WorldWideScience

Sample records for 2 20 kev range

  1. Characterisation of a counting imaging detector for electron detection in the energy range 10-20 keV

    Energy Technology Data Exchange (ETDEWEB)

    Moldovan, G., E-mail: grigore.moldovan@materials.ox.ac.uk [University of Oxford, Department of Materials, Parks Road, Oxford OX1 3PH (United Kingdom); Sikharulidze, I. [Leiden University, Leiden Institute of Chemistry, P.O. Box 9502, 2300RA Leiden (Netherlands); Matheson, J.; Derbyshire, G. [Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX (United Kingdom); Kirkland, A.I. [University of Oxford, Department of Materials, Parks Road, Oxford OX1 3PH (United Kingdom); Abrahams, J.P. [Leiden University, Leiden Institute of Chemistry, P.O. Box 9502, 2300RA Leiden (Netherlands)

    2012-07-21

    As part of a feasibility study into the use of novel electron detector for X-ray photoelectron emission microscopes (XPEEM) and related methods, we have characterised the imaging performance of a counting Medipix 2 readout chip bump bonded to a Silicon diode array sensor and directly exposed to electrons in the energy range 10-20 keV. Detective Quantum Efficiency (DQE), Modulation Transfer Function (MTF) and Noise Power Spectra (NPS) are presented, demonstrating very good performance for the case of electrons with an energy of 20 keV. Significant reductions in DQE are observed for electrons with energy of 15 keV and less, down to levels of 20% for electrons of 10 keV.

  2. 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.

  3. Characterisation of a detector based on microchannel plates for electrons in the energy range 10-20 keV

    Energy Technology Data Exchange (ETDEWEB)

    Moldovan, G. [Department of Materials, University of Oxford, Parks Road, Oxford, Oxon OX1 3PH (United Kingdom)], E-mail: grigore.moldovan@materials.ox.ac.uk; Matheson, J.; Derbyshire, G. [Rutherford Appleton Laboratory, Science and Technology Facilities Council, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Kirkland, A. [Department of Materials, University of Oxford, Parks Road, Oxford, Oxon OX1 3PH (United Kingdom)

    2008-11-11

    As part of a feasibility study into the use of novel electron detectors for an X-ray photoelectron emission microscope (XPEEM), we have characterised a detector based on microchannel plates (MCPs), a phosphor screen and a CCD camera. For XPEEM, an imaging detector is required for electrons in the energy range 10-20 keV. This type of detector is a standard fitment on commercial instruments and we have studied its performance in some detail in order to provide a baseline against which to evaluate future detector technologies. We present detective quantum efficiency (DQE), noise power spectrum (NPS) and modulation transfer function (MTF) measurements of a commercial detector, in the energy range of interest, as a function of the detector bias voltage.

  4. 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.

  5. 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.

  6. Studies on effective atomic numbers for photon energy absorption and electron density of some narcotic drugs in the energy range 1 keV-20 MeV

    Science.gov (United States)

    Gounhalli, Shivraj G.; Shantappa, Anil; Hanagodimath, S. M.

    2013-04-01

    Effective atomic numbers for photon energy absorption ZPEA,eff, photon interaction ZPI,eff and for electron density Nel, have been calculated by a direct method in the photon-energy region from 1 keV to 20 MeV for narcotic drugs, such as Heroin (H), Cocaine (CO), Caffeine (CA), Tetrahydrocannabinol (THC), Cannabinol (CBD), Tetrahydrocannabivarin (THCV). The ZPEA,eff, ZPI,eff and Nel values have been found to change with energy and composition of the narcotic drugs. The energy dependence ZPEA,eff, ZPI,eff and Nel is shown graphically. The maximum difference between the values of ZPEA,eff, and ZPI,eff occurs at 30 keV and the significant difference of 2 to 33% for the energy region 5-100 keV for all drugs. The reason for these differences is discussed.

  7. 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).

  8. 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

    International Nuclear Information System (INIS)

    The average 235U 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

  9. 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.

  10. 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.

  11. Study on absolute sensitivity of X-ray electron-optical converter in the energy range of 7-20 keV

    International Nuclear Information System (INIS)

    Absolute spectral sensitivity of X-ray electron-optical converter (XREOC) with the beryllium window and a microchannel plate as a converting and amplifying element for the 7-20 keV X-ray range, was measured. Measurements were performed in the VEhPP-3M storage ring synchrotron radiation channel. It is shown that in the energy range indicated the ratio of photon number in the blue spectrum region at the XREOC outlet to the number of X-ray quanta at the inlet grows from 1200 up to 2200 photons per a quantum. Sensitivity change over the XREOC operating field is investigated

  12. 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.

  13. Observations of the scatter-free solar-flare electrons in the energy range 20-1000 keV

    Science.gov (United States)

    Wang, J. R.; Fisk, L. A.; Lin, R. P.

    1971-01-01

    Observations of the scatter-free electron events from solar active region McMath No. 8905 are presented. The measurements were made on Explorer 33 satellite. The data show that more than 80% of the electrons from these events undergo no or little scattering and that these electrons travel only approximately 1.5 a.u. between the sun and the earth. The duration of these events cannot be accounted fully by velocity dispersion alone. It is suggested that these electrons could be continuously injected into interplanetary medium for a time interval of approximately 2 to 3 minutes. Energy spectra of these electrons are discussed.

  14. 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.

  15. 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...

  16. Plasma X-ray emission in the 20-500 keV range during lower hybrid current drive on Alcator

    International Nuclear Information System (INIS)

    An array of eight 1'' x 3'' NaI scintillators has been used to collect plasma hard x-ray spectra (E/sub γ/>20 keV) emitted perpendicular to the magnetic axis during lower hybrid current drive on Alcator. The spectra exhibit a tail extending out to at least 300 keV and the profiles are generally peaked. These results show that the slope of the x-ray spectra increases with increasing plasma radius. Equivalently, the emission profiles tend to broaden with increasing photon energy. Also, the x-ray spectra slope increases at each radial location as the relative phasing of adjacent waveguides in the grill antenna is decreased. Preliminary results also suggest that the x-ray spectra tend to flatten and that the emission profiles tend to peak up with decreasing plasma density or increasing magnetic field. In addition, the initial results of an array for measuring the high energy x-ray emission from Alcator as a function of the emission angle relative to the magnetic axis are presented

  17. 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....

  18. Soft x-ray (0.22.0 keV) imager for z-pinch plasma radiation sources

    Science.gov (United States)

    Failor, B. H.; Qi, N.; Levine, J. S.; Sze, H.; Gullickson, E. M.

    2004-10-01

    Z-pinches can produce intense fluxes of argon K-shell (3 keV) radiation, but typically only a fraction of the load mass near the axis of the pinch radiates in this spectral range. The majority of the mass does not get hot or dense enough to radiate efficiently in the K-shell. We have designed, built, and tested an instrument to image pinch emission, specifically the radial emission profile, at energies below the K-shell in order to track the location of the cooler mass. A gold mirror provides a high-energy cut-off at 2 keV while a transmission grating disperses the incoming radiation and provides a low-energy cutoff at 0.1 keV. A vertical slit images the pinch radiation in the radial direction and the emission profile is recorded with either an extreme ultraviolet-sensitive charge-coupled device camera (time-integrated) or a linear photodiode array (˜1 ns time resolution). We present results for the mirror, grating, and system characterization obtained at the Advanced Light Source synchrotron located at Lawrence Berkeley National Laboratory (Berkeley, CA).

  19. Reduction in the intensity of solar X-ray emission in the 2- to 15-keV photon energy range and heating of the solar corona

    Energy Technology Data Exchange (ETDEWEB)

    Mirzoeva, I. K., E-mail: colombo2006@mail.ru [Russian Academy of Sciences, Space Research Institute (Russian Federation)

    2013-04-15

    The time profiles of the energy spectra of low-intensity flares and the structure of the thermal background of the soft X-ray component of solar corona emission over the period of January-February, 2003, are investigated using the data of the RHESSI project. A reduction in the intensity of X-ray emission of the solar flares and the corona thermal background in the 2- to 15-keV photon energy range is revealed. The RHESSI data are compared with the data from the Interball-Geotail project. A new mechanism of solar corona heating is proposed on the basis of the results obtained.

  20. Investigation of Methanol Formation Mechanisms in H2O+CH4 Ices Subjected to 5 keV Electrons at a 10-100 K Temperature Range

    Science.gov (United States)

    Stelmach, K. B.; Cooper, P. D.

    2014-12-01

    Methane (CH4) and water are one of the most common molecules in both planetary bodies and interstellar dust grains. Another common molecule, methanol (CH3OH), is thought to form in CH4+H2O ices. However, the exact formation mechanisms of methanol from cosmic rays are not well known, especially in the temperatures of interest. Experiments were performed using high energy electrons (5 keV) to irradiate mixtures of 1:10, 1:5, and 1:3 CH4+H2O ices under a temperature range of 10-100 Kelvin with Fourier Transform Infrared (FTIR) spectroscopy being used to identify the products. Isotopologues of the two molecules (D2O and CD4) were used to probe for the mechanisms. Other products were formed as well and their potential mechanisms are identified. The implications of the mechanisms for planetary and interstellar chemistry are discussed.

  1. Studies of Transport Properties and Critical Temperature Suppression Mechanism in Yttrium BARIUM(2) COPPER(3) Oxygen(x) Thin Films Irradiated with 20 TO 120 KEV Electrons

    Science.gov (United States)

    Lin, Jiunn-Yuan

    1995-11-01

    We present comprehensive studies of the effects of 20 to 120 keV electron irradiation on rm YBa_2Cu_3O_{x} thin films. Above 60 keV, T_{c } of irradiated samples is suppressed accompanied by a significant increase in residual resistivity, while the carrier concentration remains relatively unchanged. The plane oxygen defects produced by irradiation are found to be responsible for T_{c} suppression. The II suppression mechanism is discussed within several theoretical frameworks. Though in qualitative agreement with d-wave pairing symmetry, our results show a T_{c} suppression rate three times as slow as predicted by the theory when resistivity data are used to extract the impurity scattering rate. Alternatively, phase fluctuations theory gives a qualitative description as well. The displacement energy of plane oxygen is found to be 8.3 eV, which corresponds to a threshold electron energy 58 keV. Finally, an empirical relation is proposed to describe the temperature dependence of the Hall coefficient.

  2. 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.

  3. 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...

  4. 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....

  5. 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.

  6. 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......, linolenic, arachidonic, and arachidic acids), nucleotide bases (adenine, guanine, cytosine, uracil, and thymine), and carbohydrates (glucose, sucrose, raffinose, and starch). The Z(PEA, eff) and Z(PI, eff) values have been found to change with energy and composition of the biological molecules. The energy...

  7. 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.

  8. 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.

  9. 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.

  10. Differential cross sections for γγ->panti p in the C.M. energy range from 2.0 to 3.1 GeV

    International Nuclear Information System (INIS)

    Exclusive production of proton-antiproton pairs by two photon scattering at c.m. energies between 2.0 GeV and 3.1 GeV has been measured with the TASSO detector at the e+e- storage ring PETRA. The angular distribution is flat within the accepted c.m. angular range vertical strokecosTHETAsup(*)vertical strokeγγ)xB(etasub(c)->panti p)<0.32 keV (95% c.l.) is found. (orig.)

  11. 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.

  12. 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.

  13. Electron capture by 20-150 keV protons on hydrocarbon gases

    International Nuclear Information System (INIS)

    Cross sections are reported for electron capture by 20-150 keV protons incident on CO, CH4, C2H6, and C3H8 target gases. These cross sections were obtained from a new system which measures the proton flux prior to entering and immediately after leaving a differentially pumped gas cell. The absolute magnitude and energy dependence of the values obtained from this apparatus compare favorably with existing measurements where such values are available, the C3H8 values are new to the literature. Attempts to reconcile the hydrocarbon data in terms of generalized additive rules have met with limited success below 70 keV but fail as the projectile velocity increases. (orig.)

  14. 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.

  15. 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.

  16. MEDIUM-RANGE ORDER CLUSTERS IN Fe-2.0%C ALLOY MELT

    Institute of Scientific and Technical Information of China (English)

    X.B. Qin; S.J. Cheng; X.F. Bian

    2003-01-01

    The structure of Fe-2.0%C alloy melt was investigated at 1580, 1560, 1540 and 1450℃ by using an X-ray diffractometer respectively. The results showed that with decreasing temperature, the average atoms of cluster, the coordination numbers, the correlation radius and the atom density increased, whereas the pre-peak of the structure factors curve remained almost at the same position. The appearance of the pre-peak indicated that the liquid structure and the solid structure of the Fe-2.0%C alloy were correlated.

  17. Inelastic processes in K^(+)- He collisions in energy range 0.7 - 10 keV

    CERN Document Server

    Lomsadze, R A; Kezerashvili, R Ya; Mosulishvili, N O; Phaneuf, R

    2013-01-01

    Absolute cross sections for charge exchange, ionization, stripping and excitation in K^(+) - He collisions were measured in the ion energy range 0.7 - 10 keV. The experimental data and the schematic correlation diagrams are used to analyze and determine the mechanisms for these processes. The increase of the excitation probability of inelastic channels with the angle of scattering is revealed. An exceptionally highly excited state of He is observed and a peculiarity for the excitation function of the resonance line is explained. The intensity ratio for the excitation of the K II \\lambda = 60.1 nm and \\lambda = 61.2 nm lines is 5:1 which indicates the high probability for excitation of the singlet resonance level $^{1}$P$_{1}$ compared to the triplet level $^{3}$P$_{1}$. The similarity of the population of the 4p state of the potassium ion and atom as well as the anomalously small values of the excitation cross sections are explained.

  18. 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.

  19. Measurement of Fission Cross-Sections for Neutrons of Energies in the Range 40-500 keV

    International Nuclear Information System (INIS)

    Measurements have been made of the fission cross-section of U233, U234 , U236, Np237, Pu239 and Pu241 at several neutron energies between 40 keV and 500 keV. Measurements in this energy range are of importance in reactor calculations especially in fast dilute systems where the neutron flux is high in the 10- 100-keV energy range. Recent measurements at this laboratory of the U235 fission cross-section gave absolute values slightly lower than previous data. The present series of measurements are made relative to the new values of the U235 fission cross-section using back-to-back ionization chambers. The fissile foils were assayed by α-assay, direct weighing and coulometry. Good agreement was obtained between these assays. The fission measurements have an estimated accuracy of between 1 % and.2% and,combined with the, error on the U235 fission cross-section,give a final error of about 3% in the fission cross-sections. The present results together with those of previous measurements are given, and the corrections for fission- fragment absorption, backgrounds and scattering are discussed. (author)

  20. PET surface modification by 0.2 keV and 2.5 keV argon ions

    International Nuclear Information System (INIS)

    PET foils have a high potential as a material for biomedical and electrical industries. PET foils were irradiated by ions for variable irradiation time. The effects of low (2.5, 0.2 keV) energy argon ion flux irradiation on the surfaces of polyethylene terephthalate thin foils (PET) were studied. The source of ions was an ECR Ion Gun with settable acceleration voltages. The modified foils were investigated by in-situ X-ray Photoelectron Spectroscopy (XPS) and ex-situ Fourier transform infrared spectroscopy (FTIR). The significant changes in the chemical composition of the surface layer were quantitatively studied by XPS. The scission of the chains in the surface layer of PET foil was induced by ion flux interaction with PET surface. The strong selective sputtering of oxygen atoms in PET film was observed. The atomic ratio O/C was decreased by 0.2keV and 2.5keV argon ion flux from 0.40 to 0.25 and 0.04 respectively. The oxygen atoms in ester bonds are detached first. This phenomenon is responsible for the creation of carbon-rich surface layer. The FTIR analyses identified changes in chemical composition but with no obvious correlation to surface changes. PET volume changes in the spectra were probably results of photons from the ion source influence on PET foils.

  1. Re-measurement of the neutron-induced gamma-ray production cross sections for iron in the energy range 850 keV less than or equal to E/sub n/ less than or equal to 20. 0 MeV. [Tables

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, G.T.; Morgan, G.L.; Perey, F.G.

    1976-07-01

    Values of the gamma-ray production cross sections for neutron interactions with iron as reported by previous investigators have differed by as much as a factor of 1.5 or more at neutron energies greater than about 5 MeV. Because of this discrepancy, the measurements were repeated at ORNL using the ORELA as a pulsed source of neutrons with energies between 850 keV and 20 MeV. The data were obtained using a NaI(Tl) gamma-ray spectrometer oriented at an angle of 125/sup 0/ to the incident neutron beam. The sample was positioned in the beam at a distance of 47.35 meters from the neutron source. The resulting data, presented as differential cross sections (d/sup 2/sigma/d..cap omega..dE) for gamma rays between 0.7 and 10.5 MeV, show good agreement with some previously published data, but are significantly different from previous ORNL measurements for neutron energies greater than 5 MeV.

  2. Experimental determination of sensitivity of DN-A-1 dosimeter and 6LiJ(Eu) scintillation detector in sphere polyethylene moderators in the 30 keV neutron energy range

    International Nuclear Information System (INIS)

    DH-A-1 dosimeter and 6LiJ(Eu) detector, located in the center of polyethylene spheres with various diameters, were calibrated by means of neutrons with the energy of about 30 keV. The data on the detectors responses enable one to determine the shape of responses as a function of neutron energy more definitely at the energy range from some keV to some tens of keV. For DN-A-1 dosimeter response at neutrons and at neutrons in the energy range of about 30 keV the agreement is better than the uncertainties of measurements (about 20%)

  3. L-shell ionization of Sn and Gd by 20 - 100 keV electron impact

    International Nuclear Information System (INIS)

    Measurements have been made of the relative x-ray production cross section Lsub(α)/Lsub(γ), Lsub(α)/Lsub(β) and Lsub(α)/Lsub(l) using electrons of energy 20 to 100 keV incident on thin targets of tin and gadolinium. The experimental ratios obtained have been compared with theoretical values. Modification of these ratios due to the formation of double vacancy atomic states has been calculated, but this effect on its own is not sufficient to account for the discrepancy between theory and experimental results

  4. Microchannel plate pinhole camera for 20 to 100 keV x-ray imaging

    International Nuclear Information System (INIS)

    We present the design and construction of a sensitive pinhole camera for imaging suprathermal x-rays. Our device is a pinhole camera consisting of four filtered pinholes and microchannel plate electron multiplier for x-ray detection and signal amplification. We report successful imaging of 20, 45, 70, and 100 keV x-ray emissions from the fusion targets at our Novette laser facility. Such imaging reveals features of the transport of hot electrons and provides views deep inside the target

  5. Study of pp interactions in the momentum range 0.9 to 2.0 GeV/c

    Science.gov (United States)

    Shimizu, F.; Koiso, H.; Kubota, Y.; Sai, F.; Sakamoto, S.; Yamamoto, S. S.

    1982-11-01

    pp interactions at 11 momenta in the range 0.9 to 2.0 GeV/ c have been studied. The elastic angular distributions, covering the c.m. angular range 22°-90°, agree in general with Hoshizaki's phase-shift analysis which shows the looping 1D in and 3F 3 amplitudes in the Argand diagram. About 80% of pn π+ events come from the n Δ++ state at all momenta above 1.2 GeV/ c. The behavior of the density matrix elements of the Δ++ show no momentum or angular dependence. A large fraction of pp π0 events also come from the p Δ+ state at all momenta above 1.2 GeV/ c. The behavior of the Δ+ density matrix elements is similar to that for the case of Δ++.

  6. Effective atomic numbers and electron densities of some biologically important compounds containing H, C, N and O in the energy range 145 1330 keV

    Science.gov (United States)

    Manjunathaguru, V.; Umesh, T. K.

    2006-09-01

    A semi-empirical relation which can be used to determine the total attenuation cross sections of samples containing H, C, N and O in the energy range 145-1332 keV has been derived based on the total attenuation cross sections of several sugars, amino acids and fatty acids. The cross sections have been measured by performing transmission experiments in a narrow beam good geometry set-up by employing a high-resolution hyperpure germanium detector at seven energies of biological importance such as 145.4 keV, 279.2 keV, 514 keV, 661.6 keV, 1115.5 keV, 1173.2 keV and 1332.1 keV. The semi-empirical relation can reproduce the experimental values within 1-2%. The total attenuation cross sections of five elements carbon, aluminium, titanium, copper and zirconium measured in the same experimental set-up at the energies mentioned above have been used in a new matrix method to evaluate the effective atomic numbers and the effective electron densities of samples such as cholesterol, fatty acids, sugars and amino acids containing H, C, N and O atoms from their effective atomic cross sections. The effective atomic cross sections are the total attenuation cross sections divided by the total number of atoms of all types in a particular sample. Further, a quantity called the effective atomic weight was defined as the ratio of the molecular weight of a sample to the total number of atoms of all types in it. The variation of the effective atomic number was systematically studied with respect to the effective atomic weight and a new semi-empirical relation for Zeff has been evolved. It is felt that this relation can be very useful to determine the effective atomic number of any sample having H, C, N and O atoms in the energy range 145-1332 keV irrespective of its chemical structure.

  7. Energy dependence of some neutron dosimeter sensitivities in the 1 ev up to 4 kev energy range

    International Nuclear Information System (INIS)

    The sensitivities of DN-A-1 device and SNM-14 slow neutron counter with a combined moderator in the 1 eV up to 4 keV energy range has been experimentally determined. The IBR-30 reactor served as a neutron source, spectral distribution was performed by the time-of-flight method. The sensitivity constancy of a long counter in the 1 eV up to 4 keV energy range has been experimentally shown. The obtained sensitivity values and other data available could be used in determining energy dependencies of the device sensitivity in essential neutron energy range. It permits to evaluate their errors when using as dosimeters in radiation fields of nuclear physics installations

  8. Formation of dot arrays with a pitch of 20 nm x 20 nm for patterned media using 30 keV EB drawing on thin calixarene resist

    Energy Technology Data Exchange (ETDEWEB)

    Mohamad, Zulfakri bin [Department of Nano-Material System, Graduate School of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Shirai, Masumi [Department of Nano-Material System, Graduate School of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Sone, Hayato [Department of Production Science and Technology, Graduate School of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Hosaka, Sumio [Department of Production Science and Technology, Graduate School of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Kodera, Masatoshi [Department of Electronics, Information and Communication Engineering, Osaka Institute of Technology, 5-16-1 Omiya, Asahi-ku, Osaka 535-8585 (Japan)

    2008-01-16

    We studied the possibility of achieving very fine-pitch dot arrays with a pitch of 20 nm x 20 nm using 30 keV electron beam (EB) drawing on negative calixarene resist. In order to form such patterns, we studied the dependence on resist thickness of the dot size and the packing. We propose EB drawing on an extremely thin film for very highly packed dot-array formation. Our experimental results demonstrate the possibility of forming highly packed dot-array patterns with a pitch of 20 nm x 20 nm and a resist thickness of about 13 nm, which corresponds to about 1.6 Tbits in{sup -2}.

  9. 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

  10. Simultaneous solution of Kompaneets equation and radiative transfer equation in the photon energy range 1-125 keV

    International Nuclear Information System (INIS)

    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 are 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, n2 and (∂n/∂xk) where n is photon phase density and xk=(hν/kTe), in Kompaneets equation and those due to free-free emission are utilized to calculate the change in the photon phase density in a hot electron gas. Two types of incident radiation are considered: (1) isotropic radiation with the modified black body radiation IMB and (2) anisotropic radiation which is angle dependent. The emergent radiation at τ=0 and reflected radiation τ=τmax are calculated by using the diffuse radiation from the medium. The emergent and reflected radiation contain the free-free emission and emission from the hot electron gas. Kompaneets equation gives the changes in photon phase densities in different types of media. Although the initial spectrum is angle dependent, the Kompaneets equation gives a spectrum which is angle independent after several Compton scattering times.

  11. Facilities and techniques for x-ray diagnostic calibration in the 100-eV to 100-keV energy range

    International Nuclear Information System (INIS)

    The Lawrence Livermore National Laboratory (LLNL) has been a pioneer in the field of x-ray diagnostic calibration for more than 20 years. We have built steady state x-ray sources capable of supplying fluorescent lines of high spectral purity in the 100-eV to 100-keV energy range, and these sources have been used in the calibration of x-ray detectors, mirrors, crystals, filters, and film. This paper discusses our calibration philosophy and techniques, and describes some of our x-ray sources. Examples of actual calibration data are presented as well

  12. 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...

  13. Creation of 2-5 keV and 5-10 keV sky maps using XMM-Newton data

    CERN Document Server

    Savchenko, Denis

    2014-01-01

    Sky maps are powerful visualisation tools for quicklook analysis of extended sources. The latest sky map in soft X-rays (0.1-2.4 keV) has been created in 90ies using ROSAT data. By analyzing publically available data from XMM-Newton X-ray mission we constructed new sky maps in two energy bands -- 2-5 keV and 5-10 keV, complementary to ROSAT data, covering about 1% of all sky, and included them to our web-based tool http://skyview.virgoua.org.

  14. Effective atomic number of human enamel and dentin within a photo energy range from 10 to 200 KeV

    International Nuclear Information System (INIS)

    The Z and μ/p were determined regarding the total and partial photon interactions within the biological materials of human enamel and dentin, within the low photon energy range from 10 to 200 keV, which is of medical interest in terms of radiology. The mass attenuation coefficients were calculated by means of WinXCOM. The Z for total and partial photon interactions in the biological materials of human enamel and dentin have been determined within a radiological low photon energy range from 10 to 200 keV. The total Z values presented a similar behavior in both the enamel and dentin. The Z values decreased 23% in the enamel and by 32% in the dentin in direct proportion to the increase energy levels. The Z for all partial processes increased slightly and in direct proportion to the increase in energy levels. The value for photoelectric interaction proved to be the highest, whereas the value for incoherent scattering was the lowest. The total Z becomes a contribution due these three partial processes at any energy level. The value of the Z is quite sensitive to the weight fractions of the elements and the applied interpolation method. Concerning the importance of Z values to medical dosimetry, it is expected that the new data regarding Z values presented here in will be useful, particularly as regards the energy range of interest. (author)

  15. The average 0.5-200 keV spectrum of local active galactic nuclei and a new determination of the 2-10 keV luminosity function at z \\approx 0

    CERN Document Server

    Ballantyne, D R

    2013-01-01

    The broadband X-ray spectra of AGNs contains information about the nuclear environment from Schwarzschild radii scales to distances of ~1 pc. In addition, the average shape of the X-ray spectrum is an important input into X-ray background synthesis models. Here, local (z \\approx 0) AGN luminosity functions (LFs) in five energy bands are used as a low-resolution, luminosity-dependent X-ray spectrometer in order to constrain the average AGN X-ray spectrum between 0.5 and 200 keV. The 15-55 keV LF measured by Swift-BAT is assumed to be the best determination of the local LF, and then a spectral model is varied to determine the best fit to the 0.5-2 keV, 2-10 keV, 3-20 keV and 14-195 keV LFs. The spectral model consists of a Gaussian distribution of power-laws with a mean photon-index and cutoff energy E_cut, as well as contributions from distant and disc reflection. The reflection strength is parameterised by varying the Fe abundance relative to solar, A_Fe, and requiring a specific Fe K equivalent width (EW). ...

  16. 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.

  17. K+ charge transfer in H2 at low keV collisions

    Science.gov (United States)

    Alarcón, F. B.; Martinez, H.; Fuentes, B. E.; Yousif, F. B.

    2013-08-01

    Absolute electron capture cross sections for the K+-H2 pair, employing beam collision spectroscopy for 0.4-4 keV energy were measured. The capture cross section increased with the increase in collision energy. The results below 2 keV overlap with previously measured data of other investigators and extend down in energy to 400 eV, where no previous data have been reported. Experimental data were compared with calculations employing the Olson model, which were found to agree in behavior as well as with an absolute value above 100 keV.

  18. 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.

  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. Absolute calibration of Kodak Biomax-MS film response to x rays in the 1.5- to 8-keV energy range

    Science.gov (United States)

    Marshall, F. J.; Knauer, J. P.; Anderson, D.; Schmitt, B. L.

    2006-10-01

    The absolute response of Kodak Biomax-MS film to x rays in the range from 1.5- to 8-keV has been measured using a laboratory electron-beam generated x-ray source. The measurements were taken at specific line energies by using Bragg diffraction to produce monochromatic beams of x rays. Multiple exposures were taken on Biomax MS film up to levels exceeding optical densities of 2 as measured by a microdensitometer. The absolute beam intensity for each exposure was measured with a Si (Li) detector. Additional response measurements were taken with Kodak direct exposure film (DEF) so as to compare the results of this technique to previously published calibrations. The Biomax-MS results have been fitted to a semiempirical mathematical model (Knauer et al., these proceedings). Users of the model can infer absolute fluences from observed exposure levels at either interpolated or extrapolated energies. To summarize the results: Biomax MS has comparable sensitivity to DEF film below 3keV but has reduced sensitivity above 3keV (˜50%). The lower exposure results from thinner emulsion layers, designed for use with phosphor screens. The ease with which Biomax-MS can be used in place of DEF (same format film, same developing process, and comparable sensitivity) makes it a good replacement.

  1. Construction and performance test of radiation shielding for 300 keV/20 mA electron beam machine

    International Nuclear Information System (INIS)

    The construction and performance test of radiation shielding for 300 keV/20 mA electron beam machine (EBM) has been done. Radiation shielding is used for reduce X-ray radiation which is generated by operation of the EBM, so it is not harmful for people who work in that environment. Radiation shielding plates made of bars of lead (Pb) with a length of 135 cm, 10 cm of width, 2.5 cm of thick and composed a EBM radiation shielding. The plates are made of lead by way of casting and finished mechanically by machine, then installed manually on a frame to form a EBM radiation shielding. In the calculation of thick radiation shield already qualified dose rate limit is set by BAPETEN ≤ 2.5 mrem/hr. The results of the initial test radiation shielding is functioning, it is shown by the results of measurements of the maximum dose rate 0.26 mrem/hr at the operating conditions of EBM with voltage 209 kV and 50 mA of electron beam current. Based on the results test of the construction of radiation shielding are qualified dose rate limit set by BAPETEN. (author)

  2. High Spatial Resolution STXM at 6.2 keV Photon Energy

    Science.gov (United States)

    Vila-Comamala, Joan; Dierolf, Martin; Kewish, Cameron M.; Thibault, Pierre; Pilvi, Tero; Färm, Elina; Guzenko, Vitaliy; Gorelick, Sergey; Menzel, Andreas; Bunk, Oliver; Ritala, Mikko; Pfeiffer, Franz; David, Christian

    2010-04-01

    We report on a zone-doubling technique that bypasses the electron-beam lithography limitations for the production of X-ray diffractive optics and enables the fabrication of Fresnel zone plates with smaller outermost zone widths than other well-established approaches. We have applied this method to manufacture hard X-ray Fresnel zone plates with outermost zone widths of 25 and 20 nm. These lenses have been tested in scanning transmission X-ray microscopy (STXM) at energies up to 6.2 keV, producing images of test structures that demonstrate a spatial resolution of 25 nm. High spatial resolution STXM images of several biological specimens have been acquired in transmission, dark-field and differential phase contrast modes.

  3. Measurement of D(d,p)T Reaction Cross Sections in Sm Metal in Low Energy Region (10(≤) Ed(≤)20 keV)

    Institute of Scientific and Technical Information of China (English)

    WANG Tie-Shan; YANG Zhen; H. Yunemura; A. Nakagawa; LV Hui-Yi; CHEN Jian-Yong; LIU Sheng-Jin; J. Kasagi

    2007-01-01

    To study the screening effect of nuclear reactions in metallic environments, the thick target yields, the cross sections and the experimental S(E) factors of the D{d,p)T reaction have been measured on deuterons implanted in Sm metal at 133.2 K for beam energies ranging from 10 to 20keV. The thick target yields of protons emitted in the D(d,p)T reaction are measured and compared with those data extrapolated from cross sections and stopping power data at higher energies. The screening potential in Sm metal at 133.2K is deduced to be 520±56eV. As compared with the value achieved in the gas target, the calculated screening potential values are much larger. This screening potential cannot be simply interpreted only by the electron screening. Energy dependences of the cross section cr(E) and the experimental S(E) factor for D(d,p)T reaction in Sm metal at 133.2K are obtained, respectively.

  4. Attenuation coefficients of soils and some building materials of Bangladesh in the energy range 276-1332 keV.

    Science.gov (United States)

    Alam, M N; Miah, M M; Chowdhury, M I; Kamal, M; Ghose, S; Rahman, R

    2001-06-01

    The linear and mass attenuation coefficients of different types of soil, sand, building materials and heavy beach mineral samples from the Chittagong and Cox's Bazar area of Bangladesh were measured using a high-resolution HPGe detector and the gamma-ray energies 276.1, 302.8, 356.0, 383.8, 661.6 and 1173.2 and 1332.5 keV emitted from point sources of 133Ba, 137Cs and 60Co, respectively. The linear attenuation coefficients show a linear relationship with the corresponding densities of the samples studied. The variations of the mass attenuation coefficient with gamma-ray energy were exponential in nature. The measured mass attenuation coefficient values were compared with measurements made in other countries for similar kinds of materials. The values are in good agreement with each other in most cases. PMID:11300413

  5. 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

  6. High-accuracy determination of the relative full energy peak efficiency curve of a coaxial HPGe detector in the energy range 700-1300 keV

    International Nuclear Information System (INIS)

    A method for the high-accuracy determination of the relative full energy peak efficiency is established. Radionuclides that emit at least two gamma-ray lines for which the relative intensity can be found (from the decay scheme) to much better than ±0.1% were used as calibration standards. Specifically, the 889 and 1120 keV lines of 46Sc, the 983 and 1312 keV lines of 48Sc, the 1173 and 1332 keV lines of 60Co, and the 702 and 871 keV lines of 94Nb were implemented. The high-accuracy calibration was taken to extend from the lowest line of 94Nb at 702 keV to the highest line of 60Co at 1332 keV. An analytical expression, based on linear least-squares fitting, was developed to describe the behavior of the relative efficiency curve in that energy range. As a result, the ability of predicting relative full energy peak efficiencies to within ±0.1% (over most of the energy range) was demonstrated. The presented method is applicable in any measurement that requires the minimum calibration bias in the determination of reaction rate ratios. Applications in neutron activation analysis (NAA) and in nuclear reactor dosimetry represent examples of such situations. (orig.)

  7. 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.

  8. 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.

  9. 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.

  10. 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...

  11. 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.

  12. Energy dependence of some neutron detector sensitivity in the energy range from 17 keV up to 1 MeV

    International Nuclear Information System (INIS)

    The results of experimental determination of sensitivity of neutron detectors used as dosimeters in the energy range from 17 keV to 1 MeV are presented. The measurements were performed in the EhG-2.5 accelerator. Monoenergetic neutrons were produced in the T (p, n)3He reaction at different proton energies. The detectors were placed at angles from 30 deg to 120 deg to proton beam direction. The detector sensitivity was evaluated by comparison of their values with those of the OVC-3M standard neutron counter. The obtained results could be used for determining energy dependences of sensitivities of detectors under study and for evaluating the errors of measurements of neutron doses in the radiation fields behind nuclear-physical installation shielding

  13. The High Energy Emission of the Crab Nebula from 20 keV to 6 MeV with INTEGRAL

    CERN Document Server

    Jourdain, E

    2009-01-01

    The SPI spectrometer aboard the INTEGRAL mission observes regularly the Crab Nebula since 2003. We report on observations distributed over 5.5 years and investigate the variability of the intensity and spectral shape of this remarkable source in the hard X-rays domain up to a few MeV. While single power law models give a good description in the X-ray domain (mean photon index ~ 2.05) and MeV domain (photon index ~ 2.23), crucial information are contained in the evolution of the slope with energy between these two values. This study has been carried out trough individual observations and long duration (~ 400 ks) averaged spectra. The stability of the emission is remarkable and excludes a single power law model. The slopes measured below and above 100 keV agree perfectly with the last values reported in the X-ray and MeV regions respectively, but without indication of a localized break point. This suggests a gradual softening in the emission around 100 keV and thus a continuous evolution rather than an actual c...

  14. 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...

  15. Conceptual design of negative-ion-based 500 keV, 20 MW neutral beam injector

    International Nuclear Information System (INIS)

    The conceptual design of the source plasma generator and the accelerating system is presented. Three candidate systems are then examined, each with a different neutralizing cell. The system having a very long neutralizer was judged to be the most suitable to the reactor considered. It was designed in detail. The long neutralizer (30 m) has many advantages: (1) the ion source can be located far from the reactor, permitting a narrow injection tube and tangential injection angle; (2) neutron shielding is easy because the solid angle of the beam line is very small; (3) complex components are removed from the vicinity of the reactor

  16. The average 0.5-200 keV spectrum of local active galactic nuclei and a new determination of the 2-10 keV luminosity function at z ≈ 0

    Science.gov (United States)

    Ballantyne, D. R.

    2014-01-01

    The broad-band X-ray spectra of active galactic nuclei (AGNs) contains information about the nuclear environment from Schwarzschild radii scales (where the primary power law is generated in a corona) to distances of ˜1 pc (where the distant reflector may be located). In addition, the average shape of the X-ray spectrum is an important input into X-ray background synthesis models. Here, local (z ≈ 0) AGN luminosity functions (LFs) in five energy bands are used as a low-resolution, luminosity-dependent X-ray spectrometer in order to constrain the average AGN X-ray spectrum between 0.5 and 200 keV. The 15-55 keV LF measured by Swift-BAT is assumed to be the best determination of the local LF, and then a spectral model is varied to determine the best fit to the 0.5-2 keV, 2-10 keV, 3-20 keV and 14-195 keV LFs. The spectral model consists of a Gaussian distribution of power laws with a mean photon-index and cutoff energy Ecut, as well as contributions from distant and disc reflection. The reflection strength is parametrized by varying the Fe abundance relative to solar, AFe, and requiring a specific Fe Kα equivalent width (EW). In this way, the presence of the X-ray Baldwin effect can be tested. The spectral model that best fits the four LFs has = 1.85 ± 0.15, E_{cut}=270^{+170}_{-80} keV, A_{Fe}=0.3^{+0.3}_{-0.15}. The sub-solar AFe is unlikely to be a true measure of the gas-phase metallicity, but indicates the presence of strong reflection given the assumed Fe Kα EW. Indeed, parametrizing the reflection strength with the R parameter gives R=1.7^{+1.7}_{-0.85}. There is moderate evidence for no X-ray Baldwin effect. Accretion disc reflection is included in the best-fitting model, but it is relatively weak (broad iron Kα EW BAT and RXTE. We therefore present a new determination of the local 2-10 keV LF that is consistent with all other energy bands, as well as the de-evolved 2-10 keV LF estimated from the XMM-Newton Hard Bright Survey. This new LF should be used

  17. Absolute Doubly Differential Cross Sections for Ejection of Electrons in - and Five-Body Collisions of 20 TO 114-KEV Protons on Atomic and Molecular Hydrogen.

    Science.gov (United States)

    Kerby, George W., III

    A crossed-beam experiment was performed to detect ejected electrons from ground-state atomic and molecular hydrogen after collisions with 20- to 114-keV protons. Because a pure atomic hydrogen target is not readily attainable, a method has been devised which yields atomic to molecular hydrogen doubly differential cross section (DDCS) ratios. Since the molecular hydrogen DDCS's were independently measured, the atomic cross sections could be directly calculated. Absolute cross sections differential in electron energy and angle were measured for electron energies ranging from 1.5 to 400 eV and scattering angles from 15^circ to 165^circ with respect to the fast beam. Electrons and ions were energy analyzed by an electrostatic hemispherical analyzer, which has an energy resolution of 5% and is rotatable in the scattering plane about the collision center. Atomic hydrogen is produced by a radio-frequency discharge of the type devised by J. Slevin. Hydrogen gas effuses from a 1 mm diameter nozzle in a nearly cos theta distribution. The projectile beam intersects the thermal gas targets 4 mm below the tip of the nozzle. Dissociation fractions of 74% and atomic hydrogen densities of 7 times 10 ^{11} cm^ {-3} were typical. The fraction of dissociated hydrogen was measured by detecting the reduced 9-eV ion signal from the molecular target when the RF is on. This characteristic ion signal originates from the coulomb breakup of the molecule and dissociative channels of excited H _sp{2}{+}. An auxiliary experiment was performed to determine the target densities with the aid of a low-resolution magnetic mass spectrometer after the slow recoil ions were extracted from the collision volume by a weak electric field. Comparisons of the atomic cross sections are made with theories such as the classical-trajectory Monte Carlo (CTMC) method, the plane-wave Born approximation (PWBA) and the continuum-distorted-wave eikonal-initial-state (CDW-EIS) approximation.

  18. 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.

  19. Studies on the attenuation coefficients of some egyptian materials In the energy range 81-1332.5 KeV

    International Nuclear Information System (INIS)

    The linear and mass attenuation coefficients for different types of soil, sand and some building material samples at Inshas site in Egypt were investigated. The measurements were performed using gamma rays spectrometer consists of hyper pure germanium (HPGe) detector. The attenuation coefficients values were determined at the y-rays energies 81.0, 276.4, 302.8, 356.0 and 383.9 KeV of l33Ba, 661.7 KeV of 137Cs and 1173.4 and 1332.5 KeV of 60Co. The tested samples were dried, sieved to different particle sizes. The effect of cement to sand ratio on the attenuation coefficient values was studied. The results obtained showed that there was no specific relation between the mass attenuation coefficients and samples densities, but there was exponential decay relation between the mass attenuation coefficients and the gamma rays energy. There were variations of the values of the mass attenuation coefficients with the γ-rays energy. The obtained values for mass attenuation coefficients were compared with other values in different countries. These values agreed with some values and differed with others, because there are differences in the elemental components of each sample

  20. Electron-transfer reactions of fast Xe/sup n/+ ions with Xe in the energy range 15 keV to 1.6 MeV

    International Nuclear Information System (INIS)

    Electron-transfer cross sections for the reactions of Xe/sup n/+ (n = 1--4) with Xe atoms have been determined as a function of projectile-ion kinetic energy in the range 15 keV--1.6 MeV. For Xe/sup n/+ (n = 2, 3, 4), cross sections for sequential transfer of two or more electrons in single-ion--atom collisions have been obtained. These cross sections decrease with increasing number of electrons transferred. The observed insensitivity of cross sections to projectile kinetic energy in the range investigated follows the condition that the linear velocity of the ion is less than the orbital velocity of a valence electron in the slow-moving target atom. Attenuation cross sections for reactions of Xe/sup n/+ (n = 2, 3, 4) follow approximately a Z2/sub direct-sum/ charge dependence. A simple classical model based on Coulomb forces yields cross sections with a reasonable fit to the experimental data

  1. Polarization evidence for the isotropy of electrons responsible for the production of 5-20 keV X-rays in solar flares

    Science.gov (United States)

    Tramiel, L. J.; Novick, R.; Chanan, G. A.

    1984-05-01

    We have flown a solar flare X-ray polarimeter on the third flight (STS 3) of the Space Shuttle Columbia as part of the OSS-1 pallet of instruments. We observed eight solar flares in the 5-20 keV band on 1982 March 28. The signal-to-background ratio in all cases exceeded 25. A preflight contamination problem invalidated the earlier laboratory calibration, and the instrument had to be calibrated in-flight against two flares near the center of the solar disk, which are expected to be unpolarized on geometric grounds in a variety of models. No statistically significant polarization was then detected in any of the other six flares. Upper limits (99% confidence level) range from 2.5% to 12.7%. For two of the observed flares these results disagree with the predictions of a simple radially beamed, linear bremsstrahlung model at greater than 99% confidence. One of these flares had a hard impulsive burst; the measured upper limit on this burst (10%) also disagrees with the predictions of the beamed hypothesis. If the calibration flares were polarized, then the above upper limits can be interpreted as limits on the changes in polarization from flare to flare. Because the observed flares spanned a large longitude range and because the predictions of the beamed models depend fairly sensitively on viewing angle, the small relative polarizations are still difficult to reconcile with simple beamed models. The results are also compared with recent, more sophisticated models of Leach and Petrosian, which generally predict lower polarizations. We find that the observations are marginally inconsistent with a model in which the electrons are initially strongly beamed, but subsequently become largely isotropic as a result of the effects of a converging magnetic field; they are consistent with a model in which the electrons are injected isotropically, but in which the preference for motion along the magnetic field lines is explicitly taken into account. The results are also consistent

  2. Dissociative ionization cross sections of CO2 at electron impact energy of 5 keV

    International Nuclear Information System (INIS)

    The dissociative ionization of CO2 induced by 5 keV electrons in two-body and three-body dissociative channels of CO22+ and CO23+ is identified by the ion—ion coincidence- method using a momentum imaging spectrometer. The partial ionization cross sections (PICSs) of different ionic fragments are measured and the results generally agree with the calculations made by a semi-empirical approach. Furthermore, the PICSs of the dissociative channels are also obtained by carefully considering the detection efficiency of the micro-channel plates and the total transmission efficiency of the time of flight system. (atomic and molecular physics)

  3. INTEGRAL observations of the cosmic X-ray background in the 5-100 keV range via occultation by the Earth

    DEFF Research Database (Denmark)

    Churazov, E.; Sunyaev, R.; Revnivtsev, M.;

    2007-01-01

    Aims. We study the spectrum of the cosmic X-ray background (CXB) in energy range similar to 5-100 keV. Methods. Early in 2006 the INTEGRAL observatory performed a series of four 30 ks observations with the Earth disk crossing the field of view of the instruments. The modulation of the aperture flux...... due to occultation of extragalactic objects by the Earth disk was used to obtain the spectrum of the Cosmic X-ray Background ( CXB). Various sources of contamination were evaluated, including compact sources, Galactic Ridge emission, CXB reflection by the Earth atmosphere, cosmic ray induced emission...... by the Earth atmosphere and the Earth auroral emission. Results. The spectrum of the cosmic X-ray background in the energy band 5-100 keV is obtained. The shape of the spectrum is consistent with that obtained previously by the HEAO-1 observatory, while the normalization is similar to 10% higher...

  4. The Fano factor in gaseous xenon: A Monte Carlo calculation for X-rays in the 0.1 to 25 keV energy range

    International Nuclear Information System (INIS)

    A calculation of the Fano factor for gaseous xenon is carried out using a detailed Monte Carlo simulation of the absorption of X-rays in the 0.1 to 25 keV energy range. This factor is found to be energy dependent with values ranging from 0.17 to 0.32 and has sharp increases near the xenon absorption edges. An interpretation of the calculated results is made in terms of the relative importance of photoelectron and Auger/Coster-Kronig cascading electron processes. (orig.)

  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. Optical excitation function of H(1s-2p) produced by electron impact from threshold to 1.8 keV

    International Nuclear Information System (INIS)

    The optical excitation function of prompt Lyman-α 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 monochromator system was used to measure the emitted Lyman-α 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. Our data are significantly different from the earlier experimental results and which are limited to energies below 200 eV. 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 endash 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 endash 1.8 keV energy range. (Abstract Truncated)

  7. 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.

  8. 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.

  9. 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)

  10. A novel flat-response x-ray detector in the photon energy range of 0.1-4 keV

    International Nuclear Information System (INIS)

    A novel flat-response x-ray detector has been developed for the measurement of radiation flux from a hohlraum. In order to obtain a flat response in the photon energy range of 0.1-4 keV, it is found that both the cathode and the filter of the detector can be made of gold. A further improvement on the compound filter can then largely relax the requirement of the calibration x-ray beam. The calibration of the detector, which is carried out on Beijing Synchrotron Radiation Facility at Institute of High Energy Physics, shows that the detector has a desired flat response in the photon energy range of 0.1-4 keV, with a response flatness smaller than 13%. The detector has been successfully applied in the hohlraum experiment on Shenguang-III prototype laser facility. The radiation temperatures inferred from the detector agree well with those from the diagnostic instrument Dante installed at the same azimuth angle from the hohlraum axis, demonstrating the feasibility of the detector.

  11. 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.

  12. 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...

  13. SURVIVAL DEPTH OF ORGANICS IN ICES UNDER LOW-ENERGY ELECTRON RADIATION (≤2 keV)

    International Nuclear Information System (INIS)

    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–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 could

  14. 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.

  15. 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...

  16. 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.

  17. 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).

  18. Electron stopping power and inelastic mean free path in amino acids and protein over the energy range of 20-20,000 eV.

    Science.gov (United States)

    Tan, Zhenyu; Xia, Yueyuan; Zhao, Mingwen; Liu, Xiangdong

    2006-07-01

    Systematic calculations of stopping power (SPs) and inelastic mean free path (IMFP) values for 20-20,000 eV electrons in a group of 15 amino acids and a simple protein have been performed. The calculations are based on the dielectric response model and take into account the exchange effect between the incident electron and target electrons. The optical energy-loss functions for the 15 investigated amino acids and the protein are evaluated by using an empirical approach, because of the lack of experimental optical data. For all the considered materials, the calculated mean ionization potentials are in good agreement with those given by Bragg's rule, and the evaluated SP values at 20 keV converge well to the Bethe-Bloch predictions. The data shown represent the first results of SP and IMFP, for these 15 amino acids and the protein in the energy range below 20 keV, and might be useful for studies of various radiation effects in these materials. In addition, the average energy deposited by inelastic scattering of the electrons on this group of 15 amino acids, on the protein, on Formvar and on DNA, respectively, has been estimated for energies below 20 keV. The dependences of the average energy deposition on the electron energy are given. These results are important for any detailed studies of radiation-induced inactivation of proteins and the DNA. PMID:16733724

  19. 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.

  20. Optical excitation function of H(1s-2p) produced by electron impact from threshold to 1.8 keV

    Energy Technology Data Exchange (ETDEWEB)

    James, G.K. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States); Slevin, J.A. [Department of Experimental Physics, St. Patricks College, Maynooth, County Kildare (Ireland); Shemansky, D.E. [Department of Aerospace Engineering, University of Southern California, Los Angeles, California 90089 (United States); McConkey, J.W. [Department of Physics, University of Windsor, Windsor, Ontario, N9B3P4 (CANADA); Bray, I. [Electronic Structure of Materials Centre, The Flinders University of South Australia, G.P.O. Box 2100, Adelaide 5001 (Australia); Dziczek, D. [Institute of Physics, Nicholas Copernicus University, 87-100 Torun (Poland); Kanik, I.; Ajello, J.M. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

    1997-02-01

    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 monochromator 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. Our data are significantly different from the earlier experimental results and which are limited to energies below 200 eV. Statistical and known systematic uncertainties in our data range from {plus_minus}4{percent} near threshold to {plus_minus}2{percent} 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{percent} level in the analysis of the experimental data. The derived optimized absolute cross sections are within 7{percent} of the CCC calculations over the 14 eV{endash}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{percent} 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 {endash} 1.8 keV energy range. (Abstract Truncated)

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

    Science.gov (United States)

    Mohd Yusof, Mohd Fahmi; Hamid, Puteri Nor Khatijah Abdul; Bauk, Sabar; Hashim, Rokiah; Tajuddin, Abdul Aziz

    2015-04-01

    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).

  2. High accuracy experimental determination of copper and zinc mass attenuation coefficients in the 100 eV to 30 keV photon energy range

    Science.gov (United States)

    Ménesguen, Y.; Gerlach, M.; Pollakowski, B.; Unterumsberger, R.; Haschke, M.; Beckhoff, B.; Lépy, M.-C.

    2016-02-01

    The knowledge of atomic fundamental parameters such as mass attenuation coefficients with low uncertainties, is of decisive importance in elemental quantification using x-ray fluorescence analysis techniques. Several databases are accessible and frequently used within a large community of users. These compilations are most often in good agreement for photon energies in the hard x-ray ranges. However, they significantly differ for low photon energies and around the absorption edges of any element. In a joint cooperation of the metrology institutes of France and Germany, mass attenuation coefficients of copper and zinc were determined experimentally in the photon energy range from 100 eV to 30 keV by independent approaches using monochromatized synchrotron radiation at SOLEIL (France) and BESSY II (Germany), respectively. The application of high-accuracy experimental techniques resulted in mass attenuation coefficient datasets determined with low uncertainties that are directly compared to existing databases. The novel datasets are expected to enhance the reliability of mass attenuation coefficients.

  3. 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...

  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. 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)

  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. 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...

  8. 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...

  9. Time-resolved analysis of the X-ray emission of femtosecond-laser-produced plasmas in the 1.5-keV range

    Science.gov (United States)

    Bastiani-Ceccotti, S.; Audebert, P.; Nagels-Silvert, V.; Geindre, J. P.; Gauthier, J. C.; Adam, J. C.; Héron, A.; Chenais-Popovics, C.

    Recent experimental results on ion beams produced in high-intensity laser-solid interactions indicate the presence of very intense electric fields in the target. This suggests the possibility of efficiently heating a solid material by means of the fast electrons created during the laser-solid interactions and trapped in the target, rather than by the laser photons themselves. We tested this mechanism by irradiating very small cubic aluminum targets with the LULI 100-TW, 300-fs laser at 1.06-μm wavelength. X-ray spectra were measured with an ultra-fast streak camera, coupled to a conical Bragg crystal, providing spectra in the 1.5-keV range with high temporal and spectral resolution. The results indicate the creation of a hot plasma, but a very low coupling between the rapid electrons and the solid. A tentative explanation, in agreement with other experimental results and with preliminary particle-in-cell (PIC) simulations, points out the fatal role of the laser prepulse.

  10. Development of a flat-field spectrograph with a wide-band multilayer grating and prefocusing mirror covering 2-4 keV

    International Nuclear Information System (INIS)

    A flat-field spectrograph equipped with a wide-band multilayer grating and prefocusing mirror covering 2–4 keV without any mechanical movement has been developed. To realize this, a new multilayer structure consisting of W and B4C layers has been invented, which enhances the diffraction efficiency of the grating over the whole energy range at a fixed angle of incidence as well as the reflectivity of the prefocusing mirror. The multilayer has been deposited on a laminar-type varied-line-spacing holographic replica grating and a spherical mirror substrate. The diffraction efficiency of the multilayer grating varies between 1.2% and 3.3% at 88.65° in the 2.1–4.0 keV range. Also the reflectivity of the prefocusing mirror varies between 2.7% and 12% at 88.00° in the same range. The overall throughput of the spectrograph with the multilayer optics is 104 times higher than that of gold-coated optics.

  11. Preliminary Milling Tests on STAVAX ESR 52 HRC using 2 mm carbide tools in the range 20 – 200 m/min

    DEFF Research Database (Denmark)

    Bissacco, Giuliano

    . This consciousness has opened a new field of investigation in material removal machining operations. This new machining concept can be applied with good results to the manufacturing of dies and molds. In fact, reduced manufacturing lead times and costs can be achieved by machining directly in pre-hardened materials...... in order to test the actual potentials of the present manufacturing solutions, the high speed cutting range can’t always be reached, since it depends not only on the maximum spindle speed of the available machine, but, when dealing with milling, also on the tool diameter. This is obviously a limitation...

  12. Spectroscopic monitoring of gamma-rays of Earth and space origin in the 150-6400 KeV range at Moussala BEO

    International Nuclear Information System (INIS)

    A gamma-spectrometer with a NaI detector and a suitable lead collimator directed to the sky was put in operation at Moussala BEO at an altitude of 2925 m above sea level. The gamma-rays spectrum in the 150–6500 keV energy interval was measured at two-hour intervals. In many cases, significant fluctuations were observed in the 222Rn lines intensity. Fluctuations of the gamma-rays intensity in the 2800–6400 keV energy interval were also observed. These gamma-rays originate from the interaction of various cosmic rays with Earth’s atmosphere. The device’s stability was controlled through the intensity of the 1460 keV gamma-line of the 40K background. Key words: Moussala, gamma-rays, NaI, detector, fluctuations, atmosphere

  13. 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

  14. Revisiting the relationship between 6 {\\mu}m and 2-10 keV continuum luminosities of AGN

    OpenAIRE

    Mateos, S; Carrera, F. J.; Alonso-Herrero, A.; Rovilos, E.; Hernán-Caballero, A.; Barcons, X.; Blain, A.; Caccianiga, A.; R. Della Ceca(INAF, Oss. di Brera); Severgnini, P.

    2015-01-01

    We have determined the relation between the AGN luminosities at rest-frame 6 {\\mu}m associated to the dusty torus emission and at 2-10 keV energies using a complete, X-ray flux limited sample of 232 AGN drawn from the Bright Ultra-hard XMM-Newton Survey. The objects have intrinsic X-ray luminosities between 10^42 and 10^46 erg/s and redshifts from 0.05 to 2.8. The rest-frame 6 {\\mu}m luminosities were computed using data from the Wide-Field Infrared Survey Explorer and are based on a spectral...

  15. Bolometer characterisation with a specially developed cryogenic source having more than five peaks in the 1-6 keV range

    International Nuclear Information System (INIS)

    A very low temperature (10-50 mK), and at relatively low energy (typically 100 eV-10 keV), the linearity and resolution of bolometers need to be carefully tested. Commercially available sources below 6 keV are rate and difficult to cool down. We have developed a specially designed compact X-ray source where 55Fe is combined with an ion-exchange membrane containing more than three fluorescent elements. More than five peaks can be identified form 1 keV to 6.5 keV. A spectrum obtained with a 0.5 mg composite diamond bolometer, allowing a good measurement of linearity and resolution as a function of energy is presented. It is compared with a spectrum of the same source measured with a classical germanium detector. Since bolometer detectors have neither window, nor dead layer effects. Bolometer spectra obtained with these sources could be used to directly calibrate the efficiency response of classical detectors at very low energy. (orig.)

  16. Revisiting the relationship between 6 {\\mu}m and 2-10 keV continuum luminosities of AGN

    CERN Document Server

    Mateos, S; Alonso-Herrero, A; Rovilos, E; Hernán-Caballero, A; Barcons, X; Blain, A; Caccianiga, A; Della Ceca, R; Severgnini, P

    2015-01-01

    We have determined the relation between the AGN luminosities at rest-frame 6 {\\mu}m associated to the dusty torus emission and at 2-10 keV energies using a complete, X-ray flux limited sample of 232 AGN drawn from the Bright Ultra-hard XMM-Newton Survey. The objects have X-ray luminosities corrected for intrinsic absorption between 10^42 and 10^46 erg/s and redshifts from 0.05 to 2.8. The rest-frame 6 {\\mu}m luminosities were computed using data from the Wide-Field Infrared Survey Explorer and are based on a spectral energy distribution decomposition into AGN and galaxy emission. The best-fit relationship for the full sample is consistent with being linear, L_6 {\\mu}m $\\propto$ L_2-10 keV^0.99$\\pm$0.032, but has significant intrinsic scatter, ~0.35 dex in log L_6 {\\mu}m. Assuming a constant X-ray bolometric correction, the fraction of AGN bolometric luminosity reprocessed in the mid-IR decreases weakly, if at all, with the AGN luminosity, a finding at odds with simple receding torus models. Type 2 AGN have re...

  17. 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

  18. 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...

  19. Radiation damage induced by 5 keV Si + ion implantation in strained-Si/Si 0.8Ge 0.2

    Science.gov (United States)

    Matsushita, T.; Sakai, W.; Nakajima, K.; Suzuki, M.; Kimura, K.; Agarwal, A.; Gossmann, H.-J.; Ameen, M.

    2005-04-01

    The damage distributions induced by ultra low energy ion implantation (5 keV Si+) in both strained-Si/Si0.8Ge0.2 and normal Si are measured using high-resolution RBS/channeling with a depth resolution better than 1 nm. Ion implantation was performed at room temperature over the fluence range from 2 × 1013 to 1 × 1015 ions/cm2. Our HRBS results show that the radiation damage induced in the strained Si is slightly larger than that in the normal Si at fluences from 1 × 1014 to 4 × 1014 ions/cm2 while the amorphous width is almost the same in both strained and normal Si.

  20. 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).

  1. Linear and mass attenuation coefficient for CdTe compound of X-rays from 10 to 100 keV energy range in different phases

    International Nuclear Information System (INIS)

    The Full Potential Linear Muffin Tin Orbitals method within the density functional theory has been utilized to calculate structural and electronic properties of the CdTe compound. We have checked that the CdTe has two phase-transitions from zinc-blend to cinnabar and from cinnabar to rocksalt. We have found that the rigidity, the energy and the nature of the gap change according to the phase change, so we can predict that a CdTe detector may have different behaviors in different phase conditions. In order to investigate this behavior change, the linear and the mass attenuation coefficients of X-ray in rocksalt, zinc-blend and cinnabar structures are calculated from 10 keV to100 keV, using the XCOM data. We have found that when CdTe undergoes a phase transition from zinc-blend to cinnabar, its linear attenuation coefficient decreases down to a value of about 100 times smaller than its initial one, and when it undergoes a transition from cinnabar to rocksalt it increases up to a value about 90 times larger than its initial one

  2. 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 ...

  3. Studies on effective atomic numbers and electron densities in amino acids and sugars in the energy range 30-1333 keV

    Energy Technology Data Exchange (ETDEWEB)

    Gowda, Shivalinge [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006 (India); Krishnaveni, S. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006 (India); Gowda, Ramakrishna [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006 (India)]. E-mail: ramakrishnagowda@yahoo.com

    2005-10-15

    The effective atomic numbers and electron densities of the amino acids glycine, alanine, serine, valine, threonine, leucine, isoleucine, aspartic acid, lysine, glutamic acid, histidine, phenylalanine, arginine, tyrosine, tryptophane and the sugars arabinose, ribose, glucose, galactose, mannose, fructose, rhamnose, maltose, melibiose, melezitose and raffinose at the energies 30.8, 35.0, 81.0, 145, 276.4, 302.9, 356, 383.9, 661.6, 1173 and 1332.5 keV were calculated by using the measured total attenuation cross-sections. The interpolations of total attenuation cross-sections for photons of energy E in elements of atomic number Z was performed using the logarithmic regression analysis of the XCOM data in the photon energy region 30-1500 keV. The best-fit coefficients obtained by a piece wise interpolation method were used to find the effective atomic number and electron density of the compounds. These values are found to be in good agreement with the theoretical values calculated based on XCOM data.

  4. 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

  5. Guiding of 60 keV O6+ Ions through Nanocapillaries in an Uncoated Al2O3 Membrane

    Institute of Scientific and Technical Information of China (English)

    CHEN Xi-Meng; YIN Yong-Zhi; LOU Feng-Jun; WANG Xing-An; XU Jun-Kui; ZHOU Chun-Lin; XI Fa-Yuan; QIU Xi-Yu; SHAO Jian-Xiong; CUI Ying; SUN Guang-Zhi; WANG Jun; CHEN Yi-Feng; LIU Hui-Ping

    2008-01-01

    @@ We measure the transmission of O6+ ions with a higher energy of 6O keV (in turna higher value of Ep/q) through capillaries in an uncoated Al2O3 membrane, and obtain agreements with previously reported results in general angular distribution of the transmitted ions and the transmission profile width variation with capillary tilt angle.The transmission fractions as a function of the tilt angle can be fitted to the semi-empirical Gaussian-like function well. Due to using uncoated capillary membrane, our ψc is larger than that using gold-coated one, in spite of our larger value of Ep/q, which suggests a larger equilibrium charge Q∞ in our experiment.

  6. Electron Flux Models at GEO: 30 keV - 600 keV

    Science.gov (United States)

    Boynton, R.; Balikhin, M. A.; Sibeck, D. G.; Walker, S. N.; Ganushkina, N. Y.

    2015-12-01

    Forecast models are developed for the electron fluxes measured by the Magnetospheric Electron Detector (MagED) onboard the Geostationary Operational Environmental Satellite (GOES) 13. The models employ solar wind and geomagnetic indices as inputs to produce a forecast of the electron flux at Geostationary Earth Orbit (GEO) for five energy ranges from 30 keV - 600 keV. All of these models will be implemented in real time to forecast the electron fluxes on the PROGRESS project website (https://ssg.group.shef.ac.uk/progress2/html/index.phtml).

  7. Calculations of electron stopping powers for 41 elemental solids over the 50 eV to 30 keV range with the full Penn algorithm

    International Nuclear Information System (INIS)

    We present mass collision electron stopping powers (SPs) for 41 elemental solids (Li, Be, graphite, diamond, glassy C, Na, Mg, Al, Si, K, Sc, Ti, V, Cr, Fe, Co, Ni, Cu, Ge, Y, Nb, Mo, Ru, Rh, Pd, Ag, In, Sn, Cs, Gd, Tb, Dy, Hf, Ta, W, Re, Os, Ir, Pt, Au, and Bi) that were calculated from experimental energy-loss-function data with the full Penn algorithm for electron energies between 50 eV and 30 keV. Improved sets of energy-loss functions were used for 19 solids. Comparisons were made of these SPs with SPs calculated with the single-pole approximation, previous SP calculations, and experimental SPs. Generally satisfactory agreement was found with SPs from the single-pole approximation for energies above 100 eV, with other calculated SPs, and with measured SPs.

  8. 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.)

  9. A Typology for Web 2.0

    DEFF Research Database (Denmark)

    Dalsgaard, Christian; Sorensen, Elsebeth Korsgaard

    2008-01-01

    of a learning environment: 1) organizing communicative processes and 2) organizing resources. Organizing communicative processes is supported by Web 2.0’s ability to provide a range of communicative tools that can be organized flexibly by students. Web 2.0 provides opportunities for communities and groups...... to organize their own communicative processes. Further, Web 2.0 supports organization of resources by empowering students to create, construct, manage and share content themselves. However, the main potential lies within collaborative creation and sharing in networks. Potentially, networking tools...

  10. Angular and velocity distributions of the HD sup + and D sub 2 sup + fragments from HD sub 2 sup + colliding with He at energies of 1 to 5 keV

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, I.; Martriaanez, H.; Cisneros, C.; de Urquijo, J. (Instituto de Fisica, Universidad Nacional Autonoma de Mexico, P.O. Box 139-B, 62191 Cuernavaca Morelos (Mexico))

    1992-01-01

    The angular and velocity distributions of the HD{sup +} and D{sub 2}{sup +} fragments resulting from collision-induced dissociation of the HD{sub 2}{sup +} molecular ion incident on He have been measured in the energy range 1--5 keV. These distributions were used to determine the binding energy of HD{sub 2}{sup +}, some of the main transitions involved in the dissociation process, and the total cross sections for the production of both fragments.

  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. Development of an X-ray imaging system within 10-30 keV spectral range based on organic or inorganic scintillator

    International Nuclear Information System (INIS)

    This thesis aims at developing an x-ray imaging system intended for the Laser Mega Joule, within the framework of Inertial Confinement Fusion (ICF) experiments. ICF aims at yielding thermonuclear energy through laser-driven fusion of a deuterium-tritium mix. The operational function of our system is to acquire an image of the 10-30 keV x-rays emitted by the maximally compressed micro-balloon, with spatial resolution better than 10 μm. The presented system is only a part of a complete diagnostic system, which normally includes an x-ray optical subsystem. Our system conception largely takes vulnerability into account. The ignition phase of ICF yields 1016 neutrons, with energies scaling up to 14 MeV. The neutrons generate such a hard surrounding with effects scaling down from image degradation up to instrumentation destruction. The presented system consists in a scintillator which is focused on a CCD camera through a catadioptric image transport system. An innovation work has been lead on scintillators to provide an answer to specifications greatly influenced by vulnerability. Those thesis works lead to an imaging system allowing to deport the CCD camera by 4 meters from the scintillator, with 100 μm spatial resolution in the scintillator plane. Those works have paved the way to outlooks such as enhancement of organic loaded scintillators compositions and improvement of optical relay system. (author)

  13. 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...

  14. 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.

  15. VizieR Online Data Catalog: 2-10keV luminosity function of AGN (Ranalli+, 2016)

    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.

    2016-02-01

    The XMM-LSS, XMM-CDFS, and XMM-COSMOS are three surveys with complementary properties in terms of luminosity and redshift coverage. We used these three surveys to derive Bayesian estimates of the unabsorbed luminosity function (LF) of AGN in the 2-10keV band. The LF estimates are presented as a set of samples from the posterior probability distribution of the LF parameters. The LF is parameterised as a double power-law, with either the luminosity and density evolution (LADE) model, or the luminosity-dependent density evolution (LDDE) model. The double power-law is described by Eq.(10) in the paper. The LADE and LDDE models are described by Eqs.(11-14) and Eqs.(15-17), respectively. A Fortran 2008 implementation of these models can be found in file src2/lumf_funcs.f90 of the LFTools package, in the classes doublepowerlaw, ladevol, and lddevol (see the paper). (8 data files).

  16. 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.

  17. 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...

  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. 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.

  20. Non-dissociative and dissociative ionization of N2, CO, CO2, and CH4 by impact of 50-6000 keV protons and antiprotons

    International Nuclear Information System (INIS)

    Measurements of the cross section for non-dissociative single ionization and the cross sections for the creation of charged fragments have been performed for 50-6000 keV antiproton and proton impact on N2, CO, CO2, and CH4. The results support the understanding of the ionization phenomenon that has been achieved via measurements with fundamental charged particles on atoms. The present high-energy antiproton fragmentation data supply a stringent test of the validity of the published electron-impact fragmentation data which, unfortunately, most of them fail. (Author)

  1. 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 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

  2. 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)

  3. 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

  4. Determination of the molecular structure via the medium energy electrons (500 eV-1,5 KeV) Ar, N2, Co e HCl

    International Nuclear Information System (INIS)

    Elastic Differential and Total Differential Cross Sections are measured for electron collision in medium-energy range (500 eV - 1,5 KeV) with argon, nitrogen, carbon monoxide and hydrogen chloride, all in their electronic ground state. Theoretical calculation for the Elastic Differential Cross Sections by atoms were done employing Hartree-Fock-Clementy wave function, and making use of Partial Wave and WKBJ Methods. Exchange effect is included in the case of argon. Independent Atom Model, Half Molecule Model and a new model, the Ionic Model were utilized for the molecular calculations. The Ionic Model is suggested for the interaction between HCl and electrons. Inelastic Differential Cross Section were also computed, making use of the First Born Approximation and Hartree-Fock-Clementi wave function. It is also demonstrated, for the first time, that medium energy electrons (500 eV - 1,5 Kev) can be used to determine molecular structure parameters, in gas phase

  5. Quite time convection electric field properties derived from keV electron measurements at the inner edge of the plasma sheet by means of GEOS 2

    International Nuclear Information System (INIS)

    From an analysis of the local time distribution of the electron upper energy limit reached by the geostationary satellite GEOS 2 in cutting through the innermost part of the electron plasma sheet during fairly quite condition the following results have been obtained, among others: An electric field model given by E = -grad(AR4 sinphi), with the dusk singular point of the forbidden region boundary at 1500, instead of at 1800 MLT, is in quite good agreement with the observations. This means that effects due to the shielding by the hot plasma of the inner magnetosphere from the convection electric field are quite strong in situations of low disturbance level. The quiet time convection electric field strength at 2100 MLT in the geostationary orbit obtained from this analysis varies in the range 0.15 - 0.3 keV/Rsub(e). Six hours earlier or later in the satellite orbit the convection field is 4 times stronger. Also when the convection field varies, some information about its magnitude can be obtained from the keV electron measurements. (author)

  6. The dissociation of {sup 13}CH and {sup 12}CH{sub 2} molecules in He and N{sub 2} at beam energies of 80-250 keV and possible implications for radiocarbon mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Schulze-Koenig, T., E-mail: schulze@phys.ethz.c [Laboratory of Ion Beam Physics, ETH Zurich (Switzerland); Seiler, M.; Suter, M.; Wacker, L.; Synal, H.-A. [Laboratory of Ion Beam Physics, ETH Zurich (Switzerland)

    2011-01-01

    Isotopic ratios of {sup 14}C at natural levels can be efficiently measured with accelerator mass spectrometry (AMS). In compact AMS systems, {sup 13}CH and {sup 12}CH{sub 2} molecular interferences are destroyed in collisions with the stripper gas, a process which can be described by dissociation cross sections. These dissociation cross sections determine the gas areal density required for sufficient attenuation of the interfering molecular beams, and are therefore key parameters in the effort to further reduce the terminal voltage and thus the size of the AMS system. We measured the dissociation cross sections of {sup 13}CH and {sup 12}CH{sub 2} in N{sub 2} and He in the energy range of 80-250 keV. In N{sub 2}, cross sections were constant for energies above 100 keV with average values per molecule of (8.1 {+-} 0.4) x 10{sup -16} cm{sup 2} for {sup 13}CH and (9.5 {+-} 0.5) x 10{sup -16} cm{sup 2} for {sup 12}CH{sub 2}. In He, cross sections were constant over the full measured range of 80-150 keV with average values of (4.2 {+-} 0.3) x 10{sup -16} cm{sup 2} and (4.8 {+-} 0.4) x 10{sup -16} cm{sup 2}, respectively. A considerable reduction of the terminal voltage from the currently used 200 kV while using N{sub 2} for {sup 13}CH and {sup 12}CH{sub 2} molecule dissociation is not possible: the required N{sub 2} areal densities of {approx}1.4 {mu}g/cm{sup 2}, consequential angular straggling and a decreasing 1+ charge state fraction would reduce the ion beam transmission too much. This is not the case for He: sufficient molecule dissociation can be obtained with gas densities of {approx}0.4 {mu}g/cm{sup 2}, for which angular straggling is relatively small. In addition, the 1+ charge state fraction still increases at lower stripping energies. Thus, the usage of He for stripping and molecule dissociation might allow the development of even smaller {sup 14}C-AMS systems than available today.

  7. 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

  8. 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....

  9. 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.

  10. 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.

  11. A determination of the Fano factor for germanium at 77.4K from measurements of the energy resolution of a 113cm3 HPGe gamma-ray spectrometer taken over the energy range from 14 to 6129 keV

    International Nuclear Information System (INIS)

    The Fano factor for germanium cooled to 77.4 K has been determined from a semiempirical analysis of the measured energy resolution of a HPGe γ-ray spectrometer of active volume 113.2 cm3. Twenty nine γ-ray energies spanning the range from 14 to 6129 keV were used in this study. The dispersion due to incomplete charge collection was assessed experimentally by making measurements over a wide range of applied bias. Plots of the peak centroid shift and the peak width squared against the reciprocal of the voltage applied to the detector, were non-linear. Both exhibited plateaus for large applied voltages. Thus, by operating in the plateau region, the Fano factor could be extracted from the variation of the observed line width as a function of energy, while the detector was known to be functioning close to the position of perfect charge collection. The value of the Fano factor obtained in this work, averaged over the energy range 14-6129 keV, was 0.112 ± 0.001. It is recommended that more, high quality, measurements be made. (author)

  12. 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 s...

  13. 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)

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

    International Nuclear Information System (INIS)

    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)

  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. ASCA Observations of the Starburst-Driven Superwind Galaxy NGC 2146 Broad Band (0.6 - 9 keV) Spectral Properties

    CERN Document Server

    Ceca, R D; Heckman, T M; Lehnert, M D; Weaver, K A

    1998-01-01

    We report ASCA GIS and SIS observations of the nearby (D = 11.6 Mpc), nearly edge-on, starburst galaxy NGC 2146. These X-ray spectral data complement ROSAT PSPC and HRI imaging discussed by Armus et al., 1995. The broad band (0.6-9 keV) X-ray spectrum of NGC 2146 is best described by a two component model: the soft X-ray emission with a Raymond-Smith thermal plasma model having a temperature of kT $\\sim 0.8$ keV; the hard X-ray emission with a thermal plasma model having kT $\\sim 8$ keV or a power-law model having a photon index of above the Galactic value. The soft (hard) thermal component provides about 30% (70%) of the total luminosity in the 0.5 - 2.0 keV energy band, while in the 2-10 keV energy range only the hard component plays a major role. The spectral results allow us to set tighter constraints on the starburst-driven superwind model, which we show can satisfactorily account for the luminosity, mass, and energy content represented by the soft X-ray spectral component. We estimate that the mass outf...

  17. 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.

  18. 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.

  19. 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 keV. The...... to fair...

  20. 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...

  1. 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

  2. 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...

  3. 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…

  4. Indicadores 2.0 para la ciencia 2.0

    OpenAIRE

    Torres Salinas, Daniel

    2009-01-01

    Comunicación presentada en el 9º Workshop de Rebiun sobre proyectos digitales, Investigación, innovación e información: tendencias en los sistemas digitales de gestión de la producción científica, celebrado en Salamanca los días 1 y 2 de octubre de 2009.

  5. 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....

  6. 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.

  7. 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...

  8. Interaction between solid nitrogen and 1--3-keV electrons

    International Nuclear Information System (INIS)

    Experimental studies were made of the interaction between solid nitrogen and beams of 1--3-keV electrons. The projected range for the electrons was measured by means of the mirror-substrate method (gold substrate), giving the result 9.02 x 1016 E/sup 1.75/ molecules/cm2 with the energy given in keV. The escape depth for secondary electrons was studied by means of the equivalent-substrate method (carbon substrate). The results varied from 280 A at 1 keV to 400 A 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 keV. 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 for solid nitrogen and for the carbon substrate. For nitrogen, it varied from 0.17 el/el at 1 keV to 0.13 el/el at 3 keV, and for carbon it varied from 0.13 to 0.12. The observations are discussed and comparisons made with other theoretical and experimental results. The agreement ranges from good to fair

  9. Preliminary measurements of doubly differential cross sections for ejection of electrons from atomic hydrogen by 70 keV protons

    International Nuclear Information System (INIS)

    A Slevin atomic hydrogen source has been used to produce a thermal beam of H and H2 as a target for 70 keV protons. A method has been devised which yields atomic to molecular hydrogen cross section ratios. Since the electron ejection cross sections for H2 are known, the atomic hydrogen cross sections can be determined. The angular and energy ranges of the detected electrons, differential in angle and energy, are 20 degrees-160 degrees and 1.5-250 eV respectively

  10. Preliminary measurements of doubly differential cross sections for ejection of electrons from atomic hydrogen by 70 keV protons

    Energy Technology Data Exchange (ETDEWEB)

    Kerby, G.W.; Gealy, M.W.; Hsu, Y.Y.; Rudd, M.E. [Univ. of Nebraska, Lincoln, NB (United States)

    1993-05-01

    A Slevin atomic hydrogen source has been used to produce a thermal beam of H and H{sub 2} as a target for 70 keV protons. A method has been devised which yields atomic to molecular hydrogen cross section ratios. Since the electron ejection cross sections for H{sub 2} are known, the atomic hydrogen cross sections can be determined. The angular and energy ranges of the detected electrons, differential in angle and energy, are 20{degrees}-160{degrees} and 1.5-250 eV respectively.

  11. Experimental study of interactions of highly charged ions with atoms at keV energies: Progress report for period January 16, 1988--February 20, 1989

    International Nuclear Information System (INIS)

    The Cornell superconducting solenoid, cryogenic electron beam ion source CEBIS II has been rebuilt around a commercial 3 Tesla superconducting solenoid manufactured by Nicolet Instrument Corporation of Madison, WI. This solenoid has very low cryogen consumption which allows us to operate it continuously in the persistent current mode. Preliminary test with a 4.5 kV, 0.08 A electron beam show 100% transmission from cathode through the main magnetic field at 3 Tesla. The source is ready for gas and ion injection tests and experiments. An external sputter PIG ion source capable of supplying singly charged ions of elements other than noble gases has been tested, and several microampere beams of aluminum and lead ions have been produced. A Wien filter and an ion beam line with focusing optics have been designed and built and are in the process of being tested. A number of experiments utilizing our smaller, conventional solenoid EBIS, CEBIS I are in progress. These include the study of ion heating in an EBIS, a study of photon emissions from highly charged ions impinging on metal surfaces and the investigation of one and several electron capture via small angle scattering of highly charged projectiles from helium at 0.1 to 0.5 keV/amu. 2 refs., 10 figs

  12. 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.

  13. 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.

  14. The 0.1-2.5-KEV X-Ray Spectrum of the O4F-STAR Zeta-Puppis

    Science.gov (United States)

    Hillier, D. J.; Kudritzki, R. P.; Pauldrach, A. W.; Baade, D.; Cassinelli, J. P.; Puls, J.; Schmitt, J. H. M. M.

    1993-09-01

    We have obtained a high quality ROSAT PSPC spectrum of the bright O4f star ζ Pup. Allowing for the wind X-ray opacity, as computed from detailed non-LTE stellar wind models of ζ Pup, and under the assumption that the X-rays arise from shocks distributed throughout the wind, we have been able to match the observed X-ray spectrum (0.1 to 2.5keV). The best model fit is obtained when He++ recombines to He+ in the outer regions of the stellar wind, as predicted by recent detailed cool wind model calculations. With a single temperature plasma, the best model fit indicates a temperature of log Ts(K) = 6.5 to 6.6 corresponding to shock velocities of around 500 km s-1. A 2 temperature plasma yields a significantly improved fit, and indicates temperatures of log Ts(K) = 6.2 and 6.7 for the 2 components. The hotter component accounts for 55% of the intrinsic (75% of the observed) X-ray flux. Due to absorption by the stellar wind, and to a minor extent stellar occultation, less than 5% of the total emitted X-ray flux escapes the star. The models require significant X-ray emission (particularly at energies less than 0.5 keV) from large radii (r > 100R*). In models without recombination, the fits, even with a 2 temperature plasma, are unacceptable. A significant K shell absorption is predicted by these models, but is definitely not present in the observational data. The analysis suggests that the X-ray flux provides an invaluable diagnostic of the ionization of helium in the stellar wind of stars with low reddening.

  15. 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/

  16. 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.

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

    CERN Document Server

    Rodes-Roca, J J; Mart\\'\\inez-Núñez, S; Giménez-Garc\\'\\ia, A; Bernabéu, G

    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 our previous analysis of the XMM-Newton data. We study various possible origins and discuss the different physical scenarios in order to explain this feature. A likely interpretation is that the feature is associated with atomic transitions in an O/Ne neutron star atmosphere or of hydrogen and helium like Fe or Si ions formed in the stellar wind of the donor.

  18. Guiding of 150 keV O6+ ions through nanocapillaries in an uncoated Al2O3 membrane: special time dependence of the transmission profile width

    Institute of Scientific and Technical Information of China (English)

    Chen Xi-Meng; Xi Fa-Yuan; Qiu Xi-Yu; Shao Jian-Xiong; Xiao Guo-Qing; Cui Ying; Sun Guang-Zhi; Wang Jun; Chen Yi-Feng; Liu Hui-Ping; Yin Yong-Zhi; Wang Yu-Yu; Li De-Hui; Lou Feng-Jun; Wang Xing-An; Xu Jun-Kui; Zhou Chun-Lin

    2009-01-01

    This paper reports that the transmission of O6+ ions with energy of 150keV through capillaries in an uncoated Al2O3 membrane was measured, and agreements with previously reported results in general angular distribution of the transmitted ions and the transmission fractions as a function of the tilt angle well fitted to Gaussian-like functions were observed. Due to using an uncoated capillary membrane, our ψc is larger than that using a gold-coated one with a smaller value of Ep/q, which suggests a larger equilibrium charge Q∞ in our experiment. The observed special width variation with time and a larger width than that using a smaller Ep/q were qualitatively explained by using mean-field classical transport theory based on a classical-trajectory Monte Carlo simulation.

  19. 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

  20. 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.

  1. 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.

  2. Simultaneous removal of NOX and SO2 from flue gases by energizing gases with electrons having energy in the range from 5 eV to 20 eV

    International Nuclear Information System (INIS)

    These notes report the results obtained with an experimental installation able to treat 100 Nm3/h of flue gases, installed at the Thermoelectrical Power Plant at Marghera. The experimental installation, operating on the principle of gas energizing, is able to remove simultaneously 40 to 50% of the NOX and about 100% of the SO2 contained in the flue gases. It is expected to achieve better efficiency in the removal of NOX by including in the system a bag filter which should favour removal reaction in the heterogeneous phase of NOX. Particulate concentration at output is between 2 and 5 mg/Nm3. A pulse generator designed and built by Enel was tested; the results were excellent, so work has begun on the preliminary planning of a 200 kW pulse generator that operates on the same principle. (author)

  3. 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.

  4. 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 data...

  5. Isomer shifts of the 6.2-keV gamma-rays of tantalum-181. Chapter 8d

    International Nuclear Information System (INIS)

    The present chapter is divided into two main parts. In the first part, the more general aspects of 181Ta isomer shifts are covered, including an estimation of Δ(r2) from the systematics of isomer shifts in transition metal hosts. The second part is devoted to solid-state applications, such as studies of the isomer-shift dependence on hydrostatic pressure, on temperature, and on impurity atoms, especially hydrogen. (Auth.)

  6. 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.

  7. 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].

  8. 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...

  9. 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。

  10. Study of the collisional destruction of neutral hydrogen atoms in the ground state H(12S) and in the metastable state H(22S) on different rare gas targets in the 0.5 to 3.0 keV level energy range

    International Nuclear Information System (INIS)

    The total destruction cross-sections of H(22S) on rare gases and hydrogen are studied in the energy range 50 to 3000 eV, and the electron loss and electron capture cross-sections from H(12S) and H(22S) in the energy range 0.5 to 3 keV. The de-excitation cross-sections are deduced

  11. 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...

  12. 30 CFR 20.2 - Definitions.

    Science.gov (United States)

    2010-07-01

    ... MINING PRODUCTS ELECTRIC MINE LAMPS OTHER THAN STANDARD CAP LAMPS § 20.2 Definitions. (a) Adequate.... Official notification in writing from MSHA to a responsible organization, stating that upon...

  13. Biology Education Research 2.0

    OpenAIRE

    Dolan, Erin L.

    2015-01-01

    Biology education research (BER) 2.0 has arrived, and is moving the BER community beyond showing that active learning works to understanding the individual and contextual factors that explain and influence biology teaching and learning.

  14. Institutions Struggling with Web 2.0

    OpenAIRE

    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.

  15. Trove: A Government 2.0 Showcase

    OpenAIRE

    Holley, Rose

    2010-01-01

    The presentation demonstrates the features and development which have made Trove a Government 2.0 showcase. These include opening access to information, sharing and collaborating, involving users in development, and a high level of social engagement in the service.

  16. The Konstanz Information Miner 2.0

    OpenAIRE

    Meinl, Thorsten; Cebron, Nicolas; Gabriel, Thomas R.; Dill, Fabian; Kötter, Tobias; Ohl, Peter; Thiel, Kilian; Wiswedel, Bernd; Berthold, Michael R

    2009-01-01

    In December 2008, version 2.0 of the data analysis platform KNIME was released. It includes several new features, which we will describe in this paper. We also provide a short introduction to KNIME for new users.

  17. 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....

  18. Lost in Web 2.0 Cyberspace?

    Science.gov (United States)

    Fallon, Julia

    2008-01-01

    Web 1.0 never left. It's just a term that refers to cyberspace before 2002. People mark the shift from Web 1.0 to 2.0 with the dramatic collapse of Web-based companies whose phenomenal growth was based on the profit potential of a new customer: the Internet user. Generally, Web 1.0 sites have a commercial focus. On the other hand, Web 2.0 reverses…

  19. 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

  20. Best Practices of WEB 2.0

    Directory of Open Access Journals (Sweden)

    G.N.K.Suresh Babu

    2013-03-01

    Full Text Available In this paper the author describes about what is Web 2.0, how It evolves from Web 1.0, differences between Web 1.0, 2.0 and 3.0 and how we can use Web 2.0 in best practice manner. The author analyses how Web 2.0 can be used in Web Personalization and site structure. There is considerable excitement about the notion of 'Web 2.0', particularly among Internet business people. In contrast, there is an almost complete lack of formal literature on the topic. It is important that movements with such energy and potential be subjected to critical attention, and that industry and social commentators have the opportunity to draw on the eCommerce research literature in formulating their views. The author assesses the available information about Web 2.0, with a view to stimulating further work that applies existing theories, proposes new ones, observes and measures phenomena, and tests the theories. The primary interpretation of the concept derives from marketers, but the complementary technical and communitarian perspectives are also considered. A common theme derived from the analysis is that of 'syndication' of content, advertising, storage, effort and identity.

  1. 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.)

  2. 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.

  3. 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....

  4. 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.

  5. Nucleosynthesis confronts an unstable inert 17 keV state

    International Nuclear Information System (INIS)

    We study the cosmological consequences of an inert 17 keV state mixing with the electron neutrino. We find that the nucleosynthesis upper bound on the primordial helium abundance prohibits the existence of such a state, unless its lifetime falls into the range 6x10-4svac-2s. In this range the decay occurs after the chemical decoupling of the electron neutrinos and before the beginning of the nucleosynthesis, with the result that the predicted helium abundance can be lower than what it would be in the standard scenario. (orig.)

  6. Electron inelastic interactions in bioorganic compounds in the energy range of 20 10000 eV

    Science.gov (United States)

    Tan, Z.; Xia, Y.; Liu, X.; Zhao, M.; Ji, Y.; Li, F.; Huang, B.

    2005-09-01

    Systematic calculations of stopping powers (SPs) and mean free paths (MFPs) for 10 bioorganic compounds have been performed for electrons with energies lower than 10 keV, based on dielectric response theory and Penn’s statistical approximation. The exchange effect is also taken into account in the calculations. An empirical approach to obtain an optical energy loss function is presented for those organic compounds without available optical data. Using this method, the calculated values of the optical energy loss function are in good agreement with experimental data. Comparisons of SP and MFP values derived in this study with other published values are presented. Using the described model, the calculated mean ionization potentials agree well with the predictions from Bragg’s rule and the calculated SPs have also been compared with the Bethe Bloch results at an energy of 10 keV.

  7. Measurement of L subshell photoionisation cross sections of Th and U at 22.6, 25.8, 29.2 and 32.9 kev

    Energy Technology Data Exchange (ETDEWEB)

    Santra, S. [Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064 (India); Mitra, D. [Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064 (India); Sarkar, M. [Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064 (India)]. E-mail: manoranjan.sarkar@saha.ac.in; Bhattacharya, D. [Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064 (India)

    2007-10-15

    Bremsstrahlung from an X-ray tube was used to excite secondary targets of Ag, Sn, I and Ba to get nearly monochromatic excitation energies of 22.6, 25.8, 29.2 and 32.9 keV, respectively. Th and U were used as targets. The L X-ray fluorescence cross sections of different lines from the targets have been measured. Of the several methods to obtain L subshell photoionisation cross sections from these fluorescence data, the merits and demerits of four common methods have been explained and the method with least uncertainty was suggested as the best one for such analysis. Following this method, with intensities of the resolved L {sub {gamma}} lines, three L subshell photoionisation cross sections have been obtained using six different sets of atomic parameters. The variation of these cross sections with different atomic parameters has been discussed. For {sigma} {sub 1}, all the derived values are within 30% of one other while for {sigma} {sub 2} and {sigma} {sub 3}, they are within 12%. Measured cross sections have been compared with the data of others and with the theoretical values of Scofield. Finally, the intensity ratios of different L lines have also been compared with available data and the theoretical values. Within experimental errors, our data are in good agreement with the data of others and with the theoretical predictions.

  8. Spectral albedo of photons of initial energies below 100 keV

    Directory of Open Access Journals (Sweden)

    Marković Srpko

    2007-01-01

    Full Text Available This paper shows the results of Monte Carlo simulations of the photon reflection from homogenous plates of the shield materials made of water, aluminum, and iron. Perpendicular incidence of a monoenergetic photon beam of the initial energy of 20 keV up to 100 keV is considered. The numerical experiments were performed using the verified Monte Carlo programs MCNP-4C, FOTELP-2K3, and PENELOPE-2005. As the result, the values of difference number albedo distributed in ten even intervals according to the energy and nine even intervals according to the polar angle of reflected photons were obtained. Out of these data, the spectral albedo coefficients for all three materials and three initial photon energies of 40 keV, 60 keV, and 100 keV were calculated, graphically presented, and analyzed. The values of the spectral albedo determined on the basis of MCNP-4C code were compared to the results of the early simulations of the photon reflection performed in Russia and in the USA. Also, with the help of MCNP-4C program, the yield of fluorescent photons to the spectrum of the reflected radiation was registered, which can be seen in the graphs in the form of the peak at the energy of 7.112 keV only at the shielding plates made of iron.

  9. Spectral albedo of photons of initial energies below 100 keV

    International Nuclear Information System (INIS)

    This paper shows the results of Monte Carlo simulations of the photon reflection from homogenous plates of the shield materials made of water, aluminum, and iron. Perpendicular incidence of a monoenergetic photon beam of the initial energy of 20 keV up to 100 keV is considered. The numerical experiments were performed using the verified Monte Carlo programs MCNP-4C, FOTELP-2K3, and PENELOPE-2005. As the result, the values of difference number albedo distributed in ten even intervals according to the energy and nine even intervals according to the polar angle of reflected photons were obtained. Out of these data, the spectral albedo coefficients for all three materials and three initial photon energies of 40 keV, 60 keV, and 100 keV were calculated, graphically presented, and analyzed. The values of the spectral albedo determined on the basis of MCNP-4C code were compared to the results of the early simulations of the photon reflection performed in Russia and in the USA. Also, with the help of MCNP-4C program, the yield of fluorescent photons to the spectrum of the reflected radiation was registered, which can be seen in the graphs in the form of the peak at the energy of 7.112 keV only at the shielding plates made of iron. (author)

  10. 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。

  11. 20 CFR 302.2 - Definitions.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Definitions. 302.2 Section 302.2 Employees... period. If an employee is eligible for payment of extended benefits, the benefit year ending date for such employee will be June 30, or the last day of his or her extended benefit period, whichever date...

  12. 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...

  13. 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...

  14. 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.

  15. 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

  16. Web 2.0 for IPTV

    OpenAIRE

    Leung, Simon; Pettersson, Johan

    2008-01-01

    This master’s thesis project concerns implementing and evaluating Web 2.0 services for IPTV. This thesis project was carried out at Accedo Broadband during the period August to December 2008. Accedo Broadband is a provider of interactive applications and on-demand content for IPTV. The report will analyze, specify, create, and evaluate a solution for adding Web 2.0 functionality from the most popular sites as IPTV content. We will evaluate several different web services APIs and examine how s...

  17. EcoMark 2.0

    DEFF Research Database (Denmark)

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

    2015-01-01

    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...

  18. 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.

  19. Library 2.0探讨%On Library 2.0

    Institute of Scientific and Technical Information of China (English)

    黄国忠; 谢美萍

    2007-01-01

    Library2.0是Web2.0技术/理念应用于图书馆所延伸出来的一种新的服务理念,该理念首先发端于图资博客圈内.文章总结、分析了各位图资博客的观点,阐述了Library2.0/Web2.0的基本理念及如何构建Library 2.0的基本思想,并对2.0时代的图书馆精神作了一个新的诠释.

  20. 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.

  1. Herwig++ 2.0beta Release Note

    OpenAIRE

    Gieseke, Stefan; Grellscheid, D.; Ribon, Alberto; Richardson, P.; Seymour, Michael H.; Stephens, Phil; Webber, Bryan R

    2006-01-01

    A new release of the Monte Carlo program Herwig++ (version 2.0beta) is now available. The main new feature is the extension of the program to include simple hadron-hadron processes including the initial-state parton shower.

  2. The PLATO 2.0 mission

    NARCIS (Netherlands)

    H. Rauer; al et; S. Hekker

    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

  3. 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,

  4. 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

  5. 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…

  6. 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.

  7. IntelliGrow 2.0

    DEFF Research Database (Denmark)

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

    2008-01-01

    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...

  8. 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.

  9. 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.

  10. A measurement of the electron-hole pair creation energy and the Fano factor in silicon for 5.9 keV X-rays and their temperature dependence in the range 80-270 K

    International Nuclear Information System (INIS)

    A measurement of the energy ω to create an electron-hole pair and its temperature dependence between 80 and 270 K has been made using a small Si p-i-n diode and 5.9 keV X-rays. A value of 3.73±0.09 eV with a gradient of -0.0131±0.0004% K-1 was found. The photo-peak dispersion D was also measured and from the values between 110 K and 235 K, the product ωF was found to be 0.441±0.005 eV. This is consistent with a constant Fano factor F of 0.118±0.004

  11. 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.

  12. Using Web 2.0 for Learning in the Community

    Science.gov (United States)

    Mason, Robin; Rennie, Frank

    2007-01-01

    This paper describes the use of a range of Web 2.0 technologies to support the development of community for a newly formed Land Trust on the Isle of Lewis, in NW Scotland. The application of social networking tools in text, audio and video has several purposes: informal learning about the area to increase tourism, community interaction,…

  13. 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.

  14. 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 %.

  15. Teaching PBL with Web 2.0

    DEFF Research Database (Denmark)

    Dohn, Nina Bonderup; Buus, Lillian

    2013-01-01

    , 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......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...... 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...

  16. 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。

  17. 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...

  18. 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...

  19. 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.

  20. Non-dissociative and dissociative ionization of N{sub 2}, CO, CO{sub 2}, and CH{sub 4} by impact of 50-6000 keV protons and antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Knudsen, H.; Mikkelsen, U.; Paludan, K. [Aarhus Univ. (Denmark). Inst. for Fysik og Astronomi; Kirsebom, K.; Moeller, S.P.; Uggerhoej, E. [Aarhus Univ. (Denmark). Inst. for Synchrotron Radiation; Slevin, J. [Saint Patrick`s Coll., Maynooth (Ireland). Dept. of Experimental Physics; Charlton, M. [University Coll., London (United Kingdom). Dept. of Physics and Astronomy; Morenzoni, E. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1995-08-28

    Measurements of the cross section for non-dissociative single ionization and the cross sections for the creation of charged fragments have been performed for 50-6000 keV antiproton and proton impact on N{sub 2}, CO, CO{sub 2}, and CH{sub 4}. The results support the understanding of the ionization phenomenon that has been achieved via measurements with fundamental charged particles on atoms. The present high-energy antiproton fragmentation data supply a stringent test of the validity of the published electron-impact fragmentation data which, unfortunately, most of them fail. (Author).

  1. 58Ni + n transmission, differential elastic scattering and capture measurements and analysis from 5 to 813 keV

    International Nuclear Information System (INIS)

    High-resolution neutron measurements for 58Ni-enriched targets were made at the Oak Ridge Electron Linear Accelerator (ORELA) from 100 eV to ∼20 MeV in transmission, from 10 keV to 5 MeV in differential elastic, and from 2.5 keV to 5 MeV in capture. The transmission data were analyzed from 10 to 813 keV with the multilevel R-matrix code SAMMY which uses Bayes' theorem for the fitting process. This code provides energies and neutron widths of the resonances inside the 10- to 813-keV region as well as a possible parameterization for resonances external to that region to describe the smooth cross section from 10 to 813 keV. The differential elastic data at different scattering angles were compared to theoretical calculations from 30 to 813 keV using an R-matrix code based on the Blatt-Biedenharn formalism. Various combinations of spin and parity were tried to predict cross sections for the well defined /ell/ > 0 resonances, and comparison with the data then provided spin and parity assignments for most of these resonances. the capture data were analyzed from 5 to 450 keV with a least-squares fitting code using the Breit-Wigner formula. In this energy region 30% more resonances were observed in the capture data than in the transmission data. 55 refs., 44 figs., 3 tabs

  2. 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. PMID:23592622

  3. 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.

  4. A new approach for precise measurements of keV neutron capture cross sections: The examples of 93Nb, 103Rh, and 181Ta

    International Nuclear Information System (INIS)

    A new experimental method has been implemented for precise measurements of neutron capture cross sections in the energy range from 3 to 200 keV. Neutrons are produced via the 7Li(p,n)7Be reaction using a pulsed 3 MV Van de Graaff accelerator. The neutron energy is determined by the time of flight technique using flight paths of less than 1 m. Capture events are detected with the Karlsruhe 4π Barium Fluoride Detector. This detector is characterized by a resolution in gamma-ray energy of 14% at 662 keV and 7% at 2.5 MeV, a time resolution of 500 ps, and a peak efficiency of 90% at 1 MeV. Capture events are registered with ≅ 95% probability above a gamma-ray threshold of 2.5 MeV. The combined effect of the relatively short primary flight path, the 10 cm inner radius of the detector sphere, and of the low capture cross section of BaF2 allows to discriminate the main background due to capture of sample scattered neutrons in the scintillator via time of flight, leaving part of the neutron energy range completely undisturbed. The high efficiency and good energy resolution for capture gamma-rays yields a further reduction of this background by using only the relevant energy channels for data evaluation. In the first measurements with the new detector, the neutron capture cross sections of 93Nb, 103Rh, and 181Ta were determined in the energy range from 3 to 200 keV relative to gold as a standard. The cross section ratios could be determined with overall systematic uncertainties of 0.7 to 0.8%; statistical uncertainties were less than 1% in the energy range from 20 to 100 keV, if the data are combined in 20 keV wide bins. The necessary sample masses were of the order of one gram. Further improvements with respect to sensitivity and accuracy are discussed. (orig.)

  5. r-Java 2.0: the nuclear physics

    OpenAIRE

    Kostka, M.; N. Koning; 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 nucle...

  6. 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

  7. Evaluation of 242Pu data for the incident neutron energy range 5-20 MeV

    International Nuclear Information System (INIS)

    Models, procedures and parameters are presented for the calculation of neutron cross sections, the neutron angular distributions and the neutron energy distributions of 242Pu in the energy range 5-20 MeV. The interaction takes place through direct interaction and compound nucleus mechanism. For heavy deformed nucleus the direct interaction was treated with the coupled channel process, using the ECIS code. For the compound nucleus mechanism, a statistical treatment was used for fission, neutron elastic and inelastic scattering, radiative capture, (n,2n), (n,3n), (n,4n) cross section calculations, using the GNASH code. (R.P.)

  8. 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.

  9. 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.

  10. LA WEB 2.0 EN ESCENA.

    OpenAIRE

    Raúl Santiago Campión; Fermín Navaridas Nalda

    2012-01-01

    En este artículo pretendemos desarrollar un análisis crítico sobre los denominados entornos Web 2.0. Para ello comenzaremos un recorrido "histórico" sobre el origen del término para después realizar una descripción de sus características, lo que nos permitirá abordar su funcionamiento técnico. Todo ello nos debe servir para tratar de comprender si nos encaminamos hacia el denominado modelo "3.0". Concluiremos con una crítica constructiva de algunos aspectos relevantes que se han venido mencio...

  11. La web 2.0 en escena

    OpenAIRE

    Santiago Campión, Raúl; Fermín NAVARIDAS NALDA

    2012-01-01

    En este artículo pretendemos desarrollar un análisis crítico sobre los denominados entornos Web 2.0. Para ello comenzaremos un recorrido "histórico" sobre el origen del término para después realizar una descripción de sus características, lo que nos permitirá abordar su funcionamiento técnico. Todo ello nos debe servir para tratar de comprender si nos encaminamos hacia el denominado modelo "3.0". Concluiremos con una crítica constructiva de algunos aspectos relevantes que se han venido mencio...

  12. Web 2.0 and Higher Education

    OpenAIRE

    Cunha, Luís António Morão Pinto Simões da

    2012-01-01

    Tese apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Doutor em Ciências da Informação, especialização em Sistemas e Tecnologias da Informação. The emergence of tools like Blogs or Wikis made the creation of online contents much easier than before. The evolving concept of Web 2.0 emphasizes the fact that the user can now easily participate in the delivery of Web contents, taking advantage of existing tools. In this thesis, two empirical stud...

  13. 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.

  14. [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.

  15. 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.

  16. 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.

  17. Cross section for induced L X-ray emission by protons of energy <400 keV

    Energy Technology Data Exchange (ETDEWEB)

    Mohan, Harsh, E-mail: mohan_harsh@yahoo.com [Physics Department, M.L.N. College, Yamuna Nagar 135 001, Haryana (India); Jain, Arvind Kumar [Physics Department, M.L.N. College, Yamuna Nagar 135 001, Haryana (India); Kaur, Mandeep [Physics Department, M.L.N. College, Yamuna Nagar 135 001, Haryana (India); Physics Department, Punjabi University, Patiala 147 002, Punjab (India); Singh, Parjit S. [Physics Department, Punjabi University, Patiala 147 002, Punjab (India); Sharma, Sunita [Chemistry Department, M.L.N. College, Yamuna Nagar 135 001, Haryana (India)

    2014-08-01

    In performing ion beam analysis, cross section for induced L X-ray emission plays a crucial role. There are different approaches by which these can be found experimentally or can be calculated theoretically based on various models. L X-ray production cross sections for Bi with protons in the energy range 260–400 keV at the interval of 20 keV are measured. These are compared with calculations obtained on the basis of current prevailing theories ECPSSR and ECPSSR-UA. Their importance in understanding this phenomenon and existing arguments in this regard will be highlighted.

  18. 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.

  19. M2-Branes And The (2,0) Superalgebra

    CERN Document Server

    Lambert, Neil

    2016-01-01

    We present a generalization of the six-dimensional (2,0) system of arXiv:1007.2982 to include a constant abelian 3-form. For vanishing 3-form this system is known to provide a variety descriptions of parallel M5-branes. For a particular choice of 3-form the system is shown to reduce to that of two M2-branes. Thus this generalised (2,0) system provides a unified description of two parallel M2-branes or M5-branes.

  20. Detection of 1 - 100 keV x-rays from high intensity, 500 fs laser- produced plasmas using charge-coupled devices

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, J.; Young, B.K.F.; Conder, A.D.; Stewart, R.E.

    1996-01-01

    We describe a compact, vacuum compatible, large format, charge- coupled device (CCD) camera for scientific imaging and detection of 1- 100 keV x rays in experiments at LLNL JANUS-1ps laser. A standard, front-illuminated, multi-pin phase device with 250 k electron full well capacity, low dark current (10 pA/cm{sup 2} at 20 C) and low read noise (5 electron rms) is cooled to -35 C to give the camera excellent 15-bit dynamic range and signal-to-noise response. Intensity and x-ray energy linear response were determined for optical and x-ray (<65 keV) photons and are in excellent agreement. Departure from linearity was less than 0.7%. Inherent linearity and energy dispersive characteristics of CCD cameras are well suited for hard x-ray photon counting. X-rays absorbed within the depletion and field-free regions can be distinguished by studying the pulse height spectrum. Results are presented for the detection of 1-100 keV Bremsstrahlung continuum, K-shell and L-shell fluorescence spectra emitted from high intensity (10{sup 18}W cm{sup -2}), 500 fs laser- produced plasmas.

  1. Angular dependence of L X-rays emission for Ag by 10 keV electron-impact

    Science.gov (United States)

    Wang, Xing; Xu, Zhongfeng; Zhang, Ying; Ma, Chao; Zhu, Chengwei

    2016-08-01

    The characteristic X-ray intensities of Ag-Lα, Lβ1, Lβ2 and Lγ1 are measured in electron-impact ionization at energy of 10 keV. The emission angle in this work ranges from 0° to 20° at interval of 5°. The angular dependence of L X-ray intensity ratios has been investigated for Lα / Lβ1, Lβ2 / Lβ1 and Lγ1 / Lβ1. It is found from the experimental results that the emissions of Lβ1, Lβ2 and Lγ1 X-rays are spatially isotropic, while the Lα X-rays exhibit anisotropic emission. Consequently, the alignment behavior of vacancy states is discussed with thorough analysis of vacancy transfer process.

  2. The Space Complexity of 2-Dimensional Approximate Range Counting

    DEFF Research Database (Denmark)

    Wei, Zhewei; Yi, Ke

    2013-01-01

    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 ∩ ...

  3. Web 2.0

    OpenAIRE

    Boistel, Philippe

    2013-01-01

    Avec le développement du Web 2.0, les entreprises sont de plus en plus sollicitées et parfois mises en accusation sur la Toile. La conséquence majeure se porte sur l’e-réputation qui peut être considérée comme la réputation ressortant des conversations issues d’Internet. Les entreprises cherchent à gérer cette e-réputation et les conséquences de ces mises en accusation sur les cours boursiers, les candidatures, et les ventes. A partir de quatre études de cas français, l’auteur analyse comment...

  4. 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.

  5. LA WEB 2.0 EN ESCENA.

    Directory of Open Access Journals (Sweden)

    Raúl Santiago Campión

    2012-01-01

    Full Text Available En este artículo pretendemos desarrollar un análisis crítico sobre los denominados entornos Web 2.0. Para ello comenzaremos un recorrido "histórico" sobre el origen del término para después realizar una descripción de sus características, lo que nos permitirá abordar su funcionamiento técnico. Todo ello nos debe servir para tratar de comprender si nos encaminamos hacia el denominado modelo "3.0". Concluiremos con una crítica constructiva de algunos aspectos relevantes que se han venido mencionando en torno al concepto de web colaborativa.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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).

  11. 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...

  12. 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.

  13. 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.

  14. Problems for (2,0) compactifications

    International Nuclear Information System (INIS)

    Several theoretical and phenomenological problems are exposed which impede the construction of realistic low-energy models based on the superstring using manifolds for which the gauge and spin connections are not identified (A not equal to ω), and the world-sheet σ-model has (2,0) supersymmetry. Single worldsheet instantanons generate an effective scalar potential which prevents generic manifolds of this type from being solutions to the equations of motion. They also give large supersymmetry-breaking mass parameters O(m/sub p/) to gauge non-singlet fields. The Green-Schwarz modification to the anti-symmetric tensor field strength may not absorb anomalies if ω not equal to A. It is difficult to obtain satisfactory mixing among the supersymmetric Weinberg-Salem Higgs fields, which requires an SU(3) x SU(2) x U(1) singlet field N with vacuum expectation value x identical to = (m/sub W/). A Yukawa coupling λ N3 would yield x = O(m/sub W/), but at the expense of cosmologically unacceptable domain walls. If there is no such Yukawa coupling, the natural value for x is O(m/sub P/)

  15. 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...

  16. 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...

  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. 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…

  19. FLUTAN 2.0. Input specifications

    International Nuclear Information System (INIS)

    FLUTAN is a highly vectorized computer code for 3D fluiddynamic and thermal-hydraulic analyses in Cartesian or cylinder coordinates. It is related to the family of COMMIX codes originally developed at Argonne National Laboratory, USA, and particularly to COMMIX-1A and COMMIX-1B, which were made available to FZK in the frame of cooperation contracts within the fast reactor safety field. FLUTAN 2.0 is an improved version of the FLUTAN code released in 1992. It offers some additional innovations, e.g. the QUICK-LECUSSO-FRAM techniques for reducing numerical diffusion in the k-ε turbulence model equations; a higher sophisticated wall model for specifying a mass flow outside the surface walls together with its flow path and its associated inlet and outlet flow temperatures; and a revised and upgraded pressure boundary condition to fully include the outlet cells in the solution process of the conservation equations. Last but not least, a so-called visualization option based on VISART standards has been provided. This report contains detailed input instructions, presents formulations of the various model options, and explains how to use the code by means of comprehensive sample input. (orig.)

  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. 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…

  2. 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...

  3. 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

  4. The double ionisation of hydrogen by 5-30 keV protons

    International Nuclear Information System (INIS)

    The energy and angular distribution of pairs of fragment protons produced in H+-H2 collisions has been investigated in the energy range 5-30 keV. It is shown that the energy distribution is a simple transformation of the ground-state wavefunction of H2 and an experimental determination of the ground-state probability density distribution is presented. Total and differential double ionisation cross sections are found to be in accord with earlier measurements. (author)

  5. 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...

  6. The r-Java 2.0 code: nuclear physics

    Science.gov (United States)

    Kostka, M.; Koning, N.; Shand, Z.; Ouyed, R.; Jaikumar, P.

    2014-08-01

    Aims: We present r-Java 2.0, a nucleosynthesis code for open use that performs r-process calculations, along with 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 and studying individual nucleosynthesis processes. Results: In this paper we discuss enhancements to this version of r-Java, especially the ability to solve the full reaction network. The sophisticated fission methodology incorporated in r-Java 2.0 that includes three fission channels (beta-delayed, neutron-induced, and spontaneous fission), along with 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 studied. The role of Coulomb interactions in NSE abundances is shown to be significant, supporting previous findings. A comparative analysis was undertaken during the development of r-Java 2.0 whereby we reproduced the results found in the literature from three other r-process codes. This code is capable of simulating the physical environment of the high-entropy wind around a proto-neutron star, the ejecta from a neutron star merger, or the relativistic ejecta from a quark nova. Likewise the users of r-Java 2.0 are given the freedom to define a custom environment. This software provides a platform for comparing proposed r-process sites.

  7. One-sided imaging of large, dense objects using the 511 keV photons from induced pair production

    Energy Technology Data Exchange (ETDEWEB)

    Tavora, L.M.; Gilboy, W.B.; Morton, E.J. [Univ. of Surrey, Guildford (United Kingdom). Physics Dept.; Morgado, R.E.; Estep, R.J.; Rawool-Sullivan, M. [Los Alamos National Lab., NM (United States)

    1998-03-01

    The use of annihilation photons from photon-induced electron-positron pair production as a means of inspecting objects when only one side is accessible is described. The Z2 dependence of the pair production cross section and the high penetration of 511 keV photons suggest that this method should be capable of localizing high Z materials in lower Z matrices. The experimental results for the dependence of the back streaming photon yield on Z indicate that dynamic ranges of the order of 20 may be obtained for materials with 4 < Z < 82. Results for point to point images obtained in line scans of representative geometries are also shown. Simulation studies based on the EGS4 Monte Carlo code were also performed and their results show an agreement with experimental data of the order of 5%.

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. Media masters and grassroot art 2.0 on Youtube

    OpenAIRE

    Richard, Birgit

    2011-01-01

    Communication in the Web 2.0 context mainly works through images. The online video platform YouTube uses this form of visual communication and makes art forms of Western societies visible through their online videos. YouTube, as cultural reservoir and visual archive of moving images, accommodates the whole range of visualising creative processes – from artistic finger exercises to fine arts. A general characteristic of YouTube is the publishing of small everyday gestures of the ‘big ones’ (po...

  14. Primary standard for the number concentration of liquid-borne particles in the 10 to 20 µm diameter range

    International Nuclear Information System (INIS)

    The national primary standard for the number concentration of liquid-borne particles in the 10 to 20 µm diameter range has been developed at the National Institute of Advanced Industrial Science and Technology (AIST), Japan. The standard consists of a total number counting type flow cytometer (T-FCM) and an electronic balance. The T-FCM is a commercial flow cytometer modified so that the total number of particles in an aqueous suspension sampled in a test tube can be counted, and the electronic balance is used to determine the mass of the suspension. This standard is intended to be used for calibrating commercial standard suspensions of monodisperse polystyrene latex (PSL) particles. The measurand in the calibration is the mass-based number concentration (the particle number in a unit mass of a suspension), and the calibration capability covers the concentration range from 5 × 102 to 2 × 106 particles g−1. When the concentration of the suspension is higher than 2 × 103 particles g−1, the suspension is first diluted to about 1 × 103 particles g−1 to suppress the coincidence loss in particle counting by the T-FCM. The validity of the calibration with the T-FCM was examined by comparison with an independent method in which a scanning electron microscope (SEM) was used to determine the number concentration of particles deposited on a silicon wafer. For a suspension of 10 µm PSL particles with a concentration of approximately 1 × 106 particles g−1, the concentration values determined by the T-FCM and SEM methods were 1.042 × 106 and 1.035 × 106 particles g−1, respectively: The difference was less than 0.7%. The relative expanded uncertainty of the measurement by the T-FCM method with the coverage factor k = 2 was 4.4%

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

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Marcel; Keskinbora, Kahraman; Grévent, Corinne, E-mail: grevent@is.mpg.de [Max Planck Institute for Intelligent Systems, Heisenbergstrasse 3, D-70569 Stuttgart (Germany); Szeghalmi, Adriana [Friedrich-Schiller-Universität Jena, Albert-Einstein-Strasse 15, D-07745 Jena (Germany); Knez, Mato [CIC nanoGUNE Consolider, Tolosa Hiribidea 76, E-20018 Donostia-San Sebastian (Spain); Basque Foundation for Science, Alameda Urquijo 36-5, E-48011 Bilbao (Spain); Weigand, Markus [Max Planck Institute for Intelligent Systems, Heisenbergstrasse 3, D-70569 Stuttgart (Germany); Snigirev, Anatoly; Snigireva, Irina [European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP 220, F-38043 Grenoble (France); Schütz, Gisela [Max Planck Institute for Intelligent Systems, Heisenbergstrasse 3, D-70569 Stuttgart (Germany)

    2013-05-01

    The fabrication and performance of multilayer Al{sub 2}O{sub 3}/Ta{sub 2}O{sub 5} Fresnel zone plates in the hard X-ray range and a discussion of possible future developments considering available materials are reported. 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. Al{sub 2}O{sub 3}/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.

  16. 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.

  17. 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...

  18. Irradiation of biological molecules (DNA and RNA bases) by proton impact in the velocity range of the Bragg peak (20-150 keV/amu)

    International Nuclear Information System (INIS)

    The aim of this work was to study the ionization of DNA and RNA base molecules by proton impact at energies between 20 and 150 keV/amu. The experiments developed over the course of this project made it possible not only to study the fragmentation of uracil, thymine, adenine, and cytosine, but also to measure absolute cross sections for different ionization processes initiated by proton interactions with these important biological molecules. Firstly, the experimental system enabled the contributions of two key ionization processes to be separated: direct ionization and electron capture. The corresponding mass spectra were measured and analyzed on an event-by-event basis. For uracil, the branching ratios for these two processes were measured as function of the projectile velocity. Secondly, we have developed a system to measure absolute cross sections for the electron capture process. The production rate of neutral atoms compared to protons was measured for the four biological molecules: uracil, cytosine, thymine, and adenine at different vaporization temperatures. This production rate varies as a function of the thickness of the target jet traversed by the protons. Accordingly, a deposit experiment was developed in order to characterize the density of molecules in the targeted gas jets. Theoretical and experimental study of the total effusion and density-profile of the gaseous molecular beams enabled us to deduce the thickness of the target jets traversed by the protons. Thus it was possible to determine absolute cross sections for the ionization of each of the four isolated biological molecules by 80 keV protons impact. To our knowledge, this work provides the first experimental absolute cross sections for DNA and RNA base ionization processes initiated by proton impact in the velocity range corresponding to the Bragg peak. (author)

  19. 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.

  20. Calculation for Improvement of 350 keV Electron Accelerator

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The main problem of the 350 keV electric accelerator is that the accelerator can not output 20 mA for a long time otherwise the vacuum become bad. The reason is that part of the beam bomb on the scanning box and increase the temperature immediately,

  1. 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...

  2. 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

  3. Search for admixture of heavy neutrinos with masses between 5 and 55 keV

    OpenAIRE

    Markey, J.; Boehm, F.

    1985-01-01

    Using a magnetic spectrometer at a momentum resolution of 0.3%, we have studied the beta spectrum from 35S. We do not see evidence for the admixture of a heavy neutrino to the usual light (m~0) ν̃e accompanying beta decay, in the mass range between 5 and 50 keV, with a limit for the mixing strength of |U|2

  4. 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...

  5. Steady State Sputtering Yields and Surface Compositions of Depleted Uranium and Uranium Carbide bombarded by 30 keV Gallium or 16 keV Cesium Ions

    International Nuclear Information System (INIS)

    Depleted uranium that included carbide inclusions was sputtered with 30keV gallium ions or 16kev cesium ions to depths much greater than the ions’ range, i.e. using steady state sputtering. The recession of both the uranium’s and uranium carbide’s surfaces and the ion corresponding fluences were used to determine the steady state target sputtering yields of both uranium and uranium carbide, i.e. 6.3 atoms of uranium and 2.4 units of uranium carbide eroded per gallium ion, and 9.9 uranium atoms and 3.65 units of uranium carbide eroded by cesium ions. The steady state surface composition resulting from the simultaneous gallium or cesium implantation and sputter-erosion of uranium and uranium carbide were calculated to be U86Ga14, (UC)70Ga30 and U81Cs9, (UC)79Cs21, respectively.

  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. 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.

  8. 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.

  9. 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…

  10. 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...

  11. 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.

  12. Angular distribution measurements of sup 1 sup 2 C(d,p) sup 1 sup 3 C reaction below 350 keV deuteron energies using nuclear track detectors

    CERN Document Server

    Al-Jarallah, M I; Abu-Jarad, F A

    1999-01-01

    Angular distribution of sup 1 sup 2 C(d,p) sup 1 sup 3 C reaction were measured at 13 angles for 223, 308 and 332 keV deuteron energies using nuclear track detectors (NTDs). The measurements were carried out over 25 to 164 degree angles in 10 degree steps using scattering chamber of 80 deg. beam line of the 350 kV accelerator. In each run, a semiconductor surface barrier (SSB) monitor detector, masked by thin mylar foil, was placed at +164 degree and was used for flux and target thickness normalization between two runs of each angular distribution. In order to check the performance of the NTDs, angular distribution measurement was also repeated at 250 keV deuteron energy at which data had already been taken with surface barrier detectors. The angular distribution measured by NTDs was found comparable with measurements carried out using SSB detectors which indicate the possibility of using NTDs instead of expensive SSB detectors. The angular distributions of sup 1 sup 2 C(d,p) sup 1 sup 3 C reaction at 223, 25...

  13. 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.

  14. Web 2.0 and Social Software

    DEFF Research Database (Denmark)

    Ryberg, Thomas

    2006-01-01

    Presentation given at the MINE workshop - a 2-day workshop for students to create innovative products to be presented to the public during Culture Night 13th of October......Presentation given at the MINE workshop - a 2-day workshop for students to create innovative products to be presented to the public during Culture Night 13th of October...

  15. 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.

  16. 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.

  17. 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.

  18. 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……

  19. Effects of the compounds 2-methoxynaphthoquinone, 2-propoxynaphthoquinone, and 2-isopropoxynaphthoquinone on ecdysone 20-monooxygenase activity.

    Science.gov (United States)

    Mitchell, Martin J; Brescia, Aaron I; Smith, Stan L; Morgan, E David

    2007-09-01

    The effects of the natural compound 2-methoxy-1,4-naphthoquinone, isolated from the leaves of Impatiens glandulifera and the synthetic compounds 2-propoxy-1,4-naphthoquinone and 2-isopropoxy-1,4-naphthoquinone on ecdysone 20-monooxygenase (E-20-M) activity were examined in three insect species. Homogenates of wandering stage third instar larvae of Drosophila melanogaster, or abdomens from adult female Aedes aegypti, or fat body or midgut from fifth instar larvae of Manduca sexta were incubated with radiolabelled ecdysone and increasing concentrations (from 1 x 10(-8) to 1 x 10(-3) M) of the three compounds. All three compounds were found to inhibit in a dose-dependent fashion the E-20-M activity in the three insect species. The concentration of these compounds required to elicit a 50% inhibition of this steroid hydroxylase activity in the three insect species examined ranged from approximately 3 x 10(-5) to 7 x 10(-4) M. PMID:17694563

  20. 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...

  1. Analysis of the TMI-2 source range detector response

    International Nuclear Information System (INIS)

    In the first few hours following the TMI-2 accident large variations (factors of 10-100) in the source range (SR) detector response were observed. The purpose of this analysis was to quantify the various effects which could contribute to these large variations. The effects evaluated included the transmission of neutrons and photons from the core to detector and the reduction in the multiplication of the Am-Be startup sources, and subsequent reduction in SR detector response, due to core voiding. A one-dimensional ANISN slab model of the TMI-2 core, core externals, pressure vessel and containment has been constructed for calculation of the SR detector response and is presented

  2. Birding 2.0: Citizen Science and Effective Monitoring in the Web 2.0 World

    Directory of Open Access Journals (Sweden)

    Yolanda F. Wiersma

    2010-12-01

    Full Text Available The amateur birding community has a long and proud tradition of contributing to bird surveys and bird atlases. Coordinated activities such as Breeding Bird Atlases and the Christmas Bird Count are examples of "citizen science" projects. With the advent of technology, Web 2.0 sites such as eBird have been developed to facilitate online sharing of data and thus increase the potential for real-time monitoring. However, as recently articulated in an editorial in this journal and elsewhere, monitoring is best served when based on a priori hypotheses. Harnessing citizen scientists to collect data following a hypothetico-deductive approach carries challenges. Moreover, the use of citizen science in scientific and monitoring studies has raised issues of data accuracy and quality. These issues are compounded when data collection moves into the Web 2.0 world. An examination of the literature from social geography on the concept of "citizen sensors" and volunteered geographic information (VGI yields thoughtful reflections on the challenges of data quality/data accuracy when applying information from citizen sensors to research and management questions. VGI has been harnessed in a number of contexts, including for environmental and ecological monitoring activities. Here, I argue that conceptualizing a monitoring project as an experiment following the scientific method can further contribute to the use of VGI. I show how principles of experimental design can be applied to monitoring projects to better control for data quality of VGI. This includes suggestions for how citizen sensors can be harnessed to address issues of experimental controls and how to design monitoring projects to increase randomization and replication of sampled data, hence increasing scientific reliability and statistical power.

  3. 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.

  4. NASA Taxonomy 2.0 Project Overview

    Science.gov (United States)

    Dutra, Jayne; Busch, Joseph

    2004-01-01

    This viewgraph presentation reviews the project to develop a Taxonomy for NASA. The benefits of this project are: Make it easy for various audiences to find relevant information from NASA programs quickly, specifically (1) Provide easy access for NASA Web resources (2) Information integration for unified queries and management reporting ve search results targeted to user interests the ability to move content through the enterprise to where it is needed most (3) Facilitate Records Management and Retention Requirements. In addition the project will assist NASA in complying with E-Government Act of 2002 and prepare NASA to participate in federal projects.

  5. 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.

  6. 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

  7. 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

  8. 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.

  9. SOURCE 2.0 model development: UO2 thermal properties

    International Nuclear Information System (INIS)

    During analysis of CANDU postulated accidents, the reactor fuel is estimated to experience large temperature variations and to be exposed to a variety of environments from highly oxidized to mildly reducing. The exposure of CANDU fuel to these environments and temperatures may affect fission product releases from the fuel and cause degradation of the fuel thermal properties. The SOURCE 2.0 project is a safety analysis code which will model the necessary mechanisms required to calculate fission product release for a variety of accident scenarios, including large break loss of coolant accidents (LOCAs) with or without emergency core cooling. The goal of the model development is to generate models which are consistent with each other and phenomenologically based, insofar as that is possible given the state of theoretical understanding

  10. 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.

  11. 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

  12. JUNGFRAU 0.2: prototype characterization of a gain-switching, high dynamic range imaging system for photon science at SwissFEL and synchrotrons

    Science.gov (United States)

    Jungmann-Smith, J. H.; Bergamaschi, A.; Cartier, S.; Dinapoli, R.; Greiffenberg, D.; Johnson, I.; Maliakal, D.; Mezza, D.; Mozzanica, A.; Ruder, Ch; Schaedler, L.; Schmitt, B.; Shi, X.; Tinti, G.

    2014-12-01

    JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional pixel detector for photon science applications at free electron lasers and synchrotron light sources. It is developed for the SwissFEL currently under construction at the Paul Scherrer Institute, Switzerland. Characteristics of this application-specific integrating circuit readout chip include single photon sensitivity and low noise over a dynamic range of over four orders of magnitude of photon input signal. These characteristics are achieved by a three-fold gain-switching preamplifier in each pixel, which automatically adjusts its gain to the amount of charge deposited on the pixel. The final JUNGFRAU chip comprises 256 × 256 pixels of 75 × 75 μm2 each. Arrays of 2 × 4 chips are bump-bonded to monolithic detector modules of about 4 × 8 cm2. Multi-module systems up to 16 Mpixels are planned for the end stations at SwissFEL. A readout rate in excess of 2 kHz is anticipated, which serves the readout requirements of SwissFEL and enables high count rate synchrotron experiments with a linear count rate capability of > 20 MHz/pixel. Promising characterization results from a 3.6 × 3.6 mm2 prototype (JUNGFRAU 0.2) with fluorescence X-ray, infrared laser and synchrotron irradiation are shown. The results include an electronic noise as low as 100 electrons root-mean-square, which enables single photon detection down to X-ray energies of about 2 keV. Noise below the Poisson fluctuation of the photon number and a linearity error of the pixel response of about 1% are demonstrated. First imaging experiments successfully show automatic gain switching. The edge spread function of the imaging system proves to be comparable in quality to single photon counting hybrid pixel detectors.

  13. Marketing 2.0: A new marketing strategy

    OpenAIRE

    Domenico CONSOLI; Musso, Fabio

    2010-01-01

    The advent of Web 2.0 and its collaborative tools (forums, chat, blogs, wikis) simplified the interaction among various business subjects (company, customers, suppliers). A new model of Enterprise 2.0 communicates interactively with all stakeholders, cooperate with them, listen, create, share and capitalize knowledge. Web 2.0 enhances customer relationships and supports, fully, developments in the field of marketing: from advertisement to participation, from social networking to mobile comm...

  14. 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...

  15. 1-to 10-keV x-ray backlighting of annular wire arrays on the Sandia Z-machine using bent-crystal imaging techniques.

    Energy Technology Data Exchange (ETDEWEB)

    Rambo, Patrick K.; Wenger, David Franklin; Bennett, Guy R.; Sinars, Daniel Brian; Smith, Ian Craig; Porter, John Larry, Jr.; Cuneo, Michael Edward; Rovang, Dean Curtis; Anderson, Jessica E.

    2003-07-01

    Annular wire array implosions on the Sandia Z-machine can produce >200 TW and 1-2 MJ of soft x rays in the 0.1-10 keV range. The x-ray flux and debris in this environment present significant challenges for radiographic diagnostics. X-ray backlighting diagnostics at 1865 and 6181 eV using spherically-bent crystals have been fielded on the Z-machine, each with a {approx}0.6 eVspectral bandpass, 10 {micro}m spatial resolution, and a 4 mm by 20mm field of view. The Z-Beamlet laser, a 2-TW, 2-kJ Nd:glass laser({lambda} = 527 nm), is used to produce 0.1-1 J x-ray sources for radiography. The design, calibration, and performance of these diagnostics is presented.

  16. 1- to 10-keV x-ray backlighting of annular wire arrays on the Sandia Z-machine using bent-crystal imaging techniques

    International Nuclear Information System (INIS)

    Annular wire array implosions on the Sandia Z-machine can produce >200 TW and 1-2 MJ of soft x rays in the 0.1-10 keV range. The x-ray flux and debris in this environment present significant challenges for radiographic diagnostics. X-ray backlighting diagnostics at 1865 and 6181 eV using spherically-bent crystals have been fielded on the Z-machine, each with a ∼0.6 eVspectral bandpass, 10 (micro)m spatial resolution, and a 4 mm by 20mm field of view. The Z-Beamlet laser, a 2-TW, 2-kJ Nd:glass laser(λ = 527 nm), is used to produce 0.1-1 J x-ray sources for radiography. The design, calibration, and performance of these diagnostics is presented.

  17. 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

  18. 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

  19. 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?...

  20. 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....

  1. 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.

  2. Web 2.0: Where does Europe stand?

    OpenAIRE

    Lindmark, Sven

    2009-01-01

    This report provides a techno-economic analysis of Web 2.0 and an assessment of Europe's position in Web 2.0 applications. Firstly, it introduces the phenomenon of Web 2.0 and its main characteristics: technologies, applications, and user roles. It then provides an overview of its adoption, value chain and business models, before moving to an analysis of its drivers, industrial impact and disruptive potential. Finally, the report assesses the position of the European Web 2.0 applications indu...

  3. Are People Really Social on Porn 2.0?

    OpenAIRE

    Tyson, Gareth; Elkhatib, Yehia; Sastry, Nishanth; Uhlig, Steve

    2015-01-01

    Social Web 2.0 features have become a vital component in a variety of multimedia systems, e.g., Last.fm, Flickr and Spotify. Interestingly, adult video websites are also starting to adopt these Web 2.0 principles, giving rise to the term ``Porn 2.0''. This paper examines a large Porn 2.0 social network, through data covering 563k users. We explore a number of unusual behavioural aspects that set this apart from more traditional multimedia social networks, including differences in browsing act...

  4. 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.

  5. Search of a cyclotron line at 70 keV from Crab Nebula

    International Nuclear Information System (INIS)

    An observation of Crab Nebula was made during a transmediterranean balloon flight launched on August 26, 1979 from Milo Base. The hard x-ray experiment carried a payload consisting of two multiwire proportional counters having a geometric area of 900 cm2 each. A single transit scan of the source was performed on the Crab Nebula region at a float altitude of 2.9 mbs. The preliminary results indicate the existence of an excess flux between 64 - 76 keV above the expected value of Esup(-2.0) power law

  6. A study of the characteristics of the plastic deformation of hydrogen-alloyed VT20 titanium alloy in the temperature range 823-1073 K

    Energy Technology Data Exchange (ETDEWEB)

    Sen' kov, O.N.; Bashkin, I.O.; Malyshev, V.IU.; Poniatovskii, E.G. (Institut Fiziki Tverdogo Tela, Moscow (USSR))

    1990-07-01

    The mechanical behavior of the VT20-hydrogen system was investigated experimentally in the temperature range 823-1073 K at deformation rates of 0.0001-1/s. It is shown that the alloying of VT20 by 0.4-0.58 percent hydrogen reduces the deformation resistance of the alloy by a factor of 1.5-2 at all deformation stages. The effect is particularly pronounced at lower deformation rates. The possible mechanisms controlling the plastic deformation of the alloy are examined. 22 refs.

  7. Variable range hopping in TiO2 insulating layers for oxide electronic devices

    Directory of Open Access Journals (Sweden)

    Y. L. Zhao

    2012-03-01

    Full Text Available TiO2 thin films are of importance in oxide electronics, e.g., Pt/TiO2/Pt for memristors and Co-TiO2/TiO2/Co-TiO2 for spin tunneling devices. When such structures are deposited at a variety of oxygen pressures, how does TiO2 behave as an insulator? We report the discovery of an anomalous resistivity minimum in a TiO2 film at low pressure (not strongly dependent on deposition temperature. Hall measurements rule out band transport and in most of the pressure range the transport is variable range hopping (VRH though below 20 K it was difficult to differentiate between Mott and Efros-Shklovskii's (ES mechanism. Magnetoresistance (MR of the sample with lowest resistivity was positive at low temperature (for VRH but negative above 10 K indicating quantum interference effects.

  8. The dynamic range of LZ

    International Nuclear Information System (INIS)

    The electronics of the LZ experiment, the 7-tonne dark matter detector to be installed at the Sanford Underground Research Facility (SURF), is designed to permit studies of physics where the energies deposited range from 1 keV of nuclear-recoil energy up to 3,000 keV of electron-recoil energy. The system is designed to provide a 70% efficiency for events that produce three photoelectrons in the photomultiplier tubes (PMTs). This corresponds approximately to the lowest energy threshold achievable in multi-tonne time-projection chambers, and drives the noise specifications for the front end. The upper limit of the LZ dynamic range is defined to accommodate the electroluminescence (S2) signals. The low-energy channels of the LZ amplifiers provide the dynamic range required for the tritium and krypton calibrations. The high-energy channels provide the dynamic range required to measure the activated Xe lines

  9. Momentum mapping spectrometer for probing the fragmentation dynamics of molecules induced by keV electrons

    International Nuclear Information System (INIS)

    We describe a new experimental setup for studying the fragmentation dynamics of molecules induced by the impact of keV electrons using the well-known technique of recoil ion momentum spectroscopy. The apparatus consists of mainly a time- and position-sensitive multi-hit particle detector for ion analysis and a channel electron multiplier detector for detecting the ejected electrons. Different components of the setup and the relevant electronics for data acquisition are described in detail with their working principles. In order to verify the reliable performance of the setup, we have recorded the collision-induced ionic spectra of the CO2 molecule by the impact of keV electrons. Information about the ion pairs of CO+:O+, C+:O+ and O+:O+ resulting from dissociative ionizing collisions of 20 and 26 keV electrons with a dilute gaseous target of CO2 molecules has been obtained. Under conditions of the present experiment, the momentum resolutions of the spectrometer for the combined momenta of CO+ and O+ ions in the direction of the time-of-flight axis and perpendicular to the direction of an electron beam are found to be 10.0 ± 0.2 and 15.0 ± 0.3 au, respectively

  10. 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.

  11. W/SiC X-ray multilayers optimized for use above 100 keV

    DEFF Research Database (Denmark)

    Windt, D.L.; Dongey, S.; Hailey, C.J.;

    2002-01-01

    We have developed a new depth-graded multilayer system comprising W and SiC layers, suitable for use as hard X-ray reflective coatings operating in the energy range 100 - 200 keV. Grazing incidence X-ray reflectance at E=8 keV was used to characterize the interface widths, as well as the temporal...

  12. 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.

  13. 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.

  14. 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

  15. 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…

  16. 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...

  17. Students as Digital Citizens on Web 2.0

    Science.gov (United States)

    Nebel, Michelle; Jamison, Barbara; Bennett, Linda

    2009-01-01

    Internet tools associated with Web 2.0 such as wikis, blogs, and video podcasts are increasingly available in elementary classrooms. ("Web 2.0" is a vaguely defined, folk-tech term that means, roughly, the Internet and all software and devices, constantly improving, that strive to exploit it in creative and useful ways.) Today, elementary students…

  18. 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.

  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. Unleashing the Power of Web 2.0

    Science.gov (United States)

    Waters, John K.

    2008-01-01

    As Web 2.0 technologies impact the evolution of online learning, they are certain to blur the definitional lines between electronic portfolios and personal learning environments (PLEs). According to Gary Brown, director of Washington State University's Center for Teaching, Learning, and Technology, the Web 2.0 technologies that are emerging…

  1. 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…

  2. 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.

  3. 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,…

  4. 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…

  5. 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…

  6. 26 CFR 20.7520-2 - Valuation of charitable interests.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Valuation of charitable interests. 20.7520-2... Valuations § 20.7520-2 Valuation of charitable interests. (a) In general—(1) Valuation. Except as otherwise... applicable section 7520 interest rate. If the executor elects the alternate valuation date under section...

  7. 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.

  8. 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.)

  9. 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.

  10. 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.

  11. 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...... 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...

  12. 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.

  13. 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...

  14. The Galactic 511 keV line: analysis and interpretation of Integral observations

    International Nuclear Information System (INIS)

    Ever since the discovery of the 511 keV annihilation line emission from the galactic center region in the late seventies, the origin of galactic positrons has been the topic of a vivid scientific debate. It is also one of the prime scientific objectives of the imaging spectrometer SPI on board ESA's INTEGRAL observatory. In this thesis first a description of the most important SPI sub-system is given - the detector plane. Procedures for detector energy calibration and detector degradation analysis are developed. The determination of instrumental background models, a crucial aspect of data analysis, is elaborated. These background models are then applied to deriving sky maps and spectra of unprecedented quality of the Galactic positron annihilation radiation. The emission is centered on the galactic center with a spatial resolution of 8 degrees (FWHM), a second spatial component appears clearly: the galactic disc. The ray energy has been measured with unprecedented accuracy: 511.0 ± 0.03 keV for a full width at half maximum (FWHM) of 2.07 ± 0.1 keV. The total galactic flux ranges from 1.09 to 2.43 10-3 ph.cm-2.s-1 including uncertainties on spatial distribution. Finally, the implications of these observations for the production of positrons by various Galactic populations are discussed

  15. Scintillation properties of Ba0.20Sr0.80Cl2 single crystal

    International Nuclear Information System (INIS)

    New scintillation crystal of a Ba0.20Sr0.80Cl2 grown by the Czochralski technique is reported. The grown crystal was cut into a size of 10x10x10 mm3. The lattice parameter of the grown crystal is a=b=c=7.041 A and the crystal structure is cubic. The luminescence and scintillation properties of the Ba0.20Sr0.80Cl2 crystal were studied. The luminescent characteristics were measured with ultraviolet (UV) light and X-ray source to study the emission spectra of the crystal. Scintillation properties of the crystal such as pulse height spectra, energy resolution, α/β ratio, light output, proportionality curve, and fluorescence decay time were measured with the various radioactive γ-ray sources and α-source at room temperature. The light output of the crystal was compared with that of the CsI(Tl) crystal and the absolute light output was measured with avalanche photodiode (APD). While the light output of the crystal was less than that of the CsI(Tl), the energy resolution was approximately 6.9% for 137Cs 662 keV γ-ray with PMT which is similar to that of the CsI(Tl) crystal for 137Cs γ-rays. (author)

  16. Basin and Range Province, Western US, USGS Grids #2

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These grid files were used to produce gravity and basin depth maps of the Basin and Range Province, western United States. The maps show gravity values and modeled...

  17. 7.1 keV sterile neutrino constraints from X-ray observations of 33 clusters of galaxies with Chandra ACIS

    Science.gov (United States)

    Hofmann, F.; Sanders, J. S.; Nandra, K.; Clerc, N.; Gaspari, M.

    2016-08-01

    Context. 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 (DM) candidate. Aims: We aim to put 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 DM scenario. Methods: 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. Results: We obtained very detailed spectra around the 3.55 keV range and limits on an unidentified emission line. Assuming all DM were made of 7.1 keV sterile neutrinos, the upper limits on the mixing angle are sin2(2Θ) < 10.1×10-11 from ACIS-I and < 40.3×10-11 from ACIS-S data at 99.7 per cent confidence level. Conclusions: We do not find evidence for an unidentified emission line at 3.55 keV. The sample extends the list of objects searched for an emission line at 3.55 keV and will help to identify the best targets for future studies of the potential DM decay line with upcoming X-ray observatories like Hitomi (Astro-H), eROSITA, and Athena.

  18. 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…

  19. 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…

  20. 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

  1. Electron stopping power and mean free path in organic compounds over the energy range of 20-10,000 eV

    Science.gov (United States)

    Tan, Zhenyu; Xia, Yueyuan; Zhao, Mingwen; Liu, Xiangdong; Li, Feng; Huang, Boda; Ji, Yanju

    2004-07-01

    An empirical method to obtain optical energy loss functions is presented for a large number of organic compounds, for which optical data are not available, on the basis of structure feature analysis of the existed optical energy loss functions for certain organic compounds. The optical energy loss functions obtained by using this method are in good agreement with the experimental data. Based on the Penn's statistical model, a set of systematic expressions have been given for the calculation of the stopping powers and mean free paths of electrons penetrating into the organic compounds in the energy range of E⩽10 keV. Detailed comparison of the calculated data with other theoretical results is presented. The stopping powers and mean free paths for a group of important polymers, without available optical data, have been calculated. In the calculations, three different cases have been considered, i.e. exchange correction not being considered, Ashley exchange correction being involved, and Born-Ochkur exchange correction being included. The results indicate that for these compounds the calculated stopping powers agree well with those obtained by using Bethe-Bloch theory at high-energy limit E=10 keV, as expected for a stopping power theory that should be converged to Bethe-Bloch theory at high energies.

  2. 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.

  3. 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.

  4. Quantum Model for Information Retrieval in Web 2.0

    Directory of Open Access Journals (Sweden)

    Mohammad Bagher Negahban

    2014-06-01

    Full Text Available The study deals with the possibility of information loss in Web 2.0 due to the interaction between the overload and the real information. Using Gottesman and Preskill method, this investigation has proposed a mechanism to calculate the amount of information transformation in Web 2.0. In this proposal, there are three different Hilbert spaces that belong to the degrees of freedom of outside, inside, and overload information of Web 2.0. The information transformation in Web 2.0 is described at two stages. At the first stage, it is shown that the internal stationary state of Web 2.0 can be represented by a maximally entangled two-mode squeezed state of inside and overload information. At the second stage, the state of Web 2.0. is described by a maximally entangled two-mode squeezed state of overload and outside information. The amount of information transformation can be obtained by projecting the state at the first stage on the state at the second stage. Evidently, this study concludes that the information is not lost in Web 2.0.

  5. The Width of the 511 KeV Line from the Bulge of the Galaxy

    CERN Document Server

    Zhitnitsky, A

    2006-01-01

    This is a comment on a recent criticism by Cumberbatch, Silk and Starkman (CSS), astro-ph/0606429. CSS criticize our proposal suggesting that the 511 keV \\gamma rays from the galactic bulge can be naturally explained by the supermassive Compact Composite Objects (CCO) of dark matter. In this comment I present the detail estimations supporting the original claim that the width of the 511 KeV line produced by such a mechanism is very narrow and in a few KeV range for incoming non relativistic electron with typical velocity v_e\\sim 10^{-3}c. The dominant mechanism of the annihilation in this case is the positronium formation e^+e^-\\to ~ ^1S_0 \\to 2\\gamma rather than a direct e^+e^-\\to 2\\gamma annihilation. This is in contrast with analysis of astro-ph/0606429 where a broad MeV distribution is expected as a result of annihilation within CCO framework. I also discuss some general features of the $\\gamma$ rays spectrum (in few MeV region) resulting from the CCO based mechanism.

  6. Optical design of an x-ray absorption spectroscopy beamline at Indus-2 synchrotron radiation source

    International Nuclear Information System (INIS)

    Details of optical design of EXAFS beamline at Indus-2 SRS, under development at CAT, Indore, have been discussed in this report. This beamline will cover the photon energy range of 5 keV to 20 keV and will use a bent crystal of Si(111) having 2d value equal to 6.2709 A. It will accept a horizontal divergence of 1.5 mrad. The heart of the beamline is the bent crystal polychromator which will disperse and focus the synchrotron beam at the experimental sample position. The transmitted radiation from the sample will be, subsequently, detected by a position sensitive detector (CCD type). The detector length is 25 mm. Assuming a suitable value for the distance between the source and the crystal, we have computed several geometrical parameters of the beamline, such as, Bragg angle, crystal length, crystal radius, crystal to sample distance, sample to detector distance, etc. for three different photon energies, namely, 5 keV, 10 keV, and 20 keV. The band passes around these photon energies are 0.3 keV, 1 keV and 2 keV respectively. It has been found that computed geometrical parameters are well within acceptable limits. An extensive ray tracing work was done using the software program SHADOW to evaluate the imaging properties of the beamline. It was established that the image spot size at the sample position improved substantially when the crystal is changed from spherical cylinder shape to elliptic cylinder shape. From the ray intensity plots, the average resolution of the crystal bender was estimated to be 1 eV per channel. Finally based on the optical layout of the beamline, a schematic mechanical layout of the beamline has been prepared. (author)

  7. 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.

  8. r-Java 2.0: the astrophysics

    OpenAIRE

    Kostka, M.; N. Koning; Shand, Z.; Ouyed, R.; Jaikumar, P.

    2014-01-01

    [Context:] This article is the second in a two part series introducing r-Java 2.0, a nucleosynthesis code for open use that performs r-process calculations and provides a suite of other analysis tools. [Aims:] The first paper discussed the nuclear physics inherent to r-Java 2.0 and in this article the astrophysics incorporated into the software will be detailed. [Methods:] R-Java 2.0 allows the user to specify the density and temperature evolution for an r-process simulation. Defining how the...

  9. Adoption of Web 2.0 tools in distance education

    OpenAIRE

    Yasemin Koçak Usluel; Sacide Güzin Mazman

    2009-01-01

    This study has two purposes. First is to explain possible educational utilization of Web 2.0 tools, namely blogs, wikis, podcasts and social networks, from the point of importance of interaction for distance education. The second purpose of this study is to investigate adoption process of Web 2.0 tools in distance education by defining theories and models which have different construct that effect this process. Because the nature and structure of both distance education and Web 2.0 include mu...

  10. 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...

  11. $\\mathbf{\\alpha}$-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.

  12. 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...

  13. 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.

  14. Guidelines for the undergraduate psychology major: Version 2.0.

    Science.gov (United States)

    2016-01-01

    The APA Guidelines for the Undergraduate Psychology Major: Version 2.0 (henceforth Guidelines 2.0; APA, 2013) represents a national effort to describe and develop high-quality undergraduate programs in psychology. The task force charged with the revision of the original guidelines for the undergraduate major examined the success of the document's implementation and made changes to reflect emerging best practices and to integrate psychology's work with benchmarking scholarship in higher education. Guidelines 2.0 abandoned the original distinction drawn between psychology-focused skills and psychology skills that enhance liberal arts development. Instead, Guidelines 2.0 describes five inclusive goals for the undergraduate psychology major and two developmental levels of student learning outcomes. Suggestions for assessment planning are provided for each of the five learning goals. PMID:26866986

  15. 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

  16. 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.

  17. 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.

  18. Informationskompetenz 2.0 und das Verschwinden des Nutzers

    OpenAIRE

    Hapke, Thomas

    2007-01-01

    Ausgehend von einer sich wandelnden Rolle des Nutzers von Informationssystemen im Web 2.0 wird das Konzept Informationskompetenz kritisch hinterfragt. Fünf Thesen zur Informationskompetenz 2.0, verbunden mit Anregungen auf weiterführende Literatur, schlagen einen Perspektivwechsel der in deutschen Bibliotheken vorherrschenden Sicht auf Informationskompetenz hin zu einem ganzheitlicheren Verständnis von Informations- und Lernprozessen vor. Starting from the changing role of the user in info...

  19. Driving Web 2.0 Tool Adoption in Agricultural Education

    OpenAIRE

    Constantina Costopouloul; Maria Ntaliani; Alexander Sideridis

    2013-01-01

    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 tr...

  20. Agriculture, forestry, range, and soils, chapter 2, part C

    Science.gov (United States)

    1975-01-01

    The feasibility of using microwave systems in agriculture, forestry, range, and soil moisture measurements was studied. Theory and preliminary results show the feasibility of measuring moisture status in the soil. For vegetational resources, crop identification for inventory and for yield and production estimates is most feasible. Apart from moisture- and water-related phenomena, microwave systems are also used to record structural and spatial data related to crops and forests.

  1. 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...

  2. Thermodynamic properties of Sm2S3 and SmS2 within wide temperature range

    International Nuclear Information System (INIS)

    For the first time using the mixing method in a wide temperature range inthalpies of Sm2S3 and SmS2 are determined. An intense increase of Sm2S3 enthalpy is observed in the high temperature range and the melting point for this compound is determined. The basic thermodynamic characteristics (enthalpy, thermal capacity, entropy, reduced Gibbs energy) of studied sulfides are calculated

  3. 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.

  4. 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.

  5. 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.

  6. Contribution to the study of nuclear structure using neutron total cross-section measurements between 400 and 1200 keV: isolated resonances and intermediate structure

    International Nuclear Information System (INIS)

    The neutron total cross sections have been measured over the energy range 400 keV - 1200 keV for fluorine, aluminium, silicon, phosphorus, vanadium, chromium, manganese, iron, nickel, cobalt and lead with an energy spread of 3 keV. The neutrons were produced by the T (p,n) 3He reaction, the proton beam was supplied by a 2 MeV Van de Graaff. The structure in 56Fe has been studied in a more detailed way by measuring six angular distributions in the above range and the elastic scattering excitation curves at four angles. The measurements have made it possible to show the existence of the compound nucleus, as well as the presence of an intermediate structure in certain nuclei. (author)

  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 640.2 - Federal law requirements.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Federal law requirements. 640.2 Section 640.2... PROMPTNESS-UNEMPLOYMENT COMPENSATION § 640.2 Federal law requirements. (a) Conformity. Section 303(a)(1) of the Social Security Act, 42 U.S.C. 503(a)(1), requires that a State law include provision for:...

  9. 20 CFR 650.2 - Federal law requirements.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Federal law requirements. 650.2 Section 650.2... PROMPTNESS-UNEMPLOYMENT COMPENSATION § 650.2 Federal law requirements. (a) Section 303(a)(1) of the Social Security Act requires that a State law include provision for: Such methods of administration * * * as...

  10. Performance of a time-of-flight silicon strip telescope in the temperature range 20 C to -55 C

    Energy Technology Data Exchange (ETDEWEB)

    Codino, A. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Brunetti, M.T. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Federico, C. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Grimani, C. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Macchiaiolo, T. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Menichelli, M. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Minelli, G. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Miozza, M. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Plouin, F. [Laboratoire National Saturne, Gif-Sur-Yvette, Saclay (France)

    1995-10-15

    A cold silicon strip telescope for time-of-flight determination operating at -55 C has been tested using a hadron beam at Saturne II, Saclay. We present performance tests of the telescope, the time-of-flight distributions between pairs of silicon hodoscopes and their dependence on temperature. A detailed description of the apparatus, the refrigerator system and the calibration procedures is also reported. A linear relationship between the time resolution and the temperature of the apparatus is measured. An improvement of a factor 2 in the time-of-flight resolution is observed when the temperature decreases from +20 C to -55 C. (orig.).

  11. Performance of a time-of-flight silicon strip telescope in the temperature range 20 C to -55 C

    International Nuclear Information System (INIS)

    A cold silicon strip telescope for time-of-flight determination operating at -55 C has been tested using a hadron beam at Saturne II, Saclay. We present performance tests of the telescope, the time-of-flight distributions between pairs of silicon hodoscopes and their dependence on temperature. A detailed description of the apparatus, the refrigerator system and the calibration procedures is also reported. A linear relationship between the time resolution and the temperature of the apparatus is measured. An improvement of a factor 2 in the time-of-flight resolution is observed when the temperature decreases from +20 C to -55 C. (orig.)

  12. Comparison of Cervical Range of Motion and Cervical FRR between Computer Users in Their Early and Late 20s in Korea

    OpenAIRE

    Yoo, Won-gyu

    2014-01-01

    [Purpose] This study compared the cervical range of motion and cervical FRR between computer users in their early and late 20s in Korea. [Subjects] Eleven male and 7 female computer users in their early 20s and 10 male and 6 female computer users in their late 20s participated in this study. [Methods] All cervical ROM measurements were taken with a Cervical Range of Motion Instrument. Electromyographic (EMG) data were obtained for analyzing the FR ratio. [Results] Cervical extension, right an...

  13. 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.

  14. 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.

  15. 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

  16. Informationskompetenz 2.0 und das Verschwinden des "Nutzers" [Information literacy 2.0 and the disappearance of the user

    OpenAIRE

    Hapke, Thomas

    2007-01-01

    Starting from the changing role of the user in information systems in the Web 2.0 this paper critically questions the concept of information literacy. Five theses on information literacy 2.0 as well as suggestions for further reading offer the possibility to change the perspective of the view on information literacy predominating in German libraries in the direction of a more holistic view of information and learning processes.

  17. 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.

  18. 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.

  19. Low-power 20-meter 3D ranging SPAD camera based on continuous-wave indirect time-of-flight

    Science.gov (United States)

    Bellisai, S.; Ferretti, L.; Villa, F.; Ruggeri, A.; Tisa, S.; Tosi, A.; Zappa, F.

    2012-06-01

    Three dimensional (3D) image acquisitions is the enabling technology of a great number of applications; culture heritage morphology study, industrial robotics, automotive active safety and security access control are example of applications. The most important feature is the high frame-rate, to detect very fast events within the acquired scenes. In order to reduce the computational complexity, Time-of-Flight algorithms for single sensor cameras are used. To achieve high-frame rate and high distance measurement accuracy it is important to collect the most part of the reflected light using sensor with very high sensitivity, allowing the implementation of a low-power light source. We designed and developed a single-photon detection based 3D ranging camera, capable to acquire distance image up to 22.5 m, with a resolution down to one centimeter. The light source used in this prototype employs 8 laser diodes sinusoidally modulated. The imager used in the application is based on Single-Photon Avalanche Diodes (SPADs) fabricated in a standard CMOS 0.35 μm technology. The sensor has 1024 pixels arranged in a 32x32 squared layout, with overall dimensions of 3.5mm x 3.5mm. The camera acquires 3D images through the continuous-wave indirect Time of Flight (cw-iTOF) technique. The typical frame-rate is 20 fps while the theoretical maximum frame-rate is 5 kfps. The precision is better than 5 cm within 22.5 m range, and can be effectively used in indoor applications, e.g. in industrial environment.

  20. 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.

  1. 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.

  2. [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.

  3. 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

  4. The unlubricated reciprocating sliding wear of 316 stainless steel in C02 in the temperature range 20 to 6000C

    International Nuclear Information System (INIS)

    The friction and wear behaviour of 316 stainless steel in C02 has been investigated in the load range 8 - 5ON from 20 to 6000C. Wear transitions occurred at all temperatures but were load dependent. At and below 3000C wear transitions only took place at low leads whereas above 3000C transitions were seen al all loads. The low temperature wear transition, giving an order of magnitude decrease in wear rate was associated with a change in friction behaviour. The friction force across the specimen was initially widely fluctuating and varied from cycle to cycle. After a time, which did not necessarily coincide with the wear transition the cyclic variation in the friction force become much less. This smoother sliding is thought to indicate a trend to oxide -oxide contacts. At higher temperatures wear transitions result in a two orders of magnitude reduction in wear. The corresponding friction transition was similar to the low temperature friction change but also included a marked temporary drop in the coefficient of friction. (author)

  5. 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.

  6. 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.

  7. RSA/Legacy Wind Sensor Comparison. Part 2; Eastern Range

    Science.gov (United States)

    Short, David A.; Wheeler, Mark M.

    2006-01-01

    This report describes a comparison of data from ultrasonic and propeller-and-vane anemometers on 5 wind towers at Kennedy Space Center and Cape Canaveral Air Force Station. The ultrasonic sensors are scheduled to replace the Legacy propeller-and-vane sensors under the Range Standardization and Automation (RSA) program. Because previous studies have noted differences between peak wind speeds reported by mechanical and ultrasonic wind sensors, the latter having no moving parts, the 30th and 45th Weather Squadrons wanted to understand possible differences between the two sensor types. The period-of-record was 13-30 May 2005, A total of 357,626 readings of 1-minute average and peak wind speed/direction from each sensor type were used. Statistics of differences in speed and direction were used to identify 15 out of 19 RSA sensors having the most consistent performance, with respect to the Legacy sensors. RSA average wind speed data from these 15 showed a small positive bias of 0.38 kts. A slightly larger positive bias of 0.94 kts was found in the RSA peak wind speed.

  8. 20 CFR 636.2 - Protection of informants.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Protection of informants. 636.2 Section 636.2 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR COMPLAINTS, INVESTIGATIONS... benefit to which that person is entitled under the provisions of the Act or the regulations because...

  9. 20 CFR 211.2 - Definition of compensation.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Definition of compensation. 211.2 Section 211... CREDITABLE RAILROAD COMPENSATION § 211.2 Definition of compensation. (a) The term compensation means any form... termination allowance paid under section 702 of that Act. Compensation may be paid as money, a commodity,...

  10. Luminescence excitation characteristics of Ca-, Na- and K-aluminosilicates (feldspars), in the stimulation range 20-500 eV: optical detection of XAS

    CERN Document Server

    Poolton, N R J; Quinn, F M; Pantos, E; Andersen, C E; Bøtter-Jensen, L; Johnsen, O; Murray, A S

    2003-01-01

    We demonstrate that the visible/UV luminescence from common feldspar crystals (NaAlSi sub 3 O sub 8 , KAlSi sub 3 O sub 8 and CaAl sub 2 Si sub 2 O sub 8) can be used to detect detailed L-edge and associated near-edge absorption structure of the main constituent atoms (Ca, K, Na, Al, Si), when exciting in the energy range 20-500 eV. Comparisons of the spectral features are drawn with similar measurements made on the associated materials SiO sub 2 , Al sub 2 O sub 3 and CaCO sub 3. The potential for using optically detected x-ray absorption spectroscopy as a method for identifying the luminescent components of mixed mineral samples is considered.

  11. 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.

  12. 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

  13. 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.

  14. 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.

  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. Adoption of Web 2.0 tools in distance education

    Directory of Open Access Journals (Sweden)

    Yasemin Koçak Usluel

    2009-07-01

    Full Text Available This study has two purposes. First is to explain possible educational utilization of Web 2.0 tools, namely blogs, wikis, podcasts and social networks, from the point of importance of interaction for distance education. The second purpose of this study is to investigate adoption process of Web 2.0 tools in distance education by defining theories and models which have different construct that effect this process. Because the nature and structure of both distance education and Web 2.0 include multifaceted and dynamic variables, the limitation of utilization from only single diffusion, adoption or acceptance model or theory is underlined and it is proposed to handle a holistic view or using different models and theories suitable for research variables.

  17. 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.

  18. The photoneutron cross section of 20Ne

    International Nuclear Information System (INIS)

    The photoneutron cross section of 20Ne has been measured over a photon energy range 16 to 29 MeV in steps of 100 keV. The giant dipole resonance is resolved into three strong peaks below 21 MeV and at least two broader resonances at higher excitations. This structure is consistent with earlier measurements of poorer resolution and shows a correlation with the recent calculations of Schmid and Do Dang. Comparisons with high resolution neutron time-of-flight and electron scattering data indicate that there appear to exist in the giant resonance of 20Ne, regions of structure roughly 2-3 MeV wide which exhibit localised characteristics related to the excitation mechanisms. The role of deformation and configuration splitting effects in the cross section are discussed and possible directions of further study are noted which might clarify the situation more fully

  19. Effects of 50 keV and 100 keV Proton Irradiation on GaInP/GaAs/Ge Triple-Junction Solar Cells

    Institute of Scientific and Technical Information of China (English)

    王荣; 冯钊; 刘运宏; 鲁明

    2012-01-01

    GaInP/GaAs/Ge triple-junction solar cells were irradiated with 50 keV and 100 keV protons at fluences of 5 × 10^10 cm^-2, 1 × 10^11 cm^-2,1 × 10^12 cm^-2, and 1 × 10^13 cm^-2. Their performance degradation is analyzed using current-voltage characteristics and spectral response measurements, and then the changes in Isc, Voc, Pmax and the spectral response of the cells are observed as functions of proton irradiation fluence and energy. The results show that the spectral response of the top cell degrades more significantly than that of the middle cell, and 100 keV proton-induced degradation rates of Isc, Voc and Pmax are larger compared with 50 keV proton irradiation.

  20. Mapping ORM 2.0 into OWL 2

    Science.gov (United States)

    Pan, Wen-lin; Liu, Da-xin

    2011-12-01

    ORM (Object Role Modeling) has been used as an ontology modeling language to model domain ontologies. In order to publish domain ontologies modeled in ORM on the Semantic Web, it needs to translate ORM models into OWL 2, the latest standard Web Ontology Language. Several equivalent transformation methods for ORM model have been considered and a series of mapping rules have been presented.

  1. EXAFS STUDY OF THE SHORT RANGE STRUCTURE OF NANOCRYSTALLINE BCC-Fe80Cu20 SOLID SOLUTION

    Institute of Scientific and Technical Information of China (English)

    Y.Z. Yang; X.J. Bai; T.C. Kuang; G.M. Wang; S. Q. Wei

    2002-01-01

    The structure of bcc-Fe80 Cu2o solid solution produced by mechanical alloying of theelemental bcc-Fe and fcc-Cu powders has been studied using X-ray diffraction and theextended X-ray absorption fine structure (EXAFS) techniques. The disappearance ofelemental Fe and Cu X-ray diffraction (XRD) peaks and the presence of bcc structuralXRD peaks illustrate the formation of a nanocrystalline single-phase bcc-Fe80 Gu20solid solution. From the EXAFS results, the clear observation of Cu atoms taking onbcc coordination in the solid solution and Fe atoms remaining bcc structure furtherverifies the reality of atomic alloying between Fe and Cu atoms and the lattice changeof Cu from fcc to bcc. However, the supersaturated bcc solid solution is not chemicallyuniform, i.e., some regions are rich in Fe atoms and other regions rich in Cu atoms.

  2. mHealth 2.0: Experiences, Possibilities, and Perspectives.

    Science.gov (United States)

    Becker, Stefan; Miron-Shatz, Talya; Schumacher, Nikolaus; Krocza, Johann; Diamantidis, Clarissa; Albrecht, Urs-Vito

    2014-01-01

    With more than 1 billion users having access to mobile broadband Internet and a rapidly growing mobile app market, all stakeholders involved have high hopes that this technology may improve health care. Expectations range from overcoming structural barriers to access in low-income countries to more effective, interactive treatment of chronic conditions. Before medical health practice supported by mobile devices ("mHealth") can scale up, a number of challenges need to be adequately addressed. From a psychological perspective, high attrition rates, digital divide of society, and intellectual capabilities of the users are key issues when implementing such technologies. Furthermore, apps addressing behavior change often lack a comprehensive concept, which is essential for an ongoing impact. From a clinical point of view, there is insufficient evidence to allow scaling up of mHealth interventions. In addition, new concepts are required to assess the efficacy and efficiency of interventions. Regarding technology interoperability, open standards and low-energy wireless protocols appear to be vital for successful implementation. There is an ongoing discussion in how far health care-related apps require a conformity assessment and how to best communicate quality standards to consumers. "Apps Peer-Review" and standard reporting via an "App synopsis" appear to be promising approaches to increase transparency for end users. With respect to development, more emphasis must be placed on context analysis to identify what generic functions of mobile information technology best meet the needs of stakeholders involved. Hence, interdisciplinary alliances and collaborative strategies are vital to achieve sustainable growth for "mHealth 2.0," the next generation mobile technology to support patient care. PMID:25099752

  3. UML 2.0 Pocket Reference UML Syntax and Usage

    CERN Document Server

    Pilone, Dan

    2006-01-01

    Globe-trotting travelers have long resorted to handy, pocket-size dictionaries as an aid to communicating across the language barrier. Dan Pilone's UML 2.0 Pocket Reference is just such an aid for on-the-go developers who need to converse in the Unified Modeling Language (UML). Use this book to decipher the many UML diagrams you'll encounter on the path to delivering a modern software system. Updated to cover the very latest in UML, you'll find coverage of the following UML 2.0 diagram types: Class diagramsComponent diagrams*Sequence diagrams*Communication diagrams*Timing diagrams*Interactio

  4. Conceptos y Aplicaciones de la Web 2.0

    OpenAIRE

    C. Naval; Cruz, R.E. (Reyna Esmeralda); S. Lara

    2010-01-01

    La sociedad evoluciona y con ella las formas de comunicación e interacción. Uno de los cambios que está teniendo más impacto social es probablemente el uso de la web y sus aplicaciones actuales, a lo que denominamos Web 2.0. En este capítulo desarrollamos el concepto Web 2.0 siguiendo a O'Reilly, además de algunas de sus aplicaciones. Asimismo, se verán algunos enfoques del futuro de la web y las consecuencias que trae esta nueva forma de comunicación e interacción.

  5. Formación Web 2.0

    OpenAIRE

    Universidad de Salamanca (España). SCOPEO

    2009-01-01

    [ES] Este número inaugural de la serie monográfica del Observatorio de la actividad, la innovación y las tendencias en la Formación en Red, SCOPEO, busca analizar y estimar el valor formativo de las actuales aplicaciones sociales de la Web, caracterizadas bajo el término de Web 2.0, que definen un conjunto de tendencias emergentes sobre las que es necesario repensar los procesos de formación en red. El monográfico contiene tres secciones. La primera, “La Web 2.0 o la evolución social de...

  6. [Adolescents in Web 2.0: risks and chances ].

    Science.gov (United States)

    Salisch, Maria von

    2014-01-01

    That almost all adolescents possess an individual access to the internet and that they use it every day, lays the foundation for the improved means of self presentation and participation that are known by the notion of Web 2.0. Social networks and other interactive internet formats give rise to new risks like cyber mobbing which is the topic of three contributions. At the same time, Web 2.0 offers chances in the form of online counseling and online therapy that cater to the preferences of media-friendly target group of adolescents.

  7. [Adolescents in Web 2.0: risks and chances ].

    Science.gov (United States)

    Salisch, Maria von

    2014-01-01

    That almost all adolescents possess an individual access to the internet and that they use it every day, lays the foundation for the improved means of self presentation and participation that are known by the notion of Web 2.0. Social networks and other interactive internet formats give rise to new risks like cyber mobbing which is the topic of three contributions. At the same time, Web 2.0 offers chances in the form of online counseling and online therapy that cater to the preferences of media-friendly target group of adolescents. PMID:24877775

  8. 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

  9. Heterogeneous computing with OpenCL 2.0

    CERN Document Server

    Kaeli, David R; Schaa, Dana; Zhang, Dong Ping

    2015-01-01

    Heterogeneous Computing with OpenCL 2.0 teaches OpenCL and parallel programming for complex systems that may include a variety of device architectures: multi-core CPUs, GPUs, and fully-integrated Accelerated Processing Units (APUs). This fully-revised edition includes the latest enhancements in OpenCL 2.0 including: Shared virtual memory to increase programming flexibility and reduce data transfers that consume resources Dynamic parallelism which reduces processor load and avoids bottlenecks Improved imaging support and integration with OpenGL  Designed to work on multiple platfor

  10. Biofuels 2.0 move to pilot plant; Les biocarburants 2.0 passent au pilote

    Energy Technology Data Exchange (ETDEWEB)

    Dupin, L

    2010-02-15

    The second generation of biofuels, which use the non-energy parts of plants, do not compete with the food industry. These biofuels have been tried and tested at the laboratory but challenges are occurring with the transition to industrial plants. Demonstrators and prototypes are developing in Germany, Japan, USA and France and bet on two different processes, the biochemical way (enzymatic reaction and fermentation) and the thermochemical way (gasification and Fischer-Tropsch synthesis). Research is in progress on a possible third generation of biofuels which will use micro-algae. The interest of this third way is triple: no competition with the food industry, no land use (production in bioreactors), and enhanced CO{sub 2} capture. (J.S.)

  11. 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.

  12. Scholarship 2.0: analyzing scholars’ use of Web 2.0 tools in research and teaching activity

    Directory of Open Access Journals (Sweden)

    Licia Calvi

    2013-11-01

    Full Text Available Over the past 15 years the Web has transformed the ways in which we search for information and use it. In more recent years, we have seen the emergence of a new array of innovative tools that collectively go under the name of ‘Web 2.0’, in which the information user is also increasingly an information producer (i.e., prosumer, by sharing or creating content.The success of Web 2.0 tools for personal use is only partially replicated in the professional sphere and, particularly, in the academic environment in relation with research and teaching.To date, very few studies have explored the level of adoption of Web 2.0 among academic researchers in their research and teaching activity. It is not known in what way how and how much Web 2.0 is currently used within research communities, and we are not aware of the drivers and the drawbacks of the use of Web 2.0 tools in academia, where the majority of people is focused either on research or on teaching activities.To analyse these issues, i.e. the combined adoption of Web 2.0 tools in teaching and research, the authors carried out a survey among teaching and researching staff of the University of Breda in The Netherlands. This country was chosen mainly because it is on the cutting edge as far as innovation is concerned. An important driver in choosing the Breda University’s academic community was the fact that one of the two authors of this survey works as senior researcher at this university.The purpose of our survey was to explore the level of adoption of Web 2.0 tools among the academic communities. We were interested in investigating how they were using these tools in the creation of scientific knowledge both in their research and teaching activity. We were also interested in analysing differences in the level of adoption of Web 2.0 tools with regard to researchers’ position, age, gender, and research field.Finally, in our study we explored the issue of peer reviewing in the Web 2.0 setting

  13. A 2-Dimensional Micro Flow Sensor with Wide Range Flow Sensing Properties

    Institute of Scientific and Technical Information of China (English)

    Wan-Young Chung; Tae-Yong Kim

    2006-01-01

    A new silicon micro flow sensor with multiple temperature sensing elements was proposed and numerically simulated in considering wide range flow measuring properties. The micro flow sensor has three pairs of temperature sensing elements with a central heater compared with typical sensor which has only a temperature sensing element on each side of a central heater. A numerical analysis of the micro flow sensor by Finite Difference Formulation for Heat Transfer Equation was performed. The nearest pair of temperature sensor showed very good linear sensitivity between 0 to 0.4 m/s flow and saturated from 0.75 m/s flow. However the furthest pair of temperature sensor showed some flow sensitivity even though the flow rate of 2.0 m/s. Thus, this suggested new micro flow meter with multiple temperature sensing elements could be used as a thermal mass flow sensor which has accuracy sensitivity for very wide flow range.

  14. Search for a 17 keV neutrino in the internal bremsstrahlung spectrum of 125I

    International Nuclear Information System (INIS)

    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 1.2x106 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 Suric 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

  15. Design of the experimental apparatus to obtain a thermal neutron beam, intermediate-energy neutrons (2-144 keV) and high-energy photons (6 MeV) by means of the TRIGA reactor at the ENEA Casaccia center

    CERN Document Server

    Laitano, R F

    1987-01-01

    Design of the experimental apparatus to obtain a thermal neutron beam, intermediate-energy neutrons (2-144 keV) and high-energy photons (6 MeV) by means of the TRIGA reactor at the ENEA Casaccia center

  16. TERS v2.0: An improved version of TERS

    Science.gov (United States)

    Nath, S.

    2009-11-01

    We present a new version of the semimicroscopic Monte Carlo code "TERS". The procedure for calculating multiple small angle Coulomb scattering of the residues in the target has been modified. Target-backing and residue charge-reset foils, which are often used in heavy ion-induced complete fusion reactions, are included in the code. New version program summaryProgram title: TERS v2.0 Catalogue identifier: AEBD_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEBD_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 7309 No. of bytes in distributed program, including test data, etc.: 1 219 555 Distribution format: tar.gz Programming language: C Computer: The code has been developed and tested on a PC with Intel Pentium IV processor. Operating system: Linux RAM: About 8 Mbytes Classification: 17.7 External routines: pgplot graphics subroutine library [1] should be installed in the system for generating residue trajectory plots. (The library is included in the CPC distribution file.) Catalogue identifier of previous version: AEBD_v1_0 Journal reference of previous version: Comput. Phys. Comm. 179 (2008) 492 Does the new version supersede the previous version?: Yes Nature of problem: Recoil separators are employed to select and identify nuclei of interest, produced in a nuclear reaction, rejecting unreacted beam and other undesired reaction products. It is important to know what fraction of the selected nuclei, leaving the target, reach the detection system. This information is crucial for determining absolute cross section of the studied reaction. Solution method: Interaction of projectiles with target nuclei is treated event by event, semimicro-scopically. Position and angle (with respect to beam direction), energy and charge state of the reaction products are

  17. 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.

  18. 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. PMID:27548518

  19. Data-Based Decision Making 2.0

    Science.gov (United States)

    Protheroe, Nancy

    2011-01-01

    The phrase "data-based decision making" has been used so often in discussions about school improvement efforts that it has become almost a mantra. However, it's "how" data is used that really provides the critical link between practice and school improvement. "Data-Based Decision Making 2.0" is designed to help principals take on the role of…

  20. Implications of Implementing Web 2.0 on Education

    Science.gov (United States)

    Valerio, Gabriel; Valenzuela, Ricardo

    2013-01-01

    The Knowledge Society has altered the way humanity works, learns and amuses itself; from here the rise of the so called e-learning, an educational modality whose "innovation" has been questioned because of the tendency to simulate traditional ways to educate. This paper explores the concept of e-learning 2.0, the implications of…

  1. Experience of Integrating Web 2.0 Technologies

    Science.gov (United States)

    Zdravkova, Katerina; Ivanovic, Mirjana; Putnik, Zoran

    2012-01-01

    Web users in the 21st century are no longer only passive consumers. On a contrary, they are active contributors willing to obtain, share and evolve information. In this paper we report our experience regarding the implementation of Web 2.0 concept in several Computer Ethics related courses jointly conducted at two Universities. These courses have…

  2. Web 2.0 and gaming in libraries

    CERN Document Server

    McNicol, Sarah

    2009-01-01

    More and more libraries from all sectors are beginning to embrace Web 2.0 technologies and to investigate the potential of social networking, blogs, podcasting, wikis, gaming and other tools to connect with younger members of their user community in particular. This e-book reports on some of the most recent developments and activities in this dynamic, and often controversial, area.

  3. Collaborative learning through advanced Web2.0 practices

    DEFF Research Database (Denmark)

    Tambouris, Efthimios; Panopoulou, Eleni; Tarabanis, Konstantinos;

    2010-01-01

    Latest advances in ICT have started impacting also the field of education and training. Social computing and Web2.0 technologies have brought vigorous opportunities for learning and have realised a shift of the web‟s role in learning from an information carrier to a facilitator for the creation...

  4. Darwin core based data streamlining with digimus 2.0

    Digital Repository Service at National Institute of Oceanography (India)

    Kakodkar, A.P.; Kerkar, S.S.; Varghese, N.S.; Kavlekar, D.P.; Achuthankutty, C.T.

    data according to current data standards and without spending more time in developing software tools for data management or learning web programming. As a web based tool DigiMus 2.0, does not require specific hardware or software other than a...

  5. Web 2.0: Hypertext by Any Other Name?

    OpenAIRE

    Millard, David; Ross, Martin, 1862-1915

    2006-01-01

    Web 2.0 is the popular name of a new generation of Web applications, sites and companies that emphasis openness, community and interaction. Examples include technologies such as Blogs and Wikis, and sites such as Flickr. In this paper we compare these next generation tools to the aspirations of the early Hypertext pioneers to see if their aims have finally been realized.

  6. 20 CFR 336.2 - Duration of normal unemployment benefits.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Duration of normal unemployment benefits. 336... UNEMPLOYMENT INSURANCE ACT DURATION OF NORMAL AND EXTENDED BENEFITS Normal Benefits § 336.2 Duration of normal unemployment benefits. (a) 130 compensable day limitation. A qualified employee who has satisfied the...

  7. Towards adaptation in e-learning 2.0

    Science.gov (United States)

    Cristea, Alexandra I.; Ghali, Fawaz

    2011-04-01

    This paper presents several essential steps from an overall study on shaping new ways of learning and teaching, by using the synergetic merger of three different fields: Web 2.0, e-learning and adaptation (in particular, personalisation to the learner). These novel teaching and learning ways-the latter focus of this paper-are reflected in and finally adding to various versions of the My Online Teacher 2.0 adaptive system. In particular, this paper focuses on a study of how to more effectively use and combine the recommendation of peers and content adaptation to enhance the learning outcome in e-learning systems based on Web 2.0. In order to better isolate and examine the effects of peer recommendation and adaptive content presentation, we designed experiments inspecting collaboration between individuals based on recommendation of peers who have greater knowledge, and compare this to adaptive content recommendation, as well as to "simple" learning in a system with a minimum of Web 2.0 support. Overall, the results of adding peer recommendation and adaptive content presentation were encouraging, and are further discussed in detail in this paper.

  8. Assessing E-Learning 2.0 System Success

    Science.gov (United States)

    Wang, Hei Chia; Chiu, Yi Fang

    2011-01-01

    Traditional e-learning systems support "one-way" communication. Teachers provide knowledge for learners, but they are unable to use a student's learning experiences to benefit the class as a whole. To address these problems, this study explores e-learning success factors via the design and evaluation of an e-learning 2.0 system. This study…

  9. Leisure Commons: Spatial History of Web 2.0

    NARCIS (Netherlands)

    P.A. Arora (Payal)

    2014-01-01

    markdownabstract__Abstract__ The Internet has matured. It is now characterized by a new generation of websites popularly termed as Web 2.0. The nature of this transformation is predominantly social versus technical in nature, and is marked by the rise of social network sites and user generated cont

  10. Marketing 2.0: La nueva forma de hacer marketing.

    OpenAIRE

    Morón Redondo, Ana

    2014-01-01

    La web 2.0 ha revolucionado el concepto de marketing empresarial, dando lugar a una nueva corriente de colaboración y comunicación multidireccional on-line empresa-usuario a través de Internet y de las redes sociales.

  11. Tweeting and Blogging: Moving towards Education 2.0

    Science.gov (United States)

    Luo, Tian; Franklin, Teresa

    2015-01-01

    This paper reports on an exploratory study that employed Twitter and blogs as instructional Web 2.0 tools to support student learning in an undergraduate-level class. Case study methodology entailing a usage survey, an exit survey, and 12 in-depth semi-structured interviews was sought to examine patterns and characteristics of students' usage of…

  12. r-Java 2.0: the astrophysics

    CERN Document Server

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

    2014-01-01

    [Context:] This article is the second in a two part series introducing r-Java 2.0, a nucleosynthesis code for open use that performs r-process calculations and provides a suite of other analysis tools. [Aims:] The first paper discussed the nuclear physics inherent to r-Java 2.0 and in this article the astrophysics incorporated into the software will be detailed. [Methods:] R-Java 2.0 allows the user to specify the density and temperature evolution for an r-process simulation. Defining how the physical parameters (temperature and density) evolve can effectively simulate the astrophysical conditions for the r-process. Within r-Java 2.0 the user has the option to select astrophysical environments which have unique sets of input parameters available for the user to adjust. In this work we study three proposed r-process sites; neutrino-driven winds around a proto-neutron star, ejecta from a neutron star merger and ejecta from a quark nova. The underlying physics that define the temperature and density evolution fo...

  13. A Innovative Engineering Summer School V2.0

    DEFF Research Database (Denmark)

    Bennedsen, Jens; Larsen, Peter Gorm

    2010-01-01

    This article describes a summer school which focuses on a conceive-design project. The summer school has been run three times; each of the implementations is described. The last implementation (v2.0) is discussed and four challenges are identified and discussed in detail: assignments, the role of...

  14. Changing Academic Teaching with Web 2.0 Technologies

    Science.gov (United States)

    Newland, Barbara; Byles, Linda

    2014-01-01

    Academic teaching can change with the use of Web 2.0 technologies, such as blogs and wikis, as these enable a different pedagogical approach through collaborative learning and the social construction of knowledge. Student expectations of their university learning experience have changed as they expect e-learning to be part of the learning…

  15. Web 2.0 Tools for Supporting Teaching

    Science.gov (United States)

    Konstantinidis, Angelos; Theodostadou, Dimitra; Pappos, Christos

    2013-01-01

    Web 2.0 tools provide enormous opportunities for teaching and learning, yet their application in education is still underdeveloped. What is more, it is no longer possible for teachers to ignore such a technological advance, while they are expected to provide students with opportunities to take control of their learning. However, teachers are still…

  16. Social Dimension of Web 2.0 in Engineering Education

    Science.gov (United States)

    Ahrens, Andreas; Zascerinska, Jelena

    2010-01-01

    Contemporary engineers need to become more cognizant and more responsive to the emerging needs of the market for engineering and technology services. Social dimension of Web 2.0 which penetrates our society more thoroughly with the availability of broadband services has the potential to contribute decisively to the sustainable development of…

  17. Integrating Web 2.0 across the Curriculum

    Science.gov (United States)

    Oliver, Kevin

    2010-01-01

    For many years, educators have touted the benefits of learning with educational tools such as spreadsheets and databases that allow students to actively process and manipulate information (Jonassen, 1995). Hundreds if not thousands of Web 2.0 tools have been created in the last few years, taking the "technology as tool" metaphor to a new level. In…

  18. From web 2.0 to learning games

    DEFF Research Database (Denmark)

    Duus Henriksen, Thomas

    2011-01-01

    a game-based learning process that made active use of the participants’ current knowledge, both on leadership and on the context they were to lead. The solution developed for doing so was based on some of the ideas from web 2.0, by which the web-page or game merely provides a structure that allows...

  19. Web 2.0 Technologies: Applications for Community Colleges

    Science.gov (United States)

    Bajt, Susanne K.

    2011-01-01

    The current generation of new students, referred to as the Millennial Generation, brings a new set of challenges to the community college. The influx of these technologically sophisticated students, who interact through the social phenomenon of Web 2.0 technology, bring expectations that may reshape institutions of higher learning. This chapter…

  20. Re-Designing Open Data 2.0

    Directory of Open Access Journals (Sweden)

    Alon Peled

    2013-12-01

    Full Text Available Since 2009, eighty-one countries subscribed to President Obama’s Open Government program including its dominant Open Data (OD component. Do Open Data 2.0 plans address the problems detected during the first generation of this program (2010-2012? If not, how can these plans be improved? The article is a review of the main lines of criticism of the original OD program based on lessons learned worldwide. OD1.0 suffered from bad design, flawed execution, and adverse consequences. Open Data 2.0 plans fail to address the critical flaws of the first Open Data program. The analysis of OD1.0 reveals two primary lessons for converting OD2.0 into a more focused and effective openness program: OD2.0 architects must consider agencies’ data release strategies, and avoid creating a transparency “policy bubble”. Numerous countries followed the path of the original American Open Data program; therefore, the future of this program will have an impact on bureaucracies worldwide.

  1. Do you know the way to ... Web 2.0

    NARCIS (Netherlands)

    Kirschner, Paul A.; Wopereis, Iwan

    2013-01-01

    Kirschner, P. A., & Wopereis, I. G. J. H. (2013). Do you know the way to ... Web 2.0? In J. M. Spector, B. B. Lockee, S. E. Smaldino, & M. C. Herring (Eds.), Learning, problem solving, and mindtools: Essays in honor of David H. Jonassen (pp. 88-104). New York, NY: Routledge.

  2. What Web 2.0 Means for Teachers

    Science.gov (United States)

    Criswell, Chad

    2008-01-01

    The term "Web 2.0"--a buzzword for a technological evolution that's been taking place online for some time--has many different definitions. In general, it refers to Web sites that go beyond simply presenting words and images, often allowing users to share information and collaborate in new ways. Content on the Web used to be largely static. One…

  3. Hydroxyapatite-titanium interface reaction induced by keV electron irradiation

    Science.gov (United States)

    Torrisi, L.; Foti, G.

    1992-03-01

    Thin films of hydroxyapatite bioceramic, 5-50 Å in thickness, have been deposited on ion cleaned titanium surfaces to study the chemical-physical adhesion of metal-ceramic interfaces of biomedical devices (orthopaedic and dentistry prosthesis). Film deposition was performed in ultrahigh vacuum condition (10 -10 mbar) using 5 keV argon sputtering of hydroxyapatite matrix; the film thickness was measured in situ with Auger electron spectroscopy. The hydroxyapatite-titanium interface was irradiated with an electron beam of 0.5-5 keV energy and 0.2-2 A/cm 2 current density. During electron irradiation, Auger spectra show chemical shifts of phosphorus, titanium and oxygen peaks. The released electron energy induces modifications in the tetraedric phosphorus-oxygen groups with production of new chemical bonds between phosphorus, oxygen and titanium. Oxygen, for example, diffuses into the titanium interface forming titanium oxide. Chemical reactions induced by electron irradiation are driven by the metal-ceramic interface. Near the interface a strong and fast effect is observed while far from the interface a weak and slow effect occurs. Chemical reactions depend on the electron irradiation dose showing an inhibition threshold at about 10 19 e/cm 2 and, near the interface, a saturation condition at about 5 × 10 20 e/cm 2. Titanium-ceramic chemical reactions are inhibited if the substrate titanium surface is rich in oxide.

  4. Purification, crystallization and preliminary X-ray diffraction analysis of the IL-20-IL-20R1-IL-20R2 complex

    Energy Technology Data Exchange (ETDEWEB)

    Logsdon, Naomi J.; Allen, Christopher E.; Rajashankar, Kanagalaghatta R.; Walter, Mark R. (Cornell); (UAB)

    2012-02-08

    Interleukin-20 (IL-20) is an IL-10-family cytokine that regulates innate and adaptive immunity in skin and other tissues. In addition to protecting the host from various external pathogens, dysregulated IL-20 signaling has been shown to contribute to the pathogenesis of human psoriasis. IL-20 signals through two cell-surface receptor heterodimers, IL-20R1-IL-20R2 and IL-22R1-IL-20R2. In this report, crystals of the IL-20-IL-20R1-IL-20R2 ternary complex have been grown from polyethylene glycol solutions. The crystals belonged to space group P4{sub 1}2{sub 1}2 or P4{sub 3}2{sub 1}2, with unit-cell parameters a = 111, c = 135 {angstrom}, and diffracted X-rays to 3 {angstrom} resolution. The crystallographic asymmetric unit contains one IL-20-IL-20R1-IL-20R2 complex, corresponding to a solvent content of approximately 54%.

  5. A New Observation of the Quiet Sun Soft X-ray (0.5-5 keV) Spectrum

    Science.gov (United States)

    Caspi, A.; Woods, T. N.; Stone, J.

    2012-12-01

    The solar corona is the brightest source of X-rays in the solar system, and the X-ray emission is highly variable with solar activity. While this is particularly true during solar flares, when emission can be enhanced by many orders of magnitude up to gamma-ray energies, even the so-called "quiet Sun" is bright in soft X-rays (SXRs), as the ~1-2 MK ambient plasma of the corona emits significant thermal bremsstrahlung up to ~5 keV. However, the actual solar SXR (0.5-5 keV) spectrum is not well known, particularly during quiet periods, as, with few exceptions, this energy range has not been systematically studied in many years. Previous observations include ultra-high-resolution but very narrow-band spectra from crystral spectrometers (e.g. Yohkoh/BCS), or integrated broadband irradiances from photometers (e.g. GOES/XRS, TIMED/XPS, etc.) that lack detailed spectral information. In recent years, broadband measurements with fair energy resolution (~0.5-0.7 keV FWHM) were made by SphinX on CORONAS-Photon and XRS on MESSENGER, although they did not extend below ~1 keV. We present observations of the quiet Sun SXR emission obtained using a new SXR spectrometer flown on the third SDO/EVE underflight calibration rocket (NASA 36.286). The commercial off-the-shelf Amptek X123 silicon drift detector, with an 8-micron Be window and custom aperture, measured the solar SXR emission from ~0.5 to >10 keV with ~0.15 keV FWHM resolution (though, due to hardware limitations, with only ~0.12 keV binning) and 2-sec cadence over ~5 minutes on 23 June 2012. Despite the rising solar cycle, activity on 23 June 2012 was abnormally low, with no visible active regions and GOES XRS emission near 2010 levels; we measured no solar counts above ~4 keV during the observation period. We compare our X123 measurements with spectra and broadband irradiances from other instruments, including the SphinX observations during the deep solar minimum of 2009, and with upper limits of >3 keV quiet Sun emission

  6. 6p-2h core excitations in 20O

    International Nuclear Information System (INIS)

    The effects of intruder states arising from general positive deformations on the excitation energies, the two-neutron transfer spectroscopic amplitudes for the reaction 18O(t,p)20O, and some electric quadrupole transition amplitudes between some low-lying positive parity states in 20O are presented. The Hamiltonian matrix elements that reproduce experimental data best are also presented along with a general comparison of the results with experiment and with pure (sd)4 shell model results. (author). 19 refs, 2 figs, 5 tabs

  7. Removal of formaldehyde by a pulsed dielectric barrier discharge in dry air in the 20 °C to 300 °C temperature range

    Science.gov (United States)

    Blin-Simiand, N.; Pasquiers, S.; Magne, L.

    2016-05-01

    The influence of the gas mixture temperature, from 20 °C up to 300 °C, on the removal of formaldehyde, diluted at low concentration (less than 800 ppm) in dry air at atmospheric pressure, by a pulsed dielectric barrier discharge (DBD) is studied by means of Fourier transform infrared spectroscopy and micro gas chromatography. Efficient removal of CH2O is obtained and it is found that the characteristic energy, less than 200 J l-1, is a decreasing function of the temperature over the whole range of concentration values under consideration. Byproducts issued from the removal are identified and quantified (CO, CO2, HCOOH, HNO3). Experimental results are analysed using a zero-dimensional simplified DBD-reactor model in order to gain insights on the chemical processes involved. It is shown that the dissociation of the molecule competes with oxidation reactions at low temperature, whereas at high temperature oxidation processes dominate.

  8. 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.

  9. The Open Ed Tech: Never Mind the Edupunks; or, The Great Web 2.0 Swindle

    Science.gov (United States)

    Lamb, Brian; Groom, Jim

    2010-01-01

    Has the wave of the open web crested? What does "open educational technology" look like, and does it stand for anything? In this article, the authors discuss the rise of open educational technology. The present range of Web 2.0 service providers offers a self-evident strategic technology framework. Without much effort, online teachers and learners…

  10. SUC-CORE: SUC 2.0 Annotated with NP Coreference

    OpenAIRE

    Nilsson Björkenstam, Kristina; Byström, Emil

    2012-01-01

    SUC-CORE is a subset of Stockholm Umeå Corpus 2.0 and Swedish Treebank, annotated with noun phrase coreference. While most coreference annotated corpora consist of texts of similar types within related domains, SUC-CORE consists of both informative and imaginative prose and covers a wide range of literary genres and domains.

  11. Mass attenuation coefficients of soil and sediment samples using gamma energies from 46.5 to 1332 keV

    International Nuclear Information System (INIS)

    Mass attenuation coefficients of various soil and sediment samples (density range between 1.0 and 1.7 g cm−3) collected from 60 sites distributed in Syrian land have been determined for gamma lines of 46.5, 59.5, 88, 122, 165, 392, 661, 1173, and 1332 keV using gamma spectrometry and simulation software program X-com. The average mass attenuation coefficients for the studied samples were found to be 0.513, 0.316, 0.195, 0.155, 0.134, 0.096, 0.077, 0.058, and 0.055 cm2 g−1 at previous energies, respectively. The results have shown that Ca and Fe contents of the samples have strong effect on the mass attenuation coefficient at lower energies. In addition, self-attenuation correction factors determined using mass attenuation coefficient was in good agreement with addition spiked reference material method provided that the sample thickness is 2.7 cm. However, mass attenuation coefficients determined in this study can be used for determination of gamma emitters at energy ranges from 46.5 to 1332 keV in any soil and sediment samples having density of 1.0–1.7 g cm−3. - Highlights: ► Mass attenuation coefficients of various soil and sediment samples have been determined for several gamma lines. ► Mass attenuation coefficients for all types of soil and sediment samples for energy range higher than 165 keV, are similar. ► Fe and Ca in samples have a strong effect on mass attenuation coefficient for energies less than 165 keV.

  12. 17-keV neutrino, MSW mechanism, and supernova constraints

    Science.gov (United States)

    Babu, K. S.; Mohapatra, Rabindra N.; Rothstein, I. Z.

    1992-01-01

    A simple form for the neutrino mass matrix describing νe, νμ, ντ, and a sterile state νs is proposed which accommodates the 17-keV neutrino as a νμ-ντ pseudo Dirac pair and simultaneously resolves the solar-neutrino puzzle via νe-νs Mikheyev-Smirnov-Wolfenstein (MSW) oscillation. This model, which is a specific realization of a scheme proposed recently by Caldwell and Langacker, is automatically free of all supernova constraints. It is shown that the mass matrix follows in a technically natural manner in extensions of the standard model with spontaneously broken global U(1)Le-Lμ×U(1)Lτ symmetry. The 17-keV neutrino decays to νe and a Majoron with a lifetime of order 10-1-10-2 sec thus satisfying all cosmological and astrophysical constraints.

  13. Use of Web 2.0 tools by hospital pharmacists.

    Science.gov (United States)

    Bonaga Serrano, B; Aldaz Francés, R; Garrigues Sebastiá, M R; Hernández San Salvador, M

    2014-04-01

    Objetivo: Las herramientas de la Web 2.0 están transformando los canales que los profesionales sanitarios emplean para comunicarse entre sí y con los pacientes por lo que esta situación obliga a un cambio de mentalidad para implementarlas. El objetivo de este estudio fue evaluar el grado de conocimiento y aplicación de las principales herramientas Web 2.0 por parte de farmacéuticos hospitalarios. Método: El estudio se llevó a cabo mediante una encuesta anómina dirigida a todos los miembros de la Sociedad Española de Farmacia Hospitalaria (SEFH) a través de la aplicación Google Drive®. Después de completarse los 3 meses del período de estudio, los datos recogidos se analizaron usando SPPS v15.0. Resultados: La tasa de respuesta fue del 7,3%, siendo el 70,5% mujeres y el 76,3 % especialistas. La mayoría de los que respondieron (54,2%) estaban en el rango de edad de 20 a 35 años. Pubmed fue el medio principal de acceder a los artículos publicados. El 65,2% de los farmacéuticos conocía el término “Web 2.0”. El 45,3% eran usuarios de Twitter, de los cuales un 58,9% principalmente para uso profesional. La mayoría creía que Twitter era una buena herramienta para interactuar entre los profesionales y los pacientes. El 78,7% no usaba un agregador, pero cuando lo hacían, Google Reader era el más habitual. Conclusión: Aunque las aplicaciones de la Web 2.0 están ganando popularidad, algunos profesionales sanitarios se resisten a utilizarlas. De hecho, más de la mitad de los farmacéuticos entrevistados manifestaba un nulo conocimiento de las herramientas de la Web 2.0. Sería positivo que los farmacéuticos las usasen adecuadamente durante su práctica profesional para sacarles el máximo partido.

  14. Preparing Teachers to Integrate Web 2.0 in School Practice: Toward a Framework for Pedagogy 2.0

    Science.gov (United States)

    Jimoyiannis, Athanassios; Tsiotakis, Panagiotis; Roussinos, Dimitrios; Siorenta, Anastasia

    2013-01-01

    Web 2.0 has captured the interest and the imagination of both educators and researchers while it is expected to exert a significant impact on instruction and learning, in the context of the 21st century education. Hailed as an open collaborative learning space, many questions remain unanswered regarding the appropriate teacher preparation and the…

  15. Has Web 2.0 Revitalized Informal Learning? The Relationship between Web 2.0 and Informal Learning

    Science.gov (United States)

    Song, D.; Lee, J.

    2014-01-01

    Learning is becoming increasingly self-directed and often occurs away from schools and other formal educational settings. The development of a myriad of new technologies for learning has enabled people to learn anywhere and anytime. Web 2.0 technology allows researchers to shed a new light on the importance and prevalence of informal learning.…

  16. X-, γ, β-ray detector windows of composite material replacing beryllium in the 4.2-420 K temperature range

    Science.gov (United States)

    Rimbert, J. N.; Testard, O. A.

    1986-10-01

    A new multilayer composite material has been elaborated to produce windows with a good vacuum tightness and high nuclear radiation transmission. This material can advantageously substitute beryllium, because of the difficulties associated with the fabrication of thin laminated beryllium windows without chemical impurities, because of the lack of resistance to atmospheric corrosion and the high cost of these windows. The composite windows are made of thin high purity aluminium barriers (0.15-0.56 μm total thickness) interleaved in structural polyimid films (down to 56 μm total thickness). Its main physical properties are: yield stress (1.2×10 8 Pa), temperature range ( 1ˇK to 420 K) . helium gas porosity (10 -3 cm 3(STP) m -2 atm -1 d -1), optically opaque. The X or γ-ray transmission performance tests have been compared with those for beryllium. They show that the standard multi-interlaminar barrier (MIB) material of 168 μm thickness is equivalent to 500 μm Be for energies lower than 10 keV and to 200 μm Be for energies higher than 100 keV. The windows thus developed have a modular aspect and adapt themselves to various specifications (cryostats, scintillation detectors, semiconductor detectors, X-ray proportional counters, etc.).

  17. A genetically encoded sensor for H2O2 with expanded dynamic range.

    Science.gov (United States)

    Markvicheva, Kseniya N; Bilan, Dmitry S; Mishina, Natalia M; Gorokhovatsky, Andrey Yu; Vinokurov, Leonid M; Lukyanov, Sergey; Belousov, Vsevolod V

    2011-02-01

    Hydrogen peroxide is an important second messenger controlling intracellular signaling cascades by selective oxidation of redox active thiolates in proteins. Changes in intracellular [H(2)O(2)] can be tracked in real time using HyPer, a ratiometric genetically encoded fluorescent probe. Although HyPer is sensitive and selective for H(2)O(2) due to the properties of its sensing domain derived from the Escherichia coli OxyR protein, many applications may benefit from an improvement of the indicator's dynamic range. We here report HyPer-2, a probe that fills this demand. Upon saturating [H(2)O(2)] exposure, HyPer-2 undergoes an up to sixfold increase of the ratio F500/F420 versus a threefold change in HyPer. HyPer-2 was generated by a single point mutation A406V from HyPer corresponding to A233V in wtOxyR. This mutation was previously shown to destabilize interface between monomers in OxyR dimers. However, in HyPer-2, the A233V mutation stabilizes the dimer and expands the dynamic range of the probe.

  18. RHESSI Observations of the Solar Flare Iron-line Feature at 6.7 keV

    OpenAIRE

    Phillips, K. J. H.; Chifor, C.; Dennis, B. R.

    2006-01-01

    Analysis of RHESSI 3--10 keV spectra for 27 solar flares is reported. This energy range includes thermal free--free and free--bound continuum and two line features, at 6.7keV and 8keV, principally due to highly ionized iron (Fe). We used the continuum and the flux in the so-called Fe-line feature at 6.7keV to derive the electron temperature T_e, the emission measure, and the Fe-line equivalent width as functions of time in each flare. The Fe/H abundance ratio in each flare is derived from the...

  19. Effect of strain rate on the hydrogen plastification effect in VT20 titanium alloy in the temperature range of 500-800 C

    Energy Technology Data Exchange (ETDEWEB)

    Bashkin, I.O.; Poniatovskii, E.G.; Sen' kov, O.N.; Malyshev, V.IU. (Institut Fiziki Tverdogo Tela, Moscow (USSR))

    1990-02-01

    The plasticity characteristics of TB20-hydrogen alloys with 0, 0.40 and 0.58 percent (in volume) hydrogen content in the temperature range of 500-800 C and at the shear rate of 0.0001-1/s, are examined. The hydrogen addition to the TB20 alloy leads to a plasticity increase, especially appreciable at epsilon greater than or equal to 0.01/s in the temperature range of 600-720 C (20-45 times). With an increase in temperature and/or a decrease in the strain rate, the TB20 limit deformation increases monotonically, and the limit deformations of the TB20-hydrogen alloys pass through maxima. The alloy plasticity increase correlates with the appearance of softening and steady flow phases at the low stress level, with grain size reduction, and with an increase in deformation homogeneity. 18 refs.

  20. Overview of Emerging Web 2.0-Based Business Models and Web 2.0 Applications in Businesses: An Ecological Perspective

    OpenAIRE

    In Lee

    2011-01-01

    Web 2.0 offers business organizations an array of new ways to interact with customers and partners. Web 2.0 is continuously evolving and offers new business models and support business processes, customer relationship management, and partner relationship management. This study reviews some of the major business applications of Web 2.0, and identifies Web 2.0-based business models. Six emerging Web 2.0-based business models were identified: (1) Broad Online Community, (2) Focused Online Commun...