in silicon

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Y.; Nakajima, K.; Suzuki, M. [Department of Micro Engineering, Kyoto University, Kyoto 606-8501 (Japan); Narumi, K.; Saitoh, Y. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gumma 370-1292 (Japan); Vandervorst, W. [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Kimura, K., E-mail: kimura@kues.kyoto-u.ac.jp [Department of Micro Engineering, Kyoto University, Kyoto 606-8501 (Japan)

    2011-10-01

    Pre-amorphized silicon wafers are implanted with 30 keV C{sub 60}{sup +} and 0.5 keV C{sup +} ions at room temperature with fluences about 2 x 10{sup 15} atoms/cm{sup 2}. The depth profiles of implanted carbon are measured using high-resolution Rutherford backscattering spectroscopy. The observed average depth of C for the C{sub 60}{sup +} implantation is 6.1 nm while that for the C{sup +} implantation is 4.0 nm, showing a large cluster effect on the projected range.

  8. Differential elastic and inelastic cross sections in 1. 5 <= E/sub 0/ <= 25 keV He/sup +/-H collisions at scattering angles thetasub(lab) ranging from 5' to 2/sup 0/

    Energy Technology Data Exchange (ETDEWEB)

    Bordenave-Montesquieu, D.; Nouet, P.; Boutonnet, A.; Bergnes, C.; Dagnac, R.

    1987-09-14

    Elastic and inelastic cross sections, differential in energy loss and scattering angle, have been determined from the energy loss spectra of 1.5 - 25 keV He/sup +/ scattered from atomic hydrogen at scattering angles from 5'-2/sup 0/ (laboratory frame). The experimental results compare favourably with the experimental and theoretical data obtained at low incident energies by other authors, but for the higher energies, the present results exhibit a strong disagreement with many of the reported calculations.

  9. Effective atomic numbers and electron densities of bacteriorhodopsin and its comprising amino acids in the energy range 1 keV-100 GeV

    Science.gov (United States)

    Ahmadi, Morteza; Lunscher, Nolan; Yeow, John T. W.

    2013-04-01

    Recently, there has been an interest in fabrication of X-ray sensors based on bacteriorhodopsin, a proton pump protein in cell membrane of Halobacterium salinarium. Therefore, a better understanding of interaction of X-ray photons with bacteriorhodopsin is required. We use WinXCom program to calculate the mass attenuation coefficient of bacteriorhodopsin and its comprising amino acids for photon energies from 1 keV to 100 GeV. These amino acids include alanine, arginine, asparagine, aspartic acid, glutamine, glutamic acid, glycine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, valine, Asx1, Asx2, Glx1 and Glx2. We then use that data to calculate effective atomic number and electron densities for the same range of energy. We also emphasize on two ranges of energies (10-200 keV and 1-20 MeV) in which X-ray imaging and radiotherapy machines work.

  10. Group delay dispersion measurements in the mid-infrared spectral range of 2-20 µm.

    Science.gov (United States)

    Habel, Florian; Trubetskov, Michael; Pervak, Vladimir

    2016-07-25

    We present two measurement devices which both allow the direct measurement of the group delay (GD) and group delay dispersion (GDD) of laser optics, covering the near- and mid-infrared (MIR) spectral range from 2 to 20 µm (500-5,000 cm-1). Two different kinds of devices were developed to measure the GDD of multilayer interference coatings. One is a resonant scanning interferometer (RSI) and the other is a white light interferometer (WLI). The WLI is also capable of measuring the GDD in transmission, for instance of bulk material. GDD measurements of a high dispersive mirror for wavelengths from 2.0 to 2.15 µm and one of a multilayer mirror from 8.5 to 12.0 µm are presented. A measurement of a zinc selenide (ZnSe) substrate in transmission was made with the WLI demonstrating the full bandwidth of the device from 1.9 to 20 µm. The comparison of all measurements with their related theoretical values shows a remarkable correspondence.

  11. High resolution spectrometer for extended x-ray absorption fine structure measurements in the 6 keV to 15 keV energy range

    Science.gov (United States)

    Seely, J. F.; Hudson, L. T.; Henins, Albert; Feldman, U.

    2016-11-01

    A Cauchois transmission-crystal spectrometer has been developed with high crystal resolving power in the 6 keV-15 keV energy range and sufficient sensitivity to record single-shot spectra from the Lawrence Livermore National Laboratory (LLNL) Titan laser and other comparable or more energetic lasers. The spectrometer capabilities were tested by recording the W L transitions from a laboratory source and the extended x-ray absorption fine structure (EXAFS) spectrum through a Cu foil.

  12. Luminescent collisions of He+ and He++ ions with H2 molecules at energies below 2 keV

    Science.gov (United States)

    Pranszke, B.; Werbowy, S.; Miotk, R.; Borkowski, K. J.; Kowalski, A.

    2013-10-01

    Spectroscopic studies of collisions between He+ and He++ ions with H2 gas target have been performed in the 200-600 nm wavelength range. Atomic lines of hydrogen Balmer series and several helium lines were identified and their excitation functions between 50 eV and 1 keV (2 keV for He++) were determined.

  13. Single-electron capture for 2-8 keV incident energy and direct scattering at 6 keV in He[sup 2+]-He collisions

    Energy Technology Data Exchange (ETDEWEB)

    Bordenave-Montesquieu, D.; Dagnac, R. (Toulouse-3 Univ., 31 (France). Centre de Physique Atomique)

    1992-06-14

    We studied the single-electron capture as well as the direct processes occurring when a He[sup 2+] ion is scattered by a He target. Doubly differential cross sections were measured for single-electron capture with a collision energy ranging from 2 to 8 keV and a scattering angle varying from 10' to 3[sup o]30' (laboratory frame). Single-electron capture into excited states of He[sup +] was found to be the dominant process, confirming a previous experimental study. Elastic scattering and ionization differential cross sections were measured for E = 6 keV. (Author).

  14. New electron source concept for single-shot sub-100 fs electron diffraction in the 100 keV range

    CERN Document Server

    van Oudheusden, T; Siwick, B J; Van der Geer, S B; Root, W P E M O; Luiten, O J

    2007-01-01

    We present a method for producing sub-100 fs electron bunches that are suitable for single-shot ultrafast electron diffraction experiments in the 100 keV energy range. A combination of analytical results and state-of-the-art numerical simulations show that it is possible to create 100 keV, 0.1 pC, 20 fs electron bunches with a spotsize smaller than 500 micron and a transverse coherence length of 3 nm, using established technologies in a table-top set-up. The system operates in the space-charge dominated regime to produce energy-correlated bunches that are recompressed by established radio-frequency techniques. With this approach we overcome the Coulomb expansion of the bunch, providing an entirely new ultrafast electron diffraction source concept.

  15. Calculations of stopping powers and inelastic mean free paths for 20 eV-20 keV electrons in 11 types of human tissue.

    Science.gov (United States)

    Tan, Zhenyu; Liu, Wei

    2013-12-01

    Systematic calculations are performed for determining the stopping powers (SP) and inelastic mean free paths (IMFP) for 20 eV-20 keV electrons in 11 types of human tissue. The calculations are based on a dielectric model, including the Born-Ochkur exchange correction. The optical energy loss functions (OELF) are empirically evaluated, because of the lack of available experimental optical data for the 11 tissues under consideration. The evaluated OELFs are examined by the f-sum rule expected from the dielectric response theory, and by calculation of the mean excitation energy. The calculated SPs are compared with those for PMMA (polymethylmethacrylate, a tissue equivalent material) and liquid water. The SP and IMFP data presented here are the results for the 11 human tissues over the energy range of 20 eV-20 keV, and are of importance in radiotherapy planning and for studies of various radiation effects on human tissues.

  16. Emission lines between 1 and 2 keV in Cometary X-ray Spectra

    CERN Document Server

    Ewing, Ian; Bodewits, Dennis; Dennerl, Konrad; Lisse, Carey M; Wolk, Scott J

    2012-01-01

    We present the detection of new cometary X-ray emission lines in the 1.0 to 2.0 keV range using a sample of comets observed with the Chandra X-ray observatory and ACIS spectrometer. We have selected 5 comets from the Chandra sample with good signal-to-noise spectra. The surveyed comets are: C/1999 S4 (LINEAR), C/1999 T1 (McNaught-Hartley), 153P/2002 (Ikeya-Zhang), 2P/2003 (Encke), and C/2008 8P (Tuttle). We modeled the spectra with an extended version of our solar wind charge exchange (SWCX) emission model (Bodewits et al. 2007). Above 1 keV, we find Ikeya-Zhang to have strong emission lines at 1340 and 1850 eV that we identify as being created by solar wind charge exchange lines of Mg XI and Si XIII, respectively, and weaker emission lines at 1470, 1600, and 1950 eV formed by SWCX of Mg XII, Mg XI, and Si XIV, respectively. The Mg XI and XII and Si XIII and XIV lines are detected at a significant level for the other comets in our sample (LS4, MH, Encke, 8P), and these lines promise additional diagnostics to ...

  17. Preparation for B4C/Mo2C multilayer deposition of alternate multilayer gratings with high efficiency in the 0.5-2.5 keV energy range

    Science.gov (United States)

    Choueikani, Fadi; Delmotte, Franck; Bridou, Françoise; Lagarde, Bruno; Mercere, Pascal; Otero, Edwige; Ohresser, Philippe; Polack, François

    2013-03-01

    This paper presents a study of B4C/Mo2C multilayers mirrors with the aim of using it in the achievement of Alternate MultiLayer (AML) grating. Such component allows a high efficiency in the 500-2500 eV energy range for the DEIMOS beamline. Multilayers were deposited on silicon substrate. They are characterized by reflectometry under grazing incidence. Numerical adjustments were performed with a model of two layers in the period without any interfacial. A prototype of AML grating was fabricated and characterized. The efficiency of the first order of diffraction was worth 15% at 1700 eV.

  18. A low background-rate detector for ions in the 5 to 50 keV energy range to be used for radioisotope dating with a small cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, P.G.

    1986-11-25

    Accelerator mass spectrometry in tandem Van de Graaff accelerators has proven successful for radioisotope dating small samples. We are developing a 20 cm diameter 30 to 40 keV cyclotron dedicated to high-sensitivity radioisotope dating, initially for /sup 14/C. At this energy, range and dE/dx methods of particle identification are impossible. Thus arises the difficult problem of reliably detecting 30 to 40 keV /sup 14/C at 10/sup -2/ counts/sec in the high background environment of the cyclotron, where lower energy ions, electrons, and photons bombard the detector at much higher rates. We have developed and tested an inexpensive, generally useful ion detector that allows dark-count rates below 10/sup -4/ counts/sec and excellent background suppression. With the cyclotron tuned near the /sup 13/CH background peak, to the frequency for /sup 14/C, the detector suppresses the background to 6 x 10/sup -4/ counts/sec. For each /sup 14/C ion the detectors grazing-incidence Al/sub 2/O/sub 3/ conversion dynode emits about 20 secondary electrons, which are independently multiplied in separate pores of a microchannel plate. The output signal is proportional to the number of secondary electrons, allowing pulse-height discrimination of background. We have successfully tested the detector with positive /sup 12/C, /sup 23/Na, /sup 39/K, /sup 41/K, /sup 85/Rb, /sup 87/Rb, and /sup 133/Cs at 5 to 40 keV, and with 36 keV negative /sup 12/C and /sup 13/CH. It should detect ions and neutrals of all species, at energies above 5 keV, with good efficiency and excellent background discrimination. Counting efficiency and background discrimination improve with higher ion energy. The detector can be operated at least up to 2 x 10/sup -7/ Torr and be repeatedly exposed to air. The maximum rate is 10/sup 6.4/ ions/sec in pulse counting mode and 10/sup 9.7/ ions/sec in current integrating mode.

  19. Sputtering and surface structure modification of gold thin films deposited onto silicon substrates under the impact of 20–160 keV Ar{sup +} ions

    Energy Technology Data Exchange (ETDEWEB)

    Mammeri, S., E-mail: smammeri@yahoo.fr [Centre de Recherche Nucléaire d’Alger, B.P. 399, 02 Bd. Frantz Fanon, Alger-Gare, Algiers (Algeria); Ouichaoui, S. [Université des Sciences et de la Technologie H. Boumediene (USTHB), Faculté de Physique, Laboratoire SNIRM, B.P. 32, El-Alia, 16111 Bab Ezzouar, Algiers (Algeria); Ammi, H.; Dib, A. [Centre de Recherche Nucléaire d’Alger, B.P. 399, 02 Bd. Frantz Fanon, Alger-Gare, Algiers (Algeria)

    2014-10-15

    Highlights: •Sputter yields were measured for gold thin films under keV Ar{sup +} ion bombardment. •RBS analysis was used to derive energy dependence of sputtering yield. •Surface effects under Ar{sup +} ion irradiation were studied by SEM and XRD analyses. -- Abstract: The induced sputtering and surface state modification of Au thin films bombarded by swift Ar{sup +} ions under normal incident angle have been studied over an energy range of (20–160) keV using three complementary techniques: Rutherford backscattering spectroscopy (RBS), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The sputtering yields determined by RBS measurements using a 2 MeV {sup 4}He{sup +} ion beam were found to be consistent with previous data measured within the Ar{sup +} ion energy region E ⩽ 50 keV, which are thus extended to higher bombarding energies. Besides, the SEM and XRD measurements clearly point out that the irradiated Au film surfaces undergo drastic modifications with increasing the Ar{sup +} ion energy, giving rise to the formation of increasingly sized grains of preferred (1 1 1) crystalline orientations. The relevance of different sputtering yield models for describing experimental data is discussed with invoking the observed surface effects induced by the Ar{sup +} ion irradiation.

  20. Contrasting physics in wire array z pinch sources of 1-20 keV emission on the Z facilitya)

    Science.gov (United States)

    Ampleford, D. J.; Jones, B.; Jennings, C. A.; Hansen, S. B.; Cuneo, M. E.; Harvey-Thompson, A. J.; Rochau, G. A.; Coverdale, C. A.; Laspe, A. R.; Flanagan, T. M.; Moore, N. W.; Sinars, D. B.; Lamppa, D. C.; Harding, E. C.; Thornhill, J. W.; Giuliani, J. L.; Chong, Y.-K.; Apruzese, J. P.; Velikovich, A. L.; Dasgupta, A.; Ouart, N.; Sygar, W. A.; Savage, M. E.; Moore, J. K.; Focia, R.; Wagoner, T. C.; Killebrew, K. L.; Edens, A. D.; Dunham, G. S.; Jones, M. C.; Lake, P. W.; Nielsen, D. S.; Wu, M.; Carlson, A. L.; Kernahan, M. D.; Ball, C. R.; Scharberg, R. D.; Mulville, T. D.; Breden, E. W.; Speas, C. S.; Olivas, G.; Sullivan, M. A.; York, A. J.; Justus, D. W.; Cisneros, J. C.; Strizic, T.; Reneker, J.; Cleveland, M.; Vigil, M. P.; Robertson, G.; Sandoval, D.; Cox, C.; Maurer, A. J.; Graham, D. A.; Huynh, N. B.; Toledo, S.; Molina, L. P.; Lopez, M. R.; Long, F. W.; McKee, G. R.; Porter, J. L.; Herrmann, M. C.

    2014-05-01

    Imploding wire arrays on the 20 MA Z generator have recently provided some of the most powerful and energetic laboratory sources of multi-keV photons, including ∼375 kJ of Al K-shell emission (hν ∼ 1-2 keV), ∼80 kJ of stainless steel K-shell emission (hν ∼ 5-9 keV) and a kJ-level of Mo K-shell emission (hν ∼ 17 keV). While the global implosion dynamics of these different wire arrays are very similar, the physical process that dominates the emission from these x-ray sources fall into three broad categories. Al wire arrays produce a column of plasma with densities up to ∼3 × 1021 ions/cm3, where opacity inhibits the escape of K-shell photons. Significant structure from instabilities can reduce the density and increase the surface area, therefore increase the K-shell emission. In contrast, stainless steel wire arrays operate in a regime where achieving a high pinch temperature (achieved by thermalizing a high implosion kinetic energy) is critical and, while opacity is present, it has less impact on the pinch emissivity. At higher photon energies, line emission associated with inner shell ionization due to energetic electrons becomes important.

  1. Simultaneous solution of Kompaneets equation and Radiative Transfer equation in the photon energy range 1 - 125 KeV

    CERN Document Server

    Peraiah, A; varghese, B A

    2010-01-01

    Radiative transfer equation in plane parallel geometry and Kompaneets equation is solved simultaneously to obtain theoretical spectrum of 1-125 KeV photon energy range. Diffuse radiation field is calculated using time-independent radiative transfer equation in plane parallel geometry, which is developed using discrete space theory (DST) of radiative transfer in a homogeneous medium for different optical depths. We assumed free-free emission and absorption and emission due to electron gas to be operating in the medium. The three terms $n, n^2$ and $\\displaystyle \\bigg({\\frac {\\partial n}{\\partial x_k}}\\bigg)$ where $n$ is photon phase density and $\\displaystyle x_k= \\bigg({\\frac {h \

  2. A comparative study of inelastic scattering models at energy levels ranging from 0.5 keV to 10 keV

    Science.gov (United States)

    Hu, Chia-Yu; Lin, Chun-Hung

    2017-03-01

    Six models, including a single-scattering model, four hybrid models, and one dielectric function model, were evaluated using Monte Carlo simulations for aluminum and copper at incident beam energies ranging from 0.5 keV to 10 keV. The inelastic mean free path, mean energy loss per unit path length, and backscattering coefficients obtained by these models are compared and discussed to understand the merits of the various models. ANOVA (analysis of variance) statistical models were used to quantify the effects of inelastic cross section and energy loss models on the basis of the simulated results deviation from the experimental data for the inelastic mean free path, the mean energy loss per unit path length, and the backscattering coefficient, as well as their correlations. This work in this study is believed to be the first application of ANOVA models towards evaluating inelastic electron beam scattering models. This approach is an improvement over the traditional approach which involves only visual estimation of the difference between the experimental data and simulated results. The data suggests that the optimization of the effective electron number per atom, binding energy, and cut-off energy of an inelastic model for different materials at different beam energies is more important than the selection of inelastic models for Monte Carlo electron scattering simulation. During the simulations, parameters in the equations should be tuned according to different materials for different beam energies rather than merely employing default parameters for an arbitrary material. Energy loss models and cross-section formulas are not the main factors influencing energy loss. Comparison of the deviation of the simulated results from the experimental data shows a significant correlation (p secondary electrons for backscattering coefficient simulation is recommended for elements with high atomic numbers. In hybrid models, introducing the inner shell ionization model improves the

  3. STABILITY OF EXTRATERRESTRIAL GLYCINE UNDER ENERGETIC PARTICLE RADIATION ESTIMATED FROM 2 keV ELECTRON BOMBARDMENT EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Maté, B.; Tanarro, I.; Escribano, R.; Moreno, M. A.; Herrero, V. J. [Instituto de Estructura de la Materia (IEM-CSIC), Serrano 123, E-28006 Madrid (Spain)

    2015-06-20

    The destruction of solid glycine under irradiation with 2 keV electrons has been investigated by means of IR spectroscopy. Destruction cross sections, radiolysis yields, and half-life doses were determined for samples at 20, 40, 90, and 300 K. The thickness of the irradiated samples was kept below the estimated penetration depth of the electrons. No significant differences were obtained in the experiments below 90 K, but the destruction cross section at 300 K was larger by a factor of 2. The radiolysis yields and half-life doses are in good accordance with recent MeV proton experiments, which confirms that electrons in the keV range can be used to simulate the effects of cosmic rays if the whole sample is effectively irradiated. In the low temperature experiments, electron irradiation leads to the formation of residues. IR absorptions of these residues are assigned to the presence CO{sub 2}, CO, OCN{sup −}, and CN{sup −} and possibly to amide bands I to III. The protection of glycine by water ice is also studied. A water ice film of ∼150 nm is found to provide efficient shielding against the bombardment of 2 keV electrons. The results of this study show also that current Monte Carlo predictions provide a good global description of electron penetration depths. The lifetimes estimated in this work for various environments ranging from the diffuse interstellar medium to the inner solar system, show that the survival of hypothetical primeval glycine from the solar nebula in present solar system bodies is not very likely.

  4. A comparative study of inelastic scattering models at energy levels ranging from 0.5 keV to 10 keV

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Chia-Yu [Department of Photonics, National Cheng Kung University, Tainan 701, Taiwan (China); Lin, Chun-Hung, E-mail: chlin@mail.ncku.edu.tw [Department of Photonics, National Cheng Kung University, Tainan 701, Taiwan (China); Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan (China)

    2017-03-01

    Six models, including a single-scattering model, four hybrid models, and one dielectric function model, were evaluated using Monte Carlo simulations for aluminum and copper at incident beam energies ranging from 0.5 keV to 10 keV. The inelastic mean free path, mean energy loss per unit path length, and backscattering coefficients obtained by these models are compared and discussed to understand the merits of the various models. ANOVA (analysis of variance) statistical models were used to quantify the effects of inelastic cross section and energy loss models on the basis of the simulated results deviation from the experimental data for the inelastic mean free path, the mean energy loss per unit path length, and the backscattering coefficient, as well as their correlations. This work in this study is believed to be the first application of ANOVA models towards evaluating inelastic electron beam scattering models. This approach is an improvement over the traditional approach which involves only visual estimation of the difference between the experimental data and simulated results. The data suggests that the optimization of the effective electron number per atom, binding energy, and cut-off energy of an inelastic model for different materials at different beam energies is more important than the selection of inelastic models for Monte Carlo electron scattering simulation. During the simulations, parameters in the equations should be tuned according to different materials for different beam energies rather than merely employing default parameters for an arbitrary material. Energy loss models and cross-section formulas are not the main factors influencing energy loss. Comparison of the deviation of the simulated results from the experimental data shows a significant correlation (p < 0.05) between the backscattering coefficient and energy loss per unit path length. The inclusion of backscattering electrons generated by both primary and secondary electrons for

  5. Evaluation of n + /sup 242/Pu reactions from 10 keV to 20 MeV. [Total cross sections, neutron emission energy dependence

    Energy Technology Data Exchange (ETDEWEB)

    Madland, D.G.; Young, P.G.

    1978-10-01

    An evaluation of the n + /sup 242/Pu cross sections is presented for the neutron energy range of 10 keV to 20 MeV. The total fission and radiative capture cross sections are based upon experimental measurements on /sup 242/Pu. The remaining cross sections, together with the elastic and inelastic angular distributions to low-lying states, were calculated using various reaction models. An expression is presented for the energy dependence of the average number of neutrons produced per fission. The results were placed in ENDF/B-V format and combined with a recent evaluation of data below 10 keV by the Hanford Engineering Development Laboratory, so that a complete data set covering the energy range of 10/sup -5/ eV to 20 MeV is available. 41 references. (JFP)

  6. Design of a single moderator-type neutron spectrometer with enhanced energy resolution in the energy range from a few to 100 keV

    Energy Technology Data Exchange (ETDEWEB)

    Tanimura, Y. [Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan)]. E-mail: tanimura@popsvr.tokai.jaeri.go.jp; Saegusa, J. [Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Yoshizawa, M. [Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Yoshida, M. [Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan)

    2005-08-01

    The moderator structure for a neutron spectrometer was optimized with the Monte Carlo code MCNP-4B. The spectrometer consists of a cylindrical moderator and a position-sensitive thermal neutron detector and obtains energy spectra from thermal neutron distribution along its cylindrical axis. The structure of the moderator was improved by using a low hydrogen density material on one end and a high hydrogen density on the other, and inserting a neutron absorber that eliminates thermal neutron diffusion. This design improves the energy resolution of the spectrometer, especially for low-energy neutrons from a few to 100 keV. The designed spectrometer can be applied to the measurement of energy spectra over a neutron energy range from a few keV to 20 MeV.

  7. Attenuation coefficients for fibrous self-compacting concrete in the energy range of 50-3000 keV

    Energy Technology Data Exchange (ETDEWEB)

    Bento, W.V.; Magalhaes, L.A.M.; Conti, C.C., E-mail: ccconti@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-04-01

    The fibrous self-compacting concrete is a high performance concrete with uniformly distributed iron fibers. Transmission measurements, with {sup 137}Cs and {sup 60}Co sources were performed for the attenuation coefficients determination for both ordinary and fibrous self-compacting concretes. The results were compared to each other and to the values found in the literature for ordinary concrete. The mass attenuation coefficient for the fibrous self-compacting concrete showed to be higher than those for ordinary concrete of about 5%, depending on the gamma energy. However, it should be noted that the density of fibrous self-compacting concrete is higher than ordinary concrete, 2.4 g/cm{sup 3} and 1.9 g/cm{sup 3} respectively, increasing still further the difference in mass attenuation coefficient. In addition to that, by using Monte Carlo simulations, with MCNP5 Monte Carlo computer code, the data was extended to the 50-3000 keV gamma energy range. (author)

  8. Development of a flat-field spectrometer with a wideband Ni/C multilayer grating in the 1–3.5 keV range

    Energy Technology Data Exchange (ETDEWEB)

    Imazono, Takashi [Quantum Beam Science Center, Japan Atomic Energy Agency, 8-1-7, Umemidai, Kizugawa, Kyoto 619-0216 (Japan)

    2016-07-27

    To develop a flat-field spectrometer with coverage of the 1–3.5 keV range, a wideband Ni/C multilayer grating was invented. The multilayer consists of two kinds of layer structures. One is a conventional periodic multilayer of thickness D{sub 1} = 5.6 nm, Ni thickness ratio to the multilayer period γ{sub 1} = 0.5 and the number of layers N{sub 1} = 79. Both the first and last layers are Ni. The other is a C/Ni bilayer of D{sub 2} = 8.4 nm, γ{sub 2} = 0.53 and N{sub 2} = 2. The first layer is C and then Ni. The aperiodic multilayer from the topmost C/Ni bilayer was coated on a laminar-type grating having an effective grating constant of 1/2400 mm, groove depth of 2.8 nm, and duty ratio (land width/groove period) of 0.5. In a preliminary experiment, the diffraction efficiency was in excess of 0.8% in the energy range of 2.1-3.3 keV and the maximum of 5.4% at 3.1 keV at a constant angle of incidence of 88.54°, which is considerably higher than that of an Au-coated grating before deposition of the multilayer.

  9. Range Measurements of keV Hydrogen Ions in Solid Oxygen and Carbon Monoxide

    DEFF Research Database (Denmark)

    Schou, Jørgen; Sørensen, H.; Andersen, H.H.

    1984-01-01

    Ranges of 1.3–3.5 keV/atom hydrogen and deuterium molecular ions have been measured by a thin-film reflection method. The technique, used here for range measurements in solid oxygen and carbon monoxide targets, is identical to the one used previously for range measurements in hydrogen and nitrogen....... The main aim was to look for phase-effects, i.e. gas-solid differences in the stopping processes. While measured ranges in solid oxygen were in agreement with known gas data, the ranges in solid carbon monoxide were up to 50% larger than those calculated from gas-stopping data. The latter result agrees...

  10. An X-ray Raman spectrometer for EXAFS studies on minerals: bent Laue spectrometer with 20 keV X-rays.

    Science.gov (United States)

    Hiraoka, N; Fukui, H; Tanida, H; Toyokawa, H; Cai, Y Q; Tsuei, K D

    2013-03-01

    An X-ray Raman spectrometer for studies of local structures in minerals is discussed. Contrary to widely adopted back-scattering spectrometers using ≤10 keV X-rays, a spectrometer utilizing ~20 keV X-rays and a bent Laue analyzer is proposed. The 20 keV photons penetrate mineral samples much more deeply than 10 keV photons, so that high intensity is obtained owing to an enhancement of the scattering volume. Furthermore, a bent Laue analyzer provides a wide band-pass and a high reflectivity, leading to a much enhanced integrated intensity. A prototype spectrometer has been constructed and performance tests carried out. The oxygen K-edge in SiO(2) glass and crystal (α-quartz) has been measured with energy resolutions of 4 eV (EXAFS mode) and 1.3 eV (XANES mode). Unlike methods previously adopted, it is proposed to determine the pre-edge curve based on a theoretical Compton profile and a Monte Carlo multiple-scattering simulation before extracting EXAFS features. It is shown that the obtained EXAFS features are reproduced fairly well by a cluster model with a minimal set of fitting parameters. The spectrometer and the data processing proposed here are readily applicable to high-pressure studies.

  11. DNA strand breaks and crosslinks induced by transient anions in the range 2-20 eV

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Xinglan; Zheng, Yi, E-mail: Yizheng@fzu.edu.cn [Research Institute of Photocatalysis, State Key Laboratory of Photocatalysis on Energy and Environment, Fuzhou University, Fuzhou 350002 (China); Sanche, Léon [Group in the Radiation Sciences, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4 (Canada)

    2014-04-21

    The energy dependence of the yields of single and double strand breaks (SSB and DSB) and crosslinks induced by electron impact on plasmid DNA films is measured in the 2-20 eV range. The yield functions exhibit two strong maxima, which are interpreted to result from the formation of core-excited resonances (i.e., transient anions) of the bases, and their decay into the autoionization channel, resulting in π → π{sup *} electronic transitions of the bases followed by electron transfer to the C–O σ{sup *} bond in the phosphate group. Occupancy of the σ{sup *} orbital ruptures the C–O bond of the backbone via dissociative electron attachment, producing a SSB. From a comparison of our results with those of other works, including theoretical calculations and electron-energy-loss spectra of the bases, the 4.6 eV peak in the SSB yield function is attributed to the resonance decay into the lowest electronically excited states of the bases; in particular, those resulting from the transitions 1{sup 3}A{sup ′} (π{sub 2} → π{sub 3}{sup *}) and 1{sup 3}A{sup ″} (n{sub 2} → π{sub 3}{sup *}) of thymine and 1{sup 3}A{sup ′} (π → π{sup *}) of cytosine. The strongest peak at 9.6 eV in the SSB yield function is also associated with electron captured by excited states of the bases, resulting mostly from a multitude of higher-energy π → π{sup *} transitions. The DSB yield function exhibits strong maxima at 6.1 and 9.6 eV. The peak at 9.6 eV is probably related to the same resonance manifold as that leading to SSB, but the other at 6.1 eV may be more restricted to decay into the electronic state 1{sup 3}A{sup ′} (π → π{sup *}) of cytosine via autoionization. The yield function of crosslinks is dominated by a broad peak extending over the 3.6-11.6 eV range with a sharper one at 17.6 eV. The different line shape of the latter function, compared to that of SSB and DSB, appears to be due to the formation of reactive radical sites in the initial supercoiled

  12. Design of reduced size long counter with flat response function from few keV to 20 MeV

    Directory of Open Access Journals (Sweden)

    Mazunga Mohamed

    2016-01-01

    Full Text Available In this study, a reduced size neutron long counter with improved response function was designed using SuperMC simulation code. The main parts of the reduced size long counter are 3He proportional counter, cylindrical moderators made of polyethylene, chromium metal converter, neutron absorber material and outer aluminum cover. A 1.5 cm thick layer of chromium metal was embedded into the hydrogen-rich moderator to enhance response of the long counter at high neutron energies. The radius and length of the long counter was reduced to 15 cm and 35 cm, respectively. In this design we managed to obtain a flat response function from a few keV to 20 MeV energy range. The angular response function, determined at 0.5 MeV and 14 MeV neutron energies, confirmed that the reduced size long counter designed in this study is not significantly affected by in-scattered neutrons. The reduced size long counter is suitable for use as a standard transfer instrument for monitoring neutron fluence in mono-energetic neutron fields.

  13. Study of Radiation Shielding Properties of selected Tropical Wood Species for X-rays in the 50-150 keV Range

    Directory of Open Access Journals (Sweden)

    S. Aggrey-Smith

    2016-03-01

    Full Text Available This paper compares the attenuation coefficients of 20 tropical hard wood species based on their linear and mass attenuation and half value layer (HVL properties for X-rays of energy 50–150 keV using a narrow collimated beam from a Cs-137 source. The narrow collimated beam method made corrections from multiple and small-angle scatterings of photons unnecessary. The attenuation depended on the chemical composition and densities of the wood species. The linear attenuation coefficients of wood species at 50–150 keV were highest for Pterygota macrocarpa (4.53 m−1 and lowest for Antiaris africana (1.24 m−1; the mass attenuation coefficient was highest for Triplochiton scleroxylon (17.62 m2/kg and lowest for Nesogordonia papaverifera (2.27 m2/kg.The HVL was highest for Antiaris africana (0.27 m and lowest for Pterygota macrocarpa (0.149 m. Pterygota macrocarpa of about 0.36 m thickness could serve as a more affordable radiation shielding material against secondary scatter and leakage radiations in place of lead, copper or concrete for low X-ray radiations up to 150 keV.

  14. Measurement of attenuation cross-sections of some fatty acids in the energy range 122–1330 keV

    Indian Academy of Sciences (India)

    GAIKWAD D K; PAWAR P P

    2016-07-01

    The mass attenuation coefficients $(\\mu m)$ have been measured for undecylic acid (C$_{11}$H$_{22}$O$_2$), lauric acid (C$_{12}$H$_{24}$O$_2$), tridecylic acid (C$_{13}$H$_{26}$O$_2$), myristic acid (C$_{14}$H$_{28}$O$_2$), pentadecylic acid (C$_{15}$H$_{30}$O$_2$) andpalmitic acid (C$_{16}$H$_{32}$O$_2$) using $^{57}$Co, $^{133}$Ba, $^{137}$Cs, $^{60}$Co and $^{22}$Na emitted γ radiation with energies 122, 356,511, 662, 1170, 1275 and 1330 keV, respectively. The accurate values of the effective atomic number (Zeff), atomic cross-section $(\\sigma t,)$, electronic cross-section $(\\sigma e)$ and the effective electron density (Neff) have great significance in radiation protection and dosimetry. These quantities were obtained by utilizing experimentally measured values of mass attenuation coefficients $(\\mu m)$. A NaI(Tl) scintillation detector with 8.2% (at 662 keV) resolution was used for detecting of attenuated γ -photons. The variation in Zeff and Neff of fatty acids with energy is discussed. The experimental and theoretical results are in good agreement within 2% deviation.

  15. Analysis of 20 KEV Electron Induced X-Ray Production in Skull, Femur/tibia Bones of Rats

    Science.gov (United States)

    Mehta, Rahul; Watson, Alec; Ali, Nawab; Soulsby, Michael; Chowdhury, Parimal

    2010-04-01

    Hind-limb suspension (HLS) of rats is a NASA validated model of simulated weightlessness. This study examines the effects of microgravity on the skeletal system of rats to assess whether or not exposure of rats to HLS for one week will induce alteration of structural features in selected bones. Four groups of rats were used: two unsuspended controls and two suspended groups. Body weight, food, and water intake were monitored daily before and after suspension. X-rays were measured by a liquid nitrogen cooled Si(li) detector on a Scanning Electron Microscope (SEM) that provided the 20 keV electron beam. X-ray data were collected from square cross sections between 100 μm2 and 104 μm2. The bones were measured for elemental levels of calcium, phosphorus, oxygen and carbon from both control and HLS rats. The average body weight of all HLS groups decreased compared to their respective unsuspended controls. Food and water intake was also lower in both suspended groups. A correlation among HLS and control samples in terms of the distribution of the primary elements was found in the bone tissue when analyzed as a function of position along the hind-leg and within the cross sections.

  16. Charge transfer in keV O+(4S,2D,2P)-He collisions

    Science.gov (United States)

    Lindsay, B. G.; Stebbings, R. F.

    2003-02-01

    Absolute differential cross sections (DCSs) are reported for charge-transfer scattering of (1 5)-keV O+(4S) ground-state and O+(2D,2P) metastable-state ions by helium atoms at angles between 0.2° and 6.3° in the laboratory frame. Estimated ground-state and metastable-state total cross sections are derived from these measurements. The present ground-state cross sections agree satisfactorily with previous measurements for energies above 2 keV and the metastable-state cross sections are consistent with the mixed-state data of Kusakabe et al. [J. Phys. Soc. Japan 59, 1987 (1990)]. The large differences between the ground- and metastable-state cross sections predicted by theory are not observed.

  17. Gamma ray interaction studies of organic nonlinear optical materials in the energy range 122 keV-1330 keV

    Science.gov (United States)

    Awasarmol, V. V.; Gaikwad, D. K.; Raut, S. D.; Pawar, P. P.

    The mass attenuation coefficients (μm) for organic nonlinear optical materials measured at 122-1330 keV photon energies were investigated on the basis of mixture rule and compared with obtained values of WinXCOM program. It is observed that there is a good agreement between theoretical and experimental values of the samples. All samples were irradiated with six radioactive sources such as 57Co, 133Ba, 22Na, 137Cs, 54Mn and 60Co using transmission arrangement. Effective atomic and electron numbers or electron densities (Zeff and Neff), molar extinction coefficient (ε), mass energy absorption coefficient (μen/ρ) and effective atomic energy absorption cross section (σa,en) were determined experimentally and theoretically using the obtained μm values for investigated samples and graphs have been plotted. The graph shows that the variation of all samples decreases with increasing photon energy.

  18. Thermodynamic properties of fluid n-D/sub 2/ in the 75 to 300 K and 2- to 20-kbar range

    Energy Technology Data Exchange (ETDEWEB)

    Liebenberg, D.H.; Mills, R.L.; Bronson, J.C.

    1978-03-01

    The hydrogen isotope deuterium is an important material for use in various energy technologies. This report is a summary of new pressure, volume, temperature, and sound velocity measurements of fluid n-D/sub 2/ in the 75 to 300 K and 2- to 20-kbar range. An equation of state (EOS) was fit to these data. The thermodynamic quantities, volume V, sound velocity v/sub s/, thermal expansivity ..cap alpha../sub p/, heat capacity at constant pressure C/sub p/, isothermal compressibility chi/sub T/, and molar entropy S, are given at 25/sup 0/K and 0.5-kbar increments over the range of measurements. Computer-drawn graphs of the isothermal pressure variation of these quantities are shown. Characteristics of the EOS at high temperature and pressure are determined and compared with theoretical and phenomenological equations of state.

  19. Multispectrum processing approach of weak H sub 2 O profiles recorded with absorption paths ranging from 20 to 120 km

    CERN Document Server

    Mandin, J Y; Jacquemart, D; Picqué, N; Guelachvili, G

    2003-01-01

    A new powerful approach to intracavity laser absorption spectroscopy is explored and evaluated. The laser emission is recorded with a high-resolution time-resolved step-scan Fourier transform interferometer. Time-resolved spectra are obtained from an intracavity laser set-up based on a vertical-cavity surface-emitting semiconductor laser located in the open air of the laboratory. A restricted set of H sub 2 sup 1 sup 6 O lines is used for the evaluation of the method. The lines are measured around 9625 cm sup - sup 1 in more than one hundred time-component spectra simultaneously recorded with absorption path lengths varying in arithmetic progression from 20 up to about 120 km. Data processing is performed with a multispectrum fitting program. The procedure is shown to be efficient for the quantitative determination of molecular parameters of ultra weak transitions.

  20. SURVIVAL DEPTH OF ORGANICS IN ICES UNDER LOW-ENERGY ELECTRON RADIATION ({<=}2 keV)

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, Irene Li; Lignell, Antti; Gudipati, Murthy S., E-mail: gudipati@jpl.nasa.gov [Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 183-301, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

    2012-03-01

    Icy surfaces in our solar system are continually modified and sputtered with electrons, ions, and photons from solar wind, cosmic rays, and local magnetospheres in the cases of Jovian and Saturnian satellites. In addition to their prevalence, electrons specifically are expected to be a principal radiolytic agent on these satellites. Among energetic particles (electrons and ions), electrons penetrate by far the deepest into the ice and could cause damage to organic material of possible prebiotic and even biological importance. To determine if organic matter could survive and be detected through remote sensing or in situ explorations on these surfaces, such as water ice-rich Europa, it is important to obtain accurate data quantifying electron-induced chemistry and damage depths of organics at varying incident electron energies. Experiments reported here address the quantification issue at lower electron energies (100 eV-2 keV) through rigorous laboratory data analysis obtained using a novel methodology. A polycyclic aromatic hydrocarbon molecule, pyrene, embedded in amorphous water ice films of controlled thicknesses served as an organic probe. UV-VIS spectroscopic measurements enabled quantitative assessment of organic matter survival depths in water ice. Eight ices of various thicknesses were studied to determine damage depths more accurately. The electron damage depths were found to be linear, approximately 110 nm keV{sup -1}, in the tested range which is noticeably higher than predictions by Monte Carlo simulations by up to 100%. We conclude that computational simulations underestimate electron damage depths in the energy region {<=}2 keV. If this trend holds at higher electron energies as well, present models utilizing radiation-induced organic chemistry in icy solar system bodies need to be revisited. For interstellar ices of a few micron thicknesses, we conclude that low-energy electrons generated through photoionization processes in the interstellar medium

  1. Strength of the $E_{\\text{cm}} = 1113$ keV resonance in $^{20}${Ne}$(p, \\gamma)^{21}${Na}

    CERN Document Server

    Christian, G; Akers, C; Connolly, D; Fallis, J; Ruiz, C

    2013-01-01

    The $^{20}$Ne$(p, \\gamma)^{21}$Na reaction is the starting point of the NeNa cycle, which is an important process for the production of intermediate mass elements. The $E_{\\text{cm}} = 1113$ keV resonance plays an important role in the determination of stellar rates for this reaction since it is used to normalize experimental direct capture yields at lower energies. The commonly accepted strength of this resonance, $\\omega \\gamma = 1.13 \\pm 0.07$ eV, has been misinterpreted as the strength in the center-of-mass frame when it is actually the strength in the laboratory frame. This has motivated a new measurement of the $E_{\\text{cm}} = 1113$ keV resonance strength in $^{20}$Ne$(p, \\gamma)^{21}$Na using the DRAGON recoil mass spectrometer. The DRAGON result, $0.972 \\pm 0.11$ eV, is in good agreement with the accepted value when both are calculated in the same frame of reference.

  2. Transmission of 18 kev negative ions Cl- through nanocapillariesin Al2O3 membrane

    Institute of Scientific and Technical Information of China (English)

    Lü Xue-Yang; Yin Yong-Zhi; Wang Hong-Wei; Ji Ming-Chao; Chen Lin; Chen Xi-Meng; Jia Juan-Juan; Zhou Peng; Zhou Chun-Lin; Qiu Xi-Yu; Shao Jian-Xiong; Cui Ying

    2011-01-01

    We investigate the angular distribution of the transmitted 18kev negative ions Cl- through Al2O3 nanocapillaries of 50 nm in diameter and 10μm in length. Elastic scattering ions and inelastic scattering ions are obtained simultaneonsly. The experimental result is partially consistent with the guiding effect. We can qualitatively explain our experimental result through a dynamic process.

  3. Measurement of mass attenuation coefficients of some boron compounds and the trommel sieve waste in the energy range 15.746-40.930 keV

    Energy Technology Data Exchange (ETDEWEB)

    Icelli, Orhan E-mail: orhan_icelli@hotmail.com; Erzeneoglu, Salih; Boncukcuoglu, Recep

    2003-05-01

    Mass attenuation coefficients of some boron compounds (H{sub 3}BO{sub 3}, Na{sub 2}B{sub 4}O{sub 7} and B{sub 3}Al{sub 2}O{sub 3}) and the trommel sieve waste (TSW) have been measured by using an extremely narrow collimated-beam transmission method in the energy range 15.746-40.930 keV. The characteristic K{alpha} and K{beta} X-rays of Zr, Mo, Ag, In, Sb, Ba and Pr passed through H{sub 3}BO{sub 3}, Na{sub 2}B{sub 4}O{sub 7}, B{sub 3}Al{sub 2}O{sub 3} and TSW were detected with a high-resolution Si(Li) detector. The measured values are compared with the theoretical ones obtained using the WINXCOM.

  4. Sputtering and crystalline structure modification of bismuth thin films deposited onto silicon substrates under the impact of 20-160 keV Ar{sup +} ions

    Energy Technology Data Exchange (ETDEWEB)

    Mammeri, S. [CRNA/Division des Techniques Nucleaires, B.P. 399, 02 Bd. Frantz Fanon, Alger-Gare, Algiers (Algeria); Ouichaoui, S., E-mail: souichaoui@gmail.co [USTHB/Faculte de Physique, B.P. 32, El-Alia, 16111 Bab Ezzouar, Algiers (Algeria); Ammi, H. [CRNA/Division des Techniques Nucleaires, B.P. 399, 02 Bd. Frantz Fanon, Alger-Gare, Algiers (Algeria); Zemih, R. [USTHB/Faculte de Physique, B.P. 32, El-Alia, 16111 Bab Ezzouar, Algiers (Algeria)

    2010-01-15

    The sputtering of bismuth thin films induced by 20-160 keV Ar{sup +} ions has been studied using Rutherford backscattering spectrometry, scanning electron microscopy and X-ray energy dispersive and diffraction spectroscopy. These techniques revealed increasing modifications of the Bi film surfaces with increasing both ion beam energy and fluence up to their complete deterioration under irradiation conditions E = 160 keV and phi = 1.5 x 10{sup 16} cm{sup -2}, leaving isolated islands of preferred (0 1 2) orientation on the Si substrate. The observed surface morphology and crystalline structure evolutions are likely due to a complex interplay of interaction mechanisms involving both elastic nuclear collisions and inelastic electronic ones. The measured Bi sputtering yields versus Ar{sup +} ion fluence for a fixed ion energy exhibit a significant depression at very low phi-values followed by a steady state regime above approx2.0 x 10{sup 14} cm{sup -2}. Measured sputtering yields versus Ar{sup +} ion energy with fixing ion fluence to 1.2 x 10{sup 16} cm{sup -2} in the upper part of the yield saturation regime are also reported. Their comparison to theoretical model and SRIM 2008 Monte Carlo simulation predictions is discussed.

  5. The Mont Blanc mystery solved? A $m^2=-0.28 keV^2$ neutrino

    CERN Document Server

    Ehrlich, Robert

    2016-01-01

    Evidence is presented in support of a hypothesis made in 2013 predicting the existence of a tachyonic neutrino mass eigenstate doublet having $m^2\\approx -0.2 keV^2$ with $\\Delta m^2=1 eV^2.$ The evidence is based primarily on the puzzling LSD (Mont Blanc) neutrino burst observed on February 23, 1987, which the hypothesis thoroughly explains, with additional support from the Kamiokande-II events recorded on the same day. The probability of the null hypothesis, i.e., that background fluctuations can explain the noted features of the two data sets is estimated to be $4.2\\sigma$ (Mont Blanc), and $3.7\\sigma$ (K-II). Such a controversial hypothesis as a tachyonic neutrino requires absolutely definitive proof, and there may exist a test based on observing the neutrino spectrum from diffuse supernovae that could supply it.

  6. The BeppoSAX 2-10 keV Survey

    CERN Document Server

    Giommi, P; Fiore, F

    2000-01-01

    We present the results of a 2-10 keV BeppoSAX survey based on 140 high galactic latitude MECS fields, 12 of which are deep exposures of ``blank'' parts of the sky. The limiting sensitivity is 5 10^-14 erg cm^-2 s^-1 where about 25% of the Cosmic X-ray Background (CXB) is resolved into discrete sources. The logN-logS function, built with a statistically complete sample of 177 sources, is steep and in good agreement with the counts derived from ASCA surveys. A CXB fluctuation analysis allowed us to probe the logN-logS down to about 1.5 10^-14 erg cm^-2 s^-1 where the contribution of discrete sources to the CXB grows to 40-50%. A hardness ratio analysis reveals the presence of a wide range of spectral shapes and that a fairly large fraction of sources appear to be heavily absorbed, some of which showing soft components. A comparison of the flux distribution of different subsamples confirms the existence of a spectral hardening with decreasing flux. This effect is probably due to an increasing percentage of absor...

  7. Demonstration of Airborne Wide Area Assessment Technologies at Pueblo Precision Bombing Ranges, Colorado. Hyperspectral Imaging, Version 2.0

    Science.gov (United States)

    2007-09-27

    Detection and Ranging (LiDAR) sensors for measuring variation in surface elevation, large-scale orthorectified photography for visual identification of...flown, herbaceous vegetation was dry / senescent due to the late season, and optimal conditions probably existed for discriminating various vegetation...This mapping strategy uses a broader spectrum rather than the VIS/NIR spectrum used in many satellite and photography studies. The SWIR is a key

  8. Proposed experiments to detect keV range sterile neutrinos using energy-momentum reconstruction of beta decay or K-capture events

    CERN Document Server

    Smith, Peter F

    2016-01-01

    Sterile neutrinos in the keV mass range may constitute the galactic dark matter. Various proposed direct detection and laboratory searches are reviewed. The most promising method in the near future is complete energy-momentum reconstruction of individual beta-decay or K-capture events, using atoms suspended in a magneto-optical trap. A survey of suitable isotopes is presented, together with the measurement precision required in a typical experimental configuration. It is concluded that among the most promising are the K-capture isotopes 131Cs, which requires measurement of an X-ray and several Auger electrons in addition to the atomic recoil, and 7Be which has only a single decay product but needs development work to achieve a trapped source. A number of background effects are discussed. It is concluded that sterile neutrinos with masses down to the 5-10 keV region would be detectable, together with relative couplings down to the level 10-10-10-11 in a 1-2 year running time.

  9. Inelastic processes in Na$^{+}-$Ne, Ar and Ne$^{+},$ Ar$^{+}-$Na collisions in energy range $0.5-14$ keV

    CERN Document Server

    Lomsadze, R A; Kezerashvili, R Ya

    2015-01-01

    Absolute cross sections for charge-exchange, ionization and excitation in Na$% ^{+}-$Ne and Na$^{+}-$Ar collisions were measured in the ion energy range $% 0.5-10$ keV using a refined version of a capacitor method, and collision and optical spectroscopy methods simultaneously in the same experimental set-up. Ionization cross sections for Ne$^{+}-$Na and Ar$^{+}-$Na collisions are measured at the energies of $2-14$ keV using a crossed-beam spectroscopy method. The experimental data and the schematic correlation diagrams are used to analyze and determine the mechanisms for these processes. For the charge-exchange process in Na$^{+}$ $-$Ar collisions two nonadiabatic regions are revealed and mechanisms responsible for these regions are explained. Structural peculiarity on the excitation function for the resonance lines of argon atoms in Na$^{+}$ $-$Ar collisions are observed and the possible mechanisms of this phenomenon are explored. The measured ionization cross sections for Na$^{+}-$Ne and Ne$^{+}-$Na collisi...

  10. Inelastic processes in Na+-Ne, Na+-Ar, Ne+-Na, and Ar+-Na collisions in the energy range 0.5-14 keV

    Science.gov (United States)

    Lomsadze, R. A.; Gochitashvili, M. R.; Kezerashvili, R. Ya.

    2015-12-01

    Absolute cross sections for charge-exchange, ionization, and excitation in Na+-Ne and Na+-Ar collisions were measured in the ion energy range 0.5 -10 keV using a refined version of a capacitor method and collision and optical spectroscopy methods simultaneously in the same experimental setup. Ionization cross sections for Ne+-Na and Ar+-Na collisions are measured at energies of 2 -14 keV using a crossed-beam spectroscopy method. The experimental data and the schematic correlation diagrams are used to analyze and determine the mechanisms for these processes. For the charge-exchange process in Na+-Ar collisions two nonadiabatic regions are revealed and mechanisms responsible for these regions are explained. Structural peculiarity on the excitation function for the resonance lines of argon atoms in Na+-Ar collisions are observed and the possible mechanisms of this phenomenon are explored. The measured ionization cross sections for Na+-Ne and Ne+-Na collisions in conjunction with the Landau-Zener formula are used to determine the coupling matrix element and transition probability in a region of pseudocrossing of the potential curves.

  11. Photon interaction study of organic nonlinear optical materials in the energy range 122-1330 keV

    Science.gov (United States)

    Awasarmol, Vishal V.; Gaikwad, Dhammajyot K.; Raut, Siddheshwar D.; Pawar, Pravina P.

    2017-01-01

    In the present study, the mass attenuation coefficient (μm) of six organic nonlinear optical materials has been calculated in the energy range 122-1330 keV and compared with the obtained values from the WinXCOM program. It is found that there is a good agreement between theoretical and experimental values (<3%). The linear attenuation coefficients (μ) total atomic cross section (σt, a), and total electronic cross section (σt, el) have also been calculated from the obtained μm values and their variations with photon energy have been plotted. From the present work, it is observed that the variation of obtained values of μm, μ, σt, a, and σt, el strongly depends on the photon energy and decreases or increases due to chemical composition and density of the sample. All the samples have been studied extensively using transmission method with a view to utilize the material for radiation dosimetry. Investigated samples are good material for radiation dosimetry due their low effective atomic number. The mass attenuation coefficient (μm), linear attenuation coefficients (μ), total atomic cross section (σt, a), total electronic cross section (σt, el), effective atomic numbers (Zeff), molar extinction coefficient (ε), mass energy absorption coefficient (μen/ρ) and effective atomic energy absorption cross section (σa, en) of all sample materials have been carried out and transmission curves have been plotted. The transmission curve shows that the variation of all sample materials decreases with increasing photon energy.

  12. Elastic and inelastic processes in He/sup +/-H/sub 2/ collisions between 2 and 30 keV

    Energy Technology Data Exchange (ETDEWEB)

    Bergnes, C.; Bordenave-Montesquieu, D.; Boutonnet, A.; Nouet, P.; Dagnac, R.

    1986-10-14

    The elastic and inelastic processes have been studied for scattering of He/sup +/ ions by H/sub 2/ molecules between 2 and 30 keV in the angular range from 10' to 3/sup 0/ by an energy loss technique. The analysis of elastic energy loss against E/sub 0/theta/sup 2/ shows that the incident ion is scattered by the entire molecule at low energies whereas at high energies it is scattered by only one atom in the target. Comparison of the relative probabilities of the various excitation processes with the isoelectronic system He/sup +/-He demonstrates the different behaviours of a molecular target in the excitation mechanism.

  13. Calorimetry for dose measurement at electron accelerators in the 80-120 keV energy range

    DEFF Research Database (Denmark)

    Helt-Hansen, J.; Miller, A.; Duane, S.

    2005-01-01

    Calorimeters for dose measurement at low-energy electron accelerator energies (80-120 keV) are described. Three calorimeters with different characteristics were designed and their dose response and measurement uncertainties were characterized. The heated air between the beam exit window and the c...

  14. Dynamical simulations of radiation damage induced by 10 keV energetic recoils in UO 2

    Science.gov (United States)

    Tian, X. F.; Gao, T.; Long, Chongsheng; Li, JiuKai; Jiang, Gang; Xiao, Hongxing

    2011-08-01

    We have performed classical molecular dynamics simulations to simulate the primary damage state induced by 10 keV energetic recoils in UO 2. The numbers versus time and the distance distributions for the displaced uranium and oxygen atoms were investigated with the energetic recoils accelerated along four different directions. The simulations suggest that the direction of the primary knock-on atom (PKA) has no effect on the final primary damage state. In addition, it was found that atomic displacement events consisted of replacement collision sequences in addition to the production of Frenkel pairs. The spatial distribution of defects introduced by 10 keV collision cascades was also presented and the results were similar to that of energetic recoils with lower energy.

  15. A DATABASE OF >20 keV ELECTRON GREEN'S FUNCTIONS OF INTERPLANETARY TRANSPORT AT 1 AU

    Energy Technology Data Exchange (ETDEWEB)

    Agueda, N.; Sanahuja, B. [Departament d' Astronomia i Meteorologia, Institut de Ciencies del Cosmos, Universitat de Barcelona, Barcelona (Spain); Vainio, R. [Department of Physics, University of Helsinki, Helsinki (Finland)

    2012-10-15

    We use interplanetary transport simulations to compute a database of electron Green's functions, i.e., differential intensities resulting at the spacecraft position from an impulsive injection of energetic (>20 keV) electrons close to the Sun, for a large number of values of two standard interplanetary transport parameters: the scattering mean free path and the solar wind speed. The nominal energy channels of the ACE, STEREO, and Wind spacecraft have been used in the interplanetary transport simulations to conceive a unique tool for the study of near-relativistic electron events observed at 1 AU. In this paper, we quantify the characteristic times of the Green's functions (onset and peak time, rise and decay phase duration) as a function of the interplanetary transport conditions. We use the database to calculate the FWHM of the pitch-angle distributions at different times of the event and under different scattering conditions. This allows us to provide a first quantitative result that can be compared with observations, and to assess the validity of the frequently used term beam-like pitch-angle distribution.

  16. The 2-10 keV X-Ray Background Dipole and Its Cosmological Implications

    Science.gov (United States)

    Scharf, C. A.; Jahoda, K.; Treyer, M.; Lahav, O.; Boldt, E.; Piran, T.

    2000-11-01

    The hard X-ray (>2 keV) emission of the local and distant universe as observed with the HEAO 1 A-2 experiment is reconsidered in the context of large-scale cosmic structure. Using all-sky X-ray samples of active galactic nuclei (AGNs) and galaxy clusters, we remove the dominant local X-ray flux from within a redshift of ~0.02. We evaluate the dipolar and higher order harmonic structure in four X-ray colors. The estimated dipole anisotropy of the unresolved flux appears to be consistent with a combination of the Compton-Getting effect due to the Local Group motion (dipole amplitude Δ=0.0042) and remaining large-scale structure (0.00232 keV Galactic X-ray emission. Comparison of the soft and hard color maps with a harmonic analysis of the 1.5 keV ROSAT all-sky data qualitatively suggests that at least a third of the faint, unresolved ~18° scale structure in the HEAO 1 A-2 data may be Galactic in origin. However, the effect on measured flux dipoles is small (frame can constrain the amplitude of bulk motions of the universe. From observed bulk motions over a local ~50 h-1 Mpc radius volume, we determine 0.14<~Ω0.60/bX(0)<~0.59, where Ω0 is the universal density parameter and bX(0) is the present-epoch bias parameter, defined as the ratio of fluctuations in the X-ray source density and the mass density.

  17. Echo 2 - Observations at Fort Churchill of a 4-keV peak in low-level electron precipitation

    Science.gov (United States)

    Arnoldy, R. L.; Hendrickson, R. A.; Winckler, J. R.

    1975-01-01

    The Echo 2 rocket flight launched from Fort Churchill, Manitoba, offered the opportunity to observe high-latitude low-level electron precipitation during quiet magnetic conditions. Although no visual aurora was evident at the time of the flight, an auroral spectrum sharply peaked at a few keV was observed to have intensities from 1 to 2 orders of magnitude lower than peaked spectra typically associated with bright auroral forms. There is a growing body of evidence that relates peaked electron spectra to discrete aurora. The Echo 2 observations show that whatever the mechanism for peaking the electron spectrum in and above discrete forms, it operates over a range of precipitation intensities covering nearly 3 orders of magnitude down to subvisual or near subvisual events.

  18. Atomic, Molecular, and Optical Physics: Optical Excitation Function of H(1s-2p) Produced by electron Impact from Threshold to 1.8 keV

    Science.gov (United States)

    James, G. K.; Slevin, J. A.; Shemansky, D. E.; McConkey, J. W.; Bray, I.; Dziczek, D.; Kanik, I.; Ajello, J. M.

    1997-01-01

    The optical excitation function of prompt Lyman-Alpha radiation, produced by electron impact on atomic hydrogen, has been measured over the extended energy range from threshold to 1.8 keV. Measurements were obtained in a crossed-beams experiment using both magnetically confined and electrostatically focused electrons in collision with atomic hydrogen produced by an intense discharge source. A vacuum-ultraviolet mono- chromator system was used to measure the emitted Lyman-Alpha radiation. The absolute H(1s-2p) electron impact excitation cross section was obtained from the experimental optical excitation function by normalizing to the accepted optical oscillator strength, with corrections for polarization and cascade. Statistical and known systematic uncertainties in our data range from +/- 4% near threshold to +/- 2% at 1.8 keV. Multistate coupling affecting the shape of the excitation function up to 1 keV impact energy is apparent in both the present experimental data and present theoretical results obtained with convergent close- coupling (CCC) theory. This shape function effect leads to an uncertainty in absolute cross sections at the 10% level in the analysis of the experimental data. The derived optimized absolute cross sections are within 7% of the CCC calculations over the 14 eV-1.8 keV range. The present CCC calculations converge on the Bethe- Fano profile for H(1s-2p) excitation at high energy. For this reason agreement with the CCC values to within 3% is achieved in a nonoptimal normalization of the experimental data to the Bethe-Fano profile. The fundamental H(1s-2p) electron impact cross section is thereby determined to an unprecedented accuracy over the 14 eV - 1.8 keV energy range.

  19. Exploring pseudo-Nambu-Goldstone bosons by stimulated photon colliders in the mass range 0.1 eV to 10 keV

    Science.gov (United States)

    Homma, Kensuke; Toyota, Yuichi

    2017-06-01

    Searching for pseudo-Nambu-Goldstone bosons (pNGBs) in weak-coupling domains is crucial for understanding the dark components in the universe. We propose searching for pNGBs coupled to 2 photons in the mass range from 0.1 eV to 10 keV. This could provide opportunities to test string-theory-based pNGBs beyond the GUT scale M ˜ 10^{16} GeV included in the weak coupling proportional to M^{-1}. We provide formulae that are applicable to photon-photon scattering via a pNGB resonance exchange with a stimulation process in an asymmetric head-on photon-photon collider by mixing 3 laser pulses in laboratory experiments. We discuss the quantum electrodynamic effects on the pNGB exchange in the same mass-coupling domain as a background process from the standard model. We find that a large unexplored mass-coupling domain is accessible by combining existing laser facilities, including free-electron lasers.

  20. Electronic sputtering of solid O{sub 2} by keV Ne ions

    Energy Technology Data Exchange (ETDEWEB)

    Pedrys, Roman [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, ul. Reymonta 4, 30-059 Krakow (Poland); Anders, Christian [Fachbereich Physik und Forschungszentrum OPTIMAS, Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern (Germany); Urbassek, Herbert M., E-mail: urbassek@rhrk.uni-kl.de [Fachbereich Physik und Forschungszentrum OPTIMAS, Universität Kaiserslautern, Erwin-Schrödinger-Straße, D-67663 Kaiserslautern (Germany)

    2015-07-01

    Sputtering of a solid oxygen target is studied both by experiment and by computer simulation. Experimental data of the translational energy distributions of sputtered O{sub 2} molecules are measured for 250 and 750 eV Ne impact; this process is also studied using molecular dynamics computer simulation. Translational energy distributions coincide well for high ejection energies; this proves that the collisional part of the sputtering process is well described by computer simulation. Deviations exist at the low-energy side, below around 0.3 eV; these are assigned to electronic excitations and exothermic chemical reactions that have not been included in the computer model. We show that the sputter contribution from electronic excitation is very similar to that found for 2–9 keV H{sub 2} and H{sub 3} impact and for electron impact at sub-keV energies. Our results thus allow us to separate collisional from electronic sputtering.

  1. The Morphology of the X-ray Emission above 2 keV from Jupiter's Aurorae

    Science.gov (United States)

    Elsner, R.; Branduardi-Raymont, G.; Galand, M.; Grodent, D.; Gladstone, G. R.; Waite, J. H.; Cravens, T.; Ford, P.

    2007-01-01

    The discovery in XMM-Newton X-ray data of X-ray emission above 2 keY from Jupiter's aurorae has led us to reexamine the Chandra ACIS-S observations taken in Feb 2003. Chandra's superior spatial resolution has revealed that the auroral X-rays with E > 2 keV are emitted from the periphery of the region emitting those with E morphology to that of the FUV emission from the main auroral oval and the polar cap. The low energy emission has previously been established as due to charge exchange between energetic precipitating ions of oxygen and either sulfur or carbon. It seems likely to us that the higher energy emission is due to precipitation of energetic electrons, possibly the same population of electrons responsible for the FUV emission. We discuss our analysis and interpretation.

  2. Energy response of GR-200A thermoluminescence dosemeters to 60Co and to monoenergetic synchrotron radiation in the energy range 28-40 keV.

    Science.gov (United States)

    Emiro, F; Di Lillo, F; Mettivier, G; Fedon, C; Longo, R; Tromba, G; Russo, P

    2016-01-01

    The response of LiF:Mg,Cu,P thermoluminescence dosemeters (type GR-200A) to monoenergetic radiation of energy 28, 35, 38 and 40 keV was evaluated with respect to irradiation with a calibrated (60)Co gamma-ray source. High-precision measurements of the relative air kerma response performed at the SYRMEP beamline of the ELETTRA synchrotron radiation facility (Trieste, Italy) showed a significant deviation of the average response to low-energy X-rays from that to (60)Co, with an over-response from 6 % (at 28 keV) to 22 % (at 40 keV). These data are not consistent with literature data for these dosemeters, where model predictions gave deviation from unity of the relative air kerma response of about 10 %. The authors conclude for the need of additional determinations of the low-energy relative response of GR-200A dosemeters, covering a wider range of monoenergetic energies sampled at a fine energy step, as planned in future experiments by their group at the ELETTRA facility. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Study of effective atomic number and electron density for tissues from human organs in the energy range of 1 keV-100 GeV.

    Science.gov (United States)

    Manjunatha, H C; Rudraswamy, B

    2013-02-01

    Effective atomic numbers' (Z(eff)) effective electron density (N(el)) for human organs and tissues have been computed in the energy region of 1 keV to 100 GeV using WinXCOM. The computed data of Z(eff) and N(el) are tabulated. The computed values are compared with previous results. The computed data of Z(eff)and N(el)for almost all tissues (34 tissues of different human organs) in the given energy range are not available in literature and find application in radiotherapy and dosimetry.

  4. Comparison of Martian meteorites with earth composition: Study of effective atomic numbers in the energy range 1 keV-100 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Ün, Adem, E-mail: ademun25@yahoo.com; Han, İbrahim, E-mail: ibrahimhan25@hotmail.com [Ağrı İbrahim Çeçen University, Faculty of Arts and Sciences, Department of Physics, 04100 Ağrı (Turkey); Ün, Mümine, E-mail: mun@agri.edu.tr [Ağrı İbrahim Çeçen University, Vocational School, Department of Electricity and Energy, 04100 Ağrz (Turkey)

    2016-04-18

    Effective atomic (Z{sub eff}) and electron numbers (N{sub eff}) for 24 Martian meteorites have been determined in the energy range from 1 keV to 100 GeV and also for sixteen significant energies of commonly used radioactive sources. The values of Z{sub eff} and N{sub eff} for all sample were obtained from the DirectZeff program. The obtained results for Martian meteorites have been compared with the results for Earth composition and similarities or differences also evaluated.

  5. Web 2.0

    CERN Document Server

    Han, Sam

    2012-01-01

    Web 2.0 is a highly accessible introductory text examining all the crucial discussions and issues which surround the changing nature of the World Wide Web. It not only contextualises the Web 2.0 within the history of the Web, but also goes on to explore its position within the broader dispositif of emerging media technologies.The book uncovers the connections between diverse media technologies including mobile smart phones, hand-held multimedia players, ""netbooks"" and electronic book readers such as the Amazon Kindle, all of which are made possible only by the Web 2.0. In addition, Web 2.0 m

  6. Study of {sup nat}Mg(d,d{sub 0}) reaction at detector angles between 90° and 170°, for the energy range E{sub d,lab}=1660–1990 keV

    Energy Technology Data Exchange (ETDEWEB)

    Patronis, N., E-mail: npatronis@uoi.gr [Department of Physics, University of Ioannina, 45110 Ioannina (Greece); Aslanoglou, X. [Department of Physics, University of Ioannina, 45110 Ioannina (Greece); Axiotis, M. [Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, N.C.S.R. Demokritos, Aghia Paraskevi, 15310 Athens (Greece); Georgiadou, A. [Department of Physics, University of Ioannina, 45110 Ioannina (Greece); Kokkoris, M. [Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens (Greece); Lagoyannis, A. [Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, N.C.S.R. Demokritos, Aghia Paraskevi, 15310 Athens (Greece); Misaelides, P. [Department of Chemistry, Aristotle University, GR-54124 Thessaloniki (Greece); Paneta, V. [Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, N.C.S.R. Demokritos, Aghia Paraskevi, 15310 Athens (Greece); Department of Physics, National Technical University of Athens, Zografou Campus, 15780 Athens (Greece)

    2014-10-15

    In the present work, the study of the {sup nat}Mg(d,d{sub 0}) is presented for the energy range E{sub d,lab} = 1660–1990 keV (in steps of 5 keV), for detector angles between 90° and 170°. Elastic scattering data for two forward angles (55° and 70°) were also obtained. In order to validate the obtained experimental results a thick Mg sample with Au evaporated on top was fabricated and benchmarking measurements were performed at various deuteron beam energies. The results of the present work are complementary to the recently published {sup 24}Mg(d,p{sub 0,1,2}) reaction cross section data, thus facilitating the simultaneous depth profiling study of magnesium by both the d-NRA and EBS techniques.

  7. Simple parametrization of photon mass energy absorption coefficients of H-, C-, N- and O-based samples of biological interest in the energy range 200–1500 keV

    Indian Academy of Sciences (India)

    V Manjunathaguru; T K Umesh

    2009-02-01

    In this paper, we provide polynomial coefficients and a semi-empirical relation using which one can derive photon mass energy absorption coefficient of any H-, C-, N-, O-based sample of biological interest containing any other elements in the atomic number range 2–40 and energy range 200–1500 keV. More interestingly, it has been observed in the present work that in this energy range, both the mass attenuation coefficients and the mass energy absorption coefficients for such samples vary only with respect to energy. Hence it was possible to represent the photon interaction properties of such samples by a mean value of these coefficients. By an independent study of the variation of the mean mass attenuation coefficient as well as mass energy absorption coefficient with energy, two simple semi-empirical relations for the photon mass energy absorption coefficients and one relation for the mass attenuation coefficient have been obtained in the energy range 200–1500 keV. It is felt that these semi-empirical relations can be very handy and convenient in biomedical and other applications. One possible significant conclusion based on the results of the present work is that in the energy region 200–1500 keV, the photon interaction characteristics of any H-, C-, N-, O-based sample of biological interest which may or may not contain any other elements in the atomic number range 2–40 can be represented by a sample-independent (single) but energy-dependent mass attenuation coefficient and mass energy absorption coefficient.

  8. A satellite-borne ion mass spectrometer for the energy range 0 to 16 keV

    Science.gov (United States)

    Balsiger, H.; Eberhardt, P.; Geiss, J.; Ghielmetti, A.; Walker, H. P.; Young, D. T.; Loidl, H.; Rosenbauer, H.

    1976-01-01

    The Ion Composition Experiment (ICE) on GEOS represents the first comprehensive attempt to measure the positive ion composition at high altitudes in the magnetosphere. Due to the heterogeneous nature of the magnetospheric plasma a novel mass spectrometer has been developed to cover the mass per charge range from H-1(+) to beyond Ba-138(+) and the energy per charge range from 0 to 16 keV/e. The ICE consists primarily of a cylindrical electrostatic analyzer followed by a curved analyzer incorporating crossed magnetic and electric fields. This combination has limited angular and energy focusing properties, but it maintains a mass resolution of about 4 over a wide range in energy and mass, sufficient for the objectives of measuring plasmas of both solar and terrestrial origin. High sensitivity and low background should allow measurements of rarer ion constituents down to flux levels of 0.01 ions/sq cm sec ster eV. A sophisticated electronics combined with powerful ground computer and telecommand systems allow for very efficient scanning of the mass-energy space.

  9. Effect of spectral shape in the relative efficiency of LiF: Mg,Ti exposed to 20 keV effective energy X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Ixquiac-Cabrera, J.M., E-mail: mixquiac@nucleares.unam.m [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, A.P. 70-543, 04510 DF (Mexico); Departamento de Fisica, Universidad de San Carlos de Guatemala, Edificio T-1 Facultad de Ingenieria (Guatemala); Brandan, M.E.; Martinez-Davalos, A.; Rodriguez-Villafuerte, M.; Ruiz-Trejo, C. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, A.P. 20-364, 01000 DF (Mexico); Gamboa-deBuen, I. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, A.P. 70-543, 04510 DF (Mexico)

    2011-04-15

    This work is aimed at studying the possible dependence of the thermoluminescent response of LiF:Mg,Ti (TLD-100) on the X-ray beam spectrum. TLD-100 chips were irradiated with 20 keV effective energy filtered tungsten X-ray spectra, generated by a tube operated at 30, 40, 50, 60, 70 and 80 kV, and the response was measured relative to the response to {sup 60}Co gammas. TLDs were exposed in air at air kerma values between 50 and 300 mGy. Glow curve deconvolution into 8 peaks (3, 4, 5, 6a, 6b, 7, 8 and 9) was performed in order to evaluate the response of individual peaks and regions of interest in the glow curve. Results show that all peaks display a linear response, at least up to 200 mGy, for all X-ray beam qualities. The relative response of the total glow curve area, the dosimetric region (peaks 3 + 4 + 5) and peaks 5 to 9 is statistically constant for beams generated by voltages from 30 to 70 kV; for 80 kV, the values are lower by about 20% for peaks 8 and 9 and 9% for the rest. The relative efficiency for the glow curve area, the dosimetric region and peaks 5 (1.15, 1.10 and 1.13), peaks 8 and 9 (2.05 and 1.55) do not depend on the beam spectrum between 30 and 70 kV, while for 80 kV the efficiency is lower. For peaks 6a, 6b and 7, relative efficiencies (1.91, 2.94 and 2.60) are voltage independent.

  10. ART: Surveying the Local Universe at 2-11 keV

    Science.gov (United States)

    O'Dell, S. L.; Ramsey, B. D.; Adams, M. L.; Brandt, W. N.; Bubarev, M. V.; Hassinger, G.; Pravlinski, M.; Predehl, P.; Romaine, S. E.; Swartz, D. A.; Urry, C. M.; Vikhlinin, A.; Weisskopf, M. C.

    2008-01-01

    The Astronomical Rontgen Telescope (ART) is a medium-energy x-ray telescope system proposed for the Russian-led mission Spectrum Rontgen-Gamma (SRG). Optimized for performance over the 2-11-keV band, ART complements the softer response of the SRG prime instrument-the German eROSITA x-ray telescope system. The anticipated number of ART detections is 50,000-with 1,000 heavily-obscured (N(sub H)> 3x10(exp 23)/sq cm) AGN-in the SRG 4-year all-sky survey, plus a comparable number in deeper wide-field (500 deg(sup 2) total) surveys. ART's surveys will provide a minimally-biased, nearly-complete census of the local Universe in the medium-energy x-ray band (including Fe-K lines), at CCD spectral resolution. During long (approx.100-ks) pointed observations, ART can obtain statistically significant spectral data up to about 15 keY for bright sources and medium-energy x-ray continuum and Fe-K-line spectra of AGN detected with the contemporaneous NuSTAR hard-x-ray mission.

  11. The 2-10 keV luminosity as a Star Formation Rate indicator

    CERN Document Server

    Ranalli, P; Setti, G

    2003-01-01

    Radio and far infrared luminosities of star-forming galaxies follow a tight linear relation. Making use of ASCA and BeppoSAX observations of a well-defined sample of nearby star-forming galaxies, we argue that tight linear relations hold between the X-ray, radio and far infrared luminosities. The effect of intrinsic absorption is investigated taking NGC3256 as a test case. It is suggested that the hard X-ray emission is directly related to the Star Formation Rate. Star formation processes may also account for most of the 2-10 keV emission from LLAGNs of lower X-ray luminosities (for the same FIR and radio luminosity). Deep Chandra observations of a sample of radio-selected star-forming galaxies in the Hubble Deep Field North show that the same relation holds also at high (0.2< z< 1.3) redshift. The X-ray/radio relations also allow a derivation of X-ray number counts up to very faint fluxes from the radio Log N-Log S, which is consistent with current limits and models. Thus the contribution of star-formi...

  12. Non-dissociative and dissociative ionisation of H sub 2 by 50-2000 keV antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, L.H.; Hvelplund, P.; Knudsen, H.; Moeller, S.P.; Pedersen, J.O.P.; Tang-Petersen, S.; Uggerhoej, E. (Aarhus Univ. (Denmark). Inst. of Physics); Elsener, K. (European Organization for Nuclear Research, Geneva (Switzerland)); Morenzoni, E. (Paul Scherrer Inst. (PSI), Villigen (Switzerland))

    1990-08-14

    A beam of antiprotons with energies between 50 keV and 2 MeV has been used for measurements of non-dissociative ionisation and dissociative ionisation cross sections of H{sub 2}. The results are compared with cross sections for equivelocity protons and electrons, and the role of interference effects in two-electron processes is discussed. (author).

  13. ARLearn 2.0

    NARCIS (Netherlands)

    Ternier, Stefaan; Tabuenca, Bernardo; Klemke, Roland; Specht, Marcus

    2013-01-01

    Ternier, S., Tabuenca, B., Klemke, R., & Specht, M. (2012). ARLearn (version 2.0) [Software]. Heerlen, The Netherlands: Open Universiteit. Available under the GNU Lesser General Public License (LGPL3)

  14. ARLearn 2.0

    NARCIS (Netherlands)

    Ternier, Stefaan; Tabuenca, Bernardo; Klemke, Roland; Specht, Marcus

    2013-01-01

    Ternier, S., Tabuenca, B., Klemke, R., & Specht, M. (2012). ARLearn (version 2.0) [Software]. Heerlen, The Netherlands: Open Universiteit. Available under the GNU Lesser General Public License (LGPL3)

  15. A 7.2 keV spherical crystal backlighter system for Sandia's Z Pulsed Power Facility

    Science.gov (United States)

    Schollmeier, M.; Knapp, P. F.; Ampleford, D. J.; Loisel, G. P.; Robertson, G.; Shores, J. E.; Smith, I. C.; Speas, C. S.; Porter, J. L.; McBride, R. D.

    2016-10-01

    Many experiments on Sandia's Z facility, a 30 MA, 100 ns rise-time, pulsed-power driver, use a monochromatic Quartz crystal imaging backlighter system at 1.865 keV (Si Heα) or 6.151 keV (Mn Heα) x-ray energy to radiograph an imploding liner (cylindrical tube) or wire array. The x-ray source is generated by the Z-Beamlet Laser (ZBL), which provides up to 4.5 kJ at 527 nm during a 6 ns window. Radiographs of an imploding thick-walled Beryllium liner at a convergence ratio of about 20 [CR =Rin . (0) /Rin . (t) ] were too opaque to identify the inner surface of the liner with high confidence, demonstrating the need for a higher-energy x-ray backlighter between 6 and 10 keV. We present the design, test and first application of a Ge (335) spherical crystal x-ray backlighter system using the 7.242 keV Co Heα resonance line. The system operates at an almost identical Bragg angle as the existing 1.865 and 6.151 keV backlighters, enhancing our capabilities such as two-color, two-frame radiography, without changing detector shielding hardware. SAND No: SAND2016-6724 A. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corp., a wholly owned subsidiary of Lockheed Martin Corp., for the U.S. DoE NNSA under contract DE-AC04-94AL85000.

  16. Kemi 2.0

    DEFF Research Database (Denmark)

    Johannesson, Anne Boie

    2014-01-01

    temaer, hvor eleverne laver deres eget didaktiske design indenfor rammerne af lærerens didaktiske design. Fokus i gruppearbejdet er udarbejdelse af web 2.0-produkter og meningsforhandling. Lærerens rolle er at hjælpe når der er behov for det, fremfor at lave almindelig tavleundervisning. Kemi 2.0 ligger......I dette projekt undersøges det hvordan kemi C på stx kan gøres it-baseret og almendannende. Løsningen er elevaktiverende og temabaseret undervisning samt fokus på kompetencer, fremfor kun på kvalifikationer. Det didaktiske design af kemi 2.0 er baseret på socialkonstruktivismen og inspireret af...... Dewey, Kolb, Illeris, Wenger og Luhmann. De unge karakteriseres med udgangspunkt i forskellige generationsbeskrivelser, og principper for didaktik 2.0, der imødekommer de unges forventninger og måder at lære på, skitseres. Principperne i kemi 2.0 er længerevarende gruppearbejde indenfor vedkommende...

  17. Comparison of simulated and measured spectra from an X-ray tube for the energies between 20 and 35 keV

    Science.gov (United States)

    Yücel, M.; Emirhan, E.; Bayrak, A.; Ozben, C. S.; Yücel, E. Barlas

    2015-11-01

    Design and production of a simple and low cost X-ray imaging system that can be used for light industrial applications was targeted in the Nuclear Physics Laboratory of Istanbul Technical University. In this study, production, transmission and detection of X-rays were simulated for the proposed imaging device. OX/70-P dental tube was used and X-ray spectra simulated by Geant4 were validated by comparison with X-ray spectra measured between 20 and 35 keV. Relative detection efficiency of the detector was also determined to confirm the physics processes used in the simulations. Various time optimization tools were performed to reduce the simulation time.

  18. Comparison of simulated and measured spectra from an X-ray tube for the energies between 20 and 35 keV

    Energy Technology Data Exchange (ETDEWEB)

    Yücel, M.; Emirhan, E.; Bayrak, A.; Ozben, C.S.; Yücel, E. Barlas, E-mail: barlase@itu.edu.tr

    2015-11-01

    Design and production of a simple and low cost X-ray imaging system that can be used for light industrial applications was targeted in the Nuclear Physics Laboratory of Istanbul Technical University. In this study, production, transmission and detection of X-rays were simulated for the proposed imaging device. OX/70-P dental tube was used and X-ray spectra simulated by Geant4 were validated by comparison with X-ray spectra measured between 20 and 35 keV. Relative detection efficiency of the detector was also determined to confirm the physics processes used in the simulations. Various time optimization tools were performed to reduce the simulation time.

  19. Eyeborg 2.0

    OpenAIRE

    Lizana García, Matias

    2011-01-01

    Finalista del Premi Cercle Fiber al millor Projecte Final de Carrera (curs 2010-2011) Les persones amb acromatòpsia no poden captar el color. Eyeborg 2.0 permet, a través d'una càmera integrada en un sistema embedded, captar els colors i transformar-los a sons.

  20. Measurement of the e+e-→K+K- cross section in the energy range √{s }=1.05 -2.0 GeV

    Science.gov (United States)

    Achasov, M. N.; Aulchenko, V. M.; Barnyakov, A. Yu.; Barnyakov, M. Yu.; Beloborodov, K. I.; Berdyugin, A. V.; Berkaev, D. E.; Bogdanchikov, A. G.; Botov, A. A.; Buzykaev, A. R.; Dimova, T. V.; Druzhinin, V. P.; Golubev, V. B.; Kardapoltsev, L. V.; Kharlamov, A. G.; Kononov, S. A.; Koop, I. A.; Korol, A. A.; Koshuba, S. V.; Kovrizhin, D. P.; Kravchenko, E. A.; Kupich, A. S.; Lysenko, A. P.; Martin, K. A.; Obrazovsky, A. E.; Onuchin, A. P.; Otboyev, A. V.; Pakhtusova, E. V.; Perevedentsev, E. A.; Rogovsky, Yu. A.; Serednyakov, S. I.; Shatunov, Yu. M.; Shatunov, P. Yu.; Shtol, D. A.; Silagadze, Z. K.; Skrinsky, A. N.; Surin, I. K.; Tikhonov, Yu. A.; Usov, Yu. V.; Vasiljev, A. V.; Zemlyansky, I. M.

    2016-12-01

    The e+e-→K+K- cross section is measured in the center-of-mass energy range 1.05-2.00 GeV at the SND detector. The measurement is based on data with an integrated luminosity of 35 pb-1 collected at the VEPP-2000 e+e--collider. The obtained results are consistent with the previous most accurate data obtained in the BABAR experiment and have a comparable accuracy.

  1. SIMBOL-X: the problem of the calibrating a 0.5-80 keV 20m focal length focussing telescope

    Science.gov (United States)

    Basso, S.; Spiga, D.; Pareschi, G.; Citterio, O.; Malaguti, G.; Burkert, W.; Freyberg, M.

    2007-09-01

    Simbol-X is a hard X-ray telescope being developed by France and Italy, with the participation of Germany, that will operate in the 0.5-80 keV. Simbol-X will allow, in the key 10-40 keV band, a two order of magnitude leap both in sensitivity and angular resolution, by means of a hybrid focal plane coupled with a 20m focal length multi-layer coated X-ray mirrors. The novel telescope architecture and its three-decade extended energy band translate however into technical issues never addressed before for what concerns the on-ground calibrations. In fact, at least in the full-illumination geometry, the unprecedented focal length causes, due to the calibration source finite distance, two main problems: (a) a non-negligible increase of the fraction of incident photons undergoing only one reflection (in the parabola); (b) a variation of the reflectivity curve between parabola and hyperbola, due to a corresponding variation of the incidence angle of incoming photons. In this work, the issue of calibrating a 20m X-ray focussing telescope is addressed in details, and technical solutions are envisaged and proposed to tackle and minimized the above mentioned problems.

  2. Sputtering of Thick Deuterium Films by KeV Electrons

    DEFF Research Database (Denmark)

    Thestrup Nielsen, Birgitte; Svendsen, Winnie Edith; Schou, Jørgen;

    1994-01-01

    Sputtering of thick films of solid deuterium up to several μm by keV electrons is reported for the first time. The sputtering yield increases within a narrow range of thicknesses around 1.6 μm by about 2 orders of magnitude for 1.5 keV electrons. A similar behavior has not been observed for ion...

  3. Measurement of K-X-rays fluorescence cross-sections, fluorescence yields and intensity ratios for elements in the atomic range 21 < Z < 74 excited by 59 keV photons

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Avila, J.; Lopez-Pino, N.; Padilla-Cabal, F.; Van Espen, P.; Cabal, A.; Pena, M. Ruiz; Alessandro, K.D.; Maidana, N.L. [Instituto Superior de Tecnologia y Ciencias Aplicadas (InSTEC), La Habana (Cuba); Antwerp Univ. (Belgium). Micro Trace Analytical Center; CEADEN, La Habana (Cuba); Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica. Lab. do Acelerador Linear

    2010-07-01

    Full text: Using 59 keV photons, we measured the K{sub {alpha}}, K{sub {beta}} and total K X-rays fluorescence cross sections of 17 elements in the atomic range 21 < Z < 74. Furthermore, the fluorescence yields and the I{sub K{beta}} / I{sub K{alpha}} intensity ratios for these elements were also determined. An annular radioactive source of {sup 241}Am (activity 1 Ci) was employed to excite the elements in targets with the shape of foils or pellets (99% purity and 20 mm, in diameter). The pellets were formed with a mixture of cellulose and a chemical compound containing the element of interest, pressed at 15 tons. The K X-rays emitted from the irradiated samples were detected by a Si(Li) detector with a frontal Pb collimator, coupled to conventional electronics, with dead time below 10%. The fluxes reaching the targets and the crystal detector were determined by means of Monte Carlo (MC) simulations using the MCNPX V 2.6 code. The input geometries included the detector, the sample-source holder and the Pb collimator. The optimal diameter for the samples as well as the collimator dimensions were estimated by means of MC simulations. Using several elements (Ti, Ni, Br, Ag, Cs, Dy and W) a calibration curve for the effective flux of photons (I{sub 0}G{sub {epsilon}}) as function of the K X-rays energy was measured. Correction by different sizes and self-absorption coefficients of the samples were also performed. The data obtained for the X-rays fluorescence cross sections were compared with semi-empirical calculations and with experimental values reported by other authors; the relative deviations were less than 10%. Keywords: fluorescence cross section, fluorescence yields, Monte Carlo (author)

  4. Improved energy of the 21.5 keV M1 + E2 nuclear transition in {sup 151}Eu

    Energy Technology Data Exchange (ETDEWEB)

    Inoyatov, A.Kh. [JINR, Laboratory of Nuclear Problems, Dubna, Moscow Region (Russian Federation); National University, Institute of Applied Physics, Tashkent (Uzbekistan); Kovalik, A. [JINR, Laboratory of Nuclear Problems, Dubna, Moscow Region (Russian Federation); Nuclear Physics Institute of the ASCR, Rez near Prague (Czech Republic); Filosofov, D.V.; Perevoshchikov, L.L. [JINR, Laboratory of Nuclear Problems, Dubna, Moscow Region (Russian Federation); Rysavy, M. [Nuclear Physics Institute of the ASCR, Rez near Prague (Czech Republic); Baimukhanova, A. [JINR, Laboratory of Nuclear Problems, Dubna, Moscow Region (Russian Federation); Institute of Nuclear Physics, Almaty (Kazakhstan)

    2016-05-15

    Using internal conversion electron spectroscopy, improved energy 21 541.5±0.5 eV was determined for the 21.5 keV M1+E2 nuclear transition in {sup 151}Eu populated in the electron capture decay of {sup 151}Gd. This value was found to agree well with the present adopted value but is much more accurate. A value of 0.0305±0.0011 derived for the E2 admixture parameter vertical stroke δ(E2/M1) vertical stroke from the measured conversion electron line intensities corresponds to the present adopted value. A possible effect of nuclear structure on the multipolarity of the 21.5 keV transition was also investigated. (orig.)

  5. Properties of the Plasma Surrounding the Global Heliosphere Determined with Voyager 1&2 ions and ENA/INCA Observations at E > 5 keV

    Science.gov (United States)

    Krimigis, S. M.; Dialynas, K.; Mitchell, D. G.; Decker, R. B.; Roelof, E. C.

    2016-12-01

    The basic goal of the proposed Interstellar Mapping and Acceleration Probe (IMAP) is detailed scientific understanding of the Heliosheath (HS) and beyond, a region of space explored in situ by Voyager 1 (V1) since 2004, Voyager 2 (V2) since 2007, and remotely via energetic neutral atoms (ENA) by the Cassini/INCA (5.2-55 keV) since 2003 and IBEX (0.3-6 keV) since 2009. The partial overlap in energies (28 5 keV, the rest residing below that range, resulting in a beta (particle/magnetic pressure) always > 1, typically >10. (2) Based on the ENA-derived hot ion pressures, the interstellar magnetic field (ISMF) was predicted to be more than twice that expected in the literature i.e. similar to what was measured by V1 after crossing the heliopause (B 0.5 nT). (3) The width of the HS in the direction of V1 is 30 AU (predicted by INCA before the V1 HP crossing), but is thought to be larger (40-70 AU) in the southern ecliptic where V2, now 30 AU into the HS, currently travels. We address here the key question of the source of 5-55 keV ENAs that INCA measures. The analysis of INCA all-sky maps from 2003 to 2014 show that the decrease and recovery of ENA in the global heliosphere during this period (declining phase of SC23 and rise of SC24) is similar to that of the ions at V1/V2, consistent with the HS ions being the source of ENA. The close correspondence between ENA and ion spectra (despite the 140 AU distance between V1 and V2) as well as the similarity of ENA spectra over the nose and anti-nose directions, together with the recent V1 measurement of a BISMF 0.5nT, suggest that the global distributions of >5 keV ions in the heliosheath resembles a diamagnetic bubble with no significant tail-like feature (the alternative Parker 1961 model), also consistent with some recent MHD simulations and models.

  6. Teflon impregnated anatase TiO{sub 2} nanoparticles irradiated by 80 keV Xe{sup +} ions

    Energy Technology Data Exchange (ETDEWEB)

    Khanam, Rizwin; Paul, Nibedita; Kumar, P.; Kanjilal, D.; Ahmed, Gazi A.; Mohanta, Dambarudhar, E-mail: best@tezu.ernet.in

    2014-10-01

    Highlights: •Nanoscale TiO{sub 2} exhibited swelling led particle growth due to low energy ion impact. •Formation of Xe crystals is likely to induce swelling behavior in titania. •Nanoripples are witnessed on the surface of nanoparticles. •Manifested band edge and oxygen vacancy related optical emissions have been revealed. -- Abstract: We report the effect of 80 keV Xe{sup +} ion irradiation on the morphological and optical responses of TiO{sub 2} nanoparticles spread over commercially available polytetrafluoroethylene (PTFE, Teflon). These nanoparticles were synthesized via a convenient, sol–gel approach with titanium isopropoxide as the main precursor. From X-ray diffraction (XRD) studies we found that, the nanoparticles crystallize in anatase phase and with a preferential orientation of crystallites along (1 0 1) plane. Upon irradiation at a fluence of 1.25 × 10{sup 17} ions/cm{sup 2}, the nanoparticle dimension was found to increase from a value of ∼9 nm to ∼20–30 nm. Essentially, particle growth is predicted as a consequence of swelling behavior accompanied by the formation of Xe van der Waal crystals in isolated regions of nano-titania. Evidence of nanoripples was also witnessed on the surface of the irradiated nano-titania. The morphological evolution was assessed both by atomic force and transmission electron microscopies (AFM and TEM) independently. From the UV–Vis optical absorption studies, the estimated optical band gap was found to drop with increasing fluence, while refractive index exhibited a remarkable improvement. Photoluminescence (PL) studies have revealed that, the band edge emission and those due to the self trapped excitons (STE) and other oxygen vacancy related ones were manifested considerably as a result of Xe ion irradiation.

  7. High accuracy measurement of the $^{235}$U(n,f) reaction cross-section in the 10-30 keV neutron energy range

    CERN Multimedia

    The analysis of the neutron flux of n_TOF (in EAR1) revealed an anomaly in the 10-30 keV neutron energy range. While the flux extracted on the basis of the $^{6}$Li(n,t)$^{4}$He and $^{10}$B(n,$\\alpha$)$^{7}$Li reactions mostly agreed with each other and with the results of FLUKA simulations of the neutron beam, the one based on the $^{235}$U(n,f) reaction was found to be systematically lower, independently of the detection system used. A possible explanation is that the $^{235}$U(n,f) crosssection in that energy region, where in principle should be known with an uncertainty of 1%, may be systematically overestimated. Such a finding, which has a negligible influence on thermal reactors, would be important for future fast critical or subcritical reactors. Furthermore, its interest is more general, since the $^{235}$U(n,f) reaction is often used at that energy to determine the neutron flux, or as reference in measurements of fission cross section of other actinides. We propose to perform a high-accuracy, high-r...

  8. Developing a Compton Polarimeter to Measure Polarization of Hard X-Rays in the 50-300 keV Energy Range

    CERN Document Server

    Legere, J S; Macri, J R; McConnell, M L; Narita, T; Ryan, J M

    2005-01-01

    This paper discusses the latest progress in the development of GRAPE (Gamma-Ray Polarimeter Experiment), a hard X-ray Compton Polarimeter. The purpose of GRAPE is to measure the polarization of hard X-rays in the 50-300 keV energy range. We are particularly interested in X-rays that are emitted from solar flares and gamma-ray bursts (GRBs). Accurately measuring the polarization of the emitted radiation from these sources will lead, to a better understating of both the emission mechanisms and source geometries. The GRAPE design consists of an array of plastic scintillators surrounding a central high-Z crystal scintillator. We can monitor individual Compton scatters that occur in the plastics and determine whether the photon is photo absorbed by the high-Z crystal or not. A Compton scattered photon that is immediately photo absorbed by the high-Z crystal constitutes a valid event. These valid events provide us with the interaction locations of each incident photon and ultimately produces a modulation pattern fo...

  9. LAPSI 2.0

    DEFF Research Database (Denmark)

    Lundqvist, Björn; Forsberg, Yrsa; de Vries, Marc

    The efforts of the European Commission are paying off: increasingly governments all over Europe are opening up their data, often without charging for the re-use. This in perfect sync with the spirit and mission of the 2003 and, in particular, 2013 PSI Directives, which both advocate free......, harming their commercial interests. They argue that by opening up their PSI these governments are conducting unfair competition practices, or at least inflicting damage. This claim merits deeper consideration: if these incumbent players are right, this could impact adoption of Open Data policies...... by governments throughout Europe and in fact frustrate the sound application of the PSI Directive. A possible collision of the PSI Directive and European competition (law) principles – The LAPSI 2.0 Network has adopted it as the subject of a position paper under WP 3 (IP and competition law). The paper...

  10. BPMN2.0

    Institute of Scientific and Technical Information of China (English)

    潘加宇

    2010-01-01

    OMG已经通过Business Process Modeling Notation(BPMN)2.0规格的beta版本,最后的版本预计将于2010年通过。BPMN在过去几年内的采纳率增长得很快,因为它比较简单,容易上手。不过,BPMN1.x只是提供了业务流程建模的图形符号,没有定义交换格式以保证用户在不同厂商的BPMN工具之间以标准方式交换模型,

  11. COCO, a Compton coincidence experiment to study liquid scintillator response in the 1-20 keV energy range

    Energy Technology Data Exchange (ETDEWEB)

    Peron, M.N. (Laboratoire Primaire des Rayonnements Ionisants, CEA/DAMRI, CE Saclay, BP 52, 91193 Gif-sur-Yvette Cedex (France)); Cassette, P. (Laboratoire Primaire des Rayonnements Ionisants, CEA/DAMRI, CE Saclay, BP 52, 91193 Gif-sur-Yvette Cedex (France))

    1994-12-30

    The use of Liquid Scintillation Counting (LSC) as a fundamental radionuclide standardisation method requires a correct description of the physical phenomena occurring during the LSC process. In that framework, a special point of interest is the description of the liquid scintillator response, especially for low-energy electrons, in a region where this response is known to be non-linear. As there is no simple way to produce monoenergetic electrons in the liquid scintillator, we have simulated these electrons using a Compton interaction coincidence method. Due to the energy conservation law, the selection of the energy of the scattered Compton X-ray photon is equivalent to the selection of the energy of a monoenergetic electron. This paper describes the experimental system and the methods used to analyse the experimental results in order to deduce the statistical distribution of the photons emitted by the scintillator. The effects of some artefacts are discussed, including the accidental coincidences and the influence of cascade Compton interactions. ((orig.))

  12. Developing a Compton polarimeter to measure polarization of hard x-rays in the 50-300 keV energy range

    Science.gov (United States)

    Legere, Jason; Bloser, Peter L.; Macri, John R.; McConnell, Mark L.; Narita, Tomohiko; Ryan, James M.

    2005-08-01

    This paper discusses the latest progress in the development of GRAPE (Gamma-Ray Polarimeter Experiment), a hard X-ray Compton Polarimeter. The purpose of GRAPE is to measure the polarization of hard X-rays in the 50-300 keV energy range. We are particularly interested in X-rays that are emitted from solar flares and gamma-ray bursts (GRBs). Accurately measuring the polarization of the emitted radiation from these sources will lead, to a better understating of both the emission mechanisms and source geometries. The GRAPE design consists of an array of plastic scintillators surrounding a central high-Z crystal scintillator. We can monitor individual Compton scatters that occur in the plastics and determine whether the photon is photo absorbed by the high-Z crystal or not. A Compton scattered photon that is immediately photo absorbed by the high-Z crystal constitutes a valid event. These valid events provide us with the interaction locations of each incident photon and ultimately produces a modulation pattern for the Compton scattering of the polarized radiation. Comparing with Monte Carlo simulations of a 100% polarized beam, the level of polarization of the measured beam can then be determined. The complete array is mounted on a flat-panel multi-anode photomultiplier tube (MAPMT) that can measure the deposited energies resulting from the photon interactions. The design of the detector allows for a large field-of-view, at the same time offering the ability to be close-packed with multiple modules in order to reduce deadspace. We plan to present in this paper the latest laboratory results obtained from GRAPE using partially polarized radiation sources.

  13. Correlation between electrical transport, microstructure and room temperature ferromagnetism in 200 keV Ni{sup 2+} ion implanted zinc oxide (ZnO) thin films

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, B. [Gautam Buddha University, Department of Applied Sciences, Greater Noida (India); Ghosh, S.; Srivastava, P. [Indian Institute of Technology Delhi, Nanostech Laboratory, New Delhi (India); Kumar, P.; Kanjilal, D. [Aruna Asaf Ali Marg, Inter University Accelerator Centre, New Delhi (India)

    2012-05-15

    We report variable temperature resistivity measurements and mechanisms related to electrical conduction in 200 keV Ni{sup 2+} ion implanted ZnO thin films deposited by vapor phase transport. The dc electrical resistivity versus temperature curves show that all polycrystalline ZnO films are semiconducting in nature. In the room temperature range they exhibit band conduction and conduction due to thermionic emission of electrons from grain boundaries present in the polycrystalline films. In the low temperature range, nearest neighbor hopping (NNH) and variable range hopping (VRH) conduction are observed. The detailed conduction mechanism of these films and the effects of grain boundary (GB) barriers on the electrical conduction process are discussed. An attempt is made to correlate electrical conduction behavior and previously observed room temperature ferromagnetism of these films. (orig.)

  14. Linear and nonlinear transmission of Fe{sup 2+}-doped ZnSe crystals at a wavelength of 2940 nm in the temperature range 20–220 °C

    Energy Technology Data Exchange (ETDEWEB)

    Il' ichev, N N; Pashinin, P P; Gulyamova, E S; Bufetova, G A [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Shapkin, P V; Nasibov, A S [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2014-03-28

    The linear and nonlinear transmission of Fe{sup 2+}:ZnSe crystals is measured at a wavelength of 2940 nm in the temperature range 20 – 220 °C. It is found that, with increasing temperature from 20 °C to 150 – 220 °C, the transmission of Fe{sup 2+}:ZnSe crystals decreases in the case of incident radiation with an intensity of ∼5.5 MW cm{sup -2} and increases in the case of radiation with an intensity of 28 kW cm{sup -2}. At a temperature of 220 °C, the linear transmission almost coincides with the nonlinear transmission. The transmission spectra of Fe{sup 2+}:ZnSe crystals at temperatures of 22 and 220 °C in the wavelength range 500 – 7000 nm are presented. (active media)

  15. Xenopatients 2.0

    Science.gov (United States)

    Menendez, Javier A; Alarcón, Tomás; Corominas-Faja, Bruna; Cuyàs, Elisabet; López-Bonet, Eugeni; Martin, Ángel G; Vellon, Luciano

    2014-01-01

    stemness factors following the activation of phenotypic copies of specific cancer diseases might crucially evaluate a “reprogramming cure” for cancer. A new era of xenopatients 2.0 generated via nuclear reprogramming of the epigenetic landscapes of patient-derived cancer genomes might revolutionize the current personalized translational platforms in cancer research. PMID:24406535

  16. The half-life of the 1437 keV 11/2 sup - state in sup 97 Mo

    Energy Technology Data Exchange (ETDEWEB)

    Kostova, L.G.; Andrejtscheff, W.; Kostov, L.K. (Bylgarska Akademiya na Naukite, Sofia (Bulgaria). Inst. za Yadrena Izsledvaniya i Yadrena Energetika); Funke, L.; Will, E. (Zentralinstitut fuer Kernforschung, Rossendorf (Germany)); Vdovin, A.I. (Joint Inst. for Nuclear Research, Dubna (Russia))

    1992-05-01

    Using the ({alpha}, n) reaction, the half-life of the first 11/2{sup -} level in {sup 97}Mo has been determined as T{sub 1/2}(1437.0 keV)=2.5{+-}0.3 ns by means of the pulsed beam method. The experimentally obtained B(M2) value between the h{sub 11/2} and g{sub 7/2} configurations in {sup 97}Mo has been satisfactorily described within the quasiparticle-phonon model using g{sub s}{sup eff}=0.6 g{sub s}{sup free} c{sub s}. Similar calculations and comparisons with experimental data have been performed also for {sup 95,99}Mo as well as for {sup 99}Ru and {sup 101}Pd. (orig.).

  17. Measurement of neutron capture cross section of sup 1 sup 7 sup 4 Hf in the energy range from 162 to 1200 keV

    CERN Document Server

    Xia Yi Jun; Yang Zhi Hua

    2001-01-01

    The cross sections for the sup 1 sup 7 sup 4 Hf( n, gamma) sup 1 sup 7 sup 5 Hf reaction were measured relatively to the sup 1 sup 9 sup 7 Au(n, gamma) sup 1 sup 9 sup 8 Au reaction for neutron energies from 162 to 1200 keV, using the activation technique with high resolution HPGE gamma ray spectroscopy. Some experimental data were given for the first time

  18. Web 2.0 aplikace

    OpenAIRE

    Lednický, Miroslav

    2008-01-01

    Following pages will be about abounded term "Web 2.0". I will try to explain the core characteristics of "Web 2.0" applications. This explanation will be followed by some existing examples of these applications. Main target is to explain the term "Web 2.0".

  19. Sputtering of SiN films by 540 keV C{sub 60}{sup 2+} ions observed using high-resolution Rutherford backscattering spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, K.; Morita, Y.; Kitayama, T.; Suzuki, M. [Department of Micro Engineering, Kyoto University, Kyoto 615-8540 (Japan); Narumi, K.; Saitoh, Y. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gumma 370-1292 (Japan); Tsujimoto, M.; Isoda, S. [Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto 606-8501 (Japan); Fujii, Y. [Center for Supports to Research and Education Activities, Kobe University, Kobe 657-8501 (Japan); Kimura, K., E-mail: kimura@kues.kyoto-u.ac.jp [Department of Micro Engineering, Kyoto University, Kyoto 615-8540 (Japan)

    2014-08-01

    Amorphous silicon nitride films deposited on Si(0 0 1) were irradiated with 540 keV C{sub 60} ions to fluences ranging from 2.5 × 10{sup 11} to 1 × 10{sup 14} ions/cm{sup 2}. The composition depth profiles of the irradiated samples were measured using high-resolution Rutherford backscattering spectroscopy. Both silicon and nitrogen in the film decrease rapidly with fluence. From the observed result the sputtering yields are obtained as 3900 ± 500 N atoms/ion and 1500 ± 1000 Si atoms/ion. Such large sputtering yield cannot be explained by either the elastic sputtering or the electronic sputtering, indicating that the synergy effect between the elastic sputtering and the electronic sputtering plays an important role.

  20. Web 2.0

    Institute of Scientific and Technical Information of China (English)

    胡泳

    2007-01-01

    Web 2.0是现在媒体上常见的名词,但究竟什么是Web 2.0?这个术语的始作俑者蒂姆·欧内利是这样定义的:“Web 2.0指网络作为平台,横跨所有互联设备;Web 2.0应用充分调动这一平台的内在优势:把软件作为不断升级的服务加以提供,使用软件的人越多,软件变得越好;这些应用从多种来源(包括个人用户)吸取和重混数据,与此同时,允许自己的数据和服务被他人重混。”这个定义由于技术化而显得晦涩难解。在另一处,欧内利举例

  1. UNIVERSITET 2.0?

    DEFF Research Database (Denmark)

    Sarauw, Laura Louise

    2011-01-01

    Universitetsloven fra 2003 understreger som noget nyt, at universiteterne ved siden af de traditionelle forpligtelser på forskning og undervisning også skal ‘udveksle viden og kompetencer med det omgivende samfund’ (2003¿2). I de almindelige bemærkninger til loven indskærpes samtidig, at uddannel...

  2. Analytic Morse/long-range potential energy surfaces and predicted infrared spectra for CO-H2 dimer and frequency shifts of CO in (para-H2)N N = 1-20 clusters

    Science.gov (United States)

    Li, Hui; Zhang, Xiao-Long; Le Roy, Robert J.; Roy, Pierre-Nicholas

    2013-10-01

    A five-dimensional ab initio potential energy surface (PES) for CO-H2 that explicitly incorporates dependence on the stretch coordinate of the CO monomer has been calculated. Analytic four-dimensional PESs are obtained by least-squares fitting vibrationally averaged interaction energies for vCO = 0 and 1 to the Morse/long-range potential function form. These fits to 30 206 points have root-mean-square (RMS) deviations of 0.087 and 0.082 cm-1, and require only 196 parameters. The resulting vibrationally averaged PESs provide good representations of the experimental infrared data: for infrared transitions of para H2-CO and ortho H2-CO, the RMS discrepancies are only 0.007 and 0.023 cm-1, which are almost in the same accuracy as those values of 0.010 and 0.018 cm-1 obtained from full six-dimensional ab initio PESs of V12 [P. Jankowski, A. R. W. McKellar, and K. Szalewicz, Science 336, 1147 (2012)]. The calculated infrared band origin shift associated with the fundamental of CO is -0.179 cm-1 for para H2-CO, which is the same value as that extrapolated experimental value, and slightly better than the value of -0.176 cm-1 obtained from V12 PESs. With these potentials, the path integral Monte Carlo algorithm and a first order perturbation theory estimate are used to simulate the CO vibrational band origin frequency shifts of CO in (para H2)N-CO clusters for N = 1-20. The predicted vibrational frequency shifts are in excellent agreement with available experimental observations. Comparisons are also made between these model potentials.

  3. 20.2.Infection

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    930385 Determination of serum sialic acidphospholipid and cholesterol and its clinical sig-nificance in patients with Guillain-Barre syn-drome.ZHANG Xiangjian (张祥建),et al.DeptNeurol,2nd Affil Hosp,Hebei Med Coil,Shiji-azhuang,050000.Chin J Nerv & Merit Dis 1992;18(5):271—273.Serum sialie acid (SA) level was measured inthe patients with Guillain-Barre syndrome(GBS) and normal controls.The results showedthat the serum SA level (788.1±23.8mg/L) in51 of patients with GBS was significantly higherthan that(538.1±8.9mg/L) in 50 normal con-trols (P<0.001).The positivity of serum SA inthe patients (36/51) was significantly higherthan that in normal controls (3/50,P<0.001).

  4. Differential cross sections for the single ionization of H2 by 75 keV proton impact

    Science.gov (United States)

    Igarashi, A.; Gulyás, L.

    2017-02-01

    We have calculated the double and triple differential cross sections for electron ejection with energy of 14.6 eV in single ionization of H2 by 75 keV proton impact. A molecular version of the continuum distorted wave-eikonal initial state approach is applied, where the interaction between the projectile and the residual molecular ion is considered more properly than in previous applications of the method. For triple differential cross sections, the present results are in better agreement with the experimental data than those of other descriptions when large momentum transfer values are considered. For double differential cross sections the experimental data are reproduced quite well for both coherent and incoherent proton beams.

  5. Dense ion clouds of 0.1 − 2 keV ions inside the CPS-region observed by Astrid-2

    Directory of Open Access Journals (Sweden)

    O. Norberg

    Full Text Available Data from the Astrid-2 satellite taken between April and July 1999 show several examples of dense ion clouds in the 0.1–2 keV energy range inside the inner mag-netosphere, both in the northern and southern hemispheres. These inner magnetospheric ion clouds are found predomi-nantly in the early morning sector, suggesting that they could have originated from substorm-related ion injections on the night side. However, their location and density show no cor-relation with Kp, and their energy-latitude dispersion is not easily reproduced by a simple particle drift model. There-fore, these ion clouds are not necessarily caused by substorm-related ion injections. Alternative explanations for the ion clouds are the direct solar wind injections and up-welling ions from the other hemisphere. These explanations do not, however, account for all of the observations.Key words. Magnetospheric physics (energetic particles, trapped; magnetospheric configuration and dynamics; storm and substorms

  6. Fine pitch CdTe-based Hard-X-ray polarimeter performance for space science in the 70-300 keV energy range

    CERN Document Server

    Antier, S; Ferrando, P

    2015-01-01

    X-rays astrophysical sources have been almost exclusively characterized through imaging, spectroscopy and timing analysis. Nevertheless, more observational parameters are needed because some radiation mechanisms present in neutrons stars or black holes are still unclear. Polarization measurements will play a key role in discrimination between different X-ray emission models. Such a capability becomes a mandatory requirement for the next generation of high-energy space proposals. We have developed a CdTe-based fine-pitch imaging spectrometer, Caliste, able to respond to these new requirements. With a 580-micron pitch and 1 keV energy resolution at 60 keV, we are able to accurately reconstruct the polarization angle and polarization fraction of an impinging flux of photons which are scattered by 90{\\deg} after Compton diffusion within the crystal. Thanks to its high performance in both imaging and spectrometry, Caliste turns out to be a powerful device for high-energy polarimetry. In this paper, we present the ...

  7. Critical currents of superconducting BiPbSrCaCuO tapes in the magnetic flux density range 0--19. 75 T at 4. 2, 15, and 20 K

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K.; Hikata, T. (Osaka Research Laboratories, Sumitomo Electric Industries, Osaka (Japan)); Iwasa, Y. (Francis Bitter National Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA (USA))

    1990-10-29

    Critical currents of superconducting silver-sheathed tapes of Bi{sub 1.8}Pb{sub 0.4}Sr{sub 2}Ca{sub 2.2}Cu{sub 3}O{sub {ital x}} have been measured in the magnetic flux density range 0--19.75 T at 4.2, 15, and 20 K. One tape achieved a critical current of 60.6 A at 19.75 T and 20 K; the corresponding critical current density is 551 A/mm{sup 2}. In the same field, the tape has critical currents of 72.3 A (657 A/mm{sup 2}) at 15 K and 94.2 A (856 A/mm{sup 2}) at 4.2 K. At 77 K and in zero field, the tape carries 32.9 A (299 A/mm{sup 2}). These results indicate that high {ital T}{sub {ital c}}'' superconducting magnets of engineering interest may soon be feasible.

  8. SMM observations of gamma-ray transients. 2: A search for gamma-ray lines between 400 and 600 keV from the Crab Nebula

    Science.gov (United States)

    Harris, Michael J.; Share, Gerald H.; Leising, Mark D.

    1994-01-01

    We have search spectra obtained by the Solar Maximum Mission Gamma-Ray Spectrometer during 1981-1988 for evidence of transient gamma-ray lines from the Crab Nebula which have been reported by previous experiments at energies 400-460 keV and 539 keV. We find no evidence for significant emission in any of these lines on time scales between aproximately 1 day and approximately 1 yr. Our 3 sigma upper limits on the transient flux during 1 d intervals are approximately equal to 2.2 x 10(exp -3) photons/sq cm/s for narrow lines at any energy, and approximately equal to 2.9 x 10(exp -3) photons/sq cm/s for the 539 keV line if it is as broad as 42 keV Full Width at Half Maximum (FWHM). We also searched our data during the approximately 5 hr period on 1981 June 6 during which Owens, Myers, & Thompson (1985) reported a strong line at 405 keV. We detected no line down to a 3 upper sigma limit of 3.3 x 10(exp -3) photons/sq cm/s in disagreement with the flux 7.2 +/- 2.1 x 10(exp -3) photos/sq cm/s measured by Owens et al.

  9. Electron transport simulation in the range 1 keV-4 MeV for the purpose of high-resolution dosimetric application

    Energy Technology Data Exchange (ETDEWEB)

    Cobut, V. [Univ. de Cergy-Pontoise, Neuville/Oise (France). Lab. Pharmacophores Redox, Phytochimie et Radiobiologie; Cirioni, L.; Patau, J.P. [Univ. Paul Sabatier, Toulouse (France). Faculte de Pharmacie

    2001-07-01

    Experimental spectrometry and dosimetry can offer some reliable answers. However, they are not easy to implement in some specific situations. Furthermore, information on dose distributions cannot always be obtained with the desirable geometrical resolution. A way to get rid of these disadvantages consist in simulating every successive individual interactions suffered by electrons and photons along their path. We applied this principle to simulate the response of a detector placed in the field of beta-gamma sources, which maximum energy does not exceed 4 MeV. A part of this work is presented here, which concerns Monte Carlo simulation of electron transport in materials encountered in experimental dosimetric devices. Electrons were followed down to a cutoff energy of 1 keV. (orig.)

  10. The 1 keV to 200 keV X-ray Spectrum of NGC 2992 and NGC 3081

    CERN Document Server

    Beckmann, Volker; Tueller, Jack

    2007-01-01

    The Seyfert 2 galaxies NGC 2992 and NGC 3081 have been observed by INTEGRAL and Swift. We report about the results and the comparison of the spectrum above 10 keV based on INTEGRAL IBIS/ISGRI, Swift/BAT, and BeppoSAX/PDS. A spectrum can be extracted in the X-ray energy band ranging from 1 keV up to 200 keV. Although NGC 2992 shows a complex spectrum below 10 keV, the hard tail observed by various missions exhibits a slope with photon index = 2, independent on the flux level during the observation. No cut-off is detectable up to the detection limit around 200 keV. In addition, NGC 3081 is detected in the INTEGRAL and Swift observation and also shows an unbroken Gamma = 1.8 spectrum up to 150 keV. These two Seyfert galaxies give further evidence that a high-energy cut-off in the hard X-ray spectra is often located at energies E_C >> 100 keV. In NGC 2992 a constant spectral shape is observed over a hard X-ray luminosity variation by a factor of 11. This might indicate that the physical conditions of the emitting...

  11. Neutron cross section evaluations of europium isotopes in 1 keV - 30 MeV energy range. Format - validation - comparison; Evaluation de sections efficaces pour des neutrons incidents sur des isotopes d'europium aux energies 1 keV - 30 MeV. Format - validation - comparaison

    Energy Technology Data Exchange (ETDEWEB)

    Dossantos-Uzarralde, P.; Le Luel, C.; Bauge, E. [CEA Bruyeres le Chatel, 91 (France). Dept. de Physique Theorique et Appliquee

    2004-07-01

    This paper presents neutron cross section evaluations of Europium isotopes. The cross sections are evaluated in 1 keV - 30 MeV energy range for the isotopes {sup 146}Eu, {sup 147}Eu, {sup 148}Eu, {sup 149}Eu, {sup 150}Eu, {sup 151}Eu, {sup 152}Eu, {sup 153}Eu, {sup 154}Eu in their ground state. This evaluation includes cross section productions of the long life isomeric states. Special attention is put on the options used for the description of the files written in ENDF-6 format. The final issue is a proposal of a new breed of ENDF-6 formatted neutron activation file. (authors)

  12. Compact Source of Electron Beam with Energy of 200 kEv and Average Power of 2 kW

    CERN Document Server

    Kazarezov, Ivan; Balakin, Vladimir E; Bryazgin, Alex; Bulatov, Alexandre; Glazkov, Ivan; Kokin, Evgeny; Krainov, Gennady; Kuznetsov, Gennady I; Molokoedov, Andrey; Tuvik, Alfred

    2005-01-01

    The paper describes a compact electron beam source with average electron energy of 200 keV. The source operates with pulse power up to 2 MW under average power not higher than 2 kW, pulsed beam current up to 10 A, pulse duration up to 2 mks, and repetition rate up to 5 kHz. The electron beam is extracted through aluminium-beryllium alloy foil. The pulse duration and repetition rate can be changed from control desk. High-voltage generator for the source with output voltage up to 220 kV is realized using the voltage-doubling circuit which consists of 30 sections. The insulation type - gas, SF6 under pressure of 8 atm. The cooling of the foil supporting tubes is provided by a water-alcohol mixture from an independent source. The beam output window dimensions are 180?75 mm, the energy spread in the beam +10/-30%, the source weight is 80 kg.

  13. A photoluminescence study of CuInSe2 single crystals ion implanted with 5 keV hydrogen

    Science.gov (United States)

    Yakushev, M. V.; Krustok, J.; Grossberg, M.; Volkov, V. A.; Mudryi, A. V.; Martin, R. W.

    2016-03-01

    CuInSe2 single crystals ion implanted with 5 keV hydrogen at doses from 3  ×  1014 to 1016 cm-2 are studied by photoluminescence (PL). The PL spectra before and after implantation reveal two bands, a main dominant band centred at 0.96 eV and a lower intensity band centred at 0.93 eV. Detailed analysis of the shape of these bands, their temperature and excitation intensity dependencies allow the recombination mechanisms to be identified as band-to-tail (BT) and band-to-impurity (BI), respectively. The implantation causes gradual red shifts of the bands increasing linearly with the dose. The average depth of potential fluctuations is also estimated to increase with the dose and saturates for doses above 1015 cm-2. A model is proposed which associates the potential fluctuations with the antisite defects copper on indium site and indium on copper site. The saturation is explained by full randomization of copper and indium atoms on the cation sub-lattice.

  14. Electron-Impact Ionization Cross Sections of H, He, N, O, Ar, Xe, Au, Pb Atoms and Their Ions in the Electron Energy Range from the Threshold up to 200 keV

    CERN Document Server

    Povyshev, V M; Shevelko, V P; Shirkov, G D; Vasina, E G; Vatulin, V V

    2001-01-01

    Single electron-impact ionization cross sections of H, He, N, O, Ar, Xe, Au, Pb atoms and their positive ions (i.e. all ionization stages) are presented in the electron energy range from the threshold up to 200 keV. The data-set for the cross sections has been created on the basis of available experimental data and calculations performed by the computer code ATOM. Consistent data for the ionization cross sections have been fitted by seven parameters using the LSM method. The accuracy of the calculated data presented is within a factor of 2 that in many cases is sufficient to solve the plasma kinetics problems. Contributions from excitation-autoionization and resonant-ionization processes as well as ionization of atoms and ions are not considered here. The results of the numerical calculations are compared with the well-known Lotz formulae for ionization of neutral atoms and positive ions. The material is illustrated by figures and includes tables of ionization cross sections, binding energies and fitting para...

  15. Experimental Set-up for Irradiation of Solid H2 and D2 with Charged Particles of keV Energies

    DEFF Research Database (Denmark)

    Sørensen, H.

    1976-01-01

    An experimental facility was built where films of solid deuterium (and hydrogen) may be made with known thickness and irradiated with pulsed beams of electrons (up to 3 keV) and light ions (up to 10 keV). Films are made on a target plate held at 2.5–3 K. Film growth rate is calibrated with a quartz...... crystal film thickness monitor. The target plate, which can be heated so that films are removable by evaporation, may be used both as a calorimeter and as a beam current collector. Methods for measurement of secondary electron emission coefficients were developed, and preliminary measurements were made......-reflection coefficient γ (i.e. the fraction of beam energy reflected from the target) for protons impinging on a heavy target material by using the target as a calorimeter....

  16. Sputtering of thin and intermediately thick films of solid deuterium by keV electrons

    DEFF Research Database (Denmark)

    Svendsen, Winnie Edith; Thestrup Nielsen, Birgitte; Schou, Jørgen

    1995-01-01

    Sputtering of films of solid deuterium by keV electrons was studied in a cryogenic set-up. The sputtering yield shows a minimum yield of about 4 D2/electron for 1.5 and 2 keV electrons at a thickness slightly larger than the average projected range of the electrons. We suggest that the yield around...

  17. Variation in the calibrated response of LiF, Al2O3, and silicon dosimeters when used for in-phantom measurements of source photons with energies between 30 KeV AND 300 KeV.

    Science.gov (United States)

    Poudel, Sashi; Currier, Blake; Medich, David C

    2015-04-01

    The MCNP5 radiation transport code was used to quantify changes in the absorbed dose conversion factor for LiF, Al2O3, and silicon-based electronic dosimeters calibrated in-air using standard techniques and summarily used to measure absorbed dose to water when placed in a water phantom. A mono-energetic photon source was modeled at energies between 30 keV and 300 keV for a point-source placed at the center of a water phantom, a point-source placed at the surface of the phantom, and for a 10-cm radial field geometry. Dosimetric calculations were obtained for water, LiF, Al2O3, and silicon at depths of 0.2 cm and 10 cm from the source. These results were achieved using the MCNP5 *FMESH photon energy-fluence tally, which was coupled with the appropriate DE/DF card for each dosimetric material studied to convert energy-fluence into the absorbed dose. The dosimeter's absorbed dose conversion factor was calculated as a ratio of the absorbed dose to water to that of the dosimeter measured at a specified phantom depth. The dosimeter's calibration value also was obtained. Based on these results, the absorbed dose conversion factor for a LiF dosimeter was found to deviate from its calibration value by up to 9%, an Al2O3 dosimeter by 43%, and a silicon dosimeter by 61%. These data therefore can be used to obtain LiF, Al2O3, and silicon dosimeter correction factors for mono-energetic and poly-energetic sources at measurement depths up to 10 cm under the irradiation geometries investigated herein.

  18. Cross-field diffusion of energetic (100 keV to 2 MeV) protons in interplanetary space

    Energy Technology Data Exchange (ETDEWEB)

    Costa Jr, Edio da [Instituto Federal de Minas Gerais-IFMG, Ouro Preto, MG, 35400-000 (Brazil); Tsurutani, Bruce T. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Alves, Maria Virgínia; Echer, Ezequiel [Instituto Nacional de Pesquisas Espaciais-INPE, São José dos Campos, SP, 12227-010 (Brazil); Lakhina, Gurbax S., E-mail: edio.junior@ifmg.edu.br, E-mail: costajr.e@gmail.com [Indian Institute for Geomagnetism, Navi Mumbai 410 218 (India)

    2013-12-01

    Magnetic field magnitude decreases (MDs) are observed in several regions of the interplanetary medium. In this paper, we characterize MDs observed by the Ulysses spacecraft instrumentation over the solar south pole by using magnetic field data to obtain the empirical size, magnetic field MD, and frequency of occurrence distribution functions. The interaction of energetic (100 keV to 2 MeV) protons with these MDs is investigated. Charged particle and MD interactions can be described by a geometrical model allowing the calculation of the guiding center shift after each interaction. Using the distribution functions for the MD characteristics, Monte Carlo simulations are used to obtain the cross-field diffusion coefficients as a function of particle kinetic energy. It is found that the protons under consideration cross-field diffuse at a rate of up to ≈11% of the Bohm rate. The same method used in this paper can be applied to other space regions where MDs are observed, once their local features are well known.

  19. A new international geostationary electron model: IGE-2006, from 1 keV to 5.2 MeV

    Science.gov (United States)

    Sicard-Piet, A.; Bourdarie, S.; Boscher, D.; Friedel, R. H. W.; Thomsen, M.; Goka, T.; Matsumoto, H.; Koshiishi, H.

    2008-07-01

    Département Environnement Spatial, Office National d'Etudes et de Recherches Aérospatiales (ONERA) has been developing a model for the geostationary electron environment since 2003. Until now, this model was called Particle ONERA-LANL Environment (POLE), and it is valid from 30 keV up to 5.2 MeV. POLE is based on the full complement of Los Alamos National Laboratory geostationary satellites, covers the period 1976-2005, and takes into account the solar cycle variation. Over the period 1976 to present, four different detectors were flown: charged particle analyzer (CPA), synchronous orbit particle analyzer (SOPA), energetic spectra for particles (ESP), and magnetospheric plasma analyzer (MPA). Only the first three were used to develop the POLE model. Here we extend the energy coverage of the model to low energies using MPA measurements. We further include the data from the Japanese geostationary spacecraft, Data Relay Test Satellite (DRTS). These data are now combined into an extended geostationary electron model which we call IGE-2006.

  20. High-efficiency B₄C/Mo₂C alternate multilayer grating for monochromators in the photon energy range from 0.7 to 3.4 keV.

    Science.gov (United States)

    Choueikani, Fadi; Lagarde, Bruno; Delmotte, Franck; Krumrey, Michael; Bridou, Françoise; Thomasset, Muriel; Meltchakov, Evgueni; Polack, François

    2014-04-01

    An alternate multilayer (AML) grating has been prepared by coating an ion etched lamellar grating with a B4C/Mo2C multilayer (ML) having a layer thickness close to the groove depth. Such a structure behaves as a 2D synthetic crystal and can reach very high efficiencies when the Bragg condition is satisfied. This AML coated grating has been characterized at the SOLEIL Metrology and Tests Beamline between 0.7 and 1.7 keV and at the four-crystal monochromator beamline of Physikalisch-Technische Bundesanstalt (PTB) at BESSY II between 1.75 and 3.4 keV. A peak diffraction efficiency of nearly 27% was measured at 2.2 keV. The measured efficiencies are well reproduced by numerical simulations made with the electromagnetic propagation code CARPEM. Such AML gratings, paired with a matched ML mirror, constitute efficient monochromators for intermediate energy photons. They will extend the accessible energy for many applications as x-ray absorption spectroscopy or x-ray magnetic circular dichroism experiments.

  1. Grey Literature 2.0

    OpenAIRE

    Simandlová, Tereza

    2012-01-01

    The paper tries to describe grey literature in the context of platforms and tools of the web 2.0. We can follow up that increasing trends in the scientific communication are e.g. microblogging, scientific blogging and there are also scientific social networks in the distribution cycle of grey literature. Except the examples of grey literature 2.0, the paper also discusses the problems of the promotion of grey literature and grey literature community through the social media.

  2. Proton induced K X-ray production cross sections of the elements Al, Si, Ti, Fe, and Ni in the 0.7–2.0 MeV energy range

    Energy Technology Data Exchange (ETDEWEB)

    Bertol, Ana Paula Lamberti [Programa de Pós Graduação em Física, PPGFis, Universidade Federal do Rio Grande do Sul, UFRGS, Porto Alegre, RS (Brazil); Hinrichs, Ruth [PPGFis and Instituto de Geociências, UFRGS (Brazil); Vasconcellos, Marcos A.Z. [PPGFis and Instituto de Física, UFRGS (Brazil)

    2015-12-15

    Proton induced K-shell ionization cross sections were obtained for the elements Al, Si, Ti, Fe, and Ni in the 0.7–2.0 MeV energy range. The accuracy of these fundamental parameters is essential for PIXE analysis and the data in the literature present a considerable spread, mainly for Al and Si. The values obtained for Ti, Fe and Ni are compatible with the current theories and the experimental results reported in the literature. However, Al and Si cross sections present important differences from theoretical and experimental data. We propose values for the fluorescent yields of Al and Si that are compatible with recent results and can be incorporated in the computations of K X-ray production cross sections.

  3. Interferometric phase-contrast X-ray CT imaging of VX2 rabbit cancer at 35keV X-ray energy

    Science.gov (United States)

    Takeda, Tohoru; Wu, Jin; Tsuchiya, Yoshinori; Yoneyama, Akio; Lwin, Thet-Thet; Hyodo, Kazuyuki; Itai, Yuji

    2004-05-01

    Imaging of large objects at 17.7-keV low x-ray energy causes huge x-ray exposure to the objects even using interferometric phase-contrast x-ray CT (PCCT). Thus, we tried to obtain PCCT images at high x-ray energy of 35keV and examined the image quality using a formalin-fixed VX2 rabbit cancer specimen with 15-mm in diameter. The PCCT system consisted of an asymmetrically cut silicon (220) crystal, a monolithic x-ray interferometer, a phase-shifter, an object cell and an x-ray CCD camera. The PCCT at 35 keV clearly visualized various inner structures of VX2 rabbit cancer such as necrosis, cancer, the surrounding tumor vessels, and normal liver tissue. Besides, image-contrast was not degraded significantly. These results suggest that the PCCT at 35 KeV is sufficient to clearly depict the histopathological morphology of VX2 rabbit cancer specimen.

  4. The Context for IMAP: Voyager and INCA Observations of the Heliosheath at E > 5 keV

    Science.gov (United States)

    Krimigis, Stamatios M.

    2016-04-01

    The basic premise of the proposed Interstellar Mapping and Acceleration Probe (IMAP) is detailed scientific understanding of the Heliosheath (HS) and beyond, a region of space explored in situ by Voyager 1 (V1) since 2004, Voyager 2 (V2) since 2007, and remotely via energetic neutral atoms (ENA) by the Cassini/INCA (Ion and Neutral CAmera) since 2003 and IBEX since 2009. The IMAP instrumentation proposed for this purpose combines and extends the IBEX and INCA ENA energy ranges (0.3- 20 keV and 3-200 keV, for low and high energy, respectively). All three missions-Voyagers, Cassini/INCA, and IBEX- have made discovery-class measurements in the HS, the Voyagers providing in situ ion intensities at E > 30 keV, while INCA images ENA in the range 5 INCA ENA allows for the possibility of observing the intensity and time evolution of ions in the HS, thought to give rise to the ENAs via charge-exchange, and the resultant ENA images in the inner heliosphere and their spatial and/or temporal variability. Unfortunately, no such "ground truth" ion measurements are possible at Voyager in the ENA energy range imaged by IBEX. Some of the key findings from the Voyager and Cassini/INCA measurements are as follows: (1) The HS contains a hot plasma population that carries a substantial part (30-50 %) of the total pressure at E > 5 keV, the rest residing below that range, resulting in a beta (particle/magnetic pressure) always > 1, typically >10. (2) The width of the HS in the direction of V1 is ~ 30 AU, but is thought to be larger (40-70 AU) in the southern ecliptic where V2 currently travels.. (3) The ENA intensities at E > 5 keV exhibit a correlation with the solar cycle (SC) over the period 2003 to 2015, with minimum intensities in the anti-nose direction observed ~ 1.5 yrs after solar minimum followed by a recovery thereafter. (4) The in situ ion measurements at V2 within the HS also show a similar SC dependence. The totality of the observations, together with the near

  5. Studies towards the understanding of the effects of ionizing radiations at the molecular scale (20-150 keV H{sup +}/H + He Collisions; dissociative electron attachment to water)

    Energy Technology Data Exchange (ETDEWEB)

    Coupier, B

    2005-11-15

    This work comes within the scope of recent studies towards a better understanding of the effect of ionizing radiation at the molecular scale on biological systems. It is composed of two parts. The first one presents a new set of coincidence measurements of cross sections for the impact of protons or hydrogen atoms on helium in the energy range 20-150 keV of interest for the radiation biology. It is an archetypical system of interest for the theoreticians and there exists only a few studies on the impact of hydrogen atoms on helium. This study with helium was also motivated for the sake of performing a general test of functioning of the apparatus before investigating more complicated systems. Similar studies were then performed by replacing helium with water and biological molecules of relevance (Uracil, Thymine...) as target. This constitutes a study of direct effects of fast ionizing radiations on molecules of biological interest. The second part of the thesis deals with another type of ionizing radiations which can be seen as indirect effects of the first fast ionizing radiations studied in the first part. Low energy electrons emission in the energy range 1 to 16 eV follows the bombardment of the matter by swift protons/hydrogen atoms; these electrons have in turn an ionizing influence on the environment. A review of the dissociative electron attachment to water was undertaken motivated by the existing discrepancies between old studies on the same subject. A special attention was given to the problem of high energy kinetic ion discrimination in the trochoidal monochromator used for this work. (author)

  6. 20-300)kVX射线参考辐射装置的建立%The Establishment of Reference Radiation Device in the range of (20-300) kV X-rays

    Institute of Scientific and Technical Information of China (English)

    葛双; 吴金杰; 郭彬; 王培玮; 杨扬; 邱小平

    2016-01-01

    为了推进X射线空气比释动能基准量值传递工作的开展,建立了(20-300) kV X射线参考辐射装置。距离X光管焦点1 m的均匀野处,建立了CCRI会议推荐的两组低能X射线参考辐射质50 kV( a)和50 kV( b),采用拟合方法测量得到的半值层、同质系数与推荐值相差2%以内。通过蒙卡模拟软件EGSnrc研究两组参考辐射质的能谱分布情况,并计算了其平均能量,分别为33.3和28.1 keV。%For promoting the work that the air -kerma primary standard value be transferred , the reference radi-ation device is established in the range of (20-300 ) kV X-rays.Two low-energy reference radiation quali-ties 50 kV ( a) and 50 kV ( b) recommend by CCRI are established on the uniform radiation field .The distance from the source to the reference plane is 1 m.Half-value layer and homogeneity coefficient are measured by the fitting method .The difference with the recommended values is within 2%.Their spectrum distribution can be got by Monte Carlo simulation software EGSnrc and their average energies are calculated to be 33.3 keV and 28 .1 keV respectively .

  7. An Examination of Directional Discontinuities and Magnetic Polarity Changes around Interplanetary Sector Boundaries Using E > 2 keV Electrons

    Science.gov (United States)

    Kahler, S. W.; Lin, R. P.

    1995-10-01

    Past studies of interplanetary magnetic sector boundaries have been based on the assumption that one can determine the field polarities by comparing the field directions with those of the nominal Parker spiral angles. Previous investigators have found evidence for decreases of ∣B∣, the magnitude of the magnetic fieldB, and increases of Θ, the angle betweenB and the ecliptic plane, at sector boundaries. Others have argued that the characteristic thickness of sector boundaries exceeds that of tangential discontinuities, making sector boundaries a separate class of structures. We use a simple technique for inferring the polarities of interplanetary magnetic fields based on the assumption thatE > 2 keV electrons are always flowing along the magnetic field away from the Sun. Electron data from the UC Berkeley experiment on the ISEE-3 spacecraft are used to examine periods around several apparent sector boundaries in 1978 and 1979. We compare properties of (a) boundaries with field polarity changes and (b) large-angle (ω > 60°) directional discontinuities with no field polarity changes. We find no significant differences between the sector boundaries and the directional discontinuities in terms of associated decreases in ∣B∣ or of values of Θ. These results suggest no significant difference between sector boundaries and directional discontinuities other than the change in field polarities. Within limited statistics we find that about half the polarity changes would not have been identified using a requirement thatω > 90° and that half of theω > 120° discontinuities would have been misidentified as polarity changes.

  8. Inferring Compton-thick AGN candidates at z > 2 with Chandra using the >8 keV rest-frame spectral curvature

    Science.gov (United States)

    Baronchelli, L.; Koss, M.; Schawinski, K.; Cardamone, C.; Civano, F.; Comastri, A.; Elvis, M.; Lanzuisi, G.; Marchesi, S.; Ricci, C.; Salvato, M.; Trakhtenbrot, B.; Treister, E.

    2017-10-01

    To fully understand cosmic black hole growth, we need to constrain the population of heavily obscured active galactic nuclei (AGNs) at the peak of cosmic black hole growth (z ∼1-3). Sources with obscuring column densities higher than 1024 atoms cm-2, called Compton-thick (CT) AGNs, can be identified by excess X-ray emission at ∼20-30 keV, called the 'Compton hump'. We apply the recently developed Spectral Curvature (SC) method to high-redshift AGNs (2 detected with Chandra. This method parametrizes the characteristic 'Compton hump' feature cosmologically redshifted into the X-ray band at observed energies 5 × 1043erg s-1. In the Cosmological Evolution Survey (COSMOS), we find an observed CT fraction of 15^{+4}_{-3} per cent (40/272) or 32 ± 11 per cent when corrected for the survey sensitivity. When comparing to low redshift AGNs with similar X-ray luminosities, our results imply that the CT AGN fraction is consistent with having no redshift evolution. Finally, we provide SC equations that can be used to find high-redshift CT AGNs (z > 1) for current (XMM-Newton) and future (eROSITA and ATHENA) X-ray missions.

  9. Personal dose equivalent conversion coefficients for neutron fluence over the energy range of 20 to 250 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Mclean, Thomas D [Los Alamos National Laboratory; Justus, Alan L [Los Alamos National Laboratory; Gadd, S Milan [Los Alamos National Laboratory; Olsher, Richard H [RP-2; Devine, Robert T [RP-2

    2009-01-01

    Monte Carlo simulations were performed to extend existing neutron personal dose equivalent fluence-to-dose conversion coefficients to an energy of 250 MeV. Presently, conversion coefficients, H(p,slab)(10,alpha)/Phi, are given by ICRP-74 and ICRU-57 for a range of angles of radiation incidence (alpha = 0, 15, 30, 45, 60 and 75 degrees ) in the energy range from thermal to 20 MeV. Standard practice has been to base operational dose quantity calculations <20 MeV on the kerma approximation, which assumes that charged particle secondaries are locally deposited, or at least that charged particle equilibrium exists within the tally cell volume. However, with increasing neutron energy the kerma approximation may no longer be valid for some energetic secondaries such as protons. The Los Alamos Monte Carlo radiation transport code MCNPX was used for all absorbed dose calculations. Transport models and collision-based energy deposition tallies were used for neutron energies >20 MeV. Both light and heavy ions (HIs) (carbon, nitrogen and oxygen recoil nuclei) were transported down to a lower energy limit (1 keV for light ions and 5 MeV for HIs). Track energy below the limit was assumed to be locally deposited. For neutron tracks <20 MeV, kerma factors were used to obtain absorbed dose. Results are presented for a discrete set of angles of incidence on an ICRU tissue slab phantom.

  10. INTEGRAL Observations of SGR1806-20

    Science.gov (United States)

    Hurley, K.; Mazets, E.; Golenetskii, S.; Frederiks, D.; Atteia, J. L.; Boer, M.; Brandt, S.; Lund, N.; Pedersen, H.; Cline, T.; Ibrahim, A.; Costa, E.; Feroci, M.; Ubertini, P.; Del Santo, M.; Frontera, F.; Pizzichini, G.; Castro-Tirado, A.; Gimenez, A.; Winkler, C.; Schoenfelder, V.; von Kienlin, A.; Lichti, G.; Sunyaev, R.; Kretschmar, P.; Produit, N.; Mereghetti, S.; Goetz, D.; Mirabel, F.; Woods, P.; Kouveliotou; Finger, M.; Gogus, E.; Thompson, C.; Duncan, R.; Pavlov, G.; van der Klis, M.; Molkov, S.

    2004-12-01

    INTEGRAL has observed the soft gamma repeater SGR1806-20 for over 2.2 million seconds in the course of two target of opportunity observations and two Galactic center deep exposures in the AO-1 and AO-2 periods. In these observations, the quiescent emission was detected and its spectrum measured to over 100 keV for the first time by IBIS. More than 100 bursts were detected by IBIS in the 15-200 keV energy range, and more than 30 of them were also detected by JEM-X in the 3-35 keV energy range. We discuss the fluence distribution of SGR1806 bursts, and their spectral evolution. We also set an upper limit to the quiescent flux from the SGR-like source discovered by HETE, SGR1808-20. This work was supported by the INTEGRAL U.S. Guest Investigator program under NASA grant NAG5-13738.

  11. The temperature effect on the glycine decomposition induced by 2 keV electron bombardment in space analog conditions

    Science.gov (United States)

    Pilling, Sergio; Nair, Binu G.; Escobar, Antonio; Fraser, Helen; Mason, Nigel

    2014-03-01

    Glycine is the simplest proteinaceous amino acid that has been extensively detected in carbonaceous meteorites and was recently observed in the cometary samples returned to Earth by NASA's Stardust spacecraft. In space, such species is exposed to several radiation fields at different temperatures. In aqueous solutions, this species appears mainly as zwitterionic glycine (+NH3CH2COO-) however, in solid phase, it may be found in amorphous or crystalline forms. Here, we present an experimental study on the destruction of two zwitterionic glycine crystals ( α- and β-form) at two different temperatures (300 K and 14 K) by 2 keV electrons in an attempt to test the behavior and stability of this molecular species in different space environments. The samples were analyzed in situ by Fourier transform infrared spectrometry at electron fluences. The experiments were carried out under ultra-high vacuum conditions at the Molecular Physics Laboratory at the Open University at Milton Keynes, UK. The dissociation cross section of glycine is approximately 5 times higher for the 14 K samples when compared to the 300 K samples. In contrast, no significant differences emerged between the dissociation cross sections of α- and β-forms of glycine for fixed temperature experiments. We therefore conclude that the destruction cross section is more heavily dependent on temperature than the phase of the condensed glycine material. This may be associated with the opening of additional reaction routes in the frozen samples involving the trapped daughter species (e.g. CO2 and CO). The half-life of studied samples extrapolated to space conditions shows that glycine molecules on the surface of interstellar grains has less survivability and they are highly sensitive to ambient radiations, however, they can survive extended period of time in the solar system like environments. Survivability increases by a factor of 5 if the samples are at 300 K when compared to low temperature experiments at 14

  12. The 2-10 keV unabsorbed luminosity function of AGN from the LSS, CDFS, and COSMOS surveys

    Science.gov (United States)

    Ranalli, P.; Koulouridis, E.; Georgantopoulos, I.; Fotopoulou, S.; Hsu, L.-T.; Salvato, M.; Comastri, A.; Pierre, M.; Cappelluti, N.; Carrera, F. J.; Chiappetti, L.; Clerc, N.; Gilli, R.; Iwasawa, K.; Pacaud, F.; Paltani, S.; Plionis, E.; Vignali, C.

    2016-05-01

    The XMM-Large scale structure (XMM-LSS), XMM-Cosmological evolution survey (XMM-COSMOS), and XMM-Chandra deep field south (XMM-CDFS) surveys are complementary in terms of sky coverage and depth. Together, they form a clean sample with the least possible variance in instrument effective areas and point spread function. Therefore this is one of the best samples available to determine the 2-10 keV luminosity function of active galactic nuclei (AGN) and their evolution. The samples and the relevant corrections for incompleteness are described. A total of 2887 AGN is used to build the LF in the luminosity interval 1042-1046 erg s-1 and in the redshift interval 0.001-4. A new method to correct for absorption by considering the probability distribution for the column density conditioned on the hardness ratio is presented. The binned luminosity function and its evolution is determined with a variant of the Page-Carrera method, which is improved to include corrections for absorption and to account for the full probability distribution of photometric redshifts. Parametric models, namely a double power law with luminosity and density evolution (LADE) or luminosity-dependent density evolution (LDDE), are explored using Bayesian inference. We introduce the Watanabe-Akaike information criterion (WAIC) to compare the models and estimate their predictive power. Our data are best described by the LADE model, as hinted by the WAIC indicator. We also explore the recently proposed 15-parameter extended LDDE model and find that this extension is not supported by our data. The strength of our method is that it provides unabsorbed, non-parametric estimates, credible intervals for luminosity function parameters, and a model choice based on predictive power for future data. Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA member states and NASA.Tables with the samples of the posterior probability distributions

  13. Response times of Cassini/INCA > 5.2 keV ENAs and Voyager ions in the heliosheath over the solar cycle

    Science.gov (United States)

    Dialynas, K.; Krimigis, S. M.; Mitchell, D. G.; Decker, R. B.; Roelof, E. C.

    2017-09-01

    Both a magnetosphere-like tail and a bubble model of the heliosphere were posited by E. N. Parker in 1961. Recently, we showed that heliosheath ions are the source of > 5.2 keV Energetic Neutral Atoms (ENA), whose images of the heliosphere exhibit a rough nose to anti-nose (tail) global symmetry that resembles a diamagnetic bubble. The comparison between energetic neutral atom (ENA) global images of the helioshphere obtained with the Ion and Neutral Camera (INCA) on board Cassini and ions measured in-situ by the Low Energy Charged Particle experiment (LECP) on board Voyager 1 and 2 (V1/V2) in overlapping energy bands over an 11-year period shows that the heliosphere responds promptly, within ∼2-3 years, to outward propagating solar wind changes in both the nose and tail directions. Here we focus on the recovery of solar cycle 24 and the response times of > 5.2 keV ENAs to show that this ∼2-3-year time delay is consistent with a “tail” of ∼80-120 AU. This preliminary rough calculation is generally consistent with lower energy ENA data (E < 6 keV, from the IBEX-Lo and IBEX-Hi) and is supported by recent modelling of the heliosphere.

  14. Introducing Science 2.0!

    Science.gov (United States)

    Brunsell, Eric; Horejsi, Martin

    2010-01-01

    The internet of the mid-to-late 1990s was defined by static web pages created by people with specialized technical skills. Today, that barrier has been all but eliminated with the emergence of easy-to-use online tools for creating and sharing content. "Web 2.0," or the read/write web, has dramatically altered the way we communicate and share…

  15. Learning UML 2.0

    CERN Document Server

    Miles, Russ

    2006-01-01

    Engaging and accessible, this book shows you how to use UML to craft and communicate your project's design. Russ Miles and Kim Hamilton have written a pragmatic introduction to UML based on hard-earned practice, not theory. Regardless of the software process or methodology you use, this book is the one source you need to get up and running with UML 2.0

  16. Sputtering of solid neon by keV hydrogen ions

    DEFF Research Database (Denmark)

    Ellegaard, Ole; Schou, Jørgen; Sørensen, H.

    1986-01-01

    Sputtering of solid Ne with the hydrogen ions H+1, H+2 and H+3 in the energy range 1–10 keV/atom has been studied by means of a quartz microbalance technique. No enhancement in the yield per atom for molecular ions was found. The results for hydrogen ions are compared with data for keV electrons....

  17. Scaling of C{sub 60} ionization and fragmentation with the energy deposited in collisions with H{sup +}, H{sub 2}{sup +}, H{sub 3}{sup +} and He{sup +} ions (2-130 keV)

    Energy Technology Data Exchange (ETDEWEB)

    Bordenave-Montesquieu, D. [LCAR, IRSAMC, UMR 5589 CNRS, Universite Paul Sabatier, Toulouse (France)]. E-mail: dbm@yosemite.ups-tlse.fr; Moretto-Capelle, P.; Bordenave-Montesquieu, A.; Rentenier, A. [LCAR, IRSAMC, UMR 5589 CNRS, Universite Paul Sabatier, Toulouse (France)

    2001-03-14

    Fragmentation, ionization and C{sub 2} fragment evaporation of the C{sub 60} molecule induced by collisions with H{sup +}, H{sub 2}{sup +}, H{sub 3}{sup +} and He{sup +} monocharged ions have been measured in coincidence with the electron emission in the 2-130 keV projectile energy range. The time-of-flight mass spectra were found to vary strongly with the collision energy or velocity and the projectile. On the other hand, they scale rather nicely with the energy deposited in the molecule. Relative weights of the total multi-fragmentation into small C{sub n}{sup +} fragments (n=1-14), individual multi-fragmentation (n=1,7 and 11), double ionization of the intact molecule and evaporation of C{sub 2} molecules associated with the doubly charged fullerene ion, are used to illustrate our finding quantitatively. (author). Letter-to-the-editor.

  18. Stopping power for electrons in pyrimidine in the energy range 20-3000 eV.

    Science.gov (United States)

    Colmenares, R; Sanz, A G; Fuss, M C; Blanco, F; García, G

    2014-01-01

    In this work, we present new experimental electron energy loss distribution functions for pyrimidine (C4H4N2) measured for the incident energy range 30-2000 eV. Theoretical total and elastic cross sections for electron scattering from pyrimidine were calculated using the screening-corrected additivity rule (IAM-SCAR) method. Based on the mean energy loss observed in the experiment and the theoretical integral inelastic cross section, the stopping power for electrons in pyrimidine is calculated in the energy range 20-3000 eV.

  19. Neutron fluence and energy reconstruction with the IRSN recoil detector μ-TPC at 27 keV, 144 keV and 565 keV

    Energy Technology Data Exchange (ETDEWEB)

    Maire, D.; Lebreton, L.; Richer, J.P. [IRSN, PRP-HOM, SDE, LMDN, 13115 Saint Paul-Lez-Durance (France); Bosson, G.; Bourrion, O.; Guillaudin, O.; Riffard, Q.; Santos, D. [CNRS/IN2P3-UJF-INPG, LPSC, 38000 Grenoble (France)

    2015-07-01

    The French Institute for Radioprotection and Nuclear Safety (IRSN), associated to the French Metrology Institute (LNE), is developing a time projection chamber using a Micromegas anode: μ-TPC. This work is carried out in collaboration with the Laboratory of Subatomic Physics and Cosmology (LPSC). The aim is to characterize with a primary procedure the energy distribution of neutron fluence in the energy range 8 keV - 1 MeV. The time projection chambers are gaseous detectors, which are able to measure charged particles energy and to reconstruct their track if a pixelated anode is used. In our case, the gas is used as a (n, p) converter in order to detect neutrons down to few keV. Coming from elastic collisions with neutrons, recoil protons lose a part of their kinetic energy by ionizing the gas. The ionization electrons are drifted toward a pixelated anode (2D projection), read at 50 MHz by a self-triggered electronic system to obtain the third track dimension. The neutron energy is reconstructed event by event thanks to proton scattering angle and proton energy measurements. The scattering angle is deduced from the 3D track. The proton energy is obtained by charge collection measurements, knowing the ionization quenching factor (i.e. the part of proton kinetic energy lost by ionizing the gas). The fluence is calculated thanks to the detected events number and the simulated detector response. The μ-TPC is a new reliable detector which enables to measure energy distribution of the neutron fluence without deconvolution or neutron calibration contrary to usual gaseous counters. The μ-TPC is still being developed and measurements have been carried out at the AMANDE facility, with neutrons energies going from 8 keV to 565 keV. After the context and the μ-TPC working principle presentation, measurements of the neutron energy and fluence at 27.2 keV, 144 keV and 565 keV are shown and compared to the complete detector simulation. This work shows the first direct

  20. Spectral and temporal properties of long GRBs detected by INTEGRAL from 3 keV to 8 MeV

    DEFF Research Database (Denmark)

    Martin-Carrillo, A.; Topinka, M.; Hanlon, L.;

    2010-01-01

    Since its launch in 2002, INTEGRAL has triggered onmore than 78 g –ray bursts in the 20-200 keV energy range with the IBIS/ISGRI instrument. Almost 30% of these bursts occurred within the fully coded field of view of the JEM-X detector (5) which operates in the 3-35 keV energy range. A detailed...

  1. Intranet 2.0: Fostering Collaboration

    OpenAIRE

    Engard, Nicole C.; Park, Rayana Min

    2006-01-01

    This article discusses the development of the Jenkins Law Library Intranet 2.0. The updated intranet consists of a wide range of warm colors and 3-D images for depth and an inviting look. Task-related tabs, which are the main navigation system for the intranet, are used to move away from organizing data based on departments and toward fostering collaboration among all areas of the library. Also, symbols remain constant throughout the site, making the correlation between illustration and funct...

  2. Mass attenuation coefficient of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using 16.59 – 25.26 keV photon energy range

    Energy Technology Data Exchange (ETDEWEB)

    Mohd Yusof, Mohd Fahmi, E-mail: mfahmi@usm.my; Hamid, Puteri Nor Khatijah Abdul; Tajuddin, Abdul Aziz [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Bauk, Sabar [School of Distance Education, Universiti Sains Malaysia, 11800 Penang (Malaysia); Hashim, Rokiah [School of Industrial Technologies, Universiti Sains Malaysia, 11800 Penang (Malaysia)

    2015-04-29

    The Rhizophora spp. particleboards were fabricated using ≤ 104 µm particle size at three different fabrication methods; binderless, steam pre-treated and tannin-added. The mass attenuation coefficient of Rhizophora spp. particleboards were measured using x-ray fluorescent (XRF) photon from niobium, molybdenum, palladium, silver and tin metal plates that provided photon energy between 16.59 to 25.26 keV. The results were compared to theoretical values for water calculated using photon cross-section database (XCOM).The results showed that all Rhizophora spp. particleboards having mass attenuation coefficient close to calculated XCOM for water. Tannin-added Rizophora spp. particleboard was nearest to calculated XCOM for water with χ2 value of 13.008 followed by binderless Rizophora spp. (25.859) and pre-treated Rizophora spp. (91.941)

  3. Introducing ADS 2.0

    Science.gov (United States)

    Accomazzi, Alberto; Kurtz, M. J.; Henneken, E. A.; Grant, C. S.; Thompson, D.; Luker, J.; Chyla, R.; Murray, S. S.

    2014-01-01

    In the spring of 1993, the Smithsonian/NASA Astrophysics Data System (ADS) first launched its bibliographic search system. It was known then as the ADS Abstract Service, a component of the larger Astrophysics Data System effort which had developed an interoperable data system now seen as a precursor of the Virtual Observatory. As a result of the massive technological and sociological changes in the field of scholarly communication, the ADS is now completing the most ambitious technological upgrade in its twenty-year history. Code-named ADS 2.0, the new system features: an IT platform built on web and digital library standards; a new, extensible, industrial strength search engine; a public API with various access control capabilities; a set of applications supporting search, export, visualization, analysis; a collaborative, open source development model; and enhanced indexing of content which includes the full-text of astronomy and physics publications. The changes in the ADS platform affect all aspects of the system and its operations, including: the process through which data and metadata are harvested, curated and indexed; the interface and paradigm used for searching the database; and the follow-up analysis capabilities available to the users. This poster describes the choices behind the technical overhaul of the system, the technology stack used, and the opportunities which the upgrade is providing us with, namely gains in productivity and enhancements in our system capabilities.

  4. WMS Server 2.0

    Science.gov (United States)

    Plesea, Lucian; Wood, James F.

    2012-01-01

    This software is a simple, yet flexible server of raster map products, compliant with the Open Geospatial Consortium (OGC) Web Map Service (WMS) 1.1.1 protocol. The server is a full implementation of the OGC WMS 1.1.1 as a fastCGI client and using Geospatial Data Abstraction Library (GDAL) for data access. The server can operate in a proxy mode, where all or part of the WMS requests are done on a back server. The server has explicit support for a colocated tiled WMS, including rapid response of black (no-data) requests. It generates JPEG and PNG images, including 16-bit PNG. The GDAL back-end support allows great flexibility on the data access. The server is a port to a Linux/GDAL platform from the original IRIX/IL platform. It is simpler to configure and use, and depending on the storage format used, it has better performance than other available implementations. The WMS server 2.0 is a high-performance WMS implementation due to the fastCGI architecture. The use of GDAL data back end allows for great flexibility. The configuration is relatively simple, based on a single XML file. It provides scaling and cropping, as well as blending of multiple layers based on layer transparency.

  5. Relative dissociation fractions of N2O under 15 -30 -keV H-,C- , and O- negative-ion impact

    Science.gov (United States)

    Wang, Dedong; Guo, Guannan; Min, Guangxin; Zhang, Xuemei

    2017-01-01

    The relative dissociation fractions of N2O are studied under 15-30-keV negative ions H-,C- , and O- impact. The recoil ions and ion pairs originating from the target molecule N2O are detected and identified in coincidence with scattered ions in single electron loss (SL) and double electron loss (DL) channels using a time-of-flight mass spectrometer. The dissociation fractions for the production of the fragment ions are obtained. We find that the relative dissociation fractions in SL are smaller than those in DL, and the degree of fragmentation will become greater with the impact energy increasing. We also analyze the coincident TOF spectra of two fragment ions which are produced from dissociation of N2O2 + and give the possible dissociation pathways of N2O2 + with 15 -30 -keV H-,C- , and O- impact. There are many studies on N2O with positive-ion, photon, and electron impact, and we compare our results under negative-ion impact with those works.

  6. Discussing the physical meaning of the absorption feature at 2.1 keV in 4U 1538-52

    OpenAIRE

    Rodes Roca, José Joaquín; Torrejon, Jose M.; Martínez Núñez, Silvia; Giménez García, Ángel; Bernabeu, Guillermo

    2014-01-01

    High resolution X-ray spectroscopy is a powerful tool for studying the nature of the matter surrounding the neutron star in X-ray binaries and its interaction between the stellar wind and the compact object. In particular, absorption features in their spectra could reveal the presence of atmospheres of the neutron star or their magnetic field strength. Here we present an investigation of the absorption feature at 2.1 keV in the X-ray spectrum of the high mass X-ray binary 4U 1538–52 based on ...

  7. High negative ion production yield in 30 keV F{sup 2+} + adenine (C{sub 5}H{sub 5}N{sub 5}) collisions

    Energy Technology Data Exchange (ETDEWEB)

    Li, B; Ma, X; Zhu, X L; Zhang, S F; Liu, H P; Feng, W T; Qian, D B; Zhang, D C [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Chen, L; Bredy, R; Montagne, G; Bernard, J; Martin, S [Universite de Lyon, F-69622, Lyon (France) and Universite Lyon 1, Villeurbanne; CNRS, UMR5579, LASIM (France)], E-mail: chen@univ-lyon1.fr

    2009-04-14

    In collisions between slow F{sup 2+} ions (30 keV) and molecular targets, adenine, scattered particle production yields have been measured directly by simultaneous detection of neutrals, positive and negative ions. The relative cross-section for a negative ion formation channel was measured to be 1%. Despite a slight decrease compared to a larger target, the fullerene C{sub 60}, the measured negative ion formation cross section is still at least one order of magnitude larger than the yield in ion-atom interactions.

  8. Electric properties of biodiesel in the range from 20 Hz to 20 MHz. Comparison with diesel fossil fuel

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Prieto, L.E. [Grupo de Energias Renovables, Facultad de Ingenieria, Universidad de Buenos Aires, Av. Paseo Colon 850, Buenos Aires, 1063 (Argentina); Sorichetti, P.A. [Laboratorio de Sistemas Liquidos, Facultad de Ingenieria, Universidad de Buenos Aires, Buenos Aires (Argentina); Romano, S.D. [Grupo de Energias Renovables, Facultad de Ingenieria, Universidad de Buenos Aires, Av. Paseo Colon 850, Buenos Aires, 1063 (Argentina); CONICET: Consejo Nacional de Investigaciones Cientificas y Tecnicas, Av. Rivadavia 1917, Buenos Aires, 1033 (Argentina)

    2008-07-15

    Determination of electric properties at the different steps of biodiesel (BD) production contributes to a better understanding of the influence of the variables. Measurements of complex permittivity and conductivity make possible to survey efficiently the diverse steps of the industrial-scale production process, from the conditioning of the raw material to the quality control of the final product. Moreover, electrical measurements are 'non-destructive' and require relatively small sample volumes. In this work, complex permittivity spectra of BD and DF from 20 Hz to 20 MHz are presented. Experimental data were taken in a range of temperatures from 25 to 75 C, measured with an accuracy of {+-}0.1 C. The measuring system used in this work requires a sample volume of 25cm{sup 3} and gives the real part of permittivity ({epsilon}{sup '}) with an accuracy better than 1%. Dielectric loss (tg{delta}) can be measured between 10{sup -2} and 10{sup 2}. (author)

  9. Performance of a Supersonic Ramp-type Side Inlet with Ram-scoop Throat Bleed and Varying Fuselage Boundary-layer Removal : Mach Number Range 1.5 to 2.0 / Glenn A. Mitchell and Robert C. Campbell

    Science.gov (United States)

    Mitchell, Glenn A; Campbell, Robert C

    1957-01-01

    Provided sufficient throat bleed was employed, maximum pressure recoveries of 0.87 to 0.88 at Mach number 2.0 were obtained for a fuselage-mounted 14 degrees ramp inlet regardless of the amount of fuselage boundary layer ingested. The addition of inlet side fairings yielded further increases in pressure recovery to 0.90 to 0.91, decreased critical drag coefficients, and increased critical mass-flow ratios. With throat bleed, peak pressure recoveries and calculated thrust-minus-drag values were comparable at two axial positions of the scoop and were highest with the greatest amount of fuselage boundary layer ingested.

  10. Dynamical study of sup 1 H(d,gamma) sup 3 He tensor observables in the energy range of 80 kev to 95 MeV tests of effective two-body models

    CERN Document Server

    Fonseca, A C

    2000-01-01

    Realistic interactions are used to study sup 1 H(d, gamma) sup 3 He tensor observables in the energy range of 80 keV to 95 MeV deuteron laboratory energy, as well as the differential cross section for the two-body photodisintegration of sup 3 He. The Siegert form of the E1 multipole operator in the long-wavelength limit is taken as the sole component of the electromagnetic interaction. The three-body Faddeev equations for the bound-state and continuum wave functions are solved using the Paris, Argonne V14, Bonn-A, and Bonn-B potentials. The corresponding nucleon-nucleon t-matrices are represented in a separable form using the Ernst-Shakin-Thaler representation. The Coulomb force between protons is neglected and no three-nucleon force is included. The contribution of nucleon-nucleon P-wave components to the observables is carefully studied, not only in the angular distribution of the observables, but also as a function of the deuteron laboratory energy for fixed centre-of-mass angle. Comparison with data is sh...

  11. Interaction between Solid Nitrogen and 1-3-keV Electrons

    DEFF Research Database (Denmark)

    Schou, Jørgen; Sørensen, H.

    1978-01-01

    Experimental studies were made of the interaction between solid nitrogen and beams of 1-2-keV electrons. The projected range for the electrons was measured by means of the mirror-substrate method (gold substrate), giving the result 9.02×1016 E1.75 molecules/cm2 with the energy given in ke......V. The escape depth for secondary electrons was studied by means of the equivalent-substrate method (carbon substrate). The results varied from 280 Å at 1 keV to 400 Å at 3 keV. Measurements were also made of the secondary-electron-emission coefficient, which varied from 2.3 el/el at 1 keV to 1.2 el/el at 3 ke......V. At 3 keV, the SEE coefficient is 12 times that for solid deuterium. This is attributed partly to the larger production rate for low-energy electrons in nitrogen and partly to the larger escape probability for these electrons. Moreover, measurements were made of the electron-reflection coefficient, both...

  12. DC CONDUCTIVITY OF CERAMICS WITH CALCITE WASTE IN THE TEMPERATURE RANGE 20 - 1050C

    Directory of Open Access Journals (Sweden)

    Jan Ondruska

    2015-06-01

    Full Text Available The temperature dependences of the electrical DC conductivity of calcite waste, kaolinite and illite based ceramics were measured in the temperature range of 20 - 1050oC. The ceramic mass that was used was a mixture of 60 wt. % kaolinitic-illitic clay, 20 - 40 wt. % of this clay was fired at 1000oC for 90 min and 0, 10 and 20 wt. % of calcite waste. During heating, several processes take place - the release of the physically bound water, the burning of organic impurities, the dehydroxylation of kaolinite and illite, the decomposition of calcite, and the creation of anorthite and mullite. All of these processes were checked by means of differential thermal analysis (DTA, derivative thermogravimetry (DTG and thermodilatometry (TDA. At low temperatures (20 - 200oC, due to the release and decomposition of physically bound water, H+ and OH- are dominant charge carriers. After completion of release of physically bound water, up to the start of dehydroxylation at the temperature of ~ 450oC, the DC conductivity is dominated by a transport of Na+, K+, and Ca2+ ions. During dehydroxylation, H+ and OH- ions, which are released from kaolinite and illite lattices, contribute to the DC conductivity. Decomposition of calcite runs between ~ 700oC and 900oC. The glassy phase has a dominant influence on the DC conductivity in the fired ceramics. Its high conductivity is determined by the high mobility of Na+, K+, and Ca2+ ions.

  13. Radiation-induced luminescence from TiO{sub 2} by 10 keV O{sup +}, N{sup +} and Ar{sup +} ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kitazawa, Sin-iti, E-mail: kitazawa.siniti@jaea.go.j [Naka Fusion Institute, Japan Atomic Energy Agency (JAEA), 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Nuclear Science Research Institute, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan); Saitoh, Yuichi; Yamamoto, Shunya; Asano, Masaharu [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Ishiyama, Shintaro [Nuclear Science Research Institute, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan)

    2009-05-01

    Radiation-induced luminescence (RIL) produced by 10 keV O{sup +}, N{sup +} and Ar{sup +} irradiation at room temperature has been used to study energy transfer in titanium dioxide (TiO{sub 2}) targets. RIL spectra in the UV-visible region show numerous atomic lines and three bands. Two visible bands by crystalline defects and an UV band at 3.9 eV originating from radiation transitions between the Ti{sup 3+} 3d and O{sup 2-} 2 s states in the TiO{sub 2} crystal are observed. The experimental results suggest that the excitations were not mainly produced by transitions from the ground state to excited states but by cascade radiations from higher excited states.

  14. Thermal Stability of Austempered Ductile Iron Evaluated in a Temperature Range of 20-300K

    Directory of Open Access Journals (Sweden)

    Dawid MYSZKA

    2016-05-01

    Full Text Available The aim of this article was to determine through changes in magnetic properties the stability of the austempered ductile iron (ADI microstructure during temperature changes in a range of 20 – 300 K. The measurements were taken in a vibrating sample magnetometer (VSM using Fe27Ni2TiMoAlNb austenitic stainless steel and four types of austempered ductile iron obtained under various heat treatment conditions. The plotted curves showing changes in the magnetisation degree as a function of temperature had a number of characteristic points illustrating changes taking place in the microstructure. For each of the materials examined, the martensite start temperature Ms and the temperature range within which the martensitic transformation takes place were identified.

  15. Thermal Stability of Austempered Ductile Iron Evaluated in a Temperature Range of 20-300K

    Directory of Open Access Journals (Sweden)

    Dawid MYSZKA

    2016-05-01

    Full Text Available The aim of this article was to determine through changes in magnetic properties the stability of the austempered ductile iron (ADI microstructure during temperature changes in a range of 20 – 300 K. The measurements were taken in a vibrating sample magnetometer (VSM using Fe27Ni2TiMoAlNb austenitic stainless steel and four types of austempered ductile iron obtained under various heat treatment conditions. The plotted curves showing changes in the magnetisation degree as a function of temperature had a number of characteristic points illustrating changes taking place in the microstructure. For each of the materials examined, the martensite start temperature Ms and the temperature range within which the martensitic transformation takes place were identified.

  16. Colliding the hydrocarbon building blocks of astrochemical polycyclic aromatic hydrocarbons with 8 keV He+* and H2+* ions: Luminescence from methane, acetylene, benzene and naphthalene

    Science.gov (United States)

    Rashid, Shaan; Sit, Alicia; West, Brandi; Mayer, Paul M.

    2017-01-01

    Emission spectra from collisions of 8 keV He+* and H2+* with neutral naphthalene, benzene, acetylene and methane were acquired over 190-1020 nm on a modified double-focusing mass spectrometer. The bands, emission intensities and the minimum excitation energy to produce the observed transitions (Emin) were compared for the two projectile ions. Emin values were the same for both projectiles but the emission intensity is greater in the case of He+*. This is consistent with calculations at the CISD/6-311+G(2df) level on the excited states of the respective collision complexes which exhibited two distinct state-crossing points for He+* collisions but none for H2+* collisions.

  17. Web 2.0 Applications in China

    Science.gov (United States)

    Zhai, Dongsheng; Liu, Chen

    Since 2005, the term Web 2.0 has gradually become a hot topic on the Internet. Web 2.0 lets users create web contents as distinct from webmasters or web coders. Web 2.0 has come to our work, our life and even has become an indispensable part of our web-life. Its applications have already been widespread in many fields on the Internet. So far, China has about 137 million netizens [1], therefore its Web 2.0 market is so attractive that many sources of venture capital flow into the Chinese Web 2.0 market and there are also a lot of new Web 2.0 companies in China. However, the development of Web 2.0 in China is accompanied by some problems and obstacles. In this paper, we will mainly discuss Web 2.0 applications in China, with their current problems and future development trends.

  18. A Compton camera for spectroscopic imaging from 100keV to 1MeV

    Science.gov (United States)

    Earnhart, Jonathan Raby Dewitt

    The objective of this work is to investigate Compton camera technology for spectroscopic imaging of gamma rays in the 100keV to 1MeV range. An efficient, specific purpose Monte Carlo code was developed to investigate the image formation process in Compton cameras. The code is based on a pathway sampling technique with extensive use of variance reduction techniques. The code includes detailed Compton scattering physics, including incoherent scattering functions, Doppler broadening, and multiple scattering. Experiments were performed with two different camera configurations for a scene containing a 75Se source and a 137Cs source. The first camera was based on a fixed silicon detector in the front plane and a CdZnTe detector mounted in the stage. The second camera configuration was based on two CdZnTe detectors. Both systems were able to reconstruct images of 75Se, using the 265keV line, and 137Cs, using the 662keV line. Only the silicon-CdZnTe camera was able to resolve the low intensity 400keV line of 75Se. Neither camera was able to reconstruct the 75Se source location using the 136keV line. The energy resolution of the silicon-CdZnTe camera system was 4% at 662keV. This camera reproduced the location of the 137Cs source by event circle image reconstruction with angular resolutions of 10° for a source on the camera axis and 14° for a source 30° off axis. Typical detector pair efficiencies were measured as 3 x 10-11 at 662keV. The dual CdZnTe camera had an energy resolution of 3.2% at 662keV. This camera reproduced the location of the 137Cs source by event circle image reconstruction with angular resolutions of 8° for a source on the camera axis and 12° for a source 20° off axis. Typical detector pair efficiencies were measured as 7 x 10-11 at 662keV. Of the two prototype camera configurations tested, the silicon-CdZnTe configuration had superior imaging characteristics. This configuration is less sensitive to effects caused by source decay cascades and random

  19. Ultra wideband reflector antenna log-periodic feed with operating frequency range 1–20 GHz.

    Directory of Open Access Journals (Sweden)

    F. F. Dubrovka

    2010-05-01

    Full Text Available Results of modeling and optimization of electric characteristics of ultra wideband reflector antenna log-periodic feed, based on two log-periodic antennas array for operating over frequency range 1 -20 GHz, are presented.

  20. Using Web 2.0 to Collaborate

    Science.gov (United States)

    Buechler, Scott

    2010-01-01

    Web 2.0 is not only for kids anymore, businesses are using it, too. Businesses are adopting Web 2.0 technology for a variety of purposes. In this article, the author discusses how he incorporates Web 2.0 into his business communications course. He describes a project that has both individual and collaborative elements and requires extensive…

  1. 22 CFR 20.2 - Funding.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Funding. 20.2 Section 20.2 Foreign Relations DEPARTMENT OF STATE PERSONNEL BENEFITS FOR CERTAIN FORMER SPOUSES § 20.2 Funding. Benefits under this part are paid from the Fund maintained by the Secretary of the Treasury pursuant to section 802 of the...

  2. Using Web 2.0 to Collaborate

    Science.gov (United States)

    Buechler, Scott

    2010-01-01

    Web 2.0 is not only for kids anymore, businesses are using it, too. Businesses are adopting Web 2.0 technology for a variety of purposes. In this article, the author discusses how he incorporates Web 2.0 into his business communications course. He describes a project that has both individual and collaborative elements and requires extensive…

  3. Bibliotheek 2.0 is een houding

    NARCIS (Netherlands)

    Schram, Hilda

    2007-01-01

    In de bibliotheek 2.0 worden web 2.0-technologieën op de bibliotheek toegepast. 2.0 is niet een nieuw theoretisch concept, maar een beschrijving van nieuwe of al langer bestaande internetdiensten waarvan openheid, meerrichtingsverkeer en gemakkelijke toepasbaarheid de belangrijkste kenmerken zijn. T

  4. 29 CFR 20.2 - Definitions.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 1 2010-07-01 2010-07-01 true Definitions. 20.2 Section 20.2 Labor Office of the Secretary of Labor FEDERAL CLAIMS COLLECTION Disclosure of Information to Credit Reporting Agencies § 20.2... excess of $100, arising from loans, loan guarantees, overpayments, fines, penalties or other causes....

  5. 7 CFR 20.2 - Administration.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Administration. 20.2 Section 20.2 Agriculture Office of the Secretary of Agriculture EXPORT SALES REPORTING REQUIREMENTS § 20.2 Administration. The regulations of this part will be administered by the Foreign Agricultural Service (FAS) under the...

  6. New acceptor-bridge-donor strategy for enhancing NLO response with long-range excess electron transfer from the NH2...M/M3O donor (M = Li, Na, K) to inside the electron hole cage C20F19 acceptor through the unusual σ chain bridge (CH2)4.

    Science.gov (United States)

    Bai, Yang; Zhou, Zhong-Jun; Wang, Jia-Jun; Li, Ying; Wu, Di; Chen, Wei; Li, Zhi-Ru; Sun, Chia-Chung

    2013-04-01

    Using the strong electron hole cage C20F19 acceptor, the NH2...M/M3O (M = Li, Na, and K) complicated donors with excess electron, and the unusual σ chain (CH2)4 bridge, we construct a new kind of electride molecular salt e(-)@C20F19-(CH2)4-NH2...M(+)/M3O(+) (M = Li, Na, and K) with excess electron anion inside the hole cage (to be encapsulated excess electron-hole pair) serving as a new A-B-D strategy for enhancing nonlinear optical (NLO) response. An interesting push-pull mechanism of excess electron generation and its long-range transfer is exhibited. The excess electron is pushed out from the (super)alkali atom M/M3O by the lone pair of NH2 in the donor and further pulled inside the hole cage C20F19 acceptor through the efficient long σ chain (CH2)4 bridge. Owing to the long-range electron transfer, the new designed electride molecular salts with the excess electron-hole pair exhibit large NLO response. For the e(-)@C20F19-(CH2)4-NH2...Na(+), its large first hyperpolarizability (β0) reaches up to 9.5 × 10(6) au, which is about 2.4 × 10(4) times the 400 au for the relative e(-)@C20F20...Na(+) without the extended chain (CH2)4-NH2. It is shown that the new strategy is considerably efficient in enhancing the NLO response for the salts. In addition, the effects of different bridges and alkali atomic number on β0 are also exhibited. Further, three modulating factors are found for enhancing NLO response. They are the σ chain bridge, bridge-end group with lone pair, and (super)alkali atom. The new knowledge may be significant for designing new NLO materials and electronic devices with electrons inside the cages. They may also be the basis of establishing potential organic chemistry with electron-hole pair.

  7. Web2.0 Era of E-learning2.0%Web2.0时代的E-learning2.0

    Institute of Scientific and Technical Information of China (English)

    邓国民

    2008-01-01

    web 2.0给我们带来了网络思维和网络应用方法的变革,也为 E-learning的教学模式提供了更多的支持,它将促成E-learning 2.0的产生.本文首先介绍Web 2.0的核心内容和特点,然后分析讨论了web 2.0在E-learning中的应用,最后对E-learning 2.0的特点和优势进行了总结.

  8. Web 2.0 i undervisningen

    DEFF Research Database (Denmark)

    Liburd, Janne J.; Christensen, Inger-Marie F.

    2011-01-01

    Temahæfte om web 2.0, der formidler viden om og inspiration til at arbejde med web 2.0 teknologier i videregående uddannelser. Hæftet introducerer sociale medier og web 2.0, og der redegøres for teoretisk funderede læreprocesser med web 2.0, og hvorledes disse kan indtænkes i undervisningsforløb....... Hæftet præsenterer endvidere en metode til design af læringsaktiviteter med web 2.0, og giver en række eksempler på konkrete forløb....

  9. The PLATO 2.0 Mission

    CERN Document Server

    Rauer, H; Aerts, C; Appourchaux, T; Benz, W; Brandeker, A; Christensen-Dalsgaard, J; Deleuil, M; Gizon, L; Güdel, M; Janot-Pacheco, E; Mas-Hesse, M; Pagano, I; Piotto, G; Pollacco, D; Santos, N C; Smith, A; -C., J; Suárez,; Szabó, R; Udry, S; Adibekyan, V; Alibert, Y; Almenara, J -M; Amaro-Seoane, P; Eiff, M Ammler-von; Antonello, E; Ball, W; Barnes, S; Baudin, F; Belkacem, K; Bergemann, M; Birch, A; Boisse, I; Bonomo, A S; Borsa, F; Brandão, I M; Brocato, E; Brun, S; Burleigh, M; Burston, R; Cabrera, J; Cassisi, S; Chaplin, W; Charpinet, S; Chiappini, C; Csizmadia, Sz; Cunha, M; Damasso, M; Davies, M B; Deeg, H J; Fialho, F de Oliveira; DÍaz, R F; Dreizler, S; Dreyer, C; Eggenberger, P; Ehrenreich, D; Eigmüller, P; Erikson, A; Farmer, R; Feltzing, S; Figueira, P; Forveille, T; Fridlund, M; García, R; Giuffrida, G; Godolt, M; da Silva, J Gomes; Goupil, M -J; Granzer, T; Grenfell, J L; Grotsch-Noels, A; Günther, E; Haswell, C A; Hatzes, A P; Hébrard, G; Hekker, S; Helled, R; Heng, K; Jenkins, J M; Khodachenko, M L; Kislyakova, K G; Kley, W; Kolb, U; Krivova, N; Kupka, F; Lammer, H; Lanza, A F; Lebreton, Y; Magrin, D; Marcos-Arenal, P; Marrese, P M; Marques, J P; Martins, J; Mathis, S; Mathur, S; Messina, S; Miglio, A; Montalban, J; Montalto, M; Monteiro, M J P F G; Moradi, H; Moravveji, E; Mordasini, C; Morel, T; Mortier, A; Nascimbeni, V; Nielsen, M B; Noack, L; Norton, A J; Ofir, A; Oshagh, M; Ouazzani, R -M; Pápics, P; Parro, V C; Petit, P; Plez, B; Poretti, E; Quirrenbach, A; Ragazzoni, R; Raimondo, G; Rainer, M; Reese, D R; Redmer, R; Reffert, S; Rojas-Ayala, B; Roxburgh, I W; Solanki, S K; Salmon, S; Santerne, A; Schneider, J; Schou, J; Schuh, S; Schunker, H; Silva-Valio, A; Silvotti, R; Skillen, I; Snellen, I; Sohl, F; Sousa, A S; Sozzetti, A; Stello, D; Strassmeier, K G; Švanda, M; Szabó, G M; Tkachenko, A; Valencia, D; van Grootel, V; Vauclair, S D; Ventura, P; Wagner, F W; Walton, N A; Weingrill, J; Werner, S C; Wheatley, P J; Zwintz, K

    2013-01-01

    PLATO 2.0 is a mission candidate for ESA's M3 launch opportunity (2022/24). It addresses fundamental questions such as: How do planetary systems form and evolve? Are there other systems with planets like ours, able to develop life? The PLATO 2.0 instrument consists of 34 small aperture telescopes providing a wide field-of-view and a large photometric magnitude range. It targets bright stars in wide fields to detect and characterize planets down to Earth-size by photometric transits, whose masses can then be determined by ground-based radial-velocity follow-up measurements. Asteroseismology will be performed for stars <=11mag to obtain highly accurate stellar parameters, including masses and ages. The combination of bright targets and asteroseismology results in high accuracy for the bulk planet parameters: 2%, 4-10% and 10% for planet radii, masses and ages, respectively. The foreseen baseline observing strategy includes two long pointings (2-3 years) to detect and bulk characterize planets reaching into t...

  10. 700 keV Ni{sup +2} ions induced modification in structural, surface, magneto-optic and optical properties of ZnO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Fiaz Khan, M. [Laser and Optronics Centre, Department of Physics, University of Engineering and Technology, Lahore (Pakistan); Siraj, K., E-mail: khurram.uet@gmail.com [Laser and Optronics Centre, Department of Physics, University of Engineering and Technology, Lahore (Pakistan); Anwar, M.S. [Department of Physics, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences (LUMS), Opposite Sector U, D.H.A. Lahore 54792 (Pakistan); Irshad, M. [Laser and Optronics Centre, Department of Physics, University of Engineering and Technology, Lahore (Pakistan); Hussain, J. [National Centre for Physics, Islamabad (Pakistan); Faiz, H.; Majeed, S. [Laser and Optronics Centre, Department of Physics, University of Engineering and Technology, Lahore (Pakistan); Dosmailov, M.; Patek, J.; Pedarnig, J.D. [Institute of Applied Physics, Johannes Kepler University Linz (Austria); Rafique, M.S. [Laser and Optronics Centre, Department of Physics, University of Engineering and Technology, Lahore (Pakistan); Naseem, S. [Center of Excellence in Solid State Physics, University of Punjab, Lahore (Pakistan)

    2016-02-01

    Highlights: • 700 keV ion irradiation on ZnO thin films was done at different ion fluence. • XRD results showed improved crystallinity. • At lower fluence the microparticles were observed whereas ZnO micro rods were observed at higher fluences. • The Verdet constant and optical band gap energy of ZnO thin films are also well modified. - Abstract: We investigate the effect of 700 keV Ni{sup +2} ions irradiation at different ion fluences (1 × 10{sup 13}, 1 × 10{sup 14}, 2 × 10{sup 14}, 5 × 10{sup 14} ions/cm{sup 2}) on the structural, surface, magneto-optic and optical properties of ZnO thin films. The X-ray diffraction (XRD) results show improved crystallinity when ion fluence is increased to 2 × 10{sup 14} ions/cm{sup 2}, while deterioration is observed at the highest ion fluence of 5 × 10{sup 14} ions/cm{sup 2}. Scanning electron micrographs (SEM) show the formation of small grains at ion fluence 1 × 10{sup 13} ions/cm{sup 2}, micro-rods at fluences 1 × 10{sup 14} and 2 × 10{sup 14} ions/cm{sup 2} and ultimate fracturing of thin film surface at ion fluence 5 × 10{sup 14} ions/cm{sup 2}. Faraday rotation measurements are also performed and show a decrease in Verdet constant from 53 to 31 rad/(T-m) when irradiated at 1 × 10{sup 13} ions/cm{sup 2}, increasing up to 45 rad/(T-m) at 2 × 10{sup 14} ions/cm{sup 2}, and then decreasing again to 36 rad/(T-m) at 5 × 10{sup 14} ions/cm{sup 2}. The optical band gap energy of the films is determined using spectroscopic ellipsometry, which shows an increase in optical band gap energy (E{sub g}) from 3.04 eV to 3.19 eV when the fluence increases to 2 × 10{sup 14} ions/cm{sup 2} and a decrease to 3 eV at fluence 5 × 10{sup 14} ions/cm{sup 2}. We argue that these properties can be explained using ion heating effect of thin films.

  11. X-ray detection with Micromegas with background levels below 10$^{-6}$ keV$^{-1}$cm$^{-2}$s$^{-1}$

    CERN Document Server

    Aune, S; Calvet, D.; Dafni, T.; Diago, A.; Druillole, F.; Fanourakis, G.; Ferrer-Ribas, E.; Galán, J.; García, J.A.; Gardikiotis, A.; Garza, J.G.; Geralis, T.; Giomataris, I.; Gómez, H.; González-Díaz, D.; Herrera, D.C.; Iguaz, F.J.; Irastorza, I.G.; Jourde, D.; Luzón, G.; Mirallas, H.; Mols, J.P.; Papaevangelou, T.; Rodríguez, A.; Seguí, L.; Tomás, A.; Vafeiadis, T.; Yildiz, S.C.

    2013-01-01

    Micromegas detectors are an optimum technological choice for the detection of low energy x-rays. The low background techniques applied to these detectors yielded remarkable background reductions over the years, being the CAST experiment beneficiary of these developments. In this document we report on the latest upgrades towards further background reductions and better understanding of the detectors' response. The upgrades encompass the readout electronics, a new detector design and the implementation of a more efficient cosmic muon veto system. Background levels below 10$^{-6}$keV$^{-1}$cm$^{-2}$s$^{-1}$ have been obtained at sea level for the first time, demonstrating the feasibility of the expectations posed by IAXO, the next generation axion helioscope. Some results obtained with a set of measurements conducted in the x-ray beam of the CAST Detector Laboratory will be also presented and discussed.

  12. Flat Crystal x-ray Spectrometer for Quantitative Spectral Measurement in the 2-5 keV Region

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yang; ZHANG Ji-Yan; YANG Jia-Min; WEI Min-Xi; DENG Bo; ZHU Tuo; HU Zhi-Min; XIONG Gang; SHANG Wan-Li; KUANG Long-Yu; YANG Guo-Hong

    2011-01-01

    @@ A technique of fiat crystal x-ray spectrometer for quantitative spectral measurement is described.For the flat crystal spectrograph geometry, the quantitative reduction of relating the CCD counts back to the photon flux from the x-ray source is established.The absolute calibrations of the integral diffraction coefficients of the crystal and the CCD sensitivity make it possible to measure absolute photons flux within the energy range of 2000-5000 eV.The uncertainty analysis of the calibrations is carried out to obtain the energy resolved uncertainties of crystal and CCD.Thus, the experimentai spectra with spectral resolved intensity uncertainties are available.Then, a performing experiment of laser-produced Ti plasma is carried out and the absolute x-ray spectra with intensity uncertainty less than 8.5% are obtained.The technique is promising for absolute spectral measurement of high temperature plasmas in a kilo-electron-volt region.

  13. Hard X-ray detection of the black hole candidates 4U 1630-47 and IGR J17091-3624 up to 200 keV with INTEGRAL

    DEFF Research Database (Denmark)

    Bodaghee, A.; Kuulkers, E.; Tomsick, J. A.

    2012-01-01

    is statistically compatible with the source flux measured by Swift-BAT on that date in a similar energy range (28+/-4 mCrab: http://heasarc.nasa.gov/docs/swift/results/transients ). In JEM-X, 4U 1630-47 has count rates of 94.0+/-2.2 cts/s (534+/-13 mCrab, 43-sigmas) in the 3-10 keV band, and 6.4+/-0.9 cts/s (90...... is lower than the 24+/-5 mCrab measured by Swift-BAT on that date in the 15-50 keV band, while the hard-band flux is higher than the value in the same energy range during the previous outburst (20+/-3 mCrab: ATel #3916). This source was outside the field of view of JEM-X. The source spectrum can be fit...... with a power law (Gamma = 1.7+/-0.4; red. Chi^2/dof = 1.5/10; observed flux = 6e-10 erg/cm2/s in 20-100 keV) up to ~200 keV with no evidence for a cutoff. It was also detected above the 6-sigma level in both ISGRI bands during the previous observation of the field (rev. 1207). A possible transition to the hard...

  14. FRAMES-2.0 Software System: Frames 2.0 Pest Integration (F2PEST)

    Energy Technology Data Exchange (ETDEWEB)

    Castleton, Karl J.; Meyer, Philip D.

    2009-06-17

    The implementation of the FRAMES 2.0 F2PEST module is described, including requirements, design, and specifications of the software. This module integrates the PEST parameter estimation software within the FRAMES 2.0 environmental modeling framework. A test case is presented.

  15. Neutron-induced fission cross-section measurement of 234U with quasi-monoenergetic beams in the keV and MeV range using micromegas detectors

    Science.gov (United States)

    Tsinganis, A.; Kokkoris, M.; Vlastou, R.; Kalamara, A.; Stamatopoulos, A.; Kanellakopoulos, A.; Lagoyannis, A.; Axiotis, M.

    2017-09-01

    Accurate data on neutron-induced fission cross-sections of actinides are essential for the design of advanced nuclear reactors based either on fast neutron spectra or alternative fuel cycles, as well as for the reduction of safety margins of existing and future conventional facilities. The fission cross-section of 234U was measured at incident neutron energies of 560 and 660 keV and 7.5 MeV with a setup based on `microbulk' Micromegas detectors and the same samples previously used for the measurement performed at the CERN n_TOF facility (Karadimos et al., 2014). The 235U fission cross-section was used as reference. The (quasi-)monoenergetic neutron beams were produced via the 7Li(p,n) and the 2H(d,n) reactions at the neutron beam facility of the Institute of Nuclear and Particle Physics at the `Demokritos' National Centre for Scientific Research. A detailed study of the neutron spectra produced in the targets and intercepted by the samples was performed coupling the NeuSDesc and MCNPX codes, taking into account the energy spread, energy loss and angular straggling of the beam ions in the target assemblies, as well as contributions from competing reactions and neutron scattering in the experimental setup. Auxiliary Monte-Carlo simulations were performed with the FLUKA code to study the behaviour of the detectors, focusing particularly on the reproduction of the pulse height spectra of α-particles and fission fragments (using distributions produced with the GEF code) for the evaluation of the detector efficiency. An overview of the developed methodology and preliminary results are presented.

  16. Scaling functions of two-neutron separation energies of $^{20}C$ with finite range potentials

    CERN Document Server

    Shalchi, M A; Yamashita, M T; Tomio, Lauro; Frederico, T

    2015-01-01

    The behaviour of an Efimov excited state is studied within a three-body Faddeev formalism for a general neutron-neutron-core system, where neutron-core is bound and neutron-neutron is unbound, by considering zero-ranged as well as finite-ranged two-body interactions. For the finite-ranged interactions we have considered a one-term separable Yamaguchi potential. The main objective is to study range corrections in a scaling approach, with focus in the exotic carbon halo nucleus $^{20}C$.

  17. Scaling functions of two-neutron separation energies of 20C with finite range potentials

    Science.gov (United States)

    Shalchi, M. A.; Hadizadeh, M. R.; Yamashita, M. T.; Tomio, Lauro; Frederico, T.

    2016-03-01

    The behaviour of an Efimov excited state is studied within a three-body Faddeev formalism for a general neutron-neutron-core system, where neutron-core is bound and neutron-neutron is unbound, by considering zero-ranged as well as finite-ranged two-body interactions. For the finite-ranged interactions we have considered a one-term separable Yamaguchi potential. The main objective is to study range corrections in a scaling approach, with focus in the exotic carbon halo nucleus 20C.

  18. Scaling functions of two-neutron separation energies of 20C with finite range potentials

    Directory of Open Access Journals (Sweden)

    Shalchi M. A.

    2016-01-01

    Full Text Available The behaviour of an Efimov excited state is studied within a three-body Faddeev formalism for a general neutron-neutron-core system, where neutron-core is bound and neutron-neutron is unbound, by considering zero-ranged as well as finite-ranged two-body interactions. For the finite-ranged interactions we have considered a one-term separable Yamaguchi potential. The main objective is to study range corrections in a scaling approach, with focus in the exotic carbon halo nucleus 20C.

  19. Sputtering of cryogenic films of hydrogen by keV ions

    DEFF Research Database (Denmark)

    Schou, Jørgen; Hilleret, Noel

    2009-01-01

    The sputtering yield induced by keV hydrogen ions measured at CERN and at Risø National Laboratory for solid H2 and D2 at temperatures below 4.2 K decreases with increasing film thickness from about 100 x 10(15)molecules/cm2. For a film thickness comparable to or larger than the ion range the dat...

  20. DISFRAC Version 2.0 Users Guide

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, Kristine B [ORNL; Erickson, Marjorie A [ORNL; Williams, Paul T [ORNL; Klasky, Hilda B [ORNL; Bass, Bennett Richard [ORNL

    2013-01-01

    DISFRAC is the implementation of a theoretical, multi-scale model for the prediction of fracture toughness in the ductile-to-brittle transition temperature (DBTT) region of ferritic steels. Empirically-derived models of the DBTT region cannot legitimately be extrapolated beyond the range of existing fracture toughness data. DISFRAC requires only tensile properties and microstructural information as input, and thus allows for a wider range of application than empirical, toughness data dependent models. DISFRAC is also a framework for investigating the roles of various microstructural and macroscopic effects on fracture behavior, including carbide particle sizes, grain sizes, strain rates, and material condition. DISFRAC s novel approach is to assess the interaction effects of macroscopic conditions (geometry, loading conditions) with variable microstructural features on cleavage crack initiation and propagation. The model addresses all stages of the fracture process, from microcrack initiation within a carbide particle, to propagation of that crack through grains and across grain boundaries, finally to catastrophic failure of the material. The DISFRAC procedure repeatedly performs a deterministic analysis of microcrack initiation and propagation within a macroscopic crack plastic zone to calculate a critical fracture toughness value for each microstructural geometry set. The current version of DISFRAC, version 2.0, is a research code for developing and testing models related to cleavage fracture and transition toughness. The various models and computations have evolved significantly over the course of development and are expected to continue to evolve as testing and data collection continue. This document serves as a guide to the usage and theoretical foundations of DISFRAC v2.0. Feedback is welcomed and encouraged.

  1. Interaction between Solid Nitrogen and 1-3-keV Electrons

    DEFF Research Database (Denmark)

    Schou, Jørgen; Sørensen, H.

    1978-01-01

    Experimental studies were made of the interaction between solid nitrogen and beams of 1-2-keV electrons. The projected range for the electrons was measured by means of the mirror-substrate method (gold substrate), giving the result 9.02×1016 E1.75 molecules/cm2 with the energy given in ke......V. At 3 keV, the SEE coefficient is 12 times that for solid deuterium. This is attributed partly to the larger production rate for low-energy electrons in nitrogen and partly to the larger escape probability for these electrons. Moreover, measurements were made of the electron-reflection coefficient, both......V. The escape depth for secondary electrons was studied by means of the equivalent-substrate method (carbon substrate). The results varied from 280 Å at 1 keV to 400 Å at 3 keV. Measurements were also made of the secondary-electron-emission coefficient, which varied from 2.3 el/el at 1 keV to 1.2 el/el at 3 ke...

  2. Web 2.0: A Strategy Guide

    CERN Document Server

    Shuen, Amy

    2008-01-01

    Web 2.0 makes headlines, but how does it make money? This concise guide explains what's different about Web 2.0 and how those differences can improve the bottom line. Whether you're an executive, a small business owner, or an entrepreneur, Web 2.0: A Strategy Guide illustrates through real life examples how various businesses are creating new opportunities on today's Web. This book is about strategy rather than the technology itself.

  3. Web 2.0 i undervisningen

    DEFF Research Database (Denmark)

    Liburd, Janne J.; Christensen, Inger-Marie F.

    2011-01-01

    Temahæfte om web 2.0, der formidler viden om og inspiration til at arbejde med web 2.0 teknologier i videregående uddannelser. Hæftet introducerer sociale medier og web 2.0, og der redegøres for teoretisk funderede læreprocesser med web 2.0, og hvorledes disse kan indtænkes i undervisningsforløb........ Hæftet præsenterer endvidere en metode til design af læringsaktiviteter med web 2.0, og giver en række eksempler på konkrete forløb.......Temahæfte om web 2.0, der formidler viden om og inspiration til at arbejde med web 2.0 teknologier i videregående uddannelser. Hæftet introducerer sociale medier og web 2.0, og der redegøres for teoretisk funderede læreprocesser med web 2.0, og hvorledes disse kan indtænkes i undervisningsforløb...

  4. Teaching PBL with Web 2.0

    DEFF Research Database (Denmark)

    Dohn, Nina Bonderup; Buus, Lillian

    2013-01-01

    of competences necessary for participating in contemporary society. In this article we report on a study of three cases where web 2.0 activities have been introduced into PBL settings. Our focus is the unexpected challenges teachers may face due to inherent tensions between the practice logic of the educational...... system and that of web 2.0-practices. The study documents the development of viable ways of making use of web 2.0-mediated activities in support of a PBL approach and thus provides existence proof that web 2.0 activities may contribute constructively and productively to learning within a PBL perspective...

  5. A search for 2-photon emission from the 662 keV state in ^137Ba using Gammasphere

    Science.gov (United States)

    Lister, C. J.; McCutchan, E. A.; Moran, K.; Zhu, S.; Carpenter, M. P.; Greene, J. P.; Millener, J. D.; Sutter, R. J.; Alburger, D. E.

    2012-10-01

    Two photon decays from excited nuclear states provide an interesting test both of QED and nuclear structure. It has been extensively studied for cases where one photon decay is forbidden [1]. Two photon decay in direct competition with the first order process has never been convincingly demonstrated. Nonetheless, observation of this decay will provide additional challenging tests for experiment and theory. The ^137Ba case is particularly interesting as the decay has high multipolarity, M4, so the 2-photon process can have contributions from both quadrupole-quadrupole and dipole-octupole multipolarities. Gammasphere is the perfect tool for this investigation, having good energy resolution, good efficiency, good coverage of angles, and sufficient granularity to minimize pile-up and count-rate difficulties. A short test experiment showed the power of Gammasphere and the dauntingly high Compton scattering background that need suppression. However, new calculations and new measurements from Brookhaven suggest that the two photon branch is ˜2 x 10-6 and should be measurable. This work was supported by DOE contracts, DE-FG02-94ER40848, DE-AC02-06CH11357 and DE-AC02-98CH10946.[4pt] [1] J. Kramp, et. al, Nucl. Phys. A474 (1987) 412

  6. In Situ TEM Study of Microstructure Evolution of Zr-Nb-Fe Alloy Irradiated by 800 keV Kr(2+) Ions.

    Science.gov (United States)

    Lei, Penghui; Ran, Guang; Liu, Chenwei; Ye, Chao; Lv, Dong; Lin, Jianxin; Wu, Yizhen; Xu, Jiangkun

    2017-04-22

    The microstructure evolution of Zr-1.1Nb-1.51Fe-0.26Cu-0.72Ni zirconium alloy, irradiated by 800 keV Kr(2+) ions at 585 K using the IVEM-Tandem Facility at Argonne National Laboratory, was observed by in situ transmission electron microscopy. A number of β-Nb precipitates with a body-centered cubic (BCC) structure were distributed in the as-received zirconium alloy with micrometer-size grains. Kr(2+) ion irradiation induced the growth of β-Nb precipitates, which could be attributed to the segregation of the dissolved niobium atoms in the zirconium lattice and the migration to the existing precipitates. The size of precipitates was increased with increasing Kr(2+) ion fluence. During Kr(2+) iron irradiation, the zirconium crystals without Nb precipitates tended to transform to the nanocrystals, which was not observed in the zirconium crystals with Nb nanoparticles. The existing Nb nanoparticles were the key factor that constrained the nanocrystallization of zirconium crystals. The thickness of the formed Zr-nanocrystal layer was about 300 nm, which was consistent with the depth of Kr(2+) iron irradiation. The mechanism of the precipitate growth and the formation of zirconium nanocrystal was analyzed and discussed.

  7. GEM Building Taxonomy (Version 2.0)

    Science.gov (United States)

    Brzev, S.; Scawthorn, C.; Charleson, A.W.; Allen, L.; Greene, M.; Jaiswal, Kishor; Silva, V.

    2013-01-01

    This report documents the development and applications of the Building Taxonomy for the Global Earthquake Model (GEM). The purpose of the GEM Building Taxonomy is to describe and classify buildings in a uniform manner as a key step towards assessing their seismic risk, Criteria for development of the GEM Building Taxonomy were that the Taxonomy be relevant to seismic performance of different construction types; be comprehensive yet simple; be collapsible; adhere to principles that are familiar to the range of users; and ultimately be extensible to non-buildings and other hazards. The taxonomy was developed in conjunction with other GEM researchers and builds on the knowledge base from other taxonomies, including the EERI and IAEE World Housing Encyclopedia, PAGER-STR, and HAZUS. The taxonomy is organized as a series of expandable tables, which contain information pertaining to various building attributes. Each attribute describes a specific characteristic of an individual building or a class of buildings that could potentially affect their seismic performance. The following 13 attributes have been included in the GEM Building Taxonomy Version 2.0 (v2.0): 1.) direction, 2.)material of the lateral load-resisting system, 3.) lateral load-resisting system, 4.) height, 5.) date of construction of retrofit, 6.) occupancy, 7.) building position within a block, 8.) shape of the building plan, 9.) structural irregularity, 10.) exterior walls, 11.) roof, 12.) floor, 13.) foundation system. The report illustrates the pratical use of the GEM Building Taxonomy by discussing example case studies, in which the building-specific characteristics are mapped directly using GEM taxonomic attributes and the corresponding taxonomic string is constructed for that building, with "/" slash marks separating attributes. For example, for the building shown to the right, the GEM Taxonomy string is: DX1/MUR+CLBRS+MOCL2/LWAL3/

  8. Theoretical Study of Secondary Electron Yield in Energy Range of 10 ~ 30 keV%10~30 keV二次电子发射系数的表达式

    Institute of Scientific and Technical Information of China (English)

    谢爱根; 王祖松; 刘战辉; 詹煜; 吴红艳

    2013-01-01

    Here we addressed the theoretical subject of the secondary electron emission,in the energy range of 10 ~30keY.First,the formulae of the maximum second electron yield (δm),and the average number of secondary electrons released per primary electron with fairly high incident energy (δPE) were derived,respectively.Next,a general expression of δ in terms of the variables,including δm,atomic number,atomic weight,material density,back-scattering coefficient (γ),back-scattering coefficient at high energy (η),parameter A,energy exponent (n),and the incident energy of primary electron,was obtained,on the basis of the influence of δm and δPE on the secondary electron yield at high energy (δ).The parameter A and energy exponent n,in the energy range of 10 ~ 30 keV for some emitters of interest,were modeled and calculated with the software package ESTAR.The experimentally measured and calculated results of δ with the general formula were compared.The comparison result shows that when it comes to the secondary electron emission in the energy range of 10~ 30 keV,the newly-developed general formula of δ works fairly well for metals,semi-metals and element semiconductors.%根据二次电子发射的主要物理过程和特性,推导出最大二次电子发射系数(δm)的表达式.还推导出平均每个高能原电子发射的二次电子数(δPE)的表达式.根据δPE、δm和高能二次电子发射系数(δ)之间的关系,推导出以δm、原子序数、原子质量数、物质密度、背散射系数、高能背散射系数、参数A、能量幂次(n)和原电子入射能量为变量δ的通式.用ESTR程序计算出一些材料的10~ 30 keV能量范围内的参数A和n.用该通式计算出δ并与相应的实验值进行了比较,结果表明,成功地推导出金属、半金属和元素半导体10~ 30 keV的δ通式.

  9. The structural behavior of SrTiO{sub 3} under 400 keV Ne{sup 2+} ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Su, X.; Liu, C.G.; Yang, D.Y.; Wen, J.; Chen, L.J.; Xu, D.P.; Li, Y.H. [Lanzhou University, School of Nuclear Science and Technology, Lanzhou (China); Fu, E.G. [Peking University, State Key Laboratory of Nuclear Physics and Technology, Beijing (China); Zhang, J. [Xiamen University, School of Energy Research, Xiamen (China); Wang, Y.Q. [Los Alamos National Laboratory, Materials Science and Technology Division, Los Alamos, NM (United States)

    2015-11-15

    The structural behavior of polycrystalline perovskite SrTiO{sub 3} under 400 keV Ne{sup 2+} ion irradiation at both liquid nitrogen (LN{sub 2}) and room temperature (RT) has been investigated. The grazing incident X-ray diffraction technique was applied to examine the radiation-induced structural evolution. The radiation behavior of SrTiO{sub 3} depends strongly on the irradiation temperature. At LN{sub 2} temperature, the samples exhibit significant lattice swelling and amorphization, whereas at RT, the lattice swelling is much less conspicuous and no amorphization is detected even at the highest irradiation dose of 5.0 dpa. Nevertheless, Ne{sup 2+} irradiation induces peak splitting in XRD patterns at both temperatures. Furthermore, first-principle calculations have been performed with VASP, involving possible defect types, to identify which defect is responsible for the radiation effect of SrTiO{sub 3}. The results reveal that the oxygen vacancy defect is the most likely to contribute to the radiation behavior of SrTiO{sub 3}. (orig.)

  10. Trust, Voice, and Library 2.0

    Science.gov (United States)

    Watkins, Candice

    2009-01-01

    Web 2.0 is a constant and growing theme in the library field. This article describes a social networking site based on a Web 2.0 infused course management system (CMS) developed by Clatsop Community College in Astoria, Oregon.

  11. Conservation and development 2.0

    NARCIS (Netherlands)

    Büscher, Bram

    2016-01-01

    An increasing amount of interactive '2.0' crowdsourcing platforms raise awareness and funds for conservation and development projects worldwide. By enabling two-way online collaboration and communication, these 'conservation and development 2.0' platforms hoped to provide new impetus and popular

  12. Public health and Web 2.0.

    Science.gov (United States)

    Hardey, Michael

    2008-07-01

    This article examines the nature and role of Web 2.0 resources and their impact on health information made available though the Internet. The transition of the Web from version one to Web 2.0 is described and the main features of the new Web examined. Two characteristic Web 2.0 resources are explored and the implications for the public and practitioners examined. First, what are known as 'user reviews' or 'user testimonials', which allow people to comment on the health services delivered to them, are described. Second, new mapping applications that take advantage of the interactive potential of Web 2.0 and provide tools to visualize complex data are examined. Following a discussion of the potential of Web 2.0, it is concluded that it offers considerable opportunities for disseminating health information and creating new sources of data, as well as generating new questions and dilemmas.

  13. Electron capture and transfer-ionization processes in {sup 4}He{sup 2+}+Ar collision at 12.5 keV amu{sup -1}

    Energy Technology Data Exchange (ETDEWEB)

    Moretto-Capelle, P.; Bordenave-Montesquieu, D.; Bordenave-Montesquieu, A.; Benhenni, M. [Laboratoire Collisions, Agregats, Reactivite, IRSAMC, UMR 5589 CNRS and Universite Paul Sabatier, 31062 Toulouse Cedex (France)

    1998-05-14

    Electron emission in the {sup 4}He{sup 2+}+Ar collisional system has been investigated at 35 deg. and 12.5 keV amu{sup -1} collision velocity, in coincidence with the recoil target ion charges. Direct single ionization is found to be negligible with respect to single-electron capture. Contributions of transfer-ionization processes are stressed in the production of Ar{sup 2+} to Ar{sup 4+} ions; those of direct ionization, double excitation of the target and double capture into autoionization states of helium are instead found to be much less probable. Among the two-electron processes which explain the formation of Ar{sup 2+} ions, the double capture into autoionizing states of helium remains unimportant with respect to a pure transfer ionization process (one captured electron plus one ionized electron). The measured predominant production of Ar{sup 3+} ions illustrates the role played by three-electron processes, mainly a two-electron transfer accompanied by a single-target ionization. Finally, the formation of Ar{sup 4+} ions is connected with more complex transfer ionization processes. A qualitative analysis of these results is made within the quasimolecular approach. (author). Letter-to-the-editor.

  14. Lensing substructure quantification in RXJ1131-1231: a 2 keV lower bound on dark matter thermal relic mass

    Science.gov (United States)

    Birrer, Simon; Amara, Adam; Refregier, Alexandre

    2017-05-01

    We study the substructure content of the strong gravitational lens RXJ1131-1231 through a forward modelling approach that relies on generating an extensive suite of realistic simulations. We use a semi-analytic merger tree prescription that allows us to stochastically generate substructure populations whose properties depend on the dark matter particle mass. These synthetic halos are then used as lenses to produce realistic mock images that have the same features, e.g. luminous arcs, quasar positions, instrumental noise and PSF, as the data. We then analyse the data and the simulations in the same way with summary statistics that are sensitive to the signal being targeted and are able to constrain models of dark matter statistically using Approximate Bayesian Computing (ABC) techniques. {In this work, we focus on the thermal relic mass estimate and fix the semi-analytic descriptions of the substructure evolution based on recent literature.} We are able, based on the HST data for RXJ1131-1231, to rule out a warm dark matter thermal relic mass below 2 keV at the 2σ confidence level.

  15. A Typology for Web 2.0

    DEFF Research Database (Denmark)

    Dalsgaard, Christian; Sorensen, Elsebeth Korsgaard

    2008-01-01

    Web 2.0 is a term used to describe recent developments on the World Wide Web. The term is often used to describe the increased use of the web for user-generated content, collaboration, and social networking. However, Web 2.0 is a weakly defined concept, and it is unclear exactly what kind...... of technologies it covers. The objective of the paper is to develop a typology that can be used to categorize Web 2.0 technologies. Further, the paper will discuss which of these technologies are unique to Web 2.0. Often, Web 2.0 is described by way of different kinds of software; for instance, blogs, wikis....... The typology suggested by this paper relates to four functions or use contexts, which are believed to be central to the potentials of Web 2.0: dialoging, networking and awareness-making, creating and sharing. Based on the typology, the paper identifies unique potentials of Web 2.0 in relation to design...

  16. ROMUSE 2.0 User Manual

    Energy Technology Data Exchange (ETDEWEB)

    Khuwaileh, Bassam [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Turinsky, Paul [North Carolina State Univ., Raleigh, NC (United States); Williams, Brian J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-04

    ROMUSE (Reduced Order Modeling Based Uncertainty/Sensitivity Estimator) is an effort within the Consortium for Advanced Simulation of Light water reactors (CASL) to provide an analysis tool to be used in conjunction with reactor core simulators, especially the Virtual Environment for Reactor Applications (VERA). ROMUSE is written in C++ and is currently capable of performing various types of parameters perturbations, uncertainty quantification, surrogate models construction and subspace analysis. Version 2.0 has the capability to interface with DAKOTA which gives ROMUSE access to the various algorithms implemented within DAKOTA. ROMUSE is mainly designed to interface with VERA and the Comprehensive Modeling and Simulation Suite for Nuclear Safety Analysis and Design (SCALE) [1,2,3], however, ROMUSE can interface with any general model (e.g. python and matlab) with Input/Output (I/O) format that follows the Hierarchical Data Format 5 (HDF5). In this brief user manual, the use of ROMUSE will be overviewed and example problems will be presented and briefly discussed. The algorithms provided here range from algorithms inspired by those discussed in Ref.[4] to nuclear-specific algorithms discussed in Ref. [3].

  17. LSST Science Book, Version 2.0

    CERN Document Server

    Allison, Julius; Andrew, John R; Angel, J Roger P; Armus, Lee; Arnett, David; Asztalos, S J; Axelrod, Tim S; Bailey, Stephen; Ballantyne, D R; Bankert, Justin R; Barkhouse, Wayne A; Barr, Jeffrey D; Barrientos, L Felipe; Barth, Aaron J; Bartlett, James G; Becker, Andrew C; Becla, Jacek; Beers, Timothy C; Bernstein, Joseph P; Biswas, Rahul; Blanton, Michael R; Bloom, Joshua S; Bochanski, John J; Boeshaar, Pat; Borne, Kirk D; Bradac, Marusa; Brandt, W N; Bridge, Carrie R; Brown, Michael E; Brunner, Robert J; Bullock, James S; Burgasser, Adam J; Burge, James H; Burke, David L; Cargile, Phillip A; Chandrasekharan, Srinivasan; Chartas, George; Chesley, Steven R; Chu, You-Hua; Cinabro, David; Claire, Mark W; Claver, Charles F; Clowe, Douglas; Connolly, A J; Cook, Kem H; Cooke, Jeff; Cooray, Asantha; Covey, Kevin R; Culliton, Christopher S; de Jong, Roelof; de Vries, Willem H; Debattista, Victor P; Delgado, Francisco; Dell'Antonio, Ian P; Dhital, Saurav; Di Stefano, Rosanne; Dickinson, Mark; Dilday, Benjamin; Djorgovski, S G; Dobler, Gregory; Donalek, Ciro; Dubois-Felsmann, Gregory; Durech, Josef; Eliasdottir, Ardis; Eracleous, Michael; Eyer, Laurent; Falco, Emilio E; Fan, Xiaohui; Fassnacht, Christopher D; Ferguson, Harry C; Fernandez, Yanga R; Fields, Brian D; Finkbeiner, Douglas; Figueroa, Eduardo E; Fox, Derek B; Francke, Harold; Frank, James S; Frieman, Josh; Fromenteau, Sebastien; Furqan, Muhammad; Galaz, Gaspar; Gal-Yam, A; Garnavich, Peter; Gawiser, Eric; Geary, John; Gee, Perry; Gibson, Robert R; Gilmore, Kirk; Grace, Emily A; Green, Richard F; Gressler, William J; Grillmair, Carl J; Habib, Salman; Haggerty, J S; Hamuy, Mario; Harris, Alan W; Hawley, Suzanne L; Heavens, Alan F; Hebb, Leslie; Henry, Todd J; Hileman, Edward; Hilton, Eric J; Hoadley, Keri; Holberg, J B; Holman, Matt J; Howell, Steve B; Infante, Leopoldo; Ivezic, Zeljko; Jacoby, Suzanne H; Jain, Bhuvnesh; R,; Jedicke,; Jee, M James; Jernigan, J Garrett; Jha, Saurabh W; Johnston, Kathryn V; Jones, R Lynne; Juric, Mario; Kaasalainen, Mikko; Styliani,; Kafka,; Kahn, Steven M; Kaib, Nathan A; Kalirai, Jason; Kantor, Jeff; Kasliwal, Mansi M; Keeton, Charles R; Kessler, Richard; Knezevic, Zoran; Kowalski, Adam; Krabbendam, Victor L; Krughoff, K Simon; Kulkarni, Shrinivas; Kuhlman, Stephen; Lacy, Mark; Lepine, Sebastien; Liang, Ming; Lien, Amy; Lira, Paulina; Long, Knox S; Lorenz, Suzanne; Lotz, Jennifer M; Lupton, R H; Lutz, Julie; Macri, Lucas M; Mahabal, Ashish A; Mandelbaum, Rachel; Marshall, Phil; May, Morgan; McGehee, Peregrine M; Meadows, Brian T; Meert, Alan; Milani, Andrea; Miller, Christopher J; Miller, Michelle; Mills, David; Minniti, Dante; Monet, David; Mukadam, Anjum S; Nakar, Ehud; Neill, Douglas R; Newman, Jeffrey A; Nikolaev, Sergei; Nordby, Martin; O'Connor, Paul; Oguri, Masamune; Oliver, John; Olivier, Scot S; Olsen, Julia K; Olsen, Knut; Olszewski, Edward W; Oluseyi, Hakeem; Padilla, Nelson D; Parker, Alex; Pepper, Joshua; Peterson, John R; Petry, Catherine; Pinto, Philip A; Pizagno, James L; Popescu, Bogdan; Prsa, Andrej; Radcka, Veljko; Raddick, M Jordan; Rasmussen, Andrew; Rau, Arne; Rho, Jeonghee; Rhoads, James E; Richards, Gordon T; Ridgway, Stephen T; Robertson, Brant E; Roskar, Rok; Saha, Abhijit; Sarajedini, Ata; Scannapieco, Evan; Schalk, Terry; Schindler, Rafe; Schmidt, Samuel; Schmidt, Sarah; Schneider, Donald P; Schumacher, German; Scranton, Ryan; Sebag, Jacques; Seppala, Lynn G; Shemmer, Ohad; Simon, Joshua D; Sivertz, M; Smith, Howard A; Smith, J Allyn; Smith, Nathan; Spitz, Anna H; Stanford, Adam; Stassun, Keivan G; Strader, Jay; Strauss, Michael A; Stubbs, Christopher W; Sweeney, Donald W; Szalay, Alex; Szkody, Paula; Takada, Masahiro; Thorman, Paul; Trilling, David E; Trimble, Virginia; Tyson, Anthony; Van Berg, Richard; Berk, Daniel Vanden; VanderPlas, Jake; Verde, Licia; Vrsnak, Bojan; Walkowicz, Lucianne M; Wandelt, Benjamin D; Wang, Sheng; Wang, Yun; Warner, Michael; Wechsler, Risa H; West, Andrew A; Wiecha, Oliver; Williams, Benjamin F; Willman, Beth; Wittman, David; Wolff, Sidney C; Wood-Vasey, W Michael; Wozniak, Przemek; Young, Patrick; Zentner, Andrew; Zhan, Hu

    2009-01-01

    A survey that can cover the sky in optical bands over wide fields to faint magnitudes with a fast cadence will enable many of the exciting science opportunities of the next decade. The Large Synoptic Survey Telescope (LSST) will have an effective aperture of 6.7 meters and an imaging camera with field of view of 9.6 deg^2, and will be devoted to a ten-year imaging survey over 20,000 deg^2 south of +15 deg. Each pointing will be imaged 2000 times with fifteen second exposures in six broad bands from 0.35 to 1.1 microns, to a total point-source depth of r~27.5. The LSST Science Book describes the basic parameters of the LSST hardware, software, and observing plans. The book discusses educational and outreach opportunities, then goes on to describe a broad range of science that LSST will revolutionize: mapping the inner and outer Solar System, stellar populations in the Milky Way and nearby galaxies, the structure of the Milky Way disk and halo and other objects in the Local Volume, transient and variable object...

  18. 基于DSpace的Lib 2.0%DSpace-based Lib 2.0

    Institute of Scientific and Technical Information of China (English)

    叶鹰; 黄晨

    2006-01-01

    指出用户互动是Web 2.0和Lib 2.0的典型特征,提出以开源软件系统DSpace作为数字图书馆核心引擎的Lib 2.0模型.综合资源、技术和服务管理讨论了基于DSpace构建Lib2.0的技术可能性和应用优越性,并论及与Lib 2.0相应的Librarian 2.0.

  19. Web 2.0感性

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    很多人都在问,什么是Web2.0,他本质的东西是什么。目前业界对Web 2.0在观点上达成一致的地方,主要集中在Web 2.0所具备的三个特定,第一个是分众效应,第二个是互动性,第三个是原创性。

  20. The 2-10 keV unabsorbed luminosity function of AGN from the XMM-Newton LSS, CDFS and COSMOS surveys

    CERN Document Server

    Ranalli, P; Georgantopoulos, I; Fotopoulou, S; Hsu, L -T; Salvato, M; Comastri, A; Pierre, M; Cappelluti, N; Carrera, F J; Chiappetti, L; Clerc, N; Gilli, R; Iwasawa, K; Pacaud, F; Paltani, S; Plionis, E; Vignali, C

    2015-01-01

    The XMM-LSS, XMM-COSMOS, and XMM-CDFS surveys are complementary in terms of sky coverage and depth. Together, they form a clean sample with the least possible variance in instrument effective areas and PSF. Therefore this is one of the best samples available to determine the 2-10 keV luminosity function of AGN and its evolution. The samples and the relevant corrections for incompleteness are described. A total of 2887 AGN is used to build the LF in the luminosity interval 10^42-10^46 erg/s, and in the redshift interval 0.001-4. A new method to correct for absorption by considering the probability distribution for the column density conditioned on the hardness ratio is presented. The binned luminosity function and its evolution is determined with a variant of the Page-Carrera method, improved to include corrections for absorption and to account for the full probability distribution of photometric redshifts. Parametric models, namely a double power-law with LADE or LDDE evolution, are explored using Bayesian in...

  1. Enhancement of keV X-rays from low-density cellulose triacetate (TAC) foam targets

    Science.gov (United States)

    Chaurasia, S.; Kaur, Channprit; Borisenko, N. G.; Pasley, J.; Orekhov, A.; Deo, M. N.

    2017-07-01

    The interaction of a high-power laser with a low-density foam target can in some instances result in a significant enhancement in x-ray generation relative to that when the same laser is incident upon a homogenous solid. In this paper, we present x-ray emission studies from foam targets where the density is varied from under-dense to over-dense. The targets are irradiated with the first harmonic of Nd:Glass laser. The laser intensity on the target was approximately 2 × 1014 W/cm2 with the pulse duration of 500 ps. Mass-matched cellulose triacetate foam targets with densities of 2 mg/cc, 4 mg/cc, 7 mg/cc, and 20 mg/cc were used. The areal density presented by the targets on the laser beam axis was held constant at 0.2 mg/cm2 by varying the target thickness in inverse proportion to the density. The x-ray yield in the spectral range (5-8 keV) and (4.5-16 keV) was found to be enhanced by approximately 2.3 times in foam targets with the density of 2 mg/cc (under-dense) compared with foam targets with the density of 20 mg/cc (over-dense).

  2. Institutions Struggling with Web 2.0

    NARCIS (Netherlands)

    Drachsler, Hendrik; Hermans, Henry

    2008-01-01

    Drachsler, H., & Hermans, H. (2008). Institutions Struggling with Web 2.0 - Moving Between Personal and Managed Learning Environments. Presentation at Online Educa 2008. December, 4, 2008, Berlin, Germany.

  3. Heading toward Artificial Intelligence 2.0

    Directory of Open Access Journals (Sweden)

    Yunhe Pan

    2016-12-01

    Full Text Available With the popularization of the Internet, permeation of sensor networks, emergence of big data, increase in size of the information community, and interlinking and fusion of data and information throughout human society, physical space, and cyberspace, the information environment related to the current development of artificial intelligence (AI has profoundly changed. AI faces important adjustments, and scientific foundations are confronted with new breakthroughs, as AI enters a new stage: AI 2.0. This paper briefly reviews the 60-year developmental history of AI, analyzes the external environment promoting the formation of AI 2.0 along with changes in goals, and describes both the beginning of the technology and the core idea behind AI 2.0 development. Furthermore, based on combined social demands and the information environment that exists in relation to Chinese development, suggestions on the development of AI 2.0 are given.

  4. Institutions Struggling with Web 2.0

    NARCIS (Netherlands)

    Drachsler, Hendrik; Hermans, Henry

    2008-01-01

    Drachsler, H., & Hermans, H. (2008). Institutions Struggling with Web 2.0 - Moving Between Personal and Managed Learning Environments. Presentation at Online Educa 2008. December, 4, 2008, Berlin, Germany.

  5. Checking Potassium origin of new emission line at 3.5 keV with K XIX line complex at 3.7 keV

    CERN Document Server

    Iakubovskyi, Dmytro

    2015-01-01

    Whether the new line at ~3.5 keV, recently detected in different samples of galaxy clusters, Andromeda galaxy and central part of our Galaxy, is due to Potassium emission lines, is now unclear. By using the latest astrophysical atomic emission line database AtomDB v. 3.0.2, we show that the most prospective method to directly check its Potassium origin will be the study of K XIX emission line complex at ~3.7 keV with future X-ray imaging spectrometers such as Soft X-ray spectometer on-board Astro-H mission or microcalorimeter on-board Micro-X sounding rocket experiment. To further reduce the remaining (factor ~3-5) uncertainty of the 3.7/3.5 keV ratio one should perform more precise modeling including removal of significant spatial inhomogeneities, detailed treatment of background components, and further extension of the modeled energy range.

  6. Early SPI/INTEGRAL measurements of galactic 511 keV line emission from positron annihilation

    OpenAIRE

    Jean, P.; Knoedlseder, J.; Lonjou, V.; Allain, M.; Roques, J. -P.; Skinner, G.K.; Teegarden, B.J.; Vedrenne, G.; von Ballmoos, P.; Cordier, B.; Caraveo, P.; Diehl, R.; Durouchoux, Ph.; Mandrou, P.; Matteson, J.

    2003-01-01

    We report the first measurements of the 511 keV line emission from the Galactic Centre (GC) region performed with the spectrometer SPI on the space observatory INTEGRAL (International Gamma-Ray Astrophysics Laboratory). Taking into account the range of spatial distribution models which are consistent with the data, we derive a flux of $9.9^{+4.7}_{-2.1} \\times 10^{-4}$ ph cm$^{-2}$ s$^{-1}$ and an intrinsic line width of $2.95^{+0.45}_{-0.51}$ keV (FWHM). The results are consistent with other...

  7. Networked Mediated Influence 2.0

    Science.gov (United States)

    2014-12-12

    information. To better compete with these new realities the PSYOP community will need to better educate themselves on how to effectively use Web 2.0...Web 2.0, New Media, Information Communicatioin Technologies, Psychological Theories, Social Networks, Digital Activism, Psychological Operations...the concept of “many-to-many” communication where traditional consumers of information are now also producers of information. To better compete with

  8. Ecodesign Directive version 2.0

    DEFF Research Database (Denmark)

    This present report reports on the main findings of the project Ecodesign Directive version 2.0 - from Energy Efficiency to Resource Efficiency. The project is financed by the Danish Environmental Protection Agency and ran from December 2012 to June 2014.......This present report reports on the main findings of the project Ecodesign Directive version 2.0 - from Energy Efficiency to Resource Efficiency. The project is financed by the Danish Environmental Protection Agency and ran from December 2012 to June 2014....

  9. Toxic Substances Control Act Test Submissions 2.0 (TSCATS 2.0)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Toxic Substances Control Act Test Submissions 2.0 (TSCATS 2.0) tracks the submissions of health and safety data submitted to the EPA either as required or...

  10. Characteristics of > 290 keV magnetosheath ions

    Directory of Open Access Journals (Sweden)

    A. Rigas

    Full Text Available We performed a statistical analysis of 290-500 keV ion data obtained by IMP-8 during the years 1982-1988 within the earth's magnetosheath and analysed in detail some time periods withdistinct ion bursts. These studies reveal the following characteristics for magnetosheath 290-500 keV energetic ions: (a the occurrence frequency and the flux of ions increase with increasing geomagnetic activity as indicated by the Kp index; the occurrence frequency was found to be as high as P > 42% for Kp > 2, (b the occurrence frequency in the dusk magnetosheath was found to be slightly dependent on the local time and ranged between ~30% and ~46% for all Kp values; the highest occurrence frequency was detected near the dusk magnetopause (21 LT, (c the high energy ion bursts display a dawn-dusk asymmetry in their maximum fluxes, with higher fluxes appearing in the dusk magnetosheath, and (d the observations in the dusk magnetosheath suggest that there exist intensity gradients of energetic ions from the bow shock toward the magnetopause. The statistical results are consistent with the concept that leakage of magnetospheric ions from the dusk magnetopause is a semi-permanent physical process often providing the magnetosheath with high energy (290-500 keV ions.Key words. Magnetospheric physics (magnetosheath; planetary magnetospheres. Space plasma physics (shock waves.

  11. 20 CFR 903.2 - Definitions.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Definitions. 903.2 Section 903.2 Employees' Benefits JOINT BOARD FOR THE ENROLLMENT OF ACTUARIES ACCESS TO RECORDS Records Pertaining to Individuals § 903.2 Definitions. (a) The term agency includes any executive department, military...

  12. 20 CFR 900.2 - Establishment.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Establishment. 900.2 Section 900.2 Employees' Benefits JOINT BOARD FOR THE ENROLLMENT OF ACTUARIES STATEMENT OF ORGANIZATION § 900.2 Establishment. The Joint Board has been established by the Secretary of Labor and the Secretary of the Treasury pursuant...

  13. 20 CFR 902.2 - Definitions.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Definitions. 902.2 Section 902.2 Employees' Benefits JOINT BOARD FOR THE ENROLLMENT OF ACTUARIES RULES REGARDING AVAILABILITY OF INFORMATION § 902.2 Definitions. (a) Records of the Joint Board. For purposes of this part, the term “records of the Joint...

  14. 20 CFR 703.2 - Forms.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Forms. 703.2 Section 703.2 Employees...' COMPENSATION ACT AND RELATED STATUTES INSURANCE REGULATIONS General § 703.2 Forms. (a) Any information required... OWCP district offices and on the Internet at http://www.dol.gov/esa/owcp/dlhwc/lsforms.htm....

  15. Definition of Health 2.0 and Medicine 2.0: a systematic review.

    NARCIS (Netherlands)

    Belt, T. van den; Engelen, L.J.; Berben, S.A.A.; Schoonhoven, L.J.

    2010-01-01

    BACKGROUND: During the last decade, the Internet has become increasingly popular and is now an important part of our daily life. When new "Web 2.0" technologies are used in health care, the terms "Health 2.0" or "Medicine 2.0" may be used. OBJECTIVE: The objective was to identify unique definitions

  16. Robotic Range Clearance Competition (R2C2)

    Science.gov (United States)

    2011-10-01

    Paddock. Meals—Breakfast, Lunch and Dinner will be available in the mess tent (See Schedule, Section 2.1). Snacks – Snack foods and bottled water...ROBOTIC RANGE CLEARANCE COMPETITION (R2C2) Final Report DISTRIBUTION A: AIR FORCE RESEARCH LABORATORY MATERIALS AND MANUFACTURING DIRECTORATE Air...other person or corporation; or convey any rights or permission to manufacture , use, or sell any patented invention that may relate to them. This

  17. The 2-79 keV X-ray spectrum of the circinus galaxy with NuSTAR, XMM-Newton, and Chandra: a fully compton-thick active galactic nucleus

    DEFF Research Database (Denmark)

    Arévalo, P.; Bauer, F. E.; Puccetti, S.;

    2014-01-01

    The Circinus galaxy is one of the closest obscured active galactic nuclei (AGNs), making it an ideal target for detailed study. Combining archival Chandra and XMM-Newton data with new NuSTAR observations, we model the 2-79 keV spectrum to constrain the primary AGN continuum and to derive physical...

  18. Definition of Health 2.0 and Medicine 2.0: A Systematic Review

    OpenAIRE

    Van De Belt, Tom H; Engelen, Lucien J.L.P.G.; Berben, Sivera A.A.; Schoonhoven, Lisette

    2010-01-01

    Background: During the last decade, the Internet has become increasingly popular and is now an important part of our daily life. When new “Web 2.0” technologies are used in health care, the terms “Health 2.0" or "Medicine 2.0” may be used.\\ud \\ud Objective: The objective was to identify unique definitions of Health 2.0/Medicine 2.0 and recurrent topics within the definitions.\\ud \\ud Methods: A systematic literature review of electronic databases (PubMed, Scopus, CINAHL) and gray literature on...

  19. Study on Web 2.0%浅议Web 2.0

    Institute of Scientific and Technical Information of China (English)

    周晓雨

    2010-01-01

    该文介绍了Web2.0的基本概念,Tim O'Reilly提出的规范定义Web2.0的七大准则以及Web2.0的技术,例如RSS,Mashup 和AJAX.与Web1.0相比,Web2.0提供了许多新功能.随着技术的发展,Web2.0技术被广泛应用,使用户获得更丰富的体验.

  20. Can Web 2.0 be Used Effectively Inside Organisations?

    Directory of Open Access Journals (Sweden)

    Alan Gilchrist

    2007-04-01

    Full Text Available There is a common conception amongst higher and middlemanagement that facilities that are “good for the Internet” can betransferred for application to the enterprise intranet. The latest fashion to arrive on the information scene is the Web 2.0 phenomenon, a range of tools including blogs, Wikis and RSS. This paper presents a brief overview of the Web 2.0 phenomenon and some tentative views on the relationship between Web 2.0 tools and the more formal and traditional tools used in information handling. The paper concludes that whereas Web 2.0 facilities will grow and develop on the Internet, the use of Web 2.0 facilities within the enterprise should be carefully planned as adjuncts to existing facilities, not as substitutes.

  1. Measurement of the Neutron-Proton and Neutron-Carbon Total Cross Section from 150 to 800 keV

    CERN Document Server

    Daub, B H; Kovash, M A; Matthews, J L; Miller, Z W; Shoniyozov, K; Yang, H

    2012-01-01

    There have been very few measurements of the total cross section for np scattering below 500 keV. In order to differentiate among NN potential models, improved cross section data between 20 and 600 keV are required. We measured the np and nC total cross sections in this energy region by transmission; a collimated neutron beam was passed through CH2 and C samples and transmitted neutrons were detected by a BC-501A liquid scintillator. Cross sections were obtained with a precision of 1.1-2.0% between 150 and 800 keV using ratios of normalized neutron yields measured with and without the scattering samples in the beam. In energy regions where they overlap, the present results are consistent with existing precision measurements, and fill in a significant gap in the data between En = 150 and 500 keV.

  2. Evaluation of the 1077keV gamma-ray emission probability from 68Ga decay

    CERN Document Server

    Huang, X L; Chen, X J; Chen, G C

    2013-01-01

    68Ga decays to the excited states of 68Zn through the electron capture decay mode. New recommended values for the emission probability of 1077keV gamma-ray given by the ENSDF and DDEP databases all use data from absolute measurements. In 2011 Jiang Liyang deduced a new value for 1077keV gamma-ray emission probability by measuring the 69Ga(n,2n)68Ga reaction cross section. The new value is about 20% lower than values obtained from previous absolute measurements and evaluations. In this paper, the discrepancies among the measurements and evaluations are analyzed carefully and the new values are re-recommended. Our recommended value for the emission probability of 1077keV gamma-ray is 2.72+-0.16 %.

  3. MENERAPKAN KONSEP PERPUSTAKAAN 2.0

    Directory of Open Access Journals (Sweden)

    Blasius Sudarsono

    2012-07-01

    Full Text Available The Library 2.0 terminology was coined in 2005 by Michael E Casey in his blog entitled Library Crunch. This article discusses the implementation of Library 2.0 concept, as a continuation of the previous article by the same author which had introduced the concept. Basically, Library 2.0 is an application of Web 2.0 for library purposes. It based on two fundament¬als that are: the strength of participation and the sophisticated of information technology. For library, theses forces based on three basic transformations i.e.: from book centered to human centered, from users oriented to users centered, and from information management to knowledge management. To discuss the implementation of the concept, the author did not start from the scratch, but looking other libraries that already had undertaken the effort. Examples are taken from USA, Australia, and China. Finally, the author discusses the possibility of Indonesian Librarians to implement the Library 2.0 concept. In addition the author also gives some suggestions.

  4. Web 2.0失败

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    “自以为自己在做Web 2.0的人,拿着商业计划书去找投资商的那群人,在我看来90%说的不是Web 2.0,这是第一个90%;第二个90%是,现在一腔热血立志要做Web2.0的人,他们之中90%的人没有做过,或是没有做好过Web1.0,我们看到一批热血青年,让我感觉自己仿佛回到了1999年;第三个90%是现在风险投资、实业投资投的所谓Web2.0的项目,90%是投错了。”和讯网CEO谢文很直白的讲述着他对国内Web 2.0现状的看法。

  5. 20 CFR 362.2 - Definitions.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Definitions. 362.2 Section 362.2 Employees' Benefits RAILROAD RETIREMENT BOARD INTERNAL ADMINISTRATION, POLICY AND PROCEDURES EMPLOYEES' PERSONAL... Civilian Employees' Claims Act of 1964, as amended (31 U.S.C. 240-243). (b) Article of extraordinary value...

  6. Can Web 2.0 be Used Effectively Inside Organisations?

    OpenAIRE

    Alan Gilchrist

    2007-01-01

    There is a common conception amongst higher and middle management that facilities that are “good for the Internet” can be transferred for application to the enterprise intranet. The latest fashion to arrive on the information scene is the Web 2.0 phenomenon, a range of tools including blogs, Wikis and RSS. This paper presents a brief overview of the Web 2.0 phenomenon and some tentative views on the relationship between Web 2.0 tools and the more formal and traditional tools used in informati...

  7. Peptide fragmentation by keV ion-induced dissociation

    NARCIS (Netherlands)

    Bari, S.; Hoekstra, R.A.; Schlathölter, T.A.

    2010-01-01

    We have studied multiple ionization and dissociation of a trapped protonated peptide (leucine enkephalin) as induced by keV singly and doubly charged ions (H(+), He(+,) (2+)) to demonstrate the potential of keV ions as a future tool for peptide identification. In contrast to conventional excitation

  8. Web 2.0 and pharmacy education.

    Science.gov (United States)

    Cain, Jeff; Fox, Brent I

    2009-11-12

    New types of social Internet applications (often referred to as Web 2.0) are becoming increasingly popular within higher education environments. Although developed primarily for entertainment and social communication within the general population, applications such as blogs, social video sites, and virtual worlds are being adopted by higher education institutions. These newer applications differ from standard Web sites in that they involve the users in creating and distributing information, hence effectively changing how the Web is used for knowledge generation and dispersion. Although Web 2.0 applications offer exciting new ways to teach, they should not be the core of instructional planning, but rather selected only after learning objectives and instructional strategies have been identified. This paper provides an overview of prominent Web 2.0 applications, explains how they are being used within education environments, and elaborates on some of the potential opportunities and challenges that these applications present.

  9. Efficient focusing of 8 keV X-rays with multilayer Fresnel zone plates fabricated by atomic layer deposition and focused ion beam milling.

    Science.gov (United States)

    Mayer, Marcel; Keskinbora, Kahraman; Grévent, Corinne; Szeghalmi, Adriana; Knez, Mato; Weigand, Markus; Snigirev, Anatoly; Snigireva, Irina; Schütz, Gisela

    2013-05-01

    Fresnel zone plates (FZPs) recently showed significant improvement by focusing soft X-rays down to ~10 nm. In contrast to soft X-rays, generally a very high aspect ratio FZP is needed for efficient focusing of hard X-rays. Therefore, FZPs had limited success in the hard X-ray range owing to difficulties of manufacturing high-aspect-ratio zone plates using conventional techniques. Here, employing a method of fabrication based on atomic layer deposition (ALD) and focused ion beam (FIB) milling, FZPs with very high aspect ratios were prepared. Such multilayer FZPs with outermost zone widths of 10 and 35 nm and aspect ratios of up to 243 were tested for their focusing properties at 8 keV and shown to focus hard X-rays efficiently. This success was enabled by the outstanding layer quality thanks to ALD. Via the use of FIB for slicing the multilayer structures, desired aspect ratios could be obtained by precisely controlling the thickness. Experimental diffraction efficiencies of multilayer FZPs fabricated via this combination reached up to 15.58% at 8 keV. In addition, scanning transmission X-ray microscopy experiments at 1.5 keV were carried out using one of the multilayer FZPs and resolved a 60 nm feature size. Finally, the prospective of different material combinations with various outermost zone widths at 8 and 17 keV is discussed in the light of the coupled wave theory and the thin-grating approximation. Al2O3/Ir is outlined as a promising future material candidate for extremely high resolution with a theoretical efficiency of more than 20% for as small an outermost zone width as 10 nm at 17 keV.

  10. WAITING FOR WEB 2.0

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    What will the next generation of Internet services mean for China? The Web 2.0 buzzword, having gathered speed in the United States in recent years as a way to describe new, more collaborative Internet applications, is attracting the attention and money of a batch of Chinese start-up firms. But will it attract the people? Late last year, the China Internet Society released a report that tracked this second major round of Internet boom. The findings of the report, titled China Web 2.0

  11. Web2.0 vs CIO

    Institute of Scientific and Technical Information of China (English)

    张述冠

    2006-01-01

    @@ 国外的一份调查表明,对于诸如Blog、Podcast、Wiki、RSS等Web2.0应用,CIO个人大多表示了浓厚的兴趣,并且已经身体力行.但有意思的是,该调查同时还发现,CIO们对于自己的企业引入Web2.0技术却兴趣索然.这一调查结果或许并不令人奇怪.

  12. Spatial distribution of upstream magnetospheric ≥50 keV ions

    Directory of Open Access Journals (Sweden)

    G. Kaliabetsos

    Full Text Available We present for the first time a statistical study of geq50 keV ion events of a magnetospheric origin upstream from Earth's bow shock. The statistical analysis of the 50-220 keV ion events observed by the IMP-8 spacecraft shows: (1 a dawn-dusk asymmetry in ion distributions, with most events and lower intensities upstream from the quasi-parallel pre-dawn side (4 LT-6 LT of the bow shock, (2 highest ion fluxes upstream from the nose/dusk side of the bow shock under an almost radial interplanetary magnetic field (IMF configuration, and (3 a positive correlation of the ion intensities with the solar wind speed and the index of geomagnetic index Kp, with an average solar wind speed as high as 620 km s-1 and values of the index Kp > 2. The statistical results are consistent with (1 preferential leakage of ~50 keV magnetospheric ions from the dusk magnetopause, (2 nearly scatter free motion of ~50 keV ions within the magnetosheath, and (3 final escape of magnetospheric ions from the quasi-parallel dawn side of the bow shock. An additional statistical analysis of higher energy (290-500 keV upstream ion events also shows a dawn-dusk asymmetry in the occurrence frequency of these events, with the occurrence frequency ranging between ~16%-~34% in the upstream region.Key words. Interplanetary physics (energetic particles; planetary bow shocks

  13. Becoming Teacher-Librarian 2.0

    Directory of Open Access Journals (Sweden)

    Anita Mary Brooks Kirkland

    2007-05-01

    Full Text Available This article discusses the place of Web 2.0 social software in the school library program. It examines the potential of this technology for enhancing teaching and learning, and the implications for students' information literacy. The article suggests ways for teacher-librarians to engage in professional learning to increase their knowledge of this evolving field.

  14. Do Web 2.0 Right

    Science.gov (United States)

    Light, Daniel

    2011-01-01

    The author and his colleague, Deborah Polin, traveled around the United States to get a first-hand look at how teachers are developing successful Web 2.0 activities for their classrooms. With funding from Intel, they interviewed 39 educators in 22 schools throughout the country about how they employed these tools in their classrooms in innovative…

  15. Change Management Meets Web 2.0

    Science.gov (United States)

    Gale, Doug

    2008-01-01

    Web 2.0 is the term used to describe a group of web-based creativity, information-sharing, and collaboration tools including wikis, blogs, social networks, and folksonomies. The common thread in all of these tools is twofold: They enable collaboration and information sharing, and their impact on higher education has been dramatic. A recent study…

  16. Integrated Pest Management 2.0

    NARCIS (Netherlands)

    Boonekamp, P.M.

    2013-01-01

    IPM 2.0 – Towards future-proof crop protection in Europe was een groot success. Het congres dat begin oktober 2012 in Wageningen werd gehouden was het tiende congres van de European Foundation for Plant Pathology (EFPP) en werd georganiseerd door de KNPV.

  17. The PLATO 2.0 mission

    NARCIS (Netherlands)

    Rauer, H.; et al., [Unknown; Hekker, S.

    2014-01-01

    PLATO 2.0 has recently been selected for ESA’s M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses fundamental questions such as: How do planetary systems form and evolve? Are there other systems with planets

  18. Web 2.0 (and Beyond)

    NARCIS (Netherlands)

    P.A. Arora (Payal)

    2015-01-01

    textabstractWeb 2.0 is a term coined to mark a new era of Internet usage driven by user interactivity and collaboration in generating content, moving away from the static information dissemination model associated with Web 1.0. It became common in early 2000 with the growth of social network sites,

  19. Web 2.0 (and Beyond)

    NARCIS (Netherlands)

    P.A. Arora (Payal)

    2015-01-01

    textabstractWeb 2.0 is a term coined to mark a new era of Internet usage driven by user interactivity and collaboration in generating content, moving away from the static information dissemination model associated with Web 1.0. It became common in early 2000 with the growth of social network sites,

  20. Web 2.0 and beyond

    NARCIS (Netherlands)

    P.A. Arora (Payal)

    2015-01-01

    markdownabstract__Abstract__ Web 2.0 is a term coined to mark a new era of Internet usage driven by user interactivity and collaboration in generating content, moving away from the static information dissemination model associated with Web 1.0. It became common in early 2000 with the growth of soci

  1. Change Management Meets Web 2.0

    Science.gov (United States)

    Gale, Doug

    2008-01-01

    Web 2.0 is the term used to describe a group of web-based creativity, information-sharing, and collaboration tools including wikis, blogs, social networks, and folksonomies. The common thread in all of these tools is twofold: They enable collaboration and information sharing, and their impact on higher education has been dramatic. A recent study…

  2. A Reflection on Web 2.0%Web 2.0的反思

    Institute of Scientific and Technical Information of China (English)

    匡文波

    2009-01-01

    该论文探讨了Web 2.0的价值,以及存在的问题.Web 2.0鼓励用户创造内容给网络舆论管理带来了更大的挑战,Web 2.0网站尚未找到成功的盈利模式,Web 2.0深受信息质量问题、安全问题、版权问题等困扰,而且Web 2.0网站的用户参与度其实很低.作者认为Web2.0并未改写网络传播业.

  3. Range distributions of /sup 11/B/sup +/ in Co, CoSi/sub 2/, Ti, and TiSi/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Delfino, M.; Morgan, A.E.; Maillot, P.; Broadbent, E.K.

    1988-07-15

    The range distributions of 10--120 keV /sup 11/B/sup +/ in polycrystalline Co, Ti, CoSi/sub 2/, and TiSi/sub 2/ targets have been measured by secondary ion mass spectrometry. The obtained projected ranges R/sub p/ and projected range stragglings ..delta..R/sub p/ are within 25% and 10%, respectively, of those predicted using the Monte Carlo computer program t-smcapsr-smcapsIm-smcaps. By comparison the one-dimensional Boltzmann transport calculation in Su-smcapsp-smcapsr-smcapsEm-smcaps-3 tends to overestimate R/sub p/ by as much as 300% at the highest ion energies.

  4. BioSense 2.0

    Science.gov (United States)

    Chester, Kelley G.

    2013-01-01

    Objective To familiarize public health practitioners with the BioSense 2.0 application and its use in all hazard surveillance. Introduction BioSense 2.0 protects the health of the American people by providing timely insight into the health of communities, regions, and the nation by offering a variety of features to improve data collection, standardization, storage, analysis, and collaboration. BioSense 2.0 is the result of a partnership between the Centers for Disease Control and Prevention (CDC) and the public health community to track the health and well-being of communities across the country. In 2010, the BioSense Program began a redesign effort to improve features such as centralized data mining and addressing concerns that the system could not meet its original objective to provide early warning or detect local outbreaks. Methods Using the latest technology, BioSense 2.0 integrates current health data shared by health departments from a variety of sources to provide insight on the health of communities and the country. By getting more information faster, local, state, and federal public health partners can detect and respond to more outbreaks and health events more quickly. From flu outbreaks to car accidents, BioSense 2.0 provides the critical data, information, and tools that public health officials need to better understand and address health problems at the local, state, regional, and national levels. Also, by knowing what is happening across local borders, public health professionals can anticipate potential health problems and respond effectively to protect the health of all people. The demonstration will include a basic overview of the BioSense 2.0 application and the functionality available to public health departments and their data providers. The presenter will also show an example of how BioSense 2.0 can be used in a real-world public health example. Conclusions Over the past two years much has been accomplished during the redesign effort. Bio

  5. 从Web 2.0映射到图书馆2.0

    Institute of Scientific and Technical Information of China (English)

    姜晓曦

    2006-01-01

    通过对Web.0的概念以及特点的介绍,引出图书馆2.0这一学术界讨论的新名词;并且将Web2.0的技术应用映射到图书馆2.0中展开论述,同时分析了图书馆2.0建设时面临的困难和发展前景.

  6. Quantifying sea surface temperature ranges of the Arabian Sea for the past 20 000 years

    Directory of Open Access Journals (Sweden)

    G. M. Ganssen

    2011-12-01

    Full Text Available The oxygen isotopic composition of planktonic foraminifera tests is one of the widest used geochemical tools to reconstruct past changes of physical parameters of the upper ocean. It is common practice to analyze multiple individuals from a mono-specific population and assume that the outcome reflects a mean value of the environmental conditions during calcification of the analyzed individuals. Here we present the oxygen isotope composition of individual specimens of the surface-dwelling species Globigerinoides ruber and Globigerina bulloides from sediment cores in the Western Arabian Sea off Somalia, inferred as indicators of past seasonal ranges in temperature. Combining the δ18O measurements of individual specimens to obtain temperature ranges with Mg/Ca based mean calcification temperatures allows us to reconstruct temperature extrema. Our results indicate that over the past 20 kyr the seasonal temperature range has fluctuated from its present value of 16 °C to mean values of 13 °C and 11 °C for the Holocene and LGM, respectively. The data for the LGM suggest that the maximum temperature was lower, whilst minimum temperature remained approximately constant. The rather minor variability in lowest summer temperatures during the LGM suggests roughly constant summer monsoon intensity, while upwelling-induced productivity was lowered.

  7. 50 CFR 30.2 - Disposition of surplus range animals.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Disposition of surplus range animals. 30.2... (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM RANGE AND FERAL ANIMAL MANAGEMENT Range Animals § 30.2 Disposition of surplus range animals. Disposition shall be made only during regularly scheduled...

  8. The 2-79 keV X-ray spectrum of the Circinus galaxy with NuSTAR, XMM-Newton, and Chandra: a fully Compton-thick active galactic nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Arévalo, P.; Bauer, F. E. [Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, 306, Santiago 22 (Chile); Puccetti, S. [ASDC-ASI, Via del Politecnico, I-00133 Roma (Italy); Walton, D. J.; Fuerst, F.; Grefenstette, B. W.; Harrison, F. A.; Madsen, K. K. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Koss, M. [Institute for Astronomy, Department of Physics, ETH Zurich, Wolfgang-Pauli-Strasse 27, CH-8093 Zurich (Switzerland); Boggs, S. E.; Craig, W. W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Brandt, W. N.; Luo, B. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Brightman, M. [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748, Garching bei München (Germany); Christensen, F. E. [Danish Technical University, Lyngby (Denmark); Comastri, A. [INAF-Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Gandhi, P. [Department of Physics, Durham University, South Road, Durham, DH1 3LE (United Kingdom); Hailey, C. J. [Columbia Astrophysics Laboratory and Department of Physics, Columbia University, 550 West 120th Street, New York, NY 10027 (United States); Madejski, G. [Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, Stanford University, 2575 Sand Hill Road M/S 29, Menlo Park, CA 94025 (United States); Marinucci, A. [Dipartimento di Matematica e Fisica, Università degli Studi Roma Tre, via della Vasca Navale 84, I-00146 Roma (Italy); and others

    2014-08-20

    The Circinus galaxy is one of the closest obscured active galactic nuclei (AGNs), making it an ideal target for detailed study. Combining archival Chandra and XMM-Newton data with new NuSTAR observations, we model the 2-79 keV spectrum to constrain the primary AGN continuum and to derive physical parameters for the obscuring material. Chandra's high angular resolution allows a separation of nuclear and off-nuclear galactic emission. In the off-nuclear diffuse emission, we find signatures of strong cold reflection, including high equivalent-width neutral Fe lines. This Compton-scattered off-nuclear emission amounts to 18% of the nuclear flux in the Fe line region, but becomes comparable to the nuclear emission above 30 keV. The new analysis no longer supports a prominent transmitted AGN component in the observed band. We find that the nuclear spectrum is consistent with Compton scattering by an optically thick torus, where the intrinsic spectrum is a power law of photon index Γ = 2.2-2.4, the torus has an equatorial column density of N {sub H} = (6-10) × 10{sup 24} cm{sup –2}, and the intrinsic AGN 2-10 keV luminosity is (2.3-5.1) × 10{sup 42} erg s{sup –1}. These values place Circinus along the same relations as unobscured AGNs in accretion rate versus Γ and L{sub X} versus L {sub IR} phase space. NuSTAR's high sensitivity and low background allow us to study the short timescale variability of Circinus at X-ray energies above 10 keV for the first time. The lack of detected variability favors a Compton-thick absorber, in line with the spectral fitting results.

  9. Bibliotecas escolares e web 2.0

    Directory of Open Access Journals (Sweden)

    Cassia Cordeiro Furtado

    2009-12-01

    Full Text Available O artigo enfoca o papel da educação e da biblioteca na Sociedade da Informação e apresenta conceitos e características da Biblioteca 2.0 (L2. Defende o uso da web 2.0, na biblioteca escolar, visando otimizar ou criar serviços e produtos, para fins de conquista dos usuários, visibilidade e espaço na escola e na sociedade. Identifica nos programas públicos de incentivo e implantação de bibliotecas nas escolas, no Brasil e em Portugal, a presença ou recomendações para o uso da web 2.0. Com base na literatura conclui que, em Portugal, já ocorre a iniciativa do uso dos blogs por parte da biblioteca escolar, porém com escassez de comentários por parte do usuário. E que as bibliotecas brasileiras têm um longo caminho a percorrer no que tange as bibliotecas escolares, como também no contexto dos sistemas de informação.

  10. Calculation of Multisphere Neutron Spectrometer Response Functions in Energy Range up to 20 MeV

    CERN Document Server

    Martinkovic, J

    2005-01-01

    Multisphere neutron spectrometer is a basic instrument of neutron measurements in the scattered radiation field at charged-particles accelerators for radiation protection and dosimetry purposes. The precise calculation of the spectrometer response functions is a necessary condition of the propriety of neutron spectra unfolding. The results of the response functions calculation for the JINR spectrometer with LiI(Eu) detector (a set of 6 homogeneous and 1 heterogeneous moderators, "bare" detector within cadmium cover and without it) at two geometries of the spectrometer irradiation - in uniform monodirectional and uniform isotropic neutron fields - are given. The calculation was carried out by the code MCNP in the neutron energy range 10$^{-8}$-20 MeV.

  11. Spøgelseshistorier 2.0

    DEFF Research Database (Denmark)

    Hansen, Kim Toft

    2012-01-01

    Jeg læser Arne Dahls miniroman Ghost House 2.0 som et eftertrykkeligt udråbstegn, der understreger den holdning til metafysik, som Arne Dahls bøger om A-gruppen signalerer. Den samlede krimiserie inddrager gennemgående en diskussion af metafysiske rammer, men viser samtidig en refleksiv distance...... dertil. Det er denne lokkelse såvel som distance, Dahl arbejder med i Ghost House 2.0. Ydermere bruger Arne Dahl i dette tilfælde metafiktionen som et kritisk element, hvilket skaber et særligt forhold mellem metafysik og metafiktion. Fortællingen handler i dette tilfælde dog ikke om A-gruppen. Jeg...

  12. The $(2,0)$ superconformal bootstrap

    CERN Document Server

    Beem, Christopher; Rastelli, Leonardo; van Rees, Balt C

    2016-01-01

    We develop the conformal bootstrap program for six-dimensional conformal field theories with $(2,0)$ supersymmetry, focusing on the universal four-point function of stress tensor multiplets. We review the solution of the superconformal Ward identities and describe the superconformal block decomposition of this correlator. We apply numerical bootstrap techniques to derive bounds on OPE coefficients and scaling dimensions from the constraints of crossing symmetry and unitarity. We also derive analytic results for the large spin spectrum using the lightcone expansion of the crossing equation. Our principal result is strong evidence that the $A_1$ theory realizes the minimal allowed central charge $(c=25)$ for any interacting $(2,0)$ theory. This implies that the full stress tensor four-point function of the $A_1$ theory is the unique unitary solution to the crossing symmetry equation at $c=25$. For this theory, we estimate the scaling dimensions of the lightest unprotected operators appearing in the stress tenso...

  13. EcoMark 2.0

    DEFF Research Database (Denmark)

    Guo, Chenjuan; Yang, Bin; Andersen, Ove;

    2015-01-01

    Eco-routing is a simple yet effective approach to substantially reducing the environmental impact, e.g., fuel consumption and greenhouse gas (GHG) emissions, of vehicular transportation. Eco-routing relies on the ability to reliably quantify the environmental impact of vehicles as they travel...... in a spatial network. The procedure of quantifying such vehicular impact for road segments of a spatial network is called eco-weight assignment. EcoMark 2.0 proposes a general framework for eco-weight assignment to enable eco-routing. It studies the abilities of six instantaneous and five aggregated models......, and experiments for assessing the utility of the impact models in assigning eco-weights. The application of EcoMark 2.0 indicates that the instantaneous model EMIT and the aggregated model SIDRA-Running are suitable for assigning eco-weights under varying circumstances. In contrast, other instantaneous models...

  14. Web 2.0烧钱

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    在中国,但凡参加一次有关Web 2.0的研讨会,你首先要做出两种选择:一个是带足100张名片,因为那里有太多的网络精英,有太多新的面孔。另一个选择是你可以一张名片都不带,因为那里有太多的空想者,“凭借一个想法,就想融到百万美元投资的人比比皆是”。Web 2.0的聚会有时候对于创业者来说更像一场幻梦。

  15. Zyncro: the intranet 2.0

    OpenAIRE

    Grau, Francesc; Xifra, Jordi

    2011-01-01

    Zyncro opens a new dimension in corporate documentation management, based on the well-known concept of intranets and adapting it to the new 2.0 culture of collaboration and work online. Internal communications in public and private organizations are alive, and their flows of interaction between internal and external members of the organization are becoming more intense. Tools capable of handling large volumes of information in an easy, fast and secure manner are needed. This is where Zyncro a...

  16. Heliospheric Neutral Atom Spectra Between 0.01 and 6 keV fom IBEX

    Science.gov (United States)

    Fuselier, S. A.; Allegrini, F.; Bzowski, M.; Funsten, H. O.; Ghielmetti, A. G.; Gloeckler, G.; Heirtzler, D.; Janzen, P.; Kubiak, M.; Kucharek, H.; McComas, D. J.; Moebius, E.; Moore, T. E.; Petrinec, S. M.; Quinn, M.; Reisenfeld, D.; Saul, L. A.; Scheer, J. A.; Schwardron, N.; Trattner, K. J.; Vanderspek, R.; Wurz, P.

    2012-01-01

    Since 2008 December, the Interstellar Boundary Explorer (IBEX) has been making detailed observations of neutrals from the boundaries of the heliosphere using two neutral atom cameras with overlapping energy ranges. The unexpected, yet defining feature discovered by IBEX is a Ribbon that extends over the energy range from about 0.2 to 6 keV. This Ribbon is superposed on a more uniform, globally distributed heliospheric neutral population. With some important exceptions, the focus of early IBEX studies has been on neutral atoms with energies greater than approx. 0.5 keV. With nearly three years of science observations, enough low-energy neutral atom measurements have been accumulated to extend IBEX observations to energies less than approx. 0.5 keV. Using the energy overlap of the sensors to identify and remove backgrounds, energy spectra over the entire IBEX energy range are produced. However, contributions by interstellar neutrals to the energy spectrum below 0.2 keV may not be completely removed. Compared with spectra at higher energies, neutral atom spectra at lower energies do not vary much from location to location in the sky, including in the direction of the IBEX Ribbon. Neutral fluxes are used to show that low energy ions contribute approximately the same thermal pressure as higher energy ions in the heliosheath. However, contributions to the dynamic pressure are very high unless there is, for example, turbulence in the heliosheath with fluctuations of the order of 50-100 km/s.

  17. Health 2.0 and Medicine 2.0: tensions and controversies in the field.

    Science.gov (United States)

    Hughes, Benjamin; Joshi, Indra; Wareham, Jonathan

    2008-08-06

    The term Web 2.0 became popular following the O'Reilly Media Web 2.0 conference in 2004; however, there are difficulties in its application to health and medicine. Principally, the definition published by O'Reilly is criticized for being too amorphous, where other authors claim that Web 2.0 does not really exist. Despite this skepticism, the online community using Web 2.0 tools for health continues to grow, and the term Medicine 2.0 has entered popular nomenclature. This paper aims to establish a clear definition for Medicine 2.0 and delineate literature that is specific to the field. In addition, we propose a framework for categorizing the existing Medicine 2.0 literature and identify key research themes, underdeveloped research areas, as well as the underlying tensions or controversies in Medicine 2.0's diverse interest groups. In the first phase, we employ a thematic analysis of online definitions, that is, the most important linked papers, websites, or blogs in the Medicine 2.0 community itself. In a second phase, this definition is then applied across a series of academic papers to review Medicine 2.0's core literature base, delineating it from a wider concept of eHealth. The terms Medicine 2.0 and Health 2.0 were found to be very similar and subsume five major salient themes: (1) the participants involved (doctors, patients, etc); (2) its impact on both traditional and collaborative practices in medicine; (3) its ability to provide personalized health care; (4) its ability to promote ongoing medical education; and (5) its associated method- and tool-related issues, such as potential inaccuracy in enduser-generated content. In comparing definitions of Medicine 2.0 to eHealth, key distinctions are made by the collaborative nature of Medicine 2.0 and its emphasis on personalized health care. However, other elements such as health or medical education remain common for both categories. In addition, this emphasis on personalized health care is not a salient theme

  18. Kinetic energies of charged fragments resulting from multifragmentation and asymmetric fission of the C{sub 60} molecule in collisions with monocharged ions (2-130 keV)

    Energy Technology Data Exchange (ETDEWEB)

    Rentenier, A; Bordenave-Montesquieu, D; Moretto-Capelle, P; Bordenave-Montesquieu, A [Laboratoire CAR-IRSAMC, UMR 5589 CNRS - Universite Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse Cedex (France)

    2003-04-28

    Multifragmentation and asymmetric fission (AF) of the C{sub 60} molecule induced by H{sup +}, H{sub 2}{sup +}, H{sub 3}{sup +} and He{sup +} ions at medium collision energies (2-130 keV) are considered. Momenta and kinetic energies of C{sub n}{sup +} fragment ions (n = 1- 12) are deduced from an analysis of time-of-flight spectra. In multifragmentation processes, momenta are found to be approximately constant when n > 2, a behaviour which explains that the most probable kinetic energy, as well as the width of the kinetic energy distributions, is found to be inversely proportional to the fragment size n; both momenta and kinetic energies are independent of the velocity and nature of the projectile, and hence of the energy deposit. A specific study of the AF shows that the kinetic energies of C{sub 2}{sup +}, C{sub 4}{sup +} and C{sub 6}{sup +} fragments are also independent of the collision velocity and projectile species; a quantitative agreement is found with values deduced from kinetic energy release measurements by another group in electron impact experiments, and the observed decrease when the mass of the light fragment increases is also reproduced. A quantitative comparison of AF and multifragmentation for the n = 2, 4 and 6 fragment ions shows that kinetic energies in AF exceed that in multifragmentation, a result which explains the oscillations observed when momenta or kinetic energies of fragments are plotted against the n-value. The AF yield is also found to scale with the energy deposit in the collision velocity range extending below the velocity at the maximum of the electronic stopping power; except for protons, it remains negligible with respect to multifragmentation as soon as the total energy deposit exceeds about 100 eV.

  19. Measurement of multilayer reflectivities from 8 keV to 130 keV

    DEFF Research Database (Denmark)

    Hoeghoej, P.; Joensen, K. D.; Christensen, Finn Erland

    1993-01-01

    This paper presents measurements of specular and non-specular reflectivities of a W/Si multilayer with period d=135.1 A. Angular dispersive measurements were performed at 8.05 keY and 59.3 keY, while energy dispersive measurements were made in the range of 17 keV to 130 keY. At an incidence angle...

  20. LSST Science Book, Version 2.0

    OpenAIRE

    LSST Science Collaboration; Abell, Paul A.; Allison, Julius; Anderson, Scott F.; Andrew, John R.; Angel, J. Roger P.; Armus, Lee; Arnett, David; Asztalos, S. J.; Axelrod, Tim S.; Bailey, Stephen; Ballantyne, D. R.; Bankert, Justin R.; Barkhouse, Wayne A.; Barr, Jeffrey D.

    2009-01-01

    A survey that can cover the sky in optical bands over wide fields to faint magnitudes with a fast cadence will enable many of the exciting science opportunities of the next decade. The Large Synoptic Survey Telescope (LSST) will have an effective aperture of 6.7 meters and an imaging camera with field of view of 9.6 deg^2, and will be devoted to a ten-year imaging survey over 20,000 deg^2 south of +15 deg. Each pointing will be imaged 2000 times with fifteen second exposures in six broad band...

  1. Lunar Laser Ranging Experiment for Japanese SELENE-2 landing mission

    Science.gov (United States)

    Noda, H.; Kunimori, H.; Araki, H.; Fuse, T.; Hanada, H.; Katayama, M.; Otsubo, T.; Sasaki, S.; Tazawa, S.; Tsuruta, S.; Funazaki, K.; Taniguchi, H.; Murata, K.

    2012-04-01

    We present the development status of the Lunar Laser Ranging experiment proposed to Japanese SELENE-2 lunar landing mission. The Lunar Laser Ranging measures the distance between laser link stations on the Earth and retroreflectors on the Moon, by detecting the time of flight of photons of high-powered laser emitted from the ground station. Since the Earth-Moon distance contains information of lunar orbit, lunar solid tides, and lunar orientation and rotation, we can estimate the inner structure of the Moon through orientation, rotation and tide. Retroreflectors put by the Apollo and Luna missions in 1970's are arrays of many small Corner Cube Prisms (CCP). Because of the tilt of these arrays from the Earth direction due to the optical libration, the returned laser pulse is broaden, causing the main range error of more than 1.5 cm ([1]). Therefore retroreflectors with larger single aperture are necessary for more accurate ranging, and we propose a large single retroreflector of hollow-type with 15 cm aperture. Larger aperture up to 20 cm might be favorable if more mass is permitted for payloads. To cancel the velocity aberration, a large, single aperture retroreflector needs small amount of offset angle between the reflecting planes to spoil the return beam pattern. This angle offset, called Dihedral Angle Offset (DAO) must be optimized to be less than 1 second of arc with 0.1 seconds of arc accuracy to accumulate more photons [2, 3]. The realization of such small DAO is challenging with current technology, therefore the development of fabrication method is important. As for the mirror material, some ceramic products (ZPF: Zero-expansion Pore-free ceramics or SiC: silicon carbide) are under consideration in terms of weight, hardness and handling. The thermal quality of the material can be evaluated by both the thermal conductivity and the coefficient of thermal expansion. The method to fasten three planes each other with precise DAO must be developed.

  2. Library 2.0 Theory: Web 2.0 and Its Implications for Libraries

    Directory of Open Access Journals (Sweden)

    Jack M. Maness

    2006-06-01

    Full Text Available This article posits a definition and theory for "Library 2.0". It suggests that recent thinking describing the changing Web as "Web 2.0" will have substantial implications for libraries, and recognizes that while these implications keep very close to the history and mission of libraries, they still necessitate a new paradigm for librarianship. The paper applies the theory and definition to the practice of librarianship, specifically addressing how Web 2.0 technologies such as synchronous messaging and streaming media, blogs, wikis, social networks, tagging, RSS feeds, and mashups might intimate changes in how libraries provide access to their collections and user support for that access.

  3. FEI Tecnai G2 F20

    Directory of Open Access Journals (Sweden)

    Martina Luysberg

    2016-06-01

    Full Text Available The FEI Titan Tecnai G2 F20 is a versatile transmission electron microscope which is equipped with a Gatan Tridiem 863P post column image filter (GIF and a high angle energy dispersive X-ray (EDX detector. This set up allows for a variety of experiments such as conventional imaging and diffraction, recording of bright- and dark-field scanning transmission electron microscopy (STEM images, or acquiring elemental maps extracted from energy electron loss spectra (EELS or EDX signals.

  4. UQTk version 2.0 user manual.

    Energy Technology Data Exchange (ETDEWEB)

    Debusschere, Bert J.; Sargsyan, Khachik; Safta, Cosmin

    2013-10-01

    The UQ Toolkit (UQTk) is a collection of libraries and tools for the quanti cation of uncer- tainty in numerical model predictions. Version 2.0 o ers intrusive and non-intrusive methods for propagating input uncertainties through computational models, tools for sensitivity anal- ysis, methods for sparse surrogate construction, and Bayesian inference tools for inferring parameters from experimental data. This manual discusses the download and installation process for UQTk, provides pointers to the UQ methods used in the toolkit, and describes some of the examples provided with the toolkit.

  5. 来吧!WEB 2.0

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ 互联网从不缺少慨念和焦点,从木子美到芙蓉姐姐都在网上掀起不大不小的风波,但这次风暴的中心却是互联网本身,是互联网未来的发展方向,卷入的人群远非"粉丝"那么简单,而是一些互联网的精英们,在这场风暴中一个新的名词进入我们的视线:Web 2.0.

  6. Teaching PBL with Web 2.0

    DEFF Research Database (Denmark)

    Dohn, Nina Bonderup; Buus, Lillian

    2013-01-01

    Web 2.0-mediated learning activities are associated with a number of potentials for learning. Among these potentials are pedagogical advantages connected with bottom-up user-generation of content; opportunities for organizing flexible learning; and possibilities of supporting the development......, the teacher of the BA-level problem-based learning course, sighed as he read through the Facebook postings entered by his students during the last 10 hours. Where were the theoretical questions and methodological issues he had been expecting? Once again, the students had posted links to YouTube videos...

  7. Compton polarimetry detection of small circularly and linearly polarized impurities in Mössbauer 8.4 keV (3/2-1/2) M1 γ-transition of 169Tm

    Science.gov (United States)

    Tsinoev, V.; Cherepanov, V.; Shuvalov, V.; Balysh, A.; Gabbasov, R.

    2016-12-01

    The arrangement of an experiment to detect the P-odd and P, T-odd polarized part of the Mössbauer (+3/2- +1/2) gamma transition of a deformed 169Tm nucleus with an energy of 8.4 keV by Compton polarimetry is discussed. Tm 2O3 single crystal with a quadrupolarly split Mössbauer spectrum is proposed as a resonance polarizer. A Be-scatterer-based Compton polarimeter and a synchronously detecting system will be used to measure the P-odd circular polarization P C and P, T-odd linear polarization P L .The expected accuracy of measuring the relative magnitude of the P, T-odd contribution is about 1% of the magnitude of usual weak nucleon-nucleon interaction.

  8. Compton polarimetry detection of small circularly and linearly polarized impurities in Mössbauer 8.4 keV (3/2-1/2) M1 γ-transition of {sup 169}Tm

    Energy Technology Data Exchange (ETDEWEB)

    Tsinoev, V.; Cherepanov, V.; Shuvalov, V.; Balysh, A.; Gabbasov, R., E-mail: graul@list.ru [National Research Centre “Kurchatov Institute” (Russian Federation)

    2016-12-15

    The arrangement of an experiment to detect the P−odd and P, T−odd polarized part of the Mössbauer ({sup +}3/2– {sup +}1/2) gamma transition of a deformed {sup 169}Tm nucleus with an energy of 8.4 keV by Compton polarimetry is discussed. Tm {sub 2}O{sub 3} single crystal with a quadrupolarly split Mössbauer spectrum is proposed as a resonance polarizer. A Be-scatterer-based Compton polarimeter and a synchronously detecting system will be used to measure the P-odd circular polarization P{sub C}and P, T-odd linear polarization P{sub L}.The expected accuracy of measuring the relative magnitude of the P, T-odd contribution is about 1% of the magnitude of usual weak nucleon–nucleon interaction.

  9. [Gastroenterology 2.0: useful resources for the gastroenterologist available on the Web 2.0].

    Science.gov (United States)

    Curioso, Walter H; Proaño, Alvaro; Ruiz, Eloy F

    2011-01-01

    The term Web 2.0 refers to the use of Internet applications which enable the users to share, participate and collaborate together on information. The objective of this study is to check different applications that use Web 2.0, which could help the gastroenterologist in his daily practice. The applications that will be checked include: blogs, microblogging, RSS, podcasts, wikis and social networks. "Gastroenterology 2.0" represents the applications, services, and tools based on Web 2.0, which are of easy use and easily accessible - to consumers, patients, gastroenterologists and other health professionals, as well as researchers. Although several studies have shown the benefits these technologies have on the medical practice, it is necessary to conduct further studies to demonstrate the use of these applications on improving health.

  10. Bringing Web 2.0 to bioinformatics.

    Science.gov (United States)

    Zhang, Zhang; Cheung, Kei-Hoi; Townsend, Jeffrey P

    2009-01-01

    Enabling deft data integration from numerous, voluminous and heterogeneous data sources is a major bioinformatic challenge. Several approaches have been proposed to address this challenge, including data warehousing and federated databasing. Yet despite the rise of these approaches, integration of data from multiple sources remains problematic and toilsome. These two approaches follow a user-to-computer communication model for data exchange, and do not facilitate a broader concept of data sharing or collaboration among users. In this report, we discuss the potential of Web 2.0 technologies to transcend this model and enhance bioinformatics research. We propose a Web 2.0-based Scientific Social Community (SSC) model for the implementation of these technologies. By establishing a social, collective and collaborative platform for data creation, sharing and integration, we promote a web services-based pipeline featuring web services for computer-to-computer data exchange as users add value. This pipeline aims to simplify data integration and creation, to realize automatic analysis, and to facilitate reuse and sharing of data. SSC can foster collaboration and harness collective intelligence to create and discover new knowledge. In addition to its research potential, we also describe its potential role as an e-learning platform in education. We discuss lessons from information technology, predict the next generation of Web (Web 3.0), and describe its potential impact on the future of bioinformatics studies.

  11. Clusterix 2.0 for Gaia

    Science.gov (United States)

    Balaguer-Núez, L.; Galadí-Enríquez, D.; López del Fresno, M.; Solano, E.; Jordi, C.; Sézima, T.; Paunzen, E.

    2017-03-01

    We present an advanced, VO-compliant version of Clusterix, a tool for the determination of membership probabilities in stellar clusters from proper motion data. Clusterix is a web-based, interactive application that allows the computation of membership probabilities from proper motions through a fully non-parametric method. Version 1.0 (http://clusterix.cerit-sc.cz/) was developed as a collaboration between the Masaryk University (Czech Republic) and the Universitat de Barcelona (Spain), as a complement to the WEBDA (http://webda.physics.muni.cz) database of observational data on stars in open clusters. Clusterix 2.0 (http://clusterix.cab.inta-csic.es/clusterix/) is oriented towards the exploitation of Gaia data products. With the participation of the Spanish Virtual Observatory, Clusterix now features an improved user interface for a faster, easier and more accurate interactive definition of the cluster and field proper motion distributions. The system provides fast feedback between membership probability determinations and the distribution of observables for the most probable members and field stars, with graphic tools to display, for instance, photometric diagrams on the fly. Furthermore, Clusterix 2.0 is fully VO-compatible, what opens interesting prospects for the astrophysical exploitation of the improved membership probabilities that will be capable to provide for many open clusters observed by Gaia.

  12. Web 2.0 and competitiveness improvement

    Directory of Open Access Journals (Sweden)

    Bauerová, Danuše

    2011-12-01

    Full Text Available Article shows implementation of A Model of Learning Powered by Technology at university environment. A Positive Digital Identity development on Web2.0 cloud is presented. People are creating their own portfolios - Personal Learning Portfolio and Personal Credit Portfolio. The part of it such proposals are generalizing methodologies to be useful to improve competitiveness of students, pedagogues, scientists but also institutions as well as anybody of lifelong learning activities.

    Este artículo muestra la puesta en marcha de un modelo de aprendizaje potenciado por la tecnología en el entorno de la Universidad. Se presenta un desarrollo de la Identidad Digital Positiva sobre la nube Web2.0. Las personas crean sus propios portafolios –Personal Learning Portfolio y Personal Credit Portfolio. Por otra parte, estas propuestas representan la generalización de metodologías que son útiles para mejorar la competitividad de estudiantes, pedagogos, científicos, pero también de las instituciones, así como de las actividades de aprendizaje a lo largo de la vida.

  13. Measurements of electron detachment cross sections in 10-50 keV impact energy H{sup {minus}} + collisions

    Energy Technology Data Exchange (ETDEWEB)

    Seely, D.G. [Albion College, MI (United States); Sen, A.; Kvale, T.J. [Univ. of Toledo, OH (United States)

    1996-05-01

    Absolute cross sections for the single- and double-electron detachment ({sigma}{sub {minus}10} and {sigma}{sub {minus}11}, respectively) in collisions between H{sup {minus}} and methane have been measured in the energy range of 10-50 keV. A well-collimated H{sup {minus}} ion beam was accelerated into a gas target cell containing methane and the scattered H{sup {minus},0,+} beam components of the collision products were magnetically separated and simultaneously measured by separate detectors. The cross sections were determined by quadratic least squares fits of the scattered-beam growth curves. In the present energy region, {sigma}{sub {minus}10} exhibits a maximum at around 20 keV impact energy and then monotonically decreases with increasing impact energy. However, {sigma}{sub {minus}11} displays a different energy dependence by monotonically increasing with increasing impact energy until about 25 keV and thereafter remaining relatively constant.

  14. Sampling Number Effects in 2D and Range Imaging of Range-gated Acquisition

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Seong-Ouk; Park, Seung-Kyu; Baik, Sung-Hoon; Cho, Jai-Wan; Jeong, Kyung-Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this paper, we analyzed the number effects of sampling images for making a 2D image and a range image from acquired RGI images. We analyzed the number effects of RGI images for making a 2D image and a range image using a RGI vision system. As the results, 2D image quality was not much depended on the number of sampling images but on how much well extract efficient RGI images. But, the number of RGI images was important for making a range image because range image quality was proportional to the number of RGI images. Image acquiring in a monitoring area of nuclear industry is an important function for safety inspection and preparing appropriate control plans. To overcome the non-visualization problem caused by airborne obstacle particles, vision systems should have extra-functions, such as active illumination lightening through disturbance airborne particles. One of these powerful active vision systems is a range-gated imaging system. The vision system based on the range-gated imaging system can acquire image data from raining or smoking environments. Range-gated imaging (RGI) is a direct active visualization technique using a highly sensitive image sensor and a high intensity illuminant. Currently, the range-gated imaging technique providing 2D and 3D images is one of emerging active vision technologies. The range-gated imaging system gets vision information by summing time sliced vision images. In the RGI system, a high intensity illuminant illuminates for ultra-short time and a highly sensitive image sensor is gated by ultra-short exposure time to only get the illumination light. Here, the illuminant illuminates objects by flashing strong light through airborne disturbance particles. Thus, in contrast to passive conventional vision systems, the RGI active vision technology robust for low-visibility environments.

  15. On the Emission of Electrons from Solid H_2 and D_2 by Bombardment with 1-3 keV Electrons up to Very Large Angles of Incidence

    DEFF Research Database (Denmark)

    Schou, Jørgen; Sørensen, H.

    1982-01-01

    Electron emission, i.e. electron reflection (ER) and secondary electron emission (SEE), was studied for solid H2 and D2 for oblique incidence of 1-3 keV electrons up to an angle of incidence θ of 83°. The ER coefficient η was small at low angles, and rose rapidly with increasing θ above 60...... at the largest angles. The results agree well with the existing qualitative tendencies described in the literature. The variation with the angle of incidence shows a fair agreement with an estimate based on data for the angular distribution of electrons ejected from ionized hydrogen molecules. In addition......, an ionization cascade treatment leads to an expression for the behavior of the yield of those secondary electrons that are generated directly by the primaries. The agreement with experimental data is good...

  16. IntelliGrow 2.0

    DEFF Research Database (Denmark)

    Markvart, Jakob; Aaslyng, Jesper Peter Mazanti; Kalita, Sebastian

    2008-01-01

    . A special emphasis will be on components that utilize local weather predictions for energy saving purposes and timing of production as well as components with photosynthesis based strategies for use of artificial light. We expect that the extension of intelligent climate control will result in better......Since 1996 a dynamic model based climate control concept (IntelliGrow) has been developed in Denmark. The aim of the system is to adjust the greenhouse climate dynamic, so that the natural resources are used as optimal as possible. The concept has been proved to work in both growth chamber...... and greenhouse experiments, with many different species of pot plants, resulting in energy savings up to 40%, depending on the outside climate. Based on the former work a new system (IntelliGrow 2.0) is being developed which offers an improved user interface and an extensible component model. The goal is to test...

  17. Mass spectrometry and Web 2.0.

    Science.gov (United States)

    Murray, Kermit K

    2007-10-01

    The term Web 2.0 is a convenient shorthand for a new era in the Internet in which users themselves are both generating and modifying existing web content. Several types of tools can be used. With social bookmarking, users assign a keyword to a web resource and the collection of the keyword 'tags' from multiple users form the classification of these resources. Blogs are a form of diary or news report published on the web in reverse chronological order and are a popular form of information sharing. A wiki is a website that can be edited using a web browser and can be used for collaborative creation of information on the site. This article is a tutorial that describes how these new ways of creating, modifying, and sharing information on the Web are being used for on-line mass spectrometry resources.

  18. FLEXAN (version 2.0) user's guide

    Science.gov (United States)

    Stallcup, Scott S.

    1989-01-01

    The FLEXAN (Flexible Animation) computer program, Version 2.0 is described. FLEXAN animates 3-D wireframe structural dynamics on the Evans and Sutherland PS300 graphics workstation with a VAX/VMS host computer. Animation options include: unconstrained vibrational modes, mode time histories (multiple modes), delta time histories (modal and/or nonmodal deformations), color time histories (elements of the structure change colors through time), and rotational time histories (parts of the structure rotate through time). Concurrent color, mode, delta, and rotation, time history animations are supported. FLEXAN does not model structures or calculate the dynamics of structures; it only animates data from other computer programs. FLEXAN was developed to aid in the study of the structural dynamics of spacecraft.

  19. e-Catalunya 2.0

    OpenAIRE

    López Muñoz, Jessica

    2010-01-01

    Este PFC consiste en el diseño e implementación de la versión 2.0 del proyecto e-Catalunya. Esta versión consiste en un cambio, ya que, ahora se tratará toda la información introducida por el usuario desde un único punto. Inicialmente se gestionaba de una manera descentralizada. e-Catalunya surgió como un proyecto destinado a mejorar las relaciones entre profesionales de la administración pública, el problema es que fue hace 6 años. Con esta versión se intenta acercar más estas relaciones ent...

  20. Irradiation damage in aluminium single crystals produced by 50-keV aluminium and copper ions

    DEFF Research Database (Denmark)

    Henriksen, L.; Johansen, A.; Koch, J.

    1968-01-01

    Aluminium single crystals, thin enough to be examined by electron microscopy, have been irradiated with 50-keV aluminium and copper ions. The irradiation fluxes were in the range 1011–1014 cm−2 s−1 and the doses were from 6 × 1012 to 6 × 1014 cm−2. Irradiation along either a or a direction produc...

  1. BSD Portals for LINUX 2.0

    Science.gov (United States)

    McNab, A. David; woo, Alex (Technical Monitor)

    1999-01-01

    Portals, an experimental feature of 4.4BSD, extend the file system name space by exporting certain open () requests to a user-space daemon. A portal daemon is mounted into the file name space as if it were a standard file system. When the kernel resolves a pathname and encounters a portal mount point, the remainder of the path is passed to the portal daemon. Depending on the portal "pathname" and the daemon's configuration, some type of open (2) is performed. The resulting file descriptor is passed back to the kernel which eventually returns it to the user, to whom it appears that a "normal" open has occurred. A proxy portalfs file system is responsible for kernel interaction with the daemon. The overall effect is that the portal daemon performs an open (2) on behalf of the kernel, possibly hiding substantial complexity from the calling process. One particularly useful application is implementing a connection service that allows simple scripts to open network sockets. This paper describes the implementation of portals for LINUX 2.0.

  2. The PLATO 2.0 Mission

    Science.gov (United States)

    Godolt, Mareike; Rauer, Heike; Plato Consortium

    2015-07-01

    The CHaracterising ExOPlanet Satellite (CHEOPS) is a joint ESA-Switzerland space mission dedicated to search for exoplanet transits by means of ultra-high precision photometry. It is expected to be launch-ready at the end of 2017. CHEOPS will be the first space observatory dedicated to search for transits on bright stars already known to host planets. It will have access to more than 70% of the sky. This will provide the unique capability of determining accurate radii for planets for which the mass has already been estimated from ground-based spectroscopic surveys and for new planets discovered by the next generation ground-based transits surveys (Neptune-size and smaller). The measurement of the radius of a planet from its transit combined with the determination of its mass through radial velocity techniques gives the bulk density of the planet, which provides direct insights into the structure and/or composition of the body. In order to meet the scientific objectives, a number of requirements have been derived that drive the design of CHEOPS. For the detection of Earth and super-Earth planets orbiting G5 dwarf stars with V-band magnitudes in the range 6 V 9 mag, a photometric precision of 20 ppm in 6 hours of integration time must be reached. This time corresponds to the transit duration of a planet with a revolution period of 50 days. In the case of Neptune-size planets orbiting K-type dwarf with magnitudes as faint as V=12 mag, a photometric precision of 85 ppm in 3 hours of integration time must be reached. The CHEOPS mission payload consists of only one instrument, a space telescope of 30 cm clear aperture, which has a single CCD focal plane detector. The total required duration of the CHEOPS mission is estimated to be 3.5 years (goal: 5 years).

  3. Tables of Shore and Fano parameters for the helium resonances 2s/sup 2/ /sup 1/S, 2p/sup 2/ /sup 1/D, and 2s 2p /sup 1/P excited in p-He collisions E/sub p/ = 33 to 150 keV

    Energy Technology Data Exchange (ETDEWEB)

    Bordenave-Montesquieu, A.; Benoit-Cattin, P.; Gleizes, A.; Merchez, H.

    1976-02-01

    Absolute values of Shore and Fano parameters are tabulated for the helium atom 2s/sup 2/ /sup 1/S, 2p/sup 2/ /sup 1/D, and 2s 2p /sup 1/P resonances produced by a proton beam. Observations were made on the spectra of ejected electrons. The important variation of the shape of the resonances with ejection angle is illustrated for E/sub p/ = 100 keV; the variation with proton energy is shown at 30/sup 0/.

  4. X-ray spectroscopy for chemistry in the 2-4 keV energy regime at the XMaS beamline: ionic liquids, Rh and Pd catalysts in gas and liquid environments, and Cl contamination in γ-Al2O3.

    Science.gov (United States)

    Thompson, Paul B J; Nguyen, Bao N; Nicholls, Rachel; Bourne, Richard A; Brazier, John B; Lovelock, Kevin R J; Brown, Simon D; Wermeille, Didier; Bikondoa, Oier; Lucas, Christopher A; Hase, Thomas P A; Newton, Mark A

    2015-11-01

    The 2-4 keV energy range provides a rich window into many facets of materials science and chemistry. Within this window, P, S, Cl, K and Ca K-edges may be found along with the L-edges of industrially important elements from Y through to Sn. Yet, compared with those that cater for energies above ca. 4-5 keV, there are relatively few resources available for X-ray spectroscopy below these energies. In addition, in situ or operando studies become to varying degrees more challenging than at higher X-ray energies due to restrictions imposed by the lower energies of the X-rays upon the design and construction of appropriate sample environments. The XMaS beamline at the ESRF has recently made efforts to extend its operational energy range to include this softer end of the X-ray spectrum. In this report the resulting performance of this resource for X-ray spectroscopy is detailed with specific attention drawn to: understanding electrostatic and charge transfer effects at the S K-edge in ionic liquids; quantification of dilution limits at the Cl K- and Rh L3-edges and structural equilibria in solution; in vacuum deposition and reduction of [Rh(I)(CO)2Cl]2 to γ-Al2O3; contamination of γ-Al2O3 by Cl and its potential role in determining the chemical character of supported Rh catalysts; and the development of chlorinated Pd catalysts in `green' solvent systems. Sample environments thus far developed are also presented, characterized and their overall performance evaluated.

  5. Characteristics of upstream energetic (E>=50keV) ion events during intense geomagnetic activity

    Science.gov (United States)

    Anagnostopoulos, G. C.; Rigas, A. G.; Sarris, E. T.; Krimigis, S. M.

    1998-05-01

    In this work we examine the statistical presence of some important features of upstream energetic (>=50 keV) ion events under some special conditions in the upstream region and the magnetosphere. The 125 ion events considered in the statistic were observed by the IMP 7 and IMP 8 spacecraft, at ~35RE from the Earth, during nine long time intervals of a total of 153 hours. The time intervals analyzed were selected under the following restrictions: existence of high proton flux (i.e., >=900 pcm-2s-1sr-1) and of a great number of events (an occurrence frequency of ~10 events per 12 hours in the whole statistics) in the energy range 50-220 keV. The most striking findings are the following: (1) The upstream events were observed during times with high values of the geomagnetic activity index Kp(>=3-) (2) all of the upstream events (100%) have energy spectra extending up to energies E>=290keV (3) 86% of these events are accompanied by relativistic (E>=220keV) electrons; and (4) the majority of the upstream ion events (82%) showed noninverse velocity dispersion during their onset phase (22% of the events showed forward velocity dispersion, and 60% showed no velocity dispersion at all when 5.5-min averaged observations were analyzed). Further statistical analysis of this sample of upstream particle events shows that the 50- to 220-keV proton flux shows a positive correlation with the following parameters: the Kp index of geomagnetic activity and the flux of the high-energy (290-500 keV) protons and (>=220 keV) electrons. More specific findings are the following: (1) The spectral index γ for a power law distribution of ions detected by the National Oceanic and Atmospheric Administration Energetic Particle Experiment (EPE) instrument (50=220-keV electrons increases with the time duration of upstream events. We infer that the vast majority of the upstream ion events considered in this study (under conditions of intense particle activity in the upstream region and enhanced

  6. New space research frequency band proposals in the 20- to 40.5-GHz range

    Science.gov (United States)

    Bishop, D. F.

    1991-01-01

    Future space research communications systems may require spectra above 20 GHz. Frequency bands above 20 GHz are identified that are suitable for space research. The selection of the proper bands depends on consideration of interference with other radio services, adequate bandwidths, link performance, and technical requirements for practical implementation.

  7. Die Bibliothek 2.0 ist tot – es lebe der Bibliothekar 2.0

    Directory of Open Access Journals (Sweden)

    David Tréfás

    2013-03-01

    Full Text Available Schweizer Bibliotheken bekunden Mühe mit ihren Auftritten im Internet. Insbesondere ihre Facebook-Seiten werden nur ungenügend genutzt. Dieser Artikel stellt die These in den Raum, wonach der Misserfolg der Bibliotheken vor allem darauf beruht, dass sie die Handlungsweisen ihrer Nutzer nicht der Umgebung des Web 2.0 anpassen. Erst wenn sich Bibliotheken als gleichberechtigte Mitglieder einer Community sehen, kann beispielsweise die Nutzung von Facebook wirklich gelingen.Swiss libraries have difficulties with their web presence. Especially their facebook pages are not being used sufficiently. This article suggests that the libraries’ failure is due to false expectations of user behaviour in a web 2.0 environment. Only if libraries regard themselves as equal members of a web community, can their web 2.0 presence and especially facebook presence unfold fully.

  8. Application of Web 2.0 Tools in Medical Librarianship to Support Medicine 2.0

    Directory of Open Access Journals (Sweden)

    V. Vishwa Mohan

    2008-03-01

    Full Text Available It is almost a decade that social networking technology along with its tools such as blogs, wikis, slidesharing/videosharing and photosharing softwares, podcasts, RSS feeds, mashups, folksonomies, and bookmarks has developed its influence on all human fields of study/activity. It is obvious that these tools are increasingly growing, in different languages, regions and fields, due to social dynamic and liberal characteristic of Web 2.0 technologies. Medical sciences and library science also are not exception to this influence. Consequently, library 2.0 and newly coined concepts of Medicine 2.0, and Health 2.0 have become the buzzwords in the Internet culture. In spite of proliferation of such social tools listed above, there is no aggregation and harmony for the utilization of the potential of these technologies in specific subject areas and the sources of information on the Web is almost proliferating and uncontrolled. This gives rise to the problem of webliographic control due to which the information seekers find difficulties in information retrieval. The paper presents application of Web 2.0 in medical libraries to support Medicine 2.0 emphasizing the above-mentioned problems. Considering the nature of an original article the experience of the authors, as a medical librarian and a faculty member in Library and Information Science, through observation of the needs, problems and prospects, played an important role in forming the idea and presentation. The study also used secondary data collected from related literatures. Standardization and webliographic control would solve the problem. In addition, governmental support and creating awareness at the management level in the organizations is also crucial.

  9. Fecal 20-oxo-pregnane concentrations in free-ranging African elephants (Loxodonta africana) treated with porcine zona pellucida vaccine.

    Science.gov (United States)

    Ahlers, M J; Ganswindt, A; Münscher, S; Bertschinger, H J

    2012-07-01

    Because of overpopulation of African elephants in South Africa and the consequent threat to biodiversity, the need for a method of population control has become evident. In this regard, the potential use of the porcine zona pellucida (pZP) vaccine as an effective means for population control is explored. While potential effects of pZP treatment on social behavior of African elephants have been investigated, no examination of the influence of pZP vaccination on the endocrine correlates in treated females has been undertaken. In this study, ovarian activity of free-ranging, pZP-treated African elephant females was monitored noninvasively for 1 yr at Thornybush Private Nature Reserve, South Africa, by measuring fecal 5α-pregnan-3β-ol-20-on concentrations via enzyme immunoassay. A total of 719 fecal samples from 19 individuals were collected over the study period, averaging 38 samples collected per individual (minimum, maximum: 16, 52). Simultaneously, behavioral observations were made to record the occurrence of estrous behavior for comparison. Each elephant under study showed 5α-pregnan-3β-ol-20-on concentrations rising above baseline at some period during the study indicating luteal activity. Average 5α-pregnan-3β-ol-20-on concentrations were 1.61 ± 0.46 μg/g (mean ± SD). Within sampled females, 42.9% exhibited estrous cycles within the range reported for captive African elephants, 14.3% had irregular cycles, and 42.9% did not appear to be cycling. Average estrous cycle duration was 14.72 ± 0.85 wk. Estrous behavior coincided with the onset of the luteal phase and a subsequent rise in 5α-pregnan-3β-ol-20-on concentrations. Average 5α-pregnan-3β-ol-20-on levels positively correlated with rainfall. No association between average individual 5α-pregnan-3β-ol-20-on concentrations or cyclicity status with age or parity were detected. Earlier determination of efficacy was established via fecal hormone analysis with no pregnancies determined 22 mo post

  10. From Web 2.0 to Learning Games 2.0

    DEFF Research Database (Denmark)

    Duus Henriksen, Thomas

    2011-01-01

    Learning games often fail in taking into account the extensive knowledge adult learners often have on the subject taught. This paper reports from a reconfiguration of a current learning game on leadership styles called LEADER, which on basis of ideas from web 2.0, is reconfigured to include...... the current and practical understandings brought by its participants. By inviting the participants into a semi-design process, the participants are asked to construct the game-content they would otherwise be playing. Results indicate that apart from being more time-consuming, LEADER 2.0 offers an effective...

  11. From web 2.0 to learning games 2.0

    DEFF Research Database (Denmark)

    Duus Henriksen, Thomas

    2011-01-01

    Learning games often fail in taking into account the extensive knowledge adult learners often have on the subject taught. This paper reports from a reconfiguration of a current learning game on leadership styles called LEADER, which on basis of ideas from web 2.0, is reconfigured to include...... the current and practical understandings brought by its participants. By inviting the participants into a semi-design process, the participants are asked to construct the game-content they would otherwise be playing. Results indicate that apart from being more time-consuming, LEADER 2.0 offers an effective...

  12. Extensional Lower Cretaceous volcanism in the Coastal Range (29°20'-30°S), Chile: geochemistry and petrogenesis

    Science.gov (United States)

    Morata, D.; Aguirre, L.

    2003-12-01

    Lower Cretaceous volcanism in the Coastal Range (29°20'-30°S) of Chile is mainly represented by highly porphyritic (20-30% phenocrysts) lavas with unzoned Ca-rich plagioclase (An 57-54Ab 40-42Or 3-4), clinopyroxene (Wo 40En 43Fs 17), magnetite, and minor idiomorphic, altered olivines. Geochemically, these lavas are characterized by a relative homogeneity with high Al 2O 3 and low MgO contents, and classified as high-K to shoshonitic basaltic andesites to andesites generated in an intra-arc extensional setting due to oblique subduction. Their isotopic geochemistry is characterized by highly homogeneous low initial Sr ratios (( 87Sr/ 86Sr) 0˜0.7036) and positive ɛNd values ( ɛNd=+2.9 to +4.7 ( 143Nd/ 144Nd) 0˜0.5127) that are very different from those proposed as representative of 'Andean-type' magmatism. A non-Andean modern setting dominated by subduction associated with intra-arc extension is proposed. On a ( 87Sr/ 86Sr) 0 versus ɛNd diagram, these lavas fit a model mixing curve for which the end members are Pacific MORB and Jurassic plutonic rocks from the Coastal Range. Coeval granitoids from the Coastal Range and lavas from the High Andes plot on the same field. Isotopically depleted mafic magmas could be metasomatized by the subducted sediments, which would increase their LILE content, and then partially contaminated by Jurassic plutonic rocks. The genesis of this magmatism may be related to a global low-spreading rate of 5 cm yr -1 in the southeast Pacific during 125-110 Ma.

  13. The G20 and the G2

    Institute of Scientific and Technical Information of China (English)

    Lin Hongyu

    2012-01-01

    Ovet the past four years, the G20 has greatly contributed to the stabilization of the world economic situation, helped to foster a cooperative spirit and avoid a global catastrophe such as the Great Depression of the 1930s. Because of this it has attracted significant world attention. What roles do China and the U.S. want the G20 to serve?

  14. Measurement of the bremsstrahlung spectra generated from thick targets with =2–78 under the impact of 10 keV electrons

    Indian Academy of Sciences (India)

    Namita Yadav; Pragya Bhatt; Raj Singh; V S Subrahmanyam; R Shanker

    2010-04-01

    We present new experimental data on thick target bremsstrahlung spectra generated from the interaction of energetic electrons with bulk matter. The ‘photon yields’ in terms of double differential cross-sections (DDCS) are measured for pure elements of thick targets: Ti ( = 22), Ag ( = 47), W ( = 74) and Pt ( = 78) under the impact of 10 keV electrons. Comparison of DDCS obtained from the experimental data is made with those predicted by Monte-Carlo (MC) calculations using PENELOPE code. A close agreement between the experimental data and the MC calculations is found for all the four targets within the experimental error of 16%. Furthermore, the ratios of DDCS of bremsstrahlung photons emitted from Ag, W and Pt with those from Ti as a function of photon energy are examined with a relatively lower uncertainty of about 10% and they are compared with MC calculations. A satisfactory agreement is found between the experiment and the calculations within some normalizing factors. The variations of DDCS as a function of Z and of photon energy are also studied which show that the DDCS vary closely with Z; however, some deviations are observed for ‘tip’ photons emitted from high Z targets.

  15. ViennaRNA Package 2.0

    Directory of Open Access Journals (Sweden)

    Lorenz Ronny

    2011-11-01

    Full Text Available Abstract Background Secondary structure forms an important intermediate level of description of nucleic acids that encapsulates the dominating part of the folding energy, is often well conserved in evolution, and is routinely used as a basis to explain experimental findings. Based on carefully measured thermodynamic parameters, exact dynamic programming algorithms can be used to compute ground states, base pairing probabilities, as well as thermodynamic properties. Results The ViennaRNA Package has been a widely used compilation of RNA secondary structure related computer programs for nearly two decades. Major changes in the structure of the standard energy model, the Turner 2004 parameters, the pervasive use of multi-core CPUs, and an increasing number of algorithmic variants prompted a major technical overhaul of both the underlying RNAlib and the interactive user programs. New features include an expanded repertoire of tools to assess RNA-RNA interactions and restricted ensembles of structures, additional output information such as centroid structures and maximum expected accuracy structures derived from base pairing probabilities, or z-scores for locally stable secondary structures, and support for input in fasta format. Updates were implemented without compromising the computational efficiency of the core algorithms and ensuring compatibility with earlier versions. Conclusions The ViennaRNA Package 2.0, supporting concurrent computations via OpenMP, can be downloaded from http://www.tbi.univie.ac.at/RNA.

  16. Merged Sounding VAP Version 2.0

    Energy Technology Data Exchange (ETDEWEB)

    Troyan, D.; Jensen, M.; Turner, D.; Miloshevich, L.

    2010-03-15

    The Merged Sounding Value-Added Product (VAP) has been in the ARM and ASR pipeline since 2001. Output data streams have been added to the Evaluation Products section of the ARM website for the past five years. Currently, there are data for all of the ACRF fixed sites and all deployments of the Mobile Facility. Fifty-three years of Merged Sounding data is available as an evaluation product. The process of moving all to the ARM Data Archive has been started and will be completed shortly. A second version of the Merged Sounding VAP was developed to address several concerns: (1) Vaisala radiosondes have inherent problems obtaining an accurate measurement of relative humidity, (2) the profile can be extended from 20 km to 60 km above ground level based upon the height achieved by ECMWF profiles, and (3) ECMWF temperatures require adjustments at high altitude (between 1mb and 100 mb). Solutions to these issues have been incorporated in the new version of this VAP. Along with producing that second version of Merged Sounding, a secondary data stream - Sonde Adjust - was created. This VAP incorporates any humidity corrections to the Vaisala RS-80, RS-90, and RS-92 radiosondes. The algorithms used to perform these corrections are documented by Wang et. al. (2002), Turner et. al. (2003), and Miloshevich et. al. (2004, 2009).

  17. Fra web 2.0 til læringsspil 2.0

    DEFF Research Database (Denmark)

    Duus Henriksen, Thomas

    2010-01-01

    Artiklen sætter fokus på, hvordan man kan omsætte web 2.0-teknologien til læringsspil for derigennem at skabe en brugerbaseret, deltagerdreven tilgang til at arbejde med læringsspil. Artiklen beretter om, hvordan organisationsudviklingsspillet 6Styles omsættes, først til en skoleudviklingssammenh......Artiklen sætter fokus på, hvordan man kan omsætte web 2.0-teknologien til læringsspil for derigennem at skabe en brugerbaseret, deltagerdreven tilgang til at arbejde med læringsspil. Artiklen beretter om, hvordan organisationsudviklingsspillet 6Styles omsættes, først til en...... skoleudviklingssammenhæng og dernæst til et såkaldt 2.0-læringsspil, hvor deltagerne skaber læringsspillets indhold, mens de spiller spillet. Erfaringer fra brug af læringsspillet peger på, at 1) 2.0 læringsspil tager markant mere tid at anvende, 2) deltagerne udvikler en produktiv forståelse for den underliggende teori...

  18. On the Emission of Electrons from Solid H_2 and D_2 by Bombardment with 1-3 keV Electrons up to Very Large Angles of Incidence

    DEFF Research Database (Denmark)

    Schou, Jørgen; Sørensen, H.

    1982-01-01

    Electron emission, i.e. electron reflection (ER) and secondary electron emission (SEE), was studied for solid H2 and D2 for oblique incidence of 1-3 keV electrons up to an angle of incidence θ of 83°. The ER coefficient η was small at low angles, and rose rapidly with increasing θ above 60......-65°. Only at large angles and low energies were the results different for H2 and D2, those for H2 being the lower ones. The angular variation of the SEE coefficient δ may be written as δ(θ)=δ(0)(cos θ)3/2 up to an angle of 65-75°. For H2 the SEE coefficient is around 0.65 times that the D2 except...... at the largest angles. The results agree well with the existing qualitative tendencies described in the literature. The variation with the angle of incidence shows a fair agreement with an estimate based on data for the angular distribution of electrons ejected from ionized hydrogen molecules. In addition...

  19. Atomic scattering in the diffraction limit: electron transfer in keV Li+-Na(3s, 3p) collisions

    DEFF Research Database (Denmark)

    Poel, Mike van der; Nielsen, C.V.; Rybaltover, M.

    2002-01-01

    We measure angle differential cross sections (DCS) in Li+ + Na --> Li + Na+ electron transfer collisions in the 2.7-24 keV energy range. We do this with a newly constructed apparatus which combines the experimental technique of cold target recoil ion momentum spectroscopy with a laser-cooled target...

  20. SOAP 2.0: Spot Oscillation And Planet 2.0

    Science.gov (United States)

    Dumusque, Xavier; Boisse, I.; Santos, N. C.

    2015-04-01

    SOAP (Spot Oscillation And Planet) 2.0 simulates the effects of dark spots and bright plages on the surface of a rotating star, computing their expected radial velocity and photometric signatures. It includes the convective blueshift and its inhibition in active regions.

  1. De la web 2.0 al elearning 2.0

    Directory of Open Access Journals (Sweden)

    Antonio Bartolomé Pina

    2012-05-01

    Full Text Available http://dx.doi.org/10.5007/2175-795X.2012v30n1p131 La Web 2.0 representa una segunda oportunidad para la introducción de los recursos y materiales multimedia en el sistema educativo. Este texto trata de plantear qué posibilidades está ofreciendo el multimedia a los entornos instruccionales latinoamericanos y por qué la Web 2.0 es una nueva oportunidad. Desde el 2004 el término Web 2.0 ha supuesto una revolución en los sitios de Internet, y ha generado algunas nuevas ideas educativas identificadas como “eLearning 2.0”. La ambigüedad de ambos términos no nos permite afirmar que nos encontramos ante un nuevo paradigma para la Educación a Distancia potenciada por la tecnología, pero parece que algunas ideas podrían provocar cambios en aspectos clave del currículum: la red como plataforma, o los sistemas multidispositivo cambian el concepto de estudiar en cualquier lugar y momento; la inteligencia colectiva y la riqueza de la experiencia del usuario afecta el concepto de autoridad en sistemas educativos; las etiquetas y los lectores RSS nos hacen revisar las taxonomías tradicionales así como la organización del conocimiento y la recuperación de la información.

  2. Oh! Web 2.0, Virtual Reference Service 2.0, Tools & Techniques (II)

    Science.gov (United States)

    Arya, Harsh Bardhan; Mishra, J. K.

    2012-01-01

    The paper describes the theory and definition of the practice of librarianship, specifically addressing how Web 2.0 technologies (tools) such as synchronous messaging, collaborative reference service and streaming media, blogs, wikis, social networks, social bookmarking tools, tagging, RSS feeds, and mashups might intimate changes and how…

  3. Web 2.0 and Critical Information Literacy

    Science.gov (United States)

    Dunaway, Michelle

    2011-01-01

    The impact of Web 2.0 upon culture, education, and knowledge is obfuscated by the pervasiveness of Web 2.0 applications and technologies. Web 2.0 is commonly conceptualized in terms of the tools that it makes possible, such as Facebook, Twitter, and Wikipedia. In the context of information literacy instruction, Web 2.0 is frequently conceptualized…

  4. The Warburg effect version 2.0

    Science.gov (United States)

    Menendez, Javier A.; Joven, Jorge; Cufí, Sílvia; Corominas-Faja, Bruna; Oliveras-Ferraros, Cristina; Cuyàs, Elisabet; Martin-Castillo, Begoña; López-Bonet, Eugeni; Alarcón, Tomás; Vazquez-Martin, Alejandro

    2013-01-01

    When fighting cancer, knowledge on metabolism has always been important. Today, it matters more than ever. The restricted cataloging of cancer genomes is quite unlikely to achieve the task of curing cancer, unless it is integrated into metabolic networks that respond to and influence the constantly evolving cancer stem cell (CSC) cellular states. Once the genomic era of carcinogenesis had pushed the 1920s Otto Warburg’s metabolic cancer hypothesis into obscurity for decades, the most recent studies begin to support a new developing paradigm, in which the molecular logic behind the conversion of non-CSCs into CSCs can be better understood in terms of the “metabolic facilitators” and “metabolic impediments” that operate as proximate openings and roadblocks, respectively, for the transcriptional events and signal transduction programs that ultimately orchestrate the intrinsic and/or microenvironmental paths to CSC cellular states. Here we propose that a profound understanding of how human carcinomas install a proper “Warburg effect version 2.0” allowing them to “run” the CSCs’ “software” programs should guide a new era of metabolo-genomic-personalized cancer medicine. By viewing metabolic reprogramming of CSCs as an essential characteristic that allows dynamic, multidimensional and evolving cancer populations to compete successfully for their expansion on the organism, we now argue that CSCs bioenergetics might be another cancer hallmark. A definitive understanding of metabolic reprogramming in CSCs may complement or to some extent replace, the 30-y-old paradigm of targeting oncogenes to treat human carcinomas, because it can be possible to metabolically create non-permissive or “hostile” metabotypes to prevent the occurrence of CSC cellular states with tumor- and metastasis-initiating capacity. PMID:23549172

  5. The 2-79 keV X-ray Spectrum of the Circinus Galaxy with NuSTAR, XMM-Newton and Chandra: a Fully Compton-Thick AGN

    CERN Document Server

    Arévalo, P; Puccetti, S; Walton, D J; Koss, M; Boggs, S E; Brandt, W N; Brightman, M; Christensen, F E; Comastri, A; Craig, W W; Fuerst, F; Gandhi, P; Grefenstette, B W; Hailey, C J; Harrison, F A; Luo, B; Madejski, G; Madsen, K K; Marinucci, A; Matt, G; Saez, C; Stern, D; Stuhlinger, M; Treister, E; Urry, C M; Zhang, W W

    2014-01-01

    The Circinus galaxy is one of the nearest obscured AGN, making it an ideal target for detailed study. Combining archival Chandra and XMM-Newton data with new NuSTAR observations, we model the 2-79 keV spectrum to constrain the primary AGN continuum and to derive physical parameters for the obscuring material. Chandra's high angular resolution allows a separation of nuclear and off-nuclear galactic emission. In the off-nuclear diffuse emission we find signatures of strong cold reflection, including high equivalent-width neutral Fe lines. This Compton-scattered off-nuclear emission amounts to 18% of the nuclear flux in the Fe line region, but becomes comparable to the nuclear emission above 30 keV. The new analysis no longer supports a prominent transmitted AGN component in the observed band. We find that the nuclear spectrum is consistent with Compton-scattering by an optically-thick torus, where the intrinsic spectrum is a powerlaw of photon index $\\Gamma = 2.2-2.4$, the torus has an equatorial column density...

  6. Effects of combined irradiation of 500 keV protons and atomic oxygen on polyimide films

    Science.gov (United States)

    Novikov, Lev; Chernik, Vladimir; Zhilyakov, Lev; Voronina, Ekaterina; Chirskaia, Natalia

    2016-07-01

    Polyimide films are widely used on the spacecraft surface as thermal control coating, films in different constuctions, etc. However, the space ionizing radiation of different types can alter the mechanical, optical and electrical properties of polyimide films. For example, it is well known that 20-100 keV proton irradiation causes breaking of chemical bonds and destruction of the surface layer in polyimide, deterioration of its optical properties, etc. In low-Earth orbits serious danger for polymeric materials is atomic oxygen of the upper atmosphere of the Earth, which is the main component in the range of heights of 200-800 km. Due to the orbital spacecraft velocity, the collision energy of oxygen atoms with the surface ( 5 eV) enhances their reactivity and opens additional pathways of their reaction with near-surface layers of materials. Hyperthermal oxygen atom flow causes erosion of the polyimide surface by breaking chemical bonds and forming of volatiles products (primarily, CO and CO _{2}), which leads to mass losses and degradation of material properties. Combined effect of protons and oxygen plasma is expected to give rise to synergistic effects enhancing the destruction of polyimide surface layers. This paper describes experimental investigation of polyimide films sequential irradiation with protons and oxygen plasma. The samples were irradiated by 500 keV protons at fluences of 10 ^{14}-10 ^{16} cm ^{-2} produced with SINP cascade generator KG-500 and 5-20 eV neutral oxygen atoms at fluence of 10 ^{20} cm ^{-2} generated by SINP magnetoplasmodynamics accelerator. The proton bombardment causes the decrease in optical transmission coefficient of samples, but their transmittance recovers partially after the exposure to oxygen plasma. The results of the comparative analysis of polyimide optical transmission spectra, Raman and XPS spectra obtained at different stages of the irradiation of samples, data on mass loss of samples due to erosion of the surface are

  7. 41 CFR 60-20.2 - Recruitment and advertisement.

    Science.gov (United States)

    2010-07-01

    ... advertisement. 60-20.2 Section 60-20.2 Public Contracts and Property Management Other Provisions Relating to... OF LABOR 20-SEX DISCRIMINATION GUIDELINES § 60-20.2 Recruitment and advertisement. (a) Employers... occupation qualification. (b) Advertisement in newspapers and other media for employment must not express...

  8. 36 CFR 222.2 - Management of the range environment.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Management of the range environment. 222.2 Section 222.2 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE... environment. (a) Allotments will be designated on the National Forest System and on other lands under...

  9. 20 CFR 418.1115 - What are the modified adjusted gross income ranges?

    Science.gov (United States)

    2010-04-01

    ... gross income range amounts by any percentage increase in the Consumer Price Index rounded to the nearest...) of this section. We will use your modified adjusted gross income amount together with your tax filing... from his/her spouse for the entire tax year for the year we use to make our income-related...

  10. Stopping power and mean free path for low-energy electrons in ten scintillators over energy range of 20-20,000 eV.

    Science.gov (United States)

    Tan, Zhenyu; Xia, Yueyuan

    2012-01-01

    Systematic calculations of the stopping powers (SP) and inelastic mean free paths (IMFP) for 20-20,000eV electrons in a group of 10 important scintillators have been carried out. The calculations are based on the dielectric model including the Born-Ochkur exchange correction and the optical energy loss functions (OELFs) are empirically evaluated because of the lack of available experimental optical data for the scintillators under consideration. The evaluated OELFs are examined by both the f-sum rule and the calculation of mean ionization potential. The SP and IMFP data presented here are the first results for the 10 scintillators over the energy range of 20-20,000eV, and are of key importance for the investigation of liquid scintillation counting.

  11. Search for a state at E{sub x} = 2.6 MeV in {sup 20}Na via the {sup 20}Ne(p,n) {sup 20}Na reaction and possible breakout from the hot CNO cycle

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, B.D.; Wetmore, B.; Baldwin, A.R. [and others

    1993-10-01

    At the high temperatures and densities present in supernovae explosions, hydrogen burning proceeds through the hot CNO cycle. At temperatures, T > 1 x 10{sup 8}K, this cycle may branch out through the reaction sequence {sup 15}O({alpha},{gamma}) {sup 19}Ne (p,{gamma}){sup 20}Na and begin a sequence of rapid proton captures and beta decays which can process CNO nuclei to form heavier elements and can increase energy production and will alter the elemental abundances of A = 20 to 30 nuclei significantly. The strength of this breakout is very sensitive to resonances in the {sup 19}Ne + p system, i.e., states in {sup 20}Na near the proton threshold of 2.199 MeV. A state was observed in the {sup 20}Ne({sup 3}He,t){sup 20}Na reaction at 2.6 MeV and reported to most likely be a 1{sup +} state. We performed a good resolution ({Delta}E {approx} 250 keV), low-background measurement of the {sup 20}Ne(p,n){sup 20}Na reaction at 135 MeV with the IUCF beam-swinger facility. We see no evidence for a 1{sup +} state in this experiment at 2.6 MeV; in fact, any state at 2.6 MeV is excited only weakly in the (p,n) reaction. Possible limits will be discussed.

  12. New x-ray parallel beam facility XPBF 2.0 for the characterization of silicon pore optics

    Science.gov (United States)

    Krumrey, Michael; Müller, Peter; Cibik, Levent; Collon, Max; Barrière, Nicolas; Vacanti, Giuseppe; Bavdaz, Marcos; Wille, Eric

    2016-07-01

    A new X-ray parallel beam facility (XPBF 2.0) has been installed in the laboratory of the Physikalisch-Technische Bundesanstalt at the synchrotron radiation facility BESSY II in Berlin to characterize silicon pore optics (SPOs) for the future X-ray observatory ATHENA. As the existing XPBF which is operated since 2005, the new beamline provides a pencil beam of very low divergence, a vacuum chamber with a hexapod system for accurate positioning of the SPO to be investigated, and a vertically movable CCD-based camera system to register the direct and the reflected beam. In contrast to the existing beamline, a multilayer-coated toroidal mirror is used for beam monochromatization at 1.6 keV and collimation, enabling the use of beam sizes between about 100 μm and at least 5 mm. Thus the quality of individual pores as well as the focusing properties of large groups of pores can be investigated. The new beamline also features increased travel ranges for the hexapod to cope with larger SPOs and a sample to detector distance of 12 m corresponding to the envisaged focal length of ATHENA.

  13. eGovernment 2.0 - How can Government benefit from web 2.0?

    Directory of Open Access Journals (Sweden)

    Soren Duus Ostergaard

    2008-12-01

    Full Text Available The purpose of this paper is to identify the major global trends in social computing/ collaborative computing as they seem to evolve under the 'web 2.0' heading, evaluate possible future trends seen from a technology point of view as well as from a socio-economic perspective and compare these trends to the current state and need for eGovernment. Finally, some general guidelines, ideas and projections for eGovernment will be proposed and discussed.

  14. From Web 2.0 to Learning Games 2.0

    DEFF Research Database (Denmark)

    Duus Henriksen, Thomas

    2011-01-01

    Learning games often fail in taking into account the extensive knowledge adult learners often have on the subject taught. This paper reports from a reconfiguration of a current learning game on leadership styles called LEADER, which on basis of ideas from web 2.0, is reconfigured to include...... approach to using games to teach in a case-based manner while allowing participants to develop an operational understanding of the underlying theories of the game....

  15. Ranging Behaviour of Commercial Free-Range Broiler Chickens 2: Individual Variation

    Science.gov (United States)

    Groves, Peter J.; Rault, Jean-Loup

    2017-01-01

    Simple Summary Although the consumption of free-range chicken meat has increased, little is known about the ranging behaviour of meat chickens on commercial farms. Studies suggest range use is low and not all chickens access the range when given the opportunity. Whether ranging behaviour differs between individuals within a flock remains largely unknown and may have consequences for animal welfare and management. We monitored individual chicken ranging behaviour from four mixed sex flocks on a commercial farm across two seasons. Not all chickens accessed the range. We identified groups of chickens that differed in ranging behaviour (classified by frequency of range visits): chickens that accessed the range only once, low frequency ranging chickens and high frequency ranging chickens, the latter accounting for one-third to one half of all range visits. Sex was not predictive of whether a chicken would access the range or the number of range visits, but males spent more time on the range in winter. We found evidence that free-range chicken ranging varies between individuals within the same flock on a commercial farm. Whether such variation in ranging behaviour relates to variation in chicken welfare remains to be investigated. Abstract Little is known about broiler chicken ranging behaviour. Previous studies have monitored ranging behaviour at flock level but whether individual ranging behaviour varies within a flock is unknown. Using Radio Frequency Identification technology, we tracked 1200 individual ROSS 308 broiler chickens across four mixed sex flocks in two seasons on one commercial farm. Ranging behaviour was tracked from first day of range access (21 days of age) until 35 days of age in winter flocks and 44 days of age in summer flocks. We identified groups of chickens that differed in frequency of range visits: chickens that never accessed the range (13 to 67% of tagged chickens), low ranging chickens (15 to 44% of tagged chickens) that accounted for <15

  16. Web 2.0 and health 2.0: are you in?

    Science.gov (United States)

    Felkey, Bill G

    2008-01-01

    With over 6 billion web pages, over $100 billion in online sales every year in the U.S. alone and the average growth rate of online purchasing exceeding 26% over the last 5 years, the Internet is a powerful business tool. Today's shopper sees your actual pharmacy location and your Internet presence as one and the same. One study showed that 82% of the consumers surveyed who had a single frustrating experience online with a retailer would not return to the site for future dealings. A bad experience online made 28% of those surveyed unlikely to return to the retail location of the business, and over 55% said a bad online experience would have a negative impact on their overall opinion of the retailer. Web 2.0 refers to the social networking applications of the internet, Health 2.0 to its special health applications. Taking your Internet presence to the 2.0 level must be balanced with all of the other demands you are facing-but be aware that it's happening all around you.

  17. Observational consistency and future predictions for a 3.5 keV ALP to photon line

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, Pedro D.; Conlon, Joseph P.; Day, Francesca V.; Marsh, M.C. David; Rummel, Markus [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford, OX1 3NP (United Kingdom)

    2015-04-09

    Motivated by the possibility of explaining the 3.5 keV line through dark matter decaying to axion-like particles that subsequently convert to photons, we study ALP-photon conversion for sightlines passing within 50 pc of the galactic centre. Conversion depends on the galactic centre magnetic field which is highly uncertain. For fields at low or mid-range of observational estimates (10–100 μG), no observable signal is possible. For fields at the high range of observational estimates (a pervasive poloidal mG field over the central 150 pc) it is possible to generate sufficient signal to explain recent observations of a 3.5 keV line in the galactic centre. In this scenario, the galactic centre line signal comes predominantly from the region with z>20pc, reconciling the results from the Chandra and XMM-Newton X-ray telescopes. The dark matter to ALP to photon scenario also naturally predicts the non-observation of the 3.5 keV line in stacked galaxy spectra. We further explore predictions for the line flux in galaxies and suggest a set of galaxies that is optimised for observing the 3.5 keV line in this model.

  18. Solar Advisor Model User Guide for Version 2.0

    Energy Technology Data Exchange (ETDEWEB)

    Gilman, P.; Blair, N.; Mehos, M.; Christensen, C.; Janzou, S.; Cameron, C.

    2008-08-01

    The Solar Advisor Model (SAM) provides a consistent framework for analyzing and comparing power system costs and performance across the range of solar technologies and markets, from photovoltaic systems for residential and commercial markets to concentrating solar power and large photovoltaic systems for utility markets. This manual describes Version 2.0 of the software, which can model photovoltaic and concentrating solar power technologies for electric applications for several markets. The current version of the Solar Advisor Model does not model solar heating and lighting technologies.

  19. A rigorous semantics for BPMN 2.0 process diagrams

    CERN Document Server

    Kossak, Felix; Geist, Verena; Kubovy, Jan; Natschläger, Christine; Ziebermayr, Thomas; Kopetzky, Theodorich; Freudenthaler, Bernhard; Schewe, Klaus-Dieter

    2015-01-01

    This book provides the most complete formal specification of the semantics of the Business Process Model and Notation 2.0 standard (BPMN) available to date, in a style that is easily understandable for a wide range of readers - not only for experts in formal methods, but e.g. also for developers of modeling tools, software architects, or graduate students specializing in business process management. BPMN - issued by the Object Management Group - is a widely used standard for business process modeling. However, major drawbacks of BPMN include its limited support for organizational modeling, i

  20. IDD 2.0: Physiological Resilience

    Science.gov (United States)

    2013-04-15

    homeostatic need to prevent further increases. Furthermore, efforts to increase heat dissipation will be recruited incrementally as body temperature...acceptable homeostatic range, then no reallocation of resources is necessary and no conditioning will occur. Similarly, if the activity is never...deployment simulation Page 53 of 62 suggests that the new caloric imbalance was still sufficient to trigger a reduction in long-term homeostasis, and

  1. Time-Resolved Cavity Nano-Optomechanics in the 20-100 GHz range

    CERN Document Server

    Anguiano, S; Jusserand, B; Favero, I; Lamperti, F R; Lanco, L; Sagnes, I; Lemaître, A; Lanzillotti-Kimura, N D; Senellart, P; Fainstein, A

    2016-01-01

    Applications of cavity optomechanics span from gravitational wave detection to the study of quantum motion states in mesoscopic mechanical systems. The engineering of resonators supporting strongly interacting mechanical and optical modes is central to these developments. However, current technological and experimental approaches limit the accessible mechanical frequencies to a few GHz, imposing hard constraints on quantum mechanical studies. Here we demonstrate the optical control of 20-100~GHz mechanical modes confined in the three dimensions within semiconductor nano-optomechanical pillar cavities. We use a time-resolved transient optical reflectivity technique and access both the energy spectrum and dynamics of the mechanical modes at the picosecond timescale. A strong increase of the optomechanical coupling upon reducing the pillar size is observed together with unprecedent room temperature Q-frequency products above $10^{14}$. The measurements also reveal sideband generation in the optomechanical respon...

  2. Short-range correlations in carbon-12, oxygen-16, and neon-20: Intrinsic properties

    Science.gov (United States)

    Braley, R. C.; Ford, W. F.; Becker, R. L.; Patterson, M. R.

    1972-01-01

    The Brueckner-Hartree-Fock (BHF) method has been applied to nuclei whose intrinsic structure is nonspherical. Reaction matrix elements were calculated as functions of starting energy for the Hamada-Johnston interaction using the Pauli operator appropriate to O-16 and a shifted oscillator spectrum for virtual excited states. Binding energies, single particle energies, radii, and shape deformations of the intrinsic state, in ordinary as well as renormalized BHF, are discussed and compared with previous HF studies and with experiment when possible. Results are presented for C-12, 0-16 and Ne-20. It is found that the binding energies and radii are too small, but that separation energies are well reproduced when the renormalized theory is used.

  3. Theoretical electron impact elastic, ionization and total cross sections for silicon hydrides, SiH{sub x} (x = 1, 2, 3, 4) and di-silane, Si{sub 2}H{sub 6} from threshold to 5 keV

    Energy Technology Data Exchange (ETDEWEB)

    Vinodkumar, M.; Korot, K. [V. P. and R. P. T. P. Science College, Vallabh Vidyanagar, Gujarat (India); Limbachiya, C. [P. S. Science College, Gujarat (India); Joshipura, K.N. [Sardar Patel Univ., Dept. of Physics, Gujarat (India)

    2008-07-15

    In this article we report comprehensive calculations of total elastic (Q{sub el}), and total ionization cross sections (Q{sub ion}), on silicon hydrides SiH{sub x} (x = 1-4) and di-silane, Si{sub 2}H{sub 6} on electron impact at energies from circa threshold to 2000 eV and total (complete) cross sections (Q{sub T}) up to 5 keV. Spherical complex optical potential (SCOP) formalism is employed to evaluate Q{sub el} and Q{sub T}. Total ionization cross sections are derived from total inelastic cross sections Q{sub inel}, using our complex spherical potential - ionization contribution (CSP-ic) method. Dependence of Q{sub T} on the dipole polarizability of the target and incident energy is presented for these targets through analytical formula, using which calculation of Q{sub T} is extended up to 5 keV. Comparison of Q{sub T} for all these targets is carried out to present a general theoretical picture of collision processes and also to visualize the dependence of Q{sub T} on the total number of electrons in the target and hence on the geometrical size of the target. Present calculations also provide information on the excitation processes of these targets. Present results are compared with available experimental and other theoretical data wherever available and overall good agreement is observed. There is probably no data for total elastic and total (complete) cross sections for SiH{sub x} (x = 2-3) in the present energy range and hence reported for the first time. (authors)

  4. Spectrometry of the Rutherford backscattering of ions and the Raman scattering of light in GaS single crystals irradiated with 140-keV H{sub 2}{sup +} ions

    Energy Technology Data Exchange (ETDEWEB)

    Garibov, A. A.; Madatov, R. S., E-mail: msrahim@mail.ru [Azerbaijan National Academy of Sciences, Institute of Radiation Problems (Azerbaijan); Komarov, F. F.; Pilko, V. V. [Belarus State University, RTCCU of “Nanotechnology and Physical Electronics” (Belarus); Mustafayev, Yu. M.; Akhmedov, F. I.; Jakhangirov, M. M. [Azerbaijan National Academy of Sciences, Institute of Radiation Problems (Azerbaijan)

    2015-05-15

    The methods of the Raman scattering of light and Rutherford backscattering are used to study the degree of structural disorder in layered GaS crystals before and after irradiation with 140-keV H{sub 2}{sup +} ions. It is shown that the distribution of the crystal’s components over depth is homogeneous; for doses as high as 5 × 10{sup 15} cm{sup −2}, the stoichiometric composition of the compound’s components is retained. The experimental value of the critical dose for the beginning of amorphization amounts to about 5 × 10{sup 15} cm{sup −2} and is in accordance with the calculated value. The results obtained by the method of the Raman scattering of light confirm conservation of crystalline structure and the start of the amorphization process.

  5. Calibration of Short Range 2D Laser Range Finder for 3D SLAM Usage

    OpenAIRE

    Petr Olivka; Michal Krumnikl; Pavel Moravec; David Seidl

    2016-01-01

    The laser range finder is one of the most essential sensors in the field of robotics. The laser range finder provides an accurate range measurement with high angular resolution. However, the short range scanners require an additional calibration to achieve the abovementioned accuracy. The calibration procedure described in this work provides an estimation of the internal parameters of the laser range finder without requiring any special three-dimensional targets. This work presents the use of...

  6. First measurements in search for keV sterile neutrino in tritium beta-decay in the Troitsk nu-mass experiment

    Science.gov (United States)

    Abdurashitov, J. N.; Belesev, A. I.; Chernov, V. G.; Geraskin, E. V.; Golubev, A. A.; Grigorieva, P. V.; Koroteev, G. A.; Likhovid, N. A.; Nozik, A. A.; Pantuev, V. S.; Parfenov, V. I.; Skasyrskaya, A. K.; Tkachev, I. I.; Zadorozhny, S. V.

    2017-06-01

    We present the first results of precision measurements of tritium -decay spectrum in the electron energy range 16-18.6 keV by the Troitsk nu-mass experiment. The goal is to find distortions that may be caused by the existence of heavy sterile neutrinos. A signature would correspond to a kink in the spectrum with characteristic shape and end point shifted by the value of a heavy neutrino mass. We set new upper limits to the neutrino mixing matrix element U e4 2 , which improve existing limits by a factor of 2 to 5 in the mass range of 0.1-2 keV.

  7. LS1 Report: injectors 2.0

    CERN Multimedia

    Anaïs Schaeffer

    2014-01-01

    Launched in 2009, the Accelerator Controls Renovation Project (ACCOR) will come to an end this year. It was brought in to replace the approximately 450 real-time control systems of the LHC injector complex, some of which were based on technology more than 20 years old.   One of the approximately 450 real-time systems that have been modified in the ACCOR project. These systems, which use special software and thousands of electronics boards, control devices that are essential to the proper functioning of the injectors – the radiofrequency system, the instrumentation, the injection kicker system, the magnets, etc. – and some of them were no longer capable of keeping pace with the LHC. As a result, they urgently needed to be upgraded. "In 2009, after assessing the new technology available on the market, we signed contracts with Europe's most cutting-edge electronics manufacturers," explains Marc Vanden Eynden, ACCOR Project Leader. We then quickly m...

  8. r-Java 2.0: the nuclear physics

    CERN Document Server

    Kostka, M; Shand, Z; Ouyed, R; Jaikumar, P

    2014-01-01

    [Aims:] We present r-Java 2.0, a nucleosynthesis code for open use that performs r-process calculations as well as a suite of other analysis tools. [Methods:] Equipped with a straightforward graphical user interface, r-Java 2.0 is capable of; simulating nuclear statistical equilibrium (NSE), calculating r-process abundances for a wide range of input parameters and astrophysical environments, computing the mass fragmentation from neutron-induced fission as well as the study of individual nucleosynthesis processes. [Results:] In this paper we discuss enhancements made to this version of r-Java, paramount of which is the ability to solve the full reaction network. The sophisticated fission methodology incorporated into r-Java 2.0 which includes three fission channels (beta-delayed, neutron-induced and spontaneous fission) as well as computation of the mass fragmentation is compared to the upper limit on mass fission approximation. The effects of including beta-delayed neutron emission on r-process yield is studi...

  9. Muutuste teel : raamatukogu 2.0 / Kate-Riin Kont

    Index Scriptorium Estoniae

    Kont, Kate-Riin, 1971-

    2007-01-01

    7.-10. maini 2007. a Helsingis ja Tallinnas toimunud raamatukogufoorumist "Muutuste teel: Library 2.0 (Making a difference - Moving towards Library 2.0), millel esines ettekandega suhteturundusest Tallinna Ülikooli infoteaduse osakonna dotsent Aira Lepik

  10. Muutuste teel : raamatukogu 2.0 / Kate-Riin Kont

    Index Scriptorium Estoniae

    Kont, Kate-Riin, 1971-

    2007-01-01

    7.-10. maini 2007. a Helsingis ja Tallinnas toimunud raamatukogufoorumist "Muutuste teel: Library 2.0 (Making a difference - Moving towards Library 2.0), millel esines ettekandega suhteturundusest Tallinna Ülikooli infoteaduse osakonna dotsent Aira Lepik

  11. Erosion of solid neon by keV electrons

    DEFF Research Database (Denmark)

    Schou, Jørgen; Børgesen, P.; Ellegaard, Ole;

    1986-01-01

    The erosion of solid neon by keV electrons has been studied experimentally and theoretically. Electronic sputtering as well as temperature-enhanced sublimation are investigated by a frequency-change measurement on a quartz crystal or in some cases by the change in intensity of reflected electrons....... The erosion yield increases with increasing temperature for substrate temperatures above 7K. Below this temperature sputtering via electronic transitions is the dominant process. The yield shows a clear minimum for film thicknesses about (5-7)×1016 Ne atoms/cm2 for 2-keV electrons. The sputtering yield...

  12. Prevention 2.0: targeting cyberbullying @ school.

    Science.gov (United States)

    Wölfer, Ralf; Schultze-Krumbholz, Anja; Zagorscak, Pavle; Jäkel, Anne; Göbel, Kristin; Scheithauer, Herbert

    2014-12-01

    Although cyberbullying is characterized by worrying prevalence rates and associated with a broad range of detrimental consequences, there is a lack of scientifically based and evaluated preventive strategies. Therefore, the present study introduces a theory-based cyberbullying prevention program (Media Heroes; German original: Medienhelden) and evaluates its effectiveness. In a pretest-posttest design (9-month interval), schools were asked to randomly assign their participating classes to either control or intervention group. Longitudinal data were available from 593 middle school students (M Age = 13.3 years, 53 % girls) out of 35 classes, who provided information on cyberbullying behavior as well as socio-demographic and psychosocial variables. While the present results revealed worrying prevalence rates of cyberbullying in middle school, multilevel analyses clearly demonstrate the program's effectiveness in reducing cyberbullying behavior within intervention classes in contrast to classes of the control group. Hence, this study presents a promising program which evidentially prevents cyberbullying in schools.

  13. Enterprise Information System Architecture Based on Web 2.0

    Institute of Scientific and Technical Information of China (English)

    YI Xiushuang; WANG Yu; LIU Jinghong; WEN Zhankao

    2006-01-01

    Enterprise information systems with a great use of Web 2.0 technologies will be more open, free, and more efficient.With the contrast between classic Web technologies and Web 2.0 technologies, we represent a sample of enterprise information system based on Web 2.0, and show how the use of Web 2.0 technologies changes the system data exchange model of the enterprise information systems and how it improves the efficiency and effectiveness of information systems.

  14. Modelling of the implantation and the annealing stages of 800 keV {sup 3}He implanted tungsten: Formation of nanovoids in the near surface region

    Energy Technology Data Exchange (ETDEWEB)

    De Backer, A., E-mail: andree.de-backer@univ-lille1.fr [Unite Materiaux Et Transformations, UMET, UMR 8207, Universite de Lille 1, F-59655 Villeneuve d' Ascq (France); Laboratoire commun EDF-CNRS Etude et Modelisation des Microstructures pour le Vieillissement des Materiaux (EM2VM) (France); Lhuillier, P.E. [CNRS, UPR3079 CEMHTI, 1D Avenue de la Recherche Scientifique, 45071 Orleans cedex 2 (France); Universite d' Orleans, Faculte des Sciences, Avenue du Parc Floral, BP 6749, 45067 Orleans cedex 2 (France); Becquart, C.S. [Unite Materiaux Et Transformations, UMET, UMR 8207, Universite de Lille 1, F-59655 Villeneuve d' Ascq (France); Laboratoire commun EDF-CNRS Etude et Modelisation des Microstructures pour le Vieillissement des Materiaux (EM2VM) (France); Barthe, M.F. [CNRS, UPR3079 CEMHTI, 1D Avenue de la Recherche Scientifique, 45071 Orleans cedex 2 (France); Universite d' Orleans, Faculte des Sciences, Avenue du Parc Floral, BP 6749, 45067 Orleans cedex 2 (France)

    2012-10-15

    The formation of voids in tungsten implanted at room temperature with 800 keV {sup 3}He atoms and subsequently annealed from 300 K to 900 K is modelled using an Object Kinetic Monte Carlo code. Different fluences are investigated ranging from 10{sup 17} to 5 Multiplication-Sign 10{sup 20} ions m{sup -2} and comparisons are made with Positron Annihilation Spectroscopy results. Good agreements with the experimental results are obtained regarding the temperature range at which the vacancy clustering occurs and the dependency of the nanovoid size with fluence. Despite the small amount of He atoms in the investigated region named 'track region', their role is underlined and it is shown that they act as nuclei for the nanovoid formation. The non trivial consequence is that the higher the fluence, the smaller the nanovoids in the track region.

  15. 42 CFR 2.20 - Relationship to State laws.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Relationship to State laws. 2.20 Section 2.20 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CONFIDENTIALITY OF ALCOHOL AND DRUG ABUSE PATIENT RECORDS General Provisions § 2.20 Relationship to State laws...

  16. Using web 2.0 for health information

    CERN Document Server

    Younger, Paula

    2011-01-01

    Since it was first formally described in 2004, what is known as Web 2.0 has affected every library and information sector. Web 2.0 has tremendous potential to transform health information delivery. This book offers a cohesive overview of how Web 2.0 is changing health and medical information work.

  17. Exploring Library 2.0 on the Social Web

    Science.gov (United States)

    Brantley, John S.

    2010-01-01

    Library 2.0 literature has described many of the possibilities Web 2.0 technologies offer to libraries. Case studies have assessed local use, but no studies have measured the Library 2.0 phenomenon by searching public social networking sites. This study used library-specific terms to search public social networking sites, blog search engines, and…

  18. Deriving a Typology of Web 2.0 Learning Technologies

    Science.gov (United States)

    Bower, Matt

    2016-01-01

    This paper presents the methods and outcomes of a typological analysis of Web 2.0 technologies. A comprehensive review incorporating over 2000 links led to identification of over 200 Web 2.0 technologies that were suitable for learning and teaching purposes. The typological analysis involved development of relevant Web 2.0 dimensions, grouping…

  19. Dynamic properties of Indiana, Fort Knox and Utah test range limestones and Danby Marble over the stress range 1 to 20 GPa

    Energy Technology Data Exchange (ETDEWEB)

    Furnish, M.D.

    1994-12-01

    The responses of the following carbonate materials to shock loading and release have been measured: Indiana limestone (18% porosity; saturated and dry), Jeffersonville/Louisville Limestones (Fort Knox limestone) (variable dolomitization, low porosity), Danby Marble (essentially pure calcite; low porosity), and a limestone from the Utah Test and Training Range (low porosity, with 22% silica). Various experimental configurations were used, some optimized to yield detailed waveform information, others to yield a clean combination of Hugoniot states and release paths. All made use of velocity interferometry as a primary diagnostic. The stress range of 0 - 20 GPa was probed (in most cases, emphasizing the stress range 0 -10 GPa). The primary physical processes observed in this stress regime were material strength, porosity, and polymorphic phase transitions between the CaCO{sub 3} phases I, II, III and VI. Hydration was also a significant reaction under certain conditions. The Indiana Limestone studies in particular represent a significant addition to the low-pressure database for porous limestone. Temperature dependence and the effect of freezing were assessed for the Fort Knox limestone. Experimental parameters and detailed results are provided for the 42 impact tests in this series.

  20. EXTJS2.0客户端调用Rails的REST%EXTJS2.0 Client Need Transfer REST of Rails2.0

    Institute of Scientific and Technical Information of China (English)

    王一锋

    2008-01-01

    Rails是一个敏捷的Web开发框架,Rails2.0中REST被作为主要的运用,而EXTJS2.0是一个Javaacript编写的Web界面库.本文提出了一个如何使用EXTJS组件调用Rails的REST的解决方法.

  1. The blazar sequence 2.0

    CERN Document Server

    Ghisellini, Gabriele

    2016-01-01

    I discuss the spectral energy distribution (SED) of all blazars with redshift detected by the {\\it Fermi} satellite and listed in the 3LAC catalog. I will update the so called "blazar sequence" from the phenomenological point of view, with no theory or modelling. I will show that: i) pure data show that jet and accretion power are related; ii) the updated blazar sequence maintains the properties of the old version, albeit with a less pronounced dominance of the $\\gamma$--ray emission; iii) at low bolometric luminosities, two different type of objects have the same high energy power: low black hole mass flat spectrum radio quasars and high mass BL Lacs. Therefore, at low luminosities, there is a very large dispersion of SED shapes; iv) in low power BL Lacs, the contribution of the host galaxy is important. Remarkably, the luminosity distribution of the host galaxies of BL Lacs are spread in a very narrow range; v) a simple sum of two smoothly joining power laws can describe the blazar SEDs very well.

  2. Parrot AR.Drone 2.0

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Parrot AR.Drone 2.0是极客们的超级玩具。它搭载Wi-Fi功能,可以用智能手机遥控。上面的摄像头能够实时将采集的画面发送到iOS或Android设备上。Parrot AR.Drone 2.0比前辈技巧更强。你会对它爱不释手……

  3. 2 CFR 230.20 - Applicability.

    Science.gov (United States)

    2010-01-01

    ... federally-recognized Indian tribal government, 2 CFR part 225 shall apply. (c) Exclusion of some non-profit... all Federal agencies in determining the costs of work performed by non-profit organizations under... concerned. Thus, if a subaward is to a non-profit organization, this part shall apply; if a subaward is to...

  4. The EUROCALL Review, Volume 20, Number 2

    Science.gov (United States)

    Gimeno, Ana, Ed.

    2012-01-01

    "The EUROCALL Review" is published online biannually by the European Association for Computer-Assisted Language Learning (EUROCALL). This issue offers regular sections on: (1) up-to-date information on Special Interest Groups; (2) reports on on-going CALL or CALL-related R&D projects in which EUROCALL members participate; (3) reports…

  5. Calibration of Short Range 2D Laser Range Finder for 3D SLAM Usage

    Directory of Open Access Journals (Sweden)

    Petr Olivka

    2016-01-01

    Full Text Available The laser range finder is one of the most essential sensors in the field of robotics. The laser range finder provides an accurate range measurement with high angular resolution. However, the short range scanners require an additional calibration to achieve the abovementioned accuracy. The calibration procedure described in this work provides an estimation of the internal parameters of the laser range finder without requiring any special three-dimensional targets. This work presents the use of a short range URG-04LX scanner for mapping purposes and describes its calibration. The precision of the calibration was checked in an environment with known ground truth values and the results were statistically evaluated. The benefits of the calibration are also demonstrated in the practical applications involving the segmentation of the environment. The proposed calibration method is complex and detects all major manufacturing inaccuracies. The procedure is suitable for easy integration into the current manufacturing process.

  6. IntelliGrow 2.0

    DEFF Research Database (Denmark)

    Markvart, Jakob; Aaslyng, Jesper Peter Mazanti; Kalita, Sebastian;

    2008-01-01

    the system in full scale in five Danish commercial nurseries. The four steps to reach the goal are: 1) development of a demonstrator giving the grower advice on optimal climate control based on the IntelliGrow concept 2) testing the demonstrator at research facilities followed by tests at growers 3...... production management and resource utilization. A fast flow of knowledge from research to practice in the future will be established. Design of the concept and the first results are presented in this paper....

  7. Instant Zend Framework 2.0

    CERN Document Server

    Hasan, A N M Mahabubul

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. This book is fast-paced, practical guide that will provide step-by-step instructions for building a practical database-driven MVC application using Zend Framework 2.This book is for developers who possess entry level knowledge or who have no prior experience with Zend Framework. An understanding of object-oriented programming is important and experience with namespaces will be required.

  8. High Optical Access Trap 2.0.

    Energy Technology Data Exchange (ETDEWEB)

    Maunz, Peter Lukas Wilhelm [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-01-26

    The High Optical Access (HOA) trap was designed in collaboration with the Modular Universal Scalable Ion-trap Quantum Computer (MUSIQC) team, funded along with Sandia National Laboratories through IARPA's Multi Qubit Coherent Operations (MQCO) program. The design of version 1 of the HOA trap was completed in September 2012 and initial devices were completed and packaged in February 2013. The second version of the High Optical Access Trap (HOA-2) was completed in September 2014 and is available at IARPA's disposal.

  9. CRM的2.0冲动

    Institute of Scientific and Technical Information of China (English)

    王占波

    2008-01-01

    当人们还在质疑Web2.0的风潮将如何影响传统CRM之时,一家传统行业的领导者却开始实地应用,并取得了不错的效果。来自瑞士的Holcim Lanka公司是全球水泥制造行业的领导者,通过应用Oracle CRM On Demand解决方案,提升了销售效率。该公司市场负责人Smriti Kinsley表示:“我们采用的Oracle CRM On Demand解决方案,尤其是Oracle移动销售助理软件,将极大地提高销售效率和对客户需求的响应速度,甚至在网络没有覆盖到的区域也一样。”当然,他也坚信,使用Web2.0技术将会促进公司与客户、供应商、员工以及合作伙伴的协作。

  10. 7.1 keV sterile neutrino constraints from X-ray observations of 33 clusters of galaxies with Chandra ACIS

    CERN Document Server

    Hofmann, F; Nandra, K; Clerc, N; Gaspari, M

    2016-01-01

    Recently an unidentified emission line at 3.55 keV has been detected in X-ray spectra of clusters of galaxies. The line has been discussed as a possible decay signature of 7.1 keV sterile neutrinos, which have been proposed as a dark matter candidate. We aim at putting constraints on the proposed line emission in a large sample of Chandra-observed clusters and obtain limits on the mixing-angle in a 7.1 keV sterile neutrino dark matter scenario. For a sample of 33 high-mass clusters of galaxies we merge all observations from the Chandra data archive. Each cluster has more than 100 ks of combined exposure. The resulting high signal-to-noise spectra are used to constrain the flux of an unidentified line emission at 3.55 keV in the individual spectra and a merged spectrum of all clusters. We obtained very detailed spectra around the 3.55 keV range and limits on an unidentified emission line. Assuming all dark matter were made of 7.1 keV sterile neutrinos the upper limits on the mixing angle are $\\rm{sin^2(2\\Theta...

  11. Hard x-ray broad band Laue lenses (80 - 600 keV): building methods and performances

    CERN Document Server

    Virgilli, E; Rosati, P; Liccardo, V; Squerzanti, S; Carassiti, V; Caroli, E; Auricchio, N; Stephen, J B

    2015-01-01

    We present the status of the laue project devoted to develop a technology for building a 20 meter long focal length Laue lens for hard x-/soft gamma-ray astronomy (80 - 600 keV). The Laue lens is composed of bent crystals of Gallium Arsenide (GaAs, 220) and Germanium (Ge, 111), and, for the first time, the focusing property of bent crystals has been exploited for this field of applications. We show the preliminary results concerning the adhesive employed to fix the crystal tiles over the lens support, the positioning accuracy obtained and possible further improvements. The Laue lens petal that will be completed in a few months has a pass band of 80 - 300 keV and is a fraction of an entire Laue lens capable of focusing X-rays up to 600 keV, possibly extendable down to 20 - 30 keV with suitable low absorption crystal materials and focal length. The final goal is to develop a focusing optics that can improve the sensitivity over current telescopes in this energy band by 2 orders of magnitude.

  12. Ellipsometry and energy characterization of the electron impact polymerization in the range 0-20 eV

    Science.gov (United States)

    Zyn, V. I.

    2016-05-01

    The electron impact polymerization of adsorbed vapors of a hydrocarbon vacuum oil with molecular mass 450 Da (C32H66) has been studied in-situ in the range 0-20 eV using ellipsometry and a servo system with the Kelvin's vibrating probe. This allowed registering at the same time the two energy-dependent characteristics (spectra) of the process: the film growth rate and the electrical potential of the irradiated surface. The first spectrum has two resonance maxima near 2.5 and 9.5 eV while the surface potential has only one weak extremum near 9.5 eV. The first growth rate peak at 2.5 eV was connected with a creation of radicals through a resonant process of the dissociative electron attachment and beginning polymerization. The peaks at 9.5 eV in both the spectra mean accelerating polymerization and decreasing surface charge owing to simultaneous birth of highly active radicals and free electrons. The single resonant process controlling both the processes simultaneously is the dissociative attachment of an electron to an anti-bonding molecular orbital, almost the same as at the 2.5 eV but differing by deeper decomposition of the transient anion, among the products of which are now not the radicals only but also free electrons. The kinetic curves obtained in pulsed regimes of the electron bombardment were qualitatively identical for different precursors and were used for calculations of cross sections of these processes.

  13. BioCat 2.0

    Energy Technology Data Exchange (ETDEWEB)

    Corley, Courtney D.; Noonan, Christine F.; Bartholomew, Rachel A.; Franklin, Trisha L.; Hutchison, Janine R.; Lancaster, Mary J.; Madison, Michael C.; Piatt, Andrew W.

    2013-09-16

    The U.S. Department of Homeland Security (DHS) National Biosurveillance Integration Center (NBIC) was established in 2008 with a primary mission to “(1) enhance the capability of the Federal Government to (A) rapidly identify, characterize, localize, and track a biological event of national concern by integrating and analyzing data relating to human health, animal, plant, food, and environmental monitoring systems (both national and international); and (B) disseminate alerts and other information to Member Agencies and, in coordination with (and where possible through) Member Agencies, to agencies of State, local, and tribal governments, as appropriate, to enhance the ability of such agencies to respond to a biological event of national concern; and (2) oversee development and operation of the National Biosurveillance Integration System (NBIS).” Inherent in its mission then and the broader NBIS, NBIC is concerned with the identification, understanding, and use of a variety of biosurveillance models and systems. The goal of this project is to characterize, evaluate, classify, and catalog existing disease forecast and prediction models that could provide operational decision support for recognizing a biological event having a potentially significant impact. Additionally, gaps should be identified and recommendations made on using disease models in an operational environment to support real-time decision making.

  14. Electronic stopping of keV nitrogen ions interacting with a Pt(110) (1 x 2) surface - a tool to characterize electronic surfaces

    NARCIS (Netherlands)

    Robin, A; Postnikov, AV; Heiland, W

    2005-01-01

    Ion channeling is used to investigate the electronic density corrugation at surfaces by analysing the electronic stopping behaviour of ions scattering grazingly off a clean single crystalline Pt(110)(1 x 2) surface. We use the fact that under these conditions the elastic contribution can be separate

  15. The Space Complexity of 2-Dimensional Approximate Range Counting

    DEFF Research Database (Denmark)

    Wei, Zhewei; Yi, Ke

    2013-01-01

    with additive error εn. A well-known solution for this problem is the ε-approximation. Informally speaking, an ε-approximation of P is a subset A ⊆ P that allows us to estimate the number of points in P ∩ R by counting the number of points in A ∩ R. It is known that an ε-approximation of size exists for any P......We study the problem of 2-dimensional orthogonal range counting with additive error. Given a set P of n points drawn from an n × n grid and an error parameter ε, the goal is to build a data structure, such that for any orthogonal range R, the data structure can return the number of points in P ∩ R...

  16. Charge state distributions and charge exchange cross sections of carbon in helium at 30-258 keV

    Science.gov (United States)

    Maxeiner, Sascha; Seiler, Martin; Suter, Martin; Synal, Hans-Arno

    2015-10-01

    With the introduction of helium stripping in radiocarbon (14C) accelerator mass spectrometry (AMS), higher +1 charge state yields in the 200 keV region and fewer beam losses are observed compared to nitrogen or argon stripping. To investigate the feasibility of even lower beam energies for 14C analyses the stripping characteristics of carbon in helium need to be further studied. Using two different AMS systems at ETH Zurich (myCADAS and MICADAS), ion beam transmissions of carbon ions for the charge states -1, +1, +2 and +3 were measured in the range of 258 keV down to 30 keV. The correction for beam losses and the extraction of charge state yields and charge exchange cross sections will be presented. An increase in population of the +1 charge state towards the lowest measured energies up to 75% was found as well as agreement with previous data from literature. The findings suggest that more compact radiocarbon AMS systems are possible and could provide even higher efficiency than current systems operating in the 200 keV range.

  17. NONCODE v2.0: decoding the non-coding.

    Science.gov (United States)

    He, Shunmin; Liu, Changning; Skogerbø, Geir; Zhao, Haitao; Wang, Jie; Liu, Tao; Bai, Baoyan; Zhao, Yi; Chen, Runsheng

    2008-01-01

    The NONCODE database is an integrated knowledge database designed for the analysis of non-coding RNAs (ncRNAs). Since NONCODE was first released 3 years ago, the number of known ncRNAs has grown rapidly, and there is growing recognition that ncRNAs play important regulatory roles in most organisms. In the updated version of NONCODE (NONCODE v2.0), the number of collected ncRNAs has reached 206 226, including a wide range of microRNAs, Piwi-interacting RNAs and mRNA-like ncRNAs. The improvements brought to the database include not only new and updated ncRNA data sets, but also an incorporation of BLAST alignment search service and access through our custom UCSC Genome Browser. NONCODE can be found under http://www.noncode.org or http://noncode.bioinfo.org.cn.

  18. The Web 2.0 as Marketing Tool: Opportunities for SMEs

    NARCIS (Netherlands)

    Constantinides, Efthymios

    2008-01-01

    The new generation of Internet applications widely known as Social Media or Web 2.0 offers corporations a whole range of opportunities for improving their marketing efficiency and internal operations. Web 2.0 applications have already become part of the daily life of an increasing number of consumer

  19. The Web 2.0 as Marketing Tool: Opportunities for SMEs

    NARCIS (Netherlands)

    Constantinides, Efthymios

    2008-01-01

    The new generation of Internet applications widely known as Social Media or Web 2.0 offers corporations a whole range of opportunities for improving their marketing efficiency and internal operations. Web 2.0 applications have already become part of the daily life of an increasing number of consumer

  20. The Web 2.0 as Marketing Tool: Opportunities for SMEs

    NARCIS (Netherlands)

    Constantinides, Efthymios

    2008-01-01

    The new generation of Internet applications widely known as Social Media or Web 2.0 offers corporations a whole range of opportunities for improving their marketing efficiency and internal operations. Web 2.0 applications have already become part of the daily life of an increasing number of

  1. Mobility2.0: co-operative ITS systems for enhanced electric vehicle mobility

    NARCIS (Netherlands)

    Unknown, [Unknown; Dimitrova, D.C.; Brogle, M.; Braun, T.; Heijenk, Gerhard J.

    Mobility2.0 will develop and test an in-vehicle commuting assistant for FEV mobility, resulting in more reliable and energy-efficient electro-mobility. In order to achieve a maximum impact, Mobility2.0 takes an integrated approach of ad- dressing the main bottlenecks of urban FEV mobility: range

  2. Mobility2.0: co-operative ITS systems for enhanced electric vehicle mobility

    NARCIS (Netherlands)

    Heijenk, G.; Dimitrova, D.C.; Brogle, M.; Braun, T.; Heijenk, G.J.

    2013-01-01

    Mobility2.0 will develop and test an in-vehicle commuting assistant for FEV mobility, resulting in more reliable and energy-efficient electro-mobility. In order to achieve a maximum impact, Mobility2.0 takes an integrated approach of ad- dressing the main bottlenecks of urban FEV mobility: range anx

  3. Evaluating HDR photos using Web 2.0 technology

    Science.gov (United States)

    Qiu, Guoping; Mei, Yujie; Duan, Jiang

    2011-01-01

    High dynamic range (HDR) photography is an emerging technology that has the potential to dramatically enhance the visual quality and realism of digital photos. One of the key technical challenges of HDR photography is displaying HDR photos on conventional devices through tone mapping or dynamic range compression. Although many different tone mapping techniques have been developed in recent years, evaluating tone mapping operators prove to be extremely difficult. Web2.0, social media and crowd-sourcing are emerging Internet technologies which can be harnessed to harvest the brain power of the mass to solve difficult problems in science, engineering and businesses. Paired comparison is used in the scientific study of preferences and attitudes and has been shown to be capable of obtaining an interval-scale ordering of items along a psychometric dimension such as preference or importance. In this paper, we exploit these technologies for evaluating HDR tone mapping algorithms. We have developed a Web2.0 style system that enables Internet users from anywhere to evaluate tone mapped HDR photos at any time. We adopt a simple paired comparison protocol, Internet users are presented a pair of tone mapped images and are simply asked to select the one that they think is better or click a "no difference" button. These user inputs are collected in the web server and analyzed by a rank aggregation algorithm which ranks the tone mapped photos according to the votes they received. We present experimental results which demonstrate that the emerging Internet technologies can be exploited as a new paradigm for evaluating HDR tone mapping algorithms. The advantages of this approach include the potential of collecting large user inputs under a variety of viewing environments rather than limited user participation under controlled laboratory environments thus enabling more robust and reliable quality assessment. We also present data analysis to correlate user generated qualitative

  4. Web 2.0 Learning Environment: Concept, Implementation, Evaluation

    OpenAIRE

    Blees, Ingo; Rittberger, Marc

    2009-01-01

    This contribution presents and evaluates a new learning environment model based on Web 2.0 applications. In a theoretical overview the concepts of eLearning 2.0 and Personal Learning Environments are introduced, along with their main aspects of autonomy, creativity and networking, and relate them to the didactics of constructivism and connectivism. The requirements and basic functional components for the development of our particular Web 2.0 learning environment are derived from these. The le...

  5. Latitude variation of recurrent MeV-energy proton flux enhancements in the heliocentric radial range 11 to 20 AU and possible correlation with solar coronal hole dynamics

    Science.gov (United States)

    Christon, S. P.; Stone, E. C.

    1985-01-01

    Recurrent low energy (not less than 0.5 MeV) proton flux enhancements, reliable indicators of corotating plasma interaction regions in interplanetary space, have been observed on the Voyager 1 and 2 and Pioneer 11 spacecraft in the heliographic latitude range 2 deg S to 23 deg N and the heliocentric radial range 11 to 20 AU. After a period of rather high correlation between fluxes at different latitudes in early 1983, distinct differences develop. The evolution of the fluxes appears to be related to the temporal and latitudinal dynamics of solar coronal holes, suggesting that information about the latitudinal structure of solar wind stream sources propagates to these distances.

  6. Large Range Manipulation of Exciton Species in Monolayer WS2

    CERN Document Server

    Wei, Ke; Yang, Hang; Cheng, Xiangai; Jiang, Tian

    2016-01-01

    Unconventional emissions from exciton and trion in monolayer WS2 are studied by photoexcitation. Excited by 532nm laser beam, the carrier species in the monolayer WS2 are affected by the excess electrons escaping from photoionization of donor impurity, the concentration of which varies with different locations of the sample. Simply increasing the excitation power at room temperature, the excess electron and thus the intensity ratio of excited trion and exciton can be continuously tuned over a large range from 0.1 to 7.7. Furthermore, this intensity ratio can also be manipulated by varying temperature. However, in this way the resonance energy of the exciton and trion show red-shifts with increasing temperature due to electron-phonon coupling. The binding energy of the trion is determined to be ~23meV and independent to temperature, indicating strong Coulomb interaction of carriers in such 2D materials.

  7. Beta-decay study of $T_z=-2$ proton-rich nucleus $^{20}$Mg

    CERN Document Server

    Sun, L J; Lin, C J; Wang, J S; Fang, D Q; Li, Z H; Wang, Y T; Li, J; Yang, L; Ma, N R; Wang, K; Zang, H L; Wang, H W; Li, C; Shi, C Z; Nie, M W; Li, X F; Li, H; Ma, J B; Ma, P; Jin, S L; Huang, M R; Bai, Z; Wang, J G; Yang, F; Jia, H M; Zhang, H Q; Liu, Z H; Bao, P F; Wang, D X; Ma, Y G; Yang, Y Y; Zhou, Y J; Ma, W H; Chen, J

    2016-01-01

    The $\\beta$ decay of the drip-line nucleus $^{20}$Mg gives important information on resonances in $^{20}$Na, which are relevant for the astrophysical $rp$-process. A detailed $\\beta$ decay spectroscopic study of $^{20}$Mg was performed by a continuous-implantation method. A detection system was specially developed for charged-particle decay studies, giving improved spectroscopic information including the half-life of $^{20}$Mg, the excitation energies, the branching ratios, and the log $ft$ values for the states in $^{20}$Na populated in the $\\beta$ decay of $^{20}$Mg. A new proton branch was observed and the corresponding excited state in $^{20}$Na was proposed. The large isospin asymmetry for the mirror decays of $^{20}$Mg and $^{20}$O was reproduced, as well. However, no conclusive conclusion can be draw about the astrophysically interesting 2645~keV resonance in $^{20}$Na due to the limited statistics.

  8. Er Web 2.0 klar til mainstream?

    DEFF Research Database (Denmark)

    Ivang, Reimer

    2009-01-01

    BLOG: Spørgsmålene der relateres til Web 2.0 er mange. Men en af de mest signifikante er om netop din virksomhed skal anvende Web 2.0 teknologier? Hvad kan I få ud af det?......BLOG: Spørgsmålene der relateres til Web 2.0 er mange. Men en af de mest signifikante er om netop din virksomhed skal anvende Web 2.0 teknologier? Hvad kan I få ud af det?...

  9. Pathology in the era of Web 2.0.

    Science.gov (United States)

    Schreiber, William E; Giustini, Dean M

    2009-12-01

    In the past few years, the term Web 2.0 has become a descriptor for the increased functionality of Web sites, including those with medical content. Most physicians do not know what Web 2.0 means or how it can impact their work lives. This review provides some background on the evolution of Web 2.0 and describes how its features are being incorporated into medical Web sites. Some potential applications of Web 2.0 in pathology and laboratory medicine are discussed, as are the issues that must be considered when adopting this new technology.

  10. OAuth 2.0 identity and access management patterns

    CERN Document Server

    Spasovski, Martin

    2013-01-01

    This is a practical and fast-paced guide that gives you all the information you need to start implementing secure OAuth 2.0 implementations in your web applications.OAuth 2.0 Identity and Access Management Patterns is intended for software developers, software architects, and enthusiasts working with the OAuth 2.0 framework.In order to learn and understand the OAuth 2.0 grant flow, it is assumed that you have some basic knowledge of HTTP communication. For the practical examples, basic knowledge of HTML templating, programming languages, and executing commands in the command line terminal is a

  11. LIBRARY 2.0 TIDAK TERASA ADA DI SEKITAR KITA

    Directory of Open Access Journals (Sweden)

    Rosa Widyawan

    2012-07-01

    Full Text Available This essay reveals application of Web 2.0 tools in some Indonesia university, academic, and special libraries. It is an explorative preliminary study, and this literature based article is a starting effort to conduct a more comprehensive research in this subject. Fifteen library web pages are examined to identify their application of Web 2.0 tools. It finds out that some of them use such tool, but they seem not really aware the advantages of Web 2.0 for their libraries. This essay suggest that the implementation of Web 2.0 tools should be supported by decission makers.

  12. Er Web 2.0 klar til mainstream?

    DEFF Research Database (Denmark)

    Ivang, Reimer

    2009-01-01

    BLOG: Spørgsmålene der relateres til Web 2.0 er mange. Men en af de mest signifikante er om netop din virksomhed skal anvende Web 2.0 teknologier? Hvad kan I få ud af det?......BLOG: Spørgsmålene der relateres til Web 2.0 er mange. Men en af de mest signifikante er om netop din virksomhed skal anvende Web 2.0 teknologier? Hvad kan I få ud af det?...

  13. Web 2.0 for social learning in higher education

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh

    2011-01-01

    The use of Web 2.0 in higher education provides for a number of different possibilities. In this paper we look into the use of Web 2.0 as a platform for social learning supplementing traditional teaching methods such as lectures and on place group work. The findings are astonishing revealing...... challenges such as the unknown genre of Web 2.0 for learning and changed behaviors with relevance for the identity creation and perception of others. The insight points to a number of issues of relevance when Web 2.0 is integrated in design for learning....

  14. A New Population of Compton-Thick AGN Identified Using the Spectral Curvature Above 10 keV

    CERN Document Server

    Koss, Michael J; Balokovic, M; Stern, D; Gandhi, P; Lamperti, I; Alexander, D M; Ballantyne, D R; Bauer, F E; Berney, S; Brandt, W N; Comastri, A; Gehrels, N; Harrison, F A; Lansbury, G; Markwardt, C; Ricci, C; Rivers, E; Schawinski, K; Treister, E; Urry, C Megan

    2016-01-01

    We present a new metric that uses the spectral curvature (SC) above 10 keV to identify Compton-thick AGN in low-quality Swift BAT X-ray data. Using NuSTAR, we observe nine high SC-selected AGN. We find that high-sensitivity spectra show the majority are Compton-thick (78% or 7/9) and the remaining two are nearly Compton-thick (NH~5-8x10^23 cm^-2). We find the SC_bat and SC_nustar measurements are consistent, suggesting this technique can be applied to future telescopes. We tested the SC method on well-known Compton-thick AGN and find it is much more effective than broad band ratios (e.g. 100% using SC vs. 20% using 8-24/3-8 keV). Our results suggest that using the >10 keV emission may be the only way to identify this population since only two sources show Compton-thick levels of excess in the OIII to X-ray emission ratio (F_OIII/F_2-10 keV>1) and WISE colors do not identify most of them as AGN. Based on this small sample, we find that a higher fraction of these AGN are in the final merger stage than typical B...

  15. Health 2.0 and implications for nursing education.

    Science.gov (United States)

    Nelson, Ramona

    2012-01-01

    Over the last 20 years the evolution of web browsers providing easy access to the Internet has initiated a revolution in access to healthcare related information for both healthcare providers and patients. This access has changed both the process used to deliver education and the content of the nursing education curriculum worldwide. Our amazing ability to access information around the world is referred as to Web 1.0. Web 2.0 moves beyond access to a world where users are interactively creating information. With the advent of Health 2.0 we are confronting a second revolution that is challenging all aspects of healthcare including all aspects of nursing. This paper explores the concept of Health 2.0, discusses a conceptual framework approach for integrating Health 2.0 content into the nursing curriculum, outlines examples of key concepts required in today's nursing curriculum and identifies selected issues arising from the impact of Health 2.0.

  16. SNR 1E 0102.2-7219 as an X-ray calibration standard in the 0.5-1.0 keV bandpass and its application to the CCD instruments aboard Chandra, Suzaku, Swift and XMM-Newton

    Science.gov (United States)

    Plucinsky, Paul P.; Beardmore, Andrew P.; Foster, Adam; Haberl, Frank; Miller, Eric D.; Pollock, Andrew M. T.; Sembay, Steve

    2017-01-01

    Context. The flight calibration of the spectral response of charge-coupled device (CCD) instruments below 1.5 keV is difficult in general because of the lack of strong lines in the on-board calibration sources typically available. This calibration is also a function of time due to the effects of radiation damage on the CCDs and/or the accumulation of a contamination layer on the filters or CCDs. Aims: We desire a simple comparison of the absolute effective areas of the current generation of CCD instruments onboard the following observatories: Chandra ACIS-S3, XMM-Newton (EPIC-MOS and EPIC-pn), Suzaku XIS, and Swift XRT and a straightforward comparison of the time-dependent response of these instruments across their respective mission lifetimes. Methods: We have been using 1E 0102.2-7219, the brightest supernova remnant in the Small Magellanic Cloud, to evaluate and modify the response models of these instruments. 1E 0102.2-7219 has strong lines of O, Ne, and Mg below 1.5 keV and little or no Fe emission to complicate the spectrum. The spectrum of 1E 0102.2-7219 has been well-characterized using the RGS gratings instrument on XMM-Newton and the HETG gratings instrument on Chandra. As part of the activities of the International Astronomical Consortium for High Energy Calibration (IACHEC), we have developed a standard spectral model for 1E 0102.2-7219 and fit this model to the spectra extracted from the CCD instruments. The model is empirical in that it includes Gaussians for the identified lines, an absorption component in the Galaxy, another absorption component in the SMC, and two thermal continuum components with different temperatures. In our fits, the model is highly constrained in that only the normalizations of the four brightest lines/line complexes (the O vii Heα triplet, O viii Lyα line, the Ne ix Heα triplet, and the Ne x Lyα line) and an overall normalization are allowed to vary, while all other components are fixed. We adopted this approach to

  17. Using Web 2.0 for health promotion and social marketing efforts: lessons learned from Web 2.0 experts.

    Science.gov (United States)

    Dooley, Jennifer Allyson; Jones, Sandra C; Iverson, Don

    2014-01-01

    Web 2.0 experts working in social marketing participated in qualitative in-depth interviews. The research aimed to document the current state of Web 2.0 practice. Perceived strengths (such as the viral nature of Web 2.0) and weaknesses (such as the time consuming effort it took to learn new Web 2.0 platforms) existed when using Web 2.0 platforms for campaigns. Lessons learned were identified--namely, suggestions for engaging in specific types of content creation strategies (such as plain language and transparent communication practices). Findings present originality and value to practitioners working in social marketing who want to effectively use Web 2.0.

  18. Design and Operational Experience of a Microwave Cavity Axion Detector for the 20-100 micro-eV Range

    CERN Document Server

    Kenany, S Al; Backes, K M; Brubaker, B M; Cahn, S B; Carosi, G; Gurevich, Y V; Kindel, W F; Lamoreaux, S K; Lehnert, K W; Lewis, S M; Malnou, M; Palken, D A; Rapidis, N M; Root, J R; Simanovskaia, M; Shokair, T M; Urdinaran, I; van Bibber, K A; Zhong, L

    2016-01-01

    We describe a dark matter axion detector designed, constructed, and operated both as an innovation platform for new cavity and amplifier technologies and as a data pathfinder in the $5 - 25$ GHz range ($\\sim20-100\\: \\mu$eV). The platform is small but flexible to facilitate the development of new microwave cavity and amplifier concepts in an operational environment. The experiment has recently completed its first data production; it is the first microwave cavity axion search to deploy a Josephson parametric amplifier and a dilution refrigerator to achieve near-quantum limited performance.

  19. An electrically driven terahertz metamaterial diffractive modulator with more than 20 dB of dynamic range

    Energy Technology Data Exchange (ETDEWEB)

    Karl, N.; Reichel, K.; Mendis, R.; Mittleman, D. M. [Department of Electrical and Computer Engineering, Rice University, MS 378, Houston, Texas 77251-1892 (United States); Chen, H.-T.; Taylor, A. J. [Center for Integrated Nanotechnologies, Los Alamos National Laboratory, P. O. Box 1663, MS K771, Los Alamos, New Mexico 87545 (United States); Brener, I.; Benz, A.; Reno, J. L. [Center for Integrated Nanotechnologies, Sandia National Laboratories, P. O. Box 5800, MS 1082, Albuquerque, New Mexico 87185 (United States)

    2014-03-03

    We design and experimentally demonstrate a switchable diffraction grating for terahertz modulation based on planar active metamaterials, where a Schottky gate structure is implemented to tune the metamaterial resonances in real-time via the application of an external voltage bias. The diffraction grating is formed by grouping the active split-ring resonators into an array of independent columns with alternate columns biased. We observe off-axis diffraction over a wide frequency band in contrast to the narrow-band resonances, which permits operation of the device as a relatively high-speed, wide-bandwidth, high-contrast modulator, with more than 20 dB of dynamic range.

  20. Design and operational experience of a microwave cavity axion detector for the 20 - 100 μeV range

    Science.gov (United States)

    Al Kenany, S.; Anil, M. A.; Backes, K. M.; Brubaker, B. M.; Cahn, S. B.; Carosi, G.; Gurevich, Y. V.; Kindel, W. F.; Lamoreaux, S. K.; Lehnert, K. W.; Lewis, S. M.; Malnou, M.; Palken, D. A.; Rapidis, N. M.; Root, J. R.; Simanovskaia, M.; Shokair, T. M.; Urdinaran, I.; van Bibber, K. A.; Zhong, L.

    2017-05-01

    We describe a dark matter axion detector designed, constructed, and operated both as an innovation platform for new cavity and amplifier technologies and as a data pathfinder in the 5-25 GHz range (∼ 20 - 100 μeV) . The platform is small but flexible to facilitate the development of new microwave cavity and amplifier concepts in an operational environment. The experiment has recently completed its first data production; it is the first microwave cavity axion search to deploy a Josephson parametric amplifier and a dilution refrigerator to achieve near-quantum limited performance.

  1. Learning Based on Web2.0%基于Web2.0的学习

    Institute of Scientific and Technical Information of China (English)

    马金凤

    2011-01-01

    对基于Web 2.0的学习进行了论述。通过分析Web 2.0的模式和特征,探讨了Web 2.0在教学过程中对于教师和学习者产生的新的教学、学习方式,考察了Web 2.0对于学习资源进行的知识管理,提出了在Web 2.0学习中对学习者生存能力和道德规范的要求。%this article mainly based on Web 2.0 learning to recognize.Through the analysis of Web 2.0 patterns and characteristics,discusses the Web 2.0 in the teaching process on teachers and learners new teaching and learning mode,inspects the Web 2.0 for learning

  2. Primary Discussions of e-Learning 2.0%e-Learning 2.0初探

    Institute of Scientific and Technical Information of China (English)

    刘革平; 李倩

    2009-01-01

    理论与技术的进步给e-Learning带来了发展和变革的机会.本文在阐述Web 2.0与e-Learning关系的基础上引入了e-Learning 2.0的概念.文中讨论了e-Learning 2.0的本质特征并给出了其含义的界定.最后论述了e-Learning 2.0的理论基础.

  3. New and Innovative Library Services: Moving with Web 2.0 / Library 2.0 Technology, a Case Study

    Science.gov (United States)

    Sahu, H. K.; Pathak, S. K.; Singh, S. N.

    2010-10-01

    We give an overview and definition of Web 2.0 and Library 2.0 technology, especially addressing how it changes access to collections for users. We also describe its unlimited possibilities. The various components of Library 2.0 viz blogs, wikis, RSS, instant messaging, social networking, podcasting, and tagging are briefly summarized. Initiatives at three special information centers and libraries (IUCAA — Astronomy and Astrophysics; IIT — Science and Technology; and NIV — Viral Diseases) are described. We conclude with a futuristic view of Library 2.0.

  4. SNR 1E 0102.2-7219 as an X-ray Calibration Standard in the 0.5-1.0 keV Bandpass and Its Application to the CCD Instruments aboard Chandra, Suzaku, Swift and XMM-Newton

    CERN Document Server

    Plucinsky, Paul P; Foster, Adam; Haberl, Frank; Miller, Eric D; Pollock, A M T; Sembay, Steve

    2016-01-01

    We desire a simple comparison of the absolute effective areas of the current generation of CCD instruments onboard the following observatories: Chandra ACIS-S3, XMM-Newton (EPIC-MOS and EPIC-pn), Suzaku XIS, and Swift XRT and a straightforward comparison of the time-dependent response of these instruments across their respective mission lifetimes. We have been using 1E 0102.2-7219, the brightest supernova remnant in the Small Magellanic Cloud, to evaluate and modify the response models of these instruments. 1E 0102.2-7219 has strong lines of O, Ne, and Mg below 1.5 keV and little or no Fe emission to complicate the spectrum. As part of the activities of the International Astronomical Consortium for High Energy Calibration (IACHEC), we have developed a standard spectral model for 1E 0102.2-7219. The model is empirical in that it includes Gaussians for the identified lines, an absorption component in the Galaxy, another absorption component in the SMC, and two thermal continuum components. In our fits, the mode...

  5. A Framework for Web 2.0 Learning Design

    Science.gov (United States)

    Bower, Matt; Hedberg, John G.; Kuswara, Andreas

    2010-01-01

    This paper describes an approach to conceptualising and performing Web 2.0-enabled learning design. Based on the Technological, Pedagogical and Content Knowledge model of educational practice, the approach conceptualises Web 2.0 learning design by relating Anderson and Krathwohl's Taxonomy of Learning, Teaching and Assessing, and different types…

  6. Culture, Learning Styles, and Web 2.0

    Science.gov (United States)

    Olaniran, Bolanle A.

    2009-01-01

    This article explores Web 2.0 in interactive learning environments. Specifically, the article examines Web 2.0 as an interactive learning platform that holds potential, but is also limited by learning styles and cultural value preferences. The article explores the issue of control from both teacher and learner perspectives, and in particular the…

  7. On Recommending Web 2.0 Tools to Personalise Learning

    Science.gov (United States)

    Juškeviciene, Anita; Kurilovas, Eugenijus

    2014-01-01

    The paper aims to present research results on using Web 2.0 tools for learning personalisation. In the work, personalised Web 2.0 tools selection method is presented. This method takes into account student's learning preferences for content and communication modes tailored to the learning activities with a view to help the learner to quickly and…

  8. Information Literacy Instruction in the Web 2.0 Library

    Science.gov (United States)

    Humrickhouse, Elizabeth

    2011-01-01

    This paper examines how library educators can implement Web 2.0 tools in their Information Literacy programs to better prepare students for the rigors of academic research. Additionally, this paper looks at transliteracy and constructivism as the most useful teaching methods in a Web 2.0 classroom and attempts to pinpoint specific educational…

  9. The use of Web 2.0 technologies.

    Science.gov (United States)

    Kohtz, Cindy; Gowda, Connie; Stockert, Patricia; White, Jane; Kennel, Lynn

    2012-01-01

    Although many publications laud the potential benefits of using Web 2.0 technologies in nursing education, little has been published on the extent of their use. This descriptive study examined the personal and academic use of Web 2.0 technologies among nursing students enrolled in 3 different baccalaureate programs.

  10. Web 2.0 in the Mathematics Classroom

    Science.gov (United States)

    McCoy, Leah P.

    2014-01-01

    A key characteristic of successful mathematics teachers is that they are able to provide varied activities that promote student learning and assessment. Web 2.0 applications can provide an assortment of tools to help produce creative activities. A Web 2.0 tool enables the student to enter data and create multimedia products using text, graphics,…

  11. Government 2.0: key challenges to its realization

    NARCIS (Netherlands)

    Meijer, Albert Jacob; Koops, Bert-Jaap; Pieterson, Willem Jan; Overman, Sjors; ten Tije, Sanne

    2012-01-01

    Government 2.0 is often presented as a means to reinforce the relation between state and citizens in an information age. The promise of Government 2.0 is impressive but its potential has not or hardly been realized yet in practice. This paper uses insights from various disciplines to understand

  12. Web 2.0 in Dutch Higher Education

    NARCIS (Netherlands)

    Westera, Wim

    2009-01-01

    Westera, W. (2008). Web 2.0 in Dutch Higher Education. In J. Armstrong & T. Franklin (Eds.), A Review of Current and Developing International Practice in the Use of Social Networking (Web 2.0) in Higher Education (pp. 61-71). Bristol: Clex.

  13. Web 2.0.: Conceptual foundations and Marketing Issues

    NARCIS (Netherlands)

    Constantinides, Efthymios; Fountain, Stefan J.

    2008-01-01

    This paper identifies the technological and commercial foundations of the new category of online applications commonly described as Web 2.0 or Social Media. It examines the relevance of Web 2.0 for Marketing Strategy and for Direct Marketing in particular. The issue is not a clear-cut one: while

  14. NOAA-CIRES 20th Century Reanalysis (V2c)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 20th Century Reanalysis version 2c (20CRV2c)is an effort led by PSD and the CIRES at the University of Colorado to produce a reanalysis dataset spanning the...

  15. Web 2.0.: Conceptual foundations and Marketing Issues

    NARCIS (Netherlands)

    Constantinides, Efthymios; Fountain, Stefan J.

    2008-01-01

    This paper identifies the technological and commercial foundations of the new category of online applications commonly described as Web 2.0 or Social Media. It examines the relevance of Web 2.0 for Marketing Strategy and for Direct Marketing in particular. The issue is not a clear-cut one: while sev

  16. Web 2.0 Strategy in Libraries and Information Services

    Science.gov (United States)

    Byrne, Alex

    2008-01-01

    Web 2.0 challenges libraries to change from their predominantly centralised service models with integrated library management systems at the hub. Implementation of Web 2.0 technologies and the accompanying attitudinal shifts will demand reconceptualisation of the nature of library and information service around a dynamic, ever changing, networked,…

  17. A Framework for Web 2.0 Learning Design

    Science.gov (United States)

    Bower, Matt; Hedberg, John G.; Kuswara, Andreas

    2010-01-01

    This paper describes an approach to conceptualising and performing Web 2.0-enabled learning design. Based on the Technological, Pedagogical and Content Knowledge model of educational practice, the approach conceptualises Web 2.0 learning design by relating Anderson and Krathwohl's Taxonomy of Learning, Teaching and Assessing, and different types…

  18. Leadership 2.0: Social Media in Advocacy

    Science.gov (United States)

    Gonzales, Lisa; Vodicka, Devin; White, John

    2011-01-01

    Technology is always changing, always improving, and always pushing the envelope for how one works in education. In this increasingly connected age, people have seen rapid growth in social network tools such as Twitter and Facebook. These sites are representative of Web 2.0 resources where users contribute content. Other examples of Web 2.0 sites…

  19. Web 2.0: Conceptual foundations and marketing issues

    NARCIS (Netherlands)

    Constantinides, Efthymios; Fountain, Stefan J.

    2008-01-01

    This paper identifies the technological and commercial foundations of the new category of online applications commonly described as Web 2.0 or Social Media. It examines the relevance of Web 2.0 for Marketing Strategy and for Direct Marketing in particular. The issue is not a clear-cut one: while sev

  20. Towards Volitional Media Literacy through Web 2.0

    Science.gov (United States)

    Kynaslahti, Heikki; Vesterinen, Olli; Lipponen, Lasse; Vahtivuori-Hanninen, Sanna; Tella, Seppo

    2008-01-01

    The authors discuss the results of a study in which they investigated 68 university-level media education students' knowledge of Web 2.0 and their conceptions about its impact on media literacy. The main research finding was that the students argued firmly in favor of new media literacy. Their own use of Web 2.0 applications was, however, rather…

  1. Web 2.0: Creating a Classroom without Walls

    Science.gov (United States)

    Barlow, Tim

    2008-01-01

    This article is about my year-long journey implementing Web 2.0 tools into my teaching practice. The goal throughout my journey has always been to increase my students' intrinsic motivation to learn about science. The Web 2.0 tools I used along my journey were weblogs (blogs) and podcasts. (Contains 1 figure.)

  2. NOAA-CIRES 20th Century Reanalysis (V2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 20th Century Reanalysis version 2 (20CRV2)is an effort led by PSD and the CIRES at the University of Colorado to produce a reanalysis dataset spanning the entire...

  3. How to use web 2.0 in your library

    CERN Document Server

    Bradley, Phil

    2007-01-01

    The Web 2.0 and social software explosion has the capability to transform the online profile of libraries and help reach out to tech-savvy young users to whom the library may be invisible. This title explains how to use the different types of Web 2.0 technologies, and, using examples, shows how libraries can get the most out of them.

  4. Search for 511 keV emission in satellite galaxies of the Milky Way with INTEGRAL/SPI

    Science.gov (United States)

    Siegert, Thomas; Diehl, Roland; Vincent, Aaron C.; Guglielmetti, Fabrizia; Krause, Martin G. H.; Boehm, Celine

    2016-10-01

    Context. The positron (e+) annihilation γ-ray signal in the Milky Way (MW) shows a puzzling morphology: a very bright bulge and a very low surface-brightness disk. A coherent explanation of the e+ origin, propagation through the Galaxy and subsequent annihilation in the interstellar medium has not yet been found. Tentative explanations involve e+s from radioactivity, X-ray binaries, and dark matter (DM). Aims: Dwarf satellite galaxies (DSGs) are believed to be dominated by DM and hence are promising candidates in the search for 511 keV emission as a result of DM annihilation into e+e--pairs. The goal of this study is to constrain possible 511 keV γ-ray signals from 39 DSGs of the MW and to test the annihilating DM scenario. Methods: We used the spectrometer SPI on INTEGRAL to extract individual spectra for the studied objects in the range 490-530 keV. As the diffuse galactic 511 keV emission dominates the overall signal, we modelled the large-scale morphology of the MW accordingly and included this in a maximum likelihood analysis. Alternatively, a distance-weighted stacked spectrum was determined, representing an average DSG seen in 511 keV. Results: Only Reticulum II (Ret II) shows a 3.1σ signal. Five other sources show tentative 2σ signals. The ratio of mass to 511 keV luminosity, Υ511, shows a marginal trend towards higher values for intrinsically brighter objects in contrast to the mass-to-light ratio, ΥV in the V band, which is generally used to uncover DM in DSGs. Conclusions: All derived 511 keV flux values or upper limits are above the flux level implied by a DM interpretation of the MW bulge signal. The signal detected from Ret II is unlikely to be related to a DM origin alone, otherwise, the MW bulge would be ~100 times brighter in 511 keV than what is seen with SPI. Ret II is exceptional considering the DSG sample and rather points to enhanced recent star formation activity if its origins are similar to processes in the MW. Understanding this

  5. Sensitivity to BST-2 restriction correlates with Orthobunyavirus host range.

    Science.gov (United States)

    Varela, Mariana; Piras, Ilaria M; Mullan, Catrina; Shi, Xiaohong; Tilston-Lunel, Natasha L; Pinto, Rute Maria; Taggart, Aislynn; Welch, Stephen R; Neil, Stuart J D; Kreher, Felix; Elliott, Richard M; Palmarini, Massimo

    2017-09-01

    Orthobunyaviruses include several recently emerging viruses of significant medical and veterinary importance. There is currently very limited understanding on what determines the host species range of these pathogens. In this study we discovered that BST-2/tetherin restricts orthobunyavirus replication in a host-specific manner. We show that viruses with human tropism (Oropouche virus and La Crosse virus) are restricted by sheep BST-2 but not by the human orthologue, while viruses with ruminant tropism (Schmallenberg virus and others) are restricted by human BST-2 but not by the sheep orthologue. We also show that BST-2 blocks orthobunyaviruses replication by reducing the amount of envelope glycoprotein into viral particles egressing from infected cells. This is the first study identifying a restriction factor that correlates with species susceptibility to orthobunyavirus infection. This work provides insight to help us dissect the adaptive changes that bunyaviruses require to cross the species barrier and emerge into new species. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Combining 2-m temperature nowcasting and short range ensemble forecasting

    Directory of Open Access Journals (Sweden)

    A. Kann

    2011-12-01

    Full Text Available During recent years, numerical ensemble prediction systems have become an important tool for estimating the uncertainties of dynamical and physical processes as represented in numerical weather models. The latest generation of limited area ensemble prediction systems (LAM-EPSs allows for probabilistic forecasts at high resolution in both space and time. However, these systems still suffer from systematic deficiencies. Especially for nowcasting (0–6 h applications the ensemble spread is smaller than the actual forecast error. This paper tries to generate probabilistic short range 2-m temperature forecasts by combining a state-of-the-art nowcasting method and a limited area ensemble system, and compares the results with statistical methods. The Integrated Nowcasting Through Comprehensive Analysis (INCA system, which has been in operation at the Central Institute for Meteorology and Geodynamics (ZAMG since 2006 (Haiden et al., 2011, provides short range deterministic forecasts at high temporal (15 min–60 min and spatial (1 km resolution. An INCA Ensemble (INCA-EPS of 2-m temperature forecasts is constructed by applying a dynamical approach, a statistical approach, and a combined dynamic-statistical method. The dynamical method takes uncertainty information (i.e. ensemble variance from the operational limited area ensemble system ALADIN-LAEF (Aire Limitée Adaptation Dynamique Développement InterNational Limited Area Ensemble Forecasting which is running operationally at ZAMG (Wang et al., 2011. The purely statistical method assumes a well-calibrated spread-skill relation and applies ensemble spread according to the skill of the INCA forecast of the most recent past. The combined dynamic-statistical approach adapts the ensemble variance gained from ALADIN-LAEF with non-homogeneous Gaussian regression (NGR which yields a statistical mbox{correction} of the first and second moment (mean bias and dispersion for Gaussian distributed continuous

  7. Total bremsstrahlung spectra of thick lead compounds produced by {sup 90}Sr beta emitter in photon energy region of 10–100 keV

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Suhansar Jit [Department of Physics, B.B.S.B Polytechnic, Fatehgarh Sahib, Punjab (India); Singh, Tajinder, E-mail: tajindersingh2k9@gmail.com [Department of Physics, Mata Gujri College, Fatehgarh Sahib, Punjab (India); Singh, Doordarshi [Department of Mechanical Engineering, B.B.S.B Engineering College, Fatehgarh Sahib, Punjab (India); Singh, Amrit [Department of Physics, Baba Ajay Singh Khalsa College, Gurdas Nangal, Gurdaspur, Punjab (India); Dhaliwal, A.S. [Department of Physics, Sant Longowal Institute of Engineering & Technology, Longowal (Sangrur), Punjab (India)

    2017-06-15

    Highlights: • Total bremsstrahlung spectra in thick targets of Pb compounds by {sup 90}Sr in energy range 10–100 keV. • Experimental results show better agreement with the model which includes PB in SA up to 30 keV. • At higher photon energy region 30–100 keV the model which describes OB is more accurate. • Experimental results show positive deviations from the entire models at higher energy end spectrum. - Abstract: The total bremsstrahlung spectra in the thick targets of lead acetate trihydrate (Pb(CH{sub 3}COO){sub 2}·3H{sub 2}O), lead nitrate Pb(NO{sub 3}){sub 2} and lead chloride (PbCl{sub 2}) produced by {sup 90}Sr beta particles have been investigated in the photon energy region of 10–100 keV. The experimental bremsstrahlung spectra have been compared with the theoretical models Elwert corrected (non relativistic) Bethe Heitler theory, modified Elwert factor (relativistic) Bethe Heitler theory for ordinary bremsstrahlung and modified Elwert factor (relativistic) Bethe Heitler theory which includes polarization bremsstrahlung in the stripped atom approximation. The experimental results show better agreement with theoretical model that includes polarization bremsstrahlung in stripped approximation in the photon energy region below 30 keV. However, at higher photon energy region 30–100 keV, the theoretical model which describes ordinary bremsstrahlung is more accurate to describe the experimental bremsstrahlung spectra. The experimental results show positive deviations from the entire theoretical models at higher energy end of the spectrum. The results indicate that polarization bremsstrahlung plays important role in the formation of total bremsstrahlung spectra in lead compounds produced by continuous beta particles at low photon energy region of 10–30 keV.

  8. Mobile 2.0带动的革新

    Institute of Scientific and Technical Information of China (English)

    张雪超

    2010-01-01

    @@ Mobile 2.0并不是一个陌生的概念,但很多人仅仅是将Mobile 2.0视为Web 2.0的伴生品,是Web 2.0延伸出的移动版本. 2005年,Tim O'Reilly提出的Web 2.0理论席卷了全球的互联网,一股创新风暴将互联网带到了一个新的发展阶段,Blog、RSS、SNS、Wiki等应用和服务迅速得到了人们的青睐,并逐渐将人们带入了一个数字化生活的时代.

  9. Enabling Problem Based Learning through Web 2.0 Technologies

    DEFF Research Database (Denmark)

    Tambouris, Efthimios; Panopoulou, Eleni; Tarabanis, Konstantinos

    2012-01-01

    of modern educational systems. Established pedagogical strategies, such as Problem Based Learning (PBL), are being adapted for online use in conjunction with modern Web 2.0 technologies and tools. However, even though Web 2.0 and progressive social-networking technologies are automatically associated...... with ideals such as collaboration, sharing, and active learning, it is also possible to use them in a very conservative, teacher-centred way limiting thus their impact. In this paper, we present a PBL 2.0 framework, i.e., a framework combining PBL practices with Web 2.0 technologies. More specifically, we (a......Advances in Information and Communications Technology (ICT), particularly the so-called Web 2.0, are affecting all aspects of our life: how we communicate, how we shop, how we socialise, and how we learn. Facilitating learning through the use of ICT, also known as eLearning, is a vital part...

  10. Driving Web 2.0 Tool Adoption in Agricultural Education

    Directory of Open Access Journals (Sweden)

    Constantina Costopouloul

    2013-04-01

    Full Text Available The new opportunities for collaboration, participatory content creation and communication offered through the advancements of Web 2.0, such as social networking, blogs, wikis, video sharing and other, are creating new learning models. In turn, tutors cannot ignore this trend and have to bear the responsibility of incorporating Web 2.0 tools in formal, informal, work-based and vocational education and approach their students in a very familiar and favourable way. In this context, this paper tries to highlight the need for enhancing tutors’ skills and drive Web 2.0 tool adoption in educational practice. Thus, it draws upon the successful example of a European project regarding agricultural tutors’ training on Web 2.0 tools. The challenge for all agricultural tutors is how to integrate Web 2.0 tools into current curricula and education.

  11. The T2K Side Muon Range Detector (SMRD)

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, S. [Kobe University, Department of Physics (Japan); Barr, G. [University of Oxford, Department of Physics, Oxford (United Kingdom); Batkiewicz, M.; Błocki, J. [H. Niewodniczański Institute of Nuclear Physics PAN, Kraków (Poland); Brinson, J.D.; Coleman, W. [Louisiana State University, Department of Physics and Astronomy, Baton Rouge, LA (United States); Dąbrowska, A. [H. Niewodniczański Institute of Nuclear Physics PAN, Kraków (Poland); Danko, I. [University of Pittsburgh, Department of Physics and Astronomy, Pittsburgh, PA (United States); Dziewiecki, M. [Warsaw University of Technology, Institute of Radioelectronics, Warsaw (Poland); Ellison, B. [Louisiana State University, Department of Physics and Astronomy, Baton Rouge, LA (United States); Golyshkin, L. [Institute for Nuclear Research, Moscow (Russian Federation); Gould, R. [Louisiana State University, Department of Physics and Astronomy, Baton Rouge, LA (United States); Hara, T. [Kobe University, Department of Physics (Japan); Haremza, J.; Hartfiel, B. [Louisiana State University, Department of Physics and Astronomy, Baton Rouge, LA (United States); Holeczek, J. [University of Silesia, Institute of Physics, Katowice (Poland); Izmaylov, A.; Khabibullin, M.; Khotjantsev, A. [Institute for Nuclear Research, Moscow (Russian Federation); Kiełczewska, D. [University of Warsaw, Institute of Experimental Physics, Warsaw (Poland); and others

    2013-01-11

    The T2K experiment is a long baseline neutrino oscillation experiment aiming to observe the appearance of ν{sub e} in a ν{sub μ} beam. The ν{sub μ} beam is produced at the Japan Proton Accelerator Research Complex (J-PARC), observed with the 295 km distant Super-Kamiokande Detector and monitored by a suite of near detectors at 280 m from the proton target. The near detectors include a magnetized off-axis detector (ND280) which measures the unoscillated neutrino flux and neutrino cross-sections. The present paper describes the outermost component of ND280 which is a Side Muon Range Detector (SMRD) composed of scintillation counters with embedded wavelength shifting fibers and Multi-Pixel Photon Counter readout. The components, performance and response of the SMRD are presented.

  12. Elevation-dependent temperature trends in the Rocky Mountain Front Range: changes over a 56- and 20-year record.

    Directory of Open Access Journals (Sweden)

    Chris R McGuire

    Full Text Available Determining the magnitude of climate change patterns across elevational gradients is essential for an improved understanding of broader climate change patterns and for predicting hydrologic and ecosystem changes. We present temperature trends from five long-term weather stations along a 2077-meter elevational transect in the Rocky Mountain Front Range of Colorado, USA. These trends were measured over two time periods: a full 56-year record (1953-2008 and a shorter 20-year (1989-2008 record representing a period of widely reported accelerating change. The rate of change of biological indicators, season length and accumulated growing-degree days, were also measured over the 56 and 20-year records. Finally, we compared how well interpolated Parameter-elevation Regression on Independent Slopes Model (PRISM datasets match the quality controlled and weather data from each station. Our results show that warming signals were strongest at mid-elevations over both temporal scales. Over the 56-year record, most sites show warming occurring largely through increases in maximum temperatures, while the 20-year record documents warming associated with increases in maximum temperatures at lower elevations and increases in minimum temperatures at higher elevations. Recent decades have also shown a shift from warming during springtime to warming in July and November. Warming along the gradient has contributed to increases in growing-degree days, although to differing degrees, over both temporal scales. However, the length of the growing season has remained unchanged. Finally, the actual and the PRISM interpolated yearly rates rarely showed strong correlations and suggest different warming and cooling trends at most sites. Interpretation of climate trends and their seasonal biases in the Rocky Mountain Front Range are dependent on both elevation and the temporal scale of analysis. Given mismatches between interpolated data and the directly measured station data

  13. IONIZATION AND FRAGMENTATION OF ANTHRACENE UPON INTERACTION WITH keV PROTONS AND alpha PARTICLES

    NARCIS (Netherlands)

    Postma, J.; Bari, S.; Hoekstra, R.; Tielens, A. G. G. M.; Schlathoelter, T.

    2010-01-01

    The interaction of keV ions with polyaromatic hydrocarbons is dominated by charge exchange and electronic stopping. We have studied the response of the polyaromatic hydrocarbon anthracene (C(14)H(10)) upon keV H(+) and He(2+) impact using high-resolution time-of-flight mass spectrometry. Extensive f

  14. Enabling the transition towards Earth Observation Science 2.0

    Science.gov (United States)

    Mathieu, Pierre-Philippe; Desnos, Yves-Louis

    2015-04-01

    Science 2.0 refers to the rapid and systematic changes in doing Research and organising Science driven by the rapid advances in ICT and digital technologies combined with a growing demand to do Science for Society (actionable research) and in Society (co-design of knowledge). Nowadays, teams of researchers around the world can easily access a wide range of open data across disciplines and remotely process them on the Cloud, combining them with their own data to generate knowledge, develop information products for societal applications, and tackle complex integrative complex problems that could not be addressed a few years ago. Such rapid exchange of digital data is fostering a new world of data-intensive research, characterized by openness, transparency, and scrutiny and traceability of results, access to large volume of complex data, availability of community open tools, unprecedented level of computing power, and new collaboration among researchers and new actors such as citizen scientists. The EO scientific community is now facing the challenge of responding to this new paradigm in science 2.0 in order to make the most of the large volume of complex and diverse data delivered by the new generation of EO missions, and in particular the Sentinels. In this context, ESA - in particular within the framework of the Scientific Exploitation of Operational Missions (SEOM) element - is supporting a variety of activities in partnership with research communities to ease the transition and make the most of the data. These include the generation of new open tools and exploitation platforms, exploring new ways to exploit data on cloud-based platforms, dissiminate data, building new partnership with citizen scientists, and training the new generation of data scientists. The paper will give a brief overview of some of ESA activities aiming to facilitate the exploitation of large amount of data from EO missions in a collaborative, cross-disciplinary, and open way, from science to

  15. Oh! Web 2.0, Virtual Reference Service 2.0, Tools and Techniques (I): A Basic Approach

    Science.gov (United States)

    Arya, Harsh Bardhan; Mishra, J. K.

    2011-01-01

    This study targets librarians and information professionals who use Web 2.0 tools and applications with a view to providing snapshots on how Web 2.0 technologies are used. It also aims to identify values and impact that such tools have exerted on libraries and their services, as well as to detect various issues associated with the implementation…

  16. Usage Analysis of Web 2.0 and Library 2.0 Tools by Librarians in Kwara State Academic Libraries

    Science.gov (United States)

    Tella, Adeyinka; Soluoku, Taofeeqat

    2016-01-01

    This study analysed the usage of Web 2.0 and Library 2.0 tools by librarians in Kwara State academic libraries. A sample of 40 librarians was surveyed through total enumeration sampling technique from four different tertiary education institutions libraries in Kwara State, Nigeria. Questionnaire was used for the collection of data. The collected…

  17. European Union System for the Evaluation of Substances 2.0 (EUSES 2.0); background report

    NARCIS (Netherlands)

    Lijzen JPA; Rikken MGJ; LER; SEC

    2004-01-01

    This report describes the second version of the PC-program 'European Union System for the Evaluation of Substances', EUSES 2.0. It completely replaces the EUSES 1.0 program and documentation. EUSES 2.0 is designed to be a decision-support system for the evaluation of the risks of substances to man a

  18. Nustar and Chandra insight into the nature of the 3-40 kev nuclear emission in NGC 253

    DEFF Research Database (Denmark)

    Lehmer, B. D.; Wik, D. R.; Hornschemeier, A. E.;

    2013-01-01

    We present results from three nearly simultaneous Nuclear Spectroscopic Telescope Array ( NuSTAR ) and Chandra monitoring observations between 2012 September 2 and 2012 November 16 of the local star-forming galaxy NGC 253. The 3-40 keV intensity of the inner ~ 20 arcsec ( ~ 400 pc) nuclear region......, as measured by NuSTAR , varied by a factor of ~ 2 across the three monitoring observations. The Chandra data reveal that the nuclear region contains three bright X-ray sources, including a luminous ( L2-10 keV ~ few × 1039 erg s-1 ) point source located ~ 1 arcsec from the dynamical center of the galaxy...... nature for this source. Future NuSTAR and Chandra monitoring would be well equipped to break the degeneracy between the AGN and ULX nature of the 2003 source, if again caught in a high state....

  19. New heavy-fermion antiferromagnet UPd2Cd20

    Science.gov (United States)

    Hirose, Yusuke; Doto, Hiroshi; Honda, Fuminori; Li, Dexin; Aoki, Dai; Haga, Yoshinori; Settai, Rikio

    2016-10-01

    We succeeded in growing a new high quality single crystal of a ternary uranium compound UPd2Cd20. From the electrical resistivity, magnetization, magnetic susceptibility, and specific heat experiments, UPd2Cd20 is found to be an antiferromagnetic heavy-fermion compound with the Néel temperature {{T}\\text{N}}   =  5 K and exhibits the large electronic specific heat coefficient γ exceeding 500 mJ (K2· mol)-1. This compound is the first one that exhibits the magnetic ordering with the magnetic moments of the U atom in a series of UT2X20 (T: transition metal, X  =  Al, Zn, Cd). UPd2Cd20 shows typical characteristic features in heavy-fermion systems such as a broad maximum in the magnetic susceptibility at {{T}{{χ\\text{max}}}} and a large coefficient A of T 2 term in the resistivity.

  20. Learning Based on Web2.0%基于Web2.0的学习

    Institute of Scientific and Technical Information of China (English)

    马金凤

    2011-01-01

    对基于Web 2.0的学习进行了论述.通过分析Web 2.0的模式和特征,探讨了Web 2.0在教学过程中对于教师和学习者产生的新的教学、学习方式,考察了Web 2.0对于学习资源进行的知识管理,提出了在Web 2.0学习中对学习者生存能力和道德规范的要求.

  1. Formulae for the secondary electron yield and total stopping power from 0.8 keV to 10 keV for metals

    Indian Academy of Sciences (India)

    XIE A G; XIAO S Y; WANG L

    2016-05-01

    Based on the range–energy relationship, the characteristics of secondary electron emission, some relationship between the secondary electron yield $\\delta$ and experimental results, the universal formulae for $\\delta_{0.8−2}$ (the subscript indicates that the energy range of primary energy atthe surface W$_{\\rm po}$ is from 0.8 keV to 2 keV) and $\\delta_{2−10}$ for metals were deduced. The $\\delta_{0.8−10}$ calculated with the universal formulae and the$\\delta_{0.8−10}$ measured experimentally were compared, and the scattering of $\\delta$ for the same metal was analysed. Finally, we concluded that the formulae were universal for $\\delta_{0.8−10}$ for metals. On the basis of some relationship between parameters of $\\delta$, wededuce a formula for expressing total stopping power $S_{0.8−10}$ as a function of $S_{10−30}, \\delta_{0.8−10}, \\delta_{10−30}$, backscattered coefficient $\\heta_{0.8−10}, \\heta_{10−30}$ and W$_{\\rm po}. The calculated $S_{0.8−10}$ were compared with the values measured experimentally and it was concluded that the formula to estimate $S_{0.8−10}$ was universal for metals.

  2. UTM TCL 2.0 Software Version Description (SVD) Document

    Science.gov (United States)

    Mcguirk, Patrick

    2017-01-01

    This is the Unmanned Aircraft Systems (UAS) Traffic Management (UTM) Technical Capability Level(TCL) 2.0 Software Version Description (SVD) document. This UTM TCL 2.0 SVD describes the following four topics: 1. Software Release Contents: A listing of the files comprising this release 2. Installation Instructions: How to install the release and get it running 3. Changes Since Previous Release: General updates since the previous UTM release 4. Known Issues: Known issues and limitations in this release

  3. Comment on the paper "Dark matter searches going bananas: the contribution of Potassium (and Chlorine) to the 3.5 keV line" by T. Jeltema and S. Profumo

    CERN Document Server

    Boyarsky, A; Iakubovskyi, D; Ruchayskiy, O

    2014-01-01

    We revisit the X-ray spectrum of the central 14' of the Andromeda galaxy, discussed in our previous work [1402.4119]. Recently in [1408.1699] it was claimed that if one limits the analysis of the data to the interval 3-4 keV, the significance of the detection of the line at 3.53 keV drops below 2 sigma. In this note we show that such a restriction is not justified, as the continuum is well-modeled as a power law up to 8 keV, and parameters of the background model are well constrained over this larger interval of energies. This allows for a detection of the line at 3.53 keV with a statistical significance greater than ~3 sigma and for the identification of several known atomic lines in the energy range 3-4 keV. Limiting the analysis to the 3-4 keV interval results in increased uncertainty, thus decreasing the significance of the detection. We also argue that, with the M31 data included, a consistent interpretation of the 3.53 keV line as an atomic line of K XVIII in all studied objects is problematic.

  4. School and Web 2.0: a critical perspective

    OpenAIRE

    Selwyn, Neil; Gouseti, Anastasia

    2009-01-01

    Este artículo ofrece una visión general de las implicaciones educativas de las tecnologías web 2.0 en las escuelas, sosteniendo que las representaciones actuales del uso de web 2.0 duplican una vieja tendencia en la educación de reacciones exageradas e ideológicamente lanzadas hacia la tecnología. El artículo concluye argumentando a favor de la necesidad de retener una perspectiva prudente, que no crítica, de las escuelas y web 2.0,buscando encontrar maneras de usar las tecnologías w...

  5. Enabling Problem Based Learning through Web 2.0 Technologies

    DEFF Research Database (Denmark)

    Tambouris, Efthimios; Panopoulou, Eleni; Tarabanis, Konstantinos

    2012-01-01

    Advances in Information and Communications Technology (ICT), particularly the so-called Web 2.0, are affecting all aspects of our life: how we communicate, how we shop, how we socialise, and how we learn. Facilitating learning through the use of ICT, also known as eLearning, is a vital part...... of modern educational systems. Established pedagogical strategies, such as Problem Based Learning (PBL), are being adapted for online use in conjunction with modern Web 2.0 technologies and tools. However, even though Web 2.0 and progressive social-networking technologies are automatically associated...

  6. E-Learning 2.0: Learning Redefined

    OpenAIRE

    Kumar, Rupesh

    2009-01-01

    The conventional e-learning approach emphasizes a learning system more than a learning environment. While traditional e-learning systems continue to be significant, there is a new set of services emerging, embracing the philosophy of Web 2.0. Known as e-learning 2.0, it aims to create a personalized learning environment. E-learning 2.0 combines the use of discrete but complementary tools and web services to support the creation of ad-hoc learning communities. This paper discusses the influenc...

  7. Online Reputation Systems in Web 2.0 Era

    Science.gov (United States)

    Zheng, Weijun; Jin, Leigh

    Web 2.0 has transformed how reputation systems are designed and used by the Web. Based on a thorough review of the existing online reputation systems and their challenges in use, this paper studied a case of Amazon’s reputation system for the impacts of Web 2.0. Through our case study, several distinguished features of new generation reputation systems are noted including multimedia feedbacks, reviewer centered, folksonomy, community contribution, comprehensive reputation, dynamic and interactive system etc. These new developments move towards a relatively trustworthy and reliable online reputation system in the Web 2.0 era.

  8. Theater Missile Defense Extended Test Range Supplemental Environmental Impact Statement - Eglin Gulf Test Range. Volume 2

    Science.gov (United States)

    1998-07-01

    Gulf of Mexico .............................3-297 3.2.3-3 Locations of Cetaceans (Whales and Dolphins) .....................................3-299... Cetaceans on the Upper Continental Slope in the North-Central Gulf of Mexico,” Fishery Bulletin, No. 92: 773-786. Myers, R. and J. Ewel, 1992. Ecosystems...on Levels of Environmental Noise Requisite to Protect Public Health and Welfare with an Adequate Margin of Safety, March. U.S. Environmental

  9. Search for a 17 keV neutrino in the internal bremsstrahlung spectrum of 125I

    Science.gov (United States)

    Hindi, M. M.; Kozub, R. L.; Robinson, S. J.

    1994-06-01

    We have searched for evidence of the emission of a 17 keV neutrino in the internal bremsstrahlung (IB) spectrum accompanying the electron capture decay of 125I. The IB spectrum, recorded in a planar Ge detector, has 1.2×106 counts per keV at 17 keV below the 2p end point. We set an upper limit of 0.4% for the admixture of a 17 keV neutrino, at the 90% confidence level, and exclude a 0.8% admixture at the 99.6% confidence level. The QEC value is found to be 185.77+/-0.06 keV. We also find that the recent calculations of Surić et al., which employ relativistic self-consistent-field atomic wave functions, reproduce the shape and relative intensity of IB partial spectra within a few percent.

  10. $\\mathbf{\\alpha}$-induced reaction cross sections in the mass range $\\mathbf{A \\approx 20 - 50}$: a critical review

    CERN Document Server

    Mohr, Peter

    2016-01-01

    In a recent review it was shown that the cross sections of $\\alpha$-induced reactions in the $A \\approx 20 - 50$ mass range follow a general and smooth trend in most cases. For comparison of cross sections of different targets at various energies the method of reduced cross sections $\\sigma_{\\rm{red}}$ and reduced energies $E_{\\rm{red}}$ was used. Four outliers were identified: $^{36}$Ar and $^{40}$Ar with unusally small cross sections and $^{23}$Na and $^{33}$S with unusually large cross sections. New data for $^{23}$Na were presented at this NPA-7 conference; contrary to the previous data, these new data fit into the general systematics. In addition, a relation between the most effective energy $E_0$ for astrophysical reaction rates (the so-called Gamow window) and the reduced energy $E_{\\rm{red}}$ is presented.

  11. Coherent Pair Production by Photons in the 20-170 GeV Energy Range Incident on Crystals and Birefringence

    CERN Document Server

    Apyan, A; Badelek, B; Ballestrero, S; Biino, C; Birol, I; Cenci, P; Connell, S H; Eichblatt, S; Fonseca, T; Freund, A; Gorini, B; Groess, R; Ispirian, K; Ketel, T; Kononets, Yu V; López, A; Mangiarotti, A; Sellschop, J P Friedel; Shieh, M; Sona, P; Strakhovenko, V M; Uggerhøj, Erik; Uggerhøj, U; Van Rens, B; Velasco, M; Vilakazi, Z Z; Wessely, O; Ünel, G; Kononets, Yu.V.

    2003-01-01

    The cross section for coherent pair production by linearly polarised photons in the 20-170 GeV energy range was measured for photon aligned incidence on ultra-high quality diamond and germanium crystals. The theoretical description of coherent bremsstrahlung and coherent pair production phenomena is an area of active theoretical debate and development. However, under our experimental conditions, the theory predicted the combined cross section and polarisation experimental observables very well indeed. In macroscopic terms, our experiment measured a birefringence effect in pair production in a crystal. This study of this effect also constituted a measurement of the energy dependent linear polarisation of photons produced by coherent bremsstrahlung in aligned crystals. New technologies for manipulating high energy photon beams can be realised based on an improved understanding of QED phenomena at these energies. In particular, this experiment demonstrates an efficient new polarimetry technique. The pair product...

  12. [Medicine 2.0: the stakes of participatory medicine].

    Science.gov (United States)

    Silber, Denise

    2009-10-01

    Web 2.0: interactive, collaborative tools (wikis, social networks, blogs, virtual worlds) make Internet users active participants rather than simple consumers. Medicine 2.0: mentalities, approaches, and medical practices are changing, thanks to greater access to information, communal exchanges, and the comparison of personal experiences. Beyond the many wikis, blogs, and other collaborative tools, the site PatientsLikeMe.com stands out from the 2.0 crowd by its graphic representation of the clinical results entered by patients. Various European Web 2.0 sites exist as well. The risks reside in the reliability of information and the privacy of patient data. The challenges are to use these new resources to improve the quality of care and participate in the profound change they are bringing to the healthcare system.

  13. VPLIV TEHNOLOGIJE WEB 2.0 NA POSLOVANJE PODJETJA

    OpenAIRE

    Šuhel, Peter

    2009-01-01

    Diplomska naloga opisuje uporabo Web 2.0 tehnologij v podjetjih. Tehnologija Web 2.0 je na spletu že zelo razširjena, praktično so vse najbolj popularne storitve na internetu sestavljene iz Web 2.0 tehnologije. Vendar ta tehnologija še ni močno razširjena v podjetjih, kjer se je izkazala za zelo uporaben in učinkovit način prenosa, beleženja in pisanja informacij. Zaradi uspešnosti te tehnologije v podjetjih, ki so vpeljala E2.0, je smotrno raziskati ta nov način uporabe programske opreme v p...

  14. Enterprise 2.0 and the Future of Business

    Institute of Scientific and Technical Information of China (English)

    MICHAEL O'NEILL

    2006-01-01

    @@ If you are still struggling to get a clear understanding of exactly what Web 2.0 means and how the current hype surrounding social networking and information sharing websites are relevant to your company's needs, fear not.

  15. Exact deconstruction of the 6D (2,0) theory

    Science.gov (United States)

    Hayling, J.; Papageorgakis, C.; Pomoni, E.; Rodríguez-Gómez, D.

    2017-06-01

    The dimensional-deconstruction prescription of Arkani-Hamed, Cohen, Kaplan, Karch and Motl provides a mechanism for recovering the A-type (2,0) theories on T 2, starting from a four-dimensional N=2 circular-quiver theory. We put this conjecture to the test using two exact-counting arguments: in the decompactification limit, we compare the Higgs-branch Hilbert series of the 4D N=2 quiver to the "half-BPS" limit of the (2,0) superconformal index. We also compare the full partition function for the 4D quiver on S 4 to the (2,0) partition function on S 4 × T 2. In both cases we find exact agreement. The partition function calculation sets up a dictionary between exact results in 4D and 6D.

  16. RadCat 2.0 User Guide.

    Energy Technology Data Exchange (ETDEWEB)

    Osborn, Douglas.; Weiner, Ruth F.; Mills, George Scott; Hamp, Steve C.; O' Donnell, Brandon, M.; Orcutt, David J.; Heames, Terence J.; Hinojosa, Daniel

    2005-01-01

    This document provides a detailed discussion and a guide for the use of the RadCat 2.0 Graphical User Interface input file generator for the RADTRAN 5.5 code. The differences between RadCat 2.0 and RadCat 1.0 can be attributed to the differences between RADTRAN 5 and RADTRAN 5.5 as well as clarification for some of the input parameters. 3

  17. Happiness and the Family 2.0 Paradigm

    Science.gov (United States)

    Mocan, Rodica; Racorean, Stefana

    Does new media technology have the potential to make us happier? This paper explores the influence of new information communication technologies on family life satisfaction while analyzing some of the factors that determine changes in the way we live our lives in the information age. Family 2.0 is the new paradigm of family life and the emergence of Web 2.0 type of applications is at the very core of its existence.

  18. Zend framework 2.0 by example beginner's guide

    CERN Document Server

    Shasankar, Krishna

    2013-01-01

    Zend Framework 2.0 by Example: Beginner's Guide is a step-by-step guide that aims to empower you to build web applications packed with some really exciting features using Zend Framework 2.0.If you are a PHP Developer who is new to Zend Framework, but you want to get hands-on with the product quickly, this book is for you. Basic knowledge of object oriented programming with PHP is expected.

  19. What Web 2.0 Means to Facilities Professionals

    Science.gov (United States)

    Allen, Scott

    2008-01-01

    It's official--the Web is now social. Actually, it has always been social to a degree, but now it's "mostly" social. A lot of terms have been coined or adopted to describe various aspects of this phenomenon--social media, social networking, consumer-generated media (CGM) and Web 2.0. While it is hard to define "exactly" what Web 2.0 is, or when…

  20. Measurements of complex permittivity of microwave substrates in the 20 to 300 K temperature range from 26.5 to 40.0 GHz

    Science.gov (United States)

    Miranda, Felix A.; Gordon, William L.; Heinen, Vernon O.; Ebihara, Ben T.; Bhasin, Kul B.

    1990-01-01

    A knowledge of the dielectric properties of microwve substrates at low temperatures is useful in the design of superconducting microwave circuits. Results are reported for a study of the complex permittivity of sapphire (Al2O3), magnesium oxide (MgO), silicon oxide (SiO2), lanthanum aluminate (LaAlO3), and zirconium oxide (ZrO2), in the 20 to 300 Kelvin temperature range, at frequencies from 26.5 to 40.0 GHz. The values of the real and imaginary parts of the complex permittivity were obtained from the scattering parameters, which were measured using an HP-8510 automatic network analyzer. For these measurements, the samples were mounted on the cold head of a helium gas closed cycle refrigerator, in a specially designated vacuum chamber. An arrangement of wave guides, with mica windows, was used to connect the cooling system to the network analyzer. A decrease in the value of the real part of the complex permittivity of these substrates, with decreasing temperature, was observed. For MgO and Al2O3, the decrease from room temperature to 20 K was of 7 and 15 percent, respectively. For LaAlO3, it decreased by 14 percent, for ZrO2 by 15 percent, and for SiO2 by 2 percent, in the above mentioned temperature range.

  1. Emergent Learning and Learning Ecologies in Web 2.0

    Directory of Open Access Journals (Sweden)

    Roy Williams

    2011-03-01

    Full Text Available This paper describes emergent learning and situates it within learning networks and systems and the broader learning ecology of Web 2.0. It describes the nature of emergence and emergent learning and the conditions that enable emergent, self-organised learning to occur and to flourish. Specifically, it explores whether emergent learning can be validated and self-correcting and whether it is possible to link or integrate emergent and prescribed learning. It draws on complexity theory, communities of practice, and the notion of connectivism to develop some of the foundations for an analytic framework, for enabling and managing emergent learning and networks in which agents and systems co-evolve. It then examines specific cases of learning to test and further develop the analytic framework.The paper argues that although social networking media increase the potential range and scope for emergent learning exponentially, considerable effort is required to ensure an effective balance between openness and constraint. It is possible to manage the relationship between prescriptive and emergent learning, both of which need to be part of an integrated learning ecology.

  2. SPHY v2.0: Spatial Processes in HYdrology

    Directory of Open Access Journals (Sweden)

    W. Terink

    2015-02-01

    Full Text Available This paper introduces and presents the Spatial Processes in HYdrology (SPHY model (v2.0, its development background, its underlying concepts, and some typical applications. The SPHY model is developed using the best components of existing and well-tested simulation models, and is developed with the explicit aim to simulate terrestrial hydrology at flexible scales, under various land use and climate conditions. SPHY is a spatially distributed leaky bucket type of model, and is applied on a cell-by-cell basis. The model is written in the Python programming language using the PCRaster dynamic modelling framework. Compared to other hydrological models, that typically focus on the simulation of streamflow only, the SPHY model has several advantages: it (i integrates most relevant hydrological processes, (ii is setup modular, (iii is easy adjustable and applicable, (iii can easily be linked to remote sensing data, and (iv can be applied for operational as well as strategic decision support. The most relevant hydrological processes that are integrated in the SPHY model are rainfall–runoff processes, cryosphere processes, evapotranspiration processes, the simulation of dynamic vegetational cover, lake/reservoir outflow, and the simulation of rootzone moisture contents. Studies in which the SPHY model was successfully applied and tested are described in this paper, and range from (i real-time soil moisture predictions to support irrigation management in lowland areas, to (ii detailed climate change impact studies in snow and glacier-fed river basins, to (iii operational flow forecasting in mountainous catchments.

  3. SPHY v2.0: Spatial Processes in HYdrology

    Science.gov (United States)

    Terink, W.; Lutz, A. F.; Simons, G. W. H.; Immerzeel, W. W.; Droogers, P.

    2015-07-01

    This paper introduces and presents the Spatial Processes in HYdrology (SPHY) model (v2.0), its development background, its underlying concepts, and some example applications. SPHY has been developed with the explicit aim of simulating terrestrial hydrology on flexible scales, under various physiographical and hydroclimatic conditions, by integrating key components from existing and well-tested models. SPHY is a spatially distributed leaky bucket type of model, and is applied on a cell-by-cell basis. The model is written in the Python programming language using the PCRaster dynamic modeling framework. SPHY (i) integrates most hydrologic processes, (ii) has the flexibility to be applied in a wide range of hydrologic applications, and (iii) on various scales, and (iv) can easily be implemented. The most relevant hydrological processes that are integrated into the SPHY model are rainfall-runoff processes, cryosphere processes, evapotranspiration processes, the dynamic evolution of vegetation cover, lake/reservoir outflow, and the simulation of root-zone moisture contents. Studies in which the SPHY model was successfully applied and tested are described in this paper, including (i) real-time soil moisture predictions to support irrigation management in lowland areas, (ii) climate change impact studies in snow- and glacier-fed river basins, and (iii) operational flow forecasting in mountainous catchments.

  4. Web 2.0 ve Library 2.0: Dijital yerliler için bilgi hizmetleri

    OpenAIRE

    Tonta, Yaşar

    2009-01-01

    Facebook, MySpace, Flickr are YouTube among the most frequented web sites with Web 2.0 features. Features such as social networking and collaboration, personalization, user-generated content and metadata will enrich the user experience and make web sites more attractive for users. If library and information centers are to provide more effective information services, they have to add Web 2.0 and Library 2.0 to their services. Otherwise, today's digital natives who grew up with the Internet,...

  5. Effective atomic numbers and electron densities of bacteriorhodopsin and its comprising amino acids in the energy range 1 keV–100 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Ahmadi, Morteza; Lunscher, Nolan [Waterloo Institute for Nanotechnology and Department of Systems Design Engineering, University of Waterloo, 200 University Ave., W., Waterloo, Ontario, Canada N2L 3G1 (Canada); Yeow, John T.W., E-mail: jyeow@uwaterloo.ca [Waterloo Institute for Nanotechnology and Department of Systems Design Engineering, University of Waterloo, 200 University Ave., W., Waterloo, Ontario, Canada N2L 3G1 (Canada)

    2013-04-01

    Recently, there has been an interest in fabrication of X-ray sensors based on bacteriorhodopsin, a proton pump protein in cell membrane of Halobacterium salinarium. Therefore, a better understanding of interaction of X-ray photons with bacteriorhodopsin is required. We use WinXCom program to calculate the mass attenuation coefficient of bacteriorhodopsin and its comprising amino acids for photon energies from 1 keV to 100 GeV. These amino acids include alanine, arginine, asparagine, aspartic acid, glutamine, glutamic acid, glycine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, valine, Asx1, Asx2, Glx1 and Glx2. We then use that data to calculate effective atomic number and electron densities for the same range of energy. We also emphasize on two ranges of energies (10–200 keV and 1–20 MeV) in which X-ray imaging and radiotherapy machines work.

  6. 20 CFR 210.2 - Definition of service.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Definition of service. 210.2 Section 210.2... RAILROAD SERVICE § 210.2 Definition of service. Service means a period of time for which an employee... an employee for creditable military service as defined in part 212 of this chapter. Service...

  7. 20 CFR 322.2 - General definition of remuneration.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false General definition of remuneration. 322.2... INSURANCE ACT REMUNERATION § 322.2 General definition of remuneration. (a) Remuneration. (1) Remuneration... accruing. (2) Remuneration includes income in the form of a commodity, service, or privilege if, before...

  8. 20 CFR 330.2 - Computation of daily benefit rate.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Computation of daily benefit rate. 330.2 Section 330.2 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT DETERMINATION OF DAILY BENEFIT RATES § 330.2 Computation of daily benefit rate. (a)...

  9. Technical Analysis of IEC 61850 Ed 2.0%IEC 61850 Ed 2.0技术分析

    Institute of Scientific and Technical Information of China (English)

    任雁铭; 操丰梅; 张军

    2013-01-01

    对IEC 61850 Ed 2.0的文件构成和技术路线进行了介绍.对比IEC 61850 Ed 1.0,从数据模型、工程配置语言和一致性测试3个方面,对IEC 61850 Ed 2.0的技术特点进行了技术分析.从设备制造商和检测中心2个方面,讨论了如何从IEC 61850 Ed 1.0迁徙到IEC 61850 Ed 2.0.%The profile and technical philosophy of IEC 61850 Ed 2.0 are described. By comparison with IEC 61850 Ed 1.0, an analysis is made of the technical features of IEC 61850 Ed 2.0 data model, substation configuration language and conformance test. A discussion is made of shifting from IEC 61850 Ed 1.0 to IEC 61850 Ed 2.0 with respect to the manufacturer and testing organization.

  10. The 2.0 Attitude: Politics beyond Blogs

    Directory of Open Access Journals (Sweden)

    Roc Fages Ramió

    2008-09-01

    Full Text Available

    La Actitud 2.0 es el elemento clave para aprovechar las posibilidades que el trabajo y la relación en red proporciona a empresas, organizaciones y administraciones. Si una persona es 2.0 quiere decir que utiliza las herramientas de la Web 2.0 para generar red y obtener beneficios personales o profesionales, individuales y colectivos, a partir de compartir conocimiento.

    Este artículo empieza definiendo la Web 2.0 para demostrar que sin una actitud hacia este fenómeno el concepto no puede llegar a ningún sitio. A partir de esta conceptualización, el documento desarrolla la aplicación de la Actitud 2.0 a nivel de la política. Aquello que se conoce como Política 2.0, dice el texto, está aplicándose más desde el punto de vista de la ciudadanía que de los mismos políticos. Por lo tanto, la Política 2.0 crea una nueva forma de hacer política por parte de los ciudadanos. Eso quiere decir que éstos intentan generar una red de la que los políticos muchas veces no forman parte, incluso aunque se hayan integrado en el ámbito 2.0. El problema, pues, es que muchos políticos supuestamente 2.0 sólo utilizan las herramientas -blogs, Facebook, YouTube, Twitter...- sin entrar a fondo en las capacidades de la red. Porque, de hecho, la Política 2.0 les permitiría poder conocer, compartir y escuchar más directamente las necesidades y los intereses de la misma ciudadanía.

    Llegados a este punto, y después de repasar algunas iniciativas interesantes de Política 2.0, el artículo acaba destacando la importancia de la nueva generación de nativos digitales, de personas que han nacido con el fenómeno 2.0 integrado, la generación de la Nintendo. Este grupo de jóvenes son los que tienen que marcar las tendencias que en un futuro muy inmediato serán realidades: trabajo y relación en red elevados al máximo exponente. Por lo tanto, les tiene que quedar claro a los políticos que, hoy por hoy, la Política 2.0 se

  11. Extrapolation Ionization Chamber Dosimetry of Fluorescent X-Ray Energies from 4.5 to 19.6 keV.

    Science.gov (United States)

    Rakowski, Joseph T; Tucker, Mark A; Snyder, Michael G; Makar, Simon P; Yudele, Mark; Burmeister, Jay; Joiner, Michael C

    2016-09-01

    Characteristic X rays of energies less than approximately 20 keV are of interest in radiobiology and radiation oncology. There is evidence that these low-energy photons produce higher relative biological effectiveness (RBE) and lower oxygen enhancement ratio (OER) relative to higher energies. Lower energy X rays also offer the advantage of healthy tissue sparing beyond the target treatment depth. Electronic brachytherapy systems that can deliver characteristic and bremsstrahlung X rays of varying energy are in clinical use as well as under development. We performed low-energy extrapolation ionization chamber dosimetry using two methods: 1. the exposure-to-dose method; and 2. the Burlin theory method combined with the extrapolation chamber method of Klevenhagen. We investigated fluorescent X rays emitted from seven metals: titanium (Ti, Z = 22); chromium (Cr, Z = 24); iron (Fe, Z = 26); cobalt (Co, Z = 27); copper (Cu, Z = 29); zinc (Zn, Z = 30); and molybdenum (Mo, Z = 42). X rays were produced by irradiation of the metals with a 55 kVp, 45 mA silver anode spectrum. The data obtained were air kerma rate (cGy/min), and radiation dose rate (cGy/min) in phosphate-buffered saline (PBS) solution and water. Air kerma rates ranged from 3.55 ± 0.10 to 14.36 ± 0.39 cGy/min. Dose rates ranged from 3.85 ± 0.10 to 16.96 ± 0.46 cGy/min in PBS and 3.59 ± 0.10 to 16.06 ± 0.43 cGy/min in water. Dose-rate energy dependence of both models was examined by taking a ratio of measured to Monte Carlo calculated dose rates. Dosimetry method 1 exhibited a linear relationship across all energies with a slope of 0.0127 keV(-1) and R(2) of 0.9276. Method 2 exhibited a linear relationship across all energies with a slope of 0.0467 keV(-1) and R(2) of 0.9933. Method 1 or 2 may be used as a relative dosimetry system to derive dose rates to water by using a second reference ion chamber with a NIST-traceable calibration for the molybdenum spectrum.

  12. Onlinestudie: Wissenschaftliches Arbeiten im Web 2.0

    Directory of Open Access Journals (Sweden)

    Moskaliuk, Johannes

    2009-07-01

    Full Text Available Das Web 2.0 eröffnet Wissenschaftlerinnen und Wissenschaftlern neue Möglichkeiten mit Wissen und Informationen umzugehen: Das Recherchieren von Informationen und Quellen, der Austausch von Wissen mit anderen, das Verwalten von Ressourcen und das Erstellen von eigenen Inhalten im Web ist einfach und kostengünstig möglich. Dieser Artikel thematisiert die Bedeutung des Web 2.0 für den Umgang mit Wissen und Informationen und zeigt auf, wie durch die Kooperation vieler Einzelner das Schaffen von neuem Wissen und von Innovationen möglich wird. Diskutiert werden der Einfluss des Web 2.0 auf die Wissenschaft und mögliche Vor- und Nachteile der Nutzung. Außerdem wird ein kurzer Überblick über Studien gegeben, die die Nutzung des Web 2.0 in der Gesamtbevölkerung untersuchen.Im empirischen Teil des Artikels werden Methode und Ergebnisse der Befragungsstudie „Wissenschaftliches Arbeiten im Web 2.0“ vorgestellt. Befragt wurden Nachwuchswissenschaftlerinnen und Nachwuchswissenschaftler in Deutschland zur Nutzung des Web 2.0 für die eigene wissenschaftliche Arbeit. Dabei zeigt sich, dass insbesondere die Wikipedia von einem Großteil der Befragten intensiv bis sehr intensiv für den Einstieg in die Recherche verwendet wird. Die aktive Nutzung des Web 2.0, z.B. durch das Schreiben eines eigenen Blogs oder dem Mitarbeiten bei der Online-Enzyklopädie Wikipedia ist bis jetzt noch gering. Viele Dienste sind unbekannt oder werden eher skeptisch beurteilt, der lokale Desktopcomputer wurde noch nicht vom Web als zentraler Speicherort abgelöst.

  13. Validation and verification of the OPI 2.0 System

    Directory of Open Access Journals (Sweden)

    Abelson R

    2012-04-01

    Full Text Available Richard Abelson1,2, Keith J Lane3, John Rodriguez3, Patrick Johnston3, Endri Angjeli3, George Ousler3, Douglas Montgomery11School of Computing, Informatics, and Decision Systems Engineering, Arizona State University, Tempe, AZ, 2Statistics and Data Corporation, Tempe, AZ, 3Ora, Inc, Andover, MA, USAPurpose: The Ocular Protection Index (OPI 2.0 System was developed to evaluate ocular surface protection under a natural blink pattern and normal visual conditions. The OPI 2.0 System implements fully automated software algorithms which provide a real-time measurement of corneal exposure (breakup area for each interblink interval during a 1-minute video. Utilizing this method, the mean breakup area (MBA and OPI 2.0 (MBA/interblink interval were calculated and analyzed. The purpose of this study was to verify and validate the OPI 2.0 System for its ability to distinguish between dry eye and normal subjects, and to accurately identify breakup area.Methods: In order to verify and validate the OPI 2.0 System, a series of artificial images and a series of still image frames captured during an actual clinical session using fluorescein staining videography were analyzed. Finally, a clinical validation process was completed to determine the effectiveness and clinical relevance of the OPI 2.0 System to differentiate between dry eye and normal subjects.Results: Software analysis verification conducted in a set of artificially constructed images and in actual videos both saw minimal error rates. MBA and OPI 2.0 calculations were able to distinguish between the qualifying eyes of dry eye and normal subjects in a statistically significant fashion (P < 0.001 for both outcomes. As expected, dry eye subjects had a higher MBA and OPI 2.0 than normal subjects (0.232, dry eye; 0.040, normal and 0.039, dry eye; 0.006, normal, respectively. Results for the worst eyes and all qualifying analyses based on staining, forced-stare tear film breakup time, and MBA were

  14. Indico — the Road to 2.0

    Science.gov (United States)

    Ferreira, P.; Avilés, A.; Dafflon, J.; Mönnich, A.; Trichopoulos, I.

    2015-12-01

    Indico has come a long way since it was first used to organize CHEP 2004. More than ten years of development have brought new features and projects, widening the application's feature set and enabling event organizers to work even more efficiently. While that has boosted the tool's usage and facilitated its adoption by a remarkable 300,000 events (at CERN only), it has also generated a whole new range of challenges, which have been the target of the team's attention for the last 2 years. One of them was that of scalability and the maintainability of the current database solution (ZODB). After careful consideration, the decision was taken to move away from ZODB to PostgreSQL, a relational and widely-adopted solution that will permit the development of a more ambitious feature set as well as improved performance and scalability. A change of this type is by no means trivial in nature and requires the refactoring of most backend code as well as the full rewrite of significant portions of it. We are taking this opportunity to modernize Indico, by employing standard web modules, technologies and concepts that not only make development and maintenance easier but also constitute an upgrade to Indico's stack. The first results are already visible since August 2014, with the full migration of the Room Booking module to the new paradigm. In this paper we explain what has been done so far in the context of this ambitious migration, what have been the main findings and challenges, as well as the main technologies and concepts that will constitute the foundation of the resultant Indico 2.0.

  15. Library 2.0, information and digital literacies in the light of the contradictory nature of Web 2.0

    Directory of Open Access Journals (Sweden)

    Tibor Koltay

    2010-12-01

    Full Text Available Desk research was done to examine the importance of raising awareness of differences between professional content and content produced by the amateurs of the Web 2.0. The commercial nature of Web 2.0 was briefly explained. Questions related to amateurism have been raised and amateur contents characterizing Web 2.0 were contrasted to professional ones. The results show that some principles can be laid down. First of all, the need in literacies of students, teaching staff and researchers is different from that of other categories of users, when the former are fulfilling their professional roles. These needs can be satisfied mainly by services that traditionally have been provided by academic and special libraries, while making use of Web 2.0 tools could mean moving towards the goals of public library users. Second, information literacy and digital literacy alongside with adequately defined Library 2.0 are expedient in the era of Web 2.0 to support user needs by the provision of appropriate library resources and services.

  16. Development of a 110-m-mA, 75-keV proton injector for high-current, CW linacs

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, J.D.; Bolme, G.O.; Hansborough, L.D. [and others

    1996-09-01

    A dc proton injector is being developed for a 6.7 MeV CW RFQ at Los Alamos. The RFQ input beam requirements are 75 keV energy, 110 mA dc proton current, and 0.20 {pi}mm-mrad rms normalized emittance. The injector has now produced a 75-keV, 117-mA dc proton beam (130 mA total current) with the required emittance. The emittance has been measured after a 2.1 m long two-solenoid beam transport system. The measured emittance can be explained in terms of the ion source emittance and beam transport through the focusing elements. Measured proton fractions are 90-92% of the beam current. Engineering of the accelerating column high-voltage design is being improved to increase the injector reliability. Injector design details and status are presented.

  17. SALL4 and NFATC2: two major actors of interstitial 20q13.2 duplication.

    Science.gov (United States)

    Briand-Suleau, A; Martinovic, J; Tosca, L; Tou, B; Brisset, S; Bouligand, J; Delattre, V; Giurgea, I; Bachir, J; Folliot, P; Goumy, C; Francannet, C; Guiochon-Mantel, A; Benachi, A; Vermeesch, J; Tachdjian, G; Vago, P; Goossens, M; Métay, C

    2014-03-01

    Interstitial duplication within the long arm of chromosome 20 is an uncommon chromosome structural abnormality. We report here the clinical and molecular characterization associated with pure 20q13.2 duplication in three unrelated patients. The most frequent clinical features were developmental delay, facial dysmorphism, cardiac malformation and skeletal anomalies. All DNA gains occurred de novo, ranging from 1.1 Mb to 11.5 Mb. Compared with previously reported conventional cytogenetic analyses, oligonucleotides array CGH allowed us to refine breakpoints and determine the genes of interest in the region. Involvement of SALL4 in cardiac malformations and NFATC2 gene disruption in both cardiac and skeletal anomalies are discussed.

  18. Evolution of nanodot morphology on polycarbonate (PC) surfaces by 40 keV Ar{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, Meetika, E-mail: meetika89@gmail.com; Chawla, Mahak; Gupta, Divya; Shekhawat, Nidhi; Sharma, Annu; Aggarwal, Sanjeev [Department of Physics, Kurukshetra University, Kurukshetra - 136119 (India)

    2016-05-06

    In the present paper we have discussed the effect of 40 keV Ar{sup +} ions irradiation on nanoscale surface morphology of Polycarbonate (PC) substrate. Specimens were sputtered at off normal incidences of 30°, 40° and 50° with the fluence of 1 × 10{sup 16} Ar{sup +}cm{sup −2}. The topographical behaviour of specimens was studied by using Atomic Force Microscopy (AFM) technique. AFM study demonstrates the evolution of nano dot morphology on PC specimens on irradiating with 1 × 10{sup 16} Ar{sup +}cm{sup −2}. Average size of dots varied from 37-95 nm in this specified range of incidence while density of dots varied from 0.17-3.0 × 107 dotscm{sup −2}. Such variations in morphological features have been supported by estimation of ion range and sputtering yield through SRIM simulations.

  19. ReefBase 2.0: a contribution to environmental conservation on a global scale

    OpenAIRE

    Halmarick, L.

    1997-01-01

    The 1997 International Year of the Reef sees the release of ReefBase 2.0: a global database on coral reefs and their resources. It provides the most comprehensive and accessible repository of information to date. Containing information on over 7000 coral reefs in more than 123 countries, ReefBase 2.0 offers an extensive range of time-related data pertaining to coastal tourism, benthic environment ecology, fish population statistics, oceanography, socioeconomics, mariculture, and harvest activ...

  20. Evaluating the use and impact of Web 2.0 technologies in local government

    OpenAIRE

    Sivarajah, U; Irani, Z.; Weerakkody, V

    2015-01-01

    Second generation web-based technologies (Web 2.0) such as social media and networking sites are increasingly being used by governments for activities ranging from open policy making to communication campaigns and customer service. However, this in turn has brought about additional challenges. By its very nature, Web 2.0 technologies are more interactive than the traditional models of information provision or creation of digital services. Such technologies open up a new set of benefits, costs...

  1. The Web 2.0 as Marketing Tool: Opportunities for SMEs

    OpenAIRE

    Constantinides, Efthymios

    2008-01-01

    The new generation of Internet applications widely known as Social Media or Web 2.0 offers corporations a whole range of opportunities for improving their marketing efficiency and internal operations. Web 2.0 applications have already become part of the daily life of an increasing number of consumers who regard them as prime channels of communication, information exchange, sharing of expertise, dissemination of individual creativity and entertainment. Web logs, podcasts, online forums and soc...

  2. The 14C(n,γ) cross section between 10 keV and 1 M

    CERN Document Server

    Reifarth, R; Forssén, C; Besserer, U; Couture, A; Dababneh, S; Dörr, L; Görres, J; Haight, R C; Käppeler, F; Mengoni, A; O'Brien, S; Patronis, N; Plag, R; Rundberg, R S; Wiescher, M; Wilhelmy, J B

    2008-01-01

    The neutron capture cross section of 14C is of relevance for several nucleosynthesis scenarios such as inhomogeneous Big Bang models, neutron induced CNO cycles, and neutrino driven wind models for the r process. The 14C(n,γ) reaction is also important for the validation of the Coulomb dissociation method, where the (n,γ) cross section can be indirectly obtained via the time-reversed process. So far, the example of 14C is the only case with neutrons where both, direct measurement and indirect Coulomb dissociation, have been applied. Unfortunately, the interpretation is obscured by discrepancies between several experiments and theory. Therefore, we report on new direct measurements of the 14C(n,γ) reaction with neutron energies ranging from 20 to 800 keV.

  3. [Surgeon 2.0: the challenge is on the Web].

    Science.gov (United States)

    Belda Lozano, Ricardo; Ferrer Márquez, Manuel; García Torrecillas, Juan Manuel; Alvarez García, Antonio; Reina Duarte, Angel

    2013-01-01

    Numerous articles and opinions have been published in the last few years on how the Internet is changing clinical practice. In this article we focus on describing 2 aspects that we believe are fundamental in the web 2.0 and Medicine-Surgery inter-relationship: a) web 2.0 conceptualisation and its differences with other pre-existing tools, and b) a description of some of the tools that from a medical-surgical view could be of major interest to the professionals, the patients, and interaction between both. The time has arrived to board train 2.0, where the channels of communication between the professionals, and between them and the patients, are improving disease situations daily, to improve learning through contact with other physicians and surgeons, at the same time providing an excellent resource for maintaining health and to know the disease and its treatment.

  4. Pilots 2.0: DIRAC pilots for all the skies

    Science.gov (United States)

    Stagni, F.; Tsaregorodtsev, A.; McNab, A.; Luzzi, C.

    2015-12-01

    In the last few years, new types of computing infrastructures, such as IAAS (Infrastructure as a Service) and IAAC (Infrastructure as a Client), gained popularity. New resources may come as part of pledged resources, while others are opportunistic. Most of these new infrastructures are based on virtualization techniques. Meanwhile, some concepts, such as distributed queues, lost appeal, while still supporting a vast amount of resources. Virtual Organizations are therefore facing heterogeneity of the available resources and the use of an Interware software like DIRAC to hide the diversity of underlying resources has become essential. The DIRAC WMS is based on the concept of pilot jobs that was introduced back in 2004. A pilot is what creates the possibility to run jobs on a worker node. Within DIRAC, we developed a new generation of pilot jobs, that we dubbed Pilots 2.0. Pilots 2.0 are not tied to a specific infrastructure; rather they are generic, fully configurable and extendible pilots. A Pilot 2.0 can be sent, as a script to be run, or it can be fetched from a remote location. A pilot 2.0 can run on every computing resource, e.g.: on CREAM Computing elements, on DIRAC Computing elements, on Virtual Machines as part of the contextualization script, or IAAC resources, provided that these machines are properly configured, hiding all the details of the Worker Nodes (WNs) infrastructure. Pilots 2.0 can be generated server and client side. Pilots 2.0 are the “pilots to fly in all the skies”, aiming at easy use of computing power, in whatever form it is presented. Another aim is the unification and simplification of the monitoring infrastructure for all kinds of computing resources, by using pilots as a network of distributed sensors coordinated by a central resource monitoring system. Pilots 2.0 have been developed using the command pattern. VOs using DIRAC can tune pilots 2.0 as they need, and extend or replace each and every pilot command in an easy way. In this

  5. Politische Bildung und das Web 2.0

    Directory of Open Access Journals (Sweden)

    Heike Schaumburg

    2011-08-01

    Full Text Available Aktuell erhält die Diskussion um die Rolle des Internet in der Politischen Bildung neuen Auftrieb durch die Entwicklung der sogenannten Web-2.0- Technologien, die im Vergleich zum Web 1.0 ein erheblich grösseres Potenzial zur Mitgestaltung politischer Inhalte und Prozesse und bzw. zur Partizipation bieten, aber auch neue Möglichkeiten der Kommunikation und Vernetzung eröffnen. In der vorliegenden Studie wird der Frage nachgegangen, inwieweit das Internet und speziell das Web 2.0 in der Lage sind, die in die Technik gesetzten Hoffnungen zu erfüllen. Dabei wird zunächst ausgelotet, welche Potenziale das Web 2.0 für die Politische Bildung mit Blick auf ihre didaktische Gestaltung bieten könnte. Im Anschluss daran wird auf der Basis einer Analyse des Internet-Angebots der traditionellen Anbieter Politischer Bildung (Bundes- und Landeszentralen für Politische Bildung, politische Stiftungen sowie von Internetportalen im Bereich Politische Bildung festgestellt, welche Verbreitung Web-2.0-Angebote gegenwärtig besitzen. Schliesslich wird auf der Grundlage einer Nutzerbefragung an knapp 300 Teilnehmern virtueller politischer Bildungsangebote einer politischen Stiftung der Frage nachgegangen, wie Web-2.0-Angebote in der Politischen Bildungsarbeit aus Nutzersicht beurteilt werden.

  6. Web 2.0 in e-Learning

    Directory of Open Access Journals (Sweden)

    M. Tariq Banday

    2013-10-01

    Full Text Available Web 2.0 tools have created fresh opportunities for governments, education, businesses and individuals to enhance efficiency and improve effectiveness while executing respective professional duties. The key features of these tools include online character and access through a web browser, supportive for open content licenses, open sharing and social interaction, and often free to use or support free features. These have created novel prospects for teachers to combine face-to-face teaching and online materials via social media such as discussion forums, blogs and wikis. The web 2.0 educational design is based on socio-cultural learning theories such as interaction, joint creation of content, critical thinking, learning by doing and collaboration. This paper makes an appraisal of ICT adoption in education, emergence of Web, improvements in Web and its effect on the e-Learning. It explains gradual integration of ICT into education through various stages. The paper presents the content and communication dimensions of e-learning for its classification. It discusses various opportunities created by Web 2.0 tools in education for effective teacher-learner, learner-learner and teacher-teacher communication, interaction and collaboration. It presents various cases and projects involving use of some Web 2.0 tools for enhancing learning. Furthermore, it lists some challenges for successful implementation of e-learning through Web 2.0 tools and discusses some possible solutions for its control.

  7. Measurements of proton induced γ-ray emission cross sections on MgF{sub 2} target in the energy range 1.95–3.05 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Zamboni, I., E-mail: izamboni@irb.hr; Siketić, Z.; Jakšić, M.; Bogdanović Radović, I.

    2015-01-01

    Highlights: • We measured PIGE differential cross sections for F and Mg between 1.95 and 3.05 MeV with 15 keV step. • In general good agreement was found with the data available from the literature. • We observed resonance in the {sup 24}Mg(p,pγ{sub 1−0}){sup 24}Mg reaction at 2.01 MeV, which is well-suited for depth profiling of Mg. - Abstract: In this work we present differential cross sections for γ-ray emission from the reactions {sup 19}F(p,p′γ){sup 19}F (E{sub γ} = 110, 197, 1236 and 1349 + 1357 keV), {sup 24}Mg(p,p′γ){sup 24}Mg (E{sub γ} = 1369 keV) and {sup 25}Mg(p,p′γ){sup 25}Mg (E{sub γ} = 390, 585 and 975 keV). Differential cross sections were measured for proton energies from 1.95 to 3.05 MeV with a 15 keV step and beam energy resolution of 0.06%. Thin reference standard, 54.1 μg/cm{sup 2} of MgF{sub 2} deposited on thin Mylar foil with additionally evaporated 4 nm Au layer, was used as a target. The γ-rays were detected by a 20% relative efficiency HPGe detector placed at an angle of 135° with respect to the beam direction, while the backscattered protons were collected using silicon surface barrier detector placed at the scattering angle of 165°. Obtained cross sections were compared with the previously measured data available from the literature.

  8. 20 CFR 227.2 - Initial supplemental annuity rate.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Initial supplemental annuity rate. 227.2... COMPUTING SUPPLEMENTAL ANNUITIES § 227.2 Initial supplemental annuity rate. The supplemental annuity rate, before reduction for the railroad retirement family maximum or any private pension, is $23 for...

  9. 20 CFR 606.2 - Total credits allowable.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Total credits allowable. 606.2 Section 606.2 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR TAX CREDITS UNDER THE... credits allowable. The total credits allowed to an employer subject to the tax imposed by section 3301 of...

  10. Incorporating Web 2.0 Technologies from an Organizational Perspective

    Science.gov (United States)

    Owens, R.

    2009-12-01

    The Arctic Research Consortium of the United States (ARCUS) provides support for the organization, facilitation, and dissemination of online educational and scientific materials and information to a wide range of stakeholders. ARCUS is currently weaving the fabric of Web 2.0 technologies—web development featuring interactive information sharing and user-centered design—into its structure, both as a tool for information management and for educational outreach. The importance of planning, developing, and maintaining a cohesive online platform in order to integrate data storage and dissemination will be discussed in this presentation, as well as some specific open source technologies and tools currently available, including: ○ Content Management: Any system set up to manage the content of web sites and services. Drupal is a content management system, built in a modular fashion allowing for a powerful set of features including, but not limited to weblogs, forums, event calendars, polling, and more. ○ Faceted Search: Combined with full text indexing, faceted searching allows site visitors to locate information quickly and then provides a set of 'filters' with which to narrow the search results. Apache Solr is a search server with a web-services like API (Application programming interface) that has built in support for faceted searching. ○ Semantic Web: The semantic web refers to the ongoing evolution of the World Wide Web as it begins to incorporate semantic components, which aid in processing requests. OpenCalais is a web service that uses natural language processing, along with other methods, in order to extract meaningful 'tags' from your content. This metadata can then be used to connect people, places, and things throughout your website, enriching the surfing experience for the end user. ○ Web Widgets: A web widget is a portable 'piece of code' that can be embedded easily into web pages by an end user. Timeline is a widget developed as part of the

  11. Mobile Web 2.0 Developing and Delivering Services to Mobile Devices

    CERN Document Server

    Ahson, Syed A

    2010-01-01

    From basic concepts to research grade material, Mobile Web 2.0: Developing and Delivering Services to Mobile Devices provides complete and up-to-date coverage of the range of technical topics related to Mobile Web 2.0. It brings together the work of 51 pioneering experts from around the world who identify the major challenges in Mobile Web 2.0 applications and provide authoritative insight into many of their own innovations and advances in the field. To help you address contemporary challenges, the text details a conceptual framework that provides modeling facilities for context-aware, multi-c

  12. From Zero to Web 2.0: Part 2

    Science.gov (United States)

    Woodard, Amber

    2009-01-01

    During the summer semester, the Vise Library at Cumberland University (CU) began working on its "digital makeover." It has six goals: (1) Create a more user-friendly and dynamic website; (2) Activate and maintain accounts on social networking sites such as Facebook, MySpace, and Twitter; (3) Produce a library blog that allows students, staff, and…

  13. Use of Web 2.0 tools by hospital pharmacists

    Directory of Open Access Journals (Sweden)

    B. Bonaga Serrano

    2014-03-01

    Full Text Available Objective: Web 2.0 tools are transforming the pathways health professionals use to communicate among themselves and with their patients so this situation forces a change of mind to implement them. The aim of our study is to assess the state of knowledge of the main Web 2.0 applications and how are used in a sample of hospital pharmacists. Method: The study was carried out through an anonymous survey to all members of the Spanish Society of Hospital Pharmacy (SEFH by means of a questionnaire sent by the Google Drive® application. After the 3-month study period was completed, collected data were compiled and then analyzed using SPPS v15.0. Results: The response rate was 7.3%, being 70.5% female and 76.3% specialists. The majority of respondents (54.2% were aged 20 to 35. Pubmed was the main way of accessing published articles. 65.2% of pharmacists knew the term “Web 2.0”. 45.3% pharmacists were Twitter users and over 58.9% mainly for professional purposes. Most pharmacists believed that Twitter was a good tool to interact with professionals and patients. 78.7% do not use an agregator, but when used, Google Reader was the most common. Conclusion: Although Web 2.0 applications are gaining mainstream popularity some health professionals may resist using them. In fact, more than a half of surveyed pharmacists referred a lack of knowledge about Web 2.0 tools. It would be positive for pharmacists to use them properly during their professional practice to get the best out of them.

  14. Development and application of GASP 2.0

    Science.gov (United States)

    Mcgrory, W. D.; Huebner, L. D.; Slack, D. C.; Walters, R. W.

    1992-01-01

    GASP 2.0 represents a major new release of the computational fluid dynamics code in wide use by the aerospace community. The authors have spent the last two years analyzing the strengths and weaknesses of the previous version of the finite-rate chemistry, Navier Stokes solution algorithm. What has resulted is a completely redesigned computer code that offers two to four times the performance of previous versions while requiring as little as one quarter of the memory requirements. In addition to the improvements in efficiency over the original code, Version 2.0 contains many new features. A brief discussion of the improvements made to GASP, and an application using GASP 2.0 which demonstrates some of the new features are presented.

  15. Significance of Web 2.0 in Digital Libraries

    Directory of Open Access Journals (Sweden)

    Hanumat G. Sastry,

    2010-09-01

    Full Text Available The rapid development of Information and Communication Technologies has provided a well sophisticated environment to develop the digital libraries. A digital library is a large-scale, organized collection of complex and dynamic multimedia information and knowledge, and tools and methods to enable search, manipulation and presentation of this information and knowledge via Internet. User-Centered approach for the digital libraries would increase its usage [1]. Web 2.0 technologies provide better user-centered services with rich user experience for Web applications. Hence this paper deals with the significance of Web 2.0 in building of digital libraries and presents the architecture of Web 2.0 enabled user interface system for DSpace digital repository.

  16. WEB 2.0 Social Network Sites and Facebook Marketing

    Directory of Open Access Journals (Sweden)

    Andreas Chang

    2011-10-01

    Full Text Available The use of Web 2.0 and Social Network Sites (SNS has become an amazing phenomenon. In fact, one of the fastest-growing arenas of the World Wide Web is the space of so-called social networking sites. Face book, Tweeter, MySpace and other Social Network Sites have huge population of users. Almost seven hundred million people use Facebook, and hundreds of million others use other social networking sites. More and more advertisers switch their marketing budget to these SNS. This study contributes to our understanding of the Web 2.0 and the use of social networking websites by examining available literature. It seeks to understand what Web 2.0 and SNS mean, the trends, its functions and how they can be leveraged for marketing purposes.

  17. Web 2.0 Socail Network Sites And Facebook Marketing

    Directory of Open Access Journals (Sweden)

    Andreas Chang

    2011-11-01

    Full Text Available The use of Web 2.0 and Social Network Sites (SNS has become an amazing phenomenon. In fact, one of the fastest-growing arenas of the World Wide Web is the space of so-called social networking sites. Face book, Tweeter, MySpace and other Social Network Sites have huge population of users. Almost seven hundred million people use Facebook, and hundreds of million others use other social networking sites. More and more advertisers switch their marketing budget to these SNS. This study contributes to our understanding of the Web 2.0 and the use of social networking websites by examining available literature. It seeks to understand what Web 2.0 and SNS mean, the trends, its functions and how they can be leveraged for marketing purposes.

  18. Web2.0与药学教育

    Institute of Scientific and Technical Information of China (English)

    Cain J; Fox B I; 边玲

    2010-01-01

    @@ Web 2.0应用程序如blogs、Faeebook、YouTube等正迅速覆盖寻求社交和互动的人们,这些技术也具备应用到高等教育中的价值,方便人们交流和分享知识.许多Web 2.0应用程序纳入教育环境的门槛低,大部分申请免费提供,可随时通过互联网访问,并且不需要过多技术技能.本文为教育工作者介绍各种Web 2.0应用程序及其在药学教育中的潜在用途.

  19. Status report on a dc 130-mA, 75-keV proton injector

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, J.; Arvin, A.; Hodgkins, D. [and others

    1997-10-01

    A 110-mA, 75-keV dc proton injector is being developed at Los Alamos. We use a microwave proton source coupled to a two solenoid, space-charge neutralized, low-energy beam transport (LEBT) system. The ion source produces 110-mA proton current at 75 keV using 600 - 800 W of 2.45 GHz input discharge power. Typical proton fraction is 85-90% of the total extracted ion current, and the rms normalized beam emittance after transport through a prototype 2.1 m LEBT is 0.20 ({pi}mm-mrad). Beam space-charge neutralization is measured to be > 98% which enables the solenoid magnetic transport to successfully match the injector beam into a radio-frequency quadrupole (RFQ). Beam simulations indicate small emittance growth in the proposed 2.8 m low-energy demonstration accelerator (LEDA) LEBT. The LEBT also contains beam diagnostics, steering, and a beam deflector for variable duty factor and accelerator fast protect functions. The injector computer controls and reliability status are also discussed.

  20. Semantic web technologies for enterprise 2.0

    CERN Document Server

    Passant, A

    2010-01-01

    In this book, we detail different theories, methods and implementations combining Web 2.0 paradigms and Semantic Web technologies in Enterprise environments. After introducing those terms, we present the current shortcomings of tools such as blogs and wikis as well as tagging practices in an Enterprise 2.0 context. We define the SemSLATES methodology and the global vision of a middleware architecture based on Semantic Web technologies and Linked Data principles (languages, models, tools and protocols) to solve these issues. Then, we detail the various ontologies that we build to achieve this g