Sample records for 2 20 kev range

  1. A direct comparison of Ge and Si(Li) detectors in the 2--20 keV range

    SciTech Connect

    Rossington, C.S.; Giauque, R.D.; Jaklevic, J.M.

    1991-10-01

    The spectral response of high purity Ge (HPGe) and lithium-drifted Si (Si(Li)) surface barrier detectors of similar geometry has been measured over a range of x-ray energies under identical experimental conditions. Detector characteristics such as spectral background, escape peak intensity, entrance window absorption, and energy resolution are presented and compared. Although these characteristic have been discussed in the literature previously, this paper represents an attempt to consolidate the information by making comparisons under equivalent experimental conditions for the two types of detectors. A primary goal of the study is a comparison of the two types of detectors for use in x-ray fluorescence applications.

  2. Quiet-time Interplanetary ˜2-20keV Superhalo Electrons at Solar Minimum

    NASA Astrophysics Data System (ADS)

    Wang, L.; Lin, R. P.; Salem, C. S.; Pulupa, M.

    2011-12-01

    The average flux of the ~2-20 keV superhalo electrons in the solar wind during quiet-time periods, measured by the Suprathermal Electron instrument onboard the two STEREO spacecraft, slowly decreases with time from 2007 to 2009 and then increases in 2010, similar to the solar cycle variation around this solar minimum. We made a comprehensive study for a 2-year period from 2007 March through 2009 March, and found that the observed quiet-time ˜2-20 keV superhalo electrons have a nearly isotropic angular distribution and a power-law spectrum, f ˜ v-?, ranging from v-5 to v-8.7, with the average index of 6.69. The observed power-law spectrum varies significantly on spatial scales of >˜0.1 AU and/or temporal scale of >˜ days. There is no correlation (-0.1 < coefficient < 0.2) with the solar wind proton density, velocity and temperature, but the power-law index ? is weakly anti-correlated (coefficient -0.48) with the electron velocity distribution function at 14.8 keV. The origin of these quiet-time superhalo electrons remains unclear, but since they are present even in the absence of any solar activity, they may be due to resonant wave-particle interactions in the corona or the interplanetary space.

  3. Measurement of the X-ray mass attenuation coefficients of silver in the 5-20?keV range.

    PubMed

    Islam, M Tauhidul; Tantau, Lachlan J; Rae, Nicholas A; Barnea, Zwi; Tran, Chanh Q; Chantler, Christopher T

    2014-03-01

    The X-ray mass attenuation coefficients of silver were measured in the energy range 5-20?keV with an accuracy of 0.01-0.2% on a relative scale down to 5.3?keV, and of 0.09-1.22% on an absolute scale to 5.0?keV. This analysis confirms that with careful choice of foil thickness and careful correction for systematics, especially including harmonic contents at lower energies, the X-ray attenuation of high-Z elements can be measured with high accuracy even at low X-ray energies (<6?keV). This is the first high-accuracy measurement of X-ray mass attenuation coefficients of silver in the low energy range, indicating the possibility of obtaining high-accuracy X-ray absorption fine structure down to the L1 edge (3.8?keV) of silver. Comparison of results reported here with an earlier data set optimized for higher energies confirms accuracy to within one standard error of each data set collected and analysed using the principles of the X-ray extended-range technique (XERT). Comparison with theory shows a slow divergence towards lower energies in this region away from absorption edges. The methodology developed can be used for the XAFS analysis of compounds and solutions to investigate structural features, bonding and coordination chemistry. PMID:24562564

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

    NASA Astrophysics Data System (ADS)

    Troussel, Ph.; Dennetiere, D.; Maroni, R.; Høghøj, P.; Hedacq, S.; Cibik, L.; Krumrey, M.

    2014-12-01

    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. Range measurement of boron isotopes in silicon from 600 keV to 2 MeV

    NASA Astrophysics Data System (ADS)

    Goppelt, P.; Biersack, J. P.; Gebauer, B.; Fink, D.; Bohne, W.; Wilpert, M.; Wilpert, Th.

    1993-06-01

    Ranges of boron isotopes with masses 10 and 11 were measured in silicon for implantation energies of 600 keV, 1.0, 1.5 and 2.0 MeV by use of high-energy elastic recoil detection analysis (HE-ERDA). The measured ranges were compared with TRIM and PRAL calculations. The experimental data show a deviation to larger depth particularly at higher energies. The ratio of the ranges of the isotopes is always lower than theoretically predicted. The experimental results can be interpreted as follows: the electronic stopping, which dominates this energy regime, increases slower than expected. The maximum of the stopping power is shifted towards lower energies and is lower than calculated. In the lower energy range the stopping power must be larger than predicted leading to smaller ranges for energies up to 1 MeV. Our experiment is in good agreement with former range measurements of Behar et al. [Nucl. Instr. and Meth. B34 (1988) 316] who used the very reliable 10B(n, ?) 6Li nuclear reaction technique (neutron depth profiling: NDP), and of Svensson et al. [J. Appl. Phys. 68 (1990) 73] using secondary ion mass spectroscopy (SIMS), who both found this behavior, too.

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

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

    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).

  7. Neutron Scattering Cross Sections for Natural Carbon in the Energy Range 2-133 keV

    Microsoft Academic Search

    O Gritzay; M Gnidak; V Kolotyi; O Korol; V Razbudey; V Venedyktov; J H Richardson; K Sale

    2006-01-01

    Natural carbon is well known as reactor structure material and at the same time as one of the most important neutron scattering standards, especially at energies less than 2 MeV, where the neutron total and neutron scattering cross sections are essentially identical. The best neutron total cross section experimental data for natural carbon in the range 1-500 keV have uncertainties

  8. A galactic component of the diffuse X-ray flux in the range 2-7 keV

    NASA Technical Reports Server (NTRS)

    Protheroe, R. J.; Wolfendale, A. W.; Wdowczyk, J.

    1980-01-01

    An analysis of the spatial distribution of the 2-7 keV X-ray background measured by Uhuru and reported by Schwartz (1979) is presented. The latitude distribution above 10 deg is consistent with a uniform isotropic component comprising the bulk of the radiation plus a galactic part varying from 3% at /b/ = 20 deg to 1% at /b/ = 90 deg. An analysis was made of the residual background based on the work of Warwick, Pye, and Fabian, in terms of a directional anisotropy as indicated by the Compton-Getting effect; the symmetrical galactic contribution was subtracted in the computations. It was shown that the results are consistent with the solar system moving through the 2-7 keV X-ray sea in the same manner as it appears to move with respect to the 2.7 K radiation.

  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

    SciTech Connect

    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. IN-RANGE PROGRESSION SJSU HR: 2/20/13

    E-print Network

    Su, Xiao

    IN-RANGE PROGRESSION GUIDELINES SJSU HR: 2/20/13 SUBJECT: IN-RANGE PROGRESSION DATE: February 19 the compensation requirements for In-Range Progression as stated in Collective Bargaining Unit Agreements for APC, CESUEU, SETC and SUPA. APC An in-range progression is defined as an increase in an employee's pay rate

  11. Excitation and charge transfer to 2s and 2p states in 1 - 20-keV H+-H collisions

    NASA Astrophysics Data System (ADS)

    Fritsch, W.; Lin, C. D.

    1982-08-01

    Electron excitation and transfer to 2s and 2p states in H+-H (1s) collisions is studied in the energy range from 1 to 20 keV with the use of a modified two-center atomic-expansion method. It is shown that the inclusion of united-atom orbitals, in addition to the atomic orbitals of the separated atoms, in a two-center expansion allows for the extension of this method to the low-collision-energy regime. The results of our calculations at low energies from 1 to 5 keV agree with experiments and with the recent multistate molecular-orbital calculations by Kimura and Thorson but differ from the molecular-orbital calculations by Crothers and Hughes. At higher energies our results agree qualitatively with experiments and confirm the dip in 2s and 2p excitation cross sections at E~11 keV. The impact-parameter dependence of excitation and capture probabilities is also examined to illustrate the evolution of the excitation mechanism from the rotational coupling at lower collision energies to the direct excitation process at higher energies.

  12. Neutron scattering measurements in {sup 197}Au from 850 keV to 2.0 MeV

    SciTech Connect

    O`Connor, M.; Chen, J.; Egan, J.J. [and others

    1995-10-01

    Differential elastic and inelastic neutron scattering cross-sections for low lying levels in {sup 197}Au have been measured for incident neutron energies of 1.0 MeV, 1.5 MeV and 2.0 MeV. In addition, the total neutron cross sections in {sup 197}Au was measured from 850 keV to 1.5 MeV. For both experiments the UML 5.5 MV Van-de-Graaff accelerator with a Mobley post acceleration compression system, produced subnanosecond proton pulses which generated neutrons via the {sup 7}Li(p,n) {sup 7}Be reaction.

  13. 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

    SciTech Connect

    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.

  14. plutonium isotopic analysis in the 30 KeV to 210 KeV range

    SciTech Connect

    Vo, Duc T.; Li, T. K. (Tien K.)

    2001-01-01

    Low-Energy Gamma-ray Spectroscopy (LEGS) is a nondestructive assay (NDA) technique developed in the 1980s. In 1999, it was modified to include a physical-based model for the energy dependent efficiency. It uses the gamma rays in the energy range from approximately 30 keV to 210 keV, except the 100-keV region. This energy region provides intense, well-separated gamma rays from the principal isotopes of plutonium. For applications involving small quantities (mg to g) of freshly separated plutonium in various chemical forms, it is ideally suited for accurate real-time or near real-time isotopic analysis. Since the last modification, LEGS has been incorporated into the FRAM code (Fixed-energy Response-function Analysis with Multiple efficiency), version 4. FRAM v4 is capable of analyzing the peaks in the whole energy range from 30 keV to 1 MeV, including the X-ray region. The new capability of analyzing the peaks in the 100-keV region greatly enhances the plutonium analysis in the 30 keV to 2 10 keV ranges of the traditional LEGS. We now can analyze both the freshly separated and aged plutonium with greater accuracy.

  15. Effective atomic numbers for photon energy absorption of essential amino acids in the energy range 1 keV to 20 MeV

    Microsoft Academic Search

    S. R. Manohara; S. M. Hanagodimath

    2007-01-01

    Effective atomic numbers for photon energy-absorption (ZPEAeff) of essential amino acids histidine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine have been calculated by a direct method in the energy region of 1 keV to 20 MeV. The ZPEAeff values have been found to change with energy and composition of the amino acids. The variations of mass energy-absorption coefficient, effective

  16. Effective atomic numbers for photon energy absorption of essential amino acids in the energy range 1 keV to 20 MeV

    Microsoft Academic Search

    S. R. Manohara; S. M. Hanagodimath

    2007-01-01

    Effective atomic numbers for photon energy-absorption (ZPEAeff) of essential amino acids histidine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine have been calculated by a direct method in the energy region of 1keV to 20MeV. The ZPEAeff values have been found to change with energy and composition of the amino acids. The variations of mass energy-absorption coefficient, effective atomic number

  17. 2-20 ns interframe time 2-frame 6.151 keV x-ray imaging on the recently upgraded Z Accelerator: A progress report

    SciTech Connect

    Bennett, G. R.; Smith, I. C.; Shores, J. E.; Sinars, D. B.; Robertson, G.; Atherton, B. W.; Jones, M. C.; Porter, J. L. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185-1193 (United States)

    2008-10-15

    When used for the production of an x-ray imaging backlighter source on Sandia National Laboratories' recently upgraded 26 MA Z Accelerator, the terawatt-class, multikilojoule, 526.57 nm Z-Beamlet laser (ZBL) [P. K. Rambo et al., Appl. Opt. 44, 2421 (2005)], in conjunction with the 6.151 keV (1s{sup 2}-1s2p triplet line of He-like Mn) curved-crystal imager [D. B. Sinars et al., Rev. Sci. Instrum. 75, 3672 (2004); G. R. Bennett et al., Rev. Sci. Instrum. 77, 10E322 (2006)], is capable of providing a high quality x radiograph per Z shot for inertial confinement fusion (ICF), complex hydrodynamics, and other high-energy-density physics experiments. For example, this diagnostic has recently afforded microgram-scale mass perturbation measurements on an imploding ignition-scale 1 mg ICF capsule [G. R. Bennett et al., Phys. Rev. Lett. 99, 205003 (2007)], where the perturbation was initiated by a surrogate deuterium-tritium (DT) fuel fill tube. Using an angle-time multiplexing technique, ZBL now has the capability to provide two spatially and temporally separated foci in the Z chamber, allowing 'two-frame' imaging to be performed, with an interframe time range of 2-20 ns. This multiplexing technique allows the full area of the four-pass amplifiers to be used for the two pulses, rather than split the amplifiers effectively into two rectangular sections, with one leg delayed with respect to the other, which would otherwise double the power imposed onto the various optics thereby halving the damage threshold, for the same irradiance on target. The 6.151 keV two frame technique has recently been used to image imploding wire arrays, using a 7.3 ns interframe time. The diagnostic will soon be converted to operate with p-rather than s-polarized laser light for enhanced laser absorption in the Mn foil, plus other changes (e.g., operation at the possibly brighter 6.181 keV Mn 1s{sup 2}-1s2p singlet line), to increase x-ray yields. Also, a highly sensitive inline multiframe ultrafast (1 ns gate time) digital x-ray camera is being developed [G. R. Bennett et al., Rev. Sci. Instrum. 77, 10E322 (2006)] to extend the system to 'four-frame' and markedly improve the signal-to-noise ratio. [At present, time-integrating Fuji BAS-TR2025 image plate (scanned with a Fuji BAS-5000 device) forms the time-integrated image-plane detector.].

  18. The Hard X-Ray 20-40 keV AGN Luminosity Function

    NASA Astrophysics Data System (ADS)

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

    2006-11-01

    We have compiled a complete extragalactic sample based on ~25,000 deg2 to a limiting flux of 3×10-11 ergs cm-2 s-1 (~7000 deg2 to a flux limit of 10-11 ergs cm-2 s-1) in the 20-40 keV band with INTEGRAL. We have constructed a detailed exposure map to compensate for effects of nonuniform exposure. The flux-number relation is best described by a power law with a slope of ?=1.66+/-0.11. The integration of the cumulative flux per unit area leads to f20-40 keV=2.6×10-10 ergs cm-2 s-1 sr-1, 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 double-power-law form with an index of ?1=0.8 below and ?2=2.1 above the turnover luminosity of L*=2.4×1043 ergs s-1. The emissivity of all INTEGRAL AGNs per unit volume is W20-40keV(>1041 ergs s-1)=2.8×1038 ergs s-1 h370 Mpc-3. These results are consistent with those derived in the 2-20 keV energy band and do not show a significant contribution by Compton-thick objects. Because the sample used in this study is truly local (z¯=0.022), only limited conclusions can be drawn for the evolution of AGNs in this energy band.

  19. Solar Wind ~20-300 keV Superhalo Electrons

    NASA Astrophysics Data System (ADS)

    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-?, with ? 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 ? show a good correlation with the sunspot number, with larger density and softer spectrum (?~ 6-8) at solar maximum, and smaller density and harder spectrum (?~ 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.

  20. An in-vacuum x-ray diffraction microscope for use in the 0.7-2.9 keV range

    SciTech Connect

    Vine, D. J. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); School of Physics, University of Melbourne, Victoria 3010 (Australia); Argonne National Laboratory, Argonne, Illinois 60439 (United States); Williams, G. J. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Clark, J. N. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); Department of Physics, La Trobe University, Bundoora, Victoria 3086 (Australia); London Centre for Nanotechnology, University College, London WC1E 6BT (United Kingdom); Putkunz, C. T.; Abbey, B.; Nugent, K. A. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); School of Physics, University of Melbourne, Victoria 3010 (Australia); Pfeifer, M. A. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); Cornell High Energy Synchrotron Source, Cornell University, Ithaca, New York 14850 (United States); Legnini, D.; Roehrig, C.; Wrobel, E.; McNulty, I. [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Huwald, E. [Department of Physics, La Trobe University, Bundoora, Victoria 3086 (Australia); Riessen, G. van; Peele, A. G. [Australian Research Council Centre of Excellence for Coherent X-ray Science (Australia); Department of Physics, La Trobe University, Bundoora, Victoria 3086 (Australia); Beetz, T.; Irwin, J.; Feser, M.; Hornberger, B. [Xradia, Inc., 4385 Hopyard Road, Pleasanton, California 94588 (United States)

    2012-03-15

    A dedicated in-vacuum coherent x-ray diffraction microscope was installed at the 2-ID-B beamline of the Advanced Photon Source for use with 0.7-2.9 keV x-rays. The instrument can accommodate three common implementations of diffractive imaging; plane wave illumination; defocused-probe (Fresnel diffractive imaging) and scanning (ptychography) using either a pinhole, focused or defocused probe. The microscope design includes active feedback to limit motion of the optics with respect to the sample. Upper bounds on the relative optics-to-sample displacement have been measured to be 5.8 nm(v) and 4.4 nm(h) rms/h using capacitance micrometry and 27 nm/h using x-ray point projection imaging. The stability of the measurement platform and in-vacuum operation allows for long exposure times, high signal-to-noise and large dynamic range two-dimensional intensity measurements to be acquired. Finally, we illustrate the microscope's stability with a recent experimental result.

  1. Mutagenic effect of a keV range N + beam on mammalian cells

    NASA Astrophysics Data System (ADS)

    Feng, Huiyun; Wu, Lijun; Yu, Lixiang; Han, Wei; Liu, Xuelan; Yu, Zengliang

    2005-07-01

    The radiobiological effects of a keV (5-20 keV) range nitrogen ion (N +) beam on mammalian cells were studied, particularly with regard to the induction of mutation in the cell genome. The experiment demonstrated that the 20 keV N + beam, which resulted in cell death to a certain extent, induced a 2-3 fold increase in the mutation rates at the CD59 gene locus of the mammalian A L cells as compared to the control. Within certain fluence ranges (0-6 × 10 14 N +/cm 2), the cell survival displayed a down-up-down pattern which is similar to the phenomenon known as 'hyper-radiosensitivity' manifested under low-dose irradiation; the CD59 mutation rate firstly showed a gradual rise up to a 3-fold increment above the background level as the ion fluence went up to 4 × 10 14 N +/cm 2, after this peak point however, a downtrend appeared though the ion fluence increased further. It was also observed that the fraction of CD59 mutation bears no proportional relation to ion energy in further experiments of mutation induction by N + beams with the incident energies of 5, 10, 15 and 20 keV at the same fluence of 3 × 10 14 N +/cm 2. Analyses of the deletion patterns of chromosome 11 in CD59- mutants induced by 5-20 keV N + beams showed that these ions did not result in large-size chromosome deletions in this mammalian cell system. A preliminary discussion, suggesting that the mutagenic effect of such low-energy ion influx on mammalian cells could result from multiple processes involving direct collision of particles with cellular DNA, and cascade atomic and molecular reactions due to plentiful primary and secondary particles, was also presented. The study provided the first glimpse into the roles low-energy ions may play in inducing mutagenesis in mammalian cells, and results will be of much value in helping people to understand the contribution of low-energy ions to radiological effects of various ionising radiations.

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

    NASA Technical Reports Server (NTRS)

    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.

  3. Analysis of experimental data on neutron-proton scattering in the energy range between 0 and 150 keV

    NASA Astrophysics Data System (ADS)

    Babenko, V. A.; Petrov, N. M.

    2009-04-01

    Experimental data on neutron-proton scattering in the energy range between 0 and 150 keV are analyzed by using various sets of effective-range parameters. It is shown that, in contrast to the parameters corresponding to the phase shifts of a Nijmegen group, the parameters corresponding to the experimental phase shifts reported by a group from George Washington University (GWU group) lead to very good agreement between the calculated cross sections and their experimental counterparts in the energy region under consideration. On the basis of the experimental value of the cross section for neutron—proton scattering at an energy of 2 keV, the total cross section for neutron-proton scattering at zero energy was found to be ? 0 = 20.428(16) b, which is in very good agreement with a value of ? 0 = 20.423(9) b, which was obtained as the weighted mean of the cross sections presented by Houke and Hurst. It is shown that, in the energy region around several tens of keV units, the effective-range parameters matched with Dilg’s cross-section value of ? 0 = 20.491(14) b lead to calculated cross sections whose values are in excess of their experimental counterparts.

  4. Comparison of TOF-ERDA and nuclear resonance reaction techniques for range profile measurements of keV energy implants

    Microsoft Academic Search

    J. Jokinen; J. Keinonen; P. Tikkanen; A. Kuronen; T. Ahlgren; K. Nordlund

    1996-01-01

    A comparative study on the range measurements of keV energy implants by the Time-of-Flight Elastic Recoil Detection Analysis (TOF-ERDA) and conventionally used nuclear resonance reaction methods has been performed for 20–100 keV 15N+ ions implanted into crystalline silicon. Range profiles of 15N atoms were chosen because they can be measured accurately using a very strong and narrow resonance at Ep

  5. High angular resolution cosmic X-ray astronomy observations in the energy range 0.15-2 keV and XUV observations of nearby stars from an attitude controlled rocket

    NASA Technical Reports Server (NTRS)

    Garmire, G. P.

    1974-01-01

    The construction of a two dimensional focusing Wolter Type I mirror system for X-ray and XUV astronomical observations from an Astrobee F sounding rocket is described. The mirror design goal will have a one degree field, a 20-arc seconds resolution, an effective area of about 50 sq cm at 1 keV and 10 sq cm at 0.25 keV on axis. A star camera provides aspect data to about 15-arc seconds. Two detectors are placed at the focus with an interchange mechanism to allow a detector change during flight. The following specific developments are reported: (1) position sensitive proportional counter development; (2) channel plate multiplier development; (3) telescope mirror development and payload structure; (4) Australian rocket flight results; (5) Comet Kohoutek He I observation; and (6) Vela, Puppis A, and Gem-Mon bright patch observations.

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

    SciTech Connect

    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.

  7. Thermal conductivity of highly porous Si in the temperature range 4.2 to 20 K

    PubMed Central

    2014-01-01

    We report on experimental results of the thermal conductivity k of highly porous Si in the temperature range 4.2 to 20 K, obtained using the direct current (dc) method combined with thermal finite element simulations. The reported results are the first in the literature for this temperature range. It was found that porous Si thermal conductivity at these temperatures shows a plateau-like temperature dependence similar to that obtained in glasses, with a constant k value as low as 0.04 W/m.K. This behavior is attributed to the presence of a majority of non-propagating vibrational modes, resulting from the nanoscale fractal structure of the material. By examining the fractal geometry of porous Si and its fractal dimensionality, which was smaller than two for the specific porous Si material used, we propose that a band of fractons (the localized vibrational excitations of a fractal lattice) is responsible for the observed plateau. The above results complement previous results by the authors in the temperature range 20 to 350 K. In this temperature range, a monotonic increase of k with temperature is observed, fitted with simplified classical models. The extremely low thermal conductivity of porous Si, especially at cryogenic temperatures, makes this material an excellent substrate for Si-integrated microcooling devices (micro-coldplate). PACS 61.43.-j; 63.22.-m; 65.8.-g PMID:25114631

  8. A 20 keV electron gun system for the electron irradiation experiments

    Microsoft Academic Search

    S. K. Mahapatra; S. D. Dhole; V. N. Bhoraskar

    2005-01-01

    An electron gun consisting of cathode, focusing electrode, control electrode and anode has been designed and fabricated for the electron irradiation experiments. This electron gun can provide electrons of any energy over the range20keV, with current upto 50?A. This electron gun and a Faraday cup are mounted in the cylindrical chamber. The samples are fixed on the Faraday cup

  9. FHBS calculation of ionized electron angular and energy distribution following the p+H collision at 20 keV 

    E-print Network

    Fu, Jun

    2004-11-15

    than 0:5% for 20 keV projectile energy and less than 2% for 48 keV projectile energy after h partial waves are included. Table II. Total Cross Sections from Two B1 Methods s-d s-f s-g s-h All-Partial Wave 20 keV 1.95 2.06 2.09 2.10 2.11 48 keV 1.69 1...- ing angles, but not reliable at large backward scattering angles. 27 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0 20 40 60 80 100 120 140 160 180 ds/dq (10 -16 cm 2 /degree) Angle (degree) s-d s-f s-h All Fig. 1. Angular distribution of electrons at 20 ke...

  10. Complex Refractive Index of Ammonium Nitrate in the 2-20 micron Spectral Range

    NASA Technical Reports Server (NTRS)

    Jarzembski, Maurice A.; Norman, Mark L.; Fuller, Kirk A.; Srivastava, Vandana; Cutten, Dean R.

    2002-01-01

    Using high resolution Fourier Transform Infrared Spectroscopy (FTIR) absorbance/transmittance spectral data for ammonium sulfate (AMS), calcium carbonate (CAC) and ammonium nitrate (AMN), comparisons were made with previously published complex refractive indices data for AMS and CAC to infer experimental parameters to determine the imaginary refractive index for AMN in the infrared wavelength range from 2 to 20 microns. Kramers-Kronig mathematical relations were applied to calculate the real refractive index for the three compositions. Excellent agreement for AMS and CAC with the published values was found, validating the complex refractive indices obtained for AMN. Backscatter calculations using a lognormal size distribution for AMS, AMN, and CAC aerosols were performed to show differences in their backscattered spectra.

  11. 236 U total neutron cross section in the energy range 1.8-734 keV

    Microsoft Academic Search

    O. A. Purtov; L. L. Litvinskii; A. V. Murzin; G. M. Novoselov

    1993-01-01

    The total neutron cross section for 236U is studied in a large number of experimental works: [2-4] - in the region of the resolved resonances by the time-of-flight method and [5] in the region of unresolved resonances (above 5 keV), where the total neutron cross section and the cross section for radiative capture of neutrons in the range 5-800 keV

  12. High-resolution spectra of 20-300 keV hard X-rays from electron precipitation over Antarctica

    SciTech Connect

    Smith, D.M. [Univ. of Maryland, College Park, MD (United States)] [Univ. of Maryland, College Park, MD (United States); Lin, R.P. [Univ. of California, Berkeley, CA (United States)] [Univ. of California, Berkeley, CA (United States); Hurley, A.K. [Univ. of California, Berkeley, CA (United States)] [and others] [Univ. of California, Berkeley, CA (United States); and others

    1995-10-01

    In December 1990, a set of liquid-nitrogen-cooled germanium hard X-ray and gamma-ray spectrometers was flown aboard a high-altitude balloon from McMurdo, Antarctica, for solar, astrophysical, and terrestrial observations. This flight was the first circumnavigation ({approximately}9-day duration) of the Antarctic continent by a large (800,000-cubic-meter) balloon. Bremsstrahlung hard X-ray emission extending up to {approximately}300 keV, from the precipitation of high-energy electrons, was observed on six separate occasions over the auroral zone, all during low geomagnetic activity (K{sub p}{le} 2+). All events were consistent with emission at the trapping boundary; observation over the polar cap showed no precipitation. The authors present the first high-resolution ({Delta}E {approximately}2 keV) full width at half maximum (FWHM) spectra of this hard X-ray emission in the energy range 20-300 keV. The observed count spectra are deconvolved by model-independent techniques to photon spectra and then to the precipitating electron spectra. The spectral hardness shows all inverse relation with L as expected. This result suggests that high-resolution spectroscopy could be extremely effective in characterizing electron precipitation if coupled with imaging capability. 26 refs., 9 figs., 1 tab.

  13. Monte Carlo calculations of energy deposition distributions of electrons below 20 keV in protein.

    PubMed

    Tan, Zhenyu; Liu, Wei

    2014-05-01

    The distributions of energy depositions of electrons in semi-infinite bulk protein and the radial dose distributions of point-isotropic mono-energetic electron sources [i.e., the so-called dose point kernel (DPK)] in protein have been systematically calculated in the energy range below 20 keV, based on Monte Carlo methods. The ranges of electrons have been evaluated by extrapolating two calculated distributions, respectively, and the evaluated ranges of electrons are compared with the electron mean path length in protein which has been calculated by using electron inelastic cross sections described in this work in the continuous-slowing-down approximation. It has been found that for a given energy, the electron mean path length is smaller than the electron range evaluated from DPK, but it is large compared to the electron range obtained from the energy deposition distributions of electrons in semi-infinite bulk protein. The energy dependences of the extrapolated electron ranges based on the two investigated distributions are given, respectively, in a power-law form. In addition, the DPK in protein has also been compared with that in liquid water. An evident difference between the two DPKs is observed. The calculations presented in this work may be useful in studies of radiation effects on proteins. PMID:24519325

  14. Feasibility study for DEXA using synchrotron CT at 20-35 keV

    NASA Astrophysics Data System (ADS)

    Midgley, S. M.

    2013-02-01

    A nonlinear model for the x-ray linear attenuation coefficient ? is employed for dual energy x-ray analysis (DEXA). Nonlinear simultaneous equations formed by ? and energy dependent model parameters are solved for the electron density Ne and fourth compositional ratio R4 which has the same ‘units’ as the atomic number. Computed tomography data was acquired at 20-35 keV using bending magnet synchrotron radiation, a double crystal monochromator, a rotation stage and an area detector. Test objects contained liquid samples as mixtures of ethanol, water and salt solutions with known density and composition. Various noise sources are identified and give ? uncertainties of 1-2%. A fan beam geometry allowed the detection of forward scattered radiation with measured ? being 6% lower than expectations for a narrow beam. Energy dependent model parameters were obtained by solving linear simultaneous equations formed by ? and material parameters based upon Ne and R4. DEXA accuracy was studied as a function of photon energy and sample composition. Propagation of errors analysis identifies the importance of the fractional compositional cross-products whose difference at the two beam energies should exceed 0.1, requiring 10 keV or more separation. For a reasonable approximation for the adjustable model parameters, the mean difference between the DEXA solution and true values (?Ne, ?R4) are (1.0%, 0.5%) for soft tissue and (1.5%, 0.8%) for bone like samples.

  15. Efficiency of Scintillator Materials in the Energy Range 8.0-32.0 keV

    SciTech Connect

    Kinney, J H; Haupt, D L

    2002-07-01

    X-ray microtomography requires the measurement of x-ray attenuation along ray paths through a specimen, and on the inversion of these data to obtain a spatially resolved mapping of the microstructure of the specimen. To do this efficiently, two-dimensional array detectors are often used to measure the transmitted x-rays by capturing and recording each x-ray incident on the detector. The highest resolution CT instruments perform this by converting the incident x-rays to visible light, and then focusing this light onto a charge-coupled-device (CCD) detector. The light output of the scintillator (photons per incident x-ray), the numerical aperture of the optical lens system, and the quantum efficiency of the CCD govern the efficiency of the detection process. Several years earlier, our group performed an investigation aimed at determining the best scintillator material for high-resolution synchrotron CT. The selection criteria included light output in the 8-32 keV energy range, the spatial resolution of the scintillator, the wavelength of the scintillation radiation, and the stability and ease of polishing of the scintillator. A list of the scintillators that we considered, with the exceptions of the more recently developed glass scintillators, is provided in Table 1. Among these scintillators, we concluded that single crystal cadmium tungstate was optimum; we have used this material in all subsequent synchrotron CT systems. Since this original study, several doped-glass scintillators have become available. The LSO (Lu orthosilicates) scintillators, developed for PET scanning, show considerable light output at high energy (energies above 500 keV). Theoretically, the light output of these scintillators should be twice that of the cadmium tungstate. The purpose of this study was to determine the efficiency of two such scintillators (LSO:Yt and IQI-401 high density terbium activated glass) in the energy range from 8-32 keV.

  16. Simulations of Microchannel Plate Sensitivity to <20 keV X-rays as a Function of Energy and Incident Angle

    SciTech Connect

    Kruschwitz, Craig [NSTec; Wu, M. [SNL; Rochau, G. A. [SNL

    2013-06-13

    We present results of Monte Carlo simulations of microchannel plate (MCP) response to x-rays in the 250 eV to 20 keV energy range as a function of both x-ray energy and impact angle. The model is based on the model presented in Rochau et al. (2006). However, while the Rochau et al. (2006) model was two-dimensional, and their results only went to 5 keV, our results have been expanded to 20 keV, and our model has been incorporated into a three-dimensional Monte Carlo MCP model that we have developed over the past several years (Kruschwitz et al. 2011). X-ray penetration through multiple MCP pore walls is increasingly important above 5 keV. The effect of x-ray penetration through multiple pores on MCP performance was studied and is presented.

  17. Injection and diffusive transport of suprathermal through energetic solar flare protons (35 keV to 20 MeV)

    NASA Technical Reports Server (NTRS)

    Beeck, J.; Mason, G. M.; Hamilton, D. C.; Marsden, R. G.; Sanderson, T. R.

    1990-01-01

    Consideration is given to the injection and interplanetary propagation of low-energy protons caused by the solar particle event of July 20, 1981, in which flare protons in the range from 35 keV to 20 MeV were observed by instruments on ISEE 3. The observed time-intensity and time-anisotropy profiles were fitted over the entire energy range using a model based on the spherically symmetric Fokker-Plank equation, including convection, diffusion, and adiabatic deceleration. The results are used to discuss the behavior of the radial interplanetary diffusion coefficient and the scattering mean free path for protons. Also, evidence is found for diffusive coronal shock acceleration of protons during the event.

  18. First direct high-precision energy determination for the 8.4 and 20.7 keV nuclear transitions in 169Tm

    NASA Astrophysics Data System (ADS)

    Inoyatov, A. Kh.; Kovalík, A.; Filosofov, D. V.; Ryšavý, M.; Perevoshchikov, L. L.; Gurov, Yu. B.

    2015-06-01

    Energies of 8410.1 ± 0.4, 20743.9 ± 0.3, and 63121.6 ± 1.2 eV were determined for the 8.4 keV M1 + E2, 20.7 keV M1 + E2, and 63.1 keV E1 nuclear transitions in 169Tm (generated in the EC decay of 169Yb, respectively, by means of the internal conversion electron spectroscopy. The 169Yb sources used were prepared by vacuum evaporation deposition on polycrystalline carbon and platinum foils as well as by ion implantation at 30keV into a polycrystalline aluminum foil. The relevant conversion electron spectra were measured by a high-resolution combined electrostatic electron spectrometer at 7 eV instrumental resoluition. Values of 0.0326(14) and 0.0259(17) were derived from our experimental data for the E2 admixture parameter |? ( E2/ M1)| for the 8.4 and 20.7 keV transitions, respectively. A possible effect of nuclear structure on multipolarity of the 20.7 keV transition was also investigated.

  19. Optical constants for hard x-ray multilayers over the energy range E = 35 180 keV

    E-print Network

    of a prototype W/SiC multilayer coating over the energy range E=35 ­ 100 keV, and we compare the measured, W, Pt, C, B4C, Si and SiC were deposited by magnetron sputtering onto superpolished optical flats the reflectance of prototype hard X-ray W/Si and W/SiC multilayers designed for use above 100 keV; we found

  20. Electron loss and transfer for 20--110-keV iodine--rare-gas collisions

    SciTech Connect

    Hird, B.; Orakzai, M.W.; Rahman, F.

    1989-05-15

    Atomic cross sections have been measured for the loss and transfer of an electron during a collision between a neutral iodine atom and a rare-gas atom. The neutral iodine beam, with energy between 20 to 110 keV, was unlikely to contain a significant mixture of metastable-state atoms because it was produced by neutralizing a negative-iodine-ion beam. The sigma/sub 0+/ cross section is largest for the argon and krypton targets, not for xenon, as might have been expected. The sigma/sub 0-/ cross section is very small for the light targets and only becomes appreciable for xenon at the highest energy used.

  1. Monochromator harmonic content measurements and calculations at energies above 20 keV

    SciTech Connect

    Chapman, D.; Moulin, H.; Garrett, R.F.

    1991-01-01

    Measurements of the harmonic content from single and double crystal silicon monochromators have been made in the 20 to 100 keV at the X17 Superconducting Wiggler Beamline at the NSLS. These measurements are compared with calculations which estimate the monochromatic beam harmonic content and the detection system efficiency with good agreement. At high photon energies ( > 20keV), the scattering of x-rays from an amorphous scatterer is dominated by the inelastic Compton process. At large scattering angles this will completely overwhelm the more forward directed elastic scattering. The Compton x-ray energy shift is large enough to make the distinction between elastic and Compton scattering unambiguous when a spectrum is acquired with a solid state detector. This shift, which is energy dependent, allows the measurement of the relative harmonic intensity in a way that is not affected by pulse pileup in the detector and electronics. The present measurements were done to assess the level of harmonic contamination from two monochromator systems both used on the X17 beamline: the single crystal type monochromator for the Digital Subtraction Coronary Angiography project; and the double crystal monochromator being developed for the Multiple Energy Computed Tomography (MECT) project and the Materials Science program. 5 refs.

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

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

  3. Characterizations of MCP performance in the hard x-ray range (6–25 keV)

    SciTech Connect

    Wu, Ming, E-mail: minwu@sandia.gov; Rochau, Greg [Sandia National Laboratory, Albuquerque, New Mexico 87185 (United States); Moy, Ken [Special Technology Laboratories, NSTec, Santa Barbara, California 93111-2335 (United States); Kruschwitz, Craig [National Security Technologies, LLC, Los Alamos Operations, Los Alamos, New Mexico 87544 (United States)

    2014-11-15

    MCP detector performance at hard x-ray energies from 6 to 25 keV was recently investigated using NSLS beamline X15A at BNL. Measurements were made with an NSTec Gen-II (H-CA-65) framing camera, based on a Photonis MCP with ?10 ?m in diameter pores, ?12 ?m center-center spacing, an L/D ratio of 46, and a bias angle of 8°. The MCP characterizations were focused on (1) energy and angle dependent sensitivity, (2) energy and angle dependent spatial resolution, (3) energy dependent gain performance, and (4) energy dependent dynamic range. These measurement corroborated simulation results using a Monte Carlo model that included hard x-ray interactions and the subsequent electron cascade in the MCP.

  4. K X-ray production cross sections in aluminium for 15, 20 and 25 keV protons

    NASA Astrophysics Data System (ADS)

    do Carmo, S. J. C.; Borges, F. I. G. M.; Trindade, A. M. F.; Conde, C. A. N.

    2012-12-01

    A low-energy particle accelerator has been used to determine experimentally low-energy X-ray production cross sections through the irradiation of thick targets with ions with energies up to 25 keV/ion charge by measuring thick target yields. We obtained aluminium K- X-ray production cross sections values of 8.4 × 10-4, 1.3 × 10-3 and 1.8 × 10-3 barn for 15, 20 and 25 keV protons, respectively. Although there are no results in the literature for such low-energy impinging protons for comparison, the results presented here are in good agreement with the general trend exhibited for higher energy ranges.

  5. Isotopic Mo Neutron Total Cross Section Measurements in the Energy Range 1 to 620 keV

    NASA Astrophysics Data System (ADS)

    Bahran, R.; Barry, D.; Leinweber, G.; Rapp, M.; Block, R.; Daskalakis, A.; McDermott, B.; Piela, S.; Blain, E.; Danon, Y.

    2014-05-01

    A series of new total cross section measurements for the stable molybdenum isotopes of 92,94,95,96,98,100Mo covering the energy range between 1 keV and 620 keV was performed at the Gaerttner LINAC Center at Rensselaer Polytechnic Institute. New high-accuracy resonance parameters were extracted from an analysis of the data using the multilevel R-matrix Bayesian code SAMMY. In the unresolved resonance region, average resonance parameters and fits to the total cross sections were obtained using the Bayesian Hauser-Feshbach statistical model code FITACS.

  6. Stability of Extraterrestrial Glycine under Energetic Particle Radiation Estimated from 2 keV Electron Bombardment Experiments

    NASA Astrophysics Data System (ADS)

    Maté, B.; Tanarro, I.; Escribano, R.; Moreno, M. A.; Herrero, V. J.

    2015-06-01

    The destruction of solid glycine under irradiation with 2 keV electrons has been investigated by means of IR spectroscopy. Destruction cross sections, radiolysis yields, and half-life doses were determined for samples at 20, 40, 90, and 300 K. The thickness of the irradiated samples was kept below the estimated penetration depth of the electrons. No significant differences were obtained in the experiments below 90 K, but the destruction cross section at 300 K was larger by a factor of 2. The radiolysis yields and half-life doses are in good accordance with recent MeV proton experiments, which confirms that electrons in the keV range can be used to simulate the effects of cosmic rays if the whole sample is effectively irradiated. In the low temperature experiments, electron irradiation leads to the formation of residues. IR absorptions of these residues are assigned to the presence CO2, CO, OCN?, and CN? and possibly to amide bands I to III. The protection of glycine by water ice is also studied. A water ice film of ?150 nm is found to provide efficient shielding against the bombardment of 2 keV electrons. The results of this study show also that current Monte Carlo predictions provide a good global description of electron penetration depths. The lifetimes estimated in this work for various environments ranging from the diffuse interstellar medium to the inner solar system, show that the survival of hypothetical primeval glycine from the solar nebula in present solar system bodies is not very likely.

  7. Search for Anomalous Scattering of keV Neutrons from H2O-D2O Mixtures R. Moreh,1,2,* R. C. Block,2

    E-print Network

    Danon, Yaron

    Search for Anomalous Scattering of keV Neutrons from H2O-D2O Mixtures R. Moreh,1,2,* R. C. Block,2 (Received 20 January 2005; published 12 May 2005) We measured the neutron scattering intensities from pure. This study is relevant to the problem of quantum entanglement. The neutrons were generated from an electron

  8. Comparison between an event-by-event Monte Carlo code, NOREC, and ETRAN for electron scaled point kernels between 20 keV and 1 MeV.

    PubMed

    Cho, Sang Hyun; Vassiliev, Oleg N; Horton, John L

    2007-03-01

    An event-by-event Monte Carlo code called NOREC, a substantially improved version of the Oak Ridge electron transport code (OREC), was released in 2003, after a number of modifications to OREC. In spite of some earlier work, the characteristics of the code have not been clearly shown so far, especially for a wide range of electron energies. Therefore, NOREC was used in this study to generate one of the popular dosimetric quantities, the scaled point kernel, for a number of electron energies between 0.02 and 1.0 MeV. Calculated kernels were compared with the most well-known published kernels based on a condensed history Monte Carlo code, ETRAN, to show not only general agreement between the codes for the electron energy range considered but also possible differences between an event-by-event code and a condensed history code. There was general agreement between the kernels within about 5% up to 0.7 r/r (0) for 100 keV and 1 MeV electrons. Note that r/r (0) denotes the scaled distance, where r is the radial distance from the source to the dose point and r (0) is the continuous slowing down approximation (CSDA) range of a mono-energetic electron. For the same range of scaled distances, the discrepancies for 20 and 500 keV electrons were up to 6 and 12%, respectively. Especially, there was more pronounced disagreement for 500 keV electrons than for 20 keV electrons. The degree of disagreement for 500 keV electrons decreased when NOREC results were compared with published EGS4/PRESTA results, producing similar agreement to other electron energies. PMID:17219152

  9. FHBS calculation of ionized electron angular and energy distribution following the p+H collision at 20 keV

    E-print Network

    Fu, Jun

    2004-11-15

    A Finite Hilbert Basis Set (FHBS) method to calculate the angular and energy distribution of ejected electrons in an ion-atom collision is presented. This method has been applied to the p + H collision at 20 keV impact energy. An interference effect...

  10. Measurements and assessment of 12C(d,p?)13C reaction cross sections in the deuteron energy range 740-2000 keV for analytical applications

    NASA Astrophysics Data System (ADS)

    Csedreki, L.; Uzonyi, I.; Szíki, G. Á.; Szikszai, Z.; Gyürky, Gy.; Kiss, Á. Z.

    2014-06-01

    The total cross sections of the 12C(d,p?1)13C (E? = 3089 keV), 12C(d,p?2)13C (E? = 3684 keV) and 12C(d,p?3)13C (E? = 3854 keV) reactions, as well as differential cross sections for (d,po), (d,p1) reactions and (d,d0) elastic scattering were determined in the 740-2000 keV deuteron energy range using a self-supporting natural carbon foil and detecting the gamma-rays and particles simultaneously. In order to test the validity of the measured gamma-ray producing cross sections, benchmark experiments were performed using kapton foils with two different thicknesses. Both the obtained gamma- and particle production cross section results were compared with data existing in literature, and in the case of (d,po) the experimental differential cross section data were compared also with the theoretical evaluated values.

  11. Two-photon above-threshold ionization of hydrogen over the photon energy range from 15 eV to 50 keV

    SciTech Connect

    Florescu, Viorica; Budriga, Olimpia; Bachau, Henri [Department of Physics and Centre for Advanced Quantum Physics, University of Bucharest, MG-11, R-077125 Bucharest-Magurele (Romania); National Institute for Laser, Plasma and Radiation Physics, R-077125 Bucharest-Magurele (Romania); Centre des Lasers Intenses et Applications, Universite Bordeaux I-CNRS-CEA, F-33405 Talence Cedex (France)

    2011-09-15

    We investigate the absorption of two identical photons from the ground state of hydrogen-like atoms over an energy range that extends beyond that explored up to now. Our approach is based on a hybrid formula, valid in second-order perturbation theory, in which the A{sup 2} contribution from the nonrelativistic Hamiltonian is treated exactly, while the A{center_dot}P contribution is calculated in dipole approximation. We find that, at least up to 50 keV, the nonrelativistic dipole approximation, based only on the A{center_dot}P contribution, determines the values of the total cross section. Our numerical results, covering photon energies from 90 nm (13.7 eV) to 0.0248 nm (50 keV) are in very good agreement with most previous theoretical works. Differences with recent results are discussed.

  12. Emission Lines between 1 and 2 keV in Cometary X-Ray Spectra

    NASA Astrophysics Data System (ADS)

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

    2013-01-01

    We present the detection of new cometary X-ray emission lines in the 1.0-2.0 keV range using a sample of comets observed with the Chandra X-Ray Observatory and ACIS spectrometer. We have selected five comets from the Chandra sample with good signal-to-noise spectra. The surveyed comets are C/1999 S4 (LINEAR), C/1999 T1 (McNaught-Hartley), 153P/2002 (Ikeya-Zhang), 2P/2003 (Encke), and C/2008 8P (Tuttle). We modeled the spectra with an extended version of our solar wind charge exchange (SWCX) emission model. Above 1 keV, we find Ikeya-Zhang to have strong emission lines at 1340 and 1850 eV which we identify as being created by SWCX lines of Mg XI and Si XIII, respectively, and weaker emission lines at 1470, 1600, and 1950 eV formed by SWCX of Mg XII, Mg XI, and Si XIV, respectively. The Mg XI and XII and Si XIII and XIV lines are detected at a significant level for the other comets in our sample (LS4, MH, Encke, 8P), and these lines promise additional diagnostics to be included in SWCX models. The silicon lines in the 1700-2000 eV range are detected for all comets, but with the rising background and decreasing cometary emission, we caution that these detections need further confirmation with higher resolution instruments.

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

    NASA Astrophysics Data System (ADS)

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

    2010-04-01

    Hind-limb suspension (HLS) of rats is a NASA validated model of simulated weightlessness. This study examines the effects of microgravity on the skeletal system of rats to assess whether or not exposure of rats to HLS for one week will induce alteration of structural features in selected bones. Four groups of rats were used: two unsuspended controls and two suspended groups. Body weight, food, and water intake were monitored daily before and after suspension. X-rays were measured by a liquid nitrogen cooled Si(li) detector on a Scanning Electron Microscope (SEM) that provided the 20 keV electron beam. X-ray data were collected from square cross sections between 100 ?m2 and 104 ?m2. The bones were measured for elemental levels of calcium, phosphorus, oxygen and carbon from both control and HLS rats. The average body weight of all HLS groups decreased compared to their respective unsuspended controls. Food and water intake was also lower in both suspended groups. A correlation among HLS and control samples in terms of the distribution of the primary elements was found in the bone tissue when analyzed as a function of position along the hind-leg and within the cross sections.

  14. Lifetime of the 2795 keV Jpi = 1+\\/2 level in 21Ne

    Microsoft Academic Search

    L. K. Fifield; W. N. Catford; E. F. Garman; I. F. Wright

    1983-01-01

    The mean life of the 2795 keV 1+\\/2 level in 21Ne has been measured using the 21C(13C, alphagamma)21Ne reaction and a variant of the Doppler-shift attenuation method. The result obtained was tau = 7.9 +\\/- 1.8 fs. In addition, the separation of the 2789 (1-\\/2) and 2795 (1+\\/2) keV levels in 21Ne been measured as 5.91 +\\/- 0.31 keV. The

  15. Maskless nano-implant of 20 keV Ga+ in bulk Si(1 0 0) substrates

    NASA Astrophysics Data System (ADS)

    Milazzo, R. G.; D'Arrigo, G.; Mio, A. M.; Rimini, E.; Spinella, C.; Peto, L.; Nadzeyka, A.; Bauerdick, S.

    2014-12-01

    Multidirectional SPEG (Solid Phase Epitaxial Growth) of silicon has been investigated in micro and nanoamorphous structures generated on a crystalline substrate by a nano-sized ion beam, Gaussian shaped and with a standard deviation of about 5 nm. The 20 keV Ga+ ions were implanted at a fluence of 5 × 1014 ions cm-2 in a bulk Si(1 0 0) single crystal. Two structures were used for the implants: circular regions of 100 nm and 1 ?m diameters respectively and straight lines 10 nm in width and few microns in length along (1 0 0) or (1 1 0) directions. The lateral spread of ions has been taken into account in the damage estimation. Transmission Electron Microscopy indicates that the structures are made of an amorphous core surrounded by a defective and filamentary shell. The recovery of the damaged outer regions promptly occurs during the early stages of the thermal treatment at 500-600 °C for all the structures. By prolonging annealing time, re-crystallization of the amorphous cores is achieved too by the movement of the underneath crystal-amorphous interface. The re-growth is almost defects free when the contribution of the crystalline seed below the structures is present, defective and twin mediated if it misses as in the thinnest regions of the specimen.

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

    NASA Astrophysics Data System (ADS)

    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.

  17. High Spatial Resolution STXM at 6.2 keV Photon Energy

    NASA Astrophysics Data System (ADS)

    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.

  18. High Spatial Resolution STXM at 6.2 keV Photon Energy

    SciTech Connect

    Vila-Comamala, Joan; Kewish, Cameron M.; Thibault, Pierre; Guzenko, Vitaliy; Gorelick, Sergey; Menzel, Andreas; Bunk, Oliver; David, Christian [Paul Scherrer Institut, CH-5232 Villigen (Switzerland); Dierolf, Martin; Pfeiffer, Franz [Technische Universitaet Muenchen, D-85748 Garching (Germany); Pilvi, Tero; Faerm, Elina; Ritala, Mikko [Department of Chemistry, FI-00014 University of Helsinki (Finland)

    2010-04-06

    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.

  19. Comparison of GATE/GEANT4 with EGSnrc and MCNP for electron dose calculations at energies between 15 keV and 20 MeV

    NASA Astrophysics Data System (ADS)

    Maigne, L.; Perrot, Y.; Schaart, D. R.; Donnarieix, D.; Breton, V.

    2011-02-01

    The GATE Monte Carlo simulation platform based on the GEANT4 toolkit has come into widespread use for simulating positron emission tomography (PET) and single photon emission computed tomography (SPECT) imaging devices. Here, we explore its use for calculating electron dose distributions in water. Mono-energetic electron dose point kernels and pencil beam kernels in water are calculated for different energies between 15 keV and 20 MeV by means of GATE 6.0, which makes use of the GEANT4 version 9.2 Standard Electromagnetic Physics Package. The results are compared to the well-validated codes EGSnrc and MCNP4C. It is shown that recent improvements made to the GEANT4/GATE software result in significantly better agreement with the other codes. We furthermore illustrate several issues of general interest to GATE and GEANT4 users who wish to perform accurate simulations involving electrons. Provided that the electron step size is sufficiently restricted, GATE 6.0 and EGSnrc dose point kernels are shown to agree to within less than 3% of the maximum dose between 50 keV and 4 MeV, while pencil beam kernels are found to agree to within less than 4% of the maximum dose between 15 keV and 20 MeV.

  20. Measurement of the x-ray mass attenuation coefficient and determination of the imaginary component of the atomic form factor of tin over the energy range of 29-60keV

    Microsoft Academic Search

    Martin D. de Jonge; Chanh Q. Tran; Christopher T. Chantler; Zwi Barnea; Bipin B. Dhal; David Paterson; Elliot P. Kanter; Stephen H. Southworth; Linda Young; Mark A. Beno; Jennifer A. Linton; Guy Jennings

    2007-01-01

    We use the x-ray extended-range technique (XERT) [C. T. Chantler , Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of tin in the x-ray energy range of 29-60keV to 0.04-3% accuracy, and typically in the range 0.1-0.2% . Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and

  1. Measurement of the x-ray mass attenuation coefficient and determination of the imaginary component of the atomic form factor of tin over the energy range of 29-60 keV

    Microsoft Academic Search

    Martin D. de Jonge; Chanh Q. Tran; Christopher T. Chantler; Zwi Barnea; Bipin B. Dhal; David Paterson; Elliot P. Kanter; Stephen H. Southworth; Linda Young; Mark A. Beno; Jennifer A. Linton; Guy Jennings

    2007-01-01

    We use the x-ray extended-range technique (XERT) [C. T. Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of tin in the x-ray energy range of 29-60 keV to 0.04-3 % accuracy, and typically in the range 0.1-0.2 %. Measurements made over an extended range of the measurement parameter space are critically examined to

  2. Measurement of the mass energy-absorption coefficient of air for x-rays in the range from 3 to 60 keV

    NASA Astrophysics Data System (ADS)

    Buhr, H.; Büermann, L.; Gerlach, M.; Krumrey, M.; Rabus, H.

    2012-12-01

    For the first time the absolute photon mass energy-absorption coefficient of air in the energy range of 10 to 60 keV has been measured with relative standard uncertainties below 1%, considerably smaller than those of up to 2% assumed for calculated data. For monochromatized synchrotron radiation from the electron storage ring BESSY II both the radiant power and the fraction of power deposited in dry air were measured using a cryogenic electrical substitution radiometer and a free air ionization chamber, respectively. The measured absorption coefficients were compared with state-of-the art calculations and showed an average deviation of 2% from calculations by Seltzer. However, they agree within 1% with data calculated earlier by Hubbell. In the course of this work, an improvement of the data analysis of a previous experimental determination of the mass energy-absorption coefficient of air in the range of 3 to 10 keV was found to be possible and corrected values of this preceding study are given.

  3. Measurement of the mass energy-absorption coefficient of air for x-rays in the range from 3 to 60 keV.

    PubMed

    Buhr, H; Büermann, L; Gerlach, M; Krumrey, M; Rabus, H

    2012-12-21

    For the first time the absolute photon mass energy-absorption coefficient of air in the energy range of 10 to 60 keV has been measured with relative standard uncertainties below 1%, considerably smaller than those of up to 2% assumed for calculated data. For monochromatized synchrotron radiation from the electron storage ring BESSY II both the radiant power and the fraction of power deposited in dry air were measured using a cryogenic electrical substitution radiometer and a free air ionization chamber, respectively. The measured absorption coefficients were compared with state-of-the art calculations and showed an average deviation of 2% from calculations by Seltzer. However, they agree within 1% with data calculated earlier by Hubbell. In the course of this work, an improvement of the data analysis of a previous experimental determination of the mass energy-absorption coefficient of air in the range of 3 to 10 keV was found to be possible and corrected values of this preceding study are given. PMID:23192280

  4. He+O{sup 2} collisions at low keV energies

    SciTech Connect

    Heckman, V.R.; Quintana, E.J.; Perry, D.M.; Pollack, E. [Univ. of Connecticut, Storrs, CT (United States)

    1996-05-01

    The direct scattering in He{sup 0}+O{sub 2} collisions is studied at low keV energies and scattering angles 0<{theta}<2 deg. Time-of-flight techniques are used to identify the states excited. The experimental techniques have previously been described. To date the authors have reported on H{sup 0}+N{sub 2} collisions and also on H{sup 0}+H{sub 2} and O{sub 2}. A striking characteristic of the H{sup 0} collisions is the weakness of the electronically elastic channel even at the smallest scattering angles. In He+O{sub 2} the authors find elastic scattering to be the dominant small angle process. The probability of electronically elastic scattering is greater than 0.5 at angles less than 1.0 deg and falls to 0.1 at 2.0 deg. The spectra show an inelastic peak at a 6 eV energy loss which is attributed to He+O{sub 2} {yields} He+O{sub 2}* {yields} He+O({sup 3}P) + O({sup 3}P). A broad structure with a maximum near 16 eV is seen at larger angles and is attributed in part to excitation resulting in dissociating states of O{sub 2}. Excitation of the He is found to be at the energies and angles studied. Additional results will be presented and interpreted.

  5. Study and implementation of a soft X-ray 100 eV -20 keV fixed exit monochromator system

    NASA Astrophysics Data System (ADS)

    Pelliciari, C.; Barbera, M.; Candia, R.; Collura, A.; Di Cicca, G.; Pareschi, G.; Varisco, S.

    2006-06-01

    We describe a "built in house" X-ray monochromator which produces a fixed exit X-ray beam tunable in the full energy range 0.1 - 20 keV. The system is based on a double diffraction on two large size parallel crystals positioned using a remotely controlled micropositioning system in order to keep the position of the monochromatic beam for any chosen energy. Up to six different diffracting elements can be selected without breaking the vacuum. This allows to cover the full energy range of interest. The system is part of an upgrading project of the XACT facility at the Istituto Nazionale di Astrofisica - Osservatorio Astronomico di Palermo G.S. Vaiana, and will be employed for the testing and calibration of filters, detectors and optics at X-ray wavelengths.

  6. Spectroscopy of Hard X-Rays (2 15 keV) Generated by Focusing Femtosecond Laser on Metal Targets

    Microsoft Academic Search

    Yasushi Fujimoto; Yoichiro Hironaka; Kazutaka G. Nakamura; Ken-ichi Kondo; Masatake Yoshida; Masayuki Ohtani; Hiroshi Tsunemi

    1999-01-01

    Spectroscopy of hard X-rays generated by focusing a femtosecond laser (42 fs at 780 nm) onto metal targets consisting elements of various atomic number (Z) is carried out in the energy range between 2 and 15 keV using a direct-detection charge-coupled-device camera.Sharp K-shell line emissions are observed for X-rays generated from medium-Z targets (Ti, Fe, Ni, Cu and Zn), which

  7. Design and fabrication of supermirrors for (2-10 keV) high resolution X-ray plasmas diagnostic imaging

    NASA Astrophysics Data System (ADS)

    Maury, H.; Bridou, F.; Troussel, Ph.; Meltchakov, E.; Delmotte, F.

    2010-09-01

    We have developed non-periodic W/SiC multilayer mirrors ("supermirrors") specifically designed to reflect photons between 2 and 10 keV. The mirrors were designed and optimized with a homemade calculation code. The supermirrors are designed to work at a nominal 0.7° grazing incidence with reflectivity above 35% in almost the entire energy range. The multilayers have been deposited by magnetron sputtering. Grazing incidence X-ray reflectance at 8 keV (0.154 nm) was made using a laboratory source. Reflectance measurement over the whole range was made at Physikalisch-Technische Bundesanstalt laboratory (PTB), the synchrotron radiation facility BESSY II, in Berlin. In addition to X-ray reflectance, multilayer thickness, refractive indices and roughness were characterized. The experimental results show good agreement with theoretical computations.

  8. Mu-2 ranging

    NASA Technical Reports Server (NTRS)

    Martin, W. L.; Zygielbaum, A. I.

    1977-01-01

    The Mu-II Dual-Channel Sequential Ranging System designed as a model for future Deep Space Network ranging equipment is described. A list of design objectives is followed by a theoretical explanation of the digital demodulation techniques first employed in this machine. Hardware and software implementation are discussed, together with the details relating to the construction of the device. Two appendixes are included relating to the programming and operation of this equipment to yield the maximum scientific data.

  9. Neutron capture resonances in /sup 56/Fe and /sup 58/Fe in the energy range from 10 to 100 keV

    SciTech Connect

    Kappeler, F.; Hong, L.D.; Wisshak, K.

    1983-07-01

    The neutron capture cross sections of /sup 56/Fe and /sup 58/Fe have been measured in the energy range from 10 to 250 keV relative to the gold standard. A pulsed 3-MV Van de Graaff accelerator and the /sup 7/Li(p,n) reaction served as a neutron source. Capture gamma rays were detected by two C/sub 6/D/sub 6/ detectors, which were operated in coincidence and anticoincidence modes. Two-dimensional data acquisition allowed the off-line application of the pulse height weighting technique. The samples were located at a 60-cm flight path. The total time resolution was 1.2 ns allowing an energy resolution of 2 ns/m. The experimental setup was optimized with respect to low background and low neutron sensitivity. The additional 4-cm flight path from the sample to the detector was sufficient to discriminate against the capture of sample scattered neutrons by the additional time of flight. In this way reliable results were obtained even for the strong s-wave resonances of both isotopes. The experimental capture yield was analyzed with the FANAC code. The energy resolution allowed extraction of resonance parameters in the energy range from 10 to 100 keV. Individual systematic uncertainties were found to range between 5 and 10% while the statistical uncertainty is 3 to 5% for most resonances. A comparison to other results exhibits systematic differences of 7 to 11% for /sup 56/Fe. The present results for /sup 58/Fe differ up to 50% from the only other measurement for this isotope.

  10. A Hard Medium Survey with the ASCA GIS: the (2-10 keV) Number Counts Relationship

    E-print Network

    Ilaria Cagnoni; Roberto Della Ceca; Tommaso Maccacaro

    1997-09-02

    In this paper we report the first results on a medium survey program conducted in the 2-10 keV energy band using data from the GIS2 instrument onboard the ASCA satellite. We have selected from the ASCA public archive (as of February 14, 1996) 87 images which are suitable for this project. 60 serendipitous X-ray sources, with a snr greater than 3.5, were found. The 2-10 keV flux of the detected sources ranges from 1.1e-13 erg/cm2/s to 4.1e-12 erg/cm2/s. Using this sample we have extended the description of the 2-10 keV LogN(>S)-LogS to a flux limit of ~6.3e-14 erg/cm2/s (the faintest detectable flux), i.e. about 2.7 orders of magnitude fainter than the Piccinotti et al. (1982) determination. The derived number-flux relationship is well described by a power law model, N(>S) = K S^{-a}, with best fit values a = 1.67 +- 0.18 and K = 2.85e-21 1/deg2. At the flux limit of the survey about 27% of the Cosmic X-ray Background in the 2-10 keV energy band is resolved in discrete sources. A flattening of the number-flux relationship, within a factor of 10 from the flux limit of the present survey, is expected in order to avoid saturation. The implications of these results on the models for the origin of the hard X-ray background are briefly discussed.

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

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

    The discovery in XMM-Newton X-ray data of X-ray emission above 2 keV 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 < 1 keV. We are presently exploring the relationship of this 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.

  12. 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.

    NASA Astrophysics Data System (ADS)

    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.

  13. Investigation of EBT2 and EBT3 films for proton dosimetry in the 4-20 MeV energy range.

    PubMed

    Reinhardt, S; Würl, M; Greubel, C; Humble, N; Wilkens, J J; Hillbrand, M; Mairani, A; Assmann, W; Parodi, K

    2015-03-01

    Radiochromic films such as Gafchromic EBT2 or EBT3 films are widely used for dose determination in radiation therapy because they offer a superior spatial resolution compared to any other digital dosimetric 2D detector array. The possibility to detect steep dose gradients is not only attractive for intensity-modulated radiation therapy with photons but also for intensity-modulated proton therapy. Their characteristic dose rate-independent response makes radiochromic films also attractive for dose determination in cell irradiation experiments using laser-driven ion accelerators, which are currently being investigated as future medical ion accelerators. However, when using these films in ion beams, the energy-dependent dose response in the vicinity of the Bragg peak has to be considered. In this work, the response of these films for low-energy protons is investigated. To allow for reproducible and background-free irradiation conditions, the films were exposed to mono-energetic protons from an electrostatic accelerator, in the 4-20 MeV energy range. For comparison, irradiation with clinical photons was also performed. It turned out that in general, EBT2 and EBT3 films show a comparable performance. For example, dose-response curves for photons and protons with energies as low as 11 MeV show almost no differences. However, corrections are required for proton energies below 11 MeV. Care has to be taken when correction factors are related to an average LET from depth-dose measurements, because only the dose-averaged LET yields similar results as obtained in mono-energetic measurements. PMID:25572031

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

    E-print Network

    S. Antier; O. Limousin; P. Ferrando

    2015-05-05

    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 principles and the results obtained for this kind of measurements: on one hand, we describe the simulation tool we have developed to predict the polarization performances in the 50-300 keV energy range. On the other hand, we compare simulation results with experimental data taken at ESRF ID15A (European Synchrotron Radiation Facility) using a mono-energetic polarized beam tuned between 35 and 300 keV. We show that it is possible with this detector to determine with high precision the polarization parameters (direction and fraction) for different irradiation conditions. Applying a judicious energy selection to our data set, we reach a remarkable sensitivity level characterized by an optimum Quality Factor of 0.78 in the 200-300 keV range. We also evaluate the sensitivity of our device at 70 keV, where hard X-ray mirrors are already available; the measured Q factor is 0.64 at 70 keV.

  15. Teflon impregnated anatase TiO2 nanoparticles irradiated by 80 keV Xe+ ions

    NASA Astrophysics Data System (ADS)

    Khanam, Rizwin; Paul, Nibedita; Kumar, P.; Kanjilal, D.; Ahmed, Gazi A.; Mohanta, Dambarudhar

    2014-10-01

    We report the effect of 80 keV Xe+ ion irradiation on the morphological and optical responses of TiO2 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 × 1017 ions/cm2, 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.

  16. Backscattering of He$sup +$ and H$sup +$ particles from ultra-thin films in the energy range 50--100 keV

    Microsoft Academic Search

    H. J. Goldberg; H. E. Jack; E. B. Dale

    1975-01-01

    Elastic collision cross sections of He$sup +$ and H$sup +$ ions incident ; on Au, Ag, Cu, Bi, Ni, and In, of density equivalent to less than a monolayer of ; target material, have been measured in the energy range 50--100 keV by the ; measurement of particles backscattered through a laboratory angle of 150degree. ; The results point to

  17. Interaction Potential between He+ and Ti in a keV Range as Revealed by a Specialized Technique in Ion Scattering Spectroscopy

    Microsoft Academic Search

    Masakazu Aono; Yinchun Hou; Ryutaro Souda; Chuhei Oshima; Shigeki Otani; Yoshio Ishizawa; Kyoji Matsuda; Ryuichi Shimizu

    1982-01-01

    The interaction potential between He+ and Ti in a keV range has been studied by a specialized technique in low-energy ion scattering spectroscopy. The interaction potential is described well by the Thomas-Fermi-Molière potential for the interaction between neutral He and Ti with a scaled screening radius.

  18. Gamma-Ray Burst Spectra and Time Histories from 2 to 400 keV

    E-print Network

    E. E. Fenimore

    1998-02-12

    The Gamma-Ray burst detector on Ginga consisted of a proportional counter to observe the x-rays and a scintillation counter to observe the gamma-rays. It was ideally suited to study the x-rays associated with gamma-ray bursts (GRBs). Ginga detected 120 GRBs and 22 of them had sufficient statistics to determine spectra from 2 to 400 keV. Although the Ginga and BATSE trigger criteria were very similar, the distribution of spectral parameters was different. Ginga observed bend energies in the spectra down to 2 keV and had a larger fraction of bursts with low energy power law indexes greater than zero. The average ratio of energy in the x-ray band (2 to 10 keV) compared to the gamma-ray band (50 to 300 keV) was 24%. Some events had more energy in the x-ray band than in the gamma-ray band. One Ginga event had a period of time preceding the gamma rays that was effectively pure x-ray emission. This x-ray ``preactivity'' might be due to the penchant for the GRB time structure to be broader at lower energy rather than a different physical process. The x-rays tend to rise and fall slower than the gamma rays but they both tend to peak at about the same time. This argues against models involving the injection of relativistic electrons that cool by synchrotron radiation.

  19. Omnibrowser 2.0

    NSDL National Science Digital Library

    With a nice set of customizable skins and sounds, Omnibrowser 2.0 is worth taking a look at. This new shell program provides a tabbed browser function, automatic popup blocking, and the internalized ability to consult major search engines. As with most similar programs, visitors can add favorite sites quickly, and also view a complete browser history. OmniBrowser 2.0 is compatible with all systems running Windows XP.

  20. Acceleration of 100 keV protons using a 5SDH2 Pelletron

    Microsoft Academic Search

    William A. Hollerman; Gary A. Glass; Nancy Ruzycki

    1999-01-01

    The authors successfully accelerated a 100keV proton beam using a model 5SDH-2 Pelletron accelerator, manufactured by National Electrostatics Corporation (NEC). A pseudo-stable 1–2nA beam was delivered on target with a net energy variation of less than 6%. However, the small terminal potential made it impossible to use standard stabilization techniques. Minor adjustments in terminal potential were required every 15min to

  1. Acceleration of 100keV protons using a 5SDH2 Pelletron

    Microsoft Academic Search

    W. A. Hollerman; G. A. Glass; N. Ruzycki

    1999-01-01

    The authors successfully accelerated a 100keV proton beam using a model 5SDH-2 Pelletron accelerator, manufactured by National Electrostatics Corporation (NEC). A pseudo-stable 1-2nA beam was delivered on target with a net energy variation of less than 6%. However, the small terminal potential made it impossible to use standard stabilization techniques. Minor adjustments in terminal potential were required every 15min to

  2. The EPIC/MOS view of the 2-8 keV Cosmic X-ray Background Spectrum

    E-print Network

    A. De Luca; S. Molendi

    2004-02-10

    We have measured the spectrum of the Cosmic X-ray Background (CXB) in the 2-8 keV range with the high throughput EPIC/MOS instrument onboard XMM-Newton. A large sample of high galactic latitude observations was used, covering a total solid angle of 5.5 square degrees. Our study is based on a very careful characterization and subtraction of the instrumental background, which is crucial for a robust measurement of the faintest diffuse source of the X-ray sky. The CXB spectrum is consistent with a power law having a photon index Gamma=1.41+/-0.06, with a 2-10 keV flux of (2.24+/-0.16)x10^(-11) erg/(cm^2 s deg) (90% confidence level, including the absolute flux calibration uncertainty). Our results are in excellent agreement with two of the most recent CXB measurements, performed with BeppoSAX LECS/MECS data (Vecchi et al. 1999) and with an independent analysis of XMM-Newton EPIC/MOS data (Lumb et al. 2002), providing a very strong constrain to the absolute sky surface brightness in this energy range, so far affected by a ~40% uncertainty. Our measurement immediately implies that the fraction of CXB resolved by the recent deep X-ray observations in the 2-10 keV band is of 80+/-7% (1 sigma), suggesting the existence of a new population of faint sources, largely undetected within the current sensitivity limits of the deepest X-ray surveys.

  3. Hot electron bolometer mixer for 20 - 40 THz frequency range

    NASA Astrophysics Data System (ADS)

    Finkel, M. I.; Maslennikov, S. N.; Vachtomin, Yu. B.; Svechnikov, S. I.; Smirnov, K. V.; Seleznev, V. A.; Korotetskaya, Yu. P.; Kaurova, N. S.; Voronov, B. M.; Gol'Tsman, G. N.

    2005-05-01

    The developed HEB mixer was based on a 5 nm thick NbN film deposited on a GaAs substrate. The active area of the film was patterned as a 30x20 square micron strip and coupled with a 50 ohm coplanar line deposited in situ. An extended hemispherical germanium lens was used to focus the LO radiation on the mixer. The responsivity of the mixer was measured in a direct detection mode in the 25-64 THz frequency range. The noise performance of the mixer and the directivity of the receiver were investigated in a heterodyne mode. A 10.6 micron wavelength CW CO2 laser was utilized as a local oscillator.

  4. Detection of interplanetary electrons from 18 keV to 1.8 MeV during solar quiet times, 1. On the origin of 200 KeV interplanetary electrons, 2.

    NASA Technical Reports Server (NTRS)

    Lin, R. P.; Anderson, K. A.; Cline, T. L.; Ramaty, R.; Fisk, L. A.

    1972-01-01

    A quiet time component of interplanetary electrons having energies above solar wind energies and below those characterized as cosmic radiation was observed. Its energy spectrum falls with energy from 18 keV to 1.8 MeV, but it shows a feature in the 100 to 300 keV range. The observed temporal variations of the intensity suggest that the 18 to 100 keV portion is solar and the 0.3 to 1.8 MeV portion is galactic in origin. Solar and terrestrial neutron decay electrons appear inadequate to explain the 100 to 300 keV feature.

  5. Quantum Efficiency Calibration of AXAF CCDs from 2 10 keV Herbert L. Manning, Stephen E. Jones, Steve E. Kissel,

    E-print Network

    the CCDs, providing a range of discrete emission lines to cover the energy band. A Si(Li) solid state.1­10 keV band. The MIT Center for Space Research, together with the MIT Lincoln Laboratory scientific focal plane instruments. 2 To unfold accurately the X­ray spectra of astrophysical sources

  6. Finite-Hilbert-basis-set calculations for the angular distribution of ionized electrons produced in p+H impact at 20 keV

    E-print Network

    Reading, John F.; Fu, J.; Fitzpatrick, M. J.

    2004-01-01

    We present a different method of extracting the angular distribution of ejected electrons in an ion-atom collision from a two-centered finite Hilbert basis-set calculation. We obtain good agreement with experiment for a p+H collision at 20 keV if we...

  7. Finite-Hilbert-basis-set calculations for the angular distribution of ionized electrons produced in p+H impact at 20 keV 

    E-print Network

    Reading, John F.; Fu, J.; Fitzpatrick, M. J.

    2004-01-01

    We present a different method of extracting the angular distribution of ejected electrons in an ion-atom collision from a two-centered finite Hilbert basis-set calculation. We obtain good agreement with experiment for a p+H collision at 20 keV if we...

  8. Marketing 2.0

    ERIC Educational Resources Information Center

    Germain, Carol Anne

    2008-01-01

    There is no doubt that today's student is much more savvy with using computers than the students of years gone by. This tech generation eagerly embraces the Internet, online searching, and the newer Web 2.0 technologies. This latter platform provides users with the ability to interact in a large virtual world, share/take (upload/download)…

  9. A multi-energy (2-60 keV) calibration of 200 ? m and 400 ?m diameter spectroscopic GaAs X-ray photodiodes

    NASA Astrophysics Data System (ADS)

    Barnett, A. M.; Lees, J. E.; Bassford, D. J.

    2013-09-01

    Thin (2 ?m active layer) spectroscopic p+-i-n+ GaAs X-ray photodiodes of circular mesa geometry (200 ?m and 400 ?m diameter; one representative diode of each diameter) have been characterised for their energy response using high-purity X-ray fluorescence calibration samples excited by an X-ray tube, giving energies between 2.1 keV (Au M?1) and 21.18 keV (Pd K?1), and an 241Am radioisotope ?-ray source (26.3 keV, 59.5 keV). The photodiodes were operated uncooled at +33°C. The 200 ?m diameter device's energy resolution (FWHM) was found to be constant (0.79 keV) and primarily limited by electronics noise at energies between 2.1 keV and 21.18 keV, but it broadened to 0.85 keV at 26.3 keV, and to 1 keV at 59.5 keV. The 400 ?m diameter device's energy resolution (FWHM) was constant (1.1 keV) for photon energies between 4.95 keV and 9.89 keV, but increased to 1.15 keV at 16.62 keV, 1.25 keV at 21.18 keV, 1.3 keV at 26.3 keV and 1.66 keV at 59.5 keV. The broadening of energy resolution (FWHM) observed in both cases is greater than can be attributed solely to increasing Fano noise and is hypothesised to be at least in part due to energy dependent charge trapping. However, for both types of device, the peak charge output from the devices was found to be linearly (R2 >= 0.9999) dependent on incident X-ray energy.

  10. A large scale height galactic component of the diffuse 2-60 keV background

    NASA Technical Reports Server (NTRS)

    Iwan, D.; Marshall, F. E.; Boldt, E. A.; Mushotzky, R.; Shafer, R. A.; Stottlemyer, A.

    1982-01-01

    The diffuse 2-60 keV X-ray background has a galactic component clearly detectable by its strong variation with both galactic latitude and longitude. This galactic component is typically 10 percent of the extragalactic background toward the galactic center, half that strong toward the anticenter, and extrapolated to a few percent of the extragalactic background toward the galactic poles. It is acceptably modeled by a finite radius emission disk with a scale height of several kiloparsecs. The averaged galactic spectrum is best fitted by a thermal spectrum of kT about 9 keV, a spectrum much softer than the about 40 keV spectrum of the extragalactic component. The most likely source of this emission is low luminosity stars with large scale heights such as subdwarfs. Inverse Compton emission from GeV electrons on the microwave background contributes only a fraction of the galactic component unless the local cosmic ray electron spectrum and intensity are atypical.

  11. Acceleration of 100 keV protons using a 5SDH-2 Pelletron

    NASA Astrophysics Data System (ADS)

    Hollerman, William A.; Glass, Gary A.; Ruzycki, Nancy

    1999-07-01

    The authors successfully accelerated a 100 keV proton beam using a model 5SDH-2 Pelletron accelerator, manufactured by National Electrostatics Corporation (NEC). A pseudo-stable 1-2 nA beam was delivered on target with a net energy variation of less than 6%. However, the small terminal potential made it impossible to use standard stabilization techniques. Minor adjustments in terminal potential were required every 15 min to maintain beam current and energy. This level of stability is sufficient to deliver a proton fluence of 10 11-10 12 cm -2 to any desired target.

  12. Copywrite 2.0

    NSDL National Science Digital Library

    In an effort to offer an alternative to various existing word processors and bundled office packages for home use, this new application offers a host of features designed to help writers working in a number of different styles and genres. Copywrite 2.0 features a flexible organization system, including an interface that allows writers to see how much progress they have made so far and, of course, inline spell checking, formatting, and a hyperlink feature as well. Copywrite 2.0 is free for small projects, while for larger projects individuals will have to purchase the product outright. This edition is compatible with all systems running Mac OS X 10.3 and higher.

  13. Electron capture in H{sup +} + O{sub 2} collisions at low keV energies

    SciTech Connect

    Quintana, E.J.; Heckman, V.R.; Pollack, E.

    1993-05-01

    Electron capture in H{sup +}{sub +}O{sub 2} is studied at low keV energies and scattering angles 0<{theta}<1 deg. Time-of-flight techniques are used to identify the states excited. Using the H{sup +}{sub +}H{sub 2} collisions as an energy reference our results to date show that at an energy E=1.0 keV the ground state, H(1s)+O{sub 2}{sup +}(X), channel is dominant only for {theta}<0.3 deg. At a scattering angle of 1.0 deg the probability for capture into the ground state is 0.3. This channel is exothermic by Q=-1.5 eV and is excited via a vertical transit on second important process resulting in H(1s)+O{sub 2}{sup +} also found at small scattering angles. Other-channels are seen at larger angles in the range investigated. Additional results will be presented and interpreted.

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

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Chowdhury, U.; Schulz, M.; Madison, D. H.

    2012-11-01

    We have calculated Triply differential cross sections (TDCS) and doubly differential cross sections (DDCS) for single ionization of H2 by 75 keV proton impact using the molecular 3 body distorted wave Eikonal initial state (M3DW-EIS) approach. Previously published measured DDCS-P (differential in the projectile scattering angle and integrated over the ejected electron angles) found pronounced structures at relatively large angles which were interpreted as an interference resulting from the two-centered potential of the molecule.

  16. Planetary 2.0

    NSDL National Science Digital Library

    Could there be a place where artists are stars? Albums are planets? Tracks are moons? Yes, yes, and yes. It is called Planetary 2.0 and it is a beautiful way to explore a music collection. Visitors can use this application with their music collection to create a series of wonderful visuals based on the planets, the stars, and various astronomical phenomena. Albums orbit around their artist star, the planet surface is derived from album cover art and the tracks are moons that orbit at a speed based on the length of the track. This version is compatible with all iPads running i0S 5.

  17. Oxide formation on aluminum in the presence of keV electrons and CO/sub 2/

    SciTech Connect

    Pitts, J.R.; Bischke, S.D.; Falconer, J.L.; Czanderna, A.W.

    1984-04-01

    Oxidation of aluminum by carbon dioxide at room temperature is significantly enhanced by an electron beam, and oxide growth is spatially restricted to the beam impact region. The growth of the oxide on aluminum films and sheets was studied with AES, XPS, ISS, and SIMS using isotopically labelled C/sup 18/O/sub 2/. XPS indicates that the oxide is similar to Al/sub 2/O/sub 3/ and that very little carbon accumulates on the surface. Both SIMS and ISS confirm that /sup 18/O is incorporated into the Al from C/sup 18/O/sub 2/. Residual gases and oxygen from the substrate are eliminated as possible oxygen sources for the oxidation. Beam heating is not a factor in enhancing the oxidation. Oxide islands were grown for a range of beam voltages (0.5--10 keV), beam current densities (0.8 mA/cm/sup 2/--7 A/cm/sup 2/) and CO/sub 2/ pressures (10/sup -6/--10/sup -4/ Pa). No CO/sub 2/ adsorption or Al oxidation was detected on a clean Al sheet in the absence of an electron beam. In the presence of the beam (2 keV, 7 A/cm/sup 2/), surface oxygen saturated after 5000 L (langmuir) CO/sub 2/ exposures. The mechanism for the oxide growth involves dissociation of the CO/sub 2/ into CO and O atoms in the region of electron beam impact on the surface. The oxygen atoms react with the Al to form the oxide and CO remains in the gas phase or desorbs.

  18. Sub-arcsec X-Ray Telescope for Imaging The Solar Corona In the 0.25 - 1.2 keV Band

    NASA Technical Reports Server (NTRS)

    Gallagher, Dennis; Cash, Webster; Jelsma, Schuyler; Farmer, Jason

    1996-01-01

    We have developed an X-ray telescope that uses a new technique for focusing X-rays with grazing incidence optics. The telescope was built with spherical optics for all of its components, utilizing the high quality surfaces obtainable when polishing spherical (as opposed to aspherical) optics. We tested the prototype X-ray telescope in the 300 meter vacuum pipe at White Sands Missile Range, NM. The telescope features 2 degee graze angles with tungsten coatings, yielding a bandpass of 0.25-1.5 keV with a peak effective area of 0.8 sq cm at 0.83 keV. Results from X-ray testing at energies of 0.25 keV and 0.93 keV (C-K and Cu-L) verify 0.5 arcsecond performance at 0.93 keV. Results from modeling the X-ray telescope's response to the Sun show that the current design would be capable of recording 10 half arcsecond images of a solar active region during a 300 second NASA sounding rocket flight.

  19. First mu+SR studies on thin films with a new beam of low energy positive muons at energies below 20 keV

    Microsoft Academic Search

    T. Prokscha; M. Birke; E. Forgan; H. Glückler; A. Hofer; T. Jackson; K. Küpfer; J. Litterst; E. Morenzoni; Ch. Niedermayer; M. Pleines; T. Riseman; A. Schatz; G. Schatz; H. P. Weber; C. Binns

    1999-01-01

    At the Paul Scherrer Institute slow positive muons (mu+) with nearly 100% polarization and an energy of about 10 eV are generated by moderation of an intense secondary beam of surface muons in an appropriate condensed gas layer. These epithermal muons are used as a source of a tertiary beam of tunable energy between 10 eV and 20 keV. The

  20. First ? + SR studies on thin films with a new beam of low energy positive muons at energies below 20 keV

    Microsoft Academic Search

    T. Prokscha; M. Birke; E. Forgan; H. Glückler; A. Hofer; T. Jackson; K. Küpfer; J. Litterst; E. Morenzoni; Ch. Niedermayer; M. Pleines; T. Riseman; A. Schatz; G. Schatz; H. P. Weber; C. Binns

    1999-01-01

    At the Paul Scherrer Institute slow positive muons (?+) with nearly 100% polarization and an energy of about 10 eV are generated by moderation of an intense secondary beam of surface\\u000a muons in an appropriate condensed gas layer. These epithermal muons are used as a source of a tertiary beam of tunable energy\\u000a between 10 eV and 20 keV. The

  1. Irradiation of water ices by 2 keV carbon ions

    NASA Astrophysics Data System (ADS)

    Hunniford, C. A.; Dawes, A.; Fulvio, D.; Sivaraman, B.; Merrigan, T. L.; McCullough, R. W.; Mason, N. J.; Palumbo, M. E.

    2009-04-01

    In this paper, we report on the results of experimental studies of the irradiation of pure water ices using 2 keV 13C+ and 13C2+ ions. Studies have been carried out at two temperatures (30 and 90 K) and the influence of the different morphologies at these temperatures has also been studied. With singly charged ions, the formation of 13CO2 was observed to be a strongly dependent upon morphology and showed a weaker dependence upon temperature. With doubly charged ions, the dependence upon temperature was significantly stronger. This is explained by enhanced production of reactive species resulting from the additional potential energy contained within the doubly charged ions. Increased temperature provides mobility to these species which may then yield additional 13CO2.

  2. Inferno 2.0

    NSDL National Science Digital Library

    Inferno, created at Lucent Technologies' Bell Labs, is a new operating system that could be the "Unix for the next century." Created by the same research lab that invented C++ and Unix, Inferno's primary goal is to operate seamlessly within a heterogeneous network environment. By abstracting resource interfaces to a common format, Inferno provides a general way to access all resources, both local and remote. Beyond that, the operating system is portable across many platforms and networks, and applications written in Limbo, the Inferno programming language, are also portable and lightweight. Impossible to describe in a single paragraph, the Inferno operating system is a fascinating leap ahead in networking and systems technology. Inferno is useful for research, development, learning, and many other possibilities. Freely available, Inferno 2.0 runs on Win95/NT, Solaris, and Linux.

  3. City 2.0

    NSDL National Science Digital Library

    2012-01-01

    TED's City 2.0 is "a gathering place for urban citizens to share innovations and inspire actions." The focus of this rather wonderful series of events was to work on envisioning the cities of the future. Visitors to the site will find archived videos from the devoted day of urban inspiration in 2012 and 2013 and they can click through the Videos area to get started. There are over two dozen talks here, including The Art of Data, Globalizing Home and Emerging from the Ecotone. Moving on to the People section, visitors can look over the stories shared from around the globe via the clickable map of the world. Visitors with a specific interest in a certain type of urban success story might want to use the Themes area to look over talks on art, housing, public space, or other matters.

  4. CO2 synthesis in solid CO by Lyman-? photons and 200 keV protons

    NASA Astrophysics Data System (ADS)

    Loeffler, M. J.; Baratta, G. A.; Palumbo, M. E.; Strazzulla, G.; Baragiola, R. A.

    2005-05-01

    We have studied the synthesis of carbon dioxide from solid carbon monoxide at 16 K induced by photolysis with Lyman-? photons and by irradiation with 200 keV protons to quantitatively compare the effects of photolysis and ion irradiation on CO ice and to determine the importance of these processes in interstellar ice grains. The CO and CO{2} concentrations during irradiation of an initially pure CO film evolve with fluence to a saturation value, a behaviour that is explained by a two-state model. Our results indicate that the initial CO{2} production rates for both radiation processes are similar when normalized to the absorbed energy and that the solid CO{2} abundance observed in the interstellar ices cannot be explained only by radiolysis and photolysis of pure solid CO.

  5. Differential cross sections for single ionization of H2 by 75-keV proton impact

    NASA Astrophysics Data System (ADS)

    Chowdhury, U.; Schulz, M.; Madison, D. H.

    2011-03-01

    We have calculated triply differential cross sections (TDCS) and doubly differential cross sections (DDCS) for single ionization of H2 by 75-keV proton impact using the molecular three-body distorted-wave-eikonal initial-state (M3DW-EIS) approach. Previously published measured DDCS (differential in the projectile scattering angle and integrated over the ejected electron angles) found pronounced structures at relatively large angles that were interpreted as an interference resulting from the two-centered potential of the molecule. Theory treating H2 as atomic H multiplied by a molecular interference factor only predicts the observed structure when assumptions are made about the molecular orientation. Here we apply the M3DW-EIS method, which does not rely on such an ad hoc approach, but rather treats the interference from first principles.

  6. Measurement of the x-ray mass attenuation coefficients of gold in the 38?50-keV energy range

    SciTech Connect

    Islam, M.T.; Rae, N.A.; Glover, J.L.; Barnea, Z.; de Jonge, M.D.; Tran, C.Q.; Wang, J.; Chantler, C.T. (Melbourne)

    2010-11-12

    We used synchrotron x rays to measure the x-ray mass attenuation coefficients of gold at nine energies from 38 to 50 keV with accuracies of 0.1%. Our results are much more accurate than previous measurements in this energy range. A comparison of our measurements with calculated mass attenuation coefficients shows that our measurements fall almost exactly midway between the XCOM and FFAST calculated theoretical values, which differ from one another in this energy region by about 4%, even though the range includes no absorption edge. The consistency and accuracy of these measurements open the way to investigations of the x-ray attenuation in the region of the L absorption edge of gold.

  7. Differential cross sections for scattering of 0. 5-, 1. 5-, and 5. 0-keV oxygen atoms by He, N sub 2 , and O sub 2

    SciTech Connect

    Schafer, D.A.; Newman, J.H.; Smith, K.A.; Stebbings, R.F. (Rice Univ., Houston, TX (United States))

    1987-06-01

    This paper reports measurements of absolute scattering cross sections, differential in angle, for collisions of ground state oxygen atoms with He, N{sub 2}, and O{sub 2}. Data are presented for scattering of 0.5-, 1.5-, and 5.0-keV oxygen atome projectiles in the range of laboratory frame angles between 0.06{degree} and 5{degree}. These measurements provide information relevant to calculations of the aeronomic consequences of O{sup +} precipitation in the earth's upper atmosphere.

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

    NASA Astrophysics Data System (ADS)

    Chowdhury, Uttam; Schulz, Michael; Madison, Don

    2011-05-01

    We have calculated Triply differential cross sections (TDCS) and doubly differential cross sections (DDCS) for single ionization of by 75 KeV proton impact using the molecular 3 body distorted wave Eikonal initial state (M3DW-EIS) approach. Previously published measured DDCS (differential in the projectile scattering angle and integrated over the ejected electron angles) found pronounced structures at relatively large angles which were interpreted as an interference resulting from the two-centered potential of the molecule. Theory treating H2 as atomic H multiplied by a molecular interference factor only predict the observed structure when assumptions are made about the molecular orientation. Here we apply the M3DW-EIS method, which does not rely on such an ad hoc approach, but rather treats the interference from first principles and we find the same structure without assuming any preferential orientations. We have calculated Triply differential cross sections (TDCS) and doubly differential cross sections (DDCS) for single ionization of by 75 KeV proton impact using the molecular 3 body distorted wave Eikonal initial state (M3DW-EIS) approach. Previously published measured DDCS (differential in the projectile scattering angle and integrated over the ejected electron angles) found pronounced structures at relatively large angles which were interpreted as an interference resulting from the two-centered potential of the molecule. Theory treating H2 as atomic H multiplied by a molecular interference factor only predict the observed structure when assumptions are made about the molecular orientation. Here we apply the M3DW-EIS method, which does not rely on such an ad hoc approach, but rather treats the interference from first principles and we find the same structure without assuming any preferential orientations. Work supported by the National Science Foundation under grant PHY-0757749

  9. Low Frequency QPOs from the Black Hole Candidate XTE J1550564 in the 2120 keV Range

    E-print Network

    Kalemci, Emrah

    transform of the time series (see Fig. 2). The dead­time depends on the energy loss in the scintillation for the dead­time effects in HEXTE power spectrum. We have been able to detect or obtain useful upper limits) features. The goal of this study is to test the dead­time correction technique and to use the resulting

  10. High-energy behavior of the double photoionization of helium from 2 to 12 keV

    NASA Astrophysics Data System (ADS)

    Levin, J. C.; Sellin, I. A.; Johnson, B. M.; Lindle, D. W.; Miller, R. D.; Berrah, N.; Azuma, Y.; Berry, H. G.; Lee, D.-H.

    1993-01-01

    We report the ratio of double-to-single photoionization of He at several photon energies from 2 to 12 keV. By time-of-flight methods, we find a ratio consistent with an asymptote at 1.5%+/-0.2%, essentially reached by h?~=4 keV. Fair agreement is obtained with older shake calculations of Byron and Joachain [Phys. Rev. 164, 1 (1967)], of Åberg [Phys. Rev. A 2, 1726 (1970)], and with recent many-body perturbation theory (MBPT) of Ishihara, Hino, and McGuire [Phys. Rev. A 44, 6980 (1991)]. The result lies below earlier MPBT calculations by Amusia et al. [J. Phys. B 8, 1248 (1975)] (2.3%), and well above semiempirical predictions of Samson [Phys. Rev. Lett. 65, 2861 (1990)], who expects no asymptote and predicts ?(He2+)/?(He+)=0.3% at 12 keV.

  11. Set-up of an XAFS beamline for measurements between 2.4-8 keV at DORIS III

    SciTech Connect

    Welter, Edmund [Deutsches Elektronen-Synchrotron A Research Centre of the Helmholtz Association, Notkestrasse 85, D-22607 Hamburg (Germany)

    2010-06-23

    In this paper results from the commissioning phase and from first user experiments of a new EXAFS beamline at the DORIS III storage ring are presented. The bending magnet EXAFS beamline A1 underwent a complete rebuild and now covers the energy range 2.4-8 keV. A Ni-coated toroidal mirror, placed in a 2:1 focusing position and a plane mirror with one Ni coated stripe and one uncoated (SiO{sub 2}) stripe are used for effective higher harmonics suppression and focusing. The UHV-compatible fixed-exit Double Crystal Monochromator (DCM) is equipped with two Si(111) crystal pairs. The second crystal of one of the two crystal pairs is tilted by 90 deg. around the surface normal to shift the position of glitches. It allows Bragg angles between 5 deg. and 55.5 deg. and continuous scans in quick-EXAFS mode. Test measurements during the commissioning phase proved the excellent performance of the monochromator and a high quality of the XAFS spectra over the entire working range.

  12. A NOVEL APPROACH TO MEASURE THE CROSS SECTION OF THE {sup 18}O(p, alpha){sup 15}N RESONANT REACTION IN THE 0-200 keV ENERGY RANGE

    SciTech Connect

    La Cognata, M.; Spitaleri, C.; Cherubini, S.; Crucilla, V.; Gulino, M.; Lamia, L.; Pizzone, R. G.; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S.; Sergi, M. L. [INFN - Laboratori Nazionali del Sud and DMFCI - Universita di Catania, Catania (Italy); Mukhamedzhanov, A.; Banu, A.; Goldberg, V.; Tabacaru, G.; Trache, L. [Cyclotron Institute - Texas A and M University, College Station, TX (United States); Coc, A. [CSNSM CNRS/IN2P3, Universite Paris Sud, Orsay (France); Irgaziev, B. [GIK - Institute of Engineering Sciences and Technology, Topi District, Swabi NWFP (Pakistan); Kiss, G. G. [ATOMKI, Debrecen (Hungary); Mrazek, J., E-mail: Spitaleri@lns.infn.i [Nuclear Physics Institute of ASCR, Rez (Czech Republic)

    2010-01-01

    The {sup 18}O(p, alpha){sup 15}N reaction is of primary importance to pin down the uncertainties, due to nuclear physics input, affecting present-day models of asymptotic giant branch stars. Its reaction rate can modify both fluorine nucleosynthesis inside such stars and oxygen and nitrogen isotopic ratios, which allow one to constrain the proposed astrophysical scenarios. Thus, an indirect measurement of the low-energy region of the {sup 18}O(p, alpha){sup 15}N reaction has been performed to access, for the first time, the range of relevance for astrophysical application. In particular, a full, high-accuracy spectroscopic study of the 20 and 90 keV resonances has been performed and the strengths deduced to evaluate the reaction rate and the consequences for astrophysics.

  13. Optimizing 9-25 keV point projection 2D backlighters

    NASA Astrophysics Data System (ADS)

    Baker, Kevin; MacLaren, Steve; Glendinning, Gail; Seugling, Richard; Whiting, Nick; Source, Chuck; Fooks, Julie; Fournier, Kevin; Biener, Monika; Martinez, David; Smalyuk, Vladimir; Dittrich, Tom; Moore, Alastair; Guymer, Tom

    2013-10-01

    The conversion efficiency of zinc He? backlighter and silver k? sources have been studied on the OMEGA laser. A common platform was used to evaluate the conversion efficiency from Zn foils with and without a 2.8 ns prepulse and from low density zinc foams containing varying quantities of zinc relative to low Z foam constituents. The common platform consisted of a 2 mm diameter by 2 mm long tube that was either filled with a low density foam or had two foils glued on the ends of an empty tube. The foam targets, which underwent volume ionization, exhibited more uniform radial emission above 1 keV than the foil targets. The thinnest Zn exploding foil targets stagnated in the middle of the tube producing a temporally longer He? emission than the other targets. The highest overall conversion efficiency came from a foil target driven with a 2.8 ns prepulse. Initial results from silver k? sources will also be presented.

  14. Measurement of the 20 and 90 keV resonances in the 18O(p,alpha)15N reaction via the Trojan horse method.

    PubMed

    La Cognata, M; Spitaleri, C; Mukhamedzhanov, A M; Irgaziev, B; Tribble, R E; Banu, A; Cherubini, S; Coc, A; Crucillà, V; Goldberg, V Z; Gulino, M; Kiss, G G; Lamia, L; Mrazek, J; Pizzone, R G; Puglia, S M R; Rapisarda, G G; Romano, S; Sergi, M L; Tabacaru, G; Trache, L; Trzaska, W; Tumino, A

    2008-10-10

    The 18O(p,alpha)15N reaction is of primary importance in several astrophysical scenarios, including fluorine nucleosynthesis inside asymptotic giant branch stars as well as oxygen and nitrogen isotopic ratios in meteorite grains. Thus the indirect measurement of the low energy region of the 18O(p,alpha)15N reaction has been performed to reduce the nuclear uncertainty on theoretical predictions. In particular the strength of the 20 and 90 keV resonances has been deduced and the change in the reaction rate evaluated. PMID:18999593

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

    NASA Technical Reports Server (NTRS)

    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.

  16. Magnetic short-range correlations and quantum critical scattering in the non-Fermi liquid regime of URu2-xRexSi2 (x=0.20.6)

    E-print Network

    Aronson, Meigan

    of uranium ions in the non-Fermi liquid compounds URu2-xRexSi2, for x=0.2 to 0.6, have been investigated.024413 PACS number s : 71.10.Hf, 71.20.Eh, 73.43.Nq, 78.70.Nx I. INTRODUCTION The order parameters

  17. Experimentally determined density matrices for H( n =3) formed in H sup + -He collisions from 20 to 100 keV

    SciTech Connect

    Ashburn, J.R.; Cline, R.A.; van der Burgt, P.J.M.; Westerveld, W.B.; Risley, J.S. (Atomic Collisions Laboratory, Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202 (US))

    1990-03-01

    Density matrices describing H({ital n}=3) atoms produced in collisions of 20- to 100-keV protons with He atoms have been determined experimentally. In the experiment the intensity and polarization of Balmer-{alpha} radiation emitted from a He gas cell are measured as a function of the strength of an externally applied electric field. Electric fields are applied in a direction either axial to or transverse to the proton beam. Density matrices are extracted by detailed analysis of the optical data. Data are obtained for each field direction and then analyzed, separately and in combination, to yield density matrices. Satisfactory agreement is found between density matrices determined from axial and transverse electric field data except at the lowest energies studied. Some nonzero density-matrix elements are determined more accurately using axial electric fields than with transverse fields, while other elements are more accurately determined using transverse electric fields. The combined analysis using data from both field directions gives a better determination of the density matrix than the separate data sets. Results for the H({ital n}=3) electron-transfer cross sections (relative to 3{ital s}), the electric dipole moment of the charge distribution {l angle}{bold d}{r angle}{sub {ital z}}, a first-order moment of the current distribution {l angle}{bold L}{times}{bold A}{r angle}{sub {ital z},{ital s}}, and the average coherence Tr({sigma}{sub 3}{sup 2}) are obtained. The experimental results are compared to two recent calculations using the augmented atomic orbital (AO+) theory and the continuum distorted-wave approximation with post-collision interaction theory, and to one recent experimental measurement of the diagonal density-matrix elements. Both theories show qualitative agreement with the general trends in the data. The AO+ method gives better quantitative agreement.

  18. Understanding Web 2.0

    Microsoft Academic Search

    San Murugesan

    2007-01-01

    Web 2.0, the second phase in the Web's evolution, is attracting the attention of IT professionals, businesses, and Web users. Web 2.0 is also called the wisdom Web, people-centric Web, participative Web, and read\\/write Web. Web 2.0 harnesses the Web in a more interactive and collaborative manner, emphasizing peers' social interaction and collective intelligence, and presents new opportunities for leveraging

  19. THEORIZING WEB 2.0

    Microsoft Academic Search

    Felicia Wu Song

    2010-01-01

    This article explores the conceptual problems surrounding popular definitions of Web 2.0 and proposes an alternative approach to understanding the cultural dimension of Web 2.0. Drawing parallels between the discursive and analytical challenges of Web 2.0 and online communities, this article suggests that a theoretical framework, based on Bourdieu's theory of field and habitus, can be applied to theorizing Web

  20. News 2.0

    Microsoft Academic Search

    John Stanik

    2005-01-01

    You’ve watched in awe as spyware programs cannibalized each other, shookyour head in disgust when that vigilante, anti-piracy P2P virus deleted all ofyour MP3s, and felt instant paranoia after learning about the astonishing numberof zombie PCs out there (“could I be a zombie?”). Well, it just keepsgetting weirder... and scarier.

  1. Library Instruction 2.0

    ERIC Educational Resources Information Center

    Bridgewater, Rachel; Deitering, Anne-Marie; Munro, Karen

    2009-01-01

    At the 2008 ALA Annual Conference, a wonderful Association of College and Research Libraries (ACRL) preconference was presented entitled "Library Instruction 2.0: Building Your Online Instruction Toolkit". The presentation was enlightening and provided numerous and valuable recommendations for Web 2.0 sites that can facilitate and enliven library…

  2. Web 2.0, Library 2.0, and Librarian 2.0:Preparing for the 2.0 World

    NASA Astrophysics Data System (ADS)

    Abram, S.

    2007-10-01

    There is a global conversation going on right now about the next generation of the web. It's happening under the name of Web 2.0. It's the McLuhanesque hot web where true human interaction takes precedence over merely `cool' information delivery and e-mail. It's about putting information into the real context of our users' lives, research, work and play. Concurrently, a group of information professionals are having a conversation about the vision for what Library 2.0 will look like in this Web 2.0 ecosystem. Some are even going so far as to talk about Web 3.0! Web 2.0 is coming fast and it's BIG! What are the skills and competencies that Librarian 2.0 will need? Come and hear an overview of Web 2.0 and a draft vision for Library 2.0 and an opinion about what adaptations we'll need to make to thrive in this future scenario. Let's talk about the Librarian 2.0 in our users' future!

  3. BASINS 2.0

    NSDL National Science Digital Library

    1998-01-01

    The Environmental Protection Agency (EPA) first created BASINS (Better Assessment Science Integrating Point and Nonpoint Sources) in 1996 as an aid to water resource planners concerned with water quality and watershed analyses. The strength of BASINS is its integration of "a geographic information system (GIS), national watershed data, and state-of-the-art environmental assessment and modeling tools." The updated version of the program, BASINS 2, can be downloaded from this site.

  4. -/20-2-2009 -/20-2-2009

    E-print Network

    ;-/20-2-2009 µ µ µ (first wall) µ MCNP SiCf/SiC µ µ µµ µ Nucl. Instr. Meth B, 2005 4 D T He n -8 10 -5 10 -2 10 1 10 4 10 7 this work Forest pure SiCf /SiC DoseRate(Sv/h) Time (years) Hands;-/20-2-2009 µ µ µ Sample Detector Shield Collimated transmission source shieldHPGe Detector 210 240 270 300 10

  5. Measurement of the x-ray mass attenuation coefficient and determination of the imaginary component of the atomic form factor of tin over the energy range of 29-60keV

    NASA Astrophysics Data System (ADS)

    de Jonge, Martin D.; Tran, Chanh Q.; Chantler, Christopher T.; Barnea, Zwi; Dhal, Bipin B.; Paterson, David; Kanter, Elliot P.; Southworth, Stephen H.; Young, Linda; Beno, Mark A.; Linton, Jennifer A.; Jennings, Guy

    2007-03-01

    We use the x-ray extended-range technique (XERT) [C. T. Chantler , Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of tin in the x-ray energy range of 29-60keV to 0.04-3% accuracy, and typically in the range 0.1-0.2% . Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct a number of potential experimental systematic errors. These results represent the most extensive experimental data set for tin and include absolute mass attenuation coefficients in the regions of x-ray absorption fine structure, extended x-ray absorption fine structure, and x-ray absorption near-edge structure. The imaginary component of the atomic form factor f2 is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-2% persist between calculated and observed values.

  6. Measurement of the x-ray mass attenuation coefficient and determination of the imaginary component of the atomic form factor of tin over the energy range of 29-60 keV

    SciTech Connect

    Jonge, Martin D. de; Tran, Chanh Q.; Chantler, Christopher T.; Barnea, Zwi; Dhal, Bipin B.; Paterson, David; Kanter, Elliot P.; Southworth, Stephen H.; Young, Linda; Beno, Mark A.; Linton, Jennifer A.; Jennings, Guy [X-Ray Operations and Research, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States); School of Physics, University of Melbourne, Victoria 3010 (Australia); Australian Synchrotron Project, Major Projects Victoria, 800 Blackburn Road, Clayton, Victoria 3168 (Australia); Chemistry Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States); BESSRC-CAT, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439 (United States)

    2007-03-15

    We use the x-ray extended-range technique (XERT) [C. T. Chantler et al., Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of tin in the x-ray energy range of 29-60 keV to 0.04-3 % accuracy, and typically in the range 0.1-0.2 %. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct a number of potential experimental systematic errors. These results represent the most extensive experimental data set for tin and include absolute mass attenuation coefficients in the regions of x-ray absorption fine structure, extended x-ray absorption fine structure, and x-ray absorption near-edge structure. The imaginary component of the atomic form factor f{sub 2} is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-2 % persist between calculated and observed values.

  7. Total bremsstrahlung spectral photon distributions in metallic targets in the photon energy range of 5–10 keV by 204Tl beta particles

    Microsoft Academic Search

    Tajinder Singh; K. S. Kahlon; A. S. Dhaliwal

    2009-01-01

    Total bremsstrahlung spectral photon distributions produced by beta particles of the 204Tl beta emitter in thick targets of Al, Ti, Sn and Pb targets were evaluated at photon energies from 5keV to 10keV. Experimental measurements were compared with the theoretical total bremsstrahlung spectral photon distributions obtained from Elwert corrected (non-relativistic) Bethe–Heitler theory and modified Elwert factor (relativistic) Bethe–Heitler theories for

  8. Total bremsstrahlung spectral photon distributions in metallic targets in the photon energy range of 5-10 keV by 204Tl beta particles

    Microsoft Academic Search

    Tajinder Singh; K. S. Kahlon; A. S. Dhaliwal

    2009-01-01

    Total bremsstrahlung spectral photon distributions produced by beta particles of the 204Tl beta emitter in thick targets of Al, Ti, Sn and Pb targets were evaluated at photon energies from 5 keV to 10 keV. Experimental measurements were compared with the theoretical total bremsstrahlung spectral photon distributions obtained from Elwert corrected (non-relativistic) Bethe-Heitler theory and modified Elwert factor (relativistic) Bethe-Heitler

  9. Extraction system design for 50A, 50keV, 2 sec ion beam

    Microsoft Academic Search

    L. D. Stewart; R. C. Davis; T. C. Jernigan; O. B. Morgan; D. E. Schechter; W. L. Stirling

    1974-01-01

    The basic ORMAK injection unit was operated at 40 keV, 6A, 0.3 sec and a 15% duty cycle, while monitoring power loading to the various extraction system electrodes, in order to pinpoint the critical power loading areas. A 40A scaleup of this ORMAK unit is being built. Thermal time constants for these water-cooled extraction electrodes are about 0.5 sec. Going

  10. Mid-crust fluid and water-rock interaction kinetic experiments and their geophysical significance: 2. syenite-water interaction in the temperature range from 20 to 435°C

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Zhang, R.; Hu, S.

    2013-12-01

    The kinetics Experiments on syenite-water interactions were carried out in a horizontally-mounted packed bed reactor in the temperature range from 20 to 435°C and at pressures of 23-36 MPa. The net dissolution rates (mol/minute/m2 or mol/s/m2) normalized to their specific surface area (A) are calculated using the following expression: -r = (Ci - C0) / [t (A/V) ?i] where Ci is the output concentration of species i, C0 is the initial concentration of species i, A is the total reactive surface area of the mineral (m2), t is the average fluid residence time, and V is the volume of the pressure vessel (mL), i.e., liquid volume. ?i is the stoichiometric coefficient of the ith element in the mineral formula (Zhang R.H. et al., 2000). Thus, the dissolution rates of syenite in water and the electric conductance can be measured simultaneously at temperature from 20 to 435°C and at pressure from 23-36MPa. The results indicated that the release rates of Si, Al, K and Na of the syenite increase with increasing temperature, and reached maximum values at 400°C. The release rates of Ca, Mg reached maximum values at 200°C. The release rates of Fe reached maximum values at 374°C. Another important impact factor of the reaction between syenite and water is pressure. The release rates of Si did not vary with pressure, as pressure was changed from 23 to 36 MPa. The release rates of K and Al in syenite increase with increasing pressure. The maximum release rates (rM) of Ni and Cu are reached at 300°C, 23 MPa, and the rM (Zn) is at 374°C, 23MPa. But the rM (Mn) is reached at low temperature (25°C) and 31MPa. The rM (Sr) and rM (Ba) are present at low temperature (20-200°C) and 23 MPa, The rM (Mo) is at 350°C and 23 MPa. The rM of Pb is present at 400°C, 23 MPa. The most metals (Si, Ca and ore-forming elements) easily release into aqueous solutions at 23 MPa. If increasing pressure from 23 to 36 MPa, most molar concentration ratio of metal Mi vs Si, Mi/MSi in the effluent solutions decreases with pressure. The in situ measurements of electric conductances of the water-rock interaction system at temperature range from 20-435°C, 23-36MPa were performed using the flow system. The in situ measurements of electric conductances combined the kinetic experiments found that the maximum electric conductances are present at 374-390°C, 23-36MPa, and simultaneously the maximum release rates of Si, Al, K are reached at the same temperature range. These results provide useful information for estimating the behavior of crustal fluids and the geophysical nature of the mid-crust. Note: These studies reported here have been supported by the Ministry of Land and Resources and the Ministry of Science and Technology: k[2013]01-062-014, SinoProbe-07-02-03, SinoProbe-03-01-2A, 20010302 and project of Anhui Province (2010G28). Key words: chemical kinetics, critical state, syenite-water interaction, electric conductance, high conductivity zone, high temperature experiment.

  11. Ionic fragmentation of CO and H2O under impact of 10 keV electrons: kinetic energy release distributions

    NASA Astrophysics Data System (ADS)

    Singh, Raj; Bhatt, Pragya; Yadav, Namita; Shanker, R.

    2014-04-01

    Dissociative ionization of COq+ (q=2-4) and H2Oq+ (q=2-3) molecular ions produced from the collisions of CO and H2O with 10 keV electrons is studied using time-of-flight mass spectrometer and position sensitive detector with multi-hit ability, respectively. The kinetic energy release distributions for these channels are obtained. We found that a pure Coulomb explosion model is insufficient to explain the observed kinetic release distributions for the Coulomb explosion channels. A detail of this study is given in references [3, 4].

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

    SciTech Connect

    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.

  13. Neutron inelastic scattering cross sections for states above 700 keV in /sup 232/Th

    SciTech Connect

    Ciarcia, C.A.; Couchell, G.P.; Egan, J.J.; Kegel, G.H.R.; Li, S.Q.; Mittler, A.; Pullen, D.J.; Schier, W.A.; Shao, J.Q.

    1985-12-01

    Fast neutron inelastic scattering cross sections for levels between 700- and 1400-keV excitation energy in /sup 232/Th have been measured using the (n,n') time-of-flight (TOF) technique. Measurements of 125-deg differential cross sections were made using neutrons with a typical energy spread of 8 to 10 keV, generated by the /sup 7/Li(p,n)/sup 7/ Be reaction. The incident neutron energies covere three regions: (a) 950 to 1550 keV in 50-keV intervals with the TOF spectrometer optimized to detect 200 to 600-keV scattered neutrons, (b) 1200 to 2000 keV in 100-keV intervals with the spectrometer optimized to detect 400- to 800-keV scattered neutrons, and (c) 1700 to 2100 keV in 100-keV steps with the spectrometer optimized for 800- to 1300-keV scattered neutrons. Throughout the experiment, an overall energy resolution of <15 keV was maintained. Level cross sections were deduced from the 125-deg differential scattering cross sections and are compared with (n,n'..gamma..) measurements and the ENDF/B-V evaluation. Angular distributions for states in the 700- to 900-keV region have been measured at 1.2, 1.5, and 2.0 MeV.

  14. Measurement of the x-ray mass attenuation coefficient and determination of the imaginary component of the atomic form factor of molybdenum over the 13.5-41.5-keV energy range

    NASA Astrophysics Data System (ADS)

    de Jonge, Martin D.; Tran, Chanh Q.; Chantler, Christopher T.; Barnea, Zwi; Dhal, Bipin B.; Cookson, David J.; Lee, Wah-Keat; Mashayekhi, Ali

    2005-03-01

    We use the x-ray extended-range technique (XERT) [Chantler , Phys. Rev. A 64, 062506 (2001)] to measure the mass attenuation coefficients of molybdenum in the x-ray energy range of 13.5-41.5keV to 0.02-0.15 % accuracy. Measurements made over an extended range of the measurement parameter space are critically examined to identify, quantify, and correct where necessary a number of experimental systematic errors. These results represent the most extensive experimental data set for molybdenum and include absolute mass attenuation coefficients in the regions of the x-ray absorption fine structure (XAFS) and x-ray-absorption near-edge structure (XANES). The imaginary component of the atomic form-factor f2 is derived from the photoelectric absorption after subtracting calculated Rayleigh and Compton scattering cross sections from the total attenuation. Comparison of the result with tabulations of calculated photoelectric absorption coefficients indicates that differences of 1-15 % persist between the calculated and observed values.

  15. LETTER TO THE EDITOR: Quantum efficiency measurements of an uncoated CEM in the range 0.14 - 160 nm (9 keV - 8 eV)

    NASA Astrophysics Data System (ADS)

    Boscolo, A.; Placentino, L.; Poletto, L.

    1998-07-01

    The quantum efficiency of an uncoated channel electron multiplier (CEM) working in the photon-counting regime has been evaluated over a wide spectral range, which comprises the EUV and soft x-ray regions. Three different experimental set-ups have been used: a Johnson - Onaka monochromator for the 30 - 160 nm region, a grazing incidence monochromator for the 0.3 - 30 nm region and a test facility mounting filters for the 0.14 - 0.3 nm region. As a secondary standard, both silicon and aluminium photodiodes have been used. The efficiency has been evaluated at normal incidence angle. The measured values range from 2% to 15% in the range 0.14 - 100 nm, while a rapid decrease is present over 120 nm. Changes in the efficiency due to carbon contamination in the vacuum system are discussed, and also effects due to variations of the illuminated area on the CEM entrance cone.

  16. Do the O2 Schumann-Runge bands participate in keV collision-induced dissociation experiments?

    PubMed

    Lin, Yawei; Mayer, Paul M

    2011-01-01

    In high-energy (keV) CID experiments, oxygen has the unique ability to enhance specific ion fragmentation pathways that lie within a relatively narrow band of activation energy. It has been previously proposed that this oxygen-enhanced dissociation phenomenon is due to the participation of the O(2) B(3)?(u)(+) - X(3)?(g)(-) (Schumann-Runge) system in the collision complex. During the collision, oxygen is first excited to its [Formula: see text] state before it returns this energy to the projectile ion. This energy drives the nonstatistical dissociation of the projectile provided there is an energetically accessible pathway in resonance with the absorbed radiation. To probe the validity of this hypothesis, a modified VG-ZAB mass spectrometer was used to observe the photon emissions from keV collisions of a selection of projectile ions with O(2) target gas. By studying the resulting collision-induced emission (CIE) spectra, a second potential mechanism came to light, one that involves the near-isoenergetic O(2) (+.) A (2)?(u)?X (2) ?(g) state transition. PMID:21472546

  17. Indie Toolbar 2.0

    NSDL National Science Digital Library

    Developed by Alexander Wilson, this handy little application allows users to create a customizable standalone internet toolbar. This latest version also contains a host of new icons, bringing the total that may be used to over 300. The icons themselves are divided into a number of different themes such as those related to Macs, and those representing the Web sites of different nonprofit organizations. The Web site for Indie Toolbar 2.0 also features several screen shots and an area where users can send bug reports to Mr. Wilson directly. Indie Toolbar 2.0 is compatible with all systems running Mac OS X 10.1 and higher or Windows 95 and higher.

  18. Autogen Version 2.0

    NASA Technical Reports Server (NTRS)

    Gladden, Roy

    2007-01-01

    Version 2.0 of the autogen software has been released. "Autogen" (automated sequence generation) signifies both a process and software used to implement the process of automated generation of sequences of commands in a standard format for uplink to spacecraft. Autogen requires fewer workers than are needed for older manual sequence-generation processes and reduces sequence-generation times from weeks to minutes.

  19. Variations of the Solar Flux in the 1 to 50 nm Range Over a Solar Rotation Inferred From Observations of Photoelectrons With Energies From 0.01 to 1 keV From the FAST Satellite

    Microsoft Academic Search

    W. Peterson; P. Chamberlin; T. Woods; P. Richards

    2006-01-01

    We have analyzed one minute average photoelectron energy spectra from 10 eV to 1 keV observed at ~ 3,000 km, equatorward of the auroral oval for the July-August, 2002 Solar rotation. Variations in these photoelectron spectra arise primarily from variations in the Solar flux in the 1 to 50 nm range and to a lesser extent changes in the composition

  20. Measurement of X-ray mass attenuation coefficients in biological and geological samples in the energy range of 7-12keV.

    PubMed

    Trunova, Valentina; Sidorina, Anna; Kriventsov, Vladimir

    2014-10-17

    Information about X-ray mass attenuation coefficients in different materials is necessary for accurate X-ray fluorescent analysis. The X-ray mass attenuation coefficients for energy of 7-12keV were measured in biological (Mussel and Oyster tissues, blood, hair, liver, and Cabbage leaves) and geological (Baikal sludge, soil, and Alaskite granite) samples. The measurements were carried out at the EXAFS Station of Siberian Synchrotron Radiation Center (VEPP-3). Obtained experimental mass attenuation coefficients were compared with theoretical values calculated for some samples. PMID:25464176

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

    NASA Astrophysics Data System (ADS)

    Gowda, Shivalinge; Krishnaveni, S.; Gowda, Ramakrishna

    2005-10-01

    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.

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

    E-print Network

    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. POP Peeper 2.0

    NSDL National Science Digital Library

    2002-01-01

    Supported by all Windows operating systems, POP Peeper 2.0 is a small utility that resides in your Windows task bar and informs users when they have new email from any of their POP3, MSN, Yahoo, or Hotmail accounts. Additionally, the POP Peeper supports HTML email. Finally, the utility allows users to be notified of new email from any of these accounts with a visual or audial reminder. The POP Peeper Web site also has a handy FAQ section that addresses problems or questions users might have.

  4. Energy loss distribution of 100 keV H+ in thin carbon films

    Microsoft Academic Search

    Noriaki Matsunami; Kenshin Kitoh

    1992-01-01

    The energy loss of ~100 keV H+ transmitted through thin carbon films of thickness in the range 6-20 nm has been measured with an energy resolution of ~ 20 eV. We have observed new energy loss peaks around 210 and 400 eV in addition to the normal energy loss peak around 1 keV for the thinner film of ~ 7

  5. Herwig++ 2.0 Release Note.

    E-print Network

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

    program [10]. This model allows the forced branchings to take place between a scale QSpac (Default 2.5 GeV) and a multiple EmissionRange (Default 1.1) of the minimum scale. The energy fractions are then determined using the perturbative result... ar X iv :h ep -p h/ 06 09 30 6v 1 2 9 Se p 20 06 Cavendish-HEP-06/18 CERN-PH-TH/2006-182 IFJPAN-IV-2006-6 IPPP/06/55 KA-TP-10-2006 September 2006 Herwig++ 2.0 Release Note S. Gieseke Institut fu¨r Theoretische Physik, Universita¨t Karlsruhe E...

  6. Differential cross sections for single ionization of H{sub 2} by 75-keV proton impact

    SciTech Connect

    Chowdhury, U.; Schulz, M.; Madison, D. H. [Missouri University of Science and Technology, Department of Physics and Laboratory for Atomic, Molecular, and Optical Research, Rolla, Missouri 65401 (United States)

    2011-03-15

    We have calculated triply differential cross sections (TDCS) and doubly differential cross sections (DDCS) for single ionization of H{sub 2} by 75-keV proton impact using the molecular three-body distorted-wave-eikonal initial-state (M3DW-EIS) approach. Previously published measured DDCS (differential in the projectile scattering angle and integrated over the ejected electron angles) found pronounced structures at relatively large angles that were interpreted as an interference resulting from the two-centered potential of the molecule. Theory treating H{sub 2} as atomic H multiplied by a molecular interference factor only predicts the observed structure when assumptions are made about the molecular orientation. Here we apply the M3DW-EIS method, which does not rely on such an ad hoc approach, but rather treats the interference from first principles.

  7. The PLATO 2.0 mission

    NASA Astrophysics Data System (ADS)

    Rauer, H.; Catala, C.; Aerts, C.; Appourchaux, T.; Benz, W.; Brandeker, A.; Christensen-Dalsgaard, J.; Deleuil, M.; Gizon, L.; Goupil, M.-J.; Güdel, M.; Janot-Pacheco, E.; Mas-Hesse, M.; Pagano, I.; Piotto, G.; Pollacco, D.; Santos, ?.; Smith, A.; Suárez, J.-C.; Szabó, R.; Udry, S.; Adibekyan, V.; Alibert, Y.; Almenara, J.-M.; Amaro-Seoane, P.; Eiff, M. Ammler-von; Asplund, M.; Antonello, E.; Barnes, S.; Baudin, F.; Belkacem, K.; Bergemann, M.; Bihain, G.; Birch, A. C.; Bonfils, X.; 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.; Church, R. P.; Csizmadia, Sz.; Cunha, M.; Damasso, M.; Davies, M. B.; Deeg, H. J.; Díaz, R. F.; Dreizler, S.; Dreyer, C.; Eggenberger, P.; Ehrenreich, D.; Eigmüller, P.; Erikson, A.; Farmer, R.; Feltzing, S.; de Oliveira Fialho, F.; Figueira, P.; Forveille, T.; Fridlund, M.; García, R. A.; Giommi, P.; Giuffrida, G.; Godolt, M.; Gomes da Silva, 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.; Johansen, A.; 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.; Nelson, R. P.; 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.; Salmon, S.; Santerne, A.; Schneider, J.; Schou, J.; Schuh, S.; Schunker, H.; Silva-Valio, A.; Silvotti, R.; Skillen, I.; Snellen, I.; Sohl, F.; Sousa, S. G.; Sozzetti, A.; Stello, D.; Strassmeier, K. G.; Švanda, M.; Szabó, Gy. 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.

    2014-11-01

    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 like ours, including potentially habitable planets? The PLATO 2.0 instrument consists of 34 small aperture telescopes (32 with 25 s readout cadence and 2 with 2.5 s candence) providing a wide field-of-view (2232 deg 2) and a large photometric magnitude range (4-16 mag). It focusses on bright (4-11 mag) 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 these bright stars 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 planned baseline observing strategy includes two long pointings (2-3 years) to detect and bulk characterize planets reaching into the habitable zone (HZ) of solar-like stars and an additional step-and-stare phase to cover in total about 50 % of the sky. PLATO 2.0 will observe up to 1,000,000 stars and detect and characterize hundreds of small planets, and thousands of planets in the Neptune to gas giant regime out to the HZ. It will therefore provide the first large-scale catalogue of bulk characterized planets with accurate radii, masses, mean densities and ages. This catalogue will include terrestrial planets at intermediate orbital distances, where surface temperatures are moderate. Coverage of this parameter range with statistical numbers of bulk characterized planets is unique to PLATO 2.0. The PLATO 2.0 catalogue allows us to e.g.: - complete our knowledge of planet diversity for low-mass objects, - correlate the planet mean density-orbital distance distribution with predictions from planet formation theories,- constrain the influence of planet migration and scattering on the architecture of multiple systems, and - specify how planet and system parameters change with host star characteristics, such as type, metallicity and age. The catalogue will allow us to study planets and planetary systems at different evolutionary phases. It will further provide a census for small, low-mass planets. This will serve to identify objects which retained their primordial hydrogen atmosphere and in general the typical characteristics of planets in such low-mass, low-density range. Planets detected by PLATO 2.0 will orbit bright stars and many of them will be targets for future atmosphere spectroscopy exploring their atmosphere. Furthermore, the mission has the potential to detect exomoons, planetary rings, binary and Trojan planets. The planetary science possible with PLATO 2.0 is complemented by its impact on stellar and galactic science via asteroseismology as well as light curves of all kinds of variable stars, together with observations of stellar clusters of different ages. This will allow us to improve stellar models and study stellar activity. A large number of well-known ages from red giant stars will probe the structure and evolution of our Galaxy. Asteroseismic ages of bright stars for different phases of stellar evolution allow calibrating stellar age-rotation relationships. Together with the results of ESA's Gaia mission, the results of PLATO 2.0 will provide a huge legacy to planetary, stellar and galactic science.

  8. Art Education 2.0

    NSDL National Science Digital Library

    Roland, Craig

    Craig Roland created this site for fellow travelers and art educators in order to help colleagues find out how to use new technologies in their classrooms. First-time visitors will need to start out by signing up for a free account, and after that they are most welcome to participate in forums, groups, blogs, RSS feeds, and photo and video sharing. Some of the groups include "Art Partners", "Students of Art Education 2.0", and "First Year Art Teachers". The forums are quite useful, and recently they have included discussions on summer research opportunities, arts censuses, and the use of streaming video in the classroom. For art educators, this site is quite a find, and others who are interested in art and technology more generally will also find it useful.

  9. The solar wind charge-transfer X-ray emission in the 1/4 keV energy range: inferences on Local Bubble hot gas at low Z

    E-print Network

    D. Koutroumpa; R. Lallement; J. C. Raymond; V. Kharchenko

    2008-12-19

    We present calculations of the heliospheric SWCX emission spectra and their contributions in the ROSAT 1/4 keV band. We compare our results with the soft X-ray diffuse background (SXRB) emission detected in front of 378 identified shadowing regions during the ROSAT All-Sky Survey (Snowden et al. 2000). This foreground component is principally attributed to the hot gas of the so-called Local Bubble (LB), an irregularly shaped cavity of ~50-150 pc around the Sun, which is supposed to contain ~10^6 K plasma. Our results suggest that the SWCX emission from the heliosphere is bright enough to account for most of the foreground emission towards the majority of low galactic latitude directions, where the LB is the least extended. In a large part of directions with galactic latitude above 30deg the heliospheric SWCX intensity is significantly smaller than the measured one. However, the SWCX R2/R1 band ratio differs slightly from the data in the galactic center direction, and more significantly in the galactic anti-centre direction where the observed ratio is the smallest. Assuming that both SWCX and hot gas emission are present and their relative contributions vary with direction, we tested a series of thermal plasma spectra for temperatures ranging from 10^5 to 10^6.5 K and searched for a combination of SWCX spectra and thermal emission matching the observed intensities and band ratios, while simultaneously being compatible with O VI emission measurements. In the frame of collisional equilibrium models and for solar abundances, the range we derive for hot gas temperature and emission measure cannot reproduce the Wisconsin C/B band ratio. We emphasize the need for additional atomic data, describing consistently EUV and X-ray photon spectra of the charge-exchange emission of heavier solar wind ions.

  10. Validation Results for LEWICE 2.0

    NASA Technical Reports Server (NTRS)

    Wright, William B.; Rutkowski, Adam

    1999-01-01

    A research project is underway at NASA Lewis to produce a computer code which can accurately predict ice growth under any meteorological conditions for any aircraft surface. This report will present results from version 2.0 of this code, which is called LEWICE. This version differs from previous releases due to its robustness and its ability to reproduce results accurately for different spacing and time step criteria across computing platform. It also differs in the extensive amount of effort undertaken to compare the results in a quantified manner against the database of ice shapes which have been generated in the NASA Lewis Icing Research Tunnel (IRT). The results of the shape comparisons are analyzed to determine the range of meteorological conditions under which LEWICE 2.0 is within the experimental repeatability. This comparison shows that the average variation of LEWICE 2.0 from the experimental data is 7.2% while the overall variability of the experimental data is 2.5%.

  11. High-efficiency B?C/Mo?C alternate multilayer grating for monochromators in the photon energy range from 0.7 to 3.4 keV.

    PubMed

    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. PMID:24686695

  12. Experimental and MC determination of HPGe detector efficiency in the 40-2754 keV energy range for measuring point source geometry with the source-to-detector distance of 25 cm.

    PubMed

    Dryak, Pavel; Kovar, Petr

    2006-01-01

    A precise model of a 40% relative efficiency p-type HPGe detector was created for photon detection efficiency calculation using the MCNP code. All detector parameters were determined by different experiments. No experimental calibration points were used for the modification of detector parameters. The model was validated by comparing calculated and experimental full energy peak efficiencies in the 40-2754 keV energy range, for point-source geometry with the source-to-detector distance of 25 cm. PMID:16564693

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

    E-print Network

    Volker Beckmann; Neil Gehrels; Jack Tueller

    2007-04-20

    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 hot plasma are constant, while the amount of plasma varies, due to long-term flaring activity.

  14. Sputtering and Molecular Synthesis Induced by 100 keV Protons in Condensed CO2 and Relevance to the Outer Solar System

    NASA Astrophysics Data System (ADS)

    Raut, U.; Baragiola, R. A.

    2013-07-01

    We present results on sputtering and radiation chemistry of CO2 films induced by 100 keV H+ at 25 and 50 K. Using a quartz crystal microbalance, we measure a sputtering yield (SY) between ~10 and 20 CO2 equivalent per ion at 25 K. The yield at 50 K is similar to that at 25 K at low fluences, but increases to ~2400 by mid-1014 H+ cm-2 and declines at higher fluence. Irradiation to 1 × 1015 H+ cm-2 depletes ~85%-90% of the initial film mass at 50 K, compared to 3% at 25 K. In both cases, mass spectrometry shows that CO is the dominant constituent in the sputtered flux, followed by O2, O, and CO2. Using infrared spectroscopy, we monitor the depletion of CO2 and the accumulation of CO and O2 and minor species as O3 and CO3. We determine G(-CO2) = 2.6 ± 0.3, the number of CO2 destroyed per 100 eV at 25 K. A significant fraction of the radiolyzed CO and O2 are retained in the film at 25 K; only those near the surface are removed during irradiation, contributing to a smaller SY. At 50 K, CO and O2 are unstable along the "hot" ion track and are expelled possibly from the entire depth of the film. Our results, and the lack of detection of CO in the exospheres around Rhea and Dione, show that the CO2 does not originate from sputtering, since otherwise the exosphere would be dominated by CO, the main molecule in the sputtered flux. We suggest that the exospheric CO2 is thermally released from an endogenic source.

  15. Thermal properties of aminopolycarboxylic acid solutions in the temperature range 20 80°C

    NASA Astrophysics Data System (ADS)

    Osman, M. B. S.; Dakroury, A. Z.

    1994-07-01

    The thermal properties (thermal conductivity, thermal diffusivity, and volumetric heat capacity) of aminopolycarboxylic acids, nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), diet hylenetriaminepentaacetic acid (DTPA), triethylenetetraminehexaacetic acid (TTHA), 1,2-diaminocyclohexanetetraacetic acid (DCTA), and ethyleneglycol-bis-(2-aminoethylether) tetraacetic acid (EGTA), in dilute solutions of sodium hydroxide were measured in the temperature range 20 80°C. The measurements were performed with a hot-wire (strip) technique. The results show that the values of the thermal properties depend on the number of nitrogen atoms and the number of carboxyalkyl groups, which are bounded to the nitrogen atom, of the aminopolycarboxylic acid and also on the concentration of the investigated compounds in the medium and the temperatures. The mechanism of heat transfer is discussed and the role of convection is taken into consideration.

  16. Using Web 2.0 to Collaborate

    ERIC Educational Resources Information Center

    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…

  17. State-selective nonresonant transfer excitation in 50--400-keV sup 3 He sup + +H sub 2 and He collisions

    SciTech Connect

    Jain, A. (Department of Physics, Florida A M University, Box 981, Tallahassee, Florida 32307 (US)); Shingal, R. (Department of Physics, Kansas State University, Manhattan, Kansas 66506 (USA)); Zouros, T.J.M. (Department of Physics, University of Crete, Iraklion and Foundation for Research an Technology-Hellas (FORTH), Iraklion (Greece))

    1991-02-01

    Cross sections for nonresonant transfer excitation (NTE) are calculated for collisions of {sup 3}He{sup +} with H{sub 2} (2H) and He targets in the 50--500-keV impact-energy range. Single-electron capture probabilities to the 2{ital s} and 2{ital p} orbitals of He and single-electron excitation probabilities for He{sup +} (1{ital s}{r arrow}2{ital s} or 2{ital p}) transitions are independently computed, as a function of impact parameter, using the semiclassical multichannel-impact-parameter model with an expansion in atomic orbitals placed either on one or both centers. NTE cross sections for the (2{ital s}{sup 2}){sup 1}{ital S}, (2{ital p}{sup 2}){sup 1}{ital D}, and (2{ital s}2{ital p}){sup 1}{ital P} states, computed in the independent-electron model, are compared with the recent high-resolution electron data for transfer excitation into these states. For He{sup +}+H{sub 2} collisions, NTE is found to contribute primarily at the low collision energies, dropping off at the higher energies. On the contrary, for the symmetric He{sup +}+He collisions, NTE cross sections do not drop off with impact energy as expected. In the case of the (2{ital p}{sup 2}){sup 1}{ital D} state, an increase in the cross section, similar to the experimental data, is seen. However, in both cases, the calculated cross section seems to be larger than the experimental data.

  18. DECAYS OF THE Tz = -2 NUCLEI 20Mg, 24Si AND 36Ca

    SciTech Connect

    Aysto, J.; Cable, M.D.; Parry, R.F.; Wouters, J.M.; Moltz, D.M.; Cerny, J.

    1980-06-01

    Beta-delayed protons have been observed from the decays of the mass separated T{sub z} = -2 nuclides {sup 20}Mg, {sup 24}Si, and {sup 36}Ca. From these proton spectra the mass excesses of the lowest T = 2 states in the T{sub z} = -1 nuclei {sup 20}Na, {sup 24}Al, and {sup 36}K are determined to be 13420 {+-} 50 keV ({sup 20}Na), 5903 {+-} 9 keV ({sup 24}Al), and - 13168 {+-} 22 keV ({sup 36}K). The complete A = 20, 24, and 36 isospin quintets have all their members bound against isospin allowed particle-decay modes, providing a stringent test of the isobaric multiplet mass equation. Good agreement is observed for all these quintets using only the quadratic form of this equation. Radioactivity {sup 20}Mg, {sup 24}Si, {sup 36}Ca (mass separated); measured {beta}-delayed protons; deduced T{sub 1/2} and proton branching; derived mass excesses of the lowest 0{sup +}, T = 2 states in {sup 20}Na, {sup 24}Al, and {sup 36}K; deduced coefficients of the isobaric multiplet mass equation.

  19. Experimental determination of the real elements of the density matrix of H({ital n}=3) atoms produced in 20--100-keV collisions of H{sup +} on Kr

    SciTech Connect

    Seifert, N.; Gibson, N.D.; Risley, J.S. [Atomic Collision Laboratory, Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202 (United States)] [Atomic Collision Laboratory, Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202 (United States)

    1995-11-01

    In continuation of our previous work, charge transfer processes occurring in protons on rare-gas-atom collisions have been investigated. Diagonal and real off-diagonal coherence elements of the density matrix for H({ital n}=3) atoms produced in 20--100-keV electron-capture collisions with Kr atoms are experimentally determined by analyzing the Balmer-{alpha} light from the decay of H atoms from the ({ital n}=3) state to the ({ital n}=2) state. The intensity and polarization of the emitted light are measured as functions of an axially symmetric electric field in the collision region. These data are fitted to a numerical model of the H atom in an electric field in order to extract density-matrix elements. The results are compared to previous studies of H{sup +} on He and Ar. The collisionally produced dipole moment of the H({ital n}=3) atom decreases for increasing atomic number of the rare-gas target atoms, which indicates that the final phase of the collision process is not essential for the formation of the dipole moment. This physical picture is further supported by our alignment data. Absolute cross sections for charge transfer to the 3{ital s}, 3{ital p}, and 3{ital d} levels are presented as well.

  20. Experimental determination of real elements of the density matrix and the dipole moment of H([ital n]=3) atoms produced from 20--100-keV H[sup +] on Ar

    SciTech Connect

    Renwick, S.P.; Martell, E.C.; Weaver, W.D.; Risley, J.S. (Atomic Collisions Laboratory, Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202 (United States))

    1993-10-01

    Diagonal and real off-diagonal coherence elements of the density matrix for H([ital n]=3) atoms produced in 20--100-keV electron-capture collisions of protons with Ar atoms are experimentally determined. Balmer-[alpha] light from the decay of H atoms from the ([ital n]=3) state to the ([ital n]=2) state is observed. The intensity and polarization of the light as a function of an axially symmetric electric field in the collision region are fitted to a numerical model of the H atom in an electric field in order to extract density-matrix elements. A new polarimeter, using a photoelastic modulator in conjunction with photon-counting techniques, is used in the experiment, and its efficacy is analyzed and compared to that of a rotating quarter-wave plate polarimeter previously used in similar experiments. The diagonal elements of the density matrix yield relative capture cross sections for the H(3[ital l]) angular-momentum substates, while the coherence terms are used to determine the dipole moment of the atoms produced. Results are compared to those for protons colliding with a He target and the differences are discussed.

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

    PubMed

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

    2015-04-01

    The MCNP5 radiation transport code was used to quantify changes in the absorbed dose conversion factor for LiF, Al2O3, and silicon-based electronic dosimeters calibrated in-air using standard techniques and summarily used to measure absorbed dose to water when placed in a water phantom. A mono-energetic photon source was modeled at energies between 30 keV and 300 keV for a point-source placed at the center of a water phantom, a point-source placed at the surface of the phantom, and for a 10-cm radial field geometry. Dosimetric calculations were obtained for water, LiF, Al2O3, and silicon at depths of 0.2 cm and 10 cm from the source. These results were achieved using the MCNP5 *FMESH photon energy-fluence tally, which was coupled with the appropriate DE/DF card for each dosimetric material studied to convert energy-fluence into the absorbed dose. The dosimeter's absorbed dose conversion factor was calculated as a ratio of the absorbed dose to water to that of the dosimeter measured at a specified phantom depth. The dosimeter's calibration value also was obtained. Based on these results, the absorbed dose conversion factor for a LiF dosimeter was found to deviate from its calibration value by up to 9%, an Al2O3 dosimeter by 43%, and a silicon dosimeter by 61%. These data therefore can be used to obtain LiF, Al2O3, and silicon dosimeter correction factors for mono-energetic and poly-energetic sources at measurement depths up to 10 cm under the irradiation geometries investigated herein. PMID:25706137

  2. The PLATO 2.0 Mission

    E-print Network

    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...

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

    SciTech Connect

    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.

  4. 50 CFR 30.2 - Disposition of surplus range animals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Disposition of surplus range animals. 30.2 Section 30.2 Wildlife and Fisheries...NATIONAL WILDLIFE REFUGE SYSTEM RANGE AND FERAL ANIMAL MANAGEMENT Range Animals § 30.2 Disposition of surplus range...

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

    SciTech Connect

    Castleton, Karl J.; Meyer, Philip D.

    2009-06-17

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

  6. Development of the EXITE detector - A new imaging detector for 20 - 300 keV astronomy. [Energetic X-ray Imaging Telescope Experiment

    NASA Technical Reports Server (NTRS)

    Garcia, M. R.; Grindlay, J. E.; Burg, R.; Murray, S. S.; Flanagan, J.

    1986-01-01

    The development and testing of a detector to be used in the Energetic X-ray Imaging Telescope Experiment (EXITE) are reported. It consists of a 34 cm diameter NaI(Tl) crystal coupled directly to a single large image intensifier tube with associated silicon PIN diode readout. The measured spatial and energy resolutions at 122 keV are 6mm (FWHM) and 9 percent (FWHM), respectively. This energy resolution is about 50 percent better than that of any previously flown hard X-ray experiment. These resolutions decrease with the square root of the energy of the incident X-ray, indicating that they are determined by the number of photons emitted in the NaI(Tl) scintillator light flash.

  7. Entrepreneurship education and Web 2.0

    Microsoft Academic Search

    Brian Jones; Norma Iredale

    2009-01-01

    Purpose – The social nature of the Web 2.0 environment creates marketing opportunities via shared learning through online exchange of views. Web 2.0 creates opportunities and poses challenges for, amongst other things, the management of education and business reputation. This paper aims to look at Web 2.0 and explore the uses to which it might be put in furthering entrepreneurship

  8. Electron emission yield from thin Al and insulating layers induced by 3 MeV He 2+ and 3 keV electron impact

    Microsoft Academic Search

    M. Steinbatz; A. Schinner; E. Steinbauer; O. Benka

    2002-01-01

    The kinetic electron yield was measured for the impact of 3 MeV He2+ ions and 3 keV electrons on thin layers of Al on Cu, of Al2O3 on Al, and of CeO2 and CaF2 on Si backings. The dependence of the yield on the layer thickness was determined. For Al on Cu a decreasing yield was observed for increasing Al

  9. A simple viscoelastic model for soft tissues the frequency range 6-20 MHz

    Microsoft Academic Search

    Xinmai Yang; Charles C. Church

    2006-01-01

    In this paper, we present measurements of the shear properties of porcine skeletal muscle, liver, and kidney and a novel model describing them. Following a previously used method, shear mechanical impedances are measured, and complex shear moduli are obtained in the frequency range 6-20 MHz. As indicated in previous results, negative storage moduli are obtained in some measurements, which yield

  10. 50 keV electron-beam projection maskless lithography (PML2): results obtained with 2,500 programmable 12.5-nm sized beams

    NASA Astrophysics Data System (ADS)

    Klein, Christof; Klikovits, Jan; Szikszai, Laszlo; Platzgummer, Elmar; Loeschner, Hans

    2010-03-01

    Projection Mask-Less Lithography (PML2) is a potentially cost-effective electron multi-beam solution for the 16 nm hp ITRS technology node and beyond. First results obtained with a PML2 Testbench are presented where a programmable Aperture Plate System (APS) was used to generate ca. 2500 micrometer-sized beams which are projected onto wafer level with 200x demagnification. The APS contains CMOS electronics which allows for addressable deflection of selected beams; only non-deflected beams make it to the wafer surface to achieve 12.5 nm spot size. Beam energy (50keV) and current density (~2 A/cm2) are the same as in future PML2 production tools. Thus, the results obtained with the PML2 Testbench unambiguously prove the patterning capabilities of the PML2 technology.

  11. Short-range ordering and the abnormal mechanical properties of a Ni-20% Cr alloy

    NASA Astrophysics Data System (ADS)

    Dudova, N. R.; Kaibyshev, R. O.; Valitov, V. A.

    2009-12-01

    Effect of temperature on mechanical properties of a Ni-20% Cr alloy with an initial grain size of 100 µm in the temperature interval 150-1000°C (0.25-0.8 T m) has been studied. It is shown that in the temperature range 400-600°C the alloy demonstrates a positive temperature dependence of both the flow stress and the coefficient of strain hardening and exhibits Portevin-le Chatelier effect (PLC). It has been established on the basis of a comparison of data of calorimetric studies and temperature dependence of mechanical properties that the unusual mechanical behavior of Ni-20% Cr alloy is a result of the occurrence of short-range order. The nature of the effect of the short-range order on the mechanical properties is discussed.

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

    NASA Astrophysics Data System (ADS)

    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 ( ?- and ?-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 ?- and ?-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 K and is independent of the crystalline structure. In addition, this survival would increase if the molecular species were protected by several layers of other molecular species as trapped in comet mantles or embedded within regolith in asteroids/lunar surfaces. The understanding of the excitation and dissociation processes of organic compounds in space simulation is highly required to put constrains in the puzzle over the origin of life in the primitive Earth.

  13. DCC Briefing Paper: Web 2.0 

    E-print Network

    Abbott, Daisy

    2010-01-01

    The term 'Web 2.0' refers to a way of thinking about networked communications; a collaborative and social way of working underpinned by the key concept of the Web (rather than the desktop) as a platform. Web 2.0 is characterised by data sharing...

  14. 20 CFR 219.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    20 Employees' Benefits 1 2011-04-01...2 Section 219.2 Employees' Benefits RAILROAD RETIREMENT... Benefit means any employee annuity, spouse annuity...evidence that proves to the satisfaction of the Board that...

  15. 20 CFR 219.2 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    20 Employees' Benefits 1 2013-04-01...2 Section 219.2 Employees' Benefits RAILROAD RETIREMENT... Benefit means any employee annuity, spouse annuity...evidence that proves to the satisfaction of the Board that...

  16. 20 CFR 219.2 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    20 Employees' Benefits 1 2014-04-01...2 Section 219.2 Employees' Benefits RAILROAD RETIREMENT... Benefit means any employee annuity, spouse annuity...evidence that proves to the satisfaction of the Board that...

  17. 20 CFR 219.2 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    20 Employees' Benefits 1 2012-04-01...2 Section 219.2 Employees' Benefits RAILROAD RETIREMENT... Benefit means any employee annuity, spouse annuity...evidence that proves to the satisfaction of the Board that...

  18. 20 CFR 219.2 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    20 Employees' Benefits 1 2010-04-01...2 Section 219.2 Employees' Benefits RAILROAD RETIREMENT... Benefit means any employee annuity, spouse annuity...evidence that proves to the satisfaction of the Board that...

  19. 2-10 keV luminosity of high-mass binaries as a gauge of ongoing star-formation rate

    Microsoft Academic Search

    M. Persic; Y. Rephaeli; V. Braito; M. Cappi; R. Della Ceca; A. Franceschini; D. E. Gruber

    2004-01-01

    Based on recent work on spectral decomposition of the emission of star-forming galaxies, we assess whether the integrated 2-10 keV emission from high-mass X-ray binaries (HMXBs), L2-10HMXB, can be used as a reliable estimator of ongoing star formation rate (SFR). Using a sample of 46 local (z ⪅ 0.1) star-forming galaxies, and spectral modeling of ASCA, BeppoSAX, and XMM-Newton data,

  20. Impact-collision ion-scattering spectroscopy of Cu(110) and Cu(110)-(2×1)-O using 5keV 6Li+

    Microsoft Academic Search

    Jory A. Yarmoff; Donna M. Cyr; Judy H. Huang; Sehun Kim; R. Stanley Williams

    1986-01-01

    Impact-collision ion-scattering spectroscopy was performed using 5-keV 6Li+ ions to study the Cu(110) and Cu(110)-(2×1)-O surfaces. Polar-angle scans were collected for scattering along the [11¯0], [11¯2], and [001] azimuths. These scans were quantitatively analyzed by comparing them to the results of an algorithm that combined a one-atom Monte Carlo computer simulation with various structural models to calculate trial polar scans.

  1. 5/3/13 2:21 PMNew Director Promises to Cultivate Rose Art Museum's Growth | Brandeis Magazine Page 1 of 2file:///Users/Rose-Student/Desktop/New%20Director%20Promises%20to...20Art%20Museum's%20Growth%20%7C%20Brandeis%20Magazine.webarchive

    E-print Network

    Snider, Barry B.

    5/3/13 2:21 PMNew Director Promises to Cultivate Rose Art Museum's Growth | Brandeis Magazine Page%20%7C%20Brandeis%20Magazine.webarchive New Director Promises to Cultivate Rose Art Museum's Growth | Brandeis Magazine Page 2 of 2file:///Users/Rose-Student/Desktop/New%20Director%20Promises%20to...20Art%20

  2. Measuring the linear polarization of $?$s in 20-170 GeV range

    E-print Network

    G. Unel

    2002-11-29

    The Na59 collaboration aims to measure the linear polarization of its photon beam in the 20-170 GeV range, using an aligned thin crystal. The tracks of $e^-/e^+$ pairs created in two different crystal targets, germanium and diamond, are reconstructed to obtain the photon spectrum. Using the polarization dependence of the pair production cross section in an aligned crystal, photon polarization is obtained to be 55% at the vicinity of 70 GeV.

  3. Elastic moduli of titanium-hydrogen alloys in the temperature range 20 °C to 1100 °C

    Microsoft Academic Search

    O. N. Senkov; M. Dubois; J. J. Jonas

    1996-01-01

    The elastic properties of a series of polycrystalline titanium-hydrogen alloys (containing up to 25 at. pct H) were measured\\u000a over the temperature range 20 C to 1100 C. The latter limits permitted investigation of adjacent parts of the ?+?, ?, and\\u000a ? phase fields. A laser ultrasonic technique was employed to measure the temperature and hydrogen-concentration dependencies\\u000a of the elastic

  4. Impact-collision ion-scattering spectroscopy of Cu(110) and Cu(110)-(2 x 1)-O using 5keV ⁶Li\\/sup +

    Microsoft Academic Search

    J. A. Yarmoff; D. M. Cyr; J. H. Huang; S. Kim; R. S. Williams

    1986-01-01

    Impact-collision ion-scattering spectroscopy was performed using 5-keV ⁶Li\\/sup +\\/ ions to study the Cu(110) and Cu(110)-(2 x 1)-O surfaces. Polar-angle scans were collected for scattering along the (110), (112), and (001) azimuths. These scans were quantitatively analyzed by comparing them to the results of an algorithm that combined a one-atom Monte Carlo computer simulation with various structural models to calculate

  5. 2. (Art Nouveau) 19 20 1400 ~ 1500

    E-print Network

    Lin, Jason Yi-Bing

    7 / 1 ( 40 2 ) 1. A. B. C. D. 2. (Art Nouveau) 19 20 A. B. C. D. 3. . . . . 101 101 2 5 1400 ~ 1500 #12; 7 / 2 A. B. C. D. 4. A. B. C. D. 5. (Arts & Crafts Movement) A. (Marcel Duchamp) B. C. D. #12; 7 / 4 16. (Land Art Earth Art) A. (Chuck Close) B. (Michael Heizer

  6. Short-range ordering and mechanical properties of a Ni-20%Cr alloy

    NASA Astrophysics Data System (ADS)

    Dudova, N. R.; Kaibyshev, R. O.

    2010-07-01

    The mechanical behavior of a coarse-grained (100 ?m) nickel-base alloy nichrome (Ni-20%Cr) was studied in compression at temperatures ranging from 150 to 1000°C. It was shown that in the temperature interval of 300-600°C this alloy demonstrates the following features of mechanical behavior: i) positive temperature dependence of yield stress; ii) jerky flow associated with the Portevin-Le Chatelier (PLC) effect; 3) very high value (115 MPa) of "threshold" stress at 650°C. These features of mechanical behavior can be related to short-range ordering (SRO). It was shown by differential scanning calorimetry that SRO takes place in this temperature range, causing PLC effect and positive temperature dependence of yield stress. In addition, SRO has persistency effect on yield stress and creep resistance.

  7. Version 2.0 JWST Primer

    E-print Network

    Sirianni, Marco

    .0 Introduction The aim of this document is to provide an overview of the James Webb Space Telescope (JWST), its by JWST. Finally, Section 7 lists a number of information resources. 2.0 JWST Science Goals The James Webb

  8. 36 CFR 20.2 - Permits; conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    36 Parks, Forests, and Public Property...Section 20.2 Parks, Forests, and Public Property...use of Government-owned structures and facilities in...fishermen, where such structures and facilities were...

  9. 36 CFR 20.2 - Permits; conditions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    36 Parks, Forests, and Public Property...Section 20.2 Parks, Forests, and Public Property...use of Government-owned structures and facilities in...fishermen, where such structures and facilities were...

  10. Web 2.0 and You!

    NSDL National Science Digital Library

    Brenda A. Dyck

    Web 2.0 tools, when used in concert with solid constructivist teaching principles, have the potential to engage digital learners in their own education. These tools are more than resources; they are vital elements in meaningful instruction.

  11. The PLATO 2.0 Mission

    NASA Astrophysics Data System (ADS)

    Pagano, I.; Rauer, H.; Aerts, C.; Appourchaux, T.; Benz, W.; Brandeker, A.; Christensen-Dalsgaard, J.; Deleuil, M.; Gizon, L.; Goupil, M.-J.; Guedel, M.; Heras, A.; Janot-Pacheco, E.; Mas-Hesse, M.; Piotto, G.; Pollaco, D.; Ragazzoni, R.; Santos, N. C.; Smith, A.; Suarez, J. C.; Szabo, R.; Udry, S.

    2014-04-01

    PLATO 2.0 is the M class mission selected by ESA for its M3 launch slot in the framework of the Cosmic Vision 2015-2025 program. The main goals of PLATO 2.0 are the detection of terrestrial exoplanets in the habitable zone of solar-type stars and the characterization of their bulk properties needed to determine their habitability. Moreover, PLATO 2.0 will be key in understanding the formation, architecture, and evolution of planetary systems thanks to a thorough inventory of the physical properties of thousands of rocky, icy, and gaseous giant planets. We will illustrate the PLATO 2.0 science goals, how the instrument is conceived to fulfil the science requirements, and how the project is organized to implement the instrument, plan the observations, and exploit the resulting data.

  12. Web Lectures and Web 2.0

    Microsoft Academic Search

    Markus Ketterl; Robert Mertens; Oliver Vornberger

    2008-01-01

    At many universities, web lectures have become an integral part of the e-learning portfolio over the last few years. While many aspects of the technology involved, like automatic recording techniques or innovative interfaces for replay, have evolved at a rapid pace, web lecturing has been independent of other important developments such as Web 2.0. Web 2.0 is an emerging trend

  13. The PLATO 2.0 mission

    NASA Astrophysics Data System (ADS)

    Rauer, H.

    2013-09-01

    PLATO 2.0 is the next generation space-based survey for transiting extrasolar planets and is proposed to ESA as a candidate for the M3 slot within the ESA Cosmic Vision 2015-2025 program. Its main objectives are the detection of Earth Analogue systems around bright stars, and to reveal the interior structure of planets and their host stars. We will present here the expected scientific impact of the PLATO 2.0 mission.

  14. X-ray observations between 10 and 150 keV from the Alcator-C tokamak

    NASA Astrophysics Data System (ADS)

    Rice, J. E.; Chamberlain, K. L.

    1988-08-01

    A mercuric iodide (HgI2) detector has been used to obtain x-ray spectra in the energy range from 5 to 200 keV from the Alcator-C tokamak. During high-density Ohmic operation of Alcator-C, this detection system provides a reliable electron-temperature diagnostic. Nonthermal x-ray spectra above 20 keV are observed under certain conditions when a substantial amount of lower-hybrid rf (LHRF) power is injected. The magnitude of this nonthermal behavior strongly increases as the electron density is lowered and is more pronounced in deuterium plasmas than in hydrogen. Model electron distribution functions, which can give rise to the observed x-ray spectra, are discussed.

  15. Light Sources in the 0.15-20-micro Spectral Range.

    PubMed

    Cann, M W

    1969-08-01

    The different kinds of light sources available for the 0.15-20-micro spectral range are surveyed. Information was obtained from the published literature, unpublished reports, light source manufacturers, and also from individual persons. The aim has been to present sufficient information, where available, to show the relative advantages of different sources-intensity, stability, and output uniformity were of prime interest. Continuum and line sources are included but lasers and pulsed sources are omitted. The sources are described under the main headings: Arc Discharge Sources, Glow Discharge Sources, and Incandescent Sources, with another section, Miscellaneous Sources, to cover some which could not be included under the first three headings. PMID:20072491

  16. Short-range ordering and the abnormal mechanical properties of a Ni20% Cr alloy

    Microsoft Academic Search

    N. R. Dudova; R. O. Kaibyshev; V. A. Valitov

    2009-01-01

    Effect of temperature on mechanical properties of a Ni-20% Cr alloy with an initial grain size of 100 µm in the temperature\\u000a interval 150–1000°C (0.25–0.8 T\\u000a m) has been studied. It is shown that in the temperature range 400–600°C the alloy demonstrates a positive temperature dependence\\u000a of both the flow stress and the coefficient of strain hardening and exhibits Portevin-le

  17. Measurement of the ratio of double-to-single photoionization of helium at 2.8 keV using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Levin, J. C.; Lindle, D. W.; Keller, N.; Miller, R. D.; Azuma, Y.; Mansour, N. Berrah; Berry, H. G.; Sellin, I. A.

    1991-08-01

    We report the first measurement of the ratio of double-to-single photoionization of helium well above the double-ionization threshold. Using a time-of-flight technique, we find He++/He+=1.6+/-0.3% at h?=2.8 keV. This value lies between calculations by Amusia (2.3%) and by Samson, who predicts 1.2% by analogy with electron-impact ionization cross sections of singly charged ions. Good agreement is obtained with older shake calculations of Byron and Joachain, and of Åberg, who predict 1.7%.

  18. Using Web 2.0 for Learning in the Community

    ERIC Educational Resources Information Center

    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,…

  19. 20 4000 2 GPS SUTNet GPS

    E-print Network

    .Return Q Q 2 T NO(T) O(N) O(kMlgM) k Q M T 4.4 (DHA) [2] SUTNet 4.5 (DOAPM 1900PM 100 TPA SPAARADHA DOA DOA TPASPAARA DHA 1 ARA DHA SPA TPA 1 TPA TPA TPA ARA DHA #12; 5 DHA ARA 41% TPA 10%13% 20% 6. ARA [1

  20. 20 CFR 655.20 - Assurances and obligations of H-2B employers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Assurances and obligations of H-2B employers. 655.20 Section 655.20 Employees' Benefits EMPLOYMENT AND TRAINING...States (H-2B Workers) Assurances and Obligations § 655.20 Assurances and obligations of H-2B...

  1. 20 CFR 655.20 - Assurances and obligations of H-2B employers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Assurances and obligations of H-2B employers. 655.20 Section 655.20 Employees' Benefits EMPLOYMENT AND TRAINING...States (H-2B Workers) Assurances and Obligations § 655.20 Assurances and obligations of H-2B...

  2. Sputtering of cryogenic films of hydrogen by keV ions: Thickness dependence and surface morphology.

    E-print Network

    . Jørgen Schou1 and Noel Hilleret2 The solid hydrogen isotopes are the most volatile solids which exist in equilibrium with vacuum. For bombardment with 10 keV hydrogen ions the sputtering yield of these solids ranges at a temperature of 2-3 K, and the thickness ranged from a fraction of a monolayer up to several thousands

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

    NASA Astrophysics Data System (ADS)

    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.

  4. Social Participation in Health 2.0

    PubMed Central

    Hesse, Bradford W.; Hansen, Derek; Finholt, Thomas; Munson, Sean; Kellogg, Wendy; Thomas, John C.

    2010-01-01

    Computer scientists are working with biomedical researchers, policy specialists, and medical practitioners to usher in a new era in healthcare. A recently convened panel of experts considered various research opportunities for technology-mediated social participation in Health 2.0. PMID:21379365

  5. Professional Development and Web 2.0

    ERIC Educational Resources Information Center

    Jakes, David

    2007-01-01

    Professional development in most schools has a predictable look and feel: summer workshops, brown-bag luncheon trainings, and the infamous in-service day. These events can be successful, and there is no doubt they have helped numerous educators become better at what they do. Web 2.0, however, opens up a new world of professional learning. This…

  6. COMPONENTVersion 2.0 Tree Comparsion Software

    E-print Network

    Page, Roderic

    COMPONENTVersion 2.0 Tree Comparsion Software for Microsoft® WindowsTM User's Guide Roderic D. M NO WARRANTY, EITHER EXPRESSED OR IMPLIED, WITH RESPECT TO THIS SOFTWARE, ITS QUALITY, PERFORMANCE, MERCHANTABILITY, OR FITNESS FOR A PARTICULAR PURPOSE. AS A RESULT, THIS SOFTWARE IS SOLD "AS IS", AND YOU

  7. Do Web 2.0 Right

    ERIC Educational Resources Information Center

    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…

  8. 2.0New York solar roadmap

    E-print Network

    Perez, Richard R.

    - neering (CNSE) at the University at Albany, together with 30 industry partners, prepared New York's Solar2.0New York solar roadmap A plan for energy reliability, security, environmental responsibility, University at Albany 101-SolarRoadMap_r6Final.indd 1 7/17/12 12:00:08 AM #12;With the aim of preparing

  9. Educational Uses of Web 2.0

    NSDL National Science Digital Library

    Qaissaunee, Michael

    Educational Uses of Web 2.0 is a presentation that was delivered at the SAME-TEC advanced technological education conference on July 30, 2008 by Mike Qaissaunee and Gordon Synder of NCTT. This presentation covers: blogs, cellphones, webware, mindmapping, video-online meetings, information gathering, ultra-aggregators, bookmarks.

  10. Looking for Collection 2.0

    ERIC Educational Resources Information Center

    Buczynski, James A.

    2008-01-01

    Libraries are integrating Web 2.0 services into work practices, positioning themselves in online social environments, and deploying enhanced search and discovery tools. Collections conversely are not progressing to the same degree. Like many public services today, library budgets are stained. User-pay options are appearing in library systems,…

  11. Science 2.0: Summer Surfing

    NSDL National Science Digital Library

    Eric Brunsell

    2010-07-01

    What better way to spend a sunny summer day than surfing--the web, that is! With so many web 2.0 applications out there, it's hard to know what's really useful. In this month's column, the authors share some of their favorite free sites for educat

  12. Platform Independent Perseus 2.0

    NSDL National Science Digital Library

    The Perseus Project at Tufts University (discussed in the October 17, 1997 Scout Report) is an ongoing initiative to create a comprehensive, interactive, multimedia digital library for the study of Archaic and Classical Greece. In 1998, the Perseus Project released a free beta version of Platform Independent Perseus 2.0. PIP2 is a graphical user interface for the Perseus 2.0 database, the latest version of the digital library. Once users install the interface locally, they may seamlessly access and navigate the numerous texts, maps, and images available on the Perseus server via an Internet connection. The benefit of PIP2 is that users are provided with a specialized interface for the online database and are able to avoid the annoying encumbrances encountered when using an unwieldy Web browser. Installation requirements and downloading instructions are posted at the site for both Mac and Windows operating systems.

  13. Cone Deck 2 Lot 20 Lot 21

    E-print Network

    Howitt, Ivan

    Cam eron Blvd. Cameron Blvd. Lot 25 MaryAlex Rd. East Deck 2 East Deck 3 John Kirk Dr Mary AlexanderM V M M V M M M M M M M V M V V M M Cone Deck 2 Lot 8A Lot 20 Lot 21 Lot 13 Lot16 Cone Deck 1 Lot 15 Lot 11A Parking Services Office University Police Headquarters Lot 11 Lot16 Lot 12 East Deck 1 H I

  14. Cone Deck 2 Lot 20 Lot 21

    E-print Network

    Howitt, Ivan

    . CameronBlvd. Alumni Way Cam eron Blvd. Cameron Blvd. Lot 25 MaryAlex Rd. East Deck 2 East Deck 3 John KirkCone Deck 2 Lot 8A Lot 20 Lot 21 Lot 13 Lot16 Cone Deck 1 Lot 15 Lot 11A Lot 11 Lot16 Lot 12 East. Field 14 Rec. Field 14a Hammer Throw Venture Course HTC Venture Course TC Lot 8 Lot MSU Resident & F

  15. Cone Deck 2 Lot 20 Lot 21

    E-print Network

    Howitt, Ivan

    Rd. CameronBlvd. Alumni Way Cam eron Blvd. Cameron Blvd. Lot 25 MaryAlex Rd. East Deck 2 East Deck 3Cone Deck 2 Lot 8A Lot 20 Lot 21 Lot 13 Lot16 Cone Deck 1 Lot 15 Lot 11A Lot 11 Lot16 Lot 12 East. Field 14 Rec. Field 14a Hammer Throw Venture Course HTC Venture Course TC Lot 8 Lot MSU Resident & F

  16. Web 2.0 and Geospatial Convergence

    E-print Network

    Zeiss, Geoff

    2007-11-14

    © 2005 Autodesk 1 Web 2.0 and Geospatial Convergence Geoff Zeiss, Director of Technology 6th Annual GIS Day @ KU Symposium © 2005 Autodesk 2 Worldwide Challenges © 2005 Autodesk 3 Global Climate Change The Norwegian Nobel Committee has decided... is Developing New Technologies © 2005 Autodesk 14 Location-enabling IT GIS Ge ne ral IT Ge ne ral IT Ge osp ati al en ab led 2005 / 2006 Examples: Web search, RDBMS, CAD, architectural design, engineering, … © 2005 Autodesk 15 Open Standards October 2007...

  17. Social Media: What's the Point of 2.0?Point of 2.0?

    E-print Network

    Social Media: What's the Point of 2.0?Point of 2.0? ORS Brown Bag Sessiong September 22, 2011 Krista Jensen Knowledge Mobilization Officer #12;Social Media Social Media is defined as "a group of InternetSocial Media is defined as a group of Internet based applications that build on the ideological

  18. CDM 2.0 (CLIMATOLOGICAL DISPERSION MODEL - VERSION 2.0) USER'S GUIDE

    EPA Science Inventory

    CDM-2.0 (Climatological Dispersion Model - Version 2.0) determines longterm (seasonal or annual) quasi-stable pollutant concentrations in rural or urban settings using average emission rates from point and area sources and a joint frequency distribution of wind direction, wind sp...

  19. Cross Sections and Swarm Coefficients for H + , H2 + , H3 + , H, H2, and H - in H2 for Energies from 0.1 eV to 10 keV

    Microsoft Academic Search

    A. V. Phelps

    1990-01-01

    Graphical and tabulated data and the associated bibliography are presented for cross sections for elastic, excitation and ionization collisions of H+, H2+, H3+, H, H2, and H? with H2 at laboratory energies from 0.1 to 10 keV. Where appropriate, drift velocities and reaction or excitation coefficients are calculated from the cross sections and recommended for use in analyses of swarm

  20. Kinetics of short-range and long-range B 2 ordering in FeCo

    SciTech Connect

    Fultz, B. (California Institute of Technology, 138-78, Pasadena, California (USA))

    1991-11-01

    Short-range and long-range-order parameters were measured by Moessbauer spectrometry and x-ray diffractometry during the disorder {r arrow}{ital B}2 order transformation in equiatomic FeCo. The change from a homogeneous mode of ordering at high temperatures to a heterogeneous mode of ordering at low temperatures was confirmed. By comparing parametric plots of the {sup 57}Fe hyperfine magnetic field versus long-range-order parameter for ordering in these two modes, an early independent relaxation of the short-range order was found in the kinetic path for homogeneous ordering. This relaxation was in reasonable agreement with estimates based on statistical kinetic theory.

  1. MicroSurfer 2.0

    NSDL National Science Digital Library

    MicroSurfer 2.0 is Web productivity software that enables faster Internet surfing. This newly release product eliminates backtracking in your browser; allows you to view Web pages without waiting; and allows you to collect, organize, and share links up to 400% faster. The software requiries Windows 95/98/2000/NT/Me/XP, direct or dial-up Internet access, and Microsoft Internet Explorer 4 or higher. MicroSurfer 2.0 edition is free for non-profit organizations and for individual personal use. For businesses, governmental entities, educational institutions, and those interested in a more advanced version of the software, the Plus edition may be purchased from the MicroSurfer online store.

  2. 33 CFR 2.20 - Territorial sea baseline.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Territorial sea baseline. 2.20 Section 2.20 Navigation...JURISDICTION Jurisdictional Terms § 2.20 Territorial sea baseline. Territorial sea baseline means the line defining the...

  3. 33 CFR 2.20 - Territorial sea baseline.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Territorial sea baseline. 2.20 Section 2.20 Navigation...JURISDICTION Jurisdictional Terms § 2.20 Territorial sea baseline. Territorial sea baseline means the line defining the...

  4. 33 CFR 2.20 - Territorial sea baseline.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Territorial sea baseline. 2.20 Section 2.20 Navigation...JURISDICTION Jurisdictional Terms § 2.20 Territorial sea baseline. Territorial sea baseline means the line defining the...

  5. Carbon Cycle 2.0: Bill Collins: A future without CC2.0

    ScienceCinema

    Bill Collins

    2010-09-01

    Bill Collins speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 1, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

  6. Solar Fuels and Carbon Cycle 2.0 (Carbon Cycle 2.0)

    ScienceCinema

    Alivisatos, Paul

    2011-06-03

    Paul Alivisatos, LBNL Director speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 4, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

  7. A Review of X-ray Diagnostic Calibrations in the 2 to 100 keV Region Using the High Energy X-ray Calibration Facility (HEX)

    SciTech Connect

    Ali, Zaheer; Pond, T; Buckles, R A; Maddox, B R; Chen, C D; DeWald, E L; Izumi, N; Stewart, R

    2010-05-19

    The precise and accurate measurement of X-rays in the 2 keV to 100 keV region is crucial to the understanding of HED plasmas and warm dense matter in general. With the emergence of inertially confined plasma facilities as the premier platforms for ICF, laboratory astrophysics, and national security related plasma experiments, the need to calibrate diagnostics in the high energy X-ray regime has grown. At National Security Technologies High Energy X-ray Calibration Facility (HEX) in Livermore, California, X-ray imagers, filter-fluorescer spectrometers, crystal spectrometers, image plates, and nuclear diagnostics are calibrated. The HEX can provide measurements of atomic line radiation, X-ray flux (accuracy within 10%), and X-ray energy (accuracy within 1%). The HEX source is comprised of a commercial 160 kV X-ray tube, a fluorescer wheel, a filter wheel, and a lead encasement. The X-ray tube produces a Tungsten bremsstrahlung spectrum which causes a foil to fluoresce line radiation. To minimize bremsstrahlung in the radiation for calibration we also provide various foils as filters. For experimental purposes, a vacuum box capable of 10{sup -7} Torr, as well as HPGe and CdTe radiation detectors, are provided on an optical table. Most geometries and arrangements can be changed to meet experimental needs.

  8. PHOEBE 2.0 - Where no model has gone before

    NASA Astrophysics Data System (ADS)

    Degroote, P.; Conroy, K.; Hambleton, K.; Bloemen, S.; Pablo, H.; Giammarco, J.; Prša, A.

    2013-02-01

    phoebe 2.0 is an open source framework bridging the gap between stellar observations and models. It allows to create and fit models simultaneously and consistently to a wide range of observational data such as photometry, spectroscopy, spectrapolarimetry, interferometry and astrometry. To reach the level of precision required by the newest generation of instruments such as Kepler, GAIA and the arrays of large telescopes, the code is set up to handle a wide range of phenomena such as multiplicity, rotation, pulsations and magnetic fields, and to model the involved physics to a new level.

  9. 36 CFR 222.2 - Management of the range environment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Management of the range environment. 222.2 Section 222.2 Parks, Forests, and Public...National Forest System § 222.2 Management of the range environment. (a) Allotments will be designated on the...

  10. 36 CFR 222.2 - Management of the range environment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Management of the range environment. 222.2 Section 222.2 Parks, Forests, and Public...National Forest System § 222.2 Management of the range environment. (a) Allotments will be designated on the...

  11. 36 CFR 222.2 - Management of the range environment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Management of the range environment. 222.2 Section 222.2 Parks, Forests, and Public...National Forest System § 222.2 Management of the range environment. (a) Allotments will be designated on the...

  12. 36 CFR 222.2 - Management of the range environment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Management of the range environment. 222.2 Section 222.2 Parks, Forests, and Public...National Forest System § 222.2 Management of the range environment. (a) Allotments will be designated on the...

  13. Metrological characterization of optical confocal sensors measurements (20 and 350 travel ranges)

    NASA Astrophysics Data System (ADS)

    Nouira, H.; El-Hayek, N.; Yuan, X.; Anwer, N.; Salgado, J.

    2014-03-01

    Confocal sensors are usually used in dimensional metrology applications, like roughness, form, thickness and surface profile measurements. With the progress of technologies, metrological applications require measurements with nanometer-level of accuracy by using ultra-high precision machines, which should present a minimum and stable metrology loop. The loop is equipped with sensors with nanometer-level of resolution and linear residual. The study presented here, is mainly focused on the characterization of Confocal sensors in order to identify their performance practically. Such information is useful to establish a correction model in the digital signal processing (DSP) software. In this context, LNE developed an ultra-high-precision machine, dedicated to the roughness measurement with an uncertainty of a few nanometres (< 30 nm) by using a tactile sensor. In order to match this machine to Confocal sensors, an experiment has been recently developed to characterize the behaviour of two commercial Confocal sensors with the measuring range of 20 ?m and 350 ? m. The experiment permits the evaluation of the major error sources: axial and radial motion errors as-well-as the deviation/tilt of the sensors.

  14. 20 CFR 418.1115 - What are the modified adjusted gross income ranges?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...What are the modified adjusted gross income ranges? 418.1115 Section 418.1115 Employees...What are the modified adjusted gross income ranges? (a) We list the modified adjusted gross income ranges for the calendar years 2011...

  15. 20 CFR 418.1115 - What are the modified adjusted gross income ranges?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...What are the modified adjusted gross income ranges? 418.1115 Section 418.1115 Employees...What are the modified adjusted gross income ranges? (a) The 2007 modified adjusted gross income ranges for each Federal tax filing...

  16. 20 CFR 418.1115 - What are the modified adjusted gross income ranges?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...What are the modified adjusted gross income ranges? 418.1115 Section 418.1115 Employees...What are the modified adjusted gross income ranges? (a) The 2007 modified adjusted gross income ranges for each Federal tax filing...

  17. 20 CFR 418.2115 - What are the modified adjusted gross income ranges?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...What are the modified adjusted gross income ranges? 418.2115 Section 418.2115 Employees...What are the modified adjusted gross income ranges? (a) We list the modified adjusted gross income ranges for the calendar years 2011...

  18. 20 CFR 418.2115 - What are the modified adjusted gross income ranges?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...What are the modified adjusted gross income ranges? 418.2115 Section 418.2115 Employees...What are the modified adjusted gross income ranges? (a) We list the modified adjusted gross income ranges for the calendar years 2011...

  19. 20 CFR 418.2115 - What are the modified adjusted gross income ranges?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...What are the modified adjusted gross income ranges? 418.2115 Section 418.2115 Employees...What are the modified adjusted gross income ranges? (a) We list the modified adjusted gross income ranges for the calendar years 2011...

  20. 20 CFR 418.2115 - What are the modified adjusted gross income ranges?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...What are the modified adjusted gross income ranges? 418.2115 Section 418.2115 Employees...What are the modified adjusted gross income ranges? (a) We list the modified adjusted gross income ranges for the calendar years 2011...

  1. 20 CFR 418.1115 - What are the modified adjusted gross income ranges?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...What are the modified adjusted gross income ranges? 418.1115 Section 418.1115 Employees...What are the modified adjusted gross income ranges? (a) The 2007 modified adjusted gross income ranges for each Federal tax filing...

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

    PubMed

    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. PMID:22086320

  3. W3C: XHTML 2.0

    NSDL National Science Digital Library

    2005-01-01

    Web developers will be especially interested in this sneak peek at the next incarnation of the Extensible HyperText Markup Language (XHTML). This is the seventh working draft of the XHTML 2.0 specification produced by the World Wide Web Consortium, an organization that creates standards that maintain interoperability. As can be seen from the list of issues, many unresolved points remain in the specification. However, the progress that has already been made is well documented and shows how the language is evolving.

  4. UQTk version 2.0 user manual.

    SciTech Connect

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

    2013-10-01

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

  5. The 20 element HgI2 energy dispersive x ray array detector system

    NASA Astrophysics Data System (ADS)

    Iwanczyk, J. A.; Dorri, N.; Wang, M.; Szczebiot, R. W.; Dabrowski, A. J.; Hedman, B.; Hodgson, K. O.; Patt, B. E.

    1991-11-01

    This paper describes recent progress in the development of HgI2 energy dispersive x-ray detector arrays and associated miniaturized processing electronics for synchrotron radiation research applications. The experimental results with a 20 element array detector were obtained under realistic synchrotron beam conditions at SSRL. An energy resolution of 250 eV (FWHM) at 5.9 keV (Mn-K(sub a)) was achieved. Energy resolution and throughput measurements versus input count rate and energy of incoming radiation have been measured. Extended X-ray Absorption Fine Structure (EXAFS) spectra were taken from diluted samples simulating proteins with nickel.

  6. Constraints on 3.55 keV line emission from stacked observations of dwarf spheroidal galaxies

    E-print Network

    D. Malyshev; A. Neronov; D. Eckert

    2014-08-15

    Several recent works have reported the detection of an unidentified X-ray line at 3.55 keV, which could possibly be attributed to the decay of dark matter (DM) particles in the halos of galaxy clusters and in the M31 galaxy. We analyze all publicly-available XMM-Newton data of dwarf spheroidal galaxies to test the possible DM origin of the line. Dwarf spheroidal galaxies have high mass-to-light ratios and their interstellar medium is not a source of diffuse X-ray emission, thus they are expected to provide the cleanest DM decay line signal. Our analysis shows no evidence for the presence of the line in the stacked spectra of the dwarf galaxies. It excludes the sterile neutrino DM decay origin of the 3.5 keV line reported by Bulbul et al. (2014) at the level of 4.6 sigma under standard assumptions about the Galactic DM column density in the direction of selected dwarf galaxies and at the level of 3.3 sigma assuming minimal Galactic DM column density. As a by-product of our analysis, we provide updated upper limits to the mixing angle of sterile neutrino DM in the mass range between 2 and 20 keV.

  7. Liquid helium cryostat with internal fluorescence detection for x-ray absorption studies in the 2–6 keV energy region

    PubMed Central

    Holman, Karen L. McFarlane; Latimer, Matthew J.; Yachandra, Vittal K.

    2014-01-01

    X-ray absorption spectroscop (XAS) in the intermediate x-ray region (2–6 keV) for dilute biological samples has been limited because of detector/flux limitations and inadequate cryogenic instrumentation. We have designed and constructed a new tailpiece/sample chamber for a commercially available liquid helium cooled cryostat which overcomes difficulties related to low fluorescence signals by using thin window materials and incorporating an internal photodiode detector. With the apparatus, XAS data at the Cl, S, and Ca K edges have been collected on frozen solutions and biological samples at temperatures down to 60 K. A separate chamber has been incorporated for collecting room-temperature spectra of standard compounds (for energy calibration purposes) which prevents contamination of the cryostat chamber and allows the sample to remain undisturbed, both important concerns for studying dilute and radiation-sensitive samples. PMID:25057214

  8. Single- and two-centre effects in fully differential cross sections for single ionization of H2 molecules by 75 keV protons

    NASA Astrophysics Data System (ADS)

    Ciappina, M. F.; Tachino, C. A.; Rivarola, R. D.; Sharma, S.; Schulz, M.

    2015-06-01

    We present theoretical calculations of single ionization of H2 molecules by 75 keV proton impact. The computed fully differential cross sections for different electron ejection geometries and projectile kinematical conditions are compared with recent measurements made by Hasan et al (2014 J. Phys. B: At. Mol. Opt. Phys. 47 215201). We employ a molecular version of the continuum distorted wave-eikonal initial state model, where all the interactions present in the exit channel are considered on an equal footing. In addition, our approach allows us to incorporate different interference terms and to assess their influence. Overall, the agreement between experiment and theory is better than for the case of more sophisticated schemes for coplanar geometries.

  9. Characterization of the PILATUS photon-counting pixel detector for X-ray energies from 1.75 keV to 60 keV

    NASA Astrophysics Data System (ADS)

    Donath, T.; Brandstetter, S.; Cibik, L.; Commichau, S.; Hofer, P.; Krumrey, M.; Lüthi, B.; Marggraf, S.; Müller, P.; Schneebeli, M.; Schulze-Briese, C.; Wernecke, J.

    2013-03-01

    The PILATUS detector module was characterized in the PTB laboratory at BESSY II comparing modules with 320 ?m thick and newly developed 450 ?m and 1000 ?m thick silicon sensors. Measurements were carried out over a wide energy range, in-vacuum from 1.75 keV to 8.8 keV and in air from 8 keV to 60 keV. The quantum efficiency (QE) was measured as a function of energy and the spatial resolution was measured at several photon energies both in terms of the modulation transfer function (MTF) from edge profile measurements and by directly measuring the point spread function (PSF) of a single pixel in a raster scan with a pinhole beam. Independent of the sensor thickness, the measured MTF and PSF come close to those for an ideal pixel detector with the pixel size of the PILATUS detector (172 × 172 ?m2). The measured QE follows the values predicted by calculation. Thicker sensors significantly enhance the QE of the PILATUS detectors for energies above 10 keV without impairing the spatial resolution and noise-free detection. In-vacuum operation of the PILATUS detector is possible at energies as low as 1.75 keV.

  10. A cryogenic electrostatic trap for long-time storage of keV ion beams

    NASA Astrophysics Data System (ADS)

    Lange, M.; Froese, M.; Menk, S.; Varju, J.; Bastert, R.; Blaum, K.; López-Urrutia, J. R. Crespo; Fellenberger, F.; Grieser, M.; von Hahn, R.; Heber, O.; Kühnel, K.-U.; Laux, F.; Orlov, D. A.; Rappaport, M. L.; Repnow, R.; Schröter, C. D.; Schwalm, D.; Shornikov, A.; Sieber, T.; Toker, Y.; Ullrich, J.; Wolf, A.; Zajfman, D.

    2010-05-01

    We report on the realization and operation of a fast ion beam trap of the linear electrostatic type employing liquid helium cooling to reach extremely low blackbody radiation temperature and residual gas density and, hence, long storage times of more than 5 min which are unprecedented for keV ion beams. Inside a beam pipe that can be cooled to temperatures <15 K, with 1.8 K reached in some locations, an ion beam pulse can be stored at kinetic energies of 2-20 keV between two electrostatic mirrors. Along with an overview of the cryogenic trap design, we present a measurement of the residual gas density inside the trap resulting in only 2×103 cm-3, which for a room temperature environment corresponds to a pressure in the 10-14 mbar range. The device, called the cryogenic trap for fast ion beams, is now being used to investigate molecules and clusters at low temperatures, but has also served as a design prototype for the cryogenic heavy-ion storage ring currently under construction at the Max-Planck Institute for Nuclear Physics.

  11. IBM Communications Sector Web 2.0 Meets Telecom

    E-print Network

    IBM Communications Sector Web 2.0 Meets Telecom Marty Slatnick, Telecom Solutions Labs IBM Global Technology Analyst IBM Software Group #12;Web 2.0 Meets Telecom Page 2 Executive summary Communications-generated insight--collaboration 20 Conclusion 21 For more information #12;Web 2.0 Meets Telecom Page 3 User

  12. Web 2.0 and Critical Information Literacy

    ERIC Educational Resources Information Center

    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…

  13. A Future with (out) Carbon Cycle 2.0 (Carbon Cycle 2.0)

    ScienceCinema

    Collins, Bill

    2011-06-08

    Bill Collins, Head of LBNL's Climate Sciences Department, speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 1, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

  14. A Call to Action: Carbon Cycle 2.0 (Carbon Cycle 2.0)

    ScienceCinema

    Alivisatos, Paul

    2011-06-08

    Berkeley Lab Director Paul Alivisatos speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 1, 2010. Humanity emits more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences.Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

  15. XPS analysis on chemical states of Li 4SiO 4 irradiated by 3 keV D2+

    NASA Astrophysics Data System (ADS)

    Luo, Tianyong

    2011-01-01

    Li 4SiO 4 will be applied as tritium breeding materials in future fusion reactor. The release behavior of tritium from neutron-irradiated Li 4SiO 4 should be sensitive to the chemical states of lithium, oxygen and silicon on the surface of Li 4SiO 4 with irradiated defects. The present study is focused on the influence of hydrogen isotopes and irradiation defects on surface chemical state of Li 4SiO 4. The X-ray Photoelectron Spectroscopy (XPS) was compared between non-irradiated Li 4SiO 4 and D2+-irradiated one. It was observed by that the binding energy (BE) of electron for Li-1s, O-1s and Si-2p of non-irradiated Li 4SiO 4 were 60.9 eV, 536.1 eV and 107.1 eV respectively. However new XPS peak for Li-1s at 57.2 eV, three XPS peaks for O-1s (at 536.1 eV, 533.2 eV and 531.3 eV, respectively) and three XPS peaks for Si-2p (at 107.1 eV, 104.2 eV and 99.7 eV, respectively) were observed in D2+-irradiated Li 4SiO 4. It is considered that the XPS peaks of 531.3 eV and 104.2 eV should be corresponding to O-1s and Si-2p in -Si-O-D while the XPS peak of 533.2 eV should be corresponding to O-1s in D-O-D. The formation of -Si-O-D and D-O-D is considered to be due to typical irradiated defects (lithium vacancy, silicon vacancy and implanted deuterium) induced by D2+-irradiation.

  16. Differential cross sections for scattering of 0.5-, 1.5-, and 5.0-keV hydrogen atoms by He, H2, N2, and O2

    NASA Technical Reports Server (NTRS)

    Newman, J. H.; Chen, Y. S.; Smith, K. A.; Stebbings, R. F.

    1986-01-01

    This paper reports measurements of absolute cross sections, differential in angle, for scattering of 0.5-, 1.5-, and 5.0-keV hydrogen atoms by He, H2, N2, and O2 at laboratory scattering angles between 0.1 and 5 deg. The measured cross sections are the sums of those for elastic and inelastic collisions having a fast H atom product and are needed for calculating energy transfer to the upper atmosphere from precipitating ring current particles.

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

    NASA Technical Reports Server (NTRS)

    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.

  18. GoBox 2.0

    NSDL National Science Digital Library

    This application, produced by GoBox Software, allows users to access numerous search engines, find home and business phone numbers, and get stock quotes quickly. Essentially, the application is a small box that resides on the computer screen from which users can type in their search terms, along with selecting which particular search engine they would like to use. Additionally, GoBox checks to make sure users are online and allows for fully customizable searches. Perhaps the best thing about GoBox is the fact that it takes up a relatively small amount of screen space. GoBox 2.0 is fully compatible with the Windows 98, Me, NT, 2000, and XP operating systems.

  19. The Effect of an External Magnetic Field on L X-ray Intensity Ratios for Elements in the Range 73? Z? 92 at 59.54 keV

    NASA Astrophysics Data System (ADS)

    Demir, Demet; ?ahin, Yusuf

    2007-11-01

    The L shell x-ray intensity ratios L?/Ll, L?/L?, and L?/L? for Ta, W, Au, Hg, Tl, Pb, Bi, Th, and U have been measured using the 59.54 keV incident photon energy in the external magnetic field of intensities ± 0.15, ± 0.45, and ± 0.75 T. A comparison is made of the experimental values obtained for B=0 with calculated values using theoretical x-ray emission rates, subshell ionization cross sections, subshell fluorescence yields and Coster-Kronig transitions probabilities. In the absence of external magnetic field, a fairly agreement is observed between experimental and theoretical values.

  20. Energy dependent response of the Fricke gel dosimeter prepared with 270 Bloom gelatine for photons in the energy range 13.93 keV-6 MeV

    NASA Astrophysics Data System (ADS)

    Cavinato, C. C.; Campos, L. L.

    2010-07-01

    The spectrophotometric energy dependent response to photons with effective energies between 13.93 keV and 6 MeV of the Fricke xylenol gel (FXG) dosimeter developed at IPEN, prepared using 270 Bloom gelatine, was evaluated in order to verify the possible dosimeter application in other medicine areas in addition to radiosurgery, for example, breast radiotherapy and blood bags radiosterilization. Other dosimetric characteristics were also evaluated. The obtained results indicate that the FXG dosimeter can contribute to dosimetry in different medical application areas including magnetic resonance imaging (MRI) evaluation technique that permits three-dimensional (3D) dose distribution evaluation.

  1. 2. GENERAL VIEW OF BRIDGE FROM ROADBED WITH 4' RANGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. GENERAL VIEW OF BRIDGE FROM ROADBED WITH 4' RANGE POLE NEAR NORTHWEST CORNER OF BRIDGE, LOOKING SOUTH - North Fork Bridge, Spans North Fork of White River at State Highway 5, Norfork, Baxter County, AR

  2. 2. GENERAL VIEW WITH 4' RANGE POLE AT SOUTHWEST CORNER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. GENERAL VIEW WITH 4' RANGE POLE AT SOUTHWEST CORNER OF APPROACH CONCRETE RAILING, LOOKING NORTHEAST - St. Louis - San Francisco Bridge, Spanning Spring River at U.S. Highway 62, Imboden, Lawrence County, AR

  3. Recent plant studies using Victoria 2.0

    SciTech Connect

    BIXLER,NATHAN E.; GASSER,RONALD D.

    2000-03-08

    VICTORIA 2.0 is a mechanistic computer code designed to analyze fission product behavior within the reactor coolant system (RCS) during a severe nuclear reactor accident. It provides detailed predictions of the release of radioactive and nonradioactive materials from the reactor core and transport and deposition of these materials within the RCS and secondary circuits. These predictions account for the chemical and aerosol processes that affect radionuclide behavior. VICTORIA 2.0 was released in early 1999; a new version VICTORIA 2.1, is now under development. The largest improvements in VICTORIA 2.1 are connected with the thermochemical database, which is being revised and expanded following the recommendations of a peer review. Three risk-significant severe accident sequences have recently been investigated using the VICTORIA 2.0 code. The focus here is on how various chemistry options affect the predictions. Additionally, the VICTORIA predictions are compared with ones made using the MELCOR code. The three sequences are a station blackout in a GE BWR and steam generator tube rupture (SGTR) and pump-seal LOCA sequences in a 3-loop Westinghouse PWR. These sequences cover a range of system pressures, from fully depressurized to full system pressure. The chief results of this study are the fission product fractions that are retained in the core, RCS, secondary, and containment and the fractions that are released into the environment.

  4. GaN\\/AlGaN heterojunction infrared detector responding in 8-14 and 20-70 mum ranges

    Microsoft Academic Search

    G. Ariyawansa; M. B. M. Rinzan; M. Strassburg; N. Dietz; A. G. U. Perera; S. G. Matsik; A. Asghar; I. T. Ferguson; H. Luo; H. C. Liu

    2006-01-01

    A GaN\\/AlGaN heterojunction interfacial work function internal photoemission infrared detector responding in 8-14 and 20-70 mum ranges has been demonstrated. Free carrier absorption based photoresponse shows a wavelength threshold of 14 mum with a peak responsivity of 0.6 mA\\/W at 80 K under -0.5 V bias. A sharp peak in the 11-13.6 mum range is observed superimposed on the free

  5. Enabling Problem Based Learning through Web 2.0 Technologies: PBL 2.0

    ERIC Educational Resources Information Center

    Tambouris, Efthimios; Panopoulou, Eleni; Tarabanis, Konstantinos; Ryberg, Thomas; Buus, Lillian; Peristeras, Vassilios; Lee, Deirdre; Porwol, Lukasz

    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, how we learn. Facilitating learning through the use of ICT, also known as eLearning, is a vital part of modern educational systems. Established pedagogical…

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

    ERIC Educational Resources Information Center

    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…

  7. NATIONAL WATER POLLUTION CONTROL ASSESSMENT MODEL, VERSION 2.0 (NWPCAM 2.0)

    EPA Science Inventory

    NWPCAM 2.0 is a national-level water quality modeling system that can be used to simulate the water quality changes and economic benefits that result from various pollution control policies. It builds and significantly improves on an earlier model the Clean Water Act Effects Mode...

  8. version 2.0 Improved result for helium 2 3

    E-print Network

    Pachucki, Krzysztof

    version 2.0 Improved result for helium 2 3 S 1 ionization energy Krzysztof Pachucki #3; Institute of relativistic and quantum electrodynamic e#11;ects to order m#11; 6 on the energy of the 2 3 S 1 state in helium Typeset using REVT E X #3; E-mail address: krp@fuw.edu.pl 1 #12; The helium atom is one of the simplest

  9. Measurements of complex permittivity of microwave substrates in the 20 to 300 K temperature range from 26.5 to 40.0 GHz

    Microsoft Academic Search

    Felix A. Miranda; William L. Gordon; Vernon O. Heinen; Ben T. Ebihara; Kul B. Bhasin

    1990-01-01

    A knowledge of the dielectric properties of microwve substrates at low temperatures is useful in the design of superconducting microwave circuits. Results are reported for a study of the complex permittivity of sapphire (Al2O3), magnesium oxide (MgO), silicon oxide (SiO2), lanthanum aluminate (LaAlO3), and zirconium oxide (ZrO2), in the 20 to 300 Kelvin temperature range, at frequencies from 26.5 to

  10. Measurements of complex permittivity of microwave substrates in the 20 to 300 K temperature range from 26.5 to 40.0 GHz

    Microsoft Academic Search

    Felix A. Miranda; William L. Gordon; Vernon O. Heinen; Ben T. Ebihara; Kul B. Bhasin

    1989-01-01

    A knowledge of the dielectric properties of microwave substrates at low temperatures is useful in the design of superconducting microwave circuits. Results are reported for a study of the complex permittivity of sapphire (Al2O3), magnesium oxide (MgO), silicon oxide (SiO2), lanthanum aluminate (LaAlO3), and zirconium oxide (ZrO2), in the 20 to 300 Kelvin temperature range, at frequencies from 26.5 to

  11. Solar Advisor Model User Guide for Version 2.0

    SciTech Connect

    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.

  12. Measurement of the polarization resulting from the scattering of 1250-keV gamma rays from bound electrons in lead 

    E-print Network

    Hamilton, Michael Clinton

    1966-01-01

    keV 12 Range of Angular Acceptance d&& for the 600-keV Region 35 13 Range of Angular Acceptance 68 for the 900-keV Region 36 14 Percent Polarization of Gamma Rays Resulting from the Scattering of 1250-keV Gamma Rays through 90' from Lead . 37... Measurement of S' to be Used with the Measure- ment for 1250-keV Gamma Rays Scattered through 90' in the 900-keV Region 40 IV Measurement of S for 600-keV Photons Resulting from the Scattering of 1250-keV Gamma Rays through 56' by Aluminum 41 V...

  13. USDA Career Intern Program Application file:///C|/Documents%20and%20Settings/tricia.dunfee/Desktop/USDA%20Career%20Intern%20Program%20Application.htm[8/3/2009 2:17:56 PM

    E-print Network

    Ma, Lena

    for 10-Point Veteran's Preference, or Department of Defense or Department of Veterans Affairs/tricia.dunfee/Desktop/USDA%20Career%20Intern%20Program%20Application.htm[8/3/2009 2:17:56 PM] U.S. Department of Agriculture documentation as appropriate.) PART B. EDUCATIONAL BACKGROUND 11. NAME AND ADDRESS OF COLLEGE OR UNIVERSITY

  14. Merged Sounding VAP Version 2.0

    SciTech Connect

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

    2010-03-15

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

  15. SolarSpeeder Solaroller 2.0SolarSpeeder Solaroller 2.0SolarSpeeder Solaroller 2.0 Skill Level

    E-print Network

    Lozano-Nieto, Albert

    , and simple, the SolarSpeeder is an easy project that uses the sun to power the fastest electronic solar car. Solaroller racing has two solar-powered cars race side-by-side down a one meter (3.3 foot) track. EarlySolarSpeeder Solaroller 2.0SolarSpeeder Solaroller 2.0SolarSpeeder Solaroller 2.0 Ltd

  16. r-Java 2.0: the nuclear physics

    E-print Network

    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...

  17. Measurement of LAGEOS-2 rotation by satellite laser ranging observations

    Microsoft Academic Search

    G. Bianco; M. Chersich; R. Devoti; V. Luceri; M. Selden

    2001-01-01

    The unprecedented single shot precision of the new-born Matera Laser Ranging Observatory (MLRO), that can reach a scattering down to a few millimeters on LA-GEOS orbit, discloses new chances in studying the high frequency dynamics. In this work we present the very first LAGEOS-2 observations in terms of range residuals and discuss the cause of the high frequencies noticed since

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

    PubMed Central

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

    2013-01-01

    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

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

    E-print Network

    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.

  20. Chemical evolution of frozen methane by keV ion bombardment

    Microsoft Academic Search

    G. Foti; L. Calcagno; F. Z. Zhou; G. Strazzulla

    1987-01-01

    Frozen methane layers at low temperature (~10 K) have been irradiated with high energy ion beams (keV Ar+ and He+). Molecular emission of H2, CH4, C2H2, C2H4 and C2H6 has been detected as a function of ion fluence in the range 1014 ions\\/cm2. Most of the original carbon atoms are bound after ion bombardment to form a hydrogenated amorphous carbon

  1. GEM Building Taxonomy (Version 2.0)

    USGS Publications Warehouse

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

    2013-01-01

    /7/8/IRRE9/10/RSH3+RWO211/FW12/13/ which can be read as (1) Direction = [DX or DY] (the building has the same lateral load-resisting system in both directions); (2) Material = [Unreinforced Masonry + solid fired clay bricks + cement: lime mortar]; (3) Lateral Load-Resisting System = [Wall]; (4) Date of construction = [pre-1939]; (5) Heaight = [exactly 2 storeys]; (6) Occupancy = [residential, unknown type]; (7) Building Position = [unknown = no entry]; (8) Shape of building plan = [unknown = no entry]; (9) Structural irregularity = [regular]; (10) Exterior walls = [unknown = no entry]; (11) Roof = [Shape: pitched and hipped, Roof covering: clay tiles, Roof system material: wood, Roof system type: wood trusses]; (12) Floor = [Floor system: Wood, unknown]; (13) Foundation = [unknown = no entry]. Mapping of GEM Building Taxonomy to selected taxonomies is included in the report -- for example, the above building would be referenced by previous structural taxonomies as: PAGER-STR as UFB or UFB4, by the World Housing Encyclopedia as 7 or 8 and by the European Macroseismic Scale (98) as M5. The Building Taxonomy data model is highly flexible and has been incorporated within a relational database architecture. Due to its ability to represent building typologies using a shorthand form, it is also possible to use the taxonomy for non-database applications, and we discuss possible application of adaptation for Building Information Modelling (BIM) systems, and for the insurance industry. The GEM Building Taxonomy was independently evaluated and tested by the Earthquake Engineering Research Institute (EERI), which received 217 TaxT reports from 49 countries, representing a wide range of building typologies, including single and multi-storey buildings, reinforced and unreinforced masonry, confined masonry, concrete, steel, wood, and earthern buildings used for residential, commercial, industrial, and educational occupancy. Based on these submissions and other feedback, the EERI team validated that the GEM Building Taxonomy is highly functional, robust and able to describe different buildings aroun

  2. Web 2.0 and Health 2.0: Are You In?

    PubMed

    Felkey, Bill G

    2008-01-01

    With over 6 billion web pages, over $100 billion in online sales every year in the U.S. alone and the average growth rate of online purchasing exceeding 26% over the last 5 years, the Internet is a powerful business tool. Today's shopper sees your actual pharmacy location and your Internet presence as one and the same. One study showed that 82% of the consumers surveyed who had a single frustrating experience online with a retailer would not return to the site for future dealings. A bad experience online made 28% of those surveyed unlikely to return to the retail location of the business, and over 55% said a bad online experience would have a negative impact on their overall opinion of the retailer. Web 2.0 refers to the social networking applications of the internet, Health 2.0 to its special health applications. Taking your Internet presence to the 2.0 level must be balanced with all of the other demands you are facing-but be aware that it's happening all around you. PMID:23969714

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

    E-print Network

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

    2013-01-28

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

  4. Microcraters produced in brittle materials in the 1 to 20 km\\/s velocity range

    Microsoft Academic Search

    J. C. Mandeville

    1979-01-01

    Microcraters were produced in sodalime glass and fused quartz by polystyrene-divinylbenzene, aluminum, and iron projectiles with masses between 0.5 and 200 picograms and velocities between 0.5 and 15 km\\/sec. The experiments were done with a 1.5 MV vertical microparticle accelerator. For each projectile and target combination, craters were formed over a range of projectile velocities and masses. It is shown

  5. FIG. 2.Maps of the keV (R12) band sky in the six projections: (a) north Galactic pole with l \\ 0 down and longitude increasing clockwise; (b) south1 4Galactic pole with l \\ 0 up and longitude increasing counterclockwise; (cf ) the l \\ 0, l \\ 270, l \\ 180,

    E-print Network

    Wisconsin at Madison, University of

    FIG. 2.ÈMaps of the keV (R12) band sky in the six projections: (a) north Galactic pole with l \\ 0. SNOWDEN et al. (see 485, 127) PLATE 2 #12;FIG. 3.ÈSame as except for the keV (R45) bandFig. 2 3 4 SNOWDEN et al. (see 485, 127) PLATE 3 #12;FIG. 4.ÈSame as except for the 1.5 keV (R67) bandFig. 2 SNOWDEN et

  6. 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

    NASA Technical Reports Server (NTRS)

    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.

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

    SciTech Connect

    Furnish, M.D.

    1994-12-01

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

  8. QuakeSim 2.0

    NASA Technical Reports Server (NTRS)

    Donnellan, Andrea; Parker, Jay W.; Lyzenga, Gregory A.; Granat, Robert A.; Norton, Charles D.; Rundle, John B.; Pierce, Marlon E.; Fox, Geoffrey C.; McLeod, Dennis; Ludwig, Lisa Grant

    2012-01-01

    QuakeSim 2.0 improves understanding of earthquake processes by providing modeling tools and integrating model applications and various heterogeneous data sources within a Web services environment. QuakeSim is a multisource, synergistic, data-intensive environment for modeling the behavior of earthquake faults individually, and as part of complex interacting systems. Remotely sensed geodetic data products may be explored, compared with faults and landscape features, mined by pattern analysis applications, and integrated with models and pattern analysis applications in a rich Web-based and visualization environment. Integration of heterogeneous data products with pattern informatics tools enables efficient development of models. Federated database components and visualization tools allow rapid exploration of large datasets, while pattern informatics enables identification of subtle, but important, features in large data sets. QuakeSim is valuable for earthquake investigations and modeling in its current state, and also serves as a prototype and nucleus for broader systems under development. The framework provides access to physics-based simulation tools that model the earthquake cycle and related crustal deformation. Spaceborne GPS and Inter ferometric Synthetic Aperture (InSAR) data provide information on near-term crustal deformation, while paleoseismic geologic data provide longerterm information on earthquake fault processes. These data sources are integrated into QuakeSim's QuakeTables database system, and are accessible by users or various model applications. UAVSAR repeat pass interferometry data products are added to the QuakeTables database, and are available through a browseable map interface or Representational State Transfer (REST) interfaces. Model applications can retrieve data from Quake Tables, or from third-party GPS velocity data services; alternatively, users can manually input parameters into the models. Pattern analysis of GPS and seismicity data has proved useful for mid-term forecasting of earthquakes, and for detecting subtle changes in crustal deformation. The GPS time series analysis has also proved useful as a data-quality tool, enabling the discovery of station anomalies and data processing and distribution errors. Improved visualization tools enable more efficient data exploration and understanding. Tools provide flexibility to science users for exploring data in new ways through download links, but also facilitate standard, intuitive, and routine uses for science users and end users such as emergency responders.

  9. Cone Deck 2 Lot 20 Lot 21

    E-print Network

    Howitt, Ivan

    Mary Alexander Rd ander 51 41 8 546 502501 503 504 46 31 538 545 5 4a 4b 49 17 48 63 52 56 544 55a 23 Village North Deck Lot 20 Lot 19 32 Colvard 51 Robinson Hall 55a Facilities Management 546 Lynch Hall Lot

  10. Cone Deck 2 Lot 20 Lot 21

    E-print Network

    Howitt, Ivan

    Dr Mary Alexander Rd ander 51 41 8 546 502501 503 504 46 31 538 545 5 4a 4b 49 17 48 63 52 56 544 55a. Village Deck Lot 20 Lot 18 & 19 32 Colvard 80 PORTAL 55a Facilities Management 563 Hunt Hall Lot 21 Lot 23

  11. Differential scattering cross sections for collisions of 0.5-, 1.5-, and 5.0-keV helium atoms with He, H2, N2, and O2. [for atmospheric processes modeling

    NASA Technical Reports Server (NTRS)

    Newman, J. H.; Smith, K. A.; Stebbings, R. F.; Chen, Y. S.

    1985-01-01

    This paper reports the first results of an experimental program established to provide cross section data for use in modeling various atmospheric processes. Absolute cross sections, differential in the scattering angle, have been measured for collisions of 0.5-, 1.5-, and 5.0-keV helium atoms with He, H2, N2, and O2 at laboratory scattering angles between 0.1 deg and 5 deg. The results are the sums of cross sections for elastic and inelastic scattering of helium atoms; charged collision products are not detected. Integration of the differential cross section data yields integral cross sections consistent with measurements by other workers. The apparatus employs a position-sensitive detector for both primary and scattered particles and uses a short target cell with a large exit aperture to ensure a simple and well-defined apparatus geometry.

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

    SciTech Connect

    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.

  13. User Manual 2.0 Fluorometer

    E-print Network

    Uppsala Universitet

    ;2 Contents Product Contents...........................................................................................................3 Safety Information......................................................................5 Product Specifications

  14. Location of Lunakhod 2 from laser ranging observations

    NASA Technical Reports Server (NTRS)

    Mulholland, J. D.; Shelus, P. J.; Silverberg, E. C.

    1973-01-01

    Results of laser ranging attempts on Lunakhod 2 are presented. Laser ranging can only be accomplished at night, so only the straight-line distance between the end points of a daytime traverse can be determined. Uncertainties of positional determination are strongly dependent on the length of the tracking arc. The data, obtained in the first two lunar nights, are too sparse to yield reliable positional determinations. The results clearly illustrate the critical importance of a high-quality lunar ephemeris for the interpretation of sparse data.

  15. Fast neutron ineleastic scattering cross sections of /sup 238/U for states between 680 and 1530 keV

    SciTech Connect

    Shao, J.Q.; Couchell, G.P.; Egan, J.J.; Kegel, G.H.R.; Li, S.Q.; Mittler, A.; Pullen, D.J.; Schier, W.A.; Arthur, E.D.

    1986-03-01

    Neutron inelastic scattering cross sections for /sup 238/U levels between 680- and 1530-keV excitation energy have been measured in the incident neutron energy range from 0.9 to 2.2 MeV. The (n,n') time-of-flight (TOF) technique was used to obtain direct differential inelastic cross sections. Neutrons were generated using the /sup 7/Li(p,n)/sup 7/Be reaction. Experimental parameters were optimized to achieve an energy resolution of <15 keV. Level cross sections were deduced from the measured 125-deg differential scattering cross sections. The validity of this procedure was confirmed by measuring the angular distributions for nine levels at En=1.5 and 2.0 MeV. Background due to fission induced by fast neutrons was subtracted. The TOF spectra were unfolded using the method of the response function. The data were corrected for multiple scattering and neutron attenuation in disk scattering geometry using an analytic method. Theoretical calculations of the cross sections were carried out using reaction models appropriate to the description of compound nucleus and direct interaction processes. The data are compared to (n,n'..gamma..) results and the ENDF/B-V evaluation.

  16. Geometry 2.0 User's Manual 1

    E-print Network

    Sussman, Mark

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.6.1 Gas Bubble Bursting at a Free Surface . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.3.2 Making Movies with MatLab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 3.3.3 Synchronizing Movie Frames With Timesteps . . . . . . . . . . . . . . . . . . . . . 25 A Sample Inputs File 27 B

  17. 20 CFR 206.2 - Computation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...RAILROAD RETIREMENT ACT ACCOUNT BENEFITS RATIO § 206.2 Computation. (a... (1) Compute the account benefits ratios for each of the most recent 10 preceding...and (2) Certify the account benefits ratio for each such fiscal year to the...

  18. Development of a 20x20cm2 'hot' indium-alloy hermetic seal

    E-print Network

    1 Development of a 20x20cm2 'hot' indium-alloy hermetic seal in an inert atmosphere for photo Use indium alloys: - industry standard approach - soft metal - low melting point - essentially zero into the ceramic body and filled with indium alloy (InBi) Indium alloy wets copper surface and makes a strong Ni

  19. Embedding Web 2.0 Strategies in Learning and Teaching

    Microsoft Academic Search

    Vladlena Benson; Barry Avery

    Many researchers see Web 2.0 technologies as having the potential to transform e-learning and traditional teaching methods. Significant attention has been paid to the evaluation of some of the Web 2.0 tools in education, however an accepted pedagogical model has yet to emerge. Web 2.0 technologies have become an essential part of student lives, now educators are turning to them

  20. Towards a readiness model for health 2.0

    Microsoft Academic Search

    Payam Sadeghi; Craig Kuziemsky; Morad Benyoucef

    2011-01-01

    Enterprise 2.0 applications are changing the way organizations run their business, especially in terms of communication, information sharing and integration capabilities. With Enterprise 2.0, employees become knowledge workers equipped with social tools to better understand the business processes, the services and the customers they are involved with,. This paper explores potential areas for using Enterprise 2.0 in healthcare with the

  1. Evaluating HDR photos using Web 2.0 technology

    NASA Astrophysics Data System (ADS)

    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 indices with quantitative image statistics which may provide useful guidance for developing better tone mapping operators.

  2. Environmental Public Health Performance Standards (v 2.0)

    E-print Network

    Environmental Public Health Performance Standards (v 2.0) January 7, 2010 #12;Environmental Public.......................................................................................................................................................3 Essential Environmental Public Health Services Environmental Public Health Problems

  3. Fitness Fever and Fitness Fever 2.0 Requirements

    E-print Network

    Weber, David J.

    1 Fitness Fever and Fitness Fever 2.0 Requirements o Have a Body Mass Index (BMI) of 25 or greater Fever program, participants will receive o One Group Training Session and one Group Challenge a week Personal Training session #12;2 Circle one: Fitness Fever or Fitness Fever 2.0 Name Local Address Apt

  4. Energetic ion (>~50kev) and electron (>~40kev) bursts observed by ULYSSES near Jupiter

    Microsoft Academic Search

    G. C. Anagnostopoulos; A. Aggelis; I. Karanikola; P. K. Marhavilas

    2001-01-01

    A careful analysis of data collected by the HISCALE experiment on board Ulysses suggests that the quasi-periodic (Q-P) modulation of several or tens of minutes in flux and\\/or anisotropy\\/spectral observations is an almost permanent characteristic of the energetic (>~50 keV) ion population in the outer and the high latitude middle magnetosphere of Jupiter. In most cases a periodicity of ~5-20

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

    NASA Astrophysics Data System (ADS)

    Zhao, Y. L.; Lv, W. M.; Liu, Z. Q.; Zeng, S. W.; Motapothula, M.; Dhar, S.; Ariando, Wang, Q.; Venkatesan, T.

    2012-03-01

    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.

  6. 20 CFR 703.2 - Forms.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...substitute forms without OWCP's approval. Form No. Title (1) LS-271 Application for Self-Insurance. (2) LS-274 Report of Injury Experience. (3) LS-275 SI Self-Insurer's Agreement and Undertaking. (4)...

  7. 20 CFR 703.2 - Forms.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...substitute forms without OWCP's approval. Form No. Title (1) LS-271 Application for Self-Insurance. (2) LS-274 Report of Injury Experience. (3) LS-275 SI Self-Insurer's Agreement and Undertaking. (4)...

  8. 20 CFR 703.2 - Forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...substitute forms without OWCP's approval. Form No. Title (1) LS-271 Application for Self-Insurance. (2) LS-274 Report of Injury Experience. (3) LS-275 SI Self-Insurer's Agreement and Undertaking. (4)...

  9. 20 CFR 703.2 - Forms.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...substitute forms without OWCP's approval. Form No. Title (1) LS-271 Application for Self-Insurance. (2) LS-274 Report of Injury Experience. (3) LS-275 SI Self-Insurer's Agreement and Undertaking. (4)...

  10. 20 CFR 703.2 - Forms.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...substitute forms without OWCP's approval. Form No. Title (1) LS-271 Application for Self-Insurance. (2) LS-274 Report of Injury Experience. (3) LS-275 SI Self-Insurer's Agreement and Undertaking. (4)...

  11. Natural electromagnetic disturbances in 5-20 Hz frequency range in the F-layer and on the ground

    NASA Astrophysics Data System (ADS)

    Nosikova, Nataliya; Yagova, Nadia; Surkov, Vadim; Pilipenko, Vyacheslav; Schekotov, Alexander

    2013-04-01

    The quasi-periodical disturbances of natural geomagnetic field in the frequency range 5-20 Hz registered at CHAMP satellite are analyzed and compared with ground data. Occurrence rates of coherent signals in the ionosphere and at the ground at different frequencies are studied and a maximum near the first Schumann resonance frequency is found. However, no relation of observed 8 Hz signal in the F-layer with thunderstorm activity is seen andthe latitude distribution demonstrates a clear polar maximum. Different mechanisms for excitation of several Hz disturbances in the F-layer are discussed.

  12. An electrically driven terahertz metamaterial diffractive modulator with more than 20 dB of dynamic range

    SciTech Connect

    Karl, N.; Reichel, K.; Mendis, R.; Mittleman, D. M. [Department of Electrical and Computer Engineering, Rice University, MS 378, Houston, Texas 77251-1892 (United States); Chen, H.-T.; Taylor, A. J. [Center for Integrated Nanotechnologies, Los Alamos National Laboratory, P. O. Box 1663, MS K771, Los Alamos, New Mexico 87545 (United States); Brener, I.; Benz, A.; Reno, J. L. [Center for Integrated Nanotechnologies, Sandia National Laboratories, P. O. Box 5800, MS 1082, Albuquerque, New Mexico 87185 (United States)

    2014-03-03

    We design and experimentally demonstrate a switchable diffraction grating for terahertz modulation based on planar active metamaterials, where a Schottky gate structure is implemented to tune the metamaterial resonances in real-time via the application of an external voltage bias. The diffraction grating is formed by grouping the active split-ring resonators into an array of independent columns with alternate columns biased. We observe off-axis diffraction over a wide frequency band in contrast to the narrow-band resonances, which permits operation of the device as a relatively high-speed, wide-bandwidth, high-contrast modulator, with more than 20?dB of dynamic range.

  13. Full-range electrical characteristics of WS2 transistors

    NASA Astrophysics Data System (ADS)

    Kumar, Jatinder; Kuroda, Marcelo A.; Bellus, Matthew Z.; Han, Shu-Jen; Chiu, Hsin-Ying

    2015-03-01

    We fabricated transistors formed by few layers to bulk single crystal WS2 to quantify the factors governing charge transport. We established a capacitor network to analyze the full-range electrical characteristics of the channel, highlighting the role of quantum capacitance and interface trap density. We find that the transfer characteristics are mainly determined by the interplay between quantum and oxide capacitances. In the OFF-state, the interface trap density (<1012 cm-2) is a limiting factor for the subthreshold swing. Furthermore, the superior crystalline quality and the low interface trap density enabled the subthreshold swing to approach the theoretical limit on a back-gated device on SiO2/Si substrate.

  14. New and Innovative Library Services: Moving with Web 2.0 / Library 2.0 Technology, a Case Study

    NASA Astrophysics Data System (ADS)

    Sahu, H. K.; Pathak, S. K.; Singh, S. N.

    2010-10-01

    We give an overview and definition of Web 2.0 and Library 2.0 technology, especially addressing how it changes access to collections for users. We also describe its unlimited possibilities. The various components of Library 2.0 viz blogs, wikis, RSS, instant messaging, social networking, podcasting, and tagging are briefly summarized. Initiatives at three special information centers and libraries (IUCAA — Astronomy and Astrophysics; IIT — Science and Technology; and NIV — Viral Diseases) are described. We conclude with a futuristic view of Library 2.0.

  15. Measurements of complex permittivity of microwave substrates in the 20 to 300 K temperature range from 26. 5 to 40. 0 GHz

    SciTech Connect

    Miranda, F.A.; Gordon, W.L.; Heinen, V.O.; Ebihara, B.T.; Bhasin, K.B.

    1989-07-01

    A knowledge of the dielectric properties of microwave substrates at low temperatures is useful in the design of superconducting microwave circuits. Results are reported for a study of the complex permittivity of sapphire (Al{sub 2}O{sub 3}), magnesium oxide (MgO), silicon oxide (SiO{sub 2}), lanthanum aluminate (LaAlO{sub 3}), and zirconium oxide (ZrO{sub 2}), in the 20 to 300 Kelvin temperature range, at frequencies from 26.5 to 40.0 GHz. The values of the real and imaginary parts of the complex permittivity were obtained from the scattering parameters, which were measured using a HP-8510 automatic network analyzer. For these measurements, the samples were mounted on the cold head of a helium gas closed cycle refrigerator, in a specially designed vacuum chamber. An arrangement of wave guides, with mica windows, was used to connect the cooling system to the network analyzer. A decrease in the value of the real part of the complex permittivity of these substrates, with decreasing temperature, was observed. For MgO and Al{sub 2}O{sub 3}, the decrease from room temperature to 20 K was of 7 and 15 percent, respectively. For LaAlO{sub 3}, it decreased by 14%, for ZrO{sub 2} by 15%, and for SiO{sub 2} by 2%, in the above mentioned temperature range.

  16. Titanium Language Reference Manual Version 2.20

    E-print Network

    California at Irvine, University of

    Titanium Language Reference Manual Version 2.20 P. N. Hilfinger (editor), Dan Bonachea, Kaushik Berkeley, California 94720 #12;Titanium Language Reference Manual Version 2.20 P. N. Hilfinger (editor, and Katherine Yelick August, 2006 #12;Abstract The Titanium language is a Java dialect for high

  17. Road Safety 2.0: Insights and Implications for Government

    Microsoft Academic Search

    Dieter Fink

    2010-01-01

    This research provides insights to government into the potential of web 2.0 as a mechanism to engage with the public on issues concerning road safety. It uses the Transtheoretical Model of Change (TTM) to bring about citizen engagement. An important first step in TTM was to establish young people's 'contemplation' of engaging with government via web 2.0 by determining their

  18. Systems Engineering Leading Indicators Guide, Version 2.0

    E-print Network

    Lean Advancement Initiative

    2010-06-29

    The Systems Engineering Leading Indicators Guide editorial team is pleased to announce the release of Version 2.0. Version 2.0 supersedes Version 1.0, which was released in July 2007 and was the result of a project initiated ...

  19. Scenarios and Strategies for Web 2.0

    ERIC Educational Resources Information Center

    Martin, Graeme; Reddington, Martin; Kneafsey, Mary Beth; Sloman, Martyn

    2009-01-01

    Purpose: The aim of this article is to bring together ideas from the authors' review of the Web 2.0 literature, the data and their insights from this and other technology-related projects to produce a framework for strategies on Web 2.0 focusing on the implications for human resource professionals. Design/methodology/approach: The authors discuss…

  20. A Day in the Life of Web 2.0

    ERIC Educational Resources Information Center

    Warlick, David

    2006-01-01

    This article is an extended description of a hypothetical school in which student, teacher, media, and administrative activities are all linked together through the use of Web 2.0 technologies, from classroom wikis to text messaging. Through this description, the author conveys an image of how the multimedia tools of Web 2.0 may eventually change…

  1. Wisconsin ProgramIntegration System 2.0 Reference Manual

    E-print Network

    Reps, Thomas W.

    Wisconsin Program­Integration System 2.0 Reference Manual University of Wisconsin Madison, WI #12; WPIS 2.0 Reference Manual Copyright (c) 1993 by Thomas W. Reps and the University of Wisconsin, Madison permission from Thomas W. Reps, Computer Sciences Department, University of Wisconsin­Madison, 1210 W. Dayton

  2. Web 2.0 in the Mathematics Classroom

    ERIC Educational Resources Information Center

    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,…

  3. Culture, Learning Styles, and Web 2.0

    ERIC Educational Resources Information Center

    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…

  4. Information Literacy Instruction in the Web 2.0 Library

    ERIC Educational Resources Information Center

    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…

  5. Detecting OCL Traps in the UML 2.0 Superstructure

    E-print Network

    Gogolla, Martin - Fachbereich 3

    Detecting OCL Traps in the UML 2.0 Superstructure An Experience Report Hanna Bauerdick, Martin://www.db.informatik.uni-bremen.de Abstract. Currently, the OMG is developing a new version of the Uni- #12;ed Modeling Language (UML), UML 2.0, which involves major innova- tions in its metamodel. As for previous versions of the UML, the Object

  6. Herwig++ 2.0 beta release note.

    E-print Network

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

    @particle.uni-karlsruhe.de D. Grellscheid IPPP, Department of Physics, Durham University E-mail: david.grellscheid@durham.ac.uk A. Ribon PH Department, CERN E-mail: Alberto.Ribon@cern.ch P. Richardson IPPP, Department of Physics, Durham University E-mail: Peter... .1 Availability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 Hadron-Hadron Collisions 1 3 Other Changes 1 1 Introduction The last major public version (1.0) of Herwig++ was reported in detail in [1]. In this note we describe...

  7. NASA Taxonomy 2.0 Project Overview

    NASA Technical Reports Server (NTRS)

    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.

  8. 20 CFR 330.2 - Computation of daily benefit rate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    20 Employees' Benefits 1 2011-04-01 2011-04-01 false Computation of daily benefit rate. 330.2 Section 330.2 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT...

  9. 20 CFR 330.2 - Computation of daily benefit rate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    20 Employees' Benefits 1 2014-04-01 2012-04-01 true Computation of daily benefit rate. 330.2 Section 330.2 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE...

  10. 20 CFR 336.2 - Duration of normal unemployment benefits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    20 Employees' Benefits 1 2014-04-01 2012-04-01 true Duration of normal unemployment benefits. 336.2 Section 336.2 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT...

  11. 20 CFR 336.2 - Duration of normal unemployment benefits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    20 Employees' Benefits 1 2013-04-01 2012-04-01 true Duration of normal unemployment benefits. 336.2 Section 336.2 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT...

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

    NASA Astrophysics Data System (ADS)

    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 ?m2 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. Elevation-Dependent Temperature Trends in the Rocky Mountain Front Range: Changes over a 56- and 20-Year Record

    PubMed Central

    McGuire, Chris R.; Nufio, César R.; Bowers, M. Deane; Guralnick, Robert P.

    2012-01-01

    Determining the magnitude of climate change patterns across elevational gradients is essential for an improved understanding of broader climate change patterns and for predicting hydrologic and ecosystem changes. We present temperature trends from five long-term weather stations along a 2077-meter elevational transect in the Rocky Mountain Front Range of Colorado, USA. These trends were measured over two time periods: a full 56-year record (1953–2008) and a shorter 20-year (1989–2008) record representing a period of widely reported accelerating change. The rate of change of biological indicators, season length and accumulated growing-degree days, were also measured over the 56 and 20-year records. Finally, we compared how well interpolated Parameter-elevation Regression on Independent Slopes Model (PRISM) datasets match the quality controlled and weather data from each station. Our results show that warming signals were strongest at mid-elevations over both temporal scales. Over the 56-year record, most sites show warming occurring largely through increases in maximum temperatures, while the 20-year record documents warming associated with increases in maximum temperatures at lower elevations and increases in minimum temperatures at higher elevations. Recent decades have also shown a shift from warming during springtime to warming in July and November. Warming along the gradient has contributed to increases in growing-degree days, although to differing degrees, over both temporal scales. However, the length of the growing season has remained unchanged. Finally, the actual and the PRISM interpolated yearly rates rarely showed strong correlations and suggest different warming and cooling trends at most sites. Interpretation of climate trends and their seasonal biases in the Rocky Mountain Front Range are dependent on both elevation and the temporal scale of analysis. Given mismatches between interpolated data and the directly measured station data, we caution against an over-reliance on interpolation methods for documenting local patterns of climatic change. PMID:22970205

  14. Human Category Learning 2.0

    PubMed Central

    Ashby, F. Gregory; Maddox, W. Todd

    2010-01-01

    During the 1990’s and early 2000’s, cognitive neuroscience investigations of human category learning focused on the primary goal of showing that humans have multiple category learning systems and on the secondary goals of identifying key qualitative properties of each system and of roughly mapping out the neural networks that mediate each system. Many researchers now accept the strength of the evidence supporting multiple systems, and as a result, during the past few years, work has begun on the second generation of research questions – that is, on questions that begin with the assumption that humans have multiple category learning systems. This article reviews much of this second generation of research. Topics covered include: 1) How do the various systems interact? 2) Are there different neural systems for categorization and category representation? 3) How does automaticity develop in each system?, and 4) Exactly how does each system learn? PMID:21182535

  15. Energy Demand in China (Carbon Cycle 2.0)

    ScienceCinema

    Price, Lynn

    2011-06-08

    Lynn Price, LBNL scientist, speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 2, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

  16. Biofuels Science and Facilities (Carbon Cycle 2.0)

    ScienceCinema

    Keasling, Jay D

    2011-06-03

    Jay D. Keasling speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 2, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

  17. Carbon Cycle 2.0: Ashok Gadgil: global impact

    ScienceCinema

    Ashok Gadgi

    2010-09-01

    Ashok Gadgil speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 2, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

  18. BioCat 2.0

    SciTech Connect

    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.

  19. Oh! Web 2.0, Virtual Reference Service 2.0, Tools and Techniques (I): A Basic Approach

    ERIC Educational Resources Information Center

    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…

  20. Single- and double-charge-exchange cross sections for Ar{sup {ital q}+}+H{sub 2} ({ital q}=6, 7, 8, 9, and 11) collisions from 6 eV to 11 keV

    SciTech Connect

    Kravis, S.; Saitoh, H.; Okuno, K.; Soejima, K.; Kimura, M.; Shimamura, I.; Awaya, Y.; Kaneko, Y.; Oura, M.; Shimakura, N. [The Institute of Physical and Chemical Research (RIKEN), Hirosawa 2-1, Wako-shi, Saitama, 351-01 (Japan)] [The Institute of Physical and Chemical Research (RIKEN), Hirosawa 2-1, Wako-shi, Saitama, 351-01 (Japan); [Department of Physics, Tokyo Metropolitan University, Minami-Ohsawa 1-1, Hachioji-shi, Tokyo 192-03 (Japan); [Argonne National Laboratory, Argonne, Illinois 60439 (United States); [Faculty of Science, Niigata University, Niigata-shi, 950-21 (Japan)

    1995-08-01

    The cross sections for single-electron capture, including transfer ionization, and for double-electron capture, have been measured for Ar{sup {ital q}+}+H{sub 2} for {ital q}=6, 7, 8, 9, and 11 with projectile energies from {ital q} eV to {ital q} keV. Theoretically, the cross sections for Ar{sup 6+} and Ar{sup 8+} impact were calculated using a molecular-orbital expansion method in the energy region from 240 eV to 80 keV, and are in good agreement with experiment. The single-electron-capture cross sections were found to be more than one order of magnitude larger than those for double capture in both experiment and theory. The single-electron-capture cross sections were also compared to the Langevin cross section, a scaling law developed by Mueller and Salzborn [Phys. Lett. 62A, 391 (1977)], and the absorbing sphere model.

  1. Enabling the transition towards Earth Observation Science 2.0

    NASA Astrophysics Data System (ADS)

    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 applications and education.

  2. Combining 2-m temperature nowcasting and short range ensemble forecasting

    NASA Astrophysics Data System (ADS)

    Kann, A.; Haiden, T.; Wittmann, C.

    2011-12-01

    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 correction of the first and second moment (mean bias and dispersion) for Gaussian distributed continuous variables. Validation results indicate that all three methods produce sharp and reliable probabilistic 2-m temperature forecasts. However, the statistical and combined dynamic-statistical methods slightly outperform the pure dynamical approach, mainly due to the under-dispersive behavior of ALADIN-LAEF outside the nowcasting range. The training length does not have a pronounced impact on forecast skill, but a spread re-scaling improves the forecast skill substantially. Refinements of the statistical methods yield a slight further improvement.

  3. New interstellar molecular transitions in the 2 millimeter range

    SciTech Connect

    Hollis, J.M.; Snyder, L.E.; Blake, D.H.; Lovas, F.J.; Suenram, R.D.; Ulich, B.L.

    1981-12-15

    We derive a Sgr B2 kinetic temperature of approx.47 K based on previously unreported observations of K components of the 9/sub K/-8/sub K/ transition of CH/sub 3/CHH. We report 2 mm range observations in galactic molecular clouds of the 15/sub 5,11/-16/sub 4,12/ and 10/sub 0,10/-9/sub 1,9/ transitions of SO/sub 2/, the 3,4--2,3 transition of SO, the 4,3--3,3 transition of /sup 34/SO, the 11/sub 0/-11/sub -/1E, 8/sub 0/--8/sub -/1E, and 2/sub 1/--3/sub 0/A/sup +/ transition of CH/sub 3/OH, the 18/sub 2,17/--17/sub 2,16/ transition of CH/sub 3/CH/sub 2/CN, the 17--16 transition of HC/sub 3/N, and transitions of unidentified molecular species at frequencies of 144244.8, 145017.5/154583.0, 145075.9, 146932.5, 150328.0, 153431.0, 153487.5, 153668.3, and 159915.6 MHz. We searched for but did not detect the 14/sub 14,0/--13/sub 13,0/, 14/sub 14,1/--13/sub 13,1/, 15/sub 15,0/--14/sub 14,0/, and 15/sub 15,1/--14/sub 14,1/ transitions of H/sub 2/SO/sub 4/, the 25/sub 0,25/--24/sub 0,24/ and 25/sub 1,25/--24/sub 1,24/ transitions of HCOCHO, the 4--3 transition of HCP, the 7--6 transition of OC/sup 18/O, and the 2/sub 12/--1/sub 11/ and 2/sub 02/--1/sub 01/ transitions of HNO in several galactic molecular sources. We discuss the present evidence for the existence of interstellar HNO.

  4. The T2K Side Muon Range Detector (SMRD)

    NASA Astrophysics Data System (ADS)

    Aoki, S.; Barr, G.; Batkiewicz, M.; B?ocki, J.; Brinson, J. D.; Coleman, W.; D?browska, A.; Danko, I.; Dziewiecki, M.; Ellison, B.; Golyshkin, L.; Gould, R.; Hara, T.; Haremza, J.; Hartfiel, B.; Holeczek, J.; Izmaylov, A.; Khabibullin, M.; Khotjantsev, A.; Kie?czewska, D.; Kilinski, A.; Kisiel, J.; Kudenko, Y.; Kulkarni, N.; Kurjata, R.; Kutter, T.; ?agoda, J.; Liu, J.; Marzec, J.; Metcalf, W.; Metelko, C.; Mijakowski, P.; Mineev, O.; Naples, D.; Nauman, M.; Nicholls, T. C.; Northacker, D.; Nowak, J.; Noy, M.; Paolone, V.; Pearce, G. F.; Perevozchikov, O.; Posiada?a, M.; Przew?ocki, P.; Qian, W.; Raymond, M.; Reid, J.; Rondio, E.; Shabalin, E.; Siyad, M.; Smith, D.; Sobczyk, J.; Stodulski, M.; Sulej, R.; ?wierblewski, J.; Suzuki, A. T.; Szeg?owski, T.; Szeptycka, M.; Thorpe, M.; W?cha?a, T.; Warner, D.; Weber, A.; Yano, T.; Yershov, N.; Zalewska, A.; Zaremba, K.; Ziembicki, M.

    2013-01-01

    The T2K experiment is a long baseline neutrino oscillation experiment aiming to observe the appearance of ?e in a ?? beam. The ?? beam is produced at the Japan Proton Accelerator Research Complex (J-PARC), observed with the 295 km distant Super-Kamiokande Detector and monitored by a suite of near detectors at 280 m from the proton target. The near detectors include a magnetized off-axis detector (ND280) which measures the unoscillated neutrino flux and neutrino cross-sections. The present paper describes the outermost component of ND280 which is a Side Muon Range Detector (SMRD) composed of scintillation counters with embedded wavelength shifting fibers and Multi-Pixel Photon Counter readout. The components, performance and response of the SMRD are presented.

  5. Asymptotic normalization coefficients from the (20)Ne((3)He, d)(21)Na reaction and astrophysical factor for (20)Ne(p,gamma)(21)Na 

    E-print Network

    Mukhamedzhanov, AM; Bem, P.; Burjan, V.; Gagliardi, Carl A.; Irgaziev, BF; Kroha, V.; Novak, J.; Piskor, S.; Simeckova, E.; Tribble, Robert E.; Vesely, F.; Vincour, J.

    2006-01-01

    ] at proton energies of Ep #1; 400 keV and higher, substantially above the Gamow window. The proton partial width of the subthreshold resonance is determined by the asymptotic normalization coefficient (ANC) for 20Ne+ p? 21Na(1/2+, 2425 keV) [2]. The same...

  6. Nonmagnetic ground state in the cubic compounds PrNi2Cd20 and PrPd2Cd20

    NASA Astrophysics Data System (ADS)

    Yazici, D.; Yanagisawa, T.; White, B. D.; Maple, M. B.

    2015-03-01

    Temperature-dependent magnetization, specific-heat, and electrical-resistivity measurements were performed on single crystals of PrNi2Cd20 and PrPd2Cd20 . Neither compound shows any evidence for magnetic order above 2 K. Magnetization measurements suggest that Pr ions assume a nonmagnetic ?1 singlet or non-Kramers ?3 doublet ground state. A broad peak, which is identified as a Schottky anomaly, is observed in the specific heat at low temperature. Low-lying excitations involving the 4 f electrons persist down to 2 K for both PrNi2Cd20 and PrPd2Cd20 and related features are also observed in the magnetization and electrical resistivity.

  7. Spectral structure of 245-445 keV electrons and positrons in positron-thorium scattering

    NASA Astrophysics Data System (ADS)

    Bargholtz, Chr.; Holmberg, L.; Johansson, K. E.; Liljequist, D.; Tegnér, P.-E.; Vojdani, D.

    1989-09-01

    Anomalies in low-energy positron scattering from thorium are searched for. The incident positrons were emitted from a 68Ga source with an end-point energy of 1.90 MeV. Coincidences between electrons and positrons in the energy range 245-445 keV were registered in a double beta spectrometer. The electron and positron energy spectra are best described in terms of Bhabha scattering with a small additional structure at an energy of about 320 keV for both the electrons and the positrons. The significance of this peak is estimated to be three standard deviations. The spectrometer was also used in a study of scattering of electrons emitted in the decay of 90Y, with an end-point energy of 2.28 MeV. The electron-electron coincidence spectrum in the energy range 245-445 keV is well described as resulting from Möller scattering alone.

  8. 2. SANDY RIVER BRIDGE AT TROUTDALE, SOUTH END, LOOKING 20 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. SANDY RIVER BRIDGE AT TROUTDALE, SOUTH END, LOOKING 20 DEGREES NORTH. - Historic Columbia River Highway, Sandy River Bridge at Troutdale, Historic Columbia River Highway spanning Sandy River, Troutdale, Multnomah County, OR

  9. 47 CFR 20.2 - Other applicable rule parts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... COMMON CARRIER SERVICES COMMERCIAL MOBILE SERVICES § 20.2 Other applicable...applicable to licensees in the commercial mobile radio services include the following...standards and procedures concerning the marketing and importation of radio frequency...

  10. 47 CFR 20.2 - Other applicable rule parts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... COMMON CARRIER SERVICES COMMERCIAL MOBILE SERVICES § 20.2 Other applicable...applicable to licensees in the commercial mobile radio services include the following...standards and procedures concerning the marketing and importation of radio frequency...

  11. Information management using Web 2.0 technology

    E-print Network

    Duffy, Juliet (Juliet Maria)

    2009-01-01

    Web 2.0, the ultimate platform for tacit based knowledge work has finally arrived. User driven, collaborative platform based tools including wikis, web mash-ups, discussion boards, linkage based search engines, and tagging ...

  12. 20. BUILDING I, BAYS 3, 2 AND 1, AND BUILDING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. BUILDING I, BAYS 3, 2 AND 1, AND BUILDING K, VIEW SOUTHEAST, NORTHWEST ELEVATIONS - Public Service Railway Company, Newton Avenue Car Shops, Bounded by Tenth, Mount Ephraim, Border & Newton Avenue, Camden, Camden County, NJ

  13. Security & Privacy Challenges in E-Learning 2.0

    Microsoft Academic Search

    Edgar Weippl; Martin Ebner

    2008-01-01

    E-Learning 2.0 uses Web 2.0 tools for e-learning. New services on the Internet can be swiftly integrated into existing applications; students can create MashUps, for instance, using a variety of services on the Internet. The main risk comes from the fact that students and teachers are not entirely aware that their institution does not control these services. The servers are

  14. RadCat 2.0 User Guide.

    SciTech Connect

    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

  15. Web 2.0: blind to an accessible new world

    Microsoft Academic Search

    Joshua M. Hailpern; Loretta Guarino Reid; Richard Boardman; Srinivas Annam

    2009-01-01

    With the advent of Web 2.0 technologies, websites have evolved from static pages to dynamic, interactive Web-based applications with the ability to replicate common desktop functionality. However, for blind and visually impaired individuals who rely upon screen readers, Web 2.0 applications force them to adapt to an inaccessible use model. Many technologies, including WAI- ARIA, AJAX, and improved screen reader

  16. Web 2.0 applications in top Chinese university libraries

    Microsoft Academic Search

    Zhiping Han; Yan Quan Liu

    2010-01-01

    Purpose – This paper aims to explore the status and construction pattern of Web 2.0 technologies employed in top Chinese university libraries, their functionalities and features. Design\\/methodology\\/approach – A combination of online survey and content analysis methodology is applied to a sample of 38 top Chinese university libraries' web sites. The Web 2.0 tools are categorized by generally accepted standards

  17. 1-to 10-keV x-ray backlighting of annular wire arrays on the Sandia Z-machine using bent-crystal imaging techniques.

    SciTech Connect

    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.

  18. Semantik der UML 2.0 Semantik der UML WS04/05 1 20. Juli 2004

    E-print Network

    Cengarle, María Victoria

    Semantik der UML 2.0 Semantik der UML WS04/05 1 20. Juli 2004 #12;What is UML The Unified Model lifecycle, and across different implementation technologies. Semantik der UML WS04/05 2 20. Juli 2004 #12, · communicate with stakeholders, · drive the implementation. Semantik der UML WS04/05 3 20. Juli 2004 #12

  19. SPHY v2.0: Spatial Processes in HYdrology

    NASA Astrophysics Data System (ADS)

    Terink, W.; Lutz, A. F.; Simons, G. W. H.; Immerzeel, W. W.; Droogers, P.

    2015-02-01

    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.

  20. DL_POLY_2.0: A general-purpose parallel molecular dynamics simulation package

    Microsoft Academic Search

    W. Smith; T. R. Forester

    1996-01-01

    DL_POLY_2.0 is a general-purpose parallel molecular dynamics simulation package developed at Daresbury Laboratory under the auspices of the Council for the Central Laboratory of the Research Councils. Written to support academic research, it has a wide range of applications and is designed to run on a wide range of computers: from single processor workstations to parallel supercomputers. Its structure, functionality,

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

    SciTech Connect

    Siekhaus, W. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Teslich, N. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Weber, P. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-10-23

    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 U??Ga??, (UC)??Ga?? and U??Cs?, (UC)??Cs??, respectively.

  2. 36 CFR 222.2 - Management of the range environment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...DEPARTMENT OF AGRICULTURE RANGE MANAGEMENT Grazing and Livestock Use on the National Forest...control where the land is available for grazing. Associated private and other public...affected permittees, landowners, and grazing advisory boards involved, as well...

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

    ERIC Educational Resources Information Center

    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…

  4. Collaborative Writing with Web 2.0 Technologies: Education Students' Perceptions

    ERIC Educational Resources Information Center

    Brodahl, Cornelia; Hadjerrouit, Said; Hansen, Nils Kristian

    2011-01-01

    Web 2.0 technologies are becoming popular in teaching and learning environments. Among them several online collaborative writing tools, like wikis and blogs, have been integrated into educational settings. Research has been carried out on a wide range of subjects related to wikis, while other, comparable tools like Google Docs and EtherPad remain…

  5. Dedicated STEM for 200 to 40 keV operation

    Microsoft Academic Search

    N. Dellby; N. J. Bacon; P. Hrncirik; M. F. Murfitt; G. S. Skone; Z. S. Szilagyi; O. L. Krivanek

    2011-01-01

    A dedicated STEM developed for operation at primary energies from 200 keV to 40 keV and lower is described. It has a new cold field emission gun (CFEG) that gives a normalized brightness of 3 × 108 A\\/(m2 sr V), and excellent short-term and long-term stability. It includes two gun lenses (one electrostatic and one electromagnetic), a fast electrostatic beam

  6. The Lagrangian analysis tool LAGRANTO - version 2.0

    NASA Astrophysics Data System (ADS)

    Sprenger, M.; Wernli, H.

    2015-02-01

    Lagrangian trajectories are widely used in the atmospheric sciences, for instance to identify flow structures in extratropical cyclones (e.g., warm conveyor belts) and long-range transport pathways of moisture and trace substances. Here a new version of the Lagrangian analysis tool LAGRANTO (Wernli and Davies, 1997) is introduced, which offers considerably enhanced functionalities: (i) trajectory starting positions can be described easily based on different geometrical and/or meteorological conditions; e.g., equidistantly spaced within a prescribed region and on a stack of pressure (or isentropic) levels; (ii) a versatile selection of trajectories is offered based on single or combined criteria; these criteria are passed to LAGRANTO with a simple command language (e.g., "GT:PV:2" readily translates into a selection of all trajectories with potential vorticity (PV) greater than 2 PVU); and (iii) full versions are available for global ECMWF and regional COSMO data; core functionality is also provided for the regional WRF and UM models, and for the global 20th Century Reanalysis data set. The intuitive application of LAGRANTO is first presented for the identification of a warm conveyor belt in the North Atlantic. A further case study then shows how LAGRANTO is used to quasi-operationally diagnose stratosphere-troposphere exchange events over Europe. Whereas these example rely on the ECMWF version, the COSMO version and input fields with 7 km horizontal resolution are needed to adequately resolve the rather complex flow structure associated with orographic blocking due to the Alps. Finally, an example of backward trajectories presents the tool's application in source-receptor analysis studies. The new distribution of LAGRANTO is publicly available and includes simple tools, e.g., to visualize and merge trajectories. Furthermore, a detailed user guide exists, which describes all LAGRANTO capabilities.

  7. High range gamma radiation meter

    SciTech Connect

    Baird, W.; Bjarke, D.; Eisen, Y.

    1986-02-01

    A low power meter has been constructed and tested to measure gamma fields from .1 R/h to 1500 R/h over the energy range of 60 keV to 1.2 MeV. The portable, battery-powered meter consists of a local display unit and remote probe. The display unit indicates gamma intensities via a 4-1/2 digit liquid crystal display (LCD) and a 50-segment bargraph LCD.

  8. High range gamma radiation meter

    SciTech Connect

    Baird, W.; Bjarke, G.O.; Eisen, Y.

    1985-01-01

    A low power meter has been constructed and tested to measure gamma fields from .1 R/hr to 1500 R/hr over the energy range of 60 keV to 1.2 MeV. The portable, battery-powered meter consists of a local display unit and remote probe. The display unit indicates gamma intensities via a 4-1/2 digit liquid crystal display (LCD) and a 50-segment bargraph LCD.

  9. Geologic Carbon Sequestration and Biosequestration (Carbon Cycle 2.0)

    ScienceCinema

    DePaolo, Don [Director, LBNL Earth Sciences Division

    2011-06-08

    Don DePaolo, Director of LBNL's Earth Sciences Division, speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 3, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

  10. Carbon Cycle 2.0: Paul Alivisatos: Introduction

    ScienceCinema

    Paul Alivisatos

    2010-09-01

    Berkeley Lab Director Paul Alivisatos speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 1, 2010. Humanity emits more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences.Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

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

    SciTech Connect

    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%.

  12. Incorporating Web 2.0 Technologies from an Organizational Perspective

    NASA Astrophysics Data System (ADS)

    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 SIMILE project at MIT (Massachusetts Institute of Technology) for displaying time-based events in a clean, horizontal timeline display. Numerous standards, applications, and 3rd party integration services are also available for use in today's Web 2.0 environment. In addition to a cohesive online platform, the following tools can improve networking, information sharing, and increased scientific and educational collaboration: ? Facebook (Fan pages, social networking, etc) ? Twitter/Twitterfeed (Automatic updates in 3 steps) ? Mobify.me (Mobile web) ? Wimba, Adobe Connect, etc (real time conferencing) Increasingly, the scientific community is being asked to share data and information within and outside disciplines, with K-12 students, and with members of the public and policy-makers. Web 2.0 technologies can easily be set up and utilized to share data and other information to specific audiences in real time, and their simplicity ensures their increasing use by the science community in years to come.

  13. Photodissociation dynamics of CH2I2 molecules in the ultraviolet range studied by ion imaging

    E-print Network

    Liu, Shilin

    in the range of 265­304 nm and by Kroger et al.12 at 266 nm, showed that t range of 277­305 nm by an ion imaging spectrometer operated under optimal conditions for velocity/2) fragments with the same laser as that to dissociate the parent molecules. The speed and angular

  14. On-line range prediction system, part 2

    NASA Technical Reports Server (NTRS)

    Levan, Nhan

    1988-01-01

    The on-line range prediction system is designed for providing a prediction of the target range in the case of a laser data dropout. It consists of real time implementation of a Kalman filter on an IBM PC/AT equipped with necessary hardware. The system was set up and tested at Crows Landing in the Fall of 1987. The improvements made on the on-line range prediction system during 1988 are examined. Solutions are proposed and discussed to the several problems encountered during system tests. Then, the improvements made on the filter software are explained, namely, accounting for the time lag and providing data continously. Finally, the ideas are mentioned that can be considered in the future.

  15. Exploring technology impacts of Healthcare 2.0 initiatives.

    PubMed

    Randeree, Ebrahim

    2009-04-01

    As Internet access proliferates and technology becomes more accessible, the number of people online has been increasing. Web 2.0 and the social computing phenomena (such as Facebook, Friendster, Flickr, YouTube, Blogger, and MySpace) are creating a new reality on the Web: Users are changing from consumers of Web-available information and resources to generators of information and content. Moving beyond telehealth and Web sites, the push toward Personal Health Records has emerged as a new option for patients to take control of their medical data and to become active participants in the push toward widespread digitized healthcare. There is minimal research on the impact of Web 2.0 in healthcare. This paper reviews the changing patient-physician relationship in the Healthcare 2.0 environment, explores the technological challenges, and highlights areas for research. PMID:19382863

  16. mHealth 2.0: Experiences, Possibilities, and Perspectives

    PubMed Central

    Diamantidis, Clarissa

    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

  17. Verification and validation of DEPOSITION 2.0

    SciTech Connect

    Eadie, W.J.

    1994-10-01

    The purpose of this document is to verify and validate the usage of the computer program, DEPOSITION 2.0 for use in assessing line loss in CAM and fixed head lines throughout certain Hanford Site facilities. The scope of use is limited to this function. DEPOSITION 2.0 is the second version of this code to be used on the Hanford Site, the program now incorporates additional user-friendly features beyond those which were available in an earlier version, DEPOSITION 1.03.

  18. Short-range demonstrations of monocular passive ranging using O2 (X3?g- ? b1?g+) absorption spectra.

    PubMed

    Hawks, Michael R; Vincent, R Anthony; Martin, Jacob; Perram, Glen P

    2013-05-01

    The depth of absorption bands in observed spectra of distant, bright sources can be used to estimate range to the source. Experimental results are presented based on observations of the O2 X(v" = 0) ? b(v' = 0) absorption band centered around 762 nm and the O2 X(v" = 0) ? b(v' = 1) band around 689 nm. Range is estimated by comparing observed values of band-average absorption against predicted curves derived from either historical data or model predictions. Accuracy of better than 0.5% was verified in short-range (up to 3 km), static experiments using a high-resolution (1 cm(-1)) spectroradiometer. This method was also tested against the exhaust plume of a Falcon 9 rocket launched from Cape Canaveral, Florida. The rocket was launched from an initial range of 13 km and tracked for 90 s after ignition. Range error was below 2% for the first 30 s and consistent with predicted error throughout the track. PMID:23643040

  19. The C3H2 2(20)-2(11) transition - Absorption in cold dark clouds

    NASA Technical Reports Server (NTRS)

    Matthews, H. E.; Avery, L. W.; Madden, S. C.; Irvine, W. M.

    1986-01-01

    The first observations of the 2(20)-2(11) transition of cyclopropenylidene (C3H2) at 21.6 GHz are described. The most significant finding is that the 2(20)-2(11) transition line is always seen in absorption, in contrast to the 18.3-GHz 1(10)-1(01) resonance line of the ortho species which always appears in emission in cold dust clouds. Thus the former must have an excitation temperature less than the brightness temperature of the universal microwave background and becomes only the second molecule to exhibit such 'refrigeration' below this temperature in cold, dark dust clouds.

  20. Case 2:05-cr-00180-LRS Document 150 Filed 03/20/2006 Case 2:05-cr-00180-LRS Document 150 Filed 03/20/2006

    E-print Network

    Gollin, George

    Case 2:05-cr-00180-LRS Document 150 Filed 03/20/2006 #12;Case 2:05-cr-00180-LRS Document 150 Filed 03/20/2006 #12;Case 2:05-cr-00180-LRS Document 150 Filed 03/20/2006 #12;Case 2:05-cr-00180-LRS Document 150 Filed 03/20/2006 #12;Case 2:05-cr-00180-LRS Document 150 Filed 03/20/2006 #12;Case 2:05-cr

  1. HELIOSPHERIC NEUTRAL ATOM SPECTRA BETWEEN 0.01 AND 6 keV FROM IBEX

    SciTech Connect

    Fuselier, S. A.; Ghielmetti, A. G.; Petrinec, S. M.; Trattner, K. J., E-mail: sfuselier@swri.edu, E-mail: fallegrini@swri.edu [Lockheed Martin Advanced Technology Center, Palo Alto, CA 94304 (United States); and others

    2012-07-20

    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{sup -1}.

  2. Einfhrung in Web 2.0-Dienste / Voss, Jakob. Workshop Leipzig : MPI, 2007-09-06 Web 2.0-Anwendungen

    E-print Network

    Einführung in Web 2.0-Dienste / Voss, Jakob. Workshop ­ Leipzig : MPI, 2007-09-06 Web 2.0-Anwendungen für Bibliothekare #12;Einführung in Web 2.0-Dienste / Voss, Jakob. Workshop ­ Leipzig : MPI, 2007. Workshop ­ Leipzig : MPI, 2007-09-06 Web 2.0-Geschichte 1962: Doug Englebart: Augmenting Human Intellect

  3. Developing the World Health Organization Disability Assessment Schedule 2.0

    PubMed Central

    Chatterji, Somnath; Kostanjsek, Nenad; Rehm, Jürgen; Kennedy, Cille; Epping-Jordan, Joanne; Saxena, Shekhar; von Korff, Michael; Pull, Charles

    2010-01-01

    Abstract Objective To describe the development of the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) for measuring functioning and disability in accordance with the International Classification of Functioning, Disability and Health. WHODAS 2.0 is a standard metric for ensuring scientific comparability across different populations. Methods A series of studies was carried out globally. Over 65?000 respondents drawn from the general population and from specific patient populations were interviewed by trained interviewers who applied the WHODAS 2.0 (with 36 items in its full version and 12 items in a shortened version). Findings The WHODAS 2.0 was found to have high internal consistency (Cronbach's alpha, ?: 0.86), a stable factor structure; high test-retest reliability (intraclass correlation coefficient:?0.98); good concurrent validity in patient classification when compared with other recognized disability measurement instruments; conformity to Rasch scaling properties across populations, and good responsiveness (i.e. sensitivity to change). Effect sizes ranged from 0.44 to 1.38 for different health interventions targeting various health conditions. Conclusion The WHODAS 2.0 meets the need for a robust instrument that can be easily administered to measure the impact of health conditions, monitor the effectiveness of interventions and estimate the burden of both mental and physical disorders across different populations. PMID:21076562

  4. Updated 2/20/14 Minor in Education

    E-print Network

    Massachusetts at Amherst, University of

    Updated 2/20/14 Minor in Education University of Massachusetts Amherst The Minor in Education is a way for students interested in education to explore various theoretical aspects of education in the area of education and be well-prepared to enter a licensure program, graduate program, or career

  5. Reality 2.0: When Loss Is Lost

    Microsoft Academic Search

    Stephen Hartman

    2011-01-01

    Cyberspace is provoking a dramatic shift in our cultural understanding of reality. A transition is taking place, from a reality marked by loss and limit to one experienced through infinite access. This paper begins to map Reality 2.0 with the conviction that we need to revisit traditional psychoanalytic concepts such as loss and fantasy within the framework of this new

  6. DESIGNING HUMAN 2.0 (TRANSHUMAN) – REGENERATIVE EXISTENCE

    Microsoft Academic Search

    Natasha Vita-More

    2008-01-01

    This paper explores regenerative existence for Human 2.0 – the transhuman. In building this focus, the author addresses the use of emerging technologies as propitious in designing the amended, extended, and suspended human body. Here, a first focus covers emerging biotechnologies for regenerative existence, which play a large role in extreme life extension. A second focus covers the digital technologies

  7. Social recommender systems for web 2.0 folksonomies

    Microsoft Academic Search

    Stefan Siersdorfer; Sergej Sizov

    2009-01-01

    The rapidly increasing popularity of Web 2.0 knowledge and content sharing systems and growing amount of shared data make discovering relevant content and flnding contacts a dif- flcult enterprize. Typically, folksonomies provide a rich set of structures and social relationships that can be mined for a variety of recommendation purposes. In this paper we propose a formal model to characterize

  8. Libsafe 2.0: Detection of Format String Vulnerability Exploits

    Microsoft Academic Search

    Timothy Tsai; Navjot Singh

    2001-01-01

    This white paper describes a significant new feature of libsafe version 2.0: the ability to detect and handle format string vulnerability exploits. Such exploits have recently garnered attention in security advisories, discussion lists, web sites devoted to security, and even conventional media such as television and newspapers. Examples of vulnerable software include wu-ftpd (a common FTP daemon) and bind (A

  9. MULTIPLE PROJECTS SYSTEM (MPS) VERSION 2.0 - USER'S MANUAL

    EPA Science Inventory

    The document is a user's manual for Multiple Projections System (MPS) Version 2.0, based on the 3% reasonable further progress (RFP) tracking system that was developed in FY92/FY93. he 3% RFP tracking system is a Windows application, and enhancements to convert the 3% RFP trackin...

  10. MULTIPLE PROJECTIONS SYSTEM (MPS): USER'S MANUAL VERSION 2.0

    EPA Science Inventory

    The document is a user's manual for Multiple Projections System (MPS) Version 2.0, based on the 3% reasonable further progress (RFP) tracking system that was developed in FY92/FY93. The 3% RFP tracking system is a Windows application, and enhancements to convert the 3% RFP track...

  11. Carbon Cycle 2.0: Nitash Balsara: Energy Storage

    ScienceCinema

    Nitash Balsara

    2010-09-01

    Feb. 4, 2010: Humanity emits more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future.

  12. 2.0 at AASL 2009 National Conference in Charlotte

    ERIC Educational Resources Information Center

    Valenza, Joyce Kasman

    2009-01-01

    School library media specialists are information and communication specialists who lead and model these roles in schools and at their major professional events making use of the relevant new Web 2.0 tools available to them to network, collaborate, and share. Using these tools effectively helps them become leaders in their buildings and districts.…

  13. Animer le web 2.0 Community manager

    E-print Network

    Paris-Sud XI, Université de

    on-line des différentes communautés (professionnelles et/ou autres) de la société. Pour N de l'information, les nouveaux médias. Du jeu au marketing Au début, il y avait le jeu. Tout est là communication, relation clientèle et marketing. « Le web 2.0 a introduit de nombreuses mutations dans la

  14. Web 2.0 and Emerging Technologies in Online Learning

    ERIC Educational Resources Information Center

    Diaz, Veronica

    2010-01-01

    As online learning continues to grow, so do the free or nearly free Web 2.0 and emerging online learning technologies available to faculty and students. This chapter explores the implementation process and corresponding considerations of adapting such tools for teaching and learning. Issues addressed include copyright, intellectual property,…

  15. ECONOMIC GROWTH ANALYSIS SYSTEM: REFERENCE MANUAL VERSION 2.0

    EPA Science Inventory

    The two-volume report describes the development of and provides information needed to operate, the Economic Growth Analysis System (E-GAS) Version 2.0 model. The model will be used to project emissions inventories of volatile organic compounds (VOCs), oxides of nitrogen (NOx), a...

  16. ECONOMIC GROWTH ANALYSIS SYSTEM: REFERENCE MANUAL - VERSION 2.0

    EPA Science Inventory

    The two-volume report describes the development of and provides information needed to operate, the Economic Growth Analysis System (E-GAS) Version 2.0 model. he model will be used to project emissions inventories of volatile organic compounds (VOCs), oxides of nitrogen (NOx), and...

  17. ECONOMIC GROWTH ANALYSIS SYSTEM: USER'S GUIDE - VERSION 2.0

    EPA Science Inventory

    The two-volume report describes the development of and provides information needed to operate, the Economic Growth Analysis System (E-GAS) Version 2.0 model. he model will be used to project emissions inventories of volatile organic compounds (VOCs), oxides of nitrogen (NOx), and...

  18. ECONOMIC GROWTH ANALYSIS SYSTEM: USER'S GUIDE VERSION 2.0

    EPA Science Inventory

    The two-volume report describes the development of and provides information needed to operate, the Economic Growth Analysis System (E-GAS) Version 2.0 model. The model will be used to project emissions inventories of volatile organic compounds (VOCs), oxides of nitrogen (NOx), a...

  19. Carbon Cycle 2.0: Jay Keasling: Biofuels

    ScienceCinema

    Jay Keasling

    2010-09-01

    Feb. 4, 2010: Humanity emits more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future.

  20. Special Issue Synthetic Cell Biology Cell Biology 2.0

    E-print Network

    Lim, Wendell

    Special Issue ­ Synthetic Cell Biology Cell Biology 2.0 Wendell A. Lim1 , Rebecca Alvania3-2200, USA 3 Editor, Trends in Cell Biology `Verum esse ipsum factum', the true is in the made ­ Giambattista Vico Synthetic Cell Biology sounds intriguing, but the name begs the question ­ why should we try

  1. Different Spaces: Staff Development for Web 2.0

    ERIC Educational Resources Information Center

    Samarawickrema, Gayani; Benson, Robyn; Brack, Charlotte

    2010-01-01

    This paper reports on a collaborative staff development activity run across two Australian universities, for academic staff integrating Web 2.0 technologies into their teaching. It describes a three-week long virtual workshop on teaching with wikis, where participants in two groups developed a group project as students and then assessed the work…

  2. AHA! Version 2.0 More Adaptation Flexibility for Authors

    E-print Network

    De Bra, Paul

    AHA! Version 2.0 More Adaptation Flexibility for Authors Paul De Bra* , Ad Aerts, David Smits we will refer to as AHA! Version 1.0 in this paper, and which is described e.g. in (De Bra et al., 2000) and (De Bra & Ruiter, 2001). AHA! 1.0 is based on a simple architecture for an adaptive Web

  3. AHA! Version 2.0: More Adaptation Flexibility for Authors.

    ERIC Educational Resources Information Center

    De Bra, Paul; Aerts, Ad; Smits, David; Stash, Natalia

    AHA! is a simple Web-based adaptive hypermedia system. Because of this simplicity it has been studied and experimented with in several research groups. This paper identifies shortcomings in AHA! and presents AHA! version 2.0 which tries to overcome the known problems with AHA! while maintaining its biggest asset: simplicity. The paper illustrates…

  4. Codegenerierung für Assoziationen in MOF 2.0

    Microsoft Academic Search

    Carsten Amelunxen; Andy Schürr; Lutz Bichler

    2004-01-01

    Die Spezifikation von MOF 2.0 enth ¨ alt neue Konstrukte zum Ausdr¨ ucken von Beziehungen zwischen Assoziationen. Damit diese Konstrukte in modellgetriebenen Entwicklungsprozessen sinnvoll eingesetzt werden k ¨ onnen, werden Abbildungen auf objektorientierte Programmiersprachen ben ¨ otigt. Im Rahmen dieses Papiers stellen wir M¨ oglichkeiten vor, die neuen Konstrukte auf Java-Code abzubilden. Unsere Vor- schl¨ age basieren auf dem Java

  5. LOVELY PAIRS FOR INDEPENDENCE RELATIONS VERSION 2.0

    E-print Network

    Fornasiero, Antongiulio

    LOVELY PAIRS FOR INDEPENDENCE RELATIONS VERSION 2.0 ANTONGIULIO FORNASIERO Abstract. In the literature there are two different notions of lovely pairs of a theory T, according to whether T is simple or geometric. We introduce a notion of lovely pairs for an independence relation, which generalizes both

  6. Changing Academic Teaching with Web 2.0 Technologies

    ERIC Educational Resources Information Center

    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…

  7. Conceptualising Teachers' Professional Learning with Web 2.0

    ERIC Educational Resources Information Center

    Burden, Kevin John

    2010-01-01

    Purpose: This paper seeks to identify and develop an exploratory framework for conceptualising how teachers might use the affordances of Web 2.0 technologies to support their own professional learning. Design/methodology/approach: The paper draws on a large corpus of literature and recent research evidence to identify the principal elements and…

  8. Integrating Web 2.0 across the Curriculum

    ERIC Educational Resources Information Center

    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…

  9. Web 2.0 Tools for Supporting Teaching

    ERIC Educational Resources Information Center

    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…

  10. RASCAL2.0A. Radiological Dose Assessment System

    Microsoft Academic Search

    A. L. Sjoreen; G. F. Athey; J. V. Ramsdell; T. J. McKeena

    1993-01-01

    RASCAL2.0A (Radiologic Assessment System for Consequence Analysis) has been developed for use during response to radiological emergencies. The model is designed to provide a rough comparison to EPA Protective Action Guidance and thresholds for acute health effects. RASCAL will be used by the NRC personnel who report to the site of a nuclear accident to conduct an independent evaluation of

  11. Teaching Talented Writers with Web 2.0 Tools

    ERIC Educational Resources Information Center

    Olthouse, Jill M.; Miller, Myriah Tasker

    2012-01-01

    This article is a review of 12 online writing resources and contains suggestions about how such resources might be used in a differentiated classroom with talented writers. Youth with writing talent are defined by distinguishing characteristics and the authors discuss how those characteristics can be supported and enhanced using Web 2.0 tools.…

  12. Outcome-Driven Experiential Learning with Web 2.0

    ERIC Educational Resources Information Center

    Huang, C. Derrick; Behara, Ravi S.

    2007-01-01

    Experiential learning, an effective pedagogical method in MIS and other business courses, has been limited by instructional formats and teaching resources. But with the advent of Web 2.0 and its rich set of social networking and mass authoring tools, a shift in learning structure in content, process, and outcome is emerging. In this paper, we…

  13. Librarians 2.0: Sowing Padi in (the) SEA

    ERIC Educational Resources Information Center

    Chew, Ivan

    2009-01-01

    Purpose: The purpose of this paper is to present an exploratory survey as part of a presentation for the Bridging Worlds 2008 conference. It seeks to understand how library institutions in the South East Asia (SEA) region have implemented Web 2.0 technologies--blogs, RSS feeds, wikis, or the use of services like Flickr, YouTube, de.lici.ous.…

  14. RefWorks 2.0 (revised Aug. 2011)

    E-print Network

    University of Technology, Sydney

    © RefWorks-COS, A Business Unit of ProQuest LLC Introduction The workbook is designed to guide users Workbook Page 3 © RefWorks-COS, A Business Unit of ProQuest LLC Task 1: Advanced Searching Task 2: Using reference. #12;RefWorks 2.0 Advanced User Workbook Page 4 © RefWorks-COS, A Business Unit of ProQuest LLC

  15. High energy resolution measurement of the /sup 238/U neutron capture yield in the energy region between 1 and 100 keV

    SciTech Connect

    Machlin, R.L.; Perez, R.B.; de Saussure, G.; Ingle, R.W.

    1988-01-01

    A measurement of the /sup 238/U neutron capture yield was performed at the 150 meter flight-path of the ORELA facility on two /sup 238/U samples (0.01224 and 0.0031 atomsbarn). The capture yeild data were normalized by Moxon's small resonance method. The energy resolution achieved in this measurement frequently resulted in doublet and triplet splittings of what appeared to be single resonance in previous measurements. This resolution should allow extension of the resolved resonance energy region in /sup 238/U from the present 4-keV limit up to 15 or 20 keV incident neutron energy. Some 200 small resonances of the (/sup 238/U /plus/ n) compound nucleus have been observed which had not been detected in transmission measurement, in the energy range from 250 eV to 10 keV.

  16. Physics news Update 783 file:///C:/Documents%20and%20Settings/Gabrielse/Local%20Settings/... 1 of 3 8/15/2006 2:34 PM

    E-print Network

    Gabrielse, Gerald

    Physics news Update 783 file:///C:/Documents%20and%20Settings/Gabrielse/Local%20Settings/... 1 of 3 8/15/2006 2:34 PM AIP 75th Anniversary - Home search advanced search h i Physics News Update Subscribe to Physics News Update Physics News Graphics Physical Review Focus Physics News Links Archives

  17. Sputtering yields and Specific energy losses of Ar Ions with energies from 5 TO 30 KeV AT SiO2

    Microsoft Academic Search

    H. Bach; I. Kitzman; H. Schröder

    1974-01-01

    Sputtering yields are determined from interference micrographs of the etched pits developing during ablation of discharged silica surfaces by a homogeneous Ar ion beam at normal incidence. The maximum of the sputtering yield was found to be 1.8 atoms per incident ion at about 20 keV.The bombardment of thin silica layers on a glass substrate results in photoemission of sputtered

  18. Spatial resolution of synchrotron x-ray microtomography in high energy range: Effect of x-ray energy and sample-to-detector distance

    SciTech Connect

    Seo, D.; Tomizato, F.; Toda, H.; Kobayashi, M. [Department of Mechanical Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441-8580 (Japan); Uesugi, K.; Takeuchi, A.; Suzuki, Y. [Japan Synchrotron Radiation Research Institute, Mikazuki, Sayo, Hyogo 679-5198 (Japan)

    2012-12-24

    Spatial resolution of three-dimensional images obtained by synchrotron X-ray microtomography technique is evaluated using cyclic bar patterns machined on a steel wire. Influences of X-ray energy and the sample-to-detector distance on spatial resolution were investigated. High X-ray energies of 33-78 keV are applied due to the high X-ray absorption of transition metals. Best spatial resolution of about 1.2 {mu}m pitch was observed at the sample-to-detector distance range of 20-110 mm and at the energy range of 68-78 keV. Several factors such as X-ray scattering and diffraction phenomena affecting the degradation of spatial resolution are also discussed.

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

    ERIC Educational Resources Information Center

    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…

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

    ERIC Educational Resources Information Center

    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.…

  1. The ^14N(p,?_o)^15O Reaction below 140 keV

    NASA Astrophysics Data System (ADS)

    Nelson, S. O.; Kelley, J. H.; Canon, R. S.; Schreiber, E. C.; Saburov, K.; Wulf, E. A.; Weller, H. R.; Prior, R. M.; Spraker, M.; Tilley, D. R.

    1999-10-01

    The capture reaction ^14N(p,?)^15O is the limiting reaction in the CNO cycle. Very little data exists at beam energies below the Ep = 278 keV resonance for this reaction(U. Schroder et al., Nucl. Phys. A467) 240 (1987).^,(W. Lamb and R. Hester, Phys. Rev. 108) 1304 (1957).. Using a 140 keV polarized proton beam and a thick frozen trideuterio ammonia (ND_3) target, we have measured the astrophysical S-factor for the reaction relative to the S-factor for the D(p,?)^3He reaction in this energy region. The outgoing gamma rays were detected in a 140% HPGe detector. The D(p,?)^3He reaction also provided a convenient reference for the energy calibration of this detector. Preliminary analysis suggests that the S-factor for the ^14N(p,?_o)^15O reaction in this energy range is significantly larger than previously assumed^2.

  2. Ion beam-induced anisotropic plastic deformation at 300 keV

    NASA Astrophysics Data System (ADS)

    van Dillen, T.; Polman, A.; van Kats, C. M.; van Blaaderen, A.

    2003-11-01

    Contrary to earlier predictions, ion irradiation at energies as low as 300 keV causes dramatic anisotropic plastic deformation of silica glass. Spherical colloidal silica particles with diameters of 125, 305, and 1030 nm were irradiated with Xe ions at energies in the range 0.3-4.0 MeV at temperatures between 85 and 380 K. Irradiation-induced anisotropic plastic deformation changes the colloid shape from spherical into oblate ellipsoidal at a rate that strongly increases with ion energy. At a fixed fluence, the transverse diameter increases with electronic energy loss. Even at an energy as low as 300 keV large particle anisotropy was found (size aspect ratio of 1.43 at 1×1015 cm-2). The transverse plastic strain gradually decreases with increasing irradiation temperature: it decreases by a factor 4.5 between 85 and 380 K. The data are in agreement with a viscoelastic thermal spike model for anisotropic deformation.

  3. Effect of 200 keV Ar+ implantation on optical & electrical properties of polyethyleneterepthalate (PET)

    NASA Astrophysics Data System (ADS)

    Kumar, Rajiv; Goyal, Meetika; Sharma, Ambika; Aggarwal, Sanjeev; Sharma, Annu; Kanjilal, D.

    2015-05-01

    In the present paper we have discussed the effect of 200 keV Ar+ ions on the electrical and optical properties of PET samples. PET samples were implanted with 200 keV Ar+ ions to various doses ranging from 1×1015 to 1×1017 Ar+ cm2. The changes in the electrical and optical properties of pristine and implanted PET specimens have been studied by using Keithley electrometer and UV-Visible absorption spectroscopy. The electrical conductivity has found to be increased with increasing ion dose. The optical studies have revealed the drastic alterations in optical band gap from 3.63 eV to 1.48 eV and also increase in number of carbon atoms per cluster from 215 to 537. Further, the change in the electrical conductivity and optical band gap has also been correlated with the formation of conductive islands in the implanted layers of PET.

  4. From Zero to Web 2.0: Part 2

    ERIC Educational Resources Information Center

    Woodard, Amber

    2009-01-01

    During the summer semester, the Vise Library at Cumberland University (CU) began working on its "digital makeover." It has six goals: (1) Create a more user-friendly and dynamic website; (2) Activate and maintain accounts on social networking sites such as Facebook, MySpace, and Twitter; (3) Produce a library blog that allows students, staff, and…

  5. Short-Range Magnetic Correlations and Parimagnetism in RCo2

    SciTech Connect

    Bartolome, F. [CSIC - Universidad de Zaragoza; Bonilla, C. M. [CSIC - Universidad de Zaragoza; Herrero-Albillos, J. [CSIC - Universidad de Zaragoza; Calvo-Almazan, I. [CSIC - Universidad de Zaragoza; Castan, C. [CSIC - Universidad de Zaragoza; Weschke, E. [Helmholtz-Zentrum Berlin fur Materialien und Energie GmbH; Schmitz, D. [Helmholtz-Zentrum Berlin fur Materialien und Energie GmbH; Paudyal, Durga [Ames Laboratory; Mudryk, Yaroslav [Ames Laboratory; Pecharsky, Vitalij [Ames Laboratory; Gschneidner Jr., Karl A. [Ames Laboratory; Stunault, A. [Institut Laue-Langevin; Garcia, L. M. [CSIC - Universidad de Zaragoza

    2013-12-02

    X-ray circular magnetic dichroism, polarized neutron diffraction, ac susceptibility, and Seebeck effect have been measured for several members of the RCo2 series (R=Ho, Tm, Er) as a function of temperature and applied magnetic field. The experimental results show robust parimagnetism (a general behaviour along the RCo2 series with R being a heavy rare earth ion) and two reversal temperatures in some systems, which is an unexpected result. Polarised neutron diffraction show differences between results obtained on single crystals or polycrystalline ingots. We propose an interpretation of parimagnetic RCo2 as a Griffiths phase of the high temperature, magnetically ordered, amorphous RCo2 phase. Copyright EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2013

  6. Ground Support for the Space-Based Range Flight Demonstration 2

    NASA Technical Reports Server (NTRS)

    Burkes, Darryl A.

    2007-01-01

    The primary objective of the NASA Space-Based Range Demonstration and Certification program was to develop and demonstrate space-based range capabilities. The Flight Demonstration 2 flights at NASA Dryden Flight Research Center were conducted to support Range Safety (commanding and position reporting) and high-rate (5 Mbps) Range User (video and data) requirements. Required ground support infrastructure included a flight termination system computer, the ground-data distribution network to send range safety commands and receive range safety and range user telemetry data and video, and the ground processing systems at the Dryden Mission Control Center to process range safety and range user telemetry data and video.

  7. Barcelona, Spain, November 17 -20, 2013 MOBILITY 2.0: CO-OPERATIVE ITS SYSTEMS FOR

    E-print Network

    Boyer, Edmond

    mobility: `range anxiety' related to the limited FEV range, scarcity of parking spaces with public can be achievable: Limited FEV range, which may lead to a `range anxiety' of drivers in the absence the range autonomy accurately but also provide a multi- modal commute trip recommendation to the FEV user

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

    NASA Technical Reports Server (NTRS)

    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.

  9. A Study of Web 2.0 Website Usage Behavior Using TAM 2

    Microsoft Academic Search

    Mei-Ying Wu; Han-Ping Chou; Yung-Chien Weng; Yen-Han Huang

    2008-01-01

    Web 2.0 is a new Internet platform that allows users to build personalized content through participation and sharing. The technologies used and business opportunities brought by this new platform have impacted many conventional Websites. This paper aims to explore the relationships among constructs in Technology Acceptance Model 2 (TAM 2) and survey the general userspsila acceptance of Web 2.0 Websites.

  10. Communication: A simple full range analytical potential for H2b(3)?u (+), H-He (2)?(+), and He2 (1)?g (.).

    PubMed

    Warnecke, Sascha; Tang, K T; Toennies, J Peter

    2015-04-01

    The Tang-Toennies potential for the weakly interacting systems H2b(3)?u (+), H-He (2)?(+), and He2 (1)?g (+) is extended down to the united atom limit of vanishing internuclear distance. A simple analytic expression connects the united atom limiting potential with the Tang-Toennies potential in the well region. The new potential model is compared with the most recent ab initio calculations for all three systems. The agreement is better than 20% (H2 and He2) or comparable with the differences in the available ab initio calculations (H-He) over six orders of magnitude corresponding to the entire range of internuclear distances. PMID:25854220

  11. PSEUDOMARKER 2.0: efficient computation of likelihoods using NOMAD

    PubMed Central

    2014-01-01

    Background PSEUDOMARKER is a software package that performs joint linkage and linkage disequilibrium analysis between a marker and a putative disease locus. A key feature of PSEUDOMARKER is that it can combine case-controls and pedigrees of varying structure into a single unified analysis. Thus it maximizes the full likelihood of the data over marker allele frequencies or conditional allele frequencies on disease and recombination fraction. Results The new version 2.0 uses the software package NOMAD to maximize likelihoods, resulting in generally comparable or better optima with many fewer evaluations of the likelihood functions. Conclusions After being modified substantially to use modern optimization methods, PSEUDOMARKER version 2.0 is more robust and substantially faster than version 1.0. NOMAD may be useful in other bioinformatics problems where complex likelihood functions are optimized. PMID:24533837

  12. Neutron scattering and scaling behavior in URu2Zn20 and YbFe2Zn20 C. H. Wang1,2

    E-print Network

    Lawrence, Jon

    Neutron scattering and scaling behavior in URu2Zn20 and YbFe2Zn20 C. H. Wang1,2 , A. D susceptibility (E), measured by inelastic neutron scattering measurements, shows a broad peak centered at Emax of the neutron scattering spectra (E) of polycrystalline samples[5]. The theoretical calculations[1­4] show

  13. Effect of the electropositive elements A = Sc, La, and Ce on the microscopic dynamics of AV2Al20.

    PubMed

    Koza, Michael Marek; Leithe-Jasper, Andreas; Sischka, Erik; Schnelle, Walter; Borrmann, Horst; Mutka, Hannu; Grin, Yuri

    2014-12-28

    We report on the inelastic response of AV2Al20 (with A = Sc, La and Ce) probed by high-resolution inelastic neutron scattering experiments. Intense signals associated with the dynamics of Sc, La and Ce are identified in the low-energy range at 6-14 meV in ScV2Al20 and at 8-16 meV in LaV2Al20 and CeV2Al20. Their response to temperature changes between 2 and 300 K reveals a very weak softening of the modes upon heating in LaV2Al20 and CeV2Al20 and a distinguished blue shift by about 2 meV in ScV2Al20. By means of density functional theory (DFT) and lattice dynamics calculations (LDC) we show that the unusual anharmonicity of the Sc-dominated modes is due to the local potential of Sc featured by a strong quartic term. The vibrational dynamics of ScV2Al20 as well as of LaV2Al20 and CeV2Al20 is reproduced by a set of eigenmodes. To screen the validity of the DFT and LDC results they are confronted with data from X-ray diffraction measurements. The effect of the strong phonon renormalization in ScV2Al20 on thermodynamic observables is computed on grounds of the LDC derived inelastic response. To set the data in a general context of AV2Al20 compounds and their physical properties we report in addition computer and experimental results of the binary V2Al20 compound. PMID:25388502

  14. Web 2.0: easy tools for busy clinicians.

    PubMed

    Phillippi, Julia C; Buxton, Margaret

    2010-01-01

    Internet content has become interactive; new tools can help clinicians market their practice and provide evidence-based care. Many of these tools are free or low cost and are easily mastered using simple video tutorials found on the Internet. This article highlights the uses of e-mail, social networking, smartphones, RSS feeds, social bookmarking, and collaborative Web 2.0 tools in clinical practice. PMID:20732669

  15. Some User's Insights Into ADIFOR 2.0D

    NASA Technical Reports Server (NTRS)

    Giesy, Daniel P.

    2002-01-01

    Some insights are given which were gained by one user through experience with the use of the ADIFOR 2.0D software for automatic differentiation of Fortran code. These insights are generally in the area of the user interface with the generated derivative code - particularly the actual form of the interface and the use of derivative objects, including "seed" matrices. Some remarks are given as to how to iterate application of ADIFOR in order to generate second derivative code.

  16. Code Splitting for Network Bound Web 2.0 Applications

    Microsoft Academic Search

    Benjamin Livshits; Chen Ding

    2007-01-01

    ModernWeb 2.0 applications such as Gmail, Live Maps, MySpace, Flickr and many others have become a common part of everyday life. These applications are network bound, meaning that their performance can and does vary a great deal based on network conditions. However, there has not been much systematic research on trying to optimize network usage of these applications to make

  17. Aspects of the D=6, (2,0) Tensor Multiplet

    E-print Network

    P. S. Howe

    2000-08-04

    Some aspects of the $D=6, (2,0)$ tensor multiplet are discussed. Its formulation as an analytic superfield on a suitably defined superspace and its superconformal properties are reviewed. Powers of the field strength superfield define a series of superconformal fields which correspond to the KK multiplets of D=11 supergravity on an $AdS_7\\xz S^4$ background. Correlation functions of these operators are briefly discussed.

  18. Pilots 2.0: DIRAC pilots for all the skies

    E-print Network

    Stagni, F; McNab, A; Luzzi, C

    2015-01-01

    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 s...

  19. The PLATO 2.0 mission. Spanish contribution

    NASA Astrophysics Data System (ADS)

    Mas-Hesse, J. M.; Urqui O'Callaghan, R.; Suárez J. C.; Deeg, H.; Balado, A.

    2015-05-01

    The PLATO 2.0 space mission (PLAnetary Transits and Oscillation of stars) was selected by the ESA Science Programme in February 2014, as the M3 mission to be launched in 2024. PLATO 2.0 will detect terrestrial exoplanets in the habitable zone of bright solar-type stars and characterise their bulk properties. The exoplanets will be detected by the weak eclipses they produce when transiting in front of their parent star, while the long uninterrupted observations will allow also to analyze the oscillations of these stars, yielding their internal structure and evolutionary state. The stellar sample targeted by PLATO is bright enough (V<11.5) to be able to confirm the planets candidates using radial velocity spectroscopy from ground, providing so a complete characterization of the exoplanetary systems. Spain will contribute to the PLATO 2.0 instrument by providing the Focal Plane Assemblies of its 34 telescopes, as well as the Main Electronics Units which will perform onboard and in real time the photometric extraction of the stellar lightcurves.

  20. High-power diode lasers for the 1.9 to 2.2 ?m wavelength range

    NASA Astrophysics Data System (ADS)

    Kelemen, Márc T.; Gilly, Jürgen; Moritz, Rudolf; Rattunde, Marcel; Schmitz, Johannes; Wagner, Joachim

    2008-02-01

    GaSb based diode laser both as single emitters and as arrays, emitting between 1.9 and 2.2 ?m, have a huge potential especially for materials processing, medical applications and as optical pump sources for solid state laser systems emitting in the 2-4 ?m wavelength range. Determined by the absorption characteristics of thermoplastic materials at wavelengths around 2 ?m, the light emitted by the diode laser will be absorbed by the material itself and can thus be used for marking and welding without the addition of e.g. colour pigments. We will present results on different (AlGaIn)(AsSb) quantum-well diode laser single emitters and linear laser arrays, the latter consisting of 20 emitters on a 1 cm long bar, emitting at different wavelengths between 1.9 and 2.2 ?m. To improve on the typically poor fast axis beam divergence of diode lasers emitting at these wavelengths, we abandoned the broadened waveguide concept and changed over to a new waveguide design which features a rather narrow waveguide core. This results in a remarkable reduction in fast axis beam divergence to 43° FWHM for the new waveguide design. Electro-optical and thermal behaviour and the wavelength tunability by current and temperature have been carefully investigated in detail. For single emitters cw output powers of 2 W have been demonstrated. For diode laser arrays mounted on actively cooled heat sinks, more than 20 W in continuous-wave mode have been achieved at a heat sink temperature of 20 °C resulting in wall-plug efficiencies of more than 26%.

  1. Web 2.0 vs. the Semantic Web: A Philosophical Assessment Luciano Floridi1, 2

    E-print Network

    Floridi, Luciano

    Web 2.0 vs. the Semantic Web: A Philosophical Assessment Luciano Floridi1, 2 1 Research Chair at the development of the so-called Semantic Web and Web 2.0 from this perspective and try to forecast their future. Regarding the Semantic Web, I argue that it is a clear and well-defined project, which, despite some

  2. A FORTRAN code for the calculation of sound propagation in a range dependent ocean 2. Range functions and mode coupling

    Microsoft Academic Search

    F. S. Chwieroth

    1978-01-01

    Pierce's adiabatic normal-mode theory of sound propagation in a range dependent ocean duct is extended to the case of sound channels with less than gradual range dependence. A computational method is devised to solve the ensuing coupled range equations by diagonalization. This is applied to a channel with arbitrary (numerically given) range dependence, by dividing it into range segments with

  3. Research, collaboration, and open science using web 2.0.

    PubMed

    Shee, Kevin; Strong, Michael; Guido, Nicholas J; Lue, Robert A; Church, George M; Viel, Alain

    2010-01-01

    There is little doubt that the Internet has transformed the world in which we live. Information that was once archived in bricks and mortar libraries is now only a click away, and people across the globe have become connected in a manner inconceivable only 20 years ago. Although many scientists and educators have embraced the Internet as an invaluable tool for research, education and data sharing, some have been somewhat slower to take full advantage of emerging Web 2.0 technologies. Here we discuss the benefits and challenges of integrating Web 2.0 applications into undergraduate research and education programs, based on our experience utilizing these technologies in a summer undergraduate research program in synthetic biology at Harvard University. We discuss the use of applications including wiki-based documentation, digital brainstorming, and open data sharing via the Web, to facilitate the educational aspects and collaborative progress of undergraduate research projects. We hope to inspire others to integrate these technologies into their own coursework or research projects. PMID:23653712

  4. Emission of secondary ions after grazing impact of keV ions on solid surfaces

    NASA Astrophysics Data System (ADS)

    Nakajima, K.; Lienemann, J.; Eberlein, P.; Kimura, K.; Maass, K.; Winter, H.

    2014-12-01

    We have scattered He+ and Ar+ ions with energies of 10 and 20 keV from solid surfaces and investigated by means of a quadrupole mass spectrometer the emission of secondary ions. Compared to the established method of secondary ion mass spectroscopy (SIMS), the impact of ions proceeds under a grazing angle of incidence of about 2°. In experiments with a Cu(1 0 0) target covered with an ultrathin Fe3O4 film as well as ZnO and ZnMgO surfaces we have explored some basic features of this variant of SIMS concerning the potential application as surface analytical tool.

  5. Long-Range Magnetic Ordering in Pyrochlore Iridate Eu2Ir2O7

    NASA Astrophysics Data System (ADS)

    Zhao, S.; Mackie, J. M.; Maclaughlin, D. E.; Bernal, O. O.; Ohta, Y.; Nakatsuji, S.

    2010-03-01

    In the pyrochlore iridate Eu2Ir2O7 [1,,] Eu^3+ is nonmagnetic (L = S, J = 0) and S(Ir^4+) = 1/2 [1], so that it is a rare example of a frustrated S=1/2 pyrochlore. Spin-glass-like behavior at the metal-insulator transition (MIT) and no magnetic ordering down to 0.3 K have been reported for this compound [2,,]. We discuss ?SR measurements on Eu2Ir2O7 polycrystalline samples that yield strong evidence for long-range magnetic ordering. We observe well-defined muon spin precession frequencies below TM 120 K, consistent with the MIT temperature [2] but indicating long-range ordering instead of a spin-glass like transition. Significant dynamic muon spin relaxation persists to low temperatures, as is often the case in frustrated antiferromagnets. Work supported by NSF (U.S.), Grants 0801407 (UCR) and 0604105 (CSULA), and MEXT (Japan), Grants-in-Aid Nos. 17071003 and 19052003. [1] B. J. Kim et al., Phys. Rev.Lett. 101, 076402 (2008). [2] N. Taira et al., J. Phys.: Condens. Matter 13, 5527 (2001). [3] C. L. Chien and A. W. Sleight, Phys. Rev. B 18, 2031 (1978).

  6. News -Little Geobacter still sparks discoveries after 20 years from the T... file:///C:/Documents%20and%20Settings/pbrown/My%20Documents/re... 1 of 2 6/19/2007 8:33 PM

    E-print Network

    Lovley, Derek

    fuel cells in medical devices implanted in the body, with the microorganisms feeding off blood sugarNews - Little Geobacter still sparks discoveries after 20 years from the T... file:///C:/Documents%20and%20Settings/pbrown/My%20Documents/re... 1 of 2 6/19/2007 8:33 PM Little Geobacter still sparks

  7. 48 CFR 5.404-2 - Announcements of long-range acquisition estimates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Announcements of long-range acquisition estimates. 5.404-2... 5.404-2 Announcements of long-range acquisition estimates. Further publicizing...by announcing through the GPE that long-range acquisition estimates have been...

  8. 48 CFR 5.404-2 - Announcements of long-range acquisition estimates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Announcements of long-range acquisition estimates. 5.404-2... 5.404-2 Announcements of long-range acquisition estimates. Further publicizing...by announcing through the GPE that long-range acquisition estimates have been...

  9. 48 CFR 5.404-2 - Announcements of long-range acquisition estimates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Announcements of long-range acquisition estimates. 5.404-2... 5.404-2 Announcements of long-range acquisition estimates. Further publicizing...by announcing through the GPE that long-range acquisition estimates have been...

  10. 48 CFR 5.404-2 - Announcements of long-range acquisition estimates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Announcements of long-range acquisition estimates. 5.404-2... 5.404-2 Announcements of long-range acquisition estimates. Further publicizing...by announcing through the GPE that long-range acquisition estimates have been...

  11. 48 CFR 5.404-2 - Announcements of long-range acquisition estimates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Announcements of long-range acquisition estimates. 5.404-2... 5.404-2 Announcements of long-range acquisition estimates. Further publicizing...by announcing through the GPE that long-range acquisition estimates have been...

  12. All Solid State Laser System, Continuously Tunable Over 0.2-10 Micron Spectral Range

    E-print Network

    Mirov, Sergey B.

    All Solid State Laser System, Continuously Tunable Over 0.2-10 Micron Spectral Range S.B. Mirov, A continuously tunable in the 0.2-10 .tm spectral range has been developed. It is based on the alexandrite laser range. The main drawbacks and disadvantages of existing solid state lasers include: (1) a limited tuning

  13. Compact, maintainable 80-KeV neutral beam module

    DOEpatents

    Fink, Joel H. (Livermore, CA); Molvik, Arthur W. (Livermore, CA)

    1980-01-01

    A compact, maintainable 80-keV arc chamber, extractor module for a neutral beam system immersed in a vacuum of <10.sup.-2 Torr, incorporating a nested 60-keV gradient shield located midway between the high voltage ion source and surrounding grounded frame. The shield reduces breakdown or arcing path length without increasing the voltage gradient, tends to keep electric fields normal to conducting surfaces rather than skewed and reduces the peak electric field around irregularities on the 80-keV electrodes. The arc chamber or ion source is mounted separately from the extractor or ion accelerator to reduce misalignment of the accelerator and to permit separate maintenance to be performed on these systems. The separate mounting of the ion source provides for maintaining same without removing the ion accelerator.

  14. Non-proportional response between 0.1-100keV energy by means of highly monochromatic synchrotron X-rays

    E-print Network

    Ivan V. Khodyuk; Johan T. M. de Haas; Pieter Dorenbos

    2011-01-24

    Using highly monochromatic X-ray synchrotron irradiation ranging from 9 keV to 100 keV, accurate Lu2SiO5:Ce3+,Ca (LSO), Lu3Al5O12:Pr3+ (LuAG), Lu2Si2O7:Ce3+ (LPS) and Gd2SiO5:Ce3+ (GSO) non-proportional response curves were determined. By utilizing information from escape peaks in pulse height spectra the response curve can be extended down to several keV. A detailed study of the non-proportionality just above the K-edge is presented and from that a method, which we named K-dip spectroscopy, is obtained to reconstruct the electron response curve down to energies as low as 100 eV.

  15. Tracking down the Source Population Responsible for the Unresolved Cosmic 6-8 keV Background

    NASA Astrophysics Data System (ADS)

    Xue, Y. Q.; Wang, S. X.; Brandt, W. N.; Luo, B.; Alexander, D. M.; Bauer, F. E.; Comastri, A.; Fabian, A. C.; Gilli, R.; Lehmer, B. D.; Schneider, D. P.; Vignali, C.; Young, M.

    2012-10-01

    Using the 4 Ms Chandra Deep Field-South (CDF-S) survey, we have identified a sample of 6845 X-ray-undetected galaxies that dominates the unresolved ?20%-25% of the 6-8 keV cosmic X-ray background (XRB). This sample was constructed by applying mass and color cuts to sources from a parent catalog based on GOODS-South Hubble Space Telescope z-band imaging of the central 6'radius area of the 4 Ms CDF-S. The stacked 6-8 keV detection is significant at the 3.9? level, but the stacked emission was not detected in the 4-6 keV band, which indicates the existence of an underlying population of highly obscured active galactic nuclei (AGNs). Further examinations of these 6845 galaxies indicate that the galaxies on the top of the blue cloud and with redshifts of 1 <~ z <~ 3, magnitudes of 25 <~ z 850 <~ 28, and stellar masses of 2 × 108 <~ M sstarf/M ? <~ 2 × 109 make the majority contributions to the unresolved 6-8 keV XRB. Such a population is seemingly surprising given that the majority of the X-ray-detected AGNs reside in massive (gsim 1010 M ?) galaxies. We discuss constraints upon this underlying AGN population, supporting evidence for relatively low mass galaxies hosting highly obscured AGNs, and prospects for further boosting the stacked signal.

  16. Measurement of high-energy (10–60 keV) x-ray spectral line widths with eV accuracy

    SciTech Connect

    Seely, J. F., E-mail: seelyjf@gmail.com; Feldman, U. [Artep Inc., 2922 Excelsior Springs Court, Ellicott City, Maryland 21042 (United States); Glover, J. L.; Hudson, L. T.; Ralchenko, Y.; Henins, Albert [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Pereira, N. [Ecopulse Inc., P. O. Box 528, Springfield, Virginia 22152 (United States); Di Stefano, C. A.; Kuranz, C. C.; Drake, R. P. [University of Michigan, Ann Arbor, Michigan 48109 (United States); Chen, Hui; Williams, G. J.; Park, J. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)

    2014-11-15

    A high resolution crystal spectrometer utilizing a crystal in transmission geometry has been developed and experimentally optimized to measure the widths of emission lines in the 10–60 keV energy range with eV accuracy. The spectrometer achieves high spectral resolution by utilizing crystal planes with small lattice spacings (down to 2d = 0.099 nm), a large crystal bending radius and Rowland circle diameter (965 mm), and an image plate detector with high spatial resolution (60 ?m in the case of the Fuji TR image plate). High resolution W L-shell and K-shell laboratory test spectra in the 10–60 keV range and Ho K-shell spectra near 47 keV recorded at the LLNL Titan laser facility are presented. The Ho K-shell spectra are the highest resolution hard x-ray spectra recorded from a solid target irradiated by a high-intensity laser.

  17. MESURE DU TEMPS DE VIE DU NIVEAU A 2 083 keV DANS LE 140Ce Par M. DORIKENS, J. DEMUYNCK (1), L. DORIKENS-VANPRAET (1)

    E-print Network

    Paris-Sud XI, Université de

    , Belgique. Résumé. 2014 La stabilisation d'un convertisseur temps-amplitude est décrite. Les fluctuations à schéma du convertisseur ( fcg. 1) est analogue à celui publié par R. Ri- chert [1, 2]. La résolution intrinsèque est compa- FIG. 1. - Convertisseur et stabilisation. (1) Chercheurs agréés de l'I. 1. S. N. rable

  18. Specific heat and heat conductivity of BaTiO3 polycrystalline films in the thickness range 20 1100 nm

    Microsoft Academic Search

    B. A. Strukov; S. T. Davitadze; S. N. Kravchun; S. A. Taraskin; M. Goltzman; V. V. Lemanov; S. G. Shulman

    2003-01-01

    Thermal properties - specific heat and heat conductivity coefficient---of polycrystalline BaTiO3 films on massive substrates were studied as a function of the temperature and the film thickness by the ac-hot probe method. The anomalies of specific heat with the film thickness decreasing from 1100 to 20 nm revealed the reduction of Tc and excess entropy of the ferroelectric phase transition

  19. 2.0 Diode Applications 1 of 31 2.1 Introduction

    E-print Network

    Allen, Gale

    2.0 Diode Applications 1 of 31 2.1 Introduction 2.2 Load-Line Analysis #12;2.0 Diode Applications 2 the circuit with the diode on the right. 2) Remove the diode and find a couple of points on the curve of VD vs #12;2.0 Diode Applications 3 of 31 Example 2.1 VD = 0.7 #12;2.0 Diode Applications 4 of 31 2.3 Diode

  20. 59 FR- Drug Export; Antibody to Hepatitis B Surface Antigen HBsAg EIA- 2.0 and HBsAg Confirmatory Assay-2.0

    Federal Register 2010, 2011, 2012, 2013, 2014

    1994-05-02

    ...94N-0151] Drug Export; Antibody to Hepatitis B Surface Antigen HBsAg EIA- 2.0 and...human biological product Antibody to Hepatitis B Surface Antigen HBsAg EIA-2.0 and...human biological product Antibody to Hepatitis B Surface Antigen HBsAg EIA-2.0...

  1. Validation Results for LEWICE 2.0. [Supplement

    NASA Technical Reports Server (NTRS)

    Wright, William B.; Rutkowski, Adam

    1999-01-01

    Two CD-ROMs contain experimental ice shapes and code prediction used for validation of LEWICE 2.0 (see NASA/CR-1999-208690, CASI ID 19990021235). The data include ice shapes for both experiment and for LEWICE, all of the input and output files for the LEWICE cases, JPG files of all plots generated, an electronic copy of the text of the validation report, and a Microsoft Excel(R) spreadsheet containing all of the quantitative measurements taken. The LEWICE source code and executable are not contained on the discs.

  2. IPG Job Manager v2.0 Design Documentation

    NASA Technical Reports Server (NTRS)

    Hu, Chaumin

    2003-01-01

    This viewgraph presentation provides a high-level design of the IPG Job Manager, and satisfies its Master Requirement Specification v2.0 Revision 1.0, 01/29/2003. The presentation includes a Software Architecture/Functional Overview with the following: Job Model; Job Manager Client/Server Architecture; Job Manager Client (Job Manager Client Class Diagram and Job Manager Client Activity Diagram); Job Manager Server (Job Manager Client Class Diagram and Job Manager Client Activity Diagram); Development Environment; Project Plan; Requirement Traceability.

  3. Particle size effect in CaF2:Mn\\/Teflon TLD response at photon energies from 5-1250 keV

    Microsoft Academic Search

    G. A. Carlson; L. Lorence; D. W. Vehar; R. S. Klingler

    1990-01-01

    Thermoluminescent dosimeters (TDLs) fabricated by embedding CaF 2:Mn powder in a Teflon matrix (TTLDs) are sometimes used to monitor dose in silicon-device radiation effects experiments. A potential advantage of TTLDs over other types of TLDs for this application is that their weighted-average mass energy-absorption coefficient is near that of Si. Experimental results are presented which demonstrate that for moderate-energy X-rays,

  4. 0 2 4 6 8 10 12 14 16 18 20 0 5 10 15 20 25 30

    E-print Network

    Wilcock, William

    . The majority of the calls are fin whales, but blue whales were ob- served on at least 9 days (red). In addition 5000 6000 7000 8000 9000 10000 Hour of Day Figure 4. (left) Example of a blue whale vocalization,s Range, km Figure 5. (above) Examples of ray paths between a whale and a seafloor seismometer at 20 km

  5. Web 2.0, Cloud Computing, and Earthquake Forecasting Geoffrey Fox1,2

    E-print Network

    Web 2.0, Cloud Computing, and Earthquake Forecasting Geoffrey Fox1,2 and Marlon Pierce1 1 Community- Science, both in the way data and information (such as earthquake forecasts) are delivered and shared

  6. Virtual Sensors in a Web 2.0 Digital Watershed

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Hill, D. J.; Marini, L.; Kooper, R.; Rodriguez, A.; Myers, J. D.

    2008-12-01

    The lack of rainfall data in many watersheds is one of the major barriers for modeling and studying many environmental and hydrological processes and supporting decision making. There are just not enough rain gages on the ground. To overcome this data scarcity issue, a Web 2.0 digital watershed is developed at NCSA(National Center for Supercomputing Applications), where users can point-and-click on a web-based google map interface and create new precipitation virtual sensors at any location within the same coverage region as a NEXRAD station. A set of scientific workflows are implemented to perform spatial, temporal and thematic transformations to the near-real-time NEXRAD Level II data. Such workflows can be triggered by the users' actions and generate either rainfall rate or rainfall accumulation streaming data at a user-specified time interval. We will discuss some underlying components of this digital watershed, which consists of a semantic content management middleware, a semantically enhanced streaming data toolkit, virtual sensor management functionality, and RESTful (REpresentational State Transfer) web service that can trigger the workflow execution. Such loosely coupled architecture presents a generic framework for constructing a Web 2.0 style digital watershed. An implementation of this architecture at the Upper Illinois Rive Basin will be presented. We will also discuss the implications of the virtual sensor concept for the broad environmental observatory community and how such concept will help us move towards a participatory digital watershed.

  7. Web 2.0 and Marketing Education: Explanations and Experiential Applications

    ERIC Educational Resources Information Center

    Granitz, Neil; Koernig, Stephen K.

    2011-01-01

    Although both experiential learning and Web 2.0 tools focus on creativity, sharing, and collaboration, sparse research has been published integrating a Web 2.0 paradigm with experiential learning in marketing. In this article, Web 2.0 concepts are explained. Web 2.0 is then positioned as a philosophy that can advance experiential learning through…

  8. A search for neutral carbon towards two z = 4.05 submillimetre galaxies, GN20 and GN20.2

    NASA Astrophysics Data System (ADS)

    Casey, C. M.; Chapman, S. C.; Daddi, E.; Dannerbauer, H.; Pope, A.; Scott, D.; Bertoldi, F.; Beswick, R. J.; Blain, A. W.; Cox, P.; Genzel, R.; Greve, T. R.; Ivison, R. J.; Muxlow, T. W. B.; Neri, R.; Omont, A.; Smail, I.; Tacconi, L. J.

    2009-12-01

    Using the IRAM Plateau de Bure Interferometer (PdBI) we have searched for the upper fine structure line of neutral carbon [] and 12CO(J = 7 -> 6) (?rest = 806GHz) towards the submillimetre galaxies (SMGs) GN20 (SMMJ123711.9+622212, z = 4.055) and GN20.2 (SMMJ123708.8+622202, z = 4.051). The far-infrared continuum is detected at 8? significance in GN20, with a flux density of S1.8mm = 1.9 +/- 0.2mJy, while no continuum is detected in GN20.2. Both sources are statistically undetected in both and 12CO(J = 7 -> 6) lines; we derive line luminosity limits for both CI and CO of L' <~ 2 × 1010Kkms-1pc2. Assuming carbon excitation temperatures of Tex = 30K (the galaxies' measured dust temperatures), we infer CI mass limits of MCI < 5.4 × 106Msolar (GN20) and MCI < 6.8 × 106Msolar (GN20.2). The derived CI abundance limits are <1.8 × 10-5 for GN20 and <3.8 × 10-5 for GN20.2, implying that the systems have Milky Way level carbon enrichment (X[CI]/X[H2]) or lower, similar to high-redshift carbon-detected systems (at 5 × 10-5) but about 50 times less than the carbon enrichment of local starburst galaxies. Observations of GN20 and GN20.2 in high-resolution MERLIN+VLA (Multi-Element Radio Linked Interferometer Network+Very Large Array) radio maps of GOODS-N (Great Observatories Origin Deep Survey-North) are used to further constrain the sizes and locations of active regions. We conclude that the physical gas properties of young rapidly evolving systems like GN20 and GN20.2 are likely significantly different than starburst/ULIRG (ultraluminous infrared galaxy) environments in the local Universe yet similar to z ~ 2 SMGs. Unless gravitationally amplified examples can be found, observations of galaxies like GN20 will require the order of magnitude increase in sensitivity of the Atacama Large Millimetre Array (ALMA) to constrain their CI and high-J CO content, despite the fact that they are the brightest systems at z ~ 4.

  9. SUSY and the decay H_2^0-->gg

    E-print Network

    Heinz König

    1996-06-14

    In this talk I present a detailed SUSY QCD calculation of the decay rate of the lightest Higgs boson $H^0_2$\\ into two gluons, where all quarks and scalar quarks are taken within the relevant loop diagrams. I include the mixing of all the three generations of the scalar partners of the left and right handed quarks and show that their contribution is comparable to the quark contribution in the MSSM for small values of the soft SUSY breaking parameter $m_S$. Furthermore in the MSSM the contribution from the bottom quark becomes as large as the top quark contribution for large $\\tan\\beta$\\ and large Higgs masses. As a result, the two gluon decay rate of $H_2^0$\\ is much larger than the two gluon decay rate of an equal mass standard model Higgs boson. I further compare the decay mode of $H^0_2\\rightarrow gg$\\ to the similar decay modes of $H^0_2\\rightarrow c\\overline c$\\ including one loop QCD corrections and show that in some cases $\\Gamma(H^0_2\\rightarrow gg)$\\ is even higher than $\\Gamma(H^0_2\\rightarrow c\\overline c)$.

  10. Interferome v2.0: an updated database of annotated interferon-regulated genes.

    PubMed

    Rusinova, Irina; Forster, Sam; Yu, Simon; Kannan, Anitha; Masse, Marion; Cumming, Helen; Chapman, Ross; Hertzog, Paul J

    2013-01-01

    Interferome v2.0 (http://interferome.its.monash.edu.au/interferome/) is an update of an earlier version of the Interferome DB published in the 2009 NAR database edition. Vastly improved computational infrastructure now enables more complex and faster queries, and supports more data sets from types I, II and III interferon (IFN)-treated cells, mice or humans. Quantitative, MIAME compliant data are collected, subjected to thorough, standardized, quantitative and statistical analyses and then significant changes in gene expression are uploaded. Comprehensive manual collection of metadata in v2.0 allows flexible, detailed search capacity including the parameters: range of -fold change, IFN type, concentration and time, and cell/tissue type. There is no limit to the number of genes that can be used to search the database in a single query. Secondary analysis such as gene ontology, regulatory factors, chromosomal location or tissue expression plots of IFN-regulated genes (IRGs) can be performed in Interferome v2.0, or data can be downloaded in convenient text formats compatible with common secondary analysis programs. Given the importance of IFN to innate immune responses in infectious, inflammatory diseases and cancer, this upgrade of the Interferome to version 2.0 will facilitate the identification of gene signatures of importance in the pathogenesis of these diseases. PMID:23203888

  11. A system for differential neutron scattering experiments in the energy range from 0.5 to 20 MeV

    NASA Astrophysics Data System (ADS)

    Saglime, F. J.; Danon, Y.; Block, R. C.; Rapp, M. J.; Bahran, R. M.; Leinweber, G.; Barry, D. P.; Drindak, N. J.

    2010-08-01

    In order to aid in the improvement of the high energy neutron differential scattering cross-section data, scattering experiments were performed using a collimated source of pulsed neutrons with energies up to 20 MeV from the Rensselaer Polytechnic Institute Linear Accelerator. An array of proton recoil detectors surrounding a sample placed at 30.1 m from the source measures the scattered flux using time-of-flight (TOF) methods. A state of the art digital data acquisition system is used to collect the data from the detector array and stream the digitized data to disk. Software was developed to perform pulse shape analysis, multi-channel analyzer functions, and to generate TOF spectra and angular dependent scattered neutron distributions. Scattering measurements were performed on carbon and molybdenum and compared to the Monte Carlo simulation using various nuclear data libraries.

  12. The Einstein Observatory catalog of IPC x ray sources. Volume 7E: Right ascension range 20h 00m to 23h 59m

    NASA Technical Reports Server (NTRS)

    Harris, D. E.; Forman, W.; Gioia, I. M.; Hale, J. A.; Harnden, F. R., Jr.; Jones, C.; Karakashian, T.; Maccacaro, T.; Mcsweeney, J. D.; Primini, F. A.

    1993-01-01

    The Einstein Observatory (HEAO-2, launched November 13, 1978) achieved radically improved sensitivity over previous x-ray missions through the use of focusing optics which simultaneously afforded greatly reduced background and produced true images. During its 2.5-yr mission, the Einstein X-Ray Telescope was pointed toward some 5,000 celestial targets, most of which were detected, and discovered several thousand additional 'serendipitous' sources in the observed fields. This catalog contains contour diagrams and source data, obtained with the imaging proportional counter in the 0.16 to 3.5 keV energy band, and describes methods for recovering upper limits for any sky position within the observed images. The main catalog consists of six volumes (numbered 2 through 7) of right ascension ordered pages, each containing data for one observation. Along with the primary documentation describing how the catalog was constructed, volume 1 contains a complete source list, results for merged fields, a reference system to published papers, and data useful for calculating upper limits and fluxes.

  13. Sputtering of cryogenic films of hydrogen by keV ions: Thickness dependence and surface morphology

    NASA Astrophysics Data System (ADS)

    Schou, Jørgen; Hilleret, Noel

    2009-08-01

    The sputtering yield induced by keV hydrogen ions measured at CERN and at Risø National Laboratory for solid H 2 and D 2 at temperatures below 4.2 K decreases with increasing film thickness from about 100 × 10 15 molecules/cm 2. For a film thickness comparable to or larger than the ion range the data from Risø show a slight increase, whereas the yield from CERN continues to decrease up to very large film thicknesses, i.e. one order of magnitude larger than the ion range. The different behavior of the yield is discussed in terms of the probable growth modes of the films. The films produced at the Risø setup are quench-condensed films, while those produced at CERN are supposed to grow with large hydrogen aggregates on top of a thin bottom layer.

  14. Depth profile investigation of ?-FeSi2 formed in Si(1 0 0) by high fluence implantation of 50 keV Fe ion and post-thermal vacuum annealing

    NASA Astrophysics Data System (ADS)

    Lakshantha, Wickramaarachchige J.; Kummari, Venkata C.; Reinert, Tilo; McDaniel, Floyd D.; Rout, Bibhudutta

    2014-08-01

    A single phase polycrystalline ?-FeSi2 layer has been synthesized at the near surface region by implantation in Si(1 0 0) of a high fluence (?1017 atoms/cm2) of 50 keV Fe ions and subsequent thermal annealing in vacuum at 800 °C. The depth profile of the implanted Fe atoms in Si(1 0 0) were simulated by the widely used transportation of ions in matter (TRIM) computer code as well as by the dynamic transportation of ions in matter code (T-DYN). The simulated depth profile predictions for this heavy ion implantation process were experimentally verified using Rutherford Backscattering Spectrometry (RBS) and X-ray Photoelectron Spectroscopy (XPS) in combination with Ar-ion etching. The formation of the ?-FeSi2 phase was monitored by X-ray diffraction measurements. The T-DYN simulations show better agreement with the experimental Fe depth profile results than the static TRIM simulations. The experimental and T-DYN simulated results show an asymmetric distribution of Fe concentrated more toward the surface region of the Si substrate.

  15. Malignant catarrhal fever associated with ovine herpesvirus-2 in free-ranging mule deer in Colorado.

    PubMed

    Schultheiss, Patricia C; Van Campen, Hana; Spraker, Terry R; Bishop, Chad; Wolfe, Lisa; Podell, Brendan

    2007-07-01

    Malignant catarrhal fever (MCF) was diagnosed in four free-ranging mule deer (Odocoileus hemionus) in January and February of 2003. Diagnosis was based on typical histologic lesions of lymphocytic vasculitis and PCR identification of ovine herpesvirus-2 (OHV-2) viral genetic sequences in formalin-fixed tissues. The animals were from the Uncompahgre Plateau of southwestern Colorado. Deer from these herds occasionally resided in close proximity to domestic sheep (Ovis aries), the reservoir host of OHV-2, in agricultural valleys adjacent to their winter range. These cases indicate that fatal OHV-2 associated MCF can occur in free-ranging mule deer exposed to domestic sheep that overlap their range. PMID:17699095

  16. Variable pressure-temperature neutron diffraction of wüstite (Fe1-xO): Absence of long-range magnetic order to 20 GPa

    Microsoft Academic Search

    Yang Ding; Jian Xu; Charles T. Prewitt; Russell J. Hemley; Ho-Kwang Mao; John A. Cowan; Jianzhong Zhang; Jiang Qian; Sven C. Vogel; Konstantin Lokshin; Yusheng Zhao

    2005-01-01

    Neutron diffraction measurements have been performed on polycrystalline Fe1-xO (wüstite) up to 20.3 GPa using a large-volume moissanite anvil cell at room temperature to examine the existence of long-range magnetic ordering in the high-pressure rhombohedral phase of the material. This investigation is crucial for understanding the nature of high-pressure phase transitions in Fe1-xO. Low temperature ambient pressure neutron diffraction measurements

  17. Complex permittivity of lanthanum aluminate in the 20 to 300 K temperature range from 26.5 to 40.0 GHz

    Microsoft Academic Search

    F. A. Miranda; W. L. Gordon; K. B. Bhasin; B. T. Ebihara; V. O. Heinen; C. M. Chorey

    1990-01-01

    Dielectric constants of microwave substrates are required in the design of superconducting microwave circuits at various temperatures. In this paper, the results are reported of a study of the complex permittivity of the newly developed lanthanum aluminate (LaAlO3) substrate, in the 20 to 300 K temperature range at frequencies from 26.5 to 40.0 GHz. The value of the complex permittivity

  18. An All-sky Survey for Tens of keV

    NASA Astrophysics Data System (ADS)

    Gruber, D. E.; Matteson, J.; Coburn, W.; Heindl, W.; Pelling, M.; Peterson, L. E.; Rothschild, R. E.; Skelton, T.; Hink, P.

    The HEXIS (High Energy X-Ray Imaging Spectrometer) is a MIDEX-class mission concept to perform a deep survey and continuous monitoring of nearly the entire sky in the 5-200 keV band. It uses arrays of position-sensitive Cadmium-Zinc Telluride (CZT) detectors and coded masks to achieve 26' resolution and a 5 sigma sensitivity (> 20 keV) of 4 milliCrab in one day and 0.2 milliCrab in one year. With these capabilities it is estimated that ~ 5000 sources can be discovered and localized and have their spectra and variability characterized. Hundreds of gamma-ray bursts would be detected each year and localized to < 20'. HEXIS also contains a narrow field, 5(deg) , coded mask imager for detailed studies of selected regions. This has three arc minute resolution and is seven times more sensitive than the all-sky system. The HEXIS detector concept uses crossed strip readout to achieve 0.5 mm resolution pixels for large area arrays, ~ 400 cm(2) . This technique is under development at UCSD and Washington University. Detectors have been studied with tuneable monochromatic x-ray beams and mapped with finely collimated 30 micron beams. These results show that the crossed strip readout has the necessary spatial and spectral characteristics. The HEXIS concept is described and results are presented on the detectors' spatial and spectral properties.

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

    Microsoft Academic Search

    Wang Rong; Feng Zhao; Liu Yunhong; Lu Ming

    2012-01-01

    GaInP\\/GaAs\\/Ge triple-junction solar cells were irradiated with 50 keV and 100 keV protons at fluences of 5 × 1010 cm?2, 1 × 1011 cm?2, 1 × 1012 cm?2, and 1 × 1013 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

  20. WebEQ 2.0 at the Geometry Center

    NSDL National Science Digital Library

    WebEQ 2.0 is a package of Java applets that allow the user to easily incorporate complex mathematical notation into HTML documents. The package supports the WebTeX mark-up language which is similar to LaTeX, but based on MathML, the proposed HTML mathematical mark-up standard. The language is easy-to-learn, especially for those who have had LaTeX experience. The WebEQ engine will be able to process MathML so that documents written using WebEQ should be compatible with this coming standard. There are versions for Unix, Windows 95/NT, and Macintosh, however no special software (beyond a Java capable browser) is necessary to view the math notation. The software is free to students, faculty, and staff of educational institutions for educational uses. It is available for a fee to others.

  1. Do YB2/0 cells produce alien sugars?

    PubMed

    Quagliaroli, D

    2013-12-01

    Olovnikova et al. ("Impact on N-glycosylation profile of monoclonal anti-D antibodies as a way to control their immunoregulatory and cytotoxic properties" (2012) Biochemistry (Moscow), 77, 925-933) mentioned the presence of "alien sugars" on monoclonal antibodies (mAbs) produced by YB2/0 cell line. We summarize in this paper our previous findings on the glycosylation profile of two anti-D mAbs produced in this cell line (LFB-R297 and LFB-R593, so-called Roledumab). Our results show the absence of any immunogenic glycotopes, and furthermore neither immunogenicity nor other serious adverse reactions were observed during clinical trials. PMID:24460972

  2. Coastal Online Analysis and Synthesis Tool 2.0 (COAST)

    NASA Technical Reports Server (NTRS)

    Brown, Richard B.; Navard, Andrew R.; Nguyen, Beth T.

    2009-01-01

    The Coastal Online Assessment and Synthesis Tool (COAST) 3D geobrowser has been developed to integrate disparate coastal datasets from NASA and other sources into a desktop tool that provides new data visualization and analysis capabilities for coastal researchers, managers, and residents. It is built upon the widely used NASA-developed open source World Wind geobrowser from NASA Ames (Patrick Hogan et al.) .Net and C# version is used for development. It is leveraged off of World Wind community shared code samples and COAST 2.0 enhancement direction is based on Coastal science community feedback and needs assessment (GOMA). The main objective is to empower the user to bring more user-meaningful data into multi-layered, multi-temporal spatial context.

  3. Measuring the 511 keV emission in the direction of 1E1740.7-2942 with BATSE

    NASA Technical Reports Server (NTRS)

    Wallyn, P.; Ling, J. C.; Mahoney, W. A.; Wheaton, W. A.; Durouchoux, P.; Corbel, S.; Astier-Perret, L.; Poirot, L.

    1997-01-01

    Observations of the 511 keV emission in the direction of 1E 1740.7-2942 (1E) using the earth burst and transient source experiment (BATSE) onboard the Compton Gamma Ray Observatory (CGRO), are presented. The CGRO phase 1 average spectrum of 1E is calculated using a method which assumes that a given source spectrum is the sum of the flux coming directly from the object and the contribution from the surrounding diffuse emission. The 1E light curve is calculated in the 40 to 150 keV range. It presents a constant flux excess of 70 mCrab in comparison with observations from the SIGMA gamma ray telescope onboard the GRANAT observatory. By removing this contribution, the 1E spectral transition from the low state to the high standard state observed by SIGMA is confirmed, and it is shown that the 511 keV flux is independent of the 1E long term evolution from low state to high standard state. It is concluded that the 511 keV emission of (4.2 +/- 1.3) x 140(exp -4) photons/sq cm s observed in the direction of 1E is mainly diffuse and spatially extended.

  4. Reference guide to WPP version 2.0

    SciTech Connect

    Petersson, A; Sjogreen, B

    2010-01-22

    WPP is a computer program for simulating seismic wave propagation on parallel machines. WPP solves the governing equations in second order formulation using a node-based finite difference approach. The basic numerical method is described in [9]. WPP implements substantial capabilities for 3-D seismic modeling, with a free surface condition on the top boundary, non-reflecting far-field boundary conditions on the other boundaries, point force and point moment tensor source terms with many predefined time dependencies, fully 3-D heterogeneous material model specification, output of synthetic seismograms in the SAC [4] format, output of GMT [11] scripts for laying out simulation information on a map, and output of 2-D slices of (derived quantites of) the solution field as well as the material model. Version 2.0 of WPP allows the free surface boundary condition to be imposed on a curved topography. For this purpose a curvilinear mesh is used near the free surface, extending into the computational domain down to a user specified level. The elastic wave equations and the free surface boundary conditions are discretized on the curvilinear mesh using the energy conserving technique described in [2]. A curvilinear mesh generator is built into WPP and the curvilinear mesh is automatically generated from the topography. Below the curvilinear grid, the elastic wave equation is discretized on Cartesian meshes, which leads to a more computationally efficient algorithm. In version 2.0 of WPP, Cartesian local mesh refinement can be used to make the computational mesh finer near the free surface, where more resolution often is needed to resolve short wave lenghts in the solution, for example in sedimentary basins. The mesh refinement is performed in the vertical direction and each Cartesian grid is constructed from user specified refinement levels. In this approach, the grid size in all three spatial directions is doubled across each mesh refinement interface, leading to substantial savings in memory and computational effort. The energy conserving mesh refinement coupling method described in [10] is used to handle the hanging nodes along the refinement interface. The examples subdirectory of the WPP source distribution contains several examples and validation tests. Many Matlab/octave scripts are provided in the tools directory.

  5. January 20, 2014 draft Biochemistry BIOL 601 schedule -Winter 2014 Version 2.0

    E-print Network

    Habib, Ayman

    Asfandyar Sikandar asfandyar47366075 @gmail.com Ng Suriakarthiga G. March 24, 2014 20 Suriakarthiga Ganesan suriakarthiga@gmail.com Zaremberg Li Wu March 31, 2014 21 Li Wu cosmoflips@gmail.com Zimmerly Trevor Randall April 7, 2014 22 Trevor Randall thesilverdrake@gmail.com Harrison O. Falegan a Each second

  6. Carbonate Stability and Melt Composition in Peridotite-CO2 System to 20 GPa

    NASA Astrophysics Data System (ADS)

    Ghosh, S.; Ohtani, E.; Litasov, K. D.; Suzuki, A.; Terasaki, H.

    2005-12-01

    Carbon dioxide and water are the most important volatile constituents in the Earth and they produce drastic changes in the melting phase relations and partial melt compositions of the mantle peridotite. Study of the peridotite-CO2 system is closely related to petrogenesis of kimberlite and diamond. There are a few high pressure mineral inclusions (i.e. majorite garnet and Ca and Mg perovskite) in diamond which suggest that kimberlites may be originated from the transition zone and lower mantle. The phase relations and melt compositions in the CO2-bearing peridotite at high pressures are poorly constrained, however the kimberlite and basalt-CO2 systems have been studied intensively. Simplified peridotite-CO2 system (like CMS or CMAS) has been studied at pressures up to 12 GPa (Canil and Scarfe, 1990), whereas complex peridotite-CO2 systems have been investigated only at lower pressures (up to 4 GPa, e.g. Wendlandt and Mysen, 1980). In this work we report the preliminary results on the phase relations and melt compositions of a model peridotite-CO2 system determined at 10-20 GPa and temperature range from 1200 to 2100oC. Our results show that solidus of carbonated peridotite is consistent with low-pressure data for CMAS-CO2 system. Liquidus phase at 10-20 GPa is majorite garnet. At 10-15 GPa, crystallization sequence with decreasing temperature is garnet, olivine and clinoenstatite. Magnesite is the most important CO2-rich phase stable in peridotite up to 1600oC at 20 GPa. The partial melt formed by 10-25% melting at 10-20 GPa has high MgO (26-34 wt.%) and FeO (7.0-10.4 wt.%) and low SiO2 (18-36 wt.%) and Al2O3 (0.5-1.3 wt.%) contents. It also contains 6-12 wt.% CaO, 0.6-2.0 wt.% Na2O and 0.1-0.3 wt.% K2O. The CO2 contents in the melts are 14-32 wt.%. The SiO2-poor nature of the partial melts is different from the results for melting of anhydrous or water-bearing peridotite. Partial melting of hydrous peridotite produces the melts enriched in SiO2, which can be related to komatiite magmas. The composition of low degree partial melts (10%) in present experiments is close to magnesiocarbonatites, whereas higher degree melting (20-25%) produce melts, which is close to kimberlite magmas.

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

    NASA Astrophysics Data System (ADS)

    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:2_0.html" xlink:type="simple">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 calculated by Monte Carlo method. Trajectory of each nuclei inside the separator is then calculated by ion optical transfer matrix method. Ratio of the number of trajectories completing their journey up to the detection system to the total number of trajectories is a direct measure of absolute transmission efficiency of the separator. Reasons for new version: The method for calculating mean squared scattering angle (< ? > 2), used earlier [2], was found to be inadequate particularly for low energy heavy residues. Energy loss of beam in the target-backing foil and energy loss of residues in the charge-reset foil (wherever used) needed to be taken into account for better matching of simulated residue parameters with measurements. Summary of revisions: A new method [3] for calculating multiple small angle Coulomb scattering of residues in the target has been adopted. The change is incorporated in function Weibull() in the program ters_pti2.c. Isotopically enriched targets are made on a thin backing foil (usually made of carbon) quite often. Energy loss of beam in the backing foil (assuming beam is made to pass through the backing foil first, which is the usual practice) need to be taken into account. This calls for minor changes in the input file ters_pti2.inp. Following is the modified list of input parameters in this file with explanation. Atomic no. and mass no. of projectile and target. Projectile energy [MeV] in laboratory. Dia. [mm] of (circular) beam spot and target thickness [mg/cm2]. Atomic no. and mass no. of the backing material and thickness [mg/cm2] of the backing foil.

  8. A 20-Gb/s 1: 2 demultiplexer in 0.18-?m CMOS

    NASA Astrophysics Data System (ADS)

    Changchun, Zhang; Zhigong, Wang; Si, Shi; Wei, Li

    2009-05-01

    A 1: 2 demultiplexer (DEMUX) has been designed and fabricated in SMIC's standard 0.18-?m CMOS technology, based on standard CML logic and current-density-centric design philosophy. For the integrity of the DEMUX and the reliability of the internal operations, a data input buffer and a static latch were adopted. At the same time, the static latch enables the IC to work in a broader data rate range than the dynamic latch. Measurement results show that under a 1.8-V supply voltage, the DEMUX can operate reliably at any data rate in the range of 5--20 Gb/s. The chip size is 875 × 640 ?m2 and the power consumption is 144 mW, in which the core circuit has a share of less than 28%.

  9. Hyperscaling violation in the 2D 8-state Potts model with long-range correlated disorder

    E-print Network

    Boyer, Edmond

    epl draft Hyperscaling violation in the 2D 8-state Potts model with long- range correlated disorder C. Chatelain1,2 1 School of Physics, Indian Institute of Science Education and Research (IISER long-range correlated disorder is coupled to energy density. Critical exponents are estimated by means

  10. The wild type bacterial Co(2+)/Co(2+)-phosphotriesterase shows a middle-range thermostability.

    PubMed

    Rochu, Daniel; Beaufet, Nadège; Renault, Frédérique; Viguié, Nathalie; Masson, Patrick

    2002-02-11

    The phosphotriesterase (PTE) from Pseudomonas diminuta, a metalloenzyme that catalyses the hydrolysis of organophosphorus pesticides and nerve agents, has been described as a remarkably heat-stable protein [Grimsley et al., Biochemistry 36 (1997), 14366-14374]. Because substitution of the naturally occurring zinc ions by cobalt ions was found to enhance the enzyme catalytic activity, we investigated the thermal stability of the Co(2+)/Co(2+)-PTE. This study, carried out using capillary electrophoresis under optimised conditions in the pH range 9-10 compatible with optimal enzyme activity, provided evidence for irreversible denaturation according to the Lumry-Eyring model. A temperature-induced conformational transition (T(m) approximately equal to 58 degrees C) and an early growing of aggregates were observed. Comparison of UV spectra with heat-induced inactivation data clearly demonstrated that the PTE state populated above T(m) was neither native nor active. Differential scanning calorimetry showed only an exothermic trace due to aggregation of the denatured protein at T=76 degrees C. Accordingly, the temperature-induced denaturation process of the PTE could be described by a consecutive reaction model, including formation of an intermediate with enhanced activity at T approximately equal to 45 degrees C and an inactive unfolded state populated at T approximately equal to 58 degrees C, which leads to denatured aggregates. Thus, the wild type Co(2+)/Co(2+)-PTE displays a middle-range thermostability. Hence, for decontamination purposes under extreme Earth temperatures, wild type and engineered mutants of PTE substituted with other metal cations should be evaluated. PMID:11904217

  11. NQS - NETWORK QUEUING SYSTEM, VERSION 2.0 (UNIX VERSION)

    NASA Technical Reports Server (NTRS)

    Walter, H.

    1994-01-01

    The Network Queuing System, NQS, is a versatile batch and device queuing facility for a single Unix computer or a group of networked computers. With the Unix operating system as a common interface, the user can invoke the NQS collection of user-space programs to move batch and device jobs freely around the different computer hardware tied into the network. NQS provides facilities for remote queuing, request routing, remote status, queue status controls, batch request resource quota limits, and remote output return. This program was developed as part of an effort aimed at tying together diverse UNIX based machines into NASA's Numerical Aerodynamic Simulator Processing System Network. This revision of NQS allows for creating, deleting, adding and setting of complexes that aid in limiting the number of requests to be handled at one time. It also has improved device-oriented queues along with some revision of the displays. NQS was designed to meet the following goals: 1) Provide for the full support of both batch and device requests. 2) Support all of the resource quotas enforceable by the underlying UNIX kernel implementation that are relevant to any particular batch request and its corresponding batch queue. 3) Support remote queuing and routing of batch and device requests throughout the NQS network. 4) Support queue access restrictions through user and group access lists for all queues. 5) Enable networked output return of both output and error files to possibly remote machines. 6) Allow mapping of accounts across machine boundaries. 7) Provide friendly configuration and modification mechanisms for each installation. 8) Support status operations across the network, without requiring a user to log in on remote target machines. 9) Provide for file staging or copying of files for movement to the actual execution machine. To support batch and device requests, NQS v.2 implements three queue types--batch, device and pipe. Batch queues hold and prioritize batch requests; device queues hold and prioritize device requests; pipe queues transport both batch and device requests to other batch, device, or pipe queues at local or remote machines. Unique to batch queues are resource quota limits that restrict the amounts of different resources that a batch request can consume during execution. Unique to each device queue is a set of one or more devices, such as a line printer, to which requests can be sent for execution. Pipe queues have associated destinations to which they route and deliver requests. If the proper destination machine is down or unreachable, pipe queues are able to requeue the request and deliver it later when the destination is available. All NQS network conversations are performed using the Berkeley socket mechanism as ported into the respective vendor kernels. NQS is written in C language. The generic UNIX version (ARC-13179) has been successfully implemented on a variety of UNIX platforms, including Sun3 and Sun4 series computers, SGI IRIS computers running IRIX 3.3, DEC computers running ULTRIX 4.1, AMDAHL computers running UTS 1.3 and 2.1, platforms running BSD 4.3 UNIX. The IBM RS/6000 AIX version (COS-10042) is a vendor port. NQS 2.0 will also communicate with the Cray Research, Inc. and Convex, Inc. versions of NQS. The standard distribution medium for either machine version of NQS 2.0 is a 60Mb, QIC-24, .25 inch streaming magnetic tape cartridge in UNIX tar format. Upon request the generic UNIX version (ARC-13179) can be provided in UNIX tar format on alternate media. Please contact COSMIC to discuss the availability and cost of media to meet your specific needs. An electronic copy of the NQS 2.0 documentation is included on the program media. NQS 2.0 was released in 1991. The IBM RS/6000 port of NQS was developed in 1992. IRIX is a trademark of Silicon Graphics Inc. IRIS is a registered trademark of Silicon Graphics Inc. UNIX is a registered trademark of UNIX System Laboratories Inc. Sun3 and Sun4 are trademarks of Sun Microsystems Inc. DEC and ULTRIX are trademarks of Digital Equipment Corporation.

  12. A GHz range electromagnetic wave absorber with wide bandwidth made of FeCo\\/Y 2O 3 nanocomposites

    Microsoft Academic Search

    Jiu Rong Liu; Masahiro Itoh; Jianzhuang Jiang; Ken-ichi Machida

    2004-01-01

    Nanocomposites consisting of fine particles of FeCo (?30nm) and Y2O3 (?15nm) have been prepared from an intermetallic compound Y2(Fe0.5Co0.5)17 by melt-spinning techniques and subsequent hydrogenation-disproportionation and oxidation treatments. The electromagnetic (EM) wave absorption properties were characterized in a frequency range of 0.05–20.05GHz. The measured real part (?r?) and imaginary part (?r?) of the relative permittivity were small and approximately constant

  13. 2 in 20 Community Contract The 2 in 20 Community was created in 1992 to provide a supportive environment for lesbian,

    E-print Network

    Massachusetts at Amherst, University of

    2 in 20 Community Contract The 2 in 20 Community was created in 1992 to provide a supportive and other initiatives to build community, residents are encouraged to learn about and actively seek ways to the community include, but are not limited to, The Stonewall Center and Pride Alliance. As a member of the 2

  14. 2.20 Properties of Rocks and Minerals -Magnetic Properties of Rocks and Minerals

    E-print Network

    Dunin-Borkowski, Rafal E.

    2.20 Properties of Rocks and Minerals - Magnetic Properties of Rocks and Minerals R. J. Harrison, R 621 622 623 623 579 #12;580 Magnetic Properties of Rocks and Minerals 2.20.5.3 2.20.5.4 2, and are present in all types of rocks, sediments, and soils. These minerals retain a memory of the geomagnetic

  15. Measurements of the neutron-proton and neutron-carbon total cross section from 150 to 800 keV

    E-print Network

    Daub, B. H.

    There have been very few measurements of the total cross section for np scattering below 500 keV. To differentiate among NN potential models, improved cross section data between 20 and 600 keV are required. We measured the ...

  16. On the Reversible Conjugation of [17-D 2 ]GA 20 in Seedlings of Phaseolus coccineus L

    Microsoft Academic Search

    G. Schneider; M. Koch; P. Fuchs

    1999-01-01

    .   After administering [17-D2]GA20 to Phaseolus coccineus L. cv. Preisgewinner seedlings, [17-D2]GA20-O-glucoside was identified by liquid chromatography (LC)\\/ESI-tandem mass spectrometry (MS). Likewise, by LC\\/ESI-tandem MS\\u000a the metabolic formation of [17-D2]GA20 glucosyl ester was established. The application of both [17-D2]-labeled GA20 13-O-glucoside and GA20 glucosyl ester to Phaseolus coccineus L. seedlings resulted in free [17-D2]GA20 by gas chromatography\\/MS. The results demonstrate

  17. "Old Wine in Even Newer Bottles": The Uneasy Relationship between Web 2.0 Technologies and European School Collaboration

    ERIC Educational Resources Information Center

    Gouseti, Anastasia

    2013-01-01

    The idea of using digital technologies and in particular web 2.0 tools to enhance school collaboration has recently been received with great enthusiasm and a range of new collaborative initiatives has emerged. Through a comparative qualitative case study of four schools in the UK and Greece, this article analyses how online tools are supporting…

  18. Characterization of Infrared Range-Finder PBS03JN for 2-D Mapping

    Microsoft Academic Search

    Majd Alwan; Matthew Wagner; Glenn S. Wasson; Pradip Sheth

    2005-01-01

    This paper presents a characterization study of the HOKUYO PBS-03JN Infrared range-finder and compares it to the characterization of the SICK LMS-200 laser range- finder for use in indoor 2-D mapping. Many parameters that could affect the performance of the sensor including warm-up time, divergence of the detection beam, usable detection range in the azimuth, target surface, color, and size

  19. Short and Long Range Magnetic Ordering in beta-MnO2 ---A Temperature Study

    Microsoft Academic Search

    Marcin Regulski; Radoslaw Przenioslo; Izabela Sosnowska; Jens-Uwe Hoffmann

    2004-01-01

    The magnetic long range ordering (LRO) and short range ordering (SRO) in beta-MnO2 has been studied by neutron powder diffraction. Below TN=92.5(1) K beta-MnO2 has an incommensurate modulated magnetic LRO with temperature dependent propagation vector length kz. The values of kz show a maximum, corresponding to kz = (2\\/7) + 0.0120(1), near 90 K. The c lattice constant has a

  20. Preparation of aqueous colloidal mesostructured and mesoporous silica nanoparticles with controlled particle size in a very wide range from 20 nm to 700 nm

    NASA Astrophysics Data System (ADS)

    Yamada, Hironori; Urata, Chihiro; Ujiie, Hiroto; Yamauchi, Yusuke; Kuroda, Kazuyuki

    2013-06-01

    Particle size control of colloidal mesoporous silica nanoparticles (CMPS) in a very wide range is quite significant for the design of CMPS toward various applications, such as catalysis and drug delivery. Various types of CMPS and their precursors (colloidal mesostructured silica nanoparticles (CMSS)) with different particle sizes (ca. 20-700 nm) were newly prepared from tetraalkoxysilanes with different alkoxy groups (Si(OR)4, R = Me, Et, Pr, and Bu) in the presence of alcohols (R'OH, R' = Me, Et, Pr, and Bu) as additives. CMSS with larger particle size were obtained by using tetrabutoxysilane (TBOS) and by increasing the amount of BuOH, which is explained by both the difference in the hydrolysis rates of tetraalkoxysilanes themselves and the effect of added alcohols on the hydrolysis rates of tetraalkoxysilanes. Larger amounts of alcohols with longer alkyl chains decrease the hydrolysis rates of tetraalkoxysilanes and the subsequent formation rates of silica species. Thus, the preferential particle growth of CMSS to nucleation occurs, and larger CMSS are formed. Highly dispersed CMPS were prepared by the removal of surfactants of CMSS by dialysis which can lead to the preparation of CMPS without aggregation. Therefore, the particle size control through the tuning of the hydrolysis rate of tetraalkoxysilanes can be conducted by a one-pot and easy approach. Even larger CMPS (ca. 700 nm in size) show relatively high dispersibility. This dispersibility will surely contribute to the design of materials both retaining nanoscale characteristics and avoiding various nanorisks.Particle size control of colloidal mesoporous silica nanoparticles (CMPS) in a very wide range is quite significant for the design of CMPS toward various applications, such as catalysis and drug delivery. Various types of CMPS and their precursors (colloidal mesostructured silica nanoparticles (CMSS)) with different particle sizes (ca. 20-700 nm) were newly prepared from tetraalkoxysilanes with different alkoxy groups (Si(OR)4, R = Me, Et, Pr, and Bu) in the presence of alcohols (R'OH, R' = Me, Et, Pr, and Bu) as additives. CMSS with larger particle size were obtained by using tetrabutoxysilane (TBOS) and by increasing the amount of BuOH, which is explained by both the difference in the hydrolysis rates of tetraalkoxysilanes themselves and the effect of added alcohols on the hydrolysis rates of tetraalkoxysilanes. Larger amounts of alcohols with longer alkyl chains decrease the hydrolysis rates of tetraalkoxysilanes and the subsequent formation rates of silica species. Thus, the preferential particle growth of CMSS to nucleation occurs, and larger CMSS are formed. Highly dispersed CMPS were prepared by the removal of surfactants of CMSS by dialysis which can lead to the preparation of CMPS without aggregation. Therefore, the particle size control through the tuning of the hydrolysis rate of tetraalkoxysilanes can be conducted by a one-pot and easy approach. Even larger CMPS (ca. 700 nm in size) show relatively high dispersibility. This dispersibility will surely contribute to the design of materials both retaining nanoscale characteristics and avoiding various nanorisks. Electronic supplementary information (ESI) available: Additional data on ?-potential, hydrodynamic diameter, physicochemical properties, particle size distributions, appearance, UV-vis transmittance spectra, TEM images, TG curves, XRD patterns, N2 adsorption-desorption isotherms of CMSS and CMPS. See DOI: 10.1039/c3nr00334e